#include <AliasAnalysis.h>

Inheritance diagram for llvm::AliasAnalysis:

Collaboration diagram for llvm::AliasAnalysis:

Classes
struct	Location
	Location - A description of a memory location. More...

Public Types
enum	AliasResult { NoAlias = 0, MayAlias, PartialAlias, MustAlias }

enum	ModRefResult { NoModRef = 0, Ref = 1, Mod = 2, ModRef = 3 }

enum	{ Nowhere = 0, ArgumentPointees = 4, Anywhere = 8 \| ArgumentPointees }

enum	ModRefBehavior { DoesNotAccessMemory = Nowhere \| NoModRef, OnlyReadsArgumentPointees = ArgumentPointees \| Ref, OnlyAccessesArgumentPointees = ArgumentPointees \| ModRef, OnlyReadsMemory = Anywhere \| Ref, UnknownModRefBehavior = Anywhere \| ModRef }

Public Member Functions
	AliasAnalysis ()

virtual	~AliasAnalysis ()

const DataLayout *	getDataLayout () const

const TargetLibraryInfo *	getTargetLibraryInfo () const

uint64_t	getTypeStoreSize (Type *Ty)

Location	getLocation (const LoadInst *LI)

Location	getLocation (const StoreInst *SI)

Location	getLocation (const VAArgInst *VI)

Location	getLocation (const AtomicCmpXchgInst *CXI)

Location	getLocation (const AtomicRMWInst *RMWI)

virtual AliasResult	alias (const Location &LocA, const Location &LocB)

AliasResult	alias (const Value V1, uint64_t V1Size, const Value V2, uint64_t V2Size)
	alias - A convenience wrapper. More...

AliasResult	alias (const Value V1, const Value V2)
	alias - A convenience wrapper. More...

bool	isNoAlias (const Location &LocA, const Location &LocB)

bool	isNoAlias (const Value V1, uint64_t V1Size, const Value V2, uint64_t V2Size)
	isNoAlias - A convenience wrapper. More...

bool	isNoAlias (const Value V1, const Value V2)
	isNoAlias - A convenience wrapper. More...

bool	isMustAlias (const Location &LocA, const Location &LocB)
	isMustAlias - A convenience wrapper. More...

bool	isMustAlias (const Value V1, const Value V2)
	isMustAlias - A convenience wrapper. More...

virtual bool	pointsToConstantMemory (const Location &Loc, bool OrLocal=false)

bool	pointsToConstantMemory (const Value *P, bool OrLocal=false)
	pointsToConstantMemory - A convenient wrapper. More...

virtual ModRefBehavior	getModRefBehavior (ImmutableCallSite CS)
	getModRefBehavior - Return the behavior when calling the given call site. More...

virtual ModRefBehavior	getModRefBehavior (const Function *F)

bool	doesNotAccessMemory (ImmutableCallSite CS)

bool	doesNotAccessMemory (const Function *F)

bool	onlyReadsMemory (ImmutableCallSite CS)

bool	onlyReadsMemory (const Function *F)

ModRefResult	getModRefInfo (const Instruction *I, const Location &Loc)

ModRefResult	getModRefInfo (const Instruction I, const Value P, uint64_t Size)
	getModRefInfo - A convenience wrapper. More...

virtual ModRefResult	getModRefInfo (ImmutableCallSite CS, const Location &Loc)

ModRefResult	getModRefInfo (ImmutableCallSite CS, const Value *P, uint64_t Size)
	getModRefInfo (for call sites) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const CallInst *C, const Location &Loc)

ModRefResult	getModRefInfo (const CallInst C, const Value P, uint64_t Size)
	getModRefInfo (for calls) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const InvokeInst *I, const Location &Loc)

ModRefResult	getModRefInfo (const InvokeInst I, const Value P, uint64_t Size)
	getModRefInfo (for invokes) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const LoadInst *L, const Location &Loc)

ModRefResult	getModRefInfo (const LoadInst L, const Value P, uint64_t Size)
	getModRefInfo (for loads) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const StoreInst *S, const Location &Loc)

ModRefResult	getModRefInfo (const StoreInst S, const Value P, uint64_t Size)
	getModRefInfo (for stores) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const FenceInst *S, const Location &Loc)

ModRefResult	getModRefInfo (const FenceInst S, const Value P, uint64_t Size)
	getModRefInfo (for fences) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const AtomicCmpXchgInst *CX, const Location &Loc)

ModRefResult	getModRefInfo (const AtomicCmpXchgInst CX, const Value P, unsigned Size)
	getModRefInfo (for cmpxchges) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const AtomicRMWInst *RMW, const Location &Loc)

ModRefResult	getModRefInfo (const AtomicRMWInst RMW, const Value P, unsigned Size)
	getModRefInfo (for atomicrmws) - A convenience wrapper. More...

