https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115069
--- Comment #17 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Haochen Jiang from comment #15) > I am doing like this way. Suppose should be same as Comment 8. Yes, but IMO the patch in Comment #8 better describes where the problem is. Please note that without VPMOVWB we fall-back to the original ix86_expand_vecop_qihi, where the expansion is implemented in a different way. (BTW: If there is a better way to emulate VPMOVWB, it should be implemented in vec-perm routines, it will universally benefit this permutation. In this case, early exit, as introduced in the mentioned patch, could be removed.)
