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// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// A combined disassembler for IA32 and X64.
#include "vm/globals.h" // Needed here to get TARGET_ARCH_xxx.
#if defined(TARGET_ARCH_X64) || defined(TARGET_ARCH_IA32)
#include "vm/compiler/assembler/disassembler.h"
#include "platform/unaligned.h"
#include "platform/utils.h"
#include "vm/allocation.h"
#include "vm/constants_x86.h"
#include "vm/heap/heap.h"
#include "vm/instructions.h"
#include "vm/os.h"
#include "vm/stack_frame.h"
#include "vm/stub_code.h"
namespace dart {
#if !defined(PRODUCT) || defined(FORCE_INCLUDE_DISASSEMBLER)
enum OperandType {
UNSET_OP_ORDER = 0,
// Operand size decides between 16, 32 and 64 bit operands.
REG_OPER_OP_ORDER = 1, // Register destination, operand source.
OPER_REG_OP_ORDER = 2, // Operand destination, register source.
// Fixed 8-bit operands.
BYTE_SIZE_OPERAND_FLAG = 4,
BYTE_REG_OPER_OP_ORDER = REG_OPER_OP_ORDER | BYTE_SIZE_OPERAND_FLAG,
BYTE_OPER_REG_OP_ORDER = OPER_REG_OP_ORDER | BYTE_SIZE_OPERAND_FLAG
};
//------------------------------------------------------------------
// Tables
//------------------------------------------------------------------
struct ByteMnemonic {
int b; // -1 terminates, otherwise must be in range (0..255)
OperandType op_order_;
const char* mnem;
};
#define ALU_ENTRY(name, code) \
{code * 8 + 0, BYTE_OPER_REG_OP_ORDER, #name}, \
{code * 8 + 1, OPER_REG_OP_ORDER, #name}, \
{code * 8 + 2, BYTE_REG_OPER_OP_ORDER, #name}, \
{code * 8 + 3, REG_OPER_OP_ORDER, #name},
static const ByteMnemonic two_operands_instr[] = {
X86_ALU_CODES(ALU_ENTRY){0x63, REG_OPER_OP_ORDER, "movsxd"},
{0x84, BYTE_REG_OPER_OP_ORDER, "test"},
{0x85, REG_OPER_OP_ORDER, "test"},
{0x86, BYTE_REG_OPER_OP_ORDER, "xchg"},
{0x87, REG_OPER_OP_ORDER, "xchg"},
{0x88, BYTE_OPER_REG_OP_ORDER, "mov"},
{0x89, OPER_REG_OP_ORDER, "mov"},
{0x8A, BYTE_REG_OPER_OP_ORDER, "mov"},
{0x8B, REG_OPER_OP_ORDER, "mov"},
{0x8D, REG_OPER_OP_ORDER, "lea"},
{-1, UNSET_OP_ORDER, ""}};
#define ZERO_OPERAND_ENTRY(name, opcode) {opcode, UNSET_OP_ORDER, #name},
static const ByteMnemonic zero_operands_instr[] = {
X86_ZERO_OPERAND_1_BYTE_INSTRUCTIONS(ZERO_OPERAND_ENTRY){-1, UNSET_OP_ORDER,
""}};
static const ByteMnemonic call_jump_instr[] = {{0xE8, UNSET_OP_ORDER, "call"},
{0xE9, UNSET_OP_ORDER, "jmp"},
{-1, UNSET_OP_ORDER, ""}};
#define SHORT_IMMEDIATE_ENTRY(name, code) {code * 8 + 5, UNSET_OP_ORDER, #name},
static const ByteMnemonic short_immediate_instr[] = {
X86_ALU_CODES(SHORT_IMMEDIATE_ENTRY){-1, UNSET_OP_ORDER, ""}};
static const char* const conditional_code_suffix[] = {
#define STRINGIFY(name, number) #name,
X86_CONDITIONAL_SUFFIXES(STRINGIFY)
#undef STRINGIFY
};
#define STRINGIFY_NAME(name, code) #name,
static const char* const xmm_conditional_code_suffix[] = {
XMM_CONDITIONAL_CODES(STRINGIFY_NAME)};
#undef STRINGIFY_NAME
enum InstructionType {
NO_INSTR,
ZERO_OPERANDS_INSTR,
TWO_OPERANDS_INSTR,
JUMP_CONDITIONAL_SHORT_INSTR,
REGISTER_INSTR,
PUSHPOP_INSTR, // Has implicit 64-bit operand size.
MOVE_REG_INSTR,
CALL_JUMP_INSTR,
SHORT_IMMEDIATE_INSTR
};
enum Prefixes {
ESCAPE_PREFIX = 0x0F,
OPERAND_SIZE_OVERRIDE_PREFIX = 0x66,
ADDRESS_SIZE_OVERRIDE_PREFIX = 0x67,
REPNE_PREFIX = 0xF2,
REP_PREFIX = 0xF3,
REPEQ_PREFIX = REP_PREFIX
};
struct XmmMnemonic {
const char* ps_name;
const char* pd_name;
const char* ss_name;
const char* sd_name;
};
#define XMM_INSTRUCTION_ENTRY(name, code) \
{#name "ps", #name "pd", #name "ss", #name "sd"},
static const XmmMnemonic xmm_instructions[] = {
XMM_ALU_CODES(XMM_INSTRUCTION_ENTRY)};
struct InstructionDesc {
const char* mnem;
InstructionType type;
OperandType op_order_;
bool byte_size_operation; // Fixed 8-bit operation.
};
class InstructionTable : public ValueObject {
public:
InstructionTable();
const InstructionDesc& Get(uint8_t x) const { return instructions_[x]; }
private:
InstructionDesc instructions_[256];
void Clear();
void Init();
void CopyTable(const ByteMnemonic bm[], InstructionType type);
void SetTableRange(InstructionType type,
uint8_t start,
uint8_t end,
bool byte_size,
const char* mnem);
void AddJumpConditionalShort();
DISALLOW_COPY_AND_ASSIGN(InstructionTable);
};
InstructionTable::InstructionTable() {
Clear();
Init();
}
void InstructionTable::Clear() {
for (int i = 0; i < 256; i++) {
instructions_[i].mnem = "(bad)";
instructions_[i].type = NO_INSTR;
instructions_[i].op_order_ = UNSET_OP_ORDER;
instructions_[i].byte_size_operation = false;
}
}
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(PUSHPOP_INSTR, 0x50, 0x57, false, "push");
SetTableRange(PUSHPOP_INSTR, 0x58, 0x5F, false, "pop");
SetTableRange(MOVE_REG_INSTR, 0xB8, 0xBF, false, "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;
OperandType op_order = bm[i].op_order_;
id->op_order_ =
static_cast<OperandType>(op_order & ~BYTE_SIZE_OPERAND_FLAG);
ASSERT(NO_INSTR == id->type); // Information not already entered
id->type = type;
id->byte_size_operation = ((op_order & BYTE_SIZE_OPERAND_FLAG) != 0);
}
}
void InstructionTable::SetTableRange(InstructionType type,
uint8_t start,
uint8_t end,
bool byte_size,
const char* mnem) {
for (uint8_t b = start; b <= end; b++) {
InstructionDesc* id = &instructions_[b];
ASSERT(NO_INSTR == id->type); // Information not already entered
id->mnem = mnem;
id->type = type;
id->byte_size_operation = byte_size;
}
}
void InstructionTable::AddJumpConditionalShort() {
for (uint8_t b = 0x70; b <= 0x7F; b++) {
InstructionDesc* id = &instructions_[b];
ASSERT(NO_INSTR == id->type); // Information not already entered
id->mnem = NULL; // Computed depending on condition code.
