https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116058
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Created attachment 58744 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58744&action=edit Patch which seems to fix the issue This patch removes the parallel in the define_insn and seems to fix the issue. The problem is we don't add back the clobbers that is inside the parallel. https://gcc.gnu.org/onlinedocs/gccint/Side-Effects.html#index-parallel Does kinda of warn about this. But it is not obvious though.