Print this page
Split |
Close |
Expand all |
Collapse all |
--- old/usr/src/lib/libm/common/LD/tanl.c
+++ new/usr/src/lib/libm/common/LD/tanl.c
1 1 /*
2 2 * CDDL HEADER START
3 3 *
4 4 * The contents of this file are subject to the terms of the
5 5 * Common Development and Distribution License (the "License").
6 6 * You may not use this file except in compliance with the License.
7 7 *
8 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 9 * or http://www.opensolaris.org/os/licensing.
10 10 * See the License for the specific language governing permissions
11 11 * and limitations under the License.
12 12 *
13 13 * When distributing Covered Code, include this CDDL HEADER in each
14 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 15 * If applicable, add the following below this CDDL HEADER, with the
16 16 * fields enclosed by brackets "[]" replaced with your own identifying
17 17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 18 *
19 19 * CDDL HEADER END
20 20 */
21 21
22 22 /*
23 23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
24 24 */
25 25 /*
26 26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
27 27 * Use is subject to license terms.
28 28 */
29 29
30 30 #pragma weak tanl = __tanl
31 31
32 32 /* INDENT OFF */
33 33 /* cosl(x)
34 34 * Table look-up algorithm by K.C. Ng, November, 1989.
35 35 *
36 36 * kernel function:
37 37 * __k_tanl ... tangent function on [-pi/4,pi/4]
38 38 * __rem_pio2l ... argument reduction routine
39 39 *
40 40 * Method.
41 41 * Let S and C denote the sin and cos respectively on [-PI/4, +PI/4].
42 42 * 1. Assume the argument x is reduced to y1+y2 = x-k*pi/2 in
43 43 * [-pi/2 , +pi/2], and let n = k mod 4.
44 44 * 2. Let S=S(y1+y2), C=C(y1+y2). Depending on n, we have
45 45 *
46 46 * n sin(x) cos(x) tan(x)
47 47 * ----------------------------------------------------------
48 48 * 0 S C S/C
49 49 * 1 C -S -C/S
50 50 * 2 -S -C S/C
51 51 * 3 -C S -C/S
52 52 * ----------------------------------------------------------
53 53 *
54 54 * Special cases:
55 55 * Let trig be any of sin, cos, or tan.
56 56 * trig(+-INF) is NaN, with signals;
57 57 * trig(NaN) is that NaN;
58 58 *
59 59 * Accuracy:
60 60 * computer TRIG(x) returns trig(x) nearly rounded.
61 61 */
62 62 /* INDENT ON */
63 63
↓ open down ↓ |
63 lines elided |
↑ open up ↑ |
64 64 #include "libm.h"
65 65 #include "libm_synonyms.h"
66 66 #include "longdouble.h"
67 67
68 68 #include <sys/isa_defs.h>
69 69
70 70 long double
71 71 tanl(long double x) {
72 72 long double y[2], z = 0.0L;
73 73 int n, ix;
74 -#if defined(_LITTLE_ENDIAN)
74 +#if defined(__i386) || defined(__amd64)
75 75 int *px = (int *) &x;
76 76 #endif
77 77
78 78 /* trig(Inf or NaN) is NaN */
79 79 if (!finitel(x))
80 80 return x - x;
81 81
82 82 /* High word of x. */
83 -#if defined(_BIG_ENDIAN)
84 - ix = *(int *) &x;
85 -#else
83 +#if defined(__i386) || defined(__amd64)
86 84 XTOI(px, ix);
85 +#else
86 + ix = *(int *) &x;
87 87 #endif
88 88
89 89 /* |x| ~< pi/4 */
90 90 ix &= 0x7fffffff;
91 91 if (ix <= 0x3ffe9220)
92 92 return __k_tanl(x, z, 0);
93 93
94 94 /* argument reduction needed */
95 95 else {
96 96 n = __rem_pio2l(x, y);
97 97 return __k_tanl(y[0], y[1], n & 1);
98 98 }
99 99 }
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX