diff options
| author | iximeow <me@iximeow.net> | 2022-12-03 14:12:38 -0800 |
|---|---|---|
| committer | iximeow <me@iximeow.net> | 2022-12-03 14:12:38 -0800 |
| commit | c549f10115e727a6c0694e1ca59704826910e165 (patch) | |
| tree | a3b28df742c53fee8a2a370b282ed7fdaf6390eb | |
| parent | 091f1d66ef853d6339a96e43d71c137ee7d3907a (diff) | |
apply 2444de11 to 16-bit and 32-bit decoders
these don't need the extra `rex`-supporting index space, so they don't
have it.
| -rw-r--r-- | src/protected_mode/mod.rs | 15 | ||||
| -rw-r--r-- | src/real_mode/mod.rs | 15 |
2 files changed, 18 insertions, 12 deletions
diff --git a/src/protected_mode/mod.rs b/src/protected_mode/mod.rs index 5457b9d..71ddf37 100644 --- a/src/protected_mode/mod.rs +++ b/src/protected_mode/mod.rs @@ -6087,12 +6087,15 @@ fn read_M< #[inline] fn width_to_gp_reg_bank(width: u8) -> RegisterBank { - match width { - 1 => return RegisterBank::B, - 2 => return RegisterBank::W, - 4 => return RegisterBank::D, - _ => unsafe { unreachable_unchecked(); } - } + let index = width.trailing_zeros(); + + const BANK_LUT: [RegisterBank; 3] = [ + RegisterBank::B, + RegisterBank::W, + RegisterBank::D, + ]; + + *BANK_LUT.get(index as usize).unwrap_or_else(|| unsafe { unreachable_unchecked() }) } fn read_0f_opcode(opcode: u8, prefixes: &mut Prefixes) -> OpcodeRecord { diff --git a/src/real_mode/mod.rs b/src/real_mode/mod.rs index 8749ae2..bff00ad 100644 --- a/src/real_mode/mod.rs +++ b/src/real_mode/mod.rs @@ -6089,12 +6089,15 @@ fn read_M< #[inline] fn width_to_gp_reg_bank(width: u8) -> RegisterBank { - match width { - 1 => return RegisterBank::B, - 2 => return RegisterBank::W, - 4 => return RegisterBank::D, - _ => unsafe { unreachable_unchecked(); } - } + let index = width.trailing_zeros(); + + const BANK_LUT: [RegisterBank; 3] = [ + RegisterBank::B, + RegisterBank::W, + RegisterBank::D, + ]; + + *BANK_LUT.get(index as usize).unwrap_or_else(|| unsafe { unreachable_unchecked() }) } fn read_0f_opcode(opcode: u8, prefixes: &mut Prefixes) -> OpcodeRecord { |