diff options
author | iximeow <me@iximeow.net> | 2019-06-16 19:48:28 -0700 |
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committer | iximeow <me@iximeow.net> | 2020-01-12 17:28:07 -0800 |
commit | c3c921435028e42abdd25268ebf546337ecfb755 (patch) | |
tree | 0073bd31b722aca4176a0e891faf1c56403f7345 /src/armv8/a64.rs | |
parent | 40a6f250cc1a879840099f38d6d5f27e658a7344 (diff) |
add armv8/a64 support
Diffstat (limited to 'src/armv8/a64.rs')
-rw-r--r-- | src/armv8/a64.rs | 2734 |
1 files changed, 2734 insertions, 0 deletions
diff --git a/src/armv8/a64.rs b/src/armv8/a64.rs new file mode 100644 index 0000000..e3953e3 --- /dev/null +++ b/src/armv8/a64.rs @@ -0,0 +1,2734 @@ +#[cfg(feature="use-serde")] +use serde::{Serialize, Deserialize}; + +use std::fmt::{Display, Formatter}; + +use yaxpeax_arch::{Arch, Colorize, Colored, ColorSettings, Decodable, LengthedInstruction, ShowContextual, YaxColors}; + +mod docs { + #[test] + fn test_ones() { + assert_eq!(Ones(0), 0x00); + assert_eq!(Ones(1), 0x01); + assert_eq!(Ones(2), 0x03); + assert_eq!(Ones(3), 0x07); + assert_eq!(Ones(4), 0x0f); + assert_eq!(Ones(5), 0x1f); + assert_eq!(Ones(6), 0x3f); + assert_eq!(Ones(7), 0x7f); + assert_eq!(Ones(8), 0xff); + } + + fn Ones(len: u8) -> u64 { + assert!(len <= 64); + + if len == 0 { return 0; } + if len == 64 { return 0xffffffff_ffffffffu64; } + + let mask = (0x8000_0000_0000_0000i64 >> ((64 - 1) - len)) as u64; + !mask + } + + #[test] + fn test_highest_set_bit() { + assert_eq!(HighestSetBit(1, 0x11), 0); + assert_eq!(HighestSetBit(5, 0x11), 4); + assert_eq!(HighestSetBit(8, 0x08), 3); + } + + fn HighestSetBit(N: u8, bits: u64) -> u8 { + let mut probe = 1u64 << (N - 1); + let mut i = N - 1; + loop { + if bits & probe != 0 { + return i; + } + + if i == 0 { + break; + } else { + probe = probe >> 1; + i -= 1; + } + } + + return 0xff; + } + + fn Replicate(bitsM: u64, M_size: u8, N: u8) -> u64 { + let count = N / M_size; + let mut res = bitsM; + for i in 1..count { + res |= bitsM << M_size * i; + } + // since this produces a u64, we might have a few extra non-zero bits set. + let res_mask = Ones(N); + res & res_mask + } + + fn ROR(bits: u64, bitsN: u8, shift: u8) -> u64 { + if shift == 0 { + bits + } else { + let m = shift % bitsN; + (bits >> m) | (bits << (bitsN - m)) + } + } + + // helper functions from the ARMv8 Architecture Reference Manual + pub fn DecodeBitMasks_32(immN: u8, imms: u8, immr: u8) -> (u32, u32) { + // should the !imms be ~imms + let len = HighestSetBit(7, ((immN << 6) | ((!imms) & 0x3f)) as u64); + + let levels = (Ones(len) & 0x3f) as u8; // should ZeroExtend to at least 6 bits, but this is u8. + + let S = imms & levels; + let R = immr & levels; + let diff = S.wrapping_sub(R); + + let esize = 1 << len; + let d = diff & !(0xff << len); + let welem = Ones(S + 1); + let telem = Ones(d + 1); + let wmask = Replicate(ROR(welem, esize, R), esize, 32) as u32; + let tmask = Replicate(telem, esize, 32) as u32; + (wmask, tmask) + } + + pub fn DecodeBitMasks_64(immN: u8, imms: u8, immr: u8) -> (u64, u64) { + // should the !imms be ~imms + let len = HighestSetBit(7, ((immN << 6) | ((!imms) & 0x3f)) as u64); + + let levels = (Ones(len) & 0x3f) as u8; // should ZeroExtend to at least 6 bits, but this is u8. + + let S = imms & levels; + let R = immr & levels; + let diff = S.wrapping_sub(R); + + let esize = 1 << len; + let d = diff & !(0xff << len); + let welem = Ones(S + 1); + let telem = Ones(d + 1); + let wmask = Replicate(ROR(welem, esize, R), esize, 64); + let tmask = Replicate(telem, esize, 64); + (wmask, tmask) + } +} + +#[derive(Copy, Clone, Debug)] +pub struct ARMv8 { } + +impl Arch for ARMv8 { + type Address = u64; + type Instruction = Instruction; + type Operand = Operand; +} + +#[derive(Copy, Clone, Debug, PartialEq)] +pub enum SizeCode { X, W } + +#[derive(Copy, Clone, Debug, PartialEq)] +pub struct Instruction { + pub opcode: Opcode, + pub operands: [Operand; 4], +} + +impl Display for Instruction { + fn fmt(&self, fmt: &mut Formatter) -> std::fmt::Result { + match self.opcode { + Opcode::Invalid => { + write!(fmt, "invalid")?; + }, + Opcode::MOVN => { + write!(fmt, "movn")?; + }, + Opcode::MOVK => { + write!(fmt, "movk")?; + }, + Opcode::MOVZ => { + write!(fmt, "movz")?; + }, + Opcode::ADC => { + write!(fmt, "adc")?; + }, + Opcode::ADCS => { + write!(fmt, "adcs")?; + }, + Opcode::SBC => { + write!(fmt, "sbc")?; + }, + Opcode::SBCS => { + write!(fmt, "sbcs")?; + }, + Opcode::AND => { + write!(fmt, "and")?; + }, + Opcode::ORR => { + write!(fmt, "orr")?; + }, + Opcode::EOR => { + write!(fmt, "eor")?; + }, + Opcode::ANDS => { + write!(fmt, "ands")?; + }, + Opcode::ADDS => { + write!(fmt, "adds")?; + }, + Opcode::ADD => { + if let Operand::Immediate(0) = self.operands[2] { + if let Operand::Register(_, 31) = self.operands[0] { + return write!(fmt, "mov {}, {}", self.operands[0], self.operands[1]); + } else if let Operand::RegisterOrSP(_, 31) = self.operands[1] { + return write!(fmt, "mov {}, {}", self.operands[0], self.operands[1]); + } + } + write!(fmt, "add")?; + }, + Opcode::SUBS => { + if let Operand::Register(_, 31) = self.operands[0] { + return write!(fmt, "cmp {}, {}", self.operands[1], self.operands[2]) + } + write!(fmt, "subs")?; + }, + Opcode::SUB => { + write!(fmt, "sub")?; + }, + Opcode::BFM => { + write!(fmt, "bfm")?; + }, + Opcode::UBFM => { + write!(fmt, "ubfm")?; + }, + Opcode::SBFM => { + if let Operand::Immediate(0) = self.operands[2] { + if let Operand::Immediate(7) = self.operands[3] { + return write!(fmt, "sxtb {}, {}", self.operands[0], self.operands[1]); + } else if let Operand::Immediate(15) = self.operands[3] { + return write!(fmt, "sxth {}, {}", self.operands[0], self.operands[1]); + } else if let Operand::Immediate(31) = self.operands[3] { + return write!(fmt, "sxtw {}, {}", self.operands[0], self.operands[1]); + } + } else if let Operand::Immediate(63) = self.operands[3] { + if let Operand::Register(SizeCode::X, _) = self.operands[0] { + return write!(fmt, "asr {}, {}, {}", self.operands[0], self.operands[1], self.operands[2]); + } + } else if let Operand::Immediate(31) = self.operands[3] { + if let Operand::Register(SizeCode::W, _) = self.operands[0] { + return write!(fmt, "asr {}, {}, {}", self.operands[0], self.operands[1], self.operands[2]); + } + } + write!(fmt, "sbfm")?; + }, + Opcode::ADR => { + write!(fmt, "adr")?; + }, + Opcode::ADRP => { + write!(fmt, "adrp")?; + }, + Opcode::EXTR => { + write!(fmt, "extr")?; + }, + Opcode::LDP => { + write!(fmt, "ldp")?; + }, + Opcode::LDPSW => { + write!(fmt, "ldpsw")?; + }, + Opcode::LDR => { + write!(fmt, "ldr")?; + }, + Opcode::LDRB => { + write!(fmt, "ldrb")?; + }, + Opcode::LDRSB => { + write!(fmt, "ldrsb")?; + }, + Opcode::LDRSH => { + write!(fmt, "ldrsh")?; + }, + Opcode::LDRSW => { + write!(fmt, "ldrsw")?; + }, + Opcode::LDRH => { + write!(fmt, "ldrh")?; + }, + Opcode::LDTR => { + write!(fmt, "ldtr")?; + }, + Opcode::LDTRB => { + write!(fmt, "ldtrb")?; + }, + Opcode::LDTRSB => { + write!(fmt, "ldtrsb")?; + }, + Opcode::LDTRSH => { + write!