https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88361
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- is executed at most 19 (bounded by 19) + 1 times in loop 1. Analyzing # of iterations of loop 1 exit condition [19, + , 4294967295] != 0 bounds on difference of bases: -19 ... -19 result: # of iterations 19, bounded by 19 Loop 1 iterates 19 times. Loop 1 iterates at most 19 times. Loop 1 likely iterates at most 19 times. Not unrolling loop 1 (--param max-completely-peel-times limit reached). Increasing the param allows the loop to be unrolled.