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tavianator
525 days ago
SHL suffers from the same latency issue as SHLX it turns out
1 comments
loeg
525 days ago
SAL as well? (And anyway this example seems to be shifting by the low 8 bits of RCX (CL), not the full width register.)
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tavianator
525 days ago
SAL and SHL are synonyms, they have the same encoding. SHL only accepts CL as the count register, there's no other form that takes a variable shift count
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loeg
525 days ago
Ahh, thanks, I didn't make that connection.
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Bulat_Ziganshin
524 days ago
Intel shifts anyway mask out higher bits of CL, this hurts sometimes e.g. when you need to shift by 1..64 bits
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