https://gcc.gnu.org/bugzilla/show_bug.cgi?id=35341
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Currently we get at -O2: Estimating sizes for loop 1 BB: 3, after_exit: 0 size: 1 _1 = i_13 * 2; Induction variable computation will be folded away. size: 1 _2 = a[_1]; size: 1 _3 = a[i_13]; size: 1 _4 = _2 + _3; size: 1 a[_1] = _4; size: 2 if (_4 == 10) BB: 6, after_exit: 1 BB: 4, after_exit: 0 size: 1 i_10 = i_13 + 1; Induction variable computation will be folded away. size: 1 ivtmp_7 = ivtmp_12 - 1; Induction variable computation will be folded away. size: 2 if (ivtmp_7 != 0) Exit condition will be eliminated in peeled copies. Exit condition will be eliminated in last copy. Constant conditional. size: 11-5, last_iteration: 11-5 Loop size: 11 Estimated size after unrolling: 20 Not unrolling loop 1: size would grow. We do unroll at -O3.
