1 //===- AssumeBundleBuilder.cpp - tools to preserve informations -*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "llvm/Transforms/Utils/AssumeBundleBuilder.h" 10 #include "llvm/ADT/DepthFirstIterator.h" 11 #include "llvm/ADT/MapVector.h" 12 #include "llvm/ADT/Statistic.h" 13 #include "llvm/Analysis/AssumeBundleQueries.h" 14 #include "llvm/Analysis/AssumptionCache.h" 15 #include "llvm/Analysis/ValueTracking.h" 16 #include "llvm/IR/Dominators.h" 17 #include "llvm/IR/Function.h" 18 #include "llvm/IR/InstIterator.h" 19 #include "llvm/IR/IntrinsicInst.h" 20 #include "llvm/IR/Module.h" 21 #include "llvm/IR/Operator.h" 22 #include "llvm/InitializePasses.h" 23 #include "llvm/Support/CommandLine.h" 24 #include "llvm/Support/DebugCounter.h" 25 #include "llvm/Transforms/Utils/Local.h" 26 27 using namespace llvm; 28 29 namespace llvm { 30 cl::opt<bool> ShouldPreserveAllAttributes( 31 "assume-preserve-all", cl::init(false), cl::Hidden, 32 cl::desc("enable preservation of all attrbitues. even those that are " 33 "unlikely to be usefull")); 34 35 cl::opt<bool> EnableKnowledgeRetention( 36 "enable-knowledge-retention", cl::init(false), cl::Hidden, 37 cl::desc( 38 "enable preservation of attributes throughout code transformation")); 39 } // namespace llvm 40 41 #define DEBUG_TYPE "assume-builder" 42 43 STATISTIC(NumAssumeBuilt, "Number of assume built by the assume builder"); 44 STATISTIC(NumBundlesInAssumes, "Total number of Bundles in the assume built"); 45 STATISTIC(NumAssumesMerged, 46 "Number of assume merged by the assume simplify pass"); 47 STATISTIC(NumAssumesRemoved, 48 "Number of assume removed by the assume simplify pass"); 49 50 DEBUG_COUNTER(BuildAssumeCounter, "assume-builder-counter", 51 "Controls which assumes gets created"); 52 53 namespace { 54 55 bool isUsefullToPreserve(Attribute::AttrKind Kind) { 56 switch (Kind) { 57 case Attribute::NonNull: 58 case Attribute::NoUndef: 59 case Attribute::Alignment: 60 case Attribute::Dereferenceable: 61 case Attribute::DereferenceableOrNull: 62 case Attribute::Cold: 63 return true; 64 default: 65 return false; 66 } 67 } 68 69 /// This function will try to transform the given knowledge into a more 70 /// canonical one. the canonical knowledge maybe the given one. 71 RetainedKnowledge canonicalizedKnowledge(RetainedKnowledge RK, 72 const DataLayout &DL) { 73 switch (RK.AttrKind) { 74 default: 75 return RK; 76 case Attribute::NonNull: 77 RK.WasOn = getUnderlyingObject(RK.WasOn); 78 return RK; 79 case Attribute::Alignment: { 80 Value *V = RK.WasOn->stripInBoundsOffsets([&](const Value *Strip) { 81 if (auto *GEP = dyn_cast<GEPOperator>(Strip)) 82 RK.ArgValue = 83 MinAlign(RK.ArgValue, GEP->getMaxPreservedAlignment(DL).value()); 84 }); 85 RK.WasOn = V; 86 return RK; 87 } 88 case Attribute::Dereferenceable: 89 case Attribute::DereferenceableOrNull: { 90 int64_t Offset = 0; 91 Value *V = GetPointerBaseWithConstantOffset(RK.WasOn, Offset, DL, 92 /*AllowNonInBounds*/ false); 93 if (Offset < 0) 94 return RK; 95 RK.ArgValue = RK.ArgValue + Offset; 96 RK.WasOn = V; 97 } 98 } 99 return RK; 100 } 101 102 /// This class