LLVM 19.0.0git
Attributor.cpp
Go to the documentation of this file.
1//===- Attributor.cpp - Module-wide attribute deduction -------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements an interprocedural pass that deduces and/or propagates
10// attributes. This is done in an abstract interpretation style fixpoint
11// iteration. See the Attributor.h file comment and the class descriptions in
12// that file for more information.
13//
14//===----------------------------------------------------------------------===//
15
17
18#include "llvm/ADT/ArrayRef.h"
20#include "llvm/ADT/STLExtras.h"
22#include "llvm/ADT/Statistic.h"
30#include "llvm/IR/Attributes.h"
31#include "llvm/IR/Constant.h"
33#include "llvm/IR/Constants.h"
34#include "llvm/IR/DataLayout.h"
35#include "llvm/IR/GlobalValue.h"
37#include "llvm/IR/Instruction.h"
40#include "llvm/IR/LLVMContext.h"
41#include "llvm/IR/ValueHandle.h"
44#include "llvm/Support/Debug.h"
48#include "llvm/Support/ModRef.h"
53#include <cstdint>
54#include <memory>
55
56#ifdef EXPENSIVE_CHECKS
57#include "llvm/IR/Verifier.h"
58#endif
59
60#include <cassert>
61#include <optional>
62#include <string>
63
64using namespace llvm;
65
66#define DEBUG_TYPE "attributor"
67#define VERBOSE_DEBUG_TYPE DEBUG_TYPE "-verbose"
68
69DEBUG_COUNTER(ManifestDBGCounter, "attributor-manifest",
70 "Determine what attributes are manifested in the IR");
71
72STATISTIC(NumFnDeleted, "Number of function deleted");
73STATISTIC(NumFnWithExactDefinition,
74 "Number of functions with exact definitions");
75STATISTIC(NumFnWithoutExactDefinition,
76 "Number of functions without exact definitions");
77STATISTIC(NumFnShallowWrappersCreated, "Number of shallow wrappers created");
78STATISTIC(NumAttributesTimedOut,
79 "Number of abstract attributes timed out before fixpoint");
80STATISTIC(NumAttributesValidFixpoint,
81 "Number of abstract attributes in a valid fixpoint state");
82STATISTIC(NumAttributesManifested,
83 "Number of abstract attributes manifested in IR");
84
85// TODO: Determine a good default value.
86//
87// In the LLVM-TS and SPEC2006, 32 seems to not induce compile time overheads
88// (when run with the first 5 abstract attributes). The results also indicate
89// that we never reach 32 iterations but always find a fixpoint sooner.
90//
91// This will become more evolved once we perform two interleaved fixpoint
92// iterations: bottom-up and top-down.
94 SetFixpointIterations("attributor-max-iterations", cl::Hidden,
95 cl::desc("Maximal number of fixpoint iterations."),
96 cl::init(32));
97
99 MaxSpecializationPerCB("attributor-max-specializations-per-call-base",
101 cl::desc("Maximal number of callees specialized for "
102 "a call base"),
103 cl::init(UINT32_MAX));
104
106 "attributor-max-initialization-chain-length", cl::Hidden,
107 cl::desc(
108 "Maximal number of chained initializations (to avoid stack overflows)"),
111
113 "attributor-annotate-decl-cs", cl::Hidden,
114 cl::desc("Annotate call sites of function declarations."), cl::init(false));
115
116static cl::opt<bool> EnableHeapToStack("enable-heap-to-stack-conversion",
117 cl::init(true), cl::Hidden);
118
119static cl::opt<bool>
120 AllowShallowWrappers("attributor-allow-shallow-wrappers", cl::Hidden,
121 cl::desc("Allow the Attributor to create shallow "
122 "wrappers for non-exact definitions."),
123 cl::init(false));
124
125static cl::opt<bool>
126 AllowDeepWrapper("attributor-allow-deep-wrappers", cl::Hidden,
127 cl::desc("Allow the Attributor to use IP information "
128 "derived from non-exact functions via cloning"),
129 cl::init(false));
130
131// These options can only used for debug builds.
132#ifndef NDEBUG
134 SeedAllowList("attributor-seed-allow-list", cl::Hidden,
135 cl::desc("Comma separated list of attribute names that are "
136 "allowed to be seeded."),
138
140 "attributor-function-seed-allow-list", cl::Hidden,
141 cl::desc("Comma separated list of function names that are "
142 "allowed to be seeded."),
144#endif
145
146static cl::opt<bool>
147 DumpDepGraph("attributor-dump-dep-graph", cl::Hidden,
148 cl::desc("Dump the dependency graph to dot files."),
149 cl::init(false));
150
152 "attributor-depgraph-dot-filename-prefix", cl::Hidden,
153 cl::desc("The prefix used for the CallGraph dot file names."));
154
155static cl::opt<bool> ViewDepGraph("attributor-view-dep-graph", cl::Hidden,
156 cl::desc("View the dependency graph."),
157 cl::init(false));
158
159static cl::opt<bool> PrintDependencies("attributor-print-dep", cl::Hidden,
160 cl::desc("Print attribute dependencies"),
161 cl::init(false));
162
164 "attributor-enable-call-site-specific-deduction", cl::Hidden,
165 cl::desc("Allow the Attributor to do call site specific analysis"),
166 cl::init(false));
167
168static cl::opt<bool>
169 PrintCallGraph("attributor-print-call-graph", cl::Hidden,
170 cl::desc("Print Attributor's internal call graph"),
171 cl::init(false));
172
173static cl::opt<bool> SimplifyAllLoads("attributor-simplify-all-loads",
175 cl::desc("Try to simplify all loads."),
176 cl::init(true));
177
179 "attributor-assume-closed-world", cl::Hidden,
180 cl::desc("Should a closed world be assumed, or not. Default if not set."));
181
182/// Logic operators for the change status enum class.
183///
184///{
186 return L == ChangeStatus::CHANGED ? L : R;
187}
189 L = L | R;
190 return L;
191}
193 return L == ChangeStatus::UNCHANGED ? L : R;
194}
196 L = L & R;
197 return L;
198}
199///}
200
201bool AA::isGPU(const Module &M) {
202 Triple T(M.getTargetTriple());
203 return T.isAMDGPU() || T.isNVPTX();
204}
205
207 const AbstractAttribute &QueryingAA) {
208 // We are looking for volatile instructions or non-relaxed atomics.
209 if (const auto *CB = dyn_cast<CallBase>(&I)) {
210 if (CB->hasFnAttr(Attribute::NoSync))
211 return true;
212
213 // Non-convergent and readnone imply nosync.
214 if (!CB->isConvergent() && !CB->mayReadOrWriteMemory())
215 return true;
216
218 return true;
219
220 bool IsKnownNoSync;
221 return AA::hasAssumedIRAttr<Attribute::NoSync>(
222 A, &QueryingAA, IRPosition::callsite_function(*CB),
223 DepClassTy::OPTIONAL, IsKnownNoSync);
224 }
225
226 if (!I.mayReadOrWriteMemory())
227 return true;
228
229 return !I.isVolatile() && !AANoSync::isNonRelaxedAtomic(&I);
230}
231
233 const Value &V, bool ForAnalysisOnly) {
234 // TODO: See the AAInstanceInfo class comment.
235 if (!ForAnalysisOnly)
236 return false;
237 auto *InstanceInfoAA = A.getAAFor<AAInstanceInfo>(
238 QueryingAA, IRPosition::value(V), DepClassTy::OPTIONAL);
239 return InstanceInfoAA && InstanceInfoAA->isAssumedUniqueForAnalysis();
240}
241
242Constant *
244 Value &Obj, Type &Ty, const TargetLibraryInfo *TLI,
245 const DataLayout &DL, AA::RangeTy *RangePtr) {
246 if (isa<AllocaInst>(Obj))
247 return UndefValue::get(&Ty);
248 if (Constant *Init = getInitialValueOfAllocation(&Obj, TLI, &Ty))
249 return Init;
250 auto *GV = dyn_cast<GlobalVariable>(&Obj);
251 if (!GV)
252 return nullptr;
253
254 bool UsedAssumedInformation = false;
255 Constant *Initializer = nullptr;
256 if (A.hasGlobalVariableSimplificationCallback(*GV)) {
257 auto AssumedGV = A.getAssumedInitializerFromCallBack(
258 *GV, &QueryingAA, UsedAssumedInformation);
259 Initializer = *AssumedGV;
260 if (!Initializer)
261 return nullptr;
262 } else {
263 if (!GV->hasLocalLinkage() &&
264 (GV->isInterposable() || !(GV->isConstant() && GV->hasInitializer())))
265 return nullptr;
266 if (!GV->hasInitializer())
267 return UndefValue::get(&Ty);
268
269 if (!Initializer)
270 Initializer = GV->getInitializer();
271 }
272
273 if (RangePtr && !RangePtr->offsetOrSizeAreUnknown()) {
274 APInt Offset = APInt(64, RangePtr->Offset);
275 return ConstantFoldLoadFromConst(Initializer, &Ty, Offset, DL);
276 }
277
278 return ConstantFoldLoadFromUniformValue(Initializer, &Ty, DL);
279}
280
281bool AA::isValidInScope(const Value &V, const Function *Scope) {
282 if (isa<Constant>(V))
283 return true;
284 if (auto *I = dyn_cast<Instruction>(&V))
285 return I->getFunction() == Scope;
286 if (auto *A = dyn_cast<Argument>(&V))
287 return A->getParent() == Scope;
288 return false;
289}
290
292 InformationCache &InfoCache) {
293 if (isa<Constant>(VAC.getValue()) || VAC.getValue() == VAC.getCtxI())
294 return true;
295 const Function *Scope = nullptr;
296 const Instruction *CtxI = VAC.getCtxI();
297 if (CtxI)
298 Scope = CtxI->getFunction();
299 if (auto *A = dyn_cast<Argument>(VAC.getValue()))
300 return A->getParent() == Scope;
301 if (auto *I = dyn_cast<Instruction>(VAC.getValue())) {
302 if (I->getFunction() == Scope) {
303 if (const DominatorTree *DT =
305 *Scope))
306 return DT->dominates(I, CtxI);
307 // Local dominance check mostly for the old PM passes.
308 if (CtxI && I->getParent() == CtxI->getParent())
309 return llvm::any_of(
310 make_range(I->getIterator(), I->getParent()->end()),
311 [&](const Instruction &AfterI) { return &AfterI == CtxI; });
312 }
313 }
314 return false;
315}
316
318 if (V.getType() == &Ty)
319 return &V;
320 if (isa<PoisonValue>(V))
321 return PoisonValue::get(&Ty);
322 if (isa<UndefValue>(V))
323 return UndefValue::get(&Ty);
324 if (auto *C = dyn_cast<Constant>(&V)) {
325 if (C->isNullValue())
326 return Constant::getNullValue(&Ty);
327 if (C->getType()->isPointerTy() && Ty.isPointerTy())
328 return ConstantExpr::getPointerCast(C, &Ty);
329 if (C->getType()->getPrimitiveSizeInBits() >= Ty.getPrimitiveSizeInBits()) {
330 if (C->getType()->isIntegerTy() && Ty.isIntegerTy())
331 return ConstantExpr::getTrunc(C, &Ty, /* OnlyIfReduced */ true);
332 if (C->getType()->isFloatingPointTy() && Ty.isFloatingPointTy())
333 return ConstantFoldCastInstruction(Instruction::FPTrunc, C, &Ty);
334 }
335 }
336 return nullptr;
337}
338
339std::optional<Value *>
340AA::combineOptionalValuesInAAValueLatice(const std::optional<Value *> &A,
341 const std::optional<Value *> &B,
342 Type *Ty) {
343 if (A == B)
344 return A;
345 if (!B)
346 return A;
347 if (*B == nullptr)
348 return nullptr;
349 if (!A)
350 return Ty ? getWithType(**B, *Ty) : nullptr;
351 if (*A == nullptr)
352 return nullptr;
353 if (!Ty)
354 Ty = (*A)->getType();
355 if (isa_and_nonnull<UndefValue>(*A))
356 return getWithType(**B, *Ty);
357 if (isa<UndefValue>(*B))
358 return A;
359 if (*A && *B && *A == getWithType(**B, *Ty))
360 return A;
361 return nullptr;
362}
363
364template <bool IsLoad, typename Ty>
366 Attributor &A, Ty &I, SmallSetVector<Value *, 4> &PotentialCopies,
367 SmallSetVector<Instruction *, 4> *PotentialValueOrigins,
368 const AbstractAttribute &QueryingAA, bool &UsedAssumedInformation,
369 bool OnlyExact) {
370 LLVM_DEBUG(dbgs() << "Trying to determine the potential copies of " << I
371 << " (only exact: " << OnlyExact << ")\n";);
372
373 Value &Ptr = *I.getPointerOperand();
374 // Containers to remember the pointer infos and new copies while we are not
375 // sure that we can find all of them. If we abort we want to avoid spurious
376 // dependences and potential copies in the provided container.
380
381 const auto *TLI =
382 A.getInfoCache().getTargetLibraryInfoForFunction(*I.getFunction());
383
384 auto Pred = [&](Value &Obj) {
385 LLVM_DEBUG(dbgs() << "Visit underlying object " << Obj << "\n");
386 if (isa<UndefValue>(&Obj))
387 return true;
388 if (isa<ConstantPointerNull>(&Obj)) {
389 // A null pointer access can be undefined but any offset from null may
390 // be OK. We do not try to optimize the latter.
391 if (!NullPointerIsDefined(I.getFunction(),
392 Ptr.getType()->getPointerAddressSpace()) &&
393 A.getAssumedSimplified(Ptr, QueryingAA, UsedAssumedInformation,
394 AA::Interprocedural) == &Obj)
395 return true;
397 dbgs() << "Underlying object is a valid nullptr, giving up.\n";);
398 return false;
399 }
400 // TODO: Use assumed noalias return.
401 if (!isa<AllocaInst>(&Obj) && !isa<GlobalVariable>(&Obj) &&
402 !(IsLoad ? isAllocationFn(&Obj, TLI) : isNoAliasCall(&Obj))) {
403 LLVM_DEBUG(dbgs() << "Underlying object is not supported yet: " << Obj
404 << "\n";);
405 return false;
406 }
407 if (auto *GV = dyn_cast<GlobalVariable>(&Obj))
408 if (!GV->hasLocalLinkage() &&
409 !(GV->isConstant() && GV->hasInitializer())) {
410 LLVM_DEBUG(dbgs() << "Underlying object is global with external "
411 "linkage, not supported yet: "
412 << Obj << "\n";);
413 return false;
414 }
415
416 bool NullOnly = true;
417 bool NullRequired = false;
418 auto CheckForNullOnlyAndUndef = [&](std::optional<Value *> V,
419 bool IsExact) {
420 if (!V || *V == nullptr)
421 NullOnly = false;
422 else if (isa<UndefValue>(*V))
423 /* No op */;
424 else if (isa<Constant>(*V) && cast<Constant>(*V)->isNullValue())
425 NullRequired = !IsExact;
426 else
427 NullOnly = false;
428 };
429
430 auto AdjustWrittenValueType = [&](const AAPointerInfo::Access &Acc,
431 Value &V) {
432 Value *AdjV = AA::getWithType(V, *I.getType());
433 if (!AdjV) {
434 LLVM_DEBUG(dbgs() << "Underlying object written but stored value "
435 "cannot be converted to read type: "
436 << *Acc.getRemoteInst() << " : " << *I.getType()
437 << "\n";);
438 }
439 return AdjV;
440 };
441
442 auto SkipCB = [&](const AAPointerInfo::Access &Acc) {
443 if ((IsLoad && !Acc.isWriteOrAssumption()) || (!IsLoad && !Acc.isRead()))
444 return true;
445 if (IsLoad) {
447 return true;
448 if (PotentialValueOrigins && !isa<AssumeInst>(Acc.getRemoteInst()))
449 return false;
450 if (!Acc.isWrittenValueUnknown())
451 if (Value *V = AdjustWrittenValueType(Acc, *Acc.getWrittenValue()))
452 if (NewCopies.count(V)) {
453 NewCopyOrigins.insert(Acc.getRemoteInst());
454 return true;
455 }
456 if (auto *SI = dyn_cast<StoreInst>(Acc.getRemoteInst()))
457 if (Value *V = AdjustWrittenValueType(Acc, *SI->getValueOperand()))
458 if (NewCopies.count(V)) {
459 NewCopyOrigins.insert(Acc.getRemoteInst());
460 return true;
461 }
462 }
463 return false;
464 };
465
466 auto CheckAccess = [&](const AAPointerInfo::Access &Acc, bool IsExact) {
467 if ((IsLoad && !Acc.isWriteOrAssumption()) || (!IsLoad && !Acc.isRead()))
468 return true;
469 if (IsLoad && Acc.isWrittenValueYetUndetermined())
470 return true;
471 CheckForNullOnlyAndUndef(Acc.getContent(), IsExact);
472 if (OnlyExact && !IsExact && !NullOnly &&
473 !isa_and_nonnull<UndefValue>(Acc.getWrittenValue())) {
474 LLVM_DEBUG(dbgs() << "Non exact access " << *Acc.getRemoteInst()
475 << ", abort!\n");
476 return false;
477 }
478 if (NullRequired && !NullOnly) {
479 LLVM_DEBUG(dbgs() << "Required all `null` accesses due to non exact "
480 "one, however found non-null one: "
481 << *Acc.getRemoteInst() << ", abort!\n");
482 return false;
483 }
484 if (IsLoad) {
485 assert(isa<LoadInst>(I) && "Expected load or store instruction only!");
486 if (!Acc.isWrittenValueUnknown()) {
487 Value *V = AdjustWrittenValueType(Acc, *Acc.getWrittenValue());
488 if (!V)
489 return false;
490 NewCopies.insert(V);
491 if (PotentialValueOrigins)
492 NewCopyOrigins.insert(Acc.getRemoteInst());
493 return true;
494 }
495 auto *SI = dyn_cast<StoreInst>(Acc.getRemoteInst());
496 if (!SI) {
497 LLVM_DEBUG(dbgs() << "Underlying object written through a non-store "
498 "instruction not supported yet: "
499 << *Acc.getRemoteInst() << "\n";);
500 return false;
501 }
502 Value *V = AdjustWrittenValueType(Acc, *SI->getValueOperand());
503 if (!V)
504 return false;
505 NewCopies.insert(V);
506 if (PotentialValueOrigins)
507 NewCopyOrigins.insert(SI);
508 } else {
509 assert(isa<StoreInst>(I) && "Expected load or store instruction only!");
510 auto *LI = dyn_cast<LoadInst>(Acc.getRemoteInst());
511 if (!LI && OnlyExact) {
512 LLVM_DEBUG(dbgs() << "Underlying object read through a non-load "
513 "instruction not supported yet: "
514 << *Acc.getRemoteInst() << "\n";);
515 return false;
516 }
517 NewCopies.insert(Acc.getRemoteInst());
518 }
519 return true;
520 };
521
522 // If the value has been written to we don't need the initial value of the
523 // object.
524 bool HasBeenWrittenTo = false;
525
527 auto *PI = A.getAAFor<AAPointerInfo>(QueryingAA, IRPosition::value(Obj),
528 DepClassTy::NONE);
529 if (!PI || !PI->forallInterferingAccesses(
530 A, QueryingAA, I,
531 /* FindInterferingWrites */ IsLoad,
532 /* FindInterferingReads */ !IsLoad, CheckAccess,
533 HasBeenWrittenTo, Range, SkipCB)) {
535 dbgs()
536 << "Failed to verify all interfering accesses for underlying object: "
537 << Obj << "\n");
538 return false;
539 }
540
541 if (IsLoad && !HasBeenWrittenTo && !Range.isUnassigned()) {
542 const DataLayout &DL = A.getDataLayout();
543 Value *InitialValue = AA::getInitialValueForObj(
544 A, QueryingAA, Obj, *I.getType(), TLI, DL, &Range);
545 if (!InitialValue) {
546 LLVM_DEBUG(dbgs() << "Could not determine required initial value of "
547 "underlying object, abort!\n");
548 return false;
549 }
550 CheckForNullOnlyAndUndef(InitialValue, /* IsExact */ true);
551 if (NullRequired && !NullOnly) {
552 LLVM_DEBUG(dbgs() << "Non exact access but initial value that is not "
553 "null or undef, abort!\n");
554 return false;
555 }
556
557 NewCopies.insert(InitialValue);
558 if (PotentialValueOrigins)
559 NewCopyOrigins.insert(nullptr);
560 }
561
562 PIs.push_back(PI);
563
564 return true;
565 };
566
567 const auto *AAUO = A.getAAFor<AAUnderlyingObjects>(
568 QueryingAA, IRPosition::value(Ptr), DepClassTy::OPTIONAL);
569 if (!AAUO || !AAUO->forallUnderlyingObjects(Pred)) {
571 dbgs() << "Underlying objects stored into could not be determined\n";);
572 return false;
573 }
574
575 // Only if we were successful collection all potential copies we record
576 // dependences (on non-fix AAPointerInfo AAs). We also only then modify the
577 // given PotentialCopies container.
578 for (const auto *PI : PIs) {
579 if (!PI->getState().isAtFixpoint())
580 UsedAssumedInformation = true;
581 A.recordDependence(*PI, QueryingAA, DepClassTy::OPTIONAL);
582 }
583 PotentialCopies.insert(NewCopies.begin(), NewCopies.end());
584 if (PotentialValueOrigins)
585 PotentialValueOrigins->insert(NewCopyOrigins.begin(), NewCopyOrigins.end());
586
587 return true;
588}
589
591 Attributor &A, LoadInst &LI, SmallSetVector<Value *, 4> &PotentialValues,
592 SmallSetVector<Instruction *, 4> &PotentialValueOrigins,
593 const AbstractAttribute &QueryingAA, bool &UsedAssumedInformation,
594 bool OnlyExact) {
595 return getPotentialCopiesOfMemoryValue</* IsLoad */ true>(
596 A, LI, PotentialValues, &PotentialValueOrigins, QueryingAA,
597 UsedAssumedInformation, OnlyExact);
598}
599
601 Attributor &A, StoreInst &SI, SmallSetVector<Value *, 4> &PotentialCopies,
602 const AbstractAttribute &QueryingAA, bool &UsedAssumedInformation,
603 bool OnlyExact) {
604 return getPotentialCopiesOfMemoryValue</* IsLoad */ false>(
605 A, SI, PotentialCopies, nullptr, QueryingAA, UsedAssumedInformation,
606 OnlyExact);
607}
608
610 const AbstractAttribute &QueryingAA,
611 bool RequireReadNone, bool &IsKnown) {
612 if (RequireReadNone) {
613 if (AA::hasAssumedIRAttr<Attribute::ReadNone>(
614 A, &QueryingAA, IRP, DepClassTy::OPTIONAL, IsKnown,
615 /* IgnoreSubsumingPositions */ true))
616 return true;
617 } else if (AA::hasAssumedIRAttr<Attribute::ReadOnly>(
618 A, &QueryingAA, IRP, DepClassTy::OPTIONAL, IsKnown,
619 /* IgnoreSubsumingPositions */ true))
620 return true;
621
624 const auto *MemLocAA =
625 A.getAAFor<AAMemoryLocation>(QueryingAA, IRP, DepClassTy::NONE);
626 if (MemLocAA && MemLocAA->isAssumedReadNone()) {
627 IsKnown = MemLocAA->isKnownReadNone();
628 if (!IsKnown)
629 A.recordDependence(*MemLocAA, QueryingAA, DepClassTy::OPTIONAL);
630 return true;
631 }
632 }
633
634 const auto *MemBehaviorAA =
635 A.getAAFor<AAMemoryBehavior>(QueryingAA, IRP, DepClassTy::NONE);
636 if (MemBehaviorAA &&
637 (MemBehaviorAA->isAssumedReadNone() ||
638 (!RequireReadNone && MemBehaviorAA->isAssumedReadOnly()))) {
639 IsKnown = RequireReadNone ? MemBehaviorAA->isKnownReadNone()
640 : MemBehaviorAA->isKnownReadOnly();
641 if (!IsKnown)
642 A.recordDependence(*MemBehaviorAA, QueryingAA, DepClassTy::OPTIONAL);
643 return true;
644 }
645
646 return false;
647}
648
650 const AbstractAttribute &QueryingAA, bool &IsKnown) {
651 return isAssumedReadOnlyOrReadNone(A, IRP, QueryingAA,
652 /* RequireReadNone */ false, IsKnown);
653}
655 const AbstractAttribute &QueryingAA, bool &IsKnown) {
656 return isAssumedReadOnlyOrReadNone(A, IRP, QueryingAA,
657 /* RequireReadNone */ true, IsKnown);
658}
659
660static bool
662 const Instruction *ToI, const Function &ToFn,
663 const AbstractAttribute &QueryingAA,
664 const AA::InstExclusionSetTy *ExclusionSet,
665 std::function<bool(const Function &F)> GoBackwardsCB) {
667 dbgs() << "[AA] isPotentiallyReachable @" << ToFn.getName() << " from "
668 << FromI << " [GBCB: " << bool(GoBackwardsCB) << "][#ExS: "
669 << (ExclusionSet ? std::to_string(ExclusionSet->size()) : "none")
670 << "]\n";
671 if (ExclusionSet)
672 for (auto *ES : *ExclusionSet)
673 dbgs() << *ES << "\n";
674 });
675
676 // We know kernels (generally) cannot be called from within the module. Thus,
677 // for reachability we would need to step back from a kernel which would allow
678 // us to reach anything anyway. Even if a kernel is invoked from another
679 // kernel, values like allocas and shared memory are not accessible. We
680 // implicitly check for this situation to avoid costly lookups.
