Jacobi/Legendre/Kronecker

bodrato at mail.dm.unipi.it bodrato at mail.dm.unipi.it
Thu Dec 20 09:38:11 CET 2012


Ciao Niels, ciao Paul!

Il Lun, 17 Dicembre 2012 9:07 pm, Niels Möller ha scritto:
> Zimmermann Paul <Paul.Zimmermann at loria.fr> writes:
>> frite% gcc -I$GMP/include -O2 -g e.c $GMP/lib/libgmp.a
>> frite% ./a.out
>> GMP: header 5.0.5, library 5.0.5
>> mpz_jacobi:       408ms

>> frite% gcc -I/tmp/include -O2 -g e.c /tmp/lib/libgmp.a
>> frite% ./a.out
>> GMP: header 5.1.0, library 5.1.0
>> mpz_jacobi:       536ms

>> Apparently we have a noticeable regression...

> I don't have the time to investigate carefully right now, but some
> comments:

I tested some changes and I suggest the attached patch: unconditionally
reduce modulo b.

Niels, can you check if it makes sense?
Paul, can you measure if it reduce the regression?

Best regards,
m

-- 
http://bodrato.it/papers/
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