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-rw-r--r--src/lib.rs2040
1 files changed, 2040 insertions, 0 deletions
diff --git a/src/lib.rs b/src/lib.rs
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index 0000000..3ba62fa
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,2040 @@
+use std::fs::File;
+use std::io::Read;
+
+//use std;
+use std::fmt;
+
+use std::hint::unreachable_unchecked;
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub struct RegSpec {
+ num: u8,
+ bank: RegisterBank
+}
+
+impl fmt::Display for RegSpec {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ let name = match self.bank {
+ RegisterBank::Q => {
+ ["rax", "rcx", "rdx", "rbx", "rsp", "rbp", "rsi", "rdi", "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"][self.num as usize]
+ },
+ RegisterBank::D => {
+ ["eax", "ecx", "edx", "ebx", "esp", "ebp", "esi", "edi", "r8d", "r9d", "r10d", "r11d", "r12d", "r13d", "r14d", "r15d"][self.num as usize]
+ },
+ RegisterBank::W => {
+ ["ax", "cx", "dx", "bx", "sp", "bp", "si", "di", "r8w", "r9w", "r10w", "r11w", "r12w", "r13w", "r14w", "r15w"][self.num as usize]
+ },
+ RegisterBank::B => {
+ ["al", "cl", "dl", "bl", "ah", "ch", "dh", "bh"][self.num as usize]
+ },
+ RegisterBank::rB => {
+ ["al", "cl", "dl", "bl", "spl", "bpl", "sil", "dil"][self.num as usize]
+ },
+ RegisterBank::EIP => { "eip" },
+ RegisterBank::RIP => { "rip" },
+ _ => panic!("unnamable register")
+ };
+ write!(f, "{}", name)
+ }
+}
+
+enum SizeCode {
+ b,
+ vd,
+ vq,
+ vqp
+}
+
+impl fmt::Display for Operand {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ match self {
+ &Operand::ImmediateI16(imm) => write!(f, "0x{:x}", imm),
+ &Operand::ImmediateU16(imm) => write!(f, "0x{:x}", imm),
+ &Operand::ImmediateU32(imm) => write!(f, "0x{:x}", imm),
+ &Operand::ImmediateI32(imm) => write!(f, "0x{:x}", imm),
+ &Operand::ImmediateU64(imm) => write!(f, "0x{:x}", imm),
+ &Operand::ImmediateI64(imm) => write!(f, "0x{:x}", imm),
+ &Operand::Register(ref spec) => write!(f, "{}", spec),
+ &Operand::ImmediateI8(imm) => write!(f, "0x{:x}", imm),
+ &Operand::ImmediateU8(imm) => write!(f, "0x{:x}", imm),
+ &Operand::DisplacementU32(imm) => write!(f, "[0x{:x}]", imm),
+ &Operand::DisplacementI32(imm) => write!(f, "[0x{:x}]", imm),
+ &Operand::RegDisp(ref spec, ref disp) => write!(f, "[{} + 0x{:x}]",
+ spec, disp),
+ &Operand::RegDeref(ref spec) => write!(f, "[{}]", spec),
+ &Operand::RegScale(ref spec, scale) => write!(f, "[{} * {}]", spec, scale),
+ &Operand::RegScaleDisp(ref spec, scale, disp) => {
+ write!(f, "[{} * {} + 0x{:x}]", spec, scale, disp)
+ },
+ &Operand::RegIndexBase(ref base, ref index) => {
+ write!(f, "[{} + {}]", base, index)
+ }
+ &Operand::RegIndexBaseDisp(ref base, ref index, disp) => {
+ write!(f, "[{} + {} + 0x{:x}]", base, index, disp)
+ },
+ &Operand::RegIndexBaseScale(ref base, ref index, scale) => {
+ write!(f, "[{} + {} * {}]", base, index, scale)
+ }
+ &Operand::RegIndexBaseScaleDisp(ref base, ref index, scale, disp) => {
+ write!(f, "[{} + {} * {} + 0x{:x}]", base, index, scale, disp)
+ },
+ &Operand::Nothing => { Ok(()) },
+ &Operand::Many(_) => { panic!("many not covered"); }
+ }
+ }
+}
+
+#[derive(Clone, Debug)]
+pub enum Operand {
+ ImmediateI8(i8),
+ ImmediateU8(u8),
+ ImmediateI16(i16),
+ ImmediateU16(u16),
+ ImmediateU32(u32),
+ ImmediateI32(i32),
+ ImmediateU64(u64),
+ ImmediateI64(i64),
+ Register(RegSpec),
+ DisplacementI32(u32),
+ DisplacementU32(i32),
+ RegDeref(RegSpec),
+ RegDisp(RegSpec, i32),
+ RegScale(RegSpec, u8),
+ RegIndexBase(RegSpec, RegSpec),
+ RegIndexBaseDisp(RegSpec, RegSpec, i32),
+ RegScaleDisp(RegSpec, u8, i32),
+ RegIndexBaseScale(RegSpec, RegSpec, u8),
+ RegIndexBaseScaleDisp(RegSpec, RegSpec, u8, i32),
+ Many(Vec<Operand>),
+ Nothing
+}
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub enum RegisterBank {
+ Q, D, W, B, rB, // Quadword, Dword, Word, Byte
+ CR, DR, S, EIP, RIP, // Control reg, Debug reg, Selector, ...
