From 1186a66e8cc48f4c0c424fdfb63aa4f752db7166 Mon Sep 17 00:00:00 2001 From: iximeow Date: Sat, 5 Jan 2019 02:00:37 -0800 Subject: initial --- src/lib.rs | 2040 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 2040 insertions(+) create mode 100644 src/lib.rs (limited to 'src') diff --git a/src/lib.rs b/src/lib.rs new file mode 100644 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), + 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, instruction: &mut Instruction, prefixes: Prefixes) -> Result { + 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, instruction: &mut Instruction) -> Result { + 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, 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, + 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>(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, 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, width: u8) -> Result { + 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, num_width: u8, extend_to: u8) -> Result { + 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, width: u8) -> Result { + 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 + } + }, + } +} -- cgit v1.1