ModRefResult	getModRefInfo (const VAArgInst *I, const Location &Loc)

ModRefResult	getModRefInfo (const VAArgInst I, const Value P, uint64_t Size)
	getModRefInfo (for va_args) - A convenience wrapper. More...

virtual ModRefResult	getModRefInfo (ImmutableCallSite CS1, ImmutableCallSite CS2)

ModRefResult	callCapturesBefore (const Instruction I, const AliasAnalysis::Location &MemLoc, DominatorTree DT)

ModRefResult	callCapturesBefore (const Instruction I, const Value P, uint64_t Size, DominatorTree *DT)
	callCapturesBefore - A convenience wrapper. More...

bool	canBasicBlockModify (const BasicBlock &BB, const Location &Loc)

bool	canBasicBlockModify (const BasicBlock &BB, const Value *P, uint64_t Size)
	canBasicBlockModify - A convenience wrapper. More...

bool	canInstructionRangeModify (const Instruction &I1, const Instruction &I2, const Location &Loc)

bool	canInstructionRangeModify (const Instruction &I1, const Instruction &I2, const Value *Ptr, uint64_t Size)
	canInstructionRangeModify - A convenience wrapper. More...

virtual void	deleteValue (Value *V)

virtual void	copyValue (Value From, Value To)

virtual void	addEscapingUse (Use &U)

void	replaceWithNewValue (Value Old, Value New)

Static Public Member Functions
static Location	getLocationForSource (const MemTransferInst *MTI)

static Location	getLocationForDest (const MemIntrinsic *MI)

static bool	onlyReadsMemory (ModRefBehavior MRB)

static bool	onlyAccessesArgPointees (ModRefBehavior MRB)

static bool	doesAccessArgPointees (ModRefBehavior MRB)

Static Public Attributes
static char	ID = 0

static uint64_t const	UnknownSize = ~UINT64_C(0)

Protected Member Functions
void	InitializeAliasAnalysis (Pass *P)

virtual void	getAnalysisUsage (AnalysisUsage &AU) const

Protected Attributes
const DataLayout *	TD

const TargetLibraryInfo *	TLI

Detailed Description

Definition at line 56 of file AliasAnalysis.h.

Member Enumeration Documentation

anonymous enum

These values define additional bits used to define the ModRefBehavior values.

Enumerator
Nowhere
ArgumentPointees
Anywhere

Definition at line 235 of file AliasAnalysis.h.

enum llvm::AliasAnalysis::AliasResult

Alias analysis result - Either we know for sure that it does not alias, we know for sure it must alias, or we don't know anything: The two pointers might alias. This enum is designed so you can do things like: if (AA.alias(P1, P2)) { ... } to check to see if two pointers might alias.

See docs/AliasAnalysis.html for more information on the specific meanings of these values.

Enumerator
NoAlias	No dependencies.
MayAlias	Anything goes.
PartialAlias	Pointers differ, but pointees overlap.
MustAlias	Pointers are equal.

Definition at line 161 of file AliasAnalysis.h.

enum llvm::AliasAnalysis::ModRefBehavior

ModRefBehavior - Summary of how a function affects memory in the program. Loads from constant globals are not considered memory accesses for this interface. Also, functions may freely modify stack space local to their invocation without having to report it through these interfaces.

Enumerator
DoesNotAccessMemory	DoesNotAccessMemory - This function does not perform any non-local loads or stores to memory. This property corresponds to the GCC 'const' attribute. This property corresponds to the LLVM IR 'readnone' attribute. This property corresponds to the IntrNoMem LLVM intrinsic flag.
OnlyReadsArgumentPointees	OnlyReadsArgumentPointees - The only memory references in this function (if it has any) are non-volatile loads from objects pointed to by its pointer-typed arguments, with arbitrary offsets. This property corresponds to the IntrReadArgMem LLVM intrinsic flag.
OnlyAccessesArgumentPointees	OnlyAccessesArgumentPointees - The only memory references in this function (if it has any) are non-volatile loads and stores from objects pointed to by its pointer-typed arguments, with arbitrary offsets. This property corresponds to the IntrReadWriteArgMem LLVM intrinsic flag.
OnlyReadsMemory	OnlyReadsMemory - This function does not perform any non-local stores or volatile loads, but may read from any memory location. This property corresponds to the GCC 'pure' attribute. This property corresponds to the LLVM IR 'readonly' attribute. This property corresponds to the IntrReadMem LLVM intrinsic flag.
UnknownModRefBehavior	UnknownModRefBehavior - This indicates that the function could not be classified into one of the behaviors above.

