https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96789
--- Comment #28 from Hongtao.liu <crazylht at gmail dot com> --- > Probably you can try to tweak it in ix86_add_stmt_cost? when the statement Yes, it's the place. > is UB to UH conversion statement, further check if the def of the input UB > is MEM. Only if there's no multi-use for UB. More generally, it's quite difficult to guess later optimizations for the purpose of more accurate vectorization cost model, :(.
