X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FAliasAnalysis.cpp;h=0b0fd50a866f5611ff9eba85fd271674907fe838;hb=b2d414391a6cf361b6e2cb1ad32785e669121b9d;hp=fa1484d57decebbc0608a22533d0157fd02eef22;hpb=43b125912e209e272bc0c9b1eb0253bb373e81b7;p=oota-llvm.git diff --git a/lib/Analysis/AliasAnalysis.cpp b/lib/Analysis/AliasAnalysis.cpp index fa1484d57de..0b0fd50a866 100644 --- a/lib/Analysis/AliasAnalysis.cpp +++ b/lib/Analysis/AliasAnalysis.cpp @@ -27,6 +27,7 @@ #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/Analysis/CFG.h" #include "llvm/Analysis/CaptureTracking.h" +#include "llvm/Analysis/TargetLibraryInfo.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/IR/BasicBlock.h" #include "llvm/IR/DataLayout.h" @@ -37,7 +38,6 @@ #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Type.h" #include "llvm/Pass.h" -#include "llvm/Target/TargetLibraryInfo.h" using namespace llvm; // Register the AliasAnalysis interface, providing a nice name to refer to. @@ -196,12 +196,11 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2) { if (!Arg->getType()->isPointerTy()) continue; ModRefResult ArgMask; - Location CS1Loc = - getArgLocation(CS1, (unsigned) std::distance(CS1.arg_begin(), I), - ArgMask); - // ArgMask indicates what CS1 might do to CS1Loc; if CS1 might Mod - // CS1Loc, then we care about either a Mod or a Ref by CS2. If CS1 - // might Ref, then we care only about a Mod by CS2. + Location CS1Loc = getArgLocation( + CS1, (unsigned)std::distance(CS1.arg_begin(), I), ArgMask); + // ArgMask indicates what CS1 might do to CS1Loc; if CS1 might Mod + // CS1Loc, then we care about either a Mod or a Ref by CS2. If CS1 + // might Ref, then we care only about a Mod by CS2. ModRefResult ArgR = getModRefInfo(CS2, CS1Loc); if (((ArgMask & Mod) != NoModRef && (ArgR & ModRef) != NoModRef) || ((ArgMask & Ref) != NoModRef && (ArgR & Mod) != NoModRef)) @@ -252,61 +251,73 @@ AliasAnalysis::getModRefBehavior(const Function *F) { //===----------------------------------------------------------------------===// AliasAnalysis::Location AliasAnalysis::getLocation(const LoadInst *LI) { + AAMDNodes AATags; + LI->getAAMetadata(AATags); + return Location(LI->getPointerOperand(), - getTypeStoreSize(LI->getType()), - LI->getMetadata(LLVMContext::MD_tbaa)); + getTypeStoreSize(LI->getType()), AATags); } AliasAnalysis::Location AliasAnalysis::getLocation(const StoreInst *SI) { + AAMDNodes AATags; + SI->getAAMetadata(AATags); + return Location(SI->getPointerOperand(), - getTypeStoreSize(SI->getValueOperand()->getType()), - SI->getMetadata(LLVMContext::MD_tbaa)); + getTypeStoreSize(SI->getValueOperand()->getType()), AATags); } AliasAnalysis::Location AliasAnalysis::getLocation(const VAArgInst *VI) { - return Location(VI->getPointerOperand(), - UnknownSize, - VI->getMetadata(LLVMContext::MD_tbaa)); + AAMDNodes AATags; + VI->getAAMetadata(AATags); + + return Location(VI->getPointerOperand(), UnknownSize, AATags); } AliasAnalysis::Location AliasAnalysis::getLocation(const AtomicCmpXchgInst *CXI) { + AAMDNodes AATags; + CXI->getAAMetadata(AATags); + return Location(CXI->getPointerOperand(), getTypeStoreSize(CXI->getCompareOperand()->getType()), - CXI->getMetadata(LLVMContext::MD_tbaa)); + AATags); } AliasAnalysis::Location AliasAnalysis::getLocation(const AtomicRMWInst *RMWI) { + AAMDNodes AATags; + RMWI->getAAMetadata(AATags); + return Location(RMWI->getPointerOperand(), - getTypeStoreSize(RMWI->getValOperand()->getType()), - RMWI->getMetadata(LLVMContext::MD_tbaa)); + getTypeStoreSize(RMWI->getValOperand()->getType()), AATags); } -AliasAnalysis::Location +AliasAnalysis::Location AliasAnalysis::getLocationForSource(const MemTransferInst *MTI) { uint64_t Size = UnknownSize; if (ConstantInt *C = dyn_cast(MTI->getLength())) Size = C->getValue().getZExtValue(); - // memcpy/memmove can have TBAA tags. For memcpy, they apply + // memcpy/memmove can have AA tags. For memcpy, they apply // to both the source and the destination. - MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa); + AAMDNodes AATags; + MTI->getAAMetadata(AATags); - return Location(MTI->getRawSource(), Size, TBAATag); + return Location(MTI->getRawSource(), Size, AATags); } -AliasAnalysis::Location +AliasAnalysis::Location AliasAnalysis::getLocationForDest(const MemIntrinsic *MTI) { uint64_t Size = UnknownSize; if (ConstantInt *C = dyn_cast(MTI->getLength())) Size = C->getValue().getZExtValue(); - // memcpy/memmove can have TBAA tags. For memcpy, they apply + // memcpy/memmove can have AA tags. For memcpy, they apply // to both the source and the destination. - MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa); - - return Location(MTI->getRawDest(), Size, TBAATag); + AAMDNodes AATags; + MTI->getAAMetadata(AATags); + + return Location(MTI->getRawDest(), Size, AATags); } @@ -388,53 +399,6 @@ AliasAnalysis::getModRefInfo(const AtomicRMWInst *RMW, const Location &Loc) { return ModRef; } -namespace { - /// Only find pointer captures which happen before the given instruction. Uses - /// the dominator tree to determine whether one instruction is before another. - /// Only support the case where the Value is defined in the same basic block - /// as the given instruction and the use. - struct CapturesBefore : public CaptureTracker { - CapturesBefore(const Instruction *I, DominatorTree *DT) - : BeforeHere(I), DT(DT), Captured(false) {} - - void tooManyUses() override { Captured = true; } - - bool shouldExplore(const Use *U) override { - Instruction *I = cast(U->getUser()); - BasicBlock *BB = I->getParent(); - // We explore this usage only if the usage can reach "BeforeHere". - // If use is not reachable from entry, there is no need to explore. - if (BeforeHere != I && !DT->isReachableFromEntry(BB)) - return false; - // If the value is defined in the same basic block as use and BeforeHere, - // there is no need to explore the use if BeforeHere dominates use. - // Check whether there is a path from I to BeforeHere. - if (BeforeHere != I && DT->dominates(BeforeHere, I) && - !isPotentiallyReachable(I, BeforeHere, DT)) - return false; - return true; - } - - bool captured(const Use *U) override { - Instruction *I = cast(U->getUser()); - BasicBlock *BB = I->getParent(); - // Same logic as in shouldExplore. - if (BeforeHere != I && !DT->isReachableFromEntry(BB)) - return false; - if (BeforeHere != I && DT->dominates(BeforeHere, I) && - !isPotentiallyReachable(I, BeforeHere, DT)) - return false; - Captured = true; - return true; - } - - const Instruction *BeforeHere; - DominatorTree *DT; - - bool Captured; - }; -} - // FIXME: this is really just shoring-up a deficiency in alias analysis. // BasicAA isn't willing to spend linear time determining whether an alloca // was captured before or after this particular call, while we are. However, @@ -443,9 +407,10 @@ AliasAnalysis::ModRefResult AliasAnalysis::callCapturesBefore(const Instruction *I, const AliasAnalysis::Location &MemLoc, DominatorTree *DT) { - if (!DT || !DL) return AliasAnalysis::ModRef; + if (!DT) + return AliasAnalysis::ModRef; - const