https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118019
--- Comment #14 from Vineet Gupta <vineetg at gcc dot gnu.org> --- (In reply to Robin Dapp from comment #7) > > The problem is GCC-15 has performance regression compare to GCC-14 on both > > strict align and we should fix it, we can't specify use no strict align in > > GCC-15 to pretend that we don't have such performance regression. > > The problem is that in GCC 15 we're now vectorizing the first loop and don't > cost it properly, most likely the vec_init/vec_construct is too inexpensive. > A solution could be two-fold: > - Increase those costs (but we can never get them really correct in case a > vec_init is just a broadcast or so) > - Enhance our vec_init expander to also allow construction from sub vectors > so the initialization becomes cheaper and we don't need to clumsily load > every uint8 element separately. The change to vectorize first loop was from Manoli's ? middle-end. I can't seem to find it - do u remember vaguely what was it about ?
