Bug Summary

File:lib/Analysis/MemorySSA.cpp
Warning:line 1810, column 5
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name MemorySSA.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/lib/Analysis -I /build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/lib/Analysis -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp

1//===- MemorySSA.cpp - Memory SSA Builder ---------------------------------===//
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 file implements the MemorySSA class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Analysis/MemorySSA.h"
15#include "llvm/ADT/DenseMap.h"
16#include "llvm/ADT/DenseMapInfo.h"
17#include "llvm/ADT/DenseSet.h"
18#include "llvm/ADT/DepthFirstIterator.h"
19#include "llvm/ADT/Hashing.h"
20#include "llvm/ADT/None.h"
21#include "llvm/ADT/Optional.h"
22#include "llvm/ADT/STLExtras.h"
23#include "llvm/ADT/SmallPtrSet.h"
24#include "llvm/ADT/SmallVector.h"
25#include "llvm/ADT/iterator.h"
26#include "llvm/ADT/iterator_range.h"
27#include "llvm/Analysis/AliasAnalysis.h"
28#include "llvm/Analysis/IteratedDominanceFrontier.h"
29#include "llvm/Analysis/MemoryLocation.h"
30#include "llvm/Config/llvm-config.h"
31#include "llvm/IR/AssemblyAnnotationWriter.h"
32#include "llvm/IR/BasicBlock.h"
33#include "llvm/IR/CallSite.h"
34#include "llvm/IR/Dominators.h"
35#include "llvm/IR/Function.h"
36#include "llvm/IR/Instruction.h"
37#include "llvm/IR/Instructions.h"
38#include "llvm/IR/IntrinsicInst.h"
39#include "llvm/IR/Intrinsics.h"
40#include "llvm/IR/LLVMContext.h"
41#include "llvm/IR/PassManager.h"
42#include "llvm/IR/Use.h"
43#include "llvm/Pass.h"
44#include "llvm/Support/AtomicOrdering.h"
45#include "llvm/Support/Casting.h"
46#include "llvm/Support/CommandLine.h"
47#include "llvm/Support/Compiler.h"
48#include "llvm/Support/Debug.h"
49#include "llvm/Support/ErrorHandling.h"
50#include "llvm/Support/FormattedStream.h"
51#include "llvm/Support/raw_ostream.h"
52#include <algorithm>
53#include <cassert>
54#include <iterator>
55#include <memory>
56#include <utility>
57
58using namespace llvm;
59
60#define DEBUG_TYPE"memoryssa" "memoryssa"
61
62INITIALIZE_PASS_BEGIN(MemorySSAWrapperPass, "memoryssa", "Memory SSA", false,static void *initializeMemorySSAWrapperPassPassOnce(PassRegistry
&Registry) {
63 true)static void *initializeMemorySSAWrapperPassPassOnce(PassRegistry
&Registry) {
64INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)initializeDominatorTreeWrapperPassPass(Registry);
65INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)initializeAAResultsWrapperPassPass(Registry);
66INITIALIZE_PASS_END(MemorySSAWrapperPass, "memoryssa", "Memory SSA", false,PassInfo *PI = new PassInfo( "Memory SSA", "memoryssa", &
MemorySSAWrapperPass::ID, PassInfo::NormalCtor_t(callDefaultCtor
<MemorySSAWrapperPass>), false, true); Registry.registerPass
(*PI, true); return PI; } static llvm::once_flag InitializeMemorySSAWrapperPassPassFlag
; void llvm::initializeMemorySSAWrapperPassPass(PassRegistry &
Registry) { llvm::call_once(InitializeMemorySSAWrapperPassPassFlag
, initializeMemorySSAWrapperPassPassOnce, std::ref(Registry))
; }
67 true)PassInfo *PI = new PassInfo( "Memory SSA", "memoryssa", &
MemorySSAWrapperPass::ID, PassInfo::NormalCtor_t(callDefaultCtor
<MemorySSAWrapperPass>), false, true); Registry.registerPass
(*PI, true); return PI; } static llvm::once_flag InitializeMemorySSAWrapperPassPassFlag
; void llvm::initializeMemorySSAWrapperPassPass(PassRegistry &
Registry) { llvm::call_once(InitializeMemorySSAWrapperPassPassFlag
, initializeMemorySSAWrapperPassPassOnce, std::ref(Registry))
; }
68
69INITIALIZE_PASS_BEGIN(MemorySSAPrinterLegacyPass, "print-memoryssa",static void *initializeMemorySSAPrinterLegacyPassPassOnce(PassRegistry
&Registry) {
70 "Memory SSA Printer", false, false)static void *initializeMemorySSAPrinterLegacyPassPassOnce(PassRegistry
&Registry) {
71INITIALIZE_PASS_DEPENDENCY(MemorySSAWrapperPass)initializeMemorySSAWrapperPassPass(Registry);
72INITIALIZE_PASS_END(MemorySSAPrinterLegacyPass, "print-memoryssa",PassInfo *PI = new PassInfo( "Memory SSA Printer", "print-memoryssa"
, &MemorySSAPrinterLegacyPass::ID, PassInfo::NormalCtor_t
(callDefaultCtor<MemorySSAPrinterLegacyPass>), false, false
); Registry.registerPass(*PI, true); return PI; } static llvm
::once_flag InitializeMemorySSAPrinterLegacyPassPassFlag; void
llvm::initializeMemorySSAPrinterLegacyPassPass(PassRegistry &
Registry) { llvm::call_once(InitializeMemorySSAPrinterLegacyPassPassFlag
, initializeMemorySSAPrinterLegacyPassPassOnce, std::ref(Registry
)); }
73 "Memory SSA Printer", false, false)PassInfo *PI = new PassInfo( "Memory SSA Printer", "print-memoryssa"
, &MemorySSAPrinterLegacyPass::ID, PassInfo::NormalCtor_t
(callDefaultCtor<MemorySSAPrinterLegacyPass>), false, false
); Registry.registerPass(*PI, true); return PI; } static llvm
::once_flag InitializeMemorySSAPrinterLegacyPassPassFlag; void
llvm::initializeMemorySSAPrinterLegacyPassPass(PassRegistry &
Registry) { llvm::call_once(InitializeMemorySSAPrinterLegacyPassPassFlag
, initializeMemorySSAPrinterLegacyPassPassOnce, std::ref(Registry
)); }
74
75static cl::opt<unsigned> MaxCheckLimit(
76 "memssa-check-limit", cl::Hidden, cl::init(100),
77 cl::desc("The maximum number of stores/phis MemorySSA"
78 "will consider trying to walk past (default = 100)"));
79
80// Always verify MemorySSA if expensive checking is enabled.
81#ifdef EXPENSIVE_CHECKS
82bool llvm::VerifyMemorySSA = true;
83#else
84bool llvm::VerifyMemorySSA = false;
85#endif
86static cl::opt<bool, true>
87 VerifyMemorySSAX("verify-memoryssa", cl::location(VerifyMemorySSA),
88 cl::Hidden, cl::desc("Enable verification of MemorySSA."));
89
90namespace llvm {
91
92/// An assembly annotator class to print Memory SSA information in
93/// comments.
94class MemorySSAAnnotatedWriter : public AssemblyAnnotationWriter {
95 friend class MemorySSA;
96
97 const MemorySSA *MSSA;
98
99public:
100 MemorySSAAnnotatedWriter(const MemorySSA *M) : MSSA(M) {}
101
102 void emitBasicBlockStartAnnot(const BasicBlock *BB,
103 formatted_raw_ostream &OS) override {
104 if (MemoryAccess *MA = MSSA->getMemoryAccess(BB))
105 OS << "; " << *MA << "\n";
106 }
107
108 void emitInstructionAnnot(const Instruction *I,
109 formatted_raw_ostream &OS) override {
110 if (MemoryAccess *MA = MSSA->getMemoryAccess(I))
111 OS << "; " << *MA << "\n";
112 }
113};
114
115} // end namespace llvm
116
117namespace {
118
119/// Our current alias analysis API differentiates heavily between calls and
120/// non-calls, and functions called on one usually assert on the other.
121/// This class encapsulates the distinction to simplify other code that wants
122/// "Memory affecting instructions and related data" to use as a key.
123/// For example, this class is used as a densemap key in the use optimizer.
124class MemoryLocOrCall {
125public:
126 bool IsCall = false;
127
128 MemoryLocOrCall(MemoryUseOrDef *MUD)
129 : MemoryLocOrCall(MUD->getMemoryInst()) {}
130 MemoryLocOrCall(const MemoryUseOrDef *MUD)
131 : MemoryLocOrCall(MUD->getMemoryInst()) {}
132
133 MemoryLocOrCall(Instruction *Inst) {
134 if (ImmutableCallSite(Inst)) {
135 IsCall = true;
136 CS = ImmutableCallSite(Inst);
137 } else {
138 IsCall = false;
139 // There is no such thing as a memorylocation for a fence inst, and it is
140 // unique in that regard.
141 if (!isa<FenceInst>(Inst))
142 Loc = MemoryLocation::get(Inst);
143 }
144 }
145
146 explicit MemoryLocOrCall(const MemoryLocation &Loc) : Loc(Loc) {}
147
148 ImmutableCallSite getCS() const {
149 assert(IsCall)((IsCall) ? static_cast<void> (0) : __assert_fail ("IsCall"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 149, __PRETTY_FUNCTION__))
;
150 return CS;
151 }
152
153 MemoryLocation getLoc() const {
154 assert(!IsCall)((!IsCall) ? static_cast<void> (0) : __assert_fail ("!IsCall"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 154, __PRETTY_FUNCTION__))
;
155 return Loc;
156 }
157
158 bool operator==(const MemoryLocOrCall &Other) const {
159 if (IsCall != Other.IsCall)
160 return false;
161
162 if (!IsCall)
163 return Loc == Other.Loc;
164
165 if (CS.getCalledValue() != Other.CS.getCalledValue())
166 return false;
167
168 return CS.arg_size() == Other.CS.arg_size() &&
169 std::equal(CS.arg_begin(), CS.arg_end(), Other.CS.arg_begin());
170 }
171
172private:
173 union {
174 ImmutableCallSite CS;
175 MemoryLocation Loc;
176 };
177};
178
179} // end anonymous namespace
180
181namespace llvm {
182
183template <> struct DenseMapInfo<MemoryLocOrCall> {
184 static inline MemoryLocOrCall getEmptyKey() {
185 return MemoryLocOrCall(DenseMapInfo<MemoryLocation>::getEmptyKey());
186 }
187
188 static inline MemoryLocOrCall getTombstoneKey() {
189 return MemoryLocOrCall(DenseMapInfo<MemoryLocation>::getTombstoneKey());
190 }
191
192 static unsigned getHashValue(const MemoryLocOrCall &MLOC) {
193 if (!MLOC.IsCall)
194 return hash_combine(
195 MLOC.IsCall,
196 DenseMapInfo<MemoryLocation>::getHashValue(MLOC.getLoc()));
197
198 hash_code hash =
199 hash_combine(MLOC.IsCall, DenseMapInfo<const Value *>::getHashValue(
200 MLOC.getCS().getCalledValue()));
201
202 for (const Value *Arg : MLOC.getCS().args())
203 hash = hash_combine(hash, DenseMapInfo<const Value *>::getHashValue(Arg));
204 return hash;
205 }
206
207 static bool isEqual(const MemoryLocOrCall &LHS, const MemoryLocOrCall &RHS) {
208 return LHS == RHS;
209 }
210};
211
212} // end namespace llvm
213
214/// This does one-way checks to see if Use could theoretically be hoisted above
215/// MayClobber. This will not check the other way around.
216///
217/// This assumes that, for the purposes of MemorySSA, Use comes directly after
218/// MayClobber, with no potentially clobbering operations in between them.
219/// (Where potentially clobbering ops are memory barriers, aliased stores, etc.)
220static bool areLoadsReorderable(const LoadInst *Use,
221 const LoadInst *MayClobber) {
222 bool VolatileUse = Use->isVolatile();
223 bool VolatileClobber = MayClobber->isVolatile();
224 // Volatile operations may never be reordered with other volatile operations.
225 if (VolatileUse && VolatileClobber)
226 return false;
227 // Otherwise, volatile doesn't matter here. From the language reference:
228 // 'optimizers may change the order of volatile operations relative to
229 // non-volatile operations.'"
230
231 // If a load is seq_cst, it cannot be moved above other loads. If its ordering
232 // is weaker, it can be moved above other loads. We just need to be sure that
233 // MayClobber isn't an acquire load, because loads can't be moved above
234 // acquire loads.
235 //
236 // Note that this explicitly *does* allow the free reordering of monotonic (or
237 // weaker) loads of the same address.
238 bool SeqCstUse = Use->getOrdering() == AtomicOrdering::SequentiallyConsistent;
239 bool MayClobberIsAcquire = isAtLeastOrStrongerThan(MayClobber->getOrdering(),
240 AtomicOrdering::Acquire);
241 return !(SeqCstUse || MayClobberIsAcquire);
242}
243
244namespace {
245
246struct ClobberAlias {
247 bool IsClobber;
248 Optional<AliasResult> AR;
249};
250
251} // end anonymous namespace
252
253// Return a pair of {IsClobber (bool), AR (AliasResult)}. It relies on AR being
254// ignored if IsClobber = false.
255static ClobberAlias instructionClobbersQuery(const MemoryDef *MD,
256 const MemoryLocation &UseLoc,
257 const Instruction *UseInst,
258 AliasAnalysis &AA) {
259 Instruction *DefInst = MD->getMemoryInst();
260 assert(DefInst && "Defining instruction not actually an instruction")((DefInst && "Defining instruction not actually an instruction"
) ? static_cast<void> (0) : __assert_fail ("DefInst && \"Defining instruction not actually an instruction\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 260, __PRETTY_FUNCTION__))
;
261 ImmutableCallSite UseCS(UseInst);
262 Optional<AliasResult> AR;
263
264 if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(DefInst)) {
265 // These intrinsics will show up as affecting memory, but they are just
266 // markers, mostly.
267 //
268 // FIXME: We probably don't actually want MemorySSA to model these at all
269 // (including creating MemoryAccesses for them): we just end up inventing
270 // clobbers where they don't really exist at all. Please see D43269 for
271 // context.
272 switch (II->getIntrinsicID()) {
273 case Intrinsic::lifetime_start:
274 if (UseCS)
275 return {false, NoAlias};
276 AR = AA.alias(MemoryLocation(II->getArgOperand(1)), UseLoc);
277 return {AR != NoAlias, AR};
278 case Intrinsic::lifetime_end:
279 case Intrinsic::invariant_start:
280 case Intrinsic::invariant_end:
281 case Intrinsic::assume:
282 return {false, NoAlias};
283 default:
284 break;
285 }
286 }
287
288 if (UseCS) {
289 ModRefInfo I = AA.getModRefInfo(DefInst, UseCS);
290 AR = isMustSet(I) ? MustAlias : MayAlias;
291 return {isModOrRefSet(I), AR};
292 }
293
294 if (auto *DefLoad = dyn_cast<LoadInst>(DefInst))
295 if (auto *UseLoad = dyn_cast<LoadInst>(UseInst))
296 return {!areLoadsReorderable(UseLoad, DefLoad), MayAlias};
297
298 ModRefInfo I = AA.getModRefInfo(DefInst, UseLoc);
299 AR = isMustSet(I) ? MustAlias : MayAlias;
300 return {isModSet(I), AR};
301}
302
303static ClobberAlias instructionClobbersQuery(MemoryDef *MD,
304 const MemoryUseOrDef *MU,
305 const MemoryLocOrCall &UseMLOC,
306 AliasAnalysis &AA) {
307 // FIXME: This is a temporary hack to allow a single instructionClobbersQuery
308 // to exist while MemoryLocOrCall is pushed through places.
309 if (UseMLOC.IsCall)
310 return instructionClobbersQuery(MD, MemoryLocation(), MU->getMemoryInst(),
311 AA);
312 return instructionClobbersQuery(MD, UseMLOC.getLoc(), MU->getMemoryInst(),
313 AA);
314}
315
316// Return true when MD may alias MU, return false otherwise.
317bool MemorySSAUtil::defClobbersUseOrDef(MemoryDef *MD, const MemoryUseOrDef *MU,
318 AliasAnalysis &AA) {
319 return instructionClobbersQuery(MD, MU, MemoryLocOrCall(MU), AA).IsClobber;
320}
321
322namespace {
323
324struct UpwardsMemoryQuery {
325 // True if our original query started off as a call
326 bool IsCall = false;
327 // The pointer location we started the query with. This will be empty if
328 // IsCall is true.
329 MemoryLocation StartingLoc;
330 // This is the instruction we were querying about.
331 const Instruction *Inst = nullptr;
332 // The MemoryAccess we actually got called with, used to test local domination
333 const MemoryAccess *OriginalAccess = nullptr;
334 Optional<AliasResult> AR = MayAlias;
335
336 UpwardsMemoryQuery() = default;
337
338 UpwardsMemoryQuery(const Instruction *Inst, const MemoryAccess *Access)
339 : IsCall(ImmutableCallSite(Inst)), Inst(Inst), OriginalAccess(Access) {
340 if (!IsCall)
341 StartingLoc = MemoryLocation::get(Inst);
342 }
343};
344
345} // end anonymous namespace
346
347static bool lifetimeEndsAt(MemoryDef *MD, const MemoryLocation &Loc,
348 AliasAnalysis &AA) {
349 Instruction *Inst = MD->getMemoryInst();
350 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Inst)) {
351 switch (II->getIntrinsicID()) {
352 case Intrinsic::lifetime_end:
353 return AA.isMustAlias(MemoryLocation(II->getArgOperand(1)), Loc);
354 default:
355 return false;
356 }
357 }
358 return false;
359}
360
361static bool isUseTriviallyOptimizableToLiveOnEntry(AliasAnalysis &AA,
362 const Instruction *I) {
363 // If the memory can't be changed, then loads of the memory can't be
364 // clobbered.
365 return isa<LoadInst>(I) && (I->getMetadata(LLVMContext::MD_invariant_load) ||
366 AA.pointsToConstantMemory(cast<LoadInst>(I)->
367 getPointerOperand()));
368}
369
370/// Verifies that `Start` is clobbered by `ClobberAt`, and that nothing
371/// inbetween `Start` and `ClobberAt` can clobbers `Start`.
372///
373/// This is meant to be as simple and self-contained as possible. Because it
374/// uses no cache, etc., it can be relatively expensive.
375///
376/// \param Start The MemoryAccess that we want to walk from.
377/// \param ClobberAt A clobber for Start.
378/// \param StartLoc The MemoryLocation for Start.
379/// \param MSSA The MemorySSA instance that Start and ClobberAt belong to.
380/// \param Query The UpwardsMemoryQuery we used for our search.
381/// \param AA The AliasAnalysis we used for our search.
382/// \param AllowImpreciseClobber Always false, unless we do relaxed verify.
383static void
384checkClobberSanity(const MemoryAccess *Start, MemoryAccess *ClobberAt,
385 const MemoryLocation &StartLoc, const MemorySSA &MSSA,
386 const UpwardsMemoryQuery &Query, AliasAnalysis &AA,
387 bool AllowImpreciseClobber = false) {
388 assert(MSSA.dominates(ClobberAt, Start) && "Clobber doesn't dominate start?")((MSSA.dominates(ClobberAt, Start) && "Clobber doesn't dominate start?"
) ? static_cast<void> (0) : __assert_fail ("MSSA.dominates(ClobberAt, Start) && \"Clobber doesn't dominate start?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 388, __PRETTY_FUNCTION__))
;
389
390 if (MSSA.isLiveOnEntryDef(Start)) {
391 assert(MSSA.isLiveOnEntryDef(ClobberAt) &&((MSSA.isLiveOnEntryDef(ClobberAt) && "liveOnEntry must clobber itself"
) ? static_cast<void> (0) : __assert_fail ("MSSA.isLiveOnEntryDef(ClobberAt) && \"liveOnEntry must clobber itself\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 392, __PRETTY_FUNCTION__))
392 "liveOnEntry must clobber itself")((MSSA.isLiveOnEntryDef(ClobberAt) && "liveOnEntry must clobber itself"
) ? static_cast<void> (0) : __assert_fail ("MSSA.isLiveOnEntryDef(ClobberAt) && \"liveOnEntry must clobber itself\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 392, __PRETTY_FUNCTION__))
;
393 return;
394 }
395
396 bool FoundClobber = false;
397 DenseSet<ConstMemoryAccessPair> VisitedPhis;
398 SmallVector<ConstMemoryAccessPair, 8> Worklist;
399 Worklist.emplace_back(Start, StartLoc);
400 // Walk all paths from Start to ClobberAt, while looking for clobbers. If one
401 // is found, complain.
402 while (!Worklist.empty()) {
403 auto MAP = Worklist.pop_back_val();
404 // All we care about is that nothing from Start to ClobberAt clobbers Start.
405 // We learn nothing from revisiting nodes.
406 if (!VisitedPhis.insert(MAP).second)
407 continue;
408
409 for (const auto *MA : def_chain(MAP.first)) {
410 if (MA == ClobberAt) {
411 if (const auto *MD = dyn_cast<MemoryDef>(MA)) {
412 // instructionClobbersQuery isn't essentially free, so don't use `|=`,
413 // since it won't let us short-circuit.
414 //
415 // Also, note that this can't be hoisted out of the `Worklist` loop,
416 // since MD may only act as a clobber for 1 of N MemoryLocations.
417 FoundClobber = FoundClobber || MSSA.isLiveOnEntryDef(MD);
418 if (!FoundClobber) {
419 ClobberAlias CA =
420 instructionClobbersQuery(MD, MAP.second, Query.Inst, AA);
421 if (CA.IsClobber) {
422 FoundClobber = true;
423 // Not used: CA.AR;
424 }
425 }
426 }
427 break;
428 }
429
430 // We should never hit liveOnEntry, unless it's the clobber.
431 assert(!MSSA.isLiveOnEntryDef(MA) && "Hit liveOnEntry before clobber?")((!MSSA.isLiveOnEntryDef(MA) && "Hit liveOnEntry before clobber?"
) ? static_cast<void> (0) : __assert_fail ("!MSSA.isLiveOnEntryDef(MA) && \"Hit liveOnEntry before clobber?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 431, __PRETTY_FUNCTION__))
;
432
433 if (const auto *MD = dyn_cast<MemoryDef>(MA)) {
434 // If Start is a Def, skip self.
435 if (MD == Start)
436 continue;
437
438 assert(!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA)((!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA) .
IsClobber && "Found clobber before reaching ClobberAt!"
) ? static_cast<void> (0) : __assert_fail ("!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA) .IsClobber && \"Found clobber before reaching ClobberAt!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 440, __PRETTY_FUNCTION__))
439 .IsClobber &&((!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA) .
IsClobber && "Found clobber before reaching ClobberAt!"
) ? static_cast<void> (0) : __assert_fail ("!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA) .IsClobber && \"Found clobber before reaching ClobberAt!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 440, __PRETTY_FUNCTION__))
440 "Found clobber before reaching ClobberAt!")((!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA) .
IsClobber && "Found clobber before reaching ClobberAt!"
) ? static_cast<void> (0) : __assert_fail ("!instructionClobbersQuery(MD, MAP.second, Query.Inst, AA) .IsClobber && \"Found clobber before reaching ClobberAt!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 440, __PRETTY_FUNCTION__))
;
441 continue;
442 }
443
444 if (const auto *MU = dyn_cast<MemoryUse>(MA)) {
445 (void)MU;
446 assert (MU == Start &&((MU == Start && "Can only find use in def chain if Start is a use"
) ? static_cast<void> (0) : __assert_fail ("MU == Start && \"Can only find use in def chain if Start is a use\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 447, __PRETTY_FUNCTION__))
447 "Can only find use in def chain if Start is a use")((MU == Start && "Can only find use in def chain if Start is a use"
) ? static_cast<void> (0) : __assert_fail ("MU == Start && \"Can only find use in def chain if Start is a use\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 447, __PRETTY_FUNCTION__))
;
448 continue;
449 }
450
451 assert(isa<MemoryPhi>(MA))((isa<MemoryPhi>(MA)) ? static_cast<void> (0) : __assert_fail
("isa<MemoryPhi>(MA)", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 451, __PRETTY_FUNCTION__))
;
452 Worklist.append(
453 upward_defs_begin({const_cast<MemoryAccess *>(MA), MAP.second}),
454 upward_defs_end());
455 }
456 }
457
458 // If the verify is done following an optimization, it's possible that
459 // ClobberAt was a conservative clobbering, that we can now infer is not a
460 // true clobbering access. Don't fail the verify if that's the case.
461 // We do have accesses that claim they're optimized, but could be optimized
462 // further. Updating all these can be expensive, so allow it for now (FIXME).
463 if (AllowImpreciseClobber)
464 return;
465
466 // If ClobberAt is a MemoryPhi, we can assume something above it acted as a
467 // clobber. Otherwise, `ClobberAt` should've acted as a clobber at some point.
468 assert((isa<MemoryPhi>(ClobberAt) || FoundClobber) &&(((isa<MemoryPhi>(ClobberAt) || FoundClobber) &&
"ClobberAt never acted as a clobber") ? static_cast<void>
(0) : __assert_fail ("(isa<MemoryPhi>(ClobberAt) || FoundClobber) && \"ClobberAt never acted as a clobber\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 469, __PRETTY_FUNCTION__))
469 "ClobberAt never acted as a clobber")(((isa<MemoryPhi>(ClobberAt) || FoundClobber) &&
"ClobberAt never acted as a clobber") ? static_cast<void>
(0) : __assert_fail ("(isa<MemoryPhi>(ClobberAt) || FoundClobber) && \"ClobberAt never acted as a clobber\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 469, __PRETTY_FUNCTION__))
;
470}
471
472namespace {
473
474/// Our algorithm for walking (and trying to optimize) clobbers, all wrapped up
475/// in one class.
476class ClobberWalker {
477 /// Save a few bytes by using unsigned instead of size_t.
478 using ListIndex = unsigned;
479
480 /// Represents a span of contiguous MemoryDefs, potentially ending in a
481 /// MemoryPhi.
482 struct DefPath {
483 MemoryLocation Loc;
484 // Note that, because we always walk in reverse, Last will always dominate
485 // First. Also note that First and Last are inclusive.
486 MemoryAccess *First;
487 MemoryAccess *Last;
488 Optional<ListIndex> Previous;
489
490 DefPath(const MemoryLocation &Loc, MemoryAccess *First, MemoryAccess *Last,
491 Optional<ListIndex> Previous)
492 : Loc(Loc), First(First), Last(Last), Previous(Previous) {}
493
494 DefPath(const MemoryLocation &Loc, MemoryAccess *Init,
495 Optional<ListIndex> Previous)
496 : DefPath(Loc, Init, Init, Previous) {}
497 };
498
499 const MemorySSA &MSSA;
500 AliasAnalysis &AA;
501 DominatorTree &DT;
502 UpwardsMemoryQuery *Query;
503
504 // Phi optimization bookkeeping
505 SmallVector<DefPath, 32> Paths;
506 DenseSet<ConstMemoryAccessPair> VisitedPhis;
507
508 /// Find the nearest def or phi that `From` can legally be optimized to.
509 const MemoryAccess *getWalkTarget(const MemoryPhi *From) const {
510 assert(From->getNumOperands() && "Phi with no operands?")((From->getNumOperands() && "Phi with no operands?"
) ? static_cast<void> (0) : __assert_fail ("From->getNumOperands() && \"Phi with no operands?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 510, __PRETTY_FUNCTION__))
;
511
512 BasicBlock *BB = From->getBlock();
513 MemoryAccess *Result = MSSA.getLiveOnEntryDef();
514 DomTreeNode *Node = DT.getNode(BB);
515 while ((Node = Node->getIDom())) {
516 auto *Defs = MSSA.getBlockDefs(Node->getBlock());
517 if (Defs)
518 return &*Defs->rbegin();
519 }
520 return Result;
521 }
522
523 /// Result of calling walkToPhiOrClobber.
524 struct UpwardsWalkResult {
525 /// The "Result" of the walk. Either a clobber, the last thing we walked, or
526 /// both. Include alias info when clobber found.
527 MemoryAccess *Result;
528 bool IsKnownClobber;
529 Optional<AliasResult> AR;
530 };
531
532 /// Walk to the next Phi or Clobber in the def chain starting at Desc.Last.
533 /// This will update Desc.Last as it walks. It will (optionally) also stop at
534 /// StopAt.
535 ///
536 /// This does not test for whether StopAt is a clobber
537 UpwardsWalkResult
538 walkToPhiOrClobber(DefPath &Desc,
539 const MemoryAccess *StopAt = nullptr) const {
540 assert(!isa<MemoryUse>(Desc.Last) && "Uses don't exist in my world")((!isa<MemoryUse>(Desc.Last) && "Uses don't exist in my world"
) ? static_cast<void> (0) : __assert_fail ("!isa<MemoryUse>(Desc.Last) && \"Uses don't exist in my world\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 540, __PRETTY_FUNCTION__))
;
541
542 for (MemoryAccess *Current : def_chain(Desc.Last)) {
543 Desc.Last = Current;
544 if (Current == StopAt)
545 return {Current, false, MayAlias};
546
547 if (auto *MD = dyn_cast<MemoryDef>(Current)) {
548 if (MSSA.isLiveOnEntryDef(MD))
549 return {MD, true, MustAlias};
550 ClobberAlias CA =
551 instructionClobbersQuery(MD, Desc.Loc, Query->Inst, AA);
552 if (CA.IsClobber)
553 return {MD, true, CA.AR};
554 }
555 }
556
557 assert(isa<MemoryPhi>(Desc.Last) &&((isa<MemoryPhi>(Desc.Last) && "Ended at a non-clobber that's not a phi?"
) ? static_cast<void> (0) : __assert_fail ("isa<MemoryPhi>(Desc.Last) && \"Ended at a non-clobber that's not a phi?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 558, __PRETTY_FUNCTION__))
558 "Ended at a non-clobber that's not a phi?")((isa<MemoryPhi>(Desc.Last) && "Ended at a non-clobber that's not a phi?"
) ? static_cast<void> (0) : __assert_fail ("isa<MemoryPhi>(Desc.Last) && \"Ended at a non-clobber that's not a phi?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 558, __PRETTY_FUNCTION__))
;
559 return {Desc.Last, false, MayAlias};
560 }
561
562 void addSearches(MemoryPhi *Phi, SmallVectorImpl<ListIndex> &PausedSearches,
563 ListIndex PriorNode) {
564 auto UpwardDefs = make_range(upward_defs_begin({Phi, Paths[PriorNode].Loc}),
565 upward_defs_end());
566 for (const MemoryAccessPair &P : UpwardDefs) {
567 PausedSearches.push_back(Paths.size());
568 Paths.emplace_back(P.second, P.first, PriorNode);
569 }
570 }
571
572 /// Represents a search that terminated after finding a clobber. This clobber
573 /// may or may not be present in the path of defs from LastNode..SearchStart,
574 /// since it may have been retrieved from cache.
575 struct TerminatedPath {
576 MemoryAccess *Clobber;
577 ListIndex LastNode;
578 };
579
580 /// Get an access that keeps us from optimizing to the given phi.
581 ///
582 /// PausedSearches is an array of indices into the Paths array. Its incoming
583 /// value is the indices of searches that stopped at the last phi optimization
584 /// target. It's left in an unspecified state.
585 ///
586 /// If this returns None, NewPaused is a vector of searches that terminated
587 /// at StopWhere. Otherwise, NewPaused is left in an unspecified state.
588 Optional<TerminatedPath>
589 getBlockingAccess(const MemoryAccess *StopWhere,
590 SmallVectorImpl<ListIndex> &PausedSearches,
591 SmallVectorImpl<ListIndex> &NewPaused,
592 SmallVectorImpl<TerminatedPath> &Terminated) {
593 assert(!PausedSearches.empty() && "No searches to continue?")((!PausedSearches.empty() && "No searches to continue?"
) ? static_cast<void> (0) : __assert_fail ("!PausedSearches.empty() && \"No searches to continue?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 593, __PRETTY_FUNCTION__))
;
594
595 // BFS vs DFS really doesn't make a difference here, so just do a DFS with
596 // PausedSearches as our stack.
597 while (!PausedSearches.empty()) {
598 ListIndex PathIndex = PausedSearches.pop_back_val();
599 DefPath &Node = Paths[PathIndex];
600
601 // If we've already visited this path with this MemoryLocation, we don't
602 // need to do so again.
603 //
604 // NOTE: That we just drop these paths on the ground makes caching
605 // behavior sporadic. e.g. given a diamond:
606 // A
607 // B C
608 // D
609 //
610 // ...If we walk D, B, A, C, we'll only cache the result of phi
611 // optimization for A, B, and D; C will be skipped because it dies here.
612 // This arguably isn't the worst thing ever, since:
613 // - We generally query things in a top-down order, so if we got below D
614 // without needing cache entries for {C, MemLoc}, then chances are
615 // that those cache entries would end up ultimately unused.
616 // - We still cache things for A, so C only needs to walk up a bit.
617 // If this behavior becomes problematic, we can fix without a ton of extra
618 // work.
619 if (!VisitedPhis.insert({Node.Last, Node.Loc}).second)
620 continue;
621
622 UpwardsWalkResult Res = walkToPhiOrClobber(Node, /*StopAt=*/StopWhere);
623 if (Res.IsKnownClobber) {
624 assert(Res.Result != StopWhere)((Res.Result != StopWhere) ? static_cast<void> (0) : __assert_fail
("Res.Result != StopWhere", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 624, __PRETTY_FUNCTION__))
;
625 // If this wasn't a cache hit, we hit a clobber when walking. That's a
626 // failure.
627 TerminatedPath Term{Res.Result, PathIndex};
628 if (!MSSA.dominates(Res.Result, StopWhere))
629 return Term;
630
631 // Otherwise, it's a valid thing to potentially optimize to.
632 Terminated.push_back(Term);
633 continue;
634 }
635
636 if (Res.Result == StopWhere) {
637 // We've hit our target. Save this path off for if we want to continue
638 // walking.
639 NewPaused.push_back(PathIndex);
640 continue;
641 }
642
643 assert(!MSSA.isLiveOnEntryDef(Res.Result) && "liveOnEntry is a clobber")((!MSSA.isLiveOnEntryDef(Res.Result) && "liveOnEntry is a clobber"
) ? static_cast<void> (0) : __assert_fail ("!MSSA.isLiveOnEntryDef(Res.Result) && \"liveOnEntry is a clobber\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 643, __PRETTY_FUNCTION__))
;
644 addSearches(cast<MemoryPhi>(Res.Result), PausedSearches, PathIndex);
645 }
646
647 return None;
648 }
649
650 template <typename T, typename Walker>
651 struct generic_def_path_iterator
652 : public iterator_facade_base<generic_def_path_iterator<T, Walker>,
653 std::forward_iterator_tag, T *> {
654 generic_def_path_iterator() = default;
655 generic_def_path_iterator(Walker *W, ListIndex N) : W(W), N(N) {}
656
657 T &operator*() const { return curNode(); }
658
659 generic_def_path_iterator &operator++() {
660 N = curNode().Previous;
661 return *this;
662 }
663
664 bool operator==(const generic_def_path_iterator &O) const {
665 if (N.hasValue() != O.N.hasValue())
666 return false;
667 return !N.hasValue() || *N == *O.N;
668 }
669
670 private:
671 T &curNode() const { return W->Paths[*N]; }
672
673 Walker *W = nullptr;
674 Optional<ListIndex> N = None;
675 };
676
677 using def_path_iterator = generic_def_path_iterator<DefPath, ClobberWalker>;
678 using const_def_path_iterator =
679 generic_def_path_iterator<const DefPath, const ClobberWalker>;
680
681 iterator_range<def_path_iterator> def_path(ListIndex From) {
682 return make_range(def_path_iterator(this, From), def_path_iterator());
683 }
684
685 iterator_range<const_def_path_iterator> const_def_path(ListIndex From) const {
686 return make_range(const_def_path_iterator(this, From),
687 const_def_path_iterator());
688 }
689
690 struct OptznResult {
691 /// The path that contains our result.
692 TerminatedPath PrimaryClobber;
693 /// The paths that we can legally cache back from, but that aren't
694 /// necessarily the result of the Phi optimization.
695 SmallVector<TerminatedPath, 4> OtherClobbers;
696 };
697
698 ListIndex defPathIndex(const DefPath &N) const {
699 // The assert looks nicer if we don't need to do &N
700 const DefPath *NP = &N;
701 assert(!Paths.empty() && NP >= &Paths.front() && NP <= &Paths.back() &&((!Paths.empty() && NP >= &Paths.front() &&
NP <= &Paths.back() && "Out of bounds DefPath!"
) ? static_cast<void> (0) : __assert_fail ("!Paths.empty() && NP >= &Paths.front() && NP <= &Paths.back() && \"Out of bounds DefPath!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 702, __PRETTY_FUNCTION__))
702 "Out of bounds DefPath!")((!Paths.empty() && NP >= &Paths.front() &&
NP <= &Paths.back() && "Out of bounds DefPath!"
) ? static_cast<void> (0) : __assert_fail ("!Paths.empty() && NP >= &Paths.front() && NP <= &Paths.back() && \"Out of bounds DefPath!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 702, __PRETTY_FUNCTION__))
;
703 return NP - &Paths.front();
704 }
705
706 /// Try to optimize a phi as best as we can. Returns a SmallVector of Paths
707 /// that act as legal clobbers. Note that this won't return *all* clobbers.
708 ///
709 /// Phi optimization algorithm tl;dr:
710 /// - Find the earliest def/phi, A, we can optimize to
711 /// - Find if all paths from the starting memory access ultimately reach A
712 /// - If not, optimization isn't possible.
713 /// - Otherwise, walk from A to another clobber or phi, A'.
714 /// - If A' is a def, we're done.
715 /// - If A' is a phi, try to optimize it.
716 ///
717 /// A path is a series of {MemoryAccess, MemoryLocation} pairs. A path
718 /// terminates when a MemoryAccess that clobbers said MemoryLocation is found.
719 OptznResult tryOptimizePhi(MemoryPhi *Phi, MemoryAccess *Start,
720 const MemoryLocation &Loc) {
721 assert(Paths.empty() && VisitedPhis.empty() &&((Paths.empty() && VisitedPhis.empty() && "Reset the optimization state."
) ? static_cast<void> (0) : __assert_fail ("Paths.empty() && VisitedPhis.empty() && \"Reset the optimization state.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 722, __PRETTY_FUNCTION__))
722 "Reset the optimization state.")((Paths.empty() && VisitedPhis.empty() && "Reset the optimization state."
) ? static_cast<void> (0) : __assert_fail ("Paths.empty() && VisitedPhis.empty() && \"Reset the optimization state.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 722, __PRETTY_FUNCTION__))
;
723
724 Paths.emplace_back(Loc, Start, Phi, None);
725 // Stores how many "valid" optimization nodes we had prior to calling
726 // addSearches/getBlockingAccess. Necessary for caching if we had a blocker.
727 auto PriorPathsSize = Paths.size();
728
729 SmallVector<ListIndex, 16> PausedSearches;
730 SmallVector<ListIndex, 8> NewPaused;
731 SmallVector<TerminatedPath, 4> TerminatedPaths;
732
733 addSearches(Phi, PausedSearches, 0);
734
735 // Moves the TerminatedPath with the "most dominated" Clobber to the end of
736 // Paths.
737 auto MoveDominatedPathToEnd = [&](SmallVectorImpl<TerminatedPath> &Paths) {
738 assert(!Paths.empty() && "Need a path to move")((!Paths.empty() && "Need a path to move") ? static_cast
<void> (0) : __assert_fail ("!Paths.empty() && \"Need a path to move\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 738, __PRETTY_FUNCTION__))
;
739 auto Dom = Paths.begin();
740 for (auto I = std::next(Dom), E = Paths.end(); I != E; ++I)
741 if (!MSSA.dominates(I->Clobber, Dom->Clobber))
742 Dom = I;
743 auto Last = Paths.end() - 1;
744 if (Last != Dom)
745 std::iter_swap(Last, Dom);
746 };
747
748 MemoryPhi *Current = Phi;
749 while (true) {
750 assert(!MSSA.isLiveOnEntryDef(Current) &&((!MSSA.isLiveOnEntryDef(Current) && "liveOnEntry wasn't treated as a clobber?"
) ? static_cast<void> (0) : __assert_fail ("!MSSA.isLiveOnEntryDef(Current) && \"liveOnEntry wasn't treated as a clobber?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 751, __PRETTY_FUNCTION__))
751 "liveOnEntry wasn't treated as a clobber?")((!MSSA.isLiveOnEntryDef(Current) && "liveOnEntry wasn't treated as a clobber?"
) ? static_cast<void> (0) : __assert_fail ("!MSSA.isLiveOnEntryDef(Current) && \"liveOnEntry wasn't treated as a clobber?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 751, __PRETTY_FUNCTION__))
;
752
753 const auto *Target = getWalkTarget(Current);
754 // If a TerminatedPath doesn't dominate Target, then it wasn't a legal
755 // optimization for the prior phi.
756 assert(all_of(TerminatedPaths, [&](const TerminatedPath &P) {((all_of(TerminatedPaths, [&](const TerminatedPath &P
) { return MSSA.dominates(P.Clobber, Target); })) ? static_cast
<void> (0) : __assert_fail ("all_of(TerminatedPaths, [&](const TerminatedPath &P) { return MSSA.dominates(P.Clobber, Target); })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 758, __PRETTY_FUNCTION__))
757 return MSSA.dominates(P.Clobber, Target);((all_of(TerminatedPaths, [&](const TerminatedPath &P
) { return MSSA.dominates(P.Clobber, Target); })) ? static_cast
<void> (0) : __assert_fail ("all_of(TerminatedPaths, [&](const TerminatedPath &P) { return MSSA.dominates(P.Clobber, Target); })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 758, __PRETTY_FUNCTION__))
758 }))((all_of(TerminatedPaths, [&](const TerminatedPath &P
) { return MSSA.dominates(P.Clobber, Target); })) ? static_cast
<void> (0) : __assert_fail ("all_of(TerminatedPaths, [&](const TerminatedPath &P) { return MSSA.dominates(P.Clobber, Target); })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 758, __PRETTY_FUNCTION__))
;
759
760 // FIXME: This is broken, because the Blocker may be reported to be
761 // liveOnEntry, and we'll happily wait for that to disappear (read: never)
762 // For the moment, this is fine, since we do nothing with blocker info.
763 if (Optional<TerminatedPath> Blocker = getBlockingAccess(
764 Target, PausedSearches, NewPaused, TerminatedPaths)) {
765
766 // Find the node we started at. We can't search based on N->Last, since
767 // we may have gone around a loop with a different MemoryLocation.
768 auto Iter = find_if(def_path(Blocker->LastNode), [&](const DefPath &N) {
769 return defPathIndex(N) < PriorPathsSize;
770 });
771 assert(Iter != def_path_iterator())((Iter != def_path_iterator()) ? static_cast<void> (0) :
__assert_fail ("Iter != def_path_iterator()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 771, __PRETTY_FUNCTION__))
;
772
773 DefPath &CurNode = *Iter;
774 assert(CurNode.Last == Current)((CurNode.Last == Current) ? static_cast<void> (0) : __assert_fail
("CurNode.Last == Current", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 774, __PRETTY_FUNCTION__))
;
775
776 // Two things:
777 // A. We can't reliably cache all of NewPaused back. Consider a case
778 // where we have two paths in NewPaused; one of which can't optimize
779 // above this phi, whereas the other can. If we cache the second path
780 // back, we'll end up with suboptimal cache entries. We can handle
781 // cases like this a bit better when we either try to find all
782 // clobbers that block phi optimization, or when our cache starts
783 // supporting unfinished searches.
784 // B. We can't reliably cache TerminatedPaths back here without doing
785 // extra checks; consider a case like:
786 // T
787 // / \
788 // D C
789 // \ /
790 // S
791 // Where T is our target, C is a node with a clobber on it, D is a
792 // diamond (with a clobber *only* on the left or right node, N), and
793 // S is our start. Say we walk to D, through the node opposite N
794 // (read: ignoring the clobber), and see a cache entry in the top
795 // node of D. That cache entry gets put into TerminatedPaths. We then
796 // walk up to C (N is later in our worklist), find the clobber, and
797 // quit. If we append TerminatedPaths to OtherClobbers, we'll cache
798 // the bottom part of D to the cached clobber, ignoring the clobber
799 // in N. Again, this problem goes away if we start tracking all
800 // blockers for a given phi optimization.
801 TerminatedPath Result{CurNode.Last, defPathIndex(CurNode)};
802 return {Result, {}};
803 }
804
805 // If there's nothing left to search, then all paths led to valid clobbers
806 // that we got from our cache; pick the nearest to the start, and allow
807 // the rest to be cached back.
808 if (NewPaused.empty()) {
809 MoveDominatedPathToEnd(TerminatedPaths);
810 TerminatedPath Result = TerminatedPaths.pop_back_val();
811 return {Result, std::move(TerminatedPaths)};
812 }
813
814 MemoryAccess *DefChainEnd = nullptr;
815 SmallVector<TerminatedPath, 4> Clobbers;
816 for (ListIndex Paused : NewPaused) {
817 UpwardsWalkResult WR = walkToPhiOrClobber(Paths[Paused]);
818 if (WR.IsKnownClobber)
819 Clobbers.push_back({WR.Result, Paused});
820 else
821 // Micro-opt: If we hit the end of the chain, save it.
822 DefChainEnd = WR.Result;
823 }
824
825 if (!TerminatedPaths.empty()) {
826 // If we couldn't find the dominating phi/liveOnEntry in the above loop,
827 // do it now.
828 if (!DefChainEnd)
829 for (auto *MA : def_chain(const_cast<MemoryAccess *>(Target)))
830 DefChainEnd = MA;
831
832 // If any of the terminated paths don't dominate the phi we'll try to
833 // optimize, we need to figure out what they are and quit.
834 const BasicBlock *ChainBB = DefChainEnd->getBlock();
835 for (const TerminatedPath &TP : TerminatedPaths) {
836 // Because we know that DefChainEnd is as "high" as we can go, we
837 // don't need local dominance checks; BB dominance is sufficient.
838 if (DT.dominates(ChainBB, TP.Clobber->getBlock()))
839 Clobbers.push_back(TP);
840 }
841 }
842
843 // If we have clobbers in the def chain, find the one closest to Current
844 // and quit.
845 if (!Clobbers.empty()) {
846 MoveDominatedPathToEnd(Clobbers);
847 TerminatedPath Result = Clobbers.pop_back_val();
848 return {Result, std::move(Clobbers)};
849 }
850
851 assert(all_of(NewPaused,((all_of(NewPaused, [&](ListIndex I) { return Paths[I].Last
== DefChainEnd; })) ? static_cast<void> (0) : __assert_fail
("all_of(NewPaused, [&](ListIndex I) { return Paths[I].Last == DefChainEnd; })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 852, __PRETTY_FUNCTION__))
852 [&](ListIndex I) { return Paths[I].Last == DefChainEnd; }))((all_of(NewPaused, [&](ListIndex I) { return Paths[I].Last
== DefChainEnd; })) ? static_cast<void> (0) : __assert_fail
("all_of(NewPaused, [&](ListIndex I) { return Paths[I].Last == DefChainEnd; })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 852, __PRETTY_FUNCTION__))
;
853
854 // Because liveOnEntry is a clobber, this must be a phi.
855 auto *DefChainPhi = cast<MemoryPhi>(DefChainEnd);
856
857 PriorPathsSize = Paths.size();
858 PausedSearches.clear();
859 for (ListIndex I : NewPaused)
860 addSearches(DefChainPhi, PausedSearches, I);
861 NewPaused.clear();
862
863 Current = DefChainPhi;
864 }
865 }
866
867 void verifyOptResult(const OptznResult &R) const {
868 assert(all_of(R.OtherClobbers, [&](const TerminatedPath &P) {((all_of(R.OtherClobbers, [&](const TerminatedPath &P
) { return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber
); })) ? static_cast<void> (0) : __assert_fail ("all_of(R.OtherClobbers, [&](const TerminatedPath &P) { return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber); })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 870, __PRETTY_FUNCTION__))
869 return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber);((all_of(R.OtherClobbers, [&](const TerminatedPath &P
) { return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber
); })) ? static_cast<void> (0) : __assert_fail ("all_of(R.OtherClobbers, [&](const TerminatedPath &P) { return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber); })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 870, __PRETTY_FUNCTION__))
870 }))((all_of(R.OtherClobbers, [&](const TerminatedPath &P
) { return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber
); })) ? static_cast<void> (0) : __assert_fail ("all_of(R.OtherClobbers, [&](const TerminatedPath &P) { return MSSA.dominates(P.Clobber, R.PrimaryClobber.Clobber); })"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 870, __PRETTY_FUNCTION__))
;
871 }
872
873 void resetPhiOptznState() {
874 Paths.clear();
875 VisitedPhis.clear();
876 }
877
878public:
879 ClobberWalker(const MemorySSA &MSSA, AliasAnalysis &AA, DominatorTree &DT)
880 : MSSA(MSSA), AA(AA), DT(DT) {}
881
882 /// Finds the nearest clobber for the given query, optimizing phis if
883 /// possible.
884 MemoryAccess *findClobber(MemoryAccess *Start, UpwardsMemoryQuery &Q) {
885 Query = &Q;
886
887 MemoryAccess *Current = Start;
888 // This walker pretends uses don't exist. If we're handed one, silently grab
889 // its def. (This has the nice side-effect of ensuring we never cache uses)
890 if (auto *MU = dyn_cast<MemoryUse>(Start))
891 Current = MU->getDefiningAccess();
892
893 DefPath FirstDesc(Q.StartingLoc, Current, Current, None);
894 // Fast path for the overly-common case (no crazy phi optimization
895 // necessary)
896 UpwardsWalkResult WalkResult = walkToPhiOrClobber(FirstDesc);
897 MemoryAccess *Result;
898 if (WalkResult.IsKnownClobber) {
899 Result = WalkResult.Result;
900 Q.AR = WalkResult.AR;
901 } else {
902 OptznResult OptRes = tryOptimizePhi(cast<MemoryPhi>(FirstDesc.Last),
903 Current, Q.StartingLoc);
904 verifyOptResult(OptRes);
905 resetPhiOptznState();
906 Result = OptRes.PrimaryClobber.Clobber;
907 }
908
909#ifdef EXPENSIVE_CHECKS
910 checkClobberSanity(Current, Result, Q.StartingLoc, MSSA, Q, AA);
911#endif
912 return Result;
913 }
914
915 void verify(const MemorySSA *MSSA) { assert(MSSA == &this->MSSA)((MSSA == &this->MSSA) ? static_cast<void> (0) :
__assert_fail ("MSSA == &this->MSSA", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 915, __PRETTY_FUNCTION__))
; }
916};
917
918struct RenamePassData {
919 DomTreeNode *DTN;
920 DomTreeNode::const_iterator ChildIt;
921 MemoryAccess *IncomingVal;
922
923 RenamePassData(DomTreeNode *D, DomTreeNode::const_iterator It,
924 MemoryAccess *M)
925 : DTN(D), ChildIt(It), IncomingVal(M) {}
926
927 void swap(RenamePassData &RHS) {
928 std::swap(DTN, RHS.DTN);
929 std::swap(ChildIt, RHS.ChildIt);
930 std::swap(IncomingVal, RHS.IncomingVal);
931 }
932};
933
934} // end anonymous namespace
935
936namespace llvm {
937
938/// A MemorySSAWalker that does AA walks to disambiguate accesses. It no
939/// longer does caching on its own, but the name has been retained for the
940/// moment.
941class MemorySSA::CachingWalker final : public MemorySSAWalker {
942 ClobberWalker Walker;
943
944 MemoryAccess *getClobberingMemoryAccess(MemoryAccess *, UpwardsMemoryQuery &);
945
946public:
947 CachingWalker(MemorySSA *, AliasAnalysis *, DominatorTree *);
948 ~CachingWalker() override = default;
949
950 using MemorySSAWalker::getClobberingMemoryAccess;
951
952 MemoryAccess *getClobberingMemoryAccess(MemoryAccess *) override;
953 MemoryAccess *getClobberingMemoryAccess(MemoryAccess *,
954 const MemoryLocation &) override;
955 void invalidateInfo(MemoryAccess *) override;
956
957 void verify(const MemorySSA *MSSA) override {
958 MemorySSAWalker::verify(MSSA);
959 Walker.verify(MSSA);
960 }
961};
962
963} // end namespace llvm
964
965void MemorySSA::renameSuccessorPhis(BasicBlock *BB, MemoryAccess *IncomingVal,
966 bool RenameAllUses) {
967 // Pass through values to our successors
968 for (const BasicBlock *S : successors(BB)) {
969 auto It = PerBlockAccesses.find(S);
970 // Rename the phi nodes in our successor block
971 if (It == PerBlockAccesses.end() || !isa<MemoryPhi>(It->second->front()))
972 continue;
973 AccessList *Accesses = It->second.get();
974 auto *Phi = cast<MemoryPhi>(&Accesses->front());
975 if (RenameAllUses) {
976 int PhiIndex = Phi->getBasicBlockIndex(BB);
977 assert(PhiIndex != -1 && "Incomplete phi during partial rename")((PhiIndex != -1 && "Incomplete phi during partial rename"
) ? static_cast<void> (0) : __assert_fail ("PhiIndex != -1 && \"Incomplete phi during partial rename\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 977, __PRETTY_FUNCTION__))
;
978 Phi->setIncomingValue(PhiIndex, IncomingVal);
979 } else
980 Phi->addIncoming(IncomingVal, BB);
981 }
982}
983
984/// Rename a single basic block into MemorySSA form.
985/// Uses the standard SSA renaming algorithm.
986/// \returns The new incoming value.
987MemoryAccess *MemorySSA::renameBlock(BasicBlock *BB, MemoryAccess *IncomingVal,
988 bool RenameAllUses) {
989 auto It = PerBlockAccesses.find(BB);
990 // Skip most processing if the list is empty.
991 if (It != PerBlockAccesses.end()) {
992 AccessList *Accesses = It->second.get();
993 for (MemoryAccess &L : *Accesses) {
994 if (MemoryUseOrDef *MUD = dyn_cast<MemoryUseOrDef>(&L)) {
995 if (MUD->getDefiningAccess() == nullptr || RenameAllUses)
996 MUD->setDefiningAccess(IncomingVal);
997 if (isa<MemoryDef>(&L))
998 IncomingVal = &L;
999 } else {
1000 IncomingVal = &L;
1001 }
1002 }
1003 }
1004 return IncomingVal;
1005}
1006
1007/// This is the standard SSA renaming algorithm.
1008///
1009/// We walk the dominator tree in preorder, renaming accesses, and then filling
1010/// in phi nodes in our successors.
1011void MemorySSA::renamePass(DomTreeNode *Root, MemoryAccess *IncomingVal,
1012 SmallPtrSetImpl<BasicBlock *> &Visited,
1013 bool SkipVisited, bool RenameAllUses) {
1014 SmallVector<RenamePassData, 32> WorkStack;
1015 // Skip everything if we already renamed this block and we are skipping.
1016 // Note: You can't sink this into the if, because we need it to occur
1017 // regardless of whether we skip blocks or not.
1018 bool AlreadyVisited = !Visited.insert(Root->getBlock()).second;
1019 if (SkipVisited && AlreadyVisited)
1020 return;
1021
1022 IncomingVal = renameBlock(Root->getBlock(), IncomingVal, RenameAllUses);
1023 renameSuccessorPhis(Root->getBlock(), IncomingVal, RenameAllUses);
1024 WorkStack.push_back({Root, Root->begin(), IncomingVal});
1025
1026 while (!WorkStack.empty()) {
1027 DomTreeNode *Node = WorkStack.back().DTN;
1028 DomTreeNode::const_iterator ChildIt = WorkStack.back().ChildIt;
1029 IncomingVal = WorkStack.back().IncomingVal;
1030
1031 if (ChildIt == Node->end()) {
1032 WorkStack.pop_back();
1033 } else {
1034 DomTreeNode *Child = *ChildIt;
1035 ++WorkStack.back().ChildIt;
1036 BasicBlock *BB = Child->getBlock();
1037 // Note: You can't sink this into the if, because we need it to occur
1038 // regardless of whether we skip blocks or not.
1039 AlreadyVisited = !Visited.insert(BB).second;
1040 if (SkipVisited && AlreadyVisited) {
1041 // We already visited this during our renaming, which can happen when
1042 // being asked to rename multiple blocks. Figure out the incoming val,
1043 // which is the last def.
1044 // Incoming value can only change if there is a block def, and in that
1045 // case, it's the last block def in the list.
1046 if (auto *BlockDefs = getWritableBlockDefs(BB))
1047 IncomingVal = &*BlockDefs->rbegin();
1048 } else
1049 IncomingVal = renameBlock(BB, IncomingVal, RenameAllUses);
1050 renameSuccessorPhis(BB, IncomingVal, RenameAllUses);
1051 WorkStack.push_back({Child, Child->begin(), IncomingVal});
1052 }
1053 }
1054}
1055
1056/// This handles unreachable block accesses by deleting phi nodes in
1057/// unreachable blocks, and marking all other unreachable MemoryAccess's as
1058/// being uses of the live on entry definition.
1059void MemorySSA::markUnreachableAsLiveOnEntry(BasicBlock *BB) {
1060 assert(!DT->isReachableFromEntry(BB) &&((!DT->isReachableFromEntry(BB) && "Reachable block found while handling unreachable blocks"
) ? static_cast<void> (0) : __assert_fail ("!DT->isReachableFromEntry(BB) && \"Reachable block found while handling unreachable blocks\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1061, __PRETTY_FUNCTION__))
1061 "Reachable block found while handling unreachable blocks")((!DT->isReachableFromEntry(BB) && "Reachable block found while handling unreachable blocks"
) ? static_cast<void> (0) : __assert_fail ("!DT->isReachableFromEntry(BB) && \"Reachable block found while handling unreachable blocks\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1061, __PRETTY_FUNCTION__))
;
1062
1063 // Make sure phi nodes in our reachable successors end up with a
1064 // LiveOnEntryDef for our incoming edge, even though our block is forward
1065 // unreachable. We could just disconnect these blocks from the CFG fully,
1066 // but we do not right now.
1067 for (const BasicBlock *S : successors(BB)) {
1068 if (!DT->isReachableFromEntry(S))
1069 continue;
1070 auto It = PerBlockAccesses.find(S);
1071 // Rename the phi nodes in our successor block
1072 if (It == PerBlockAccesses.end() || !isa<MemoryPhi>(It->second->front()))
1073 continue;
1074 AccessList *Accesses = It->second.get();
1075 auto *Phi = cast<MemoryPhi>(&Accesses->front());
1076 Phi->addIncoming(LiveOnEntryDef.get(), BB);
1077 }
1078
1079 auto It = PerBlockAccesses.find(BB);
1080 if (It == PerBlockAccesses.end())
1081 return;
1082
1083 auto &Accesses = It->second;
1084 for (auto AI = Accesses->begin(), AE = Accesses->end(); AI != AE;) {
1085 auto Next = std::next(AI);
1086 // If we have a phi, just remove it. We are going to replace all
1087 // users with live on entry.
1088 if (auto *UseOrDef = dyn_cast<MemoryUseOrDef>(AI))
1089 UseOrDef->setDefiningAccess(LiveOnEntryDef.get());
1090 else
1091 Accesses->erase(AI);
1092 AI = Next;
1093 }
1094}
1095
1096MemorySSA::MemorySSA(Function &Func, AliasAnalysis *AA, DominatorTree *DT)
1097 : AA(AA), DT(DT), F(Func), LiveOnEntryDef(nullptr), Walker(nullptr),
1098 NextID(0) {
1099 buildMemorySSA();
1100}
1101
1102MemorySSA::~MemorySSA() {
1103 // Drop all our references
1104 for (const auto &Pair : PerBlockAccesses)
1105 for (MemoryAccess &MA : *Pair.second)
1106 MA.dropAllReferences();
1107}
1108
1109MemorySSA::AccessList *MemorySSA::getOrCreateAccessList(const BasicBlock *BB) {
1110 auto Res = PerBlockAccesses.insert(std::make_pair(BB, nullptr));
1111
1112 if (Res.second)
1113 Res.first->second = llvm::make_unique<AccessList>();
1114 return Res.first->second.get();
1115}
1116
1117MemorySSA::DefsList *MemorySSA::getOrCreateDefsList(const BasicBlock *BB) {
1118 auto Res = PerBlockDefs.insert(std::make_pair(BB, nullptr));
1119
1120 if (Res.second)
1121 Res.first->second = llvm::make_unique<DefsList>();
1122 return Res.first->second.get();
1123}
1124
1125namespace llvm {
1126
1127/// This class is a batch walker of all MemoryUse's in the program, and points
1128/// their defining access at the thing that actually clobbers them. Because it
1129/// is a batch walker that touches everything, it does not operate like the
1130/// other walkers. This walker is basically performing a top-down SSA renaming
1131/// pass, where the version stack is used as the cache. This enables it to be
1132/// significantly more time and memory efficient than using the regular walker,
1133/// which is walking bottom-up.
1134class MemorySSA::OptimizeUses {
1135public:
1136 OptimizeUses(MemorySSA *MSSA, MemorySSAWalker *Walker, AliasAnalysis *AA,
1137 DominatorTree *DT)
1138 : MSSA(MSSA), Walker(Walker), AA(AA), DT(DT) {
1139 Walker = MSSA->getWalker();
1140 }
1141
1142 void optimizeUses();
1143
1144private:
1145 /// This represents where a given memorylocation is in the stack.
1146 struct MemlocStackInfo {
1147 // This essentially is keeping track of versions of the stack. Whenever
1148 // the stack changes due to pushes or pops, these versions increase.
1149 unsigned long StackEpoch;
1150 unsigned long PopEpoch;
1151 // This is the lower bound of places on the stack to check. It is equal to
1152 // the place the last stack walk ended.
1153 // Note: Correctness depends on this being initialized to 0, which densemap
1154 // does
1155 unsigned long LowerBound;
1156 const BasicBlock *LowerBoundBlock;
1157 // This is where the last walk for this memory location ended.
1158 unsigned long LastKill;
1159 bool LastKillValid;
1160 Optional<AliasResult> AR;
1161 };
1162
1163 void optimizeUsesInBlock(const BasicBlock *, unsigned long &, unsigned long &,
1164 SmallVectorImpl<MemoryAccess *> &,
1165 DenseMap<MemoryLocOrCall, MemlocStackInfo> &);
1166
1167 MemorySSA *MSSA;
1168 MemorySSAWalker *Walker;
1169 AliasAnalysis *AA;
1170 DominatorTree *DT;
1171};
1172
1173} // end namespace llvm
1174
1175/// Optimize the uses in a given block This is basically the SSA renaming
1176/// algorithm, with one caveat: We are able to use a single stack for all
1177/// MemoryUses. This is because the set of *possible* reaching MemoryDefs is
1178/// the same for every MemoryUse. The *actual* clobbering MemoryDef is just
1179/// going to be some position in that stack of possible ones.
1180///
1181/// We track the stack positions that each MemoryLocation needs
1182/// to check, and last ended at. This is because we only want to check the
1183/// things that changed since last time. The same MemoryLocation should
1184/// get clobbered by the same store (getModRefInfo does not use invariantness or
1185/// things like this, and if they start, we can modify MemoryLocOrCall to
1186/// include relevant data)
1187void MemorySSA::OptimizeUses::optimizeUsesInBlock(
1188 const BasicBlock *BB, unsigned long &StackEpoch, unsigned long &PopEpoch,
1189 SmallVectorImpl<MemoryAccess *> &VersionStack,
1190 DenseMap<MemoryLocOrCall, MemlocStackInfo> &LocStackInfo) {
1191
1192 /// If no accesses, nothing to do.
1193 MemorySSA::AccessList *Accesses = MSSA->getWritableBlockAccesses(BB);
1194 if (Accesses == nullptr)
1195 return;
1196
1197 // Pop everything that doesn't dominate the current block off the stack,
1198 // increment the PopEpoch to account for this.
1199 while (true) {
1200 assert(((!VersionStack.empty() && "Version stack should have liveOnEntry sentinel dominating everything"
) ? static_cast<void> (0) : __assert_fail ("!VersionStack.empty() && \"Version stack should have liveOnEntry sentinel dominating everything\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1202, __PRETTY_FUNCTION__))
1201 !VersionStack.empty() &&((!VersionStack.empty() && "Version stack should have liveOnEntry sentinel dominating everything"
) ? static_cast<void> (0) : __assert_fail ("!VersionStack.empty() && \"Version stack should have liveOnEntry sentinel dominating everything\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1202, __PRETTY_FUNCTION__))
1202 "Version stack should have liveOnEntry sentinel dominating everything")((!VersionStack.empty() && "Version stack should have liveOnEntry sentinel dominating everything"
) ? static_cast<void> (0) : __assert_fail ("!VersionStack.empty() && \"Version stack should have liveOnEntry sentinel dominating everything\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1202, __PRETTY_FUNCTION__))
;
1203 BasicBlock *BackBlock = VersionStack.back()->getBlock();
1204 if (DT->dominates(BackBlock, BB))
1205 break;
1206 while (VersionStack.back()->getBlock() == BackBlock)
1207 VersionStack.pop_back();
1208 ++PopEpoch;
1209 }
1210
1211 for (MemoryAccess &MA : *Accesses) {
1212 auto *MU = dyn_cast<MemoryUse>(&MA);
1213 if (!MU) {
1214 VersionStack.push_back(&MA);
1215 ++StackEpoch;
1216 continue;
1217 }
1218
1219 if (isUseTriviallyOptimizableToLiveOnEntry(*AA, MU->getMemoryInst())) {
1220 MU->setDefiningAccess(MSSA->getLiveOnEntryDef(), true, None);
1221 continue;
1222 }
1223
1224 MemoryLocOrCall UseMLOC(MU);
1225 auto &LocInfo = LocStackInfo[UseMLOC];
1226 // If the pop epoch changed, it means we've removed stuff from top of
1227 // stack due to changing blocks. We may have to reset the lower bound or
1228 // last kill info.
1229 if (LocInfo.PopEpoch != PopEpoch) {
1230 LocInfo.PopEpoch = PopEpoch;
1231 LocInfo.StackEpoch = StackEpoch;
1232 // If the lower bound was in something that no longer dominates us, we
1233 // have to reset it.
