1 //===- PromoteMemToReg.h - Promote Allocas to Scalars -----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file exposes an interface to promote alloca instructions to SSA
11 // registers, by using the SSA construction algorithm.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
16 #define LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
18 #include "llvm/ADT/ArrayRef.h"
24 class AliasSetTracker;
26 /// \brief Return true if this alloca is legal for promotion.
28 /// This is true if there are only loads, stores, and lifetime markers
29 /// (transitively) using this alloca. This also enforces that there is only
30 /// ever one layer of bitcasts or GEPs between the alloca and the lifetime
32 bool isAllocaPromotable(const AllocaInst *AI);
34 /// \brief Promote the specified list of alloca instructions into scalar
35 /// registers, inserting PHI nodes as appropriate.
37 /// This function makes use of DominanceFrontier information. This function
38 /// does not modify the CFG of the function at all. All allocas must be from
39 /// the same function.
41 /// If AST is specified, the specified tracker is updated to reflect changes
43 void PromoteMemToReg(ArrayRef<AllocaInst *> Allocas, DominatorTree &DT,
44 AliasSetTracker *AST = nullptr);
46 } // End llvm namespace