681 if (GoBackwardsCB && &ToFn != FromI.getFunction() &&
682 !GoBackwardsCB(*FromI.getFunction()) && ToFn.hasFnAttribute("kernel") &&
683 FromI.getFunction()->hasFnAttribute("kernel")) {
684 LLVM_DEBUG(dbgs() << "[AA] assume kernel cannot be reached from within the "
685 "module; success\n";);
686 return false;
687 }
688
689 // If we can go arbitrarily backwards we will eventually reach an entry point
690 // that can reach ToI. Only if a set of blocks through which we cannot go is
691 // provided, or once we track internal functions not accessible from the
692 // outside, it makes sense to perform backwards analysis in the absence of a
693 // GoBackwardsCB.
694 if (!GoBackwardsCB && !ExclusionSet) {
695 LLVM_DEBUG(dbgs() << "[AA] check @" << ToFn.getName() << " from " << FromI
696 << " is not checked backwards and does not have an "
697 "exclusion set, abort\n");
698 return true;
699 }
700
703 Worklist.push_back(&FromI);
704
705 while (!Worklist.empty()) {
706 const Instruction *CurFromI = Worklist.pop_back_val();
707 if (!Visited.insert(CurFromI).second)
708 continue;
709
710 const Function *FromFn = CurFromI->getFunction();
711 if (FromFn == &ToFn) {
712 if (!ToI)
713 return true;
714 LLVM_DEBUG(dbgs() << "[AA] check " << *ToI << " from " << *CurFromI
715 << " intraprocedurally\n");
716 const auto *ReachabilityAA = A.getAAFor<AAIntraFnReachability>(
717 QueryingAA, IRPosition::function(ToFn), DepClassTy::OPTIONAL);
718 bool Result = !ReachabilityAA || ReachabilityAA->isAssumedReachable(
719 A, *CurFromI, *ToI, ExclusionSet);
720 LLVM_DEBUG(dbgs() << "[AA] " << *CurFromI << " "
721 << (Result ? "can potentially " : "cannot ") << "reach "
722 << *ToI << " [Intra]\n");
723 if (Result)
724 return true;
725 }
726
727 bool Result = true;
728 if (!ToFn.isDeclaration() && ToI) {
729 const auto *ToReachabilityAA = A.getAAFor<AAIntraFnReachability>(
730 QueryingAA, IRPosition::function(ToFn), DepClassTy::OPTIONAL);
731 const Instruction &EntryI = ToFn.getEntryBlock().front();
732 Result = !ToReachabilityAA || ToReachabilityAA->isAssumedReachable(
733 A, EntryI, *ToI, ExclusionSet);
734 LLVM_DEBUG(dbgs() << "[AA] Entry " << EntryI << " of @" << ToFn.getName()
735 << " " << (Result ? "can potentially " : "cannot ")
736 << "reach @" << *ToI << " [ToFn]\n");
737 }
738
739 if (Result) {
740 // The entry of the ToFn can reach the instruction ToI. If the current
741 // instruction is already known to reach the ToFn.
742 const auto *FnReachabilityAA = A.getAAFor<AAInterFnReachability>(
743 QueryingAA, IRPosition::function(*FromFn), DepClassTy::OPTIONAL);
744 Result = !FnReachabilityAA || FnReachabilityAA->instructionCanReach(
745 A, *CurFromI, ToFn, ExclusionSet);
746 LLVM_DEBUG(dbgs() << "[AA] " << *CurFromI << " in @" << FromFn->getName()
747 << " " << (Result ? "can potentially " : "cannot ")
748 << "reach @" << ToFn.getName() << " [FromFn]\n");
749 if (Result)
750 return true;
751 }
752
753 // TODO: Check assumed nounwind.
754 const auto *ReachabilityAA = A.getAAFor<AAIntraFnReachability>(
755 QueryingAA, IRPosition::function(*FromFn), DepClassTy::OPTIONAL);
756 auto ReturnInstCB = [&](Instruction &Ret) {
757 bool Result = !ReachabilityAA || ReachabilityAA->isAssumedReachable(
758 A, *CurFromI, Ret, ExclusionSet);
759 LLVM_DEBUG(dbgs() << "[AA][Ret] " << *CurFromI << " "
760 << (Result ? "can potentially " : "cannot ") << "reach "
761 << Ret << " [Intra]\n");
762 return !Result;
763 };
764
765 // Check if we can reach returns.
766 bool UsedAssumedInformation = false;
767 if (A.checkForAllInstructions(ReturnInstCB, FromFn, &QueryingAA,
768 {Instruction::Ret}, UsedAssumedInformation)) {
769 LLVM_DEBUG(dbgs() << "[AA] No return is reachable, done\n");
770 continue;
771 }
772
773 if (!GoBackwardsCB) {
774 LLVM_DEBUG(dbgs() << "[AA] check @" << ToFn.getName() << " from " << FromI
775 << " is not checked backwards, abort\n");
776 return true;
777 }
778
779 // If we do not go backwards from the FromFn we are done here and so far we
780 // could not find a way to reach ToFn/ToI.
781 if (!GoBackwardsCB(*FromFn))
782 continue;
783
784 LLVM_DEBUG(dbgs() << "Stepping backwards to the call sites of @"
785 << FromFn->getName() << "\n");
786
787 auto CheckCallSite = [&](AbstractCallSite ACS) {
788 CallBase *CB = ACS.getInstruction();
789 if (!CB)
790 return false;
791
792 if (isa<InvokeInst>(CB))
793 return false;
794
796 Worklist.push_back(Inst);
797 return true;
798 };
799
800 Result = !A.checkForAllCallSites(CheckCallSite, *FromFn,
801 /* RequireAllCallSites */ true,
802 &QueryingAA, UsedAssumedInformation);
803 if (Result) {
804 LLVM_DEBUG(dbgs() << "[AA] stepping back to call sites from " << *CurFromI
805 << " in @" << FromFn->getName()
806 << " failed, give up\n");
807 return true;
808 }
809
810 LLVM_DEBUG(dbgs() << "[AA] stepped back to call sites from " << *CurFromI
811 << " in @" << FromFn->getName()
812 << " worklist size is: " << Worklist.size() << "\n");
813 }
814 return false;
815}
816
818 Attributor &A, const Instruction &FromI, const Instruction &ToI,
819 const AbstractAttribute &QueryingAA,
820 const AA::InstExclusionSetTy *ExclusionSet,
821 std::function<bool(const Function &F)> GoBackwardsCB) {
822 const Function *ToFn = ToI.getFunction();
823 return ::isPotentiallyReachable(A, FromI, &ToI, *ToFn, QueryingAA,
824 ExclusionSet, GoBackwardsCB);
825}
826
828 Attributor &A, const Instruction &FromI, const Function &ToFn,
829 const AbstractAttribute &QueryingAA,
830 const AA::InstExclusionSetTy *ExclusionSet,
831 std::function<bool(const Function &F)> GoBackwardsCB) {
832 return ::isPotentiallyReachable(A, FromI, /* ToI */ nullptr, ToFn, QueryingAA,
833 ExclusionSet, GoBackwardsCB);
834}
835
837 const AbstractAttribute &QueryingAA) {
838 if (isa<UndefValue>(Obj))
839 return true;
840 if (isa<AllocaInst>(Obj)) {
841 InformationCache &InfoCache = A.getInfoCache();
842 if (!InfoCache.stackIsAccessibleByOtherThreads()) {
844 dbgs() << "[AA] Object '" << Obj
845 << "' is thread local; stack objects are thread local.\n");
846 return true;
847 }
848 bool IsKnownNoCapture;
849 bool IsAssumedNoCapture = AA::hasAssumedIRAttr<Attribute::NoCapture>(
850 A, &QueryingAA, IRPosition::value(Obj), DepClassTy::OPTIONAL,
851 IsKnownNoCapture);
852 LLVM_DEBUG(dbgs() << "[AA] Object '" << Obj << "' is "
853 << (IsAssumedNoCapture ? "" : "not") << " thread local; "
854 << (IsAssumedNoCapture ? "non-" : "")
855 << "captured stack object.\n");
856 return IsAssumedNoCapture;
857 }
858 if (auto *GV = dyn_cast<GlobalVariable>(&Obj)) {
859 if (GV->isConstant()) {
860 LLVM_DEBUG(dbgs() << "[AA] Object '" << Obj
861 << "' is thread local; constant global\n");
862 return true;
863 }
864 if (GV->isThreadLocal()) {
865 LLVM_DEBUG(dbgs() << "[AA] Object '" << Obj
866 << "' is thread local; thread local global\n");
867 return true;
868 }
869 }
870
871 if (A.getInfoCache().targetIsGPU()) {
872 if (Obj.getType()->getPointerAddressSpace() ==
873 (int)AA::GPUAddressSpace::Local) {
874 LLVM_DEBUG(dbgs() << "[AA] Object '" << Obj
875 << "' is thread local; GPU local memory\n");
876 return true;
877 }
878 if (Obj.getType()->getPointerAddressSpace() ==
879 (int)AA::GPUAddressSpace::Constant) {
880 LLVM_DEBUG(dbgs() << "[AA] Object '" << Obj
881 << "' is thread local; GPU constant memory\n");
882 return true;
883 }
884 }
885
886 LLVM_DEBUG(dbgs() << "[AA] Object '" << Obj << "' is not thread local\n");
887 return false;
888}
889
891 const AbstractAttribute &QueryingAA) {
892 if (!I.mayHaveSideEffects() && !I.mayReadFromMemory())
893 return false;
894
896
897 auto AddLocationPtr = [&](std::optional<MemoryLocation> Loc) {
898 if (!Loc || !Loc->Ptr) {
900 dbgs() << "[AA] Access to unknown location; -> requires barriers\n");
901 return false;
902 }
903 Ptrs.insert(Loc->Ptr);
904 return true;
905 };
906
907 if (const MemIntrinsic *MI = dyn_cast<MemIntrinsic>(&I)) {
908 if (!AddLocationPtr(MemoryLocation::getForDest(MI)))
909 return true;
910 if (const MemTransferInst *MTI = dyn_cast<MemTransferInst>(&I))
911 if (!AddLocationPtr(MemoryLocation::getForSource(MTI)))
912 return true;
913 } else if (!AddLocationPtr(MemoryLocation::getOrNone(&I)))
914 return true;
915
916 return isPotentiallyAffectedByBarrier(A, Ptrs.getArrayRef(), QueryingAA, &I);
917}
918
921 const AbstractAttribute &QueryingAA,
922 const Instruction *CtxI) {
923 for (const Value *Ptr : Ptrs) {
924 if (!Ptr) {
925 LLVM_DEBUG(dbgs() << "[AA] nullptr; -> requires barriers\n");
926 return true;
927 }
928
929 auto Pred = [&](Value &Obj) {
930 if (AA::isAssumedThreadLocalObject(A, Obj, QueryingAA))
931 return true;
932 LLVM_DEBUG(dbgs() << "[AA] Access to '" << Obj << "' via '" << *Ptr
933 << "'; -> requires barrier\n");
934 return false;
935 };
936
937 const auto *UnderlyingObjsAA = A.getAAFor<AAUnderlyingObjects>(
938 QueryingAA, IRPosition::value(*Ptr), DepClassTy::OPTIONAL);
939 if (!UnderlyingObjsAA || !UnderlyingObjsAA->forallUnderlyingObjects(Pred))
940 return true;
941 }
942 return false;
943}
944
945/// Return true if \p New is equal or worse than \p Old.
946static bool isEqualOrWorse(const Attribute &New, const Attribute &Old) {
947 if (!Old.isIntAttribute())
948 return true;
949
950 return Old.getValueAsInt() >= New.getValueAsInt();
951}
952
953/// Return true if the information provided by \p Attr was added to the
954/// attribute set \p AttrSet. This is only the case if it was not already
955/// present in \p AttrSet.
956static bool addIfNotExistent(LLVMContext &Ctx, const Attribute &Attr,
957 AttributeSet AttrSet, bool ForceReplace,
958 AttrBuilder &AB) {
959
960 if (Attr.isEnumAttribute()) {
962 if (AttrSet.hasAttribute(Kind))
963 return false;
964 AB.addAttribute(Kind);
965 return true;
966 }
967 if (Attr.isStringAttribute()) {
968 StringRef Kind = Attr.getKindAsString();
969 if (AttrSet.hasAttribute(Kind)) {
970 if (!ForceReplace)
971 return false;
972 }
973 AB.addAttribute(Kind, Attr.getValueAsString());
974 return true;
975 }
976 if (Attr.isIntAttribute()) {
978 if (!ForceReplace && Kind == Attribute::Memory) {
979 MemoryEffects ME = Attr.getMemoryEffects() & AttrSet.getMemoryEffects();
980 if (ME == AttrSet.getMemoryEffects())
981 return false;
982 AB.addMemoryAttr(ME);
983 return true;
984 }
985 if (AttrSet.hasAttribute(Kind)) {
986 if (!ForceReplace && isEqualOrWorse(Attr, AttrSet.getAttribute(Kind)))
987 return false;
988 }
989 AB.addAttribute(Attr);
990 return true;
991 }
992
993 llvm_unreachable("Expected enum or string attribute!");
994}
995
998 return cast<Argument>(&getAnchorValue());
999
1000 // Not an Argument and no argument number means this is not a call site
1001 // argument, thus we cannot find a callback argument to return.
1002 int ArgNo = getCallSiteArgNo();
1003 if (ArgNo < 0)
1004 return nullptr;
1005
1006 // Use abstract call sites to make the connection between the call site
1007 // values and the ones in callbacks. If a callback was found that makes use
1008 // of the underlying call site operand, we want the corresponding callback
1009 // callee argument and not the direct callee argument.
1010 std::optional<Argument *> CBCandidateArg;
1011 SmallVector<const Use *, 4> CallbackUses;
1012 const auto &CB = cast<CallBase>(getAnchorValue());
1013 AbstractCallSite::getCallbackUses(CB, CallbackUses);
1014 for (const Use *U : CallbackUses) {
1015 AbstractCallSite ACS(U);
1016 assert(ACS && ACS.isCallbackCall());
1017 if (!ACS.getCalledFunction())
1018 continue;
1019
1020 for (unsigned u = 0, e = ACS.getNumArgOperands(); u < e; u++) {
1021
1022 // Test if the underlying call site operand is argument number u of the
1023 // callback callee.
1024 if (ACS.getCallArgOperandNo(u) != ArgNo)
1025 continue;
1026
1027 assert(ACS.getCalledFunction()->arg_size() > u &&
1028 "ACS mapped into var-args arguments!");
1029 if (CBCandidateArg) {
1030 CBCandidateArg = nullptr;
1031 break;
1032 }
1033 CBCandidateArg = ACS.getCalledFunction()->getArg(u);
1034 }
1035 }
1036
1037 // If we found a unique callback candidate argument, return it.
1038 if (CBCandidateArg && *CBCandidateArg)
1039 return *CBCandidateArg;
1040
1041 // If no callbacks were found, or none used the underlying call site operand
1042 // exclusively, use the direct callee argument if available.
1043 auto *Callee = dyn_cast_if_present<Function>(CB.getCalledOperand());
1044 if (Callee && Callee->arg_size() > unsigned(ArgNo))
1045 return Callee->getArg(ArgNo);
1046
1047 return nullptr;
1048}
1049
1052 if (getState().isAtFixpoint())
1053 return HasChanged;
1054
1055 LLVM_DEBUG(dbgs() << "[Attributor] Update: " << *this << "\n");
1056
1057 HasChanged = updateImpl(A);
1058
1059 LLVM_DEBUG(dbgs() << "[Attributor] Update " << HasChanged << " " << *this
1060 << "\n");
1061
1062 return HasChanged;
1063}
1064
1066 InformationCache &InfoCache,
1067 AttributorConfig Configuration)
1068 : Allocator(InfoCache.Allocator), Functions(Functions),
1069 InfoCache(InfoCache), Configuration(Configuration) {
1070 if (!isClosedWorldModule())
1071 return;
1072 for (Function *Fn : Functions)
1073 if (Fn->hasAddressTaken(/*PutOffender=*/nullptr,
1074 /*IgnoreCallbackUses=*/false,
1075 /*IgnoreAssumeLikeCalls=*/true,
1076 /*IgnoreLLVMUsed=*/true,
1077 /*IgnoreARCAttachedCall=*/false,
1078 /*IgnoreCastedDirectCall=*/true))
1079 InfoCache.IndirectlyCallableFunctions.push_back(Fn);
1080}
1081
1086 "Did expect a valid position!");
1089 if (!Explorer)
1090 return false;
1091
1092 Value &AssociatedValue = IRP.getAssociatedValue();
1093
1094 const Assume2KnowledgeMap &A2K =
1095 getInfoCache().getKnowledgeMap().lookup({&AssociatedValue, AK});
1096
1097 // Check if we found any potential assume use, if not we don't need to create
1098 // explorer iterators.
1099 if (A2K.empty())
1100 return false;
1101
1102 LLVMContext &Ctx = AssociatedValue.getContext();
1103 unsigned AttrsSize = Attrs.size();
1104 auto EIt = Explorer->begin(IRP.getCtxI()),
1105 EEnd = Explorer->end(IRP.getCtxI());
1106 for (const auto &It : A2K)
1107 if (Explorer->findInContextOf(It.first, EIt, EEnd))
1108 Attrs.push_back(Attribute::get(Ctx, AK, It.second.Max));
1109 return AttrsSize != Attrs.size();
1110}
1111
1112template <typename DescTy>
1114Attributor::updateAttrMap(const IRPosition &IRP, ArrayRef<DescTy> AttrDescs,
1115 function_ref<bool(const DescTy &, AttributeSet,
1117 CB) {
1118 if (AttrDescs.empty())
1120 switch (IRP.getPositionKind()) {
1124 default:
1125 break;
1126 };
1127
1128 AttributeList AL;
1129 Value *AttrListAnchor = IRP.getAttrListAnchor();
1130 auto It = AttrsMap.find(AttrListAnchor);
1131 if (It == AttrsMap.end())
1132 AL = IRP.getAttrList();
1133 else
1134 AL = It->getSecond();
1135
1136 LLVMContext &Ctx = IRP.getAnchorValue().getContext();
1137 auto AttrIdx = IRP.getAttrIdx();
1138 AttributeSet AS = AL.getAttributes(AttrIdx);
1139 AttributeMask AM;
1140 AttrBuilder AB(Ctx);
1141
1143 for (const DescTy &AttrDesc : AttrDescs)
1144 if (CB(AttrDesc, AS, AM, AB))
1145 HasChanged = ChangeStatus::CHANGED;
1146
1147 if (HasChanged == ChangeStatus::UNCHANGED)
1149
1150 AL = AL.removeAttributesAtIndex(Ctx, AttrIdx, AM);
1151 AL = AL.addAttributesAtIndex(Ctx, AttrIdx, AB);
1152 AttrsMap[AttrListAnchor] = AL;
1153 return ChangeStatus::CHANGED;
1154}
1155
1158 bool IgnoreSubsumingPositions,
1159 Attribute::AttrKind ImpliedAttributeKind) {
1160 bool Implied = false;
1161 bool HasAttr = false;
1162 auto HasAttrCB = [&](const Attribute::AttrKind &Kind, AttributeSet AttrSet,
1164 if (AttrSet.hasAttribute(Kind)) {
1165 Implied |= Kind != ImpliedAttributeKind;
1166 HasAttr = true;
1167 }
1168 return false;
1169 };
1170 for (const IRPosition &EquivIRP : SubsumingPositionIterator(IRP)) {
1171 updateAttrMap<Attribute::AttrKind>(EquivIRP, AttrKinds, HasAttrCB);
1172 if (HasAttr)
1173 break;
1174 // The first position returned by the SubsumingPositionIterator is
1175 // always the position itself. If we ignore subsuming positions we
1176 // are done after the first iteration.
1177 if (IgnoreSubsumingPositions)
1178 break;
1179 Implied = true;
1180 }
1181 if (!HasAttr) {
1182 Implied = true;
1184 for (Attribute::AttrKind AK : AttrKinds)
1185 if (getAttrsFromAssumes(IRP, AK, Attrs)) {
1186 HasAttr = true;
1187 break;
1188 }
1189 }
1190
1191 // Check if we should manifest the implied attribute kind at the IRP.
1192 if (ImpliedAttributeKind != Attribute::None && HasAttr && Implied)
1194 ImpliedAttributeKind)});
1195 return HasAttr;
1196}
1197
1201 bool IgnoreSubsumingPositions) {
1202 auto CollectAttrCB = [&](const Attribute::AttrKind &Kind,
1203 AttributeSet AttrSet, AttributeMask &,
1204 AttrBuilder &) {
1205 if (AttrSet.hasAttribute(Kind))
1206 Attrs.push_back(AttrSet.getAttribute(Kind));
1207 return false;
1208 };
1209 for (const IRPosition &EquivIRP : SubsumingPositionIterator(IRP)) {
1210 updateAttrMap<Attribute::AttrKind>(EquivIRP, AttrKinds, CollectAttrCB);
1211 // The first position returned by the SubsumingPositionIterator is
1212 // always the position itself. If we ignore subsuming positions we
1213 // are done after the first iteration.
1214 if (IgnoreSubsumingPositions)
1215 break;
1216 }
1217 for (Attribute::AttrKind AK : AttrKinds)
1218 getAttrsFromAssumes(IRP, AK, Attrs);
1219}
1220
1223 auto RemoveAttrCB = [&](const Attribute::AttrKind &Kind, AttributeSet AttrSet,
1224 AttributeMask &AM, AttrBuilder &) {
1225 if (!AttrSet.hasAttribute(Kind))
1226 return false;
1227 AM.addAttribute(Kind);
1228 return true;
1229 };
1230 return updateAttrMap<Attribute::AttrKind>(IRP, AttrKinds, RemoveAttrCB);
1231}
1232
1234 ArrayRef<StringRef> Attrs) {
1235 auto RemoveAttrCB = [&](StringRef Attr, AttributeSet AttrSet,
1236 AttributeMask &AM, AttrBuilder &) -> bool {
1237 if (!AttrSet.hasAttribute(Attr))
1238 return false;
1239 AM.addAttribute(Attr);
1240 return true;
1241 };
1242
1243 return updateAttrMap<StringRef>(IRP, Attrs, RemoveAttrCB);
1244}
1245
1247 ArrayRef<Attribute> Attrs,
1248 bool ForceReplace) {
1249 LLVMContext &Ctx = IRP.getAnchorValue().getContext();
1250 auto AddAttrCB = [&](const Attribute &Attr, AttributeSet AttrSet,
1251 AttributeMask &, AttrBuilder &AB) {
1252 return addIfNotExistent(Ctx, Attr, AttrSet, ForceReplace, AB);
1253 };
1254 return updateAttrMap<Attribute>(IRP, Attrs, AddAttrCB);
1255}
1256
1258const IRPosition
1260
1262 IRPositions.emplace_back(IRP);
1263
1264 // Helper to determine if operand bundles on a call site are benign or
1265 // potentially problematic. We handle only llvm.assume for now.
1266 auto CanIgnoreOperandBundles = [](const CallBase &CB) {
1267 return (isa<IntrinsicInst>(CB) &&
1268 cast<IntrinsicInst>(CB).getIntrinsicID() == Intrinsic ::assume);
1269 };
1270
1271 const auto *CB = dyn_cast<CallBase>(&IRP.getAnchorValue());
1272 switch (IRP.getPositionKind()) {
1276 return;
1279 IRPositions.emplace_back(IRPosition::function(*IRP.getAnchorScope()));
1280 return;
1282 assert(CB && "Expected call site!");
1283 // TODO: We need to look at the operand bundles similar to the redirection
1284 // in CallBase.
