xref: /dflybsd-src/contrib/openbsd_libm/src/s_asinhf.c (revision 4382f29d99a100bd77a81697c2f699c11f6a472a)
1*05a0b428SJohn Marino /* s_asinhf.c -- float version of s_asinh.c.
2*05a0b428SJohn Marino  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3*05a0b428SJohn Marino  */
4*05a0b428SJohn Marino 
5*05a0b428SJohn Marino /*
6*05a0b428SJohn Marino  * ====================================================
7*05a0b428SJohn Marino  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8*05a0b428SJohn Marino  *
9*05a0b428SJohn Marino  * Developed at SunPro, a Sun Microsystems, Inc. business.
10*05a0b428SJohn Marino  * Permission to use, copy, modify, and distribute this
11*05a0b428SJohn Marino  * software is freely granted, provided that this notice
12*05a0b428SJohn Marino  * is preserved.
13*05a0b428SJohn Marino  * ====================================================
14*05a0b428SJohn Marino  */
15*05a0b428SJohn Marino 
16*05a0b428SJohn Marino #include "math.h"
17*05a0b428SJohn Marino #include "math_private.h"
18*05a0b428SJohn Marino 
19*05a0b428SJohn Marino static const float
20*05a0b428SJohn Marino one =  1.0000000000e+00, /* 0x3F800000 */
21*05a0b428SJohn Marino ln2 =  6.9314718246e-01, /* 0x3f317218 */
22*05a0b428SJohn Marino huge=  1.0000000000e+30;
23*05a0b428SJohn Marino 
24*05a0b428SJohn Marino float
asinhf(float x)25*05a0b428SJohn Marino asinhf(float x)
26*05a0b428SJohn Marino {
27*05a0b428SJohn Marino 	float t,w;
28*05a0b428SJohn Marino 	int32_t hx,ix;
29*05a0b428SJohn Marino 	GET_FLOAT_WORD(hx,x);
30*05a0b428SJohn Marino 	ix = hx&0x7fffffff;
31*05a0b428SJohn Marino 	if(ix>=0x7f800000) return x+x;	/* x is inf or NaN */
32*05a0b428SJohn Marino 	if(ix< 0x31800000) {	/* |x|<2**-28 */
33*05a0b428SJohn Marino 	    if(huge+x>one) return x;	/* return x inexact except 0 */
34*05a0b428SJohn Marino 	}
35*05a0b428SJohn Marino 	if(ix>0x4d800000) {	/* |x| > 2**28 */
36*05a0b428SJohn Marino 	    w = logf(fabsf(x))+ln2;
37*05a0b428SJohn Marino 	} else if (ix>0x40000000) {	/* 2**28 > |x| > 2.0 */
38*05a0b428SJohn Marino 	    t = fabsf(x);
39*05a0b428SJohn Marino 	    w = logf((float)2.0*t+one/(sqrtf(x*x+one)+t));
40*05a0b428SJohn Marino 	} else {		/* 2.0 > |x| > 2**-28 */
41*05a0b428SJohn Marino 	    t = x*x;
42*05a0b428SJohn Marino 	    w =log1pf(fabsf(x)+t/(one+sqrtf(one+t)));
43*05a0b428SJohn Marino 	}
44*05a0b428SJohn Marino 	if(hx>0) return w; else return -w;
45*05a0b428SJohn Marino }
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