Definition at line 241 of file AliasAnalysis.h.

enum llvm::AliasAnalysis::ModRefResult

Simple mod/ref information...ModRefResult - Represent the result of a mod/ref query. Mod and Ref are bits which may be or'd together.

Enumerator
NoModRef
Ref
Mod
ModRef

Definition at line 231 of file AliasAnalysis.h.

Constructor & Destructor Documentation

llvm::AliasAnalysis::AliasAnalysis ( )

inline

Definition at line 78 of file AliasAnalysis.h.

AliasAnalysis::~AliasAnalysis ( )

virtual

Definition at line 469 of file AliasAnalysis.cpp.

Member Function Documentation

void AliasAnalysis::addEscapingUse ( Use & U )

virtual

addEscapingUse - This method should be used whenever an escaping use is added to a pointer value. Analysis implementations may either return conservative responses for that value in the future, or may recompute some or all internal state to continue providing precise responses.

Escaping uses are considered by anything except the following:

GEPs or bitcasts of the pointer
Loads through the pointer
Stores through (but not of) the pointer

Definition at line 73 of file AliasAnalysis.cpp.

References addEscapingUse().

Referenced by addEscapingUse(), and ConstructSSAForLoadSet().

AliasAnalysis::AliasResult AliasAnalysis::alias	(	const Location &	LocA,
		const Location &	LocB
	)

virtual

alias - The main low level interface to the alias analysis implementation. Returns an AliasResult indicating whether the two pointers are aliased to each other. This is the interface that must be implemented by specific alias analysis implementations.

Definition at line 52 of file AliasAnalysis.cpp.

Referenced by alias(), llvm::AliasSet::aliasesPointer(), getModRefInfo(), llvm::MemoryDependenceAnalysis::getPointerDependencyFrom(), isMustAlias(), isNoAlias(), llvm::AliasSet::mergeSetIn(), MIsNeedChainEdge(), and underlyingObjectsAlias().

AliasResult llvm::AliasAnalysis::alias	(	const Value *	V1,
		uint64_t	V1Size,
		const Value *	V2,
		uint64_t	V2Size
	)

inline

alias - A convenience wrapper.

Definition at line 175 of file AliasAnalysis.h.

References alias().

AliasResult llvm::AliasAnalysis::alias	(	const Value *	V1,
		const Value *	V2
	)

inline

alias - A convenience wrapper.

Definition at line 181 of file AliasAnalysis.h.

References alias(), and UnknownSize.

AliasAnalysis::ModRefResult AliasAnalysis::callCapturesBefore	(	const Instruction *	I,
		const AliasAnalysis::Location &	MemLoc,
		DominatorTree *	DT
	)

callCapturesBefore - Return information about whether a particular call site modifies or reads the specified memory location.

Definition at line 416 of file AliasAnalysis.cpp.

References llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::arg_begin(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::arg_end(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::doesNotAccessMemory(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::doesNotCapture(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::getInstruction(), llvm::GetUnderlyingObject(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::isByValArgument(), llvm::isIdentifiedObject(), isNoAlias(), ModRef, NoModRef, llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::onlyReadsMemory(), llvm::PointerMayBeCaptured(), llvm::AliasAnalysis::Location::Ptr, Ref, and TD.

Referenced by callCapturesBefore(), and llvm::MemoryDependenceAnalysis::getPointerDependencyFrom().

ModRefResult llvm::AliasAnalysis::callCapturesBefore	(	const Instruction *	I,
		const Value *	P,
		uint64_t	Size,
		DominatorTree *	DT
	)

inline

callCapturesBefore - A convenience wrapper.

Definition at line 485 of file AliasAnalysis.h.

References callCapturesBefore().

bool AliasAnalysis::canBasicBlockModify	(	const BasicBlock &	BB,
		const Location &	Loc
	)

Higher level methods for querying mod/ref information.canBasicBlockModify - Return true if it is possible for execution of the specified basic block to modify the value pointed to by Ptr.

canBasicBlockModify - Return true if it is possible for execution of the specified basic block to modify the value pointed to by Ptr.

Definition at line 496 of file AliasAnalysis.cpp.

References llvm::BasicBlock::back(), canInstructionRangeModify(), and llvm::BasicBlock::front().

