1 /* w_log10f.c -- float version of w_log10.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 #if defined(LIBM_SCCS) && !defined(lint)
18 __RCSID("$NetBSD: w_log2f.c,v 1.1 2005/07/21 16:58:39 christos Exp $");
19 #endif
20
21 /*
22 * wrapper log2f(X)
23 */
24
25 #include "math.h"
26 #include "math_private.h"
27
28
29 float
log2f(float x)30 log2f(float x) /* wrapper log2f */
31 {
32 #ifdef _IEEE_LIBM
33 return __ieee754_log2f(x);
34 #else
35 float z;
36 z = __ieee754_log2f(x);
37 if(_LIB_VERSION == _IEEE_ || isnanf(x)) return z;
38 if(x<=(float)0.0) {
39 if(x==(float)0.0)
40 /* log2(0) */
41 return (float)__kernel_standard((double)x,(double)x,148);
42 else
43 /* log2(x<0) */
44 return (float)__kernel_standard((double)x,(double)x,149);
45 } else
46 return z;
47 #endif
48 }
49