1285 if (!CB->hasOperandBundles() || CanIgnoreOperandBundles(*CB))
1286 if (auto *Callee = dyn_cast_if_present<Function>(CB->getCalledOperand()))
1287 IRPositions.emplace_back(IRPosition::function(*Callee));
1288 return;
1290 assert(CB && "Expected call site!");
1291 // TODO: We need to look at the operand bundles similar to the redirection
1292 // in CallBase.
1293 if (!CB->hasOperandBundles() || CanIgnoreOperandBundles(*CB)) {
1294 if (auto *Callee =
1295 dyn_cast_if_present<Function>(CB->getCalledOperand())) {
1296 IRPositions.emplace_back(IRPosition::returned(*Callee));
1297 IRPositions.emplace_back(IRPosition::function(*Callee));
1298 for (const Argument &Arg : Callee->args())
1299 if (Arg.hasReturnedAttr()) {
1300 IRPositions.emplace_back(
1301 IRPosition::callsite_argument(*CB, Arg.getArgNo()));
1302 IRPositions.emplace_back(
1303 IRPosition::value(*CB->getArgOperand(Arg.getArgNo())));
1304 IRPositions.emplace_back(IRPosition::argument(Arg));
1305 }
1306 }
1307 }
1308 IRPositions.emplace_back(IRPosition::callsite_function(*CB));
1309 return;
1311 assert(CB && "Expected call site!");
1312 // TODO: We need to look at the operand bundles similar to the redirection
1313 // in CallBase.
1314 if (!CB->hasOperandBundles() || CanIgnoreOperandBundles(*CB)) {
1315 auto *Callee = dyn_cast_if_present<Function>(CB->getCalledOperand());
1316 if (Callee) {
1317 if (Argument *Arg = IRP.getAssociatedArgument())
1318 IRPositions.emplace_back(IRPosition::argument(*Arg));
1319 IRPositions.emplace_back(IRPosition::function(*Callee));
1320 }
1321 }
1322 IRPositions.emplace_back(IRPosition::value(IRP.getAssociatedValue()));
1323 return;
1324 }
1325 }
1326}
1327
1328void IRPosition::verify() {
1329#ifdef EXPENSIVE_CHECKS
1330 switch (getPositionKind()) {
1331 case IRP_INVALID:
1332 assert((CBContext == nullptr) &&
1333 "Invalid position must not have CallBaseContext!");
1334 assert(!Enc.getOpaqueValue() &&
1335 "Expected a nullptr for an invalid position!");
1336 return;
1337 case IRP_FLOAT:
1338 assert((!isa<Argument>(&getAssociatedValue())) &&
1339 "Expected specialized kind for argument values!");
1340 return;
1341 case IRP_RETURNED:
1342 assert(isa<Function>(getAsValuePtr()) &&
1343 "Expected function for a 'returned' position!");
1344 assert(getAsValuePtr() == &getAssociatedValue() &&
1345 "Associated value mismatch!");
1346 return;
1348 assert((CBContext == nullptr) &&
1349 "'call site returned' position must not have CallBaseContext!");
1350 assert((isa<CallBase>(getAsValuePtr())) &&
1351 "Expected call base for 'call site returned' position!");
1352 assert(getAsValuePtr() == &getAssociatedValue() &&
1353 "Associated value mismatch!");
1354 return;
1355 case IRP_CALL_SITE:
1356 assert((CBContext == nullptr) &&
1357 "'call site function' position must not have CallBaseContext!");
1358 assert((isa<CallBase>(getAsValuePtr())) &&
1359 "Expected call base for 'call site function' position!");
1360 assert(getAsValuePtr() == &getAssociatedValue() &&
1361 "Associated value mismatch!");
1362 return;
1363 case IRP_FUNCTION:
1364 assert(isa<Function>(getAsValuePtr()) &&
1365 "Expected function for a 'function' position!");
1366 assert(getAsValuePtr() == &getAssociatedValue() &&
1367 "Associated value mismatch!");
1368 return;
1369 case IRP_ARGUMENT:
1370 assert(isa<Argument>(getAsValuePtr()) &&
1371 "Expected argument for a 'argument' position!");
1372 assert(getAsValuePtr() == &getAssociatedValue() &&
1373 "Associated value mismatch!");
1374 return;
1376 assert((CBContext == nullptr) &&
1377 "'call site argument' position must not have CallBaseContext!");
1378 Use *U = getAsUsePtr();
1379 (void)U; // Silence unused variable warning.
1380 assert(U && "Expected use for a 'call site argument' position!");
1381 assert(isa<CallBase>(U->getUser()) &&
1382 "Expected call base user for a 'call site argument' position!");
1383 assert(cast<CallBase>(U->getUser())->isArgOperand(U) &&
1384 "Expected call base argument operand for a 'call site argument' "
1385 "position");
1386 assert(cast<CallBase>(U->getUser())->getArgOperandNo(U) ==
1387 unsigned(getCallSiteArgNo()) &&
1388 "Argument number mismatch!");
1389 assert(U->get() == &getAssociatedValue() && "Associated value mismatch!");
1390 return;
1391 }
1392 }
1393#endif
1394}
1395
1396std::optional<Constant *>
1398 const AbstractAttribute &AA,
1399 bool &UsedAssumedInformation) {
1400 // First check all callbacks provided by outside AAs. If any of them returns
1401 // a non-null value that is different from the associated value, or
1402 // std::nullopt, we assume it's simplified.
1403 for (auto &CB : SimplificationCallbacks.lookup(IRP)) {
1404 std::optional<Value *> SimplifiedV = CB(IRP, &AA, UsedAssumedInformation);
1405 if (!SimplifiedV)
1406 return std::nullopt;
1407 if (isa_and_nonnull<Constant>(*SimplifiedV))
1408 return cast<Constant>(*SimplifiedV);
1409 return nullptr;
1410 }
1411 if (auto *C = dyn_cast<Constant>(&IRP.getAssociatedValue()))
1412 return C;
1414 if (getAssumedSimplifiedValues(IRP, &AA, Values,
1416 UsedAssumedInformation)) {
1417 if (Values.empty())
1418 return std::nullopt;
1419 if (auto *C = dyn_cast_or_null<Constant>(
1420 AAPotentialValues::getSingleValue(*this, AA, IRP, Values)))
1421 return C;
1422 }
1423 return nullptr;
1424}
1425
1427 const IRPosition &IRP, const AbstractAttribute *AA,
1428 bool &UsedAssumedInformation, AA::ValueScope S) {
1429 // First check all callbacks provided by outside AAs. If any of them returns
1430 // a non-null value that is different from the associated value, or
1431 // std::nullopt, we assume it's simplified.
1432 for (auto &CB : SimplificationCallbacks.lookup(IRP))
1433 return CB(IRP, AA, UsedAssumedInformation);
1434
1436 if (!getAssumedSimplifiedValues(IRP, AA, Values, S, UsedAssumedInformation))
1437 return &IRP.getAssociatedValue();
1438 if (Values.empty())
1439 return std::nullopt;
1440 if (AA)
1441 if (Value *V = AAPotentialValues::getSingleValue(*this, *AA, IRP, Values))
1442 return V;
1445 return nullptr;
1446 return &IRP.getAssociatedValue();
1447}
1448
1450 const IRPosition &InitialIRP, const AbstractAttribute *AA,
1452 bool &UsedAssumedInformation, bool RecurseForSelectAndPHI) {
1455 Worklist.push_back(InitialIRP);
1456 while (!Worklist.empty()) {
1457 const IRPosition &IRP = Worklist.pop_back_val();
1458
1459 // First check all callbacks provided by outside AAs. If any of them returns
1460 // a non-null value that is different from the associated value, or
1461 // std::nullopt, we assume it's simplified.
1462 int NV = Values.size();
1463 const auto &SimplificationCBs = SimplificationCallbacks.lookup(IRP);
1464 for (const auto &CB : SimplificationCBs) {
1465 std::optional<Value *> CBResult = CB(IRP, AA, UsedAssumedInformation);
1466 if (!CBResult.has_value())
1467 continue;
1468 Value *V = *CBResult;
1469 if (!V)
1470 return false;
1473 Values.push_back(AA::ValueAndContext{*V, nullptr});
1474 else
1475 return false;
1476 }
1477 if (SimplificationCBs.empty()) {
1478 // If no high-level/outside simplification occurred, use
1479 // AAPotentialValues.
1480 const auto *PotentialValuesAA =
1481 getOrCreateAAFor<AAPotentialValues>(IRP, AA, DepClassTy::OPTIONAL);
1482 if (PotentialValuesAA && PotentialValuesAA->getAssumedSimplifiedValues(*this, Values, S)) {
1483 UsedAssumedInformation |= !PotentialValuesAA->isAtFixpoint();
1484 } else if (IRP.getPositionKind() != IRPosition::IRP_RETURNED) {
1485 Values.push_back({IRP.getAssociatedValue(), IRP.getCtxI()});
1486 } else {
1487 // TODO: We could visit all returns and add the operands.
1488 return false;
1489 }
1490 }
1491
1492 if (!RecurseForSelectAndPHI)
1493 break;
1494
1495 for (int I = NV, E = Values.size(); I < E; ++I) {
1496 Value *V = Values[I].getValue();
1497 if (!isa<PHINode>(V) && !isa<SelectInst>(V))
1498 continue;
1499 if (!Seen.insert(V).second)
1500 continue;
1501 // Move the last element to this slot.
1502 Values[I] = Values[E - 1];
1503 // Eliminate the last slot, adjust the indices.
1504 Values.pop_back();
1505 --E;
1506 --I;
1507 // Add a new value (select or phi) to the worklist.
1508 Worklist.push_back(IRPosition::value(*V));
1509 }
1510 }
1511 return true;
1512}
1513
1515 std::optional<Value *> V, CallBase &CB, const AbstractAttribute &AA,
1516 bool &UsedAssumedInformation) {
1517 if (!V)
1518 return V;
1519 if (*V == nullptr || isa<Constant>(*V))
1520 return V;
1521 if (auto *Arg = dyn_cast<Argument>(*V))
1522 if (CB.getCalledOperand() == Arg->getParent() &&
1523 CB.arg_size() > Arg->getArgNo())
1524 if (!Arg->hasPointeeInMemoryValueAttr())
1525 return getAssumedSimplified(
1526 IRPosition::callsite_argument(CB, Arg->getArgNo()), AA,
1527 UsedAssumedInformation, AA::Intraprocedural);
1528 return nullptr;
1529}
1530
1532 // The abstract attributes are allocated via the BumpPtrAllocator Allocator,
1533 // thus we cannot delete them. We can, and want to, destruct them though.
1534 for (auto &It : AAMap) {
1535 AbstractAttribute *AA = It.getSecond();
1536 AA->~AbstractAttribute();
1537 }
1538}
1539
1541 const AAIsDead *FnLivenessAA,
1542 bool &UsedAssumedInformation,
1543 bool CheckBBLivenessOnly, DepClassTy DepClass) {
1544 if (!Configuration.UseLiveness)
1545 return false;
1546 const IRPosition &IRP = AA.getIRPosition();
1547 if (!Functions.count(IRP.getAnchorScope()))
1548 return false;
1549 return isAssumedDead(IRP, &AA, FnLivenessAA, UsedAssumedInformation,
1550 CheckBBLivenessOnly, DepClass);
1551}
1552
1554 const AbstractAttribute *QueryingAA,
1555 const AAIsDead *FnLivenessAA,
1556 bool &UsedAssumedInformation,
1557 bool CheckBBLivenessOnly, DepClassTy DepClass) {
1558 if (!Configuration.UseLiveness)
1559 return false;
1560 Instruction *UserI = dyn_cast<Instruction>(U.getUser());
1561 if (!UserI)
1562 return isAssumedDead(IRPosition::value(*U.get()), QueryingAA, FnLivenessAA,
1563 UsedAssumedInformation, CheckBBLivenessOnly, DepClass);
1564
1565 if (auto *CB = dyn_cast<CallBase>(UserI)) {
1566 // For call site argument uses we can check if the argument is
1567 // unused/dead.
1568 if (CB->isArgOperand(&U)) {
1569 const IRPosition &CSArgPos =
1570 IRPosition::callsite_argument(*CB, CB->getArgOperandNo(&U));
1571 return isAssumedDead(CSArgPos, QueryingAA, FnLivenessAA,
1572 UsedAssumedInformation, CheckBBLivenessOnly,
1573 DepClass);
1574 }
1575 } else if (ReturnInst *RI = dyn_cast<ReturnInst>(UserI)) {
1576 const IRPosition &RetPos = IRPosition::returned(*RI->getFunction());
1577 return isAssumedDead(RetPos, QueryingAA, FnLivenessAA,
1578 UsedAssumedInformation, CheckBBLivenessOnly, DepClass);
1579 } else if (PHINode *PHI = dyn_cast<PHINode>(UserI)) {
1580 BasicBlock *IncomingBB = PHI->getIncomingBlock(U);
1581 return isAssumedDead(*IncomingBB->getTerminator(), QueryingAA, FnLivenessAA,
1582 UsedAssumedInformation, CheckBBLivenessOnly, DepClass);
1583 } else if (StoreInst *SI = dyn_cast<StoreInst>(UserI)) {
1584 if (!CheckBBLivenessOnly && SI->getPointerOperand() != U.get()) {
1585 const IRPosition IRP = IRPosition::inst(*SI);
1586 const AAIsDead *IsDeadAA =
1587 getOrCreateAAFor<AAIsDead>(IRP, QueryingAA, DepClassTy::NONE);
1588 if (IsDeadAA && IsDeadAA->isRemovableStore()) {
1589 if (QueryingAA)
1590 recordDependence(*IsDeadAA, *QueryingAA, DepClass);
1591 if (!IsDeadAA->isKnown(AAIsDead::IS_REMOVABLE))
1592 UsedAssumedInformation = true;
1593 return true;
1594 }
1595 }
1596 }
1597
1598 return isAssumedDead(IRPosition::inst(*UserI), QueryingAA, FnLivenessAA,
1599 UsedAssumedInformation, CheckBBLivenessOnly, DepClass);
1600}
1601
1603 const AbstractAttribute *QueryingAA,
1604 const AAIsDead *FnLivenessAA,
1605 bool &UsedAssumedInformation,
1606 bool CheckBBLivenessOnly, DepClassTy DepClass,
1607 bool CheckForDeadStore) {
1608 if (!Configuration.UseLiveness)
1609 return false;
1610 const IRPosition::CallBaseContext *CBCtx =
1611 QueryingAA ? QueryingAA->getCallBaseContext() : nullptr;
1612
1613 if (ManifestAddedBlocks.contains(I.getParent()))
1614 return false;
1615
1616 const Function &F = *I.getFunction();
1617 if (!FnLivenessAA || FnLivenessAA->getAnchorScope() != &F)
1618 FnLivenessAA = getOrCreateAAFor<AAIsDead>(IRPosition::function(F, CBCtx),
1619 QueryingAA, DepClassTy::NONE);
1620
1621 // Don't use recursive reasoning.
1622 if (!FnLivenessAA || QueryingAA == FnLivenessAA)
1623 return false;
1624
1625 // If we have a context instruction and a liveness AA we use it.
1626 if (CheckBBLivenessOnly ? FnLivenessAA->isAssumedDead(I.getParent())
1627 : FnLivenessAA->isAssumedDead(&I)) {
1628 if (QueryingAA)
1629 recordDependence(*FnLivenessAA, *QueryingAA, DepClass);
1630 if (!FnLivenessAA->isKnownDead(&I))
1631 UsedAssumedInformation = true;
1632 return true;
1633 }
1634
1635 if (CheckBBLivenessOnly)
1636 return false;
1637
1638 const IRPosition IRP = IRPosition::inst(I, CBCtx);
1639 const AAIsDead *IsDeadAA =
1640 getOrCreateAAFor<AAIsDead>(IRP, QueryingAA, DepClassTy::NONE);
1641
1642 // Don't use recursive reasoning.
1643 if (!IsDeadAA || QueryingAA == IsDeadAA)
1644 return false;
1645
1646 if (IsDeadAA->isAssumedDead()) {
1647 if (QueryingAA)
1648 recordDependence(*IsDeadAA, *QueryingAA, DepClass);
1649 if (!IsDeadAA->isKnownDead())
1650 UsedAssumedInformation = true;
1651 return true;
1652 }
1653
1654 if (CheckForDeadStore && isa<StoreInst>(I) && IsDeadAA->isRemovableStore()) {
1655 if (QueryingAA)
1656 recordDependence(*IsDeadAA, *QueryingAA, DepClass);
1657 if (!IsDeadAA->isKnownDead())
1658 UsedAssumedInformation = true;
1659 return true;
1660 }
1661
1662 return false;
1663}
1664
1666 const AbstractAttribute *QueryingAA,
1667 const AAIsDead *FnLivenessAA,
1668 bool &UsedAssumedInformation,
1669 bool CheckBBLivenessOnly, DepClassTy DepClass) {
1670 if (!Configuration.UseLiveness)
1671 return false;
1672 // Don't check liveness for constants, e.g. functions, used as (floating)
1673 // values since the context instruction and such is here meaningless.
1675 isa<Constant>(IRP.getAssociatedValue())) {
1676 return false;
1677 }
1678
1679 Instruction *CtxI = IRP.getCtxI();
1680 if (CtxI &&
1681 isAssumedDead(*CtxI, QueryingAA, FnLivenessAA, UsedAssumedInformation,
1682 /* CheckBBLivenessOnly */ true,
1683 CheckBBLivenessOnly ? DepClass : DepClassTy::OPTIONAL))
1684 return true;
1685
1686 if (CheckBBLivenessOnly)
1687 return false;
1688
1689 // If we haven't succeeded we query the specific liveness info for the IRP.
1690 const AAIsDead *IsDeadAA;
1692 IsDeadAA = getOrCreateAAFor<AAIsDead>(
1694 QueryingAA, DepClassTy::NONE);
1695 else
1696 IsDeadAA = getOrCreateAAFor<AAIsDead>(IRP, QueryingAA, DepClassTy::NONE);
1697
1698 // Don't use recursive reasoning.
1699 if (!IsDeadAA || QueryingAA == IsDeadAA)
1700 return false;
1701
1702 if (IsDeadAA->isAssumedDead()) {
1703 if (QueryingAA)
1704 recordDependence(*IsDeadAA, *QueryingAA, DepClass);
1705 if (!IsDeadAA->isKnownDead())
1706 UsedAssumedInformation = true;
1707 return true;
1708 }
1709
1710 return false;
1711}
1712
1714 const AbstractAttribute *QueryingAA,
1715 const AAIsDead *FnLivenessAA,
1716 DepClassTy DepClass) {
1717 if (!Configuration.UseLiveness)
1718 return false;
1719 const Function &F = *BB.getParent();
1720 if (!FnLivenessAA || FnLivenessAA->getAnchorScope() != &F)
1721 FnLivenessAA = getOrCreateAAFor<AAIsDead>(IRPosition::function(F),
1722 QueryingAA, DepClassTy::NONE);
1723
1724 // Don't use recursive reasoning.
1725 if (!FnLivenessAA || QueryingAA == FnLivenessAA)
1726 return false;
1727
1728 if (FnLivenessAA->isAssumedDead(&BB)) {
1729 if (QueryingAA)
1730 recordDependence(*FnLivenessAA, *QueryingAA, DepClass);
1731 return true;
1732 }
1733
1734 return false;
1735}
1736
1739 const AbstractAttribute &QueryingAA, const CallBase &CB) {
1740 if (const Function *Callee = dyn_cast<Function>(CB.getCalledOperand()))
1741 return Pred(Callee);
1742
1743 const auto *CallEdgesAA = getAAFor<AACallEdges>(
1745 if (!CallEdgesAA || CallEdgesAA->hasUnknownCallee())
1746 return false;
1747
1748 const auto &Callees = CallEdgesAA->getOptimisticEdges();
1749 return Pred(Callees.getArrayRef());
1750}
1751
1752bool canMarkAsVisited(const User *Usr) {
1753 return isa<PHINode>(Usr) || !isa<Instruction>(Usr);
1754}
1755
1757 function_ref<bool(const Use &, bool &)> Pred,
1758 const AbstractAttribute &QueryingAA, const Value &V,
1759 bool CheckBBLivenessOnly, DepClassTy LivenessDepClass,
1760 bool IgnoreDroppableUses,
1761 function_ref<bool(const Use &OldU, const Use &NewU)> EquivalentUseCB) {
1762
1763 // Check virtual uses first.
1764 for (VirtualUseCallbackTy &CB : VirtualUseCallbacks.lookup(&V))
1765 if (!CB(*this, &QueryingAA))
1766 return false;
1767
1768 // Check the trivial case first as it catches void values.
1769 if (V.use_empty())
1770 return true;
1771
1772 const IRPosition &IRP = QueryingAA.getIRPosition();
1775
1776 auto AddUsers = [&](const Value &V, const Use *OldUse) {
1777 for (const Use &UU : V.uses()) {
1778 if (OldUse && EquivalentUseCB && !EquivalentUseCB(*OldUse, UU)) {
1779 LLVM_DEBUG(dbgs() << "[Attributor] Potential copy was "
1780 "rejected by the equivalence call back: "
1781 << *UU << "!\n");
1782 return false;
1783 }
1784
1785 Worklist.push_back(&UU);
1786 }
1787 return true;
1788 };
1789
1790 AddUsers(V, /* OldUse */ nullptr);
1791
1792 LLVM_DEBUG(dbgs() << "[Attributor] Got " << Worklist.size()
1793 << " initial uses to check\n");
1794
1795 const Function *ScopeFn = IRP.getAnchorScope();
1796 const auto *LivenessAA =
1797 ScopeFn ? getAAFor<AAIsDead>(QueryingAA, IRPosition::function(*ScopeFn),
1799 : nullptr;
1800
1801 while (!Worklist.empty()) {
1802 const Use *U = Worklist.pop_back_val();
1803 if (canMarkAsVisited(U->getUser()) && !Visited.insert(U).second)
1804 continue;
1806 if (auto *Fn = dyn_cast<Function>(U->getUser()))
1807 dbgs() << "[Attributor] Check use: " << **U << " in " << Fn->getName()
1808 << "\n";
1809 else
1810 dbgs() << "[Attributor] Check use: " << **U << " in " << *U->getUser()
1811 << "\n";
1812 });
1813 bool UsedAssumedInformation = false;
1814 if (isAssumedDead(*U, &QueryingAA, LivenessAA, UsedAssumedInformation,
1815 CheckBBLivenessOnly, LivenessDepClass)) {
1817 dbgs() << "[Attributor] Dead use, skip!\n");
1818 continue;
1819 }
1820 if (IgnoreDroppableUses && U->getUser()->isDroppable()) {
1822 dbgs() << "[Attributor] Droppable user, skip!\n");
1823 continue;
1824 }
1825
1826 if (auto *SI = dyn_cast<StoreInst>(U->getUser())) {
1827 if (&SI->getOperandUse(0) == U) {
1828 if (!Visited.insert(U).second)
1829 continue;
1830 SmallSetVector<Value *, 4> PotentialCopies;
1832 *this, *SI, PotentialCopies, QueryingAA, UsedAssumedInformation,
1833 /* OnlyExact */ true)) {
1835 dbgs()
1836 << "[Attributor] Value is stored, continue with "
1837 << PotentialCopies.size()
1838 << " potential copies instead!\n");
1839 for (Value *PotentialCopy : PotentialCopies)
1840 if (!AddUsers(*PotentialCopy, U))
1841 return false;
1842 continue;
1843 }
1844 }
1845 }
1846
1847 bool Follow = false;
1848 if (!Pred(*U, Follow))
1849 return false;
1850 if (!Follow)
1851 continue;
1852
1853 User &Usr = *U->getUser();
1854 AddUsers(Usr, /* OldUse */ nullptr);
1855
1856 auto *RI = dyn_cast<ReturnInst>(&Usr);
1857 if (!RI)
1858 continue;
1859
1860 Function &F = *RI->getFunction();
1861 auto CallSitePred = [&](AbstractCallSite ACS) {
1862 return AddUsers(*ACS.getInstruction(), U);
1863 };
1864 if (!checkForAllCallSites(CallSitePred, F, /* RequireAllCallSites */ true,
1865 &QueryingAA, UsedAssumedInformation)) {
1866 LLVM_DEBUG(dbgs() << "[Attributor] Could not follow return instruction "
1867 "to all call sites: "
1868 << *RI << "\n");
1869 return false;
1870 }
1871 }
1872
1873 return true;
1874}
1875
1877 const AbstractAttribute &QueryingAA,
1878 bool RequireAllCallSites,
1879 bool &UsedAssumedInformation) {
1880 // We can try to determine information from
1881 // the call sites. However, this is only possible all call sites are known,
1882 // hence the function has internal linkage.