Referenced by canBasicBlockModify().

bool llvm::AliasAnalysis::canBasicBlockModify	(	const BasicBlock &	BB,
		const Value *	P,
		uint64_t	Size
	)

inline

canBasicBlockModify - A convenience wrapper.

Definition at line 499 of file AliasAnalysis.h.

References canBasicBlockModify().

bool AliasAnalysis::canInstructionRangeModify	(	const Instruction &	I1,
		const Instruction &	I2,
		const Location &	Loc
	)

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.

Definition at line 506 of file AliasAnalysis.cpp.

References getModRefInfo(), llvm::Instruction::getParent(), I, and Mod.

Referenced by canBasicBlockModify(), and canInstructionRangeModify().

bool llvm::AliasAnalysis::canInstructionRangeModify	(	const Instruction &	I1,
		const Instruction &	I2,
		const Value *	Ptr,
		uint64_t	Size
	)

inline

canInstructionRangeModify - A convenience wrapper.

Definition at line 511 of file AliasAnalysis.h.

References canInstructionRangeModify().

void AliasAnalysis::copyValue	(	Value *	From,
		Value *	To
	)

virtual

copyValue - This method should be used whenever a preexisting value in the program is copied or cloned, introducing a new value. Note that analysis implementations should tolerate clients that use this method to introduce the same value multiple times: if the analysis already knows about a value, it should ignore the request.

Definition at line 68 of file AliasAnalysis.cpp.

References copyValue().

Referenced by ConstructSSAForLoadSet(), llvm::AliasSetTracker::copyValue(), copyValue(), replaceWithNewValue(), and UpdatePHINodes().

void AliasAnalysis::deleteValue ( Value * V )

virtual

Methods that clients should call when they transform the program to allow alias analyses to update their internal data structures. Note that these methods may be called on any instruction, regardless of whether or not they have pointer-analysis implications.deleteValue - This method should be called whenever an LLVM Value is deleted from the program, for example when an instruction is found to be redundant and is eliminated.

Definition at line 63 of file AliasAnalysis.cpp.

References deleteValue().

Referenced by llvm::AliasSetTracker::deleteValue(), deleteValue(), FindPHIToPartitionLoops(), llvm::FoldSingleEntryPHINodes(), llvm::MemoryDependenceAnalysis::removeInstruction(), and replaceWithNewValue().

static bool llvm::AliasAnalysis::doesAccessArgPointees ( ModRefBehavior MRB )

inlinestatic

doesAccessArgPointees - Return true if functions with the specified behavior are known to potentially read or write from objects pointed to be their pointer-typed arguments (with arbitrary offsets).

Definition at line 346 of file AliasAnalysis.h.

References ArgumentPointees, and ModRef.

Referenced by getModRefInfo().

bool llvm::AliasAnalysis::doesNotAccessMemory ( ImmutableCallSite CS )

inline

doesNotAccessMemory - If the specified call is known to never read or write memory, return true. If the call only reads from known-constant memory, it is also legal to return true. Calls that unwind the stack are legal for this predicate.

Many optimizations (such as CSE and LICM) can be performed on such calls without worrying about aliasing properties, and many calls have this property (e.g. calls to 'sin' and 'cos').

This property corresponds to the GCC 'const' attribute.

Definition at line 295 of file AliasAnalysis.h.

References DoesNotAccessMemory, and getModRefBehavior().

bool llvm::AliasAnalysis::doesNotAccessMemory ( const Function * F )

inline

doesNotAccessMemory - If the specified function is known to never read or write memory, return true. For use when the call site is not known.

Definition at line 302 of file AliasAnalysis.h.

References DoesNotAccessMemory, and getModRefBehavior().

void AliasAnalysis::getAnalysisUsage ( AnalysisUsage & AU ) const

protectedvirtual

getAnalysisUsage - All alias analysis implementations should invoke this directly (using AliasAnalysis::getAnalysisUsage(AU)).

Reimplemented in llvm::LibCallAliasAnalysis.

Definition at line 482 of file AliasAnalysis.cpp.

References llvm::AnalysisUsage::addRequired().

Referenced by llvm::LibCallAliasAnalysis::getAnalysisUsage().

const DataLayout* llvm::AliasAnalysis::getDataLayout ( ) const

inline

getDataLayout - Return a pointer to the current DataLayout object, or null if no DataLayout object is available.

Definition at line 89 of file AliasAnalysis.h.

References TD.

Referenced by getLocForWrite(), getPointerSize(), and isOverwrite().

AliasAnalysis::Location AliasAnalysis::getLocation ( const LoadInst * LI )

getLocation - Fill in Loc with information about the memory reference by the given instruction.

