On 14 May 2001, at 9:08, George Woltman wrote:
> At 01:02 AM 5/14/2001 -0700, xqrpa wrote:
> >Is ordinary factoring code also present ("Factor Only") and is
> >there a corresponding speed-up?
>
> The factoring code is present but unchanged. Thus, no speedup.
... except for the fact that the slowest P4 processor runs about as
fast as the fastest Athlon, and is also supposed to be more efficient
at executing integer instructions.
Trial factoring seems to be well in advance of LL testing, so it
probably doesn't matter too much. But is there any scope for using
SSE2, or even MMX / 3DNow, extensions in trial factoring? The point
being that trial factoring can be implemented reasonably efficiently
as almost pure integer code.
If we could test two or four factors in parallel, we should get a
considerable speedup, even though some of the "threads" would spend
some time "stalled" whilst exceptions were dealt with in another.
Regards
Brian Beesley
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