xref: /freebsd/lib/msun/src/e_scalbf.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /* e_scalbf.c -- float version of e_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 #include <sys/cdefs.h>
17 __FBSDID("$FreeBSD$");
18 
19 #include "math.h"
20 #include "math_private.h"
21 
22 #ifdef _SCALB_INT
23 float
24 __ieee754_scalbf(float x, int fn)
25 #else
26 float
27 __ieee754_scalbf(float x, float fn)
28 #endif
29 {
30 #ifdef _SCALB_INT
31 	return scalbnf(x,fn);
32 #else
33 	if ((isnanf)(x)||(isnanf)(fn)) return x*fn;
34 	if (!finitef(fn)) {
35 	    if(fn>(float)0.0) return x*fn;
36 	    else       return x/(-fn);
37 	}
38 	if (rintf(fn)!=fn) return (fn-fn)/(fn-fn);
39 	if ( fn > (float)65000.0) return scalbnf(x, 65000);
40 	if (-fn > (float)65000.0) return scalbnf(x,-65000);
41 	return scalbnf(x,(int)fn);
42 #endif
43 }
44