Move backend specific files to separate directories.

src/ia32/disasm-ia32.cc

Index: src/ia32/disasm-ia32.cc
diff --git a/src/ia32/disasm-ia32.cc b/src/ia32/disasm-ia32.cc
new file mode 100644
index 0000000000000000000000000000000000000000..458844e050254214b3f44d17c38efc88525bd70d
--- /dev/null
+++ b/src/ia32/disasm-ia32.cc
@@ -0,0 +1,1202 @@
+// Copyright 2007-2008 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * 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.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "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 THE COPYRIGHT
+// OWNER 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.
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdarg.h>
+
+#include "v8.h"
+#include "disasm.h"
+
+namespace disasm {
+
+enum OperandOrder {
+  UNSET_OP_ORDER = 0,
+  REG_OPER_OP_ORDER,
+  OPER_REG_OP_ORDER
+};
+
+
+//------------------------------------------------------------------
+// Tables
+//------------------------------------------------------------------
+struct ByteMnemonic {
+  int b;  // -1 terminates, otherwise must be in range (0..255)
+  const char* mnem;
+  OperandOrder op_order_;
+};
+
+
+static ByteMnemonic two_operands_instr[] = {
+  {0x03, "add", REG_OPER_OP_ORDER},
+  {0x21, "and", OPER_REG_OP_ORDER},
+  {0x23, "and", REG_OPER_OP_ORDER},
+  {0x3B, "cmp", REG_OPER_OP_ORDER},
+  {0x8D, "lea", REG_OPER_OP_ORDER},
+  {0x09, "or", OPER_REG_OP_ORDER},
+  {0x0B, "or", REG_OPER_OP_ORDER},
+  {0x1B, "sbb", REG_OPER_OP_ORDER},
+  {0x29, "sub", OPER_REG_OP_ORDER},
+  {0x2B, "sub", REG_OPER_OP_ORDER},
+  {0x85, "test", REG_OPER_OP_ORDER},
+  {0x31, "xor", OPER_REG_OP_ORDER},
+  {0x33, "xor", REG_OPER_OP_ORDER},
+  {0x87, "xchg", REG_OPER_OP_ORDER},
+  {0x8A, "mov_b", REG_OPER_OP_ORDER},
+  {0x8B, "mov", REG_OPER_OP_ORDER},
+  {-1, "", UNSET_OP_ORDER}
+};
+
+
+static ByteMnemonic zero_operands_instr[] = {
+  {0xC3, "ret", UNSET_OP_ORDER},
+  {0xC9, "leave", UNSET_OP_ORDER},
+  {0x90, "nop", UNSET_OP_ORDER},
+  {0xF4, "hlt", UNSET_OP_ORDER},
+  {0xCC, "int3", UNSET_OP_ORDER},
+  {0x60, "pushad", UNSET_OP_ORDER},
+  {0x61, "popad", UNSET_OP_ORDER},
+  {0x9C, "pushfd", UNSET_OP_ORDER},
+  {0x9D, "popfd", UNSET_OP_ORDER},
+  {0x9E, "sahf", UNSET_OP_ORDER},
+  {0x99, "cdq", UNSET_OP_ORDER},
+  {0x9B, "fwait", UNSET_OP_ORDER},
+  {-1, "", UNSET_OP_ORDER}
+};
+
+
+static ByteMnemonic call_jump_instr[] = {
+  {0xE8, "call", UNSET_OP_ORDER},
+  {0xE9, "jmp", UNSET_OP_ORDER},
+  {-1, "", UNSET_OP_ORDER}
+};
+
+
+static ByteMnemonic short_immediate_instr[] = {
+  {0x05, "add", UNSET_OP_ORDER},
+  {0x0D, "or", UNSET_OP_ORDER},
+  {0x15, "adc", UNSET_OP_ORDER},
+  {0x25, "and", UNSET_OP_ORDER},
+  {0x2D, "sub", UNSET_OP_ORDER},
+  {0x35, "xor", UNSET_OP_ORDER},
+  {0x3D, "cmp", UNSET_OP_ORDER},
+  {-1, "", UNSET_OP_ORDER}
+};
+
+
+static const char* jump_conditional_mnem[] = {
+  /*0*/ "jo", "jno", "jc", "jnc",
+  /*4*/ "jz", "jnz", "jna", "ja",
+  /*8*/ "js", "jns", "jpe", "jpo",
+  /*12*/ "jl", "jnl", "jng", "jg"
+};
+
+
+static const char* set_conditional_mnem[] = {
+  /*0*/ "seto", "setno", "setc", "setnc",
+  /*4*/ "setz", "setnz", "setna", "seta",
+  /*8*/ "sets", "setns", "setpe", "setpo",
+  /*12*/ "setl", "setnl", "setng", "setg"
+};
+
+
+enum InstructionType {
+  NO_INSTR,
+  ZERO_OPERANDS_INSTR,
+  TWO_OPERANDS_INSTR,
+  JUMP_CONDITIONAL_SHORT_INSTR,
+  REGISTER_INSTR,
+  MOVE_REG_INSTR,
+  CALL_JUMP_INSTR,
+  SHORT_IMMEDIATE_INSTR
+};
+
+
+struct InstructionDesc {
+  const char* mnem;
+  InstructionType type;
+  OperandOrder op_order_;
+};
+
+
+class InstructionTable {
+ public:
+  InstructionTable();
+  const InstructionDesc& Get(byte x) const { return instructions_[x]; }
+
+ private:
