[Bug tree-optimization/126790] New: [17 Regression] 9% slowdown of imagick_r on x86

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126790

            Bug ID: 126790
           Summary: [17 Regression] 9% slowdown of imagick_r on x86
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Keywords: missed-optimization, needs-bisection
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jmelcr at gcc dot gnu.org
            Blocks: 26163
  Target Milestone: ---
              Host: x86_64-suse-linux
            Target: x86_64-suse-linux
             Build: x86_64-suse-linux

As seen here

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=801.507.0

there was a 9% exec time slowdown of the imagick_r SPEC 2017 benchmark between
commits

r17-2606-g2c421a5cbe9d2b
r17-2674-g36f131b48e6a84

when compiled with -Ofast -march=native -g on an Intel Ice Lake (3rd generation
Xeon) machine.

This is a regression against GCC 16. See the comparison
here:

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=816.507.0&plot.1=848.507.0&plot.2=832.507.0&plot.3=911.507.0&plot.4=1093.507.0&plot.5=1200.507.0&plot.6=1496.507.0&plot.7=801.507.0&;


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)