LCOV - code coverage report
Current view: top level - lib/CodeGen - CodeGenPrepare.cpp (source / functions) Hit Total Coverage
Test: llvm-toolchain.info Lines: 1688 2060 81.9 %
Date: 2018-10-20 13:21:21 Functions: 108 136 79.4 %
Legend: Lines: hit not hit

          Line data    Source code
       1             : //===- CodeGenPrepare.cpp - Prepare a function for code generation --------===//
       2             : //
       3             : //                     The LLVM Compiler Infrastructure
       4             : //
       5             : // This file is distributed under the University of Illinois Open Source
       6             : // License. See LICENSE.TXT for details.
       7             : //
       8             : //===----------------------------------------------------------------------===//
       9             : //
      10             : // This pass munges the code in the input function to better prepare it for
      11             : // SelectionDAG-based code generation. This works around limitations in it's
      12             : // basic-block-at-a-time approach. It should eventually be removed.
      13             : //
      14             : //===----------------------------------------------------------------------===//
      15             : 
      16             : #include "llvm/ADT/APInt.h"
      17             : #include "llvm/ADT/ArrayRef.h"
      18             : #include "llvm/ADT/DenseMap.h"
      19             : #include "llvm/ADT/PointerIntPair.h"
      20             : #include "llvm/ADT/STLExtras.h"
      21             : #include "llvm/ADT/SmallPtrSet.h"
      22             : #include "llvm/ADT/SmallVector.h"
      23             : #include "llvm/ADT/Statistic.h"
      24             : #include "llvm/Analysis/BlockFrequencyInfo.h"
      25             : #include "llvm/Analysis/BranchProbabilityInfo.h"
      26             : #include "llvm/Analysis/ConstantFolding.h"
      27             : #include "llvm/Analysis/InstructionSimplify.h"
      28             : #include "llvm/Analysis/LoopInfo.h"
      29             : #include "llvm/Analysis/MemoryBuiltins.h"
      30             : #include "llvm/Analysis/ProfileSummaryInfo.h"
      31             : #include "llvm/Analysis/TargetLibraryInfo.h"
      32             : #include "llvm/Analysis/TargetTransformInfo.h"
      33             : #include "llvm/Transforms/Utils/Local.h"
      34             : #include "llvm/Analysis/ValueTracking.h"
      35             : #include "llvm/CodeGen/Analysis.h"
      36             : #include "llvm/CodeGen/ISDOpcodes.h"
      37             : #include "llvm/CodeGen/SelectionDAGNodes.h"
      38             : #include "llvm/CodeGen/TargetLowering.h"
      39             : #include "llvm/CodeGen/TargetPassConfig.h"
      40             : #include "llvm/CodeGen/TargetSubtargetInfo.h"
      41             : #include "llvm/CodeGen/ValueTypes.h"
      42             : #include "llvm/Config/llvm-config.h"
      43             : #include "llvm/IR/Argument.h"
      44             : #include "llvm/IR/Attributes.h"
      45             : #include "llvm/IR/BasicBlock.h"
      46             : #include "llvm/IR/CallSite.h"
      47             : #include "llvm/IR/Constant.h"
      48             : #include "llvm/IR/Constants.h"
      49             : #include "llvm/IR/DataLayout.h"
      50             : #include "llvm/IR/DerivedTypes.h"
      51             : #include "llvm/IR/Dominators.h"
      52             : #include "llvm/IR/Function.h"
      53             : #include "llvm/IR/GetElementPtrTypeIterator.h"
      54             : #include "llvm/IR/GlobalValue.h"
      55             : #include "llvm/IR/GlobalVariable.h"
      56             : #include "llvm/IR/IRBuilder.h"
      57             : #include "llvm/IR/InlineAsm.h"
      58             : #include "llvm/IR/InstrTypes.h"
      59             : #include "llvm/IR/Instruction.h"
      60             : #include "llvm/IR/Instructions.h"
      61             : #include "llvm/IR/IntrinsicInst.h"
      62             : #include "llvm/IR/Intrinsics.h"
      63             : #include "llvm/IR/LLVMContext.h"
      64             : #include "llvm/IR/MDBuilder.h"
      65             : #include "llvm/IR/Module.h"
      66             : #include "llvm/IR/Operator.h"
      67             : #include "llvm/IR/PatternMatch.h"
      68             : #include "llvm/IR/Statepoint.h"
      69             : #include "llvm/IR/Type.h"
      70             : #include "llvm/IR/Use.h"
      71             : #include "llvm/IR/User.h"
      72             : #include "llvm/IR/Value.h"
      73             : #include "llvm/IR/ValueHandle.h"
      74             : #include "llvm/IR/ValueMap.h"
      75             : #include "llvm/Pass.h"
      76             : #include "llvm/Support/BlockFrequency.h"
      77             : #include "llvm/Support/BranchProbability.h"
      78             : #include "llvm/Support/Casting.h"
      79             : #include "llvm/Support/CommandLine.h"
      80             : #include "llvm/Support/Compiler.h"
      81             : #include "llvm/Support/Debug.h"
      82             : #include "llvm/Support/ErrorHandling.h"
      83             : #include "llvm/Support/MachineValueType.h"
      84             : #include "llvm/Support/MathExtras.h"
      85             : #include "llvm/Support/raw_ostream.h"
      86             : #include "llvm/Target/TargetMachine.h"
      87             : #include "llvm/Target/TargetOptions.h"
      88             : #include "llvm/Transforms/Utils/BasicBlockUtils.h"
      89             : #include "llvm/Transforms/Utils/BypassSlowDivision.h"
      90             : #include "llvm/Transforms/Utils/SimplifyLibCalls.h"
      91             : #include <algorithm>
      92             : #include <cassert>
      93             : #include <cstdint>
      94             : #include <iterator>
      95             : #include <limits>
      96             : #include <memory>
      97             : #include <utility>
      98             : #include <vector>
      99             : 
     100             : using namespace llvm;
     101             : using namespace llvm::PatternMatch;
     102             : 
     103             : #define DEBUG_TYPE "codegenprepare"
     104             : 
     105             : STATISTIC(NumBlocksElim, "Number of blocks eliminated");
     106             : STATISTIC(NumPHIsElim,   "Number of trivial PHIs eliminated");
     107             : STATISTIC(NumGEPsElim,   "Number of GEPs converted to casts");
     108             : STATISTIC(NumCmpUses, "Number of uses of Cmp expressions replaced with uses of "
     109             :                       "sunken Cmps");
     110             : STATISTIC(NumCastUses, "Number of uses of Cast expressions replaced with uses "
     111             :                        "of sunken Casts");
     112             : STATISTIC(NumMemoryInsts, "Number of memory instructions whose address "
     113             :                           "computations were sunk");
     114             : STATISTIC(NumMemoryInstsPhiCreated,
     115             :           "Number of phis created when address "
     116             :           "computations were sunk to memory instructions");
     117             : STATISTIC(NumMemoryInstsSelectCreated,
     118             :           "Number of select created when address "
     119             :           "computations were sunk to memory instructions");
     120             : STATISTIC(NumExtsMoved,  "Number of [s|z]ext instructions combined with loads");
     121             : STATISTIC(NumExtUses,    "Number of uses of [s|z]ext instructions optimized");
     122             : STATISTIC(NumAndsAdded,
     123             :           "Number of and mask instructions added to form ext loads");
     124             : STATISTIC(NumAndUses, "Number of uses of and mask instructions optimized");
     125             : STATISTIC(NumRetsDup,    "Number of return instructions duplicated");
     126             : STATISTIC(NumDbgValueMoved, "Number of debug value instructions moved");
     127             : STATISTIC(NumSelectsExpanded, "Number of selects turned into branches");
     128             : STATISTIC(NumStoreExtractExposed, "Number of store(extractelement) exposed");
     129             : 
     130             : static cl::opt<bool> DisableBranchOpts(
     131             :   "disable-cgp-branch-opts", cl::Hidden, cl::init(false),
     132             :   cl::desc("Disable branch optimizations in CodeGenPrepare"));
     133             : 
     134             : static cl::opt<bool>
     135             :     DisableGCOpts("disable-cgp-gc-opts", cl::Hidden, cl::init(false),
     136             :                   cl::desc("Disable GC optimizations in CodeGenPrepare"));
     137             : 
     138             : static cl::opt<bool> DisableSelectToBranch(
     139             :   "disable-cgp-select2branch", cl::Hidden, cl::init(false),
     140             :   cl::desc("Disable select to branch conversion."));
     141             : 
     142             : static cl::opt<bool> AddrSinkUsingGEPs(
     143             :   "addr-sink-using-gep", cl::Hidden, cl::init(true),
     144             :   cl::desc("Address sinking in CGP using GEPs."));
     145             : 
     146             : static cl::opt<bool> EnableAndCmpSinking(
     147             :    "enable-andcmp-sinking", cl::Hidden, cl::init(true),
     148             :    cl::desc("Enable sinkinig and/cmp into branches."));
     149             : 
     150             : static cl::opt<bool> DisableStoreExtract(
     151             :     "disable-cgp-store-extract", cl::Hidden, cl::init(false),
     152             :     cl::desc("Disable store(extract) optimizations in CodeGenPrepare"));
     153             : 
     154             : static cl::opt<bool> StressStoreExtract(
     155             :     "stress-cgp-store-extract", cl::Hidden, cl::init(false),
     156             :     cl::desc("Stress test store(extract) optimizations in CodeGenPrepare"));
     157             : 
     158             : static cl::opt<bool> DisableExtLdPromotion(
     159             :     "disable-cgp-ext-ld-promotion", cl::Hidden, cl::init(false),
     160             :     cl::desc("Disable ext(promotable(ld)) -> promoted(ext(ld)) optimization in "
     161             :              "CodeGenPrepare"));
     162             : 
     163             : static cl::opt<bool> StressExtLdPromotion(
     164             :     "stress-cgp-ext-ld-promotion", cl::Hidden, cl::init(false),
     165             :     cl::desc("Stress test ext(promotable(ld)) -> promoted(ext(ld)) "
     166             :              "optimization in CodeGenPrepare"));
     167             : 
     168             : static cl::opt<bool> DisablePreheaderProtect(
     169             :     "disable-preheader-prot", cl::Hidden, cl::init(false),
     170             :     cl::desc("Disable protection against removing loop preheaders"));
     171             : 
     172             : static cl::opt<bool> ProfileGuidedSectionPrefix(
     173             :     "profile-guided-section-prefix", cl::Hidden, cl::init(true), cl::ZeroOrMore,
     174             :     cl::desc("Use profile info to add section prefix for hot/cold functions"));
     175             : 
     176             : static cl::opt<unsigned> FreqRatioToSkipMerge(
     177             :     "cgp-freq-ratio-to-skip-merge", cl::Hidden, cl::init(2),
     178             :     cl::desc("Skip merging empty blocks if (frequency of empty block) / "
     179             :              "(frequency of destination block) is greater than this ratio"));
     180             : 
     181             : static cl::opt<bool> ForceSplitStore(
     182             :     "force-split-store", cl::Hidden, cl::init(false),
     183             :     cl::desc("Force store splitting no matter what the target query says."));
     184             : 
     185             : static cl::opt<bool>
     186             : EnableTypePromotionMerge("cgp-type-promotion-merge", cl::Hidden,
     187             :     cl::desc("Enable merging of redundant sexts when one is dominating"
     188             :     " the other."), cl::init(true));
     189             : 
     190             : static cl::opt<bool> DisableComplexAddrModes(
     191             :     "disable-complex-addr-modes", cl::Hidden, cl::init(false),
     192             :     cl::desc("Disables combining addressing modes with different parts "
     193             :              "in optimizeMemoryInst."));
     194             : 
     195             : static cl::opt<bool>
     196             : AddrSinkNewPhis("addr-sink-new-phis", cl::Hidden, cl::init(false),
     197             :                 cl::desc("Allow creation of Phis in Address sinking."));
     198             : 
     199             : static cl::opt<bool>
     200             : AddrSinkNewSelects("addr-sink-new-select", cl::Hidden, cl::init(true),
     201             :                    cl::desc("Allow creation of selects in Address sinking."));
     202             : 
     203             : static cl::opt<bool> AddrSinkCombineBaseReg(
     204             :     "addr-sink-combine-base-reg", cl::Hidden, cl::init(true),
     205             :     cl::desc("Allow combining of BaseReg field in Address sinking."));
     206             : 
     207             : static cl::opt<bool> AddrSinkCombineBaseGV(
     208             :     "addr-sink-combine-base-gv", cl::Hidden, cl::init(true),
     209             :     cl::desc("Allow combining of BaseGV field in Address sinking."));
     210             : 
     211             : static cl::opt<bool> AddrSinkCombineBaseOffs(
     212             :     "addr-sink-combine-base-offs", cl::Hidden, cl::init(true),
     213             :     cl::desc("Allow combining of BaseOffs field in Address sinking."));
     214             : 
     215             : static cl::opt<bool> AddrSinkCombineScaledReg(
     216             :     "addr-sink-combine-scaled-reg", cl::Hidden, cl::init(true),
     217             :     cl::desc("Allow combining of ScaledReg field in Address sinking."));
     218             : 
     219             : static cl::opt<bool>
     220             :     EnableGEPOffsetSplit("cgp-split-large-offset-gep", cl::Hidden,
     221             :                          cl::init(true),
     222             :                          cl::desc("Enable splitting large offset of GEP."));
     223             : 
     224             : namespace {
     225             : 
     226             : enum ExtType {
     227             :   ZeroExtension,   // Zero extension has been seen.
     228             :   SignExtension,   // Sign extension has been seen.
     229             :   BothExtension    // This extension type is used if we saw sext after
     230             :                    // ZeroExtension had been set, or if we saw zext after
     231             :                    // SignExtension had been set. It makes the type
     232             :                    // information of a promoted instruction invalid.
     233             : };
     234             : 
     235             : using SetOfInstrs = SmallPtrSet<Instruction *, 16>;
     236             : using TypeIsSExt = PointerIntPair<Type *, 2, ExtType>;
     237             : using InstrToOrigTy = DenseMap<Instruction *, TypeIsSExt>;
     238             : using SExts = SmallVector<Instruction *, 16>;
     239             : using ValueToSExts = DenseMap<Value *, SExts>;
     240             : 
     241             : class TypePromotionTransaction;
     242             : 
     243             :   class CodeGenPrepare : public FunctionPass {
     244             :     const TargetMachine *TM = nullptr;
     245             :     const TargetSubtargetInfo *SubtargetInfo;
     246             :     const TargetLowering *TLI = nullptr;
     247             :     const TargetRegisterInfo *TRI;
     248             :     const TargetTransformInfo *TTI = nullptr;
     249             :     const TargetLibraryInfo *TLInfo;
     250             :     const LoopInfo *LI;
     251             :     std::unique_ptr<BlockFrequencyInfo> BFI;
     252             :     std::unique_ptr<BranchProbabilityInfo> BPI;
     253             : 
     254             :     /// As we scan instructions optimizing them, this is the next instruction
     255             :     /// to optimize. Transforms that can invalidate this should update it.
     256             :     BasicBlock::iterator CurInstIterator;
     257             : 
     258             :     /// Keeps track of non-local addresses that have been sunk into a block.
     259             :     /// This allows us to avoid inserting duplicate code for blocks with
     260             :     /// multiple load/stores of the same address. The usage of WeakTrackingVH
     261             :     /// enables SunkAddrs to be treated as a cache whose entries can be
     262             :     /// invalidated if a sunken address computation has been erased.
     263             :     ValueMap<Value*, WeakTrackingVH> SunkAddrs;
     264             : 
     265             :     /// Keeps track of all instructions inserted for the current function.
     266             :     SetOfInstrs InsertedInsts;
     267             : 
     268             :     /// Keeps track of the type of the related instruction before their
     269             :     /// promotion for the current function.
     270             :     InstrToOrigTy PromotedInsts;
     271             : 
     272             :     /// Keep track of instructions removed during promotion.
     273             :     SetOfInstrs RemovedInsts;
     274             : 
     275             :     /// Keep track of sext chains based on their initial value.
     276             :     DenseMap<Value *, Instruction *> SeenChainsForSExt;
     277             : 
     278             :     /// Keep track of GEPs accessing the same data structures such as structs or
     279             :     /// arrays that are candidates to be split later because of their large
     280             :     /// size.
     281             :     MapVector<
     282             :         AssertingVH<Value>,
     283             :         SmallVector<std::pair<AssertingVH<GetElementPtrInst>, int64_t>, 32>>
     284             :         LargeOffsetGEPMap;
     285             : 
     286             :     /// Keep track of new GEP base after splitting the GEPs having large offset.
     287             :     SmallSet<AssertingVH<Value>, 2> NewGEPBases;
     288             : 
     289             :     /// Map serial numbers to Large offset GEPs.
     290             :     DenseMap<AssertingVH<GetElementPtrInst>, int> LargeOffsetGEPID;
     291             : 
     292             :     /// Keep track of SExt promoted.
     293             :     ValueToSExts ValToSExtendedUses;
     294             : 
     295             :     /// True if CFG is modified in any way.
     296             :     bool ModifiedDT;
     297             : 
     298             :     /// True if optimizing for size.
     299             :     bool OptSize;
     300             : 
     301             :     /// DataLayout for the Function being processed.
     302             :     const DataLayout *DL = nullptr;
     303             : 
     304             :   public:
     305             :     static char ID; // Pass identification, replacement for typeid
     306             : 
     307       60894 :     CodeGenPrepare() : FunctionPass(ID) {
     308       20298 :       initializeCodeGenPreparePass(*PassRegistry::getPassRegistry());
     309       20298 :     }
     310             : 
     311             :     bool runOnFunction(Function &F) override;
     312             : 
     313          31 :     StringRef getPassName() const override { return "CodeGen Prepare"; }
     314             : 
     315       20165 :     void getAnalysisUsage(AnalysisUsage &AU) const override {
     316             :       // FIXME: When we can selectively preserve passes, preserve the domtree.
     317             :       AU.addRequired<ProfileSummaryInfoWrapperPass>();
     318             :       AU.addRequired<TargetLibraryInfoWrapperPass>();
     319             :       AU.addRequired<TargetTransformInfoWrapperPass>();
     320             :       AU.addRequired<LoopInfoWrapperPass>();
     321       20165 :     }
     322             : 
     323             :   private:
     324             :     bool eliminateFallThrough(Function &F);
     325             :     bool eliminateMostlyEmptyBlocks(Function &F);
     326             :     BasicBlock *findDestBlockOfMergeableEmptyBlock(BasicBlock *BB);
     327             :     bool canMergeBlocks(const BasicBlock *BB, const BasicBlock *DestBB) const;
     328             :     void eliminateMostlyEmptyBlock(BasicBlock *BB);
     329             :     bool isMergingEmptyBlockProfitable(BasicBlock *BB, BasicBlock *DestBB,
     330             :                                        bool isPreheader);
     331             :     bool optimizeBlock(BasicBlock &BB, bool &ModifiedDT);
     332             :     bool optimizeInst(Instruction *I, bool &ModifiedDT);
     333             :     bool optimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
     334             :                             Type *AccessTy, unsigned AddrSpace);
     335             :     bool optimizeInlineAsmInst(CallInst *CS);
     336             :     bool optimizeCallInst(CallInst *CI, bool &ModifiedDT);
     337             :     bool optimizeExt(Instruction *&I);
     338             :     bool optimizeExtUses(Instruction *I);
     339             :     bool optimizeLoadExt(LoadInst *Load);
     340             :     bool optimizeSelectInst(SelectInst *SI);
     341             :     bool optimizeShuffleVectorInst(ShuffleVectorInst *SVI);
     342             :     bool optimizeSwitchInst(SwitchInst *SI);
     343             :     bool optimizeExtractElementInst(Instruction *Inst);
     344             :     bool dupRetToEnableTailCallOpts(BasicBlock *BB);
     345             :     bool placeDbgValues(Function &F);
     346             :     bool canFormExtLd(const SmallVectorImpl<Instruction *> &MovedExts,
     347             :                       LoadInst *&LI, Instruction *&Inst, bool HasPromoted);
     348             :     bool tryToPromoteExts(TypePromotionTransaction &TPT,
     349             :                           const SmallVectorImpl<Instruction *> &Exts,
     350             :                           SmallVectorImpl<Instruction *> &ProfitablyMovedExts,
     351             :                           unsigned CreatedInstsCost = 0);
     352             :     bool mergeSExts(Function &F);
     353             :     bool splitLargeGEPOffsets();
     354             :     bool performAddressTypePromotion(
     355             :         Instruction *&Inst,
     356             :         bool AllowPromotionWithoutCommonHeader,
     357             :         bool HasPromoted, TypePromotionTransaction &TPT,
     358             :         SmallVectorImpl<Instruction *> &SpeculativelyMovedExts);
     359             :     bool splitBranchCondition(Function &F);
     360             :     bool simplifyOffsetableRelocate(Instruction &I);
     361             :   };
     362             : 
     363             : } // end anonymous namespace
     364             : 
     365             : char CodeGenPrepare::ID = 0;
     366             : 
     367       39044 : INITIALIZE_PASS_BEGIN(CodeGenPrepare, DEBUG_TYPE,
     368             :                       "Optimize for code generation", false, false)
     369       39044 : INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)
     370      123448 : INITIALIZE_PASS_END(CodeGenPrepare, DEBUG_TYPE,
     371             :                     "Optimize for code generation", false, false)
     372             : 
     373       20202 : FunctionPass *llvm::createCodeGenPreparePass() { return new CodeGenPrepare(); }
     374             : 
     375      198715 : bool CodeGenPrepare::runOnFunction(Function &F) {
     376      198715 :   if (skipFunction(F))
     377             :     return false;
     378             : 
     379      198528 :   DL = &F.getParent()->getDataLayout();
     380             : 
     381             :   bool EverMadeChange = false;
     382             :   // Clear per function information.
     383      198528 :   InsertedInsts.clear();
     384      198528 :   PromotedInsts.clear();
     385             : 
     386      198528 :   ModifiedDT = false;
     387      198528 :   if (auto *TPC = getAnalysisIfAvailable<TargetPassConfig>()) {
     388      198518 :     TM = &TPC->getTM<TargetMachine>();
     389      198518 :     SubtargetInfo = TM->getSubtargetImpl(F);
     390      198518 :     TLI = SubtargetInfo->getTargetLowering();
     391      198518 :     TRI = SubtargetInfo->getRegisterInfo();
     392             :   }
     393      198528 :   TLInfo = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
     394      198528 :   TTI = &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
     395      198528 :   LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
     396      198528 :   BPI.reset(new BranchProbabilityInfo(F, *LI));
     397      198528 :   BFI.reset(new BlockFrequencyInfo(F, *BPI, *LI));
     398      198528 :   OptSize = F.optForSize();
     399             : 
     400             :   ProfileSummaryInfo *PSI =
     401      198528 :       getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
     402      198528 :   if (ProfileGuidedSectionPrefix) {
     403      198528 :     if (PSI->isFunctionHotInCallGraph(&F, *BFI))
     404          13 :       F.setSectionPrefix(".hot");
     405      198515 :     else if (PSI->isFunctionColdInCallGraph(&F, *BFI))
     406           6 :       F.setSectionPrefix(".unlikely");
     407             :   }
     408             : 
     409             :   /// This optimization identifies DIV instructions that can be
     410             :   /// profitably bypassed and carried out with a shorter, faster divide.
     411      198528 :   if (!OptSize && !PSI->hasHugeWorkingSetSize() && TLI &&
     412             :       TLI->isSlowDivBypassed()) {
     413             :     const DenseMap<unsigned int, unsigned int> &BypassWidths =
     414             :        TLI->getBypassSlowDivWidths();
     415             :     BasicBlock* BB = &*F.begin();
     416       23763 :     while (BB != nullptr) {
     417             :       // bypassSlowDivision may create new BBs, but we don't want to reapply the
     418             :       // optimization to those blocks.
     419             :       BasicBlock* Next = BB->getNextNode();
     420       12301 :       EverMadeChange |= bypassSlowDivision(BB, BypassWidths);
     421             :       BB = Next;
     422             :     }
     423             :   }
     424             : 
     425             :   // Eliminate blocks that contain only PHI nodes and an
     426             :   // unconditional branch.
     427      198528 :   EverMadeChange |= eliminateMostlyEmptyBlocks(F);
     428             : 
     429      198528 :   if (!DisableBranchOpts)
     430      198465 :     EverMadeChange |= splitBranchCondition(F);
     431             : 
     432             :   // Split some critical edges where one of the sources is an indirect branch,
     433             :   // to help generate sane code for PHIs involving such edges.
     434      198528 :   EverMadeChange |= SplitIndirectBrCriticalEdges(F);
     435             : 
     436             :   bool MadeChange = true;
     437      408828 :   while (MadeChange) {
     438             :     MadeChange = false;
     439      210300 :     SeenChainsForSExt.clear();
     440      210300 :     ValToSExtendedUses.clear();
     441      210300 :     RemovedInsts.clear();
     442             :     LargeOffsetGEPMap.clear();
     443      210300 :     LargeOffsetGEPID.clear();
     444      850560 :     for (Function::iterator I = F.begin(); I != F.end(); ) {
     445             :       BasicBlock *BB = &*I++;
     446      640297 :       bool ModifiedDTOnIteration = false;
     447      640297 :       MadeChange |= optimizeBlock(*BB, ModifiedDTOnIteration);
     448             : 
     449             :       // Restart BB iteration if the dominator tree of the Function was changed
     450      640297 :       if (ModifiedDTOnIteration)
     451             :         break;
     452             :     }
     453      210300 :     if (EnableTypePromotionMerge && !ValToSExtendedUses.empty())
     454          36 :       MadeChange |= mergeSExts(F);
     455      210300 :     if (!LargeOffsetGEPMap.empty())
     456          11 :       MadeChange |= splitLargeGEPOffsets();
     457             : 
     458             :     // Really free removed instructions during promotion.
     459      210688 :     for (Instruction *I : RemovedInsts)
     460         388 :       I->deleteValue();
     461             : 
     462      210300 :     EverMadeChange |= MadeChange;
     463             :   }
     464             : 
     465             :   SunkAddrs.clear();
     466             : 
     467      198528 :   if (!DisableBranchOpts) {
     468             :     MadeChange = false;
     469             :     // Use a set vector to get deterministic iteration order. The order the
     470             :     // blocks are removed may affect whether or not PHI nodes in successors
     471             :     // are removed.
     472             :     SmallSetVector<BasicBlock*, 8> WorkList;
     473      617057 :     for (BasicBlock &BB : F) {
     474      418592 :       SmallVector<BasicBlock *, 2> Successors(succ_begin(&BB), succ_end(&BB));
     475      418592 :       MadeChange |= ConstantFoldTerminator(&BB, true);
     476      418592 :       if (!MadeChange) continue;
     477             : 
     478        7281 :       for (SmallVectorImpl<BasicBlock*>::iterator
     479       11842 :              II = Successors.begin(), IE = Successors.end(); II != IE; ++II)
     480        7281 :         if (pred_begin(*II) == pred_end(*II))
     481        1080 :           WorkList.insert(*II);
     482             :     }
     483             : 
     484             :     // Delete the dead blocks and any of their dead successors.
     485      198465 :     MadeChange |= !WorkList.empty();
     486      200149 :     while (!WorkList.empty()) {
     487             :       BasicBlock *BB = WorkList.pop_back_val();
     488        1684 :       SmallVector<BasicBlock*, 2> Successors(succ_begin(BB), succ_end(BB));
     489             : 
     490        1684 :       DeleteDeadBlock(BB);
     491             : 
     492        1382 :       for (SmallVectorImpl<BasicBlock*>::iterator
     493        3066 :              II = Successors.begin(), IE = Successors.end(); II != IE; ++II)
     494        1382 :         if (pred_begin(*II) == pred_end(*II))
     495         775 :           WorkList.insert(*II);
     496             :     }
     497             : 
     498             :     // Merge pairs of basic blocks with unconditional branches, connected by
     499             :     // a single edge.
     500      198465 :     if (EverMadeChange || MadeChange)
     501       12219 :       MadeChange |= eliminateFallThrough(F);
     502             : 
     503      198465 :     EverMadeChange |= MadeChange;
     504             :   }
     505             : 
     506      198528 :   if (!DisableGCOpts) {
     507             :     SmallVector<Instruction *, 2> Statepoints;
     508      614070 :     for (BasicBlock &BB : F)
     509     3533670 :       for (Instruction &I : BB)
     510     3118128 :         if (isStatepoint(I))
     511          76 :           Statepoints.push_back(&I);
     512      198604 :     for (auto &I : Statepoints)
     513          76 :       EverMadeChange |= simplifyOffsetableRelocate(*I);
     514             :   }
     515             : 
     516             :   // Do this last to clean up use-before-def scenarios introduced by other
     517             :   // preparatory transforms.
     518      198528 :   EverMadeChange |= placeDbgValues(F);
     519             : 
     520      198528 :   return EverMadeChange;
     521             : }
     522             : 
     523             : /// Merge basic blocks which are connected by a single edge, where one of the
     524             : /// basic blocks has a single successor pointing to the other basic block,
     525             : /// which has a single predecessor.
     526           0 : bool CodeGenPrepare::eliminateFallThrough(Function &F) {
     527             :   bool Changed = false;
     528             :   // Scan all of the blocks in the function, except for the entry block.
     529             :   // Use a temporary array to avoid iterator being invalidated when
     530             :   // deleting blocks.
     531           0 :   SmallVector<WeakTrackingVH, 16> Blocks;
     532           0 :   for (auto &Block : llvm::make_range(std::next(F.begin()), F.end()))
     533           0 :     Blocks.push_back(&Block);
     534             : 
     535           0 :   for (auto &Block : Blocks) {
     536             :     auto *BB = cast_or_null<BasicBlock>(Block);
     537           0 :     if (!BB)
     538           0 :       continue;
     539             :     // If the destination block has a single pred, then this is a trivial
     540             :     // edge, just collapse it.
     541             :     BasicBlock *SinglePred = BB->getSinglePredecessor();
     542             : 
     543             :     // Don't merge if BB's address is taken.
     544           0 :     if (!SinglePred || SinglePred == BB || BB->hasAddressTaken()) continue;
     545             : 
     546             :     BranchInst *Term = dyn_cast<BranchInst>(SinglePred->getTerminator());
     547           0 :     if (Term && !Term->isConditional()) {
     548             :       Changed = true;
     549             :       LLVM_DEBUG(dbgs() << "To merge:\n" << *BB << "\n\n\n");
     550             : 
     551             :       // Merge BB into SinglePred and delete it.
     552           0 :       MergeBlockIntoPredecessor(BB);
     553             :     }
     554             :   }
     555           0 :   return Changed;
     556             : }
     557             : 
     558             : /// Find a destination block from BB if BB is mergeable empty block.
     559           0 : BasicBlock *CodeGenPrepare::findDestBlockOfMergeableEmptyBlock(BasicBlock *BB) {
     560             :   // If this block doesn't end with an uncond branch, ignore it.
     561             :   BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator());
     562           0 :   if (!BI || !BI->isUnconditional())
     563           0 :     return nullptr;
     564             : 
     565             :   // If the instruction before the branch (skipping debug info) isn't a phi
     566             :   // node, then other stuff is happening here.
     567           0 :   BasicBlock::iterator BBI = BI->getIterator();
     568           0 :   if (BBI != BB->begin()) {
     569             :     --BBI;
     570           0 :     while (isa<DbgInfoIntrinsic>(BBI)) {
     571           0 :       if (BBI == BB->begin())
     572             :         break;
     573             :       --BBI;
     574             :     }
     575           0 :     if (!isa<DbgInfoIntrinsic>(BBI) && !isa<PHINode>(BBI))
     576           0 :       return nullptr;
     577             :   }
     578             : 
     579             :   // Do not break infinite loops.
     580             :   BasicBlock *DestBB = BI->getSuccessor(0);
     581           0 :   if (DestBB == BB)
     582           0 :     return nullptr;
     583             : 
     584           0 :   if (!canMergeBlocks(BB, DestBB))
     585             :     DestBB = nullptr;
     586             : 
     587             :   return DestBB;
     588             : }
     589             : 
     590             : /// Eliminate blocks that contain only PHI nodes, debug info directives, and an
     591             : /// unconditional branch. Passes before isel (e.g. LSR/loopsimplify) often split
     592             : /// edges in ways that are non-optimal for isel. Start by eliminating these
     593             : /// blocks so we can split them the way we want them.
     594      198528 : bool CodeGenPrepare::eliminateMostlyEmptyBlocks(Function &F) {
     595             :   SmallPtrSet<BasicBlock *, 16> Preheaders;
     596      198528 :   SmallVector<Loop *, 16> LoopList(LI->begin(), LI->end());
     597      206410 :   while (!LoopList.empty()) {
     598             :     Loop *L = LoopList.pop_back_val();
     599        7882 :     LoopList.insert(LoopList.end(), L->begin(), L->end());
     600        7882 :     if (BasicBlock *Preheader = L->getLoopPreheader())
     601        7745 :       Preheaders.insert(Preheader);
     602             :   }
     603             : 
     604             :   bool MadeChange = false;
     605             :   // Copy blocks into a temporary array to avoid iterator invalidation issues
     606             :   // as we remove them.
     607             :   // Note that this intentionally skips the entry block.
     608      198528 :   SmallVector<WeakTrackingVH, 16> Blocks;
     609      423062 :   for (auto &Block : llvm::make_range(std::next(F.begin()), F.end()))
     610      673602 :     Blocks.push_back(&Block);
     611             : 
     612      423062 :   for (auto &Block : Blocks) {
     613             :     BasicBlock *BB = cast_or_null<BasicBlock>(Block);
     614             :     if (!BB)
     615             :       continue;
     616      224534 :     BasicBlock *DestBB = findDestBlockOfMergeableEmptyBlock(BB);
     617      231116 :     if (!DestBB ||
     618        6582 :         !isMergingEmptyBlockProfitable(BB, DestBB, Preheaders.count(BB)))
     619      219978 :       continue;
     620             : 
     621        4556 :     eliminateMostlyEmptyBlock(BB);
     622             :     MadeChange = true;
     623             :   }
     624      198528 :   return MadeChange;
     625             : }
     626             : 
     627        6582 : bool CodeGenPrepare::isMergingEmptyBlockProfitable(BasicBlock *BB,
     628             :                                                    BasicBlock *DestBB,
     629             :                                                    bool isPreheader) {
     630             :   // Do not delete loop preheaders if doing so would create a critical edge.
     631             :   // Loop preheaders can be good locations to spill registers. If the
     632             :   // preheader is deleted and we create a critical edge, registers may be
     633             :   // spilled in the loop body instead.
     634        8564 :   if (!DisablePreheaderProtect && isPreheader &&
     635        3845 :       !(BB->getSinglePredecessor() &&
     636        1863 :         BB->getSinglePredecessor()->getSingleSuccessor()))
     637        1976 :     return false;
     638             : 
     639             :   // Try to skip merging if the unique predecessor of BB is terminated by a
     640             :   // switch or indirect branch instruction, and BB is used as an incoming block
     641             :   // of PHIs in DestBB. In such case, merging BB and DestBB would cause ISel to
     642             :   // add COPY instructions in the predecessor of BB instead of BB (if it is not
     643             :   // merged). Note that the critical edge created by merging such blocks wont be
     644             :   // split in MachineSink because the jump table is not analyzable. By keeping
     645             :   // such empty block (BB), ISel will place COPY instructions in BB, not in the
     646             :   // predecessor of BB.
     647        4606 :   BasicBlock *Pred = BB->getUniquePredecessor();
     648        4606 :   if (!Pred ||
     649        3451 :       !(isa<SwitchInst>(Pred->getTerminator()) ||
     650             :         isa<IndirectBrInst>(Pred->getTerminator())))
     651             :     return true;
     652             : 
     653         423 :   if (BB->getTerminator() != BB->getFirstNonPHIOrDbg())
     654             :     return true;
     655             : 
     656             :   // We use a simple cost heuristic which determine skipping merging is
     657             :   // profitable if the cost of skipping merging is less than the cost of
     658             :   // merging : Cost(skipping merging) < Cost(merging BB), where the
     659             :   // Cost(skipping merging) is Freq(BB) * (Cost(Copy) + Cost(Branch)), and
     660             :   // the Cost(merging BB) is Freq(Pred) * Cost(Copy).
     661             :   // Assuming Cost(Copy) == Cost(Branch), we could simplify it to :
     662             :   //   Freq(Pred) / Freq(BB) > 2.
     663             :   // Note that if there are multiple empty blocks sharing the same incoming
     664             :   // value for the PHIs in the DestBB, we consider them together. In such
     665             :   // case, Cost(merging BB) will be the sum of their frequencies.
     666             : 
     667         423 :   if (!isa<PHINode>(DestBB->begin()))
     668             :     return true;
     669             : 
     670             :   SmallPtrSet<BasicBlock *, 16> SameIncomingValueBBs;
     671             : 
     672             :   // Find all other incoming blocks from which incoming values of all PHIs in
     673             :   // DestBB are the same as the ones from BB.
     674         324 :   for (pred_iterator PI = pred_begin(DestBB), E = pred_end(DestBB); PI != E;
     675             :        ++PI) {
     676         255 :     BasicBlock *DestBBPred = *PI;
     677         255 :     if (DestBBPred == BB)
     678          69 :       continue;
     679             : 
     680         372 :     if (llvm::all_of(DestBB->phis(), [&](const PHINode &DestPN) {
     681             :           return DestPN.getIncomingValueForBlock(BB) ==
     682             :                  DestPN.getIncomingValueForBlock(DestBBPred);
     683             :         }))
     684          36 :       SameIncomingValueBBs.insert(DestBBPred);
     685             :   }
     686             : 
     687             :   // See if all BB's incoming values are same as the value from Pred. In this
     688             :   // case, no reason to skip merging because COPYs are expected to be place in
     689             :   // Pred already.
     690          69 :   if (SameIncomingValueBBs.count(Pred))
     691             :     return true;
     692             : 
     693          63 :   BlockFrequency PredFreq = BFI->getBlockFreq(Pred);
     694          63 :   BlockFrequency BBFreq = BFI->getBlockFreq(BB);
     695             : 
     696          78 :   for (auto SameValueBB : SameIncomingValueBBs)
     697          22 :     if (SameValueBB->getUniquePredecessor() == Pred &&
     698           7 :         DestBB == findDestBlockOfMergeableEmptyBlock(SameValueBB))
     699           4 :       BBFreq += BFI->getBlockFreq(SameValueBB);
     700             : 
     701          63 :   return PredFreq.getFrequency() <=
     702         126 :          BBFreq.getFrequency() * FreqRatioToSkipMerge;
     703             : }
     704             : 
     705             : /// Return true if we can merge BB into DestBB if there is a single
     706             : /// unconditional branch between them, and BB contains no other non-phi
     707             : /// instructions.
     708           0 : bool CodeGenPrepare::canMergeBlocks(const BasicBlock *BB,
     709             :                                     const BasicBlock *DestBB) const {
     710             :   // We only want to eliminate blocks whose phi nodes are used by phi nodes in
     711             :   // the successor.  If there are more complex condition (e.g. preheaders),
     712             :   // don't mess around with them.
     713           0 :   for (const PHINode &PN : BB->phis()) {
     714           0 :     for (const User *U : PN.users()) {
     715             :       const Instruction *UI = cast<Instruction>(U);
     716           0 :       if (UI->getParent() != DestBB || !isa<PHINode>(UI))
     717           0 :         return false;
     718             :       // If User is inside DestBB block and it is a PHINode then check
     719             :       // incoming value. If incoming value is not from BB then this is
     720             :       // a complex condition (e.g. preheaders) we want to avoid here.
     721             :       if (UI->getParent() == DestBB) {
     722             :         if (const PHINode *UPN = dyn_cast<PHINode>(UI))
     723           0 :           for (unsigned I = 0, E = UPN->getNumIncomingValues(); I != E; ++I) {
     724             :             Instruction *Insn = dyn_cast<Instruction>(UPN->getIncomingValue(I));
     725           0 :             if (Insn && Insn->getParent() == BB &&
     726             :                 Insn->getParent() != UPN->getIncomingBlock(I))
     727           0 :               return false;
     728             :           }
     729             :       }
     730             :     }
     731             :   }
     732             : 
     733             :   // If BB and DestBB contain any common predecessors, then the phi nodes in BB
     734             :   // and DestBB may have conflicting incoming values for the block.  If so, we
     735             :   // can't merge the block.
     736             :   const PHINode *DestBBPN = dyn_cast<PHINode>(DestBB->begin());
     737           0 :   if (!DestBBPN) return true;  // no conflict.
     738             : 
     739             :   // Collect the preds of BB.
     740             :   SmallPtrSet<const BasicBlock*, 16> BBPreds;
     741             :   if (const PHINode *BBPN = dyn_cast<PHINode>(BB->begin())) {
     742             :     // It is faster to get preds from a PHI than with pred_iterator.
     743           0 :     for (unsigned i = 0, e = BBPN->getNumIncomingValues(); i != e; ++i)
     744           0 :       BBPreds.insert(BBPN->getIncomingBlock(i));
     745             :   } else {
     746           0 :     BBPreds.insert(pred_begin(BB), pred_end(BB));
     747             :   }
     748             : 
     749             :   // Walk the preds of DestBB.
     750           0 :   for (unsigned i = 0, e = DestBBPN->getNumIncomingValues(); i != e; ++i) {
     751             :     BasicBlock *Pred = DestBBPN->getIncomingBlock(i);
     752           0 :     if (BBPreds.count(Pred)) {   // Common predecessor?
     753           0 :       for (const PHINode &PN : DestBB->phis()) {
     754           0 :         const Value *V1 = PN.getIncomingValueForBlock(Pred);
     755           0 :         const Value *V2 = PN.getIncomingValueForBlock(BB);
     756             : 
     757             :         // If V2 is a phi node in BB, look up what the mapped value will be.
     758             :         if (const PHINode *V2PN = dyn_cast<PHINode>(V2))
     759           0 :           if (V2PN->getParent() == BB)
     760           0 :             V2 = V2PN->getIncomingValueForBlock(Pred);
     761             : 
     762             :         // If there is a conflict, bail out.
     763           0 :         if (V1 != V2) return false;
     764             :       }
     765             :     }
     766             :   }
     767             : 
     768             :   return true;
     769             : }
     770             : 
     771             : /// Eliminate a basic block that has only phi's and an unconditional branch in
     772             : /// it.
     773           0 : void CodeGenPrepare::eliminateMostlyEmptyBlock(BasicBlock *BB) {
     774             :   BranchInst *BI = cast<BranchInst>(BB->getTerminator());
     775             :   BasicBlock *DestBB = BI->getSuccessor(0);
     776             : 
     777             :   LLVM_DEBUG(dbgs() << "MERGING MOSTLY EMPTY BLOCKS - BEFORE:\n"
     778             :                     << *BB << *DestBB);
     779             : 
     780             :   // If the destination block has a single pred, then this is a trivial edge,
     781             :   // just collapse it.
     782           0 :   if (BasicBlock *SinglePred = DestBB->getSinglePredecessor()) {
     783           0 :     if (SinglePred != DestBB) {
     784             :       assert(SinglePred == BB &&
     785             :              "Single predecessor not the same as predecessor");
     786             :       // Merge DestBB into SinglePred/BB and delete it.
     787           0 :       MergeBlockIntoPredecessor(DestBB);
     788             :       // Note: BB(=SinglePred) will not be deleted on this path.
     789             :       // DestBB(=its single successor) is the one that was deleted.
     790             :       LLVM_DEBUG(dbgs() << "AFTER:\n" << *SinglePred << "\n\n\n");
     791           0 :       return;
     792             :     }
     793             :   }
     794             : 
     795             :   // Otherwise, we have multiple predecessors of BB.  Update the PHIs in DestBB
     796             :   // to handle the new incoming edges it is about to have.
     797           0 :   for (PHINode &PN : DestBB->phis()) {
     798             :     // Remove the incoming value for BB, and remember it.
     799             :     Value *InVal = PN.removeIncomingValue(BB, false);
     800             : 
     801             :     // Two options: either the InVal is a phi node defined in BB or it is some
     802             :     // value that dominates BB.
     803             :     PHINode *InValPhi = dyn_cast<PHINode>(InVal);
     804           0 :     if (InValPhi && InValPhi->getParent() == BB) {
     805             :       // Add all of the input values of the input PHI as inputs of this phi.
     806           0 :       for (unsigned i = 0, e = InValPhi->getNumIncomingValues(); i != e; ++i)
     807           0 :         PN.addIncoming(InValPhi->getIncomingValue(i),
     808             :                        InValPhi->getIncomingBlock(i));
     809             :     } else {
     810             :       // Otherwise, add one instance of the dominating value for each edge that
     811             :       // we will be adding.
     812             :       if (PHINode *BBPN = dyn_cast<PHINode>(BB->begin())) {
     813           0 :         for (unsigned i = 0, e = BBPN->getNumIncomingValues(); i != e; ++i)
     814           0 :           PN.addIncoming(InVal, BBPN->getIncomingBlock(i));
     815             :       } else {
     816           0 :         for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
     817           0 :           PN.addIncoming(InVal, *PI);
     818             :       }
     819             :     }
     820             :   }
     821             : 
     822             :   // The PHIs are now updated, change everything that refers to BB to use
     823             :   // DestBB and remove BB.
     824           0 :   BB->replaceAllUsesWith(DestBB);
     825           0 :   BB->eraseFromParent();
     826             :   ++NumBlocksElim;
     827             : 
     828             :   LLVM_DEBUG(dbgs() << "AFTER:\n" << *DestBB << "\n\n\n");
     829             : }
     830             : 
     831             : // Computes a map of base pointer relocation instructions to corresponding
     832             : // derived pointer relocation instructions given a vector of all relocate calls
     833          25 : static void computeBaseDerivedRelocateMap(
     834             :     const SmallVectorImpl<GCRelocateInst *> &AllRelocateCalls,
     835             :     DenseMap<GCRelocateInst *, SmallVector<GCRelocateInst *, 2>>
     836             :         &RelocateInstMap) {
     837             :   // Collect information in two maps: one primarily for locating the base object
     838             :   // while filling the second map; the second map is the final structure holding
     839             :   // a mapping between Base and corresponding Derived relocate calls
     840             :   DenseMap<std::pair<unsigned, unsigned>, GCRelocateInst *> RelocateIdxMap;
     841          87 :   for (auto *ThisRelocate : AllRelocateCalls) {
     842             :     auto K = std::make_pair(ThisRelocate->getBasePtrIndex(),
     843             :                             ThisRelocate->getDerivedPtrIndex());
     844          62 :     RelocateIdxMap.insert(std::make_pair(K, ThisRelocate));
     845             :   }
     846         112 :   for (auto &Item : RelocateIdxMap) {
     847          62 :     std::pair<unsigned, unsigned> Key = Item.first;
     848          62 :     if (Key.first == Key.second)
     849             :       // Base relocation: nothing to insert
     850          36 :       continue;
     851             : 
     852          28 :     GCRelocateInst *I = Item.second;
     853          28 :     auto BaseKey = std::make_pair(Key.first, Key.first);
     854             : 
     855             :     // We're iterating over RelocateIdxMap so we cannot modify it.
