/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp

Bug Summary

File:	llvm/lib/Transforms/Utils/SimplifyCFG.cpp
Warning:	line 3106, column 11 3rd function call argument is an uninitialized value

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SimplifyCFG.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/build-llvm/lib/Transforms/Utils -I /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils -I /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/build-llvm/include -I /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/build-llvm/lib/Transforms/Utils -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2021-01-22-054259-40355-1 -x c++ /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp

/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp

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1//===- SimplifyCFG.cpp - Code to perform CFG simplification ---------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Peephole optimize the CFG.
10//
11//===----------------------------------------------------------------------===//

13#include "llvm/ADT/APInt.h"
14#include "llvm/ADT/ArrayRef.h"
15#include "llvm/ADT/DenseMap.h"
16#include "llvm/ADT/MapVector.h"
17#include "llvm/ADT/Optional.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/ScopeExit.h"
20#include "llvm/ADT/Sequence.h"
21#include "llvm/ADT/SetOperations.h"
22#include "llvm/ADT/SetVector.h"
23#include "llvm/ADT/SmallPtrSet.h"
24#include "llvm/ADT/SmallVector.h"
25#include "llvm/ADT/Statistic.h"
26#include "llvm/ADT/StringRef.h"
27#include "llvm/Analysis/AssumptionCache.h"
28#include "llvm/Analysis/ConstantFolding.h"
29#include "llvm/Analysis/EHPersonalities.h"
30#include "llvm/Analysis/GuardUtils.h"
31#include "llvm/Analysis/InstructionSimplify.h"
32#include "llvm/Analysis/MemorySSA.h"
33#include "llvm/Analysis/MemorySSAUpdater.h"
34#include "llvm/Analysis/TargetTransformInfo.h"
35#include "llvm/Analysis/ValueTracking.h"
36#include "llvm/IR/Attributes.h"
37#include "llvm/IR/BasicBlock.h"
38#include "llvm/IR/CFG.h"
39#include "llvm/IR/Constant.h"
40#include "llvm/IR/ConstantRange.h"
41#include "llvm/IR/Constants.h"
42#include "llvm/IR/DataLayout.h"
43#include "llvm/IR/DerivedTypes.h"
44#include "llvm/IR/Function.h"
45#include "llvm/IR/GlobalValue.h"
46#include "llvm/IR/GlobalVariable.h"
47#include "llvm/IR/IRBuilder.h"
48#include "llvm/IR/InstrTypes.h"
49#include "llvm/IR/Instruction.h"
50#include "llvm/IR/Instructions.h"
51#include "llvm/IR/IntrinsicInst.h"
52#include "llvm/IR/Intrinsics.h"
53#include "llvm/IR/LLVMContext.h"
54#include "llvm/IR/MDBuilder.h"
55#include "llvm/IR/Metadata.h"
56#include "llvm/IR/Module.h"
57#include "llvm/IR/NoFolder.h"
58#include "llvm/IR/Operator.h"
59#include "llvm/IR/PatternMatch.h"
60#include "llvm/IR/Type.h"
61#include "llvm/IR/Use.h"
62#include "llvm/IR/User.h"
63#include "llvm/IR/Value.h"
64#include "llvm/Support/Casting.h"
65#include "llvm/Support/CommandLine.h"
66#include "llvm/Support/Debug.h"
67#include "llvm/Support/ErrorHandling.h"
68#include "llvm/Support/KnownBits.h"
69#include "llvm/Support/MathExtras.h"
70#include "llvm/Support/raw_ostream.h"
71#include "llvm/Transforms/Utils/BasicBlockUtils.h"
72#include "llvm/Transforms/Utils/Local.h"
73#include "llvm/Transforms/Utils/SSAUpdater.h"
74#include "llvm/Transforms/Utils/ValueMapper.h"
75#include <algorithm>
76#include <cassert>
77#include <climits>
78#include <cstddef>
79#include <cstdint>
80#include <iterator>
81#include <map>
82#include <set>
83#include <tuple>
84#include <utility>
85#include <vector>

87using namespace llvm;
88using namespace PatternMatch;

90#define DEBUG_TYPE"simplifycfg" "simplifycfg"

92cl::opt<bool> llvm::RequireAndPreserveDomTree(
  "simplifycfg-require-and-preserve-domtree", cl::Hidden, cl::ZeroOrMore,
  cl::init(false),
  cl::desc("Temorary development switch used to gradually uplift SimplifyCFG "
           "into preserving DomTree,"));

98// Chosen as 2 so as to be cheap, but still to have enough power to fold
99// a select, so the "clamp" idiom (of a min followed by a max) will be caught.
100// To catch this, we need to fold a compare and a select, hence '2' being the
101// minimum reasonable default.
102static cl::opt<unsigned> PHINodeFoldingThreshold(
  "phi-node-folding-threshold", cl::Hidden, cl::init(2),
  cl::desc(
      "Control the amount of phi node folding to perform (default = 2)"));

107static cl::opt<unsigned> TwoEntryPHINodeFoldingThreshold(
  "two-entry-phi-node-folding-threshold", cl::Hidden, cl::init(4),
  cl::desc("Control the maximal total instruction cost that we are willing "
           "to speculatively execute to fold a 2-entry PHI node into a "
           "select (default = 4)"));

113static cl::opt<bool> DupRet(
  "simplifycfg-dup-ret", cl::Hidden, cl::init(false),
  cl::desc("Duplicate return instructions into unconditional branches"));

117static cl::opt<bool>
  HoistCommon("simplifycfg-hoist-common", cl::Hidden, cl::init(true),
              cl::desc("Hoist common instructions up to the parent block"));

121static cl::opt<bool>
  SinkCommon("simplifycfg-sink-common", cl::Hidden, cl::init(true),
             cl::desc("Sink common instructions down to the end block"));

125static cl::opt<bool> HoistCondStores(
  "simplifycfg-hoist-cond-stores", cl::Hidden, cl::init(true),
  cl::desc("Hoist conditional stores if an unconditional store precedes"));

129static cl::opt<bool> MergeCondStores(
  "simplifycfg-merge-cond-stores", cl::Hidden, cl::init(true),
  cl::desc("Hoist conditional stores even if an unconditional store does not "
           "precede - hoist multiple conditional stores into a single "
           "predicated store"));

135static cl::opt<bool> MergeCondStoresAggressively(
  "simplifycfg-merge-cond-stores-aggressively", cl::Hidden, cl::init(false),
  cl::desc("When merging conditional stores, do so even if the resultant "
           "basic blocks are unlikely to be if-converted as a result"));

140static cl::opt<bool> SpeculateOneExpensiveInst(
  "speculate-one-expensive-inst", cl::Hidden, cl::init(true),
  cl::desc("Allow exactly one expensive instruction to be speculatively "
           "executed"));

145static cl::opt<unsigned> MaxSpeculationDepth(
  "max-speculation-depth", cl::Hidden, cl::init(10),
  cl::desc("Limit maximum recursion depth when calculating costs of "
           "speculatively executed instructions"));

150static cl::opt<int>
151MaxSmallBlockSize("simplifycfg-max-small-block-size", cl::Hidden, cl::init(10),
                cl::desc("Max size of a block which is still considered "
                         "small enough to thread through"));

155// Two is chosen to allow one negation and a logical combine.
156static cl::opt<unsigned>
  BranchFoldThreshold("simplifycfg-branch-fold-threshold", cl::Hidden,
                      cl::init(2),
                      cl::desc("Maximum cost of combining conditions when "
                               "folding branches"));

162STATISTIC(NumBitMaps, "Number of switch instructions turned into bitmaps")static llvm::Statistic NumBitMaps = {"simplifycfg", "NumBitMaps"
, "Number of switch instructions turned into bitmaps"};
163STATISTIC(NumLinearMaps,static llvm::Statistic NumLinearMaps = {"simplifycfg", "NumLinearMaps"
, "Number of switch instructions turned into linear mapping"}
        "Number of switch instructions turned into linear mapping")static llvm::Statistic NumLinearMaps = {"simplifycfg", "NumLinearMaps"
, "Number of switch instructions turned into linear mapping"};
165STATISTIC(NumLookupTables,static llvm::Statistic NumLookupTables = {"simplifycfg", "NumLookupTables"
, "Number of switch instructions turned into lookup tables"}
        "Number of switch instructions turned into lookup tables")static llvm::Statistic NumLookupTables = {"simplifycfg", "NumLookupTables"
, "Number of switch instructions turned into lookup tables"};
167STATISTIC(static llvm::Statistic NumLookupTablesHoles = {"simplifycfg",
 "NumLookupTablesHoles", "Number of switch instructions turned into lookup tables (holes checked)"
}
  NumLookupTablesHoles,static llvm::Statistic NumLookupTablesHoles = {"simplifycfg",
 "NumLookupTablesHoles", "Number of switch instructions turned into lookup tables (holes checked)"
}
  "Number of switch instructions turned into lookup tables (holes checked)")static llvm::Statistic NumLookupTablesHoles = {"simplifycfg",
 "NumLookupTablesHoles", "Number of switch instructions turned into lookup tables (holes checked)"
};
170STATISTIC(NumTableCmpReuses, "Number of reused switch table lookup compares")static llvm::Statistic NumTableCmpReuses = {"simplifycfg", "NumTableCmpReuses"
, "Number of reused switch table lookup compares"};
171STATISTIC(NumFoldValueComparisonIntoPredecessors,static llvm::Statistic NumFoldValueComparisonIntoPredecessors
 = {"simplifycfg", "NumFoldValueComparisonIntoPredecessors", "Number of value comparisons folded into predecessor basic blocks"
}
        "Number of value comparisons folded into predecessor basic blocks")static llvm::Statistic NumFoldValueComparisonIntoPredecessors
 = {"simplifycfg", "NumFoldValueComparisonIntoPredecessors", "Number of value comparisons folded into predecessor basic blocks"
};
173STATISTIC(NumFoldBranchToCommonDest,static llvm::Statistic NumFoldBranchToCommonDest = {"simplifycfg"
, "NumFoldBranchToCommonDest", "Number of branches folded into predecessor basic block"
}
        "Number of branches folded into predecessor basic block")static llvm::Statistic NumFoldBranchToCommonDest = {"simplifycfg"
, "NumFoldBranchToCommonDest", "Number of branches folded into predecessor basic block"
};
175STATISTIC(static llvm::Statistic NumHoistCommonCode = {"simplifycfg", "NumHoistCommonCode"
, "Number of common instruction 'blocks' hoisted up to the begin block"
}
  NumHoistCommonCode,static llvm::Statistic NumHoistCommonCode = {"simplifycfg", "NumHoistCommonCode"
, "Number of common instruction 'blocks' hoisted up to the begin block"
}
  "Number of common instruction 'blocks' hoisted up to the begin block")static llvm::Statistic NumHoistCommonCode = {"simplifycfg", "NumHoistCommonCode"
, "Number of common instruction 'blocks' hoisted up to the begin block"
};
178STATISTIC(NumHoistCommonInstrs,static llvm::Statistic NumHoistCommonInstrs = {"simplifycfg",
 "NumHoistCommonInstrs", "Number of common instructions hoisted up to the begin block"
}
        "Number of common instructions hoisted up to the begin block")static llvm::Statistic NumHoistCommonInstrs = {"simplifycfg",
 "NumHoistCommonInstrs", "Number of common instructions hoisted up to the begin block"
};
180STATISTIC(NumSinkCommonCode,static llvm::Statistic NumSinkCommonCode = {"simplifycfg", "NumSinkCommonCode"
, "Number of common instruction 'blocks' sunk down to the end block"
}
        "Number of common instruction 'blocks' sunk down to the end block")static llvm::Statistic NumSinkCommonCode = {"simplifycfg", "NumSinkCommonCode"
, "Number of common instruction 'blocks' sunk down to the end block"
};
182STATISTIC(NumSinkCommonInstrs,static llvm::Statistic NumSinkCommonInstrs = {"simplifycfg", "NumSinkCommonInstrs"
, "Number of common instructions sunk down to the end block"}
        "Number of common instructions sunk down to the end block")static llvm::Statistic NumSinkCommonInstrs = {"simplifycfg", "NumSinkCommonInstrs"
, "Number of common instructions sunk down to the end block"};
184STATISTIC(NumSpeculations, "Number of speculative executed instructions")static llvm::Statistic NumSpeculations = {"simplifycfg", "NumSpeculations"
, "Number of speculative executed instructions"};
185STATISTIC(NumInvokes,static llvm::Statistic NumInvokes = {"simplifycfg", "NumInvokes"
, "Number of invokes with empty resume blocks simplified into calls"
}
        "Number of invokes with empty resume blocks simplified into calls")static llvm::Statistic NumInvokes = {"simplifycfg", "NumInvokes"
, "Number of invokes with empty resume blocks simplified into calls"
};

188namespace {

190// The first field contains the value that the switch produces when a certain
191// case group is selected, and the second field is a vector containing the
192// cases composing the case group.
193using SwitchCaseResultVectorTy =
  SmallVector<std::pair<Constant *, SmallVector<ConstantInt *, 4>>, 2>;

196// The first field contains the phi node that generates a result of the switch
197// and the second field contains the value generated for a certain case in the
198// switch for that PHI.
199using SwitchCaseResultsTy = SmallVector<std::pair<PHINode *, Constant *>, 4>;

201/// ValueEqualityComparisonCase - Represents a case of a switch.
202struct ValueEqualityComparisonCase {
ConstantInt *Value;
BasicBlock *Dest;

ValueEqualityComparisonCase(ConstantInt *Value, BasicBlock *Dest)
    : Value(Value), Dest(Dest) {}

bool operator<(ValueEqualityComparisonCase RHS) const {
  // Comparing pointers is ok as we only rely on the order for uniquing.
  return Value < RHS.Value;
}

bool operator==(BasicBlock *RHSDest) const { return Dest == RHSDest; }
215};

217class SimplifyCFGOpt {
const TargetTransformInfo &TTI;
DomTreeUpdater *DTU;
const DataLayout &DL;
SmallPtrSetImpl<BasicBlock *> *LoopHeaders;
const SimplifyCFGOptions &Options;
bool Resimplify;

Value *isValueEqualityComparison(Instruction *TI);
BasicBlock *GetValueEqualityComparisonCases(
    Instruction *TI, std::vector<ValueEqualityComparisonCase> &Cases);
bool SimplifyEqualityComparisonWithOnlyPredecessor(Instruction *TI,
                                                   BasicBlock *Pred,
                                                   IRBuilder<> &Builder);
bool FoldValueComparisonIntoPredecessors(Instruction *TI,
                                         IRBuilder<> &Builder);

bool simplifyReturn(ReturnInst *RI, IRBuilder<> &Builder);
bool simplifyResume(ResumeInst *RI, IRBuilder<> &Builder);
bool simplifySingleResume(ResumeInst *RI);
bool simplifyCommonResume(ResumeInst *RI);
bool simplifyCleanupReturn(CleanupReturnInst *RI);
bool simplifyUnreachable(UnreachableInst *UI);
bool simplifySwitch(SwitchInst *SI, IRBuilder<> &Builder);
bool simplifyIndirectBr(IndirectBrInst *IBI);
bool simplifyBranch(BranchInst *Branch, IRBuilder<> &Builder);
bool simplifyUncondBranch(BranchInst *BI, IRBuilder<> &Builder);
bool simplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder);
bool SimplifyCondBranchToTwoReturns(BranchInst *BI, IRBuilder<> &Builder);

bool tryToSimplifyUncondBranchWithICmpInIt(ICmpInst *ICI,
                                           IRBuilder<> &Builder);

bool HoistThenElseCodeToIf(BranchInst *BI, const TargetTransformInfo &TTI);
bool SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *ThenBB,
                            const TargetTransformInfo &TTI);
bool SimplifyTerminatorOnSelect(Instruction *OldTerm, Value *Cond,
                                BasicBlock *TrueBB, BasicBlock *FalseBB,
                                uint32_t TrueWeight, uint32_t FalseWeight);
bool SimplifyBranchOnICmpChain(BranchInst *BI, IRBuilder<> &Builder,
                               const DataLayout &DL);
bool SimplifySwitchOnSelect(SwitchInst *SI, SelectInst *Select);
bool SimplifyIndirectBrOnSelect(IndirectBrInst *IBI, SelectInst *SI);
bool TurnSwitchRangeIntoICmp(SwitchInst *SI, IRBuilder<> &Builder);

262public:
SimplifyCFGOpt(const TargetTransformInfo &TTI, DomTreeUpdater *DTU,
               const DataLayout &DL,
               SmallPtrSetImpl<BasicBlock *> *LoopHeaders,
               const SimplifyCFGOptions &Opts)
    : TTI(TTI), DTU(DTU), DL(DL), LoopHeaders(LoopHeaders), Options(Opts) {
  assert((!DTU || !DTU->hasPostDomTree()) &&(((!DTU || !DTU->hasPostDomTree()) && "SimplifyCFG is not yet capable of maintaining validity of a "
 "PostDomTree, so don't ask for it.") ? static_cast<void>
 (0) : __assert_fail ("(!DTU || !DTU->hasPostDomTree()) && \"SimplifyCFG is not yet capable of maintaining validity of a \" \"PostDomTree, so don't ask for it.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 270, __PRETTY_FUNCTION__))
         "SimplifyCFG is not yet capable of maintaining validity of a "(((!DTU || !DTU->hasPostDomTree()) && "SimplifyCFG is not yet capable of maintaining validity of a "
 "PostDomTree, so don't ask for it.") ? static_cast<void>
 (0) : __assert_fail ("(!DTU || !DTU->hasPostDomTree()) && \"SimplifyCFG is not yet capable of maintaining validity of a \" \"PostDomTree, so don't ask for it.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 270, __PRETTY_FUNCTION__))
         "PostDomTree, so don't ask for it.")(((!DTU || !DTU->hasPostDomTree()) && "SimplifyCFG is not yet capable of maintaining validity of a "
 "PostDomTree, so don't ask for it.") ? static_cast<void>
 (0) : __assert_fail ("(!DTU || !DTU->hasPostDomTree()) && \"SimplifyCFG is not yet capable of maintaining validity of a \" \"PostDomTree, so don't ask for it.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 270, __PRETTY_FUNCTION__));
}

bool simplifyOnce(BasicBlock *BB);
bool simplifyOnceImpl(BasicBlock *BB);
bool run(BasicBlock *BB);

// Helper to set Resimplify and return change indication.
bool requestResimplify() {
  Resimplify = true;
  return true;
}
282};

284} // end anonymous namespace

286/// Return true if it is safe to merge these two
287/// terminator instructions together.
288static bool
289SafeToMergeTerminators(Instruction *SI1, Instruction *SI2,
                     SmallSetVector<BasicBlock *, 4> *FailBlocks = nullptr) {
if (SI1 == SI2)
50
←
Assuming 'SI1' is not equal to 'SI2'→
51
←
Taking false branch→
  return false; // Can't merge with self!

// It is not safe to merge these two switch instructions if they have a common
// successor, and if that successor has a PHI node, and if *that* PHI node has
// conflicting incoming values from the two switch blocks.
BasicBlock *SI1BB = SI1->getParent();
BasicBlock *SI2BB = SI2->getParent();

SmallPtrSet<BasicBlock *, 16> SI1Succs(succ_begin(SI1BB), succ_end(SI1BB));
bool Fail = false;
for (BasicBlock *Succ : successors(SI2BB))
  if (SI1Succs.count(Succ))
    for (BasicBlock::iterator BBI = Succ->begin(); isa<PHINode>(BBI); ++BBI) {
      PHINode *PN = cast<PHINode>(BBI);
      if (PN->getIncomingValueForBlock(SI1BB) !=
          PN->getIncomingValueForBlock(SI2BB)) {
        if (FailBlocks)
          FailBlocks->insert(Succ);
        Fail = true;
      }
    }

return !Fail;
52
←
Returning the value 1, which participates in a condition later→
315}

317/// Return true if it is safe and profitable to merge these two terminator
318/// instructions together, where SI1 is an unconditional branch. PhiNodes will
319/// store all PHI nodes in common successors.
320static bool
321isProfitableToFoldUnconditional(BranchInst *SI1, BranchInst *SI2,
                              Instruction *Cond,
                              SmallVectorImpl<PHINode *> &PhiNodes) {
if (SI1 == SI2)
  return false; // Can't merge with self!
assert(SI1->isUnconditional() && SI2->isConditional())((SI1->isUnconditional() && SI2->isConditional(
)) ? static_cast<void> (0) : __assert_fail ("SI1->isUnconditional() && SI2->isConditional()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 326, __PRETTY_FUNCTION__));

// We fold the unconditional branch if we can easily update all PHI nodes in
// common successors:
// 1> We have a constant incoming value for the conditional branch;
// 2> We have "Cond" as the incoming value for the unconditional branch;
// 3> SI2->getCondition() and Cond have same operands.
CmpInst *Ci2 = dyn_cast<CmpInst>(SI2->getCondition());
if (!Ci2)
  return false;
if (!(Cond->getOperand(0) == Ci2->getOperand(0) &&
      Cond->getOperand(1) == Ci2->getOperand(1)) &&
    !(Cond->getOperand(0) == Ci2->getOperand(1) &&
      Cond->getOperand(1) == Ci2->getOperand(0)))
  return false;

BasicBlock *SI1BB = SI1->getParent();
BasicBlock *SI2BB = SI2->getParent();
SmallPtrSet<BasicBlock *, 16> SI1Succs(succ_begin(SI1BB), succ_end(SI1BB));
for (BasicBlock *Succ : successors(SI2BB))
  if (SI1Succs.count(Succ))
    for (BasicBlock::iterator BBI = Succ->begin(); isa<PHINode>(BBI); ++BBI) {
      PHINode *PN = cast<PHINode>(BBI);
      if (PN->getIncomingValueForBlock(SI1BB) != Cond ||
          !isa<ConstantInt>(PN->getIncomingValueForBlock(SI2BB)))
        return false;
      PhiNodes.push_back(PN);
    }
return true;
355}

357/// Update PHI nodes in Succ to indicate that there will now be entries in it
358/// from the 'NewPred' block. The values that will be flowing into the PHI nodes
359/// will be the same as those coming in from ExistPred, an existing predecessor
360/// of Succ.
361static void AddPredecessorToBlock(BasicBlock *Succ, BasicBlock *NewPred,
                                BasicBlock *ExistPred,
                                MemorySSAUpdater *MSSAU = nullptr) {
for (PHINode &PN : Succ->phis())
  PN.addIncoming(PN.getIncomingValueForBlock(ExistPred), NewPred);
if (MSSAU)
  if (auto *MPhi = MSSAU->getMemorySSA()->getMemoryAccess(Succ))
    MPhi->addIncoming(MPhi->getIncomingValueForBlock(ExistPred), NewPred);
369}

371/// Compute an abstract "cost" of speculating the given instruction,
372/// which is assumed to be safe to speculate. TCC_Free means cheap,
373/// TCC_Basic means less cheap, and TCC_Expensive means prohibitively
374/// expensive.
375static unsigned ComputeSpeculationCost(const User *I,
                                     const TargetTransformInfo &TTI) {
assert(isSafeToSpeculativelyExecute(I) &&((isSafeToSpeculativelyExecute(I) && "Instruction is not safe to speculatively execute!"
) ? static_cast<void> (0) : __assert_fail ("isSafeToSpeculativelyExecute(I) && \"Instruction is not safe to speculatively execute!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 378, __PRETTY_FUNCTION__))
       "Instruction is not safe to speculatively execute!")((isSafeToSpeculativelyExecute(I) && "Instruction is not safe to speculatively execute!"
) ? static_cast<void> (0) : __assert_fail ("isSafeToSpeculativelyExecute(I) && \"Instruction is not safe to speculatively execute!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 378, __PRETTY_FUNCTION__));
return TTI.getUserCost(I, TargetTransformInfo::TCK_SizeAndLatency);
380}

382/// If we have a merge point of an "if condition" as accepted above,
383/// return true if the specified value dominates the block.  We
384/// don't handle the true generality of domination here, just a special case
385/// which works well enough for us.
386///
387/// If AggressiveInsts is non-null, and if V does not dominate BB, we check to
388/// see if V (which must be an instruction) and its recursive operands
389/// that do not dominate BB have a combined cost lower than CostRemaining and
390/// are non-trapping.  If both are true, the instruction is inserted into the
391/// set and true is returned.
392///
393/// The cost for most non-trapping instructions is defined as 1 except for
394/// Select whose cost is 2.
395///
396/// After this function returns, CostRemaining is decreased by the cost of
397/// V plus its non-dominating operands.  If that cost is greater than
398/// CostRemaining, false is returned and CostRemaining is undefined.
399static bool DominatesMergePoint(Value *V, BasicBlock *BB,
                              SmallPtrSetImpl<Instruction *> &AggressiveInsts,
                              int &BudgetRemaining,
                              const TargetTransformInfo &TTI,
                              unsigned Depth = 0) {
// It is possible to hit a zero-cost cycle (phi/gep instructions for example),
// so limit the recursion depth.
// TODO: While this recursion limit does prevent pathological behavior, it
// would be better to track visited instructions to avoid cycles.
if (Depth == MaxSpeculationDepth)
  return false;

Instruction *I = dyn_cast<Instruction>(V);
if (!I) {
  // Non-instructions all dominate instructions, but not all constantexprs
  // can be executed unconditionally.
  if (ConstantExpr *C = dyn_cast<ConstantExpr>(V))
    if (C->canTrap())
      return false;
  return true;
}
BasicBlock *PBB = I->getParent();

// We don't want to allow weird loops that might have the "if condition" in
// the bottom of this block.
if (PBB == BB)
  return false;

// If this instruction is defined in a block that contains an unconditional
// branch to BB, then it must be in the 'conditional' part of the "if
// statement".  If not, it definitely dominates the region.
BranchInst *BI = dyn_cast<BranchInst>(PBB->getTerminator());
if (!BI || BI->isConditional() || BI->getSuccessor(0) != BB)
  return true;

// If we have seen this instruction before, don't count it again.
if (AggressiveInsts.count(I))
  return true;

// Okay, it looks like the instruction IS in the "condition".  Check to
// see if it's a cheap instruction to unconditionally compute, and if it
// only uses stuff defined outside of the condition.  If so, hoist it out.
if (!isSafeToSpeculativelyExecute(I))
  return false;

BudgetRemaining -= ComputeSpeculationCost(I, TTI);

// Allow exactly one instruction to be speculated regardless of its cost
// (as long as it is safe to do so).
// This is intended to flatten the CFG even if the instruction is a division
// or other expensive operation. The speculation of an expensive instruction
// is expected to be undone in CodeGenPrepare if the speculation has not
// enabled further IR optimizations.
if (BudgetRemaining < 0 &&
    (!SpeculateOneExpensiveInst || !AggressiveInsts.empty() || Depth > 0))
  return false;

// Okay, we can only really hoist these out if their operands do
// not take us over the cost threshold.
for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i)
  if (!DominatesMergePoint(*i, BB, AggressiveInsts, BudgetRemaining, TTI,
                           Depth + 1))
    return false;
// Okay, it's safe to do this!  Remember this instruction.
AggressiveInsts.insert(I);
return true;
465}

467/// Extract ConstantInt from value, looking through IntToPtr
468/// and PointerNullValue. Return NULL if value is not a constant int.
469static ConstantInt *GetConstantInt(Value *V, const DataLayout &DL) {
// Normal constant int.
ConstantInt *CI = dyn_cast<ConstantInt>(V);
if (CI || !isa<Constant>(V) || !V->getType()->isPointerTy())
  return CI;

// This is some kind of pointer constant. Turn it into a pointer-sized
// ConstantInt if possible.
IntegerType *PtrTy = cast<IntegerType>(DL.getIntPtrType(V->getType()));

// Null pointer means 0, see SelectionDAGBuilder::getValue(const Value*).
if (isa<ConstantPointerNull>(V))
  return ConstantInt::get(PtrTy, 0);

// IntToPtr const int.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
  if (CE->getOpcode() == Instruction::IntToPtr)
    if (ConstantInt *CI = dyn_cast<ConstantInt>(CE->getOperand(0))) {
      // The constant is very likely to have the right type already.
      if (CI->getType() == PtrTy)
        return CI;
      else
        return cast<ConstantInt>(
            ConstantExpr::getIntegerCast(CI, PtrTy, /*isSigned=*/false));
    }
return nullptr;
495}

497namespace {

499/// Given a chain of or (||) or and (&&) comparison of a value against a
500/// constant, this will try to recover the information required for a switch
501/// structure.
502/// It will depth-first traverse the chain of comparison, seeking for patterns
503/// like %a == 12 or %a < 4 and combine them to produce a set of integer
504/// representing the different cases for the switch.
505/// Note that if the chain is composed of '||' it will build the set of elements
506/// that matches the comparisons (i.e. any of this value validate the chain)
507/// while for a chain of '&&' it will build the set elements that make the test
508/// fail.
509struct ConstantComparesGatherer {
const DataLayout &DL;

/// Value found for the switch comparison
Value *CompValue = nullptr;

/// Extra clause to be checked before the switch
Value *Extra = nullptr;

/// Set of integers to match in switch
SmallVector<ConstantInt *, 8> Vals;

/// Number of comparisons matched in the and/or chain
unsigned UsedICmps = 0;

/// Construct and compute the result for the comparison instruction Cond
ConstantComparesGatherer(Instruction *Cond, const DataLayout &DL) : DL(DL) {
  gather(Cond);
}

ConstantComparesGatherer(const ConstantComparesGatherer &) = delete;
ConstantComparesGatherer &
operator=(const ConstantComparesGatherer &) = delete;

533private:
/// Try to set the current value used for the comparison, it succeeds only if
/// it wasn't set before or if the new value is the same as the old one
bool setValueOnce(Value *NewVal) {
  if (CompValue && CompValue != NewVal)
    return false;
  CompValue = NewVal;
  return (CompValue != nullptr);
}

/// Try to match Instruction "I" as a comparison against a constant and
/// populates the array Vals with the set of values that match (or do not
/// match depending on isEQ).
/// Return false on failure. On success, the Value the comparison matched
/// against is placed in CompValue.
/// If CompValue is already set, the function is expected to fail if a match
/// is found but the value compared to is different.
bool matchInstruction(Instruction *I, bool isEQ) {
  // If this is an icmp against a constant, handle this as one of the cases.
  ICmpInst *ICI;
  ConstantInt *C;
  if (!((ICI = dyn_cast<ICmpInst>(I)) &&
        (C = GetConstantInt(I->getOperand(1), DL)))) {
    return false;
  }

  Value *RHSVal;
  const APInt *RHSC;

  // Pattern match a special case
  // (x & ~2^z) == y --> x == y || x == y|2^z
  // This undoes a transformation done by instcombine to fuse 2 compares.
  if (ICI->getPredicate() == (isEQ ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE)) {
    // It's a little bit hard to see why the following transformations are
    // correct. Here is a CVC3 program to verify them for 64-bit values:

    /*
       ONE  : BITVECTOR(64) = BVZEROEXTEND(0bin1, 63);
       x    : BITVECTOR(64);
       y    : BITVECTOR(64);
       z    : BITVECTOR(64);
       mask : BITVECTOR(64) = BVSHL(ONE, z);
       QUERY( (y & ~mask = y) =>
              ((x & ~mask = y) <=> (x = y OR x = (y |  mask)))
       );
       QUERY( (y |  mask = y) =>
              ((x |  mask = y) <=> (x = y OR x = (y & ~mask)))
       );
    */

    // Please note that each pattern must be a dual implication (<--> or
    // iff). One directional implication can create spurious matches. If the
    // implication is only one-way, an unsatisfiable condition on the left
    // side can imply a satisfiable condition on the right side. Dual
    // implication ensures that satisfiable conditions are transformed to
    // other satisfiable conditions and unsatisfiable conditions are
    // transformed to other unsatisfiable conditions.

    // Here is a concrete example of a unsatisfiable condition on the left
    // implying a satisfiable condition on the right:
    //
    // mask = (1 << z)
    // (x & ~mask) == y  --> (x == y || x == (y | mask))
    //
    // Substituting y = 3, z = 0 yields:
    // (x & -2) == 3 --> (x == 3 || x == 2)

    // Pattern match a special case:
    /*
      QUERY( (y & ~mask = y) =>
             ((x & ~mask = y) <=> (x = y OR x = (y |  mask)))
      );
    */
    if (match(ICI->getOperand(0),
              m_And(m_Value(RHSVal), m_APInt(RHSC)))) {
      APInt Mask = ~*RHSC;
      if (Mask.isPowerOf2() && (C->getValue() & ~Mask) == C->getValue()) {
        // If we already have a value for the switch, it has to match!
        if (!setValueOnce(RHSVal))
          return false;

        Vals.push_back(C);
        Vals.push_back(
            ConstantInt::get(C->getContext(),
                             C->getValue() | Mask));
        UsedICmps++;
        return true;
      }
    }

    // Pattern match a special case:
    /*
      QUERY( (y |  mask = y) =>
             ((x |  mask = y) <=> (x = y OR x = (y & ~mask)))
      );
    */
    if (match(ICI->getOperand(0),
              m_Or(m_Value(RHSVal), m_APInt(RHSC)))) {
      APInt Mask = *RHSC;
      if (Mask.isPowerOf2() && (C->getValue() | Mask) == C->getValue()) {
        // If we already have a value for the switch, it has to match!
        if (!setValueOnce(RHSVal))
          return false;

        Vals.push_back(C);
        Vals.push_back(ConstantInt::get(C->getContext(),
                                        C->getValue() & ~Mask));
        UsedICmps++;
        return true;
      }
    }

    // If we already have a value for the switch, it has to match!
    if (!setValueOnce(ICI->getOperand(0)))
      return false;

    UsedICmps++;
    Vals.push_back(C);
    return ICI->getOperand(0);
  }

  // If we have "x ult 3", for example, then we can add 0,1,2 to the set.
  ConstantRange Span = ConstantRange::makeAllowedICmpRegion(
      ICI->getPredicate(), C->getValue());

  // Shift the range if the compare is fed by an add. This is the range
  // compare idiom as emitted by instcombine.
  Value *CandidateVal = I->getOperand(0);
  if (match(I->getOperand(0), m_Add(m_Value(RHSVal), m_APInt(RHSC)))) {
    Span = Span.subtract(*RHSC);
    CandidateVal = RHSVal;
  }

  // If this is an and/!= check, then we are looking to build the set of
  // value that *don't* pass the and chain. I.e. to turn "x ugt 2" into
  // x != 0 && x != 1.
  if (!isEQ)
    Span = Span.inverse();

  // If there are a ton of values, we don't want to make a ginormous switch.
  if (Span.isSizeLargerThan(8) || Span.isEmptySet()) {
    return false;
  }

  // If we already have a value for the switch, it has to match!
  if (!setValueOnce(CandidateVal))
    return false;

  // Add all values from the range to the set
  for (APInt Tmp = Span.getLower(); Tmp != Span.getUpper(); ++Tmp)
    Vals.push_back(ConstantInt::get(I->getContext(), Tmp));

  UsedICmps++;
  return true;
}

/// Given a potentially 'or'd or 'and'd together collection of icmp
/// eq/ne/lt/gt instructions that compare a value against a constant, extract
/// the value being compared, and stick the list constants into the Vals
/// vector.
/// One "Extra" case is allowed to differ from the other.
void gather(Value *V) {
  bool isEQ = match(V, m_LogicalOr(m_Value(), m_Value()));

  // Keep a stack (SmallVector for efficiency) for depth-first traversal
  SmallVector<Value *, 8> DFT;
  SmallPtrSet<Value *, 8> Visited;

  // Initialize
  Visited.insert(V);
  DFT.push_back(V);

  while (!DFT.empty()) {
    V = DFT.pop_back_val();

    if (Instruction *I = dyn_cast<Instruction>(V)) {
      // If it is a || (or && depending on isEQ), process the operands.
      Value *Op0, *Op1;
      if (isEQ ? match(I, m_LogicalOr(m_Value(Op0), m_Value(Op1)))
               : match(I, m_LogicalAnd(m_Value(Op0), m_Value(Op1)))) {
        if (Visited.insert(Op1).second)
          DFT.push_back(Op1);
        if (Visited.insert(Op0).second)
          DFT.push_back(Op0);

        continue;
      }

      // Try to match the current instruction
      if (matchInstruction(I, isEQ))
        // Match succeed, continue the loop
        continue;
    }

    // One element of the sequence of || (or &&) could not be match as a
    // comparison against the same value as the others.
    // We allow only one "Extra" case to be checked before the switch
    if (!Extra) {
      Extra = V;
      continue;
    }
    // Failed to parse a proper sequence, abort now
    CompValue = nullptr;
    break;
  }
}
739};

741} // end anonymous namespace

743static void EraseTerminatorAndDCECond(Instruction *TI,
                                    MemorySSAUpdater *MSSAU = nullptr) {
Instruction *Cond = nullptr;
if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
  Cond = dyn_cast<Instruction>(SI->getCondition());
} else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
  if (BI->isConditional())
    Cond = dyn_cast<Instruction>(BI->getCondition());
} else if (IndirectBrInst *IBI = dyn_cast<IndirectBrInst>(TI)) {
  Cond = dyn_cast<Instruction>(IBI->getAddress());
}

TI->eraseFromParent();
if (Cond)
  RecursivelyDeleteTriviallyDeadInstructions(Cond, nullptr, MSSAU);
758}

760/// Return true if the specified terminator checks
761/// to see if a value is equal to constant integer value.
762Value *SimplifyCFGOpt::isValueEqualityComparison(Instruction *TI) {
Value *CV = nullptr;
if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
  // Do not permit merging of large switch instructions into their
  // predecessors unless there is only one predecessor.
  if (!SI->getParent()->hasNPredecessorsOrMore(128 / SI->getNumSuccessors()))
    CV = SI->getCondition();
} else if (BranchInst *BI = dyn_cast<BranchInst>(TI))
  if (BI->isConditional() && BI->getCondition()->hasOneUse())
    if (ICmpInst *ICI = dyn_cast<ICmpInst>(BI->getCondition())) {
      if (ICI->isEquality() && GetConstantInt(ICI->getOperand(1), DL))
        CV = ICI->getOperand(0);
    }

// Unwrap any lossless ptrtoint cast.
if (CV) {
  if (PtrToIntInst *PTII = dyn_cast<PtrToIntInst>(CV)) {
    Value *Ptr = PTII->getPointerOperand();
    if (PTII->getType() == DL.getIntPtrType(Ptr->getType()))
      CV = Ptr;
  }
}
return CV;
785}

787/// Given a value comparison instruction,
788/// decode all of the 'cases' that it represents and return the 'default' block.
789BasicBlock *SimplifyCFGOpt::GetValueEqualityComparisonCases(
  Instruction *TI, std::vector<ValueEqualityComparisonCase> &Cases) {
if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
  Cases.reserve(SI->getNumCases());
  for (auto Case : SI->cases())
    Cases.push_back(ValueEqualityComparisonCase(Case.getCaseValue(),
                                                Case.getCaseSuccessor()));
  return SI->getDefaultDest();
}

BranchInst *BI = cast<BranchInst>(TI);
ICmpInst *ICI = cast<ICmpInst>(BI->getCondition());
BasicBlock *Succ = BI->getSuccessor(ICI->getPredicate() == ICmpInst::ICMP_NE);
Cases.push_back(ValueEqualityComparisonCase(
    GetConstantInt(ICI->getOperand(1), DL), Succ));
return BI->getSuccessor(ICI->getPredicate() == ICmpInst::ICMP_EQ);
805}

807/// Given a vector of bb/value pairs, remove any entries
808/// in the list that match the specified block.
809static void
810EliminateBlockCases(BasicBlock *BB,
                  std::vector<ValueEqualityComparisonCase> &Cases) {
llvm::erase_value(Cases, BB);
813}

815/// Return true if there are any keys in C1 that exist in C2 as well.
816static bool ValuesOverlap(std::vector<ValueEqualityComparisonCase> &C1,
                        std::vector<ValueEqualityComparisonCase> &C2) {
std::vector<ValueEqualityComparisonCase> *V1 = &C1, *V2 = &C2;

// Make V1 be smaller than V2.
if (V1->size() > V2->size())
  std::swap(V1, V2);

if (V1->empty())
  return false;
if (V1->size() == 1) {
  // Just scan V2.
  ConstantInt *TheVal = (*V1)[0].Value;
  for (unsigned i = 0, e = V2->size(); i != e; ++i)
    if (TheVal == (*V2)[i].Value)
      return true;
}

// Otherwise, just sort both lists and compare element by element.
array_pod_sort(V1->begin(), V1->end());
array_pod_sort(V2->begin(), V2->end());
unsigned i1 = 0, i2 = 0, e1 = V1->size(), e2 = V2->size();
while (i1 != e1 && i2 != e2) {
  if ((*V1)[i1].Value == (*V2)[i2].Value)
    return true;
  if ((*V1)[i1].Value < (*V2)[i2].Value)
    ++i1;
  else
    ++i2;
}
return false;
847}

849// Set branch weights on SwitchInst. This sets the metadata if there is at
850// least one non-zero weight.
851static void setBranchWeights(SwitchInst *SI, ArrayRef<uint32_t> Weights) {
// Check that there is at least one non-zero weight. Otherwise, pass
// nullptr to setMetadata which will erase the existing metadata.
MDNode *N = nullptr;
if (llvm::any_of(Weights, [](uint32_t W) { return W != 0; }))
  N = MDBuilder(SI->getParent()->getContext()).createBranchWeights(Weights);
SI->setMetadata(LLVMContext::MD_prof, N);
858}

860// Similar to the above, but for branch and select instructions that take
861// exactly 2 weights.
862static void setBranchWeights(Instruction *I, uint32_t TrueWeight,
                           uint32_t FalseWeight) {
assert(isa<BranchInst>(I) || isa<SelectInst>(I))((isa<BranchInst>(I) || isa<SelectInst>(I)) ? static_cast
<void> (0) : __assert_fail ("isa<BranchInst>(I) || isa<SelectInst>(I)"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 864, __PRETTY_FUNCTION__));
// Check that there is at least one non-zero weight. Otherwise, pass
// nullptr to setMetadata which will erase the existing metadata.
MDNode *N = nullptr;
if (TrueWeight || FalseWeight)
  N = MDBuilder(I->getParent()->getContext())
          .createBranchWeights(TrueWeight, FalseWeight);
I->setMetadata(LLVMContext::MD_prof, N);
872}

874/// If TI is known to be a terminator instruction and its block is known to
875/// only have a single predecessor block, check to see if that predecessor is
876/// also a value comparison with the same value, and if that comparison
877/// determines the outcome of this comparison. If so, simplify TI. This does a
878/// very limited form of jump threading.
879bool SimplifyCFGOpt::SimplifyEqualityComparisonWithOnlyPredecessor(
  Instruction *TI, BasicBlock *Pred, IRBuilder<> &Builder) {
Value *PredVal = isValueEqualityComparison(Pred->getTerminator());
if (!PredVal)
  return false; // Not a value comparison in predecessor.

Value *ThisVal = isValueEqualityComparison(TI);
assert(ThisVal && "This isn't a value comparison!!")((ThisVal && "This isn't a value comparison!!") ? static_cast
<void> (0) : __assert_fail ("ThisVal && \"This isn't a value comparison!!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 886, __PRETTY_FUNCTION__));
if (ThisVal != PredVal)
  return false; // Different predicates.

// TODO: Preserve branch weight metadata, similarly to how
// FoldValueComparisonIntoPredecessors preserves it.

// Find out information about when control will move from Pred to TI's block.
std::vector<ValueEqualityComparisonCase> PredCases;
BasicBlock *PredDef =
    GetValueEqualityComparisonCases(Pred->getTerminator(), PredCases);
EliminateBlockCases(PredDef, PredCases); // Remove default from cases.

// Find information about how control leaves this block.
std::vector<ValueEqualityComparisonCase> ThisCases;
BasicBlock *ThisDef = GetValueEqualityComparisonCases(TI, ThisCases);
EliminateBlockCases(ThisDef, ThisCases); // Remove default from cases.

// If TI's block is the default block from Pred's comparison, potentially
// simplify TI based on this knowledge.
if (PredDef == TI->getParent()) {
  // If we are here, we know that the value is none of those cases listed in
  // PredCases.  If there are any cases in ThisCases that are in PredCases, we
  // can simplify TI.
  if (!ValuesOverlap(PredCases, ThisCases))
    return false;

  if (isa<BranchInst>(TI)) {
    // Okay, one of the successors of this condbr is dead.  Convert it to a
    // uncond br.
    assert(ThisCases.size() == 1 && "Branch can only have one case!")((ThisCases.size() == 1 && "Branch can only have one case!"
) ? static_cast<void> (0) : __assert_fail ("ThisCases.size() == 1 && \"Branch can only have one case!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 916, __PRETTY_FUNCTION__));
    // Insert the new branch.
    Instruction *NI = Builder.CreateBr(ThisDef);
    (void)NI;

    // Remove PHI node entries for the dead edge.
    ThisCases[0].Dest->removePredecessor(PredDef);

    LLVM_DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI << "Leaving: " << *NI << "\n"; } } while
 (false)
                      << "Through successor TI: " << *TI << "Leaving: " << *NIdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI << "Leaving: " << *NI << "\n"; } } while
 (false)
                      << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI << "Leaving: " << *NI << "\n"; } } while
 (false);

    EraseTerminatorAndDCECond(TI);

    if (DTU)
      DTU->applyUpdates(
          {{DominatorTree::Delete, PredDef, ThisCases[0].Dest}});

    return true;
  }

  SwitchInstProfUpdateWrapper SI = *cast<SwitchInst>(TI);
  // Okay, TI has cases that are statically dead, prune them away.
  SmallPtrSet<Constant *, 16> DeadCases;
  for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
    DeadCases.insert(PredCases[i].Value);

  LLVM_DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI; } } while (false)
                    << "Through successor TI: " << *TI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI; } } while (false);

  SmallMapVector<BasicBlock *, int, 8> NumPerSuccessorCases;
  for (SwitchInst::CaseIt i = SI->case_end(), e = SI->case_begin(); i != e;) {
    --i;
    auto *Successor = i->getCaseSuccessor();
    ++NumPerSuccessorCases[Successor];
    if (DeadCases.count(i->getCaseValue())) {
      Successor->removePredecessor(PredDef);
      SI.removeCase(i);
      --NumPerSuccessorCases[Successor];
    }
  }

  std::vector<DominatorTree::UpdateType> Updates;
  for (const std::pair<BasicBlock *, int> &I : NumPerSuccessorCases)
    if (I.second == 0)
      Updates.push_back({DominatorTree::Delete, PredDef, I.first});
  if (DTU)
    DTU->applyUpdates(Updates);

  LLVM_DEBUG(dbgs() << "Leaving: " << *TI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Leaving: " << *TI <<
 "\n"; } } while (false);
  return true;
}

// Otherwise, TI's block must correspond to some matched value.  Find out
// which value (or set of values) this is.
ConstantInt *TIV = nullptr;
BasicBlock *TIBB = TI->getParent();
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
  if (PredCases[i].Dest == TIBB) {
    if (TIV)
      return false; // Cannot handle multiple values coming to this block.
    TIV = PredCases[i].Value;
  }
assert(TIV && "No edge from pred to succ?")((TIV && "No edge from pred to succ?") ? static_cast<
void> (0) : __assert_fail ("TIV && \"No edge from pred to succ?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 979, __PRETTY_FUNCTION__));

// Okay, we found the one constant that our value can be if we get into TI's
// BB.  Find out which successor will unconditionally be branched to.
BasicBlock *TheRealDest = nullptr;
for (unsigned i = 0, e = ThisCases.size(); i != e; ++i)
  if (ThisCases[i].Value == TIV) {
    TheRealDest = ThisCases[i].Dest;
    break;
  }

// If not handled by any explicit cases, it is handled by the default case.
if (!TheRealDest)
  TheRealDest = ThisDef;

SmallSetVector<BasicBlock *, 2> RemovedSuccs;

// Remove PHI node entries for dead edges.
BasicBlock *CheckEdge = TheRealDest;
for (BasicBlock *Succ : successors(TIBB))
  if (Succ != CheckEdge) {
    if (Succ != TheRealDest)
      RemovedSuccs.insert(Succ);
    Succ->removePredecessor(TIBB);
  } else
    CheckEdge = nullptr;

// Insert the new branch.
Instruction *NI = Builder.CreateBr(TheRealDest);
(void)NI;

LLVM_DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI << "Leaving: " << *NI << "\n"; } } while
 (false)
                  << "Through successor TI: " << *TI << "Leaving: " << *NIdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI << "Leaving: " << *NI << "\n"; } } while
 (false)
                  << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Threading pred instr: " <<
 *Pred->getTerminator() << "Through successor TI: " <<
 *TI << "Leaving: " << *NI << "\n"; } } while
 (false);

EraseTerminatorAndDCECond(TI);
if (DTU) {
  SmallVector<DominatorTree::UpdateType, 2> Updates;
  Updates.reserve(RemovedSuccs.size());
  for (auto *RemovedSucc : RemovedSuccs)
    Updates.push_back({DominatorTree::Delete, TIBB, RemovedSucc});
  DTU->applyUpdates(Updates);
}
return true;
1023}

1025namespace {

1027/// This class implements a stable ordering of constant
1028/// integers that does not depend on their address.  This is important for
1029/// applications that sort ConstantInt's to ensure uniqueness.
1030struct ConstantIntOrdering {
bool operator()(const ConstantInt *LHS, const ConstantInt *RHS) const {
  return LHS->getValue().ult(RHS->getValue());
}
1034};

1036} // end anonymous namespace

1038static int ConstantIntSortPredicate(ConstantInt *const *P1,
                                  ConstantInt *const *P2) {
const ConstantInt *LHS = *P1;
const ConstantInt *RHS = *P2;
if (LHS == RHS)
  return 0;
return LHS->getValue().ult(RHS->getValue()) ? 1 : -1;
1045}

1047static inline bool HasBranchWeights(const Instruction *I) {
MDNode *ProfMD = I->getMetadata(LLVMContext::MD_prof);
if (ProfMD && ProfMD->getOperand(0))
  if (MDString *MDS = dyn_cast<MDString>(ProfMD->getOperand(0)))
    return MDS->getString().equals("branch_weights");

return false;
1054}

1056/// Get Weights of a given terminator, the default weight is at the front
1057/// of the vector. If TI is a conditional eq, we need to swap the branch-weight
1058/// metadata.
1059static void GetBranchWeights(Instruction *TI,
                           SmallVectorImpl<uint64_t> &Weights) {
MDNode *MD = TI->getMetadata(LLVMContext::MD_prof);
assert(MD)((MD) ? static_cast<void> (0) : __assert_fail ("MD", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 1062, __PRETTY_FUNCTION__));
for (unsigned i = 1, e = MD->getNumOperands(); i < e; ++i) {
  ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(i));
  Weights.push_back(CI->getValue().getZExtValue());
}

// If TI is a conditional eq, the default case is the false case,
// and the corresponding branch-weight data is at index 2. We swap the
// default weight to be the first entry.
if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
  assert(Weights.size() == 2)((Weights.size() == 2) ? static_cast<void> (0) : __assert_fail
 ("Weights.size() == 2", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 1072, __PRETTY_FUNCTION__));
  ICmpInst *ICI = cast<ICmpInst>(BI->getCondition());
  if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
    std::swap(Weights.front(), Weights.back());
}
1077}

1079/// Keep halving the weights until all can fit in uint32_t.
1080static void FitWeights(MutableArrayRef<uint64_t> Weights) {
uint64_t Max = *std::max_element(Weights.begin(), Weights.end());
if (Max > UINT_MAX(2147483647 *2U +1U)) {
  unsigned Offset = 32 - countLeadingZeros(Max);
  for (uint64_t &I : Weights)
    I >>= Offset;
}
1087}

1089/// The specified terminator is a value equality comparison instruction
1090/// (either a switch or a branch on "X == c").
1091/// See if any of the predecessors of the terminator block are value comparisons
1092/// on the same value.  If so, and if safe to do so, fold them together.
1093bool SimplifyCFGOpt::FoldValueComparisonIntoPredecessors(Instruction *TI,
                                                       IRBuilder<> &Builder) {
BasicBlock *BB = TI->getParent();
Value *CV = isValueEqualityComparison(TI); // CondVal
assert(CV && "Not a comparison?")((CV && "Not a comparison?") ? static_cast<void>
 (0) : __assert_fail ("CV && \"Not a comparison?\"", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 1097, __PRETTY_FUNCTION__));

bool Changed = false;

auto _ = make_scope_exit([&]() {
  if (Changed)
    ++NumFoldValueComparisonIntoPredecessors;
});

SmallSetVector<BasicBlock *, 16> Preds(pred_begin(BB), pred_end(BB));
while (!Preds.empty()) {
  BasicBlock *Pred = Preds.pop_back_val();

  // See if the predecessor is a comparison with the same value.
  Instruction *PTI = Pred->getTerminator();
  Value *PCV = isValueEqualityComparison(PTI); // PredCondVal

  if (PCV == CV && TI != PTI) {
    SmallSetVector<BasicBlock*, 4> FailBlocks;
    if (!SafeToMergeTerminators(TI, PTI, &FailBlocks)) {
      for (auto *Succ : FailBlocks) {
        if (!SplitBlockPredecessors(Succ, TI->getParent(), ".fold.split",
                                    DTU))
          return false;
      }
    }

    std::vector<DominatorTree::UpdateType> Updates;

    // Figure out which 'cases' to copy from SI to PSI.
    std::vector<ValueEqualityComparisonCase> BBCases;
    BasicBlock *BBDefault = GetValueEqualityComparisonCases(TI, BBCases);

    std::vector<ValueEqualityComparisonCase> PredCases;
    BasicBlock *PredDefault = GetValueEqualityComparisonCases(PTI, PredCases);

    // Based on whether the default edge from PTI goes to BB or not, fill in
    // PredCases and PredDefault with the new switch cases we would like to
    // build.
    SmallMapVector<BasicBlock *, int, 8> NewSuccessors;

    // Update the branch weight metadata along the way
    SmallVector<uint64_t, 8> Weights;
    bool PredHasWeights = HasBranchWeights(PTI);
    bool SuccHasWeights = HasBranchWeights(TI);

    if (PredHasWeights) {
      GetBranchWeights(PTI, Weights);
      // branch-weight metadata is inconsistent here.
      if (Weights.size() != 1 + PredCases.size())
        PredHasWeights = SuccHasWeights = false;
    } else if (SuccHasWeights)
      // If there are no predecessor weights but there are successor weights,
      // populate Weights with 1, which will later be scaled to the sum of
      // successor's weights
      Weights.assign(1 + PredCases.size(), 1);

    SmallVector<uint64_t, 8> SuccWeights;
    if (SuccHasWeights) {
      GetBranchWeights(TI, SuccWeights);
      // branch-weight metadata is inconsistent here.
      if (SuccWeights.size() != 1 + BBCases.size())
        PredHasWeights = SuccHasWeights = false;
    } else if (PredHasWeights)
      SuccWeights.assign(1 + BBCases.size(), 1);

    if (PredDefault == BB) {
      // If this is the default destination from PTI, only the edges in TI
      // that don't occur in PTI, or that branch to BB will be activated.
      std::set<ConstantInt *, ConstantIntOrdering> PTIHandled;
      for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
        if (PredCases[i].Dest != BB)
          PTIHandled.insert(PredCases[i].Value);
        else {
          // The default destination is BB, we don't need explicit targets.
          std::swap(PredCases[i], PredCases.back());

          if (PredHasWeights || SuccHasWeights) {
            // Increase weight for the default case.
            Weights[0] += Weights[i + 1];
            std::swap(Weights[i + 1], Weights.back());
            Weights.pop_back();
          }

          PredCases.pop_back();
          --i;
          --e;
        }

      // Reconstruct the new switch statement we will be building.
      if (PredDefault != BBDefault) {
        PredDefault->removePredecessor(Pred);
        if (PredDefault != BB)
          Updates.push_back({DominatorTree::Delete, Pred, PredDefault});
        PredDefault = BBDefault;
        ++NewSuccessors[BBDefault];
      }

      unsigned CasesFromPred = Weights.size();
      uint64_t ValidTotalSuccWeight = 0;
      for (unsigned i = 0, e = BBCases.size(); i != e; ++i)
        if (!PTIHandled.count(BBCases[i].Value) &&
            BBCases[i].Dest != BBDefault) {
          PredCases.push_back(BBCases[i]);
          ++NewSuccessors[BBCases[i].Dest];
          if (SuccHasWeights || PredHasWeights) {
            // The default weight is at index 0, so weight for the ith case
            // should be at index i+1. Scale the cases from successor by
            // PredDefaultWeight (Weights[0]).
            Weights.push_back(Weights[0] * SuccWeights[i + 1]);
            ValidTotalSuccWeight += SuccWeights[i + 1];
          }
        }

      if (SuccHasWeights || PredHasWeights) {
        ValidTotalSuccWeight += SuccWeights[0];
        // Scale the cases from predecessor by ValidTotalSuccWeight.
        for (unsigned i = 1; i < CasesFromPred; ++i)
          Weights[i] *= ValidTotalSuccWeight;
        // Scale the default weight by SuccDefaultWeight (SuccWeights[0]).
        Weights[0] *= SuccWeights[0];
      }
    } else {
      // If this is not the default destination from PSI, only the edges
      // in SI that occur in PSI with a destination of BB will be
      // activated.
      std::set<ConstantInt *, ConstantIntOrdering> PTIHandled;
      std::map<ConstantInt *, uint64_t> WeightsForHandled;
      for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
        if (PredCases[i].Dest == BB) {
          PTIHandled.insert(PredCases[i].Value);

          if (PredHasWeights || SuccHasWeights) {
            WeightsForHandled[PredCases[i].Value] = Weights[i + 1];
            std::swap(Weights[i + 1], Weights.back());
            Weights.pop_back();
          }

          std::swap(PredCases[i], PredCases.back());
          PredCases.pop_back();
          --i;
          --e;
        }

      // Okay, now we know which constants were sent to BB from the
      // predecessor.  Figure out where they will all go now.
      for (unsigned i = 0, e = BBCases.size(); i != e; ++i)
        if (PTIHandled.count(BBCases[i].Value)) {
          // If this is one we are capable of getting...
          if (PredHasWeights || SuccHasWeights)
            Weights.push_back(WeightsForHandled[BBCases[i].Value]);
          PredCases.push_back(BBCases[i]);
          ++NewSuccessors[BBCases[i].Dest];
          PTIHandled.erase(
              BBCases[i].Value); // This constant is taken care of
        }

      // If there are any constants vectored to BB that TI doesn't handle,
      // they must go to the default destination of TI.
      for (ConstantInt *I : PTIHandled) {
        if (PredHasWeights || SuccHasWeights)
          Weights.push_back(WeightsForHandled[I]);
        PredCases.push_back(ValueEqualityComparisonCase(I, BBDefault));
        ++NewSuccessors[BBDefault];
      }
    }

    // Okay, at this point, we know which new successor Pred will get.  Make
    // sure we update the number of entries in the PHI nodes for these
    // successors.
    for (const std::pair<BasicBlock *, int /*Num*/> &NewSuccessor :
         NewSuccessors) {
      for (auto I : seq(0, NewSuccessor.second)) {
        (void)I;
        AddPredecessorToBlock(NewSuccessor.first, Pred, BB);
      }
      if (!is_contained(successors(Pred), NewSuccessor.first))
        Updates.push_back({DominatorTree::Insert, Pred, NewSuccessor.first});
    }

    Builder.SetInsertPoint(PTI);
    // Convert pointer to int before we switch.
    if (CV->getType()->isPointerTy()) {
      CV = Builder.CreatePtrToInt(CV, DL.getIntPtrType(CV->getType()),
                                  "magicptr");
    }

    // Now that the successors are updated, create the new Switch instruction.
    SwitchInst *NewSI =
        Builder.CreateSwitch(CV, PredDefault, PredCases.size());
    NewSI->setDebugLoc(PTI->getDebugLoc());
    for (ValueEqualityComparisonCase &V : PredCases)
      NewSI->addCase(V.Value, V.Dest);

    if (PredHasWeights || SuccHasWeights) {
      // Halve the weights if any of them cannot fit in an uint32_t
      FitWeights(Weights);

      SmallVector<uint32_t, 8> MDWeights(Weights.begin(), Weights.end());

      setBranchWeights(NewSI, MDWeights);
    }

    EraseTerminatorAndDCECond(PTI);

    // Okay, last check.  If BB is still a successor of PSI, then we must
    // have an infinite loop case.  If so, add an infinitely looping block
    // to handle the case to preserve the behavior of the code.
    BasicBlock *InfLoopBlock = nullptr;
    for (unsigned i = 0, e = NewSI->getNumSuccessors(); i != e; ++i)
      if (NewSI->getSuccessor(i) == BB) {
        if (!InfLoopBlock) {
          // Insert it at the end of the function, because it's either code,
          // or it won't matter if it's hot. :)
          InfLoopBlock = BasicBlock::Create(BB->getContext(), "infloop",
                                            BB->getParent());
          BranchInst::Create(InfLoopBlock, InfLoopBlock);
          Updates.push_back(
              {DominatorTree::Insert, InfLoopBlock, InfLoopBlock});
        }
        NewSI->setSuccessor(i, InfLoopBlock);
      }

    if (InfLoopBlock)
      Updates.push_back({DominatorTree::Insert, Pred, InfLoopBlock});

    Updates.push_back({DominatorTree::Delete, Pred, BB});

    if (DTU)
      DTU->applyUpdates(Updates);

    Changed = true;
  }
}
return Changed;
1332}

1334// If we would need to insert a select that uses the value of this invoke
1335// (comments in HoistThenElseCodeToIf explain why we would need to do this), we
1336// can't hoist the invoke, as there is nowhere to put the select in this case.
1337static bool isSafeToHoistInvoke(BasicBlock *BB1, BasicBlock *BB2,
                              Instruction *I1, Instruction *I2) {
for (BasicBlock *Succ : successors(BB1)) {
  for (const PHINode &PN : Succ->phis()) {
    Value *BB1V = PN.getIncomingValueForBlock(BB1);
    Value *BB2V = PN.getIncomingValueForBlock(BB2);
    if (BB1V != BB2V && (BB1V == I1 || BB2V == I2)) {
      return false;
    }
  }
}
return true;
1349}

1351static bool passingValueIsAlwaysUndefined(Value *V, Instruction *I, bool PtrValueMayBeModified = false);

1353/// Given a conditional branch that goes to BB1 and BB2, hoist any common code
1354/// in the two blocks up into the branch block. The caller of this function
1355/// guarantees that BI's block dominates BB1 and BB2.
1356bool SimplifyCFGOpt::HoistThenElseCodeToIf(BranchInst *BI,
                                         const TargetTransformInfo &TTI) {
// This does very trivial matching, with limited scanning, to find identical
// instructions in the two blocks.  In particular, we don't want to get into
// O(M*N) situations here where M and N are the sizes of BB1 and BB2.  As
// such, we currently just scan for obviously identical instructions in an
// identical order.
BasicBlock *BB1 = BI->getSuccessor(0); // The true destination.
BasicBlock *BB2 = BI->getSuccessor(1); // The false destination

BasicBlock::iterator BB1_Itr = BB1->begin();
BasicBlock::iterator BB2_Itr = BB2->begin();

Instruction *I1 = &*BB1_Itr++, *I2 = &*BB2_Itr++;
// Skip debug info if it is not identical.
DbgInfoIntrinsic *DBI1 = dyn_cast<DbgInfoIntrinsic>(I1);
DbgInfoIntrinsic *DBI2 = dyn_cast<DbgInfoIntrinsic>(I2);
if (!DBI1 || !DBI2 || !DBI1->isIdenticalToWhenDefined(DBI2)) {
  while (isa<DbgInfoIntrinsic>(I1))
    I1 = &*BB1_Itr++;
  while (isa<DbgInfoIntrinsic>(I2))
    I2 = &*BB2_Itr++;
}
// FIXME: Can we define a safety predicate for CallBr?
if (isa<PHINode>(I1) || !I1->isIdenticalToWhenDefined(I2) ||
    (isa<InvokeInst>(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2)) ||
    isa<CallBrInst>(I1))
  return false;

BasicBlock *BIParent = BI->getParent();

bool Changed = false;

auto _ = make_scope_exit([&]() {
  if (Changed)
    ++NumHoistCommonCode;
});

do {
  // If we are hoisting the terminator instruction, don't move one (making a
  // broken BB), instead clone it, and remove BI.
  if (I1->isTerminator())
    goto HoistTerminator;

  // If we're going to hoist a call, make sure that the two instructions we're
  // commoning/hoisting are both marked with musttail, or neither of them is
  // marked as such. Otherwise, we might end up in a situation where we hoist
  // from a block where the terminator is a `ret` to a block where the terminator
  // is a `br`, and `musttail` calls expect to be followed by a return.
  auto *C1 = dyn_cast<CallInst>(I1);
  auto *C2 = dyn_cast<CallInst>(I2);
  if (C1 && C2)
    if (C1->isMustTailCall() != C2->isMustTailCall())
      return Changed;

  if (!TTI.isProfitableToHoist(I1) || !TTI.isProfitableToHoist(I2))
    return Changed;

  // If any of the two call sites has nomerge attribute, stop hoisting.
  if (const auto *CB1 = dyn_cast<CallBase>(I1))
    if (CB1->cannotMerge())
      return Changed;
  if (const auto *CB2 = dyn_cast<CallBase>(I2))
    if (CB2->cannotMerge())
      return Changed;

  if (isa<DbgInfoIntrinsic>(I1) || isa<DbgInfoIntrinsic>(I2)) {
    assert (isa<DbgInfoIntrinsic>(I1) && isa<DbgInfoIntrinsic>(I2))((isa<DbgInfoIntrinsic>(I1) && isa<DbgInfoIntrinsic
>(I2)) ? static_cast<void> (0) : __assert_fail ("isa<DbgInfoIntrinsic>(I1) && isa<DbgInfoIntrinsic>(I2)"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 1423, __PRETTY_FUNCTION__));
    // The debug location is an integral part of a debug info intrinsic
    // and can't be separated from it or replaced.  Instead of attempting
    // to merge locations, simply hoist both copies of the intrinsic.
    BIParent->getInstList().splice(BI->getIterator(),
                                   BB1->getInstList(), I1);
    BIParent->getInstList().splice(BI->getIterator(),
                                   BB2->getInstList(), I2);
    Changed = true;
  } else {
    // For a normal instruction, we just move one to right before the branch,
    // then replace all uses of the other with the first.  Finally, we remove
    // the now redundant second instruction.
    BIParent->getInstList().splice(BI->getIterator(),
                                   BB1->getInstList(), I1);
    if (!I2->use_empty())
      I2->replaceAllUsesWith(I1);
    I1->andIRFlags(I2);
    unsigned KnownIDs[] = {LLVMContext::MD_tbaa,
                           LLVMContext::MD_range,
                           LLVMContext::MD_fpmath,
                           LLVMContext::MD_invariant_load,
                           LLVMContext::MD_nonnull,
                           LLVMContext::MD_invariant_group,
                           LLVMContext::MD_align,
                           LLVMContext::MD_dereferenceable,
                           LLVMContext::MD_dereferenceable_or_null,
                           LLVMContext::MD_mem_parallel_loop_access,
                           LLVMContext::MD_access_group,
                           LLVMContext::MD_preserve_access_index};
    combineMetadata(I1, I2, KnownIDs, true);

    // I1 and I2 are being combined into a single instruction.  Its debug
    // location is the merged locations of the original instructions.
    I1->applyMergedLocation(I1->getDebugLoc(), I2->getDebugLoc());

    I2->eraseFromParent();
    Changed = true;
  }
  ++NumHoistCommonInstrs;

  I1 = &*BB1_Itr++;
  I2 = &*BB2_Itr++;
  // Skip debug info if it is not identical.
  DbgInfoIntrinsic *DBI1 = dyn_cast<DbgInfoIntrinsic>(I1);
  DbgInfoIntrinsic *DBI2 = dyn_cast<DbgInfoIntrinsic>(I2);
  if (!DBI1 || !DBI2 || !DBI1->isIdenticalToWhenDefined(DBI2)) {
    while (isa<DbgInfoIntrinsic>(I1))
      I1 = &*BB1_Itr++;
    while (isa<DbgInfoIntrinsic>(I2))
      I2 = &*BB2_Itr++;
  }
} while (I1->isIdenticalToWhenDefined(I2));

return true;

1479HoistTerminator:
// It may not be possible to hoist an invoke.
// FIXME: Can we define a safety predicate for CallBr?
if (isa<InvokeInst>(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2))
  return Changed;

// TODO: callbr hoisting currently disabled pending further study.
if (isa<CallBrInst>(I1))
  return Changed;

for (BasicBlock *Succ : successors(BB1)) {
  for (PHINode &PN : Succ->phis()) {
    Value *BB1V = PN.getIncomingValueForBlock(BB1);
    Value *BB2V = PN.getIncomingValueForBlock(BB2);
    if (BB1V == BB2V)
      continue;

    // Check for passingValueIsAlwaysUndefined here because we would rather
    // eliminate undefined control flow then converting it to a select.
    if (passingValueIsAlwaysUndefined(BB1V, &PN) ||
        passingValueIsAlwaysUndefined(BB2V, &PN))
      return Changed;

    if (isa<ConstantExpr>(BB1V) && !isSafeToSpeculativelyExecute(BB1V))
      return Changed;
    if (isa<ConstantExpr>(BB2V) && !isSafeToSpeculativelyExecute(BB2V))
      return Changed;
  }
}

// Okay, it is safe to hoist the terminator.
Instruction *NT = I1->clone();
BIParent->getInstList().insert(BI->getIterator(), NT);
if (!NT->getType()->isVoidTy()) {
  I1->replaceAllUsesWith(NT);
  I2->replaceAllUsesWith(NT);
  NT->takeName(I1);
}
Changed = true;
++NumHoistCommonInstrs;

// Ensure terminator gets a debug location, even an unknown one, in case
// it involves inlinable calls.
NT->applyMergedLocation(I1->getDebugLoc(), I2->getDebugLoc());

// PHIs created below will adopt NT's merged DebugLoc.
IRBuilder<NoFolder> Builder(NT);

// Hoisting one of the terminators from our successor is a great thing.
// Unfortunately, the successors of the if/else blocks may have PHI nodes in
// them.  If they do, all PHI entries for BB1/BB2 must agree for all PHI
// nodes, so we insert select instruction to compute the final result.
std::map<std::pair<Value *, Value *>, SelectInst *> InsertedSelects;
for (BasicBlock *Succ : successors(BB1)) {
  for (PHINode &PN : Succ->phis()) {
    Value *BB1V = PN.getIncomingValueForBlock(BB1);
    Value *BB2V = PN.getIncomingValueForBlock(BB2);
    if (BB1V == BB2V)
      continue;

    // These values do not agree.  Insert a select instruction before NT
    // that determines the right value.
    SelectInst *&SI = InsertedSelects[std::make_pair(BB1V, BB2V)];
    if (!SI) {
      // Propagate fast-math-flags from phi node to its replacement select.
      IRBuilder<>::FastMathFlagGuard FMFGuard(Builder);
      if (isa<FPMathOperator>(PN))
        Builder.setFastMathFlags(PN.getFastMathFlags());

      SI = cast<SelectInst>(
          Builder.CreateSelect(BI->getCondition(), BB1V, BB2V,
                               BB1V->getName() + "." + BB2V->getName(), BI));
    }

    // Make the PHI node use the select for all incoming values for BB1/BB2
    for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
      if (PN.getIncomingBlock(i) == BB1 || PN.getIncomingBlock(i) == BB2)
        PN.setIncomingValue(i, SI);
  }
}

SmallVector<DominatorTree::UpdateType, 4> Updates;

// Update any PHI nodes in our new successors.
for (BasicBlock *Succ : successors(BB1)) {
  AddPredecessorToBlock(Succ, BIParent, BB1);
  Updates.push_back({DominatorTree::Insert, BIParent, Succ});
}
for (BasicBlock *Succ : successors(BI))
  Updates.push_back({DominatorTree::Delete, BIParent, Succ});

EraseTerminatorAndDCECond(BI);
if (DTU)
  DTU->applyUpdates(Updates);
return Changed;
1574}

1576// Check lifetime markers.
1577static bool isLifeTimeMarker(const Instruction *I) {
if (auto II = dyn_cast<IntrinsicInst>(I)) {
  switch (II->getIntrinsicID()) {
  default:
    break;
  case Intrinsic::lifetime_start:
  case Intrinsic::lifetime_end:
    return true;
  }
}
return false;
1588}

1590// TODO: Refine this. This should avoid cases like turning constant memcpy sizes
1591// into variables.
1592static bool replacingOperandWithVariableIsCheap(const Instruction *I,
                                              int OpIdx) {
return !isa<IntrinsicInst>(I);
1595}

1597// All instructions in Insts belong to different blocks that all unconditionally
1598// branch to a common successor. Analyze each instruction and return true if it
1599// would be possible to sink them into their successor, creating one common
1600// instruction instead. For every value that would be required to be provided by
1601// PHI node (because an operand varies in each input block), add to PHIOperands.
1602static bool canSinkInstructions(
  ArrayRef<Instruction *> Insts,
  DenseMap<Instruction *, SmallVector<Value *, 4>> &PHIOperands) {
// Prune out obviously bad instructions to move. Each instruction must have
// exactly zero or one use, and we check later that use is by a single, common
// PHI instruction in the successor.
bool HasUse = !Insts.front()->user_empty();
for (auto *I : Insts) {
  // These instructions may change or break semantics if moved.
  if (isa<PHINode>(I) || I->isEHPad() || isa<AllocaInst>(I) ||
      I->getType()->isTokenTy())
    return false;

  // Conservatively return false if I is an inline-asm instruction. Sinking
  // and merging inline-asm instructions can potentially create arguments
  // that cannot satisfy the inline-asm constraints.
  // If the instruction has nomerge attribute, return false.
  if (const auto *C = dyn_cast<CallBase>(I))
    if (C->isInlineAsm() || C->cannotMerge())
      return false;

  // Each instruction must have zero or one use.
  if (HasUse && !I->hasOneUse())
    return false;
  if (!HasUse && !I->user_empty())
    return false;
}

const Instruction *I0 = Insts.front();
for (auto *I : Insts)
  if (!I->isSameOperationAs(I0))
    return false;

// All instructions in Insts are known to be the same opcode. If they have a
// use, check that the only user is a PHI or in the same block as the
// instruction, because if a user is in the same block as an instruction we're
// contemplating sinking, it must already be determined to be sinkable.
if (HasUse) {
  auto *PNUse = dyn_cast<PHINode>(*I0->user_begin());
  auto *Succ = I0->getParent()->getTerminator()->getSuccessor(0);
  if (!all_of(Insts, [&PNUse,&Succ](const Instruction *I) -> bool {
        auto *U = cast<Instruction>(*I->user_begin());
        return (PNUse &&
                PNUse->getParent() == Succ &&
                PNUse->getIncomingValueForBlock(I->getParent()) == I) ||
               U->getParent() == I->getParent();
      }))
    return false;
}

// Because SROA can't handle speculating stores of selects, try not to sink
// loads, stores or lifetime markers of allocas when we'd have to create a
// PHI for the address operand. Also, because it is likely that loads or
// stores of allocas will disappear when Mem2Reg/SROA is run, don't sink
// them.
// This can cause code churn which can have unintended consequences down
// the line - see https://llvm.org/bugs/show_bug.cgi?id=30244.
// FIXME: This is a workaround for a deficiency in SROA - see
// https://llvm.org/bugs/show_bug.cgi?id=30188
if (isa<StoreInst>(I0) && any_of(Insts, [](const Instruction *I) {
      return isa<AllocaInst>(I->getOperand(1)->stripPointerCasts());
    }))
  return false;
if (isa<LoadInst>(I0) && any_of(Insts, [](const Instruction *I) {
      return isa<AllocaInst>(I->getOperand(0)->stripPointerCasts());
    }))
  return false;
if (isLifeTimeMarker(I0) && any_of(Insts, [](const Instruction *I) {
      return isa<AllocaInst>(I->getOperand(1)->stripPointerCasts());
    }))
  return false;

for (unsigned OI = 0, OE = I0->getNumOperands(); OI != OE; ++OI) {
  Value *Op = I0->getOperand(OI);
  if (Op->getType()->isTokenTy())
    // Don't touch any operand of token type.
    return false;

  auto SameAsI0 = [&I0, OI](const Instruction *I) {
    assert(I->getNumOperands() == I0->getNumOperands())((I->getNumOperands() == I0->getNumOperands()) ? static_cast
<void> (0) : __assert_fail ("I->getNumOperands() == I0->getNumOperands()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 1681, __PRETTY_FUNCTION__));
    return I->getOperand(OI) == I0->getOperand(OI);
  };
  if (!all_of(Insts, SameAsI0)) {
    if ((isa<Constant>(Op) && !replacingOperandWithVariableIsCheap(I0, OI)) ||
        !canReplaceOperandWithVariable(I0, OI))
      // We can't create a PHI from this GEP.
      return false;
    // Don't create indirect calls! The called value is the final operand.
    if (isa<CallBase>(I0) && OI == OE - 1) {
      // FIXME: if the call was *already* indirect, we should do this.
      return false;
    }
    for (auto *I : Insts)
      PHIOperands[I].push_back(I->getOperand(OI));
  }
}
return true;
1699}

1701// Assuming canSinkLastInstruction(Blocks) has returned true, sink the last
1702// instruction of every block in Blocks to their common successor, commoning
1703// into one instruction.
1704static bool sinkLastInstruction(ArrayRef<BasicBlock*> Blocks) {
auto *BBEnd = Blocks[0]->getTerminator()->getSuccessor(0);

// canSinkLastInstruction returning true guarantees that every block has at
// least one non-terminator instruction.
SmallVector<Instruction*,4> Insts;
for (auto *BB : Blocks) {
  Instruction *I = BB->getTerminator();
  do {
    I = I->getPrevNode();
  } while (isa<DbgInfoIntrinsic>(I) && I != &BB->front());
  if (!isa<DbgInfoIntrinsic>(I))
    Insts.push_back(I);
}

// The only checking we need to do now is that all users of all instructions
// are the same PHI node. canSinkLastInstruction should have checked this but
// it is slightly over-aggressive - it gets confused by commutative instructions
// so double-check it here.
Instruction *I0 = Insts.front();
if (!I0->user_empty()) {
  auto *PNUse = dyn_cast<PHINode>(*I0->user_begin());
  if (!all_of(Insts, [&PNUse](const Instruction *I) -> bool {
        auto *U = cast<Instruction>(*I->user_begin());
        return U == PNUse;
      }))
    return false;
}

// We don't need to do any more checking here; canSinkLastInstruction should
// have done it all for us.
SmallVector<Value*, 4> NewOperands;
for (unsigned O = 0, E = I0->getNumOperands(); O != E; ++O) {
  // This check is different to that in canSinkLastInstruction. There, we
  // cared about the global view once simplifycfg (and instcombine) have
  // completed - it takes into account PHIs that become trivially
  // simplifiable.  However here we need a more local view; if an operand
  // differs we create a PHI and rely on instcombine to clean up the very
  // small mess we may make.
  bool NeedPHI = any_of(Insts, [&I0, O](const Instruction *I) {
    return I->getOperand(O) != I0->getOperand(O);
  });
  if (!NeedPHI) {
    NewOperands.push_back(I0->getOperand(O));
    continue;
  }

  // Create a new PHI in the successor block and populate it.
  auto *Op = I0->getOperand(O);
  assert(!Op->getType()->isTokenTy() && "Can't PHI tokens!")((!Op->getType()->isTokenTy() && "Can't PHI tokens!"
) ? static_cast<void> (0) : __assert_fail ("!Op->getType()->isTokenTy() && \"Can't PHI tokens!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 1753, __PRETTY_FUNCTION__));
  auto *PN = PHINode::Create(Op->getType(), Insts.size(),
                             Op->getName() + ".sink", &BBEnd->front());
  for (auto *I : Insts)
    PN->addIncoming(I->getOperand(O), I->getParent());
  NewOperands.push_back(PN);
}

// Arbitrarily use I0 as the new "common" instruction; remap its operands
// and move it to the start of the successor block.
for (unsigned O = 0, E = I0->getNumOperands(); O != E; ++O)
  I0->getOperandUse(O).set(NewOperands[O]);
I0->moveBefore(&*BBEnd->getFirstInsertionPt());

// Update metadata and IR flags, and merge debug locations.
for (auto *I : Insts)
  if (I != I0) {
    // The debug location for the "common" instruction is the merged locations
    // of all the commoned instructions.  We start with the original location
    // of the "common" instruction and iteratively merge each location in the
    // loop below.
    // This is an N-way merge, which will be inefficient if I0 is a CallInst.
    // However, as N-way merge for CallInst is rare, so we use simplified API
    // instead of using complex API for N-way merge.
    I0->applyMergedLocation(I0->getDebugLoc(), I->getDebugLoc());
    combineMetadataForCSE(I0, I, true);
    I0->andIRFlags(I);
  }

if (!I0->user_empty()) {
  // canSinkLastInstruction checked that all instructions were used by
  // one and only one PHI node. Find that now, RAUW it to our common
  // instruction and nuke it.
  auto *PN = cast<PHINode>(*I0->user_begin());
  PN->replaceAllUsesWith(I0);
  PN->eraseFromParent();
}

// Finally nuke all instructions apart from the common instruction.
for (auto *I : Insts)
  if (I != I0)
    I->eraseFromParent();

return true;
1797}

1799namespace {

// LockstepReverseIterator - Iterates through instructions
// in a set of blocks in reverse order from the first non-terminator.
// For example (assume all blocks have size n):
//   LockstepReverseIterator I([B1, B2, B3]);
//   *I-- = [B1[n], B2[n], B3[n]];
//   *I-- = [B1[n-1], B2[n-1], B3[n-1]];
//   *I-- = [B1[n-2], B2[n-2], B3[n-2]];
//   ...
class LockstepReverseIterator {
  ArrayRef<BasicBlock*> Blocks;
  SmallVector<Instruction*,4> Insts;
  bool Fail;

public:
  LockstepReverseIterator(ArrayRef<BasicBlock*> Blocks) : Blocks(Blocks) {
    reset();
  }

  void reset() {
    Fail = false;
    Insts.clear();
    for (auto *BB : Blocks) {
      Instruction *Inst = BB->getTerminator();
      for (Inst = Inst->getPrevNode(); Inst && isa<DbgInfoIntrinsic>(Inst);)
        Inst = Inst->getPrevNode();
      if (!Inst) {
        // Block wasn't big enough.
        Fail = true;
        return;
      }
      Insts.push_back(Inst);
    }
  }

  bool isValid() const {
    return !Fail;
  }

  void operator--() {
    if (Fail)
      return;
    for (auto *&Inst : Insts) {
      for (Inst = Inst->getPrevNode(); Inst && isa<DbgInfoIntrinsic>(Inst);)
        Inst = Inst->getPrevNode();
      // Already at beginning of block.
      if (!Inst) {
        Fail = true;
        return;
      }
    }
  }

  ArrayRef<Instruction*> operator * () const {
    return Insts;
  }
};

1858} // end anonymous namespace

1860/// Check whether BB's predecessors end with unconditional branches. If it is
1861/// true, sink any common code from the predecessors to BB.
1862/// We also allow one predecessor to end with conditional branch (but no more
1863/// than one).
1864static bool SinkCommonCodeFromPredecessors(BasicBlock *BB,
                                         DomTreeUpdater *DTU) {
// We support two situations:
//   (1) all incoming arcs are unconditional
//   (2) one incoming arc is conditional
//
// (2) is very common in switch defaults and
// else-if patterns;
//
//   if (a) f(1);
//   else if (b) f(2);
//
// produces:
//
//       [if]
//      /    \
//    [f(1)] [if]
//      |     | \
//      |     |  |
//      |  [f(2)]|
//       \    | /
//        [ end ]
//
// [end] has two unconditional predecessor arcs and one conditional. The
// conditional refers to the implicit empty 'else' arc. This conditional
// arc can also be caused by an empty default block in a switch.
//
// In this case, we attempt to sink code from all *unconditional* arcs.
// If we can sink instructions from these arcs (determined during the scan
// phase below) we insert a common successor for all unconditional arcs and
// connect that to [end], to enable sinking:
//
//       [if]
//      /    \
//    [x(1)] [if]
//      |     | \
//      |     |  \
//      |  [x(2)] |
//       \   /    |
//   [sink.split] |
//         \     /
//         [ end ]
//
SmallVector<BasicBlock*,4> UnconditionalPreds;
Instruction *Cond = nullptr;
for (auto *B : predecessors(BB)) {
  auto *T = B->getTerminator();
  if (isa<BranchInst>(T) && cast<BranchInst>(T)->isUnconditional())
    UnconditionalPreds.push_back(B);
  else if ((isa<BranchInst>(T) || isa<SwitchInst>(T)) && !Cond)
    Cond = T;
  else
    return false;
}
if (UnconditionalPreds.size() < 2)
  return false;

// We take a two-step approach to tail sinking. First we scan from the end of
// each block upwards in lockstep. If the n'th instruction from the end of each
// block can be sunk, those instructions are added to ValuesToSink and we
// carry on. If we can sink an instruction but need to PHI-merge some operands
// (because they're not identical in each instruction) we add these to
// PHIOperands.
unsigned ScanIdx = 0;
SmallPtrSet<Value*,4> InstructionsToSink;
DenseMap<Instruction*, SmallVector<Value*,4>> PHIOperands;
LockstepReverseIterator LRI(UnconditionalPreds);
while (LRI.isValid() &&
       canSinkInstructions(*LRI, PHIOperands)) {
  LLVM_DEBUG(dbgs() << "SINK: instruction can be sunk: " << *(*LRI)[0]do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: instruction can be sunk: "
 << *(*LRI)[0] << "\n"; } } while (false)
                    << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: instruction can be sunk: "
 << *(*LRI)[0] << "\n"; } } while (false);
  InstructionsToSink.insert((*LRI).begin(), (*LRI).end());
  ++ScanIdx;
  --LRI;
}

// If no instructions can be sunk, early-return.
if (ScanIdx == 0)
  return false;

bool Changed = false;

auto ProfitableToSinkInstruction = [&](LockstepReverseIterator &LRI) {
  unsigned NumPHIdValues = 0;
  for (auto *I : *LRI)
    for (auto *V : PHIOperands[I])
      if (InstructionsToSink.count(V) == 0)
        ++NumPHIdValues;
  LLVM_DEBUG(dbgs() << "SINK: #phid values: " << NumPHIdValues << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: #phid values: " <<
 NumPHIdValues << "\n"; } } while (false);
  unsigned NumPHIInsts = NumPHIdValues / UnconditionalPreds.size();
  if ((NumPHIdValues % UnconditionalPreds.size()) != 0)
      NumPHIInsts++;

  return NumPHIInsts <= 1;
};

if (Cond) {
  // Check if we would actually sink anything first! This mutates the CFG and
  // adds an extra block. The goal in doing this is to allow instructions that
  // couldn't be sunk before to be sunk - obviously, speculatable instructions
  // (such as trunc, add) can be sunk and predicated already. So we check that
  // we're going to sink at least one non-speculatable instruction.
  LRI.reset();
  unsigned Idx = 0;
  bool Profitable = false;
  while (ProfitableToSinkInstruction(LRI) && Idx < ScanIdx) {
    if (!isSafeToSpeculativelyExecute((*LRI)[0])) {
      Profitable = true;
      break;
    }
    --LRI;
    ++Idx;
  }
  if (!Profitable)
    return false;

  LLVM_DEBUG(dbgs() << "SINK: Splitting edge\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: Splitting edge\n"; }
 } while (false);
  // We have a conditional edge and we're going to sink some instructions.
  // Insert a new block postdominating all blocks we're going to sink from.
  if (!SplitBlockPredecessors(BB, UnconditionalPreds, ".sink.split", DTU))
    // Edges couldn't be split.
    return false;
  Changed = true;
}

// Now that we've analyzed all potential sinking candidates, perform the
// actual sink. We iteratively sink the last non-terminator of the source
// blocks into their common successor unless doing so would require too
// many PHI instructions to be generated (currently only one PHI is allowed
// per sunk instruction).
//
// We can use InstructionsToSink to discount values needing PHI-merging that will
// actually be sunk in a later iteration. This allows us to be more
// aggressive in what we sink. This does allow a false positive where we
// sink presuming a later value will also be sunk, but stop half way through
// and never actually sink it which means we produce more PHIs than intended.
// This is unlikely in practice though.
unsigned SinkIdx = 0;
for (; SinkIdx != ScanIdx; ++SinkIdx) {
  LLVM_DEBUG(dbgs() << "SINK: Sink: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: Sink: " << *UnconditionalPreds
[0]->getTerminator()->getPrevNode() << "\n"; } } while
 (false)
                    << *UnconditionalPreds[0]->getTerminator()->getPrevNode()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: Sink: " << *UnconditionalPreds
[0]->getTerminator()->getPrevNode() << "\n"; } } while
 (false)
                    << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: Sink: " << *UnconditionalPreds
[0]->getTerminator()->getPrevNode() << "\n"; } } while
 (false);

  // Because we've sunk every instruction in turn, the current instruction to
  // sink is always at index 0.
  LRI.reset();
  if (!ProfitableToSinkInstruction(LRI)) {
    // Too many PHIs would be created.
    LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: stopping here, too many PHIs would be created!\n"
; } } while (false)
        dbgs() << "SINK: stopping here, too many PHIs would be created!\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: stopping here, too many PHIs would be created!\n"
; } } while (false);
    break;
  }

  if (!sinkLastInstruction(UnconditionalPreds)) {
    LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: stopping here, failed to actually sink instruction!\n"
; } } while (false)
        dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: stopping here, failed to actually sink instruction!\n"
; } } while (false)
        << "SINK: stopping here, failed to actually sink instruction!\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SINK: stopping here, failed to actually sink instruction!\n"
; } } while (false);
    break;
  }

  NumSinkCommonInstrs++;
  Changed = true;
}
if (SinkIdx != 0)
  ++NumSinkCommonCode;
return Changed;
2030}

2032/// Determine if we can hoist sink a sole store instruction out of a
2033/// conditional block.
2034///
2035/// We are looking for code like the following:
2036///   BrBB:
2037///     store i32 %add, i32* %arrayidx2
2038///     ... // No other stores or function calls (we could be calling a memory
2039///     ... // function).
2040///     %cmp = icmp ult %x, %y
2041///     br i1 %cmp, label %EndBB, label %ThenBB
2042///   ThenBB:
2043///     store i32 %add5, i32* %arrayidx2
2044///     br label EndBB
2045///   EndBB:
2046///     ...
2047///   We are going to transform this into:
2048///   BrBB:
2049///     store i32 %add, i32* %arrayidx2
2050///     ... //
2051///     %cmp = icmp ult %x, %y
2052///     %add.add5 = select i1 %cmp, i32 %add, %add5
2053///     store i32 %add.add5, i32* %arrayidx2
2054///     ...
2055///
2056/// \return The pointer to the value of the previous store if the store can be
2057///         hoisted into the predecessor block. 0 otherwise.
2058static Value *isSafeToSpeculateStore(Instruction *I, BasicBlock *BrBB,
                                   BasicBlock *StoreBB, BasicBlock *EndBB) {
StoreInst *StoreToHoist = dyn_cast<StoreInst>(I);
if (!StoreToHoist)
  return nullptr;

// Volatile or atomic.
if (!StoreToHoist->isSimple())
  return nullptr;

Value *StorePtr = StoreToHoist->getPointerOperand();

// Look for a store to the same pointer in BrBB.
unsigned MaxNumInstToLookAt = 9;
// Skip pseudo probe intrinsic calls which are not really killing any memory
// accesses.
for (Instruction &CurI : reverse(BrBB->instructionsWithoutDebug(true))) {
  if (!MaxNumInstToLookAt)
    break;
  --MaxNumInstToLookAt;

  // Could be calling an instruction that affects memory like free().
  if (CurI.mayHaveSideEffects() && !isa<StoreInst>(CurI))
    return nullptr;

  if (auto *SI = dyn_cast<StoreInst>(&CurI)) {
    // Found the previous store make sure it stores to the same location.
    if (SI->getPointerOperand() == StorePtr)
      // Found the previous store, return its value operand.
      return SI->getValueOperand();
    return nullptr; // Unknown store.
  }
}

return nullptr;
2093}

2095/// Estimate the cost of the insertion(s) and check that the PHI nodes can be
2096/// converted to selects.
2097static bool validateAndCostRequiredSelects(BasicBlock *BB, BasicBlock *ThenBB,
                                         BasicBlock *EndBB,
                                         unsigned &SpeculatedInstructions,
                                         int &BudgetRemaining,
                                         const TargetTransformInfo &TTI) {
TargetTransformInfo::TargetCostKind CostKind =
  BB->getParent()->hasMinSize()
  ? TargetTransformInfo::TCK_CodeSize
  : TargetTransformInfo::TCK_SizeAndLatency;

bool HaveRewritablePHIs = false;
for (PHINode &PN : EndBB->phis()) {
  Value *OrigV = PN.getIncomingValueForBlock(BB);
  Value *ThenV = PN.getIncomingValueForBlock(ThenBB);

  // FIXME: Try to remove some of the duplication with HoistThenElseCodeToIf.
  // Skip PHIs which are trivial.
  if (ThenV == OrigV)
    continue;

  BudgetRemaining -=
      TTI.getCmpSelInstrCost(Instruction::Select, PN.getType(), nullptr,
                             CmpInst::BAD_ICMP_PREDICATE, CostKind);

  // Don't convert to selects if we could remove undefined behavior instead.
  if (passingValueIsAlwaysUndefined(OrigV, &PN) ||
      passingValueIsAlwaysUndefined(ThenV, &PN))
    return false;

  HaveRewritablePHIs = true;
  ConstantExpr *OrigCE = dyn_cast<ConstantExpr>(OrigV);
  ConstantExpr *ThenCE = dyn_cast<ConstantExpr>(ThenV);
  if (!OrigCE && !ThenCE)
    continue; // Known safe and cheap.

  if ((ThenCE && !isSafeToSpeculativelyExecute(ThenCE)) ||
      (OrigCE && !isSafeToSpeculativelyExecute(OrigCE)))
    return false;
  unsigned OrigCost = OrigCE ? ComputeSpeculationCost(OrigCE, TTI) : 0;
  unsigned ThenCost = ThenCE ? ComputeSpeculationCost(ThenCE, TTI) : 0;
  unsigned MaxCost =
      2 * PHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic;
  if (OrigCost + ThenCost > MaxCost)
    return false;

  // Account for the cost of an unfolded ConstantExpr which could end up
  // getting expanded into Instructions.
  // FIXME: This doesn't account for how many operations are combined in the
  // constant expression.
  ++SpeculatedInstructions;
  if (SpeculatedInstructions > 1)
    return false;
}

return HaveRewritablePHIs;
2152}

2154/// Speculate a conditional basic block flattening the CFG.
2155///
2156/// Note that this is a very risky transform currently. Speculating
2157/// instructions like this is most often not desirable. Instead, there is an MI
2158/// pass which can do it with full awareness of the resource constraints.
2159/// However, some cases are "obvious" and we should do directly. An example of
2160/// this is speculating a single, reasonably cheap instruction.
2161///
2162/// There is only one distinct advantage to flattening the CFG at the IR level:
2163/// it makes very common but simplistic optimizations such as are common in
2164/// instcombine and the DAG combiner more powerful by removing CFG edges and
2165/// modeling their effects with easier to reason about SSA value graphs.
2166///
2167///
2168/// An illustration of this transform is turning this IR:
2169/// \code
2170///   BB:
2171///     %cmp = icmp ult %x, %y
2172///     br i1 %cmp, label %EndBB, label %ThenBB
2173///   ThenBB:
2174///     %sub = sub %x, %y
2175///     br label BB2
2176///   EndBB:
2177///     %phi = phi [ %sub, %ThenBB ], [ 0, %EndBB ]
2178///     ...
2179/// \endcode
2180///
2181/// Into this IR:
2182/// \code
2183///   BB:
2184///     %cmp = icmp ult %x, %y
2185///     %sub = sub %x, %y
2186///     %cond = select i1 %cmp, 0, %sub
2187///     ...
2188/// \endcode
2189///
2190/// \returns true if the conditional block is removed.
2191bool SimplifyCFGOpt::SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *ThenBB,
                                          const TargetTransformInfo &TTI) {
// Be conservative for now. FP select instruction can often be expensive.
Value *BrCond = BI->getCondition();
if (isa<FCmpInst>(BrCond))
  return false;

BasicBlock *BB = BI->getParent();
BasicBlock *EndBB = ThenBB->getTerminator()->getSuccessor(0);
int BudgetRemaining =
  PHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic;

// If ThenBB is actually on the false edge of the conditional branch, remember
// to swap the select operands later.
bool Invert = false;
if (ThenBB != BI->getSuccessor(0)) {
  assert(ThenBB == BI->getSuccessor(1) && "No edge from 'if' block?")((ThenBB == BI->getSuccessor(1) && "No edge from 'if' block?"
) ? static_cast<void> (0) : __assert_fail ("ThenBB == BI->getSuccessor(1) && \"No edge from 'if' block?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 2207, __PRETTY_FUNCTION__));
  Invert = true;
}
assert(EndBB == BI->getSuccessor(!Invert) && "No edge from to end block")((EndBB == BI->getSuccessor(!Invert) && "No edge from to end block"
) ? static_cast<void> (0) : __assert_fail ("EndBB == BI->getSuccessor(!Invert) && \"No edge from to end block\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 2210, __PRETTY_FUNCTION__));

// Keep a count of how many times instructions are used within ThenBB when
// they are candidates for sinking into ThenBB. Specifically:
// - They are defined in BB, and
// - They have no side effects, and
// - All of their uses are in ThenBB.
SmallDenseMap<Instruction *, unsigned, 4> SinkCandidateUseCounts;

SmallVector<Instruction *, 4> SpeculatedDbgIntrinsics;

unsigned SpeculatedInstructions = 0;
Value *SpeculatedStoreValue = nullptr;
StoreInst *SpeculatedStore = nullptr;
for (BasicBlock::iterator BBI = ThenBB->begin(),
                          BBE = std::prev(ThenBB->end());
     BBI != BBE; ++BBI) {
  Instruction *I = &*BBI;
  // Skip debug info.
  if (isa<DbgInfoIntrinsic>(I)) {
    SpeculatedDbgIntrinsics.push_back(I);
    continue;
  }

  // Skip pseudo probes. The consequence is we lose track of the branch
  // probability for ThenBB, which is fine since the optimization here takes
  // place regardless of the branch probability.
  if (isa<PseudoProbeInst>(I)) {
    SpeculatedDbgIntrinsics.push_back(I);
    continue;
  }

  // Only speculatively execute a single instruction (not counting the
  // terminator) for now.
  ++SpeculatedInstructions;
  if (SpeculatedInstructions > 1)
    return false;

  // Don't hoist the instruction if it's unsafe or expensive.
  if (!isSafeToSpeculativelyExecute(I) &&
      !(HoistCondStores && (SpeculatedStoreValue = isSafeToSpeculateStore(
                                I, BB, ThenBB, EndBB))))
    return false;
  if (!SpeculatedStoreValue &&
      ComputeSpeculationCost(I, TTI) >
          PHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic)
    return false;

  // Store the store speculation candidate.
  if (SpeculatedStoreValue)
    SpeculatedStore = cast<StoreInst>(I);

  // Do not hoist the instruction if any of its operands are defined but not
  // used in BB. The transformation will prevent the operand from
  // being sunk into the use block.
  for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i) {
    Instruction *OpI = dyn_cast<Instruction>(*i);
    if (!OpI || OpI->getParent() != BB || OpI->mayHaveSideEffects())
      continue; // Not a candidate for sinking.

