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 2, or (at your option)
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, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
18 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */
28 #define ASSERT(expr) \
33 fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
41 long double zerol = 0.0L;
47 ASSERT (!signbit (3.141f));
48 ASSERT (!signbit (3.141e30f));
49 ASSERT (!signbit (3.141e-30f));
50 ASSERT (signbit (-2.718f));
51 ASSERT (signbit (-2.718e30f));
52 ASSERT (signbit (-2.718e-30f));
53 /* Infinite values. */
54 ASSERT (!signbit (1.0f / 0.0f));
55 ASSERT (signbit (-1.0f / 0.0f));
57 (void) signbit (zerof / zerof);
58 #if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
62 ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
63 typedef union { float value; unsigned int word[NWORDS]; } memory_float;
65 m.value = zerof / zerof;
66 # if FLT_EXPBIT0_BIT > 0
67 m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
69 m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
70 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
72 if (FLT_EXPBIT0_WORD < NWORDS / 2)
73 m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
75 m.word[0] |= (unsigned int) 1;
76 (void) signbit (m.value);
86 ASSERT (!signbit (3.141));
87 ASSERT (!signbit (3.141e30));
88 ASSERT (!signbit (3.141e-30));
89 ASSERT (signbit (-2.718));
90 ASSERT (signbit (-2.718e30));
91 ASSERT (signbit (-2.718e-30));
92 /* Infinite values. */
93 ASSERT (!signbit (1.0 / 0.0));
94 ASSERT (signbit (-1.0 / 0.0));
96 (void) signbit (zerod / zerod);
97 #if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
101 ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
102 typedef union { double value; unsigned int word[NWORDS]; } memory_double;
104 m.value = zerod / zerod;
105 # if DBL_EXPBIT0_BIT > 0
106 m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
108 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
109 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
111 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
112 |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
113 (void) signbit (m.value);
123 ASSERT (!signbit (3.141L));
124 ASSERT (!signbit (3.141e30L));
125 ASSERT (!signbit (3.141e-30L));
126 ASSERT (signbit (-2.718L));
127 ASSERT (signbit (-2.718e30L));
128 ASSERT (signbit (-2.718e-30L));
129 /* Infinite values. */
130 ASSERT (!signbit (1.0L / 0.0L));
131 ASSERT (signbit (-1.0L / 0.0L));
133 (void) signbit (zerol / zerol);
134 #if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT
135 /* Signalling NaN. */
138 ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
139 typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double;
140 memory_long_double m;
141 m.value = zerol / zerol;
142 # if LDBL_EXPBIT0_BIT > 0
143 m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1);
145 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
146 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
148 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
149 |= (unsigned int) 1 << LDBL_EXPBIT0_BIT;
150 (void) signbit (m.value);