     856          28 :     auto MaybeBase = RelocateIdxMap.find(BaseKey);
     857          28 :     if (MaybeBase == RelocateIdxMap.end())
     858             :       // TODO: We might want to insert a new base object relocate and gep off
     859             :       // that, if there are enough derived object relocates.
     860             :       continue;
     861             : 
     862          26 :     RelocateInstMap[MaybeBase->second].push_back(I);
     863             :   }
     864          25 : }
     865             : 
     866             : // Accepts a GEP and extracts the operands into a vector provided they're all
     867             : // small integer constants
     868          11 : static bool getGEPSmallConstantIntOffsetV(GetElementPtrInst *GEP,
     869             :                                           SmallVectorImpl<Value *> &OffsetV) {
     870          21 :   for (unsigned i = 1; i < GEP->getNumOperands(); i++) {
     871             :     // Only accept small constant integer operands
     872             :     auto Op = dyn_cast<ConstantInt>(GEP->getOperand(i));
     873          11 :     if (!Op || Op->getZExtValue() > 20)
     874             :       return false;
     875             :   }
     876             : 
     877          17 :   for (unsigned i = 1; i < GEP->getNumOperands(); i++)
     878           9 :     OffsetV.push_back(GEP->getOperand(i));
     879             :   return true;
     880             : }
     881             : 
     882             : // Takes a RelocatedBase (base pointer relocation instruction) and Targets to
     883             : // replace, computes a replacement, and affects it.
     884             : static bool
     885          18 : simplifyRelocatesOffABase(GCRelocateInst *RelocatedBase,
     886             :                           const SmallVectorImpl<GCRelocateInst *> &Targets) {
     887             :   bool MadeChange = false;
     888             :   // We must ensure the relocation of derived pointer is defined after
     889             :   // relocation of base pointer. If we find a relocation corresponding to base
     890             :   // defined earlier than relocation of base then we move relocation of base
     891             :   // right before found relocation. We consider only relocation in the same
     892             :   // basic block as relocation of base. Relocations from other basic block will
     893             :   // be skipped by optimization and we do not care about them.
     894          36 :   for (auto R = RelocatedBase->getParent()->getFirstInsertionPt();
     895         128 :        &*R != RelocatedBase; ++R)
     896          12 :     if (auto RI = dyn_cast<GCRelocateInst>(R))
     897          12 :       if (RI->getStatepoint() == RelocatedBase->getStatepoint())
     898           6 :         if (RI->getBasePtrIndex() == RelocatedBase->getBasePtrIndex()) {
     899           6 :           RelocatedBase->moveBefore(RI);
     900           6 :           break;
     901             :         }
     902             : 
     903          44 :   for (GCRelocateInst *ToReplace : Targets) {
     904             :     assert(ToReplace->getBasePtrIndex() == RelocatedBase->getBasePtrIndex() &&
     905             :            "Not relocating a derived object of the original base object");
     906          26 :     if (ToReplace->getBasePtrIndex() == ToReplace->getDerivedPtrIndex()) {
     907             :       // A duplicate relocate call. TODO: coalesce duplicates.
     908          18 :       continue;
     909             :     }
     910             : 
     911          26 :     if (RelocatedBase->getParent() != ToReplace->getParent()) {
     912             :       // Base and derived relocates are in different basic blocks.
     913             :       // In this case transform is only valid when base dominates derived
     914             :       // relocate. However it would be too expensive to check dominance
     915             :       // for each such relocate, so we skip the whole transformation.
     916             :       continue;
     917             :     }
     918             : 
     919          25 :     Value *Base = ToReplace->getBasePtr();
     920          25 :     auto Derived = dyn_cast<GetElementPtrInst>(ToReplace->getDerivedPtr());
     921          11 :     if (!Derived || Derived->getPointerOperand() != Base)
     922             :       continue;
     923             : 
     924             :     SmallVector<Value *, 2> OffsetV;
     925          11 :     if (!getGEPSmallConstantIntOffsetV(Derived, OffsetV))
     926             :       continue;
     927             : 
     928             :     // Create a Builder and replace the target callsite with a gep
     929             :     assert(RelocatedBase->getNextNode() &&
     930             :            "Should always have one since it's not a terminator");
     931             : 
     932             :     // Insert after RelocatedBase
     933           8 :     IRBuilder<> Builder(RelocatedBase->getNextNode());
     934           8 :     Builder.SetCurrentDebugLocation(ToReplace->getDebugLoc());
     935             : 
     936             :     // If gc_relocate does not match the actual type, cast it to the right type.
     937             :     // In theory, there must be a bitcast after gc_relocate if the type does not
     938             :     // match, and we should reuse it to get the derived pointer. But it could be
     939             :     // cases like this:
     940             :     // bb1:
     941             :     //  ...
     942             :     //  %g1 = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(...)
     943             :     //  br label %merge
     944             :     //
     945             :     // bb2:
     946             :     //  ...
     947             :     //  %g2 = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(...)
     948             :     //  br label %merge
     949             :     //
     950             :     // merge:
     951             :     //  %p1 = phi i8 addrspace(1)* [ %g1, %bb1 ], [ %g2, %bb2 ]
     952             :     //  %cast = bitcast i8 addrspace(1)* %p1 in to i32 addrspace(1)*
     953             :     //
     954             :     // In this case, we can not find the bitcast any more. So we insert a new bitcast
     955             :     // no matter there is already one or not. In this way, we can handle all cases, and
     956             :     // the extra bitcast should be optimized away in later passes.
     957             :     Value *ActualRelocatedBase = RelocatedBase;
     958           8 :     if (RelocatedBase->getType() != Base->getType()) {
     959             :       ActualRelocatedBase =
     960           0 :           Builder.CreateBitCast(RelocatedBase, Base->getType());
     961             :     }
     962           8 :     Value *Replacement = Builder.CreateGEP(
     963             :         Derived->getSourceElementType(), ActualRelocatedBase, makeArrayRef(OffsetV));
     964           8 :     Replacement->takeName(ToReplace);
     965             :     // If the newly generated derived pointer's type does not match the original derived
     966             :     // pointer's type, cast the new derived pointer to match it. Same reasoning as above.
     967             :     Value *ActualReplacement = Replacement;
     968           8 :     if (Replacement->getType() != ToReplace->getType()) {
     969             :       ActualReplacement =
     970           0 :           Builder.CreateBitCast(Replacement, ToReplace->getType());
     971             :     }
     972           8 :     ToReplace->replaceAllUsesWith(ActualReplacement);
     973           8 :     ToReplace->eraseFromParent();
     974             : 
     975             :     MadeChange = true;
     976             :   }
     977          18 :   return MadeChange;
     978             : }
     979             : 
     980             : // Turns this:
     981             : //
     982             : // %base = ...
     983             : // %ptr = gep %base + 15
     984             : // %tok = statepoint (%fun, i32 0, i32 0, i32 0, %base, %ptr)
     985             : // %base' = relocate(%tok, i32 4, i32 4)
     986             : // %ptr' = relocate(%tok, i32 4, i32 5)
     987             : // %val = load %ptr'
     988             : //
     989             : // into this:
     990             : //
     991             : // %base = ...
     992             : // %ptr = gep %base + 15
     993             : // %tok = statepoint (%fun, i32 0, i32 0, i32 0, %base, %ptr)
     994             : // %base' = gc.relocate(%tok, i32 4, i32 4)
     995             : // %ptr' = gep %base' + 15
     996             : // %val = load %ptr'
     997           0 : bool CodeGenPrepare::simplifyOffsetableRelocate(Instruction &I) {
     998             :   bool MadeChange = false;
     999             :   SmallVector<GCRelocateInst *, 2> AllRelocateCalls;
    1000             : 
    1001           0 :   for (auto *U : I.users())
    1002           0 :     if (GCRelocateInst *Relocate = dyn_cast<GCRelocateInst>(U))
    1003             :       // Collect all the relocate calls associated with a statepoint
    1004           0 :       AllRelocateCalls.push_back(Relocate);
    1005             : 
    1006             :   // We need atleast one base pointer relocation + one derived pointer
    1007             :   // relocation to mangle
    1008           0 :   if (AllRelocateCalls.size() < 2)
    1009           0 :     return false;
    1010             : 
    1011             :   // RelocateInstMap is a mapping from the base relocate instruction to the
    1012             :   // corresponding derived relocate instructions
    1013             :   DenseMap<GCRelocateInst *, SmallVector<GCRelocateInst *, 2>> RelocateInstMap;
    1014           0 :   computeBaseDerivedRelocateMap(AllRelocateCalls, RelocateInstMap);
    1015           0 :   if (RelocateInstMap.empty())
    1016           0 :     return false;
    1017             : 
    1018           0 :   for (auto &Item : RelocateInstMap)
    1019             :     // Item.first is the RelocatedBase to offset against
    1020             :     // Item.second is the vector of Targets to replace
    1021           0 :     MadeChange = simplifyRelocatesOffABase(Item.first, Item.second);
    1022           0 :   return MadeChange;
    1023             : }
    1024             : 
    1025             : /// SinkCast - Sink the specified cast instruction into its user blocks
    1026      395765 : static bool SinkCast(CastInst *CI) {
    1027      395765 :   BasicBlock *DefBB = CI->getParent();
    1028             : 
    1029             :   /// InsertedCasts - Only insert a cast in each block once.
    1030             :   DenseMap<BasicBlock*, CastInst*> InsertedCasts;
    1031             : 
    1032             :   bool MadeChange = false;
    1033             :   for (Value::user_iterator UI = CI->user_begin(), E = CI->user_end();
    1034      878043 :        UI != E; ) {
    1035             :     Use &TheUse = UI.getUse();
    1036             :     Instruction *User = cast<Instruction>(*UI);
    1037             : 
    1038             :     // Figure out which BB this cast is used in.  For PHI's this is the
    1039             :     // appropriate predecessor block.
    1040      482278 :     BasicBlock *UserBB = User->getParent();
    1041             :     if (PHINode *PN = dyn_cast<PHINode>(User)) {
    1042        9773 :       UserBB = PN->getIncomingBlock(TheUse);
    1043             :     }
    1044             : 
    1045             :     // Preincrement use iterator so we don't invalidate it.
    1046             :     ++UI;
    1047             : 
    1048             :     // The first insertion point of a block containing an EH pad is after the
    1049             :     // pad.  If the pad is the user, we cannot sink the cast past the pad.
    1050             :     if (User->isEHPad())
    1051      405788 :       continue;
    1052             : 
    1053             :     // If the block selected to receive the cast is an EH pad that does not
    1054             :     // allow non-PHI instructions before the terminator, we can't sink the
    1055             :     // cast.
    1056      482277 :     if (UserBB->getTerminator()->isEHPad())
    1057             :       continue;
    1058             : 
    1059             :     // If this user is in the same block as the cast, don't change the cast.
    1060      482277 :     if (UserBB == DefBB) continue;
    1061             : 
    1062             :     // If we have already inserted a cast into this block, use it.
    1063             :     CastInst *&InsertedCast = InsertedCasts[UserBB];
    1064             : 
    1065       76490 :     if (!InsertedCast) {
    1066       74360 :       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
    1067             :       assert(InsertPt != UserBB->end());
    1068       74360 :       InsertedCast = CastInst::Create(CI->getOpcode(), CI->getOperand(0),
    1069             :                                       CI->getType(), "", &*InsertPt);
    1070       74360 :       InsertedCast->setDebugLoc(CI->getDebugLoc());
    1071             :     }
    1072             : 
    1073             :     // Replace a use of the cast with a use of the new cast.
    1074       76490 :     TheUse = InsertedCast;
    1075             :     MadeChange = true;
    1076             :     ++NumCastUses;
    1077             :   }
    1078             : 
    1079             :   // If we removed all uses, nuke the cast.
    1080      395765 :   if (CI->use_empty()) {
    1081       10018 :     salvageDebugInfo(*CI);
    1082       10018 :     CI->eraseFromParent();
    1083             :     MadeChange = true;
    1084             :   }
    1085             : 
    1086      395765 :   return MadeChange;
    1087             : }
    1088             : 
    1089             : /// If the specified cast instruction is a noop copy (e.g. it's casting from
    1090             : /// one pointer type to another, i32->i8 on PPC), sink it into user blocks to
    1091             : /// reduce the number of virtual registers that must be created and coalesced.
    1092             : ///
    1093             : /// Return true if any changes are made.
    1094      499999 : static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI,
    1095             :                                        const DataLayout &DL) {
    1096             :   // Sink only "cheap" (or nop) address-space casts.  This is a weaker condition
    1097             :   // than sinking only nop casts, but is helpful on some platforms.
    1098             :   if (auto *ASC = dyn_cast<AddrSpaceCastInst>(CI)) {
    1099         294 :     if (!TLI.isCheapAddrSpaceCast(ASC->getSrcAddressSpace(),
    1100         294 :                                   ASC->getDestAddressSpace()))
    1101             :       return false;
    1102             :   }
    1103             : 
    1104             :   // If this is a noop copy,
    1105      499846 :   EVT SrcVT = TLI.getValueType(DL, CI->getOperand(0)->getType());
    1106      499846 :   EVT DstVT = TLI.getValueType(DL, CI->getType());
    1107             : 
    1108             :   // This is an fp<->int conversion?
    1109      499846 :   if (SrcVT.isInteger() != DstVT.isInteger())
    1110             :     return false;
    1111             : 
    1112             :   // If this is an extension, it will be a zero or sign extension, which
    1113             :   // isn't a noop.
    1114      479061 :   if (SrcVT.bitsLT(DstVT)) return false;
    1115             : 
    1116             :   // If these values will be promoted, find out what they will be promoted
    1117             :   // to.  This helps us consider truncates on PPC as noop copies when they
    1118             :   // are.
    1119      861874 :   if (TLI.getTypeAction(CI->getContext(), SrcVT) ==
    1120             :       TargetLowering::TypePromoteInteger)
    1121        2640 :     SrcVT = TLI.getTypeToTransformTo(CI->getContext(), SrcVT);
    1122      861874 :   if (TLI.getTypeAction(CI->getContext(), DstVT) ==
    1123             :       TargetLowering::TypePromoteInteger)
    1124       13186 :     DstVT = TLI.getTypeToTransformTo(CI->getContext(), DstVT);
    1125             : 
    1126             :   // If, after promotion, these are the same types, this is a noop copy.
    1127      430999 :   if (SrcVT != DstVT)
    1128             :     return false;
    1129             : 
    1130      392121 :   return SinkCast(CI);
    1131             : }
    1132             : 
    1133             : /// Try to combine CI into a call to the llvm.uadd.with.overflow intrinsic if
    1134             : /// possible.
    1135             : ///
    1136             : /// Return true if any changes were made.
    1137      143764 : static bool CombineUAddWithOverflow(CmpInst *CI) {
    1138             :   Value *A, *B;
    1139             :   Instruction *AddI;
    1140      143764 :   if (!match(CI,
    1141      143764 :              m_UAddWithOverflow(m_Value(A), m_Value(B), m_Instruction(AddI))))
    1142             :     return false;
    1143             : 
    1144         428 :   Type *Ty = AddI->getType();
    1145         428 :   if (!isa<IntegerType>(Ty))
    1146             :     return false;
    1147             : 
    1148             :   // We don't want to move around uses of condition values this late, so we we
    1149             :   // check if it is legal to create the call to the intrinsic in the basic
    1150             :   // block containing the icmp:
    1151             : 
    1152          99 :   if (AddI->getParent() != CI->getParent() && !AddI->hasOneUse())
    1153             :     return false;
    1154             : 
    1155             : #ifndef NDEBUG
    1156             :   // Someday m_UAddWithOverflow may get smarter, but this is a safe assumption
    1157             :   // for now:
    1158             :   if (AddI->hasOneUse())
    1159             :     assert(*AddI->user_begin() == CI && "expected!");
    1160             : #endif
    1161             : 
    1162          81 :   Module *M = CI->getModule();
    1163          81 :   Value *F = Intrinsic::getDeclaration(M, Intrinsic::uadd_with_overflow, Ty);
    1164             : 
    1165          81 :   auto *InsertPt = AddI->hasOneUse() ? CI : AddI;
    1166             : 
    1167             :   DebugLoc Loc = CI->getDebugLoc();
    1168             :   auto *UAddWithOverflow =
    1169          81 :       CallInst::Create(F, {A, B}, "uadd.overflow", InsertPt);
    1170          81 :   UAddWithOverflow->setDebugLoc(Loc);
    1171         162 :   auto *UAdd = ExtractValueInst::Create(UAddWithOverflow, 0, "uadd", InsertPt);
    1172          81 :   UAdd->setDebugLoc(Loc);
    1173             :   auto *Overflow =
    1174         162 :       ExtractValueInst::Create(UAddWithOverflow, 1, "overflow", InsertPt);
    1175          81 :   Overflow->setDebugLoc(Loc);
    1176             : 
    1177          81 :   CI->replaceAllUsesWith(Overflow);
    1178          81 :   AddI->replaceAllUsesWith(UAdd);
    1179          81 :   CI->eraseFromParent();
    1180          81 :   AddI->eraseFromParent();
    1181             :   return true;
    1182             : }
    1183             : 
    1184             : /// Sink the given CmpInst into user blocks to reduce the number of virtual
    1185             : /// registers that must be created and coalesced. This is a clear win except on
    1186             : /// targets with multiple condition code registers (PowerPC), where it might
    1187             : /// lose; some adjustment may be wanted there.
    1188             : ///
    1189             : /// Return true if any changes are made.
    1190      145212 : static bool SinkCmpExpression(CmpInst *CI, const TargetLowering *TLI) {
    1191      145212 :   BasicBlock *DefBB = CI->getParent();
    1192             : 
    1193             :   // Avoid sinking soft-FP comparisons, since this can move them into a loop.
    1194      145212 :   if (TLI && TLI->useSoftFloat() && isa<FCmpInst>(CI))
    1195             :     return false;
    1196             : 
    1197             :   // Only insert a cmp in each block once.
    1198             :   DenseMap<BasicBlock*, CmpInst*> InsertedCmps;
    1199             : 
    1200             :   bool MadeChange = false;
    1201             :   for (Value::user_iterator UI = CI->user_begin(), E = CI->user_end();
    1202      292652 :        UI != E; ) {
    1203             :     Use &TheUse = UI.getUse();
    1204             :     Instruction *User = cast<Instruction>(*UI);
    1205             : 
    1206             :     // Preincrement use iterator so we don't invalidate it.
    1207             :     ++UI;
    1208             : 
    1209             :     // Don't bother for PHI nodes.
    1210      147485 :     if (isa<PHINode>(User))
    1211      145726 :       continue;
    1212             : 
    1213             :     // Figure out which BB this cmp is used in.
    1214      146696 :     BasicBlock *UserBB = User->getParent();
    1215             : 
    1216             :     // If this user is in the same block as the cmp, don't change the cmp.
    1217      146696 :     if (UserBB == DefBB) continue;
    1218             : 
    1219             :     // If we have already inserted a cmp into this block, use it.
    1220             :     CmpInst *&InsertedCmp = InsertedCmps[UserBB];
    1221             : 
    1222        1759 :     if (!InsertedCmp) {
    1223        1639 :       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
    1224             :       assert(InsertPt != UserBB->end());
    1225        1639 :       InsertedCmp =
    1226        1639 :           CmpInst::Create(CI->getOpcode(), CI->getPredicate(),
    1227             :                           CI->getOperand(0), CI->getOperand(1), "", &*InsertPt);
    1228             :       // Propagate the debug info.
    1229        1639 :       InsertedCmp->setDebugLoc(CI->getDebugLoc());
    1230             :     }
    1231             : 
    1232             :     // Replace a use of the cmp with a use of the new cmp.
    1233        1759 :     TheUse = InsertedCmp;
    1234             :     MadeChange = true;
    1235             :     ++NumCmpUses;
    1236             :   }
    1237             : 
    1238             :   // If we removed all uses, nuke the cmp.
    1239      145167 :   if (CI->use_empty()) {
    1240         949 :     CI->eraseFromParent();
    1241             :     MadeChange = true;
    1242             :   }
    1243             : 
    1244             :   return MadeChange;
    1245             : }
    1246             : 
    1247      145212 : static bool OptimizeCmpExpression(CmpInst *CI, const TargetLowering *TLI) {
    1248      145212 :   if (SinkCmpExpression(CI, TLI))
    1249             :     return true;
    1250             : 
    1251      143764 :   if (CombineUAddWithOverflow(CI))
    1252          81 :     return true;
    1253             : 
    1254             :   return false;
    1255             : }
    1256             : 
    1257             : /// Duplicate and sink the given 'and' instruction into user blocks where it is
    1258             : /// used in a compare to allow isel to generate better code for targets where
    1259             : /// this operation can be combined.
    1260             : ///
    1261             : /// Return true if any changes are made.
    1262           0 : static bool sinkAndCmp0Expression(Instruction *AndI,
    1263             :                                   const TargetLowering &TLI,
    1264             :                                   SetOfInstrs &InsertedInsts) {
    1265             :   // Double-check that we're not trying to optimize an instruction that was
    1266             :   // already optimized by some other part of this pass.
    1267             :   assert(!InsertedInsts.count(AndI) &&
    1268             :          "Attempting to optimize already optimized and instruction");
    1269             :   (void) InsertedInsts;
    1270             : 
    1271             :   // Nothing to do for single use in same basic block.
    1272           0 :   if (AndI->hasOneUse() &&
    1273           0 :       AndI->getParent() == cast<Instruction>(*AndI->user_begin())->getParent())
    1274           0 :     return false;
    1275             : 
    1276             :   // Try to avoid cases where sinking/duplicating is likely to increase register
    1277             :   // pressure.
    1278           0 :   if (!isa<ConstantInt>(AndI->getOperand(0)) &&
    1279           0 :       !isa<ConstantInt>(AndI->getOperand(1)) &&
    1280           0 :       AndI->getOperand(0)->hasOneUse() && AndI->getOperand(1)->hasOneUse())
    1281           0 :     return false;
    1282             : 
    1283           0 :   for (auto *U : AndI->users()) {
    1284             :     Instruction *User = cast<Instruction>(U);
    1285             : 
    1286             :     // Only sink for and mask feeding icmp with 0.
    1287           0 :     if (!isa<ICmpInst>(User))
    1288           0 :       return false;
    1289             : 
    1290           0 :     auto *CmpC = dyn_cast<ConstantInt>(User->getOperand(1));
    1291           0 :     if (!CmpC || !CmpC->isZero())
    1292           0 :       return false;
    1293             :   }
    1294             : 
    1295           0 :   if (!TLI.isMaskAndCmp0FoldingBeneficial(*AndI))
    1296           0 :     return false;
    1297             : 
    1298             :   LLVM_DEBUG(dbgs() << "found 'and' feeding only icmp 0;\n");
    1299             :   LLVM_DEBUG(AndI->getParent()->dump());
    1300             : 
    1301             :   // Push the 'and' into the same block as the icmp 0.  There should only be
    1302             :   // one (icmp (and, 0)) in each block, since CSE/GVN should have removed any
    1303             :   // others, so we don't need to keep track of which BBs we insert into.
    1304             :   for (Value::user_iterator UI = AndI->user_begin(), E = AndI->user_end();
    1305           0 :        UI != E; ) {
    1306             :     Use &TheUse = UI.getUse();
    1307             :     Instruction *User = cast<Instruction>(*UI);
    1308             : 
    1309             :     // Preincrement use iterator so we don't invalidate it.
    1310             :     ++UI;
    1311             : 
    1312             :     LLVM_DEBUG(dbgs() << "sinking 'and' use: " << *User << "\n");
    1313             : 
    1314             :     // Keep the 'and' in the same place if the use is already in the same block.
    1315             :     Instruction *InsertPt =
    1316           0 :         User->getParent() == AndI->getParent() ? AndI : User;
    1317             :     Instruction *InsertedAnd =
    1318           0 :         BinaryOperator::Create(Instruction::And, AndI->getOperand(0),
    1319             :                                AndI->getOperand(1), "", InsertPt);
    1320             :     // Propagate the debug info.
    1321           0 :     InsertedAnd->setDebugLoc(AndI->getDebugLoc());
    1322             : 
    1323             :     // Replace a use of the 'and' with a use of the new 'and'.
    1324             :     TheUse = InsertedAnd;
    1325             :     ++NumAndUses;
    1326             :     LLVM_DEBUG(User->getParent()->dump());
    1327             :   }
    1328             : 
    1329             :   // We removed all uses, nuke the and.
    1330           0 :   AndI->eraseFromParent();
    1331           0 :   return true;
    1332             : }
    1333             : 
    1334             : /// Check if the candidates could be combined with a shift instruction, which
    1335             : /// includes:
    1336             : /// 1. Truncate instruction
    1337             : /// 2. And instruction and the imm is a mask of the low bits:
    1338             : /// imm & (imm+1) == 0
    1339        2432 : static bool isExtractBitsCandidateUse(Instruction *User) {
    1340        2432 :   if (!isa<TruncInst>(User)) {
    1341        1969 :     if (User->getOpcode() != Instruction::And ||
    1342         270 :         !isa<ConstantInt>(User->getOperand(1)))
    1343             :       return false;
    1344             : 
    1345             :     const APInt &Cimm = cast<ConstantInt>(User->getOperand(1))->getValue();
    1346             : 
    1347         260 :     if ((Cimm & (Cimm + 1)).getBoolValue())
    1348          15 :       return false;
    1349             :   }
    1350             :   return true;
    1351             : }
    1352             : 
    1353             : /// Sink both shift and truncate instruction to the use of truncate's BB.
    1354             : static bool
    1355          99 : SinkShiftAndTruncate(BinaryOperator *ShiftI, Instruction *User, ConstantInt *CI,
    1356             :                      DenseMap<BasicBlock *, BinaryOperator *> &InsertedShifts,
    1357             :                      const TargetLowering &TLI, const DataLayout &DL) {
    1358          99 :   BasicBlock *UserBB = User->getParent();
    1359             :   DenseMap<BasicBlock *, CastInst *> InsertedTruncs;
    1360             :   TruncInst *TruncI = dyn_cast<TruncInst>(User);
    1361             :   bool MadeChange = false;
    1362             : 
    1363             :   for (Value::user_iterator TruncUI = TruncI->user_begin(),
    1364             :                             TruncE = TruncI->user_end();
    1365         218 :        TruncUI != TruncE;) {
    1366             : 
    1367             :     Use &TruncTheUse = TruncUI.getUse();
    1368             :     Instruction *TruncUser = cast<Instruction>(*TruncUI);
    1369             :     // Preincrement use iterator so we don't invalidate it.
    1370             : 
    1371             :     ++TruncUI;
    1372             : 
    1373         238 :     int ISDOpcode = TLI.InstructionOpcodeToISD(TruncUser->getOpcode());
    1374         119 :     if (!ISDOpcode)
    1375         116 :       continue;
    1376             : 
    1377             :     // If the use is actually a legal node, there will not be an
    1378             :     // implicit truncate.
    1379             :     // FIXME: always querying the result type is just an
    1380             :     // approximation; some nodes' legality is determined by the
    1381             :     // operand or other means. There's no good way to find out though.
    1382         103 :     if (TLI.isOperationLegalOrCustom(
    1383             :             ISDOpcode, TLI.getValueType(DL, TruncUser->getType(), true)))
    1384             :       continue;
    1385             : 
    1386             :     // Don't bother for PHI nodes.
    1387          92 :     if (isa<PHINode>(TruncUser))
    1388             :       continue;
    1389             : 
    1390          92 :     BasicBlock *TruncUserBB = TruncUser->getParent();
    1391             : 
    1392          92 :     if (UserBB == TruncUserBB)
    1393             :       continue;
    1394             : 
    1395             :     BinaryOperator *&InsertedShift = InsertedShifts[TruncUserBB];
    1396             :     CastInst *&InsertedTrunc = InsertedTruncs[TruncUserBB];
    1397             : 
    1398           3 :     if (!InsertedShift && !InsertedTrunc) {
    1399           3 :       BasicBlock::iterator InsertPt = TruncUserBB->getFirstInsertionPt();
    1400             :       assert(InsertPt != TruncUserBB->end());
    1401             :       // Sink the shift
    1402           3 :       if (ShiftI->getOpcode() == Instruction::AShr)
    1403           0 :         InsertedShift = BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI,
    1404             :                                                    "", &*InsertPt);
    1405             :       else
    1406           3 :         InsertedShift = BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI,
    1407             :                                                    "", &*InsertPt);
    1408           3 :       InsertedShift->setDebugLoc(ShiftI->getDebugLoc());
    1409             : 
    1410             :       // Sink the trunc
    1411           3 :       BasicBlock::iterator TruncInsertPt = TruncUserBB->getFirstInsertionPt();
    1412             :       TruncInsertPt++;
    1413             :       assert(TruncInsertPt != TruncUserBB->end());
    1414             : 
    1415           6 :       InsertedTrunc = CastInst::Create(TruncI->getOpcode(), InsertedShift,
    1416             :                                        TruncI->getType(), "", &*TruncInsertPt);
    1417           3 :       InsertedTrunc->setDebugLoc(TruncI->getDebugLoc());
    1418             : 
    1419             :       MadeChange = true;
    1420             : 
    1421           3 :       TruncTheUse = InsertedTrunc;
    1422             :     }
    1423             :   }
    1424          99 :   return MadeChange;
    1425             : }
    1426             : 
    1427             : /// Sink the shift *right* instruction into user blocks if the uses could
    1428             : /// potentially be combined with this shift instruction and generate BitExtract
    1429             : /// instruction. It will only be applied if the architecture supports BitExtract
    1430             : /// instruction. Here is an example:
    1431             : /// BB1:
    1432             : ///   %x.extract.shift = lshr i64 %arg1, 32
    1433             : /// BB2:
    1434             : ///   %x.extract.trunc = trunc i64 %x.extract.shift to i16
    1435             : /// ==>
    1436             : ///
    1437             : /// BB2:
    1438             : ///   %x.extract.shift.1 = lshr i64 %arg1, 32
    1439             : ///   %x.extract.trunc = trunc i64 %x.extract.shift.1 to i16
    1440             : ///
    1441             : /// CodeGen will recognize the pattern in BB2 and generate BitExtract
    1442             : /// instruction.
    1443             : /// Return true if any changes are made.
    1444        1951 : static bool OptimizeExtractBits(BinaryOperator *ShiftI, ConstantInt *CI,
    1445             :                                 const TargetLowering &TLI,
    1446             :                                 const DataLayout &DL) {
    1447        1951 :   BasicBlock *DefBB = ShiftI->getParent();
    1448             : 
    1449             :   /// Only insert instructions in each block once.
    1450             :   DenseMap<BasicBlock *, BinaryOperator *> InsertedShifts;
    1451             : 
    1452        1951 :   bool shiftIsLegal = TLI.isTypeLegal(TLI.getValueType(DL, ShiftI->getType()));
    1453             : 
    1454             :   bool MadeChange = false;
    1455             :   for (Value::user_iterator UI = ShiftI->user_begin(), E = ShiftI->user_end();
    1456        4388 :        UI != E;) {
    1457             :     Use &TheUse = UI.getUse();
    1458             :     Instruction *User = cast<Instruction>(*UI);
    1459             :     // Preincrement use iterator so we don't invalidate it.
    1460             :     ++UI;
    1461             : 
    1462             :     // Don't bother for PHI nodes.
    1463        2437 :     if (isa<PHINode>(User))
    1464        2381 :       continue;
    1465             : 
    1466        2432 :     if (!isExtractBitsCandidateUse(User))
    1467             :       continue;
    1468             : 
    1469         978 :     BasicBlock *UserBB = User->getParent();
    1470             : 
    1471         978 :     if (UserBB == DefBB) {
    1472             :       // If the shift and truncate instruction are in the same BB. The use of
    1473             :       // the truncate(TruncUse) may still introduce another truncate if not
    1474             :       // legal. In this case, we would like to sink both shift and truncate
    1475             :       // instruction to the BB of TruncUse.
    1476             :       // for example:
    1477             :       // BB1:
    1478             :       // i64 shift.result = lshr i64 opnd, imm
    1479             :       // trunc.result = trunc shift.result to i16
    1480             :       //
    1481             :       // BB2:
    1482             :       //   ----> We will have an implicit truncate here if the architecture does
    1483             :       //   not have i16 compare.
    1484             :       // cmp i16 trunc.result, opnd2
    1485             :       //
    1486         729 :       if (isa<TruncInst>(User) && shiftIsLegal
    1487             :           // If the type of the truncate is legal, no truncate will be
    1488             :           // introduced in other basic blocks.
    1489         922 :           &&
    1490         692 :           (!TLI.isTypeLegal(TLI.getValueType(DL, User->getType()))))
    1491             :         MadeChange =
    1492          99 :             SinkShiftAndTruncate(ShiftI, User, CI, InsertedShifts, TLI, DL);
    1493             : 
    1494         922 :       continue;
    1495             :     }
    1496             :     // If we have already inserted a shift into this block, use it.
    1497             :     BinaryOperator *&InsertedShift = InsertedShifts[UserBB];
    1498             : 
    1499          56 :     if (!InsertedShift) {
    1500          56 :       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
    1501             :       assert(InsertPt != UserBB->end());
    1502             : 
    1503          56 :       if (ShiftI->getOpcode() == Instruction::AShr)
    1504           8 :         InsertedShift = BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI,
    1505             :                                                    "", &*InsertPt);
    1506             :       else
    1507          48 :         InsertedShift = BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI,
    1508             :                                                    "", &*InsertPt);
    1509         112 :       InsertedShift->setDebugLoc(ShiftI->getDebugLoc());
    1510             : 
    1511             :       MadeChange = true;
    1512             :     }
    1513             : 
    1514             :     // Replace a use of the shift with a use of the new shift.
    1515          56 :     TheUse = InsertedShift;
    1516             :   }
    1517             : 
    1518             :   // If we removed all uses, nuke the shift.
    1519        1951 :   if (ShiftI->use_empty()) {
    1520          26 :     salvageDebugInfo(*ShiftI);
    1521          26 :     ShiftI->eraseFromParent();
    1522             :   }
    1523             : 
    1524        1951 :   return MadeChange;
    1525             : }
    1526             : 
    1527             : /// If counting leading or trailing zeros is an expensive operation and a zero
    1528             : /// input is defined, add a check for zero to avoid calling the intrinsic.
    1529             : ///
    1530             : /// We want to transform:
    1531             : ///     %z = call i64 @llvm.cttz.i64(i64 %A, i1 false)
    1532             : ///
    1533             : /// into:
    1534             : ///   entry:
    1535             : ///     %cmpz = icmp eq i64 %A, 0
    1536             : ///     br i1 %cmpz, label %cond.end, label %cond.false
    1537             : ///   cond.false:
    1538             : ///     %z = call i64 @llvm.cttz.i64(i64 %A, i1 true)
    1539             : ///     br label %cond.end
    1540             : ///   cond.end:
    1541             : ///     %ctz = phi i64 [ 64, %entry ], [ %z, %cond.false ]
    1542             : ///
    1543             : /// If the transform is performed, return true and set ModifiedDT to true.
    1544        1827 : static bool despeculateCountZeros(IntrinsicInst *CountZeros,
    1545             :                                   const TargetLowering *TLI,
    1546             :                                   const DataLayout *DL,
    1547             :                                   bool &ModifiedDT) {
    1548        1827 :   if (!TLI || !DL)
    1549             :     return false;
    1550             : 
    1551             :   // If a zero input is undefined, it doesn't make sense to despeculate that.
    1552        3654 :   if (match(CountZeros->getOperand(1), m_One()))
    1553             :     return false;
    1554             : 
    1555             :   // If it's cheap to speculate, there's nothing to do.
    1556             :   auto IntrinsicID = CountZeros->getIntrinsicID();
    1557         814 :   if ((IntrinsicID == Intrinsic::cttz && TLI->isCheapToSpeculateCttz()) ||
    1558         457 :       (IntrinsicID == Intrinsic::ctlz && TLI->isCheapToSpeculateCtlz()))
    1559         305 :     return false;
    1560             : 
    1561             :   // Only handle legal scalar cases. Anything else requires too much work.
    1562         509 :   Type *Ty = CountZeros->getType();
    1563         509 :   unsigned SizeInBits = Ty->getPrimitiveSizeInBits();
    1564         509 :   if (Ty->isVectorTy() || SizeInBits > DL->getLargestLegalIntTypeSizeInBits())
    1565         478 :     return false;
    1566             : 
    1567             :   // The intrinsic will be sunk behind a compare against zero and branch.
    1568          31 :   BasicBlock *StartBlock = CountZeros->getParent();
    1569          31 :   BasicBlock *CallBlock = StartBlock->splitBasicBlock(CountZeros, "cond.false");
    1570             : 
    1571             :   // Create another block after the count zero intrinsic. A PHI will be added
    1572             :   // in this block to select the result of the intrinsic or the bit-width
    1573             :   // constant if the input to the intrinsic is zero.
    1574          31 :   BasicBlock::iterator SplitPt = ++(BasicBlock::iterator(CountZeros));
    1575          31 :   BasicBlock *EndBlock = CallBlock->splitBasicBlock(SplitPt, "cond.end");
    1576             : 
    1577             :   // Set up a builder to create a compare, conditional branch, and PHI.
    1578          31 :   IRBuilder<> Builder(CountZeros->getContext());
    1579          31 :   Builder.SetInsertPoint(StartBlock->getTerminator());
    1580          31 :   Builder.SetCurrentDebugLocation(CountZeros->getDebugLoc());
    1581             : 
    1582             :   // Replace the unconditional branch that was created by the first split with
    1583             :   // a compare against zero and a conditional branch.
    1584          31 :   Value *Zero = Constant::getNullValue(Ty);
    1585          31 :   Value *Cmp = Builder.CreateICmpEQ(CountZeros->getOperand(0), Zero, "cmpz");
    1586          31 :   Builder.CreateCondBr(Cmp, EndBlock, CallBlock);
    1587          31 :   StartBlock->getTerminator()->eraseFromParent();
    1588             : 
    1589             :   // Create a PHI in the end block to select either the output of the intrinsic
    1590             :   // or the bit width of the operand.
    1591          31 :   Builder.SetInsertPoint(&EndBlock->front());
    1592          31 :   PHINode *PN = Builder.CreatePHI(Ty, 2, "ctz");
    1593          31 :   CountZeros->replaceAllUsesWith(PN);
    1594          62 :   Value *BitWidth = Builder.getInt(APInt(SizeInBits, SizeInBits));
    1595          31 :   PN->addIncoming(BitWidth, StartBlock);
    1596          31 :   PN->addIncoming(CountZeros, CallBlock);
    1597             : 
    1598             :   // We are explicitly handling the zero case, so we can set the intrinsic's
    1599             :   // undefined zero argument to 'true'. This will also prevent reprocessing the
    1600             :   // intrinsic; we only despeculate when a zero input is defined.
    1601          31 :   CountZeros->setArgOperand(1, Builder.getTrue());
    1602          31 :   ModifiedDT = true;
    1603             :   return true;
    1604             : }
    1605             : 
    1606      666803 : bool CodeGenPrepare::optimizeCallInst(CallInst *CI, bool &ModifiedDT) {
    1607      666803 :   BasicBlock *BB = CI->getParent();
    1608             : 
    1609             :   // Lower inline assembly if we can.
    1610             :   // If we found an inline asm expession, and if the target knows how to
    1611             :   // lower it to normal LLVM code, do so now.
    1612      666803 :   if (TLI && isa<InlineAsm>(CI->getCalledValue())) {
    1613       14152 :     if (TLI->ExpandInlineAsm(CI)) {
    1614             :       // Avoid invalidating the iterator.
    1615          49 :       CurInstIterator = BB->begin();
    1616             :       // Avoid processing instructions out of order, which could cause
    1617             :       // reuse before a value is defined.
    1618             :       SunkAddrs.clear();
    1619          49 :       return true;
    1620             :     }
    1621             :     // Sink address computing for memory operands into the block.
    1622       14103 :     if (optimizeInlineAsmInst(CI))
    1623             :       return true;
    1624             :   }
    1625             : 
    1626             :   // Align the pointer arguments to this call if the target thinks it's a good
    1627             :   // idea
    1628             :   unsigned MinSize, PrefAlign;
    1629      666739 :   if (TLI && TLI->shouldAlignPointerArgs(CI, MinSize, PrefAlign)) {
    1630        3320 :     for (auto &Arg : CI->arg_operands()) {
    1631             :       // We want to align both objects whose address is used directly and
    1632             :       // objects whose address is used in casts and GEPs, though it only makes
    1633             :       // sense for GEPs if the offset is a multiple of the desired alignment and
    1634             :       // if size - offset meets the size threshold.
    1635        5312 :       if (!Arg->getType()->isPointerTy())
    1636        1548 :         continue;
    1637        1154 :       APInt Offset(DL->getIndexSizeInBits(
    1638             :                        cast<PointerType>(Arg->getType())->getAddressSpace()),
    1639             :                    0);
    1640        1154 :       Value *Val = Arg->stripAndAccumulateInBoundsConstantOffsets(*DL, Offset);
    1641             :       uint64_t Offset2 = Offset.getLimitedValue();
    1642        1154 :       if ((Offset2 & (PrefAlign-1)) != 0)
    1643             :         continue;
    1644             :       AllocaInst *AI;
    1645         149 :       if ((AI = dyn_cast<AllocaInst>(Val)) && AI->getAlignment() < PrefAlign &&
    1646         138 :           DL->getTypeAllocSize(AI->getAllocatedType()) >= MinSize + Offset2)
    1647          60 :         AI->setAlignment(PrefAlign);
    1648             :       // Global variables can only be aligned if they are defined in this
    1649             :       // object (i.e. they are uniquely initialized in this object), and
    1650             :       // over-aligning global variables that have an explicit section is
    1651             :       // forbidden.
    1652             :       GlobalVariable *GV;
    1653         214 :       if ((GV = dyn_cast<GlobalVariable>(Val)) && GV->canIncreaseAlignment() &&
    1654          82 :           GV->getPointerAlignment(*DL) < PrefAlign &&
    1655          67 :           DL->getTypeAllocSize(GV->getValueType()) >=
    1656          67 :               MinSize + Offset2)
    1657          39 :         GV->setAlignment(PrefAlign);
    1658             :     }
    1659             :     // If this is a memcpy (or similar) then we may be able to improve the
    1660             :     // alignment
    1661             :     if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(CI)) {
    1662         664 :       unsigned DestAlign = getKnownAlignment(MI->getDest(), *DL);
    1663         664 :       if (DestAlign > MI->getDestAlignment())
    1664         454 :         MI->setDestAlignment(DestAlign);
    1665             :       if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) {
    1666         490 :         unsigned SrcAlign = getKnownAlignment(MTI->getSource(), *DL);
    1667         490 :         if (SrcAlign > MTI->getSourceAlignment())
    1668         329 :           MTI->setSourceAlignment(SrcAlign);
    1669             :       }
    1670             :     }
    1671             :   }
    1672             : 
    1673             :   // If we have a cold call site, try to sink addressing computation into the
    1674             :   // cold block.  This interacts with our handling for loads and stores to
    1675             :   // ensure that we can fold all uses of a potential addressing computation
    1676             :   // into their uses.  TODO: generalize this to work over profiling data
    1677      666739 :   if (!OptSize && CI->hasFnAttr(Attribute::Cold))
    1678         137 :     for (auto &Arg : CI->arg_operands()) {
    1679         250 :       if (!Arg->getType()->isPointerTy())
    1680             :         continue;
    1681             :       unsigned AS = Arg->getType()->getPointerAddressSpace();
    1682         113 :       return optimizeMemoryInst(CI, Arg, Arg->getType(), AS);
    1683             :     }
    1684             : 
    1685             :   IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
    1686             :   if (II) {
    1687      502386 :     switch (II->getIntrinsicID()) {
    1688             :     default: break;
    1689          34 :     case Intrinsic::objectsize: {
    1690             :       // Lower all uses of llvm.objectsize.*
    1691             :       ConstantInt *RetVal =
    1692          34 :           lowerObjectSizeCall(II, *DL, TLInfo, /*MustSucceed=*/true);
    1693             :       // Substituting this can cause recursive simplifications, which can
    1694             :       // invalidate our iterator.  Use a WeakTrackingVH to hold onto it in case
    1695             :       // this
    1696             :       // happens.
    1697          34 :       Value *CurValue = &*CurInstIterator;
    1698             :       WeakTrackingVH IterHandle(CurValue);
    1699             : 
    1700          34 :       replaceAndRecursivelySimplify(CI, RetVal, TLInfo, nullptr);
    1701             : 
    1702             :       // If the iterator instruction was recursively deleted, start over at the
    1703             :       // start of the block.
    1704          34 :       if (IterHandle != CurValue) {
    1705           4 :         CurInstIterator = BB->begin();
    1706             :         SunkAddrs.clear();
    1707             :       }
    1708             :       return true;
    1709             :     }
    1710         114 :     case Intrinsic::aarch64_stlxr:
    1711             :     case Intrinsic::aarch64_stxr: {
    1712         114 :       ZExtInst *ExtVal = dyn_cast<ZExtInst>(CI->getArgOperand(0));
    1713          87 :       if (!ExtVal || !ExtVal->hasOneUse() ||
    1714          87 :           ExtVal->getParent() == CI->getParent())
    1715             :         return false;
    1716             :       // Sink a zext feeding stlxr/stxr before it, so it can be folded into it.
    1717           1 :       ExtVal->moveBefore(CI);
    1718             :       // Mark this instruction as "inserted by CGP", so that other
    1719             :       // optimizations don't touch it.
    1720           1 :       InsertedInsts.insert(ExtVal);
    1721           1 :       return true;
    1722             :     }
    1723           4 :     case Intrinsic::launder_invariant_group:
    1724             :     case Intrinsic::strip_invariant_group:
    1725           4 :       II->replaceAllUsesWith(II->getArgOperand(0));
    1726           4 :       II->eraseFromParent();
    1727           4 :       return true;
    1728             : 
    1729        1827 :     case Intrinsic::cttz:
    1730             :     case Intrinsic::ctlz:
    1731             :       // If counting zeros is expensive, try to avoid it.
    1732        1827 :       return despeculateCountZeros(II, TLI, DL, ModifiedDT);
    1733             :     }
    1734             : 
    1735      500407 :     if (TLI) {
    1736             :       SmallVector<Value*, 2> PtrOps;
    1737             :       Type *AccessTy;
    1738      500406 :       if (TLI->getAddrModeArguments(II, PtrOps, AccessTy))
    1739         522 :         while (!PtrOps.empty()) {
    1740             :           Value *PtrVal = PtrOps.pop_back_val();
    1741         269 :           unsigned AS = PtrVal->getType()->getPointerAddressSpace();
    1742         269 :           if (optimizeMemoryInst(II, PtrVal, AccessTy, AS))
    1743             :             return true;
    1744             :         }
    1745             :     }
    1746             :   }
    1747             : 
    1748             :   // From here on out we're working with named functions.