    ++SinkCandidateUseCounts[OpI];
  }
}

// Consider any sink candidates which are only used in ThenBB as costs for
// speculation. Note, while we iterate over a DenseMap here, we are summing
// and so iteration order isn't significant.
for (SmallDenseMap<Instruction *, unsigned, 4>::iterator
         I = SinkCandidateUseCounts.begin(),
         E = SinkCandidateUseCounts.end();
     I != E; ++I)
  if (I->first->hasNUses(I->second)) {
    ++SpeculatedInstructions;
    if (SpeculatedInstructions > 1)
      return false;
  }

// Check that we can insert the selects and that it's not too expensive to do
// so.
bool Convert = SpeculatedStore != nullptr;
Convert |= validateAndCostRequiredSelects(BB, ThenBB, EndBB,
                                          SpeculatedInstructions,
                                          BudgetRemaining, TTI);
if (!Convert || BudgetRemaining < 0)
  return false;

// If we get here, we can hoist the instruction and if-convert.
LLVM_DEBUG(dbgs() << "SPECULATIVELY EXECUTING BB" << *ThenBB << "\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SPECULATIVELY EXECUTING BB"
 << *ThenBB << "\n";; } } while (false);

// Insert a select of the value of the speculated store.
if (SpeculatedStoreValue) {
  IRBuilder<NoFolder> Builder(BI);
  Value *TrueV = SpeculatedStore->getValueOperand();
  Value *FalseV = SpeculatedStoreValue;
  if (Invert)
    std::swap(TrueV, FalseV);
  Value *S = Builder.CreateSelect(
      BrCond, TrueV, FalseV, "spec.store.select", BI);
  SpeculatedStore->setOperand(0, S);
  SpeculatedStore->applyMergedLocation(BI->getDebugLoc(),
                                       SpeculatedStore->getDebugLoc());
}

// Metadata can be dependent on the condition we are hoisting above.
// Conservatively strip all metadata on the instruction. Drop the debug loc
// to avoid making it appear as if the condition is a constant, which would
// be misleading while debugging.
for (auto &I : *ThenBB) {
  if (!SpeculatedStoreValue || &I != SpeculatedStore)
    I.setDebugLoc(DebugLoc());
  I.dropUnknownNonDebugMetadata();
}

// Hoist the instructions.
BB->getInstList().splice(BI->getIterator(), ThenBB->getInstList(),
                         ThenBB->begin(), std::prev(ThenBB->end()));

// Insert selects and rewrite the PHI operands.
IRBuilder<NoFolder> Builder(BI);
for (PHINode &PN : EndBB->phis()) {
  unsigned OrigI = PN.getBasicBlockIndex(BB);
  unsigned ThenI = PN.getBasicBlockIndex(ThenBB);
  Value *OrigV = PN.getIncomingValue(OrigI);
  Value *ThenV = PN.getIncomingValue(ThenI);

  // Skip PHIs which are trivial.
  if (OrigV == ThenV)
    continue;

  // Create a select whose true value is the speculatively executed value and
  // false value is the pre-existing value. Swap them if the branch
  // destinations were inverted.
  Value *TrueV = ThenV, *FalseV = OrigV;
  if (Invert)
    std::swap(TrueV, FalseV);
  Value *V = Builder.CreateSelect(BrCond, TrueV, FalseV, "spec.select", BI);
  PN.setIncomingValue(OrigI, V);
  PN.setIncomingValue(ThenI, V);
}

// Remove speculated dbg intrinsics.
// FIXME: Is it possible to do this in a more elegant way? Moving/merging the
// dbg value for the different flows and inserting it after the select.
for (Instruction *I : SpeculatedDbgIntrinsics)
  I->eraseFromParent();

++NumSpeculations;
return true;
2358}

2360/// Return true if we can thread a branch across this block.
2361static bool BlockIsSimpleEnoughToThreadThrough(BasicBlock *BB) {
int Size = 0;

for (Instruction &I : BB->instructionsWithoutDebug()) {
  if (Size > MaxSmallBlockSize)
    return false; // Don't clone large BB's.

  // Can't fold blocks that contain noduplicate or convergent calls.
  if (CallInst *CI = dyn_cast<CallInst>(&I))
    if (CI->cannotDuplicate() || CI->isConvergent())
      return false;

  // We will delete Phis while threading, so Phis should not be accounted in
  // block's size
  if (!isa<PHINode>(I))
    ++Size;

  // We can only support instructions that do not define values that are
  // live outside of the current basic block.
  for (User *U : I.users()) {
    Instruction *UI = cast<Instruction>(U);
    if (UI->getParent() != BB || isa<PHINode>(UI))
      return false;
  }

  // Looks ok, continue checking.
}

return true;
2390}

2392/// If we have a conditional branch on a PHI node value that is defined in the
2393/// same block as the branch and if any PHI entries are constants, thread edges
2394/// corresponding to that entry to be branches to their ultimate destination.
2395static bool FoldCondBranchOnPHI(BranchInst *BI, DomTreeUpdater *DTU,
                              const DataLayout &DL, AssumptionCache *AC) {
BasicBlock *BB = BI->getParent();
PHINode *PN = dyn_cast<PHINode>(BI->getCondition());
// NOTE: we currently cannot transform this case if the PHI node is used
// outside of the block.
if (!PN || PN->getParent() != BB || !PN->hasOneUse())
  return false;

// Degenerate case of a single entry PHI.
if (PN->getNumIncomingValues() == 1) {
  FoldSingleEntryPHINodes(PN->getParent());
  return true;
}

// Now we know that this block has multiple preds and two succs.
if (!BlockIsSimpleEnoughToThreadThrough(BB))
  return false;

// Okay, this is a simple enough basic block.  See if any phi values are
// constants.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
  ConstantInt *CB = dyn_cast<ConstantInt>(PN->getIncomingValue(i));
  if (!CB || !CB->getType()->isIntegerTy(1))
    continue;

  // Okay, we now know that all edges from PredBB should be revectored to
  // branch to RealDest.
  BasicBlock *PredBB = PN->getIncomingBlock(i);
  BasicBlock *RealDest = BI->getSuccessor(!CB->getZExtValue());

  if (RealDest == BB)
    continue; // Skip self loops.
  // Skip if the predecessor's terminator is an indirect branch.
  if (isa<IndirectBrInst>(PredBB->getTerminator()))
    continue;

  SmallVector<DominatorTree::UpdateType, 3> Updates;

  // The dest block might have PHI nodes, other predecessors and other
  // difficult cases.  Instead of being smart about this, just insert a new
  // block that jumps to the destination block, effectively splitting
  // the edge we are about to create.
  BasicBlock *EdgeBB =
      BasicBlock::Create(BB->getContext(), RealDest->getName() + ".critedge",
                         RealDest->getParent(), RealDest);
  BranchInst *CritEdgeBranch = BranchInst::Create(RealDest, EdgeBB);
  Updates.push_back({DominatorTree::Insert, EdgeBB, RealDest});
  CritEdgeBranch->setDebugLoc(BI->getDebugLoc());

  // Update PHI nodes.
  AddPredecessorToBlock(RealDest, EdgeBB, BB);

  // BB may have instructions that are being threaded over.  Clone these
  // instructions into EdgeBB.  We know that there will be no uses of the
  // cloned instructions outside of EdgeBB.
  BasicBlock::iterator InsertPt = EdgeBB->begin();
  DenseMap<Value *, Value *> TranslateMap; // Track translated values.
  for (BasicBlock::iterator BBI = BB->begin(); &*BBI != BI; ++BBI) {
    if (PHINode *PN = dyn_cast<PHINode>(BBI)) {
      TranslateMap[PN] = PN->getIncomingValueForBlock(PredBB);
      continue;
    }
    // Clone the instruction.
    Instruction *N = BBI->clone();
    if (BBI->hasName())
      N->setName(BBI->getName() + ".c");

    // Update operands due to translation.
    for (User::op_iterator i = N->op_begin(), e = N->op_end(); i != e; ++i) {
      DenseMap<Value *, Value *>::iterator PI = TranslateMap.find(*i);
      if (PI != TranslateMap.end())
        *i = PI->second;
    }

    // Check for trivial simplification.
    if (Value *V = SimplifyInstruction(N, {DL, nullptr, nullptr, AC})) {
      if (!BBI->use_empty())
        TranslateMap[&*BBI] = V;
      if (!N->mayHaveSideEffects()) {
        N->deleteValue(); // Instruction folded away, don't need actual inst
        N = nullptr;
      }
    } else {
      if (!BBI->use_empty())
        TranslateMap[&*BBI] = N;
    }
    if (N) {
      // Insert the new instruction into its new home.
      EdgeBB->getInstList().insert(InsertPt, N);

      // Register the new instruction with the assumption cache if necessary.
      if (AC && match(N, m_Intrinsic<Intrinsic::assume>()))
        AC->registerAssumption(cast<IntrinsicInst>(N));
    }
  }

  // Loop over all of the edges from PredBB to BB, changing them to branch
  // to EdgeBB instead.
  Instruction *PredBBTI = PredBB->getTerminator();
  for (unsigned i = 0, e = PredBBTI->getNumSuccessors(); i != e; ++i)
    if (PredBBTI->getSuccessor(i) == BB) {
      BB->removePredecessor(PredBB);
      PredBBTI->setSuccessor(i, EdgeBB);
    }

  Updates.push_back({DominatorTree::Insert, PredBB, EdgeBB});
  Updates.push_back({DominatorTree::Delete, PredBB, BB});

  if (DTU)
    DTU->applyUpdates(Updates);

  // Recurse, simplifying any other constants.
  return FoldCondBranchOnPHI(BI, DTU, DL, AC) || true;
}

return false;
2512}

2514/// Given a BB that starts with the specified two-entry PHI node,
2515/// see if we can eliminate it.
2516static bool FoldTwoEntryPHINode(PHINode *PN, const TargetTransformInfo &TTI,
                              DomTreeUpdater *DTU, const DataLayout &DL) {
// Ok, this is a two entry PHI node.  Check to see if this is a simple "if
// statement", which has a very simple dominance structure.  Basically, we
// are trying to find the condition that is being branched on, which
// subsequently causes this merge to happen.  We really want control
// dependence information for this check, but simplifycfg can't keep it up
// to date, and this catches most of the cases we care about anyway.
BasicBlock *BB = PN->getParent();

BasicBlock *IfTrue, *IfFalse;
Value *IfCond = GetIfCondition(BB, IfTrue, IfFalse);
if (!IfCond ||
    // Don't bother if the branch will be constant folded trivially.
    isa<ConstantInt>(IfCond))
  return false;

// Okay, we found that we can merge this two-entry phi node into a select.
// Doing so would require us to fold *all* two entry phi nodes in this block.
// At some point this becomes non-profitable (particularly if the target
// doesn't support cmov's).  Only do this transformation if there are two or
// fewer PHI nodes in this block.
unsigned NumPhis = 0;
for (BasicBlock::iterator I = BB->begin(); isa<PHINode>(I); ++NumPhis, ++I)
  if (NumPhis > 2)
    return false;

// Loop over the PHI's seeing if we can promote them all to select
// instructions.  While we are at it, keep track of the instructions
// that need to be moved to the dominating block.
SmallPtrSet<Instruction *, 4> AggressiveInsts;
int BudgetRemaining =
    TwoEntryPHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic;

bool Changed = false;
for (BasicBlock::iterator II = BB->begin(); isa<PHINode>(II);) {
  PHINode *PN = cast<PHINode>(II++);
  if (Value *V = SimplifyInstruction(PN, {DL, PN})) {
    PN->replaceAllUsesWith(V);
    PN->eraseFromParent();
    Changed = true;
    continue;
  }

  if (!DominatesMergePoint(PN->getIncomingValue(0), BB, AggressiveInsts,
                           BudgetRemaining, TTI) ||
      !DominatesMergePoint(PN->getIncomingValue(1), BB, AggressiveInsts,
                           BudgetRemaining, TTI))
    return Changed;
}

// If we folded the first phi, PN dangles at this point.  Refresh it.  If
// we ran out of PHIs then we simplified them all.
PN = dyn_cast<PHINode>(BB->begin());
if (!PN)
  return true;

// Return true if at least one of these is a 'not', and another is either
// a 'not' too, or a constant.
auto CanHoistNotFromBothValues = [](Value *V0, Value *V1) {
  if (!match(V0, m_Not(m_Value())))
    std::swap(V0, V1);
  auto Invertible = m_CombineOr(m_Not(m_Value()), m_AnyIntegralConstant());
  return match(V0, m_Not(m_Value())) && match(V1, Invertible);
};

// Don't fold i1 branches on PHIs which contain binary operators, unless one
// of the incoming values is an 'not' and another one is freely invertible.
// These can often be turned into switches and other things.
if (PN->getType()->isIntegerTy(1) &&
    (isa<BinaryOperator>(PN->getIncomingValue(0)) ||
     isa<BinaryOperator>(PN->getIncomingValue(1)) ||
     isa<BinaryOperator>(IfCond)) &&
    !CanHoistNotFromBothValues(PN->getIncomingValue(0),
                               PN->getIncomingValue(1)))
  return Changed;

// If all PHI nodes are promotable, check to make sure that all instructions
// in the predecessor blocks can be promoted as well. If not, we won't be able
// to get rid of the control flow, so it's not worth promoting to select
// instructions.
BasicBlock *DomBlock = nullptr;
BasicBlock *IfBlock1 = PN->getIncomingBlock(0);
BasicBlock *IfBlock2 = PN->getIncomingBlock(1);
if (cast<BranchInst>(IfBlock1->getTerminator())->isConditional()) {
  IfBlock1 = nullptr;
} else {
  DomBlock = *pred_begin(IfBlock1);
  for (BasicBlock::iterator I = IfBlock1->begin(); !I->isTerminator(); ++I)
    if (!AggressiveInsts.count(&*I) && !isa<DbgInfoIntrinsic>(I) &&
        !isa<PseudoProbeInst>(I)) {
      // This is not an aggressive instruction that we can promote.
      // Because of this, we won't be able to get rid of the control flow, so
      // the xform is not worth it.
      return Changed;
    }
}

if (cast<BranchInst>(IfBlock2->getTerminator())->isConditional()) {
  IfBlock2 = nullptr;
} else {
  DomBlock = *pred_begin(IfBlock2);
  for (BasicBlock::iterator I = IfBlock2->begin(); !I->isTerminator(); ++I)
    if (!AggressiveInsts.count(&*I) && !isa<DbgInfoIntrinsic>(I) &&
        !isa<PseudoProbeInst>(I)) {
      // This is not an aggressive instruction that we can promote.
      // Because of this, we won't be able to get rid of the control flow, so
      // the xform is not worth it.
      return Changed;
    }
}
assert(DomBlock && "Failed to find root DomBlock")((DomBlock && "Failed to find root DomBlock") ? static_cast
<void> (0) : __assert_fail ("DomBlock && \"Failed to find root DomBlock\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 2627, __PRETTY_FUNCTION__));

LLVM_DEBUG(dbgs() << "FOUND IF CONDITION!  " << *IfConddo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOUND IF CONDITION!  " <<
 *IfCond << "  T: " << IfTrue->getName() <<
 "  F: " << IfFalse->getName() << "\n"; } } while
 (false)
                  << "  T: " << IfTrue->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOUND IF CONDITION!  " <<
 *IfCond << "  T: " << IfTrue->getName() <<
 "  F: " << IfFalse->getName() << "\n"; } } while
 (false)
                  << "  F: " << IfFalse->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOUND IF CONDITION!  " <<
 *IfCond << "  T: " << IfTrue->getName() <<
 "  F: " << IfFalse->getName() << "\n"; } } while
 (false);

// If we can still promote the PHI nodes after this gauntlet of tests,
// do all of the PHI's now.
Instruction *InsertPt = DomBlock->getTerminator();
IRBuilder<NoFolder> Builder(InsertPt);

// Move all 'aggressive' instructions, which are defined in the
// conditional parts of the if's up to the dominating block.
if (IfBlock1)
  hoistAllInstructionsInto(DomBlock, InsertPt, IfBlock1);
if (IfBlock2)
  hoistAllInstructionsInto(DomBlock, InsertPt, IfBlock2);

// Propagate fast-math-flags from phi nodes to replacement selects.
IRBuilder<>::FastMathFlagGuard FMFGuard(Builder);
while (PHINode *PN = dyn_cast<PHINode>(BB->begin())) {
  if (isa<FPMathOperator>(PN))
    Builder.setFastMathFlags(PN->getFastMathFlags());

  // Change the PHI node into a select instruction.
  Value *TrueVal = PN->getIncomingValue(PN->getIncomingBlock(0) == IfFalse);
  Value *FalseVal = PN->getIncomingValue(PN->getIncomingBlock(0) == IfTrue);

  Value *Sel = Builder.CreateSelect(IfCond, TrueVal, FalseVal, "", InsertPt);
  PN->replaceAllUsesWith(Sel);
  Sel->takeName(PN);
  PN->eraseFromParent();
}

// At this point, IfBlock1 and IfBlock2 are both empty, so our if statement
// has been flattened.  Change DomBlock to jump directly to our new block to
// avoid other simplifycfg's kicking in on the diamond.
Instruction *OldTI = DomBlock->getTerminator();
Builder.SetInsertPoint(OldTI);
Builder.CreateBr(BB);

SmallVector<DominatorTree::UpdateType, 3> Updates;
if (DTU) {
  Updates.push_back({DominatorTree::Insert, DomBlock, BB});
  for (auto *Successor : successors(DomBlock))
    Updates.push_back({DominatorTree::Delete, DomBlock, Successor});
}

OldTI->eraseFromParent();
if (DTU)
  DTU->applyUpdates(Updates);

return true;
2680}

2682/// If we found a conditional branch that goes to two returning blocks,
2683/// try to merge them together into one return,
2684/// introducing a select if the return values disagree.
2685bool SimplifyCFGOpt::SimplifyCondBranchToTwoReturns(BranchInst *BI,
                                                  IRBuilder<> &Builder) {
auto *BB = BI->getParent();
assert(BI->isConditional() && "Must be a conditional branch")((BI->isConditional() && "Must be a conditional branch"
) ? static_cast<void> (0) : __assert_fail ("BI->isConditional() && \"Must be a conditional branch\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 2688, __PRETTY_FUNCTION__));
BasicBlock *TrueSucc = BI->getSuccessor(0);
BasicBlock *FalseSucc = BI->getSuccessor(1);
// NOTE: destinations may match, this could be degenerate uncond branch.
ReturnInst *TrueRet = cast<ReturnInst>(TrueSucc->getTerminator());
ReturnInst *FalseRet = cast<ReturnInst>(FalseSucc->getTerminator());

// Check to ensure both blocks are empty (just a return) or optionally empty
// with PHI nodes.  If there are other instructions, merging would cause extra
// computation on one path or the other.
if (!TrueSucc->getFirstNonPHIOrDbg()->isTerminator())
  return false;
if (!FalseSucc->getFirstNonPHIOrDbg()->isTerminator())
  return false;

Builder.SetInsertPoint(BI);
// Okay, we found a branch that is going to two return nodes.  If
// there is no return value for this function, just change the
// branch into a return.
if (FalseRet->getNumOperands() == 0) {
  TrueSucc->removePredecessor(BB);
  FalseSucc->removePredecessor(BB);
  Builder.CreateRetVoid();
  EraseTerminatorAndDCECond(BI);
  if (DTU) {
    SmallVector<DominatorTree::UpdateType, 2> Updates;
    Updates.push_back({DominatorTree::Delete, BB, TrueSucc});
    if (TrueSucc != FalseSucc)
      Updates.push_back({DominatorTree::Delete, BB, FalseSucc});
    DTU->applyUpdates(Updates);
  }
  return true;
}

// Otherwise, figure out what the true and false return values are
// so we can insert a new select instruction.
Value *TrueValue = TrueRet->getReturnValue();
Value *FalseValue = FalseRet->getReturnValue();

// Unwrap any PHI nodes in the return blocks.
if (PHINode *TVPN = dyn_cast_or_null<PHINode>(TrueValue))
  if (TVPN->getParent() == TrueSucc)
    TrueValue = TVPN->getIncomingValueForBlock(BB);
if (PHINode *FVPN = dyn_cast_or_null<PHINode>(FalseValue))
  if (FVPN->getParent() == FalseSucc)
    FalseValue = FVPN->getIncomingValueForBlock(BB);

// In order for this transformation to be safe, we must be able to
// unconditionally execute both operands to the return.  This is
// normally the case, but we could have a potentially-trapping
// constant expression that prevents this transformation from being
// safe.
if (ConstantExpr *TCV = dyn_cast_or_null<ConstantExpr>(TrueValue))
  if (TCV->canTrap())
    return false;
if (ConstantExpr *FCV = dyn_cast_or_null<ConstantExpr>(FalseValue))
  if (FCV->canTrap())
    return false;

// Okay, we collected all the mapped values and checked them for sanity, and
// defined to really do this transformation.  First, update the CFG.
TrueSucc->removePredecessor(BB);
FalseSucc->removePredecessor(BB);

// Insert select instructions where needed.
Value *BrCond = BI->getCondition();
if (TrueValue) {
  // Insert a select if the results differ.
  if (TrueValue == FalseValue || isa<UndefValue>(FalseValue)) {
  } else if (isa<UndefValue>(TrueValue)) {
    TrueValue = FalseValue;
  } else {
    TrueValue =
        Builder.CreateSelect(BrCond, TrueValue, FalseValue, "retval", BI);
  }
}

Value *RI =
    !TrueValue ? Builder.CreateRetVoid() : Builder.CreateRet(TrueValue);

(void)RI;

LLVM_DEBUG(dbgs() << "\nCHANGING BRANCH TO TWO RETURNS INTO SELECT:"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "\nCHANGING BRANCH TO TWO RETURNS INTO SELECT:"
 << "\n  " << *BI << "\nNewRet = " <<
 *RI << "\nTRUEBLOCK: " << *TrueSucc << "\nFALSEBLOCK: "
 << *FalseSucc; } } while (false)
                  << "\n  " << *BI << "\nNewRet = " << *RI << "\nTRUEBLOCK: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "\nCHANGING BRANCH TO TWO RETURNS INTO SELECT:"
 << "\n  " << *BI << "\nNewRet = " <<
 *RI << "\nTRUEBLOCK: " << *TrueSucc << "\nFALSEBLOCK: "
 << *FalseSucc; } } while (false)
                  << *TrueSucc << "\nFALSEBLOCK: " << *FalseSucc)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "\nCHANGING BRANCH TO TWO RETURNS INTO SELECT:"
 << "\n  " << *BI << "\nNewRet = " <<
 *RI << "\nTRUEBLOCK: " << *TrueSucc << "\nFALSEBLOCK: "
 << *FalseSucc; } } while (false);

EraseTerminatorAndDCECond(BI);
if (DTU) {
  SmallVector<DominatorTree::UpdateType, 2> Updates;
  Updates.push_back({DominatorTree::Delete, BB, TrueSucc});
  if (TrueSucc != FalseSucc)
    Updates.push_back({DominatorTree::Delete, BB, FalseSucc});
  DTU->applyUpdates(Updates);
}

return true;
2784}

2786/// Return true if the given instruction is available
2787/// in its predecessor block. If yes, the instruction will be removed.
2788static bool tryCSEWithPredecessor(Instruction *Inst, BasicBlock *PB) {
if (!isa<BinaryOperator>(Inst) && !isa<CmpInst>(Inst))
  return false;
for (Instruction &I : *PB) {
  Instruction *PBI = &I;
  // Check whether Inst and PBI generate the same value.
  if (Inst->isIdenticalTo(PBI)) {
    Inst->replaceAllUsesWith(PBI);
    Inst->eraseFromParent();
    return true;
  }
}
return false;
2801}

2803/// Return true if either PBI or BI has branch weight available, and store
2804/// the weights in {Pred|Succ}{True|False}Weight. If one of PBI and BI does
2805/// not have branch weight, use 1:1 as its weight.
2806static bool extractPredSuccWeights(BranchInst *PBI, BranchInst *BI,
                                 uint64_t &PredTrueWeight,
                                 uint64_t &PredFalseWeight,
                                 uint64_t &SuccTrueWeight,
                                 uint64_t &SuccFalseWeight) {
bool PredHasWeights =
    PBI->extractProfMetadata(PredTrueWeight, PredFalseWeight);
bool SuccHasWeights =
    BI->extractProfMetadata(SuccTrueWeight, SuccFalseWeight);
if (PredHasWeights || SuccHasWeights) {
  if (!PredHasWeights)
    PredTrueWeight = PredFalseWeight = 1;
  if (!SuccHasWeights)
    SuccTrueWeight = SuccFalseWeight = 1;
  return true;
} else {
  return false;
}
2824}

2826/// If this basic block is simple enough, and if a predecessor branches to us
2827/// and one of our successors, fold the block into the predecessor and use
2828/// logical operations to pick the right destination.
2829bool llvm::FoldBranchToCommonDest(BranchInst *BI, DomTreeUpdater *DTU,
                                MemorySSAUpdater *MSSAU,
                                const TargetTransformInfo *TTI,
                                unsigned BonusInstThreshold) {
BasicBlock *BB = BI->getParent();

const unsigned PredCount = pred_size(BB);

bool Changed = false;

auto _ = make_scope_exit([&]() {
  if (Changed)
    ++NumFoldBranchToCommonDest;
});

TargetTransformInfo::TargetCostKind CostKind =
  BB->getParent()->hasMinSize() ? TargetTransformInfo::TCK_CodeSize
1
Assuming the condition is false→
2
←
'?' condition is false→
                                : TargetTransformInfo::TCK_SizeAndLatency;

Instruction *Cond = nullptr;
if (BI->isConditional())
3
←
Calling 'BranchInst::isConditional'→
6
←
Returning from 'BranchInst::isConditional'→
7
←
Taking true branch→
  Cond = dyn_cast<Instruction>(BI->getCondition());
8
←
Assuming the object is a 'Instruction'→
else {
  // For unconditional branch, check for a simple CFG pattern, where
  // BB has a single predecessor and BB's successor is also its predecessor's
  // successor. If such pattern exists, check for CSE between BB and its
  // predecessor.
  if (BasicBlock *PB = BB->getSinglePredecessor())
    if (BranchInst *PBI = dyn_cast<BranchInst>(PB->getTerminator()))
      if (PBI->isConditional() &&
          (BI->getSuccessor(0) == PBI->getSuccessor(0) ||
           BI->getSuccessor(0) == PBI->getSuccessor(1))) {
        for (auto I = BB->instructionsWithoutDebug().begin(),
                  E = BB->instructionsWithoutDebug().end();
             I != E;) {
          Instruction *Curr = &*I++;
          if (isa<CmpInst>(Curr)) {
            Cond = Curr;
            break;
          }
          // Quit if we can't remove this instruction.
          if (!tryCSEWithPredecessor(Curr, PB))
            return Changed;
          Changed = true;
        }
      }

  if (!Cond)
    return Changed;
}

if (!Cond8.1
'Cond' is non-null
1
'Cond' is non-null
1
'Cond' is non-null
1
'Cond' is non-null
1
'Cond' is non-null
1
'Cond' is non-null
 || (!isa<CmpInst>(Cond) && !isa<BinaryOperator>(Cond)) ||
9
←
Assuming 'Cond' is not a 'CmpInst'→
10
←
Assuming 'Cond' is a 'BinaryOperator'→
20
←
Taking false branch→
    Cond->getParent() != BB || !Cond->hasOneUse())
11
←
Assuming the condition is false→
12
←
Calling 'Value::hasOneUse'→
18
←
Returning from 'Value::hasOneUse'→
19
←
Assuming the condition is false→
  return Changed;

// Only allow this transformation if computing the condition doesn't involve
// too many instructions and these involved instructions can be executed
// unconditionally. We denote all involved instructions except the condition
// as "bonus instructions", and only allow this transformation when the
// number of the bonus instructions we'll need to create when cloning into
// each predecessor does not exceed a certain threshold.
unsigned NumBonusInsts = 0;
for (Instruction &I : *BB) {
  // Don't check the branch condition comparison itself.
  if (&I == Cond)
    continue;
  // Ignore dbg intrinsics, and the terminator.
  if (isa<DbgInfoIntrinsic>(I) || isa<BranchInst>(I))
    continue;
  // I must be safe to execute unconditionally.
  if (!isSafeToSpeculativelyExecute(&I))
    return Changed;

  // Account for the cost of duplicating this instruction into each
  // predecessor.
  NumBonusInsts += PredCount;
  // Early exits once we reach the limit.
  if (NumBonusInsts > BonusInstThreshold)
    return Changed;
}

// Also, for now, all liveout uses of bonus instructions must be in PHI nodes
// in successor blocks as incoming values from the bonus instructions's block,
// otherwise we'll fail to update them.
// FIXME: We could lift this restriction, but we need to form PHI nodes and
// rewrite offending uses, but we can't do that without having a domtree.
if (any_of(*BB, [BB](Instruction &I) {
21
←
Calling 'any_of<llvm::BasicBlock &, (lambda at /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp:2915:19)>'→
32
←
Returning from 'any_of<llvm::BasicBlock &, (lambda at /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp:2915:19)>'→
33
←
Taking false branch→
      return any_of(I.uses(), [BB](Use &U) {
        auto *User = cast<Instruction>(U.getUser());
        if (User->getParent() == BB)
          return false; // Not an external use.
        auto *PN = dyn_cast<PHINode>(User);
        return !PN || PN->getIncomingBlock(U) != BB;
      });
    }))
  return Changed;

// Cond is known to be a compare or binary operator.  Check to make sure that
// neither operand is a potentially-trapping constant expression.
if (ConstantExpr *CE34.1
'CE' is null
1
'CE' is null
1
'CE' is null
1
'CE' is null
1
'CE' is null
1
'CE' is null
 = dyn_cast<ConstantExpr>(Cond->getOperand(0)))
34
←
Assuming the object is not a 'ConstantExpr'→
35
←
Taking false branch→
  if (CE->canTrap())
    return Changed;
if (ConstantExpr *CE36.1
'CE' is null
1
'CE' is null
1
'CE' is null
1
'CE' is null
1
'CE' is null
1
'CE' is null
 = dyn_cast<ConstantExpr>(Cond->getOperand(1)))
36
←
Assuming the object is not a 'ConstantExpr'→
37
←
Taking false branch→
  if (CE->canTrap())
    return Changed;

// Finally, don't infinitely unroll conditional loops.
BasicBlock *TrueDest = BI->getSuccessor(0);
BasicBlock *FalseDest = (BI->isConditional()) ? BI->getSuccessor(1) : nullptr;
38
←
'?' condition is true→
if (TrueDest38.1
'TrueDest' is not equal to 'BB'
1
'TrueDest' is not equal to 'BB'
1
'TrueDest' is not equal to 'BB'
1
'TrueDest' is not equal to 'BB'
1
'TrueDest' is not equal to 'BB'
1
'TrueDest' is not equal to 'BB'
 == BB || FalseDest38.2
'FalseDest' is not equal to 'BB'
2
'FalseDest' is not equal to 'BB'
2
'FalseDest' is not equal to 'BB'
2
'FalseDest' is not equal to 'BB'
2
'FalseDest' is not equal to 'BB'
2
'FalseDest' is not equal to 'BB'
 == BB)
39
←
Taking false branch→
  return Changed;

for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
40
←
Loop condition is true.  Entering loop body→
  BasicBlock *PredBlock = *PI;
  BranchInst *PBI = dyn_cast<BranchInst>(PredBlock->getTerminator());
41
←
Assuming the object is a 'BranchInst'→

  // Check that we have two conditional branches.  If there is a PHI node in
  // the common successor, verify that the same value flows in from both
  // blocks.
  SmallVector<PHINode *, 4> PHIs;
  if (!PBI41.1
'PBI' is non-null
1
'PBI' is non-null
1
'PBI' is non-null
1
'PBI' is non-null
1
'PBI' is non-null
1
'PBI' is non-null
 || PBI->isUnconditional() ||
42
←
Calling 'BranchInst::isUnconditional'→
45
←
Returning from 'BranchInst::isUnconditional'→
      (BI->isConditional() && !SafeToMergeTerminators(BI, PBI)) ||
46
←
Calling 'BranchInst::isConditional'→
48
←
Returning from 'BranchInst::isConditional'→
49
←
Calling 'SafeToMergeTerminators'→
53
←
Returning from 'SafeToMergeTerminators'→
      (!BI->isConditional() &&
54
←
Calling 'BranchInst::isConditional'→
56
←
Returning from 'BranchInst::isConditional'→
       !isProfitableToFoldUnconditional(BI, PBI, Cond, PHIs)))
    continue;

  // Determine if the two branches share a common destination.
  Instruction::BinaryOps Opc = Instruction::BinaryOpsEnd;
  bool InvertPredCond = false;

  if (BI->isConditional()) {
57
←
Calling 'BranchInst::isConditional'→
59
←
Returning from 'BranchInst::isConditional'→
60
←
Taking true branch→
    if (PBI->getSuccessor(0) == TrueDest) {
61
←
Taking true branch→
      Opc = Instruction::Or;
    } else if (PBI->getSuccessor(1) == FalseDest) {
      Opc = Instruction::And;
    } else if (PBI->getSuccessor(0) == FalseDest) {
      Opc = Instruction::And;
      InvertPredCond = true;
    } else if (PBI->getSuccessor(1) == TrueDest) {
      Opc = Instruction::Or;
      InvertPredCond = true;
    } else {
      continue;
    }
  } else {
    if (PBI->getSuccessor(0) != TrueDest && PBI->getSuccessor(1) != TrueDest)
      continue;
  }

  // Check the cost of inserting the necessary logic before performing the
  // transformation.
  if (TTI && Opc != Instruction::BinaryOpsEnd) {
62
←
Assuming 'TTI' is null→
    Type *Ty = BI->getCondition()->getType();
    unsigned Cost = TTI->getArithmeticInstrCost(Opc, Ty, CostKind);
    if (InvertPredCond && (!PBI->getCondition()->hasOneUse() ||
        !isa<CmpInst>(PBI->getCondition())))
      Cost += TTI->getArithmeticInstrCost(Instruction::Xor, Ty, CostKind);

    if (Cost > BranchFoldThreshold)
      continue;
  }

  LLVM_DEBUG(dbgs() << "FOLDING BRANCH TO COMMON DEST:\n" << *PBI << *BB)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOLDING BRANCH TO COMMON DEST:\n"
 << *PBI << *BB; } } while (false);
63
←
Assuming 'DebugFlag' is false→
64
←
Loop condition is false.  Exiting loop→
  Changed = true;

  SmallVector<DominatorTree::UpdateType, 3> Updates;

  IRBuilder<> Builder(PBI);
  // The builder is used to create instructions to eliminate the branch in BB.
  // If BB's terminator has !annotation metadata, add it to the new
  // instructions.
  Builder.CollectMetadataToCopy(BB->getTerminator(),
                                {LLVMContext::MD_annotation});

  // If we need to invert the condition in the pred block to match, do so now.
  if (InvertPredCond64.1
'InvertPredCond' is false
1
'InvertPredCond' is false
1
'InvertPredCond' is false
1
'InvertPredCond' is false
1
'InvertPredCond' is false
1
'InvertPredCond' is false
) {
65
←
Taking false branch→
    Value *NewCond = PBI->getCondition();
    if (NewCond->hasOneUse() && isa<CmpInst>(NewCond)) {
      CmpInst *CI = cast<CmpInst>(NewCond);
      CI->setPredicate(CI->getInversePredicate());
    } else {
      NewCond =
          Builder.CreateNot(NewCond, PBI->getCondition()->getName() + ".not");
    }

    PBI->setCondition(NewCond);
    PBI->swapSuccessors();
  }

  BasicBlock *UniqueSucc =
      BI->isConditional()
66
←
'?' condition is true→
          ? (PBI->getSuccessor(0) == BB ? TrueDest : FalseDest)
67
←
'?' condition is false→
          : TrueDest;

  // Before cloning instructions, notify the successor basic block that it
  // is about to have a new predecessor. This will update PHI nodes,
  // which will allow us to update live-out uses of bonus instructions.
  if (BI->isConditional())
68
←
Taking true branch→
    AddPredecessorToBlock(UniqueSucc, PredBlock, BB, MSSAU);

  // If we have bonus instructions, clone them into the predecessor block.
  // Note that there may be multiple predecessor blocks, so we cannot move
  // bonus instructions to a predecessor block.
  ValueToValueMapTy VMap; // maps original values to cloned values
  Instruction *CondInPred;
69
←
'CondInPred' declared without an initial value→
  for (Instruction &BonusInst : *BB) {
    if (isa<DbgInfoIntrinsic>(BonusInst) || isa<BranchInst>(BonusInst))
      continue;

    Instruction *NewBonusInst = BonusInst.clone();

    if (&BonusInst == Cond)
      CondInPred = NewBonusInst;

    if (PBI->getDebugLoc() != NewBonusInst->getDebugLoc()) {
      // Unless the instruction has the same !dbg location as the original
      // branch, drop it. When we fold the bonus instructions we want to make
      // sure we reset their debug locations in order to avoid stepping on
      // dead code caused by folding dead branches.
      NewBonusInst->setDebugLoc(DebugLoc());
    }

    RemapInstruction(NewBonusInst, VMap,
                     RF_NoModuleLevelChanges | RF_IgnoreMissingLocals);
    VMap[&BonusInst] = NewBonusInst;

    // If we moved a load, we cannot any longer claim any knowledge about
    // its potential value. The previous information might have been valid
    // only given the branch precondition.
    // For an analogous reason, we must also drop all the metadata whose
    // semantics we don't understand. We *can* preserve !annotation, because
    // it is tied to the instruction itself, not the value or position.
    NewBonusInst->dropUnknownNonDebugMetadata(LLVMContext::MD_annotation);

    PredBlock->getInstList().insert(PBI->getIterator(), NewBonusInst);
    NewBonusInst->takeName(&BonusInst);
    BonusInst.setName(BonusInst.getName() + ".old");
    BonusInst.replaceUsesWithIf(
        NewBonusInst, [BB, BI, UniqueSucc, PredBlock](Use &U) {
          auto *User = cast<Instruction>(U.getUser());
          // Ignore non-external uses of bonus instructions.
          if (User->getParent() == BB) {
            assert(!isa<PHINode>(User) &&((!isa<PHINode>(User) && "Non-external users are never PHI instructions."
) ? static_cast<void> (0) : __assert_fail ("!isa<PHINode>(User) && \"Non-external users are never PHI instructions.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3072, __PRETTY_FUNCTION__))
                   "Non-external users are never PHI instructions.")((!isa<PHINode>(User) && "Non-external users are never PHI instructions."
) ? static_cast<void> (0) : __assert_fail ("!isa<PHINode>(User) && \"Non-external users are never PHI instructions.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3072, __PRETTY_FUNCTION__));
            return false;
          }
          if (User->getParent() == PredBlock) {
            // The "exteral" use is in the block into which we just cloned the
            // bonus instruction. This means two things: 1. we are in an
            // unreachable block 2. the instruction is self-referencing.
            // So let's just rewrite it...
            return true;
          }
          (void)BI;
          assert(isa<PHINode>(User) && "All external users must be PHI's.")((isa<PHINode>(User) && "All external users must be PHI's."
) ? static_cast<void> (0) : __assert_fail ("isa<PHINode>(User) && \"All external users must be PHI's.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3083, __PRETTY_FUNCTION__));
          auto *PN = cast<PHINode>(User);
          assert(is_contained(successors(BB), User->getParent()) &&((is_contained(successors(BB), User->getParent()) &&
 "All external users must be in successors of BB.") ? static_cast
<void> (0) : __assert_fail ("is_contained(successors(BB), User->getParent()) && \"All external users must be in successors of BB.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3086, __PRETTY_FUNCTION__))
                 "All external users must be in successors of BB.")((is_contained(successors(BB), User->getParent()) &&
 "All external users must be in successors of BB.") ? static_cast
<void> (0) : __assert_fail ("is_contained(successors(BB), User->getParent()) && \"All external users must be in successors of BB.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3086, __PRETTY_FUNCTION__));
          assert((PN->getIncomingBlock(U) == BB ||(((PN->getIncomingBlock(U) == BB || PN->getIncomingBlock
(U) == PredBlock) && "The incoming block for that incoming value external use "
 "must be either the original block with bonus instructions, "
 "or the new predecessor block.") ? static_cast<void> (
0) : __assert_fail ("(PN->getIncomingBlock(U) == BB || PN->getIncomingBlock(U) == PredBlock) && \"The incoming block for that incoming value external use \" \"must be either the original block with bonus instructions, \" \"or the new predecessor block.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3091, __PRETTY_FUNCTION__))
                  PN->getIncomingBlock(U) == PredBlock) &&(((PN->getIncomingBlock(U) == BB || PN->getIncomingBlock
(U) == PredBlock) && "The incoming block for that incoming value external use "
 "must be either the original block with bonus instructions, "
 "or the new predecessor block.") ? static_cast<void> (
0) : __assert_fail ("(PN->getIncomingBlock(U) == BB || PN->getIncomingBlock(U) == PredBlock) && \"The incoming block for that incoming value external use \" \"must be either the original block with bonus instructions, \" \"or the new predecessor block.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3091, __PRETTY_FUNCTION__))
                 "The incoming block for that incoming value external use "(((PN->getIncomingBlock(U) == BB || PN->getIncomingBlock
(U) == PredBlock) && "The incoming block for that incoming value external use "
 "must be either the original block with bonus instructions, "
 "or the new predecessor block.") ? static_cast<void> (
0) : __assert_fail ("(PN->getIncomingBlock(U) == BB || PN->getIncomingBlock(U) == PredBlock) && \"The incoming block for that incoming value external use \" \"must be either the original block with bonus instructions, \" \"or the new predecessor block.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3091, __PRETTY_FUNCTION__))
                 "must be either the original block with bonus instructions, "(((PN->getIncomingBlock(U) == BB || PN->getIncomingBlock
(U) == PredBlock) && "The incoming block for that incoming value external use "
 "must be either the original block with bonus instructions, "
 "or the new predecessor block.") ? static_cast<void> (
0) : __assert_fail ("(PN->getIncomingBlock(U) == BB || PN->getIncomingBlock(U) == PredBlock) && \"The incoming block for that incoming value external use \" \"must be either the original block with bonus instructions, \" \"or the new predecessor block.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3091, __PRETTY_FUNCTION__))
                 "or the new predecessor block.")(((PN->getIncomingBlock(U) == BB || PN->getIncomingBlock
(U) == PredBlock) && "The incoming block for that incoming value external use "
 "must be either the original block with bonus instructions, "
 "or the new predecessor block.") ? static_cast<void> (
0) : __assert_fail ("(PN->getIncomingBlock(U) == BB || PN->getIncomingBlock(U) == PredBlock) && \"The incoming block for that incoming value external use \" \"must be either the original block with bonus instructions, \" \"or the new predecessor block.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3091, __PRETTY_FUNCTION__));
          // UniqueSucc is the block for which we change it's predecessors,
          // so it is the only block in which we'll need to update PHI nodes.
          if (User->getParent() != UniqueSucc)
            return false;
          // Update the incoming value for the new predecessor.
          return PN->getIncomingBlock(U) ==
                 (BI->isConditional() ? PredBlock : BB);
        });
  }

  // Now that the Cond was cloned into the predecessor basic block,
  // or/and the two conditions together.
  if (BI->isConditional()) {
70
←
Calling 'BranchInst::isConditional'→
72
←
Returning from 'BranchInst::isConditional'→
73
←
Taking true branch→
    Instruction *NewCond = cast<Instruction>(
        Builder.CreateBinOp(Opc, PBI->getCondition(), CondInPred, "or.cond"));
74
←
3rd function call argument is an uninitialized value
    PBI->setCondition(NewCond);

    uint64_t PredTrueWeight, PredFalseWeight, SuccTrueWeight, SuccFalseWeight;
    bool HasWeights =
        extractPredSuccWeights(PBI, BI, PredTrueWeight, PredFalseWeight,
                               SuccTrueWeight, SuccFalseWeight);
    SmallVector<uint64_t, 8> NewWeights;

    if (PBI->getSuccessor(0) == BB) {
      if (HasWeights) {
        // PBI: br i1 %x, BB, FalseDest
        // BI:  br i1 %y, UniqueSucc, FalseDest
        // TrueWeight is TrueWeight for PBI * TrueWeight for BI.
        NewWeights.push_back(PredTrueWeight * SuccTrueWeight);
        // FalseWeight is FalseWeight for PBI * TotalWeight for BI +
        //               TrueWeight for PBI * FalseWeight for BI.
        // We assume that total weights of a BranchInst can fit into 32 bits.
        // Therefore, we will not have overflow using 64-bit arithmetic.
        NewWeights.push_back(PredFalseWeight *
                                 (SuccFalseWeight + SuccTrueWeight) +
                             PredTrueWeight * SuccFalseWeight);
      }
      PBI->setSuccessor(0, UniqueSucc);
    }
    if (PBI->getSuccessor(1) == BB) {
      if (HasWeights) {
        // PBI: br i1 %x, TrueDest, BB
        // BI:  br i1 %y, TrueDest, UniqueSucc
        // TrueWeight is TrueWeight for PBI * TotalWeight for BI +
        //              FalseWeight for PBI * TrueWeight for BI.
        NewWeights.push_back(PredTrueWeight *
                                 (SuccFalseWeight + SuccTrueWeight) +
                             PredFalseWeight * SuccTrueWeight);
        // FalseWeight is FalseWeight for PBI * FalseWeight for BI.
        NewWeights.push_back(PredFalseWeight * SuccFalseWeight);
      }
      PBI->setSuccessor(1, UniqueSucc);
    }
    if (NewWeights.size() == 2) {
      // Halve the weights if any of them cannot fit in an uint32_t
      FitWeights(NewWeights);

      SmallVector<uint32_t, 8> MDWeights(NewWeights.begin(),
                                         NewWeights.end());
      setBranchWeights(PBI, MDWeights[0], MDWeights[1]);
    } else
      PBI->setMetadata(LLVMContext::MD_prof, nullptr);

    Updates.push_back({DominatorTree::Insert, PredBlock, UniqueSucc});
    Updates.push_back({DominatorTree::Delete, PredBlock, BB});
  } else {
    // Update PHI nodes in the common successors.
    for (unsigned i = 0, e = PHIs.size(); i != e; ++i) {
      ConstantInt *PBI_C = cast<ConstantInt>(
          PHIs[i]->getIncomingValueForBlock(PBI->getParent()));
      assert(PBI_C->getType()->isIntegerTy(1))((PBI_C->getType()->isIntegerTy(1)) ? static_cast<void
> (0) : __assert_fail ("PBI_C->getType()->isIntegerTy(1)"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3162, __PRETTY_FUNCTION__));
      Instruction *MergedCond = nullptr;
      if (PBI->getSuccessor(0) == UniqueSucc) {
        Updates.push_back(
            {DominatorTree::Delete, PredBlock, PBI->getSuccessor(1)});
        // Create (PBI_Cond and PBI_C) or (!PBI_Cond and BI_Value)
        // PBI_C is true: PBI_Cond or (!PBI_Cond and BI_Value)
        //       is false: !PBI_Cond and BI_Value
        Instruction *NotCond = cast<Instruction>(
            Builder.CreateNot(PBI->getCondition(), "not.cond"));
        MergedCond = cast<Instruction>(
             Builder.CreateBinOp(Instruction::And, NotCond, CondInPred,
                                 "and.cond"));
        if (PBI_C->isOne())
          MergedCond = cast<Instruction>(Builder.CreateBinOp(
              Instruction::Or, PBI->getCondition(), MergedCond, "or.cond"));
      } else {
        assert(PBI->getSuccessor(1) == UniqueSucc && "Unexpected branch")((PBI->getSuccessor(1) == UniqueSucc && "Unexpected branch"
) ? static_cast<void> (0) : __assert_fail ("PBI->getSuccessor(1) == UniqueSucc && \"Unexpected branch\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3179, __PRETTY_FUNCTION__));
        Updates.push_back(
            {DominatorTree::Delete, PredBlock, PBI->getSuccessor(0)});
        // Create (PBI_Cond and BI_Value) or (!PBI_Cond and PBI_C)
        // PBI_C is true: (PBI_Cond and BI_Value) or (!PBI_Cond)
        //       is false: PBI_Cond and BI_Value
        MergedCond = cast<Instruction>(Builder.CreateBinOp(
            Instruction::And, PBI->getCondition(), CondInPred, "and.cond"));
        if (PBI_C->isOne()) {
          Instruction *NotCond = cast<Instruction>(
              Builder.CreateNot(PBI->getCondition(), "not.cond"));
          MergedCond = cast<Instruction>(Builder.CreateBinOp(
              Instruction::Or, NotCond, MergedCond, "or.cond"));
        }
      }
      // Update PHI Node.
      PHIs[i]->setIncomingValueForBlock(PBI->getParent(), MergedCond);
    }

    // PBI is changed to branch to UniqueSucc below. Remove itself from
    // potential phis from all other successors.
    if (MSSAU)
      MSSAU->changeCondBranchToUnconditionalTo(PBI, UniqueSucc);

    // Change PBI from Conditional to Unconditional.
    BranchInst *New_PBI = BranchInst::Create(UniqueSucc, PBI);
    EraseTerminatorAndDCECond(PBI, MSSAU);
    PBI = New_PBI;
  }

  if (DTU)
    DTU->applyUpdates(Updates);

  // If BI was a loop latch, it may have had associated loop metadata.
  // We need to copy it to the new latch, that is, PBI.
  if (MDNode *LoopMD = BI->getMetadata(LLVMContext::MD_loop))
    PBI->setMetadata(LLVMContext::MD_loop, LoopMD);

  // TODO: If BB is reachable from all paths through PredBlock, then we
  // could replace PBI's branch probabilities with BI's.

  // Copy any debug value intrinsics into the end of PredBlock.
  for (Instruction &I : *BB) {
    if (isa<DbgInfoIntrinsic>(I)) {
      Instruction *NewI = I.clone();
      RemapInstruction(NewI, VMap,
                       RF_NoModuleLevelChanges | RF_IgnoreMissingLocals);
      NewI->insertBefore(PBI);
    }
  }

  return Changed;
}
return Changed;
3233}

3235// If there is only one store in BB1 and BB2, return it, otherwise return
3236// nullptr.
3237static StoreInst *findUniqueStoreInBlocks(BasicBlock *BB1, BasicBlock *BB2) {
StoreInst *S = nullptr;
for (auto *BB : {BB1, BB2}) {
  if (!BB)
    continue;
  for (auto &I : *BB)
    if (auto *SI = dyn_cast<StoreInst>(&I)) {
      if (S)
        // Multiple stores seen.
        return nullptr;
      else
        S = SI;
    }
}
return S;
3252}

3254static Value *ensureValueAvailableInSuccessor(Value *V, BasicBlock *BB,
                                            Value *AlternativeV = nullptr) {
// PHI is going to be a PHI node that allows the value V that is defined in
// BB to be referenced in BB's only successor.
//
// If AlternativeV is nullptr, the only value we care about in PHI is V. It
// doesn't matter to us what the other operand is (it'll never get used). We
// could just create a new PHI with an undef incoming value, but that could
// increase register pressure if EarlyCSE/InstCombine can't fold it with some
// other PHI. So here we directly look for some PHI in BB's successor with V
// as an incoming operand. If we find one, we use it, else we create a new
// one.
//
// If AlternativeV is not nullptr, we care about both incoming values in PHI.
// PHI must be exactly: phi <ty> [ %BB, %V ], [ %OtherBB, %AlternativeV]
// where OtherBB is the single other predecessor of BB's only successor.
PHINode *PHI = nullptr;
BasicBlock *Succ = BB->getSingleSuccessor();

for (auto I = Succ->begin(); isa<PHINode>(I); ++I)
  if (cast<PHINode>(I)->getIncomingValueForBlock(BB) == V) {
    PHI = cast<PHINode>(I);
    if (!AlternativeV)
      break;

    assert(Succ->hasNPredecessors(2))((Succ->hasNPredecessors(2)) ? static_cast<void> (0)
 : __assert_fail ("Succ->hasNPredecessors(2)", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3279, __PRETTY_FUNCTION__));
    auto PredI = pred_begin(Succ);
    BasicBlock *OtherPredBB = *PredI == BB ? *++PredI : *PredI;
    if (PHI->getIncomingValueForBlock(OtherPredBB) == AlternativeV)
      break;
    PHI = nullptr;
  }
if (PHI)
  return PHI;

// If V is not an instruction defined in BB, just return it.
if (!AlternativeV &&
    (!isa<Instruction>(V) || cast<Instruction>(V)->getParent() != BB))
  return V;

PHI = PHINode::Create(V->getType(), 2, "simplifycfg.merge", &Succ->front());
PHI->addIncoming(V, BB);
for (BasicBlock *PredBB : predecessors(Succ))
  if (PredBB != BB)
    PHI->addIncoming(
        AlternativeV ? AlternativeV : UndefValue::get(V->getType()), PredBB);
return PHI;
3301}

3303static bool mergeConditionalStoreToAddress(
  BasicBlock *PTB, BasicBlock *PFB, BasicBlock *QTB, BasicBlock *QFB,
  BasicBlock *PostBB, Value *Address, bool InvertPCond, bool InvertQCond,
  DomTreeUpdater *DTU, const DataLayout &DL, const TargetTransformInfo &TTI) {
// For every pointer, there must be exactly two stores, one coming from
// PTB or PFB, and the other from QTB or QFB. We don't support more than one
// store (to any address) in PTB,PFB or QTB,QFB.
// FIXME: We could relax this restriction with a bit more work and performance
// testing.
StoreInst *PStore = findUniqueStoreInBlocks(PTB, PFB);
StoreInst *QStore = findUniqueStoreInBlocks(QTB, QFB);
if (!PStore || !QStore)
  return false;

// Now check the stores are compatible.
if (!QStore->isUnordered() || !PStore->isUnordered())
  return false;

// Check that sinking the store won't cause program behavior changes. Sinking
// the store out of the Q blocks won't change any behavior as we're sinking
// from a block to its unconditional successor. But we're moving a store from
// the P blocks down through the middle block (QBI) and past both QFB and QTB.
// So we need to check that there are no aliasing loads or stores in
// QBI, QTB and QFB. We also need to check there are no conflicting memory
// operations between PStore and the end of its parent block.
//
// The ideal way to do this is to query AliasAnalysis, but we don't
// preserve AA currently so that is dangerous. Be super safe and just
// check there are no other memory operations at all.
for (auto &I : *QFB->getSinglePredecessor())
  if (I.mayReadOrWriteMemory())
    return false;
for (auto &I : *QFB)
  if (&I != QStore && I.mayReadOrWriteMemory())
    return false;
if (QTB)
  for (auto &I : *QTB)
    if (&I != QStore && I.mayReadOrWriteMemory())
      return false;
for (auto I = BasicBlock::iterator(PStore), E = PStore->getParent()->end();
     I != E; ++I)
  if (&*I != PStore && I->mayReadOrWriteMemory())
    return false;

// If we're not in aggressive mode, we only optimize if we have some
// confidence that by optimizing we'll allow P and/or Q to be if-converted.
auto IsWorthwhile = [&](BasicBlock *BB, ArrayRef<StoreInst *> FreeStores) {
  if (!BB)
    return true;
  // Heuristic: if the block can be if-converted/phi-folded and the
  // instructions inside are all cheap (arithmetic/GEPs), it's worthwhile to
  // thread this store.
  int BudgetRemaining =
      PHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic;
  for (auto &I : BB->instructionsWithoutDebug()) {
    // Consider terminator instruction to be free.
    if (I.isTerminator())
      continue;
    // If this is one the stores that we want to speculate out of this BB,
    // then don't count it's cost, consider it to be free.
    if (auto *S = dyn_cast<StoreInst>(&I))
      if (llvm::find(FreeStores, S))
        continue;
    // Else, we have a white-list of instructions that we are ak speculating.
    if (!isa<BinaryOperator>(I) && !isa<GetElementPtrInst>(I))
      return false; // Not in white-list - not worthwhile folding.
    // And finally, if this is a non-free instruction that we are okay
    // speculating, ensure that we consider the speculation budget.
    BudgetRemaining -= TTI.getUserCost(&I, TargetTransformInfo::TCK_SizeAndLatency);
    if (BudgetRemaining < 0)
      return false; // Eagerly refuse to fold as soon as we're out of budget.
  }
  assert(BudgetRemaining >= 0 &&((BudgetRemaining >= 0 && "When we run out of budget we will eagerly return from within the "
 "per-instruction loop.") ? static_cast<void> (0) : __assert_fail
 ("BudgetRemaining >= 0 && \"When we run out of budget we will eagerly return from within the \" \"per-instruction loop.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3377, __PRETTY_FUNCTION__))
         "When we run out of budget we will eagerly return from within the "((BudgetRemaining >= 0 && "When we run out of budget we will eagerly return from within the "
 "per-instruction loop.") ? static_cast<void> (0) : __assert_fail
 ("BudgetRemaining >= 0 && \"When we run out of budget we will eagerly return from within the \" \"per-instruction loop.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3377, __PRETTY_FUNCTION__))
         "per-instruction loop.")((BudgetRemaining >= 0 && "When we run out of budget we will eagerly return from within the "
 "per-instruction loop.") ? static_cast<void> (0) : __assert_fail
 ("BudgetRemaining >= 0 && \"When we run out of budget we will eagerly return from within the \" \"per-instruction loop.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3377, __PRETTY_FUNCTION__));
  return true;
};

const std::array<StoreInst *, 2> FreeStores = {PStore, QStore};
if (!MergeCondStoresAggressively &&
    (!IsWorthwhile(PTB, FreeStores) || !IsWorthwhile(PFB, FreeStores) ||
     !IsWorthwhile(QTB, FreeStores) || !IsWorthwhile(QFB, FreeStores)))
  return false;

// If PostBB has more than two predecessors, we need to split it so we can
// sink the store.
if (std::next(pred_begin(PostBB), 2) != pred_end(PostBB)) {
  // We know that QFB's only successor is PostBB. And QFB has a single
  // predecessor. If QTB exists, then its only successor is also PostBB.
  // If QTB does not exist, then QFB's only predecessor has a conditional
  // branch to QFB and PostBB.
  BasicBlock *TruePred = QTB ? QTB : QFB->getSinglePredecessor();
  BasicBlock *NewBB =
      SplitBlockPredecessors(PostBB, {QFB, TruePred}, "condstore.split", DTU);
  if (!NewBB)
    return false;
  PostBB = NewBB;
}

// OK, we're going to sink the stores to PostBB. The store has to be
// conditional though, so first create the predicate.
Value *PCond = cast<BranchInst>(PFB->getSinglePredecessor()->getTerminator())
                   ->getCondition();
Value *QCond = cast<BranchInst>(QFB->getSinglePredecessor()->getTerminator())
                   ->getCondition();

Value *PPHI = ensureValueAvailableInSuccessor(PStore->getValueOperand(),
                                              PStore->getParent());
Value *QPHI = ensureValueAvailableInSuccessor(QStore->getValueOperand(),
                                              QStore->getParent(), PPHI);

IRBuilder<> QB(&*PostBB->getFirstInsertionPt());

Value *PPred = PStore->getParent() == PTB ? PCond : QB.CreateNot(PCond);
Value *QPred = QStore->getParent() == QTB ? QCond : QB.CreateNot(QCond);

if (InvertPCond)
  PPred = QB.CreateNot(PPred);
if (InvertQCond)
  QPred = QB.CreateNot(QPred);
Value *CombinedPred = QB.CreateOr(PPred, QPred);

auto *T = SplitBlockAndInsertIfThen(CombinedPred, &*QB.GetInsertPoint(),
                                    /*Unreachable=*/false,
                                    /*BranchWeights=*/nullptr, DTU);
QB.SetInsertPoint(T);
StoreInst *SI = cast<StoreInst>(QB.CreateStore(QPHI, Address));
AAMDNodes AAMD;
PStore->getAAMetadata(AAMD, /*Merge=*/false);
PStore->getAAMetadata(AAMD, /*Merge=*/true);
SI->setAAMetadata(AAMD);
// Choose the minimum alignment. If we could prove both stores execute, we
// could use biggest one.  In this case, though, we only know that one of the
// stores executes.  And we don't know it's safe to take the alignment from a
// store that doesn't execute.
SI->setAlignment(std::min(PStore->getAlign(), QStore->getAlign()));

QStore->eraseFromParent();
PStore->eraseFromParent();

return true;
3444}

3446static bool mergeConditionalStores(BranchInst *PBI, BranchInst *QBI,
                                 DomTreeUpdater *DTU, const DataLayout &DL,
                                 const TargetTransformInfo &TTI) {
// The intention here is to find diamonds or triangles (see below) where each
// conditional block contains a store to the same address. Both of these
// stores are conditional, so they can't be unconditionally sunk. But it may
// be profitable to speculatively sink the stores into one merged store at the
// end, and predicate the merged store on the union of the two conditions of
// PBI and QBI.
//
// This can reduce the number of stores executed if both of the conditions are
// true, and can allow the blocks to become small enough to be if-converted.
// This optimization will also chain, so that ladders of test-and-set
// sequences can be if-converted away.
//
// We only deal with simple diamonds or triangles:
//
//     PBI       or      PBI        or a combination of the two
//    /   \               | \
//   PTB  PFB             |  PFB
//    \   /               | /
//     QBI                QBI
//    /  \                | \
//   QTB  QFB             |  QFB
//    \  /                | /
//    PostBB            PostBB
//
// We model triangles as a type of diamond with a nullptr "true" block.
// Triangles are canonicalized so that the fallthrough edge is represented by
// a true condition, as in the diagram above.
BasicBlock *PTB = PBI->getSuccessor(0);
BasicBlock *PFB = PBI->getSuccessor(1);
BasicBlock *QTB = QBI->getSuccessor(0);
BasicBlock *QFB = QBI->getSuccessor(1);
BasicBlock *PostBB = QFB->getSingleSuccessor();

// Make sure we have a good guess for PostBB. If QTB's only successor is
// QFB, then QFB is a better PostBB.
if (QTB->getSingleSuccessor() == QFB)
  PostBB = QFB;

// If we couldn't find a good PostBB, stop.
if (!PostBB)
  return false;

bool InvertPCond = false, InvertQCond = false;
// Canonicalize fallthroughs to the true branches.
if (PFB == QBI->getParent()) {
  std::swap(PFB, PTB);
  InvertPCond = true;
}
if (QFB == PostBB) {
  std::swap(QFB, QTB);
  InvertQCond = true;
}

// From this point on we can assume PTB or QTB may be fallthroughs but PFB
// and QFB may not. Model fallthroughs as a nullptr block.
if (PTB == QBI->getParent())
  PTB = nullptr;
if (QTB == PostBB)
  QTB = nullptr;

// Legality bailouts. We must have at least the non-fallthrough blocks and
// the post-dominating block, and the non-fallthroughs must only have one
// predecessor.
auto HasOnePredAndOneSucc = [](BasicBlock *BB, BasicBlock *P, BasicBlock *S) {
  return BB->getSinglePredecessor() == P && BB->getSingleSuccessor() == S;
};
if (!HasOnePredAndOneSucc(PFB, PBI->getParent(), QBI->getParent()) ||
    !HasOnePredAndOneSucc(QFB, QBI->getParent(), PostBB))
  return false;
if ((PTB && !HasOnePredAndOneSucc(PTB, PBI->getParent(), QBI->getParent())) ||
    (QTB && !HasOnePredAndOneSucc(QTB, QBI->getParent(), PostBB)))
  return false;
if (!QBI->getParent()->hasNUses(2))
  return false;

// OK, this is a sequence of two diamonds or triangles.
// Check if there are stores in PTB or PFB that are repeated in QTB or QFB.
SmallPtrSet<Value *, 4> PStoreAddresses, QStoreAddresses;
for (auto *BB : {PTB, PFB}) {
  if (!BB)
    continue;
  for (auto &I : *BB)
    if (StoreInst *SI = dyn_cast<StoreInst>(&I))
      PStoreAddresses.insert(SI->getPointerOperand());
}
for (auto *BB : {QTB, QFB}) {
  if (!BB)
    continue;
  for (auto &I : *BB)
    if (StoreInst *SI = dyn_cast<StoreInst>(&I))
      QStoreAddresses.insert(SI->getPointerOperand());
}

set_intersect(PStoreAddresses, QStoreAddresses);
// set_intersect mutates PStoreAddresses in place. Rename it here to make it
// clear what it contains.
auto &CommonAddresses = PStoreAddresses;

bool Changed = false;
for (auto *Address : CommonAddresses)
  Changed |=
      mergeConditionalStoreToAddress(PTB, PFB, QTB, QFB, PostBB, Address,
                                     InvertPCond, InvertQCond, DTU, DL, TTI);
return Changed;
3553}

3555/// If the previous block ended with a widenable branch, determine if reusing
3556/// the target block is profitable and legal.  This will have the effect of
3557/// "widening" PBI, but doesn't require us to reason about hosting safety.
3558static bool tryWidenCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI,
                                         DomTreeUpdater *DTU) {
// TODO: This can be generalized in two important ways:
// 1) We can allow phi nodes in IfFalseBB and simply reuse all the input
//    values from the PBI edge.
// 2) We can sink side effecting instructions into BI's fallthrough
//    successor provided they doesn't contribute to computation of
//    BI's condition.
Value *CondWB, *WC;
BasicBlock *IfTrueBB, *IfFalseBB;
if (!parseWidenableBranch(PBI, CondWB, WC, IfTrueBB, IfFalseBB) ||
    IfTrueBB != BI->getParent() || !BI->getParent()->getSinglePredecessor())
  return false;
if (!IfFalseBB->phis().empty())
  return false; // TODO
// Use lambda to lazily compute expensive condition after cheap ones.
auto NoSideEffects = [](BasicBlock &BB) {
  return !llvm::any_of(BB, [](const Instruction &I) {
      return I.mayWriteToMemory() || I.mayHaveSideEffects();
    });
};
if (BI->getSuccessor(1) != IfFalseBB && // no inf looping
    BI->getSuccessor(1)->getTerminatingDeoptimizeCall() && // profitability
    NoSideEffects(*BI->getParent())) {
  auto *OldSuccessor = BI->getSuccessor(1);
  OldSuccessor->removePredecessor(BI->getParent());
  BI->setSuccessor(1, IfFalseBB);
  if (DTU)
    DTU->applyUpdates(
        {{DominatorTree::Insert, BI->getParent(), IfFalseBB},
         {DominatorTree::Delete, BI->getParent(), OldSuccessor}});
  return true;
}
if (BI->getSuccessor(0) != IfFalseBB && // no inf looping
    BI->getSuccessor(0)->getTerminatingDeoptimizeCall() && // profitability
    NoSideEffects(*BI->getParent())) {
  auto *OldSuccessor = BI->getSuccessor(0);
  OldSuccessor->removePredecessor(BI->getParent());
  BI->setSuccessor(0, IfFalseBB);
  if (DTU)
    DTU->applyUpdates(
        {{DominatorTree::Insert, BI->getParent(), IfFalseBB},
         {DominatorTree::Delete, BI->getParent(), OldSuccessor}});
  return true;
}
return false;
3604}

3606/// If we have a conditional branch as a predecessor of another block,
3607/// this function tries to simplify it.  We know
3608/// that PBI and BI are both conditional branches, and BI is in one of the
3609/// successor blocks of PBI - PBI branches to BI.
3610static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI,
                                         DomTreeUpdater *DTU,
                                         const DataLayout &DL,
                                         const TargetTransformInfo &TTI) {
assert(PBI->isConditional() && BI->isConditional())((PBI->isConditional() && BI->isConditional()) ?
 static_cast<void> (0) : __assert_fail ("PBI->isConditional() && BI->isConditional()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 3614, __PRETTY_FUNCTION__));
BasicBlock *BB = BI->getParent();

// If this block ends with a branch instruction, and if there is a
// predecessor that ends on a branch of the same condition, make
// this conditional branch redundant.
if (PBI->getCondition() == BI->getCondition() &&
    PBI->getSuccessor(0) != PBI->getSuccessor(1)) {
  // Okay, the outcome of this conditional branch is statically
  // knowable.  If this block had a single pred, handle specially.
  if (BB->getSinglePredecessor()) {
    // Turn this into a branch on constant.
    bool CondIsTrue = PBI->getSuccessor(0) == BB;
    BI->setCondition(
        ConstantInt::get(Type::getInt1Ty(BB->getContext()), CondIsTrue));
    return true; // Nuke the branch on constant.
  }

  // Otherwise, if there are multiple predecessors, insert a PHI that merges
  // in the constant and simplify the block result.  Subsequent passes of
  // simplifycfg will thread the block.
  if (BlockIsSimpleEnoughToThreadThrough(BB)) {
    pred_iterator PB = pred_begin(BB), PE = pred_end(BB);
    PHINode *NewPN = PHINode::Create(
        Type::getInt1Ty(BB->getContext()), std::distance(PB, PE),
        BI->getCondition()->getName() + ".pr", &BB->front());
    // Okay, we're going to insert the PHI node.  Since PBI is not the only
    // predecessor, compute the PHI'd conditional value for all of the preds.
    // Any predecessor where the condition is not computable we keep symbolic.
    for (pred_iterator PI = PB; PI != PE; ++PI) {
      BasicBlock *P = *PI;
      if ((PBI = dyn_cast<BranchInst>(P->getTerminator())) && PBI != BI &&
          PBI->isConditional() && PBI->getCondition() == BI->getCondition() &&
          PBI->getSuccessor(0) != PBI->getSuccessor(1)) {
        bool CondIsTrue = PBI->getSuccessor(0) == BB;
        NewPN->addIncoming(
            ConstantInt::get(Type::getInt1Ty(BB->getContext()), CondIsTrue),
            P);
      } else {
        NewPN->addIncoming(BI->getCondition(), P);
      }
    }

    BI->setCondition(NewPN);
    return true;
  }
}

// If the previous block ended with a widenable branch, determine if reusing
// the target block is profitable and legal.  This will have the effect of
// "widening" PBI, but doesn't require us to reason about hosting safety.
if (tryWidenCondBranchToCondBranch(PBI, BI, DTU))
  return true;

if (auto *CE = dyn_cast<ConstantExpr>(BI->getCondition()))
  if (CE->canTrap())
    return false;

// If both branches are conditional and both contain stores to the same
// address, remove the stores from the conditionals and create a conditional
// merged store at the end.
if (MergeCondStores && mergeConditionalStores(PBI, BI, DTU, DL, TTI))
  return true;

// If this is a conditional branch in an empty block, and if any
// predecessors are a conditional branch to one of our destinations,
// fold the conditions into logical ops and one cond br.

// Ignore dbg intrinsics.
if (&*BB->instructionsWithoutDebug().begin() != BI)
  return false;

int PBIOp, BIOp;
if (PBI->getSuccessor(0) == BI->getSuccessor(0)) {
  PBIOp = 0;
  BIOp = 0;
} else if (PBI->getSuccessor(0) == BI->getSuccessor(1)) {
  PBIOp = 0;
  BIOp = 1;
} else if (PBI->getSuccessor(1) == BI->getSuccessor(0)) {
  PBIOp = 1;
  BIOp = 0;
} else if (PBI->getSuccessor(1) == BI->getSuccessor(1)) {
  PBIOp = 1;
  BIOp = 1;
} else {
  return false;
}

// Check to make sure that the other destination of this branch
// isn't BB itself.  If so, this is an infinite loop that will
// keep getting unwound.
if (PBI->getSuccessor(PBIOp) == BB)
  return false;

// Do not perform this transformation if it would require
// insertion of a large number of select instructions. For targets
// without predication/cmovs, this is a big pessimization.

// Also do not perform this transformation if any phi node in the common
// destination block can trap when reached by BB or PBB (PR17073). In that
// case, it would be unsafe to hoist the operation into a select instruction.

BasicBlock *CommonDest = PBI->getSuccessor(PBIOp);
BasicBlock *RemovedDest = PBI->getSuccessor(PBIOp ^ 1);
unsigned NumPhis = 0;
for (BasicBlock::iterator II = CommonDest->begin(); isa<PHINode>(II);
     ++II, ++NumPhis) {
  if (NumPhis > 2) // Disable this xform.
    return false;

  PHINode *PN = cast<PHINode>(II);
  Value *BIV = PN->getIncomingValueForBlock(BB);
  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(BIV))
    if (CE->canTrap())
      return false;

  unsigned PBBIdx = PN->getBasicBlockIndex(PBI->getParent());
  Value *PBIV = PN->getIncomingValue(PBBIdx);
  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(PBIV))
    if (CE->canTrap())
      return false;
}

// Finally, if everything is ok, fold the branches to logical ops.
BasicBlock *OtherDest = BI->getSuccessor(BIOp ^ 1);

LLVM_DEBUG(dbgs() << "FOLDING BRs:" << *PBI->getParent()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOLDING BRs:" << *PBI
->getParent() << "AND: " << *BI->getParent(
); } } while (false)
                  << "AND: " << *BI->getParent())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOLDING BRs:" << *PBI
->getParent() << "AND: " << *BI->getParent(
); } } while (false);

SmallVector<DominatorTree::UpdateType, 5> Updates;

// If OtherDest *is* BB, then BB is a basic block with a single conditional
// branch in it, where one edge (OtherDest) goes back to itself but the other
// exits.  We don't *know* that the program avoids the infinite loop
// (even though that seems likely).  If we do this xform naively, we'll end up
// recursively unpeeling the loop.  Since we know that (after the xform is
// done) that the block *is* infinite if reached, we just make it an obviously
// infinite loop with no cond branch.
if (OtherDest == BB) {
  // Insert it at the end of the function, because it's either code,
  // or it won't matter if it's hot. :)
  BasicBlock *InfLoopBlock =
      BasicBlock::Create(BB->getContext(), "infloop", BB->getParent());
  BranchInst::Create(InfLoopBlock, InfLoopBlock);
  Updates.push_back({DominatorTree::Insert, InfLoopBlock, InfLoopBlock});
  OtherDest = InfLoopBlock;
}

LLVM_DEBUG(dbgs() << *PBI->getParent()->getParent())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << *PBI->getParent()->getParent
(); } } while (false);

// BI may have other predecessors.  Because of this, we leave
// it alone, but modify PBI.

// Make sure we get to CommonDest on True&True directions.
Value *PBICond = PBI->getCondition();
IRBuilder<NoFolder> Builder(PBI);
if (PBIOp)
  PBICond = Builder.CreateNot(PBICond, PBICond->getName() + ".not");

Value *BICond = BI->getCondition();
if (BIOp)
  BICond = Builder.CreateNot(BICond, BICond->getName() + ".not");

// Merge the conditions.
Value *Cond = Builder.CreateOr(PBICond, BICond, "brmerge");

// Modify PBI to branch on the new condition to the new dests.
PBI->setCondition(Cond);
PBI->setSuccessor(0, CommonDest);
PBI->setSuccessor(1, OtherDest);

Updates.push_back({DominatorTree::Insert, PBI->getParent(), OtherDest});
Updates.push_back({DominatorTree::Delete, PBI->getParent(), RemovedDest});

if (DTU)
  DTU->applyUpdates(Updates);

// Update branch weight for PBI.
uint64_t PredTrueWeight, PredFalseWeight, SuccTrueWeight, SuccFalseWeight;
uint64_t PredCommon, PredOther, SuccCommon, SuccOther;
bool HasWeights =
    extractPredSuccWeights(PBI, BI, PredTrueWeight, PredFalseWeight,
                           SuccTrueWeight, SuccFalseWeight);
if (HasWeights) {
  PredCommon = PBIOp ? PredFalseWeight : PredTrueWeight;
  PredOther = PBIOp ? PredTrueWeight : PredFalseWeight;
  SuccCommon = BIOp ? SuccFalseWeight : SuccTrueWeight;
  SuccOther = BIOp ? SuccTrueWeight : SuccFalseWeight;
  // The weight to CommonDest should be PredCommon * SuccTotal +
  //                                    PredOther * SuccCommon.
  // The weight to OtherDest should be PredOther * SuccOther.
  uint64_t NewWeights[2] = {PredCommon * (SuccCommon + SuccOther) +
                                PredOther * SuccCommon,
                            PredOther * SuccOther};
  // Halve the weights if any of them cannot fit in an uint32_t
  FitWeights(NewWeights);

  setBranchWeights(PBI, NewWeights[0], NewWeights[1]);
}

// OtherDest may have phi nodes.  If so, add an entry from PBI's
// block that are identical to the entries for BI's block.
AddPredecessorToBlock(OtherDest, PBI->getParent(), BB);

// We know that the CommonDest already had an edge from PBI to
// it.  If it has PHIs though, the PHIs may have different
// entries for BB and PBI's BB.  If so, insert a select to make
// them agree.
for (PHINode &PN : CommonDest->phis()) {
  Value *BIV = PN.getIncomingValueForBlock(BB);
  unsigned PBBIdx = PN.getBasicBlockIndex(PBI->getParent());
  Value *PBIV = PN.getIncomingValue(PBBIdx);
  if (BIV != PBIV) {
    // Insert a select in PBI to pick the right value.
    SelectInst *NV = cast<SelectInst>(
        Builder.CreateSelect(PBICond, PBIV, BIV, PBIV->getName() + ".mux"));
    PN.setIncomingValue(PBBIdx, NV);
    // Although the select has the same condition as PBI, the original branch
    // weights for PBI do not apply to the new select because the select's
    // 'logical' edges are incoming edges of the phi that is eliminated, not
    // the outgoing edges of PBI.
    if (HasWeights) {
      uint64_t PredCommon = PBIOp ? PredFalseWeight : PredTrueWeight;
      uint64_t PredOther = PBIOp ? PredTrueWeight : PredFalseWeight;
      uint64_t SuccCommon = BIOp ? SuccFalseWeight : SuccTrueWeight;
      uint64_t SuccOther = BIOp ? SuccTrueWeight : SuccFalseWeight;
      // The weight to PredCommonDest should be PredCommon * SuccTotal.
      // The weight to PredOtherDest should be PredOther * SuccCommon.
      uint64_t NewWeights[2] = {PredCommon * (SuccCommon + SuccOther),
                                PredOther * SuccCommon};

      FitWeights(NewWeights);

      setBranchWeights(NV, NewWeights[0], NewWeights[1]);
    }
  }
}

LLVM_DEBUG(dbgs() << "INTO: " << *PBI->getParent())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "INTO: " << *PBI->
getParent(); } } while (false);
LLVM_DEBUG(dbgs() << *PBI->getParent()->getParent())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << *PBI->getParent()->getParent
(); } } while (false);

// This basic block is probably dead.  We know it has at least
// one fewer predecessor.
return true;
3859}

3861// Simplifies a terminator by replacing it with a branch to TrueBB if Cond is
3862// true or to FalseBB if Cond is false.
3863// Takes care of updating the successors and removing the old terminator.
3864// Also makes sure not to introduce new successors by assuming that edges to
3865// non-successor TrueBBs and FalseBBs aren't reachable.
3866bool SimplifyCFGOpt::SimplifyTerminatorOnSelect(Instruction *OldTerm,
                                              Value *Cond, BasicBlock *TrueBB,
                                              BasicBlock *FalseBB,
                                              uint32_t TrueWeight,
                                              uint32_t FalseWeight) {
auto *BB = OldTerm->getParent();
// Remove any superfluous successor edges from the CFG.
// First, figure out which successors to preserve.
// If TrueBB and FalseBB are equal, only try to preserve one copy of that
// successor.
BasicBlock *KeepEdge1 = TrueBB;
BasicBlock *KeepEdge2 = TrueBB != FalseBB ? FalseBB : nullptr;

SmallSetVector<BasicBlock *, 2> RemovedSuccessors;

// Then remove the rest.
for (BasicBlock *Succ : successors(OldTerm)) {
  // Make sure only to keep exactly one copy of each edge.
  if (Succ == KeepEdge1)
    KeepEdge1 = nullptr;
  else if (Succ == KeepEdge2)
    KeepEdge2 = nullptr;
  else {
    Succ->removePredecessor(BB,
                            /*KeepOneInputPHIs=*/true);

    if (Succ != TrueBB && Succ != FalseBB)
      RemovedSuccessors.insert(Succ);
  }
}

IRBuilder<> Builder(OldTerm);
Builder.SetCurrentDebugLocation(OldTerm->getDebugLoc());

// Insert an appropriate new terminator.
if (!KeepEdge1 && !KeepEdge2) {
  if (TrueBB == FalseBB) {
    // We were only looking for one successor, and it was present.
    // Create an unconditional branch to it.
    Builder.CreateBr(TrueBB);
  } else {
    // We found both of the successors we were looking for.
    // Create a conditional branch sharing the condition of the select.
    BranchInst *NewBI = Builder.CreateCondBr(Cond, TrueBB, FalseBB);
    if (TrueWeight != FalseWeight)
      setBranchWeights(NewBI, TrueWeight, FalseWeight);
  }
} else if (KeepEdge1 && (KeepEdge2 || TrueBB == FalseBB)) {
  // Neither of the selected blocks were successors, so this
  // terminator must be unreachable.
  new UnreachableInst(OldTerm->getContext(), OldTerm);
} else {
  // One of the selected values was a successor, but the other wasn't.
  // Insert an unconditional branch to the one that was found;
  // the edge to the one that wasn't must be unreachable.
  if (!KeepEdge1) {
    // Only TrueBB was found.
    Builder.CreateBr(TrueBB);
  } else {
    // Only FalseBB was found.
    Builder.CreateBr(FalseBB);
  }
}

EraseTerminatorAndDCECond(OldTerm);

if (DTU) {
  SmallVector<DominatorTree::UpdateType, 2> Updates;
  Updates.reserve(RemovedSuccessors.size());
  for (auto *RemovedSuccessor : RemovedSuccessors)
    Updates.push_back({DominatorTree::Delete, BB, RemovedSuccessor});
  DTU->applyUpdates(Updates);
}

return true;
3941}

3943// Replaces
3944//   (switch (select cond, X, Y)) on constant X, Y
3945// with a branch - conditional if X and Y lead to distinct BBs,
3946// unconditional otherwise.
3947bool SimplifyCFGOpt::SimplifySwitchOnSelect(SwitchInst *SI,
                                          SelectInst *Select) {
// Check for constant integer values in the select.
ConstantInt *TrueVal = dyn_cast<ConstantInt>(Select->getTrueValue());
ConstantInt *FalseVal = dyn_cast<ConstantInt>(Select->getFalseValue());
if (!TrueVal || !FalseVal)
  return false;

// Find the relevant condition and destinations.
Value *Condition = Select->getCondition();
BasicBlock *TrueBB = SI->findCaseValue(TrueVal)->getCaseSuccessor();
BasicBlock *FalseBB = SI->findCaseValue(FalseVal)->getCaseSuccessor();

// Get weight for TrueBB and FalseBB.
uint32_t TrueWeight = 0, FalseWeight = 0;
SmallVector<uint64_t, 8> Weights;
bool HasWeights = HasBranchWeights(SI);
if (HasWeights) {
  GetBranchWeights(SI, Weights);
  if (Weights.size() == 1 + SI->getNumCases()) {
    TrueWeight =
        (uint32_t)Weights[SI->findCaseValue(TrueVal)->getSuccessorIndex()];
    FalseWeight =
        (uint32_t)Weights[SI->findCaseValue(FalseVal)->getSuccessorIndex()];
  }
}

// Perform the actual simplification.
return SimplifyTerminatorOnSelect(SI, Condition, TrueBB, FalseBB, TrueWeight,
                                  FalseWeight);
3977}

3979// Replaces
3980//   (indirectbr (select cond, blockaddress(@fn, BlockA),
3981//                             blockaddress(@fn, BlockB)))
3982// with
3983//   (br cond, BlockA, BlockB).
3984bool SimplifyCFGOpt::SimplifyIndirectBrOnSelect(IndirectBrInst *IBI,
                                              SelectInst *SI) {
// Check that both operands of the select are block addresses.
BlockAddress *TBA = dyn_cast<BlockAddress>(SI->getTrueValue());
BlockAddress *FBA = dyn_cast<BlockAddress>(SI->getFalseValue());
if (!TBA || !FBA)
  return false;

// Extract the actual blocks.
BasicBlock *TrueBB = TBA->getBasicBlock();
BasicBlock *FalseBB = FBA->getBasicBlock();

// Perform the actual simplification.
return SimplifyTerminatorOnSelect(IBI, SI->getCondition(), TrueBB, FalseBB, 0,
                                  0);
3999}

4001/// This is called when we find an icmp instruction
4002/// (a seteq/setne with a constant) as the only instruction in a
4003/// block that ends with an uncond branch.  We are looking for a very specific
4004/// pattern that occurs when "A == 1 || A == 2 || A == 3" gets simplified.  In
4005/// this case, we merge the first two "or's of icmp" into a switch, but then the
4006/// default value goes to an uncond block with a seteq in it, we get something
4007/// like:
4008///
4009///   switch i8 %A, label %DEFAULT [ i8 1, label %end    i8 2, label %end ]
4010/// DEFAULT:
4011///   %tmp = icmp eq i8 %A, 92
4012///   br label %end
4013/// end:
4014///   ... = phi i1 [ true, %entry ], [ %tmp, %DEFAULT ], [ true, %entry ]
4015///
4016/// We prefer to split the edge to 'end' so that there is a true/false entry to
4017/// the PHI, merging the third icmp into the switch.
4018bool SimplifyCFGOpt::tryToSimplifyUncondBranchWithICmpInIt(
  ICmpInst *ICI, IRBuilder<> &Builder) {
BasicBlock *BB = ICI->getParent();

// If the block has any PHIs in it or the icmp has multiple uses, it is too
// complex.
if (isa<PHINode>(BB->begin()) || !ICI->hasOneUse())
  return false;

Value *V = ICI->getOperand(0);
ConstantInt *Cst = cast<ConstantInt>(ICI->getOperand(1));

// The pattern we're looking for is where our only predecessor is a switch on
// 'V' and this block is the default case for the switch.  In this case we can
// fold the compared value into the switch to simplify things.
BasicBlock *Pred = BB->getSinglePredecessor();
if (!Pred || !isa<SwitchInst>(Pred->getTerminator()))
  return false;

SwitchInst *SI = cast<SwitchInst>(Pred->getTerminator());
if (SI->getCondition() != V)
  return false;

// If BB is reachable on a non-default case, then we simply know the value of
// V in this block.  Substitute it and constant fold the icmp instruction
// away.
if (SI->getDefaultDest() != BB) {
  ConstantInt *VVal = SI->findCaseDest(BB);
  assert(VVal && "Should have a unique destination value")((VVal && "Should have a unique destination value") ?
 static_cast<void> (0) : __assert_fail ("VVal && \"Should have a unique destination value\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4046, __PRETTY_FUNCTION__));
  ICI->setOperand(0, VVal);

  if (Value *V = SimplifyInstruction(ICI, {DL, ICI})) {
    ICI->replaceAllUsesWith(V);
    ICI->eraseFromParent();
  }
  // BB is now empty, so it is likely to simplify away.
  return requestResimplify();
}

// Ok, the block is reachable from the default dest.  If the constant we're
// comparing exists in one of the other edges, then we can constant fold ICI
// and zap it.
if (SI->findCaseValue(Cst) != SI->case_default()) {
  Value *V;
  if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
    V = ConstantInt::getFalse(BB->getContext());
  else
    V = ConstantInt::getTrue(BB->getContext());

  ICI->replaceAllUsesWith(V);
  ICI->eraseFromParent();
  // BB is now empty, so it is likely to simplify away.
  return requestResimplify();
}

// The use of the icmp has to be in the 'end' block, by the only PHI node in
// the block.
BasicBlock *SuccBlock = BB->getTerminator()->getSuccessor(0);
PHINode *PHIUse = dyn_cast<PHINode>(ICI->user_back());
if (PHIUse == nullptr || PHIUse != &SuccBlock->front() ||
    isa<PHINode>(++BasicBlock::iterator(PHIUse)))
  return false;

// If the icmp is a SETEQ, then the default dest gets false, the new edge gets
// true in the PHI.
Constant *DefaultCst = ConstantInt::getTrue(BB->getContext());
Constant *NewCst = ConstantInt::getFalse(BB->getContext());

if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
  std::swap(DefaultCst, NewCst);

// Replace ICI (which is used by the PHI for the default value) with true or
// false depending on if it is EQ or NE.
ICI->replaceAllUsesWith(DefaultCst);
ICI->eraseFromParent();

SmallVector<DominatorTree::UpdateType, 2> Updates;

// Okay, the switch goes to this block on a default value.  Add an edge from
// the switch to the merge point on the compared value.
BasicBlock *NewBB =
    BasicBlock::Create(BB->getContext(), "switch.edge", BB->getParent(), BB);
{
  SwitchInstProfUpdateWrapper SIW(*SI);
  auto W0 = SIW.getSuccessorWeight(0);
  SwitchInstProfUpdateWrapper::CaseWeightOpt NewW;
  if (W0) {
    NewW = ((uint64_t(*W0) + 1) >> 1);
    SIW.setSuccessorWeight(0, *NewW);
  }
  SIW.addCase(Cst, NewBB, NewW);
  Updates.push_back({DominatorTree::Insert, Pred, NewBB});
}

// NewBB branches to the phi block, add the uncond branch and the phi entry.
Builder.SetInsertPoint(NewBB);
Builder.SetCurrentDebugLocation(SI->getDebugLoc());
Builder.CreateBr(SuccBlock);
Updates.push_back({DominatorTree::Insert, NewBB, SuccBlock});
PHIUse->addIncoming(NewCst, NewBB);
if (DTU)
  DTU->applyUpdates(Updates);
return true;
4121}

4123/// The specified branch is a conditional branch.
4124/// Check to see if it is branching on an or/and chain of icmp instructions, and
4125/// fold it into a switch instruction if so.
4126bool SimplifyCFGOpt::SimplifyBranchOnICmpChain(BranchInst *BI,
                                             IRBuilder<> &Builder,
                                             const DataLayout &DL) {
Instruction *Cond = dyn_cast<Instruction>(BI->getCondition());
if (!Cond)
  return false;

// Change br (X == 0 | X == 1), T, F into a switch instruction.
// If this is a bunch of seteq's or'd together, or if it's a bunch of
// 'setne's and'ed together, collect them.

// Try to gather values from a chain of and/or to be turned into a switch
ConstantComparesGatherer ConstantCompare(Cond, DL);
// Unpack the result
SmallVectorImpl<ConstantInt *> &Values = ConstantCompare.Vals;
Value *CompVal = ConstantCompare.CompValue;
unsigned UsedICmps = ConstantCompare.UsedICmps;
Value *ExtraCase = ConstantCompare.Extra;

// If we didn't have a multiply compared value, fail.
if (!CompVal)
  return false;

// Avoid turning single icmps into a switch.
if (UsedICmps <= 1)
  return false;

bool TrueWhenEqual = match(Cond, m_LogicalOr(m_Value(), m_Value()));

// There might be duplicate constants in the list, which the switch
// instruction can't handle, remove them now.
array_pod_sort(Values.begin(), Values.end(), ConstantIntSortPredicate);
Values.erase(std::unique(Values.begin(), Values.end()), Values.end());

// If Extra was used, we require at least two switch values to do the
// transformation.  A switch with one value is just a conditional branch.
if (ExtraCase && Values.size() < 2)
  return false;

// TODO: Preserve branch weight metadata, similarly to how
// FoldValueComparisonIntoPredecessors preserves it.

