LLVM  8.0.1
PromoteMemToReg.h
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1 //===- PromoteMemToReg.h - Promote Allocas to Scalars -----------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file exposes an interface to promote alloca instructions to SSA
11 // registers, by using the SSA construction algorithm.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
16 #define LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
17 
18 namespace llvm {
19 
20 template <typename T> class ArrayRef;
21 class AllocaInst;
22 class DominatorTree;
23 class AliasSetTracker;
24 class AssumptionCache;
25 
26 /// Return true if this alloca is legal for promotion.
27 ///
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
31 /// markers.
32 bool isAllocaPromotable(const AllocaInst *AI);
33 
34 /// Promote the specified list of alloca instructions into scalar
35 /// registers, inserting PHI nodes as appropriate.
36 ///
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.
40 ///
41 void PromoteMemToReg(ArrayRef<AllocaInst *> Allocas, DominatorTree &DT,
42  AssumptionCache *AC = nullptr);
43 
44 } // End llvm namespace
45 
46 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:24
bool isAllocaPromotable(const AllocaInst *AI)
Return true if this alloca is legal for promotion.
void PromoteMemToReg(ArrayRef< AllocaInst *> Allocas, DominatorTree &DT, AssumptionCache *AC=nullptr)
Promote the specified list of alloca instructions into scalar registers, inserting PHI nodes as appro...