https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107409
--- Comment #9 from Rama Malladi <rvmallad at amazon dot com> --- (In reply to Martin Liška from comment #3) > Can you please share perf-profile before and after the revision? > > Note I can't see it for Altra aarch64 CPU: > https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=633.477.0&plot. > 1=683.477.0&plot.2=664.477.0&plot.3=648.477.0&plot.4=618.477.0&plot.5=605. > 477.0&plot.6=759.477.0&plot.7=584.477.0& > > However, there are huge changes in between GCC 6/7 and a newer releases. > Note the benchmark is pretty small and very sensitive to instruction caches. Hi, I got IPC data for baseline version of compiler and with this patch reverted. This is on Graviton3 processor machine, executing 1-copy rate run of 519.lbm_r. Baseline: Compiler commit ID: f896c13489d22b30d01257bc8316ab97b3359d1c Cycles: 148,489,372,938 Instructions: 382,748,379,257 IPC: 2.58 Baseline with code change in a9a4edf0e71bbac9f1b5dcecdcf9250111d16889 reverted. $ git diff gcc/tree-cfg.cc diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc index d982988048f..736432713fe 100644 --- a/gcc/tree-cfg.cc +++ b/gcc/tree-cfg.cc @@ -9984,7 +9984,7 @@ execute_fixup_cfg (void) } if (scale) { - update_max_bb_count (); +// update_max_bb_count (); compute_function_frequency (); } Cycles: 140,937,228,769 Instructions: 368,881,714,982 IPC: 2.62 >From the above, I do see the instructions executed are higher for the baseline compiler code-gen vs. the one with patch reverted. Can you please look into the code-gen and let me know if you find some perf opportunity with this patch revert? Thank you.
