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From: "gabravier at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/95922] New: Failure to optimize `((b ^ a) & c) ^ a` to `(a & ~c) | (b & c)` the right way on architectures with andnot Date: Fri, 26 Jun 2020 23:17:23 +0000 [thread overview] Message-ID: <bug-95922-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95922 Bug ID: 95922 Summary: Failure to optimize `((b ^ a) & c) ^ a` to `(a & ~c) | (b & c)` the right way on architectures with andnot Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: gabravier at gmail dot com Target Milestone: --- int f(int a, int b, int c) { return ((b ^ a) & c) ^ a; } This can be optimized to `return (a & ~c) | (b & c);` on processors that have andnot instructions (at least according to LLVM, which does this transformation on x86 with -mbmi).
next reply other threads:[~2020-06-26 23:17 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-06-26 23:17 gabravier at gmail dot com [this message] 2020-06-29 9:42 ` [Bug middle-end/95922] " rguenth at gcc dot gnu.org 2020-11-20 11:06 ` jakub at gcc dot gnu.org 2020-11-20 15:04 ` gabravier at gmail dot com 2021-04-26 1:51 ` pinskia at gcc dot gnu.org 2021-12-27 5:53 ` pinskia at gcc dot gnu.org
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