// Figure out which block is which destination.
BasicBlock *DefaultBB = BI->getSuccessor(1);
BasicBlock *EdgeBB = BI->getSuccessor(0);
if (!TrueWhenEqual)
  std::swap(DefaultBB, EdgeBB);

BasicBlock *BB = BI->getParent();

// MSAN does not like undefs as branch condition which can be introduced
// with "explicit branch".
if (ExtraCase && BB->getParent()->hasFnAttribute(Attribute::SanitizeMemory))
  return false;

LLVM_DEBUG(dbgs() << "Converting 'icmp' chain with " << Values.size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Converting 'icmp' chain with "
 << Values.size() << " cases into SWITCH.  BB is:\n"
 << *BB; } } while (false)
                  << " cases into SWITCH.  BB is:\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Converting 'icmp' chain with "
 << Values.size() << " cases into SWITCH.  BB is:\n"
 << *BB; } } while (false)
                  << *BB)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Converting 'icmp' chain with "
 << Values.size() << " cases into SWITCH.  BB is:\n"
 << *BB; } } while (false);

SmallVector<DominatorTree::UpdateType, 2> Updates;

// If there are any extra values that couldn't be folded into the switch
// then we evaluate them with an explicit branch first. Split the block
// right before the condbr to handle it.
if (ExtraCase) {
  BasicBlock *NewBB = SplitBlock(BB, BI, DTU, /*LI=*/nullptr,
                                 /*MSSAU=*/nullptr, "switch.early.test");

  // Remove the uncond branch added to the old block.
  Instruction *OldTI = BB->getTerminator();
  Builder.SetInsertPoint(OldTI);

  if (TrueWhenEqual)
    Builder.CreateCondBr(ExtraCase, EdgeBB, NewBB);
  else
    Builder.CreateCondBr(ExtraCase, NewBB, EdgeBB);

  OldTI->eraseFromParent();

  Updates.push_back({DominatorTree::Insert, BB, EdgeBB});

  // If there are PHI nodes in EdgeBB, then we need to add a new entry to them
  // for the edge we just added.
  AddPredecessorToBlock(EdgeBB, BB, NewBB);

  LLVM_DEBUG(dbgs() << "  ** 'icmp' chain unhandled condition: " << *ExtraCasedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "  ** 'icmp' chain unhandled condition: "
 << *ExtraCase << "\nEXTRABB = " << *BB; } }
 while (false)
                    << "\nEXTRABB = " << *BB)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "  ** 'icmp' chain unhandled condition: "
 << *ExtraCase << "\nEXTRABB = " << *BB; } }
 while (false);
  BB = NewBB;
}

Builder.SetInsertPoint(BI);
// Convert pointer to int before we switch.
if (CompVal->getType()->isPointerTy()) {
  CompVal = Builder.CreatePtrToInt(
      CompVal, DL.getIntPtrType(CompVal->getType()), "magicptr");
}

// Create the new switch instruction now.
SwitchInst *New = Builder.CreateSwitch(CompVal, DefaultBB, Values.size());

// Add all of the 'cases' to the switch instruction.
for (unsigned i = 0, e = Values.size(); i != e; ++i)
  New->addCase(Values[i], EdgeBB);

// We added edges from PI to the EdgeBB.  As such, if there were any
// PHI nodes in EdgeBB, they need entries to be added corresponding to
// the number of edges added.
for (BasicBlock::iterator BBI = EdgeBB->begin(); isa<PHINode>(BBI); ++BBI) {
  PHINode *PN = cast<PHINode>(BBI);
  Value *InVal = PN->getIncomingValueForBlock(BB);
  for (unsigned i = 0, e = Values.size() - 1; i != e; ++i)
    PN->addIncoming(InVal, BB);
}

// Erase the old branch instruction.
EraseTerminatorAndDCECond(BI);
if (DTU)
  DTU->applyUpdates(Updates);

LLVM_DEBUG(dbgs() << "  ** 'icmp' chain result is:\n" << *BB << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "  ** 'icmp' chain result is:\n"
 << *BB << '\n'; } } while (false);
return true;
4247}

4249bool SimplifyCFGOpt::simplifyResume(ResumeInst *RI, IRBuilder<> &Builder) {
if (isa<PHINode>(RI->getValue()))
  return simplifyCommonResume(RI);
else if (isa<LandingPadInst>(RI->getParent()->getFirstNonPHI()) &&
         RI->getValue() == RI->getParent()->getFirstNonPHI())
  // The resume must unwind the exception that caused control to branch here.
  return simplifySingleResume(RI);

return false;
4258}

4260// Check if cleanup block is empty
4261static bool isCleanupBlockEmpty(iterator_range<BasicBlock::iterator> R) {
for (Instruction &I : R) {
  auto *II = dyn_cast<IntrinsicInst>(&I);
  if (!II)
    return false;

  Intrinsic::ID IntrinsicID = II->getIntrinsicID();
  switch (IntrinsicID) {
  case Intrinsic::dbg_declare:
  case Intrinsic::dbg_value:
  case Intrinsic::dbg_label:
  case Intrinsic::lifetime_end:
    break;
  default:
    return false;
  }
}
return true;
4279}

4281// Simplify resume that is shared by several landing pads (phi of landing pad).
4282bool SimplifyCFGOpt::simplifyCommonResume(ResumeInst *RI) {
BasicBlock *BB = RI->getParent();

// Check that there are no other instructions except for debug and lifetime
// intrinsics between the phi's and resume instruction.
if (!isCleanupBlockEmpty(
        make_range(RI->getParent()->getFirstNonPHI(), BB->getTerminator())))
  return false;

SmallSetVector<BasicBlock *, 4> TrivialUnwindBlocks;
auto *PhiLPInst = cast<PHINode>(RI->getValue());

// Check incoming blocks to see if any of them are trivial.
for (unsigned Idx = 0, End = PhiLPInst->getNumIncomingValues(); Idx != End;
     Idx++) {
  auto *IncomingBB = PhiLPInst->getIncomingBlock(Idx);
  auto *IncomingValue = PhiLPInst->getIncomingValue(Idx);

  // If the block has other successors, we can not delete it because
  // it has other dependents.
  if (IncomingBB->getUniqueSuccessor() != BB)
    continue;

  auto *LandingPad = dyn_cast<LandingPadInst>(IncomingBB->getFirstNonPHI());
  // Not the landing pad that caused the control to branch here.
  if (IncomingValue != LandingPad)
    continue;

  if (isCleanupBlockEmpty(
          make_range(LandingPad->getNextNode(), IncomingBB->getTerminator())))
    TrivialUnwindBlocks.insert(IncomingBB);
}

// If no trivial unwind blocks, don't do any simplifications.
if (TrivialUnwindBlocks.empty())
  return false;

// Turn all invokes that unwind here into calls.
for (auto *TrivialBB : TrivialUnwindBlocks) {
  // Blocks that will be simplified should be removed from the phi node.
  // Note there could be multiple edges to the resume block, and we need
  // to remove them all.
  while (PhiLPInst->getBasicBlockIndex(TrivialBB) != -1)
    BB->removePredecessor(TrivialBB, true);

  for (pred_iterator PI = pred_begin(TrivialBB), PE = pred_end(TrivialBB);
       PI != PE;) {
    BasicBlock *Pred = *PI++;
    removeUnwindEdge(Pred, DTU);
    ++NumInvokes;
  }

  // In each SimplifyCFG run, only the current processed block can be erased.
  // Otherwise, it will break the iteration of SimplifyCFG pass. So instead
  // of erasing TrivialBB, we only remove the branch to the common resume
  // block so that we can later erase the resume block since it has no
  // predecessors.
  TrivialBB->getTerminator()->eraseFromParent();
  new UnreachableInst(RI->getContext(), TrivialBB);
  if (DTU)
    DTU->applyUpdates({{DominatorTree::Delete, TrivialBB, BB}});
}

// Delete the resume block if all its predecessors have been removed.
if (pred_empty(BB)) {
  if (DTU)
    DTU->deleteBB(BB);
  else
    BB->eraseFromParent();
}

return !TrivialUnwindBlocks.empty();
4354}

4356// Simplify resume that is only used by a single (non-phi) landing pad.
4357bool SimplifyCFGOpt::simplifySingleResume(ResumeInst *RI) {
BasicBlock *BB = RI->getParent();
auto *LPInst = cast<LandingPadInst>(BB->getFirstNonPHI());
assert(RI->getValue() == LPInst &&((RI->getValue() == LPInst && "Resume must unwind the exception that caused control to here"
) ? static_cast<void> (0) : __assert_fail ("RI->getValue() == LPInst && \"Resume must unwind the exception that caused control to here\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4361, __PRETTY_FUNCTION__))
       "Resume must unwind the exception that caused control to here")((RI->getValue() == LPInst && "Resume must unwind the exception that caused control to here"
) ? static_cast<void> (0) : __assert_fail ("RI->getValue() == LPInst && \"Resume must unwind the exception that caused control to here\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4361, __PRETTY_FUNCTION__));

// Check that there are no other instructions except for debug intrinsics.
if (!isCleanupBlockEmpty(
        make_range<Instruction *>(LPInst->getNextNode(), RI)))
  return false;

// Turn all invokes that unwind here into calls and delete the basic block.
for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB); PI != PE;) {
  BasicBlock *Pred = *PI++;
  removeUnwindEdge(Pred, DTU);
  ++NumInvokes;
}

// The landingpad is now unreachable.  Zap it.
if (LoopHeaders)
  LoopHeaders->erase(BB);
if (DTU)
  DTU->deleteBB(BB);
else
  BB->eraseFromParent();
return true;
4383}

4385static bool removeEmptyCleanup(CleanupReturnInst *RI, DomTreeUpdater *DTU) {
// If this is a trivial cleanup pad that executes no instructions, it can be
// eliminated.  If the cleanup pad continues to the caller, any predecessor
// that is an EH pad will be updated to continue to the caller and any
// predecessor that terminates with an invoke instruction will have its invoke
// instruction converted to a call instruction.  If the cleanup pad being
// simplified does not continue to the caller, each predecessor will be
// updated to continue to the unwind destination of the cleanup pad being
// simplified.
BasicBlock *BB = RI->getParent();
CleanupPadInst *CPInst = RI->getCleanupPad();
if (CPInst->getParent() != BB)
  // This isn't an empty cleanup.
  return false;

// We cannot kill the pad if it has multiple uses.  This typically arises
// from unreachable basic blocks.
if (!CPInst->hasOneUse())
  return false;

// Check that there are no other instructions except for benign intrinsics.
if (!isCleanupBlockEmpty(
        make_range<Instruction *>(CPInst->getNextNode(), RI)))
  return false;

// If the cleanup return we are simplifying unwinds to the caller, this will
// set UnwindDest to nullptr.
BasicBlock *UnwindDest = RI->getUnwindDest();
Instruction *DestEHPad = UnwindDest ? UnwindDest->getFirstNonPHI() : nullptr;

// We're about to remove BB from the control flow.  Before we do, sink any
// PHINodes into the unwind destination.  Doing this before changing the
// control flow avoids some potentially slow checks, since we can currently
// be certain that UnwindDest and BB have no common predecessors (since they
// are both EH pads).
if (UnwindDest) {
  // First, go through the PHI nodes in UnwindDest and update any nodes that
  // reference the block we are removing
  for (BasicBlock::iterator I = UnwindDest->begin(),
                            IE = DestEHPad->getIterator();
       I != IE; ++I) {
    PHINode *DestPN = cast<PHINode>(I);

    int Idx = DestPN->getBasicBlockIndex(BB);
    // Since BB unwinds to UnwindDest, it has to be in the PHI node.
    assert(Idx != -1)((Idx != -1) ? static_cast<void> (0) : __assert_fail ("Idx != -1"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4430, __PRETTY_FUNCTION__));
    // This PHI node has an incoming value that corresponds to a control
    // path through the cleanup pad we are removing.  If the incoming
    // value is in the cleanup pad, it must be a PHINode (because we
    // verified above that the block is otherwise empty).  Otherwise, the
    // value is either a constant or a value that dominates the cleanup
    // pad being removed.
    //
    // Because BB and UnwindDest are both EH pads, all of their
    // predecessors must unwind to these blocks, and since no instruction
    // can have multiple unwind destinations, there will be no overlap in
    // incoming blocks between SrcPN and DestPN.
    Value *SrcVal = DestPN->getIncomingValue(Idx);
    PHINode *SrcPN = dyn_cast<PHINode>(SrcVal);

    // Remove the entry for the block we are deleting.
    DestPN->removeIncomingValue(Idx, false);

    if (SrcPN && SrcPN->getParent() == BB) {
      // If the incoming value was a PHI node in the cleanup pad we are
      // removing, we need to merge that PHI node's incoming values into
      // DestPN.
      for (unsigned SrcIdx = 0, SrcE = SrcPN->getNumIncomingValues();
           SrcIdx != SrcE; ++SrcIdx) {
        DestPN->addIncoming(SrcPN->getIncomingValue(SrcIdx),
                            SrcPN->getIncomingBlock(SrcIdx));
      }
    } else {
      // Otherwise, the incoming value came from above BB and
      // so we can just reuse it.  We must associate all of BB's
      // predecessors with this value.
      for (auto *pred : predecessors(BB)) {
        DestPN->addIncoming(SrcVal, pred);
      }
    }
  }

  // Sink any remaining PHI nodes directly into UnwindDest.
  Instruction *InsertPt = DestEHPad;
  for (BasicBlock::iterator I = BB->begin(),
                            IE = BB->getFirstNonPHI()->getIterator();
       I != IE;) {
    // The iterator must be incremented here because the instructions are
    // being moved to another block.
    PHINode *PN = cast<PHINode>(I++);
    if (PN->use_empty() || !PN->isUsedOutsideOfBlock(BB))
      // If the PHI node has no uses or all of its uses are in this basic
      // block (meaning they are debug or lifetime intrinsics), just leave
      // it.  It will be erased when we erase BB below.
      continue;

    // Otherwise, sink this PHI node into UnwindDest.
    // Any predecessors to UnwindDest which are not already represented
    // must be back edges which inherit the value from the path through
    // BB.  In this case, the PHI value must reference itself.
    for (auto *pred : predecessors(UnwindDest))
      if (pred != BB)
        PN->addIncoming(PN, pred);
    PN->moveBefore(InsertPt);
  }
}

std::vector<DominatorTree::UpdateType> Updates;

for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB); PI != PE;) {
  // The iterator must be updated here because we are removing this pred.
  BasicBlock *PredBB = *PI++;
  if (UnwindDest == nullptr) {
    if (DTU)
      DTU->applyUpdates(Updates);
    Updates.clear();
    removeUnwindEdge(PredBB, DTU);
    ++NumInvokes;
  } else {
    Instruction *TI = PredBB->getTerminator();
    TI->replaceUsesOfWith(BB, UnwindDest);
    Updates.push_back({DominatorTree::Insert, PredBB, UnwindDest});
    Updates.push_back({DominatorTree::Delete, PredBB, BB});
  }
}

if (DTU) {
  DTU->applyUpdates(Updates);
  DTU->deleteBB(BB);
} else
  // The cleanup pad is now unreachable.  Zap it.
  BB->eraseFromParent();

return true;
4519}

4521// Try to merge two cleanuppads together.
4522static bool mergeCleanupPad(CleanupReturnInst *RI) {
// Skip any cleanuprets which unwind to caller, there is nothing to merge
// with.
BasicBlock *UnwindDest = RI->getUnwindDest();
if (!UnwindDest)
  return false;

// This cleanupret isn't the only predecessor of this cleanuppad, it wouldn't
// be safe to merge without code duplication.
if (UnwindDest->getSinglePredecessor() != RI->getParent())
  return false;

// Verify that our cleanuppad's unwind destination is another cleanuppad.
auto *SuccessorCleanupPad = dyn_cast<CleanupPadInst>(&UnwindDest->front());
if (!SuccessorCleanupPad)
  return false;

CleanupPadInst *PredecessorCleanupPad = RI->getCleanupPad();
// Replace any uses of the successor cleanupad with the predecessor pad
// The only cleanuppad uses should be this cleanupret, it's cleanupret and
// funclet bundle operands.
SuccessorCleanupPad->replaceAllUsesWith(PredecessorCleanupPad);
// Remove the old cleanuppad.
SuccessorCleanupPad->eraseFromParent();
// Now, we simply replace the cleanupret with a branch to the unwind
// destination.
BranchInst::Create(UnwindDest, RI->getParent());
RI->eraseFromParent();

return true;
4552}

4554bool SimplifyCFGOpt::simplifyCleanupReturn(CleanupReturnInst *RI) {
// It is possible to transiantly have an undef cleanuppad operand because we
// have deleted some, but not all, dead blocks.
// Eventually, this block will be deleted.
if (isa<UndefValue>(RI->getOperand(0)))
  return false;

if (mergeCleanupPad(RI))
  return true;

if (removeEmptyCleanup(RI, DTU))
  return true;

return false;
4568}

4570bool SimplifyCFGOpt::simplifyReturn(ReturnInst *RI, IRBuilder<> &Builder) {
BasicBlock *BB = RI->getParent();
if (!BB->getFirstNonPHIOrDbg()->isTerminator())
  return false;

// Find predecessors that end with branches.
SmallVector<BasicBlock *, 8> UncondBranchPreds;
SmallVector<BranchInst *, 8> CondBranchPreds;
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
  BasicBlock *P = *PI;
  Instruction *PTI = P->getTerminator();
  if (BranchInst *BI = dyn_cast<BranchInst>(PTI)) {
    if (BI->isUnconditional())
      UncondBranchPreds.push_back(P);
    else
      CondBranchPreds.push_back(BI);
  }
}

// If we found some, do the transformation!
if (!UncondBranchPreds.empty() && DupRet) {
  while (!UncondBranchPreds.empty()) {
    BasicBlock *Pred = UncondBranchPreds.pop_back_val();
    LLVM_DEBUG(dbgs() << "FOLDING: " << *BBdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOLDING: " << *BB <<
 "INTO UNCOND BRANCH PRED: " << *Pred; } } while (false
)
                      << "INTO UNCOND BRANCH PRED: " << *Pred)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "FOLDING: " << *BB <<
 "INTO UNCOND BRANCH PRED: " << *Pred; } } while (false
);
    (void)FoldReturnIntoUncondBranch(RI, BB, Pred, DTU);
  }

  // If we eliminated all predecessors of the block, delete the block now.
  if (pred_empty(BB)) {
    // We know there are no successors, so just nuke the block.
    if (LoopHeaders)
      LoopHeaders->erase(BB);
    if (DTU)
      DTU->deleteBB(BB);
    else
      BB->eraseFromParent();
  }

  return true;
}

// Check out all of the conditional branches going to this return
// instruction.  If any of them just select between returns, change the
// branch itself into a select/return pair.
while (!CondBranchPreds.empty()) {
  BranchInst *BI = CondBranchPreds.pop_back_val();

  // Check to see if the non-BB successor is also a return block.
  if (isa<ReturnInst>(BI->getSuccessor(0)->getTerminator()) &&
      isa<ReturnInst>(BI->getSuccessor(1)->getTerminator()) &&
      SimplifyCondBranchToTwoReturns(BI, Builder))
    return true;
}
return false;
4625}

4627bool SimplifyCFGOpt::simplifyUnreachable(UnreachableInst *UI) {
BasicBlock *BB = UI->getParent();

bool Changed = false;

// If there are any instructions immediately before the unreachable that can
// be removed, do so.
while (UI->getIterator() != BB->begin()) {
  BasicBlock::iterator BBI = UI->getIterator();
  --BBI;
  // Do not delete instructions that can have side effects which might cause
  // the unreachable to not be reachable; specifically, calls and volatile
  // operations may have this effect.
  if (isa<CallInst>(BBI) && !isa<DbgInfoIntrinsic>(BBI))
    break;

  if (BBI->mayHaveSideEffects()) {
    if (auto *SI = dyn_cast<StoreInst>(BBI)) {
      if (SI->isVolatile())
        break;
    } else if (auto *LI = dyn_cast<LoadInst>(BBI)) {
      if (LI->isVolatile())
        break;
    } else if (auto *RMWI = dyn_cast<AtomicRMWInst>(BBI)) {
      if (RMWI->isVolatile())
        break;
    } else if (auto *CXI = dyn_cast<AtomicCmpXchgInst>(BBI)) {
      if (CXI->isVolatile())
        break;
    } else if (isa<CatchPadInst>(BBI)) {
      // A catchpad may invoke exception object constructors and such, which
      // in some languages can be arbitrary code, so be conservative by
      // default.
      // For CoreCLR, it just involves a type test, so can be removed.
      if (classifyEHPersonality(BB->getParent()->getPersonalityFn()) !=
          EHPersonality::CoreCLR)
        break;
    } else if (!isa<FenceInst>(BBI) && !isa<VAArgInst>(BBI) &&
               !isa<LandingPadInst>(BBI)) {
      break;
    }
    // Note that deleting LandingPad's here is in fact okay, although it
    // involves a bit of subtle reasoning. If this inst is a LandingPad,
    // all the predecessors of this block will be the unwind edges of Invokes,
    // and we can therefore guarantee this block will be erased.
  }

  // Delete this instruction (any uses are guaranteed to be dead)
  if (!BBI->use_empty())
    BBI->replaceAllUsesWith(UndefValue::get(BBI->getType()));
  BBI->eraseFromParent();
  Changed = true;
}

// If the unreachable instruction is the first in the block, take a gander
// at all of the predecessors of this instruction, and simplify them.
if (&BB->front() != UI)
  return Changed;

std::vector<DominatorTree::UpdateType> Updates;

SmallSetVector<BasicBlock *, 8> Preds(pred_begin(BB), pred_end(BB));
for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
  auto *Predecessor = Preds[i];
  Instruction *TI = Predecessor->getTerminator();
  IRBuilder<> Builder(TI);
  if (auto *BI = dyn_cast<BranchInst>(TI)) {
    // We could either have a proper unconditional branch,
    // or a degenerate conditional branch with matching destinations.
    if (all_of(BI->successors(),
               [BB](auto *Successor) { return Successor == BB; })) {
      new UnreachableInst(TI->getContext(), TI);
      TI->eraseFromParent();
      Changed = true;
    } else {
      assert(BI->isConditional() && "Can't get here with an uncond branch.")((BI->isConditional() && "Can't get here with an uncond branch."
) ? static_cast<void> (0) : __assert_fail ("BI->isConditional() && \"Can't get here with an uncond branch.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4702, __PRETTY_FUNCTION__));
      Value* Cond = BI->getCondition();
      assert(BI->getSuccessor(0) != BI->getSuccessor(1) &&((BI->getSuccessor(0) != BI->getSuccessor(1) &&
 "The destinations are guaranteed to be different here.") ? static_cast
<void> (0) : __assert_fail ("BI->getSuccessor(0) != BI->getSuccessor(1) && \"The destinations are guaranteed to be different here.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4705, __PRETTY_FUNCTION__))
             "The destinations are guaranteed to be different here.")((BI->getSuccessor(0) != BI->getSuccessor(1) &&
 "The destinations are guaranteed to be different here.") ? static_cast
<void> (0) : __assert_fail ("BI->getSuccessor(0) != BI->getSuccessor(1) && \"The destinations are guaranteed to be different here.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4705, __PRETTY_FUNCTION__));
      if (BI->getSuccessor(0) == BB) {
        Builder.CreateAssumption(Builder.CreateNot(Cond));
        Builder.CreateBr(BI->getSuccessor(1));
      } else {
        assert(BI->getSuccessor(1) == BB && "Incorrect CFG")((BI->getSuccessor(1) == BB && "Incorrect CFG") ? static_cast
<void> (0) : __assert_fail ("BI->getSuccessor(1) == BB && \"Incorrect CFG\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4710, __PRETTY_FUNCTION__));
        Builder.CreateAssumption(Cond);
        Builder.CreateBr(BI->getSuccessor(0));
      }
      EraseTerminatorAndDCECond(BI);
      Changed = true;
    }
    Updates.push_back({DominatorTree::Delete, Predecessor, BB});
  } else if (auto *SI = dyn_cast<SwitchInst>(TI)) {
    SwitchInstProfUpdateWrapper SU(*SI);
    for (auto i = SU->case_begin(), e = SU->case_end(); i != e;) {
      if (i->getCaseSuccessor() != BB) {
        ++i;
        continue;
      }
      BB->removePredecessor(SU->getParent());
      i = SU.removeCase(i);
      e = SU->case_end();
      Changed = true;
    }
    // Note that the default destination can't be removed!
    if (SI->getDefaultDest() != BB)
      Updates.push_back({DominatorTree::Delete, Predecessor, BB});
  } else if (auto *II = dyn_cast<InvokeInst>(TI)) {
    if (II->getUnwindDest() == BB) {
      if (DTU)
        DTU->applyUpdates(Updates);
      Updates.clear();
      removeUnwindEdge(TI->getParent(), DTU);
      Changed = true;
    }
  } else if (auto *CSI = dyn_cast<CatchSwitchInst>(TI)) {
    if (CSI->getUnwindDest() == BB) {
      if (DTU)
        DTU->applyUpdates(Updates);
      Updates.clear();
      removeUnwindEdge(TI->getParent(), DTU);
      Changed = true;
      continue;
    }

    for (CatchSwitchInst::handler_iterator I = CSI->handler_begin(),
                                           E = CSI->handler_end();
         I != E; ++I) {
      if (*I == BB) {
        CSI->removeHandler(I);
        --I;
        --E;
        Changed = true;
      }
    }
    Updates.push_back({DominatorTree::Delete, Predecessor, BB});
    if (CSI->getNumHandlers() == 0) {
      if (CSI->hasUnwindDest()) {
        // Redirect all predecessors of the block containing CatchSwitchInst
        // to instead branch to the CatchSwitchInst's unwind destination.
        for (auto *PredecessorOfPredecessor : predecessors(Predecessor)) {
          Updates.push_back({DominatorTree::Insert, PredecessorOfPredecessor,
                             CSI->getUnwindDest()});
          Updates.push_back(
              {DominatorTree::Delete, PredecessorOfPredecessor, Predecessor});
        }
        Predecessor->replaceAllUsesWith(CSI->getUnwindDest());
      } else {
        // Rewrite all preds to unwind to caller (or from invoke to call).
        if (DTU)
          DTU->applyUpdates(Updates);
        Updates.clear();
        SmallVector<BasicBlock *, 8> EHPreds(predecessors(Predecessor));
        for (BasicBlock *EHPred : EHPreds)
          removeUnwindEdge(EHPred, DTU);
      }
      // The catchswitch is no longer reachable.
      new UnreachableInst(CSI->getContext(), CSI);
      CSI->eraseFromParent();
      Changed = true;
    }
  } else if (auto *CRI = dyn_cast<CleanupReturnInst>(TI)) {
    (void)CRI;
    assert(CRI->hasUnwindDest() && CRI->getUnwindDest() == BB &&((CRI->hasUnwindDest() && CRI->getUnwindDest() ==
 BB && "Expected to always have an unwind to BB.") ? static_cast
<void> (0) : __assert_fail ("CRI->hasUnwindDest() && CRI->getUnwindDest() == BB && \"Expected to always have an unwind to BB.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4790, __PRETTY_FUNCTION__))
           "Expected to always have an unwind to BB.")((CRI->hasUnwindDest() && CRI->getUnwindDest() ==
 BB && "Expected to always have an unwind to BB.") ? static_cast
<void> (0) : __assert_fail ("CRI->hasUnwindDest() && CRI->getUnwindDest() == BB && \"Expected to always have an unwind to BB.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4790, __PRETTY_FUNCTION__));
    Updates.push_back({DominatorTree::Delete, Predecessor, BB});
    new UnreachableInst(TI->getContext(), TI);
    TI->eraseFromParent();
    Changed = true;
  }
}

if (DTU)
  DTU->applyUpdates(Updates);

// If this block is now dead, remove it.
if (pred_empty(BB) && BB != &BB->getParent()->getEntryBlock()) {
  // We know there are no successors, so just nuke the block.
  if (LoopHeaders)
    LoopHeaders->erase(BB);
  if (DTU)
    DTU->deleteBB(BB);
  else
    BB->eraseFromParent();
  return true;
}

return Changed;
4814}

4816static bool CasesAreContiguous(SmallVectorImpl<ConstantInt *> &Cases) {
assert(Cases.size() >= 1)((Cases.size() >= 1) ? static_cast<void> (0) : __assert_fail
 ("Cases.size() >= 1", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4817, __PRETTY_FUNCTION__));

array_pod_sort(Cases.begin(), Cases.end(), ConstantIntSortPredicate);
for (size_t I = 1, E = Cases.size(); I != E; ++I) {
  if (Cases[I - 1]->getValue() != Cases[I]->getValue() + 1)
    return false;
}
return true;
4825}

4827static void createUnreachableSwitchDefault(SwitchInst *Switch,
                                         DomTreeUpdater *DTU) {
LLVM_DEBUG(dbgs() << "SimplifyCFG: switch default is dead.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SimplifyCFG: switch default is dead.\n"
; } } while (false);
auto *BB = Switch->getParent();
BasicBlock *NewDefaultBlock = SplitBlockPredecessors(
    Switch->getDefaultDest(), Switch->getParent(), "", DTU);
auto *OrigDefaultBlock = Switch->getDefaultDest();
Switch->setDefaultDest(&*NewDefaultBlock);
if (DTU)
  DTU->applyUpdates({{DominatorTree::Insert, BB, &*NewDefaultBlock},
                     {DominatorTree::Delete, BB, OrigDefaultBlock}});
SplitBlock(&*NewDefaultBlock, &NewDefaultBlock->front(), DTU);
SmallVector<DominatorTree::UpdateType, 2> Updates;
for (auto *Successor : successors(NewDefaultBlock))
  Updates.push_back({DominatorTree::Delete, NewDefaultBlock, Successor});
auto *NewTerminator = NewDefaultBlock->getTerminator();
new UnreachableInst(Switch->getContext(), NewTerminator);
EraseTerminatorAndDCECond(NewTerminator);
if (DTU)
  DTU->applyUpdates(Updates);
4847}

4849/// Turn a switch with two reachable destinations into an integer range
4850/// comparison and branch.
4851bool SimplifyCFGOpt::TurnSwitchRangeIntoICmp(SwitchInst *SI,
                                           IRBuilder<> &Builder) {
assert(SI->getNumCases() > 1 && "Degenerate switch?")((SI->getNumCases() > 1 && "Degenerate switch?"
) ? static_cast<void> (0) : __assert_fail ("SI->getNumCases() > 1 && \"Degenerate switch?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4853, __PRETTY_FUNCTION__));

bool HasDefault =
    !isa<UnreachableInst>(SI->getDefaultDest()->getFirstNonPHIOrDbg());

auto *BB = SI->getParent();

// Partition the cases into two sets with different destinations.
BasicBlock *DestA = HasDefault ? SI->getDefaultDest() : nullptr;
BasicBlock *DestB = nullptr;
SmallVector<ConstantInt *, 16> CasesA;
SmallVector<ConstantInt *, 16> CasesB;

for (auto Case : SI->cases()) {
  BasicBlock *Dest = Case.getCaseSuccessor();
  if (!DestA)
    DestA = Dest;
  if (Dest == DestA) {
    CasesA.push_back(Case.getCaseValue());
    continue;
  }
  if (!DestB)
    DestB = Dest;
  if (Dest == DestB) {
    CasesB.push_back(Case.getCaseValue());
    continue;
  }
  return false; // More than two destinations.
}

assert(DestA && DestB &&((DestA && DestB && "Single-destination switch should have been folded."
) ? static_cast<void> (0) : __assert_fail ("DestA && DestB && \"Single-destination switch should have been folded.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4884, __PRETTY_FUNCTION__))
       "Single-destination switch should have been folded.")((DestA && DestB && "Single-destination switch should have been folded."
) ? static_cast<void> (0) : __assert_fail ("DestA && DestB && \"Single-destination switch should have been folded.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4884, __PRETTY_FUNCTION__));
assert(DestA != DestB)((DestA != DestB) ? static_cast<void> (0) : __assert_fail
 ("DestA != DestB", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4885, __PRETTY_FUNCTION__));
assert(DestB != SI->getDefaultDest())((DestB != SI->getDefaultDest()) ? static_cast<void>
 (0) : __assert_fail ("DestB != SI->getDefaultDest()", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4886, __PRETTY_FUNCTION__));
assert(!CasesB.empty() && "There must be non-default cases.")((!CasesB.empty() && "There must be non-default cases."
) ? static_cast<void> (0) : __assert_fail ("!CasesB.empty() && \"There must be non-default cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4887, __PRETTY_FUNCTION__));
assert(!CasesA.empty() || HasDefault)((!CasesA.empty() || HasDefault) ? static_cast<void> (0
) : __assert_fail ("!CasesA.empty() || HasDefault", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 4888, __PRETTY_FUNCTION__));

// Figure out if one of the sets of cases form a contiguous range.
SmallVectorImpl<ConstantInt *> *ContiguousCases = nullptr;
BasicBlock *ContiguousDest = nullptr;
BasicBlock *OtherDest = nullptr;
if (!CasesA.empty() && CasesAreContiguous(CasesA)) {
  ContiguousCases = &CasesA;
  ContiguousDest = DestA;
  OtherDest = DestB;
} else if (CasesAreContiguous(CasesB)) {
  ContiguousCases = &CasesB;
  ContiguousDest = DestB;
  OtherDest = DestA;
} else
  return false;

// Start building the compare and branch.

Constant *Offset = ConstantExpr::getNeg(ContiguousCases->back());
Constant *NumCases =
    ConstantInt::get(Offset->getType(), ContiguousCases->size());

Value *Sub = SI->getCondition();
if (!Offset->isNullValue())
  Sub = Builder.CreateAdd(Sub, Offset, Sub->getName() + ".off");

Value *Cmp;
// If NumCases overflowed, then all possible values jump to the successor.
if (NumCases->isNullValue() && !ContiguousCases->empty())
  Cmp = ConstantInt::getTrue(SI->getContext());
else
  Cmp = Builder.CreateICmpULT(Sub, NumCases, "switch");
BranchInst *NewBI = Builder.CreateCondBr(Cmp, ContiguousDest, OtherDest);

// Update weight for the newly-created conditional branch.
if (HasBranchWeights(SI)) {
  SmallVector<uint64_t, 8> Weights;
  GetBranchWeights(SI, Weights);
  if (Weights.size() == 1 + SI->getNumCases()) {
    uint64_t TrueWeight = 0;
    uint64_t FalseWeight = 0;
    for (size_t I = 0, E = Weights.size(); I != E; ++I) {
      if (SI->getSuccessor(I) == ContiguousDest)
        TrueWeight += Weights[I];
      else
        FalseWeight += Weights[I];
    }
    while (TrueWeight > UINT32_MAX(4294967295U) || FalseWeight > UINT32_MAX(4294967295U)) {
      TrueWeight /= 2;
      FalseWeight /= 2;
    }
    setBranchWeights(NewBI, TrueWeight, FalseWeight);
  }
}

// Prune obsolete incoming values off the successors' PHI nodes.
for (auto BBI = ContiguousDest->begin(); isa<PHINode>(BBI); ++BBI) {
  unsigned PreviousEdges = ContiguousCases->size();
  if (ContiguousDest == SI->getDefaultDest())
    ++PreviousEdges;
  for (unsigned I = 0, E = PreviousEdges - 1; I != E; ++I)
    cast<PHINode>(BBI)->removeIncomingValue(SI->getParent());
}
for (auto BBI = OtherDest->begin(); isa<PHINode>(BBI); ++BBI) {
  unsigned PreviousEdges = SI->getNumCases() - ContiguousCases->size();
  if (OtherDest == SI->getDefaultDest())
    ++PreviousEdges;
  for (unsigned I = 0, E = PreviousEdges - 1; I != E; ++I)
    cast<PHINode>(BBI)->removeIncomingValue(SI->getParent());
}

// Clean up the default block - it may have phis or other instructions before
// the unreachable terminator.
if (!HasDefault)
  createUnreachableSwitchDefault(SI, DTU);

auto *UnreachableDefault = SI->getDefaultDest();

// Drop the switch.
SI->eraseFromParent();

if (!HasDefault && DTU)
  DTU->applyUpdates({{DominatorTree::Delete, BB, UnreachableDefault}});

return true;
4974}

4976/// Compute masked bits for the condition of a switch
4977/// and use it to remove dead cases.
4978static bool eliminateDeadSwitchCases(SwitchInst *SI, DomTreeUpdater *DTU,
                                   AssumptionCache *AC,
                                   const DataLayout &DL) {
Value *Cond = SI->getCondition();
unsigned Bits = Cond->getType()->getIntegerBitWidth();
KnownBits Known = computeKnownBits(Cond, DL, 0, AC, SI);

// We can also eliminate cases by determining that their values are outside of
// the limited range of the condition based on how many significant (non-sign)
// bits are in the condition value.
unsigned ExtraSignBits = ComputeNumSignBits(Cond, DL, 0, AC, SI) - 1;
unsigned MaxSignificantBitsInCond = Bits - ExtraSignBits;

// Gather dead cases.
SmallVector<ConstantInt *, 8> DeadCases;
SmallMapVector<BasicBlock *, int, 8> NumPerSuccessorCases;
for (auto &Case : SI->cases()) {
  auto *Successor = Case.getCaseSuccessor();
  ++NumPerSuccessorCases[Successor];
  const APInt &CaseVal = Case.getCaseValue()->getValue();
  if (Known.Zero.intersects(CaseVal) || !Known.One.isSubsetOf(CaseVal) ||
      (CaseVal.getMinSignedBits() > MaxSignificantBitsInCond)) {
    DeadCases.push_back(Case.getCaseValue());
    --NumPerSuccessorCases[Successor];
    LLVM_DEBUG(dbgs() << "SimplifyCFG: switch case " << CaseValdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SimplifyCFG: switch case "
 << CaseVal << " is dead.\n"; } } while (false)
                      << " is dead.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "SimplifyCFG: switch case "
 << CaseVal << " is dead.\n"; } } while (false);
  }
}

// If we can prove that the cases must cover all possible values, the
// default destination becomes dead and we can remove it.  If we know some
// of the bits in the value, we can use that to more precisely compute the
// number of possible unique case values.
bool HasDefault =
    !isa<UnreachableInst>(SI->getDefaultDest()->getFirstNonPHIOrDbg());
const unsigned NumUnknownBits =
    Bits - (Known.Zero | Known.One).countPopulation();
assert(NumUnknownBits <= Bits)((NumUnknownBits <= Bits) ? static_cast<void> (0) : __assert_fail
 ("NumUnknownBits <= Bits", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5015, __PRETTY_FUNCTION__));
if (HasDefault && DeadCases.empty() &&
    NumUnknownBits < 64 /* avoid overflow */ &&
    SI->getNumCases() == (1ULL << NumUnknownBits)) {
  createUnreachableSwitchDefault(SI, DTU);
  return true;
}

if (DeadCases.empty())
  return false;

SwitchInstProfUpdateWrapper SIW(*SI);
for (ConstantInt *DeadCase : DeadCases) {
  SwitchInst::CaseIt CaseI = SI->findCaseValue(DeadCase);
  assert(CaseI != SI->case_default() &&((CaseI != SI->case_default() && "Case was not found. Probably mistake in DeadCases forming."
) ? static_cast<void> (0) : __assert_fail ("CaseI != SI->case_default() && \"Case was not found. Probably mistake in DeadCases forming.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5030, __PRETTY_FUNCTION__))
         "Case was not found. Probably mistake in DeadCases forming.")((CaseI != SI->case_default() && "Case was not found. Probably mistake in DeadCases forming."
) ? static_cast<void> (0) : __assert_fail ("CaseI != SI->case_default() && \"Case was not found. Probably mistake in DeadCases forming.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5030, __PRETTY_FUNCTION__));
  // Prune unused values from PHI nodes.
  CaseI->getCaseSuccessor()->removePredecessor(SI->getParent());
  SIW.removeCase(CaseI);
}

std::vector<DominatorTree::UpdateType> Updates;
for (const std::pair<BasicBlock *, int> &I : NumPerSuccessorCases)
  if (I.second == 0)
    Updates.push_back({DominatorTree::Delete, SI->getParent(), I.first});
if (DTU)
  DTU->applyUpdates(Updates);

return true;
5044}

5046/// If BB would be eligible for simplification by
5047/// TryToSimplifyUncondBranchFromEmptyBlock (i.e. it is empty and terminated
5048/// by an unconditional branch), look at the phi node for BB in the successor
5049/// block and see if the incoming value is equal to CaseValue. If so, return
5050/// the phi node, and set PhiIndex to BB's index in the phi node.
5051static PHINode *FindPHIForConditionForwarding(ConstantInt *CaseValue,
                                            BasicBlock *BB, int *PhiIndex) {
if (BB->getFirstNonPHIOrDbg() != BB->getTerminator())
  return nullptr; // BB must be empty to be a candidate for simplification.
if (!BB->getSinglePredecessor())
  return nullptr; // BB must be dominated by the switch.

BranchInst *Branch = dyn_cast<BranchInst>(BB->getTerminator());
if (!Branch || !Branch->isUnconditional())
  return nullptr; // Terminator must be unconditional branch.

BasicBlock *Succ = Branch->getSuccessor(0);

for (PHINode &PHI : Succ->phis()) {
  int Idx = PHI.getBasicBlockIndex(BB);
  assert(Idx >= 0 && "PHI has no entry for predecessor?")((Idx >= 0 && "PHI has no entry for predecessor?")
 ? static_cast<void> (0) : __assert_fail ("Idx >= 0 && \"PHI has no entry for predecessor?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5066, __PRETTY_FUNCTION__));

  Value *InValue = PHI.getIncomingValue(Idx);
  if (InValue != CaseValue)
    continue;

  *PhiIndex = Idx;
  return &PHI;
}

return nullptr;
5077}

5079/// Try to forward the condition of a switch instruction to a phi node
5080/// dominated by the switch, if that would mean that some of the destination
5081/// blocks of the switch can be folded away. Return true if a change is made.
5082static bool ForwardSwitchConditionToPHI(SwitchInst *SI) {
using ForwardingNodesMap = DenseMap<PHINode *, SmallVector<int, 4>>;

ForwardingNodesMap ForwardingNodes;
BasicBlock *SwitchBlock = SI->getParent();
bool Changed = false;
for (auto &Case : SI->cases()) {
  ConstantInt *CaseValue = Case.getCaseValue();
  BasicBlock *CaseDest = Case.getCaseSuccessor();

  // Replace phi operands in successor blocks that are using the constant case
  // value rather than the switch condition variable:
  //   switchbb:
  //   switch i32 %x, label %default [
  //     i32 17, label %succ
  //   ...
  //   succ:
  //     %r = phi i32 ... [ 17, %switchbb ] ...
  // -->
  //     %r = phi i32 ... [ %x, %switchbb ] ...

  for (PHINode &Phi : CaseDest->phis()) {
    // This only works if there is exactly 1 incoming edge from the switch to
    // a phi. If there is >1, that means multiple cases of the switch map to 1
    // value in the phi, and that phi value is not the switch condition. Thus,
    // this transform would not make sense (the phi would be invalid because
    // a phi can't have different incoming values from the same block).
    int SwitchBBIdx = Phi.getBasicBlockIndex(SwitchBlock);
    if (Phi.getIncomingValue(SwitchBBIdx) == CaseValue &&
        count(Phi.blocks(), SwitchBlock) == 1) {
      Phi.setIncomingValue(SwitchBBIdx, SI->getCondition());
      Changed = true;
    }
  }

  // Collect phi nodes that are indirectly using this switch's case constants.
  int PhiIdx;
  if (auto *Phi = FindPHIForConditionForwarding(CaseValue, CaseDest, &PhiIdx))
    ForwardingNodes[Phi].push_back(PhiIdx);
}

for (auto &ForwardingNode : ForwardingNodes) {
  PHINode *Phi = ForwardingNode.first;
  SmallVectorImpl<int> &Indexes = ForwardingNode.second;
  if (Indexes.size() < 2)
    continue;

  for (int Index : Indexes)
    Phi->setIncomingValue(Index, SI->getCondition());
  Changed = true;
}

return Changed;
5135}

5137/// Return true if the backend will be able to handle
5138/// initializing an array of constants like C.
5139static bool ValidLookupTableConstant(Constant *C, const TargetTransformInfo &TTI) {
if (C->isThreadDependent())
  return false;
if (C->isDLLImportDependent())
  return false;

if (!isa<ConstantFP>(C) && !isa<ConstantInt>(C) &&
    !isa<ConstantPointerNull>(C) && !isa<GlobalValue>(C) &&
    !isa<UndefValue>(C) && !isa<ConstantExpr>(C))
  return false;

if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
  if (!CE->isGEPWithNoNotionalOverIndexing())
    return false;
  if (!ValidLookupTableConstant(CE->getOperand(0), TTI))
    return false;
}

if (!TTI.shouldBuildLookupTablesForConstant(C))
  return false;

return true;
5161}

5163/// If V is a Constant, return it. Otherwise, try to look up
5164/// its constant value in ConstantPool, returning 0 if it's not there.
5165static Constant *
5166LookupConstant(Value *V,
             const SmallDenseMap<Value *, Constant *> &ConstantPool) {
if (Constant *C = dyn_cast<Constant>(V))
  return C;
return ConstantPool.lookup(V);
5171}

5173/// Try to fold instruction I into a constant. This works for
5174/// simple instructions such as binary operations where both operands are
5175/// constant or can be replaced by constants from the ConstantPool. Returns the
5176/// resulting constant on success, 0 otherwise.
5177static Constant *
5178ConstantFold(Instruction *I, const DataLayout &DL,
           const SmallDenseMap<Value *, Constant *> &ConstantPool) {
if (SelectInst *Select = dyn_cast<SelectInst>(I)) {
  Constant *A = LookupConstant(Select->getCondition(), ConstantPool);
  if (!A)
    return nullptr;
  if (A->isAllOnesValue())
    return LookupConstant(Select->getTrueValue(), ConstantPool);
  if (A->isNullValue())
    return LookupConstant(Select->getFalseValue(), ConstantPool);
  return nullptr;
}

SmallVector<Constant *, 4> COps;
for (unsigned N = 0, E = I->getNumOperands(); N != E; ++N) {
  if (Constant *A = LookupConstant(I->getOperand(N), ConstantPool))
    COps.push_back(A);
  else
    return nullptr;
}

if (CmpInst *Cmp = dyn_cast<CmpInst>(I)) {
  return ConstantFoldCompareInstOperands(Cmp->getPredicate(), COps[0],
                                         COps[1], DL);
}

return ConstantFoldInstOperands(I, COps, DL);
5205}

5207/// Try to determine the resulting constant values in phi nodes
5208/// at the common destination basic block, *CommonDest, for one of the case
5209/// destionations CaseDest corresponding to value CaseVal (0 for the default
5210/// case), of a switch instruction SI.
5211static bool
5212GetCaseResults(SwitchInst *SI, ConstantInt *CaseVal, BasicBlock *CaseDest,
             BasicBlock **CommonDest,
             SmallVectorImpl<std::pair<PHINode *, Constant *>> &Res,
             const DataLayout &DL, const TargetTransformInfo &TTI) {
// The block from which we enter the common destination.
BasicBlock *Pred = SI->getParent();

// If CaseDest is empty except for some side-effect free instructions through
// which we can constant-propagate the CaseVal, continue to its successor.
SmallDenseMap<Value *, Constant *> ConstantPool;
ConstantPool.insert(std::make_pair(SI->getCondition(), CaseVal));
for (Instruction &I :CaseDest->instructionsWithoutDebug()) {
  if (I.isTerminator()) {
    // If the terminator is a simple branch, continue to the next block.
    if (I.getNumSuccessors() != 1 || I.isExceptionalTerminator())
      return false;
    Pred = CaseDest;
    CaseDest = I.getSuccessor(0);
  } else if (Constant *C = ConstantFold(&I, DL, ConstantPool)) {
    // Instruction is side-effect free and constant.

    // If the instruction has uses outside this block or a phi node slot for
    // the block, it is not safe to bypass the instruction since it would then
    // no longer dominate all its uses.
    for (auto &Use : I.uses()) {
      User *User = Use.getUser();
      if (Instruction *I = dyn_cast<Instruction>(User))
        if (I->getParent() == CaseDest)
          continue;
      if (PHINode *Phi = dyn_cast<PHINode>(User))
        if (Phi->getIncomingBlock(Use) == CaseDest)
          continue;
      return false;
    }

    ConstantPool.insert(std::make_pair(&I, C));
  } else {
    break;
  }
}

// If we did not have a CommonDest before, use the current one.
if (!*CommonDest)
  *CommonDest = CaseDest;
// If the destination isn't the common one, abort.
if (CaseDest != *CommonDest)
  return false;

// Get the values for this case from phi nodes in the destination block.
for (PHINode &PHI : (*CommonDest)->phis()) {
  int Idx = PHI.getBasicBlockIndex(Pred);
  if (Idx == -1)
    continue;

  Constant *ConstVal =
      LookupConstant(PHI.getIncomingValue(Idx), ConstantPool);
  if (!ConstVal)
    return false;

  // Be conservative about which kinds of constants we support.
  if (!ValidLookupTableConstant(ConstVal, TTI))
    return false;

  Res.push_back(std::make_pair(&PHI, ConstVal));
}

return Res.size() > 0;
5279}

5281// Helper function used to add CaseVal to the list of cases that generate
5282// Result. Returns the updated number of cases that generate this result.
5283static uintptr_t MapCaseToResult(ConstantInt *CaseVal,
                               SwitchCaseResultVectorTy &UniqueResults,
                               Constant *Result) {
for (auto &I : UniqueResults) {
  if (I.first == Result) {
    I.second.push_back(CaseVal);
    return I.second.size();
  }
}
UniqueResults.push_back(
    std::make_pair(Result, SmallVector<ConstantInt *, 4>(1, CaseVal)));
return 1;
5295}

5297// Helper function that initializes a map containing
5298// results for the PHI node of the common destination block for a switch
5299// instruction. Returns false if multiple PHI nodes have been found or if
5300// there is not a common destination block for the switch.
5301static bool
5302InitializeUniqueCases(SwitchInst *SI, PHINode *&PHI, BasicBlock *&CommonDest,
                    SwitchCaseResultVectorTy &UniqueResults,
                    Constant *&DefaultResult, const DataLayout &DL,
                    const TargetTransformInfo &TTI,
                    uintptr_t MaxUniqueResults, uintptr_t MaxCasesPerResult) {
for (auto &I : SI->cases()) {
  ConstantInt *CaseVal = I.getCaseValue();

  // Resulting value at phi nodes for this case value.
  SwitchCaseResultsTy Results;
  if (!GetCaseResults(SI, CaseVal, I.getCaseSuccessor(), &CommonDest, Results,
                      DL, TTI))
    return false;

  // Only one value per case is permitted.
  if (Results.size() > 1)
    return false;

  // Add the case->result mapping to UniqueResults.
  const uintptr_t NumCasesForResult =
      MapCaseToResult(CaseVal, UniqueResults, Results.begin()->second);

  // Early out if there are too many cases for this result.
  if (NumCasesForResult > MaxCasesPerResult)
    return false;

  // Early out if there are too many unique results.
  if (UniqueResults.size() > MaxUniqueResults)
    return false;

  // Check the PHI consistency.
  if (!PHI)
    PHI = Results[0].first;
  else if (PHI != Results[0].first)
    return false;
}
// Find the default result value.
SmallVector<std::pair<PHINode *, Constant *>, 1> DefaultResults;
BasicBlock *DefaultDest = SI->getDefaultDest();
GetCaseResults(SI, nullptr, SI->getDefaultDest(), &CommonDest, DefaultResults,
               DL, TTI);
// If the default value is not found abort unless the default destination
// is unreachable.
DefaultResult =
    DefaultResults.size() == 1 ? DefaultResults.begin()->second : nullptr;
if ((!DefaultResult &&
     !isa<UnreachableInst>(DefaultDest->getFirstNonPHIOrDbg())))
  return false;

return true;
5352}

5354// Helper function that checks if it is possible to transform a switch with only
5355// two cases (or two cases + default) that produces a result into a select.
5356// Example:
5357// switch (a) {
5358//   case 10:                %0 = icmp eq i32 %a, 10
5359//     return 10;            %1 = select i1 %0, i32 10, i32 4
5360//   case 20:        ---->   %2 = icmp eq i32 %a, 20
5361//     return 2;             %3 = select i1 %2, i32 2, i32 %1
5362//   default:
5363//     return 4;
5364// }
5365static Value *ConvertTwoCaseSwitch(const SwitchCaseResultVectorTy &ResultVector,
                                 Constant *DefaultResult, Value *Condition,
                                 IRBuilder<> &Builder) {
assert(ResultVector.size() == 2 &&((ResultVector.size() == 2 && "We should have exactly two unique results at this point"
) ? static_cast<void> (0) : __assert_fail ("ResultVector.size() == 2 && \"We should have exactly two unique results at this point\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5369, __PRETTY_FUNCTION__))
       "We should have exactly two unique results at this point")((ResultVector.size() == 2 && "We should have exactly two unique results at this point"
) ? static_cast<void> (0) : __assert_fail ("ResultVector.size() == 2 && \"We should have exactly two unique results at this point\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5369, __PRETTY_FUNCTION__));
// If we are selecting between only two cases transform into a simple
// select or a two-way select if default is possible.
if (ResultVector[0].second.size() == 1 &&
    ResultVector[1].second.size() == 1) {
  ConstantInt *const FirstCase = ResultVector[0].second[0];
  ConstantInt *const SecondCase = ResultVector[1].second[0];

  bool DefaultCanTrigger = DefaultResult;
  Value *SelectValue = ResultVector[1].first;
  if (DefaultCanTrigger) {
    Value *const ValueCompare =
        Builder.CreateICmpEQ(Condition, SecondCase, "switch.selectcmp");
    SelectValue = Builder.CreateSelect(ValueCompare, ResultVector[1].first,
                                       DefaultResult, "switch.select");
  }
  Value *const ValueCompare =
      Builder.CreateICmpEQ(Condition, FirstCase, "switch.selectcmp");
  return Builder.CreateSelect(ValueCompare, ResultVector[0].first,
                              SelectValue, "switch.select");
}

return nullptr;
5392}

5394// Helper function to cleanup a switch instruction that has been converted into
5395// a select, fixing up PHI nodes and basic blocks.
5396static void RemoveSwitchAfterSelectConversion(SwitchInst *SI, PHINode *PHI,
                                            Value *SelectValue,
                                            IRBuilder<> &Builder,
                                            DomTreeUpdater *DTU) {
std::vector<DominatorTree::UpdateType> Updates;

BasicBlock *SelectBB = SI->getParent();
BasicBlock *DestBB = PHI->getParent();

if (!is_contained(predecessors(DestBB), SelectBB))
  Updates.push_back({DominatorTree::Insert, SelectBB, DestBB});
Builder.CreateBr(DestBB);

// Remove the switch.

while (PHI->getBasicBlockIndex(SelectBB) >= 0)
  PHI->removeIncomingValue(SelectBB);
PHI->addIncoming(SelectValue, SelectBB);

for (unsigned i = 0, e = SI->getNumSuccessors(); i < e; ++i) {
  BasicBlock *Succ = SI->getSuccessor(i);

  if (Succ == DestBB)
    continue;
  Succ->removePredecessor(SelectBB);
  Updates.push_back({DominatorTree::Delete, SelectBB, Succ});
}
SI->eraseFromParent();
if (DTU)
  DTU->applyUpdates(Updates);
5426}

5428/// If the switch is only used to initialize one or more
5429/// phi nodes in a common successor block with only two different
5430/// constant values, replace the switch with select.
5431static bool switchToSelect(SwitchInst *SI, IRBuilder<> &Builder,
                         DomTreeUpdater *DTU, const DataLayout &DL,
                         const TargetTransformInfo &TTI) {
Value *const Cond = SI->getCondition();
PHINode *PHI = nullptr;
BasicBlock *CommonDest = nullptr;
Constant *DefaultResult;
SwitchCaseResultVectorTy UniqueResults;
// Collect all the cases that will deliver the same value from the switch.
if (!InitializeUniqueCases(SI, PHI, CommonDest, UniqueResults, DefaultResult,
                           DL, TTI, 2, 1))
  return false;
// Selects choose between maximum two values.
if (UniqueResults.size() != 2)
  return false;
assert(PHI != nullptr && "PHI for value select not found")((PHI != nullptr && "PHI for value select not found")
 ? static_cast<void> (0) : __assert_fail ("PHI != nullptr && \"PHI for value select not found\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5446, __PRETTY_FUNCTION__));

Builder.SetInsertPoint(SI);
Value *SelectValue =
    ConvertTwoCaseSwitch(UniqueResults, DefaultResult, Cond, Builder);
if (SelectValue) {
  RemoveSwitchAfterSelectConversion(SI, PHI, SelectValue, Builder, DTU);
  return true;
}
// The switch couldn't be converted into a select.
return false;
5457}

5459namespace {

5461/// This class represents a lookup table that can be used to replace a switch.
5462class SwitchLookupTable {
5463public:
/// Create a lookup table to use as a switch replacement with the contents
/// of Values, using DefaultValue to fill any holes in the table.
SwitchLookupTable(
    Module &M, uint64_t TableSize, ConstantInt *Offset,
    const SmallVectorImpl<std::pair<ConstantInt *, Constant *>> &Values,
    Constant *DefaultValue, const DataLayout &DL, const StringRef &FuncName);

/// Build instructions with Builder to retrieve the value at
/// the position given by Index in the lookup table.
Value *BuildLookup(Value *Index, IRBuilder<> &Builder);

/// Return true if a table with TableSize elements of
/// type ElementType would fit in a target-legal register.
static bool WouldFitInRegister(const DataLayout &DL, uint64_t TableSize,
                               Type *ElementType);

5480private:
// Depending on the contents of the table, it can be represented in
// different ways.
enum {
  // For tables where each element contains the same value, we just have to
  // store that single value and return it for each lookup.
  SingleValueKind,

  // For tables where there is a linear relationship between table index
  // and values. We calculate the result with a simple multiplication
  // and addition instead of a table lookup.
  LinearMapKind,

  // For small tables with integer elements, we can pack them into a bitmap
  // that fits into a target-legal register. Values are retrieved by
  // shift and mask operations.
  BitMapKind,

  // The table is stored as an array of values. Values are retrieved by load
  // instructions from the table.
  ArrayKind
} Kind;

// For SingleValueKind, this is the single value.
Constant *SingleValue = nullptr;

// For BitMapKind, this is the bitmap.
ConstantInt *BitMap = nullptr;
IntegerType *BitMapElementTy = nullptr;

// For LinearMapKind, these are the constants used to derive the value.
ConstantInt *LinearOffset = nullptr;
ConstantInt *LinearMultiplier = nullptr;

// For ArrayKind, this is the array.
GlobalVariable *Array = nullptr;
5516};

5518} // end anonymous namespace

5520SwitchLookupTable::SwitchLookupTable(
  Module &M, uint64_t TableSize, ConstantInt *Offset,
  const SmallVectorImpl<std::pair<ConstantInt *, Constant *>> &Values,
  Constant *DefaultValue, const DataLayout &DL, const StringRef &FuncName) {
assert(Values.size() && "Can't build lookup table without values!")((Values.size() && "Can't build lookup table without values!"
) ? static_cast<void> (0) : __assert_fail ("Values.size() && \"Can't build lookup table without values!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5524, __PRETTY_FUNCTION__));
assert(TableSize >= Values.size() && "Can't fit values in table!")((TableSize >= Values.size() && "Can't fit values in table!"
) ? static_cast<void> (0) : __assert_fail ("TableSize >= Values.size() && \"Can't fit values in table!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5525, __PRETTY_FUNCTION__));

// If all values in the table are equal, this is that value.
SingleValue = Values.begin()->second;

Type *ValueType = Values.begin()->second->getType();

// Build up the table contents.
SmallVector<Constant *, 64> TableContents(TableSize);
for (size_t I = 0, E = Values.size(); I != E; ++I) {
  ConstantInt *CaseVal = Values[I].first;
  Constant *CaseRes = Values[I].second;
  assert(CaseRes->getType() == ValueType)((CaseRes->getType() == ValueType) ? static_cast<void>
 (0) : __assert_fail ("CaseRes->getType() == ValueType", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5537, __PRETTY_FUNCTION__));

  uint64_t Idx = (CaseVal->getValue() - Offset->getValue()).getLimitedValue();
  TableContents[Idx] = CaseRes;

  if (CaseRes != SingleValue)
    SingleValue = nullptr;
}

// Fill in any holes in the table with the default result.
if (Values.size() < TableSize) {
  assert(DefaultValue &&((DefaultValue && "Need a default value to fill the lookup table holes."
) ? static_cast<void> (0) : __assert_fail ("DefaultValue && \"Need a default value to fill the lookup table holes.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5549, __PRETTY_FUNCTION__))
         "Need a default value to fill the lookup table holes.")((DefaultValue && "Need a default value to fill the lookup table holes."
) ? static_cast<void> (0) : __assert_fail ("DefaultValue && \"Need a default value to fill the lookup table holes.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5549, __PRETTY_FUNCTION__));
  assert(DefaultValue->getType() == ValueType)((DefaultValue->getType() == ValueType) ? static_cast<void
> (0) : __assert_fail ("DefaultValue->getType() == ValueType"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5550, __PRETTY_FUNCTION__));
  for (uint64_t I = 0; I < TableSize; ++I) {
    if (!TableContents[I])
      TableContents[I] = DefaultValue;
  }

  if (DefaultValue != SingleValue)
    SingleValue = nullptr;
}

// If each element in the table contains the same value, we only need to store
// that single value.
if (SingleValue) {
  Kind = SingleValueKind;
  return;
}

// Check if we can derive the value with a linear transformation from the
// table index.
if (isa<IntegerType>(ValueType)) {
  bool LinearMappingPossible = true;
  APInt PrevVal;
  APInt DistToPrev;
  assert(TableSize >= 2 && "Should be a SingleValue table.")((TableSize >= 2 && "Should be a SingleValue table."
) ? static_cast<void> (0) : __assert_fail ("TableSize >= 2 && \"Should be a SingleValue table.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5573, __PRETTY_FUNCTION__));
  // Check if there is the same distance between two consecutive values.
  for (uint64_t I = 0; I < TableSize; ++I) {
    ConstantInt *ConstVal = dyn_cast<ConstantInt>(TableContents[I]);
    if (!ConstVal) {
      // This is an undef. We could deal with it, but undefs in lookup tables
      // are very seldom. It's probably not worth the additional complexity.
      LinearMappingPossible = false;
      break;
    }
    const APInt &Val = ConstVal->getValue();
    if (I != 0) {
      APInt Dist = Val - PrevVal;
      if (I == 1) {
        DistToPrev = Dist;
      } else if (Dist != DistToPrev) {
        LinearMappingPossible = false;
        break;
      }
    }
    PrevVal = Val;
  }
  if (LinearMappingPossible) {
    LinearOffset = cast<ConstantInt>(TableContents[0]);
    LinearMultiplier = ConstantInt::get(M.getContext(), DistToPrev);
    Kind = LinearMapKind;
    ++NumLinearMaps;
    return;
  }
}

// If the type is integer and the table fits in a register, build a bitmap.
if (WouldFitInRegister(DL, TableSize, ValueType)) {
  IntegerType *IT = cast<IntegerType>(ValueType);
  APInt TableInt(TableSize * IT->getBitWidth(), 0);
  for (uint64_t I = TableSize; I > 0; --I) {
    TableInt <<= IT->getBitWidth();
    // Insert values into the bitmap. Undef values are set to zero.
    if (!isa<UndefValue>(TableContents[I - 1])) {
      ConstantInt *Val = cast<ConstantInt>(TableContents[I - 1]);
      TableInt |= Val->getValue().zext(TableInt.getBitWidth());
    }
  }
  BitMap = ConstantInt::get(M.getContext(), TableInt);
  BitMapElementTy = IT;
  Kind = BitMapKind;
  ++NumBitMaps;
  return;
}

// Store the table in an array.
ArrayType *ArrayTy = ArrayType::get(ValueType, TableSize);
Constant *Initializer = ConstantArray::get(ArrayTy, TableContents);

Array = new GlobalVariable(M, ArrayTy, /*isConstant=*/true,
                           GlobalVariable::PrivateLinkage, Initializer,
                           "switch.table." + FuncName);
Array->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
// Set the alignment to that of an array items. We will be only loading one
// value out of it.
Array->setAlignment(Align(DL.getPrefTypeAlignment(ValueType)));
Kind = ArrayKind;
5635}

5637Value *SwitchLookupTable::BuildLookup(Value *Index, IRBuilder<> &Builder) {
switch (Kind) {
case SingleValueKind:
  return SingleValue;
case LinearMapKind: {
  // Derive the result value from the input value.
  Value *Result = Builder.CreateIntCast(Index, LinearMultiplier->getType(),
                                        false, "switch.idx.cast");
  if (!LinearMultiplier->isOne())
    Result = Builder.CreateMul(Result, LinearMultiplier, "switch.idx.mult");
  if (!LinearOffset->isZero())
    Result = Builder.CreateAdd(Result, LinearOffset, "switch.offset");
  return Result;
}
case BitMapKind: {
  // Type of the bitmap (e.g. i59).
  IntegerType *MapTy = BitMap->getType();

  // Cast Index to the same type as the bitmap.
  // Note: The Index is <= the number of elements in the table, so
  // truncating it to the width of the bitmask is safe.
  Value *ShiftAmt = Builder.CreateZExtOrTrunc(Index, MapTy, "switch.cast");

  // Multiply the shift amount by the element width.
  ShiftAmt = Builder.CreateMul(
      ShiftAmt, ConstantInt::get(MapTy, BitMapElementTy->getBitWidth()),
      "switch.shiftamt");

  // Shift down.
  Value *DownShifted =
      Builder.CreateLShr(BitMap, ShiftAmt, "switch.downshift");
  // Mask off.
  return Builder.CreateTrunc(DownShifted, BitMapElementTy, "switch.masked");
}
case ArrayKind: {
  // Make sure the table index will not overflow when treated as signed.
  IntegerType *IT = cast<IntegerType>(Index->getType());
  uint64_t TableSize =
      Array->getInitializer()->getType()->getArrayNumElements();
  if (TableSize > (1ULL << (IT->getBitWidth() - 1)))
    Index = Builder.CreateZExt(
        Index, IntegerType::get(IT->getContext(), IT->getBitWidth() + 1),
        "switch.tableidx.zext");

  Value *GEPIndices[] = {Builder.getInt32(0), Index};
  Value *GEP = Builder.CreateInBoundsGEP(Array->getValueType(), Array,
                                         GEPIndices, "switch.gep");
  return Builder.CreateLoad(
      cast<ArrayType>(Array->getValueType())->getElementType(), GEP,
      "switch.load");
}
}
llvm_unreachable("Unknown lookup table kind!")::llvm::llvm_unreachable_internal("Unknown lookup table kind!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5689);
5690}

5692bool SwitchLookupTable::WouldFitInRegister(const DataLayout &DL,
                                         uint64_t TableSize,
                                         Type *ElementType) {
auto *IT = dyn_cast<IntegerType>(ElementType);
if (!IT)
  return false;
// FIXME: If the type is wider than it needs to be, e.g. i8 but all values
// are <= 15, we could try to narrow the type.

// Avoid overflow, fitsInLegalInteger uses unsigned int for the width.
if (TableSize >= UINT_MAX(2147483647 *2U +1U) / IT->getBitWidth())
  return false;
return DL.fitsInLegalInteger(TableSize * IT->getBitWidth());
5705}

5707/// Determine whether a lookup table should be built for this switch, based on
5708/// the number of cases, size of the table, and the types of the results.
5709static bool
5710ShouldBuildLookupTable(SwitchInst *SI, uint64_t TableSize,
                     const TargetTransformInfo &TTI, const DataLayout &DL,
                     const SmallDenseMap<PHINode *, Type *> &ResultTypes) {
if (SI->getNumCases() > TableSize || TableSize >= UINT64_MAX(18446744073709551615UL) / 10)
  return false; // TableSize overflowed, or mul below might overflow.

bool AllTablesFitInRegister = true;
bool HasIllegalType = false;
for (const auto &I : ResultTypes) {
  Type *Ty = I.second;

  // Saturate this flag to true.
  HasIllegalType = HasIllegalType || !TTI.isTypeLegal(Ty);

  // Saturate this flag to false.
  AllTablesFitInRegister =
      AllTablesFitInRegister &&
      SwitchLookupTable::WouldFitInRegister(DL, TableSize, Ty);

  // If both flags saturate, we're done. NOTE: This *only* works with
  // saturating flags, and all flags have to saturate first due to the
  // non-deterministic behavior of iterating over a dense map.
  if (HasIllegalType && !AllTablesFitInRegister)
    break;
}

// If each table would fit in a register, we should build it anyway.
if (AllTablesFitInRegister)
  return true;

// Don't build a table that doesn't fit in-register if it has illegal types.
if (HasIllegalType)
  return false;

// The table density should be at least 40%. This is the same criterion as for
// jump tables, see SelectionDAGBuilder::handleJTSwitchCase.
// FIXME: Find the best cut-off.
return SI->getNumCases() * 10 >= TableSize * 4;
5748}

5750/// Try to reuse the switch table index compare. Following pattern:
5751/// \code
5752///     if (idx < tablesize)
5753///        r = table[idx]; // table does not contain default_value
5754///     else
5755///        r = default_value;
5756///     if (r != default_value)
5757///        ...
5758/// \endcode
5759/// Is optimized to:
5760/// \code
5761///     cond = idx < tablesize;
5762///     if (cond)
5763///        r = table[idx];
5764///     else
5765///        r = default_value;
5766///     if (cond)
5767///        ...
5768/// \endcode
5769/// Jump threading will then eliminate the second if(cond).
5770static void reuseTableCompare(
  User *PhiUser, BasicBlock *PhiBlock, BranchInst *RangeCheckBranch,
  Constant *DefaultValue,
  const SmallVectorImpl<std::pair<ConstantInt *, Constant *>> &Values) {
ICmpInst *CmpInst = dyn_cast<ICmpInst>(PhiUser);
if (!CmpInst)
  return;

// We require that the compare is in the same block as the phi so that jump
// threading can do its work afterwards.
if (CmpInst->getParent() != PhiBlock)
  return;

Constant *CmpOp1 = dyn_cast<Constant>(CmpInst->getOperand(1));
if (!CmpOp1)
  return;

Value *RangeCmp = RangeCheckBranch->getCondition();
Constant *TrueConst = ConstantInt::getTrue(RangeCmp->getType());
Constant *FalseConst = ConstantInt::getFalse(RangeCmp->getType());

// Check if the compare with the default value is constant true or false.
Constant *DefaultConst = ConstantExpr::getICmp(CmpInst->getPredicate(),
                                               DefaultValue, CmpOp1, true);
if (DefaultConst != TrueConst && DefaultConst != FalseConst)
  return;

// Check if the compare with the case values is distinct from the default
// compare result.
for (auto ValuePair : Values) {
  Constant *CaseConst = ConstantExpr::getICmp(CmpInst->getPredicate(),
                                              ValuePair.second, CmpOp1, true);
  if (!CaseConst || CaseConst == DefaultConst || isa<UndefValue>(CaseConst))
    return;
  assert((CaseConst == TrueConst || CaseConst == FalseConst) &&(((CaseConst == TrueConst || CaseConst == FalseConst) &&
 "Expect true or false as compare result.") ? static_cast<
void> (0) : __assert_fail ("(CaseConst == TrueConst || CaseConst == FalseConst) && \"Expect true or false as compare result.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5805, __PRETTY_FUNCTION__))
         "Expect true or false as compare result.")(((CaseConst == TrueConst || CaseConst == FalseConst) &&
 "Expect true or false as compare result.") ? static_cast<
void> (0) : __assert_fail ("(CaseConst == TrueConst || CaseConst == FalseConst) && \"Expect true or false as compare result.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5805, __PRETTY_FUNCTION__));
}

// Check if the branch instruction dominates the phi node. It's a simple
// dominance check, but sufficient for our needs.
// Although this check is invariant in the calling loops, it's better to do it
// at this late stage. Practically we do it at most once for a switch.
BasicBlock *BranchBlock = RangeCheckBranch->getParent();
for (auto PI = pred_begin(PhiBlock), E = pred_end(PhiBlock); PI != E; ++PI) {
  BasicBlock *Pred = *PI;
  if (Pred != BranchBlock && Pred->getUniquePredecessor() != BranchBlock)
    return;
}

if (DefaultConst == FalseConst) {
  // The compare yields the same result. We can replace it.
  CmpInst->replaceAllUsesWith(RangeCmp);
  ++NumTableCmpReuses;
} else {
  // The compare yields the same result, just inverted. We can replace it.
  Value *InvertedTableCmp = BinaryOperator::CreateXor(
      RangeCmp, ConstantInt::get(RangeCmp->getType(), 1), "inverted.cmp",
      RangeCheckBranch);
  CmpInst->replaceAllUsesWith(InvertedTableCmp);
  ++NumTableCmpReuses;
}
5831}

5833/// If the switch is only used to initialize one or more phi nodes in a common
5834/// successor block with different constant values, replace the switch with
5835/// lookup tables.
5836static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder,
                              DomTreeUpdater *DTU, const DataLayout &DL,
                              const TargetTransformInfo &TTI) {
assert(SI->getNumCases() > 1 && "Degenerate switch?")((SI->getNumCases() > 1 && "Degenerate switch?"
) ? static_cast<void> (0) : __assert_fail ("SI->getNumCases() > 1 && \"Degenerate switch?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5839, __PRETTY_FUNCTION__));

BasicBlock *BB = SI->getParent();
Function *Fn = BB->getParent();
// Only build lookup table when we have a target that supports it or the
// attribute is not set.
if (!TTI.shouldBuildLookupTables() ||
    (Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true"))
  return false;

// FIXME: If the switch is too sparse for a lookup table, perhaps we could
// split off a dense part and build a lookup table for that.

// FIXME: This creates arrays of GEPs to constant strings, which means each
// GEP needs a runtime relocation in PIC code. We should just build one big
// string and lookup indices into that.

// Ignore switches with less than three cases. Lookup tables will not make
// them faster, so we don't analyze them.
if (SI->getNumCases() < 3)
  return false;

// Figure out the corresponding result for each case value and phi node in the
// common destination, as well as the min and max case values.
assert(!SI->cases().empty())((!SI->cases().empty()) ? static_cast<void> (0) : __assert_fail
 ("!SI->cases().empty()", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5863, __PRETTY_FUNCTION__));
SwitchInst::CaseIt CI = SI->case_begin();
ConstantInt *MinCaseVal = CI->getCaseValue();
ConstantInt *MaxCaseVal = CI->getCaseValue();

BasicBlock *CommonDest = nullptr;

using ResultListTy = SmallVector<std::pair<ConstantInt *, Constant *>, 4>;
SmallDenseMap<PHINode *, ResultListTy> ResultLists;

SmallDenseMap<PHINode *, Constant *> DefaultResults;
SmallDenseMap<PHINode *, Type *> ResultTypes;
SmallVector<PHINode *, 4> PHIs;

for (SwitchInst::CaseIt E = SI->case_end(); CI != E; ++CI) {
  ConstantInt *CaseVal = CI->getCaseValue();
  if (CaseVal->getValue().slt(MinCaseVal->getValue()))
    MinCaseVal = CaseVal;
  if (CaseVal->getValue().sgt(MaxCaseVal->getValue()))
    MaxCaseVal = CaseVal;

  // Resulting value at phi nodes for this case value.
  using ResultsTy = SmallVector<std::pair<PHINode *, Constant *>, 4>;
  ResultsTy Results;
  if (!GetCaseResults(SI, CaseVal, CI->getCaseSuccessor(), &CommonDest,
                      Results, DL, TTI))
    return false;

  // Append the result from this case to the list for each phi.
  for (const auto &I : Results) {
    PHINode *PHI = I.first;
    Constant *Value = I.second;
    if (!ResultLists.count(PHI))
      PHIs.push_back(PHI);
    ResultLists[PHI].push_back(std::make_pair(CaseVal, Value));
  }
}

// Keep track of the result types.
for (PHINode *PHI : PHIs) {
  ResultTypes[PHI] = ResultLists[PHI][0].second->getType();
}

uint64_t NumResults = ResultLists[PHIs[0]].size();
APInt RangeSpread = MaxCaseVal->getValue() - MinCaseVal->getValue();
uint64_t TableSize = RangeSpread.getLimitedValue() + 1;
bool TableHasHoles = (NumResults < TableSize);

// If the table has holes, we need a constant result for the default case
// or a bitmask that fits in a register.
SmallVector<std::pair<PHINode *, Constant *>, 4> DefaultResultsList;
bool HasDefaultResults =
    GetCaseResults(SI, nullptr, SI->getDefaultDest(), &CommonDest,
                   DefaultResultsList, DL, TTI);

bool NeedMask = (TableHasHoles && !HasDefaultResults);
if (NeedMask) {
  // As an extra penalty for the validity test we require more cases.
  if (SI->getNumCases() < 4) // FIXME: Find best threshold value (benchmark).
    return false;
  if (!DL.fitsInLegalInteger(TableSize))
    return false;
}

for (const auto &I : DefaultResultsList) {
  PHINode *PHI = I.first;
  Constant *Result = I.second;
  DefaultResults[PHI] = Result;
}

if (!ShouldBuildLookupTable(SI, TableSize, TTI, DL, ResultTypes))
  return false;

std::vector<DominatorTree::UpdateType> Updates;

// Create the BB that does the lookups.
Module &Mod = *CommonDest->getParent()->getParent();
BasicBlock *LookupBB = BasicBlock::Create(
    Mod.getContext(), "switch.lookup", CommonDest->getParent(), CommonDest);

// Compute the table index value.
Builder.SetInsertPoint(SI);
Value *TableIndex;
if (MinCaseVal->isNullValue())
  TableIndex = SI->getCondition();
else
  TableIndex = Builder.CreateSub(SI->getCondition(), MinCaseVal,
                                 "switch.tableidx");

// Compute the maximum table size representable by the integer type we are
// switching upon.
unsigned CaseSize = MinCaseVal->getType()->getPrimitiveSizeInBits();
uint64_t MaxTableSize = CaseSize > 63 ? UINT64_MAX(18446744073709551615UL) : 1ULL << CaseSize;
assert(MaxTableSize >= TableSize &&((MaxTableSize >= TableSize && "It is impossible for a switch to have more entries than the max "
 "representable value of its input integer type's size.") ? static_cast
<void> (0) : __assert_fail ("MaxTableSize >= TableSize && \"It is impossible for a switch to have more entries than the max \" \"representable value of its input integer type's size.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5958, __PRETTY_FUNCTION__))
       "It is impossible for a switch to have more entries than the max "((MaxTableSize >= TableSize && "It is impossible for a switch to have more entries than the max "
 "representable value of its input integer type's size.") ? static_cast
<void> (0) : __assert_fail ("MaxTableSize >= TableSize && \"It is impossible for a switch to have more entries than the max \" \"representable value of its input integer type's size.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5958, __PRETTY_FUNCTION__))
       "representable value of its input integer type's size.")((MaxTableSize >= TableSize && "It is impossible for a switch to have more entries than the max "
 "representable value of its input integer type's size.") ? static_cast
<void> (0) : __assert_fail ("MaxTableSize >= TableSize && \"It is impossible for a switch to have more entries than the max \" \"representable value of its input integer type's size.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 5958, __PRETTY_FUNCTION__));

// If the default destination is unreachable, or if the lookup table covers
// all values of the conditional variable, branch directly to the lookup table
// BB. Otherwise, check that the condition is within the case range.
const bool DefaultIsReachable =
    !isa<UnreachableInst>(SI->getDefaultDest()->getFirstNonPHIOrDbg());
const bool GeneratingCoveredLookupTable = (MaxTableSize == TableSize);
BranchInst *RangeCheckBranch = nullptr;

if (!DefaultIsReachable || GeneratingCoveredLookupTable) {
  Builder.CreateBr(LookupBB);
  Updates.push_back({DominatorTree::Insert, BB, LookupBB});
  // Note: We call removeProdecessor later since we need to be able to get the
  // PHI value for the default case in case we're using a bit mask.
} else {
  Value *Cmp = Builder.CreateICmpULT(
      TableIndex, ConstantInt::get(MinCaseVal->getType(), TableSize));
  RangeCheckBranch =
      Builder.CreateCondBr(Cmp, LookupBB, SI->getDefaultDest());
  Updates.push_back({DominatorTree::Insert, BB, LookupBB});
}

// Populate the BB that does the lookups.
Builder.SetInsertPoint(LookupBB);

if (NeedMask) {
  // Before doing the lookup, we do the hole check. The LookupBB is therefore
  // re-purposed to do the hole check, and we create a new LookupBB.
  BasicBlock *MaskBB = LookupBB;
  MaskBB->setName("switch.hole_check");
  LookupBB = BasicBlock::Create(Mod.getContext(), "switch.lookup",
                                CommonDest->getParent(), CommonDest);

  // Make the mask's bitwidth at least 8-bit and a power-of-2 to avoid
  // unnecessary illegal types.
  uint64_t TableSizePowOf2 = NextPowerOf2(std::max(7ULL, TableSize - 1ULL));
  APInt MaskInt(TableSizePowOf2, 0);
  APInt One(TableSizePowOf2, 1);
  // Build bitmask; fill in a 1 bit for every case.
  const ResultListTy &ResultList = ResultLists[PHIs[0]];
  for (size_t I = 0, E = ResultList.size(); I != E; ++I) {
    uint64_t Idx = (ResultList[I].first->getValue() - MinCaseVal->getValue())
                       .getLimitedValue();
    MaskInt |= One << Idx;
  }
  ConstantInt *TableMask = ConstantInt::get(Mod.getContext(), MaskInt);

  // Get the TableIndex'th bit of the bitmask.
  // If this bit is 0 (meaning hole) jump to the default destination,
  // else continue with table lookup.
  IntegerType *MapTy = TableMask->getType();
  Value *MaskIndex =
      Builder.CreateZExtOrTrunc(TableIndex, MapTy, "switch.maskindex");
  Value *Shifted = Builder.CreateLShr(TableMask, MaskIndex, "switch.shifted");
  Value *LoBit = Builder.CreateTrunc(
      Shifted, Type::getInt1Ty(Mod.getContext()), "switch.lobit");
  Builder.CreateCondBr(LoBit, LookupBB, SI->getDefaultDest());
  Updates.push_back({DominatorTree::Insert, MaskBB, LookupBB});
  Updates.push_back({DominatorTree::Insert, MaskBB, SI->getDefaultDest()});
  Builder.SetInsertPoint(LookupBB);
  AddPredecessorToBlock(SI->getDefaultDest(), MaskBB, BB);
}

if (!DefaultIsReachable || GeneratingCoveredLookupTable) {
  // We cached PHINodes in PHIs. To avoid accessing deleted PHINodes later,
  // do not delete PHINodes here.
  SI->getDefaultDest()->removePredecessor(BB,
                                          /*KeepOneInputPHIs=*/true);
  Updates.push_back({DominatorTree::Delete, BB, SI->getDefaultDest()});
}

bool ReturnedEarly = false;
for (PHINode *PHI : PHIs) {
  const ResultListTy &ResultList = ResultLists[PHI];

  // If using a bitmask, use any value to fill the lookup table holes.
  Constant *DV = NeedMask ? ResultLists[PHI][0].second : DefaultResults[PHI];
  StringRef FuncName = Fn->getName();
  SwitchLookupTable Table(Mod, TableSize, MinCaseVal, ResultList, DV, DL,
                          FuncName);

  Value *Result = Table.BuildLookup(TableIndex, Builder);

  // If the result is used to return immediately from the function, we want to
  // do that right here.
  if (PHI->hasOneUse() && isa<ReturnInst>(*PHI->user_begin()) &&
      PHI->user_back() == CommonDest->getFirstNonPHIOrDbg()) {
    Builder.CreateRet(Result);
    ReturnedEarly = true;
    break;
  }

  // Do a small peephole optimization: re-use the switch table compare if
  // possible.
  if (!TableHasHoles && HasDefaultResults && RangeCheckBranch) {
    BasicBlock *PhiBlock = PHI->getParent();
    // Search for compare instructions which use the phi.
    for (auto *User : PHI->users()) {
      reuseTableCompare(User, PhiBlock, RangeCheckBranch, DV, ResultList);
    }
  }

  PHI->addIncoming(Result, LookupBB);
}

if (!ReturnedEarly) {
  Builder.CreateBr(CommonDest);
  Updates.push_back({DominatorTree::Insert, LookupBB, CommonDest});
}

// Remove the switch.
SmallSetVector<BasicBlock *, 8> RemovedSuccessors;
for (unsigned i = 0, e = SI->getNumSuccessors(); i < e; ++i) {
  BasicBlock *Succ = SI->getSuccessor(i);

  if (Succ == SI->getDefaultDest())
    continue;
  Succ->removePredecessor(BB);
  RemovedSuccessors.insert(Succ);
}
SI->eraseFromParent();

if (DTU) {
  for (BasicBlock *RemovedSuccessor : RemovedSuccessors)
    Updates.push_back({DominatorTree::Delete, BB, RemovedSuccessor});
  DTU->applyUpdates(Updates);
}

++NumLookupTables;
if (NeedMask)
  ++NumLookupTablesHoles;
return true;
6091}

6093static bool isSwitchDense(ArrayRef<int64_t> Values) {
// See also SelectionDAGBuilder::isDense(), which this function was based on.
uint64_t Diff = (uint64_t)Values.back() - (uint64_t)Values.front();
uint64_t Range = Diff + 1;
uint64_t NumCases = Values.size();
// 40% is the default density for building a jump table in optsize/minsize mode.
uint64_t MinDensity = 40;

return NumCases * 100 >= Range * MinDensity;
6102}

6104/// Try to transform a switch that has "holes" in it to a contiguous sequence
6105/// of cases.
6106///
6107/// A switch such as: switch(i) {case 5: case 9: case 13: case 17:} can be
6108/// range-reduced to: switch ((i-5) / 4) {case 0: case 1: case 2: case 3:}.
6109///
6110/// This converts a sparse switch into a dense switch which allows better
6111/// lowering and could also allow transforming into a lookup table.
6112static bool ReduceSwitchRange(SwitchInst *SI, IRBuilder<> &Builder,
                            const DataLayout &DL,
                            const TargetTransformInfo &TTI) {
auto *CondTy = cast<IntegerType>(SI->getCondition()->getType());
if (CondTy->getIntegerBitWidth() > 64 ||
    !DL.fitsInLegalInteger(CondTy->getIntegerBitWidth()))
  return false;
// Only bother with this optimization if there are more than 3 switch cases;
// SDAG will only bother creating jump tables for 4 or more cases.
if (SI->getNumCases() < 4)
  return false;

// This transform is agnostic to the signedness of the input or case values. We
// can treat the case values as signed or unsigned. We can optimize more common
// cases such as a sequence crossing zero {-4,0,4,8} if we interpret case values
// as signed.
SmallVector<int64_t,4> Values;
for (auto &C : SI->cases())
  Values.push_back(C.getCaseValue()->getValue().getSExtValue());
llvm::sort(Values);

// If the switch is already dense, there's nothing useful to do here.
if (isSwitchDense(Values))
  return false;

// First, transform the values such that they start at zero and ascend.
int64_t Base = Values[0];
for (auto &V : Values)
  V -= (uint64_t)(Base);

// Now we have signed numbers that have been shifted so that, given enough
// precision, there are no negative values. Since the rest of the transform
// is bitwise only, we switch now to an unsigned representation.

// This transform can be done speculatively because it is so cheap - it
// results in a single rotate operation being inserted.
// FIXME: It's possible that optimizing a switch on powers of two might also
// be beneficial - flag values are often powers of two and we could use a CLZ
// as the key function.

