3 ms·
That is not the case. On a Skylake chip, a pushfd + popfd roundtrip costs 24 cycles.
by pbsd 8y ago
That is not the case. On a Skylake chip, a pushfd + popfd roundtrip costs 24 cycles.
- feikname 8y agoJust out of curiosity, how do you know this? Is it some kind of measurement you made yourself, written on Intel docs somewhere or something else? I've been wondering about how much instructions cost lately and would like to be able to know this without the need of asking others.
- pbsd 8y agoAgner's instruction listings [1] and InstLatX64 [2] are good sources for a variety of chips. The 24 cycle figure above can be seen at https://github.com/InstLatx64/InstLatx64/blob/ee13abcfb1e2bb8207737a362daa73d7c9ed66a8/GenuineIntel00506E3_Skylake2_InstLatX64.txt#L625-L628 https://github.com/InstLatx64/InstLatx64/blob/ee13abcfb1e2bb... [1] http://www.agner.org/optimize/#manuals http://www.agner.org/optimize/#manuals [2] https://github.com/InstLatx64 https://github.com/InstLatx64
- koverstreet 8y agoThere's also the intel optimization manuals.