Messages in this thread | | | Date | Tue, 6 Mar 2007 12:04:33 -0800 | From | Stephen Hemminger <> | Subject | Re: [RFC] div64_64 support |
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On Tue, 6 Mar 2007 20:48:41 +0100 Andi Kleen <andi@firstfloor.org> wrote:
> On Tue, Mar 06, 2007 at 10:29:41AM -0800, Stephen Hemminger wrote: > > Don't count the existing Newton-Raphson out. It turns out that to get enough > > precision for 32 bits, only 4 iterations are needed. By unrolling those, it > > gets much better timing. > > But did you fix the >2^43 bug too?
It was caused by not doing x^2 in 64 bit.
> > SGI has already shipped 10TB Altixen, so it's not entirely theoretical. > > -Andi >
-- Stephen Hemminger <shemminger@linux-foundation.org> - 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/
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