1/* Test file for mpfr_d_sub
2
3Copyright 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4Contributed by the Arenaire and Cacao projects, INRIA.
5
6This file is part of the GNU MPFR Library.
7
8The GNU MPFR Library is free software; you can redistribute it and/or modify
9it under the terms of the GNU Lesser General Public License as published by
10the Free Software Foundation; either version 3 of the License, or (at your
11option) any later version.
12
13The GNU MPFR Library is distributed in the hope that it will be useful, but
14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
16License for more details.
17
18You should have received a copy of the GNU Lesser General Public License
19along with the GNU MPFR Library; see the file COPYING.LESSER.  If not, see
20http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
2151 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
22
23#include <stdio.h>
24#include <stdlib.h>
25#include <float.h>
26
27#include "mpfr-test.h"
28
29#if MPFR_VERSION >= MPFR_VERSION_NUM(2,4,0)
30
31static void
32check_nans (void)
33{
34  mpfr_t  x, y;
35  int inexact;
36
37  mpfr_init2 (x, 123);
38  mpfr_init2 (y, 123);
39
40  /* 1.0 - nan is nan */
41  mpfr_set_nan (x);
42  mpfr_clear_flags ();
43  inexact = mpfr_d_sub (y, 1.0, x, MPFR_RNDN);
44  MPFR_ASSERTN (inexact == 0);
45  MPFR_ASSERTN ((__gmpfr_flags ^ MPFR_FLAGS_NAN) == 0);
46  MPFR_ASSERTN (mpfr_nan_p (y));
47
48  /* 1.0 - +inf == -inf */
49  mpfr_set_inf (x, 1);
50  mpfr_clear_flags ();
51  inexact = mpfr_d_sub (y, 1.0, x, MPFR_RNDN);
52  MPFR_ASSERTN (inexact == 0);
53  MPFR_ASSERTN (__gmpfr_flags == 0);
54  MPFR_ASSERTN (mpfr_inf_p (y));
55  MPFR_ASSERTN (MPFR_IS_NEG (y));
56
57  /* 1.0 - -inf == +inf */
58  mpfr_set_inf (x, -1);
59  mpfr_clear_flags ();
60  inexact = mpfr_d_sub (y, 1.0, x, MPFR_RNDN);
61  MPFR_ASSERTN (inexact == 0);
62  MPFR_ASSERTN (__gmpfr_flags == 0);
63  MPFR_ASSERTN (mpfr_inf_p (y));
64  MPFR_ASSERTN (MPFR_IS_POS (y));
65
66  mpfr_clear (x);
67  mpfr_clear (y);
68}
69
70#define TEST_FUNCTION mpfr_d_sub
71#define DOUBLE_ARG1
72#define RAND_FUNCTION(x) mpfr_random2(x, MPFR_LIMB_SIZE (x), 1, RANDS)
73#include "tgeneric.c"
74
75int
76main (void)
77{
78  mpfr_t x, y, z;
79  double d;
80  int inexact;
81
82  tests_start_mpfr ();
83
84  /* check with enough precision */
85  mpfr_init2 (x, IEEE_DBL_MANT_DIG);
86  mpfr_init2 (y, IEEE_DBL_MANT_DIG);
87  mpfr_init2 (z, IEEE_DBL_MANT_DIG);
88
89  mpfr_set_str (y, "4096", 10, MPFR_RNDN);
90  d = 0.125;
91  mpfr_clear_flags ();
92  inexact = mpfr_d_sub (x, d, y, MPFR_RNDN);
93  if (inexact != 0)
94    {
95      printf ("Inexact flag error in mpfr_d_sub\n");
96      exit (1);
97    }
98  mpfr_set_str (z, "-4095.875", 10, MPFR_RNDN);
99  if (mpfr_cmp (z, x))
100    {
101      printf ("Error in mpfr_d_sub (");
102      mpfr_out_str (stdout, 10, 7, y, MPFR_RNDN);
103      printf (" + %.20g)\nexpected ", d);
104      mpfr_out_str (stdout, 10, 0, z, MPFR_RNDN);
105      printf ("\ngot     ");
106      mpfr_out_str (stdout, 10, 0, x, MPFR_RNDN);
107      printf ("\n");
108      exit (1);
109    }
110  mpfr_clears (x, y, z, (mpfr_ptr) 0);
111
112  check_nans ();
113
114  test_generic (2, 1000, 100);
115
116  tests_end_mpfr ();
117  return 0;
118}
119
120#else
121
122int
123main (void)
124{
125  printf ("Warning! Test disabled for this MPFR version.\n");
126  return 0;
127}
128
129#endif
130