xref: /titanic_41/usr/src/lib/libm/common/R/atanhf.c (revision a9d3dcd5820128b4f34bf38f447e47aa95c004e8)
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  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
23  */
24 /*
25  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
26  * Use is subject to license terms.
27  */
28 
29 #pragma weak __atanhf = atanhf
30 
31 #include "libm.h"
32 
33 static const float zero = 0.0f;
34 
35 float
atanhf(float x)36 atanhf(float x) {
37 	int	ix;
38 
39 	ix = *((int *)&x) & ~0x80000000;
40 	if (ix > 0x3f800000)	/* |x| > 1 or x is nan */
41 		return ((x * zero) / zero);
42 	if (ix == 0x3f800000)	/* |x| == 1 */
43 		return (x / zero);
44 	return ((float)atanh((double)x));
45 }
46