1 /* wf_scalb.c -- float version of w_scalb.c.
2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3  */
4 
5 /*
6  * ====================================================
7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8  *
9  * Developed at SunPro, a Sun Microsystems, Inc. business.
10  * Permission to use, copy, modify, and distribute this
11  * software is freely granted, provided that this notice
12  * is preserved.
13  * ====================================================
14  */
15 
16 /*
17  * wrapper scalbf(float x, float fn) is provide for
18  * passing various standard test suite. One
19  * should use scalbn() instead.
20  */
21 
22 #include "fdlibm.h"
23 #include <errno.h>
24 
25 #ifdef __STDC__
26 #ifdef _SCALB_INT
scalbf(float x,int fn)27 	float scalbf(float x, int fn)		/* wrapper scalbf */
28 #else
29 	float scalbf(float x, float fn)		/* wrapper scalbf */
30 #endif
31 #else
32 	float scalbf(x,fn)			/* wrapper scalbf */
33 #ifdef _SCALB_INT
34 	float x; int fn;
35 #else
36 	float x,fn;
37 #endif
38 #endif
39 {
40 #ifdef _IEEE_LIBM
41 	return __ieee754_scalbf(x,fn);
42 #else
43 	float z;
44 #ifndef HUGE_VAL
45 #define HUGE_VAL inf
46 	double inf = 0.0;
47 
48 	SET_HIGH_WORD(inf,0x7ff00000);	/* set inf to infinite */
49 #endif
50 	struct exception exc;
51 	z = __ieee754_scalbf(x,fn);
52 	if(_LIB_VERSION == _IEEE_) return z;
53 	if(!(finitef(z)||isnanf(z))&&finitef(x)) {
54 	    /* scalbf overflow; SVID also returns +-HUGE_VAL */
55 	    exc.type = OVERFLOW;
56 	    exc.name = "scalbf";
57 	    exc.err = 0;
58 	    exc.arg1 = (double)x;
59 	    exc.arg2 = (double)fn;
60 	    exc.retval = x > 0.0 ? HUGE_VAL : -HUGE_VAL;
61 	    if (_LIB_VERSION == _POSIX_)
62 	       errno = ERANGE;
63 	    else if (!matherr(&exc)) {
64 	       errno = ERANGE;
65 	    }
66 	    if (exc.err != 0)
67 	       errno = exc.err;
68             return exc.retval;
69 	}
70 	if(z==(float)0.0&&z!=x) {
71 	    /* scalbf underflow */
72 	    exc.type = UNDERFLOW;
73 	    exc.name = "scalbf";
74 	    exc.err = 0;
75 	    exc.arg1 = (double)x;
76 	    exc.arg2 = (double)fn;
77 	    exc.retval = copysign(0.0,x);
78 	    if (_LIB_VERSION == _POSIX_)
79 	       errno = ERANGE;
80 	    else if (!matherr(&exc)) {
81 	       errno = ERANGE;
82 	    }
83 	    if (exc.err != 0)
84 	       errno = exc.err;
85             return exc.retval;
86 	}
87 #ifndef _SCALB_INT
88 	if(!finitef(fn)) errno = ERANGE;
89 #endif
90 	return z;
91 #endif
92 }
93 
94 #ifdef _DOUBLE_IS_32BITS
95 
96 #ifdef __STDC__
97 #ifdef _SCALB_INT
scalb(double x,int fn)98 	double scalb(double x, int fn)
99 #else
100 	double scalb(double x, double fn)
101 #endif
102 #else
103 	double scalb(x, fn)
104 #ifdef _SCALB_INT
105 	double x; int fn;
106 #else
107 	double x,fn;
108 #endif
109 #endif
110 {
111 #ifdef _SCALB_INT
112 	return (double) scalbf((float) x, fn);
113 #else
114 	return (double) scalbf((float) x, (float) fn);
115 #endif
116 }
117 
118 #endif /* defined(_DOUBLE_IS_32BITS) */
119