xref: /titanic_52/usr/src/lib/libbc/libc/gen/common/_Q_qtou.c (revision 5d54f3d8999eac1762fe0a8c7177d20f1f201fae)
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 1995 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include "_Qquad.h"
30 #include "_Qglobals.h"
31 
32 unsigned
33 _Q_qtou(QUAD x)
34 {
35 	unpacked	px;
36 	QUAD		c;
37 	unsigned	u,*pc = (unsigned*)&c,r;
38 	enum fp_direction_type saved_fp_direction = fp_direction;
39 
40 	pc[0] = 0x401e0000; pc[1]=pc[2]=pc[3]=0;	/* c = 2^31 */
41 	r = 0;
42 	u = *(int*)&x;	/* high part of x */
43 	if(u>=0x401e0000&&u<0x401f0000) {
44 		r = 0x80000000;
45 		x = _Q_sub(x,c);
46 	}
47 
48 	_fp_current_exceptions = 0;
49 	fp_direction = fp_tozero;
50 	_fp_unpack(&px, (int *)&x,fp_op_extended);
51 	_fp_pack(&px, (int *)&u,fp_op_integer);
52 	_Q_set_exception(_fp_current_exceptions);
53 	fp_direction = saved_fp_direction;
54 	return (u|r);
55 }
56