// Copyright 2011 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <assert.h>
#include <stdarg.h>
#include <stdio.h>

#if V8_TARGET_ARCH_IA32

#include "src/base/compiler-specific.h"
#include "src/codegen/ia32/sse-instr.h"
#include "src/diagnostics/disasm.h"
#include "src/utils/utils.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 const ByteMnemonic two_operands_instr[] = {
    {0x01, "add", OPER_REG_OP_ORDER},  {0x03, "add", REG_OPER_OP_ORDER},
    {0x09, "or", OPER_REG_OP_ORDER},   {0x0B, "or", REG_OPER_OP_ORDER},
    {0x13, "adc", REG_OPER_OP_ORDER},  {0x1B, "sbb", REG_OPER_OP_ORDER},
    {0x21, "and", OPER_REG_OP_ORDER},  {0x23, "and", REG_OPER_OP_ORDER},
    {0x29, "sub", OPER_REG_OP_ORDER},  {0x2A, "subb", REG_OPER_OP_ORDER},
    {0x2B, "sub", REG_OPER_OP_ORDER},  {0x31, "xor", OPER_REG_OP_ORDER},
    {0x33, "xor", REG_OPER_OP_ORDER},  {0x38, "cmpb", OPER_REG_OP_ORDER},
    {0x39, "cmp", OPER_REG_OP_ORDER},  {0x3A, "cmpb", REG_OPER_OP_ORDER},
    {0x3B, "cmp", REG_OPER_OP_ORDER},  {0x84, "test_b", REG_OPER_OP_ORDER},
    {0x85, "test", REG_OPER_OP_ORDER}, {0x86, "xchg_b", REG_OPER_OP_ORDER},
    {0x87, "xchg", REG_OPER_OP_ORDER}, {0x8A, "mov_b", REG_OPER_OP_ORDER},
    {0x8B, "mov", REG_OPER_OP_ORDER},  {0x8D, "lea", REG_OPER_OP_ORDER},
    {-1, "", UNSET_OP_ORDER}};

static const 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},
    {0xFC, "cld", UNSET_OP_ORDER},   {0xAB, "stos", UNSET_OP_ORDER},
    {-1, "", UNSET_OP_ORDER}};

static const ByteMnemonic call_jump_instr[] = {{0xE8, "call", UNSET_OP_ORDER},
                                               {0xE9, "jmp", UNSET_OP_ORDER},
                                               {-1, "", UNSET_OP_ORDER}};

static const 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}};

// Generally we don't want to generate these because they are subject to partial
// register stalls.  They are included for completeness and because the cmp
// variant is used by the RecordWrite stub.  Because it does not update the
// register it is not subject to partial register stalls.
static ByteMnemonic byte_immediate_instr[] = {{0x0C, "or", UNSET_OP_ORDER},
                                              {0x24, "and", UNSET_OP_ORDER},
                                              {0x34, "xor", UNSET_OP_ORDER},
                                              {0x3C, "cmp", UNSET_OP_ORDER},
                                              {-1, "", UNSET_OP_ORDER}};

static const char* const 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* const set_conditional_mnem[] = {
    /*0*/ "seto",  "setno", "setc",  "setnc",
    /*4*/ "setz",  "setnz", "setna", "seta",
    /*8*/ "sets",  "setns", "setpe", "setpo",
    /*12*/ "setl", "setnl", "setng", "setg"};

static const char* const conditional_move_mnem[] = {
    /*0*/ "cmovo",  "cmovno", "cmovc",  "cmovnc",
    /*4*/ "cmovz",  "cmovnz", "cmovna", "cmova",
    /*8*/ "cmovs",  "cmovns", "cmovpe", "cmovpo",
    /*12*/ "cmovl", "cmovnl", "cmovng", "cmovg"};

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,
  BYTE_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]; }
  static InstructionTable* get_instance() {
    static InstructionTable table;
    return &table;
  }

 private:
  InstructionDesc instructions_[256];
  void Clear();
  void Init();
  void CopyTable(const 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);
  CopyTable(byte_immediate_instr, BYTE_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(const 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_;
    DCHECK_EQ(NO_INSTR, id->type);  // Information not 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];
    DCHECK_EQ(NO_INSTR, id->type);  // Information not already entered.
    id->mnem = mnem;
    id->type = type;
  }
}

void InstructionTable::AddJumpConditionalShort() {
  for (byte b = 0x70; b <= 0x7F; b++) {
    InstructionDesc* id = &instructions_[b];
    DCHECK_EQ(NO_INSTR, id->type);  // Information not already entered.
    id->mnem = jump_conditional_mnem[b & 0x0F];
    id->type = JUMP_CONDITIONAL_SHORT_INSTR;
  }
}

namespace {
int8_t Imm8(const uint8_t* data) {
  return *reinterpret_cast<const int8_t*>(data);
}
uint8_t Imm8_U(const uint8_t* data) {
  return *reinterpret_cast<const uint8_t*>(data);
}
int16_t Imm16(const uint8_t* data) {
  return *reinterpret_cast<const int16_t*>(data);
}
uint16_t Imm16_U(const uint8_t* data) {
  return *reinterpret_cast<const uint16_t*>(data);
}
int32_t Imm32(const uint8_t* data) {
  return *reinterpret_cast<const int32_t*>(data);
}
}  // namespace

// The IA32 disassembler implementation.
class DisassemblerIA32 {
 public:
  DisassemblerIA32(
      const NameConverter& converter,
      Disassembler::UnimplementedOpcodeAction unimplemented_opcode_action)
      : converter_(converter),
        vex_byte0_(0),
        vex_byte1_(0),
        vex_byte2_(0),
        instruction_table_(InstructionTable::get_instance()),
        tmp_buffer_pos_(0),
        unimplemented_opcode_action_(unimplemented_opcode_action) {
    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_;
  byte vex_byte0_;  // 0xC4 or 0xC5
  byte vex_byte1_;
  byte vex_byte2_;  // only for 3 bytes vex prefix
  InstructionTable* instruction_table_;
  v8::internal::EmbeddedVector<char, 128> tmp_buffer_;
  unsigned int tmp_buffer_pos_;
  Disassembler::UnimplementedOpcodeAction unimplemented_opcode_action_;

  enum {
    eax = 0,
    ecx = 1,
    edx = 2,
    ebx = 3,
    esp = 4,
    ebp = 5,
    esi = 6,
    edi = 7
  };

  enum ShiftOpcodeExtension {
    kROL = 0,
    kROR = 1,
    kRCL = 2,
    kRCR = 3,
    kSHL = 4,
    KSHR = 5,
    kSAR = 7
  };

  bool vex_128() {
    DCHECK(vex_byte0_ == 0xC4 || vex_byte0_ == 0xC5);
    byte checked = vex_byte0_ == 0xC4 ? vex_byte2_ : vex_byte1_;
    return (checked & 4) == 0;
  }

  bool vex_none() {
    DCHECK(vex_byte0_ == 0xC4 || vex_byte0_ == 0xC5);
    byte checked = vex_byte0_ == 0xC4 ? vex_byte2_ : vex_byte1_;
    return (checked & 3) == 0;
  }

  bool vex_66() {
    DCHECK(vex_byte0_ == 0xC4 || vex_byte0_ == 0xC5);
    byte checked = vex_byte0_ == 0xC4 ? vex_byte2_ : vex_byte1_;
    return (checked & 3) == 1;
  }

