summaryrefslogtreecommitdiff
path: root/math/test-math-iszero.cc
blob: d0417bec692716a04ca797b9a1dd8c27d8ba4fec (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
/* Test for the C++ implementation of iszero.
   Copyright (C) 2016-2018 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#define _GNU_SOURCE 1
#include <math.h>
#include <stdio.h>

#include <limits>

/* Support for _Float128 in std::numeric_limits is limited.
   Include ieee754_float128.h and use the bitfields in the union
   ieee854_float128.ieee_nan to build corner-case inputs.  */
#if __HAVE_DISTINCT_FLOAT128
# include <ieee754_float128.h>
#endif

static bool errors;

static void
check (int actual, int expected, const char *actual_expr, int line)
{
  if (actual != expected)
    {
      errors = true;
      printf ("%s:%d: error: %s\n", __FILE__, line, actual_expr);
      printf ("%s:%d:   expected: %d\n", __FILE__, line, expected);
      printf ("%s:%d:   actual: %d\n", __FILE__, line, actual);
    }
}

#define CHECK(actual, expected) \
  check ((actual), (expected), #actual, __LINE__)

template <class T>
static void
check_type ()
{
  typedef std::numeric_limits<T> limits;
  CHECK (iszero (T{}), 1);
  CHECK (iszero (T{0}), 1);
  CHECK (iszero (T{-0.0}), 1);
  CHECK (iszero (T{1}), 0);
  CHECK (iszero (T{-1}), 0);
  CHECK (iszero (limits::min ()), 0);
  CHECK (iszero (-limits::min ()), 0);
  CHECK (iszero (limits::max ()), 0);
  CHECK (iszero (-limits::max ()), 0);
  if (limits::has_infinity)
    {
      CHECK (iszero (limits::infinity ()), 0);
      CHECK (iszero (-limits::infinity ()), 0);
    }
  CHECK (iszero (limits::epsilon ()), 0);
  CHECK (iszero (-limits::epsilon ()), 0);
  if (limits::has_quiet_NaN)
    CHECK (iszero (limits::quiet_NaN ()), 0);
  if (limits::has_signaling_NaN)
    CHECK (iszero (limits::signaling_NaN ()), 0);
  if (limits::has_signaling_NaN)
    CHECK (iszero (limits::signaling_NaN ()), 0);
  CHECK (iszero (limits::denorm_min ()),
         std::numeric_limits<T>::has_denorm == std::denorm_absent);
  CHECK (iszero (-limits::denorm_min ()),
         std::numeric_limits<T>::has_denorm == std::denorm_absent);
}

#if __HAVE_DISTINCT_FLOAT128
static void
check_float128 ()
{
  ieee854_float128 q;

  q.d = 0.0Q;
  CHECK (iszero (q.d), 1);
  q.d = -0.0Q;
  CHECK (iszero (q.d), 1);
  q.d = 1.0Q;
  CHECK (iszero (q.d), 0);
  q.d = -1.0Q;
  CHECK (iszero (q.d), 0);

  /* Normal min.  */
  q.ieee.negative = 0;
  q.ieee.exponent = 0x0001;
  q.ieee.mantissa0 = 0x0000;
  q.ieee.mantissa1 = 0x00000000;
  q.ieee.mantissa2 = 0x00000000;
  q.ieee.mantissa3 = 0x00000000;
  CHECK (iszero (q.d), 0);
  q.ieee.negative = 1;
  CHECK (iszero (q.d), 0);

  /* Normal max.  */
  q.ieee.negative = 0;
  q.ieee.exponent = 0x7FFE;
  q.ieee.mantissa0 = 0xFFFF;
  q.ieee.mantissa1 = 0xFFFFFFFF;
  q.ieee.mantissa2 = 0xFFFFFFFF;
  q.ieee.mantissa3 = 0xFFFFFFFF;
  CHECK (iszero (q.d), 0);
  q.ieee.negative = 1;
  CHECK (iszero (q.d), 0);

  /* Infinity.  */
  q.ieee.negative = 0;
  q.ieee.exponent = 0x7FFF;
  q.ieee.mantissa0 = 0x0000;
  q.ieee.mantissa1 = 0x00000000;
  q.ieee.mantissa2 = 0x00000000;
  q.ieee.mantissa3 = 0x00000000;
  CHECK (iszero (q.d), 0);

  /* Quiet NaN.  */
  q.ieee_nan.quiet_nan = 1;
  q.ieee_nan.mantissa0 = 0x0000;
  CHECK (iszero (q.d), 0);

  /* Signaling NaN.  */
  q.ieee_nan.quiet_nan = 0;
  q.ieee_nan.mantissa0 = 0x4000;
  CHECK (iszero (q.d), 0);

  /* Denormal min.  */
  q.ieee.negative = 0;
  q.ieee.exponent = 0x0000;
  q.ieee.mantissa0 = 0x0000;
  q.ieee.mantissa1 = 0x00000000;
  q.ieee.mantissa2 = 0x00000000;
  q.ieee.mantissa3 = 0x00000001;
  CHECK (iszero (q.d), 0);
  q.ieee.negative = 1;
  CHECK (iszero (q.d), 0);
}
#endif

static int
do_test (void)
{
  check_type<float> ();
  check_type<double> ();
  check_type<long double> ();
#if __HAVE_DISTINCT_FLOAT128
  check_float128 ();
#endif
  return errors;
}

#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"