+  InstructionDesc instructions_[256];
+  void Clear();
+  void Init();
+  void CopyTable(ByteMnemonic bm[], InstructionType type);
+  void SetTableRange(InstructionType type,
+                     byte start,
+                     byte end,
+                     const char* mnem);
+  void AddJumpConditionalShort();
+};
+
+
+InstructionTable::InstructionTable() {
+  Clear();
+  Init();
+}
+
+
+void InstructionTable::Clear() {
+  for (int i = 0; i < 256; i++) {
+    instructions_[i].mnem = "";
+    instructions_[i].type = NO_INSTR;
+    instructions_[i].op_order_ = UNSET_OP_ORDER;
+  }
+}
+
+
+void InstructionTable::Init() {
+  CopyTable(two_operands_instr, TWO_OPERANDS_INSTR);
+  CopyTable(zero_operands_instr, ZERO_OPERANDS_INSTR);
+  CopyTable(call_jump_instr, CALL_JUMP_INSTR);
+  CopyTable(short_immediate_instr, SHORT_IMMEDIATE_INSTR);
+  AddJumpConditionalShort();
+  SetTableRange(REGISTER_INSTR, 0x40, 0x47, "inc");
+  SetTableRange(REGISTER_INSTR, 0x48, 0x4F, "dec");
+  SetTableRange(REGISTER_INSTR, 0x50, 0x57, "push");
+  SetTableRange(REGISTER_INSTR, 0x58, 0x5F, "pop");
+  SetTableRange(REGISTER_INSTR, 0x91, 0x97, "xchg eax,");  // 0x90 is nop.
+  SetTableRange(MOVE_REG_INSTR, 0xB8, 0xBF, "mov");
+}
+
+
+void InstructionTable::CopyTable(ByteMnemonic bm[], InstructionType type) {
+  for (int i = 0; bm[i].b >= 0; i++) {
+    InstructionDesc* id = &instructions_[bm[i].b];
+    id->mnem = bm[i].mnem;
+    id->op_order_ = bm[i].op_order_;
+    assert(id->type == NO_INSTR);  // Information already entered
+    id->type = type;
+  }
+}
+
+
+void InstructionTable::SetTableRange(InstructionType type,
+                                     byte start,
+                                     byte end,
+                                     const char* mnem) {
+  for (byte b = start; b <= end; b++) {
+    InstructionDesc* id = &instructions_[b];
+    assert(id->type == NO_INSTR);  // Information already entered
+    id->mnem = mnem;
+    id->type = type;
+  }
+}
+
+
+void InstructionTable::AddJumpConditionalShort() {
+  for (byte b = 0x70; b <= 0x7F; b++) {
+    InstructionDesc* id = &instructions_[b];
+    assert(id->type == NO_INSTR);  // Information already entered
+    id->mnem = jump_conditional_mnem[b & 0x0F];
+    id->type = JUMP_CONDITIONAL_SHORT_INSTR;
+  }
+}
+
+
+static InstructionTable instruction_table;
+
+
+// The IA32 disassembler implementation.
+class DisassemblerIA32 {
+ public:
+  DisassemblerIA32(const NameConverter& converter,
+                   bool abort_on_unimplemented = true)
+      : converter_(converter),
+        tmp_buffer_pos_(0),
+        abort_on_unimplemented_(abort_on_unimplemented) {
+    tmp_buffer_[0] = '\0';
+  }
+
+  virtual ~DisassemblerIA32() {}
+
+  // Writes one disassembled instruction into 'buffer' (0-terminated).
+  // Returns the length of the disassembled machine instruction in bytes.
+  int InstructionDecode(v8::internal::Vector<char> buffer, byte* instruction);
+
+ private:
+  const NameConverter& converter_;
+  v8::internal::EmbeddedVector<char, 128> tmp_buffer_;
+  unsigned int tmp_buffer_pos_;
+  bool abort_on_unimplemented_;
+
+
+  enum {
+    eax = 0,
+    ecx = 1,
+    edx = 2,
+    ebx = 3,
+    esp = 4,
+    ebp = 5,
+    esi = 6,
+    edi = 7
+  };
+
+
+  const char* NameOfCPURegister(int reg) const {
+    return converter_.NameOfCPURegister(reg);
+  }
+
+
+  const char* NameOfByteCPURegister(int reg) const {
+    return converter_.NameOfByteCPURegister(reg);
+  }
+
+
+  const char* NameOfXMMRegister(int reg) const {
+    return converter_.NameOfXMMRegister(reg);
+  }
+
+
+  const char* NameOfAddress(byte* addr) const {
+    return converter_.NameOfAddress(addr);
+  }
+
+
+  // Disassembler helper functions.
