xref: /illumos-gate/usr/src/lib/libm/common/complex/ccoshl.c (revision 1ed6b69a5ca1ca3ee5e9a4931f74e2237c7e1c9f)
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 ccoshl = __ccoshl
31 
32 #include "libm.h"	/* coshl/expl/fabsl/scalbnl/sincosl/sinhl/__k_cexpl */
33 #include "complex_wrapper.h"
34 
35 /* INDENT OFF */
36 static const long double zero = 0.0L, half = 0.5L;
37 /* INDENT ON */
38 
39 ldcomplex
40 ccoshl(ldcomplex z) {
41 	long double t, x, y, S, C;
42 	int hx, ix, hy, iy, n;
43 	ldcomplex ans;
44 
45 	x = LD_RE(z);
46 	y = LD_IM(z);
47 	hx = HI_XWORD(x);
48 	ix = hx & 0x7fffffff;
49 	hy = HI_XWORD(y);
50 	iy = hy & 0x7fffffff;
51 	x = fabsl(x);
52 	y = fabsl(y);
53 
54 	(void) sincosl(y, &S, &C);
55 	if (ix >= 0x4004e000) {	/* |x| > 60 = prec/2 (14,28,34,60) */
56 		if (ix >= 0x400C62E4) {	/* |x| > 11356.52... ~ log(2**16384) */
57 			if (ix >= 0x7fff0000) {	/* |x| is inf or NaN */
58 				if (y == zero) {
59 					LD_RE(ans) = x;
60 					LD_IM(ans) = y;
61 				} else if (iy >= 0x7fff0000) {
62 					LD_RE(ans) = x;
63 					LD_IM(ans) = x - y;
64 				} else {
65 					LD_RE(ans) = C * x;
66 					LD_IM(ans) = S * x;
67 				}
68 			} else {
69 				t = __k_cexpl(x, &n);
70 						/* return exp(x)=t*2**n */
71 				LD_RE(ans) = scalbnl(C * t, n - 1);
72 				LD_IM(ans) = scalbnl(S * t, n - 1);
73 			}
74 		} else {
75 			t = expl(x) * half;
76 			LD_RE(ans) = C * t;
77 			LD_IM(ans) = S * t;
78 		}
79 	} else {
80 		if (x == zero) {	/* x = 0, return (C,0) */
81 			LD_RE(ans) = C;
82 			LD_IM(ans) = zero;
83 		} else {
84 			LD_RE(ans) = C * coshl(x);
85 			LD_IM(ans) = S * sinhl(x);
86 		}
87 	}
88 	if ((hx ^ hy) < 0)
89 		LD_IM(ans) = -LD_IM(ans);
90 	return (ans);
91 }
92