[Bug target/112548] New: 5% exec time regression in 429.mcf on AMD zen4 CPU

[fkastl at suse dot cz via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112548

            Bug ID: 112548
           Summary: 5% exec time regression in 429.mcf on AMD zen4 CPU
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: fkastl at suse dot cz
  Target Milestone: ---
              Host: x86_64-linux
            Target: x86_64-linux

As seen here:

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=991.60.0

between commits

g:4ea36076d66eea0f (2023-11-02 02:54)

and

g:c3847ca0571e5ace (2023-11-03 03:35)

there's about 5% slowdown.

The test is compiled with -Ofast -march=native -mtune=native lto and pgo. It is
run on an amd zen4 machine.