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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/52409] New: ((~a)|(~b)) is not simplified at the tree level Date: Tue, 28 Feb 2012 07:13:00 -0000 [thread overview] Message-ID: <bug-52409-4@http.gcc.gnu.org/bugzilla/> (raw) http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52409 Bug #: 52409 Summary: ((~a)|(~b)) is not simplified at the tree level Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: enhancement Priority: P3 Component: tree-optimization AssignedTo: unassigned@gcc.gnu.org ReportedBy: pinskia@gcc.gnu.org Take: int f(int a, int b) { a = ~a; b = ~b; return a|b; } int g(int a, int b) { return ~(a&b); } --- CUT --- Currently the tree level does not try to combine them, fold does it though. I saw this with bools in GCC itself. In the bool case, we can fold it further to just (a&b) == 0. Likewise for (~a)&(~b) into ~(a|b).
next reply other threads:[~2012-02-28 7:12 UTC|newest] Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-02-28 7:13 pinskia at gcc dot gnu.org [this message] 2012-02-28 7:16 ` [Bug tree-optimization/52409] " pinskia at gcc dot gnu.org
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