xref: /titanic_52/usr/src/lib/libc/port/fp/lshrdi3.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate  * Copyright (c) 1992, 1993
3*7c478bd9Sstevel@tonic-gate  *	The Regents of the University of California.  All rights reserved.
4*7c478bd9Sstevel@tonic-gate  *
5*7c478bd9Sstevel@tonic-gate  * This software was developed by the Computer Systems Engineering group
6*7c478bd9Sstevel@tonic-gate  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7*7c478bd9Sstevel@tonic-gate  * contributed to Berkeley.
8*7c478bd9Sstevel@tonic-gate  *
9*7c478bd9Sstevel@tonic-gate  * Redistribution and use in source and binary forms, with or without
10*7c478bd9Sstevel@tonic-gate  * modification, are permitted provided that the following conditions
11*7c478bd9Sstevel@tonic-gate  * are met:
12*7c478bd9Sstevel@tonic-gate  * 1. Redistributions of source code must retain the above copyright
13*7c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer.
14*7c478bd9Sstevel@tonic-gate  * 2. Redistributions in binary form must reproduce the above copyright
15*7c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer in the
16*7c478bd9Sstevel@tonic-gate  *    documentation and/or other materials provided with the distribution.
17*7c478bd9Sstevel@tonic-gate  * 4. Neither the name of the University nor the names of its contributors
18*7c478bd9Sstevel@tonic-gate  *    may be used to endorse or promote products derived from this software
19*7c478bd9Sstevel@tonic-gate  *    without specific prior written permission.
20*7c478bd9Sstevel@tonic-gate  *
21*7c478bd9Sstevel@tonic-gate  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22*7c478bd9Sstevel@tonic-gate  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23*7c478bd9Sstevel@tonic-gate  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24*7c478bd9Sstevel@tonic-gate  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25*7c478bd9Sstevel@tonic-gate  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26*7c478bd9Sstevel@tonic-gate  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27*7c478bd9Sstevel@tonic-gate  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28*7c478bd9Sstevel@tonic-gate  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29*7c478bd9Sstevel@tonic-gate  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30*7c478bd9Sstevel@tonic-gate  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31*7c478bd9Sstevel@tonic-gate  * SUCH DAMAGE.
32*7c478bd9Sstevel@tonic-gate  */
33*7c478bd9Sstevel@tonic-gate 
34*7c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
35*7c478bd9Sstevel@tonic-gate 
36*7c478bd9Sstevel@tonic-gate #include "quadint.h"
37*7c478bd9Sstevel@tonic-gate 
38*7c478bd9Sstevel@tonic-gate #pragma weak __lshrdi3 = ___lshrdi3
39*7c478bd9Sstevel@tonic-gate 
40*7c478bd9Sstevel@tonic-gate /*
41*7c478bd9Sstevel@tonic-gate  * Shift an (unsigned) quad value right (logical shift right).
42*7c478bd9Sstevel@tonic-gate  */
43*7c478bd9Sstevel@tonic-gate longlong_t
44*7c478bd9Sstevel@tonic-gate ___lshrdi3(longlong_t a, qshift_t shift)
45*7c478bd9Sstevel@tonic-gate {
46*7c478bd9Sstevel@tonic-gate 	union uu aa;
47*7c478bd9Sstevel@tonic-gate 
48*7c478bd9Sstevel@tonic-gate 	aa.q = a;
49*7c478bd9Sstevel@tonic-gate 	if (shift >= LONG_BITS) {
50*7c478bd9Sstevel@tonic-gate 		aa.ul[L] = shift >= QUAD_BITS ? 0 :
51*7c478bd9Sstevel@tonic-gate 		    aa.ul[H] >> (shift - LONG_BITS);
52*7c478bd9Sstevel@tonic-gate 		aa.ul[H] = 0;
53*7c478bd9Sstevel@tonic-gate 	} else if (shift > 0) {
54*7c478bd9Sstevel@tonic-gate 		aa.ul[L] = (aa.ul[L] >> shift) |
55*7c478bd9Sstevel@tonic-gate 		    (aa.ul[H] << (LONG_BITS - shift));
56*7c478bd9Sstevel@tonic-gate 		aa.ul[H] >>= shift;
57*7c478bd9Sstevel@tonic-gate 	}
58*7c478bd9Sstevel@tonic-gate 	return (aa.q);
59*7c478bd9Sstevel@tonic-gate }
60