From 93386de05f07ec55944fddc81b99de80c607a937 Mon Sep 17 00:00:00 2001 From: iximeow Date: Sun, 7 Nov 2021 13:19:05 -0800 Subject: floating point mov, several data processing ops, compare --- src/armv8/a64.rs | 518 ++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 517 insertions(+), 1 deletion(-) (limited to 'src/armv8') diff --git a/src/armv8/a64.rs b/src/armv8/a64.rs index da0df7c..534fc58 100644 --- a/src/armv8/a64.rs +++ b/src/armv8/a64.rs @@ -39,6 +39,15 @@ mod docs { assert_eq!(HighestSetBit(8, 0x08), 3); } + #[test] + fn test_vfpexpandimm() { + assert_eq!(VFPExpandImm(0x34), 20.0f64); + assert_eq!(VFPExpandImm(0x70), 1f64); + assert_eq!(VFPExpandImm(0xdc), -0.4375f64); + assert_eq!(VFPExpandImm(0xe0), -0.5f64); + assert_eq!(VFPExpandImm(0xf0), -1f64); + } + fn HighestSetBit(N: u8, bits: u64) -> u8 { let mut probe = 1u64 << (N - 1); let mut i = N - 1; @@ -132,6 +141,20 @@ mod docs { super::ShiftStyle::ROR, ][op as usize] } + + pub fn VFPExpandImm(imm8: u8) -> f64 { + let sign = imm8 >> 7; + let exp = imm8 >> 4; + let exp = (exp as i16) << 13 >> 13; + let exp = exp ^ 0b1_00_0000_0000; + let frac = (imm8 << 4); + + let bits = ((sign as u64) << 63) | + (((exp as u64) & 0b1_11_1111_1111) << 52) | + ((frac as u64) << 44); + + f64::from_bits(bits) + } } #[derive(Debug, PartialEq, Copy, Clone)] @@ -978,6 +1001,87 @@ impl Display for Instruction { Opcode::LD4 => { write!(fmt, "ld4")?; } + Opcode::FMADD => { + write!(fmt, "fmadd")?; + } + Opcode::FMSUB => { + write!(fmt, "fmsub")?; + } + Opcode::FNMADD => { + write!(fmt, "fnmadd")?; + } + Opcode::FNMSUB => { + write!(fmt, "fnmsub")?; + } + Opcode::SCVTF => { + write!(fmt, "scvtf")?; + } + Opcode::UCVTF => { + write!(fmt, "ucvtf")?; + } + Opcode::FCVTZS => { + write!(fmt, "fcvtzs")?; + } + Opcode::FCVTZU => { + write!(fmt, "fcvtzu")?; + } + Opcode::FMOV => { + write!(fmt, "fmov")?; + } + Opcode::FABS => { + write!(fmt, "fabs")?; + } + Opcode::FNEG => { + write!(fmt, "fneg")?; + } + Opcode::FSQRT => { + write!(fmt, "fsqrt")?; + } + Opcode::FRINTN => { + write!(fmt, "frintn")?; + } + Opcode::FRINTP => { + write!(fmt, "frintp")?; + } + Opcode::FRINTM => { + write!(fmt, "frintm")?; + } + Opcode::FRINTZ => { + write!(fmt, "frintz")?; + } + Opcode::FRINTA => { + write!(fmt, "frinta")?; + } + Opcode::FRINTX => { + write!(fmt, "frintx")?; + } + Opcode::FRINTI => { + write!(fmt, "frinti")?; + }, + Opcode::FRINT32Z => { + write!(fmt, "frint32z")?; + } + Opcode::FRINT32X => { + write!(fmt, "frint32x")?; + } + Opcode::FRINT64Z => { + write!(fmt, "frint64z")?; + } + Opcode::FRINT64X => { + write!(fmt, "frint64x")?; + } + Opcode::BFCVT => { + write!(fmt, "bfcvt")?; + } + Opcode::FCVT => { + write!(fmt, "fcvt")?; + } + Opcode::FCMP => { + write!(fmt, "fcmp")?; + } + Opcode::FCMPE => { + write!(fmt, "fcmpe")?; + } }; if self.operands[0] != Operand::Nothing { @@ -1189,6 +1293,33 @@ pub enum Opcode { LD2R, LD3R, LD4R, + FMADD, + FMSUB, + FNMADD, + FNMSUB, + SCVTF, + UCVTF, + FCVTZS, + FCVTZU, + FMOV, + FABS, + FNEG, + FSQRT, + FRINTN, + FRINTP, + FRINTM, + FRINTZ, + FRINTA, + FRINTX, + FRINTI, + FRINT32Z, + FRINT32X, + FRINT64Z, + FRINT64X, + BFCVT, + FCVT, + FCMP, + FCMPE, } #[derive(Copy, Clone, Debug, PartialEq)] @@ -1239,6 +1370,7 @@ pub enum Operand { Offset(i64), PCOffset(i64), Immediate(u32), + ImmediateDouble(f64), Imm64(u64), Imm16(u16), ImmShift(u16, u8), @@ -1377,6 +1509,9 @@ impl Display for Operand { Operand::Immediate(i) => { write!