contain all knowledge that have been gather while building an 103 /// llvm.assume and the function to manipulate it. 104 struct AssumeBuilderState { 105 Module *M; 106 107 using MapKey = std::pair<Value *, Attribute::AttrKind>; 108 SmallMapVector<MapKey, uint64_t, 8> AssumedKnowledgeMap; 109 Instruction *InstBeingModified = nullptr; 110 AssumptionCache* AC = nullptr; 111 DominatorTree* DT = nullptr; 112 113 AssumeBuilderState(Module *M, Instruction *I = nullptr, 114 AssumptionCache *AC = nullptr, DominatorTree *DT = nullptr) 115 : M(M), InstBeingModified(I), AC(AC), DT(DT) {} 116 117 bool tryToPreserveWithoutAddingAssume(RetainedKnowledge RK) { 118 if (!InstBeingModified || !RK.WasOn) 119 return false; 120 bool HasBeenPreserved = false; 121 Use* ToUpdate = nullptr; 122 getKnowledgeForValue( 123 RK.WasOn, {RK.AttrKind}, AC, 124 [&](RetainedKnowledge RKOther, Instruction *Assume, 125 const CallInst::BundleOpInfo *Bundle) { 126 if (!isValidAssumeForContext(Assume, InstBeingModified, DT)) 127 return false; 128 if (RKOther.ArgValue >= RK.ArgValue) { 129 HasBeenPreserved = true; 130 return true; 131 } else if (isValidAssumeForContext(InstBeingModified, Assume, DT)) { 132 HasBeenPreserved = true; 133 IntrinsicInst *Intr = cast<IntrinsicInst>(Assume); 134 ToUpdate = &Intr->op_begin()[Bundle->Begin + ABA_Argument]; 135 return true; 136 } 137 return false; 138 }); 139 if (ToUpdate) 140 ToUpdate->set( 141 ConstantInt::get(Type::getInt64Ty(M->getContext()), RK.ArgValue)); 142 return HasBeenPreserved; 143 } 144 145 bool isKnowledgeWorthPreserving(RetainedKnowledge RK) { 146 if (!RK) 147 return false; 148 if (!RK.WasOn) 149 return true; 150 if (RK.WasOn->getType()->isPointerTy()) { 151 Value *UnderlyingPtr = getUnderlyingObject(RK.WasOn); 152 if (isa<AllocaInst>(UnderlyingPtr) || isa<GlobalValue>(UnderlyingPtr)) 153 return false; 154 } 155 if (auto *Arg = dyn_cast<Argument>(RK.WasOn)) { 156 if (Arg->hasAttribute(RK.AttrKind) && 157 (!Attribute::isIntAttrKind(RK.AttrKind) || 158 Arg->getAttribute(RK.AttrKind).getValueAsInt() >= RK.ArgValue)) 159 return false; 160 return true; 161 } 162 if (auto *Inst = dyn_cast<Instruction>(RK.WasOn)) 163 if (wouldInstructionBeTriviallyDead(Inst)) { 164 if (RK.WasOn->use_empty()) 165 return false; 166 Use *SingleUse = RK.WasOn->getSingleUndroppableUse(); 167 if (SingleUse && SingleUse->getUser() == InstBeingModified) 168 return false; 169 } 170 return true; 171 } 172 173 void addKnowledge(RetainedKnowledge RK) { 174 RK = canonicalizedKnowledge(RK, M->getDataLayout()); 175 176 if (!isKnowledgeWorthPreserving(RK)) 177 return; 178 179 if (tryToPreserveWithoutAddingAssume(RK)) 180 return; 181 MapKey Key{RK.WasOn, RK.AttrKind}; 182 auto Lookup = AssumedKnowledgeMap.find(Key); 183 if (Lookup == AssumedKnowledgeMap.end()) { 184 AssumedKnowledgeMap[Key] = RK.ArgValue; 185 return; 186 } 187 assert(((Lookup->second == 0 && RK.ArgValue == 0) || 188 (Lookup->second != 0 && RK.ArgValue != 0)) && 189 "inconsistent argument value"); 190 191 /// This is only desirable because for all attributes taking an argument 192 /// higher is better. 