llvm-6502/include/llvm/Transforms/Utils/DemoteRegToStack.h
Vikram S. Adve 1690f1d77d This file provides the function DemoteRegToStack(), which takes a
virtual register computed by an Instruction& X and replaces it with
a slot in the stack frame, allocated via alloca.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4963 91177308-0d34-0410-b5e6-96231b3b80d8
2002-12-10 13:07:12 +00:00

22 lines
960 B
C++

//===- DemoteRegToStack.h - Move a virtual reg. to stack --------*- C++ -*-===//
// This file provides the function:
// AllocaInst* DemoteRegToStack(Instruction& X):
//
// This function takes a virtual register computed by an
// Instruction& X and replaces it with a slot in the stack frame,
// allocated via alloca. It has to:
// (1) Identify all Phi operations that have X as an operand and
// transitively other Phis that use such Phis;
// (2) Store all values merged with X via Phi operations to the stack slot;
// (3) Load the value from the stack slot just before any use of X or any
// of the Phis that were eliminated; and
// (4) Delete X and all the Phis, which should all now be dead.
//
// Returns the pointer to the alloca inserted to create a stack slot for X.
//----------------------------------------------------------------------------
class Instruction;
class AllocaInst;
extern AllocaInst* DemoteRegToStack(Instruction& X);