X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FScalarEvolutionAliasAnalysis.cpp;h=2e50c80c4e731bb1ea3ff9ca3ab0da7cf3bdaea5;hb=15465ea1a2de1290e7a4f695a5d57039f7c76796;hp=58d3322683a94bee809456363a657d35fbb17b53;hpb=0293ed6a0604ff16c06218ea7486fd9b2e8bebf7;p=oota-llvm.git diff --git a/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp b/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp index 58d3322683a..2e50c80c4e7 100644 --- a/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp +++ b/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp @@ -20,66 +20,20 @@ //===----------------------------------------------------------------------===// #include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h" +#include "llvm/Analysis/TargetLibraryInfo.h" using namespace llvm; -// Register this pass... -char ScalarEvolutionAliasAnalysis::ID = 0; -INITIALIZE_AG_PASS_BEGIN(ScalarEvolutionAliasAnalysis, AliasAnalysis, "scev-aa", - "ScalarEvolution-based Alias Analysis", false, true, - false) -INITIALIZE_PASS_DEPENDENCY(ScalarEvolution) -INITIALIZE_AG_PASS_END(ScalarEvolutionAliasAnalysis, AliasAnalysis, "scev-aa", - "ScalarEvolution-based Alias Analysis", false, true, - false) - -FunctionPass *llvm::createScalarEvolutionAliasAnalysisPass() { - return new ScalarEvolutionAliasAnalysis(); -} - -void ScalarEvolutionAliasAnalysis::getAnalysisUsage(AnalysisUsage &AU) const { - AU.addRequiredTransitive(); - AU.setPreservesAll(); - AliasAnalysis::getAnalysisUsage(AU); -} - -bool ScalarEvolutionAliasAnalysis::runOnFunction(Function &F) { - InitializeAliasAnalysis(this, &F.getParent()->getDataLayout()); - SE = &getAnalysis(); - return false; -} - -/// Given an expression, try to find a base value. -/// -/// Returns null if none was found. -Value *ScalarEvolutionAliasAnalysis::GetBaseValue(const SCEV *S) { - if (const SCEVAddRecExpr *AR = dyn_cast(S)) { - // In an addrec, assume that the base will be in the start, rather - // than the step. - return GetBaseValue(AR->getStart()); - } else if (const SCEVAddExpr *A = dyn_cast(S)) { - // If there's a pointer operand, it'll be sorted at the end of the list. - const SCEV *Last = A->getOperand(A->getNumOperands() - 1); - if (Last->getType()->isPointerTy()) - return GetBaseValue(Last); - } else if (const SCEVUnknown *U = dyn_cast(S)) { - // This is a leaf node. - return U->getValue(); - } - // No Identified object found. - return nullptr; -} - -AliasResult ScalarEvolutionAliasAnalysis::alias(const MemoryLocation &LocA, - const MemoryLocation &LocB) { +AliasResult SCEVAAResult::alias(const MemoryLocation &LocA, + const MemoryLocation &LocB) { // If either of the memory references is empty, it doesn't matter what the // pointer values are. This allows the code below to ignore this special // case. if (LocA.Size == 0 || LocB.Size == 0) return NoAlias; - // This is ScalarEvolutionAliasAnalysis. Get the SCEVs! - const SCEV *AS = SE->getSCEV(const_cast(LocA.Ptr)); - const SCEV *BS = SE->getSCEV(const_cast(LocB.Ptr)); + // This is SCEVAAResult. Get the SCEVs! + const SCEV *AS = SE.getSCEV(const_cast(LocA.Ptr)); + const SCEV *BS = SE.getSCEV(const_cast(LocB.Ptr)); // If they evaluate to the same expression, it's a MustAlias. if (AS == BS) @@ -87,20 +41,20 @@ AliasResult ScalarEvolutionAliasAnalysis::alias(const MemoryLocation &LocA, // If something is known about the difference between the two addresses, // see if it's enough to prove a NoAlias. - if (SE->getEffectiveSCEVType(AS->getType()) == - SE->getEffectiveSCEVType(BS->getType())) { - unsigned BitWidth = SE->getTypeSizeInBits(AS->getType()); + if (SE.getEffectiveSCEVType(AS->getType()) == + SE.getEffectiveSCEVType(BS->getType())) { + unsigned BitWidth = SE.getTypeSizeInBits(AS->getType()); APInt ASizeInt(BitWidth, LocA.Size); APInt BSizeInt(BitWidth, LocB.Size); // Compute the difference between the two pointers. - const SCEV *BA = SE->getMinusSCEV(BS, AS); + const SCEV *BA = SE.getMinusSCEV(BS, AS); // Test whether the difference is known to be great enough that memory of // the given sizes don't overlap. This assumes that ASizeInt and BSizeInt // are non-zero, which is special-cased above. - if (ASizeInt.ule(SE->getUnsignedRange(BA).getUnsignedMin()) && - (-BSizeInt).uge(SE->getUnsignedRange(BA).getUnsignedMax())) + if (ASizeInt.ule(SE.getUnsignedRange(BA).getUnsignedMin()) && + (-BSizeInt).uge(SE.getUnsignedRange(BA).getUnsignedMax())) return NoAlias; // Folding the subtraction while preserving range information can be tricky @@ -108,13 +62,13 @@ AliasResult ScalarEvolutionAliasAnalysis::alias(const MemoryLocation &LocA, // and try again to see if things fold better that way. // Compute the difference between the two pointers. - const SCEV *AB = SE->getMinusSCEV(AS, BS); + const SCEV *AB = SE.getMinusSCEV(AS, BS); // Test whether the difference is known to be great enough that memory of // the given sizes don't overlap. This assumes that ASizeInt and BSizeInt // are non-zero, which is special-cased above. - if (BSizeInt.ule(SE->getUnsignedRange(AB).getUnsignedMin()) && - (-ASizeInt).uge(SE->getUnsignedRange(AB).getUnsignedMax())) + if (BSizeInt.ule(SE.getUnsignedRange(AB).getUnsignedMin()) && + (-ASizeInt).uge(SE.getUnsignedRange(AB).getUnsignedMax())) return NoAlias; } @@ -133,5 +87,62 @@ AliasResult ScalarEvolutionAliasAnalysis::alias(const MemoryLocation &LocA, return NoAlias; // Forward the query to the next analysis. - return AliasAnalysis::alias(LocA, LocB); + return AAResultBase::alias(LocA, LocB); +} + +/// Given an expression, try to find a base value. +/// +/// Returns null if none was found. +Value *SCEVAAResult::GetBaseValue(const SCEV *S) { + if (const SCEVAddRecExpr *AR = dyn_cast(S)) { + // In an addrec, assume that the base will be in the start, rather + // than the step. + return GetBaseValue(AR->getStart()); + } else if (const SCEVAddExpr *A = dyn_cast(S)) { + // If there's a pointer operand, it'll be sorted at the end of the list. + const SCEV *Last = A->getOperand(A->getNumOperands() - 1); + if (Last->getType()->isPointerTy()) + return GetBaseValue(Last); + } else if (const SCEVUnknown *U = dyn_cast(S)) { + // This is a leaf node. + return U->getValue(); + } + // No Identified object found. + return nullptr; +} + +SCEVAAResult SCEVAA::run(Function &F, AnalysisManager *AM) { + return SCEVAAResult(AM->getResult(F), + AM->getResult(F)); +} + +char SCEVAA::PassID; + +char SCEVAAWrapperPass::ID = 0; +INITIALIZE_PASS_BEGIN(SCEVAAWrapperPass, "scev-aa", + "ScalarEvolution-based Alias Analysis", false, true) +INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass) +INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) +INITIALIZE_PASS_END(SCEVAAWrapperPass, "scev-aa", + "ScalarEvolution-based Alias Analysis", false, true) + +FunctionPass *llvm::createSCEVAAWrapperPass() { + return new SCEVAAWrapperPass(); +} + +SCEVAAWrapperPass::SCEVAAWrapperPass() : FunctionPass(ID) { + initializeSCEVAAWrapperPassPass(*PassRegistry::getPassRegistry()); +} + +bool SCEVAAWrapperPass::runOnFunction(Function &F) { + Result.reset( + new SCEVAAResult(getAnalysis().getTLI(), + getAnalysis().getSE())); + return false; +} + +void SCEVAAWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const { + AU.setPreservesAll(); + AU.addRequired(); + AU.addRequired(); }