Definition at line 227 of file AliasAnalysis.cpp.

References llvm::Instruction::getMetadata(), llvm::LoadInst::getPointerOperand(), llvm::Value::getType(), getTypeStoreSize(), and llvm::LLVMContext::MD_tbaa.

Referenced by GetLocation(), getLocForWrite(), getModRefInfo(), llvm::MemoryDependenceAnalysis::getPointerDependencyFrom(), and isSafeToMove().

AliasAnalysis::Location AliasAnalysis::getLocation ( const StoreInst * SI )

Definition at line 233 of file AliasAnalysis.cpp.

References llvm::Instruction::getMetadata(), llvm::StoreInst::getPointerOperand(), llvm::Value::getType(), getTypeStoreSize(), llvm::StoreInst::getValueOperand(), and llvm::LLVMContext::MD_tbaa.

AliasAnalysis::Location AliasAnalysis::getLocation ( const VAArgInst * VI )

Definition at line 239 of file AliasAnalysis.cpp.

References llvm::Instruction::getMetadata(), llvm::VAArgInst::getPointerOperand(), llvm::LLVMContext::MD_tbaa, and UnknownSize.

AliasAnalysis::Location AliasAnalysis::getLocation ( const AtomicCmpXchgInst * CXI )

Definition at line 246 of file AliasAnalysis.cpp.

References llvm::AtomicCmpXchgInst::getCompareOperand(), llvm::Instruction::getMetadata(), llvm::AtomicCmpXchgInst::getPointerOperand(), llvm::Value::getType(), getTypeStoreSize(), and llvm::LLVMContext::MD_tbaa.

AliasAnalysis::Location AliasAnalysis::getLocation ( const AtomicRMWInst * RMWI )

Definition at line 253 of file AliasAnalysis.cpp.

References llvm::Instruction::getMetadata(), llvm::AtomicRMWInst::getPointerOperand(), llvm::Value::getType(), getTypeStoreSize(), llvm::AtomicRMWInst::getValOperand(), and llvm::LLVMContext::MD_tbaa.

AliasAnalysis::Location AliasAnalysis::getLocationForDest ( const MemIntrinsic * MI )

static

Definition at line 273 of file AliasAnalysis.cpp.

References llvm::CallingConv::C, llvm::MemIntrinsic::getLength(), llvm::Instruction::getMetadata(), llvm::MemIntrinsic::getRawDest(), llvm::LLVMContext::MD_tbaa, and UnknownSize.

Referenced by getLocForWrite().

AliasAnalysis::Location AliasAnalysis::getLocationForSource ( const MemTransferInst * MTI )

static

Definition at line 260 of file AliasAnalysis.cpp.

References llvm::CallingConv::C, llvm::MemIntrinsic::getLength(), llvm::Instruction::getMetadata(), llvm::MemTransferInst::getRawSource(), llvm::LLVMContext::MD_tbaa, and UnknownSize.

Referenced by getLocForRead().

AliasAnalysis::ModRefBehavior AliasAnalysis::getModRefBehavior ( ImmutableCallSite CS )

virtual

getModRefBehavior - Return the behavior when calling the given call site.

Definition at line 199 of file AliasAnalysis.cpp.

References F(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::getCalledFunction(), getModRefBehavior(), and UnknownModRefBehavior.

Referenced by llvm::objcarc::CanAlterRefCount(), doesNotAccessMemory(), getModRefBehavior(), getModRefInfo(), and onlyReadsMemory().

AliasAnalysis::ModRefBehavior AliasAnalysis::getModRefBehavior ( const Function * F )

virtual

getModRefBehavior - Return the behavior when calling the given function. For use when the call site is not known.

Definition at line 218 of file AliasAnalysis.cpp.

References getModRefBehavior().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const Instruction *	I,
		const Location &	Loc
	)

inline

getModRefInfo - Return information about whether or not an instruction may read or write the specified memory location. An instruction that doesn't read or write memory may be trivially LICM'd for example.

Definition at line 353 of file AliasAnalysis.h.

References llvm::Call, llvm::Instruction::getOpcode(), llvm::SPII::Load, NoModRef, and llvm::SPII::Store.

Referenced by llvm::AliasSet::aliasesPointer(), llvm::AliasSet::aliasesUnknownInst(), canInstructionRangeModify(), llvm::FindAvailableLoadedValue(), llvm::LibCallAliasAnalysis::getModRefInfo(), getModRefInfo(), llvm::MemoryDependenceAnalysis::getPointerDependencyFrom(), isSafeToMove(), and mayLoopAccessLocation().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const Instruction *	I,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo - A convenience wrapper.

