1 //===- AliasSetTracker.cpp - Alias Sets Tracker implementation-------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements the AliasSetTracker and AliasSet classes. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Analysis/AliasSetTracker.h" 15 #include "llvm/Analysis/AliasAnalysis.h" 16 #include "llvm/IR/DataLayout.h" 17 #include "llvm/IR/InstIterator.h" 18 #include "llvm/IR/Instructions.h" 19 #include "llvm/IR/IntrinsicInst.h" 20 #include "llvm/IR/LLVMContext.h" 21 #include "llvm/IR/Type.h" 22 #include "llvm/Pass.h" 23 #include "llvm/Support/Debug.h" 24 #include "llvm/Support/ErrorHandling.h" 25 #include "llvm/Support/raw_ostream.h" 26 using namespace llvm; 27 28 /// mergeSetIn - Merge the specified alias set into this alias set. 29 /// 30 void AliasSet::mergeSetIn(AliasSet &AS, AliasSetTracker &AST) { 31 assert(!AS.Forward && "Alias set is already forwarding!"); 32 assert(!Forward && "This set is a forwarding set!!"); 33 34 // Update the alias and access types of this set... 35 AccessTy |= AS.AccessTy; 36 AliasTy |= AS.AliasTy; 37 Volatile |= AS.Volatile; 38 39 if (AliasTy == MustAlias) { 40 // Check that these two merged sets really are must aliases. Since both 41 // used to be must-alias sets, we can just check any pointer from each set 42 // for aliasing. 43 AliasAnalysis &AA = AST.getAliasAnalysis(); 44 PointerRec *L = getSomePointer(); 45 PointerRec *R = AS.getSomePointer(); 46 47 // If the pointers are not a must-alias pair, this set becomes a may alias. 48 if (AA.alias(AliasAnalysis::Location(L->getValue(), 49 L->getSize(), 50 L->getAAInfo()), 51 AliasAnalysis::Location(R->getValue(), 52 R->getSize(), 53 R->getAAInfo())) 54 != AliasAnalysis::MustAlias) 55 AliasTy = MayAlias; 56 } 57 58 bool ASHadUnknownInsts = !AS.UnknownInsts.empty(); 59 if (UnknownInsts.empty()) { // Merge call sites... 60 if (ASHadUnknownInsts) { 61 std::swap(UnknownInsts, AS.UnknownInsts); 62 addRef(); 63 } 64 } else if (ASHadUnknownInsts) { 65 UnknownInsts.insert(UnknownInsts.end(), AS.UnknownInsts.begin(), AS.UnknownInsts.end()); 66 AS.UnknownInsts.clear(); 67 } 68 69 AS.Forward = this; // Forward across AS now... 70 addRef(); // AS is now pointing to us... 71 72 // Merge the list of constituent pointers... 73 if (AS.PtrList) { 74 *PtrListEnd = AS.PtrList; 75 AS.PtrList->setPrevInList(PtrListEnd); 76 PtrListEnd = AS.PtrListEnd; 77 78 AS.PtrList = nullptr; 79 AS.PtrListEnd = &AS.PtrList; 80 assert(*AS.PtrListEnd == nullptr && "End of list is not null?"); 81 } 82 if (ASHadUnknownInsts) 83 AS.dropRef(AST); 84 } 85 86 void AliasSetTracker::removeAliasSet(AliasSet *AS) { 87 if (AliasSet *Fwd = AS->Forward) { 88 Fwd->dropRef(*this); 89 AS->Forward = nullptr; 90 } 91 AliasSets.erase(AS); 92 } 93 94 void AliasSet::removeFromTracker(AliasSetTracker &AST) { 95 assert(RefCount == 0 && "Cannot remove non-dead alias set from tracker!"); 96 AST.removeAliasSet(this); 97 } 98 99 void AliasSet::addPointer(AliasSetTracker &AST, PointerRec &Entry, 100 uint64_t Size, const AAMDNodes &AAInfo, 101 bool KnownMustAlias) { 102 assert(!Entry.hasAliasSet() && "Entry already in set!"); 103 104 // Check to see if we have to downgrade to _may_ alias. 105 if (isMustAlias() && !KnownMustAlias) 106 if (PointerRec *P = getSomePointer()) { 107 AliasAnalysis &AA = AST.getAliasAnalysis(); 108 AliasAnalysis::AliasResult Result = 109 AA.alias(AliasAnalysis::Location(P->getValue(), P->getSize(), 110 P->getAAInfo()), 111 AliasAnalysis::Location(Entry.getValue(), Size, AAInfo)); 112 if (Result != AliasAnalysis::MustAlias) 113 AliasTy = MayAlias; 114 else // First entry of must alias must have maximum size! 115 P->updateSizeAndAAInfo(Size, AAInfo); 116 assert(Result != AliasAnalysis::NoAlias && "Cannot be part of must set!"); 117 } 118 119 Entry.setAliasSet(this); 120 Entry.updateSizeAndAAInfo(Size, AAInfo); 121 122 // Add it to the end of the list... 123 assert(*PtrListEnd == nullptr && "End of list is not null?"); 124 *PtrListEnd = &Entry; 125 PtrListEnd = Entry.setPrevInList(PtrListEnd); 126 assert(*PtrListEnd == nullptr && "End of list is not null?"); 127 addRef(); // Entry points to alias set. 128 } 129 130 void AliasSet::addUnknownInst(Instruction *I, AliasAnalysis &AA) { 131 if (UnknownInsts.empty()) 132 addRef(); 133 UnknownInsts.push_back(I); 134 135 if (!I->mayWriteToMemory()) { 136 AliasTy = MayAlias; 137 AccessTy |= Refs; 138 return; 139 } 140 141 // FIXME: This should use mod/ref information to make this not suck so bad 142 AliasTy = MayAlias; 143 AccessTy = ModRef; 144 } 145 146 /// aliasesPointer - Return true if the specified pointer "may" (or must) 147 /// alias one of the members in the set. 148 /// 149 bool AliasSet::aliasesPointer(const Value *Ptr, uint64_t Size, 150 const AAMDNodes &AAInfo, 151 AliasAnalysis &AA) const { 152 if (AliasTy == MustAlias) { 153 assert(UnknownInsts.empty() && "Illegal must alias set!"); 154 155 // If this is a set of MustAliases, only check to see if the pointer aliases 156 // SOME value in the set. 157 PointerRec *SomePtr = getSomePointer(); 158 assert(SomePtr && "Empty must-alias set??"); 159 return AA.alias(AliasAnalysis::Location(SomePtr->getValue(), 160 SomePtr->getSize(), 161 SomePtr->getAAInfo()), 162 AliasAnalysis::Location(Ptr, Size, AAInfo)); 163 } 164 165 // If this is a may-alias set, we have to check all of the pointers in the set 166 // to be sure it doesn't alias the set... 167 for (iterator I = begin(), E = end(); I != E; ++I) 168 if (AA.alias(AliasAnalysis::Location(Ptr, Size, AAInfo), 169 AliasAnalysis::Location(I.getPointer(), I.getSize(), 170 I.getAAInfo()))) 171 return true; 172 173 // Check the unknown instructions... 174 if (!UnknownInsts.empty()) { 175 for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) 176 if (AA.getModRefInfo(UnknownInsts[i], 177 AliasAnalysis::Location(Ptr, Size, AAInfo)) != 178 AliasAnalysis::NoModRef) 179 return true; 180 } 181 182 return false; 183 } 184 185 bool AliasSet::aliasesUnknownInst(Instruction *Inst, AliasAnalysis &AA) const { 186 if (!Inst->mayReadOrWriteMemory()) 187 return false; 188 189 for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) { 190 CallSite C1(getUnknownInst(i)), C2(Inst); 191 if (!C1 || !C2 || 192 AA.getModRefInfo(C1, C2) != AliasAnalysis::NoModRef || 193 AA.getModRefInfo(C2, C1) != AliasAnalysis::NoModRef) 194 return true; 195 } 196 197 for (iterator I = begin(), E = end(); I != E; ++I) 198 if (AA.getModRefInfo(Inst, AliasAnalysis::Location(I.getPointer(), 199 I.getSize(), 200 I.getAAInfo())) != 201 AliasAnalysis::NoModRef) 202 return true; 203 204 return false; 205 } 206 207 void AliasSetTracker::clear() { 208 // Delete all the PointerRec entries. 