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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright (c) 1994-1997, by Sun Microsystems, Inc.
24 * All rights reserved.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 #include "quad.h"
30
31 #ifdef __sparcv9
32
33 /*
34 * _Qp_dtoq(pz, x) sets *pz = (long double)x.
35 */
36 void
_Qp_dtoq(union longdouble * pz,double x)37 _Qp_dtoq(union longdouble *pz, double x)
38
39 #else
40
41 /*
42 * _Q_dtoq(x) returns (long double)x.
43 */
44 union longdouble
45 _Q_dtoq(double x)
46
47 #endif /* __sparcv9 */
48
49 {
50 #ifndef __sparcv9
51 union longdouble z;
52 #endif
53 union xdouble u;
54 unsigned int m, lhi, llo, fsr;
55
56 /* extract the exponent */
57 u.d = x;
58 m = ((u.l.hi & 0x7ff00000) >> 4) + 0x3c000000;
59 if (m == 0x3c000000) {
60 /* x is zero or denormal */
61 if ((u.l.hi & 0xfffff) | u.l.lo) {
62 /* x is denormal, normalize it */
63 m = 0x3c010000;
64 lhi = u.l.hi & 0xfffff;
65 llo = u.l.lo;
66 do {
67 lhi = (lhi << 1) | (llo >> 31);
68 llo <<= 1;
69 m -= 0x10000;
70 } while ((lhi & 0x7ff00000) == 0);
71 u.l.hi = (u.l.hi & 0x80000000) | lhi;
72 u.l.lo = llo;
73 } else {
74 m = 0;
75 }
76 } else if (m == 0x43ff0000) {
77 /* x is inf or nan */
78 m = 0x7fff0000;
79 if (((u.l.hi & 0x7ffff) | u.l.lo) && (u.l.hi & 0x80000) == 0) {
80 /* snan, signal invalid */
81 __quad_getfsrp(&fsr);
82 if (fsr & FSR_NVM) {
83 __quad_fdtoq(&x, &Z);
84 QUAD_RETURN(Z);
85 } else {
86 fsr = (fsr & ~FSR_CEXC) | FSR_NVA | FSR_NVC;
87 __quad_setfsrp(&fsr);
88 }
89 u.l.hi |= 0x80000;
90 }
91 }
92 Z.l.msw = m | (u.l.hi & 0x80000000) | ((u.l.hi & 0xffff0) >> 4);
93 Z.l.frac2 = (u.l.hi << 28) | (u.l.lo >> 4);
94 Z.l.frac3 = u.l.lo << 28;
95 Z.l.frac4 = 0;
96 QUAD_RETURN(Z);
97 }
98