Value *Object = GetUnderlyingObject(MemLoc.Ptr, DL); + const Value *Object = GetUnderlyingObject(MemLoc.Ptr, *DL); if (!isIdentifiedObject(Object) || isa(Object) || isa(Object)) return AliasAnalysis::ModRef; @@ -454,9 +419,9 @@ AliasAnalysis::callCapturesBefore(const Instruction *I, if (!CS.getInstruction() || CS.getInstruction() == Object) return AliasAnalysis::ModRef; - CapturesBefore CB(I, DT); - llvm::PointerMayBeCaptured(Object, &CB); - if (CB.Captured) + if (llvm::PointerMayBeCapturedBefore(Object, /* ReturnCaptures */ true, + /* StoreCaptures */ true, I, DT, + /* include Object */ true)) return AliasAnalysis::ModRef; unsigned ArgNo = 0; @@ -475,7 +440,7 @@ AliasAnalysis::callCapturesBefore(const Instruction *I, // assume that the call could touch the pointer, even though it doesn't // escape. if (isNoAlias(AliasAnalysis::Location(*CI), - AliasAnalysis::Location(Object))) + AliasAnalysis::Location(Object))) continue; if (CS.doesNotAccessMemory(ArgNo)) continue; @@ -498,10 +463,10 @@ AliasAnalysis::~AliasAnalysis() {} /// InitializeAliasAnalysis - Subclasses must call this method to initialize the /// AliasAnalysis interface before any other methods are called. /// -void AliasAnalysis::InitializeAliasAnalysis(Pass *P) { - DataLayoutPass *DLP = P->getAnalysisIfAvailable(); - DL = DLP ? &DLP->getDataLayout() : nullptr; - TLI = P->getAnalysisIfAvailable(); +void AliasAnalysis::InitializeAliasAnalysis(Pass *P, const DataLayout *NewDL) { + DL = NewDL; + auto *TLIP = P->getAnalysisIfAvailable(); + TLI = TLIP ? &TLIP->getTLI() : nullptr; AA = &P->getAnalysis(); } @@ -519,21 +484,22 @@ uint64_t AliasAnalysis::getTypeStoreSize(Type *Ty) { } /// canBasicBlockModify - Return true if it is possible for execution of the -/// specified basic block to modify the value pointed to by Ptr. +/// specified basic block to modify the location Loc. /// bool AliasAnalysis::canBasicBlockModify(const BasicBlock &BB, const Location &Loc) { - return canInstructionRangeModify(BB.front(), BB.back(), Loc); + return canInstructionRangeModRef(BB.front(), BB.back(), Loc, Mod); } -/// canInstructionRangeModify - Return true if it is possible for the execution -/// of the specified instructions to modify the value pointed to by Ptr. The -/// instructions to consider are all of the instructions in the range of [I1,I2] -/// INCLUSIVE. I1 and I2 must be in the same basic block. -/// -bool AliasAnalysis::canInstructionRangeModify(const Instruction &I1, +/// canInstructionRangeModRef - Return true if it is possible for the +/// execution of the specified instructions to mod\ref (according to the +/// mode) the location Loc. The instructions to consider are all +/// of the instructions in the range of [I1,I2] INCLUSIVE. +/// I1 and I2 must be in the same basic block. +bool AliasAnalysis::canInstructionRangeModRef(const Instruction &I1, const Instruction &I2, - const Location &Loc) { + const Location &Loc, + const ModRefResult Mode) { assert(I1.getParent() == I2.getParent() && "Instructions not in same basic block!"); BasicBlock::const_iterator I = &I1; @@ -541,7 +507,7 @@ bool AliasAnalysis::canInstructionRangeModify(const Instruction &I1, ++E; // Convert from inclusive to exclusive range. for (; I != E; ++I) // Check every instruction in range - if (getModRefInfo(I, Loc) & Mod) + if (getModRefInfo(I, Loc) & Mode) return true; return false; } @@ -592,4 +558,3 @@ bool llvm::isIdentifiedFunctionLocal(const Value *V) { return isa(V) || isNoAliasCall(V) || isNoAliasArgument(V); } -