+  static void get_modrm(byte data, int* mod, int* regop, int* rm) {
+    *mod = (data >> 6) & 3;
+    *regop = (data & 0x38) >> 3;
+    *rm = data & 7;
+  }
+
+
+  static void get_sib(byte data, int* scale, int* index, int* base) {
+    *scale = (data >> 6) & 3;
+    *index = (data >> 3) & 7;
+    *base = data & 7;
+  }
+
+  typedef const char* (DisassemblerIA32::*RegisterNameMapping)(int reg) const;
+
+  int PrintRightOperandHelper(byte* modrmp, RegisterNameMapping register_name);
+  int PrintRightOperand(byte* modrmp);
+  int PrintRightByteOperand(byte* modrmp);
+  int PrintOperands(const char* mnem, OperandOrder op_order, byte* data);
+  int PrintImmediateOp(byte* data);
+  int F7Instruction(byte* data);
+  int D1D3C1Instruction(byte* data);
+  int JumpShort(byte* data);
+  int JumpConditional(byte* data, const char* comment);
+  int JumpConditionalShort(byte* data, const char* comment);
+  int SetCC(byte* data);
+  int FPUInstruction(byte* data);
+  void AppendToBuffer(const char* format, ...);
+
+
+  void UnimplementedInstruction() {
+    if (abort_on_unimplemented_) {
+      UNIMPLEMENTED();
+    } else {
+      AppendToBuffer("'Unimplemented Instruction'");
+    }
+  }
+};
+
+
+void DisassemblerIA32::AppendToBuffer(const char* format, ...) {
+  v8::internal::Vector<char> buf = tmp_buffer_ + tmp_buffer_pos_;
+  va_list args;
+  va_start(args, format);
+  int result = v8::internal::OS::VSNPrintF(buf, format, args);
+  va_end(args);
+  tmp_buffer_pos_ += result;
+}
+
+int DisassemblerIA32::PrintRightOperandHelper(
+    byte* modrmp,
+    RegisterNameMapping register_name) {
+  int mod, regop, rm;
+  get_modrm(*modrmp, &mod, &regop, &rm);
+  switch (mod) {
+    case 0:
+      if (rm == ebp) {
+        int32_t disp = *reinterpret_cast<int32_t*>(modrmp+1);
+        AppendToBuffer("[0x%x]", disp);
+        return 5;
+      } else if (rm == esp) {
+        byte sib = *(modrmp + 1);
+        int scale, index, base;
+        get_sib(sib, &scale, &index, &base);
+        if (index == esp && base == esp && scale == 0 /*times_1*/) {
+          AppendToBuffer("[%s]", (this->*register_name)(rm));
+          return 2;
+        } else if (base == ebp) {
+          int32_t disp = *reinterpret_cast<int32_t*>(modrmp + 2);
+          AppendToBuffer("[%s*%d+0x%x]",
+                         (this->*register_name)(index),
+                         1 << scale,
+                         disp);
+          return 6;
+        } else if (index != esp && base != ebp) {
+          // [base+index*scale]
+          AppendToBuffer("[%s+%s*%d]",
+                         (this->*register_name)(base),
+                         (this->*register_name)(index),
+                         1 << scale);
+          return 2;
+        } else {
+          UnimplementedInstruction();
+          return 1;
+        }
+      } else {
+        AppendToBuffer("[%s]", (this->*register_name)(rm));
+        return 1;
+      }
+      break;
+    case 1:  // fall through
+    case 2:
+      if (rm == esp) {
+        byte sib = *(modrmp + 1);
+        int scale, index, base;
+        get_sib(sib, &scale, &index, &base);
+        int disp =
+            mod == 2 ? *reinterpret_cast<int32_t*>(modrmp + 2) : *(modrmp + 2);
+        if (index == base && index == rm /*esp*/ && scale == 0 /*times_1*/) {
+          AppendToBuffer("[%s+0x%x]", (this->*register_name)(rm), disp);
+        } else {
+          AppendToBuffer("[%s+%s*%d+0x%x]",
+                         (this->*register_name)(base),
+                         (this->*register_name)(index),
+                         1 << scale,
+                         disp);
+        }
+        return mod == 2 ? 6 : 3;
+      } else {
+        // No sib.
+        int disp =
+            mod == 2 ? *reinterpret_cast<int32_t*>(modrmp + 1) : *(modrmp + 1);
+        AppendToBuffer("[%s+0x%x]", (this->*register_name)(rm), disp);
+        return mod == 2 ? 5 : 2;
+      }
+      break;
+    case 3:
+      AppendToBuffer("%s", (this->*register_name)(rm));
+      return 1;
+    default:
+      UnimplementedInstruction();
+      return 1;
+  }
+  UNREACHABLE();
+}
+
+
+int DisassemblerIA32::PrintRightOperand(byte* modrmp) {
+  return PrintRightOperandHelper(modrmp, &DisassemblerIA32::NameOfCPURegister);
+}
+
+
+int DisassemblerIA32::PrintRightByteOperand(byte* modrmp) {
+  return PrintRightOperandHelper(modrmp,
+                                 &DisassemblerIA32::NameOfByteCPURegister);
+}
+
+
+// Returns number of bytes used including the current *data.
+// Writes instruction's mnemonic, left and right operands to 'tmp_buffer_'.
+int DisassemblerIA32::PrintOperands(const char* mnem,
+                                    OperandOrder op_order,
+                                    byte* data) {
+  byte modrm = *data;
+  int mod, regop, rm;
+  get_modrm(modrm, &mod, &regop, &rm);
+  int advance = 0;
+  switch (op_order) {
+    case REG_OPER_OP_ORDER: {
+      AppendToBuffer("%s %s,", mnem, NameOfCPURegister(regop));
+      advance = PrintRightOperand(data);
+      break;
+    }
+    case OPER_REG_OP_ORDER: {
+      AppendToBuffer("%s ", mnem);
+      advance = PrintRightOperand(data);
+      AppendToBuffer(",%s", NameOfCPURegister(regop));
+      break;
+    }
+    default:
+      UNREACHABLE();
+      break;
+  }
+  return advance;
+}
+
+
+// Returns number of bytes used by machine instruction, including *data byte.
