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 2A66B385781E; Wed, 13 Mar 2024 19:06:28 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2A66B385781E
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1710356788;
	bh=WHUq++MgYRKYs9bXJ7khwGcFPbZ9BMt8rtFYxlbO4KY=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=v65/fXh7tFCI8i8WKkrHL+T7dQLQJhux+ToyM9Gv0Z8CzPNG9210qqKGcRziiAsdf
	 v7KSj+2Vv8dU9QGtqf66AF7/tG6BxSmUxqRvVuT6wR03swMU9LMEsrxkQCLp/XCF4I
	 0sqqVQjOXlF9CoSi4XN9/GQsTCFV+VbHVpzUTUrs=
From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114326] Missed optimization for A || B when
 !B implies A.
Date: Wed, 13 Mar 2024 19:06:27 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: tree-optimization
X-Bugzilla-Version: 14.0
X-Bugzilla-Keywords: missed-optimization
X-Bugzilla-Severity: normal
X-Bugzilla-Who: pinskia at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: everconfirmed bug_status cf_reconfirmed_on
Message-ID: <bug-114326-4-wvtXsnh5i7@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-114326-4@http.gcc.gnu.org/bugzilla/>
References: <bug-114326-4@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
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114326

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2024-03-13

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
  _1 =3D d1_5(D) ^ d2_6(D);
  _2 =3D _1 & 43981;
  _10 =3D d1_5(D) !=3D d2_6(D);
  _11 =3D _2 =3D=3D 0;
  _12 =3D _10 | _11;

(d1 !=3D d2) | ((d1 ^ d2) & CST) =3D=3D 0)

Confirmed.

Obvious if the first part is false then d1 ^ d2 will be 0.

This will work though maybe there is another place where this can be handled
...

(simplify
 (bit_ior
  (ne@n4 @0 @1)
  (cmp
   (bit_and
    (bit_xor @0 @1)
    @2)
   @3))
 (bit_ior @n4=20
  (cmp { build_zero_cst (TREE_TYPE (@0)); } @3))
)=