1234 // We can't simply track stack size, because the stack may have had
1235 // pushes/pops in the meantime.
1236 // XXX: This is non-optimal, but only is slower cases with heavily
1237 // branching dominator trees. To get the optimal number of queries would
1238 // be to make lowerbound and lastkill a per-loc stack, and pop it until
1239 // the top of that stack dominates us. This does not seem worth it ATM.
1240 // A much cheaper optimization would be to always explore the deepest
1241 // branch of the dominator tree first. This will guarantee this resets on
1242 // the smallest set of blocks.
1243 if (LocInfo.LowerBoundBlock && LocInfo.LowerBoundBlock != BB &&
1244 !DT->dominates(LocInfo.LowerBoundBlock, BB)) {
1245 // Reset the lower bound of things to check.
1246 // TODO: Some day we should be able to reset to last kill, rather than
1247 // 0.
1248 LocInfo.LowerBound = 0;
1249 LocInfo.LowerBoundBlock = VersionStack[0]->getBlock();
1250 LocInfo.LastKillValid = false;
1251 }
1252 } else if (LocInfo.StackEpoch != StackEpoch) {
1253 // If all that has changed is the StackEpoch, we only have to check the
1254 // new things on the stack, because we've checked everything before. In
1255 // this case, the lower bound of things to check remains the same.
1256 LocInfo.PopEpoch = PopEpoch;
1257 LocInfo.StackEpoch = StackEpoch;
1258 }
1259 if (!LocInfo.LastKillValid) {
1260 LocInfo.LastKill = VersionStack.size() - 1;
1261 LocInfo.LastKillValid = true;
1262 LocInfo.AR = MayAlias;
1263 }
1264
1265 // At this point, we should have corrected last kill and LowerBound to be
1266 // in bounds.
1267 assert(LocInfo.LowerBound < VersionStack.size() &&((LocInfo.LowerBound < VersionStack.size() && "Lower bound out of range"
) ? static_cast<void> (0) : __assert_fail ("LocInfo.LowerBound < VersionStack.size() && \"Lower bound out of range\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1268, __PRETTY_FUNCTION__))
1268 "Lower bound out of range")((LocInfo.LowerBound < VersionStack.size() && "Lower bound out of range"
) ? static_cast<void> (0) : __assert_fail ("LocInfo.LowerBound < VersionStack.size() && \"Lower bound out of range\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1268, __PRETTY_FUNCTION__))
;
1269 assert(LocInfo.LastKill < VersionStack.size() &&((LocInfo.LastKill < VersionStack.size() && "Last kill info out of range"
) ? static_cast<void> (0) : __assert_fail ("LocInfo.LastKill < VersionStack.size() && \"Last kill info out of range\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1270, __PRETTY_FUNCTION__))
1270 "Last kill info out of range")((LocInfo.LastKill < VersionStack.size() && "Last kill info out of range"
) ? static_cast<void> (0) : __assert_fail ("LocInfo.LastKill < VersionStack.size() && \"Last kill info out of range\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1270, __PRETTY_FUNCTION__))
;
1271 // In any case, the new upper bound is the top of the stack.
1272 unsigned long UpperBound = VersionStack.size() - 1;
1273
1274 if (UpperBound - LocInfo.LowerBound > MaxCheckLimit) {
1275 LLVM_DEBUG(dbgs() << "MemorySSA skipping optimization of " << *MU << " ("do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "MemorySSA skipping optimization of "
<< *MU << " (" << *(MU->getMemoryInst()
) << ")" << " because there are " << UpperBound
- LocInfo.LowerBound << " stores to disambiguate\n"; }
} while (false)
1276 << *(MU->getMemoryInst()) << ")"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "MemorySSA skipping optimization of "
<< *MU << " (" << *(MU->getMemoryInst()
) << ")" << " because there are " << UpperBound
- LocInfo.LowerBound << " stores to disambiguate\n"; }
} while (false)
1277 << " because there are "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "MemorySSA skipping optimization of "
<< *MU << " (" << *(MU->getMemoryInst()
) << ")" << " because there are " << UpperBound
- LocInfo.LowerBound << " stores to disambiguate\n"; }
} while (false)
1278 << UpperBound - LocInfo.LowerBounddo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "MemorySSA skipping optimization of "
<< *MU << " (" << *(MU->getMemoryInst()
) << ")" << " because there are " << UpperBound
- LocInfo.LowerBound << " stores to disambiguate\n"; }
} while (false)
1279 << " stores to disambiguate\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "MemorySSA skipping optimization of "
<< *MU << " (" << *(MU->getMemoryInst()
) << ")" << " because there are " << UpperBound
- LocInfo.LowerBound << " stores to disambiguate\n"; }
} while (false)
;
1280 // Because we did not walk, LastKill is no longer valid, as this may
1281 // have been a kill.
1282 LocInfo.LastKillValid = false;
1283 continue;
1284 }
1285 bool FoundClobberResult = false;
1286 while (UpperBound > LocInfo.LowerBound) {
1287 if (isa<MemoryPhi>(VersionStack[UpperBound])) {
1288 // For phis, use the walker, see where we ended up, go there
1289 Instruction *UseInst = MU->getMemoryInst();
1290 MemoryAccess *Result = Walker->getClobberingMemoryAccess(UseInst);
1291 // We are guaranteed to find it or something is wrong
1292 while (VersionStack[UpperBound] != Result) {
1293 assert(UpperBound != 0)((UpperBound != 0) ? static_cast<void> (0) : __assert_fail
("UpperBound != 0", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1293, __PRETTY_FUNCTION__))
;
1294 --UpperBound;
1295 }
1296 FoundClobberResult = true;
1297 break;
1298 }
1299
1300 MemoryDef *MD = cast<MemoryDef>(VersionStack[UpperBound]);
1301 // If the lifetime of the pointer ends at this instruction, it's live on
1302 // entry.
1303 if (!UseMLOC.IsCall && lifetimeEndsAt(MD, UseMLOC.getLoc(), *AA)) {
1304 // Reset UpperBound to liveOnEntryDef's place in the stack
1305 UpperBound = 0;
1306 FoundClobberResult = true;
1307 LocInfo.AR = MustAlias;
1308 break;
1309 }
1310 ClobberAlias CA = instructionClobbersQuery(MD, MU, UseMLOC, *AA);
1311 if (CA.IsClobber) {
1312 FoundClobberResult = true;
1313 LocInfo.AR = CA.AR;
1314 break;
1315 }
1316 --UpperBound;
1317 }
1318
1319 // Note: Phis always have AliasResult AR set to MayAlias ATM.
1320
1321 // At the end of this loop, UpperBound is either a clobber, or lower bound
1322 // PHI walking may cause it to be < LowerBound, and in fact, < LastKill.
1323 if (FoundClobberResult || UpperBound < LocInfo.LastKill) {
1324 // We were last killed now by where we got to
1325 if (MSSA->isLiveOnEntryDef(VersionStack[UpperBound]))
1326 LocInfo.AR = None;
1327 MU->setDefiningAccess(VersionStack[UpperBound], true, LocInfo.AR);
1328 LocInfo.LastKill = UpperBound;
1329 } else {
1330 // Otherwise, we checked all the new ones, and now we know we can get to
1331 // LastKill.
1332 MU->setDefiningAccess(VersionStack[LocInfo.LastKill], true, LocInfo.AR);
1333 }
1334 LocInfo.LowerBound = VersionStack.size() - 1;
1335 LocInfo.LowerBoundBlock = BB;
1336 }
1337}
1338
1339/// Optimize uses to point to their actual clobbering definitions.
1340void MemorySSA::OptimizeUses::optimizeUses() {
1341 SmallVector<MemoryAccess *, 16> VersionStack;
1342 DenseMap<MemoryLocOrCall, MemlocStackInfo> LocStackInfo;
1343 VersionStack.push_back(MSSA->getLiveOnEntryDef());
1344
1345 unsigned long StackEpoch = 1;
1346 unsigned long PopEpoch = 1;
1347 // We perform a non-recursive top-down dominator tree walk.
1348 for (const auto *DomNode : depth_first(DT->getRootNode()))
1349 optimizeUsesInBlock(DomNode->getBlock(), StackEpoch, PopEpoch, VersionStack,
1350 LocStackInfo);
1351}
1352
1353void MemorySSA::placePHINodes(
1354 const SmallPtrSetImpl<BasicBlock *> &DefiningBlocks) {
1355 // Determine where our MemoryPhi's should go
1356 ForwardIDFCalculator IDFs(*DT);
1357 IDFs.setDefiningBlocks(DefiningBlocks);
1358 SmallVector<BasicBlock *, 32> IDFBlocks;
1359 IDFs.calculate(IDFBlocks);
1360
1361 // Now place MemoryPhi nodes.
1362 for (auto &BB : IDFBlocks)
1363 createMemoryPhi(BB);
1364}
1365
1366void MemorySSA::buildMemorySSA() {
1367 // We create an access to represent "live on entry", for things like
1368 // arguments or users of globals, where the memory they use is defined before
1369 // the beginning of the function. We do not actually insert it into the IR.
1370 // We do not define a live on exit for the immediate uses, and thus our
1371 // semantics do *not* imply that something with no immediate uses can simply
1372 // be removed.
1373 BasicBlock &StartingPoint = F.getEntryBlock();
1374 LiveOnEntryDef.reset(new MemoryDef(F.getContext(), nullptr, nullptr,
1375 &StartingPoint, NextID++));
1376
1377 // We maintain lists of memory accesses per-block, trading memory for time. We
1378 // could just look up the memory access for every possible instruction in the
1379 // stream.
1380 SmallPtrSet<BasicBlock *, 32> DefiningBlocks;
1381 // Go through each block, figure out where defs occur, and chain together all
1382 // the accesses.
1383 for (BasicBlock &B : F) {
1384 bool InsertIntoDef = false;
1385 AccessList *Accesses = nullptr;
1386 DefsList *Defs = nullptr;
1387 for (Instruction &I : B) {
1388 MemoryUseOrDef *MUD = createNewAccess(&I);
1389 if (!MUD)
1390 continue;
1391
1392 if (!Accesses)
1393 Accesses = getOrCreateAccessList(&B);
1394 Accesses->push_back(MUD);
1395 if (isa<MemoryDef>(MUD)) {
1396 InsertIntoDef = true;
1397 if (!Defs)
1398 Defs = getOrCreateDefsList(&B);
1399 Defs->push_back(*MUD);
1400 }
1401 }
1402 if (InsertIntoDef)
1403 DefiningBlocks.insert(&B);
1404 }
1405 placePHINodes(DefiningBlocks);
1406
1407 // Now do regular SSA renaming on the MemoryDef/MemoryUse. Visited will get
1408 // filled in with all blocks.
1409 SmallPtrSet<BasicBlock *, 16> Visited;
1410 renamePass(DT->getRootNode(), LiveOnEntryDef.get(), Visited);
1411
1412 CachingWalker *Walker = getWalkerImpl();
1413
1414 OptimizeUses(this, Walker, AA, DT).optimizeUses();
1415
1416 // Mark the uses in unreachable blocks as live on entry, so that they go
1417 // somewhere.
1418 for (auto &BB : F)
1419 if (!Visited.count(&BB))
1420 markUnreachableAsLiveOnEntry(&BB);
1421}
1422
1423MemorySSAWalker *MemorySSA::getWalker() { return getWalkerImpl(); }
1424
1425MemorySSA::CachingWalker *MemorySSA::getWalkerImpl() {
1426 if (Walker)
1427 return Walker.get();
1428
1429 Walker = llvm::make_unique<CachingWalker>(this, AA, DT);
1430 return Walker.get();
1431}
1432
1433// This is a helper function used by the creation routines. It places NewAccess
1434// into the access and defs lists for a given basic block, at the given
1435// insertion point.
1436void MemorySSA::insertIntoListsForBlock(MemoryAccess *NewAccess,
1437 const BasicBlock *BB,
1438 InsertionPlace Point) {
1439 auto *Accesses = getOrCreateAccessList(BB);
1440 if (Point == Beginning) {
1441 // If it's a phi node, it goes first, otherwise, it goes after any phi
1442 // nodes.
1443 if (isa<MemoryPhi>(NewAccess)) {
1444 Accesses->push_front(NewAccess);
1445 auto *Defs = getOrCreateDefsList(BB);
1446 Defs->push_front(*NewAccess);
1447 } else {
1448 auto AI = find_if_not(
1449 *Accesses, [](const MemoryAccess &MA) { return isa<MemoryPhi>(MA); });
1450 Accesses->insert(AI, NewAccess);
1451 if (!isa<MemoryUse>(NewAccess)) {
1452 auto *Defs = getOrCreateDefsList(BB);
1453 auto DI = find_if_not(
1454 *Defs, [](const MemoryAccess &MA) { return isa<MemoryPhi>(MA); });
1455 Defs->insert(DI, *NewAccess);
1456 }
1457 }
1458 } else {
1459 Accesses->push_back(NewAccess);
1460 if (!isa<MemoryUse>(NewAccess)) {
1461 auto *Defs = getOrCreateDefsList(BB);
1462 Defs->push_back(*NewAccess);
1463 }
1464 }
1465 BlockNumberingValid.erase(BB);
1466}
1467
1468void MemorySSA::insertIntoListsBefore(MemoryAccess *What, const BasicBlock *BB,
1469 AccessList::iterator InsertPt) {
1470 auto *Accesses = getWritableBlockAccesses(BB);
1471 bool WasEnd = InsertPt == Accesses->end();
1472 Accesses->insert(AccessList::iterator(InsertPt), What);
1473 if (!isa<MemoryUse>(What)) {
1474 auto *Defs = getOrCreateDefsList(BB);
1475 // If we got asked to insert at the end, we have an easy job, just shove it
1476 // at the end. If we got asked to insert before an existing def, we also get
1477 // an iterator. If we got asked to insert before a use, we have to hunt for
1478 // the next def.
1479 if (WasEnd) {
1480 Defs->push_back(*What);
1481 } else if (isa<MemoryDef>(InsertPt)) {
1482 Defs->insert(InsertPt->getDefsIterator(), *What);
1483 } else {
1484 while (InsertPt != Accesses->end() && !isa<MemoryDef>(InsertPt))
1485 ++InsertPt;
1486 // Either we found a def, or we are inserting at the end
1487 if (InsertPt == Accesses->end())
1488 Defs->push_back(*What);
1489 else
1490 Defs->insert(InsertPt->getDefsIterator(), *What);
1491 }
1492 }
1493 BlockNumberingValid.erase(BB);
1494}
1495
1496void MemorySSA::prepareForMoveTo(MemoryAccess *What, BasicBlock *BB) {
1497 // Keep it in the lookup tables, remove from the lists
1498 removeFromLists(What, false);
1499
1500 // Note that moving should implicitly invalidate the optimized state of a
1501 // MemoryUse (and Phis can't be optimized). However, it doesn't do so for a
1502 // MemoryDef.
1503 if (auto *MD = dyn_cast<MemoryDef>(What))
1504 MD->resetOptimized();
1505 What->setBlock(BB);
1506}
1507
1508// Move What before Where in the IR. The end result is that What will belong to
1509// the right lists and have the right Block set, but will not otherwise be
1510// correct. It will not have the right defining access, and if it is a def,
1511// things below it will not properly be updated.
1512void MemorySSA::moveTo(MemoryUseOrDef *What, BasicBlock *BB,
1513 AccessList::iterator Where) {
1514 prepareForMoveTo(What, BB);
1515 insertIntoListsBefore(What, BB, Where);
1516}
1517
1518void MemorySSA::moveTo(MemoryAccess *What, BasicBlock *BB,
1519 InsertionPlace Point) {
1520 if (isa<MemoryPhi>(What)) {
1521 assert(Point == Beginning &&((Point == Beginning && "Can only move a Phi at the beginning of the block"
) ? static_cast<void> (0) : __assert_fail ("Point == Beginning && \"Can only move a Phi at the beginning of the block\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1522, __PRETTY_FUNCTION__))
1522 "Can only move a Phi at the beginning of the block")((Point == Beginning && "Can only move a Phi at the beginning of the block"
) ? static_cast<void> (0) : __assert_fail ("Point == Beginning && \"Can only move a Phi at the beginning of the block\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1522, __PRETTY_FUNCTION__))
;
1523 // Update lookup table entry
1524 ValueToMemoryAccess.erase(What->getBlock());
1525 bool Inserted = ValueToMemoryAccess.insert({BB, What}).second;
1526 (void)Inserted;
1527 assert(Inserted && "Cannot move a Phi to a block that already has one")((Inserted && "Cannot move a Phi to a block that already has one"
) ? static_cast<void> (0) : __assert_fail ("Inserted && \"Cannot move a Phi to a block that already has one\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1527, __PRETTY_FUNCTION__))
;
1528 }
1529
1530 prepareForMoveTo(What, BB);
1531 insertIntoListsForBlock(What, BB, Point);
1532}
1533
1534MemoryPhi *MemorySSA::createMemoryPhi(BasicBlock *BB) {
1535 assert(!getMemoryAccess(BB) && "MemoryPhi already exists for this BB")((!getMemoryAccess(BB) && "MemoryPhi already exists for this BB"
) ? static_cast<void> (0) : __assert_fail ("!getMemoryAccess(BB) && \"MemoryPhi already exists for this BB\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1535, __PRETTY_FUNCTION__))
;
1536 MemoryPhi *Phi = new MemoryPhi(BB->getContext(), BB, NextID++);
1537 // Phi's always are placed at the front of the block.
1538 insertIntoListsForBlock(Phi, BB, Beginning);
1539 ValueToMemoryAccess[BB] = Phi;
1540 return Phi;
1541}
1542
1543MemoryUseOrDef *MemorySSA::createDefinedAccess(Instruction *I,
1544 MemoryAccess *Definition,
1545 const MemoryUseOrDef *Template) {
1546 assert(!isa<PHINode>(I) && "Cannot create a defined access for a PHI")((!isa<PHINode>(I) && "Cannot create a defined access for a PHI"
) ? static_cast<void> (0) : __assert_fail ("!isa<PHINode>(I) && \"Cannot create a defined access for a PHI\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1546, __PRETTY_FUNCTION__))
;
1547 MemoryUseOrDef *NewAccess = createNewAccess(I, Template);
1548 assert(((NewAccess != nullptr && "Tried to create a memory access for a non-memory touching instruction"
) ? static_cast<void> (0) : __assert_fail ("NewAccess != nullptr && \"Tried to create a memory access for a non-memory touching instruction\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1550, __PRETTY_FUNCTION__))
1549 NewAccess != nullptr &&((NewAccess != nullptr && "Tried to create a memory access for a non-memory touching instruction"
) ? static_cast<void> (0) : __assert_fail ("NewAccess != nullptr && \"Tried to create a memory access for a non-memory touching instruction\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1550, __PRETTY_FUNCTION__))
1550 "Tried to create a memory access for a non-memory touching instruction")((NewAccess != nullptr && "Tried to create a memory access for a non-memory touching instruction"
) ? static_cast<void> (0) : __assert_fail ("NewAccess != nullptr && \"Tried to create a memory access for a non-memory touching instruction\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1550, __PRETTY_FUNCTION__))
;
1551 NewAccess->setDefiningAccess(Definition);
1552 return NewAccess;
1553}
1554
1555// Return true if the instruction has ordering constraints.
1556// Note specifically that this only considers stores and loads
1557// because others are still considered ModRef by getModRefInfo.
1558static inline bool isOrdered(const Instruction *I) {
1559 if (auto *SI = dyn_cast<StoreInst>(I)) {
1560 if (!SI->isUnordered())
1561 return true;
1562 } else if (auto *LI = dyn_cast<LoadInst>(I)) {
1563 if (!LI->isUnordered())
1564 return true;
1565 }
1566 return false;
1567}
1568
1569/// Helper function to create new memory accesses
1570MemoryUseOrDef *MemorySSA::createNewAccess(Instruction *I,
1571 const MemoryUseOrDef *Template) {
1572 // The assume intrinsic has a control dependency which we model by claiming
1573 // that it writes arbitrarily. Ignore that fake memory dependency here.
1574 // FIXME: Replace this special casing with a more accurate modelling of
1575 // assume's control dependency.
1576 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
1577 if (II->getIntrinsicID() == Intrinsic::assume)
1578 return nullptr;
1579
1580 bool Def, Use;
1581 if (Template) {
1582 Def = dyn_cast_or_null<MemoryDef>(Template) != nullptr;
1583 Use = dyn_cast_or_null<MemoryUse>(Template) != nullptr;
1584#if !defined(NDEBUG)
1585 ModRefInfo ModRef = AA->getModRefInfo(I, None);
1586 bool DefCheck, UseCheck;
1587 DefCheck = isModSet(ModRef) || isOrdered(I);
1588 UseCheck = isRefSet(ModRef);
1589 assert(Def == DefCheck && (Def || Use == UseCheck) && "Invalid template")((Def == DefCheck && (Def || Use == UseCheck) &&
"Invalid template") ? static_cast<void> (0) : __assert_fail
("Def == DefCheck && (Def || Use == UseCheck) && \"Invalid template\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1589, __PRETTY_FUNCTION__))
;
1590#endif
1591 } else {
1592 // Find out what affect this instruction has on memory.
1593 ModRefInfo ModRef = AA->getModRefInfo(I, None);
1594 // The isOrdered check is used to ensure that volatiles end up as defs
1595 // (atomics end up as ModRef right now anyway). Until we separate the
1596 // ordering chain from the memory chain, this enables people to see at least
1597 // some relative ordering to volatiles. Note that getClobberingMemoryAccess
1598 // will still give an answer that bypasses other volatile loads. TODO:
1599 // Separate memory aliasing and ordering into two different chains so that
1600 // we can precisely represent both "what memory will this read/write/is
1601 // clobbered by" and "what instructions can I move this past".
1602 Def = isModSet(ModRef) || isOrdered(I);
1603 Use = isRefSet(ModRef);
1604 }
1605
1606 // It's possible for an instruction to not modify memory at all. During
1607 // construction, we ignore them.
1608 if (!Def && !Use)
1609 return nullptr;
1610
1611 MemoryUseOrDef *MUD;
1612 if (Def)
1613 MUD = new MemoryDef(I->getContext(), nullptr, I, I->getParent(), NextID++);
1614 else
1615 MUD = new MemoryUse(I->getContext(), nullptr, I, I->getParent());
1616 ValueToMemoryAccess[I] = MUD;
1617 return MUD;
1618}
1619
1620/// Returns true if \p Replacer dominates \p Replacee .
1621bool MemorySSA::dominatesUse(const MemoryAccess *Replacer,
1622 const MemoryAccess *Replacee) const {
1623 if (isa<MemoryUseOrDef>(Replacee))
1624 return DT->dominates(Replacer->getBlock(), Replacee->getBlock());
1625 const auto *MP = cast<MemoryPhi>(Replacee);
1626 // For a phi node, the use occurs in the predecessor block of the phi node.
1627 // Since we may occur multiple times in the phi node, we have to check each
1628 // operand to ensure Replacer dominates each operand where Replacee occurs.
1629 for (const Use &Arg : MP->operands()) {
1630 if (Arg.get() != Replacee &&
1631 !DT->dominates(Replacer->getBlock(), MP->getIncomingBlock(Arg)))
1632 return false;
1633 }
1634 return true;
1635}
1636
1637/// Properly remove \p MA from all of MemorySSA's lookup tables.
1638void MemorySSA::removeFromLookups(MemoryAccess *MA) {
1639 assert(MA->use_empty() &&((MA->use_empty() && "Trying to remove memory access that still has uses"
) ? static_cast<void> (0) : __assert_fail ("MA->use_empty() && \"Trying to remove memory access that still has uses\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1640, __PRETTY_FUNCTION__))
1640 "Trying to remove memory access that still has uses")((MA->use_empty() && "Trying to remove memory access that still has uses"
) ? static_cast<void> (0) : __assert_fail ("MA->use_empty() && \"Trying to remove memory access that still has uses\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1640, __PRETTY_FUNCTION__))
;
1641 BlockNumbering.erase(MA);
1642 if (auto *MUD = dyn_cast<MemoryUseOrDef>(MA))
1643 MUD->setDefiningAccess(nullptr);
1644 // Invalidate our walker's cache if necessary
1645 if (!isa<MemoryUse>(MA))
1646 Walker->invalidateInfo(MA);
1647
1648 Value *MemoryInst;
1649 if (const auto *MUD = dyn_cast<MemoryUseOrDef>(MA))
1650 MemoryInst = MUD->getMemoryInst();
1651 else
1652 MemoryInst = MA->getBlock();
1653
1654 auto VMA = ValueToMemoryAccess.find(MemoryInst);
1655 if (VMA->second == MA)
1656 ValueToMemoryAccess.erase(VMA);
1657}
1658
1659/// Properly remove \p MA from all of MemorySSA's lists.
1660///
1661/// Because of the way the intrusive list and use lists work, it is important to
1662/// do removal in the right order.
1663/// ShouldDelete defaults to true, and will cause the memory access to also be
1664/// deleted, not just removed.
1665void MemorySSA::removeFromLists(MemoryAccess *MA, bool ShouldDelete) {
1666 BasicBlock *BB = MA->getBlock();
1667 // The access list owns the reference, so we erase it from the non-owning list
1668 // first.
1669 if (!isa<MemoryUse>(MA)) {
1670 auto DefsIt = PerBlockDefs.find(BB);
1671 std::unique_ptr<DefsList> &Defs = DefsIt->second;
1672 Defs->remove(*MA);
1673 if (Defs->empty())
1674 PerBlockDefs.erase(DefsIt);
1675 }
1676
1677 // The erase call here will delete it. If we don't want it deleted, we call
1678 // remove instead.
1679 auto AccessIt = PerBlockAccesses.find(BB);
1680 std::unique_ptr<AccessList> &Accesses = AccessIt->second;
1681 if (ShouldDelete)
1682 Accesses->erase(MA);
1683 else
1684 Accesses->remove(MA);
1685
1686 if (Accesses->empty()) {
1687 PerBlockAccesses.erase(AccessIt);
1688 BlockNumberingValid.erase(BB);
1689 }
1690}
1691
1692void MemorySSA::print(raw_ostream &OS) const {
1693 MemorySSAAnnotatedWriter Writer(this);
1694 F.print(OS, &Writer);
1695}
1696
1697#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
1698LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void MemorySSA::dump() const { print(dbgs()); }
1699#endif
1700
1701void MemorySSA::verifyMemorySSA() const {
1702 verifyDefUses(F);
1703 verifyDomination(F);
1704 verifyOrdering(F);
2
Calling 'MemorySSA::verifyOrdering'
1705 verifyDominationNumbers(F);
1706 Walker->verify(this);
1707 verifyClobberSanity(F);
1708}
1709
1710/// Check sanity of the clobbering instruction for access MA.
1711void MemorySSA::checkClobberSanityAccess(const MemoryAccess *MA) const {
1712 if (const auto *MUD = dyn_cast<MemoryUseOrDef>(MA)) {
1713 if (!MUD->isOptimized())
1714 return;
1715 auto *I = MUD->getMemoryInst();
1716 auto Loc = MemoryLocation::getOrNone(I);
1717 if (Loc == None)
1718 return;
1719 auto *Clobber = MUD->getOptimized();
1720 UpwardsMemoryQuery Q(I, MUD);
1721 checkClobberSanity(MUD, Clobber, *Loc, *this, Q, *AA, true);
1722 }
1723}
1724
1725void MemorySSA::verifyClobberSanity(const Function &F) const {
1726#if !defined(NDEBUG) && defined(EXPENSIVE_CHECKS)
1727 for (const BasicBlock &BB : F) {
1728 const AccessList *Accesses = getBlockAccesses(&BB);
1729 if (!Accesses)
1730 continue;
1731 for (const MemoryAccess &MA : *Accesses)
1732 checkClobberSanityAccess(&MA);
1733 }
1734#endif
1735}
1736
1737/// Verify that all of the blocks we believe to have valid domination numbers
1738/// actually have valid domination numbers.
1739void MemorySSA::verifyDominationNumbers(const Function &F) const {
1740#ifndef NDEBUG
1741 if (BlockNumberingValid.empty())
1742 return;
1743
1744 SmallPtrSet<const BasicBlock *, 16> ValidBlocks = BlockNumberingValid;
1745 for (const BasicBlock &BB : F) {
1746 if (!ValidBlocks.count(&BB))
1747 continue;
1748
1749 ValidBlocks.erase(&BB);
1750
1751 const AccessList *Accesses = getBlockAccesses(&BB);
1752 // It's correct to say an empty block has valid numbering.
1753 if (!Accesses)
1754 continue;
1755
1756 // Block numbering starts at 1.
1757 unsigned long LastNumber = 0;
1758 for (const MemoryAccess &MA : *Accesses) {
1759 auto ThisNumberIter = BlockNumbering.find(&MA);
1760 assert(ThisNumberIter != BlockNumbering.end() &&((ThisNumberIter != BlockNumbering.end() && "MemoryAccess has no domination number in a valid block!"
) ? static_cast<void> (0) : __assert_fail ("ThisNumberIter != BlockNumbering.end() && \"MemoryAccess has no domination number in a valid block!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1761, __PRETTY_FUNCTION__))
1761 "MemoryAccess has no domination number in a valid block!")((ThisNumberIter != BlockNumbering.end() && "MemoryAccess has no domination number in a valid block!"
) ? static_cast<void> (0) : __assert_fail ("ThisNumberIter != BlockNumbering.end() && \"MemoryAccess has no domination number in a valid block!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1761, __PRETTY_FUNCTION__))
;
1762
1763 unsigned long ThisNumber = ThisNumberIter->second;
1764 assert(ThisNumber > LastNumber &&((ThisNumber > LastNumber && "Domination numbers should be strictly increasing!"
) ? static_cast<void> (0) : __assert_fail ("ThisNumber > LastNumber && \"Domination numbers should be strictly increasing!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1765, __PRETTY_FUNCTION__))
1765 "Domination numbers should be strictly increasing!")((ThisNumber > LastNumber && "Domination numbers should be strictly increasing!"
) ? static_cast<void> (0) : __assert_fail ("ThisNumber > LastNumber && \"Domination numbers should be strictly increasing!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1765, __PRETTY_FUNCTION__))
;
1766 LastNumber = ThisNumber;
1767 }
1768 }
1769
1770 assert(ValidBlocks.empty() &&((ValidBlocks.empty() && "All valid BasicBlocks should exist in F -- dangling pointers?"
) ? static_cast<void> (0) : __assert_fail ("ValidBlocks.empty() && \"All valid BasicBlocks should exist in F -- dangling pointers?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1771, __PRETTY_FUNCTION__))
1771 "All valid BasicBlocks should exist in F -- dangling pointers?")((ValidBlocks.empty() && "All valid BasicBlocks should exist in F -- dangling pointers?"
) ? static_cast<void> (0) : __assert_fail ("ValidBlocks.empty() && \"All valid BasicBlocks should exist in F -- dangling pointers?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1771, __PRETTY_FUNCTION__))
;
1772#endif
1773}
1774
1775/// Verify that the order and existence of MemoryAccesses matches the
1776/// order and existence of memory affecting instructions.
1777void MemorySSA::verifyOrdering(Function &F) const {
1778#ifndef NDEBUG
1779 // Walk all the blocks, comparing what the lookups think and what the access
1780 // lists think, as well as the order in the blocks vs the order in the access
1781 // lists.
1782 SmallVector<MemoryAccess *, 32> ActualAccesses;
1783 SmallVector<MemoryAccess *, 32> ActualDefs;
1784 for (BasicBlock &B : F) {
1785 const AccessList *AL = getBlockAccesses(&B);
3
Calling 'MemorySSA::getBlockAccesses'
27
Returning from 'MemorySSA::getBlockAccesses'
28
'AL' initialized here
1786 const auto *DL = getBlockDefs(&B);
1787 MemoryAccess *Phi = getMemoryAccess(&B);
1788 if (Phi) {
29
Taking false branch
1789 ActualAccesses.push_back(Phi);
1790 ActualDefs.push_back(Phi);
1791 }
1792
1793 for (Instruction &I : B) {
1794 MemoryAccess *MA = getMemoryAccess(&I);
1795 assert((!MA || (AL && (isa<MemoryUse>(MA) || DL))) &&(((!MA || (AL && (isa<MemoryUse>(MA) || DL))) &&
"We have memory affecting instructions " "in this block but they are not in the "
"access list or defs list") ? static_cast<void> (0) : __assert_fail
("(!MA || (AL && (isa<MemoryUse>(MA) || DL))) && \"We have memory affecting instructions \" \"in this block but they are not in the \" \"access list or defs list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1798, __PRETTY_FUNCTION__))
1796 "We have memory affecting instructions "(((!MA || (AL && (isa<MemoryUse>(MA) || DL))) &&
"We have memory affecting instructions " "in this block but they are not in the "
"access list or defs list") ? static_cast<void> (0) : __assert_fail
("(!MA || (AL && (isa<MemoryUse>(MA) || DL))) && \"We have memory affecting instructions \" \"in this block but they are not in the \" \"access list or defs list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1798, __PRETTY_FUNCTION__))
1797 "in this block but they are not in the "(((!MA || (AL && (isa<MemoryUse>(MA) || DL))) &&
"We have memory affecting instructions " "in this block but they are not in the "
"access list or defs list") ? static_cast<void> (0) : __assert_fail
("(!MA || (AL && (isa<MemoryUse>(MA) || DL))) && \"We have memory affecting instructions \" \"in this block but they are not in the \" \"access list or defs list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1798, __PRETTY_FUNCTION__))
1798 "access list or defs list")(((!MA || (AL && (isa<MemoryUse>(MA) || DL))) &&
"We have memory affecting instructions " "in this block but they are not in the "
"access list or defs list") ? static_cast<void> (0) : __assert_fail
("(!MA || (AL && (isa<MemoryUse>(MA) || DL))) && \"We have memory affecting instructions \" \"in this block but they are not in the \" \"access list or defs list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1798, __PRETTY_FUNCTION__))
;
1799 if (MA) {
1800 ActualAccesses.push_back(MA);
1801 if (isa<MemoryDef>(MA))
1802 ActualDefs.push_back(MA);
1803 }
1804 }
1805 // Either we hit the assert, really have no accesses, or we have both
1806 // accesses and an access list.
