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 #include "math.h"
17 #include "math_private.h"
18
19 static const float
20 one = 1.0000000000e+00, /* 0x3F800000 */
21 ln2 = 6.9314718246e-01, /* 0x3f317218 */
22 huge= 1.0000000000e+30;
23
24 float
asinhf(float x)25 asinhf(float x)
26 {
27 float t,w;
28 int32_t hx,ix;
29 GET_FLOAT_WORD(hx,x);
30 ix = hx&0x7fffffff;
31 if(ix>=0x7f800000) return x+x; /* x is inf or NaN */
32 if(ix< 0x31800000) { /* |x|<2**-28 */
33 if(huge+x>one) return x; /* return x inexact except 0 */
34 }
35 if(ix>0x4d800000) { /* |x| > 2**28 */
36 w = logf(fabsf(x))+ln2;
37 } else if (ix>0x40000000) { /* 2**28 > |x| > 2.0 */
38 t = fabsf(x);
39 w = logf((float)2.0*t+one/(sqrtf(x*x+one)+t));
40 } else { /* 2.0 > |x| > 2**-28 */
41 t = x*x;
42 w =log1pf(fabsf(x)+t/(one+sqrtf(one+t)));
43 }
44 if(hx>0) return w; else return -w;
45 }
46