  bool vex_f3() {
    DCHECK(vex_byte0_ == 0xC4 || vex_byte0_ == 0xC5);
    byte checked = vex_byte0_ == 0xC4 ? vex_byte2_ : vex_byte1_;
    return (checked & 3) == 2;
  }

  bool vex_f2() {
    DCHECK(vex_byte0_ == 0xC4 || vex_byte0_ == 0xC5);
    byte checked = vex_byte0_ == 0xC4 ? vex_byte2_ : vex_byte1_;
    return (checked & 3) == 3;
  }

  bool vex_w() {
    if (vex_byte0_ == 0xC5) return false;
    return (vex_byte2_ & 0x80) != 0;
  }

  bool vex_0f() {
    if (vex_byte0_ == 0xC5) return true;
    return (vex_byte1_ & 3) == 1;
  }

  bool vex_0f38() {
    if (vex_byte0_ == 0xC5) return false;
    return (vex_byte1_ & 3) == 2;
  }

  bool vex_0f3a() {
    if (vex_byte0_ == 0xC5) return false;
    return (vex_byte1_ & 3) == 3;
  }

  int vex_vreg() {
    DCHECK(vex_byte0_ == 0xC4 || vex_byte0_ == 0xC5);
    byte checked = vex_byte0_ == 0xC4 ? vex_byte2_ : vex_byte1_;
    return ~(checked >> 3) & 0xF;
  }

  char float_size_code() { return "sd"[vex_w()]; }

  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;
  }

  using RegisterNameMapping = const char* (DisassemblerIA32::*)(int reg) const;

  int PrintRightOperandHelper(byte* modrmp, RegisterNameMapping register_name);
  int PrintRightOperand(byte* modrmp);
  int PrintRightByteOperand(byte* modrmp);
  int PrintRightXMMOperand(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 CMov(byte* data);
  int FPUInstruction(byte* data);
  int MemoryFPUInstruction(int escape_opcode, int regop, byte* modrm_start);
  int RegisterFPUInstruction(int escape_opcode, byte modrm_byte);
  int AVXInstruction(byte* data);
  PRINTF_FORMAT(2, 3) void AppendToBuffer(const char* format, ...);

  void UnimplementedInstruction() {
    if (unimplemented_opcode_action_ ==
        Disassembler::kAbortOnUnimplementedOpcode) {
      FATAL("Unimplemented instruction in disassembler");
    } 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::VSNPrintF(buf, format, args);
  va_end(args);
  tmp_buffer_pos_ += result;
}

int DisassemblerIA32::PrintRightOperandHelper(
    byte* modrmp, RegisterNameMapping direct_register_name) {
  int mod, regop, rm;
  get_modrm(*modrmp, &mod, &regop, &rm);
  RegisterNameMapping register_name =
      (mod == 3) ? direct_register_name : &DisassemblerIA32::NameOfCPURegister;
  switch (mod) {
    case 0:
      if (rm == ebp) {
        AppendToBuffer("[0x%x]", Imm32(modrmp + 1));
        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 = Imm32(modrmp + 2);
          AppendToBuffer("[%s*%d%s0x%x]", (this->*register_name)(index),
                         1 << scale, disp < 0 ? "-" : "+",
                         disp < 0 ? -disp : 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 ? Imm32(modrmp + 2) : Imm8(modrmp + 2);
        if (index == base && index == rm /*esp*/ && scale == 0 /*times_1*/) {
          AppendToBuffer("[%s%s0x%x]", (this->*register_name)(rm),
                         disp < 0 ? "-" : "+", disp < 0 ? -disp : disp);
        } else {
          AppendToBuffer("[%s+%s*%d%s0x%x]", (this->*register_name)(base),
                         (this->*register_name)(index), 1 << scale,
                         disp < 0 ? "-" : "+", disp < 0 ? -disp : disp);
        }
        return mod == 2 ? 6 : 3;
      } else {
        // No sib.
        int disp = mod == 2 ? Imm32(modrmp + 1) : Imm8(modrmp + 1);
        AppendToBuffer("[%s%s0x%x]", (this->*register_name)(rm),
                       disp < 0 ? "-" : "+", disp < 0 ? -disp : 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);
}

int DisassemblerIA32::PrintRightXMMOperand(byte* modrmp) {
  return PrintRightOperandHelper(modrmp, &DisassemblerIA32::NameOfXMMRegister);
}

// 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();
  }
  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", Imm32(data + 1 + count));
    return 1 + count + 4 /*int32_t*/;
  }
}

// Returns number of bytes used, including *data.
int DisassemblerIA32::F7Instruction(byte* data) {
  DCHECK_EQ(0xF7, *data);
  byte modrm = *++data;
  int mod, regop, rm;
  get_modrm(modrm, &mod, &regop, &rm);
  const char* mnem = nullptr;
  switch (regop) {
    case 0:
      mnem = "test";
      break;
    case 2:
      mnem = "not";
      break;
    case 3:
      mnem = "neg";
      break;
    case 4:
      mnem = "mul";
      break;
    case 5:
      mnem = "imul";
      break;
    case 6:
      mnem = "div";
      break;
    case 7:
      mnem = "idiv";
      break;
    default:
      UnimplementedInstruction();
  }
  AppendToBuffer("%s ", mnem);
  int count = PrintRightOperand(data);
  if (regop == 0) {
    AppendToBuffer(",0x%x", Imm32(data + count));
    count += 4;
  }
  return 1 + count;
}

int DisassemblerIA32::D1D3C1Instruction(byte* data) {
  byte op = *data;
  DCHECK(op == 0xD1 || op == 0xD3 || op == 0xC1);
  byte modrm = *++data;
  int mod, regop, rm;
  get_modrm(modrm, &mod, &regop, &rm);
  int imm8 = -1;
  const char* mnem = nullptr;
  switch (regop) {
    case kROL:
      mnem = "rol";
      break;
    case kROR:
      mnem = "ror";
      break;
    case kRCL:
      mnem = "rcl";
      break;
    case kRCR:
      mnem = "rcr";
      break;
    case kSHL:
      mnem = "shl";
      break;
    case KSHR:
      mnem = "shr";
      break;
    case kSAR:
      mnem = "sar";
      break;
    default:
      UnimplementedInstruction();
  }
  AppendToBuffer("%s ", mnem);
  int count = PrintRightOperand(data);
  if (op == 0xD1) {
    imm8 = 1;
  } else if (op == 0xC1) {
    imm8 = *(data + 1);
    count++;
  } else if (op == 0xD3) {
    // Shift/rotate by cl.
  }
  if (imm8 >= 0) {
    AppendToBuffer(",%d", imm8);
  } else {
    AppendToBuffer(",cl");
  }
  return 1 + count;
}

// Returns number of bytes used, including *data.
int DisassemblerIA32::JumpShort(byte* data) {
  DCHECK_EQ(0xEB, *data);
  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) {
  DCHECK_EQ(0x0F, *data);
  byte cond = *(data + 1) & 0x0F;
  byte* dest = data + Imm32(data + 2) + 6;
  const char* mnem = jump_conditional_mnem[cond];
  AppendToBuffer("%s %s", mnem, NameOfAddress(dest));
  if (comment != nullptr) {
    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 != nullptr) {
    AppendToBuffer(", %s", comment);
  }
  return 2;
}

