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

#include "llvm/ADT/PointerUnion.h"

Inheritance diagram for llvm::PointerUnion< PTs >:

Public Member Functions
	PointerUnion ()=default
	PointerUnion (std::nullptr_t)
const PointerUnion &	operator= (std::nullptr_t)
	Assignment from nullptr clears the union, resetting to the first type.
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.
void *	getOpaqueValue () const

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

Friends
template<typename, int, typename...>
class	pointer_union_detail::PointerUnionMembers
template<typename To, typename From, typename Enable>
struct	CastInfo
template<typename>
struct	PointerLikeTypeTraits
bool	operator== (PointerUnion lhs, PointerUnion rhs)
bool	operator!= (PointerUnion lhs, PointerUnion rhs)
bool	operator< (PointerUnion lhs, PointerUnion rhs)

Detailed Description

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

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

When all types have enough alignment for a fixed-width tag, the tag is placed in the high end of the available low bits, leaving spare low bits for nesting in PointerIntPair or SmallPtrSet. When types have heterogeneous alignment, a variable-length escape-encoded tag is used; in that case, types must be listed in non-decreasing NumLowBitsAvailable order.

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 190 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 274 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 316 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 309 of file PointerUnion.h.

◆ 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 328 of file PointerUnion.h.

◆ 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 322 of file PointerUnion.h.

Referenced by llvm::PointerUnion< TrivialCallback *, NonTrivialCallbacks * >::getAddrOfPtr1().

◆ getFromOpaqueValue()

template<typename... PTs>

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

inlinestatic

Definition at line 345 of file PointerUnion.h.

◆ getOpaqueValue()

template<typename... PTs>

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

inline

Definition at line 341 of file PointerUnion.h.

Referenced by llvm::DenseMapInfo< PointerUnion< PTs... > >::getHashValue(), llvm::PointerUnion< TrivialCallback *, NonTrivialCallbacks * >::operator!=, std::hash< VarLocInsertPt >::operator()(), llvm::PointerUnion< TrivialCallback *, NonTrivialCallbacks * >::operator<, and llvm::PointerUnion< TrivialCallback *, NonTrivialCallbacks * >::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 302 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 286 of file PointerUnion.h.

Referenced by llvm::SelectionDAG::getLoad(), llvm::SelectionDAG::getLoadVP(), llvm::MachineFunction::getMachineMemOperand(), llvm::SelectionDAG::getStore(), llvm::SelectionDAG::getTruncStore(), llvm::SelectionDAG::getTruncStoreVP(), and llvm::PointerUnion< TrivialCallback *, NonTrivialCallbacks * >::operator bool().

◆ operator bool()

template<typename... PTs>

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

inlineexplicit

Definition at line 296 of file PointerUnion.h.

◆ operator=()

template<typename... PTs>

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

inline

Assignment from nullptr clears the union, resetting to the first type.

Definition at line 279 of file PointerUnion.h.

◆ CastInfo

template<typename... PTs>

template<typename To, typename From, typename Enable>

friend struct CastInfo

friend

Definition at line 202 of file PointerUnion.h.

◆ operator!=

template<typename... PTs>

bool operator!=	(	PointerUnion< PTs >	lhs,
		PointerUnion< PTs >	rhs )

friend

Definition at line 355 of file PointerUnion.h.

◆ operator<

template<typename... PTs>

bool operator<	(	PointerUnion< PTs >	lhs,
		PointerUnion< PTs >	rhs )

friend

Definition at line 359 of file PointerUnion.h.

◆ operator==

template<typename... PTs>

bool operator==	(	PointerUnion< PTs >	lhs,
		PointerUnion< PTs >	rhs )

friend

Definition at line 351 of file PointerUnion.h.

◆ pointer_union_detail::PointerUnionMembers

template<typename... PTs>

template<typename, int, typename...>

friend class pointer_union_detail::PointerUnionMembers

friend

Definition at line 201 of file PointerUnion.h.

◆ PointerLikeTypeTraits

template<typename... PTs>

template<typename>

friend struct PointerLikeTypeTraits

friend

Definition at line 203 of file PointerUnion.h.

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

include/llvm/ADT/PointerUnion.h

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

◆ PointerUnion() [1/2]

◆ PointerUnion() [2/2]

Member Function Documentation

◆ dyn_cast()

◆ get()

◆ getAddrOfPtr1() [1/2]

◆ getAddrOfPtr1() [2/2]

◆ getFromOpaqueValue()

◆ getOpaqueValue()

◆ is()

◆ isNull()

◆ operator bool()

◆ operator=()

Friends And Related Symbol Documentation

◆ CastInfo

◆ operator!=

◆ operator<

◆ operator==

◆ pointer_union_detail::PointerUnionMembers

◆ PointerLikeTypeTraits