(fmt, "ldtrsh")?; + }, + Opcode::LDTRSW => { + write!(fmt, "ldtrsw")?; + }, + Opcode::LDTRH => { + write!(fmt, "ldtrh")?; + }, + Opcode::LDUR => { + write!(fmt, "ldur")?; + }, + Opcode::LDURB => { + write!(fmt, "ldurb")?; + }, + Opcode::LDURSB => { + write!(fmt, "ldursb")?; + }, + Opcode::LDURSW => { + write!(fmt, "ldursw")?; + }, + Opcode::LDURSH => { + write!(fmt, "ldursh")?; + }, + Opcode::LDURH => { + write!(fmt, "ldurh")?; + }, + Opcode::LDAR => { + write!(fmt, "ldar")?; + }, + Opcode::LDARB => { + write!(fmt, "ldarb")?; + }, + Opcode::LDAXRB => { + write!(fmt, "ldaxrb")?; + }, + Opcode::LDARH => { + write!(fmt, "ldarh")?; + }, + Opcode::LDAXP => { + write!(fmt, "ldaxp")?; + }, + Opcode::LDAXR => { + write!(fmt, "ldaxr")?; + }, + Opcode::LDAXRH => { + write!(fmt, "ldaxrh")?; + }, + Opcode::LDXP => { + write!(fmt, "ldxp")?; + }, + Opcode::LDXR => { + write!(fmt, "ldxr")?; + }, + Opcode::LDXRB => { + write!(fmt, "ldxrb")?; + }, + Opcode::LDXRH => { + write!(fmt, "ldxrh")?; + }, + Opcode::STP => { + write!(fmt, "stp")?; + }, + Opcode::STR => { + write!(fmt, "str")?; + }, + Opcode::STRB => { + write!(fmt, "strb")?; + }, + Opcode::STRH => { + write!(fmt, "strh")?; + }, + Opcode::STRW => { + write!(fmt, "strw")?; + }, + Opcode::STTR => { + write!(fmt, "sttr")?; + }, + Opcode::STTRB => { + write!(fmt, "sttrb")?; + }, + Opcode::STTRH => { + write!(fmt, "sttrh")?; + }, + Opcode::STUR => { + write!(fmt, "stur")?; + }, + Opcode::STURB => { + write!(fmt, "sturb")?; + }, + Opcode::STURH => { + write!(fmt, "sturh")?; + }, + Opcode::STLR => { + write!(fmt, "stlr")?; + }, + Opcode::STLRB => { + write!(fmt, "stlrb")?; + }, + Opcode::STLRH => { + write!(fmt, "stlrh")?; + }, + Opcode::STLXP => { + write!(fmt, "stlxp")?; + }, + Opcode::STLXR => { + write!(fmt, "stlxr")?; + }, + Opcode::STLXRB => { + write!(fmt, "stlxrb")?; + }, + Opcode::STLXRH => { + write!(fmt, "stlxrh")?; + }, + Opcode::STXP => { + write!(fmt, "stxp")?; + }, + Opcode::STXR => { + write!(fmt, "stxr")?; + }, + Opcode::STXRB => { + write!(fmt, "stxrb")?; + }, + Opcode::STXRH => { + write!(fmt, "stxrh")?; + }, + Opcode::TBZ => { + write!(fmt, "tbz")?; + }, + Opcode::TBNZ => { + write!(fmt, "tbnz")?; + }, + Opcode::CBZ => { + write!(fmt, "cbz")?; + }, + Opcode::CBNZ => { + write!(fmt, "cbnz")?; + }, + Opcode::B => { + write!(fmt, "b")?; + }, + Opcode::BR => { + write!(fmt, "br")?; + }, + Opcode::Bcc(cond) => { + write!(fmt, "b.{}", Operand::ConditionCode(cond))?; + }, + Opcode::BL => { + write!(fmt, "bl")?; + }, + Opcode::BLR => { + write!(fmt, "blr")?; + }, + Opcode::SVC => { + write!(fmt, "svc")?; + }, + Opcode::HVC => { + write!(fmt, "hvc")?; + }, + Opcode::SMC => { + write!(fmt, "smc")?; + }, + Opcode::BRK => { + write!(fmt, "brk")?; + }, + Opcode::HLT => { + write!(fmt, "hlt")?; + }, + Opcode::DCPS1 => { + write!(fmt, "dcps1")?; + }, + Opcode::DCPS2 => { + write!(fmt, "dcps2")?; + }, + Opcode::DCPS3 => { + write!(fmt, "dcps3")?; + }, + Opcode::RET => { + write!(fmt, "ret")?; + if let Operand::Register(SizeCode::X, 30) = self.operands[0] { + // C5.6.148: Defaults to X30 if absent. + // so ret x30 is probably expected to be read as just `ret` + return Ok(()); + } + }, + Opcode::ERET => { + write!(fmt, "eret")?; + }, + Opcode::DRPS => { + write!(fmt, "drps")?; + }, + Opcode::MSRa(a, b) => { + write!(fmt, "msr(a) {}, {}", a, b)?; + } + Opcode::MSRb(a) => { + write!(fmt, "msr(b) {:#x}", a)?; + } + Opcode::MRS(v) => { + write!(fmt, "mrs({:#x})", v)?; + } + Opcode::SYS => { + write!(fmt, "sys")?; + } + Opcode::SYSL => { + write!(fmt, "sys")?; + } + Opcode::ISB => { + write!(fmt, "isb")?; + } + Opcode::DSB => { + write!(fmt, "dsb")?; + } + Opcode::DMB => { + write!(fmt, "dmb")?; + } + Opcode::HINT(v) => { + match v { + 0 => { write!(fmt, "nop")?; }, + 1 => { write!(fmt, "yield")?; }, + 2 => { write!(fmt, "wfe")?; }, + 3 => { write!(fmt, "wfi")?; }, + 4 => { write!(fmt, "sev")?; }, + 5 => { write!(fmt, "sevl")?; }, + _ => { write!(fmt, "hint({:#x})", v)?; } + } + } + Opcode::CLREX => { + write!(fmt, "clrex")?; + } + Opcode::CSEL => { + write!(fmt, "csel")?; + } + Opcode::CSNEG => { + write!(fmt, "csneg")?; + } + Opcode::CSINC => { + match (self.operands[1], self.operands[2], self.operands[3]) { + (Operand::Register(_, n), Operand::Register(_, m), Operand::ConditionCode(cond)) => { + if n == m && cond < 0b1110 { + if n == 31 { + return write!(fmt, "cset {}, {}", self.operands[0], Operand::ConditionCode(cond ^ 0x01)); + } else { + return write!(fmt, "cinc {}, {}, {}", self.operands[0], self.operands[1], Operand::ConditionCode(cond ^ 0x01)); + } + } + } + _ => {} + } + write!(fmt, "csinc")?; + } + Opcode::CSINV => { + match (self.operands[1], self.operands[2], self.operands[3]) { + (Operand::Register(_, n), Operand::Register(_, m), Operand::ConditionCode(cond)) => { + if n == m && n != 31 && cond < 0b1110 { + return write!(fmt, "cinv {}, {}, {}", self.operands[0], self.operands[1], Operand::ConditionCode(cond ^ 0x01)) + } + } + _ => {} + } + write!(fmt, "csinv")?; + } + }; + + if self.operands[0] != Operand::Nothing { + write!(fmt, " {}", self.operands[0]); + } else { + return Ok(()); + } + + if self.operands[1] != Operand::Nothing { + write!(fmt, ", {}", self.operands[1]); + } else { + return Ok(()); + } + + if self.operands[2] != Operand::Nothing { + write!(fmt, ", {}", self.operands[2]); + } else { + return Ok(()); + } + + if self.operands[3] != Operand::Nothing { + write!(fmt, ", {}", self.operands[3]); + } else { + return Ok(()); + } + + Ok(()) + } +} + +impl LengthedInstruction for Instruction { + type Unit = <ARMv8 as Arch>::Address; + fn len(&self) -> Self::Unit { 4 } + fn min_size() -> Self::Unit { 4 } +} + +impl Instruction { + pub fn blank() -> Self { + Instruction { + opcode: Opcode::Invalid, + operands: [Operand::Nothing, Operand::Nothing, Operand::Nothing, Operand::Nothing] + } + } +} + +#[derive(Copy, Clone, Debug, PartialEq)] +pub enum Opcode { + Invalid, + MOVN, + MOVK, + MOVZ, + ADC, + ADCS, + SBC, + SBCS, + AND, + ORR, + EOR, + ANDS, + ADDS, + ADD, + SUBS, + SUB, + BFM, + UBFM, + SBFM, + ADR, + ADRP, + EXTR, + LDAR, + LDARB, + LDAXRB, + LDARH, + LDAXP, + LDAXR, + LDAXRH, + LDP, + LDPSW, + LDR, + LDRB, + LDRSB, + LDRSW, + LDRSH, + LDRH, + LDTR, + LDTRB, + LDTRH, + LDTRSB, + LDTRSH, + LDTRSW, + LDUR, + LDURB, + LDURSB, + LDURSW, + LDURSH, + LDURH, + LDXP, + LDXR, + LDXRB, + LDXRH, + STLR, + STLRB, + STLRH, + STLXP, + STLXR, + STLXRB, + STLXRH, + STP, + STR, + STTR, + STTRB, + STTRH, + STRB, + STRH, + STRW, + STUR, + STURB, + STURH, + STXP, + STXR, + STXRB, + STXRH, + TBZ, + TBNZ, + CBZ, + CBNZ, + B, + BR, + Bcc(u8), + BL, + BLR, + SVC, + HVC, + SMC, + BRK, + HLT, + DCPS1, + DCPS2, + DCPS3, + RET, + ERET, + DRPS, + MSRa(u8, u8), + MSRb(u32), + MRS(u32), + SYS, + SYSL, + ISB, + DSB, + DMB, + HINT(u8), + CLREX, + CSEL, + CSNEG, + CSINC, + CSINV, +} + +#[derive(Copy, Clone, Debug, PartialEq)] +pub enum ShiftStyle { + LSL, + LSR, + ASR, + UXTB, + UXTH, + UXTW, + UXTX, + SXTB, + SXTH, + SXTW, + SXTX, +} + +impl Display for ShiftStyle { + fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result { + match self { + ShiftStyle::LSL => { write!