    1749             :   if (!CI->getCalledFunction()) return false;
    1750             : 
    1751             :   // Lower all default uses of _chk calls.  This is very similar
    1752             :   // to what InstCombineCalls does, but here we are only lowering calls
    1753             :   // to fortified library functions (e.g. __memcpy_chk) that have the default
    1754             :   // "don't know" as the objectsize.  Anything else should be left alone.
    1755      635068 :   FortifiedLibCallSimplifier Simplifier(TLInfo, true);
    1756      635068 :   if (Value *V = Simplifier.optimizeCall(CI)) {
    1757          38 :     CI->replaceAllUsesWith(V);
    1758          38 :     CI->eraseFromParent();
    1759          38 :     return true;
    1760             :   }
    1761             : 
    1762             :   return false;
    1763             : }
    1764             : 
    1765             : /// Look for opportunities to duplicate return instructions to the predecessor
    1766             : /// to enable tail call optimizations. The case it is currently looking for is:
    1767             : /// @code
    1768             : /// bb0:
    1769             : ///   %tmp0 = tail call i32 @f0()
    1770             : ///   br label %return
    1771             : /// bb1:
    1772             : ///   %tmp1 = tail call i32 @f1()
    1773             : ///   br label %return
    1774             : /// bb2:
    1775             : ///   %tmp2 = tail call i32 @f2()
    1776             : ///   br label %return
    1777             : /// return:
    1778             : ///   %retval = phi i32 [ %tmp0, %bb0 ], [ %tmp1, %bb1 ], [ %tmp2, %bb2 ]
    1779             : ///   ret i32 %retval
    1780             : /// @endcode
    1781             : ///
    1782             : /// =>
    1783             : ///
    1784             : /// @code
    1785             : /// bb0:
    1786             : ///   %tmp0 = tail call i32 @f0()
    1787             : ///   ret i32 %tmp0
    1788             : /// bb1:
    1789             : ///   %tmp1 = tail call i32 @f1()
    1790             : ///   ret i32 %tmp1
    1791             : /// bb2:
    1792             : ///   %tmp2 = tail call i32 @f2()
    1793             : ///   ret i32 %tmp2
    1794             : /// @endcode
    1795           0 : bool CodeGenPrepare::dupRetToEnableTailCallOpts(BasicBlock *BB) {
    1796           0 :   if (!TLI)
    1797           0 :     return false;
    1798             : 
    1799             :   ReturnInst *RetI = dyn_cast<ReturnInst>(BB->getTerminator());
    1800             :   if (!RetI)
    1801           0 :     return false;
    1802             : 
    1803             :   PHINode *PN = nullptr;
    1804             :   BitCastInst *BCI = nullptr;
    1805             :   Value *V = RetI->getReturnValue();
    1806             :   if (V) {
    1807             :     BCI = dyn_cast<BitCastInst>(V);
    1808             :     if (BCI)
    1809             :       V = BCI->getOperand(0);
    1810             : 
    1811             :     PN = dyn_cast<PHINode>(V);
    1812             :     if (!PN)
    1813           0 :       return false;
    1814             :   }
    1815             : 
    1816           0 :   if (PN && PN->getParent() != BB)
    1817           0 :     return false;
    1818             : 
    1819             :   // Make sure there are no instructions between the PHI and return, or that the
    1820             :   // return is the first instruction in the block.
    1821           0 :   if (PN) {
    1822           0 :     BasicBlock::iterator BI = BB->begin();
    1823           0 :     do { ++BI; } while (isa<DbgInfoIntrinsic>(BI));
    1824           0 :     if (&*BI == BCI)
    1825             :       // Also skip over the bitcast.
    1826             :       ++BI;
    1827           0 :     if (&*BI != RetI)
    1828           0 :       return false;
    1829             :   } else {
    1830           0 :     BasicBlock::iterator BI = BB->begin();
    1831           0 :     while (isa<DbgInfoIntrinsic>(BI)) ++BI;
    1832           0 :     if (&*BI != RetI)
    1833           0 :       return false;
    1834             :   }
    1835             : 
    1836             :   /// Only dup the ReturnInst if the CallInst is likely to be emitted as a tail
    1837             :   /// call.
    1838           0 :   const Function *F = BB->getParent();
    1839             :   SmallVector<CallInst*, 4> TailCalls;
    1840           0 :   if (PN) {
    1841           0 :     for (unsigned I = 0, E = PN->getNumIncomingValues(); I != E; ++I) {
    1842           0 :       CallInst *CI = dyn_cast<CallInst>(PN->getIncomingValue(I));
    1843             :       // Make sure the phi value is indeed produced by the tail call.
    1844           0 :       if (CI && CI->hasOneUse() && CI->getParent() == PN->getIncomingBlock(I) &&
    1845           0 :           TLI->mayBeEmittedAsTailCall(CI) &&
    1846           0 :           attributesPermitTailCall(F, CI, RetI, *TLI))
    1847           0 :         TailCalls.push_back(CI);
    1848             :     }
    1849             :   } else {
    1850             :     SmallPtrSet<BasicBlock*, 4> VisitedBBs;
    1851           0 :     for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB); PI != PE; ++PI) {
    1852           0 :       if (!VisitedBBs.insert(*PI).second)
    1853           0 :         continue;
    1854             : 
    1855             :       BasicBlock::InstListType &InstList = (*PI)->getInstList();
    1856             :       BasicBlock::InstListType::reverse_iterator RI = InstList.rbegin();
    1857             :       BasicBlock::InstListType::reverse_iterator RE = InstList.rend();
    1858           0 :       do { ++RI; } while (RI != RE && isa<DbgInfoIntrinsic>(&*RI));
    1859           0 :       if (RI == RE)
    1860           0 :         continue;
    1861             : 
    1862           0 :       CallInst *CI = dyn_cast<CallInst>(&*RI);
    1863           0 :       if (CI && CI->use_empty() && TLI->mayBeEmittedAsTailCall(CI) &&
    1864           0 :           attributesPermitTailCall(F, CI, RetI, *TLI))
    1865           0 :         TailCalls.push_back(CI);
    1866             :     }
    1867             :   }
    1868             : 
    1869             :   bool Changed = false;
    1870           0 :   for (unsigned i = 0, e = TailCalls.size(); i != e; ++i) {
    1871           0 :     CallInst *CI = TailCalls[i];
    1872             :     CallSite CS(CI);
    1873             : 
    1874             :     // Make sure the call instruction is followed by an unconditional branch to
    1875             :     // the return block.
    1876           0 :     BasicBlock *CallBB = CI->getParent();
    1877             :     BranchInst *BI = dyn_cast<BranchInst>(CallBB->getTerminator());
    1878           0 :     if (!BI || !BI->isUnconditional() || BI->getSuccessor(0) != BB)
    1879           0 :       continue;
    1880             : 
    1881             :     // Duplicate the return into CallBB.
    1882           0 :     (void)FoldReturnIntoUncondBranch(RetI, BB, CallBB);
    1883           0 :     ModifiedDT = Changed = true;
    1884             :     ++NumRetsDup;
    1885             :   }
    1886             : 
    1887             :   // If we eliminated all predecessors of the block, delete the block now.
    1888           0 :   if (Changed && !BB->hasAddressTaken() && pred_begin(BB) == pred_end(BB))
    1889           0 :     BB->eraseFromParent();
    1890             : 
    1891             :   return Changed;
    1892             : }
    1893             : 
    1894             : //===----------------------------------------------------------------------===//
    1895             : // Memory Optimization
    1896             : //===----------------------------------------------------------------------===//
    1897             : 
    1898             : namespace {
    1899             : 
    1900             : /// This is an extended version of TargetLowering::AddrMode
    1901             : /// which holds actual Value*'s for register values.
    1902             : struct ExtAddrMode : public TargetLowering::AddrMode {
    1903             :   Value *BaseReg = nullptr;
    1904             :   Value *ScaledReg = nullptr;
    1905             :   Value *OriginalValue = nullptr;
    1906             : 
    1907             :   enum FieldName {
    1908             :     NoField        = 0x00,
    1909             :     BaseRegField   = 0x01,
    1910             :     BaseGVField    = 0x02,
    1911             :     BaseOffsField  = 0x04,
    1912             :     ScaledRegField = 0x08,
    1913             :     ScaleField     = 0x10,
    1914             :     MultipleFields = 0xff
    1915             :   };
    1916             : 
    1917             :   ExtAddrMode() = default;
    1918             : 
    1919             :   void print(raw_ostream &OS) const;
    1920             :   void dump() const;
    1921             : 
    1922      201084 :   FieldName compare(const ExtAddrMode &other) {
    1923             :     // First check that the types are the same on each field, as differing types
    1924             :     // is something we can't cope with later on.
    1925      201084 :     if (BaseReg && other.BaseReg &&
    1926      111802 :         BaseReg->getType() != other.BaseReg->getType())
    1927             :       return MultipleFields;
    1928      199443 :     if (BaseGV && other.BaseGV &&
    1929             :         BaseGV->getType() != other.BaseGV->getType())
    1930             :       return MultipleFields;
    1931      199401 :     if (ScaledReg && other.ScaledReg &&
    1932          52 :         ScaledReg->getType() != other.ScaledReg->getType())
    1933             :       return MultipleFields;
    1934             : 
    1935             :     // Check each field to see if it differs.
    1936             :     unsigned Result = NoField;
    1937      199401 :     if (BaseReg != other.BaseReg)
    1938             :       Result |= BaseRegField;
    1939      199401 :     if (BaseGV != other.BaseGV)
    1940         154 :       Result |= BaseGVField;
    1941      199401 :     if (BaseOffs != other.BaseOffs)
    1942      196514 :       Result |= BaseOffsField;
    1943      199401 :     if (ScaledReg != other.ScaledReg)
    1944         513 :       Result |= ScaledRegField;
    1945             :     // Don't count 0 as being a different scale, because that actually means
    1946             :     // unscaled (which will already be counted by having no ScaledReg).
    1947      199401 :     if (Scale && other.Scale && Scale != other.Scale)
    1948           1 :       Result |= ScaleField;
    1949             : 
    1950      199401 :     if (countPopulation(Result) > 1)
    1951             :       return MultipleFields;
    1952             :     else
    1953      196440 :       return static_cast<FieldName>(Result);
    1954             :   }
    1955             : 
    1956             :   // An AddrMode is trivial if it involves no calculation i.e. it is just a base
    1957             :   // with no offset.
    1958             :   bool isTrivial() {
    1959             :     // An AddrMode is (BaseGV + BaseReg + BaseOffs + ScaleReg * Scale) so it is
    1960             :     // trivial if at most one of these terms is nonzero, except that BaseGV and
    1961             :     // BaseReg both being zero actually means a null pointer value, which we
    1962             :     // consider to be 'non-zero' here.
    1963     1720320 :     return !BaseOffs && !Scale && !(BaseGV && BaseReg);
    1964             :   }
    1965             : 
    1966      342487 :   Value *GetFieldAsValue(FieldName Field, Type *IntPtrTy) {
    1967      342487 :     switch (Field) {
    1968             :     default:
    1969             :       return nullptr;
    1970         712 :     case BaseRegField:
    1971         712 :       return BaseReg;
    1972         160 :     case BaseGVField:
    1973         160 :       return BaseGV;
    1974          84 :     case ScaledRegField:
    1975          84 :       return ScaledReg;
    1976      341531 :     case BaseOffsField:
    1977      341531 :       return ConstantInt::get(IntPtrTy, BaseOffs);
    1978             :     }
    1979             :   }
    1980             : 
    1981          73 :   void SetCombinedField(FieldName Field, Value *V,
    1982             :                         const SmallVectorImpl<ExtAddrMode> &AddrModes) {
    1983          73 :     switch (Field) {
    1984           0 :     default:
    1985           0 :       llvm_unreachable("Unhandled fields are expected to be rejected earlier");
    1986             :       break;
    1987          49 :     case ExtAddrMode::BaseRegField:
    1988          49 :       BaseReg = V;
    1989          49 :       break;
    1990           0 :     case ExtAddrMode::BaseGVField:
    1991             :       // A combined BaseGV is an Instruction, not a GlobalValue, so it goes
    1992             :       // in the BaseReg field.
    1993             :       assert(BaseReg == nullptr);
    1994           0 :       BaseReg = V;
    1995           0 :       BaseGV = nullptr;
    1996           0 :       break;
    1997           5 :     case ExtAddrMode::ScaledRegField:
    1998           5 :       ScaledReg = V;
    1999             :       // If we have a mix of scaled and unscaled addrmodes then we want scale
    2000             :       // to be the scale and not zero.
    2001           5 :       if (!Scale)
    2002           4 :         for (const ExtAddrMode &AM : AddrModes)
    2003           4 :           if (AM.Scale) {
    2004           2 :             Scale = AM.Scale;
    2005           2 :             break;
    2006             :           }
    2007             :       break;
    2008          19 :     case ExtAddrMode::BaseOffsField:
    2009             :       // The offset is no longer a constant, so it goes in ScaledReg with a
    2010             :       // scale of 1.
    2011             :       assert(ScaledReg == nullptr);
    2012          19 :       ScaledReg = V;
    2013          19 :       Scale = 1;
    2014          19 :       BaseOffs = 0;
    2015          19 :       break;
    2016             :     }
    2017          73 :   }
    2018             : };
    2019             : 
    2020             : } // end anonymous namespace
    2021             : 
    2022             : #ifndef NDEBUG
    2023             : static inline raw_ostream &operator<<(raw_ostream &OS, const ExtAddrMode &AM) {
    2024             :   AM.print(OS);
    2025             :   return OS;
    2026             : }
    2027             : #endif
    2028             : 
    2029             : #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
    2030             : void ExtAddrMode::print(raw_ostream &OS) const {
    2031             :   bool NeedPlus = false;
    2032             :   OS << "[";
    2033             :   if (BaseGV) {
    2034             :     OS << (NeedPlus ? " + " : "")
    2035             :        << "GV:";
    2036             :     BaseGV->printAsOperand(OS, /*PrintType=*/false);
    2037             :     NeedPlus = true;
    2038             :   }
    2039             : 
    2040             :   if (BaseOffs) {
    2041             :     OS << (NeedPlus ? " + " : "")
    2042             :        << BaseOffs;
    2043             :     NeedPlus = true;
    2044             :   }
    2045             : 
    2046             :   if (BaseReg) {
    2047             :     OS << (NeedPlus ? " + " : "")
    2048             :        << "Base:";
    2049             :     BaseReg->printAsOperand(OS, /*PrintType=*/false);
    2050             :     NeedPlus = true;
    2051             :   }
    2052             :   if (Scale) {
    2053             :     OS << (NeedPlus ? " + " : "")
    2054             :        << Scale << "*";
    2055             :     ScaledReg->printAsOperand(OS, /*PrintType=*/false);
    2056             :   }
    2057             : 
    2058             :   OS << ']';
    2059             : }
    2060             : 
    2061             : LLVM_DUMP_METHOD void ExtAddrMode::dump() const {
    2062             :   print(dbgs());
    2063             :   dbgs() << '\n';
    2064             : }
    2065             : #endif
    2066             : 
    2067             : namespace {
    2068             : 
    2069             : /// This class provides transaction based operation on the IR.
    2070             : /// Every change made through this class is recorded in the internal state and
    2071             : /// can be undone (rollback) until commit is called.
    2072     1758953 : class TypePromotionTransaction {
    2073             :   /// This represents the common interface of the individual transaction.
    2074             :   /// Each class implements the logic for doing one specific modification on
    2075             :   /// the IR via the TypePromotionTransaction.
    2076             :   class TypePromotionAction {
    2077             :   protected:
    2078             :     /// The Instruction modified.
    2079             :     Instruction *Inst;
    2080             : 
    2081             :   public:
    2082             :     /// Constructor of the action.
    2083             :     /// The constructor performs the related action on the IR.
    2084       16151 :     TypePromotionAction(Instruction *Inst) : Inst(Inst) {}
    2085             : 
    2086             :     virtual ~TypePromotionAction() = default;
    2087             : 
    2088             :     /// Undo the modification done by this action.
    2089             :     /// When this method is called, the IR must be in the same state as it was
    2090             :     /// before this action was applied.
    2091             :     /// \pre Undoing the action works if and only if the IR is in the exact same
    2092             :     /// state as it was directly after this action was applied.
    2093             :     virtual void undo() = 0;
    2094             : 
    2095             :     /// Advocate every change made by this action.
    2096             :     /// When the results on the IR of the action are to be kept, it is important
    2097             :     /// to call this function, otherwise hidden information may be kept forever.
    2098           0 :     virtual void commit() {
    2099             :       // Nothing to be done, this action is not doing anything.
    2100           0 :     }
    2101             :   };
    2102             : 
    2103             :   /// Utility to remember the position of an instruction.
    2104             :   class InsertionHandler {
    2105             :     /// Position of an instruction.
    2106             :     /// Either an instruction:
    2107             :     /// - Is the first in a basic block: BB is used.
    2108             :     /// - Has a previous instruction: PrevInst is used.
    2109             :     union {
    2110             :       Instruction *PrevInst;
    2111             :       BasicBlock *BB;
    2112             :     } Point;
    2113             : 
    2114             :     /// Remember whether or not the instruction had a previous instruction.
    2115             :     bool HasPrevInstruction;
    2116             : 
    2117             :   public:
    2118             :     /// Record the position of \p Inst.
    2119        3008 :     InsertionHandler(Instruction *Inst) {
    2120        3008 :       BasicBlock::iterator It = Inst->getIterator();
    2121        6016 :       HasPrevInstruction = (It != (Inst->getParent()->begin()));
    2122        3008 :       if (HasPrevInstruction)
    2123        2907 :         Point.PrevInst = &*--It;
    2124             :       else
    2125         101 :         Point.BB = Inst->getParent();
    2126             :     }
    2127             : 
    2128             :     /// Insert \p Inst at the recorded position.
    2129           0 :     void insert(Instruction *Inst) {
    2130           0 :       if (HasPrevInstruction) {
    2131           0 :         if (Inst->getParent())
    2132           0 :           Inst->removeFromParent();
    2133           0 :         Inst->insertAfter(Point.PrevInst);
    2134             :       } else {
    2135           0 :         Instruction *Position = &*Point.BB->getFirstInsertionPt();
    2136           0 :         if (Inst->getParent())
    2137           0 :           Inst->moveBefore(Position);
    2138             :         else
    2139           0 :           Inst->insertBefore(Position);
    2140             :       }
    2141           0 :     }
    2142             :   };
    2143             : 
    2144             :   /// Move an instruction before another.
    2145           0 :   class InstructionMoveBefore : public TypePromotionAction {
    2146             :     /// Original position of the instruction.
    2147             :     InsertionHandler Position;
    2148             : 
    2149             :   public:
    2150             :     /// Move \p Inst before \p Before.
    2151        2513 :     InstructionMoveBefore(Instruction *Inst, Instruction *Before)
    2152        2513 :         : TypePromotionAction(Inst), Position(Inst) {
    2153             :       LLVM_DEBUG(dbgs() << "Do: move: " << *Inst << "\nbefore: " << *Before
    2154             :                         << "\n");
    2155        2513 :       Inst->moveBefore(Before);
    2156        2513 :     }
    2157             : 
    2158             :     /// Move the instruction back to its original position.
    2159        1125 :     void undo() override {
    2160             :       LLVM_DEBUG(dbgs() << "Undo: moveBefore: " << *Inst << "\n");
    2161        1125 :       Position.insert(Inst);
    2162        1125 :     }
    2163             :   };
    2164             : 
    2165             :   /// Set the operand of an instruction with a new value.
    2166           0 :   class OperandSetter : public TypePromotionAction {
    2167             :     /// Original operand of the instruction.
    2168             :     Value *Origin;
    2169             : 
    2170             :     /// Index of the modified instruction.
    2171             :     unsigned Idx;
    2172             : 
    2173             :   public:
    2174             :     /// Set \p Idx operand of \p Inst with \p NewVal.
    2175        7083 :     OperandSetter(Instruction *Inst, unsigned Idx, Value *NewVal)
    2176       14166 :         : TypePromotionAction(Inst), Idx(Idx) {
    2177             :       LLVM_DEBUG(dbgs() << "Do: setOperand: " << Idx << "\n"
    2178             :                         << "for:" << *Inst << "\n"
    2179             :                         << "with:" << *NewVal << "\n");
    2180        7083 :       Origin = Inst->getOperand(Idx);
    2181        7083 :       Inst->setOperand(Idx, NewVal);
    2182        7083 :     }
    2183             : 
    2184             :     /// Restore the original value of the instruction.
    2185        3144 :     void undo() override {
    2186             :       LLVM_DEBUG(dbgs() << "Undo: setOperand:" << Idx << "\n"
    2187             :                         << "for: " << *Inst << "\n"
    2188             :                         << "with: " << *Origin << "\n");
    2189        3144 :       Inst->setOperand(Idx, Origin);
    2190        3144 :     }
    2191             :   };
    2192             : 
    2193             :   /// Hide the operands of an instruction.
    2194             :   /// Do as if this instruction was not using any of its operands.
    2195         495 :   class OperandsHider : public TypePromotionAction {
    2196             :     /// The list of original operands.
    2197             :     SmallVector<Value *, 4> OriginalValues;
    2198             : 
    2199             :   public:
    2200             :     /// Remove \p Inst from the uses of the operands of \p Inst.
    2201         495 :     OperandsHider(Instruction *Inst) : TypePromotionAction(Inst) {
    2202             :       LLVM_DEBUG(dbgs() << "Do: OperandsHider: " << *Inst << "\n");
    2203             :       unsigned NumOpnds = Inst->getNumOperands();
    2204         495 :       OriginalValues.reserve(NumOpnds);
    2205         990 :       for (unsigned It = 0; It < NumOpnds; ++It) {
    2206             :         // Save the current operand.
    2207         495 :         Value *Val = Inst->getOperand(It);
    2208         495 :         OriginalValues.push_back(Val);
    2209             :         // Set a dummy one.
    2210             :         // We could use OperandSetter here, but that would imply an overhead
    2211             :         // that we are not willing to pay.
    2212         495 :         Inst->setOperand(It, UndefValue::get(Val->getType()));
    2213             :       }
    2214         495 :     }
    2215             : 
    2216             :     /// Restore the original list of uses.
    2217         160 :     void undo() override {
    2218             :       LLVM_DEBUG(dbgs() << "Undo: OperandsHider: " << *Inst << "\n");
    2219         320 :       for (unsigned It = 0, EndIt = OriginalValues.size(); It != EndIt; ++It)
    2220         320 :         Inst->setOperand(It, OriginalValues[It]);
    2221         160 :     }
    2222             :   };
    2223             : 
    2224             :   /// Build a truncate instruction.
    2225           0 :   class TruncBuilder : public TypePromotionAction {
    2226             :     Value *Val;
    2227             : 
    2228             :   public:
    2229             :     /// Build a truncate instruction of \p Opnd producing a \p Ty
    2230             :     /// result.
    2231             :     /// trunc Opnd to Ty.
    2232         173 :     TruncBuilder(Instruction *Opnd, Type *Ty) : TypePromotionAction(Opnd) {
    2233         173 :       IRBuilder<> Builder(Opnd);
    2234         173 :       Val = Builder.CreateTrunc(Opnd, Ty, "promoted");
    2235             :       LLVM_DEBUG(dbgs() << "Do: TruncBuilder: " << *Val << "\n");
    2236         173 :     }
    2237             : 
    2238             :     /// Get the built value.
    2239           0 :     Value *getBuiltValue() { return Val; }
    2240             : 
    2241             :     /// Remove the built instruction.
    2242          79 :     void undo() override {
    2243             :       LLVM_DEBUG(dbgs() << "Undo: TruncBuilder: " << *Val << "\n");
    2244          79 :       if (Instruction *IVal = dyn_cast<Instruction>(Val))
    2245          79 :         IVal->eraseFromParent();
    2246          79 :     }
    2247             :   };
    2248             : 
    2249             :   /// Build a sign extension instruction.
    2250           0 :   class SExtBuilder : public TypePromotionAction {
    2251             :     Value *Val;
    2252             : 
    2253             :   public:
    2254             :     /// Build a sign extension instruction of \p Opnd producing a \p Ty
    2255             :     /// result.
    2256             :     /// sext Opnd to Ty.
    2257         103 :     SExtBuilder(Instruction *InsertPt, Value *Opnd, Type *Ty)
    2258         103 :         : TypePromotionAction(InsertPt) {
    2259         103 :       IRBuilder<> Builder(InsertPt);
    2260         103 :       Val = Builder.CreateSExt(Opnd, Ty, "promoted");
    2261             :       LLVM_DEBUG(dbgs() << "Do: SExtBuilder: " << *Val << "\n");
    2262         103 :     }
    2263             : 
    2264             :     /// Get the built value.
    2265           0 :     Value *getBuiltValue() { return Val; }
    2266             : 
    2267             :     /// Remove the built instruction.
    2268          60 :     void undo() override {
    2269             :       LLVM_DEBUG(dbgs() << "Undo: SExtBuilder: " << *Val << "\n");
    2270          60 :       if (Instruction *IVal = dyn_cast<Instruction>(Val))
    2271          60 :         IVal->eraseFromParent();
    2272          60 :     }
    2273             :   };
    2274             : 
    2275             :   /// Build a zero extension instruction.
    2276           0 :   class ZExtBuilder : public TypePromotionAction {
    2277             :     Value *Val;
    2278             : 
    2279             :   public:
    2280             :     /// Build a zero extension instruction of \p Opnd producing a \p Ty
    2281             :     /// result.
    2282             :     /// zext Opnd to Ty.
    2283         494 :     ZExtBuilder(Instruction *InsertPt, Value *Opnd, Type *Ty)
    2284         494 :         : TypePromotionAction(InsertPt) {
    2285         494 :       IRBuilder<> Builder(InsertPt);
    2286         494 :       Val = Builder.CreateZExt(Opnd, Ty, "promoted");
    2287             :       LLVM_DEBUG(dbgs() << "Do: ZExtBuilder: " << *Val << "\n");
    2288         494 :     }
    2289             : 
    2290             :     /// Get the built value.
    2291           0 :     Value *getBuiltValue() { return Val; }
    2292             : 
    2293             :     /// Remove the built instruction.
    2294         162 :     void undo() override {
    2295             :       LLVM_DEBUG(dbgs() << "Undo: ZExtBuilder: " << *Val << "\n");
    2296         162 :       if (Instruction *IVal = dyn_cast<Instruction>(Val))
    2297         161 :         IVal->eraseFromParent();
    2298         162 :     }
    2299             :   };
    2300             : 
    2301             :   /// Mutate an instruction to another type.
    2302           0 :   class TypeMutator : public TypePromotionAction {
    2303             :     /// Record the original type.
    2304             :     Type *OrigTy;
    2305             : 
    2306             :   public:
    2307             :     /// Mutate the type of \p Inst into \p NewTy.
    2308             :     TypeMutator(Instruction *Inst, Type *NewTy)
    2309        2169 :         : TypePromotionAction(Inst), OrigTy(Inst->getType()) {
    2310             :       LLVM_DEBUG(dbgs() << "Do: MutateType: " << *Inst << " with " << *NewTy
    2311             :                         << "\n");
    2312             :       Inst->mutateType(NewTy);
    2313             :     }
    2314             : 
    2315             :     /// Mutate the instruction back to its original type.
    2316         946 :     void undo() override {
    2317             :       LLVM_DEBUG(dbgs() << "Undo: MutateType: " << *Inst << " with " << *OrigTy
    2318             :                         << "\n");
    2319         946 :       Inst->mutateType(OrigTy);
    2320         946 :     }
    2321             :   };
    2322             : 
    2323             :   /// Replace the uses of an instruction by another instruction.
    2324          37 :   class UsesReplacer : public TypePromotionAction {
    2325             :     /// Helper structure to keep track of the replaced uses.
    2326             :     struct InstructionAndIdx {
    2327             :       /// The instruction using the instruction.
    2328             :       Instruction *Inst;
    2329             : 
    2330             :       /// The index where this instruction is used for Inst.
    2331             :       unsigned Idx;
    2332             : 
    2333             :       InstructionAndIdx(Instruction *Inst, unsigned Idx)
    2334        3562 :           : Inst(Inst), Idx(Idx) {}
    2335             :     };
    2336             : 
    2337             :     /// Keep track of the original uses (pair Instruction, Index).
    2338             :     SmallVector<InstructionAndIdx, 4> OriginalUses;
    2339             : 
    2340             :     using use_iterator = SmallVectorImpl<InstructionAndIdx>::iterator;
    2341             : 
    2342             :   public:
    2343             :     /// Replace all the use of \p Inst by \p New.
    2344        2626 :     UsesReplacer(Instruction *Inst, Value *New) : TypePromotionAction(Inst) {
    2345             :       LLVM_DEBUG(dbgs() << "Do: UsersReplacer: " << *Inst << " with " << *New
    2346             :                         << "\n");
    2347             :       // Record the original uses.
    2348        6188 :       for (Use &U : Inst->uses()) {
    2349        3562 :         Instruction *UserI = cast<Instruction>(U.getUser());
    2350        3562 :         OriginalUses.push_back(InstructionAndIdx(UserI, U.getOperandNo()));
    2351             :       }
    2352             :       // Now, we can replace the uses.
    2353        2626 :       Inst->replaceAllUsesWith(New);
    2354        2626 :     }
    2355             : 
    2356             :     /// Reassign the original uses of Inst to Inst.
    2357        1105 :     void undo() override {
    2358             :       LLVM_DEBUG(dbgs() << "Undo: UsersReplacer: " << *Inst << "\n");
    2359        1434 :       for (use_iterator UseIt = OriginalUses.begin(),
    2360             :                         EndIt = OriginalUses.end();
    2361        2539 :            UseIt != EndIt; ++UseIt) {
    2362        1434 :         UseIt->Inst->setOperand(UseIt->Idx, Inst);
    2363             :       }
    2364        1105 :     }
    2365             :   };
    2366             : 
    2367             :   /// Remove an instruction from the IR.
    2368             :   class InstructionRemover : public TypePromotionAction {
    2369             :     /// Original position of the instruction.
    2370             :     InsertionHandler Inserter;
    2371             : 
    2372             :     /// Helper structure to hide all the link to the instruction. In other
    2373             :     /// words, this helps to do as if the instruction was removed.
    2374             :     OperandsHider Hider;
    2375             : 
    2376             :     /// Keep track of the uses replaced, if any.
    2377             :     UsesReplacer *Replacer = nullptr;
    2378             : 
    2379             :     /// Keep track of instructions removed.
    2380             :     SetOfInstrs &RemovedInsts;
    2381             : 
    2382             :   public:
    2383             :     /// Remove all reference of \p Inst and optionally replace all its
    2384             :     /// uses with New.
    2385             :     /// \p RemovedInsts Keep track of the instructions removed by this Action.
    2386             :     /// \pre If !Inst->use_empty(), then New != nullptr
    2387         495 :     InstructionRemover(Instruction *Inst, SetOfInstrs &RemovedInsts,
    2388             :                        Value *New = nullptr)
    2389         495 :         : TypePromotionAction(Inst), Inserter(Inst), Hider(Inst),
    2390         990 :           RemovedInsts(RemovedInsts) {
    2391         495 :       if (New)
    2392          37 :         Replacer = new UsesReplacer(Inst, New);
    2393             :       LLVM_DEBUG(dbgs() << "Do: InstructionRemover: " << *Inst << "\n");
    2394         495 :       RemovedInsts.insert(Inst);
    2395             :       /// The instructions removed here will be freed after completing
    2396             :       /// optimizeBlock() for all blocks as we need to keep track of the
    2397             :       /// removed instructions during promotion.
    2398         495 :       Inst->removeFromParent();
    2399         495 :     }
    2400             : 
    2401         990 :     ~InstructionRemover() override { delete Replacer; }
    2402             : 
    2403             :     /// Resurrect the instruction and reassign it to the proper uses if
    2404             :     /// new value was provided when build this action.
    2405         160 :     void undo() override {
    2406             :       LLVM_DEBUG(dbgs() << "Undo: InstructionRemover: " << *Inst << "\n");
    2407         160 :       Inserter.insert(Inst);
    2408         160 :       if (Replacer)
    2409          37 :         Replacer->undo();
    2410         160 :       Hider.undo();
    2411         160 :       RemovedInsts.erase(Inst);
    2412         160 :     }
    2413             :   };
    2414             : 
    2415             : public:
    2416             :   /// Restoration point.
    2417             :   /// The restoration point is a pointer to an action instead of an iterator
    2418             :   /// because the iterator may be invalidated but not the pointer.
    2419             :   using ConstRestorationPt = const TypePromotionAction *;
    2420             : 
    2421             :   TypePromotionTransaction(SetOfInstrs &RemovedInsts)
    2422     1758953 :       : RemovedInsts(RemovedInsts) {}
    2423             : 
    2424             :   /// Advocate every changes made in that transaction.
    2425             :   void commit();
    2426             : 
    2427             :   /// Undo all the changes made after the given point.
    2428             :   void rollback(ConstRestorationPt Point);
    2429             : 
    2430             :   /// Get the current restoration point.
    2431             :   ConstRestorationPt getRestorationPoint() const;
    2432             : 
    2433             :   /// \name API for IR modification with state keeping to support rollback.
    2434             :   /// @{
    2435             :   /// Same as Instruction::setOperand.
    2436             :   void setOperand(Instruction *Inst, unsigned Idx, Value *NewVal);
    2437             : 
    2438             :   /// Same as Instruction::eraseFromParent.
    2439             :   void eraseInstruction(Instruction *Inst, Value *NewVal = nullptr);
    2440             : 
    2441             :   /// Same as Value::replaceAllUsesWith.
    2442             :   void replaceAllUsesWith(Instruction *Inst, Value *New);
    2443             : 
    2444             :   /// Same as Value::mutateType.
    2445             :   void mutateType(Instruction *Inst, Type *NewTy);
    2446             : 
    2447             :   /// Same as IRBuilder::createTrunc.
    2448             :   Value *createTrunc(Instruction *Opnd, Type *Ty);
    2449             : 
    2450             :   /// Same as IRBuilder::createSExt.
    2451             :   Value *createSExt(Instruction *Inst, Value *Opnd, Type *Ty);
    2452             : 
    2453             :   /// Same as IRBuilder::createZExt.
    2454             :   Value *createZExt(Instruction *Inst, Value *Opnd, Type *Ty);
    2455             : 
    2456             :   /// Same as Instruction::moveBefore.
    2457             :   void moveBefore(Instruction *Inst, Instruction *Before);
    2458             :   /// @}
    2459             : 
    2460             : private:
    2461             :   /// The ordered list of actions made so far.
    2462             :   SmallVector<std::unique_ptr<TypePromotionAction>, 16> Actions;
    2463             : 
    2464             :   using CommitPt = SmallVectorImpl<std::unique_ptr<TypePromotionAction>>::iterator;
    2465             : 
    2466             :   SetOfInstrs &RemovedInsts;
    2467             : };
    2468             : 
    2469             : } // end anonymous namespace
    2470             : 
    2471        7083 : void TypePromotionTransaction::setOperand(Instruction *Inst, unsigned Idx,
    2472             :                                           Value *NewVal) {
    2473       14166 :   Actions.push_back(llvm::make_unique<TypePromotionTransaction::OperandSetter>(
    2474             :       Inst, Idx, NewVal));
    2475        7083 : }
    2476             : 
    2477         495 : void TypePromotionTransaction::eraseInstruction(Instruction *Inst,
    2478             :                                                 Value *NewVal) {
    2479         495 :   Actions.push_back(
    2480         495 :       llvm::make_unique<TypePromotionTransaction::InstructionRemover>(
    2481         495 :           Inst, RemovedInsts, NewVal));
    2482         495 : }
    2483             : 
    2484        2589 : void TypePromotionTransaction::replaceAllUsesWith(Instruction *Inst,
    2485             :                                                   Value *New) {
    2486        5178 :   Actions.push_back(
    2487             :       llvm::make_unique<TypePromotionTransaction::UsesReplacer>(Inst, New));
    2488        2589 : }
    2489             : 
    2490        2169 : void TypePromotionTransaction::mutateType(Instruction *Inst, Type *NewTy) {
    2491        2169 :   Actions.push_back(
    2492             :       llvm::make_unique<TypePromotionTransaction::TypeMutator>(Inst, NewTy));
    2493        2169 : }
    2494             : 
    2495         173 : Value *TypePromotionTransaction::createTrunc(Instruction *Opnd,
    2496             :                                              Type *Ty) {
    2497         173 :   std::unique_ptr<TruncBuilder> Ptr(new TruncBuilder(Opnd, Ty));
    2498         173 :   Value *Val = Ptr->getBuiltValue();
    2499         346 :   Actions.push_back(std::move(Ptr));
    2500         173 :   return Val;
    2501             : }
    2502             : 
    2503         103 : Value *TypePromotionTransaction::createSExt(Instruction *Inst,
    2504             :                                             Value *Opnd, Type *Ty) {
    2505         103 :   std::unique_ptr<SExtBuilder> Ptr(new SExtBuilder(Inst, Opnd, Ty));
    2506         103 :   Value *Val = Ptr->getBuiltValue();
    2507         206 :   Actions.push_back(std::move(Ptr));
    2508         103 :   return Val;
    2509             : }
    2510             : 
    2511         494 : Value *TypePromotionTransaction::createZExt(Instruction *Inst,
    2512             :                                             Value *Opnd, Type *Ty) {
    2513         494 :   std::unique_ptr<ZExtBuilder> Ptr(new ZExtBuilder(Inst, Opnd, Ty));
    2514         494 :   Value *Val = Ptr->getBuiltValue();
    2515         988 :   Actions.push_back(std::move(Ptr));
    2516         494 :   return Val;
    2517             : }
    2518             : 
    2519        2513 : void TypePromotionTransaction::moveBefore(Instruction *Inst,
    2520             :                                           Instruction *Before) {
    2521        5026 :   Actions.push_back(
    2522             :       llvm::make_unique<TypePromotionTransaction::InstructionMoveBefore>(
    2523             :           Inst, Before));
    2524        2513 : }
    2525             : 
    2526             : TypePromotionTransaction::ConstRestorationPt
    2527             : TypePromotionTransaction::getRestorationPoint() const {
    2528        2201 :   return !Actions.empty() ? Actions.back().get() : nullptr;
    2529             : }
    2530             : 
    2531             : void TypePromotionTransaction::commit() {
    2532             :   for (CommitPt It = Actions.begin(), EndIt = Actions.end(); It != EndIt;
    2533             :        ++It)
    2534             :     (*It)->commit();
    2535     1563877 :   Actions.clear();
    2536             : }
    2537             : 
    2538      223889 : void TypePromotionTransaction::rollback(
    2539             :     TypePromotionTransaction::ConstRestorationPt Point) {
    2540      237902 :   while (!Actions.empty() && Point != Actions.back().get()) {
    2541        6744 :     std::unique_ptr<TypePromotionAction> Curr = Actions.pop_back_val();
    2542        6744 :     Curr->undo();
    2543             :   }
    2544      223889 : }
    2545             : 
    2546             : namespace {
    2547             : 
    2548             : /// A helper class for matching addressing modes.
    2549             : ///
    2550             : /// This encapsulates the logic for matching the target-legal addressing modes.
    2551             : class AddressingModeMatcher {
    2552             :   SmallVectorImpl<Instruction*> &AddrModeInsts;
    2553             :   const TargetLowering &TLI;
    2554             :   const TargetRegisterInfo &TRI;
    2555             :   const DataLayout &DL;
    2556             : 
    2557             :   /// AccessTy/MemoryInst - This is the type for the access (e.g. double) and
    2558             :   /// the memory instruction that we're computing this address for.
    2559             :   Type *AccessTy;
    2560             :   unsigned AddrSpace;
    2561             :   Instruction *MemoryInst;
    2562             : 
    2563             :   /// This is the addressing mode that we're building up. This is
    2564             :   /// part of the return value of this addressing mode matching stuff.
    2565             :   ExtAddrMode &AddrMode;
    2566             : 
    2567             :   /// The instructions inserted by other CodeGenPrepare optimizations.
    2568             :   const SetOfInstrs &InsertedInsts;
    2569             : 
    2570             :   /// A map from the instructions to their type before promotion.
    2571             :   InstrToOrigTy &PromotedInsts;
    2572             : 
    2573             :   /// The ongoing transaction where every action should be registered.
    2574             :   TypePromotionTransaction &TPT;
    2575             : 
    2576             :   // A GEP which has too large offset to be folded into the addressing mode.
    2577             :   std::pair<AssertingVH<GetElementPtrInst>, int64_t> &LargeOffsetGEP;
    2578             : 
    2579             :   /// This is set to true when we should not do profitability checks.
    2580             :   /// When true, IsProfitableToFoldIntoAddressingMode always returns true.
    2581             :   bool IgnoreProfitability;
    2582             : 
    2583             :   AddressingModeMatcher(
    2584             :       SmallVectorImpl<Instruction *> &AMI, const TargetLowering &TLI,
    2585             :       const TargetRegisterInfo &TRI, Type *AT, unsigned AS, Instruction *MI,
    2586             :       ExtAddrMode &AM, const SetOfInstrs &InsertedInsts,
    2587             :       InstrToOrigTy &PromotedInsts, TypePromotionTransaction &TPT,
    2588             :       std::pair<AssertingVH<GetElementPtrInst>, int64_t> &LargeOffsetGEP)
    2589     1917698 :       : AddrModeInsts(AMI), TLI(TLI), TRI(TRI),
    2590     1917698 :         DL(MI->getModule()->getDataLayout()), AccessTy(AT), AddrSpace(AS),
    2591             :         MemoryInst(MI), AddrMode(AM), InsertedInsts(InsertedInsts),
    2592     3835396 :         PromotedInsts(PromotedInsts), TPT(TPT), LargeOffsetGEP(LargeOffsetGEP) {
    2593     1917698 :     IgnoreProfitability = false;
    2594             :   }
    2595             : 
    2596             : public:
    2597             :   /// Find the maximal addressing mode that a load/store of V can fold,
    2598             :   /// give an access type of AccessTy.  This returns a list of involved
    2599             :   /// instructions in AddrModeInsts.
    2600             :   /// \p InsertedInsts The instructions inserted by other CodeGenPrepare
    2601             :   /// optimizations.
    2602             :   /// \p PromotedInsts maps the instructions to their type before promotion.
    2603             :   /// \p The ongoing transaction where every action should be registered.
    2604             :   static ExtAddrMode
    2605     1917698 :   Match(Value *V, Type *AccessTy, unsigned AS, Instruction *MemoryInst,
    2606             :         SmallVectorImpl<Instruction *> &AddrModeInsts,
    2607             :         const TargetLowering &TLI, const TargetRegisterInfo &TRI,
    2608             :         const SetOfInstrs &InsertedInsts, InstrToOrigTy &PromotedInsts,
    2609             :         TypePromotionTransaction &TPT,
    2610             :         std::pair<AssertingVH<GetElementPtrInst>, int64_t> &LargeOffsetGEP) {
    2611     1917698 :     ExtAddrMode Result;
    2612             : 
    2613     1917698 :     bool Success = AddressingModeMatcher(AddrModeInsts, TLI, TRI, AccessTy, AS,
    2614             :                                          MemoryInst, Result, InsertedInsts,
    2615             :                                          PromotedInsts, TPT, LargeOffsetGEP)
    2616     1917698 :                        .matchAddr(V, 0);
    2617             :     (void)Success; assert(Success && "Couldn't select *anything*?");
    2618     1917698 :     return Result;
    2619             :   }
    2620             : 
    2621             : private:
    2622             :   bool matchScaledValue(Value *ScaleReg, int64_t Scale, unsigned Depth);
    2623             :   bool matchAddr(Value *Addr, unsigned Depth);
    2624             :   bool matchOperationAddr(User *AddrInst, unsigned Opcode, unsigned Depth,
    2625             :                           bool *MovedAway = nullptr);
    2626             :   bool isProfitableToFoldIntoAddressingMode(Instruction *I,
    2627             :                                             ExtAddrMode &AMBefore,
    2628             :                                             ExtAddrMode &AMAfter);
    2629             :   bool valueAlreadyLiveAtInst(Value *Val, Value *KnownLive1, Value *KnownLive2);
    2630             :   bool isPromotionProfitable(unsigned NewCost, unsigned OldCost,
    2631             :                              Value *PromotedOperand) const;
    2632             : };
    2633             : 
    2634             : /// Keep track of simplification of Phi nodes.
    2635             : /// Accept the set of all phi nodes and erase phi node from this set
    2636             : /// if it is simplified.
    2637             : class SimplificationTracker {
    2638             :   DenseMap<Value *, Value *> Storage;
    2639             :   const SimplifyQuery &SQ;
    2640             :   // Tracks newly created Phi nodes. We use a SetVector to get deterministic
    2641             :   // order when iterating over the set in MatchPhiSet.
    2642             :   SmallSetVector<PHINode *, 32> AllPhiNodes;
    2643             :   // Tracks newly created Select nodes.
    2644             :   SmallPtrSet<SelectInst *, 32> AllSelectNodes;
    2645             : 
    2646             : public:
    2647      148383 :   SimplificationTracker(const SimplifyQuery &sq)
    2648      148383 :       : SQ(sq) {}
    2649             : 
    2650             :   Value *Get(Value *V) {
    2651             :     do {
    2652      150019 :       auto SV = Storage.find(V);
    2653      150019 :       if (SV == Storage.end())
    2654      149351 :         return V;
    2655         594 :       V = SV->second;
    2656             :     } while (true);
    2657             :   }
    2658             : 
    2659      149315 :   Value *Simplify(Value *Val) {
    2660             :     SmallVector<Value *, 32> WorkList;
    2661             :     SmallPtrSet<Value *, 32> Visited;
    2662      149315 :     WorkList.push_back(Val);
    2663      298698 :     while (!WorkList.empty()) {
    2664             :       auto P = WorkList.pop_back_val();
    2665      149383 :       if (!Visited.insert(P).second)
    2666             :         continue;
    2667             :       if (auto *PI = dyn_cast<Instruction>(P))
    2668      149338 :         if (Value *V = SimplifyInstruction(cast<Instruction>(PI), SQ)) {
    2669         636 :           for (auto *U : PI->users())
    2670          68 :             WorkList.push_back(cast<Value>(U));
    2671             :           Put(PI, V);
    2672         568 :           PI->replaceAllUsesWith(V);
    2673         568 :           if (auto *PHI = dyn_cast<PHINode>(PI))
    2674         568 :             AllPhiNodes.remove(PHI);
    2675             :           if (auto *Select = dyn_cast<SelectInst>(PI))
    2676             :             AllSelectNodes.erase(Select);
    2677         568 :           PI->eraseFromParent();
    2678             :         }
    2679             :     }
    2680      149315 :     return Get(Val);
    2681             :   }
    2682             : 
    2683             :   void Put(Value *From, Value *To) {
    2684         568 :     Storage.insert({ From, To });
    2685             :   }
    2686             : 
    2687          36 :   void ReplacePhi(PHINode *From, PHINode *To) {
    2688          36 :     Value* OldReplacement = Get(From);
    2689          37 :     while (OldReplacement != From) {
    2690           1 :       From = To;
    2691             :       To = dyn_cast<PHINode>(OldReplacement);
    2692             :       OldReplacement = Get(From);
    2693             :     }
    2694             :     assert(Get(To) == To && "Replacement PHI node is already replaced.");
    2695             :     Put(From, To);
    2696          36 :     From->replaceAllUsesWith(To);
    2697          36 :     AllPhiNodes.remove(From);
    2698          36 :     From->eraseFromParent();
    2699          36 :   }
    2700             : 
    2701      148383 :   SmallSetVector<PHINode *, 32>& newPhiNodes() { return AllPhiNodes; }
    2702             : 
    2703      149286 :   void insertNewPhi(PHINode *PN) { AllPhiNodes.insert(PN); }
    2704             : 
    2705          29 :   void insertNewSelect(SelectInst *SI) { AllSelectNodes.insert(SI); }
    2706             : 
    2707             :   unsigned countNewPhiNodes() const { return AllPhiNodes.size(); }
    2708             : 
    2709           0 :   unsigned countNewSelectNodes() const { return AllSelectNodes.size(); }
    2710             : 
    2711      148310 :   void destroyNewNodes(Type *CommonType) {
    2712             :     // For safe erasing, replace the uses with dummy value first.
