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thumb: Change ordering when decoding thumb instruction.

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This fixes a bug where "swi" instructions are decoded as conditional
branches.

The order really matters here, because Swi instructions are actually
conditional branch with illegal condition code.


Former-commit-id: 0024a8b53386a510dd321c157391c99a2af29223
This commit is contained in:
Michel Heily 2019-07-22 00:25:26 +03:00
parent 387e26fad9
commit eea26d2393
1 changed files with 3 additions and 3 deletions
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6
src/core/arm7tdmi/thumb/mod.rs
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@ -124,10 +124,10 @@ impl InstructionDecoder for ThumbInstruction {
Ok(PushPop) Ok(PushPop)
} else if raw & 0xf000 == 0xc000 { } else if raw & 0xf000 == 0xc000 {
Ok(LdmStm) Ok(LdmStm)
} else if raw & 0xf000 == 0xd000 {
Ok(BranchConditional)
} else if raw & 0xff00 == 0xdf00 { } else if raw & 0xff00 == 0xdf00 {
Ok(Swi) Ok(Swi)
} else if raw & 0xf000 == 0xd000 {
Ok(BranchConditional)
} else if raw & 0xf800 == 0xe000 { } else if raw & 0xf800 == 0xe000 {
Ok(Branch) Ok(Branch)
} else if raw & 0xf000 == 0xf000 { } else if raw & 0xf000 == 0xf000 {
@ -323,7 +323,7 @@ impl ThumbInstruction {
} }
pub fn cond(&self) -> ArmCond { pub fn cond(&self) -> ArmCond {
ArmCond::from_u8(self.raw.bit_range(8..12) as u8).unwrap() ArmCond::from_u8(self.raw.bit_range(8..12) as u8).expect("bad condition")
} }
pub fn flag(&self, bit: usize) -> bool { pub fn flag(&self, bit: usize) -> bool {