Definition at line 371 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	ImmutableCallSite	CS,
		const Location &	Loc
	)

virtual

getModRefInfo (for call sites) - Return information about whether a particular call site modifies or reads the specified memory location.

Reimplemented in llvm::LibCallAliasAnalysis.

Definition at line 80 of file AliasAnalysis.cpp.

References llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::arg_begin(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::arg_end(), doesAccessArgPointees(), DoesNotAccessMemory, llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::getInstruction(), llvm::Instruction::getMetadata(), getModRefBehavior(), getModRefInfo(), llvm::Value::getType(), isNoAlias(), llvm::Type::isPointerTy(), llvm::LLVMContext::MD_tbaa, Mod, ModRef, NoModRef, onlyAccessesArgPointees(), onlyReadsMemory(), pointsToConstantMemory(), Ref, and UnknownSize.

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	ImmutableCallSite	CS,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for call sites) - A convenience wrapper.

Definition at line 382 of file AliasAnalysis.h.

References getModRefInfo().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const CallInst *	C,
		const Location &	Loc
	)

inline

getModRefInfo (for calls) - Return information about whether a particular call modifies or reads the specified memory location.

Definition at line 389 of file AliasAnalysis.h.

References getModRefInfo().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const CallInst *	C,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for calls) - A convenience wrapper.

Definition at line 394 of file AliasAnalysis.h.

References getModRefInfo().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const InvokeInst *	I,
		const Location &	Loc
	)

inline

getModRefInfo (for invokes) - Return information about whether a particular invoke modifies or reads the specified memory location.

Definition at line 400 of file AliasAnalysis.h.

References getModRefInfo().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const InvokeInst *	I,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for invokes) - A convenience wrapper.

Definition at line 406 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	const LoadInst *	L,
		const Location &	Loc
	)

getModRefInfo (for loads) - Return information about whether a particular load modifies or reads the specified memory location.

Definition at line 288 of file AliasAnalysis.cpp.

References alias(), getLocation(), llvm::LoadInst::isUnordered(), ModRef, NoModRef, and Ref.

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const LoadInst *	L,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for loads) - A convenience wrapper.

Definition at line 416 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	const StoreInst *	S,
		const Location &	Loc
	)

getModRefInfo (for stores) - Return information about whether a particular store modifies or reads the specified memory location.

Definition at line 303 of file AliasAnalysis.cpp.

References alias(), getLocation(), llvm::StoreInst::isUnordered(), Mod, ModRef, NoModRef, and pointsToConstantMemory().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const StoreInst *	S,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for stores) - A convenience wrapper.

Definition at line 425 of file AliasAnalysis.h.

References getModRefInfo().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const FenceInst *	S,
		const Location &	Loc
	)

inline

getModRefInfo (for fences) - Return information about whether a particular store modifies or reads the specified memory location.

Definition at line 431 of file AliasAnalysis.h.

References ModRef.

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const FenceInst *	S,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for fences) - A convenience wrapper.

Definition at line 438 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	const AtomicCmpXchgInst *	CX,
		const Location &	Loc
	)

getModRefInfo (for cmpxchges) - Return information about whether a particular cmpxchg modifies or reads the specified memory location.

Definition at line 339 of file AliasAnalysis.cpp.

References alias(), getLocation(), llvm::AtomicCmpXchgInst::getOrdering(), ModRef, llvm::Monotonic, and NoModRef.

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const AtomicCmpXchgInst *	CX,
		const Value *	P,
		unsigned	Size
	)

inline

getModRefInfo (for cmpxchges) - A convenience wrapper.

Definition at line 447 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	const AtomicRMWInst *	RMW,
		const Location &	Loc
	)

getModRefInfo (for atomicrmws) - Return information about whether a particular atomicrmw modifies or reads the specified memory location.

Definition at line 352 of file AliasAnalysis.cpp.

References alias(), getLocation(), llvm::AtomicRMWInst::getOrdering(), ModRef, llvm::Monotonic, and NoModRef.

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const AtomicRMWInst *	RMW,
		const Value *	P,
		unsigned	Size
	)

inline

getModRefInfo (for atomicrmws) - A convenience wrapper.

Definition at line 457 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	const VAArgInst *	I,
		const Location &	Loc
	)

getModRefInfo (for va_args) - Return information about whether a particular va_arg modifies or reads the specified memory location.

Definition at line 323 of file AliasAnalysis.cpp.

References alias(), getLocation(), ModRef, NoModRef, and pointsToConstantMemory().

