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

Re:XOR'ing a register with itself is the idiom for zeroing i... by tliltocatl on Wednesday April 22, 2026 @04:28AM (#47860701)
On superscalars running xor trick as is would be significantly slower because it implies a data dependency where there isn't one. But all OOO x86's optimize it away internally.
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Re:XOR'ing a register with itself is the idiom for zeroing i... by IshKebab on Thursday April 23, 2026 @02:34AM (#47872791)
Sub has the same false data dependency.
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