id->type = JUMP_CONDITIONAL_SHORT_INSTR;
}
}
static InstructionTable instruction_table;
static const InstructionDesc cmov_instructions[16] = {
{"cmovo", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovno", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovc", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovnc", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovz", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovnz", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovna", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmova", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovs", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovns", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovpe", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovpo", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovl", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovge", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovle", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false},
{"cmovg", TWO_OPERANDS_INSTR, REG_OPER_OP_ORDER, false}};
//-------------------------------------------------
// DisassemblerX64 implementation.
static const int kMaxXmmRegisters = 16;
static const char* xmm_regs[kMaxXmmRegisters] = {
"xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7",
"xmm8", "xmm9", "xmm10", "xmm11", "xmm12", "xmm13", "xmm14", "xmm15"};
class DisassemblerX64 : public ValueObject {
public:
DisassemblerX64(char* buffer, intptr_t buffer_size)
: buffer_(buffer),
buffer_size_(buffer_size),
buffer_pos_(0),
rex_(0),
operand_size_(0),
group_1_prefix_(0),
byte_size_operand_(false) {
buffer_[buffer_pos_] = '\0';
}
virtual ~DisassemblerX64() {}
int InstructionDecode(uword pc);
private:
enum OperandSize {
BYTE_SIZE = 0,
WORD_SIZE = 1,
DOUBLEWORD_SIZE = 2,
QUADWORD_SIZE = 3
};
void setRex(uint8_t rex) {
ASSERT(0x40 == (rex & 0xF0));
rex_ = rex;
}
bool rex() { return rex_ != 0; }
bool rex_b() { return (rex_ & 0x01) != 0; }
// Actual number of base register given the low bits and the rex.b state.
int base_reg(int low_bits) { return low_bits | ((rex_ & 0x01) << 3); }
bool rex_x() { return (rex_ & 0x02) != 0; }
bool rex_r() { return (rex_ & 0x04) != 0; }
bool rex_w() { return (rex_ & 0x08) != 0; }
OperandSize operand_size() {
if (byte_size_operand_) return BYTE_SIZE;
if (rex_w()) return QUADWORD_SIZE;
if (operand_size_ != 0) return WORD_SIZE;
return DOUBLEWORD_SIZE;
}
const char* operand_size_code() {
#if defined(TARGET_ARCH_X64)
return &"b\0w\0l\0q\0"[2 * operand_size()];
#else
// We omit the 'l' suffix on IA32.
return &"b\0w\0\0\0q\0"[2 * operand_size()];
#endif
}
// Disassembler helper functions.
void get_modrm(uint8_t data, int* mod, int* regop, int* rm) {
*mod = (data >> 6) & 3;
*regop = ((data & 0x38) >> 3) | (rex_r() ? 8 : 0);
*rm = (data & 7) | (rex_b() ? 8 : 0);
ASSERT(*rm < kNumberOfCpuRegisters);
}
void get_sib(uint8_t data, int* scale, int* index, int* base) {
*scale = (data >> 6) & 3;
*index = ((data >> 3) & 7) | (rex_x() ? 8 : 0);
*base = (data & 7) | (rex_b() ? 8 : 0);
ASSERT(*base < kNumberOfCpuRegisters);
}
const char* NameOfCPURegister(int reg) const {
return RegisterNames::RegisterName(static_cast<Register>(reg));
}
const char* NameOfByteCPURegister(int reg) const {
return NameOfCPURegister(reg);
}
// A way to get rax or eax's name.
const char* Rax() const { return NameOfCPURegister(0); }
const char* NameOfXMMRegister(int reg) const {
ASSERT((0 <= reg) && (reg < kMaxXmmRegisters));
return xmm_regs[reg];
}
void Print(const char* format, ...) PRINTF_ATTRIBUTE(2, 3);
void PrintJump(uint8_t* pc, int32_t disp);
void PrintAddress(uint8_t* addr);
int PrintOperands(const char* mnem, OperandType op_order, uint8_t* data);
typedef const char* (DisassemblerX64::*RegisterNameMapping)(int reg) const;
int PrintRightOperandHelper(uint8_t* modrmp,
RegisterNameMapping register_name);
int PrintRightOperand(uint8_t* modrmp);
int PrintRightByteOperand(uint8_t* modrmp);
int PrintRightXMMOperand(uint8_t* modrmp);
void PrintDisp(int disp, const char* after);
int PrintImmediate(uint8_t* data, OperandSize size, bool sign_extend = false);
void PrintImmediateValue(int64_t value,
bool signed_value = false,
int byte_count = -1);
int PrintImmediateOp(uint8_t* data);
const char* TwoByteMnemonic(uint8_t opcode);
int TwoByteOpcodeInstruction(uint8_t* data);
int Print660F38Instruction(uint8_t* data);
int F6F7Instruction(uint8_t* data);
int ShiftInstruction(uint8_t* data);
int JumpShort(uint8_t* data);
int JumpConditional(uint8_t* data);
int JumpConditionalShort(uint8_t* data);
int SetCC(uint8_t* data);
int FPUInstruction(uint8_t* data);
int MemoryFPUInstruction(int escape_opcode, int regop, uint8_t* modrm_start);
int RegisterFPUInstruction(int escape_opcode, uint8_t modrm_byte);
bool DecodeInstructionType(uint8_t** data);
void UnimplementedInstruction() { UNREACHABLE(); }
char* buffer_; // Decode instructions into this buffer.
intptr_t buffer_size_; // The size of the buffer_.
intptr_t buffer_pos_; // Current character position in the buffer_.
// Prefixes parsed
uint8_t rex_;
uint8_t operand_size_; // 0x66 or (if no group 3 prefix is present) 0x0.
