https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64309
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> --- (1 << n) & 5 != 0 -> n == 0 || n == 2 (not beneficial) Not only that, we actually emit similar comparisons as a bit test intentionally even if you write it in a switch or series of ifs that way, so undoing that optimization would be a bad idea.
