https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110817
--- Comment #23 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Andrew Pinski <pins...@gcc.gnu.org>: https://gcc.gnu.org/g:5e4abf4233cd34212680cca700d6438445e6a16a commit r14-4695-g5e4abf4233cd34212680cca700d6438445e6a16a Author: Andrew Pinski <apin...@marvell.com> Date: Fri Sep 1 22:09:08 2023 +0000 ssa_name_has_boolean_range vs signed-boolean:31 types This turns out to be a latent bug in ssa_name_has_boolean_range where it would return true for all boolean types but all of the uses of ssa_name_has_boolean_range was expecting 0/1 as the range rather than [-1,0]. So when I fixed vector lower to do all comparisons in boolean_type rather than still in the signed-boolean:31 type (to fix a different issue), the pattern in match for `-(type)!A -> (type)A - 1.` would assume A (which was signed-boolean:31) had a range of [0,1] which broke down and sometimes gave us -1/-2 as values rather than what we were expecting of -1/0. This was the simpliest patch I found while testing. We have another way of matching [0,1] range which we could use instead of ssa_name_has_boolean_range except that uses only the global ranges rather than the local range (during VRP). I tried to clean this up slightly by using gimple_match_zero_one_valuedp inside ssa_name_has_boolean_range but that failed because due to using only the global ranges. I then tried to change get_nonzero_bits to use the local ranges at the optimization time but that failed also because we would remove branches to __builtin_unreachable during evrp and lose information as we don't set the global ranges during evrp. OK? Bootstrapped and tested on x86_64-linux-gnu. PR tree-optimization/110817 gcc/ChangeLog: * tree-ssanames.cc (ssa_name_has_boolean_range): Remove the check for boolean type as they don't have "[0,1]" range. gcc/testsuite/ChangeLog: * gcc.c-torture/execute/pr110817-1.c: New test. * gcc.c-torture/execute/pr110817-2.c: New test. * gcc.c-torture/execute/pr110817-3.c: New test.