// Returns number of bytes used, including *data.
int DisassemblerIA32::SetCC(byte* data) {
  DCHECK_EQ(0x0F, *data);
  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::CMov(byte* data) {
  DCHECK_EQ(0x0F, *data);
  byte cond = *(data + 1) & 0x0F;
  const char* mnem = conditional_move_mnem[cond];
  int op_size = PrintOperands(mnem, REG_OPER_OP_ORDER, data + 2);
  return 2 + op_size;  // includes 0x0F
}

const char* sf_str[4] = {"", "rl", "ra", "ll"};

int DisassemblerIA32::AVXInstruction(byte* data) {
  byte opcode = *data;
  byte* current = data + 1;
  if (vex_66() && vex_0f38()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0x99:
        AppendToBuffer("vfmadd132s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xA9:
        AppendToBuffer("vfmadd213s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xB9:
        AppendToBuffer("vfmadd231s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x9B:
        AppendToBuffer("vfmsub132s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xAB:
        AppendToBuffer("vfmsub213s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xBB:
        AppendToBuffer("vfmsub231s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x9D:
        AppendToBuffer("vfnmadd132s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xAD:
        AppendToBuffer("vfnmadd213s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xBD:
        AppendToBuffer("vfnmadd231s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x9F:
        AppendToBuffer("vfnmsub132s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xAF:
        AppendToBuffer("vfnmsub213s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xBF:
        AppendToBuffer("vfnmsub231s%c %s,%s,", float_size_code(),
                       NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xF7:
        AppendToBuffer("shlx %s,", NameOfCPURegister(regop));
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfCPURegister(vvvv));
        break;
#define DECLARE_SSE_AVX_DIS_CASE(instruction, notUsed1, notUsed2, notUsed3, \
                                 opcode)                                    \
  case 0x##opcode: {                                                        \
    AppendToBuffer("v" #instruction " %s,%s,", NameOfXMMRegister(regop),    \
                   NameOfXMMRegister(vvvv));                                \
    current += PrintRightXMMOperand(current);                               \
    break;                                                                  \
  }

        SSSE3_INSTRUCTION_LIST(DECLARE_SSE_AVX_DIS_CASE)
        SSE4_INSTRUCTION_LIST(DECLARE_SSE_AVX_DIS_CASE)
#undef DECLARE_SSE_AVX_DIS_CASE
#define DECLARE_SSE_AVX_RM_DIS_CASE(instruction, notUsed1, notUsed2, notUsed3, \
                                    opcode)                                    \
  case 0x##opcode: {                                                           \
    AppendToBuffer("v" #instruction " %s,", NameOfXMMRegister(regop));         \
    current += PrintRightXMMOperand(current);                                  \
    break;                                                                     \
  }

        SSE4_RM_INSTRUCTION_LIST(DECLARE_SSE_AVX_RM_DIS_CASE)
#undef DECLARE_SSE_AVX_RM_DIS_CASE
      default:
        UnimplementedInstruction();
    }
  } else if (vex_66() && vex_0f3a()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0x0E:
        AppendToBuffer("vpblendw %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(",%d", Imm8_U(current));
        current++;
        break;
      case 0x0F:
        AppendToBuffer("vpalignr %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(",%d", Imm8_U(current));
        current++;
        break;
      case 0x14:
        AppendToBuffer("vpextrb ");
        current += PrintRightOperand(current);
        AppendToBuffer(",%s,%d", NameOfXMMRegister(regop), Imm8(current));
        current++;
        break;
      case 0x15:
        AppendToBuffer("vpextrw ");
        current += PrintRightOperand(current);
        AppendToBuffer(",%s,%d", NameOfXMMRegister(regop), Imm8(current));
        current++;
        break;
      case 0x16:
        AppendToBuffer("vpextrd ");
        current += PrintRightOperand(current);
        AppendToBuffer(",%s,%d", NameOfXMMRegister(regop), Imm8(current));
        current++;
        break;
      case 0x20:
        AppendToBuffer("vpinsrb %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
      case 0x21:
        AppendToBuffer("vinsertps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
      case 0x22:
        AppendToBuffer("vpinsrd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_f2() && vex_0f()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0x51:
        AppendToBuffer("vsqrtsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x58:
        AppendToBuffer("vaddsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x59:
        AppendToBuffer("vmulsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5C:
        AppendToBuffer("vsubsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5D:
        AppendToBuffer("vminsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5E:
        AppendToBuffer("vdivsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5F:
        AppendToBuffer("vmaxsd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x70:
        AppendToBuffer("vpshuflw %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
      case 0x7C:
        AppendToBuffer("vhaddps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_f3() && vex_0f()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0x51:
        AppendToBuffer("vsqrtss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x58:
        AppendToBuffer("vaddss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x59:
        AppendToBuffer("vmulss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5B:
        AppendToBuffer("vcvttps2dq %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5C:
        AppendToBuffer("vsubss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5D:
        AppendToBuffer("vminss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5E:
        AppendToBuffer("vdivss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5F:
        AppendToBuffer("vmaxss %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x6f:
        AppendToBuffer("vmovdqu %s,", NameOfXMMRegister(regop));
        current += PrintRightOperand(current);
        break;
      case 0x70:
        AppendToBuffer("vpshufhw %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
      case 0x7f:
        AppendToBuffer("vmovdqu ");
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfXMMRegister(regop));
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_none() && vex_0f38()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    const char* mnem = "?";
    switch (opcode) {
      case 0xF2:
        AppendToBuffer("andn %s,%s,", NameOfCPURegister(regop),
                       NameOfCPURegister(vvvv));
        current += PrintRightOperand(current);
        break;
      case 0xF5:
        AppendToBuffer("bzhi %s,", NameOfCPURegister(regop));
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfCPURegister(vvvv));
        break;
      case 0xF7:
        AppendToBuffer("bextr %s,", NameOfCPURegister(regop));
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfCPURegister(vvvv));
        break;
      case 0xF3:
        switch (regop) {
          case 1:
            mnem = "blsr";
            break;
          case 2:
            mnem = "blsmsk";
            break;
          case 3:
            mnem = "blsi";
            break;
          default:
            UnimplementedInstruction();
        }
        AppendToBuffer("%s %s,", mnem, NameOfCPURegister(vvvv));
        current += PrintRightOperand(current);
        mnem = "?";
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_f2() && vex_0f38()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0xF5:
        AppendToBuffer("pdep %s,%s,", NameOfCPURegister(regop),
                       NameOfCPURegister(vvvv));
        current += PrintRightOperand(current);
        break;
      case 0xF6:
        AppendToBuffer("mulx %s,%s,", NameOfCPURegister(regop),
                       NameOfCPURegister(vvvv));
        current += PrintRightOperand(current);
        break;
      case 0xF7:
        AppendToBuffer("shrx %s,", NameOfCPURegister(regop));
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfCPURegister(vvvv));
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_f3() && vex_0f38()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0xF5:
        AppendToBuffer("pext %s,%s,", NameOfCPURegister(regop),
                       NameOfCPURegister(vvvv));
        current += PrintRightOperand(current);
        break;
      case 0xF7:
        AppendToBuffer("sarx %s,", NameOfCPURegister(regop));
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfCPURegister(vvvv));
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_f2() && vex_0f3a()) {
    int mod, regop, rm;
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0xF0:
        AppendToBuffer("rorx %s,", NameOfCPURegister(regop));
        current += PrintRightOperand(current);
        AppendToBuffer(",%d", *current & 0x1F);
        current += 1;
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_none() && vex_0f()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0x28:
        AppendToBuffer("vmovaps %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        break;
      case 0x52:
        AppendToBuffer("vrsqrtps %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        break;
      case 0x53:
        AppendToBuffer("vrcpps %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        break;
      case 0x54:
        AppendToBuffer("vandps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x55:
        AppendToBuffer("vandnps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x57:
        AppendToBuffer("vxorps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x58:
        AppendToBuffer("vaddps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x59:
        AppendToBuffer("vmulps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5B:
        AppendToBuffer("vcvtdq2ps %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5C:
        AppendToBuffer("vsubps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5D:
        AppendToBuffer("vminps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5E:
        AppendToBuffer("vdivps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5F:
        AppendToBuffer("vmaxps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0xC2: {
        const char* const pseudo_op[] = {"eq",  "lt",  "le",  "unord",
                                         "neq", "nlt", "nle", "ord"};
        AppendToBuffer("vcmpps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(", (%s)", pseudo_op[*current]);
        current++;
        break;
      }
      case 0xC6:
        AppendToBuffer("vshufps %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(", %d", (*current) & 3);
        current += 1;
        break;
      default:
        UnimplementedInstruction();
    }
  } else if (vex_66() && vex_0f()) {
    int mod, regop, rm, vvvv = vex_vreg();
    get_modrm(*current, &mod, &regop, &rm);
    switch (opcode) {
      case 0x54:
        AppendToBuffer("vandpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x57:
        AppendToBuffer("vxorpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x58:
        AppendToBuffer("vaddpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x59:
        AppendToBuffer("vmulpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5C:
        AppendToBuffer("vsubpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5D:
        AppendToBuffer("vminpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5E:
        AppendToBuffer("vdivpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x5F:
        AppendToBuffer("vmaxpd %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightXMMOperand(current);
        break;
      case 0x6E:
        AppendToBuffer("vmovd %s,", NameOfXMMRegister(regop));
        current += PrintRightOperand(current);
        break;
      case 0x70:
        AppendToBuffer("vpshufd %s,", NameOfXMMRegister(regop));
        current += PrintRightXMMOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
      case 0x71:
        AppendToBuffer("vps%sw %s,%s", sf_str[regop / 2],
                       NameOfXMMRegister(vvvv), NameOfXMMRegister(rm));
        current++;
        AppendToBuffer(",%u", *current++);
        break;
      case 0x72:
        AppendToBuffer("vps%sd %s,%s", sf_str[regop / 2],
                       NameOfXMMRegister(vvvv), NameOfXMMRegister(rm));
        current++;
        AppendToBuffer(",%u", *current++);
        break;
      case 0x7E:
        AppendToBuffer("vmovd ");
        current += PrintRightOperand(current);
        AppendToBuffer(",%s", NameOfXMMRegister(regop));
        break;
      case 0xC4:
        AppendToBuffer("vpinsrw %s,%s,", NameOfXMMRegister(regop),
                       NameOfXMMRegister(vvvv));
        current += PrintRightOperand(current);
        AppendToBuffer(",%d", Imm8(current));
        current++;
        break;
#define DECLARE_SSE_AVX_DIS_CASE(instruction, notUsed1, notUsed2, opcode) \
  case 0x##opcode: {                                                      \
    AppendToBuffer("v" #instruction " %s,%s,", NameOfXMMRegister(regop),  \
                   NameOfXMMRegister(vvvv));                              \
    current += PrintRightXMMOperand(current);                             \
    break;                                                                \
  }

