#include <Constant.h>

Inheritance diagram for llvm::Constant:

Collaboration diagram for llvm::Constant:

Public Types
enum	PossibleRelocationsTy { NoRelocation = 0, LocalRelocation = 1, GlobalRelocations = 2 }

Public Types inherited from llvm::User
typedef Use *	op_iterator

typedef const Use *	const_op_iterator

Public Types inherited from llvm::Value
enum	ValueTy { ArgumentVal, BasicBlockVal, FunctionVal, GlobalAliasVal, GlobalVariableVal, UndefValueVal, BlockAddressVal, ConstantExprVal, ConstantAggregateZeroVal, ConstantDataArrayVal, ConstantDataVectorVal, ConstantIntVal, ConstantFPVal, ConstantArrayVal, ConstantStructVal, ConstantVectorVal, ConstantPointerNullVal, MDNodeVal, MDStringVal, InlineAsmVal, PseudoSourceValueVal, FixedStackPseudoSourceValueVal, InstructionVal, ConstantFirstVal = FunctionVal, ConstantLastVal = ConstantPointerNullVal }

typedef value_use_iterator< User >	use_iterator

typedef value_use_iterator < const User >	const_use_iterator

Public Member Functions
bool	isNullValue () const

bool	isAllOnesValue () const

bool	isNegativeZeroValue () const

bool	isZeroValue () const
	Return true if the value is negative zero or null value. More...

bool	canTrap () const

bool	isThreadDependent () const
	isThreadDependent - Return true if the value can vary between threads. More...

bool	isConstantUsed () const

PossibleRelocationsTy	getRelocationInfo () const

Constant *	getAggregateElement (unsigned Elt) const

Constant *	getAggregateElement (Constant *Elt) const

Constant *	getSplatValue () const

const APInt &	getUniqueInteger () const

virtual void	destroyConstant ()

virtual void	replaceUsesOfWithOnConstant (Value , Value , Use *)

void	removeDeadConstantUsers () const

Public Member Functions inherited from llvm::User
	~User ()

void	operator delete (void *Usr)
	operator delete - free memory allocated for User and Use objects More...

void	operator delete (void *, unsigned)
	placement delete - required by std, but never called. More...

void	operator delete (void *, unsigned, bool)
	placement delete - required by std, but never called. More...

Value *	getOperand (unsigned i) const

void	setOperand (unsigned i, Value *Val)

const Use &	getOperandUse (unsigned i) const

Use &	getOperandUse (unsigned i)

unsigned	getNumOperands () const

op_iterator	op_begin ()

const_op_iterator	op_begin () const

op_iterator	op_end ()

const_op_iterator	op_end () const

value_op_iterator	value_op_begin ()

value_op_iterator	value_op_end ()

void	dropAllReferences ()

void	replaceUsesOfWith (Value From, Value To)

Public Member Functions inherited from llvm::Value
virtual	~Value ()

void	dump () const
	dump - Support for debugging, callable in GDB: V->dump() More...

void	print (raw_ostream &O, AssemblyAnnotationWriter *AAW=0) const

Type *	getType () const

LLVMContext &	getContext () const
	All values hold a context through their type. More...

bool	hasName () const

ValueName *	getValueName () const

void	setValueName (ValueName *VN)

StringRef	getName () const

void	setName (const Twine &Name)

void	takeName (Value *V)

void	replaceAllUsesWith (Value *V)

bool	use_empty () const

use_iterator	use_begin ()

const_use_iterator	use_begin () const

use_iterator	use_end ()

const_use_iterator	use_end () const

User *	use_back ()

const User *	use_back () const

bool	hasOneUse () const

bool	hasNUses (unsigned N) const

bool	hasNUsesOrMore (unsigned N) const

bool	isUsedInBasicBlock (const BasicBlock *BB) const

unsigned	getNumUses () const

void	addUse (Use &U)

unsigned	getValueID () const

unsigned	getRawSubclassOptionalData () const

void	clearSubclassOptionalData ()

bool	hasSameSubclassOptionalData (const Value *V) const

void	intersectOptionalDataWith (const Value *V)

bool	hasValueHandle () const

Value *	stripPointerCasts ()
	Strips off any unneeded pointer casts, all-zero GEPs and aliases from the specified value, returning the original uncasted value. More...

const Value *	stripPointerCasts () const

Value *	stripPointerCastsNoFollowAliases ()
	Strips off any unneeded pointer casts and all-zero GEPs from the specified value, returning the original uncasted value. More...

