1/*
2 * Copyright (C) 2008 Apple Inc. All rights reserved.
3 * Copyright (C) 2008 Cameron Zwarich <[email protected]>
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
15 * its contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
19 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
22 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#ifndef JumpTable_h
31#define JumpTable_h
32
33#include "MacroAssembler.h"
34#include "UString.h"
35#include <wtf/HashMap.h>
36#include <wtf/Vector.h>
37
38namespace JSC {
39
40 struct OffsetLocation {
41 int32_t branchOffset;
42#if ENABLE(JIT)
43 CodeLocationLabel ctiOffset;
44#endif
45 };
46
47 struct StringJumpTable {
48 typedef HashMap<RefPtr<UString::Rep>, OffsetLocation> StringOffsetTable;
49 StringOffsetTable offsetTable;
50#if ENABLE(JIT)
51 CodeLocationLabel ctiDefault; // FIXME: it should not be necessary to store this.
52#endif
53
54 inline int32_t offsetForValue(UString::Rep* value, int32_t defaultOffset)
55 {
56 StringOffsetTable::const_iterator end = offsetTable.end();
57 StringOffsetTable::const_iterator loc = offsetTable.find(key: value);
58 if (loc == end)
59 return defaultOffset;
60 return loc->second.branchOffset;
61 }
62
63#if ENABLE(JIT)
64 inline CodeLocationLabel ctiForValue(UString::Rep* value)
65 {
66 StringOffsetTable::const_iterator end = offsetTable.end();
67 StringOffsetTable::const_iterator loc = offsetTable.find(key: value);
68 if (loc == end)
69 return ctiDefault;
70 return loc->second.ctiOffset;
71 }
72#endif
73 };
74
75 struct SimpleJumpTable {
76 // FIXME: The two Vectors can be combind into one Vector<OffsetLocation>
77 Vector<int32_t> branchOffsets;
78 int32_t min;
79#if ENABLE(JIT)
80 Vector<CodeLocationLabel> ctiOffsets;
81 CodeLocationLabel ctiDefault;
82#endif
83
84 int32_t offsetForValue(int32_t value, int32_t defaultOffset);
85 void add(int32_t key, int32_t offset)
86 {
87 if (!branchOffsets[key])
88 branchOffsets[key] = offset;
89 }
90
91#if ENABLE(JIT)
92 inline CodeLocationLabel ctiForValue(int32_t value)
93 {
94 if (value >= min && static_cast<uint32_t>(value - min) < ctiOffsets.size())
95 return ctiOffsets[value - min];
96 return ctiDefault;
97 }
98#endif
99 };
100
101} // namespace JSC
102
103#endif // JumpTable_h
104

source code of qtscript/src/3rdparty/javascriptcore/JavaScriptCore/bytecode/JumpTable.h