91 lines
2.4 KiB
C
91 lines
2.4 KiB
C
/*=============================================================================
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This file is part of FLINT.
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FLINT is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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FLINT is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with FLINT; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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=============================================================================*/
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/******************************************************************************
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Copyright (C) 2009 William Hart
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******************************************************************************/
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#include <stdio.h>
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#include <stdlib.h>
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#include <gmp.h>
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#include "flint.h"
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#include "ulong_extras.h"
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int main(void)
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{
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int i, result;
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FLINT_TEST_INIT(state);
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flint_printf("powmod2_preinv....");
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fflush(stdout);
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for (i = 0; i < 10000 * flint_test_multiplier(); i++)
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{
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mp_limb_t a, d, r1, r2, dinv;
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mpz_t a_m, d_m, r2_m;
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mp_limb_signed_t exp;
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mpz_init(a_m);
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mpz_init(d_m);
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mpz_init(r2_m);
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d = n_randtest_not_zero(state);
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do
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{
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a = n_randtest(state) % d;
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} while (n_gcd(d, a) != UWORD(1));
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exp = n_randtest(state);
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dinv = n_preinvert_limb(d);
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r1 = n_powmod2_preinv(a, exp, d, dinv);
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flint_mpz_set_ui(a_m, a);
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flint_mpz_set_ui(d_m, d);
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if (exp < WORD(0))
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{
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flint_mpz_powm_ui(r2_m, a_m, -exp, d_m);
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mpz_invert(r2_m, r2_m, d_m);
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} else
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flint_mpz_powm_ui(r2_m, a_m, exp, d_m);
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r2 = flint_mpz_get_ui(r2_m);
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result = (r1 == r2);
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if (!result)
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{
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flint_printf("FAIL:\n");
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flint_printf("a = %wu, exp = %wd, d = %wu\n", a, exp, d);
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flint_printf("r1 = %wu, r2 = %wu\n", r1, r2);
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abort();
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}
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mpz_clear(a_m);
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mpz_clear(d_m);
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mpz_clear(r2_m);
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}
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FLINT_TEST_CLEANUP(state);
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flint_printf("PASS\n");
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return 0;
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}
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