(fmt, "lsl") }, + ShiftStyle::LSR => { write!(fmt, "lsr") }, + ShiftStyle::ASR => { write!(fmt, "asr") }, + ShiftStyle::UXTB => { write!(fmt, "uxtb") }, + ShiftStyle::UXTH => { write!(fmt, "uxth") }, + ShiftStyle::UXTW => { write!(fmt, "uxtw") }, + ShiftStyle::UXTX => { write!(fmt, "uxtx") }, + ShiftStyle::SXTB => { write!(fmt, "sxtb") }, + ShiftStyle::SXTH => { write!(fmt, "sxth") }, + ShiftStyle::SXTW => { write!(fmt, "sxtw") }, + ShiftStyle::SXTX => { write!(fmt, "sxtx") }, + } + } +} + +#[derive(Copy, Clone, Debug, PartialEq)] +pub enum Operand { + Nothing, + Register(SizeCode, u16), + RegisterOrSP(SizeCode, u16), + ConditionCode(u8), + Offset(u32), + PCOffset(u32), + Immediate(u32), + Imm64(u64), + Imm16(u16), + ImmShift(u16, u8), + RegShift(ShiftStyle, u8, SizeCode, u16), + RegOffset(u16, i16), + RegRegOffset(u16, SizeCode, u16, ShiftStyle, u8), + RegPreIndex(u16, i16), + RegPostIndex(u16, i16), +} + +impl Display for Operand { + fn fmt(&self, fmt: &mut Formatter) -> std::fmt::Result { + match self { + Operand::Nothing => { + unreachable!(); + }, + Operand::Register(size, reg) => { + if *reg == 31 { + match size { + SizeCode::X => { + write!(fmt, "xzr") + }, + SizeCode::W => { + write!(fmt, "wzr") + } + } + } else { + match size { + SizeCode::X => { + write!(fmt, "x{}", reg) + }, + SizeCode::W => { + write!(fmt, "w{}", reg) + } + } + } + }, + Operand::RegisterOrSP(size, reg) => { + if *reg == 31 { + match size { + SizeCode::X => { + write!(fmt, "sp") + }, + SizeCode::W => { + write!(fmt, "wsp") + } + } + } else { + match size { + SizeCode::X => { + write!(fmt, "x{}", reg) + }, + SizeCode::W => { + write!(fmt, "w{}", reg) + } + } + } + }, + Operand::ConditionCode(cond) => { + match cond { + 0b0000 => { write!(fmt, "eq") } + 0b0010 => { write!(fmt, "hs") } + 0b0100 => { write!(fmt, "mi") } + 0b0110 => { write!(fmt, "vs") } + 0b1000 => { write!(fmt, "hi") } + 0b1010 => { write!(fmt, "ge") } + 0b1100 => { write!(fmt, "gt") } + 0b1110 => { write!(fmt, "al") } + 0b0001 => { write!(fmt, "ne") } + 0b0011 => { write!(fmt, "lo") } + 0b0101 => { write!(fmt, "pl") } + 0b0111 => { write!(fmt, "vc") } + 0b1001 => { write!(fmt, "ls") } + 0b1011 => { write!(fmt, "lt") } + 0b1101 => { write!(fmt, "le") } + 0b1111 => { write!(fmt, "al") } + _ => { unreachable!(); } + } + } + Operand::Offset(offs) => { + write!(fmt, "$+{:#x}", offs) + } + Operand::PCOffset(offs) => { + write!(fmt, "$+{:#x}", offs) + } + Operand::Immediate(i) => { + write!(fmt, "{:#x}", i) + }, + Operand::Imm16(i) => { + write!(fmt, "{:#x}", *i) + }, + Operand::Imm64(i) => { + write!(fmt, "{:#x}", *i) + }, + Operand::ImmShift(i, shift) => { + match shift { + 0 => { + write!(fmt, "{:#x}", i) + }, + _ => { + write!(fmt, "{:#x}, lsl {}", i, shift * 16) + } + } + }, + Operand::RegShift(shift_type, amount, size, reg) => { + match size { + SizeCode::X => { + if *shift_type == ShiftStyle::LSL && *amount == 0 { + write!(fmt, "x{}", reg) + } else { + write!(fmt, "x{}, {} {}", reg, shift_type, amount) + } + }, + SizeCode::W => { + if *shift_type == ShiftStyle::LSL && *amount == 0 { + write!(fmt, "w{}", reg) + } else { + write!(fmt, "w{}, {} {}", reg, shift_type, amount) + } + } + } + } + Operand::RegOffset(reg, offset) => { + if *offset != 0 { + if *offset < 0 { + write!(fmt, "[{}, -{:#x}]", Operand::RegisterOrSP(SizeCode::X, *reg), -*offset) + } else { + write!(fmt, "[{}, {:#x}]", Operand::RegisterOrSP(SizeCode::X, *reg), offset) + } + } else { + write!(fmt, "[{}]", Operand::RegisterOrSP(SizeCode::X, *reg)) + } + } + Operand::RegRegOffset(reg, size_code, index_reg, extend, amount) => { + match size_code { + SizeCode::X => { + if *extend == ShiftStyle::LSL && *amount == 0 { + write!(fmt, "[x{}, x{}]", reg, index_reg) + } else { + write!(fmt, "[x{}, x{}, {} {}]", reg, index_reg, extend, amount) + } + }, + SizeCode::W => { + if *extend == ShiftStyle::LSL && *amount == 0 { + write!(fmt, "[x{}, w{}]", reg, index_reg) + } else { + write!(fmt, "[x{}, w{}, {} {}]", reg, index_reg, extend, amount) + } + } + } + } + Operand::RegPreIndex(reg, offset) => { + if *offset != 0 { + if *offset < 0 { + write!(fmt, "[{}, -{:#x}]!", Operand::RegisterOrSP(SizeCode::X, *reg), -*offset) + } else { + write!(fmt, "[{}, {:#x}]!", Operand::RegisterOrSP(SizeCode::X, *reg), offset) + } + } else { + write!(fmt, "[{}]!", Operand::RegisterOrSP(SizeCode::X, *reg)) + } + } + Operand::RegPostIndex(reg, offset) => { + if *offset != 0 { + if *offset < 0 { + write!(fmt, "[{}], -{:#x}", Operand::RegisterOrSP(SizeCode::X, *reg), -*offset) + } else { + write!(fmt, "[{}], {:#x}", Operand::RegisterOrSP(SizeCode::X, *reg), offset) + } + } else { + write!(fmt, "[{}]", Operand::RegisterOrSP(SizeCode::X, *reg)) + } + } + } + } +} + +#[allow(non_snake_case)] +impl Decodable for Instruction { + fn decode<T: IntoIterator<Item=u8>>(bytes: T) -> Option<Self> { + let mut blank = Instruction::blank(); + match blank.decode_into(bytes) { + Some(_) => Some(blank), + None => None + } + } + fn decode_into<T: IntoIterator<Item=u8>>(&mut self, bytes: T) -> Option<()> { + fn read_word<T: IntoIterator<Item=u8>>(bytes: T) -> Option<u32> { + let mut iter = bytes.into_iter(); + let instr: u32 = + ((iter.next()? as u32) ) | + ((iter.next()? as u32) << 8 ) | + ((iter.next()? as u32) << 16) | + ((iter.next()? as u32) << 24); + + Some(instr) + } + + let word = match read_word(bytes) { + Some(word) => word, + None => { return None; } + }; + + #[derive(Copy, Clone, Debug)] + enum Section { + Unallocated, + LoadStore, + DataProcessingReg, + DataProcessingSimd, + DataProcessingSimd2, + DataProcessingImmediate, + BranchExceptionSystem, + } + + // from ARM architecture refrence manual for ARMv8, C3.1 + + /* + * ---00--- UNALLOCATED + * ---100-- Data processing - immediate + * ---101-- Branch, exception, system instructions + * ----1-0- Loads and stores + * ----101- Data processing - register + * ---0111- Data processing - SIMD and floating point + * ---1111- Data processing - SIMD and floating point + */ + + let section_bits = word >> 25; + let section = [ + Section::Unallocated, // 0000 + Section::Unallocated, // 0001 + Section::Unallocated, // 0010 + Section::Unallocated, // 0011 + Section::LoadStore, // 0100 + Section::DataProcessingReg, // 0101 + Section::LoadStore, // 0110 + Section::DataProcessingSimd, // 0111 + Section::DataProcessingImmediate, // 1000 + Section::DataProcessingImmediate, // 1001 + Section::BranchExceptionSystem, // 1010 + Section::BranchExceptionSystem, // 1011 + Section::LoadStore, // 1100 + Section::DataProcessingReg, // 1101 + Section::LoadStore, // 1110 + Section::DataProcessingSimd2, // 1111 + ][(section_bits & 0x0f) as usize]; + + println!("word: {:#x}, bits: {:#b}", word, section_bits & 0xf); + + match section { + Section::DataProcessingSimd | + Section::DataProcessingSimd2 => { + unreachable!