+ X, Y, Z, // XMM, YMM, ZMM
+ ST, MM, // ST, MM regs (x87, mmx)
+}
+
+#[derive(Debug)]
+pub enum Segment {
+ CS, DS, ES, FS, GS, SS
+}
+
+impl fmt::Display for Opcode {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ match self {
+ &Opcode::INC => write!(f, "{}", "inc"),
+ &Opcode::DEC => write!(f, "{}", "dec"),
+ &Opcode::HLT => write!(f, "{}", "hlt"),
+ &Opcode::SBB => write!(f, "{}", "sbb"),
+ &Opcode::AND => write!(f, "{}", "and"),
+ &Opcode::XOR => write!(f, "{}", "xor"),
+ &Opcode::OR => write!(f, "{}", "or"),
+ &Opcode::PUSH => write!(f, "{}", "push"),
+ &Opcode::POP => write!(f, "{}", "pop"),
+ &Opcode::LEA => write!(f, "{}", "lea"),
+ &Opcode::NOP => write!(f, "{}", "nop"),
+ &Opcode::XCHG => write!(f, "{}", "xchg"),
+ &Opcode::POPF => write!(f, "{}", "popf"),
+ &Opcode::ADD => write!(f, "{}", "add"),
+ &Opcode::ADC => write!(f, "{}", "adc"),
+ &Opcode::SUB => write!(f, "{}", "sub"),
+ &Opcode::INT => write!(f, "{}", "int"),
+ &Opcode::INTO => write!(f, "{}", "into"),
+ &Opcode::IRET => write!(f, "{}", "iret"),
+ &Opcode::RETF => write!(f, "{}", "retf"),
+ &Opcode::ENTER => write!(f, "{}", "enter"),
+ &Opcode::LEAVE => write!(f, "{}", "leave"),
+ &Opcode::MOV => write!(f, "{}", "mov"),
+ &Opcode::RETURN => write!(f, "{}", "ret"),
+ &Opcode::PUSHF => write!(f, "{}", "pushf"),
+ &Opcode::WAIT => write!(f, "{}", "wait"),
+ &Opcode::CBW => write!(f, "{}", "cbw"),
+ &Opcode::CDW => write!(f, "{}", "cdw"),
+ &Opcode::LODS => write!(f, "{}", "lods"),
+ &Opcode::STOS => write!(f, "{}", "stos"),
+ &Opcode::LAHF => write!(f, "{}", "lahf"),
+ &Opcode::SAHF => write!(f, "{}", "sahf"),
+ &Opcode::CMPS => write!(f, "{}", "cmps"),
+ &Opcode::SCAS => write!(f, "{}", "scas"),
+ &Opcode::MOVS => write!(f, "{}", "movs"),
+ &Opcode::TEST => write!(f, "{}", "test"),
+ &Opcode::CMP => write!(f, "{}", "cmp"),
+ &Opcode::INS => write!(f, "{}", "ins"),
+ &Opcode::OUTS => write!(f, "{}", "outs"),
+ &Opcode::IMUL => write!(f, "{}", "imul"),
+ &Opcode::JO => write!(f, "{}", "jo"),
+ &Opcode::JNO => write!(f, "{}", "jno"),
+ &Opcode::JB => write!(f, "{}", "jb"),
+ &Opcode::JNB => write!(f, "{}", "jnb"),
+ &Opcode::JZ => write!(f, "{}", "jz"),
+ &Opcode::JNZ => write!(f, "{}", "jnz"),
+ &Opcode::JA => write!(f, "{}", "ja"),
+ &Opcode::JNA => write!(f, "{}", "jna"),
+ &Opcode::JS => write!(f, "{}", "js"),
+ &Opcode::JNS => write!(f, "{}", "jns"),
+ &Opcode::JP => write!(f, "{}", "jp"),
+ &Opcode::JNP => write!(f, "{}", "jnp"),
+ &Opcode::JL => write!(f, "{}", "jl"),
+ &Opcode::JGE => write!(f, "{}", "jge"),
+ &Opcode::JLE => write!(f, "{}", "jle"),
+ &Opcode::JG => write!(f, "{}", "jg"),
+ &Opcode::CALL => write!(f, "{}", "call"),
+ &Opcode::JMP => write!(f, "{}", "jmp"),
+ &Opcode::CALLF => write!(f, "{}", "callf"),
+ &Opcode::JMPF => write!(f, "{}", "jmpf"),
+ &Opcode::SAR => write!(f, "{}", "sar"),
+ &Opcode::SAL => write!(f, "{}", "sal"),
+ &Opcode::SHR => write!(f, "{}", "shr"),
+ &Opcode::SHL => write!(f, "{}", "shl"),
+ &Opcode::RCR => write!(f, "{}", "rcr"),
+ &Opcode::RCL => write!(f, "{}", "rcl"),
+ &Opcode::ROR => write!(f, "{}", "ror"),
+ &Opcode::ROL => write!(f, "{}", "rol"),
+ &Opcode::CMOVA => write!(f, "{}", "cmova"),
+ &Opcode::CMOVB => write!(f, "{}", "cmovb"),
+ &Opcode::CMOVG => write!(f, "{}", "cmovg"),
+ &Opcode::CMOVGE => write!(f, "{}", "cmovge"),
+ &Opcode::CMOVL => write!(f, "{}", "cmovl"),
+ &Opcode::CMOVLE => write!(f, "{}", "cmovle"),
+ &Opcode::CMOVNA => write!(f, "{}", "cmovna"),
+ &Opcode::CMOVNB => write!(f, "{}", "cmovnb"),
+ &Opcode::CMOVNO => write!(f, "{}", "cmovno"),
+ &Opcode::CMOVNP => write!(f, "{}", "cmovnp"),
+ &Opcode::CMOVNS => write!(f, "{}", "cmovns"),
+ &Opcode::CMOVNZ => write!(f, "{}", "cmovnz"),
+ &Opcode::CMOVO => write!(f, "{}", "cmovo"),
+ &Opcode::CMOVP => write!(f, "{}", "cmovp"),
+ &Opcode::CMOVS => write!(f, "{}", "cmovs"),
+ &Opcode::CMOVZ => write!(f, "{}", "cmovz"),
+ &Opcode::NEG => write!(f, "{}", "neg"),
+ &Opcode::NOT => write!(f, "{}", "not"),
+ &Opcode::MUL => write!(f, "{}", "mul"),
+ &Opcode::IMUL => write!(f, "{}", "imul"),
+ &Opcode::DIV => write!(f, "{}", "div"),
+ &Opcode::IDIV => write!(f, "{}", "idiv"),
+ &Opcode::CMPXCHG => write!(f, "{}", "cmpxchg"),
+ &Opcode::Invalid => write!(f, "{}", "invalid")
+ }
+ }
+}
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub enum Opcode {
+ SAR,
+ SAL,
+ SHR,
+ SHL,
+ RCR,
+ RCL,
+ ROR,
+ ROL,
+ INC,
+ DEC,
+ HLT,
+ CALL,
+ CALLF,
+ JMP,
+ JMPF,
+ SBB,
+ AND,
+ XOR,
+ OR,
+ PUSH,
+ POP,
+ LEA,
+ NOP,
+ XCHG,
+ POPF,
+ ADD,
+ ADC,
+ SUB,
+ INT,
+ INTO,
+ IRET,
+ RETF,
+ ENTER,
+ LEAVE,
+ MOV,
+ RETURN,
+ PUSHF,
+ WAIT,
+ CBW,
+ CDW,
+ LODS,
+ STOS,
+ LAHF,
+ SAHF,
+ CMPS,
+ SCAS,
+ MOVS,
+ TEST,
+ CMP,
+ INS,
+ OUTS,
+ IMUL,
+ JO,
+ JNO,
+ JB,
+ JNB,
+ JZ,
+ JNZ,
+ JA,
+ JNA,
+ JS,
+ JNS,
+ JP,
+ JNP,
+ JL,
+ JGE,
+ JLE,
+ JG,
+ CMOVA,
+ CMOVB,
+ CMOVG,
+ CMOVGE,
+ CMOVL,
+ CMOVLE,
+ CMOVNA,
+ CMOVNB,
+ CMOVNO,
+ CMOVNP,
+ CMOVNS,
+ CMOVNZ,
+ CMOVO,
+ CMOVP,
+ CMOVS,
+ CMOVZ,
+ DIV,
+ IDIV,
+ MUL,
+ NEG,
+ NOT,
+ CMPXCHG,
+ Invalid
+}
+#[derive(Debug)]
+pub struct Instruction {
+ pub prefixes: Prefixes,
+ pub opcode: Opcode,
+ pub operands: [Operand; 2]
+}
+
+impl Instruction {
+ pub fn invalid() -> Instruction {
+ Instruction {
+ prefixes: Prefixes::new(0),
+ opcode: Opcode::Invalid,
+ operands: [Operand::Nothing, Operand::Nothing]
+ }
+ }
+ pub fn is_invalid(&self) -> bool {
+ match self.opcode {
+ Opcode::Invalid => true,
+ _ => false
+ }
+ }
+}
+
+#[derive(Debug)]
+pub struct Prefixes {
+ bits: u8,
+ rex: PrefixRex,
+ segment: Segment,
+ lock: bool
+}
+
+#[derive(Debug)]
+pub struct PrefixRex {
+ bits: u8
+}
+
+impl Prefixes {
+ fn new(bits: u8) -> Prefixes {
+ Prefixes {
+ bits: bits,
+ rex: PrefixRex { bits: 0 },
+ segment: Segment::DS,
+ lock: false
+ }
+ }
+ fn rep(&self) -> bool { self.bits & 0x30 == 0x10 }
+ fn set_rep(&mut self) { self.bits = (self.bits & 0xcf) | 0x10 }
+ fn repz(&self) -> bool { self.bits & 0x30 == 0x20 }
+ fn set_repz(&mut self) { self.bits = (self.bits & 0xcf) | 0x20 }
+ fn repnz(&self) -> bool { self.bits & 0x30 == 0x30 }
+ fn set_repnz(&mut self) { self.bits = (self.bits & 0xcf) | 0x30 }
+ fn lock(&self) -> bool { self.lock }
+ fn set_lock(&mut self) { self.lock = true; }
+ fn operand_size(&self) -> bool { self.bits & 0x1 == 1 }
+ fn set_operand_size(&mut self) { self.bits = self.bits | 0x1 }
+ fn address_size(&self) -> bool { self.bits & 0x2 == 2 }
+ fn set_address_size(&mut self) { self.bits = self.bits | 0x2 }
+ fn cs(&self) -> bool { self.bits & 0x70 == 0x10 }
+ fn set_cs(&mut self) { self.bits = (self.bits & 0x8f) | 0x10 }
+ fn ds(&self) -> bool { self.bits & 0x70 == 0x20 }
+ fn set_ds(&mut self) { self.bits = (self.bits & 0x8f) | 0x20 }
+ fn es(&self) -> bool { self.bits & 0x70 == 0x30 }
+ fn set_es(&mut self) { self.bits = (self.bits & 0x8f) | 0x30 }
+ fn fs(&self) -> bool { self.bits & 0x70 == 0x40 }
+ fn set_fs(&mut self) { self.bits = (self.bits & 0x8f) | 0x40 }
+ fn gs(&self) -> bool { self.bits & 0x70 == 0x50 }
+ fn set_gs(&mut self) { self.bits = (self.bits & 0x8f) | 0x50 }
+ fn ss(&self) -> bool { self.bits & 0x70 == 0x60 }
+ fn set_ss(&mut self) { self.bits = (self.bits & 0x8f) | 0x60 }
+ fn rex(&self) -> &PrefixRex { &self.rex }
+ fn rex_mut(&mut self) -> &mut PrefixRex { &mut self.rex }
+}
+
+impl PrefixRex {
+ fn set_present(&mut self) { self.bits |= 0x10 }
+ fn present(&self) -> bool { (self.bits & 0x10) == 0x10 }
+ fn set_b(&mut self) { self.bits |= 0x01 }
+ fn b(&self) -> bool { (self.bits & 0x01) == 0x01 }
+ fn set_x(&mut self) { self.bits |= 0x02 }
+ fn x(&self) -> bool { (self.bits & 0x02) == 0x02 }
+ fn set_r(&mut self) { self.bits |= 0x04 }
+ fn r(&self) -> bool { (self.bits & 0x04) == 0x04 }
+ fn set_w(&mut self) { self.bits |= 0x08 }
+ fn w(&self) -> bool { (self.bits & 0x08) == 0x08 }
+ fn from(&mut self, prefix: u8) {
+ self.bits = prefix & 0x0f;
+ self.set_present();
+ }
+}
+
+impl fmt::Display for Instruction {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ if self.prefixes.lock {
+ write!(f, "lock ");
+ }
+ write!(f, "{}", self.opcode);
+ match &self.operands[0] {
+ &Operand::Nothing => {
+ return Ok(());
+ },
+ x @ &_ => {
+ write!(f, " {}", x)
+ }
+ };
+ match &self.operands[1] {
+ &Operand::Nothing => {
+ return Ok(());
+ },
+ x @ &_ => {
+ write!(f, ", {}", x)
+ }
+ }
+ }
+}
+
+#[derive(Copy, Clone, Debug)]
+pub enum OperandCode {
+ ModRM_0xf7,
+ Gv_Ev_Iv,
+ Gb_Eb_Ib,
+ Yb_DX,
+ Yv_DX,
+ DX_Xb,
+ DX_Xv,
+ OR,
+ AH,
+ AL_Ib,
+ AL_Ob,
+ AL_Xb,
+ AX_AL,
+ AX_Ivd,
+ AX_Ov,
+ AX_Xv,
+ DX_AX,
+ ModRM_0xc0_Eb_Ib,
+ ModRM_0xd0_Eb_1,
+ ModRM_0xd2_Eb_CL,
+ ModRM_0xfe_Eb,
+ ModRM_0x8f_Ev,
+ ModRM_0xc1_Ev_Ib,
+ ModRM_0xd1_Ev_1,
+ ModRM_0xd3_Ev_CL,
+ ModRM_0xff_Ev,
+ ModRM_0x80_Eb_Ib,
+ ModRM_0x81_Ev_Ivs,
+ ModRM_0x83_Ev_Ibs,
+ ModRM_0xc6_Eb_Ib,
+ ModRM_0xc7_Ev_Iv,
+ Eb_Gb,
+ Ev_Gv,
+ Ev_Ivs,
+ Ev,
+ Ew_Sw,
+ Fw,
+ Gb_Eb,
+ Gv_Ev,
+ Gv_M,
+ I_3,
+ Ib,
+ Ibs,
+ Ivs,
+ Iw,
+ Iw_Ib,
+ Jvds,
+ Jbs,
+ Ob_AL,
+ Ov_AX,
+ Sw_Ew,
+ Yb_AL,
+ Yb_Xb,
+ Yv_AX,
+ Yv_Xv,
+ Zb_Ib(u8),
+ Zv(u8),
+ Zv_AX(u8),
+ Zv_Ivq(u8),
+ Nothing,
+ Implied
+}
+
+const BASE_OPCODE_MAP: [Opcode; 8] = [
+ Opcode::ADD,
+ Opcode::OR,
+ Opcode::ADC,
+ Opcode::SBB,
+ Opcode::AND,
+ Opcode::SUB,
+ Opcode::XOR,
+ Opcode::CMP
+];
+
+const BITWISE_OPCODE_MAP: [Opcode; 8] = [
+ Opcode::ROL,
+ Opcode::ROR,
+ Opcode::RCL,
+ Opcode::RCR,
+ Opcode::SHL,
+ Opcode::SHR,
+ Opcode::SAL,
+ Opcode::SAR
+];
+
+fn read_opcode_0f_map(bytes_iter: &mut Iterator<Item=&u8>, instruction: &mut Instruction, prefixes: Prefixes) -> Result<OperandCode, String> {
+ match bytes_iter.next() {
+ Some(b) => {
+ match *b {
+ 0x1f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::NOP;
+ Ok(OperandCode::Ev)
+ },
+ 0x40 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVO;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x41 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVNO;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x42 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVB;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x43 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVNB;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x44 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVZ;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x45 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVNZ;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x46 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVNA;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x47 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVA;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x48 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVS;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x49 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVNS;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x4a => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVP;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x4b => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVNP;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x4c => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVL;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x4d => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVGE;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x4e => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVLE;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x4f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMOVG;
+ Ok(OperandCode::Gv_Ev)
+ },
+ 0x80 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JO;
+ Ok(OperandCode::Jvds)
+ },
+ 0x81 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JNO;
+ Ok(OperandCode::Jvds)
+ },
+ 0x82 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JB;
+ Ok(OperandCode::Jvds)
+ },
+ 0x83 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JNB;
+ Ok(OperandCode::Jvds)
+ },
+ 0x84 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JZ;
+ Ok(OperandCode::Jvds)
+ },
+ 0x85 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JNZ;
+ Ok(OperandCode::Jvds)
+ },
+ 0x86 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JNA;
+ Ok(OperandCode::Jvds)
+ },
+ 0x87 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JA;
+ Ok(OperandCode::Jvds)
+ },
+ 0x88 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JS;
+ Ok(OperandCode::Jvds)
+ },
+ 0x89 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JNS;
+ Ok(OperandCode::Jvds)
+ },
+ 0x8a => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JP;
+ Ok(OperandCode::Jvds)
+ },
+ 0x8b => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JNP;
+ Ok(OperandCode::Jvds)
+ },
+ 0x8c => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JL;
+ Ok(OperandCode::Jvds)
+ },
+ 0x8d => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JGE;
+ Ok(OperandCode::Jvds)
+ },
+ 0x8e => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JLE;
+ Ok(OperandCode::Jvds)
+ },
+ 0x8f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JG;
+ Ok(OperandCode::Jvds)
+ },
+ 0xb0 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMPXCHG;
+ Ok(OperandCode::Eb_Gb)
+ },
+ 0xb1 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMPXCHG;
+ Ok(OperandCode::Ev_Gv)
+ }
+ _ => {
+ Err(format!("Unknown opcode: 0f{:x}", b))
+ }
+ }
+ },
+ None => {
+ Err("No more bytes".to_owned())
+ }
+ }
+}
+
+fn read_opcode(bytes_iter: &mut Iterator<Item=&u8>, instruction: &mut Instruction) -> Result<OperandCode, String> {
+ use std::hint::unreachable_unchecked;
+// use std::intrinsics::unlikely;
+ let mut reading = true;
+ let mut prefixes = Prefixes::new(0);
+ let mut two_byte_map = false;
+ loop {
+ match bytes_iter.next() {
+ Some(b) => {
+ match *b {
+ x if x < 0x40 => {
+ if x % 8 > 5 { // unsafe { unlikely(x % 8 > 5) } {
+ // for x86_32 this is push/pop prefixes and 0x0f escape
+ // for x86_64 this is mostly invalid
+ match x {
+ 0x0f => {
+ return read_opcode_0f_map(bytes_iter, instruction, prefixes);
+ },
+ 0x26 => {
+ prefixes.set_es()
+ },
+ 0x2e => {
+ prefixes.set_cs()
+ },
+ 0x36 => {
+ prefixes.set_ss()
+ },
+ 0x3e => {
+ prefixes.set_ds()
+ },
+ 0x06
+ | 0x07
+ | 0x0e
+ | 0x16
+ | 0x17
+ | 0x1e
+ | 0x1f
+ | 0x27
+ | 0x2f
+ | 0x37
+ | 0x3f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::Nothing);
+ },
+ _ => { unsafe { unreachable_unchecked(); } }// panic!("unreachable?")
+ }
+ continue;
+ }
+ let op = BASE_OPCODE_MAP[(x / 8) as usize].clone();
+ let operand_code = [
+ OperandCode::Eb_Gb,
+ OperandCode::Ev_Gv,
+ OperandCode::Gb_Eb,
+ OperandCode::Gv_Ev,
+ OperandCode::AL_Ib,
+ OperandCode::AX_Ivd
+ ][(x % 8) as usize].clone();
+
+ instruction.prefixes = prefixes;
+ instruction.opcode = op;
+ return Ok(operand_code);
+ },
+ x if x < 0x50 => {
+ // x86_32 inc/dec
+ // x86_64 rex
+ prefixes.rex_mut().from(x);
+ },
+ x if x < 0x60 => {
+ let op = if x < 0x58 { Opcode::PUSH } else { Opcode::POP };
+ instruction.prefixes = prefixes;
+ instruction.opcode = op;
+ return Ok(OperandCode::Zv(x));
+ },
+ 0x64 => {
+ prefixes.set_fs();
+ },
+ 0x65 => {
+ prefixes.set_gs();
+ },
+ 0x66 => {
+ prefixes.set_operand_size();
+ },
+ 0x67 => {
+ prefixes.set_address_size();
+ },
+ 0x68 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::PUSH;
+ return Ok(OperandCode::Ivs);
+ },
+ 0x69 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::IMUL;
+ return Ok(OperandCode::Gv_Ev_Iv);
+ },
+ 0x6a => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::PUSH;
+ return Ok(OperandCode::Ibs);
+ },
+ 0x6b => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::IMUL;
+ return Ok(OperandCode::Gb_Eb_Ib);
+ },
+ 0x6c => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::INS;
+ return Ok(OperandCode::Yb_DX);
+ },
+ 0x6d => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::INS;
+ return Ok(OperandCode::Yv_DX);
+ },
+ 0x6e => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::OUTS;
+ return Ok(OperandCode::DX_Xb);
+ },
+ 0x6f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::OUTS;
+ return Ok(OperandCode::DX_Xv);
+ },
+ x if x < 0x80 => {
+ let op = [
+ Opcode::JO,
+ Opcode::JNO,
+ Opcode::JB,
+ Opcode::JNB,
+ Opcode::JZ,
+ Opcode::JNZ,
+ Opcode::JNA,
+ Opcode::JA,
+ Opcode::JS,
+ Opcode::JNS,
+ Opcode::JP,
+ Opcode::JNP,
+ Opcode::JL,
+ Opcode::JGE,
+ Opcode::JLE,
+ Opcode::JG
+ ][(x & 0xf) as usize].clone();
+ instruction.prefixes = prefixes;
+ instruction.opcode = op;
+ return Ok(OperandCode::Jbs);
+ }
+ x if x < 0x84 => {
+ // oh right op depends on modrm....
+ if x == 0x82 {
+ return (Err("invalid opcode".to_owned()));
+ } else {
+ let op = Opcode::Invalid;
+ let operand = if x == 0x80 {
+ OperandCode::ModRM_0x80_Eb_Ib
+ } else if x == 0x81 {
+ OperandCode::ModRM_0x81_Ev_Ivs
+ } else {
+ OperandCode::ModRM_0x83_Ev_Ibs
+ };
+ instruction.prefixes = prefixes;
+ instruction.opcode = op;
+ return Ok(operand);
+ }
+ },
+ 0x84 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::TEST;
+ return Ok(OperandCode::Eb_Gb);
+ },
+ 0x85 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::TEST;
+ return Ok(OperandCode::Ev_Gv);
+ },
+ 0x86 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::XCHG;
+ return Ok(OperandCode::Gb_Eb);
+ },
+ 0x87 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::XCHG;
+ return Ok(OperandCode::Gv_Ev);
+ },
+ 0x88 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Eb_Gb);
+ }
+ 0x89 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Ev_Gv);
+ }
+ 0x8a => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Gb_Eb);
+ }
+ 0x8b => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Gv_Ev);
+ }
+ 0x8c => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Ew_Sw);
+ }
+ 0x8d => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::LEA;
+ return Ok(OperandCode::Gv_M);
+ }
+ 0x8e => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Sw_Ew);
+ },
+ 0x8f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::ModRM_0x8f_Ev);
+ },
+ 0x90 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::NOP;
+ return Ok(OperandCode::Nothing);
+ },
+ x if x < 0x98 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::XCHG;
+ return Ok(OperandCode::Zv_AX(x));
+ },
+ 0x98 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CBW;
+ return Ok(OperandCode::AX_AL);
+ },
+ 0x99 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CBW;
+ return Ok(OperandCode::DX_AX);
+ },
+ 0x9a => { return Err("invalid opcode".to_owned()); },
+ 0x9b => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::WAIT;
+ return Ok(OperandCode::Nothing);
+ }
+ 0x9c => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::PUSHF;
+ return Ok(OperandCode::Fw);
+ },
+ 0x9d => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::POPF;
+ return Ok(OperandCode::Fw);
+ },
+ 0x9e => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::SAHF;
+ return Ok(OperandCode::AH);
+ },
+ 0x9f => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::LAHF;
+ return Ok(OperandCode::AH);
+ },
+ 0xa0 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::AL_Ob);
+ },
+ 0xa1 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::AX_Ov);
+ },
+ 0xa2 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Ob_AL);
+ },
+ 0xa3 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::Ov_AX);
+ },
+ 0xa4 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOVS;
+ return Ok(OperandCode::Yb_Xb);
+ },
+ 0xa5 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOVS;
+ return Ok(OperandCode::Yv_Xv);
+ },
+ 0xa6 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMPS;
+ return Ok(OperandCode::Yb_Xb);
+ },
+ 0xa7 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CMPS;
+ return Ok(OperandCode::Yv_Xv);
+ },
+ 0xa8 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::TEST;
+ return Ok(OperandCode::AL_Ib);
+ },
+ 0xa9 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::TEST;
+ return Ok(OperandCode::AX_Ivd);
+ },
+ 0xaa => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::STOS;
+ return Ok(OperandCode::Yb_AL);
+ },
+ 0xab => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::STOS;
+ return Ok(OperandCode::Yv_AX);
+ },
+ 0xac => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::LODS;
+ return Ok(OperandCode::AL_Xb);
+ },
+ 0xad => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::LODS;
+ return Ok(OperandCode::AX_Xv);
+ },
+ 0xae => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::SCAS;
+ return Ok(OperandCode::Yb_AL);
+ },
+ 0xaf => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::SCAS;
+ return Ok(OperandCode::Yv_AX);
+ },
+ x if x < 0xc0 => {
+ let operand = if x < 0xb8 {
+ OperandCode::Zb_Ib(x)
+ } else {
+ OperandCode::Zv_Ivq(x)
+ };
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(operand);
+ },
+ 0xc0 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::ModRM_0xc0_Eb_Ib);
+ },
+ 0xc1 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::ModRM_0xc1_Ev_Ib);
+ },
+ 0xc2 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::RETURN;
+ return Ok(OperandCode::Iw);
+ },
+ 0xc3 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::RETURN;
+ return Ok(OperandCode::Nothing);
+ },
+ 0xc4 | 0xc5 => {
+ return Err("invalid opcode".to_owned());
+ },
+ 0xc6 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::ModRM_0xc6_Eb_Ib);
+ },
+ 0xc7 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::MOV;
+ return Ok(OperandCode::ModRM_0xc7_Ev_Iv);
+ },
+ 0xc8 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::ENTER;
+ return Ok(OperandCode::Iw_Ib);
+ },
+ 0xc9 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::LEAVE;
+ return Ok(OperandCode::Nothing);
+ },
+ 0xca => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::RETF;
+ return Ok(OperandCode::Iw);
+ }
+ 0xcb => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::RETF;
+ return Ok(OperandCode::Nothing);
+ }
+ 0xcc => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::INT;
+ return Ok(OperandCode::I_3);
+ },
+ 0xcd => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::INT;
+ return Ok(OperandCode::Ib);
+ },
+ 0xce => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::INTO;
+ return Ok(OperandCode::Fw);
+ },
+ 0xcf => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::IRET;
+ return Ok(OperandCode::Fw);
+ },
+ x if x < 0xd4 => {
+ let operand = [
+ OperandCode::ModRM_0xd0_Eb_1,
+ OperandCode::ModRM_0xd1_Ev_1,
+ OperandCode::ModRM_0xd2_Eb_CL,
+ OperandCode::ModRM_0xd3_Ev_CL
+ ][(x & 0x3) as usize].clone();
