flint-sys 0.9.0

Bindings to the FLINT C library
Documentation
/*
    Copyright (C) 2009, 2011 William Hart

    This file is part of FLINT.

    FLINT is free software: you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License (LGPL) as published
    by the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.  See <https://www.gnu.org/licenses/>.
*/

#include "test_helpers.h"
#include "mpn_extras.h"
#include "fft.h"

TEST_FUNCTION_START(mul_truncate_sqrt2, state)
{
    flint_bitcnt_t depth, w, maxdepth;

    maxdepth = (flint_test_multiplier() > 10) ? 12 :
               (flint_test_multiplier() > 1)  ? 11 : 10;

    for (depth = 6; depth <= maxdepth; depth++)
    {
        for (w = 1; w <= 5; w++)
        {
            mp_size_t n = (UWORD(1)<<depth);
            flint_bitcnt_t bits1 = (n*w - (depth + 1))/2;
            mp_size_t trunc = 2*n + 2*n_randint(state, n) + 2; /* trunc is even */
            flint_bitcnt_t bits = (trunc/2)*bits1;
            mp_size_t int_limbs = (bits - 1)/FLINT_BITS + 1;
            mp_size_t j;
            mp_limb_t * i1, *i2, *r1, *r2;

            i1 = flint_malloc(6*int_limbs*sizeof(mp_limb_t));
            i2 = i1 + int_limbs;
            r1 = i2 + int_limbs;
            r2 = r1 + 2*int_limbs;

            random_fermat(i1, state, int_limbs);
            random_fermat(i2, state, int_limbs);

            mpn_mul(r2, i1, int_limbs, i2, int_limbs);
            mul_truncate_sqrt2(r1, i1, int_limbs, i2, int_limbs, depth, w);

            for (j = 0; j < 2*int_limbs; j++)
            {
                if (r1[j] != r2[j])
                {
                    flint_printf("error in limb %wd, %wx != %wx\n", j, r1[j], r2[j]);
                    fflush(stdout);
                    flint_abort();
                }
            }

            flint_free(i1);
        }
    }

    /* test squaring */
    for (depth = 6; depth <= maxdepth; depth++)
    {
        for (w = 1; w <= 5; w++)
        {
            mp_size_t n = (UWORD(1)<<depth);
            flint_bitcnt_t bits1 = (n*w - (depth + 1))/2;
            mp_size_t trunc = 2*n + 2*n_randint(state, n) + 2; /* trunc is even */
            flint_bitcnt_t bits = (trunc/2)*bits1;
            mp_size_t int_limbs = (bits - 1)/FLINT_BITS + 1;
            mp_size_t j;
            mp_limb_t * i1, *r1, *r2;

            i1 = flint_malloc(5*int_limbs*sizeof(mp_limb_t));
            r1 = i1 + int_limbs;
            r2 = r1 + 2*int_limbs;

            random_fermat(i1, state, int_limbs);

            mpn_mul(r2, i1, int_limbs, i1, int_limbs);
            mul_truncate_sqrt2(r1, i1, int_limbs, i1, int_limbs, depth, w);

            for (j = 0; j < 2*int_limbs; j++)
            {
                if (r1[j] != r2[j])
                {
                    flint_printf("error in limb %wd, %wx != %wx\n", j, r1[j], r2[j]);
                    fflush(stdout);
                    flint_abort();
                }
            }

            flint_free(i1);
        }
    }

    TEST_FUNCTION_END(state);
}