https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118996
--- Comment #8 from H.J. Lu <hjl.tools at gmail dot com> --- Created attachment 60607 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=60607&action=edit A patch Here is the patch to change TARGET_SMALL_REGISTER_CLASSES_FOR_MODE_P to return false for x86-64.