https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107833
--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So, do we whack-a-mole in this case some more and try harder in
mark_ssa_maybe_undefs
by basically repeating the CCP4 UNDEFINED propagation, or invent some new stmt
or marking that IVOPTS could use before the loop to turn possibly undefined
into undefined but always the same random pattern within the same invocation
(kind of like asm ("" : "+g" (undef));), or something else (like after IVOPTS
stop the UNDEFINED propagation on loop header PHIs or something similar)?
