pqc/external/flint-2.4.3/fq_poly_factor_templates/factor.c

233 lines
7.7 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) 2007 David Howden
Copyright (C) 2007, 2008, 2009, 2010 William Hart
Copyright (C) 2008 Richard Howell-Peak
Copyright (C) 2011 Fredrik Johansson
Copyright (C) 2013 Mike Hansen
******************************************************************************/
#ifdef T
#include "templates.h"
#define ZASSENHAUS 0
#define BERLEKAMP 1
#define KALTOFEN 2
static __inline__ void
__TEMPLATE(T, poly_factor1) (TEMPLATE(T, poly_factor_t) res,
const TEMPLATE(T, poly_t) f, int algorithm,
const TEMPLATE(T, ctx_t) ctx)
{
if (algorithm == KALTOFEN)
TEMPLATE(T, poly_factor_kaltofen_shoup) (res, f, ctx);
else if (algorithm == ZASSENHAUS)
TEMPLATE(T, poly_factor_cantor_zassenhaus) (res, f, ctx);
else
TEMPLATE(T, poly_factor_berlekamp) (res, f, ctx);
}
void
__TEMPLATE(T, poly_factor) (TEMPLATE(T, poly_factor_t) result,
TEMPLATE(T, t) leading_coeff,
const TEMPLATE(T, poly_t) input,
int algorithm, const TEMPLATE(T, ctx_t) ctx)
{
TEMPLATE(T, poly_t) monic_input;
TEMPLATE(T, poly_factor_t) sqfree_factors, factors;
slong i, len;
len = input->length;
if (len <= 1)
{
if (len == 0)
{
TEMPLATE(T, zero) (leading_coeff, ctx);
return;
}
else
{
TEMPLATE(T, set) (leading_coeff, input->coeffs, ctx);
}
}
TEMPLATE(T, poly_get_coeff) (leading_coeff, input,
TEMPLATE(T, poly_degree) (input, ctx), ctx);
TEMPLATE(T, poly_init) (monic_input, ctx);
TEMPLATE(T, poly_make_monic) (monic_input, input, ctx);
if (len == 2)
{
TEMPLATE(T, poly_factor_insert) (result, monic_input, 1, ctx);
TEMPLATE(T, poly_clear) (monic_input, ctx);
TEMPLATE(T, set) (leading_coeff, input->coeffs + 1, ctx);
return;
}
TEMPLATE(T, poly_factor_init) (sqfree_factors, ctx);
TEMPLATE(T, poly_factor_squarefree) (sqfree_factors, monic_input, ctx);
TEMPLATE(T, poly_clear) (monic_input, ctx);
/* Run CZ on each of the square-free factors */
for (i = 0; i < sqfree_factors->num; i++)
{
TEMPLATE(T, poly_factor_init) (factors, ctx);
__TEMPLATE(T, poly_factor1) (factors, sqfree_factors->poly + i,
algorithm, ctx);
TEMPLATE(T, poly_factor_pow) (factors, sqfree_factors->exp[i], ctx);
TEMPLATE(T, poly_factor_concat) (result, factors, ctx);
TEMPLATE(T, poly_factor_clear) (factors, ctx);
}
TEMPLATE(T, poly_factor_clear) (sqfree_factors, ctx);
return;
}
void
__TEMPLATE(T, poly_factor_deflation) (TEMPLATE(T, poly_factor_t) result,
TEMPLATE(T, t) leading_coeff,
const TEMPLATE(T, poly_t) input,
int algorithm,
const TEMPLATE(T, ctx_t) ctx)
{
slong i;
ulong deflation;
if (input->length <= 1)
{
if (input->length == 0)
{
TEMPLATE(T, zero) (leading_coeff, ctx);
return;
}
else
{
TEMPLATE(T, set) (leading_coeff, input->coeffs, ctx);
return;
}
}
deflation = TEMPLATE(T, poly_deflation) (input, ctx);
if (deflation == 1)
{
__TEMPLATE(T, poly_factor) (result, leading_coeff, input, algorithm,
ctx);
return;
}
else
{
TEMPLATE(T, poly_factor_t) def_res;
TEMPLATE(T, poly_t) def;
TEMPLATE(T, poly_init) (def, ctx);
TEMPLATE(T, poly_deflate) (def, input, deflation, ctx);
TEMPLATE(T, poly_factor_init) (def_res, ctx);
__TEMPLATE(T, poly_factor) (def_res, leading_coeff, def, algorithm,
ctx);
TEMPLATE(T, poly_clear) (def, ctx);
for (i = 0; i < def_res->num; i++)
{
/* Inflate */
TEMPLATE(T, poly_t) pol;
TEMPLATE(T, poly_init) (pol, ctx);
TEMPLATE(T, poly_inflate) (pol, def_res->poly + i, deflation, ctx);
/* Factor inflation */
if (def_res->exp[i] == 1)
__TEMPLATE(T, poly_factor) (result, leading_coeff, pol,
algorithm, ctx);
else
{
TEMPLATE(T, poly_factor_t) t;
TEMPLATE(T, poly_factor_init) (t, ctx);
__TEMPLATE(T, poly_factor) (t, leading_coeff, pol, algorithm,
ctx);
TEMPLATE(T, poly_factor_pow) (t, def_res->exp[i], ctx);
TEMPLATE(T, poly_factor_concat) (result, t, ctx);
TEMPLATE(T, poly_factor_clear) (t, ctx);
}
TEMPLATE(T, poly_clear) (pol, ctx);
}
TEMPLATE(T, poly_factor_clear) (def_res, ctx);
}
}
void
TEMPLATE(T, poly_factor_with_berlekamp) (TEMPLATE(T, poly_factor_t) result,
TEMPLATE(T, t) leading_coeff,
const TEMPLATE(T, poly_t) input,
const TEMPLATE(T, ctx_t) ctx)
{
__TEMPLATE(T, poly_factor_deflation) (result, leading_coeff, input,
BERLEKAMP, ctx);
}
void
TEMPLATE(T, poly_factor_with_cantor_zassenhaus) (
TEMPLATE(T, poly_factor_t) result,
TEMPLATE(T, t) leading_coeff,
const TEMPLATE(T, poly_t) input,
const TEMPLATE(T, ctx_t) ctx)
{
__TEMPLATE(T, poly_factor_deflation) (result, leading_coeff, input,
ZASSENHAUS, ctx);
}
void
TEMPLATE(T, poly_factor_with_kaltofen_shoup) (
TEMPLATE(T, poly_factor_t) result,
TEMPLATE(T, t) leading_coeff,
const TEMPLATE(T, poly_t) input,
const TEMPLATE(T, ctx_t) ctx)
{
__TEMPLATE(T, poly_factor_deflation) (result, leading_coeff, input,
KALTOFEN, ctx);
}
void
TEMPLATE(T, poly_factor) (TEMPLATE(T, poly_factor_t) result,
TEMPLATE(T, t) leading_coeff,
const TEMPLATE(T, poly_t) input,
const TEMPLATE(T, ctx_t) ctx)
{
mp_bitcnt_t bits = fmpz_bits(TEMPLATE(T, ctx_prime) (ctx));
slong n = TEMPLATE(T, poly_degree) (input, ctx);
if (n < 10 + 50 / bits)
__TEMPLATE(T, poly_factor_deflation) (result, leading_coeff, input,
ZASSENHAUS, ctx);
else
__TEMPLATE(T, poly_factor_deflation) (result, leading_coeff, input,
KALTOFEN, ctx);
}
#endif