https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114414
Bug ID: 114414
Summary: [14 Regression] 15-18% exec time slowdown of 433.milc
on Zen2
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Keywords: missed-optimization, needs-bisection
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=685.70.0
there is an 18% slowdown of the 433.milc SPEC 2006 benchmark between commits
g:74e8cc28eda9b1d7
g:81ee1298b47d3f3b
The compilation options are -O2 -flto PGO. The CPU is AMD Zen2. I've replicated
this slowdown on another Zen2 machine. There the slowdown was only 15%.
Btw here is the same plot but with comparisons to GCC13 and GCC12
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=685.70.0&plot.6=921.70.0&plot.7=762.70.0
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)
