From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12233 invoked by alias); 18 Mar 2004 16:18:31 -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 12218 invoked from network); 18 Mar 2004 16:18:30 -0000 Received: from unknown (HELO av.mvista.com) (12.44.186.158) by sources.redhat.com with SMTP; 18 Mar 2004 16:18:30 -0000 Received: from mvista.com (av [127.0.0.1]) by av.mvista.com (8.9.3/8.9.3) with ESMTP id IAA04282; Thu, 18 Mar 2004 08:18:20 -0800 Message-ID: <4059CBA5.FD8D4C73@mvista.com> Date: Thu, 18 Mar 2004 16:18:00 -0000 From: Michael Eager Organization: MontaVista Software, Inc. MIME-Version: 1.0 To: Richard Sandiford CC: Phil Edwards , gcc , libstdc++@gcc.gnu.org, Paul Koning Subject: Re: locking problem with mips atomicity References: <20040316045706.GA5985@redhat.com> <405726C9.86724574@mvista.com> <1079458507.3799.8.camel@dzur.sfbay.redhat.com> <40573D8F.DAAB6354@mvista.com> <20040316183443.GB12315@redhat.com> <4057833F.37693319@mvista.com> <20040316232242.GA6879@redhat.com> <40579942.3B51A8B3@mvista.com> <20040317004432.GA24875@disaster.jaj.com> <4057A10E.1968551E@mvista.com> <20040317005526.GA25735@disaster.jaj.com> <4058D42A.EA714F43@mvista.com> <877jxito0c.fsf@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-SW-Source: 2004-03/txt/msg01055.txt.bz2 Richard Sandiford wrote: > > Michael Eager writes: > > I've revised the patch. It now only has constraints which are referenced. > > I added a "memory" constraint. > > Sorry if I've missed the explanation, but why is using a memory clobber > an improvement over an unused memory operand? The location which is clobbered is unknown. From what I understand, an unused memory operand is ignored. -- Michael Eager eager@mvista.com 408-328-8426 MontaVista Software, Inc. 1237 E. Arques Ave., Sunnyvale, CA 94085