// countTrailingZeros(0) returns 64. As Values is guaranteed to have more than
// one element and LLVM disallows duplicate cases, Shift is guaranteed to be
// less than 64.
unsigned Shift = 64;
for (auto &V : Values)
  Shift = std::min(Shift, countTrailingZeros((uint64_t)V));
assert(Shift < 64)((Shift < 64) ? static_cast<void> (0) : __assert_fail
 ("Shift < 64", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6158, __PRETTY_FUNCTION__));
if (Shift > 0)
  for (auto &V : Values)
    V = (int64_t)((uint64_t)V >> Shift);

if (!isSwitchDense(Values))
  // Transform didn't create a dense switch.
  return false;

// The obvious transform is to shift the switch condition right and emit a
// check that the condition actually cleanly divided by GCD, i.e.
//   C & (1 << Shift - 1) == 0
// inserting a new CFG edge to handle the case where it didn't divide cleanly.
//
// A cheaper way of doing this is a simple ROTR(C, Shift). This performs the
// shift and puts the shifted-off bits in the uppermost bits. If any of these
// are nonzero then the switch condition will be very large and will hit the
// default case.

auto *Ty = cast<IntegerType>(SI->getCondition()->getType());
Builder.SetInsertPoint(SI);
auto *ShiftC = ConstantInt::get(Ty, Shift);
auto *Sub = Builder.CreateSub(SI->getCondition(), ConstantInt::get(Ty, Base));
auto *LShr = Builder.CreateLShr(Sub, ShiftC);
auto *Shl = Builder.CreateShl(Sub, Ty->getBitWidth() - Shift);
auto *Rot = Builder.CreateOr(LShr, Shl);
SI->replaceUsesOfWith(SI->getCondition(), Rot);

for (auto Case : SI->cases()) {
  auto *Orig = Case.getCaseValue();
  auto Sub = Orig->getValue() - APInt(Ty->getBitWidth(), Base);
  Case.setValue(
      cast<ConstantInt>(ConstantInt::get(Ty, Sub.lshr(ShiftC->getValue()))));
}
return true;
6193}

6195bool SimplifyCFGOpt::simplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) {
BasicBlock *BB = SI->getParent();

if (isValueEqualityComparison(SI)) {
  // If we only have one predecessor, and if it is a branch on this value,
  // see if that predecessor totally determines the outcome of this switch.
  if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
    if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
      return requestResimplify();

  Value *Cond = SI->getCondition();
  if (SelectInst *Select = dyn_cast<SelectInst>(Cond))
    if (SimplifySwitchOnSelect(SI, Select))
      return requestResimplify();

  // If the block only contains the switch, see if we can fold the block
  // away into any preds.
  if (SI == &*BB->instructionsWithoutDebug().begin())
    if (FoldValueComparisonIntoPredecessors(SI, Builder))
      return requestResimplify();
}

// Try to transform the switch into an icmp and a branch.
if (TurnSwitchRangeIntoICmp(SI, Builder))
  return requestResimplify();

// Remove unreachable cases.
if (eliminateDeadSwitchCases(SI, DTU, Options.AC, DL))
  return requestResimplify();

if (switchToSelect(SI, Builder, DTU, DL, TTI))
  return requestResimplify();

if (Options.ForwardSwitchCondToPhi && ForwardSwitchConditionToPHI(SI))
  return requestResimplify();

// The conversion from switch to lookup tables results in difficult-to-analyze
// code and makes pruning branches much harder. This is a problem if the
// switch expression itself can still be restricted as a result of inlining or
// CVP. Therefore, only apply this transformation during late stages of the
// optimisation pipeline.
if (Options.ConvertSwitchToLookupTable &&
    SwitchToLookupTable(SI, Builder, DTU, DL, TTI))
  return requestResimplify();

if (ReduceSwitchRange(SI, Builder, DL, TTI))
  return requestResimplify();

return false;
6244}

6246bool SimplifyCFGOpt::simplifyIndirectBr(IndirectBrInst *IBI) {
BasicBlock *BB = IBI->getParent();
bool Changed = false;

// Eliminate redundant destinations.
SmallPtrSet<Value *, 8> Succs;
SmallSetVector<BasicBlock *, 8> RemovedSuccs;
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
  BasicBlock *Dest = IBI->getDestination(i);
  if (!Dest->hasAddressTaken() || !Succs.insert(Dest).second) {
    if (!Dest->hasAddressTaken())
      RemovedSuccs.insert(Dest);
    Dest->removePredecessor(BB);
    IBI->removeDestination(i);
    --i;
    --e;
    Changed = true;
  }
}

if (DTU) {
  std::vector<DominatorTree::UpdateType> Updates;
  Updates.reserve(RemovedSuccs.size());
  for (auto *RemovedSucc : RemovedSuccs)
    Updates.push_back({DominatorTree::Delete, BB, RemovedSucc});
  DTU->applyUpdates(Updates);
}

if (IBI->getNumDestinations() == 0) {
  // If the indirectbr has no successors, change it to unreachable.
  new UnreachableInst(IBI->getContext(), IBI);
  EraseTerminatorAndDCECond(IBI);
  return true;
}

if (IBI->getNumDestinations() == 1) {
  // If the indirectbr has one successor, change it to a direct branch.
  BranchInst::Create(IBI->getDestination(0), IBI);
  EraseTerminatorAndDCECond(IBI);
  return true;
}

if (SelectInst *SI = dyn_cast<SelectInst>(IBI->getAddress())) {
  if (SimplifyIndirectBrOnSelect(IBI, SI))
    return requestResimplify();
}
return Changed;
6293}

6295/// Given an block with only a single landing pad and a unconditional branch
6296/// try to find another basic block which this one can be merged with.  This
6297/// handles cases where we have multiple invokes with unique landing pads, but
6298/// a shared handler.
6299///
6300/// We specifically choose to not worry about merging non-empty blocks
6301/// here.  That is a PRE/scheduling problem and is best solved elsewhere.  In
6302/// practice, the optimizer produces empty landing pad blocks quite frequently
6303/// when dealing with exception dense code.  (see: instcombine, gvn, if-else
6304/// sinking in this file)
6305///
6306/// This is primarily a code size optimization.  We need to avoid performing
6307/// any transform which might inhibit optimization (such as our ability to
6308/// specialize a particular handler via tail commoning).  We do this by not
6309/// merging any blocks which require us to introduce a phi.  Since the same
6310/// values are flowing through both blocks, we don't lose any ability to
6311/// specialize.  If anything, we make such specialization more likely.
6312///
6313/// TODO - This transformation could remove entries from a phi in the target
6314/// block when the inputs in the phi are the same for the two blocks being
6315/// merged.  In some cases, this could result in removal of the PHI entirely.
6316static bool TryToMergeLandingPad(LandingPadInst *LPad, BranchInst *BI,
                               BasicBlock *BB, DomTreeUpdater *DTU) {
auto Succ = BB->getUniqueSuccessor();
assert(Succ)((Succ) ? static_cast<void> (0) : __assert_fail ("Succ"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6319, __PRETTY_FUNCTION__));
// If there's a phi in the successor block, we'd likely have to introduce
// a phi into the merged landing pad block.
if (isa<PHINode>(*Succ->begin()))
  return false;

for (BasicBlock *OtherPred : predecessors(Succ)) {
  if (BB == OtherPred)
    continue;
  BasicBlock::iterator I = OtherPred->begin();
  LandingPadInst *LPad2 = dyn_cast<LandingPadInst>(I);
  if (!LPad2 || !LPad2->isIdenticalTo(LPad))
    continue;
  for (++I; isa<DbgInfoIntrinsic>(I); ++I)
    ;
  BranchInst *BI2 = dyn_cast<BranchInst>(I);
  if (!BI2 || !BI2->isIdenticalTo(BI))
    continue;

  std::vector<DominatorTree::UpdateType> Updates;

  // We've found an identical block.  Update our predecessors to take that
  // path instead and make ourselves dead.
  SmallPtrSet<BasicBlock *, 16> Preds;
  Preds.insert(pred_begin(BB), pred_end(BB));
  for (BasicBlock *Pred : Preds) {
    InvokeInst *II = cast<InvokeInst>(Pred->getTerminator());
    assert(II->getNormalDest() != BB && II->getUnwindDest() == BB &&((II->getNormalDest() != BB && II->getUnwindDest
() == BB && "unexpected successor") ? static_cast<
void> (0) : __assert_fail ("II->getNormalDest() != BB && II->getUnwindDest() == BB && \"unexpected successor\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6347, __PRETTY_FUNCTION__))
           "unexpected successor")((II->getNormalDest() != BB && II->getUnwindDest
() == BB && "unexpected successor") ? static_cast<
void> (0) : __assert_fail ("II->getNormalDest() != BB && II->getUnwindDest() == BB && \"unexpected successor\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6347, __PRETTY_FUNCTION__));
    II->setUnwindDest(OtherPred);
    Updates.push_back({DominatorTree::Insert, Pred, OtherPred});
    Updates.push_back({DominatorTree::Delete, Pred, BB});
  }

  // The debug info in OtherPred doesn't cover the merged control flow that
  // used to go through BB.  We need to delete it or update it.
  for (auto I = OtherPred->begin(), E = OtherPred->end(); I != E;) {
    Instruction &Inst = *I;
    I++;
    if (isa<DbgInfoIntrinsic>(Inst))
      Inst.eraseFromParent();
  }

  SmallPtrSet<BasicBlock *, 16> Succs;
  Succs.insert(succ_begin(BB), succ_end(BB));
  for (BasicBlock *Succ : Succs) {
    Succ->removePredecessor(BB);
    Updates.push_back({DominatorTree::Delete, BB, Succ});
  }

  IRBuilder<> Builder(BI);
  Builder.CreateUnreachable();
  BI->eraseFromParent();
  if (DTU)
    DTU->applyUpdates(Updates);
  return true;
}
return false;
6377}

6379bool SimplifyCFGOpt::simplifyBranch(BranchInst *Branch, IRBuilder<> &Builder) {
return Branch->isUnconditional() ? simplifyUncondBranch(Branch, Builder)
                                 : simplifyCondBranch(Branch, Builder);
6382}

6384bool SimplifyCFGOpt::simplifyUncondBranch(BranchInst *BI,
                                        IRBuilder<> &Builder) {
BasicBlock *BB = BI->getParent();
BasicBlock *Succ = BI->getSuccessor(0);

// If the Terminator is the only non-phi instruction, simplify the block.
// If LoopHeader is provided, check if the block or its successor is a loop
// header. (This is for early invocations before loop simplify and
// vectorization to keep canonical loop forms for nested loops. These blocks
// can be eliminated when the pass is invoked later in the back-end.)
// Note that if BB has only one predecessor then we do not introduce new
// backedge, so we can eliminate BB.
bool NeedCanonicalLoop =
    Options.NeedCanonicalLoop &&
    (LoopHeaders && BB->hasNPredecessorsOrMore(2) &&
     (LoopHeaders->count(BB) || LoopHeaders->count(Succ)));
BasicBlock::iterator I = BB->getFirstNonPHIOrDbg()->getIterator();
if (I->isTerminator() && BB != &BB->getParent()->getEntryBlock() &&
    !NeedCanonicalLoop && TryToSimplifyUncondBranchFromEmptyBlock(BB, DTU))
  return true;

// If the only instruction in the block is a seteq/setne comparison against a
// constant, try to simplify the block.
if (ICmpInst *ICI = dyn_cast<ICmpInst>(I))
  if (ICI->isEquality() && isa<ConstantInt>(ICI->getOperand(1))) {
    for (++I; isa<DbgInfoIntrinsic>(I); ++I)
      ;
    if (I->isTerminator() &&
        tryToSimplifyUncondBranchWithICmpInIt(ICI, Builder))
      return true;
  }

// See if we can merge an empty landing pad block with another which is
// equivalent.
if (LandingPadInst *LPad = dyn_cast<LandingPadInst>(I)) {
  for (++I; isa<DbgInfoIntrinsic>(I); ++I)
    ;
  if (I->isTerminator() && TryToMergeLandingPad(LPad, BI, BB, DTU))
    return true;
}

// If this basic block is ONLY a compare and a branch, and if a predecessor
// branches to us and our successor, fold the comparison into the
// predecessor and use logical operations to update the incoming value
// for PHI nodes in common successor.
if (FoldBranchToCommonDest(BI, DTU, /*MSSAU=*/nullptr, &TTI,
                           Options.BonusInstThreshold))
  return requestResimplify();
return false;
6433}

6435static BasicBlock *allPredecessorsComeFromSameSource(BasicBlock *BB) {
BasicBlock *PredPred = nullptr;
for (auto *P : predecessors(BB)) {
  BasicBlock *PPred = P->getSinglePredecessor();
  if (!PPred || (PredPred && PredPred != PPred))
    return nullptr;
  PredPred = PPred;
}
return PredPred;
6444}

6446bool SimplifyCFGOpt::simplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) {
BasicBlock *BB = BI->getParent();
if (!Options.SimplifyCondBranch)
  return false;

// Conditional branch
if (isValueEqualityComparison(BI)) {
  // If we only have one predecessor, and if it is a branch on this value,
  // see if that predecessor totally determines the outcome of this
  // switch.
  if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
    if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred, Builder))
      return requestResimplify();

  // This block must be empty, except for the setcond inst, if it exists.
  // Ignore dbg intrinsics.
  auto I = BB->instructionsWithoutDebug().begin();
  if (&*I == BI) {
    if (FoldValueComparisonIntoPredecessors(BI, Builder))
      return requestResimplify();
  } else if (&*I == cast<Instruction>(BI->getCondition())) {
    ++I;
    if (&*I == BI && FoldValueComparisonIntoPredecessors(BI, Builder))
      return requestResimplify();
  }
}

// Try to turn "br (X == 0 | X == 1), T, F" into a switch instruction.
if (SimplifyBranchOnICmpChain(BI, Builder, DL))
  return true;

// If this basic block has dominating predecessor blocks and the dominating
// blocks' conditions imply BI's condition, we know the direction of BI.
Optional<bool> Imp = isImpliedByDomCondition(BI->getCondition(), BI, DL);
if (Imp) {
  // Turn this into a branch on constant.
  auto *OldCond = BI->getCondition();
  ConstantInt *TorF = *Imp ? ConstantInt::getTrue(BB->getContext())
                           : ConstantInt::getFalse(BB->getContext());
  BI->setCondition(TorF);
  RecursivelyDeleteTriviallyDeadInstructions(OldCond);
  return requestResimplify();
}

// If this basic block is ONLY a compare and a branch, and if a predecessor
// branches to us and one of our successors, fold the comparison into the
// predecessor and use logical operations to pick the right destination.
if (FoldBranchToCommonDest(BI, DTU, /*MSSAU=*/nullptr, &TTI,
                           Options.BonusInstThreshold))
  return requestResimplify();

// We have a conditional branch to two blocks that are only reachable
// from BI.  We know that the condbr dominates the two blocks, so see if
// there is any identical code in the "then" and "else" blocks.  If so, we
// can hoist it up to the branching block.
if (BI->getSuccessor(0)->getSinglePredecessor()) {
  if (BI->getSuccessor(1)->getSinglePredecessor()) {
    if (HoistCommon && Options.HoistCommonInsts)
      if (HoistThenElseCodeToIf(BI, TTI))
        return requestResimplify();
  } else {
    // If Successor #1 has multiple preds, we may be able to conditionally
    // execute Successor #0 if it branches to Successor #1.
    Instruction *Succ0TI = BI->getSuccessor(0)->getTerminator();
    if (Succ0TI->getNumSuccessors() == 1 &&
        Succ0TI->getSuccessor(0) == BI->getSuccessor(1))
      if (SpeculativelyExecuteBB(BI, BI->getSuccessor(0), TTI))
        return requestResimplify();
  }
} else if (BI->getSuccessor(1)->getSinglePredecessor()) {
  // If Successor #0 has multiple preds, we may be able to conditionally
  // execute Successor #1 if it branches to Successor #0.
  Instruction *Succ1TI = BI->getSuccessor(1)->getTerminator();
  if (Succ1TI->getNumSuccessors() == 1 &&
      Succ1TI->getSuccessor(0) == BI->getSuccessor(0))
    if (SpeculativelyExecuteBB(BI, BI->getSuccessor(1), TTI))
      return requestResimplify();
}

// If this is a branch on a phi node in the current block, thread control
// through this block if any PHI node entries are constants.
if (PHINode *PN = dyn_cast<PHINode>(BI->getCondition()))
  if (PN->getParent() == BI->getParent())
    if (FoldCondBranchOnPHI(BI, DTU, DL, Options.AC))
      return requestResimplify();

// Scan predecessor blocks for conditional branches.
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
  if (BranchInst *PBI = dyn_cast<BranchInst>((*PI)->getTerminator()))
    if (PBI != BI && PBI->isConditional())
      if (SimplifyCondBranchToCondBranch(PBI, BI, DTU, DL, TTI))
        return requestResimplify();

// Look for diamond patterns.
if (MergeCondStores)
  if (BasicBlock *PrevBB = allPredecessorsComeFromSameSource(BB))
    if (BranchInst *PBI = dyn_cast<BranchInst>(PrevBB->getTerminator()))
      if (PBI != BI && PBI->isConditional())
        if (mergeConditionalStores(PBI, BI, DTU, DL, TTI))
          return requestResimplify();

return false;
6548}

6550/// Check if passing a value to an instruction will cause undefined behavior.
6551static bool passingValueIsAlwaysUndefined(Value *V, Instruction *I, bool PtrValueMayBeModified) {
Constant *C = dyn_cast<Constant>(V);
if (!C)
  return false;

if (I->use_empty())
  return false;

if (C->isNullValue() || isa<UndefValue>(C)) {
  // Only look at the first use, avoid hurting compile time with long uselists
  User *Use = *I->user_begin();

  // Now make sure that there are no instructions in between that can alter
  // control flow (eg. calls)
  for (BasicBlock::iterator
           i = ++BasicBlock::iterator(I),
           UI = BasicBlock::iterator(dyn_cast<Instruction>(Use));
       i != UI; ++i)
    if (i == I->getParent()->end() || i->mayHaveSideEffects())
      return false;

  // Look through GEPs. A load from a GEP derived from NULL is still undefined
  if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Use))
    if (GEP->getPointerOperand() == I) {
      if (!GEP->isInBounds() || !GEP->hasAllZeroIndices())
        PtrValueMayBeModified = true;
      return passingValueIsAlwaysUndefined(V, GEP, PtrValueMayBeModified);
    }

  // Look through bitcasts.
  if (BitCastInst *BC = dyn_cast<BitCastInst>(Use))
    return passingValueIsAlwaysUndefined(V, BC, PtrValueMayBeModified);

  // Load from null is undefined.
  if (LoadInst *LI = dyn_cast<LoadInst>(Use))
    if (!LI->isVolatile())
      return !NullPointerIsDefined(LI->getFunction(),
                                   LI->getPointerAddressSpace());

  // Store to null is undefined.
  if (StoreInst *SI = dyn_cast<StoreInst>(Use))
    if (!SI->isVolatile())
      return (!NullPointerIsDefined(SI->getFunction(),
                                    SI->getPointerAddressSpace())) &&
             SI->getPointerOperand() == I;

  if (auto *CB = dyn_cast<CallBase>(Use)) {
    if (C->isNullValue() && NullPointerIsDefined(CB->getFunction()))
      return false;
    // A call to null is undefined.
    if (CB->getCalledOperand() == I)
      return true;

    if (C->isNullValue()) {
      for (const llvm::Use &Arg : CB->args())
        if (Arg == I) {
          unsigned ArgIdx = CB->getArgOperandNo(&Arg);
          if (CB->paramHasAttr(ArgIdx, Attribute::NonNull) &&
              CB->paramHasAttr(ArgIdx, Attribute::NoUndef)) {
            // Passing null to a nonnnull+noundef argument is undefined.
            return !PtrValueMayBeModified;
          }
        }
    } else if (isa<UndefValue>(C)) {
      // Passing undef to a noundef argument is undefined.
      for (const llvm::Use &Arg : CB->args())
        if (Arg == I) {
          unsigned ArgIdx = CB->getArgOperandNo(&Arg);
          if (CB->paramHasAttr(ArgIdx, Attribute::NoUndef)) {
            // Passing undef to a noundef argument is undefined.
            return true;
          }
        }
    }
  }
}
return false;
6628}

6630/// If BB has an incoming value that will always trigger undefined behavior
6631/// (eg. null pointer dereference), remove the branch leading here.
6632static bool removeUndefIntroducingPredecessor(BasicBlock *BB,
                                            DomTreeUpdater *DTU) {
for (PHINode &PHI : BB->phis())
  for (unsigned i = 0, e = PHI.getNumIncomingValues(); i != e; ++i)
    if (passingValueIsAlwaysUndefined(PHI.getIncomingValue(i), &PHI)) {
      BasicBlock *Predecessor = PHI.getIncomingBlock(i);
      Instruction *T = Predecessor->getTerminator();
      IRBuilder<> Builder(T);
      if (BranchInst *BI = dyn_cast<BranchInst>(T)) {
        BB->removePredecessor(Predecessor);
        // Turn uncoditional branches into unreachables and remove the dead
        // destination from conditional branches.
        if (BI->isUnconditional())
          Builder.CreateUnreachable();
        else
          Builder.CreateBr(BI->getSuccessor(0) == BB ? BI->getSuccessor(1)
                                                     : BI->getSuccessor(0));
        BI->eraseFromParent();
        if (DTU)
          DTU->applyUpdates({{DominatorTree::Delete, Predecessor, BB}});
        return true;
      }
      // TODO: SwitchInst.
    }

return false;
6658}

6660bool SimplifyCFGOpt::simplifyOnceImpl(BasicBlock *BB) {
bool Changed = false;

assert(BB && BB->getParent() && "Block not embedded in function!")((BB && BB->getParent() && "Block not embedded in function!"
) ? static_cast<void> (0) : __assert_fail ("BB && BB->getParent() && \"Block not embedded in function!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6663, __PRETTY_FUNCTION__));
assert(BB->getTerminator() && "Degenerate basic block encountered!")((BB->getTerminator() && "Degenerate basic block encountered!"
) ? static_cast<void> (0) : __assert_fail ("BB->getTerminator() && \"Degenerate basic block encountered!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6664, __PRETTY_FUNCTION__));

// Remove basic blocks that have no predecessors (except the entry block)...
// or that just have themself as a predecessor.  These are unreachable.
if ((pred_empty(BB) && BB != &BB->getParent()->getEntryBlock()) ||
    BB->getSinglePredecessor() == BB) {
  LLVM_DEBUG(dbgs() << "Removing BB: \n" << *BB)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("simplifycfg")) { dbgs() << "Removing BB: \n" <<
 *BB; } } while (false);
  DeleteDeadBlock(BB, DTU);
  return true;
}

// Check to see if we can constant propagate this terminator instruction
// away...
Changed |= ConstantFoldTerminator(BB, /*DeleteDeadConditions=*/true,
                                  /*TLI=*/nullptr, DTU);

// Check for and eliminate duplicate PHI nodes in this block.
Changed |= EliminateDuplicatePHINodes(BB);

// Check for and remove branches that will always cause undefined behavior.
Changed |= removeUndefIntroducingPredecessor(BB, DTU);

// Merge basic blocks into their predecessor if there is only one distinct
// pred, and if there is only one distinct successor of the predecessor, and
// if there are no PHI nodes.
if (MergeBlockIntoPredecessor(BB, DTU))
  return true;

if (SinkCommon && Options.SinkCommonInsts)
  Changed |= SinkCommonCodeFromPredecessors(BB, DTU);

IRBuilder<> Builder(BB);

if (Options.FoldTwoEntryPHINode) {
  // If there is a trivial two-entry PHI node in this basic block, and we can
  // eliminate it, do so now.
  if (auto *PN = dyn_cast<PHINode>(BB->begin()))
    if (PN->getNumIncomingValues() == 2)
      Changed |= FoldTwoEntryPHINode(PN, TTI, DTU, DL);
}

Instruction *Terminator = BB->getTerminator();
Builder.SetInsertPoint(Terminator);
switch (Terminator->getOpcode()) {
case Instruction::Br:
  Changed |= simplifyBranch(cast<BranchInst>(Terminator), Builder);
  break;
case Instruction::Ret:
  Changed |= simplifyReturn(cast<ReturnInst>(Terminator), Builder);
  break;
case Instruction::Resume:
  Changed |= simplifyResume(cast<ResumeInst>(Terminator), Builder);
  break;
case Instruction::CleanupRet:
  Changed |= simplifyCleanupReturn(cast<CleanupReturnInst>(Terminator));
  break;
case Instruction::Switch:
  Changed |= simplifySwitch(cast<SwitchInst>(Terminator), Builder);
  break;
case Instruction::Unreachable:
  Changed |= simplifyUnreachable(cast<UnreachableInst>(Terminator));
  break;
case Instruction::IndirectBr:
  Changed |= simplifyIndirectBr(cast<IndirectBrInst>(Terminator));
  break;
}

return Changed;
6732}

6734bool SimplifyCFGOpt::simplifyOnce(BasicBlock *BB) {
bool Changed = simplifyOnceImpl(BB);

assert((!RequireAndPreserveDomTree ||(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Failed to maintain validity of domtree!") ? static_cast<
void> (0) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Failed to maintain validity of domtree!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6740, __PRETTY_FUNCTION__))
        (DTU &&(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Failed to maintain validity of domtree!") ? static_cast<
void> (0) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Failed to maintain validity of domtree!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6740, __PRETTY_FUNCTION__))
         DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) &&(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Failed to maintain validity of domtree!") ? static_cast<
void> (0) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Failed to maintain validity of domtree!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6740, __PRETTY_FUNCTION__))
       "Failed to maintain validity of domtree!")(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Failed to maintain validity of domtree!") ? static_cast<
void> (0) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Failed to maintain validity of domtree!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6740, __PRETTY_FUNCTION__));

return Changed;
6743}

6745bool SimplifyCFGOpt::run(BasicBlock *BB) {
assert((!RequireAndPreserveDomTree ||(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Original domtree is invalid?") ? static_cast<void> (0
) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Original domtree is invalid?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6749, __PRETTY_FUNCTION__))
        (DTU &&(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Original domtree is invalid?") ? static_cast<void> (0
) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Original domtree is invalid?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6749, __PRETTY_FUNCTION__))
         DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) &&(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Original domtree is invalid?") ? static_cast<void> (0
) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Original domtree is invalid?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6749, __PRETTY_FUNCTION__))
       "Original domtree is invalid?")(((!RequireAndPreserveDomTree || (DTU && DTU->getDomTree
().verify(DominatorTree::VerificationLevel::Full))) &&
 "Original domtree is invalid?") ? static_cast<void> (0
) : __assert_fail ("(!RequireAndPreserveDomTree || (DTU && DTU->getDomTree().verify(DominatorTree::VerificationLevel::Full))) && \"Original domtree is invalid?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp"
, 6749, __PRETTY_FUNCTION__));

bool Changed = false;

// Repeated simplify BB as long as resimplification is requested.
do {
  Resimplify = false;

  // Perform one round of simplifcation. Resimplify flag will be set if
  // another iteration is requested.
  Changed |= simplifyOnce(BB);
} while (Resimplify);

return Changed;
6763}

6765bool llvm::simplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
                     DomTreeUpdater *DTU, const SimplifyCFGOptions &Options,
                     SmallPtrSetImpl<BasicBlock *> *LoopHeaders) {
return SimplifyCFGOpt(TTI, RequireAndPreserveDomTree ? DTU : nullptr,
                      BB->getModule()->getDataLayout(), LoopHeaders, Options)
    .run(BB);
6771}

←

/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h

→

1//===- llvm/Instructions.h - Instruction subclass definitions ---*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file exposes the class definitions of all of the subclasses of the
10// Instruction class.  This is meant to be an easy way to get access to all
11// instruction subclasses.
12//
13//===----------------------------------------------------------------------===//

15#ifndef LLVM_IR_INSTRUCTIONS_H
16#define LLVM_IR_INSTRUCTIONS_H

18#include "llvm/ADT/ArrayRef.h"
19#include "llvm/ADT/Bitfields.h"
20#include "llvm/ADT/None.h"
21#include "llvm/ADT/STLExtras.h"
22#include "llvm/ADT/SmallVector.h"
23#include "llvm/ADT/StringRef.h"
24#include "llvm/ADT/Twine.h"
25#include "llvm/ADT/iterator.h"
26#include "llvm/ADT/iterator_range.h"
27#include "llvm/IR/Attributes.h"
28#include "llvm/IR/BasicBlock.h"
29#include "llvm/IR/CallingConv.h"
30#include "llvm/IR/CFG.h"
31#include "llvm/IR/Constant.h"
32#include "llvm/IR/DerivedTypes.h"
33#include "llvm/IR/Function.h"
34#include "llvm/IR/InstrTypes.h"
35#include "llvm/IR/Instruction.h"
36#include "llvm/IR/OperandTraits.h"
37#include "llvm/IR/Type.h"
38#include "llvm/IR/Use.h"
39#include "llvm/IR/User.h"
40#include "llvm/IR/Value.h"
41#include "llvm/Support/AtomicOrdering.h"
42#include "llvm/Support/Casting.h"
43#include "llvm/Support/ErrorHandling.h"
44#include <cassert>
45#include <cstddef>
46#include <cstdint>
47#include <iterator>

49namespace llvm {

51class APInt;
52class ConstantInt;
53class DataLayout;
54class LLVMContext;

56//===----------------------------------------------------------------------===//
57//                                AllocaInst Class
58//===----------------------------------------------------------------------===//

60/// an instruction to allocate memory on the stack
61class AllocaInst : public UnaryInstruction {
Type *AllocatedType;

using AlignmentField = AlignmentBitfieldElementT<0>;
using UsedWithInAllocaField = BoolBitfieldElementT<AlignmentField::NextBit>;
using SwiftErrorField = BoolBitfieldElementT<UsedWithInAllocaField::NextBit>;
static_assert(Bitfield::areContiguous<AlignmentField, UsedWithInAllocaField,
                                      SwiftErrorField>(),
              "Bitfields must be contiguous");

71protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

AllocaInst *cloneImpl() const;

77public:
explicit AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize,
                    const Twine &Name, Instruction *InsertBefore);
AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize,
           const Twine &Name, BasicBlock *InsertAtEnd);

AllocaInst(Type *Ty, unsigned AddrSpace, const Twine &Name,
           Instruction *InsertBefore);
AllocaInst(Type *Ty, unsigned AddrSpace,
           const Twine &Name, BasicBlock *InsertAtEnd);

AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize, Align Align,
           const Twine &Name = "", Instruction *InsertBefore = nullptr);
AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize, Align Align,
           const Twine &Name, BasicBlock *InsertAtEnd);

/// Return true if there is an allocation size parameter to the allocation
/// instruction that is not 1.
bool isArrayAllocation() const;

/// Get the number of elements allocated. For a simple allocation of a single
/// element, this will return a constant 1 value.
const Value *getArraySize() const { return getOperand(0); }
Value *getArraySize() { return getOperand(0); }

/// Overload to return most specific pointer type.
PointerType *getType() const {
  return cast<PointerType>(Instruction::getType());
}

/// Get allocation size in bits. Returns None if size can't be determined,
/// e.g. in case of a VLA.
Optional<TypeSize> getAllocationSizeInBits(const DataLayout &DL) const;

/// Return the type that is being allocated by the instruction.
Type *getAllocatedType() const { return AllocatedType; }
/// for use only in special circumstances that need to generically
/// transform a whole instruction (eg: IR linking and vectorization).
void setAllocatedType(Type *Ty) { AllocatedType = Ty; }

/// Return the alignment of the memory that is being allocated by the
/// instruction.
Align getAlign() const {
  return Align(1ULL << getSubclassData<AlignmentField>());
}

void setAlignment(Align Align) {
  setSubclassData<AlignmentField>(Log2(Align));
}

// FIXME: Remove this one transition to Align is over.
unsigned getAlignment() const { return getAlign().value(); }

/// Return true if this alloca is in the entry block of the function and is a
/// constant size. If so, the code generator will fold it into the
/// prolog/epilog code, so it is basically free.
bool isStaticAlloca() const;

/// Return true if this alloca is used as an inalloca argument to a call. Such
/// allocas are never considered static even if they are in the entry block.
bool isUsedWithInAlloca() const {
  return getSubclassData<UsedWithInAllocaField>();
}

/// Specify whether this alloca is used to represent the arguments to a call.
void setUsedWithInAlloca(bool V) {
  setSubclassData<UsedWithInAllocaField>(V);
}

/// Return true if this alloca is used as a swifterror argument to a call.
bool isSwiftError() const { return getSubclassData<SwiftErrorField>(); }
/// Specify whether this alloca is used to represent a swifterror.
void setSwiftError(bool V) { setSubclassData<SwiftErrorField>(V); }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::Alloca);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

159private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}
166};

168//===----------------------------------------------------------------------===//
169//                                LoadInst Class
170//===----------------------------------------------------------------------===//

172/// An instruction for reading from memory. This uses the SubclassData field in
173/// Value to store whether or not the load is volatile.
174class LoadInst : public UnaryInstruction {
using VolatileField = BoolBitfieldElementT<0>;
using AlignmentField = AlignmentBitfieldElementT<VolatileField::NextBit>;
using OrderingField = AtomicOrderingBitfieldElementT<AlignmentField::NextBit>;
static_assert(
    Bitfield::areContiguous<VolatileField, AlignmentField, OrderingField>(),
    "Bitfields must be contiguous");

void AssertOK();

184protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

LoadInst *cloneImpl() const;

190public:
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr,
         Instruction *InsertBefore);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, BasicBlock *InsertAtEnd);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
         Instruction *InsertBefore);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
         BasicBlock *InsertAtEnd);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
         Align Align, Instruction *InsertBefore = nullptr);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
         Align Align, BasicBlock *InsertAtEnd);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
         Align Align, AtomicOrdering Order,
         SyncScope::ID SSID = SyncScope::System,
         Instruction *InsertBefore = nullptr);
LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
         Align Align, AtomicOrdering Order, SyncScope::ID SSID,
         BasicBlock *InsertAtEnd);

/// Return true if this is a load from a volatile memory location.
bool isVolatile() const { return getSubclassData<VolatileField>(); }

/// Specify whether this is a volatile load or not.
void setVolatile(bool V) { setSubclassData<VolatileField>(V); }

/// Return the alignment of the access that is being performed.
/// FIXME: Remove this function once transition to Align is over.
/// Use getAlign() instead.
unsigned getAlignment() const { return getAlign().value(); }

/// Return the alignment of the access that is being performed.
Align getAlign() const {
  return Align(1ULL << (getSubclassData<AlignmentField>()));
}

void setAlignment(Align Align) {
  setSubclassData<AlignmentField>(Log2(Align));
}

/// Returns the ordering constraint of this load instruction.
AtomicOrdering getOrdering() const {
  return getSubclassData<OrderingField>();
}
/// Sets the ordering constraint of this load instruction.  May not be Release
/// or AcquireRelease.
void setOrdering(AtomicOrdering Ordering) {
  setSubclassData<OrderingField>(Ordering);
}

/// Returns the synchronization scope ID of this load instruction.
SyncScope::ID getSyncScopeID() const {
  return SSID;
}

/// Sets the synchronization scope ID of this load instruction.
void setSyncScopeID(SyncScope::ID SSID) {
  this->SSID = SSID;
}

/// Sets the ordering constraint and the synchronization scope ID of this load
/// instruction.
void setAtomic(AtomicOrdering Ordering,
               SyncScope::ID SSID = SyncScope::System) {
  setOrdering(Ordering);
  setSyncScopeID(SSID);
}

bool isSimple() const { return !isAtomic() && !isVolatile(); }

bool isUnordered() const {
  return (getOrdering() == AtomicOrdering::NotAtomic ||
          getOrdering() == AtomicOrdering::Unordered) &&
         !isVolatile();
}

Value *getPointerOperand() { return getOperand(0); }
const Value *getPointerOperand() const { return getOperand(0); }
static unsigned getPointerOperandIndex() { return 0U; }
Type *getPointerOperandType() const { return getPointerOperand()->getType(); }

/// Returns the address space of the pointer operand.
unsigned getPointerAddressSpace() const {
  return getPointerOperandType()->getPointerAddressSpace();
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Load;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

284private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}

/// The synchronization scope ID of this load instruction.  Not quite enough
/// room in SubClassData for everything, so synchronization scope ID gets its
/// own field.
SyncScope::ID SSID;
296};

298//===----------------------------------------------------------------------===//
299//                                StoreInst Class
300//===----------------------------------------------------------------------===//

302/// An instruction for storing to memory.
303class StoreInst : public Instruction {
using VolatileField = BoolBitfieldElementT<0>;
using AlignmentField = AlignmentBitfieldElementT<VolatileField::NextBit>;
using OrderingField = AtomicOrderingBitfieldElementT<AlignmentField::NextBit>;
static_assert(
    Bitfield::areContiguous<VolatileField, AlignmentField, OrderingField>(),
    "Bitfields must be contiguous");

void AssertOK();

313protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

StoreInst *cloneImpl() const;

319public:
StoreInst(Value *Val, Value *Ptr, Instruction *InsertBefore);
StoreInst(Value *Val, Value *Ptr, BasicBlock *InsertAtEnd);
StoreInst(Value *Val, Value *Ptr, bool isVolatile, Instruction *InsertBefore);
StoreInst(Value *Val, Value *Ptr, bool isVolatile, BasicBlock *InsertAtEnd);
StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
          Instruction *InsertBefore = nullptr);
StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
          BasicBlock *InsertAtEnd);
StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
          AtomicOrdering Order, SyncScope::ID SSID = SyncScope::System,
          Instruction *InsertBefore = nullptr);
StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
          AtomicOrdering Order, SyncScope::ID SSID, BasicBlock *InsertAtEnd);

// allocate space for exactly two operands
void *operator new(size_t s) {
  return User::operator new(s, 2);
}

/// Return true if this is a store to a volatile memory location.
bool isVolatile() const { return getSubclassData<VolatileField>(); }

/// Specify whether this is a volatile store or not.
void setVolatile(bool V) { setSubclassData<VolatileField>(V); }

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Return the alignment of the access that is being performed
/// FIXME: Remove this function once transition to Align is over.
/// Use getAlign() instead.
unsigned getAlignment() const { return getAlign().value(); }

Align getAlign() const {
  return Align(1ULL << (getSubclassData<AlignmentField>()));
}

void setAlignment(Align Align) {
  setSubclassData<AlignmentField>(Log2(Align));
}

/// Returns the ordering constraint of this store instruction.
AtomicOrdering getOrdering() const {
  return getSubclassData<OrderingField>();
}

/// Sets the ordering constraint of this store instruction.  May not be
/// Acquire or AcquireRelease.
void setOrdering(AtomicOrdering Ordering) {
  setSubclassData<OrderingField>(Ordering);
}

/// Returns the synchronization scope ID of this store instruction.
SyncScope::ID getSyncScopeID() const {
  return SSID;
}

/// Sets the synchronization scope ID of this store instruction.
void setSyncScopeID(SyncScope::ID SSID) {
  this->SSID = SSID;
}

/// Sets the ordering constraint and the synchronization scope ID of this
/// store instruction.
void setAtomic(AtomicOrdering Ordering,
               SyncScope::ID SSID = SyncScope::System) {
  setOrdering(Ordering);
  setSyncScopeID(SSID);
}

bool isSimple() const { return !isAtomic() && !isVolatile(); }

bool isUnordered() const {
  return (getOrdering() == AtomicOrdering::NotAtomic ||
          getOrdering() == AtomicOrdering::Unordered) &&
         !isVolatile();
}

Value *getValueOperand() { return getOperand(0); }
const Value *getValueOperand() const { return getOperand(0); }

Value *getPointerOperand() { return getOperand(1); }
const Value *getPointerOperand() const { return getOperand(1); }
static unsigned getPointerOperandIndex() { return 1U; }
Type *getPointerOperandType() const { return getPointerOperand()->getType(); }

/// Returns the address space of the pointer operand.
unsigned getPointerAddressSpace() const {
  return getPointerOperandType()->getPointerAddressSpace();
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Store;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

419private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}

/// The synchronization scope ID of this store instruction.  Not quite enough
/// room in SubClassData for everything, so synchronization scope ID gets its
/// own field.
SyncScope::ID SSID;
431};

433template <>
434struct OperandTraits<StoreInst> : public FixedNumOperandTraits<StoreInst, 2> {
435};

437DEFINE_TRANSPARENT_OPERAND_ACCESSORS(StoreInst, Value)StoreInst::op_iterator StoreInst::op_begin() { return OperandTraits
<StoreInst>::op_begin(this); } StoreInst::const_op_iterator
 StoreInst::op_begin() const { return OperandTraits<StoreInst
>::op_begin(const_cast<StoreInst*>(this)); } StoreInst
::op_iterator StoreInst::op_end() { return OperandTraits<StoreInst
>::op_end(this); } StoreInst::const_op_iterator StoreInst::
op_end() const { return OperandTraits<StoreInst>::op_end
(const_cast<StoreInst*>(this)); } Value *StoreInst::getOperand
(unsigned i_nocapture) const { ((i_nocapture < OperandTraits
<StoreInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<StoreInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 437, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<StoreInst>::op_begin(const_cast<StoreInst
*>(this))[i_nocapture].get()); } void StoreInst::setOperand
(unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<StoreInst>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<StoreInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 437, __PRETTY_FUNCTION__)); OperandTraits<StoreInst>::
op_begin(this)[i_nocapture] = Val_nocapture; } unsigned StoreInst
::getNumOperands() const { return OperandTraits<StoreInst>
::operands(this); } template <int Idx_nocapture> Use &
StoreInst::Op() { return this->OpFrom<Idx_nocapture>
(this); } template <int Idx_nocapture> const Use &StoreInst
::Op() const { return this->OpFrom<Idx_nocapture>(this
); }

439//===----------------------------------------------------------------------===//
440//                                FenceInst Class
441//===----------------------------------------------------------------------===//

443/// An instruction for ordering other memory operations.
444class FenceInst : public Instruction {
using OrderingField = AtomicOrderingBitfieldElementT<0>;

void Init(AtomicOrdering Ordering, SyncScope::ID SSID);

449protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

FenceInst *cloneImpl() const;

455public:
// Ordering may only be Acquire, Release, AcquireRelease, or
// SequentiallyConsistent.
FenceInst(LLVMContext &C, AtomicOrdering Ordering,
          SyncScope::ID SSID = SyncScope::System,
          Instruction *InsertBefore = nullptr);
FenceInst(LLVMContext &C, AtomicOrdering Ordering, SyncScope::ID SSID,
          BasicBlock *InsertAtEnd);

// allocate space for exactly zero operands
void *operator new(size_t s) {
  return User::operator new(s, 0);
}

/// Returns the ordering constraint of this fence instruction.
AtomicOrdering getOrdering() const {
  return getSubclassData<OrderingField>();
}

/// Sets the ordering constraint of this fence instruction.  May only be
/// Acquire, Release, AcquireRelease, or SequentiallyConsistent.
void setOrdering(AtomicOrdering Ordering) {
  setSubclassData<OrderingField>(Ordering);
}

/// Returns the synchronization scope ID of this fence instruction.
SyncScope::ID getSyncScopeID() const {
  return SSID;
}

/// Sets the synchronization scope ID of this fence instruction.
void setSyncScopeID(SyncScope::ID SSID) {
  this->SSID = SSID;
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Fence;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

498private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}

/// The synchronization scope ID of this fence instruction.  Not quite enough
/// room in SubClassData for everything, so synchronization scope ID gets its
/// own field.
SyncScope::ID SSID;
510};

512//===----------------------------------------------------------------------===//
513//                                AtomicCmpXchgInst Class
514//===----------------------------------------------------------------------===//

516/// An instruction that atomically checks whether a
517/// specified value is in a memory location, and, if it is, stores a new value
518/// there. The value returned by this instruction is a pair containing the
519/// original value as first element, and an i1 indicating success (true) or
520/// failure (false) as second element.
521///
522class AtomicCmpXchgInst : public Instruction {
void Init(Value *Ptr, Value *Cmp, Value *NewVal, Align Align,
          AtomicOrdering SuccessOrdering, AtomicOrdering FailureOrdering,
          SyncScope::ID SSID);

template <unsigned Offset>
using AtomicOrderingBitfieldElement =
    typename Bitfield::Element<AtomicOrdering, Offset, 3,
                               AtomicOrdering::LAST>;

532protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

AtomicCmpXchgInst *cloneImpl() const;

538public:
AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
                  AtomicOrdering SuccessOrdering,
                  AtomicOrdering FailureOrdering, SyncScope::ID SSID,
                  Instruction *InsertBefore = nullptr);
AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
                  AtomicOrdering SuccessOrdering,
                  AtomicOrdering FailureOrdering, SyncScope::ID SSID,
                  BasicBlock *InsertAtEnd);

// allocate space for exactly three operands
void *operator new(size_t s) {
  return User::operator new(s, 3);
}

using VolatileField = BoolBitfieldElementT<0>;
using WeakField = BoolBitfieldElementT<VolatileField::NextBit>;
using SuccessOrderingField =
    AtomicOrderingBitfieldElementT<WeakField::NextBit>;
using FailureOrderingField =
    AtomicOrderingBitfieldElementT<SuccessOrderingField::NextBit>;
using AlignmentField =
    AlignmentBitfieldElementT<FailureOrderingField::NextBit>;
static_assert(
    Bitfield::areContiguous<VolatileField, WeakField, SuccessOrderingField,
                            FailureOrderingField, AlignmentField>(),
    "Bitfields must be contiguous");

/// Return the alignment of the memory that is being allocated by the
/// instruction.
Align getAlign() const {
  return Align(1ULL << getSubclassData<AlignmentField>());
}

void setAlignment(Align Align) {
  setSubclassData<AlignmentField>(Log2(Align));
}

/// Return true if this is a cmpxchg from a volatile memory
/// location.
///
bool isVolatile() const { return getSubclassData<VolatileField>(); }

/// Specify whether this is a volatile cmpxchg.
///
void setVolatile(bool V) { setSubclassData<VolatileField>(V); }

/// Return true if this cmpxchg may spuriously fail.
bool isWeak() const { return getSubclassData<WeakField>(); }

void setWeak(bool IsWeak) { setSubclassData<WeakField>(IsWeak); }

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Returns the success ordering constraint of this cmpxchg instruction.
AtomicOrdering getSuccessOrdering() const {
  return getSubclassData<SuccessOrderingField>();
}

/// Sets the success ordering constraint of this cmpxchg instruction.
void setSuccessOrdering(AtomicOrdering Ordering) {
  assert(Ordering != AtomicOrdering::NotAtomic &&((Ordering != AtomicOrdering::NotAtomic && "CmpXchg instructions can only be atomic."
) ? static_cast<void> (0) : __assert_fail ("Ordering != AtomicOrdering::NotAtomic && \"CmpXchg instructions can only be atomic.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 601, __PRETTY_FUNCTION__))
         "CmpXchg instructions can only be atomic.")((Ordering != AtomicOrdering::NotAtomic && "CmpXchg instructions can only be atomic."
) ? static_cast<void> (0) : __assert_fail ("Ordering != AtomicOrdering::NotAtomic && \"CmpXchg instructions can only be atomic.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 601, __PRETTY_FUNCTION__));
  setSubclassData<SuccessOrderingField>(Ordering);
}

/// Returns the failure ordering constraint of this cmpxchg instruction.
AtomicOrdering getFailureOrdering() const {
  return getSubclassData<FailureOrderingField>();
}

/// Sets the failure ordering constraint of this cmpxchg instruction.
void setFailureOrdering(AtomicOrdering Ordering) {
  assert(Ordering != AtomicOrdering::NotAtomic &&((Ordering != AtomicOrdering::NotAtomic && "CmpXchg instructions can only be atomic."
) ? static_cast<void> (0) : __assert_fail ("Ordering != AtomicOrdering::NotAtomic && \"CmpXchg instructions can only be atomic.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 613, __PRETTY_FUNCTION__))
         "CmpXchg instructions can only be atomic.")((Ordering != AtomicOrdering::NotAtomic && "CmpXchg instructions can only be atomic."
) ? static_cast<void> (0) : __assert_fail ("Ordering != AtomicOrdering::NotAtomic && \"CmpXchg instructions can only be atomic.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 613, __PRETTY_FUNCTION__));
  setSubclassData<FailureOrderingField>(Ordering);
}

/// Returns the synchronization scope ID of this cmpxchg instruction.
SyncScope::ID getSyncScopeID() const {
  return SSID;
}

/// Sets the synchronization scope ID of this cmpxchg instruction.
void setSyncScopeID(SyncScope::ID SSID) {
  this->SSID = SSID;
}

Value *getPointerOperand() { return getOperand(0); }
const Value *getPointerOperand() const { return getOperand(0); }
static unsigned getPointerOperandIndex() { return 0U; }

Value *getCompareOperand() { return getOperand(1); }
const Value *getCompareOperand() const { return getOperand(1); }

Value *getNewValOperand() { return getOperand(2); }
const Value *getNewValOperand() const { return getOperand(2); }

/// Returns the address space of the pointer operand.
unsigned getPointerAddressSpace() const {
  return getPointerOperand()->getType()->getPointerAddressSpace();
}

/// Returns the strongest permitted ordering on failure, given the
/// desired ordering on success.
///
/// If the comparison in a cmpxchg operation fails, there is no atomic store
/// so release semantics cannot be provided. So this function drops explicit
/// Release requests from the AtomicOrdering. A SequentiallyConsistent
/// operation would remain SequentiallyConsistent.
static AtomicOrdering
getStrongestFailureOrdering(AtomicOrdering SuccessOrdering) {
  switch (SuccessOrdering) {
  default:
    llvm_unreachable("invalid cmpxchg success ordering")::llvm::llvm_unreachable_internal("invalid cmpxchg success ordering"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 653);
  case AtomicOrdering::Release:
  case AtomicOrdering::Monotonic:
    return AtomicOrdering::Monotonic;
  case AtomicOrdering::AcquireRelease:
  case AtomicOrdering::Acquire:
    return AtomicOrdering::Acquire;
  case AtomicOrdering::SequentiallyConsistent:
    return AtomicOrdering::SequentiallyConsistent;
  }
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::AtomicCmpXchg;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

673private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}

/// The synchronization scope ID of this cmpxchg instruction.  Not quite
/// enough room in SubClassData for everything, so synchronization scope ID
/// gets its own field.
SyncScope::ID SSID;
685};

687template <>
688struct OperandTraits<AtomicCmpXchgInst> :
  public FixedNumOperandTraits<AtomicCmpXchgInst, 3> {
690};

692DEFINE_TRANSPARENT_OPERAND_ACCESSORS(AtomicCmpXchgInst, Value)AtomicCmpXchgInst::op_iterator AtomicCmpXchgInst::op_begin() {
 return OperandTraits<AtomicCmpXchgInst>::op_begin(this
); } AtomicCmpXchgInst::const_op_iterator AtomicCmpXchgInst::
op_begin() const { return OperandTraits<AtomicCmpXchgInst>
::op_begin(const_cast<AtomicCmpXchgInst*>(this)); } AtomicCmpXchgInst
::op_iterator AtomicCmpXchgInst::op_end() { return OperandTraits
<AtomicCmpXchgInst>::op_end(this); } AtomicCmpXchgInst::
const_op_iterator AtomicCmpXchgInst::op_end() const { return OperandTraits
<AtomicCmpXchgInst>::op_end(const_cast<AtomicCmpXchgInst
*>(this)); } Value *AtomicCmpXchgInst::getOperand(unsigned
 i_nocapture) const { ((i_nocapture < OperandTraits<AtomicCmpXchgInst
>::operands(this) && "getOperand() out of range!")
 ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<AtomicCmpXchgInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 692, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<AtomicCmpXchgInst>::op_begin(const_cast
<AtomicCmpXchgInst*>(this))[i_nocapture].get()); } void
 AtomicCmpXchgInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((i_nocapture < OperandTraits<AtomicCmpXchgInst>
::operands(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<AtomicCmpXchgInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 692, __PRETTY_FUNCTION__)); OperandTraits<AtomicCmpXchgInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 AtomicCmpXchgInst::getNumOperands() const { return OperandTraits
<AtomicCmpXchgInst>::operands(this); } template <int
 Idx_nocapture> Use &AtomicCmpXchgInst::Op() { return this
->OpFrom<Idx_nocapture>(this); } template <int Idx_nocapture
> const Use &AtomicCmpXchgInst::Op() const { return this
->OpFrom<Idx_nocapture>(this); }

694//===----------------------------------------------------------------------===//
695//                                AtomicRMWInst Class
696//===----------------------------------------------------------------------===//

698/// an instruction that atomically reads a memory location,
699/// combines it with another value, and then stores the result back.  Returns
700/// the old value.
701///
702class AtomicRMWInst : public Instruction {
703protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

AtomicRMWInst *cloneImpl() const;

709public:
/// This enumeration lists the possible modifications atomicrmw can make.  In
/// the descriptions, 'p' is the pointer to the instruction's memory location,
/// 'old' is the initial value of *p, and 'v' is the other value passed to the
/// instruction.  These instructions always return 'old'.
enum BinOp : unsigned {
  /// *p = v
  Xchg,
  /// *p = old + v
  Add,
  /// *p = old - v
  Sub,
  /// *p = old & v
  And,
  /// *p = ~(old & v)
  Nand,
  /// *p = old | v
  Or,
  /// *p = old ^ v
  Xor,
  /// *p = old >signed v ? old : v
  Max,
  /// *p = old <signed v ? old : v
  Min,
  /// *p = old >unsigned v ? old : v
  UMax,
  /// *p = old <unsigned v ? old : v
  UMin,

  /// *p = old + v
  FAdd,

  /// *p = old - v
  FSub,

  FIRST_BINOP = Xchg,
  LAST_BINOP = FSub,
  BAD_BINOP
};

749private:
template <unsigned Offset>
using AtomicOrderingBitfieldElement =
    typename Bitfield::Element<AtomicOrdering, Offset, 3,
                               AtomicOrdering::LAST>;

template <unsigned Offset>
using BinOpBitfieldElement =
    typename Bitfield::Element<BinOp, Offset, 4, BinOp::LAST_BINOP>;

759public:
AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
              AtomicOrdering Ordering, SyncScope::ID SSID,
              Instruction *InsertBefore = nullptr);
AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
              AtomicOrdering Ordering, SyncScope::ID SSID,
              BasicBlock *InsertAtEnd);

// allocate space for exactly two operands
void *operator new(size_t s) {
  return User::operator new(s, 2);
}

using VolatileField = BoolBitfieldElementT<0>;
using AtomicOrderingField =
    AtomicOrderingBitfieldElementT<VolatileField::NextBit>;
using OperationField = BinOpBitfieldElement<AtomicOrderingField::NextBit>;
using AlignmentField = AlignmentBitfieldElementT<OperationField::NextBit>;
static_assert(Bitfield::areContiguous<VolatileField, AtomicOrderingField,
                                      OperationField, AlignmentField>(),
              "Bitfields must be contiguous");

BinOp getOperation() const { return getSubclassData<OperationField>(); }

static StringRef getOperationName(BinOp Op);

static bool isFPOperation(BinOp Op) {
  switch (Op) {
  case AtomicRMWInst::FAdd:
  case AtomicRMWInst::FSub:
    return true;
  default:
    return false;
  }
}

void setOperation(BinOp Operation) {
  setSubclassData<OperationField>(Operation);
}

/// Return the alignment of the memory that is being allocated by the
/// instruction.
Align getAlign() const {
  return Align(1ULL << getSubclassData<AlignmentField>());
}

void setAlignment(Align Align) {
  setSubclassData<AlignmentField>(Log2(Align));
}

/// Return true if this is a RMW on a volatile memory location.
///
bool isVolatile() const { return getSubclassData<VolatileField>(); }

/// Specify whether this is a volatile RMW or not.
///
void setVolatile(bool V) { setSubclassData<VolatileField>(V); }

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Returns the ordering constraint of this rmw instruction.
AtomicOrdering getOrdering() const {
  return getSubclassData<AtomicOrderingField>();
}

/// Sets the ordering constraint of this rmw instruction.
void setOrdering(AtomicOrdering Ordering) {
  assert(Ordering != AtomicOrdering::NotAtomic &&((Ordering != AtomicOrdering::NotAtomic && "atomicrmw instructions can only be atomic."
) ? static_cast<void> (0) : __assert_fail ("Ordering != AtomicOrdering::NotAtomic && \"atomicrmw instructions can only be atomic.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 828, __PRETTY_FUNCTION__))
         "atomicrmw instructions can only be atomic.")((Ordering != AtomicOrdering::NotAtomic && "atomicrmw instructions can only be atomic."
) ? static_cast<void> (0) : __assert_fail ("Ordering != AtomicOrdering::NotAtomic && \"atomicrmw instructions can only be atomic.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 828, __PRETTY_FUNCTION__));
  setSubclassData<AtomicOrderingField>(Ordering);
}

/// Returns the synchronization scope ID of this rmw instruction.
SyncScope::ID getSyncScopeID() const {
  return SSID;
}

/// Sets the synchronization scope ID of this rmw instruction.
void setSyncScopeID(SyncScope::ID SSID) {
  this->SSID = SSID;
}

Value *getPointerOperand() { return getOperand(0); }
const Value *getPointerOperand() const { return getOperand(0); }
static unsigned getPointerOperandIndex() { return 0U; }

Value *getValOperand() { return getOperand(1); }
const Value *getValOperand() const { return getOperand(1); }

/// Returns the address space of the pointer operand.
unsigned getPointerAddressSpace() const {
  return getPointerOperand()->getType()->getPointerAddressSpace();
}

bool isFloatingPointOperation() const {
  return isFPOperation(getOperation());
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::AtomicRMW;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

866private:
void Init(BinOp Operation, Value *Ptr, Value *Val, Align Align,
          AtomicOrdering Ordering, SyncScope::ID SSID);

// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}

/// The synchronization scope ID of this rmw instruction.  Not quite enough
/// room in SubClassData for everything, so synchronization scope ID gets its
/// own field.
SyncScope::ID SSID;
881};

883template <>
884struct OperandTraits<AtomicRMWInst>
  : public FixedNumOperandTraits<AtomicRMWInst,2> {
886};

888DEFINE_TRANSPARENT_OPERAND_ACCESSORS(AtomicRMWInst, Value)AtomicRMWInst::op_iterator AtomicRMWInst::op_begin() { return
 OperandTraits<AtomicRMWInst>::op_begin(this); } AtomicRMWInst
::const_op_iterator AtomicRMWInst::op_begin() const { return OperandTraits
<AtomicRMWInst>::op_begin(const_cast<AtomicRMWInst*>
(this)); } AtomicRMWInst::op_iterator AtomicRMWInst::op_end()
 { return OperandTraits<AtomicRMWInst>::op_end(this); }
 AtomicRMWInst::const_op_iterator AtomicRMWInst::op_end() const
 { return OperandTraits<AtomicRMWInst>::op_end(const_cast
<AtomicRMWInst*>(this)); } Value *AtomicRMWInst::getOperand
(unsigned i_nocapture) const { ((i_nocapture < OperandTraits
<AtomicRMWInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<AtomicRMWInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 888, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<AtomicRMWInst>::op_begin(const_cast<
AtomicRMWInst*>(this))[i_nocapture].get()); } void AtomicRMWInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
i_nocapture < OperandTraits<AtomicRMWInst>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<AtomicRMWInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 888, __PRETTY_FUNCTION__)); OperandTraits<AtomicRMWInst>
::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned AtomicRMWInst
::getNumOperands() const { return OperandTraits<AtomicRMWInst
>::operands(this); } template <int Idx_nocapture> Use
 &AtomicRMWInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
AtomicRMWInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }

890//===----------------------------------------------------------------------===//
891//                             GetElementPtrInst Class
892//===----------------------------------------------------------------------===//

894// checkGEPType - Simple wrapper function to give a better assertion failure
895// message on bad indexes for a gep instruction.
896//
897inline Type *checkGEPType(Type *Ty) {
assert(Ty && "Invalid GetElementPtrInst indices for type!")((Ty && "Invalid GetElementPtrInst indices for type!"
) ? static_cast<void> (0) : __assert_fail ("Ty && \"Invalid GetElementPtrInst indices for type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 898, __PRETTY_FUNCTION__));
return Ty;
900}

902/// an instruction for type-safe pointer arithmetic to
903/// access elements of arrays and structs
904///
905class GetElementPtrInst : public Instruction {
Type *SourceElementType;
Type *ResultElementType;

GetElementPtrInst(const GetElementPtrInst &GEPI);

/// Constructors - Create a getelementptr instruction with a base pointer an
/// list of indices. The first ctor can optionally insert before an existing
/// instruction, the second appends the new instruction to the specified
/// BasicBlock.
inline GetElementPtrInst(Type *PointeeType, Value *Ptr,
                         ArrayRef<Value *> IdxList, unsigned Values,
                         const Twine &NameStr, Instruction *InsertBefore);
inline GetElementPtrInst(Type *PointeeType, Value *Ptr,
                         ArrayRef<Value *> IdxList, unsigned Values,
                         const Twine &NameStr, BasicBlock *InsertAtEnd);

void init(Value *Ptr, ArrayRef<Value *> IdxList, const Twine &NameStr);

924protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

GetElementPtrInst *cloneImpl() const;

930public:
static GetElementPtrInst *Create(Type *PointeeType, Value *Ptr,
                                 ArrayRef<Value *> IdxList,
                                 const Twine &NameStr = "",
                                 Instruction *InsertBefore = nullptr) {
  unsigned Values = 1 + unsigned(IdxList.size());
  if (!PointeeType)
    PointeeType =
        cast<PointerType>(Ptr->getType()->getScalarType())->getElementType();
  else
    assert(((PointeeType == cast<PointerType>(Ptr->getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("PointeeType == cast<PointerType>(Ptr->getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 942, __PRETTY_FUNCTION__))
        PointeeType ==((PointeeType == cast<PointerType>(Ptr->getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("PointeeType == cast<PointerType>(Ptr->getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 942, __PRETTY_FUNCTION__))
        cast<PointerType>(Ptr->getType()->getScalarType())->getElementType())((PointeeType == cast<PointerType>(Ptr->getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("PointeeType == cast<PointerType>(Ptr->getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 942, __PRETTY_FUNCTION__));
  return new (Values) GetElementPtrInst(PointeeType, Ptr, IdxList, Values,
                                        NameStr, InsertBefore);
}

static GetElementPtrInst *Create(Type *PointeeType, Value *Ptr,
                                 ArrayRef<Value *> IdxList,
                                 const Twine &NameStr,
                                 BasicBlock *InsertAtEnd) {
  unsigned Values = 1 + unsigned(IdxList.size());
  if (!PointeeType)
    PointeeType =
        cast<PointerType>(Ptr->getType()->getScalarType())->getElementType();
  else
    assert(((PointeeType == cast<PointerType>(Ptr->getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("PointeeType == cast<PointerType>(Ptr->getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 958, __PRETTY_FUNCTION__))
        PointeeType ==((PointeeType == cast<PointerType>(Ptr->getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("PointeeType == cast<PointerType>(Ptr->getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 958, __PRETTY_FUNCTION__))
        cast<PointerType>(Ptr->getType()->getScalarType())->getElementType())((PointeeType == cast<PointerType>(Ptr->getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("PointeeType == cast<PointerType>(Ptr->getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 958, __PRETTY_FUNCTION__));
  return new (Values) GetElementPtrInst(PointeeType, Ptr, IdxList, Values,
                                        NameStr, InsertAtEnd);
}

/// Create an "inbounds" getelementptr. See the documentation for the
/// "inbounds" flag in LangRef.html for details.
static GetElementPtrInst *CreateInBounds(Value *Ptr,
                                         ArrayRef<Value *> IdxList,
                                         const Twine &NameStr = "",
                                         Instruction *InsertBefore = nullptr){
  return CreateInBounds(nullptr, Ptr, IdxList, NameStr, InsertBefore);
}

static GetElementPtrInst *
CreateInBounds(Type *PointeeType, Value *Ptr, ArrayRef<Value *> IdxList,
               const Twine &NameStr = "",
               Instruction *InsertBefore = nullptr) {
  GetElementPtrInst *GEP =
      Create(PointeeType, Ptr, IdxList, NameStr, InsertBefore);
  GEP->setIsInBounds(true);
  return GEP;
}

static GetElementPtrInst *CreateInBounds(Value *Ptr,
                                         ArrayRef<Value *> IdxList,
                                         const Twine &NameStr,
                                         BasicBlock *InsertAtEnd) {
  return CreateInBounds(nullptr, Ptr, IdxList, NameStr, InsertAtEnd);
}

static GetElementPtrInst *CreateInBounds(Type *PointeeType, Value *Ptr,
                                         ArrayRef<Value *> IdxList,
                                         const Twine &NameStr,
                                         BasicBlock *InsertAtEnd) {
  GetElementPtrInst *GEP =
      Create(PointeeType, Ptr, IdxList, NameStr, InsertAtEnd);
  GEP->setIsInBounds(true);
  return GEP;
}

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

Type *getSourceElementType() const { return SourceElementType; }

void setSourceElementType(Type *Ty) { SourceElementType = Ty; }
void setResultElementType(Type *Ty) { ResultElementType = Ty; }

Type *getResultElementType() const {
  assert(ResultElementType ==((ResultElementType == cast<PointerType>(getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("ResultElementType == cast<PointerType>(getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1009, __PRETTY_FUNCTION__))
         cast<PointerType>(getType()->getScalarType())->getElementType())((ResultElementType == cast<PointerType>(getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("ResultElementType == cast<PointerType>(getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1009, __PRETTY_FUNCTION__));
  return ResultElementType;
}

/// Returns the address space of this instruction's pointer type.
unsigned getAddressSpace() const {
  // Note that this is always the same as the pointer operand's address space
  // and that is cheaper to compute, so cheat here.
  return getPointerAddressSpace();
}

/// Returns the result type of a getelementptr with the given source
/// element type and indexes.
///
/// Null is returned if the indices are invalid for the specified
/// source element type.
static Type *getIndexedType(Type *Ty, ArrayRef<Value *> IdxList);
static Type *getIndexedType(Type *Ty, ArrayRef<Constant *> IdxList);
static Type *getIndexedType(Type *Ty, ArrayRef<uint64_t> IdxList);

/// Return the type of the element at the given index of an indexable
/// type.  This is equivalent to "getIndexedType(Agg, {Zero, Idx})".
///
/// Returns null if the type can't be indexed, or the given index is not
/// legal for the given type.
static Type *getTypeAtIndex(Type *Ty, Value *Idx);
static Type *getTypeAtIndex(Type *Ty, uint64_t Idx);

inline op_iterator       idx_begin()       { return op_begin()+1; }
inline const_op_iterator idx_begin() const { return op_begin()+1; }
inline op_iterator       idx_end()         { return op_end(); }
inline const_op_iterator idx_end()   const { return op_end(); }

inline iterator_range<op_iterator> indices() {
  return make_range(idx_begin(), idx_end());
}

inline iterator_range<const_op_iterator> indices() const {
  return make_range(idx_begin(), idx_end());
}

Value *getPointerOperand() {
  return getOperand(0);
}
const Value *getPointerOperand() const {
  return getOperand(0);
}
static unsigned getPointerOperandIndex() {
  return 0U;    // get index for modifying correct operand.
}

/// Method to return the pointer operand as a
/// PointerType.
Type *getPointerOperandType() const {
  return getPointerOperand()->getType();
}

/// Returns the address space of the pointer operand.
unsigned getPointerAddressSpace() const {
  return getPointerOperandType()->getPointerAddressSpace();
}

/// Returns the pointer type returned by the GEP
/// instruction, which may be a vector of pointers.
static Type *getGEPReturnType(Type *ElTy, Value *Ptr,
                              ArrayRef<Value *> IdxList) {
  Type *PtrTy = PointerType::get(checkGEPType(getIndexedType(ElTy, IdxList)),
                                 Ptr->getType()->getPointerAddressSpace());
  // Vector GEP
  if (auto *PtrVTy = dyn_cast<VectorType>(Ptr->getType())) {
    ElementCount EltCount = PtrVTy->getElementCount();
    return VectorType::get(PtrTy, EltCount);
  }
  for (Value *Index : IdxList)
    if (auto *IndexVTy = dyn_cast<VectorType>(Index->getType())) {
      ElementCount EltCount = IndexVTy->getElementCount();
      return VectorType::get(PtrTy, EltCount);
    }
  // Scalar GEP
  return PtrTy;
}

unsigned getNumIndices() const {  // Note: always non-negative
  return getNumOperands() - 1;
}

bool hasIndices() const {
  return getNumOperands() > 1;
}

/// Return true if all of the indices of this GEP are
/// zeros.  If so, the result pointer and the first operand have the same
/// value, just potentially different types.
bool hasAllZeroIndices() const;

/// Return true if all of the indices of this GEP are
/// constant integers.  If so, the result pointer and the first operand have
/// a constant offset between them.
bool hasAllConstantIndices() const;

/// Set or clear the inbounds flag on this GEP instruction.
/// See LangRef.html for the meaning of inbounds on a getelementptr.
void setIsInBounds(bool b = true);

/// Determine whether the GEP has the inbounds flag.
bool isInBounds() const;

/// Accumulate the constant address offset of this GEP if possible.
///
/// This routine accepts an APInt into which it will accumulate the constant
/// offset of this GEP if the GEP is in fact constant. If the GEP is not
/// all-constant, it returns false and the value of the offset APInt is
/// undefined (it is *not* preserved!). The APInt passed into this routine
/// must be at least as wide as the IntPtr type for the address space of
/// the base GEP pointer.
bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const;

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::GetElementPtr);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1133};

1135template <>
1136struct OperandTraits<GetElementPtrInst> :
public VariadicOperandTraits<GetElementPtrInst, 1> {
1138};

1140GetElementPtrInst::GetElementPtrInst(Type *PointeeType, Value *Ptr,
                                   ArrayRef<Value *> IdxList, unsigned Values,
                                   const Twine &NameStr,
                                   Instruction *InsertBefore)
  : Instruction(getGEPReturnType(PointeeType, Ptr, IdxList), GetElementPtr,
                OperandTraits<GetElementPtrInst>::op_end(this) - Values,
                Values, InsertBefore),
    SourceElementType(PointeeType),
    ResultElementType(getIndexedType(PointeeType, IdxList)) {
assert(ResultElementType ==((ResultElementType == cast<PointerType>(getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("ResultElementType == cast<PointerType>(getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1150, __PRETTY_FUNCTION__))
       cast<PointerType>(getType()->getScalarType())->getElementType())((ResultElementType == cast<PointerType>(getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("ResultElementType == cast<PointerType>(getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1150, __PRETTY_FUNCTION__));
init(Ptr, IdxList, NameStr);
1152}

1154GetElementPtrInst::GetElementPtrInst(Type *PointeeType, Value *Ptr,
                                   ArrayRef<Value *> IdxList, unsigned Values,
                                   const Twine &NameStr,
                                   BasicBlock *InsertAtEnd)
  : Instruction(getGEPReturnType(PointeeType, Ptr, IdxList), GetElementPtr,
                OperandTraits<GetElementPtrInst>::op_end(this) - Values,
                Values, InsertAtEnd),
    SourceElementType(PointeeType),
    ResultElementType(getIndexedType(PointeeType, IdxList)) {
assert(ResultElementType ==((ResultElementType == cast<PointerType>(getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("ResultElementType == cast<PointerType>(getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1164, __PRETTY_FUNCTION__))
       cast<PointerType>(getType()->getScalarType())->getElementType())((ResultElementType == cast<PointerType>(getType()->
getScalarType())->getElementType()) ? static_cast<void>
 (0) : __assert_fail ("ResultElementType == cast<PointerType>(getType()->getScalarType())->getElementType()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1164, __PRETTY_FUNCTION__));
init(Ptr, IdxList, NameStr);
1166}

1168DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GetElementPtrInst, Value)GetElementPtrInst::op_iterator GetElementPtrInst::op_begin() {
 return OperandTraits<GetElementPtrInst>::op_begin(this
); } GetElementPtrInst::const_op_iterator GetElementPtrInst::
op_begin() const { return OperandTraits<GetElementPtrInst>
::op_begin(const_cast<GetElementPtrInst*>(this)); } GetElementPtrInst
::op_iterator GetElementPtrInst::op_end() { return OperandTraits
<GetElementPtrInst>::op_end(this); } GetElementPtrInst::
const_op_iterator GetElementPtrInst::op_end() const { return OperandTraits
<GetElementPtrInst>::op_end(const_cast<GetElementPtrInst
*>(this)); } Value *GetElementPtrInst::getOperand(unsigned
 i_nocapture) const { ((i_nocapture < OperandTraits<GetElementPtrInst
>::operands(this) && "getOperand() out of range!")
 ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<GetElementPtrInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1168, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<GetElementPtrInst>::op_begin(const_cast
<GetElementPtrInst*>(this))[i_nocapture].get()); } void
 GetElementPtrInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((i_nocapture < OperandTraits<GetElementPtrInst>
::operands(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<GetElementPtrInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1168, __PRETTY_FUNCTION__)); OperandTraits<GetElementPtrInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 GetElementPtrInst::getNumOperands() const { return OperandTraits
<GetElementPtrInst>::operands(this); } template <int
 Idx_nocapture> Use &GetElementPtrInst::Op() { return this
->OpFrom<Idx_nocapture>(this); } template <int Idx_nocapture
> const Use &GetElementPtrInst::Op() const { return this
->OpFrom<Idx_nocapture>(this); }

1170//===----------------------------------------------------------------------===//
1171//                               ICmpInst Class
1172//===----------------------------------------------------------------------===//

1174/// This instruction compares its operands according to the predicate given
1175/// to the constructor. It only operates on integers or pointers. The operands
1176/// must be identical types.
1177/// Represent an integer comparison operator.
1178class ICmpInst: public CmpInst {
void AssertOK() {
  assert(isIntPredicate() &&((isIntPredicate() && "Invalid ICmp predicate value")
 ? static_cast<void> (0) : __assert_fail ("isIntPredicate() && \"Invalid ICmp predicate value\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1181, __PRETTY_FUNCTION__))
         "Invalid ICmp predicate value")((isIntPredicate() && "Invalid ICmp predicate value")
 ? static_cast<void> (0) : __assert_fail ("isIntPredicate() && \"Invalid ICmp predicate value\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1181, __PRETTY_FUNCTION__));
  assert(getOperand(0)->getType() == getOperand(1)->getType() &&((getOperand(0)->getType() == getOperand(1)->getType() &&
 "Both operands to ICmp instruction are not of the same type!"
) ? static_cast<void> (0) : __assert_fail ("getOperand(0)->getType() == getOperand(1)->getType() && \"Both operands to ICmp instruction are not of the same type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1183, __PRETTY_FUNCTION__))
        "Both operands to ICmp instruction are not of the same type!")((getOperand(0)->getType() == getOperand(1)->getType() &&
 "Both operands to ICmp instruction are not of the same type!"
) ? static_cast<void> (0) : __assert_fail ("getOperand(0)->getType() == getOperand(1)->getType() && \"Both operands to ICmp instruction are not of the same type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1183, __PRETTY_FUNCTION__));
  // Check that the operands are the right type
  assert((getOperand(0)->getType()->isIntOrIntVectorTy() ||(((getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand
(0)->getType()->isPtrOrPtrVectorTy()) && "Invalid operand types for ICmp instruction"
) ? static_cast<void> (0) : __assert_fail ("(getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand(0)->getType()->isPtrOrPtrVectorTy()) && \"Invalid operand types for ICmp instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1187, __PRETTY_FUNCTION__))
          getOperand(0)->getType()->isPtrOrPtrVectorTy()) &&(((getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand
(0)->getType()->isPtrOrPtrVectorTy()) && "Invalid operand types for ICmp instruction"
) ? static_cast<void> (0) : __assert_fail ("(getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand(0)->getType()->isPtrOrPtrVectorTy()) && \"Invalid operand types for ICmp instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1187, __PRETTY_FUNCTION__))
         "Invalid operand types for ICmp instruction")(((getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand
(0)->getType()->isPtrOrPtrVectorTy()) && "Invalid operand types for ICmp instruction"
) ? static_cast<void> (0) : __assert_fail ("(getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand(0)->getType()->isPtrOrPtrVectorTy()) && \"Invalid operand types for ICmp instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1187, __PRETTY_FUNCTION__));
}

1190protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical ICmpInst
ICmpInst *cloneImpl() const;

1197public:
/// Constructor with insert-before-instruction semantics.
ICmpInst(
  Instruction *InsertBefore,  ///< Where to insert
  Predicate pred,  ///< The predicate to use for the comparison
  Value *LHS,      ///< The left-hand-side of the expression
  Value *RHS,      ///< The right-hand-side of the expression
  const Twine &NameStr = ""  ///< Name of the instruction
) : CmpInst(makeCmpResultType(LHS->getType()),
            Instruction::ICmp, pred, LHS, RHS, NameStr,
            InsertBefore) {
1208#ifndef NDEBUG
AssertOK();
1210#endif
}

/// Constructor with insert-at-end semantics.
ICmpInst(
  BasicBlock &InsertAtEnd, ///< Block to insert into.
  Predicate pred,  ///< The predicate to use for the comparison
  Value *LHS,      ///< The left-hand-side of the expression
  Value *RHS,      ///< The right-hand-side of the expression
  const Twine &NameStr = ""  ///< Name of the instruction
) : CmpInst(makeCmpResultType(LHS->getType()),
            Instruction::ICmp, pred, LHS, RHS, NameStr,
            &InsertAtEnd) {
1223#ifndef NDEBUG
AssertOK();
1225#endif
}

/// Constructor with no-insertion semantics
ICmpInst(
  Predicate pred, ///< The predicate to use for the comparison
  Value *LHS,     ///< The left-hand-side of the expression
  Value *RHS,     ///< The right-hand-side of the expression
  const Twine &NameStr = "" ///< Name of the instruction
) : CmpInst(makeCmpResultType(LHS->getType()),
            Instruction::ICmp, pred, LHS, RHS, NameStr) {
1236#ifndef NDEBUG
AssertOK();
1238#endif
}

/// For example, EQ->EQ, SLE->SLE, UGT->SGT, etc.
/// @returns the predicate that would be the result if the operand were
/// regarded as signed.
/// Return the signed version of the predicate
Predicate getSignedPredicate() const {
  return getSignedPredicate(getPredicate());
}

/// This is a static version that you can use without an instruction.
/// Return the signed version of the predicate.
static Predicate getSignedPredicate(Predicate pred);

/// For example, EQ->EQ, SLE->ULE, UGT->UGT, etc.
/// @returns the predicate that would be the result if the operand were
/// regarded as unsigned.
/// Return the unsigned version of the predicate
Predicate getUnsignedPredicate() const {
  return getUnsignedPredicate(getPredicate());
}

/// This is a static version that you can use without an instruction.
/// Return the unsigned version of the predicate.
static Predicate getUnsignedPredicate(Predicate pred);

/// Return true if this predicate is either EQ or NE.  This also
/// tests for commutativity.
static bool isEquality(Predicate P) {
  return P == ICMP_EQ || P == ICMP_NE;
}

/// Return true if this predicate is either EQ or NE.  This also
/// tests for commutativity.
bool isEquality() const {
  return isEquality(getPredicate());
}

/// @returns true if the predicate of this ICmpInst is commutative
/// Determine if this relation is commutative.
bool isCommutative() const { return isEquality(); }

/// Return true if the predicate is relational (not EQ or NE).
///
bool isRelational() const {
  return !isEquality();
}

/// Return true if the predicate is relational (not EQ or NE).
///
static bool isRelational(Predicate P) {
  return !isEquality(P);
}

/// Return true if the predicate is SGT or UGT.
///
static bool isGT(Predicate P) {
  return P == ICMP_SGT || P == ICMP_UGT;
}

/// Return true if the predicate is SLT or ULT.
///
static bool isLT(Predicate P) {
  return P == ICMP_SLT || P == ICMP_ULT;
}

/// Return true if the predicate is SGE or UGE.
///
static bool isGE(Predicate P) {
  return P == ICMP_SGE || P == ICMP_UGE;
}

/// Return true if the predicate is SLE or ULE.
///
static bool isLE(Predicate P) {
  return P == ICMP_SLE || P == ICMP_ULE;
}

/// Exchange the two operands to this instruction in such a way that it does
/// not modify the semantics of the instruction. The predicate value may be
/// changed to retain the same result if the predicate is order dependent
/// (e.g. ult).
/// Swap operands and adjust predicate.
void swapOperands() {
  setPredicate(getSwappedPredicate());
  Op<0>().swap(Op<1>());
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::ICmp;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1334};

1336//===----------------------------------------------------------------------===//
1337//                               FCmpInst Class
1338//===----------------------------------------------------------------------===//

1340/// This instruction compares its operands according to the predicate given
1341/// to the constructor. It only operates on floating point values or packed
1342/// vectors of floating point values. The operands must be identical types.
1343/// Represents a floating point comparison operator.
1344class FCmpInst: public CmpInst {
void AssertOK() {
  assert(isFPPredicate() && "Invalid FCmp predicate value")((isFPPredicate() && "Invalid FCmp predicate value") ?
 static_cast<void> (0) : __assert_fail ("isFPPredicate() && \"Invalid FCmp predicate value\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1346, __PRETTY_FUNCTION__));
  assert(getOperand(0)->getType() == getOperand(1)->getType() &&((getOperand(0)->getType() == getOperand(1)->getType() &&
 "Both operands to FCmp instruction are not of the same type!"
) ? static_cast<void> (0) : __assert_fail ("getOperand(0)->getType() == getOperand(1)->getType() && \"Both operands to FCmp instruction are not of the same type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1348, __PRETTY_FUNCTION__))
         "Both operands to FCmp instruction are not of the same type!")((getOperand(0)->getType() == getOperand(1)->getType() &&
 "Both operands to FCmp instruction are not of the same type!"
) ? static_cast<void> (0) : __assert_fail ("getOperand(0)->getType() == getOperand(1)->getType() && \"Both operands to FCmp instruction are not of the same type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1348, __PRETTY_FUNCTION__));
  // Check that the operands are the right type
  assert(getOperand(0)->getType()->isFPOrFPVectorTy() &&((getOperand(0)->getType()->isFPOrFPVectorTy() &&
 "Invalid operand types for FCmp instruction") ? static_cast<
void> (0) : __assert_fail ("getOperand(0)->getType()->isFPOrFPVectorTy() && \"Invalid operand types for FCmp instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1351, __PRETTY_FUNCTION__))
         "Invalid operand types for FCmp instruction")((getOperand(0)->getType()->isFPOrFPVectorTy() &&
 "Invalid operand types for FCmp instruction") ? static_cast<
void> (0) : __assert_fail ("getOperand(0)->getType()->isFPOrFPVectorTy() && \"Invalid operand types for FCmp instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1351, __PRETTY_FUNCTION__));
}

1354protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical FCmpInst
FCmpInst *cloneImpl() const;

1361public:
/// Constructor with insert-before-instruction semantics.
FCmpInst(
  Instruction *InsertBefore, ///< Where to insert
  Predicate pred,  ///< The predicate to use for the comparison
  Value *LHS,      ///< The left-hand-side of the expression
  Value *RHS,      ///< The right-hand-side of the expression
  const Twine &NameStr = ""  ///< Name of the instruction
) : CmpInst(makeCmpResultType(LHS->getType()),
            Instruction::FCmp, pred, LHS, RHS, NameStr,
            InsertBefore) {
  AssertOK();
}

/// Constructor with insert-at-end semantics.
FCmpInst(
  BasicBlock &InsertAtEnd, ///< Block to insert into.
  Predicate pred,  ///< The predicate to use for the comparison
  Value *LHS,      ///< The left-hand-side of the expression
  Value *RHS,      ///< The right-hand-side of the expression
  const Twine &NameStr = ""  ///< Name of the instruction
) : CmpInst(makeCmpResultType(LHS->getType()),
            Instruction::FCmp, pred, LHS, RHS, NameStr,
            &InsertAtEnd) {
  AssertOK();
}

/// Constructor with no-insertion semantics
FCmpInst(
  Predicate Pred, ///< The predicate to use for the comparison
  Value *LHS,     ///< The left-hand-side of the expression
  Value *RHS,     ///< The right-hand-side of the expression
  const Twine &NameStr = "", ///< Name of the instruction
  Instruction *FlagsSource = nullptr
) : CmpInst(makeCmpResultType(LHS->getType()), Instruction::FCmp, Pred, LHS,
            RHS, NameStr, nullptr, FlagsSource) {
  AssertOK();
}

/// @returns true if the predicate of this instruction is EQ or NE.
/// Determine if this is an equality predicate.
static bool isEquality(Predicate Pred) {
  return Pred == FCMP_OEQ || Pred == FCMP_ONE || Pred == FCMP_UEQ ||
         Pred == FCMP_UNE;
}

/// @returns true if the predicate of this instruction is EQ or NE.
/// Determine if this is an equality predicate.
bool isEquality() const { return isEquality(getPredicate()); }

/// @returns true if the predicate of this instruction is commutative.
/// Determine if this is a commutative predicate.
bool isCommutative() const {
  return isEquality() ||
         getPredicate() == FCMP_FALSE ||
         getPredicate() == FCMP_TRUE ||
         getPredicate() == FCMP_ORD ||
         getPredicate() == FCMP_UNO;
}

/// @returns true if the predicate is relational (not EQ or NE).
/// Determine if this a relational predicate.
bool isRelational() const { return !isEquality(); }

/// Exchange the two operands to this instruction in such a way that it does
/// not modify the semantics of the instruction. The predicate value may be
/// changed to retain the same result if the predicate is order dependent
/// (e.g. ult).
/// Swap operands and adjust predicate.
void swapOperands() {
  setPredicate(getSwappedPredicate());
  Op<0>().swap(Op<1>());
}

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::FCmp;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1442};

1444//===----------------------------------------------------------------------===//
1445/// This class represents a function call, abstracting a target
1446/// machine's calling convention.  This class uses low bit of the SubClassData
1447/// field to indicate whether or not this is a tail call.  The rest of the bits
1448/// hold the calling convention of the call.
1449///
1450class CallInst : public CallBase {
CallInst(const CallInst &CI);

/// Construct a CallInst given a range of arguments.
/// Construct a CallInst from a range of arguments
inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
                Instruction *InsertBefore);

inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                const Twine &NameStr, Instruction *InsertBefore)
    : CallInst(Ty, Func, Args, None, NameStr, InsertBefore) {}

/// Construct a CallInst given a range of arguments.
/// Construct a CallInst from a range of arguments
inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
                BasicBlock *InsertAtEnd);

explicit CallInst(FunctionType *Ty, Value *F, const Twine &NameStr,
                  Instruction *InsertBefore);

CallInst(FunctionType *ty, Value *F, const Twine &NameStr,
         BasicBlock *InsertAtEnd);

void init(FunctionType *FTy, Value *Func, ArrayRef<Value *> Args,
          ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);
void init(FunctionType *FTy, Value *Func, const Twine &NameStr);

/// Compute the number of operands to allocate.
static int ComputeNumOperands(int NumArgs, int NumBundleInputs = 0) {
  // We need one operand for the called function, plus the input operand
  // counts provided.
  return 1 + NumArgs + NumBundleInputs;
}

1486protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

CallInst *cloneImpl() const;

1492public:
static CallInst *Create(FunctionType *Ty, Value *F, const Twine &NameStr = "",
                        Instruction *InsertBefore = nullptr) {
  return new (ComputeNumOperands(0)) CallInst(Ty, F, NameStr, InsertBefore);
}

static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                        const Twine &NameStr,
                        Instruction *InsertBefore = nullptr) {
  return new (ComputeNumOperands(Args.size()))
      CallInst(Ty, Func, Args, None, NameStr, InsertBefore);
}

static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                        ArrayRef<OperandBundleDef> Bundles = None,
                        const Twine &NameStr = "",
                        Instruction *InsertBefore = nullptr) {
  const int NumOperands =
      ComputeNumOperands(Args.size(), CountBundleInputs(Bundles));
  const unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);

  return new (NumOperands, DescriptorBytes)
      CallInst(Ty, Func, Args, Bundles, NameStr, InsertBefore);
}

static CallInst *Create(FunctionType *Ty, Value *F, const Twine &NameStr,
                        BasicBlock *InsertAtEnd) {
  return new (ComputeNumOperands(0)) CallInst(Ty, F, NameStr, InsertAtEnd);
}

static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                        const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return new (ComputeNumOperands(Args.size()))
      CallInst(Ty, Func, Args, None, NameStr, InsertAtEnd);
}

static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                        ArrayRef<OperandBundleDef> Bundles,
                        const Twine &NameStr, BasicBlock *InsertAtEnd) {
  const int NumOperands =
      ComputeNumOperands(Args.size(), CountBundleInputs(Bundles));
  const unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);

  return new (NumOperands, DescriptorBytes)
      CallInst(Ty, Func, Args, Bundles, NameStr, InsertAtEnd);
}

static CallInst *Create(FunctionCallee Func, const Twine &NameStr = "",
                        Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), NameStr,
                InsertBefore);
}

static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
                        ArrayRef<OperandBundleDef> Bundles = None,
                        const Twine &NameStr = "",
                        Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), Args, Bundles,
                NameStr, InsertBefore);
}

static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
                        const Twine &NameStr,
                        Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), Args, NameStr,
                InsertBefore);
}

static CallInst *Create(FunctionCallee Func, const Twine &NameStr,
                        BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), NameStr,
                InsertAtEnd);
}

static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
                        const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), Args, NameStr,
                InsertAtEnd);
}

static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
                        ArrayRef<OperandBundleDef> Bundles,
                        const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), Args, Bundles,
                NameStr, InsertAtEnd);
}

/// Create a clone of \p CI with a different set of operand bundles and
/// insert it before \p InsertPt.
///
/// The returned call instruction is identical \p CI in every way except that
/// the operand bundles for the new instruction are set to the operand bundles
/// in \p Bundles.
static CallInst *Create(CallInst *CI, ArrayRef<OperandBundleDef> Bundles,
                        Instruction *InsertPt = nullptr);

/// Create a clone of \p CI with a different set of operand bundles and
/// insert it before \p InsertPt.
///
/// The returned call instruction is identical \p CI in every way except that
/// the operand bundle for the new instruction is set to the operand bundle
/// in \p Bundle.
static CallInst *CreateWithReplacedBundle(CallInst *CI,
                                          OperandBundleDef Bundle,
                                          Instruction *InsertPt = nullptr);

/// Generate the IR for a call to malloc:
/// 1. Compute the malloc call's argument as the specified type's size,
///    possibly multiplied by the array size if the array size is not
///    constant 1.
/// 2. Call malloc with that argument.
/// 3. Bitcast the result of the malloc call to the specified type.
static Instruction *CreateMalloc(Instruction *InsertBefore, Type *IntPtrTy,
                                 Type *AllocTy, Value *AllocSize,
                                 Value *ArraySize = nullptr,
                                 Function *MallocF = nullptr,
                                 const Twine &Name = "");
static Instruction *CreateMalloc(BasicBlock *InsertAtEnd, Type *IntPtrTy,
                                 Type *AllocTy, Value *AllocSize,
                                 Value *ArraySize = nullptr,
                                 Function *MallocF = nullptr,
                                 const Twine &Name = "");
static Instruction *CreateMalloc(Instruction *InsertBefore, Type *IntPtrTy,
                                 Type *AllocTy, Value *AllocSize,
                                 Value *ArraySize = nullptr,
                                 ArrayRef<OperandBundleDef> Bundles = None,
                                 Function *MallocF = nullptr,
                                 const Twine &Name = "");
static Instruction *CreateMalloc(BasicBlock *InsertAtEnd, Type *IntPtrTy,
                                 Type *AllocTy, Value *AllocSize,
                                 Value *ArraySize = nullptr,
                                 ArrayRef<OperandBundleDef> Bundles = None,
                                 Function *MallocF = nullptr,
                                 const Twine &Name = "");
/// Generate the IR for a call to the builtin free function.
static Instruction *CreateFree(Value *Source, Instruction *InsertBefore);
static Instruction *CreateFree(Value *Source, BasicBlock *InsertAtEnd);
static Instruction *CreateFree(Value *Source,
                               ArrayRef<OperandBundleDef> Bundles,
                               Instruction *InsertBefore);
static Instruction *CreateFree(Value *Source,
                               ArrayRef<OperandBundleDef> Bundles,
                               BasicBlock *InsertAtEnd);

// Note that 'musttail' implies 'tail'.
enum TailCallKind : unsigned {
  TCK_None = 0,
  TCK_Tail = 1,
  TCK_MustTail = 2,
  TCK_NoTail = 3,
  TCK_LAST = TCK_NoTail
};

using TailCallKindField = Bitfield::Element<TailCallKind, 0, 2, TCK_LAST>;
static_assert(
    Bitfield::areContiguous<TailCallKindField, CallBase::CallingConvField>(),
    "Bitfields must be contiguous");

TailCallKind getTailCallKind() const {
  return getSubclassData<TailCallKindField>();
}

bool isTailCall() const {
  TailCallKind Kind = getTailCallKind();
  return Kind == TCK_Tail || Kind == TCK_MustTail;
}

bool isMustTailCall() const { return getTailCallKind() == TCK_MustTail; }

bool isNoTailCall() const { return getTailCallKind() == TCK_NoTail; }

void setTailCallKind(TailCallKind TCK) {
  setSubclassData<TailCallKindField>(TCK);
}

void setTailCall(bool IsTc = true) {
  setTailCallKind(IsTc ? TCK_Tail : TCK_None);
}

/// Return true if the call can return twice
bool canReturnTwice() const { return hasFnAttr(Attribute::ReturnsTwice); }
void setCanReturnTwice() {
  addAttribute(AttributeList::FunctionIndex, Attribute::ReturnsTwice);
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Call;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

/// Updates profile metadata by scaling it by \p S / \p T.
void updateProfWeight(uint64_t S, uint64_t T);

1688private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}
1695};

1697CallInst::CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
                 BasicBlock *InsertAtEnd)
  : CallBase(Ty->getReturnType(), Instruction::Call,
             OperandTraits<CallBase>::op_end(this) -
                 (Args.size() + CountBundleInputs(Bundles) + 1),
             unsigned(Args.size() + CountBundleInputs(Bundles) + 1),
             InsertAtEnd) {
init(Ty, Func, Args, Bundles, NameStr);
1706}

1708CallInst::CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                 ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
                 Instruction *InsertBefore)
  : CallBase(Ty->getReturnType(), Instruction::Call,
             OperandTraits<CallBase>::op_end(this) -
                 (Args.size() + CountBundleInputs(Bundles) + 1),
             unsigned(Args.size() + CountBundleInputs(Bundles) + 1),
             InsertBefore) {
init(Ty, Func, Args, Bundles, NameStr);
1717}

1719//===----------------------------------------------------------------------===//
1720//                               SelectInst Class
1721//===----------------------------------------------------------------------===//

1723/// This class represents the LLVM 'select' instruction.
1724///
1725class SelectInst : public Instruction {
SelectInst(Value *C, Value *S1, Value *S2, const Twine &NameStr,
           Instruction *InsertBefore)
  : Instruction(S1->getType(), Instruction::Select,
                &Op<0>(), 3, InsertBefore) {
  init(C, S1, S2);
  setName(NameStr);
}

SelectInst(Value *C, Value *S1, Value *S2, const Twine &NameStr,
           BasicBlock *InsertAtEnd)
  : Instruction(S1->getType(), Instruction::Select,
                &Op<0>(), 3, InsertAtEnd) {
  init(C, S1, S2);
  setName(NameStr);
}

void init(Value *C, Value *S1, Value *S2) {
  assert(!areInvalidOperands(C, S1, S2) && "Invalid operands for select")((!areInvalidOperands(C, S1, S2) && "Invalid operands for select"
) ? static_cast<void> (0) : __assert_fail ("!areInvalidOperands(C, S1, S2) && \"Invalid operands for select\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1743, __PRETTY_FUNCTION__));
  Op<0>() = C;
  Op<1>() = S1;
  Op<2>() = S2;
}

1749protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

SelectInst *cloneImpl() const;

1755public:
static SelectInst *Create(Value *C, Value *S1, Value *S2,
                          const Twine &NameStr = "",
                          Instruction *InsertBefore = nullptr,
                          Instruction *MDFrom = nullptr) {
  SelectInst *Sel = new(3) SelectInst(C, S1, S2, NameStr, InsertBefore);
  if (MDFrom)
    Sel->copyMetadata(*MDFrom);
  return Sel;
}

static SelectInst *Create(Value *C, Value *S1, Value *S2,
                          const Twine &NameStr,
                          BasicBlock *InsertAtEnd) {
  return new(3) SelectInst(C, S1, S2, NameStr, InsertAtEnd);
}

const Value *getCondition() const { return Op<0>(); }
const Value *getTrueValue() const { return Op<1>(); }
const Value *getFalseValue() const { return Op<2>(); }
Value *getCondition() { return Op<0>(); }
Value *getTrueValue() { return Op<1>(); }
Value *getFalseValue() { return Op<2>(); }

void setCondition(Value *V) { Op<0>() = V; }
void setTrueValue(Value *V) { Op<1>() = V; }
void setFalseValue(Value *V) { Op<2>() = V; }

/// Swap the true and false values of the select instruction.
/// This doesn't swap prof metadata.
void swapValues() { Op<1>().swap(Op<2>()); }

/// Return a string if the specified operands are invalid
/// for a select operation, otherwise return null.
static const char *areInvalidOperands(Value *Cond, Value *True, Value *False);

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

OtherOps getOpcode() const {
  return static_cast<OtherOps>(Instruction::getOpcode());
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Select;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1805};

1807template <>
1808struct OperandTraits<SelectInst> : public FixedNumOperandTraits<SelectInst, 3> {
1809};

1811DEFINE_TRANSPARENT_OPERAND_ACCESSORS(SelectInst, Value)SelectInst::op_iterator SelectInst::op_begin() { return OperandTraits
<SelectInst>::op_begin(this); } SelectInst::const_op_iterator
 SelectInst::op_begin() const { return OperandTraits<SelectInst
>::op_begin(const_cast<SelectInst*>(this)); } SelectInst
::op_iterator SelectInst::op_end() { return OperandTraits<
SelectInst>::op_end(this); } SelectInst::const_op_iterator
 SelectInst::op_end() const { return OperandTraits<SelectInst
>::op_end(const_cast<SelectInst*>(this)); } Value *SelectInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<SelectInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<SelectInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1811, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<SelectInst>::op_begin(const_cast<SelectInst
*>(this))[i_nocapture].get()); } void SelectInst::setOperand
(unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<SelectInst>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<SelectInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1811, __PRETTY_FUNCTION__)); OperandTraits<SelectInst>
::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned SelectInst
::getNumOperands() const { return OperandTraits<SelectInst
>::operands(this); } template <int Idx_nocapture> Use
 &SelectInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
SelectInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }

1813//===----------------------------------------------------------------------===//
1814//                                VAArgInst Class
1815//===----------------------------------------------------------------------===//

1817/// This class represents the va_arg llvm instruction, which returns
1818/// an argument of the specified type given a va_list and increments that list
1819///
1820class VAArgInst : public UnaryInstruction {
1821protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

VAArgInst *cloneImpl() const;

1827public:
VAArgInst(Value *List, Type *Ty, const Twine &NameStr = "",
           Instruction *InsertBefore = nullptr)
  : UnaryInstruction(Ty, VAArg, List, InsertBefore) {
  setName(NameStr);
}

VAArgInst(Value *List, Type *Ty, const Twine &NameStr,
          BasicBlock *InsertAtEnd)
  : UnaryInstruction(Ty, VAArg, List, InsertAtEnd) {
  setName(NameStr);
}

Value *getPointerOperand() { return getOperand(0); }
const Value *getPointerOperand() const { return getOperand(0); }
static unsigned getPointerOperandIndex() { return 0U; }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == VAArg;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1851};

1853//===----------------------------------------------------------------------===//
1854//                                ExtractElementInst Class
1855//===----------------------------------------------------------------------===//

1857/// This instruction extracts a single (scalar)
1858/// element from a VectorType value
1859///
1860class ExtractElementInst : public Instruction {
ExtractElementInst(Value *Vec, Value *Idx, const Twine &NameStr = "",
                   Instruction *InsertBefore = nullptr);
ExtractElementInst(Value *Vec, Value *Idx, const Twine &NameStr,
                   BasicBlock *InsertAtEnd);

1866protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

ExtractElementInst *cloneImpl() const;

1872public:
static ExtractElementInst *Create(Value *Vec, Value *Idx,
                                 const Twine &NameStr = "",
                                 Instruction *InsertBefore = nullptr) {
  return new(2) ExtractElementInst(Vec, Idx, NameStr, InsertBefore);
}

static ExtractElementInst *Create(Value *Vec, Value *Idx,
                                 const Twine &NameStr,
                                 BasicBlock *InsertAtEnd) {
  return new(2) ExtractElementInst(Vec, Idx, NameStr, InsertAtEnd);
}

/// Return true if an extractelement instruction can be
/// formed with the specified operands.
static bool isValidOperands(const Value *Vec, const Value *Idx);

Value *getVectorOperand() { return Op<0>(); }
Value *getIndexOperand() { return Op<1>(); }
const Value *getVectorOperand() const { return Op<0>(); }
const Value *getIndexOperand() const { return Op<1>(); }

VectorType *getVectorOperandType() const {
  return cast<VectorType>(getVectorOperand()->getType());
}

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::ExtractElement;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1908};

1910template <>
1911struct OperandTraits<ExtractElementInst> :
public FixedNumOperandTraits<ExtractElementInst, 2> {
1913};

1915DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ExtractElementInst, Value)ExtractElementInst::op_iterator ExtractElementInst::op_begin(
) { return OperandTraits<ExtractElementInst>::op_begin(
this); } ExtractElementInst::const_op_iterator ExtractElementInst
::op_begin() const { return OperandTraits<ExtractElementInst
>::op_begin(const_cast<ExtractElementInst*>(this)); }
 ExtractElementInst::op_iterator ExtractElementInst::op_end()
 { return OperandTraits<ExtractElementInst>::op_end(this
); } ExtractElementInst::const_op_iterator ExtractElementInst
::op_end() const { return OperandTraits<ExtractElementInst
>::op_end(const_cast<ExtractElementInst*>(this)); } Value
 *ExtractElementInst::getOperand(unsigned i_nocapture) const {
 ((i_nocapture < OperandTraits<ExtractElementInst>::
operands(this) && "getOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ExtractElementInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1915, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<ExtractElementInst>::op_begin(const_cast
<ExtractElementInst*>(this))[i_nocapture].get()); } void
 ExtractElementInst::setOperand(unsigned i_nocapture, Value *
Val_nocapture) { ((i_nocapture < OperandTraits<ExtractElementInst
>::operands(this) && "setOperand() out of range!")
 ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ExtractElementInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1915, __PRETTY_FUNCTION__)); OperandTraits<ExtractElementInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 ExtractElementInst::getNumOperands() const { return OperandTraits
<ExtractElementInst>::operands(this); } template <int
 Idx_nocapture> Use &ExtractElementInst::Op() { return
 this->OpFrom<Idx_nocapture>(this); } template <int
 Idx_nocapture> const Use &ExtractElementInst::Op() const
 { return this->OpFrom<Idx_nocapture>(this); }

1917//===----------------------------------------------------------------------===//
1918//                                InsertElementInst Class
1919//===----------------------------------------------------------------------===//

1921/// This instruction inserts a single (scalar)
1922/// element into a VectorType value
1923///
1924class InsertElementInst : public Instruction {
InsertElementInst(Value *Vec, Value *NewElt, Value *Idx,
                  const Twine &NameStr = "",
                  Instruction *InsertBefore = nullptr);
InsertElementInst(Value *Vec, Value *NewElt, Value *Idx, const Twine &NameStr,
                  BasicBlock *InsertAtEnd);

1931protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

InsertElementInst *cloneImpl() const;

1937public:
static InsertElementInst *Create(Value *Vec, Value *NewElt, Value *Idx,
                                 const Twine &NameStr = "",
                                 Instruction *InsertBefore = nullptr) {
  return new(3) InsertElementInst(Vec, NewElt, Idx, NameStr, InsertBefore);
}

static InsertElementInst *Create(Value *Vec, Value *NewElt, Value *Idx,
                                 const Twine &NameStr,
                                 BasicBlock *InsertAtEnd) {
  return new(3) InsertElementInst(Vec, NewElt, Idx, NameStr, InsertAtEnd);
}

/// Return true if an insertelement instruction can be
/// formed with the specified operands.
static bool isValidOperands(const Value *Vec, const Value *NewElt,
                            const Value *Idx);

/// Overload to return most specific vector type.
///
VectorType *getType() const {
  return cast<VectorType>(Instruction::getType());
}

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::InsertElement;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
1971};

1973template <>
1974struct OperandTraits<InsertElementInst> :
public FixedNumOperandTraits<InsertElementInst, 3> {
1976};

1978DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertElementInst, Value)InsertElementInst::op_iterator InsertElementInst::op_begin() {
 return OperandTraits<InsertElementInst>::op_begin(this
); } InsertElementInst::const_op_iterator InsertElementInst::
op_begin() const { return OperandTraits<InsertElementInst>
::op_begin(const_cast<InsertElementInst*>(this)); } InsertElementInst
::op_iterator InsertElementInst::op_end() { return OperandTraits
<InsertElementInst>::op_end(this); } InsertElementInst::
const_op_iterator InsertElementInst::op_end() const { return OperandTraits
<InsertElementInst>::op_end(const_cast<InsertElementInst
*>(this)); } Value *InsertElementInst::getOperand(unsigned
 i_nocapture) const { ((i_nocapture < OperandTraits<InsertElementInst
>::operands(this) && "getOperand() out of range!")
 ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<InsertElementInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1978, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<InsertElementInst>::op_begin(const_cast
<InsertElementInst*>(this))[i_nocapture].get()); } void
 InsertElementInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((i_nocapture < OperandTraits<InsertElementInst>
::operands(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<InsertElementInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 1978, __PRETTY_FUNCTION__)); OperandTraits<InsertElementInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 InsertElementInst::getNumOperands() const { return OperandTraits
<InsertElementInst>::operands(this); } template <int
 Idx_nocapture> Use &InsertElementInst::Op() { return this
->OpFrom<Idx_nocapture>(this); } template <int Idx_nocapture
> const Use &InsertElementInst::Op() const { return this
->OpFrom<Idx_nocapture>(this); }

1980//===----------------------------------------------------------------------===//
1981//                           ShuffleVectorInst Class
1982//===----------------------------------------------------------------------===//

1984constexpr int UndefMaskElem = -1;

1986/// This instruction constructs a fixed permutation of two
1987/// input vectors.
1988///
1989/// For each element of the result vector, the shuffle mask selects an element
1990/// from one of the input vectors to copy to the result. Non-negative elements
1991/// in the mask represent an index into the concatenated pair of input vectors.
1992/// UndefMaskElem (-1) specifies that the result element is undefined.
1993///
1994/// For scalable vectors, all the elements of the mask must be 0 or -1. This
1995/// requirement may be relaxed in the future.
1996class ShuffleVectorInst : public Instruction {
SmallVector<int, 4> ShuffleMask;
Constant *ShuffleMaskForBitcode;

2000protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

ShuffleVectorInst *cloneImpl() const;

2006public:
ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
                  const Twine &NameStr = "",
                  Instruction *InsertBefor = nullptr);
ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
                  const Twine &NameStr, BasicBlock *InsertAtEnd);
ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
                  const Twine &NameStr = "",
                  Instruction *InsertBefor = nullptr);
ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
                  const Twine &NameStr, BasicBlock *InsertAtEnd);

void *operator new(size_t s) { return User::operator new(s, 2); }

/// Swap the operands and adjust the mask to preserve the semantics
/// of the instruction.
void commute();

/// Return true if a shufflevector instruction can be
/// formed with the specified operands.
static bool isValidOperands(const Value *V1, const Value *V2,
                            const Value *Mask);
static bool isValidOperands(const Value *V1, const Value *V2,
                            ArrayRef<int> Mask);

/// Overload to return most specific vector type.
///
VectorType *getType() const {
  return cast<VectorType>(Instruction::getType());
}

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Return the shuffle mask value of this instruction for the given element
/// index. Return UndefMaskElem if the element is undef.
int getMaskValue(unsigned Elt) const { return ShuffleMask[Elt]; }

/// Convert the input shuffle mask operand to a vector of integers. Undefined
/// elements of the mask are returned as UndefMaskElem.
static void getShuffleMask(const Constant *Mask,
                           SmallVectorImpl<int> &Result);

/// Return the mask for this instruction as a vector of integers. Undefined
/// elements of the mask are returned as UndefMaskElem.
void getShuffleMask(SmallVectorImpl<int> &Result) const {
  Result.assign(ShuffleMask.begin(), ShuffleMask.end());
}

/// Return the mask for this instruction, for use in bitcode.
///
/// TODO: This is temporary until we decide a new bitcode encoding for
/// shufflevector.
Constant *getShuffleMaskForBitcode() const { return ShuffleMaskForBitcode; }

static Constant *convertShuffleMaskForBitcode(ArrayRef<int> Mask,
                                              Type *ResultTy);

void setShuffleMask(ArrayRef<int> Mask);

ArrayRef<int> getShuffleMask() const { return ShuffleMask; }

/// Return true if this shuffle returns a vector with a different number of
/// elements than its source vectors.
/// Examples: shufflevector <4 x n> A, <4 x n> B, <1,2,3>
///           shufflevector <4 x n> A, <4 x n> B, <1,2,3,4,5>
bool changesLength() const {
  unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
                               ->getElementCount()
                               .getKnownMinValue();
  unsigned NumMaskElts = ShuffleMask.size();
  return NumSourceElts != NumMaskElts;
}

/// Return true if this shuffle returns a vector with a greater number of
/// elements than its source vectors.
/// Example: shufflevector <2 x n> A, <2 x n> B, <1,2,3>
bool increasesLength() const {
  unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
                               ->getElementCount()
                               .getKnownMinValue();
  unsigned NumMaskElts = ShuffleMask.size();
  return NumSourceElts < NumMaskElts;
}

/// Return true if this shuffle mask chooses elements from exactly one source
/// vector.
/// Example: <7,5,undef,7>
/// This assumes that vector operands are the same length as the mask.
static bool isSingleSourceMask(ArrayRef<int> Mask);
static bool isSingleSourceMask(const Constant *Mask) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2097, __PRETTY_FUNCTION__));
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isSingleSourceMask(MaskAsInts);
}

/// Return true if this shuffle chooses elements from exactly one source
/// vector without changing the length of that vector.
/// Example: shufflevector <4 x n> A, <4 x n> B, <3,0,undef,3>
/// TODO: Optionally allow length-changing shuffles.
bool isSingleSource() const {
  return !changesLength() && isSingleSourceMask(ShuffleMask);
}

/// Return true if this shuffle mask chooses elements from exactly one source
/// vector without lane crossings. A shuffle using this mask is not
/// necessarily a no-op because it may change the number of elements from its
/// input vectors or it may provide demanded bits knowledge via undef lanes.
/// Example: <undef,undef,2,3>
static bool isIdentityMask(ArrayRef<int> Mask);
static bool isIdentityMask(const Constant *Mask) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2118, __PRETTY_FUNCTION__));
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isIdentityMask(MaskAsInts);
}

/// Return true if this shuffle chooses elements from exactly one source
/// vector without lane crossings and does not change the number of elements
/// from its input vectors.
/// Example: shufflevector <4 x n> A, <4 x n> B, <4,undef,6,undef>
bool isIdentity() const {
  return !changesLength() && isIdentityMask(ShuffleMask);
}

/// Return true if this shuffle lengthens exactly one source vector with
/// undefs in the high elements.
bool isIdentityWithPadding() const;

/// Return true if this shuffle extracts the first N elements of exactly one
/// source vector.
bool isIdentityWithExtract() const;