(); + } + Section::Unallocated => { + self.opcode = Opcode::Invalid; + } + Section::DataProcessingReg => { + /* + * Section C3.5. Data Processing - Register + * + * instructions here have the form + * XXXX101X_XXXXXXXX_XXXXXXXX_XXXXXXXX + */ + if (word & 0x10000000) != 0 { + // These are of the form + // XXX1101X_... + let group_bits = (word >> 22) & 0x7; + println!("Group bits: {:#b}", group_bits); + match group_bits { + 0b000 => { + // Add/subtract (with carry) + let Rd = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let opc2 = ((word >> 10) & 0x3f) as u16; + let Rm = ((word >> 16) & 0x1f) as u16; + + if opc2 == 0b000000 { + self.opcode = Opcode::Invalid; + return Some(()); + } + + let size_code = match word >> 29 { + 0b000 => { + self.opcode = Opcode::ADC; + SizeCode::W + } + 0b001 => { + self.opcode = Opcode::ADCS; + SizeCode::W + } + 0b010 => { + self.opcode = Opcode::SBC; + SizeCode::W + } + 0b011 => { + self.opcode = Opcode::SBCS; + SizeCode::W + } + 0b100 => { + self.opcode = Opcode::ADC; + SizeCode::X + } + 0b101 => { + self.opcode = Opcode::ADCS; + SizeCode::X + } + 0b110 => { + self.opcode = Opcode::SBC; + SizeCode::X + } + 0b111 => { + self.opcode = Opcode::SBCS; + SizeCode::X + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size_code, Rd), + Operand::Register(size_code, Rn), + Operand::Register(size_code, Rm), + Operand::Nothing + ]; + }, + 0b001 => { + // Conditional compare (register/immediate) + }, + 0b010 => { + // Conditional select + let op2 = (word >> 10) & 0x03; + let sf_op = (word >> 28) & 0x0c; + + if word & 0x20000000 != 0 { + self.opcode = Opcode::Invalid; + return Some(()); + } + + let size = match sf_op | op2 { + 0b0000 => { + self.opcode = Opcode::CSEL; + SizeCode::W + }, + 0b0001 => { + self.opcode = Opcode::CSINC; + SizeCode::W + }, + 0b0100 => { + self.opcode = Opcode::CSINV; + SizeCode::W + }, + 0b0101 => { + self.opcode = Opcode::CSNEG; + SizeCode::W + }, + 0b1000 => { + self.opcode = Opcode::CSEL; + SizeCode::X + }, + 0b1001 => { + self.opcode = Opcode::CSINC; + SizeCode::X + }, + 0b1100 => { + self.opcode = Opcode::CSINV; + SizeCode::X + }, + 0b1101 => { + self.opcode = Opcode::CSNEG; + SizeCode::X + }, + 0b0010 | + 0b0011 | + 0b0110 | + 0b0111 | + 0b1010 | + 0b1011 | + 0b1110 | + 0b1111 => { + self.opcode = Opcode::Invalid; + return Some(()); + }, + _ => { + unreachable!(); + } + }; + + let Rd = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let Rm = ((word >> 16) & 0x1f) as u16; + let cond = ((word >> 12) & 0x0f) as u8; + + self.operands = [ + Operand::Register(size, Rd), + Operand::Register(size, Rn), + Operand::Register(size, Rm), + Operand::ConditionCode(cond) + ]; + }, + 0b011 => { + // Data processing (1 source, 2 source) + }, + _ => { + // Data processing (3 source) + } + } + } else { + // These are of the form + // XXX0101X_... + // so bits 21 and 24 fully distinguish categories here... + // but bit 21 distinguishes between add/sub shifted/extended, which + // we can deal with later. so use bit 24 to figure out the instruction + // class, first. + if (word & 0x01000000) == 0 { + // Logical (shifted register) + // XXX01010X_... + unreachable!(); + } else { + // Add/subtract ({shifted,extended} register) + // XXX11011X_... + // specific instruction is picked by the first two bits.. + self.opcode = [ + Opcode::ADD, + Opcode::ADDS, + Opcode::SUB, + Opcode::SUBS + ][((word >> 29) as usize) & 0x03]; + + let sf = (word >> 31) == 1; + let size = if sf { SizeCode::X } else { SizeCode::W }; + + // and operands are contingent on bit 21 + if (word & 0x20000) != 0 { + // extended form + // opt (bits 22, 23) must be 0 + + if (word >> 22) & 0x03 != 0 { + self.opcode = Opcode::Invalid; + return None; + } + + let Rd = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let imm3 = (word >> 10) & 0x07; + let option = (word >> 13) & 0x07; + let Rm = ((word >> 16) & 0x1f) as u16; + + self.operands[0] = Operand::Register(size, Rd); + self.operands[1] = Operand::Register(size, Rn); + + let shift = (imm3 * 16) as u8; + self.operands[2] = match option { + 0b000 => Operand::RegShift(ShiftStyle::UXTB, shift, SizeCode::W, Rm), + 0b001 => Operand::RegShift(ShiftStyle::UXTH, shift, SizeCode::W, Rm), + 0b010 => Operand::RegShift(ShiftStyle::UXTW, shift, SizeCode::W, Rm), + 0b011 => Operand::RegShift(ShiftStyle::UXTX, shift, SizeCode::X, Rm), + 0b100 => Operand::RegShift(ShiftStyle::SXTB, shift, SizeCode::W, Rm), + 0b101 => Operand::RegShift(ShiftStyle::SXTH, shift, SizeCode::W, Rm), + 0b110 => Operand::RegShift(ShiftStyle::SXTW, shift, SizeCode::W, Rm), + 0b111 => Operand::RegShift(ShiftStyle::SXTX, shift, SizeCode::X, Rm), + _ => { unreachable!(); }, + }; + } else { + // shifted form + + let shift = (word >> 22) & 0x03; + if shift == 0b11 { + self.opcode = Opcode::Invalid; + return None; + } + + let Rd = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let imm6 = ((word >> 10) & 0x3f) as u8; + let Rm = ((word >> 16) & 0x1f) as u16; + + if size == SizeCode::W && imm6 >= 32 { + self.opcode = Opcode::Invalid; + return None; + } + + self.operands[0] = Operand::Register(size, Rd); + self.operands[1] = Operand::Register(size, Rn); + + self.operands[2] = match shift { + 0b00 => Operand::RegShift(ShiftStyle::LSL, imm6, size, Rm), + 0b01 => Operand::RegShift(ShiftStyle::LSR, imm6, size, Rm), + 0b10 => Operand::RegShift(ShiftStyle::ASR, imm6, size, Rm), + _ => { unreachable!(); }, + }; + } + } + } + }, + Section::DataProcessingImmediate => { + /* + * Section C3.4, Data processing - immediate + * This collects bits 23:25, which are the only ones that vary in this category + */ + let group_bits = (word >> 23) & 0x7; + match group_bits { + 0b000 | + 0b001 => { + // PC-rel addressing + if word >= 0x80000000 { + self.opcode = Opcode::ADRP; + let imm = ((word >> 3) & 0x1ffffc) | ((word >> 29) & 0x3); + self.operands = [ + Operand::Register(SizeCode::X, (word & 0x1f) as u16), + Operand::Immediate(imm * 0x1000), + Operand::Nothing, + Operand::Nothing + ]; + } else { + self.opcode = Opcode::ADR; + let imm = ((word >> 3) & 0x1ffffc) | ((word >> 29) & 0x3); + self.operands = [ + Operand::Register(SizeCode::X, (word & 0x1f) as u16), + Operand::Immediate(imm), + Operand::Nothing, + Operand::Nothing + ]; + }; + + } + 0b010 | + 0b011 => { + // add/sub imm + let Rd = word & 0x1f; + let Rn = (word >> 5) & 0x1f; + let imm12 = (word >> 10) & 0xfff; + let shift = (word >> 22) & 0x3; + let size = match word >> 29 { + 0b000 => { + self.opcode = Opcode::ADD; + SizeCode::W + }, + 0b001 => { + self.opcode = Opcode::ADDS; + SizeCode::W + }, + 0b010 => { + self.opcode = Opcode::SUB; + SizeCode::W + }, + 0b011 => { + self.opcode = Opcode::SUBS; + SizeCode::W + }, + 0b100 => { + self.opcode = Opcode::ADD; + SizeCode::X + }, + 0b101 => { + self.opcode = Opcode::ADDS; + SizeCode::X + }, + 0b110 => { + self.opcode = Opcode::SUB; + SizeCode::X + }, + 0b111 => { + self.opcode = Opcode::SUBS; + SizeCode::X + }, + _ => { + unreachable!