1807 // Same with defs.
1808 if (!AL && !DL)
30
Assuming 'AL' is null
31
Assuming pointer value is null
32
Assuming 'DL' is non-null
33
Taking false branch
1809 continue;
1810 assert(AL->size() == ActualAccesses.size() &&((AL->size() == ActualAccesses.size() && "We don't have the same number of accesses in the block as on the "
"access list") ? static_cast<void> (0) : __assert_fail
("AL->size() == ActualAccesses.size() && \"We don't have the same number of accesses in the block as on the \" \"access list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1812, __PRETTY_FUNCTION__))
34
Within the expansion of the macro 'assert':
a
Called C++ object pointer is null
1811 "We don't have the same number of accesses in the block as on the "((AL->size() == ActualAccesses.size() && "We don't have the same number of accesses in the block as on the "
"access list") ? static_cast<void> (0) : __assert_fail
("AL->size() == ActualAccesses.size() && \"We don't have the same number of accesses in the block as on the \" \"access list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1812, __PRETTY_FUNCTION__))
1812 "access list")((AL->size() == ActualAccesses.size() && "We don't have the same number of accesses in the block as on the "
"access list") ? static_cast<void> (0) : __assert_fail
("AL->size() == ActualAccesses.size() && \"We don't have the same number of accesses in the block as on the \" \"access list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1812, __PRETTY_FUNCTION__))
;
1813 assert((DL || ActualDefs.size() == 0) &&(((DL || ActualDefs.size() == 0) && "Either we should have a defs list, or we should have no defs"
) ? static_cast<void> (0) : __assert_fail ("(DL || ActualDefs.size() == 0) && \"Either we should have a defs list, or we should have no defs\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1814, __PRETTY_FUNCTION__))
1814 "Either we should have a defs list, or we should have no defs")(((DL || ActualDefs.size() == 0) && "Either we should have a defs list, or we should have no defs"
) ? static_cast<void> (0) : __assert_fail ("(DL || ActualDefs.size() == 0) && \"Either we should have a defs list, or we should have no defs\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1814, __PRETTY_FUNCTION__))
;
1815 assert((!DL || DL->size() == ActualDefs.size()) &&(((!DL || DL->size() == ActualDefs.size()) && "We don't have the same number of defs in the block as on the "
"def list") ? static_cast<void> (0) : __assert_fail ("(!DL || DL->size() == ActualDefs.size()) && \"We don't have the same number of defs in the block as on the \" \"def list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1817, __PRETTY_FUNCTION__))
1816 "We don't have the same number of defs in the block as on the "(((!DL || DL->size() == ActualDefs.size()) && "We don't have the same number of defs in the block as on the "
"def list") ? static_cast<void> (0) : __assert_fail ("(!DL || DL->size() == ActualDefs.size()) && \"We don't have the same number of defs in the block as on the \" \"def list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1817, __PRETTY_FUNCTION__))
1817 "def list")(((!DL || DL->size() == ActualDefs.size()) && "We don't have the same number of defs in the block as on the "
"def list") ? static_cast<void> (0) : __assert_fail ("(!DL || DL->size() == ActualDefs.size()) && \"We don't have the same number of defs in the block as on the \" \"def list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1817, __PRETTY_FUNCTION__))
;
1818 auto ALI = AL->begin();
1819 auto AAI = ActualAccesses.begin();
1820 while (ALI != AL->end() && AAI != ActualAccesses.end()) {
1821 assert(&*ALI == *AAI && "Not the same accesses in the same order")((&*ALI == *AAI && "Not the same accesses in the same order"
) ? static_cast<void> (0) : __assert_fail ("&*ALI == *AAI && \"Not the same accesses in the same order\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1821, __PRETTY_FUNCTION__))
;
1822 ++ALI;
1823 ++AAI;
1824 }
1825 ActualAccesses.clear();
1826 if (DL) {
1827 auto DLI = DL->begin();
1828 auto ADI = ActualDefs.begin();
1829 while (DLI != DL->end() && ADI != ActualDefs.end()) {
1830 assert(&*DLI == *ADI && "Not the same defs in the same order")((&*DLI == *ADI && "Not the same defs in the same order"
) ? static_cast<void> (0) : __assert_fail ("&*DLI == *ADI && \"Not the same defs in the same order\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1830, __PRETTY_FUNCTION__))
;
1831 ++DLI;
1832 ++ADI;
1833 }
1834 }
1835 ActualDefs.clear();
1836 }
1837#endif
1838}
1839
1840/// Verify the domination properties of MemorySSA by checking that each
1841/// definition dominates all of its uses.
1842void MemorySSA::verifyDomination(Function &F) const {
1843#ifndef NDEBUG
1844 for (BasicBlock &B : F) {
1845 // Phi nodes are attached to basic blocks
1846 if (MemoryPhi *MP = getMemoryAccess(&B))
1847 for (const Use &U : MP->uses())
1848 assert(dominates(MP, U) && "Memory PHI does not dominate it's uses")((dominates(MP, U) && "Memory PHI does not dominate it's uses"
) ? static_cast<void> (0) : __assert_fail ("dominates(MP, U) && \"Memory PHI does not dominate it's uses\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1848, __PRETTY_FUNCTION__))
;
1849
1850 for (Instruction &I : B) {
1851 MemoryAccess *MD = dyn_cast_or_null<MemoryDef>(getMemoryAccess(&I));
1852 if (!MD)
1853 continue;
1854
1855 for (const Use &U : MD->uses())
1856 assert(dominates(MD, U) && "Memory Def does not dominate it's uses")((dominates(MD, U) && "Memory Def does not dominate it's uses"
) ? static_cast<void> (0) : __assert_fail ("dominates(MD, U) && \"Memory Def does not dominate it's uses\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1856, __PRETTY_FUNCTION__))
;
1857 }
1858 }
1859#endif
1860}
1861
1862/// Verify the def-use lists in MemorySSA, by verifying that \p Use
1863/// appears in the use list of \p Def.
1864void MemorySSA::verifyUseInDefs(MemoryAccess *Def, MemoryAccess *Use) const {
1865#ifndef NDEBUG
1866 // The live on entry use may cause us to get a NULL def here
1867 if (!Def)
1868 assert(isLiveOnEntryDef(Use) &&((isLiveOnEntryDef(Use) && "Null def but use not point to live on entry def"
) ? static_cast<void> (0) : __assert_fail ("isLiveOnEntryDef(Use) && \"Null def but use not point to live on entry def\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1869, __PRETTY_FUNCTION__))
1869 "Null def but use not point to live on entry def")((isLiveOnEntryDef(Use) && "Null def but use not point to live on entry def"
) ? static_cast<void> (0) : __assert_fail ("isLiveOnEntryDef(Use) && \"Null def but use not point to live on entry def\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1869, __PRETTY_FUNCTION__))
;
1870 else
1871 assert(is_contained(Def->users(), Use) &&((is_contained(Def->users(), Use) && "Did not find use in def's use list"
) ? static_cast<void> (0) : __assert_fail ("is_contained(Def->users(), Use) && \"Did not find use in def's use list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1872, __PRETTY_FUNCTION__))
1872 "Did not find use in def's use list")((is_contained(Def->users(), Use) && "Did not find use in def's use list"
) ? static_cast<void> (0) : __assert_fail ("is_contained(Def->users(), Use) && \"Did not find use in def's use list\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1872, __PRETTY_FUNCTION__))
;
1873#endif
1874}
1875
1876/// Verify the immediate use information, by walking all the memory
1877/// accesses and verifying that, for each use, it appears in the
1878/// appropriate def's use list
1879void MemorySSA::verifyDefUses(Function &F) const {
1880#ifndef NDEBUG
1881 for (BasicBlock &B : F) {
1882 // Phi nodes are attached to basic blocks
1883 if (MemoryPhi *Phi = getMemoryAccess(&B)) {
1884 assert(Phi->getNumOperands() == static_cast<unsigned>(std::distance(((Phi->getNumOperands() == static_cast<unsigned>(std
::distance( pred_begin(&B), pred_end(&B))) &&
"Incomplete MemoryPhi Node") ? static_cast<void> (0) :
__assert_fail ("Phi->getNumOperands() == static_cast<unsigned>(std::distance( pred_begin(&B), pred_end(&B))) && \"Incomplete MemoryPhi Node\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1886, __PRETTY_FUNCTION__))
1885 pred_begin(&B), pred_end(&B))) &&((Phi->getNumOperands() == static_cast<unsigned>(std
::distance( pred_begin(&B), pred_end(&B))) &&
"Incomplete MemoryPhi Node") ? static_cast<void> (0) :
__assert_fail ("Phi->getNumOperands() == static_cast<unsigned>(std::distance( pred_begin(&B), pred_end(&B))) && \"Incomplete MemoryPhi Node\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1886, __PRETTY_FUNCTION__))
1886 "Incomplete MemoryPhi Node")((Phi->getNumOperands() == static_cast<unsigned>(std
::distance( pred_begin(&B), pred_end(&B))) &&
"Incomplete MemoryPhi Node") ? static_cast<void> (0) :
__assert_fail ("Phi->getNumOperands() == static_cast<unsigned>(std::distance( pred_begin(&B), pred_end(&B))) && \"Incomplete MemoryPhi Node\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1886, __PRETTY_FUNCTION__))
;
1887 for (unsigned I = 0, E = Phi->getNumIncomingValues(); I != E; ++I) {
1888 verifyUseInDefs(Phi->getIncomingValue(I), Phi);
1889 assert(find(predecessors(&B), Phi->getIncomingBlock(I)) !=((find(predecessors(&B), Phi->getIncomingBlock(I)) != pred_end
(&B) && "Incoming phi block not a block predecessor"
) ? static_cast<void> (0) : __assert_fail ("find(predecessors(&B), Phi->getIncomingBlock(I)) != pred_end(&B) && \"Incoming phi block not a block predecessor\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1891, __PRETTY_FUNCTION__))
1890 pred_end(&B) &&((find(predecessors(&B), Phi->getIncomingBlock(I)) != pred_end
(&B) && "Incoming phi block not a block predecessor"
) ? static_cast<void> (0) : __assert_fail ("find(predecessors(&B), Phi->getIncomingBlock(I)) != pred_end(&B) && \"Incoming phi block not a block predecessor\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1891, __PRETTY_FUNCTION__))
1891 "Incoming phi block not a block predecessor")((find(predecessors(&B), Phi->getIncomingBlock(I)) != pred_end
(&B) && "Incoming phi block not a block predecessor"
) ? static_cast<void> (0) : __assert_fail ("find(predecessors(&B), Phi->getIncomingBlock(I)) != pred_end(&B) && \"Incoming phi block not a block predecessor\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1891, __PRETTY_FUNCTION__))
;
1892 }
1893 }
1894
1895 for (Instruction &I : B) {
1896 if (MemoryUseOrDef *MA = getMemoryAccess(&I)) {
1897 verifyUseInDefs(MA->getDefiningAccess(), MA);
1898 }
1899 }
1900 }
1901#endif
1902}
1903
1904/// Perform a local numbering on blocks so that instruction ordering can be
1905/// determined in constant time.
1906/// TODO: We currently just number in order. If we numbered by N, we could
1907/// allow at least N-1 sequences of insertBefore or insertAfter (and at least
1908/// log2(N) sequences of mixed before and after) without needing to invalidate
1909/// the numbering.
1910void MemorySSA::renumberBlock(const BasicBlock *B) const {
1911 // The pre-increment ensures the numbers really start at 1.
1912 unsigned long CurrentNumber = 0;
1913 const AccessList *AL = getBlockAccesses(B);
1914 assert(AL != nullptr && "Asking to renumber an empty block")((AL != nullptr && "Asking to renumber an empty block"
) ? static_cast<void> (0) : __assert_fail ("AL != nullptr && \"Asking to renumber an empty block\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1914, __PRETTY_FUNCTION__))
;
1915 for (const auto &I : *AL)
1916 BlockNumbering[&I] = ++CurrentNumber;
1917 BlockNumberingValid.insert(B);
1918}
1919
1920/// Determine, for two memory accesses in the same block,
1921/// whether \p Dominator dominates \p Dominatee.
1922/// \returns True if \p Dominator dominates \p Dominatee.
1923bool MemorySSA::locallyDominates(const MemoryAccess *Dominator,
1924 const MemoryAccess *Dominatee) const {
1925 const BasicBlock *DominatorBlock = Dominator->getBlock();
1926
1927 assert((DominatorBlock == Dominatee->getBlock()) &&(((DominatorBlock == Dominatee->getBlock()) && "Asking for local domination when accesses are in different blocks!"
) ? static_cast<void> (0) : __assert_fail ("(DominatorBlock == Dominatee->getBlock()) && \"Asking for local domination when accesses are in different blocks!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1928, __PRETTY_FUNCTION__))
1928 "Asking for local domination when accesses are in different blocks!")(((DominatorBlock == Dominatee->getBlock()) && "Asking for local domination when accesses are in different blocks!"
) ? static_cast<void> (0) : __assert_fail ("(DominatorBlock == Dominatee->getBlock()) && \"Asking for local domination when accesses are in different blocks!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1928, __PRETTY_FUNCTION__))
;
1929 // A node dominates itself.
1930 if (Dominatee == Dominator)
1931 return true;
1932
1933 // When Dominatee is defined on function entry, it is not dominated by another
1934 // memory access.
1935 if (isLiveOnEntryDef(Dominatee))
1936 return false;
1937
1938 // When Dominator is defined on function entry, it dominates the other memory
1939 // access.
1940 if (isLiveOnEntryDef(Dominator))
1941 return true;
1942
1943 if (!BlockNumberingValid.count(DominatorBlock))
1944 renumberBlock(DominatorBlock);
1945
1946 unsigned long DominatorNum = BlockNumbering.lookup(Dominator);
1947 // All numbers start with 1
1948 assert(DominatorNum != 0 && "Block was not numbered properly")((DominatorNum != 0 && "Block was not numbered properly"
) ? static_cast<void> (0) : __assert_fail ("DominatorNum != 0 && \"Block was not numbered properly\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1948, __PRETTY_FUNCTION__))
;
1949 unsigned long DominateeNum = BlockNumbering.lookup(Dominatee);
1950 assert(DominateeNum != 0 && "Block was not numbered properly")((DominateeNum != 0 && "Block was not numbered properly"
) ? static_cast<void> (0) : __assert_fail ("DominateeNum != 0 && \"Block was not numbered properly\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1950, __PRETTY_FUNCTION__))
;
1951 return DominatorNum < DominateeNum;
1952}
1953
1954bool MemorySSA::dominates(const MemoryAccess *Dominator,
1955 const MemoryAccess *Dominatee) const {
1956 if (Dominator == Dominatee)
1957 return true;
1958
1959 if (isLiveOnEntryDef(Dominatee))
1960 return false;
1961
1962 if (Dominator->getBlock() != Dominatee->getBlock())
1963 return DT->dominates(Dominator->getBlock(), Dominatee->getBlock());
1964 return locallyDominates(Dominator, Dominatee);
1965}
1966
1967bool MemorySSA::dominates(const MemoryAccess *Dominator,
1968 const Use &Dominatee) const {
1969 if (MemoryPhi *MP = dyn_cast<MemoryPhi>(Dominatee.getUser())) {
1970 BasicBlock *UseBB = MP->getIncomingBlock(Dominatee);
1971 // The def must dominate the incoming block of the phi.
1972 if (UseBB != Dominator->getBlock())
1973 return DT->dominates(Dominator->getBlock(), UseBB);
1974 // If the UseBB and the DefBB are the same, compare locally.
1975 return locallyDominates(Dominator, cast<MemoryAccess>(Dominatee));
1976 }
1977 // If it's not a PHI node use, the normal dominates can already handle it.
1978 return dominates(Dominator, cast<MemoryAccess>(Dominatee.getUser()));
1979}
1980
1981const static char LiveOnEntryStr[] = "liveOnEntry";
1982
1983void MemoryAccess::print(raw_ostream &OS) const {
1984 switch (getValueID()) {
1985 case MemoryPhiVal: return static_cast<const MemoryPhi *>(this)->print(OS);
1986 case MemoryDefVal: return static_cast<const MemoryDef *>(this)->print(OS);
1987 case MemoryUseVal: return static_cast<const MemoryUse *>(this)->print(OS);
1988 }
1989 llvm_unreachable("invalid value id")::llvm::llvm_unreachable_internal("invalid value id", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Analysis/MemorySSA.cpp"
, 1989)
;
1990}
1991
1992void MemoryDef::print(raw_ostream &OS) const {
1993 MemoryAccess *UO = getDefiningAccess();
1994
1995 auto printID = [&OS](MemoryAccess *A) {
1996 if (A && A->getID())
1997 OS << A->getID();
1998 else
1999 OS << LiveOnEntryStr;
2000 };
2001
2002 OS << getID() << " = MemoryDef(";
2003 printID(UO);
2004 OS << ")";
2005
2006 if (isOptimized()) {
2007 OS << "->";
2008 printID(getOptimized());
2009
2010 if (Optional<AliasResult> AR = getOptimizedAccessType())
2011 OS << " " << *AR;
2012 }
2013}
2014
2015void MemoryPhi::print(raw_ostream &OS) const {
2016 bool First = true;
2017 OS << getID() << " = MemoryPhi(";
2018 for (const auto &Op : operands()) {
2019 BasicBlock *BB = getIncomingBlock(Op);
2020 MemoryAccess *MA = cast<MemoryAccess>(Op);
2021 if (!First)
2022 OS << ',';
2023 else
2024 First = false;
2025
2026 OS << '{';
2027 if (BB->hasName())
2028 OS << BB->getName();
2029 else
2030 BB->printAsOperand(OS, false);
2031 OS << ',';
2032 if (unsigned ID = MA->getID())
2033 OS << ID;
2034 else
2035 OS << LiveOnEntryStr;
2036 OS << '}';
2037 }
2038 OS << ')';
2039}
2040
2041void MemoryUse::print(raw_ostream &OS) const {
2042 MemoryAccess *UO = getDefiningAccess();
2043 OS << "MemoryUse(";
2044 if (UO && UO->getID())
2045 OS << UO->getID();
2046 else
2047 OS << LiveOnEntryStr;
2048 OS << ')';
2049
2050 if (Optional<AliasResult> AR = getOptimizedAccessType())
2051 OS << " " << *AR;
2052}
2053
2054void MemoryAccess::dump() const {
2055// Cannot completely remove virtual function even in release mode.
2056#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
2057 print(dbgs());
2058 dbgs() << "\n";
2059#endif
2060}
2061
2062char MemorySSAPrinterLegacyPass::ID = 0;
2063
2064MemorySSAPrinterLegacyPass::MemorySSAPrinterLegacyPass() : FunctionPass(ID) {
2065 initializeMemorySSAPrinterLegacyPassPass(*PassRegistry::getPassRegistry());
2066}
2067
2068void MemorySSAPrinterLegacyPass::getAnalysisUsage(AnalysisUsage &AU) const {
2069 AU.setPreservesAll();
2070 AU.addRequired<MemorySSAWrapperPass>();
2071}
2072
2073bool MemorySSAPrinterLegacyPass::runOnFunction(Function &F) {
2074 auto &MSSA = getAnalysis<MemorySSAWrapperPass>().getMSSA();
2075 MSSA.print(dbgs());
2076 if (VerifyMemorySSA)
2077 MSSA.verifyMemorySSA();
2078 return false;
2079}
2080
2081AnalysisKey MemorySSAAnalysis::Key;
2082
2083MemorySSAAnalysis::Result MemorySSAAnalysis::run(Function &F,
2084 FunctionAnalysisManager &AM) {
2085 auto &DT = AM.getResult<DominatorTreeAnalysis>(F);
2086 auto &AA = AM.getResult<AAManager>(F);
2087 return MemorySSAAnalysis::Result(llvm::make_unique<MemorySSA>(F, &AA, &DT));
2088}
2089
2090PreservedAnalyses MemorySSAPrinterPass::run(Function &F,
2091 FunctionAnalysisManager &AM) {
2092 OS << "MemorySSA for function: " << F.getName() << "\n";
2093 AM.getResult<MemorySSAAnalysis>(F).getMSSA().print(OS);
2094
2095 return PreservedAnalyses::all();
2096}
2097
2098PreservedAnalyses MemorySSAVerifierPass::run(Function &F,
2099 FunctionAnalysisManager &AM) {
2100 AM.getResult<MemorySSAAnalysis>(F).getMSSA().verifyMemorySSA();
2101
2102 return PreservedAnalyses::all();
2103}
2104
2105char MemorySSAWrapperPass::ID = 0;
2106
2107MemorySSAWrapperPass::MemorySSAWrapperPass() : FunctionPass(ID) {
2108 initializeMemorySSAWrapperPassPass(*PassRegistry::getPassRegistry());
2109}
2110
2111void MemorySSAWrapperPass::releaseMemory() { MSSA.reset(); }
2112
2113void MemorySSAWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
2114 AU.setPreservesAll();
2115 AU.addRequiredTransitive<DominatorTreeWrapperPass>();
2116 AU.addRequiredTransitive<AAResultsWrapperPass>();
2117}
2118
2119bool MemorySSAWrapperPass::runOnFunction(Function &F) {
2120 auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
2121 auto &AA = getAnalysis<AAResultsWrapperPass>().getAAResults();
2122 MSSA.reset(new MemorySSA(F, &AA, &DT));
2123 return false;
2124}
2125
2126void MemorySSAWrapperPass::verifyAnalysis() const { MSSA->verifyMemorySSA(); }
1
Calling 'MemorySSA::verifyMemorySSA'
2127
2128void MemorySSAWrapperPass::print(raw_ostream &OS, const Module *M) const {
2129 MSSA->print(OS);
2130}
2131
2132MemorySSAWalker::MemorySSAWalker(MemorySSA *M) : MSSA(M) {}
2133
2134MemorySSA::CachingWalker::CachingWalker(MemorySSA *M, AliasAnalysis *A,
2135 DominatorTree *D)
2136 : MemorySSAWalker(M), Walker(*M, *A, *D) {}
2137
2138void MemorySSA::CachingWalker::invalidateInfo(MemoryAccess *MA) {
2139 if (auto *MUD = dyn_cast<MemoryUseOrDef>(MA))
2140 MUD->resetOptimized();
2141}
2142
2143/// Walk the use-def chains starting at \p MA and find
2144/// the MemoryAccess that actually clobbers Loc.
2145///
2146/// \returns our clobbering memory access
2147MemoryAccess *MemorySSA::CachingWalker::getClobberingMemoryAccess(
2148 MemoryAccess *StartingAccess, UpwardsMemoryQuery &Q) {
2149 return Walker.findClobber(StartingAccess, Q);
2150}
2151
2152MemoryAccess *MemorySSA::CachingWalker::getClobberingMemoryAccess(
2153 MemoryAccess *StartingAccess, const MemoryLocation &Loc) {
2154 if (isa<MemoryPhi>(StartingAccess))
2155 return StartingAccess;
2156
2157 auto *StartingUseOrDef = cast<MemoryUseOrDef>(StartingAccess);
2158 if (MSSA->isLiveOnEntryDef(StartingUseOrDef))
2159 return StartingUseOrDef;
2160
2161 Instruction *I = StartingUseOrDef->getMemoryInst();
2162
2163 // Conservatively, fences are always clobbers, so don't perform the walk if we
2164 // hit a fence.
2165 if (!ImmutableCallSite(I) && I->isFenceLike())
2166 return StartingUseOrDef;
2167
2168 UpwardsMemoryQuery Q;
2169 Q.OriginalAccess = StartingUseOrDef;
2170 Q.StartingLoc = Loc;
2171 Q.Inst = I;
2172 Q.IsCall = false;
2173
2174 // Unlike the other function, do not walk to the def of a def, because we are
2175 // handed something we already believe is the clobbering access.
2176 MemoryAccess *DefiningAccess = isa<MemoryUse>(StartingUseOrDef)
2177 ? StartingUseOrDef->getDefiningAccess()
2178 : StartingUseOrDef;
2179
2180 MemoryAccess *Clobber = getClobberingMemoryAccess(DefiningAccess, Q);
2181 LLVM_DEBUG(dbgs() << "Starting Memory SSA clobber for " << *I << " is ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "Starting Memory SSA clobber for "
<< *I << " is "; } } while (false)
;
2182 LLVM_DEBUG(dbgs() << *StartingUseOrDef << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << *StartingUseOrDef << "\n"
; } } while (false)
;
2183 LLVM_DEBUG(dbgs() << "Final Memory SSA clobber for " << *I << " is ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "Final Memory SSA clobber for "
<< *I << " is "; } } while (false)
;
2184 LLVM_DEBUG(dbgs() << *Clobber << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << *Clobber << "\n"; } } while
(false)
;
2185 return Clobber;
2186}
2187
2188MemoryAccess *
2189MemorySSA::CachingWalker::getClobberingMemoryAccess(MemoryAccess *MA) {
2190 auto *StartingAccess = dyn_cast<MemoryUseOrDef>(MA);
2191 // If this is a MemoryPhi, we can't do anything.
2192 if (!StartingAccess)
2193 return MA;
2194
2195 // If this is an already optimized use or def, return the optimized result.
2196 // Note: Currently, we store the optimized def result in a separate field,
2197 // since we can't use the defining access.
2198 if (StartingAccess->isOptimized())
2199 return StartingAccess->getOptimized();
2200
2201 const Instruction *I = StartingAccess->getMemoryInst();
2202 UpwardsMemoryQuery Q(I, StartingAccess);
2203 // We can't sanely do anything with a fence, since they conservatively clobber
2204 // all memory, and have no locations to get pointers from to try to
2205 // disambiguate.
2206 if (!Q.IsCall && I->isFenceLike())
2207 return StartingAccess;
2208
2209 if (isUseTriviallyOptimizableToLiveOnEntry(*MSSA->AA, I)) {
2210 MemoryAccess *LiveOnEntry = MSSA->getLiveOnEntryDef();
2211 StartingAccess->setOptimized(LiveOnEntry);
2212 StartingAccess->setOptimizedAccessType(None);
2213 return LiveOnEntry;
2214 }
2215
2216 // Start with the thing we already think clobbers this location
2217 MemoryAccess *DefiningAccess = StartingAccess->getDefiningAccess();
2218
2219 // At this point, DefiningAccess may be the live on entry def.
2220 // If it is, we will not get a better result.
2221 if (MSSA->isLiveOnEntryDef(DefiningAccess)) {
2222 StartingAccess->setOptimized(DefiningAccess);
2223 StartingAccess->setOptimizedAccessType(None);
2224 return DefiningAccess;
2225 }
2226
2227 MemoryAccess *Result = getClobberingMemoryAccess(DefiningAccess, Q);
2228 LLVM_DEBUG(dbgs() << "Starting Memory SSA clobber for " << *I << " is ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "Starting Memory SSA clobber for "
<< *I << " is "; } } while (false)
;
2229 LLVM_DEBUG(dbgs() << *DefiningAccess << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << *DefiningAccess << "\n"
; } } while (false)
;
2230 LLVM_DEBUG(dbgs() << "Final Memory SSA clobber for " << *I << " is ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << "Final Memory SSA clobber for "
<< *I << " is "; } } while (false)
;
2231 LLVM_DEBUG(dbgs() << *Result << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("memoryssa")) { dbgs() << *Result << "\n"; } } while
(false)
;
2232
2233 StartingAccess->setOptimized(Result);
2234 if (MSSA->isLiveOnEntryDef(Result))
2235 StartingAccess->setOptimizedAccessType(None);
2236 else if (Q.AR == MustAlias)
2237 StartingAccess->setOptimizedAccessType(MustAlias);
2238
2239 return Result;
2240}
2241
2242MemoryAccess *
2243DoNothingMemorySSAWalker::getClobberingMemoryAccess(MemoryAccess *MA) {
2244 if (auto *Use = dyn_cast<MemoryUseOrDef>(MA))
2245 return Use->getDefiningAccess();
2246 return MA;
2247}
2248
2249MemoryAccess *DoNothingMemorySSAWalker::getClobberingMemoryAccess(
2250 MemoryAccess *StartingAccess, const MemoryLocation &) {
2251 if (auto *Use = dyn_cast<MemoryUseOrDef>(StartingAccess))
2252 return Use->getDefiningAccess();
2253 return StartingAccess;
2254}
2255
2256void MemoryPhi::deleteMe(DerivedUser *Self) {
2257 delete static_cast<MemoryPhi *>(Self);
2258}
2259
2260void MemoryDef::deleteMe(DerivedUser *Self) {
2261 delete static_cast<MemoryDef *>(Self);
2262}
2263
2264void MemoryUse::deleteMe(DerivedUser *Self) {
2265 delete static_cast<MemoryUse *>(Self);
2266}

/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h

1//===- MemorySSA.h - Build Memory SSA ---------------------------*- C++ -*-===//
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/// \file
11/// This file exposes an interface to building/using memory SSA to
12/// walk memory instructions using a use/def graph.
13///
14/// Memory SSA class builds an SSA form that links together memory access
15/// instructions such as loads, stores, atomics, and calls. Additionally, it
16/// does a trivial form of "heap versioning" Every time the memory state changes
17/// in the program, we generate a new heap version. It generates
18/// MemoryDef/Uses/Phis that are overlayed on top of the existing instructions.
19///
20/// As a trivial example,
21/// define i32 @main() #0 {
22/// entry:
23/// %call = call noalias i8* @_Znwm(i64 4) #2
24/// %0 = bitcast i8* %call to i32*
25/// %call1 = call noalias i8* @_Znwm(i64 4) #2
26/// %1 = bitcast i8* %call1 to i32*
27/// store i32 5, i32* %0, align 4
28/// store i32 7, i32* %1, align 4
29/// %2 = load i32* %0, align 4
30/// %3 = load i32* %1, align 4
31/// %add = add nsw i32 %2, %3
32/// ret i32 %add
33/// }
34///
35/// Will become
36/// define i32 @main() #0 {
37/// entry:
38/// ; 1 = MemoryDef(0)
39/// %call = call noalias i8* @_Znwm(i64 4) #3
40/// %2 = bitcast i8* %call to i32*
41/// ; 2 = MemoryDef(1)
42/// %call1 = call noalias i8* @_Znwm(i64 4) #3
43/// %4 = bitcast i8* %call1 to i32*
44/// ; 3 = MemoryDef(2)
45/// store i32 5, i32* %2, align 4
46/// ; 4 = MemoryDef(3)
47/// store i32 7, i32* %4, align 4
48/// ; MemoryUse(3)
49/// %7 = load i32* %2, align 4
50/// ; MemoryUse(4)
51/// %8 = load i32* %4, align 4
52/// %add = add nsw i32 %7, %8
53/// ret i32 %add
54/// }
55///
56/// Given this form, all the stores that could ever effect the load at %8 can be
57/// gotten by using the MemoryUse associated with it, and walking from use to
58/// def until you hit the top of the function.
59///
60/// Each def also has a list of users associated with it, so you can walk from
61/// both def to users, and users to defs. Note that we disambiguate MemoryUses,
62/// but not the RHS of MemoryDefs. You can see this above at %7, which would
63/// otherwise be a MemoryUse(4). Being disambiguated means that for a given
64/// store, all the MemoryUses on its use lists are may-aliases of that store
65/// (but the MemoryDefs on its use list may not be).
66///
67/// MemoryDefs are not disambiguated because it would require multiple reaching
68/// definitions, which would require multiple phis, and multiple memoryaccesses
69/// per instruction.