const Value *	stripPointerCastsNoFollowAliases () const

Value *	stripInBoundsConstantOffsets ()
	Strips off unneeded pointer casts and all-constant GEPs from the specified value, returning the original pointer value. More...

const Value *	stripInBoundsConstantOffsets () const

Value *	stripAndAccumulateInBoundsConstantOffsets (const DataLayout &DL, APInt &Offset)
	Strips like `stripInBoundsConstantOffsets` but also accumulates the constant offset stripped. More...

const Value *	stripAndAccumulateInBoundsConstantOffsets (const DataLayout &DL, APInt &Offset) const

Value *	stripInBoundsOffsets ()
	Strips off unneeded pointer casts and any in-bounds offsets from the specified value, returning the original pointer value. More...

const Value *	stripInBoundsOffsets () const

bool	isDereferenceablePointer () const

Value *	DoPHITranslation (const BasicBlock CurBB, const BasicBlock PredBB)

const Value *	DoPHITranslation (const BasicBlock CurBB, const BasicBlock PredBB) const

void	mutateType (Type *Ty)

Static Public Member Functions
static bool	classof (const Value *V)

static Constant *	getNullValue (Type *Ty)

static Constant *	getAllOnesValue (Type *Ty)
	Get the all ones value. More...

static Constant *	getIntegerValue (Type *Ty, const APInt &V)

Static Public Member Functions inherited from llvm::User
static bool	classof (const Value *V)

Protected Member Functions
	Constant (Type ty, ValueTy vty, Use Ops, unsigned NumOps)

void	destroyConstantImpl ()

Protected Member Functions inherited from llvm::User
void *	operator new (size_t s, unsigned Us)

	User (Type ty, unsigned vty, Use OpList, unsigned NumOps)

Use *	allocHungoffUses (unsigned) const

void	dropHungoffUses ()

template<int Idx>
Use &	Op ()

template<int Idx>
const Use &	Op () const

Protected Member Functions inherited from llvm::Value
virtual void	printCustom (raw_ostream &O) const

	Value (Type *Ty, unsigned scid)

unsigned short	getSubclassDataFromValue () const

void	setValueSubclassData (unsigned short D)

Additional Inherited Members
Static Public Attributes inherited from llvm::Value
static const unsigned	MaximumAlignment = 1u << 29

Static Protected Member Functions inherited from llvm::User
template<int Idx, typename U >
static Use &	OpFrom (const U *that)

Protected Attributes inherited from llvm::User
Use *	OperandList

unsigned	NumOperands

Protected Attributes inherited from llvm::Value
unsigned char	SubclassOptionalData: 7

Detailed Description

LLVM Constant Representation.

This is an important base class in LLVM. It provides the common facilities of all constant values in an LLVM program. A constant is a value that is immutable at runtime. Functions are constants because their address is immutable. Same with global variables.

All constants share the capabilities provided in this class. All constants can have a null value. They can have an operand list. Constants can be simple (integer and floating point values), complex (arrays and structures), or expression based (computations yielding a constant value composed of only certain operators and other constant values).

Note that Constants are immutable (once created they never change) and are fully shared by structural equivalence. This means that two structurally equivalent constants will always have the same address. Constants are created on demand as needed and never deleted: thus clients don't have to worry about the lifetime of the objects.

Definition at line 41 of file Constant.h.

Member Enumeration Documentation

enum llvm::Constant::PossibleRelocationsTy

Enumerator
NoRelocation
LocalRelocation
GlobalRelocations

Definition at line 78 of file Constant.h.

Constructor & Destructor Documentation

llvm::Constant::Constant	(	Type *	ty,
		ValueTy	vty,
		Use *	Ops,
		unsigned	NumOps
	)

inlineprotected

Definition at line 47 of file Constant.h.

Member Function Documentation

bool Constant::canTrap ( ) const

canTrap - Return true if evaluation of this constant could trap. This is true for things like constant expressions that could divide by zero.

Definition at line 275 of file Constants.cpp.

References canTrapImpl().

Referenced by SplitCriticalSideEffectEdges().

static bool llvm::Constant::classof ( const Value * V )

inlinestatic

Definition at line 125 of file Constant.h.

References llvm::Value::ConstantFirstVal, llvm::Value::ConstantLastVal, and llvm::Value::getValueID().

virtual void llvm::Constant::destroyConstant ( )

inlinevirtual

destroyConstant - Called if some element of this constant is no longer valid. At this point only other constants may be on the use_list for this constant. Any constants on our Use list must also be destroy'd. The implementation must be sure to remove the constant from the list of available cached constants. Implementations should call destroyConstantImpl as the last thing they do, to destroy all users and delete this.

