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11210 libm should be cstyle(1ONBLD) clean
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--- old/usr/src/lib/libm/common/C/tanh.c
+++ new/usr/src/lib/libm/common/C/tanh.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 __tanh = tanh
31 32
32 -/* INDENT OFF */
33 +
33 34 /*
34 35 * TANH(X)
35 36 * RETURN THE HYPERBOLIC TANGENT OF X
36 37 * code based on 4.3bsd
37 38 * Modified by K.C. Ng for sun 4.0, Jan 31, 1987
38 39 *
39 40 * Method :
40 41 * 1. reduce x to non-negative by tanh(-x) = - tanh(x).
41 42 * 2.
42 43 * 0 < x <= 1.e-10 : tanh(x) := x
43 44 * -expm1(-2x)
44 45 * 1.e-10 < x <= 1 : tanh(x) := --------------
45 46 * expm1(-2x) + 2
46 47 * 2
47 48 * 1 <= x <= 22.0 : tanh(x) := 1 - ---------------
48 49 * expm1(2x) + 2
49 50 * 22.0 < x <= INF : tanh(x) := 1.
50 51 *
51 52 * Note: 22 was chosen so that fl(1.0+2/(expm1(2*22)+2)) == 1.
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52 53 *
53 54 * Special cases:
54 55 * tanh(NaN) is NaN;
55 56 * only tanh(0)=0 is exact for finite argument.
56 57 */
57 58
58 59 #include "libm.h"
59 60 #include "libm_protos.h"
60 61 #include <math.h>
61 62
62 -static const double
63 - one = 1.0,
64 - two = 2.0,
65 - small = 1.0e-10,
66 - big = 1.0e10;
67 -/* INDENT ON */
63 +static const double one = 1.0, two = 2.0, small = 1.0e-10, big = 1.0e10;
64 +
68 65
69 66 double
70 67 tanh(double x)
71 68 {
72 69 double t, y, z;
73 70 int signx;
74 71 volatile double dummy __unused;
75 72
76 73 if (isnan(x))
77 - return (x * x); /* + -> * for Cheetah */
74 + return (x * x); /* + -> * for Cheetah */
75 +
78 76 signx = signbit(x);
79 77 t = fabs(x);
80 78 z = one;
79 +
81 80 if (t <= 22.0) {
82 - if (t > one)
81 + if (t > one) {
83 82 z = one - two / (expm1(t + t) + two);
84 - else if (t > small) {
83 + } else if (t > small) {
85 84 y = expm1(-t - t);
86 85 z = -y / (y + two);
87 86 } else {
88 87 /* raise the INEXACT flag for non-zero t */
89 88 dummy = t + big;
90 89 #ifdef lint
91 90 dummy = dummy;
92 91 #endif
93 92 return (x);
94 93 }
95 - } else if (!finite(t))
94 + } else if (!finite(t)) {
96 95 return (copysign(1.0, x));
97 - else
96 + } else {
98 97 return ((signx != 0) ? -z + small * small : z - small * small);
98 + }
99 99
100 100 return ((signx != 0) ? -z : z);
101 101 }
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