1883 const IRPosition &IRP = QueryingAA.getIRPosition();
1884 const Function *AssociatedFunction = IRP.getAssociatedFunction();
1885 if (!AssociatedFunction) {
1886 LLVM_DEBUG(dbgs() << "[Attributor] No function associated with " << IRP
1887 << "\n");
1888 return false;
1889 }
1890
1891 return checkForAllCallSites(Pred, *AssociatedFunction, RequireAllCallSites,
1892 &QueryingAA, UsedAssumedInformation);
1893}
1894
1896 const Function &Fn,
1897 bool RequireAllCallSites,
1898 const AbstractAttribute *QueryingAA,
1899 bool &UsedAssumedInformation,
1900 bool CheckPotentiallyDead) {
1901 if (RequireAllCallSites && !Fn.hasLocalLinkage()) {
1902 LLVM_DEBUG(
1903 dbgs()
1904 << "[Attributor] Function " << Fn.getName()
1905 << " has no internal linkage, hence not all call sites are known\n");
1906 return false;
1907 }
1908 // Check virtual uses first.
1909 for (VirtualUseCallbackTy &CB : VirtualUseCallbacks.lookup(&Fn))
1910 if (!CB(*this, QueryingAA))
1911 return false;
1912
1914 for (unsigned u = 0; u < Uses.size(); ++u) {
1915 const Use &U = *Uses[u];
1917 if (auto *Fn = dyn_cast<Function>(U))
1918 dbgs() << "[Attributor] Check use: " << Fn->getName() << " in "
1919 << *U.getUser() << "\n";
1920 else
1921 dbgs() << "[Attributor] Check use: " << *U << " in " << *U.getUser()
1922 << "\n";
1923 });
1924 if (!CheckPotentiallyDead &&
1925 isAssumedDead(U, QueryingAA, nullptr, UsedAssumedInformation,
1926 /* CheckBBLivenessOnly */ true)) {
1928 dbgs() << "[Attributor] Dead use, skip!\n");
1929 continue;
1930 }
1931 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(U.getUser())) {
1932 if (CE->isCast() && CE->getType()->isPointerTy()) {
1934 dbgs() << "[Attributor] Use, is constant cast expression, add "
1935 << CE->getNumUses() << " uses of that expression instead!\n";
1936 });
1937 for (const Use &CEU : CE->uses())
1938 Uses.push_back(&CEU);
1939 continue;
1940 }
1941 }
1942
1943 AbstractCallSite ACS(&U);
1944 if (!ACS) {
1945 LLVM_DEBUG(dbgs() << "[Attributor] Function " << Fn.getName()
1946 << " has non call site use " << *U.get() << " in "
1947 << *U.getUser() << "\n");
1948 // BlockAddress users are allowed.
1949 if (isa<BlockAddress>(U.getUser()))
1950 continue;
1951 return false;
1952 }
1953
1954 const Use *EffectiveUse =
1955 ACS.isCallbackCall() ? &ACS.getCalleeUseForCallback() : &U;
1956 if (!ACS.isCallee(EffectiveUse)) {
1957 if (!RequireAllCallSites) {
1958 LLVM_DEBUG(dbgs() << "[Attributor] User " << *EffectiveUse->getUser()
1959 << " is not a call of " << Fn.getName()
1960 << ", skip use\n");
1961 continue;
1962 }
1963 LLVM_DEBUG(dbgs() << "[Attributor] User " << *EffectiveUse->getUser()
1964 << " is an invalid use of " << Fn.getName() << "\n");
1965 return false;
1966 }
1967
1968 // Make sure the arguments that can be matched between the call site and the
1969 // callee argee on their type. It is unlikely they do not and it doesn't
1970 // make sense for all attributes to know/care about this.
1971 assert(&Fn == ACS.getCalledFunction() && "Expected known callee");
1972 unsigned MinArgsParams =
1973 std::min(size_t(ACS.getNumArgOperands()), Fn.arg_size());
1974 for (unsigned u = 0; u < MinArgsParams; ++u) {
1975 Value *CSArgOp = ACS.getCallArgOperand(u);
1976 if (CSArgOp && Fn.getArg(u)->getType() != CSArgOp->getType()) {
1977 LLVM_DEBUG(
1978 dbgs() << "[Attributor] Call site / callee argument type mismatch ["
1979 << u << "@" << Fn.getName() << ": "
1980 << *Fn.getArg(u)->getType() << " vs. "
1981 << *ACS.getCallArgOperand(u)->getType() << "\n");
1982 return false;
1983 }
1984 }
1985
1986 if (Pred(ACS))
1987 continue;
1988
1989 LLVM_DEBUG(dbgs() << "[Attributor] Call site callback failed for "
1990 << *ACS.getInstruction() << "\n");
1991 return false;
1992 }
1993
1994 return true;
1995}
1996
1997bool Attributor::shouldPropagateCallBaseContext(const IRPosition &IRP) {
1998 // TODO: Maintain a cache of Values that are
1999 // on the pathway from a Argument to a Instruction that would effect the
2000 // liveness/return state etc.
2002}
2003
2005 const AbstractAttribute &QueryingAA,
2007 bool RecurseForSelectAndPHI) {
2008
2009 const IRPosition &IRP = QueryingAA.getIRPosition();
2010 const Function *AssociatedFunction = IRP.getAssociatedFunction();
2011 if (!AssociatedFunction)
2012 return false;
2013
2014 bool UsedAssumedInformation = false;
2017 IRPosition::returned(*AssociatedFunction), &QueryingAA, Values, S,
2018 UsedAssumedInformation, RecurseForSelectAndPHI))
2019 return false;
2020
2021 return llvm::all_of(Values, [&](const AA::ValueAndContext &VAC) {
2022 return Pred(*VAC.getValue());
2023 });
2024}
2025
2028 function_ref<bool(Instruction &)> Pred, const AbstractAttribute *QueryingAA,
2029 const AAIsDead *LivenessAA, ArrayRef<unsigned> Opcodes,
2030 bool &UsedAssumedInformation, bool CheckBBLivenessOnly = false,
2031 bool CheckPotentiallyDead = false) {
2032 for (unsigned Opcode : Opcodes) {
2033 // Check if we have instructions with this opcode at all first.
2034 auto *Insts = OpcodeInstMap.lookup(Opcode);
2035 if (!Insts)
2036 continue;
2037
2038 for (Instruction *I : *Insts) {
2039 // Skip dead instructions.
2040 if (A && !CheckPotentiallyDead &&
2041 A->isAssumedDead(IRPosition::inst(*I), QueryingAA, LivenessAA,
2042 UsedAssumedInformation, CheckBBLivenessOnly)) {
2044 dbgs() << "[Attributor] Instruction " << *I
2045 << " is potentially dead, skip!\n";);
2046 continue;
2047 }
2048
2049 if (!Pred(*I))
2050 return false;
2051 }
2052 }
2053 return true;
2054}
2055
2057 const Function *Fn,
2058 const AbstractAttribute *QueryingAA,
2059 ArrayRef<unsigned> Opcodes,
2060 bool &UsedAssumedInformation,
2061 bool CheckBBLivenessOnly,
2062 bool CheckPotentiallyDead) {
2063 // Since we need to provide instructions we have to have an exact definition.
2064 if (!Fn || Fn->isDeclaration())
2065 return false;
2066
2067 const IRPosition &QueryIRP = IRPosition::function(*Fn);
2068 const auto *LivenessAA =
2069 CheckPotentiallyDead && QueryingAA
2070 ? (getAAFor<AAIsDead>(*QueryingAA, QueryIRP, DepClassTy::NONE))
2071 : nullptr;
2072
2073 auto &OpcodeInstMap = InfoCache.getOpcodeInstMapForFunction(*Fn);
2074 if (!checkForAllInstructionsImpl(this, OpcodeInstMap, Pred, QueryingAA,
2075 LivenessAA, Opcodes, UsedAssumedInformation,
2076 CheckBBLivenessOnly, CheckPotentiallyDead))
2077 return false;
2078
2079 return true;
2080}
2081
2083 const AbstractAttribute &QueryingAA,
2084 ArrayRef<unsigned> Opcodes,
2085 bool &UsedAssumedInformation,
2086 bool CheckBBLivenessOnly,
2087 bool CheckPotentiallyDead) {
2088 const IRPosition &IRP = QueryingAA.getIRPosition();
2089 const Function *AssociatedFunction = IRP.getAssociatedFunction();
2090 return checkForAllInstructions(Pred, AssociatedFunction, &QueryingAA, Opcodes,
2091 UsedAssumedInformation, CheckBBLivenessOnly,
2092 CheckPotentiallyDead);
2093}
2094
2096 function_ref<bool(Instruction &)> Pred, AbstractAttribute &QueryingAA,
2097 bool &UsedAssumedInformation) {
2098 TimeTraceScope TS("checkForAllReadWriteInstructions");
2099
2100 const Function *AssociatedFunction =
2101 QueryingAA.getIRPosition().getAssociatedFunction();
2102 if (!AssociatedFunction)
2103 return false;
2104
2105 const IRPosition &QueryIRP = IRPosition::function(*AssociatedFunction);
2106 const auto *LivenessAA =
2107 getAAFor<AAIsDead>(QueryingAA, QueryIRP, DepClassTy::NONE);
2108
2109 for (Instruction *I :
2110 InfoCache.getReadOrWriteInstsForFunction(*AssociatedFunction)) {
2111 // Skip dead instructions.
2112 if (isAssumedDead(IRPosition::inst(*I), &QueryingAA, LivenessAA,
2113 UsedAssumedInformation))
2114 continue;
2115
2116 if (!Pred(*I))
2117 return false;
2118 }
2119
2120 return true;
2121}
2122
2123void Attributor::runTillFixpoint() {
2124 TimeTraceScope TimeScope("Attributor::runTillFixpoint");
2125 LLVM_DEBUG(dbgs() << "[Attributor] Identified and initialized "
2126 << DG.SyntheticRoot.Deps.size()
2127 << " abstract attributes.\n");
2128
2129 // Now that all abstract attributes are collected and initialized we start
2130 // the abstract analysis.
2131
2132 unsigned IterationCounter = 1;
2133 unsigned MaxIterations =
2134 Configuration.MaxFixpointIterations.value_or(SetFixpointIterations);
2135
2137 SetVector<AbstractAttribute *> Worklist, InvalidAAs;
2138 Worklist.insert(DG.SyntheticRoot.begin(), DG.SyntheticRoot.end());
2139
2140 do {
2141 // Remember the size to determine new attributes.
2142 size_t NumAAs = DG.SyntheticRoot.Deps.size();
2143 LLVM_DEBUG(dbgs() << "\n\n[Attributor] #Iteration: " << IterationCounter
2144 << ", Worklist size: " << Worklist.size() << "\n");
2145
2146 // For invalid AAs we can fix dependent AAs that have a required dependence,
2147 // thereby folding long dependence chains in a single step without the need
2148 // to run updates.
2149 for (unsigned u = 0; u < InvalidAAs.size(); ++u) {
2150 AbstractAttribute *InvalidAA = InvalidAAs[u];
2151
2152 // Check the dependences to fast track invalidation.
2154 dbgs() << "[Attributor] InvalidAA: " << *InvalidAA
2155 << " has " << InvalidAA->Deps.size()
2156 << " required & optional dependences\n");
2157 for (auto &DepIt : InvalidAA->Deps) {
2158 AbstractAttribute *DepAA = cast<AbstractAttribute>(DepIt.getPointer());
2159 if (DepIt.getInt() == unsigned(DepClassTy::OPTIONAL)) {
2161 dbgs() << " - recompute: " << *DepAA);
2162 Worklist.insert(DepAA);
2163 continue;
2164 }
2166 << " - invalidate: " << *DepAA);
2168 assert(DepAA->getState().isAtFixpoint() && "Expected fixpoint state!");
2169 if (!DepAA->getState().isValidState())
2170 InvalidAAs.insert(DepAA);
2171 else
2172 ChangedAAs.push_back(DepAA);
2173 }
2174 InvalidAA->Deps.clear();
2175 }
2176
2177 // Add all abstract attributes that are potentially dependent on one that
2178 // changed to the work list.
2179 for (AbstractAttribute *ChangedAA : ChangedAAs) {
2180 for (auto &DepIt : ChangedAA->Deps)
2181 Worklist.insert(cast<AbstractAttribute>(DepIt.getPointer()));
2182 ChangedAA->Deps.clear();
2183 }
2184
2185 LLVM_DEBUG(dbgs() << "[Attributor] #Iteration: " << IterationCounter
2186 << ", Worklist+Dependent size: " << Worklist.size()
2187 << "\n");
2188
2189 // Reset the changed and invalid set.
2190 ChangedAAs.clear();
2191 InvalidAAs.clear();
2192
2193 // Update all abstract attribute in the work list and record the ones that
2194 // changed.
2195 for (AbstractAttribute *AA : Worklist) {
2196 const auto &AAState = AA->getState();
2197 if (!AAState.isAtFixpoint())
2198 if (updateAA(*AA) == ChangeStatus::CHANGED)
2199 ChangedAAs.push_back(AA);
2200
2201 // Use the InvalidAAs vector to propagate invalid states fast transitively
2202 // without requiring updates.
2203 if (!AAState.isValidState())
2204 InvalidAAs.insert(AA);
2205 }
2206
2207 // Add attributes to the changed set if they have been created in the last
2208 // iteration.
2209 ChangedAAs.append(DG.SyntheticRoot.begin() + NumAAs,
2210 DG.SyntheticRoot.end());
2211
2212 // Reset the work list and repopulate with the changed abstract attributes.
2213 // Note that dependent ones are added above.
2214 Worklist.clear();
2215 Worklist.insert(ChangedAAs.begin(), ChangedAAs.end());
2216 Worklist.insert(QueryAAsAwaitingUpdate.begin(),
2217 QueryAAsAwaitingUpdate.end());
2218 QueryAAsAwaitingUpdate.clear();
2219
2220 } while (!Worklist.empty() && (IterationCounter++ < MaxIterations));
2221
2222 if (IterationCounter > MaxIterations && !Functions.empty()) {
2223 auto Remark = [&](OptimizationRemarkMissed ORM) {
2224 return ORM << "Attributor did not reach a fixpoint after "
2225 << ore::NV("Iterations", MaxIterations) << " iterations.";
2226 };
2227 Function *F = Functions.front();
2228 emitRemark<OptimizationRemarkMissed>(F, "FixedPoint", Remark);
2229 }
2230
2231 LLVM_DEBUG(dbgs() << "\n[Attributor] Fixpoint iteration done after: "
2232 << IterationCounter << "/" << MaxIterations
2233 << " iterations\n");
2234
2235 // Reset abstract arguments not settled in a sound fixpoint by now. This
2236 // happens when we stopped the fixpoint iteration early. Note that only the
2237 // ones marked as "changed" *and* the ones transitively depending on them
2238 // need to be reverted to a pessimistic state. Others might not be in a
2239 // fixpoint state but we can use the optimistic results for them anyway.
2241 for (unsigned u = 0; u < ChangedAAs.size(); u++) {
2242 AbstractAttribute *ChangedAA = ChangedAAs[u];
2243 if (!Visited.insert(ChangedAA).second)
2244 continue;
2245
2246 AbstractState &State = ChangedAA->getState();
2247 if (!State.isAtFixpoint()) {
2249
2250 NumAttributesTimedOut++;
2251 }
2252
2253 for (auto &DepIt : ChangedAA->Deps)
2254 ChangedAAs.push_back(cast<AbstractAttribute>(DepIt.getPointer()));
2255 ChangedAA->Deps.clear();
2256 }
2257
2258 LLVM_DEBUG({
2259 if (!Visited.empty())
2260 dbgs() << "\n[Attributor] Finalized " << Visited.size()
2261 << " abstract attributes.\n";
2262 });
2263}
2264
2266 assert(AA.isQueryAA() &&
2267 "Non-query AAs should not be required to register for updates!");
2268 QueryAAsAwaitingUpdate.insert(&AA);
2269}
2270
2271ChangeStatus Attributor::manifestAttributes() {
2272 TimeTraceScope TimeScope("Attributor::manifestAttributes");
2273 size_t NumFinalAAs = DG.SyntheticRoot.Deps.size();
2274
2275 unsigned NumManifested = 0;
2276 unsigned NumAtFixpoint = 0;
2277 ChangeStatus ManifestChange = ChangeStatus::UNCHANGED;
2278 for (auto &DepAA : DG.SyntheticRoot.Deps) {
2279 AbstractAttribute *AA = cast<AbstractAttribute>(DepAA.getPointer());
2280 AbstractState &State = AA->getState();
2281
2282 // If there is not already a fixpoint reached, we can now take the
2283 // optimistic state. This is correct because we enforced a pessimistic one
2284 // on abstract attributes that were transitively dependent on a changed one
2285 // already above.
2286 if (!State.isAtFixpoint())
2288
2289 // We must not manifest Attributes that use Callbase info.
2290 if (AA->hasCallBaseContext())
2291 continue;
2292 // If the state is invalid, we do not try to manifest it.
2293 if (!State.isValidState())
2294 continue;
2295
2296 if (AA->getCtxI() && !isRunOn(*AA->getAnchorScope()))
2297 continue;
2298
2299 // Skip dead code.
2300 bool UsedAssumedInformation = false;
2301 if (isAssumedDead(*AA, nullptr, UsedAssumedInformation,
2302 /* CheckBBLivenessOnly */ true))
2303 continue;
2304 // Check if the manifest debug counter that allows skipping manifestation of
2305 // AAs
2306 if (!DebugCounter::shouldExecute(ManifestDBGCounter))
2307 continue;
2308 // Manifest the state and record if we changed the IR.
2309 ChangeStatus LocalChange = AA->manifest(*this);
2310 if (LocalChange == ChangeStatus::CHANGED && AreStatisticsEnabled())
2311 AA->trackStatistics();
2312 LLVM_DEBUG(dbgs() << "[Attributor] Manifest " << LocalChange << " : " << *AA
2313 << "\n");
2314
2315 ManifestChange = ManifestChange | LocalChange;
2316
2317 NumAtFixpoint++;
2318 NumManifested += (LocalChange == ChangeStatus::CHANGED);
2319 }
2320
2321 (void)NumManifested;
2322 (void)NumAtFixpoint;
2323 LLVM_DEBUG(dbgs() << "\n[Attributor] Manifested " << NumManifested
2324 << " arguments while " << NumAtFixpoint
2325 << " were in a valid fixpoint state\n");
2326
2327 NumAttributesManifested += NumManifested;
2328 NumAttributesValidFixpoint += NumAtFixpoint;
2329
2330 (void)NumFinalAAs;
2331 if (NumFinalAAs != DG.SyntheticRoot.Deps.size()) {
2332 auto DepIt = DG.SyntheticRoot.Deps.begin();
2333 for (unsigned u = 0; u < NumFinalAAs; ++u)
2334 ++DepIt;
2335 for (unsigned u = NumFinalAAs; u < DG.SyntheticRoot.Deps.size();
2336 ++u, ++DepIt) {
2337 errs() << "Unexpected abstract attribute: "
2338 << cast<AbstractAttribute>(DepIt->getPointer()) << " :: "
2339 << cast<AbstractAttribute>(DepIt->getPointer())
2340 ->getIRPosition()
2341 .getAssociatedValue()
2342 << "\n";
2343 }
2344 llvm_unreachable("Expected the final number of abstract attributes to "
2345 "remain unchanged!");
2346 }
2347
2348 for (auto &It : AttrsMap) {
2349 AttributeList &AL = It.getSecond();
2350 const IRPosition &IRP =
2351 isa<Function>(It.getFirst())
2352 ? IRPosition::function(*cast<Function>(It.getFirst()))
2353 : IRPosition::callsite_function(*cast<CallBase>(It.getFirst()));
2354 IRP.setAttrList(AL);
2355 }
2356
2357 return ManifestChange;
2358}
2359
2360void Attributor::identifyDeadInternalFunctions() {
2361 // Early exit if we don't intend to delete functions.
2362 if (!Configuration.DeleteFns)
2363 return;
2364
2365 // To avoid triggering an assertion in the lazy call graph we will not delete
2366 // any internal library functions. We should modify the assertion though and
2367 // allow internals to be deleted.
2368 const auto *TLI =
2369 isModulePass()
2370 ? nullptr
2372 LibFunc LF;
2373
2374 // Identify dead internal functions and delete them. This happens outside
2375 // the other fixpoint analysis as we might treat potentially dead functions
2376 // as live to lower the number of iterations. If they happen to be dead, the
2377 // below fixpoint loop will identify and eliminate them.
2378
2379 SmallVector<Function *, 8> InternalFns;
2380 for (Function *F : Functions)
2381 if (F->hasLocalLinkage() && (isModulePass() || !TLI->getLibFunc(*F, LF)))
2382 InternalFns.push_back(F);
2383
2384 SmallPtrSet<Function *, 8> LiveInternalFns;
2385 bool FoundLiveInternal = true;
2386 while (FoundLiveInternal) {
2387 FoundLiveInternal = false;
2388 for (Function *&F : InternalFns) {
2389 if (!F)
2390 continue;
2391
2392 bool UsedAssumedInformation = false;
2394 [&](AbstractCallSite ACS) {
2396 return ToBeDeletedFunctions.count(Callee) ||
2397 (Functions.count(Callee) && Callee->hasLocalLinkage() &&
2398 !LiveInternalFns.count(Callee));
2399 },
2400 *F, true, nullptr, UsedAssumedInformation)) {
2401 continue;
2402 }
2403
2404 LiveInternalFns.insert(F);
2405 F = nullptr;
2406 FoundLiveInternal = true;
2407 }
2408 }
2409
2410 for (Function *F : InternalFns)
2411 if (F)
2412 ToBeDeletedFunctions.insert(F);
2413}
2414
2415ChangeStatus Attributor::cleanupIR() {
2416 TimeTraceScope TimeScope("Attributor::cleanupIR");
2417 // Delete stuff at the end to avoid invalid references and a nice order.
2418 LLVM_DEBUG(dbgs() << "\n[Attributor] Delete/replace at least "
2419 << ToBeDeletedFunctions.size() << " functions and "
2420 << ToBeDeletedBlocks.size() << " blocks and "
2421 << ToBeDeletedInsts.size() << " instructions and "
2422 << ToBeChangedValues.size() << " values and "
2423 << ToBeChangedUses.size() << " uses. To insert "
2424 << ToBeChangedToUnreachableInsts.size()
2425 << " unreachables.\n"
2426 << "Preserve manifest added " << ManifestAddedBlocks.size()
2427 << " blocks\n");
2428
2430 SmallVector<Instruction *, 32> TerminatorsToFold;
2431
2432 auto ReplaceUse = [&](Use *U, Value *NewV) {
2433 Value *OldV = U->get();
2434
2435 // If we plan to replace NewV we need to update it at this point.
2436 do {
2437 const auto &Entry = ToBeChangedValues.lookup(NewV);
2438 if (!get<0>(Entry))
2439 break;
2440 NewV = get<0>(Entry);
2441 } while (true);
2442
2443 Instruction *I = dyn_cast<Instruction>(U->getUser());
2444 assert((!I || isRunOn(*I->getFunction())) &&
2445 "Cannot replace an instruction outside the current SCC!");
2446
2447 // Do not replace uses in returns if the value is a must-tail call we will
2448 // not delete.
2449 if (auto *RI = dyn_cast_or_null<ReturnInst>(I)) {
2450 if (auto *CI = dyn_cast<CallInst>(OldV->stripPointerCasts()))
2451 if (CI->isMustTailCall() && !ToBeDeletedInsts.count(CI))
2452 return;
2453 // If we rewrite a return and the new value is not an argument, strip the
2454 // `returned` attribute as it is wrong now.
