https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80969
--- Comment #4 from Daniel Santos <daniel.santos at pobox dot com> --- Created attachment 41794 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41794&action=edit proposed fix (still needs cleanup and tests) This still needs cleanup and tests as well as some explanations, but it appears to fix the problem and passes regression tests. I haven't tested on a machine with avx512f, however. So there is still work and testing to be done. This re-works the way the realigned stack is calculated and also reduces wasted stack space due to realignment in some cases. One drawback is that I have some code some-what duplicated in ix86_compute_frame_layout and I would like to spend some more time with it to see if I can refactor it. I will better document the changes when I have some more time.
