https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103514
--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:263a5944fc806396ecc3eff3d96277602e88ae2b commit r12-6942-g263a5944fc806396ecc3eff3d96277602e88ae2b Author: Jakub Jelinek <ja...@redhat.com> Date: Mon Jan 31 10:30:58 2022 +0100 testsuite: Fix up tree-ssa/pr103514.c testcase [PR103514] > > PR tree-optimization/103514 > > * match.pd (a & b) ^ (a == b) -> !(a | b): New optimization. > > * match.pd (a & b) == (a ^ b) -> !(a | b): New optimization. > > * gcc.dg/tree-ssa/pr103514.c: Testcase for this optimization. > > > > 1) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103514 > Note the bug was filed an fixed during stage3, review just didn't happen in > a reasonable timeframe. > > I'm going to ACK this for the trunk and go ahead and commit it for you. The testcase FAILs on short-circuit targets like powerpc64le-linux. While the first 2 functions are identical, the last two look like: <bb 2> : if (a_5(D) != 0) goto <bb 3>; [INV] else goto <bb 4>; [INV] <bb 3> : if (b_6(D) != 0) goto <bb 5>; [INV] else goto <bb 4>; [INV] <bb 4> : <bb 5> : # iftmp.1_4 = PHI <1(3), 0(4)> _1 = a_5(D) == b_6(D); _2 = (int) _1; _3 = _2 ^ iftmp.1_4; _9 = _2 != iftmp.1_4; return _9; instead of the expected: <bb 2> : _3 = a_8(D) & b_9(D); _4 = (int) _3; _5 = a_8(D) == b_9(D); _6 = (int) _5; _1 = a_8(D) | b_9(D); _2 = ~_1; _7 = (int) _2; _10 = ~_1; return _10; so no wonder it doesn't match. E.g. x86_64-linux will also use jumps if it isn't just a && b but a && b && c && d (will do a & b and c & d tests and jump based on those. As it is too late to implement this optimization even for the short circuiting targets this late (not even sure which pass would be best), this patch just forces non-short-circuiting for the test. 2022-01-31 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/103514 * gcc.dg/tree-ssa/pr103514.c: Add --param logical-op-non-short-circuit=1 to dg-options.
