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11210 libm should be cstyle(1ONBLD) clean
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--- old/usr/src/lib/libm/common/C/hypot.c
+++ new/usr/src/lib/libm/common/C/hypot.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 __hypot = hypot
31 32
32 -/* INDENT OFF */
33 +
33 34 /*
34 35 * Hypot(x, y)
35 36 * by K.C. Ng for SUN 4.0 libm, updated 3/11/2003.
36 37 * Method :
37 38 * A. When rounding is rounded-to-nearest:
38 39 * If z = x * x + y * y has error less than sqrt(2) / 2 ulp than
39 40 * sqrt(z) has error less than 1 ulp.
40 41 * So, compute sqrt(x*x+y*y) with some care as follows:
41 42 * Assume x > y > 0;
42 43 * 1. Check whether save and set rounding to round-to-nearest
43 44 * 2. if x > 2y use
44 45 * xh*xh+(y*y+((x-xh)*(x+xh))) for x*x+y*y
45 46 * where xh = x with lower 32 bits cleared; else
46 47 * 3. if x <= 2y use
47 48 * x2h*yh+((x-y)*(x-y)+(x2h*(y-yh)+(x2-x2h)*y))
48 49 * where x2 = 2*x, x2h = 2x with lower 32 bits cleared, yh = y with
49 50 * lower 32 bits chopped.
50 51 *
51 52 * B. When rounding is not rounded-to-nearest:
52 53 * The following (magic) formula will yield an error less than 1 ulp.
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53 54 * z = sqrt(x * x + y * y)
54 55 * hypot(x, y) = x + (y / ((x + z) / y))
55 56 *
56 57 * NOTE: DO NOT remove parenthsis!
57 58 *
58 59 * Special cases:
59 60 * hypot(x, y) is INF if x or y is +INF or -INF; else
60 61 * hypot(x, y) is NAN if x or y is NAN.
61 62 *
62 63 * Accuracy:
63 - * hypot(x, y) returns sqrt(x^2+y^2) with error less than 1 ulps
64 + * hypot(x, y) returns sqrt(x^2+y^2) with error less than 1 ulps
64 65 * (units in the last place)
65 66 */
66 67
67 68 #include "libm.h"
68 69
69 -static const double
70 - zero = 0.0,
70 +static const double zero = 0.0,
71 71 onep1u = 1.00000000000000022204e+00, /* 0x3ff00000 1 = 1+2**-52 */
72 72 twom53 = 1.11022302462515654042e-16, /* 0x3ca00000 0 = 2**-53 */
73 73 twom768 = 6.441148769597133308e-232, /* 2^-768 */
74 - two768 = 1.552518092300708935e+231; /* 2^768 */
74 + two768 = 1.552518092300708935e+231; /* 2^768 */
75 75
76 -/* INDENT ON */
77 76
78 77 double
79 -hypot(double x, double y) {
78 +hypot(double x, double y)
79 +{
80 80 double xh, yh, w, ax, ay;
81 81 int i, j, nx, ny, ix, iy, iscale = 0;
82 82 unsigned lx, ly;
83 83
84 - ix = ((int *) &x)[HIWORD] & ~0x80000000;
85 - lx = ((int *) &x)[LOWORD];
86 - iy = ((int *) &y)[HIWORD] & ~0x80000000;
87 - ly = ((int *) &y)[LOWORD];
84 + ix = ((int *)&x)[HIWORD] & ~0x80000000;
85 + lx = ((int *)&x)[LOWORD];
86 + iy = ((int *)&y)[HIWORD] & ~0x80000000;
87 + ly = ((int *)&y)[LOWORD];
88 +
88 89 /*
89 90 * Force ax = |x| ~>~ ay = |y|
90 91 */
91 92 if (iy > ix) {
92 93 ax = fabs(y);
93 94 ay = fabs(x);
94 95 i = ix;
95 96 ix = iy;
96 97 iy = i;
97 98 i = lx;
98 99 lx = ly;
99 100 ly = i;
100 101 } else {
101 102 ax = fabs(x);
102 103 ay = fabs(y);
103 104 }
105 +
104 106 nx = ix >> 20;
105 107 ny = iy >> 20;
106 - j = nx - ny;
108 + j = nx - ny;
109 +
107 110 /*
108 111 * x >= 2^500 (x*x or y*y may overflow)
109 112 */
110 113 if (nx >= 0x5f3) {
111 114 if (nx == 0x7ff) { /* inf or NaN, signal of sNaN */
112 115 if (((ix - 0x7ff00000) | lx) == 0)
113 116 return (ax == ay ? ay : ax);
114 117 else if (((iy - 0x7ff00000) | ly) == 0)
115 118 return (ay == ax ? ax : ay);
116 119 else
117 120 return (ax * ay); /* + -> * for Cheetah */
118 - } else if (j > 32) { /* x >> y */
121 + } else if (j > 32) { /* x >> y */
119 122 if (j <= 53)
