From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-349105-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 29354 invoked by alias); 4 Mar 2011 16:06:58 -0000
Received: (qmail 29341 invoked by uid 22791); 4 Mar 2011 16:06:56 -0000
X-SWARE-Spam-Status: No, hits=-2.8 required=5.0	tests=ALL_TRUSTED,AWL,BAYES_00,TW_TM
X-Spam-Check-By: sourceware.org
Received: from localhost (HELO gcc.gnu.org) (127.0.0.1)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 04 Mar 2011 16:06:52 +0000
From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/47989] -mrecip causes 482.sphinx3 and 464.h264ref to miscompare
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: target
X-Bugzilla-Keywords:
X-Bugzilla-Severity: enhancement
X-Bugzilla-Who: rguenth at gcc dot gnu.org
X-Bugzilla-Status: ASSIGNED
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: rguenth at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Changed-Fields: Status Last reconfirmed AssignedTo Summary Ever Confirmed
Message-ID: <bug-47989-4-AeOUlAHXXJ@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-47989-4@http.gcc.gnu.org/bugzilla/>
References: <bug-47989-4@http.gcc.gnu.org/bugzilla/>
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
Content-Type: text/plain; charset="UTF-8"
MIME-Version: 1.0
Date: Fri, 04 Mar 2011 16:06:00 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
X-SW-Source: 2011-03/txt/msg00418.txt.bz2

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47989

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2011.03.04 16:06:42
         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org
                   |gnu.org                     |
            Summary|-mrecip causes 482.sphinx3  |-mrecip causes 482.sphinx3
                   |to miscompare               |and 464.h264ref to
                   |                            |miscompare
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-04 16:06:42 UTC ---
Similarly 464.h264ref miscompares because of

  fprintf(stdout, "Freq. for encoded bitstream: %1.0f\n",
          img->framerate/(float)(input->jumpd+1));

where both img->framerate and input->jumpd are input parameters
(15.0 and 1).  Here the rounding to integer happens inside fprintf.

Feeding rcps sequences into call stmts is probably never a very good idea.



Mine.  I'm going to move rcps expansion up into tree-ssa-math-opts, the
same place where we apply LCM for CSE-ing 1/x.  Probably replace the
division by a builtin.