> I think it's incorrect to say so in general. For example, on x86/64: > > $ make mrproper > $ make allyesconfig > $ make && mv vmlinux vmlinux-000 > $ make coccicheck MODE=patch COCCI=scripts/coccinelle/misc/unlikely.cocci | > patch -p1 > $ make > $ ./scripts/bloat-o-meter ./vmlinux-000 ./vmlinux > add/remove: 0/0 grow/shrink: 3/4 up/down: 41/-35 (6) > Function old new delta > dpaa2_io_service_rearm 357 382 +25 > intel_pmu_hw_config 1277 1285 +8 > get_sigframe.isra.constprop 1657 1665 +8 > csum_partial_copy_from_user 605 603 -2 > wait_consider_task 3807 3797 -10 > __acct_update_integrals 384 373 -11 > pipe_to_sendpage 459 447 -12 > Total: Before=312759461, After=312759467, chg +0.00% > > It definitely influence the way the compiler optimizes the code.
Small addition: Results with allyesconfig and KCOV, KASAN, KUBSAN, FTRACE, TRACE_BRANCH_PROFILING, PROFILE_ALL_BRANCHES disabled: ./scripts/bloat-o-meter ./vmlinux-000 ./vmlinux add/remove: 0/0 grow/shrink: 2/3 up/down: 22/-22 (0) Function old new delta i40e_xmit_xdp_ring 457 477 +20 __acct_update_integrals 127 129 +2 csum_partial_copy_from_user 208 207 -1 dpaa2_io_service_rearm 180 177 -3 wait_consider_task 1338 1320 -18 For defconfig: ./scripts/bloat-o-meter ./vmlinux-000 ./vmlinux add/remove: 0/0 grow/shrink: 3/1 up/down: 16/-5 (11) Function old new delta do_signal 1513 1521 +8 wait_consider_task 2151 2157 +6 __acct_update_integrals 127 129 +2 csum_partial_copy_from_user 223 218 -5 Denis