120 123 ay *= twom53;
124 +
121 125 ax += ay;
122 - if (((int *) &ax)[HIWORD] == 0x7ff00000)
126 +
127 + if (((int *)&ax)[HIWORD] == 0x7ff00000)
123 128 ax = _SVID_libm_err(x, y, 4);
129 +
124 130 return (ax);
125 131 }
132 +
126 133 ax *= twom768;
127 134 ay *= twom768;
128 135 iscale = 2;
129 136 ix -= 768 << 20;
130 137 iy -= 768 << 20;
131 138 }
139 +
132 140 /*
133 141 * y < 2^-450 (x*x or y*y may underflow)
134 142 */
135 143 else if (ny < 0x23d) {
136 144 if ((ix | lx) == 0)
137 145 return (ay);
146 +
138 147 if ((iy | ly) == 0)
139 148 return (ax);
140 - if (j > 53) /* x >> y */
149 +
150 + if (j > 53) /* x >> y */
141 151 return (ax + ay);
152 +
142 153 iscale = 1;
143 154 ax *= two768;
144 155 ay *= two768;
156 +
145 157 if (nx == 0) {
146 158 if (ax == zero) /* guard subnormal flush to zero */
147 159 return (ax);
148 - ix = ((int *) &ax)[HIWORD];
149 - } else
160 +
161 + ix = ((int *)&ax)[HIWORD];
162 + } else {
150 163 ix += 768 << 20;
164 + }
165 +
151 166 if (ny == 0) {
152 167 if (ay == zero) /* guard subnormal flush to zero */
153 168 return (ax * twom768);
154 - iy = ((int *) &ay)[HIWORD];
155 - } else
169 +
170 + iy = ((int *)&ay)[HIWORD];
171 + } else {
156 172 iy += 768 << 20;
173 + }
174 +
157 175 j = (ix >> 20) - (iy >> 20);
176 +
158 177 if (j > 32) { /* x >> y */
159 178 if (j <= 53)
160 179 ay *= twom53;
180 +
161 181 return ((ax + ay) * twom768);
162 182 }
163 183 } else if (j > 32) { /* x >> y */
164 184 if (j <= 53)
165 185 ay *= twom53;
186 +
166 187 return (ax + ay);
167 188 }
189 +
168 190 /*
169 191 * Medium range ax and ay with max{|ax/ay|,|ay/ax|} bounded by 2^32
170 192 * First check rounding mode by comparing onep1u*onep1u with onep1u+twom53.
171 193 * Make sure the computation is done at run-time.
172 194 */
173 195 if (((lx | ly) << 5) == 0) {
174 196 ay = ay * ay;
175 197 ax += ay / (ax + sqrt(ax * ax + ay));
176 - } else
177 - if (onep1u * onep1u != onep1u + twom53) {
178 - /* round-to-zero, positive, negative mode */
179 - /* magic formula with less than an ulp error */
198 + } else if (onep1u * onep1u != onep1u + twom53) {
199 + /*
200 + * round-to-zero, positive, negative mode
201 + * magic formula with less than an ulp error
202 + */
180 203 w = sqrt(ax * ax + ay * ay);
181 204 ax += ay / ((ax + w) / ay);
182 205 } else {
183 - /* round-to-nearest mode */
206 + /* round-to-nearest mode */
184 207 w = ax - ay;
208 +
185 209 if (w > ay) {
186 - ((int *) &xh)[HIWORD] = ix;
187 - ((int *) &xh)[LOWORD] = 0;
210 + ((int *)&xh)[HIWORD] = ix;
211 + ((int *)&xh)[LOWORD] = 0;
188 212 ay = ay * ay + (ax - xh) * (ax + xh);
189 213 ax = sqrt(xh * xh + ay);
190 214 } else {
191 215 ax = ax + ax;
192 - ((int *) &xh)[HIWORD] = ix + 0x00100000;
193 - ((int *) &xh)[LOWORD] = 0;
194 - ((int *) &yh)[HIWORD] = iy;
195 - ((int *) &yh)[LOWORD] = 0;
216 + ((int *)&xh)[HIWORD] = ix + 0x00100000;
217 + ((int *)&xh)[LOWORD] = 0;
218 + ((int *)&yh)[HIWORD] = iy;
219 + ((int *)&yh)[LOWORD] = 0;
196 220 ay = w * w + ((ax - xh) * yh + (ay - yh) * ax);
197 221 ax = sqrt(xh * yh + ay);
198 222 }
199 223 }
224 +
200 225 if (iscale > 0) {
201 - if (iscale == 1)
226 + if (iscale == 1) {
202 227 ax *= twom768;
203 - else {
228 + } else {
204 229 ax *= two768; /* must generate side effect here */
205 - if (((int *) &ax)[HIWORD] == 0x7ff00000)
230 +
231 + if (((int *)&ax)[HIWORD] == 0x7ff00000)
206 232 ax = _SVID_libm_err(x, y, 4);
207 233 }
208 234 }
235 +
209 236 return (ax);
210 237 }
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