https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101185
H.J. Lu <hjl.tools at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |hjl.tools at gmail dot com
Keywords| |patch
Ever confirmed|0 |1
Last reconfirmed| |2021-06-24
Status|UNCONFIRMED |NEW
--- Comment #13 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Richard Biener from comment #12)
> (In reply to Hongtao.liu from comment #7)
> > The key point here is cpuid check function should not be compiled with
> > -mavx512vl or -mavx512bw, rely on cost model or alloca order is not
> > all-inclusive.
>
> Yeah, it looks bogus to check for AVX512 in a function that has the ISA
> already enabled ...
This worked by accident, not by design. The cost of mask register is
orthogonal to this CPUID issue. CPUID check should be compiled with
__attribute__ ((target("general-regs-only"))):
https://gcc.gnu.org/pipermail/gcc-patches/2021-June/573616.html
