X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FAliasAnalysis.cpp;h=73cc9037216a83e7b69f0333ac398c4405817c28;hb=3af7a67629292840f0dbae8fad4e333b009e69dd;hp=912923be8ebd782205b4f57c5da312b16c44a813;hpb=e46a3881fc74652b23c3b31ee487e0ca9a6a268a;p=oota-llvm.git diff --git a/lib/Analysis/AliasAnalysis.cpp b/lib/Analysis/AliasAnalysis.cpp index 912923be8eb..73cc9037216 100644 --- a/lib/Analysis/AliasAnalysis.cpp +++ b/lib/Analysis/AliasAnalysis.cpp @@ -49,9 +49,10 @@ AliasAnalysis::alias(const Location &LocA, const Location &LocB) { return AA->alias(LocA, LocB); } -bool AliasAnalysis::pointsToConstantMemory(const Location &Loc) { +bool AliasAnalysis::pointsToConstantMemory(const Location &Loc, + bool OrLocal) { assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!"); - return AA->pointsToConstantMemory(Loc); + return AA->pointsToConstantMemory(Loc, OrLocal); } void AliasAnalysis::deleteValue(Value *V) { @@ -64,6 +65,12 @@ void AliasAnalysis::copyValue(Value *From, Value *To) { AA->copyValue(From, To); } +void AliasAnalysis::addEscapingUse(Use &U) { + assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!"); + AA->addEscapingUse(U); +} + + AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo(ImmutableCallSite CS, const Location &Loc) { @@ -74,17 +81,25 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS, return NoModRef; ModRefResult Mask = ModRef; - if (MRB == OnlyReadsMemory) + if (onlyReadsMemory(MRB)) Mask = Ref; - else if (MRB == AliasAnalysis::AccessesArguments) { + + if (onlyAccessesArgPointees(MRB)) { bool doesAlias = false; - for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end(); - AI != AE; ++AI) - if (!isNoAlias(Location(*AI), Loc)) { - doesAlias = true; - break; + if (doesAccessArgPointees(MRB)) { + MDNode *CSTag = CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa); + for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end(); + AI != AE; ++AI) { + const Value *Arg = *AI; + if (!Arg->getType()->isPointerTy()) + continue; + Location CSLoc(Arg, UnknownSize, CSTag); + if (!isNoAlias(CSLoc, Loc)) { + doesAlias = true; + break; + } } - + } if (!doesAlias) return NoModRef; } @@ -114,40 +129,55 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2) { if (CS2B == DoesNotAccessMemory) return NoModRef; // If they both only read from memory, there is no dependence. - if (CS1B == OnlyReadsMemory && CS2B == OnlyReadsMemory) + if (onlyReadsMemory(CS1B) && onlyReadsMemory(CS2B)) return NoModRef; AliasAnalysis::ModRefResult Mask = ModRef; // If CS1 only reads memory, the only dependence on CS2 can be // from CS1 reading memory written by CS2. - if (CS1B == OnlyReadsMemory) + if (onlyReadsMemory(CS1B)) Mask = ModRefResult(Mask & Ref); // If CS2 only access memory through arguments, accumulate the mod/ref // information from CS1's references to the memory referenced by // CS2's arguments. - if (CS2B == AccessesArguments) { + if (onlyAccessesArgPointees(CS2B)) { AliasAnalysis::ModRefResult R = NoModRef; - for (ImmutableCallSite::arg_iterator - I = CS2.arg_begin(), E = CS2.arg_end(); I != E; ++I) { - R = ModRefResult((R | getModRefInfo(CS1, *I, UnknownSize)) & Mask); - if (R == Mask) - break; + if (doesAccessArgPointees(CS2B)) { + MDNode *CS2Tag = CS2.getInstruction()->getMetadata(LLVMContext::MD_tbaa); + for (ImmutableCallSite::arg_iterator + I = CS2.arg_begin(), E = CS2.arg_end(); I != E; ++I) { + const Value *Arg = *I; + if (!Arg->getType()->isPointerTy()) + continue; + Location CS2Loc(Arg, UnknownSize, CS2Tag); + R = ModRefResult((R | getModRefInfo(CS1, CS2Loc)) & Mask); + if (R == Mask) + break; + } } return R; } // If CS1 only accesses memory through arguments, check if CS2 references // any of the memory referenced by CS1's arguments. If not, return NoModRef. - if (CS1B == AccessesArguments) { + if (onlyAccessesArgPointees(CS1B)) { AliasAnalysis::ModRefResult R = NoModRef; - for (ImmutableCallSite::arg_iterator - I = CS1.arg_begin(), E = CS1.arg_end(); I != E; ++I) - if (getModRefInfo(CS2, *I, UnknownSize) != NoModRef) { - R = Mask; - break; + if (doesAccessArgPointees(CS1B)) { + MDNode *CS1Tag = CS1.getInstruction()->getMetadata(LLVMContext::MD_tbaa); + for (ImmutableCallSite::arg_iterator + I = CS1.arg_begin(), E = CS1.arg_end(); I != E; ++I) { + const Value *Arg = *I; + if (!Arg->getType()->isPointerTy()) + continue; + Location CS1Loc(Arg, UnknownSize, CS1Tag); + if (getModRefInfo(CS2, CS1Loc) != NoModRef) { + R = Mask; + break; + } } + } if (R == NoModRef) return R; } @@ -176,7 +206,7 @@ AliasAnalysis::getModRefBehavior(ImmutableCallSite CS) { // Otherwise, fall back to the next AA in the chain. But we can merge // in any result we've managed to compute. - return std::min(AA->getModRefBehavior(CS), Min); + return ModRefBehavior(AA->getModRefBehavior(CS) & Min); } AliasAnalysis::ModRefBehavior @@ -189,18 +219,62 @@ AliasAnalysis::getModRefBehavior(const Function *F) { // AliasAnalysis non-virtual helper method implementation //===----------------------------------------------------------------------===// +AliasAnalysis::Location AliasAnalysis::getLocation(const LoadInst *LI) { + return Location(LI->getPointerOperand(), + getTypeStoreSize(LI->getType()), + LI->getMetadata(LLVMContext::MD_tbaa)); +} + +AliasAnalysis::Location AliasAnalysis::getLocation(const StoreInst *SI) { + return Location(SI->getPointerOperand(), + getTypeStoreSize(SI->getValueOperand()->getType()), + SI->getMetadata(LLVMContext::MD_tbaa)); +} + +AliasAnalysis::Location AliasAnalysis::getLocation(const VAArgInst *VI) { + return Location(VI->getPointerOperand(), + UnknownSize, + VI->getMetadata(LLVMContext::MD_tbaa)); +} + + +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 + // to both the source and the destination. + MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa); + + return Location(MTI->getRawSource(), Size, TBAATag); +} + +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 + // to both the source and the destination. + MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa); + + return Location(MTI->getRawDest(), Size, TBAATag); +} + + + AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) { - // Be conservative in the face of volatile. - if (L->isVolatile()) + // Be conservative in the face of volatile/atomic. + if (!L->isUnordered()) return ModRef; // If the load address doesn't alias the given address, it doesn't read // or write the specified memory. - if (!alias(Location(L->getOperand(0), - getTypeStoreSize(L->getType()), - L->getMetadata(LLVMContext::MD_tbaa)), - Loc)) + if (!alias(getLocation(L), Loc)) return NoModRef; // Otherwise, a load just reads. @@ -209,16 +283,13 @@ AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) { AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo(const StoreInst *S, const Location &Loc) { - // Be conservative in the face of volatile. - if (S->isVolatile()) + // Be conservative in the face of volatile/atomic. + if (!S->isUnordered()) return ModRef; // If the store address cannot alias the pointer in question, then the // specified memory cannot be modified by the store. - if (!alias(Location(S->getOperand(1), - getTypeStoreSize(S->getOperand(0)->getType()), - S->getMetadata(LLVMContext::MD_tbaa)), - Loc)) + if (!alias(getLocation(S), Loc)) return NoModRef; // If the pointer is a pointer to constant memory, then it could not have been @@ -234,10 +305,7 @@ AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo(const VAArgInst *V, const Location &Loc) { // If the va_arg address cannot alias the pointer in question, then the // specified memory cannot be accessed by the va_arg. - if (!alias(Location(V->getOperand(0), - UnknownSize, - V->getMetadata(LLVMContext::MD_tbaa)), - Loc)) + if (!alias(getLocation(V), Loc)) return NoModRef; // If the pointer is a pointer to constant memory, then it could not have been @@ -249,13 +317,6 @@ AliasAnalysis::getModRefInfo(const VAArgInst *V, const Location &Loc) { return ModRef; } -AliasAnalysis::ModRefBehavior -AliasAnalysis::getIntrinsicModRefBehavior(unsigned iid) { -#define GET_INTRINSIC_MODREF_BEHAVIOR -#include "llvm/Intrinsics.gen" -#undef GET_INTRINSIC_MODREF_BEHAVIOR -} - // AliasAnalysis destructor: DO NOT move this to the header file for // AliasAnalysis or else clients of the AliasAnalysis class may not depend on // the AliasAnalysis.o file in the current .a file, causing alias analysis @@ -280,7 +341,7 @@ void AliasAnalysis::getAnalysisUsage(AnalysisUsage &AU) const { /// getTypeStoreSize - Return the TargetData store size for the given type, /// if known, or a conservative value otherwise. /// -uint64_t AliasAnalysis::getTypeStoreSize(const Type *Ty) { +uint64_t AliasAnalysis::getTypeStoreSize(Type *Ty) { return TD ? TD->getTypeStoreSize(Ty) : UnknownSize; }