// 0xF2, 0xF3, or (if no group 1 prefix is present) 0.
uint8_t group_1_prefix_;
// Byte size operand override.
bool byte_size_operand_;
DISALLOW_COPY_AND_ASSIGN(DisassemblerX64);
};
// Append the str to the output buffer.
void DisassemblerX64::Print(const char* format, ...) {
intptr_t available = buffer_size_ - buffer_pos_;
if (available <= 1) {
ASSERT(buffer_[buffer_pos_] == '\0');
return;
}
char* buf = buffer_ + buffer_pos_;
va_list args;
va_start(args, format);
int length = Utils::VSNPrint(buf, available, format, args);
va_end(args);
buffer_pos_ =
(length >= available) ? (buffer_size_ - 1) : (buffer_pos_ + length);
ASSERT(buffer_pos_ < buffer_size_);
}
int DisassemblerX64::PrintRightOperandHelper(
uint8_t* modrmp,
RegisterNameMapping direct_register_name) {
int mod, regop, rm;
get_modrm(*modrmp, &mod, &regop, &rm);
RegisterNameMapping register_name =
(mod == 3) ? direct_register_name : &DisassemblerX64::NameOfCPURegister;
switch (mod) {
case 0:
if ((rm & 7) == 5) {
#if defined(TARGET_ARCH_IA32)
int32_t abs = LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 1));
Print("[%#x]", abs);
#else
int32_t disp = LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 1));
Print("[rip");
PrintDisp(disp, "]");
#endif
return 5;
} else if ((rm & 7) == 4) {
// Codes for SIB byte.
uint8_t sib = *(modrmp + 1);
int scale, index, base;
get_sib(sib, &scale, &index, &base);
if (index == 4 && (base & 7) == 4 && scale == 0 /*times_1*/) {
// index == rsp means no index. Only use sib byte with no index for
// rsp and r12 base.
Print("[%s]", NameOfCPURegister(base));
return 2;
} else if (base == 5) {
// base == rbp means no base register (when mod == 0).
int32_t disp = LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 2));
Print("[%s*%d", NameOfCPURegister(index), 1 << scale);
PrintDisp(disp, "]");
return 6;
} else if (index != 4 && base != 5) {
// [base+index*scale]
Print("[%s+%s*%d]", NameOfCPURegister(base), NameOfCPURegister(index),
1 << scale);
return 2;
} else {
UnimplementedInstruction();
return 1;
}
} else {
Print("[%s]", NameOfCPURegister(rm));
return 1;
}
break;
case 1:
FALL_THROUGH;
case 2:
if ((rm & 7) == 4) {
uint8_t sib = *(modrmp + 1);
int scale, index, base;
get_sib(sib, &scale, &index, &base);
int disp = (mod == 2)
? LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 2))
: *reinterpret_cast<int8_t*>(modrmp + 2);
if (index == 4 && (base & 7) == 4 && scale == 0 /*times_1*/) {
Print("[%s", NameOfCPURegister(base));
PrintDisp(disp, "]");
} else {
Print("[%s+%s*%d", NameOfCPURegister(base), NameOfCPURegister(index),
1 << scale);
PrintDisp(disp, "]");
}
return mod == 2 ? 6 : 3;
} else {
// No sib.
int disp = (mod == 2)
? LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 1))
: *reinterpret_cast<int8_t*>(modrmp + 1);
Print("[%s", NameOfCPURegister(rm));
PrintDisp(disp, "]");
return (mod == 2) ? 5 : 2;
}
break;
case 3:
Print("%s", (this->*register_name)(rm));
return 1;
default:
UnimplementedInstruction();
return 1;
}
UNREACHABLE();
}
int DisassemblerX64::PrintImmediate(uint8_t* data,
OperandSize size,
bool sign_extend) {
int64_t value;
int count;
switch (size) {
case BYTE_SIZE:
if (sign_extend) {
value = *reinterpret_cast<int8_t*>(data);
} else {
value = *data;
}
count = 1;
break;
case WORD_SIZE:
if (sign_extend) {
value = LoadUnaligned(reinterpret_cast<int16_t*>(data));
} else {
value = LoadUnaligned(reinterpret_cast<uint16_t*>(data));
}
count = 2;
break;
case DOUBLEWORD_SIZE:
case QUADWORD_SIZE:
if (sign_extend) {
value = LoadUnaligned(reinterpret_cast<int32_t*>(data));
} else {
value = LoadUnaligned(reinterpret_cast<uint32_t*>(data));
}
count = 4;
break;
default:
UNREACHABLE();
value = 0; // Initialize variables on all paths to satisfy the compiler.
count = 0;
}
PrintImmediateValue(value, sign_extend, count);
return count;
}
void DisassemblerX64::PrintImmediateValue(int64_t value,
bool signed_value,
int byte_count) {
if ((value >= 0) && (value <= 9)) {
Print("%" Pd64, value);
} else if (signed_value && (value < 0) && (value >= -9)) {
Print("-%" Pd64, -value);
} else {
if (byte_count == 1) {
int8_t v8 = static_cast<int8_t>(value);
if (v8 < 0 && signed_value) {
Print("-%#" Px32, -static_cast<uint8_t>(v8));
} else {
Print("%#" Px32, static_cast<uint8_t>(v8));
}
} else if (byte_count == 2) {
int16_t v16 = static_cast<int16_t>(value);
if (v16 < 0 && signed_value) {
Print("-%#" Px32, -static_cast<uint16_t>(v16));
} else {
Print("%#" Px32, static_cast<uint16_t>(v16));
}
} else if (byte_count == 4) {
int32_t v32 = static_cast<int32_t>(value);
if (v32 < 0 && signed_value) {
Print("-%#010" Px32, -static_cast<uint32_t>(v32));
} else {
if (v32 > 0xffff) {
Print("%#010" Px32, v32);
} else {
Print("%#" Px32, v32);
}
}
} else if (byte_count == 8) {
int64_t v64 = static_cast<int64_t>(value);
if (v64 < 0 && signed_value) {
Print("-%#018" Px64, -static_cast<uint64_t>(v64));
} else {
if (v64 > 0xffffffffll) {
Print("%#018" Px64, v64);
} else {
Print("%#" Px64, v64);
}
}
} else {
// Natural-sized immediates.
#if defined(TARGET_ARCH_X64)
if (value < 0 && signed_value) {
Print("-%#" Px64, -value);
} else {
Print("%#" Px64, value);
}
#else
int32_t v32 = static_cast<int32_t>(value);
if (v32 < 0 && signed_value) {
Print("-%#" Px32, -v32);
} else {
Print("%#" Px32, v32);
}
#endif
}
}
}
void DisassemblerX64::PrintDisp(int disp, const char* after) {
if (-disp > 0) {
Print("-%#x", -disp);
} else {
Print("+%#x", disp);
}
if (after != NULL) Print("%s", after);
}
// Returns number of bytes used by machine instruction, including *data byte.