193 Lookup->second = std::max(Lookup->second, RK.ArgValue); 194 } 195 196 void addAttribute(Attribute Attr, Value *WasOn) { 197 if (Attr.isTypeAttribute() || Attr.isStringAttribute() || 198 (!ShouldPreserveAllAttributes && 199 !isUsefullToPreserve(Attr.getKindAsEnum()))) 200 return; 201 uint64_t AttrArg = 0; 202 if (Attr.isIntAttribute()) 203 AttrArg = Attr.getValueAsInt(); 204 addKnowledge({Attr.getKindAsEnum(), AttrArg, WasOn}); 205 } 206 207 void addCall(const CallBase *Call) { 208 auto addAttrList = [&](AttributeList AttrList, unsigned NumArgs) { 209 for (unsigned Idx = 0; Idx < NumArgs; Idx++) 210 for (Attribute Attr : AttrList.getParamAttrs(Idx)) { 211 bool IsPoisonAttr = Attr.hasAttribute(Attribute::NonNull) || 212 Attr.hasAttribute(Attribute::Alignment); 213 if (!IsPoisonAttr || Call->isPassingUndefUB(Idx)) 214 addAttribute(Attr, Call->getArgOperand(Idx)); 215 } 216 for (Attribute Attr : AttrList.getFnAttrs()) 217 addAttribute(Attr, nullptr); 218 }; 219 addAttrList(Call->getAttributes(), Call->arg_size()); 220 if (Function *Fn = Call->getCalledFunction()) 221 addAttrList(Fn->getAttributes(), Fn->arg_size()); 222 } 223 224 AssumeInst *build() { 225 if (AssumedKnowledgeMap.empty()) 226 return nullptr; 227 if (!DebugCounter::shouldExecute(BuildAssumeCounter)) 228 return nullptr; 229 Function *FnAssume = Intrinsic::getDeclaration(M, Intrinsic::assume); 230 LLVMContext &C = M->getContext(); 231 SmallVector<OperandBundleDef, 8> OpBundle; 232 for (auto &MapElem : AssumedKnowledgeMap) { 233 SmallVector<Value *, 2> Args; 234 if (MapElem.first.first) 235 Args.push_back(MapElem.first.first); 236 237 /// This is only valid because for all attribute that currently exist a 238 /// value of 0 is useless. and should not be preserved. 239 if (MapElem.second) 240 Args.push_back(ConstantInt::get(Type::getInt64Ty(M->getContext()), 241 MapElem.second)); 242 OpBundle.push_back(OperandBundleDefT<Value *>( 243 std::string(Attribute::getNameFromAttrKind(MapElem.first.second)), 244 Args)); 245 NumBundlesInAssumes++; 246 } 247 NumAssumeBuilt++; 248 return cast<AssumeInst>(CallInst::Create( 249 FnAssume, ArrayRef<Value *>({ConstantInt::getTrue(C)}), OpBundle)); 250 } 251 252 void addAccessedPtr(Instruction *MemInst, Value *Pointer, Type *AccType, 253 MaybeAlign MA) { 254 unsigned DerefSize = MemInst->getModule() 255 ->getDataLayout() 256 .getTypeStoreSize(AccType) 257 .getKnownMinValue(); 258 if (DerefSize != 0) { 259 addKnowledge({Attribute::Dereferenceable, DerefSize, Pointer}); 260 if (!NullPointerIsDefined(MemInst->getFunction(), 261 Pointer->getType()->getPointerAddressSpace())) 262 addKnowledge({Attribute::NonNull, 0u, Pointer}); 263 } 264 if (MA.valueOrOne() > 1) 265 addKnowledge({Attribute::Alignment, MA.valueOrOne().value(), Pointer}); 266 } 267 268 void addInstruction(Instruction *I) { 269 if (auto *Call = dyn_cast<CallBase>(I)) 270 return addCall(Call); 271 if (auto *Load = dyn_cast<LoadInst>(I)) 272 return addAccessedPtr(I, Load->getPointerOperand(), Load->getType(), 273 Load->getAlign()); 274 if (auto *Store = dyn_cast<StoreInst>(I)) 275 return addAccessedPtr(I, Store->getPointerOperand(), 276 Store->getValueOperand()->getType(), 277 Store->getAlign()); 278 // TODO: Add support for the other Instructions. 