2455 if (!isa<Argument>(NewV))
2456 for (auto &Arg : RI->getFunction()->args())
2457 Arg.removeAttr(Attribute::Returned);
2458 }
2459
2460 LLVM_DEBUG(dbgs() << "Use " << *NewV << " in " << *U->getUser()
2461 << " instead of " << *OldV << "\n");
2462 U->set(NewV);
2463
2464 if (Instruction *I = dyn_cast<Instruction>(OldV)) {
2465 CGModifiedFunctions.insert(I->getFunction());
2466 if (!isa<PHINode>(I) && !ToBeDeletedInsts.count(I) &&
2468 DeadInsts.push_back(I);
2469 }
2470 if (isa<UndefValue>(NewV) && isa<CallBase>(U->getUser())) {
2471 auto *CB = cast<CallBase>(U->getUser());
2472 if (CB->isArgOperand(U)) {
2473 unsigned Idx = CB->getArgOperandNo(U);
2474 CB->removeParamAttr(Idx, Attribute::NoUndef);
2475 auto *Callee = dyn_cast_if_present<Function>(CB->getCalledOperand());
2476 if (Callee && Callee->arg_size() > Idx)
2477 Callee->removeParamAttr(Idx, Attribute::NoUndef);
2478 }
2479 }
2480 if (isa<Constant>(NewV) && isa<BranchInst>(U->getUser())) {
2481 Instruction *UserI = cast<Instruction>(U->getUser());
2482 if (isa<UndefValue>(NewV)) {
2483 ToBeChangedToUnreachableInsts.insert(UserI);
2484 } else {
2485 TerminatorsToFold.push_back(UserI);
2486 }
2487 }
2488 };
2489
2490 for (auto &It : ToBeChangedUses) {
2491 Use *U = It.first;
2492 Value *NewV = It.second;
2493 ReplaceUse(U, NewV);
2494 }
2495
2497 for (auto &It : ToBeChangedValues) {
2498 Value *OldV = It.first;
2499 auto [NewV, Done] = It.second;
2500 Uses.clear();
2501 for (auto &U : OldV->uses())
2502 if (Done || !U.getUser()->isDroppable())
2503 Uses.push_back(&U);
2504 for (Use *U : Uses) {
2505 if (auto *I = dyn_cast<Instruction>(U->getUser()))
2506 if (!isRunOn(*I->getFunction()))
2507 continue;
2508 ReplaceUse(U, NewV);
2509 }
2510 }
2511
2512 for (const auto &V : InvokeWithDeadSuccessor)
2513 if (InvokeInst *II = dyn_cast_or_null<InvokeInst>(V)) {
2514 assert(isRunOn(*II->getFunction()) &&
2515 "Cannot replace an invoke outside the current SCC!");
2516 bool UnwindBBIsDead = II->hasFnAttr(Attribute::NoUnwind);
2517 bool NormalBBIsDead = II->hasFnAttr(Attribute::NoReturn);
2518 bool Invoke2CallAllowed =
2520 assert((UnwindBBIsDead || NormalBBIsDead) &&
2521 "Invoke does not have dead successors!");
2522 BasicBlock *BB = II->getParent();
2523 BasicBlock *NormalDestBB = II->getNormalDest();
2524 if (UnwindBBIsDead) {
2525 Instruction *NormalNextIP = &NormalDestBB->front();
2526 if (Invoke2CallAllowed) {
2528 NormalNextIP = BB->getTerminator();
2529 }
2530 if (NormalBBIsDead)
2531 ToBeChangedToUnreachableInsts.insert(NormalNextIP);
2532 } else {
2533 assert(NormalBBIsDead && "Broken invariant!");
2534 if (!NormalDestBB->getUniquePredecessor())
2535 NormalDestBB = SplitBlockPredecessors(NormalDestBB, {BB}, ".dead");
2536 ToBeChangedToUnreachableInsts.insert(&NormalDestBB->front());
2537 }
2538 }
2539 for (Instruction *I : TerminatorsToFold) {
2540 assert(isRunOn(*I->getFunction()) &&
2541 "Cannot replace a terminator outside the current SCC!");
2542 CGModifiedFunctions.insert(I->getFunction());
2543 ConstantFoldTerminator(I->getParent());
2544 }
2545 for (const auto &V : ToBeChangedToUnreachableInsts)
2546 if (Instruction *I = dyn_cast_or_null<Instruction>(V)) {
2547 LLVM_DEBUG(dbgs() << "[Attributor] Change to unreachable: " << *I
2548 << "\n");
2549 assert(isRunOn(*I->getFunction()) &&
2550 "Cannot replace an instruction outside the current SCC!");
2551 CGModifiedFunctions.insert(I->getFunction());
2553 }
2554
2555 for (const auto &V : ToBeDeletedInsts) {
2556 if (Instruction *I = dyn_cast_or_null<Instruction>(V)) {
2557 assert((!isa<CallBase>(I) || isa<IntrinsicInst>(I) ||
2558 isRunOn(*I->getFunction())) &&
2559 "Cannot delete an instruction outside the current SCC!");
2560 I->dropDroppableUses();
2561 CGModifiedFunctions.insert(I->getFunction());
2562 if (!I->getType()->isVoidTy())
2563 I->replaceAllUsesWith(UndefValue::get(I->getType()));
2564 if (!isa<PHINode>(I) && isInstructionTriviallyDead(I))
2565 DeadInsts.push_back(I);
2566 else
2567 I->eraseFromParent();
2568 }
2569 }
2570
2571 llvm::erase_if(DeadInsts, [&](WeakTrackingVH I) { return !I; });
2572
2573 LLVM_DEBUG({
2574 dbgs() << "[Attributor] DeadInsts size: " << DeadInsts.size() << "\n";
2575 for (auto &I : DeadInsts)
2576 if (I)
2577 dbgs() << " - " << *I << "\n";
2578 });
2579
2581
2582 if (unsigned NumDeadBlocks = ToBeDeletedBlocks.size()) {
2583 SmallVector<BasicBlock *, 8> ToBeDeletedBBs;
2584 ToBeDeletedBBs.reserve(NumDeadBlocks);
2585 for (BasicBlock *BB : ToBeDeletedBlocks) {
2586 assert(isRunOn(*BB->getParent()) &&
2587 "Cannot delete a block outside the current SCC!");
2588 CGModifiedFunctions.insert(BB->getParent());
2589 // Do not delete BBs added during manifests of AAs.
2590 if (ManifestAddedBlocks.contains(BB))
2591 continue;
2592 ToBeDeletedBBs.push_back(BB);
2593 }
2594 // Actually we do not delete the blocks but squash them into a single
2595 // unreachable but untangling branches that jump here is something we need
2596 // to do in a more generic way.
2597 detachDeadBlocks(ToBeDeletedBBs, nullptr);
2598 }
2599
2600 identifyDeadInternalFunctions();
2601
2602 // Rewrite the functions as requested during manifest.
2603 ChangeStatus ManifestChange = rewriteFunctionSignatures(CGModifiedFunctions);
2604
2605 for (Function *Fn : CGModifiedFunctions)
2606 if (!ToBeDeletedFunctions.count(Fn) && Functions.count(Fn))
2607 Configuration.CGUpdater.reanalyzeFunction(*Fn);
2608
2609 for (Function *Fn : ToBeDeletedFunctions) {
2610 if (!Functions.count(Fn))
2611 continue;
2612 Configuration.CGUpdater.removeFunction(*Fn);
2613 }
2614
2615 if (!ToBeChangedUses.empty())
2616 ManifestChange = ChangeStatus::CHANGED;
2617
2618 if (!ToBeChangedToUnreachableInsts.empty())
2619 ManifestChange = ChangeStatus::CHANGED;
2620
2621 if (!ToBeDeletedFunctions.empty())
2622 ManifestChange = ChangeStatus::CHANGED;
2623
2624 if (!ToBeDeletedBlocks.empty())
2625 ManifestChange = ChangeStatus::CHANGED;
2626
2627 if (!ToBeDeletedInsts.empty())
2628 ManifestChange = ChangeStatus::CHANGED;
2629
2630 if (!InvokeWithDeadSuccessor.empty())
2631 ManifestChange = ChangeStatus::CHANGED;
2632
2633 if (!DeadInsts.empty())
2634 ManifestChange = ChangeStatus::CHANGED;
2635
2636 NumFnDeleted += ToBeDeletedFunctions.size();
2637
2638 LLVM_DEBUG(dbgs() << "[Attributor] Deleted " << ToBeDeletedFunctions.size()
2639 << " functions after manifest.\n");
2640
2641#ifdef EXPENSIVE_CHECKS
2642 for (Function *F : Functions) {
2643 if (ToBeDeletedFunctions.count(F))
2644 continue;
2645 assert(!verifyFunction(*F, &errs()) && "Module verification failed!");
2646 }
2647#endif
2648
2649 return ManifestChange;
2650}
2651
2653 TimeTraceScope TimeScope("Attributor::run");
2654 AttributorCallGraph ACallGraph(*this);
2655
2656 if (PrintCallGraph)
2657 ACallGraph.populateAll();
2658
2659 Phase = AttributorPhase::UPDATE;
2660 runTillFixpoint();
2661
2662 // dump graphs on demand
2663 if (DumpDepGraph)
2664 DG.dumpGraph();
2665
2666 if (ViewDepGraph)
2667 DG.viewGraph();
2668
2670 DG.print();
2671
2672 Phase = AttributorPhase::MANIFEST;
2673 ChangeStatus ManifestChange = manifestAttributes();
2674
2675 Phase = AttributorPhase::CLEANUP;
2676 ChangeStatus CleanupChange = cleanupIR();
2677
2678 if (PrintCallGraph)
2679 ACallGraph.print();
2680
2681 return ManifestChange | CleanupChange;
2682}
2683
2684ChangeStatus Attributor::updateAA(AbstractAttribute &AA) {
2685 TimeTraceScope TimeScope("updateAA", [&]() {
2686 return AA.getName() + std::to_string(AA.getIRPosition().getPositionKind());
2687 });
2688 assert(Phase == AttributorPhase::UPDATE &&
2689 "We can update AA only in the update stage!");
2690
2691 // Use a new dependence vector for this update.
2692 DependenceVector DV;
2693 DependenceStack.push_back(&DV);
2694
2695 auto &AAState = AA.getState();
2697 bool UsedAssumedInformation = false;
2698 if (!isAssumedDead(AA, nullptr, UsedAssumedInformation,
2699 /* CheckBBLivenessOnly */ true))
2700 CS = AA.update(*this);
2701
2702 if (!AA.isQueryAA() && DV.empty() && !AA.getState().isAtFixpoint()) {
2703 // If the AA did not rely on outside information but changed, we run it
2704 // again to see if it found a fixpoint. Most AAs do but we don't require
2705 // them to. Hence, it might take the AA multiple iterations to get to a
2706 // fixpoint even if it does not rely on outside information, which is fine.
2708 if (CS == ChangeStatus::CHANGED)
2709 RerunCS = AA.update(*this);
2710
2711 // If the attribute did not change during the run or rerun, and it still did
2712 // not query any non-fix information, the state will not change and we can
2713 // indicate that right at this point.
2714 if (RerunCS == ChangeStatus::UNCHANGED && !AA.isQueryAA() && DV.empty())
2715 AAState.indicateOptimisticFixpoint();
2716 }
2717
2718 if (!AAState.isAtFixpoint())
2719 rememberDependences();
2720
2721 // Verify the stack was used properly, that is we pop the dependence vector we
2722 // put there earlier.
2723 DependenceVector *PoppedDV = DependenceStack.pop_back_val();
2724 (void)PoppedDV;
2725 assert(PoppedDV == &DV && "Inconsistent usage of the dependence stack!");
2726
2727 return CS;
2728}
2729
2731 assert(!F.isDeclaration() && "Cannot create a wrapper around a declaration!");
2732
2733 Module &M = *F.getParent();
2734 LLVMContext &Ctx = M.getContext();
2735 FunctionType *FnTy = F.getFunctionType();
2736
2737 Function *Wrapper =
2738 Function::Create(FnTy, F.getLinkage(), F.getAddressSpace(), F.getName());
2739 F.setName(""); // set the inside function anonymous
2740 M.getFunctionList().insert(F.getIterator(), Wrapper);
2741 // Flag whether the function is using new-debug-info or not.
2742 Wrapper->IsNewDbgInfoFormat = M.IsNewDbgInfoFormat;
2743
2744 F.setLinkage(GlobalValue::InternalLinkage);
2745
2746 F.replaceAllUsesWith(Wrapper);
2747 assert(F.use_empty() && "Uses remained after wrapper was created!");
2748
2749 // Move the COMDAT section to the wrapper.
2750 // TODO: Check if we need to keep it for F as well.
2751 Wrapper->setComdat(F.getComdat());
2752 F.setComdat(nullptr);
2753
2754 // Copy all metadata and attributes but keep them on F as well.
2756 F.getAllMetadata(MDs);
2757 for (auto MDIt : MDs)
2758 Wrapper->addMetadata(MDIt.first, *MDIt.second);
2759 Wrapper->setAttributes(F.getAttributes());
2760
2761 // Create the call in the wrapper.
2762 BasicBlock *EntryBB = BasicBlock::Create(Ctx, "entry", Wrapper);
2763
2765 Argument *FArgIt = F.arg_begin();
2766 for (Argument &Arg : Wrapper->args()) {
2767 Args.push_back(&Arg);
2768 Arg.setName((FArgIt++)->getName());
2769 }
2770
2771 CallInst *CI = CallInst::Create(&F, Args, "", EntryBB);
2772 CI->setTailCall(true);
2773 CI->addFnAttr(Attribute::NoInline);
2774 ReturnInst::Create(Ctx, CI->getType()->isVoidTy() ? nullptr : CI, EntryBB);
2775
2776 NumFnShallowWrappersCreated++;
2777}
2778
2780 if (F.isDeclaration() || F.hasLocalLinkage() ||
2782 return false;
2783 return true;
2784}
2785
2787 if (!AllowDeepWrapper && !Force)
2788 return nullptr;
2789 if (!isInternalizable(F))
2790 return nullptr;
2791
2792 SmallPtrSet<Function *, 2> FnSet = {&F};
2793 DenseMap<Function *, Function *> InternalizedFns;
2794 internalizeFunctions(FnSet, InternalizedFns);
2795
2796 return InternalizedFns[&F];
2797}
2798
2801 for (Function *F : FnSet)
2803 return false;
2804
2805 FnMap.clear();
2806 // Generate the internalized version of each function.
2807 for (Function *F : FnSet) {
2808 Module &M = *F->getParent();
2809 FunctionType *FnTy = F->getFunctionType();
2810
2811 // Create a copy of the current function
2812 Function *Copied =
2813 Function::Create(FnTy, F->getLinkage(), F->getAddressSpace(),
2814 F->getName() + ".internalized");
2815 ValueToValueMapTy VMap;
2816 auto *NewFArgIt = Copied->arg_begin();
2817 for (auto &Arg : F->args()) {
2818 auto ArgName = Arg.getName();
2819 NewFArgIt->setName(ArgName);
2820 VMap[&Arg] = &(*NewFArgIt++);
2821 }
2823 // Flag whether the function is using new-debug-info or not.
2824 Copied->IsNewDbgInfoFormat = F->IsNewDbgInfoFormat;
2825
2826 // Copy the body of the original function to the new one
2827 CloneFunctionInto(Copied, F, VMap,
2829
2830 // Set the linakage and visibility late as CloneFunctionInto has some
2831 // implicit requirements.
2834
2835 // Copy metadata
2837 F->getAllMetadata(MDs);
2838 for (auto MDIt : MDs)
2839 if (!Copied->hasMetadata())
2840 Copied->addMetadata(MDIt.first, *MDIt.second);
2841
2842 M.getFunctionList().insert(F->getIterator(), Copied);
2843 Copied->setDSOLocal(true);
2844 FnMap[F] = Copied;
2845 }
2846
2847 // Replace all uses of the old function with the new internalized function
2848 // unless the caller is a function that was just internalized.
2849 for (Function *F : FnSet) {
2850 auto &InternalizedFn = FnMap[F];
2851 auto IsNotInternalized = [&](Use &U) -> bool {
2852 if (auto *CB = dyn_cast<CallBase>(U.getUser()))
2853 return !FnMap.lookup(CB->getCaller());
2854 return false;
2855 };
2856 F->replaceUsesWithIf(InternalizedFn, IsNotInternalized);
2857 }
2858
2859 return true;
2860}
2861
2863 Argument &Arg, ArrayRef<Type *> ReplacementTypes) {
2864
2865 if (!Configuration.RewriteSignatures)
2866 return false;
2867
2868 Function *Fn = Arg.getParent();
2869 auto CallSiteCanBeChanged = [Fn](AbstractCallSite ACS) {
2870 // Forbid the call site to cast the function return type. If we need to
2871 // rewrite these functions we need to re-create a cast for the new call site
2872 // (if the old had uses).
2873 if (!ACS.getCalledFunction() ||
2874 ACS.getInstruction()->getType() !=
2876 return false;
2877 if (cast<CallBase>(ACS.getInstruction())->getCalledOperand()->getType() !=
2878 Fn->getType())
2879 return false;
2880 if (ACS.getNumArgOperands() != Fn->arg_size())
2881 return false;
2882 // Forbid must-tail calls for now.
2883 return !ACS.isCallbackCall() && !ACS.getInstruction()->isMustTailCall();
2884 };
2885
2886 // Avoid var-arg functions for now.
2887 if (Fn->isVarArg()) {
2888 LLVM_DEBUG(dbgs() << "[Attributor] Cannot rewrite var-args functions\n");
2889 return false;
2890 }
2891
2892 // Avoid functions with complicated argument passing semantics.
2893 AttributeList FnAttributeList = Fn->getAttributes();
2894 if (FnAttributeList.hasAttrSomewhere(Attribute::Nest) ||
2895 FnAttributeList.hasAttrSomewhere(Attribute::StructRet) ||
2896 FnAttributeList.hasAttrSomewhere(Attribute::InAlloca) ||
2897 FnAttributeList.hasAttrSomewhere(Attribute::Preallocated)) {
2898 LLVM_DEBUG(
2899 dbgs() << "[Attributor] Cannot rewrite due to complex attribute\n");
2900 return false;
2901 }
2902
2903 // Avoid callbacks for now.
2904 bool UsedAssumedInformation = false;
2905 if (!checkForAllCallSites(CallSiteCanBeChanged, *Fn, true, nullptr,
2906 UsedAssumedInformation,
2907 /* CheckPotentiallyDead */ true)) {
2908 LLVM_DEBUG(dbgs() << "[Attributor] Cannot rewrite all call sites\n");
2909 return false;
2910 }
2911
2912 auto InstPred = [](Instruction &I) {
2913 if (auto *CI = dyn_cast<CallInst>(&I))
2914 return !CI->isMustTailCall();
2915 return true;
2916 };
2917
2918 // Forbid must-tail calls for now.
2919 // TODO:
2920 auto &OpcodeInstMap = InfoCache.getOpcodeInstMapForFunction(*Fn);
2921 if (!checkForAllInstructionsImpl(nullptr, OpcodeInstMap, InstPred, nullptr,
2922 nullptr, {Instruction::Call},
2923 UsedAssumedInformation)) {
2924 LLVM_DEBUG(dbgs() << "[Attributor] Cannot rewrite due to instructions\n");
2925 return false;
2926 }
2927
2928 return true;
2929}
2930
2932 Argument &Arg, ArrayRef<Type *> ReplacementTypes,
2935 LLVM_DEBUG(dbgs() << "[Attributor] Register new rewrite of " << Arg << " in "
2936 << Arg.getParent()->getName() << " with "
2937 << ReplacementTypes.size() << " replacements\n");
2938 assert(isValidFunctionSignatureRewrite(Arg, ReplacementTypes) &&
2939 "Cannot register an invalid rewrite");
2940
2941 Function *Fn = Arg.getParent();
2943 ArgumentReplacementMap[Fn];
2944 if (ARIs.empty())
2945 ARIs.resize(Fn->arg_size());
2946
2947 // If we have a replacement already with less than or equal new arguments,
2948 // ignore this request.
2949 std::unique_ptr<ArgumentReplacementInfo> &ARI = ARIs[Arg.getArgNo()];
2950 if (ARI && ARI->getNumReplacementArgs() <= ReplacementTypes.size()) {
2951 LLVM_DEBUG(dbgs() << "[Attributor] Existing rewrite is preferred\n");
2952 return false;
2953 }
2954
2955 // If we have a replacement already but we like the new one better, delete
2956 // the old.
2957 ARI.reset();
2958
2959 LLVM_DEBUG(dbgs() << "[Attributor] Register new rewrite of " << Arg << " in "
2960 << Arg.getParent()->getName() << " with "
2961 << ReplacementTypes.size() << " replacements\n");
2962
2963 // Remember the replacement.
2964 ARI.reset(new ArgumentReplacementInfo(*this, Arg, ReplacementTypes,
2965 std::move(CalleeRepairCB),
2966 std::move(ACSRepairCB)));
2967
2968 return true;
2969}
2970
2971bool Attributor::shouldSeedAttribute(AbstractAttribute &AA) {
2972 bool Result = true;
2973#ifndef NDEBUG
2974 if (SeedAllowList.size() != 0)
2976 Function *Fn = AA.getAnchorScope();
2977 if (FunctionSeedAllowList.size() != 0 && Fn)
2979#endif
2980 return Result;
2981}
2982
2983ChangeStatus Attributor::rewriteFunctionSignatures(
2984 SmallSetVector<Function *, 8> &ModifiedFns) {
2986
2987 for (auto &It : ArgumentReplacementMap) {
2988 Function *OldFn = It.getFirst();
2989
2990 // Deleted functions do not require rewrites.
2991 if (!Functions.count(OldFn) || ToBeDeletedFunctions.count(OldFn))
2992 continue;
2993
2995 It.getSecond();
2996 assert(ARIs.size() == OldFn->arg_size() && "Inconsistent state!");
2997
2998 SmallVector<Type *, 16> NewArgumentTypes;
2999 SmallVector<AttributeSet, 16> NewArgumentAttributes;
3000
3001 // Collect replacement argument types and copy over existing attributes.
3002 AttributeList OldFnAttributeList = OldFn->getAttributes();
3003 for (Argument &Arg : OldFn->args()) {
3004 if (const std::unique_ptr<ArgumentReplacementInfo> &ARI =
3005 ARIs[Arg.getArgNo()]) {
3006 NewArgumentTypes.append(ARI->ReplacementTypes.begin(),
3007 ARI->ReplacementTypes.end());
3008 NewArgumentAttributes.append(ARI->getNumReplacementArgs(),
3009 AttributeSet());
3010 } else {
3011 NewArgumentTypes.push_back(Arg.getType());
3012 NewArgumentAttributes.push_back(
3013 OldFnAttributeList.getParamAttrs(Arg.getArgNo()));
3014 }
3015 }
3016
3017 uint64_t LargestVectorWidth = 0;
3018 for (auto *I : NewArgumentTypes)
3019 if (auto *VT = dyn_cast<llvm::VectorType>(I))
3020 LargestVectorWidth =
3021 std::max(LargestVectorWidth,
3022 VT->getPrimitiveSizeInBits().getKnownMinValue());
3023
3024 FunctionType *OldFnTy = OldFn->getFunctionType();
3025 Type *RetTy = OldFnTy->getReturnType();
3026
3027 // Construct the new function type using the new arguments types.
3028 FunctionType *NewFnTy =
3029 FunctionType::get(RetTy, NewArgumentTypes, OldFnTy->isVarArg());
3030
3031 LLVM_DEBUG(dbgs() << "[Attributor] Function rewrite '" << OldFn->getName()
3032 << "' from " << *OldFn->getFunctionType() << " to "
3033 << *NewFnTy << "\n");
3034
3035 // Create the new function body and insert it into the module.
3036 Function *NewFn = Function::Create(NewFnTy, OldFn->getLinkage(),
3037 OldFn->getAddressSpace(), "");
3038 Functions.insert(NewFn);
3039 OldFn->getParent()->getFunctionList().insert(OldFn->getIterator(), NewFn);
3040 NewFn->takeName(OldFn);
3041 NewFn->copyAttributesFrom(OldFn);
3042 // Flag whether the function is using new-debug-info or not.
3043 NewFn->IsNewDbgInfoFormat = OldFn->IsNewDbgInfoFormat;
3044
3045 // Patch the pointer to LLVM function in debug info descriptor.
3046 NewFn->setSubprogram(OldFn->getSubprogram());
3047 OldFn->setSubprogram(nullptr);
3048
3049 // Recompute the parameter attributes list based on the new arguments for
3050 // the function.
3051 LLVMContext &Ctx = OldFn->getContext();
3053 Ctx, OldFnAttributeList.getFnAttrs(), OldFnAttributeList.getRetAttrs(),
3054 NewArgumentAttributes));
3055 AttributeFuncs::updateMinLegalVectorWidthAttr(*NewFn, LargestVectorWidth);
3056
3057 // Remove argmem from the memory effects if we have no more pointer
3058 // arguments, or they are readnone.
3059 MemoryEffects ME = NewFn->getMemoryEffects();
3060 int ArgNo = -1;
3061 if (ME.doesAccessArgPointees() && all_of(NewArgumentTypes, [&](Type *T) {
3062 ++ArgNo;
3063 return !T->isPtrOrPtrVectorTy() ||
3064 NewFn->hasParamAttribute(ArgNo, Attribute::ReadNone);
3065 })) {
3067 }
3068
3069 // Since we have now created the new function, splice the body of the old
3070 // function right into the new function, leaving the old rotting hulk of the
3071 // function empty.
3072 NewFn->splice(NewFn->begin(), OldFn);
3073
3074 // Fixup block addresses to reference new function.
