1/*
2 * Copyright (C) 2013, 2015 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "BytecodeBasicBlock.h"
29#include "BytecodeGraph.h"
30#include "CodeBlock.h"
31#include <wtf/FastBitVector.h>
32
33namespace JSC {
34
35class BytecodeKills;
36class FullBytecodeLiveness;
37
38class BytecodeLivenessPropagation {
39protected:
40 template<typename CodeBlockType, typename UseFunctor, typename DefFunctor> void stepOverInstruction(CodeBlockType*, const InstructionStream&, BytecodeGraph&, InstructionStream::Offset bytecodeOffset, const UseFunctor&, const DefFunctor&);
41
42 template<typename CodeBlockType> void stepOverInstruction(CodeBlockType*, const InstructionStream&, BytecodeGraph&, InstructionStream::Offset bytecodeOffset, FastBitVector& out);
43
44 template<typename CodeBlockType, typename Instructions> bool computeLocalLivenessForBytecodeOffset(CodeBlockType*, const Instructions&, BytecodeGraph&, BytecodeBasicBlock*, unsigned targetOffset, FastBitVector& result);
45
46 template<typename CodeBlockType, typename Instructions> bool computeLocalLivenessForBlock(CodeBlockType*, const Instructions&, BytecodeGraph&, BytecodeBasicBlock*);
47
48 template<typename CodeBlockType, typename Instructions> FastBitVector getLivenessInfoAtBytecodeOffset(CodeBlockType*, const Instructions&, BytecodeGraph&, unsigned bytecodeOffset);
49
50 template<typename CodeBlockType, typename Instructions> void runLivenessFixpoint(CodeBlockType*, const Instructions&, BytecodeGraph&);
51};
52
53class BytecodeLivenessAnalysis : private BytecodeLivenessPropagation {
54 WTF_MAKE_FAST_ALLOCATED;
55 WTF_MAKE_NONCOPYABLE(BytecodeLivenessAnalysis);
56public:
57 friend class BytecodeLivenessPropagation;
58 BytecodeLivenessAnalysis(CodeBlock*);
59
60 FastBitVector getLivenessInfoAtBytecodeOffset(CodeBlock*, unsigned bytecodeOffset);
61
62 void computeFullLiveness(CodeBlock*, FullBytecodeLiveness& result);
63 void computeKills(CodeBlock*, BytecodeKills& result);
64
65private:
66 void dumpResults(CodeBlock*);
67
68 void getLivenessInfoAtBytecodeOffset(CodeBlock*, unsigned bytecodeOffset, FastBitVector&);
69
70 BytecodeGraph m_graph;
71};
72
73inline bool operandIsAlwaysLive(int operand);
74inline bool operandThatIsNotAlwaysLiveIsLive(const FastBitVector& out, int operand);
75inline bool operandIsLive(const FastBitVector& out, int operand);
76inline bool isValidRegisterForLiveness(int operand);
77
78} // namespace JSC
79