From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/3632 Path: news.gmane.org!not-for-mail From: Andre Renaud Newsgroups: gmane.linux.lib.musl.general Subject: Re: Thinking about release Date: Fri, 12 Jul 2013 15:36:42 +1200 Message-ID: References: <20130709053711.GO29800@brightrain.aerifal.cx> <20130711033754.GL29800@brightrain.aerifal.cx> <20130711124613.GO29800@brightrain.aerifal.cx> <20130712031615.GS29800@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Trace: ger.gmane.org 1373600215 26422 80.91.229.3 (12 Jul 2013 03:36:55 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 12 Jul 2013 03:36:55 +0000 (UTC) To: musl@lists.openwall.com Original-X-From: musl-return-3636-gllmg-musl=m.gmane.org@lists.openwall.com Fri Jul 12 05:36:56 2013 Return-path: Envelope-to: gllmg-musl@plane.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1UxUAB-00036w-Kp for gllmg-musl@plane.gmane.org; Fri, 12 Jul 2013 05:36:55 +0200 Original-Received: (qmail 29794 invoked by uid 550); 12 Jul 2013 03:36:54 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 29786 invoked from network); 12 Jul 2013 03:36:54 -0000 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:x-gm-message-state; bh=XSBMmGLtVr9cw42H++S/cxibPLxd3K35QMXyjAIGGQI=; b=p4HlD5qCG6EshN470iQob1b3K7yEpHN1n4opQLYV+2W0N7JO+thko3WhwS9xaUyeEN kYNUDreH3zxu9Jb26rEWO0Tn2mV+aAFCJwA42QPI49/J1OsAmPjbqxHWyEwBnS7jjIX5 IDWdL127QXw/Wj6GbsIIBoADudnYgvPOEG6aL8Q2/bQegCfeHXyjovivIcUvoS4ldUtw 2j6CN1guq12k5aFkwBGHI0hgA2k8ENVn7xYInbUM9GD2Xsfyoka0xe5WopJytUwiSgUL KLoxs6E2r+T0pg7uMZ8aXd5M01LsHbT0kOF75K1ICPKUupyypPaOngfz9BxMmsPPJ1XY kWbg== X-Received: by 10.52.77.5 with SMTP id o5mr19579078vdw.46.1373600202139; Thu, 11 Jul 2013 20:36:42 -0700 (PDT) In-Reply-To: <20130712031615.GS29800@brightrain.aerifal.cx> X-Gm-Message-State: ALoCoQkrrV6mdcYCCm+HjNob3+iOxJdd7yvYLYr7Y/pFYMU/MoIyGwlm6NWlqo1qCswQQcHgNMl2 Xref: news.gmane.org gmane.linux.lib.musl.general:3632 Archived-At: > I was unable to measure any difference in performance of your version > with the prefetch hack versus simply: > > __asm__ __volatile__( > "ldmia %1!,{a4,v1,v2,v3,v4,v5,v6,v7}\n\t" > "stmia %0!,{a4,v1,v2,v3,v4,v5,v6,v7}\n\t" > : "+r"(d), "+r"(s) : > : "a4", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "memory"); What kind of machine were you using? I see a change of 115MB/s -> 105MB/s when I drop the prefetch, even using the code that you suggested. This is on an Atmel AT91sam9g45 (ARM926ejs @ 400MHz). I'm assuming this is some subtlety about how the cache is operating? Sticking the ldrhi back in brings the speed back, ie: __asm__ __volatile__( "ldmia %1!,{a4,v1,v2,v3,v4,v5,v6,v7}\n\t" "ldrhi r12, [%1]\n" "stmia %0!,{a4,v1,v2,v3,v4,v5,v6,v7}\n\t" : "+r"(d), "+r"(s) : : "a4", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "r12", "memory"); Regards, Andre