3075 SmallVector<BlockAddress *, 8u> BlockAddresses;
3076 for (User *U : OldFn->users())
3077 if (auto *BA = dyn_cast<BlockAddress>(U))
3078 BlockAddresses.push_back(BA);
3079 for (auto *BA : BlockAddresses)
3080 BA->replaceAllUsesWith(BlockAddress::get(NewFn, BA->getBasicBlock()));
3081
3082 // Set of all "call-like" instructions that invoke the old function mapped
3083 // to their new replacements.
3085
3086 // Callback to create a new "call-like" instruction for a given one.
3087 auto CallSiteReplacementCreator = [&](AbstractCallSite ACS) {
3088 CallBase *OldCB = cast<CallBase>(ACS.getInstruction());
3089 const AttributeList &OldCallAttributeList = OldCB->getAttributes();
3090
3091 // Collect the new argument operands for the replacement call site.
3092 SmallVector<Value *, 16> NewArgOperands;
3093 SmallVector<AttributeSet, 16> NewArgOperandAttributes;
3094 for (unsigned OldArgNum = 0; OldArgNum < ARIs.size(); ++OldArgNum) {
3095 unsigned NewFirstArgNum = NewArgOperands.size();
3096 (void)NewFirstArgNum; // only used inside assert.
3097 if (const std::unique_ptr<ArgumentReplacementInfo> &ARI =
3098 ARIs[OldArgNum]) {
3099 if (ARI->ACSRepairCB)
3100 ARI->ACSRepairCB(*ARI, ACS, NewArgOperands);
3101 assert(ARI->getNumReplacementArgs() + NewFirstArgNum ==
3102 NewArgOperands.size() &&
3103 "ACS repair callback did not provide as many operand as new "
3104 "types were registered!");
3105 // TODO: Exose the attribute set to the ACS repair callback
3106 NewArgOperandAttributes.append(ARI->ReplacementTypes.size(),
3107 AttributeSet());
3108 } else {
3109 NewArgOperands.push_back(ACS.getCallArgOperand(OldArgNum));
3110 NewArgOperandAttributes.push_back(
3111 OldCallAttributeList.getParamAttrs(OldArgNum));
3112 }
3113 }
3114
3115 assert(NewArgOperands.size() == NewArgOperandAttributes.size() &&
3116 "Mismatch # argument operands vs. # argument operand attributes!");
3117 assert(NewArgOperands.size() == NewFn->arg_size() &&
3118 "Mismatch # argument operands vs. # function arguments!");
3119
3120 SmallVector<OperandBundleDef, 4> OperandBundleDefs;
3121 OldCB->getOperandBundlesAsDefs(OperandBundleDefs);
3122
3123 // Create a new call or invoke instruction to replace the old one.
3124 CallBase *NewCB;
3125 if (InvokeInst *II = dyn_cast<InvokeInst>(OldCB)) {
3126 NewCB = InvokeInst::Create(NewFn, II->getNormalDest(),
3127 II->getUnwindDest(), NewArgOperands,
3128 OperandBundleDefs, "", OldCB->getIterator());
3129 } else {
3130 auto *NewCI = CallInst::Create(NewFn, NewArgOperands, OperandBundleDefs,
3131 "", OldCB->getIterator());
3132 NewCI->setTailCallKind(cast<CallInst>(OldCB)->getTailCallKind());
3133 NewCB = NewCI;
3134 }
3135
3136 // Copy over various properties and the new attributes.
3137 NewCB->copyMetadata(*OldCB, {LLVMContext::MD_prof, LLVMContext::MD_dbg});
3138 NewCB->setCallingConv(OldCB->getCallingConv());
3139 NewCB->takeName(OldCB);
3141 Ctx, OldCallAttributeList.getFnAttrs(),
3142 OldCallAttributeList.getRetAttrs(), NewArgOperandAttributes));
3143
3145 LargestVectorWidth);
3146
3147 CallSitePairs.push_back({OldCB, NewCB});
3148 return true;
3149 };
3150
3151 // Use the CallSiteReplacementCreator to create replacement call sites.
3152 bool UsedAssumedInformation = false;
3153 bool Success = checkForAllCallSites(CallSiteReplacementCreator, *OldFn,
3154 true, nullptr, UsedAssumedInformation,
3155 /* CheckPotentiallyDead */ true);
3156 (void)Success;
3157 assert(Success && "Assumed call site replacement to succeed!");
3158
3159 // Rewire the arguments.
3160 Argument *OldFnArgIt = OldFn->arg_begin();
3161 Argument *NewFnArgIt = NewFn->arg_begin();
3162 for (unsigned OldArgNum = 0; OldArgNum < ARIs.size();
3163 ++OldArgNum, ++OldFnArgIt) {
3164 if (const std::unique_ptr<ArgumentReplacementInfo> &ARI =
3165 ARIs[OldArgNum]) {
3166 if (ARI->CalleeRepairCB)
3167 ARI->CalleeRepairCB(*ARI, *NewFn, NewFnArgIt);
3168 if (ARI->ReplacementTypes.empty())
3169 OldFnArgIt->replaceAllUsesWith(
3170 PoisonValue::get(OldFnArgIt->getType()));
3171 NewFnArgIt += ARI->ReplacementTypes.size();
3172 } else {
3173 NewFnArgIt->takeName(&*OldFnArgIt);
3174 OldFnArgIt->replaceAllUsesWith(&*NewFnArgIt);
3175 ++NewFnArgIt;
3176 }
3177 }
3178
3179 // Eliminate the instructions *after* we visited all of them.
3180 for (auto &CallSitePair : CallSitePairs) {
3181 CallBase &OldCB = *CallSitePair.first;
3182 CallBase &NewCB = *CallSitePair.second;
3183 assert(OldCB.getType() == NewCB.getType() &&
3184 "Cannot handle call sites with different types!");
3185 ModifiedFns.insert(OldCB.getFunction());
3186 OldCB.replaceAllUsesWith(&NewCB);
3187 OldCB.eraseFromParent();
3188 }
3189
3190 // Replace the function in the call graph (if any).
3191 Configuration.CGUpdater.replaceFunctionWith(*OldFn, *NewFn);
3192
3193 // If the old function was modified and needed to be reanalyzed, the new one
3194 // does now.
3195 if (ModifiedFns.remove(OldFn))
3196 ModifiedFns.insert(NewFn);
3197
3198 Changed = ChangeStatus::CHANGED;
3199 }
3200
3201 return Changed;
3202}
3203
3204void InformationCache::initializeInformationCache(const Function &CF,
3205 FunctionInfo &FI) {
3206 // As we do not modify the function here we can remove the const
3207 // withouth breaking implicit assumptions. At the end of the day, we could
3208 // initialize the cache eagerly which would look the same to the users.
3209 Function &F = const_cast<Function &>(CF);
3210
3211 // Walk all instructions to find interesting instructions that might be
3212 // queried by abstract attributes during their initialization or update.
3213 // This has to happen before we create attributes.
3214
3216
3217 // Add \p V to the assume uses map which track the number of uses outside of
3218 // "visited" assumes. If no outside uses are left the value is added to the
3219 // assume only use vector.
3220 auto AddToAssumeUsesMap = [&](const Value &V) -> void {
3222 if (auto *I = dyn_cast<Instruction>(&V))
3223 Worklist.push_back(I);
3224 while (!Worklist.empty()) {
3225 const Instruction *I = Worklist.pop_back_val();
3226 std::optional<short> &NumUses = AssumeUsesMap[I];
3227 if (!NumUses)
3228 NumUses = I->getNumUses();
3229 NumUses = *NumUses - /* this assume */ 1;
3230 if (*NumUses != 0)
3231 continue;
3232 AssumeOnlyValues.insert(I);
3233 for (const Value *Op : I->operands())
3234 if (auto *OpI = dyn_cast<Instruction>(Op))
3235 Worklist.push_back(OpI);
3236 }
3237 };
3238
3239 for (Instruction &I : instructions(&F)) {
3240 bool IsInterestingOpcode = false;
3241
3242 // To allow easy access to all instructions in a function with a given
3243 // opcode we store them in the InfoCache. As not all opcodes are interesting
3244 // to concrete attributes we only cache the ones that are as identified in
3245 // the following switch.
3246 // Note: There are no concrete attributes now so this is initially empty.
3247 switch (I.getOpcode()) {
3248 default:
3249 assert(!isa<CallBase>(&I) &&
3250 "New call base instruction type needs to be known in the "
3251 "Attributor.");
3252 break;
3253 case Instruction::Call:
3254 // Calls are interesting on their own, additionally:
3255 // For `llvm.assume` calls we also fill the KnowledgeMap as we find them.
3256 // For `must-tail` calls we remember the caller and callee.
3257 if (auto *Assume = dyn_cast<AssumeInst>(&I)) {
3258 AssumeOnlyValues.insert(Assume);
3259 fillMapFromAssume(*Assume, KnowledgeMap);
3260 AddToAssumeUsesMap(*Assume->getArgOperand(0));
3261 } else if (cast<CallInst>(I).isMustTailCall()) {
3262 FI.ContainsMustTailCall = true;
3263 if (auto *Callee = dyn_cast_if_present<Function>(
3264 cast<CallInst>(I).getCalledOperand()))
3265 getFunctionInfo(*Callee).CalledViaMustTail = true;
3266 }
3267 [[fallthrough]];
3268 case Instruction::CallBr:
3269 case Instruction::Invoke:
3270 case Instruction::CleanupRet:
3271 case Instruction::CatchSwitch:
3272 case Instruction::AtomicRMW:
3273 case Instruction::AtomicCmpXchg:
3274 case Instruction::Br:
3275 case Instruction::Resume:
3276 case Instruction::Ret:
3277 case Instruction::Load:
3278 // The alignment of a pointer is interesting for loads.
3279 case Instruction::Store:
3280 // The alignment of a pointer is interesting for stores.
3281 case Instruction::Alloca:
3282 case Instruction::AddrSpaceCast:
3283 IsInterestingOpcode = true;
3284 }
3285 if (IsInterestingOpcode) {
3286 auto *&Insts = FI.OpcodeInstMap[I.getOpcode()];
3287 if (!Insts)
3288 Insts = new (Allocator) InstructionVectorTy();
3289 Insts->push_back(&I);
3290 }
3291 if (I.mayReadOrWriteMemory())
3292 FI.RWInsts.push_back(&I);
3293 }
3294
3295 if (F.hasFnAttribute(Attribute::AlwaysInline) &&
3297 InlineableFunctions.insert(&F);
3298}
3299
3300InformationCache::FunctionInfo::~FunctionInfo() {
3301 // The instruction vectors are allocated using a BumpPtrAllocator, we need to
3302 // manually destroy them.
3303 for (auto &It : OpcodeInstMap)
3304 It.getSecond()->~InstructionVectorTy();
3305}
3306
3309 assert(A.isClosedWorldModule() && "Cannot see all indirect callees!");
3310 return IndirectlyCallableFunctions;
3311}
3312
3314 const AbstractAttribute &ToAA,
3315 DepClassTy DepClass) {
3316 if (DepClass == DepClassTy::NONE)
3317 return;
3318 // If we are outside of an update, thus before the actual fixpoint iteration
3319 // started (= when we create AAs), we do not track dependences because we will
3320 // put all AAs into the initial worklist anyway.
3321 if (DependenceStack.empty())
3322 return;
3323 if (FromAA.getState().isAtFixpoint())
3324 return;
3325 DependenceStack.back()->push_back({&FromAA, &ToAA, DepClass});
3326}
3327
3328void Attributor::rememberDependences() {
3329 assert(!DependenceStack.empty() && "No dependences to remember!");
3330
3331 for (DepInfo &DI : *DependenceStack.back()) {
3332 assert((DI.DepClass == DepClassTy::REQUIRED ||
3333 DI.DepClass == DepClassTy::OPTIONAL) &&
3334 "Expected required or optional dependence (1 bit)!");
3335 auto &DepAAs = const_cast<AbstractAttribute &>(*DI.FromAA).Deps;
3336 DepAAs.insert(AbstractAttribute::DepTy(
3337 const_cast<AbstractAttribute *>(DI.ToAA), unsigned(DI.DepClass)));
3338 }
3339}
3340
3341template <Attribute::AttrKind AK, typename AAType>
3342void Attributor::checkAndQueryIRAttr(const IRPosition &IRP,
3343 AttributeSet Attrs) {
3344 bool IsKnown;
3345 if (!Attrs.hasAttribute(AK))
3346 if (!Configuration.Allowed || Configuration.Allowed->count(&AAType::ID))
3347 if (!AA::hasAssumedIRAttr<AK>(*this, nullptr, IRP, DepClassTy::NONE,
3348 IsKnown))
3349 getOrCreateAAFor<AAType>(IRP);
3350}
3351
3353 if (!VisitedFunctions.insert(&F).second)
3354 return;
3355 if (F.isDeclaration())
3356 return;
3357
3358 // In non-module runs we need to look at the call sites of a function to
3359 // determine if it is part of a must-tail call edge. This will influence what
3360 // attributes we can derive.
3361 InformationCache::FunctionInfo &FI = InfoCache.getFunctionInfo(F);
3362 if (!isModulePass() && !FI.CalledViaMustTail) {
3363 for (const Use &U : F.uses())
3364 if (const auto *CB = dyn_cast<CallBase>(U.getUser()))
3365 if (CB->isCallee(&U) && CB->isMustTailCall())
3366 FI.CalledViaMustTail = true;
3367 }
3368
3370 bool IsIPOAmendable = isFunctionIPOAmendable(F);
3371 auto Attrs = F.getAttributes();
3372 auto FnAttrs = Attrs.getFnAttrs();
3373
3374 // Check for dead BasicBlocks in every function.
3375 // We need dead instruction detection because we do not want to deal with
3376 // broken IR in which SSA rules do not apply.
3377 getOrCreateAAFor<AAIsDead>(FPos);
3378
3379 // Every function might contain instructions that cause "undefined
3380 // behavior".
3381 getOrCreateAAFor<AAUndefinedBehavior>(FPos);
3382
3383 // Every function might be applicable for Heap-To-Stack conversion.
3385 getOrCreateAAFor<AAHeapToStack>(FPos);
3386
3387 // Every function might be "must-progress".
3388 checkAndQueryIRAttr<Attribute::MustProgress, AAMustProgress>(FPos, FnAttrs);
3389
3390 // Every function might be "no-free".
3391 checkAndQueryIRAttr<Attribute::NoFree, AANoFree>(FPos, FnAttrs);
3392
3393 // Every function might be "will-return".
3394 checkAndQueryIRAttr<Attribute::WillReturn, AAWillReturn>(FPos, FnAttrs);
3395
3396 // Every function might be marked "nosync"
3397 checkAndQueryIRAttr<Attribute::NoSync, AANoSync>(FPos, FnAttrs);
3398
3399 // Everything that is visible from the outside (=function, argument, return
3400 // positions), cannot be changed if the function is not IPO amendable. We can
3401 // however analyse the code inside.
3402 if (IsIPOAmendable) {
3403
3404 // Every function can be nounwind.
3405 checkAndQueryIRAttr<Attribute::NoUnwind, AANoUnwind>(FPos, FnAttrs);
3406
3407 // Every function might be "no-return".
3408 checkAndQueryIRAttr<Attribute::NoReturn, AANoReturn>(FPos, FnAttrs);
3409
3410 // Every function might be "no-recurse".
3411 checkAndQueryIRAttr<Attribute::NoRecurse, AANoRecurse>(FPos, FnAttrs);
3412
3413 // Every function can be "non-convergent".
3414 if (Attrs.hasFnAttr(Attribute::Convergent))
3415 getOrCreateAAFor<AANonConvergent>(FPos);
3416
3417 // Every function might be "readnone/readonly/writeonly/...".
3418 getOrCreateAAFor<AAMemoryBehavior>(FPos);
3419
3420 // Every function can be "readnone/argmemonly/inaccessiblememonly/...".
3421 getOrCreateAAFor<AAMemoryLocation>(FPos);
3422
3423 // Every function can track active assumptions.
3424 getOrCreateAAFor<AAAssumptionInfo>(FPos);
3425
3426 // If we're not using a dynamic mode for float, there's nothing worthwhile
3427 // to infer. This misses the edge case denormal-fp-math="dynamic" and
3428 // denormal-fp-math-f32=something, but that likely has no real world use.
3429 DenormalMode Mode = F.getDenormalMode(APFloat::IEEEsingle());
3430 if (Mode.Input == DenormalMode::Dynamic ||
3431 Mode.Output == DenormalMode::Dynamic)
3432 getOrCreateAAFor<AADenormalFPMath>(FPos);
3433
3434 // Return attributes are only appropriate if the return type is non void.
3435 Type *ReturnType = F.getReturnType();
3436 if (!ReturnType->isVoidTy()) {
3438 AttributeSet RetAttrs = Attrs.getRetAttrs();
3439
3440 // Every returned value might be dead.
3441 getOrCreateAAFor<AAIsDead>(RetPos);
3442
3443 // Every function might be simplified.
3444 bool UsedAssumedInformation = false;
3445 getAssumedSimplified(RetPos, nullptr, UsedAssumedInformation,
3447
3448 // Every returned value might be marked noundef.
3449 checkAndQueryIRAttr<Attribute::NoUndef, AANoUndef>(RetPos, RetAttrs);
3450
3451 if (ReturnType->isPointerTy()) {
3452
3453 // Every function with pointer return type might be marked align.
3454 getOrCreateAAFor<AAAlign>(RetPos);
3455
3456 // Every function with pointer return type might be marked nonnull.
3457 checkAndQueryIRAttr<Attribute::NonNull, AANonNull>(RetPos, RetAttrs);
3458
3459 // Every function with pointer return type might be marked noalias.
3460 checkAndQueryIRAttr<Attribute::NoAlias, AANoAlias>(RetPos, RetAttrs);
3461
3462 // Every function with pointer return type might be marked
3463 // dereferenceable.
3464 getOrCreateAAFor<AADereferenceable>(RetPos);
3465 } else if (AttributeFuncs::isNoFPClassCompatibleType(ReturnType)) {
3466 getOrCreateAAFor<AANoFPClass>(RetPos);
3467 }
3468 }
3469 }
3470
3471 for (Argument &Arg : F.args()) {
3472 IRPosition ArgPos = IRPosition::argument(Arg);
3473 auto ArgNo = Arg.getArgNo();
3474 AttributeSet ArgAttrs = Attrs.getParamAttrs(ArgNo);
3475
3476 if (!IsIPOAmendable) {
3477 if (Arg.getType()->isPointerTy())
3478 // Every argument with pointer type might be marked nofree.
3479 checkAndQueryIRAttr<Attribute::NoFree, AANoFree>(ArgPos, ArgAttrs);
3480 continue;
3481 }
3482
3483 // Every argument might be simplified. We have to go through the
3484 // Attributor interface though as outside AAs can register custom
3485 // simplification callbacks.
3486 bool UsedAssumedInformation = false;
3487 getAssumedSimplified(ArgPos, /* AA */ nullptr, UsedAssumedInformation,
3489
3490 // Every argument might be dead.
3491 getOrCreateAAFor<AAIsDead>(ArgPos);
3492
3493 // Every argument might be marked noundef.
3494 checkAndQueryIRAttr<Attribute::NoUndef, AANoUndef>(ArgPos, ArgAttrs);
3495
3496 if (Arg.getType()->isPointerTy()) {
3497 // Every argument with pointer type might be marked nonnull.
3498 checkAndQueryIRAttr<Attribute::NonNull, AANonNull>(ArgPos, ArgAttrs);
3499
3500 // Every argument with pointer type might be marked noalias.
3501 checkAndQueryIRAttr<Attribute::NoAlias, AANoAlias>(ArgPos, ArgAttrs);
3502
3503 // Every argument with pointer type might be marked dereferenceable.
3504 getOrCreateAAFor<AADereferenceable>(ArgPos);
3505
3506 // Every argument with pointer type might be marked align.
3507 getOrCreateAAFor<AAAlign>(ArgPos);
3508
3509 // Every argument with pointer type might be marked nocapture.
3510 checkAndQueryIRAttr<Attribute::NoCapture, AANoCapture>(ArgPos, ArgAttrs);
3511
3512 // Every argument with pointer type might be marked
3513 // "readnone/readonly/writeonly/..."
3514 getOrCreateAAFor<AAMemoryBehavior>(ArgPos);
3515
3516 // Every argument with pointer type might be marked nofree.
3517 checkAndQueryIRAttr<Attribute::NoFree, AANoFree>(ArgPos, ArgAttrs);
3518
3519 // Every argument with pointer type might be privatizable (or
3520 // promotable)
3521 getOrCreateAAFor<AAPrivatizablePtr>(ArgPos);
3522 } else if (AttributeFuncs::isNoFPClassCompatibleType(Arg.getType())) {
3523 getOrCreateAAFor<AANoFPClass>(ArgPos);
3524 }
3525 }
3526
3527 auto CallSitePred = [&](Instruction &I) -> bool {
3528 auto &CB = cast<CallBase>(I);
3529 IRPosition CBInstPos = IRPosition::inst(CB);
3531
3532 // Call sites might be dead if they do not have side effects and no live
3533 // users. The return value might be dead if there are no live users.
3534 getOrCreateAAFor<AAIsDead>(CBInstPos);
3535
3536 Function *Callee = dyn_cast_if_present<Function>(CB.getCalledOperand());
3537 // TODO: Even if the callee is not known now we might be able to simplify
3538 // the call/callee.
3539 if (!Callee) {
3540 getOrCreateAAFor<AAIndirectCallInfo>(CBFnPos);
3541 return true;
3542 }
3543
3544 // Every call site can track active assumptions.
3545 getOrCreateAAFor<AAAssumptionInfo>(CBFnPos);
3546
3547 // Skip declarations except if annotations on their call sites were
3548 // explicitly requested.
3549 if (!AnnotateDeclarationCallSites && Callee->isDeclaration() &&
3550 !Callee->hasMetadata(LLVMContext::MD_callback))
3551 return true;
3552
3553 if (!Callee->getReturnType()->isVoidTy() && !CB.use_empty()) {
3555 bool UsedAssumedInformation = false;
3556 getAssumedSimplified(CBRetPos, nullptr, UsedAssumedInformation,
3558
3559 if (AttributeFuncs::isNoFPClassCompatibleType(Callee->getReturnType()))
3560 getOrCreateAAFor<AANoFPClass>(CBInstPos);
3561 }
3562
3563 const AttributeList &CBAttrs = CBFnPos.getAttrList();
3564 for (int I = 0, E = CB.arg_size(); I < E; ++I) {
3565
3567 AttributeSet CBArgAttrs = CBAttrs.getParamAttrs(I);
3568
3569 // Every call site argument might be dead.
3570 getOrCreateAAFor<AAIsDead>(CBArgPos);
3571
3572 // Call site argument might be simplified. We have to go through the
3573 // Attributor interface though as outside AAs can register custom
3574 // simplification callbacks.
3575 bool UsedAssumedInformation = false;
3576 getAssumedSimplified(CBArgPos, /* AA */ nullptr, UsedAssumedInformation,
3578
3579 // Every call site argument might be marked "noundef".
3580 checkAndQueryIRAttr<Attribute::NoUndef, AANoUndef>(CBArgPos, CBArgAttrs);
3581
3582 Type *ArgTy = CB.getArgOperand(I)->getType();
3583
3584 if (!ArgTy->isPointerTy()) {
3586 getOrCreateAAFor<AANoFPClass>(CBArgPos);
3587
3588 continue;
3589 }
3590
3591 // Call site argument attribute "non-null".
3592 checkAndQueryIRAttr<Attribute::NonNull, AANonNull>(CBArgPos, CBArgAttrs);
3593
3594 // Call site argument attribute "nocapture".
3595 checkAndQueryIRAttr<Attribute::NoCapture, AANoCapture>(CBArgPos,
3596 CBArgAttrs);
3597
3598 // Call site argument attribute "no-alias".
3599 checkAndQueryIRAttr<Attribute::NoAlias, AANoAlias>(CBArgPos, CBArgAttrs);
3600
3601 // Call site argument attribute "dereferenceable".
3602 getOrCreateAAFor<AADereferenceable>(CBArgPos);
3603
3604 // Call site argument attribute "align".
3605 getOrCreateAAFor<AAAlign>(CBArgPos);
3606
3607 // Call site argument attribute
3608 // "readnone/readonly/writeonly/..."
3609 if (!CBAttrs.hasParamAttr(I, Attribute::ReadNone))
3610 getOrCreateAAFor<AAMemoryBehavior>(CBArgPos);
3611
3612 // Call site argument attribute "nofree".
