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 llrintl = __llrintl
32 #if defined(__sparcv9) || defined(__amd64)
33 #pragma weak lrintl = __llrintl
34 #pragma weak __lrintl = __llrintl
35 #endif
36 #endif
37
38 #include "libm.h"
39
40 #if defined(__sparc)
41
42 #include "fma.h"
43 #include "fenv_inlines.h"
44
45 long long
46 llrintl(long double x) {
47 union {
48 unsigned i[4];
49 long double q;
50 } xx;
51 union {
52 unsigned i[2];
53 long long l;
54 } zz;
55 union {
56 unsigned i;
57 float f;
58 } tt;
59 unsigned int hx, sx, frac;
60 unsigned int fsr;
61 int rm, j;
62 volatile float dummy;
63
64 xx.q = x;
65 sx = xx.i[0] & 0x80000000;
66 hx = xx.i[0] & ~0x80000000;
67
68 /* handle trivial cases */
69 if (hx > 0x403e0000) { /* |x| > 2^63 + ... or x is nan */
70 /* convert an out-of-range float */
71 tt.i = sx | 0x7f000000;
72 return ((long long) tt.f);
73 } else if ((hx | xx.i[1] | xx.i[2] | xx.i[3]) == 0) /* x is zero */
74 return (0LL);
75
76 /* get the rounding mode */
77 __fenv_getfsr32(&fsr);
78 rm = fsr >> 30;
79
80 /* flip the sense of directed roundings if x is negative */
81 if (sx)
82 rm ^= rm >> 1;
83
84 /* handle |x| < 1 */
85 if (hx < 0x3fff0000) {
86 dummy = 1.0e30f; /* x is nonzero, so raise inexact */
87 dummy += 1.0e-30f;
88 if (rm == FSR_RP || (rm == FSR_RN && (hx >= 0x3ffe0000 &&
89 ((hx & 0xffff) | xx.i[1] | xx.i[2] | xx.i[3]))))
90 return (sx ? -1LL : 1LL);
91 return (0LL);
92 }
93
94 /* extract the integer and fractional parts of x */
95 j = 0x406f - (hx >> 16);
96 xx.i[0] = 0x10000 | (xx.i[0] & 0xffff);
97 if (j >= 96) {
98 zz.i[0] = 0;
99 zz.i[1] = xx.i[0] >> (j - 96);
100 frac = ((xx.i[0] << 1) << (127 - j)) | (xx.i[1] >> (j - 96));
101 if (((xx.i[1] << 1) << (127 - j)) | xx.i[2] | xx.i[3])
102 frac |= 1;
103 } else if (j >= 64) {
104 zz.i[0] = xx.i[0] >> (j - 64);
105 zz.i[1] = ((xx.i[0] << 1) << (95 - j)) | (xx.i[1] >> (j - 64));
106 frac = ((xx.i[1] << 1) << (95 - j)) | (xx.i[2] >> (j - 64));
107 if (((xx.i[2] << 1) << (95 - j)) | xx.i[3])
108 frac |= 1;
109 } else {
110 zz.i[0] = ((xx.i[0] << 1) << (63 - j)) | (xx.i[1] >> (j - 32));
111 zz.i[1] = ((xx.i[1] << 1) << (63 - j)) | (xx.i[2] >> (j - 32));
112 frac = ((xx.i[2] << 1) << (63 - j)) | (xx.i[3] >> (j - 32));
113 if ((xx.i[3] << 1) << (63 - j))
114 frac |= 1;
115 }
116
117 /* round */
118 if (frac && (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000u ||
119 (frac == 0x80000000 && (zz.i[1] & 1)))))) {
120 if (++zz.i[1] == 0)
121 zz.i[0]++;
122 }
123
124 /* check for result out of range (note that z is |x| at this point) */
125 if (zz.i[0] > 0x80000000u || (zz.i[0] == 0x80000000 && (zz.i[1] ||
126 !sx))) {
127 tt.i = sx | 0x7f000000;
128 return ((long long) tt.f);
129 }
130
131 /* raise inexact if need be */
132 if (frac) {
133 dummy = 1.0e30F;
134 dummy += 1.0e-30F;
135 }
136
137 /* negate result if need be */
138 if (sx) {
139 zz.i[0] = ~zz.i[0];
140 zz.i[1] = -zz.i[1];
141 if (zz.i[1] == 0)
142 zz.i[0]++;
143 }
144 return (zz.l);
145 }
146 #elif defined(__x86)
147 long long
148 llrintl(long double x) {
149 /*
150 * Note: The following code works on x86 (in the default rounding
151 * precision mode), but one ought to just use the fistpll instruction
152 * instead.
153 */
154 union {
155 unsigned i[3];
156 long double e;
157 } xx, yy;
158 int ex;
159
160 xx.e = x;
161 ex = xx.i[2] & 0x7fff;
162
163 if (ex < 0x403e) { /* |x| < 2^63 */
164 /* add and subtract a power of two to round x to an integer */
165 yy.i[2] = (xx.i[2] & 0x8000) | 0x403e;
166 yy.i[1] = 0x80000000;
167 yy.i[0] = 0;
168 x = (x + yy.e) - yy.e;
169 }
170
171 /* now x is nan, inf, or integral */
172 return ((long long) x);
173 }
174 #else
175 #error Unknown architecture
176 #endif