From owner-freebsd-current Wed Feb 26 13:58:39 2003 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C717D37B405 for ; Wed, 26 Feb 2003 13:58:37 -0800 (PST) Received: from furao.ip.pt (furao.ip.pt [195.23.132.13]) by mx1.FreeBSD.org (Postfix) with SMTP id 3976E43F85 for ; Wed, 26 Feb 2003 13:58:36 -0800 (PST) (envelope-from qnuno@pt-quorum.com) Received: (qmail 13825 invoked from network); 26 Feb 2003 21:58:29 -0000 Received: from unknown (HELO perca.ip.pt) (195.23.132.3) by furao.ip.pt with SMTP; 26 Feb 2003 21:58:29 -0000 Received: (qmail 13773 invoked from network); 26 Feb 2003 21:58:28 -0000 Received: from unknown (HELO gw.tex.bogus) ([195.23.212.99]) (envelope-sender ) by perca.ip.pt (qmail-ldap-1.03) with SMTP for ; 26 Feb 2003 21:58:28 -0000 Received: by gw.tex.bogus (Postfix, from userid 1001) id B8DB344C2; Wed, 26 Feb 2003 21:55:48 +0000 (WET) Date: Wed, 26 Feb 2003 21:55:48 +0000 From: Nuno Teixeira To: current@FreeBSD.ORG Subject: Re: -O2 considered harmful Message-ID: <20030226215547.GA5510@gw.tex.bogus> References: <20030226113815.W5357@znfgre.tberna.bet> <20030226200635.GA1368@torment.storming.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030226200635.GA1368@torment.storming.org> X-Operating-System: FreeBSD 5.0-RELEASE-p2 User-Agent: Mutt/1.5.3i Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Hi, Just a little question: Does -march=k6-2 implies -m3dnow? Or -march=pentiumpro implies -mmmx? I always thought that when I use -march it will enable other porcessor specific optimizations like mmx and 3dnow (if available). Thanks, Nuno Teixeira On Wed, Feb 26, 2003 at 05:06:35PM -0300, Fred Souza wrote: > > I was recently a participant in a thread in another forum where all sorts > > of people, including a well respected gcc developer, said categorically > > that the latest (stock) gcc produces correct code with -O2 in all cases on > > ia32. If it doesn't, the gcc folks would like a bug report. > > I use -O3 -mmmx -m3dnow -march=k6-2 on nearly everything (things that > break with that many optimization, such as XFree86-4-libraries, I > "downgrade" to the highest optimization possible - usually -O2), and > I'm not noticing any bad impacts because of it. > > And by "nearly everything" I even meant the kernel (yes, I can respect > if anyone screams "NUTZ!@!" ;-) > > > Fred > > > -- > Insulting a person's appearance: > > That's what they mean by dark and handsome. When it's dark, you're > handsome... -- /* PGP fingerprint: C6D1 06ED EB54 A99C 6B14 6732 0A5D 810D 727D F6C6 */ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message