From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id 0EA7C385840E; Wed, 24 Nov 2021 13:04:34 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 0EA7C385840E
From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/103406] [12 Regression] gcc -O0 behaves differently
 on "DBL_MAX related operations" than gcc -O1 and above
Date: Wed, 24 Nov 2021 13:04:34 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: middle-end
X-Bugzilla-Version: 11.1.0
X-Bugzilla-Keywords: wrong-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: rguenth at gcc dot gnu.org
X-Bugzilla-Status: ASSIGNED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: roger at nextmovesoftware dot com
X-Bugzilla-Target-Milestone: 12.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-103406-4-1ZkpnbKY4x@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-103406-4@http.gcc.gnu.org/bugzilla/>
References: <bug-103406-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Wed, 24 Nov 2021 13:04:35 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103406

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
simplify_binary_operation_1 has

      /* ((-a) + b) -> (b - a) and similarly for (a + (-b)).  These
         transformations are safe even for IEEE.  */
      if (GET_CODE (op0) =3D=3D NEG)
        return simplify_gen_binary (MINUS, mode, op1, XEXP (op0, 0));
      else if (GET_CODE (op1) =3D=3D NEG)
        return simplify_gen_binary (MINUS, mode, op0, XEXP (op1, 0));=