        SSE2_INSTRUCTION_LIST(DECLARE_SSE_AVX_DIS_CASE)
#undef DECLARE_SSE_AVX_DIS_CASE
      default:
        UnimplementedInstruction();
    }
  } else {
    UnimplementedInstruction();
  }

  return static_cast<int>(current - data);
}

// Returns number of bytes used, including *data.
int DisassemblerIA32::FPUInstruction(byte* data) {
  byte escape_opcode = *data;
  DCHECK_EQ(0xD8, escape_opcode & 0xF8);
  byte modrm_byte = *(data + 1);

  if (modrm_byte >= 0xC0) {
    return RegisterFPUInstruction(escape_opcode, modrm_byte);
  } else {
    return MemoryFPUInstruction(escape_opcode, modrm_byte, data + 1);
  }
}

int DisassemblerIA32::MemoryFPUInstruction(int escape_opcode, int modrm_byte,
                                           byte* modrm_start) {
  const char* mnem = "?";
  int regop = (modrm_byte >> 3) & 0x7;  // reg/op field of modrm byte.
  switch (escape_opcode) {
    case 0xD9:
      switch (regop) {
        case 0:
          mnem = "fld_s";
          break;
        case 2:
          mnem = "fst_s";
          break;
        case 3:
          mnem = "fstp_s";
          break;
        case 7:
          mnem = "fstcw";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    case 0xDB:
      switch (regop) {
        case 0:
          mnem = "fild_s";
          break;
        case 1:
          mnem = "fisttp_s";
          break;
        case 2:
          mnem = "fist_s";
          break;
        case 3:
          mnem = "fistp_s";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    case 0xDD:
      switch (regop) {
        case 0:
          mnem = "fld_d";
          break;
        case 1:
          mnem = "fisttp_d";
          break;
        case 2:
          mnem = "fst_d";
          break;
        case 3:
          mnem = "fstp_d";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    case 0xDF:
      switch (regop) {
        case 5:
          mnem = "fild_d";
          break;
        case 7:
          mnem = "fistp_d";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    default:
      UnimplementedInstruction();
  }
  AppendToBuffer("%s ", mnem);
  int count = PrintRightOperand(modrm_start);
  return count + 1;
}

int DisassemblerIA32::RegisterFPUInstruction(int escape_opcode,
                                             byte modrm_byte) {
  bool has_register = false;  // Is the FPU register encoded in modrm_byte?
  const char* mnem = "?";

  switch (escape_opcode) {
    case 0xD8:
      has_register = true;
      switch (modrm_byte & 0xF8) {
        case 0xC0:
          mnem = "fadd_i";
          break;
        case 0xE0:
          mnem = "fsub_i";
          break;
        case 0xC8:
          mnem = "fmul_i";
          break;
        case 0xF0:
          mnem = "fdiv_i";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    case 0xD9:
      switch (modrm_byte & 0xF8) {
        case 0xC0:
          mnem = "fld";
          has_register = true;
          break;
        case 0xC8:
          mnem = "fxch";
          has_register = true;
          break;
        default:
          switch (modrm_byte) {
            case 0xE0:
              mnem = "fchs";
              break;
            case 0xE1:
              mnem = "fabs";
              break;
            case 0xE4:
              mnem = "ftst";
              break;
            case 0xE8:
              mnem = "fld1";
              break;
            case 0xEB:
              mnem = "fldpi";
              break;
            case 0xED:
              mnem = "fldln2";
              break;
            case 0xEE:
              mnem = "fldz";
              break;
            case 0xF0:
              mnem = "f2xm1";
              break;
            case 0xF1:
              mnem = "fyl2x";
              break;
            case 0xF4:
              mnem = "fxtract";
              break;
            case 0xF5:
              mnem = "fprem1";
              break;
            case 0xF7:
              mnem = "fincstp";
              break;
            case 0xF8:
              mnem = "fprem";
              break;
            case 0xFC:
              mnem = "frndint";
              break;
            case 0xFD:
              mnem = "fscale";
              break;
            case 0xFE:
              mnem = "fsin";
              break;
            case 0xFF:
              mnem = "fcos";
              break;
            default:
              UnimplementedInstruction();
          }
      }
      break;