70//
71//===----------------------------------------------------------------------===//
72
73#ifndef LLVM_ANALYSIS_MEMORYSSA_H
74#define LLVM_ANALYSIS_MEMORYSSA_H
75
76#include "llvm/ADT/DenseMap.h"
77#include "llvm/ADT/GraphTraits.h"
78#include "llvm/ADT/SmallPtrSet.h"
79#include "llvm/ADT/SmallVector.h"
80#include "llvm/ADT/ilist.h"
81#include "llvm/ADT/ilist_node.h"
82#include "llvm/ADT/iterator.h"
83#include "llvm/ADT/iterator_range.h"
84#include "llvm/ADT/simple_ilist.h"
85#include "llvm/Analysis/AliasAnalysis.h"
86#include "llvm/Analysis/MemoryLocation.h"
87#include "llvm/Analysis/PHITransAddr.h"
88#include "llvm/IR/BasicBlock.h"
89#include "llvm/IR/DerivedUser.h"
90#include "llvm/IR/Dominators.h"
91#include "llvm/IR/Module.h"
92#include "llvm/IR/Type.h"
93#include "llvm/IR/Use.h"
94#include "llvm/IR/User.h"
95#include "llvm/IR/Value.h"
96#include "llvm/IR/ValueHandle.h"
97#include "llvm/Pass.h"
98#include "llvm/Support/Casting.h"
99#include <algorithm>
100#include <cassert>
101#include <cstddef>
102#include <iterator>
103#include <memory>
104#include <utility>
105
106namespace llvm {
107
108class Function;
109class Instruction;
110class MemoryAccess;
111class MemorySSAWalker;
112class LLVMContext;
113class raw_ostream;
114
115namespace MSSAHelpers {
116
117struct AllAccessTag {};
118struct DefsOnlyTag {};
119
120} // end namespace MSSAHelpers
121
122enum : unsigned {
123 // Used to signify what the default invalid ID is for MemoryAccess's
124 // getID()
125 INVALID_MEMORYACCESS_ID = -1U
126};
127
128template <class T> class memoryaccess_def_iterator_base;
129using memoryaccess_def_iterator = memoryaccess_def_iterator_base<MemoryAccess>;
130using const_memoryaccess_def_iterator =
131 memoryaccess_def_iterator_base<const MemoryAccess>;
132
133// The base for all memory accesses. All memory accesses in a block are
134// linked together using an intrusive list.
135class MemoryAccess
136 : public DerivedUser,
137 public ilist_node<MemoryAccess, ilist_tag<MSSAHelpers::AllAccessTag>>,
138 public ilist_node<MemoryAccess, ilist_tag<MSSAHelpers::DefsOnlyTag>> {
139public:
140 using AllAccessType =
141 ilist_node<MemoryAccess, ilist_tag<MSSAHelpers::AllAccessTag>>;
142 using DefsOnlyType =
143 ilist_node<MemoryAccess, ilist_tag<MSSAHelpers::DefsOnlyTag>>;
144
145 MemoryAccess(const MemoryAccess &) = delete;
146 MemoryAccess &operator=(const MemoryAccess &) = delete;
147
148 void *operator new(size_t) = delete;
149
150 // Methods for support type inquiry through isa, cast, and
151 // dyn_cast
152 static bool classof(const Value *V) {
153 unsigned ID = V->getValueID();
154 return ID == MemoryUseVal || ID == MemoryPhiVal || ID == MemoryDefVal;
155 }
156
157 BasicBlock *getBlock() const { return Block; }
158
159 void print(raw_ostream &OS) const;
160 void dump() const;
161
162 /// The user iterators for a memory access
163 using iterator = user_iterator;
164 using const_iterator = const_user_iterator;
165
166 /// This iterator walks over all of the defs in a given
167 /// MemoryAccess. For MemoryPhi nodes, this walks arguments. For
168 /// MemoryUse/MemoryDef, this walks the defining access.
169 memoryaccess_def_iterator defs_begin();
170 const_memoryaccess_def_iterator defs_begin() const;
171 memoryaccess_def_iterator defs_end();
172 const_memoryaccess_def_iterator defs_end() const;
173
174 /// Get the iterators for the all access list and the defs only list
175 /// We default to the all access list.
176 AllAccessType::self_iterator getIterator() {
177 return this->AllAccessType::getIterator();
178 }
179 AllAccessType::const_self_iterator getIterator() const {
180 return this->AllAccessType::getIterator();
181 }
182 AllAccessType::reverse_self_iterator getReverseIterator() {
183 return this->AllAccessType::getReverseIterator();
184 }
185 AllAccessType::const_reverse_self_iterator getReverseIterator() const {
186 return this->AllAccessType::getReverseIterator();
187 }
188 DefsOnlyType::self_iterator getDefsIterator() {
189 return this->DefsOnlyType::getIterator();
190 }
191 DefsOnlyType::const_self_iterator getDefsIterator() const {
192 return this->DefsOnlyType::getIterator();
193 }
194 DefsOnlyType::reverse_self_iterator getReverseDefsIterator() {
195 return this->DefsOnlyType::getReverseIterator();
196 }
197 DefsOnlyType::const_reverse_self_iterator getReverseDefsIterator() const {
198 return this->DefsOnlyType::getReverseIterator();
199 }
200
201protected:
202 friend class MemoryDef;
203 friend class MemoryPhi;
204 friend class MemorySSA;
205 friend class MemoryUse;
206 friend class MemoryUseOrDef;
207
208 /// Used by MemorySSA to change the block of a MemoryAccess when it is
209 /// moved.
210 void setBlock(BasicBlock *BB) { Block = BB; }
211
212 /// Used for debugging and tracking things about MemoryAccesses.
213 /// Guaranteed unique among MemoryAccesses, no guarantees otherwise.
214 inline unsigned getID() const;
215
216 MemoryAccess(LLVMContext &C, unsigned Vty, DeleteValueTy DeleteValue,
217 BasicBlock *BB, unsigned NumOperands)
218 : DerivedUser(Type::getVoidTy(C), Vty, nullptr, NumOperands, DeleteValue),
219 Block(BB) {}
220
221 // Use deleteValue() to delete a generic MemoryAccess.
222 ~MemoryAccess() = default;
223
224private:
225 BasicBlock *Block;
226};
227
228template <>
229struct ilist_alloc_traits<MemoryAccess> {
230 static void deleteNode(MemoryAccess *MA) { MA->deleteValue(); }
231};
232
233inline raw_ostream &operator<<(raw_ostream &OS, const MemoryAccess &MA) {
234 MA.print(OS);
235 return OS;
236}
237
238/// Class that has the common methods + fields of memory uses/defs. It's
239/// a little awkward to have, but there are many cases where we want either a
240/// use or def, and there are many cases where uses are needed (defs aren't
241/// acceptable), and vice-versa.
242///
243/// This class should never be instantiated directly; make a MemoryUse or
244/// MemoryDef instead.
245class MemoryUseOrDef : public MemoryAccess {
246public:
247 void *operator new(size_t) = delete;
248
249 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(MemoryAccess)public: inline MemoryAccess *getOperand(unsigned) const; inline
void setOperand(unsigned, MemoryAccess*); inline op_iterator
op_begin(); inline const_op_iterator op_begin() const; inline
op_iterator op_end(); inline const_op_iterator op_end() const
; protected: template <int> inline Use &Op(); template
<int> inline const Use &Op() const; public: inline
unsigned getNumOperands() const
;
250
251 /// Get the instruction that this MemoryUse represents.
252 Instruction *getMemoryInst() const { return MemoryInstruction; }
253
254 /// Get the access that produces the memory state used by this Use.
255 MemoryAccess *getDefiningAccess() const { return getOperand(0); }
256
257 static bool classof(const Value *MA) {
258 return MA->getValueID() == MemoryUseVal || MA->getValueID() == MemoryDefVal;
259 }
260
261 // Sadly, these have to be public because they are needed in some of the
262 // iterators.
263 inline bool isOptimized() const;
264 inline MemoryAccess *getOptimized() const;
265 inline void setOptimized(MemoryAccess *);
266
267 // Retrieve AliasResult type of the optimized access. Ideally this would be
268 // returned by the caching walker and may go away in the future.
269 Optional<AliasResult> getOptimizedAccessType() const {
270 return OptimizedAccessAlias;
271 }
272
273 /// Reset the ID of what this MemoryUse was optimized to, causing it to
274 /// be rewalked by the walker if necessary.
275 /// This really should only be called by tests.
276 inline void resetOptimized();
277
278protected:
279 friend class MemorySSA;
280 friend class MemorySSAUpdater;
281
282 MemoryUseOrDef(LLVMContext &C, MemoryAccess *DMA, unsigned Vty,
283 DeleteValueTy DeleteValue, Instruction *MI, BasicBlock *BB,
284 unsigned NumOperands)
285 : MemoryAccess(C, Vty, DeleteValue, BB, NumOperands),
286 MemoryInstruction(MI), OptimizedAccessAlias(MayAlias) {
287 setDefiningAccess(DMA);
288 }
289
290 // Use deleteValue() to delete a generic MemoryUseOrDef.
291 ~MemoryUseOrDef() = default;
292
293 void setOptimizedAccessType(Optional<AliasResult> AR) {
294 OptimizedAccessAlias = AR;
295 }
296
297 void setDefiningAccess(MemoryAccess *DMA, bool Optimized = false,
298 Optional<AliasResult> AR = MayAlias) {
299 if (!Optimized) {
300 setOperand(0, DMA);
301 return;
302 }
303 setOptimized(DMA);
304 setOptimizedAccessType(AR);
305 }
306
307private:
308 Instruction *MemoryInstruction;
309 Optional<AliasResult> OptimizedAccessAlias;
310};
311
312/// Represents read-only accesses to memory
313///
314/// In particular, the set of Instructions that will be represented by
315/// MemoryUse's is exactly the set of Instructions for which
316/// AliasAnalysis::getModRefInfo returns "Ref".
317class MemoryUse final : public MemoryUseOrDef {
318public:
319 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(MemoryAccess)public: inline MemoryAccess *getOperand(unsigned) const; inline
void setOperand(unsigned, MemoryAccess*); inline op_iterator
op_begin(); inline const_op_iterator op_begin() const; inline
op_iterator op_end(); inline const_op_iterator op_end() const
; protected: template <int> inline Use &Op(); template
<int> inline const Use &Op() const; public: inline
unsigned getNumOperands() const
;
320
321 MemoryUse(LLVMContext &C, MemoryAccess *DMA, Instruction *MI, BasicBlock *BB)
322 : MemoryUseOrDef(C, DMA, MemoryUseVal, deleteMe, MI, BB,
323 /*NumOperands=*/1) {}
324
325 // allocate space for exactly one operand
326 void *operator new(size_t s) { return User::operator new(s, 1); }
327
328 static bool classof(const Value *MA) {
329 return MA->getValueID() == MemoryUseVal;
330 }
331
332 void print(raw_ostream &OS) const;
333
334 void setOptimized(MemoryAccess *DMA) {
335 OptimizedID = DMA->getID();
336 setOperand(0, DMA);
337 }
338
339 bool isOptimized() const {
340 return getDefiningAccess() && OptimizedID == getDefiningAccess()->getID();
341 }
342
343 MemoryAccess *getOptimized() const {
344 return getDefiningAccess();
345 }
346
347 void resetOptimized() {
348 OptimizedID = INVALID_MEMORYACCESS_ID;
349 }
350
351protected:
352 friend class MemorySSA;
353
354private:
355 static void deleteMe(DerivedUser *Self);
356
357 unsigned OptimizedID = INVALID_MEMORYACCESS_ID;
358};
359
360template <>
361struct OperandTraits<MemoryUse> : public FixedNumOperandTraits<MemoryUse, 1> {};
362DEFINE_TRANSPARENT_OPERAND_ACCESSORS(MemoryUse, MemoryAccess)MemoryUse::op_iterator MemoryUse::op_begin() { return OperandTraits
<MemoryUse>::op_begin(this); } MemoryUse::const_op_iterator
MemoryUse::op_begin() const { return OperandTraits<MemoryUse
>::op_begin(const_cast<MemoryUse*>(this)); } MemoryUse
::op_iterator MemoryUse::op_end() { return OperandTraits<MemoryUse
>::op_end(this); } MemoryUse::const_op_iterator MemoryUse::
op_end() const { return OperandTraits<MemoryUse>::op_end
(const_cast<MemoryUse*>(this)); } MemoryAccess *MemoryUse
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
OperandTraits<MemoryUse>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryUse>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 362, __PRETTY_FUNCTION__)); return cast_or_null<MemoryAccess
>( OperandTraits<MemoryUse>::op_begin(const_cast<
MemoryUse*>(this))[i_nocapture].get()); } void MemoryUse::
setOperand(unsigned i_nocapture, MemoryAccess *Val_nocapture)
{ ((i_nocapture < OperandTraits<MemoryUse>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryUse>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 362, __PRETTY_FUNCTION__)); OperandTraits<MemoryUse>::
op_begin(this)[i_nocapture] = Val_nocapture; } unsigned MemoryUse
::getNumOperands() const { return OperandTraits<MemoryUse>
::operands(this); } template <int Idx_nocapture> Use &
MemoryUse::Op() { return this->OpFrom<Idx_nocapture>
(this); } template <int Idx_nocapture> const Use &MemoryUse
::Op() const { return this->OpFrom<Idx_nocapture>(this
); }
363
364/// Represents a read-write access to memory, whether it is a must-alias,
365/// or a may-alias.
366///
367/// In particular, the set of Instructions that will be represented by
368/// MemoryDef's is exactly the set of Instructions for which
369/// AliasAnalysis::getModRefInfo returns "Mod" or "ModRef".
370/// Note that, in order to provide def-def chains, all defs also have a use
371/// associated with them. This use points to the nearest reaching
372/// MemoryDef/MemoryPhi.
373class MemoryDef final : public MemoryUseOrDef {
374public:
375 friend class MemorySSA;
376
377 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(MemoryAccess)public: inline MemoryAccess *getOperand(unsigned) const; inline
void setOperand(unsigned, MemoryAccess*); inline op_iterator
op_begin(); inline const_op_iterator op_begin() const; inline
op_iterator op_end(); inline const_op_iterator op_end() const
; protected: template <int> inline Use &Op(); template
<int> inline const Use &Op() const; public: inline
unsigned getNumOperands() const
;
378
379 MemoryDef(LLVMContext &C, MemoryAccess *DMA, Instruction *MI, BasicBlock *BB,
380 unsigned Ver)
381 : MemoryUseOrDef(C, DMA, MemoryDefVal, deleteMe, MI, BB,
382 /*NumOperands=*/2),
383 ID(Ver) {}
384
385 // allocate space for exactly two operands
386 void *operator new(size_t s) { return User::operator new(s, 2); }
387
388 static bool classof(const Value *MA) {
389 return MA->getValueID() == MemoryDefVal;
390 }
391
392 void setOptimized(MemoryAccess *MA) {
393 setOperand(1, MA);
394 OptimizedID = MA->getID();
395 }
396
397 MemoryAccess *getOptimized() const {
398 return cast_or_null<MemoryAccess>(getOperand(1));
399 }
400
401 bool isOptimized() const {
402 return getOptimized() && OptimizedID == getOptimized()->getID();
403 }
404
405 void resetOptimized() {
406 OptimizedID = INVALID_MEMORYACCESS_ID;
407 }
408
409 void print(raw_ostream &OS) const;
410
411 unsigned getID() const { return ID; }
412
413private:
414 static void deleteMe(DerivedUser *Self);
415
416 const unsigned ID;
417 unsigned OptimizedID = INVALID_MEMORYACCESS_ID;
418};
419
420template <>
421struct OperandTraits<MemoryDef> : public FixedNumOperandTraits<MemoryDef, 2> {};
422DEFINE_TRANSPARENT_OPERAND_ACCESSORS(MemoryDef, MemoryAccess)MemoryDef::op_iterator MemoryDef::op_begin() { return OperandTraits
<MemoryDef>::op_begin(this); } MemoryDef::const_op_iterator
MemoryDef::op_begin() const { return OperandTraits<MemoryDef
>::op_begin(const_cast<MemoryDef*>(this)); } MemoryDef
::op_iterator MemoryDef::op_end() { return OperandTraits<MemoryDef
>::op_end(this); } MemoryDef::const_op_iterator MemoryDef::
op_end() const { return OperandTraits<MemoryDef>::op_end
(const_cast<MemoryDef*>(this)); } MemoryAccess *MemoryDef
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
OperandTraits<MemoryDef>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryDef>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 422, __PRETTY_FUNCTION__)); return cast_or_null<MemoryAccess
>( OperandTraits<MemoryDef>::op_begin(const_cast<
MemoryDef*>(this))[i_nocapture].get()); } void MemoryDef::
setOperand(unsigned i_nocapture, MemoryAccess *Val_nocapture)
{ ((i_nocapture < OperandTraits<MemoryDef>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryDef>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 422, __PRETTY_FUNCTION__)); OperandTraits<MemoryDef>::
op_begin(this)[i_nocapture] = Val_nocapture; } unsigned MemoryDef
::getNumOperands() const { return OperandTraits<MemoryDef>
::operands(this); } template <int Idx_nocapture> Use &
MemoryDef::Op() { return this->OpFrom<Idx_nocapture>
(this); } template <int Idx_nocapture> const Use &MemoryDef
::Op() const { return this->OpFrom<Idx_nocapture>(this
); }
423
424template <>
425struct OperandTraits<MemoryUseOrDef> {
426 static Use *op_begin(MemoryUseOrDef *MUD) {
427 if (auto *MU = dyn_cast<MemoryUse>(MUD))
428 return OperandTraits<MemoryUse>::op_begin(MU);
429 return OperandTraits<MemoryDef>::op_begin(cast<MemoryDef>(MUD));
430 }
431
432 static Use *op_end(MemoryUseOrDef *MUD) {
433 if (auto *MU = dyn_cast<MemoryUse>(MUD))
434 return OperandTraits<MemoryUse>::op_end(MU);
435 return OperandTraits<MemoryDef>::op_end(cast<MemoryDef>(MUD));
436 }
437
438 static unsigned operands(const MemoryUseOrDef *MUD) {
439 if (const auto *MU = dyn_cast<MemoryUse>(MUD))
440 return OperandTraits<MemoryUse>::operands(MU);
441 return OperandTraits<MemoryDef>::operands(cast<MemoryDef>(MUD));
442 }
443};
444DEFINE_TRANSPARENT_OPERAND_ACCESSORS(MemoryUseOrDef, MemoryAccess)MemoryUseOrDef::op_iterator MemoryUseOrDef::op_begin() { return
OperandTraits<MemoryUseOrDef>::op_begin(this); } MemoryUseOrDef
::const_op_iterator MemoryUseOrDef::op_begin() const { return
OperandTraits<MemoryUseOrDef>::op_begin(const_cast<
MemoryUseOrDef*>(this)); } MemoryUseOrDef::op_iterator MemoryUseOrDef
::op_end() { return OperandTraits<MemoryUseOrDef>::op_end
(this); } MemoryUseOrDef::const_op_iterator MemoryUseOrDef::op_end
() const { return OperandTraits<MemoryUseOrDef>::op_end
(const_cast<MemoryUseOrDef*>(this)); } MemoryAccess *MemoryUseOrDef
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
OperandTraits<MemoryUseOrDef>::operands(this) &&
"getOperand() out of range!") ? static_cast<void> (0) :
__assert_fail ("i_nocapture < OperandTraits<MemoryUseOrDef>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 444, __PRETTY_FUNCTION__)); return cast_or_null<MemoryAccess
>( OperandTraits<MemoryUseOrDef>::op_begin(const_cast
<MemoryUseOrDef*>(this))[i_nocapture].get()); } void MemoryUseOrDef
::setOperand(unsigned i_nocapture, MemoryAccess *Val_nocapture
) { ((i_nocapture < OperandTraits<MemoryUseOrDef>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryUseOrDef>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 444, __PRETTY_FUNCTION__)); OperandTraits<MemoryUseOrDef
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
MemoryUseOrDef::getNumOperands() const { return OperandTraits
<MemoryUseOrDef>::operands(this); } template <int Idx_nocapture
> Use &MemoryUseOrDef::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
const Use &MemoryUseOrDef::Op() const { return this->
OpFrom<Idx_nocapture>(this); }
445
446/// Represents phi nodes for memory accesses.
447///
448/// These have the same semantic as regular phi nodes, with the exception that
449/// only one phi will ever exist in a given basic block.
450/// Guaranteeing one phi per block means guaranteeing there is only ever one
451/// valid reaching MemoryDef/MemoryPHI along each path to the phi node.
452/// This is ensured by not allowing disambiguation of the RHS of a MemoryDef or
453/// a MemoryPhi's operands.
454/// That is, given
455/// if (a) {
456/// store %a
457/// store %b
458/// }
459/// it *must* be transformed into
460/// if (a) {
461/// 1 = MemoryDef(liveOnEntry)
462/// store %a
463/// 2 = MemoryDef(1)
464/// store %b
465/// }
466/// and *not*
467/// if (a) {
468/// 1 = MemoryDef(liveOnEntry)
469/// store %a
470/// 2 = MemoryDef(liveOnEntry)
471/// store %b
472/// }
473/// even if the two stores do not conflict. Otherwise, both 1 and 2 reach the
474/// end of the branch, and if there are not two phi nodes, one will be
475/// disconnected completely from the SSA graph below that point.
476/// Because MemoryUse's do not generate new definitions, they do not have this
477/// issue.
478class MemoryPhi final : public MemoryAccess {
479 // allocate space for exactly zero operands
480 void *operator new(size_t s) { return User::operator new(s); }
481
482public:
483 /// Provide fast operand accessors
484 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(MemoryAccess)public: inline MemoryAccess *getOperand(unsigned) const; inline
void setOperand(unsigned, MemoryAccess*); inline op_iterator
op_begin(); inline const_op_iterator op_begin() const; inline
op_iterator op_end(); inline const_op_iterator op_end() const
; protected: template <int> inline Use &Op(); template
<int> inline const Use &Op() const; public: inline
unsigned getNumOperands() const
;
485
486 MemoryPhi(LLVMContext &C, BasicBlock *BB, unsigned Ver, unsigned NumPreds = 0)
487 : MemoryAccess(C, MemoryPhiVal, deleteMe, BB, 0), ID(Ver),
488 ReservedSpace(NumPreds) {
489 allocHungoffUses(ReservedSpace);
490 }
491
492 // Block iterator interface. This provides access to the list of incoming
493 // basic blocks, which parallels the list of incoming values.
494 using block_iterator = BasicBlock **;
495 using const_block_iterator = BasicBlock *const *;
496
497 block_iterator block_begin() {
498 auto *Ref = reinterpret_cast<Use::UserRef *>(op_begin() + ReservedSpace);
499 return reinterpret_cast<block_iterator>(Ref + 1);
500 }
501
502 const_block_iterator block_begin() const {
503 const auto *Ref =
504 reinterpret_cast<const Use::UserRef *>(op_begin() + ReservedSpace);
505 return reinterpret_cast<const_block_iterator>(Ref + 1);
506 }
507
508 block_iterator block_end() { return block_begin() + getNumOperands(); }
509
510 const_block_iterator block_end() const {
511 return block_begin() + getNumOperands();
512 }
513
514 iterator_range<block_iterator> blocks() {
515 return make_range(block_begin(), block_end());
516 }
517
518 iterator_range<const_block_iterator> blocks() const {
519 return make_range(block_begin(), block_end());
520 }
521
522 op_range incoming_values() { return operands(); }
523
524 const_op_range incoming_values() const { return operands(); }
525
526 /// Return the number of incoming edges
527 unsigned getNumIncomingValues() const { return getNumOperands(); }
528
529 /// Return incoming value number x
530 MemoryAccess *getIncomingValue(unsigned I) const { return getOperand(I); }
531 void setIncomingValue(unsigned I, MemoryAccess *V) {
532 assert(V && "PHI node got a null value!")((V && "PHI node got a null value!") ? static_cast<
void> (0) : __assert_fail ("V && \"PHI node got a null value!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 532, __PRETTY_FUNCTION__))
;
533 setOperand(I, V);
534 }
535
536 static unsigned getOperandNumForIncomingValue(unsigned I) { return I; }
537 static unsigned getIncomingValueNumForOperand(unsigned I) { return I; }
538
539 /// Return incoming basic block number @p i.
540 BasicBlock *getIncomingBlock(unsigned I) const { return block_begin()[I]; }
541
542 /// Return incoming basic block corresponding
543 /// to an operand of the PHI.
544 BasicBlock *getIncomingBlock(const Use &U) const {
545 assert(this == U.getUser() && "Iterator doesn't point to PHI's Uses?")((this == U.getUser() && "Iterator doesn't point to PHI's Uses?"
) ? static_cast<void> (0) : __assert_fail ("this == U.getUser() && \"Iterator doesn't point to PHI's Uses?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 545, __PRETTY_FUNCTION__))
;
546 return getIncomingBlock(unsigned(&U - op_begin()));
547 }
548
549 /// Return incoming basic block corresponding
550 /// to value use iterator.
551 BasicBlock *getIncomingBlock(MemoryAccess::const_user_iterator I) const {
552 return getIncomingBlock(I.getUse());
553 }
554
555 void setIncomingBlock(unsigned I, BasicBlock *BB) {
556 assert(BB && "PHI node got a null basic block!")((BB && "PHI node got a null basic block!") ? static_cast
<void> (0) : __assert_fail ("BB && \"PHI node got a null basic block!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 556, __PRETTY_FUNCTION__))
;
557 block_begin()[I] = BB;
558 }
559
560 /// Add an incoming value to the end of the PHI list
561 void addIncoming(MemoryAccess *V, BasicBlock *BB) {
562 if (getNumOperands() == ReservedSpace)
563 growOperands(); // Get more space!
564 // Initialize some new operands.
565 setNumHungOffUseOperands(getNumOperands() + 1);
566 setIncomingValue(getNumOperands() - 1, V);
567 setIncomingBlock(getNumOperands() - 1, BB);
568 }
569
570 /// Return the first index of the specified basic
571 /// block in the value list for this PHI. Returns -1 if no instance.
572 int getBasicBlockIndex(const BasicBlock *BB) const {
573 for (unsigned I = 0, E = getNumOperands(); I != E; ++I)
574 if (block_begin()[I] == BB)
575 return I;
576 return -1;
577 }
578
579 MemoryAccess *getIncomingValueForBlock(const BasicBlock *BB) const {
580 int Idx = getBasicBlockIndex(BB);
581 assert(Idx >= 0 && "Invalid basic block argument!")((Idx >= 0 && "Invalid basic block argument!") ? static_cast
<void> (0) : __assert_fail ("Idx >= 0 && \"Invalid basic block argument!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 581, __PRETTY_FUNCTION__))
;
582 return getIncomingValue(Idx);
583 }
584
585 // After deleting incoming position I, the order of incoming may be changed.
586 void unorderedDeleteIncoming(unsigned I) {
587 unsigned E = getNumOperands();
588 assert(I < E && "Cannot remove out of bounds Phi entry.")((I < E && "Cannot remove out of bounds Phi entry."
) ? static_cast<void> (0) : __assert_fail ("I < E && \"Cannot remove out of bounds Phi entry.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 588, __PRETTY_FUNCTION__))
;
589 // MemoryPhi must have at least two incoming values, otherwise the MemoryPhi
590 // itself should be deleted.
591 assert(E >= 2 && "Cannot only remove incoming values in MemoryPhis with "((E >= 2 && "Cannot only remove incoming values in MemoryPhis with "
"at least 2 values.") ? static_cast<void> (0) : __assert_fail
("E >= 2 && \"Cannot only remove incoming values in MemoryPhis with \" \"at least 2 values.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 592, __PRETTY_FUNCTION__))
592 "at least 2 values.")((E >= 2 && "Cannot only remove incoming values in MemoryPhis with "
"at least 2 values.") ? static_cast<void> (0) : __assert_fail
("E >= 2 && \"Cannot only remove incoming values in MemoryPhis with \" \"at least 2 values.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 592, __PRETTY_FUNCTION__))
;
593 setIncomingValue(I, getIncomingValue(E - 1));
594 setIncomingBlock(I, block_begin()[E - 1]);
595 setOperand(E - 1, nullptr);
596 block_begin()[E - 1] = nullptr;
597 setNumHungOffUseOperands(getNumOperands() - 1);
598 }
599
600 // After deleting entries that satisfy Pred, remaining entries may have
601 // changed order.
602 template <typename Fn> void unorderedDeleteIncomingIf(Fn &&Pred) {
603 for (unsigned I = 0, E = getNumOperands(); I != E; ++I)
604 if (Pred(getIncomingValue(I), getIncomingBlock(I))) {
605 unorderedDeleteIncoming(I);
606 E = getNumOperands();
607 --I;
608 }
609 assert(getNumOperands() >= 1 &&((getNumOperands() >= 1 && "Cannot remove all incoming blocks in a MemoryPhi."
) ? static_cast<void> (0) : __assert_fail ("getNumOperands() >= 1 && \"Cannot remove all incoming blocks in a MemoryPhi.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 610, __PRETTY_FUNCTION__))
610 "Cannot remove all incoming blocks in a MemoryPhi.")((getNumOperands() >= 1 && "Cannot remove all incoming blocks in a MemoryPhi."
) ? static_cast<void> (0) : __assert_fail ("getNumOperands() >= 1 && \"Cannot remove all incoming blocks in a MemoryPhi.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 610, __PRETTY_FUNCTION__))
;
611 }
612
613 // After deleting incoming block BB, the incoming blocks order may be changed.
614 void unorderedDeleteIncomingBlock(const BasicBlock *BB) {
615 unorderedDeleteIncomingIf(
616 [&](const MemoryAccess *, const BasicBlock *B) { return BB == B; });
617 }
618
619 // After deleting incoming memory access MA, the incoming accesses order may
620 // be changed.
621 void unorderedDeleteIncomingValue(const MemoryAccess *MA) {
622 unorderedDeleteIncomingIf(
623 [&](const MemoryAccess *M, const BasicBlock *) { return MA == M; });
624 }
625
626 static bool classof(const Value *V) {
627 return V->getValueID() == MemoryPhiVal;
628 }
629
630 void print(raw_ostream &OS) const;
631
632 unsigned getID() const { return ID; }
633
634protected:
635 friend class MemorySSA;
636
637 /// this is more complicated than the generic
638 /// User::allocHungoffUses, because we have to allocate Uses for the incoming
639 /// values and pointers to the incoming blocks, all in one allocation.
640 void allocHungoffUses(unsigned N) {
641 User::allocHungoffUses(N, /* IsPhi */ true);
642 }
643
644private:
645 // For debugging only
646 const unsigned ID;
647 unsigned ReservedSpace;
648
649 /// This grows the operand list in response to a push_back style of
650 /// operation. This grows the number of ops by 1.5 times.
651 void growOperands() {
652 unsigned E = getNumOperands();
653 // 2 op PHI nodes are VERY common, so reserve at least enough for that.
654 ReservedSpace = std::max(E + E / 2, 2u);
655 growHungoffUses(ReservedSpace, /* IsPhi */ true);
656 }
657
658 static void deleteMe(DerivedUser *Self);
659};
660
661inline unsigned MemoryAccess::getID() const {
662 assert((isa<MemoryDef>(this) || isa<MemoryPhi>(this)) &&(((isa<MemoryDef>(this) || isa<MemoryPhi>(this)) &&
"only memory defs and phis have ids") ? static_cast<void>
(0) : __assert_fail ("(isa<MemoryDef>(this) || isa<MemoryPhi>(this)) && \"only memory defs and phis have ids\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 663, __PRETTY_FUNCTION__))
663 "only memory defs and phis have ids")(((isa<MemoryDef>(this) || isa<MemoryPhi>(this)) &&
"only memory defs and phis have ids") ? static_cast<void>
(0) : __assert_fail ("(isa<MemoryDef>(this) || isa<MemoryPhi>(this)) && \"only memory defs and phis have ids\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 663, __PRETTY_FUNCTION__))
;
664 if (const auto *MD = dyn_cast<MemoryDef>(this))
665 return MD->getID();
666 return cast<MemoryPhi>(this)->getID();
667}
668
669inline bool MemoryUseOrDef::isOptimized() const {
670 if (const auto *MD = dyn_cast<MemoryDef>(this))
671 return MD->isOptimized();
672 return cast<MemoryUse>(this)->isOptimized();
673}
674
675inline MemoryAccess *MemoryUseOrDef::getOptimized() const {
676 if (const auto *MD = dyn_cast<MemoryDef>(this))
677 return MD->getOptimized();
678 return cast<MemoryUse>(this)->getOptimized();
679}
680
681inline void MemoryUseOrDef::setOptimized(MemoryAccess *MA) {
682 if (auto *MD = dyn_cast<MemoryDef>(this))
683 MD->setOptimized(MA);
684 else
685 cast<MemoryUse>(this)->setOptimized(MA);
686}
687
688inline void MemoryUseOrDef::resetOptimized() {
689 if (auto *MD = dyn_cast<MemoryDef>(this))
690 MD->resetOptimized();
691 else
692 cast<MemoryUse>(this)->resetOptimized();
693}
694
695template <> struct OperandTraits<MemoryPhi> : public HungoffOperandTraits<2> {};
696DEFINE_TRANSPARENT_OPERAND_ACCESSORS(MemoryPhi, MemoryAccess)MemoryPhi::op_iterator MemoryPhi::op_begin() { return OperandTraits
<MemoryPhi>::op_begin(this); } MemoryPhi::const_op_iterator
MemoryPhi::op_begin() const { return OperandTraits<MemoryPhi
>::op_begin(const_cast<MemoryPhi*>(this)); } MemoryPhi
::op_iterator MemoryPhi::op_end() { return OperandTraits<MemoryPhi
>::op_end(this); } MemoryPhi::const_op_iterator MemoryPhi::
op_end() const { return OperandTraits<MemoryPhi>::op_end
(const_cast<MemoryPhi*>(this)); } MemoryAccess *MemoryPhi
::getOperand(unsigned i_nocapture) const { ((i_nocapture <
OperandTraits<MemoryPhi>::operands(this) && "getOperand() out of range!"
