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11210 libm should be cstyle(1ONBLD) clean
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--- old/usr/src/lib/libm/common/complex/k_cexp.c
+++ new/usr/src/lib/libm/common/complex/k_cexp.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 -/* INDENT OFF */
31 +
31 32 /*
32 33 * double __k_cexp(double x, int *n);
33 34 * Returns the exponential of x in the form of 2**n * y, y=__k_cexp(x,&n).
34 35 *
35 36 * Method
36 37 * 1. Argument reduction:
37 38 * Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658.
38 39 * Given x, find r and integer k such that
39 40 *
40 41 * x = k*ln2 + r, |r| <= 0.5*ln2.
41 42 *
42 43 * Here r will be represented as r = hi-lo for better
43 44 * accuracy.
44 45 *
45 46 * 2. Approximation of exp(r) by a special rational function on
46 47 * the interval [0,0.34658]:
47 48 * Write
48 49 * R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ...
49 50 * We use a special Remez algorithm on [0,0.34658] to generate
50 - * a polynomial of degree 5 to approximate R. The maximum error
51 + * a polynomial of degree 5 to approximate R. The maximum error
51 52 * of this polynomial approximation is bounded by 2**-59. In
52 53 * other words,
53 54 * R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5
54 - * (where z=r*r, and the values of P1 to P5 are listed below)
55 + * (where z=r*r, and the values of P1 to P5 are listed below)
55 56 * and
56 57 * | 5 | -59
57 58 * | 2.0+P1*z+...+P5*z - R(z) | <= 2
58 59 * | |
59 60 * The computation of exp(r) thus becomes
60 61 * 2*r
61 62 * exp(r) = 1 + -------
62 63 * R - r
63 64 * r*R1(r)
64 65 * = 1 + r + ----------- (for better accuracy)
65 66 * 2 - R1(r)
66 67 * where
67 68 * 2 4 10
68 69 * R1(r) = r - (P1*r + P2*r + ... + P5*r ).
69 70 *
70 71 * 3. Return n = k and __k_cexp = exp(r).
71 72 *
72 73 * Special cases:
73 74 * exp(INF) is INF, exp(NaN) is NaN;
74 75 * exp(-INF) is 0, and
75 76 * for finite argument, only exp(0)=1 is exact.
76 77 *
77 78 * Range and Accuracy:
78 79 * When |x| is really big, say |x| > 50000, the accuracy
79 80 * is not important because the ultimate result will over or under
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80 81 * flow. So we will simply replace n = 50000 and r = 0.0. For
81 82 * moderate size x, according to an error analysis, the error is
82 83 * always less than 1 ulp (unit in the last place).
83 84 *
84 85 * Constants:
85 86 * The hexadecimal values are the intended ones for the following
86 87 * constants. The decimal values may be used, provided that the
87 88 * compiler will convert from decimal to binary accurately enough
88 89 * to produce the hexadecimal values shown.
89 90 */
90 -/* INDENT ON */
91 91
92 -#include "libm.h" /* __k_cexp */
93 -#include "complex_wrapper.h" /* HI_WORD/LO_WORD */
92 +#include "libm.h" /* __k_cexp */
93 +#include "complex_wrapper.h" /* HI_WORD/LO_WORD */
94 94
95 -/* INDENT OFF */
96 -static const double
97 -one = 1.0,
98 -two128 = 3.40282366920938463463e+38,
99 -halF[2] = {
100 - 0.5, -0.5,
101 -},
102 -ln2HI[2] = {
95 +static const double one = 1.0,
96 + two128 = 3.40282366920938463463e+38;
97 +
98 +static const double halF[2] = { 0.5, -0.5, };
99 +
100 +static const double ln2HI[2] = {
103 101 6.93147180369123816490e-01, /* 0x3fe62e42, 0xfee00000 */
104 102 -6.93147180369123816490e-01, /* 0xbfe62e42, 0xfee00000 */
105 -},
106 -ln2LO[2] = {
103 +};
104 +
105 +static const double ln2LO[2] = {
