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 A3EC5383540C; Fri, 15 Jan 2021 01:35:29 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A3EC5383540C
From: "rjiejie at me dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/98673] pass fre4 inhibit pass dom3 to create
 much more optimized code
Date: Fri, 15 Jan 2021 01:35:29 +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: 10.2.0
X-Bugzilla-Keywords: missed-optimization
X-Bugzilla-Severity: normal
X-Bugzilla-Who: rjiejie at me dot com
X-Bugzilla-Status: UNCONFIRMED
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: 
Message-ID: <bug-98673-4-mF2ZAPcMFg@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-98673-4@http.gcc.gnu.org/bugzilla/>
References: <bug-98673-4@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: Fri, 15 Jan 2021 01:35:29 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98673

--- Comment #2 from jojo <rjiejie at me dot com> ---
(In reply to Richard Biener from comment #1)
> The analysis sounds a bit confused.  What is the transform that DOM cannot
> do after the transform that FRE does?  There's some older bug about
> out-of-SSA
> coalescing issues with loops and liveness of induction variables but it's
> not clear if this is related (the assembly doesn't show the loop exit blo=
ck).
>=20
> Can you name the loop in the source that is problematic?
>=20

see this loop:

      for( i1 =3D 0 ; i1 < ( numXEntries - 1 ) ; i1++ )
        {
            if( ( loadValue < engLoad[i1+1] ) && ( loadValue >=3D engLoad[i=
1] ) )
            {
                break ;
            }
        }=