    case 0xDA:
      if (modrm_byte == 0xE9) {
        mnem = "fucompp";
      } else {
        UnimplementedInstruction();
      }
      break;

    case 0xDB:
      if ((modrm_byte & 0xF8) == 0xE8) {
        mnem = "fucomi";
        has_register = true;
      } else if (modrm_byte == 0xE2) {
        mnem = "fclex";
      } else if (modrm_byte == 0xE3) {
        mnem = "fninit";
      } else {
        UnimplementedInstruction();
      }
      break;

    case 0xDC:
      has_register = true;
      switch (modrm_byte & 0xF8) {
        case 0xC0:
          mnem = "fadd";
          break;
        case 0xE8:
          mnem = "fsub";
          break;
        case 0xC8:
          mnem = "fmul";
          break;
        case 0xF8:
          mnem = "fdiv";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    case 0xDD:
      has_register = true;
      switch (modrm_byte & 0xF8) {
        case 0xC0:
          mnem = "ffree";
          break;
        case 0xD0:
          mnem = "fst";
          break;
        case 0xD8:
          mnem = "fstp";
          break;
        default:
          UnimplementedInstruction();
      }
      break;

    case 0xDE:
      if (modrm_byte == 0xD9) {
        mnem = "fcompp";
      } else {
        has_register = true;
        switch (modrm_byte & 0xF8) {
          case 0xC0:
            mnem = "faddp";
            break;
          case 0xE8:
            mnem = "fsubp";
            break;
          case 0xC8:
            mnem = "fmulp";
            break;
          case 0xF8:
            mnem = "fdivp";
            break;
          default:
            UnimplementedInstruction();
        }
      }
      break;

    case 0xDF:
      if (modrm_byte == 0xE0) {
        mnem = "fnstsw_ax";
      } else if ((modrm_byte & 0xF8) == 0xE8) {
        mnem = "fucomip";
        has_register = true;
      }
      break;

    default:
      UnimplementedInstruction();
  }

  if (has_register) {
    AppendToBuffer("%s st%d", mnem, modrm_byte & 0x7);
  } else {
    AppendToBuffer("%s", mnem);
  }
  return 2;
}

// Mnemonics for instructions 0xF0 byte.
// Returns nullptr if the instruction is not handled here.
static const char* F0Mnem(byte f0byte) {
  switch (f0byte) {
    case 0x0B:
      return "ud2";
    case 0x18:
      return "prefetch";
    case 0xA2:
      return "cpuid";
    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 0xA4:
      return "shld";
    case 0xA5:
      return "shld";
    case 0xAD:
      return "shrd";
    case 0xAC:
      return "shrd";  // 3-operand version.
    case 0xAB:
      return "bts";
    case 0xB0:
      return "cmpxchg_b";
    case 0xB1:
      return "cmpxchg";
    case 0xBC:
      return "bsf";
    case 0xBD:
      return "bsr";
    case 0xC7:
      return "cmpxchg8b";
    default:
      return nullptr;
  }
}

// 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 = nullptr;
  // 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++;
  } else if (*data == 0xC4 && *(data + 1) >= 0xC0) {
    vex_byte0_ = *data;
    vex_byte1_ = *(data + 1);
    vex_byte2_ = *(data + 2);
    data += 3;
  } else if (*data == 0xC5 && *(data + 1) >= 0xC0) {
    vex_byte0_ = *data;
    vex_byte1_ = *(data + 1);
    data += 2;
  } else if (*data == 0xF0 /*lock*/) {
    AppendToBuffer("lock ");
    data++;
  }

  bool processed = true;  // Will be set to false if the current instruction
                          // is not in 'instructions' table.
  // Decode AVX instructions.
  if (vex_byte0_ != 0) {
    data += AVXInstruction(data);
  } else {
    const InstructionDesc& idesc = instruction_table_->Get(*data);
    switch (idesc.type) {
      case ZERO_OPERANDS_INSTR:
        AppendToBuffer("%s", 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*>(Imm32(data + 1));
        AppendToBuffer("mov %s,%s", NameOfCPURegister(*data & 0x07),
                       NameOfAddress(addr));
        data += 5;
        break;
      }

      case CALL_JUMP_INSTR: {
        byte* addr = data + Imm32(data + 1) + 5;
        AppendToBuffer("%s %s", idesc.mnem, NameOfAddress(addr));
        data += 5;
        break;
      }

      case SHORT_IMMEDIATE_INSTR: {
        byte* addr = reinterpret_cast<byte*>(Imm32(data + 1));
        AppendToBuffer("%s eax,%s", idesc.mnem, NameOfAddress(addr));
        data += 5;
        break;
      }

      case BYTE_IMMEDIATE_INSTR: {
        AppendToBuffer("%s al,0x%x", idesc.mnem, data[1]);
        data += 2;
        break;
      }

      case NO_INSTR:
        processed = false;
        break;

      default:
        UNIMPLEMENTED();  // This type is not implemented.
    }
  }
  //----------------------------
  if (!processed) {
    switch (*data) {
      case 0xC2:
        AppendToBuffer("ret 0x%x", Imm16_U(data + 1));
        data += 3;
        break;

      case 0x6B: {
        data++;
        data += PrintOperands("imul", REG_OPER_OP_ORDER, data);
        AppendToBuffer(",%d", *data);
        data++;
      } break;

      case 0x69: {
        data++;
        data += PrintOperands("imul", REG_OPER_OP_ORDER, data);
        AppendToBuffer(",%d", Imm32(data));
        data += 4;
      } break;

      case 0xF6: {
        data++;
        int mod, regop, rm;
        get_modrm(*data, &mod, &regop, &rm);
        if (regop == eax) {
          AppendToBuffer("test_b ");
          data += PrintRightByteOperand(data);
          int32_t imm = *data;
          AppendToBuffer(",0x%x", imm);
          data++;
        } else {
          UnimplementedInstruction();
        }
      } 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 == 0x18) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          const char* suffix[] = {"nta", "1", "2", "3"};
          AppendToBuffer("%s%s ", f0mnem, suffix[regop & 0x03]);
          data += PrintRightOperand(data);
        } else if (f0byte == 0x1F && data[2] == 0) {
          AppendToBuffer("nop");  // 3 byte nop.
          data += 3;
        } else if (f0byte == 0x1F && data[2] == 0x40 && data[3] == 0) {
          AppendToBuffer("nop");  // 4 byte nop.
          data += 4;
        } else if (f0byte == 0x1F && data[2] == 0x44 && data[3] == 0 &&
                   data[4] == 0) {
          AppendToBuffer("nop");  // 5 byte nop.
          data += 5;
        } else if (f0byte == 0x1F && data[2] == 0x80 && data[3] == 0 &&
                   data[4] == 0 && data[5] == 0 && data[6] == 0) {
          AppendToBuffer("nop");  // 7 byte nop.
          data += 7;
        } else if (f0byte == 0x1F && data[2] == 0x84 && data[3] == 0 &&
                   data[4] == 0 && data[5] == 0 && data[6] == 0 &&
                   data[7] == 0) {
          AppendToBuffer("nop");  // 8 byte nop.
          data += 8;
        } else if (f0byte == 0x0B || f0byte == 0xA2 || f0byte == 0x31) {
          AppendToBuffer("%s", f0mnem);
          data += 2;
        } else if (f0byte == 0x28) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("movaps %s,%s", NameOfXMMRegister(regop),
                         NameOfXMMRegister(rm));
          data++;
        } else if (f0byte == 0x10 || f0byte == 0x11) {
          data += 2;
          // movups xmm, xmm/m128
          // movups xmm/m128, xmm
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("movups ");
          if (f0byte == 0x11) {
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%s", NameOfXMMRegister(regop));
          } else {
            AppendToBuffer("%s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
          }
        } else if (f0byte == 0x2E) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("ucomiss %s,", NameOfXMMRegister(regop));
          data += PrintRightXMMOperand(data);
        } else if (f0byte >= 0x52 && f0byte <= 0x5F) {
          const char* const pseudo_op[] = {
              "rsqrtps", "rcpps", "andps", "andnps",   "orps",
              "xorps",   "addps", "mulps", "cvtps2pd", "cvtdq2ps",
              "subps",   "minps", "divps", "maxps",
          };