Reimplemented in llvm::UndefValue, llvm::ConstantExpr, llvm::BlockAddress, llvm::ConstantDataSequential, llvm::ConstantPointerNull, llvm::ConstantVector, llvm::ConstantStruct, llvm::ConstantArray, llvm::ConstantAggregateZero, and llvm::GlobalValue.

Definition at line 122 of file Constant.h.

References llvm_unreachable.

Referenced by destroyConstantImpl(), RemoveDeadConstant(), and llvm::BitcodeReaderValueList::ResolveConstantForwardRefs().

void Constant::destroyConstantImpl ( )

protected

Definition at line 212 of file Constants.cpp.

References llvm::dbgs(), destroyConstant(), llvm::Value::use_back(), and llvm::Value::use_empty().

Referenced by llvm::ConstantAggregateZero::destroyConstant(), llvm::ConstantArray::destroyConstant(), llvm::ConstantStruct::destroyConstant(), llvm::ConstantVector::destroyConstant(), llvm::ConstantPointerNull::destroyConstant(), llvm::ConstantDataSequential::destroyConstant(), llvm::BlockAddress::destroyConstant(), llvm::ConstantExpr::destroyConstant(), and llvm::UndefValue::destroyConstant().

Constant * Constant::getAggregateElement ( unsigned Elt ) const

getAggregateElement - For aggregates (struct/array/vector) return the constant that corresponds to the specified element if possible, or null if not. This can return null if the element index is a ConstantExpr, or if 'this' is a constant expr.

Definition at line 183 of file Constants.cpp.

Referenced by llvm::ConstantFoldCall(), llvm::ConstantFoldExtractElementInstruction(), llvm::ConstantFoldExtractValueInstruction(), llvm::ConstantFoldInsertValueInstruction(), llvm::ConstantFoldLoadThroughGEPConstantExpr(), llvm::ConstantFoldLoadThroughGEPIndices(), EvaluateStoreInto(), FindScalarElement(), FoldBitCast(), llvm::InstCombiner::FoldCmpLoadFromIndexedGlobal(), getAggregateElement(), getArrayElements(), llvm::ShuffleVectorInst::getMaskValue(), llvm::ShuffleVectorInst::getShuffleMask(), getUniqueInteger(), isZero(), ReadDataFromGlobal(), llvm::InstCombiner::visitCallInst(), llvm::InstCombiner::visitExtractValueInst(), llvm::InstCombiner::visitSRem(), and llvm::WriteConstantInternal().

Constant * Constant::getAggregateElement ( Constant * Elt ) const

Definition at line 204 of file Constants.cpp.

References getAggregateElement(), and llvm::Value::getType().

Constant * Constant::getAllOnesValue ( Type * Ty )

static

Get the all ones value.

Returns: the value for an integer or vector of integer constant of the given type that has all its bits set to true.

Definition at line 163 of file Constants.cpp.

References llvm::ConstantInt::get(), llvm::ConstantFP::get(), llvm::APFloat::getAllOnesValue(), llvm::APInt::getAllOnesValue(), llvm::Type::getContext(), llvm::SequentialType::getElementType(), llvm::VectorType::getNumElements(), llvm::Type::getPrimitiveSizeInBits(), llvm::ConstantVector::getSplat(), llvm::Type::isFloatingPointTy(), and llvm::Type::isPPC_FP128Ty().

Referenced by BitCastConstantVector(), llvm::ConstantFoldBinaryInstruction(), llvm::ConstantFoldCompareInstruction(), llvm::BinaryOperator::CreateNot(), DoInitialMatch(), FoldBitCast(), llvm::InstCombiner::FoldICmpAddOpCst(), foldLogOpOfMaskedICmpsHelper(), llvm::X86InstrInfo::foldMemoryOperandImpl(), llvm::ConstantExpr::getBinOpAbsorber(), llvm::ConstantExpr::getBinOpIdentity(), llvm::ScalarEvolution::getNegativeSCEV(), llvm::ConstantExpr::getNot(), llvm::ScalarEvolution::getNotSCEV(), GetSelectFoldableConstant(), getTrue(), LLVMConstAllOnes(), LowerNegateToMultiply(), OptimizeAndOrXor(), SimplifyAddInst(), SimplifyAShrInst(), SimplifyOrInst(), SimplifyXorInst(), ThreadCmpOverSelect(), llvm::InstCombiner::visitICmpInst(), llvm::InstCombiner::visitICmpInstWithCastAndCast(), and llvm::InstCombiner::visitURem().

