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11210 libm should be cstyle(1ONBLD) clean
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--- old/usr/src/lib/libm/common/Q/tanhl.c
+++ new/usr/src/lib/libm/common/Q/tanhl.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.
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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 27 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
27 28 * Use is subject to license terms.
28 29 */
29 30
30 31 #pragma weak __tanhl = tanhl
31 32
32 33 /*
33 34 * tanhl(x) returns the hyperbolic tangent of x
34 35 *
35 36 * Method :
36 37 * 1. reduce x to non-negative: tanhl(-x) = - tanhl(x).
37 38 * 2.
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38 39 * 0 < x <= small : tanhl(x) := x
39 40 * -expm1l(-2x)
40 41 * small < x <= 1 : tanhl(x) := --------------
41 42 * expm1l(-2x) + 2
42 43 * 2
43 44 * 1 <= x <= threshold : tanhl(x) := 1 - ---------------
44 45 * expm1l(2x) + 2
45 46 * threshold < x <= INF : tanhl(x) := 1.
46 47 *
47 48 * where
48 - * single : small = 1.e-5 threshold = 11.0
49 - * double : small = 1.e-10 threshold = 22.0
50 - * quad : small = 1.e-20 threshold = 45.0
49 + * single : small = 1.e-5 threshold = 11.0
50 + * double : small = 1.e-10 threshold = 22.0
51 + * quad : small = 1.e-20 threshold = 45.0
51 52 *
52 53 * Note: threshold was chosen so that
53 54 * fl(1.0+2/(expm1(2*threshold)+2)) == 1.
54 55 *
55 56 * Special cases:
56 57 * tanhl(NaN) is NaN;
57 58 * only tanhl(0.0)=0.0 is exact for finite argument.
58 59 */
59 60
60 61 #include "libm.h"
61 62 #include "longdouble.h"
62 63
63 -static const long double small = 1.0e-20L, one = 1.0, two = 2.0,
64 +static const long double small = 1.0e-20L,
65 + one = 1.0,
66 + two = 2.0,
64 67 #ifndef lint
65 68 big = 1.0e+20L,
66 69 #endif
67 70 threshold = 45.0L;
68 71
69 72 long double
70 -tanhl(long double x) {
73 +tanhl(long double x)
74 +{
71 75 long double t, y, z;
72 76 int signx;
77 +
73 78 #ifndef lint
74 79 volatile long double dummy;
75 80 #endif
76 81
77 82 if (isnanl(x))
78 83 return (x + x); /* x is NaN */
84 +
79 85 signx = signbitl(x);
80 86 t = fabsl(x);
81 87 z = one;
88 +
82 89 if (t <= threshold) {
83 - if (t > one)
90 + if (t > one) {
84 91 z = one - two / (expm1l(t + t) + two);
85 - else if (t > small) {
92 + } else if (t > small) {
86 93 y = expm1l(-t - t);
87 94 z = -y / (y + two);
88 95 } else {
89 96 #ifndef lint
90 97 dummy = t + big;
91 - /* inexact if t != 0 */
98 + /* inexact if t != 0 */
92 99 #endif
93 100 return (x);
94 101 }
95 - } else if (!finitel(t))
102 + } else if (!finitel(t)) {
96 103 return (copysignl(one, x));
97 - else
104 + } else {
98 105 return (signx ? -z + small * small : z - small * small);
106 + }
107 +
99 108 return (signx ? -z : z);
100 109 }
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