https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103438
--- Comment #4 from Nils Smeds <nils.smeds at gmail dot com> --- (In reply to Andrew Pinski from comment #1) > -fprefetch-loop-arrays is not enabled by default on all targets. $ gcc --version gcc (GCC) 11.2.0 Copyright (C) 2021 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ for lvl in O0 O1 O2 O3 Os; do gcc -Q --help=optimizer -$lvl hello.c > level-$lvl-default-opt.txt 2>&1 ; done $ grep fprefetch-loop-arrays level-O*-opt.txt level-O0-default-opt.txt: -fprefetch-loop-arrays [enabled] level-O1-default-opt.txt: -fprefetch-loop-arrays [enabled] level-O2-default-opt.txt: -fprefetch-loop-arrays [enabled] level-O3-default-opt.txt: -fprefetch-loop-arrays [enabled] level-Os-default-opt.txt: -fprefetch-loop-arrays [enabled] $ grep aggressive-loop level-O*-opt.txt level-O0-default-opt.txt: -faggressive-loop-optimizations [enabled] level-O1-default-opt.txt: -faggressive-loop-optimizations [enabled] level-O2-default-opt.txt: -faggressive-loop-optimizations [enabled] level-O3-default-opt.txt: -faggressive-loop-optimizations [enabled] level-Os-default-opt.txt: -faggressive-loop-optimizations [enabled] $ grep inline-functions *txt level-O0-default-opt.txt: -finline-functions [disabled] level-O0-default-opt.txt: -finline-functions-called-once [disabled] level-O1-default-opt.txt: -finline-functions [disabled] level-O1-default-opt.txt: -finline-functions-called-once [enabled] level-O2-default-opt.txt: -finline-functions [enabled] level-O2-default-opt.txt: -finline-functions-called-once [enabled] level-O3-default-opt.txt: -finline-functions [enabled] level-O3-default-opt.txt: -finline-functions-called-once [enabled] level-Os-default-opt.txt: -finline-functions [enabled] level-Os-default-opt.txt: -finline-functions-called-once [enabled]
