[Bug rtl-optimization/91838] [8/9 Regression] incorrect use of shr and shrx to shift by 64, missed optimization of vector shift

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91838

--- Comment #16 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So the testcase g++.dg/opt/pr91838.C depends on the out come of the discussion
at:
https://gcc.gnu.org/pipermail/gcc-patches/2023-June/620378.html

Which I think is saying this testcase is undefined really.