https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116896
--- Comment #7 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Jakub Jelinek from comment #6) > Though, that setg %cl without xorl %ecx, %ecx first is unlikely to perform > well, the clearing would be needed. No, because subb (sbbb) opreates on bytes and no zext to full word is needed.