https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69526
--- Comment #2 from rdapp at linux dot vnet.ibm.com --- Ok, that's sensible but why is the - 1 necessary in the first place? n_5 - 1 can only underflow if n_5 == 0 which is checked by testl %edx, %edx before. This is in a previous basic block, unfortunately, and will not be regarded by ivopts then (because strictly speaking, it has no influence on the induction variable)?