209 for (PointerMapType::iterator I = PointerMap.begin(), E = PointerMap.end(); 210 I != E; ++I) 211 I->second->eraseFromList(); 212 213 PointerMap.clear(); 214 215 // The alias sets should all be clear now. 216 AliasSets.clear(); 217 } 218 219 220 /// findAliasSetForPointer - Given a pointer, find the one alias set to put the 221 /// instruction referring to the pointer into. If there are multiple alias sets 222 /// that may alias the pointer, merge them together and return the unified set. 223 /// 224 AliasSet *AliasSetTracker::findAliasSetForPointer(const Value *Ptr, 225 uint64_t Size, 226 const AAMDNodes &AAInfo) { 227 AliasSet *FoundSet = nullptr; 228 for (iterator I = begin(), E = end(); I != E;) { 229 iterator Cur = I++; 230 if (Cur->Forward || !Cur->aliasesPointer(Ptr, Size, AAInfo, AA)) continue; 231 232 if (!FoundSet) { // If this is the first alias set ptr can go into. 233 FoundSet = Cur; // Remember it. 234 } else { // Otherwise, we must merge the sets. 235 FoundSet->mergeSetIn(*Cur, *this); // Merge in contents. 236 } 237 } 238 239 return FoundSet; 240 } 241 242 /// containsPointer - Return true if the specified location is represented by 243 /// this alias set, false otherwise. This does not modify the AST object or 244 /// alias sets. 245 bool AliasSetTracker::containsPointer(Value *Ptr, uint64_t Size, 246 const AAMDNodes &AAInfo) const { 247 for (const_iterator I = begin(), E = end(); I != E; ++I) 248 if (!I->Forward && I->aliasesPointer(Ptr, Size, AAInfo, AA)) 249 return true; 250 return false; 251 } 252 253 bool AliasSetTracker::containsUnknown(Instruction *Inst) const { 254 for (const_iterator I = begin(), E = end(); I != E; ++I) 255 if (!I->Forward && I->aliasesUnknownInst(Inst, AA)) 256 return true; 257 return false; 258 } 259 260 AliasSet *AliasSetTracker::findAliasSetForUnknownInst(Instruction *Inst) { 261 AliasSet *FoundSet = nullptr; 262 for (iterator I = begin(), E = end(); I != E;) { 263 iterator Cur = I++; 264 if (Cur->Forward || !Cur->aliasesUnknownInst(Inst, AA)) 265 continue; 266 if (!FoundSet) // If this is the first alias set ptr can go into. 267 FoundSet = Cur; // Remember it. 268 else if (!Cur->Forward) // Otherwise, we must merge the sets. 269 FoundSet->mergeSetIn(*Cur, *this); // Merge in contents. 270 } 271 return FoundSet; 272 } 273 274 275 276 277 /// getAliasSetForPointer - Return the alias set that the specified pointer 278 /// lives in. 279 AliasSet &AliasSetTracker::getAliasSetForPointer(Value *Pointer, uint64_t Size, 280 const AAMDNodes &AAInfo, 281 bool *New) { 282 AliasSet::PointerRec &Entry = getEntryFor(Pointer); 283 284 // Check to see if the pointer is already known. 285 if (Entry.hasAliasSet()) { 286 Entry.updateSizeAndAAInfo(Size, AAInfo); 287 // Return the set! 288 return *Entry.getAliasSet(*this)->getForwardedTarget(*this); 289 } 290 291 if (AliasSet *AS = findAliasSetForPointer(Pointer, Size, AAInfo)) { 292 // Add it to the alias set it aliases. 