1 | /* |
2 | * Copyright (C) 2008, 2012 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. ``AS IS'' AND ANY |
14 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
15 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
17 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
18 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
19 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
20 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
21 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
23 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #ifndef AssemblerBuffer_h |
27 | #define AssemblerBuffer_h |
28 | |
29 | #if ENABLE(ASSEMBLER) |
30 | |
31 | #include "ExecutableAllocator.h" |
32 | #include "JITCompilationEffort.h" |
33 | #include "JSGlobalData.h" |
34 | #include "stdint.h" |
35 | #include <string.h> |
36 | #include <wtf/Assertions.h> |
37 | #include <wtf/FastMalloc.h> |
38 | #include <wtf/StdLibExtras.h> |
39 | |
40 | namespace JSC { |
41 | |
42 | struct AssemblerLabel { |
43 | AssemblerLabel() |
44 | : m_offset(std::numeric_limits<uint32_t>::max()) |
45 | { |
46 | } |
47 | |
48 | explicit AssemblerLabel(uint32_t offset) |
49 | : m_offset(offset) |
50 | { |
51 | } |
52 | |
53 | bool isSet() const { return (m_offset != std::numeric_limits<uint32_t>::max()); } |
54 | |
55 | AssemblerLabel labelAtOffset(int offset) const |
56 | { |
57 | return AssemblerLabel(m_offset + offset); |
58 | } |
59 | |
60 | uint32_t m_offset; |
61 | }; |
62 | |
63 | class AssemblerBuffer { |
64 | static const int inlineCapacity = 128; |
65 | public: |
66 | AssemblerBuffer() |
67 | : m_storage(inlineCapacity) |
68 | , m_buffer(&(*m_storage.begin())) |
69 | , m_capacity(inlineCapacity) |
70 | , m_index(0) |
71 | { |
72 | } |
73 | |
74 | ~AssemblerBuffer() |
75 | { |
76 | } |
77 | |
78 | bool isAvailable(int space) |
79 | { |
80 | return m_index + space <= m_capacity; |
81 | } |
82 | |
83 | void ensureSpace(int space) |
84 | { |
85 | if (!isAvailable(space)) |
86 | grow(); |
87 | } |
88 | |
89 | bool isAligned(int alignment) const |
90 | { |
91 | return !(m_index & (alignment - 1)); |
92 | } |
93 | |
94 | template<typename IntegralType> |
95 | void putIntegral(IntegralType value) |
96 | { |
97 | ensureSpace(space: sizeof(IntegralType)); |
98 | putIntegralUnchecked(value); |
99 | } |
100 | |
101 | template<typename IntegralType> |
102 | void putIntegralUnchecked(IntegralType value) |
103 | { |
104 | ASSERT(isAvailable(sizeof(IntegralType))); |
105 | memcpy(m_buffer + m_index, &value, sizeof(IntegralType)); |
106 | m_index += sizeof(IntegralType); |
107 | } |
108 | |
109 | void putByteUnchecked(int8_t value) { putIntegralUnchecked(value); } |
110 | void putByte(int8_t value) { putIntegral(value); } |
111 | void putShortUnchecked(int16_t value) { putIntegralUnchecked(value); } |
112 | void putShort(int16_t value) { putIntegral(value); } |
113 | void putIntUnchecked(int32_t value) { putIntegralUnchecked(value); } |
114 | void putInt(int32_t value) { putIntegral(value); } |
115 | void putInt64Unchecked(int64_t value) { putIntegralUnchecked(value); } |
116 | void putInt64(int64_t value) { putIntegral(value); } |
117 | |
118 | void* data() const |
119 | { |
120 | return m_buffer; |
121 | } |
122 | |
123 | size_t codeSize() const |
124 | { |
125 | return m_index; |
126 | } |
127 | |
128 | AssemblerLabel label() const |
129 | { |
130 | return AssemblerLabel(m_index); |
131 | } |
132 | |
133 | PassRefPtr<ExecutableMemoryHandle> executableCopy(JSGlobalData& globalData, void* ownerUID, JITCompilationEffort effort) |
134 | { |
135 | if (!m_index) |
136 | return 0; |
137 | |
138 | RefPtr<ExecutableMemoryHandle> result = globalData.executableAllocator.allocate(globalData, size: m_index, ownerUID, effort); |
139 | |
140 | if (!result) |
141 | return 0; |
142 | |
143 | if (Q_UNLIKELY(!ExecutableAllocator::makeWritable(result->memoryStart(), result->memorySize()))) |
144 | return 0; |
145 | |
146 | memcpy(dest: result->codeStart(), src: m_buffer, n: m_index); |
147 | |
148 | return result.release(); |
149 | } |
150 | |
151 | unsigned debugOffset() { return m_index; } |
152 | |
153 | protected: |
154 | void append(const char* data, int size) |
155 | { |
156 | if (!isAvailable(space: size)) |
157 | grow(extraCapacity: size); |
158 | |
159 | memcpy(dest: m_buffer + m_index, src: data, n: size); |
160 | m_index += size; |
161 | } |
162 | |
163 | void grow(int = 0) |
164 | { |
165 | m_capacity += m_capacity / 2 + extraCapacity; |
166 | |
167 | m_storage.grow(size: m_capacity); |
168 | m_buffer = &(*m_storage.begin()); |
169 | } |
170 | |
171 | private: |
172 | Vector<char, inlineCapacity, UnsafeVectorOverflow> m_storage; |
173 | char* m_buffer; |
174 | int m_capacity; |
175 | int m_index; |
176 | }; |
177 | |
178 | } // namespace JSC |
179 | |
180 | #endif // ENABLE(ASSEMBLER) |
181 | |
182 | #endif // AssemblerBuffer_h |
183 | |