3613 checkAndQueryIRAttr<Attribute::NoFree, AANoFree>(CBArgPos, CBArgAttrs);
3614 }
3615 return true;
3616 };
3617
3618 auto &OpcodeInstMap = InfoCache.getOpcodeInstMapForFunction(F);
3619 [[maybe_unused]] bool Success;
3620 bool UsedAssumedInformation = false;
3622 nullptr, OpcodeInstMap, CallSitePred, nullptr, nullptr,
3623 {(unsigned)Instruction::Invoke, (unsigned)Instruction::CallBr,
3624 (unsigned)Instruction::Call},
3625 UsedAssumedInformation);
3626 assert(Success && "Expected the check call to be successful!");
3627
3628 auto LoadStorePred = [&](Instruction &I) -> bool {
3629 if (auto *LI = dyn_cast<LoadInst>(&I)) {
3630 getOrCreateAAFor<AAAlign>(IRPosition::value(*LI->getPointerOperand()));
3631 if (SimplifyAllLoads)
3633 UsedAssumedInformation, AA::Intraprocedural);
3634 getOrCreateAAFor<AAAddressSpace>(
3635 IRPosition::value(*LI->getPointerOperand()));
3636 } else {
3637 auto &SI = cast<StoreInst>(I);
3638 getOrCreateAAFor<AAIsDead>(IRPosition::inst(I));
3639 getAssumedSimplified(IRPosition::value(*SI.getValueOperand()), nullptr,
3640 UsedAssumedInformation, AA::Intraprocedural);
3641 getOrCreateAAFor<AAAlign>(IRPosition::value(*SI.getPointerOperand()));
3642 getOrCreateAAFor<AAAddressSpace>(
3643 IRPosition::value(*SI.getPointerOperand()));
3644 }
3645 return true;
3646 };
3648 nullptr, OpcodeInstMap, LoadStorePred, nullptr, nullptr,
3649 {(unsigned)Instruction::Load, (unsigned)Instruction::Store},
3650 UsedAssumedInformation);
3651 assert(Success && "Expected the check call to be successful!");
3652
3653 // AllocaInstPredicate
3654 auto AAAllocationInfoPred = [&](Instruction &I) -> bool {
3655 getOrCreateAAFor<AAAllocationInfo>(IRPosition::value(I));
3656 return true;
3657 };
3658
3660 nullptr, OpcodeInstMap, AAAllocationInfoPred, nullptr, nullptr,
3661 {(unsigned)Instruction::Alloca}, UsedAssumedInformation);
3662 assert(Success && "Expected the check call to be successful!");
3663}
3664
3666 if (CloseWorldAssumption.getNumOccurrences())
3667 return CloseWorldAssumption;
3668 return isModulePass() && Configuration.IsClosedWorldModule;
3669}
3670
3671/// Helpers to ease debugging through output streams and print calls.
3672///
3673///{
3675 return OS << (S == ChangeStatus::CHANGED ? "changed" : "unchanged");
3676}
3677
3679 switch (AP) {
3681 return OS << "inv";
3683 return OS << "flt";
3685 return OS << "fn_ret";
3687 return OS << "cs_ret";
3689 return OS << "fn";
3691 return OS << "cs";
3693 return OS << "arg";
3695 return OS << "cs_arg";
3696 }
3697 llvm_unreachable("Unknown attribute position!");
3698}
3699
3701 const Value &AV = Pos.getAssociatedValue();
3702 OS << "{" << Pos.getPositionKind() << ":" << AV.getName() << " ["
3703 << Pos.getAnchorValue().getName() << "@" << Pos.getCallSiteArgNo() << "]";
3704
3705 if (Pos.hasCallBaseContext())
3706 OS << "[cb_context:" << *Pos.getCallBaseContext() << "]";
3707 return OS << "}";
3708}
3709
3711 OS << "range-state(" << S.getBitWidth() << ")<";
3712 S.getKnown().print(OS);
3713 OS << " / ";
3714 S.getAssumed().print(OS);
3715 OS << ">";
3716
3717 return OS << static_cast<const AbstractState &>(S);
3718}
3719
3721 return OS << (!S.isValidState() ? "top" : (S.isAtFixpoint() ? "fix" : ""));
3722}
3723
3725 AA.print(OS);
3726 return OS;
3727}
3728
3731 OS << "set-state(< {";
3732 if (!S.isValidState())
3733 OS << "full-set";
3734 else {
3735 for (const auto &It : S.getAssumedSet())
3736 OS << It << ", ";
3737 if (S.undefIsContained())
3738 OS << "undef ";
3739 }
3740 OS << "} >)";
3741
3742 return OS;
3743}
3744
3746 const PotentialLLVMValuesState &S) {
3747 OS << "set-state(< {";
3748 if (!S.isValidState())
3749 OS << "full-set";
3750 else {
3751 for (const auto &It : S.getAssumedSet()) {
3752 if (auto *F = dyn_cast<Function>(It.first.getValue()))
3753 OS << "@" << F->getName() << "[" << int(It.second) << "], ";
3754 else
3755 OS << *It.first.getValue() << "[" << int(It.second) << "], ";
3756 }
3757 if (S.undefIsContained())
3758 OS << "undef ";
3759 }
3760 OS << "} >)";
3761
3762 return OS;
3763}
3764
3766 OS << "[";
3767 OS << getName();
3768 OS << "] for CtxI ";
3769
3770 if (auto *I = getCtxI()) {
3771 OS << "'";
3772 I->print(OS);
3773 OS << "'";
3774 } else
3775 OS << "<<null inst>>";
3776
3777 OS << " at position " << getIRPosition() << " with state " << getAsStr(A)
3778 << '\n';
3779}
3780
3782 print(OS);
3783
3784 for (const auto &DepAA : Deps) {
3785 auto *AA = DepAA.getPointer();
3786 OS << " updates ";
3787 AA->print(OS);
3788 }
3789
3790 OS << '\n';
3791}
3792
3794 const AAPointerInfo::Access &Acc) {
3795 OS << " [" << Acc.getKind() << "] " << *Acc.getRemoteInst();
3796 if (Acc.getLocalInst() != Acc.getRemoteInst())
3797 OS << " via " << *Acc.getLocalInst();
3798 if (Acc.getContent()) {
3799 if (*Acc.getContent())
3800 OS << " [" << **Acc.getContent() << "]";
3801 else
3802 OS << " [ <unknown> ]";
3803 }
3804 return OS;
3805}
3806///}
3807
3808/// ----------------------------------------------------------------------------
3809/// Pass (Manager) Boilerplate
3810/// ----------------------------------------------------------------------------
3811
3813 SetVector<Function *> &Functions,
3814 AnalysisGetter &AG,
3815 CallGraphUpdater &CGUpdater,
3816 bool DeleteFns, bool IsModulePass) {
3817 if (Functions.empty())
3818 return false;
3819
3820 LLVM_DEBUG({
3821 dbgs() << "[Attributor] Run on module with " << Functions.size()
3822 << " functions:\n";
3823 for (Function *Fn : Functions)
3824 dbgs() << " - " << Fn->getName() << "\n";
3825 });
3826
3827 // Create an Attributor and initially empty information cache that is filled
3828 // while we identify default attribute opportunities.
3829 AttributorConfig AC(CGUpdater);
3830 AC.IsModulePass = IsModulePass;
3831 AC.DeleteFns = DeleteFns;
3832
3833 /// Tracking callback for specialization of indirect calls.
3835 IndirectCalleeTrackingMap;
3836 if (MaxSpecializationPerCB.getNumOccurrences()) {
3837 AC.IndirectCalleeSpecializationCallback =
3838 [&](Attributor &, const AbstractAttribute &AA, CallBase &CB,
3839 Function &Callee) {
3840 if (MaxSpecializationPerCB == 0)
3841 return false;
3842 auto &Set = IndirectCalleeTrackingMap[&CB];
3843 if (!Set)
3844 Set = std::make_unique<SmallPtrSet<Function *, 8>>();
3845 if (Set->size() >= MaxSpecializationPerCB)
3846 return Set->contains(&Callee);
3847 Set->insert(&Callee);
3848 return true;
3849 };
3850 }
3851
3852 Attributor A(Functions, InfoCache, AC);
3853
3854 // Create shallow wrappers for all functions that are not IPO amendable
3856 for (Function *F : Functions)
3857 if (!A.isFunctionIPOAmendable(*F))
3859
3860 // Internalize non-exact functions
3861 // TODO: for now we eagerly internalize functions without calculating the
3862 // cost, we need a cost interface to determine whether internalizing
3863 // a function is "beneficial"
3864 if (AllowDeepWrapper) {
3865 unsigned FunSize = Functions.size();
3866 for (unsigned u = 0; u < FunSize; u++) {
3867 Function *F = Functions[u];
3868 if (!F->isDeclaration() && !F->isDefinitionExact() && F->getNumUses() &&
3869 !GlobalValue::isInterposableLinkage(F->getLinkage())) {
3871 assert(NewF && "Could not internalize function.");
3872 Functions.insert(NewF);
3873
3874 // Update call graph
3875 CGUpdater.replaceFunctionWith(*F, *NewF);
3876 for (const Use &U : NewF->uses())
3877 if (CallBase *CB = dyn_cast<CallBase>(U.getUser())) {
3878 auto *CallerF = CB->getCaller();
3879 CGUpdater.reanalyzeFunction(*CallerF);
3880 }
3881 }
3882 }
3883 }
3884
3885 for (Function *F : Functions) {
3886 if (F->hasExactDefinition())
3887 NumFnWithExactDefinition++;
3888 else
3889 NumFnWithoutExactDefinition++;
3890
3891 // We look at internal functions only on-demand but if any use is not a
3892 // direct call or outside the current set of analyzed functions, we have
3893 // to do it eagerly.
3894 if (F->hasLocalLinkage()) {
3895 if (llvm::all_of(F->uses(), [&Functions](const Use &U) {
3896 const auto *CB = dyn_cast<CallBase>(U.getUser());
3897 return CB && CB->isCallee(&U) &&
3898 Functions.count(const_cast<Function *>(CB->getCaller()));
3899 }))
3900 continue;
3901 }
3902
3903 // Populate the Attributor with abstract attribute opportunities in the
3904 // function and the information cache with IR information.
3905 A.identifyDefaultAbstractAttributes(*F);
3906 }
3907
3908 ChangeStatus Changed = A.run();
3909
3910 LLVM_DEBUG(dbgs() << "[Attributor] Done with " << Functions.size()
3911 << " functions, result: " << Changed << ".\n");
3912 return Changed == ChangeStatus::CHANGED;
3913}
3914
3916 SetVector<Function *> &Functions,
3917 AnalysisGetter &AG,
3918 CallGraphUpdater &CGUpdater,
3920 bool IsModulePass) {
3921 if (Functions.empty())
3922 return false;
3923
3924 LLVM_DEBUG({
3925 dbgs() << "[AttributorLight] Run on module with " << Functions.size()
3926 << " functions:\n";
3927 for (Function *Fn : Functions)
3928 dbgs() << " - " << Fn->getName() << "\n";
3929 });
3930
3931 // Create an Attributor and initially empty information cache that is filled
3932 // while we identify default attribute opportunities.
3933 AttributorConfig AC(CGUpdater);
3934 AC.IsModulePass = IsModulePass;
3935 AC.DeleteFns = false;
3936 DenseSet<const char *> Allowed(
3942 AC.Allowed = &Allowed;
3943 AC.UseLiveness = false;
3944
3945 Attributor A(Functions, InfoCache, AC);
3946
3947 for (Function *F : Functions) {
3948 if (F->hasExactDefinition())
3949 NumFnWithExactDefinition++;
3950 else
3951 NumFnWithoutExactDefinition++;
3952
3953 // We look at internal functions only on-demand but if any use is not a
3954 // direct call or outside the current set of analyzed functions, we have
3955 // to do it eagerly.
3956 if (AC.UseLiveness && F->hasLocalLinkage()) {
3957 if (llvm::all_of(F->uses(), [&Functions](const Use &U) {
3958 const auto *CB = dyn_cast<CallBase>(U.getUser());
3959 return CB && CB->isCallee(&U) &&
3960 Functions.count(const_cast<Function *>(CB->getCaller()));
3961 }))
3962 continue;
3963 }
3964
3965 // Populate the Attributor with abstract attribute opportunities in the
3966 // function and the information cache with IR information.
3967 A.identifyDefaultAbstractAttributes(*F);
3968 }
3969
3970 ChangeStatus Changed = A.run();
3971
3972 if (Changed == ChangeStatus::CHANGED) {
3973 // Invalidate analyses for modified functions so that we don't have to
3974 // invalidate all analyses for all functions in this SCC.
3975 PreservedAnalyses FuncPA;
3976 // We haven't changed the CFG for modified functions.
3977 FuncPA.preserveSet<CFGAnalyses>();
3978 for (Function *Changed : A.getModifiedFunctions()) {
3979 FAM.invalidate(*Changed, FuncPA);
3980 // Also invalidate any direct callers of changed functions since analyses
3981 // may care about attributes of direct callees. For example, MemorySSA
3982 // cares about whether or not a call's callee modifies memory and queries
3983 // that through function attributes.
3984 for (auto *U : Changed->users()) {
3985 if (auto *Call = dyn_cast<CallBase>(U)) {
3986 if (Call->getCalledFunction() == Changed)
3987 FAM.invalidate(*Call->getFunction(), FuncPA);
3988 }
3989 }
3990 }
3991 }
3992 LLVM_DEBUG(dbgs() << "[Attributor] Done with " << Functions.size()
3993 << " functions, result: " << Changed << ".\n");
3994 return Changed == ChangeStatus::CHANGED;
3995}
3996
3997void AADepGraph::viewGraph() { llvm::ViewGraph(this, "Dependency Graph"); }
3998
4000 static std::atomic<int> CallTimes;
4001 std::string Prefix;
4002
4003 if (!DepGraphDotFileNamePrefix.empty())
4005 else
4006 Prefix = "dep_graph";
4007 std::string Filename =
4008 Prefix + "_" + std::to_string(CallTimes.load()) + ".dot";
4009
4010 outs() << "Dependency graph dump to " << Filename << ".\n";
4011
4012 std::error_code EC;
4013
4014 raw_fd_ostream File(Filename, EC, sys::fs::OF_TextWithCRLF);
4015 if (!EC)
4016 llvm::WriteGraph(File, this);
4017
4018 CallTimes++;
4019}
4020
4022 for (auto DepAA : SyntheticRoot.Deps)
4023 cast<AbstractAttribute>(DepAA.getPointer())->printWithDeps(outs());
4024}
4025
4029 AnalysisGetter AG(FAM);
4030
4031 SetVector<Function *> Functions;
4032 for (Function &F : M)
4033 Functions.insert(&F);
4034
4035 CallGraphUpdater CGUpdater;
4037 InformationCache InfoCache(M, AG, Allocator, /* CGSCC */ nullptr);
4038 if (runAttributorOnFunctions(InfoCache, Functions, AG, CGUpdater,
4039 /* DeleteFns */ true, /* IsModulePass */ true)) {
4040 // FIXME: Think about passes we will preserve and add them here.
4041 return PreservedAnalyses::none();
4042 }
4043 return PreservedAnalyses::all();
4044}
4045
4048 LazyCallGraph &CG,
4049 CGSCCUpdateResult &UR) {
4051 AM.getResult<FunctionAnalysisManagerCGSCCProxy>(C, CG).getManager();
4052 AnalysisGetter AG(FAM);
4053
4054 SetVector<Function *> Functions;
4055 for (LazyCallGraph::Node &N : C)
4056 Functions.insert(&N.getFunction());
4057
4058 if (Functions.empty())
4059 return PreservedAnalyses::all();
4060
4061 Module &M = *Functions.back()->getParent();
4062 CallGraphUpdater CGUpdater;
4063 CGUpdater.initialize(CG, C, AM, UR);
4065 InformationCache InfoCache(M, AG, Allocator, /* CGSCC */ &Functions);
4066 if (runAttributorOnFunctions(InfoCache, Functions, AG, CGUpdater,
4067 /* DeleteFns */ false,
4068 /* IsModulePass */ false)) {
4069 // FIXME: Think about passes we will preserve and add them here.
4072 return PA;
4073 }
4074 return PreservedAnalyses::all();
4075}
4076
4081 AnalysisGetter AG(FAM, /* CachedOnly */ true);
4082
4083 SetVector<Function *> Functions;
4084 for (Function &F : M)
4085 Functions.insert(&F);
4086
4087 CallGraphUpdater CGUpdater;
4089 InformationCache InfoCache(M, AG, Allocator, /* CGSCC */ nullptr);
4090 if (runAttributorLightOnFunctions(InfoCache, Functions, AG, CGUpdater, FAM,
4091 /* IsModulePass */ true)) {
4093 // We have not added or removed functions.
4095 // We already invalidated all relevant function analyses above.
4097 return PA;
4098 }
4099 return PreservedAnalyses::all();
4100}
4101
4104 LazyCallGraph &CG,
4105 CGSCCUpdateResult &UR) {
4107 AM.getResult<FunctionAnalysisManagerCGSCCProxy>(C, CG).getManager();
4108 AnalysisGetter AG(FAM);
4109
4110 SetVector<Function *> Functions;
4111 for (LazyCallGraph::Node &N : C)
4112 Functions.insert(&N.getFunction());
4113
4114 if (Functions.empty())
4115 return PreservedAnalyses::all();
4116
4117 Module &M = *Functions.back()->getParent();
4118 CallGraphUpdater CGUpdater;
4119 CGUpdater.initialize(CG, C, AM, UR);
4121 InformationCache InfoCache(M, AG, Allocator, /* CGSCC */ &Functions);
4122 if (runAttributorLightOnFunctions(InfoCache, Functions, AG, CGUpdater, FAM,
4123 /* IsModulePass */ false)) {
4125 // We have not added or removed functions.
4127 // We already invalidated all relevant function analyses above.
4129 return PA;
4130 }
4131 return PreservedAnalyses::all();
4132}
4133namespace llvm {
4134
4135template <> struct GraphTraits<AADepGraphNode *> {
4139
4140 static NodeRef getEntryNode(AADepGraphNode *DGN) { return DGN; }
4141 static NodeRef DepGetVal(const DepTy &DT) { return DT.getPointer(); }
4142
4146
4147 static ChildIteratorType child_begin(NodeRef N) { return N->child_begin(); }
4148
4149 static ChildIteratorType child_end(NodeRef N) { return N->child_end(); }
4150};
4151
4152template <>
4154 static NodeRef getEntryNode(AADepGraph *DG) { return DG->GetEntryNode(); }
4155
4158
4159 static nodes_iterator nodes_begin(AADepGraph *DG) { return DG->begin(); }
4160
4161 static nodes_iterator nodes_end(AADepGraph *DG) { return DG->end(); }
4162};
4163
4164template <> struct DOTGraphTraits<AADepGraph *> : public DefaultDOTGraphTraits {
4166
4167 static std::string getNodeLabel(const AADepGraphNode *Node,
4168 const AADepGraph *DG) {
4169 std::string AAString;
4170 raw_string_ostream O(AAString);
4171 Node->print(O);
4172 return AAString;
4173 }
4174};
4175
4176} // end namespace llvm
#define Success
amdgpu aa AMDGPU Address space based Alias Analysis Wrapper
Rewrite undef for PHI
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL
Expand Atomic instructions
This file contains the simple types necessary to represent the attributes associated with functions a...
static cl::opt< bool > AllowShallowWrappers("attributor-allow-shallow-wrappers", cl::Hidden, cl::desc("Allow the Attributor to create shallow " "wrappers for non-exact definitions."), cl::init(false))
bool canMarkAsVisited(const User *Usr)
#define VERBOSE_DEBUG_TYPE
Definition: Attributor.cpp:67
static cl::opt< bool > EnableHeapToStack("enable-heap-to-stack-conversion", cl::init(true), cl::Hidden)
static cl::list< std::string > SeedAllowList("attributor-seed-allow-list", cl::Hidden, cl::desc("Comma separated list of attribute names that are " "allowed to be seeded."), cl::CommaSeparated)
static bool runAttributorOnFunctions(InformationCache &InfoCache, SetVector< Function * > &Functions, AnalysisGetter &AG, CallGraphUpdater &CGUpdater, bool DeleteFns, bool IsModulePass)
}
static bool isPotentiallyReachable(Attributor &A, const Instruction &FromI, const Instruction *ToI, const Function &ToFn, const AbstractAttribute &QueryingAA, const AA::InstExclusionSetTy *ExclusionSet, std::function< bool(const Function &F)> GoBackwardsCB)
Definition: Attributor.cpp:661
static bool getPotentialCopiesOfMemoryValue(Attributor &A, Ty &I, SmallSetVector< Value *, 4 > &PotentialCopies, SmallSetVector< Instruction *, 4 > *PotentialValueOrigins, const AbstractAttribute &QueryingAA, bool &UsedAssumedInformation, bool OnlyExact)
Definition: Attributor.cpp:365
static bool runAttributorLightOnFunctions(InformationCache &InfoCache, SetVector< Function * > &Functions, AnalysisGetter &AG, CallGraphUpdater &CGUpdater, FunctionAnalysisManager &FAM, bool IsModulePass)
static cl::opt< unsigned, true > MaxInitializationChainLengthX("attributor-max-initialization-chain-length", cl::Hidden, cl::desc("Maximal number of chained initializations (to avoid stack overflows)"), cl::location(MaxInitializationChainLength), cl::init(1024))
static cl::opt< unsigned > MaxSpecializationPerCB("attributor-max-specializations-per-call-base", cl::Hidden, cl::desc("Maximal number of callees specialized for " "a call base"), cl::init(UINT32_MAX))
static cl::opt< bool > SimplifyAllLoads("attributor-simplify-all-loads", cl::Hidden, cl::desc("Try to simplify all loads."), cl::init(true))
static bool addIfNotExistent(LLVMContext &Ctx, const Attribute &Attr, AttributeSet AttrSet, bool ForceReplace, AttrBuilder &AB)
Return true if the information provided by Attr was added to the attribute set AttrSet.
Definition: Attributor.cpp:956
static cl::opt< bool > ViewDepGraph("attributor-view-dep-graph", cl::Hidden, cl::desc("View the dependency graph."), cl::init(false))
static bool isEqualOrWorse(const Attribute &New, const Attribute &Old)
Return true if New is equal or worse than Old.
Definition: Attributor.cpp:946
static cl::opt< bool > AllowDeepWrapper("attributor-allow-deep-wrappers", cl::Hidden, cl::desc("Allow the Attributor to use IP information " "derived from non-exact functions via cloning"), cl::init(false))
static cl::opt< bool > DumpDepGraph("attributor-dump-dep-graph", cl::Hidden, cl::desc("Dump the dependency graph to dot files."), cl::init(false))
static cl::opt< bool > PrintCallGraph("attributor-print-call-graph", cl::Hidden, cl::desc("Print Attributor's internal call graph"), cl::init(false))
static bool checkForAllInstructionsImpl(Attributor *A, InformationCache::OpcodeInstMapTy &OpcodeInstMap, function_ref< bool(Instruction &)> Pred, const AbstractAttribute *QueryingAA, const AAIsDead *LivenessAA, ArrayRef< unsigned > Opcodes, bool &UsedAssumedInformation, bool CheckBBLivenessOnly=false, bool CheckPotentiallyDead=false)
static cl::opt< bool > PrintDependencies("attributor-print-dep", cl::Hidden, cl::desc("Print attribute dependencies"), cl::init(false))
static bool isAssumedReadOnlyOrReadNone(Attributor &A, const IRPosition &IRP, const AbstractAttribute &QueryingAA, bool RequireReadNone, bool &IsKnown)
Definition: Attributor.cpp:609
static cl::opt< std::string > DepGraphDotFileNamePrefix("attributor-depgraph-dot-filename-prefix", cl::Hidden, cl::desc("The prefix used for the CallGraph dot file names."))
static cl::opt< bool > AnnotateDeclarationCallSites("attributor-annotate-decl-cs", cl::Hidden, cl::desc("Annotate call sites of function declarations."), cl::init(false))
static cl::opt< unsigned > SetFixpointIterations("attributor-max-iterations", cl::Hidden, cl::desc("Maximal number of fixpoint iterations."), cl::init(32))
static cl::list< std::string > FunctionSeedAllowList("attributor-function-seed-allow-list", cl::Hidden, cl::desc("Comma separated list of function names that are " "allowed to be seeded."), cl::CommaSeparated)
static cl::opt< bool > EnableCallSiteSpecific("attributor-enable-call-site-specific-deduction", cl::Hidden, cl::desc("Allow the Attributor to do call site specific analysis"), cl::init(false))
static cl::opt< bool > CloseWorldAssumption("attributor-assume-closed-world", cl::Hidden, cl::desc("Should a closed world be assumed, or not. Default if not set."))
