https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83304
--- Comment #4 from Segher Boessenkool <segher at gcc dot gnu.org> --- With r255384 combine manages to do many more combinations. Without it, it can get rid of most of the loop body (which should have been optimised away in gimple already really). I don't see how it would abort, but I find that "it" stuff really hard to read, so I might be missing something.
