xref: /original-bsd/lib/libc/quad/lshrdi3.c (revision 3b6250d9)
1 /*-
2  * Copyright (c) 1992 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This software was developed by the Computer Systems Engineering group
6  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7  * contributed to Berkeley.
8  *
9  * %sccs.include.redist.c%
10  */
11 
12 #if defined(LIBC_SCCS) && !defined(lint)
13 static char sccsid[] = "@(#)lshrdi3.c	5.5 (Berkeley) 06/02/92";
14 #endif /* LIBC_SCCS and not lint */
15 
16 #include "quad.h"
17 
18 /*
19  * Shift an (unsigned) quad value right (logical shift right).
20  */
21 quad
22 __lshrdi3(quad a, u_quad shift)
23 {
24 	union uu aa;
25 
26 	aa.q = a;
27 	if (shift >= LONG_BITS) {
28 		aa.ul[L] = shift >= QUAD_BITS ? 0 :
29 		    aa.ul[H] >> (shift - LONG_BITS);
30 		aa.ul[H] = 0;
31 	} else if (shift > 0) {
32 		aa.ul[L] = (aa.ul[L] >> shift) |
33 		    (aa.ul[H] << (LONG_BITS - shift));
34 		aa.ul[H] >>= shift;
35 	}
36 	return (aa.q);
37 }
38