llvm::PointerUnion< PTs > Class Template Reference

A discriminated union of two or more pointer types, with the discriminator in the low bit of the pointer. More...

#include "llvm/ADT/PointerUnion.h"

Inheritance diagram for llvm::PointerUnion< PTs >:

Public Member Functions
	PointerUnion ()=default
	PointerUnion (std::nullptr_t)
bool	isNull () const
	Test if the pointer held in the union is null, regardless of which type it is.
	operator bool () const
template<typename T >
bool	is () const
	Test if the Union currently holds the type matching T.
template<typename T >
T	get () const
	Returns the value of the specified pointer type.
template<typename T >
T	dyn_cast () const
	Returns the current pointer if it is of the specified pointer type, otherwise returns null.
First const *	getAddrOfPtr1 () const
	If the union is set to the first pointer type get an address pointing to it.
First *	getAddrOfPtr1 ()
	If the union is set to the first pointer type get an address pointing to it.
const PointerUnion &	operator= (std::nullptr_t)
	Assignment from nullptr which just clears the union.
void *	getOpaqueValue () const

Static Public Member Functions
static PointerUnion	getFromOpaqueValue (void *VP)

Friends
template<typename To , typename From , typename Enable >
struct	CastInfo

Detailed Description

template<typename... PTs>
class llvm::PointerUnion< PTs >

A discriminated union of two or more pointer types, with the discriminator in the low bit of the pointer.

This implementation is extremely efficient in space due to leveraging the low bits of the pointer, while exposing a natural and type-safe API.

Common use patterns would be something like this: PointerUnion<int*, float*> P; P = (int*)0; printf("%d %d", P.is<int*>(), P.is<float*>()); // prints "1 0" X = P.get<int*>(); // ok. Y = P.get<float*>(); // runtime assertion failure. Z = P.get<double*>(); // compile time failure. P = (float*)0; Y = P.get<float*>(); // ok. X = P.get<int*>(); // runtime assertion failure. PointerUnion<int*, int*> Q; // compile time failure.

Definition at line 109 of file PointerUnion.h.

Constructor & Destructor Documentation

PointerUnion() [1/2]

template<typename... PTs>

llvm::PointerUnion< PTs >::PointerUnion ( )

default

PointerUnion() [2/2]

template<typename... PTs>

llvm::PointerUnion< PTs >::PointerUnion ( std::nullptr_t  )

inline

Definition at line 136 of file PointerUnion.h.

Member Function Documentation

dyn_cast()

template<typename... PTs>

template<typename T >

T llvm::PointerUnion< PTs >::dyn_cast ( ) const

inline

Returns the current pointer if it is of the specified pointer type, otherwise returns null.

Definition at line 167 of file PointerUnion.h.

get()

template<typename... PTs>

template<typename T >

T llvm::PointerUnion< PTs >::get ( ) const

inline

Returns the value of the specified pointer type.

If the specified pointer type is incorrect, assert.

Definition at line 160 of file PointerUnion.h.

References assert().

getAddrOfPtr1() [1/2]

template<typename... PTs>

First * llvm::PointerUnion< PTs >::getAddrOfPtr1 ( )

inline

If the union is set to the first pointer type get an address pointing to it.

Definition at line 179 of file PointerUnion.h.

References assert().

getAddrOfPtr1() [2/2]

template<typename... PTs>

First const * llvm::PointerUnion< PTs >::getAddrOfPtr1 ( ) const

inline

If the union is set to the first pointer type get an address pointing to it.

Definition at line 173 of file PointerUnion.h.

References llvm::PointerUnion< PTs >::getAddrOfPtr1().

Referenced by llvm::TinyPtrVector< EltTy >::begin(), llvm::PointerUnion< PTs >::getAddrOfPtr1(), and llvm::MachineSDNode::memoperands().

getFromOpaqueValue()

template<typename... PTs>

static PointerUnion llvm::PointerUnion< PTs >::getFromOpaqueValue ( void *  VP )

inlinestatic

Definition at line 199 of file PointerUnion.h.

References llvm::PointerUnion< PTs >::getFromOpaqueValue().

Referenced by llvm::PointerUnion< PTs >::getFromOpaqueValue(), and llvm::PointerLikeTypeTraits< PointerUnion< PTs... > >::getFromVoidPointer().

getOpaqueValue()

template<typename... PTs>

void * llvm::PointerUnion< PTs >::getOpaqueValue ( ) const

inline

Definition at line 198 of file PointerUnion.h.

Referenced by llvm::DenseMapInfo< PointerUnion< PTs... > >::getHashValue(), llvm::DwarfStringPoolEntryRef::operator!=(), llvm::operator!=(), std::hash< VarLocInsertPt >::operator()(), llvm::operator<(), llvm::DwarfStringPoolEntryRef::operator==(), and llvm::operator==().

is()

template<typename... PTs>

template<typename T >

bool llvm::PointerUnion< PTs >::is ( ) const

inline

Test if the Union currently holds the type matching T.

Definition at line 151 of file PointerUnion.h.

isNull()

template<typename... PTs>

bool llvm::PointerUnion< PTs >::isNull ( ) const

inline

Test if the pointer held in the union is null, regardless of which type it is.

Definition at line 141 of file PointerUnion.h.

Referenced by llvm::TinyPtrVector< EltTy >::empty(), llvm::TinyPtrVector< EltTy >::end(), llvm::ReplaceableMetadataImpl::getAllArgListUsers(), llvm::ReplaceableMetadataImpl::getAllDbgVariableRecordUsers(), llvm::SelectionDAG::getLoad(), llvm::SelectionDAG::getLoadVP(), llvm::MachineFunction::getMachineMemOperand(), llvm::SelectionDAG::getStore(), llvm::SelectionDAG::getTruncStore(), llvm::SelectionDAG::getTruncStoreVP(), llvm::MachinePointerInfo::getWithOffset(), llvm::TinyPtrVector< EltTy >::insert(), llvm::MachineMemOperand::MachineMemOperand(), llvm::PointerUnion< PTs >::operator bool(), llvm::DwarfStringPoolEntryRef::operator bool(), llvm::TinyPtrVector< EltTy >::operator[](), llvm::TinyPtrVector< EltTy >::push_back(), and llvm::TinyPtrVector< EltTy >::size().

operator bool()

template<typename... PTs>

llvm::PointerUnion< PTs >::operator bool ( ) const

inlineexplicit

Definition at line 143 of file PointerUnion.h.

References llvm::PointerUnion< PTs >::isNull().

operator=()

template<typename... PTs>

const PointerUnion & llvm::PointerUnion< PTs >::operator= ( std::nullptr_t  )

inline

Assignment from nullptr which just clears the union.

Definition at line 190 of file PointerUnion.h.

Friends And Related Function Documentation

CastInfo

template<typename... PTs>

template<typename To , typename From , typename Enable >

friend struct CastInfo

friend

Definition at line 131 of file PointerUnion.h.

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

• include/llvm/ADT/PointerUnion.h