279 // TODO: Maybe we should look around and merge with other llvm.assume. 280 } 281 }; 282 283 } // namespace 284 285 AssumeInst *llvm::buildAssumeFromInst(Instruction *I) { 286 if (!EnableKnowledgeRetention) 287 return nullptr; 288 AssumeBuilderState Builder(I->getModule()); 289 Builder.addInstruction(I); 290 return Builder.build(); 291 } 292 293 void llvm::salvageKnowledge(Instruction *I, AssumptionCache *AC, 294 DominatorTree *DT) { 295 if (!EnableKnowledgeRetention || I->isTerminator()) 296 return; 297 AssumeBuilderState Builder(I->getModule(), I, AC, DT); 298 Builder.addInstruction(I); 299 if (auto *Intr = Builder.build()) { 300 Intr->insertBefore(I); 301 if (AC) 302 AC->registerAssumption(Intr); 303 } 304 } 305 306 AssumeInst * 307 llvm::buildAssumeFromKnowledge(ArrayRef<RetainedKnowledge> Knowledge, 308 Instruction *CtxI, AssumptionCache *AC, 309 DominatorTree *DT) { 310 AssumeBuilderState Builder(CtxI->getModule(), CtxI, AC, DT); 311 for (const RetainedKnowledge &RK : Knowledge) 312 Builder.addKnowledge(RK); 313 return Builder.build(); 314 } 315 316 RetainedKnowledge llvm::simplifyRetainedKnowledge(AssumeInst *Assume, 317 RetainedKnowledge RK, 318 AssumptionCache *AC, 319 DominatorTree *DT) { 320 AssumeBuilderState Builder(Assume->getModule(), Assume, AC, DT); 321 RK = canonicalizedKnowledge(RK, Assume->getModule()->getDataLayout()); 322 323 if (!Builder.isKnowledgeWorthPreserving(RK)) 324 return RetainedKnowledge::none(); 325 326 if (Builder.tryToPreserveWithoutAddingAssume(RK)) 327 return RetainedKnowledge::none(); 328 return RK; 329 } 330 331 namespace { 332 333 struct AssumeSimplify { 334 Function &F; 335 AssumptionCache &AC; 336 DominatorTree *DT; 337 LLVMContext &C; 338 SmallDenseSet<IntrinsicInst *> CleanupToDo; 339 StringMapEntry<uint32_t> *IgnoreTag; 340 SmallDenseMap<BasicBlock *, SmallVector<IntrinsicInst *, 4>, 8> BBToAssume; 341 bool MadeChange = false; 342 343 AssumeSimplify(Function &F, AssumptionCache &AC, DominatorTree *DT, 344 LLVMContext &C) 345 : F(F), AC(AC), DT(DT), C(C), 346 IgnoreTag(C.getOrInsertBundleTag(IgnoreBundleTag)) {} 347 348 void buildMapping(bool FilterBooleanArgument) { 349 BBToAssume.clear(); 350 for (Value *V : AC.assumptions()) { 351 if (!V) 352 continue; 353 IntrinsicInst *Assume = cast<IntrinsicInst>(V); 354 if (FilterBooleanArgument) { 355 auto *Arg = dyn_cast<ConstantInt>(Assume->getOperand(0)); 356 if (!Arg || Arg->isZero()) 357 continue; 358 } 359 BBToAssume[Assume->getParent()].push_back(Assume); 360 } 361 362 for (auto &Elem : BBToAssume) { 363 llvm::sort(Elem.second, 364 [](const IntrinsicInst *LHS, const IntrinsicInst *RHS) { 365 return LHS->comesBefore(RHS); 366 }); 367 } 368 } 369 370 /// Remove all asumes in CleanupToDo if there boolean argument is true and 371 /// ForceCleanup is set or the assume doesn't hold valuable knowledge. 