Constant * Constant::getIntegerValue	(	Type *	Ty,
		const APInt &	V
	)

static

getIntegerValue - Return the value for an integer or pointer constant, or a vector thereof, with the given scalar value.

Definition at line 146 of file Constants.cpp.

References llvm::CallingConv::C, llvm::ConstantInt::get(), llvm::Type::getContext(), llvm::ConstantExpr::getIntToPtr(), llvm::Type::getScalarType(), and llvm::ConstantVector::getSplat().

Constant * Constant::getNullValue ( Type * Ty )

static

Definition at line 111 of file Constants.cpp.

References llvm::lltok::APFloat, llvm::Type::ArrayTyID, llvm::Type::DoubleTyID, llvm::Type::FloatTyID, llvm::Type::FP128TyID, llvm::ConstantInt::get(), llvm::ConstantFP::get(), llvm::ConstantAggregateZero::get(), llvm::ConstantPointerNull::get(), llvm::Type::getContext(), llvm::APInt::getNullValue(), llvm::Type::getTypeID(), llvm::APFloat::getZero(), llvm::Type::HalfTyID, llvm::APFloat::IEEEdouble, llvm::APFloat::IEEEhalf, llvm::APFloat::IEEEquad, llvm::APFloat::IEEEsingle, llvm::Type::IntegerTyID, llvm_unreachable, llvm::Type::PointerTyID, llvm::Type::PPC_FP128TyID, llvm::APFloat::PPCDoubleDouble, llvm::Type::StructTyID, llvm::Type::VectorTyID, llvm::Type::X86_FP80TyID, and llvm::APFloat::x87DoubleExtended.

Constant::PossibleRelocationsTy Constant::getRelocationInfo ( ) const

getRelocationInfo - This method classifies the entry according to whether or not it may generate a relocation entry. This must be conservative, so if it might codegen to a relocatable entry, it should say so. The return values are:

NoRelocation: This constant pool entry is guaranteed to never have a relocation applied to it (because it holds a simple constant like '4'). LocalRelocation: This entry has relocations, but the entries are guaranteed to be resolvable by the static linker, so the dynamic linker will never see them. GlobalRelocations: This entry may have arbitrary relocations.

FIXME: This really should not be in VMCore.

getRelocationInfo - This method classifies the entry according to whether or not it may generate a relocation entry. This must be conservative, so if it might codegen to a relocatable entry, it should say so. The return values are:

NoRelocation: This constant pool entry is guaranteed to never have a relocation applied to it (because it holds a simple constant like '4'). LocalRelocation: This entry has relocations, but the entries are guaranteed to be resolvable by the static linker, so the dynamic linker will never see them. GlobalRelocations: This entry may have arbitrary relocations.

FIXME: This really should not be in IR.

Definition at line 337 of file Constants.cpp.

References llvm::dyn_cast(), llvm::User::getNumOperands(), llvm::ConstantExpr::getOpcode(), llvm::User::getOperand(), GlobalRelocations, LocalRelocation, and NoRelocation.

Referenced by llvm::TargetLoweringObjectFile::getKindForGlobal().

Constant * Constant::getSplatValue ( ) const

getSplatValue - If this is a splat vector constant, meaning that all of the elements have the same value, return that value. Otherwise return 0.

Definition at line 1276 of file Constants.cpp.

References getNullValue(), and llvm::Value::getType().

Referenced by llvm::ComputeMaskedBits(), getUniqueInteger(), llvm::CompositeType::indexValid(), and isAllOnesValue().

const APInt & Constant::getUniqueInteger ( ) const

If C is a constant integer then return its value, otherwise C must be a vector of constant integers, all equal, and the common value is returned.

Definition at line 1301 of file Constants.cpp.

References llvm::CallingConv::C, getAggregateElement(), and getSplatValue().

bool Constant::isAllOnesValue ( ) const

isAllOnesValue - Return true if this is the value that would be returned by getAllOnesValue.

Definition at line 88 of file Constants.cpp.

References getSplatValue().

Referenced by BitCastConstantVector(), ConstantFold(), llvm::ConstantFoldSelectInstruction(), decomposeBitTestICmp(), FoldBitCast(), llvm::InstCombiner::FoldICmpDivCst(), isSelect01(), isSignBitCheck(), and isSignTest().

bool Constant::isConstantUsed ( ) const

isConstantUsed - Return true if the constant has users other than constant exprs and other dangling things.

