[Bug target/118966] New: [15 Regression] 6% slowdown of 464.h264ref on Aarch64

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118966

            Bug ID: 118966
           Summary: [15 Regression] 6% slowdown of 464.h264ref on Aarch64
           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=578.220.0

there was a 6% exec time slowdown of the 464.h264ref SPEC 2006 benchmark
between commits

r15-7380-g198f4df07d6a1d
r15-7490-g3880271e94b759

when run with -Ofast -march=native PGO on an Ampere Altra Neoverse N1 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)