// Writes immediate instructions to 'tmp_buffer_'.
int DisassemblerX64::PrintImmediateOp(uint8_t* data) {
bool byte_size_immediate = (*data & 0x03) != 1;
uint8_t 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 3:
mnem = "sbb";
break;
case 4:
mnem = "and";
break;
case 5:
mnem = "sub";
break;
case 6:
mnem = "xor";
break;
case 7:
mnem = "cmp";
break;
default:
UnimplementedInstruction();
}
Print("%s%s ", mnem, operand_size_code());
int count = PrintRightOperand(data + 1);
Print(",");
OperandSize immediate_size = byte_size_immediate ? BYTE_SIZE : operand_size();
count +=
PrintImmediate(data + 1 + count, immediate_size, byte_size_immediate);
return 1 + count;
}
// Returns number of bytes used, including *data.
int DisassemblerX64::F6F7Instruction(uint8_t* data) {
ASSERT(*data == 0xF7 || *data == 0xF6);
uint8_t modrm = *(data + 1);
int mod, regop, rm;
get_modrm(modrm, &mod, &regop, &rm);
static const char* const mnemonics[] = {"test", NULL, "not", "neg",
"mul", "imul", "div", "idiv"};
const char* mnem = mnemonics[regop];
if (mod == 3 && regop != 0) {
if (regop > 3) {
// These are instructions like idiv that implicitly use EAX and EDX as a
// source and destination. We make this explicit in the disassembly.
Print("%s%s (%s,%s),%s", mnem, operand_size_code(), Rax(),
NameOfCPURegister(2), NameOfCPURegister(rm));
} else {
Print("%s%s %s", mnem, operand_size_code(), NameOfCPURegister(rm));
}
return 2;
} else if (regop == 0) {
Print("test%s ", operand_size_code());
int count = PrintRightOperand(data + 1); // Use name of 64-bit register.
Print(",");
count += PrintImmediate(data + 1 + count, operand_size());
return 1 + count;
} else if (regop >= 4) {
Print("%s%s (%s,%s),", mnem, operand_size_code(), Rax(),
NameOfCPURegister(2));
return 1 + PrintRightOperand(data + 1);
} else {
UnimplementedInstruction();
return 2;
}
}
int DisassemblerX64::ShiftInstruction(uint8_t* data) {
// C0/C1: Shift Imm8
// D0/D1: Shift 1
// D2/D3: Shift CL
uint8_t op = *data & (~1);
if (op != 0xD0 && op != 0xD2 && op != 0xC0) {
UnimplementedInstruction();
return 1;
}
uint8_t* modrm = data + 1;
int mod, regop, rm;
get_modrm(*modrm, &mod, &regop, &rm);
regop &= 0x7; // The REX.R bit does not affect the operation.
int num_bytes = 1;
const char* mnem = NULL;
switch (regop) {
case 0:
mnem = "rol";
break;
case 1:
mnem = "ror";
break;
case 2:
mnem = "rcl";
break;
case 3:
mnem = "rcr";
break;
case 4:
mnem = "shl";
break;
case 5:
mnem = "shr";
break;
case 7:
mnem = "sar";
break;
default:
UnimplementedInstruction();
return num_bytes;
}
ASSERT(NULL != mnem);
Print("%s%s ", mnem, operand_size_code());
if (byte_size_operand_) {
num_bytes += PrintRightByteOperand(modrm);
} else {
num_bytes += PrintRightOperand(modrm);
}
if (op == 0xD0) {
Print(",1");
} else if (op == 0xC0) {
uint8_t imm8 = *(data + num_bytes);
Print(",%d", imm8);
num_bytes++;
} else {
ASSERT(op == 0xD2);
Print(",cl");
}
return num_bytes;
}
int DisassemblerX64::PrintRightOperand(uint8_t* modrmp) {
return PrintRightOperandHelper(modrmp, &DisassemblerX64::NameOfCPURegister);
}
int DisassemblerX64::PrintRightByteOperand(uint8_t* modrmp) {
return PrintRightOperandHelper(modrmp,
&DisassemblerX64::NameOfByteCPURegister);
}
int DisassemblerX64::PrintRightXMMOperand(uint8_t* modrmp) {
return PrintRightOperandHelper(modrmp, &DisassemblerX64::NameOfXMMRegister);
}
// Returns number of bytes used including the current *data.
// Writes instruction's mnemonic, left and right operands to 'tmp_buffer_'.
int DisassemblerX64::PrintOperands(const char* mnem,
OperandType op_order,
uint8_t* data) {
uint8_t modrm = *data;
int mod, regop, rm;
get_modrm(modrm, &mod, &regop, &rm);
int advance = 0;
const char* register_name = byte_size_operand_ ? NameOfByteCPURegister(regop)
: NameOfCPURegister(regop);
switch (op_order) {
case REG_OPER_OP_ORDER: {
Print("%s%s %s,", mnem, operand_size_code(), register_name);
advance = byte_size_operand_ ? PrintRightByteOperand(data)
: PrintRightOperand(data);
break;
}
case OPER_REG_OP_ORDER: {
Print("%s%s ", mnem, operand_size_code());
advance = byte_size_operand_ ? PrintRightByteOperand(data)
: PrintRightOperand(data);
Print(",%s", register_name);
break;
}
default:
UNREACHABLE();
break;
}
return advance;
}
void DisassemblerX64::PrintJump(uint8_t* pc, int32_t disp) {
if (FLAG_disassemble_relative) {
Print("%+d", disp);
} else {
PrintAddress(
reinterpret_cast<uint8_t*>(reinterpret_cast<uintptr_t>(pc) + disp));
}
}
void DisassemblerX64::PrintAddress(uint8_t* addr_byte_ptr) {
#if defined(TARGET_ARCH_X64)
Print("%#018" Px64 "", reinterpret_cast<uint64_t>(addr_byte_ptr));
#else
Print("%#010" Px32 "", reinterpret_cast<uint32_t>(addr_byte_ptr));
#endif
// Try to print as stub name.
uword addr = reinterpret_cast<uword>(addr_byte_ptr);
const char* name_of_stub = StubCode::NameOfStub(addr);
if (name_of_stub != NULL) {
Print(" [stub: %s]", name_of_stub);
}
}
// Returns number of bytes used, including *data.
int DisassemblerX64::JumpShort(uint8_t* data) {
ASSERT(0xEB == *data);
uint8_t b = *(data + 1);
int32_t disp = static_cast<int8_t>(b) + 2;
Print("jmp ");
PrintJump(data, disp);
return 2;
}
// Returns number of bytes used, including *data.
int DisassemblerX64::JumpConditional(uint8_t* data) {
ASSERT(0x0F == *data);
uint8_t cond = *(data + 1) & 0x0F;
int32_t disp = LoadUnaligned(reinterpret_cast<int32_t*>(data + 2)) + 6;
const char* mnem = conditional_code_suffix[cond];
Print("j%s ", mnem);
PrintJump(data, disp);
return 6; // includes 0x0F
}
// Returns number of bytes used, including *data.
int DisassemblerX64::JumpConditionalShort(uint8_t* data) {
uint8_t cond = *data & 0x0F;
uint8_t b = *(data + 1);
int32_t disp = static_cast<int8_t>(b) + 2;
const char* mnem = conditional_code_suffix[cond];
Print("j%s ", mnem);
PrintJump(data, disp);
return 2;
}
// Returns number of bytes used, including *data.