) ? static_cast<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryPhi>::operands(this) && \"getOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 696, __PRETTY_FUNCTION__)); return cast_or_null<MemoryAccess
>( OperandTraits<MemoryPhi>::op_begin(const_cast<
MemoryPhi*>(this))[i_nocapture].get()); } void MemoryPhi::
setOperand(unsigned i_nocapture, MemoryAccess *Val_nocapture)
{ ((i_nocapture < OperandTraits<MemoryPhi>::operands
(this) && "setOperand() out of range!") ? static_cast
<void> (0) : __assert_fail ("i_nocapture < OperandTraits<MemoryPhi>::operands(this) && \"setOperand() out of range!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 696, __PRETTY_FUNCTION__)); OperandTraits<MemoryPhi>::
op_begin(this)[i_nocapture] = Val_nocapture; } unsigned MemoryPhi
::getNumOperands() const { return OperandTraits<MemoryPhi>
::operands(this); } template <int Idx_nocapture> Use &
MemoryPhi::Op() { return this->OpFrom<Idx_nocapture>
(this); } template <int Idx_nocapture> const Use &MemoryPhi
::Op() const { return this->OpFrom<Idx_nocapture>(this
); }
697
698/// Encapsulates MemorySSA, including all data associated with memory
699/// accesses.
700class MemorySSA {
701public:
702 MemorySSA(Function &, AliasAnalysis *, DominatorTree *);
703 ~MemorySSA();
704
705 MemorySSAWalker *getWalker();
706
707 /// Given a memory Mod/Ref'ing instruction, get the MemorySSA
708 /// access associated with it. If passed a basic block gets the memory phi
709 /// node that exists for that block, if there is one. Otherwise, this will get
710 /// a MemoryUseOrDef.
711 MemoryUseOrDef *getMemoryAccess(const Instruction *I) const {
712 return cast_or_null<MemoryUseOrDef>(ValueToMemoryAccess.lookup(I));
713 }
714
715 MemoryPhi *getMemoryAccess(const BasicBlock *BB) const {
716 return cast_or_null<MemoryPhi>(ValueToMemoryAccess.lookup(cast<Value>(BB)));
717 }
718
719 void dump() const;
720 void print(raw_ostream &) const;
721
722 /// Return true if \p MA represents the live on entry value
723 ///
724 /// Loads and stores from pointer arguments and other global values may be
725 /// defined by memory operations that do not occur in the current function, so
726 /// they may be live on entry to the function. MemorySSA represents such
727 /// memory state by the live on entry definition, which is guaranteed to occur
728 /// before any other memory access in the function.
729 inline bool isLiveOnEntryDef(const MemoryAccess *MA) const {
730 return MA == LiveOnEntryDef.get();
731 }
732
733 inline MemoryAccess *getLiveOnEntryDef() const {
734 return LiveOnEntryDef.get();
735 }
736
737 // Sadly, iplists, by default, owns and deletes pointers added to the
738 // list. It's not currently possible to have two iplists for the same type,
739 // where one owns the pointers, and one does not. This is because the traits
740 // are per-type, not per-tag. If this ever changes, we should make the
741 // DefList an iplist.
742 using AccessList = iplist<MemoryAccess, ilist_tag<MSSAHelpers::AllAccessTag>>;
743 using DefsList =
744 simple_ilist<MemoryAccess, ilist_tag<MSSAHelpers::DefsOnlyTag>>;
745
746 /// Return the list of MemoryAccess's for a given basic block.
747 ///
748 /// This list is not modifiable by the user.
749 const AccessList *getBlockAccesses(const BasicBlock *BB) const {
750 return getWritableBlockAccesses(BB);
4
Calling 'MemorySSA::getWritableBlockAccesses'
25
Returning from 'MemorySSA::getWritableBlockAccesses'
26
Returning pointer
751 }
752
753 /// Return the list of MemoryDef's and MemoryPhi's for a given basic
754 /// block.
755 ///
756 /// This list is not modifiable by the user.
757 const DefsList *getBlockDefs(const BasicBlock *BB) const {
758 return getWritableBlockDefs(BB);
759 }
760
761 /// Given two memory accesses in the same basic block, determine
762 /// whether MemoryAccess \p A dominates MemoryAccess \p B.
763 bool locallyDominates(const MemoryAccess *A, const MemoryAccess *B) const;
764
765 /// Given two memory accesses in potentially different blocks,
766 /// determine whether MemoryAccess \p A dominates MemoryAccess \p B.
767 bool dominates(const MemoryAccess *A, const MemoryAccess *B) const;
768
769 /// Given a MemoryAccess and a Use, determine whether MemoryAccess \p A
770 /// dominates Use \p B.
771 bool dominates(const MemoryAccess *A, const Use &B) const;
772
773 /// Verify that MemorySSA is self consistent (IE definitions dominate
774 /// all uses, uses appear in the right places). This is used by unit tests.
775 void verifyMemorySSA() const;
776
777 /// Check clobber sanity for an access.
778 void checkClobberSanityAccess(const MemoryAccess *MA) const;
779
780 /// Used in various insertion functions to specify whether we are talking
781 /// about the beginning or end of a block.
782 enum InsertionPlace { Beginning, End };
783
784protected:
785 // Used by Memory SSA annotater, dumpers, and wrapper pass
786 friend class MemorySSAAnnotatedWriter;
787 friend class MemorySSAPrinterLegacyPass;
788 friend class MemorySSAUpdater;
789
790 void verifyDefUses(Function &F) const;
791 void verifyDomination(Function &F) const;
792 void verifyOrdering(Function &F) const;
793 void verifyDominationNumbers(const Function &F) const;
794 void verifyClobberSanity(const Function &F) const;
795
796 // This is used by the use optimizer and updater.
797 AccessList *getWritableBlockAccesses(const BasicBlock *BB) const {
798 auto It = PerBlockAccesses.find(BB);
799 return It == PerBlockAccesses.end() ? nullptr : It->second.get();
5
Assuming the condition is false
6
'?' condition is false
7
Calling 'unique_ptr::get'
22
Returning from 'unique_ptr::get'
23
Returning pointer
800 }
24
Assigning value
801
802 // This is used by the use optimizer and updater.
803 DefsList *getWritableBlockDefs(const BasicBlock *BB) const {
804 auto It = PerBlockDefs.find(BB);
805 return It == PerBlockDefs.end() ? nullptr : It->second.get();
806 }
807
808 // These is used by the updater to perform various internal MemorySSA
809 // machinsations. They do not always leave the IR in a correct state, and
810 // relies on the updater to fixup what it breaks, so it is not public.
811
812 void moveTo(MemoryUseOrDef *What, BasicBlock *BB, AccessList::iterator Where);
813 void moveTo(MemoryAccess *What, BasicBlock *BB, InsertionPlace Point);
814
815 // Rename the dominator tree branch rooted at BB.
816 void renamePass(BasicBlock *BB, MemoryAccess *IncomingVal,
817 SmallPtrSetImpl<BasicBlock *> &Visited) {
818 renamePass(DT->getNode(BB), IncomingVal, Visited, true, true);
819 }
820
821 void removeFromLookups(MemoryAccess *);
822 void removeFromLists(MemoryAccess *, bool ShouldDelete = true);
823 void insertIntoListsForBlock(MemoryAccess *, const BasicBlock *,
824 InsertionPlace);
825 void insertIntoListsBefore(MemoryAccess *, const BasicBlock *,
826 AccessList::iterator);
827 MemoryUseOrDef *createDefinedAccess(Instruction *, MemoryAccess *,
828 const MemoryUseOrDef *Template = nullptr);
829
830private:
831 class CachingWalker;
832 class OptimizeUses;
833
834 CachingWalker *getWalkerImpl();
835 void buildMemorySSA();
836 void optimizeUses();
837
838 void prepareForMoveTo(MemoryAccess *, BasicBlock *);
839 void verifyUseInDefs(MemoryAccess *, MemoryAccess *) const;
840
841 using AccessMap = DenseMap<const BasicBlock *, std::unique_ptr<AccessList>>;
842 using DefsMap = DenseMap<const BasicBlock *, std::unique_ptr<DefsList>>;
843
844 void
845 determineInsertionPoint(const SmallPtrSetImpl<BasicBlock *> &DefiningBlocks);
846 void markUnreachableAsLiveOnEntry(BasicBlock *BB);
847 bool dominatesUse(const MemoryAccess *, const MemoryAccess *) const;
848 MemoryPhi *createMemoryPhi(BasicBlock *BB);
849 MemoryUseOrDef *createNewAccess(Instruction *,
850 const MemoryUseOrDef *Template = nullptr);
851 MemoryAccess *findDominatingDef(BasicBlock *, enum InsertionPlace);
852 void placePHINodes(const SmallPtrSetImpl<BasicBlock *> &);
853 MemoryAccess *renameBlock(BasicBlock *, MemoryAccess *, bool);
854 void renameSuccessorPhis(BasicBlock *, MemoryAccess *, bool);
855 void renamePass(DomTreeNode *, MemoryAccess *IncomingVal,
856 SmallPtrSetImpl<BasicBlock *> &Visited,
857 bool SkipVisited = false, bool RenameAllUses = false);
858 AccessList *getOrCreateAccessList(const BasicBlock *);
859 DefsList *getOrCreateDefsList(const BasicBlock *);
860 void renumberBlock(const BasicBlock *) const;
861 AliasAnalysis *AA;
862 DominatorTree *DT;
863 Function &F;
864
865 // Memory SSA mappings
866 DenseMap<const Value *, MemoryAccess *> ValueToMemoryAccess;
867
868 // These two mappings contain the main block to access/def mappings for
869 // MemorySSA. The list contained in PerBlockAccesses really owns all the
870 // MemoryAccesses.
871 // Both maps maintain the invariant that if a block is found in them, the
872 // corresponding list is not empty, and if a block is not found in them, the
873 // corresponding list is empty.
874 AccessMap PerBlockAccesses;
875 DefsMap PerBlockDefs;
876 std::unique_ptr<MemoryAccess, ValueDeleter> LiveOnEntryDef;
877
878 // Domination mappings
879 // Note that the numbering is local to a block, even though the map is
880 // global.
881 mutable SmallPtrSet<const BasicBlock *, 16> BlockNumberingValid;
882 mutable DenseMap<const MemoryAccess *, unsigned long> BlockNumbering;
883
884 // Memory SSA building info
885 std::unique_ptr<CachingWalker> Walker;
886 unsigned NextID;
887};
888
889// Internal MemorySSA utils, for use by MemorySSA classes and walkers
890class MemorySSAUtil {
891protected:
892 friend class GVNHoist;
893 friend class MemorySSAWalker;
894
895 // This function should not be used by new passes.
896 static bool defClobbersUseOrDef(MemoryDef *MD, const MemoryUseOrDef *MU,
897 AliasAnalysis &AA);
898};
899
900// This pass does eager building and then printing of MemorySSA. It is used by
901// the tests to be able to build, dump, and verify Memory SSA.
902class MemorySSAPrinterLegacyPass : public FunctionPass {
903public:
904 MemorySSAPrinterLegacyPass();
905
906 bool runOnFunction(Function &) override;
907 void getAnalysisUsage(AnalysisUsage &AU) const override;
908
909 static char ID;
910};
911
912/// An analysis that produces \c MemorySSA for a function.
913///
914class MemorySSAAnalysis : public AnalysisInfoMixin<MemorySSAAnalysis> {
915 friend AnalysisInfoMixin<MemorySSAAnalysis>;
916
917 static AnalysisKey Key;
918
919public:
920 // Wrap MemorySSA result to ensure address stability of internal MemorySSA
921 // pointers after construction. Use a wrapper class instead of plain
922 // unique_ptr<MemorySSA> to avoid build breakage on MSVC.
923 struct Result {
924 Result(std::unique_ptr<MemorySSA> &&MSSA) : MSSA(std::move(MSSA)) {}
925
926 MemorySSA &getMSSA() { return *MSSA.get(); }
927
928 std::unique_ptr<MemorySSA> MSSA;
929 };
930
931 Result run(Function &F, FunctionAnalysisManager &AM);
932};
933
934/// Printer pass for \c MemorySSA.
935class MemorySSAPrinterPass : public PassInfoMixin<MemorySSAPrinterPass> {
936 raw_ostream &OS;
937
938public:
939 explicit MemorySSAPrinterPass(raw_ostream &OS) : OS(OS) {}
940
941 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
942};
943
944/// Verifier pass for \c MemorySSA.
945struct MemorySSAVerifierPass : PassInfoMixin<MemorySSAVerifierPass> {
946 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
947};
948
949/// Legacy analysis pass which computes \c MemorySSA.
950class MemorySSAWrapperPass : public FunctionPass {
951public:
952 MemorySSAWrapperPass();
953
954 static char ID;
955
956 bool runOnFunction(Function &) override;
957 void releaseMemory() override;
958 MemorySSA &getMSSA() { return *MSSA; }
959 const MemorySSA &getMSSA() const { return *MSSA; }
960
961 void getAnalysisUsage(AnalysisUsage &AU) const override;
962
963 void verifyAnalysis() const override;
964 void print(raw_ostream &OS, const Module *M = nullptr) const override;
965
966private:
967 std::unique_ptr<MemorySSA> MSSA;
968};
969
970/// This is the generic walker interface for walkers of MemorySSA.
971/// Walkers are used to be able to further disambiguate the def-use chains
972/// MemorySSA gives you, or otherwise produce better info than MemorySSA gives
973/// you.
974/// In particular, while the def-use chains provide basic information, and are
975/// guaranteed to give, for example, the nearest may-aliasing MemoryDef for a
976/// MemoryUse as AliasAnalysis considers it, a user mant want better or other
977/// information. In particular, they may want to use SCEV info to further
978/// disambiguate memory accesses, or they may want the nearest dominating
979/// may-aliasing MemoryDef for a call or a store. This API enables a
980/// standardized interface to getting and using that info.
981class MemorySSAWalker {
982public:
983 MemorySSAWalker(MemorySSA *);
984 virtual ~MemorySSAWalker() = default;
985
986 using MemoryAccessSet = SmallVector<MemoryAccess *, 8>;
987
988 /// Given a memory Mod/Ref/ModRef'ing instruction, calling this
989 /// will give you the nearest dominating MemoryAccess that Mod's the location
990 /// the instruction accesses (by skipping any def which AA can prove does not
991 /// alias the location(s) accessed by the instruction given).
992 ///
993 /// Note that this will return a single access, and it must dominate the
994 /// Instruction, so if an operand of a MemoryPhi node Mod's the instruction,
995 /// this will return the MemoryPhi, not the operand. This means that
996 /// given:
997 /// if (a) {
998 /// 1 = MemoryDef(liveOnEntry)
999 /// store %a
1000 /// } else {
1001 /// 2 = MemoryDef(liveOnEntry)
1002 /// store %b
1003 /// }
1004 /// 3 = MemoryPhi(2, 1)
1005 /// MemoryUse(3)
1006 /// load %a
1007 ///
1008 /// calling this API on load(%a) will return the MemoryPhi, not the MemoryDef
1009 /// in the if (a) branch.
1010 MemoryAccess *getClobberingMemoryAccess(const Instruction *I) {
1011 MemoryAccess *MA = MSSA->getMemoryAccess(I);
1012 assert(MA && "Handed an instruction that MemorySSA doesn't recognize?")((MA && "Handed an instruction that MemorySSA doesn't recognize?"
) ? static_cast<void> (0) : __assert_fail ("MA && \"Handed an instruction that MemorySSA doesn't recognize?\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1012, __PRETTY_FUNCTION__))
;
1013 return getClobberingMemoryAccess(MA);
1014 }
1015
1016 /// Does the same thing as getClobberingMemoryAccess(const Instruction *I),
1017 /// but takes a MemoryAccess instead of an Instruction.
1018 virtual MemoryAccess *getClobberingMemoryAccess(MemoryAccess *) = 0;
1019
1020 /// Given a potentially clobbering memory access and a new location,
1021 /// calling this will give you the nearest dominating clobbering MemoryAccess
1022 /// (by skipping non-aliasing def links).
1023 ///
1024 /// This version of the function is mainly used to disambiguate phi translated
1025 /// pointers, where the value of a pointer may have changed from the initial
1026 /// memory access. Note that this expects to be handed either a MemoryUse,
1027 /// or an already potentially clobbering access. Unlike the above API, if
1028 /// given a MemoryDef that clobbers the pointer as the starting access, it
1029 /// will return that MemoryDef, whereas the above would return the clobber
1030 /// starting from the use side of the memory def.
1031 virtual MemoryAccess *getClobberingMemoryAccess(MemoryAccess *,
1032 const MemoryLocation &) = 0;
1033
1034 /// Given a memory access, invalidate anything this walker knows about
1035 /// that access.
1036 /// This API is used by walkers that store information to perform basic cache
1037 /// invalidation. This will be called by MemorySSA at appropriate times for
1038 /// the walker it uses or returns.
1039 virtual void invalidateInfo(MemoryAccess *) {}
1040
1041 virtual void verify(const MemorySSA *MSSA) { assert(MSSA == this->MSSA)((MSSA == this->MSSA) ? static_cast<void> (0) : __assert_fail
("MSSA == this->MSSA", "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1041, __PRETTY_FUNCTION__))
; }
1042
1043protected:
1044 friend class MemorySSA; // For updating MSSA pointer in MemorySSA move
1045 // constructor.
1046 MemorySSA *MSSA;
1047};
1048
1049/// A MemorySSAWalker that does no alias queries, or anything else. It
1050/// simply returns the links as they were constructed by the builder.
1051class DoNothingMemorySSAWalker final : public MemorySSAWalker {
1052public:
1053 // Keep the overrides below from hiding the Instruction overload of
1054 // getClobberingMemoryAccess.
1055 using MemorySSAWalker::getClobberingMemoryAccess;
1056
1057 MemoryAccess *getClobberingMemoryAccess(MemoryAccess *) override;
1058 MemoryAccess *getClobberingMemoryAccess(MemoryAccess *,
1059 const MemoryLocation &) override;
1060};
1061
1062using MemoryAccessPair = std::pair<MemoryAccess *, MemoryLocation>;
1063using ConstMemoryAccessPair = std::pair<const MemoryAccess *, MemoryLocation>;
1064
1065/// Iterator base class used to implement const and non-const iterators
1066/// over the defining accesses of a MemoryAccess.
1067template <class T>
1068class memoryaccess_def_iterator_base
1069 : public iterator_facade_base<memoryaccess_def_iterator_base<T>,
1070 std::forward_iterator_tag, T, ptrdiff_t, T *,
1071 T *> {
1072 using BaseT = typename memoryaccess_def_iterator_base::iterator_facade_base;
1073
1074public:
1075 memoryaccess_def_iterator_base(T *Start) : Access(Start) {}
1076 memoryaccess_def_iterator_base() = default;
1077
1078 bool operator==(const memoryaccess_def_iterator_base &Other) const {
1079 return Access == Other.Access && (!Access || ArgNo == Other.ArgNo);
1080 }
1081
1082 // This is a bit ugly, but for MemoryPHI's, unlike PHINodes, you can't get the
1083 // block from the operand in constant time (In a PHINode, the uselist has
1084 // both, so it's just subtraction). We provide it as part of the
1085 // iterator to avoid callers having to linear walk to get the block.
1086 // If the operation becomes constant time on MemoryPHI's, this bit of
1087 // abstraction breaking should be removed.
1088 BasicBlock *getPhiArgBlock() const {
1089 MemoryPhi *MP = dyn_cast<MemoryPhi>(Access);
1090 assert(MP && "Tried to get phi arg block when not iterating over a PHI")((MP && "Tried to get phi arg block when not iterating over a PHI"
) ? static_cast<void> (0) : __assert_fail ("MP && \"Tried to get phi arg block when not iterating over a PHI\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1090, __PRETTY_FUNCTION__))
;
1091 return MP->getIncomingBlock(ArgNo);
1092 }
1093
1094 typename BaseT::iterator::pointer operator*() const {
1095 assert(Access && "Tried to access past the end of our iterator")((Access && "Tried to access past the end of our iterator"
) ? static_cast<void> (0) : __assert_fail ("Access && \"Tried to access past the end of our iterator\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1095, __PRETTY_FUNCTION__))
;
1096 // Go to the first argument for phis, and the defining access for everything
1097 // else.
1098 if (MemoryPhi *MP = dyn_cast<MemoryPhi>(Access))
1099 return MP->getIncomingValue(ArgNo);
1100 return cast<MemoryUseOrDef>(Access)->getDefiningAccess();
1101 }
1102
1103 using BaseT::operator++;
1104 memoryaccess_def_iterator &operator++() {
1105 assert(Access && "Hit end of iterator")((Access && "Hit end of iterator") ? static_cast<void
> (0) : __assert_fail ("Access && \"Hit end of iterator\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1105, __PRETTY_FUNCTION__))
;
1106 if (MemoryPhi *MP = dyn_cast<MemoryPhi>(Access)) {
1107 if (++ArgNo >= MP->getNumIncomingValues()) {
1108 ArgNo = 0;
1109 Access = nullptr;
1110 }
1111 } else {
1112 Access = nullptr;
1113 }
1114 return *this;
1115 }
1116
1117private:
1118 T *Access = nullptr;
1119 unsigned ArgNo = 0;
1120};
1121
1122inline memoryaccess_def_iterator MemoryAccess::defs_begin() {
1123 return memoryaccess_def_iterator(this);
1124}
1125
1126inline const_memoryaccess_def_iterator MemoryAccess::defs_begin() const {
1127 return const_memoryaccess_def_iterator(this);
1128}
1129
1130inline memoryaccess_def_iterator MemoryAccess::defs_end() {
1131 return memoryaccess_def_iterator();
1132}
1133
1134inline const_memoryaccess_def_iterator MemoryAccess::defs_end() const {
1135 return const_memoryaccess_def_iterator();
1136}
1137
1138/// GraphTraits for a MemoryAccess, which walks defs in the normal case,
1139/// and uses in the inverse case.
1140template <> struct GraphTraits<MemoryAccess *> {
1141 using NodeRef = MemoryAccess *;
1142 using ChildIteratorType = memoryaccess_def_iterator;
1143
1144 static NodeRef getEntryNode(NodeRef N) { return N; }
1145 static ChildIteratorType child_begin(NodeRef N) { return N->defs_begin(); }
1146 static ChildIteratorType child_end(NodeRef N) { return N->defs_end(); }
1147};
1148
1149template <> struct GraphTraits<Inverse<MemoryAccess *>> {
1150 using NodeRef = MemoryAccess *;
1151 using ChildIteratorType = MemoryAccess::iterator;
1152
1153 static NodeRef getEntryNode(NodeRef N) { return N; }
1154 static ChildIteratorType child_begin(NodeRef N) { return N->user_begin(); }
1155 static ChildIteratorType child_end(NodeRef N) { return N->user_end(); }
1156};
1157
1158/// Provide an iterator that walks defs, giving both the memory access,
1159/// and the current pointer location, updating the pointer location as it
1160/// changes due to phi node translation.
1161///
1162/// This iterator, while somewhat specialized, is what most clients actually
1163/// want when walking upwards through MemorySSA def chains. It takes a pair of
1164/// <MemoryAccess,MemoryLocation>, and walks defs, properly translating the
1165/// memory location through phi nodes for the user.
1166class upward_defs_iterator
1167 : public iterator_facade_base<upward_defs_iterator,
1168 std::forward_iterator_tag,
1169 const MemoryAccessPair> {
1170 using BaseT = upward_defs_iterator::iterator_facade_base;
1171
1172public:
1173 upward_defs_iterator(const MemoryAccessPair &Info)
1174 : DefIterator(Info.first), Location(Info.second),
1175 OriginalAccess(Info.first) {
1176 CurrentPair.first = nullptr;
1177
1178 WalkingPhi = Info.first && isa<MemoryPhi>(Info.first);
1179 fillInCurrentPair();
1180 }
1181
1182 upward_defs_iterator() { CurrentPair.first = nullptr; }
1183
1184 bool operator==(const upward_defs_iterator &Other) const {
1185 return DefIterator == Other.DefIterator;
1186 }
1187
1188 BaseT::iterator::reference operator*() const {
1189 assert(DefIterator != OriginalAccess->defs_end() &&((DefIterator != OriginalAccess->defs_end() && "Tried to access past the end of our iterator"
) ? static_cast<void> (0) : __assert_fail ("DefIterator != OriginalAccess->defs_end() && \"Tried to access past the end of our iterator\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1190, __PRETTY_FUNCTION__))
1190 "Tried to access past the end of our iterator")((DefIterator != OriginalAccess->defs_end() && "Tried to access past the end of our iterator"
) ? static_cast<void> (0) : __assert_fail ("DefIterator != OriginalAccess->defs_end() && \"Tried to access past the end of our iterator\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1190, __PRETTY_FUNCTION__))
;
1191 return CurrentPair;
1192 }
1193
1194 using BaseT::operator++;
1195 upward_defs_iterator &operator++() {
1196 assert(DefIterator != OriginalAccess->defs_end() &&((DefIterator != OriginalAccess->defs_end() && "Tried to access past the end of the iterator"
) ? static_cast<void> (0) : __assert_fail ("DefIterator != OriginalAccess->defs_end() && \"Tried to access past the end of the iterator\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1197, __PRETTY_FUNCTION__))
1197 "Tried to access past the end of the iterator")((DefIterator != OriginalAccess->defs_end() && "Tried to access past the end of the iterator"
) ? static_cast<void> (0) : __assert_fail ("DefIterator != OriginalAccess->defs_end() && \"Tried to access past the end of the iterator\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1197, __PRETTY_FUNCTION__))
;
1198 ++DefIterator;
1199 if (DefIterator != OriginalAccess->defs_end())
1200 fillInCurrentPair();
1201 return *this;
1202 }
1203
1204 BasicBlock *getPhiArgBlock() const { return DefIterator.getPhiArgBlock(); }
1205
1206private:
1207 void fillInCurrentPair() {
1208 CurrentPair.first = *DefIterator;
1209 if (WalkingPhi && Location.Ptr) {
1210 PHITransAddr Translator(
1211 const_cast<Value *>(Location.Ptr),
1212 OriginalAccess->getBlock()->getModule()->getDataLayout(), nullptr);
1213 if (!Translator.PHITranslateValue(OriginalAccess->getBlock(),
1214 DefIterator.getPhiArgBlock(), nullptr,
1215 false))
1216 if (Translator.getAddr() != Location.Ptr) {
1217 CurrentPair.second = Location.getWithNewPtr(Translator.getAddr());
1218 return;
1219 }
1220 }
1221 CurrentPair.second = Location;
1222 }
1223
1224 MemoryAccessPair CurrentPair;
1225 memoryaccess_def_iterator DefIterator;
1226 MemoryLocation Location;
1227 MemoryAccess *OriginalAccess = nullptr;
1228 bool WalkingPhi = false;
1229};
1230
1231inline upward_defs_iterator upward_defs_begin(const MemoryAccessPair &Pair) {
1232 return upward_defs_iterator(Pair);
1233}
1234
1235inline upward_defs_iterator upward_defs_end() { return upward_defs_iterator(); }
1236
1237inline iterator_range<upward_defs_iterator>
1238upward_defs(const MemoryAccessPair &Pair) {
1239 return make_range(upward_defs_begin(Pair), upward_defs_end());
1240}
1241
1242/// Walks the defining accesses of MemoryDefs. Stops after we hit something that
1243/// has no defining use (e.g. a MemoryPhi or liveOnEntry). Note that, when
1244/// comparing against a null def_chain_iterator, this will compare equal only
1245/// after walking said Phi/liveOnEntry.
1246///
1247/// The UseOptimizedChain flag specifies whether to walk the clobbering
1248/// access chain, or all the accesses.
1249///
1250/// Normally, MemoryDef are all just def/use linked together, so a def_chain on
1251/// a MemoryDef will walk all MemoryDefs above it in the program until it hits
1252/// a phi node. The optimized chain walks the clobbering access of a store.
1253/// So if you are just trying to find, given a store, what the next
1254/// thing that would clobber the same memory is, you want the optimized chain.
1255template <class T, bool UseOptimizedChain = false>
1256struct def_chain_iterator
1257 : public iterator_facade_base<def_chain_iterator<T, UseOptimizedChain>,
1258 std::forward_iterator_tag, MemoryAccess *> {
1259 def_chain_iterator() : MA(nullptr) {}
1260 def_chain_iterator(T MA) : MA(MA) {}
1261
1262 T operator*() const { return MA; }
1263
1264 def_chain_iterator &operator++() {
1265 // N.B. liveOnEntry has a null defining access.
1266 if (auto *MUD = dyn_cast<MemoryUseOrDef>(MA)) {
1267 if (UseOptimizedChain && MUD->isOptimized())
1268 MA = MUD->getOptimized();
1269 else
1270 MA = MUD->getDefiningAccess();
1271 } else {
1272 MA = nullptr;
1273 }
1274
1275 return *this;
1276 }
1277
1278 bool operator==(const def_chain_iterator &O) const { return MA == O.MA; }
1279
1280private:
1281 T MA;
1282};
1283
1284template <class T>
1285inline iterator_range<def_chain_iterator<T>>
1286def_chain(T MA, MemoryAccess *UpTo = nullptr) {
1287#ifdef EXPENSIVE_CHECKS
1288 assert((!UpTo || find(def_chain(MA), UpTo) != def_chain_iterator<T>()) &&(((!UpTo || find(def_chain(MA), UpTo) != def_chain_iterator<
T>()) && "UpTo isn't in the def chain!") ? static_cast
<void> (0) : __assert_fail ("(!UpTo || find(def_chain(MA), UpTo) != def_chain_iterator<T>()) && \"UpTo isn't in the def chain!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1289, __PRETTY_FUNCTION__))
1289 "UpTo isn't in the def chain!")(((!UpTo || find(def_chain(MA), UpTo) != def_chain_iterator<
T>()) && "UpTo isn't in the def chain!") ? static_cast
<void> (0) : __assert_fail ("(!UpTo || find(def_chain(MA), UpTo) != def_chain_iterator<T>()) && \"UpTo isn't in the def chain!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Analysis/MemorySSA.h"
, 1289, __PRETTY_FUNCTION__))
;
1290#endif
1291 return make_range(def_chain_iterator<T>(MA), def_chain_iterator<T>(UpTo));
1292}
1293
1294template <class T>
1295inline iterator_range<def_chain_iterator<T, true>> optimized_def_chain(T MA) {
1296 return make_range(def_chain_iterator<T, true>(MA),
1297 def_chain_iterator<T, true>(nullptr));
1298}
1299
1300} // end namespace llvm
1301
1302#endif // LLVM_ANALYSIS_MEMORYSSA_H

/usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/bits/unique_ptr.h

1// unique_ptr implementation -*- C++ -*-
2
3// Copyright (C) 2008-2016 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file bits/unique_ptr.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{memory}
28 */
29
30#ifndef _UNIQUE_PTR_H1
31#define _UNIQUE_PTR_H1 1
32
33#include <bits/c++config.h>
34#include <debug/assertions.h>
35#include <type_traits>
36#include <utility>
37#include <tuple>
38
39namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
40{
41_GLIBCXX_BEGIN_NAMESPACE_VERSION
42
43 /**
44 * @addtogroup pointer_abstractions
45 * @{
46 */
47
48#if _GLIBCXX_USE_DEPRECATED1
49 template<typename> class auto_ptr;
50#endif
51
52 /// Primary template of default_delete, used by unique_ptr
53 template<typename _Tp>
54 struct default_delete
55 {
56 /// Default constructor
57 constexpr default_delete() noexcept = default;
58
59 /** @brief Converting constructor.
60 *
61 * Allows conversion from a deleter for arrays of another type, @p _Up,
62 * only if @p _Up* is convertible to @p _Tp*.
63 */
64 template<typename _Up, typename = typename
65 enable_if<is_convertible<_Up*, _Tp*>::value>::type>
66 default_delete(const default_delete<_Up>&) noexcept { }
67
68 /// Calls @c delete @p __ptr
69 void
70 operator()(_Tp* __ptr) const
71 {
72 static_assert(!is_void<_Tp>::value,
73 "can't delete pointer to incomplete type");
74 static_assert(sizeof(_Tp)>0,
75 "can't delete pointer to incomplete type");
76 delete __ptr;
77 }
78 };
79
80 // _GLIBCXX_RESOLVE_LIB_DEFECTS
81 // DR 740 - omit specialization for array objects with a compile time length
82 /// Specialization for arrays, default_delete.
83 template<typename _Tp>
84 struct default_delete<_Tp[]>
85 {
86 public:
87 /// Default constructor
88 constexpr default_delete() noexcept = default;
89
90 /** @brief Converting constructor.
91 *
92 * Allows conversion from a deleter for arrays of another type, such as
93 * a const-qualified version of @p _Tp.
94 *
95 * Conversions from types derived from @c _Tp are not allowed because
96 * it is unsafe to @c delete[] an array of derived types through a
97 * pointer to the base type.
98 */
99 template<typename _Up, typename = typename
100 enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type>
101 default_delete(const default_delete<_Up[]>&) noexcept { }
102
103 /// Calls @c delete[] @p __ptr
104 template<typename _Up>
105 typename enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type
106 operator()(_Up* __ptr) const
107 {
108 static_assert(sizeof(_Tp)>0,
109 "can't delete pointer to incomplete type");
110 delete [] __ptr;
111 }
112 };
113
114 /// 20.7.1.2 unique_ptr for single objects.
