llvm-6502/include/llvm/Transforms/Utils/PromoteMemToReg.h
2014-04-25 05:29:35 +00:00

49 lines
1.6 KiB
C++

//===- PromoteMemToReg.h - Promote Allocas to Scalars -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file exposes an interface to promote alloca instructions to SSA
// registers, by using the SSA construction algorithm.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
#define LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
#include "llvm/ADT/ArrayRef.h"
namespace llvm {
class AllocaInst;
class DominatorTree;
class AliasSetTracker;
/// \brief Return true if this alloca is legal for promotion.
///
/// This is true if there are only loads, stores, and lifetime markers
/// (transitively) using this alloca. This also enforces that there is only
/// ever one layer of bitcasts or GEPs between the alloca and the lifetime
/// markers.
bool isAllocaPromotable(const AllocaInst *AI);
/// \brief Promote the specified list of alloca instructions into scalar
/// registers, inserting PHI nodes as appropriate.
///
/// This function makes use of DominanceFrontier information. This function
/// does not modify the CFG of the function at all. All allocas must be from
/// the same function.
///
/// If AST is specified, the specified tracker is updated to reflect changes
/// made to the IR.
void PromoteMemToReg(ArrayRef<AllocaInst *> Allocas, DominatorTree &DT,
AliasSetTracker *AST = nullptr);
} // End llvm namespace
#endif