          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("%s %s,", pseudo_op[f0byte - 0x52],
                         NameOfXMMRegister(regop));
          data += PrintRightXMMOperand(data);
        } else if (f0byte == 0x50) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("movmskps %s,%s", NameOfCPURegister(regop),
                         NameOfXMMRegister(rm));
          data++;
        } else if (f0byte == 0xC2) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          const char* const pseudo_op[] = {"eq",  "lt",  "le",  "unord",
                                           "neq", "nlt", "nle", "ord"};
          AppendToBuffer("cmpps %s, ", NameOfXMMRegister(regop));
          data += PrintRightXMMOperand(data);
          AppendToBuffer(", (%s)", pseudo_op[*data]);
          data++;
        } else if (f0byte == 0xC6) {
          // shufps xmm, xmm/m128, imm8
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          int8_t imm8 = static_cast<int8_t>(data[1]);
          AppendToBuffer("shufps %s,%s,%d", NameOfXMMRegister(rm),
                         NameOfXMMRegister(regop), static_cast<int>(imm8));
          data += 2;
        } else if (f0byte >= 0xC8 && f0byte <= 0xCF) {
          // bswap
          data += 2;
          int reg = f0byte - 0xC8;
          AppendToBuffer("bswap %s", NameOfCPURegister(reg));
        } 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 if ((f0byte & 0xF0) == 0x40) {
          data += CMov(data);
        } else if (f0byte == 0xA4 || f0byte == 0xAC) {
          // shld, shrd
          data += 2;
          AppendToBuffer("%s ", f0mnem);
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          int8_t imm8 = static_cast<int8_t>(data[1]);
          data += 2;
          AppendToBuffer("%s,%s,%d", NameOfCPURegister(rm),
                         NameOfCPURegister(regop), static_cast<int>(imm8));
        } else if (f0byte == 0xAB || f0byte == 0xA5 || f0byte == 0xAD) {
          // shrd_cl, shld_cl, bts
          data += 2;
          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 if (f0byte == 0xB0) {
          // cmpxchg_b
          data += 2;
          AppendToBuffer("%s ", f0mnem);
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          data += PrintRightOperand(data);
          AppendToBuffer(",%s", NameOfByteCPURegister(regop));
        } else if (f0byte == 0xB1) {
          // cmpxchg
          data += 2;
          data += PrintOperands(f0mnem, OPER_REG_OP_ORDER, data);
        } else if (f0byte == 0xBC) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("%s %s,", f0mnem, NameOfCPURegister(regop));
          data += PrintRightOperand(data);
        } else if (f0byte == 0xBD) {
          data += 2;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("%s %s,", f0mnem, NameOfCPURegister(regop));
          data += PrintRightOperand(data);
        } else if (f0byte == 0xC7) {
          // cmpxchg8b
          data += 2;
          AppendToBuffer("%s ", f0mnem);
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          data += PrintRightOperand(data);
        } else if (f0byte == 0xAE && (data[2] & 0xF8) == 0xF0) {
          AppendToBuffer("mfence");
          data += 3;
        } else if (f0byte == 0xAE && (data[2] & 0xF8) == 0xE8) {
          AppendToBuffer("lfence");
          data += 3;
        } 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 = nullptr;
        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++;
        if (is_byte) {
          AppendToBuffer("%s ", "mov_b");
          data += PrintRightByteOperand(data);
          int32_t imm = *data;
          AppendToBuffer(",0x%x", imm);
          data++;
        } else {
          AppendToBuffer("%s ", "mov");
          data += PrintRightOperand(data);
          AppendToBuffer(",0x%x", Imm32(data));
          data += 4;
        }
      } break;

      case 0x80: {
        data++;
        int mod, regop, rm;
        get_modrm(*data, &mod, &regop, &rm);
        const char* mnem = nullptr;
        switch (regop) {
          case 5:
            mnem = "subb";
            break;
          case 7:
            mnem = "cmpb";
            break;
          default:
            UnimplementedInstruction();
        }
        AppendToBuffer("%s ", mnem);
        data += PrintRightByteOperand(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);
        if (is_byte) {
          AppendToBuffer("%s ", "mov_b");
          data += PrintRightByteOperand(data);
          AppendToBuffer(",%s", NameOfByteCPURegister(regop));
        } else {
          AppendToBuffer("%s ", "mov");
          data += PrintRightOperand(data);
          AppendToBuffer(",%s", NameOfCPURegister(regop));
        }
      } break;

      case 0x66:  // prefix
        while (*data == 0x66) data++;
        if (*data == 0xF && data[1] == 0x1F) {
          AppendToBuffer("nop");  // 0x66 prefix
        } else if (*data == 0x39) {
          data++;
          data += PrintOperands("cmpw", OPER_REG_OP_ORDER, data);
        } else if (*data == 0x3B) {
          data++;
          data += PrintOperands("cmpw", REG_OPER_OP_ORDER, data);
        } else if (*data == 0x81) {
          data++;
          AppendToBuffer("cmpw ");
          data += PrintRightOperand(data);
          AppendToBuffer(",0x%x", Imm16(data));
          data += 2;
        } else if (*data == 0x87) {
          data++;
          int mod, regop, rm;
          get_modrm(*data, &mod, &regop, &rm);
          AppendToBuffer("xchg_w %s,", NameOfCPURegister(regop));
          data += PrintRightOperand(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 if (*data == 0x8B) {
          data++;
          data += PrintOperands("mov_w", REG_OPER_OP_ORDER, data);
        } else if (*data == 0x90) {
          AppendToBuffer("nop");  // 0x66 prefix
        } else if (*data == 0xC7) {
          data++;
          AppendToBuffer("%s ", "mov_w");
          data += PrintRightOperand(data);
          AppendToBuffer(",0x%x", Imm16(data));
          data += 2;
        } else if (*data == 0xF7) {
          data++;
          AppendToBuffer("%s ", "test_w");
          data += PrintRightOperand(data);
          AppendToBuffer(",0x%x", Imm16(data));
          data += 2;
        } else if (*data == 0x0F) {
          data++;
          if (*data == 0x38) {
            data++;
            byte op = *data;
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            switch (op) {
#define SSE34_DIS_CASE(instruction, notUsed1, notUsed2, notUsed3, opcode) \
  case 0x##opcode: {                                                      \
    AppendToBuffer(#instruction " %s,", NameOfXMMRegister(regop));        \
    data += PrintRightXMMOperand(data);                                   \
    break;                                                                \
  }