Definition at line 309 of file Constants.cpp.

References llvm::dyn_cast(), isConstantUsed(), llvm::Value::use_begin(), and llvm::Value::use_end().

Referenced by isConstantUsed().

bool Constant::isNegativeZeroValue ( ) const

isNegativeZeroValue - Return true if the value is what would be returned by getZeroValueForNegation.

Definition at line 45 of file Constants.cpp.

References llvm::Value::getType(), llvm::Type::isFPOrFPVectorTy(), and isNullValue().

Referenced by llvm::InstCombiner::visitFAdd().

bool Constant::isNullValue ( ) const

isNullValue - Return true if this is the value that would be returned by getNullValue.

Definition at line 75 of file Constants.cpp.

Referenced by BitCastConstantVector(), computePointerICmp(), ConstantFold(), llvm::ConstantFoldCastInstruction(), llvm::ConstantFoldCompareInstOperands(), llvm::ConstantFoldCompareInstruction(), llvm::ConstantFoldExtractElementInstruction(), ConstantFoldGetElementPtrImpl(), llvm::ConstantFoldSelectInstruction(), evaluateICmpRelation(), ExtractConstantBytes(), FindScalarElement(), FoldBitCast(), llvm::ConstantArray::get(), llvm::ConstantStruct::get(), llvm::ConstantVector::get(), llvm::getConstantStringInfo(), llvm::LazyValueInfo::getPredicateOnEdge(), isCatchAll(), isNegativeZeroValue(), IsOnlyUsedInZeroEqualityComparison(), isSuitableForBSS(), isZeroValue(), nvptx::LowerConstant(), lowerConstant(), OptimizeOnceStoredGlobal(), ParseGlobalCtors(), passingValueIsAlwaysUndefined(), llvm::ConstantArray::replaceUsesOfWithOnConstant(), llvm::ConstantStruct::replaceUsesOfWithOnConstant(), llvm::ExecutionEngine::runStaticConstructorsDestructors(), TryToShrinkGlobalToBoolean(), TurnSwitchRangeIntoICmp(), llvm::InstCombiner::visitICmpInstWithInstAndIntCst(), and WriteConstants().

bool Constant::isThreadDependent ( ) const

isThreadDependent - Return true if the value can vary between threads.

Definition at line 281 of file Constants.cpp.

References llvm::CallingConv::C, llvm::dyn_cast(), llvm::SmallVectorBase::empty(), llvm::User::getNumOperands(), llvm::User::getOperand(), I, llvm::SmallPtrSet< PtrType, SmallSize >::insert(), llvm::SmallVectorImpl< T >::pop_back_val(), and llvm::SmallVectorTemplateBase< T, isPodLike< T >::value >::push_back().

bool Constant::isZeroValue ( ) const

Return true if the value is negative zero or null value.

Definition at line 66 of file Constants.cpp.

References isNullValue().

Referenced by llvm::ComputeMaskedBits(), and isZero().

void Constant::removeDeadConstantUsers ( ) const

removeDeadConstantUsers - If there are any dead constant users dangling off of this constant, remove them. This method is useful for clients that want to check to see if a global is unused, but don't want to deal with potentially dead constants hanging off of the globals.

Definition at line 395 of file Constants.cpp.

References llvm::dyn_cast(), I, removeDeadUsersOfConstant(), llvm::Value::use_begin(), and llvm::Value::use_end().

Referenced by AddressIsTaken(), hasAddressTakenAndUsed(), INITIALIZE_PASS(), llvm::Inliner::removeDeadFunctions(), and llvm::GlobalValue::~GlobalValue().

virtual void llvm::Constant::replaceUsesOfWithOnConstant	(	Value *	,
		Value *	,
		Use *
	)

inlinevirtual

replaceUsesOfWithOnConstant - This method is a special form of User::replaceUsesOfWith (which does not work on constants) that does work on constants. Basically this method goes through the trouble of building a new constant that is equivalent to the current one, with all uses of From replaced with uses of To. After this construction is completed, all of the users of 'this' are replaced to use the new constant, and then 'this' is deleted. In general, you should not call this method, instead, use Value::replaceAllUsesWith, which automatically dispatches to this method as needed.

Reimplemented in llvm::ConstantExpr, llvm::BlockAddress, llvm::ConstantVector, llvm::ConstantStruct, llvm::ConstantArray, and llvm::GlobalVariable.

Definition at line 140 of file Constant.h.

References llvm::User::getNumOperands(), and llvm_unreachable.

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

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation