From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9415 invoked by alias); 28 Jan 2003 22:16:01 -0000 Mailing-List: contact gcc-prs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-prs-owner@gcc.gnu.org Received: (qmail 9391 invoked by uid 71); 28 Jan 2003 22:16:01 -0000 Date: Tue, 28 Jan 2003 22:16:00 -0000 Message-ID: <20030128221601.9390.qmail@sources.redhat.com> To: ebotcazou@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org, From: Gabriel Dos_Reis Subject: Re: optimization/9279: [3.2 regression] [Sparc] combine bug Reply-To: Gabriel Dos_Reis X-SW-Source: 2003-01/txt/msg01639.txt.bz2 List-Id: The following reply was made to PR optimization/9279; it has been noted by GNATS. From: Gabriel Dos_Reis To: Matthias Klose Cc: Eric Botcazou , ebotcazou@gcc.gnu.org, frank@g-n-u.de, gcc-bugs@gcc.gnu.org, gcc-gnats@gcc.gnu.org Subject: Re: optimization/9279: [3.2 regression] [Sparc] combine bug Date: Tue, 28 Jan 2003 23:07:11 +0100 (MET) | Eric Botcazou writes: | > > The fix introduces a performance regression for PowerPC (and possibly | > > other platforms) on the 3.2 branch. | > | > Now reverted for this reason on the 3.2 branch so GCC 3.2.2 will ship with | > the bug. | | I see you having the choice between two regressions, one performance | regression (from 3.2.1 to 3.2.2) and one "wrong code" regression (from | 2.95 and 3.0.4 to 3.2.2). Not sure, if I should like your decision. As I explained to Eric, I would have been pleased to apply that patch. However it turned out that it introduces (1) a performance regression; (2) possibly a wrong code generation -- David gave some references. Therefore, to fix the new regressions we would have to grab other patches not known to be safe. The initial patch was beginning to have too much ramifications. That is why I asked Eric to revert his patch. I would suggest that, right after 3.2.2 release, interested parties investigate the issue and submit a complete patch which we would have sufficient time to test. -- Gaby