https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79514
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Created attachment 40868 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40868&action=edit gcc7-pr79514.patch You mean like this? That certainly works for x86, but I'm afraid it is going to break or penalize various other arches. The thing is, HAVE_PRE_MODIFY_DISP is set to 1 only on 5 targets, but quick grep reveals that there are many more targets that somehow handle pre_modify or have insn patterns using that. This is not unlike HAVE_PRE_DEC and similar, x86 also doesn't claim it has HAVE_PRE_DEC, yet it uses it for pushes. So I think pushxf1 expander in i386.md is the way to go.
