Exact division

Paul Zimmermann Paul.Zimmermann at loria.fr
Thu Dec 10 15:07:48 CET 2009


>   With bdiv_q now working, I wrote a simple divexact function, and I use
>   it in mpn/gcdext.c where it needs to compute the second cofactor. As a
>   result, the GCDEXT_DC_THRESHOLD on shell was reduced from 496 to around
>   415. I guess it would be reduced a little more more with a more clever
>   bidirectional divexact.
> I added summary date at the threshold tables, see
> <http://gmplib.org/devel/GCDEXT_DC_THRESHOLD.html>.
> "cfg/meas avg: 0.80180" means that the average configured threshold
> divided by the average measured threshold is 0.80180.  A significant
> move of a threshold!

do you mean meas/cfg instead (I guess "measured" is the threshold measured
by the tuning program, while "configured" is the one in gmp-mparams.h, i.e.,
the threshold from the previous day)?

I notice on the contrary SET_STR_DC_THRESHOLD got multiplied by 1.22 on

What would be nice would be to have those meas/cfg values also in the main
table on http://gmplib.org/devel/thresholds.html, with green colors to
indicate ratios < 0.90, and red colors for ratios > 1.10...


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