int DisassemblerX64::SetCC(uint8_t* data) {
ASSERT(0x0F == *data);
uint8_t cond = *(data + 1) & 0x0F;
const char* mnem = conditional_code_suffix[cond];
Print("set%s%s ", mnem, operand_size_code());
PrintRightByteOperand(data + 2);
return 3; // includes 0x0F
}
// Returns number of bytes used, including *data.
int DisassemblerX64::FPUInstruction(uint8_t* data) {
uint8_t escape_opcode = *data;
ASSERT(0xD8 == (escape_opcode & 0xF8));
uint8_t modrm_byte = *(data + 1);
if (modrm_byte >= 0xC0) {
return RegisterFPUInstruction(escape_opcode, modrm_byte);
} else {
return MemoryFPUInstruction(escape_opcode, modrm_byte, data + 1);
}
}
int DisassemblerX64::MemoryFPUInstruction(int escape_opcode,
int modrm_byte,
uint8_t* 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 3:
mnem = "fstp_s";
break;
case 5:
mnem = "fldcw";
break;
case 7:
mnem = "fnstcw";
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 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();
}
Print("%s ", mnem);
int count = PrintRightOperand(modrm_start);
return count + 1;
}
int DisassemblerX64::RegisterFPUInstruction(int escape_opcode,
uint8_t modrm_byte) {
bool has_register = false; // Is the FPU register encoded in modrm_byte?
const char* mnem = "?";
switch (escape_opcode) {
case 0xD8:
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 0xE3:
mnem = "fninit";
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 0xF2:
mnem = "fptan";
break;
case 0xF5:
mnem = "fprem1";
break;
case 0xF7:
mnem = "fincstp";
break;
case 0xF8:
mnem = "fprem";
break;
case 0xFB:
mnem = "fsincos";
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 {
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 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) {
Print("%s st%d", mnem, modrm_byte & 0x7);
} else {
Print("%s", mnem);
}
return 2;
}
// TODO(srdjan): Should we add a branch hint argument?
bool DisassemblerX64::DecodeInstructionType(uint8_t** data) {
uint8_t current;
// Scan for prefixes.
while (true) {
current = **data;
if (current == OPERAND_SIZE_OVERRIDE_PREFIX) { // Group 3 prefix.
operand_size_ = current;
#if defined(TARGET_ARCH_X64)
} else if ((current & 0xF0) == 0x40) {
// REX prefix.
setRex(current);
// TODO(srdjan): Should we enable printing of REX.W?
// if (rex_w()) Print("REX.W ");
#endif
} else if ((current & 0xFE) == 0xF2) { // Group 1 prefix (0xF2 or 0xF3).
group_1_prefix_ = current;
} else if (current == 0xF0) {
Print("lock ");
} else { // Not a prefix - an opcode.
break;
}
(*data)++;
}
const InstructionDesc& idesc = instruction_table.Get(current);
byte_size_operand_ = idesc.byte_size_operation;
switch (idesc.type) {
case ZERO_OPERANDS_INSTR:
if (current >= 0xA4 && current <= 0xA7) {
// String move or compare operations.
if (group_1_prefix_ == REP_PREFIX) {
// REP.
Print("rep ");
}
if ((current & 0x01) == 0x01) {
// Operation size: word, dword or qword
switch (operand_size()) {
case WORD_SIZE:
Print("%sw", idesc.mnem);
break;
case DOUBLEWORD_SIZE:
Print("%sl", idesc.mnem);
break;
case QUADWORD_SIZE:
Print("%sq", idesc.mnem);
break;
default:
UNREACHABLE();
}
} else {
// Operation size: byte
Print("%s", idesc.mnem);
}
} else if (current == 0x99 && rex_w()) {
Print("cqo"); // Cdql is called cdq and cdqq is called cqo.
} else {
Print("%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);
break;
case REGISTER_INSTR:
Print("%s%s %s", idesc.mnem, operand_size_code(),
NameOfCPURegister(base_reg(current & 0x07)));
(*data)++;
break;
case PUSHPOP_INSTR:
Print("%s %s", idesc.mnem, NameOfCPURegister(base_reg(current & 0x07)));
(*data)++;
break;
case MOVE_REG_INSTR: {
intptr_t addr = 0;
int imm_bytes = 0;
switch (operand_size()) {
case WORD_SIZE:
addr = LoadUnaligned(reinterpret_cast<int16_t*>(*data + 1));
imm_bytes = 2;
break;
case DOUBLEWORD_SIZE:
addr = LoadUnaligned(reinterpret_cast<int32_t*>(*data + 1));
imm_bytes = 4;
break;
case QUADWORD_SIZE:
addr = LoadUnaligned(reinterpret_cast<int64_t*>(*data + 1));
imm_bytes = 8;
break;
default:
UNREACHABLE();
}
(*data) += 1 + imm_bytes;
Print("mov%s %s,", operand_size_code(),
NameOfCPURegister(base_reg(current & 0x07)));
PrintImmediateValue(addr, /* signed = */ false, imm_bytes);
break;
}
case CALL_JUMP_INSTR: {
int32_t disp = LoadUnaligned(reinterpret_cast<int32_t*>(*data + 1)) + 5;
Print("%s ", idesc.mnem);
PrintJump(*data, disp);
(*data) += 5;
break;
}
case SHORT_IMMEDIATE_INSTR: {
Print("%s%s %s,", idesc.mnem, operand_size_code(), Rax());
PrintImmediate(*data + 1, DOUBLEWORD_SIZE);
(*data) += 5;
break;
}
case NO_INSTR:
return false;
default:
UNIMPLEMENTED(); // This type is not implemented.
}
return true;
}
int DisassemblerX64::Print660F38Instruction(uint8_t* current) {
int mod, regop, rm;
if (*current == 0x25) {
get_modrm(*(current + 1), &mod, &regop, &rm);
Print("pmovsxdq %s,", NameOfXMMRegister(regop));
return 1 + PrintRightXMMOperand(current + 1);
} else if (*current == 0x29) {
get_modrm(*(current + 1), &mod, &regop, &rm);
Print("pcmpeqq %s,", NameOfXMMRegister(regop));
return 1 + PrintRightXMMOperand(current + 1);
} else {
UnimplementedInstruction();
return 1;
}
}
// Handle all two-byte opcodes, which start with 0x0F.
// These instructions may be affected by an 0x66, 0xF2, or 0xF3 prefix.
// We do not use any three-byte opcodes, which start with 0x0F38 or 0x0F3A.
int DisassemblerX64::TwoByteOpcodeInstruction(uint8_t* data) {
uint8_t opcode = *(data + 1);
uint8_t* current = data + 2;
// At return, "current" points to the start of the next instruction.
const char* mnemonic = TwoByteMnemonic(opcode);
if (operand_size_ == 0x66) {
// 0x66 0x0F prefix.
int mod, regop, rm;
if (opcode == 0xC6) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("shufpd %s, ", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
Print(" [%x]", *current);
current++;
} else if (opcode == 0x3A) {
uint8_t third_byte = *current;
current = data + 3;
if (third_byte == 0x16) {
get_modrm(*current, &mod, &regop, &rm);
Print("pextrd "); // reg/m32, xmm, imm8
current += PrintRightOperand(current);
Print(",%s,%d", NameOfXMMRegister(regop), (*current) & 7);
current += 1;
} else if (third_byte == 0x17) {
get_modrm(*current, &mod, &regop, &rm);
Print("extractps "); // reg/m32, xmm, imm8
current += PrintRightOperand(current);
Print(", %s, %d", NameOfCPURegister(regop), (*current) & 3);
current += 1;
} else if (third_byte == 0x0b) {
get_modrm(*current, &mod, &regop, &rm);
// roundsd xmm, xmm/m64, imm8
Print("roundsd %s, ", NameOfCPURegister(regop));
current += PrintRightOperand(current);
Print(", %d", (*current) & 3);
current += 1;
} else {
UnimplementedInstruction();
}
} else {
get_modrm(*current, &mod, &regop, &rm);
if (opcode == 0x1f) {
current++;
if (rm == 4) { // SIB byte present.
current++;
}
if (mod == 1) { // Byte displacement.
current += 1;
} else if (mod == 2) { // 32-bit displacement.
current += 4;
} // else no immediate displacement.
Print("nop");
} else if (opcode == 0x28) {
Print("movapd %s, ", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0x29) {
Print("movapd ");
current += PrintRightXMMOperand(current);
Print(", %s", NameOfXMMRegister(regop));
} else if (opcode == 0x38) {
current += Print660F38Instruction(current);
} else if (opcode == 0x6E) {
Print("mov%c %s,", rex_w() ? 'q' : 'd', NameOfXMMRegister(regop));
current += PrintRightOperand(current);
} else if (opcode == 0x6F) {
Print("movdqa %s,", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0x7E) {
Print("mov%c ", rex_w() ? 'q' : 'd');
current += PrintRightOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else if (opcode == 0x7F) {
Print("movdqa ");
current += PrintRightXMMOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else if (opcode == 0xD6) {
Print("movq ");
current += PrintRightXMMOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else if (opcode == 0x50) {
Print("movmskpd %s,", NameOfCPURegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0xD7) {
Print("pmovmskb %s,", NameOfCPURegister(regop));
current += PrintRightXMMOperand(current);
} else {
const char* mnemonic = "?";
if (opcode == 0x5A) {
mnemonic = "cvtpd2ps";
} else if (0x51 <= opcode && opcode <= 0x5F) {
mnemonic = xmm_instructions[opcode & 0xF].pd_name;
} else if (opcode == 0x14) {
mnemonic = "unpcklpd";
} else if (opcode == 0x15) {
mnemonic = "unpckhpd";
} else if (opcode == 0x2E) {
mnemonic = "ucomisd";
} else if (opcode == 0x2F) {
mnemonic = "comisd";
} else if (opcode == 0xFE) {
mnemonic = "paddd";
} else if (opcode == 0xFA) {
mnemonic = "psubd";
} else if (opcode == 0xEF) {
mnemonic = "pxor";
} else {
UnimplementedInstruction();
}
Print("%s %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
}
}
} else if (group_1_prefix_ == 0xF2) {
// Beginning of instructions with prefix 0xF2.
if (opcode == 0x11 || opcode == 0x10) {
// MOVSD: Move scalar double-precision fp to/from/between XMM registers.
Print("movsd ");
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
if (opcode == 0x11) {
current += PrintRightXMMOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else {
Print("%s,", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
}
} else if (opcode == 0x2A) {
// CVTSI2SD: integer to XMM double conversion.
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("%sd %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightOperand(current);
} else if (opcode == 0x2C) {
// CVTTSD2SI:
// Convert with truncation scalar double-precision FP to integer.
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("cvttsd2si%s %s,", operand_size_code(), NameOfCPURegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0x2D) {
// CVTSD2SI: Convert scalar double-precision FP to integer.
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("cvtsd2si%s %s,", operand_size_code(), NameOfCPURegister(regop));
current += PrintRightXMMOperand(current);
} else if (0x51 <= opcode && opcode <= 0x5F) {
// XMM arithmetic. Get the F2 0F prefix version of the mnemonic.
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
const char* mnemonic =
opcode == 0x5A ? "cvtsd2ss" : xmm_instructions[opcode & 0xF].sd_name;
Print("%s %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else {
UnimplementedInstruction();
}
} else if (group_1_prefix_ == 0xF3) {
// Instructions with prefix 0xF3.
if (opcode == 0x11 || opcode == 0x10) {
// MOVSS: Move scalar double-precision fp to/from/between XMM registers.
Print("movss ");
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
if (opcode == 0x11) {
current += PrintRightOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else {
Print("%s,", NameOfXMMRegister(regop));
current += PrintRightOperand(current);
}
} else if (opcode == 0x2A) {
// CVTSI2SS: integer to XMM single conversion.
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("%ss %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightOperand(current);
} else if (opcode == 0x2C || opcode == 0x2D) {
bool truncating = (opcode & 1) == 0;
// CVTTSS2SI/CVTSS2SI:
// Convert (with truncation) scalar single-precision FP to dword integer.
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("cvt%sss2si%s %s,", truncating ? "t" : "", operand_size_code(),
NameOfCPURegister(regop));
current += PrintRightXMMOperand(current);
} else if (0x51 <= opcode && opcode <= 0x5F) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
const char* mnemonic =
opcode == 0x5A ? "cvtss2sd" : xmm_instructions[opcode & 0xF].ss_name;
Print("%s %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0x7E) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("movq %s, ", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0xE6) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("cvtdq2pd %s,", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0xB8) {
// POPCNT.
current += PrintOperands(mnemonic, REG_OPER_OP_ORDER, current);
} else if (opcode == 0xBD) {
// LZCNT (rep BSR encoding).
current += PrintOperands("lzcnt", REG_OPER_OP_ORDER, current);
} else {
UnimplementedInstruction();
}
} else if (opcode == 0x1F) {
// NOP
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
current++;
if (rm == 4) { // SIB byte present.
current++;
}
if (mod == 1) { // Byte displacement.
current += 1;
} else if (mod == 2) { // 32-bit displacement.
current += 4;
} // else no immediate displacement.
