summaryrefslogtreecommitdiff
path: root/tests/test-signbit.c
blob: 97f68e6a71b2d323478b07d6328d52066e6e6aca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/* Test of signbit() substitute.
   Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc.

   This program 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.

   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Written by Bruno Haible <bruno@clisp.org>, 2007.  */

#include <config.h>

#include <math.h>

#include <float.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>

#define ASSERT(expr) \
  do									     \
    {									     \
      if (!(expr))							     \
        {								     \
          fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
          fflush (stderr);						     \
          abort ();							     \
        }								     \
    }									     \
  while (0)

float zerof = 0.0f;
double zerod = 0.0;
long double zerol = 0.0L;

/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0f.
   So we use -zerof instead.  */

/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
   So we use -zerod instead.  */

/* On HP-UX 10.20, negating 0.0L does not yield -0.0L.
   So we use minus_zerol instead.
   IRIX cc can't put -0.0L into .data, but can compute at runtime.
   Note that the expression -LDBL_MIN * LDBL_MIN does not work on other
   platforms, such as when cross-compiling to PowerPC on MacOS X 10.5.  */
#if defined __hpux || defined __sgi
static long double
compute_minus_zerol (void)
{
  return -LDBL_MIN * LDBL_MIN;
}
# define minus_zerol compute_minus_zerol ()
#else
long double minus_zerol = -0.0L;
#endif

static void
test_signbitf ()
{
  /* Finite values.  */
  ASSERT (!signbit (3.141f));
  ASSERT (!signbit (3.141e30f));
  ASSERT (!signbit (3.141e-30f));
  ASSERT (signbit (-2.718f));
  ASSERT (signbit (-2.718e30f));
  ASSERT (signbit (-2.718e-30f));
  /* Zeros.  */
  ASSERT (!signbit (0.0f));
  if (1.0f / -zerof < 0)
    ASSERT (signbit (-zerof));
  else
    ASSERT (!signbit (-zerof));
  /* Infinite values.  */
  ASSERT (!signbit (1.0f / 0.0f));
  ASSERT (signbit (-1.0f / 0.0f));
  /* Quiet NaN.  */
  (void) signbit (zerof / zerof);
#if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
  /* Signalling NaN.  */
  {
    #define NWORDS \
      ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
    typedef union { float value; unsigned int word[NWORDS]; } memory_float;
    memory_float m;
    m.value = zerof / zerof;
# if FLT_EXPBIT0_BIT > 0
    m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
# else
    m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
      ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
    if (FLT_EXPBIT0_WORD < NWORDS / 2)
      m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
    else
      m.word[0] |= (unsigned int) 1;
    (void) signbit (m.value);
    #undef NWORDS
  }
#endif
}

static void
test_signbitd ()
{
  /* Finite values.  */
  ASSERT (!signbit (3.141));
  ASSERT (!signbit (3.141e30));
  ASSERT (!signbit (3.141e-30));
  ASSERT (signbit (-2.718));
  ASSERT (signbit (-2.718e30));
  ASSERT (signbit (-2.718e-30));
  /* Zeros.  */
  ASSERT (!signbit (0.0));
  if (1.0 / -zerod < 0)
    ASSERT (signbit (-zerod));
  else
    ASSERT (!signbit (-zerod));
  /* Infinite values.  */
  ASSERT (!signbit (1.0 / 0.0));
  ASSERT (signbit (-1.0 / 0.0));
  /* Quiet NaN.  */
  (void) signbit (zerod / zerod);
#if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
  /* Signalling NaN.  */
  {
    #define NWORDS \
      ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
    typedef union { double value; unsigned int word[NWORDS]; } memory_double;
    memory_double m;
    m.value = zerod / zerod;
# if DBL_EXPBIT0_BIT > 0
    m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
# else
    m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
      ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
    m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
      |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
    (void) signbit (m.value);
    #undef NWORDS
  }
#endif
}

static void
test_signbitl ()
{
  /* Finite values.  */
  ASSERT (!signbit (3.141L));
  ASSERT (!signbit (3.141e30L));
  ASSERT (!signbit (3.141e-30L));
  ASSERT (signbit (-2.718L));
  ASSERT (signbit (-2.718e30L));
  ASSERT (signbit (-2.718e-30L));
  /* Zeros.  */
  ASSERT (!signbit (0.0L));
  if (1.0L / minus_zerol < 0)
    ASSERT (signbit (minus_zerol));
  else
    ASSERT (!signbit (minus_zerol));
  /* Infinite values.  */
  ASSERT (!signbit (1.0L / 0.0L));
  ASSERT (signbit (-1.0L / 0.0L));
  /* Quiet NaN.  */
  (void) signbit (zerol / zerol);
#if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT
  /* Signalling NaN.  */
  {
    #define NWORDS \
      ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
    typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double;
    memory_long_double m;
    m.value = zerol / zerol;
# if LDBL_EXPBIT0_BIT > 0
    m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1);
# else
    m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
      ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
    m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
      |= (unsigned int) 1 << LDBL_EXPBIT0_BIT;
    (void) signbit (m.value);
    #undef NWORDS
  }
#endif
}

int
main ()
{
  test_signbitf ();
  test_signbitd ();
  test_signbitl ();
  return 0;
}