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)