(); + } + }; + self.operands[0] = Operand::Register(size, Rd as u16); + self.operands[1] = Operand::RegisterOrSP(size, Rn as u16); + self.operands[2] = match shift { + 0b00 => { + Operand::Immediate(imm12 as u32) + }, + 0b01 => { + Operand::Immediate((imm12 << 12) as u32) + }, + 0b10 | + 0b11 => { + self.opcode = Opcode::Invalid; + return None; + } + _ => { unreachable!(); } + }; + self.operands[3] = Operand::Nothing; + } + 0b100 => { + // logical (imm) + let Rd = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let imms = (word >> 10) & 0x3f; + let immr = (word >> 16) & 0x3f; + let N = (word >> 22) & 1; + let size = match word >> 29 { + 0b000 => { + self.opcode = Opcode::AND; + SizeCode::W + } + 0b001 => { + self.opcode = Opcode::ORR; + SizeCode::W + } + 0b010 => { + self.opcode = Opcode::EOR; + SizeCode::W + } + 0b011 => { + self.opcode = Opcode::ANDS; + SizeCode::W + } + 0b100 => { + self.opcode = Opcode::AND; + SizeCode::X + } + 0b101 => { + self.opcode = Opcode::ORR; + SizeCode::X + } + 0b110 => { + self.opcode = Opcode::EOR; + SizeCode::X + } + 0b111 => { + self.opcode = Opcode::ANDS; + SizeCode::X + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rd), + Operand::Register(size, Rn), + match size { + SizeCode::W => Operand::Immediate(docs::DecodeBitMasks_32(N as u8, imms as u8, immr as u8).0), + SizeCode::X => Operand::Imm64(docs::DecodeBitMasks_64(N as u8, imms as u8, immr as u8).0) + }, + Operand::Nothing + ]; + }, + 0b101 => { + // move wide (imm) + let Rd = word & 0x1f; + let imm16 = (word >> 5) & 0xffff; + let hw = (word >> 21) & 0x3; + let size = match word >> 29 { + 0b000 => { + if hw >= 0x10 { + self.opcode = Opcode::Invalid; + } else { + self.opcode = Opcode::MOVN; + } + SizeCode::W + }, + 0b001 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + 0b010 => { + if hw >= 0x10 { + self.opcode = Opcode::Invalid; + } else { + self.opcode = Opcode::MOVZ; + } + SizeCode::W + }, + 0b011 => { + if hw >= 0x10 { + self.opcode = Opcode::Invalid; + } else { + self.opcode = Opcode::MOVK; + } + SizeCode::W + }, + 0b100 => { + self.opcode = Opcode::MOVN; + SizeCode::X + }, + 0b101 => { + self.opcode = Opcode::Invalid; + SizeCode::X + } + 0b110 => { + self.opcode = Opcode::MOVZ; + SizeCode::X + }, + 0b111 => { + self.opcode = Opcode::MOVK; + SizeCode::X + }, + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rd as u16), + Operand::ImmShift(imm16 as u16, hw as u8), + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b110 => { + // bitfield + let Rd = word & 0x1f; + let Rn = (word >> 5) & 0x1f; + let imms = (word >> 10) & 0x3f; + let immr = (word >> 16) & 0x3f; + let N = (word >> 22) & 0x1; + + let sf_opc = word >> 29; + + let size = match sf_opc { + 0b000 => { + if N == 0 { + self.opcode = Opcode::SBFM; + } else { + self.opcode = Opcode::Invalid; + } + SizeCode::W + } + 0b001 => { + if N == 0 { + self.opcode = Opcode::BFM; + } else { + self.opcode = Opcode::Invalid; + } + SizeCode::W + } + 0b010 => { + if N == 0 { + self.opcode = Opcode::UBFM; + } else { + self.opcode = Opcode::Invalid; + } + SizeCode::W + } + 0b011 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + 0b100 => { + if N == 1 { + self.opcode = Opcode::SBFM; + } else { + self.opcode = Opcode::Invalid; + } + SizeCode::X + } + 0b101 => { + if N == 1 { + self.opcode = Opcode::SBFM; + } else { + self.opcode = Opcode::Invalid; + } + SizeCode::X + } + 0b110 => { + if N == 1 { + self.opcode = Opcode::SBFM; + } else { + self.opcode = Opcode::Invalid; + } + SizeCode::X + } + 0b111 => { + self.opcode = Opcode::Invalid; + SizeCode::X + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rd as u16), + Operand::Register(size, Rn as u16), + Operand::Immediate(immr as u32), + Operand::Immediate(imms as u32) + ]; + }, + 0b111 => { + // extract + let Rd = word & 0x1f; + let Rn = (word >> 5) & 0x1f; + let imms = (word >> 10) & 0x3f; + let Rm = (word >> 16) & 0x1f; + let No0 = (word >> 21) & 0x3; + + let sf_op21 = word >> 29; + + if sf_op21 == 0b000 { + if No0 != 0b00 || imms >= 0x10 { + self.opcode = Opcode::Invalid; + } else { + self.opcode = Opcode::EXTR; + } + } else if sf_op21 == 0b100 { + if No0 != 0b10 { + self.opcode = Opcode::Invalid; + } else { + self.opcode = Opcode::EXTR; + } + } else { + self.opcode = Opcode::Invalid; + } + unreachable!(); + } + _ => { unreachable!() } + } + }, + Section::LoadStore => { + /* + * This corresponds to section C3.3, Loads and stores. + * Specifically, instructions in this category are all of the form + * + * v _ G G 1 G 0 G G _ v v v v v v _ _ _ _ v v __________ + * + * where G+v variants indicate which instruction class the word is in. + * + * however! the G bits are sufficient to distinguish most class of instruction. + */ + + let group_byte = word >> 23; + let group_bits = (group_byte & 0x03) | ((group_byte >> 1) & 0x04) | ((group_byte >> 2) & 0x18); + + println!("Group byte: {:#b}, bits: {:#b}", group_byte, group_bits); + match group_bits { + 0b00000 => { + let Rt = word & 0x1f; + let Rn = (word >> 5) & 0x1f; + let Rt2 = (word >> 10) & 0x1f; + let o0 = word & 0x0080; + let Rs = (word >> 16) & 0x1f; + let Lo1 = word & 0x600000; + let size = (word >> 29) & 0x3; + // load/store exclusive + // o2 == 0 + self.opcode = match (size, Lo1, o0) { + (0b00, 0b00, 0b0) => Opcode::STXRB, + (0b00, 0b00, 0b1) => Opcode::STLXRB, + (0b00, 0b10, 0b0) => Opcode::LDXRB, + (0b00, 0b10, 0b1) => Opcode::LDAXRB, + (0b01, 0b00, 0b0) => Opcode::STXRH, + (0b01, 0b00, 0b1) => Opcode::STLXRH, + (0b01, 0b10, 0b0) => Opcode::LDXRH, + (0b01, 0b10, 0b1) => Opcode::LDAXRH, + (0b10, 0b00, 0b0) => Opcode::STXR, // 32-bit + (0b10, 0b00, 0b1) => Opcode::STLXR, // 32-bit + (0b10, 0b01, 0b0) => Opcode::STXP, // 32-bit + (0b10, 0b01, 0b1) => Opcode::STLXP, // 32-bit + (0b10, 0b10, 0b0) => Opcode::LDXR, // 32-bit + (0b10, 0b10, 0b1) => Opcode::LDAXR, // 32-bit + (0b10, 0b11, 0b0) => Opcode::LDXP, // 32-bit + (0b10, 0b11, 0b1) => Opcode::LDAXP, // 32-bit + (0b11, 0b00, 0b0) => Opcode::STXR, // 64-bit + (0b11, 0b00, 0b1) => Opcode::STLXR, // 64-bit + (0b11, 0b01, 0b0) => Opcode::STXP, // 64-bit + (0b11, 0b01, 0b1) => Opcode::STLXP, // 64-bit + (0b11, 0b10, 0b0) => Opcode::LDXR, // 64-bit + (0b11, 0b10, 0b1) => Opcode::LDAXR, // 64-bit + (0b11, 0b11, 0b0) => Opcode::LDXP, // 64-bit + (0b11, 0b11, 0b1) => Opcode::LDAXP, // 64-bit + _ => { + Opcode::Invalid + } + } + }, + 0b00001 => { + let Rt = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let Rt2 = ((word >> 10) & 0x1f) as u16; + let o0 = (word >> 15) & 1; + let Rs = (word >> 16) & 0x1f; + let Lo1 = (word >> 21) & 0x3; + let size = (word >> 30) & 0x3; + // load/store exclusive + // o2 == 1 + println!("Word: {:#b}", word); + self.opcode = match (size, Lo1, o0) { + (0b00, 0b00, 0b1) => Opcode::STLRB, + (0b00, 0b10, 0b1) => Opcode::LDARB, + (0b01, 0b00, 0b1) => Opcode::STLRH, + (0b01, 0b10, 0b1) => Opcode::LDARH, + (0b10, 0b00, 0b1) => Opcode::STLR, // 32-bit + (0b10, 0b10, 0b1) => Opcode::LDAR, // 32-bit + (0b11, 0b00, 0b1) => Opcode::STLR, // 64-bit + (0b11, 0b10, 0b1) => Opcode::LDAR, // 64-bit + _ => { + Opcode::Invalid + } + }; + let size_code = if size == 0b11 { + SizeCode::X + } else { + SizeCode::W + }; + + self.operands = [ + Operand::Register(size_code, Rt), + Operand::RegOffset(Rn, 0), + Operand::Nothing, + Operand::Nothing, + ]; + }, + 0b01000 | + 0b01001 => { + // load register (literal) + // V == 0 + let opc = (word >> 29) & 0x3; + let Rt = (word & 0x1f) as u16; + let imm19 = (word >> 5) & 0x7fff; + + let size = match opc { + 0b00 => { + self.opcode = Opcode::LDR; + SizeCode::W + }, + 0b01 => { + self.opcode = Opcode::LDR; + SizeCode::X + } + 0b10 => { + self.opcode = Opcode::LDRSW; + SizeCode::X + } + 0b11 => { + unreachable!