1 /* Test of signbit() substitute.
2 Copyright (C) 2007 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));
52 /* Infinite values. */
53 ASSERT (!signbit (1.0f / 0.0f));
54 ASSERT (signbit (-1.0f / 0.0f));
56 (void) signbit (zerof / zerof);
57 #if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
61 ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
62 typedef union { float value; unsigned int word[NWORDS]; } memory_float;
64 m.value = zerof / zerof;
65 # if FLT_EXPBIT0_BIT > 0
66 m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
68 m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
69 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
71 if (FLT_EXPBIT0_WORD < NWORDS / 2)
72 m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
74 m.word[0] |= (unsigned int) 1;
75 (void) signbit (m.value);
85 ASSERT (!signbit (3.141));
86 ASSERT (!signbit (3.141e30));
87 ASSERT (!signbit (3.141e-30));
88 ASSERT (signbit (-2.718));
89 ASSERT (signbit (-2.718e30));
90 ASSERT (signbit (-2.718e-30));
91 /* Infinite values. */
92 ASSERT (!signbit (1.0 / 0.0));
93 ASSERT (signbit (-1.0 / 0.0));
95 (void) signbit (zerod / zerod);
96 #if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
100 ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
101 typedef union { double value; unsigned int word[NWORDS]; } memory_double;
103 m.value = zerod / zerod;
104 # if DBL_EXPBIT0_BIT > 0
105 m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
107 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
108 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
110 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
111 |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
112 (void) signbit (m.value);
122 ASSERT (!signbit (3.141L));
123 ASSERT (!signbit (3.141e30L));
124 ASSERT (!signbit (3.141e-30L));
125 ASSERT (signbit (-2.718L));
126 ASSERT (signbit (-2.718e30L));
127 ASSERT (signbit (-2.718e-30L));
128 /* Infinite values. */
129 ASSERT (!signbit (1.0L / 0.0L));
130 ASSERT (signbit (-1.0L / 0.0L));
132 (void) signbit (zerol / zerol);
133 #if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT
134 /* Signalling NaN. */
137 ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
138 typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double;
139 memory_long_double m;
140 m.value = zerol / zerol;
141 # if LDBL_EXPBIT0_BIT > 0
142 m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1);
144 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
145 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
147 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
148 |= (unsigned int) 1 << LDBL_EXPBIT0_BIT;
149 (void) signbit (m.value);