+// Writes immediate instructions to 'tmp_buffer_'.
+int DisassemblerIA32::PrintImmediateOp(byte* data) {
+  bool sign_extension_bit = (*data & 0x02) != 0;
+  byte modrm = *(data+1);
+  int mod, regop, rm;
+  get_modrm(modrm, &mod, &regop, &rm);
+  const char* mnem = "Imm???";
+  switch (regop) {
+    case 0: mnem = "add"; break;
+    case 1: mnem = "or"; break;
+    case 2: mnem = "adc"; break;
+    case 4: mnem = "and"; break;
+    case 5: mnem = "sub"; break;
+    case 6: mnem = "xor"; break;
+    case 7: mnem = "cmp"; break;
+    default: UnimplementedInstruction();
+  }
+  AppendToBuffer("%s ", mnem);
+  int count = PrintRightOperand(data+1);
+  if (sign_extension_bit) {
+    AppendToBuffer(",0x%x", *(data + 1 + count));
+    return 1 + count + 1 /*int8*/;
+  } else {
+    AppendToBuffer(",0x%x", *reinterpret_cast<int32_t*>(data + 1 + count));
+    return 1 + count + 4 /*int32_t*/;
+  }
+}
+
+
+// Returns number of bytes used, including *data.
+int DisassemblerIA32::F7Instruction(byte* data) {
+  assert(*data == 0xF7);
+  byte modrm = *(data+1);
+  int mod, regop, rm;
+  get_modrm(modrm, &mod, &regop, &rm);
+  if (mod == 3 && regop != 0) {
+    const char* mnem = NULL;
+    switch (regop) {
+      case 2: mnem = "not"; break;
+      case 3: mnem = "neg"; break;
+      case 4: mnem = "mul"; break;
+      case 7: mnem = "idiv"; break;
+      default: UnimplementedInstruction();
+    }
+    AppendToBuffer("%s %s", mnem, NameOfCPURegister(rm));
+    return 2;
+  } else if (mod == 3 && regop == eax) {
+    int32_t imm = *reinterpret_cast<int32_t*>(data+2);
+    AppendToBuffer("test %s,0x%x", NameOfCPURegister(rm), imm);
+    return 6;
+  } else if (regop == eax) {
+    AppendToBuffer("test ");
+    int count = PrintRightOperand(data+1);
+    int32_t imm = *reinterpret_cast<int32_t*>(data+1+count);
+    AppendToBuffer(",0x%x", imm);
+    return 1+count+4 /*int32_t*/;
+  } else {
+    UnimplementedInstruction();
+    return 2;
+  }
+}
+
+int DisassemblerIA32::D1D3C1Instruction(byte* data) {
+  byte op = *data;
+  assert(op == 0xD1 || op == 0xD3 || op == 0xC1);
+  byte modrm = *(data+1);
+  int mod, regop, rm;
+  get_modrm(modrm, &mod, &regop, &rm);
+  int imm8 = -1;
+  int num_bytes = 2;
+  if (mod == 3) {
+    const char* mnem = NULL;
+    if (op == 0xD1) {
+      imm8 = 1;
+      switch (regop) {
+        case edx: mnem = "rcl"; break;
+        case edi: mnem = "sar"; break;
+        case esp: mnem = "shl"; break;
+        default: UnimplementedInstruction();
+      }
+    } else if (op == 0xC1) {
+      imm8 = *(data+2);
+      num_bytes = 3;
+      switch (regop) {
+        case edx: mnem = "rcl"; break;
+        case esp: mnem = "shl"; break;
+        case ebp: mnem = "shr"; break;
+        case edi: mnem = "sar"; break;
+        default: UnimplementedInstruction();
+      }
+    } else if (op == 0xD3) {
+      switch (regop) {
+        case esp: mnem = "shl"; break;
+        case ebp: mnem = "shr"; break;
+        case edi: mnem = "sar"; break;
+        default: UnimplementedInstruction();
+      }
+    }
+    assert(mnem != NULL);
+    AppendToBuffer("%s %s,", mnem, NameOfCPURegister(rm));
+    if (imm8 > 0) {
+      AppendToBuffer("%d", imm8);
+    } else {
+      AppendToBuffer("cl");
+    }
+  } else {
+    UnimplementedInstruction();
+  }
+  return num_bytes;
+}
+
+
+// Returns number of bytes used, including *data.
+int DisassemblerIA32::JumpShort(byte* data) {
+  assert(*data == 0xEB);
+  byte b = *(data+1);
+  byte* dest = data + static_cast<int8_t>(b) + 2;
+  AppendToBuffer("jmp %s", NameOfAddress(dest));
+  return 2;
+}
+
+
+// Returns number of bytes used, including *data.
+int DisassemblerIA32::JumpConditional(byte* data, const char* comment) {
+  assert(*data == 0x0F);
+  byte cond = *(data+1) & 0x0F;
+  byte* dest = data + *reinterpret_cast<int32_t*>(data+2) + 6;
+  const char* mnem = jump_conditional_mnem[cond];
+  AppendToBuffer("%s %s", mnem, NameOfAddress(dest));
+  if (comment != NULL) {
+    AppendToBuffer(", %s", comment);
+  }
+  return 6;  // includes 0x0F
+}
+
+
+// Returns number of bytes used, including *data.
