diff options
Diffstat (limited to 'src/isa')
| -rw-r--r-- | src/isa/mod.rs | 15 | ||||
| -rw-r--r-- | src/isa/opcodes.rs | 2 |
2 files changed, 13 insertions, 4 deletions
diff --git a/src/isa/mod.rs b/src/isa/mod.rs index 0e3261b..c8aa290 100644 --- a/src/isa/mod.rs +++ b/src/isa/mod.rs @@ -127,9 +127,18 @@ impl Instruction { } pub fn s_imm(&self) -> i32 { - let word = self.word as i32; - let low = (word >> 7) & 0x1F; - let high = (word >> 25) & 0x7F; + let low = (self.word >> 7) & 0x1F; + let high = ((self.word as i32) >> 25) & 0x7F; (high << 7) | low } + + pub fn uj_imm(&self) -> i32 { + // Want zero-extension + let low1 = (self.word >> 21) & 0x3FF; + let low11 = (self.word >> 19) & 0x1; + let low12 = (self.word >> 12) & 0xFF; + // Want sign-extension + let low20 = ((self.word as i32) >> 30) & 0x1; + (low20 << 20) | (low12 << 12) | (low11 << 11) | (low1 << 1) + } } diff --git a/src/isa/opcodes.rs b/src/isa/opcodes.rs index e5763e3..56b9568 100644 --- a/src/isa/opcodes.rs +++ b/src/isa/opcodes.rs @@ -1,6 +1,6 @@ pub const BRANCH: u32 = 0x63; pub const JALR: u32 = 0x67; -pub const JAL: u32 = 0x68; +pub const JAL: u32 = 0x6F; pub const INTEGER_IMMEDIATE: u32 = 0x13; pub const INTEGER_REGISTER: u32 = 0x33; pub const LOAD: u32 = 0x3; |