              SSSE3_INSTRUCTION_LIST(SSE34_DIS_CASE)
              SSE4_INSTRUCTION_LIST(SSE34_DIS_CASE)
              SSE4_RM_INSTRUCTION_LIST(SSE34_DIS_CASE)
#undef SSE34_DIS_CASE
              default:
                UnimplementedInstruction();
            }
          } else if (*data == 0x3A) {
            data++;
            if (*data == 0x0A) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              int8_t imm8 = static_cast<int8_t>(data[1]);
              AppendToBuffer("roundss %s,%s,%d", NameOfXMMRegister(regop),
                             NameOfXMMRegister(rm), static_cast<int>(imm8));
              data += 2;
            } else if (*data == 0x0B) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              int8_t imm8 = static_cast<int8_t>(data[1]);
              AppendToBuffer("roundsd %s,%s,%d", NameOfXMMRegister(regop),
                             NameOfXMMRegister(rm), static_cast<int>(imm8));
              data += 2;
            } else if (*data == 0x0E) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pblendw %s,", NameOfXMMRegister(regop));
              data += PrintRightXMMOperand(data);
              AppendToBuffer(",%d", Imm8_U(data));
              data++;
            } else if (*data == 0x0F) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("palignr %s,", NameOfXMMRegister(regop));
              data += PrintRightXMMOperand(data);
              AppendToBuffer(",%d", Imm8_U(data));
              data++;
            } else if (*data == 0x14) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pextrb ");
              data += PrintRightOperand(data);
              AppendToBuffer(",%s,%d", NameOfXMMRegister(regop), Imm8(data));
              data++;
            } else if (*data == 0x15) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pextrw ");
              data += PrintRightOperand(data);
              AppendToBuffer(",%s,%d", NameOfXMMRegister(regop), Imm8(data));
              data++;
            } else if (*data == 0x16) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pextrd ");
              data += PrintRightOperand(data);
              AppendToBuffer(",%s,%d", NameOfXMMRegister(regop), Imm8(data));
              data++;
            } else if (*data == 0x17) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              int8_t imm8 = static_cast<int8_t>(data[1]);
              AppendToBuffer("extractps %s,%s,%d", NameOfCPURegister(rm),
                             NameOfXMMRegister(regop), static_cast<int>(imm8));
              data += 2;
            } else if (*data == 0x20) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pinsrb %s,", NameOfXMMRegister(regop));
              data += PrintRightOperand(data);
              AppendToBuffer(",%d", Imm8(data));
              data++;
            } else if (*data == 0x21) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("insertps %s,", NameOfXMMRegister(regop));
              data += PrintRightXMMOperand(data);
              AppendToBuffer(",%d", Imm8(data));
              data++;
            } else if (*data == 0x22) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pinsrd %s,", NameOfXMMRegister(regop));
              data += PrintRightOperand(data);
              AppendToBuffer(",%d", Imm8(data));
              data++;
            } else {
              UnimplementedInstruction();
            }
          } else if (*data == 0x2E || *data == 0x2F) {
            const char* mnem = (*data == 0x2E) ? "ucomisd" : "comisd";
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            if (mod == 0x3) {
              AppendToBuffer("%s %s,%s", mnem, NameOfXMMRegister(regop),
                             NameOfXMMRegister(rm));
              data++;
            } else {
              AppendToBuffer("%s %s,", mnem, NameOfXMMRegister(regop));
              data += PrintRightOperand(data);
            }
          } else if (*data == 0x50) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("movmskpd %s,%s", NameOfCPURegister(regop),
                           NameOfXMMRegister(rm));
            data++;
          } else if (*data == 0x54) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("andpd %s,%s", NameOfXMMRegister(regop),
                           NameOfXMMRegister(rm));
            data++;
          } else if (*data == 0x56) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("orpd %s,%s", NameOfXMMRegister(regop),
                           NameOfXMMRegister(rm));
            data++;
          } else if (*data == 0x57) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("xorpd %s,%s", NameOfXMMRegister(regop),
                           NameOfXMMRegister(rm));
            data++;
          } else if (*data == 0x6E) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("movd %s,", NameOfXMMRegister(regop));
            data += PrintRightOperand(data);
          } else if (*data == 0x6F) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("movdqa %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
          } else if (*data == 0x70) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("pshufd %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%d", Imm8(data));
            data++;
          } else if (*data == 0x90) {
            data++;
            AppendToBuffer("nop");  // 2 byte nop.
          } else if (*data == 0xF3) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("psllq %s,%s", NameOfXMMRegister(regop),
                           NameOfXMMRegister(rm));
            data++;
          } else if (*data == 0x71) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            int8_t imm8 = static_cast<int8_t>(data[1]);
            AppendToBuffer("ps%sw %s,%d", sf_str[regop / 2],
                           NameOfXMMRegister(rm), static_cast<int>(imm8));
            data += 2;
          } else if (*data == 0x72) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            int8_t imm8 = static_cast<int8_t>(data[1]);
            AppendToBuffer("ps%sd %s,%d", sf_str[regop / 2],
                           NameOfXMMRegister(rm), static_cast<int>(imm8));
            data += 2;
          } else if (*data == 0x73) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            int8_t imm8 = static_cast<int8_t>(data[1]);
            DCHECK(regop == esi || regop == edx);
            AppendToBuffer("ps%sq %s,%d", sf_str[regop / 2],
                           NameOfXMMRegister(rm), static_cast<int>(imm8));
            data += 2;
          } else if (*data == 0xD3) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("psrlq %s,%s", NameOfXMMRegister(regop),
                           NameOfXMMRegister(rm));
            data++;
          } else if (*data == 0x7F) {
            AppendToBuffer("movdqa ");
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%s", NameOfXMMRegister(regop));
          } else if (*data == 0x7E) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("movd ");
            data += PrintRightOperand(data);
            AppendToBuffer(",%s", NameOfXMMRegister(regop));
          } else if (*data == 0xC4) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("pinsrw %s,", NameOfXMMRegister(regop));
            data += PrintRightOperand(data);
            AppendToBuffer(",%d", Imm8(data));
            data++;
          } else if (*data == 0xE7) {
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            if (mod == 3) {
              // movntdq
              UnimplementedInstruction();
            } else {
              UnimplementedInstruction();
            }
          } else if (*data == 0xB1) {
            data++;
            data += PrintOperands("cmpxchg_w", OPER_REG_OP_ORDER, data);
          } else {
            byte op = *data;
            data++;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            switch (op) {
#define SSE2_DIS_CASE(instruction, notUsed1, notUsed2, opcode)     \
  case 0x##opcode: {                                               \
    AppendToBuffer(#instruction " %s,", NameOfXMMRegister(regop)); \
    data += PrintRightXMMOperand(data);                            \
    break;                                                         \
  }

