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11210 libm should be cstyle(1ONBLD) clean
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--- old/usr/src/lib/libm/common/LD/hypotl.c
+++ new/usr/src/lib/libm/common/LD/hypotl.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 __hypotl = hypotl
31 32
32 33 /*
33 34 * hypotl(x,y)
34 35 * Method :
35 36 * If z=x*x+y*y has error less than sqrt(2)/2 ulp than sqrt(z) has
36 37 * error less than 1 ulp.
37 38 * So, compute sqrt(x*x+y*y) with some care as follows:
38 39 * Assume x>y>0;
39 40 * 1. save and set rounding to round-to-nearest
40 41 * 2. if x > 2y use
41 42 * x1*x1+(y*y+(x2*(x+x2))) for x*x+y*y
42 43 * where x1 = x with lower 32 bits cleared, x2 = x-x1; else
43 44 * 3. if x <= 2y use
44 45 * t1*y1+((x-y)*(x-y)+(t1*y2+t2*y))
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45 46 * where t1 = 2x with lower 64 bits cleared, t2 = 2x-t1, y1= y with
46 47 * lower 32 bits cleared, y2 = y-y1.
47 48 *
48 49 * NOTE: DO NOT remove parenthsis!
49 50 *
50 51 * Special cases:
51 52 * hypot(x,y) is INF if x or y is +INF or -INF; else
52 53 * hypot(x,y) is NAN if x or y is NAN.
53 54 *
54 55 * Accuracy:
55 - * hypot(x,y) returns sqrt(x^2+y^2) with error less than 1 ulps (units
56 + * hypot(x,y) returns sqrt(x^2+y^2) with error less than 1 ulps (units
56 57 * in the last place)
57 58 */
58 59
59 60 #include "libm.h"
60 61
61 62 #if defined(__x86)
62 63 extern enum fp_direction_type __swap87RD(enum fp_direction_type);
63 64
64 65 #define k 0x7fff
65 66
66 67 long double
67 -hypotl(long double x, long double y) {
68 +hypotl(long double x, long double y)
69 +{
68 70 long double t1, t2, y1, y2, w;
69 - int *px = (int *) &x, *py = (int *) &y;
70 - int *pt1 = (int *) &t1, *py1 = (int *) &y1;
71 + int *px = (int *)&x, *py = (int *)&y;
72 + int *pt1 = (int *)&t1, *py1 = (int *)&y1;
71 73 enum fp_direction_type rd;
72 74 int j, nx, ny, nz;
73 75
74 76 px[2] &= 0x7fff; /* clear sign bit and padding bits of x and y */
75 77 py[2] &= 0x7fff;
76 78 nx = px[2]; /* biased exponent of x and y */
77 79 ny = py[2];
80 +
78 81 if (ny > nx) {
79 82 w = x;
80 83 x = y;
81 84 y = w;
82 85 nz = ny;
83 86 ny = nx;
84 87 nx = nz;
85 - } /* force nx >= ny */
88 + } /* force nx >= ny */
89 +
86 90 if (nx - ny >= 66)
87 91 return (x + y); /* x / y >= 2**65 */
92 +
88 93 if (nx < 0x5ff3 && ny > 0x205b) { /* medium x,y */
89 94 /* save and set RD to Rounding to nearest */
90 95 rd = __swap87RD(fp_nearest);
91 96 w = x - y;
97 +
92 98 if (w > y) {
93 99 pt1[2] = px[2];
94 100 pt1[1] = px[1];
95 101 pt1[0] = 0;
96 102 t2 = x - t1;
97 103 x = sqrtl(t1 * t1 - (y * (-y) - t2 * (x + t1)));
98 104 } else {
99 105 x += x;
100 106 py1[2] = py[2];
101 107 py1[1] = py[1];
102 108 py1[0] = 0;
103 109 y2 = y - y1;
104 110 pt1[2] = px[2];
105 111 pt1[1] = px[1];
106 112 pt1[0] = 0;
107 113 t2 = x - t1;
108 114 x = sqrtl(t1 * y1 - (w * (-w) - (t2 * y1 + y2 * x)));
109 115 }
116 +
110 117 if (rd != fp_nearest)
111 - __swap87RD(rd); /* restore rounding mode */
118 + __swap87RD(rd); /* restore rounding mode */
119 +
112 120 return (x);
113 121 } else {
114 122 if (nx == k || ny == k) { /* x or y is INF or NaN */
115 123 /* since nx >= ny; nx is always k within this block */
116 124 if (px[1] == 0x80000000 && px[0] == 0)
117 125 return (x);
118 126 else if (ny == k && py[1] == 0x80000000 && py[0] == 0)
119 127 return (y);
120 128 else
121 129 return (x + y);
122 130 }
131 +
123 132 if (ny == 0) {
124 133 if (y == 0.L || x == 0.L)
125 134 return (x + y);
135 +
126 136 pt1[2] = 0x3fff + 16381;
127 137 pt1[1] = 0x80000000;
128 138 pt1[0] = 0;
129 139 py1[2] = 0x3fff - 16381;
130 140 py1[1] = 0x80000000;
131 141 py1[0] = 0;
132 142 x *= t1;
133 143 y *= t1;
134 144 return (y1 * hypotl(x, y));
135 145 }
146 +
136 147 j = nx - 0x3fff;
137 148 px[2] -= j;
138 149 py[2] -= j;
139 150 pt1[2] = nx;
140 151 pt1[1] = 0x80000000;
141 152 pt1[0] = 0;
142 153 return (t1 * hypotl(x, y));
143 154 }
144 155 }
145 156 #endif
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