t-fdiv_ui.c revision 1.1.1.3 
1/* Test mpz_abs, mpz_add, mpz_cmp, mpz_cmp_ui, mpz_fdiv_qr_ui, mpz_fdiv_q_ui,
2   mpz_fdiv_r_ui, mpz_fdiv_ui, mpz_mul_ui.
3
4Copyright 1993, 1994, 1996, 2000-2002 Free Software Foundation, Inc.
5
6This file is part of the GNU MP Library test suite.
7
8The GNU MP Library test suite is free software; you can redistribute it
9and/or modify it under the terms of the GNU General Public License as
10published by the Free Software Foundation; either version 3 of the License,
11or (at your option) any later version.
12
13The GNU MP Library test suite is distributed in the hope that it will be
14useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
15MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
16Public License for more details.
17
18You should have received a copy of the GNU General Public License along with
19the GNU MP Library test suite.  If not, see https://www.gnu.org/licenses/.  */
20
21#include <stdio.h>
22#include <stdlib.h>
23
24#include "gmp.h"
25#include "gmp-impl.h"
26#include "tests.h"
27
28void dump_abort (const char *, mpz_t, unsigned long);
29void debug_mp (mpz_t, int);
30
31int
32main (int argc, char **argv)
33{
34  mpz_t dividend;
35  mpz_t quotient, remainder;
36  mpz_t quotient2, remainder2;
37  mpz_t temp;
38  mp_size_t dividend_size;
39  unsigned long divisor;
40  int i;
41  int reps = 10000;
42  gmp_randstate_ptr rands;
43  mpz_t bs;
44  unsigned long bsi, size_range;
45  unsigned long r_rq, r_q, r_r, r;
46
47  tests_start ();
48  rands = RANDS;
49
50  mpz_init (bs);
51
52  if (argc == 2)
53     reps = atoi (argv[1]);
54
55  mpz_init (dividend);
56  mpz_init (quotient);
57  mpz_init (remainder);
58  mpz_init (quotient2);
59  mpz_init (remainder2);
60  mpz_init (temp);
61
62  for (i = 0; i < reps; i++)
63    {
64      mpz_urandomb (bs, rands, 32);
65      size_range = mpz_get_ui (bs) % 10 + 2; /* 0..2047 bit operands */
66
67      do
68	{
69	  mpz_rrandomb (bs, rands, 64);
70	  divisor = mpz_get_ui (bs);
71	}
72      while (divisor == 0);
73
74      mpz_urandomb (bs, rands, size_range);
75      dividend_size = mpz_get_ui (bs);
76      mpz_rrandomb (dividend, rands, dividend_size);
77
78      mpz_urandomb (bs, rands, 2);
79      bsi = mpz_get_ui (bs);
80      if ((bsi & 1) != 0)
81	mpz_neg (dividend, dividend);
82
83      /* printf ("%ld\n", SIZ (dividend)); */
84
85      r_rq = mpz_fdiv_qr_ui (quotient, remainder, dividend, divisor);
86      r_q = mpz_fdiv_q_ui (quotient2, dividend, divisor);
87      r_r = mpz_fdiv_r_ui (remainder2, dividend, divisor);
88      r = mpz_fdiv_ui (dividend, divisor);
89
90      /* First determine that the quotients and remainders computed
91	 with different functions are equal.  */
92      if (mpz_cmp (quotient, quotient2) != 0)
93	dump_abort ("quotients from mpz_fdiv_qr_ui and mpz_fdiv_q_ui differ",
94		    dividend, divisor);
95      if (mpz_cmp (remainder, remainder2) != 0)
96	dump_abort ("remainders from mpz_fdiv_qr_ui and mpz_fdiv_r_ui differ",
97		    dividend, divisor);
98
99      /* Check if the sign of the quotient is correct.  */
100      if (mpz_cmp_ui (quotient, 0) != 0)
101	if ((mpz_cmp_ui (quotient, 0) < 0)
102	    != (mpz_cmp_ui (dividend, 0) < 0))
103	dump_abort ("quotient sign wrong", dividend, divisor);
104
105      /* Check if the remainder has the same sign as the (positive) divisor
106	 (quotient rounded towards minus infinity).  */
107      if (mpz_cmp_ui (remainder, 0) != 0)
108	if (mpz_cmp_ui (remainder, 0) < 0)
109	  dump_abort ("remainder sign wrong", dividend, divisor);
110
111      mpz_mul_ui (temp, quotient, divisor);
112      mpz_add (temp, temp, remainder);
113      if (mpz_cmp (temp, dividend) != 0)
114	dump_abort ("n mod d != n - [n/d]*d", dividend, divisor);
115
116      mpz_abs (remainder, remainder);
117      if (mpz_cmp_ui (remainder, divisor) >= 0)
118	dump_abort ("remainder greater than divisor", dividend, divisor);
119
120      if (mpz_cmp_ui (remainder, r_rq) != 0)
121	dump_abort ("remainder returned from mpz_fdiv_qr_ui is wrong",
122		    dividend, divisor);
123      if (mpz_cmp_ui (remainder, r_q) != 0)
124	dump_abort ("remainder returned from mpz_fdiv_q_ui is wrong",
125		    dividend, divisor);
126      if (mpz_cmp_ui (remainder, r_r) != 0)
127	dump_abort ("remainder returned from mpz_fdiv_r_ui is wrong",
128		    dividend, divisor);
129      if (mpz_cmp_ui (remainder, r) != 0)
130	dump_abort ("remainder returned from mpz_fdiv_ui is wrong",
131		    dividend, divisor);
132    }
133
134  mpz_clear (bs);
135  mpz_clear (dividend);
136  mpz_clear (quotient);
137  mpz_clear (remainder);
138  mpz_clear (quotient2);
139  mpz_clear (remainder2);
140  mpz_clear (temp);
141
142  tests_end ();
143  exit (0);
144}
145
146void
147dump_abort (const char *str, mpz_t dividend, unsigned long divisor)
148{
149  fprintf (stderr, "ERROR: %s\n", str);
150  fprintf (stderr, "dividend = "); debug_mp (dividend, -16);
151  fprintf (stderr, "divisor  = %lX\n", divisor);
152  abort();
153}
154
155void
156debug_mp (mpz_t x, int base)
157{
158  mpz_out_str (stderr, base, x); fputc ('\n', stderr);
159}
160