Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965006AbVI0Qsn (ORCPT ); Tue, 27 Sep 2005 12:48:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965007AbVI0Qsn (ORCPT ); Tue, 27 Sep 2005 12:48:43 -0400 Received: from scrub.xs4all.nl ([194.109.195.176]:26846 "EHLO scrub.xs4all.nl") by vger.kernel.org with ESMTP id S965006AbVI0Qsm (ORCPT ); Tue, 27 Sep 2005 12:48:42 -0400 Date: Tue, 27 Sep 2005 18:48:01 +0200 (CEST) From: Roman Zippel X-X-Sender: roman@scrub.home To: Thomas Gleixner cc: Ingo Molnar , Christopher Friesen , linux-kernel@vger.kernel.org, akpm@osdl.org, george@mvista.com, johnstul@us.ibm.com, paulmck@us.ibm.com Subject: Re: [ANNOUNCE] ktimers subsystem In-Reply-To: <1127682122.15115.97.camel@tglx.tec.linutronix.de> Message-ID: References: <20050919184834.1.patchmail@tglx.tec.linutronix.de> <1127342485.24044.600.camel@tglx.tec.linutronix.de> <43333EBA.5030506@nortel.com> <1127458197.24044.726.camel@tglx.tec.linutronix.de> <20050924051643.GB29052@elte.hu> <1127570212.15115.77.camel@tglx.tec.linutronix.de> <1127682122.15115.97.camel@tglx.tec.linutronix.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1064 Lines: 27 Hi, On Sun, 25 Sep 2005, Thomas Gleixner wrote: > On Sun, 2005-09-25 at 01:45 +0200, Roman Zippel wrote: > > > The multiply is not necessarly cheap, if the arch has no 32x32->64 > > instruction, gcc will generate a call to __muldi3(). > > Can you please point out which architectures do not have a 32x32->64 > instruction ? I have no complete overview. I know that Motorola actually removed that instruction in the M68060 (it causes an emulation trap) and it's still not back in newer ColdFire cpus. For arm it's an optional instruction in earlier versions (v3). For ppc it's splitted into two instructions. For the rest you might want to check , if div64 has to be emulated, there are good chances this instruction has to be emulated as well (especially in smaller embedded archs). bye, Roman - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/