https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61094
--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Sure, there, or merge_def_and_ext, or combine_reaching_defs. In any case, what I'm afraid of is that when there are two extensions, you in the first round verify that a copy is suitable and so is the new extension insn, but then you widen the extension insn even further, the widening succeeds, but nothing verifies the copy insn that is now to be performed in the even wider mode compared from what has been verified earlier. And in the wider mode it might be unsupported.