+int DisassemblerIA32::JumpConditionalShort(byte* data, const char* comment) {
+  byte cond = *data & 0x0F;
+  byte b = *(data+1);
+  byte* dest = data + static_cast<int8_t>(b) + 2;
+  const char* mnem = jump_conditional_mnem[cond];
+  AppendToBuffer("%s %s", mnem, NameOfAddress(dest));
+  if (comment != NULL) {
+    AppendToBuffer(", %s", comment);
+  }
+  return 2;
+}
+
+
+// Returns number of bytes used, including *data.
+int DisassemblerIA32::SetCC(byte* data) {
+  assert(*data == 0x0F);
+  byte cond = *(data+1) & 0x0F;
+  const char* mnem = set_conditional_mnem[cond];
+  AppendToBuffer("%s ", mnem);
+  PrintRightByteOperand(data+2);
+  return 3;  // includes 0x0F
+}
+
+
+// Returns number of bytes used, including *data.
+int DisassemblerIA32::FPUInstruction(byte* data) {
+  byte b1 = *data;
+  byte b2 = *(data + 1);
+  if (b1 == 0xD9) {
+    const char* mnem = NULL;
+    switch (b2) {
+      case 0xE8: mnem = "fld1"; break;
+      case 0xEE: mnem = "fldz"; break;
+      case 0xE1: mnem = "fabs"; break;
+      case 0xE0: mnem = "fchs"; break;
+      case 0xF8: mnem = "fprem"; break;
+      case 0xF5: mnem = "fprem1"; break;
+      case 0xF7: mnem = "fincstp"; break;
+      case 0xE4: mnem = "ftst"; break;
+    }
+    if (mnem != NULL) {
+      AppendToBuffer("%s", mnem);
+      return 2;
+    } else if ((b2 & 0xF8) == 0xC8) {
+      AppendToBuffer("fxch st%d", b2 & 0x7);
+      return 2;
+    } else {
+      int mod, regop, rm;
+      get_modrm(*(data+1), &mod, &regop, &rm);
+      const char* mnem = "?";
+      switch (regop) {
+        case eax: mnem = "fld_s"; break;
+        case ebx: mnem = "fstp_s"; break;
+        default: UnimplementedInstruction();
+      }
+      AppendToBuffer("%s ", mnem);
+      int count = PrintRightOperand(data + 1);
+      return count + 1;
+    }
+  } else if (b1 == 0xDD) {
+    if ((b2 & 0xF8) == 0xC0) {
+      AppendToBuffer("ffree st%d", b2 & 0x7);
+      return 2;
+    } else {
+      int mod, regop, rm;
+      get_modrm(*(data+1), &mod, &regop, &rm);
+      const char* mnem = "?";
+      switch (regop) {
+        case eax: mnem = "fld_d"; break;
+        case ebx: mnem = "fstp_d"; break;
+        default: UnimplementedInstruction();
+      }
+      AppendToBuffer("%s ", mnem);
+      int count = PrintRightOperand(data + 1);
+      return count + 1;
+    }
+  } else if (b1 == 0xDB) {
+    int mod, regop, rm;
+    get_modrm(*(data+1), &mod, &regop, &rm);
+    const char* mnem = "?";
+    switch (regop) {
+      case eax: mnem = "fild_s"; break;
+      case edx: mnem = "fist_s"; break;
+      case ebx: mnem = "fistp_s"; break;
+      default: UnimplementedInstruction();
+    }
+    AppendToBuffer("%s ", mnem);
+    int count = PrintRightOperand(data + 1);
+    return count + 1;
+  } else if (b1 == 0xDF) {
+    if (b2 == 0xE0) {
+      AppendToBuffer("fnstsw_ax");
+      return 2;
+    }
+    int mod, regop, rm;
+    get_modrm(*(data+1), &mod, &regop, &rm);
+    const char* mnem = "?";
+    switch (regop) {
+      case ebp: mnem = "fild_d"; break;
+      case edi: mnem = "fistp_d"; break;
+      default: UnimplementedInstruction();
+    }
+    AppendToBuffer("%s ", mnem);
+    int count = PrintRightOperand(data + 1);
+    return count + 1;
+  } else if (b1 == 0xDC || b1 == 0xDE) {
+    bool is_pop = (b1 == 0xDE);
+    if (is_pop && b2 == 0xD9) {
+      AppendToBuffer("fcompp");
+      return 2;
+    }
+    const char* mnem = "FP0xDC";
+    switch (b2 & 0xF8) {
+      case 0xC0: mnem = "fadd"; break;
+      case 0xE8: mnem = "fsub"; break;
+      case 0xC8: mnem = "fmul"; break;
+      case 0xF8: mnem = "fdiv"; break;
+      default: UnimplementedInstruction();
+    }
+    AppendToBuffer("%s%s st%d", mnem, is_pop ? "p" : "", b2 & 0x7);
+    return 2;
+  } else if (b1 == 0xDA && b2 == 0xE9) {
+    const char* mnem = "fucompp";
+    AppendToBuffer("%s", mnem);
+    return 2;
+  }
+  AppendToBuffer("Unknown FP instruction");
+  return 2;
+}
+
+
+// Mnemonics for instructions 0xF0 byte.
