assembler/CodeLocation.h

   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 CodeLocation_h
  27 #define CodeLocation_h
  28
  29 #include "MacroAssemblerCodeRef.h"
  30
  31 #if ENABLE(ASSEMBLER)
  32
  33 namespace JSC {
  34
  35 class CodeLocationInstruction;
  36 class CodeLocationLabel;
  37 class CodeLocationJump;
  38 class CodeLocationCall;
  39 class CodeLocationNearCall;
  40 class CodeLocationDataLabelCompact;
  41 class CodeLocationDataLabel32;
  42 class CodeLocationDataLabelPtr;
  43
  44 // The CodeLocation* types are all pretty much do-nothing wrappers around
  45 // CodePtr (or MacroAssemblerCodePtr, to give it its full name).  These
  46 // classes only exist to provide type-safety when linking and patching code.
  47 //
  48 // The one new piece of functionallity introduced by these classes is the
  49 // ability to create (or put another way, to re-discover) another CodeLocation
  50 // at an offset from one you already know.  When patching code to optimize it
  51 // we often want to patch a number of instructions that are short, fixed
  52 // offsets apart.  To reduce memory overhead we will only retain a pointer to
  53 // one of the instructions, and we will use the *AtOffset methods provided by
  54 // CodeLocationCommon to find the other points in the code to modify.
  55 class CodeLocationCommon : public MacroAssemblerCodePtr {
  56 public:
  57     CodeLocationInstruction instructionAtOffset(int offset);
  58     CodeLocationLabel labelAtOffset(int offset);
  59     CodeLocationJump jumpAtOffset(int offset);
  60     CodeLocationCall callAtOffset(int offset);
  61     CodeLocationNearCall nearCallAtOffset(int offset);
  62     CodeLocationDataLabelPtr dataLabelPtrAtOffset(int offset);
  63     CodeLocationDataLabel32 dataLabel32AtOffset(int offset);
  64     CodeLocationDataLabelCompact dataLabelCompactAtOffset(int offset);
  65
  66 protected:
  67     CodeLocationCommon()
  68     {
  69     }
  70
  71     CodeLocationCommon(MacroAssemblerCodePtr location)
  72         : MacroAssemblerCodePtr(location)
  73     {
  74     }
  75 };
  76
  77 class CodeLocationInstruction : public CodeLocationCommon {
  78 public:
  79     CodeLocationInstruction() {}
  80     explicit CodeLocationInstruction(MacroAssemblerCodePtr location)
  81         : CodeLocationCommon(location) {}
  82     explicit CodeLocationInstruction(void* location)
  83         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
  84 };
  85
  86 class CodeLocationLabel : public CodeLocationCommon {
  87 public:
  88     CodeLocationLabel() {}
  89     explicit CodeLocationLabel(MacroAssemblerCodePtr location)
  90         : CodeLocationCommon(location) {}
  91     explicit CodeLocationLabel(void* location)
  92         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
  93 };
  94
  95 class CodeLocationJump : public CodeLocationCommon {
  96 public:
  97     CodeLocationJump() {}
  98     explicit CodeLocationJump(MacroAssemblerCodePtr location)
  99         : CodeLocationCommon(location) {}
 100     explicit CodeLocationJump(void* location)
 101         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
 102 };
 103
 104 class CodeLocationCall : public CodeLocationCommon {
 105 public:
 106     CodeLocationCall() {}
 107     explicit CodeLocationCall(MacroAssemblerCodePtr location)
 108         : CodeLocationCommon(location) {}
 109     explicit CodeLocationCall(void* location)
 110         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