    2713      148310 :     auto Dummy = UndefValue::get(CommonType);
    2714      296967 :     for (auto I : AllPhiNodes) {
    2715      148657 :       I->replaceAllUsesWith(Dummy);
    2716      148657 :       I->eraseFromParent();
    2717             :     }
    2718             :     AllPhiNodes.clear();
    2719      148312 :     for (auto I : AllSelectNodes) {
    2720           2 :       I->replaceAllUsesWith(Dummy);
    2721           2 :       I->eraseFromParent();
    2722             :     }
    2723      148310 :     AllSelectNodes.clear();
    2724      148310 :   }
    2725             : };
    2726             : 
    2727             : /// A helper class for combining addressing modes.
    2728     1716614 : class AddressingModeCombiner {
    2729             :   typedef std::pair<Value *, BasicBlock *> ValueInBB;
    2730             :   typedef DenseMap<ValueInBB, Value *> FoldAddrToValueMapping;
    2731             :   typedef std::pair<PHINode *, PHINode *> PHIPair;
    2732             : 
    2733             : private:
    2734             :   /// The addressing modes we've collected.
    2735             :   SmallVector<ExtAddrMode, 16> AddrModes;
    2736             : 
    2737             :   /// The field in which the AddrModes differ, when we have more than one.
    2738             :   ExtAddrMode::FieldName DifferentField = ExtAddrMode::NoField;
    2739             : 
    2740             :   /// Are the AddrModes that we have all just equal to their original values?
    2741             :   bool AllAddrModesTrivial = true;
    2742             : 
    2743             :   /// Common Type for all different fields in addressing modes.
    2744             :   Type *CommonType;
    2745             : 
    2746             :   /// SimplifyQuery for simplifyInstruction utility.
    2747             :   const SimplifyQuery &SQ;
    2748             : 
    2749             :   /// Original Address.
    2750             :   ValueInBB Original;
    2751             : 
    2752             : public:
    2753             :   AddressingModeCombiner(const SimplifyQuery &_SQ, ValueInBB OriginalValue)
    2754     1716614 :       : CommonType(nullptr), SQ(_SQ), Original(OriginalValue) {}
    2755             : 
    2756             :   /// Get the combined AddrMode
    2757             :   const ExtAddrMode &getAddrMode() const {
    2758             :     return AddrModes[0];
    2759             :   }
    2760             : 
    2761             :   /// Add a new AddrMode if it's compatible with the AddrModes we already
    2762             :   /// have.
    2763             :   /// \return True iff we succeeded in doing so.
    2764     1917698 :   bool addNewAddrMode(ExtAddrMode &NewAddrMode) {
    2765             :     // Take note of if we have any non-trivial AddrModes, as we need to detect
    2766             :     // when all AddrModes are trivial as then we would introduce a phi or select
    2767             :     // which just duplicates what's already there.
    2768     1917698 :     AllAddrModesTrivial = AllAddrModesTrivial && NewAddrMode.isTrivial();
    2769             : 
    2770             :     // If this is the first addrmode then everything is fine.
    2771     1917698 :     if (AddrModes.empty()) {
    2772     1716614 :       AddrModes.emplace_back(NewAddrMode);
    2773     1716614 :       return true;
    2774             :     }
    2775             : 
    2776             :     // Figure out how different this is from the other address modes, which we
    2777             :     // can do just by comparing against the first one given that we only care
    2778             :     // about the cumulative difference.
    2779             :     ExtAddrMode::FieldName ThisDifferentField =
    2780      201084 :       AddrModes[0].compare(NewAddrMode);
    2781      201084 :     if (DifferentField == ExtAddrMode::NoField)
    2782      154823 :       DifferentField = ThisDifferentField;
    2783       46261 :     else if (DifferentField != ThisDifferentField)
    2784         256 :       DifferentField = ExtAddrMode::MultipleFields;
    2785             : 
    2786             :     // If NewAddrMode differs in more than one dimension we cannot handle it.
    2787      201084 :     bool CanHandle = DifferentField != ExtAddrMode::MultipleFields;
    2788             : 
    2789             :     // If Scale Field is different then we reject.
    2790      201084 :     CanHandle = CanHandle && DifferentField != ExtAddrMode::ScaleField;
    2791             : 
    2792             :     // We also must reject the case when base offset is different and
    2793             :     // scale reg is not null, we cannot handle this case due to merge of
    2794             :     // different offsets will be used as ScaleReg.
    2795      196412 :     CanHandle = CanHandle && (DifferentField != ExtAddrMode::BaseOffsField ||
    2796      193741 :                               !NewAddrMode.ScaledReg);
    2797             : 
    2798             :     // We also must reject the case when GV is different and BaseReg installed
    2799             :     // due to we want to use base reg as a merge of GV values.
    2800      196411 :     CanHandle = CanHandle && (DifferentField != ExtAddrMode::BaseGVField ||
    2801         139 :                               !NewAddrMode.HasBaseReg);
    2802             : 
    2803             :     // Even if NewAddMode is the same we still need to collect it due to
    2804             :     // original value is different. And later we will need all original values
    2805             :     // as anchors during finding the common Phi node.
    2806             :     if (CanHandle)
    2807      196410 :       AddrModes.emplace_back(NewAddrMode);
    2808             :     else
    2809             :       AddrModes.clear();
    2810             : 
    2811             :     return CanHandle;
    2812             :   }
    2813             : 
    2814             :   /// Combine the addressing modes we've collected into a single
    2815             :   /// addressing mode.
    2816             :   /// \return True iff we successfully combined them or we only had one so
    2817             :   /// didn't need to combine them anyway.
    2818     1716614 :   bool combineAddrModes() {
    2819             :     // If we have no AddrModes then they can't be combined.
    2820     3433228 :     if (AddrModes.size() == 0)
    2821             :       return false;
    2822             : 
    2823             :     // A single AddrMode can trivially be combined.
    2824     1711940 :     if (AddrModes.size() == 1 || DifferentField == ExtAddrMode::NoField)
    2825             :       return true;
    2826             : 
    2827             :     // If the AddrModes we collected are all just equal to the value they are
    2828             :     // derived from then combining them wouldn't do anything useful.
    2829      149603 :     if (AllAddrModesTrivial)
    2830             :       return false;
    2831             : 
    2832      148387 :     if (!addrModeCombiningAllowed())
    2833             :       return false;
    2834             : 
    2835             :     // Build a map between <original value, basic block where we saw it> to
    2836             :     // value of base register.
    2837             :     // Bail out if there is no common type.
    2838             :     FoldAddrToValueMapping Map;
    2839      148387 :     if (!initializeMap(Map))
    2840             :       return false;
    2841             : 
    2842      148383 :     Value *CommonValue = findCommon(Map);
    2843      148383 :     if (CommonValue)
    2844          73 :       AddrModes[0].SetCombinedField(DifferentField, CommonValue, AddrModes);
    2845      148383 :     return CommonValue != nullptr;
    2846             :   }
    2847             : 
    2848             : private:
    2849             :   /// Initialize Map with anchor values. For address seen in some BB
    2850             :   /// we set the value of different field saw in this address.
    2851             :   /// If address is not an instruction than basic block is set to null.
    2852             :   /// At the same time we find a common type for different field we will
    2853             :   /// use to create new Phi/Select nodes. Keep it in CommonType field.
    2854             :   /// Return false if there is no common type found.
    2855      148387 :   bool initializeMap(FoldAddrToValueMapping &Map) {
    2856             :     // Keep track of keys where the value is null. We will need to replace it
    2857             :     // with constant null when we know the common type.
    2858             :     SmallVector<ValueInBB, 2> NullValue;
    2859      296774 :     Type *IntPtrTy = SQ.DL.getIntPtrType(AddrModes[0].OriginalValue->getType());
    2860      490870 :     for (auto &AM : AddrModes) {
    2861             :       BasicBlock *BB = nullptr;
    2862      342487 :       if (Instruction *I = dyn_cast<Instruction>(AM.OriginalValue))
    2863         696 :         BB = I->getParent();
    2864             : 
    2865      342487 :       Value *DV = AM.GetFieldAsValue(DifferentField, IntPtrTy);
    2866      342487 :       if (DV) {
    2867      342443 :         auto *Type = DV->getType();
    2868      342443 :         if (CommonType && CommonType != Type)
    2869             :           return false;
    2870      342439 :         CommonType = Type;
    2871      342439 :         Map[{ AM.OriginalValue, BB }] = DV;
    2872             :       } else {
    2873          44 :         NullValue.push_back({ AM.OriginalValue, BB });
    2874             :       }
    2875             :     }
    2876             :     assert(CommonType && "At least one non-null value must be!");
    2877      148423 :     for (auto VIBB : NullValue)
    2878          40 :       Map[VIBB] = Constant::getNullValue(CommonType);
    2879      148383 :     return true;
    2880             :   }
    2881             : 
    2882             :   /// We have mapping between value A and basic block where value A
    2883             :   /// seen to other value B where B was a field in addressing mode represented
    2884             :   /// by A. Also we have an original value C representing an address in some
    2885             :   /// basic block. Traversing from C through phi and selects we ended up with
    2886             :   /// A's in a map. This utility function tries to find a value V which is a
    2887             :   /// field in addressing mode C and traversing through phi nodes and selects
    2888             :   /// we will end up in corresponded values B in a map.
    2889             :   /// The utility will create a new Phi/Selects if needed.
    2890             :   // The simple example looks as follows:
    2891             :   // BB1:
    2892             :   //   p1 = b1 + 40
    2893             :   //   br cond BB2, BB3
    2894             :   // BB2:
    2895             :   //   p2 = b2 + 40
    2896             :   //   br BB3
    2897             :   // BB3:
    2898             :   //   p = phi [p1, BB1], [p2, BB2]
    2899             :   //   v = load p
    2900             :   // Map is
    2901             :   //   <p1, BB1> -> b1
    2902             :   //   <p2, BB2> -> b2
    2903             :   // Request is
    2904             :   //   <p, BB3> -> ?
    2905             :   // The function tries to find or build phi [b1, BB1], [b2, BB2] in BB3
    2906      148383 :   Value *findCommon(FoldAddrToValueMapping &Map) {
    2907             :     // Tracks the simplification of newly created phi nodes. The reason we use
    2908             :     // this mapping is because we will add new created Phi nodes in AddrToBase.
    2909             :     // Simplification of Phi nodes is recursive, so some Phi node may
    2910             :     // be simplified after we added it to AddrToBase.
    2911             :     // Using this mapping we can find the current value in AddrToBase.
    2912      296766 :     SimplificationTracker ST(SQ);
    2913             : 
    2914             :     // First step, DFS to create PHI nodes for all intermediate blocks.
    2915             :     // Also fill traverse order for the second step.
    2916             :     SmallVector<ValueInBB, 32> TraverseOrder;
    2917      148383 :     InsertPlaceholders(Map, TraverseOrder, ST);
    2918             : 
    2919             :     // Second Step, fill new nodes by merged values and simplify if possible.
    2920      148383 :     FillPlaceholders(Map, TraverseOrder, ST);
    2921             : 
    2922      148383 :     if (!AddrSinkNewSelects && ST.countNewSelectNodes() > 0) {
    2923           0 :       ST.destroyNewNodes(CommonType);
    2924           0 :       return nullptr;
    2925             :     }
    2926             : 
    2927             :     // Now we'd like to match New Phi nodes to existed ones.
    2928      148383 :     unsigned PhiNotMatchedCount = 0;
    2929      148383 :     if (!MatchPhiSet(ST, AddrSinkNewPhis, PhiNotMatchedCount)) {
    2930      148310 :       ST.destroyNewNodes(CommonType);
    2931      148310 :       return nullptr;
    2932             :     }
    2933             : 
    2934         146 :     auto *Result = ST.Get(Map.find(Original)->second);
    2935             :     if (Result) {
    2936             :       NumMemoryInstsPhiCreated += ST.countNewPhiNodes() + PhiNotMatchedCount;
    2937             :       NumMemoryInstsSelectCreated += ST.countNewSelectNodes();
    2938             :     }
    2939             :     return Result;
    2940             :   }
    2941             : 
    2942             :   /// Try to match PHI node to Candidate.
    2943             :   /// Matcher tracks the matched Phi nodes.
    2944           0 :   bool MatchPhiNode(PHINode *PHI, PHINode *Candidate,
    2945             :                     SmallSetVector<PHIPair, 8> &Matcher,
    2946             :                     SmallSetVector<PHINode *, 32> &PhiNodesToMatch) {
    2947             :     SmallVector<PHIPair, 8> WorkList;
    2948           0 :     Matcher.insert({ PHI, Candidate });
    2949           0 :     WorkList.push_back({ PHI, Candidate });
    2950           0 :     SmallSet<PHIPair, 8> Visited;
    2951           0 :     while (!WorkList.empty()) {
    2952           0 :       auto Item = WorkList.pop_back_val();
    2953           0 :       if (!Visited.insert(Item).second)
    2954           0 :         continue;
    2955             :       // We iterate over all incoming values to Phi to compare them.
    2956             :       // If values are different and both of them Phi and the first one is a
    2957             :       // Phi we added (subject to match) and both of them is in the same basic
    2958             :       // block then we can match our pair if values match. So we state that
    2959             :       // these values match and add it to work list to verify that.
    2960           0 :       for (auto B : Item.first->blocks()) {
    2961           0 :         Value *FirstValue = Item.first->getIncomingValueForBlock(B);
    2962           0 :         Value *SecondValue = Item.second->getIncomingValueForBlock(B);
    2963           0 :         if (FirstValue == SecondValue)
    2964           0 :           continue;
    2965             : 
    2966             :         PHINode *FirstPhi = dyn_cast<PHINode>(FirstValue);
    2967             :         PHINode *SecondPhi = dyn_cast<PHINode>(SecondValue);
    2968             : 
    2969             :         // One of them is not Phi or
    2970             :         // The first one is not Phi node from the set we'd like to match or
    2971             :         // Phi nodes from different basic blocks then
    2972             :         // we will not be able to match.
    2973           0 :         if (!FirstPhi || !SecondPhi || !PhiNodesToMatch.count(FirstPhi) ||
    2974           0 :             FirstPhi->getParent() != SecondPhi->getParent())
    2975           0 :           return false;
    2976             : 
    2977             :         // If we already matched them then continue.
    2978           0 :         if (Matcher.count({ FirstPhi, SecondPhi }))
    2979           0 :           continue;
    2980             :         // So the values are different and does not match. So we need them to
    2981             :         // match.
    2982           0 :         Matcher.insert({ FirstPhi, SecondPhi });
    2983             :         // But me must check it.
    2984           0 :         WorkList.push_back({ FirstPhi, SecondPhi });
    2985             :       }
    2986             :     }
    2987             :     return true;
    2988             :   }
    2989             : 
    2990             :   /// For the given set of PHI nodes (in the SimplificationTracker) try
    2991             :   /// to find their equivalents.
    2992             :   /// Returns false if this matching fails and creation of new Phi is disabled.
    2993      148383 :   bool MatchPhiSet(SimplificationTracker &ST, bool AllowNewPhiNodes,
    2994             :                    unsigned &PhiNotMatchedCount) {
    2995             :     // Use a SetVector for Matched to make sure we do replacements (ReplacePhi)
    2996             :     // in a deterministic order below.
    2997             :     SmallSetVector<PHIPair, 8> Matched;
    2998             :     SmallPtrSet<PHINode *, 8> WillNotMatch;
    2999             :     SmallSetVector<PHINode *, 32> &PhiNodesToMatch = ST.newPhiNodes();
    3000      148438 :     while (PhiNodesToMatch.size()) {
    3001      148365 :       PHINode *PHI = *PhiNodesToMatch.begin();
    3002             : 
    3003             :       // Add us, if no Phi nodes in the basic block we do not match.
    3004      148365 :       WillNotMatch.clear();
    3005      148365 :       WillNotMatch.insert(PHI);
    3006             : 
    3007             :       // Traverse all Phis until we found equivalent or fail to do that.
    3008             :       bool IsMatched = false;
    3009      716228 :       for (auto &P : PHI->getParent()->phis()) {
    3010      419530 :         if (&P == PHI)
    3011             :           continue;
    3012      271165 :         if ((IsMatched = MatchPhiNode(PHI, &P, Matched, PhiNodesToMatch)))
    3013             :           break;
    3014             :         // If it does not match, collect all Phi nodes from matcher.
    3015             :         // if we end up with no match, them all these Phi nodes will not match
    3016             :         // later.
    3017      542596 :         for (auto M : Matched)
    3018      271463 :           WillNotMatch.insert(M.first);
    3019             :         Matched.clear();
    3020             :       }
    3021      148365 :       if (IsMatched) {
    3022             :         // Replace all matched values and erase them.
    3023          68 :         for (auto MV : Matched)
    3024          36 :           ST.ReplacePhi(MV.first, MV.second);
    3025             :         Matched.clear();
    3026          32 :         continue;
    3027             :       }
    3028             :       // If we are not allowed to create new nodes then bail out.
    3029      148333 :       if (!AllowNewPhiNodes)
    3030             :         return false;
    3031             :       // Just remove all seen values in matcher. They will not match anything.
    3032          23 :       PhiNotMatchedCount += WillNotMatch.size();
    3033          49 :       for (auto *P : WillNotMatch)
    3034          26 :         PhiNodesToMatch.remove(P);
    3035             :     }
    3036             :     return true;
    3037             :   }
    3038             :   /// Fill the placeholder with values from predecessors and simplify it.
    3039           0 :   void FillPlaceholders(FoldAddrToValueMapping &Map,
    3040             :                         SmallVectorImpl<ValueInBB> &TraverseOrder,
    3041             :                         SimplificationTracker &ST) {
    3042           0 :     while (!TraverseOrder.empty()) {
    3043           0 :       auto Current = TraverseOrder.pop_back_val();
    3044             :       assert(Map.find(Current) != Map.end() && "No node to fill!!!");
    3045             :       Value *CurrentValue = Current.first;
    3046             :       BasicBlock *CurrentBlock = Current.second;
    3047           0 :       Value *V = Map[Current];
    3048             : 
    3049             :       if (SelectInst *Select = dyn_cast<SelectInst>(V)) {
    3050             :         // CurrentValue also must be Select.
    3051             :         auto *CurrentSelect = cast<SelectInst>(CurrentValue);
    3052             :         auto *TrueValue = CurrentSelect->getTrueValue();
    3053             :         ValueInBB TrueItem = { TrueValue, isa<Instruction>(TrueValue)
    3054           0 :                                               ? CurrentBlock
    3055             :                                               : nullptr };
    3056             :         assert(Map.find(TrueItem) != Map.end() && "No True Value!");
    3057           0 :         Select->setTrueValue(ST.Get(Map[TrueItem]));
    3058             :         auto *FalseValue = CurrentSelect->getFalseValue();
    3059             :         ValueInBB FalseItem = { FalseValue, isa<Instruction>(FalseValue)
    3060           0 :                                                 ? CurrentBlock
    3061             :                                                 : nullptr };
    3062             :         assert(Map.find(FalseItem) != Map.end() && "No False Value!");
    3063           0 :         Select->setFalseValue(ST.Get(Map[FalseItem]));
    3064             :       } else {
    3065             :         // Must be a Phi node then.
    3066             :         PHINode *PHI = cast<PHINode>(V);
    3067             :         // Fill the Phi node with values from predecessors.
    3068             :         bool IsDefinedInThisBB =
    3069           0 :             cast<Instruction>(CurrentValue)->getParent() == CurrentBlock;
    3070             :         auto *CurrentPhi = dyn_cast<PHINode>(CurrentValue);
    3071           0 :         for (auto B : predecessors(CurrentBlock)) {
    3072             :           Value *PV = IsDefinedInThisBB
    3073           0 :                           ? CurrentPhi->getIncomingValueForBlock(B)
    3074             :                           : CurrentValue;
    3075           0 :           ValueInBB item = { PV, isa<Instruction>(PV) ? B : nullptr };
    3076             :           assert(Map.find(item) != Map.end() && "No predecessor Value!");
    3077           0 :           PHI->addIncoming(ST.Get(Map[item]), B);
    3078             :         }
    3079             :       }
    3080             :       // Simplify if possible.
    3081           0 :       Map[Current] = ST.Simplify(V);
    3082             :     }
    3083           0 :   }
    3084             : 
    3085             :   /// Starting from value recursively iterates over predecessors up to known
    3086             :   /// ending values represented in a map. For each traversed block inserts
    3087             :   /// a placeholder Phi or Select.
    3088             :   /// Reports all new created Phi/Select nodes by adding them to set.
    3089             :   /// Also reports and order in what basic blocks have been traversed.
    3090      148383 :   void InsertPlaceholders(FoldAddrToValueMapping &Map,
    3091             :                           SmallVectorImpl<ValueInBB> &TraverseOrder,
    3092             :                           SimplificationTracker &ST) {
    3093             :     SmallVector<ValueInBB, 32> Worklist;
    3094             :     assert((isa<PHINode>(Original.first) || isa<SelectInst>(Original.first)) &&
    3095             :            "Address must be a Phi or Select node");
    3096      148383 :     auto *Dummy = UndefValue::get(CommonType);
    3097      148383 :     Worklist.push_back(Original);
    3098      642765 :     while (!Worklist.empty()) {
    3099      494382 :       auto Current = Worklist.pop_back_val();
    3100             :       // If value is not an instruction it is something global, constant,
    3101             :       // parameter and we can say that this value is observable in any block.
    3102             :       // Set block to null to denote it.
    3103             :       // Also please take into account that it is how we build anchors.
    3104      494382 :       if (!isa<Instruction>(Current.first))
    3105      344207 :         Current.second = nullptr;
    3106             :       // if it is already visited or it is an ending value then skip it.
    3107      494382 :       if (Map.find(Current) != Map.end())
    3108      345635 :         continue;
    3109      149315 :       TraverseOrder.push_back(Current);
    3110             : 
    3111      149315 :       Value *CurrentValue = Current.first;
    3112      149315 :       BasicBlock *CurrentBlock = Current.second;
    3113             :       // CurrentValue must be a Phi node or select. All others must be covered
    3114             :       // by anchors.
    3115             :       Instruction *CurrentI = cast<Instruction>(CurrentValue);
    3116      149315 :       bool IsDefinedInThisBB = CurrentI->getParent() == CurrentBlock;
    3117             : 
    3118      149315 :       unsigned PredCount = pred_size(CurrentBlock);
    3119             :       // if Current Value is not defined in this basic block we are interested
    3120             :       // in values in predecessors.
    3121      149315 :       if (!IsDefinedInThisBB) {
    3122             :         assert(PredCount && "Unreachable block?!");
    3123        1136 :         PHINode *PHI = PHINode::Create(CommonType, PredCount, "sunk_phi",
    3124             :                                        &CurrentBlock->front());
    3125         568 :         Map[Current] = PHI;
    3126         568 :         ST.insertNewPhi(PHI);
    3127             :         // Add all predecessors in work list.
    3128        1289 :         for (auto B : predecessors(CurrentBlock))
    3129         721 :           Worklist.push_back({ CurrentValue, B });
    3130         568 :         continue;
    3131             :       }
    3132             :       // Value is defined in this basic block.
    3133             :       if (SelectInst *OrigSelect = dyn_cast<SelectInst>(CurrentI)) {
    3134             :         // Is it OK to get metadata from OrigSelect?!
    3135             :         // Create a Select placeholder with dummy value.
    3136             :         SelectInst *Select =
    3137          29 :             SelectInst::Create(OrigSelect->getCondition(), Dummy, Dummy,
    3138          58 :                                OrigSelect->getName(), OrigSelect, OrigSelect);
    3139          29 :         Map[Current] = Select;
    3140             :         ST.insertNewSelect(Select);
    3141             :         // We are interested in True and False value in this basic block.
    3142          29 :         Worklist.push_back({ OrigSelect->getTrueValue(), CurrentBlock });
    3143          29 :         Worklist.push_back({ OrigSelect->getFalseValue(), CurrentBlock });
    3144             :       } else {
    3145             :         // It must be a Phi node then.
    3146             :         auto *CurrentPhi = cast<PHINode>(CurrentI);
    3147             :         // Create new Phi node for merge of bases.
    3148             :         assert(PredCount && "Unreachable block?!");
    3149      297436 :         PHINode *PHI = PHINode::Create(CommonType, PredCount, "sunk_phi",
    3150             :                                        &CurrentBlock->front());
    3151      148718 :         Map[Current] = PHI;
    3152      148718 :         ST.insertNewPhi(PHI);
    3153             : 
    3154             :         // Add all predecessors in work list.
    3155      493938 :         for (auto B : predecessors(CurrentBlock))
    3156      690440 :           Worklist.push_back({ CurrentPhi->getIncomingValueForBlock(B), B });
    3157             :       }
    3158             :     }
    3159      148383 :   }
    3160             : 
    3161           0 :   bool addrModeCombiningAllowed() {
    3162           0 :     if (DisableComplexAddrModes)
    3163           0 :       return false;
    3164           0 :     switch (DifferentField) {
    3165             :     default:
    3166             :       return false;
    3167             :     case ExtAddrMode::BaseRegField:
    3168           0 :       return AddrSinkCombineBaseReg;
    3169             :     case ExtAddrMode::BaseGVField:
    3170           0 :       return AddrSinkCombineBaseGV;
    3171             :     case ExtAddrMode::BaseOffsField:
    3172           0 :       return AddrSinkCombineBaseOffs;
    3173             :     case ExtAddrMode::ScaledRegField:
    3174           0 :       return AddrSinkCombineScaledReg;
    3175             :     }
    3176             :   }
    3177             : };
    3178             : } // end anonymous namespace
    3179             : 
    3180             : /// Try adding ScaleReg*Scale to the current addressing mode.
    3181             : /// Return true and update AddrMode if this addr mode is legal for the target,
    3182             : /// false if not.
    3183       68638 : bool AddressingModeMatcher::matchScaledValue(Value *ScaleReg, int64_t Scale,
    3184             :                                              unsigned Depth) {
    3185             :   // If Scale is 1, then this is the same as adding ScaleReg to the addressing
    3186             :   // mode.  Just process that directly.
    3187       68638 :   if (Scale == 1)
    3188       23020 :     return matchAddr(ScaleReg, Depth);
    3189             : 
    3190             :   // If the scale is 0, it takes nothing to add this.
    3191       45618 :   if (Scale == 0)
    3192             :     return true;
    3193             : 
    3194             :   // If we already have a scale of this value, we can add to it, otherwise, we
    3195             :   // need an available scale field.
    3196       45614 :   if (AddrMode.Scale != 0 && AddrMode.ScaledReg != ScaleReg)
    3197             :     return false;
    3198             : 
    3199       44931 :   ExtAddrMode TestAddrMode = AddrMode;
    3200             : 
    3201             :   // Add scale to turn X*4+X*3 -> X*7.  This could also do things like
    3202             :   // [A+B + A*7] -> [B+A*8].
    3203       44931 :   TestAddrMode.Scale += Scale;
    3204       44931 :   TestAddrMode.ScaledReg = ScaleReg;
    3205             : 
    3206             :   // If the new address isn't legal, bail out.
    3207       44931 :   if (!TLI.isLegalAddressingMode(DL, TestAddrMode, AccessTy, AddrSpace))
    3208             :     return false;
    3209             : 
    3210             :   // It was legal, so commit it.
    3211       12900 :   AddrMode = TestAddrMode;
    3212             : 
    3213             :   // Okay, we decided that we can add ScaleReg+Scale to AddrMode.  Check now
    3214             :   // to see if ScaleReg is actually X+C.  If so, we can turn this into adding
    3215             :   // X*Scale + C*Scale to addr mode.
    3216       12900 :   ConstantInt *CI = nullptr; Value *AddLHS = nullptr;
    3217       25021 :   if (isa<Instruction>(ScaleReg) &&  // not a constant expr.
    3218       22991 :       match(ScaleReg, m_Add(m_Value(AddLHS), m_ConstantInt(CI)))) {
    3219        2030 :     TestAddrMode.ScaledReg = AddLHS;
    3220        2030 :     TestAddrMode.BaseOffs += CI->getSExtValue()*TestAddrMode.Scale;
    3221             : 
    3222             :     // If this addressing mode is legal, commit it and remember that we folded
    3223             :     // this instruction.
    3224        2030 :     if (TLI.isLegalAddressingMode(DL, TestAddrMode, AccessTy, AddrSpace)) {
    3225        1937 :       AddrModeInsts.push_back(cast<Instruction>(ScaleReg));
    3226        1937 :       AddrMode = TestAddrMode;
    3227        1937 :       return true;
    3228             :     }
    3229             :   }
    3230             : 
    3231             :   // Otherwise, not (x+c)*scale, just return what we have.
    3232             :   return true;
    3233             : }
    3234             : 
    3235             : /// This is a little filter, which returns true if an addressing computation
    3236             : /// involving I might be folded into a load/store accessing it.
    3237             : /// This doesn't need to be perfect, but needs to accept at least
    3238             : /// the set of instructions that MatchOperationAddr can.
    3239       45775 : static bool MightBeFoldableInst(Instruction *I) {
    3240             :   switch (I->getOpcode()) {
    3241       17012 :   case Instruction::BitCast:
    3242             :   case Instruction::AddrSpaceCast:
    3243             :     // Don't touch identity bitcasts.
    3244       34024 :     if (I->getType() == I->getOperand(0)->getType())
    3245             :       return false;
    3246             :     return I->getType()->isIntOrPtrTy();
    3247             :   case Instruction::PtrToInt:
    3248             :     // PtrToInt is always a noop, as we know that the int type is pointer sized.
    3249             :     return true;
    3250             :   case Instruction::IntToPtr:
    3251             :     // We know the input is intptr_t, so this is foldable.
    3252             :     return true;
    3253             :   case Instruction::Add:
    3254             :     return true;
    3255          30 :   case Instruction::Mul:
    3256             :   case Instruction::Shl:
    3257             :     // Can only handle X*C and X << C.
    3258          30 :     return isa<ConstantInt>(I->getOperand(1));
    3259             :   case Instruction::GetElementPtr:
    3260             :     return true;
    3261             :   default:
    3262             :     return false;
    3263             :   }
    3264             : }
    3265             : 
    3266             : /// Check whether or not \p Val is a legal instruction for \p TLI.
    3267             : /// \note \p Val is assumed to be the product of some type promotion.
    3268             : /// Therefore if \p Val has an undefined state in \p TLI, this is assumed
    3269             : /// to be legal, as the non-promoted value would have had the same state.
    3270        2219 : static bool isPromotedInstructionLegal(const TargetLowering &TLI,
    3271             :                                        const DataLayout &DL, Value *Val) {
    3272             :   Instruction *PromotedInst = dyn_cast<Instruction>(Val);
    3273             :   if (!PromotedInst)
    3274             :     return false;
    3275        4436 :   int ISDOpcode = TLI.InstructionOpcodeToISD(PromotedInst->getOpcode());
    3276             :   // If the ISDOpcode is undefined, it was undefined before the promotion.
    3277        2218 :   if (!ISDOpcode)
    3278             :     return true;
    3279             :   // Otherwise, check if the promoted instruction is legal or not.
    3280        2218 :   return TLI.isOperationLegalOrCustom(
    3281        2218 :       ISDOpcode, TLI.getValueType(DL, PromotedInst->getType()));
    3282             : }
    3283             : 
    3284             : namespace {
    3285             : 
    3286             : /// Hepler class to perform type promotion.
    3287             : class TypePromotionHelper {
    3288             :   /// Utility function to add a promoted instruction \p ExtOpnd to
    3289             :   /// \p PromotedInsts and record the type of extension we have seen.
    3290        2169 :   static void addPromotedInst(InstrToOrigTy &PromotedInsts,
    3291             :                               Instruction *ExtOpnd,
    3292             :                               bool IsSExt) {
    3293        2169 :     ExtType ExtTy = IsSExt ? SignExtension : ZeroExtension;
    3294        2169 :     InstrToOrigTy::iterator It = PromotedInsts.find(ExtOpnd);
    3295        2169 :     if (It != PromotedInsts.end()) {
    3296             :       // If the new extension is same as original, the information in
    3297             :       // PromotedInsts[ExtOpnd] is still correct.
    3298        1008 :       if (It->second.getInt() == ExtTy)
    3299         503 :         return;
    3300             : 
    3301             :       // Now the new extension is different from old extension, we make
    3302             :       // the type information invalid by setting extension type to
    3303             :       // BothExtension.
    3304             :       ExtTy = BothExtension;
    3305             :     }
    3306        1666 :     PromotedInsts[ExtOpnd] = TypeIsSExt(ExtOpnd->getType(), ExtTy);
    3307             :   }
    3308             : 
    3309             :   /// Utility function to query the original type of instruction \p Opnd
    3310             :   /// with a matched extension type. If the extension doesn't match, we
    3311             :   /// cannot use the information we had on the original type.
    3312             :   /// BothExtension doesn't match any extension type.
    3313         965 :   static const Type *getOrigType(const InstrToOrigTy &PromotedInsts,
    3314             :                                  Instruction *Opnd,
    3315             :                                  bool IsSExt) {
    3316         965 :     ExtType ExtTy = IsSExt ? SignExtension : ZeroExtension;
    3317         965 :     InstrToOrigTy::const_iterator It = PromotedInsts.find(Opnd);
    3318         965 :     if (It != PromotedInsts.end() && It->second.getInt() == ExtTy)
    3319          45 :       return It->second.getPointer();
    3320             :     return nullptr;
    3321             :   }
    3322             : 
    3323             :   /// Utility function to check whether or not a sign or zero extension
    3324             :   /// of \p Inst with \p ConsideredExtType can be moved through \p Inst by
    3325             :   /// either using the operands of \p Inst or promoting \p Inst.
    3326             :   /// The type of the extension is defined by \p IsSExt.
    3327             :   /// In other words, check if:
    3328             :   /// ext (Ty Inst opnd1 opnd2 ... opndN) to ConsideredExtType.
    3329             :   /// #1 Promotion applies:
    3330             :   /// ConsideredExtType Inst (ext opnd1 to ConsideredExtType, ...).
    3331             :   /// #2 Operand reuses:
    3332             :   /// ext opnd1 to ConsideredExtType.
    3333             :   /// \p PromotedInsts maps the instructions to their type before promotion.
    3334             :   static bool canGetThrough(const Instruction *Inst, Type *ConsideredExtType,
    3335             :                             const InstrToOrigTy &PromotedInsts, bool IsSExt);
    3336             : 
    3337             :   /// Utility function to determine if \p OpIdx should be promoted when
    3338             :   /// promoting \p Inst.
    3339             :   static bool shouldExtOperand(const Instruction *Inst, int OpIdx) {
    3340        4338 :     return !(isa<SelectInst>(Inst) && OpIdx == 0);
    3341             :   }
    3342             : 
    3343             :   /// Utility function to promote the operand of \p Ext when this
    3344             :   /// operand is a promotable trunc or sext or zext.
    3345             :   /// \p PromotedInsts maps the instructions to their type before promotion.
    3346             :   /// \p CreatedInstsCost[out] contains the cost of all instructions
    3347             :   /// created to promote the operand of Ext.
    3348             :   /// Newly added extensions are inserted in \p Exts.
    3349             :   /// Newly added truncates are inserted in \p Truncs.
    3350             :   /// Should never be called directly.
    3351             :   /// \return The promoted value which is used instead of Ext.
    3352             :   static Value *promoteOperandForTruncAndAnyExt(
    3353             :       Instruction *Ext, TypePromotionTransaction &TPT,
    3354             :       InstrToOrigTy &PromotedInsts, unsigned &CreatedInstsCost,
    3355             :       SmallVectorImpl<Instruction *> *Exts,
    3356             :       SmallVectorImpl<Instruction *> *Truncs, const TargetLowering &TLI);
    3357             : 
    3358             :   /// Utility function to promote the operand of \p Ext when this
    3359             :   /// operand is promotable and is not a supported trunc or sext.
    3360             :   /// \p PromotedInsts maps the instructions to their type before promotion.
    3361             :   /// \p CreatedInstsCost[out] contains the cost of all the instructions
    3362             :   /// created to promote the operand of Ext.
    3363             :   /// Newly added extensions are inserted in \p Exts.
    3364             :   /// Newly added truncates are inserted in \p Truncs.
    3365             :   /// Should never be called directly.
    3366             :   /// \return The promoted value which is used instead of Ext.
    3367             :   static Value *promoteOperandForOther(Instruction *Ext,
    3368             :                                        TypePromotionTransaction &TPT,
    3369             :                                        InstrToOrigTy &PromotedInsts,
    3370             :                                        unsigned &CreatedInstsCost,
    3371             :                                        SmallVectorImpl<Instruction *> *Exts,
    3372             :                                        SmallVectorImpl<Instruction *> *Truncs,
    3373             :                                        const TargetLowering &TLI, bool IsSExt);
    3374             : 
    3375             :   /// \see promoteOperandForOther.
    3376         390 :   static Value *signExtendOperandForOther(
    3377             :       Instruction *Ext, TypePromotionTransaction &TPT,
    3378             :       InstrToOrigTy &PromotedInsts, unsigned &CreatedInstsCost,
    3379             :       SmallVectorImpl<Instruction *> *Exts,
    3380             :       SmallVectorImpl<Instruction *> *Truncs, const TargetLowering &TLI) {
    3381         390 :     return promoteOperandForOther(Ext, TPT, PromotedInsts, CreatedInstsCost,
    3382         390 :                                   Exts, Truncs, TLI, true);
    3383             :   }
    3384             : 
    3385             :   /// \see promoteOperandForOther.
    3386        1779 :   static Value *zeroExtendOperandForOther(
    3387             :       Instruction *Ext, TypePromotionTransaction &TPT,
    3388             :       InstrToOrigTy &PromotedInsts, unsigned &CreatedInstsCost,
    3389             :       SmallVectorImpl<Instruction *> *Exts,
    3390             :       SmallVectorImpl<Instruction *> *Truncs, const TargetLowering &TLI) {
    3391        1779 :     return promoteOperandForOther(Ext, TPT, PromotedInsts, CreatedInstsCost,
    3392        1779 :                                   Exts, Truncs, TLI, false);
    3393             :   }
    3394             : 
    3395             : public:
    3396             :   /// Type for the utility function that promotes the operand of Ext.
    3397             :   using Action = Value *(*)(Instruction *Ext, TypePromotionTransaction &TPT,
    3398             :                             InstrToOrigTy &PromotedInsts,
    3399             :                             unsigned &CreatedInstsCost,
    3400             :                             SmallVectorImpl<Instruction *> *Exts,
    3401             :                             SmallVectorImpl<Instruction *> *Truncs,
    3402             :                             const TargetLowering &TLI);
    3403             : 
    3404             :   /// Given a sign/zero extend instruction \p Ext, return the appropriate
    3405             :   /// action to promote the operand of \p Ext instead of using Ext.
    3406             :   /// \return NULL if no promotable action is possible with the current
    3407             :   /// sign extension.
    3408             :   /// \p InsertedInsts keeps track of all the instructions inserted by the
    3409             :   /// other CodeGenPrepare optimizations. This information is important
    3410             :   /// because we do not want to promote these instructions as CodeGenPrepare
    3411             :   /// will reinsert them later. Thus creating an infinite loop: create/remove.
    3412             :   /// \p PromotedInsts maps the instructions to their type before promotion.
    3413             :   static Action getAction(Instruction *Ext, const SetOfInstrs &InsertedInsts,
    3414             :                           const TargetLowering &TLI,
    3415             :                           const InstrToOrigTy &PromotedInsts);
    3416             : };
    3417             : 
    3418             : } // end anonymous namespace
    3419             : 
    3420       14462 : bool TypePromotionHelper::canGetThrough(const Instruction *Inst,
    3421             :                                         Type *ConsideredExtType,
    3422             :                                         const InstrToOrigTy &PromotedInsts,
    3423             :                                         bool IsSExt) {
    3424             :   // The promotion helper does not know how to deal with vector types yet.
    3425             :   // To be able to fix that, we would need to fix the places where we
    3426             :   // statically extend, e.g., constants and such.
    3427       28924 :   if (Inst->getType()->isVectorTy())
    3428             :     return false;
    3429             : 
    3430             :   // We can always get through zext.
    3431       10133 :   if (isa<ZExtInst>(Inst))
    3432             :     return true;
    3433             : 
    3434             :   // sext(sext) is ok too.
    3435        9886 :   if (IsSExt && isa<SExtInst>(Inst))
    3436             :     return true;
    3437             : 
    3438             :   // We can get through binary operator, if it is legal. In other words, the
    3439             :   // binary operator must have a nuw or nsw flag.
    3440             :   const BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Inst);
    3441        1770 :   if (BinOp && isa<OverflowingBinaryOperator>(BinOp) &&
    3442        1770 :       ((!IsSExt && BinOp->hasNoUnsignedWrap()) ||
    3443         493 :        (IsSExt && BinOp->hasNoSignedWrap())))
    3444         811 :     return true;
    3445             : 
    3446             :   // ext(and(opnd, cst)) --> and(ext(opnd), ext(cst))
    3447        9068 :   if ((Inst->getOpcode() == Instruction::And ||
    3448             :        Inst->getOpcode() == Instruction::Or))
    3449             :     return true;
    3450             : 
    3451             :   // ext(xor(opnd, cst)) --> xor(ext(opnd), ext(cst))
    3452        8480 :   if (Inst->getOpcode() == Instruction::Xor) {
    3453         935 :     const ConstantInt *Cst = dyn_cast<ConstantInt>(Inst->getOperand(1));
    3454             :     // Make sure it is not a NOT.
    3455         873 :     if (Cst && !Cst->getValue().isAllOnesValue())
    3456             :       return true;
    3457             :   }
    3458             : 
    3459             :   // zext(shrl(opnd, cst)) --> shrl(zext(opnd), zext(cst))
    3460             :   // It may change a poisoned value into a regular value, like
    3461             :   //     zext i32 (shrl i8 %val, 12)  -->  shrl i32 (zext i8 %val), 12
    3462             :   //          poisoned value                    regular value
    3463             :   // It should be OK since undef covers valid value.
    3464        8471 :   if (Inst->getOpcode() == Instruction::LShr && !IsSExt)
    3465             :     return true;
    3466             : 
    3467             :   // and(ext(shl(opnd, cst)), cst) --> and(shl(ext(opnd), ext(cst)), cst)
    3468             :   // It may change a poisoned value into a regular value, like
    3469             :   //     zext i32 (shl i8 %val, 12)  -->  shl i32 (zext i8 %val), 12
    3470             :   //          poisoned value                    regular value
    3471             :   // It should be OK since undef covers valid value.
    3472        7782 :   if (Inst->getOpcode() == Instruction::Shl && Inst->hasOneUse()) {
    3473             :     const Instruction *ExtInst =
    3474             :         dyn_cast<const Instruction>(*Inst->user_begin());
    3475          51 :     if (ExtInst->hasOneUse()) {
    3476             :       const Instruction *AndInst =
    3477             :           dyn_cast<const Instruction>(*ExtInst->user_begin());
    3478          50 :       if (AndInst && AndInst->getOpcode() == Instruction::And) {
    3479           5 :         const ConstantInt *Cst = dyn_cast<ConstantInt>(AndInst->getOperand(1));
    3480           5 :         if (Cst &&
    3481           5 :             Cst->getValue().isIntN(Inst->getType()->getIntegerBitWidth()))
    3482             :           return true;
    3483             :       }
    3484             :     }
    3485             :   }
    3486             : 
    3487             :   // Check if we can do the following simplification.
    3488             :   // ext(trunc(opnd)) --> ext(opnd)
    3489        7710 :   if (!isa<TruncInst>(Inst))
    3490             :     return false;
    3491             : 
    3492        1118 :   Value *OpndVal = Inst->getOperand(0);
    3493             :   // Check if we can use this operand in the extension.
    3494             :   // If the type is larger than the result type of the extension, we cannot.
    3495        2236 :   if (!OpndVal->getType()->isIntegerTy() ||
    3496             :       OpndVal->getType()->getIntegerBitWidth() >
    3497             :           ConsideredExtType->getIntegerBitWidth())
    3498             :     return false;
    3499             : 
    3500             :   // If the operand of the truncate is not an instruction, we will not have
    3501             :   // any information on the dropped bits.
    3502             :   // (Actually we could for constant but it is not worth the extra logic).
    3503             :   Instruction *Opnd = dyn_cast<Instruction>(OpndVal);
    3504             :   if (!Opnd)
    3505             :     return false;
    3506             : 
    3507             :   // Check if the source of the type is narrow enough.
    3508             :   // I.e., check that trunc just drops extended bits of the same kind of
    3509             :   // the extension.
    3510             :   // #1 get the type of the operand and check the kind of the extended bits.
    3511         965 :   const Type *OpndType = getOrigType(PromotedInsts, Opnd, IsSExt);
    3512         965 :   if (OpndType)
    3513             :     ;
    3514         920 :   else if ((IsSExt && isa<SExtInst>(Opnd)) || (!IsSExt && isa<ZExtInst>(Opnd)))
    3515         636 :     OpndType = Opnd->getOperand(0)->getType();
    3516             :   else
    3517             :     return false;
    3518             : 
    3519             :   // #2 check that the truncate just drops extended bits.
    3520         363 :   return Inst->getType()->getIntegerBitWidth() >=
    3521         363 :          OpndType->getIntegerBitWidth();
    3522             : }
    3523             : 
    3524       18611 : TypePromotionHelper::Action TypePromotionHelper::getAction(
    3525             :     Instruction *Ext, const SetOfInstrs &InsertedInsts,
    3526             :     const TargetLowering &TLI, const InstrToOrigTy &PromotedInsts) {
    3527             :   assert((isa<SExtInst>(Ext) || isa<ZExtInst>(Ext)) &&
    3528             :          "Unexpected instruction type");
    3529       18611 :   Instruction *ExtOpnd = dyn_cast<Instruction>(Ext->getOperand(0));
    3530       18611 :   Type *ExtTy = Ext->getType();
    3531             :   bool IsSExt = isa<SExtInst>(Ext);
    3532             :   // If the operand of the extension is not an instruction, we cannot
    3533             :   // get through.
