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feat(cpu): implement RRX for Barrel Shifter

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-01-17 14:19:40 -04:00
parent 85ffdf44f5
commit 483e149b32
1 changed files with 9 additions and 0 deletions
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9
src/cpu/arm/barrel_shifter.zig
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@ -91,3 +91,12 @@ pub fn rotateRight(comptime S: bool, cpsr: *CPSR, rm: u32, amount: u8) u32 {
return result;
}
pub fn rotateRightExtended(comptime S: bool, cpsr: *CPSR, rm: u32) u32 {
if (!S) std.debug.panic("[BarrelShifter] Turns out I don't know how RRX works", .{});
const carry: u32 = @boolToInt(cpsr.c.read());
cpsr.c.write(rm & 1 == 1);
return (carry << 31) | (rm >> 1);
}