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 #pragma weak llroundl = __llroundl
31 #if defined(__sparcv9) || defined(__amd64)
32 #pragma weak lroundl = __llroundl
33 #pragma weak __lroundl = __llroundl
34 #endif
35
36 #include "libm.h"
37
38 #if defined(__sparc)
39 long long
40 llroundl(long double x) {
41 union {
42 unsigned i[4];
43 long double q;
44 } xx;
45 union {
46 unsigned i[2];
47 long long l;
48 } zz;
49 union {
50 unsigned i;
51 float f;
52 } tt;
53 unsigned hx, sx, frac;
54 int j;
55
56 xx.q = x;
57 sx = xx.i[0] & 0x80000000;
58 hx = xx.i[0] & ~0x80000000;
59
60 /* handle trivial cases */
61 if (hx > 0x403e0000) { /* |x| > 2^63 + ... or x is nan */
62 /* convert an out-of-range float */
63 tt.i = sx | 0x7f000000;
64 return ((long long) tt.f);
65 }
66
67 /* handle |x| < 1 */
68 if (hx < 0x3fff0000) {
69 if (hx >= 0x3ffe0000)
70 return (sx ? -1LL : 1LL);
71 return (0LL);
72 }
73
74 /* extract the integer and fractional parts of x */
75 j = 0x406f - (hx >> 16);
76 xx.i[0] = 0x10000 | (xx.i[0] & 0xffff);
77 if (j >= 96) {
78 zz.i[0] = 0;
79 zz.i[1] = xx.i[0] >> (j - 96);
80 frac = ((xx.i[0] << 1) << (127 - j)) | (xx.i[1] >> (j - 96));
81 if (((xx.i[1] << 1) << (127 - j)) | xx.i[2] | xx.i[3])
82 frac |= 1;
83 } else if (j >= 64) {
84 zz.i[0] = xx.i[0] >> (j - 64);
85 zz.i[1] = ((xx.i[0] << 1) << (95 - j)) | (xx.i[1] >> (j - 64));
86 frac = ((xx.i[1] << 1) << (95 - j)) | (xx.i[2] >> (j - 64));
87 if (((xx.i[2] << 1) << (95 - j)) | xx.i[3])
88 frac |= 1;
89 } else {
90 zz.i[0] = ((xx.i[0] << 1) << (63 - j)) | (xx.i[1] >> (j - 32));
91 zz.i[1] = ((xx.i[1] << 1) << (63 - j)) | (xx.i[2] >> (j - 32));
92 frac = ((xx.i[2] << 1) << (63 - j)) | (xx.i[3] >> (j - 32));
93 if ((xx.i[3] << 1) << (63 - j))
94 frac |= 1;
95 }
96
97 /* round */
98 if (frac >= 0x80000000u) {
99 if (++zz.i[1] == 0)
100 zz.i[0]++;
101 }
102
103 /* check for result out of range (note that z is |x| at this point) */
104 if (zz.i[0] > 0x80000000u || (zz.i[0] == 0x80000000 && (zz.i[1] ||
105 !sx))) {
106 tt.i = sx | 0x7f000000;
107 return ((long long) tt.f);
108 }
109
110 /* negate result if need be */
111 if (sx) {
112 zz.i[0] = ~zz.i[0];
113 zz.i[1] = -zz.i[1];
114 if (zz.i[1] == 0)
115 zz.i[0]++;
116 }
117
118 return (zz.l);
119 }
120 #elif defined(__x86)
121 long long
122 llroundl(long double x) {
123 union {
124 unsigned i[3];
125 long double e;
126 } xx;
127 int ex, sx, i;
128
129 xx.e = x;
130 ex = xx.i[2] & 0x7fff;
131 sx = xx.i[2] & 0x8000;
132
133 if (ex < 0x403e) { /* |x| < 2^63 */
134 /* handle |x| < 1 */
135 if (ex < 0x3fff) {
136 if (ex >= 0x3ffe)
137 return (sx ? -1LL : 1LL);
138 return (0LL);
139 }
140
141 /* round x at the integer bit */
142 if (ex < 0x401e) {
143 i = 1 << (0x401d - ex);
144 xx.i[1] = (xx.i[1] + i) & ~(i | (i - 1));
145 xx.i[0] = 0;
146 } else {
147 i = 1 << (0x403d - ex);
148 xx.i[0] += i;
149 if (xx.i[0] < i)
150 xx.i[1]++;
151 xx.i[0] &= ~(i | (i - 1));
152 }
153 if (xx.i[1] == 0) {
154 xx.i[2] = sx | ++ex;
155 xx.i[1] = 0x80000000U;
156 }
157 }
158
159 /* now x is nan, inf, or integral */
160 return ((long long) xx.e);
161 }
162 #else
163 #error Unknown architecture
164 #endif