293 AS->addPointer(*this, Entry, Size, AAInfo); 294 return *AS; 295 } 296 297 if (New) *New = true; 298 // Otherwise create a new alias set to hold the loaded pointer. 299 AliasSets.push_back(new AliasSet()); 300 AliasSets.back().addPointer(*this, Entry, Size, AAInfo); 301 return AliasSets.back(); 302 } 303 304 bool AliasSetTracker::add(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo) { 305 bool NewPtr; 306 addPointer(Ptr, Size, AAInfo, AliasSet::NoModRef, NewPtr); 307 return NewPtr; 308 } 309 310 311 bool AliasSetTracker::add(LoadInst *LI) { 312 if (LI->getOrdering() > Monotonic) return addUnknown(LI); 313 314 AAMDNodes AAInfo; 315 LI->getAAMetadata(AAInfo); 316 317 AliasSet::AccessType ATy = AliasSet::Refs; 318 bool NewPtr; 319 AliasSet &AS = addPointer(LI->getOperand(0), 320 AA.getTypeStoreSize(LI->getType()), 321 AAInfo, ATy, NewPtr); 322 if (LI->isVolatile()) AS.setVolatile(); 323 return NewPtr; 324 } 325 326 bool AliasSetTracker::add(StoreInst *SI) { 327 if (SI->getOrdering() > Monotonic) return addUnknown(SI); 328 329 AAMDNodes AAInfo; 330 SI->getAAMetadata(AAInfo); 331 332 AliasSet::AccessType ATy = AliasSet::Mods; 333 bool NewPtr; 334 Value *Val = SI->getOperand(0); 335 AliasSet &AS = addPointer(SI->getOperand(1), 336 AA.getTypeStoreSize(Val->getType()), 337 AAInfo, ATy, NewPtr); 338 if (SI->isVolatile()) AS.setVolatile(); 339 return NewPtr; 340 } 341 342 bool AliasSetTracker::add(VAArgInst *VAAI) { 343 AAMDNodes AAInfo; 344 VAAI->getAAMetadata(AAInfo); 345 346 bool NewPtr; 347 addPointer(VAAI->getOperand(0), AliasAnalysis::UnknownSize, 348 AAInfo, AliasSet::ModRef, NewPtr); 349 return NewPtr; 350 } 351 352 353 bool AliasSetTracker::addUnknown(Instruction *Inst) { 354 if (isa<DbgInfoIntrinsic>(Inst)) 355 return true; // Ignore DbgInfo Intrinsics. 356 if (!Inst->mayReadOrWriteMemory()) 357 return true; // doesn't alias anything 358 359 AliasSet *AS = findAliasSetForUnknownInst(Inst); 360 if (AS) { 361 AS->addUnknownInst(Inst, AA); 362 return false; 363 } 364 AliasSets.push_back(new AliasSet()); 365 AS = &AliasSets.back(); 366 AS->addUnknownInst(Inst, AA); 367 return true; 368 } 369 370 bool AliasSetTracker::add(Instruction *I) { 371 // Dispatch to one of the other add methods. 372 if (LoadInst *LI = dyn_cast<LoadInst>(I)) 373 return add(LI); 374 if (StoreInst *SI = dyn_cast<StoreInst>(I)) 375 return add(SI); 376 if (VAArgInst *VAAI = dyn_cast<VAArgInst>(I)) 377 return add(VAAI); 378 return addUnknown(I); 379 } 380 381 void AliasSetTracker::add(BasicBlock &BB) { 382 for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) 383 add(I); 384 } 385 386 void AliasSetTracker::add(const AliasSetTracker &AST) { 387 assert(&AA == &AST.AA && 388 "Merging AliasSetTracker objects with different Alias Analyses!"); 389 390 // Loop over all of the alias sets in AST, adding the pointers contained 391 // therein into the current alias sets. This can cause alias sets to be 392 // merged together in the current AST. 393 for (const_iterator I = AST.begin(), E = AST.end(); I != E; ++I) { 394 if (I->Forward) continue; // Ignore forwarding alias sets 395 396 AliasSet &AS = const_cast<AliasSet&>(*I); 397 398 // If there are any call sites in the alias set, add them to this AST. 399 for (unsigned i = 0, e = AS.UnknownInsts.size(); i != e; ++i) 400 add(AS.UnknownInsts[i]); 401 402 // Loop over all of the pointers in this alias set. 403 bool X; 404 for (AliasSet::iterator ASI = AS.begin(), E = AS.end(); ASI != E; ++ASI) { 405 AliasSet &NewAS = addPointer(ASI.getPointer(), ASI.getSize(), 406 ASI.getAAInfo(), 407 (AliasSet::AccessType)AS.AccessTy, X); 408 if (AS.isVolatile()) NewAS.setVolatile(); 409 } 410 } 411 } 412 413 /// remove - Remove the specified (potentially non-empty) alias set from the 414 /// tracker. 415 void AliasSetTracker::remove(AliasSet &AS) { 416 // Drop all call sites. 417 if (!AS.UnknownInsts.empty()) 418 AS.dropRef(*this); 419 AS.UnknownInsts.clear(); 420 421 // Clear the alias set. 422 unsigned NumRefs = 0; 423 while (!AS.empty()) { 424 AliasSet::PointerRec *P = AS.PtrList; 425 426 Value *ValToRemove = P->getValue(); 427 428 // Unlink and delete entry from the list of values. 429 P->eraseFromList(); 430 431 // Remember how many references need to be dropped. 432 ++NumRefs; 433 434 // Finally, remove the entry. 435 PointerMap.erase(ValToRemove); 436 } 437 438 // Stop using the alias set, removing it. 439 AS.RefCount -= NumRefs; 440 if (AS.RefCount == 0) 441 AS.removeFromTracker(*this); 442 } 443 444 bool 445 AliasSetTracker::remove(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo) { 446 AliasSet *AS = findAliasSetForPointer(Ptr, Size, AAInfo); 447 if (!AS) return false; 448 remove(*AS); 449 return true; 450 } 451 452 bool AliasSetTracker::remove(LoadInst *LI) { 453 uint64_t Size = AA.getTypeStoreSize(LI->getType()); 454 455 AAMDNodes AAInfo; 456 LI->getAAMetadata(AAInfo); 457 458 AliasSet *AS = findAliasSetForPointer(LI->getOperand(0), Size, AAInfo); 459 if (!AS) return false; 460 remove(*AS); 461 return true; 462 } 463 464 bool AliasSetTracker::remove(StoreInst *SI) { 465 uint64_t Size = AA.getTypeStoreSize(SI->getOperand(0)->getType()); 466 467 AAMDNodes AAInfo; 468 SI->getAAMetadata(AAInfo); 469 470 AliasSet *AS = findAliasSetForPointer(SI->getOperand(1), Size, AAInfo); 471 if (!AS) return false; 472 remove(*AS); 473 return true; 474 } 475 476 bool AliasSetTracker::remove(VAArgInst *VAAI) { 477 AAMDNodes AAInfo; 478 VAAI->getAAMetadata(AAInfo); 479 480 AliasSet *AS = findAliasSetForPointer(VAAI->getOperand(0), 481 AliasAnalysis::UnknownSize, AAInfo); 482 if (!AS) return false; 483 remove(*AS); 484 return true; 485 } 486 487 bool AliasSetTracker::removeUnknown(Instruction *I) { 488 if (!I->mayReadOrWriteMemory()) 489 return false; // doesn't alias anything 490 491 AliasSet *AS = findAliasSetForUnknownInst(I); 492 if (!AS) return false; 493 remove(*AS); 494 return true; 495 } 496 497 bool AliasSetTracker::remove(Instruction *I) { 498 // Dispatch to one of the other remove methods... 