https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91450
--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Author: jakub Date: Thu Nov 21 17:18:17 2019 New Revision: 278583 URL: https://gcc.gnu.org/viewcvs?rev=278583&root=gcc&view=rev Log: Backported from mainline 2019-11-19 Jakub Jelinek <ja...@redhat.com> PR middle-end/91450 * internal-fn.c (expand_mul_overflow): For s1 * s2 -> ur, if one operand is negative and one non-negative, compare the non-negative one against 0 rather than comparing s1 & s2 against 0. Otherwise, don't compare (s1 & s2) == 0, but compare separately both s1 == 0 and s2 == 0, unless one of them is known to be negative. Remove tem2 variable, use tem where tem2 has been used before. * gcc.c-torture/execute/pr91450-1.c: New test. * gcc.c-torture/execute/pr91450-2.c: New test. Added: branches/gcc-8-branch/gcc/testsuite/gcc.c-torture/execute/pr91450-1.c branches/gcc-8-branch/gcc/testsuite/gcc.c-torture/execute/pr91450-2.c Modified: branches/gcc-8-branch/gcc/ChangeLog branches/gcc-8-branch/gcc/internal-fn.c branches/gcc-8-branch/gcc/testsuite/ChangeLog