    3534             :   // If it, check we can get through.
    3535       18611 :   if (!ExtOpnd || !canGetThrough(ExtOpnd, ExtTy, PromotedInsts, IsSExt))
    3536       15827 :     return nullptr;
    3537             : 
    3538             :   // Do not promote if the operand has been added by codegenprepare.
    3539             :   // Otherwise, it means we are undoing an optimization that is likely to be
    3540             :   // redone, thus causing potential infinite loop.
    3541        2784 :   if (isa<TruncInst>(ExtOpnd) && InsertedInsts.count(ExtOpnd))
    3542             :     return nullptr;
    3543             : 
    3544             :   // SExt or Trunc instructions.
    3545             :   // Return the related handler.
    3546        2475 :   if (isa<SExtInst>(ExtOpnd) || isa<TruncInst>(ExtOpnd) ||
    3547             :       isa<ZExtInst>(ExtOpnd))
    3548             :     return promoteOperandForTruncAndAnyExt;
    3549             : 
    3550             :   // Regular instruction.
    3551             :   // Abort early if we will have to insert non-free instructions.
    3552        2169 :   if (!ExtOpnd->hasOneUse() && !TLI.isTruncateFree(ExtTy, ExtOpnd->getType()))
    3553             :     return nullptr;
    3554        2169 :   return IsSExt ? signExtendOperandForOther : zeroExtendOperandForOther;
    3555             : }
    3556             : 
    3557         306 : Value *TypePromotionHelper::promoteOperandForTruncAndAnyExt(
    3558             :     Instruction *SExt, TypePromotionTransaction &TPT,
    3559             :     InstrToOrigTy &PromotedInsts, unsigned &CreatedInstsCost,
    3560             :     SmallVectorImpl<Instruction *> *Exts,
    3561             :     SmallVectorImpl<Instruction *> *Truncs, const TargetLowering &TLI) {
    3562             :   // By construction, the operand of SExt is an instruction. Otherwise we cannot
    3563             :   // get through it and this method should not be called.
    3564         306 :   Instruction *SExtOpnd = cast<Instruction>(SExt->getOperand(0));
    3565             :   Value *ExtVal = SExt;
    3566             :   bool HasMergedNonFreeExt = false;
    3567         306 :   if (isa<ZExtInst>(SExtOpnd)) {
    3568             :     // Replace s|zext(zext(opnd))
    3569             :     // => zext(opnd).
    3570         247 :     HasMergedNonFreeExt = !TLI.isExtFree(SExtOpnd);
    3571             :     Value *ZExt =
    3572         494 :         TPT.createZExt(SExt, SExtOpnd->getOperand(0), SExt->getType());
    3573         247 :     TPT.replaceAllUsesWith(SExt, ZExt);
    3574         247 :     TPT.eraseInstruction(SExt);
    3575             :     ExtVal = ZExt;
    3576             :   } else {
    3577             :     // Replace z|sext(trunc(opnd)) or sext(sext(opnd))
    3578             :     // => z|sext(opnd).
    3579         118 :     TPT.setOperand(SExt, 0, SExtOpnd->getOperand(0));
    3580             :   }
    3581         306 :   CreatedInstsCost = 0;
    3582             : 
    3583             :   // Remove dead code.
    3584         306 :   if (SExtOpnd->use_empty())
    3585         211 :     TPT.eraseInstruction(SExtOpnd);
    3586             : 
    3587             :   // Check if the extension is still needed.
    3588         306 :   Instruction *ExtInst = dyn_cast<Instruction>(ExtVal);
    3589         610 :   if (!ExtInst || ExtInst->getType() != ExtInst->getOperand(0)->getType()) {
    3590         269 :     if (ExtInst) {
    3591         267 :       if (Exts)
    3592         255 :         Exts->push_back(ExtInst);
    3593         522 :       CreatedInstsCost = !TLI.isExtFree(ExtInst) && !HasMergedNonFreeExt;
    3594             :     }
    3595         269 :     return ExtVal;
    3596             :   }
    3597             : 
    3598             :   // At this point we have: ext ty opnd to ty.
    3599             :   // Reassign the uses of ExtInst to the opnd and remove ExtInst.
    3600             :   Value *NextVal = ExtInst->getOperand(0);
    3601          37 :   TPT.eraseInstruction(ExtInst, NextVal);
    3602          37 :   return NextVal;
    3603             : }
    3604             : 
    3605        2169 : Value *TypePromotionHelper::promoteOperandForOther(
    3606             :     Instruction *Ext, TypePromotionTransaction &TPT,
    3607             :     InstrToOrigTy &PromotedInsts, unsigned &CreatedInstsCost,
    3608             :     SmallVectorImpl<Instruction *> *Exts,
    3609             :     SmallVectorImpl<Instruction *> *Truncs, const TargetLowering &TLI,
    3610             :     bool IsSExt) {
    3611             :   // By construction, the operand of Ext is an instruction. Otherwise we cannot
    3612             :   // get through it and this method should not be called.
    3613        2169 :   Instruction *ExtOpnd = cast<Instruction>(Ext->getOperand(0));
    3614        2169 :   CreatedInstsCost = 0;
    3615        2169 :   if (!ExtOpnd->hasOneUse()) {
    3616             :     // ExtOpnd will be promoted.
    3617             :     // All its uses, but Ext, will need to use a truncated value of the
    3618             :     // promoted version.
    3619             :     // Create the truncate now.
    3620         173 :     Value *Trunc = TPT.createTrunc(Ext, ExtOpnd->getType());
    3621         173 :     if (Instruction *ITrunc = dyn_cast<Instruction>(Trunc)) {
    3622             :       // Insert it just after the definition.
    3623         173 :       ITrunc->moveAfter(ExtOpnd);
    3624         173 :       if (Truncs)
    3625           0 :         Truncs->push_back(ITrunc);
    3626             :     }
    3627             : 
    3628         173 :     TPT.replaceAllUsesWith(ExtOpnd, Trunc);
    3629             :     // Restore the operand of Ext (which has been replaced by the previous call
    3630             :     // to replaceAllUsesWith) to avoid creating a cycle trunc <-> sext.
    3631         173 :     TPT.setOperand(Ext, 0, ExtOpnd);
    3632             :   }
    3633             : 
    3634             :   // Get through the Instruction:
    3635             :   // 1. Update its type.
    3636             :   // 2. Replace the uses of Ext by Inst.
    3637             :   // 3. Extend each operand that needs to be extended.
    3638             : 
    3639             :   // Remember the original type of the instruction before promotion.
    3640             :   // This is useful to know that the high bits are sign extended bits.
    3641        2169 :   addPromotedInst(PromotedInsts, ExtOpnd, IsSExt);
    3642             :   // Step #1.
    3643        2169 :   TPT.mutateType(ExtOpnd, Ext->getType());
    3644             :   // Step #2.
    3645        2169 :   TPT.replaceAllUsesWith(Ext, ExtOpnd);
    3646             :   // Step #3.
    3647        2169 :   Instruction *ExtForOpnd = Ext;
    3648             : 
    3649             :   LLVM_DEBUG(dbgs() << "Propagate Ext to operands\n");
    3650        6507 :   for (int OpIdx = 0, EndOpIdx = ExtOpnd->getNumOperands(); OpIdx != EndOpIdx;
    3651             :        ++OpIdx) {
    3652             :     LLVM_DEBUG(dbgs() << "Operand:\n" << *(ExtOpnd->getOperand(OpIdx)) << '\n');
    3653        8676 :     if (ExtOpnd->getOperand(OpIdx)->getType() == Ext->getType() ||
    3654             :         !shouldExtOperand(ExtOpnd, OpIdx)) {
    3655             :       LLVM_DEBUG(dbgs() << "No need to propagate\n");
    3656             :       continue;
    3657             :     }
    3658             :     // Check if we can statically extend the operand.
    3659             :     Value *Opnd = ExtOpnd->getOperand(OpIdx);
    3660             :     if (const ConstantInt *Cst = dyn_cast<ConstantInt>(Opnd)) {
    3661             :       LLVM_DEBUG(dbgs() << "Statically extend\n");
    3662             :       unsigned BitWidth = Ext->getType()->getIntegerBitWidth();
    3663             :       APInt CstVal = IsSExt ? Cst->getValue().sext(BitWidth)
    3664        1819 :                             : Cst->getValue().zext(BitWidth);
    3665        1819 :       TPT.setOperand(ExtOpnd, OpIdx, ConstantInt::get(Ext->getType(), CstVal));
    3666             :       continue;
    3667             :     }
    3668             :     // UndefValue are typed, so we have to statically sign extend them.
    3669        2519 :     if (isa<UndefValue>(Opnd)) {
    3670             :       LLVM_DEBUG(dbgs() << "Statically extend\n");
    3671           0 :       TPT.setOperand(ExtOpnd, OpIdx, UndefValue::get(Ext->getType()));
    3672           0 :       continue;
    3673             :     }
    3674             : 
    3675             :     // Otherwise we have to explicitly sign extend the operand.
    3676             :     // Check if Ext was reused to extend an operand.
    3677        2519 :     if (!ExtForOpnd) {
    3678             :       // If yes, create a new one.
    3679             :       LLVM_DEBUG(dbgs() << "More operands to ext\n");
    3680         350 :       Value *ValForExtOpnd = IsSExt ? TPT.createSExt(Ext, Opnd, Ext->getType())
    3681         247 :         : TPT.createZExt(Ext, Opnd, Ext->getType());
    3682         350 :       if (!isa<Instruction>(ValForExtOpnd)) {
    3683           6 :         TPT.setOperand(ExtOpnd, OpIdx, ValForExtOpnd);
    3684             :         continue;
    3685             :       }
    3686         344 :       ExtForOpnd = cast<Instruction>(ValForExtOpnd);
    3687             :     }
    3688        2513 :     if (Exts)
    3689        2235 :       Exts->push_back(ExtForOpnd);
    3690        2513 :     TPT.setOperand(ExtForOpnd, 0, Opnd);
    3691             : 
    3692             :     // Move the sign extension before the insertion point.
    3693        2513 :     TPT.moveBefore(ExtForOpnd, ExtOpnd);
    3694        2513 :     TPT.setOperand(ExtOpnd, OpIdx, ExtForOpnd);
    3695        2513 :     CreatedInstsCost += !TLI.isExtFree(ExtForOpnd);
    3696             :     // If more sext are required, new instructions will have to be created.
    3697        2513 :     ExtForOpnd = nullptr;
    3698             :   }
    3699        2169 :   if (ExtForOpnd == Ext) {
    3700             :     LLVM_DEBUG(dbgs() << "Extension is useless now\n");
    3701           0 :     TPT.eraseInstruction(Ext);
    3702             :   }
    3703        2169 :   return ExtOpnd;
    3704             : }
    3705             : 
    3706             : /// Check whether or not promoting an instruction to a wider type is profitable.
    3707             : /// \p NewCost gives the cost of extension instructions created by the
    3708             : /// promotion.
    3709             : /// \p OldCost gives the cost of extension instructions before the promotion
    3710             : /// plus the number of instructions that have been
    3711             : /// matched in the addressing mode the promotion.
    3712             : /// \p PromotedOperand is the value that has been promoted.
    3713             : /// \return True if the promotion is profitable, false otherwise.
    3714           0 : bool AddressingModeMatcher::isPromotionProfitable(
    3715             :     unsigned NewCost, unsigned OldCost, Value *PromotedOperand) const {
    3716             :   LLVM_DEBUG(dbgs() << "OldCost: " << OldCost << "\tNewCost: " << NewCost
    3717             :                     << '\n');
    3718             :   // The cost of the new extensions is greater than the cost of the
    3719             :   // old extension plus what we folded.
    3720             :   // This is not profitable.
    3721           0 :   if (NewCost > OldCost)
    3722           0 :     return false;
    3723         195 :   if (NewCost < OldCost)
    3724           0 :     return true;
    3725             :   // The promotion is neutral but it may help folding the sign extension in
    3726             :   // loads for instance.
    3727             :   // Check that we did not create an illegal instruction.
    3728         105 :   return isPromotedInstructionLegal(TLI, DL, PromotedOperand);
    3729             : }
    3730             : 
    3731             : /// Given an instruction or constant expr, see if we can fold the operation
    3732             : /// into the addressing mode. If so, update the addressing mode and return
    3733             : /// true, otherwise return false without modifying AddrMode.
    3734             : /// If \p MovedAway is not NULL, it contains the information of whether or
    3735             : /// not AddrInst has to be folded into the addressing mode on success.
    3736             : /// If \p MovedAway == true, \p AddrInst will not be part of the addressing
    3737             : /// because it has been moved away.
    3738             : /// Thus AddrInst must not be added in the matched instructions.
    3739             : /// This state can happen when AddrInst is a sext, since it may be moved away.
    3740             : /// Therefore, AddrInst may not be valid when MovedAway is true and it must
    3741             : /// not be referenced anymore.
    3742     2227831 : bool AddressingModeMatcher::matchOperationAddr(User *AddrInst, unsigned Opcode,
    3743             :                                                unsigned Depth,
    3744             :                                                bool *MovedAway) {
    3745             :   // Avoid exponential behavior on extremely deep expression trees.
    3746     2227831 :   if (Depth >= 5) return false;
    3747             : 
    3748             :   // By default, all matched instructions stay in place.
    3749     2227731 :   if (MovedAway)
    3750      739020 :     *MovedAway = false;
    3751             : 
    3752     2227731 :   switch (Opcode) {
    3753         518 :   case Instruction::PtrToInt:
    3754             :     // PtrToInt is always a noop, as we know that the int type is pointer sized.
    3755         518 :     return matchAddr(AddrInst->getOperand(0), Depth);
    3756        4802 :   case Instruction::IntToPtr: {
    3757        4802 :     auto AS = AddrInst->getType()->getPointerAddressSpace();
    3758        4802 :     auto PtrTy = MVT::getIntegerVT(DL.getPointerSizeInBits(AS));
    3759             :     // This inttoptr is a no-op if the integer type is pointer sized.
    3760       14406 :     if (TLI.getValueType(DL, AddrInst->getOperand(0)->getType()) == PtrTy)
    3761        4739 :       return matchAddr(AddrInst->getOperand(0), Depth);
    3762             :     return false;
    3763             :   }
    3764      588626 :   case Instruction::BitCast:
    3765             :     // BitCast is always a noop, and we can handle it as long as it is
    3766             :     // int->int or pointer->pointer (we don't want int<->fp or something).
    3767      588626 :     if (AddrInst->getOperand(0)->getType()->isIntOrPtrTy() &&
    3768             :         // Don't touch identity bitcasts.  These were probably put here by LSR,
    3769             :         // and we don't want to mess around with them.  Assume it knows what it
    3770             :         // is doing.
    3771      588622 :         AddrInst->getOperand(0)->getType() != AddrInst->getType())
    3772      583140 :       return matchAddr(AddrInst->getOperand(0), Depth);
    3773             :     return false;
    3774         312 :   case Instruction::AddrSpaceCast: {
    3775             :     unsigned SrcAS
    3776         312 :       = AddrInst->getOperand(0)->getType()->getPointerAddressSpace();
    3777         312 :     unsigned DestAS = AddrInst->getType()->getPointerAddressSpace();
    3778         312 :     if (TLI.isNoopAddrSpaceCast(SrcAS, DestAS))
    3779         104 :       return matchAddr(AddrInst->getOperand(0), Depth);
    3780             :     return false;
    3781             :   }
    3782        3346 :   case Instruction::Add: {
    3783             :     // Check to see if we can merge in the RHS then the LHS.  If so, we win.
    3784        3346 :     ExtAddrMode BackupAddrMode = AddrMode;
    3785        3346 :     unsigned OldSize = AddrModeInsts.size();
    3786             :     // Start a transaction at this point.
    3787             :     // The LHS may match but not the RHS.
    3788             :     // Therefore, we need a higher level restoration point to undo partially
    3789             :     // matched operation.
    3790             :     TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    3791        3346 :         TPT.getRestorationPoint();
    3792             : 
    3793        9713 :     if (matchAddr(AddrInst->getOperand(1), Depth+1) &&
    3794        3021 :         matchAddr(AddrInst->getOperand(0), Depth+1))
    3795             :       return true;
    3796             : 
    3797             :     // Restore the old addr mode info.
    3798         846 :     AddrMode = BackupAddrMode;
    3799         846 :     AddrModeInsts.resize(OldSize);
    3800         846 :     TPT.rollback(LastKnownGood);
    3801             : 
    3802             :     // Otherwise this was over-aggressive.  Try merging in the LHS then the RHS.
    3803        1176 :     if (matchAddr(AddrInst->getOperand(0), Depth+1) &&
    3804         330 :         matchAddr(AddrInst->getOperand(1), Depth+1))
    3805             :       return true;
    3806             : 
    3807             :     // Otherwise we definitely can't merge the ADD in.
    3808         845 :     AddrMode = BackupAddrMode;
    3809         845 :     AddrModeInsts.resize(OldSize);
    3810         845 :     TPT.rollback(LastKnownGood);
    3811             :     break;
    3812             :   }
    3813             :   //case Instruction::Or:
    3814             :   // TODO: We can handle "Or Val, Imm" iff this OR is equivalent to an ADD.
    3815             :   //break;
    3816        3835 :   case Instruction::Mul:
    3817             :   case Instruction::Shl: {
    3818             :     // Can only handle X*C and X << C.
    3819             :     ConstantInt *RHS = dyn_cast<ConstantInt>(AddrInst->getOperand(1));
    3820        3597 :     if (!RHS || RHS->getBitWidth() > 64)
    3821             :       return false;
    3822             :     int64_t Scale = RHS->getSExtValue();
    3823        3596 :     if (Opcode == Instruction::Shl)
    3824        1835 :       Scale = 1LL << Scale;
    3825             : 
    3826        3596 :     return matchScaledValue(AddrInst->getOperand(0), Scale, Depth);
    3827             :   }
    3828     1351625 :   case Instruction::GetElementPtr: {
    3829             :     // Scan the GEP.  We check it if it contains constant offsets and at most
    3830             :     // one variable offset.
    3831             :     int VariableOperand = -1;
    3832             :     unsigned VariableScale = 0;
    3833             : 
    3834             :     int64_t ConstantOffset = 0;
    3835     1351625 :     gep_type_iterator GTI = gep_type_begin(AddrInst);
    3836     3983397 :     for (unsigned i = 1, e = AddrInst->getNumOperands(); i != e; ++i, ++GTI) {
    3837      139880 :       if (StructType *STy = GTI.getStructTypeOrNull()) {
    3838      139880 :         const StructLayout *SL = DL.getStructLayout(STy);
    3839             :         unsigned Idx =
    3840      139880 :           cast<ConstantInt>(AddrInst->getOperand(i))->getZExtValue();
    3841      139880 :         ConstantOffset += SL->getElementOffset(Idx);
    3842             :       } else {
    3843     2492831 :         uint64_t TypeSize = DL.getTypeAllocSize(GTI.getIndexedType());
    3844             :         if (ConstantInt *CI = dyn_cast<ConstantInt>(AddrInst->getOperand(i))) {
    3845             :           const APInt &CVal = CI->getValue();
    3846     2443429 :           if (CVal.getMinSignedBits() <= 64) {
    3847     2443427 :             ConstantOffset += CVal.getSExtValue() * TypeSize;
    3848     2443427 :             continue;
    3849             :           }
    3850             :         }
    3851       49404 :         if (TypeSize) {  // Scales of zero don't do anything.
    3852             :           // We only allow one variable index at the moment.
    3853       49395 :           if (VariableOperand != -1)
    3854             :             return false;
    3855             : 
    3856             :           // Remember the variable index.
    3857       48456 :           VariableOperand = i;
    3858       48456 :           VariableScale = TypeSize;
    3859             :         }
    3860             :       }
    3861             :     }
    3862             : 
    3863             :     // A common case is for the GEP to only do a constant offset.  In this case,
    3864             :     // just add it to the disp field and check validity.
    3865     1350686 :     if (VariableOperand == -1) {
    3866     1303169 :       AddrMode.BaseOffs += ConstantOffset;
    3867     2467646 :       if (ConstantOffset == 0 ||
    3868     1164477 :           TLI.isLegalAddressingMode(DL, AddrMode, AccessTy, AddrSpace)) {
    3869             :         // Check to see if we can fold the base pointer in too.
    3870     2599000 :         if (matchAddr(AddrInst->getOperand(0), Depth+1))
    3871             :           return true;
    3872        3542 :       } else if (EnableGEPOffsetSplit && isa<GetElementPtrInst>(AddrInst) &&
    3873        7485 :                  TLI.shouldConsiderGEPOffsetSplit() && Depth == 0 &&
    3874             :                  ConstantOffset > 0) {
    3875             :         // Record GEPs with non-zero offsets as candidates for splitting in the
    3876             :         // event that the offset cannot fit into the r+i addressing mode.
    3877             :         // Simple and common case that only one GEP is used in calculating the
    3878             :         // address for the memory access.
    3879             :         Value *Base = AddrInst->getOperand(0);
    3880             :         auto *BaseI = dyn_cast<Instruction>(Base);
    3881             :         auto *GEP = cast<GetElementPtrInst>(AddrInst);
    3882         311 :         if (isa<Argument>(Base) || isa<GlobalValue>(Base) ||
    3883          71 :             (BaseI && !isa<CastInst>(BaseI) &&
    3884             :              !isa<GetElementPtrInst>(BaseI))) {
    3885             :           // If the base is an instruction, make sure the GEP is not in the same
    3886             :           // basic block as the base. If the base is an argument or global
    3887             :           // value, make sure the GEP is not in the entry block.  Otherwise,
    3888             :           // instruction selection can undo the split.  Also make sure the
    3889             :           // parent block allows inserting non-PHI instructions before the
    3890             :           // terminator.
    3891             :           BasicBlock *Parent =
    3892         205 :               BaseI ? BaseI->getParent() : &GEP->getFunction()->getEntryBlock();
    3893         205 :           if (GEP->getParent() != Parent && !Parent->getTerminator()->isEHPad())
    3894          28 :             LargeOffsetGEP = std::make_pair(GEP, ConstantOffset);
    3895             :         }
    3896             :       }
    3897        3669 :       AddrMode.BaseOffs -= ConstantOffset;
    3898        3669 :       return false;
    3899             :     }
    3900             : 
    3901             :     // Save the valid addressing mode in case we can't match.
    3902       47517 :     ExtAddrMode BackupAddrMode = AddrMode;
    3903       47517 :     unsigned OldSize = AddrModeInsts.size();
    3904             : 
    3905             :     // See if the scale and offset amount is valid for this target.
    3906       47517 :     AddrMode.BaseOffs += ConstantOffset;
    3907             : 
    3908             :     // Match the base operand of the GEP.
    3909       95034 :     if (!matchAddr(AddrInst->getOperand(0), Depth+1)) {
    3910             :       // If it couldn't be matched, just stuff the value in a register.
    3911           5 :       if (AddrMode.HasBaseReg) {
    3912           0 :         AddrMode = BackupAddrMode;
    3913           0 :         AddrModeInsts.resize(OldSize);
    3914           0 :         return false;
    3915             :       }
    3916           5 :       AddrMode.HasBaseReg = true;
    3917           5 :       AddrMode.BaseReg = AddrInst->getOperand(0);
    3918             :     }
    3919             : 
    3920             :     // Match the remaining variable portion of the GEP.
    3921       95034 :     if (!matchScaledValue(AddrInst->getOperand(VariableOperand), VariableScale,
    3922             :                           Depth)) {
    3923             :       // If it couldn't be matched, try stuffing the base into a register
    3924             :       // instead of matching it, and retrying the match of the scale.
    3925       17534 :       AddrMode = BackupAddrMode;
    3926       17534 :       AddrModeInsts.resize(OldSize);
    3927       17534 :       if (AddrMode.HasBaseReg)
    3928             :         return false;
    3929       17525 :       AddrMode.HasBaseReg = true;
    3930       17525 :       AddrMode.BaseReg = AddrInst->getOperand(0);
    3931       17525 :       AddrMode.BaseOffs += ConstantOffset;
    3932       17525 :       if (!matchScaledValue(AddrInst->getOperand(VariableOperand),
    3933             :                             VariableScale, Depth)) {
    3934             :         // If even that didn't work, bail.
    3935       16264 :         AddrMode = BackupAddrMode;
    3936       16264 :         AddrModeInsts.resize(OldSize);
    3937       16264 :         return false;
    3938             :       }
    3939             :     }
    3940             : 
    3941             :     return true;
    3942             :   }
    3943        1303 :   case Instruction::SExt:
    3944             :   case Instruction::ZExt: {
    3945             :     Instruction *Ext = dyn_cast<Instruction>(AddrInst);
    3946             :     if (!Ext)
    3947             :       return false;
    3948             : 
    3949             :     // Try to move this ext out of the way of the addressing mode.
    3950             :     // Ask for a method for doing so.
    3951             :     TypePromotionHelper::Action TPH =
    3952        1302 :         TypePromotionHelper::getAction(Ext, InsertedInsts, TLI, PromotedInsts);
    3953        1302 :     if (!TPH)
    3954             :       return false;
    3955             : 
    3956             :     TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    3957         274 :         TPT.getRestorationPoint();
    3958         274 :     unsigned CreatedInstsCost = 0;
    3959         274 :     unsigned ExtCost = !TLI.isExtFree(Ext);
    3960             :     Value *PromotedOperand =
    3961         274 :         TPH(Ext, TPT, PromotedInsts, CreatedInstsCost, nullptr, nullptr, TLI);
    3962             :     // SExt has been moved away.
    3963             :     // Thus either it will be rematched later in the recursive calls or it is
    3964             :     // gone. Anyway, we must not fold it into the addressing mode at this point.
    3965             :     // E.g.,
    3966             :     // op = add opnd, 1
    3967             :     // idx = ext op
    3968             :     // addr = gep base, idx
    3969             :     // is now:
    3970             :     // promotedOpnd = ext opnd            <- no match here
    3971             :     // op = promoted_add promotedOpnd, 1  <- match (later in recursive calls)
    3972             :     // addr = gep base, op                <- match
    3973         274 :     if (MovedAway)
    3974         274 :       *MovedAway = true;
    3975             : 
    3976             :     assert(PromotedOperand &&
    3977             :            "TypePromotionHelper should have filtered out those cases");
    3978             : 
    3979         274 :     ExtAddrMode BackupAddrMode = AddrMode;
    3980         274 :     unsigned OldSize = AddrModeInsts.size();
    3981             : 
    3982         379 :     if (!matchAddr(PromotedOperand, Depth) ||
    3983             :         // The total of the new cost is equal to the cost of the created
    3984             :         // instructions.
    3985             :         // The total of the old cost is equal to the cost of the extension plus
    3986             :         // what we have saved in the addressing mode.
    3987         206 :         !isPromotionProfitable(CreatedInstsCost,
    3988         206 :                                ExtCost + (AddrModeInsts.size() - OldSize),
    3989             :                                PromotedOperand)) {
    3990         109 :       AddrMode = BackupAddrMode;
    3991         109 :       AddrModeInsts.resize(OldSize);
    3992             :       LLVM_DEBUG(dbgs() << "Sign extension does not pay off: rollback\n");
    3993         109 :       TPT.rollback(LastKnownGood);
    3994         109 :       return false;
    3995             :     }
    3996             :     return true;
    3997             :   }
    3998             :   }
    3999             :   return false;
    4000             : }
    4001             : 
    4002             : /// If we can, try to add the value of 'Addr' into the current addressing mode.
    4003             : /// If Addr can't be added to AddrMode this returns false and leaves AddrMode
    4004             : /// unmodified. This assumes that Addr is either a pointer type or intptr_t
    4005             : /// for the target.
    4006             : ///
    4007     3898032 : bool AddressingModeMatcher::matchAddr(Value *Addr, unsigned Depth) {
    4008             :   // Start a transaction at this point that we will rollback if the matching
    4009             :   // fails.
    4010             :   TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    4011     3898032 :       TPT.getRestorationPoint();
    4012             :   if (ConstantInt *CI = dyn_cast<ConstantInt>(Addr)) {
    4013             :     // Fold in immediates if legal for the target.
    4014        2689 :     AddrMode.BaseOffs += CI->getSExtValue();
    4015        2689 :     if (TLI.isLegalAddressingMode(DL, AddrMode, AccessTy, AddrSpace))
    4016             :       return true;
    4017         732 :     AddrMode.BaseOffs -= CI->getSExtValue();
    4018             :   } else if (GlobalValue *GV = dyn_cast<GlobalValue>(Addr)) {
    4019             :     // If this is a global variable, try to fold it into the addressing mode.
    4020     1508582 :     if (!AddrMode.BaseGV) {
    4021     1508582 :       AddrMode.BaseGV = GV;
    4022     1508582 :       if (TLI.isLegalAddressingMode(DL, AddrMode, AccessTy, AddrSpace))
    4023             :         return true;
    4024      562757 :       AddrMode.BaseGV = nullptr;
    4025             :     }
    4026     2386761 :   } else if (Instruction *I = dyn_cast<Instruction>(Addr)) {
    4027      739120 :     ExtAddrMode BackupAddrMode = AddrMode;
    4028      739120 :     unsigned OldSize = AddrModeInsts.size();
    4029             : 
    4030             :     // Check to see if it is possible to fold this operation.
    4031      739120 :     bool MovedAway = false;
    4032      739120 :     if (matchOperationAddr(I, I->getOpcode(), Depth, &MovedAway)) {
    4033             :       // This instruction may have been moved away. If so, there is nothing
    4034             :       // to check here.
    4035      435450 :       if (MovedAway)
    4036      427055 :         return true;
    4037             :       // Okay, it's possible to fold this.  Check to see if it is actually
    4038             :       // *profitable* to do so.  We use a simple cost model to avoid increasing
    4039             :       // register pressure too much.
    4040      505838 :       if (I->hasOneUse() ||
    4041       70553 :           isProfitableToFoldIntoAddressingMode(I, BackupAddrMode, AddrMode)) {
    4042      426890 :         AddrModeInsts.push_back(I);
    4043      426890 :         return true;
    4044             :       }
    4045             : 
    4046             :       // It isn't profitable to do this, roll back.
    4047             :       //cerr << "NOT FOLDING: " << *I;
    4048        8395 :       AddrMode = BackupAddrMode;
    4049        8395 :       AddrModeInsts.resize(OldSize);
    4050        8395 :       TPT.rollback(LastKnownGood);
    4051             :     }
    4052             :   } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Addr)) {
    4053     1488711 :     if (matchOperationAddr(CE, CE->getOpcode(), Depth))
    4054             :       return true;
    4055         179 :     TPT.rollback(LastKnownGood);
    4056      158930 :   } else if (isa<ConstantPointerNull>(Addr)) {
    4057             :     // Null pointer gets folded without affecting the addressing mode.
    4058             :     return true;
    4059             :   }
    4060             : 
    4061             :   // Worse case, the target should support [reg] addressing modes. :)
    4062     1033178 :   if (!AddrMode.HasBaseReg) {
    4063     1009302 :     AddrMode.HasBaseReg = true;
    4064     1009302 :     AddrMode.BaseReg = Addr;
    4065             :     // Still check for legality in case the target supports [imm] but not [i+r].
    4066     1009302 :     if (TLI.isLegalAddressingMode(DL, AddrMode, AccessTy, AddrSpace))
    4067             :       return true;
    4068          10 :     AddrMode.HasBaseReg = false;
    4069          10 :     AddrMode.BaseReg = nullptr;
    4070             :   }
    4071             : 
    4072             :   // If the base register is already taken, see if we can do [r+r].
    4073       23886 :   if (AddrMode.Scale == 0) {
    4074       22734 :     AddrMode.Scale = 1;
    4075       22734 :     AddrMode.ScaledReg = Addr;
    4076       22734 :     if (TLI.isLegalAddressingMode(DL, AddrMode, AccessTy, AddrSpace))
    4077             :       return true;
    4078        3221 :     AddrMode.Scale = 0;
    4079        3221 :     AddrMode.ScaledReg = nullptr;
    4080             :   }
    4081             :   // Couldn't match.
    4082        4373 :   TPT.rollback(LastKnownGood);
    4083        4373 :   return false;
    4084             : }
    4085             : 
    4086             : /// Check to see if all uses of OpVal by the specified inline asm call are due
    4087             : /// to memory operands. If so, return true, otherwise return false.
    4088           0 : static bool IsOperandAMemoryOperand(CallInst *CI, InlineAsm *IA, Value *OpVal,
    4089             :                                     const TargetLowering &TLI,
    4090             :                                     const TargetRegisterInfo &TRI) {
    4091           0 :   const Function *F = CI->getFunction();
    4092             :   TargetLowering::AsmOperandInfoVector TargetConstraints =
    4093             :       TLI.ParseConstraints(F->getParent()->getDataLayout(), &TRI,
    4094           0 :                             ImmutableCallSite(CI));
    4095             : 
    4096           0 :   for (unsigned i = 0, e = TargetConstraints.size(); i != e; ++i) {
    4097           0 :     TargetLowering::AsmOperandInfo &OpInfo = TargetConstraints[i];
    4098             : 
    4099             :     // Compute the constraint code and ConstraintType to use.
    4100           0 :     TLI.ComputeConstraintToUse(OpInfo, SDValue());
    4101             : 
    4102             :     // If this asm operand is our Value*, and if it isn't an indirect memory
    4103             :     // operand, we can't fold it!
    4104           0 :     if (OpInfo.CallOperandVal == OpVal &&
    4105           0 :         (OpInfo.ConstraintType != TargetLowering::C_Memory ||
    4106           0 :          !OpInfo.isIndirect))
    4107           0 :       return false;
    4108             :   }
    4109             : 
    4110             :   return true;
    4111             : }
    4112             : 
    4113             : // Max number of memory uses to look at before aborting the search to conserve
    4114             : // compile time.
    4115             : static constexpr int MaxMemoryUsesToScan = 20;
    4116             : 
    4117             : /// Recursively walk all the uses of I until we find a memory use.
    4118             : /// If we find an obviously non-foldable instruction, return true.
    4119             : /// Add the ultimately found memory instructions to MemoryUses.
    4120       45775 : static bool FindAllMemoryUses(
    4121             :     Instruction *I,
    4122             :     SmallVectorImpl<std::pair<Instruction *, unsigned>> &MemoryUses,
    4123             :     SmallPtrSetImpl<Instruction *> &ConsideredInsts, const TargetLowering &TLI,
    4124             :     const TargetRegisterInfo &TRI, int SeenInsts = 0) {
    4125             :   // If we already considered this instruction, we're done.
    4126       45775 :   if (!ConsideredInsts.insert(I).second)
    4127             :     return false;
    4128             : 
    4129             :   // If this is an obviously unfoldable instruction, bail out.
    4130       45775 :   if (!MightBeFoldableInst(I))
    4131             :     return true;
    4132             : 
    4133       39934 :   const bool OptSize = I->getFunction()->optForSize();
    4134             : 
    4135             :   // Loop over all the uses, recursively processing them.
    4136      101627 :   for (Use &U : I->uses()) {
    4137             :     // Conservatively return true if we're seeing a large number or a deep chain
    4138             :     // of users. This avoids excessive compilation times in pathological cases.
    4139       71643 :     if (SeenInsts++ >= MaxMemoryUsesToScan)
    4140             :       return true;
    4141             : 
    4142       70877 :     Instruction *UserI = cast<Instruction>(U.getUser());
    4143             :     if (LoadInst *LI = dyn_cast<LoadInst>(UserI)) {
    4144       24847 :       MemoryUses.push_back(std::make_pair(LI, U.getOperandNo()));
    4145             :       continue;
    4146             :     }
    4147             : 
    4148             :     if (StoreInst *SI = dyn_cast<StoreInst>(UserI)) {
    4149       11298 :       unsigned opNo = U.getOperandNo();
    4150       11298 :       if (opNo != StoreInst::getPointerOperandIndex())
    4151             :         return true; // Storing addr, not into addr.
    4152       22390 :       MemoryUses.push_back(std::make_pair(SI, opNo));
    4153             :       continue;
    4154             :     }
    4155             : 
    4156             :     if (AtomicRMWInst *RMW = dyn_cast<AtomicRMWInst>(UserI)) {
    4157          54 :       unsigned opNo = U.getOperandNo();
    4158          54 :       if (opNo != AtomicRMWInst::getPointerOperandIndex())
    4159             :         return true; // Storing addr, not into addr.
    4160         108 :       MemoryUses.push_back(std::make_pair(RMW, opNo));
    4161             :       continue;
    4162             :     }
    4163             : 
    4164             :     if (AtomicCmpXchgInst *CmpX = dyn_cast<AtomicCmpXchgInst>(UserI)) {
    4165           3 :       unsigned opNo = U.getOperandNo();
    4166           3 :       if (opNo != AtomicCmpXchgInst::getPointerOperandIndex())
    4167             :         return true; // Storing addr, not into addr.
    4168           6 :       MemoryUses.push_back(std::make_pair(CmpX, opNo));
    4169             :       continue;
    4170             :     }
    4171             : 
    4172             :     if (CallInst *CI = dyn_cast<CallInst>(UserI)) {
    4173             :       // If this is a cold call, we can sink the addressing calculation into
    4174             :       // the cold path.  See optimizeCallInst
    4175         765 :       if (!OptSize && CI->hasFnAttr(Attribute::Cold))
    4176             :         continue;
    4177             : 
    4178             :       InlineAsm *IA = dyn_cast<InlineAsm>(CI->getCalledValue());
    4179             :       if (!IA) return true;
    4180             : 
    4181             :       // If this is a memory operand, we're cool, otherwise bail out.
    4182          14 :       if (!IsOperandAMemoryOperand(CI, IA, I, TLI, TRI))
    4183             :         return true;
    4184             :       continue;
    4185             :     }
    4186             : 
    4187       33910 :     if (FindAllMemoryUses(UserI, MemoryUses, ConsideredInsts, TLI, TRI,
    4188             :                           SeenInsts))
    4189             :       return true;
    4190             :   }
    4191             : 
    4192             :   return false;
    4193             : }
    4194             : 
    4195             : /// Return true if Val is already known to be live at the use site that we're
    4196             : /// folding it into. If so, there is no cost to include it in the addressing
    4197             : /// mode. KnownLive1 and KnownLive2 are two values that we know are live at the
    4198             : /// instruction already.
    4199           0 : bool AddressingModeMatcher::valueAlreadyLiveAtInst(Value *Val,Value *KnownLive1,
    4200             :                                                    Value *KnownLive2) {
    4201             :   // If Val is either of the known-live values, we know it is live!
    4202           0 :   if (Val == nullptr || Val == KnownLive1 || Val == KnownLive2)
    4203           0 :     return true;
    4204             : 
    4205             :   // All values other than instructions and arguments (e.g. constants) are live.
    4206           0 :   if (!isa<Instruction>(Val) && !isa<Argument>(Val)) return true;
    4207             : 
    4208             :   // If Val is a constant sized alloca in the entry block, it is live, this is
    4209             :   // true because it is just a reference to the stack/frame pointer, which is
    4210             :   // live for the whole function.
    4211             :   if (AllocaInst *AI = dyn_cast<AllocaInst>(Val))
    4212           0 :     if (AI->isStaticAlloca())
    4213           0 :       return true;
    4214             : 
    4215             :   // Check to see if this value is already used in the memory instruction's
    4216             :   // block.  If so, it's already live into the block at the very least, so we
    4217             :   // can reasonably fold it.
    4218           0 :   return Val->isUsedInBasicBlock(MemoryInst->getParent());
    4219             : }
    4220             : 
    4221             : /// It is possible for the addressing mode of the machine to fold the specified
    4222             : /// instruction into a load or store that ultimately uses it.
    4223             : /// However, the specified instruction has multiple uses.
    4224             : /// Given this, it may actually increase register pressure to fold it
    4225             : /// into the load. For example, consider this code:
    4226             : ///
    4227             : ///     X = ...
    4228             : ///     Y = X+1
    4229             : ///     use(Y)   -> nonload/store
    4230             : ///     Z = Y+1
    4231             : ///     load Z
    4232             : ///
    4233             : /// In this case, Y has multiple uses, and can be folded into the load of Z
    4234             : /// (yielding load [X+2]).  However, doing this will cause both "X" and "X+1" to
    4235             : /// be live at the use(Y) line.  If we don't fold Y into load Z, we use one
    4236             : /// fewer register.  Since Y can't be folded into "use(Y)" we don't increase the
    4237             : /// number of computations either.
    4238             : ///
    4239             : /// Note that this (like most of CodeGenPrepare) is just a rough heuristic.  If
    4240             : /// X was live across 'load Z' for other reasons, we actually *would* want to
    4241             : /// fold the addressing mode in the Z case.  This would make Y die earlier.
    4242           0 : bool AddressingModeMatcher::
    4243             : isProfitableToFoldIntoAddressingMode(Instruction *I, ExtAddrMode &AMBefore,
    4244             :                                      ExtAddrMode &AMAfter) {
    4245           0 :   if (IgnoreProfitability) return true;
    4246             : 
    4247             :   // AMBefore is the addressing mode before this instruction was folded into it,
    4248             :   // and AMAfter is the addressing mode after the instruction was folded.  Get
    4249             :   // the set of registers referenced by AMAfter and subtract out those
    4250             :   // referenced by AMBefore: this is the set of values which folding in this
    4251             :   // address extends the lifetime of.
    4252             :   //
    4253             :   // Note that there are only two potential values being referenced here,
    4254             :   // BaseReg and ScaleReg (global addresses are always available, as are any
    4255             :   // folded immediates).
    4256           0 :   Value *BaseReg = AMAfter.BaseReg, *ScaledReg = AMAfter.ScaledReg;
    4257             : 
    4258             :   // If the BaseReg or ScaledReg was referenced by the previous addrmode, their
    4259             :   // lifetime wasn't extended by adding this instruction.
    4260           0 :   if (valueAlreadyLiveAtInst(BaseReg, AMBefore.BaseReg, AMBefore.ScaledReg))
    4261             :     BaseReg = nullptr;
    4262           0 :   if (valueAlreadyLiveAtInst(ScaledReg, AMBefore.BaseReg, AMBefore.ScaledReg))
    4263             :     ScaledReg = nullptr;
    4264             : 
    4265             :   // If folding this instruction (and it's subexprs) didn't extend any live
    4266             :   // ranges, we're ok with it.
    4267           0 :   if (!BaseReg && !ScaledReg)
    4268           0 :     return true;
    4269             : 
    4270             :   // If all uses of this instruction can have the address mode sunk into them,
    4271             :   // we can remove the addressing mode and effectively trade one live register
    4272             :   // for another (at worst.)  In this context, folding an addressing mode into
    4273             :   // the use is just a particularly nice way of sinking it.
    4274             :   SmallVector<std::pair<Instruction*,unsigned>, 16> MemoryUses;
    4275             :   SmallPtrSet<Instruction*, 16> ConsideredInsts;
    4276           0 :   if (FindAllMemoryUses(I, MemoryUses, ConsideredInsts, TLI, TRI))
    4277           0 :     return false;  // Has a non-memory, non-foldable use!
    4278             : 
    4279             :   // Now that we know that all uses of this instruction are part of a chain of
    4280             :   // computation involving only operations that could theoretically be folded
    4281             :   // into a memory use, loop over each of these memory operation uses and see
    4282             :   // if they could  *actually* fold the instruction.  The assumption is that
    4283             :   // addressing modes are cheap and that duplicating the computation involved
    4284             :   // many times is worthwhile, even on a fastpath. For sinking candidates
    4285             :   // (i.e. cold call sites), this serves as a way to prevent excessive code
    4286             :   // growth since most architectures have some reasonable small and fast way to
    4287             :   // compute an effective address.  (i.e LEA on x86)
    4288             :   SmallVector<Instruction*, 32> MatchedAddrModeInsts;
    4289           0 :   for (unsigned i = 0, e = MemoryUses.size(); i != e; ++i) {
    4290           0 :     Instruction *User = MemoryUses[i].first;
    4291           0 :     unsigned OpNo = MemoryUses[i].second;
    4292             : 
    4293             :     // Get the access type of this use.  If the use isn't a pointer, we don't
    4294             :     // know what it accesses.
    4295           0 :     Value *Address = User->getOperand(OpNo);
    4296           0 :     PointerType *AddrTy = dyn_cast<PointerType>(Address->getType());
    4297             :     if (!AddrTy)
    4298           0 :       return false;
    4299           0 :     Type *AddressAccessTy = AddrTy->getElementType();
    4300             :     unsigned AS = AddrTy->getAddressSpace();
    4301             : 
    4302             :     // Do a match against the root of this address, ignoring profitability. This
    4303             :     // will tell us if the addressing mode for the memory operation will
    4304             :     // *actually* cover the shared instruction.
    4305           0 :     ExtAddrMode Result;
    4306             :     std::pair<AssertingVH<GetElementPtrInst>, int64_t> LargeOffsetGEP(nullptr,
    4307             :                                                                       0);
    4308             :     TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    4309           0 :         TPT.getRestorationPoint();
    4310             :     AddressingModeMatcher Matcher(
    4311             :         MatchedAddrModeInsts, TLI, TRI, AddressAccessTy, AS, MemoryInst, Result,
    4312           0 :         InsertedInsts, PromotedInsts, TPT, LargeOffsetGEP);
    4313           0 :     Matcher.IgnoreProfitability = true;
    4314           0 :     bool Success = Matcher.matchAddr(Address, 0);
    4315             :     (void)Success; assert(Success && "Couldn't select *anything*?");
    4316             : 
    4317             :     // The match was to check the profitability, the changes made are not
    4318             :     // part of the original matcher. Therefore, they should be dropped
    4319             :     // otherwise the original matcher will not present the right state.
    4320           0 :     TPT.rollback(LastKnownGood);
    4321             : 
    4322             :     // If the match didn't cover I, then it won't be shared by it.
    4323           0 :     if (!is_contained(MatchedAddrModeInsts, I))
    4324           0 :       return false;
    4325             : 
    4326             :     MatchedAddrModeInsts.clear();
    4327             :   }
    4328             : 
    4329             :   return true;
    4330             : }
    4331             : 
    4332             : /// Return true if the specified values are defined in a
    4333             : /// different basic block than BB.
    4334             : static bool IsNonLocalValue(Value *V, BasicBlock *BB) {
    4335             :   if (Instruction *I = dyn_cast<Instruction>(V))
    4336           0 :     return I->getParent() != BB;
    4337             :   return false;
    4338             : }
    4339             : 
    4340             : /// Sink addressing mode computation immediate before MemoryInst if doing so
    4341             : /// can be done without increasing register pressure.  The need for the
    4342             : /// register pressure constraint means this can end up being an all or nothing
    4343             : /// decision for all uses of the same addressing computation.
