1/*
2 * Copyright (C) 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#if ENABLE(CONTENT_EXTENSIONS)
29
30#include "DFABytecode.h"
31#include <wtf/Vector.h>
32
33namespace WebCore {
34
35namespace ContentExtensions {
36
37struct DFA;
38class DFANode;
39
40class WEBCORE_EXPORT DFABytecodeCompiler {
41public:
42 DFABytecodeCompiler(const DFA& dfa, Vector<DFABytecode>& bytecode)
43 : m_bytecode(bytecode)
44 , m_dfa(dfa)
45 {
46 }
47
48 void compile();
49
50private:
51 struct Range {
52 Range(uint8_t min, uint8_t max, uint32_t destination, bool caseSensitive)
53 : min(min)
54 , max(max)
55 , destination(destination)
56 , caseSensitive(caseSensitive)
57 {
58 }
59 uint8_t min;
60 uint8_t max;
61 uint32_t destination;
62 bool caseSensitive;
63 };
64 struct JumpTable {
65 ~JumpTable()
66 {
67 ASSERT(min + destinations.size() == static_cast<size_t>(max + 1));
68 ASSERT(min == max || destinations.size() > 1);
69 }
70
71 uint8_t min { 0 };
72 uint8_t max { 0 };
73 bool caseSensitive { true };
74 Vector<uint32_t> destinations;
75 };
76 struct Transitions {
77 Vector<JumpTable> jumpTables;
78 Vector<Range> ranges;
79 bool useFallbackTransition { false };
80 uint32_t fallbackTransitionTarget { std::numeric_limits<uint32_t>::max() };
81 };
82 JumpTable extractJumpTable(Vector<Range>&, unsigned first, unsigned last);
83 Transitions transitions(const DFANode&);
84
85 unsigned compiledNodeMaxBytecodeSize(uint32_t index);
86 void compileNode(uint32_t index, bool root);
87 unsigned nodeTransitionsMaxBytecodeSize(const DFANode&);
88 void compileNodeTransitions(uint32_t nodeIndex);
89 unsigned checkForJumpTableMaxBytecodeSize(const JumpTable&);
90 unsigned checkForRangeMaxBytecodeSize(const Range&);
91 void compileJumpTable(uint32_t nodeIndex, const JumpTable&);
92 void compileCheckForRange(uint32_t nodeIndex, const Range&);
93 int32_t longestPossibleJump(uint32_t jumpLocation, uint32_t sourceNodeIndex, uint32_t destinationNodeIndex);
94
95 void emitAppendAction(uint64_t);
96 void emitJump(uint32_t sourceNodeIndex, uint32_t destinationNodeIndex);
97 void emitCheckValue(uint8_t value, uint32_t sourceNodeIndex, uint32_t destinationNodeIndex, bool caseSensitive);
98 void emitCheckValueRange(uint8_t lowValue, uint8_t highValue, uint32_t sourceNodeIndex, uint32_t destinationNodeIndex, bool caseSensitive);
99 void emitTerminate();
100
101 Vector<DFABytecode>& m_bytecode;
102 const DFA& m_dfa;
103
104 Vector<uint32_t> m_maxNodeStartOffsets;
105 Vector<uint32_t> m_nodeStartOffsets;
106
107 struct LinkRecord {
108 DFABytecodeJumpSize jumpSize;
109 int32_t longestPossibleJump;
110 uint32_t instructionLocation;
111 uint32_t jumpLocation;
112 uint32_t destinationNodeIndex;
113 };
114 Vector<LinkRecord> m_linkRecords;
115};
116
117} // namespace ContentExtensions
118} // namespace WebCore
119
120#endif // ENABLE(CONTENT_EXTENSIONS)
121