/// Return true if this shuffle concatenates its 2 source vectors. This
/// returns false if either input is undefined. In that case, the shuffle is
/// is better classified as an identity with padding operation.
bool isConcat() const;

/// Return true if this shuffle mask chooses elements from its source vectors
/// without lane crossings. A shuffle using this mask would be
/// equivalent to a vector select with a constant condition operand.
/// Example: <4,1,6,undef>
/// This returns false if the mask does not choose from both input vectors.
/// In that case, the shuffle is better classified as an identity shuffle.
/// This assumes that vector operands are the same length as the mask
/// (a length-changing shuffle can never be equivalent to a vector select).
static bool isSelectMask(ArrayRef<int> Mask);
static bool isSelectMask(const Constant *Mask) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2155, __PRETTY_FUNCTION__));
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isSelectMask(MaskAsInts);
}

/// Return true if this shuffle chooses elements from its source vectors
/// without lane crossings and all operands have the same number of elements.
/// In other words, this shuffle is equivalent to a vector select with a
/// constant condition operand.
/// Example: shufflevector <4 x n> A, <4 x n> B, <undef,1,6,3>
/// This returns false if the mask does not choose from both input vectors.
/// In that case, the shuffle is better classified as an identity shuffle.
/// TODO: Optionally allow length-changing shuffles.
bool isSelect() const {
  return !changesLength() && isSelectMask(ShuffleMask);
}

/// Return true if this shuffle mask swaps the order of elements from exactly
/// one source vector.
/// Example: <7,6,undef,4>
/// This assumes that vector operands are the same length as the mask.
static bool isReverseMask(ArrayRef<int> Mask);
static bool isReverseMask(const Constant *Mask) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2179, __PRETTY_FUNCTION__));
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isReverseMask(MaskAsInts);
}

/// Return true if this shuffle swaps the order of elements from exactly
/// one source vector.
/// Example: shufflevector <4 x n> A, <4 x n> B, <3,undef,1,undef>
/// TODO: Optionally allow length-changing shuffles.
bool isReverse() const {
  return !changesLength() && isReverseMask(ShuffleMask);
}

/// Return true if this shuffle mask chooses all elements with the same value
/// as the first element of exactly one source vector.
/// Example: <4,undef,undef,4>
/// This assumes that vector operands are the same length as the mask.
static bool isZeroEltSplatMask(ArrayRef<int> Mask);
static bool isZeroEltSplatMask(const Constant *Mask) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2199, __PRETTY_FUNCTION__));
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isZeroEltSplatMask(MaskAsInts);
}

/// Return true if all elements of this shuffle are the same value as the
/// first element of exactly one source vector without changing the length
/// of that vector.
/// Example: shufflevector <4 x n> A, <4 x n> B, <undef,0,undef,0>
/// TODO: Optionally allow length-changing shuffles.
/// TODO: Optionally allow splats from other elements.
bool isZeroEltSplat() const {
  return !changesLength() && isZeroEltSplatMask(ShuffleMask);
}

/// Return true if this shuffle mask is a transpose mask.
/// Transpose vector masks transpose a 2xn matrix. They read corresponding
/// even- or odd-numbered vector elements from two n-dimensional source
/// vectors and write each result into consecutive elements of an
/// n-dimensional destination vector. Two shuffles are necessary to complete
/// the transpose, one for the even elements and another for the odd elements.
/// This description closely follows how the TRN1 and TRN2 AArch64
/// instructions operate.
///
/// For example, a simple 2x2 matrix can be transposed with:
///
///   ; Original matrix
///   m0 = < a, b >
///   m1 = < c, d >
///
///   ; Transposed matrix
///   t0 = < a, c > = shufflevector m0, m1, < 0, 2 >
///   t1 = < b, d > = shufflevector m0, m1, < 1, 3 >
///
/// For matrices having greater than n columns, the resulting nx2 transposed
/// matrix is stored in two result vectors such that one vector contains
/// interleaved elements from all the even-numbered rows and the other vector
/// contains interleaved elements from all the odd-numbered rows. For example,
/// a 2x4 matrix can be transposed with:
///
///   ; Original matrix
///   m0 = < a, b, c, d >
///   m1 = < e, f, g, h >
///
///   ; Transposed matrix
///   t0 = < a, e, c, g > = shufflevector m0, m1 < 0, 4, 2, 6 >
///   t1 = < b, f, d, h > = shufflevector m0, m1 < 1, 5, 3, 7 >
static bool isTransposeMask(ArrayRef<int> Mask);
static bool isTransposeMask(const Constant *Mask) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2249, __PRETTY_FUNCTION__));
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isTransposeMask(MaskAsInts);
}

/// Return true if this shuffle transposes the elements of its inputs without
/// changing the length of the vectors. This operation may also be known as a
/// merge or interleave. See the description for isTransposeMask() for the
/// exact specification.
/// Example: shufflevector <4 x n> A, <4 x n> B, <0,4,2,6>
bool isTranspose() const {
  return !changesLength() && isTransposeMask(ShuffleMask);
}

/// Return true if this shuffle mask is an extract subvector mask.
/// A valid extract subvector mask returns a smaller vector from a single
/// source operand. The base extraction index is returned as well.
static bool isExtractSubvectorMask(ArrayRef<int> Mask, int NumSrcElts,
                                   int &Index);
static bool isExtractSubvectorMask(const Constant *Mask, int NumSrcElts,
                                   int &Index) {
  assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.")((Mask->getType()->isVectorTy() && "Shuffle needs vector constant."
) ? static_cast<void> (0) : __assert_fail ("Mask->getType()->isVectorTy() && \"Shuffle needs vector constant.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2271, __PRETTY_FUNCTION__));
  // Not possible to express a shuffle mask for a scalable vector for this
  // case.
  if (isa<ScalableVectorType>(Mask->getType()))
    return false;
  SmallVector<int, 16> MaskAsInts;
  getShuffleMask(Mask, MaskAsInts);
  return isExtractSubvectorMask(MaskAsInts, NumSrcElts, Index);
}

/// Return true if this shuffle mask is an extract subvector mask.
bool isExtractSubvectorMask(int &Index) const {
  // Not possible to express a shuffle mask for a scalable vector for this
  // case.
  if (isa<ScalableVectorType>(getType()))
    return false;

  int NumSrcElts =
      cast<FixedVectorType>(Op<0>()->getType())->getNumElements();
  return isExtractSubvectorMask(ShuffleMask, NumSrcElts, Index);
}

/// Change values in a shuffle permute mask assuming the two vector operands
/// of length InVecNumElts have swapped position.
static void commuteShuffleMask(MutableArrayRef<int> Mask,
                               unsigned InVecNumElts) {
  for (int &Idx : Mask) {
    if (Idx == -1)
      continue;
    Idx = Idx < (int)InVecNumElts ? Idx + InVecNumElts : Idx - InVecNumElts;
    assert(Idx >= 0 && Idx < (int)InVecNumElts * 2 &&((Idx >= 0 && Idx < (int)InVecNumElts * 2 &&
 "shufflevector mask index out of range") ? static_cast<void
> (0) : __assert_fail ("Idx >= 0 && Idx < (int)InVecNumElts * 2 && \"shufflevector mask index out of range\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2302, __PRETTY_FUNCTION__))
           "shufflevector mask index out of range")((Idx >= 0 && Idx < (int)InVecNumElts * 2 &&
 "shufflevector mask index out of range") ? static_cast<void
> (0) : __assert_fail ("Idx >= 0 && Idx < (int)InVecNumElts * 2 && \"shufflevector mask index out of range\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2302, __PRETTY_FUNCTION__));
  }
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::ShuffleVector;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
2313};

2315template <>
2316struct OperandTraits<ShuffleVectorInst>
  : public FixedNumOperandTraits<ShuffleVectorInst, 2> {};

2319DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ShuffleVectorInst, Value)ShuffleVectorInst::op_iterator ShuffleVectorInst::op_begin() {
 return OperandTraits<ShuffleVectorInst>::op_begin(this
); } ShuffleVectorInst::const_op_iterator ShuffleVectorInst::
op_begin() const { return OperandTraits<ShuffleVectorInst>
::op_begin(const_cast<ShuffleVectorInst*>(this)); } ShuffleVectorInst
::op_iterator ShuffleVectorInst::op_end() { return OperandTraits
<ShuffleVectorInst>::op_end(this); } ShuffleVectorInst::
const_op_iterator ShuffleVectorInst::op_end() const { return OperandTraits
<ShuffleVectorInst>::op_end(const_cast<ShuffleVectorInst
*>(this)); } Value *ShuffleVectorInst::getOperand(unsigned
 i_nocapture) const { ((i_nocapture < OperandTraits<ShuffleVectorInst
>::operands(this) && "getOperand() out of range!")
 ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ShuffleVectorInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2319, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<ShuffleVectorInst>::op_begin(const_cast
<ShuffleVectorInst*>(this))[i_nocapture].get()); } void
 ShuffleVectorInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((i_nocapture < OperandTraits<ShuffleVectorInst>
::operands(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ShuffleVectorInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2319, __PRETTY_FUNCTION__)); OperandTraits<ShuffleVectorInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 ShuffleVectorInst::getNumOperands() const { return OperandTraits
<ShuffleVectorInst>::operands(this); } template <int
 Idx_nocapture> Use &ShuffleVectorInst::Op() { return this
->OpFrom<Idx_nocapture>(this); } template <int Idx_nocapture
> const Use &ShuffleVectorInst::Op() const { return this
->OpFrom<Idx_nocapture>(this); }

2321//===----------------------------------------------------------------------===//
2322//                                ExtractValueInst Class
2323//===----------------------------------------------------------------------===//

2325/// This instruction extracts a struct member or array
2326/// element value from an aggregate value.
2327///
2328class ExtractValueInst : public UnaryInstruction {
SmallVector<unsigned, 4> Indices;

ExtractValueInst(const ExtractValueInst &EVI);

/// Constructors - Create a extractvalue instruction with a base aggregate
/// value and a list of indices.  The first ctor can optionally insert before
/// an existing instruction, the second appends the new instruction to the
/// specified BasicBlock.
inline ExtractValueInst(Value *Agg,
                        ArrayRef<unsigned> Idxs,
                        const Twine &NameStr,
                        Instruction *InsertBefore);
inline ExtractValueInst(Value *Agg,
                        ArrayRef<unsigned> Idxs,
                        const Twine &NameStr, BasicBlock *InsertAtEnd);

void init(ArrayRef<unsigned> Idxs, const Twine &NameStr);

2347protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

ExtractValueInst *cloneImpl() const;

2353public:
static ExtractValueInst *Create(Value *Agg,
                                ArrayRef<unsigned> Idxs,
                                const Twine &NameStr = "",
                                Instruction *InsertBefore = nullptr) {
  return new
    ExtractValueInst(Agg, Idxs, NameStr, InsertBefore);
}

static ExtractValueInst *Create(Value *Agg,
                                ArrayRef<unsigned> Idxs,
                                const Twine &NameStr,
                                BasicBlock *InsertAtEnd) {
  return new ExtractValueInst(Agg, Idxs, NameStr, InsertAtEnd);
}

/// Returns the type of the element that would be extracted
/// with an extractvalue instruction with the specified parameters.
///
/// Null is returned if the indices are invalid for the specified type.
static Type *getIndexedType(Type *Agg, ArrayRef<unsigned> Idxs);

using idx_iterator = const unsigned*;

inline idx_iterator idx_begin() const { return Indices.begin(); }
inline idx_iterator idx_end()   const { return Indices.end(); }
inline iterator_range<idx_iterator> indices() const {
  return make_range(idx_begin(), idx_end());
}

Value *getAggregateOperand() {
  return getOperand(0);
}
const Value *getAggregateOperand() const {
  return getOperand(0);
}
static unsigned getAggregateOperandIndex() {
  return 0U;                      // get index for modifying correct operand
}

ArrayRef<unsigned> getIndices() const {
  return Indices;
}

unsigned getNumIndices() const {
  return (unsigned)Indices.size();
}

bool hasIndices() const {
  return true;
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::ExtractValue;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
2412};

2414ExtractValueInst::ExtractValueInst(Value *Agg,
                                 ArrayRef<unsigned> Idxs,
                                 const Twine &NameStr,
                                 Instruction *InsertBefore)
: UnaryInstruction(checkGEPType(getIndexedType(Agg->getType(), Idxs)),
                   ExtractValue, Agg, InsertBefore) {
init(Idxs, NameStr);
2421}

2423ExtractValueInst::ExtractValueInst(Value *Agg,
                                 ArrayRef<unsigned> Idxs,
                                 const Twine &NameStr,
                                 BasicBlock *InsertAtEnd)
: UnaryInstruction(checkGEPType(getIndexedType(Agg->getType(), Idxs)),
                   ExtractValue, Agg, InsertAtEnd) {
init(Idxs, NameStr);
2430}

2432//===----------------------------------------------------------------------===//
2433//                                InsertValueInst Class
2434//===----------------------------------------------------------------------===//

2436/// This instruction inserts a struct field of array element
2437/// value into an aggregate value.
2438///
2439class InsertValueInst : public Instruction {
SmallVector<unsigned, 4> Indices;

InsertValueInst(const InsertValueInst &IVI);

/// Constructors - Create a insertvalue instruction with a base aggregate
/// value, a value to insert, and a list of indices.  The first ctor can
/// optionally insert before an existing instruction, the second appends
/// the new instruction to the specified BasicBlock.
inline InsertValueInst(Value *Agg, Value *Val,
                       ArrayRef<unsigned> Idxs,
                       const Twine &NameStr,
                       Instruction *InsertBefore);
inline InsertValueInst(Value *Agg, Value *Val,
                       ArrayRef<unsigned> Idxs,
                       const Twine &NameStr, BasicBlock *InsertAtEnd);

/// Constructors - These two constructors are convenience methods because one
/// and two index insertvalue instructions are so common.
InsertValueInst(Value *Agg, Value *Val, unsigned Idx,
                const Twine &NameStr = "",
                Instruction *InsertBefore = nullptr);
InsertValueInst(Value *Agg, Value *Val, unsigned Idx, const Twine &NameStr,
                BasicBlock *InsertAtEnd);

void init(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
          const Twine &NameStr);

2467protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

InsertValueInst *cloneImpl() const;

2473public:
// allocate space for exactly two operands
void *operator new(size_t s) {
  return User::operator new(s, 2);
}

static InsertValueInst *Create(Value *Agg, Value *Val,
                               ArrayRef<unsigned> Idxs,
                               const Twine &NameStr = "",
                               Instruction *InsertBefore = nullptr) {
  return new InsertValueInst(Agg, Val, Idxs, NameStr, InsertBefore);
}

static InsertValueInst *Create(Value *Agg, Value *Val,
                               ArrayRef<unsigned> Idxs,
                               const Twine &NameStr,
                               BasicBlock *InsertAtEnd) {
  return new InsertValueInst(Agg, Val, Idxs, NameStr, InsertAtEnd);
}

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

using idx_iterator = const unsigned*;

inline idx_iterator idx_begin() const { return Indices.begin(); }
inline idx_iterator idx_end()   const { return Indices.end(); }
inline iterator_range<idx_iterator> indices() const {
  return make_range(idx_begin(), idx_end());
}

Value *getAggregateOperand() {
  return getOperand(0);
}
const Value *getAggregateOperand() const {
  return getOperand(0);
}
static unsigned getAggregateOperandIndex() {
  return 0U;                      // get index for modifying correct operand
}

Value *getInsertedValueOperand() {
  return getOperand(1);
}
const Value *getInsertedValueOperand() const {
  return getOperand(1);
}
static unsigned getInsertedValueOperandIndex() {
  return 1U;                      // get index for modifying correct operand
}

ArrayRef<unsigned> getIndices() const {
  return Indices;
}

unsigned getNumIndices() const {
  return (unsigned)Indices.size();
}

bool hasIndices() const {
  return true;
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::InsertValue;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
2543};

2545template <>
2546struct OperandTraits<InsertValueInst> :
public FixedNumOperandTraits<InsertValueInst, 2> {
2548};

2550InsertValueInst::InsertValueInst(Value *Agg,
                               Value *Val,
                               ArrayRef<unsigned> Idxs,
                               const Twine &NameStr,
                               Instruction *InsertBefore)
: Instruction(Agg->getType(), InsertValue,
              OperandTraits<InsertValueInst>::op_begin(this),
              2, InsertBefore) {
init(Agg, Val, Idxs, NameStr);
2559}

2561InsertValueInst::InsertValueInst(Value *Agg,
                               Value *Val,
                               ArrayRef<unsigned> Idxs,
                               const Twine &NameStr,
                               BasicBlock *InsertAtEnd)
: Instruction(Agg->getType(), InsertValue,
              OperandTraits<InsertValueInst>::op_begin(this),
              2, InsertAtEnd) {
init(Agg, Val, Idxs, NameStr);
2570}

2572DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertValueInst, Value)InsertValueInst::op_iterator InsertValueInst::op_begin() { return
 OperandTraits<InsertValueInst>::op_begin(this); } InsertValueInst
::const_op_iterator InsertValueInst::op_begin() const { return
 OperandTraits<InsertValueInst>::op_begin(const_cast<
InsertValueInst*>(this)); } InsertValueInst::op_iterator InsertValueInst
::op_end() { return OperandTraits<InsertValueInst>::op_end
(this); } InsertValueInst::const_op_iterator InsertValueInst::
op_end() const { return OperandTraits<InsertValueInst>::
op_end(const_cast<InsertValueInst*>(this)); } Value *InsertValueInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<InsertValueInst>::operands(this) &&
 "getOperand() out of range!") ? static_cast<void> (0) :
 __assert_fail ("i_nocapture < OperandTraits<InsertValueInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2572, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<InsertValueInst>::op_begin(const_cast<
InsertValueInst*>(this))[i_nocapture].get()); } void InsertValueInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
i_nocapture < OperandTraits<InsertValueInst>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<InsertValueInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2572, __PRETTY_FUNCTION__)); OperandTraits<InsertValueInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 InsertValueInst::getNumOperands() const { return OperandTraits
<InsertValueInst>::operands(this); } template <int Idx_nocapture
> Use &InsertValueInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
 const Use &InsertValueInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }

2574//===----------------------------------------------------------------------===//
2575//                               PHINode Class
2576//===----------------------------------------------------------------------===//

2578// PHINode - The PHINode class is used to represent the magical mystical PHI
2579// node, that can not exist in nature, but can be synthesized in a computer
2580// scientist's overactive imagination.
2581//
2582class PHINode : public Instruction {
/// The number of operands actually allocated.  NumOperands is
/// the number actually in use.
unsigned ReservedSpace;

PHINode(const PHINode &PN);

explicit PHINode(Type *Ty, unsigned NumReservedValues,
                 const Twine &NameStr = "",
                 Instruction *InsertBefore = nullptr)
  : Instruction(Ty, Instruction::PHI, nullptr, 0, InsertBefore),
    ReservedSpace(NumReservedValues) {
  setName(NameStr);
  allocHungoffUses(ReservedSpace);
}

PHINode(Type *Ty, unsigned NumReservedValues, const Twine &NameStr,
        BasicBlock *InsertAtEnd)
  : Instruction(Ty, Instruction::PHI, nullptr, 0, InsertAtEnd),
    ReservedSpace(NumReservedValues) {
  setName(NameStr);
  allocHungoffUses(ReservedSpace);
}

2606protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

PHINode *cloneImpl() const;

// allocHungoffUses - this is more complicated than the generic
// User::allocHungoffUses, because we have to allocate Uses for the incoming
// values and pointers to the incoming blocks, all in one allocation.
void allocHungoffUses(unsigned N) {
  User::allocHungoffUses(N, /* IsPhi */ true);
}

2619public:
/// Constructors - NumReservedValues is a hint for the number of incoming
/// edges that this phi node will have (use 0 if you really have no idea).
static PHINode *Create(Type *Ty, unsigned NumReservedValues,
                       const Twine &NameStr = "",
                       Instruction *InsertBefore = nullptr) {
  return new PHINode(Ty, NumReservedValues, NameStr, InsertBefore);
}

static PHINode *Create(Type *Ty, unsigned NumReservedValues,
                       const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return new PHINode(Ty, NumReservedValues, NameStr, InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

// Block iterator interface. This provides access to the list of incoming
// basic blocks, which parallels the list of incoming values.

using block_iterator = BasicBlock **;
using const_block_iterator = BasicBlock * const *;

block_iterator block_begin() {
  return reinterpret_cast<block_iterator>(op_begin() + ReservedSpace);
}

const_block_iterator block_begin() const {
  return reinterpret_cast<const_block_iterator>(op_begin() + ReservedSpace);
}

block_iterator block_end() {
  return block_begin() + getNumOperands();
}

const_block_iterator block_end() const {
  return block_begin() + getNumOperands();
}

iterator_range<block_iterator> blocks() {
  return make_range(block_begin(), block_end());
}

iterator_range<const_block_iterator> blocks() const {
  return make_range(block_begin(), block_end());
}

op_range incoming_values() { return operands(); }

const_op_range incoming_values() const { return operands(); }

/// Return the number of incoming edges
///
unsigned getNumIncomingValues() const { return getNumOperands(); }

/// Return incoming value number x
///
Value *getIncomingValue(unsigned i) const {
  return getOperand(i);
}
void setIncomingValue(unsigned i, Value *V) {
  assert(V && "PHI node got a null value!")((V && "PHI node got a null value!") ? static_cast<
void> (0) : __assert_fail ("V && \"PHI node got a null value!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2680, __PRETTY_FUNCTION__));
  assert(getType() == V->getType() &&((getType() == V->getType() && "All operands to PHI node must be the same type as the PHI node!"
) ? static_cast<void> (0) : __assert_fail ("getType() == V->getType() && \"All operands to PHI node must be the same type as the PHI node!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2682, __PRETTY_FUNCTION__))
         "All operands to PHI node must be the same type as the PHI node!")((getType() == V->getType() && "All operands to PHI node must be the same type as the PHI node!"
) ? static_cast<void> (0) : __assert_fail ("getType() == V->getType() && \"All operands to PHI node must be the same type as the PHI node!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2682, __PRETTY_FUNCTION__));
  setOperand(i, V);
}

static unsigned getOperandNumForIncomingValue(unsigned i) {
  return i;
}

static unsigned getIncomingValueNumForOperand(unsigned i) {
  return i;
}

/// Return incoming basic block number @p i.
///
BasicBlock *getIncomingBlock(unsigned i) const {
  return block_begin()[i];
}

/// Return incoming basic block corresponding
/// to an operand of the PHI.
///
BasicBlock *getIncomingBlock(const Use &U) const {
  assert(this == U.getUser() && "Iterator doesn't point to PHI's Uses?")((this == U.getUser() && "Iterator doesn't point to PHI's Uses?"
) ? static_cast<void> (0) : __assert_fail ("this == U.getUser() && \"Iterator doesn't point to PHI's Uses?\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2704, __PRETTY_FUNCTION__));
  return getIncomingBlock(unsigned(&U - op_begin()));
}

/// Return incoming basic block corresponding
/// to value use iterator.
///
BasicBlock *getIncomingBlock(Value::const_user_iterator I) const {
  return getIncomingBlock(I.getUse());
}

void setIncomingBlock(unsigned i, BasicBlock *BB) {
  assert(BB && "PHI node got a null basic block!")((BB && "PHI node got a null basic block!") ? static_cast
<void> (0) : __assert_fail ("BB && \"PHI node got a null basic block!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2716, __PRETTY_FUNCTION__));
  block_begin()[i] = BB;
}

/// Replace every incoming basic block \p Old to basic block \p New.
void replaceIncomingBlockWith(const BasicBlock *Old, BasicBlock *New) {
  assert(New && Old && "PHI node got a null basic block!")((New && Old && "PHI node got a null basic block!"
) ? static_cast<void> (0) : __assert_fail ("New && Old && \"PHI node got a null basic block!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2722, __PRETTY_FUNCTION__));
  for (unsigned Op = 0, NumOps = getNumOperands(); Op != NumOps; ++Op)
    if (getIncomingBlock(Op) == Old)
      setIncomingBlock(Op, New);
}

/// Add an incoming value to the end of the PHI list
///
void addIncoming(Value *V, BasicBlock *BB) {
  if (getNumOperands() == ReservedSpace)
    growOperands();  // Get more space!
  // Initialize some new operands.
  setNumHungOffUseOperands(getNumOperands() + 1);
  setIncomingValue(getNumOperands() - 1, V);
  setIncomingBlock(getNumOperands() - 1, BB);
}

/// Remove an incoming value.  This is useful if a
/// predecessor basic block is deleted.  The value removed is returned.
///
/// If the last incoming value for a PHI node is removed (and DeletePHIIfEmpty
/// is true), the PHI node is destroyed and any uses of it are replaced with
/// dummy values.  The only time there should be zero incoming values to a PHI
/// node is when the block is dead, so this strategy is sound.
///
Value *removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty = true);

Value *removeIncomingValue(const BasicBlock *BB, bool DeletePHIIfEmpty=true) {
  int Idx = getBasicBlockIndex(BB);
  assert(Idx >= 0 && "Invalid basic block argument to remove!")((Idx >= 0 && "Invalid basic block argument to remove!"
) ? static_cast<void> (0) : __assert_fail ("Idx >= 0 && \"Invalid basic block argument to remove!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2751, __PRETTY_FUNCTION__));
  return removeIncomingValue(Idx, DeletePHIIfEmpty);
}

/// Return the first index of the specified basic
/// block in the value list for this PHI.  Returns -1 if no instance.
///
int getBasicBlockIndex(const BasicBlock *BB) const {
  for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
    if (block_begin()[i] == BB)
      return i;
  return -1;
}

Value *getIncomingValueForBlock(const BasicBlock *BB) const {
  int Idx = getBasicBlockIndex(BB);
  assert(Idx >= 0 && "Invalid basic block argument!")((Idx >= 0 && "Invalid basic block argument!") ? static_cast
<void> (0) : __assert_fail ("Idx >= 0 && \"Invalid basic block argument!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2767, __PRETTY_FUNCTION__));
  return getIncomingValue(Idx);
}

/// Set every incoming value(s) for block \p BB to \p V.
void setIncomingValueForBlock(const BasicBlock *BB, Value *V) {
  assert(BB && "PHI node got a null basic block!")((BB && "PHI node got a null basic block!") ? static_cast
<void> (0) : __assert_fail ("BB && \"PHI node got a null basic block!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2773, __PRETTY_FUNCTION__));
  bool Found = false;
  for (unsigned Op = 0, NumOps = getNumOperands(); Op != NumOps; ++Op)
    if (getIncomingBlock(Op) == BB) {
      Found = true;
      setIncomingValue(Op, V);
    }
  (void)Found;
  assert(Found && "Invalid basic block argument to set!")((Found && "Invalid basic block argument to set!") ? static_cast
<void> (0) : __assert_fail ("Found && \"Invalid basic block argument to set!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2781, __PRETTY_FUNCTION__));
}

/// If the specified PHI node always merges together the
/// same value, return the value, otherwise return null.
Value *hasConstantValue() const;

/// Whether the specified PHI node always merges
/// together the same value, assuming undefs are equal to a unique
/// non-undef value.
bool hasConstantOrUndefValue() const;

/// If the PHI node is complete which means all of its parent's predecessors
/// have incoming value in this PHI, return true, otherwise return false.
bool isComplete() const {
  return llvm::all_of(predecessors(getParent()),
                      [this](const BasicBlock *Pred) {
                        return getBasicBlockIndex(Pred) >= 0;
                      });
}

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::PHI;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

2810private:
void growOperands();
2812};

2814template <>
2815struct OperandTraits<PHINode> : public HungoffOperandTraits<2> {
2816};

2818DEFINE_TRANSPARENT_OPERAND_ACCESSORS(PHINode, Value)PHINode::op_iterator PHINode::op_begin() { return OperandTraits
<PHINode>::op_begin(this); } PHINode::const_op_iterator
 PHINode::op_begin() const { return OperandTraits<PHINode>
::op_begin(const_cast<PHINode*>(this)); } PHINode::op_iterator
 PHINode::op_end() { return OperandTraits<PHINode>::op_end
(this); } PHINode::const_op_iterator PHINode::op_end() const {
 return OperandTraits<PHINode>::op_end(const_cast<PHINode
*>(this)); } Value *PHINode::getOperand(unsigned i_nocapture
) const { ((i_nocapture < OperandTraits<PHINode>::operands
(this) && "getOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<PHINode>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2818, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<PHINode>::op_begin(const_cast<PHINode
*>(this))[i_nocapture].get()); } void PHINode::setOperand(
unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<PHINode>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<PHINode>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2818, __PRETTY_FUNCTION__)); OperandTraits<PHINode>::
op_begin(this)[i_nocapture] = Val_nocapture; } unsigned PHINode
::getNumOperands() const { return OperandTraits<PHINode>
::operands(this); } template <int Idx_nocapture> Use &
PHINode::Op() { return this->OpFrom<Idx_nocapture>(this
); } template <int Idx_nocapture> const Use &PHINode
::Op() const { return this->OpFrom<Idx_nocapture>(this
); }

2820//===----------------------------------------------------------------------===//
2821//                           LandingPadInst Class
2822//===----------------------------------------------------------------------===//

2824//===---------------------------------------------------------------------------
2825/// The landingpad instruction holds all of the information
2826/// necessary to generate correct exception handling. The landingpad instruction
2827/// cannot be moved from the top of a landing pad block, which itself is
2828/// accessible only from the 'unwind' edge of an invoke. This uses the
2829/// SubclassData field in Value to store whether or not the landingpad is a
2830/// cleanup.
2831///
2832class LandingPadInst : public Instruction {
using CleanupField = BoolBitfieldElementT<0>;

/// The number of operands actually allocated.  NumOperands is
/// the number actually in use.
unsigned ReservedSpace;

LandingPadInst(const LandingPadInst &LP);

2841public:
enum ClauseType { Catch, Filter };

2844private:
explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
                        const Twine &NameStr, Instruction *InsertBefore);
explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
                        const Twine &NameStr, BasicBlock *InsertAtEnd);

// Allocate space for exactly zero operands.
void *operator new(size_t s) {
  return User::operator new(s);
}

void growOperands(unsigned Size);
void init(unsigned NumReservedValues, const Twine &NameStr);

2858protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

LandingPadInst *cloneImpl() const;

2864public:
/// Constructors - NumReservedClauses is a hint for the number of incoming
/// clauses that this landingpad will have (use 0 if you really have no idea).
static LandingPadInst *Create(Type *RetTy, unsigned NumReservedClauses,
                              const Twine &NameStr = "",
                              Instruction *InsertBefore = nullptr);
static LandingPadInst *Create(Type *RetTy, unsigned NumReservedClauses,
                              const Twine &NameStr, BasicBlock *InsertAtEnd);

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Return 'true' if this landingpad instruction is a
/// cleanup. I.e., it should be run when unwinding even if its landing pad
/// doesn't catch the exception.
bool isCleanup() const { return getSubclassData<CleanupField>(); }

/// Indicate that this landingpad instruction is a cleanup.
void setCleanup(bool V) { setSubclassData<CleanupField>(V); }

/// Add a catch or filter clause to the landing pad.
void addClause(Constant *ClauseVal);

/// Get the value of the clause at index Idx. Use isCatch/isFilter to
/// determine what type of clause this is.
Constant *getClause(unsigned Idx) const {
  return cast<Constant>(getOperandList()[Idx]);
}

/// Return 'true' if the clause and index Idx is a catch clause.
bool isCatch(unsigned Idx) const {
  return !isa<ArrayType>(getOperandList()[Idx]->getType());
}

/// Return 'true' if the clause and index Idx is a filter clause.
bool isFilter(unsigned Idx) const {
  return isa<ArrayType>(getOperandList()[Idx]->getType());
}

/// Get the number of clauses for this landing pad.
unsigned getNumClauses() const { return getNumOperands(); }

/// Grow the size of the operand list to accommodate the new
/// number of clauses.
void reserveClauses(unsigned Size) { growOperands(Size); }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::LandingPad;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
2917};

2919template <>
2920struct OperandTraits<LandingPadInst> : public HungoffOperandTraits<1> {
2921};

2923DEFINE_TRANSPARENT_OPERAND_ACCESSORS(LandingPadInst, Value)LandingPadInst::op_iterator LandingPadInst::op_begin() { return
 OperandTraits<LandingPadInst>::op_begin(this); } LandingPadInst
::const_op_iterator LandingPadInst::op_begin() const { return
 OperandTraits<LandingPadInst>::op_begin(const_cast<
LandingPadInst*>(this)); } LandingPadInst::op_iterator LandingPadInst
::op_end() { return OperandTraits<LandingPadInst>::op_end
(this); } LandingPadInst::const_op_iterator LandingPadInst::op_end
() const { return OperandTraits<LandingPadInst>::op_end
(const_cast<LandingPadInst*>(this)); } Value *LandingPadInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<LandingPadInst>::operands(this) &&
 "getOperand() out of range!") ? static_cast<void> (0) :
 __assert_fail ("i_nocapture < OperandTraits<LandingPadInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2923, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<LandingPadInst>::op_begin(const_cast<
LandingPadInst*>(this))[i_nocapture].get()); } void LandingPadInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
i_nocapture < OperandTraits<LandingPadInst>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<LandingPadInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2923, __PRETTY_FUNCTION__)); OperandTraits<LandingPadInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 LandingPadInst::getNumOperands() const { return OperandTraits
<LandingPadInst>::operands(this); } template <int Idx_nocapture
> Use &LandingPadInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
 const Use &LandingPadInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }

2925//===----------------------------------------------------------------------===//
2926//                               ReturnInst Class
2927//===----------------------------------------------------------------------===//

2929//===---------------------------------------------------------------------------
2930/// Return a value (possibly void), from a function.  Execution
2931/// does not continue in this function any longer.
2932///
2933class ReturnInst : public Instruction {
ReturnInst(const ReturnInst &RI);

2936private:
// ReturnInst constructors:
// ReturnInst()                  - 'ret void' instruction
// ReturnInst(    null)          - 'ret void' instruction
// ReturnInst(Value* X)          - 'ret X'    instruction
// ReturnInst(    null, Inst *I) - 'ret void' instruction, insert before I
// ReturnInst(Value* X, Inst *I) - 'ret X'    instruction, insert before I
// ReturnInst(    null, BB *B)   - 'ret void' instruction, insert @ end of B
// ReturnInst(Value* X, BB *B)   - 'ret X'    instruction, insert @ end of B
//
// NOTE: If the Value* passed is of type void then the constructor behaves as
// if it was passed NULL.
explicit ReturnInst(LLVMContext &C, Value *retVal = nullptr,
                    Instruction *InsertBefore = nullptr);
ReturnInst(LLVMContext &C, Value *retVal, BasicBlock *InsertAtEnd);
explicit ReturnInst(LLVMContext &C, BasicBlock *InsertAtEnd);

2953protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

ReturnInst *cloneImpl() const;

2959public:
static ReturnInst* Create(LLVMContext &C, Value *retVal = nullptr,
                          Instruction *InsertBefore = nullptr) {
  return new(!!retVal) ReturnInst(C, retVal, InsertBefore);
}

static ReturnInst* Create(LLVMContext &C, Value *retVal,
                          BasicBlock *InsertAtEnd) {
  return new(!!retVal) ReturnInst(C, retVal, InsertAtEnd);
}

static ReturnInst* Create(LLVMContext &C, BasicBlock *InsertAtEnd) {
  return new(0) ReturnInst(C, InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Convenience accessor. Returns null if there is no return value.
Value *getReturnValue() const {
  return getNumOperands() != 0 ? getOperand(0) : nullptr;
}

unsigned getNumSuccessors() const { return 0; }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::Ret);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

2992private:
BasicBlock *getSuccessor(unsigned idx) const {
  llvm_unreachable("ReturnInst has no successors!")::llvm::llvm_unreachable_internal("ReturnInst has no successors!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2994);
}

void setSuccessor(unsigned idx, BasicBlock *B) {
  llvm_unreachable("ReturnInst has no successors!")::llvm::llvm_unreachable_internal("ReturnInst has no successors!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 2998);
}
3000};

3002template <>
3003struct OperandTraits<ReturnInst> : public VariadicOperandTraits<ReturnInst> {
3004};

3006DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ReturnInst, Value)ReturnInst::op_iterator ReturnInst::op_begin() { return OperandTraits
<ReturnInst>::op_begin(this); } ReturnInst::const_op_iterator
 ReturnInst::op_begin() const { return OperandTraits<ReturnInst
>::op_begin(const_cast<ReturnInst*>(this)); } ReturnInst
::op_iterator ReturnInst::op_end() { return OperandTraits<
ReturnInst>::op_end(this); } ReturnInst::const_op_iterator
 ReturnInst::op_end() const { return OperandTraits<ReturnInst
>::op_end(const_cast<ReturnInst*>(this)); } Value *ReturnInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<ReturnInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ReturnInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3006, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<ReturnInst>::op_begin(const_cast<ReturnInst
*>(this))[i_nocapture].get()); } void ReturnInst::setOperand
(unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<ReturnInst>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ReturnInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3006, __PRETTY_FUNCTION__)); OperandTraits<ReturnInst>
::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned ReturnInst
::getNumOperands() const { return OperandTraits<ReturnInst
>::operands(this); } template <int Idx_nocapture> Use
 &ReturnInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
ReturnInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }

3008//===----------------------------------------------------------------------===//
3009//                               BranchInst Class
3010//===----------------------------------------------------------------------===//

3012//===---------------------------------------------------------------------------
3013/// Conditional or Unconditional Branch instruction.
3014///
3015class BranchInst : public Instruction {
/// Ops list - Branches are strange.  The operands are ordered:
///  [Cond, FalseDest,] TrueDest.  This makes some accessors faster because
/// they don't have to check for cond/uncond branchness. These are mostly
/// accessed relative from op_end().
BranchInst(const BranchInst &BI);
// BranchInst constructors (where {B, T, F} are blocks, and C is a condition):
// BranchInst(BB *B)                           - 'br B'
// BranchInst(BB* T, BB *F, Value *C)          - 'br C, T, F'
// BranchInst(BB* B, Inst *I)                  - 'br B'        insert before I
// BranchInst(BB* T, BB *F, Value *C, Inst *I) - 'br C, T, F', insert before I
// BranchInst(BB* B, BB *I)                    - 'br B'        insert at end
// BranchInst(BB* T, BB *F, Value *C, BB *I)   - 'br C, T, F', insert at end
explicit BranchInst(BasicBlock *IfTrue, Instruction *InsertBefore = nullptr);
BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
           Instruction *InsertBefore = nullptr);
BranchInst(BasicBlock *IfTrue, BasicBlock *InsertAtEnd);
BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
           BasicBlock *InsertAtEnd);

void AssertOK();

3037protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

BranchInst *cloneImpl() const;

3043public:
/// Iterator type that casts an operand to a basic block.
///
/// This only makes sense because the successors are stored as adjacent
/// operands for branch instructions.
struct succ_op_iterator
    : iterator_adaptor_base<succ_op_iterator, value_op_iterator,
                            std::random_access_iterator_tag, BasicBlock *,
                            ptrdiff_t, BasicBlock *, BasicBlock *> {
  explicit succ_op_iterator(value_op_iterator I) : iterator_adaptor_base(I) {}

  BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
  BasicBlock *operator->() const { return operator*(); }
};

/// The const version of `succ_op_iterator`.
struct const_succ_op_iterator
    : iterator_adaptor_base<const_succ_op_iterator, const_value_op_iterator,
                            std::random_access_iterator_tag,
                            const BasicBlock *, ptrdiff_t, const BasicBlock *,
                            const BasicBlock *> {
  explicit const_succ_op_iterator(const_value_op_iterator I)
      : iterator_adaptor_base(I) {}

  const BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
  const BasicBlock *operator->() const { return operator*(); }
};

static BranchInst *Create(BasicBlock *IfTrue,
                          Instruction *InsertBefore = nullptr) {
  return new(1) BranchInst(IfTrue, InsertBefore);
}

static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *IfFalse,
                          Value *Cond, Instruction *InsertBefore = nullptr) {
  return new(3) BranchInst(IfTrue, IfFalse, Cond, InsertBefore);
}

static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *InsertAtEnd) {
  return new(1) BranchInst(IfTrue, InsertAtEnd);
}

static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *IfFalse,
                          Value *Cond, BasicBlock *InsertAtEnd) {
  return new(3) BranchInst(IfTrue, IfFalse, Cond, InsertAtEnd);
}

/// Transparently provide more efficient getOperand methods.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

bool isUnconditional() const { return getNumOperands() == 1; }
43
←
Assuming the condition is false→
44
←
Returning zero, which participates in a condition later→
bool isConditional()   const { return getNumOperands() == 3; }
4
←
Assuming the condition is true→
5
←
Returning the value 1, which participates in a condition later→
47
←
Returning the value 1, which participates in a condition later→
55
←
Returning the value 1, which participates in a condition later→
58
←
Returning the value 1, which participates in a condition later→
71
←
Returning the value 1, which participates in a condition later→

Value *getCondition() const {
  assert(isConditional() && "Cannot get condition of an uncond branch!")((isConditional() && "Cannot get condition of an uncond branch!"
) ? static_cast<void> (0) : __assert_fail ("isConditional() && \"Cannot get condition of an uncond branch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3097, __PRETTY_FUNCTION__));
  return Op<-3>();
}

void setCondition(Value *V) {
  assert(isConditional() && "Cannot set condition of unconditional branch!")((isConditional() && "Cannot set condition of unconditional branch!"
) ? static_cast<void> (0) : __assert_fail ("isConditional() && \"Cannot set condition of unconditional branch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3102, __PRETTY_FUNCTION__));
  Op<-3>() = V;
}

unsigned getNumSuccessors() const { return 1+isConditional(); }

BasicBlock *getSuccessor(unsigned i) const {
  assert(i < getNumSuccessors() && "Successor # out of range for Branch!")((i < getNumSuccessors() && "Successor # out of range for Branch!"
) ? static_cast<void> (0) : __assert_fail ("i < getNumSuccessors() && \"Successor # out of range for Branch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3109, __PRETTY_FUNCTION__));
  return cast_or_null<BasicBlock>((&Op<-1>() - i)->get());
}

void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
  assert(idx < getNumSuccessors() && "Successor # out of range for Branch!")((idx < getNumSuccessors() && "Successor # out of range for Branch!"
) ? static_cast<void> (0) : __assert_fail ("idx < getNumSuccessors() && \"Successor # out of range for Branch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3114, __PRETTY_FUNCTION__));
  *(&Op<-1>() - idx) = NewSucc;
}

/// Swap the successors of this branch instruction.
///
/// Swaps the successors of the branch instruction. This also swaps any
/// branch weight metadata associated with the instruction so that it
/// continues to map correctly to each operand.
void swapSuccessors();

iterator_range<succ_op_iterator> successors() {
  return make_range(
      succ_op_iterator(std::next(value_op_begin(), isConditional() ? 1 : 0)),
      succ_op_iterator(value_op_end()));
}

iterator_range<const_succ_op_iterator> successors() const {
  return make_range(const_succ_op_iterator(
                        std::next(value_op_begin(), isConditional() ? 1 : 0)),
                    const_succ_op_iterator(value_op_end()));
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::Br);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
3144};

3146template <>
3147struct OperandTraits<BranchInst> : public VariadicOperandTraits<BranchInst, 1> {
3148};

3150DEFINE_TRANSPARENT_OPERAND_ACCESSORS(BranchInst, Value)BranchInst::op_iterator BranchInst::op_begin() { return OperandTraits
<BranchInst>::op_begin(this); } BranchInst::const_op_iterator
 BranchInst::op_begin() const { return OperandTraits<BranchInst
>::op_begin(const_cast<BranchInst*>(this)); } BranchInst
::op_iterator BranchInst::op_end() { return OperandTraits<
BranchInst>::op_end(this); } BranchInst::const_op_iterator
 BranchInst::op_end() const { return OperandTraits<BranchInst
>::op_end(const_cast<BranchInst*>(this)); } Value *BranchInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<BranchInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<BranchInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3150, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<BranchInst>::op_begin(const_cast<BranchInst
*>(this))[i_nocapture].get()); } void BranchInst::setOperand
(unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<BranchInst>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<BranchInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3150, __PRETTY_FUNCTION__)); OperandTraits<BranchInst>
::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned BranchInst
::getNumOperands() const { return OperandTraits<BranchInst
>::operands(this); } template <int Idx_nocapture> Use
 &BranchInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
BranchInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }

3152//===----------------------------------------------------------------------===//
3153//                               SwitchInst Class
3154//===----------------------------------------------------------------------===//

3156//===---------------------------------------------------------------------------
3157/// Multiway switch
3158///
3159class SwitchInst : public Instruction {
unsigned ReservedSpace;

// Operand[0]    = Value to switch on
// Operand[1]    = Default basic block destination
// Operand[2n  ] = Value to match
// Operand[2n+1] = BasicBlock to go to on match
SwitchInst(const SwitchInst &SI);

/// Create a new switch instruction, specifying a value to switch on and a
/// default destination. The number of additional cases can be specified here
/// to make memory allocation more efficient. This constructor can also
/// auto-insert before another instruction.
SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
           Instruction *InsertBefore);

/// Create a new switch instruction, specifying a value to switch on and a
/// default destination. The number of additional cases can be specified here
/// to make memory allocation more efficient. This constructor also
/// auto-inserts at the end of the specified BasicBlock.
SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
           BasicBlock *InsertAtEnd);

// allocate space for exactly zero operands
void *operator new(size_t s) {
  return User::operator new(s);
}

void init(Value *Value, BasicBlock *Default, unsigned NumReserved);
void growOperands();

3190protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

SwitchInst *cloneImpl() const;

3196public:
// -2
static const unsigned DefaultPseudoIndex = static_cast<unsigned>(~0L-1);

template <typename CaseHandleT> class CaseIteratorImpl;

/// A handle to a particular switch case. It exposes a convenient interface
/// to both the case value and the successor block.
///
/// We define this as a template and instantiate it to form both a const and
/// non-const handle.
template <typename SwitchInstT, typename ConstantIntT, typename BasicBlockT>
class CaseHandleImpl {
  // Directly befriend both const and non-const iterators.
  friend class SwitchInst::CaseIteratorImpl<
      CaseHandleImpl<SwitchInstT, ConstantIntT, BasicBlockT>>;

protected:
  // Expose the switch type we're parameterized with to the iterator.
  using SwitchInstType = SwitchInstT;

  SwitchInstT *SI;
  ptrdiff_t Index;

  CaseHandleImpl() = default;
  CaseHandleImpl(SwitchInstT *SI, ptrdiff_t Index) : SI(SI), Index(Index) {}

public:
  /// Resolves case value for current case.
  ConstantIntT *getCaseValue() const {
    assert((unsigned)Index < SI->getNumCases() &&(((unsigned)Index < SI->getNumCases() && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("(unsigned)Index < SI->getNumCases() && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3227, __PRETTY_FUNCTION__))
           "Index out the number of cases.")(((unsigned)Index < SI->getNumCases() && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("(unsigned)Index < SI->getNumCases() && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3227, __PRETTY_FUNCTION__));
    return reinterpret_cast<ConstantIntT *>(SI->getOperand(2 + Index * 2));
  }

  /// Resolves successor for current case.
  BasicBlockT *getCaseSuccessor() const {
    assert(((unsigned)Index < SI->getNumCases() ||((((unsigned)Index < SI->getNumCases() || (unsigned)Index
 == DefaultPseudoIndex) && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("((unsigned)Index < SI->getNumCases() || (unsigned)Index == DefaultPseudoIndex) && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3235, __PRETTY_FUNCTION__))
            (unsigned)Index == DefaultPseudoIndex) &&((((unsigned)Index < SI->getNumCases() || (unsigned)Index
 == DefaultPseudoIndex) && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("((unsigned)Index < SI->getNumCases() || (unsigned)Index == DefaultPseudoIndex) && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3235, __PRETTY_FUNCTION__))
           "Index out the number of cases.")((((unsigned)Index < SI->getNumCases() || (unsigned)Index
 == DefaultPseudoIndex) && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("((unsigned)Index < SI->getNumCases() || (unsigned)Index == DefaultPseudoIndex) && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3235, __PRETTY_FUNCTION__));
    return SI->getSuccessor(getSuccessorIndex());
  }

  /// Returns number of current case.
  unsigned getCaseIndex() const { return Index; }

  /// Returns successor index for current case successor.
  unsigned getSuccessorIndex() const {
    assert(((unsigned)Index == DefaultPseudoIndex ||((((unsigned)Index == DefaultPseudoIndex || (unsigned)Index <
 SI->getNumCases()) && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("((unsigned)Index == DefaultPseudoIndex || (unsigned)Index < SI->getNumCases()) && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3246, __PRETTY_FUNCTION__))
            (unsigned)Index < SI->getNumCases()) &&((((unsigned)Index == DefaultPseudoIndex || (unsigned)Index <
 SI->getNumCases()) && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("((unsigned)Index == DefaultPseudoIndex || (unsigned)Index < SI->getNumCases()) && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3246, __PRETTY_FUNCTION__))
           "Index out the number of cases.")((((unsigned)Index == DefaultPseudoIndex || (unsigned)Index <
 SI->getNumCases()) && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("((unsigned)Index == DefaultPseudoIndex || (unsigned)Index < SI->getNumCases()) && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3246, __PRETTY_FUNCTION__));
    return (unsigned)Index != DefaultPseudoIndex ? Index + 1 : 0;
  }

  bool operator==(const CaseHandleImpl &RHS) const {
    assert(SI == RHS.SI && "Incompatible operators.")((SI == RHS.SI && "Incompatible operators.") ? static_cast
<void> (0) : __assert_fail ("SI == RHS.SI && \"Incompatible operators.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3251, __PRETTY_FUNCTION__));
    return Index == RHS.Index;
  }
};

using ConstCaseHandle =
    CaseHandleImpl<const SwitchInst, const ConstantInt, const BasicBlock>;

class CaseHandle
    : public CaseHandleImpl<SwitchInst, ConstantInt, BasicBlock> {
  friend class SwitchInst::CaseIteratorImpl<CaseHandle>;

public:
  CaseHandle(SwitchInst *SI, ptrdiff_t Index) : CaseHandleImpl(SI, Index) {}

  /// Sets the new value for current case.
  void setValue(ConstantInt *V) {
    assert((unsigned)Index < SI->getNumCases() &&(((unsigned)Index < SI->getNumCases() && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("(unsigned)Index < SI->getNumCases() && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3269, __PRETTY_FUNCTION__))
           "Index out the number of cases.")(((unsigned)Index < SI->getNumCases() && "Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("(unsigned)Index < SI->getNumCases() && \"Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3269, __PRETTY_FUNCTION__));
    SI->setOperand(2 + Index*2, reinterpret_cast<Value*>(V));
  }

  /// Sets the new successor for current case.
  void setSuccessor(BasicBlock *S) {
    SI->setSuccessor(getSuccessorIndex(), S);
  }
};

template <typename CaseHandleT>
class CaseIteratorImpl
    : public iterator_facade_base<CaseIteratorImpl<CaseHandleT>,
                                  std::random_access_iterator_tag,
                                  CaseHandleT> {
  using SwitchInstT = typename CaseHandleT::SwitchInstType;

  CaseHandleT Case;

public:
  /// Default constructed iterator is in an invalid state until assigned to
  /// a case for a particular switch.
  CaseIteratorImpl() = default;

  /// Initializes case iterator for given SwitchInst and for given
  /// case number.
  CaseIteratorImpl(SwitchInstT *SI, unsigned CaseNum) : Case(SI, CaseNum) {}

  /// Initializes case iterator for given SwitchInst and for given
  /// successor index.
  static CaseIteratorImpl fromSuccessorIndex(SwitchInstT *SI,
                                             unsigned SuccessorIndex) {
    assert(SuccessorIndex < SI->getNumSuccessors() &&((SuccessorIndex < SI->getNumSuccessors() && "Successor index # out of range!"
) ? static_cast<void> (0) : __assert_fail ("SuccessorIndex < SI->getNumSuccessors() && \"Successor index # out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3302, __PRETTY_FUNCTION__))
           "Successor index # out of range!")((SuccessorIndex < SI->getNumSuccessors() && "Successor index # out of range!"
) ? static_cast<void> (0) : __assert_fail ("SuccessorIndex < SI->getNumSuccessors() && \"Successor index # out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3302, __PRETTY_FUNCTION__));
    return SuccessorIndex != 0 ? CaseIteratorImpl(SI, SuccessorIndex - 1)
                               : CaseIteratorImpl(SI, DefaultPseudoIndex);
  }

  /// Support converting to the const variant. This will be a no-op for const
  /// variant.
  operator CaseIteratorImpl<ConstCaseHandle>() const {
    return CaseIteratorImpl<ConstCaseHandle>(Case.SI, Case.Index);
  }

  CaseIteratorImpl &operator+=(ptrdiff_t N) {
    // Check index correctness after addition.
    // Note: Index == getNumCases() means end().
    assert(Case.Index + N >= 0 &&((Case.Index + N >= 0 && (unsigned)(Case.Index + N
) <= Case.SI->getNumCases() && "Case.Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("Case.Index + N >= 0 && (unsigned)(Case.Index + N) <= Case.SI->getNumCases() && \"Case.Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3318, __PRETTY_FUNCTION__))
           (unsigned)(Case.Index + N) <= Case.SI->getNumCases() &&((Case.Index + N >= 0 && (unsigned)(Case.Index + N
) <= Case.SI->getNumCases() && "Case.Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("Case.Index + N >= 0 && (unsigned)(Case.Index + N) <= Case.SI->getNumCases() && \"Case.Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3318, __PRETTY_FUNCTION__))
           "Case.Index out the number of cases.")((Case.Index + N >= 0 && (unsigned)(Case.Index + N
) <= Case.SI->getNumCases() && "Case.Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("Case.Index + N >= 0 && (unsigned)(Case.Index + N) <= Case.SI->getNumCases() && \"Case.Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3318, __PRETTY_FUNCTION__));
    Case.Index += N;
    return *this;
  }
  CaseIteratorImpl &operator-=(ptrdiff_t N) {
    // Check index correctness after subtraction.
    // Note: Case.Index == getNumCases() means end().
    assert(Case.Index - N >= 0 &&((Case.Index - N >= 0 && (unsigned)(Case.Index - N
) <= Case.SI->getNumCases() && "Case.Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("Case.Index - N >= 0 && (unsigned)(Case.Index - N) <= Case.SI->getNumCases() && \"Case.Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3327, __PRETTY_FUNCTION__))
           (unsigned)(Case.Index - N) <= Case.SI->getNumCases() &&((Case.Index - N >= 0 && (unsigned)(Case.Index - N
) <= Case.SI->getNumCases() && "Case.Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("Case.Index - N >= 0 && (unsigned)(Case.Index - N) <= Case.SI->getNumCases() && \"Case.Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3327, __PRETTY_FUNCTION__))
           "Case.Index out the number of cases.")((Case.Index - N >= 0 && (unsigned)(Case.Index - N
) <= Case.SI->getNumCases() && "Case.Index out the number of cases."
) ? static_cast<void> (0) : __assert_fail ("Case.Index - N >= 0 && (unsigned)(Case.Index - N) <= Case.SI->getNumCases() && \"Case.Index out the number of cases.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3327, __PRETTY_FUNCTION__));
    Case.Index -= N;
    return *this;
  }
  ptrdiff_t operator-(const CaseIteratorImpl &RHS) const {
    assert(Case.SI == RHS.Case.SI && "Incompatible operators.")((Case.SI == RHS.Case.SI && "Incompatible operators."
) ? static_cast<void> (0) : __assert_fail ("Case.SI == RHS.Case.SI && \"Incompatible operators.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3332, __PRETTY_FUNCTION__));
    return Case.Index - RHS.Case.Index;
  }
  bool operator==(const CaseIteratorImpl &RHS) const {
    return Case == RHS.Case;
  }
  bool operator<(const CaseIteratorImpl &RHS) const {
    assert(Case.SI == RHS.Case.SI && "Incompatible operators.")((Case.SI == RHS.Case.SI && "Incompatible operators."
) ? static_cast<void> (0) : __assert_fail ("Case.SI == RHS.Case.SI && \"Incompatible operators.\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3339, __PRETTY_FUNCTION__));
    return Case.Index < RHS.Case.Index;
  }
  CaseHandleT &operator*() { return Case; }
  const CaseHandleT &operator*() const { return Case; }
};

using CaseIt = CaseIteratorImpl<CaseHandle>;
using ConstCaseIt = CaseIteratorImpl<ConstCaseHandle>;

static SwitchInst *Create(Value *Value, BasicBlock *Default,
                          unsigned NumCases,
                          Instruction *InsertBefore = nullptr) {
  return new SwitchInst(Value, Default, NumCases, InsertBefore);
}

static SwitchInst *Create(Value *Value, BasicBlock *Default,
                          unsigned NumCases, BasicBlock *InsertAtEnd) {
  return new SwitchInst(Value, Default, NumCases, InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

// Accessor Methods for Switch stmt
Value *getCondition() const { return getOperand(0); }
void setCondition(Value *V) { setOperand(0, V); }

BasicBlock *getDefaultDest() const {
  return cast<BasicBlock>(getOperand(1));
}

void setDefaultDest(BasicBlock *DefaultCase) {
  setOperand(1, reinterpret_cast<Value*>(DefaultCase));
}

/// Return the number of 'cases' in this switch instruction, excluding the
/// default case.
unsigned getNumCases() const {
  return getNumOperands()/2 - 1;
}

/// Returns a read/write iterator that points to the first case in the
/// SwitchInst.
CaseIt case_begin() {
  return CaseIt(this, 0);
}

/// Returns a read-only iterator that points to the first case in the
/// SwitchInst.
ConstCaseIt case_begin() const {
  return ConstCaseIt(this, 0);
}

/// Returns a read/write iterator that points one past the last in the
/// SwitchInst.
CaseIt case_end() {
  return CaseIt(this, getNumCases());
}

/// Returns a read-only iterator that points one past the last in the
/// SwitchInst.
ConstCaseIt case_end() const {
  return ConstCaseIt(this, getNumCases());
}

/// Iteration adapter for range-for loops.
iterator_range<CaseIt> cases() {
  return make_range(case_begin(), case_end());
}

/// Constant iteration adapter for range-for loops.
iterator_range<ConstCaseIt> cases() const {
  return make_range(case_begin(), case_end());
}

/// Returns an iterator that points to the default case.
/// Note: this iterator allows to resolve successor only. Attempt
/// to resolve case value causes an assertion.
/// Also note, that increment and decrement also causes an assertion and
/// makes iterator invalid.
CaseIt case_default() {
  return CaseIt(this, DefaultPseudoIndex);
}
ConstCaseIt case_default() const {
  return ConstCaseIt(this, DefaultPseudoIndex);
}

/// Search all of the case values for the specified constant. If it is
/// explicitly handled, return the case iterator of it, otherwise return
/// default case iterator to indicate that it is handled by the default
/// handler.
CaseIt findCaseValue(const ConstantInt *C) {
  CaseIt I = llvm::find_if(
      cases(), [C](CaseHandle &Case) { return Case.getCaseValue() == C; });
  if (I != case_end())
    return I;

  return case_default();
}
ConstCaseIt findCaseValue(const ConstantInt *C) const {
  ConstCaseIt I = llvm::find_if(cases(), [C](ConstCaseHandle &Case) {
    return Case.getCaseValue() == C;
  });
  if (I != case_end())
    return I;

  return case_default();
}

/// Finds the unique case value for a given successor. Returns null if the
/// successor is not found, not unique, or is the default case.
ConstantInt *findCaseDest(BasicBlock *BB) {
  if (BB == getDefaultDest())
    return nullptr;

  ConstantInt *CI = nullptr;
  for (auto Case : cases()) {
    if (Case.getCaseSuccessor() != BB)
      continue;

    if (CI)
      return nullptr; // Multiple cases lead to BB.

    CI = Case.getCaseValue();
  }

  return CI;
}

/// Add an entry to the switch instruction.
/// Note:
/// This action invalidates case_end(). Old case_end() iterator will
/// point to the added case.
void addCase(ConstantInt *OnVal, BasicBlock *Dest);

/// This method removes the specified case and its successor from the switch
/// instruction. Note that this operation may reorder the remaining cases at
/// index idx and above.
/// Note:
/// This action invalidates iterators for all cases following the one removed,
/// including the case_end() iterator. It returns an iterator for the next
/// case.
CaseIt removeCase(CaseIt I);

unsigned getNumSuccessors() const { return getNumOperands()/2; }
BasicBlock *getSuccessor(unsigned idx) const {
  assert(idx < getNumSuccessors() &&"Successor idx out of range for switch!")((idx < getNumSuccessors() &&"Successor idx out of range for switch!"
) ? static_cast<void> (0) : __assert_fail ("idx < getNumSuccessors() &&\"Successor idx out of range for switch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3486, __PRETTY_FUNCTION__));
  return cast<BasicBlock>(getOperand(idx*2+1));
}
void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
  assert(idx < getNumSuccessors() && "Successor # out of range for switch!")((idx < getNumSuccessors() && "Successor # out of range for switch!"
) ? static_cast<void> (0) : __assert_fail ("idx < getNumSuccessors() && \"Successor # out of range for switch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3490, __PRETTY_FUNCTION__));
  setOperand(idx * 2 + 1, NewSucc);
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Switch;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
3501};

3503/// A wrapper class to simplify modification of SwitchInst cases along with
3504/// their prof branch_weights metadata.
3505class SwitchInstProfUpdateWrapper {
SwitchInst &SI;
Optional<SmallVector<uint32_t, 8> > Weights = None;
bool Changed = false;

3510protected:
static MDNode *getProfBranchWeightsMD(const SwitchInst &SI);

MDNode *buildProfBranchWeightsMD();

void init();

3517public:
using CaseWeightOpt = Optional<uint32_t>;
SwitchInst *operator->() { return &SI; }
SwitchInst &operator*() { return SI; }
operator SwitchInst *() { return &SI; }

SwitchInstProfUpdateWrapper(SwitchInst &SI) : SI(SI) { init(); }

~SwitchInstProfUpdateWrapper() {
  if (Changed)
    SI.setMetadata(LLVMContext::MD_prof, buildProfBranchWeightsMD());
}

/// Delegate the call to the underlying SwitchInst::removeCase() and remove
/// correspondent branch weight.
SwitchInst::CaseIt removeCase(SwitchInst::CaseIt I);

/// Delegate the call to the underlying SwitchInst::addCase() and set the
/// specified branch weight for the added case.
void addCase(ConstantInt *OnVal, BasicBlock *Dest, CaseWeightOpt W);

/// Delegate the call to the underlying SwitchInst::eraseFromParent() and mark
/// this object to not touch the underlying SwitchInst in destructor.
SymbolTableList<Instruction>::iterator eraseFromParent();

void setSuccessorWeight(unsigned idx, CaseWeightOpt W);
CaseWeightOpt getSuccessorWeight(unsigned idx);

static CaseWeightOpt getSuccessorWeight(const SwitchInst &SI, unsigned idx);
3546};

3548template <>
3549struct OperandTraits<SwitchInst> : public HungoffOperandTraits<2> {
3550};

3552DEFINE_TRANSPARENT_OPERAND_ACCESSORS(SwitchInst, Value)SwitchInst::op_iterator SwitchInst::op_begin() { return OperandTraits
<SwitchInst>::op_begin(this); } SwitchInst::const_op_iterator
 SwitchInst::op_begin() const { return OperandTraits<SwitchInst
>::op_begin(const_cast<SwitchInst*>(this)); } SwitchInst
::op_iterator SwitchInst::op_end() { return OperandTraits<
SwitchInst>::op_end(this); } SwitchInst::const_op_iterator
 SwitchInst::op_end() const { return OperandTraits<SwitchInst
>::op_end(const_cast<SwitchInst*>(this)); } Value *SwitchInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<SwitchInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<SwitchInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3552, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<SwitchInst>::op_begin(const_cast<SwitchInst
*>(this))[i_nocapture].get()); } void SwitchInst::setOperand
(unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<SwitchInst>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<SwitchInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3552, __PRETTY_FUNCTION__)); OperandTraits<SwitchInst>
::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned SwitchInst
::getNumOperands() const { return OperandTraits<SwitchInst
>::operands(this); } template <int Idx_nocapture> Use
 &SwitchInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
SwitchInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }

3554//===----------------------------------------------------------------------===//
3555//                             IndirectBrInst Class
3556//===----------------------------------------------------------------------===//

3558//===---------------------------------------------------------------------------
3559/// Indirect Branch Instruction.
3560///
3561class IndirectBrInst : public Instruction {
unsigned ReservedSpace;

// Operand[0]   = Address to jump to
// Operand[n+1] = n-th destination
IndirectBrInst(const IndirectBrInst &IBI);

/// Create a new indirectbr instruction, specifying an
/// Address to jump to.  The number of expected destinations can be specified
/// here to make memory allocation more efficient.  This constructor can also
/// autoinsert before another instruction.
IndirectBrInst(Value *Address, unsigned NumDests, Instruction *InsertBefore);

/// Create a new indirectbr instruction, specifying an
/// Address to jump to.  The number of expected destinations can be specified
/// here to make memory allocation more efficient.  This constructor also
/// autoinserts at the end of the specified BasicBlock.
IndirectBrInst(Value *Address, unsigned NumDests, BasicBlock *InsertAtEnd);

// allocate space for exactly zero operands
void *operator new(size_t s) {
  return User::operator new(s);
}

void init(Value *Address, unsigned NumDests);
void growOperands();

3588protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

IndirectBrInst *cloneImpl() const;

3594public:
/// Iterator type that casts an operand to a basic block.
///
/// This only makes sense because the successors are stored as adjacent
/// operands for indirectbr instructions.
struct succ_op_iterator
    : iterator_adaptor_base<succ_op_iterator, value_op_iterator,
                            std::random_access_iterator_tag, BasicBlock *,
                            ptrdiff_t, BasicBlock *, BasicBlock *> {
  explicit succ_op_iterator(value_op_iterator I) : iterator_adaptor_base(I) {}

  BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
  BasicBlock *operator->() const { return operator*(); }
};

/// The const version of `succ_op_iterator`.
struct const_succ_op_iterator
    : iterator_adaptor_base<const_succ_op_iterator, const_value_op_iterator,
                            std::random_access_iterator_tag,
                            const BasicBlock *, ptrdiff_t, const BasicBlock *,
                            const BasicBlock *> {
  explicit const_succ_op_iterator(const_value_op_iterator I)
      : iterator_adaptor_base(I) {}

  const BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
  const BasicBlock *operator->() const { return operator*(); }
};

static IndirectBrInst *Create(Value *Address, unsigned NumDests,
                              Instruction *InsertBefore = nullptr) {
  return new IndirectBrInst(Address, NumDests, InsertBefore);
}

static IndirectBrInst *Create(Value *Address, unsigned NumDests,
                              BasicBlock *InsertAtEnd) {
  return new IndirectBrInst(Address, NumDests, InsertAtEnd);
}

/// Provide fast operand accessors.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

// Accessor Methods for IndirectBrInst instruction.
Value *getAddress() { return getOperand(0); }
const Value *getAddress() const { return getOperand(0); }
void setAddress(Value *V) { setOperand(0, V); }

/// return the number of possible destinations in this
/// indirectbr instruction.
unsigned getNumDestinations() const { return getNumOperands()-1; }

/// Return the specified destination.
BasicBlock *getDestination(unsigned i) { return getSuccessor(i); }
const BasicBlock *getDestination(unsigned i) const { return getSuccessor(i); }

/// Add a destination.
///
void addDestination(BasicBlock *Dest);

/// This method removes the specified successor from the
/// indirectbr instruction.
void removeDestination(unsigned i);

unsigned getNumSuccessors() const { return getNumOperands()-1; }
BasicBlock *getSuccessor(unsigned i) const {
  return cast<BasicBlock>(getOperand(i+1));
}
void setSuccessor(unsigned i, BasicBlock *NewSucc) {
  setOperand(i + 1, NewSucc);
}

iterator_range<succ_op_iterator> successors() {
  return make_range(succ_op_iterator(std::next(value_op_begin())),
                    succ_op_iterator(value_op_end()));
}

iterator_range<const_succ_op_iterator> successors() const {
  return make_range(const_succ_op_iterator(std::next(value_op_begin())),
                    const_succ_op_iterator(value_op_end()));
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::IndirectBr;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
3681};

3683template <>
3684struct OperandTraits<IndirectBrInst> : public HungoffOperandTraits<1> {
3685};

3687DEFINE_TRANSPARENT_OPERAND_ACCESSORS(IndirectBrInst, Value)IndirectBrInst::op_iterator IndirectBrInst::op_begin() { return
 OperandTraits<IndirectBrInst>::op_begin(this); } IndirectBrInst
::const_op_iterator IndirectBrInst::op_begin() const { return
 OperandTraits<IndirectBrInst>::op_begin(const_cast<
IndirectBrInst*>(this)); } IndirectBrInst::op_iterator IndirectBrInst
::op_end() { return OperandTraits<IndirectBrInst>::op_end
(this); } IndirectBrInst::const_op_iterator IndirectBrInst::op_end
() const { return OperandTraits<IndirectBrInst>::op_end
(const_cast<IndirectBrInst*>(this)); } Value *IndirectBrInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<IndirectBrInst>::operands(this) &&
 "getOperand() out of range!") ? static_cast<void> (0) :
 __assert_fail ("i_nocapture < OperandTraits<IndirectBrInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3687, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<IndirectBrInst>::op_begin(const_cast<
IndirectBrInst*>(this))[i_nocapture].get()); } void IndirectBrInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
i_nocapture < OperandTraits<IndirectBrInst>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<IndirectBrInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3687, __PRETTY_FUNCTION__)); OperandTraits<IndirectBrInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 IndirectBrInst::getNumOperands() const { return OperandTraits
<IndirectBrInst>::operands(this); } template <int Idx_nocapture
> Use &IndirectBrInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
 const Use &IndirectBrInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }

3689//===----------------------------------------------------------------------===//
3690//                               InvokeInst Class
3691//===----------------------------------------------------------------------===//

3693/// Invoke instruction.  The SubclassData field is used to hold the
3694/// calling convention of the call.
3695///
3696class InvokeInst : public CallBase {
/// The number of operands for this call beyond the called function,
/// arguments, and operand bundles.
static constexpr int NumExtraOperands = 2;

/// The index from the end of the operand array to the normal destination.
static constexpr int NormalDestOpEndIdx = -3;

/// The index from the end of the operand array to the unwind destination.
static constexpr int UnwindDestOpEndIdx = -2;

InvokeInst(const InvokeInst &BI);

/// Construct an InvokeInst given a range of arguments.
///
/// Construct an InvokeInst from a range of arguments
inline InvokeInst(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                  BasicBlock *IfException, ArrayRef<Value *> Args,
                  ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                  const Twine &NameStr, Instruction *InsertBefore);

inline InvokeInst(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                  BasicBlock *IfException, ArrayRef<Value *> Args,
                  ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                  const Twine &NameStr, BasicBlock *InsertAtEnd);

void init(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
          BasicBlock *IfException, ArrayRef<Value *> Args,
          ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);

/// Compute the number of operands to allocate.
static int ComputeNumOperands(int NumArgs, int NumBundleInputs = 0) {
  // We need one operand for the called function, plus our extra operands and
  // the input operand counts provided.
  return 1 + NumExtraOperands + NumArgs + NumBundleInputs;
}

3733protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

InvokeInst *cloneImpl() const;

3739public:
static InvokeInst *Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          const Twine &NameStr,
                          Instruction *InsertBefore = nullptr) {
  int NumOperands = ComputeNumOperands(Args.size());
  return new (NumOperands)
      InvokeInst(Ty, Func, IfNormal, IfException, Args, None, NumOperands,
                 NameStr, InsertBefore);
}

static InvokeInst *Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles = None,
                          const Twine &NameStr = "",
                          Instruction *InsertBefore = nullptr) {
  int NumOperands =
      ComputeNumOperands(Args.size(), CountBundleInputs(Bundles));
  unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);

  return new (NumOperands, DescriptorBytes)
      InvokeInst(Ty, Func, IfNormal, IfException, Args, Bundles, NumOperands,
                 NameStr, InsertBefore);
}

static InvokeInst *Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          const Twine &NameStr, BasicBlock *InsertAtEnd) {
  int NumOperands = ComputeNumOperands(Args.size());
  return new (NumOperands)
      InvokeInst(Ty, Func, IfNormal, IfException, Args, None, NumOperands,
                 NameStr, InsertAtEnd);
}

static InvokeInst *Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles,
                          const Twine &NameStr, BasicBlock *InsertAtEnd) {
  int NumOperands =
      ComputeNumOperands(Args.size(), CountBundleInputs(Bundles));
  unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);

  return new (NumOperands, DescriptorBytes)
      InvokeInst(Ty, Func, IfNormal, IfException, Args, Bundles, NumOperands,
                 NameStr, InsertAtEnd);
}

static InvokeInst *Create(FunctionCallee Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          const Twine &NameStr,
                          Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), IfNormal,
                IfException, Args, None, NameStr, InsertBefore);
}

static InvokeInst *Create(FunctionCallee Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles = None,
                          const Twine &NameStr = "",
                          Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), IfNormal,
                IfException, Args, Bundles, NameStr, InsertBefore);
}

static InvokeInst *Create(FunctionCallee Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), IfNormal,
                IfException, Args, NameStr, InsertAtEnd);
}

static InvokeInst *Create(FunctionCallee Func, BasicBlock *IfNormal,
                          BasicBlock *IfException, ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles,
                          const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), IfNormal,
                IfException, Args, Bundles, NameStr, InsertAtEnd);
}

/// Create a clone of \p II with a different set of operand bundles and
/// insert it before \p InsertPt.
///
/// The returned invoke instruction is identical to \p II in every way except
/// that the operand bundles for the new instruction are set to the operand
/// bundles in \p Bundles.
static InvokeInst *Create(InvokeInst *II, ArrayRef<OperandBundleDef> Bundles,
                          Instruction *InsertPt = nullptr);

/// Create a clone of \p II with a different set of operand bundles and
/// insert it before \p InsertPt.
///
/// The returned invoke instruction is identical to \p II in every way except
/// that the operand bundle for the new instruction is set to the operand
/// bundle in \p Bundle.
static InvokeInst *CreateWithReplacedBundle(InvokeInst *II,
                                            OperandBundleDef Bundles,
                                            Instruction *InsertPt = nullptr);

// get*Dest - Return the destination basic blocks...
BasicBlock *getNormalDest() const {
  return cast<BasicBlock>(Op<NormalDestOpEndIdx>());
}
BasicBlock *getUnwindDest() const {
  return cast<BasicBlock>(Op<UnwindDestOpEndIdx>());
}
void setNormalDest(BasicBlock *B) {
  Op<NormalDestOpEndIdx>() = reinterpret_cast<Value *>(B);
}
void setUnwindDest(BasicBlock *B) {
  Op<UnwindDestOpEndIdx>() = reinterpret_cast<Value *>(B);
}

/// Get the landingpad instruction from the landing pad
/// block (the unwind destination).
LandingPadInst *getLandingPadInst() const;

BasicBlock *getSuccessor(unsigned i) const {
  assert(i < 2 && "Successor # out of range for invoke!")((i < 2 && "Successor # out of range for invoke!")
 ? static_cast<void> (0) : __assert_fail ("i < 2 && \"Successor # out of range for invoke!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3856, __PRETTY_FUNCTION__));
  return i == 0 ? getNormalDest() : getUnwindDest();
}

void setSuccessor(unsigned i, BasicBlock *NewSucc) {
  assert(i < 2 && "Successor # out of range for invoke!")((i < 2 && "Successor # out of range for invoke!")
 ? static_cast<void> (0) : __assert_fail ("i < 2 && \"Successor # out of range for invoke!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 3861, __PRETTY_FUNCTION__));
  if (i == 0)
    setNormalDest(NewSucc);
  else
    setUnwindDest(NewSucc);
}

unsigned getNumSuccessors() const { return 2; }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::Invoke);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

3878private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}
3885};

3887InvokeInst::InvokeInst(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                     BasicBlock *IfException, ArrayRef<Value *> Args,
                     ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                     const Twine &NameStr, Instruction *InsertBefore)
  : CallBase(Ty->getReturnType(), Instruction::Invoke,
             OperandTraits<CallBase>::op_end(this) - NumOperands, NumOperands,
             InsertBefore) {
init(Ty, Func, IfNormal, IfException, Args, Bundles, NameStr);
3895}

3897InvokeInst::InvokeInst(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                     BasicBlock *IfException, ArrayRef<Value *> Args,
                     ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                     const Twine &NameStr, BasicBlock *InsertAtEnd)
  : CallBase(Ty->getReturnType(), Instruction::Invoke,
             OperandTraits<CallBase>::op_end(this) - NumOperands, NumOperands,
             InsertAtEnd) {
init(Ty, Func, IfNormal, IfException, Args, Bundles, NameStr);
3905}

3907//===----------------------------------------------------------------------===//
3908//                              CallBrInst Class
3909//===----------------------------------------------------------------------===//

3911/// CallBr instruction, tracking function calls that may not return control but
3912/// instead transfer it to a third location. The SubclassData field is used to
3913/// hold the calling convention of the call.
3914///
3915class CallBrInst : public CallBase {

unsigned NumIndirectDests;

CallBrInst(const CallBrInst &BI);

/// Construct a CallBrInst given a range of arguments.
///
/// Construct a CallBrInst from a range of arguments
inline CallBrInst(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
                  ArrayRef<BasicBlock *> IndirectDests,
                  ArrayRef<Value *> Args,
                  ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                  const Twine &NameStr, Instruction *InsertBefore);

inline CallBrInst(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
                  ArrayRef<BasicBlock *> IndirectDests,
                  ArrayRef<Value *> Args,
                  ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                  const Twine &NameStr, BasicBlock *InsertAtEnd);

void init(FunctionType *FTy, Value *Func, BasicBlock *DefaultDest,
          ArrayRef<BasicBlock *> IndirectDests, ArrayRef<Value *> Args,
          ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);

/// Should the Indirect Destinations change, scan + update the Arg list.
void updateArgBlockAddresses(unsigned i, BasicBlock *B);

/// Compute the number of operands to allocate.
static int ComputeNumOperands(int NumArgs, int NumIndirectDests,
                              int NumBundleInputs = 0) {
  // We need one operand for the called function, plus our extra operands and
  // the input operand counts provided.
  return 2 + NumIndirectDests + NumArgs + NumBundleInputs;
}

3951protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

CallBrInst *cloneImpl() const;

3957public:
static CallBrInst *Create(FunctionType *Ty, Value *Func,
                          BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args, const Twine &NameStr,
                          Instruction *InsertBefore = nullptr) {
  int NumOperands = ComputeNumOperands(Args.size(), IndirectDests.size());
  return new (NumOperands)
      CallBrInst(Ty, Func, DefaultDest, IndirectDests, Args, None,
                 NumOperands, NameStr, InsertBefore);
}

static CallBrInst *Create(FunctionType *Ty, Value *Func,
                          BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles = None,
                          const Twine &NameStr = "",
                          Instruction *InsertBefore = nullptr) {
  int NumOperands = ComputeNumOperands(Args.size(), IndirectDests.size(),
                                       CountBundleInputs(Bundles));
  unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);

  return new (NumOperands, DescriptorBytes)
      CallBrInst(Ty, Func, DefaultDest, IndirectDests, Args, Bundles,
                 NumOperands, NameStr, InsertBefore);
}

static CallBrInst *Create(FunctionType *Ty, Value *Func,
                          BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args, const Twine &NameStr,
                          BasicBlock *InsertAtEnd) {
  int NumOperands = ComputeNumOperands(Args.size(), IndirectDests.size());
  return new (NumOperands)
      CallBrInst(Ty, Func, DefaultDest, IndirectDests, Args, None,
                 NumOperands, NameStr, InsertAtEnd);
}

static CallBrInst *Create(FunctionType *Ty, Value *Func,
                          BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles,
                          const Twine &NameStr, BasicBlock *InsertAtEnd) {
  int NumOperands = ComputeNumOperands(Args.size(), IndirectDests.size(),
                                       CountBundleInputs(Bundles));
  unsigned DescriptorBytes = Bundles.size() * sizeof(BundleOpInfo);

  return new (NumOperands, DescriptorBytes)
      CallBrInst(Ty, Func, DefaultDest, IndirectDests, Args, Bundles,
                 NumOperands, NameStr, InsertAtEnd);
}

static CallBrInst *Create(FunctionCallee Func, BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args, const Twine &NameStr,
                          Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), DefaultDest,
                IndirectDests, Args, NameStr, InsertBefore);
}

static CallBrInst *Create(FunctionCallee Func, BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles = None,
                          const Twine &NameStr = "",
                          Instruction *InsertBefore = nullptr) {
  return Create(Func.getFunctionType(), Func.getCallee(), DefaultDest,
                IndirectDests, Args, Bundles, NameStr, InsertBefore);
}

static CallBrInst *Create(FunctionCallee Func, BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args, const Twine &NameStr,
                          BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), DefaultDest,
                IndirectDests, Args, NameStr, InsertAtEnd);
}

static CallBrInst *Create(FunctionCallee Func,
                          BasicBlock *DefaultDest,
                          ArrayRef<BasicBlock *> IndirectDests,
                          ArrayRef<Value *> Args,
                          ArrayRef<OperandBundleDef> Bundles,
                          const Twine &NameStr, BasicBlock *InsertAtEnd) {
  return Create(Func.getFunctionType(), Func.getCallee(), DefaultDest,
                IndirectDests, Args, Bundles, NameStr, InsertAtEnd);
}

/// Create a clone of \p CBI with a different set of operand bundles and
/// insert it before \p InsertPt.
///
/// The returned callbr instruction is identical to \p CBI in every way
/// except that the operand bundles for the new instruction are set to the
/// operand bundles in \p Bundles.
static CallBrInst *Create(CallBrInst *CBI,
                          ArrayRef<OperandBundleDef> Bundles,
                          Instruction *InsertPt = nullptr);

/// Return the number of callbr indirect dest labels.
///
unsigned getNumIndirectDests() const { return NumIndirectDests; }

/// getIndirectDestLabel - Return the i-th indirect dest label.
///
Value *getIndirectDestLabel(unsigned i) const {
  assert(i < getNumIndirectDests() && "Out of bounds!")((i < getNumIndirectDests() && "Out of bounds!") ?
 static_cast<void> (0) : __assert_fail ("i < getNumIndirectDests() && \"Out of bounds!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4064, __PRETTY_FUNCTION__));
  return getOperand(i + getNumArgOperands() + getNumTotalBundleOperands() +
                    1);
}

Value *getIndirectDestLabelUse(unsigned i) const {
  assert(i < getNumIndirectDests() && "Out of bounds!")((i < getNumIndirectDests() && "Out of bounds!") ?
 static_cast<void> (0) : __assert_fail ("i < getNumIndirectDests() && \"Out of bounds!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4070, __PRETTY_FUNCTION__));
  return getOperandUse(i + getNumArgOperands() + getNumTotalBundleOperands() +
                       1);
}

// Return the destination basic blocks...
BasicBlock *getDefaultDest() const {
  return cast<BasicBlock>(*(&Op<-1>() - getNumIndirectDests() - 1));
}
BasicBlock *getIndirectDest(unsigned i) const {
  return cast_or_null<BasicBlock>(*(&Op<-1>() - getNumIndirectDests() + i));
}
SmallVector<BasicBlock *, 16> getIndirectDests() const {
  SmallVector<BasicBlock *, 16> IndirectDests;
  for (unsigned i = 0, e = getNumIndirectDests(); i < e; ++i)
    IndirectDests.push_back(getIndirectDest(i));
  return IndirectDests;
}
void setDefaultDest(BasicBlock *B) {
  *(&Op<-1>() - getNumIndirectDests() - 1) = reinterpret_cast<Value *>(B);
}
void setIndirectDest(unsigned i, BasicBlock *B) {
  updateArgBlockAddresses(i, B);
  *(&Op<-1>() - getNumIndirectDests() + i) = reinterpret_cast<Value *>(B);
}

BasicBlock *getSuccessor(unsigned i) const {
  assert(i < getNumSuccessors() + 1 &&((i < getNumSuccessors() + 1 && "Successor # out of range for callbr!"
) ? static_cast<void> (0) : __assert_fail ("i < getNumSuccessors() + 1 && \"Successor # out of range for callbr!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4098, __PRETTY_FUNCTION__))
         "Successor # out of range for callbr!")((i < getNumSuccessors() + 1 && "Successor # out of range for callbr!"
) ? static_cast<void> (0) : __assert_fail ("i < getNumSuccessors() + 1 && \"Successor # out of range for callbr!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4098, __PRETTY_FUNCTION__));
  return i == 0 ? getDefaultDest() : getIndirectDest(i - 1);
}

void setSuccessor(unsigned i, BasicBlock *NewSucc) {
  assert(i < getNumIndirectDests() + 1 &&((i < getNumIndirectDests() + 1 && "Successor # out of range for callbr!"
) ? static_cast<void> (0) : __assert_fail ("i < getNumIndirectDests() + 1 && \"Successor # out of range for callbr!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4104, __PRETTY_FUNCTION__))
         "Successor # out of range for callbr!")((i < getNumIndirectDests() + 1 && "Successor # out of range for callbr!"
) ? static_cast<void> (0) : __assert_fail ("i < getNumIndirectDests() + 1 && \"Successor # out of range for callbr!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4104, __PRETTY_FUNCTION__));
  return i == 0 ? setDefaultDest(NewSucc) : setIndirectDest(i - 1, NewSucc);
}

unsigned getNumSuccessors() const { return getNumIndirectDests() + 1; }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::CallBr);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

4118private:
// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}
4125};

4127CallBrInst::CallBrInst(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
                     ArrayRef<BasicBlock *> IndirectDests,
                     ArrayRef<Value *> Args,
                     ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                     const Twine &NameStr, Instruction *InsertBefore)
  : CallBase(Ty->getReturnType(), Instruction::CallBr,
             OperandTraits<CallBase>::op_end(this) - NumOperands, NumOperands,
             InsertBefore) {
init(Ty, Func, DefaultDest, IndirectDests, Args, Bundles, NameStr);
4136}

4138CallBrInst::CallBrInst(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
                     ArrayRef<BasicBlock *> IndirectDests,
                     ArrayRef<Value *> Args,
                     ArrayRef<OperandBundleDef> Bundles, int NumOperands,
                     const Twine &NameStr, BasicBlock *InsertAtEnd)
  : CallBase(Ty->getReturnType(), Instruction::CallBr,
             OperandTraits<CallBase>::op_end(this) - NumOperands, NumOperands,
             InsertAtEnd) {
init(Ty, Func, DefaultDest, IndirectDests, Args, Bundles, NameStr);
4147}

4149//===----------------------------------------------------------------------===//
4150//                              ResumeInst Class
4151//===----------------------------------------------------------------------===//

4153//===---------------------------------------------------------------------------
4154/// Resume the propagation of an exception.
4155///
4156class ResumeInst : public Instruction {
ResumeInst(const ResumeInst &RI);

explicit ResumeInst(Value *Exn, Instruction *InsertBefore=nullptr);
ResumeInst(Value *Exn, BasicBlock *InsertAtEnd);

4162protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

ResumeInst *cloneImpl() const;

4168public:
static ResumeInst *Create(Value *Exn, Instruction *InsertBefore = nullptr) {
  return new(1) ResumeInst(Exn, InsertBefore);
}

static ResumeInst *Create(Value *Exn, BasicBlock *InsertAtEnd) {
  return new(1) ResumeInst(Exn, InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Convenience accessor.
Value *getValue() const { return Op<0>(); }

unsigned getNumSuccessors() const { return 0; }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Resume;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

4193private:
BasicBlock *getSuccessor(unsigned idx) const {
  llvm_unreachable("ResumeInst has no successors!")::llvm::llvm_unreachable_internal("ResumeInst has no successors!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4195);
}

void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
  llvm_unreachable("ResumeInst has no successors!")::llvm::llvm_unreachable_internal("ResumeInst has no successors!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4199);
}
4201};

4203template <>
4204struct OperandTraits<ResumeInst> :
  public FixedNumOperandTraits<ResumeInst, 1> {
4206};

4208DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ResumeInst, Value)ResumeInst::op_iterator ResumeInst::op_begin() { return OperandTraits
<ResumeInst>::op_begin(this); } ResumeInst::const_op_iterator
 ResumeInst::op_begin() const { return OperandTraits<ResumeInst
>::op_begin(const_cast<ResumeInst*>(this)); } ResumeInst
::op_iterator ResumeInst::op_end() { return OperandTraits<
ResumeInst>::op_end(this); } ResumeInst::const_op_iterator
 ResumeInst::op_end() const { return OperandTraits<ResumeInst
>::op_end(const_cast<ResumeInst*>(this)); } Value *ResumeInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<ResumeInst>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ResumeInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4208, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<ResumeInst>::op_begin(const_cast<ResumeInst
*>(this))[i_nocapture].get()); } void ResumeInst::setOperand
(unsigned i_nocapture, Value *Val_nocapture) { ((i_nocapture <
 OperandTraits<ResumeInst>::operands(this) && "setOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<ResumeInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4208, __PRETTY_FUNCTION__)); OperandTraits<ResumeInst>
::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned ResumeInst
::getNumOperands() const { return OperandTraits<ResumeInst
>::operands(this); } template <int Idx_nocapture> Use
 &ResumeInst::Op() { return this->OpFrom<Idx_nocapture
>(this); } template <int Idx_nocapture> const Use &
ResumeInst::Op() const { return this->OpFrom<Idx_nocapture
>(this); }

4210//===----------------------------------------------------------------------===//
4211//                         CatchSwitchInst Class
4212//===----------------------------------------------------------------------===//
4213class CatchSwitchInst : public Instruction {
using UnwindDestField = BoolBitfieldElementT<0>;

/// The number of operands actually allocated.  NumOperands is
/// the number actually in use.
unsigned ReservedSpace;

// Operand[0] = Outer scope
// Operand[1] = Unwind block destination
// Operand[n] = BasicBlock to go to on match
CatchSwitchInst(const CatchSwitchInst &CSI);

/// Create a new switch instruction, specifying a
/// default destination.  The number of additional handlers can be specified
/// here to make memory allocation more efficient.
/// This constructor can also autoinsert before another instruction.
CatchSwitchInst(Value *ParentPad, BasicBlock *UnwindDest,
                unsigned NumHandlers, const Twine &NameStr,
                Instruction *InsertBefore);

/// Create a new switch instruction, specifying a
/// default destination.  The number of additional handlers can be specified
/// here to make memory allocation more efficient.
/// This constructor also autoinserts at the end of the specified BasicBlock.
CatchSwitchInst(Value *ParentPad, BasicBlock *UnwindDest,
                unsigned NumHandlers, const Twine &NameStr,
                BasicBlock *InsertAtEnd);

// allocate space for exactly zero operands
void *operator new(size_t s) { return User::operator new(s); }

void init(Value *ParentPad, BasicBlock *UnwindDest, unsigned NumReserved);
void growOperands(unsigned Size);

4247protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

CatchSwitchInst *cloneImpl() const;

4253public:
static CatchSwitchInst *Create(Value *ParentPad, BasicBlock *UnwindDest,
                               unsigned NumHandlers,
                               const Twine &NameStr = "",
                               Instruction *InsertBefore = nullptr) {
  return new CatchSwitchInst(ParentPad, UnwindDest, NumHandlers, NameStr,
                             InsertBefore);
}

static CatchSwitchInst *Create(Value *ParentPad, BasicBlock *UnwindDest,
                               unsigned NumHandlers, const Twine &NameStr,
                               BasicBlock *InsertAtEnd) {
  return new CatchSwitchInst(ParentPad, UnwindDest, NumHandlers, NameStr,
                             InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

// Accessor Methods for CatchSwitch stmt
Value *getParentPad() const { return getOperand(0); }
void setParentPad(Value *ParentPad) { setOperand(0, ParentPad); }

// Accessor Methods for CatchSwitch stmt
bool hasUnwindDest() const { return getSubclassData<UnwindDestField>(); }
bool unwindsToCaller() const { return !hasUnwindDest(); }
BasicBlock *getUnwindDest() const {
  if (hasUnwindDest())
    return cast<BasicBlock>(getOperand(1));
  return nullptr;
}
void setUnwindDest(BasicBlock *UnwindDest) {
  assert(UnwindDest)((UnwindDest) ? static_cast<void> (0) : __assert_fail (
"UnwindDest", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4285, __PRETTY_FUNCTION__));
  assert(hasUnwindDest())((hasUnwindDest()) ? static_cast<void> (0) : __assert_fail
 ("hasUnwindDest()", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4286, __PRETTY_FUNCTION__));
  setOperand(1, UnwindDest);
}

/// return the number of 'handlers' in this catchswitch
/// instruction, except the default handler
unsigned getNumHandlers() const {
  if (hasUnwindDest())
    return getNumOperands() - 2;
  return getNumOperands() - 1;
}

4298private:
static BasicBlock *handler_helper(Value *V) { return cast<BasicBlock>(V); }
static const BasicBlock *handler_helper(const Value *V) {
  return cast<BasicBlock>(V);
}

4304public:
using DerefFnTy = BasicBlock *(*)(Value *);
using handler_iterator = mapped_iterator<op_iterator, DerefFnTy>;
using handler_range = iterator_range<handler_iterator>;
using ConstDerefFnTy = const BasicBlock *(*)(const Value *);
using const_handler_iterator =
    mapped_iterator<const_op_iterator, ConstDerefFnTy>;
using const_handler_range = iterator_range<const_handler_iterator>;

/// Returns an iterator that points to the first handler in CatchSwitchInst.
handler_iterator handler_begin() {
  op_iterator It = op_begin() + 1;
  if (hasUnwindDest())
    ++It;
  return handler_iterator(It, DerefFnTy(handler_helper));
}

/// Returns an iterator that points to the first handler in the
/// CatchSwitchInst.
const_handler_iterator handler_begin() const {
  const_op_iterator It = op_begin() + 1;
  if (hasUnwindDest())
    ++It;
  return const_handler_iterator(It, ConstDerefFnTy(handler_helper));
}

/// Returns a read-only iterator that points one past the last
/// handler in the CatchSwitchInst.
handler_iterator handler_end() {
  return handler_iterator(op_end(), DerefFnTy(handler_helper));
}

/// Returns an iterator that points one past the last handler in the
/// CatchSwitchInst.
const_handler_iterator handler_end() const {
  return const_handler_iterator(op_end(), ConstDerefFnTy(handler_helper));
}

/// iteration adapter for range-for loops.
handler_range handlers() {
  return make_range(handler_begin(), handler_end());
}

/// iteration adapter for range-for loops.
const_handler_range handlers() const {
  return make_range(handler_begin(), handler_end());
}

/// Add an entry to the switch instruction...
/// Note:
/// This action invalidates handler_end(). Old handler_end() iterator will
/// point to the added handler.
void addHandler(BasicBlock *Dest);

void removeHandler(handler_iterator HI);

unsigned getNumSuccessors() const { return getNumOperands() - 1; }
BasicBlock *getSuccessor(unsigned Idx) const {
  assert(Idx < getNumSuccessors() &&((Idx < getNumSuccessors() && "Successor # out of range for catchswitch!"
) ? static_cast<void> (0) : __assert_fail ("Idx < getNumSuccessors() && \"Successor # out of range for catchswitch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4363, __PRETTY_FUNCTION__))
         "Successor # out of range for catchswitch!")((Idx < getNumSuccessors() && "Successor # out of range for catchswitch!"
) ? static_cast<void> (0) : __assert_fail ("Idx < getNumSuccessors() && \"Successor # out of range for catchswitch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4363, __PRETTY_FUNCTION__));
  return cast<BasicBlock>(getOperand(Idx + 1));
}
void setSuccessor(unsigned Idx, BasicBlock *NewSucc) {
  assert(Idx < getNumSuccessors() &&((Idx < getNumSuccessors() && "Successor # out of range for catchswitch!"
) ? static_cast<void> (0) : __assert_fail ("Idx < getNumSuccessors() && \"Successor # out of range for catchswitch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4368, __PRETTY_FUNCTION__))
         "Successor # out of range for catchswitch!")((Idx < getNumSuccessors() && "Successor # out of range for catchswitch!"
) ? static_cast<void> (0) : __assert_fail ("Idx < getNumSuccessors() && \"Successor # out of range for catchswitch!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4368, __PRETTY_FUNCTION__));
  setOperand(Idx + 1, NewSucc);
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::CatchSwitch;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4379};

4381template <>
4382struct OperandTraits<CatchSwitchInst> : public HungoffOperandTraits<2> {};

4384DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CatchSwitchInst, Value)CatchSwitchInst::op_iterator CatchSwitchInst::op_begin() { return
 OperandTraits<CatchSwitchInst>::op_begin(this); } CatchSwitchInst
::const_op_iterator CatchSwitchInst::op_begin() const { return
 OperandTraits<CatchSwitchInst>::op_begin(const_cast<
CatchSwitchInst*>(this)); } CatchSwitchInst::op_iterator CatchSwitchInst
::op_end() { return OperandTraits<CatchSwitchInst>::op_end
(this); } CatchSwitchInst::const_op_iterator CatchSwitchInst::
op_end() const { return OperandTraits<CatchSwitchInst>::
op_end(const_cast<CatchSwitchInst*>(this)); } Value *CatchSwitchInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<CatchSwitchInst>::operands(this) &&
 "getOperand() out of range!") ? static_cast<void> (0) :
 __assert_fail ("i_nocapture < OperandTraits<CatchSwitchInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4384, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<CatchSwitchInst>::op_begin(const_cast<
CatchSwitchInst*>(this))[i_nocapture].get()); } void CatchSwitchInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
i_nocapture < OperandTraits<CatchSwitchInst>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<CatchSwitchInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4384, __PRETTY_FUNCTION__)); OperandTraits<CatchSwitchInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 CatchSwitchInst::getNumOperands() const { return OperandTraits
<CatchSwitchInst>::operands(this); } template <int Idx_nocapture
> Use &CatchSwitchInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
 const Use &CatchSwitchInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }

