1//===- Transform/Utils/CodeMoverUtils.h - CodeMover Utils -------*- 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 family of functions determine movements are safe on basic blocks, and
10// instructions contained within a function.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_TRANSFORMS_UTILS_CODEMOVERUTILS_H
15#define LLVM_TRANSFORMS_UTILS_CODEMOVERUTILS_H
16
17namespace llvm {
18
19class BasicBlock;
20class DependenceInfo;
21class DominatorTree;
22class Instruction;
23class PostDominatorTree;
24
25/// Return true if \p I0 and \p I1 are control flow equivalent.
26/// Two instructions are control flow equivalent if their basic blocks are
27/// control flow equivalent.
28bool isControlFlowEquivalent(const Instruction &I0, const Instruction &I1,
29 const DominatorTree &DT,
30 const PostDominatorTree &PDT);
31
32/// Return true if \p BB0 and \p BB1 are control flow equivalent.
33/// Two basic blocks are control flow equivalent if when one executes, the other
34/// is guaranteed to execute.
35bool isControlFlowEquivalent(const BasicBlock &BB0, const BasicBlock &BB1,
36 const DominatorTree &DT,
37 const PostDominatorTree &PDT);
38
39/// Return true if \p I can be safely moved before \p InsertPoint.
40bool isSafeToMoveBefore(Instruction &I, Instruction &InsertPoint,
41 DominatorTree &DT,
42 const PostDominatorTree *PDT = nullptr,
43 DependenceInfo *DI = nullptr);
44
45/// Return true if all instructions (except the terminator) in \p BB can be
46/// safely moved before \p InsertPoint.
47bool isSafeToMoveBefore(BasicBlock &BB, Instruction &InsertPoint,
48 DominatorTree &DT,
49 const PostDominatorTree *PDT = nullptr,
50 DependenceInfo *DI = nullptr);
51
52/// Move instructions, in an order-preserving manner, from \p FromBB to the
53/// beginning of \p ToBB when proven safe.
54void moveInstructionsToTheBeginning(BasicBlock &FromBB, BasicBlock &ToBB,
55 DominatorTree &DT,
56 const PostDominatorTree &PDT,
57 DependenceInfo &DI);
58
59/// Move instructions, in an order-preserving manner, from \p FromBB to the end
60/// of \p ToBB when proven safe.
61void moveInstructionsToTheEnd(BasicBlock &FromBB, BasicBlock &ToBB,
62 DominatorTree &DT, const PostDominatorTree &PDT,
63 DependenceInfo &DI);
64
65} // end namespace llvm
66
67#endif // LLVM_TRANSFORMS_UTILS_CODEMOVERUTILS_H
68