115 template <typename _Tp, typename _Dp = default_delete<_Tp> >
116 class unique_ptr
117 {
118 // use SFINAE to determine whether _Del::pointer exists
119 class _Pointer
120 {
121 template<typename _Up>
122 static typename _Up::pointer __test(typename _Up::pointer*);
123
124 template<typename _Up>
125 static _Tp* __test(...);
126
127 typedef typename remove_reference<_Dp>::type _Del;
128
129 public:
130 typedef decltype(__test<_Del>(0)) type;
131 };
132
133 typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type;
134 __tuple_type _M_t;
135
136 public:
137 typedef typename _Pointer::type pointer;
138 typedef _Tp element_type;
139 typedef _Dp deleter_type;
140
141
142 // helper template for detecting a safe conversion from another
143 // unique_ptr
144 template<typename _Up, typename _Ep>
145 using __safe_conversion_up = __and_<
146 is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>,
147 __not_<is_array<_Up>>,
148 __or_<__and_<is_reference<deleter_type>,
149 is_same<deleter_type, _Ep>>,
150 __and_<__not_<is_reference<deleter_type>>,
151 is_convertible<_Ep, deleter_type>>
152 >
153 >;
154
155 // Constructors.
156
157 /// Default constructor, creates a unique_ptr that owns nothing.
158 constexpr unique_ptr() noexcept
159 : _M_t()
160 { static_assert(!is_pointer<deleter_type>::value,
161 "constructed with null function pointer deleter"); }
162
163 /** Takes ownership of a pointer.
164 *
165 * @param __p A pointer to an object of @c element_type
166 *
167 * The deleter will be value-initialized.
168 */
169 explicit
170 unique_ptr(pointer __p) noexcept
171 : _M_t()
172 {
173 std::get<0>(_M_t) = __p;
174 static_assert(!is_pointer<deleter_type>::value,
175 "constructed with null function pointer deleter");
176 }
177
178 /** Takes ownership of a pointer.
179 *
180 * @param __p A pointer to an object of @c element_type
181 * @param __d A reference to a deleter.
182 *
183 * The deleter will be initialized with @p __d
184 */
185 unique_ptr(pointer __p,
186 typename conditional<is_reference<deleter_type>::value,
187 deleter_type, const deleter_type&>::type __d) noexcept
188 : _M_t(__p, __d) { }
189
190 /** Takes ownership of a pointer.
191 *
192 * @param __p A pointer to an object of @c element_type
193 * @param __d An rvalue reference to a deleter.
194 *
195 * The deleter will be initialized with @p std::move(__d)
196 */
197 unique_ptr(pointer __p,
198 typename remove_reference<deleter_type>::type&& __d) noexcept
199 : _M_t(std::move(__p), std::move(__d))
200 { static_assert(!std::is_reference<deleter_type>::value,
201 "rvalue deleter bound to reference"); }
202
203 /// Creates a unique_ptr that owns nothing.
204 constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
205
206 // Move constructors.
207
208 /// Move constructor.
209 unique_ptr(unique_ptr&& __u) noexcept
210 : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
211
212 /** @brief Converting constructor from another type
213 *
214 * Requires that the pointer owned by @p __u is convertible to the
215 * type of pointer owned by this object, @p __u does not own an array,
216 * and @p __u has a compatible deleter type.
217 */
218 template<typename _Up, typename _Ep, typename = _Require<
219 __safe_conversion_up<_Up, _Ep>,
220 typename conditional<is_reference<_Dp>::value,
221 is_same<_Ep, _Dp>,
222 is_convertible<_Ep, _Dp>>::type>>
223 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
224 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
225 { }
226
227#if _GLIBCXX_USE_DEPRECATED1
228 /// Converting constructor from @c auto_ptr
229 template<typename _Up, typename = _Require<
230 is_convertible<_Up*, _Tp*>, is_same<_Dp, default_delete<_Tp>>>>
231 unique_ptr(auto_ptr<_Up>&& __u) noexcept;
232#endif
233
234 /// Destructor, invokes the deleter if the stored pointer is not null.
235 ~unique_ptr() noexcept
236 {
237 auto& __ptr = std::get<0>(_M_t);
238 if (__ptr != nullptr)
239 get_deleter()(__ptr);
240 __ptr = pointer();
241 }
242
243 // Assignment.
244
245 /** @brief Move assignment operator.
246 *
247 * @param __u The object to transfer ownership from.
248 *
249 * Invokes the deleter first if this object owns a pointer.
250 */
251 unique_ptr&
252 operator=(unique_ptr&& __u) noexcept
253 {
254 reset(__u.release());
255 get_deleter() = std::forward<deleter_type>(__u.get_deleter());
256 return *this;
257 }
258
259 /** @brief Assignment from another type.
260 *
261 * @param __u The object to transfer ownership from, which owns a
262 * convertible pointer to a non-array object.
263 *
264 * Invokes the deleter first if this object owns a pointer.
265 */
266 template<typename _Up, typename _Ep>
267 typename enable_if< __and_<
268 __safe_conversion_up<_Up, _Ep>,
269 is_assignable<deleter_type&, _Ep&&>
270 >::value,
271 unique_ptr&>::type
272 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
273 {
274 reset(__u.release());
275 get_deleter() = std::forward<_Ep>(__u.get_deleter());
276 return *this;
277 }
278
279 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
280 unique_ptr&
281 operator=(nullptr_t) noexcept
282 {
283 reset();
284 return *this;
285 }
286
287 // Observers.
288
289 /// Dereference the stored pointer.
290 typename add_lvalue_reference<element_type>::type
291 operator*() const
292 {
293 __glibcxx_assert(get() != pointer());
294 return *get();
295 }
296
297 /// Return the stored pointer.
298 pointer
299 operator->() const noexcept
300 {
301 _GLIBCXX_DEBUG_PEDASSERT(get() != pointer());
302 return get();
303 }
304
305 /// Return the stored pointer.
306 pointer
307 get() const noexcept
308 { return std::get<0>(_M_t); }
8
Calling 'get<0, llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > *, std::default_delete<llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > >>'
19
Returning from 'get<0, llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > *, std::default_delete<llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > >>'
20
Returning pointer
21
Assigning value
309
310 /// Return a reference to the stored deleter.
311 deleter_type&
312 get_deleter() noexcept
313 { return std::get<1>(_M_t); }
314
315 /// Return a reference to the stored deleter.
316 const deleter_type&
317 get_deleter() const noexcept
318 { return std::get<1>(_M_t); }
319
320 /// Return @c true if the stored pointer is not null.
321 explicit operator bool() const noexcept
322 { return get() == pointer() ? false : true; }
323
324 // Modifiers.
325
326 /// Release ownership of any stored pointer.
327 pointer
328 release() noexcept
329 {
330 pointer __p = get();
331 std::get<0>(_M_t) = pointer();
332 return __p;
333 }
334
335 /** @brief Replace the stored pointer.
336 *
337 * @param __p The new pointer to store.
338 *
339 * The deleter will be invoked if a pointer is already owned.
340 */
341 void
342 reset(pointer __p = pointer()) noexcept
343 {
344 using std::swap;
345 swap(std::get<0>(_M_t), __p);
346 if (__p != pointer())
347 get_deleter()(__p);
348 }
349
350 /// Exchange the pointer and deleter with another object.
351 void
352 swap(unique_ptr& __u) noexcept
353 {
354 using std::swap;
355 swap(_M_t, __u._M_t);
356 }
357
358 // Disable copy from lvalue.
359 unique_ptr(const unique_ptr&) = delete;
360 unique_ptr& operator=(const unique_ptr&) = delete;
361 };
362
363 /// 20.7.1.3 unique_ptr for array objects with a runtime length
364 // [unique.ptr.runtime]
365 // _GLIBCXX_RESOLVE_LIB_DEFECTS
366 // DR 740 - omit specialization for array objects with a compile time length
367 template<typename _Tp, typename _Dp>
368 class unique_ptr<_Tp[], _Dp>
369 {
370 // use SFINAE to determine whether _Del::pointer exists
371 class _Pointer
372 {
373 template<typename _Up>
374 static typename _Up::pointer __test(typename _Up::pointer*);
375
376 template<typename _Up>
377 static _Tp* __test(...);
378
379 typedef typename remove_reference<_Dp>::type _Del;
380
381 public:
382 typedef decltype(__test<_Del>(0)) type;
383 };
384
385 typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type;
386 __tuple_type _M_t;
387
388 template<typename _Up>
389 using __remove_cv = typename remove_cv<_Up>::type;
390
391 // like is_base_of<_Tp, _Up> but false if unqualified types are the same
392 template<typename _Up>
393 using __is_derived_Tp
394 = __and_< is_base_of<_Tp, _Up>,
395 __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >;
396
397
398 public:
399 typedef typename _Pointer::type pointer;
400 typedef _Tp element_type;
401 typedef _Dp deleter_type;
402
403 // helper template for detecting a safe conversion from another
404 // unique_ptr
405 template<typename _Up, typename _Ep,
406 typename _Up_up = unique_ptr<_Up, _Ep>,
407 typename _Up_element_type = typename _Up_up::element_type>
408 using __safe_conversion_up = __and_<
409 is_array<_Up>,
410 is_same<pointer, element_type*>,
411 is_same<typename _Up_up::pointer, _Up_element_type*>,
412 is_convertible<_Up_element_type(*)[], element_type(*)[]>,
413 __or_<__and_<is_reference<deleter_type>, is_same<deleter_type, _Ep>>,
414 __and_<__not_<is_reference<deleter_type>>,
415 is_convertible<_Ep, deleter_type>>>
416 >;
417
418 // helper template for detecting a safe conversion from a raw pointer
419 template<typename _Up>
420 using __safe_conversion_raw = __and_<
421 __or_<__or_<is_same<_Up, pointer>,
422 is_same<_Up, nullptr_t>>,
423 __and_<is_pointer<_Up>,
424 is_same<pointer, element_type*>,
425 is_convertible<
426 typename remove_pointer<_Up>::type(*)[],
427 element_type(*)[]>
428 >
429 >
430 >;
431
432 // Constructors.
433
434 /// Default constructor, creates a unique_ptr that owns nothing.
435 constexpr unique_ptr() noexcept
436 : _M_t()
437 { static_assert(!std::is_pointer<deleter_type>::value,
438 "constructed with null function pointer deleter"); }
439
440 /** Takes ownership of a pointer.
441 *
442 * @param __p A pointer to an array of a type safely convertible
443 * to an array of @c element_type
444 *
445 * The deleter will be value-initialized.
446 */
447 template<typename _Up,
448 typename = typename enable_if<
449 __safe_conversion_raw<_Up>::value, bool>::type>
450 explicit
451 unique_ptr(_Up __p) noexcept
452 : _M_t(__p, deleter_type())
453 { static_assert(!is_pointer<deleter_type>::value,
454 "constructed with null function pointer deleter"); }
455
456 /** Takes ownership of a pointer.
457 *
458 * @param __p A pointer to an array of a type safely convertible
459 * to an array of @c element_type
460 * @param __d A reference to a deleter.
461 *
462 * The deleter will be initialized with @p __d
463 */
464 template<typename _Up,
465 typename = typename enable_if<
466 __safe_conversion_raw<_Up>::value, bool>::type>
467 unique_ptr(_Up __p,
468 typename conditional<is_reference<deleter_type>::value,
469 deleter_type, const deleter_type&>::type __d) noexcept
470 : _M_t(__p, __d) { }
471
472 /** Takes ownership of a pointer.
473 *
474 * @param __p A pointer to an array of a type safely convertible
475 * to an array of @c element_type
476 * @param __d A reference to a deleter.
477 *
478 * The deleter will be initialized with @p std::move(__d)
479 */
480 template<typename _Up,
481 typename = typename enable_if<
482 __safe_conversion_raw<_Up>::value, bool>::type>
483 unique_ptr(_Up __p, typename
484 remove_reference<deleter_type>::type&& __d) noexcept
485 : _M_t(std::move(__p), std::move(__d))
486 { static_assert(!is_reference<deleter_type>::value,
487 "rvalue deleter bound to reference"); }
488
489 /// Move constructor.
490 unique_ptr(unique_ptr&& __u) noexcept
491 : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
492
493 /// Creates a unique_ptr that owns nothing.
494 constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
495
496 template<typename _Up, typename _Ep,
497 typename = _Require<__safe_conversion_up<_Up, _Ep>>>
498 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
499 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
500 { }
501
502 /// Destructor, invokes the deleter if the stored pointer is not null.
503 ~unique_ptr()
504 {
505 auto& __ptr = std::get<0>(_M_t);
506 if (__ptr != nullptr)
507 get_deleter()(__ptr);
508 __ptr = pointer();
509 }
510
511 // Assignment.
512
513 /** @brief Move assignment operator.
514 *
515 * @param __u The object to transfer ownership from.
516 *
517 * Invokes the deleter first if this object owns a pointer.
518 */
519 unique_ptr&
520 operator=(unique_ptr&& __u) noexcept
521 {
522 reset(__u.release());
523 get_deleter() = std::forward<deleter_type>(__u.get_deleter());
524 return *this;
525 }
526
527 /** @brief Assignment from another type.
528 *
529 * @param __u The object to transfer ownership from, which owns a
530 * convertible pointer to an array object.
531 *
532 * Invokes the deleter first if this object owns a pointer.
533 */
534 template<typename _Up, typename _Ep>
535 typename
536 enable_if<__and_<__safe_conversion_up<_Up, _Ep>,
537 is_assignable<deleter_type&, _Ep&&>
538 >::value,
539 unique_ptr&>::type
540 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
541 {
542 reset(__u.release());
543 get_deleter() = std::forward<_Ep>(__u.get_deleter());
544 return *this;
545 }
546
547 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
548 unique_ptr&
549 operator=(nullptr_t) noexcept
550 {
551 reset();
552 return *this;
553 }
554
555 // Observers.
556
557 /// Access an element of owned array.
558 typename std::add_lvalue_reference<element_type>::type
559 operator[](size_t __i) const
560 {
561 __glibcxx_assert(get() != pointer());
562 return get()[__i];
563 }
564
565 /// Return the stored pointer.
566 pointer
567 get() const noexcept
568 { return std::get<0>(_M_t); }
569
570 /// Return a reference to the stored deleter.
571 deleter_type&
572 get_deleter() noexcept
573 { return std::get<1>(_M_t); }
574
575 /// Return a reference to the stored deleter.
576 const deleter_type&
577 get_deleter() const noexcept
578 { return std::get<1>(_M_t); }
579
580 /// Return @c true if the stored pointer is not null.
581 explicit operator bool() const noexcept
582 { return get() == pointer() ? false : true; }
583
584 // Modifiers.
585
586 /// Release ownership of any stored pointer.
587 pointer
588 release() noexcept
589 {
590 pointer __p = get();
591 std::get<0>(_M_t) = pointer();
592 return __p;
593 }
594
595 /** @brief Replace the stored pointer.
596 *
597 * @param __p The new pointer to store.
598 *
599 * The deleter will be invoked if a pointer is already owned.
600 */
601 template <typename _Up,
602 typename = _Require<
603 __or_<is_same<_Up, pointer>,
604 __and_<is_same<pointer, element_type*>,
605 is_pointer<_Up>,
606 is_convertible<
607 typename remove_pointer<_Up>::type(*)[],
608 element_type(*)[]
609 >
610 >
611 >
612 >>
613 void
614 reset(_Up __p) noexcept
615 {
616 pointer __ptr = __p;
617 using std::swap;
618 swap(std::get<0>(_M_t), __ptr);
619 if (__ptr != nullptr)
620 get_deleter()(__ptr);
621 }
622
623 void reset(nullptr_t = nullptr) noexcept
624 {
625 reset(pointer());
626 }
627
628 /// Exchange the pointer and deleter with another object.
629 void
630 swap(unique_ptr& __u) noexcept
631 {
632 using std::swap;
633 swap(_M_t, __u._M_t);
634 }
635
636 // Disable copy from lvalue.
637 unique_ptr(const unique_ptr&) = delete;
638 unique_ptr& operator=(const unique_ptr&) = delete;
639 };
640
641 template<typename _Tp, typename _Dp>
642 inline void
643 swap(unique_ptr<_Tp, _Dp>& __x,
644 unique_ptr<_Tp, _Dp>& __y) noexcept
645 { __x.swap(__y); }
646
647 template<typename _Tp, typename _Dp,
648 typename _Up, typename _Ep>
649 inline bool
650 operator==(const unique_ptr<_Tp, _Dp>& __x,
651 const unique_ptr<_Up, _Ep>& __y)
652 { return __x.get() == __y.get(); }
653
654 template<typename _Tp, typename _Dp>
655 inline bool
656 operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
657 { return !__x; }
658
659 template<typename _Tp, typename _Dp>
660 inline bool
661 operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
662 { return !__x; }
663
664 template<typename _Tp, typename _Dp,
665 typename _Up, typename _Ep>
666 inline bool
667 operator!=(const unique_ptr<_Tp, _Dp>& __x,
668 const unique_ptr<_Up, _Ep>& __y)
669 { return __x.get() != __y.get(); }
670
671 template<typename _Tp, typename _Dp>
672 inline bool
673 operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
674 { return (bool)__x; }
675
676 template<typename _Tp, typename _Dp>
677 inline bool
678 operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
679 { return (bool)__x; }
680
681 template<typename _Tp, typename _Dp,
682 typename _Up, typename _Ep>
683 inline bool
684 operator<(const unique_ptr<_Tp, _Dp>& __x,
685 const unique_ptr<_Up, _Ep>& __y)
686 {
687 typedef typename
688 std::common_type<typename unique_ptr<_Tp, _Dp>::pointer,
689 typename unique_ptr<_Up, _Ep>::pointer>::type _CT;
690 return std::less<_CT>()(__x.get(), __y.get());
691 }
692
693 template<typename _Tp, typename _Dp>
694 inline bool
695 operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
696 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
697 nullptr); }
698
699 template<typename _Tp, typename _Dp>
700 inline bool
701 operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
702 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
703 __x.get()); }
704
705 template<typename _Tp, typename _Dp,
706 typename _Up, typename _Ep>
707 inline bool
708 operator<=(const unique_ptr<_Tp, _Dp>& __x,
709 const unique_ptr<_Up, _Ep>& __y)
710 { return !(__y < __x); }
711
712 template<typename _Tp, typename _Dp>
713 inline bool
714 operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
715 { return !(nullptr < __x); }
716
717 template<typename _Tp, typename _Dp>
718 inline bool
719 operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
720 { return !(__x < nullptr); }
721
722 template<typename _Tp, typename _Dp,
723 typename _Up, typename _Ep>
724 inline bool
725 operator>(const unique_ptr<_Tp, _Dp>& __x,
726 const unique_ptr<_Up, _Ep>& __y)
727 { return (__y < __x); }
728
729 template<typename _Tp, typename _Dp>
730 inline bool
731 operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
732 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
733 __x.get()); }
734
735 template<typename _Tp, typename _Dp>
736 inline bool
737 operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
738 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
739 nullptr); }
740
741 template<typename _Tp, typename _Dp,
742 typename _Up, typename _Ep>
743 inline bool
744 operator>=(const unique_ptr<_Tp, _Dp>& __x,
745 const unique_ptr<_Up, _Ep>& __y)
746 { return !(__x < __y); }
747
748 template<typename _Tp, typename _Dp>
749 inline bool
750 operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
751 { return !(__x < nullptr); }
752
753 template<typename _Tp, typename _Dp>
754 inline bool
755 operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
756 { return !(nullptr < __x); }
757
758 /// std::hash specialization for unique_ptr.
759 template<typename _Tp, typename _Dp>
760 struct hash<unique_ptr<_Tp, _Dp>>
761 : public __hash_base<size_t, unique_ptr<_Tp, _Dp>>
762 {
763 size_t
764 operator()(const unique_ptr<_Tp, _Dp>& __u) const noexcept
765 {
766 typedef unique_ptr<_Tp, _Dp> _UP;
767 return std::hash<typename _UP::pointer>()(__u.get());
768 }
769 };
770
771#if __cplusplus201103L > 201103L
772
773#define __cpp_lib_make_unique 201304
774
775 template<typename _Tp>
776 struct _MakeUniq
777 { typedef unique_ptr<_Tp> __single_object; };
778
779 template<typename _Tp>
780 struct _MakeUniq<_Tp[]>
781 { typedef unique_ptr<_Tp[]> __array; };
782
783 template<typename _Tp, size_t _Bound>
784 struct _MakeUniq<_Tp[_Bound]>
785 { struct __invalid_type { }; };
786
787 /// std::make_unique for single objects
788 template<typename _Tp, typename... _Args>
789 inline typename _MakeUniq<_Tp>::__single_object
790 make_unique(_Args&&... __args)
791 { return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...)); }
792
793 /// std::make_unique for arrays of unknown bound
794 template<typename _Tp>
795 inline typename _MakeUniq<_Tp>::__array
796 make_unique(size_t __num)
797 { return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]()); }
798
799 /// Disable std::make_unique for arrays of known bound
800 template<typename _Tp, typename... _Args>
801 inline typename _MakeUniq<_Tp>::__invalid_type
802 make_unique(_Args&&...) = delete;
803#endif
804
805 // @} group pointer_abstractions
806
807_GLIBCXX_END_NAMESPACE_VERSION
808} // namespace
809
810#endif /* _UNIQUE_PTR_H */

/usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/tuple

1// <tuple> -*- C++ -*-
2
3// Copyright (C) 2007-2016 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file include/tuple
26 * This is a Standard C++ Library header.
27 */
28
29#ifndef _GLIBCXX_TUPLE1
30#define _GLIBCXX_TUPLE1 1
31
32#pragma GCC system_header
33
34#if __cplusplus201103L < 201103L
35# include <bits/c++0x_warning.h>
36#else
37
38#include <utility>
39#include <array>
40#include <bits/uses_allocator.h>
41
42namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
43{
44_GLIBCXX_BEGIN_NAMESPACE_VERSION
45
46 /**
47 * @addtogroup utilities
48 * @{
49 */
50
51 template<std::size_t _Idx, typename _Head, bool _IsEmptyNotFinal>
52 struct _Head_base;
53
54 template<std::size_t _Idx, typename _Head>
55 struct _Head_base<_Idx, _Head, true>
56 : public _Head
57 {
58 constexpr _Head_base()
59 : _Head() { }
60
61 constexpr _Head_base(const _Head& __h)
62 : _Head(__h) { }
63
64 constexpr _Head_base(const _Head_base&) = default;
65 constexpr _Head_base(_Head_base&&) = default;
66
67 template<typename _UHead>
68 constexpr _Head_base(_UHead&& __h)
69 : _Head(std::forward<_UHead>(__h)) { }
70
71 _Head_base(allocator_arg_t, __uses_alloc0)
72 : _Head() { }
73
74 template<typename _Alloc>
75 _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a)
76 : _Head(allocator_arg, *__a._M_a) { }
77
78 template<typename _Alloc>
79 _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a)
80 : _Head(*__a._M_a) { }
81
82 template<typename _UHead>
83 _Head_base(__uses_alloc0, _UHead&& __uhead)
84 : _Head(std::forward<_UHead>(__uhead)) { }
85
86 template<typename _Alloc, typename _UHead>
87 _Head_base(__uses_alloc1<_Alloc> __a, _UHead&& __uhead)
88 : _Head(allocator_arg, *__a._M_a, std::forward<_UHead>(__uhead)) { }
89
90 template<typename _Alloc, typename _UHead>
91 _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
92 : _Head(std::forward<_UHead>(__uhead), *__a._M_a) { }
93
94 static constexpr _Head&
95 _M_head(_Head_base& __b) noexcept { return __b; }
96
97 static constexpr const _Head&
98 _M_head(const _Head_base& __b) noexcept { return __b; }
99 };
100
101 template<std::size_t _Idx, typename _Head>
102 struct _Head_base<_Idx, _Head, false>
103 {
104 constexpr _Head_base()
105 : _M_head_impl() { }
106
107 constexpr _Head_base(const _Head& __h)
108 : _M_head_impl(__h) { }
109
110 constexpr _Head_base(const _Head_base&) = default;
111 constexpr _Head_base(_Head_base&&) = default;
112
113 template<typename _UHead>
114 constexpr _Head_base(_UHead&& __h)
115 : _M_head_impl(std::forward<_UHead>(__h)) { }
116
117 _Head_base(allocator_arg_t, __uses_alloc0)
118 : _M_head_impl() { }
119
120 template<typename _Alloc>
121 _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a)
122 : _M_head_impl(allocator_arg, *__a._M_a) { }
123
124 template<typename _Alloc>
125 _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a)
126 : _M_head_impl(*__a._M_a) { }
127
128 template<typename _UHead>
129 _Head_base(__uses_alloc0, _UHead&& __uhead)
130 : _M_head_impl(std::forward<_UHead>(__uhead)) { }
131
132 template<typename _Alloc, typename _UHead>
133 _Head_base(__uses_alloc1<_Alloc> __a, _UHead&& __uhead)
134 : _M_head_impl(allocator_arg, *__a._M_a, std::forward<_UHead>(__uhead))
135 { }
136
137 template<typename _Alloc, typename _UHead>
138 _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
139 : _M_head_impl(std::forward<_UHead>(__uhead), *__a._M_a) { }
140
141 static constexpr _Head&
142 _M_head(_Head_base& __b) noexcept { return __b._M_head_impl; }
143
144 static constexpr const _Head&
145 _M_head(const _Head_base& __b) noexcept { return __b._M_head_impl; }
12
Returning pointer (reference to field '_M_head_impl')
146
147 _Head _M_head_impl;
148 };
149
150 /**
151 * Contains the actual implementation of the @c tuple template, stored
152 * as a recursive inheritance hierarchy from the first element (most
153 * derived class) to the last (least derived class). The @c Idx
154 * parameter gives the 0-based index of the element stored at this
155 * point in the hierarchy; we use it to implement a constant-time
156 * get() operation.
157 */
158 template<std::size_t _Idx, typename... _Elements>
159 struct _Tuple_impl;
160
161 template<typename _Tp>
162 struct __is_empty_non_tuple : is_empty<_Tp> { };
163
164 // Using EBO for elements that are tuples causes ambiguous base errors.
165 template<typename _El0, typename... _El>
166 struct __is_empty_non_tuple<tuple<_El0, _El...>> : false_type { };
167
168 // Use the Empty Base-class Optimization for empty, non-final types.
169 template<typename _Tp>
170 using __empty_not_final
171 = typename conditional<__is_final(_Tp), false_type,
172 __is_empty_non_tuple<_Tp>>::type;
173
174 /**
175 * Recursive tuple implementation. Here we store the @c Head element
176 * and derive from a @c Tuple_impl containing the remaining elements
177 * (which contains the @c Tail).
178 */
179 template<std::size_t _Idx, typename _Head, typename... _Tail>
180 struct _Tuple_impl<_Idx, _Head, _Tail...>
181 : public _Tuple_impl<_Idx + 1, _Tail...>,
182 private _Head_base<_Idx, _Head, __empty_not_final<_Head>::value>
183 {
184 template<std::size_t, typename...> friend class _Tuple_impl;
185
186 typedef _Tuple_impl<_Idx + 1, _Tail...> _Inherited;
187 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
188
189 static constexpr _Head&
190 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
191
192 static constexpr const _Head&
193 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
11
Calling '_Head_base::_M_head'
13
Returning from '_Head_base::_M_head'
14
Returning pointer (reference to field '_M_head_impl')
194
195 static constexpr _Inherited&
196 _M_tail(_Tuple_impl& __t) noexcept { return __t; }
197
198 static constexpr const _Inherited&
199 _M_tail(const _Tuple_impl& __t) noexcept { return __t; }
200
201 constexpr _Tuple_impl()
202 : _Inherited(), _Base() { }
203
204 explicit
205 constexpr _Tuple_impl(const _Head& __head, const _Tail&... __tail)
206 : _Inherited(__tail...), _Base(__head) { }
207
208 template<typename _UHead, typename... _UTail, typename = typename
209 enable_if<sizeof...(_Tail) == sizeof...(_UTail)>::type>
210 explicit
211 constexpr _Tuple_impl(_UHead&& __head, _UTail&&... __tail)
212 : _Inherited(std::forward<_UTail>(__tail)...),
213 _Base(std::forward<_UHead>(__head)) { }
214
215 constexpr _Tuple_impl(const _Tuple_impl&) = default;
216
217 constexpr
218 _Tuple_impl(_Tuple_impl&& __in)
219 noexcept(__and_<is_nothrow_move_constructible<_Head>,
220 is_nothrow_move_constructible<_Inherited>>::value)
221 : _Inherited(std::move(_M_tail(__in))),
222 _Base(std::forward<_Head>(_M_head(__in))) { }
223
224 template<typename... _UElements>
225 constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UElements...>& __in)
226 : _Inherited(_Tuple_impl<_Idx, _UElements...>::_M_tail(__in)),
227 _Base(_Tuple_impl<_Idx, _UElements...>::_M_head(__in)) { }
228
229 template<typename _UHead, typename... _UTails>
230 constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
231 : _Inherited(std::move
232 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in))),
233 _Base(std::forward<_UHead>
234 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
235
236 template<typename _Alloc>
237 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a)
238 : _Inherited(__tag, __a),
239 _Base(__tag, __use_alloc<_Head>(__a)) { }
240
241 template<typename _Alloc>
242 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
243 const _Head& __head, const _Tail&... __tail)
244 : _Inherited(__tag, __a, __tail...),
245 _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { }
246
247 template<typename _Alloc, typename _UHead, typename... _UTail,
248 typename = typename enable_if<sizeof...(_Tail)
249 == sizeof...(_UTail)>::type>
250 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
251 _UHead&& __head, _UTail&&... __tail)
252 : _Inherited(__tag, __a, std::forward<_UTail>(__tail)...),
253 _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
254 std::forward<_UHead>(__head)) { }
255
256 template<typename _Alloc>
257 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
258 const _Tuple_impl& __in)
259 : _Inherited(__tag, __a, _M_tail(__in)),
260 _Base(__use_alloc<_Head, _Alloc, _Head>(__a), _M_head(__in)) { }
261
262 template<typename _Alloc>
263 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
264 _Tuple_impl&& __in)
265 : _Inherited(__tag, __a, std::move(_M_tail(__in))),
266 _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
267 std::forward<_Head>(_M_head(__in))) { }
268
269 template<typename _Alloc, typename... _UElements>
270 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
271 const _Tuple_impl<_Idx, _UElements...>& __in)
272 : _Inherited(__tag, __a,
273 _Tuple_impl<_Idx, _UElements...>::_M_tail(__in)),
274 _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
275 _Tuple_impl<_Idx, _UElements...>::_M_head(__in)) { }
276
277 template<typename _Alloc, typename _UHead, typename... _UTails>
278 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
279 _Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
280 : _Inherited(__tag, __a, std::move
281 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in))),
282 _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
283 std::forward<_UHead>
284 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
285
286 _Tuple_impl&
287 operator=(const _Tuple_impl& __in)
288 {
289 _M_head(*this) = _M_head(__in);
290 _M_tail(*this) = _M_tail(__in);
291 return *this;
292 }
293
294 _Tuple_impl&
295 operator=(_Tuple_impl&& __in)
296 noexcept(__and_<is_nothrow_move_assignable<_Head>,
297 is_nothrow_move_assignable<_Inherited>>::value)
298 {
299 _M_head(*this) = std::forward<_Head>(_M_head(__in));
300 _M_tail(*this) = std::move(_M_tail(__in));
301 return *this;
302 }
303
304 template<typename... _UElements>
305 _Tuple_impl&
306 operator=(const _Tuple_impl<_Idx, _UElements...>& __in)
307 {
308 _M_head(*this) = _Tuple_impl<_Idx, _UElements...>::_M_head(__in);
309 _M_tail(*this) = _Tuple_impl<_Idx, _UElements...>::_M_tail(__in);
310 return *this;
311 }
312
313 template<typename _UHead, typename... _UTails>
314 _Tuple_impl&
315 operator=(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
316 {
317 _M_head(*this) = std::forward<_UHead>
318 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in));
319 _M_tail(*this) = std::move
320 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in));
321 return *this;
322 }
323
324 protected:
325 void
326 _M_swap(_Tuple_impl& __in)
327 noexcept(__is_nothrow_swappable<_Head>::value
328 && noexcept(_M_tail(__in)._M_swap(_M_tail(__in))))
329 {
330 using std::swap;
331 swap(_M_head(*this), _M_head(__in));
332 _Inherited::_M_swap(_M_tail(__in));
333 }
334 };
335
336 // Basis case of inheritance recursion.
