Use.h File Reference

#include "llvm-c/Core.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/Support/CBindingWrapping.h"
#include "llvm/Support/Compiler.h"
#include <cstddef>
#include <iterator>

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Classes
class	llvm::PointerLikeTypeTraits< Use ** >
class	llvm::Use
	A Use represents the edge between a Value definition and its users. More...
struct	llvm::simplify_type< Use >
	Allow clients to treat uses just like values when using casting operators. More...
struct	llvm::simplify_type< const Use >
Namespaces
namespace	llvm
	List of target independent CodeGen pass IDs.

---

Detailed Description

This defines the Use class. The Use class represents the operand of an instruction or some other User instance which refers to a Value. The Use class keeps the "use list" of the referenced value up to date.

Pointer tagging is used to efficiently find the User corresponding to a Use without having to store a User pointer in every Use. A User is preceded in memory by all the Uses corresponding to its operands, and the low bits of one of the fields (Prev) of the Use class are used to encode offsets to be able to find that User given a pointer to any Use. For details, see:

http://www.llvm.org/docs/ProgrammersManual.html#UserLayout

Definition in file Use.h.