blob: af1800eeb889184033c98e5c7bb7582aed3f161d (
plain)
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
|
/* wf_exp.c -- float version of w_exp.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
* wrapper expf(x)
*/
#include "fdlibm.h"
#if __OBSOLETE_MATH
#include <errno.h>
#ifdef __STDC__
static const float
#else
static float
#endif
o_threshold= 8.8721679688e+01, /* 0x42b17180 */
u_threshold= -1.0397208405e+02; /* 0xc2cff1b5 */
#ifdef __STDC__
float expf(float x) /* wrapper expf */
#else
float expf(x) /* wrapper expf */
float x;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_expf(x);
#else
float z;
z = __ieee754_expf(x);
if(_LIB_VERSION == _IEEE_) return z;
if(finitef(x)) {
if(x>o_threshold) {
/* expf(finite) overflow */
#ifndef HUGE_VAL
#define HUGE_VAL inf
double inf = 0.0;
SET_HIGH_WORD(inf,0x7ff00000); /* set inf to infinite */
#endif
errno = ERANGE;
return HUGE_VAL;
} else if(x<u_threshold) {
/* expf(finite) underflow */
errno = ERANGE;
return 0.0f;
}
}
return z;
#endif
}
#ifdef _DOUBLE_IS_32BITS
#ifdef __STDC__
double exp(double x)
#else
double exp(x)
double x;
#endif
{
return (double) expf((float) x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */
#endif /* __OBSOLETE_MATH */
|