    4344             : ///
    4345             : /// Load and Store Instructions often have addressing modes that can do
    4346             : /// significant amounts of computation. As such, instruction selection will try
    4347             : /// to get the load or store to do as much computation as possible for the
    4348             : /// program. The problem is that isel can only see within a single block. As
    4349             : /// such, we sink as much legal addressing mode work into the block as possible.
    4350             : ///
    4351             : /// This method is used to optimize both load/store and inline asms with memory
    4352             : /// operands.  It's also used to sink addressing computations feeding into cold
    4353             : /// call sites into their (cold) basic block.
    4354             : ///
    4355             : /// The motivation for handling sinking into cold blocks is that doing so can
    4356             : /// both enable other address mode sinking (by satisfying the register pressure
    4357             : /// constraint above), and reduce register pressure globally (by removing the
    4358             : /// addressing mode computation from the fast path entirely.).
    4359     1716614 : bool CodeGenPrepare::optimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
    4360             :                                         Type *AccessTy, unsigned AddrSpace) {
    4361     1716614 :   Value *Repl = Addr;
    4362             : 
    4363             :   // Try to collapse single-value PHI nodes.  This is necessary to undo
    4364             :   // unprofitable PRE transformations.
    4365             :   SmallVector<Value*, 8> worklist;
    4366             :   SmallPtrSet<Value*, 16> Visited;
    4367     1716614 :   worklist.push_back(Addr);
    4368             : 
    4369             :   // Use a worklist to iteratively look through PHI and select nodes, and
    4370             :   // ensure that the addressing mode obtained from the non-PHI/select roots of
    4371             :   // the graph are compatible.
    4372             :   bool PhiOrSelectSeen = false;
    4373             :   SmallVector<Instruction*, 16> AddrModeInsts;
    4374     1716614 :   const SimplifyQuery SQ(*DL, TLInfo);
    4375     1716614 :   AddressingModeCombiner AddrModes(SQ, { Addr, MemoryInst->getParent() });
    4376     1716614 :   TypePromotionTransaction TPT(RemovedInsts);
    4377             :   TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    4378             :       TPT.getRestorationPoint();
    4379     3790014 :   while (!worklist.empty()) {
    4380     2078074 :     Value *V = worklist.back();
    4381             :     worklist.pop_back();
    4382             : 
    4383             :     // We allow traversing cyclic Phi nodes.
    4384             :     // In case of success after this loop we ensure that traversing through
    4385             :     // Phi nodes ends up with all cases to compute address of the form
    4386             :     //    BaseGV + Base + Scale * Index + Offset
    4387             :     // where Scale and Offset are constans and BaseGV, Base and Index
    4388             :     // are exactly the same Values in all cases.
    4389             :     // It means that BaseGV, Scale and Offset dominate our memory instruction
    4390             :     // and have the same value as they had in address computation represented
    4391             :     // as Phi. So we can safely sink address computation to memory instruction.
    4392     2078074 :     if (!Visited.insert(V).second)
    4393      160376 :       continue;
    4394             : 
    4395             :     // For a PHI node, push all of its incoming values.
    4396             :     if (PHINode *P = dyn_cast<PHINode>(V)) {
    4397      518272 :       for (Value *IncValue : P->incoming_values())
    4398      362197 :         worklist.push_back(IncValue);
    4399             :       PhiOrSelectSeen = true;
    4400      156075 :       continue;
    4401             :     }
    4402             :     // Similar for select.
    4403             :     if (SelectInst *SI = dyn_cast<SelectInst>(V)) {
    4404         737 :       worklist.push_back(SI->getFalseValue());
    4405         737 :       worklist.push_back(SI->getTrueValue());
    4406             :       PhiOrSelectSeen = true;
    4407         737 :       continue;
    4408             :     }
    4409             : 
    4410             :     // For non-PHIs, determine the addressing mode being computed.  Note that
    4411             :     // the result may differ depending on what other uses our candidate
    4412             :     // addressing instructions might have.
    4413             :     AddrModeInsts.clear();
    4414             :     std::pair<AssertingVH<GetElementPtrInst>, int64_t> LargeOffsetGEP(nullptr,
    4415             :                                                                       0);
    4416             :     ExtAddrMode NewAddrMode = AddressingModeMatcher::Match(
    4417     1917698 :         V, AccessTy, AddrSpace, MemoryInst, AddrModeInsts, *TLI, *TRI,
    4418     1917698 :         InsertedInsts, PromotedInsts, TPT, LargeOffsetGEP);
    4419             : 
    4420             :     GetElementPtrInst *GEP = LargeOffsetGEP.first;
    4421     1917722 :     if (GEP && GEP->getParent() != MemoryInst->getParent() &&
    4422     1917746 :         !NewGEPBases.count(GEP)) {
    4423             :       // If splitting the underlying data structure can reduce the offset of a
    4424             :       // GEP, collect the GEP.  Skip the GEPs that are the new bases of
    4425             :       // previously split data structures.
    4426          24 :       LargeOffsetGEPMap[GEP->getPointerOperand()].push_back(LargeOffsetGEP);
    4427          48 :       if (LargeOffsetGEPID.find(GEP) == LargeOffsetGEPID.end())
    4428          24 :         LargeOffsetGEPID[GEP] = LargeOffsetGEPID.size();
    4429             :     }
    4430             : 
    4431     1917698 :     NewAddrMode.OriginalValue = V;
    4432     1917698 :     if (!AddrModes.addNewAddrMode(NewAddrMode))
    4433             :       break;
    4434             :   }
    4435             : 
    4436             :   // Try to combine the AddrModes we've collected. If we couldn't collect any,
    4437             :   // or we have multiple but either couldn't combine them or combining them
    4438             :   // wouldn't do anything useful, bail out now.
    4439     1716614 :   if (!AddrModes.combineAddrModes()) {
    4440      154204 :     TPT.rollback(LastKnownGood);
    4441      154204 :     return false;
    4442             :   }
    4443             :   TPT.commit();
    4444             : 
    4445             :   // Get the combined AddrMode (or the only AddrMode, if we only had one).
    4446     1562410 :   ExtAddrMode AddrMode = AddrModes.getAddrMode();
    4447             : 
    4448             :   // If all the instructions matched are already in this BB, don't do anything.
    4449             :   // If we saw a Phi node then it is not local definitely, and if we saw a select
    4450             :   // then we want to push the address calculation past it even if it's already
    4451             :   // in this BB.
    4452     1562410 :   if (!PhiOrSelectSeen && none_of(AddrModeInsts, [&](Value *V) {
    4453           0 :         return IsNonLocalValue(V, MemoryInst->getParent());
    4454             :                   })) {
    4455             :     LLVM_DEBUG(dbgs() << "CGP: Found      local addrmode: " << AddrMode
    4456             :                       << "\n");
    4457             :     return false;
    4458             :   }
    4459             : 
    4460             :   // Insert this computation right after this user.  Since our caller is
    4461             :   // scanning from the top of the BB to the bottom, reuse of the expr are
    4462             :   // guaranteed to happen later.
    4463       14487 :   IRBuilder<> Builder(MemoryInst);
    4464             : 
    4465             :   // Now that we determined the addressing expression we want to use and know
    4466             :   // that we have to sink it into this block.  Check to see if we have already
    4467             :   // done this for some other load/store instr in this block.  If so, reuse
    4468             :   // the computation.  Before attempting reuse, check if the address is valid
    4469             :   // as it may have been erased.
    4470             : 
    4471       14487 :   WeakTrackingVH SunkAddrVH = SunkAddrs[Addr];
    4472             : 
    4473       14487 :   Value * SunkAddr = SunkAddrVH.pointsToAliveValue() ? SunkAddrVH : nullptr;
    4474       14487 :   if (SunkAddr) {
    4475             :     LLVM_DEBUG(dbgs() << "CGP: Reusing nonlocal addrmode: " << AddrMode
    4476             :                       << " for " << *MemoryInst << "\n");
    4477        1139 :     if (SunkAddr->getType() != Addr->getType())
    4478           0 :       SunkAddr = Builder.CreatePointerCast(SunkAddr, Addr->getType());
    4479       13348 :   } else if (AddrSinkUsingGEPs ||
    4480           5 :              (!AddrSinkUsingGEPs.getNumOccurrences() && TM && TTI->useAA())) {
    4481             :     // By default, we use the GEP-based method when AA is used later. This
    4482             :     // prevents new inttoptr/ptrtoint pairs from degrading AA capabilities.
    4483             :     LLVM_DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode
    4484             :                       << " for " << *MemoryInst << "\n");
    4485       13343 :     Type *IntPtrTy = DL->getIntPtrType(Addr->getType());
    4486             :     Value *ResultPtr = nullptr, *ResultIndex = nullptr;
    4487             : 
    4488             :     // First, find the pointer.
    4489       13343 :     if (AddrMode.BaseReg && AddrMode.BaseReg->getType()->isPointerTy()) {
    4490             :       ResultPtr = AddrMode.BaseReg;
    4491             :       AddrMode.BaseReg = nullptr;
    4492             :     }
    4493             : 
    4494       13343 :     if (AddrMode.Scale && AddrMode.ScaledReg->getType()->isPointerTy()) {
    4495             :       // We can't add more than one pointer together, nor can we scale a
    4496             :       // pointer (both of which seem meaningless).
    4497           0 :       if (ResultPtr || AddrMode.Scale != 1)
    4498             :         return false;
    4499             : 
    4500             :       ResultPtr = AddrMode.ScaledReg;
    4501             :       AddrMode.Scale = 0;
    4502             :     }
    4503             : 
    4504             :     // It is only safe to sign extend the BaseReg if we know that the math
    4505             :     // required to create it did not overflow before we extend it. Since
    4506             :     // the original IR value was tossed in favor of a constant back when
    4507             :     // the AddrMode was created we need to bail out gracefully if widths
    4508             :     // do not match instead of extending it.
    4509             :     //
    4510             :     // (See below for code to add the scale.)
    4511       13343 :     if (AddrMode.Scale) {
    4512        2190 :       Type *ScaledRegTy = AddrMode.ScaledReg->getType();
    4513        2190 :       if (cast<IntegerType>(IntPtrTy)->getBitWidth() >
    4514             :           cast<IntegerType>(ScaledRegTy)->getBitWidth())
    4515             :         return false;
    4516             :     }
    4517             : 
    4518       13333 :     if (AddrMode.BaseGV) {
    4519           4 :       if (ResultPtr)
    4520             :         return false;
    4521             : 
    4522             :       ResultPtr = AddrMode.BaseGV;
    4523             :     }
    4524             : 
    4525             :     // If the real base value actually came from an inttoptr, then the matcher
    4526             :     // will look through it and provide only the integer value. In that case,
    4527             :     // use it here.
    4528       13333 :     if (!DL->isNonIntegralPointerType(Addr->getType())) {
    4529       13330 :       if (!ResultPtr && AddrMode.BaseReg) {
    4530         295 :         ResultPtr = Builder.CreateIntToPtr(AddrMode.BaseReg, Addr->getType(),
    4531             :                                            "sunkaddr");
    4532         295 :         AddrMode.BaseReg = nullptr;
    4533       13035 :       } else if (!ResultPtr && AddrMode.Scale == 1) {
    4534           0 :         ResultPtr = Builder.CreateIntToPtr(AddrMode.ScaledReg, Addr->getType(),
    4535             :                                            "sunkaddr");
    4536             :         AddrMode.Scale = 0;
    4537             :       }
    4538             :     }
    4539             : 
    4540       13333 :     if (!ResultPtr &&
    4541           9 :         !AddrMode.BaseReg && !AddrMode.Scale && !AddrMode.BaseOffs) {
    4542           3 :       SunkAddr = Constant::getNullValue(Addr->getType());
    4543       13330 :     } else if (!ResultPtr) {
    4544             :       return false;
    4545             :     } else {
    4546             :       Type *I8PtrTy =
    4547       13322 :           Builder.getInt8PtrTy(Addr->getType()->getPointerAddressSpace());
    4548       13322 :       Type *I8Ty = Builder.getInt8Ty();
    4549             : 
    4550             :       // Start with the base register. Do this first so that subsequent address
    4551             :       // matching finds it last, which will prevent it from trying to match it
    4552             :       // as the scaled value in case it happens to be a mul. That would be
    4553             :       // problematic if we've sunk a different mul for the scale, because then
    4554             :       // we'd end up sinking both muls.
    4555       13322 :       if (AddrMode.BaseReg) {
    4556             :         Value *V = AddrMode.BaseReg;
    4557           2 :         if (V->getType() != IntPtrTy)
    4558           2 :           V = Builder.CreateIntCast(V, IntPtrTy, /*isSigned=*/true, "sunkaddr");
    4559             : 
    4560             :         ResultIndex = V;
    4561             :       }
    4562             : 
    4563             :       // Add the scale value.
    4564       13322 :       if (AddrMode.Scale) {
    4565             :         Value *V = AddrMode.ScaledReg;
    4566        2180 :         if (V->getType() == IntPtrTy) {
    4567             :           // done.
    4568             :         } else {
    4569             :           assert(cast<IntegerType>(IntPtrTy)->getBitWidth() <
    4570             :                  cast<IntegerType>(V->getType())->getBitWidth() &&
    4571             :                  "We can't transform if ScaledReg is too narrow");
    4572           1 :           V = Builder.CreateTrunc(V, IntPtrTy, "sunkaddr");
    4573             :         }
    4574             : 
    4575        2180 :         if (AddrMode.Scale != 1)
    4576        1185 :           V = Builder.CreateMul(V, ConstantInt::get(IntPtrTy, AddrMode.Scale),
    4577             :                                 "sunkaddr");
    4578        2180 :         if (ResultIndex)
    4579           0 :           ResultIndex = Builder.CreateAdd(ResultIndex, V, "sunkaddr");
    4580             :         else
    4581             :           ResultIndex = V;
    4582             :       }
    4583             : 
    4584             :       // Add in the Base Offset if present.
    4585       13322 :       if (AddrMode.BaseOffs) {
    4586       12253 :         Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs);
    4587       12253 :         if (ResultIndex) {
    4588             :           // We need to add this separately from the scale above to help with
    4589             :           // SDAG consecutive load/store merging.
    4590        1663 :           if (ResultPtr->getType() != I8PtrTy)
    4591        1080 :             ResultPtr = Builder.CreatePointerCast(ResultPtr, I8PtrTy);
    4592        1663 :           ResultPtr = Builder.CreateGEP(I8Ty, ResultPtr, ResultIndex, "sunkaddr");
    4593             :         }
    4594             : 
    4595             :         ResultIndex = V;
    4596             :       }
    4597             : 
    4598       13322 :       if (!ResultIndex) {
    4599             :         SunkAddr = ResultPtr;
    4600             :       } else {
    4601       12772 :         if (ResultPtr->getType() != I8PtrTy)
    4602       10569 :           ResultPtr = Builder.CreatePointerCast(ResultPtr, I8PtrTy);
    4603       12772 :         SunkAddr = Builder.CreateGEP(I8Ty, ResultPtr, ResultIndex, "sunkaddr");
    4604             :       }
    4605             : 
    4606       13322 :       if (SunkAddr->getType() != Addr->getType())
    4607       11934 :         SunkAddr = Builder.CreatePointerCast(SunkAddr, Addr->getType());
    4608             :     }
    4609             :   } else {
    4610             :     // We'd require a ptrtoint/inttoptr down the line, which we can't do for
    4611             :     // non-integral pointers, so in that case bail out now.
    4612           5 :     Type *BaseTy = AddrMode.BaseReg ? AddrMode.BaseReg->getType() : nullptr;
    4613           5 :     Type *ScaleTy = AddrMode.Scale ? AddrMode.ScaledReg->getType() : nullptr;
    4614             :     PointerType *BasePtrTy = dyn_cast_or_null<PointerType>(BaseTy);
    4615             :     PointerType *ScalePtrTy = dyn_cast_or_null<PointerType>(ScaleTy);
    4616           6 :     if (DL->isNonIntegralPointerType(Addr->getType()) ||
    4617           1 :         (BasePtrTy && DL->isNonIntegralPointerType(BasePtrTy)) ||
    4618           0 :         (ScalePtrTy && DL->isNonIntegralPointerType(ScalePtrTy)) ||
    4619           0 :         (AddrMode.BaseGV &&
    4620           0 :          DL->isNonIntegralPointerType(AddrMode.BaseGV->getType())))
    4621           5 :       return false;
    4622             : 
    4623             :     LLVM_DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode
    4624             :                       << " for " << *MemoryInst << "\n");
    4625           0 :     Type *IntPtrTy = DL->getIntPtrType(Addr->getType());
    4626             :     Value *Result = nullptr;
    4627             : 
    4628             :     // Start with the base register. Do this first so that subsequent address
    4629             :     // matching finds it last, which will prevent it from trying to match it
    4630             :     // as the scaled value in case it happens to be a mul. That would be
    4631             :     // problematic if we've sunk a different mul for the scale, because then
    4632             :     // we'd end up sinking both muls.
    4633           0 :     if (AddrMode.BaseReg) {
    4634             :       Value *V = AddrMode.BaseReg;
    4635           0 :       if (V->getType()->isPointerTy())
    4636           0 :         V = Builder.CreatePtrToInt(V, IntPtrTy, "sunkaddr");
    4637           0 :       if (V->getType() != IntPtrTy)
    4638           0 :         V = Builder.CreateIntCast(V, IntPtrTy, /*isSigned=*/true, "sunkaddr");
    4639             :       Result = V;
    4640             :     }
    4641             : 
    4642             :     // Add the scale value.
    4643           0 :     if (AddrMode.Scale) {
    4644             :       Value *V = AddrMode.ScaledReg;
    4645           0 :       if (V->getType() == IntPtrTy) {
    4646             :         // done.
    4647           0 :       } else if (V->getType()->isPointerTy()) {
    4648           0 :         V = Builder.CreatePtrToInt(V, IntPtrTy, "sunkaddr");
    4649           0 :       } else if (cast<IntegerType>(IntPtrTy)->getBitWidth() <
    4650             :                  cast<IntegerType>(V->getType())->getBitWidth()) {
    4651           0 :         V = Builder.CreateTrunc(V, IntPtrTy, "sunkaddr");
    4652             :       } else {
    4653             :         // It is only safe to sign extend the BaseReg if we know that the math
    4654             :         // required to create it did not overflow before we extend it. Since
    4655             :         // the original IR value was tossed in favor of a constant back when
    4656             :         // the AddrMode was created we need to bail out gracefully if widths
    4657             :         // do not match instead of extending it.
    4658             :         Instruction *I = dyn_cast_or_null<Instruction>(Result);
    4659           0 :         if (I && (Result != AddrMode.BaseReg))
    4660           0 :           I->eraseFromParent();
    4661           0 :         return false;
    4662             :       }
    4663           0 :       if (AddrMode.Scale != 1)
    4664           0 :         V = Builder.CreateMul(V, ConstantInt::get(IntPtrTy, AddrMode.Scale),
    4665             :                               "sunkaddr");
    4666           0 :       if (Result)
    4667           0 :         Result = Builder.CreateAdd(Result, V, "sunkaddr");
    4668             :       else
    4669             :         Result = V;
    4670             :     }
    4671             : 
    4672             :     // Add in the BaseGV if present.
    4673           0 :     if (AddrMode.BaseGV) {
    4674           0 :       Value *V = Builder.CreatePtrToInt(AddrMode.BaseGV, IntPtrTy, "sunkaddr");
    4675           0 :       if (Result)
    4676           0 :         Result = Builder.CreateAdd(Result, V, "sunkaddr");
    4677             :       else
    4678             :         Result = V;
    4679             :     }
    4680             : 
    4681             :     // Add in the Base Offset if present.
    4682           0 :     if (AddrMode.BaseOffs) {
    4683           0 :       Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs);
    4684           0 :       if (Result)
    4685           0 :         Result = Builder.CreateAdd(Result, V, "sunkaddr");
    4686             :       else
    4687             :         Result = V;
    4688             :     }
    4689             : 
    4690           0 :     if (!Result)
    4691           0 :       SunkAddr = Constant::getNullValue(Addr->getType());
    4692             :     else
    4693           0 :       SunkAddr = Builder.CreateIntToPtr(Result, Addr->getType(), "sunkaddr");
    4694             :   }
    4695             : 
    4696       14464 :   MemoryInst->replaceUsesOfWith(Repl, SunkAddr);
    4697             :   // Store the newly computed address into the cache. In the case we reused a
    4698             :   // value, this should be idempotent.
    4699       14464 :   SunkAddrs[Addr] = WeakTrackingVH(SunkAddr);
    4700             : 
    4701             :   // If we have no uses, recursively delete the value and all dead instructions
    4702             :   // using it.
    4703       14464 :   if (Repl->use_empty()) {
    4704             :     // This can cause recursive deletion, which can invalidate our iterator.
    4705             :     // Use a WeakTrackingVH to hold onto it in case this happens.
    4706        6817 :     Value *CurValue = &*CurInstIterator;
    4707             :     WeakTrackingVH IterHandle(CurValue);
    4708        6817 :     BasicBlock *BB = CurInstIterator->getParent();
    4709             : 
    4710        6817 :     RecursivelyDeleteTriviallyDeadInstructions(Repl, TLInfo);
    4711             : 
    4712        6817 :     if (IterHandle != CurValue) {
    4713             :       // If the iterator instruction was recursively deleted, start over at the
    4714             :       // start of the block.
    4715           1 :       CurInstIterator = BB->begin();
    4716             :       SunkAddrs.clear();
    4717             :     }
    4718             :   }
    4719             :   ++NumMemoryInsts;
    4720             :   return true;
    4721             : }
    4722             : 
    4723             : /// If there are any memory operands, use OptimizeMemoryInst to sink their
    4724             : /// address computing into the block when possible / profitable.
    4725       14103 : bool CodeGenPrepare::optimizeInlineAsmInst(CallInst *CS) {
    4726             :   bool MadeChange = false;
    4727             : 
    4728             :   const TargetRegisterInfo *TRI =
    4729       14103 :       TM->getSubtargetImpl(*CS->getFunction())->getRegisterInfo();
    4730             :   TargetLowering::AsmOperandInfoVector TargetConstraints =
    4731       42309 :       TLI->ParseConstraints(*DL, TRI, CS);
    4732             :   unsigned ArgNo = 0;
    4733       94571 :   for (unsigned i = 0, e = TargetConstraints.size(); i != e; ++i) {
    4734       66365 :     TargetLowering::AsmOperandInfo &OpInfo = TargetConstraints[i];
    4735             : 
    4736             :     // Compute the constraint code and ConstraintType to use.
    4737       66365 :     TLI->ComputeConstraintToUse(OpInfo, SDValue());
    4738             : 
    4739       66365 :     if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
    4740        4002 :         OpInfo.isIndirect) {
    4741        3099 :       Value *OpVal = CS->getArgOperand(ArgNo++);
    4742        3099 :       MadeChange |= optimizeMemoryInst(CS, OpVal, OpVal->getType(), ~0u);
    4743       63266 :     } else if (OpInfo.Type == InlineAsm::isInput)
    4744        8256 :       ArgNo++;
    4745             :   }
    4746             : 
    4747       14103 :   return MadeChange;
    4748             : }
    4749             : 
    4750             : /// Check if all the uses of \p Val are equivalent (or free) zero or
    4751             : /// sign extensions.
    4752          38 : static bool hasSameExtUse(Value *Val, const TargetLowering &TLI) {
    4753             :   assert(!Val->use_empty() && "Input must have at least one use");
    4754             :   const Instruction *FirstUser = cast<Instruction>(*Val->user_begin());
    4755             :   bool IsSExt = isa<SExtInst>(FirstUser);
    4756          38 :   Type *ExtTy = FirstUser->getType();
    4757          99 :   for (const User *U : Val->users()) {
    4758             :     const Instruction *UI = cast<Instruction>(U);
    4759          85 :     if ((IsSExt && !isa<SExtInst>(UI)) || (!IsSExt && !isa<ZExtInst>(UI)))
    4760             :       return false;
    4761          66 :     Type *CurTy = UI->getType();
    4762             :     // Same input and output types: Same instruction after CSE.
    4763          66 :     if (CurTy == ExtTy)
    4764             :       continue;
    4765             : 
    4766             :     // If IsSExt is true, we are in this situation:
    4767             :     // a = Val
    4768             :     // b = sext ty1 a to ty2
    4769             :     // c = sext ty1 a to ty3
    4770             :     // Assuming ty2 is shorter than ty3, this could be turned into:
    4771             :     // a = Val
    4772             :     // b = sext ty1 a to ty2
    4773             :     // c = sext ty2 b to ty3
    4774             :     // However, the last sext is not free.
    4775          14 :     if (IsSExt)
    4776             :       return false;
    4777             : 
    4778             :     // This is a ZExt, maybe this is free to extend from one type to another.
    4779             :     // In that case, we would not account for a different use.
    4780             :     Type *NarrowTy;
    4781             :     Type *LargeTy;
    4782          13 :     if (ExtTy->getScalarType()->getIntegerBitWidth() >
    4783             :         CurTy->getScalarType()->getIntegerBitWidth()) {
    4784             :       NarrowTy = CurTy;
    4785             :       LargeTy = ExtTy;
    4786             :     } else {
    4787             :       NarrowTy = ExtTy;
    4788             :       LargeTy = CurTy;
    4789             :     }
    4790             : 
    4791          13 :     if (!TLI.isZExtFree(NarrowTy, LargeTy))
    4792             :       return false;
    4793             :   }
    4794             :   // All uses are the same or can be derived from one another for free.
    4795             :   return true;
    4796             : }
    4797             : 
    4798             : /// Try to speculatively promote extensions in \p Exts and continue
    4799             : /// promoting through newly promoted operands recursively as far as doing so is
    4800             : /// profitable. Save extensions profitably moved up, in \p ProfitablyMovedExts.
    4801             : /// When some promotion happened, \p TPT contains the proper state to revert
    4802             : /// them.
    4803             : ///
    4804             : /// \return true if some promotion happened, false otherwise.
    4805       44509 : bool CodeGenPrepare::tryToPromoteExts(
    4806             :     TypePromotionTransaction &TPT, const SmallVectorImpl<Instruction *> &Exts,
    4807             :     SmallVectorImpl<Instruction *> &ProfitablyMovedExts,
    4808             :     unsigned CreatedInstsCost) {
    4809             :   bool Promoted = false;
    4810             : 
    4811             :   // Iterate over all the extensions to try to promote them.
    4812       75678 :   for (auto I : Exts) {
    4813             :     // Early check if we directly have ext(load).
    4814       44769 :     if (isa<LoadInst>(I->getOperand(0))) {
    4815       13860 :       ProfitablyMovedExts.push_back(I);
    4816       29037 :       continue;
    4817             :     }
    4818             : 
    4819             :     // Check whether or not we want to do any promotion.  The reason we have
    4820             :     // this check inside the for loop is to catch the case where an extension
    4821             :     // is directly fed by a load because in such case the extension can be moved
    4822             :     // up without any promotion on its operands.
    4823       30909 :     if (!TLI || !TLI->enableExtLdPromotion() || DisableExtLdPromotion)
    4824       13600 :       return false;
    4825             : 
    4826             :     // Get the action to perform the promotion.
    4827             :     TypePromotionHelper::Action TPH =
    4828       17309 :         TypePromotionHelper::getAction(I, InsertedInsts, *TLI, PromotedInsts);
    4829             :     // Check if we can promote.
    4830       17309 :     if (!TPH) {
    4831             :       // Save the current extension as we cannot move up through its operand.
    4832       15108 :       ProfitablyMovedExts.push_back(I);
    4833       15108 :       continue;
    4834             :     }
    4835             : 
    4836             :     // Save the current state.
    4837             :     TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    4838             :         TPT.getRestorationPoint();
    4839             :     SmallVector<Instruction *, 4> NewExts;
    4840        2201 :     unsigned NewCreatedInstsCost = 0;
    4841        2201 :     unsigned ExtCost = !TLI->isExtFree(I);
    4842             :     // Promote.
    4843        2201 :     Value *PromotedVal = TPH(I, TPT, PromotedInsts, NewCreatedInstsCost,
    4844        2201 :                              &NewExts, nullptr, *TLI);
    4845             :     assert(PromotedVal &&
    4846             :            "TypePromotionHelper should have filtered out those cases");
    4847             : 
    4848             :     // We would be able to merge only one extension in a load.
    4849             :     // Therefore, if we have more than 1 new extension we heuristically
    4850             :     // cut this search path, because it means we degrade the code quality.
    4851             :     // With exactly 2, the transformation is neutral, because we will merge
    4852             :     // one extension but leave one. However, we optimistically keep going,
    4853             :     // because the new extension may be removed too.
    4854        2201 :     long long TotalCreatedInstsCost = CreatedInstsCost + NewCreatedInstsCost;
    4855             :     // FIXME: It would be possible to propagate a negative value instead of
    4856             :     // conservatively ceiling it to 0.
    4857        2201 :     TotalCreatedInstsCost =
    4858        2532 :         std::max((long long)0, (TotalCreatedInstsCost - ExtCost));
    4859        2201 :     if (!StressExtLdPromotion &&
    4860        2114 :         (TotalCreatedInstsCost > 1 ||
    4861        2114 :          !isPromotedInstructionLegal(*TLI, *DL, PromotedVal))) {
    4862             :       // This promotion is not profitable, rollback to the previous state, and
    4863             :       // save the current extension in ProfitablyMovedExts as the latest
    4864             :       // speculative promotion turned out to be unprofitable.
    4865          31 :       TPT.rollback(LastKnownGood);
    4866          31 :       ProfitablyMovedExts.push_back(I);
    4867          31 :       continue;
    4868             :     }
    4869             :     // Continue promoting NewExts as far as doing so is profitable.
    4870             :     SmallVector<Instruction *, 2> NewlyMovedExts;
    4871        2170 :     (void)tryToPromoteExts(TPT, NewExts, NewlyMovedExts, TotalCreatedInstsCost);
    4872             :     bool NewPromoted = false;
    4873        4663 :     for (auto ExtInst : NewlyMovedExts) {
    4874        2493 :       Instruction *MovedExt = cast<Instruction>(ExtInst);
    4875        2493 :       Value *ExtOperand = MovedExt->getOperand(0);
    4876             :       // If we have reached to a load, we need this extra profitability check
    4877             :       // as it could potentially be merged into an ext(load).
    4878        1323 :       if (isa<LoadInst>(ExtOperand) &&
    4879        1366 :           !(StressExtLdPromotion || NewCreatedInstsCost <= ExtCost ||
    4880          38 :             (ExtOperand->hasOneUse() || hasSameExtUse(ExtOperand, *TLI))))
    4881          24 :         continue;
    4882             : 
    4883        2469 :       ProfitablyMovedExts.push_back(MovedExt);
    4884             :       NewPromoted = true;
    4885             :     }
    4886             : 
    4887             :     // If none of speculative promotions for NewExts is profitable, rollback
    4888             :     // and save the current extension (I) as the last profitable extension.
    4889        2170 :     if (!NewPromoted) {
    4890          38 :       TPT.rollback(LastKnownGood);
    4891          38 :       ProfitablyMovedExts.push_back(I);
    4892             :       continue;
    4893             :     }
    4894             :     // The promotion is profitable.
    4895             :     Promoted = true;
    4896             :   }
    4897       30909 :   return Promoted;
    4898             : }
    4899             : 
    4900             : /// Merging redundant sexts when one is dominating the other.
    4901          36 : bool CodeGenPrepare::mergeSExts(Function &F) {
    4902          36 :   DominatorTree DT(F);
    4903             :   bool Changed = false;
    4904          86 :   for (auto &Entry : ValToSExtendedUses) {
    4905             :     SExts &Insts = Entry.second;
    4906             :     SExts CurPts;
    4907         153 :     for (Instruction *Inst : Insts) {
    4908         103 :       if (RemovedInsts.count(Inst) || !isa<SExtInst>(Inst) ||
    4909         206 :           Inst->getOperand(0) != Entry.first)
    4910             :         continue;
    4911             :       bool inserted = false;
    4912         103 :       for (auto &Pt : CurPts) {
    4913          53 :         if (DT.dominates(Inst, Pt)) {
    4914          30 :           Pt->replaceAllUsesWith(Inst);
    4915          30 :           RemovedInsts.insert(Pt);
    4916          30 :           Pt->removeFromParent();
    4917          30 :           Pt = Inst;
    4918             :           inserted = true;
    4919             :           Changed = true;
    4920          30 :           break;
    4921             :         }
    4922          23 :         if (!DT.dominates(Pt, Inst))
    4923             :           // Give up if we need to merge in a common dominator as the
    4924             :           // experiments show it is not profitable.
    4925             :           continue;
    4926          23 :         Inst->replaceAllUsesWith(Pt);
    4927          23 :         RemovedInsts.insert(Inst);
    4928          23 :         Inst->removeFromParent();
    4929             :         inserted = true;
    4930             :         Changed = true;
    4931          23 :         break;
    4932             :       }
    4933         103 :       if (!inserted)
    4934          50 :         CurPts.push_back(Inst);
    4935             :     }
    4936             :   }
    4937          36 :   return Changed;
    4938             : }
    4939             : 
    4940             : // Spliting large data structures so that the GEPs accessing them can have
    4941             : // smaller offsets so that they can be sunk to the same blocks as their users.
    4942             : // For example, a large struct starting from %base is splitted into two parts
    4943             : // where the second part starts from %new_base.
    4944             : //
    4945             : // Before:
    4946             : // BB0:
    4947             : //   %base     =
    4948             : //
    4949             : // BB1:
    4950             : //   %gep0     = gep %base, off0
    4951             : //   %gep1     = gep %base, off1
    4952             : //   %gep2     = gep %base, off2
    4953             : //
    4954             : // BB2:
    4955             : //   %load1    = load %gep0
    4956             : //   %load2    = load %gep1
    4957             : //   %load3    = load %gep2
    4958             : //
    4959             : // After:
    4960             : // BB0:
    4961             : //   %base     =
    4962             : //   %new_base = gep %base, off0
    4963             : //
    4964             : // BB1:
    4965             : //   %new_gep0 = %new_base
    4966             : //   %new_gep1 = gep %new_base, off1 - off0
    4967             : //   %new_gep2 = gep %new_base, off2 - off0
    4968             : //
    4969             : // BB2:
    4970             : //   %load1    = load i32, i32* %new_gep0
    4971             : //   %load2    = load i32, i32* %new_gep1
    4972             : //   %load3    = load i32, i32* %new_gep2
    4973             : //
    4974             : // %new_gep1 and %new_gep2 can be sunk to BB2 now after the splitting because
    4975             : // their offsets are smaller enough to fit into the addressing mode.
    4976          11 : bool CodeGenPrepare::splitLargeGEPOffsets() {
    4977             :   bool Changed = false;
    4978          23 :   for (auto &Entry : LargeOffsetGEPMap) {
    4979             :     Value *OldBase = Entry.first;
    4980             :     SmallVectorImpl<std::pair<AssertingVH<GetElementPtrInst>, int64_t>>
    4981             :         &LargeOffsetGEPs = Entry.second;
    4982             :     auto compareGEPOffset =
    4983             :         [&](const std::pair<GetElementPtrInst *, int64_t> &LHS,
    4984             :             const std::pair<GetElementPtrInst *, int64_t> &RHS) {
    4985             :           if (LHS.first == RHS.first)
    4986             :             return false;
    4987             :           if (LHS.second != RHS.second)
    4988             :             return LHS.second < RHS.second;
    4989             :           return LargeOffsetGEPID[LHS.first] < LargeOffsetGEPID[RHS.first];
    4990             :         };
    4991             :     // Sorting all the GEPs of the same data structures based on the offsets.
    4992             :     llvm::sort(LargeOffsetGEPs, compareGEPOffset);
    4993             :     LargeOffsetGEPs.erase(
    4994             :         std::unique(LargeOffsetGEPs.begin(), LargeOffsetGEPs.end()),
    4995             :         LargeOffsetGEPs.end());
    4996             :     // Skip if all the GEPs have the same offsets.
    4997          24 :     if (LargeOffsetGEPs.front().second == LargeOffsetGEPs.back().second)
    4998             :       continue;
    4999             :     GetElementPtrInst *BaseGEP = LargeOffsetGEPs.begin()->first;
    5000             :     int64_t BaseOffset = LargeOffsetGEPs.begin()->second;
    5001             :     Value *NewBaseGEP = nullptr;
    5002             : 
    5003             :     auto LargeOffsetGEP = LargeOffsetGEPs.begin();
    5004          36 :     while (LargeOffsetGEP != LargeOffsetGEPs.end()) {
    5005             :       GetElementPtrInst *GEP = LargeOffsetGEP->first;
    5006          24 :       int64_t Offset = LargeOffsetGEP->second;
    5007          24 :       if (Offset != BaseOffset) {
    5008          12 :         TargetLowering::AddrMode AddrMode;
    5009          12 :         AddrMode.BaseOffs = Offset - BaseOffset;
    5010             :         // The result type of the GEP might not be the type of the memory
    5011             :         // access.
    5012          12 :         if (!TLI->isLegalAddressingMode(*DL, AddrMode,
    5013             :                                         GEP->getResultElementType(),
    5014          12 :                                         GEP->getAddressSpace())) {
    5015             :           // We need to create a new base if the offset to the current base is
    5016             :           // too large to fit into the addressing mode. So, a very large struct
    5017             :           // may be splitted into several parts.
    5018             :           BaseGEP = GEP;
    5019             :           BaseOffset = Offset;
    5020             :           NewBaseGEP = nullptr;
    5021             :         }
    5022             :       }
    5023             : 
    5024             :       // Generate a new GEP to replace the current one.
    5025          24 :       IRBuilder<> Builder(GEP);
    5026          24 :       Type *IntPtrTy = DL->getIntPtrType(GEP->getType());
    5027             :       Type *I8PtrTy =
    5028          24 :           Builder.getInt8PtrTy(GEP->getType()->getPointerAddressSpace());
    5029          24 :       Type *I8Ty = Builder.getInt8Ty();
    5030             : 
    5031          24 :       if (!NewBaseGEP) {
    5032             :         // Create a new base if we don't have one yet.  Find the insertion
    5033             :         // pointer for the new base first.
    5034             :         BasicBlock::iterator NewBaseInsertPt;
    5035             :         BasicBlock *NewBaseInsertBB;
    5036             :         if (auto *BaseI = dyn_cast<Instruction>(OldBase)) {
    5037             :           // If the base of the struct is an instruction, the new base will be
    5038             :           // inserted close to it.
    5039           9 :           NewBaseInsertBB = BaseI->getParent();
    5040           9 :           if (isa<PHINode>(BaseI))
    5041           1 :             NewBaseInsertPt = NewBaseInsertBB->getFirstInsertionPt();
    5042             :           else if (InvokeInst *Invoke = dyn_cast<InvokeInst>(BaseI)) {
    5043             :             NewBaseInsertBB =
    5044           1 :                 SplitEdge(NewBaseInsertBB, Invoke->getNormalDest());
    5045           1 :             NewBaseInsertPt = NewBaseInsertBB->getFirstInsertionPt();
    5046             :           } else
    5047          14 :             NewBaseInsertPt = std::next(BaseI->getIterator());
    5048             :         } else {
    5049             :           // If the current base is an argument or global value, the new base
    5050             :           // will be inserted to the entry block.
    5051           3 :           NewBaseInsertBB = &BaseGEP->getFunction()->getEntryBlock();
    5052           3 :           NewBaseInsertPt = NewBaseInsertBB->getFirstInsertionPt();
    5053             :         }
    5054          12 :         IRBuilder<> NewBaseBuilder(NewBaseInsertBB, NewBaseInsertPt);
    5055             :         // Create a new base.
    5056          12 :         Value *BaseIndex = ConstantInt::get(IntPtrTy, BaseOffset);
    5057             :         NewBaseGEP = OldBase;
    5058          12 :         if (NewBaseGEP->getType() != I8PtrTy)
    5059          12 :           NewBaseGEP = NewBaseBuilder.CreatePointerCast(NewBaseGEP, I8PtrTy);
    5060             :         NewBaseGEP =
    5061          12 :             NewBaseBuilder.CreateGEP(I8Ty, NewBaseGEP, BaseIndex, "splitgep");
    5062          24 :         NewGEPBases.insert(NewBaseGEP);
    5063             :       }
    5064             : 
    5065             :       Value *NewGEP = NewBaseGEP;
    5066          24 :       if (Offset == BaseOffset) {
    5067          12 :         if (GEP->getType() != I8PtrTy)
    5068          12 :           NewGEP = Builder.CreatePointerCast(NewGEP, GEP->getType());
    5069             :       } else {
    5070             :         // Calculate the new offset for the new GEP.
    5071          12 :         Value *Index = ConstantInt::get(IntPtrTy, Offset - BaseOffset);
    5072          12 :         NewGEP = Builder.CreateGEP(I8Ty, NewBaseGEP, Index);
    5073             : 
    5074          12 :         if (GEP->getType() != I8PtrTy)
    5075          12 :           NewGEP = Builder.CreatePointerCast(NewGEP, GEP->getType());
    5076             :       }
    5077          24 :       GEP->replaceAllUsesWith(NewGEP);
    5078          48 :       LargeOffsetGEPID.erase(GEP);
    5079             :       LargeOffsetGEP = LargeOffsetGEPs.erase(LargeOffsetGEP);
    5080          24 :       GEP->eraseFromParent();
    5081             :       Changed = true;
    5082             :     }
    5083             :   }
    5084          11 :   return Changed;
    5085             : }
    5086             : 
    5087             : /// Return true, if an ext(load) can be formed from an extension in
    5088             : /// \p MovedExts.
    5089       42309 : bool CodeGenPrepare::canFormExtLd(
    5090             :     const SmallVectorImpl<Instruction *> &MovedExts, LoadInst *&LI,
    5091             :     Instruction *&Inst, bool HasPromoted) {
    5092       57411 :   for (auto *MovedExtInst : MovedExts) {
    5093       28860 :     if (isa<LoadInst>(MovedExtInst->getOperand(0))) {
    5094       13758 :       LI = cast<LoadInst>(MovedExtInst->getOperand(0));
    5095       13758 :       Inst = MovedExtInst;
    5096       13758 :       break;
    5097             :     }
    5098             :   }
    5099       42309 :   if (!LI)
    5100             :     return false;
    5101             : 
    5102             :   // If they're already in the same block, there's nothing to do.
    5103             :   // Make the cheap checks first if we did not promote.
    5104             :   // If we promoted, we need to check if it is indeed profitable.
    5105       13758 :   if (!HasPromoted && LI->getParent() == Inst->getParent())
    5106             :     return false;
    5107             : 
    5108        1380 :   return TLI->isExtLoad(LI, Inst, *DL);
    5109             : }
    5110             : 
    5111             : /// Move a zext or sext fed by a load into the same basic block as the load,
    5112             : /// unless conditions are unfavorable. This allows SelectionDAG to fold the
    5113             : /// extend into the load.
    5114             : ///
    5115             : /// E.g.,
    5116             : /// \code
    5117             : /// %ld = load i32* %addr
    5118             : /// %add = add nuw i32 %ld, 4
    5119             : /// %zext = zext i32 %add to i64
    5120             : // \endcode
    5121             : /// =>
    5122             : /// \code
    5123             : /// %ld = load i32* %addr
    5124             : /// %zext = zext i32 %ld to i64
    5125             : /// %add = add nuw i64 %zext, 4
    5126             : /// \encode
    5127             : /// Note that the promotion in %add to i64 is done in tryToPromoteExts(), which
    5128             : /// allow us to match zext(load i32*) to i64.
    5129             : ///
    5130             : /// Also, try to promote the computations used to obtain a sign extended
    5131             : /// value used into memory accesses.
    5132             : /// E.g.,
    5133             : /// \code
    5134             : /// a = add nsw i32 b, 3
    5135             : /// d = sext i32 a to i64
    5136             : /// e = getelementptr ..., i64 d
    5137             : /// \endcode
    5138             : /// =>
    5139             : /// \code
    5140             : /// f = sext i32 b to i64
    5141             : /// a = add nsw i64 f, 3
    5142             : /// e = getelementptr ..., i64 a
    5143             : /// \endcode
    5144             : ///
    5145             : /// \p Inst[in/out] the extension may be modified during the process if some
    5146             : /// promotions apply.
    5147       42311 : bool CodeGenPrepare::optimizeExt(Instruction *&Inst) {
    5148             :   // ExtLoad formation and address type promotion infrastructure requires TLI to
    5149             :   // be effective.
    5150       42311 :   if (!TLI)
    5151             :     return false;
    5152             : 
    5153       42309 :   bool AllowPromotionWithoutCommonHeader = false;
    5154             :   /// See if it is an interesting sext operations for the address type
    5155             :   /// promotion before trying to promote it, e.g., the ones with the right
    5156             :   /// type and used in memory accesses.
    5157       42309 :   bool ATPConsiderable = TTI->shouldConsiderAddressTypePromotion(
    5158             :       *Inst, AllowPromotionWithoutCommonHeader);
    5159       42309 :   TypePromotionTransaction TPT(RemovedInsts);
    5160             :   TypePromotionTransaction::ConstRestorationPt LastKnownGood =
    5161             :       TPT.getRestorationPoint();
    5162             :   SmallVector<Instruction *, 1> Exts;
    5163             :   SmallVector<Instruction *, 2> SpeculativelyMovedExts;
    5164       42309 :   Exts.push_back(Inst);
    5165             : 
    5166       42309 :   bool HasPromoted = tryToPromoteExts(TPT, Exts, SpeculativelyMovedExts);
    5167             : 
    5168             :   // Look for a load being extended.
    5169       42309 :   LoadInst *LI = nullptr;
    5170             :   Instruction *ExtFedByLoad;
    5171             : 
    5172             :   // Try to promote a chain of computation if it allows to form an extended
    5173             :   // load.
    5174       42309 :   if (canFormExtLd(SpeculativelyMovedExts, LI, ExtFedByLoad, HasPromoted)) {
    5175             :     assert(LI && ExtFedByLoad && "Expect a valid load and extension");
    5176             :     TPT.commit();
    5177             :     // Move the extend into the same block as the load
    5178        1367 :     ExtFedByLoad->moveAfter(LI);
    5179             :     // CGP does not check if the zext would be speculatively executed when moved
    5180             :     // to the same basic block as the load. Preserving its original location
    5181             :     // would pessimize the debugging experience, as well as negatively impact
    5182             :     // the quality of sample pgo. We don't want to use "line 0" as that has a
    5183             :     // size cost in the line-table section and logically the zext can be seen as
    5184             :     // part of the load. Therefore we conservatively reuse the same debug
    5185             :     // location for the load and the zext.
    5186        1367 :     ExtFedByLoad->setDebugLoc(LI->getDebugLoc());
    5187             :     ++NumExtsMoved;
    5188        1367 :     Inst = ExtFedByLoad;
    5189        1367 :     return true;
    5190             :   }
    5191             : 
    5192             :   // Continue promoting SExts if known as considerable depending on targets.