372 void RunCleanup(bool ForceCleanup) { 373 for (IntrinsicInst *Assume : CleanupToDo) { 374 auto *Arg = dyn_cast<ConstantInt>(Assume->getOperand(0)); 375 if (!Arg || Arg->isZero() || 376 (!ForceCleanup && 377 !isAssumeWithEmptyBundle(cast<AssumeInst>(*Assume)))) 378 continue; 379 MadeChange = true; 380 if (ForceCleanup) 381 NumAssumesMerged++; 382 else 383 NumAssumesRemoved++; 384 Assume->eraseFromParent(); 385 } 386 CleanupToDo.clear(); 387 } 388 389 /// Remove knowledge stored in assume when it is already know by an attribute 390 /// or an other assume. This can when valid update an existing knowledge in an 391 /// attribute or an other assume. 392 void dropRedundantKnowledge() { 393 struct MapValue { 394 IntrinsicInst *Assume; 395 uint64_t ArgValue; 396 CallInst::BundleOpInfo *BOI; 397 }; 398 buildMapping(false); 399 SmallDenseMap<std::pair<Value *, Attribute::AttrKind>, 400 SmallVector<MapValue, 2>, 16> 401 Knowledge; 402 for (BasicBlock *BB : depth_first(&F)) 403 for (Value *V : BBToAssume[BB]) { 404 if (!V) 405 continue; 406 IntrinsicInst *Assume = cast<IntrinsicInst>(V); 407 for (CallInst::BundleOpInfo &BOI : Assume->bundle_op_infos()) { 408 auto RemoveFromAssume = [&]() { 409 CleanupToDo.insert(Assume); 410 if (BOI.Begin != BOI.End) { 411 Use *U = &Assume->op_begin()[BOI.Begin + ABA_WasOn]; 412 U->set(UndefValue::get(U->get()->getType())); 413 } 414 BOI.Tag = IgnoreTag; 415 }; 416 if (BOI.Tag == IgnoreTag) { 417 CleanupToDo.insert(Assume); 418 continue; 419 } 420 RetainedKnowledge RK = 421 getKnowledgeFromBundle(cast<AssumeInst>(*Assume), BOI); 422 if (auto *Arg = dyn_cast_or_null<Argument>(RK.WasOn)) { 423 bool HasSameKindAttr = Arg->hasAttribute(RK.AttrKind); 424 if (HasSameKindAttr) 425 if (!Attribute::isIntAttrKind(RK.AttrKind) || 426 Arg->getAttribute(RK.AttrKind).getValueAsInt() >= 427 RK.ArgValue) { 428 RemoveFromAssume(); 429 continue; 430 } 431 if (isValidAssumeForContext( 432 Assume, &*F.getEntryBlock().getFirstInsertionPt()) || 433 Assume == &*F.getEntryBlock().getFirstInsertionPt()) { 434 if (HasSameKindAttr) 435 Arg->removeAttr(RK.AttrKind); 436 Arg->addAttr(Attribute::get(C, RK.AttrKind, RK.ArgValue)); 437 MadeChange = true; 438 RemoveFromAssume(); 439 continue; 440 } 441 } 442 auto &Lookup = Knowledge[{RK.WasOn, RK.AttrKind}]; 443 for (MapValue &Elem : Lookup) { 444 if (!isValidAssumeForContext(Elem.Assume, Assume, DT)) 445 continue; 446 if (Elem.ArgValue >= RK.ArgValue) { 447 RemoveFromAssume(); 448 continue; 449 } else if (isValidAssumeForContext(Assume, Elem.Assume, DT)) { 450 Elem.Assume->op_begin()[Elem.BOI->Begin + ABA_Argument].set( 451 ConstantInt::get(Type::getInt64Ty(C), RK.ArgValue)); 452 MadeChange = true; 453 RemoveFromAssume(); 454 continue; 455 } 456 } 457 Lookup.push_back({Assume, RK.ArgValue, &BOI}); 458 } 459 } 460 } 461 462 using MergeIterator = SmallVectorImpl<IntrinsicInst *>::iterator; 463 464 /// Merge all Assumes from Begin to End in and insert the resulting assume as 465 /// high as possible in the basicblock. 466 void mergeRange(BasicBlock *BB, MergeIterator Begin, MergeIterator End) { 467 if (Begin == End || std::next(Begin) == End) 468 return; 469 /// Provide no additional information so that AssumeBuilderState doesn't 470 /// try to do any punning since it already has been done better. 