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< ErlangGC > A("erlang", "erlang-compatible garbage collector")
This file provides interfaces used to build and manipulate a call graph, which is a very useful tool ...
This file contains the declarations for the subclasses of Constant, which represent the different fla...
return RetTy
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
This file provides an implementation of debug counters.
#define DEBUG_COUNTER(VARNAME, COUNTERNAME, DESC)
Definition: DebugCounter.h:190
#define LLVM_DEBUG(X)
Definition: Debug.h:101
#define DEBUG_WITH_TYPE(TYPE, X)
DEBUG_WITH_TYPE macro - This macro should be used by passes to emit debug information.
Definition: Debug.h:64
static Function * getFunction(Constant *C)
Definition: Evaluator.cpp:236
Rewrite Partial Register Uses
IRTranslator LLVM IR MI
#define F(x, y, z)
Definition: MD5.cpp:55
#define I(x, y, z)
Definition: MD5.cpp:58
Contains a collection of routines for determining if a given instruction is guaranteed to execute if ...
ConstantRange Range(APInt(BitWidth, Low), APInt(BitWidth, High))
uint64_t IntrinsicInst * II
FunctionAnalysisManager FAM
This file defines the PointerIntPair class.
static StringRef getName(Value *V)
Basic Register Allocator
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static bool isSimple(Instruction *I)
This file contains some templates that are useful if you are working with the STL at all.
raw_pwrite_stream & OS
This file defines the SmallPtrSet class.
This file defines the 'Statistic' class, which is designed to be an easy way to expose various metric...
#define STATISTIC(VARNAME, DESC)
Definition: Statistic.h:167
Class for arbitrary precision integers.
Definition: APInt.h:78
AbstractCallSite.
CallBase * getInstruction() const
Return the underlying instruction.
bool isCallbackCall() const
Return true if this ACS represents a callback call.
const Use & getCalleeUseForCallback() const
Return the use of the callee value in the underlying instruction.
static void getCallbackUses(const CallBase &CB, SmallVectorImpl< const Use * > &CallbackUses)
Add operand uses of CB that represent callback uses into CallbackUses.
bool isCallee(Value::const_user_iterator UI) const
Return true if UI is the use that defines the callee of this ACS.
Value * getCallArgOperand(Argument &Arg) const
Return the operand of the underlying instruction associated with Arg.
int getCallArgOperandNo(Argument &Arg) const
Return the operand index of the underlying instruction associated with Arg.
unsigned getNumArgOperands() const
Return the number of parameters of the callee.
Function * getCalledFunction() const
Return the function being called if this is a direct call, otherwise return null (if it's an indirect...
This templated class represents "all analyses that operate over <a particular IR unit>" (e....
Definition: Analysis.h:49
A container for analyses that lazily runs them and caches their results.
Definition: PassManager.h:253
void invalidate(IRUnitT &IR, const PreservedAnalyses &PA)
Invalidate cached analyses for an IR unit.
PassT::Result & getResult(IRUnitT &IR, ExtraArgTs... ExtraArgs)
Get the result of an analysis pass for a given IR unit.
Definition: PassManager.h:405
This class represents an incoming formal argument to a Function.
Definition: Argument.h:31
const Function * getParent() const
Definition: Argument.h:43
unsigned getArgNo() const
Return the index of this formal argument in its containing function.
Definition: Argument.h:49
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:165
bool empty() const
empty - Check if the array is empty.
Definition: ArrayRef.h:160
AttributeSet getFnAttrs() const
The function attributes are returned.
static AttributeList get(LLVMContext &C, ArrayRef< std::pair< unsigned, Attribute > > Attrs)
Create an AttributeList with the specified parameters in it.
AttributeSet getRetAttrs() const
The attributes for the ret value are returned.
bool hasAttrSomewhere(Attribute::AttrKind Kind, unsigned *Index=nullptr) const
Return true if the specified attribute is set for at least one parameter or for the return value.
bool hasParamAttr(unsigned ArgNo, Attribute::AttrKind Kind) const
Return true if the attribute exists for the given argument.
Definition: Attributes.h:805
AttributeSet getParamAttrs(unsigned ArgNo) const
The attributes for the argument or parameter at the given index are returned.
MemoryEffects getMemoryEffects() const
Definition: Attributes.cpp:988
bool hasAttribute(Attribute::AttrKind Kind) const
Return true if the attribute exists in this set.
Definition: Attributes.cpp:909
Attribute getAttribute(Attribute::AttrKind Kind) const
Return the attribute object.
Definition: Attributes.cpp:917
bool isStringAttribute() const
Return true if the attribute is a string (target-dependent) attribute.
Definition: Attributes.cpp:346
bool isEnumAttribute() const
Return true if the attribute is an Attribute::AttrKind type.
Definition: Attributes.cpp:338
bool isIntAttribute() const
Return true if the attribute is an integer attribute.
Definition: Attributes.cpp:342
uint64_t getValueAsInt() const
Return the attribute's value as an integer.
Definition: Attributes.cpp:370
StringRef getKindAsString() const
Return the attribute's kind as a string.
Definition: Attributes.cpp:384
static Attribute get(LLVMContext &Context, AttrKind Kind, uint64_t Val=0)
Return a uniquified Attribute object.
Definition: Attributes.cpp:94
Attribute::AttrKind getKindAsEnum() const
Return the attribute's kind as an enum (Attribute::AttrKind).
Definition: Attributes.cpp:362
MemoryEffects getMemoryEffects() const
Returns memory effects.
Definition: Attributes.cpp:483
StringRef getValueAsString() const
Return the attribute's value as a string.
Definition: Attributes.cpp:391
AttrKind
This enumeration lists the attributes that can be associated with parameters, function results,...
Definition: Attributes.h:86
@ None
No attributes have been set.
Definition: Attributes.h:88
LLVM Basic Block Representation.
Definition: BasicBlock.h:61
const Instruction & front() const
Definition: BasicBlock.h:461
static BasicBlock * Create(LLVMContext &Context, const Twine &Name="", Function *Parent=nullptr, BasicBlock *InsertBefore=nullptr)
Creates a new BasicBlock.
Definition: BasicBlock.h:202
const BasicBlock * getUniquePredecessor() const
Return the predecessor of this block if it has a unique predecessor block.
Definition: BasicBlock.cpp:465
const Function * getParent() const
Return the enclosing method, or null if none.
Definition: BasicBlock.h:209
const Instruction * getTerminator() const LLVM_READONLY
Returns the terminator instruction if the block is well formed or null if the block is not well forme...
Definition: BasicBlock.h:229
static BlockAddress * get(Function *F, BasicBlock *BB)
Return a BlockAddress for the specified function and basic block.
Definition: Constants.cpp:1871
Allocate memory in an ever growing pool, as if by bump-pointer.
Definition: Allocator.h:66
Represents analyses that only rely on functions' control flow.
Definition: Analysis.h:72
Base class for all callable instructions (InvokeInst and CallInst) Holds everything related to callin...
Definition: InstrTypes.h:1236
void setCallingConv(CallingConv::ID CC)
Definition: InstrTypes.h:1527
void addFnAttr(Attribute::AttrKind Kind)
Adds the attribute to the function.
Definition: InstrTypes.h:1574
void getOperandBundlesAsDefs(SmallVectorImpl< OperandBundleDef > &Defs) const
Return the list of operand bundles attached to this instruction as a vector of OperandBundleDefs.
CallingConv::ID getCallingConv() const
Definition: InstrTypes.h:1523
bool isMustTailCall() const
Tests if this call site must be tail call optimized.
Value * getCalledOperand() const
Definition: InstrTypes.h:1458
void setAttributes(AttributeList A)
Set the parameter attributes for this call.
Definition: InstrTypes.h:1546
unsigned arg_size() const
Definition: InstrTypes.h:1408
AttributeList getAttributes() const
Return the parameter attributes for this call.
Definition: InstrTypes.h:1542
Function * getCaller()
Helper to get the caller (the parent function).
Wrapper to unify "old style" CallGraph and "new style" LazyCallGraph.
void removeFunction(Function &Fn)
Remove Fn from the call graph.
void replaceFunctionWith(Function &OldFn, Function &NewFn)
Replace OldFn in the call graph (and SCC) with NewFn.
void reanalyzeFunction(Function &Fn)
After an CGSCC pass changes a function in ways that affect the call graph, this method can be called ...
void initialize(LazyCallGraph &LCG, LazyCallGraph::SCC &SCC, CGSCCAnalysisManager &AM, CGSCCUpdateResult &UR)
Initializers for usage outside of a CGSCC pass, inside a CGSCC pass in the old and new pass manager (...
This class represents a function call, abstracting a target machine's calling convention.
static CallInst * Create(FunctionType *Ty, Value *F, const Twine &NameStr="", InsertPosition InsertBefore=nullptr)
void setTailCall(bool IsTc=true)
A constant value that is initialized with an expression using other constant values.
Definition: Constants.h:1084
static Constant * getPointerCast(Constant *C, Type *Ty)
Create a BitCast, AddrSpaceCast, or a PtrToInt cast constant expression.
Definition: Constants.cpp:2215
static Constant * getTrunc(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:2241
void print(raw_ostream &OS) const
Print out the bounds to a stream.
This is an important base class in LLVM.
Definition: Constant.h:42
static Constant * getNullValue(Type *Ty)
Constructor to create a '0' constant of arbitrary type.
Definition: Constants.cpp:370
This class represents an Operation in the Expression.
A parsed version of the target data layout string in and methods for querying it.
Definition: DataLayout.h:110
static bool shouldExecute(unsigned CounterName)
Definition: DebugCounter.h:87
ValueT lookup(const_arg_type_t< KeyT > Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: DenseMap.h:202
bool empty() const
Definition: DenseMap.h:98
bool contains(const_arg_type_t< KeyT > Val) const
Return true if the specified key is in the map, false otherwise.
Definition: DenseMap.h:145
Implements a dense probed hash-table based set.
Definition: DenseSet.h:271
Analysis pass which computes a DominatorTree.
Definition: Dominators.h:279
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree.
Definition: Dominators.h:162
A proxy from a FunctionAnalysisManager to an SCC.
Class to represent function types.
Definition: DerivedTypes.h:103
static FunctionType * get(Type *Result, ArrayRef< Type * > Params, bool isVarArg)
This static method is the primary way of constructing a FunctionType.
void setSubprogram(DISubprogram *SP)
Set the attached subprogram.
Definition: Metadata.cpp:1826
static Function * Create(FunctionType *Ty, LinkageTypes Linkage, unsigned AddrSpace, const Twine &N="", Module *M=nullptr)
Definition: Function.h:165
void splice(Function::iterator ToIt, Function *FromF)
Transfer all blocks from FromF to this function at ToIt.
Definition: Function.h:752
const BasicBlock & getEntryBlock() const
Definition: Function.h:800
FunctionType * getFunctionType() const
Returns the FunctionType for me.
Definition: Function.h:207
iterator_range< arg_iterator > args()
Definition: Function.h:855
DISubprogram * getSubprogram() const
Get the attached subprogram.
Definition: Metadata.cpp:1830
MemoryEffects getMemoryEffects() const
Definition: Function.cpp:855
bool hasParamAttribute(unsigned ArgNo, Attribute::AttrKind Kind) const
check if an attributes is in the list of attributes.
Definition: Function.cpp:731
bool IsNewDbgInfoFormat
Is this function using intrinsics to record the position of debugging information,...
Definition: Function.h:108
AttributeList getAttributes() const
Return the attribute list for this Function.
Definition: Function.h:350
iterator begin()
Definition: Function.h:816
arg_iterator arg_begin()
Definition: Function.h:831
void setAttributes(AttributeList Attrs)
Set the attribute list for this Function.
Definition: Function.h:353
LLVMContext & getContext() const
getContext - Return a reference to the LLVMContext associated with this function.
Definition: Function.cpp:358
size_t arg_size() const
Definition: Function.h:864
Type * getReturnType() const
Returns the type of the ret val.
Definition: Function.h:212
void setMemoryEffects(MemoryEffects ME)
Definition: Function.cpp:858
Argument * getArg(unsigned i) const
Definition: Function.h:849
bool isVarArg() const
isVarArg - Return true if this function takes a variable number of arguments.
Definition: Function.h:225
bool hasFnAttribute(Attribute::AttrKind Kind) const
Return true if the function has the attribute.
Definition: Function.cpp:719
void copyAttributesFrom(const Function *Src)
copyAttributesFrom - copy all additional attributes (those not needed to create a Function) from the ...
Definition: Function.cpp:839
bool hasMetadata() const
Return true if this value has any metadata attached to it.
Definition: Value.h:589
void addMetadata(unsigned KindID, MDNode &MD)
Add a metadata attachment.
Definition: Metadata.cpp:1521
bool isDeclaration() const
Return true if the primary definition of this global value is outside of the current translation unit...
Definition: Globals.cpp:290
LinkageTypes getLinkage() const
Definition: GlobalValue.h:546
bool hasLocalLinkage() const
Definition: GlobalValue.h:528
void setLinkage(LinkageTypes LT)
Definition: GlobalValue.h:537
unsigned getAddressSpace() const
Definition: GlobalValue.h:205
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:656
void setDSOLocal(bool Local)
Definition: GlobalValue.h:303
PointerType * getType() const
Global values are always pointers.
Definition: GlobalValue.h:294
@ DefaultVisibility
The GV is visible.
Definition: GlobalValue.h:67
void setVisibility(VisibilityTypes V)
Definition: GlobalValue.h:254
static bool isInterposableLinkage(LinkageTypes Linkage)
Whether the definition of this global may be replaced by something non-equivalent at link time.
Definition: GlobalValue.h:425
@ PrivateLinkage
Like Internal, but omit from symbol table.
Definition: GlobalValue.h:60
@ InternalLinkage
Rename collisions when linking (static functions).
Definition: GlobalValue.h:59
bool isSuccess() const
Definition: InlineCost.h:189
An analysis over an "outer" IR unit that provides access to an analysis manager over an "inner" IR un...
Definition: PassManager.h:563
InstListType::iterator eraseFromParent()
This method unlinks 'this' from the containing basic block and deletes it.
Definition: Instruction.cpp:92
const Function * getFunction() const
Return the function this instruction belongs to.
Definition: Instruction.cpp:70
const Instruction * getNextNonDebugInstruction(bool SkipPseudoOp=false) const
Return a pointer to the next non-debug instruction in the same basic block as 'this',...
void copyMetadata(const Instruction &SrcInst, ArrayRef< unsigned > WL=ArrayRef< unsigned >())
Copy metadata from SrcInst to this instruction.
Invoke instruction.
static InvokeInst * Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal, BasicBlock *IfException, ArrayRef< Value * > Args, const Twine &NameStr, InsertPosition InsertBefore=nullptr)
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:67
A node in the call graph.
An SCC of the call graph.
A lazily constructed view of the call graph of a module.
An instruction for reading from memory.
Definition: Instructions.h:174
This is the common base class for memset/memcpy/memmove.
This class wraps the llvm.memcpy/memmove intrinsics.
static MemoryEffectsBase argMemOnly(ModRefInfo MR=ModRefInfo::ModRef)
Create MemoryEffectsBase that can only access argument memory.
Definition: ModRef.h:132
bool doesAccessArgPointees() const
Whether this function may access argument memory.
Definition: ModRef.h:206
static MemoryLocation getForSource(const MemTransferInst *MTI)
Return a location representing the source of a memory transfer.
static MemoryLocation getForDest(const MemIntrinsic *MI)
Return a location representing the destination of a memory set or transfer.
static std::optional< MemoryLocation > getOrNone(const Instruction *Inst)
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:65
const FunctionListType & getFunctionList() const
Get the Module's list of functions (constant).
Definition: Module.h:613
Diagnostic information for missed-optimization remarks.
PointerIntPair - This class implements a pair of a pointer and small integer.
void * getOpaqueValue() const
PointerTy getPointer() const
static PoisonValue * get(Type *T)
Static factory methods - Return an 'poison' object of the specified type.
Definition: Constants.cpp:1852
A set of analyses that are preserved following a run of a transformation pass.
Definition: Analysis.h:111
static PreservedAnalyses none()
Convenience factory function for the empty preserved set.
Definition: Analysis.h:114
static PreservedAnalyses all()
Construct a special preserved set that preserves all passes.
Definition: Analysis.h:117
void preserveSet()
Mark an analysis set as preserved.
Definition: Analysis.h:146
void preserve()
Mark an analysis as preserved.
Definition: Analysis.h:131
Return a value (possibly void), from a function.
static ReturnInst * Create(LLVMContext &C, Value *retVal=nullptr, InsertPosition InsertBefore=nullptr)
A vector that has set insertion semantics.
Definition: SetVector.h:57
ArrayRef< value_type > getArrayRef() const
Definition: SetVector.h:84
bool remove(const value_type &X)
Remove an item from the set vector.
Definition: SetVector.h:188
size_type size() const
Determine the number of elements in the SetVector.
Definition: SetVector.h:98
const value_type & front() const
Return the first element of the SetVector.
Definition: SetVector.h:143
const value_type & back() const
Return the last element of the SetVector.
Definition: SetVector.h:149
typename vector_type::const_iterator iterator
Definition: SetVector.h:69
iterator end()
Get an iterator to the end of the SetVector.
Definition: SetVector.h:113
void clear()
Completely clear the SetVector.
Definition: SetVector.h:273
size_type count(const key_type &key) const
Count the number of elements of a given key in the SetVector.
Definition: SetVector.h:264
bool empty() const
Determine if the SetVector is empty or not.
Definition: SetVector.h:93
iterator begin()
Get an iterator to the beginning of the SetVector.
Definition: SetVector.h:103
bool insert(const value_type &X)
Insert a new element into the SetVector.
Definition: SetVector.h:162
size_type size() const
Definition: SmallPtrSet.h:94
A templated base class for SmallPtrSet which provides the typesafe interface that is common across al...
Definition: SmallPtrSet.h:323
size_type count(ConstPtrType Ptr) const
count - Return 1 if the specified pointer is in the set, 0 otherwise.
Definition: SmallPtrSet.h:412
std::pair< iterator, bool > insert(PtrType Ptr)
Inserts Ptr if and only if there is no element in the container equal to Ptr.
Definition: SmallPtrSet.h:344
A SetVector that performs no allocations if smaller than a certain size.
Definition: SetVector.h:370
bool empty() const
Definition: SmallVector.h:94
size_t size() const
Definition: SmallVector.h:91
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: SmallVector.h:586
void reserve(size_type N)
Definition: SmallVector.h:676
void append(ItTy in_start, ItTy in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:696
void resize(size_type N)
Definition: SmallVector.h:651
void push_back(const T &Elt)
Definition: SmallVector.h:426
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1209
An instruction for storing to memory.
Definition: Instructions.h:290
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
A visitor class for IR positions.
Definition: Attributor.h:1111
SubsumingPositionIterator(const IRPosition &IRP)
Provides information about what library functions are available for the current target.
The TimeTraceScope is a helper class to call the begin and end functions of the time trace profiler.
Definition: TimeProfiler.h:147
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:44
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
bool isPointerTy() const
True if this is an instance of PointerType.
Definition: Type.h:255
unsigned getPointerAddressSpace() const
Get the address space of this pointer or pointer vector type.
bool isFloatingPointTy() const
Return true if this is one of the floating-point types.
Definition: Type.h:185
bool isIntegerTy() const
True if this is an instance of IntegerType.
Definition: Type.h:228
TypeSize getPrimitiveSizeInBits() const LLVM_READONLY
Return the basic size of this type if it is a primitive type.
bool isVoidTy() const
Return true if this is 'void'.
Definition: Type.h:140
static UndefValue * get(Type *T)
Static factory methods - Return an 'undef' object of the specified type.
Definition: Constants.cpp:1833
A Use represents the edge between a Value definition and its users.
Definition: Use.h:43
LLVM Value Representation.
Definition: Value.h:74
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:255
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:534
iterator_range< user_iterator > users()
Definition: Value.h:421
const Value * stripPointerCasts() const
Strip off pointer casts, all-zero GEPs and address space casts.
Definition: Value.cpp:694
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:1075
iterator_range< use_iterator > uses()
Definition: Value.h:376
StringRef getName() const
Return a constant reference to the value's name.
Definition: Value.cpp:309
void takeName(Value *V)
Transfer the name from V to this value.
Definition: Value.cpp:383
Value handle that is nullable, but tries to track the Value.
Definition: ValueHandle.h:204
size_type count(const_arg_type_t< ValueT > V) const
Return 1 if the specified key is in the set, 0 otherwise.
Definition: DenseSet.h:97
An efficient, type-erasing, non-owning reference to a callable.
const ParentTy * getParent() const
Definition: ilist_node.h:32
self_iterator getIterator()
Definition: ilist_node.h:132
iterator insert(iterator where, pointer New)
Definition: ilist.h:165
A raw_ostream that writes to a file descriptor.
Definition: raw_ostream.h:460
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
A raw_ostream that writes to an std::string.
Definition: raw_ostream.h:661
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
bool isAssumedReadNone(Attributor &A, const IRPosition &IRP, const AbstractAttribute &QueryingAA, bool &IsKnown)
Return true if IRP is readnone.
Definition: Attributor.cpp:654
bool isAssumedReadOnly(Attributor &A, const IRPosition &IRP, const AbstractAttribute &QueryingAA, bool &IsKnown)
Return true if IRP is readonly.
Definition: Attributor.cpp:649
std::optional< Value * > combineOptionalValuesInAAValueLatice(const std::optional< Value * > &A, const std::optional< Value * > &B, Type *Ty)
Return the combination of A and B such that the result is a possible value of both.
Definition: Attributor.cpp:340
bool isValidAtPosition(const ValueAndContext &VAC, InformationCache &InfoCache)
Return true if the value of VAC is a valid at the position of VAC, that is a constant,...
Definition: Attributor.cpp:291
bool isAssumedThreadLocalObject(Attributor &A, Value &Obj, const AbstractAttribute &QueryingAA)
Return true if Obj is assumed to be a thread local object.
Definition: Attributor.cpp:836
bool isDynamicallyUnique(Attributor &A, const AbstractAttribute &QueryingAA, const Value &V, bool ForAnalysisOnly=true)
Return true if V is dynamically unique, that is, there are no two "instances" of V at runtime with di...
Definition: Attributor.cpp:232
bool getPotentialCopiesOfStoredValue(Attributor &A, StoreInst &SI, SmallSetVector< Value *, 4 > &PotentialCopies, const AbstractAttribute &QueryingAA, bool &UsedAssumedInformation, bool OnlyExact=false)
Collect all potential values of the one stored by SI into PotentialCopies.
Definition: Attributor.cpp:600
bool isPotentiallyAffectedByBarrier(Attributor &A, const Instruction &I, const AbstractAttribute &QueryingAA)
Return true if I is potentially affected by a barrier.
Definition: Attributor.cpp:890
bool isGPU(const Module &M)
Return true iff M target a GPU (and we can use GPU AS reasoning).
Definition: Attributor.cpp:201
Constant * getInitialValueForObj(Attributor &A, const AbstractAttribute &QueryingAA, Value &Obj, Type &Ty, const TargetLibraryInfo *TLI, const DataLayout &DL, RangeTy *RangePtr=nullptr)
Return the initial value of Obj with type Ty if that is a constant.
Definition: Attributor.cpp:243
ValueScope
Flags to distinguish intra-procedural queries from potentially inter-procedural queries.
Definition: Attributor.h:180
@ Intraprocedural
Definition: Attributor.h:181
@ Interprocedural
Definition: Attributor.h:182
bool isValidInScope(const Value &V, const Function *Scope)
Return true if V is a valid value in Scope, that is a constant or an instruction/argument of Scope.
Definition: Attributor.cpp:281
bool isPotentiallyReachable(Attributor &A, const Instruction &FromI, const Instruction &ToI, const AbstractAttribute &QueryingAA, const AA::InstExclusionSetTy *ExclusionSet=nullptr, std::function< bool(const Function &F)> GoBackwardsCB=nullptr)
Return true if ToI is potentially reachable from FromI without running into any instruction in Exclus...
Definition: Attributor.cpp:817
bool isNoSyncInst(Attributor &A, const Instruction &I, const AbstractAttribute &QueryingAA)
Return true if I is a nosync instruction.
Definition: Attributor.cpp:206
bool getPotentiallyLoadedValues(Attributor &A, LoadInst &LI, SmallSetVector< Value *, 4 > &PotentialValues, SmallSetVector< Instruction *, 4 > &PotentialValueOrigins, const AbstractAttribute &QueryingAA, bool &UsedAssumedInformation, bool OnlyExact=false)
Collect all potential values LI could read into PotentialValues.
Definition: Attributor.cpp:590