[Bug target/83252] Wrong code with "-march=skylake-avx512 -O3"

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83252

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
With newer SDE bisected fix to r255258.
I'll commit the testcase and mark as fixed.