On Mon, 26 Oct 1998 16:13:33 EST "Foghorn Leghorn" wrote:
> >> Sony Playstation has got a MIPS. So what about GIMPS at Playstation
> ???
> >
> >The Playstation doesn't do floating point. It would be a very slow
> >platform for running GIMPS. :)
>
> Question: does Prime95 use floating point because the algorithm requires
> it, or because something about the Intel architecture makes it a good
> choice? I'm not clear about how Prime95 is able to use floating point to
> perform something that is theoretically an all-integer computation. Is
> there any platform on which an all-integer implementation would be
> superior to one that uses floating point?
In a nutshell, most platforms have much faster floating-point operations
than integer, especially in the case of FP multiply vs. integer
multiply. Also a lot of machines have larger floating point registers -
eg 64 bit FP vs. 32 bit integer.
I guess if there was an architecture that had as fast integer as
floating point, and the integer registers were the same size as the
floating point registers, then you'd probably have a platform where
integer only FFTs would be a win.
Simon.
