squaring modulo an integer

[Torbjorn Granlund]

"Jürgen Bullinger" <juergen.bullinger at gmx.net> writes:

  I have another question.
  Are there special routines in gmp to do squaring modulo an integer?

No.

  If not, what do you think, are there any performance improvements possible
  squaring numbers with a special purpose function (in comparison to mpz_powm
  or a multiplication algorithm modulo an integer ?mpz_mulm?)?

At the low level, special squaring code will be used for mpz(r,a,a).
See mpn_mul and mpn_mul_n.

  Is there a good introduction to fft-multiplication algorithms as used in
  gmp on the web?

I don't know.  Hopefully smoebody else can answer.

--
Torbjörn