mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-11-03 14:21:30 +00:00
d0fde30ce8
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9903 91177308-0d34-0410-b5e6-96231b3b80d8
35 lines
1.3 KiB
C++
35 lines
1.3 KiB
C++
//===- DemoteRegToStack.h - Move a virtual reg. to stack --------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file was developed by the LLVM research group and is distributed under
|
|
// the University of Illinois Open Source License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace llvm {
|
|
|
|
class Instruction;
|
|
class AllocaInst;
|
|
|
|
AllocaInst *DemoteRegToStack(Instruction &X);
|
|
|
|
} // End llvm namespace
|