From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-389540-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 21821 invoked by alias); 22 Apr 2012 10:07:11 -0000
Received: (qmail 21812 invoked by uid 22791); 22 Apr 2012 10:07:10 -0000
X-SWARE-Spam-Status: No, hits=-3.6 required=5.0	tests=ALL_TRUSTED,AWL,BAYES_00
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; Sun, 22 Apr 2012 10:06:57 +0000
From: "agner at agner dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/53071] New: Wrong instruction replacement when compiling for xop
Date: Sun, 22 Apr 2012 10:07:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c
X-Bugzilla-Keywords:
X-Bugzilla-Severity: critical
X-Bugzilla-Who: agner at agner dot org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Changed-Fields:
Message-ID: <bug-53071-4@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
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: 2012-04/txt/msg01822.txt.bz2

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53071

             Bug #: 53071
           Summary: Wrong instruction replacement when compiling for xop
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: agner@agner.org


Created attachment 27216
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27216
source code and asm output

An intrinsic vector multiply function is replaced by xop instructions when the
attached file is compiled with -mxop. Perhaps the compiler is trying to combine
a shift instruction and a multiply instruction into a single xop instruction,
but it ends up with something wrong.

This is perhaps related to bugs # 52908 and 52910.