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A comment on XOR'ing a register with itself is the idiom for zeroing it out. Why not sub?.

Re:XOR'ing a register with itself is the idiom for zeroing i... by lochnessduck on Wednesday April 22, 2026 @03:49PM (#47868385)
I use the carry flag in a lot of z80 assembly for communicating a status of an operation. XOR doesn’t mess with the carry flag, I think it’s another point in favor of xor. (Though I don’t remember even considering using sub)
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Re:XOR'ing a register with itself is the idiom for zeroing i... by Jare on Wednesday April 22, 2026 @04:05PM (#47868585)
This is the exact reason I remember from back in the 80's. Perform arithmetic, clear register, CF is still valid.
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