("PRFM is not supported"); + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rt), + Operand::PCOffset(imm19), + Operand::Nothing, + Operand::Nothing, + ]; + }, + 0b01100 | + 0b01101 => { + // load register (literal) + // V == 1 + let opc = (word >> 29) & 0x3; + let Rt = word & 0x1f; + let imm19 = (word >> 5) & 0x7fff; + panic!("C3.3.5 V==1"); + }, + 0b10000 => { + // load/store no-allocate pair (offset) + // V == 0 + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + panic!("C3.3.7 V==0"); + }, + 0b10100 => { + // load/store no-allocate pair (offset) + // V == 1 + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + panic!("C3.3.7 V==1"); + }, + 0b10001 => { + // load/store register pair (post-indexed) + // V == 0 + let Rt = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let Rt2 = ((word >> 10) & 0x1f) as u16; + let mut imm7 = (((((word >> 15) & 0x7f) as i16) << 9) >> 9); + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + let size = match opc_L { + 0b000 => { + self.opcode = Opcode::STP; + imm7 <<= 2; + SizeCode::W + }, + 0b001 => { + self.opcode = Opcode::LDP; + imm7 <<= 2; + SizeCode::W + }, + 0b010 => { + self.opcode = Opcode::Invalid; + SizeCode::W + }, + 0b011 => { + self.opcode = Opcode::LDPSW; + imm7 <<= 2; + SizeCode::W + }, + 0b100 => { + self.opcode = Opcode::STP; + imm7 <<= 3; + SizeCode::X + }, + 0b101 => { + self.opcode = Opcode::LDP; + imm7 <<= 3; + SizeCode::X + }, + 0b110 | + 0b111 => { + self.opcode = Opcode::Invalid; + SizeCode::X + } + _ => { unreachable!(); } + }; + self.operands = [ + Operand::Register(size, Rt), + Operand::Register(size, Rt2), + Operand::RegPostIndex(Rn, imm7), + Operand::Nothing + ]; + }, + 0b10101 => { + // load/store register pair (post-indexed) + // V == 1 + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + panic!("C3.3.15 V==1"); + }, + 0b10010 => { + // load/store register pair (offset) + // V == 0 + let Rt = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let Rt2 = ((word >> 10) & 0x1f) as u16; + let mut imm7 = (((((word >> 15) & 0x7f) as i16) << 9) >> 9); + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + let size = match opc_L { + 0b000 => { + self.opcode = Opcode::STP; + imm7 <<= 2; + SizeCode::W + }, + 0b001 => { + self.opcode = Opcode::LDP; + imm7 <<= 2; + SizeCode::W + }, + 0b010 => { + self.opcode = Opcode::Invalid; + SizeCode::W + }, + 0b011 => { + self.opcode = Opcode::LDPSW; + imm7 <<= 2; + SizeCode::W + }, + 0b100 => { + self.opcode = Opcode::STP; + imm7 <<= 3; + SizeCode::X + }, + 0b101 => { + self.opcode = Opcode::LDP; + imm7 <<= 3; + SizeCode::X + }, + 0b110 | + 0b111 => { + self.opcode = Opcode::Invalid; + SizeCode::X + } + _ => { unreachable!(); } + }; + self.operands = [ + Operand::Register(size, Rt), + Operand::Register(size, Rt2), + Operand::RegOffset(Rn, imm7), + Operand::Nothing + ]; + }, + 0b10110 => { + // load/store register pair (offset) + // V == 1 + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + panic!("C3.3.14 V==1"); + }, + 0b10011 => { + // load/store register pair (pre-indexed) + // V == 0 + let Rt = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let Rt2 = ((word >> 10) & 0x1f) as u16; + let mut imm7 = (((((word >> 15) & 0x7f) as i16) << 9) >> 9); + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + let size = match opc_L { + 0b000 => { + self.opcode = Opcode::STP; + imm7 <<= 2; + SizeCode::W + }, + 0b001 => { + self.opcode = Opcode::LDP; + imm7 <<= 2; + SizeCode::W + }, + 0b010 => { + self.opcode = Opcode::Invalid; + SizeCode::W + }, + 0b011 => { + self.opcode = Opcode::LDPSW; + imm7 <<= 2; + SizeCode::W + }, + 0b100 => { + self.opcode = Opcode::STP; + imm7 <<= 3; + SizeCode::X + }, + 0b101 => { + self.opcode = Opcode::LDP; + imm7 <<= 3; + SizeCode::X + }, + 0b110 | + 0b111 => { + self.opcode = Opcode::Invalid; + SizeCode::X + } + _ => { unreachable!(); } + }; + self.operands = [ + Operand::Register(size, Rt), + Operand::Register(size, Rt2), + Operand::RegPreIndex(Rn, imm7), + Operand::Nothing + ]; + }, + 0b10111 => { + // load/store register pair (pre-indexed) + // V == 1 + let opc_L = ((word >> 22) & 1) | ((word >> 29) & 0x6); + panic!("C3.3.16 V==1"); + }, + 0b11000 | + 0b11001 => { + /* + * load/store register {unscaled immediate, immediate post-indexed, + * unprivileged, immediate pre-indexd, register offset} + * V == 0 + */ + let Rt = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let size_opc = ((word >> 22) & 0x03) | ((word >> 28) & 0x0c); + let category = (word >> 10) & 0x03; + println!("load/store: size_opc: {:#b}, category: {:#b}", size_opc, category); + if word & 0x200000 != 0 { + if category != 0b10 { + self.opcode = Opcode::Invalid; + return Some(()); + } else { + // Load/store register (register offset) + // C3.3.10 + let size = match size_opc { + 0b0000 => { + self.opcode = Opcode::STRB; + SizeCode::W + }, + 0b0001 => { + self.opcode = Opcode::LDRB; + SizeCode::W + }, + 0b0010 => { + self.opcode = Opcode::LDRSB; + SizeCode::X + }, + 0b0011 => { + self.opcode = Opcode::LDRSB; + SizeCode::W + }, + 0b0100 => { + self.opcode = Opcode::STRH; + SizeCode::W + }, + 0b0101 => { + self.opcode = Opcode::LDRH; + SizeCode::W + }, + 0b0110 => { + self.opcode = Opcode::LDRSH; + SizeCode::X + }, + 0b0111 => { + self.opcode = Opcode::LDRSH; + SizeCode::W + }, + 0b1000 => { + self.opcode = Opcode::STR; + SizeCode::W + }, + 0b1001 => { + self.opcode = Opcode::LDR; + SizeCode::W + }, + 0b1010 => { + self.opcode = Opcode::LDRSW; + SizeCode::X + }, + 0b1011 => { + self.opcode = Opcode::Invalid; + SizeCode::X + }, + 0b1100 => { + self.opcode = Opcode::STR; + SizeCode::X + }, + 0b1101 => { + self.opcode = Opcode::LDR; + SizeCode::X + }, + 0b1110 => { + panic!("PRFM is not supported yet"); +// self.opcode = Opcode::PRFM; +// SizeCode::X + }, + 0b1111 => { + self.opcode = Opcode::Invalid; + SizeCode::X + }, + _ => { unreachable!(); } + }; + + let S = ((word >> 12) & 0x1) as u8; + let option = ((word >> 13) & 0x07) as u8; + let Rm = ((word >> 16) & 0x1f) as u16; + + let index_size = match option & 0x3 { + 0b00 | + 0b01 => { + self.opcode = Opcode::Invalid; + return Some(()); + }, + 0b10 => { SizeCode::W } + 0b11 => { SizeCode::X } + _ => { unreachable!(); } + }; + + let shift_style = match option { + 0b000 | + 0b001 => { + self.opcode = Opcode::Invalid; + return Some(()); + }, + 0b010 => { ShiftStyle::UXTW }, + 0b011 => { ShiftStyle::LSL }, + 0b100 | + 0b101 => { + self.opcode = Opcode::Invalid; + return Some(()); + }, + 0b110 => { ShiftStyle::SXTW }, + 0b111 => { ShiftStyle::SXTX }, + _ => { unreachable!