471 AssumeBuilderState Builder(F.getParent()); 472 473 /// For now it is initialized to the best value it could have 474 Instruction *InsertPt = BB->getFirstNonPHI(); 475 if (isa<LandingPadInst>(InsertPt)) 476 InsertPt = InsertPt->getNextNode(); 477 for (IntrinsicInst *I : make_range(Begin, End)) { 478 CleanupToDo.insert(I); 479 for (CallInst::BundleOpInfo &BOI : I->bundle_op_infos()) { 480 RetainedKnowledge RK = 481 getKnowledgeFromBundle(cast<AssumeInst>(*I), BOI); 482 if (!RK) 483 continue; 484 Builder.addKnowledge(RK); 485 if (auto *I = dyn_cast_or_null<Instruction>(RK.WasOn)) 486 if (I->getParent() == InsertPt->getParent() && 487 (InsertPt->comesBefore(I) || InsertPt == I)) 488 InsertPt = I->getNextNode(); 489 } 490 } 491 492 /// Adjust InsertPt if it is before Begin, since mergeAssumes only 493 /// guarantees we can place the resulting assume between Begin and End. 494 if (InsertPt->comesBefore(*Begin)) 495 for (auto It = (*Begin)->getIterator(), E = InsertPt->getIterator(); 496 It != E; --It) 497 if (!isGuaranteedToTransferExecutionToSuccessor(&*It)) { 498 InsertPt = It->getNextNode(); 499 break; 500 } 501 auto *MergedAssume = Builder.build(); 502 if (!MergedAssume) 503 return; 504 MadeChange = true; 505 MergedAssume->insertBefore(InsertPt); 506 AC.registerAssumption(MergedAssume); 507 } 508 509 /// Merge assume when they are in the same BasicBlock and for all instruction 510 /// between them isGuaranteedToTransferExecutionToSuccessor returns true. 511 void mergeAssumes() { 512 buildMapping(true); 513 514 SmallVector<MergeIterator, 4> SplitPoints; 515 for (auto &Elem : BBToAssume) { 516 SmallVectorImpl<IntrinsicInst *> &AssumesInBB = Elem.second; 517 if (AssumesInBB.size() < 2) 518 continue; 519 /// AssumesInBB is already sorted by order in the block. 520 521 BasicBlock::iterator It = AssumesInBB.front()->getIterator(); 522 BasicBlock::iterator E = AssumesInBB.back()->getIterator(); 523 SplitPoints.push_back(AssumesInBB.begin()); 524 MergeIterator LastSplit = AssumesInBB.begin(); 525 for (; It != E; ++It) 526 if (!isGuaranteedToTransferExecutionToSuccessor(&*It)) { 527 for (; (*LastSplit)->comesBefore(&*It); ++LastSplit) 528 ; 529 if (SplitPoints.back() != LastSplit) 530 SplitPoints.push_back(LastSplit); 531 } 532 SplitPoints.push_back(AssumesInBB.end()); 533 for (auto SplitIt = SplitPoints.begin(); 534 SplitIt != std::prev(SplitPoints.end()); SplitIt++) { 535 mergeRange(Elem.first, *SplitIt, *(SplitIt + 1)); 536 } 537 SplitPoints.clear(); 538 } 539 } 540 }; 541 542 bool simplifyAssumes(Function &F, AssumptionCache *AC, DominatorTree *DT) { 543 AssumeSimplify AS(F, *AC, DT, F.getContext()); 544 545 /// Remove knowledge that is already known by a dominating other assume or an 546 /// attribute. 547 AS.dropRedundantKnowledge(); 548 549 /// Remove assume that are empty. 550 AS.RunCleanup(false); 551 552 /// Merge assume in the same basicblock when possible. 553 AS.mergeAssumes(); 554 555 /// Remove assume that were merged. 