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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/107880] New: bool tautology missed optimisation Date: Sat, 26 Nov 2022 18:03:24 +0000 [thread overview] Message-ID: <bug-107880-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107880 Bug ID: 107880 Summary: bool tautology missed optimisation Product: gcc Version: 13.0 Status: UNCONFIRMED Keywords: missed-optimization Severity: enhancement Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: pinskia at gcc dot gnu.org Target Milestone: --- From bug 91882 comment #1 (since the testcase in that was in bug 91882 comment #0 is now fixed): bool impl(bool a, bool b) { return (!a || b); } // bad optimisation bool always_true(bool a, bool b) { return (impl(a,b) == impl(b,a)) == (a == b); // ( (a -> b) = (b -> a) ) = (a = b) tautology }
next reply other threads:[~2022-11-26 18:03 UTC|newest] Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-11-26 18:03 pinskia at gcc dot gnu.org [this message] 2022-11-26 18:06 ` [Bug tree-optimization/107880] " pinskia at gcc dot gnu.org 2022-11-26 18:11 ` pinskia at gcc dot gnu.org 2023-05-24 1:15 ` pinskia at gcc dot gnu.org 2023-08-28 20:36 ` pinskia at gcc dot gnu.org 2023-08-28 21:30 ` pinskia at gcc dot gnu.org 2023-08-28 22:52 ` pinskia at gcc dot gnu.org 2023-09-12 15:03 ` pinskia at gcc dot gnu.org
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