4386//===----------------------------------------------------------------------===//
4387//                               CleanupPadInst Class
4388//===----------------------------------------------------------------------===//
4389class CleanupPadInst : public FuncletPadInst {
4390private:
explicit CleanupPadInst(Value *ParentPad, ArrayRef<Value *> Args,
                        unsigned Values, const Twine &NameStr,
                        Instruction *InsertBefore)
    : FuncletPadInst(Instruction::CleanupPad, ParentPad, Args, Values,
                     NameStr, InsertBefore) {}
explicit CleanupPadInst(Value *ParentPad, ArrayRef<Value *> Args,
                        unsigned Values, const Twine &NameStr,
                        BasicBlock *InsertAtEnd)
    : FuncletPadInst(Instruction::CleanupPad, ParentPad, Args, Values,
                     NameStr, InsertAtEnd) {}

4402public:
static CleanupPadInst *Create(Value *ParentPad, ArrayRef<Value *> Args = None,
                              const Twine &NameStr = "",
                              Instruction *InsertBefore = nullptr) {
  unsigned Values = 1 + Args.size();
  return new (Values)
      CleanupPadInst(ParentPad, Args, Values, NameStr, InsertBefore);
}

static CleanupPadInst *Create(Value *ParentPad, ArrayRef<Value *> Args,
                              const Twine &NameStr, BasicBlock *InsertAtEnd) {
  unsigned Values = 1 + Args.size();
  return new (Values)
      CleanupPadInst(ParentPad, Args, Values, NameStr, InsertAtEnd);
}

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::CleanupPad;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4425};

4427//===----------------------------------------------------------------------===//
4428//                               CatchPadInst Class
4429//===----------------------------------------------------------------------===//
4430class CatchPadInst : public FuncletPadInst {
4431private:
explicit CatchPadInst(Value *CatchSwitch, ArrayRef<Value *> Args,
                      unsigned Values, const Twine &NameStr,
                      Instruction *InsertBefore)
    : FuncletPadInst(Instruction::CatchPad, CatchSwitch, Args, Values,
                     NameStr, InsertBefore) {}
explicit CatchPadInst(Value *CatchSwitch, ArrayRef<Value *> Args,
                      unsigned Values, const Twine &NameStr,
                      BasicBlock *InsertAtEnd)
    : FuncletPadInst(Instruction::CatchPad, CatchSwitch, Args, Values,
                     NameStr, InsertAtEnd) {}

4443public:
static CatchPadInst *Create(Value *CatchSwitch, ArrayRef<Value *> Args,
                            const Twine &NameStr = "",
                            Instruction *InsertBefore = nullptr) {
  unsigned Values = 1 + Args.size();
  return new (Values)
      CatchPadInst(CatchSwitch, Args, Values, NameStr, InsertBefore);
}

static CatchPadInst *Create(Value *CatchSwitch, ArrayRef<Value *> Args,
                            const Twine &NameStr, BasicBlock *InsertAtEnd) {
  unsigned Values = 1 + Args.size();
  return new (Values)
      CatchPadInst(CatchSwitch, Args, Values, NameStr, InsertAtEnd);
}

/// Convenience accessors
CatchSwitchInst *getCatchSwitch() const {
  return cast<CatchSwitchInst>(Op<-1>());
}
void setCatchSwitch(Value *CatchSwitch) {
  assert(CatchSwitch)((CatchSwitch) ? static_cast<void> (0) : __assert_fail (
"CatchSwitch", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4464, __PRETTY_FUNCTION__));
  Op<-1>() = CatchSwitch;
}

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::CatchPad;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4475};

4477//===----------------------------------------------------------------------===//
4478//                               CatchReturnInst Class
4479//===----------------------------------------------------------------------===//

4481class CatchReturnInst : public Instruction {
CatchReturnInst(const CatchReturnInst &RI);
CatchReturnInst(Value *CatchPad, BasicBlock *BB, Instruction *InsertBefore);
CatchReturnInst(Value *CatchPad, BasicBlock *BB, BasicBlock *InsertAtEnd);

void init(Value *CatchPad, BasicBlock *BB);

4488protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

CatchReturnInst *cloneImpl() const;

4494public:
static CatchReturnInst *Create(Value *CatchPad, BasicBlock *BB,
                               Instruction *InsertBefore = nullptr) {
  assert(CatchPad)((CatchPad) ? static_cast<void> (0) : __assert_fail ("CatchPad"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4497, __PRETTY_FUNCTION__));
  assert(BB)((BB) ? static_cast<void> (0) : __assert_fail ("BB", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4498, __PRETTY_FUNCTION__));
  return new (2) CatchReturnInst(CatchPad, BB, InsertBefore);
}

static CatchReturnInst *Create(Value *CatchPad, BasicBlock *BB,
                               BasicBlock *InsertAtEnd) {
  assert(CatchPad)((CatchPad) ? static_cast<void> (0) : __assert_fail ("CatchPad"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4504, __PRETTY_FUNCTION__));
  assert(BB)((BB) ? static_cast<void> (0) : __assert_fail ("BB", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4505, __PRETTY_FUNCTION__));
  return new (2) CatchReturnInst(CatchPad, BB, InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Convenience accessors.
CatchPadInst *getCatchPad() const { return cast<CatchPadInst>(Op<0>()); }
void setCatchPad(CatchPadInst *CatchPad) {
  assert(CatchPad)((CatchPad) ? static_cast<void> (0) : __assert_fail ("CatchPad"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4515, __PRETTY_FUNCTION__));
  Op<0>() = CatchPad;
}

BasicBlock *getSuccessor() const { return cast<BasicBlock>(Op<1>()); }
void setSuccessor(BasicBlock *NewSucc) {
  assert(NewSucc)((NewSucc) ? static_cast<void> (0) : __assert_fail ("NewSucc"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4521, __PRETTY_FUNCTION__));
  Op<1>() = NewSucc;
}
unsigned getNumSuccessors() const { return 1; }

/// Get the parentPad of this catchret's catchpad's catchswitch.
/// The successor block is implicitly a member of this funclet.
Value *getCatchSwitchParentPad() const {
  return getCatchPad()->getCatchSwitch()->getParentPad();
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::CatchRet);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

4540private:
BasicBlock *getSuccessor(unsigned Idx) const {
  assert(Idx < getNumSuccessors() && "Successor # out of range for catchret!")((Idx < getNumSuccessors() && "Successor # out of range for catchret!"
) ? static_cast<void> (0) : __assert_fail ("Idx < getNumSuccessors() && \"Successor # out of range for catchret!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4542, __PRETTY_FUNCTION__));
  return getSuccessor();
}

void setSuccessor(unsigned Idx, BasicBlock *B) {
  assert(Idx < getNumSuccessors() && "Successor # out of range for catchret!")((Idx < getNumSuccessors() && "Successor # out of range for catchret!"
) ? static_cast<void> (0) : __assert_fail ("Idx < getNumSuccessors() && \"Successor # out of range for catchret!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4547, __PRETTY_FUNCTION__));
  setSuccessor(B);
}
4550};

4552template <>
4553struct OperandTraits<CatchReturnInst>
  : public FixedNumOperandTraits<CatchReturnInst, 2> {};

4556DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CatchReturnInst, Value)CatchReturnInst::op_iterator CatchReturnInst::op_begin() { return
 OperandTraits<CatchReturnInst>::op_begin(this); } CatchReturnInst
::const_op_iterator CatchReturnInst::op_begin() const { return
 OperandTraits<CatchReturnInst>::op_begin(const_cast<
CatchReturnInst*>(this)); } CatchReturnInst::op_iterator CatchReturnInst
::op_end() { return OperandTraits<CatchReturnInst>::op_end
(this); } CatchReturnInst::const_op_iterator CatchReturnInst::
op_end() const { return OperandTraits<CatchReturnInst>::
op_end(const_cast<CatchReturnInst*>(this)); } Value *CatchReturnInst
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
 OperandTraits<CatchReturnInst>::operands(this) &&
 "getOperand() out of range!") ? static_cast<void> (0) :
 __assert_fail ("i_nocapture < OperandTraits<CatchReturnInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4556, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<CatchReturnInst>::op_begin(const_cast<
CatchReturnInst*>(this))[i_nocapture].get()); } void CatchReturnInst
::setOperand(unsigned i_nocapture, Value *Val_nocapture) { ((
i_nocapture < OperandTraits<CatchReturnInst>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<CatchReturnInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4556, __PRETTY_FUNCTION__)); OperandTraits<CatchReturnInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 CatchReturnInst::getNumOperands() const { return OperandTraits
<CatchReturnInst>::operands(this); } template <int Idx_nocapture
> Use &CatchReturnInst::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
 const Use &CatchReturnInst::Op() const { return this->
OpFrom<Idx_nocapture>(this); }

4558//===----------------------------------------------------------------------===//
4559//                               CleanupReturnInst Class
4560//===----------------------------------------------------------------------===//

4562class CleanupReturnInst : public Instruction {
using UnwindDestField = BoolBitfieldElementT<0>;

4565private:
CleanupReturnInst(const CleanupReturnInst &RI);
CleanupReturnInst(Value *CleanupPad, BasicBlock *UnwindBB, unsigned Values,
                  Instruction *InsertBefore = nullptr);
CleanupReturnInst(Value *CleanupPad, BasicBlock *UnwindBB, unsigned Values,
                  BasicBlock *InsertAtEnd);

void init(Value *CleanupPad, BasicBlock *UnwindBB);

4574protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

CleanupReturnInst *cloneImpl() const;

4580public:
static CleanupReturnInst *Create(Value *CleanupPad,
                                 BasicBlock *UnwindBB = nullptr,
                                 Instruction *InsertBefore = nullptr) {
  assert(CleanupPad)((CleanupPad) ? static_cast<void> (0) : __assert_fail (
"CleanupPad", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4584, __PRETTY_FUNCTION__));
  unsigned Values = 1;
  if (UnwindBB)
    ++Values;
  return new (Values)
      CleanupReturnInst(CleanupPad, UnwindBB, Values, InsertBefore);
}

static CleanupReturnInst *Create(Value *CleanupPad, BasicBlock *UnwindBB,
                                 BasicBlock *InsertAtEnd) {
  assert(CleanupPad)((CleanupPad) ? static_cast<void> (0) : __assert_fail (
"CleanupPad", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4594, __PRETTY_FUNCTION__));
  unsigned Values = 1;
  if (UnwindBB)
    ++Values;
  return new (Values)
      CleanupReturnInst(CleanupPad, UnwindBB, Values, InsertAtEnd);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

bool hasUnwindDest() const { return getSubclassData<UnwindDestField>(); }
bool unwindsToCaller() const { return !hasUnwindDest(); }

/// Convenience accessor.
CleanupPadInst *getCleanupPad() const {
  return cast<CleanupPadInst>(Op<0>());
}
void setCleanupPad(CleanupPadInst *CleanupPad) {
  assert(CleanupPad)((CleanupPad) ? static_cast<void> (0) : __assert_fail (
"CleanupPad", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4613, __PRETTY_FUNCTION__));
  Op<0>() = CleanupPad;
}

unsigned getNumSuccessors() const { return hasUnwindDest() ? 1 : 0; }

BasicBlock *getUnwindDest() const {
  return hasUnwindDest() ? cast<BasicBlock>(Op<1>()) : nullptr;
}
void setUnwindDest(BasicBlock *NewDest) {
  assert(NewDest)((NewDest) ? static_cast<void> (0) : __assert_fail ("NewDest"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4623, __PRETTY_FUNCTION__));
  assert(hasUnwindDest())((hasUnwindDest()) ? static_cast<void> (0) : __assert_fail
 ("hasUnwindDest()", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4624, __PRETTY_FUNCTION__));
  Op<1>() = NewDest;
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return (I->getOpcode() == Instruction::CleanupRet);
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

4636private:
BasicBlock *getSuccessor(unsigned Idx) const {
  assert(Idx == 0)((Idx == 0) ? static_cast<void> (0) : __assert_fail ("Idx == 0"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4638, __PRETTY_FUNCTION__));
  return getUnwindDest();
}

void setSuccessor(unsigned Idx, BasicBlock *B) {
  assert(Idx == 0)((Idx == 0) ? static_cast<void> (0) : __assert_fail ("Idx == 0"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4643, __PRETTY_FUNCTION__));
  setUnwindDest(B);
}

// Shadow Instruction::setInstructionSubclassData with a private forwarding
// method so that subclasses cannot accidentally use it.
template <typename Bitfield>
void setSubclassData(typename Bitfield::Type Value) {
  Instruction::setSubclassData<Bitfield>(Value);
}
4653};

4655template <>
4656struct OperandTraits<CleanupReturnInst>
  : public VariadicOperandTraits<CleanupReturnInst, /*MINARITY=*/1> {};

4659DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CleanupReturnInst, Value)CleanupReturnInst::op_iterator CleanupReturnInst::op_begin() {
 return OperandTraits<CleanupReturnInst>::op_begin(this
); } CleanupReturnInst::const_op_iterator CleanupReturnInst::
op_begin() const { return OperandTraits<CleanupReturnInst>
::op_begin(const_cast<CleanupReturnInst*>(this)); } CleanupReturnInst
::op_iterator CleanupReturnInst::op_end() { return OperandTraits
<CleanupReturnInst>::op_end(this); } CleanupReturnInst::
const_op_iterator CleanupReturnInst::op_end() const { return OperandTraits
<CleanupReturnInst>::op_end(const_cast<CleanupReturnInst
*>(this)); } Value *CleanupReturnInst::getOperand(unsigned
 i_nocapture) const { ((i_nocapture < OperandTraits<CleanupReturnInst
>::operands(this) && "getOperand() out of range!")
 ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<CleanupReturnInst>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4659, __PRETTY_FUNCTION__)); return cast_or_null<Value>
( OperandTraits<CleanupReturnInst>::op_begin(const_cast
<CleanupReturnInst*>(this))[i_nocapture].get()); } void
 CleanupReturnInst::setOperand(unsigned i_nocapture, Value *Val_nocapture
) { ((i_nocapture < OperandTraits<CleanupReturnInst>
::operands(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<CleanupReturnInst>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4659, __PRETTY_FUNCTION__)); OperandTraits<CleanupReturnInst
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 CleanupReturnInst::getNumOperands() const { return OperandTraits
<CleanupReturnInst>::operands(this); } template <int
 Idx_nocapture> Use &CleanupReturnInst::Op() { return this
->OpFrom<Idx_nocapture>(this); } template <int Idx_nocapture
> const Use &CleanupReturnInst::Op() const { return this
->OpFrom<Idx_nocapture>(this); }

4661//===----------------------------------------------------------------------===//
4662//                           UnreachableInst Class
4663//===----------------------------------------------------------------------===//

4665//===---------------------------------------------------------------------------
4666/// This function has undefined behavior.  In particular, the
4667/// presence of this instruction indicates some higher level knowledge that the
4668/// end of the block cannot be reached.
4669///
4670class UnreachableInst : public Instruction {
4671protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

UnreachableInst *cloneImpl() const;

4677public:
explicit UnreachableInst(LLVMContext &C, Instruction *InsertBefore = nullptr);
explicit UnreachableInst(LLVMContext &C, BasicBlock *InsertAtEnd);

// allocate space for exactly zero operands
void *operator new(size_t s) {
  return User::operator new(s, 0);
}

unsigned getNumSuccessors() const { return 0; }

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Instruction::Unreachable;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

4696private:
BasicBlock *getSuccessor(unsigned idx) const {
  llvm_unreachable("UnreachableInst has no successors!")::llvm::llvm_unreachable_internal("UnreachableInst has no successors!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4698);
}

void setSuccessor(unsigned idx, BasicBlock *B) {
  llvm_unreachable("UnreachableInst has no successors!")::llvm::llvm_unreachable_internal("UnreachableInst has no successors!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 4702);
}
4704};

4706//===----------------------------------------------------------------------===//
4707//                                 TruncInst Class
4708//===----------------------------------------------------------------------===//

4710/// This class represents a truncation of integer types.
4711class TruncInst : public CastInst {
4712protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical TruncInst
TruncInst *cloneImpl() const;

4719public:
/// Constructor with insert-before-instruction semantics
TruncInst(
  Value *S,                           ///< The value to be truncated
  Type *Ty,                           ///< The (smaller) type to truncate to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
TruncInst(
  Value *S,                     ///< The value to be truncated
  Type *Ty,                     ///< The (smaller) type to truncate to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == Trunc;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4743};

4745//===----------------------------------------------------------------------===//
4746//                                 ZExtInst Class
4747//===----------------------------------------------------------------------===//

4749/// This class represents zero extension of integer types.
4750class ZExtInst : public CastInst {
4751protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical ZExtInst
ZExtInst *cloneImpl() const;

4758public:
/// Constructor with insert-before-instruction semantics
ZExtInst(
  Value *S,                           ///< The value to be zero extended
  Type *Ty,                           ///< The type to zero extend to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end semantics.
ZExtInst(
  Value *S,                     ///< The value to be zero extended
  Type *Ty,                     ///< The type to zero extend to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == ZExt;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4782};

4784//===----------------------------------------------------------------------===//
4785//                                 SExtInst Class
4786//===----------------------------------------------------------------------===//

4788/// This class represents a sign extension of integer types.
4789class SExtInst : public CastInst {
4790protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical SExtInst
SExtInst *cloneImpl() const;

4797public:
/// Constructor with insert-before-instruction semantics
SExtInst(
  Value *S,                           ///< The value to be sign extended
  Type *Ty,                           ///< The type to sign extend to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
SExtInst(
  Value *S,                     ///< The value to be sign extended
  Type *Ty,                     ///< The type to sign extend to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == SExt;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4821};

4823//===----------------------------------------------------------------------===//
4824//                                 FPTruncInst Class
4825//===----------------------------------------------------------------------===//

4827/// This class represents a truncation of floating point types.
4828class FPTruncInst : public CastInst {
4829protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical FPTruncInst
FPTruncInst *cloneImpl() const;

4836public:
/// Constructor with insert-before-instruction semantics
FPTruncInst(
  Value *S,                           ///< The value to be truncated
  Type *Ty,                           ///< The type to truncate to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-before-instruction semantics
FPTruncInst(
  Value *S,                     ///< The value to be truncated
  Type *Ty,                     ///< The type to truncate to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == FPTrunc;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4860};

4862//===----------------------------------------------------------------------===//
4863//                                 FPExtInst Class
4864//===----------------------------------------------------------------------===//

4866/// This class represents an extension of floating point types.
4867class FPExtInst : public CastInst {
4868protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical FPExtInst
FPExtInst *cloneImpl() const;

4875public:
/// Constructor with insert-before-instruction semantics
FPExtInst(
  Value *S,                           ///< The value to be extended
  Type *Ty,                           ///< The type to extend to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
FPExtInst(
  Value *S,                     ///< The value to be extended
  Type *Ty,                     ///< The type to extend to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == FPExt;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4899};

4901//===----------------------------------------------------------------------===//
4902//                                 UIToFPInst Class
4903//===----------------------------------------------------------------------===//

4905/// This class represents a cast unsigned integer to floating point.
4906class UIToFPInst : public CastInst {
4907protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical UIToFPInst
UIToFPInst *cloneImpl() const;

4914public:
/// Constructor with insert-before-instruction semantics
UIToFPInst(
  Value *S,                           ///< The value to be converted
  Type *Ty,                           ///< The type to convert to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
UIToFPInst(
  Value *S,                     ///< The value to be converted
  Type *Ty,                     ///< The type to convert to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == UIToFP;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4938};

4940//===----------------------------------------------------------------------===//
4941//                                 SIToFPInst Class
4942//===----------------------------------------------------------------------===//

4944/// This class represents a cast from signed integer to floating point.
4945class SIToFPInst : public CastInst {
4946protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical SIToFPInst
SIToFPInst *cloneImpl() const;

4953public:
/// Constructor with insert-before-instruction semantics
SIToFPInst(
  Value *S,                           ///< The value to be converted
  Type *Ty,                           ///< The type to convert to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
SIToFPInst(
  Value *S,                     ///< The value to be converted
  Type *Ty,                     ///< The type to convert to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == SIToFP;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
4977};

4979//===----------------------------------------------------------------------===//
4980//                                 FPToUIInst Class
4981//===----------------------------------------------------------------------===//

4983/// This class represents a cast from floating point to unsigned integer
4984class FPToUIInst  : public CastInst {
4985protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical FPToUIInst
FPToUIInst *cloneImpl() const;

4992public:
/// Constructor with insert-before-instruction semantics
FPToUIInst(
  Value *S,                           ///< The value to be converted
  Type *Ty,                           ///< The type to convert to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
FPToUIInst(
  Value *S,                     ///< The value to be converted
  Type *Ty,                     ///< The type to convert to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< Where to insert the new instruction
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == FPToUI;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
5016};

5018//===----------------------------------------------------------------------===//
5019//                                 FPToSIInst Class
5020//===----------------------------------------------------------------------===//

5022/// This class represents a cast from floating point to signed integer.
5023class FPToSIInst  : public CastInst {
5024protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical FPToSIInst
FPToSIInst *cloneImpl() const;

5031public:
/// Constructor with insert-before-instruction semantics
FPToSIInst(
  Value *S,                           ///< The value to be converted
  Type *Ty,                           ///< The type to convert to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
FPToSIInst(
  Value *S,                     ///< The value to be converted
  Type *Ty,                     ///< The type to convert to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == FPToSI;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
5055};

5057//===----------------------------------------------------------------------===//
5058//                                 IntToPtrInst Class
5059//===----------------------------------------------------------------------===//

5061/// This class represents a cast from an integer to a pointer.
5062class IntToPtrInst : public CastInst {
5063public:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Constructor with insert-before-instruction semantics
IntToPtrInst(
  Value *S,                           ///< The value to be converted
  Type *Ty,                           ///< The type to convert to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
IntToPtrInst(
  Value *S,                     ///< The value to be converted
  Type *Ty,                     ///< The type to convert to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Clone an identical IntToPtrInst.
IntToPtrInst *cloneImpl() const;

/// Returns the address space of this instruction's pointer type.
unsigned getAddressSpace() const {
  return getType()->getPointerAddressSpace();
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == IntToPtr;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
5098};

5100//===----------------------------------------------------------------------===//
5101//                                 PtrToIntInst Class
5102//===----------------------------------------------------------------------===//

5104/// This class represents a cast from a pointer to an integer.
5105class PtrToIntInst : public CastInst {
5106protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical PtrToIntInst.
PtrToIntInst *cloneImpl() const;

5113public:
/// Constructor with insert-before-instruction semantics
PtrToIntInst(
  Value *S,                           ///< The value to be converted
  Type *Ty,                           ///< The type to convert to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
PtrToIntInst(
  Value *S,                     ///< The value to be converted
  Type *Ty,                     ///< The type to convert to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

/// Gets the pointer operand.
Value *getPointerOperand() { return getOperand(0); }
/// Gets the pointer operand.
const Value *getPointerOperand() const { return getOperand(0); }
/// Gets the operand index of the pointer operand.
static unsigned getPointerOperandIndex() { return 0U; }

/// Returns the address space of the pointer operand.
unsigned getPointerAddressSpace() const {
  return getPointerOperand()->getType()->getPointerAddressSpace();
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == PtrToInt;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
5149};

5151//===----------------------------------------------------------------------===//
5152//                             BitCastInst Class
5153//===----------------------------------------------------------------------===//

5155/// This class represents a no-op cast from one type to another.
5156class BitCastInst : public CastInst {
5157protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical BitCastInst.
BitCastInst *cloneImpl() const;

5164public:
/// Constructor with insert-before-instruction semantics
BitCastInst(
  Value *S,                           ///< The value to be casted
  Type *Ty,                           ///< The type to casted to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
BitCastInst(
  Value *S,                     ///< The value to be casted
  Type *Ty,                     ///< The type to casted to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == BitCast;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
5188};

5190//===----------------------------------------------------------------------===//
5191//                          AddrSpaceCastInst Class
5192//===----------------------------------------------------------------------===//

5194/// This class represents a conversion between pointers from one address space
5195/// to another.
5196class AddrSpaceCastInst : public CastInst {
5197protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical AddrSpaceCastInst.
AddrSpaceCastInst *cloneImpl() const;

5204public:
/// Constructor with insert-before-instruction semantics
AddrSpaceCastInst(
  Value *S,                           ///< The value to be casted
  Type *Ty,                           ///< The type to casted to
  const Twine &NameStr = "",          ///< A name for the new instruction
  Instruction *InsertBefore = nullptr ///< Where to insert the new instruction
);

/// Constructor with insert-at-end-of-block semantics
AddrSpaceCastInst(
  Value *S,                     ///< The value to be casted
  Type *Ty,                     ///< The type to casted to
  const Twine &NameStr,         ///< A name for the new instruction
  BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
);

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Instruction *I) {
  return I->getOpcode() == AddrSpaceCast;
}
static bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}

/// Gets the pointer operand.
Value *getPointerOperand() {
  return getOperand(0);
}

/// Gets the pointer operand.
const Value *getPointerOperand() const {
  return getOperand(0);
}

/// Gets the operand index of the pointer operand.
static unsigned getPointerOperandIndex() {
  return 0U;
}

/// Returns the address space of the pointer operand.
unsigned getSrcAddressSpace() const {
  return getPointerOperand()->getType()->getPointerAddressSpace();
}

/// Returns the address space of the result.
unsigned getDestAddressSpace() const {
  return getType()->getPointerAddressSpace();
}
5253};

5255/// A helper function that returns the pointer operand of a load or store
5256/// instruction. Returns nullptr if not load or store.
5257inline const Value *getLoadStorePointerOperand(const Value *V) {
if (auto *Load = dyn_cast<LoadInst>(V))
  return Load->getPointerOperand();
if (auto *Store = dyn_cast<StoreInst>(V))
  return Store->getPointerOperand();
return nullptr;
5263}
5264inline Value *getLoadStorePointerOperand(Value *V) {
return const_cast<Value *>(
    getLoadStorePointerOperand(static_cast<const Value *>(V)));
5267}

5269/// A helper function that returns the pointer operand of a load, store
5270/// or GEP instruction. Returns nullptr if not load, store, or GEP.
5271inline const Value *getPointerOperand(const Value *V) {
if (auto *Ptr = getLoadStorePointerOperand(V))
  return Ptr;
if (auto *Gep = dyn_cast<GetElementPtrInst>(V))
  return Gep->getPointerOperand();
return nullptr;
5277}
5278inline Value *getPointerOperand(Value *V) {
return const_cast<Value *>(getPointerOperand(static_cast<const Value *>(V)));
5280}

5282/// A helper function that returns the alignment of load or store instruction.
5283inline Align getLoadStoreAlignment(Value *I) {
assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&(((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
 "Expected Load or Store instruction") ? static_cast<void>
 (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Expected Load or Store instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 5285, __PRETTY_FUNCTION__))
       "Expected Load or Store instruction")(((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
 "Expected Load or Store instruction") ? static_cast<void>
 (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Expected Load or Store instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 5285, __PRETTY_FUNCTION__));
if (auto *LI = dyn_cast<LoadInst>(I))
  return LI->getAlign();
return cast<StoreInst>(I)->getAlign();
5289}

5291/// A helper function that returns the address space of the pointer operand of
5292/// load or store instruction.
5293inline unsigned getLoadStoreAddressSpace(Value *I) {
assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&(((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
 "Expected Load or Store instruction") ? static_cast<void>
 (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Expected Load or Store instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 5295, __PRETTY_FUNCTION__))
       "Expected Load or Store instruction")(((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
 "Expected Load or Store instruction") ? static_cast<void>
 (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Expected Load or Store instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Instructions.h"
, 5295, __PRETTY_FUNCTION__));
if (auto *LI = dyn_cast<LoadInst>(I))
  return LI->getPointerAddressSpace();
return cast<StoreInst>(I)->getPointerAddressSpace();
5299}

5301//===----------------------------------------------------------------------===//
5302//                              FreezeInst Class
5303//===----------------------------------------------------------------------===//

5305/// This class represents a freeze function that returns random concrete
5306/// value if an operand is either a poison value or an undef value
5307class FreezeInst : public UnaryInstruction {
5308protected:
// Note: Instruction needs to be a friend here to call cloneImpl.
friend class Instruction;

/// Clone an identical FreezeInst
FreezeInst *cloneImpl() const;

5315public:
explicit FreezeInst(Value *S,
                    const Twine &NameStr = "",
                    Instruction *InsertBefore = nullptr);
FreezeInst(Value *S, const Twine &NameStr, BasicBlock *InsertAtEnd);

// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const Instruction *I) {
  return I->getOpcode() == Freeze;
}
static inline bool classof(const Value *V) {
  return isa<Instruction>(V) && classof(cast<Instruction>(V));
}
5328};

5330} // end namespace llvm

5332#endif // LLVM_IR_INSTRUCTIONS_H

←

/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h

→

1//===- llvm/Value.h - Definition of the Value class -------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file declares the Value class.
10//
11//===----------------------------------------------------------------------===//

13#ifndef LLVM_IR_VALUE_H
14#define LLVM_IR_VALUE_H

16#include "llvm-c/Types.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/StringRef.h"
19#include "llvm/ADT/iterator_range.h"
20#include "llvm/IR/Use.h"
21#include "llvm/Support/Alignment.h"
22#include "llvm/Support/CBindingWrapping.h"
23#include "llvm/Support/Casting.h"
24#include <cassert>
25#include <iterator>
26#include <memory>

28namespace llvm {

30class APInt;
31class Argument;
32class BasicBlock;
33class Constant;
34class ConstantData;
35class ConstantAggregate;
36class DataLayout;
37class Function;
38class GlobalAlias;
39class GlobalIFunc;
40class GlobalIndirectSymbol;
41class GlobalObject;
42class GlobalValue;
43class GlobalVariable;
44class InlineAsm;
45class Instruction;
46class LLVMContext;
47class MDNode;
48class Module;
49class ModuleSlotTracker;
50class raw_ostream;
51template<typename ValueTy> class StringMapEntry;
52class Twine;
53class Type;
54class User;

56using ValueName = StringMapEntry<Value *>;

58//===----------------------------------------------------------------------===//
59//                                 Value Class
60//===----------------------------------------------------------------------===//

62/// LLVM Value Representation
63///
64/// This is a very important LLVM class. It is the base class of all values
65/// computed by a program that may be used as operands to other values. Value is
66/// the super class of other important classes such as Instruction and Function.
67/// All Values have a Type. Type is not a subclass of Value. Some values can
68/// have a name and they belong to some Module.  Setting the name on the Value
69/// automatically updates the module's symbol table.
70///
71/// Every value has a "use list" that keeps track of which other Values are
72/// using this Value.  A Value can also have an arbitrary number of ValueHandle
73/// objects that watch it and listen to RAUW and Destroy events.  See
74/// llvm/IR/ValueHandle.h for details.
75class Value {
Type *VTy;
Use *UseList;

friend class ValueAsMetadata; // Allow access to IsUsedByMD.
friend class ValueHandleBase;

const unsigned char SubclassID;   // Subclass identifier (for isa/dyn_cast)
unsigned char HasValueHandle : 1; // Has a ValueHandle pointing to this?

85protected:
/// Hold subclass data that can be dropped.
///
/// This member is similar to SubclassData, however it is for holding
/// information which may be used to aid optimization, but which may be
/// cleared to zero without affecting conservative interpretation.
unsigned char SubclassOptionalData : 7;

93private:
/// Hold arbitrary subclass data.
///
/// This member is defined by this class, but is not used for anything.
/// Subclasses can use it to hold whatever state they find useful.  This
/// field is initialized to zero by the ctor.
unsigned short SubclassData;

101protected:
/// The number of operands in the subclass.
///
/// This member is defined by this class, but not used for anything.
/// Subclasses can use it to store their number of operands, if they have
/// any.
///
/// This is stored here to save space in User on 64-bit hosts.  Since most
/// instances of Value have operands, 32-bit hosts aren't significantly
/// affected.
///
/// Note, this should *NOT* be used directly by any class other than User.
/// User uses this value to find the Use list.
enum : unsigned { NumUserOperandsBits = 27 };
unsigned NumUserOperands : NumUserOperandsBits;

// Use the same type as the bitfield above so that MSVC will pack them.
unsigned IsUsedByMD : 1;
unsigned HasName : 1;
unsigned HasMetadata : 1; // Has metadata attached to this?
unsigned HasHungOffUses : 1;
unsigned HasDescriptor : 1;

124private:
template <typename UseT> // UseT == 'Use' or 'const Use'
class use_iterator_impl
    : public std::iterator<std::forward_iterator_tag, UseT *> {
  friend class Value;

  UseT *U;

  explicit use_iterator_impl(UseT *u) : U(u) {}

public:
  use_iterator_impl() : U() {}

  bool operator==(const use_iterator_impl &x) const { return U == x.U; }
  bool operator!=(const use_iterator_impl &x) const { return !operator==(x); }

  use_iterator_impl &operator++() { // Preincrement
    assert(U && "Cannot increment end iterator!")((U && "Cannot increment end iterator!") ? static_cast
<void> (0) : __assert_fail ("U && \"Cannot increment end iterator!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 141, __PRETTY_FUNCTION__));
    U = U->getNext();
    return *this;
  }

  use_iterator_impl operator++(int) { // Postincrement
    auto tmp = *this;
    ++*this;
    return tmp;
  }

  UseT &operator*() const {
    assert(U && "Cannot dereference end iterator!")((U && "Cannot dereference end iterator!") ? static_cast
<void> (0) : __assert_fail ("U && \"Cannot dereference end iterator!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 153, __PRETTY_FUNCTION__));
    return *U;
  }

  UseT *operator->() const { return &operator*(); }

  operator use_iterator_impl<const UseT>() const {
    return use_iterator_impl<const UseT>(U);
  }
};

template <typename UserTy> // UserTy == 'User' or 'const User'
class user_iterator_impl
    : public std::iterator<std::forward_iterator_tag, UserTy *> {
  use_iterator_impl<Use> UI;
  explicit user_iterator_impl(Use *U) : UI(U) {}
  friend class Value;

public:
  user_iterator_impl() = default;

  bool operator==(const user_iterator_impl &x) const { return UI == x.UI; }
  bool operator!=(const user_iterator_impl &x) const { return !operator==(x); }

  /// Returns true if this iterator is equal to user_end() on the value.
  bool atEnd() const { return *this == user_iterator_impl(); }

  user_iterator_impl &operator++() { // Preincrement
    ++UI;
    return *this;
  }

  user_iterator_impl operator++(int) { // Postincrement
    auto tmp = *this;
    ++*this;
    return tmp;
  }

  // Retrieve a pointer to the current User.
  UserTy *operator*() const {
    return UI->getUser();
  }

  UserTy *operator->() const { return operator*(); }

  operator user_iterator_impl<const UserTy>() const {
    return user_iterator_impl<const UserTy>(*UI);
  }

  Use &getUse() const { return *UI; }
};

205protected:
Value(Type *Ty, unsigned scid);

/// Value's destructor should be virtual by design, but that would require
/// that Value and all of its subclasses have a vtable that effectively
/// duplicates the information in the value ID. As a size optimization, the
/// destructor has been protected, and the caller should manually call
/// deleteValue.
~Value(); // Use deleteValue() to delete a generic Value.

215public:
Value(const Value &) = delete;
Value &operator=(const Value &) = delete;

/// Delete a pointer to a generic Value.
void deleteValue();

/// Support for debugging, callable in GDB: V->dump()
void dump() const;

/// Implement operator<< on Value.
/// @{
void print(raw_ostream &O, bool IsForDebug = false) const;
void print(raw_ostream &O, ModuleSlotTracker &MST,
           bool IsForDebug = false) const;
/// @}

/// Print the name of this Value out to the specified raw_ostream.
///
/// This is useful when you just want to print 'int %reg126', not the
/// instruction that generated it. If you specify a Module for context, then
/// even constanst get pretty-printed; for example, the type of a null
/// pointer is printed symbolically.
/// @{
void printAsOperand(raw_ostream &O, bool PrintType = true,
                    const Module *M = nullptr) const;
void printAsOperand(raw_ostream &O, bool PrintType,
                    ModuleSlotTracker &MST) const;
/// @}

/// All values are typed, get the type of this value.
Type *getType() const { return VTy; }

/// All values hold a context through their type.
LLVMContext &getContext() const;

// All values can potentially be named.
bool hasName() const { return HasName; }
ValueName *getValueName() const;
void setValueName(ValueName *VN);

256private:
void destroyValueName();
enum class ReplaceMetadataUses { No, Yes };
void doRAUW(Value *New, ReplaceMetadataUses);
void setNameImpl(const Twine &Name);

262public:
/// Return a constant reference to the value's name.
///
/// This guaranteed to return the same reference as long as the value is not
/// modified.  If the value has a name, this does a hashtable lookup, so it's
/// not free.
StringRef getName() const;

/// Change the name of the value.
///
/// Choose a new unique name if the provided name is taken.
///
/// \param Name The new name; or "" if the value's name should be removed.
void setName(const Twine &Name);

/// Transfer the name from V to this value.
///
/// After taking V's name, sets V's name to empty.
///
/// \note It is an error to call V->takeName(V).
void takeName(Value *V);

284#ifndef NDEBUG
std::string getNameOrAsOperand() const;
286#endif

/// Change all uses of this to point to a new Value.
///
/// Go through the uses list for this definition and make each use point to
/// "V" instead of "this".  After this completes, 'this's use list is
/// guaranteed to be empty.
void replaceAllUsesWith(Value *V);

/// Change non-metadata uses of this to point to a new Value.
///
/// Go through the uses list for this definition and make each use point to
/// "V" instead of "this". This function skips metadata entries in the list.
void replaceNonMetadataUsesWith(Value *V);

/// Go through the uses list for this definition and make each use point
/// to "V" if the callback ShouldReplace returns true for the given Use.
/// Unlike replaceAllUsesWith() this function does not support basic block
/// values or constant users.
void replaceUsesWithIf(Value *New,
                       llvm::function_ref<bool(Use &U)> ShouldReplace) {
  assert(New && "Value::replaceUsesWithIf(<null>) is invalid!")((New && "Value::replaceUsesWithIf(<null>) is invalid!"
) ? static_cast<void> (0) : __assert_fail ("New && \"Value::replaceUsesWithIf(<null>) is invalid!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 307, __PRETTY_FUNCTION__));
  assert(New->getType() == getType() &&((New->getType() == getType() && "replaceUses of value with new value of different type!"
) ? static_cast<void> (0) : __assert_fail ("New->getType() == getType() && \"replaceUses of value with new value of different type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 309, __PRETTY_FUNCTION__))
         "replaceUses of value with new value of different type!")((New->getType() == getType() && "replaceUses of value with new value of different type!"
) ? static_cast<void> (0) : __assert_fail ("New->getType() == getType() && \"replaceUses of value with new value of different type!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 309, __PRETTY_FUNCTION__));

  for (use_iterator UI = use_begin(), E = use_end(); UI != E;) {
    Use &U = *UI;
    ++UI;
    if (!ShouldReplace(U))
      continue;
    U.set(New);
  }
}

/// replaceUsesOutsideBlock - Go through the uses list for this definition and
/// make each use point to "V" instead of "this" when the use is outside the
/// block. 'This's use list is expected to have at least one element.
/// Unlike replaceAllUsesWith() this function does not support basic block
/// values or constant users.
void replaceUsesOutsideBlock(Value *V, BasicBlock *BB);

//----------------------------------------------------------------------
// Methods for handling the chain of uses of this Value.
//
// Materializing a function can introduce new uses, so these methods come in
// two variants:
// The methods that start with materialized_ check the uses that are
// currently known given which functions are materialized. Be very careful
// when using them since you might not get all uses.
// The methods that don't start with materialized_ assert that modules is
// fully materialized.
void assertModuleIsMaterializedImpl() const;
// This indirection exists so we can keep assertModuleIsMaterializedImpl()
// around in release builds of Value.cpp to be linked with other code built
// in debug mode. But this avoids calling it in any of the release built code.
void assertModuleIsMaterialized() const {
342#ifndef NDEBUG
  assertModuleIsMaterializedImpl();
344#endif
}

bool use_empty() const {
  assertModuleIsMaterialized();
  return UseList == nullptr;
}

bool materialized_use_empty() const {
  return UseList == nullptr;
}

using use_iterator = use_iterator_impl<Use>;
using const_use_iterator = use_iterator_impl<const Use>;

use_iterator materialized_use_begin() { return use_iterator(UseList); }
const_use_iterator materialized_use_begin() const {
  return const_use_iterator(UseList);
}
use_iterator use_begin() {
  assertModuleIsMaterialized();
  return materialized_use_begin();
}
const_use_iterator use_begin() const {
  assertModuleIsMaterialized();
  return materialized_use_begin();
}
use_iterator use_end() { return use_iterator(); }
const_use_iterator use_end() const { return const_use_iterator(); }
iterator_range<use_iterator> materialized_uses() {
  return make_range(materialized_use_begin(), use_end());
}
iterator_range<const_use_iterator> materialized_uses() const {
  return make_range(materialized_use_begin(), use_end());
}
iterator_range<use_iterator> uses() {
  assertModuleIsMaterialized();
  return materialized_uses();
}
iterator_range<const_use_iterator> uses() const {
  assertModuleIsMaterialized();
  return materialized_uses();
}

bool user_empty() const {
  assertModuleIsMaterialized();
  return UseList == nullptr;
}

using user_iterator = user_iterator_impl<User>;
using const_user_iterator = user_iterator_impl<const User>;

user_iterator materialized_user_begin() { return user_iterator(UseList); }
const_user_iterator materialized_user_begin() const {
  return const_user_iterator(UseList);
}
user_iterator user_begin() {
  assertModuleIsMaterialized();
  return materialized_user_begin();
}
const_user_iterator user_begin() const {
  assertModuleIsMaterialized();
  return materialized_user_begin();
}
user_iterator user_end() { return user_iterator(); }
const_user_iterator user_end() const { return const_user_iterator(); }
User *user_back() {
  assertModuleIsMaterialized();
  return *materialized_user_begin();
}
const User *user_back() const {
  assertModuleIsMaterialized();
  return *materialized_user_begin();
}
iterator_range<user_iterator> materialized_users() {
  return make_range(materialized_user_begin(), user_end());
}
iterator_range<const_user_iterator> materialized_users() const {
  return make_range(materialized_user_begin(), user_end());
}
iterator_range<user_iterator> users() {
  assertModuleIsMaterialized();
  return materialized_users();
}
iterator_range<const_user_iterator> users() const {
  assertModuleIsMaterialized();
  return materialized_users();
}

/// Return true if there is exactly one use of this value.
///
/// This is specialized because it is a common request and does not require
/// traversing the whole use list.
bool hasOneUse() const { return hasSingleElement(uses()); }
13
←
Calling 'hasSingleElement<llvm::iterator_range<llvm::Value::use_iterator_impl<const llvm::Use>>>'→
16
←
Returning from 'hasSingleElement<llvm::iterator_range<llvm::Value::use_iterator_impl<const llvm::Use>>>'→
17
←
Returning value, which participates in a condition later→

/// Return true if this Value has exactly N uses.
bool hasNUses(unsigned N) const;

/// Return true if this value has N uses or more.
///
/// This is logically equivalent to getNumUses() >= N.
bool hasNUsesOrMore(unsigned N) const;

/// Return true if there is exactly one user of this value.
///
/// Note that this is not the same as "has one use". If a value has one use,
/// then there certainly is a single user. But if value has several uses,
/// it is possible that all uses are in a single user, or not.
///
/// This check is potentially costly, since it requires traversing,
/// in the worst case, the whole use list of a value.
bool hasOneUser() const;

/// Return true if there is exactly one use of this value that cannot be
/// dropped.
///
/// This is specialized because it is a common request and does not require
/// traversing the whole use list.
Use *getSingleUndroppableUse();

/// Return true if there this value.
///
/// This is specialized because it is a common request and does not require
/// traversing the whole use list.
bool hasNUndroppableUses(unsigned N) const;

/// Return true if this value has N uses or more.
///
/// This is logically equivalent to getNumUses() >= N.
bool hasNUndroppableUsesOrMore(unsigned N) const;

/// Remove every uses that can safely be removed.
///
/// This will remove for example uses in llvm.assume.
/// This should be used when performing want to perform a tranformation but
/// some Droppable uses pervent it.
/// This function optionally takes a filter to only remove some droppable
/// uses.
void dropDroppableUses(llvm::function_ref<bool(const Use *)> ShouldDrop =
                           [](const Use *) { return true; });

/// Remove every use of this value in \p User that can safely be removed.
void dropDroppableUsesIn(User &Usr);

/// Remove the droppable use \p U.
static void dropDroppableUse(Use &U);

/// Check if this value is used in the specified basic block.
bool isUsedInBasicBlock(const BasicBlock *BB) const;

/// This method computes the number of uses of this Value.
///
/// This is a linear time operation.  Use hasOneUse, hasNUses, or
/// hasNUsesOrMore to check for specific values.
unsigned getNumUses() const;

/// This method should only be used by the Use class.
void addUse(Use &U) { U.addToList(&UseList); }

/// Concrete subclass of this.
///
/// An enumeration for keeping track of the concrete subclass of Value that
/// is actually instantiated. Values of this enumeration are kept in the
/// Value classes SubclassID field. They are used for concrete type
/// identification.
enum ValueTy {
510#define HANDLE_VALUE(Name) Name##Val,
511#include "llvm/IR/Value.def"

  // Markers:
514#define HANDLE_CONSTANT_MARKER(Marker, Constant) Marker = Constant##Val,
515#include "llvm/IR/Value.def"
};

/// Return an ID for the concrete type of this object.
///
/// This is used to implement the classof checks.  This should not be used
/// for any other purpose, as the values may change as LLVM evolves.  Also,
/// note that for instructions, the Instruction's opcode is added to
/// InstructionVal. So this means three things:
/// # there is no value with code InstructionVal (no opcode==0).
/// # there are more possible values for the value type than in ValueTy enum.
/// # the InstructionVal enumerator must be the highest valued enumerator in
///   the ValueTy enum.
unsigned getValueID() const {
  return SubclassID;
}

/// Return the raw optional flags value contained in this value.
///
/// This should only be used when testing two Values for equivalence.
unsigned getRawSubclassOptionalData() const {
  return SubclassOptionalData;
}

/// Clear the optional flags contained in this value.
void clearSubclassOptionalData() {
  SubclassOptionalData = 0;
}

/// Check the optional flags for equality.
bool hasSameSubclassOptionalData(const Value *V) const {
  return SubclassOptionalData == V->SubclassOptionalData;
}

/// Return true if there is a value handle associated with this value.
bool hasValueHandle() const { return HasValueHandle; }

/// Return true if there is metadata referencing this value.
bool isUsedByMetadata() const { return IsUsedByMD; }

555protected:
/// Get the current metadata attachments for the given kind, if any.
///
/// These functions require that the value have at most a single attachment
/// of the given kind, and return \c nullptr if such an attachment is missing.
/// @{
MDNode *getMetadata(unsigned KindID) const;
MDNode *getMetadata(StringRef Kind) const;
/// @}

/// Appends all attachments with the given ID to \c MDs in insertion order.
/// If the Value has no attachments with the given ID, or if ID is invalid,
/// leaves MDs unchanged.
/// @{
void getMetadata(unsigned KindID, SmallVectorImpl<MDNode *> &MDs) const;
void getMetadata(StringRef Kind, SmallVectorImpl<MDNode *> &MDs) const;
/// @}

/// Appends all metadata attached to this value to \c MDs, sorting by
/// KindID. The first element of each pair returned is the KindID, the second
/// element is the metadata value. Attachments with the same ID appear in
/// insertion order.
void
getAllMetadata(SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const;

/// Return true if this value has any metadata attached to it.
bool hasMetadata() const { return (bool)HasMetadata; }

/// Return true if this value has the given type of metadata attached.
/// @{
bool hasMetadata(unsigned KindID) const {
  return getMetadata(KindID) != nullptr;
}
bool hasMetadata(StringRef Kind) const {
  return getMetadata(Kind) != nullptr;
}
/// @}

/// Set a particular kind of metadata attachment.
///
/// Sets the given attachment to \c MD, erasing it if \c MD is \c nullptr or
/// replacing it if it already exists.
/// @{
void setMetadata(unsigned KindID, MDNode *Node);
void setMetadata(StringRef Kind, MDNode *Node);
/// @}

/// Add a metadata attachment.
/// @{
void addMetadata(unsigned KindID, MDNode &MD);
void addMetadata(StringRef Kind, MDNode &MD);
/// @}

/// Erase all metadata attachments with the given kind.
///
/// \returns true if any metadata was removed.
bool eraseMetadata(unsigned KindID);

/// Erase all metadata attached to this Value.
void clearMetadata();

616public:
/// Return true if this value is a swifterror value.
///
/// swifterror values can be either a function argument or an alloca with a
/// swifterror attribute.
bool isSwiftError() const;

/// Strip off pointer casts, all-zero GEPs and address space casts.
///
/// Returns the original uncasted value.  If this is called on a non-pointer
/// value, it returns 'this'.
const Value *stripPointerCasts() const;
Value *stripPointerCasts() {
  return const_cast<Value *>(
      static_cast<const Value *>(this)->stripPointerCasts());
}

/// Strip off pointer casts, all-zero GEPs, address space casts, and aliases.
///
/// Returns the original uncasted value.  If this is called on a non-pointer
/// value, it returns 'this'.
const Value *stripPointerCastsAndAliases() const;
Value *stripPointerCastsAndAliases() {
  return const_cast<Value *>(
      static_cast<const Value *>(this)->stripPointerCastsAndAliases());
}

/// Strip off pointer casts, all-zero GEPs and address space casts
/// but ensures the representation of the result stays the same.
///
/// Returns the original uncasted value with the same representation. If this
/// is called on a non-pointer value, it returns 'this'.
const Value *stripPointerCastsSameRepresentation() const;
Value *stripPointerCastsSameRepresentation() {
  return const_cast<Value *>(static_cast<const Value *>(this)
                                 ->stripPointerCastsSameRepresentation());
}

/// Strip off pointer casts, all-zero GEPs and invariant group info.
///
/// Returns the original uncasted value.  If this is called on a non-pointer
/// value, it returns 'this'. This function should be used only in
/// Alias analysis.
const Value *stripPointerCastsAndInvariantGroups() const;
Value *stripPointerCastsAndInvariantGroups() {
  return const_cast<Value *>(static_cast<const Value *>(this)
                                 ->stripPointerCastsAndInvariantGroups());
}

/// Strip off pointer casts and all-constant inbounds GEPs.
///
/// Returns the original pointer value.  If this is called on a non-pointer
/// value, it returns 'this'.
const Value *stripInBoundsConstantOffsets() const;
Value *stripInBoundsConstantOffsets() {
  return const_cast<Value *>(
            static_cast<const Value *>(this)->stripInBoundsConstantOffsets());
}

/// Accumulate the constant offset this value has compared to a base pointer.
/// Only 'getelementptr' instructions (GEPs) are accumulated but other
/// instructions, e.g., casts, are stripped away as well.
/// The accumulated constant offset is added to \p Offset and the base
/// pointer is returned.
///
/// The APInt \p Offset has to have a bit-width equal to the IntPtr type for
/// the address space of 'this' pointer value, e.g., use
/// DataLayout::getIndexTypeSizeInBits(Ty).
///
/// If \p AllowNonInbounds is true, offsets in GEPs are stripped and
/// accumulated even if the GEP is not "inbounds".
///
/// If \p ExternalAnalysis is provided it will be used to calculate a offset
/// when a operand of GEP is not constant.
/// For example, for a value \p ExternalAnalysis might try to calculate a
/// lower bound. If \p ExternalAnalysis is successful, it should return true.
///
/// If this is called on a non-pointer value, it returns 'this' and the
/// \p Offset is not modified.
///
/// Note that this function will never return a nullptr. It will also never
/// manipulate the \p Offset in a way that would not match the difference
/// between the underlying value and the returned one. Thus, if no constant
/// offset was found, the returned value is the underlying one and \p Offset
/// is unchanged.
const Value *stripAndAccumulateConstantOffsets(
    const DataLayout &DL, APInt &Offset, bool AllowNonInbounds,
    function_ref<bool(Value &Value, APInt &Offset)> ExternalAnalysis =
        nullptr) const;
Value *stripAndAccumulateConstantOffsets(const DataLayout &DL, APInt &Offset,
                                         bool AllowNonInbounds) {
  return const_cast<Value *>(
      static_cast<const Value *>(this)->stripAndAccumulateConstantOffsets(
          DL, Offset, AllowNonInbounds));
}

/// This is a wrapper around stripAndAccumulateConstantOffsets with the
/// in-bounds requirement set to false.
const Value *stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL,
                                                       APInt &Offset) const {
  return stripAndAccumulateConstantOffsets(DL, Offset,
                                           /* AllowNonInbounds */ false);
}
Value *stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL,
                                                 APInt &Offset) {
  return stripAndAccumulateConstantOffsets(DL, Offset,
                                           /* AllowNonInbounds */ false);
}

/// Strip off pointer casts and inbounds GEPs.
///
/// Returns the original pointer value.  If this is called on a non-pointer
/// value, it returns 'this'.
const Value *stripInBoundsOffsets(function_ref<void(const Value *)> Func =
                                      [](const Value *) {}) const;
inline Value *stripInBoundsOffsets(function_ref<void(const Value *)> Func =
                                [](const Value *) {}) {
  return const_cast<Value *>(
      static_cast<const Value *>(this)->stripInBoundsOffsets(Func));
}

/// Returns the number of bytes known to be dereferenceable for the
/// pointer value.
///
/// If CanBeNull is set by this function the pointer can either be null or be
/// dereferenceable up to the returned number of bytes.
uint64_t getPointerDereferenceableBytes(const DataLayout &DL,
                                        bool &CanBeNull) const;

/// Returns an alignment of the pointer value.
///
/// Returns an alignment which is either specified explicitly, e.g. via
/// align attribute of a function argument, or guaranteed by DataLayout.
Align getPointerAlignment(const DataLayout &DL) const;

/// Translate PHI node to its predecessor from the given basic block.
///
/// If this value is a PHI node with CurBB as its parent, return the value in
/// the PHI node corresponding to PredBB.  If not, return ourself.  This is
/// useful if you want to know the value something has in a predecessor
/// block.
const Value *DoPHITranslation(const BasicBlock *CurBB,
                              const BasicBlock *PredBB) const;
Value *DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB) {
  return const_cast<Value *>(
           static_cast<const Value *>(this)->DoPHITranslation(CurBB, PredBB));
}

/// The maximum alignment for instructions.
///
/// This is the greatest alignment value supported by load, store, and alloca
/// instructions, and global values.
static const unsigned MaxAlignmentExponent = 29;
static const unsigned MaximumAlignment = 1u << MaxAlignmentExponent;

/// Mutate the type of this Value to be of the specified type.
///
/// Note that this is an extremely dangerous operation which can create
/// completely invalid IR very easily.  It is strongly recommended that you
/// recreate IR objects with the right types instead of mutating them in
/// place.
void mutateType(Type *Ty) {
  VTy = Ty;
}

/// Sort the use-list.
///
/// Sorts the Value's use-list by Cmp using a stable mergesort.  Cmp is
/// expected to compare two \a Use references.
template <class Compare> void sortUseList(Compare Cmp);

/// Reverse the use-list.
void reverseUseList();

790private:
/// Merge two lists together.
///
/// Merges \c L and \c R using \c Cmp.  To enable stable sorts, always pushes
/// "equal" items from L before items from R.
///
/// \return the first element in the list.
///
/// \note Completely ignores \a Use::Prev (doesn't read, doesn't update).
template <class Compare>
static Use *mergeUseLists(Use *L, Use *R, Compare Cmp) {
  Use *Merged;
  Use **Next = &Merged;

  while (true) {
    if (!L) {
      *Next = R;
      break;
    }
    if (!R) {
      *Next = L;
      break;
    }
    if (Cmp(*R, *L)) {
      *Next = R;
      Next = &R->Next;
      R = R->Next;
    } else {
      *Next = L;
      Next = &L->Next;
      L = L->Next;
    }
  }

  return Merged;
}

827protected:
unsigned short getSubclassDataFromValue() const { return SubclassData; }
void setValueSubclassData(unsigned short D) { SubclassData = D; }
830};

832struct ValueDeleter { void operator()(Value *V) { V->deleteValue(); } };

834/// Use this instead of std::unique_ptr<Value> or std::unique_ptr<Instruction>.
835/// Those don't work because Value and Instruction's destructors are protected,
836/// aren't virtual, and won't destroy the complete object.
837using unique_value = std::unique_ptr<Value, ValueDeleter>;

839inline raw_ostream &operator<<(raw_ostream &OS, const Value &V) {
V.print(OS);
return OS;
842}

844void Use::set(Value *V) {
if (Val) removeFromList();
Val = V;
if (V) V->addUse(*this);
848}

850Value *Use::operator=(Value *RHS) {
set(RHS);
return RHS;
853}

855const Use &Use::operator=(const Use &RHS) {
set(RHS.Val);
return *this;
858}

860template <class Compare> void Value::sortUseList(Compare Cmp) {
if (!UseList || !UseList->Next)
  // No need to sort 0 or 1 uses.
  return;

// Note: this function completely ignores Prev pointers until the end when
// they're fixed en masse.

// Create a binomial vector of sorted lists, visiting uses one at a time and
// merging lists as necessary.
const unsigned MaxSlots = 32;
Use *Slots[MaxSlots];

// Collect the first use, turning it into a single-item list.
Use *Next = UseList->Next;
UseList->Next = nullptr;
unsigned NumSlots = 1;
Slots[0] = UseList;

// Collect all but the last use.
while (Next->Next) {
  Use *Current = Next;
  Next = Current->Next;

  // Turn Current into a single-item list.
  Current->Next = nullptr;

  // Save Current in the first available slot, merging on collisions.
  unsigned I;
  for (I = 0; I < NumSlots; ++I) {
    if (!Slots[I])
      break;

    // Merge two lists, doubling the size of Current and emptying slot I.
    //
    // Since the uses in Slots[I] originally preceded those in Current, send
    // Slots[I] in as the left parameter to maintain a stable sort.
    Current = mergeUseLists(Slots[I], Current, Cmp);
    Slots[I] = nullptr;
  }
  // Check if this is a new slot.
  if (I == NumSlots) {
    ++NumSlots;
    assert(NumSlots <= MaxSlots && "Use list bigger than 2^32")((NumSlots <= MaxSlots && "Use list bigger than 2^32"
) ? static_cast<void> (0) : __assert_fail ("NumSlots <= MaxSlots && \"Use list bigger than 2^32\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 903, __PRETTY_FUNCTION__));
  }

  // Found an open slot.
  Slots[I] = Current;
}

// Merge all the lists together.
assert(Next && "Expected one more Use")((Next && "Expected one more Use") ? static_cast<void
> (0) : __assert_fail ("Next && \"Expected one more Use\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 911, __PRETTY_FUNCTION__));
assert(!Next->Next && "Expected only one Use")((!Next->Next && "Expected only one Use") ? static_cast
<void> (0) : __assert_fail ("!Next->Next && \"Expected only one Use\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/IR/Value.h"
, 912, __PRETTY_FUNCTION__));
UseList = Next;
for (unsigned I = 0; I < NumSlots; ++I)
  if (Slots[I])
    // Since the uses in Slots[I] originally preceded those in UseList, send
    // Slots[I] in as the left parameter to maintain a stable sort.
    UseList = mergeUseLists(Slots[I], UseList, Cmp);

// Fix the Prev pointers.
for (Use *I = UseList, **Prev = &UseList; I; I = I->Next) {
  I->Prev = Prev;
  Prev = &I->Next;
}
925}

927// isa - Provide some specializations of isa so that we don't have to include
928// the subtype header files to test to see if the value is a subclass...
929//
930template <> struct isa_impl<Constant, Value> {
static inline bool doit(const Value &Val) {
  static_assert(Value::ConstantFirstVal == 0, "Val.getValueID() >= Value::ConstantFirstVal");
  return Val.getValueID() <= Value::ConstantLastVal;
}
935};

937template <> struct isa_impl<ConstantData, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() >= Value::ConstantDataFirstVal &&
         Val.getValueID() <= Value::ConstantDataLastVal;
}
942};

944template <> struct isa_impl<ConstantAggregate, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() >= Value::ConstantAggregateFirstVal &&
         Val.getValueID() <= Value::ConstantAggregateLastVal;
}
949};

951template <> struct isa_impl<Argument, Value> {
static inline bool doit (const Value &Val) {
  return Val.getValueID() == Value::ArgumentVal;
}
955};

957template <> struct isa_impl<InlineAsm, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() == Value::InlineAsmVal;
}
961};

963template <> struct isa_impl<Instruction, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() >= Value::InstructionVal;
}
967};

969template <> struct isa_impl<BasicBlock, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() == Value::BasicBlockVal;
}
973};

975template <> struct isa_impl<Function, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() == Value::FunctionVal;
}
979};

981template <> struct isa_impl<GlobalVariable, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() == Value::GlobalVariableVal;
}
985};

987template <> struct isa_impl<GlobalAlias, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() == Value::GlobalAliasVal;
}
991};

993template <> struct isa_impl<GlobalIFunc, Value> {
static inline bool doit(const Value &Val) {
  return Val.getValueID() == Value::GlobalIFuncVal;
}
997};

999template <> struct isa_impl<GlobalIndirectSymbol, Value> {
static inline bool doit(const Value &Val) {
  return isa<GlobalAlias>(Val) || isa<GlobalIFunc>(Val);
}
1003};

1005template <> struct isa_impl<GlobalValue, Value> {
static inline bool doit(const Value &Val) {
  return isa<GlobalObject>(Val) || isa<GlobalIndirectSymbol>(Val);
}
1009};

1011template <> struct isa_impl<GlobalObject, Value> {
static inline bool doit(const Value &Val) {
  return isa<GlobalVariable>(Val) || isa<Function>(Val);
}
1015};

1017// Create wrappers for C Binding types (see CBindingWrapping.h).
1018DEFINE_ISA_CONVERSION_FUNCTIONS(Value, LLVMValueRef)inline Value *unwrap(LLVMValueRef P) { return reinterpret_cast
<Value*>(P); } inline LLVMValueRef wrap(const Value *P)
 { return reinterpret_cast<LLVMValueRef>(const_cast<
Value*>(P)); } template<typename T> inline T *unwrap
(LLVMValueRef P) { return cast<T>(unwrap(P)); }

1020// Specialized opaque value conversions.
1021inline Value **unwrap(LLVMValueRef *Vals) {
return reinterpret_cast<Value**>(Vals);
1023}

1025template<typename T>
1026inline T **unwrap(LLVMValueRef *Vals, unsigned Length) {
1027#ifndef NDEBUG
for (LLVMValueRef *I = Vals, *E = Vals + Length; I != E; ++I)
  unwrap<T>(*I); // For side effect of calling assert on invalid usage.
1030#endif
(void)Length;
return reinterpret_cast<T**>(Vals);
1033}

1035inline LLVMValueRef *wrap(const Value **Vals) {
return reinterpret_cast<LLVMValueRef*>(const_cast<Value**>(Vals));
1037}

