1 /* Test of signbit() substitute.
2 Copyright (C) 2007, 2008 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */
27 #define ASSERT(expr) \
32 fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
40 long double zerol = 0.0L;
46 ASSERT (!signbit (3.141f));
47 ASSERT (!signbit (3.141e30f));
48 ASSERT (!signbit (3.141e-30f));
49 ASSERT (signbit (-2.718f));
50 ASSERT (signbit (-2.718e30f));
51 ASSERT (signbit (-2.718e-30f));
53 ASSERT (!signbit (0.0f));
54 if (1.0f / -zerof < 0)
55 ASSERT (signbit (-0.0f));
57 ASSERT (!signbit (-0.0f));
58 /* Infinite values. */
59 ASSERT (!signbit (1.0f / 0.0f));
60 ASSERT (signbit (-1.0f / 0.0f));
62 (void) signbit (zerof / zerof);
63 #if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
67 ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
68 typedef union { float value; unsigned int word[NWORDS]; } memory_float;
70 m.value = zerof / zerof;
71 # if FLT_EXPBIT0_BIT > 0
72 m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
74 m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
75 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
77 if (FLT_EXPBIT0_WORD < NWORDS / 2)
78 m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
80 m.word[0] |= (unsigned int) 1;
81 (void) signbit (m.value);
91 ASSERT (!signbit (3.141));
92 ASSERT (!signbit (3.141e30));
93 ASSERT (!signbit (3.141e-30));
94 ASSERT (signbit (-2.718));
95 ASSERT (signbit (-2.718e30));
96 ASSERT (signbit (-2.718e-30));
98 ASSERT (!signbit (0.0));
100 ASSERT (signbit (-0.0));
102 ASSERT (!signbit (-0.0));
103 /* Infinite values. */
104 ASSERT (!signbit (1.0 / 0.0));
105 ASSERT (signbit (-1.0 / 0.0));
107 (void) signbit (zerod / zerod);
108 #if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
109 /* Signalling NaN. */
112 ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
113 typedef union { double value; unsigned int word[NWORDS]; } memory_double;
115 m.value = zerod / zerod;
116 # if DBL_EXPBIT0_BIT > 0
117 m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
119 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
120 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
122 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
123 |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
124 (void) signbit (m.value);
134 ASSERT (!signbit (3.141L));
135 ASSERT (!signbit (3.141e30L));
136 ASSERT (!signbit (3.141e-30L));
137 ASSERT (signbit (-2.718L));
138 ASSERT (signbit (-2.718e30L));
139 ASSERT (signbit (-2.718e-30L));
141 ASSERT (!signbit (0.0L));
142 if (1.0L / -zerol < 0)
143 ASSERT (signbit (-0.0L));
145 ASSERT (!signbit (-0.0L));
146 /* Infinite values. */
147 ASSERT (!signbit (1.0L / 0.0L));
148 ASSERT (signbit (-1.0L / 0.0L));
150 (void) signbit (zerol / zerol);
151 #if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT
152 /* Signalling NaN. */
155 ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
156 typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double;
157 memory_long_double m;
158 m.value = zerol / zerol;
159 # if LDBL_EXPBIT0_BIT > 0
160 m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1);
162 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
163 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
165 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
166 |= (unsigned int) 1 << LDBL_EXPBIT0_BIT;
167 (void) signbit (m.value);