Placeholder metadata for operands of distinct MDNodes. More...

#include "llvm/IR/Metadata.h"

Inheritance diagram for llvm::DistinctMDOperandPlaceholder:

Public Member Functions
	DistinctMDOperandPlaceholder (unsigned ID)
	DistinctMDOperandPlaceholder ()=delete
	DistinctMDOperandPlaceholder (DistinctMDOperandPlaceholder &&)=delete
	DistinctMDOperandPlaceholder (const DistinctMDOperandPlaceholder &)=delete
	~DistinctMDOperandPlaceholder ()
unsigned	getID () const
void	replaceUseWith (Metadata *MD)
	Replace the use of this with MD.
Public Member Functions inherited from llvm::Metadata
unsigned	getMetadataID () const
LLVM_ABI void	dump () const
	User-friendly dump.
LLVM_ABI void	dump (const Module *M) const
LLVM_ABI void	print (raw_ostream &OS, const Module *M=nullptr, bool IsForDebug=false) const
	Print.
LLVM_ABI void	print (raw_ostream &OS, ModuleSlotTracker &MST, const Module *M=nullptr, bool IsForDebug=false) const
LLVM_ABI void	printAsOperand (raw_ostream &OS, const Module *M=nullptr) const
	Print as operand.
LLVM_ABI void	printAsOperand (raw_ostream &OS, ModuleSlotTracker &MST, const Module *M=nullptr) const

Friends
class	MetadataTracking

Additional Inherited Members
Public Types inherited from llvm::Metadata
enum	MetadataKind
Static Public Attributes inherited from llvm::Metadata
static constexpr const unsigned	PoisonGeneratingIDs []
	Metadata IDs that may generate poison.
Protected Types inherited from llvm::Metadata
enum	StorageType { Uniqued , Distinct , Temporary }
	Active type of storage. More...
Protected Member Functions inherited from llvm::Metadata
	Metadata (unsigned ID, StorageType Storage)
	~Metadata ()=default
void	handleChangedOperand (void , Metadata )
	Default handling of a changed operand, which asserts.
Protected Attributes inherited from llvm::Metadata
unsigned char	Storage: 7
	Storage flag for non-uniqued, otherwise unowned, metadata.
unsigned char	SubclassData1: 1
unsigned short	SubclassData16 = 0
unsigned	SubclassData32 = 0

Detailed Description

Placeholder metadata for operands of distinct MDNodes.

This is a lightweight placeholder for an operand of a distinct node. It's purpose is to help track forward references when creating a distinct node. This allows distinct nodes involved in a cycle to be constructed before their operands without requiring a heavyweight temporary node with full-blown RAUW support.

Each placeholder supports only a single MDNode user. Clients should pass an ID, retrieved via getID(), to indicate the "real" operand that this should be replaced with.

While it would be possible to implement move operators, they would be fairly expensive. Leave them unimplemented to discourage their use (clients can use std::deque, std::list, BumpPtrAllocator, etc.).

Definition at line 1704 of file Metadata.h.