[Bug target/122932] New: 5% slowdown of 505.mcf_r on Aarch64

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122932

            Bug ID: 122932
           Summary: 5% slowdown of 505.mcf_r on Aarch64
           Product: gcc
           Version: 16.0
            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
                CC: pheeck at gcc dot gnu.org
            Blocks: 26163
  Target Milestone: ---
              Host: aarch64-gnu-linux
            Target: aarch64-gnu-linux

As seen here

https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=585.347.0

there was a 5% exec time slowdown of the 505.mcf_r SPEC 2017 benchmark between
commits

r16-5291-g332d8340dff3f3
r16-5461-gb3b2da1389be9f

when run with -Ofast 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)