[Bug target/125542] New: [17 Regression] 5% slowdown of calculix on Aarch64

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125542

            Bug ID: 125542
           Summary: [17 Regression] 5% slowdown of calculix on Aarch64
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Keywords: missed-optimization, needs-bisection
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jmelcr at gcc dot gnu.org
            Blocks: 26163
  Target Milestone: ---
              Host: aarch64-suse-linux
            Target: aarch64-suse-linux
             Build: aarch64-suse-linux

As seen here

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=578.170.0

there was a 5% exec time slowdown of the calculix SPEC 2006 benchmark between
commits

r17-206-gc31d01c3eaecfc
r17-344-g2dde6c91d0f0df

when compiled with -Ofast -march=native with PGO on an Ampere Altra Neoverse N1
machine.
This is a regression against previous GCC versions. See the comparison
here:

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=635.170.0&plot.1=676.170.0&plot.2=660.170.0&plot.3=650.170.0&plot.4=621.170.0&plot.5=597.170.0&plot.6=761.170.0&plot.7=874.170.0&plot.8=1066.170.0&plot.9=1236.170.0&plot.10=1528.170.0&plot.11=578.170.0&;


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=26163
[Bug 26163] [meta-bug] missed optimization in SPEC (2026, 2k17, 2k and 2k6 and
95)