Loads.cpp File Reference

#include "llvm/Analysis/Loads.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumeBundleQueries.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/MemoryLocation.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"

Go to the source code of this file.

Functions
static bool	isAligned (const Value *Base, const APInt &Offset, Align Alignment, const DataLayout &DL)
static bool	isDereferenceableAndAlignedPointer (const Value *V, Align Alignment, const APInt &Size, const DataLayout &DL, const Instruction *CtxI, AssumptionCache *AC, const DominatorTree *DT, const TargetLibraryInfo *TLI, SmallPtrSetImpl< const Value * > &Visited, unsigned MaxDepth)
	Test if V is always a pointer to allocated and suitably aligned memory for a simple load or store.
static bool	AreEquivalentAddressValues (const Value *A, const Value *B)
	Test if A and B will obviously have the same value.
static bool	areNonOverlapSameBaseLoadAndStore (const Value *LoadPtr, Type *LoadTy, const Value *StorePtr, Type *StoreTy, const DataLayout &DL)
static Value *	getAvailableLoadStore (Instruction *Inst, const Value *Ptr, Type *AccessTy, bool AtLeastAtomic, const DataLayout &DL, bool *IsLoadCSE)

Function Documentation

AreEquivalentAddressValues()

static bool AreEquivalentAddressValues ( const Value *  A, const Value *  B  )

static

Test if A and B will obviously have the same value.

This includes recognizing that t0 and t1 will have the same value in code like this:

%t0 = getelementptr \@a, 0, 3
store i32 0, i32* %t0
%t1 = getelementptr \@a, 0, 3
%t2 = load i32* %t1

Definition at line 240 of file Loads.cpp.

References A, and B.

Referenced by getAvailableLoadStore(), and llvm::isSafeToLoadUnconditionally().

areNonOverlapSameBaseLoadAndStore()

static bool areNonOverlapSameBaseLoadAndStore ( const Value *  LoadPtr, Type *  LoadTy, const Value *  StorePtr, Type *  StoreTy, const DataLayout &  DL  )

static

Definition at line 471 of file Loads.cpp.

References DL, llvm::Value::getType(), llvm::ConstantRange::intersectWith(), llvm::ConstantRange::isEmptySet(), llvm::LocationSize::precise(), and llvm::Value::stripAndAccumulateConstantOffsets().

Referenced by llvm::findAvailablePtrLoadStore().

getAvailableLoadStore()

static Value * getAvailableLoadStore ( Instruction *  Inst, const Value *  Ptr, Type *  AccessTy, bool  AtLeastAtomic, const DataLayout &  DL, bool *  IsLoadCSE  )

static

Definition at line 493 of file Loads.cpp.

References AreEquivalentAddressValues(), llvm::CallingConv::C, llvm::ConstantFoldLoadFromConst(), DL, llvm::ConstantInt::get(), llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::getFixedValue(), llvm::APInt::getSplat(), llvm::ConstantInt::getType(), llvm::Value::getType(), llvm::CastInst::isBitOrNoopPointerCastable(), llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::isScalable(), Ptr, llvm::Splat, and llvm::Value::stripPointerCasts().

Referenced by llvm::FindAvailableLoadedValue(), and llvm::findAvailablePtrLoadStore().

isAligned()

static bool isAligned ( const Value *  Base, const APInt &  Offset, Align  Alignment, const DataLayout &  DL  )

static

Definition at line 29 of file Loads.cpp.

References llvm::sampleprof::Base, DL, and llvm::Offset.

Referenced by isDereferenceableAndAlignedPointer().

isDereferenceableAndAlignedPointer()

static bool isDereferenceableAndAlignedPointer ( const Value *  V, Align  Alignment, const APInt &  Size, const DataLayout &  DL, const Instruction *  CtxI, AssumptionCache *  AC, const DominatorTree *  DT, const TargetLibraryInfo *  TLI, SmallPtrSetImpl< const Value * > &  Visited, unsigned  MaxDepth  )

static

Test if V is always a pointer to allocated and suitably aligned memory for a simple load or store.

TODO refactor this function to be able to search independently for Dereferencability and Alignment requirements.

Look through assumes to see if both dereferencability and alignment can be provent by an assume

Definition at line 37 of file Loads.cpp.

References llvm::RetainedKnowledge::ArgValue, assert(), llvm::sampleprof::Base, DL, GEP, llvm::getArgumentAliasingToReturnedPointer(), llvm::APInt::getBoolValue(), llvm::getKnowledgeForValue(), llvm::getObjectSize(), if(), llvm::SmallPtrSetImpl< PtrType >::insert(), isAligned(), isDereferenceableAndAlignedPointer(), llvm::isKnownNonZero(), llvm::isValidAssumeForContext(), MaxDepth, llvm::ObjectSizeOpts::NullIsUnknownSize, llvm::Offset, llvm::ObjectSizeOpts::RoundToAlign, Size, llvm::APInt::uge(), and llvm::Align::value().

Referenced by llvm::canReplacePointersIfEqual(), llvm::isDereferenceableAndAlignedInLoop(), isDereferenceableAndAlignedPointer(), llvm::isDereferenceableAndAlignedPointer(), llvm::isDereferenceablePointer(), and llvm::isSafeToLoadUnconditionally().