From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 14138 invoked by alias); 27 May 2005 15:09:45 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 14097 invoked by uid 22791); 27 May 2005 15:09:40 -0000 Received: from yosemite.airs.com (HELO yosemite.airs.com) (205.217.158.180) by sourceware.org (qpsmtpd/0.30-dev) with SMTP; Fri, 27 May 2005 15:09:40 +0000 Received: (qmail 18407 invoked by uid 10); 27 May 2005 15:09:10 -0000 Received: (qmail 21461 invoked by uid 500); 27 May 2005 15:09:01 -0000 To: Sanjiv Kumar Gupta Cc: gcc@gcc.gnu.org Subject: Re: GCC 3.3.1 -O2 problem with sqrt.c References: <20050527120338.26135.qmail@web50104.mail.yahoo.com> From: Ian Lance Taylor Date: Fri, 27 May 2005 17:49:00 -0000 In-Reply-To: <20050527120338.26135.qmail@web50104.mail.yahoo.com> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2005-05/txt/msg01501.txt.bz2 Sanjiv Kumar Gupta writes: > I am using gcc 3.3.1 release as my port, and looks > like I have hit a problem with greg. You neglected to mention what target you are using. > I couldn't understand why the insns 620 and 621 are > being generated here as DI moves. I'm not sure specifically why it got a DI move here, but it doesn't look wrong. It's treating the struct named parts as DImode. > This is creating problem since insn 621 gets splitted > after reload into two SI moves,i.e. @(r21, -8) and > @(r21, -4). > This renders insns 619 as dead and hence insns 618 and > insn 429 as dead, which are eliminated by flow2. It does look rather suspicious, but it's hard to know whether it is wrong without seeing the value in r1. Does the behaviour change if you use -fno-strict-aliasing? (I can't remember what the default was in 3.3.1). Ian