1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
24 */
25 /*
26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
27 * Use is subject to license terms.
28 */
29
30 #if defined(ELFOBJ)
31 #pragma weak lroundl = __lroundl
32 #endif
33
34 #include <sys/isa_defs.h> /* _ILP32 */
35 #include "libm.h"
36
37 #if defined(_ILP32)
38 #if defined(__sparc)
39 long
40 lroundl(long double x) {
41 union {
42 unsigned i[4];
43 long double q;
44 } xx;
45 union {
46 unsigned i;
47 float f;
48 } tt;
49 unsigned hx, sx, frac, l;
50 int j;
51
52 xx.q = x;
53 sx = xx.i[0] & 0x80000000;
54 hx = xx.i[0] & ~0x80000000;
55
56 /* handle trivial cases */
57 if (hx > 0x401e0000) { /* |x| > 2^31 + ... or x is nan */
58 /* convert an out-of-range float */
59 tt.i = sx | 0x7f000000;
60 return ((long) tt.f);
61 }
62
63 /* handle |x| < 1 */
64 if (hx < 0x3fff0000) {
65 if (hx >= 0x3ffe0000)
66 return (sx ? -1L : 1L);
67 return (0L);
68 }
69
70 /* extract the integer and fractional parts of x */
71 j = 0x406f - (hx >> 16); /* 91 <= j <= 112 */
72 xx.i[0] = 0x10000 | (xx.i[0] & 0xffff);
73 if (j >= 96) { /* 96 <= j <= 112 */
74 l = xx.i[0] >> (j - 96);
75 frac = ((xx.i[0] << 1) << (127 - j)) | (xx.i[1] >> (j - 96));
76 if (((xx.i[1] << 1) << (127 - j)) | xx.i[2] | xx.i[3])
77 frac |= 1;
78 } else { /* 91 <= j <= 95 */
79 l = (xx.i[0] << (96 - j)) | (xx.i[1] >> (j - 64));
80 frac = (xx.i[1] << (96 - j)) | (xx.i[2] >> (j - 64));
81 if ((xx.i[2] << (96 - j)) | xx.i[3])
82 frac |= 1;
83 }
84
85 /* round */
86 if (frac >= 0x80000000U)
87 l++;
88
89 /* check for result out of range (note that z is |x| at this point) */
90 if (l > 0x80000000U || (l == 0x80000000U && !sx)) {
91 tt.i = sx | 0x7f000000;
92 return ((long) tt.f);
93 }
94
95 /* negate result if need be */
96 if (sx)
97 l = -l;
98 return ((long) l);
99 }
100 #elif defined(__x86)
101 long
102 lroundl(long double x) {
103 union {
104 unsigned i[3];
105 long double e;
106 } xx;
107 int ex, sx, i;
108
109 xx.e = x;
110 ex = xx.i[2] & 0x7fff;
111 sx = xx.i[2] & 0x8000;
112 if (ex < 0x403e) { /* |x| < 2^63 */
113 if (ex < 0x3fff) { /* |x| < 1 */
114 if (ex >= 0x3ffe)
115 return (sx ? -1L : 1L);
116 return (0L);
117 }
118
119 /* round x at the integer bit */
120 if (ex < 0x401e) {
121 i = 1 << (0x401d - ex);
122 xx.i[1] = (xx.i[1] + i) & ~(i | (i - 1));
123 xx.i[0] = 0;
124 } else {
125 i = 1 << (0x403d - ex);
126 xx.i[0] += i;
127 if (xx.i[0] < i)
128 xx.i[1]++;
129 xx.i[0] &= ~(i | (i - 1));
130 }
131 if (xx.i[1] == 0) {
132 xx.i[2] = sx | ++ex;
133 xx.i[1] = 0x80000000U;
134 }
135 }
136
137 /* now x is nan, inf, or integral */
138 return ((long) xx.e);
139 }
140 #else
141 #error Unknown architecture
142 #endif /* defined(__sparc) || defined(__x86) */
143 #else
144 #error Unsupported architecture
145 #endif /* defined(_ILP32) */