              SSE2_INSTRUCTION_LIST(SSE2_DIS_CASE)
#undef SSE2_DIS_CASE
              default:
                UnimplementedInstruction();
            }
          }
        } else {
          UnimplementedInstruction();
        }
        break;

      case 0xFE: {
        data++;
        int mod, regop, rm;
        get_modrm(*data, &mod, &regop, &rm);
        if (regop == ecx) {
          AppendToBuffer("dec_b ");
          data += PrintRightOperand(data);
        } else {
          UnimplementedInstruction();
        }
      } break;

      case 0x68:
        AppendToBuffer("push 0x%x", Imm32(data + 1));
        data += 5;
        break;

      case 0x6A:
        AppendToBuffer("push 0x%x", Imm8(data + 1));
        data += 2;
        break;

      case 0xA8:
        AppendToBuffer("test al,0x%x", Imm8_U(data + 1));
        data += 2;
        break;

      case 0xA9:
        AppendToBuffer("test eax,0x%x", Imm32(data + 1));
        data += 5;
        break;

      case 0xD1:  // fall through
      case 0xD3:  // fall through
      case 0xC1:
        data += D1D3C1Instruction(data);
        break;

      case 0xD8:  // fall through
      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 += PrintRightXMMOperand(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 += PrintRightXMMOperand(data);
          } else if (b2 == 0x5A) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("cvtsd2ss %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
          } else if (b2 == 0x70) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("pshuflw %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%d", Imm8(data));
            data++;
          } else {
            const char* mnem = "?";
            switch (b2) {
              case 0x2A:
                mnem = "cvtsi2sd";
                break;
              case 0x2C:
                mnem = "cvttsd2si";
                break;
              case 0x2D:
                mnem = "cvtsd2si";
                break;
              case 0x51:
                mnem = "sqrtsd";
                break;
              case 0x58:
                mnem = "addsd";
                break;
              case 0x59:
                mnem = "mulsd";
                break;
              case 0x5C:
                mnem = "subsd";
                break;
              case 0x5D:
                mnem = "minsd";
                break;
              case 0x5E:
                mnem = "divsd";
                break;
              case 0x5F:
                mnem = "maxsd";
                break;
              case 0x7C:
                mnem = "haddps";
                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 if (b2 == 0x2C || b2 == 0x2D) {
              AppendToBuffer("%s %s,", mnem, NameOfCPURegister(regop));
              data += PrintRightXMMOperand(data);
            } else if (b2 == 0xC2) {
              // Intel manual 2A, Table 3-18.
              const char* const pseudo_op[] = {
                  "cmpeqsd",  "cmpltsd",  "cmplesd",  "cmpunordsd",
                  "cmpneqsd", "cmpnltsd", "cmpnlesd", "cmpordsd"};
              AppendToBuffer("%s %s,%s", pseudo_op[data[1]],
                             NameOfXMMRegister(regop), NameOfXMMRegister(rm));
              data += 2;
            } else {
              AppendToBuffer("%s %s,", mnem, NameOfXMMRegister(regop));
              data += PrintRightXMMOperand(data);
            }
          }
        } else {
          UnimplementedInstruction();
        }
        break;

      case 0xF3:
        if (*(data + 1) == 0x0F) {
          byte b2 = *(data + 2);
          if (b2 == 0x11) {
            AppendToBuffer("movss ");
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%s", NameOfXMMRegister(regop));
          } else if (b2 == 0x10) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("movss %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
          } else if (b2 == 0x5A) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("cvtss2sd %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
          } else if (b2 == 0x6F) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("movdqu %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
          } else if (b2 == 0x70) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("pshufhw %s,", NameOfXMMRegister(regop));
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%d", Imm8(data));
            data++;
          } else if (b2 == 0x7F) {
            AppendToBuffer("movdqu ");
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            data += PrintRightXMMOperand(data);
            AppendToBuffer(",%s", NameOfXMMRegister(regop));
          } else if (b2 == 0xB8) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("popcnt %s,", NameOfCPURegister(regop));
            data += PrintRightOperand(data);
          } else if (b2 == 0xBC) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("tzcnt %s,", NameOfCPURegister(regop));
            data += PrintRightOperand(data);
          } else if (b2 == 0xBD) {
            data += 3;
            int mod, regop, rm;
            get_modrm(*data, &mod, &regop, &rm);
            AppendToBuffer("lzcnt %s,", NameOfCPURegister(regop));
            data += PrintRightOperand(data);
          } else {
            const char* mnem = "?";
            switch (b2) {
              case 0x2A:
                mnem = "cvtsi2ss";
                break;
              case 0x2C:
                mnem = "cvttss2si";
                break;
              case 0x2D:
                mnem = "cvtss2si";
                break;
              case 0x51:
                mnem = "sqrtss";
                break;
              case 0x58:
                mnem = "addss";
                break;
              case 0x59:
                mnem = "mulss";
                break;
              case 0x5B:
                mnem = "cvttps2dq";
                break;
              case 0x5C:
                mnem = "subss";
                break;
              case 0x5D:
                mnem = "minss";
                break;
              case 0x5E:
                mnem = "divss";
                break;
              case 0x5F:
                mnem = "maxss";
                break;
              case 0x7E:
                mnem = "movq";
                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 if (b2 == 0x2C || b2 == 0x2D) {
              AppendToBuffer("%s %s,", mnem, NameOfCPURegister(regop));
              data += PrintRightXMMOperand(data);
            } else if (b2 == 0xC2) {
              // Intel manual 2A, Table 3-18.
              const char* const pseudo_op[] = {
                  "cmpeqss",  "cmpltss",  "cmpless",  "cmpunordss",
                  "cmpneqss", "cmpnltss", "cmpnless", "cmpordss"};
              AppendToBuffer("%s %s,%s", pseudo_op[data[1]],
                             NameOfXMMRegister(regop), NameOfXMMRegister(rm));
              data += 2;
            } else {
              AppendToBuffer("%s %s,", mnem, NameOfXMMRegister(regop));
              data += PrintRightXMMOperand(data);
            }
          }
        } else if (*(data + 1) == 0xA5) {
          data += 2;
          AppendToBuffer("rep_movs");
        } else if (*(data + 1) == 0xAB) {
          data += 2;
          AppendToBuffer("rep_stos");
        } else if (*(data + 1) == 0x90) {
          data += 2;
          AppendToBuffer("pause");
        } 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;
  if (instr_len == 0) {
    printf("%02x", *data);
  }
  DCHECK_GT(instr_len, 0);  // Ensure progress.

  int outp = 0;
  // Instruction bytes.
  for (byte* bp = instr; bp < data; bp++) {
    outp += v8::internal::SNPrintF(out_buffer + outp, "%02x", *bp);
  }
  for (int i = 6 - instr_len; i >= 0; i--) {
    outp += v8::internal::SNPrintF(out_buffer + outp, "  ");
  }

  outp += v8::internal::SNPrintF(out_buffer + outp, " %s", tmp_buffer_.begin());
  return instr_len;
}  // NOLINT (function is too long)

//------------------------------------------------------------------------------

static const char* const cpu_regs[8] = {"eax", "ecx", "edx", "ebx",
                                        "esp", "ebp", "esi", "edi"};

static const char* const byte_cpu_regs[8] = {"al", "cl", "dl", "bl",
                                             "ah", "ch", "dh", "bh"};

static const char* const xmm_regs[8] = {"xmm0", "xmm1", "xmm2", "xmm3",
                                        "xmm4", "xmm5", "xmm6", "xmm7"};

const char* NameConverter::NameOfAddress(byte* addr) const {
  v8::internal::SNPrintF(tmp_buffer_, "%p", static_cast<void*>(addr));
  return tmp_buffer_.begin();
}

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();
}

//------------------------------------------------------------------------------

int Disassembler::InstructionDecode(v8::internal::Vector<char> buffer,
                                    byte* instruction) {
  DisassemblerIA32 d(converter_, unimplemented_opcode_action());
  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,
                               UnimplementedOpcodeAction unimplemented_action) {
  NameConverter converter;
  Disassembler d(converter, unimplemented_action);
  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", static_cast<void*>(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.begin());
  }
}

}  // namespace disasm

#endif  // V8_TARGET_ARCH_IA32