107 106 1.90821492927058770002e-10, /* 0x3dea39ef, 0x35793c76 */
108 107 -1.90821492927058770002e-10, /* 0xbdea39ef, 0x35793c76 */
109 -},
110 -invln2 = 1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */
111 -P1 = 1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */
112 -P2 = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */
113 -P3 = 6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */
114 -P4 = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */
115 -P5 = 4.13813679705723846039e-08; /* 0x3E663769, 0x72BEA4D0 */
116 -/* INDENT ON */
108 +};
109 +
110 +static const double
111 + invln2 = 1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */
112 + P1 = 1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */
113 + P2 = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */
114 + P3 = 6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */
115 + P4 = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */
116 + P5 = 4.13813679705723846039e-08; /* 0x3E663769, 0x72BEA4D0 */
117 +
117 118
118 119 double
119 -__k_cexp(double x, int *n) {
120 +__k_cexp(double x, int *n)
121 +{
120 122 double hi = 0.0L, lo = 0.0L, c, t;
121 123 int k, xsb;
122 124 unsigned hx, lx;
123 125
124 - hx = HI_WORD(x); /* high word of x */
125 - lx = LO_WORD(x); /* low word of x */
126 - xsb = (hx >> 31) & 1; /* sign bit of x */
127 - hx &= 0x7fffffff; /* high word of |x| */
126 + hx = HI_WORD(x); /* high word of x */
127 + lx = LO_WORD(x); /* low word of x */
128 + xsb = (hx >> 31) & 1; /* sign bit of x */
129 + hx &= 0x7fffffff; /* high word of |x| */
128 130
129 131 /* filter out non-finite argument */
130 - if (hx >= 0x40e86a00) { /* if |x| > 50000 */
132 + if (hx >= 0x40e86a00) { /* if |x| > 50000 */
131 133 if (hx >= 0x7ff00000) {
132 134 *n = 1;
135 +
133 136 if (((hx & 0xfffff) | lx) != 0)
134 - return (x + x); /* NaN */
137 + return (x + x); /* NaN */
135 138 else
136 139 return ((xsb == 0) ? x : 0.0);
137 - /* exp(+-inf)={inf,0} */
140 +
141 + /* exp(+-inf)={inf,0} */
138 142 }
143 +
139 144 *n = (xsb == 0) ? 50000 : -50000;
140 145 return (one + ln2LO[1] * ln2LO[1]); /* generate inexact */
141 146 }
142 147
143 148 *n = 0;
149 +
144 150 /* argument reduction */
145 - if (hx > 0x3fd62e42) { /* if |x| > 0.5 ln2 */
151 + if (hx > 0x3fd62e42) { /* if |x| > 0.5 ln2 */
146 152 if (hx < 0x3FF0A2B2) { /* and |x| < 1.5 ln2 */
147 153 hi = x - ln2HI[xsb];
148 154 lo = ln2LO[xsb];
149 155 k = 1 - xsb - xsb;
150 156 } else {
151 - k = (int) (invln2 * x + halF[xsb]);
157 + k = (int)(invln2 * x + halF[xsb]);
152 158 t = k;
153 159 hi = x - t * ln2HI[0];
154 - /* t*ln2HI is exact for t<2**20 */
160 + /* t*ln2HI is exact for t<2**20 */
155 161 lo = t * ln2LO[0];
156 162 }
163 +
157 164 x = hi - lo;
158 165 *n = k;
159 166 } else if (hx < 0x3e300000) { /* when |x|<2**-28 */
160 167 return (one + x);
161 - } else
168 + } else {
162 169 k = 0;
170 + }
163 171
164 172 /* x is now in primary range */
165 173 t = x * x;
166 174 c = x - t * (P1 + t * (P2 + t * (P3 + t * (P4 + t * P5))));
167 - if (k == 0)
175 +
176 + if (k == 0) {
168 177 return (one - ((x * c) / (c - 2.0) - x));
169 - else {
178 + } else {
170 179 t = one - ((lo - (x * c) / (2.0 - c)) - hi);
180 +
171 181 if (k > 128) {
172 182 t *= two128;
173 183 *n = k - 128;
174 184 } else if (k > 0) {
175 185 HI_WORD(t) += (k << 20);
176 186 *n = 0;
177 187 }
188 +
178 189 return (t);
179 190 }
180 191 }
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