Re: [RFC] div64_64 support II
The problem with these algorithms that tradoff one or more multiplies in order to avoid a divide is that they don't give anything and often lose when both multiplies and divides are emulated in software. Actually on rereading this: is there really any Linux port that emulates multiplies in software? I thought that was only done on really small microcontrollers or smart cards; but anything 32bit+ that runs Linux should have hardware multiply, shouldn't it? -Andi - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC] div64_64 support II
Andi Kleen [EMAIL PROTECTED] writes: Actually on rereading this: is there really any Linux port that emulates multiplies in software? I thought that was only done on really small microcontrollers or smart cards; but anything 32bit+ that runs Linux should have hardware multiply, shouldn't it? SPARCv7 (sun4/sun4c) doesn't have hardware mul/div. This includes SparcStation 1, 1+, 2, SLC, ELC, IPC and IPX. -- ilmari A disappointingly low fraction of the human race is, at any given time, on fire. - Stig Sandbeck Mathisen - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC] div64_64 support II
From: [EMAIL PROTECTED] (Dagfinn Ilmari Mannsåker) Date: Tue, 06 Mar 2007 18:43:14 +0100 Andi Kleen [EMAIL PROTECTED] writes: Actually on rereading this: is there really any Linux port that emulates multiplies in software? I thought that was only done on really small microcontrollers or smart cards; but anything 32bit+ that runs Linux should have hardware multiply, shouldn't it? SPARCv7 (sun4/sun4c) doesn't have hardware mul/div. This includes SparcStation 1, 1+, 2, SLC, ELC, IPC and IPX. Right and the cypress sun4m parts don't do multiply/divide in hardware either. I believe the Alpha does divide in software too, see arch/alpha/lib/divide.S - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC] div64_64 support II
Andi Kleen wrote: The problem with these algorithms that tradoff one or more multiplies in order to avoid a divide is that they don't give anything and often lose when both multiplies and divides are emulated in software. Actually on rereading this: is there really any Linux port that emulates multiplies in software? I thought that was only done on really small microcontrollers or smart cards; but anything 32bit+ that runs Linux should have hardware multiply, shouldn't it? SPARC v8 does multiplies using an MSTEP instruction. -hpa - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
