pqc/external/flint-2.4.3/fq_poly_templates/mulmod.c
2014-05-24 23:16:06 +02:00

118 lines
3.5 KiB
C

/*=============================================================================
This file is part of FLINT.
FLINT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
FLINT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with FLINT; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2011 Fredrik Johansson
Copyright (C) 2012 Lina Kulakova
Copyright (C) 2013 Mike Hansen
******************************************************************************/
#ifdef T
#include "templates.h"
void
_TEMPLATE(T, poly_mulmod) (TEMPLATE(T, struct) * res,
const TEMPLATE(T, struct) * poly1, slong len1,
const TEMPLATE(T, struct) * poly2, slong len2,
const TEMPLATE(T, struct) * f, slong lenf,
const TEMPLATE(T, ctx_t) ctx)
{
TEMPLATE(T, struct) * T, *Q;
TEMPLATE(T, t) invf;
slong lenT, lenQ;
lenT = len1 + len2 - 1;
lenQ = lenT - lenf + 1;
T = _TEMPLATE(T, vec_init) (lenT + lenQ, ctx);
Q = T + lenT;
if (len1 >= len2)
_TEMPLATE(T, poly_mul) (T, poly1, len1, poly2, len2, ctx);
else
_TEMPLATE(T, poly_mul) (T, poly2, len2, poly1, len1, ctx);
TEMPLATE(T, init) (invf, ctx);
TEMPLATE(T, inv) (invf, f + lenf - 1, ctx);
_TEMPLATE(T, poly_divrem) (Q, res, T, lenT, f, lenf, invf, ctx);
_TEMPLATE(T, vec_clear) (T, lenT + lenQ, ctx);
TEMPLATE(T, clear) (invf, ctx);
}
void
TEMPLATE(T, poly_mulmod) (TEMPLATE(T, poly_t) res,
const TEMPLATE(T, poly_t) poly1,
const TEMPLATE(T, poly_t) poly2,
const TEMPLATE(T, poly_t) f,
const TEMPLATE(T, ctx_t) ctx)
{
slong len1, len2, lenf;
TEMPLATE(T, struct) * fcoeffs;
lenf = f->length;
len1 = poly1->length;
len2 = poly2->length;
if (lenf == 0)
{
TEMPLATE_PRINTF("Exception: %s_poly_mulmod: divide by zero\n", T);
abort();
}
if (lenf == 1 || len1 == 0 || len2 == 0)
{
TEMPLATE(T, poly_zero) (res, ctx);
return;
}
if (len1 + len2 - lenf > 0)
{
if (f == res)
{
fcoeffs = _TEMPLATE(T, vec_init) (lenf, ctx);
_TEMPLATE(T, vec_set) (fcoeffs, f->coeffs, lenf, ctx);
}
else
fcoeffs = f->coeffs;
TEMPLATE(T, poly_fit_length) (res, len1 + len2 - 1, ctx);
_TEMPLATE(T, poly_mulmod) (res->coeffs,
poly1->coeffs, len1,
poly2->coeffs, len2, fcoeffs, lenf, ctx);
if (f == res)
_TEMPLATE(T, vec_clear) (fcoeffs, lenf, ctx);
_TEMPLATE(T, poly_set_length) (res, lenf - 1, ctx);
_TEMPLATE(T, poly_normalise) (res, ctx);
}
else
{
TEMPLATE(T, poly_mul) (res, poly1, poly2, ctx);
}
}
#endif