(fmt, "{:#x}", i) }, + Operand::ImmediateDouble(d) => { + write!(fmt, "{:}", d) + }, Operand::Imm16(i) => { write!(fmt, "{:#x}", *i) }, @@ -1522,7 +1657,388 @@ impl Decoder for InstDecoder { match section { Section::DataProcessingSimd | Section::DataProcessingSimd2 => { - return Err(DecodeError::IncompleteDecoder); + let op3 = (word >> 10) & 0b1_1111_1111; + let op2 = (word >> 19) & 0b1111; + let op1 = (word >> 23) & 0b11; + let op0 = (word >> 28) & 0b1111; + if (op0 & 0b0101) != 0b0001 { + // op0 != x0x1 + return Err(DecodeError::IncompleteDecoder); + } else { + // op0 == x0x1 (floating-point ops or unallocated - op1, op2, op3 are + // self-contained from here) + if op1 & 0b10 == 0b00 { + if op2 & 0b0100 == 0b0000 { + // op2 = x0xx + // `Conversion between floating-point and fixed-point` + let sf = (word >> 31); + let S = (word >> 29) & 1; + let ty = (word >> 22) & 0b11; + let mode = (word >> 19) & 0b11; + let opcode = (word >> 16) & 0b111; + let scale = (word >> 10) & 0b11_1111; + let Rn = (word >> 5) & 0b1_1111; + let Rd = word & 0b1_1111; + + if S == 1 { + return Err(DecodeError::InvalidOpcode); + } + + if sf == 0 && scale >= 100000 { + return Err(DecodeError::InvalidOpcode); + } + + if opcode >= 0b100 { + return Err(DecodeError::InvalidOpcode); + } + + let rm_opcode = (mode << 2) | (opcode & 0b11); + + let size = if sf == 0 { + SizeCode::W + } else { + SizeCode::X + }; + + let precision = if ty == 0b00 { + SIMDSizeCode::S + } else if ty == 0b01 { + SIMDSizeCode::D + } else if ty == 0b11 { + SIMDSizeCode::H + } else { + return Err(DecodeError::InvalidOperand); + }; + + const OPCODES: &[Result] = &[ + // type = 00 + // mode = 00, opcode = 00 + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + // mode = 00, opcode = 10 + Ok(Opcode::SCVTF), + Ok(Opcode::UCVTF), + // mode = 11, opcode = 00 + Ok(Opcode::FCVTZS), + Ok(Opcode::FCVTZU), + // mode = 11, opcode = 10 + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + ]; + + let opc_idx = ((mode & 0b10) << 1) | (opcode & 0b011); + inst.opcode = OPCODES[opc_idx as usize]?; + + if mode == 0b00 { + inst.operands = [ + Operand::SIMDRegister(precision, Rd as u16), + Operand::Register(size, Rn as u16), + Operand::Immediate(std::cmp::min(64 - scale, if size == SizeCode::X { 64 } else { 32 })), + Operand::Nothing, + ]; + } else { + inst.operands = [ + Operand::Register(size, Rd as u16), + Operand::SIMDRegister(precision, Rn as u16), + Operand::Immediate(std::cmp::min(64 - scale, if size == SizeCode::X { 64 } else { 32 })), + Operand::Nothing, + ]; + } + return Err(DecodeError::IncompleteDecoder); + } else if (op3 & 0b000_111111) == 0b000_000000 { + // op2 = x1xx, op3 = xxx000000 + let sf = (word >> 31); + let S = (word >> 29) & 1; + let ty = (word >> 22) & 0b11; + let mode = (word >> 19) & 0b11; + let opcode = (word >> 16) & 0b111; + let Rn = (word >> 5) & 0b1_1111; + let Rd = word & 0b1_1111; + + if S == 1 { + return Err(DecodeError::InvalidOpcode); + } + + if opcode >= 0b100 { + return Err(DecodeError::InvalidOpcode); + } + + let rm_opcode = (mode << 2) | (opcode & 0b11); + + let size = if sf == 0 { + SizeCode::W + } else { + SizeCode::X + }; + + let precision = if ty == 0b00 { + SIMDSizeCode::S + } else if ty == 0b01 { + SIMDSizeCode::D + } else if ty == 0b11 { + SIMDSizeCode::H + } else { + return