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
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
|
/***********************************************************************
** File: fpmacros.c
**
** Contains: C source code for implementations of floating-point
** functions which involve float format numbers, as
** defined in header <fp.h>. In particular, this file
** contains implementations of functions
** __fpclassify(d,f), __isnormal(d,f), __isfinite(d,f),
** __isnan(d,f), and __signbit(d,f). This file targets
** PowerPC platforms.
**
** Written by: Robert A. Murley, Ali Sazegari
**
** Copyright: c 2001 by Apple Computer, Inc., all rights reserved
**
** Change History (most recent first):
**
** 07 Jul 01 ram First created from fpfloatfunc.c, fp.c,
** classify.c and sign.c in MathLib v3 Mac OS9.
**
***********************************************************************/
#include <features.h>
#include <sys/types.h>
#include <math.h>
#include "fp_private.h"
#define SIGN_MASK 0x80000000
#define NSIGN_MASK 0x7fffffff
#define FEXP_MASK 0x7f800000
#define FFRAC_MASK 0x007fffff
/***********************************************************************
int __fpclassifyf(float x) returns the classification code of the
argument x, as defined in <fp.h>.
Exceptions: INVALID signaled if x is a signaling NaN; in this case,
the FP_QNAN code is returned.
Calls: none
***********************************************************************/
int __fpclassifyf ( float x )
{
unsigned int iexp;
union {
u_int32_t lval;
float fval;
} z;
z.fval = x;
iexp = z.lval & FEXP_MASK; /* isolate float exponent */
if (iexp == FEXP_MASK) { /* NaN or INF case */
if ((z.lval & 0x007fffff) == 0)
return FP_INFINITE;
return FP_NAN;
}
if (iexp != 0) /* normal float */
return FP_NORMAL;
if (x == 0.0)
return FP_ZERO; /* zero */
else
return FP_SUBNORMAL; /* must be subnormal */
}
/***********************************************************************
Function __fpclassify,
Implementation of classify of a double number for the PowerPC.
Exceptions: INVALID signaled if x is a signaling NaN; in this case,
the FP_QNAN code is returned.
Calls: none
***********************************************************************/
int __fpclassify ( double arg )
{
register unsigned int exponent;
union
{
dHexParts hex;
double dbl;
} x;
x.dbl = arg;
exponent = x.hex.high & dExpMask;
if ( exponent == dExpMask )
{
if ( ( ( x.hex.high & dHighMan ) | x.hex.low ) == 0 )
return FP_INFINITE;
else
return FP_NAN;
}
else if ( exponent != 0)
return FP_NORMAL;
else {
if ( arg == 0.0 )
return FP_ZERO;
else
return FP_SUBNORMAL;
}
}
/***********************************************************************
int __isnormalf(float x) returns nonzero if and only if x is a
normalized float number and zero otherwise.
Exceptions: INVALID is raised if x is a signaling NaN; in this case,
zero is returned.
Calls: none
***********************************************************************/
int __isnormalf ( float x )
{
unsigned int iexp;
union {
u_int32_t lval;
float fval;
} z;
z.fval = x;
iexp = z.lval & FEXP_MASK; /* isolate float exponent */
return ((iexp != FEXP_MASK) && (iexp != 0));
}
int __isnormal ( double x )
{
return ( __fpclassify ( x ) == FP_NORMAL );
}
/***********************************************************************
int __isfinitef(float x) returns nonzero if and only if x is a
finite (normal, subnormal, or zero) float number and zero otherwise.
Exceptions: INVALID is raised if x is a signaling NaN; in this case,
zero is returned.
Calls: none
***********************************************************************/
int __finitef ( float x )
{
union {
u_int32_t lval;
float fval;
} z;
z.fval = x;
return ((z.lval & FEXP_MASK) != FEXP_MASK);
}
weak_alias (__finitef, finitef)
#if 0 /* use __finite in s_finite.c */
int __finite ( double x )
{
return ( __fpclassify ( x ) >= FP_ZERO );
}
weak_alias (__finite, finite)
#endif
/***********************************************************************
int __signbitf(float x) returns nonzero if and only if the sign
bit of x is set and zero otherwise.
Exceptions: INVALID is raised if x is a signaling NaN.
Calls: none
***********************************************************************/
int __signbitf ( float x )
{
union {
u_int32_t lval;
float fval;
} z;
z.fval = x;
return ((z.lval & SIGN_MASK) != 0);
}
/***********************************************************************
Function sign of a double.
Implementation of sign bit for the PowerPC.
Calls: none
***********************************************************************/
int __signbit ( double arg )
{
union
{
dHexParts hex;
double dbl;
} x;
int sign;
x.dbl = arg;
sign = ( ( x.hex.high & dSgnMask ) == dSgnMask ) ? 1 : 0;
return sign;
}
/***********************************************************************
* int __isinff(float x) returns -1 if value represents negative
* infinity, 1 if value represents positive infinity,
* and 0 otherwise.
*
* Calls: __signbit
* +***********************************************************************/
int __isinff ( float x )
{
int class = __fpclassifyf(x);
if ( class == FP_INFINITE ) {
return ( (__signbitf(x)) ? -1 : 1);
}
return 0;
}
weak_alias (__isinff, isinff)
int __isinf ( double x )
{
int class = __fpclassify(x);
if ( class == FP_INFINITE ) {
return ( (__signbit(x)) ? -1 : 1);
}
return 0;
}
weak_alias (__isinf, isinf)
#if 0
int __isinfl ( long double x )
{
int class = __fpclassify(x);
if ( class == FP_INFINITE ) {
return ( (__signbit(x)) ? -1 : 1);
}
return 0;
}
weak_alias (__isinfl, isinfl);
#endif
/***********************************************************************
int __isnanf(float x) returns nonzero if and only if x is a
NaN and zero otherwise.
Exceptions: INVALID is raised if x is a signaling NaN; in this case,
nonzero is returned.
Calls: none
***********************************************************************/
int __isnanf ( float x )
{
union {
u_int32_t lval;
float fval;
} z;
z.fval = x;
return (((z.lval&FEXP_MASK) == FEXP_MASK) && ((z.lval&FFRAC_MASK) != 0));
}
weak_alias (__isnanf, isnanf);
int __isnan ( double x )
{
int class = __fpclassify(x);
return ( class == FP_NAN );
}
weak_alias (__isnan, isnan);
#if 0
int __isnanl ( long double x )
{
int class = __fpclassify(x);
return ( class == FP_NAN );
}
weak_alias (__isnanl, isnanl);
#endif
|
