https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102943
--- Comment #30 from Aldy Hernandez <aldyh at gcc dot gnu.org> --- (In reply to Jan Hubicka from comment #28) > Bit unrelated but shows that threader seems bit expensive on other builds > too. > Getting stats from cc1plus LTO-link with -flto-partition=one it seems that > backwards threader and dom are two slowest tree passes. > > We get > - 1% of build time for CCP, forward propagate, slp vectrization > - 2% of build time for cfgcleanup, VRP, PTA, PRE, FRE > - 3% of build time for dominator optimization > - 4% of build time for backwards jump threading > tree VRP : 29.83 ( 2%) 1.92 ( 3%) 32.77 ( > 2%) 354M ( 1%) ... ... > 3%) 566M ( 2%) > backwards jump threading : 49.72 ( 4%) 2.27 ( 3%) 53.04 ( This looks like the issue in PR103409. Does this fix the problem? https://gcc.gnu.org/pipermail/gcc-patches/2021-November/585658.html