Print("nop");
} else if (opcode == 0x28 || opcode == 0x2f) {
// ...s xmm, xmm/m128
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
const char* mnemonic = opcode == 0x28 ? "movaps" : "comiss";
Print("%s %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0x29) {
// movaps xmm/m128, xmm
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("movaps ");
current += PrintRightXMMOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else if (opcode == 0x11) {
// movups xmm/m128, xmm
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("movups ");
current += PrintRightXMMOperand(current);
Print(",%s", NameOfXMMRegister(regop));
} else if (opcode == 0x50) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("movmskps %s,", NameOfCPURegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0xA2 || opcode == 0x31) {
// RDTSC or CPUID
Print("%s", mnemonic);
} else if ((opcode & 0xF0) == 0x40) {
// CMOVcc: conditional move.
int condition = opcode & 0x0F;
const InstructionDesc& idesc = cmov_instructions[condition];
byte_size_operand_ = idesc.byte_size_operation;
current += PrintOperands(idesc.mnem, idesc.op_order_, current);
} else if (0x10 <= opcode && opcode <= 0x16) {
// ...ps xmm, xmm/m128
static const char* const mnemonics[] = {
"movups", NULL, "movhlps", NULL, "unpcklps", "unpckhps", "movlhps"};
const char* mnemonic = mnemonics[opcode - 0x10];
if (mnemonic == NULL) {
UnimplementedInstruction();
mnemonic = "???";
}
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
Print("%s %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (0x51 <= opcode && opcode <= 0x5F) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
const char* mnemonic =
opcode == 0x5A ? "cvtps2pd" : xmm_instructions[opcode & 0xF].ps_name;
Print("%s %s,", mnemonic, NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
} else if (opcode == 0xC2 || opcode == 0xC6) {
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
if (opcode == 0xC2) {
Print("cmpps %s,", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
Print(" [%s]", xmm_conditional_code_suffix[*current]);
} else {
ASSERT(opcode == 0xC6);
Print("shufps %s,", NameOfXMMRegister(regop));
current += PrintRightXMMOperand(current);
Print(" [%x]", *current);
}
current++;
} else if ((opcode & 0xF0) == 0x80) {
// Jcc: Conditional jump (branch).
current = data + JumpConditional(data);
} else if (opcode == 0xBE || opcode == 0xBF || opcode == 0xB6 ||
opcode == 0xB7 || opcode == 0xAF || opcode == 0xB0 ||
opcode == 0xB1 || opcode == 0xBC || opcode == 0xBD) {
// Size-extending moves, IMUL, cmpxchg, BSF, BSR.
current += PrintOperands(mnemonic, REG_OPER_OP_ORDER, current);
} else if ((opcode & 0xF0) == 0x90) {
// SETcc: Set byte on condition. Needs pointer to beginning of instruction.
current = data + SetCC(data);
} else if (((opcode & 0xFE) == 0xA4) || ((opcode & 0xFE) == 0xAC) ||
(opcode == 0xAB) || (opcode == 0xA3)) {
// SHLD, SHRD (double-prec. shift), BTS (bit test and set), BT (bit test).
Print("%s%s ", mnemonic, operand_size_code());
int mod, regop, rm;
get_modrm(*current, &mod, &regop, &rm);
current += PrintRightOperand(current);
Print(",%s", NameOfCPURegister(regop));
if ((opcode == 0xAB) || (opcode == 0xA3) || (opcode == 0xBD)) {
// Done.
} else if ((opcode == 0xA5) || (opcode == 0xAD)) {
Print(",cl");
} else {
Print(",");
current += PrintImmediate(current, BYTE_SIZE);
}
} else if (opcode == 0xBA && (*current & 0x60) == 0x60) {
// bt? immediate instruction
int r = (*current >> 3) & 7;
static const char* const names[4] = {"bt", "bts", "btr", "btc"};
Print("%s ", names[r - 4]);
current += PrintRightOperand(current);
uint8_t bit = *current++;
Print(",%d", bit);
} else {
UnimplementedInstruction();
}
return static_cast<int>(current - data);
}
// Mnemonics for two-byte opcode instructions starting with 0x0F.
// The argument is the second byte of the two-byte opcode.
// Returns NULL if the instruction is not handled here.
const char* DisassemblerX64::TwoByteMnemonic(uint8_t opcode) {
if (opcode == 0x5A) {
return "cvtps2pd";
} else if (0x51 <= opcode && opcode <= 0x5F) {
return xmm_instructions[opcode & 0xF].ps_name;
}
if (0xA2 <= opcode && opcode <= 0xBF) {
static const char* const mnemonics[] = {
"cpuid", "bt", "shld", "shld", NULL, NULL,
NULL, NULL, NULL, "bts", "shrd", "shrd",
NULL, "imul", "cmpxchg", "cmpxchg", NULL, NULL,
NULL, NULL, "movzxb", "movzxw", "popcnt", NULL,
NULL, NULL, "bsf", "bsr", "movsxb", "movsxw"};
return mnemonics[opcode - 0xA2];
}
switch (opcode) {
case 0x12:
return "movhlps";
case 0x16:
return "movlhps";
case 0x1F:
return "nop";
case 0x2A: // F2/F3 prefix.
return "cvtsi2s";
case 0x31:
return "rdtsc";
default:
return NULL;
}
}
int DisassemblerX64::InstructionDecode(uword pc) {
uint8_t* data = reinterpret_cast<uint8_t*>(pc);
const bool processed = DecodeInstructionType(&data);
if (!processed) {
switch (*data) {
case 0xC2:
Print("ret ");
PrintImmediateValue(*reinterpret_cast<uint16_t*>(data + 1));
data += 3;
break;
case 0xC8:
Print("enter %d, %d", *reinterpret_cast<uint16_t*>(data + 1), data[3]);
data += 4;
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)
: LoadUnaligned(reinterpret_cast<int32_t*>(data + 2));
Print("imul%s %s,%s,", operand_size_code(), NameOfCPURegister(regop),
NameOfCPURegister(rm));
PrintImmediateValue(imm);
data += 2 + (*data == 0x6B ? 1 : 4);
break;
}
case 0x81:
FALL_THROUGH;
case 0x83: // 0x81 with sign extension bit set
data += PrintImmediateOp(data);
break;
case 0x0F:
data += TwoByteOpcodeInstruction(data);
break;
case 0x8F: {
data++;
int mod, regop, rm;
get_modrm(*data, &mod, &regop, &rm);
if (regop == 0) {
Print("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 0:
mnem = "inc";
break;
case 1:
mnem = "dec";
break;
case 2:
mnem = "call";
break;
case 4:
mnem = "jmp";
break;
case 6:
mnem = "push";
break;
default:
mnem = "???";
}
if (regop <= 1) {
Print("%s%s ", mnem, operand_size_code());
} else {
Print("%s ", mnem);
}
data += PrintRightOperand(data);
} break;
case 0xC7: // imm32, fall through
case 0xC6: // imm8
{
bool is_byte = *data == 0xC6;
data++;
if (is_byte) {
Print("movb ");
data += PrintRightByteOperand(data);
Print(",");
data += PrintImmediate(data, BYTE_SIZE);
} else {
Print("mov%s ", operand_size_code());
data += PrintRightOperand(data);
Print(",");
data +=
PrintImmediate(data, operand_size(), /* sign extend = */ true);
}
} break;
case 0x80: {
byte_size_operand_ = true;
data += PrintImmediateOp(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) {
Print("movb ");
data += PrintRightByteOperand(data);
Print(",%s", NameOfByteCPURegister(regop));
} else {
Print("mov%s ", operand_size_code());
data += PrintRightOperand(data);
Print(",%s", NameOfCPURegister(regop));
}
} break;
case 0x90:
case 0x91:
case 0x92:
case 0x93:
case 0x94:
case 0x95:
case 0x96:
case 0x97: {
int reg = (*data & 0x7) | (rex_b() ? 8 : 0);
if (reg == 0) {
Print("nop"); // Common name for xchg rax,rax.
