From 56bc9a6d43b802efd338ea27180bfdfa6b4eeba7 Mon Sep 17 00:00:00 2001 From: iximeow Date: Sat, 8 Jul 2023 14:52:49 -0700 Subject: seems like this makes things a bit faster...? --- src/long_mode/mod.rs | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) (limited to 'src') diff --git a/src/long_mode/mod.rs b/src/long_mode/mod.rs index 3b2f23f..658f15c 100644 --- a/src/long_mode/mod.rs +++ b/src/long_mode/mod.rs @@ -5915,12 +5915,12 @@ fn read_modrm_reg< fn read_sib_disp< T: Reader<::Address, ::Word>, S: DescriptionSink, ->(instr: &Instruction, words: &mut T, modbits: u8, sibbyte: u8, sink: &mut S) -> Result { +>(instr: &Instruction, words: &mut T, modrm: u8, sibbyte: u8, sink: &mut S) -> Result { let sib_start = words.offset() as u32 * 8 - 8; let modbit_addr = words.offset() as u32 * 8 - 10; let disp_start = words.offset() as u32 * 8; - let disp = if modbits == 0b00 { + let disp = if modrm < 0b01_000_000 { // modbits == 0b00 if (sibbyte & 7) == 0b101 { sink.record(modbit_addr, modbit_addr + 1, InnerDescription::Misc("4-byte displacement").with_id(sib_start + 0)); @@ -5933,7 +5933,7 @@ fn read_sib_disp< } else { 0 } - } else if modbits == 0b01 { + } else if modrm < 0b10_000_000 { // modbits == 0b01 sink.record(modbit_addr, modbit_addr + 1, InnerDescription::Misc("1-byte displacement").with_id(sib_start + 0)); if instr.prefixes.evex().is_some() { @@ -5966,9 +5966,8 @@ fn read_sib< let modrm_start = words.offset() as u32 * 8 - 8; let sib_start = words.offset() as u32 * 8; - let modbits = modrm >> 6; let sibbyte = words.next().ok().ok_or(DecodeError::ExhaustedInput)?; - let disp = read_sib_disp(instr, words, modbits, sibbyte, sink)?; + let disp = read_sib_disp(instr, words, modrm, sibbyte, sink)?; instr.disp = disp as u32 as u64; let mut r = 0; @@ -6000,7 +5999,7 @@ fn read_sib< InnerDescription::Misc("iii + rex.x selects no index register") .with_id(sib_start + 0) ); - if modbits == 0b00 { + if modrm < 0b01_000_000 { sink.record( modrm_start + 6, modrm_start + 7, @@ -6024,7 +6023,7 @@ fn read_sib< InnerDescription::RegisterNumber("iii", instr.regs[2].num & 0b111, instr.regs[2]) .with_id(sib_start + 0) ); - if modbits == 0 { + if modrm < 0b01_000_000 { sink.record( modrm_start + 6, modrm_start + 7, @@ -6077,7 +6076,7 @@ fn read_sib< InnerDescription::Misc("iii + rex.x selects no index register") .with_id(sib_start + 0) ); - if modbits == 0b00 { + if modrm < 0b01_000_000 { sink.record( modrm_start + 6, modrm_start + 7, @@ -6101,7 +6100,7 @@ fn read_sib< InnerDescription::RegisterNumber("iii", instr.regs[2].num & 0b111, instr.regs[2]) .with_id(sib_start + 0) ); - if modbits == 0 { + if modrm < 0b01_000_000 { sink.record( modrm_start + 6, modrm_start + 7, @@ -6162,7 +6161,6 @@ fn read_M< >(words: &mut T, instr: &mut Instruction, modrm: u8, sink: &mut S) -> Result { let modrm_start = words.offset() as u32 * 8 - 8; - let modbits = modrm >> 6; let mmm = modrm & 7; let op_spec = if mmm == 4 { sink.record( @@ -6173,11 +6171,10 @@ fn read_M< ); return read_sib(words, instr, modrm, sink); } else { - let mut r = 0; + instr.regs[1].num = mmm; if instr.prefixes.rex_unchecked().b() { - r = 0b1000; + instr.regs[1].num |= 0b1000; } - instr.regs[1].num = r | mmm; sink.record( modrm_start, modrm_start + 2, @@ -6185,7 +6182,7 @@ fn read_M< .with_id(modrm_start + 2) ); - if modbits == 0b00 { + if modrm < 0b01_000_000 { // modbits == 0b00 if mmm == 5 { sink.record( modrm_start + 6, @@ -6242,7 +6239,7 @@ fn read_M< } } else { let disp_start = words.offset(); - let disp = if modbits == 0b01 { + let disp = if modrm < 0b10_000_000 { // modbits == 0b01 (not 0b00, as detected above) sink.record( modrm_start + 6, modrm_start + 7, -- cgit v1.1