https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84547
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|Suboptimal code for masked |Suboptimal code for int128 |shifts (ARM64) |masked shifts (ARM64) Last reconfirmed| |2021-04-17 Ever confirmed|0 |1 Status|UNCONFIRMED |NEW --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Yes int128 (or rather double wide register) shifts are not optimized that well. They are not used by many people even. I wonder if there is a way to use vector instructions to do them.