1039} // end namespace llvm

1041#endif // LLVM_IR_VALUE_H

←

/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h

→

1//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file contains some templates that are useful if you are working with the
10// STL at all.
11//
12// No library is required when using these functions.
13//
14//===----------------------------------------------------------------------===//
15 
16#ifndef LLVM_ADT_STLEXTRAS_H
17#define LLVM_ADT_STLEXTRAS_H
18 
19#include "llvm/ADT/Optional.h"
20#include "llvm/ADT/iterator.h"
21#include "llvm/ADT/iterator_range.h"
22#include "llvm/Config/abi-breaking.h"
23#include "llvm/Support/ErrorHandling.h"
24#include <algorithm>
25#include <cassert>
26#include <cstddef>
27#include <cstdint>
28#include <cstdlib>
29#include <functional>
30#include <initializer_list>
31#include <iterator>
32#include <limits>
33#include <memory>
34#include <tuple>
35#include <type_traits>
36#include <utility>
37 
38#ifdef EXPENSIVE_CHECKS
39#include <random> // for std::mt19937
40#endif
41 
42namespace llvm {
43 
44// Only used by compiler if both template types are the same.  Useful when
45// using SFINAE to test for the existence of member functions.
46template <typename T, T> struct SameType;
47 
48namespace detail {
49 
50template <typename RangeT>
51using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
52 
53template <typename RangeT>
54using ValueOfRange = typename std::remove_reference<decltype(
55    *std::begin(std::declval<RangeT &>()))>::type;
56 
57} // end namespace detail
58 
59//===----------------------------------------------------------------------===//
60//     Extra additions to <type_traits>
61//===----------------------------------------------------------------------===//
62 
63template <typename T>
64struct negation : std::integral_constant<bool, !bool(T::value)> {};
65 
66template <typename...> struct conjunction : std::true_type {};
67template <typename B1> struct conjunction<B1> : B1 {};
68template <typename B1, typename... Bn>
69struct conjunction<B1, Bn...>
70    : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {};
71 
72template <typename T> struct make_const_ptr {
73  using type =
74      typename std::add_pointer<typename std::add_const<T>::type>::type;
75};
76 
77template <typename T> struct make_const_ref {
78  using type = typename std::add_lvalue_reference<
79      typename std::add_const<T>::type>::type;
80};
81 
82/// Utilities for detecting if a given trait holds for some set of arguments
83/// 'Args'. For example, the given trait could be used to detect if a given type
84/// has a copy assignment operator:
85///   template<class T>
86///   using has_copy_assign_t = decltype(std::declval<T&>()
87///                                                 = std::declval<const T&>());
88///   bool fooHasCopyAssign = is_detected<has_copy_assign_t, FooClass>::value;
89namespace detail {
90template <typename...> using void_t = void;
91template <class, template <class...> class Op, class... Args> struct detector {
92  using value_t = std::false_type;
93};
94template <template <class...> class Op, class... Args>
95struct detector<void_t<Op<Args...>>, Op, Args...> {
96  using value_t = std::true_type;
97};
98} // end namespace detail
99 
100template <template <class...> class Op, class... Args>
101using is_detected = typename detail::detector<void, Op, Args...>::value_t;
102 
103/// Check if a Callable type can be invoked with the given set of arg types.
104namespace detail {
105template <typename Callable, typename... Args>
106using is_invocable =
107    decltype(std::declval<Callable &>()(std::declval<Args>()...));
108} // namespace detail
109 
110template <typename Callable, typename... Args>
111using is_invocable = is_detected<detail::is_invocable, Callable, Args...>;
112 
113/// This class provides various trait information about a callable object.
114///   * To access the number of arguments: Traits::num_args
115///   * To access the type of an argument: Traits::arg_t<Index>
116///   * To access the type of the result:  Traits::result_t
117template <typename T, bool isClass = std::is_class<T>::value>
118struct function_traits : public function_traits<decltype(&T::operator())> {};
119 
120/// Overload for class function types.
121template <typename ClassType, typename ReturnType, typename... Args>
122struct function_traits<ReturnType (ClassType::*)(Args...) const, false> {
123  /// The number of arguments to this function.
124  enum { num_args = sizeof...(Args) };
125 
126  /// The result type of this function.
127  using result_t = ReturnType;
128 
129  /// The type of an argument to this function.
130  template <size_t Index>
131  using arg_t = typename std::tuple_element<Index, std::tuple<Args...>>::type;
132};
133/// Overload for class function types.
134template <typename ClassType, typename ReturnType, typename... Args>
135struct function_traits<ReturnType (ClassType::*)(Args...), false>
136    : function_traits<ReturnType (ClassType::*)(Args...) const> {};
137/// Overload for non-class function types.
138template <typename ReturnType, typename... Args>
139struct function_traits<ReturnType (*)(Args...), false> {
140  /// The number of arguments to this function.
141  enum { num_args = sizeof...(Args) };
142 
143  /// The result type of this function.
144  using result_t = ReturnType;
145 
146  /// The type of an argument to this function.
147  template <size_t i>
148  using arg_t = typename std::tuple_element<i, std::tuple<Args...>>::type;
149};
150/// Overload for non-class function type references.
151template <typename ReturnType, typename... Args>
152struct function_traits<ReturnType (&)(Args...), false>
153    : public function_traits<ReturnType (*)(Args...)> {};
154 
155//===----------------------------------------------------------------------===//
156//     Extra additions to <functional>
157//===----------------------------------------------------------------------===//
158 
159template <class Ty> struct identity {
160  using argument_type = Ty;
161 
162  Ty &operator()(Ty &self) const {
163    return self;
164  }
165  const Ty &operator()(const Ty &self) const {
166    return self;
167  }
168};
169 
170/// An efficient, type-erasing, non-owning reference to a callable. This is
171/// intended for use as the type of a function parameter that is not used
172/// after the function in question returns.
173///
174/// This class does not own the callable, so it is not in general safe to store
175/// a function_ref.
176template<typename Fn> class function_ref;
177 
178template<typename Ret, typename ...Params>
179class function_ref<Ret(Params...)> {
180  Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
181  intptr_t callable;
182 
183  template<typename Callable>
184  static Ret callback_fn(intptr_t callable, Params ...params) {
185    return (*reinterpret_cast<Callable*>(callable))(
186        std::forward<Params>(params)...);
187  }
188 
189public:
190  function_ref() = default;
191  function_ref(std::nullptr_t) {}
192 
193  template <typename Callable>
194  function_ref(
195      Callable &&callable,
196      // This is not the copy-constructor.
197      std::enable_if_t<
198          !std::is_same<std::remove_cv_t<std::remove_reference_t<Callable>>,
199                        function_ref>::value> * = nullptr,
200      // Functor must be callable and return a suitable type.
201      std::enable_if_t<std::is_void<Ret>::value ||
202                       std::is_convertible<decltype(std::declval<Callable>()(
203                                               std::declval<Params>()...)),
204                                           Ret>::value> * = nullptr)
205      : callback(callback_fn<typename std::remove_reference<Callable>::type>),
206        callable(reinterpret_cast<intptr_t>(&callable)) {}
207 
208  Ret operator()(Params ...params) const {
209    return callback(callable, std::forward<Params>(params)...);
210  }
211 
212  explicit operator bool() const { return callback; }
213};
214 
215//===----------------------------------------------------------------------===//
216//     Extra additions to <iterator>
217//===----------------------------------------------------------------------===//
218 
219namespace adl_detail {
220 
221using std::begin;
222 
223template <typename ContainerTy>
224decltype(auto) adl_begin(ContainerTy &&container) {
225  return begin(std::forward<ContainerTy>(container));
226}
227 
228using std::end;
229 
230template <typename ContainerTy>
231decltype(auto) adl_end(ContainerTy &&container) {
232  return end(std::forward<ContainerTy>(container));
233}
234 
235using std::swap;
236 
237template <typename T>
238void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
239                                                       std::declval<T>()))) {
240  swap(std::forward<T>(lhs), std::forward<T>(rhs));
241}
242 
243} // end namespace adl_detail
244 
245template <typename ContainerTy>
246decltype(auto) adl_begin(ContainerTy &&container) {
247  return adl_detail::adl_begin(std::forward<ContainerTy>(container));
248}
249 
250template <typename ContainerTy>
251decltype(auto) adl_end(ContainerTy &&container) {
252  return adl_detail::adl_end(std::forward<ContainerTy>(container));
253}
254 
255template <typename T>
256void adl_swap(T &&lhs, T &&rhs) noexcept(
257    noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
258  adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
259}
260 
261/// Test whether \p RangeOrContainer is empty. Similar to C++17 std::empty.
262template <typename T>
263constexpr bool empty(const T &RangeOrContainer) {
264  return adl_begin(RangeOrContainer) == adl_end(RangeOrContainer);
265}
266 
267/// Returns true if the given container only contains a single element.
268template <typename ContainerTy> bool hasSingleElement(ContainerTy &&C) {
269  auto B = std::begin(C), E = std::end(C);
270  return B != E && std::next(B) == E;
14
←
Assuming the condition is true→
15
←
Returning value, which participates in a condition later→
271}
272 
273/// Return a range covering \p RangeOrContainer with the first N elements
274/// excluded.
275template <typename T> auto drop_begin(T &&RangeOrContainer, size_t N = 1) {
276  return make_range(std::next(adl_begin(RangeOrContainer), N),
277                    adl_end(RangeOrContainer));
278}
279 
280// mapped_iterator - This is a simple iterator adapter that causes a function to
281// be applied whenever operator* is invoked on the iterator.
282 
283template <typename ItTy, typename FuncTy,
284          typename FuncReturnTy =
285            decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
286class mapped_iterator
287    : public iterator_adaptor_base<
288             mapped_iterator<ItTy, FuncTy>, ItTy,
289             typename std::iterator_traits<ItTy>::iterator_category,
290             typename std::remove_reference<FuncReturnTy>::type> {
291public:
292  mapped_iterator(ItTy U, FuncTy F)
293    : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
294 
295  ItTy getCurrent() { return this->I; }
296 
297  FuncReturnTy operator*() const { return F(*this->I); }
298 
299private:
300  FuncTy F;
301};
302 
303// map_iterator - Provide a convenient way to create mapped_iterators, just like
304// make_pair is useful for creating pairs...
305template <class ItTy, class FuncTy>
306inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
307  return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
308}
309 
310template <class ContainerTy, class FuncTy>
311auto map_range(ContainerTy &&C, FuncTy F) {
312  return make_range(map_iterator(C.begin(), F), map_iterator(C.end(), F));
313}
314 
315/// Helper to determine if type T has a member called rbegin().
316template <typename Ty> class has_rbegin_impl {
317  using yes = char[1];
318  using no = char[2];
319 
320  template <typename Inner>
321  static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
322 
323  template <typename>
324  static no& test(...);
325 
326public:
327  static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
328};
329 
330/// Metafunction to determine if T& or T has a member called rbegin().
331template <typename Ty>
332struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
333};
334 
335// Returns an iterator_range over the given container which iterates in reverse.
336// Note that the container must have rbegin()/rend() methods for this to work.
337template <typename ContainerTy>
338auto reverse(ContainerTy &&C,
339             std::enable_if_t<has_rbegin<ContainerTy>::value> * = nullptr) {
340  return make_range(C.rbegin(), C.rend());
341}
342 
343// Returns a std::reverse_iterator wrapped around the given iterator.
344template <typename IteratorTy>
345std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
346  return std::reverse_iterator<IteratorTy>(It);
347}
348 
349// Returns an iterator_range over the given container which iterates in reverse.
350// Note that the container must have begin()/end() methods which return
351// bidirectional iterators for this to work.
352template <typename ContainerTy>
353auto reverse(ContainerTy &&C,
354             std::enable_if_t<!has_rbegin<ContainerTy>::value> * = nullptr) {
355  return make_range(llvm::make_reverse_iterator(std::end(C)),
356                    llvm::make_reverse_iterator(std::begin(C)));
357}
358 
359/// An iterator adaptor that filters the elements of given inner iterators.
360///
361/// The predicate parameter should be a callable object that accepts the wrapped
362/// iterator's reference type and returns a bool. When incrementing or
363/// decrementing the iterator, it will call the predicate on each element and
364/// skip any where it returns false.
365///
366/// \code
367///   int A[] = { 1, 2, 3, 4 };
368///   auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
369///   // R contains { 1, 3 }.
370/// \endcode
371///
372/// Note: filter_iterator_base implements support for forward iteration.
373/// filter_iterator_impl exists to provide support for bidirectional iteration,
374/// conditional on whether the wrapped iterator supports it.
375template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
376class filter_iterator_base
377    : public iterator_adaptor_base<
378          filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
379          WrappedIteratorT,
380          typename std::common_type<
381              IterTag, typename std::iterator_traits<
382                           WrappedIteratorT>::iterator_category>::type> {
383  using BaseT = iterator_adaptor_base<
384      filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
385      WrappedIteratorT,
386      typename std::common_type<
387          IterTag, typename std::iterator_traits<
388                       WrappedIteratorT>::iterator_category>::type>;
389 
390protected:
391  WrappedIteratorT End;
392  PredicateT Pred;
393 
394  void findNextValid() {
395    while (this->I != End && !Pred(*this->I))
396      BaseT::operator++();
397  }
398 
399  // Construct the iterator. The begin iterator needs to know where the end
400  // is, so that it can properly stop when it gets there. The end iterator only
401  // needs the predicate to support bidirectional iteration.
402  filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
403                       PredicateT Pred)
404      : BaseT(Begin), End(End), Pred(Pred) {
405    findNextValid();
406  }
407 
408public:
409  using BaseT::operator++;
410 
411  filter_iterator_base &operator++() {
412    BaseT::operator++();
413    findNextValid();
414    return *this;
415  }
416};
417 
418/// Specialization of filter_iterator_base for forward iteration only.
419template <typename WrappedIteratorT, typename PredicateT,
420          typename IterTag = std::forward_iterator_tag>
421class filter_iterator_impl
422    : public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
423  using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
424 
425public:
426  filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
427                       PredicateT Pred)
428      : BaseT(Begin, End, Pred) {}
429};
430 
431/// Specialization of filter_iterator_base for bidirectional iteration.
432template <typename WrappedIteratorT, typename PredicateT>
433class filter_iterator_impl<WrappedIteratorT, PredicateT,
434                           std::bidirectional_iterator_tag>
435    : public filter_iterator_base<WrappedIteratorT, PredicateT,
436                                  std::bidirectional_iterator_tag> {
437  using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
438                                     std::bidirectional_iterator_tag>;
439  void findPrevValid() {
440    while (!this->Pred(*this->I))
441      BaseT::operator--();
442  }
443 
444public:
445  using BaseT::operator--;
446 
447  filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
448                       PredicateT Pred)
449      : BaseT(Begin, End, Pred) {}
450 
451  filter_iterator_impl &operator--() {
452    BaseT::operator--();
453    findPrevValid();
454    return *this;
455  }
456};
457 
458namespace detail {
459 
460template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
461  using type = std::forward_iterator_tag;
462};
463 
464template <> struct fwd_or_bidi_tag_impl<true> {
465  using type = std::bidirectional_iterator_tag;
466};
467 
468/// Helper which sets its type member to forward_iterator_tag if the category
469/// of \p IterT does not derive from bidirectional_iterator_tag, and to
470/// bidirectional_iterator_tag otherwise.
471template <typename IterT> struct fwd_or_bidi_tag {
472  using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
473      std::bidirectional_iterator_tag,
474      typename std::iterator_traits<IterT>::iterator_category>::value>::type;
475};
476 
477} // namespace detail
478 
479/// Defines filter_iterator to a suitable specialization of
480/// filter_iterator_impl, based on the underlying iterator's category.
481template <typename WrappedIteratorT, typename PredicateT>
482using filter_iterator = filter_iterator_impl<
483    WrappedIteratorT, PredicateT,
484    typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
485 
486/// Convenience function that takes a range of elements and a predicate,
487/// and return a new filter_iterator range.
488///
489/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
490/// lifetime of that temporary is not kept by the returned range object, and the
491/// temporary is going to be dropped on the floor after the make_iterator_range
492/// full expression that contains this function call.
493template <typename RangeT, typename PredicateT>
494iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
495make_filter_range(RangeT &&Range, PredicateT Pred) {
496  using FilterIteratorT =
497      filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
498  return make_range(
499      FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
500                      std::end(std::forward<RangeT>(Range)), Pred),
501      FilterIteratorT(std::end(std::forward<RangeT>(Range)),
502                      std::end(std::forward<RangeT>(Range)), Pred));
503}
504 
505/// A pseudo-iterator adaptor that is designed to implement "early increment"
506/// style loops.
507///
508/// This is *not a normal iterator* and should almost never be used directly. It
509/// is intended primarily to be used with range based for loops and some range
510/// algorithms.
511///
512/// The iterator isn't quite an `OutputIterator` or an `InputIterator` but
513/// somewhere between them. The constraints of these iterators are:
514///
515/// - On construction or after being incremented, it is comparable and
516///   dereferencable. It is *not* incrementable.
517/// - After being dereferenced, it is neither comparable nor dereferencable, it
518///   is only incrementable.
519///
520/// This means you can only dereference the iterator once, and you can only
521/// increment it once between dereferences.
522template <typename WrappedIteratorT>
523class early_inc_iterator_impl
524    : public iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
525                                   WrappedIteratorT, std::input_iterator_tag> {
526  using BaseT =
527      iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
528                            WrappedIteratorT, std::input_iterator_tag>;
529 
530  using PointerT = typename std::iterator_traits<WrappedIteratorT>::pointer;
531 
532protected:
533#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
534  bool IsEarlyIncremented = false;
535#endif
536 
537public:
538  early_inc_iterator_impl(WrappedIteratorT I) : BaseT(I) {}
539 
540  using BaseT::operator*;
541  decltype(*std::declval<WrappedIteratorT>()) operator*() {
542#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
543    assert(!IsEarlyIncremented && "Cannot dereference twice!")((!IsEarlyIncremented && "Cannot dereference twice!")
 ? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot dereference twice!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 543, __PRETTY_FUNCTION__));
544    IsEarlyIncremented = true;
545#endif
546    return *(this->I)++;
547  }
548 
549  using BaseT::operator++;
550  early_inc_iterator_impl &operator++() {
551#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
552    assert(IsEarlyIncremented && "Cannot increment before dereferencing!")((IsEarlyIncremented && "Cannot increment before dereferencing!"
) ? static_cast<void> (0) : __assert_fail ("IsEarlyIncremented && \"Cannot increment before dereferencing!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 552, __PRETTY_FUNCTION__));
553    IsEarlyIncremented = false;
554#endif
555    return *this;
556  }
557 
558  friend bool operator==(const early_inc_iterator_impl &LHS,
559                         const early_inc_iterator_impl &RHS) {
560#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
561    assert(!LHS.IsEarlyIncremented && "Cannot compare after dereferencing!")((!LHS.IsEarlyIncremented && "Cannot compare after dereferencing!"
) ? static_cast<void> (0) : __assert_fail ("!LHS.IsEarlyIncremented && \"Cannot compare after dereferencing!\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 561, __PRETTY_FUNCTION__));
562#endif
563    return (const BaseT &)LHS == (const BaseT &)RHS;
564  }
565};
566 
567/// Make a range that does early increment to allow mutation of the underlying
568/// range without disrupting iteration.
569///
570/// The underlying iterator will be incremented immediately after it is
571/// dereferenced, allowing deletion of the current node or insertion of nodes to
572/// not disrupt iteration provided they do not invalidate the *next* iterator --
573/// the current iterator can be invalidated.
574///
575/// This requires a very exact pattern of use that is only really suitable to
576/// range based for loops and other range algorithms that explicitly guarantee
577/// to dereference exactly once each element, and to increment exactly once each
578/// element.
579template <typename RangeT>
580iterator_range<early_inc_iterator_impl<detail::IterOfRange<RangeT>>>
581make_early_inc_range(RangeT &&Range) {
582  using EarlyIncIteratorT =
583      early_inc_iterator_impl<detail::IterOfRange<RangeT>>;
584  return make_range(EarlyIncIteratorT(std::begin(std::forward<RangeT>(Range))),
585                    EarlyIncIteratorT(std::end(std::forward<RangeT>(Range))));
586}
587 
588// forward declarations required by zip_shortest/zip_first/zip_longest
589template <typename R, typename UnaryPredicate>
590bool all_of(R &&range, UnaryPredicate P);
591template <typename R, typename UnaryPredicate>
592bool any_of(R &&range, UnaryPredicate P);
593 
594namespace detail {
595 
596using std::declval;
597 
598// We have to alias this since inlining the actual type at the usage site
599// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
600template<typename... Iters> struct ZipTupleType {
601  using type = std::tuple<decltype(*declval<Iters>())...>;
602};
603 
604template <typename ZipType, typename... Iters>
605using zip_traits = iterator_facade_base<
606    ZipType, typename std::common_type<std::bidirectional_iterator_tag,
607                                       typename std::iterator_traits<
608                                           Iters>::iterator_category...>::type,
609    // ^ TODO: Implement random access methods.
610    typename ZipTupleType<Iters...>::type,
611    typename std::iterator_traits<typename std::tuple_element<
612        0, std::tuple<Iters...>>::type>::difference_type,
613    // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
614    // inner iterators have the same difference_type. It would fail if, for
615    // instance, the second field's difference_type were non-numeric while the
616    // first is.
617    typename ZipTupleType<Iters...>::type *,
618    typename ZipTupleType<Iters...>::type>;
619 
620template <typename ZipType, typename... Iters>
621struct zip_common : public zip_traits<ZipType, Iters...> {
622  using Base = zip_traits<ZipType, Iters...>;
623  using value_type = typename Base::value_type;
624 
625  std::tuple<Iters...> iterators;
626 
627protected:
628  template <size_t... Ns> value_type deref(std::index_sequence<Ns...>) const {
629    return value_type(*std::get<Ns>(iterators)...);
630  }
631 
632  template <size_t... Ns>
633  decltype(iterators) tup_inc(std::index_sequence<Ns...>) const {
634    return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
635  }
636 
637  template <size_t... Ns>
638  decltype(iterators) tup_dec(std::index_sequence<Ns...>) const {
639    return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
640  }
641 
642public:
643  zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
644 
645  value_type operator*() { return deref(std::index_sequence_for<Iters...>{}); }
646 
647  const value_type operator*() const {
648    return deref(std::index_sequence_for<Iters...>{});
649  }
650 
651  ZipType &operator++() {
652    iterators = tup_inc(std::index_sequence_for<Iters...>{});
653    return *reinterpret_cast<ZipType *>(this);
654  }
655 
656  ZipType &operator--() {
657    static_assert(Base::IsBidirectional,
658                  "All inner iterators must be at least bidirectional.");
659    iterators = tup_dec(std::index_sequence_for<Iters...>{});
660    return *reinterpret_cast<ZipType *>(this);
661  }
662};
663 
664template <typename... Iters>
665struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
666  using Base = zip_common<zip_first<Iters...>, Iters...>;
667 
668  bool operator==(const zip_first<Iters...> &other) const {
669    return std::get<0>(this->iterators) == std::get<0>(other.iterators);
670  }
671 
672  zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
673};
674 
675template <typename... Iters>
676class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
677  template <size_t... Ns>
678  bool test(const zip_shortest<Iters...> &other,
679            std::index_sequence<Ns...>) const {
680    return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
681                                              std::get<Ns>(other.iterators)...},
682                  identity<bool>{});
683  }
684 
685public:
686  using Base = zip_common<zip_shortest<Iters...>, Iters...>;
687 
688  zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
689 
690  bool operator==(const zip_shortest<Iters...> &other) const {
691    return !test(other, std::index_sequence_for<Iters...>{});
692  }
693};
694 
695template <template <typename...> class ItType, typename... Args> class zippy {
696public:
697  using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
698  using iterator_category = typename iterator::iterator_category;
699  using value_type = typename iterator::value_type;
700  using difference_type = typename iterator::difference_type;
701  using pointer = typename iterator::pointer;
702  using reference = typename iterator::reference;
703 
704private:
705  std::tuple<Args...> ts;
706 
707  template <size_t... Ns>
708  iterator begin_impl(std::index_sequence<Ns...>) const {
709    return iterator(std::begin(std::get<Ns>(ts))...);
710  }
711  template <size_t... Ns> iterator end_impl(std::index_sequence<Ns...>) const {
712    return iterator(std::end(std::get<Ns>(ts))...);
713  }
714 
715public:
716  zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
717 
718  iterator begin() const {
719    return begin_impl(std::index_sequence_for<Args...>{});
720  }
721  iterator end() const { return end_impl(std::index_sequence_for<Args...>{}); }
722};
723 
724} // end namespace detail
725 
726/// zip iterator for two or more iteratable types.
727template <typename T, typename U, typename... Args>
728detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
729                                                       Args &&... args) {
730  return detail::zippy<detail::zip_shortest, T, U, Args...>(
731      std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
732}
733 
734/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
735/// be the shortest.
736template <typename T, typename U, typename... Args>
737detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
738                                                          Args &&... args) {
739  return detail::zippy<detail::zip_first, T, U, Args...>(
740      std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
741}
742 
743namespace detail {
744template <typename Iter>
745Iter next_or_end(const Iter &I, const Iter &End) {
746  if (I == End)
747    return End;
748  return std::next(I);
749}
750 
751template <typename Iter>
752auto deref_or_none(const Iter &I, const Iter &End) -> llvm::Optional<
753    std::remove_const_t<std::remove_reference_t<decltype(*I)>>> {
754  if (I == End)
755    return None;
756  return *I;
757}
758 
759template <typename Iter> struct ZipLongestItemType {
760  using type =
761      llvm::Optional<typename std::remove_const<typename std::remove_reference<
762          decltype(*std::declval<Iter>())>::type>::type>;
763};
764 
765template <typename... Iters> struct ZipLongestTupleType {
766  using type = std::tuple<typename ZipLongestItemType<Iters>::type...>;
767};
768 
769template <typename... Iters>
770class zip_longest_iterator
771    : public iterator_facade_base<
772          zip_longest_iterator<Iters...>,
773          typename std::common_type<
774              std::forward_iterator_tag,
775              typename std::iterator_traits<Iters>::iterator_category...>::type,
776          typename ZipLongestTupleType<Iters...>::type,
777          typename std::iterator_traits<typename std::tuple_element<
778              0, std::tuple<Iters...>>::type>::difference_type,
779          typename ZipLongestTupleType<Iters...>::type *,
780          typename ZipLongestTupleType<Iters...>::type> {
781public:
782  using value_type = typename ZipLongestTupleType<Iters...>::type;
783 
784private:
785  std::tuple<Iters...> iterators;
786  std::tuple<Iters...> end_iterators;
787 
788  template <size_t... Ns>
789  bool test(const zip_longest_iterator<Iters...> &other,
790            std::index_sequence<Ns...>) const {
791    return llvm::any_of(
792        std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
793                                    std::get<Ns>(other.iterators)...},
794        identity<bool>{});
795  }
796 
797  template <size_t... Ns> value_type deref(std::index_sequence<Ns...>) const {
798    return value_type(
799        deref_or_none(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
800  }
801 
802  template <size_t... Ns>
803  decltype(iterators) tup_inc(std::index_sequence<Ns...>) const {
804    return std::tuple<Iters...>(
805        next_or_end(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
806  }
807 
808public:
809  zip_longest_iterator(std::pair<Iters &&, Iters &&>... ts)
810      : iterators(std::forward<Iters>(ts.first)...),
811        end_iterators(std::forward<Iters>(ts.second)...) {}
812 
813  value_type operator*() { return deref(std::index_sequence_for<Iters...>{}); }
814 
815  value_type operator*() const {
816    return deref(std::index_sequence_for<Iters...>{});
817  }
818 
819  zip_longest_iterator<Iters...> &operator++() {
820    iterators = tup_inc(std::index_sequence_for<Iters...>{});
821    return *this;
822  }
823 
824  bool operator==(const zip_longest_iterator<Iters...> &other) const {
825    return !test(other, std::index_sequence_for<Iters...>{});
826  }
827};
828 
829template <typename... Args> class zip_longest_range {
830public:
831  using iterator =
832      zip_longest_iterator<decltype(adl_begin(std::declval<Args>()))...>;
833  using iterator_category = typename iterator::iterator_category;
834  using value_type = typename iterator::value_type;
835  using difference_type = typename iterator::difference_type;
836  using pointer = typename iterator::pointer;
837  using reference = typename iterator::reference;
838 
839private:
840  std::tuple<Args...> ts;
841 
842  template <size_t... Ns>
843  iterator begin_impl(std::index_sequence<Ns...>) const {
844    return iterator(std::make_pair(adl_begin(std::get<Ns>(ts)),
845                                   adl_end(std::get<Ns>(ts)))...);
846  }
847 
848  template <size_t... Ns> iterator end_impl(std::index_sequence<Ns...>) const {
849    return iterator(std::make_pair(adl_end(std::get<Ns>(ts)),
850                                   adl_end(std::get<Ns>(ts)))...);
851  }
852 
853public:
854  zip_longest_range(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
855 
856  iterator begin() const {
857    return begin_impl(std::index_sequence_for<Args...>{});
858  }
859  iterator end() const { return end_impl(std::index_sequence_for<Args...>{}); }
860};
861} // namespace detail
862 
863/// Iterate over two or more iterators at the same time. Iteration continues
864/// until all iterators reach the end. The llvm::Optional only contains a value
865/// if the iterator has not reached the end.
866template <typename T, typename U, typename... Args>
867detail::zip_longest_range<T, U, Args...> zip_longest(T &&t, U &&u,
868                                                     Args &&... args) {
869  return detail::zip_longest_range<T, U, Args...>(
870      std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
871}
872 
873/// Iterator wrapper that concatenates sequences together.
874///
875/// This can concatenate different iterators, even with different types, into
876/// a single iterator provided the value types of all the concatenated
877/// iterators expose `reference` and `pointer` types that can be converted to
878/// `ValueT &` and `ValueT *` respectively. It doesn't support more
879/// interesting/customized pointer or reference types.
880///
881/// Currently this only supports forward or higher iterator categories as
882/// inputs and always exposes a forward iterator interface.
883template <typename ValueT, typename... IterTs>
884class concat_iterator
885    : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
886                                  std::forward_iterator_tag, ValueT> {
887  using BaseT = typename concat_iterator::iterator_facade_base;
888 
889  /// We store both the current and end iterators for each concatenated
890  /// sequence in a tuple of pairs.
891  ///
892  /// Note that something like iterator_range seems nice at first here, but the
893  /// range properties are of little benefit and end up getting in the way
894  /// because we need to do mutation on the current iterators.
895  std::tuple<IterTs...> Begins;
896  std::tuple<IterTs...> Ends;
897 
898  /// Attempts to increment a specific iterator.
899  ///
900  /// Returns true if it was able to increment the iterator. Returns false if
901  /// the iterator is already at the end iterator.
902  template <size_t Index> bool incrementHelper() {
903    auto &Begin = std::get<Index>(Begins);
904    auto &End = std::get<Index>(Ends);
905    if (Begin == End)
906      return false;
907 
908    ++Begin;
909    return true;
910  }
911 
912  /// Increments the first non-end iterator.
913  ///
914  /// It is an error to call this with all iterators at the end.
915  template <size_t... Ns> void increment(std::index_sequence<Ns...>) {
916    // Build a sequence of functions to increment each iterator if possible.
917    bool (concat_iterator::*IncrementHelperFns[])() = {
918        &concat_iterator::incrementHelper<Ns>...};
919 
920    // Loop over them, and stop as soon as we succeed at incrementing one.
921    for (auto &IncrementHelperFn : IncrementHelperFns)
922      if ((this->*IncrementHelperFn)())
923        return;
924 
925    llvm_unreachable("Attempted to increment an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to increment an end concat iterator!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 925);
926  }
927 
928  /// Returns null if the specified iterator is at the end. Otherwise,
929  /// dereferences the iterator and returns the address of the resulting
930  /// reference.
931  template <size_t Index> ValueT *getHelper() const {
932    auto &Begin = std::get<Index>(Begins);
933    auto &End = std::get<Index>(Ends);
934    if (Begin == End)
935      return nullptr;
936 
937    return &*Begin;
938  }
939 
940  /// Finds the first non-end iterator, dereferences, and returns the resulting
941  /// reference.
942  ///
943  /// It is an error to call this with all iterators at the end.
944  template <size_t... Ns> ValueT &get(std::index_sequence<Ns...>) const {
945    // Build a sequence of functions to get from iterator if possible.
946    ValueT *(concat_iterator::*GetHelperFns[])() const = {
947        &concat_iterator::getHelper<Ns>...};
948 
949    // Loop over them, and return the first result we find.
950    for (auto &GetHelperFn : GetHelperFns)
951      if (ValueT *P = (this->*GetHelperFn)())
952        return *P;
953 
954    llvm_unreachable("Attempted to get a pointer from an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to get a pointer from an end concat iterator!"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 954);
955  }
956 
957public:
958  /// Constructs an iterator from a sequence of ranges.
959  ///
960  /// We need the full range to know how to switch between each of the
961  /// iterators.
962  template <typename... RangeTs>
963  explicit concat_iterator(RangeTs &&... Ranges)
964      : Begins(std::begin(Ranges)...), Ends(std::end(Ranges)...) {}
965 
966  using BaseT::operator++;
967 
968  concat_iterator &operator++() {
969    increment(std::index_sequence_for<IterTs...>());
970    return *this;
971  }
972 
973  ValueT &operator*() const {
974    return get(std::index_sequence_for<IterTs...>());
975  }
976 
977  bool operator==(const concat_iterator &RHS) const {
978    return Begins == RHS.Begins && Ends == RHS.Ends;
979  }
980};
981 
982namespace detail {
983 
984/// Helper to store a sequence of ranges being concatenated and access them.
985///
986/// This is designed to facilitate providing actual storage when temporaries
987/// are passed into the constructor such that we can use it as part of range
988/// based for loops.
989template <typename ValueT, typename... RangeTs> class concat_range {
990public:
991  using iterator =
992      concat_iterator<ValueT,
993                      decltype(std::begin(std::declval<RangeTs &>()))...>;
994 
995private:
996  std::tuple<RangeTs...> Ranges;
997 
998  template <size_t... Ns> iterator begin_impl(std::index_sequence<Ns...>) {
999    return iterator(std::get<Ns>(Ranges)...);
1000  }
1001  template <size_t... Ns> iterator end_impl(std::index_sequence<Ns...>) {
1002    return iterator(make_range(std::end(std::get<Ns>(Ranges)),
1003                               std::end(std::get<Ns>(Ranges)))...);
1004  }
1005 
1006public:
1007  concat_range(RangeTs &&... Ranges)
1008      : Ranges(std::forward<RangeTs>(Ranges)...) {}
1009 
1010  iterator begin() { return begin_impl(std::index_sequence_for<RangeTs...>{}); }
1011  iterator end() { return end_impl(std::index_sequence_for<RangeTs...>{}); }
1012};
1013 
1014} // end namespace detail
1015 
1016/// Concatenated range across two or more ranges.
1017///
1018/// The desired value type must be explicitly specified.
1019template <typename ValueT, typename... RangeTs>
1020detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
1021  static_assert(sizeof...(RangeTs) > 1,
1022                "Need more than one range to concatenate!");
1023  return detail::concat_range<ValueT, RangeTs...>(
1024      std::forward<RangeTs>(Ranges)...);
1025}
1026 
1027/// A utility class used to implement an iterator that contains some base object
1028/// and an index. The iterator moves the index but keeps the base constant.
1029template <typename DerivedT, typename BaseT, typename T,
1030          typename PointerT = T *, typename ReferenceT = T &>
1031class indexed_accessor_iterator
1032    : public llvm::iterator_facade_base<DerivedT,
1033                                        std::random_access_iterator_tag, T,
1034                                        std::ptrdiff_t, PointerT, ReferenceT> {
1035public:
1036  ptrdiff_t operator-(const indexed_accessor_iterator &rhs) const {
1037    assert(base == rhs.base && "incompatible iterators")((base == rhs.base && "incompatible iterators") ? static_cast
<void> (0) : __assert_fail ("base == rhs.base && \"incompatible iterators\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1037, __PRETTY_FUNCTION__));
1038    return index - rhs.index;
1039  }
1040  bool operator==(const indexed_accessor_iterator &rhs) const {
1041    return base == rhs.base && index == rhs.index;
1042  }
1043  bool operator<(const indexed_accessor_iterator &rhs) const {
1044    assert(base == rhs.base && "incompatible iterators")((base == rhs.base && "incompatible iterators") ? static_cast
<void> (0) : __assert_fail ("base == rhs.base && \"incompatible iterators\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1044, __PRETTY_FUNCTION__));
1045    return index < rhs.index;
1046  }
1047 
1048  DerivedT &operator+=(ptrdiff_t offset) {
1049    this->index += offset;
1050    return static_cast<DerivedT &>(*this);
1051  }
1052  DerivedT &operator-=(ptrdiff_t offset) {
1053    this->index -= offset;
1054    return static_cast<DerivedT &>(*this);
1055  }
1056 
1057  /// Returns the current index of the iterator.
1058  ptrdiff_t getIndex() const { return index; }
1059 
1060  /// Returns the current base of the iterator.
1061  const BaseT &getBase() const { return base; }
1062 
1063protected:
1064  indexed_accessor_iterator(BaseT base, ptrdiff_t index)
1065      : base(base), index(index) {}
1066  BaseT base;
1067  ptrdiff_t index;
1068};
1069 
1070namespace detail {
1071/// The class represents the base of a range of indexed_accessor_iterators. It
1072/// provides support for many different range functionalities, e.g.
1073/// drop_front/slice/etc.. Derived range classes must implement the following
1074/// static methods:
1075///   * ReferenceT dereference_iterator(const BaseT &base, ptrdiff_t index)
1076///     - Dereference an iterator pointing to the base object at the given
1077///       index.
1078///   * BaseT offset_base(const BaseT &base, ptrdiff_t index)
1079///     - Return a new base that is offset from the provide base by 'index'
1080///       elements.
1081template <typename DerivedT, typename BaseT, typename T,
1082          typename PointerT = T *, typename ReferenceT = T &>
1083class indexed_accessor_range_base {
1084public:
1085  using RangeBaseT =
1086      indexed_accessor_range_base<DerivedT, BaseT, T, PointerT, ReferenceT>;
1087 
1088  /// An iterator element of this range.
1089  class iterator : public indexed_accessor_iterator<iterator, BaseT, T,
1090                                                    PointerT, ReferenceT> {
1091  public:
1092    // Index into this iterator, invoking a static method on the derived type.
1093    ReferenceT operator*() const {
1094      return DerivedT::dereference_iterator(this->getBase(), this->getIndex());
1095    }
1096 
1097  private:
1098    iterator(BaseT owner, ptrdiff_t curIndex)
1099        : indexed_accessor_iterator<iterator, BaseT, T, PointerT, ReferenceT>(
1100              owner, curIndex) {}
1101 
1102    /// Allow access to the constructor.
1103    friend indexed_accessor_range_base<DerivedT, BaseT, T, PointerT,
1104                                       ReferenceT>;
1105  };
1106 
1107  indexed_accessor_range_base(iterator begin, iterator end)
1108      : base(offset_base(begin.getBase(), begin.getIndex())),
1109        count(end.getIndex() - begin.getIndex()) {}
1110  indexed_accessor_range_base(const iterator_range<iterator> &range)
1111      : indexed_accessor_range_base(range.begin(), range.end()) {}
1112  indexed_accessor_range_base(BaseT base, ptrdiff_t count)
1113      : base(base), count(count) {}
1114 
1115  iterator begin() const { return iterator(base, 0); }
1116  iterator end() const { return iterator(base, count); }
1117  ReferenceT operator[](unsigned index) const {
1118    assert(index < size() && "invalid index for value range")((index < size() && "invalid index for value range"
) ? static_cast<void> (0) : __assert_fail ("index < size() && \"invalid index for value range\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1118, __PRETTY_FUNCTION__));
1119    return DerivedT::dereference_iterator(base, index);
1120  }
1121  ReferenceT front() const {
1122    assert(!empty() && "expected non-empty range")((!empty() && "expected non-empty range") ? static_cast
<void> (0) : __assert_fail ("!empty() && \"expected non-empty range\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1122, __PRETTY_FUNCTION__));
1123    return (*this)[0];
1124  }
1125  ReferenceT back() const {
1126    assert(!empty() && "expected non-empty range")((!empty() && "expected non-empty range") ? static_cast
<void> (0) : __assert_fail ("!empty() && \"expected non-empty range\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1126, __PRETTY_FUNCTION__));
1127    return (*this)[size() - 1];
1128  }
1129 
1130  /// Compare this range with another.
1131  template <typename OtherT> bool operator==(const OtherT &other) const {
1132    return size() ==
1133               static_cast<size_t>(std::distance(other.begin(), other.end())) &&
1134           std::equal(begin(), end(), other.begin());
1135  }
1136  template <typename OtherT> bool operator!=(const OtherT &other) const {
1137    return !(*this == other);
1138  }
1139 
1140  /// Return the size of this range.
1141  size_t size() const { return count; }
1142 
1143  /// Return if the range is empty.
1144  bool empty() const { return size() == 0; }
1145 
1146  /// Drop the first N elements, and keep M elements.
1147  DerivedT slice(size_t n, size_t m) const {
1148    assert(n + m <= size() && "invalid size specifiers")((n + m <= size() && "invalid size specifiers") ? static_cast
<void> (0) : __assert_fail ("n + m <= size() && \"invalid size specifiers\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1148, __PRETTY_FUNCTION__));
1149    return DerivedT(offset_base(base, n), m);
1150  }
1151 
1152  /// Drop the first n elements.
1153  DerivedT drop_front(size_t n = 1) const {
1154    assert(size() >= n && "Dropping more elements than exist")((size() >= n && "Dropping more elements than exist"
) ? static_cast<void> (0) : __assert_fail ("size() >= n && \"Dropping more elements than exist\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1154, __PRETTY_FUNCTION__));
1155    return slice(n, size() - n);
1156  }
1157  /// Drop the last n elements.
1158  DerivedT drop_back(size_t n = 1) const {
1159    assert(size() >= n && "Dropping more elements than exist")((size() >= n && "Dropping more elements than exist"
) ? static_cast<void> (0) : __assert_fail ("size() >= n && \"Dropping more elements than exist\""
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1159, __PRETTY_FUNCTION__));
1160    return DerivedT(base, size() - n);
1161  }
1162 
1163  /// Take the first n elements.
1164  DerivedT take_front(size_t n = 1) const {
1165    return n < size() ? drop_back(size() - n)
1166                      : static_cast<const DerivedT &>(*this);
1167  }
1168 
1169  /// Take the last n elements.
1170  DerivedT take_back(size_t n = 1) const {
1171    return n < size() ? drop_front(size() - n)
1172                      : static_cast<const DerivedT &>(*this);
1173  }
1174 
1175  /// Allow conversion to any type accepting an iterator_range.
1176  template <typename RangeT, typename = std::enable_if_t<std::is_constructible<
1177                                 RangeT, iterator_range<iterator>>::value>>
1178  operator RangeT() const {
1179    return RangeT(iterator_range<iterator>(*this));
1180  }
1181 
1182  /// Returns the base of this range.
1183  const BaseT &getBase() const { return base; }
1184 
1185private:
1186  /// Offset the given base by the given amount.
1187  static BaseT offset_base(const BaseT &base, size_t n) {
1188    return n == 0 ? base : DerivedT::offset_base(base, n);
1189  }
1190 
1191protected:
1192  indexed_accessor_range_base(const indexed_accessor_range_base &) = default;
1193  indexed_accessor_range_base(indexed_accessor_range_base &&) = default;
1194  indexed_accessor_range_base &
1195  operator=(const indexed_accessor_range_base &) = default;
1196 
1197  /// The base that owns the provided range of values.
1198  BaseT base;
1199  /// The size from the owning range.
1200  ptrdiff_t count;
1201};
1202} // end namespace detail
1203 
1204/// This class provides an implementation of a range of
1205/// indexed_accessor_iterators where the base is not indexable. Ranges with
1206/// bases that are offsetable should derive from indexed_accessor_range_base
1207/// instead. Derived range classes are expected to implement the following
1208/// static method:
1209///   * ReferenceT dereference(const BaseT &base, ptrdiff_t index)
1210///     - Dereference an iterator pointing to a parent base at the given index.
1211template <typename DerivedT, typename BaseT, typename T,
1212          typename PointerT = T *, typename ReferenceT = T &>
1213class indexed_accessor_range
1214    : public detail::indexed_accessor_range_base<
1215          DerivedT, std::pair<BaseT, ptrdiff_t>, T, PointerT, ReferenceT> {
1216public:
1217  indexed_accessor_range(BaseT base, ptrdiff_t startIndex, ptrdiff_t count)
1218      : detail::indexed_accessor_range_base<
1219            DerivedT, std::pair<BaseT, ptrdiff_t>, T, PointerT, ReferenceT>(
1220            std::make_pair(base, startIndex), count) {}
1221  using detail::indexed_accessor_range_base<
1222      DerivedT, std::pair<BaseT, ptrdiff_t>, T, PointerT,
1223      ReferenceT>::indexed_accessor_range_base;
1224 
1225  /// Returns the current base of the range.
1226  const BaseT &getBase() const { return this->base.first; }
1227 
1228  /// Returns the current start index of the range.
1229  ptrdiff_t getStartIndex() const { return this->base.second; }
1230 
1231  /// See `detail::indexed_accessor_range_base` for details.
1232  static std::pair<BaseT, ptrdiff_t>
1233  offset_base(const std::pair<BaseT, ptrdiff_t> &base, ptrdiff_t index) {
1234    // We encode the internal base as a pair of the derived base and a start
1235    // index into the derived base.
1236    return std::make_pair(base.first, base.second + index);
1237  }
1238  /// See `detail::indexed_accessor_range_base` for details.
1239  static ReferenceT
1240  dereference_iterator(const std::pair<BaseT, ptrdiff_t> &base,
1241                       ptrdiff_t index) {
1242    return DerivedT::dereference(base.first, base.second + index);
1243  }
1244};
1245 
1246/// Given a container of pairs, return a range over the first elements.
1247template <typename ContainerTy> auto make_first_range(ContainerTy &&c) {
1248  return llvm::map_range(
1249      std::forward<ContainerTy>(c),
1250      [](decltype((*std::begin(c))) elt) -> decltype((elt.first)) {
1251        return elt.first;
1252      });
1253}
1254 
1255/// Given a container of pairs, return a range over the second elements.
1256template <typename ContainerTy> auto make_second_range(ContainerTy &&c) {
1257  return llvm::map_range(
1258      std::forward<ContainerTy>(c),
1259      [](decltype((*std::begin(c))) elt) -> decltype((elt.second)) {
1260        return elt.second;
1261      });
1262}
1263 
1264//===----------------------------------------------------------------------===//
1265//     Extra additions to <utility>
1266//===----------------------------------------------------------------------===//
1267 
1268/// Function object to check whether the first component of a std::pair
1269/// compares less than the first component of another std::pair.
1270struct less_first {
1271  template <typename T> bool operator()(const T &lhs, const T &rhs) const {
1272    return lhs.first < rhs.first;
1273  }
1274};
1275 
1276/// Function object to check whether the second component of a std::pair
1277/// compares less than the second component of another std::pair.
1278struct less_second {
1279  template <typename T> bool operator()(const T &lhs, const T &rhs) const {
1280    return lhs.second < rhs.second;
1281  }
1282};
1283 
1284/// \brief Function object to apply a binary function to the first component of
1285/// a std::pair.
1286template<typename FuncTy>
1287struct on_first {
1288  FuncTy func;
1289 
1290  template <typename T>
1291  decltype(auto) operator()(const T &lhs, const T &rhs) const {
1292    return func(lhs.first, rhs.first);
1293  }
1294};
1295 
1296/// Utility type to build an inheritance chain that makes it easy to rank
1297/// overload candidates.
1298template <int N> struct rank : rank<N - 1> {};
1299template <> struct rank<0> {};
1300 
1301/// traits class for checking whether type T is one of any of the given
1302/// types in the variadic list.
1303template <typename T, typename... Ts> struct is_one_of {
1304  static const bool value = false;
1305};
1306 
1307template <typename T, typename U, typename... Ts>
1308struct is_one_of<T, U, Ts...> {
1309  static const bool value =
1310      std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
1311};
1312 
1313/// traits class for checking whether type T is a base class for all
1314///  the given types in the variadic list.
1315template <typename T, typename... Ts> struct are_base_of {
1316  static const bool value = true;
1317};
1318 
1319template <typename T, typename U, typename... Ts>
1320struct are_base_of<T, U, Ts...> {
1321  static const bool value =
1322      std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
1323};
1324 
1325//===----------------------------------------------------------------------===//
1326//     Extra additions for arrays
1327//===----------------------------------------------------------------------===//
1328 
1329// We have a copy here so that LLVM behaves the same when using different
1330// standard libraries.
1331template <class Iterator, class RNG>
1332void shuffle(Iterator first, Iterator last, RNG &&g) {
1333  // It would be better to use a std::uniform_int_distribution,
1334  // but that would be stdlib dependent.
1335  for (auto size = last - first; size > 1; ++first, (void)--size)
1336    std::iter_swap(first, first + g() % size);
1337}
1338 
1339/// Find the length of an array.
1340template <class T, std::size_t N>
1341constexpr inline size_t array_lengthof(T (&)[N]) {
1342  return N;
1343}
1344 
1345/// Adapt std::less<T> for array_pod_sort.
1346template<typename T>
1347inline int array_pod_sort_comparator(const void *P1, const void *P2) {
1348  if (std::less<T>()(*reinterpret_cast<const T*>(P1),
1349                     *reinterpret_cast<const T*>(P2)))
1350    return -1;
1351  if (std::less<T>()(*reinterpret_cast<const T*>(P2),
1352                     *reinterpret_cast<const T*>(P1)))
1353    return 1;
1354  return 0;
1355}
1356 
1357/// get_array_pod_sort_comparator - This is an internal helper function used to
1358/// get type deduction of T right.
1359template<typename T>
1360inline int (*get_array_pod_sort_comparator(const T &))
1361             (const void*, const void*) {
1362  return array_pod_sort_comparator<T>;
1363}
1364 
1365#ifdef EXPENSIVE_CHECKS
1366namespace detail {
1367 
1368inline unsigned presortShuffleEntropy() {
1369  static unsigned Result(std::random_device{}());
1370  return Result;
1371}
1372 
1373template <class IteratorTy>
1374inline void presortShuffle(IteratorTy Start, IteratorTy End) {
1375  std::mt19937 Generator(presortShuffleEntropy());
1376  std::shuffle(Start, End, Generator);
1377}
1378 
1379} // end namespace detail
1380#endif
1381 
1382/// array_pod_sort - This sorts an array with the specified start and end
1383/// extent.  This is just like std::sort, except that it calls qsort instead of
1384/// using an inlined template.  qsort is slightly slower than std::sort, but
1385/// most sorts are not performance critical in LLVM and std::sort has to be
1386/// template instantiated for each type, leading to significant measured code
1387/// bloat.  This function should generally be used instead of std::sort where
1388/// possible.
1389///
1390/// This function assumes that you have simple POD-like types that can be
1391/// compared with std::less and can be moved with memcpy.  If this isn't true,
1392/// you should use std::sort.
1393///
1394/// NOTE: If qsort_r were portable, we could allow a custom comparator and
1395/// default to std::less.
1396template<class IteratorTy>
1397inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
1398  // Don't inefficiently call qsort with one element or trigger undefined
1399  // behavior with an empty sequence.
1400  auto NElts = End - Start;
1401  if (NElts <= 1) return;
1402#ifdef EXPENSIVE_CHECKS
1403  detail::presortShuffle<IteratorTy>(Start, End);
1404#endif
1405  qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
1406}
1407 
1408template <class IteratorTy>
1409inline void array_pod_sort(
1410    IteratorTy Start, IteratorTy End,
1411    int (*Compare)(
1412        const typename std::iterator_traits<IteratorTy>::value_type *,
1413        const typename std::iterator_traits<IteratorTy>::value_type *)) {
1414  // Don't inefficiently call qsort with one element or trigger undefined
1415  // behavior with an empty sequence.
1416  auto NElts = End - Start;
1417  if (NElts <= 1) return;
1418#ifdef EXPENSIVE_CHECKS
1419  detail::presortShuffle<IteratorTy>(Start, End);
1420#endif
1421  qsort(&*Start, NElts, sizeof(*Start),
1422        reinterpret_cast<int (*)(const void *, const void *)>(Compare));
1423}
1424 
1425namespace detail {
1426template <typename T>
1427// We can use qsort if the iterator type is a pointer and the underlying value
1428// is trivially copyable.
1429using sort_trivially_copyable = conjunction<
1430    std::is_pointer<T>,
1431    std::is_trivially_copyable<typename std::iterator_traits<T>::value_type>>;
1432} // namespace detail
1433 
1434// Provide wrappers to std::sort which shuffle the elements before sorting
1435// to help uncover non-deterministic behavior (PR35135).
1436template <typename IteratorTy,
1437          std::enable_if_t<!detail::sort_trivially_copyable<IteratorTy>::value,
1438                           int> = 0>
1439inline void sort(IteratorTy Start, IteratorTy End) {
1440#ifdef EXPENSIVE_CHECKS
1441  detail::presortShuffle<IteratorTy>(Start, End);
1442#endif
1443  std::sort(Start, End);
1444}
1445 
1446// Forward trivially copyable types to array_pod_sort. This avoids a large
1447// amount of code bloat for a minor performance hit.
1448template <typename IteratorTy,
1449          std::enable_if_t<detail::sort_trivially_copyable<IteratorTy>::value,
1450                           int> = 0>
1451inline void sort(IteratorTy Start, IteratorTy End) {
1452  array_pod_sort(Start, End);
1453}
1454 
1455template <typename Container> inline void sort(Container &&C) {
1456  llvm::sort(adl_begin(C), adl_end(C));
1457}
1458 
1459template <typename IteratorTy, typename Compare>
1460inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
1461#ifdef EXPENSIVE_CHECKS
1462  detail::presortShuffle<IteratorTy>(Start, End);
1463#endif
1464  std::sort(Start, End, Comp);
1465}
1466 
1467template <typename Container, typename Compare>
1468inline void sort(Container &&C, Compare Comp) {
1469  llvm::sort(adl_begin(C), adl_end(C), Comp);
1470}
1471 
1472//===----------------------------------------------------------------------===//
1473//     Extra additions to <algorithm>
1474//===----------------------------------------------------------------------===//
1475 
1476/// Get the size of a range. This is a wrapper function around std::distance
1477/// which is only enabled when the operation is O(1).
1478template <typename R>
1479auto size(R &&Range,
1480          std::enable_if_t<
1481              std::is_base_of<std::random_access_iterator_tag,
1482                              typename std::iterator_traits<decltype(
1483                                  Range.begin())>::iterator_category>::value,
1484              void> * = nullptr) {
1485  return std::distance(Range.begin(), Range.end());
1486}
1487 
1488/// Provide wrappers to std::for_each which take ranges instead of having to
1489/// pass begin/end explicitly.
1490template <typename R, typename UnaryFunction>
1491UnaryFunction for_each(R &&Range, UnaryFunction F) {
1492  return std::for_each(adl_begin(Range), adl_end(Range), F);
1493}
1494 
1495/// Provide wrappers to std::all_of which take ranges instead of having to pass
1496/// begin/end explicitly.
1497template <typename R, typename UnaryPredicate>
1498bool all_of(R &&Range, UnaryPredicate P) {
1499  return std::all_of(adl_begin(Range), adl_end(Range), P);
1500}
1501 
1502/// Provide wrappers to std::any_of which take ranges instead of having to pass
1503/// begin/end explicitly.
1504template <typename R, typename UnaryPredicate>
1505bool any_of(R &&Range, UnaryPredicate P) {
1506  return std::any_of(adl_begin(Range), adl_end(Range), P);
22
←
Calling 'any_of<llvm::ilist_iterator<llvm::ilist_detail::node_options<llvm::Instruction, true, false, void>, false, false>, (lambda at /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp:2915:19)>'→
30
←
Returning from 'any_of<llvm::ilist_iterator<llvm::ilist_detail::node_options<llvm::Instruction, true, false, void>, false, false>, (lambda at /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp:2915:19)>'→
31
←
Returning zero, which participates in a condition later→
1507}
1508 
1509/// Provide wrappers to std::none_of which take ranges instead of having to pass
1510/// begin/end explicitly.
1511template <typename R, typename UnaryPredicate>
1512bool none_of(R &&Range, UnaryPredicate P) {
1513  return std::none_of(adl_begin(Range), adl_end(Range), P);
1514}
1515 
1516/// Provide wrappers to std::find which take ranges instead of having to pass
1517/// begin/end explicitly.
1518template <typename R, typename T> auto find(R &&Range, const T &Val) {
1519  return std::find(adl_begin(Range), adl_end(Range), Val);
1520}
1521 
1522/// Provide wrappers to std::find_if which take ranges instead of having to pass
1523/// begin/end explicitly.
1524template <typename R, typename UnaryPredicate>
1525auto find_if(R &&Range, UnaryPredicate P) {
1526  return std::find_if(adl_begin(Range), adl_end(Range), P);
1527}
1528 
1529template <typename R, typename UnaryPredicate>
1530auto find_if_not(R &&Range, UnaryPredicate P) {
1531  return std::find_if_not(adl_begin(Range), adl_end(Range), P);
1532}
1533 
1534/// Provide wrappers to std::remove_if which take ranges instead of having to
1535/// pass begin/end explicitly.
1536template <typename R, typename UnaryPredicate>
1537auto remove_if(R &&Range, UnaryPredicate P) {
1538  return std::remove_if(adl_begin(Range), adl_end(Range), P);
1539}
1540 
1541/// Provide wrappers to std::copy_if which take ranges instead of having to
1542/// pass begin/end explicitly.
1543template <typename R, typename OutputIt, typename UnaryPredicate>
1544OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
1545  return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
1546}
1547 
1548template <typename R, typename OutputIt>
1549OutputIt copy(R &&Range, OutputIt Out) {
1550  return std::copy(adl_begin(Range), adl_end(Range), Out);
1551}
1552 
1553/// Provide wrappers to std::move which take ranges instead of having to
1554/// pass begin/end explicitly.
1555template <typename R, typename OutputIt>
1556OutputIt move(R &&Range, OutputIt Out) {
1557  return std::move(adl_begin(Range), adl_end(Range), Out);
1558}
1559 
1560/// Wrapper function around std::find to detect if an element exists
1561/// in a container.
1562template <typename R, typename E>
1563bool is_contained(R &&Range, const E &Element) {
1564  return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
1565}
1566 
1567/// Wrapper function around std::is_sorted to check if elements in a range \p R
1568/// are sorted with respect to a comparator \p C.
1569template <typename R, typename Compare> bool is_sorted(R &&Range, Compare C) {
1570  return std::is_sorted(adl_begin(Range), adl_end(Range), C);
1571}
1572 
1573/// Wrapper function around std::is_sorted to check if elements in a range \p R
1574/// are sorted in non-descending order.
1575template <typename R> bool is_sorted(R &&Range) {
1576  return std::is_sorted(adl_begin(Range), adl_end(Range));
1577}
1578 
1579/// Wrapper function around std::count to count the number of times an element
1580/// \p Element occurs in the given range \p Range.
1581template <typename R, typename E> auto count(R &&Range, const E &Element) {
1582  return std::count(adl_begin(Range), adl_end(Range), Element);
1583}
1584 
1585/// Wrapper function around std::count_if to count the number of times an
1586/// element satisfying a given predicate occurs in a range.
1587template <typename R, typename UnaryPredicate>
1588auto count_if(R &&Range, UnaryPredicate P) {
1589  return std::count_if(adl_begin(Range), adl_end(Range), P);
1590}
1591 
1592/// Wrapper function around std::transform to apply a function to a range and
1593/// store the result elsewhere.
1594template <typename R, typename OutputIt, typename UnaryFunction>
1595OutputIt transform(R &&Range, OutputIt d_first, UnaryFunction F) {
1596  return std::transform(adl_begin(Range), adl_end(Range), d_first, F);
1597}
1598 
1599/// Provide wrappers to std::partition which take ranges instead of having to
1600/// pass begin/end explicitly.
1601template <typename R, typename UnaryPredicate>
1602auto partition(R &&Range, UnaryPredicate P) {
1603  return std::partition(adl_begin(Range), adl_end(Range), P);
1604}
1605 
1606/// Provide wrappers to std::lower_bound which take ranges instead of having to
1607/// pass begin/end explicitly.
1608template <typename R, typename T> auto lower_bound(R &&Range, T &&Value) {
1609  return std::lower_bound(adl_begin(Range), adl_end(Range),
1610                          std::forward<T>(Value));
1611}
1612 
1613template <typename R, typename T, typename Compare>
1614auto lower_bound(R &&Range, T &&Value, Compare C) {
1615  return std::lower_bound(adl_begin(Range), adl_end(Range),
1616                          std::forward<T>(Value), C);
1617}
1618 
1619/// Provide wrappers to std::upper_bound which take ranges instead of having to
1620/// pass begin/end explicitly.
1621template <typename R, typename T> auto upper_bound(R &&Range, T &&Value) {
1622  return std::upper_bound(adl_begin(Range), adl_end(Range),
1623                          std::forward<T>(Value));
1624}
1625 
1626template <typename R, typename T, typename Compare>
1627auto upper_bound(R &&Range, T &&Value, Compare C) {
1628  return std::upper_bound(adl_begin(Range), adl_end(Range),
1629                          std::forward<T>(Value), C);
1630}
1631 
1632template <typename R>
1633void stable_sort(R &&Range) {
1634  std::stable_sort(adl_begin(Range), adl_end(Range));
1635}
1636 
1637template <typename R, typename Compare>
1638void stable_sort(R &&Range, Compare C) {
1639  std::stable_sort(adl_begin(Range), adl_end(Range), C);
1640}
1641 
1642/// Binary search for the first iterator in a range where a predicate is false.
1643/// Requires that C is always true below some limit, and always false above it.
1644template <typename R, typename Predicate,
1645          typename Val = decltype(*adl_begin(std::declval<R>()))>
1646auto partition_point(R &&Range, Predicate P) {
1647  return std::partition_point(adl_begin(Range), adl_end(Range), P);
1648}
1649 
1650/// Wrapper function around std::equal to detect if all elements
1651/// in a container are same.
1652template <typename R>
1653bool is_splat(R &&Range) {
1654  size_t range_size = size(Range);
1655  return range_size != 0 && (range_size == 1 ||
1656         std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
1657}
1658 
1659/// Provide a container algorithm similar to C++ Library Fundamentals v2's
1660/// `erase_if` which is equivalent to:
1661///
1662///   C.erase(remove_if(C, pred), C.end());
1663///
1664/// This version works for any container with an erase method call accepting
1665/// two iterators.
1666template <typename Container, typename UnaryPredicate>
1667void erase_if(Container &C, UnaryPredicate P) {
1668  C.erase(remove_if(C, P), C.end());
1669}
1670 
1671/// Wrapper function to remove a value from a container:
1672///
1673/// C.erase(remove(C.begin(), C.end(), V), C.end());
1674template <typename Container, typename ValueType>
1675void erase_value(Container &C, ValueType V) {
1676  C.erase(std::remove(C.begin(), C.end(), V), C.end());
1677}
1678 
1679/// Wrapper function to append a range to a container.
1680///
1681/// C.insert(C.end(), R.begin(), R.end());
1682template <typename Container, typename Range>
1683inline void append_range(Container &C, Range &&R) {
1684  C.insert(C.end(), R.begin(), R.end());
1685}
1686 
1687/// Given a sequence container Cont, replace the range [ContIt, ContEnd) with
1688/// the range [ValIt, ValEnd) (which is not from the same container).
1689template<typename Container, typename RandomAccessIterator>
1690void replace(Container &Cont, typename Container::iterator ContIt,
1691             typename Container::iterator ContEnd, RandomAccessIterator ValIt,
1692             RandomAccessIterator ValEnd) {
1693  while (true) {
1694    if (ValIt == ValEnd) {
1695      Cont.erase(ContIt, ContEnd);
1696      return;
1697    } else if (ContIt == ContEnd) {
1698      Cont.insert(ContIt, ValIt, ValEnd);
1699      return;
1700    }
1701    *ContIt++ = *ValIt++;
1702  }
1703}
1704 
1705/// Given a sequence container Cont, replace the range [ContIt, ContEnd) with
1706/// the range R.
1707template<typename Container, typename Range = std::initializer_list<
1708                                 typename Container::value_type>>
1709void replace(Container &Cont, typename Container::iterator ContIt,
1710             typename Container::iterator ContEnd, Range R) {
1711  replace(Cont, ContIt, ContEnd, R.begin(), R.end());
1712}
1713 
1714/// An STL-style algorithm similar to std::for_each that applies a second
1715/// functor between every pair of elements.
1716///
1717/// This provides the control flow logic to, for example, print a
1718/// comma-separated list:
1719/// \code
1720///   interleave(names.begin(), names.end(),
1721///              [&](StringRef name) { os << name; },
1722///              [&] { os << ", "; });
1723/// \endcode
1724template <typename ForwardIterator, typename UnaryFunctor,
1725          typename NullaryFunctor,
1726          typename = typename std::enable_if<
1727              !std::is_constructible<StringRef, UnaryFunctor>::value &&
1728              !std::is_constructible<StringRef, NullaryFunctor>::value>::type>
1729inline void interleave(ForwardIterator begin, ForwardIterator end,
1730                       UnaryFunctor each_fn, NullaryFunctor between_fn) {
1731  if (begin == end)
1732    return;
1733  each_fn(*begin);
1734  ++begin;
1735  for (; begin != end; ++begin) {
1736    between_fn();
1737    each_fn(*begin);
1738  }
1739}
1740 
1741template <typename Container, typename UnaryFunctor, typename NullaryFunctor,
1742          typename = typename std::enable_if<
1743              !std::is_constructible<StringRef, UnaryFunctor>::value &&
1744              !std::is_constructible<StringRef, NullaryFunctor>::value>::type>
1745inline void interleave(const Container &c, UnaryFunctor each_fn,
1746                       NullaryFunctor between_fn) {
1747  interleave(c.begin(), c.end(), each_fn, between_fn);
1748}
1749 
1750/// Overload of interleave for the common case of string separator.
1751template <typename Container, typename UnaryFunctor, typename StreamT,
1752          typename T = detail::ValueOfRange<Container>>
1753inline void interleave(const Container &c, StreamT &os, UnaryFunctor each_fn,
1754                       const StringRef &separator) {
1755  interleave(c.begin(), c.end(), each_fn, [&] { os << separator; });
1756}
1757template <typename Container, typename StreamT,
1758          typename T = detail::ValueOfRange<Container>>
1759inline void interleave(const Container &c, StreamT &os,
1760                       const StringRef &separator) {
1761  interleave(
1762      c, os, [&](const T &a) { os << a; }, separator);
1763}
1764 
1765template <typename Container, typename UnaryFunctor, typename StreamT,
1766          typename T = detail::ValueOfRange<Container>>
1767inline void interleaveComma(const Container &c, StreamT &os,
1768                            UnaryFunctor each_fn) {
1769  interleave(c, os, each_fn, ", ");
1770}
1771template <typename Container, typename StreamT,
1772          typename T = detail::ValueOfRange<Container>>
1773inline void interleaveComma(const Container &c, StreamT &os) {
1774  interleaveComma(c, os, [&](const T &a) { os << a; });
1775}
1776 
1777//===----------------------------------------------------------------------===//
1778//     Extra additions to <memory>
1779//===----------------------------------------------------------------------===//
1780 
1781struct FreeDeleter {
1782  void operator()(void* v) {
1783    ::free(v);
1784  }
1785};
1786 
1787template<typename First, typename Second>
1788struct pair_hash {
1789  size_t operator()(const std::pair<First, Second> &P) const {
1790    return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
1791  }
1792};
1793 
1794/// Binary functor that adapts to any other binary functor after dereferencing
1795/// operands.
1796template <typename T> struct deref {
1797  T func;
1798 
1799  // Could be further improved to cope with non-derivable functors and
1800  // non-binary functors (should be a variadic template member function
1801  // operator()).
1802  template <typename A, typename B> auto operator()(A &lhs, B &rhs) const {
1803    assert(lhs)((lhs) ? static_cast<void> (0) : __assert_fail ("lhs", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1803, __PRETTY_FUNCTION__));
1804    assert(rhs)((rhs) ? static_cast<void> (0) : __assert_fail ("rhs", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1804, __PRETTY_FUNCTION__));
1805    return func(*lhs, *rhs);
1806  }
1807};
1808 
1809namespace detail {
1810 
1811template <typename R> class enumerator_iter;
1812 
1813template <typename R> struct result_pair {
1814  using value_reference =
1815      typename std::iterator_traits<IterOfRange<R>>::reference;
1816 
1817  friend class enumerator_iter<R>;
1818 
1819  result_pair() = default;
1820  result_pair(std::size_t Index, IterOfRange<R> Iter)
1821      : Index(Index), Iter(Iter) {}
1822 
1823  result_pair<R>(const result_pair<R> &Other)
1824      : Index(Other.Index), Iter(Other.Iter) {}
1825  result_pair<R> &operator=(const result_pair<R> &Other) {
1826    Index = Other.Index;
1827    Iter = Other.Iter;
1828    return *this;
1829  }
1830 
1831  std::size_t index() const { return Index; }
1832  const value_reference value() const { return *Iter; }
1833  value_reference value() { return *Iter; }
1834 
1835private:
1836  std::size_t Index = std::numeric_limits<std::size_t>::max();
1837  IterOfRange<R> Iter;
1838};
1839 
1840template <typename R>
1841class enumerator_iter
1842    : public iterator_facade_base<
1843          enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
1844          typename std::iterator_traits<IterOfRange<R>>::difference_type,
1845          typename std::iterator_traits<IterOfRange<R>>::pointer,
1846          typename std::iterator_traits<IterOfRange<R>>::reference> {
1847  using result_type = result_pair<R>;
1848 
1849public:
1850  explicit enumerator_iter(IterOfRange<R> EndIter)
1851      : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1852 
1853  enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1854      : Result(Index, Iter) {}
1855 
1856  result_type &operator*() { return Result; }
1857  const result_type &operator*() const { return Result; }
1858 
1859  enumerator_iter<R> &operator++() {
1860    assert(Result.Index != std::numeric_limits<size_t>::max())((Result.Index != std::numeric_limits<size_t>::max()) ?
 static_cast<void> (0) : __assert_fail ("Result.Index != std::numeric_limits<size_t>::max()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1860, __PRETTY_FUNCTION__));
1861    ++Result.Iter;
1862    ++Result.Index;
1863    return *this;
1864  }
1865 
1866  bool operator==(const enumerator_iter<R> &RHS) const {
1867    // Don't compare indices here, only iterators.  It's possible for an end
1868    // iterator to have different indices depending on whether it was created
1869    // by calling std::end() versus incrementing a valid iterator.
1870    return Result.Iter == RHS.Result.Iter;
1871  }
1872 
1873  enumerator_iter<R>(const enumerator_iter<R> &Other) : Result(Other.Result) {}
1874  enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1875    Result = Other.Result;
1876    return *this;
1877  }
1878 
1879private:
1880  result_type Result;
1881};
1882 
1883template <typename R> class enumerator {
1884public:
1885  explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1886 
1887  enumerator_iter<R> begin() {
1888    return enumerator_iter<R>(0, std::begin(TheRange));
1889  }
1890 
1891  enumerator_iter<R> end() {
1892    return enumerator_iter<R>(std::end(TheRange));
1893  }
1894 
1895private:
1896  R TheRange;
1897};
1898 
1899} // end namespace detail
1900 
1901/// Given an input range, returns a new range whose values are are pair (A,B)
1902/// such that A is the 0-based index of the item in the sequence, and B is
1903/// the value from the original sequence.  Example:
1904///
1905/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1906/// for (auto X : enumerate(Items)) {
1907///   printf("Item %d - %c\n", X.index(), X.value());
1908/// }
1909///
1910/// Output:
1911///   Item 0 - A
1912///   Item 1 - B
1913///   Item 2 - C
1914///   Item 3 - D
1915///
1916template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1917  return detail::enumerator<R>(std::forward<R>(TheRange));
1918}
1919 
1920namespace detail {
1921 
1922template <typename F, typename Tuple, std::size_t... I>
1923decltype(auto) apply_tuple_impl(F &&f, Tuple &&t, std::index_sequence<I...>) {
1924  return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1925}
1926 
1927} // end namespace detail
1928 
1929/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1930/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1931/// return the result.
1932template <typename F, typename Tuple>
1933decltype(auto) apply_tuple(F &&f, Tuple &&t) {
1934  using Indices = std::make_index_sequence<
1935      std::tuple_size<typename std::decay<Tuple>::type>::value>;
1936 
1937  return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1938                                  Indices{});
1939}
1940 
1941/// Return true if the sequence [Begin, End) has exactly N items. Runs in O(N)
1942/// time. Not meant for use with random-access iterators.
1943/// Can optionally take a predicate to filter lazily some items.
1944template <typename IterTy,
1945          typename Pred = bool (*)(const decltype(*std::declval<IterTy>()) &)>
1946bool hasNItems(
1947    IterTy &&Begin, IterTy &&End, unsigned N,
1948    Pred &&ShouldBeCounted =
1949        [](const decltype(*std::declval<IterTy>()) &) { return true; },
1950    std::enable_if_t<
1951        !std::is_base_of<std::random_access_iterator_tag,
1952                         typename std::iterator_traits<std::remove_reference_t<
1953                             decltype(Begin)>>::iterator_category>::value,
1954        void> * = nullptr) {
1955  for (; N; ++Begin) {
1956    if (Begin == End)
1957      return false; // Too few.
1958    N -= ShouldBeCounted(*Begin);
1959  }
1960  for (; Begin != End; ++Begin)
1961    if (ShouldBeCounted(*Begin))
1962      return false; // Too many.
1963  return true;
1964}
1965 
1966/// Return true if the sequence [Begin, End) has N or more items. Runs in O(N)
1967/// time. Not meant for use with random-access iterators.
1968/// Can optionally take a predicate to lazily filter some items.
1969template <typename IterTy,
1970          typename Pred = bool (*)(const decltype(*std::declval<IterTy>()) &)>
1971bool hasNItemsOrMore(
1972    IterTy &&Begin, IterTy &&End, unsigned N,
1973    Pred &&ShouldBeCounted =
1974        [](const decltype(*std::declval<IterTy>()) &) { return true; },
1975    std::enable_if_t<
1976        !std::is_base_of<std::random_access_iterator_tag,
1977                         typename std::iterator_traits<std::remove_reference_t<
1978                             decltype(Begin)>>::iterator_category>::value,
1979        void> * = nullptr) {
1980  for (; N; ++Begin) {
1981    if (Begin == End)
1982      return false; // Too few.
1983    N -= ShouldBeCounted(*Begin);
1984  }
1985  return true;
1986}
1987 
1988/// Returns true if the sequence [Begin, End) has N or less items. Can
1989/// optionally take a predicate to lazily filter some items.
1990template <typename IterTy,
1991          typename Pred = bool (*)(const decltype(*std::declval<IterTy>()) &)>
1992bool hasNItemsOrLess(
1993    IterTy &&Begin, IterTy &&End, unsigned N,
1994    Pred &&ShouldBeCounted = [](const decltype(*std::declval<IterTy>()) &) {
1995      return true;
1996    }) {
1997  assert(N != std::numeric_limits<unsigned>::max())((N != std::numeric_limits<unsigned>::max()) ? static_cast
<void> (0) : __assert_fail ("N != std::numeric_limits<unsigned>::max()"
, "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/STLExtras.h"
, 1997, __PRETTY_FUNCTION__));
1998  return !hasNItemsOrMore(Begin, End, N + 1, ShouldBeCounted);
1999}
2000 
2001/// Returns true if the given container has exactly N items
2002template <typename ContainerTy> bool hasNItems(ContainerTy &&C, unsigned N) {
2003  return hasNItems(std::begin(C), std::end(C), N);
2004}
2005 
2006/// Returns true if the given container has N or more items
2007template <typename ContainerTy>
2008bool hasNItemsOrMore(ContainerTy &&C, unsigned N) {
2009  return hasNItemsOrMore(std::begin(C), std::end(C), N);
2010}
2011 
2012/// Returns true if the given container has N or less items
2013template <typename ContainerTy>
2014bool hasNItemsOrLess(ContainerTy &&C, unsigned N) {
2015  return hasNItemsOrLess(std::begin(C), std::end(C), N);
2016}
2017 
2018/// Returns a raw pointer that represents the same address as the argument.
2019///
2020/// This implementation can be removed once we move to C++20 where it's defined
2021/// as std::to_address().
2022///
2023/// The std::pointer_traits<>::to_address(p) variations of these overloads has
2024/// not been implemented.
2025template <class Ptr> auto to_address(const Ptr &P) { return P.operator->(); }
2026template <class T> constexpr T *to_address(T *P) { return P; }
2027 
2028} // end namespace llvm
2029 
2030#endif // LLVM_ADT_STLEXTRAS_H

←

/usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/bits/stl_algo.h

→

1// Algorithm implementation -*- C++ -*-

3// Copyright (C) 2001-2016 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.

11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14// GNU General Public License for more details.

16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.

20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23// <http://www.gnu.org/licenses/>.

25/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation.  Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose.  It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation.  Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose.  It is provided "as is" without express or implied warranty.
*/

51/** @file bits/stl_algo.h
*  This is an internal header file, included by other library headers.
*  Do not attempt to use it directly. @headername{algorithm}
*/

56#ifndef _STL_ALGO_H1
57#define _STL_ALGO_H1 1

59#include <cstdlib>	     // for rand
60#include <bits/algorithmfwd.h>
61#include <bits/stl_heap.h>
62#include <bits/stl_tempbuf.h>  // for _Temporary_buffer
63#include <bits/predefined_ops.h>

65#if __cplusplus201402L >= 201103L
66#include <bits/uniform_int_dist.h>
67#endif

69// See concept_check.h for the __glibcxx_*_requires macros.

71namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
72{
73_GLIBCXX_BEGIN_NAMESPACE_VERSION

/// Swaps the median value of *__a, *__b and *__c under __comp to *__result
template<typename _Iterator, typename _Compare>
  void
  __move_median_to_first(_Iterator __result,_Iterator __a, _Iterator __b,
	   _Iterator __c, _Compare __comp)
  {
    if (__comp(__a, __b))
{
 if (__comp(__b, __c))
   std::iter_swap(__result, __b);
 else if (__comp(__a, __c))
   std::iter_swap(__result, __c);
 else
   std::iter_swap(__result, __a);
}
    else if (__comp(__a, __c))
std::iter_swap(__result, __a);
    else if (__comp(__b, __c))
std::iter_swap(__result, __c);
    else
std::iter_swap(__result, __b);
  }

/// This is an overload used by find algos for the Input Iterator case.
template<typename _InputIterator, typename _Predicate>
  inline _InputIterator
  __find_if(_InputIterator __first, _InputIterator __last,
     _Predicate __pred, input_iterator_tag)
  {
    while (__first != __last && !__pred(__first))
++__first;
    return __first;
  }

/// This is an overload used by find algos for the RAI case.
template<typename _RandomAccessIterator, typename _Predicate>
  _RandomAccessIterator
  __find_if(_RandomAccessIterator __first, _RandomAccessIterator __last,
     _Predicate __pred, random_access_iterator_tag)
  {
    typename iterator_traits<_RandomAccessIterator>::difference_type
__trip_count = (__last - __first) >> 2;

    for (; __trip_count > 0; --__trip_count)
{
 if (__pred(__first))
   return __first;
 ++__first;

 if (__pred(__first))
   return __first;
 ++__first;

 if (__pred(__first))
   return __first;
 ++__first;

 if (__pred(__first))
   return __first;
 ++__first;
}

    switch (__last - __first)
{
case 3:
 if (__pred(__first))
   return __first;
 ++__first;
case 2:
 if (__pred(__first))
   return __first;
 ++__first;
case 1:
 if (__pred(__first))
   return __first;
 ++__first;
case 0:
default:
 return __last;
}
  }

template<typename _Iterator, typename _Predicate>
  inline _Iterator
  __find_if(_Iterator __first, _Iterator __last, _Predicate __pred)
  {
    return __find_if(__first, __last, __pred,
       std::__iterator_category(__first));
  }

/// Provided for stable_partition to use.
template<typename _InputIterator, typename _Predicate>
  inline _InputIterator
  __find_if_not(_InputIterator __first, _InputIterator __last,
  _Predicate __pred)
  {
    return std::__find_if(__first, __last,
	    __gnu_cxx::__ops::__negate(__pred),
	    std::__iterator_category(__first));
  }

/// Like find_if_not(), but uses and updates a count of the
/// remaining range length instead of comparing against an end
/// iterator.
template<typename _InputIterator, typename _Predicate, typename _Distance>
  _InputIterator
  __find_if_not_n(_InputIterator __first, _Distance& __len, _Predicate __pred)
  {
    for (; __len; --__len, ++__first)
if (!__pred(__first))
 break;
    return __first;
  }

// set_difference
// set_intersection
// set_symmetric_difference
// set_union
// for_each
// find
// find_if
// find_first_of
// adjacent_find
// count
// count_if
// search

template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  _ForwardIterator1
  __search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
    _ForwardIterator2 __first2, _ForwardIterator2 __last2,
    _BinaryPredicate  __predicate)
  {
    // Test for empty ranges
    if (__first1 == __last1 || __first2 == __last2)
return __first1;

    // Test for a pattern of length 1.
    _ForwardIterator2 __p1(__first2);
    if (++__p1 == __last2)
return std::__find_if(__first1, __last1,
__gnu_cxx::__ops::__iter_comp_iter(__predicate, __first2));

    // General case.
    _ForwardIterator2 __p;
    _ForwardIterator1 __current = __first1;

    for (;;)
{
 __first1 =
   std::__find_if(__first1, __last1,
__gnu_cxx::__ops::__iter_comp_iter(__predicate, __first2));

 if (__first1 == __last1)
   return __last1;

 __p = __p1;
 __current = __first1;
 if (++__current == __last1)
   return __last1;

 while (__predicate(__current, __p))
   {
     if (++__p == __last2)
return __first1;
     if (++__current == __last1)
return __last1;
   }
 ++__first1;
}
    return __first1;
  }

// search_n

/**
 *  This is an helper function for search_n overloaded for forward iterators.
*/
template<typename _ForwardIterator, typename _Integer,
  typename _UnaryPredicate>
  _ForwardIterator
  __search_n_aux(_ForwardIterator __first, _ForwardIterator __last,
   _Integer __count, _UnaryPredicate __unary_pred,
   std::forward_iterator_tag)
  {
    __first = std::__find_if(__first, __last, __unary_pred);
    while (__first != __last)
{
 typename iterator_traits<_ForwardIterator>::difference_type
   __n = __count;
 _ForwardIterator __i = __first;
 ++__i;
 while (__i != __last && __n != 1 && __unary_pred(__i))
   {
     ++__i;
     --__n;
   }
 if (__n == 1)
   return __first;
 if (__i == __last)
   return __last;
 __first = std::__find_if(++__i, __last, __unary_pred);
}
    return __last;
  }

/**
 *  This is an helper function for search_n overloaded for random access
 *  iterators.
*/
template<typename _RandomAccessIter, typename _Integer,
  typename _UnaryPredicate>
  _RandomAccessIter
  __search_n_aux(_RandomAccessIter __first, _RandomAccessIter __last,
   _Integer __count, _UnaryPredicate __unary_pred,
   std::random_access_iterator_tag)
  {
    typedef typename std::iterator_traits<_RandomAccessIter>::difference_type
_DistanceType;

    _DistanceType __tailSize = __last - __first;
    _DistanceType __remainder = __count;

    while (__remainder <= __tailSize) // the main loop...
{
 __first += __remainder;
 __tailSize -= __remainder;
 // __first here is always pointing to one past the last element of
 // next possible match.
 _RandomAccessIter __backTrack = __first; 
 while (__unary_pred(--__backTrack))
   {
     if (--__remainder == 0)
return (__first - __count); // Success
   }
 __remainder = __count + 1 - (__first - __backTrack);
}
    return __last; // Failure
  }

template<typename _ForwardIterator, typename _Integer,
  typename _UnaryPredicate>
  _ForwardIterator
  __search_n(_ForwardIterator __first, _ForwardIterator __last,
      _Integer __count,
      _UnaryPredicate __unary_pred)
  {
    if (__count <= 0)
return __first;

    if (__count == 1)
return std::__find_if(__first, __last, __unary_pred);

    return std::__search_n_aux(__first, __last, __count, __unary_pred,
		 std::__iterator_category(__first));
  }

// find_end for forward iterators.
template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  _ForwardIterator1
  __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
      _ForwardIterator2 __first2, _ForwardIterator2 __last2,
      forward_iterator_tag, forward_iterator_tag,
      _BinaryPredicate __comp)
  {
    if (__first2 == __last2)
return __last1;

    _ForwardIterator1 __result = __last1;
    while (1)
{
 _ForwardIterator1 __new_result
   = std::__search(__first1, __last1, __first2, __last2, __comp);
 if (__new_result == __last1)
   return __result;
 else
   {
     __result = __new_result;
     __first1 = __new_result;
     ++__first1;
   }
}
  }

// find_end for bidirectional iterators (much faster).
template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
  typename _BinaryPredicate>
  _BidirectionalIterator1
  __find_end(_BidirectionalIterator1 __first1,
      _BidirectionalIterator1 __last1,
      _BidirectionalIterator2 __first2,
      _BidirectionalIterator2 __last2,
      bidirectional_iterator_tag, bidirectional_iterator_tag,
      _BinaryPredicate __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator1>)
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator2>)

    typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1;
    typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2;

    _RevIterator1 __rlast1(__first1);
    _RevIterator2 __rlast2(__first2);
    _RevIterator1 __rresult = std::__search(_RevIterator1(__last1), __rlast1,
			      _RevIterator2(__last2), __rlast2,
			      __comp);

    if (__rresult == __rlast1)
return __last1;
    else
{
 _BidirectionalIterator1 __result = __rresult.base();
 std::advance(__result, -std::distance(__first2, __last2));
 return __result;
}
  }

/**
 *  @brief  Find last matching subsequence in a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of range to search.
 *  @param  __last1   End of range to search.
 *  @param  __first2  Start of sequence to match.
 *  @param  __last2   End of sequence to match.
 *  @return   The last iterator @c i in the range
 *  @p [__first1,__last1-(__last2-__first2)) such that @c *(i+N) ==
 *  @p *(__first2+N) for each @c N in the range @p
 *  [0,__last2-__first2), or @p __last1 if no such iterator exists.
 *
 *  Searches the range @p [__first1,__last1) for a sub-sequence that
 *  compares equal value-by-value with the sequence given by @p
 *  [__first2,__last2) and returns an iterator to the __first
 *  element of the sub-sequence, or @p __last1 if the sub-sequence
 *  is not found.  The sub-sequence will be the last such
 *  subsequence contained in [__first1,__last1).
 *
 *  Because the sub-sequence must lie completely within the range @p
 *  [__first1,__last1) it must start at a position less than @p
 *  __last1-(__last2-__first2) where @p __last2-__first2 is the
 *  length of the sub-sequence.  This means that the returned
 *  iterator @c i will be in the range @p
 *  [__first1,__last1-(__last2-__first2))
*/
template<typename _ForwardIterator1, typename _ForwardIterator2>
  inline _ForwardIterator1
  find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
    _ForwardIterator2 __first2, _ForwardIterator2 __last2)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_ForwardIterator1>::value_type,
   typename iterator_traits<_ForwardIterator2>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    return std::__find_end(__first1, __last1, __first2, __last2,
	     std::__iterator_category(__first1),
	     std::__iterator_category(__first2),
	     __gnu_cxx::__ops::__iter_equal_to_iter());
  }

/**
 *  @brief  Find last matching subsequence in a sequence using a predicate.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of range to search.
 *  @param  __last1   End of range to search.
 *  @param  __first2  Start of sequence to match.
 *  @param  __last2   End of sequence to match.
 *  @param  __comp    The predicate to use.
 *  @return The last iterator @c i in the range @p
 *  [__first1,__last1-(__last2-__first2)) such that @c
 *  predicate(*(i+N), @p (__first2+N)) is true for each @c N in the
 *  range @p [0,__last2-__first2), or @p __last1 if no such iterator
 *  exists.
 *
 *  Searches the range @p [__first1,__last1) for a sub-sequence that
 *  compares equal value-by-value with the sequence given by @p
 *  [__first2,__last2) using comp as a predicate and returns an
 *  iterator to the first element of the sub-sequence, or @p __last1
 *  if the sub-sequence is not found.  The sub-sequence will be the
 *  last such subsequence contained in [__first,__last1).
 *
 *  Because the sub-sequence must lie completely within the range @p
 *  [__first1,__last1) it must start at a position less than @p
 *  __last1-(__last2-__first2) where @p __last2-__first2 is the
 *  length of the sub-sequence.  This means that the returned
 *  iterator @c i will be in the range @p
 *  [__first1,__last1-(__last2-__first2))
*/
template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  inline _ForwardIterator1
  find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
    _ForwardIterator2 __first2, _ForwardIterator2 __last2,
    _BinaryPredicate __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
   typename iterator_traits<_ForwardIterator1>::value_type,
   typename iterator_traits<_ForwardIterator2>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    return std::__find_end(__first1, __last1, __first2, __last2,
	     std::__iterator_category(__first1),
	     std::__iterator_category(__first2),
	     __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

493#if __cplusplus201402L >= 201103L
/**
 *  @brief  Checks that a predicate is true for all the elements
 *          of a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __pred    A predicate.
 *  @return  True if the check is true, false otherwise.
 *
 *  Returns true if @p __pred is true for each element in the range
 *  @p [__first,__last), and false otherwise.
*/
template<typename _InputIterator, typename _Predicate>
  inline bool
  all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
  { return __last == std::find_if_not(__first, __last, __pred); }

/**
 *  @brief  Checks that a predicate is false for all the elements
 *          of a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __pred    A predicate.
 *  @return  True if the check is true, false otherwise.
 *
 *  Returns true if @p __pred is false for each element in the range
 *  @p [__first,__last), and false otherwise.
*/
template<typename _InputIterator, typename _Predicate>
  inline bool
  none_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
  { return __last == _GLIBCXX_STD_Astd::find_if(__first, __last, __pred); }
24
←
Calling 'operator=='→
26
←
Returning from 'operator=='→
27
←
Returning the value 1, which participates in a condition later→

/**
 *  @brief  Checks that a predicate is false for at least an element
 *          of a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __pred    A predicate.
 *  @return  True if the check is true, false otherwise.
 *
 *  Returns true if an element exists in the range @p
 *  [__first,__last) such that @p __pred is true, and false
 *  otherwise.
*/
template<typename _InputIterator, typename _Predicate>
  inline bool
  any_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
  { return !std::none_of(__first, __last, __pred); }
23
←
Calling 'none_of<llvm::ilist_iterator<llvm::ilist_detail::node_options<llvm::Instruction, true, false, void>, false, false>, (lambda at /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp:2915:19)>'→
28
←
Returning from 'none_of<llvm::ilist_iterator<llvm::ilist_detail::node_options<llvm::Instruction, true, false, void>, false, false>, (lambda at /build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp:2915:19)>'→
29
←
Returning zero, which participates in a condition later→

/**
 *  @brief  Find the first element in a sequence for which a
 *          predicate is false.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __pred   A predicate.
 *  @return   The first iterator @c i in the range @p [__first,__last)
 *  such that @p __pred(*i) is false, or @p __last if no such iterator exists.
*/
template<typename _InputIterator, typename _Predicate>
  inline _InputIterator
  find_if_not(_InputIterator __first, _InputIterator __last,
_Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
     typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    return std::__find_if_not(__first, __last,
		__gnu_cxx::__ops::__pred_iter(__pred));
  }

/**
 *  @brief  Checks whether the sequence is partitioned.
 *  @ingroup mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __pred   A predicate.
 *  @return  True if the range @p [__first,__last) is partioned by @p __pred,
 *  i.e. if all elements that satisfy @p __pred appear before those that
 *  do not.
*/
template<typename _InputIterator, typename _Predicate>
  inline bool
  is_partitioned(_InputIterator __first, _InputIterator __last,
   _Predicate __pred)
  {
    __first = std::find_if_not(__first, __last, __pred);
    return std::none_of(__first, __last, __pred);
  }

/**
 *  @brief  Find the partition point of a partitioned range.
 *  @ingroup mutating_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __pred    A predicate.
 *  @return  An iterator @p mid such that @p all_of(__first, mid, __pred)
 *           and @p none_of(mid, __last, __pred) are both true.
*/
template<typename _ForwardIterator, typename _Predicate>
  _ForwardIterator
  partition_point(_ForwardIterator __first, _ForwardIterator __last,
    _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
     typename iterator_traits<_ForwardIterator>::value_type>)

    // A specific debug-mode test will be necessary...
    __glibcxx_requires_valid_range(__first, __last);

    typedef typename iterator_traits<_ForwardIterator>::difference_type
_DistanceType;

    _DistanceType __len = std::distance(__first, __last);
    _DistanceType __half;
    _ForwardIterator __middle;

    while (__len > 0)
{
 __half = __len >> 1;
 __middle = __first;
 std::advance(__middle, __half);
 if (__pred(*__middle))
   {
     __first = __middle;
     ++__first;
     __len = __len - __half - 1;
   }
 else
   __len = __half;
}
    return __first;
  }
634#endif

template<typename _InputIterator, typename _OutputIterator,
  typename _Predicate>
  _OutputIterator
  __remove_copy_if(_InputIterator __first, _InputIterator __last,
     _OutputIterator __result, _Predicate __pred)
  {
    for (; __first != __last; ++__first)
if (!__pred(__first))
 {
   *__result = *__first;
   ++__result;
 }
    return __result;
  }

/**
 *  @brief Copy a sequence, removing elements of a given value.
 *  @ingroup mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __result  An output iterator.
 *  @param  __value   The value to be removed.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  Copies each element in the range @p [__first,__last) not equal
 *  to @p __value to the range beginning at @p __result.
 *  remove_copy() is stable, so the relative order of elements that
 *  are copied is unchanged.
*/
template<typename _InputIterator, typename _OutputIterator, typename _Tp>
  inline _OutputIterator
  remove_copy(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, const _Tp& __value)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_InputIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__remove_copy_if(__first, __last, __result,
__gnu_cxx::__ops::__iter_equals_val(__value));
  }

/**
 *  @brief Copy a sequence, removing elements for which a predicate is true.
 *  @ingroup mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __result  An output iterator.
 *  @param  __pred    A predicate.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  Copies each element in the range @p [__first,__last) for which
 *  @p __pred returns false to the range beginning at @p __result.
 *
 *  remove_copy_if() is stable, so the relative order of elements that are
 *  copied is unchanged.
*/
template<typename _InputIterator, typename _OutputIterator,
  typename _Predicate>
  inline _OutputIterator
  remove_copy_if(_InputIterator __first, _InputIterator __last,
   _OutputIterator __result, _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__remove_copy_if(__first, __last, __result,
		   __gnu_cxx::__ops::__pred_iter(__pred));
  }

715#if __cplusplus201402L >= 201103L
/**
 *  @brief Copy the elements of a sequence for which a predicate is true.
 *  @ingroup mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __result  An output iterator.
 *  @param  __pred    A predicate.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  Copies each element in the range @p [__first,__last) for which
 *  @p __pred returns true to the range beginning at @p __result.
 *
 *  copy_if() is stable, so the relative order of elements that are
 *  copied is unchanged.
*/
template<typename _InputIterator, typename _OutputIterator,
  typename _Predicate>
  _OutputIterator
  copy_if(_InputIterator __first, _InputIterator __last,
   _OutputIterator __result, _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    for (; __first != __last; ++__first)
if (__pred(*__first))
 {
   *__result = *__first;
   ++__result;
 }
    return __result;
  }

template<typename _InputIterator, typename _Size, typename _OutputIterator>
  _OutputIterator
  __copy_n(_InputIterator __first, _Size __n,
    _OutputIterator __result, input_iterator_tag)
  {
    if (__n > 0)
{
 while (true)
   {
     *__result = *__first;
     ++__result;
     if (--__n > 0)
++__first;
     else
break;
   }
}
    return __result;
  }

template<typename _RandomAccessIterator, typename _Size,
  typename _OutputIterator>
  inline _OutputIterator
  __copy_n(_RandomAccessIterator __first, _Size __n,
    _OutputIterator __result, random_access_iterator_tag)
  { return std::copy(__first, __first + __n, __result); }

/**
 *  @brief Copies the range [first,first+n) into [result,result+n).
 *  @ingroup mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __n      The number of elements to copy.
 *  @param  __result An output iterator.
 *  @return  result+n.
 *
 *  This inline function will boil down to a call to @c memmove whenever
 *  possible.  Failing that, if random access iterators are passed, then the
 *  loop count will be known (and therefore a candidate for compiler
 *  optimizations such as unrolling).
*/
template<typename _InputIterator, typename _Size, typename _OutputIterator>
  inline _OutputIterator
  copy_n(_InputIterator __first, _Size __n, _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)

    return std::__copy_n(__first, __n, __result,
	   std::__iterator_category(__first));
  }

/**
 *  @brief Copy the elements of a sequence to separate output sequences
 *         depending on the truth value of a predicate.
 *  @ingroup mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __out_true   An output iterator.
 *  @param  __out_false  An output iterator.
 *  @param  __pred    A predicate.
 *  @return   A pair designating the ends of the resulting sequences.
 *
 *  Copies each element in the range @p [__first,__last) for which
 *  @p __pred returns true to the range beginning at @p out_true
 *  and each element for which @p __pred returns false to @p __out_false.
*/
template<typename _InputIterator, typename _OutputIterator1,
  typename _OutputIterator2, typename _Predicate>
  pair<_OutputIterator1, _OutputIterator2>
  partition_copy(_InputIterator __first, _InputIterator __last,
   _OutputIterator1 __out_true, _OutputIterator2 __out_false,
   _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator1,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator2,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    
    for (; __first != __last; ++__first)
if (__pred(*__first))
 {
   *__out_true = *__first;
   ++__out_true;
 }
else
 {
   *__out_false = *__first;
   ++__out_false;
 }

    return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
  }
853#endif

template<typename _ForwardIterator, typename _Predicate>
  _ForwardIterator
  __remove_if(_ForwardIterator __first, _ForwardIterator __last,
_Predicate __pred)
  {
    __first = std::__find_if(__first, __last, __pred);
    if (__first == __last)
return __first;
    _ForwardIterator __result = __first;
    ++__first;
    for (; __first != __last; ++__first)
if (!__pred(__first))
 {
   *__result = _GLIBCXX_MOVE(*__first)std::move(*__first);
   ++__result;
 }
    return __result;
  }

/**
 *  @brief Remove elements from a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __value  The value to be removed.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  All elements equal to @p __value are removed from the range
 *  @p [__first,__last).
 *
 *  remove() is stable, so the relative order of elements that are
 *  not removed is unchanged.
 *
 *  Elements between the end of the resulting sequence and @p __last
 *  are still present, but their value is unspecified.
*/
template<typename _ForwardIterator, typename _Tp>
  inline _ForwardIterator
  remove(_ForwardIterator __first, _ForwardIterator __last,
  const _Tp& __value)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__remove_if(__first, __last,
__gnu_cxx::__ops::__iter_equals_val(__value));
  }

/**
 *  @brief Remove elements from a sequence using a predicate.
 *  @ingroup mutating_algorithms
 *  @param  __first  A forward iterator.
 *  @param  __last   A forward iterator.
 *  @param  __pred   A predicate.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  All elements for which @p __pred returns true are removed from the range
 *  @p [__first,__last).
 *
 *  remove_if() is stable, so the relative order of elements that are
 *  not removed is unchanged.
 *
 *  Elements between the end of the resulting sequence and @p __last
 *  are still present, but their value is unspecified.
*/
template<typename _ForwardIterator, typename _Predicate>
  inline _ForwardIterator
  remove_if(_ForwardIterator __first, _ForwardIterator __last,
     _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__remove_if(__first, __last,
	      __gnu_cxx::__ops::__pred_iter(__pred));
  }

template<typename _ForwardIterator, typename _BinaryPredicate>
  _ForwardIterator
  __adjacent_find(_ForwardIterator __first, _ForwardIterator __last,
    _BinaryPredicate __binary_pred)
  {
    if (__first == __last)
return __last;
    _ForwardIterator __next = __first;
    while (++__next != __last)
{
 if (__binary_pred(__first, __next))
   return __first;
 __first = __next;
}
    return __last;
  }

template<typename _ForwardIterator, typename _BinaryPredicate>
  _ForwardIterator
  __unique(_ForwardIterator __first, _ForwardIterator __last,
    _BinaryPredicate __binary_pred)
  {
    // Skip the beginning, if already unique.
    __first = std::__adjacent_find(__first, __last, __binary_pred);
    if (__first == __last)
return __last;

    // Do the real copy work.
    _ForwardIterator __dest = __first;
    ++__first;
    while (++__first != __last)
if (!__binary_pred(__dest, __first))
 *++__dest = _GLIBCXX_MOVE(*__first)std::move(*__first);
    return ++__dest;
  }

/**
 *  @brief Remove consecutive duplicate values from a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first  A forward iterator.
 *  @param  __last   A forward iterator.
 *  @return  An iterator designating the end of the resulting sequence.
 *
 *  Removes all but the first element from each group of consecutive
 *  values that compare equal.
 *  unique() is stable, so the relative order of elements that are
 *  not removed is unchanged.
 *  Elements between the end of the resulting sequence and @p __last
 *  are still present, but their value is unspecified.
*/
template<typename _ForwardIterator>
  inline _ForwardIterator
  unique(_ForwardIterator __first, _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_EqualityComparableConcept<
     typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__unique(__first, __last,
	   __gnu_cxx::__ops::__iter_equal_to_iter());
  }

/**
 *  @brief Remove consecutive values from a sequence using a predicate.
 *  @ingroup mutating_algorithms
 *  @param  __first        A forward iterator.
 *  @param  __last         A forward iterator.
 *  @param  __binary_pred  A binary predicate.
 *  @return  An iterator designating the end of the resulting sequence.
 *
 *  Removes all but the first element from each group of consecutive
 *  values for which @p __binary_pred returns true.
 *  unique() is stable, so the relative order of elements that are
 *  not removed is unchanged.
 *  Elements between the end of the resulting sequence and @p __last
 *  are still present, but their value is unspecified.
*/
template<typename _ForwardIterator, typename _BinaryPredicate>
  inline _ForwardIterator
  unique(_ForwardIterator __first, _ForwardIterator __last,
  _BinaryPredicate __binary_pred)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
typename iterator_traits<_ForwardIterator>::value_type,
typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__unique(__first, __last,
	   __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
  }

/**
 *  This is an uglified
 *  unique_copy(_InputIterator, _InputIterator, _OutputIterator,
 *              _BinaryPredicate)
 *  overloaded for forward iterators and output iterator as result.
*/
template<typename _ForwardIterator, typename _OutputIterator,
  typename _BinaryPredicate>
  _OutputIterator
  __unique_copy(_ForwardIterator __first, _ForwardIterator __last,
  _OutputIterator __result, _BinaryPredicate __binary_pred,
  forward_iterator_tag, output_iterator_tag)
  {
    // concept requirements -- iterators already checked
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
 typename iterator_traits<_ForwardIterator>::value_type,
 typename iterator_traits<_ForwardIterator>::value_type>)

    _ForwardIterator __next = __first;
    *__result = *__first;
    while (++__next != __last)
if (!__binary_pred(__first, __next))
 {
   __first = __next;
   *++__result = *__first;
 }
    return ++__result;
  }

/**
 *  This is an uglified
 *  unique_copy(_InputIterator, _InputIterator, _OutputIterator,
 *              _BinaryPredicate)
 *  overloaded for input iterators and output iterator as result.
*/
template<typename _InputIterator, typename _OutputIterator,
  typename _BinaryPredicate>
  _OutputIterator
  __unique_copy(_InputIterator __first, _InputIterator __last,
  _OutputIterator __result, _BinaryPredicate __binary_pred,
  input_iterator_tag, output_iterator_tag)
  {
    // concept requirements -- iterators already checked
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
 typename iterator_traits<_InputIterator>::value_type,
 typename iterator_traits<_InputIterator>::value_type>)

    typename iterator_traits<_InputIterator>::value_type __value = *__first;
    __decltype(__gnu_cxx::__ops::__iter_comp_val(__binary_pred))
__rebound_pred
= __gnu_cxx::__ops::__iter_comp_val(__binary_pred);
    *__result = __value;
    while (++__first != __last)
if (!__rebound_pred(__first, __value))
 {
   __value = *__first;
   *++__result = __value;
 }
    return ++__result;
  }

/**
 *  This is an uglified
 *  unique_copy(_InputIterator, _InputIterator, _OutputIterator,
 *              _BinaryPredicate)
 *  overloaded for input iterators and forward iterator as result.
*/
template<typename _InputIterator, typename _ForwardIterator,
  typename _BinaryPredicate>
  _ForwardIterator
  __unique_copy(_InputIterator __first, _InputIterator __last,
  _ForwardIterator __result, _BinaryPredicate __binary_pred,
  input_iterator_tag, forward_iterator_tag)
  {
    // concept requirements -- iterators already checked
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
 typename iterator_traits<_ForwardIterator>::value_type,
 typename iterator_traits<_InputIterator>::value_type>)
    *__result = *__first;
    while (++__first != __last)
if (!__binary_pred(__result, __first))
 *++__result = *__first;
    return ++__result;
  }

/**
 *  This is an uglified reverse(_BidirectionalIterator,
 *                              _BidirectionalIterator)
 *  overloaded for bidirectional iterators.
*/
template<typename _BidirectionalIterator>
  void
  __reverse(_BidirectionalIterator __first, _BidirectionalIterator __last,
     bidirectional_iterator_tag)
  {
    while (true)
if (__first == __last || __first == --__last)
 return;
else
 {
   std::iter_swap(__first, __last);
   ++__first;
 }
  }

/**
 *  This is an uglified reverse(_BidirectionalIterator,
 *                              _BidirectionalIterator)
 *  overloaded for random access iterators.
*/
template<typename _RandomAccessIterator>
  void
  __reverse(_RandomAccessIterator __first, _RandomAccessIterator __last,
     random_access_iterator_tag)
  {
    if (__first == __last)
return;
    --__last;
    while (__first < __last)
{
 std::iter_swap(__first, __last);
 ++__first;
 --__last;
}
  }

/**
 *  @brief Reverse a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first  A bidirectional iterator.
 *  @param  __last   A bidirectional iterator.
 *  @return   reverse() returns no value.
 *
 *  Reverses the order of the elements in the range @p [__first,__last),
 *  so that the first element becomes the last etc.
 *  For every @c i such that @p 0<=i<=(__last-__first)/2), @p reverse()
 *  swaps @p *(__first+i) and @p *(__last-(i+1))
*/
template<typename _BidirectionalIterator>
  inline void
  reverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)
    __glibcxx_requires_valid_range(__first, __last);
    std::__reverse(__first, __last, std::__iterator_category(__first));
  }

/**
 *  @brief Copy a sequence, reversing its elements.
 *  @ingroup mutating_algorithms
 *  @param  __first   A bidirectional iterator.
 *  @param  __last    A bidirectional iterator.
 *  @param  __result  An output iterator.
 *  @return  An iterator designating the end of the resulting sequence.
 *
 *  Copies the elements in the range @p [__first,__last) to the
 *  range @p [__result,__result+(__last-__first)) such that the
 *  order of the elements is reversed.  For every @c i such that @p
 *  0<=i<=(__last-__first), @p reverse_copy() performs the
 *  assignment @p *(__result+(__last-__first)-1-i) = *(__first+i).
 *  The ranges @p [__first,__last) and @p
 *  [__result,__result+(__last-__first)) must not overlap.
*/
template<typename _BidirectionalIterator, typename _OutputIterator>
  _OutputIterator
  reverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last,
 _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    while (__first != __last)
{
 --__last;
 *__result = *__last;
 ++__result;
}
    return __result;
  }

/**
 *  This is a helper function for the rotate algorithm specialized on RAIs.
 *  It returns the greatest common divisor of two integer values.
*/
template<typename _EuclideanRingElement>
  _EuclideanRingElement
  __gcd(_EuclideanRingElement __m, _EuclideanRingElement __n)
  {
    while (__n != 0)
{
 _EuclideanRingElement __t = __m % __n;
 __m = __n;
 __n = __t;
}
    return __m;
  }

inline namespace _V2
{

/// This is a helper function for the rotate algorithm.
template<typename _ForwardIterator>
  _ForwardIterator
  __rotate(_ForwardIterator __first,
    _ForwardIterator __middle,
    _ForwardIterator __last,
    forward_iterator_tag)
  {
    if (__first == __middle)
return __last;
    else if (__last  == __middle)
return __first;

    _ForwardIterator __first2 = __middle;
    do
{
 std::iter_swap(__first, __first2);
 ++__first;
 ++__first2;
 if (__first == __middle)
   __middle = __first2;
}
    while (__first2 != __last);

    _ForwardIterator __ret = __first;

    __first2 = __middle;

    while (__first2 != __last)
{
 std::iter_swap(__first, __first2);
 ++__first;
 ++__first2;
 if (__first == __middle)
   __middle = __first2;
 else if (__first2 == __last)
   __first2 = __middle;
}
    return __ret;
  }

 /// This is a helper function for the rotate algorithm.
template<typename _BidirectionalIterator>
  _BidirectionalIterator
  __rotate(_BidirectionalIterator __first,
    _BidirectionalIterator __middle,
    _BidirectionalIterator __last,
     bidirectional_iterator_tag)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)

    if (__first == __middle)
return __last;
    else if (__last  == __middle)
return __first;

    std::__reverse(__first,  __middle, bidirectional_iterator_tag());
    std::__reverse(__middle, __last,   bidirectional_iterator_tag());

    while (__first != __middle && __middle != __last)
{
 std::iter_swap(__first, --__last);
 ++__first;
}

    if (__first == __middle)
{
 std::__reverse(__middle, __last,   bidirectional_iterator_tag());
 return __last;
}
    else
{
 std::__reverse(__first,  __middle, bidirectional_iterator_tag());
 return __first;
}
  }

/// This is a helper function for the rotate algorithm.
template<typename _RandomAccessIterator>
  _RandomAccessIterator
  __rotate(_RandomAccessIterator __first,
    _RandomAccessIterator __middle,
    _RandomAccessIterator __last,
    random_access_iterator_tag)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
		  _RandomAccessIterator>)

    if (__first == __middle)
return __last;
    else if (__last  == __middle)
return __first;

    typedef typename iterator_traits<_RandomAccessIterator>::difference_type
_Distance;
    typedef typename iterator_traits<_RandomAccessIterator>::value_type
_ValueType;

    _Distance __n = __last   - __first;
    _Distance __k = __middle - __first;

    if (__k == __n - __k)
{
 std::swap_ranges(__first, __middle, __middle);
 return __middle;
}

    _RandomAccessIterator __p = __first;
    _RandomAccessIterator __ret = __first + (__last - __middle);

    for (;;)
{
 if (__k < __n - __k)
   {
     if (__is_pod(_ValueType) && __k == 1)
{
  _ValueType __t = _GLIBCXX_MOVE(*__p)std::move(*__p);
  _GLIBCXX_MOVE3(__p + 1, __p + __n, __p)std::move(__p + 1, __p + __n, __p);
  *(__p + __n - 1) = _GLIBCXX_MOVE(__t)std::move(__t);
  return __ret;
}
     _RandomAccessIterator __q = __p + __k;
     for (_Distance __i = 0; __i < __n - __k; ++ __i)
{
  std::iter_swap(__p, __q);
  ++__p;
  ++__q;
}
     __n %= __k;
     if (__n == 0)
return __ret;
     std::swap(__n, __k);
     __k = __n - __k;
   }
 else
   {
     __k = __n - __k;
     if (__is_pod(_ValueType) && __k == 1)
{
  _ValueType __t = _GLIBCXX_MOVE(*(__p + __n - 1))std::move(*(__p + __n - 1));
  _GLIBCXX_MOVE_BACKWARD3(__p, __p + __n - 1, __p + __n)std::move_backward(__p, __p + __n - 1, __p + __n);
  *__p = _GLIBCXX_MOVE(__t)std::move(__t);
  return __ret;
}
     _RandomAccessIterator __q = __p + __n;
     __p = __q - __k;
     for (_Distance __i = 0; __i < __n - __k; ++ __i)
{
  --__p;
  --__q;
  std::iter_swap(__p, __q);
}
     __n %= __k;
     if (__n == 0)
return __ret;
     std::swap(__n, __k);
   }
}
  }

 // _GLIBCXX_RESOLVE_LIB_DEFECTS
 // DR 488. rotate throws away useful information
/**
 *  @brief Rotate the elements of a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __middle  A forward iterator.
 *  @param  __last    A forward iterator.
 *  @return  first + (last - middle).
 *
 *  Rotates the elements of the range @p [__first,__last) by 
 *  @p (__middle - __first) positions so that the element at @p __middle
 *  is moved to @p __first, the element at @p __middle+1 is moved to
 *  @p __first+1 and so on for each element in the range
 *  @p [__first,__last).
 *
 *  This effectively swaps the ranges @p [__first,__middle) and
 *  @p [__middle,__last).
 *
 *  Performs
 *   @p *(__first+(n+(__last-__middle))%(__last-__first))=*(__first+n)
 *  for each @p n in the range @p [0,__last-__first).
*/
template<typename _ForwardIterator>
  inline _ForwardIterator
  rotate(_ForwardIterator __first, _ForwardIterator __middle,
  _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_requires_valid_range(__first, __middle);
    __glibcxx_requires_valid_range(__middle, __last);

    return std::__rotate(__first, __middle, __last,
	   std::__iterator_category(__first));
  }

} // namespace _V2

/**
 *  @brief Copy a sequence, rotating its elements.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __middle  A forward iterator.
 *  @param  __last    A forward iterator.
 *  @param  __result  An output iterator.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  Copies the elements of the range @p [__first,__last) to the
 *  range beginning at @result, rotating the copied elements by 
 *  @p (__middle-__first) positions so that the element at @p __middle
 *  is moved to @p __result, the element at @p __middle+1 is moved
 *  to @p __result+1 and so on for each element in the range @p
 *  [__first,__last).
 *
 *  Performs 
 *  @p *(__result+(n+(__last-__middle))%(__last-__first))=*(__first+n)
 *  for each @p n in the range @p [0,__last-__first).
*/
template<typename _ForwardIterator, typename _OutputIterator>
  inline _OutputIterator
  rotate_copy(_ForwardIterator __first, _ForwardIterator __middle,
_ForwardIterator __last, _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __middle);
    __glibcxx_requires_valid_range(__middle, __last);

    return std::copy(__first, __middle,
       std::copy(__middle, __last, __result));
  }

/// This is a helper function...
template<typename _ForwardIterator, typename _Predicate>
  _ForwardIterator
  __partition(_ForwardIterator __first, _ForwardIterator __last,
_Predicate __pred, forward_iterator_tag)
  {
    if (__first == __last)
return __first;

    while (__pred(*__first))
if (++__first == __last)
 return __first;

    _ForwardIterator __next = __first;

    while (++__next != __last)
if (__pred(*__next))
 {
   std::iter_swap(__first, __next);
   ++__first;
 }

    return __first;
  }

/// This is a helper function...
template<typename _BidirectionalIterator, typename _Predicate>
  _BidirectionalIterator
  __partition(_BidirectionalIterator __first, _BidirectionalIterator __last,
_Predicate __pred, bidirectional_iterator_tag)
  {
    while (true)
{
 while (true)
   if (__first == __last)
     return __first;
   else if (__pred(*__first))
     ++__first;
   else
     break;
 --__last;
 while (true)
   if (__first == __last)
     return __first;
   else if (!bool(__pred(*__last)))
     --__last;
   else
     break;
 std::iter_swap(__first, __last);
 ++__first;
}
  }

// partition

/// This is a helper function...
/// Requires __first != __last and !__pred(__first)
/// and __len == distance(__first, __last).
///
/// !__pred(__first) allows us to guarantee that we don't
/// move-assign an element onto itself.
template<typename _ForwardIterator, typename _Pointer, typename _Predicate,
  typename _Distance>
  _ForwardIterator
  __stable_partition_adaptive(_ForwardIterator __first,
		_ForwardIterator __last,
		_Predicate __pred, _Distance __len,
		_Pointer __buffer,
		_Distance __buffer_size)
  {
    if (__len == 1)
return __first;

    if (__len <= __buffer_size)
{
 _ForwardIterator __result1 = __first;
 _Pointer __result2 = __buffer;

 // The precondition guarantees that !__pred(__first), so
 // move that element to the buffer before starting the loop.
 // This ensures that we only call __pred once per element.
 *__result2 = _GLIBCXX_MOVE(*__first)std::move(*__first);
 ++__result2;
 ++__first;
 for (; __first != __last; ++__first)
   if (__pred(__first))
     {
*__result1 = _GLIBCXX_MOVE(*__first)std::move(*__first);
++__result1;
     }
   else
     {
*__result2 = _GLIBCXX_MOVE(*__first)std::move(*__first);
++__result2;
     }

 _GLIBCXX_MOVE3(__buffer, __result2, __result1)std::move(__buffer, __result2, __result1);
 return __result1;
}

    _ForwardIterator __middle = __first;
    std::advance(__middle, __len / 2);
    _ForwardIterator __left_split =
std::__stable_partition_adaptive(__first, __middle, __pred,
			 __len / 2, __buffer,
			 __buffer_size);

    // Advance past true-predicate values to satisfy this
    // function's preconditions.
    _Distance __right_len = __len - __len / 2;
    _ForwardIterator __right_split =
std::__find_if_not_n(__middle, __right_len, __pred);

    if (__right_len)
__right_split =
 std::__stable_partition_adaptive(__right_split, __last, __pred,
			   __right_len,
			   __buffer, __buffer_size);

    std::rotate(__left_split, __middle, __right_split);
    std::advance(__left_split, std::distance(__middle, __right_split));
    return __left_split;
  }

template<typename _ForwardIterator, typename _Predicate>
  _ForwardIterator
  __stable_partition(_ForwardIterator __first, _ForwardIterator __last,
       _Predicate __pred)
  {
    __first = std::__find_if_not(__first, __last, __pred);

    if (__first == __last)
return __first;

    typedef typename iterator_traits<_ForwardIterator>::value_type
_ValueType;
    typedef typename iterator_traits<_ForwardIterator>::difference_type
_DistanceType;

    _Temporary_buffer<_ForwardIterator, _ValueType> __buf(__first, __last);
    return
std::__stable_partition_adaptive(__first, __last, __pred,
			 _DistanceType(__buf.requested_size()),
			 __buf.begin(),
			 _DistanceType(__buf.size()));
  }

/**
 *  @brief Move elements for which a predicate is true to the beginning
 *         of a sequence, preserving relative ordering.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __last    A forward iterator.
 *  @param  __pred    A predicate functor.
 *  @return  An iterator @p middle such that @p __pred(i) is true for each
 *  iterator @p i in the range @p [first,middle) and false for each @p i
 *  in the range @p [middle,last).
 *
 *  Performs the same function as @p partition() with the additional
 *  guarantee that the relative ordering of elements in each group is
 *  preserved, so any two elements @p x and @p y in the range
 *  @p [__first,__last) such that @p __pred(x)==__pred(y) will have the same
 *  relative ordering after calling @p stable_partition().
*/
template<typename _ForwardIterator, typename _Predicate>
  inline _ForwardIterator
  stable_partition(_ForwardIterator __first, _ForwardIterator __last,
     _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__stable_partition(__first, __last,
		     __gnu_cxx::__ops::__pred_iter(__pred));
  }

/// This is a helper function for the sort routines.
template<typename _RandomAccessIterator, typename _Compare>
  void
  __heap_select(_RandomAccessIterator __first,
  _RandomAccessIterator __middle,
  _RandomAccessIterator __last, _Compare __comp)
  {
    std::__make_heap(__first, __middle, __comp);
    for (_RandomAccessIterator __i = __middle; __i < __last; ++__i)
if (__comp(__i, __first))
 std::__pop_heap(__first, __middle, __i, __comp);
  }

// partial_sort

template<typename _InputIterator, typename _RandomAccessIterator,
  typename _Compare>
  _RandomAccessIterator
  __partial_sort_copy(_InputIterator __first, _InputIterator __last,
	_RandomAccessIterator __result_first,
	_RandomAccessIterator __result_last,
	_Compare __comp)
  {
    typedef typename iterator_traits<_InputIterator>::value_type
_InputValueType;
    typedef iterator_traits<_RandomAccessIterator> _RItTraits;
    typedef typename _RItTraits::difference_type _DistanceType;

    if (__result_first == __result_last)
return __result_last;
    _RandomAccessIterator __result_real_last = __result_first;
    while (__first != __last && __result_real_last != __result_last)
{
 *__result_real_last = *__first;
 ++__result_real_last;
 ++__first;
}
    
    std::__make_heap(__result_first, __result_real_last, __comp);
    while (__first != __last)
{
 if (__comp(__first, __result_first))
   std::__adjust_heap(__result_first, _DistanceType(0),
	       _DistanceType(__result_real_last
			     - __result_first),
	       _InputValueType(*__first), __comp);
 ++__first;
}
    std::__sort_heap(__result_first, __result_real_last, __comp);
    return __result_real_last;
  }

/**
 *  @brief Copy the smallest elements of a sequence.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __result_first   A random-access iterator.
 *  @param  __result_last    Another random-access iterator.
 *  @return   An iterator indicating the end of the resulting sequence.
 *
 *  Copies and sorts the smallest N values from the range @p [__first,__last)
 *  to the range beginning at @p __result_first, where the number of
 *  elements to be copied, @p N, is the smaller of @p (__last-__first) and
 *  @p (__result_last-__result_first).
 *  After the sort if @e i and @e j are iterators in the range
 *  @p [__result_first,__result_first+N) such that i precedes j then
 *  *j<*i is false.
 *  The value returned is @p __result_first+N.
*/
template<typename _InputIterator, typename _RandomAccessIterator>
  inline _RandomAccessIterator
  partial_sort_copy(_InputIterator __first, _InputIterator __last,
      _RandomAccessIterator __result_first,
      _RandomAccessIterator __result_last)
  {
1738#ifdef _GLIBCXX_CONCEPT_CHECKS
    typedef typename iterator_traits<_InputIterator>::value_type
_InputValueType;
    typedef typename iterator_traits<_RandomAccessIterator>::value_type
_OutputValueType;
1743#endif

    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_ConvertibleConcept<_InputValueType,
		  _OutputValueType>)
    __glibcxx_function_requires(_LessThanOpConcept<_InputValueType,
				     _OutputValueType>)
    __glibcxx_function_requires(_LessThanComparableConcept<_OutputValueType>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);
    __glibcxx_requires_valid_range(__result_first, __result_last);

    return std::__partial_sort_copy(__first, __last,
		      __result_first, __result_last,
		      __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Copy the smallest elements of a sequence using a predicate for
 *         comparison.
 *  @ingroup sorting_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    Another input iterator.
 *  @param  __result_first   A random-access iterator.
 *  @param  __result_last    Another random-access iterator.
 *  @param  __comp    A comparison functor.
 *  @return   An iterator indicating the end of the resulting sequence.
 *
 *  Copies and sorts the smallest N values from the range @p [__first,__last)
 *  to the range beginning at @p result_first, where the number of
 *  elements to be copied, @p N, is the smaller of @p (__last-__first) and
 *  @p (__result_last-__result_first).
 *  After the sort if @e i and @e j are iterators in the range
 *  @p [__result_first,__result_first+N) such that i precedes j then
 *  @p __comp(*j,*i) is false.
 *  The value returned is @p __result_first+N.
*/
template<typename _InputIterator, typename _RandomAccessIterator,
  typename _Compare>
  inline _RandomAccessIterator
  partial_sort_copy(_InputIterator __first, _InputIterator __last,
      _RandomAccessIterator __result_first,
      _RandomAccessIterator __result_last,
      _Compare __comp)
  {
1789#ifdef _GLIBCXX_CONCEPT_CHECKS
    typedef typename iterator_traits<_InputIterator>::value_type
_InputValueType;
    typedef typename iterator_traits<_RandomAccessIterator>::value_type
_OutputValueType;
1794#endif

    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
		  _RandomAccessIterator>)
    __glibcxx_function_requires(_ConvertibleConcept<_InputValueType,
		  _OutputValueType>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
		  _InputValueType, _OutputValueType>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
		  _OutputValueType, _OutputValueType>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
    __glibcxx_requires_valid_range(__result_first, __result_last);

    return std::__partial_sort_copy(__first, __last,
		      __result_first, __result_last,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

/// This is a helper function for the sort routine.
template<typename _RandomAccessIterator, typename _Compare>
  void
  __unguarded_linear_insert(_RandomAccessIterator __last,
	      _Compare __comp)
  {
    typename iterator_traits<_RandomAccessIterator>::value_type
__val = _GLIBCXX_MOVE(*__last)std::move(*__last);
    _RandomAccessIterator __next = __last;
    --__next;
    while (__comp(__val, __next))
{
 *__last = _GLIBCXX_MOVE(*__next)std::move(*__next);
 __last = __next;
 --__next;
}
    *__last = _GLIBCXX_MOVE(__val)std::move(__val);
  }

/// This is a helper function for the sort routine.
template<typename _RandomAccessIterator, typename _Compare>
  void
  __insertion_sort(_RandomAccessIterator __first,
     _RandomAccessIterator __last, _Compare __comp)
  {
    if (__first == __last) return;

    for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
{
 if (__comp(__i, __first))
   {
     typename iterator_traits<_RandomAccessIterator>::value_type
__val = _GLIBCXX_MOVE(*__i)std::move(*__i);
     _GLIBCXX_MOVE_BACKWARD3(__first, __i, __i + 1)std::move_backward(__first, __i, __i + 1);
     *__first = _GLIBCXX_MOVE(__val)std::move(__val);
   }
 else
   std::__unguarded_linear_insert(__i,
		__gnu_cxx::__ops::__val_comp_iter(__comp));
}
  }

/// This is a helper function for the sort routine.
template<typename _RandomAccessIterator, typename _Compare>
  inline void
  __unguarded_insertion_sort(_RandomAccessIterator __first,
	       _RandomAccessIterator __last, _Compare __comp)
  {
    for (_RandomAccessIterator __i = __first; __i != __last; ++__i)
std::__unguarded_linear_insert(__i,
		__gnu_cxx::__ops::__val_comp_iter(__comp));
  }

/**
 *  @doctodo
 *  This controls some aspect of the sort routines.
*/
enum { _S_threshold = 16 };

/// This is a helper function for the sort routine.
template<typename _RandomAccessIterator, typename _Compare>
  void
  __final_insertion_sort(_RandomAccessIterator __first,
	   _RandomAccessIterator __last, _Compare __comp)
  {
    if (__last - __first > int(_S_threshold))
{
 std::__insertion_sort(__first, __first + int(_S_threshold), __comp);
 std::__unguarded_insertion_sort(__first + int(_S_threshold), __last,
			  __comp);
}
    else
std::__insertion_sort(__first, __last, __comp);
  }

/// This is a helper function...
template<typename _RandomAccessIterator, typename _Compare>
  _RandomAccessIterator
  __unguarded_partition(_RandomAccessIterator __first,
	  _RandomAccessIterator __last,
	  _RandomAccessIterator __pivot, _Compare __comp)
  {
    while (true)
{
 while (__comp(__first, __pivot))
   ++__first;
 --__last;
 while (__comp(__pivot, __last))
   --__last;
 if (!(__first < __last))
   return __first;
 std::iter_swap(__first, __last);
 ++__first;
}
  }

/// This is a helper function...
template<typename _RandomAccessIterator, typename _Compare>
  inline _RandomAccessIterator
  __unguarded_partition_pivot(_RandomAccessIterator __first,
		_RandomAccessIterator __last, _Compare __comp)
  {
    _RandomAccessIterator __mid = __first + (__last - __first) / 2;
    std::__move_median_to_first(__first, __first + 1, __mid, __last - 1,
		  __comp);
    return std::__unguarded_partition(__first + 1, __last, __first, __comp);
  }

template<typename _RandomAccessIterator, typename _Compare>
  inline void
  __partial_sort(_RandomAccessIterator __first,
   _RandomAccessIterator __middle,
   _RandomAccessIterator __last,
   _Compare __comp)
  {
    std::__heap_select(__first, __middle, __last, __comp);
    std::__sort_heap(__first, __middle, __comp);
  }

/// This is a helper function for the sort routine.
template<typename _RandomAccessIterator, typename _Size, typename _Compare>
  void
  __introsort_loop(_RandomAccessIterator __first,
     _RandomAccessIterator __last,
     _Size __depth_limit, _Compare __comp)
  {
    while (__last - __first > int(_S_threshold))
{
 if (__depth_limit == 0)
   {
     std::__partial_sort(__first, __last, __last, __comp);
     return;
   }
 --__depth_limit;
 _RandomAccessIterator __cut =
   std::__unguarded_partition_pivot(__first, __last, __comp);
 std::__introsort_loop(__cut, __last, __depth_limit, __comp);
 __last = __cut;
}
  }

// sort

template<typename _RandomAccessIterator, typename _Compare>
  inline void
  __sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
  _Compare __comp)
  {
    if (__first != __last)
{
 std::__introsort_loop(__first, __last,
		std::__lg(__last - __first) * 2,
		__comp);
 std::__final_insertion_sort(__first, __last, __comp);
}
  }

template<typename _RandomAccessIterator, typename _Size, typename _Compare>
  void
  __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth,
  _RandomAccessIterator __last, _Size __depth_limit,
  _Compare __comp)
  {
    while (__last - __first > 3)
{
 if (__depth_limit == 0)
   {
     std::__heap_select(__first, __nth + 1, __last, __comp);
     // Place the nth largest element in its final position.
     std::iter_swap(__first, __nth);
     return;
   }
 --__depth_limit;
 _RandomAccessIterator __cut =
   std::__unguarded_partition_pivot(__first, __last, __comp);
 if (__cut <= __nth)
   __first = __cut;
 else
   __last = __cut;
}
    std::__insertion_sort(__first, __last, __comp);
  }

// nth_element

// lower_bound moved to stl_algobase.h

/**
 *  @brief Finds the first position in which @p __val could be inserted
 *         without changing the ordering.
 *  @ingroup binary_search_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @param  __comp    A functor to use for comparisons.
 *  @return An iterator pointing to the first element <em>not less
 *           than</em> @p __val, or end() if every element is less
 *           than @p __val.
 *  @ingroup binary_search_algorithms
 *
 *  The comparison function should have the same effects on ordering as
 *  the function used for the initial sort.
*/
template<typename _ForwardIterator, typename _Tp, typename _Compare>
  inline _ForwardIterator
  lower_bound(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __val, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_requires_partitioned_lower_pred(__first, __last,
				__val, __comp);

    return std::__lower_bound(__first, __last, __val,
		__gnu_cxx::__ops::__iter_comp_val(__comp));
  }

template<typename _ForwardIterator, typename _Tp, typename _Compare>
  _ForwardIterator
  __upper_bound(_ForwardIterator __first, _ForwardIterator __last,
  const _Tp& __val, _Compare __comp)
  {
    typedef typename iterator_traits<_ForwardIterator>::difference_type
_DistanceType;

    _DistanceType __len = std::distance(__first, __last);

    while (__len > 0)
{
 _DistanceType __half = __len >> 1;
 _ForwardIterator __middle = __first;
 std::advance(__middle, __half);
 if (__comp(__val, __middle))
   __len = __half;
 else
   {
     __first = __middle;
     ++__first;
     __len = __len - __half - 1;
   }
}
    return __first;
  }