+// Returns NULL if the instruction is not handled here.
+static const char* F0Mnem(byte f0byte) {
+  switch (f0byte) {
+    case 0xA2: return "cpuid";
+    case 0x31: return "rdtsc";
+    case 0xBE: return "movsx_b";
+    case 0xBF: return "movsx_w";
+    case 0xB6: return "movzx_b";
+    case 0xB7: return "movzx_w";
+    case 0xAF: return "imul";
+    case 0xA5: return "shld";
+    case 0xAD: return "shrd";
+    case 0xAB: return "bts";
+    default: return NULL;
+  }
+}
+
+
+// Disassembled instruction '*instr' and writes it into 'out_buffer'.
+int DisassemblerIA32::InstructionDecode(v8::internal::Vector<char> out_buffer,
+                                        byte* instr) {
+  tmp_buffer_pos_ = 0;  // starting to write as position 0
+  byte* data = instr;
+  // Check for hints.
+  const char* branch_hint = NULL;
+  // We use these two prefixes only with branch prediction
+  if (*data == 0x3E /*ds*/) {
+    branch_hint = "predicted taken";
+    data++;
+  } else if (*data == 0x2E /*cs*/) {
+    branch_hint = "predicted not taken";
+    data++;
+  }
+  bool processed = true;  // Will be set to false if the current instruction
+                          // is not in 'instructions' table.
+  const InstructionDesc& idesc = instruction_table.Get(*data);
+  switch (idesc.type) {
+    case ZERO_OPERANDS_INSTR:
+      AppendToBuffer(idesc.mnem);
+      data++;
+      break;
+
+    case TWO_OPERANDS_INSTR:
+      data++;
+      data += PrintOperands(idesc.mnem, idesc.op_order_, data);
+      break;
+
+    case JUMP_CONDITIONAL_SHORT_INSTR:
+      data += JumpConditionalShort(data, branch_hint);
+      break;
+
+    case REGISTER_INSTR:
+      AppendToBuffer("%s %s", idesc.mnem, NameOfCPURegister(*data & 0x07));
+      data++;
+      break;
+
+    case MOVE_REG_INSTR: {
+      byte* addr = reinterpret_cast<byte*>(*reinterpret_cast<int32_t*>(data+1));
+      AppendToBuffer("mov %s,%s",
+                     NameOfCPURegister(*data & 0x07),
+                     NameOfAddress(addr));
+      data += 5;
+      break;
+    }
+
+    case CALL_JUMP_INSTR: {
+      byte* addr = data + *reinterpret_cast<int32_t*>(data+1) + 5;
+      AppendToBuffer("%s %s", idesc.mnem, NameOfAddress(addr));
+      data += 5;
+      break;
+    }
+
+    case SHORT_IMMEDIATE_INSTR: {
+      byte* addr = reinterpret_cast<byte*>(*reinterpret_cast<int32_t*>(data+1));
+      AppendToBuffer("%s eax, %s", idesc.mnem, NameOfAddress(addr));
+      data += 5;
+      break;
+    }
+
+    case NO_INSTR:
+      processed = false;
+      break;
+
+    default:
+      UNIMPLEMENTED();  // This type is not implemented.
+  }
+  //----------------------------
+  if (!processed) {
+    switch (*data) {
+      case 0xC2:
+        AppendToBuffer("ret 0x%x", *reinterpret_cast<uint16_t*>(data+1));
+        data += 3;
+        break;
+
+      case 0x69:  // fall through
+      case 0x6B:
+        { int mod, regop, rm;
+          get_modrm(*(data+1), &mod, &regop, &rm);
+          int32_t imm =
+              *data == 0x6B ? *(data+2) : *reinterpret_cast<int32_t*>(data+2);
+          AppendToBuffer("imul %s,%s,0x%x",
+                         NameOfCPURegister(regop),
+                         NameOfCPURegister(rm),
+                         imm);
+          data += 2 + (*data == 0x6B ? 1 : 4);
+        }
+        break;
+
+      case 0xF6:
+        { int mod, regop, rm;
+          get_modrm(*(data+1), &mod, &regop, &rm);
+          if (mod == 3 && regop == eax) {
+            AppendToBuffer("test_b %s,%d", NameOfCPURegister(rm), *(data+2));
+          } else {
+            UnimplementedInstruction();
+          }
+          data += 3;
+        }
+        break;
+
+      case 0x81:  // fall through
+      case 0x83:  // 0x81 with sign extension bit set
+        data += PrintImmediateOp(data);
+        break;
+
+      case 0x0F:
+        { byte f0byte = *(data+1);
+          const char* f0mnem = F0Mnem(f0byte);
+          if (f0byte == 0xA2 || f0byte == 0x31) {
+            AppendToBuffer("%s", f0mnem);
+            data += 2;
+          } else if ((f0byte & 0xF0) == 0x80) {
+            data += JumpConditional(data, branch_hint);
+          } else if (f0byte == 0xBE || f0byte == 0xBF || f0byte == 0xB6 ||
+                     f0byte == 0xB7 || f0byte == 0xAF) {
+            data += 2;
+            data += PrintOperands(f0mnem, REG_OPER_OP_ORDER, data);
+          } else if ((f0byte & 0xF0) == 0x90) {
+            data += SetCC(data);
+          } else {
+            data += 2;
+            if (f0byte == 0xAB || f0byte == 0xA5 || f0byte == 0xAD) {
+              // shrd, shld, bts
+              AppendToBuffer("%s ", f0mnem);
+              int mod, regop, rm;
