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 "InstructionStream.h"
29#include <limits.h>
30#include <wtf/FastBitVector.h>
31#include <wtf/Vector.h>
32
33namespace JSC {
34
35class CodeBlock;
36class UnlinkedCodeBlock;
37struct Instruction;
38
39class BytecodeBasicBlock {
40 WTF_MAKE_FAST_ALLOCATED;
41public:
42 enum SpecialBlockType { EntryBlock, ExitBlock };
43 BytecodeBasicBlock(const InstructionStream::Ref&);
44 BytecodeBasicBlock(SpecialBlockType);
45 void shrinkToFit();
46
47 bool isEntryBlock() { return !m_leaderOffset && !m_totalLength; }
48 bool isExitBlock() { return m_leaderOffset == UINT_MAX && m_totalLength == UINT_MAX; }
49
50 unsigned leaderOffset() const { return m_leaderOffset; }
51 unsigned totalLength() const { return m_totalLength; }
52
53 const Vector<InstructionStream::Offset>& offsets() const { return m_offsets; }
54
55 const Vector<BytecodeBasicBlock*>& successors() const { return m_successors; }
56
57 FastBitVector& in() { return m_in; }
58 FastBitVector& out() { return m_out; }
59
60 unsigned index() const { return m_index; }
61
62 static void compute(CodeBlock*, const InstructionStream& instructions, Vector<std::unique_ptr<BytecodeBasicBlock>>&);
63 static void compute(UnlinkedCodeBlock*, const InstructionStream& instructions, Vector<std::unique_ptr<BytecodeBasicBlock>>&);
64
65private:
66 template<typename Block> static void computeImpl(Block* codeBlock, const InstructionStream& instructions, Vector<std::unique_ptr<BytecodeBasicBlock>>& basicBlocks);
67
68 void addSuccessor(BytecodeBasicBlock* block) { m_successors.append(block); }
69
70 void addLength(unsigned);
71
72 InstructionStream::Offset m_leaderOffset;
73 unsigned m_totalLength;
74 unsigned m_index;
75
76 Vector<InstructionStream::Offset> m_offsets;
77 Vector<BytecodeBasicBlock*> m_successors;
78
79 FastBitVector m_in;
80 FastBitVector m_out;
81};
82
83inline BytecodeBasicBlock::BytecodeBasicBlock(const InstructionStream::Ref& instruction)
84 : m_leaderOffset(instruction.offset())
85 , m_totalLength(instruction->size())
86{
87 m_offsets.append(m_leaderOffset);
88}
89
90inline BytecodeBasicBlock::BytecodeBasicBlock(BytecodeBasicBlock::SpecialBlockType blockType)
91 : m_leaderOffset(blockType == BytecodeBasicBlock::EntryBlock ? 0 : UINT_MAX)
92 , m_totalLength(blockType == BytecodeBasicBlock::EntryBlock ? 0 : UINT_MAX)
93{
94}
95
96inline void BytecodeBasicBlock::addLength(unsigned bytecodeLength)
97{
98 m_offsets.append(m_leaderOffset + m_totalLength);
99 m_totalLength += bytecodeLength;
100}
101
102} // namespace JSC
103