    5193       41088 :   if (ATPConsiderable &&
    5194         146 :       performAddressTypePromotion(Inst, AllowPromotionWithoutCommonHeader,
    5195             :                                   HasPromoted, TPT, SpeculativelyMovedExts))
    5196             :     return true;
    5197             : 
    5198       40890 :   TPT.rollback(LastKnownGood);
    5199       40890 :   return false;
    5200             : }
    5201             : 
    5202             : // Perform address type promotion if doing so is profitable.
    5203             : // If AllowPromotionWithoutCommonHeader == false, we should find other sext
    5204             : // instructions that sign extended the same initial value. However, if
    5205             : // AllowPromotionWithoutCommonHeader == true, we expect promoting the
    5206             : // extension is just profitable.
    5207         146 : bool CodeGenPrepare::performAddressTypePromotion(
    5208             :     Instruction *&Inst, bool AllowPromotionWithoutCommonHeader,
    5209             :     bool HasPromoted, TypePromotionTransaction &TPT,
    5210             :     SmallVectorImpl<Instruction *> &SpeculativelyMovedExts) {
    5211             :   bool Promoted = false;
    5212             :   SmallPtrSet<Instruction *, 1> UnhandledExts;
    5213             :   bool AllSeenFirst = true;
    5214         296 :   for (auto I : SpeculativelyMovedExts) {
    5215         150 :     Value *HeadOfChain = I->getOperand(0);
    5216             :     DenseMap<Value *, Instruction *>::iterator AlreadySeen =
    5217         150 :         SeenChainsForSExt.find(HeadOfChain);
    5218             :     // If there is an unhandled SExt which has the same header, try to promote
    5219             :     // it as well.
    5220         150 :     if (AlreadySeen != SeenChainsForSExt.end()) {
    5221          53 :       if (AlreadySeen->second != nullptr)
    5222          30 :         UnhandledExts.insert(AlreadySeen->second);
    5223             :       AllSeenFirst = false;
    5224             :     }
    5225             :   }
    5226             : 
    5227         146 :   if (!AllSeenFirst || (AllowPromotionWithoutCommonHeader &&
    5228          17 :                         SpeculativelyMovedExts.size() == 1)) {
    5229             :     TPT.commit();
    5230          70 :     if (HasPromoted)
    5231             :       Promoted = true;
    5232         141 :     for (auto I : SpeculativelyMovedExts) {
    5233          71 :       Value *HeadOfChain = I->getOperand(0);
    5234          71 :       SeenChainsForSExt[HeadOfChain] = nullptr;
    5235          71 :       ValToSExtendedUses[HeadOfChain].push_back(I);
    5236             :     }
    5237             :     // Update Inst as promotion happen.
    5238          70 :     Inst = SpeculativelyMovedExts.pop_back_val();
    5239             :   } else {
    5240             :     // This is the first chain visited from the header, keep the current chain
    5241             :     // as unhandled. Defer to promote this until we encounter another SExt
    5242             :     // chain derived from the same header.
    5243         155 :     for (auto I : SpeculativelyMovedExts) {
    5244          79 :       Value *HeadOfChain = I->getOperand(0);
    5245          79 :       SeenChainsForSExt[HeadOfChain] = Inst;
    5246             :     }
    5247             :     return false;
    5248             :   }
    5249             : 
    5250          70 :   if (!AllSeenFirst && !UnhandledExts.empty())
    5251          60 :     for (auto VisitedSExt : UnhandledExts) {
    5252          30 :       if (RemovedInsts.count(VisitedSExt))
    5253           0 :         continue;
    5254          30 :       TypePromotionTransaction TPT(RemovedInsts);
    5255             :       SmallVector<Instruction *, 1> Exts;
    5256             :       SmallVector<Instruction *, 2> Chains;
    5257          30 :       Exts.push_back(VisitedSExt);
    5258          30 :       bool HasPromoted = tryToPromoteExts(TPT, Exts, Chains);
    5259             :       TPT.commit();
    5260          30 :       if (HasPromoted)
    5261             :         Promoted = true;
    5262          62 :       for (auto I : Chains) {
    5263          32 :         Value *HeadOfChain = I->getOperand(0);
    5264             :         // Mark this as handled.
    5265          32 :         SeenChainsForSExt[HeadOfChain] = nullptr;
    5266          32 :         ValToSExtendedUses[HeadOfChain].push_back(I);
    5267             :       }
    5268             :     }
    5269             :   return Promoted;
    5270             : }
    5271             : 
    5272       42311 : bool CodeGenPrepare::optimizeExtUses(Instruction *I) {
    5273       42311 :   BasicBlock *DefBB = I->getParent();
    5274             : 
    5275             :   // If the result of a {s|z}ext and its source are both live out, rewrite all
    5276             :   // other uses of the source with result of extension.
    5277       42311 :   Value *Src = I->getOperand(0);
    5278       42311 :   if (Src->hasOneUse())
    5279             :     return false;
    5280             : 
    5281             :   // Only do this xform if truncating is free.
    5282        6849 :   if (TLI && !TLI->isTruncateFree(I->getType(), Src->getType()))
    5283             :     return false;
    5284             : 
    5285             :   // Only safe to perform the optimization if the source is also defined in
    5286             :   // this block.
    5287        6440 :   if (!isa<Instruction>(Src) || DefBB != cast<Instruction>(Src)->getParent())
    5288             :     return false;
    5289             : 
    5290             :   bool DefIsLiveOut = false;
    5291        8649 :   for (User *U : I->users()) {
    5292             :     Instruction *UI = cast<Instruction>(U);
    5293             : 
    5294             :     // Figure out which BB this ext is used in.
    5295        5585 :     BasicBlock *UserBB = UI->getParent();
    5296        5585 :     if (UserBB == DefBB) continue;
    5297             :     DefIsLiveOut = true;
    5298             :     break;
    5299             :   }
    5300        5320 :   if (!DefIsLiveOut)
    5301             :     return false;
    5302             : 
    5303             :   // Make sure none of the uses are PHI nodes.
    5304        7901 :   for (User *U : Src->users()) {
    5305             :     Instruction *UI = cast<Instruction>(U);
    5306        5808 :     BasicBlock *UserBB = UI->getParent();
    5307        5808 :     if (UserBB == DefBB) continue;
    5308             :     // Be conservative. We don't want this xform to end up introducing
    5309             :     // reloads just before load / store instructions.
    5310        1445 :     if (isa<PHINode>(UI) || isa<LoadInst>(UI) || isa<StoreInst>(UI))
    5311             :       return false;
    5312             :   }
    5313             : 
    5314             :   // InsertedTruncs - Only insert one trunc in each block once.
    5315             :   DenseMap<BasicBlock*, Instruction*> InsertedTruncs;
    5316             : 
    5317             :   bool MadeChange = false;
    5318        5788 :   for (Use &U : Src->uses()) {
    5319        3695 :     Instruction *User = cast<Instruction>(U.getUser());
    5320             : 
    5321             :     // Figure out which BB this ext is used in.
    5322        3695 :     BasicBlock *UserBB = User->getParent();
    5323        3695 :     if (UserBB == DefBB) continue;
    5324             : 
    5325             :     // Both src and def are live in this block. Rewrite the use.
    5326             :     Instruction *&InsertedTrunc = InsertedTruncs[UserBB];
    5327             : 
    5328         774 :     if (!InsertedTrunc) {
    5329         774 :       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
    5330             :       assert(InsertPt != UserBB->end());
    5331        1548 :       InsertedTrunc = new TruncInst(I, Src->getType(), "", &*InsertPt);
    5332         774 :       InsertedInsts.insert(InsertedTrunc);
    5333             :     }
    5334             : 
    5335             :     // Replace a use of the {s|z}ext source with a use of the result.
    5336         774 :     U = InsertedTrunc;
    5337             :     ++NumExtUses;
    5338             :     MadeChange = true;
    5339             :   }
    5340             : 
    5341             :   return MadeChange;
    5342             : }
    5343             : 
    5344             : // Find loads whose uses only use some of the loaded value's bits.  Add an "and"
    5345             : // just after the load if the target can fold this into one extload instruction,
    5346             : // with the hope of eliminating some of the other later "and" instructions using
    5347             : // the loaded value.  "and"s that are made trivially redundant by the insertion
    5348             : // of the new "and" are removed by this function, while others (e.g. those whose
    5349             : // path from the load goes through a phi) are left for isel to potentially
    5350             : // remove.
    5351             : //
    5352             : // For example:
    5353             : //
    5354             : // b0:
    5355             : //   x = load i32
    5356             : //   ...
    5357             : // b1:
    5358             : //   y = and x, 0xff
    5359             : //   z = use y
    5360             : //
    5361             : // becomes:
    5362             : //
    5363             : // b0:
    5364             : //   x = load i32
    5365             : //   x' = and x, 0xff
    5366             : //   ...
    5367             : // b1:
    5368             : //   z = use x'
    5369             : //
    5370             : // whereas:
    5371             : //
    5372             : // b0:
    5373             : //   x1 = load i32
    5374             : //   ...
    5375             : // b1:
    5376             : //   x2 = load i32
    5377             : //   ...
    5378             : // b2:
    5379             : //   x = phi x1, x2
    5380             : //   y = and x, 0xff
    5381             : //
    5382             : // becomes (after a call to optimizeLoadExt for each load):
    5383             : //
    5384             : // b0:
    5385             : //   x1 = load i32
    5386             : //   x1' = and x1, 0xff
    5387             : //   ...
    5388             : // b1:
    5389             : //   x2 = load i32
    5390             : //   x2' = and x2, 0xff
    5391             : //   ...
    5392             : // b2:
    5393             : //   x = phi x1', x2'
    5394             : //   y = and x, 0xff
    5395      914971 : bool CodeGenPrepare::optimizeLoadExt(LoadInst *Load) {
    5396      905525 :   if (!Load->isSimple() || !Load->getType()->isIntOrPtrTy())
    5397             :     return false;
    5398             : 
    5399             :   // Skip loads we've already transformed.
    5400     1297172 :   if (Load->hasOneUse() &&
    5401     1250010 :       InsertedInsts.count(cast<Instruction>(*Load->user_begin())))
    5402             :     return false;
    5403             : 
    5404             :   // Look at all uses of Load, looking through phis, to determine how many bits
    5405             :   // of the loaded value are needed.
    5406             :   SmallVector<Instruction *, 8> WorkList;
    5407             :   SmallPtrSet<Instruction *, 16> Visited;
    5408             :   SmallVector<Instruction *, 8> AndsToMaybeRemove;
    5409     1431052 :   for (auto *U : Load->users())
    5410      758251 :     WorkList.push_back(cast<Instruction>(U));
    5411             : 
    5412      672801 :   EVT LoadResultVT = TLI->getValueType(*DL, Load->getType());
    5413      672801 :   unsigned BitWidth = LoadResultVT.getSizeInBits();
    5414             :   APInt DemandBits(BitWidth, 0);
    5415             :   APInt WidestAndBits(BitWidth, 0);
    5416             : 
    5417      695135 :   while (!WorkList.empty()) {
    5418      687004 :     Instruction *I = WorkList.back();
    5419             :     WorkList.pop_back();
    5420             : 
    5421             :     // Break use-def graph loops.
    5422      687004 :     if (!Visited.insert(I).second)
    5423       12871 :       continue;
    5424             : 
    5425             :     // For a PHI node, push all of its users.
    5426      686783 :     if (auto *Phi = dyn_cast<PHINode>(I)) {
    5427       31577 :       for (auto *U : Phi->users())
    5428       18927 :         WorkList.push_back(cast<Instruction>(U));
    5429             :       continue;
    5430             :     }
    5431             : 
    5432      674133 :     switch (I->getOpcode()) {
    5433        8898 :     case Instruction::And: {
    5434        8898 :       auto *AndC = dyn_cast<ConstantInt>(I->getOperand(1));
    5435             :       if (!AndC)
    5436        1725 :         return false;
    5437             :       APInt AndBits = AndC->getValue();
    5438             :       DemandBits |= AndBits;
    5439             :       // Keep track of the widest and mask we see.
    5440        7173 :       if (AndBits.ugt(WidestAndBits))
    5441        6908 :         WidestAndBits = AndBits;
    5442       14178 :       if (AndBits == WidestAndBits && I->getOperand(0) == Load)
    5443        6539 :         AndsToMaybeRemove.push_back(I);
    5444             :       break;
    5445             :     }
    5446             : 
    5447        1318 :     case Instruction::Shl: {
    5448        1318 :       auto *ShlC = dyn_cast<ConstantInt>(I->getOperand(1));
    5449             :       if (!ShlC)
    5450             :         return false;
    5451         956 :       uint64_t ShiftAmt = ShlC->getLimitedValue(BitWidth - 1);
    5452         956 :       DemandBits.setLowBits(BitWidth - ShiftAmt);
    5453             :       break;
    5454             :     }
    5455             : 
    5456        1334 :     case Instruction::Trunc: {
    5457        1334 :       EVT TruncVT = TLI->getValueType(*DL, I->getType());
    5458        1334 :       unsigned TruncBitWidth = TruncVT.getSizeInBits();
    5459             :       DemandBits.setLowBits(TruncBitWidth);
    5460             :       break;
    5461             :     }
    5462             : 
    5463             :     default:
    5464             :       return false;
    5465             :     }
    5466             :   }
    5467             : 
    5468             :   uint32_t ActiveBits = DemandBits.getActiveBits();
    5469             :   // Avoid hoisting (and (load x) 1) since it is unlikely to be folded by the
    5470             :   // target even if isLoadExtLegal says an i1 EXTLOAD is valid.  For example,
    5471             :   // for the AArch64 target isLoadExtLegal(ZEXTLOAD, i32, i1) returns true, but
    5472             :   // (and (load x) 1) is not matched as a single instruction, rather as a LDR
    5473             :   // followed by an AND.
    5474             :   // TODO: Look into removing this restriction by fixing backends to either
    5475             :   // return false for isLoadExtLegal for i1 or have them select this pattern to
    5476             :   // a single instruction.
    5477             :   //
    5478             :   // Also avoid hoisting if we didn't see any ands with the exact DemandBits
    5479             :   // mask, since these are the only ands that will be removed by isel.
    5480       10483 :   if (ActiveBits <= 1 || !DemandBits.isMask(ActiveBits) ||
    5481             :       WidestAndBits != DemandBits)
    5482             :     return false;
    5483             : 
    5484         252 :   LLVMContext &Ctx = Load->getType()->getContext();
    5485         252 :   Type *TruncTy = Type::getIntNTy(Ctx, ActiveBits);
    5486         252 :   EVT TruncVT = TLI->getValueType(*DL, TruncTy);
    5487             : 
    5488             :   // Reject cases that won't be matched as extloads.
    5489         323 :   if (!LoadResultVT.bitsGT(TruncVT) || !TruncVT.isRound() ||
    5490          71 :       !TLI->isLoadExtLegal(ISD::ZEXTLOAD, LoadResultVT, TruncVT))
    5491             :     return false;
    5492             : 
    5493          71 :   IRBuilder<> Builder(Load->getNextNode());
    5494          71 :   auto *NewAnd = dyn_cast<Instruction>(
    5495          71 :       Builder.CreateAnd(Load, ConstantInt::get(Ctx, DemandBits)));
    5496             :   // Mark this instruction as "inserted by CGP", so that other
    5497             :   // optimizations don't touch it.
    5498          71 :   InsertedInsts.insert(NewAnd);
    5499             : 
    5500             :   // Replace all uses of load with new and (except for the use of load in the
    5501             :   // new and itself).
    5502          71 :   Load->replaceAllUsesWith(NewAnd);
    5503          71 :   NewAnd->setOperand(0, Load);
    5504             : 
    5505             :   // Remove any and instructions that are now redundant.
    5506         133 :   for (auto *And : AndsToMaybeRemove)
    5507             :     // Check that the and mask is the same as the one we decided to put on the
    5508             :     // new and.
    5509         124 :     if (cast<ConstantInt>(And->getOperand(1))->getValue() == DemandBits) {
    5510          62 :       And->replaceAllUsesWith(NewAnd);
    5511         124 :       if (&*CurInstIterator == And)
    5512          76 :         CurInstIterator = std::next(And->getIterator());
    5513          62 :       And->eraseFromParent();
    5514             :       ++NumAndUses;
    5515             :     }
    5516             : 
    5517             :   ++NumAndsAdded;
    5518             :   return true;
    5519             : }
    5520             : 
    5521             : /// Check if V (an operand of a select instruction) is an expensive instruction
    5522             : /// that is only used once.
    5523       10265 : static bool sinkSelectOperand(const TargetTransformInfo *TTI, Value *V) {
    5524             :   auto *I = dyn_cast<Instruction>(V);
    5525             :   // If it's safe to speculatively execute, then it should not have side
    5526             :   // effects; therefore, it's safe to sink and possibly *not* execute.
    5527        8837 :   return I && I->hasOneUse() && isSafeToSpeculativelyExecute(I) &&
    5528        2762 :          TTI->getUserCost(I) >= TargetTransformInfo::TCC_Expensive;
    5529             : }
    5530             : 
    5531             : /// Returns true if a SelectInst should be turned into an explicit branch.
    5532       15238 : static bool isFormingBranchFromSelectProfitable(const TargetTransformInfo *TTI,
    5533             :                                                 const TargetLowering *TLI,
    5534             :                                                 SelectInst *SI) {
    5535             :   // If even a predictable select is cheap, then a branch can't be cheaper.
    5536       15238 :   if (!TLI->isPredictableSelectExpensive())
    5537             :     return false;
    5538             : 
    5539             :   // FIXME: This should use the same heuristics as IfConversion to determine
    5540             :   // whether a select is better represented as a branch.
    5541             : 
    5542             :   // If metadata tells us that the select condition is obviously predictable,
    5543             :   // then we want to replace the select with a branch.
    5544             :   uint64_t TrueWeight, FalseWeight;
    5545        6709 :   if (SI->extractProfMetadata(TrueWeight, FalseWeight)) {
    5546           9 :     uint64_t Max = std::max(TrueWeight, FalseWeight);
    5547           9 :     uint64_t Sum = TrueWeight + FalseWeight;
    5548           9 :     if (Sum != 0) {
    5549           8 :       auto Probability = BranchProbability::getBranchProbability(Max, Sum);
    5550           8 :       if (Probability > TLI->getPredictableBranchThreshold())
    5551           7 :         return true;
    5552             :     }
    5553             :   }
    5554             : 
    5555             :   CmpInst *Cmp = dyn_cast<CmpInst>(SI->getCondition());
    5556             : 
    5557             :   // If a branch is predictable, an out-of-order CPU can avoid blocking on its
    5558             :   // comparison condition. If the compare has more than one use, there's
    5559             :   // probably another cmov or setcc around, so it's not worth emitting a branch.
    5560        5687 :   if (!Cmp || !Cmp->hasOneUse())
    5561             :     return false;
    5562             : 
    5563             :   // If either operand of the select is expensive and only needed on one side
    5564             :   // of the select, we should form a branch.
    5565       10211 :   if (sinkSelectOperand(TTI, SI->getTrueValue()) ||
    5566        5103 :       sinkSelectOperand(TTI, SI->getFalseValue()))
    5567           8 :     return true;
    5568             : 
    5569             :   return false;
    5570             : }
    5571             : 
    5572             : /// If \p isTrue is true, return the true value of \p SI, otherwise return
    5573             : /// false value of \p SI. If the true/false value of \p SI is defined by any
    5574             : /// select instructions in \p Selects, look through the defining select
    5575             : /// instruction until the true/false value is not defined in \p Selects.
    5576          54 : static Value *getTrueOrFalseValue(
    5577             :     SelectInst *SI, bool isTrue,
    5578             :     const SmallPtrSet<const Instruction *, 2> &Selects) {
    5579             :   Value *V;
    5580             : 
    5581         111 :   for (SelectInst *DefSI = SI; DefSI != nullptr && Selects.count(DefSI);
    5582             :        DefSI = dyn_cast<SelectInst>(V)) {
    5583             :     assert(DefSI->getCondition() == SI->getCondition() &&
    5584             :            "The condition of DefSI does not match with SI");
    5585          57 :     V = (isTrue ? DefSI->getTrueValue() : DefSI->getFalseValue());
    5586             :   }
    5587          54 :   return V;
    5588             : }
    5589             : 
    5590             : /// If we have a SelectInst that will likely profit from branch prediction,
    5591             : /// turn it into a branch.
    5592       37997 : bool CodeGenPrepare::optimizeSelectInst(SelectInst *SI) {
    5593             :   // If branch conversion isn't desirable, exit early.
    5594       37997 :   if (DisableSelectToBranch || OptSize || !TLI)
    5595             :     return false;
    5596             : 
    5597             :   // Find all consecutive select instructions that share the same condition.
    5598             :   SmallVector<SelectInst *, 2> ASI;
    5599       37871 :   ASI.push_back(SI);
    5600       37871 :   for (BasicBlock::iterator It = ++BasicBlock::iterator(SI);
    5601       77284 :        It != SI->getParent()->end(); ++It) {
    5602       38642 :     SelectInst *I = dyn_cast<SelectInst>(&*It);
    5603       38642 :     if (I && SI->getCondition() == I->getCondition()) {
    5604         771 :       ASI.push_back(I);
    5605             :     } else {
    5606             :       break;
    5607             :     }
    5608             :   }
    5609             : 
    5610       37871 :   SelectInst *LastSI = ASI.back();
    5611             :   // Increment the current iterator to skip all the rest of select instructions
    5612             :   // because they will be either "not lowered" or "all lowered" to branch.
    5613       75742 :   CurInstIterator = std::next(LastSI->getIterator());
    5614             : 
    5615       37871 :   bool VectorCond = !SI->getCondition()->getType()->isIntegerTy(1);
    5616             : 
    5617             :   // Can we convert the 'select' to CF ?
    5618       41946 :   if (VectorCond || SI->getMetadata(LLVMContext::MD_unpredictable))
    5619       22623 :     return false;
    5620             : 
    5621             :   TargetLowering::SelectSupportKind SelectKind;
    5622             :   if (VectorCond)
    5623             :     SelectKind = TargetLowering::VectorMaskSelect;
    5624       30496 :   else if (SI->getType()->isVectorTy())
    5625             :     SelectKind = TargetLowering::ScalarCondVectorVal;
    5626             :   else
    5627             :     SelectKind = TargetLowering::ScalarValSelect;
    5628             : 
    5629       30486 :   if (TLI->isSelectSupported(SelectKind) &&
    5630       15238 :       !isFormingBranchFromSelectProfitable(TTI, TLI, SI))
    5631             :     return false;
    5632             : 
    5633          25 :   ModifiedDT = true;
    5634             : 
    5635             :   // Transform a sequence like this:
    5636             :   //    start:
    5637             :   //       %cmp = cmp uge i32 %a, %b
    5638             :   //       %sel = select i1 %cmp, i32 %c, i32 %d
    5639             :   //
    5640             :   // Into:
    5641             :   //    start:
    5642             :   //       %cmp = cmp uge i32 %a, %b
    5643             :   //       br i1 %cmp, label %select.true, label %select.false
    5644             :   //    select.true:
    5645             :   //       br label %select.end
    5646             :   //    select.false:
    5647             :   //       br label %select.end
    5648             :   //    select.end:
    5649             :   //       %sel = phi i32 [ %c, %select.true ], [ %d, %select.false ]
    5650             :   //
    5651             :   // In addition, we may sink instructions that produce %c or %d from
    5652             :   // the entry block into the destination(s) of the new branch.
    5653             :   // If the true or false blocks do not contain a sunken instruction, that
    5654             :   // block and its branch may be optimized away. In that case, one side of the
    5655             :   // first branch will point directly to select.end, and the corresponding PHI
    5656             :   // predecessor block will be the start block.
    5657             : 
    5658             :   // First, we split the block containing the select into 2 blocks.
    5659          25 :   BasicBlock *StartBlock = SI->getParent();
    5660          25 :   BasicBlock::iterator SplitPt = ++(BasicBlock::iterator(LastSI));
    5661          25 :   BasicBlock *EndBlock = StartBlock->splitBasicBlock(SplitPt, "select.end");
    5662             : 
    5663             :   // Delete the unconditional branch that was just created by the split.
    5664          25 :   StartBlock->getTerminator()->eraseFromParent();
    5665             : 
    5666             :   // These are the new basic blocks for the conditional branch.
    5667             :   // At least one will become an actual new basic block.
    5668             :   BasicBlock *TrueBlock = nullptr;
    5669             :   BasicBlock *FalseBlock = nullptr;
    5670             :   BranchInst *TrueBranch = nullptr;
    5671             :   BranchInst *FalseBranch = nullptr;
    5672             : 
    5673             :   // Sink expensive instructions into the conditional blocks to avoid executing
    5674             :   // them speculatively.
    5675          52 :   for (SelectInst *SI : ASI) {
    5676          27 :     if (sinkSelectOperand(TTI, SI->getTrueValue())) {
    5677           5 :       if (TrueBlock == nullptr) {
    5678          15 :         TrueBlock = BasicBlock::Create(SI->getContext(), "select.true.sink",
    5679             :                                        EndBlock->getParent(), EndBlock);
    5680             :         TrueBranch = BranchInst::Create(EndBlock, TrueBlock);
    5681           5 :         TrueBranch->setDebugLoc(SI->getDebugLoc());
    5682             :       }
    5683             :       auto *TrueInst = cast<Instruction>(SI->getTrueValue());
    5684           5 :       TrueInst->moveBefore(TrueBranch);
    5685             :     }
    5686          27 :     if (sinkSelectOperand(TTI, SI->getFalseValue())) {
    5687           5 :       if (FalseBlock == nullptr) {
    5688          15 :         FalseBlock = BasicBlock::Create(SI->getContext(), "select.false.sink",
    5689             :                                         EndBlock->getParent(), EndBlock);
    5690             :         FalseBranch = BranchInst::Create(EndBlock, FalseBlock);
    5691           5 :         FalseBranch->setDebugLoc(SI->getDebugLoc());
    5692             :       }
    5693             :       auto *FalseInst = cast<Instruction>(SI->getFalseValue());
    5694           5 :       FalseInst->moveBefore(FalseBranch);
    5695             :     }
    5696             :   }
    5697             : 
    5698             :   // If there was nothing to sink, then arbitrarily choose the 'false' side
    5699             :   // for a new input value to the PHI.
    5700          25 :   if (TrueBlock == FalseBlock) {
    5701             :     assert(TrueBlock == nullptr &&
    5702             :            "Unexpected basic block transform while optimizing select");
    5703             : 
    5704          51 :     FalseBlock = BasicBlock::Create(SI->getContext(), "select.false",
    5705             :                                     EndBlock->getParent(), EndBlock);
    5706             :     auto *FalseBranch = BranchInst::Create(EndBlock, FalseBlock);
    5707          34 :     FalseBranch->setDebugLoc(SI->getDebugLoc());
    5708             :   }
    5709             : 
    5710             :   // Insert the real conditional branch based on the original condition.
    5711             :   // If we did not create a new block for one of the 'true' or 'false' paths
    5712             :   // of the condition, it means that side of the branch goes to the end block
    5713             :   // directly and the path originates from the start block from the point of
    5714             :   // view of the new PHI.
    5715             :   BasicBlock *TT, *FT;
    5716          25 :   if (TrueBlock == nullptr) {
    5717             :     TT = EndBlock;
    5718             :     FT = FalseBlock;
    5719             :     TrueBlock = StartBlock;
    5720           5 :   } else if (FalseBlock == nullptr) {
    5721             :     TT = TrueBlock;
    5722             :     FT = EndBlock;
    5723             :     FalseBlock = StartBlock;
    5724             :   } else {
    5725             :     TT = TrueBlock;
    5726             :     FT = FalseBlock;
    5727             :   }
    5728          50 :   IRBuilder<>(SI).CreateCondBr(SI->getCondition(), TT, FT, SI);
    5729             : 
    5730             :   SmallPtrSet<const Instruction *, 2> INS;
    5731             :   INS.insert(ASI.begin(), ASI.end());
    5732             :   // Use reverse iterator because later select may use the value of the
    5733             :   // earlier select, and we need to propagate value through earlier select
    5734             :   // to get the PHI operand.
    5735          52 :   for (auto It = ASI.rbegin(); It != ASI.rend(); ++It) {
    5736          27 :     SelectInst *SI = *It;
    5737             :     // The select itself is replaced with a PHI Node.
    5738          27 :     PHINode *PN = PHINode::Create(SI->getType(), 2, "", &EndBlock->front());
    5739          27 :     PN->takeName(SI);
    5740          27 :     PN->addIncoming(getTrueOrFalseValue(SI, true, INS), TrueBlock);
    5741          27 :     PN->addIncoming(getTrueOrFalseValue(SI, false, INS), FalseBlock);
    5742          27 :     PN->setDebugLoc(SI->getDebugLoc());
    5743             : 
    5744          27 :     SI->replaceAllUsesWith(PN);
    5745          27 :     SI->eraseFromParent();
    5746             :     INS.erase(SI);
    5747             :     ++NumSelectsExpanded;
    5748             :   }
    5749             : 
    5750             :   // Instruct OptimizeBlock to skip to the next block.
    5751          25 :   CurInstIterator = StartBlock->end();
    5752             :   return true;
    5753             : }
    5754             : 
    5755       18015 : static bool isBroadcastShuffle(ShuffleVectorInst *SVI) {
    5756             :   SmallVector<int, 16> Mask(SVI->getShuffleMask());
    5757             :   int SplatElem = -1;
    5758       57789 :   for (unsigned i = 0; i < Mask.size(); ++i) {
    5759       55561 :     if (SplatElem != -1 && Mask[i] != -1 && Mask[i] != SplatElem)
    5760             :       return false;
    5761       39774 :     SplatElem = Mask[i];
    5762             :   }
    5763             : 
    5764             :   return true;
    5765             : }
    5766             : 
    5767             : /// Some targets have expensive vector shifts if the lanes aren't all the same
    5768             : /// (e.g. x86 only introduced "vpsllvd" and friends with AVX2). In these cases
    5769             : /// it's often worth sinking a shufflevector splat down to its use so that
    5770             : /// codegen can spot all lanes are identical.
    5771           0 : bool CodeGenPrepare::optimizeShuffleVectorInst(ShuffleVectorInst *SVI) {
    5772           0 :   BasicBlock *DefBB = SVI->getParent();
    5773             : 
    5774             :   // Only do this xform if variable vector shifts are particularly expensive.
    5775           0 :   if (!TLI || !TLI->isVectorShiftByScalarCheap(SVI->getType()))
    5776           0 :     return false;
    5777             : 
    5778             :   // We only expect better codegen by sinking a shuffle if we can recognise a
    5779             :   // constant splat.
    5780           0 :   if (!isBroadcastShuffle(SVI))
    5781           0 :     return false;
    5782             : 
    5783             :   // InsertedShuffles - Only insert a shuffle in each block once.
    5784             :   DenseMap<BasicBlock*, Instruction*> InsertedShuffles;
    5785             : 
    5786             :   bool MadeChange = false;
    5787           0 :   for (User *U : SVI->users()) {
    5788             :     Instruction *UI = cast<Instruction>(U);
    5789             : 
    5790             :     // Figure out which BB this ext is used in.
    5791           0 :     BasicBlock *UserBB = UI->getParent();
    5792           0 :     if (UserBB == DefBB) continue;
    5793             : 
    5794             :     // For now only apply this when the splat is used by a shift instruction.
    5795           0 :     if (!UI->isShift()) continue;
    5796             : 
    5797             :     // Everything checks out, sink the shuffle if the user's block doesn't
    5798             :     // already have a copy.
    5799             :     Instruction *&InsertedShuffle = InsertedShuffles[UserBB];
    5800             : 
    5801           0 :     if (!InsertedShuffle) {
    5802           0 :       BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
    5803             :       assert(InsertPt != UserBB->end());
    5804           0 :       InsertedShuffle =
    5805             :           new ShuffleVectorInst(SVI->getOperand(0), SVI->getOperand(1),
    5806           0 :                                 SVI->getOperand(2), "", &*InsertPt);
    5807             :     }
    5808             : 
    5809           0 :     UI->replaceUsesOfWith(SVI, InsertedShuffle);
    5810             :     MadeChange = true;
    5811             :   }
    5812             : 
    5813             :   // If we removed all uses, nuke the shuffle.
    5814           0 :   if (SVI->use_empty()) {
    5815           0 :     SVI->eraseFromParent();
    5816             :     MadeChange = true;
    5817             :   }
    5818             : 
    5819             :   return MadeChange;
    5820             : }
    5821             : 
    5822           0 : bool CodeGenPrepare::optimizeSwitchInst(SwitchInst *SI) {
    5823           0 :   if (!TLI || !DL)
    5824           0 :     return false;
    5825             : 
    5826             :   Value *Cond = SI->getCondition();
    5827           0 :   Type *OldType = Cond->getType();
    5828           0 :   LLVMContext &Context = Cond->getContext();
    5829           0 :   MVT RegType = TLI->getRegisterType(Context, TLI->getValueType(*DL, OldType));
    5830           0 :   unsigned RegWidth = RegType.getSizeInBits();
    5831             : 
    5832           0 :   if (RegWidth <= cast<IntegerType>(OldType)->getBitWidth())
    5833           0 :     return false;
    5834             : 
    5835             :   // If the register width is greater than the type width, expand the condition
    5836             :   // of the switch instruction and each case constant to the width of the
    5837             :   // register. By widening the type of the switch condition, subsequent
    5838             :   // comparisons (for case comparisons) will not need to be extended to the
    5839             :   // preferred register width, so we will potentially eliminate N-1 extends,
    5840             :   // where N is the number of cases in the switch.
    5841           0 :   auto *NewType = Type::getIntNTy(Context, RegWidth);
    5842             : 
    5843             :   // Zero-extend the switch condition and case constants unless the switch
    5844             :   // condition is a function argument that is already being sign-extended.
    5845             :   // In that case, we can avoid an unnecessary mask/extension by sign-extending
    5846             :   // everything instead.
    5847             :   Instruction::CastOps ExtType = Instruction::ZExt;
    5848             :   if (auto *Arg = dyn_cast<Argument>(Cond))
    5849           0 :     if (Arg->hasSExtAttr())
    5850             :       ExtType = Instruction::SExt;
    5851             : 
    5852           0 :   auto *ExtInst = CastInst::Create(ExtType, Cond, NewType);
    5853           0 :   ExtInst->insertBefore(SI);
    5854           0 :   ExtInst->setDebugLoc(SI->getDebugLoc());
    5855             :   SI->setCondition(ExtInst);
    5856           0 :   for (auto Case : SI->cases()) {
    5857             :     APInt NarrowConst = Case.getCaseValue()->getValue();
    5858             :     APInt WideConst = (ExtType == Instruction::ZExt) ?
    5859           0 :                       NarrowConst.zext(RegWidth) : NarrowConst.sext(RegWidth);
    5860           0 :     Case.setValue(ConstantInt::get(Context, WideConst));
    5861             :   }
    5862             : 
    5863           0 :   return true;
    5864             : }
    5865             : 
    5866             : 
    5867             : namespace {
    5868             : 
    5869             : /// Helper class to promote a scalar operation to a vector one.
    5870             : /// This class is used to move downward extractelement transition.
    5871             : /// E.g.,
    5872             : /// a = vector_op <2 x i32>
    5873             : /// b = extractelement <2 x i32> a, i32 0
    5874             : /// c = scalar_op b
    5875             : /// store c
    5876             : ///
    5877             : /// =>
    5878             : /// a = vector_op <2 x i32>
    5879             : /// c = vector_op a (equivalent to scalar_op on the related lane)
    5880             : /// * d = extractelement <2 x i32> c, i32 0
    5881             : /// * store d
    5882             : /// Assuming both extractelement and store can be combine, we get rid of the
    5883             : /// transition.
    5884             : class VectorPromoteHelper {
    5885             :   /// DataLayout associated with the current module.
    5886             :   const DataLayout &DL;
    5887             : 
    5888             :   /// Used to perform some checks on the legality of vector operations.
    5889             :   const TargetLowering &TLI;
    5890             : 
    5891             :   /// Used to estimated the cost of the promoted chain.
    5892             :   const TargetTransformInfo &TTI;
    5893             : 
    5894             :   /// The transition being moved downwards.
    5895             :   Instruction *Transition;
    5896             : 
    5897             :   /// The sequence of instructions to be promoted.
    5898             :   SmallVector<Instruction *, 4> InstsToBePromoted;
    5899             : 
    5900             :   /// Cost of combining a store and an extract.
    5901             :   unsigned StoreExtractCombineCost;
    5902             : 
    5903             :   /// Instruction that will be combined with the transition.
    5904             :   Instruction *CombineInst = nullptr;
    5905             : 
    5906             :   /// The instruction that represents the current end of the transition.
    5907             :   /// Since we are faking the promotion until we reach the end of the chain
    5908             :   /// of computation, we need a way to get the current end of the transition.
    5909             :   Instruction *getEndOfTransition() const {
    5910         117 :     if (InstsToBePromoted.empty())
    5911          81 :       return Transition;
    5912          36 :     return InstsToBePromoted.back();
    5913             :   }
    5914             : 
    5915             :   /// Return the index of the original value in the transition.
    5916             :   /// E.g., for "extractelement <2 x i32> c, i32 1" the original value,
    5917             :   /// c, is at index 0.
    5918           0 :   unsigned getTransitionOriginalValueIdx() const {
    5919             :     assert(isa<ExtractElementInst>(Transition) &&
    5920             :            "Other kind of transitions are not supported yet");
    5921           0 :     return 0;
    5922             :   }
    5923             : 
    5924             :   /// Return the index of the index in the transition.
    5925             :   /// E.g., for "extractelement <2 x i32> c, i32 0" the index
    5926             :   /// is at index 1.
    5927           0 :   unsigned getTransitionIdx() const {
    5928             :     assert(isa<ExtractElementInst>(Transition) &&
    5929             :            "Other kind of transitions are not supported yet");
    5930           0 :     return 1;
    5931             :   }
    5932             : 
    5933             :   /// Get the type of the transition.
    5934             :   /// This is the type of the original value.
    5935             :   /// E.g., for "extractelement <2 x i32> c, i32 1" the type of the
    5936             :   /// transition is <2 x i32>.
    5937           0 :   Type *getTransitionType() const {
    5938          76 :     return Transition->getOperand(getTransitionOriginalValueIdx())->getType();
    5939             :   }
    5940             : 
    5941             :   /// Promote \p ToBePromoted by moving \p Def downward through.
    5942             :   /// I.e., we have the following sequence:
    5943             :   /// Def = Transition <ty1> a to <ty2>
    5944             :   /// b = ToBePromoted <ty2> Def, ...
    5945             :   /// =>
    5946             :   /// b = ToBePromoted <ty1> a, ...
    5947             :   /// Def = Transition <ty1> ToBePromoted to <ty2>
    5948             :   void promoteImpl(Instruction *ToBePromoted);
    5949             : 
    5950             :   /// Check whether or not it is profitable to promote all the
    5951             :   /// instructions enqueued to be promoted.
    5952           6 :   bool isProfitableToPromote() {
    5953           6 :     Value *ValIdx = Transition->getOperand(getTransitionOriginalValueIdx());
    5954             :     unsigned Index = isa<ConstantInt>(ValIdx)
    5955             :                          ? cast<ConstantInt>(ValIdx)->getZExtValue()
    5956           6 :                          : -1;
    5957             :     Type *PromotedType = getTransitionType();
    5958             : 
    5959           6 :     StoreInst *ST = cast<StoreInst>(CombineInst);
    5960             :     unsigned AS = ST->getPointerAddressSpace();
    5961             :     unsigned Align = ST->getAlignment();
    5962             :     // Check if this store is supported.
    5963           6 :     if (!TLI.allowsMisalignedMemoryAccesses(
    5964             :             TLI.getValueType(DL, ST->getValueOperand()->getType()), AS,
    5965           6 :             Align)) {
    5966             :       // If this is not supported, there is no way we can combine
    5967             :       // the extract with the store.
    5968             :       return false;
    5969             :     }
    5970             : 
    5971             :     // The scalar chain of computation has to pay for the transition
    5972             :     // scalar to vector.
    5973             :     // The vector chain has to account for the combining cost.
    5974             :     uint64_t ScalarCost =
    5975          12 :         TTI.getVectorInstrCost(Transition->getOpcode(), PromotedType, Index);
    5976           6 :     uint64_t VectorCost = StoreExtractCombineCost;
    5977          24 :     for (const auto &Inst : InstsToBePromoted) {
    5978             :       // Compute the cost.
    5979             :       // By construction, all instructions being promoted are arithmetic ones.
    5980             :       // Moreover, one argument is a constant that can be viewed as a splat
    5981             :       // constant.
    5982          18 :       Value *Arg0 = Inst->getOperand(0);
    5983          18 :       bool IsArg0Constant = isa<UndefValue>(Arg0) || isa<ConstantInt>(Arg0) ||
    5984             :                             isa<ConstantFP>(Arg0);
    5985             :       TargetTransformInfo::OperandValueKind Arg0OVK =
    5986             :           IsArg0Constant ? TargetTransformInfo::OK_UniformConstantValue
    5987             :                          : TargetTransformInfo::OK_AnyValue;
    5988             :       TargetTransformInfo::OperandValueKind Arg1OVK =
    5989          18 :           !IsArg0Constant ? TargetTransformInfo::OK_UniformConstantValue
    5990             :                           : TargetTransformInfo::OK_AnyValue;
    5991          18 :       ScalarCost += TTI.getArithmeticInstrCost(
    5992          18 :           Inst->getOpcode(), Inst->getType(), Arg0OVK, Arg1OVK);
    5993          18 :       VectorCost += TTI.getArithmeticInstrCost(Inst->getOpcode(), PromotedType,
    5994          18 :                                                Arg0OVK, Arg1OVK);
    5995             :     }
    5996             :     LLVM_DEBUG(
    5997             :         dbgs() << "Estimated cost of computation to be promoted:\nScalar: "
    5998             :                << ScalarCost << "\nVector: " << VectorCost << '\n');
    5999           6 :     return ScalarCost > VectorCost;
    6000             :   }
    6001             : 
    6002             :   /// Generate a constant vector with \p Val with the same
    6003             :   /// number of elements as the transition.
    6004             :   /// \p UseSplat defines whether or not \p Val should be replicated
    6005             :   /// across the whole vector.
    6006             :   /// In other words, if UseSplat == true, we generate <Val, Val, ..., Val>,
    6007             :   /// otherwise we generate a vector with as many undef as possible:
    6008             :   /// <undef, ..., undef, Val, undef, ..., undef> where \p Val is only
    6009             :   /// used at the index of the extract.
    6010          38 :   Value *getConstantVector(Constant *Val, bool UseSplat) const {
    6011             :     unsigned ExtractIdx = std::numeric_limits<unsigned>::max();
    6012          38 :     if (!UseSplat) {
    6013             :       // If we cannot determine where the constant must be, we have to
    6014             :       // use a splat constant.
    6015          32 :       Value *ValExtractIdx = Transition->getOperand(getTransitionIdx());
    6016             :       if (ConstantInt *CstVal = dyn_cast<ConstantInt>(ValExtractIdx))
    6017          31 :         ExtractIdx = CstVal->getSExtValue();
    6018             :       else
    6019             :         UseSplat = true;
    6020             :     }
    6021             : 
    6022          38 :     unsigned End = getTransitionType()->getVectorNumElements();
    6023          38 :     if (UseSplat)
    6024           7 :       return ConstantVector::getSplat(End, Val);
    6025             : 
    6026             :     SmallVector<Constant *, 4> ConstVec;
    6027          31 :     UndefValue *UndefVal = UndefValue::get(Val->getType());
    6028         105 :     for (unsigned Idx = 0; Idx != End; ++Idx) {
    6029          74 :       if (Idx == ExtractIdx)
    6030          31 :         ConstVec.push_back(Val);
    6031             :       else
    6032          43 :         ConstVec.push_back(UndefVal);
    6033             :     }
    6034          31 :     return ConstantVector::get(ConstVec);
    6035             :   }
    6036             : 
    6037             :   /// Check if promoting to a vector type an operand at \p OperandIdx
    6038             :   /// in \p Use can trigger undefined behavior.
    6039          96 :   static bool canCauseUndefinedBehavior(const Instruction *Use,
    6040             :                                         unsigned OperandIdx) {
    6041             :     // This is not safe to introduce undef when the operand is on
    6042             :     // the right hand side of a division-like instruction.
    6043          96 :     if (OperandIdx != 1)
    6044             :       return false;
    6045             :     switch (Use->getOpcode()) {
    6046             :     default:
    6047             :       return false;
    6048             :     case Instruction::SDiv:
    6049             :     case Instruction::UDiv:
    6050             :     case Instruction::SRem:
    6051             :     case Instruction::URem:
    6052             :       return true;
    6053           4 :     case Instruction::FDiv:
    6054             :     case Instruction::FRem:
    6055           4 :       return !Use->hasNoNaNs();
    6056             :     }
    6057             :     llvm_unreachable(nullptr);
    6058             :   }
    6059             : 
    6060             : public:
    6061             :   VectorPromoteHelper(const DataLayout &DL, const TargetLowering &TLI,
    6062             :                       const TargetTransformInfo &TTI, Instruction *Transition,
    6063             :                       unsigned CombineCost)
    6064         138 :       : DL(DL), TLI(TLI), TTI(TTI), Transition(Transition),
    6065         138 :         StoreExtractCombineCost(CombineCost) {
    6066             :     assert(Transition && "Do not know how to promote null");
    6067             :   }
    6068             : 
    6069             :   /// Check if we can promote \p ToBePromoted to \p Type.
    6070           0 :   bool canPromote(const Instruction *ToBePromoted) const {
    6071             :     // We could support CastInst too.
    6072           0 :     return isa<BinaryOperator>(ToBePromoted);
    6073             :   }
    6074             : 
    6075             :   /// Check if it is profitable to promote \p ToBePromoted
    6076             :   /// by moving downward the transition through.
    6077          59 :   bool shouldPromote(const Instruction *ToBePromoted) const {
    6078             :     // Promote only if all the operands can be statically expanded.
    6079             :     // Indeed, we do not want to introduce any new kind of transitions.
    6080         227 :     for (const Use &U : ToBePromoted->operands()) {
    6081         117 :       const Value *Val = U.get();
    6082         117 :       if (Val == getEndOfTransition()) {
    6083             :         // If the use is a division and the transition is on the rhs,
    6084             :         // we cannot promote the operation, otherwise we may create a
    6085             :         // division by zero.
    6086          58 :         if (canCauseUndefinedBehavior(ToBePromoted, U.getOperandNo()))
    6087             :           return false;
    6088             :         continue;
    6089             :       }
    6090          59 :       if (!isa<ConstantInt>(Val) && !isa<UndefValue>(Val) &&
    6091             :           !isa<ConstantFP>(Val))
    6092             :         return false;
    6093             :     }
    6094             :     // Check that the resulting operation is legal.