/**
 *  @brief Finds the last position in which @p __val could be inserted
 *         without changing the ordering.
 *  @ingroup binary_search_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @return  An iterator pointing to the first element greater than @p __val,
 *           or end() if no elements are greater than @p __val.
 *  @ingroup binary_search_algorithms
*/
template<typename _ForwardIterator, typename _Tp>
  inline _ForwardIterator
  upper_bound(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __val)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanOpConcept<
_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_partitioned_upper(__first, __last, __val);

    return std::__upper_bound(__first, __last, __val,
		__gnu_cxx::__ops::__val_less_iter());
  }

/**
 *  @brief Finds the last position in which @p __val could be inserted
 *         without changing the ordering.
 *  @ingroup binary_search_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @param  __comp    A functor to use for comparisons.
 *  @return  An iterator pointing to the first element greater than @p __val,
 *           or end() if no elements are greater than @p __val.
 *  @ingroup binary_search_algorithms
 *
 *  The comparison function should have the same effects on ordering as
 *  the function used for the initial sort.
*/
template<typename _ForwardIterator, typename _Tp, typename _Compare>
  inline _ForwardIterator
  upper_bound(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __val, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_partitioned_upper_pred(__first, __last,
				__val, __comp);

    return std::__upper_bound(__first, __last, __val,
		__gnu_cxx::__ops::__val_comp_iter(__comp));
  }

template<typename _ForwardIterator, typename _Tp,
  typename _CompareItTp, typename _CompareTpIt>
  pair<_ForwardIterator, _ForwardIterator>
  __equal_range(_ForwardIterator __first, _ForwardIterator __last,
  const _Tp& __val,
  _CompareItTp __comp_it_val, _CompareTpIt __comp_val_it)
  {
    typedef typename iterator_traits<_ForwardIterator>::difference_type
_DistanceType;

    _DistanceType __len = std::distance(__first, __last);

    while (__len > 0)
{
 _DistanceType __half = __len >> 1;
 _ForwardIterator __middle = __first;
 std::advance(__middle, __half);
 if (__comp_it_val(__middle, __val))
   {
     __first = __middle;
     ++__first;
     __len = __len - __half - 1;
   }
 else if (__comp_val_it(__val, __middle))
   __len = __half;
 else
   {
     _ForwardIterator __left
= std::__lower_bound(__first, __middle, __val, __comp_it_val);
     std::advance(__first, __len);
     _ForwardIterator __right
= std::__upper_bound(++__middle, __first, __val, __comp_val_it);
     return pair<_ForwardIterator, _ForwardIterator>(__left, __right);
   }
}
    return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
  }

/**
 *  @brief Finds the largest subrange in which @p __val could be inserted
 *         at any place in it without changing the ordering.
 *  @ingroup binary_search_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @return  An pair of iterators defining the subrange.
 *  @ingroup binary_search_algorithms
 *
 *  This is equivalent to
 *  @code
 *    std::make_pair(lower_bound(__first, __last, __val),
 *                   upper_bound(__first, __last, __val))
 *  @endcode
 *  but does not actually call those functions.
*/
template<typename _ForwardIterator, typename _Tp>
  inline pair<_ForwardIterator, _ForwardIterator>
  equal_range(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __val)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanOpConcept<
typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_function_requires(_LessThanOpConcept<
_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_partitioned_lower(__first, __last, __val);
    __glibcxx_requires_partitioned_upper(__first, __last, __val);

    return std::__equal_range(__first, __last, __val,
		__gnu_cxx::__ops::__iter_less_val(),
		__gnu_cxx::__ops::__val_less_iter());
  }

/**
 *  @brief Finds the largest subrange in which @p __val could be inserted
 *         at any place in it without changing the ordering.
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @param  __comp    A functor to use for comparisons.
 *  @return  An pair of iterators defining the subrange.
 *  @ingroup binary_search_algorithms
 *
 *  This is equivalent to
 *  @code
 *    std::make_pair(lower_bound(__first, __last, __val, __comp),
 *                   upper_bound(__first, __last, __val, __comp))
 *  @endcode
 *  but does not actually call those functions.
*/
template<typename _ForwardIterator, typename _Tp, typename _Compare>
  inline pair<_ForwardIterator, _ForwardIterator>
  equal_range(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __val, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_partitioned_lower_pred(__first, __last,
				__val, __comp);
    __glibcxx_requires_partitioned_upper_pred(__first, __last,
				__val, __comp);

    return std::__equal_range(__first, __last, __val,
		__gnu_cxx::__ops::__iter_comp_val(__comp),
		__gnu_cxx::__ops::__val_comp_iter(__comp));
  }

/**
 *  @brief Determines whether an element exists in a range.
 *  @ingroup binary_search_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @return True if @p __val (or its equivalent) is in [@p
 *  __first,@p __last ].
 *
 *  Note that this does not actually return an iterator to @p __val.  For
 *  that, use std::find or a container's specialized find member functions.
*/
template<typename _ForwardIterator, typename _Tp>
  bool
  binary_search(_ForwardIterator __first, _ForwardIterator __last,
  const _Tp& __val)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanOpConcept<
_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_partitioned_lower(__first, __last, __val);
    __glibcxx_requires_partitioned_upper(__first, __last, __val);

    _ForwardIterator __i
= std::__lower_bound(__first, __last, __val,
	     __gnu_cxx::__ops::__iter_less_val());
    return __i != __last && !(__val < *__i);
  }

/**
 *  @brief Determines whether an element exists in a range.
 *  @ingroup binary_search_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __val     The search term.
 *  @param  __comp    A functor to use for comparisons.
 *  @return  True if @p __val (or its equivalent) is in @p [__first,__last].
 *
 *  Note that this does not actually return an iterator to @p __val.  For
 *  that, use std::find or a container's specialized find member functions.
 *
 *  The comparison function should have the same effects on ordering as
 *  the function used for the initial sort.
*/
template<typename _ForwardIterator, typename _Tp, typename _Compare>
  bool
  binary_search(_ForwardIterator __first, _ForwardIterator __last,
  const _Tp& __val, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_partitioned_lower_pred(__first, __last,
				__val, __comp);
    __glibcxx_requires_partitioned_upper_pred(__first, __last,
				__val, __comp);

    _ForwardIterator __i
= std::__lower_bound(__first, __last, __val,
	     __gnu_cxx::__ops::__iter_comp_val(__comp));
    return __i != __last && !bool(__comp(__val, *__i));
  }

// merge

/// This is a helper function for the __merge_adaptive routines.
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  void
  __move_merge_adaptive(_InputIterator1 __first1, _InputIterator1 __last1,
	  _InputIterator2 __first2, _InputIterator2 __last2,
	  _OutputIterator __result, _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
{
 if (__comp(__first2, __first1))
   {
     *__result = _GLIBCXX_MOVE(*__first2)std::move(*__first2);
     ++__first2;
   }
 else
   {
     *__result = _GLIBCXX_MOVE(*__first1)std::move(*__first1);
     ++__first1;
   }
 ++__result;
}
    if (__first1 != __last1)
_GLIBCXX_MOVE3(__first1, __last1, __result)std::move(__first1, __last1, __result);
  }

/// This is a helper function for the __merge_adaptive routines.
template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
  typename _BidirectionalIterator3, typename _Compare>
  void
  __move_merge_adaptive_backward(_BidirectionalIterator1 __first1,
		   _BidirectionalIterator1 __last1,
		   _BidirectionalIterator2 __first2,
		   _BidirectionalIterator2 __last2,
		   _BidirectionalIterator3 __result,
		   _Compare __comp)
  {
    if (__first1 == __last1)
{
 _GLIBCXX_MOVE_BACKWARD3(__first2, __last2, __result)std::move_backward(__first2, __last2, __result);
 return;
}
    else if (__first2 == __last2)
return;

    --__last1;
    --__last2;
    while (true)
{
 if (__comp(__last2, __last1))
   {
     *--__result = _GLIBCXX_MOVE(*__last1)std::move(*__last1);
     if (__first1 == __last1)
{
  _GLIBCXX_MOVE_BACKWARD3(__first2, ++__last2, __result)std::move_backward(__first2, ++__last2, __result);
  return;
}
     --__last1;
   }
 else
   {
     *--__result = _GLIBCXX_MOVE(*__last2)std::move(*__last2);
     if (__first2 == __last2)
return;
     --__last2;
   }
}
  }

/// This is a helper function for the merge routines.
template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
  typename _Distance>
  _BidirectionalIterator1
  __rotate_adaptive(_BidirectionalIterator1 __first,
      _BidirectionalIterator1 __middle,
      _BidirectionalIterator1 __last,
      _Distance __len1, _Distance __len2,
      _BidirectionalIterator2 __buffer,
      _Distance __buffer_size)
  {
    _BidirectionalIterator2 __buffer_end;
    if (__len1 > __len2 && __len2 <= __buffer_size)
{
 if (__len2)
   {
     __buffer_end = _GLIBCXX_MOVE3(__middle, __last, __buffer)std::move(__middle, __last, __buffer);
     _GLIBCXX_MOVE_BACKWARD3(__first, __middle, __last)std::move_backward(__first, __middle, __last);
     return _GLIBCXX_MOVE3(__buffer, __buffer_end, __first)std::move(__buffer, __buffer_end, __first);
   }
 else
   return __first;
}
    else if (__len1 <= __buffer_size)
{
 if (__len1)
   {
     __buffer_end = _GLIBCXX_MOVE3(__first, __middle, __buffer)std::move(__first, __middle, __buffer);
     _GLIBCXX_MOVE3(__middle, __last, __first)std::move(__middle, __last, __first);
     return _GLIBCXX_MOVE_BACKWARD3(__buffer, __buffer_end, __last)std::move_backward(__buffer, __buffer_end, __last);
   }
 else
   return __last;
}
    else
{
 std::rotate(__first, __middle, __last);
 std::advance(__first, std::distance(__middle, __last));
 return __first;
}
  }

/// This is a helper function for the merge routines.
template<typename _BidirectionalIterator, typename _Distance, 
  typename _Pointer, typename _Compare>
  void
  __merge_adaptive(_BidirectionalIterator __first,
     _BidirectionalIterator __middle,
     _BidirectionalIterator __last,
     _Distance __len1, _Distance __len2,
     _Pointer __buffer, _Distance __buffer_size,
     _Compare __comp)
  {
    if (__len1 <= __len2 && __len1 <= __buffer_size)
{
 _Pointer __buffer_end = _GLIBCXX_MOVE3(__first, __middle, __buffer)std::move(__first, __middle, __buffer);
 std::__move_merge_adaptive(__buffer, __buffer_end, __middle, __last,
		     __first, __comp);
}
    else if (__len2 <= __buffer_size)
{
 _Pointer __buffer_end = _GLIBCXX_MOVE3(__middle, __last, __buffer)std::move(__middle, __last, __buffer);
 std::__move_merge_adaptive_backward(__first, __middle, __buffer,
			      __buffer_end, __last, __comp);
}
    else
{
 _BidirectionalIterator __first_cut = __first;
 _BidirectionalIterator __second_cut = __middle;
 _Distance __len11 = 0;
 _Distance __len22 = 0;
 if (__len1 > __len2)
   {
     __len11 = __len1 / 2;
     std::advance(__first_cut, __len11);
     __second_cut
= std::__lower_bound(__middle, __last, *__first_cut,
		     __gnu_cxx::__ops::__iter_comp_val(__comp));
     __len22 = std::distance(__middle, __second_cut);
   }
 else
   {
     __len22 = __len2 / 2;
     std::advance(__second_cut, __len22);
     __first_cut
= std::__upper_bound(__first, __middle, *__second_cut,
		     __gnu_cxx::__ops::__val_comp_iter(__comp));
     __len11 = std::distance(__first, __first_cut);
   }

 _BidirectionalIterator __new_middle
   = std::__rotate_adaptive(__first_cut, __middle, __second_cut,
		     __len1 - __len11, __len22, __buffer,
		     __buffer_size);
 std::__merge_adaptive(__first, __first_cut, __new_middle, __len11,
		__len22, __buffer, __buffer_size, __comp);
 std::__merge_adaptive(__new_middle, __second_cut, __last,
		__len1 - __len11,
		__len2 - __len22, __buffer,
		__buffer_size, __comp);
}
  }

/// This is a helper function for the merge routines.
template<typename _BidirectionalIterator, typename _Distance,
  typename _Compare>
  void
  __merge_without_buffer(_BidirectionalIterator __first,
	   _BidirectionalIterator __middle,
	   _BidirectionalIterator __last,
	   _Distance __len1, _Distance __len2,
	   _Compare __comp)
  {
    if (__len1 == 0 || __len2 == 0)
return;

    if (__len1 + __len2 == 2)
{
 if (__comp(__middle, __first))
   std::iter_swap(__first, __middle);
 return;
}

    _BidirectionalIterator __first_cut = __first;
    _BidirectionalIterator __second_cut = __middle;
    _Distance __len11 = 0;
    _Distance __len22 = 0;
    if (__len1 > __len2)
{
 __len11 = __len1 / 2;
 std::advance(__first_cut, __len11);
 __second_cut
   = std::__lower_bound(__middle, __last, *__first_cut,
		 __gnu_cxx::__ops::__iter_comp_val(__comp));
 __len22 = std::distance(__middle, __second_cut);
}
    else
{
 __len22 = __len2 / 2;
 std::advance(__second_cut, __len22);
 __first_cut
   = std::__upper_bound(__first, __middle, *__second_cut,
		 __gnu_cxx::__ops::__val_comp_iter(__comp));
 __len11 = std::distance(__first, __first_cut);
}

    std::rotate(__first_cut, __middle, __second_cut);
    _BidirectionalIterator __new_middle = __first_cut;
    std::advance(__new_middle, std::distance(__middle, __second_cut));
    std::__merge_without_buffer(__first, __first_cut, __new_middle,
		  __len11, __len22, __comp);
    std::__merge_without_buffer(__new_middle, __second_cut, __last,
		  __len1 - __len11, __len2 - __len22, __comp);
  }

template<typename _BidirectionalIterator, typename _Compare>
  void
  __inplace_merge(_BidirectionalIterator __first,
    _BidirectionalIterator __middle,
    _BidirectionalIterator __last,
    _Compare __comp)
  {
    typedef typename iterator_traits<_BidirectionalIterator>::value_type
 _ValueType;
    typedef typename iterator_traits<_BidirectionalIterator>::difference_type
 _DistanceType;

    if (__first == __middle || __middle == __last)
return;

    const _DistanceType __len1 = std::distance(__first, __middle);
    const _DistanceType __len2 = std::distance(__middle, __last);

    typedef _Temporary_buffer<_BidirectionalIterator, _ValueType> _TmpBuf;
    _TmpBuf __buf(__first, __last);

    if (__buf.begin() == 0)
std::__merge_without_buffer
 (__first, __middle, __last, __len1, __len2, __comp);
    else
std::__merge_adaptive
 (__first, __middle, __last, __len1, __len2, __buf.begin(),
  _DistanceType(__buf.size()), __comp);
  }

/**
 *  @brief Merges two sorted ranges in place.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __middle  Another iterator.
 *  @param  __last    Another iterator.
 *  @return  Nothing.
 *
 *  Merges two sorted and consecutive ranges, [__first,__middle) and
 *  [__middle,__last), and puts the result in [__first,__last).  The
 *  output will be sorted.  The sort is @e stable, that is, for
 *  equivalent elements in the two ranges, elements from the first
 *  range will always come before elements from the second.
 *
 *  If enough additional memory is available, this takes (__last-__first)-1
 *  comparisons.  Otherwise an NlogN algorithm is used, where N is
 *  distance(__first,__last).
*/
template<typename _BidirectionalIterator>
  inline void
  inplace_merge(_BidirectionalIterator __first,
  _BidirectionalIterator __middle,
  _BidirectionalIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
   _BidirectionalIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_sorted(__first, __middle);
    __glibcxx_requires_sorted(__middle, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    std::__inplace_merge(__first, __middle, __last,
	   __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Merges two sorted ranges in place.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __middle  Another iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A functor to use for comparisons.
 *  @return  Nothing.
 *
 *  Merges two sorted and consecutive ranges, [__first,__middle) and
 *  [middle,last), and puts the result in [__first,__last).  The output will
 *  be sorted.  The sort is @e stable, that is, for equivalent
 *  elements in the two ranges, elements from the first range will always
 *  come before elements from the second.
 *
 *  If enough additional memory is available, this takes (__last-__first)-1
 *  comparisons.  Otherwise an NlogN algorithm is used, where N is
 *  distance(__first,__last).
 *
 *  The comparison function should have the same effects on ordering as
 *  the function used for the initial sort.
*/
template<typename _BidirectionalIterator, typename _Compare>
  inline void
  inplace_merge(_BidirectionalIterator __first,
  _BidirectionalIterator __middle,
  _BidirectionalIterator __last,
  _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
   _BidirectionalIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_BidirectionalIterator>::value_type,
   typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_sorted_pred(__first, __middle, __comp);
    __glibcxx_requires_sorted_pred(__middle, __last, __comp);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    std::__inplace_merge(__first, __middle, __last,
	   __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }


/// This is a helper function for the __merge_sort_loop routines.
template<typename _InputIterator, typename _OutputIterator,
  typename _Compare>
  _OutputIterator
  __move_merge(_InputIterator __first1, _InputIterator __last1,
 _InputIterator __first2, _InputIterator __last2,
 _OutputIterator __result, _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
{
 if (__comp(__first2, __first1))
   {
     *__result = _GLIBCXX_MOVE(*__first2)std::move(*__first2);
     ++__first2;
   }
 else
   {
     *__result = _GLIBCXX_MOVE(*__first1)std::move(*__first1);
     ++__first1;
   }
 ++__result;
}
    return _GLIBCXX_MOVE3(__first2, __last2,std::move(__first2, __last2, std::move(__first1, __last1, __result
))
	    _GLIBCXX_MOVE3(__first1, __last1,std::move(__first2, __last2, std::move(__first1, __last1, __result
))
			   __result))std::move(__first2, __last2, std::move(__first1, __last1, __result
));
  }

template<typename _RandomAccessIterator1, typename _RandomAccessIterator2,
  typename _Distance, typename _Compare>
  void
  __merge_sort_loop(_RandomAccessIterator1 __first,
      _RandomAccessIterator1 __last,
      _RandomAccessIterator2 __result, _Distance __step_size,
      _Compare __comp)
  {
    const _Distance __two_step = 2 * __step_size;

    while (__last - __first >= __two_step)
{
 __result = std::__move_merge(__first, __first + __step_size,
		       __first + __step_size,
		       __first + __two_step,
		       __result, __comp);
 __first += __two_step;
}
    __step_size = std::min(_Distance(__last - __first), __step_size);

    std::__move_merge(__first, __first + __step_size,
	__first + __step_size, __last, __result, __comp);
  }

template<typename _RandomAccessIterator, typename _Distance,
  typename _Compare>
  void
  __chunk_insertion_sort(_RandomAccessIterator __first,
	   _RandomAccessIterator __last,
	   _Distance __chunk_size, _Compare __comp)
  {
    while (__last - __first >= __chunk_size)
{
 std::__insertion_sort(__first, __first + __chunk_size, __comp);
 __first += __chunk_size;
}
    std::__insertion_sort(__first, __last, __comp);
  }

enum { _S_chunk_size = 7 };

template<typename _RandomAccessIterator, typename _Pointer, typename _Compare>
  void
  __merge_sort_with_buffer(_RandomAccessIterator __first,
	     _RandomAccessIterator __last,
	     _Pointer __buffer, _Compare __comp)
  {
    typedef typename iterator_traits<_RandomAccessIterator>::difference_type
_Distance;

    const _Distance __len = __last - __first;
    const _Pointer __buffer_last = __buffer + __len;

    _Distance __step_size = _S_chunk_size;
    std::__chunk_insertion_sort(__first, __last, __step_size, __comp);

    while (__step_size < __len)
{
 std::__merge_sort_loop(__first, __last, __buffer,
		 __step_size, __comp);
 __step_size *= 2;
 std::__merge_sort_loop(__buffer, __buffer_last, __first,
		 __step_size, __comp);
 __step_size *= 2;
}
  }

template<typename _RandomAccessIterator, typename _Pointer,
  typename _Distance, typename _Compare>
  void
  __stable_sort_adaptive(_RandomAccessIterator __first,
	   _RandomAccessIterator __last,
	   _Pointer __buffer, _Distance __buffer_size,
	   _Compare __comp)
  {
    const _Distance __len = (__last - __first + 1) / 2;
    const _RandomAccessIterator __middle = __first + __len;
    if (__len > __buffer_size)
{
 std::__stable_sort_adaptive(__first, __middle, __buffer,
		      __buffer_size, __comp);
 std::__stable_sort_adaptive(__middle, __last, __buffer,
		      __buffer_size, __comp);
}
    else
{
 std::__merge_sort_with_buffer(__first, __middle, __buffer, __comp);
 std::__merge_sort_with_buffer(__middle, __last, __buffer, __comp);
}
    std::__merge_adaptive(__first, __middle, __last,
	    _Distance(__middle - __first),
	    _Distance(__last - __middle),
	    __buffer, __buffer_size,
	    __comp);
  }

/// This is a helper function for the stable sorting routines.
template<typename _RandomAccessIterator, typename _Compare>
  void
  __inplace_stable_sort(_RandomAccessIterator __first,
	  _RandomAccessIterator __last, _Compare __comp)
  {
    if (__last - __first < 15)
{
 std::__insertion_sort(__first, __last, __comp);
 return;
}
    _RandomAccessIterator __middle = __first + (__last - __first) / 2;
    std::__inplace_stable_sort(__first, __middle, __comp);
    std::__inplace_stable_sort(__middle, __last, __comp);
    std::__merge_without_buffer(__first, __middle, __last,
		  __middle - __first,
		  __last - __middle,
		  __comp);
  }

// stable_sort

// Set algorithms: includes, set_union, set_intersection, set_difference,
// set_symmetric_difference.  All of these algorithms have the precondition
// that their input ranges are sorted and the postcondition that their output
// ranges are sorted.

template<typename _InputIterator1, typename _InputIterator2,
  typename _Compare>
  bool
  __includes(_InputIterator1 __first1, _InputIterator1 __last1,
      _InputIterator2 __first2, _InputIterator2 __last2,
      _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
if (__comp(__first2, __first1))
 return false;
else if (__comp(__first1, __first2))
 ++__first1;
else
 {
   ++__first1;
   ++__first2;
 }

    return __first2 == __last2;
  }

/**
 *  @brief Determines whether all elements of a sequence exists in a range.
 *  @param  __first1  Start of search range.
 *  @param  __last1   End of search range.
 *  @param  __first2  Start of sequence
 *  @param  __last2   End of sequence.
 *  @return  True if each element in [__first2,__last2) is contained in order
 *  within [__first1,__last1).  False otherwise.
 *  @ingroup set_algorithms
 *
 *  This operation expects both [__first1,__last1) and
 *  [__first2,__last2) to be sorted.  Searches for the presence of
 *  each element in [__first2,__last2) within [__first1,__last1).
 *  The iterators over each range only move forward, so this is a
 *  linear algorithm.  If an element in [__first2,__last2) is not
 *  found before the search iterator reaches @p __last2, false is
 *  returned.
*/
template<typename _InputIterator1, typename _InputIterator2>
  inline bool
  includes(_InputIterator1 __first1, _InputIterator1 __last1,
    _InputIterator2 __first2, _InputIterator2 __last2)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set(__first1, __last1, __first2);
    __glibcxx_requires_sorted_set(__first2, __last2, __first1);
    __glibcxx_requires_irreflexive2(__first1, __last1);
    __glibcxx_requires_irreflexive2(__first2, __last2);

    return std::__includes(__first1, __last1, __first2, __last2,
	     __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Determines whether all elements of a sequence exists in a range
 *  using comparison.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of search range.
 *  @param  __last1   End of search range.
 *  @param  __first2  Start of sequence
 *  @param  __last2   End of sequence.
 *  @param  __comp    Comparison function to use.
 *  @return True if each element in [__first2,__last2) is contained
 *  in order within [__first1,__last1) according to comp.  False
 *  otherwise.  @ingroup set_algorithms
 *
 *  This operation expects both [__first1,__last1) and
 *  [__first2,__last2) to be sorted.  Searches for the presence of
 *  each element in [__first2,__last2) within [__first1,__last1),
 *  using comp to decide.  The iterators over each range only move
 *  forward, so this is a linear algorithm.  If an element in
 *  [__first2,__last2) is not found before the search iterator
 *  reaches @p __last2, false is returned.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _Compare>
  inline bool
  includes(_InputIterator1 __first1, _InputIterator1 __last1,
    _InputIterator2 __first2, _InputIterator2 __last2,
    _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
    __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);

    return std::__includes(__first1, __last1, __first2, __last2,
	     __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

// nth_element
// merge
// set_difference
// set_intersection
// set_union
// stable_sort
// set_symmetric_difference
// min_element
// max_element

template<typename _BidirectionalIterator, typename _Compare>
  bool
  __next_permutation(_BidirectionalIterator __first,
       _BidirectionalIterator __last, _Compare __comp)
  {
    if (__first == __last)
return false;
    _BidirectionalIterator __i = __first;
    ++__i;
    if (__i == __last)
return false;
    __i = __last;
    --__i;

    for(;;)
{
 _BidirectionalIterator __ii = __i;
 --__i;
 if (__comp(__i, __ii))
   {
     _BidirectionalIterator __j = __last;
     while (!__comp(__i, --__j))
{}
     std::iter_swap(__i, __j);
     std::__reverse(__ii, __last,
	     std::__iterator_category(__first));
     return true;
   }
 if (__i == __first)
   {
     std::__reverse(__first, __last,
	     std::__iterator_category(__first));
     return false;
   }
}
  }

/**
 *  @brief  Permute range into the next @e dictionary ordering.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @return  False if wrapped to first permutation, true otherwise.
 *
 *  Treats all permutations of the range as a set of @e dictionary sorted
 *  sequences.  Permutes the current sequence into the next one of this set.
 *  Returns true if there are more sequences to generate.  If the sequence
 *  is the largest of the set, the smallest is generated and false returned.
*/
template<typename _BidirectionalIterator>
  inline bool
  next_permutation(_BidirectionalIterator __first,
     _BidirectionalIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    return std::__next_permutation
(__first, __last, __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Permute range into the next @e dictionary ordering using
 *          comparison functor.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @param  __comp   A comparison functor.
 *  @return  False if wrapped to first permutation, true otherwise.
 *
 *  Treats all permutations of the range [__first,__last) as a set of
 *  @e dictionary sorted sequences ordered by @p __comp.  Permutes the current
 *  sequence into the next one of this set.  Returns true if there are more
 *  sequences to generate.  If the sequence is the largest of the set, the
 *  smallest is generated and false returned.
*/
template<typename _BidirectionalIterator, typename _Compare>
  inline bool
  next_permutation(_BidirectionalIterator __first,
     _BidirectionalIterator __last, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_BidirectionalIterator>::value_type,
   typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    return std::__next_permutation
(__first, __last, __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _BidirectionalIterator, typename _Compare>
  bool
  __prev_permutation(_BidirectionalIterator __first,
       _BidirectionalIterator __last, _Compare __comp)
  {
    if (__first == __last)
return false;
    _BidirectionalIterator __i = __first;
    ++__i;
    if (__i == __last)
return false;
    __i = __last;
    --__i;

    for(;;)
{
 _BidirectionalIterator __ii = __i;
 --__i;
 if (__comp(__ii, __i))
   {
     _BidirectionalIterator __j = __last;
     while (!__comp(--__j, __i))
{}
     std::iter_swap(__i, __j);
     std::__reverse(__ii, __last,
	     std::__iterator_category(__first));
     return true;
   }
 if (__i == __first)
   {
     std::__reverse(__first, __last,
	     std::__iterator_category(__first));
     return false;
   }
}
  }

/**
 *  @brief  Permute range into the previous @e dictionary ordering.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @return  False if wrapped to last permutation, true otherwise.
 *
 *  Treats all permutations of the range as a set of @e dictionary sorted
 *  sequences.  Permutes the current sequence into the previous one of this
 *  set.  Returns true if there are more sequences to generate.  If the
 *  sequence is the smallest of the set, the largest is generated and false
 *  returned.
*/
template<typename _BidirectionalIterator>
  inline bool
  prev_permutation(_BidirectionalIterator __first,
     _BidirectionalIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    return std::__prev_permutation(__first, __last,
		     __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Permute range into the previous @e dictionary ordering using
 *          comparison functor.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @param  __comp   A comparison functor.
 *  @return  False if wrapped to last permutation, true otherwise.
 *
 *  Treats all permutations of the range [__first,__last) as a set of
 *  @e dictionary sorted sequences ordered by @p __comp.  Permutes the current
 *  sequence into the previous one of this set.  Returns true if there are
 *  more sequences to generate.  If the sequence is the smallest of the set,
 *  the largest is generated and false returned.
*/
template<typename _BidirectionalIterator, typename _Compare>
  inline bool
  prev_permutation(_BidirectionalIterator __first,
     _BidirectionalIterator __last, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_BidirectionalIteratorConcept<
		  _BidirectionalIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_BidirectionalIterator>::value_type,
   typename iterator_traits<_BidirectionalIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    return std::__prev_permutation(__first, __last,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

// replace
// replace_if

template<typename _InputIterator, typename _OutputIterator,
  typename _Predicate, typename _Tp>
  _OutputIterator
  __replace_copy_if(_InputIterator __first, _InputIterator __last,
      _OutputIterator __result,
      _Predicate __pred, const _Tp& __new_value)
  {
    for (; __first != __last; ++__first, (void)++__result)
if (__pred(__first))
 *__result = __new_value;
else
 *__result = *__first;
    return __result;
  }

/**
 *  @brief Copy a sequence, replacing each element of one value with another
 *         value.
 *  @param  __first      An input iterator.
 *  @param  __last       An input iterator.
 *  @param  __result     An output iterator.
 *  @param  __old_value  The value to be replaced.
 *  @param  __new_value  The replacement value.
 *  @return   The end of the output sequence, @p result+(last-first).
 *
 *  Copies each element in the input range @p [__first,__last) to the
 *  output range @p [__result,__result+(__last-__first)) replacing elements
 *  equal to @p __old_value with @p __new_value.
*/
template<typename _InputIterator, typename _OutputIterator, typename _Tp>
  inline _OutputIterator
  replace_copy(_InputIterator __first, _InputIterator __last,
 _OutputIterator __result,
 const _Tp& __old_value, const _Tp& __new_value)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_InputIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__replace_copy_if(__first, __last, __result,
	__gnu_cxx::__ops::__iter_equals_val(__old_value),
			      __new_value);
  }

/**
 *  @brief Copy a sequence, replacing each value for which a predicate
 *         returns true with another value.
 *  @ingroup mutating_algorithms
 *  @param  __first      An input iterator.
 *  @param  __last       An input iterator.
 *  @param  __result     An output iterator.
 *  @param  __pred       A predicate.
 *  @param  __new_value  The replacement value.
 *  @return   The end of the output sequence, @p __result+(__last-__first).
 *
 *  Copies each element in the range @p [__first,__last) to the range
 *  @p [__result,__result+(__last-__first)) replacing elements for which
 *  @p __pred returns true with @p __new_value.
*/
template<typename _InputIterator, typename _OutputIterator,
  typename _Predicate, typename _Tp>
  inline _OutputIterator
  replace_copy_if(_InputIterator __first, _InputIterator __last,
    _OutputIterator __result,
    _Predicate __pred, const _Tp& __new_value)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__replace_copy_if(__first, __last, __result,
		__gnu_cxx::__ops::__pred_iter(__pred),
			      __new_value);
  }

template<typename _InputIterator, typename _Predicate>
  typename iterator_traits<_InputIterator>::difference_type
  __count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
  {
    typename iterator_traits<_InputIterator>::difference_type __n = 0;
    for (; __first != __last; ++__first)
if (__pred(__first))
 ++__n;
    return __n;
  }

3196#if __cplusplus201402L >= 201103L
/**
 *  @brief  Determines whether the elements of a sequence are sorted.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @return  True if the elements are sorted, false otherwise.
*/
template<typename _ForwardIterator>
  inline bool
  is_sorted(_ForwardIterator __first, _ForwardIterator __last)
  { return std::is_sorted_until(__first, __last) == __last; }

/**
 *  @brief  Determines whether the elements of a sequence are sorted
 *          according to a comparison functor.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A comparison functor.
 *  @return  True if the elements are sorted, false otherwise.
*/
template<typename _ForwardIterator, typename _Compare>
  inline bool
  is_sorted(_ForwardIterator __first, _ForwardIterator __last,
     _Compare __comp)
  { return std::is_sorted_until(__first, __last, __comp) == __last; }

template<typename _ForwardIterator, typename _Compare>
  _ForwardIterator
  __is_sorted_until(_ForwardIterator __first, _ForwardIterator __last,
      _Compare __comp)
  {
    if (__first == __last)
return __last;

    _ForwardIterator __next = __first;
    for (++__next; __next != __last; __first = __next, (void)++__next)
if (__comp(__next, __first))
 return __next;
    return __next;
  }

/**
 *  @brief  Determines the end of a sorted sequence.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @return  An iterator pointing to the last iterator i in [__first, __last)
 *           for which the range [__first, i) is sorted.
*/
template<typename _ForwardIterator>
  inline _ForwardIterator
  is_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    return std::__is_sorted_until(__first, __last,
		    __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Determines the end of a sorted sequence using comparison functor.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A comparison functor.
 *  @return  An iterator pointing to the last iterator i in [__first, __last)
 *           for which the range [__first, i) is sorted.
*/
template<typename _ForwardIterator, typename _Compare>
  inline _ForwardIterator
  is_sorted_until(_ForwardIterator __first, _ForwardIterator __last,
    _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_ForwardIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    return std::__is_sorted_until(__first, __last,
		    __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

/**
 *  @brief  Determines min and max at once as an ordered pair.
 *  @ingroup sorting_algorithms
 *  @param  __a  A thing of arbitrary type.
 *  @param  __b  Another thing of arbitrary type.
 *  @return A pair(__b, __a) if __b is smaller than __a, pair(__a,
 *  __b) otherwise.
*/
template<typename _Tp>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline pair<const _Tp&, const _Tp&>
  minmax(const _Tp& __a, const _Tp& __b)
  {
    // concept requirements
    __glibcxx_function_requires(_LessThanComparableConcept<_Tp>)

    return __b < __a ? pair<const _Tp&, const _Tp&>(__b, __a)
       : pair<const _Tp&, const _Tp&>(__a, __b);
  }

/**
 *  @brief  Determines min and max at once as an ordered pair.
 *  @ingroup sorting_algorithms
 *  @param  __a  A thing of arbitrary type.
 *  @param  __b  Another thing of arbitrary type.
 *  @param  __comp  A @link comparison_functors comparison functor @endlink.
 *  @return A pair(__b, __a) if __b is smaller than __a, pair(__a,
 *  __b) otherwise.
*/
template<typename _Tp, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline pair<const _Tp&, const _Tp&>
  minmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
  {
    return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a)
	      : pair<const _Tp&, const _Tp&>(__a, __b);
  }

template<typename _ForwardIterator, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  pair<_ForwardIterator, _ForwardIterator>
  __minmax_element(_ForwardIterator __first, _ForwardIterator __last,
     _Compare __comp)
  {
    _ForwardIterator __next = __first;
    if (__first == __last
 || ++__next == __last)
return std::make_pair(__first, __first);

    _ForwardIterator __min{}, __max{};
    if (__comp(__next, __first))
{
 __min = __next;
 __max = __first;
}
    else
{
 __min = __first;
 __max = __next;
}

    __first = __next;
    ++__first;

    while (__first != __last)
{
 __next = __first;
 if (++__next == __last)
   {
     if (__comp(__first, __min))
__min = __first;
     else if (!__comp(__first, __max))
__max = __first;
     break;
   }

 if (__comp(__next, __first))
   {
     if (__comp(__next, __min))
__min = __next;
     if (!__comp(__first, __max))
__max = __first;
   }
 else
   {
     if (__comp(__first, __min))
__min = __first;
     if (!__comp(__next, __max))
__max = __next;
   }

 __first = __next;
 ++__first;
}

    return std::make_pair(__min, __max);
  }

/**
 *  @brief  Return a pair of iterators pointing to the minimum and maximum
 *          elements in a range.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @return  make_pair(m, M), where m is the first iterator i in 
 *           [__first, __last) such that no other element in the range is
 *           smaller, and where M is the last iterator i in [__first, __last)
 *           such that no other element in the range is larger.
*/
template<typename _ForwardIterator>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline pair<_ForwardIterator, _ForwardIterator>
  minmax_element(_ForwardIterator __first, _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    return std::__minmax_element(__first, __last,
		   __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Return a pair of iterators pointing to the minimum and maximum
 *          elements in a range.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @param  __comp   Comparison functor.
 *  @return  make_pair(m, M), where m is the first iterator i in 
 *           [__first, __last) such that no other element in the range is
 *           smaller, and where M is the last iterator i in [__first, __last)
 *           such that no other element in the range is larger.
*/
template<typename _ForwardIterator, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline pair<_ForwardIterator, _ForwardIterator>
  minmax_element(_ForwardIterator __first, _ForwardIterator __last,
   _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_ForwardIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    return std::__minmax_element(__first, __last,
		   __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

// N2722 + DR 915.
template<typename _Tp>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _Tp
  min(initializer_list<_Tp> __l)
  { return *std::min_element(__l.begin(), __l.end()); }

template<typename _Tp, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _Tp
  min(initializer_list<_Tp> __l, _Compare __comp)
  { return *std::min_element(__l.begin(), __l.end(), __comp); }

template<typename _Tp>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _Tp
  max(initializer_list<_Tp> __l)
  { return *std::max_element(__l.begin(), __l.end()); }

template<typename _Tp, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _Tp
  max(initializer_list<_Tp> __l, _Compare __comp)
  { return *std::max_element(__l.begin(), __l.end(), __comp); }

template<typename _Tp>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline pair<_Tp, _Tp>
  minmax(initializer_list<_Tp> __l)
  {
    pair<const _Tp*, const _Tp*> __p =
std::minmax_element(__l.begin(), __l.end());
    return std::make_pair(*__p.first, *__p.second);
  }

template<typename _Tp, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline pair<_Tp, _Tp>
  minmax(initializer_list<_Tp> __l, _Compare __comp)
  {
    pair<const _Tp*, const _Tp*> __p =
std::minmax_element(__l.begin(), __l.end(), __comp);
    return std::make_pair(*__p.first, *__p.second);
  }

template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  bool
  __is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
     _ForwardIterator2 __first2, _BinaryPredicate __pred)
  {
    // Efficiently compare identical prefixes:  O(N) if sequences
    // have the same elements in the same order.
    for (; __first1 != __last1; ++__first1, (void)++__first2)
if (!__pred(__first1, __first2))
 break;

    if (__first1 == __last1)
return true;

    // Establish __last2 assuming equal ranges by iterating over the
    // rest of the list.
    _ForwardIterator2 __last2 = __first2;
    std::advance(__last2, std::distance(__first1, __last1));
    for (_ForwardIterator1 __scan = __first1; __scan != __last1; ++__scan)
{
 if (__scan != std::__find_if(__first1, __scan,
	  __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan)))
   continue; // We've seen this one before.
 
 auto __matches
   = std::__count_if(__first2, __last2,
	__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan));
 if (0 == __matches ||
     std::__count_if(__scan, __last1,
	__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan))
     != __matches)
   return false;
}
    return true;
  }

/**
 *  @brief  Checks whether a permutation of the second sequence is equal
 *          to the first sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @return true if there exists a permutation of the elements in the range
 *          [__first2, __first2 + (__last1 - __first1)), beginning with 
 *          ForwardIterator2 begin, such that equal(__first1, __last1, begin)
 *          returns true; otherwise, returns false.
*/
template<typename _ForwardIterator1, typename _ForwardIterator2>
  inline bool
  is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
   _ForwardIterator2 __first2)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
    __glibcxx_function_requires(_EqualOpConcept<
typename iterator_traits<_ForwardIterator1>::value_type,
typename iterator_traits<_ForwardIterator2>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);

    return std::__is_permutation(__first1, __last1, __first2,
		   __gnu_cxx::__ops::__iter_equal_to_iter());
  }

/**
 *  @brief  Checks whether a permutation of the second sequence is equal
 *          to the first sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __pred    A binary predicate.
 *  @return true if there exists a permutation of the elements in
 *          the range [__first2, __first2 + (__last1 - __first1)),
 *          beginning with ForwardIterator2 begin, such that
 *          equal(__first1, __last1, __begin, __pred) returns true;
 *          otherwise, returns false.
*/
template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  inline bool
  is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
   _ForwardIterator2 __first2, _BinaryPredicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
   typename iterator_traits<_ForwardIterator1>::value_type,
   typename iterator_traits<_ForwardIterator2>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);

    return std::__is_permutation(__first1, __last1, __first2,
		   __gnu_cxx::__ops::__iter_comp_iter(__pred));
  }

3586#if __cplusplus201402L > 201103L
template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  bool
  __is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
     _ForwardIterator2 __first2, _ForwardIterator2 __last2,
     _BinaryPredicate __pred)
  {
    using _Cat1
= typename iterator_traits<_ForwardIterator1>::iterator_category;
    using _Cat2
= typename iterator_traits<_ForwardIterator2>::iterator_category;
    using _It1_is_RA = is_same<_Cat1, random_access_iterator_tag>;
    using _It2_is_RA = is_same<_Cat2, random_access_iterator_tag>;
    constexpr bool __ra_iters = _It1_is_RA() && _It2_is_RA();
    if (__ra_iters)
{
 auto __d1 = std::distance(__first1, __last1);
 auto __d2 = std::distance(__first2, __last2);
 if (__d1 != __d2)
   return false;
}

    // Efficiently compare identical prefixes:  O(N) if sequences
    // have the same elements in the same order.
    for (; __first1 != __last1 && __first2 != __last2;
 ++__first1, (void)++__first2)
if (!__pred(__first1, __first2))
 break;

    if (__ra_iters)
{
 if (__first1 == __last1)
   return true;
}
    else
{
 auto __d1 = std::distance(__first1, __last1);
 auto __d2 = std::distance(__first2, __last2);
 if (__d1 == 0 && __d2 == 0)
   return true;
 if (__d1 != __d2)
   return false;
}

    for (_ForwardIterator1 __scan = __first1; __scan != __last1; ++__scan)
{
 if (__scan != std::__find_if(__first1, __scan,
	__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan)))
   continue; // We've seen this one before.

 auto __matches = std::__count_if(__first2, __last2,
__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan));
 if (0 == __matches
     || std::__count_if(__scan, __last1,
	__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan))
     != __matches)
   return false;
}
    return true;
  }

/**
 *  @brief  Checks whether a permutaion of the second sequence is equal
 *          to the first sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of first range.
 *  @return true if there exists a permutation of the elements in the range
 *          [__first2, __last2), beginning with ForwardIterator2 begin,
 *          such that equal(__first1, __last1, begin) returns true;
 *          otherwise, returns false.
*/
template<typename _ForwardIterator1, typename _ForwardIterator2>
  inline bool
  is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
   _ForwardIterator2 __first2, _ForwardIterator2 __last2)
  {
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    return
std::__is_permutation(__first1, __last1, __first2, __last2,
	      __gnu_cxx::__ops::__iter_equal_to_iter());
  }

/**
 *  @brief  Checks whether a permutation of the second sequence is equal
 *          to the first sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of first range.
 *  @param  __pred    A binary predicate.
 *  @return true if there exists a permutation of the elements in the range
 *          [__first2, __last2), beginning with ForwardIterator2 begin,
 *          such that equal(__first1, __last1, __begin, __pred) returns true;
 *          otherwise, returns false.
*/
template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  inline bool
  is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
   _ForwardIterator2 __first2, _ForwardIterator2 __last2,
   _BinaryPredicate __pred)
  {
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    return std::__is_permutation(__first1, __last1, __first2, __last2,
		   __gnu_cxx::__ops::__iter_comp_iter(__pred));
  }
3701#endif

3703#ifdef _GLIBCXX_USE_C99_STDINT_TR11
/**
 *  @brief Shuffle the elements of a sequence using a uniform random
 *         number generator.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __last    A forward iterator.
 *  @param  __g       A UniformRandomNumberGenerator (26.5.1.3).
 *  @return  Nothing.
 *
 *  Reorders the elements in the range @p [__first,__last) using @p __g to
 *  provide random numbers.
*/
template<typename _RandomAccessIterator,
  typename _UniformRandomNumberGenerator>
  void
  shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
   _UniformRandomNumberGenerator&& __g)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_requires_valid_range(__first, __last);

    if (__first == __last)
return;

    typedef typename iterator_traits<_RandomAccessIterator>::difference_type
_DistanceType;

    typedef typename std::make_unsigned<_DistanceType>::type __ud_type;
    typedef typename std::uniform_int_distribution<__ud_type> __distr_type;
    typedef typename __distr_type::param_type __p_type;
    __distr_type __d;

    for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
std::iter_swap(__i, __first + __d(__g, __p_type(0, __i - __first)));
  }
3741#endif

3743#endif // C++11

3745_GLIBCXX_END_NAMESPACE_VERSION

3747_GLIBCXX_BEGIN_NAMESPACE_ALGO

/**
 *  @brief Apply a function to every element of a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __f      A unary function object.
 *  @return   @p __f (std::move(@p __f) in C++0x).
 *
 *  Applies the function object @p __f to each element in the range
 *  @p [first,last).  @p __f must not modify the order of the sequence.
 *  If @p __f has a return value it is ignored.
*/
template<typename _InputIterator, typename _Function>
  _Function
  for_each(_InputIterator __first, _InputIterator __last, _Function __f)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_requires_valid_range(__first, __last);
    for (; __first != __last; ++__first)
__f(*__first);
    return _GLIBCXX_MOVE(__f)std::move(__f);
  }

/**
 *  @brief Find the first occurrence of a value in a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __val    The value to find.
 *  @return   The first iterator @c i in the range @p [__first,__last)
 *  such that @c *i == @p __val, or @p __last if no such iterator exists.
*/
template<typename _InputIterator, typename _Tp>
  inline _InputIterator
  find(_InputIterator __first, _InputIterator __last,
const _Tp& __val)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_EqualOpConcept<
typename iterator_traits<_InputIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);
    return std::__find_if(__first, __last,
	    __gnu_cxx::__ops::__iter_equals_val(__val));
  }

/**
 *  @brief Find the first element in a sequence for which a
 *         predicate is true.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __pred   A predicate.
 *  @return   The first iterator @c i in the range @p [__first,__last)
 *  such that @p __pred(*i) is true, or @p __last if no such iterator exists.
*/
template<typename _InputIterator, typename _Predicate>
  inline _InputIterator
  find_if(_InputIterator __first, _InputIterator __last,
   _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
     typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__find_if(__first, __last,
	    __gnu_cxx::__ops::__pred_iter(__pred));
  }

/**
 *  @brief  Find element from a set in a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of range to search.
 *  @param  __last1   End of range to search.
 *  @param  __first2  Start of match candidates.
 *  @param  __last2   End of match candidates.
 *  @return   The first iterator @c i in the range
 *  @p [__first1,__last1) such that @c *i == @p *(i2) such that i2 is an
 *  iterator in [__first2,__last2), or @p __last1 if no such iterator exists.
 *
 *  Searches the range @p [__first1,__last1) for an element that is
 *  equal to some element in the range [__first2,__last2).  If
 *  found, returns an iterator in the range [__first1,__last1),
 *  otherwise returns @p __last1.
*/
template<typename _InputIterator, typename _ForwardIterator>
  _InputIterator
  find_first_of(_InputIterator __first1, _InputIterator __last1,
  _ForwardIterator __first2, _ForwardIterator __last2)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_InputIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    for (; __first1 != __last1; ++__first1)
for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter)
 if (*__first1 == *__iter)
   return __first1;
    return __last1;
  }

/**
 *  @brief  Find element from a set in a sequence using a predicate.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  Start of range to search.
 *  @param  __last1   End of range to search.
 *  @param  __first2  Start of match candidates.
 *  @param  __last2   End of match candidates.
 *  @param  __comp    Predicate to use.
 *  @return   The first iterator @c i in the range
 *  @p [__first1,__last1) such that @c comp(*i, @p *(i2)) is true
 *  and i2 is an iterator in [__first2,__last2), or @p __last1 if no
 *  such iterator exists.
 *

 *  Searches the range @p [__first1,__last1) for an element that is
 *  equal to some element in the range [__first2,__last2).  If
 *  found, returns an iterator in the range [__first1,__last1),
 *  otherwise returns @p __last1.
*/
template<typename _InputIterator, typename _ForwardIterator,
  typename _BinaryPredicate>
  _InputIterator
  find_first_of(_InputIterator __first1, _InputIterator __last1,
  _ForwardIterator __first2, _ForwardIterator __last2,
  _BinaryPredicate __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
   typename iterator_traits<_InputIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    for (; __first1 != __last1; ++__first1)
for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter)
 if (__comp(*__first1, *__iter))
   return __first1;
    return __last1;
  }

/**
 *  @brief Find two adjacent values in a sequence that are equal.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  A forward iterator.
 *  @param  __last   A forward iterator.
 *  @return   The first iterator @c i such that @c i and @c i+1 are both
 *  valid iterators in @p [__first,__last) and such that @c *i == @c *(i+1),
 *  or @p __last if no such iterator exists.
*/
template<typename _ForwardIterator>
  inline _ForwardIterator
  adjacent_find(_ForwardIterator __first, _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_EqualityComparableConcept<
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__adjacent_find(__first, __last,
		  __gnu_cxx::__ops::__iter_equal_to_iter());
  }

/**
 *  @brief Find two adjacent values in a sequence using a predicate.
 *  @ingroup non_mutating_algorithms
 *  @param  __first         A forward iterator.
 *  @param  __last          A forward iterator.
 *  @param  __binary_pred   A binary predicate.
 *  @return   The first iterator @c i such that @c i and @c i+1 are both
 *  valid iterators in @p [__first,__last) and such that
 *  @p __binary_pred(*i,*(i+1)) is true, or @p __last if no such iterator
 *  exists.
*/
template<typename _ForwardIterator, typename _BinaryPredicate>
  inline _ForwardIterator
  adjacent_find(_ForwardIterator __first, _ForwardIterator __last,
  _BinaryPredicate __binary_pred)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
   typename iterator_traits<_ForwardIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__adjacent_find(__first, __last,
	__gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
  }

/**
 *  @brief Count the number of copies of a value in a sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __value  The value to be counted.
 *  @return   The number of iterators @c i in the range @p [__first,__last)
 *  for which @c *i == @p __value
*/
template<typename _InputIterator, typename _Tp>
  inline typename iterator_traits<_InputIterator>::difference_type
  count(_InputIterator __first, _InputIterator __last, const _Tp& __value)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_InputIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__count_if(__first, __last,
	     __gnu_cxx::__ops::__iter_equals_val(__value));
  }

/**
 *  @brief Count the elements of a sequence for which a predicate is true.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  An input iterator.
 *  @param  __last   An input iterator.
 *  @param  __pred   A predicate.
 *  @return   The number of iterators @c i in the range @p [__first,__last)
 *  for which @p __pred(*i) is true.
*/
template<typename _InputIterator, typename _Predicate>
  inline typename iterator_traits<_InputIterator>::difference_type
  count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__count_if(__first, __last,
	     __gnu_cxx::__ops::__pred_iter(__pred));
  }

/**
 *  @brief Search a sequence for a matching sub-sequence.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1  A forward iterator.
 *  @param  __last1   A forward iterator.
 *  @param  __first2  A forward iterator.
 *  @param  __last2   A forward iterator.
 *  @return The first iterator @c i in the range @p
 *  [__first1,__last1-(__last2-__first2)) such that @c *(i+N) == @p
 *  *(__first2+N) for each @c N in the range @p
 *  [0,__last2-__first2), or @p __last1 if no such iterator exists.
 *
 *  Searches the range @p [__first1,__last1) for a sub-sequence that
 *  compares equal value-by-value with the sequence given by @p
 *  [__first2,__last2) and returns an iterator to the first element
 *  of the sub-sequence, or @p __last1 if the sub-sequence is not
 *  found.
 *
 *  Because the sub-sequence must lie completely within the range @p
 *  [__first1,__last1) it must start at a position less than @p
 *  __last1-(__last2-__first2) where @p __last2-__first2 is the
 *  length of the sub-sequence.
 *
 *  This means that the returned iterator @c i will be in the range
 *  @p [__first1,__last1-(__last2-__first2))
*/
template<typename _ForwardIterator1, typename _ForwardIterator2>
  inline _ForwardIterator1
  search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
  _ForwardIterator2 __first2, _ForwardIterator2 __last2)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_ForwardIterator1>::value_type,
   typename iterator_traits<_ForwardIterator2>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    return std::__search(__first1, __last1, __first2, __last2,
	   __gnu_cxx::__ops::__iter_equal_to_iter());
  }

/**
 *  @brief Search a sequence for a matching sub-sequence using a predicate.
 *  @ingroup non_mutating_algorithms
 *  @param  __first1     A forward iterator.
 *  @param  __last1      A forward iterator.
 *  @param  __first2     A forward iterator.
 *  @param  __last2      A forward iterator.
 *  @param  __predicate  A binary predicate.
 *  @return   The first iterator @c i in the range
 *  @p [__first1,__last1-(__last2-__first2)) such that
 *  @p __predicate(*(i+N),*(__first2+N)) is true for each @c N in the range
 *  @p [0,__last2-__first2), or @p __last1 if no such iterator exists.
 *
 *  Searches the range @p [__first1,__last1) for a sub-sequence that
 *  compares equal value-by-value with the sequence given by @p
 *  [__first2,__last2), using @p __predicate to determine equality,
 *  and returns an iterator to the first element of the
 *  sub-sequence, or @p __last1 if no such iterator exists.
 *
 *  @see search(_ForwardIter1, _ForwardIter1, _ForwardIter2, _ForwardIter2)
*/
template<typename _ForwardIterator1, typename _ForwardIterator2,
  typename _BinaryPredicate>
  inline _ForwardIterator1
  search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
  _ForwardIterator2 __first2, _ForwardIterator2 __last2,
  _BinaryPredicate  __predicate)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
   typename iterator_traits<_ForwardIterator1>::value_type,
   typename iterator_traits<_ForwardIterator2>::value_type>)
    __glibcxx_requires_valid_range(__first1, __last1);
    __glibcxx_requires_valid_range(__first2, __last2);

    return std::__search(__first1, __last1, __first2, __last2,
	   __gnu_cxx::__ops::__iter_comp_iter(__predicate));
  }

/**
 *  @brief Search a sequence for a number of consecutive values.
 *  @ingroup non_mutating_algorithms
 *  @param  __first  A forward iterator.
 *  @param  __last   A forward iterator.
 *  @param  __count  The number of consecutive values.
 *  @param  __val    The value to find.
 *  @return The first iterator @c i in the range @p
 *  [__first,__last-__count) such that @c *(i+N) == @p __val for
 *  each @c N in the range @p [0,__count), or @p __last if no such
 *  iterator exists.
 *
 *  Searches the range @p [__first,__last) for @p count consecutive elements
 *  equal to @p __val.
*/
template<typename _ForwardIterator, typename _Integer, typename _Tp>
  inline _ForwardIterator
  search_n(_ForwardIterator __first, _ForwardIterator __last,
    _Integer __count, const _Tp& __val)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__search_n(__first, __last, __count,
	     __gnu_cxx::__ops::__iter_equals_val(__val));
  }


/**
 *  @brief Search a sequence for a number of consecutive values using a
 *         predicate.
 *  @ingroup non_mutating_algorithms
 *  @param  __first        A forward iterator.
 *  @param  __last         A forward iterator.
 *  @param  __count        The number of consecutive values.
 *  @param  __val          The value to find.
 *  @param  __binary_pred  A binary predicate.
 *  @return The first iterator @c i in the range @p
 *  [__first,__last-__count) such that @p
 *  __binary_pred(*(i+N),__val) is true for each @c N in the range
 *  @p [0,__count), or @p __last if no such iterator exists.
 *
 *  Searches the range @p [__first,__last) for @p __count
 *  consecutive elements for which the predicate returns true.
*/
template<typename _ForwardIterator, typename _Integer, typename _Tp,
  typename _BinaryPredicate>
  inline _ForwardIterator
  search_n(_ForwardIterator __first, _ForwardIterator __last,
    _Integer __count, const _Tp& __val,
    _BinaryPredicate __binary_pred)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
   typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__search_n(__first, __last, __count,
__gnu_cxx::__ops::__iter_comp_val(__binary_pred, __val));
  }


/**
 *  @brief Perform an operation on a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first     An input iterator.
 *  @param  __last      An input iterator.
 *  @param  __result    An output iterator.
 *  @param  __unary_op  A unary operator.
 *  @return   An output iterator equal to @p __result+(__last-__first).
 *
 *  Applies the operator to each element in the input range and assigns
 *  the results to successive elements of the output sequence.
 *  Evaluates @p *(__result+N)=unary_op(*(__first+N)) for each @c N in the
 *  range @p [0,__last-__first).
 *
 *  @p unary_op must not alter its argument.
*/
template<typename _InputIterator, typename _OutputIterator,
  typename _UnaryOperation>
  _OutputIterator
  transform(_InputIterator __first, _InputIterator __last,
     _OutputIterator __result, _UnaryOperation __unary_op)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   // "the type returned by a _UnaryOperation"
   __typeof__(__unary_op(*__first))>)
    __glibcxx_requires_valid_range(__first, __last);

    for (; __first != __last; ++__first, (void)++__result)
*__result = __unary_op(*__first);
    return __result;
  }

/**
 *  @brief Perform an operation on corresponding elements of two sequences.
 *  @ingroup mutating_algorithms
 *  @param  __first1     An input iterator.
 *  @param  __last1      An input iterator.
 *  @param  __first2     An input iterator.
 *  @param  __result     An output iterator.
 *  @param  __binary_op  A binary operator.
 *  @return   An output iterator equal to @p result+(last-first).
 *
 *  Applies the operator to the corresponding elements in the two
 *  input ranges and assigns the results to successive elements of the
 *  output sequence.
 *  Evaluates @p
 *  *(__result+N)=__binary_op(*(__first1+N),*(__first2+N)) for each
 *  @c N in the range @p [0,__last1-__first1).
 *
 *  @p binary_op must not alter either of its arguments.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _BinaryOperation>
  _OutputIterator
  transform(_InputIterator1 __first1, _InputIterator1 __last1,
     _InputIterator2 __first2, _OutputIterator __result,
     _BinaryOperation __binary_op)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   // "the type returned by a _BinaryOperation"
   __typeof__(__binary_op(*__first1,*__first2))>)
    __glibcxx_requires_valid_range(__first1, __last1);

    for (; __first1 != __last1; ++__first1, (void)++__first2, ++__result)
*__result = __binary_op(*__first1, *__first2);
    return __result;
  }

/**
 *  @brief Replace each occurrence of one value in a sequence with another
 *         value.
 *  @ingroup mutating_algorithms
 *  @param  __first      A forward iterator.
 *  @param  __last       A forward iterator.
 *  @param  __old_value  The value to be replaced.
 *  @param  __new_value  The replacement value.
 *  @return   replace() returns no value.
 *
 *  For each iterator @c i in the range @p [__first,__last) if @c *i ==
 *  @p __old_value then the assignment @c *i = @p __new_value is performed.
*/
template<typename _ForwardIterator, typename _Tp>
  void
  replace(_ForwardIterator __first, _ForwardIterator __last,
   const _Tp& __old_value, const _Tp& __new_value)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_EqualOpConcept<
   typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
    __glibcxx_function_requires(_ConvertibleConcept<_Tp,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    for (; __first != __last; ++__first)
if (*__first == __old_value)
 *__first = __new_value;
  }

/**
 *  @brief Replace each value in a sequence for which a predicate returns
 *         true with another value.
 *  @ingroup mutating_algorithms
 *  @param  __first      A forward iterator.
 *  @param  __last       A forward iterator.
 *  @param  __pred       A predicate.
 *  @param  __new_value  The replacement value.
 *  @return   replace_if() returns no value.
 *
 *  For each iterator @c i in the range @p [__first,__last) if @p __pred(*i)
 *  is true then the assignment @c *i = @p __new_value is performed.
*/
template<typename _ForwardIterator, typename _Predicate, typename _Tp>
  void
  replace_if(_ForwardIterator __first, _ForwardIterator __last,
      _Predicate __pred, const _Tp& __new_value)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_ConvertibleConcept<_Tp,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    for (; __first != __last; ++__first)
if (__pred(*__first))
 *__first = __new_value;
  }

/**
 *  @brief Assign the result of a function object to each value in a
 *         sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first  A forward iterator.
 *  @param  __last   A forward iterator.
 *  @param  __gen    A function object taking no arguments and returning
 *                 std::iterator_traits<_ForwardIterator>::value_type
 *  @return   generate() returns no value.
 *
 *  Performs the assignment @c *i = @p __gen() for each @c i in the range
 *  @p [__first,__last).
*/
template<typename _ForwardIterator, typename _Generator>
  void
  generate(_ForwardIterator __first, _ForwardIterator __last,
    _Generator __gen)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_GeneratorConcept<_Generator,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    for (; __first != __last; ++__first)
*__first = __gen();
  }

/**
 *  @brief Assign the result of a function object to each value in a
 *         sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first  A forward iterator.
 *  @param  __n      The length of the sequence.
 *  @param  __gen    A function object taking no arguments and returning
 *                 std::iterator_traits<_ForwardIterator>::value_type
 *  @return   The end of the sequence, @p __first+__n
 *
 *  Performs the assignment @c *i = @p __gen() for each @c i in the range
 *  @p [__first,__first+__n).
 *
 *  _GLIBCXX_RESOLVE_LIB_DEFECTS
 *  DR 865. More algorithms that throw away information
*/
template<typename _OutputIterator, typename _Size, typename _Generator>
  _OutputIterator
  generate_n(_OutputIterator __first, _Size __n, _Generator __gen)
  {
    // concept requirements
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   // "the type returned by a _Generator"
   __typeof__(__gen())>)

    for (__decltype(__n + 0) __niter = __n;
  __niter > 0; --__niter, ++__first)
*__first = __gen();
    return __first;
  }

/**
 *  @brief Copy a sequence, removing consecutive duplicate values.
 *  @ingroup mutating_algorithms
 *  @param  __first   An input iterator.
 *  @param  __last    An input iterator.
 *  @param  __result  An output iterator.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  Copies each element in the range @p [__first,__last) to the range
 *  beginning at @p __result, except that only the first element is copied
 *  from groups of consecutive elements that compare equal.
 *  unique_copy() is stable, so the relative order of elements that are
 *  copied is unchanged.
 *
 *  _GLIBCXX_RESOLVE_LIB_DEFECTS
 *  DR 241. Does unique_copy() require CopyConstructible and Assignable?
 *  
 *  _GLIBCXX_RESOLVE_LIB_DEFECTS
 *  DR 538. 241 again: Does unique_copy() require CopyConstructible and 
 *  Assignable?
*/
template<typename _InputIterator, typename _OutputIterator>
  inline _OutputIterator
  unique_copy(_InputIterator __first, _InputIterator __last,
_OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_function_requires(_EqualityComparableConcept<
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    if (__first == __last)
return __result;
    return std::__unique_copy(__first, __last, __result,
		__gnu_cxx::__ops::__iter_equal_to_iter(),
		std::__iterator_category(__first),
		std::__iterator_category(__result));
  }

/**
 *  @brief Copy a sequence, removing consecutive values using a predicate.
 *  @ingroup mutating_algorithms
 *  @param  __first        An input iterator.
 *  @param  __last         An input iterator.
 *  @param  __result       An output iterator.
 *  @param  __binary_pred  A binary predicate.
 *  @return   An iterator designating the end of the resulting sequence.
 *
 *  Copies each element in the range @p [__first,__last) to the range
 *  beginning at @p __result, except that only the first element is copied
 *  from groups of consecutive elements for which @p __binary_pred returns
 *  true.
 *  unique_copy() is stable, so the relative order of elements that are
 *  copied is unchanged.
 *
 *  _GLIBCXX_RESOLVE_LIB_DEFECTS
 *  DR 241. Does unique_copy() require CopyConstructible and Assignable?
*/
template<typename _InputIterator, typename _OutputIterator,
  typename _BinaryPredicate>
  inline _OutputIterator
  unique_copy(_InputIterator __first, _InputIterator __last,
_OutputIterator __result,
_BinaryPredicate __binary_pred)
  {
    // concept requirements -- predicates checked later
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    if (__first == __last)
return __result;
    return std::__unique_copy(__first, __last, __result,
	__gnu_cxx::__ops::__iter_comp_iter(__binary_pred),
		std::__iterator_category(__first),
		std::__iterator_category(__result));
  }

4425#if _GLIBCXX_HOSTED1
/**
 *  @brief Randomly shuffle the elements of a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __last    A forward iterator.
 *  @return  Nothing.
 *
 *  Reorder the elements in the range @p [__first,__last) using a random
 *  distribution, so that every possible ordering of the sequence is
 *  equally likely.
*/
template<typename _RandomAccessIterator>
  inline void
  random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_requires_valid_range(__first, __last);

    if (__first != __last)
for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
 {
   // XXX rand() % N is not uniformly distributed
   _RandomAccessIterator __j = __first
			+ std::rand() % ((__i - __first) + 1);
   if (__i != __j)
     std::iter_swap(__i, __j);
 }
  }
4456#endif

/**
 *  @brief Shuffle the elements of a sequence using a random number
 *         generator.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __last    A forward iterator.
 *  @param  __rand    The RNG functor or function.
 *  @return  Nothing.
 *
 *  Reorders the elements in the range @p [__first,__last) using @p __rand to
 *  provide a random distribution. Calling @p __rand(N) for a positive
 *  integer @p N should return a randomly chosen integer from the
 *  range [0,N).
*/
template<typename _RandomAccessIterator, typename _RandomNumberGenerator>
  void
  random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
4475#if __cplusplus201402L >= 201103L
   _RandomNumberGenerator&& __rand)
4477#else
   _RandomNumberGenerator& __rand)
4479#endif
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_requires_valid_range(__first, __last);

    if (__first == __last)
return;
    for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
{
 _RandomAccessIterator __j = __first + __rand((__i - __first) + 1);
 if (__i != __j)
   std::iter_swap(__i, __j);
}
  }


/**
 *  @brief Move elements for which a predicate is true to the beginning
 *         of a sequence.
 *  @ingroup mutating_algorithms
 *  @param  __first   A forward iterator.
 *  @param  __last    A forward iterator.
 *  @param  __pred    A predicate functor.
 *  @return  An iterator @p middle such that @p __pred(i) is true for each
 *  iterator @p i in the range @p [__first,middle) and false for each @p i
 *  in the range @p [middle,__last).
 *
 *  @p __pred must not modify its operand. @p partition() does not preserve
 *  the relative ordering of elements in each group, use
 *  @p stable_partition() if this is needed.
*/
template<typename _ForwardIterator, typename _Predicate>
  inline _ForwardIterator
  partition(_ForwardIterator __first, _ForwardIterator __last,
     _Predicate   __pred)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
		  _ForwardIterator>)
    __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);

    return std::__partition(__first, __last, __pred,
	      std::__iterator_category(__first));
  }


/**
 *  @brief Sort the smallest elements of a sequence.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __middle  Another iterator.
 *  @param  __last    Another iterator.
 *  @return  Nothing.
 *
 *  Sorts the smallest @p (__middle-__first) elements in the range
 *  @p [first,last) and moves them to the range @p [__first,__middle). The
 *  order of the remaining elements in the range @p [__middle,__last) is
 *  undefined.
 *  After the sort if @e i and @e j are iterators in the range
 *  @p [__first,__middle) such that i precedes j and @e k is an iterator in
 *  the range @p [__middle,__last) then *j<*i and *k<*i are both false.
*/
template<typename _RandomAccessIterator>
  inline void
  partial_sort(_RandomAccessIterator __first,
 _RandomAccessIterator __middle,
 _RandomAccessIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __middle);
    __glibcxx_requires_valid_range(__middle, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    std::__partial_sort(__first, __middle, __last,
	  __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Sort the smallest elements of a sequence using a predicate
 *         for comparison.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __middle  Another iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A comparison functor.
 *  @return  Nothing.
 *
 *  Sorts the smallest @p (__middle-__first) elements in the range
 *  @p [__first,__last) and moves them to the range @p [__first,__middle). The
 *  order of the remaining elements in the range @p [__middle,__last) is
 *  undefined.
 *  After the sort if @e i and @e j are iterators in the range
 *  @p [__first,__middle) such that i precedes j and @e k is an iterator in
 *  the range @p [__middle,__last) then @p *__comp(j,*i) and @p __comp(*k,*i)
 *  are both false.
*/
template<typename _RandomAccessIterator, typename _Compare>
  inline void
  partial_sort(_RandomAccessIterator __first,
 _RandomAccessIterator __middle,
 _RandomAccessIterator __last,
 _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_RandomAccessIterator>::value_type,
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __middle);
    __glibcxx_requires_valid_range(__middle, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    std::__partial_sort(__first, __middle, __last,
	  __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

/**
 *  @brief Sort a sequence just enough to find a particular position.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __nth     Another iterator.
 *  @param  __last    Another iterator.
 *  @return  Nothing.
 *
 *  Rearranges the elements in the range @p [__first,__last) so that @p *__nth
 *  is the same element that would have been in that position had the
 *  whole sequence been sorted. The elements either side of @p *__nth are
 *  not completely sorted, but for any iterator @e i in the range
 *  @p [__first,__nth) and any iterator @e j in the range @p [__nth,__last) it
 *  holds that *j < *i is false.
*/
template<typename _RandomAccessIterator>
  inline void
  nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth,
_RandomAccessIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
		  _RandomAccessIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __nth);
    __glibcxx_requires_valid_range(__nth, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    if (__first == __last || __nth == __last)
return;

    std::__introselect(__first, __nth, __last,
	 std::__lg(__last - __first) * 2,
	 __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Sort a sequence just enough to find a particular position
 *         using a predicate for comparison.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __nth     Another iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A comparison functor.
 *  @return  Nothing.
 *
 *  Rearranges the elements in the range @p [__first,__last) so that @p *__nth
 *  is the same element that would have been in that position had the
 *  whole sequence been sorted. The elements either side of @p *__nth are
 *  not completely sorted, but for any iterator @e i in the range
 *  @p [__first,__nth) and any iterator @e j in the range @p [__nth,__last) it
 *  holds that @p __comp(*j,*i) is false.
*/
template<typename _RandomAccessIterator, typename _Compare>
  inline void
  nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth,
_RandomAccessIterator __last, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
		  _RandomAccessIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_RandomAccessIterator>::value_type,
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __nth);
    __glibcxx_requires_valid_range(__nth, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    if (__first == __last || __nth == __last)
return;

    std::__introselect(__first, __nth, __last,
	 std::__lg(__last - __first) * 2,
	 __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

/**
 *  @brief Sort the elements of a sequence.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @return  Nothing.
 *
 *  Sorts the elements in the range @p [__first,__last) in ascending order,
 *  such that for each iterator @e i in the range @p [__first,__last-1),  
 *  *(i+1)<*i is false.
 *
 *  The relative ordering of equivalent elements is not preserved, use
 *  @p stable_sort() if this is needed.
*/
template<typename _RandomAccessIterator>
  inline void
  sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    std::__sort(__first, __last, __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Sort the elements of a sequence using a predicate for comparison.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A comparison functor.
 *  @return  Nothing.
 *
 *  Sorts the elements in the range @p [__first,__last) in ascending order,
 *  such that @p __comp(*(i+1),*i) is false for every iterator @e i in the
 *  range @p [__first,__last-1).
 *
 *  The relative ordering of equivalent elements is not preserved, use
 *  @p stable_sort() if this is needed.
*/
template<typename _RandomAccessIterator, typename _Compare>
  inline void
  sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
_Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_RandomAccessIterator>::value_type,
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    std::__sort(__first, __last, __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  _OutputIterator
  __merge(_InputIterator1 __first1, _InputIterator1 __last1,
   _InputIterator2 __first2, _InputIterator2 __last2,
   _OutputIterator __result, _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
{
 if (__comp(__first2, __first1))
   {
     *__result = *__first2;
     ++__first2;
   }
 else
   {
     *__result = *__first1;
     ++__first1;
   }
 ++__result;
}
    return std::copy(__first2, __last2,
       std::copy(__first1, __last1, __result));
  }

/**
 *  @brief Merges two sorted ranges.
 *  @ingroup sorting_algorithms
 *  @param  __first1  An iterator.
 *  @param  __first2  Another iterator.
 *  @param  __last1   Another iterator.
 *  @param  __last2   Another iterator.
 *  @param  __result  An iterator pointing to the end of the merged range.
 *  @return         An iterator pointing to the first element <em>not less
 *                  than</em> @e val.
 *
 *  Merges the ranges @p [__first1,__last1) and @p [__first2,__last2) into
 *  the sorted range @p [__result, __result + (__last1-__first1) +
 *  (__last2-__first2)).  Both input ranges must be sorted, and the
 *  output range must not overlap with either of the input ranges.
 *  The sort is @e stable, that is, for equivalent elements in the
 *  two ranges, elements from the first range will always come
 *  before elements from the second.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator>
  inline _OutputIterator
  merge(_InputIterator1 __first1, _InputIterator1 __last1,
 _InputIterator2 __first2, _InputIterator2 __last2,
 _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)	
    __glibcxx_requires_sorted_set(__first1, __last1, __first2);
    __glibcxx_requires_sorted_set(__first2, __last2, __first1);
    __glibcxx_requires_irreflexive2(__first1, __last1);
    __glibcxx_requires_irreflexive2(__first2, __last2);

    return _GLIBCXX_STD_Astd::__merge(__first1, __last1,
		     __first2, __last2, __result,
		     __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Merges two sorted ranges.
 *  @ingroup sorting_algorithms
 *  @param  __first1  An iterator.
 *  @param  __first2  Another iterator.
 *  @param  __last1   Another iterator.
 *  @param  __last2   Another iterator.
 *  @param  __result  An iterator pointing to the end of the merged range.
 *  @param  __comp    A functor to use for comparisons.
 *  @return         An iterator pointing to the first element "not less
 *                  than" @e val.
 *
 *  Merges the ranges @p [__first1,__last1) and @p [__first2,__last2) into
 *  the sorted range @p [__result, __result + (__last1-__first1) +
 *  (__last2-__first2)).  Both input ranges must be sorted, and the
 *  output range must not overlap with either of the input ranges.
 *  The sort is @e stable, that is, for equivalent elements in the
 *  two ranges, elements from the first range will always come
 *  before elements from the second.
 *
 *  The comparison function should have the same effects on ordering as
 *  the function used for the initial sort.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  inline _OutputIterator
  merge(_InputIterator1 __first1, _InputIterator1 __last1,
 _InputIterator2 __first2, _InputIterator2 __last2,
 _OutputIterator __result, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
    __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);

    return _GLIBCXX_STD_Astd::__merge(__first1, __last1,
		__first2, __last2, __result,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _RandomAccessIterator, typename _Compare>
  inline void
  __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
  _Compare __comp)
  {
    typedef typename iterator_traits<_RandomAccessIterator>::value_type
_ValueType;
    typedef typename iterator_traits<_RandomAccessIterator>::difference_type
_DistanceType;

    typedef _Temporary_buffer<_RandomAccessIterator, _ValueType> _TmpBuf;
    _TmpBuf __buf(__first, __last);

    if (__buf.begin() == 0)
std::__inplace_stable_sort(__first, __last, __comp);
    else
std::__stable_sort_adaptive(__first, __last, __buf.begin(),
		    _DistanceType(__buf.size()), __comp);
  }

/**
 *  @brief Sort the elements of a sequence, preserving the relative order
 *         of equivalent elements.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @return  Nothing.
 *
 *  Sorts the elements in the range @p [__first,__last) in ascending order,
 *  such that for each iterator @p i in the range @p [__first,__last-1),
 *  @p *(i+1)<*i is false.
 *
 *  The relative ordering of equivalent elements is preserved, so any two
 *  elements @p x and @p y in the range @p [__first,__last) such that
 *  @p x<y is false and @p y<x is false will have the same relative
 *  ordering after calling @p stable_sort().
*/
template<typename _RandomAccessIterator>
  inline void
  stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    _GLIBCXX_STD_Astd::__stable_sort(__first, __last,
		    __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Sort the elements of a sequence using a predicate for comparison,
 *         preserving the relative order of equivalent elements.
 *  @ingroup sorting_algorithms
 *  @param  __first   An iterator.
 *  @param  __last    Another iterator.
 *  @param  __comp    A comparison functor.
 *  @return  Nothing.
 *
 *  Sorts the elements in the range @p [__first,__last) in ascending order,
 *  such that for each iterator @p i in the range @p [__first,__last-1),
 *  @p __comp(*(i+1),*i) is false.
 *
 *  The relative ordering of equivalent elements is preserved, so any two
 *  elements @p x and @p y in the range @p [__first,__last) such that
 *  @p __comp(x,y) is false and @p __comp(y,x) is false will have the same
 *  relative ordering after calling @p stable_sort().
*/
template<typename _RandomAccessIterator, typename _Compare>
  inline void
  stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
_Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
   _RandomAccessIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_RandomAccessIterator>::value_type,
   typename iterator_traits<_RandomAccessIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    _GLIBCXX_STD_Astd::__stable_sort(__first, __last,
		    __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator,
  typename _Compare>
  _OutputIterator
  __set_union(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2, _InputIterator2 __last2,
_OutputIterator __result, _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
{
 if (__comp(__first1, __first2))
   {
     *__result = *__first1;
     ++__first1;
   }
 else if (__comp(__first2, __first1))
   {
     *__result = *__first2;
     ++__first2;
   }
 else
   {
     *__result = *__first1;
     ++__first1;
     ++__first2;
   }
 ++__result;
}
    return std::copy(__first2, __last2,
       std::copy(__first1, __last1, __result));
  }

/**
 *  @brief Return the union of two sorted ranges.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  each range in order to the output range.  Iterators increment for each
 *  range.  When the current element of one range is less than the other,
 *  that element is copied and the iterator advanced.  If an element is
 *  contained in both ranges, the element from the first range is copied and
 *  both ranges advance.  The output range may not overlap either input
 *  range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator>
  inline _OutputIterator
  set_union(_InputIterator1 __first1, _InputIterator1 __last1,
     _InputIterator2 __first2, _InputIterator2 __last2,
     _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set(__first1, __last1, __first2);
    __glibcxx_requires_sorted_set(__first2, __last2, __first1);
    __glibcxx_requires_irreflexive2(__first1, __last1);
    __glibcxx_requires_irreflexive2(__first2, __last2);

    return _GLIBCXX_STD_Astd::__set_union(__first1, __last1,
		__first2, __last2, __result,
		__gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Return the union of two sorted ranges using a comparison functor.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @param  __comp    The comparison functor.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  each range in order to the output range.  Iterators increment for each
 *  range.  When the current element of one range is less than the other
 *  according to @p __comp, that element is copied and the iterator advanced.
 *  If an equivalent element according to @p __comp is contained in both
 *  ranges, the element from the first range is copied and both ranges
 *  advance.  The output range may not overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  inline _OutputIterator
  set_union(_InputIterator1 __first1, _InputIterator1 __last1,
     _InputIterator2 __first2, _InputIterator2 __last2,
     _OutputIterator __result, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
    __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);

    return _GLIBCXX_STD_Astd::__set_union(__first1, __last1,
		__first2, __last2, __result,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator,
  typename _Compare>
  _OutputIterator
  __set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
       _InputIterator2 __first2, _InputIterator2 __last2,
       _OutputIterator __result, _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
if (__comp(__first1, __first2))
 ++__first1;
else if (__comp(__first2, __first1))
 ++__first2;
else
 {
   *__result = *__first1;
   ++__first1;
   ++__first2;
   ++__result;
 }
    return __result;
  }

/**
 *  @brief Return the intersection of two sorted ranges.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  both ranges in order to the output range.  Iterators increment for each
 *  range.  When the current element of one range is less than the other,
 *  that iterator advances.  If an element is contained in both ranges, the
 *  element from the first range is copied and both ranges advance.  The
 *  output range may not overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator>
  inline _OutputIterator
  set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
     _InputIterator2 __first2, _InputIterator2 __last2,
     _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set(__first1, __last1, __first2);
    __glibcxx_requires_sorted_set(__first2, __last2, __first1);
    __glibcxx_requires_irreflexive2(__first1, __last1);
    __glibcxx_requires_irreflexive2(__first2, __last2);

    return _GLIBCXX_STD_Astd::__set_intersection(__first1, __last1,
		     __first2, __last2, __result,
		     __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief Return the intersection of two sorted ranges using comparison
 *  functor.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @param  __comp    The comparison functor.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  both ranges in order to the output range.  Iterators increment for each
 *  range.  When the current element of one range is less than the other
 *  according to @p __comp, that iterator advances.  If an element is
 *  contained in both ranges according to @p __comp, the element from the
 *  first range is copied and both ranges advance.  The output range may not
 *  overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  inline _OutputIterator
  set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
     _InputIterator2 __first2, _InputIterator2 __last2,
     _OutputIterator __result, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
    __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);

    return _GLIBCXX_STD_Astd::__set_intersection(__first1, __last1,
		__first2, __last2, __result,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator,
  typename _Compare>
  _OutputIterator
  __set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
     _InputIterator2 __first2, _InputIterator2 __last2,
     _OutputIterator __result, _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
if (__comp(__first1, __first2))
 {
   *__result = *__first1;
   ++__first1;
   ++__result;
 }
else if (__comp(__first2, __first1))
 ++__first2;
else
 {
   ++__first1;
   ++__first2;
 }
    return std::copy(__first1, __last1, __result);
  }

/**
 *  @brief Return the difference of two sorted ranges.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  the first range but not the second in order to the output range.
 *  Iterators increment for each range.  When the current element of the
 *  first range is less than the second, that element is copied and the
 *  iterator advances.  If the current element of the second range is less,
 *  the iterator advances, but no element is copied.  If an element is
 *  contained in both ranges, no elements are copied and both ranges
 *  advance.  The output range may not overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator>
  inline _OutputIterator
  set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
   _InputIterator2 __first2, _InputIterator2 __last2,
   _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)	
    __glibcxx_requires_sorted_set(__first1, __last1, __first2);
    __glibcxx_requires_sorted_set(__first2, __last2, __first1);
    __glibcxx_requires_irreflexive2(__first1, __last1);
    __glibcxx_requires_irreflexive2(__first2, __last2);

    return _GLIBCXX_STD_Astd::__set_difference(__first1, __last1,
		   __first2, __last2, __result,
		   __gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Return the difference of two sorted ranges using comparison
 *  functor.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @param  __comp    The comparison functor.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  the first range but not the second in order to the output range.
 *  Iterators increment for each range.  When the current element of the
 *  first range is less than the second according to @p __comp, that element
 *  is copied and the iterator advances.  If the current element of the
 *  second range is less, no element is copied and the iterator advances.
 *  If an element is contained in both ranges according to @p __comp, no
 *  elements are copied and both ranges advance.  The output range may not
 *  overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  inline _OutputIterator
  set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
   _InputIterator2 __first2, _InputIterator2 __last2,
   _OutputIterator __result, _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
    __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);

    return _GLIBCXX_STD_Astd::__set_difference(__first1, __last1,
		   __first2, __last2, __result,
		   __gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator,
  typename _Compare>
  _OutputIterator
  __set_symmetric_difference(_InputIterator1 __first1,
	       _InputIterator1 __last1,
	       _InputIterator2 __first2,
	       _InputIterator2 __last2,
	       _OutputIterator __result,
	       _Compare __comp)
  {
    while (__first1 != __last1 && __first2 != __last2)
if (__comp(__first1, __first2))
 {
   *__result = *__first1;
   ++__first1;
   ++__result;
 }
else if (__comp(__first2, __first1))
 {
   *__result = *__first2;
   ++__first2;
   ++__result;
 }
else
 {
   ++__first1;
   ++__first2;
 }
    return std::copy(__first2, __last2, 
       std::copy(__first1, __last1, __result));
  }

/**
 *  @brief  Return the symmetric difference of two sorted ranges.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  one range but not the other in order to the output range.  Iterators
 *  increment for each range.  When the current element of one range is less
 *  than the other, that element is copied and the iterator advances.  If an
 *  element is contained in both ranges, no elements are copied and both
 *  ranges advance.  The output range may not overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator>
  inline _OutputIterator
  set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
	     _InputIterator2 __first2, _InputIterator2 __last2,
	     _OutputIterator __result)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_LessThanOpConcept<
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)	
    __glibcxx_requires_sorted_set(__first1, __last1, __first2);
    __glibcxx_requires_sorted_set(__first2, __last2, __first1);
    __glibcxx_requires_irreflexive2(__first1, __last1);
    __glibcxx_requires_irreflexive2(__first2, __last2);

    return _GLIBCXX_STD_Astd::__set_symmetric_difference(__first1, __last1,
			__first2, __last2, __result,
			__gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Return the symmetric difference of two sorted ranges using
 *  comparison functor.
 *  @ingroup set_algorithms
 *  @param  __first1  Start of first range.
 *  @param  __last1   End of first range.
 *  @param  __first2  Start of second range.
 *  @param  __last2   End of second range.
 *  @param  __comp    The comparison functor.
 *  @return  End of the output range.
 *  @ingroup set_algorithms
 *
 *  This operation iterates over both ranges, copying elements present in
 *  one range but not the other in order to the output range.  Iterators
 *  increment for each range.  When the current element of one range is less
 *  than the other according to @p comp, that element is copied and the
 *  iterator advances.  If an element is contained in both ranges according
 *  to @p __comp, no elements are copied and both ranges advance.  The output
 *  range may not overlap either input range.
*/
template<typename _InputIterator1, typename _InputIterator2,
  typename _OutputIterator, typename _Compare>
  inline _OutputIterator
  set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
	     _InputIterator2 __first2, _InputIterator2 __last2,
	     _OutputIterator __result,
	     _Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
    __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator1>::value_type,
   typename iterator_traits<_InputIterator2>::value_type>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_InputIterator2>::value_type,
   typename iterator_traits<_InputIterator1>::value_type>)
    __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
    __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
    __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);

    return _GLIBCXX_STD_Astd::__set_symmetric_difference(__first1, __last1,
		__first2, __last2, __result,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _ForwardIterator, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  _ForwardIterator
  __min_element(_ForwardIterator __first, _ForwardIterator __last,
  _Compare __comp)
  {
    if (__first == __last)
return __first;
    _ForwardIterator __result = __first;
    while (++__first != __last)
if (__comp(__first, __result))
 __result = __first;
    return __result;
  }

/**
 *  @brief  Return the minimum element in a range.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @return  Iterator referencing the first instance of the smallest value.
*/
template<typename _ForwardIterator>
  _GLIBCXX14_CONSTEXPRconstexpr
  _ForwardIterator
  inline min_element(_ForwardIterator __first, _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    return _GLIBCXX_STD_Astd::__min_element(__first, __last,
		__gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Return the minimum element in a range using comparison functor.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @param  __comp   Comparison functor.
 *  @return  Iterator referencing the first instance of the smallest value
 *  according to __comp.
*/
template<typename _ForwardIterator, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _ForwardIterator
  min_element(_ForwardIterator __first, _ForwardIterator __last,
_Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_ForwardIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    return _GLIBCXX_STD_Astd::__min_element(__first, __last,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

template<typename _ForwardIterator, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  _ForwardIterator
  __max_element(_ForwardIterator __first, _ForwardIterator __last,
  _Compare __comp)
  {
    if (__first == __last) return __first;
    _ForwardIterator __result = __first;
    while (++__first != __last)
if (__comp(__result, __first))
 __result = __first;
    return __result;
  }

/**
 *  @brief  Return the maximum element in a range.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @return  Iterator referencing the first instance of the largest value.
*/
template<typename _ForwardIterator>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _ForwardIterator
  max_element(_ForwardIterator __first, _ForwardIterator __last)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_LessThanComparableConcept<
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive(__first, __last);

    return _GLIBCXX_STD_Astd::__max_element(__first, __last,
		__gnu_cxx::__ops::__iter_less_iter());
  }

/**
 *  @brief  Return the maximum element in a range using comparison functor.
 *  @ingroup sorting_algorithms
 *  @param  __first  Start of range.
 *  @param  __last   End of range.
 *  @param  __comp   Comparison functor.
 *  @return  Iterator referencing the first instance of the largest value
 *  according to __comp.
*/
template<typename _ForwardIterator, typename _Compare>
  _GLIBCXX14_CONSTEXPRconstexpr
  inline _ForwardIterator
  max_element(_ForwardIterator __first, _ForwardIterator __last,
_Compare __comp)
  {
    // concept requirements
    __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
    __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
   typename iterator_traits<_ForwardIterator>::value_type,
   typename iterator_traits<_ForwardIterator>::value_type>)
    __glibcxx_requires_valid_range(__first, __last);
    __glibcxx_requires_irreflexive_pred(__first, __last, __comp);

    return _GLIBCXX_STD_Astd::__max_element(__first, __last,
		__gnu_cxx::__ops::__iter_comp_iter(__comp));
  }

5579_GLIBCXX_END_NAMESPACE_ALGO
5580} // namespace std

5582#endif /* _STL_ALGO_H */

←

/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/ilist_iterator.h

1//===- llvm/ADT/ilist_iterator.h - Intrusive List Iterator ------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//

9#ifndef LLVM_ADT_ILIST_ITERATOR_H
10#define LLVM_ADT_ILIST_ITERATOR_H

12#include "llvm/ADT/ilist_node.h"
13#include <cassert>
14#include <cstddef>
15#include <iterator>
16#include <type_traits>

18namespace llvm {

20namespace ilist_detail {

22/// Find const-correct node types.
23template <class OptionsT, bool IsConst> struct IteratorTraits;
24template <class OptionsT> struct IteratorTraits<OptionsT, false> {
using value_type = typename OptionsT::value_type;
using pointer = typename OptionsT::pointer;
using reference = typename OptionsT::reference;
using node_pointer = ilist_node_impl<OptionsT> *;
using node_reference = ilist_node_impl<OptionsT> &;
30};
31template <class OptionsT> struct IteratorTraits<OptionsT, true> {
using value_type = const typename OptionsT::value_type;
using pointer = typename OptionsT::const_pointer;
using reference = typename OptionsT::const_reference;
using node_pointer = const ilist_node_impl<OptionsT> *;
using node_reference = const ilist_node_impl<OptionsT> &;
37};

39template <bool IsReverse> struct IteratorHelper;
40template <> struct IteratorHelper<false> : ilist_detail::NodeAccess {
using Access = ilist_detail::NodeAccess;

template <class T> static void increment(T *&I) { I = Access::getNext(*I); }
template <class T> static void decrement(T *&I) { I = Access::getPrev(*I); }
45};
46template <> struct IteratorHelper<true> : ilist_detail::NodeAccess {
using Access = ilist_detail::NodeAccess;

template <class T> static void increment(T *&I) { I = Access::getPrev(*I); }
template <class T> static void decrement(T *&I) { I = Access::getNext(*I); }
51};

53} // end namespace ilist_detail

55/// Iterator for intrusive lists  based on ilist_node.
56template <class OptionsT, bool IsReverse, bool IsConst>
57class ilist_iterator : ilist_detail::SpecificNodeAccess<OptionsT> {
friend ilist_iterator<OptionsT, IsReverse, !IsConst>;
friend ilist_iterator<OptionsT, !IsReverse, IsConst>;
friend ilist_iterator<OptionsT, !IsReverse, !IsConst>;

using Traits = ilist_detail::IteratorTraits<OptionsT, IsConst>;
using Access = ilist_detail::SpecificNodeAccess<OptionsT>;

65public:
using value_type = typename Traits::value_type;
using pointer = typename Traits::pointer;
using reference = typename Traits::reference;
using difference_type = ptrdiff_t;
using iterator_category = std::bidirectional_iterator_tag;
using const_pointer = typename OptionsT::const_pointer;
using const_reference = typename OptionsT::const_reference;

74private:
using node_pointer = typename Traits::node_pointer;
using node_reference = typename Traits::node_reference;

node_pointer NodePtr = nullptr;

80public:
/// Create from an ilist_node.
explicit ilist_iterator(node_reference N) : NodePtr(&N) {}

explicit ilist_iterator(pointer NP) : NodePtr(Access::getNodePtr(NP)) {}
explicit ilist_iterator(reference NR) : NodePtr(Access::getNodePtr(&NR)) {}
ilist_iterator() = default;

// This is templated so that we can allow constructing a const iterator from
// a nonconst iterator...
template <bool RHSIsConst>
ilist_iterator(const ilist_iterator<OptionsT, IsReverse, RHSIsConst> &RHS,
               std::enable_if_t<IsConst || !RHSIsConst, void *> = nullptr)
    : NodePtr(RHS.NodePtr) {}

// This is templated so that we can allow assigning to a const iterator from
// a nonconst iterator...
template <bool RHSIsConst>
std::enable_if_t<IsConst || !RHSIsConst, ilist_iterator &>
operator=(const ilist_iterator<OptionsT, IsReverse, RHSIsConst> &RHS) {
  NodePtr = RHS.NodePtr;
  return *this;
}

/// Explicit conversion between forward/reverse iterators.
///
/// Translate between forward and reverse iterators without changing range
/// boundaries.  The resulting iterator will dereference (and have a handle)
/// to the previous node, which is somewhat unexpected; but converting the
/// two endpoints in a range will give the same range in reverse.
///
/// This matches std::reverse_iterator conversions.
explicit ilist_iterator(
    const ilist_iterator<OptionsT, !IsReverse, IsConst> &RHS)
    : ilist_iterator(++RHS.getReverse()) {}

/// Get a reverse iterator to the same node.
///
/// Gives a reverse iterator that will dereference (and have a handle) to the
/// same node.  Converting the endpoint iterators in a range will give a
/// different range; for range operations, use the explicit conversions.
ilist_iterator<OptionsT, !IsReverse, IsConst> getReverse() const {
  if (NodePtr)
    return ilist_iterator<OptionsT, !IsReverse, IsConst>(*NodePtr);
  return ilist_iterator<OptionsT, !IsReverse, IsConst>();
}

/// Const-cast.
ilist_iterator<OptionsT, IsReverse, false> getNonConst() const {
  if (NodePtr)
    return ilist_iterator<OptionsT, IsReverse, false>(
        const_cast<typename ilist_iterator<OptionsT, IsReverse,
                                           false>::node_reference>(*NodePtr));
  return ilist_iterator<OptionsT, IsReverse, false>();
}

// Accessors...
reference operator*() const {
  assert(!NodePtr->isKnownSentinel())((!NodePtr->isKnownSentinel()) ? static_cast<void> (
0) : __assert_fail ("!NodePtr->isKnownSentinel()", "/build/llvm-toolchain-snapshot-12~++20210121111113+bee486851c1a/llvm/include/llvm/ADT/ilist_iterator.h"
, 138, __PRETTY_FUNCTION__));
  return *Access::getValuePtr(NodePtr);
}
pointer operator->() const { return &operator*(); }

// Comparison operators
friend bool operator==(const ilist_iterator &LHS, const ilist_iterator &RHS) {
  return LHS.NodePtr24.1
'LHS.NodePtr' is equal to 'RHS.NodePtr'
1
'LHS.NodePtr' is equal to 'RHS.NodePtr'
1
'LHS.NodePtr' is equal to 'RHS.NodePtr'
1
'LHS.NodePtr' is equal to 'RHS.NodePtr'
1
'LHS.NodePtr' is equal to 'RHS.NodePtr'
1
'LHS.NodePtr' is equal to 'RHS.NodePtr'
 == RHS.NodePtr;
25
←
Returning the value 1, which participates in a condition later→
}
friend bool operator!=(const ilist_iterator &LHS, const ilist_iterator &RHS) {
  return LHS.NodePtr != RHS.NodePtr;
}

// Increment and decrement operators...
ilist_iterator &operator--() {
  NodePtr = IsReverse ? NodePtr->getNext() : NodePtr->getPrev();
  return *this;
}
ilist_iterator &operator++() {
  NodePtr = IsReverse ? NodePtr->getPrev() : NodePtr->getNext();
  return *this;
}
ilist_iterator operator--(int) {
  ilist_iterator tmp = *this;
  --*this;
  return tmp;
}
ilist_iterator operator++(int) {
  ilist_iterator tmp = *this;
  ++*this;
  return tmp;
}

/// Get the underlying ilist_node.
node_pointer getNodePtr() const { return static_cast<node_pointer>(NodePtr); }

/// Check for end.  Only valid if ilist_sentinel_tracking<true>.
bool isEnd() const { return NodePtr ? NodePtr->isSentinel() : false; }
176};

178template <typename From> struct simplify_type;

180/// Allow ilist_iterators to convert into pointers to a node automatically when
181/// used by the dyn_cast, cast, isa mechanisms...
182///
183/// FIXME: remove this, since there is no implicit conversion to NodeTy.
184template <class OptionsT, bool IsConst>
185struct simplify_type<ilist_iterator<OptionsT, false, IsConst>> {
using iterator = ilist_iterator<OptionsT, false, IsConst>;
using SimpleType = typename iterator::pointer;

static SimpleType getSimplifiedValue(const iterator &Node) { return &*Node; }
190};
191template <class OptionsT, bool IsConst>
192struct simplify_type<const ilist_iterator<OptionsT, false, IsConst>>
  : simplify_type<ilist_iterator<OptionsT, false, IsConst>> {};

195} // end namespace llvm

197#endif // LLVM_ADT_ILIST_ITERATOR_H