 111 };
 112
 113 class CodeLocationNearCall : public CodeLocationCommon {
 114 public:
 115     CodeLocationNearCall() {}
 116     explicit CodeLocationNearCall(MacroAssemblerCodePtr location)
 117         : CodeLocationCommon(location) {}
 118     explicit CodeLocationNearCall(void* location)
 119         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
 120 };
 121
 122 class CodeLocationDataLabel32 : public CodeLocationCommon {
 123 public:
 124     CodeLocationDataLabel32() {}
 125     explicit CodeLocationDataLabel32(MacroAssemblerCodePtr location)
 126         : CodeLocationCommon(location) {}
 127     explicit CodeLocationDataLabel32(void* location)
 128         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
 129 };
 130
 131 class CodeLocationDataLabelCompact : public CodeLocationCommon {
 132 public:
 133     CodeLocationDataLabelCompact() { }
 134     explicit CodeLocationDataLabelCompact(MacroAssemblerCodePtr location)
 135         : CodeLocationCommon(location) { }
 136     explicit CodeLocationDataLabelCompact(void* location)
 137         : CodeLocationCommon(MacroAssemblerCodePtr(location)) { }
 138 };
 139
 140 class CodeLocationDataLabelPtr : public CodeLocationCommon {
 141 public:
 142     CodeLocationDataLabelPtr() {}
 143     explicit CodeLocationDataLabelPtr(MacroAssemblerCodePtr location)
 144         : CodeLocationCommon(location) {}
 145     explicit CodeLocationDataLabelPtr(void* location)
 146         : CodeLocationCommon(MacroAssemblerCodePtr(location)) {}
 147 };
 148
 149 inline CodeLocationInstruction CodeLocationCommon::instructionAtOffset(int offset)
 150 {
 151     ASSERT_VALID_CODE_OFFSET(offset);
 152     return CodeLocationInstruction(reinterpret_cast<char*>(dataLocation()) + offset);
 153 }
 154
 155 inline CodeLocationLabel CodeLocationCommon::labelAtOffset(int offset)
 156 {
 157     ASSERT_VALID_CODE_OFFSET(offset);
 158     return CodeLocationLabel(reinterpret_cast<char*>(dataLocation()) + offset);
 159 }
 160
 161 inline CodeLocationJump CodeLocationCommon::jumpAtOffset(int offset)
 162 {
 163     ASSERT_VALID_CODE_OFFSET(offset);
 164     return CodeLocationJump(reinterpret_cast<char*>(dataLocation()) + offset);
 165 }
 166
 167 inline CodeLocationCall CodeLocationCommon::callAtOffset(int offset)
 168 {
 169     ASSERT_VALID_CODE_OFFSET(offset);
 170     return CodeLocationCall(reinterpret_cast<char*>(dataLocation()) + offset);
 171 }
 172
 173 inline CodeLocationNearCall CodeLocationCommon::nearCallAtOffset(int offset)
 174 {
 175     ASSERT_VALID_CODE_OFFSET(offset);
 176     return CodeLocationNearCall(reinterpret_cast<char*>(dataLocation()) + offset);
 177 }
 178
 179 inline CodeLocationDataLabelPtr CodeLocationCommon::dataLabelPtrAtOffset(int offset)
 180 {
 181     ASSERT_VALID_CODE_OFFSET(offset);
 182     return CodeLocationDataLabelPtr(reinterpret_cast<char*>(dataLocation()) + offset);
 183 }
 184
 185 inline CodeLocationDataLabel32 CodeLocationCommon::dataLabel32AtOffset(int offset)
 186 {
 187     ASSERT_VALID_CODE_OFFSET(offset);
 188     return CodeLocationDataLabel32(reinterpret_cast<char*>(dataLocation()) + offset);
 189 }
 190
 191 inline CodeLocationDataLabelCompact CodeLocationCommon::dataLabelCompactAtOffset(int offset)
 192 {
 193     ASSERT_VALID_CODE_OFFSET(offset);
 194     return CodeLocationDataLabelCompact(reinterpret_cast<char*>(dataLocation()) + offset);
 195 }
 196
 197 } // namespace JSC
 198
 199 #endif // ENABLE(ASSEMBLER)
 200
 201 #endif // CodeLocation_h