ModRefResult llvm::AliasAnalysis::getModRefInfo	(	const VAArgInst *	I,
		const Value *	P,
		uint64_t	Size
	)

inline

getModRefInfo (for va_args) - A convenience wrapper.

Definition at line 467 of file AliasAnalysis.h.

References getModRefInfo().

AliasAnalysis::ModRefResult AliasAnalysis::getModRefInfo	(	ImmutableCallSite	CS1,
		ImmutableCallSite	CS2
	)

virtual

getModRefInfo - Return information about whether two call sites may refer to the same set of memory locations. See http://llvm.org/docs/AliasAnalysis.html#ModRefInfo for details.

Reimplemented in llvm::LibCallAliasAnalysis.

Definition at line 126 of file AliasAnalysis.cpp.

References llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::arg_begin(), llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::arg_end(), doesAccessArgPointees(), DoesNotAccessMemory, llvm::CallSiteBase< FunTy, ValTy, UserTy, InstrTy, CallTy, InvokeTy, IterTy >::getInstruction(), llvm::Instruction::getMetadata(), getModRefBehavior(), getModRefInfo(), llvm::Value::getType(), I, llvm::Type::isPointerTy(), llvm::LLVMContext::MD_tbaa, ModRef, NoModRef, onlyAccessesArgPointees(), onlyReadsMemory(), Ref, and UnknownSize.

const TargetLibraryInfo* llvm::AliasAnalysis::getTargetLibraryInfo ( ) const

inline

getTargetLibraryInfo - Return a pointer to the current TargetLibraryInfo object, or null if no TargetLibraryInfo object is available.

Definition at line 94 of file AliasAnalysis.h.

References TLI.

Referenced by GetLocation(), getLocForRead(), llvm::MemoryDependenceAnalysis::getPointerDependencyFrom(), and getPointerSize().

uint64_t AliasAnalysis::getTypeStoreSize ( Type * Ty )

getTypeStoreSize - Return the DataLayout store size for the given type, if known, or a conservative value otherwise.

Definition at line 489 of file AliasAnalysis.cpp.

References llvm::DataLayout::getTypeStoreSize(), TD, and UnknownSize.

Referenced by llvm::AliasSetTracker::add(), llvm::FindAvailableLoadedValue(), getLocation(), llvm::AliasSetTracker::remove(), and underlyingObjectsAlias().

void AliasAnalysis::InitializeAliasAnalysis ( Pass * P )

protected

InitializeAliasAnalysis - Subclasses must call this method to initialize the AliasAnalysis interface before any other methods are called. This is typically called by the run* methods of these subclasses. This may be called multiple times.

InitializeAliasAnalysis - Subclasses must call this method to initialize the AliasAnalysis interface before any other methods are called.

Definition at line 474 of file AliasAnalysis.cpp.

References llvm::Pass::getAnalysis(), llvm::Pass::getAnalysisIfAvailable(), TD, and TLI.

Referenced by llvm::LibCallAliasAnalysis::runOnFunction().

bool llvm::AliasAnalysis::isMustAlias	(	const Location &	LocA,
		const Location &	LocB
	)

inline

isMustAlias - A convenience wrapper.

Definition at line 203 of file AliasAnalysis.h.

References alias(), and MustAlias.

Referenced by llvm::MemoryDependenceAnalysis::getPointerDependencyFrom(), and isPossibleSelfRead().

bool llvm::AliasAnalysis::isMustAlias	(	const Value *	V1,
		const Value *	V2
	)

inline

isMustAlias - A convenience wrapper.

Definition at line 208 of file AliasAnalysis.h.

References alias(), and MustAlias.

bool llvm::AliasAnalysis::isNoAlias	(	const Location &	LocA,
		const Location &	LocB
	)

inline

isNoAlias - A trivial helper function to check to see if the specified pointers are no-alias.

Definition at line 187 of file AliasAnalysis.h.

References alias(), and NoAlias.

Referenced by callCapturesBefore(), getModRefInfo(), isNoAlias(), and isPossibleSelfRead().

bool llvm::AliasAnalysis::isNoAlias	(	const Value *	V1,
		uint64_t	V1Size,
		const Value *	V2,
		uint64_t	V2Size
	)

inline

isNoAlias - A convenience wrapper.

Definition at line 192 of file AliasAnalysis.h.

References isNoAlias().

bool llvm::AliasAnalysis::isNoAlias	(	const Value *	V1,
		const Value *	V2
	)

inline

isNoAlias - A convenience wrapper.

Definition at line 198 of file AliasAnalysis.h.