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(operand);
+ },
+ // TODO: GAP
+ 0xe8 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::CALL;
+ return Ok(OperandCode::Jvds);
+ },
+ 0xe9 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JMP;
+ return Ok(OperandCode::Jvds);
+ },
+ 0xeb => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::JMP;
+ return Ok(OperandCode::Jbs);
+ },
+ 0xf0 => {
+ prefixes.set_lock();
+ },
+ 0xf2 => {
+ prefixes.set_repnz();
+ },
+ 0xf3 => {
+ prefixes.set_rep();
+ },
+ 0xf4 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::HLT;
+ return Ok(OperandCode::Nothing);
+ },
+ 0xf6 => { },
+ 0xf7 => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::ModRM_0xf7);
+ },
+ 0xfe => {
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::ModRM_0xfe_Eb);
+ },
+ 0xff => {
+ // TODO: test 0xff /3
+ instruction.prefixes = prefixes;
+ instruction.opcode = Opcode::Invalid;
+ return Ok(OperandCode::ModRM_0xff_Ev);
+ },
+ _ => {
+ return Err("unsupported opcode".to_owned());
+ }
+ }
+ },
+ None => {
+ return Err("no more bytes".to_owned());
+ }
+ }
+ }
+}
+
+fn read_E(bytes_iter: &mut Iterator<Item=&u8>, prefixes: &Prefixes, m: u8, modbits: u8, width: u8, result: &mut Operand) -> Result<(), String> {
+ if modbits == 0b11 {
+ if prefixes.rex().b() {
+ *result = Operand::Register(RegSpec {
+ num: m + 0b1000,
+ bank: width_to_gp_reg_bank(width)
+ });
+ return Ok(());
+ } else {
+ *result = Operand::Register(RegSpec {
+ num: m,
+ bank: width_to_gp_reg_bank(width)
+ });
+ return Ok(());
+ }
+ } else if m == 5 && modbits == 0b00 {
+ let disp = read_num(bytes_iter, 4);
+ *result = Operand::RegDisp(RegSpec {
+ num: 0,
+ // this is determined by prefixes not ... operand width
+ bank: if width == 4 { RegisterBank::EIP } else { RegisterBank::RIP }
+ }, disp as i32);
+ Ok(())
+ } else if m == 4 {
+ let sibbyte = *bytes_iter.next().unwrap();
+ let (ss, index, base) = octets_of(sibbyte);
+
+// println!("scale: {:b}, index: {:b}, base: {:b}", ss, index, base);
+
+ if base == 0b101 {
+ let disp = if modbits == 0b00 {
+ read_num(bytes_iter, 4)
+ } else if modbits == 0b01 {
+ read_num(bytes_iter, 1)
+ } else {
+ read_num(bytes_iter, 4)
+ };
+
+ if index == 0b100 {
+ if modbits == 0b00 && !prefixes.rex().x() {
+ *result = Operand::DisplacementU32(disp as i32);
+ Ok(())
+ } else {
+ let indexnum = if prefixes.rex().x() {
+ 0b1000 + 0b100
+ } else {
+ 0b100
+ };
+
+ if disp == 0 {
+ *result = Operand::RegDeref(RegSpec {
+ num: indexnum,
+ bank: width_to_gp_reg_bank(width)
+ });
+ Ok(())
+ } else {
+ *result = Operand::RegDisp(RegSpec {
+ num: indexnum,
+ bank: width_to_gp_reg_bank(width)
+ }, disp as i32);
+ Ok(())
+ }
+ }
+ } else {
+ let base_reg = if prefixes.rex().b() {
+ RegSpec {
+ num: 5 + 0b1000,
+ bank: width_to_gp_reg_bank(width)
+ }
+ } else {
+ RegSpec {
+ num: 5,
+ bank: width_to_gp_reg_bank(width)
+ }
+ };
+
+ let index_reg = if prefixes.rex().x() {
+ RegSpec {
+ num: index + 0b1000,
+ bank: width_to_gp_reg_bank(width)
+ }
+ } else {
+ RegSpec {
+ num: index,
+ bank: width_to_gp_reg_bank(width)
+ }
+ };
+
+ match (ss, modbits, disp) {
+ (0, 0b00, 0) => {
+ *result = Operand::RegDeref(index_reg);
+ Ok(())
+ },
+ (0, 0b00, _) => {
+ *result = Operand::RegDisp(index_reg, disp as i32);
+ Ok(())
+ },
+ (0, _, 0) => {
+ *result = Operand::RegIndexBase(base_reg, index_reg);
+ Ok(())
+ },
+ (0, _, _) => {
+ *result = Operand::RegIndexBaseDisp(base_reg, index_reg, disp as i32);
+ Ok(())
+ },
+ (_, 0b00, 0) => {
+ *result = Operand::RegScale(index_reg, 1u8 << ss);
+ Ok(())
+ },
+ (_, 0b00, _) => {
+ *result = Operand::RegScaleDisp(index_reg, 1u8 << ss, disp as i32);
+ Ok(())
+ },
+ (_, _, 0) => {
+ *result = Operand::RegIndexBaseScale(base_reg, index_reg, 1u8 << ss);
+ Ok(())
+ },
+ (_, _, _) => {
+ *result = Operand::RegIndexBaseScaleDisp(base_reg, index_reg, 1u8 << ss, disp as i32);
+ Ok(())
+ }
+ }
+ }
+ } else {
+ let base_reg = if prefixes.rex().b() {
+ RegSpec {
+ num: base + 0b1000,
+ bank: width_to_gp_reg_bank(width)
+ }
+ } else {
+ RegSpec {
+ num: base,
+ bank: width_to_gp_reg_bank(width)
+ }
+ };
+
+ let disp = if modbits == 0b00 {
+ 0
+ } else if modbits == 0b01 {
+ read_num(bytes_iter, 1)
+ } else {
+ read_num(bytes_iter, 4)
+ };
+
+ if index == 0b100 {
+ if disp == 0 {
+ *result = Operand::RegDeref(base_reg);
+ Ok(())
+ } else {
+ *result = Operand::RegDisp(base_reg, disp as i32);
+ Ok(())
+ }
+ } else {
+ let index_reg = RegSpec {
+ num: index,
+ bank: width_to_gp_reg_bank(width)
+ };
+ if disp == 0 {
+ *result = Operand::RegIndexBaseScale(base_reg, index_reg, ss);
+ Ok(())
+ } else {
+ *result = Operand::RegIndexBaseScaleDisp(base_reg, index_reg, ss, disp as i32);
+ Ok(())
+ }
+ }
+ }
+ } else {
+ let regidx = m + if prefixes.rex().b() { 0b1000 } else { 0 };
+ if modbits == 0b00 {
+ *result = Operand::RegDeref(RegSpec {
+ num: regidx,
+ bank: width_to_gp_reg_bank(width) // TODO: arch width
+ });
+ Ok(())
+ } else {
+ let disp_width = if modbits == 0b01 { 1 } else { 4 };
+ let disp = read_num(bytes_iter, disp_width) as i32;
+ *result = Operand::RegDisp(RegSpec {
+ num: regidx,
+ bank: width_to_gp_reg_bank(width) // TODO: arch width
+ }, disp);
+ Ok(())
+ }
+ }
+}
+
+fn read_operands(
+ bytes_iter: &mut Iterator<Item=&u8>,
+ instruction: &mut Instruction,
+ operand_code: OperandCode
+) -> Result<(), String> {
+ match operand_code {
+ /*
+ Gv_Ev_Iv,
+ Gb_Eb_Ib,
+ Yb_DX,
+ Yv_DX,
+ DX_Xb,
+ DX_Xv,
+ OR,
+ AH,
+ AL_Ib,
+ AL_Ob,
+ AL_Xb,
+ AX_AL,
+ AX_Ivd,
+ AX_Ov,
+ AX_Xv,
+ DX_AX,
+ Eb_1,
+ Eb_Ib,
+ Eb_CL,
+ Ev,
+ Ev_1,
+ Ev_CL,
+ Ev_Ibs,
+ Ev_Iv,
+ Ev_Ivs,
+ Ew_Sw,
+ Fw,
+ Gv_M,
+ I_3,
+ Ib,
+ Ibs,
+ Ivs,
+ Iw,
+ Iw_Ib,
+ Ob_AL,
+ Ov_AX,
+ Sw_Ew,
+ Yb_AL,
+ Yb_Xb,
+ Yv_AX,
+ Yv_Xv,
+ Zb_Ib,
+ Zv,
+ Zv_AX,
+ */
+ OperandCode::ModRM_0x80_Eb_Ib => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let num = read_num(bytes_iter, 1) as i8;
