1/* s_asinhf.c -- float version of s_asinh.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#ifndef lint
17static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_asinhf.c,v 1.8 2002/05/28 18:15:04 alfred Exp $";
18#endif
19
20#include "math.h"
21#include "math_private.h"
22
23static const float
24one =  1.0000000000e+00, /* 0x3F800000 */
25ln2 =  6.9314718246e-01, /* 0x3f317218 */
26huge=  1.0000000000e+30;
27
28float
29asinhf(float x)
30{
31	float t,w;
32	int32_t hx,ix;
33	GET_FLOAT_WORD(hx,x);
34	ix = hx&0x7fffffff;
35	if(ix>=0x7f800000) return x+x;	/* x is inf or NaN */
36	if(ix< 0x31800000) {	/* |x|<2**-28 */
37	    if(huge+x>one) return x;	/* return x inexact except 0 */
38	}
39	if(ix>0x4d800000) {	/* |x| > 2**28 */
40	    w = __ieee754_logf(fabsf(x))+ln2;
41	} else if (ix>0x40000000) {	/* 2**28 > |x| > 2.0 */
42	    t = fabsf(x);
43	    w = __ieee754_logf((float)2.0*t+one/(__ieee754_sqrtf(x*x+one)+t));
44	} else {		/* 2.0 > |x| > 2**-28 */
45	    t = x*x;
46	    w =log1pf(fabsf(x)+t/(one+__ieee754_sqrtf(one+t)));
47	}
48	if(hx>0) return w; else return -w;
49}
50