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
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
|
# isnanl.m4 serial 20
dnl Copyright (C) 2007-2018 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_FUNC_ISNANL],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
ISNANL_LIBM=
gl_HAVE_ISNANL_NO_LIBM
if test $gl_cv_func_isnanl_no_libm = no; then
gl_HAVE_ISNANL_IN_LIBM
if test $gl_cv_func_isnanl_in_libm = yes; then
ISNANL_LIBM=-lm
fi
fi
dnl The variable gl_func_isnanl set here is used by isnan.m4.
if test $gl_cv_func_isnanl_no_libm = yes \
|| test $gl_cv_func_isnanl_in_libm = yes; then
save_LIBS="$LIBS"
LIBS="$LIBS $ISNANL_LIBM"
gl_FUNC_ISNANL_WORKS
LIBS="$save_LIBS"
case "$gl_cv_func_isnanl_works" in
*yes) gl_func_isnanl=yes ;;
*) gl_func_isnanl=no; ISNANL_LIBM= ;;
esac
else
gl_func_isnanl=no
fi
if test $gl_func_isnanl != yes; then
HAVE_ISNANL=0
fi
AC_SUBST([ISNANL_LIBM])
])
AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM],
[
gl_HAVE_ISNANL_NO_LIBM
gl_func_isnanl_no_libm=$gl_cv_func_isnanl_no_libm
if test $gl_func_isnanl_no_libm = yes; then
gl_FUNC_ISNANL_WORKS
case "$gl_cv_func_isnanl_works" in
*yes) ;;
*) gl_func_isnanl_no_libm=no ;;
esac
fi
if test $gl_func_isnanl_no_libm = yes; then
AC_DEFINE([HAVE_ISNANL_IN_LIBC], [1],
[Define if the isnan(long double) function is available in libc.])
fi
])
dnl Prerequisites of replacement isnanl definition. It does not need -lm.
AC_DEFUN([gl_PREREQ_ISNANL],
[
gl_LONG_DOUBLE_EXPONENT_LOCATION
AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
])
dnl Test whether isnanl() can be used without libm.
AC_DEFUN([gl_HAVE_ISNANL_NO_LIBM],
[
AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm],
[gl_cv_func_isnanl_no_libm],
[
AC_LINK_IFELSE(
[AC_LANG_PROGRAM(
[[#include <math.h>
#if __GNUC__ >= 4
# undef isnanl
# define isnanl(x) __builtin_isnanl ((long double)(x))
#elif defined isnan
# undef isnanl
# define isnanl(x) isnan ((long double)(x))
#endif
long double x;]],
[[return isnanl (x);]])],
[gl_cv_func_isnanl_no_libm=yes],
[gl_cv_func_isnanl_no_libm=no])
])
])
dnl Test whether isnanl() can be used with libm.
AC_DEFUN([gl_HAVE_ISNANL_IN_LIBM],
[
AC_CACHE_CHECK([whether isnan(long double) can be used with libm],
[gl_cv_func_isnanl_in_libm],
[
save_LIBS="$LIBS"
LIBS="$LIBS -lm"
AC_LINK_IFELSE(
[AC_LANG_PROGRAM(
[[#include <math.h>
#if __GNUC__ >= 4
# undef isnanl
# define isnanl(x) __builtin_isnanl ((long double)(x))
#elif defined isnan
# undef isnanl
# define isnanl(x) isnan ((long double)(x))
#endif
long double x;]],
[[return isnanl (x);]])],
[gl_cv_func_isnanl_in_libm=yes],
[gl_cv_func_isnanl_in_libm=no])
LIBS="$save_LIBS"
])
])
dnl Test whether isnanl() recognizes all canonical numbers which are neither
dnl finite nor infinite.
AC_DEFUN([gl_FUNC_ISNANL_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([gl_BIGENDIAN])
AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether isnanl works], [gl_cv_func_isnanl_works],
[
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <float.h>
#include <limits.h>
#include <math.h>
#if __GNUC__ >= 4
# undef isnanl
# define isnanl(x) __builtin_isnanl ((long double)(x))
#elif defined isnan
# undef isnanl
# define isnanl(x) isnan ((long double)(x))
#endif
#define NWORDS \
((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { unsigned int word[NWORDS]; long double value; }
memory_long_double;
/* On Irix 6.5, gcc 3.4.3 can't compute compile-time NaN, and needs the
runtime type conversion. */
#ifdef __sgi
static long double NaNl ()
{
double zero = 0.0;
return zero / zero;
}
#else
# define NaNl() (0.0L / 0.0L)
#endif
int main ()
{
int result = 0;
if (!isnanl (NaNl ()))
result |= 1;
{
memory_long_double m;
unsigned int i;
/* The isnanl function should be immune against changes in the sign bit and
in the mantissa bits. The xor operation twiddles a bit that can only be
a sign bit or a mantissa bit (since the exponent never extends to
bit 31). */
m.value = NaNl ();
m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
for (i = 0; i < NWORDS; i++)
m.word[i] |= 1;
if (!isnanl (m.value))
result |= 1;
}
#if ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) && !HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
/* Representation of an 80-bit 'long double' as an initializer for a sequence
of 'unsigned int' words. */
# ifdef WORDS_BIGENDIAN
# define LDBL80_WORDS(exponent,manthi,mantlo) \
{ ((unsigned int) (exponent) << 16) | ((unsigned int) (manthi) >> 16), \
((unsigned int) (manthi) << 16) | ((unsigned int) (mantlo) >> 16), \
(unsigned int) (mantlo) << 16 \
}
# else
# define LDBL80_WORDS(exponent,manthi,mantlo) \
{ mantlo, manthi, exponent }
# endif
{ /* Quiet NaN. */
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0xC3333333, 0x00000000) };
if (!isnanl (x.value))
result |= 2;
}
{
/* Signalling NaN. */
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) };
if (!isnanl (x.value))
result |= 2;
}
/* isnanl should return something even for noncanonical values. */
{ /* Pseudo-NaN. */
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0x40000001, 0x00000000) };
if (isnanl (x.value) && !isnanl (x.value))
result |= 4;
}
{ /* Pseudo-Infinity. */
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) };
if (isnanl (x.value) && !isnanl (x.value))
result |= 8;
}
{ /* Pseudo-Zero. */
static memory_long_double x =
{ LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) };
if (isnanl (x.value) && !isnanl (x.value))
result |= 16;
}
{ /* Unnormalized number. */
static memory_long_double x =
{ LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) };
if (isnanl (x.value) && !isnanl (x.value))
result |= 32;
}
{ /* Pseudo-Denormal. */
static memory_long_double x =
{ LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) };
if (isnanl (x.value) && !isnanl (x.value))
result |= 64;
}
#endif
return result;
}]])],
[gl_cv_func_isnanl_works=yes],
[gl_cv_func_isnanl_works=no],
[case "$host_os" in
mingw*) # Guess yes on mingw, no on MSVC.
AC_EGREP_CPP([Known], [
#ifdef __MINGW32__
Known
#endif
],
[gl_cv_func_isnanl_works="guessing yes"],
[gl_cv_func_isnanl_works="guessing no"])
;;
*) gl_cv_func_isnanl_works="guessing yes" ;;
esac
])
])
])
|