556 AS.RunCleanup(true); 557 return AS.MadeChange; 558 } 559 560 } // namespace 561 562 PreservedAnalyses AssumeSimplifyPass::run(Function &F, 563 FunctionAnalysisManager &AM) { 564 if (!EnableKnowledgeRetention) 565 return PreservedAnalyses::all(); 566 simplifyAssumes(F, &AM.getResult<AssumptionAnalysis>(F), 567 AM.getCachedResult<DominatorTreeAnalysis>(F)); 568 return PreservedAnalyses::all(); 569 } 570 571 namespace { 572 class AssumeSimplifyPassLegacyPass : public FunctionPass { 573 public: 574 static char ID; 575 576 AssumeSimplifyPassLegacyPass() : FunctionPass(ID) { 577 initializeAssumeSimplifyPassLegacyPassPass( 578 *PassRegistry::getPassRegistry()); 579 } 580 bool runOnFunction(Function &F) override { 581 if (skipFunction(F) || !EnableKnowledgeRetention) 582 return false; 583 AssumptionCache &AC = 584 getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F); 585 DominatorTreeWrapperPass *DTWP = 586 getAnalysisIfAvailable<DominatorTreeWrapperPass>(); 587 return simplifyAssumes(F, &AC, DTWP ? &DTWP->getDomTree() : nullptr); 588 } 589 590 void getAnalysisUsage(AnalysisUsage &AU) const override { 591 AU.addRequired<AssumptionCacheTracker>(); 592 593 AU.setPreservesAll(); 594 } 595 }; 596 } // namespace 597 598 char AssumeSimplifyPassLegacyPass::ID = 0; 599 600 INITIALIZE_PASS_BEGIN(AssumeSimplifyPassLegacyPass, "assume-simplify", 601 "Assume Simplify", false, false) 602 INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker) 603 INITIALIZE_PASS_END(AssumeSimplifyPassLegacyPass, "assume-simplify", 604 "Assume Simplify", false, false) 605 606 FunctionPass *llvm::createAssumeSimplifyPass() { 607 return new AssumeSimplifyPassLegacyPass(); 608 } 609 610 PreservedAnalyses AssumeBuilderPass::run(Function &F, 611 FunctionAnalysisManager &AM) { 612 AssumptionCache *AC = &AM.getResult<AssumptionAnalysis>(F); 613 DominatorTree* DT = AM.getCachedResult<DominatorTreeAnalysis>(F); 614 for (Instruction &I : instructions(F)) 615 salvageKnowledge(&I, AC, DT); 616 return PreservedAnalyses::all(); 617 } 618 619 namespace { 620 class AssumeBuilderPassLegacyPass : public FunctionPass { 621 public: 622 static char ID; 623 624 AssumeBuilderPassLegacyPass() : FunctionPass(ID) { 625 initializeAssumeBuilderPassLegacyPassPass(*PassRegistry::getPassRegistry()); 626 } 627 bool runOnFunction(Function &F) override { 628 AssumptionCache &AC = 629 getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F); 630 DominatorTreeWrapperPass *DTWP = 631 getAnalysisIfAvailable<DominatorTreeWrapperPass>(); 632 for (Instruction &I : instructions(F)) 633 salvageKnowledge(&I, &AC, DTWP ? &DTWP->getDomTree() : nullptr); 634 return true; 635 } 636 637 void getAnalysisUsage(AnalysisUsage &AU) const override { 638 AU.addRequired<AssumptionCacheTracker>(); 639 640 AU.setPreservesAll(); 641 } 642 }; 643 } // namespace 644 645 char AssumeBuilderPassLegacyPass::ID = 0; 646 647 INITIALIZE_PASS_BEGIN(AssumeBuilderPassLegacyPass, "assume-builder", 648 "Assume Builder", false, false) 649 INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker) 650 INITIALIZE_PASS_END(AssumeBuilderPassLegacyPass, "assume-builder", 651 "Assume Builder", false, false) 652