https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86497
--- Comment #3 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Jakub Jelinek from comment #2) > Started with r254167, so maybe related to PR84251. Yes, it is the same issue. As said in PR84251, we have to wrap COMPARE into UNSPEC, so this defeats some passes (in this case fwprop1 pass) that look at RTX code of the pattern.