xref: /titanic_41/usr/src/lib/libc/i386/gen/lshiftl.s (revision d15447b6c777a1b2223924443bf36c9c8efb2ea4)
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 2008 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	.file	"%M%"
30
31/ Shift a double long value.
32
33#include "SYS.h"
34
35	.set	arg,8
36	.set	cnt,16
37	.set	ans,0
38
39	ENTRY(lshiftl)
40	popl	%eax
41	xchgl	%eax,0(%esp)
42
43	pushl	%eax
44	movl	arg(%esp),%eax
45	movl	arg+4(%esp),%edx
46	movl	cnt(%esp),%ecx
47	orl	%ecx,%ecx
48	jz	.lshiftld
49	jns	.lshiftlp
50
51/ We are doing a negative (right) shift
52
53	negl	%ecx
54
55.lshiftln:
56	sarl	$1,%edx
57	rcrl	$1,%eax
58	loop	.lshiftln
59	jmp	.lshiftld
60
61/ We are doing a positive (left) shift
62
63.lshiftlp:
64	shll	$1,%eax
65	rcll	$1,%edx
66	loop	.lshiftlp
67
68/ We are done.
69
70.lshiftld:
71	movl	%eax,%ecx
72	popl	%eax
73	movl	%ecx,ans(%eax)
74	movl	%edx,ans+4(%eax)
75
76	ret
77	SET_SIZE(lshiftl)
78