diff options
-rw-r--r-- | disassembler/disassembler_x86.cc | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/disassembler/disassembler_x86.cc b/disassembler/disassembler_x86.cc index e6a6860..b012bc1 100644 --- a/disassembler/disassembler_x86.cc +++ b/disassembler/disassembler_x86.cc @@ -56,10 +56,16 @@ static const char* gReg64Names[] = { "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15" }; +// 64-bit opcode REX modifier. +constexpr uint8_t REX_W = 0b1000; +constexpr uint8_t REX_R = 0b0100; +constexpr uint8_t REX_X = 0b0010; +constexpr uint8_t REX_B = 0b0001; + static void DumpReg0(std::ostream& os, uint8_t rex, size_t reg, bool byte_operand, uint8_t size_override) { DCHECK_LT(reg, (rex == 0) ? 8u : 16u); - bool rex_w = (rex & 0b1000) != 0; + bool rex_w = (rex & REX_W) != 0; if (byte_operand) { os << ((rex == 0) ? gReg8Names[reg] : gExtReg8Names[reg]); } else if (rex_w) { @@ -86,14 +92,14 @@ static void DumpAnyReg(std::ostream& os, uint8_t rex, size_t reg, static void DumpReg(std::ostream& os, uint8_t rex, uint8_t reg, bool byte_operand, uint8_t size_override, RegFile reg_file) { - bool rex_r = (rex & 0b0100) != 0; + bool rex_r = (rex & REX_R) != 0; size_t reg_num = rex_r ? (reg + 8) : reg; DumpAnyReg(os, rex, reg_num, byte_operand, size_override, reg_file); } static void DumpRmReg(std::ostream& os, uint8_t rex, uint8_t reg, bool byte_operand, uint8_t size_override, RegFile reg_file) { - bool rex_b = (rex & 0b0001) != 0; + bool rex_b = (rex & REX_B) != 0; size_t reg_num = rex_b ? (reg + 8) : reg; DumpAnyReg(os, rex, reg_num, byte_operand, size_override, reg_file); } @@ -107,19 +113,19 @@ static void DumpAddrReg(std::ostream& os, uint8_t rex, uint8_t reg) { } static void DumpBaseReg(std::ostream& os, uint8_t rex, uint8_t reg) { - bool rex_b = (rex & 0b0001) != 0; + bool rex_b = (rex & REX_B) != 0; size_t reg_num = rex_b ? (reg + 8) : reg; DumpAddrReg(os, rex, reg_num); } static void DumpIndexReg(std::ostream& os, uint8_t rex, uint8_t reg) { - bool rex_x = (rex & 0b0010) != 0; + bool rex_x = (rex & REX_X) != 0; uint8_t reg_num = rex_x ? (reg + 8) : reg; DumpAddrReg(os, rex, reg_num); } static void DumpOpcodeReg(std::ostream& os, uint8_t rex, uint8_t reg) { - bool rex_b = (rex & 0b0001) != 0; + bool rex_b = (rex & REX_B) != 0; size_t reg_num = rex_b ? (reg + 8) : reg; DumpReg0(os, rex, reg_num, false, 0); } @@ -896,6 +902,7 @@ DISASSEMBLER_ENTRY(cmp, case 0xB0: case 0xB1: case 0xB2: case 0xB3: case 0xB4: case 0xB5: case 0xB6: case 0xB7: opcode << "mov"; immediate_bytes = 1; + byte_operand = true; reg_in_opcode = true; break; case 0xB8: case 0xB9: case 0xBA: case 0xBB: case 0xBC: case 0xBD: case 0xBE: case 0xBF: @@ -916,6 +923,15 @@ DISASSEMBLER_ENTRY(cmp, byte_operand = (*instr == 0xC0); break; case 0xC3: opcode << "ret"; break; + case 0xC6: + static const char* c6_opcodes[] = {"mov", "unknown-c6", "unknown-c6", "unknown-c6", "unknown-c6", "unknown-c6", "unknown-c6", "unknown-c6"}; + modrm_opcodes = c6_opcodes; + store = true; + immediate_bytes = 1; + has_modrm = true; + reg_is_opcode = true; + byte_operand = true; + break; case 0xC7: static const char* c7_opcodes[] = {"mov", "unknown-c7", "unknown-c7", "unknown-c7", "unknown-c7", "unknown-c7", "unknown-c7", "unknown-c7"}; modrm_opcodes = c7_opcodes; @@ -1064,6 +1080,16 @@ DISASSEMBLER_ENTRY(cmp, if (reg_is_opcode && modrm_opcodes != NULL) { opcode << modrm_opcodes[reg_or_opcode]; } + + // Add opcode suffixes to indicate size. + if (byte_operand) { + opcode << 'b'; + } else if ((rex & REX_W) != 0) { + opcode << 'q'; + } else if (prefix[2] == 0x66) { + opcode << 'w'; + } + if (load) { if (!reg_is_opcode) { DumpReg(args, rex, reg_or_opcode, byte_operand, prefix[2], dst_reg_file); |