https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113396
--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
/* -O3 optimizations. */
{ OPT_LEVELS_3_PLUS, OPT_fgcse_after_reload, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_fipa_cp_clone, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_floop_interchange, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_floop_unroll_and_jam, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_fpeel_loops, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_fpredictive_commoning, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_fsplit_loops, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_fsplit_paths, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_ftree_loop_distribution, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_ftree_partial_pre, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_funswitch_loops, NULL, 1 },
{ OPT_LEVELS_3_PLUS, OPT_fvect_cost_model_, NULL, VECT_COST_MODEL_DYNAMIC
},
{ OPT_LEVELS_3_PLUS, OPT_fversion_loops_for_strides, NULL, 1 },
/* -O3 parameters. */
{ OPT_LEVELS_3_PLUS, OPT__param_max_inline_insns_auto_, NULL, 30 },
{ OPT_LEVELS_3_PLUS, OPT__param_early_inlining_insns_, NULL, 14 },
{ OPT_LEVELS_3_PLUS, OPT__param_inline_heuristics_hint_percent_, NULL, 600
},
{ OPT_LEVELS_3_PLUS, OPT__param_inline_min_speedup_, NULL, 15 },
{ OPT_LEVELS_3_PLUS, OPT__param_max_inline_insns_single_, NULL, 200 },
So, that is -O2 -fgcse-after-reload -fipa-cp-clone -floop-interchange
-floop-unroll-and-jam -fpeel-loops -fpredictive-commoning -fsplit-loops
-fsplit-paths -ftree-loop-distribution -ftree-partial-pre -funswitch-loops
-fvect-cost-model=dynamic -fversion-loops-for-strides
--param=max-inline-insns-auto=30 --param=early-inlining-insns=14
--param=inline-heuristics-hint-percent=600 --param=inline-min-speedup=15
--param=max-inline-insns-single=200
Of course, some further tweaks could be hidden in target files or something
could just test optimize >= 3 or similar.
