LLVM  11.0.0git
PromoteMemToReg.h
Go to the documentation of this file.
1 //===- PromoteMemToReg.h - Promote Allocas to Scalars -----------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file exposes an interface to promote alloca instructions to SSA
10 // registers, by using the SSA construction algorithm.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
15 #define LLVM_TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
16 
17 namespace llvm {
18 
19 template <typename T> class ArrayRef;
20 class AllocaInst;
21 class DominatorTree;
22 class AssumptionCache;
23 
24 /// Return true if this alloca is legal for promotion.
25 ///
26 /// This is true if there are only loads, stores, and lifetime markers
27 /// (transitively) using this alloca. This also enforces that there is only
28 /// ever one layer of bitcasts or GEPs between the alloca and the lifetime
29 /// markers.
30 bool isAllocaPromotable(const AllocaInst *AI);
31 
32 /// Promote the specified list of alloca instructions into scalar
33 /// registers, inserting PHI nodes as appropriate.
34 ///
35 /// This function makes use of DominanceFrontier information. This function
36 /// does not modify the CFG of the function at all. All allocas must be from
37 /// the same function.
38 ///
39 void PromoteMemToReg(ArrayRef<AllocaInst *> Allocas, DominatorTree &DT,
40  AssumptionCache *AC = nullptr);
41 
42 } // End llvm namespace
43 
44 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:23
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...