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authorMarco Bodrato <bodrato@mail.dm.unipi.it>2018-11-10 14:13:27 +0100
committerMarco Bodrato <bodrato@mail.dm.unipi.it>2018-11-10 14:13:27 +0100
commit97dabcd884e62f455c2ada2fdd79d329f56ad389 (patch)
tree0454d4b1eb11978f64637c9af0704d8814a7aa8d /tests
parent03518052e5266e8df9d25c556c9c5bb8f1deec7f (diff)
downloadgmp-97dabcd884e62f455c2ada2fdd79d329f56ad389.tar.gz
tests/mpz/t-lucm.c: New test, for the internal function mpz_lucas_mod
Diffstat (limited to 'tests')
-rw-r--r--tests/mpz/Makefile.am2
-rw-r--r--tests/mpz/t-lucm.c144
2 files changed, 145 insertions, 1 deletions
diff --git a/tests/mpz/Makefile.am b/tests/mpz/Makefile.am
index b178acef3..6a56edac6 100644
--- a/tests/mpz/Makefile.am
+++ b/tests/mpz/Makefile.am
@@ -26,7 +26,7 @@ check_PROGRAMS = reuse t-addsub t-cmp t-mul t-mul_i t-tdiv t-tdiv_ui t-fdiv \
t-fdiv_ui t-cdiv_ui t-gcd t-gcd_ui t-lcm t-invert dive dive_ui t-sqrtrem \
convert io t-inp_str logic bit t-powm t-powm_ui t-pow t-div_2exp \
t-root t-perfsqr t-perfpow t-jac t-bin t-get_d t-get_d_2exp t-get_si \
- t-set_d t-set_si \
+ t-set_d t-set_si t-lucm \
t-fac_ui t-mfac_uiui t-primorial_ui t-fib_ui t-lucnum_ui t-scan t-fits \
t-divis t-divis_2exp t-cong t-cong_2exp t-sizeinbase t-set_str \
t-aorsmul t-cmp_d t-cmp_si t-hamdist t-oddeven t-popcount t-set_f \
diff --git a/tests/mpz/t-lucm.c b/tests/mpz/t-lucm.c
new file mode 100644
index 000000000..3b6dcd1b5
--- /dev/null
+++ b/tests/mpz/t-lucm.c
@@ -0,0 +1,144 @@
+/* Test mpz_powm, mpz_lucas_mod.
+
+Copyright 1991, 1993, 1994, 1996, 1999-2001, 2009, 2012, 2018 Free Software
+Foundation, Inc.
+
+This file is part of the GNU MP Library test suite.
+
+The GNU MP Library test suite 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 3 of the License,
+or (at your option) any later version.
+
+The GNU MP Library test suite 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
+the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "gmp-impl.h"
+#include "tests.h"
+
+void debug_mp (mpz_t, int);
+
+#define SIZEM 8
+
+/* FIXME: Should we implement another sequence to test lucas mod? */
+/* Eg: a generalisation of what we use for Fibonacci: */
+/* U_{2n-1} = U_n^2 - Q*U_{n-1}^2 */
+/* U_{2n+1} = D*U_n^2 + Q*U_{2n-1} + 2*Q^n ; whith D = (P^2-4*Q) */
+/* P*U_{2n} = U_{2n+1} + Q*U_{2n-1} */
+
+int
+main (int argc, char **argv)
+{
+ mpz_t base, exp, mod;
+ mpz_t r1, r2, t1, t2;
+ mp_size_t base_size, exp_size, mod_size;
+ int i, res;
+ int reps = 1000;
+ long Q;
+ gmp_randstate_ptr rands;
+ mpz_t bs;
+ unsigned long bsi, size_range;
+
+ tests_start ();
+ TESTS_REPS (reps, argv, argc);
+
+ rands = RANDS;
+
+ mpz_init (bs);
+
+ mpz_init (base);
+ mpz_init (exp);
+ mpz_init (mod);
+ mpz_init (r1);
+ mpz_init (r2);
+ mpz_init (t1);
+ mpz_init (t2);
+
+ for (i = 0; i < reps; i++)
+ {
+ mpz_urandomb (bs, rands, 32);
+ size_range = mpz_get_ui (bs) % SIZEM + 1;
+
+ do /* Loop until base >= 2 and fits in a long. */
+ {
+ mpz_urandomb (base, rands, BITS_PER_ULONG - 2);
+ }
+ while (mpz_cmp_ui (base, 2) < 0 || mpz_fits_slong_p (base) == 0);
+
+ Q = mpz_get_ui (base);
+
+ do
+ {
+ ++size_range;
+ size_range = MIN (size_range, SIZEM);
+ mpz_urandomb (bs, rands, size_range);
+ mod_size = mpz_get_ui (bs);
+ mpz_rrandomb (mod, rands, mod_size);
+ mpz_add_ui (mod, mod, 16);
+ }
+ while (mpz_gcd_ui (NULL, mod, Q) != 1);
+
+ mod_size = mpz_sizeinbase (mod, 2) - 3;
+ mpz_urandomb (bs, rands, 32);
+ exp_size = mpz_get_ui (bs) % mod_size + 2;
+
+ mpz_tdiv_q_2exp (exp, mod, exp_size);
+ mpz_add_ui (exp, exp, 1);
+
+ mpz_urandomb (bs, rands, 2);
+ bsi = mpz_get_ui (bs);
+ if ((bsi & 1) != 0)
+ {
+ mpz_neg (base, base);
+ Q = -Q;
+ }
+
+ res = mpz_lucas_mod (t1, r2, Q, exp_size, mod, t2, r1);
+ if (res && ++reps)
+ continue;
+ MPZ_CHECK_FORMAT (r2);
+ if (mpz_cmp_ui (r2, 0) < 0)
+ mpz_add (r2, r2, mod);
+ mpz_powm (r1, base, exp, mod);
+
+ if (mpz_cmp (r1, r2) != 0)
+ {
+ fprintf (stderr, "\nIncorrect results in test %d for operands:\n", i);
+ debug_mp (base, -16);
+ debug_mp (exp, -16);
+ debug_mp (mod, -16);
+ fprintf (stderr, "mpz_powm result:\n");
+ debug_mp (r1, -16);
+ fprintf (stderr, "mpz_lucas_mod result (%d) Q=%ld:\n", res, Q);
+ debug_mp (r2, -16);
+ abort ();
+ }
+ }
+
+ mpz_clear (bs);
+ mpz_clear (base);
+ mpz_clear (exp);
+ mpz_clear (mod);
+ mpz_clear (r1);
+ mpz_clear (r2);
+ mpz_clear (t1);
+ mpz_clear (t2);
+
+ tests_end ();
+ exit (0);
+}
+
+void
+debug_mp (mpz_t x, int base)
+{
+ mpz_out_str (stderr, base, x); fputc ('\n', stderr);
+}