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/*
Copyright (C) 2022 Daniel Schultz
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 "gmpcompat.h"
#include "mpn_extras.h"
#include "fft.h"
/* Defined in t-adjust.c, t-adjust_sqrt2.c, t-butterfly.c, t-butterfly_lshB.c,
* t-butterfly_rshB.c, t-butterfly_sqrt2.c, t-butterfly_twiddle.c,
* t-div_2expmod_2expp1.c, t-mul_2expmod_2expp1.c, t-negmod_2expp1.c,
* t-normmod_2expp1.c */
#ifndef set_p
#define set_p set_p
/* set p = 2^wn + 1 */
void set_p(mpz_t p, mp_size_t n, flint_bitcnt_t w)
{
flint_mpz_set_ui(p, 1);
mpz_mul_2exp(p, p, n*w);
flint_mpz_add_ui(p, p, 1);
}
#endif
TEST_FUNCTION_START(mpn_negmod_2expp1, state)
{
flint_bitcnt_t bits;
mp_size_t j, k, n, w, limbs;
mp_limb_t * a, * z;
mpz_t p, z1, z2;
mpz_init(z1);
mpz_init(z2);
mpz_init(p);
/* normalisation mod p = 2^wn + 1 where B divides nw and n is a power of 2 */
for (bits = FLINT_BITS; bits < 16*FLINT_BITS; bits += FLINT_BITS)
{
for (j = 1; j < 32; j++)
{
for (k = 1; k <= FLINT_BITS; k <<= 1)
{
n = bits/k;
w = j*k;
limbs = (n*w)/GMP_LIMB_BITS;
set_p(p, n, w);
a = flint_malloc((limbs + 1)*sizeof(mp_limb_t));
z = flint_malloc((limbs + 1)*sizeof(mp_limb_t));
random_fermat(a, state, limbs);
mpn_normmod_2expp1(a, limbs);
mpn_negmod_2expp1(z, a, limbs);
fermat_to_mpz(z1, a, limbs);
mpz_neg(z1, z1);
mpz_mod(z1, z1, p);
fermat_to_mpz(z2, z, limbs);
if (mpz_cmp(z1, z2) != 0)
{
flint_printf("FAIL:\n");
flint_printf("mpn_negmod_2expp1 error\n");
gmp_printf("want %Zx\n\n", z1);
gmp_printf("got %Zx\n", z2);
fflush(stdout);
flint_abort();
}
flint_free(a);
flint_free(z);
}
}
}
mpz_clear(p);
mpz_clear(z2);
mpz_clear(z1);
TEST_FUNCTION_END(state);
}