From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-return-92933-listarch-gcc=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 2724 invoked by alias); 18 Mar 2004 00:13:17 -0000
Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Archive: <http://gcc.gnu.org/ml/gcc/>
List-Post: <mailto:gcc@gcc.gnu.org>
List-Help: <http://gcc.gnu.org/ml/>
Sender: gcc-owner@gcc.gnu.org
Received: (qmail 2712 invoked from network); 18 Mar 2004 00:13:16 -0000
Received: from unknown (HELO frothingslosh.sfbay.redhat.com) (66.187.237.200)
  by sources.redhat.com with SMTP; 18 Mar 2004 00:13:16 -0000
Received: from frothingslosh.sfbay.redhat.com (localhost.localdomain [127.0.0.1])
	by frothingslosh.sfbay.redhat.com (8.12.10/8.12.10) with ESMTP id i2I0DEIS011352;
	Wed, 17 Mar 2004 16:13:14 -0800
Received: (from rth@localhost)
	by frothingslosh.sfbay.redhat.com (8.12.10/8.12.10/Submit) id i2I0DESQ011350;
	Wed, 17 Mar 2004 16:13:14 -0800
X-Authentication-Warning: frothingslosh.sfbay.redhat.com: rth set sender to rth@redhat.com using -f
Date: Thu, 18 Mar 2004 01:02:00 -0000
From: Richard Henderson <rth@redhat.com>
To: Michael Eager <eager@mvista.com>
Cc: Phil Edwards <phil@jaj.com>, gcc <gcc@gcc.gnu.org>, libstdc++@gcc.gnu.org,
        Paul Koning <pkoning@equallogic.com>
Subject: Re: locking problem with mips atomicity
Message-ID: <20040318001314.GA11256@redhat.com>
Mail-Followup-To: Richard Henderson <rth@redhat.com>,
	Michael Eager <eager@mvista.com>, Phil Edwards <phil@jaj.com>,
	gcc <gcc@gcc.gnu.org>, libstdc++@gcc.gnu.org,
	Paul Koning <pkoning@equallogic.com>
References: <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> <4058D4F4.6364BC6E@mvista.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <4058D4F4.6364BC6E@mvista.com>
User-Agent: Mutt/1.4.1i
X-SW-Source: 2004-03/txt/msg01014.txt.bz2

On Wed, Mar 17, 2004 at 02:45:08PM -0800, Michael Eager wrote:
> +       "ll	%0,0(%2)\n\t"
> +       "addu	%1,%3,%0\n\t"
> +       "sc	%1,0(%2)\n\t"
>         ".set	pop\n\t"
>         "beqz	%1,1b\n\t"
>         "/* End exchange & add */"
> +       : "=&r"(__result), "=&r"(__tmp), "+r"(__mem)

Why the in-out constraint on __mem?  You don't modify %2.


r~