1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Copyright (C) 2008 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ***** END LICENSE BLOCK ***** */
#ifndef jit_x86_shared_AssemblerBuffer_x86_shared_h
#define jit_x86_shared_AssemblerBuffer_x86_shared_h
#include <stdarg.h>
#include <string.h>
#include "ds/PageProtectingVector.h"
#include "jit/ExecutableAllocator.h"
#include "jit/JitSpewer.h"
// Spew formatting helpers.
#define PRETTYHEX(x) (((x)<0)?"-":""),(((x)<0)?-(x):(x))
#define MEM_o "%s0x%x"
#define MEM_os MEM_o "(,%s,%d)"
#define MEM_ob MEM_o "(%s)"
#define MEM_obs MEM_o "(%s,%s,%d)"
#define MEM_o32 "%s0x%04x"
#define MEM_o32s MEM_o32 "(,%s,%d)"
#define MEM_o32b MEM_o32 "(%s)"
#define MEM_o32bs MEM_o32 "(%s,%s,%d)"
#define MEM_o32r ".Lfrom%d(%%rip)"
#define ADDR_o(offset) PRETTYHEX(offset)
#define ADDR_os(offset, index, scale) ADDR_o(offset), GPRegName((index)), (1<<(scale))
#define ADDR_ob(offset, base) ADDR_o(offset), GPRegName((base))
#define ADDR_obs(offset, base, index, scale) ADDR_ob(offset, base), GPRegName((index)), (1<<(scale))
#define ADDR_o32(offset) ADDR_o(offset)
#define ADDR_o32s(offset, index, scale) ADDR_os(offset, index, scale)
#define ADDR_o32b(offset, base) ADDR_ob(offset, base)
#define ADDR_o32bs(offset, base, index, scale) ADDR_obs(offset, base, index, scale)
#define ADDR_o32r(offset) (offset)
namespace js {
class Sprinter;
namespace jit {
class AssemblerBuffer
{
template<size_t size, typename T>
MOZ_ALWAYS_INLINE void sizedAppendUnchecked(T value)
{
m_buffer.infallibleAppend(reinterpret_cast<unsigned char*>(&value), size);
}
template<size_t size, typename T>
MOZ_ALWAYS_INLINE void sizedAppend(T value)
{
if (MOZ_UNLIKELY(!m_buffer.append(reinterpret_cast<unsigned char*>(&value), size)))
oomDetected();
}
public:
AssemblerBuffer()
: m_oom(false)
{
// Provide memory protection once the buffer starts to get big.
m_buffer.setLowerBoundForProtection(32 * 1024);
}
void ensureSpace(size_t space)
{
if (MOZ_UNLIKELY(m_buffer.length() > (SIZE_MAX - space) ||
!m_buffer.reserve(m_buffer.length() + space)))
oomDetected();
}
bool isAligned(size_t alignment) const
{
return !(m_buffer.length() & (alignment - 1));
}
MOZ_ALWAYS_INLINE void putByteUnchecked(int value) { sizedAppendUnchecked<1>(value); }
MOZ_ALWAYS_INLINE void putShortUnchecked(int value) { sizedAppendUnchecked<2>(value); }
MOZ_ALWAYS_INLINE void putIntUnchecked(int value) { sizedAppendUnchecked<4>(value); }
MOZ_ALWAYS_INLINE void putInt64Unchecked(int64_t value) { sizedAppendUnchecked<8>(value); }
MOZ_ALWAYS_INLINE void putByte(int value) { sizedAppend<1>(value); }
MOZ_ALWAYS_INLINE void putShort(int value) { sizedAppend<2>(value); }
MOZ_ALWAYS_INLINE void putInt(int value) { sizedAppend<4>(value); }
MOZ_ALWAYS_INLINE void putInt64(int64_t value) { sizedAppend<8>(value); }
MOZ_MUST_USE bool append(const unsigned char* values, size_t size)
{
if (MOZ_UNLIKELY(!m_buffer.append(values, size))) {
oomDetected();
return false;
}
return true;
}
unsigned char* data()
{
return m_buffer.begin();
}
size_t size() const
{
return m_buffer.length();
}
bool oom() const
{
return m_oom;
}
const unsigned char* buffer() const {
MOZ_ASSERT(!m_oom);
return m_buffer.begin();
}
void unprotectDataRegion(size_t firstByteOffset, size_t lastByteOffset) {
m_buffer.unprotectRegion(firstByteOffset, lastByteOffset);
}
void reprotectDataRegion(size_t firstByteOffset, size_t lastByteOffset) {
m_buffer.reprotectRegion(firstByteOffset, lastByteOffset);
}
protected:
/*
* OOM handling: This class can OOM in the ensureSpace() method trying
* to allocate a new buffer. In response to an OOM, we need to avoid
* crashing and report the error. We also want to make it so that
* users of this class need to check for OOM only at certain points
* and not after every operation.
*
* Our strategy for handling an OOM is to set m_oom, and then clear (but
* not free) m_buffer, preserving the current buffer. This way, the user
* can continue assembling into the buffer, deferring OOM checking
* until the user wants to read code out of the buffer.
*
* See also the |buffer| method.
*/
void oomDetected() {
m_oom = true;
m_buffer.clear();
}
PageProtectingVector<unsigned char, 256, SystemAllocPolicy> m_buffer;
bool m_oom;
};
class GenericAssembler
{
Sprinter* printer;
public:
GenericAssembler()
: printer(NULL)
{}
void setPrinter(Sprinter* sp) {
printer = sp;
}
void spew(const char* fmt, ...) MOZ_FORMAT_PRINTF(2, 3)
{
if (MOZ_UNLIKELY(printer || JitSpewEnabled(JitSpew_Codegen))) {
va_list va;
va_start(va, fmt);
spew(fmt, va);
va_end(va);
}
}
MOZ_COLD void spew(const char* fmt, va_list va);
};
} // namespace jit
} // namespace js
#endif /* jit_x86_shared_AssemblerBuffer_x86_shared_h */
|