Err(DecodeError::InvalidOperand); + }; + + const OPCODES: &[Result] = &[ + // type = 00 + // mode = 00, opcode = 00 + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + // mode = 00, opcode = 10 + Ok(Opcode::SCVTF), + Ok(Opcode::UCVTF), + // mode = 11, opcode = 00 + Ok(Opcode::FCVTZS), + Ok(Opcode::FCVTZU), + // mode = 11, opcode = 10 + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + ]; + + let opc_idx = ((mode & 0b10) << 1) | (opcode & 0b011); + inst.opcode = OPCODES[opc_idx as usize]?; + + if mode == 0b00 { + inst.operands = [ + Operand::SIMDRegister(precision, Rd as u16), + Operand::Register(size, Rn as u16), + Operand::Nothing, + Operand::Nothing, + ]; + } else { + inst.operands = [ + Operand::Register(size, Rd as u16), + Operand::SIMDRegister(precision, Rn as u16), + Operand::Nothing, + Operand::Nothing, + ]; + } + } else { + if (word >> 29) > 0 { + // if either `M` or `S` are set.. + return Err(DecodeError::InvalidOpcode); + } + match op3.trailing_zeros() { + 0 => { + // op3 = xxxxxxxx1 + // `Floating-point conditional compare` or + // `Floating-point conditional select` + } + 1 => { + // op3 = xxxxxxx10 + // `Floating-point data-processing (2 source)` + } + 2 => { + // op3 = xxxxxx100 + // `Floating-point immediate` + let ty = (word >> 22) & 0b11; + let imm8 = (word >> 13) & 0b1111_1111; + let imm5 = (word >> 5) & 0b1_1111; + let Rd = word & 0b1_1111; + + if imm5 != 0 { + return Err(DecodeError::InvalidOpcode); + } + + let precision = if ty == 0b00 { + SIMDSizeCode::S + } else if ty == 0b01 { + SIMDSizeCode::D + } else if ty == 0b11 { + SIMDSizeCode::H + } else { + return Err(DecodeError::InvalidOperand); + }; + + inst.opcode = Opcode::FMOV; + inst.operands = [ + Operand::SIMDRegister(precision, Rd as u16), + Operand::ImmediateDouble(docs::VFPExpandImm(imm8 as u8)), + Operand::Nothing, + Operand::Nothing, + ]; + } + 3 => { + // op3 = xxxxx1000 + // `Floating-point compare` + let ty = (word >> 22) & 0b11; + let Rm = (word >> 16) & 0b1_1111; + let opcode = (word >> 14) & 0b11; + let Rn = (word >> 5) & 0b1_1111; + let opcode2 = word & 0b1_1111; + + if (opcode & 0b00_111) != 00_000 { + // any of the low three bits in opcode being set means + // unallocated + return Err(DecodeError::InvalidOpcode); + } + + let precision = if ty == 0b00 { + SIMDSizeCode::S + } else if ty == 0b01 { + SIMDSizeCode::D + } else if ty == 0b11 { + SIMDSizeCode::H + } else { + return Err(DecodeError::InvalidOperand); + }; + + inst.opcode = if opcode & 0b1_0000 != 0 { + Opcode::FCMPE + } else { + Opcode::FCMP + }; + inst.operands = [ + Operand::SIMDRegister(precision, Rn as u16), + if Rm == 0 { + Operand::Immediate(0) + } else { + Operand::SIMDRegister(precision, Rm as u16) + }, + Operand::Nothing, + Operand::Nothing, + ]; + } + 4 => { + // op3 = xxxx10000 + // `Floating-point data-processing (1 source)` + let ty = (word >> 22) & 0b11; + let opcode = (word >> 15) & 0b111_111; + let Rn = (word >> 5) & 0b1_1111; + let Rd = word & 0b1_1111; + + if opcode >= 0b100_000 { + return Err(DecodeError::InvalidOpcode); + } + + let precision = if ty == 0b00 { + SIMDSizeCode::S + } else if ty == 0b01 { + SIMDSizeCode::D + } else if ty == 0b11 { + SIMDSizeCode::H + } else { + return Err(DecodeError::InvalidOperand); + }; + + const OPCODES: &[Result] = &[ + Ok(Opcode::FMOV), Ok(Opcode::FABS), Ok(Opcode::FNEG), Ok(Opcode::FSQRT), + Err(DecodeError::InvalidOpcode), Err(DecodeError::InvalidOpcode), Err(DecodeError::InvalidOpcode), Err(DecodeError::InvalidOpcode), + Ok(Opcode::FRINTN), Ok(Opcode::FRINTP), Ok(Opcode::FRINTM), Ok(Opcode::FRINTZ), + Ok(Opcode::FRINTA), Err(DecodeError::InvalidOpcode), Ok(Opcode::FRINTX), Ok(Opcode::FRINTI), + Ok(Opcode::FRINT32Z), Ok(Opcode::FRINT32X), Ok(Opcode::FRINT64Z), Ok(Opcode::FRINT64X), + ]; + + if opcode >= 0b000100 && opcode < 0b001000 { + // precision-specific opcodes to convert between floating + // point precisions + let dest_precision_bits = opcode & 0b11; + let dest_precision = if dest_precision_bits == 0b00 { + SIMDSizeCode::S + } else if dest_precision_bits == 0b01 { + SIMDSizeCode::D + } else if dest_precision_bits == 0b10 { + return if precision == SIMDSizeCode::H { + inst.opcode = Opcode::BFCVT; + inst.operands = [ + Operand::SIMDRegister(SIMDSizeCode::H, Rd as u16), + Operand::SIMDRegister(SIMDSizeCode::S, Rn as u16), + Operand::Nothing, + Operand::Nothing, + ]; + Ok(()) + } else { + Err(DecodeError::InvalidOpcode) + }; + } else { + SIMDSizeCode::H + }; + + if precision == dest_precision { + return Err(DecodeError::InvalidOpcode); + } + + inst.opcode = Opcode::FCVT; + inst.operands = [ + Operand::SIMDRegister(dest_precision, Rd as u16), + Operand::SIMDRegister(precision, Rn as u16), + Operand::Nothing, + Operand::Nothing, + ]; + } else { + let opc = OPCODES.get(opcode as usize).cloned().unwrap_or(Err(DecodeError::InvalidOpcode))?; + inst.opcode = opc; + inst.operands = [ + Operand::SIMDRegister(precision, Rd as u16), + Operand::SIMDRegister(precision, Rn as u16), + Operand::Nothing, + Operand::Nothing, + ]; + } + } + 5 => { + // op3 = xxx100000 + // unallocated + return Err(DecodeError::InvalidOpcode); + } + _ => { + // 6 or more zeroes + // op3 = xxx000000 + // `Conversion between floating-point and integer` + // handled above, so this arm is actually unreachable. + } + } + } + } else { + // op1 = 1x + // `Floating-point data-processing (3 source)` + + if (word >> 29) > 0 { + // if either `M` or `S` are set.. + return Err(DecodeError::InvalidOpcode); + } + + let type_o1_o0 = ((word >> 20) & 0b1110) | ((word >> 15) & 0b0001); + const OPCODES: [Result<(Opcode, SIMDSizeCode), DecodeError>; 16] = [ + Ok((Opcode::FMADD, SIMDSizeCode::S)), + Ok((Opcode::FMSUB, SIMDSizeCode::S)), + Ok((Opcode::FNMADD, SIMDSizeCode::S)), + Ok((Opcode::FNMSUB, SIMDSizeCode::S)), + + Ok((Opcode::FMADD, SIMDSizeCode::D)), + Ok((Opcode::FMSUB, SIMDSizeCode::D)), + Ok((Opcode::FNMADD, SIMDSizeCode::D)), + Ok((Opcode::FNMSUB, SIMDSizeCode::D)), + + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + Err(DecodeError::InvalidOpcode), + + Ok((Opcode::FMADD, SIMDSizeCode::H)), // TODO: half-precision added in ARMv8.2 + Ok((Opcode::FMSUB, SIMDSizeCode::H)), + Ok((Opcode::FNMADD, SIMDSizeCode::H)), + Ok((Opcode::FNMSUB, SIMDSizeCode::H)), + ]; + + let (opcode, precision) = OPCODES[type_o1_o0 as usize]?; + + let Rd = (word & 0x1f) as u16; + let Rn = ((word >> 5) & 0x1f) as u16; + let Ra = ((word >> 10) & 0x1f) as u16; + let Rm = ((word >> 16) & 0x1f) as u16; + + inst.opcode = opcode; + inst.operands = [ + Operand::SIMDRegister(precision, Rd), + Operand::SIMDRegister(precision, Rn), + Operand::SIMDRegister(precision, Rm), + Operand::SIMDRegister(precision, Ra), + ]; + } + } } Section::Unallocated => { inst.opcode = Opcode::Invalid; -- cgit v1.1