+              get_modrm(*data, &mod, &regop, &rm);
+              data += PrintRightOperand(data);
+              if (f0byte == 0xAB) {
+                AppendToBuffer(",%s", NameOfCPURegister(regop));
+              } else {
+                AppendToBuffer(",%s,cl", NameOfCPURegister(regop));
+              }
+            } else {
+              UnimplementedInstruction();
+            }
+          }
+        }
+        break;
+
+      case 0x8F:
+        { data++;
+          int mod, regop, rm;
+          get_modrm(*data, &mod, &regop, &rm);
+          if (regop == eax) {
+            AppendToBuffer("pop ");
+            data += PrintRightOperand(data);
+          }
+        }
+        break;
+
+      case 0xFF:
+        { data++;
+          int mod, regop, rm;
+          get_modrm(*data, &mod, &regop, &rm);
+          const char* mnem = NULL;
+          switch (regop) {
+            case esi: mnem = "push"; break;
+            case eax: mnem = "inc"; break;
+            case ecx: mnem = "dec"; break;
+            case edx: mnem = "call"; break;
+            case esp: mnem = "jmp"; break;
+            default: mnem = "???";
+          }
+          AppendToBuffer("%s ", mnem);
+          data += PrintRightOperand(data);
+        }
+        break;
+
+      case 0xC7:  // imm32, fall through
+      case 0xC6:  // imm8
+        { bool is_byte = *data == 0xC6;
+          data++;
+          AppendToBuffer("%s ", is_byte ? "mov_b" : "mov");
+          data += PrintRightOperand(data);
+          int32_t imm = is_byte ? *data : *reinterpret_cast<int32_t*>(data);
+          AppendToBuffer(",0x%x", imm);
+          data += is_byte ? 1 : 4;
+        }
+        break;
+
+      case 0x80:
+        { data++;
+          AppendToBuffer("%s ", "cmpb");
+          data += PrintRightOperand(data);
+          int32_t imm = *data;
+          AppendToBuffer(",0x%x", imm);
+          data++;
+        }
+        break;
+
+      case 0x88:  // 8bit, fall through
+      case 0x89:  // 32bit
+        { bool is_byte = *data == 0x88;
+          int mod, regop, rm;
+          data++;
+          get_modrm(*data, &mod, &regop, &rm);
+          AppendToBuffer("%s ", is_byte ? "mov_b" : "mov");
+          data += PrintRightOperand(data);
+          AppendToBuffer(",%s", NameOfCPURegister(regop));
+        }
+        break;
+
+      case 0x66:  // prefix
+        data++;
+        if (*data == 0x8B) {
+          data++;
+          data += PrintOperands("mov_w", REG_OPER_OP_ORDER, data);
+        } else if (*data == 0x89) {
+          data++;
+          int mod, regop, rm;
+          get_modrm(*data, &mod, &regop, &rm);
+          AppendToBuffer("mov_w ");
+          data += PrintRightOperand(data);
+          AppendToBuffer(",%s", NameOfCPURegister(regop));
+        } else {
+          UnimplementedInstruction();
+        }
+        break;
+
+      case 0xFE:
+        { data++;
+          int mod, regop, rm;
+          get_modrm(*data, &mod, &regop, &rm);
+          if (mod == 3 && regop == ecx) {
+            AppendToBuffer("dec_b %s", NameOfCPURegister(rm));
+          } else {
+            UnimplementedInstruction();
+          }
+          data++;
+        }
+        break;
+
+      case 0x68:
+        AppendToBuffer("push 0x%x", *reinterpret_cast<int32_t*>(data+1));
+        data += 5;
+        break;
+
+      case 0x6A:
+        AppendToBuffer("push 0x%x", *reinterpret_cast<int8_t*>(data + 1));
+        data += 2;
+        break;
+
+      case 0xA8:
+        AppendToBuffer("test al,0x%x", *reinterpret_cast<uint8_t*>(data+1));
+        data += 2;
+        break;
+
+      case 0xA9:
+        AppendToBuffer("test eax,0x%x", *reinterpret_cast<int32_t*>(data+1));
+        data += 5;
+        break;
+
+      case 0xD1:  // fall through
+      case 0xD3:  // fall through
+      case 0xC1:
+        data += D1D3C1Instruction(data);
+        break;
+
+      case 0xD9:  // fall through
+      case 0xDA:  // fall through
+      case 0xDB:  // fall through
+      case 0xDC:  // fall through
+      case 0xDD:  // fall through
+      case 0xDE:  // fall through
+      case 0xDF:
+        data += FPUInstruction(data);
+        break;
+
+      case 0xEB:
+        data += JumpShort(data);
+        break;
+
+      case 0xF2:
+        if (*(data+1) == 0x0F) {
+          byte b2 = *(data+2);
+          if (b2 == 0x11) {
+            AppendToBuffer("movsd ");
+            data += 3;
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            data += PrintRightOperand(data);
+            AppendToBuffer(",%s", NameOfXMMRegister(regop));
+          } else if (b2 == 0x10) {
+            data += 3;
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            AppendToBuffer("movsd %s,", NameOfXMMRegister(regop));
