5 ms·
SHL suffers from the same latency issue as SHLX it turns out
by tavianator 2y ago
SHL suffers from the same latency issue as SHLX it turns out
- loeg 2y agoSAL as well? (And anyway this example seems to be shifting by the low 8 bits of RCX (CL), not the full width register.)
- Bulat_Ziganshin 2y agoIntel shifts anyway mask out higher bits of CL, this hurts sometimes e.g. when you need to shift by 1..64 bits
- tavianator 2y agoSAL 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
- loeg 2y agoAhh, thanks, I didn't make that connection.