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From: "jsm28 at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/113189] `(-X * Y) * -X` can be optimized to `(X * Y) * X` Date: Mon, 01 Jan 2024 13:31:52 +0000 [thread overview] Message-ID: <bug-113189-4-NLbyacOwRn@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-113189-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113189 --- Comment #2 from Joseph S. Myers <jsm28 at gcc dot gnu.org> --- If Y is INT_MIN and X is -1, removing the negations introduces undefined behavior in the first example (-(-1) * INT_MIN * -(-1) is valid, -1 * INT_MIN * -1 has undefined behavior). For floating types, removing the negations isn't valid if flag_rounding_math.
prev parent reply other threads:[~2024-01-01 13:31 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-01-01 9:39 [Bug tree-optimization/113189] New: " pinskia at gcc dot gnu.org 2024-01-01 9:43 ` [Bug tree-optimization/113189] " pinskia at gcc dot gnu.org 2024-01-01 13:31 ` jsm28 at gcc dot gnu.org [this message]
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