    6095         102 :     int ISDOpcode = TLI.InstructionOpcodeToISD(ToBePromoted->getOpcode());
    6096          51 :     if (!ISDOpcode)
    6097             :       return false;
    6098          81 :     return StressStoreExtract ||
    6099          60 :            TLI.isOperationLegalOrCustom(
    6100             :                ISDOpcode, TLI.getValueType(DL, getTransitionType(), true));
    6101             :   }
    6102             : 
    6103             :   /// Check whether or not \p Use can be combined
    6104             :   /// with the transition.
    6105             :   /// I.e., is it possible to do Use(Transition) => AnotherUse?
    6106           0 :   bool canCombine(const Instruction *Use) { return isa<StoreInst>(Use); }
    6107             : 
    6108             :   /// Record \p ToBePromoted as part of the chain to be promoted.
    6109             :   void enqueueForPromotion(Instruction *ToBePromoted) {
    6110          41 :     InstsToBePromoted.push_back(ToBePromoted);
    6111             :   }
    6112             : 
    6113             :   /// Set the instruction that will be combined with the transition.
    6114           0 :   void recordCombineInstruction(Instruction *ToBeCombined) {
    6115             :     assert(canCombine(ToBeCombined) && "Unsupported instruction to combine");
    6116          73 :     CombineInst = ToBeCombined;
    6117           0 :   }
    6118             : 
    6119             :   /// Promote all the instructions enqueued for promotion if it is
    6120             :   /// is profitable.
    6121             :   /// \return True if the promotion happened, false otherwise.
    6122          73 :   bool promote() {
    6123             :     // Check if there is something to promote.
    6124             :     // Right now, if we do not have anything to combine with,
    6125             :     // we assume the promotion is not profitable.
    6126          73 :     if (InstsToBePromoted.empty() || !CombineInst)
    6127             :       return false;
    6128             : 
    6129             :     // Check cost.
    6130          20 :     if (!StressStoreExtract && !isProfitableToPromote())
    6131             :       return false;
    6132             : 
    6133             :     // Promote.
    6134          58 :     for (auto &ToBePromoted : InstsToBePromoted)
    6135          38 :       promoteImpl(ToBePromoted);
    6136             :     InstsToBePromoted.clear();
    6137          20 :     return true;
    6138             :   }
    6139             : };
    6140             : 
    6141             : } // end anonymous namespace
    6142             : 
    6143          38 : void VectorPromoteHelper::promoteImpl(Instruction *ToBePromoted) {
    6144             :   // At this point, we know that all the operands of ToBePromoted but Def
    6145             :   // can be statically promoted.
    6146             :   // For Def, we need to use its parameter in ToBePromoted:
    6147             :   // b = ToBePromoted ty1 a
    6148             :   // Def = Transition ty1 b to ty2
    6149             :   // Move the transition down.
    6150             :   // 1. Replace all uses of the promoted operation by the transition.
    6151             :   // = ... b => = ... Def.
    6152             :   assert(ToBePromoted->getType() == Transition->getType() &&
    6153             :          "The type of the result of the transition does not match "
    6154             :          "the final type");
    6155          38 :   ToBePromoted->replaceAllUsesWith(Transition);
    6156             :   // 2. Update the type of the uses.
    6157             :   // b = ToBePromoted ty2 Def => b = ToBePromoted ty1 Def.
    6158          38 :   Type *TransitionTy = getTransitionType();
    6159             :   ToBePromoted->mutateType(TransitionTy);
    6160             :   // 3. Update all the operands of the promoted operation with promoted
    6161             :   // operands.
    6162             :   // b = ToBePromoted ty1 Def => b = ToBePromoted ty1 a.
    6163         152 :   for (Use &U : ToBePromoted->operands()) {
    6164          76 :     Value *Val = U.get();
    6165             :     Value *NewVal = nullptr;
    6166          76 :     if (Val == Transition)
    6167          38 :       NewVal = Transition->getOperand(getTransitionOriginalValueIdx());
    6168          38 :     else if (isa<UndefValue>(Val) || isa<ConstantInt>(Val) ||
    6169             :              isa<ConstantFP>(Val)) {
    6170             :       // Use a splat constant if it is not safe to use undef.
    6171          38 :       NewVal = getConstantVector(
    6172             :           cast<Constant>(Val),
    6173          76 :           isa<UndefValue>(Val) ||
    6174          38 :               canCauseUndefinedBehavior(ToBePromoted, U.getOperandNo()));
    6175             :     } else
    6176           0 :       llvm_unreachable("Did you modified shouldPromote and forgot to update "
    6177             :                        "this?");
    6178          76 :     ToBePromoted->setOperand(U.getOperandNo(), NewVal);
    6179             :   }
    6180          38 :   Transition->moveAfter(ToBePromoted);
    6181          38 :   Transition->setOperand(getTransitionOriginalValueIdx(), ToBePromoted);
    6182          38 : }
    6183             : 
    6184             : /// Some targets can do store(extractelement) with one instruction.
    6185             : /// Try to push the extractelement towards the stores when the target
    6186             : /// has this feature and this is profitable.
    6187       30205 : bool CodeGenPrepare::optimizeExtractElementInst(Instruction *Inst) {
    6188       30205 :   unsigned CombineCost = std::numeric_limits<unsigned>::max();
    6189       30205 :   if (DisableStoreExtract || !TLI ||
    6190       30158 :       (!StressStoreExtract &&
    6191       30158 :        !TLI->canCombineStoreAndExtract(Inst->getOperand(0)->getType(),
    6192       30158 :                                        Inst->getOperand(1), CombineCost)))
    6193       30067 :     return false;
    6194             : 
    6195             :   // At this point we know that Inst is a vector to scalar transition.
    6196             :   // Try to move it down the def-use chain, until:
    6197             :   // - We can combine the transition with its single use
    6198             :   //   => we got rid of the transition.
    6199             :   // - We escape the current basic block
    6200             :   //   => we would need to check that we are moving it at a cheaper place and
    6201             :   //      we do not do that for now.
    6202         138 :   BasicBlock *Parent = Inst->getParent();
    6203             :   LLVM_DEBUG(dbgs() << "Found an interesting transition: " << *Inst << '\n');
    6204         138 :   VectorPromoteHelper VPH(*DL, *TLI, *TTI, Inst, CombineCost);
    6205             :   // If the transition has more than one use, assume this is not going to be
    6206             :   // beneficial.
    6207         179 :   while (Inst->hasOneUse()) {
    6208             :     Instruction *ToBePromoted = cast<Instruction>(*Inst->user_begin());
    6209             :     LLVM_DEBUG(dbgs() << "Use: " << *ToBePromoted << '\n');
    6210             : 
    6211         166 :     if (ToBePromoted->getParent() != Parent) {
    6212             :       LLVM_DEBUG(dbgs() << "Instruction to promote is in a different block ("
    6213             :                         << ToBePromoted->getParent()->getName()
    6214             :                         << ") than the transition (" << Parent->getName()
    6215             :                         << ").\n");
    6216             :       return false;
    6217             :     }
    6218             : 
    6219         163 :     if (VPH.canCombine(ToBePromoted)) {
    6220             :       LLVM_DEBUG(dbgs() << "Assume " << *Inst << '\n'
    6221             :                         << "will be combined with: " << *ToBePromoted << '\n');
    6222             :       VPH.recordCombineInstruction(ToBePromoted);
    6223          73 :       bool Changed = VPH.promote();
    6224             :       NumStoreExtractExposed += Changed;
    6225          73 :       return Changed;
    6226             :     }
    6227             : 
    6228             :     LLVM_DEBUG(dbgs() << "Try promoting.\n");
    6229          90 :     if (!VPH.canPromote(ToBePromoted) || !VPH.shouldPromote(ToBePromoted))
    6230          49 :       return false;
    6231             : 
    6232             :     LLVM_DEBUG(dbgs() << "Promoting is possible... Enqueue for promotion!\n");
    6233             : 
    6234          41 :     VPH.enqueueForPromotion(ToBePromoted);
    6235             :     Inst = ToBePromoted;
    6236             :   }
    6237             :   return false;
    6238             : }
    6239             : 
    6240             : /// For the instruction sequence of store below, F and I values
    6241             : /// are bundled together as an i64 value before being stored into memory.
    6242             : /// Sometimes it is more efficient to generate separate stores for F and I,
    6243             : /// which can remove the bitwise instructions or sink them to colder places.
    6244             : ///
    6245             : ///   (store (or (zext (bitcast F to i32) to i64),
    6246             : ///              (shl (zext I to i64), 32)), addr)  -->
    6247             : ///   (store F, addr) and (store I, addr+4)
    6248             : ///
    6249             : /// Similarly, splitting for other merged store can also be beneficial, like:
    6250             : /// For pair of {i32, i32}, i64 store --> two i32 stores.
    6251             : /// For pair of {i32, i16}, i64 store --> two i32 stores.
    6252             : /// For pair of {i16, i16}, i32 store --> two i16 stores.
    6253             : /// For pair of {i16, i8},  i32 store --> two i16 stores.
    6254             : /// For pair of {i8, i8},   i16 store --> two i8 stores.
    6255             : ///
    6256             : /// We allow each target to determine specifically which kind of splitting is
    6257             : /// supported.
    6258             : ///
    6259             : /// The store patterns are commonly seen from the simple code snippet below
    6260             : /// if only std::make_pair(...) is sroa transformed before inlined into hoo.
    6261             : ///   void goo(const std::pair<int, float> &);
    6262             : ///   hoo() {
    6263             : ///     ...
    6264             : ///     goo(std::make_pair(tmp, ftmp));
    6265             : ///     ...
    6266             : ///   }
    6267             : ///
    6268             : /// Although we already have similar splitting in DAG Combine, we duplicate
    6269             : /// it in CodeGenPrepare to catch the case in which pattern is across
    6270             : /// multiple BBs. The logic in DAG Combine is kept to catch case generated
    6271             : /// during code expansion.
    6272      791326 : static bool splitMergedValStore(StoreInst &SI, const DataLayout &DL,
    6273             :                                 const TargetLowering &TLI) {
    6274             :   // Handle simple but common cases only.
    6275      791326 :   Type *StoreType = SI.getValueOperand()->getType();
    6276     1581070 :   if (DL.getTypeStoreSizeInBits(StoreType) != DL.getTypeSizeInBits(StoreType) ||
    6277      789744 :       DL.getTypeSizeInBits(StoreType) == 0)
    6278        1613 :     return false;
    6279             : 
    6280      789713 :   unsigned HalfValBitSize = DL.getTypeSizeInBits(StoreType) / 2;
    6281      789713 :   Type *SplitStoreType = Type::getIntNTy(SI.getContext(), HalfValBitSize);
    6282      789713 :   if (DL.getTypeStoreSizeInBits(SplitStoreType) !=
    6283      789713 :       DL.getTypeSizeInBits(SplitStoreType))
    6284             :     return false;
    6285             : 
    6286             :   // Match the following patterns:
    6287             :   // (store (or (zext LValue to i64),
    6288             :   //            (shl (zext HValue to i64), 32)), HalfValBitSize)
    6289             :   //  or
    6290             :   // (store (or (shl (zext HValue to i64), 32)), HalfValBitSize)
    6291             :   //            (zext LValue to i64),
    6292             :   // Expect both operands of OR and the first operand of SHL have only
    6293             :   // one use.
    6294             :   Value *LValue, *HValue;
    6295      772125 :   if (!match(SI.getValueOperand(),
    6296      772125 :              m_c_Or(m_OneUse(m_ZExt(m_Value(LValue))),
    6297             :                     m_OneUse(m_Shl(m_OneUse(m_ZExt(m_Value(HValue))),
    6298             :                                    m_SpecificInt(HalfValBitSize))))))
    6299             :     return false;
    6300             : 
    6301             :   // Check LValue and HValue are int with size less or equal than 32.
    6302         138 :   if (!LValue->getType()->isIntegerTy() ||
    6303         138 :       DL.getTypeSizeInBits(LValue->getType()) > HalfValBitSize ||
    6304         207 :       !HValue->getType()->isIntegerTy() ||
    6305          69 :       DL.getTypeSizeInBits(HValue->getType()) > HalfValBitSize)
    6306           0 :     return false;
    6307             : 
    6308             :   // If LValue/HValue is a bitcast instruction, use the EVT before bitcast
    6309             :   // as the input of target query.
    6310          69 :   auto *LBC = dyn_cast<BitCastInst>(LValue);
    6311          69 :   auto *HBC = dyn_cast<BitCastInst>(HValue);
    6312           1 :   EVT LowTy = LBC ? EVT::getEVT(LBC->getOperand(0)->getType())
    6313          69 :                   : EVT::getEVT(LValue->getType());
    6314           6 :   EVT HighTy = HBC ? EVT::getEVT(HBC->getOperand(0)->getType())
    6315          69 :                    : EVT::getEVT(HValue->getType());
    6316          69 :   if (!ForceSplitStore && !TLI.isMultiStoresCheaperThanBitsMerge(LowTy, HighTy))
    6317             :     return false;
    6318             : 
    6319             :   // Start to split store.
    6320          15 :   IRBuilder<> Builder(SI.getContext());
    6321          15 :   Builder.SetInsertPoint(&SI);
    6322             : 
    6323             :   // If LValue/HValue is a bitcast in another BB, create a new one in current
    6324             :   // BB so it may be merged with the splitted stores by dag combiner.
    6325          15 :   if (LBC && LBC->getParent() != SI.getParent())
    6326           0 :     LValue = Builder.CreateBitCast(LBC->getOperand(0), LBC->getType());
    6327          15 :   if (HBC && HBC->getParent() != SI.getParent())
    6328           6 :     HValue = Builder.CreateBitCast(HBC->getOperand(0), HBC->getType());
    6329             : 
    6330          15 :   bool IsLE = SI.getModule()->getDataLayout().isLittleEndian();
    6331             :   auto CreateSplitStore = [&](Value *V, bool Upper) {
    6332             :     V = Builder.CreateZExtOrBitCast(V, SplitStoreType);
    6333             :     Value *Addr = Builder.CreateBitCast(
    6334             :         SI.getOperand(1),
    6335             :         SplitStoreType->getPointerTo(SI.getPointerAddressSpace()));
    6336             :     if ((IsLE && Upper) || (!IsLE && !Upper))
    6337             :       Addr = Builder.CreateGEP(
    6338             :           SplitStoreType, Addr,
    6339             :           ConstantInt::get(Type::getInt32Ty(SI.getContext()), 1));
    6340             :     Builder.CreateAlignedStore(
    6341             :         V, Addr, Upper ? SI.getAlignment() / 2 : SI.getAlignment());
    6342          15 :   };
    6343             : 
    6344          15 :   CreateSplitStore(LValue, false);
    6345          15 :   CreateSplitStore(HValue, true);
    6346             : 
    6347             :   // Delete the old store.
    6348          15 :   SI.eraseFromParent();
    6349             :   return true;
    6350             : }
    6351             : 
    6352             : // Return true if the GEP has two operands, the first operand is of a sequential
    6353             : // type, and the second operand is a constant.
    6354          86 : static bool GEPSequentialConstIndexed(GetElementPtrInst *GEP) {
    6355          86 :   gep_type_iterator I = gep_type_begin(*GEP);
    6356          21 :   return GEP->getNumOperands() == 2 &&
    6357         107 :       I.isSequential() &&
    6358          86 :       isa<ConstantInt>(GEP->getOperand(1));
    6359             : }
    6360             : 
    6361             : // Try unmerging GEPs to reduce liveness interference (register pressure) across
    6362             : // IndirectBr edges. Since IndirectBr edges tend to touch on many blocks,
    6363             : // reducing liveness interference across those edges benefits global register
    6364             : // allocation. Currently handles only certain cases.
    6365             : //
    6366             : // For example, unmerge %GEPI and %UGEPI as below.
    6367             : //
    6368             : // ---------- BEFORE ----------
    6369             : // SrcBlock:
    6370             : //   ...
    6371             : //   %GEPIOp = ...
    6372             : //   ...
    6373             : //   %GEPI = gep %GEPIOp, Idx
    6374             : //   ...
    6375             : //   indirectbr ... [ label %DstB0, label %DstB1, ... label %DstBi ... ]
    6376             : //   (* %GEPI is alive on the indirectbr edges due to other uses ahead)
    6377             : //   (* %GEPIOp is alive on the indirectbr edges only because of it's used by
    6378             : //   %UGEPI)
    6379             : //
    6380             : // DstB0: ... (there may be a gep similar to %UGEPI to be unmerged)
    6381             : // DstB1: ... (there may be a gep similar to %UGEPI to be unmerged)
    6382             : // ...
    6383             : //
    6384             : // DstBi:
    6385             : //   ...
    6386             : //   %UGEPI = gep %GEPIOp, UIdx
    6387             : // ...
    6388             : // ---------------------------
    6389             : //
    6390             : // ---------- AFTER ----------
    6391             : // SrcBlock:
    6392             : //   ... (same as above)
    6393             : //    (* %GEPI is still alive on the indirectbr edges)
    6394             : //    (* %GEPIOp is no longer alive on the indirectbr edges as a result of the
    6395             : //    unmerging)
    6396             : // ...
    6397             : //
    6398             : // DstBi:
    6399             : //   ...
    6400             : //   %UGEPI = gep %GEPI, (UIdx-Idx)
    6401             : //   ...
    6402             : // ---------------------------
    6403             : //
    6404             : // The register pressure on the IndirectBr edges is reduced because %GEPIOp is
    6405             : // no longer alive on them.
    6406             : //
    6407             : // We try to unmerge GEPs here in CodGenPrepare, as opposed to limiting merging
    6408             : // of GEPs in the first place in InstCombiner::visitGetElementPtrInst() so as
    6409             : // not to disable further simplications and optimizations as a result of GEP
    6410             : // merging.
    6411             : //
    6412             : // Note this unmerging may increase the length of the data flow critical path
    6413             : // (the path from %GEPIOp to %UGEPI would go through %GEPI), which is a tradeoff
    6414             : // between the register pressure and the length of data-flow critical
    6415             : // path. Restricting this to the uncommon IndirectBr case would minimize the
    6416             : // impact of potentially longer critical path, if any, and the impact on compile
    6417             : // time.
    6418      209279 : static bool tryUnmergingGEPsAcrossIndirectBr(GetElementPtrInst *GEPI,
    6419             :                                              const TargetTransformInfo *TTI) {
    6420      209279 :   BasicBlock *SrcBlock = GEPI->getParent();
    6421             :   // Check that SrcBlock ends with an IndirectBr. If not, give up. The common
    6422             :   // (non-IndirectBr) cases exit early here.
    6423      209279 :   if (!isa<IndirectBrInst>(SrcBlock->getTerminator()))
    6424             :     return false;
    6425             :   // Check that GEPI is a simple gep with a single constant index.
    6426          83 :   if (!GEPSequentialConstIndexed(GEPI))
    6427             :     return false;
    6428             :   ConstantInt *GEPIIdx = cast<ConstantInt>(GEPI->getOperand(1));
    6429             :   // Check that GEPI is a cheap one.
    6430           8 :   if (TTI->getIntImmCost(GEPIIdx->getValue(), GEPIIdx->getType())
    6431             :       > TargetTransformInfo::TCC_Basic)
    6432             :     return false;
    6433             :   Value *GEPIOp = GEPI->getOperand(0);
    6434             :   // Check that GEPIOp is an instruction that's also defined in SrcBlock.
    6435           8 :   if (!isa<Instruction>(GEPIOp))
    6436             :     return false;
    6437             :   auto *GEPIOpI = cast<Instruction>(GEPIOp);
    6438           8 :   if (GEPIOpI->getParent() != SrcBlock)
    6439             :     return false;
    6440             :   // Check that GEP is used outside the block, meaning it's alive on the
    6441             :   // IndirectBr edge(s).
    6442           8 :   if (find_if(GEPI->users(), [&](User *Usr) {
    6443             :         if (auto *I = dyn_cast<Instruction>(Usr)) {
    6444           0 :           if (I->getParent() != SrcBlock) {
    6445             :             return true;
    6446             :           }
    6447             :         }
    6448             :         return false;
    6449             :       }) == GEPI->users().end())
    6450             :     return false;
    6451             :   // The second elements of the GEP chains to be unmerged.
    6452             :   std::vector<GetElementPtrInst *> UGEPIs;
    6453             :   // Check each user of GEPIOp to check if unmerging would make GEPIOp not alive
    6454             :   // on IndirectBr edges.
    6455          21 :   for (User *Usr : GEPIOp->users()) {
    6456          21 :     if (Usr == GEPI) continue;
    6457             :     // Check if Usr is an Instruction. If not, give up.
    6458           9 :     if (!isa<Instruction>(Usr))
    6459           0 :       return false;
    6460             :     auto *UI = cast<Instruction>(Usr);
    6461             :     // Check if Usr in the same block as GEPIOp, which is fine, skip.
    6462           9 :     if (UI->getParent() == SrcBlock)
    6463             :       continue;
    6464             :     // Check if Usr is a GEP. If not, give up.
    6465             :     if (!isa<GetElementPtrInst>(Usr))
    6466             :       return false;
    6467           3 :     auto *UGEPI = cast<GetElementPtrInst>(Usr);
    6468             :     // Check if UGEPI is a simple gep with a single constant index and GEPIOp is
    6469             :     // the pointer operand to it. If so, record it in the vector. If not, give
    6470             :     // up.
    6471           3 :     if (!GEPSequentialConstIndexed(UGEPI))
    6472             :       return false;
    6473           3 :     if (UGEPI->getOperand(0) != GEPIOp)
    6474             :       return false;
    6475           3 :     if (GEPIIdx->getType() !=
    6476             :         cast<ConstantInt>(UGEPI->getOperand(1))->getType())
    6477             :       return false;
    6478             :     ConstantInt *UGEPIIdx = cast<ConstantInt>(UGEPI->getOperand(1));
    6479           3 :     if (TTI->getIntImmCost(UGEPIIdx->getValue(), UGEPIIdx->getType())
    6480             :         > TargetTransformInfo::TCC_Basic)
    6481             :       return false;
    6482           3 :     UGEPIs.push_back(UGEPI);
    6483             :   }
    6484           6 :   if (UGEPIs.size() == 0)
    6485             :     return false;
    6486             :   // Check the materializing cost of (Uidx-Idx).
    6487           4 :   for (GetElementPtrInst *UGEPI : UGEPIs) {
    6488             :     ConstantInt *UGEPIIdx = cast<ConstantInt>(UGEPI->getOperand(1));
    6489           3 :     APInt NewIdx = UGEPIIdx->getValue() - GEPIIdx->getValue();
    6490           3 :     unsigned ImmCost = TTI->getIntImmCost(NewIdx, GEPIIdx->getType());
    6491           3 :     if (ImmCost > TargetTransformInfo::TCC_Basic)
    6492             :       return false;
    6493             :   }
    6494             :   // Now unmerge between GEPI and UGEPIs.
    6495           4 :   for (GetElementPtrInst *UGEPI : UGEPIs) {
    6496             :     UGEPI->setOperand(0, GEPI);
    6497             :     ConstantInt *UGEPIIdx = cast<ConstantInt>(UGEPI->getOperand(1));
    6498             :     Constant *NewUGEPIIdx =
    6499           3 :         ConstantInt::get(GEPIIdx->getType(),
    6500           3 :                          UGEPIIdx->getValue() - GEPIIdx->getValue());
    6501             :     UGEPI->setOperand(1, NewUGEPIIdx);
    6502             :     // If GEPI is not inbounds but UGEPI is inbounds, change UGEPI to not
    6503             :     // inbounds to avoid UB.
    6504           3 :     if (!GEPI->isInBounds()) {
    6505           3 :       UGEPI->setIsInBounds(false);
    6506             :     }
    6507             :   }
    6508             :   // After unmerging, verify that GEPIOp is actually only used in SrcBlock (not
    6509             :   // alive on IndirectBr edges).
    6510             :   assert(find_if(GEPIOp->users(), [&](User *Usr) {
    6511             :         return cast<Instruction>(Usr)->getParent() != SrcBlock;
    6512             :       }) == GEPIOp->users().end() && "GEPIOp is used outside SrcBlock");
    6513             :   return true;
    6514             : }
    6515             : 
    6516     5337332 : bool CodeGenPrepare::optimizeInst(Instruction *I, bool &ModifiedDT) {
    6517             :   // Bail out if we inserted the instruction to prevent optimizations from
    6518             :   // stepping on each other's toes.
    6519     5337332 :   if (InsertedInsts.count(I))
    6520             :     return false;
    6521             : 
    6522     5335662 :   if (PHINode *P = dyn_cast<PHINode>(I)) {
    6523             :     // It is possible for very late stage optimizations (such as SimplifyCFG)
    6524             :     // to introduce PHI nodes too late to be cleaned up.  If we detect such a
    6525             :     // trivial PHI, go ahead and zap it here.
    6526      360854 :     if (Value *V = SimplifyInstruction(P, {*DL, TLInfo})) {
    6527         455 :       P->replaceAllUsesWith(V);
    6528         455 :       P->eraseFromParent();
    6529             :       ++NumPHIsElim;
    6530         455 :       return true;
    6531             :     }
    6532             :     return false;
    6533             :   }
    6534             : 
    6535             :   if (CastInst *CI = dyn_cast<CastInst>(I)) {
    6536             :     // If the source of the cast is a constant, then this should have
    6537             :     // already been constant folded.  The only reason NOT to constant fold
    6538             :     // it is if something (e.g. LSR) was careful to place the constant
    6539             :     // evaluation in a block other than then one that uses it (e.g. to hoist
    6540             :     // the address of globals out of a loop).  If this is the case, we don't
    6541             :     // want to forward-subst the cast.
    6542      503611 :     if (isa<Constant>(CI->getOperand(0)))
    6543             :       return false;
    6544             : 
    6545      500007 :     if (TLI && OptimizeNoopCopyExpression(CI, *TLI, *DL))
    6546             :       return true;
    6547             : 
    6548      931136 :     if (isa<ZExtInst>(I) || isa<SExtInst>(I)) {
    6549             :       /// Sink a zext or sext into its user blocks if the target type doesn't
    6550             :       /// fit in one register
    6551       45955 :       if (TLI &&
    6552       91906 :           TLI->getTypeAction(CI->getContext(),
    6553       45953 :                              TLI->getValueType(*DL, CI->getType())) ==
    6554             :               TargetLowering::TypeExpandInteger) {
    6555        3644 :         return SinkCast(CI);
    6556             :       } else {
    6557       42311 :         bool MadeChange = optimizeExt(I);
    6558       42311 :         return MadeChange | optimizeExtUses(I);
    6559             :       }
    6560             :     }
    6561             :     return false;
    6562             :   }
    6563             : 
    6564             :   if (CmpInst *CI = dyn_cast<CmpInst>(I))
    6565      153307 :     if (!TLI || !TLI->hasMultipleConditionRegisters())
    6566      145212 :       return OptimizeCmpExpression(CI, TLI);
    6567             : 
    6568             :   if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
    6569      914998 :     LI->setMetadata(LLVMContext::MD_invariant_group, nullptr);
    6570      914998 :     if (TLI) {
    6571      914971 :       bool Modified = optimizeLoadExt(LI);
    6572             :       unsigned AS = LI->getPointerAddressSpace();
    6573     1829942 :       Modified |= optimizeMemoryInst(I, I->getOperand(0), LI->getType(), AS);
    6574      914971 :       return Modified;
    6575             :     }
    6576             :     return false;
    6577             :   }
    6578             : 
    6579             :   if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
    6580      791345 :     if (TLI && splitMergedValStore(*SI, *DL, *TLI))
    6581             :       return true;
    6582      791330 :     SI->setMetadata(LLVMContext::MD_invariant_group, nullptr);
    6583      791330 :     if (TLI) {
    6584             :       unsigned AS = SI->getPointerAddressSpace();
    6585      791311 :       return optimizeMemoryInst(I, SI->getOperand(1),
    6586      791311 :                                 SI->getOperand(0)->getType(), AS);
    6587             :     }
    6588             :     return false;
    6589             :   }
    6590             : 
    6591             :   if (AtomicRMWInst *RMW = dyn_cast<AtomicRMWInst>(I)) {
    6592             :       unsigned AS = RMW->getPointerAddressSpace();
    6593        5272 :       return optimizeMemoryInst(I, RMW->getPointerOperand(),
    6594        5272 :                                 RMW->getType(), AS);
    6595             :   }
    6596             : 
    6597             :   if (AtomicCmpXchgInst *CmpX = dyn_cast<AtomicCmpXchgInst>(I)) {
    6598             :       unsigned AS = CmpX->getPointerAddressSpace();
    6599        1579 :       return optimizeMemoryInst(I, CmpX->getPointerOperand(),
    6600        1579 :                                 CmpX->getCompareOperand()->getType(), AS);
    6601             :   }
    6602             : 
    6603             :   BinaryOperator *BinOp = dyn_cast<BinaryOperator>(I);
    6604             : 
    6605      850192 :   if (BinOp && (BinOp->getOpcode() == Instruction::And) &&
    6606       30694 :       EnableAndCmpSinking && TLI)
    6607       30694 :     return sinkAndCmp0Expression(BinOp, *TLI, InsertedInsts);
    6608             : 
    6609     2762524 :   if (BinOp && (BinOp->getOpcode() == Instruction::AShr ||
    6610             :                 BinOp->getOpcode() == Instruction::LShr)) {
    6611             :     ConstantInt *CI = dyn_cast<ConstantInt>(BinOp->getOperand(1));
    6612       19081 :     if (TLI && CI && TLI->hasExtractBitsInsn())
    6613        1951 :       return OptimizeExtractBits(BinOp, CI, *TLI, *DL);
    6614             : 
    6615             :     return false;
    6616             :   }
    6617             : 
    6618             :   if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(I)) {
    6619      234571 :     if (GEPI->hasAllZeroIndices()) {
    6620             :       /// The GEP operand must be a pointer, so must its result -> BitCast
    6621       25292 :       Instruction *NC = new BitCastInst(GEPI->getOperand(0), GEPI->getType(),
    6622       50584 :                                         GEPI->getName(), GEPI);
    6623       25292 :       NC->setDebugLoc(GEPI->getDebugLoc());
    6624       25292 :       GEPI->replaceAllUsesWith(NC);
    6625       25292 :       GEPI->eraseFromParent();
    6626             :       ++NumGEPsElim;
    6627       25292 :       optimizeInst(NC, ModifiedDT);
    6628       25292 :       return true;
    6629             :     }
    6630      209279 :     if (tryUnmergingGEPsAcrossIndirectBr(GEPI, TTI)) {
    6631             :       return true;
    6632             :     }
    6633      209278 :     return false;
    6634             :   }
    6635             : 
    6636             :   if (CallInst *CI = dyn_cast<CallInst>(I))
    6637      666803 :     return optimizeCallInst(CI, ModifiedDT);
    6638             : 
    6639             :   if (SelectInst *SI = dyn_cast<SelectInst>(I))
    6640       37997 :     return optimizeSelectInst(SI);
    6641             : 
    6642             :   if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(I))
    6643       48026 :     return optimizeShuffleVectorInst(SVI);
    6644             : 
    6645             :   if (auto *Switch = dyn_cast<SwitchInst>(I))
    6646        2274 :     return optimizeSwitchInst(Switch);
    6647             : 
    6648     1753772 :   if (isa<ExtractElementInst>(I))
    6649       30205 :     return optimizeExtractElementInst(I);
    6650             : 
    6651             :   return false;
    6652             : }
    6653             : 
    6654             : /// Given an OR instruction, check to see if this is a bitreverse
    6655             : /// idiom. If so, insert the new intrinsic and return true.
    6656     5332172 : static bool makeBitReverse(Instruction &I, const DataLayout &DL,
    6657             :                            const TargetLowering &TLI) {
    6658    10664344 :   if (!I.getType()->isIntegerTy() ||
    6659     1518337 :       !TLI.isOperationLegalOrCustom(ISD::BITREVERSE,
    6660             :                                     TLI.getValueType(DL, I.getType(), true)))
    6661     5261439 :     return false;
    6662             : 
    6663             :   SmallVector<Instruction*, 4> Insts;
    6664       70733 :   if (!recognizeBSwapOrBitReverseIdiom(&I, false, true, Insts))
    6665             :     return false;
    6666           6 :   Instruction *LastInst = Insts.back();
    6667           6 :   I.replaceAllUsesWith(LastInst);
    6668           6 :   RecursivelyDeleteTriviallyDeadInstructions(&I);
    6669           6 :   return true;
    6670             : }
    6671             : 
    6672             : // In this pass we look for GEP and cast instructions that are used
    6673             : // across basic blocks and rewrite them to improve basic-block-at-a-time
    6674             : // selection.
    6675      640297 : bool CodeGenPrepare::optimizeBlock(BasicBlock &BB, bool &ModifiedDT) {
    6676             :   SunkAddrs.clear();
    6677             :   bool MadeChange = false;
    6678             : 
    6679      640297 :   CurInstIterator = BB.begin();
    6680     5952306 :   while (CurInstIterator != BB.end()) {
    6681     5312040 :     MadeChange |= optimizeInst(&*CurInstIterator++, ModifiedDT);
    6682     5312040 :     if (ModifiedDT)
    6683             :       return true;
    6684             :   }
    6685             : 
    6686             :   bool MadeBitReverse = true;
    6687     1280374 :   while (TLI && MadeBitReverse) {
    6688             :     MadeBitReverse = false;
    6689     5972274 :     for (auto &I : reverse(BB)) {
    6690     5332172 :       if (makeBitReverse(I, *DL, *TLI)) {
    6691             :         MadeBitReverse = MadeChange = true;
    6692           6 :         ModifiedDT = true;
    6693           6 :         break;
    6694             :       }
    6695             :     }
    6696             :   }
    6697      640266 :   MadeChange |= dupRetToEnableTailCallOpts(&BB);
    6698             : 
    6699      640266 :   return MadeChange;
    6700             : }
    6701             : 
    6702             : // llvm.dbg.value is far away from the value then iSel may not be able
    6703             : // handle it properly. iSel will drop llvm.dbg.value if it can not
    6704             : // find a node corresponding to the value.
    6705           0 : bool CodeGenPrepare::placeDbgValues(Function &F) {
    6706             :   bool MadeChange = false;
    6707           0 :   for (BasicBlock &BB : F) {
    6708             :     Instruction *PrevNonDbgInst = nullptr;
    6709           0 :     for (BasicBlock::iterator BI = BB.begin(), BE = BB.end(); BI != BE;) {
    6710             :       Instruction *Insn = &*BI++;
    6711             :       DbgValueInst *DVI = dyn_cast<DbgValueInst>(Insn);
    6712             :       // Leave dbg.values that refer to an alloca alone. These
    6713             :       // intrinsics describe the address of a variable (= the alloca)
    6714             :       // being taken.  They should not be moved next to the alloca
    6715             :       // (and to the beginning of the scope), but rather stay close to
    6716             :       // where said address is used.
    6717           0 :       if (!DVI || (DVI->getValue() && isa<AllocaInst>(DVI->getValue()))) {
    6718             :         PrevNonDbgInst = Insn;
    6719           0 :         continue;
    6720             :       }
    6721             : 
    6722             :       Instruction *VI = dyn_cast_or_null<Instruction>(DVI->getValue());
    6723           0 :       if (VI && VI != PrevNonDbgInst && !VI->isTerminator()) {
    6724             :         // If VI is a phi in a block with an EHPad terminator, we can't insert
    6725             :         // after it.
    6726           0 :         if (isa<PHINode>(VI) && VI->getParent()->getTerminator()->isEHPad())
    6727           0 :           continue;
    6728             :         LLVM_DEBUG(dbgs() << "Moving Debug Value before :\n"
    6729             :                           << *DVI << ' ' << *VI);
    6730           0 :         DVI->removeFromParent();
    6731           0 :         if (isa<PHINode>(VI))
    6732           0 :           DVI->insertBefore(&*VI->getParent()->getFirstInsertionPt());
    6733             :         else
    6734           0 :           DVI->insertAfter(VI);
    6735             :         MadeChange = true;
    6736             :         ++NumDbgValueMoved;
    6737             :       }
    6738             :     }
    6739             :   }
    6740           0 :   return MadeChange;
    6741             : }
    6742             : 
    6743             : /// Scale down both weights to fit into uint32_t.
    6744             : static void scaleWeights(uint64_t &NewTrue, uint64_t &NewFalse) {
    6745             :   uint64_t NewMax = (NewTrue > NewFalse) ? NewTrue : NewFalse;
    6746             :   uint32_t Scale = (NewMax / std::numeric_limits<uint32_t>::max()) + 1;
    6747             :   NewTrue = NewTrue / Scale;
    6748             :   NewFalse = NewFalse / Scale;
    6749             : }
    6750             : 
    6751             : /// Some targets prefer to split a conditional branch like:
    6752             : /// \code
    6753             : ///   %0 = icmp ne i32 %a, 0
    6754             : ///   %1 = icmp ne i32 %b, 0
    6755             : ///   %or.cond = or i1 %0, %1
    6756             : ///   br i1 %or.cond, label %TrueBB, label %FalseBB
    6757             : /// \endcode
    6758             : /// into multiple branch instructions like:
    6759             : /// \code
    6760             : ///   bb1:
    6761             : ///     %0 = icmp ne i32 %a, 0
    6762             : ///     br i1 %0, label %TrueBB, label %bb2
    6763             : ///   bb2:
    6764             : ///     %1 = icmp ne i32 %b, 0
    6765             : ///     br i1 %1, label %TrueBB, label %FalseBB
    6766             : /// \endcode
    6767             : /// This usually allows instruction selection to do even further optimizations
    6768             : /// and combine the compare with the branch instruction. Currently this is
    6769             : /// applied for targets which have "cheap" jump instructions.
    6770             : ///
    6771             : /// FIXME: Remove the (equivalent?) implementation in SelectionDAG.
    6772             : ///
    6773      198465 : bool CodeGenPrepare::splitBranchCondition(Function &F) {
    6774      198465 :   if (!TM || !TM->Options.EnableFastISel || !TLI || TLI->isJumpExpensive())
    6775             :     return false;
    6776             : 
    6777             :   bool MadeChange = false;
    6778       16336 :   for (auto &BB : F) {
    6779             :     // Does this BB end with the following?
    6780             :     //   %cond1 = icmp|fcmp|binary instruction ...
    6781             :     //   %cond2 = icmp|fcmp|binary instruction ...
    6782             :     //   %cond.or = or|and i1 %cond1, cond2
    6783             :     //   br i1 %cond.or label %dest1, label %dest2"
    6784             :     BinaryOperator *LogicOp;
    6785             :     BasicBlock *TBB, *FBB;
    6786        8358 :     if (!match(BB.getTerminator(), m_Br(m_OneUse(m_BinOp(LogicOp)), TBB, FBB)))
    6787        8355 :       continue;
    6788             : 
    6789             :     auto *Br1 = cast<BranchInst>(BB.getTerminator());
    6790          10 :     if (Br1->getMetadata(LLVMContext::MD_unpredictable))
    6791             :       continue;
    6792             : 
    6793             :     unsigned Opc;
    6794             :     Value *Cond1, *Cond2;
    6795           4 :     if (match(LogicOp, m_And(m_OneUse(m_Value(Cond1)),
    6796           4 :                              m_OneUse(m_Value(Cond2)))))
    6797             :       Opc = Instruction::And;
    6798           2 :     else if (match(LogicOp, m_Or(m_OneUse(m_Value(Cond1)),
    6799           2 :                                  m_OneUse(m_Value(Cond2)))))
    6800             :       Opc = Instruction::Or;
    6801             :     else
    6802             :       continue;
    6803             : 
    6804           3 :     if (!match(Cond1, m_CombineOr(m_Cmp(), m_BinOp())) ||
    6805           3 :         !match(Cond2, m_CombineOr(m_Cmp(), m_BinOp()))   )
    6806           0 :       continue;
    6807             : 
    6808             :     LLVM_DEBUG(dbgs() << "Before branch condition splitting\n"; BB.dump());
    6809             : 
    6810             :     // Create a new BB.
    6811             :     auto TmpBB =
    6812           3 :         BasicBlock::Create(BB.getContext(), BB.getName() + ".cond.split",
    6813             :                            BB.getParent(), BB.getNextNode());
    6814             : 
    6815             :     // Update original basic block by using the first condition directly by the
    6816             :     // branch instruction and removing the no longer needed and/or instruction.
    6817           3 :     Br1->setCondition(Cond1);
    6818           3 :     LogicOp->eraseFromParent();
    6819             : 
    6820             :     // Depending on the condition we have to either replace the true or the
    6821             :     // false successor of the original branch instruction.
    6822           3 :     if (Opc == Instruction::And)
    6823             :       Br1->setSuccessor(0, TmpBB);
    6824             :     else
    6825             :       Br1->setSuccessor(1, TmpBB);
    6826             : 
    6827             :     // Fill in the new basic block.
    6828           3 :     auto *Br2 = IRBuilder<>(TmpBB).CreateCondBr(Cond2, TBB, FBB);
    6829           3 :     if (auto *I = dyn_cast<Instruction>(Cond2)) {
    6830           3 :       I->removeFromParent();
    6831           3 :       I->insertBefore(Br2);
    6832             :     }
    6833             : 
    6834             :     // Update PHI nodes in both successors. The original BB needs to be
    6835             :     // replaced in one successor's PHI nodes, because the branch comes now from
    6836             :     // the newly generated BB (NewBB). In the other successor we need to add one
    6837             :     // incoming edge to the PHI nodes, because both branch instructions target
    6838             :     // now the same successor. Depending on the original branch condition
    6839             :     // (and/or) we have to swap the successors (TrueDest, FalseDest), so that
    6840             :     // we perform the correct update for the PHI nodes.
    6841             :     // This doesn't change the successor order of the just created branch
    6842             :     // instruction (or any other instruction).
    6843           3 :     if (Opc == Instruction::Or)
    6844             :       std::swap(TBB, FBB);
    6845             : 
    6846             :     // Replace the old BB with the new BB.
    6847           6 :     for (PHINode &PN : TBB->phis()) {
    6848             :       int i;
    6849           0 :       while ((i = PN.getBasicBlockIndex(&BB)) >= 0)
    6850           0 :         PN.setIncomingBlock(i, TmpBB);
    6851             :     }
    6852             : 
    6853             :     // Add another incoming edge form the new BB.
    6854           6 :     for (PHINode &PN : FBB->phis()) {
    6855           0 :       auto *Val = PN.getIncomingValueForBlock(&BB);
    6856           0 :       PN.addIncoming(Val, TmpBB);
    6857             :     }
    6858             : 
    6859             :     // Update the branch weights (from SelectionDAGBuilder::
    6860             :     // FindMergedConditions).
    6861           3 :     if (Opc == Instruction::Or) {
    6862             :       // Codegen X | Y as:
    6863             :       // BB1:
    6864             :       //   jmp_if_X TBB
    6865             :       //   jmp TmpBB
    6866             :       // TmpBB:
    6867             :       //   jmp_if_Y TBB
    6868             :       //   jmp FBB
    6869             :       //
    6870             : 
    6871             :       // We have flexibility in setting Prob for BB1 and Prob for NewBB.
    6872             :       // The requirement is that
    6873             :       //   TrueProb for BB1 + (FalseProb for BB1 * TrueProb for TmpBB)
    6874             :       //     = TrueProb for original BB.
    6875             :       // Assuming the original weights are A and B, one choice is to set BB1's
    6876             :       // weights to A and A+2B, and set TmpBB's weights to A and 2B. This choice
    6877             :       // assumes that
    6878             :       //   TrueProb for BB1 == FalseProb for BB1 * TrueProb for TmpBB.
    6879             :       // Another choice is to assume TrueProb for BB1 equals to TrueProb for
    6880             :       // TmpBB, but the math is more complicated.
    6881             :       uint64_t TrueWeight, FalseWeight;
    6882           1 :       if (Br1->extractProfMetadata(TrueWeight, FalseWeight)) {
    6883             :         uint64_t NewTrueWeight = TrueWeight;
    6884             :         uint64_t NewFalseWeight = TrueWeight + 2 * FalseWeight;
    6885             :         scaleWeights(NewTrueWeight, NewFalseWeight);
    6886           1 :         Br1->setMetadata(LLVMContext::MD_prof, MDBuilder(Br1->getContext())
    6887             :                          .createBranchWeights(TrueWeight, FalseWeight));
    6888             : 
    6889             :         NewTrueWeight = TrueWeight;
    6890             :         NewFalseWeight = 2 * FalseWeight;
    6891             :         scaleWeights(NewTrueWeight, NewFalseWeight);
    6892           1 :         Br2->setMetadata(LLVMContext::MD_prof, MDBuilder(Br2->getContext())
    6893             :                          .createBranchWeights(TrueWeight, FalseWeight));
    6894             :       }
    6895             :     } else {
    6896             :       // Codegen X & Y as:
    6897             :       // BB1:
    6898             :       //   jmp_if_X TmpBB
    6899             :       //   jmp FBB
    6900             :       // TmpBB:
    6901             :       //   jmp_if_Y TBB
    6902             :       //   jmp FBB
    6903             :       //
    6904             :       //  This requires creation of TmpBB after CurBB.
    6905             : 
    6906             :       // We have flexibility in setting Prob for BB1 and Prob for TmpBB.
    6907             :       // The requirement is that
    6908             :       //   FalseProb for BB1 + (TrueProb for BB1 * FalseProb for TmpBB)
    6909             :       //     = FalseProb for original BB.
    6910             :       // Assuming the original weights are A and B, one choice is to set BB1's
    6911             :       // weights to 2A+B and B, and set TmpBB's weights to 2A and B. This choice
    6912             :       // assumes that
    6913             :       //   FalseProb for BB1 == TrueProb for BB1 * FalseProb for TmpBB.
    6914             :       uint64_t TrueWeight, FalseWeight;
    6915           2 :       if (Br1->extractProfMetadata(TrueWeight, FalseWeight)) {
    6916             :         uint64_t NewTrueWeight = 2 * TrueWeight + FalseWeight;
    6917             :         uint64_t NewFalseWeight = FalseWeight;
    6918             :         scaleWeights(NewTrueWeight, NewFalseWeight);
    6919           1 :         Br1->setMetadata(LLVMContext::MD_prof, MDBuilder(Br1->getContext())
    6920             :                          .createBranchWeights(TrueWeight, FalseWeight));
    6921             : 
    6922             :         NewTrueWeight = 2 * TrueWeight;
    6923             :         NewFalseWeight = FalseWeight;
    6924             :         scaleWeights(NewTrueWeight, NewFalseWeight);
    6925           1 :         Br2->setMetadata(LLVMContext::MD_prof, MDBuilder(Br2->getContext())
    6926             :                          .createBranchWeights(TrueWeight, FalseWeight));
    6927             :       }
    6928             :     }
    6929             : 
    6930             :     // Note: No point in getting fancy here, since the DT info is never
    6931             :     // available to CodeGenPrepare.
    6932           3 :     ModifiedDT = true;
    6933             : 
    6934             :     MadeChange = true;
    6935             : 
    6936             :     LLVM_DEBUG(dbgs() << "After branch condition splitting\n"; BB.dump();
    6937             :                TmpBB->dump());
    6938             :   }
    6939             :   return MadeChange;
    6940             : }

Generated by: LCOV version 1.13