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.
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.
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]
22 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
25 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
26 * Use is subject to license terms.
29 #pragma weak __cosh = cosh
34 * Code originated from 4.3bsd.
35 * Modified by K.C. Ng for SUN 4.0 libm.
37 * 1. Replace x by |x| (cosh(x) = cosh(-x)).
40 * 0 <= x <= 0.3465 : cosh(x) := 1 + -------------------
44 * 0.3465 <= x <= 22 : cosh(x) := -------------------
46 * 22 <= x <= lnovft : cosh(x) := exp(x)/2
47 * lnovft <= x < INF : cosh(x) := scalbn(exp(x-1024*ln2),1023)
49 * Note: .3465 is a number near one half of ln2.
52 * cosh(x) is |x| if x is +INF, -INF, or NaN.
53 * only cosh(0)=1 is exact for finite x.
60 ln2
= 6.93147180559945286227e-01,
61 ln2hi
= 6.93147180369123816490e-01,
62 ln2lo
= 1.90821492927058770002e-10,
63 lnovft
= 7.09782712893383973096e+02;
76 w
= 1.0 + (t
* t
) / (w
+ w
);
78 } else if (w
< 22.0) {
80 return (0.5 * (t
+ 1.0 / t
));
81 } else if (w
<= lnovft
) {
82 return (0.5 * exp(w
));
84 w
= (w
- 1024 * ln2hi
) - 1024 * ln2lo
;
86 return (_SVID_libm_err(x
, x
, 5));
88 return (scalbn(exp(w
), 1023));