+ let opcode = BASE_OPCODE_MAP[r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::ImmediateI8(num);
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xc0_Eb_Ib => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let num = read_num(bytes_iter, 1) as i8;
+ let opcode = BITWISE_OPCODE_MAP[r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::ImmediateI8(num);
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xc1_Ev_Ib => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let num = read_num(bytes_iter, 1) as i8;
+ let opcode = BITWISE_OPCODE_MAP[r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::ImmediateI8(num);
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xc6_Eb_Ib => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let num = read_num(bytes_iter, 1) as i8;
+ if r != 0 {
+ return (Err("modrm invalid".to_owned()));
+ }
+ instruction.opcode = Opcode::MOV;
+ instruction.operands[1] = Operand::ImmediateI8(num);
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xc7_Ev_Iv => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(e_op) => {
+ match read_imm_unsigned(bytes_iter, opwidth) {
+ Ok(imm) => {
+ instruction.opcode = Opcode::MOV;
+ instruction.operands[1] = imm;
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xd0_Eb_1 => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let opcode = BITWISE_OPCODE_MAP[r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::ImmediateI8(1);
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xd1_Ev_1 => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let opcode = BITWISE_OPCODE_MAP[r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::ImmediateI8(1);
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0xf7 => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => { },
+ Err(reason) => { return Err(reason); }
+ };
+ match r {
+ 0 | 1 => {
+ instruction.opcode = Opcode::TEST;
+ let numwidth = if opwidth == 8 { 4 } else { opwidth };
+ match read_imm_signed(bytes_iter, numwidth, opwidth) {
+ Ok(imm) => {
+ instruction.operands[1] = imm;
+ },
+ Err(reason) => { return Err(reason); }
+ }
+ },
+ 2 => {
+ instruction.opcode = Opcode::NOT;
+ },
+ 3 => {
+ instruction.opcode = Opcode::NEG;
+ },
+ 4 => {
+ instruction.opcode = Opcode::MUL;
+ },
+ 5 => {
+ instruction.opcode = Opcode::IMUL;
+ },
+ 6 => {
+ instruction.opcode = Opcode::DIV;
+ },
+ 7 => {
+ instruction.opcode = Opcode::IDIV;
+ },
+ _ => {
+ unsafe { unreachable_unchecked(); }
+ }
+ }
+ Ok(())
+ },
+ OperandCode::ModRM_0xfe_Eb => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let opcode = [
+ Opcode::INC,
+ Opcode::DEC,
+ Opcode::Invalid,
+ Opcode::Invalid,
+ Opcode::Invalid,
+ Opcode::Invalid,
+ Opcode::Invalid,
+ Opcode::Invalid
+ ][r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::Nothing;
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ }
+ OperandCode::ModRM_0xff_Ev => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let opcode = [
+ Opcode::INC,
+ Opcode::DEC,
+ Opcode::CALL,
+ Opcode::CALLF,
+ Opcode::JMP,
+ Opcode::JMPF,
+ Opcode::PUSH,
+ Opcode::Invalid
+ ][r as usize].clone();
+ instruction.opcode = opcode;
+ instruction.operands[1] = Operand::Nothing;
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ }
+ OperandCode::Ev => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ instruction.operands[1] = Operand::Nothing;
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::Eb_Gb => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ instruction.operands[1] =
+ Operand::Register(RegSpec {
+ num: r,
+ // TODO: test rex
+ bank: width_to_gp_reg_bank(opwidth)
+ });
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::Ev_Gv => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ instruction.operands[1] =
+ Operand::Register(RegSpec {
+ num: r,
+ bank: width_to_gp_reg_bank(opwidth)
+ });
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::Gb_Eb => {
+ let opwidth = 1;
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[1]) {
+ Ok(()) => {
+ instruction.operands[0] =
+ Operand::Register(RegSpec {
+ num: r,
+ bank: width_to_gp_reg_bank(opwidth)
+ });
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ // TODO: verify M
+ OperandCode::Gv_Ev | OperandCode::Gv_M => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ // TODO: ...
+ let modrm = bytes_iter.next().unwrap();
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+// println!("mod_bits: {:2b}, r: {:3b}, m: {:3b}", mod_bits, r, m);
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[1]) {
+ Ok(()) => {
+ instruction.operands[0] =
+ Operand::Register(RegSpec {
+ num: r,
+ bank: width_to_gp_reg_bank(opwidth)
+ });
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::Zv_Ivq(opcode_byte) => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ let reg_idx = opcode_byte & 0x7;
+ match read_imm_ivq(bytes_iter, opwidth) {
+ Ok(imm) => {
+ instruction.operands = [
+ Operand::Register(RegSpec {
+ num: reg_idx,
+ bank: width_to_gp_reg_bank(opwidth)
+ }),
+ imm
+ ];
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::AX_Ivd => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+ let numwidth = if opwidth == 8 { 4 } else { opwidth };
+ match read_imm_signed(bytes_iter, numwidth, opwidth) {
+ Ok(imm) => {
+ instruction.operands = [
+ Operand::Register(RegSpec {
+ num: 0,
+ bank: width_to_gp_reg_bank(opwidth)
+ }),
+ imm
+ ];
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ }
+ OperandCode::Zb_Ib(opcode_byte) => {
+ let reg_idx = opcode_byte & 0x7;
+ match read_imm_unsigned(bytes_iter, 1) {
+ Ok(imm) => {
+ instruction.operands = [
+ Operand::Register(RegSpec {
+ num: reg_idx,
+ bank: width_to_gp_reg_bank(1)
+ }),
+ imm];
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::Iw => {
+ match read_imm_unsigned(bytes_iter, 2) {
+ Ok(imm) => {
+ instruction.operands = [imm, Operand::Nothing];
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ }
+ OperandCode::Jbs => {