(); } + }; + + self.operands = [ + Operand::Register(size, Rt), + Operand::RegRegOffset(Rn, index_size, Rm, shift_style, S), + Operand::Nothing, + Operand::Nothing, + ]; + } + } else { + let imm9 = ((((word >> 12) & 0x1ff) as i16) << 7) >> 7; + match category { + 0b00 => { + // Load/store register (unscaled immediate) + let size = match size_opc { + 0b0000 => { + self.opcode = Opcode::STURB; + SizeCode::W + } + 0b0001 => { + self.opcode = Opcode::LDURB; + SizeCode::W + } + 0b0010 => { + self.opcode = Opcode::LDURSB; + SizeCode::X + } + 0b0011 => { + self.opcode = Opcode::LDURSB; + SizeCode::W + } + 0b0100 => { + self.opcode = Opcode::STURH; + SizeCode::W + } + 0b0101 => { + self.opcode = Opcode::LDURH; + SizeCode::W + } + 0b0110 => { + self.opcode = Opcode::LDURSH; + SizeCode::X + } + 0b0111 => { + self.opcode = Opcode::LDURSH; + SizeCode::W + } + 0b1000 => { + self.opcode = Opcode::STUR; + SizeCode::W + } + 0b1001 => { + self.opcode = Opcode::LDUR; + SizeCode::W + } + 0b1010 => { + self.opcode = Opcode::LDURSW; + SizeCode::X + } + 0b1011 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + 0b1100 => { + self.opcode = Opcode::STUR; + SizeCode::X + } + 0b1101 => { + self.opcode = Opcode::LDUR; + SizeCode::X + } + 0b1110 => { + panic!("PRFUM not handled yet"); + }, + 0b1111 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rt), + Operand::RegOffset(Rn, imm9), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b10 => { + // Load/store register (unprivileged) + + let size = match size_opc { + 0b0000 => { + self.opcode = Opcode::STTRB; + SizeCode::W + } + 0b0001 => { + self.opcode = Opcode::LDTRB; + SizeCode::W + } + 0b0010 => { + self.opcode = Opcode::LDTRSB; + SizeCode::X + } + 0b0011 => { + self.opcode = Opcode::LDTRSB; + SizeCode::W + } + 0b0100 => { + self.opcode = Opcode::STTRH; + SizeCode::W + } + 0b0101 => { + self.opcode = Opcode::LDTRH; + SizeCode::W + } + 0b0110 => { + self.opcode = Opcode::LDTRSH; + SizeCode::X + } + 0b0111 => { + self.opcode = Opcode::LDTRSH; + SizeCode::W + } + 0b1000 => { + self.opcode = Opcode::STTR; + SizeCode::W + } + 0b1001 => { + self.opcode = Opcode::LDTR; + SizeCode::W + } + 0b1010 => { + self.opcode = Opcode::LDTRSW; + SizeCode::X + } + 0b1011 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + 0b1100 => { + self.opcode = Opcode::STTR; + SizeCode::X + } + 0b1101 => { + self.opcode = Opcode::LDTR; + SizeCode::X + } + 0b1110 | + 0b1111 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rt), + Operand::RegPreIndex(Rn, imm9), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b01 | + 0b11 => { + let size = match size_opc { + 0b0000 => { + self.opcode = Opcode::STRB; + SizeCode::W + }, + 0b0001 => { + self.opcode = Opcode::LDRB; + SizeCode::W + } + 0b0010 => { + self.opcode = Opcode::LDRSB; + SizeCode::X + } + 0b0011 => { + self.opcode = Opcode::LDRSB; + SizeCode::W + } + 0b0100 => { + self.opcode = Opcode::STRH; + SizeCode::W + } + 0b0101 => { + self.opcode = Opcode::LDRH; + SizeCode::W + } + 0b0110 => { + self.opcode = Opcode::LDRSH; + SizeCode::X + } + 0b0111 => { + self.opcode = Opcode::LDRSH; + SizeCode::W + } + 0b1000 => { + self.opcode = Opcode::STR; + SizeCode::W + } + 0b1001 => { + self.opcode = Opcode::LDR; + SizeCode::W + } + 0b1010 | + 0b1011 => { + self.opcode = Opcode::Invalid; + SizeCode::W + } + 0b1100 => { + self.opcode = Opcode::STR; + SizeCode::X + } + 0b1101 => { + self.opcode = Opcode::LDR; + SizeCode::X + } + 0b1110 | + 0b1111 => { + self.opcode = Opcode::Invalid; + SizeCode::X + } + _ => { + unreachable!(); + } + }; + + self.operands = [ + Operand::Register(size, Rt), + if category == 0b01 { + Operand::RegPostIndex(Rn, imm9) + } else { + Operand::RegPreIndex(Rn, imm9) + }, + Operand::Nothing, + Operand::Nothing, + ]; + }, + _ => { + unreachable!(); + } + } + } + } + 0b11100 | + 0b11101 => { + /* + * load/store register {unscaled immediate, immediate post-indexed, + * unprivileged, immediate pre-indexd, register offset} + * V == 1 + */ + } + 0b11010 | + 0b11011 => { + // load/store register (unsigned immediate) + // V == 0 + let Rt = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let imm12 = ((((word >> 10) as i16) & 0x0fff) << 4) >> 4; + let size_opc = ((word >> 22) & 0x3) | ((word >> 28) & 0xc); + match size_opc { + 0b0000 => { + self.opcode = Opcode::STRB; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0001 => { + self.opcode = Opcode::LDRB; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0010 => { + self.opcode = Opcode::LDRSB; + self.operands = [ + Operand::Register(SizeCode::X, Rt), + Operand::RegOffset(Rn, imm12), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0011 => { + self.opcode = Opcode::LDRSB; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0100 => { + self.opcode = Opcode::STRH; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12 << 1), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0101 => { + self.opcode = Opcode::LDRH; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12 << 1), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0110 => { + self.opcode = Opcode::LDRSH; + self.operands = [ + Operand::Register(SizeCode::X, Rt), + Operand::RegOffset(Rn, imm12 << 1), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b0111 => { + self.opcode = Opcode::LDRSH; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12 << 1), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b1000 => { + self.opcode = Opcode::STR; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12 << 2), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b1001 => { + self.opcode = Opcode::LDR; + self.operands = [ + Operand::Register(SizeCode::W, Rt), + Operand::RegOffset(Rn, imm12 << 2), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b1010 => { + self.opcode = Opcode::LDRSW; + self.operands = [ + Operand::Register(SizeCode::X, Rt), + Operand::RegOffset(Rn, imm12 << 2), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b1011 => { self.opcode = Opcode::Invalid; } + 0b1100 => { + self.opcode = Opcode::STR; + self.operands = [ + Operand::Register(SizeCode::X, Rt), + Operand::RegOffset(Rn, imm12 << 3), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b1101 => { + self.opcode = Opcode::LDR; + self.operands = [ + Operand::Register(SizeCode::X, Rt), + Operand::RegOffset(Rn, imm12 << 3), + Operand::Nothing, + Operand::Nothing, + ]; + } + 0b1110 => { + unreachable!("PRFM not yet supported"); + } + 0b1111 => { self.opcode = Opcode::Invalid; } + _ => { unreachable!