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11210 libm should be cstyle(1ONBLD) clean
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--- old/usr/src/lib/libm/common/Q/expl.c
+++ new/usr/src/lib/libm/common/Q/expl.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 /*
31 32 * expl(x)
32 33 * Table driven method
33 34 * Written by K.C. Ng, November 1988.
34 35 * Algorithm :
35 36 * 1. Argument Reduction: given the input x, find r and integer k
36 37 * and j such that
37 38 * x = (32k+j)*ln2 + r, |r| <= (1/64)*ln2 .
38 39 *
39 40 * 2. expl(x) = 2^k * (2^(j/32) + 2^(j/32)*expm1(r))
40 41 * Note:
41 42 * a. expm1(r) = (2r)/(2-R), R = r - r^2*(t1 + t2*r^2)
42 43 * b. 2^(j/32) is represented as
43 44 * _TBL_expl_hi[j]+_TBL_expl_lo[j]
44 45 * where
45 46 * _TBL_expl_hi[j] = 2^(j/32) rounded
46 47 * _TBL_expl_lo[j] = 2^(j/32) - _TBL_expl_hi[j].
47 48 *
48 49 * Special cases:
49 50 * expl(INF) is INF, expl(NaN) is NaN;
50 51 * expl(-INF)= 0;
51 52 * for finite argument, only expl(0)=1 is exact.
52 53 *
53 54 * Accuracy:
54 55 * according to an error analysis, the error is always less than
55 56 * an ulp (unit in the last place).
56 57 *
57 58 * Misc. info.
58 59 * For 113 bit long double
59 60 * if x > 1.135652340629414394949193107797076342845e+4
60 61 * then expl(x) overflow;
61 62 * if x < -1.143346274333629787883724384345262150341e+4
62 63 * then expl(x) underflow
63 64 *
64 65 * Constants:
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65 66 * Only decimal values are given. We assume that the compiler will convert
66 67 * from decimal to binary accurately enough to produce the correct
67 68 * hexadecimal values.
68 69 */
69 70
70 71 #pragma weak __expl = expl
71 72
72 73 #include "libm.h"
73 74
74 75 extern const long double _TBL_expl_hi[], _TBL_expl_lo[];
75 -
76 -static const long double
77 -one = 1.0L,
78 -two = 2.0L,
79 -ln2_64 = 1.083042469624914545964425189778400898568e-2L,
80 -ovflthreshold = 1.135652340629414394949193107797076342845e+4L,
81 -unflthreshold = -1.143346274333629787883724384345262150341e+4L,
82 -invln2_32 = 4.616624130844682903551758979206054839765e+1L,
83 -ln2_32hi = 2.166084939249829091928849858592451515688e-2L,
84 -ln2_32lo = 5.209643502595475652782654157501186731779e-27L;
76 +static const long double one = 1.0L,
77 + two = 2.0L,
78 + ln2_64 = 1.083042469624914545964425189778400898568e-2L,
79 + ovflthreshold = 1.135652340629414394949193107797076342845e+4L,
80 + unflthreshold = -1.143346274333629787883724384345262150341e+4L,
81 + invln2_32 = 4.616624130844682903551758979206054839765e+1L,
82 + ln2_32hi = 2.166084939249829091928849858592451515688e-2L,
83 + ln2_32lo = 5.209643502595475652782654157501186731779e-27L;
85 84
86 85 /* rational approximation coeffs for [-(ln2)/64,(ln2)/64] */
87 -static const long double
88 -t1 = 1.666666666666666666666666666660876387437e-1L,
89 -t2 = -2.777777777777777777777707812093173478756e-3L,
90 -t3 = 6.613756613756613482074280932874221202424e-5L,
91 -t4 = -1.653439153392139954169609822742235851120e-6L,
92 -t5 = 4.175314851769539751387852116610973796053e-8L;
86 +static const long double t1 = 1.666666666666666666666666666660876387437e-1L,
87 + t2 = -2.777777777777777777777707812093173478756e-3L,
88 + t3 = 6.613756613756613482074280932874221202424e-5L,
89 + t4 = -1.653439153392139954169609822742235851120e-6L,
90 + t5 = 4.175314851769539751387852116610973796053e-8L;
93 91
94 92 long double
95 -expl(long double x) {
96 - int *px = (int *) &x, ix, j, k, m;
93 +expl(long double x)
94 +{
95 + int *px = (int *)&x, ix, j, k, m;
97 96 long double t, r;
98 97
99 - ix = px[0]; /* high word of x */
98 + ix = px[0]; /* high word of x */
99 +
100 100 if (ix >= 0x7fff0000)
101 - return (x + x); /* NaN of +inf */
102 - if (((unsigned) ix) >= 0xffff0000)
103 - return (-one / x); /* NaN or -inf */
101 + return (x + x); /* NaN of +inf */
102 +
103 + if (((unsigned)ix) >= 0xffff0000)
104 + return (-one / x); /* NaN or -inf */
105 +
104 106 if ((ix & 0x7fffffff) < 0x3fc30000) {
105 - if ((int) x < 1)
107 + if ((int)x < 1)
106 108 return (one + x); /* |x|<2^-60 */
107 109 }
110 +
108 111 if (ix > 0) {
109 112 if (x > ovflthreshold)
110 113 return (scalbnl(x, 20000));
111 - k = (int) (invln2_32 * (x + ln2_64));
114 +
115 + k = (int)(invln2_32 * (x + ln2_64));
112 116 } else {
113 117 if (x < unflthreshold)
114 118 return (scalbnl(-x, -40000));
115 - k = (int) (invln2_32 * (x - ln2_64));
119 +
120 + k = (int)(invln2_32 * (x - ln2_64));
116 121 }
117 - j = k&0x1f;
118 - m = k>>5;
119 - t = (long double) k;
120 - x = (x - t * ln2_32hi) - t * ln2_32lo;
121 - t = x * x;
122 - r = (x - t * (t1 + t * (t2 + t * (t3 + t * (t4 + t * t5))))) - two;
123 - x = _TBL_expl_hi[j] - ((_TBL_expl_hi[j] * (x + x)) / r -
124 - _TBL_expl_lo[j]);
122 +
123 + j = k & 0x1f;
124 + m = k >> 5;
125 + t = (long double)k;
126 + x = (x - t * ln2_32hi) - t * ln2_32lo;
127 + t = x * x;
128 + r = (x - t * (t1 + t * (t2 + t * (t3 + t * (t4 + t * t5))))) - two;
129 + x = _TBL_expl_hi[j] - ((_TBL_expl_hi[j] * (x + x)) / r -
130 + _TBL_expl_lo[j]);
125 131 return (scalbnl(x, m));
126 132 }
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