+ // TODO: arch width (8 in 64, 4 in 32, 2 in 16)
+ match read_imm_signed(bytes_iter, 1, 8) {
+ Ok(imm) => {
+ instruction.operands = [imm, Operand::Nothing];
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::ModRM_0x83_Ev_Ibs => {
+ let modrm = bytes_iter.next().unwrap();
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vqp, &instruction.prefixes);
+
+ let (mod_bits, r, m) = octets_of(*modrm);
+
+ match read_E(bytes_iter, &instruction.prefixes, m, mod_bits, opwidth, &mut instruction.operands[0]) {
+ Ok(()) => {
+ let opcode = BASE_OPCODE_MAP[r as usize].clone();
+
+ instruction.opcode = opcode;
+ match read_imm_signed(bytes_iter, 1, opwidth) {
+ Ok(op) => {
+ instruction.operands[1] = op;
+ Ok(())
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ Err(reason) => Err(reason)
+ }
+ },
+ OperandCode::Zv(opcode_byte) => {
+ let opwidth = imm_width_from_prefixes_64(SizeCode::vq, &instruction.prefixes);
+ let index = (opcode_byte & 0b111) + if instruction.prefixes.rex().b() { 0b1000 } else { 0 };
+ instruction.operands = [Operand::Register(RegSpec {
+ num: index,
+ bank: width_to_gp_reg_bank(opwidth)
+ }), Operand::Nothing];
+ Ok(())
+ },
+ OperandCode::Jbs => {
+ let offset = read_num(bytes_iter, 1);
+ instruction.operands = [Operand::ImmediateI8(offset as i8), Operand::Nothing];
+ Ok(())
+ },
+ OperandCode::Jvds => {
+ let offset = read_num(bytes_iter, 4);
+ instruction.operands = [Operand::ImmediateI32(offset as i32), Operand::Nothing];
+ Ok(())
+ }
+ OperandCode::Nothing => {
+ instruction.operands = [Operand::Nothing, Operand::Nothing];
+ Ok(())
+ }
+ _ => {
+ // use std::hint::unreachable_unchecked;
+ Err(format!("unsupported operand code: {:?}", operand_code))
+ // unsafe { unreachable_unchecked(); }
+ }
+ }
+}
+
+fn width_to_gp_reg_bank(width: u8) -> RegisterBank {
+ use std::hint::unreachable_unchecked;
+ match width {
+ 1 => return RegisterBank::B,
+ 2 => return RegisterBank::W,
+ 4 => return RegisterBank::D,
+ 8 => return RegisterBank::Q,
+ _ => unsafe { unreachable_unchecked(); }
+ }
+}
+
+pub fn decode_one<'a, 'b, T: IntoIterator<Item=&'a u8>>(bytes: T, instr: &'b mut Instruction) -> Option<()> {
+ let mut bytes_iter = bytes.into_iter();
+ match read_opcode(&mut bytes_iter, instr) {
+ Ok(operand_code) => {
+ match read_operands(&mut bytes_iter, instr, operand_code) {
+ Ok(()) => {
+ Some(())
+ },
+ Err(reason) => {
+ panic!("Decode error on operand: {:?}", reason);
+ // println!("Invalid instruction: {}", reason);
+// return Instruction::invalid()
+ None
+ }
+ }
+ }
+ Err(reason) => {
+ panic!("Decode error on opcode: {:?}", reason);
+ // println!("Invalid instruction: {}", reason);
+// return Instruction::invalid()
+ None
+ }
+ }
+}
+
+fn read_num(bytes: &mut Iterator<Item=&u8>, width: u8) -> u64 {
+ let mut result = 0u64;
+ let mut idx = 0;
+ loop {
+ if idx == width {
+ return result;
+ }
+ let byte = *bytes.next().unwrap();
+ result |= (byte as u64) << (idx * 8);
+ idx += 1;
+ }
+}
+
+fn read_imm_ivq(bytes: &mut Iterator<Item=&u8>, width: u8) -> Result<Operand, String> {
+ match width {
+ 2 => {
+ Ok(Operand::ImmediateU16(read_num(bytes, 2) as u16))
+ },
+ 4 => {
+ Ok(Operand::ImmediateU32(read_num(bytes, 4) as u32))
+ },
+ 8 => {
+ Ok(Operand::ImmediateU64(read_num(bytes, 8) as u64))
+ },
+ _ => {
+ unsafe { unreachable_unchecked(); }
+ }
+ }
+}
+
+fn read_imm_signed(bytes: &mut Iterator<Item=&u8>, num_width: u8, extend_to: u8) -> Result<Operand, String> {
+ match num_width {
+ 1 => {
+ let num = read_num(bytes, 1) as i8;
+ match extend_to {
+ 1 => { Ok(Operand::ImmediateI8(num)) },
+ 2 => { Ok(Operand::ImmediateI16(num as i16)) },
+ 4 => { Ok(Operand::ImmediateI32(num as i32)) },
+ 8 => { Ok(Operand::ImmediateI64(num as i64)) },
+ _ => { unsafe { unreachable_unchecked(); } }
+ }
+ },
+ 2 => {
+ let num = read_num(bytes, 2) as i16;
+ match extend_to {
+ 1 => { Ok(Operand::ImmediateI8(num as i8)) },
+ 2 => { Ok(Operand::ImmediateI16(num)) },
+ 4 => { Ok(Operand::ImmediateI32(num as i32)) },
+ 8 => { Ok(Operand::ImmediateI64(num as i64)) },
+ _ => { unsafe { unreachable_unchecked(); } }
+ }
+ },
+ 4 => {
+ let num = read_num(bytes, 4) as i32;
+ match extend_to {
+ 1 => { Ok(Operand::ImmediateI8(num as i8)) },
+ 2 => { Ok(Operand::ImmediateI16(num as i16)) },
+ 4 => { Ok(Operand::ImmediateI32(num)) },
+ 8 => { Ok(Operand::ImmediateI64(num as i64)) },
+ _ => { unsafe { unreachable_unchecked(); } }
+ }
+ },
+ 8 => {
+ let num = read_num(bytes, 4) as i32;
+ match extend_to {
+ 1 => { Ok(Operand::ImmediateI8(num as i8)) },
+ 2 => { Ok(Operand::ImmediateI16(num as i16)) },
+ 4 => { Ok(Operand::ImmediateI32(num)) },
+ 8 => { Ok(Operand::ImmediateI64(num as i64)) },
+ _ => { unsafe { unreachable_unchecked(); } }
+ }
+ },
+ _ => { unsafe { unreachable_unchecked(); } }
+ }
+}
+
+fn read_imm_unsigned(bytes: &mut Iterator<Item=&u8>, width: u8) -> Result<Operand, String> {
+ match width {
+ 1 => {
+ Ok(Operand::ImmediateU8(read_num(bytes, 1) as u8))
+ },
+ 2 => {
+ Ok(Operand::ImmediateU16(read_num(bytes, 2) as u16))
+ },
+ 4 => {
+ Ok(Operand::ImmediateU32(read_num(bytes, 4) as u32))
+ },
+ 8 => {
+ Ok(Operand::ImmediateU64(read_num(bytes, 4) as u64))
+ }
+ _ => {
+ unsafe { unreachable_unchecked(); }
+ }
+ }
+}
+
+fn octets_of(byte: u8) -> (u8, u8, u8) {
+ (byte >> 6 & 0b11, (byte >> 3) & 0b111, byte & 0b111)
+}
+
+fn imm_width_from_prefixes_64(interpretation: SizeCode, prefixes: &Prefixes) -> u8 {
+ match interpretation {
+ SizeCode::b => 1,
+ SizeCode::vd => {
+ if prefixes.rex().w() || !prefixes.operand_size() { 4 } else { 2 }
+ },
+ SizeCode::vq => {
+ // TODO: this should be address_size
+ // but i'm not sure if that breaks other instructions rn
+ if prefixes.operand_size() {
+ 2
+ } else {
+ 8 // TODO: this 8 should be arch width.
+ }
+ },
+ SizeCode::vqp => {
+ if prefixes.rex().w() {
+ 8
+ } else if prefixes.operand_size() {
+ 2
+ } else {
+ 4
+ }
+ },
+ }
+}