499 if (LoadInst *LI = dyn_cast<LoadInst>(I)) 500 return remove(LI); 501 if (StoreInst *SI = dyn_cast<StoreInst>(I)) 502 return remove(SI); 503 if (VAArgInst *VAAI = dyn_cast<VAArgInst>(I)) 504 return remove(VAAI); 505 return removeUnknown(I); 506 } 507 508 509 // deleteValue method - This method is used to remove a pointer value from the 510 // AliasSetTracker entirely. It should be used when an instruction is deleted 511 // from the program to update the AST. If you don't use this, you would have 512 // dangling pointers to deleted instructions. 513 // 514 void AliasSetTracker::deleteValue(Value *PtrVal) { 515 // Notify the alias analysis implementation that this value is gone. 516 AA.deleteValue(PtrVal); 517 518 // If this is a call instruction, remove the callsite from the appropriate 519 // AliasSet (if present). 520 if (Instruction *Inst = dyn_cast<Instruction>(PtrVal)) { 521 if (Inst->mayReadOrWriteMemory()) { 522 // Scan all the alias sets to see if this call site is contained. 523 for (iterator I = begin(), E = end(); I != E;) { 524 iterator Cur = I++; 525 if (!Cur->Forward) 526 Cur->removeUnknownInst(*this, Inst); 527 } 528 } 529 } 530 531 // First, look up the PointerRec for this pointer. 532 PointerMapType::iterator I = PointerMap.find_as(PtrVal); 533 if (I == PointerMap.end()) return; // Noop 534 535 // If we found one, remove the pointer from the alias set it is in. 536 AliasSet::PointerRec *PtrValEnt = I->second; 537 AliasSet *AS = PtrValEnt->getAliasSet(*this); 538 539 // Unlink and delete from the list of values. 540 PtrValEnt->eraseFromList(); 541 542 // Stop using the alias set. 543 AS->dropRef(*this); 544 545 PointerMap.erase(I); 546 } 547 548 // copyValue - This method should be used whenever a preexisting value in the 549 // program is copied or cloned, introducing a new value. Note that it is ok for 550 // clients that use this method to introduce the same value multiple times: if 551 // the tracker already knows about a value, it will ignore the request. 552 // 553 void AliasSetTracker::copyValue(Value *From, Value *To) { 554 // Notify the alias analysis implementation that this value is copied. 555 AA.copyValue(From, To); 556 557 // First, look up the PointerRec for this pointer. 558 PointerMapType::iterator I = PointerMap.find_as(From); 559 if (I == PointerMap.end()) 560 return; // Noop 561 assert(I->second->hasAliasSet() && "Dead entry?"); 562 563 AliasSet::PointerRec &Entry = getEntryFor(To); 564 if (Entry.hasAliasSet()) return; // Already in the tracker! 565 566 // Add it to the alias set it aliases... 567 I = PointerMap.find_as(From); 568 AliasSet *AS = I->second->getAliasSet(*this); 569 AS->addPointer(*this, Entry, I->second->getSize(), 570 I->second->getAAInfo(), 571 true); 572 } 573 574 575 576 //===----------------------------------------------------------------------===// 577 // AliasSet/AliasSetTracker Printing Support 578 //===----------------------------------------------------------------------===// 579 580 void AliasSet::print(raw_ostream &OS) const { 581 OS << " AliasSet[" << (const void*)this << ", " << RefCount << "] "; 582 OS << (AliasTy == MustAlias ? "must" : "may") << " alias, "; 583 switch (AccessTy) { 584 case NoModRef: OS << "No access "; break; 585 case Refs : OS << "Ref "; break; 586 case Mods : OS << "Mod "; break; 587 case ModRef : OS << "Mod/Ref "; break; 588 default: llvm_unreachable("Bad value for AccessTy!"); 589 } 590 if (isVolatile()) OS << "[volatile] "; 591 if (Forward) 592 OS << " forwarding to " << (void*)Forward; 593 594 595 if (!empty()) { 596 OS << "Pointers: "; 597 for (iterator I = begin(), E = end(); I != E; ++I) { 598 if (I != begin()) OS << ", "; 599 I.getPointer()->printAsOperand(OS << "("); 600 OS << ", " << I.getSize() << ")"; 601 } 602 } 603 if (!UnknownInsts.empty()) { 604 OS << "\n " << UnknownInsts.size() << " Unknown instructions: "; 605 for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) { 606 if (i) OS << ", "; 607 UnknownInsts[i]->printAsOperand(OS); 608 } 609 } 610 OS << "\n"; 611 } 612 613 void AliasSetTracker::print(raw_ostream &OS) const { 614 OS << "Alias Set Tracker: " << AliasSets.size() << " alias sets for " 615 << PointerMap.size() << " pointer values.\n"; 616 for (const_iterator I = begin(), E = end(); I != E; ++I) 617 I->print(OS); 618 OS << "\n"; 619 } 620 621 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 622 void AliasSet::dump() const { print(dbgs()); } 623 void AliasSetTracker::dump() const { print(dbgs()); } 624 #endif 625 626 //===----------------------------------------------------------------------===// 627 // ASTCallbackVH Class Implementation 628 //===----------------------------------------------------------------------===// 629 630 void AliasSetTracker::ASTCallbackVH::deleted() { 631 assert(AST && "ASTCallbackVH called with a null AliasSetTracker!"); 632 AST->deleteValue(getValPtr()); 633 // this now dangles! 634 } 635 636 void AliasSetTracker::ASTCallbackVH::allUsesReplacedWith(Value *V) { 637 AST->copyValue(getValPtr(), V); 638 } 639 640 AliasSetTracker::ASTCallbackVH::ASTCallbackVH(Value *V, AliasSetTracker *ast) 641 : CallbackVH(V), AST(ast) {} 642 643 AliasSetTracker::ASTCallbackVH & 644 AliasSetTracker::ASTCallbackVH::operator=(Value *V) { 645 return *this = ASTCallbackVH(V, AST); 646 } 647 648 //===----------------------------------------------------------------------===// 649 // AliasSetPrinter Pass 650 //===----------------------------------------------------------------------===// 651 652 namespace { 653 class AliasSetPrinter : public FunctionPass { 654 AliasSetTracker *Tracker; 655 public: 656 static char ID; // Pass identification, replacement for typeid 657 AliasSetPrinter() : FunctionPass(ID) { 658 initializeAliasSetPrinterPass(*PassRegistry::getPassRegistry()); 659 } 660 661 void getAnalysisUsage(AnalysisUsage &AU) const override { 662 AU.setPreservesAll(); 663 AU.addRequired<AliasAnalysis>(); 664 } 665 666 bool runOnFunction(Function &F) override { 667 Tracker = new AliasSetTracker(getAnalysis<AliasAnalysis>()); 668 669 for (inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I) 670 Tracker->add(&*I); 671 Tracker->print(errs()); 672 delete Tracker; 673 return false; 674 } 675 }; 676 } 677 678 char AliasSetPrinter::ID = 0; 679 INITIALIZE_PASS_BEGIN(AliasSetPrinter, "print-alias-sets", 680 "Alias Set Printer", false, true) 681 INITIALIZE_AG_DEPENDENCY(AliasAnalysis) 682 INITIALIZE_PASS_END(AliasSetPrinter, "print-alias-sets", 683 "Alias Set Printer", false, true) 684