llvm::UndefValue Class Reference

#include <Constants.h>

Inheritance diagram for llvm::UndefValue:

Collaboration diagram for llvm::UndefValue:

List of all members.

Public Member Functions
UndefValue *	getSequentialElement () const
UndefValue *	getStructElement (unsigned Elt) const
UndefValue *	getElementValue (Constant *C) const
UndefValue *	getElementValue (unsigned Idx) const
virtual void	destroyConstant ()
Static Public Member Functions
static UndefValue *	get (Type *T)
static bool	classof (const Value *V)
	Methods for support type inquiry through isa, cast, and dyn_cast:
Protected Member Functions
	UndefValue (Type *T)
void *	operator new (size_t s)

---

Detailed Description

UndefValue - 'undef' values are things that do not have specified contents. These are used for a variety of purposes, including global variable initializers and operands to instructions. 'undef' values can occur with any first-class type.

Undef values aren't exactly constants; if they have multiple uses, they can appear to have different bit patterns at each use. See LangRef.html::undefvalues for details.

Definition at line 1122 of file Constants.h.

---

Constructor & Destructor Documentation

llvm::UndefValue::UndefValue

(

Type *

T

)

[inline, explicit, protected]

Definition at line 1126 of file Constants.h.

---

Member Function Documentation

static bool llvm::UndefValue::classof

(

const Value *

V

)

[inline, static]

Methods for support type inquiry through isa, cast, and dyn_cast:

Reimplemented from llvm::Constant.

Definition at line 1157 of file Constants.h.

References llvm::Value::getValueID().

void UndefValue::destroyConstant

(

)

[virtual]

destroyConstant - Called if some element of this constant is no longer valid.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 from llvm::Constant.

Definition at line 1345 of file Constants.cpp.

References llvm::Constant::destroyConstantImpl(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT >::erase(), llvm::Value::getContext(), llvm::Value::getType(), llvm::LLVMContext::pImpl, and llvm::LLVMContextImpl::UVConstants.

UndefValue * UndefValue::get

(

Type *

T

)

[static]

get() - Static factory methods - Return an 'undef' object of the specified type.

Definition at line 1335 of file Constants.cpp.

References llvm::Type::getContext(), llvm::LLVMContext::pImpl, and llvm::LLVMContextImpl::UVConstants.

Referenced by BuildSubAggregate(), changeToUnreachable(), llvm::CloneAndPruneFunctionInto(), CollectShuffleElements(), CollectSingleShuffleElements(), llvm::ConstantFoldBinaryInstruction(), llvm::ConstantFoldCall(), llvm::ConstantFoldCastInstruction(), llvm::ConstantFoldCompareInstruction(), llvm::ConstantFoldExtractElementInstruction(), ConstantFoldGetElementPtrImpl(), llvm::ConstantFoldInstruction(), llvm::ConstantFoldLoadFromConstPtr(), llvm::ConstantFoldShuffleVectorInstruction(), ConvertShiftToMul(), llvm::IRBuilder< true, TargetFolder >::CreateAggregateRet(), llvm::IRBuilder< true, TargetFolder >::CreateVectorSplat(), llvm::DeleteDeadBlock(), DeleteInstructionInBlock(), llvm::InstCombiner::DoOneIteration(), extractVector(), FindScalarElement(), FoldReinterpretLoadFromConstPtr(), llvm::FoldSingleEntryPHINodes(), getSequentialElement(), getStructElement(), llvm::SSAUpdaterTraits< SSAUpdater >::GetUndefVal(), llvm::SSAUpdater::GetValueInMiddleOfBlock(), llvm::PHINode::hasConstantValue(), llvm::InlineFunction(), insertVector(), LinearizeExprTree(), LLVMGetUndef(), llvm::R600TargetLowering::LowerFormalArguments(), llvm::IntrinsicLowering::LowerIntrinsicCall(), llvm::MapValue(), llvm::MergeBasicBlockIntoOnlyPred(), OptimizeGlobalAddressOfMalloc(), OptimizeVectorResize(), llvm::RecursivelyDeleteDeadPHINode(), llvm::PHINode::removeIncomingValue(), llvm::BasicBlock::removePredecessor(), llvm::InstCombiner::ReplaceInstUsesWith(), llvm::LoadAndStorePromoter::run(), SimplifyCall(), SimplifyFCmpInst(), SimplifyGEPInst(), llvm::SimplifyInstruction(), SimplifyPHINode(), SimplifyRem(), SimplifyShift(), SimplifySubInst(), llvm::InstCombiner::SliceUpIllegalIntegerPHI(), llvm::SplitBlockPredecessors(), llvm::InstCombiner::visitAllocSite(), llvm::InstCombiner::visitBitCast(), llvm::InstCombiner::visitCallInst(), llvm::InstCombiner::visitExtractElementInst(), llvm::InstCombiner::visitExtractValueInst(), llvm::InstCombiner::visitFPTrunc(), llvm::InstCombiner::visitFree(), llvm::InstCombiner::visitInsertElementInst(), llvm::InstCombiner::visitLoadInst(), llvm::InstCombiner::visitPHINode(), llvm::ObjectSizeOffsetEvaluator::visitPHINode(), llvm::InstCombiner::visitShuffleVectorInst(), and llvm::InstCombiner::visitStoreInst().

UndefValue * UndefValue::getElementValue

(

Constant *

C

)

const

getElementValue - Return an undef of the right value for the specified GEP index.

getElementValue - Return an undef of the right value for the specified GEP index if we can, otherwise return null (e.g. if C is a ConstantExpr).

Definition at line 707 of file Constants.cpp.

References getSequentialElement(), getStructElement(), and llvm::Value::getType().

UndefValue * UndefValue::getElementValue

(

unsigned

Idx

)

const

getElementValue - Return an undef of the right value for the specified GEP index.

Definition at line 715 of file Constants.cpp.

References getSequentialElement(), getStructElement(), and llvm::Value::getType().

UndefValue * UndefValue::getSequentialElement

(

)

const

getSequentialElement - If this Undef has array or vector type, return a undef with the right element type.

getSequentialElement - If this undef has array or vector type, return an undef with the right element type.

Definition at line 695 of file Constants.cpp.

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

Referenced by getElementValue().

UndefValue * UndefValue::getStructElement

(

unsigned

Elt

)

const

getStructElement - If this undef has struct type, return a undef with the right element type for the specified element.

getStructElement - If this undef has struct type, return a zero with the right element type for the specified element.

Definition at line 701 of file Constants.cpp.

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

Referenced by getElementValue().

void* llvm::UndefValue::operator new

(

size_t

s

)

[inline, protected]

Reimplemented from llvm::User.

Definition at line 1129 of file Constants.h.

---

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

• Constants.h
• Constants.cpp