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5261 libm should stop using synonyms.h
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--- old/usr/src/lib/libm/common/m9x/scalbln.c
+++ new/usr/src/lib/libm/common/m9x/scalbln.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.
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
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20 20 */
21 21
22 22 /*
23 23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
24 24 */
25 25 /*
26 26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
27 27 * Use is subject to license terms.
28 28 */
29 29
30 -#pragma weak scalbln = __scalbln
30 +#pragma weak __scalbln = scalbln
31 31
32 32 #include "libm.h"
33 33 #include <float.h> /* DBL_MAX, DBL_MIN */
34 34
35 35 static const double twom54 = 5.5511151231257827021181583404541015625e-17;
36 36 #if defined(__x86)
37 37 static const double two52 = 4503599627370496.0;
38 38 #else
39 39 /*
40 40 * Normalize non-zero subnormal x and return biased exponent of x in [-51,0]
41 41 */
42 42 static int
43 43 ilogb_biased(unsigned *px) {
44 44 int s = 52;
45 45 unsigned v = px[HIWORD] & ~0x80000000, w = px[LOWORD], t = v;
46 46
47 47 if (t)
48 48 s -= 32;
49 49 else
50 50 t = w;
51 51 if (t & 0xffff0000)
52 52 s -= 16, t >>= 16;
53 53 if (t & 0xff00)
54 54 s -= 8, t >>= 8;
55 55 if (t & 0xf0)
56 56 s -= 4, t >>= 4;
57 57 t <<= 1;
58 58 s -= (0xffffaa50 >> t) & 0x3;
59 59 if (s < 32) {
60 60 v = (v << s) | w >> (32 - s);
61 61 w <<= s;
62 62 } else {
63 63 v = w << (s - 32);
64 64 w = 0;
65 65 }
66 66 px[HIWORD] = (px[HIWORD] & 0x80000000) | v;
67 67 px[LOWORD] = w;
68 68 return (1 - s);
69 69 }
70 70 #endif /* defined(__x86) */
71 71
72 72 double
73 73 scalbln(double x, long n) {
74 74 int *px = (int *) &x, ix, k;
75 75
76 76 ix = px[HIWORD] & ~0x80000000;
77 77 k = ix >> 20;
78 78 if (k == 0x7ff)
79 79 #if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN)
80 80 return ((px[HIWORD] & 0x80000) != 0 ? x : x + x);
81 81 /* assumes sparc-like QNaN */
82 82 #else
83 83 return (x + x);
84 84 #endif
85 85 if ((px[LOWORD] | ix) == 0 || n == 0)
86 86 return (x);
87 87 if (k == 0) {
88 88 #if defined(__x86)
89 89 x *= two52;
90 90 k = ((px[HIWORD] & ~0x80000000) >> 20) - 52;
91 91 #else
92 92 k = ilogb_biased((unsigned *) px);
93 93 #endif
94 94 }
95 95 k += (int) n;
96 96 if (n > 5000 || k > 0x7fe)
97 97 return (DBL_MAX * copysign(DBL_MAX, x));
98 98 if (n < -5000 || k <= -54)
99 99 return (DBL_MIN * copysign(DBL_MIN, x));
100 100 if (k > 0) {
101 101 px[HIWORD] = (px[HIWORD] & ~0x7ff00000) | (k << 20);
102 102 return (x);
103 103 }
104 104 k += 54;
105 105 px[HIWORD] = (px[HIWORD] & ~0x7ff00000) | (k << 20);
106 106 return (x * twom54);
107 107 }
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