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

160 lines
3.9 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) 2009 William Hart
******************************************************************************/
#include <stdlib.h>
#include <gmp.h>
#include "flint.h"
#include "fmpz.h"
/* Always free larger mpz's to avoid wasting too much heap space */
#define FLINT_MPZ_MAX_CACHE_LIMBS 64
/* The number of new mpz's allocated at a time */
#define MPZ_BLOCK 64
FLINT_TLS_PREFIX __mpz_struct ** mpz_free_arr = NULL;
FLINT_TLS_PREFIX ulong mpz_free_num = 0;
FLINT_TLS_PREFIX ulong mpz_free_alloc = 0;
__mpz_struct * _fmpz_new_mpz(void)
{
if (mpz_free_num != 0)
{
return mpz_free_arr[--mpz_free_num];
}
else
{
__mpz_struct * z = flint_malloc(sizeof(__mpz_struct));
mpz_init(z);
return z;
}
}
void _fmpz_clear_mpz(fmpz f)
{
__mpz_struct * ptr = COEFF_TO_PTR(f);
if (ptr->_mp_alloc > FLINT_MPZ_MAX_CACHE_LIMBS)
mpz_realloc2(ptr, 1);
if (mpz_free_num == mpz_free_alloc)
{
mpz_free_alloc = FLINT_MAX(64, mpz_free_alloc * 2);
mpz_free_arr = flint_realloc(mpz_free_arr, mpz_free_alloc * sizeof(__mpz_struct *));
}
mpz_free_arr[mpz_free_num++] = ptr;
}
void _fmpz_cleanup_mpz_content(void)
{
ulong i;
for (i = 0; i < mpz_free_num; i++)
{
mpz_clear(mpz_free_arr[i]);
flint_free(mpz_free_arr[i]);
}
mpz_free_num = mpz_free_alloc = 0;
}
void _fmpz_cleanup(void)
{
_fmpz_cleanup_mpz_content();
flint_free(mpz_free_arr);
mpz_free_arr = NULL;
}
__mpz_struct * _fmpz_promote(fmpz_t f)
{
if (!COEFF_IS_MPZ(*f)) /* f is small so promote it first */
{
__mpz_struct * mpz_ptr = _fmpz_new_mpz();
(*f) = PTR_TO_COEFF(mpz_ptr);
return mpz_ptr;
}
else /* f is large already, just return the pointer */
return COEFF_TO_PTR(*f);
}
__mpz_struct * _fmpz_promote_val(fmpz_t f)
{
fmpz c = (*f);
if (!COEFF_IS_MPZ(c)) /* f is small so promote it */
{
__mpz_struct * mpz_ptr = _fmpz_new_mpz();
(*f) = PTR_TO_COEFF(mpz_ptr);
flint_mpz_set_si(mpz_ptr, c);
return mpz_ptr;
}
else /* f is large already, just return the pointer */
return COEFF_TO_PTR(c);
}
void _fmpz_demote_val(fmpz_t f)
{
__mpz_struct * mpz_ptr = COEFF_TO_PTR(*f);
int size = mpz_ptr->_mp_size;
if (size == 1 || size == -1)
{
ulong uval = mpz_ptr->_mp_d[0];
if (uval <= (ulong) COEFF_MAX)
{
_fmpz_clear_mpz(*f);
*f = size * (fmpz) uval;
}
}
else if (size == 0) /* value is 0 */
{
_fmpz_clear_mpz(*f);
*f = 0;
}
/* don't do anything if value has to be multi precision */
}
void _fmpz_init_readonly_mpz(fmpz_t f, const mpz_t z)
{
__mpz_struct *ptr;
*f = WORD(0);
ptr = _fmpz_promote(f);
mpz_clear(ptr);
*ptr = *z;
}
void _fmpz_clear_readonly_mpz(mpz_t z)
{
if (((z->_mp_size == 1 || z->_mp_size == -1) && (z->_mp_d[0] <= COEFF_MAX))
|| (z->_mp_size == 0))
{
mpz_clear(z);
}
}