337 template<std::size_t _Idx, typename _Head>
338 struct _Tuple_impl<_Idx, _Head>
339 : private _Head_base<_Idx, _Head, __empty_not_final<_Head>::value>
340 {
341 template<std::size_t, typename...> friend class _Tuple_impl;
342
343 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
344
345 static constexpr _Head&
346 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
347
348 static constexpr const _Head&
349 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
350
351 constexpr _Tuple_impl()
352 : _Base() { }
353
354 explicit
355 constexpr _Tuple_impl(const _Head& __head)
356 : _Base(__head) { }
357
358 template<typename _UHead>
359 explicit
360 constexpr _Tuple_impl(_UHead&& __head)
361 : _Base(std::forward<_UHead>(__head)) { }
362
363 constexpr _Tuple_impl(const _Tuple_impl&) = default;
364
365 constexpr
366 _Tuple_impl(_Tuple_impl&& __in)
367 noexcept(is_nothrow_move_constructible<_Head>::value)
368 : _Base(std::forward<_Head>(_M_head(__in))) { }
369
370 template<typename _UHead>
371 constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UHead>& __in)
372 : _Base(_Tuple_impl<_Idx, _UHead>::_M_head(__in)) { }
373
374 template<typename _UHead>
375 constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead>&& __in)
376 : _Base(std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
377 { }
378
379 template<typename _Alloc>
380 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a)
381 : _Base(__tag, __use_alloc<_Head>(__a)) { }
382
383 template<typename _Alloc>
384 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
385 const _Head& __head)
386 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { }
387
388 template<typename _Alloc, typename _UHead>
389 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
390 _UHead&& __head)
391 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
392 std::forward<_UHead>(__head)) { }
393
394 template<typename _Alloc>
395 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
396 const _Tuple_impl& __in)
397 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), _M_head(__in)) { }
398
399 template<typename _Alloc>
400 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
401 _Tuple_impl&& __in)
402 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
403 std::forward<_Head>(_M_head(__in))) { }
404
405 template<typename _Alloc, typename _UHead>
406 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
407 const _Tuple_impl<_Idx, _UHead>& __in)
408 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
409 _Tuple_impl<_Idx, _UHead>::_M_head(__in)) { }
410
411 template<typename _Alloc, typename _UHead>
412 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
413 _Tuple_impl<_Idx, _UHead>&& __in)
414 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
415 std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
416 { }
417
418 _Tuple_impl&
419 operator=(const _Tuple_impl& __in)
420 {
421 _M_head(*this) = _M_head(__in);
422 return *this;
423 }
424
425 _Tuple_impl&
426 operator=(_Tuple_impl&& __in)
427 noexcept(is_nothrow_move_assignable<_Head>::value)
428 {
429 _M_head(*this) = std::forward<_Head>(_M_head(__in));
430 return *this;
431 }
432
433 template<typename _UHead>
434 _Tuple_impl&
435 operator=(const _Tuple_impl<_Idx, _UHead>& __in)
436 {
437 _M_head(*this) = _Tuple_impl<_Idx, _UHead>::_M_head(__in);
438 return *this;
439 }
440
441 template<typename _UHead>
442 _Tuple_impl&
443 operator=(_Tuple_impl<_Idx, _UHead>&& __in)
444 {
445 _M_head(*this)
446 = std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in));
447 return *this;
448 }
449
450 protected:
451 void
452 _M_swap(_Tuple_impl& __in)
453 noexcept(__is_nothrow_swappable<_Head>::value)
454 {
455 using std::swap;
456 swap(_M_head(*this), _M_head(__in));
457 }
458 };
459
460 template<typename... _Elements>
461 class tuple;
462
463 // Concept utility functions, reused in conditionally-explicit
464 // constructors.
465 template<bool, typename... _Elements>
466 struct _TC
467 {
468 template<typename... _UElements>
469 static constexpr bool _ConstructibleTuple()
470 {
471 return __and_<is_constructible<_Elements, const _UElements&>...>::value;
472 }
473
474 template<typename... _UElements>
475 static constexpr bool _ImplicitlyConvertibleTuple()
476 {
477 return __and_<is_convertible<const _UElements&, _Elements>...>::value;
478 }
479
480 template<typename... _UElements>
481 static constexpr bool _MoveConstructibleTuple()
482 {
483 return __and_<is_constructible<_Elements, _UElements&&>...>::value;
484 }
485
486 template<typename... _UElements>
487 static constexpr bool _ImplicitlyMoveConvertibleTuple()
488 {
489 return __and_<is_convertible<_UElements&&, _Elements>...>::value;
490 }
491
492 template<typename _SrcTuple>
493 static constexpr bool _NonNestedTuple()
494 {
495 return __and_<__not_<is_same<tuple<_Elements...>,
496 typename remove_cv<
497 typename remove_reference<_SrcTuple>::type
498 >::type>>,
499 __not_<is_convertible<_SrcTuple, _Elements...>>,
500 __not_<is_constructible<_Elements..., _SrcTuple>>
501 >::value;
502 }
503 template<typename... _UElements>
504 static constexpr bool _NotSameTuple()
505 {
506 return __not_<is_same<tuple<_Elements...>,
507 typename remove_const<
508 typename remove_reference<_UElements...>::type
509 >::type>>::value;
510 }
511 };
512
513 template<typename... _Elements>
514 struct _TC<false, _Elements...>
515 {
516 template<typename... _UElements>
517 static constexpr bool _ConstructibleTuple()
518 {
519 return false;
520 }
521
522 template<typename... _UElements>
523 static constexpr bool _ImplicitlyConvertibleTuple()
524 {
525 return false;
526 }
527
528 template<typename... _UElements>
529 static constexpr bool _MoveConstructibleTuple()
530 {
531 return false;
532 }
533
534 template<typename... _UElements>
535 static constexpr bool _ImplicitlyMoveConvertibleTuple()
536 {
537 return false;
538 }
539
540 template<typename... _UElements>
541 static constexpr bool _NonNestedTuple()
542 {
543 return true;
544 }
545 template<typename... _UElements>
546 static constexpr bool _NotSameTuple()
547 {
548 return true;
549 }
550 };
551
552 /// Primary class template, tuple
553 template<typename... _Elements>
554 class tuple : public _Tuple_impl<0, _Elements...>
555 {
556 typedef _Tuple_impl<0, _Elements...> _Inherited;
557
558 // Used for constraining the default constructor so
559 // that it becomes dependent on the constraints.
560 template<typename _Dummy>
561 struct _TC2
562 {
563 static constexpr bool _DefaultConstructibleTuple()
564 {
565 return __and_<is_default_constructible<_Elements>...>::value;
566 }
567 static constexpr bool _ImplicitlyDefaultConstructibleTuple()
568 {
569 return __and_<__is_implicitly_default_constructible<_Elements>...>
570 ::value;
571 }
572 };
573
574 public:
575 template<typename _Dummy = void,
576 typename enable_if<_TC2<_Dummy>::
577 _ImplicitlyDefaultConstructibleTuple(),
578 bool>::type = true>
579 constexpr tuple()
580 : _Inherited() { }
581
582 template<typename _Dummy = void,
583 typename enable_if<_TC2<_Dummy>::
584 _DefaultConstructibleTuple()
585 &&
586 !_TC2<_Dummy>::
587 _ImplicitlyDefaultConstructibleTuple(),
588 bool>::type = false>
589 explicit constexpr tuple()
590 : _Inherited() { }
591
592 // Shortcut for the cases where constructors taking _Elements...
593 // need to be constrained.
594 template<typename _Dummy> using _TCC =
595 _TC<is_same<_Dummy, void>::value,
596 _Elements...>;
597
598 template<typename _Dummy = void,
599 typename enable_if<
600 _TCC<_Dummy>::template
601 _ConstructibleTuple<_Elements...>()
602 && _TCC<_Dummy>::template
603 _ImplicitlyConvertibleTuple<_Elements...>()
604 && (sizeof...(_Elements) >= 1),
605 bool>::type=true>
606 constexpr tuple(const _Elements&... __elements)
607 : _Inherited(__elements...) { }
608
609 template<typename _Dummy = void,
610 typename enable_if<
611 _TCC<_Dummy>::template
612 _ConstructibleTuple<_Elements...>()
613 && !_TCC<_Dummy>::template
614 _ImplicitlyConvertibleTuple<_Elements...>()
615 && (sizeof...(_Elements) >= 1),
616 bool>::type=false>
617 explicit constexpr tuple(const _Elements&... __elements)
618 : _Inherited(__elements...) { }
619
620 // Shortcut for the cases where constructors taking _UElements...
621 // need to be constrained.
622 template<typename... _UElements> using _TMC =
623 _TC<(sizeof...(_Elements) == sizeof...(_UElements)),
624 _Elements...>;
625
626 template<typename... _UElements, typename
627 enable_if<
628 _TC<sizeof...(_UElements) == 1, _Elements...>::template
629 _NotSameTuple<_UElements...>()
630 && _TMC<_UElements...>::template
631 _MoveConstructibleTuple<_UElements...>()
632 && _TMC<_UElements...>::template
633 _ImplicitlyMoveConvertibleTuple<_UElements...>()
634 && (sizeof...(_Elements) >= 1),
635 bool>::type=true>
636 constexpr tuple(_UElements&&... __elements)
637 : _Inherited(std::forward<_UElements>(__elements)...) { }
638
639 template<typename... _UElements, typename
640 enable_if<
641 _TC<sizeof...(_UElements) == 1, _Elements...>::template
642 _NotSameTuple<_UElements...>()
643 && _TMC<_UElements...>::template
644 _MoveConstructibleTuple<_UElements...>()
645 && !_TMC<_UElements...>::template
646 _ImplicitlyMoveConvertibleTuple<_UElements...>()
647 && (sizeof...(_Elements) >= 1),
648 bool>::type=false>
649 explicit constexpr tuple(_UElements&&... __elements)
650 : _Inherited(std::forward<_UElements>(__elements)...) { }
651
652 constexpr tuple(const tuple&) = default;
653
654 constexpr tuple(tuple&&) = default;
655
656 // Shortcut for the cases where constructors taking tuples
657 // must avoid creating temporaries.
658 template<typename _Dummy> using _TNTC =
659 _TC<is_same<_Dummy, void>::value && sizeof...(_Elements) == 1,
660 _Elements...>;
661
662 template<typename... _UElements, typename _Dummy = void, typename
663 enable_if<_TMC<_UElements...>::template
664 _ConstructibleTuple<_UElements...>()
665 && _TMC<_UElements...>::template
666 _ImplicitlyConvertibleTuple<_UElements...>()
667 && _TNTC<_Dummy>::template
668 _NonNestedTuple<const tuple<_UElements...>&>(),
669 bool>::type=true>
670 constexpr tuple(const tuple<_UElements...>& __in)
671 : _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
672 { }
673
674 template<typename... _UElements, typename _Dummy = void, typename
675 enable_if<_TMC<_UElements...>::template
676 _ConstructibleTuple<_UElements...>()
677 && !_TMC<_UElements...>::template
678 _ImplicitlyConvertibleTuple<_UElements...>()
679 && _TNTC<_Dummy>::template
680 _NonNestedTuple<const tuple<_UElements...>&>(),
681 bool>::type=false>
682 explicit constexpr tuple(const tuple<_UElements...>& __in)
683 : _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
684 { }
685
686 template<typename... _UElements, typename _Dummy = void, typename
687 enable_if<_TMC<_UElements...>::template
688 _MoveConstructibleTuple<_UElements...>()
689 && _TMC<_UElements...>::template
690 _ImplicitlyMoveConvertibleTuple<_UElements...>()
691 && _TNTC<_Dummy>::template
692 _NonNestedTuple<tuple<_UElements...>&&>(),
693 bool>::type=true>
694 constexpr tuple(tuple<_UElements...>&& __in)
695 : _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
696
697 template<typename... _UElements, typename _Dummy = void, typename
698 enable_if<_TMC<_UElements...>::template
699 _MoveConstructibleTuple<_UElements...>()
700 && !_TMC<_UElements...>::template
701 _ImplicitlyMoveConvertibleTuple<_UElements...>()
702 && _TNTC<_Dummy>::template
703 _NonNestedTuple<tuple<_UElements...>&&>(),
704 bool>::type=false>
705 explicit constexpr tuple(tuple<_UElements...>&& __in)
706 : _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
707
708 // Allocator-extended constructors.
709
710 template<typename _Alloc>
711 tuple(allocator_arg_t __tag, const _Alloc& __a)
712 : _Inherited(__tag, __a) { }
713
714 template<typename _Alloc, typename _Dummy = void,
715 typename enable_if<
716 _TCC<_Dummy>::template
717 _ConstructibleTuple<_Elements...>()
718 && _TCC<_Dummy>::template
719 _ImplicitlyConvertibleTuple<_Elements...>(),
720 bool>::type=true>
721 tuple(allocator_arg_t __tag, const _Alloc& __a,
722 const _Elements&... __elements)
723 : _Inherited(__tag, __a, __elements...) { }
724
725 template<typename _Alloc, typename _Dummy = void,
726 typename enable_if<
727 _TCC<_Dummy>::template
728 _ConstructibleTuple<_Elements...>()
729 && !_TCC<_Dummy>::template
730 _ImplicitlyConvertibleTuple<_Elements...>(),
731 bool>::type=false>
732 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
733 const _Elements&... __elements)
734 : _Inherited(__tag, __a, __elements...) { }
735
736 template<typename _Alloc, typename... _UElements, typename
737 enable_if<_TMC<_UElements...>::template
738 _MoveConstructibleTuple<_UElements...>()
739 && _TMC<_UElements...>::template
740 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
741 bool>::type=true>
742 tuple(allocator_arg_t __tag, const _Alloc& __a,
743 _UElements&&... __elements)
744 : _Inherited(__tag, __a, std::forward<_UElements>(__elements)...)
745 { }
746
747 template<typename _Alloc, typename... _UElements, typename
748 enable_if<_TMC<_UElements...>::template
749 _MoveConstructibleTuple<_UElements...>()
750 && !_TMC<_UElements...>::template
751 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
752 bool>::type=false>
753 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
754 _UElements&&... __elements)
755 : _Inherited(__tag, __a, std::forward<_UElements>(__elements)...)
756 { }
757
758 template<typename _Alloc>
759 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
760 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
761
762 template<typename _Alloc>
763 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
764 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
765
766 template<typename _Alloc, typename... _UElements, typename
767 enable_if<_TMC<_UElements...>::template
768 _ConstructibleTuple<_UElements...>()
769 && _TMC<_UElements...>::template
770 _ImplicitlyConvertibleTuple<_UElements...>(),
771 bool>::type=true>
772 tuple(allocator_arg_t __tag, const _Alloc& __a,
773 const tuple<_UElements...>& __in)
774 : _Inherited(__tag, __a,
775 static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
776 { }
777
778 template<typename _Alloc, typename... _UElements, typename
779 enable_if<_TMC<_UElements...>::template
780 _ConstructibleTuple<_UElements...>()
781 && !_TMC<_UElements...>::template
782 _ImplicitlyConvertibleTuple<_UElements...>(),
783 bool>::type=false>
784 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
785 const tuple<_UElements...>& __in)
786 : _Inherited(__tag, __a,
787 static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
788 { }
789
790 template<typename _Alloc, typename... _UElements, typename
791 enable_if<_TMC<_UElements...>::template
792 _MoveConstructibleTuple<_UElements...>()
793 && _TMC<_UElements...>::template
794 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
795 bool>::type=true>
796 tuple(allocator_arg_t __tag, const _Alloc& __a,
797 tuple<_UElements...>&& __in)
798 : _Inherited(__tag, __a,
799 static_cast<_Tuple_impl<0, _UElements...>&&>(__in))
800 { }
801
802 template<typename _Alloc, typename... _UElements, typename
803 enable_if<_TMC<_UElements...>::template
804 _MoveConstructibleTuple<_UElements...>()
805 && !_TMC<_UElements...>::template
806 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
807 bool>::type=false>
808 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
809 tuple<_UElements...>&& __in)
810 : _Inherited(__tag, __a,
811 static_cast<_Tuple_impl<0, _UElements...>&&>(__in))
812 { }
813
814 tuple&
815 operator=(const tuple& __in)
816 {
817 static_cast<_Inherited&>(*this) = __in;
818 return *this;
819 }
820
821 tuple&
822 operator=(tuple&& __in)
823 noexcept(is_nothrow_move_assignable<_Inherited>::value)
824 {
825 static_cast<_Inherited&>(*this) = std::move(__in);
826 return *this;
827 }
828
829 template<typename... _UElements, typename = typename
830 enable_if<sizeof...(_UElements)
831 == sizeof...(_Elements)>::type>
832 tuple&
833 operator=(const tuple<_UElements...>& __in)
834 {
835 static_cast<_Inherited&>(*this) = __in;
836 return *this;
837 }
838
839 template<typename... _UElements, typename = typename
840 enable_if<sizeof...(_UElements)
841 == sizeof...(_Elements)>::type>
842 tuple&
843 operator=(tuple<_UElements...>&& __in)
844 {
845 static_cast<_Inherited&>(*this) = std::move(__in);
846 return *this;
847 }
848
849 void
850 swap(tuple& __in)
851 noexcept(noexcept(__in._M_swap(__in)))
852 { _Inherited::_M_swap(__in); }
853 };
854
855 // Explicit specialization, zero-element tuple.
856 template<>
857 class tuple<>
858 {
859 public:
860 void swap(tuple&) noexcept { /* no-op */ }
861 };
862
863 /// Partial specialization, 2-element tuple.
864 /// Includes construction and assignment from a pair.
865 template<typename _T1, typename _T2>
866 class tuple<_T1, _T2> : public _Tuple_impl<0, _T1, _T2>
867 {
868 typedef _Tuple_impl<0, _T1, _T2> _Inherited;
869
870 public:
871 template <typename _U1 = _T1,
872 typename _U2 = _T2,
873 typename enable_if<__and_<
874 __is_implicitly_default_constructible<_U1>,
875 __is_implicitly_default_constructible<_U2>>
876 ::value, bool>::type = true>
877
878 constexpr tuple()
879 : _Inherited() { }
880
881 template <typename _U1 = _T1,
882 typename _U2 = _T2,
883 typename enable_if<
884 __and_<
885 is_default_constructible<_U1>,
886 is_default_constructible<_U2>,
887 __not_<
888 __and_<__is_implicitly_default_constructible<_U1>,
889 __is_implicitly_default_constructible<_U2>>>>
890 ::value, bool>::type = false>
891
892 explicit constexpr tuple()
893 : _Inherited() { }
894
895 // Shortcut for the cases where constructors taking _T1, _T2
896 // need to be constrained.
897 template<typename _Dummy> using _TCC =
898 _TC<is_same<_Dummy, void>::value, _T1, _T2>;
899
900 template<typename _Dummy = void, typename
901 enable_if<_TCC<_Dummy>::template
902 _ConstructibleTuple<_T1, _T2>()
903 && _TCC<_Dummy>::template
904 _ImplicitlyConvertibleTuple<_T1, _T2>(),
905 bool>::type = true>
906 constexpr tuple(const _T1& __a1, const _T2& __a2)
907 : _Inherited(__a1, __a2) { }
908
909 template<typename _Dummy = void, typename
910 enable_if<_TCC<_Dummy>::template
911 _ConstructibleTuple<_T1, _T2>()
912 && !_TCC<_Dummy>::template
913 _ImplicitlyConvertibleTuple<_T1, _T2>(),
914 bool>::type = false>
915 explicit constexpr tuple(const _T1& __a1, const _T2& __a2)
916 : _Inherited(__a1, __a2) { }
917
918 // Shortcut for the cases where constructors taking _U1, _U2
919 // need to be constrained.
920 using _TMC = _TC<true, _T1, _T2>;
921
922 template<typename _U1, typename _U2, typename
923 enable_if<_TMC::template
924 _MoveConstructibleTuple<_U1, _U2>()
925 && _TMC::template
926 _ImplicitlyMoveConvertibleTuple<_U1, _U2>()
927 && !is_same<typename decay<_U1>::type,
928 allocator_arg_t>::value,
929 bool>::type = true>
930 constexpr tuple(_U1&& __a1, _U2&& __a2)
931 : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
932
933 template<typename _U1, typename _U2, typename
934 enable_if<_TMC::template
935 _MoveConstructibleTuple<_U1, _U2>()
936 && !_TMC::template
937 _ImplicitlyMoveConvertibleTuple<_U1, _U2>()
938 && !is_same<typename decay<_U1>::type,
939 allocator_arg_t>::value,
940 bool>::type = false>
941 explicit constexpr tuple(_U1&& __a1, _U2&& __a2)
942 : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
943
944 constexpr tuple(const tuple&) = default;
945
946 constexpr tuple(tuple&&) = default;
947
948 template<typename _U1, typename _U2, typename
949 enable_if<_TMC::template
950 _ConstructibleTuple<_U1, _U2>()
951 && _TMC::template
952 _ImplicitlyConvertibleTuple<_U1, _U2>(),
953 bool>::type = true>
954 constexpr tuple(const tuple<_U1, _U2>& __in)
955 : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
956
957 template<typename _U1, typename _U2, typename
958 enable_if<_TMC::template
959 _ConstructibleTuple<_U1, _U2>()
960 && !_TMC::template
961 _ImplicitlyConvertibleTuple<_U1, _U2>(),
962 bool>::type = false>
963 explicit constexpr tuple(const tuple<_U1, _U2>& __in)
964 : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
965
966 template<typename _U1, typename _U2, typename
967 enable_if<_TMC::template
968 _MoveConstructibleTuple<_U1, _U2>()
969 && _TMC::template
970 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
971 bool>::type = true>
972 constexpr tuple(tuple<_U1, _U2>&& __in)
973 : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
974
975 template<typename _U1, typename _U2, typename
976 enable_if<_TMC::template
977 _MoveConstructibleTuple<_U1, _U2>()
978 && !_TMC::template
979 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
980 bool>::type = false>
981 explicit constexpr tuple(tuple<_U1, _U2>&& __in)
982 : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
983
984 template<typename _U1, typename _U2, typename
985 enable_if<_TMC::template
986 _ConstructibleTuple<_U1, _U2>()
987 && _TMC::template
988 _ImplicitlyConvertibleTuple<_U1, _U2>(),
989 bool>::type = true>
990 constexpr tuple(const pair<_U1, _U2>& __in)
991 : _Inherited(__in.first, __in.second) { }
992
993 template<typename _U1, typename _U2, typename
994 enable_if<_TMC::template
995 _ConstructibleTuple<_U1, _U2>()
996 && !_TMC::template
997 _ImplicitlyConvertibleTuple<_U1, _U2>(),
998 bool>::type = false>
999 explicit constexpr tuple(const pair<_U1, _U2>& __in)
1000 : _Inherited(__in.first, __in.second) { }
1001
1002 template<typename _U1, typename _U2, typename
1003 enable_if<_TMC::template
1004 _MoveConstructibleTuple<_U1, _U2>()
1005 && _TMC::template
1006 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1007 bool>::type = true>
1008 constexpr tuple(pair<_U1, _U2>&& __in)
1009 : _Inherited(std::forward<_U1>(__in.first),
1010 std::forward<_U2>(__in.second)) { }
1011
1012 template<typename _U1, typename _U2, typename
1013 enable_if<_TMC::template
1014 _MoveConstructibleTuple<_U1, _U2>()
1015 && !_TMC::template
1016 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1017 bool>::type = false>
1018 explicit constexpr tuple(pair<_U1, _U2>&& __in)
1019 : _Inherited(std::forward<_U1>(__in.first),
1020 std::forward<_U2>(__in.second)) { }
1021
1022 // Allocator-extended constructors.
1023
1024 template<typename _Alloc>
1025 tuple(allocator_arg_t __tag, const _Alloc& __a)
1026 : _Inherited(__tag, __a) { }
1027
1028 template<typename _Alloc, typename _Dummy = void,
1029 typename enable_if<
1030 _TCC<_Dummy>::template
1031 _ConstructibleTuple<_T1, _T2>()
1032 && _TCC<_Dummy>::template
1033 _ImplicitlyConvertibleTuple<_T1, _T2>(),
1034 bool>::type=true>
1035
1036 tuple(allocator_arg_t __tag, const _Alloc& __a,
1037 const _T1& __a1, const _T2& __a2)
1038 : _Inherited(__tag, __a, __a1, __a2) { }
1039
1040 template<typename _Alloc, typename _Dummy = void,
1041 typename enable_if<
1042 _TCC<_Dummy>::template
1043 _ConstructibleTuple<_T1, _T2>()
1044 && !_TCC<_Dummy>::template
1045 _ImplicitlyConvertibleTuple<_T1, _T2>(),
1046 bool>::type=false>
1047
1048 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1049 const _T1& __a1, const _T2& __a2)
1050 : _Inherited(__tag, __a, __a1, __a2) { }
1051
1052 template<typename _Alloc, typename _U1, typename _U2, typename
1053 enable_if<_TMC::template
1054 _MoveConstructibleTuple<_U1, _U2>()
1055 && _TMC::template
1056 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1057 bool>::type = true>
1058 tuple(allocator_arg_t __tag, const _Alloc& __a, _U1&& __a1, _U2&& __a2)
1059 : _Inherited(__tag, __a, std::forward<_U1>(__a1),
1060 std::forward<_U2>(__a2)) { }
1061
1062 template<typename _Alloc, typename _U1, typename _U2, typename
1063 enable_if<_TMC::template
1064 _MoveConstructibleTuple<_U1, _U2>()
1065 && !_TMC::template
1066 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1067 bool>::type = false>
1068 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1069 _U1&& __a1, _U2&& __a2)
1070 : _Inherited(__tag, __a, std::forward<_U1>(__a1),
1071 std::forward<_U2>(__a2)) { }
1072
1073 template<typename _Alloc>
1074 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
1075 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
1076
1077 template<typename _Alloc>
1078 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
1079 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
1080
1081 template<typename _Alloc, typename _U1, typename _U2, typename
1082 enable_if<_TMC::template
1083 _ConstructibleTuple<_U1, _U2>()
1084 && _TMC::template
1085 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1086 bool>::type = true>
1087 tuple(allocator_arg_t __tag, const _Alloc& __a,
1088 const tuple<_U1, _U2>& __in)
1089 : _Inherited(__tag, __a,
1090 static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in))
1091 { }
1092
1093 template<typename _Alloc, typename _U1, typename _U2, typename
1094 enable_if<_TMC::template
1095 _ConstructibleTuple<_U1, _U2>()
1096 && !_TMC::template
1097 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1098 bool>::type = false>
1099 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1100 const tuple<_U1, _U2>& __in)
1101 : _Inherited(__tag, __a,
1102 static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in))
1103 { }
1104
1105 template<typename _Alloc, typename _U1, typename _U2, typename
1106 enable_if<_TMC::template
1107 _MoveConstructibleTuple<_U1, _U2>()
1108 && _TMC::template
1109 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1110 bool>::type = true>
1111 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple<_U1, _U2>&& __in)
1112 : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in))
1113 { }
1114
1115 template<typename _Alloc, typename _U1, typename _U2, typename
1116 enable_if<_TMC::template
1117 _MoveConstructibleTuple<_U1, _U2>()
1118 && !_TMC::template
1119 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1120 bool>::type = false>
1121 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1122 tuple<_U1, _U2>&& __in)
1123 : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in))
1124 { }
1125
1126 template<typename _Alloc, typename _U1, typename _U2, typename
1127 enable_if<_TMC::template
1128 _ConstructibleTuple<_U1, _U2>()
1129 && _TMC::template
1130 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1131 bool>::type = true>
1132 tuple(allocator_arg_t __tag, const _Alloc& __a,
1133 const pair<_U1, _U2>& __in)
1134 : _Inherited(__tag, __a, __in.first, __in.second) { }
1135
1136 template<typename _Alloc, typename _U1, typename _U2, typename
1137 enable_if<_TMC::template
1138 _ConstructibleTuple<_U1, _U2>()
1139 && !_TMC::template
1140 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1141 bool>::type = false>
1142 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1143 const pair<_U1, _U2>& __in)
1144 : _Inherited(__tag, __a, __in.first, __in.second) { }
1145
1146 template<typename _Alloc, typename _U1, typename _U2, typename
1147 enable_if<_TMC::template
1148 _MoveConstructibleTuple<_U1, _U2>()
1149 && _TMC::template
1150 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1151 bool>::type = true>
1152 tuple(allocator_arg_t __tag, const _Alloc& __a, pair<_U1, _U2>&& __in)
1153 : _Inherited(__tag, __a, std::forward<_U1>(__in.first),
1154 std::forward<_U2>(__in.second)) { }
1155
1156 template<typename _Alloc, typename _U1, typename _U2, typename
1157 enable_if<_TMC::template
1158 _MoveConstructibleTuple<_U1, _U2>()
1159 && !_TMC::template
1160 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1161 bool>::type = false>
1162 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1163 pair<_U1, _U2>&& __in)
1164 : _Inherited(__tag, __a, std::forward<_U1>(__in.first),
1165 std::forward<_U2>(__in.second)) { }
1166
1167 tuple&
1168 operator=(const tuple& __in)
1169 {
1170 static_cast<_Inherited&>(*this) = __in;
1171 return *this;
1172 }
1173
1174 tuple&
1175 operator=(tuple&& __in)
1176 noexcept(is_nothrow_move_assignable<_Inherited>::value)
1177 {
1178 static_cast<_Inherited&>(*this) = std::move(__in);
1179 return *this;
1180 }
1181
1182 template<typename _U1, typename _U2>
1183 tuple&
1184 operator=(const tuple<_U1, _U2>& __in)
1185 {
1186 static_cast<_Inherited&>(*this) = __in;
1187 return *this;
1188 }
1189
1190 template<typename _U1, typename _U2>
1191 tuple&
1192 operator=(tuple<_U1, _U2>&& __in)
1193 {
1194 static_cast<_Inherited&>(*this) = std::move(__in);
1195 return *this;
1196 }
1197
1198 template<typename _U1, typename _U2>
1199 tuple&
1200 operator=(const pair<_U1, _U2>& __in)
1201 {
1202 this->_M_head(*this) = __in.first;
1203 this->_M_tail(*this)._M_head(*this) = __in.second;
1204 return *this;
1205 }
1206
1207 template<typename _U1, typename _U2>
1208 tuple&
1209 operator=(pair<_U1, _U2>&& __in)
1210 {
1211 this->_M_head(*this) = std::forward<_U1>(__in.first);
1212 this->_M_tail(*this)._M_head(*this) = std::forward<_U2>(__in.second);
1213 return *this;
1214 }
1215
1216 void
1217 swap(tuple& __in)
1218 noexcept(noexcept(__in._M_swap(__in)))
1219 { _Inherited::_M_swap(__in); }
1220 };
1221
1222
1223 /**
1224 * Recursive case for tuple_element: strip off the first element in
1225 * the tuple and retrieve the (i-1)th element of the remaining tuple.
1226 */
1227 template<std::size_t __i, typename _Head, typename... _Tail>
1228 struct tuple_element<__i, tuple<_Head, _Tail...> >
1229 : tuple_element<__i - 1, tuple<_Tail...> > { };
1230
1231 /**
1232 * Basis case for tuple_element: The first element is the one we're seeking.
1233 */
1234 template<typename _Head, typename... _Tail>
1235 struct tuple_element<0, tuple<_Head, _Tail...> >
1236 {
1237 typedef _Head type;
1238 };
1239
1240 /// class tuple_size
1241 template<typename... _Elements>
1242 struct tuple_size<tuple<_Elements...>>
1243 : public integral_constant<std::size_t, sizeof...(_Elements)> { };
1244
1245 template<std::size_t __i, typename _Head, typename... _Tail>
1246 constexpr _Head&
1247 __get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1248 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
1249
1250 template<std::size_t __i, typename _Head, typename... _Tail>
1251 constexpr const _Head&
1252 __get_helper(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1253 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
10
Calling '_Tuple_impl::_M_head'
15
Returning from '_Tuple_impl::_M_head'
16
Returning pointer (reference to field '_M_head_impl')
1254
1255 /// Return a reference to the ith element of a tuple.
1256 template<std::size_t __i, typename... _Elements>
1257 constexpr __tuple_element_t<__i, tuple<_Elements...>>&
1258 get(tuple<_Elements...>& __t) noexcept
1259 { return std::__get_helper<__i>(__t); }
1260
1261 /// Return a const reference to the ith element of a const tuple.
1262 template<std::size_t __i, typename... _Elements>
1263 constexpr const __tuple_element_t<__i, tuple<_Elements...>>&
1264 get(const tuple<_Elements...>& __t) noexcept
1265 { return std::__get_helper<__i>(__t); }
9
Calling '__get_helper<0, llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > *, std::default_delete<llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > >>'
17
Returning from '__get_helper<0, llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > *, std::default_delete<llvm::iplist<llvm::MemoryAccess, llvm::ilist_tag<llvm::MSSAHelpers::AllAccessTag> > >>'
18
Returning pointer (reference to field '_M_head_impl')
1266
1267 /// Return an rvalue reference to the ith element of a tuple rvalue.
1268 template<std::size_t __i, typename... _Elements>
1269 constexpr __tuple_element_t<__i, tuple<_Elements...>>&&
1270 get(tuple<_Elements...>&& __t) noexcept
1271 {
1272 typedef __tuple_element_t<__i, tuple<_Elements...>> __element_type;
1273 return std::forward<__element_type&&>(std::get<__i>(__t));
1274 }
1275
1276#if __cplusplus201103L > 201103L
1277
1278#define __cpp_lib_tuples_by_type 201304
1279
1280 template<typename _Head, size_t __i, typename... _Tail>
1281 constexpr _Head&
1282 __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1283 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
1284
1285 template<typename _Head, size_t __i, typename... _Tail>
1286 constexpr const _Head&
1287 __get_helper2(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1288 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }