xref: /netbsd-src/external/lgpl3/gmp/dist/tests/mpn/t-minvert.c (revision 72c7faa4dbb41dbb0238d6b4a109da0d4b236dd4)
1 /* Copyright 2013-2015 Free Software Foundation, Inc.
2 
3 This file is part of the GNU MP Library test suite.
4 
5 The GNU MP Library test suite is free software; you can redistribute it
6 and/or modify it under the terms of the GNU General Public License as
7 published by the Free Software Foundation; either version 3 of the License,
8 or (at your option) any later version.
9 
10 The GNU MP Library test suite is distributed in the hope that it will be
11 useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
13 Public License for more details.
14 
15 You should have received a copy of the GNU General Public License along with
16 the GNU MP Library test suite.  If not, see https://www.gnu.org/licenses/.  */
17 
18 #include <stdio.h>
19 #include <stdlib.h>		/* for strtol */
20 
21 #include "gmp-impl.h"
22 #include "longlong.h"
23 #include "tests/tests.h"
24 
25 #define MAX_SIZE 50
26 
27 #define COUNT 200
28 
29 static void
mpz_to_mpn(mp_ptr ap,mp_size_t an,const mpz_t b)30 mpz_to_mpn (mp_ptr ap, mp_size_t an, const mpz_t b)
31 {
32   mp_size_t bn = mpz_size (b);
33   ASSERT_ALWAYS (bn <= an);
34   MPN_COPY_INCR (ap, mpz_limbs_read (b), bn);
35   MPN_ZERO (ap + bn, an - bn);
36 }
37 
38 int
mpz_eq_mpn(mp_ptr ap,mp_size_t an,const mpz_t b)39 mpz_eq_mpn (mp_ptr ap, mp_size_t an, const mpz_t b)
40 {
41   mp_size_t bn = mpz_size (b);
42 
43   return (bn >= 0 && bn <= an
44 	  && mpn_cmp (ap, mpz_limbs_read (b), bn) == 0
45 	  && (an == bn || mpn_zero_p (ap + bn, an - bn)));
46 }
47 
48 static mp_bitcnt_t
bit_size(mp_srcptr xp,mp_size_t n)49 bit_size (mp_srcptr xp, mp_size_t n)
50 {
51   MPN_NORMALIZE (xp, n);
52   return n > 0 ? mpn_sizeinbase (xp, n, 2) : 0;
53 }
54 
55 int
main(int argc,char ** argv)56 main (int argc, char **argv)
57 {
58   gmp_randstate_ptr rands;
59   long count = COUNT;
60   mp_ptr mp;
61   mp_ptr ap;
62   mp_ptr tp;
63   mp_ptr scratch;
64   mpz_t m, a, r, g;
65   int test;
66   mp_limb_t ran;
67   mp_size_t itch;
68   TMP_DECL;
69 
70   tests_start ();
71   rands = RANDS;
72 
73 
74   TMP_MARK;
75   mpz_init (m);
76   mpz_init (a);
77   mpz_init (r);
78   mpz_init (g);
79 
80   TESTS_REPS (count, argv, argc);
81 
82   mp = TMP_ALLOC_LIMBS (MAX_SIZE);
83   ap = TMP_ALLOC_LIMBS (MAX_SIZE);
84   tp = TMP_ALLOC_LIMBS (MAX_SIZE);
85   scratch = TMP_ALLOC_LIMBS (mpn_sec_invert_itch (MAX_SIZE) + 1);
86 
87   for (test = 0; test < count; test++)
88     {
89       mp_bitcnt_t bits;
90       int rres, tres;
91       mp_size_t n;
92 
93       bits = urandom () % (GMP_NUMB_BITS * MAX_SIZE) + 1;
94 
95       if (test & 1)
96 	mpz_rrandomb (m, rands, bits);
97       else
98 	mpz_urandomb (m, rands, bits);
99       if (test & 2)
100 	mpz_rrandomb (a, rands, bits);
101       else
102 	mpz_urandomb (a, rands, bits);
103 
104       mpz_setbit (m, 0);
105       if (test & 4)
106 	{
107 	  /* Ensure it really is invertible */
108 	  if (mpz_sgn (a) == 0)
109 	    mpz_set_ui (a, 1);
110 	  else
111 	    for (;;)
112 	      {
113 		mpz_gcd (g, a, m);
114 		if (mpz_cmp_ui (g, 1) == 0)
115 		  break;
116 		mpz_remove (a, a, g);
117 	      }
118 	}
119 
120       rres = mpz_invert (r, a, m);
121       if ( (test & 4) && !rres)
122 	{
123 	  gmp_fprintf (stderr, "test %d: Not invertible!\n"
124 		       "m = %Zd\n"
125 		       "a = %Zd\n", test, m, a);
126 	  abort ();
127 	}
128       ASSERT_ALWAYS (! (test & 4) || rres);
129 
130       n = (bits + GMP_NUMB_BITS - 1) / GMP_NUMB_BITS;
131       ASSERT_ALWAYS (n <= MAX_SIZE);
132       itch = mpn_sec_invert_itch (n);
133       scratch[itch] = ran = urandom ();
134 
135       mpz_to_mpn (ap, n, a);
136       mpz_to_mpn (mp, n, m);
137       tres = mpn_sec_invert (tp, ap, mp, n,
138 			     bit_size (ap, n) + bit_size (mp, n),
139 			     scratch);
140 
141       if (rres != tres || (rres == 1 && !mpz_eq_mpn (tp, n, r)) || ran != scratch[itch])
142 	{
143 	  gmp_fprintf (stderr, "Test %d failed.\n"
144 		       "m = %Zd\n"
145 		       "a = %Zd\n", test, m, a);
146 	  fprintf (stderr, "ref ret: %d\n"
147 		  "got ret: %d\n", rres, tres);
148 	  if (rres)
149 	    gmp_fprintf (stderr, "ref: %Zd\n", r);
150 	  if (tres)
151 	    gmp_fprintf (stderr, "got: %Nd\n", tp, n);
152 	  if (ran != scratch[itch])
153 	    fprintf (stderr, "scratch[itch] changed.\n");
154 	  abort ();
155 	}
156     }
157 
158   TMP_FREE;
159 
160   mpz_clear (m);
161   mpz_clear (a);
162   mpz_clear (r);
163   mpz_clear (g);
164 
165   tests_end ();
166   return 0;
167 }
168