https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121143
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Before cunroll that first loop is
<bb 18> [local count: 8680598903]:
# __n_274 = PHI <__n_206(43), 0(39)>
# ivtmp_255 = PHI <ivtmp_374(43), 9(39)>
__n_206 = __n_274 + 1;
ivtmp_374 = ivtmp_255 - 1;
if (ivtmp_374 != 0)
goto <bb 43>; [89.00%]
else
goto <bb 21>; [11.00%]
<bb 43> [local count: 7725733029]:
goto <bb 18>; [100.00%]