+            data += PrintRightOperand(data);
+          } else {
+            const char* mnem = "?";
+            switch (b2) {
+              case 0x2A: mnem = "cvtsi2sd"; break;
+              case 0x58: mnem = "addsd"; break;
+              case 0x59: mnem = "mulsd"; break;
+              case 0x5C: mnem = "subsd"; break;
+              case 0x5E: mnem = "divsd"; break;
+            }
+            data += 3;
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            if (b2 == 0x2A) {
+              AppendToBuffer("%s %s,", mnem, NameOfXMMRegister(regop));
+              data += PrintRightOperand(data);
+            } else {
+              AppendToBuffer("%s %s,%s",
+                             mnem,
+                             NameOfXMMRegister(regop),
+                             NameOfXMMRegister(rm));
+              data++;
+            }
+          }
+        } else {
+          UnimplementedInstruction();
+        }
+        break;
+
+      case 0xF3:
+        if (*(data+1) == 0x0F && *(data+2) == 0x2C) {
+          data += 3;
+          data += PrintOperands("cvttss2si", REG_OPER_OP_ORDER, data);
+        } else {
+          UnimplementedInstruction();
+        }
+        break;
+
+      case 0xF7:
+        data += F7Instruction(data);
+        break;
+
+      default:
+        UnimplementedInstruction();
+    }
+  }
+
+  if (tmp_buffer_pos_ < sizeof tmp_buffer_) {
+    tmp_buffer_[tmp_buffer_pos_] = '\0';
+  }
+
+  int instr_len = data - instr;
+  ASSERT(instr_len > 0);  // Ensure progress.
+
+  int outp = 0;
+  // Instruction bytes.
+  for (byte* bp = instr; bp < data; bp++) {
+    outp += v8::internal::OS::SNPrintF(out_buffer + outp,
+                                       "%02x",
+                                       *bp);
+  }
+  for (int i = 6 - instr_len; i >= 0; i--) {
+    outp += v8::internal::OS::SNPrintF(out_buffer + outp,
+                                       "  ");
+  }
+
+  outp += v8::internal::OS::SNPrintF(out_buffer + outp,
+                                     " %s",
+                                     tmp_buffer_.start());
+  return instr_len;
+}
+
+
+//------------------------------------------------------------------------------
+
+
+static const char* cpu_regs[8] = {
+  "eax", "ecx", "edx", "ebx", "esp", "ebp", "esi", "edi"
+};
+
+
+static const char* byte_cpu_regs[8] = {
+  "al", "cl", "dl", "bl", "ah", "ch", "dh", "bh"
+};
+
+
+static const char* xmm_regs[8] = {
+  "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7"
+};
+
+
+const char* NameConverter::NameOfAddress(byte* addr) const {
+  static v8::internal::EmbeddedVector<char, 32> tmp_buffer;
+  v8::internal::OS::SNPrintF(tmp_buffer, "%p", addr);
+  return tmp_buffer.start();
+}
+
+
+const char* NameConverter::NameOfConstant(byte* addr) const {
+  return NameOfAddress(addr);
+}
+
+
+const char* NameConverter::NameOfCPURegister(int reg) const {
+  if (0 <= reg && reg < 8) return cpu_regs[reg];
+  return "noreg";
+}
+
+
+const char* NameConverter::NameOfByteCPURegister(int reg) const {
+  if (0 <= reg && reg < 8) return byte_cpu_regs[reg];
+  return "noreg";
+}
+
+
+const char* NameConverter::NameOfXMMRegister(int reg) const {
+  if (0 <= reg && reg < 8) return xmm_regs[reg];
+  return "noxmmreg";
+}
+
+
+const char* NameConverter::NameInCode(byte* addr) const {
+  // IA32 does not embed debug strings at the moment.
+  UNREACHABLE();
+  return "";
+}
+
+
+//------------------------------------------------------------------------------
+
+Disassembler::Disassembler(const NameConverter& converter)
+    : converter_(converter) {}
+
+
+Disassembler::~Disassembler() {}
+
+
+int Disassembler::InstructionDecode(v8::internal::Vector<char> buffer,
+                                    byte* instruction) {
+  DisassemblerIA32 d(converter_, false /*do not crash if unimplemented*/);
+  return d.InstructionDecode(buffer, instruction);
+}
+
+
+// The IA-32 assembler does not currently use constant pools.
+int Disassembler::ConstantPoolSizeAt(byte* instruction) { return -1; }
+
+
+/*static*/ void Disassembler::Disassemble(FILE* f, byte* begin, byte* end) {
+  NameConverter converter;
+  Disassembler d(converter);
+  for (byte* pc = begin; pc < end;) {
+    v8::internal::EmbeddedVector<char, 128> buffer;
+    buffer[0] = '\0';
+    byte* prev_pc = pc;
+    pc += d.InstructionDecode(buffer, pc);
+    fprintf(f, "%p", prev_pc);
+    fprintf(f, "    ");
+
+    for (byte* bp = prev_pc; bp < pc; bp++) {
+      fprintf(f, "%02x",  *bp);
+    }
+    for (int i = 6 - (pc - prev_pc); i >= 0; i--) {
+      fprintf(f, "  ");
+    }
+    fprintf(f, "  %s\n", buffer.start());
+  }
+}
+
+
+}  // namespace disasm