1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24 */
25/*
26 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
27 * Use is subject to license terms.
28 */
29
30#pragma weak __asinhl = asinhl
31
32#include "libm.h"
33
34static const long double
35	ln2	= 6.931471805599453094172321214581765680755e-0001L,
36	one	= 1.0L,
37	big	= 1.0e+20L,
38	tiny	= 1.0e-20L;
39
40long double
41asinhl(long double x) {
42	long double t, w;
43#ifndef lint
44	volatile long double dummy __unused;
45#endif
46
47	w = fabsl(x);
48	if (isnanl(x))
49		return (x + x);	/* x is NaN */
50	if (w < tiny) {
51#ifndef lint
52		dummy = x + big;	/* inexact if x != 0 */
53#endif
54		return (x);	/* tiny x */
55	} else if (w < big) {
56		t = one / w;
57		return (copysignl(log1pl(w + w / (t + sqrtl(one + t * t))), x));
58	} else
59		return (copysignl(logl(w) + ln2, x));
60}
61