(); } + } + }, + 0b11110 | + 0b11111 => { + // load/store register (unsigned immediate) + // V == 1 + }, + 0b00100 => { + // AdvSIMD load/store multiple structures + }, + 0b00101 => { + // AdvSIMD load/store multiple structures (post-indexed) + }, + 0b00110 => { + // AdvSIMD load/store single structure + }, + 0b00111 => { + // AdvSIMD load/store single structure (post-indexed) + } + _ => { + self.opcode = Opcode::Invalid; + } + } + }, + Section::BranchExceptionSystem => { + let group_bits = ((word >> 29) << 2) | ((word >> 24) & 0x03); + match group_bits { + 0b00000 | + 0b00001 | + 0b00010 | + 0b00011 => { // unconditional branch (imm) + self.opcode = Opcode::B; + self.operands = [ + Operand::Offset((word & 0x01ffffff) << 2), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b00100 => { // compare branch (imm) + self.opcode = Opcode::CBZ; + let imm = (word >> 3) & 0x001ffffc; + let Rt = word & 0x1f; + self.operands = [ + Operand::Register(SizeCode::W, Rt as u16), + Operand::Offset(imm), + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b00101 => { // compare branch (imm) + self.opcode = Opcode::CBNZ; + let imm = (word >> 3) & 0x001ffffc; + let Rt = word & 0x1f; + self.operands = [ + Operand::Register(SizeCode::W, Rt as u16), + Operand::Offset(imm), + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b00110 => { // test branch (imm) + let imm = (word >> 3) & 0x0003fffc; + let b = (word >> 19) & 0x1f; + let Rt = word & 0x1f; + self.opcode = Opcode::TBZ; + self.operands = [ + Operand::Register(SizeCode::W, Rt as u16), + Operand::Imm16(b as u16), + Operand::Offset(imm), + Operand::Nothing + ]; + }, + 0b00111 => { // test branch (imm) + let imm = (word >> 3) & 0x0003fffc; + let b = (word >> 19) & 0x1f; + let Rt = word & 0x1f; + self.opcode = Opcode::TBNZ; + self.operands = [ + Operand::Register(SizeCode::W, Rt as u16), + Operand::Imm16(b as u16), + Operand::Offset(imm), + Operand::Nothing + ]; + }, + 0b01000 => { // conditional branch (imm) + let imm = (word >> 3) & 0x001ffffc; + let cond = word & 0x0f; + self.opcode = Opcode::Bcc(cond as u8); + self.operands = [ + Operand::Offset(imm), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + } + 0b01001 => { // conditional branch (imm) + self.opcode = Opcode::Invalid; + } + /* 0b01010 to 0b01111 seem all invalid? */ + 0b10000 | + 0b10001 | + 0b10010 | + 0b10011 => { // unconditional branch (imm) + self.opcode = Opcode::BL; + self.operands = [ + Operand::Offset((word & 0x01ffffff) << 2), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b10100 => { // compare branch (imm) + self.opcode = Opcode::CBZ; + let imm = (word >> 3) & 0x001ffffc; + let Rt = word & 0x1f; + self.operands = [ + Operand::Register(SizeCode::X, Rt as u16), + Operand::Offset(imm), + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b10101 => { // compare branch (imm) + self.opcode = Opcode::CBNZ; + let imm = (word >> 3) & 0x001ffffc; + let Rt = word & 0x1f; + self.operands = [ + Operand::Register(SizeCode::X, Rt as u16), + Operand::Offset(imm), + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b10110 => { // test branch (imm) + let imm = (word >> 3) & 0x0003fffc; + let b = (word >> 19) & 0x1f; + let Rt = word & 0x1f; + self.opcode = Opcode::TBZ; + self.operands = [ + Operand::Register(SizeCode::X, Rt as u16), + Operand::Imm16((b as u16) | 0x20), + Operand::Offset(imm), + Operand::Nothing + ]; + }, + 0b10111 => { // test branch (imm) + let imm = (word >> 3) & 0x0003fffc; + let b = (word >> 19) & 0x1f; + let Rt = word & 0x1f; + self.opcode = Opcode::TBNZ; + self.operands = [ + Operand::Register(SizeCode::X, Rt as u16), + Operand::Imm16((b as u16) | 0x20), + Operand::Offset(imm), + Operand::Nothing + ]; + }, + 0b11000 => { // exception generation + let ll = word & 0x3; + let op2 = (word >> 2) & 0x7; + let opc = (word >> 21) & 0x7; + match (opc, op2, ll) { + (0b000, 0b000, 0b01) => { + self.opcode = Opcode::SVC; + } + (0b000, 0b000, 0b10) => { + self.opcode = Opcode::HVC; + } + (0b000, 0b000, 0b11) => { + self.opcode = Opcode::SMC; + } + (0b001, 0b000, 0b00) => { + self.opcode = Opcode::BRK; + } + (0b010, 0b000, 0b00) => { + self.opcode = Opcode::HLT; + } + (0b101, 0b000, 0b01) => { + self.opcode = Opcode::DCPS1; + } + (0b101, 0b000, 0b10) => { + self.opcode = Opcode::DCPS2; + } + (0b101, 0b000, 0b11) => { + self.opcode = Opcode::DCPS3; + } + _ => { + self.opcode = Opcode::Invalid; + } + } + let imm = (word >> 5) & 0xffff; + self.operands = [ + Operand::Imm16(imm as u16), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + }, + 0b11001 => { // system + let remainder = word & 0xffffff; + if remainder >= 0x400000 { + self.opcode = Opcode::Invalid; + } else { + let Rt = word & 0x1f; + let Lop0 = ((word >> 19) & 0x7) as u8; + match Lop0 { + 0b000 => { + // MSR, HINT, CLREX, DSB, DMB, ISB + if Rt == 0b11111 { + let CRn = (word >> 12) & 0xf; + let op1 = (word >> 16) & 0x7; + let op2 = (word >> 5) & 0x1f; + + match CRn { + 0b0010 => { + if op1 == 0b011 { + self.opcode = Opcode::HINT(op2 as u8); + } else { + self.opcode = Opcode::Invalid; + } + }, + 0b0011 => { + match op2 { + 0b010 => { + self.opcode = Opcode::CLREX; + }, + 0b100 => { + self.opcode = Opcode::DSB; + }, + 0b101 => { + self.opcode = Opcode::DMB; + }, + 0b110 => { + self.opcode = Opcode::ISB; + } + _ => { + self.opcode = Opcode::Invalid; + } + }; + }, + 0b0100 => { + self.opcode = Opcode::MSRa(op1 as u8, op2 as u8); + self.operands[0] = Operand::Imm16( + ((word >> 8) & 0xf) as u16 + ); + } + _ => { + self.opcode = Opcode::Invalid; + } + } + } else { + self.opcode = Opcode::Invalid; + } + } + 0b001 => { + self.opcode = Opcode::SYS; + panic!("TODO"); + } + 0b010 | + 0b011 => { + self.opcode = Opcode::MSRb(word & 0x0fffff); + } + 0b100 => { + self.opcode = Opcode::Invalid; + } + 0b101 => { + self.opcode = Opcode::SYSL; + panic!("TODO"); + } + 0b110 | + 0b111 => { + self.opcode = Opcode::MRS(word & 0x0fffff); + } + _ => { + self.opcode = Opcode::Invalid; + } + } + } + }, + 0b11010 => { // unconditional branch (reg) + // actually the low 3 bits of opc + let opc = (word >> 21) & 0x7; + match opc { + 0b000 => { + if (word & 0x1ffc1f) == 0x1f0000 { + let Rn = (word >> 5) & 0x1f; + self.opcode = Opcode::BR; + self.operands = [ + Operand::Register(SizeCode::X, Rn as u16), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + } else { + self.opcode = Opcode::Invalid; + } + }, + 0b001 => { + if (word & 0x1ffc1f) == 0x1f0000 { + let Rn = (word >> 5) & 0x1f; + self.opcode = Opcode::BLR; + self.operands = [ + Operand::Register(SizeCode::X, Rn as u16), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + } else { + self.opcode = Opcode::Invalid; + } + }, + 0b010 => { + if (word & 0x1ffc1f) == 0x1f0000 { + let Rn = (word >> 5) & 0x1f; + self.opcode = Opcode::RET; + self.operands = [ + Operand::Register(SizeCode::X, Rn as u16), + Operand::Nothing, + Operand::Nothing, + Operand::Nothing + ]; + } else { + self.opcode = Opcode::Invalid; + } + }, + 0b100 => { + if (word & 0x1fffff) == 0x1f03e0 { + self.opcode = Opcode::ERET; + } else { + self.opcode = Opcode::Invalid; + } + }, + 0b101 => { + if (word & 0x1fffff) == 0x1f03e0 { + self.opcode = Opcode::DRPS; + } else { + self.opcode = Opcode::Invalid; + } + }, + _ => { + self.opcode = Opcode::Invalid; + } + } + } + 0b11011 => { // unconditional branch (reg) + // the last 1 is bit 24, which C3.2.7 indicates are + // all invalid encodings (opc is b0101 or lower) + self.opcode = Opcode::Invalid; + } + _ => { + // TODO: invalid + panic!("Illegal instruction"); + } + } + }, + }; + + Some(()) + } +} |