From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 26027 invoked by alias); 27 Nov 2001 07:06:36 -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 25987 invoked by uid 71); 27 Nov 2001 07:06:23 -0000 Date: Wed, 21 Nov 2001 03:43:00 -0000 Message-ID: <20011127070623.25981.qmail@sourceware.cygnus.com> To: nobody@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org, From: rth@gcc.gnu.org Subject: Re: optimization/4919: gcse inhibits loop optimization Reply-To: rth@gcc.gnu.org X-SW-Source: 2001-11/txt/msg00650.txt.bz2 List-Id: The following reply was made to PR optimization/4919; it has been noted by GNATS. From: rth@gcc.gnu.org To: gcc-bugs@gcc.gnu.org, gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, nobody@gcc.gnu.org, ottoni@ic.unicamp.br Cc: Subject: Re: optimization/4919: gcse inhibits loop optimization Date: 27 Nov 2001 07:03:49 -0000 Synopsis: gcse inhibits loop optimization State-Changed-From-To: open->suspended State-Changed-By: rth State-Changed-When: Mon Nov 26 23:03:48 2001 State-Changed-Why: GCSE did exactly what it was supposed to do -- the expression I+1, which appears twice in the body of the loop, is partially redundant with the increment of I at the end of the loop. This isn't really a problem with GCSE, but with the extreme lameness of our loop optimizer. Hopefully we'll have time to rewrite it from scratch for gcc 3.2; Jan Hubicka has already volunteered to try. http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&pr=4919&database=gcc