pqc/external/flint-2.4.3/fmpz_mod_poly/sqr.c

72 lines
2.1 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 Sebastian Pancratz
Copyright (C) 2010 William Hart
******************************************************************************/
#include <gmp.h>
#include "flint.h"
#include "fmpz.h"
#include "fmpz_poly.h"
#include "fmpz_mod_poly.h"
void _fmpz_mod_poly_sqr(fmpz *res, const fmpz *poly, slong len, const fmpz_t p)
{
_fmpz_poly_sqr(res, poly, len);
_fmpz_vec_scalar_mod_fmpz(res, res, 2 * len - 1, p);
}
void fmpz_mod_poly_sqr(fmpz_mod_poly_t res, const fmpz_mod_poly_t poly)
{
const slong len = poly->length;
if (len == 0)
{
fmpz_mod_poly_zero(res);
return;
}
if (res == poly)
{
fmpz *t = flint_calloc(2 * len - 1, sizeof(fmpz));
_fmpz_mod_poly_sqr(t, poly->coeffs, len, &(res->p));
_fmpz_vec_clear(res->coeffs, res->alloc);
res->alloc = 2 * len - 1;
res->length = 2 * len - 1;
res->coeffs = t;
_fmpz_mod_poly_normalise(res);
}
else
{
fmpz_mod_poly_fit_length(res, 2 * len - 1);
_fmpz_mod_poly_sqr(res->coeffs, poly->coeffs, len, &(res->p));
_fmpz_mod_poly_set_length(res, 2 * len - 1);
_fmpz_mod_poly_normalise(res);
}
}