References isNoAlias().

static bool llvm::AliasAnalysis::onlyAccessesArgPointees ( ModRefBehavior MRB )

inlinestatic

onlyAccessesArgPointees - Return true if functions with the specified behavior are known to read and write at most from objects pointed to by their pointer-typed arguments (with arbitrary offsets).

Definition at line 338 of file AliasAnalysis.h.

References Anywhere, and ArgumentPointees.

Referenced by llvm::objcarc::CanAlterRefCount(), and getModRefInfo().

bool llvm::AliasAnalysis::onlyReadsMemory ( ImmutableCallSite CS )

inline

onlyReadsMemory - If the specified call is known to only read from non-volatile memory (or not access memory at all), return true. Calls that unwind the stack are legal for this predicate.

This property allows many common optimizations to be performed in the absence of interfering store instructions, such as CSE of strlen calls.

This property corresponds to the GCC 'pure' attribute.

Definition at line 315 of file AliasAnalysis.h.

References getModRefBehavior().

Referenced by llvm::objcarc::CanAlterRefCount(), llvm::MemoryDependenceAnalysis::getDependency(), getModRefInfo(), llvm::MemoryDependenceAnalysis::getNonLocalCallDependency(), and onlyReadsMemory().

bool llvm::AliasAnalysis::onlyReadsMemory ( const Function * F )

inline

onlyReadsMemory - If the specified function is known to only read from non-volatile memory (or not access memory at all), return true. For use when the call site is not known.

Definition at line 323 of file AliasAnalysis.h.

References getModRefBehavior(), and onlyReadsMemory().

static bool llvm::AliasAnalysis::onlyReadsMemory ( ModRefBehavior MRB )

inlinestatic

onlyReadsMemory - Return true if functions with the specified behavior are known to only read from non-volatile memory (or not access memory at all).

Definition at line 330 of file AliasAnalysis.h.

References Mod.

bool AliasAnalysis::pointsToConstantMemory	(	const Location &	Loc,
		bool	OrLocal = `false`
	)

virtual

pointsToConstantMemory - If the specified memory location is known to be constant, return true. If OrLocal is true and the specified memory location is known to be "local" (derived from an alloca), return true. Otherwise return false.

Definition at line 57 of file AliasAnalysis.cpp.

References pointsToConstantMemory().

Referenced by getMemCmpLoad(), getModRefInfo(), llvm::MemoryDependenceAnalysis::getPointerDependencyFrom(), llvm::MachineInstr::isInvariantLoad(), llvm::objcarc::IsPotentialRetainableObjPtr(), and pointsToConstantMemory().

bool llvm::AliasAnalysis::pointsToConstantMemory	(	const Value *	P,
		bool	OrLocal = `false`
	)

inline

pointsToConstantMemory - A convenient wrapper.

Definition at line 220 of file AliasAnalysis.h.

References pointsToConstantMemory().

void llvm::AliasAnalysis::replaceWithNewValue	(	Value *	Old,
		Value *	New
	)

inline

replaceWithNewValue - This method is the obvious combination of the two above, and it provided as a helper to simplify client code.

Definition at line 551 of file AliasAnalysis.h.

References copyValue(), and deleteValue().

Member Data Documentation

char AliasAnalysis::ID = 0

static

Definition at line 77 of file AliasAnalysis.h.

Referenced by llvm::LibCallAliasAnalysis::getAdjustedAnalysisPointer().

const DataLayout* llvm::AliasAnalysis::TD

protected

Definition at line 58 of file AliasAnalysis.h.

Referenced by callCapturesBefore(), getDataLayout(), getTypeStoreSize(), and InitializeAliasAnalysis().

const TargetLibraryInfo* llvm::AliasAnalysis::TLI

protected

Definition at line 59 of file AliasAnalysis.h.

Referenced by getTargetLibraryInfo(), and InitializeAliasAnalysis().

uint64_t const llvm::AliasAnalysis::UnknownSize = ~UINT64_C(0)

static

UnknownSize - This is a special value which can be used with the size arguments in alias queries to indicate that the caller does not know the sizes of the potential memory references.

Definition at line 84 of file AliasAnalysis.h.

Referenced by llvm::AliasSetTracker::add(), alias(), getLocation(), getLocationForDest(), getLocationForSource(), getLocForWrite(), getModRefInfo(), getObjectSize(), getPointerSize(), getTypeStoreSize(), isObjectSize(), isObjectSmallerThan(), isOverwrite(), and llvm::AliasSetTracker::remove().

The documentation for this class was generated from the following files:

Classes

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation