udiv_qr_3by2 vs divappr

[paul zimmermann]

       Niels,

> static inline mp_limb_t
> divappr_2 (mp_limb_t n2, mp_limb_t n1,
>            mp_limb_t d1, mp_limb_t d0, mp_limb_t dinv)
> This needs more analysis. [...]

you might be interested by Algorithms DivApprox1 and DivApprox2
from https://hal.inria.fr/hal-01502326.

Best regards,
Paul