I agree with you. It should take the same time when thinking more about it. I remember learning this in ~2016 and I did performance test on Skylake which confirmed (Windows VS2015). I think I remember that i only tested with addsd/addss. Definitely not x87. But as always, if the result can not be reproduced... I stand corrected until then.
dosshell|1 year ago
[0] https://gist.github.com/dosshell/495680f0f768ae84a106eb054f2...
Sorry for the confusion and spreading false information.