1 | /* |
2 | * Copyright (C) 2009 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 RepatchBuffer_h |
27 | #define RepatchBuffer_h |
28 | |
29 | #include <wtf/Platform.h> |
30 | |
31 | #if ENABLE(ASSEMBLER) |
32 | |
33 | #include <MacroAssembler.h> |
34 | #include <wtf/Noncopyable.h> |
35 | |
36 | namespace JSC { |
37 | |
38 | // RepatchBuffer: |
39 | // |
40 | // This class is used to modify code after code generation has been completed, |
41 | // and after the code has potentially already been executed. This mechanism is |
42 | // used to apply optimizations to the code. |
43 | // |
44 | class RepatchBuffer { |
45 | typedef MacroAssemblerCodePtr CodePtr; |
46 | |
47 | public: |
48 | RepatchBuffer(CodeBlock* codeBlock) |
49 | { |
50 | JITCode& code = codeBlock->getJITCode(); |
51 | m_start = code.start(); |
52 | m_size = code.size(); |
53 | |
54 | ExecutableAllocator::makeWritable(m_start, m_size); |
55 | } |
56 | |
57 | ~RepatchBuffer() |
58 | { |
59 | ExecutableAllocator::makeExecutable(m_start, m_size); |
60 | } |
61 | |
62 | void relink(CodeLocationJump jump, CodeLocationLabel destination) |
63 | { |
64 | MacroAssembler::repatchJump(jump, destination); |
65 | } |
66 | |
67 | void relink(CodeLocationCall call, CodeLocationLabel destination) |
68 | { |
69 | MacroAssembler::repatchCall(call, destination); |
70 | } |
71 | |
72 | void relink(CodeLocationCall call, FunctionPtr destination) |
73 | { |
74 | MacroAssembler::repatchCall(call, destination); |
75 | } |
76 | |
77 | void relink(CodeLocationNearCall nearCall, CodePtr destination) |
78 | { |
79 | MacroAssembler::repatchNearCall(nearCall, destination: CodeLocationLabel(destination)); |
80 | } |
81 | |
82 | void relink(CodeLocationNearCall nearCall, CodeLocationLabel destination) |
83 | { |
84 | MacroAssembler::repatchNearCall(nearCall, destination); |
85 | } |
86 | |
87 | void repatch(CodeLocationDataLabel32 dataLabel32, int32_t value) |
88 | { |
89 | MacroAssembler::repatchInt32(dataLabel32, value); |
90 | } |
91 | |
92 | void repatch(CodeLocationDataLabelPtr dataLabelPtr, void* value) |
93 | { |
94 | MacroAssembler::repatchPointer(dataLabelPtr, value); |
95 | } |
96 | |
97 | void repatchLoadPtrToLEA(CodeLocationInstruction instruction) |
98 | { |
99 | MacroAssembler::repatchLoadPtrToLEA(instruction); |
100 | } |
101 | |
102 | void relinkCallerToTrampoline(ReturnAddressPtr returnAddress, CodeLocationLabel label) |
103 | { |
104 | relink(call: CodeLocationCall(CodePtr(returnAddress)), destination: label); |
105 | } |
106 | |
107 | void relinkCallerToTrampoline(ReturnAddressPtr returnAddress, CodePtr newCalleeFunction) |
108 | { |
109 | relinkCallerToTrampoline(returnAddress, label: CodeLocationLabel(newCalleeFunction)); |
110 | } |
111 | |
112 | void relinkCallerToFunction(ReturnAddressPtr returnAddress, FunctionPtr function) |
113 | { |
114 | relink(call: CodeLocationCall(CodePtr(returnAddress)), destination: function); |
115 | } |
116 | |
117 | void relinkNearCallerToTrampoline(ReturnAddressPtr returnAddress, CodeLocationLabel label) |
118 | { |
119 | relink(nearCall: CodeLocationNearCall(CodePtr(returnAddress)), destination: label); |
120 | } |
121 | |
122 | void relinkNearCallerToTrampoline(ReturnAddressPtr returnAddress, CodePtr newCalleeFunction) |
123 | { |
124 | relinkNearCallerToTrampoline(returnAddress, label: CodeLocationLabel(newCalleeFunction)); |
125 | } |
126 | |
127 | private: |
128 | void* m_start; |
129 | size_t m_size; |
130 | }; |
131 | |
132 | } // namespace JSC |
133 | |
134 | #endif // ENABLE(ASSEMBLER) |
135 | |
136 | #endif // RepatchBuffer_h |
137 | |