} else {
Print("xchg%s %s, %s", operand_size_code(), Rax(),
NameOfCPURegister(reg));
}
data++;
} break;
case 0xB0:
case 0xB1:
case 0xB2:
case 0xB3:
case 0xB4:
case 0xB5:
case 0xB6:
case 0xB7:
case 0xB8:
case 0xB9:
case 0xBA:
case 0xBB:
case 0xBC:
case 0xBD:
case 0xBE:
case 0xBF: {
// mov reg8,imm8 or mov reg32,imm32
uint8_t opcode = *data;
data++;
const bool is_not_8bit = opcode >= 0xB8;
int reg = (opcode & 0x7) | (rex_b() ? 8 : 0);
if (is_not_8bit) {
Print("mov%s %s,", operand_size_code(), NameOfCPURegister(reg));
data +=
PrintImmediate(data, operand_size(), /* sign extend = */ false);
} else {
Print("movb %s,", NameOfByteCPURegister(reg));
data += PrintImmediate(data, BYTE_SIZE, /* sign extend = */ false);
}
break;
}
case 0xFE: {
data++;
int mod, regop, rm;
get_modrm(*data, &mod, &regop, &rm);
if (regop == 1) {
Print("decb ");
data += PrintRightByteOperand(data);
} else {
UnimplementedInstruction();
}
break;
}
case 0x68:
Print("push ");
PrintImmediateValue(
LoadUnaligned(reinterpret_cast<int32_t*>(data + 1)));
data += 5;
break;
case 0x6A:
Print("push ");
PrintImmediateValue(*reinterpret_cast<int8_t*>(data + 1));
data += 2;
break;
case 0xA1:
FALL_THROUGH;
case 0xA3:
switch (operand_size()) {
case DOUBLEWORD_SIZE: {
PrintAddress(reinterpret_cast<uint8_t*>(
*reinterpret_cast<int32_t*>(data + 1)));
if (*data == 0xA1) { // Opcode 0xA1
Print("movzxlq %s,(", Rax());
PrintAddress(reinterpret_cast<uint8_t*>(
*reinterpret_cast<int32_t*>(data + 1)));
Print(")");
} else { // Opcode 0xA3
Print("movzxlq (");
PrintAddress(reinterpret_cast<uint8_t*>(
*reinterpret_cast<int32_t*>(data + 1)));
Print("),%s", Rax());
}
data += 5;
break;
}
case QUADWORD_SIZE: {
// New x64 instruction mov rax,(imm_64).
if (*data == 0xA1) { // Opcode 0xA1
Print("movq %s,(", Rax());
PrintAddress(*reinterpret_cast<uint8_t**>(data + 1));
Print(")");
} else { // Opcode 0xA3
Print("movq (");
PrintAddress(*reinterpret_cast<uint8_t**>(data + 1));
Print("),%s", Rax());
}
data += 9;
break;
}
default:
UnimplementedInstruction();
data += 2;
}
break;
case 0xA8:
Print("test al,");
PrintImmediateValue(*reinterpret_cast<uint8_t*>(data + 1));
data += 2;
break;
case 0xA9: {
data++;
Print("test%s %s,", operand_size_code(), Rax());
data += PrintImmediate(data, operand_size());
break;
}
case 0xD1:
FALL_THROUGH;
case 0xD3:
FALL_THROUGH;
case 0xC1:
data += ShiftInstruction(data);
break;
case 0xD0:
FALL_THROUGH;
case 0xD2:
FALL_THROUGH;
case 0xC0:
byte_size_operand_ = true;
data += ShiftInstruction(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 0xF6:
byte_size_operand_ = true;
FALL_THROUGH;
case 0xF7:
data += F6F7Instruction(data);
break;
// These encodings for inc and dec are IA32 only, but we don't get here
// on X64 - the REX prefix recoginizer catches them earlier.
case 0x40:
case 0x41:
case 0x42:
case 0x43:
case 0x44:
case 0x45:
case 0x46:
case 0x47:
Print("inc %s", NameOfCPURegister(*data & 7));
data += 1;
break;
case 0x48:
case 0x49:
case 0x4a:
case 0x4b:
case 0x4c:
case 0x4d:
case 0x4e:
case 0x4f:
Print("dec %s", NameOfCPURegister(*data & 7));
data += 1;
break;
#if defined(TARGET_ARCH_IA32)
case 0x61:
Print("popad");
break;
case 0x60:
Print("pushad");
break;
#endif
default:
UnimplementedInstruction();
data += 1;
}
} // !processed
ASSERT(buffer_[buffer_pos_] == '\0');
int instr_len = data - reinterpret_cast<uint8_t*>(pc);
ASSERT(instr_len > 0); // Ensure progress.
return instr_len;
}
void Disassembler::DecodeInstruction(char* hex_buffer,
intptr_t hex_size,
char* human_buffer,
intptr_t human_size,
int* out_instr_len,
const Code& code,
Object** object,
uword pc) {
ASSERT(hex_size > 0);
ASSERT(human_size > 0);
DisassemblerX64 decoder(human_buffer, human_size);
int instruction_length = decoder.InstructionDecode(pc);
uint8_t* pc_ptr = reinterpret_cast<uint8_t*>(pc);
int hex_index = 0;
int remaining_size = hex_size - hex_index;
for (int i = 0; (i < instruction_length) && (remaining_size > 2); ++i) {
Utils::SNPrint(&hex_buffer[hex_index], remaining_size, "%02x", pc_ptr[i]);
hex_index += 2;
remaining_size -= 2;
}
hex_buffer[hex_index] = '\0';
if (out_instr_len != nullptr) {
*out_instr_len = instruction_length;
}
*object = NULL;
#if defined(TARGET_ARCH_X64)
if (!code.IsNull()) {
*object = &Object::Handle();
if (!DecodeLoadObjectFromPoolOrThread(pc, code, *object)) {
*object = NULL;
}
}
#else
if (!code.IsNull() && code.is_alive()) {
intptr_t offsets_length = code.pointer_offsets_length();
for (intptr_t i = 0; i < offsets_length; i++) {
uword addr = code.GetPointerOffsetAt(i) + code.PayloadStart();
if ((pc <= addr) && (addr < (pc + instruction_length))) {
*object =
&Object::Handle(LoadUnaligned(reinterpret_cast<ObjectPtr*>(addr)));
break;
}
}
}
#endif
}
#endif // !defined(PRODUCT) || defined(FORCE_INCLUDE_DISASSEMBLER)
} // namespace dart
#endif // defined(TARGET_ARCH_X64) || defined (TARGET_ARCH_IA32)