[Bug target/119270] New: [15 Regression] 5% slowdown of 507.cactuBSSN_r on Intel Ice Lake

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119270

            Bug ID: 119270
           Summary: [15 Regression] 5% slowdown of 507.cactuBSSN_r on
                    Intel Ice Lake
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pheeck at gcc dot gnu.org
            Blocks: 26163
  Target Milestone: ---
              Host: x86_64-linux
            Target: x86_64-linux

As seen here

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=800.437.0

there was a 5% exec time slowdown of the 507.cactuBSSN_r SPEC 2017 benchmark
between commits

r15-7920-g62a6a53766ba46
r15-7936-gc6b277f1dc6d11

when run with -O2 -march=generic -flto on an Intel Ice Lake (3rd generation
Xeon) machine.


Referenced Bugs:

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