General mpn_gcd_basecase

Marco Bodrato bodrato at
Sun Sep 1 01:26:42 UTC 2019


Il Dom, 1 Settembre 2019 1:30 am, Torbjörn Granlund ha scritto:
> "Marco Bodrato" <bodrato at> writes:
>   I think that the scaling trick is interesting, and should be always
>   used. Does this mean that we should only use submul? Well...
>   let's use submul only :-)
> We'll need negation, I suppose.  Or a rsbmul_1 which we choose wisely.

In an unlikely branch.

>   Please try the attached code. It's based on yours.

> I will look at it and test it after some sleep!

Before you wake up, I send you another version. I added two more bits to
the table entries, and started using one with some bit trickery
(exploiting symmetries). It should be able to gain a bit of "speed", but
in the unlikely  case of operands of very different sizes only.


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