1 /*
2  * Copyright (c) 2000, 2002 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32 #ifndef __XFS_BIT_H__
33 #define	__XFS_BIT_H__
34 
35 /*
36  * XFS bit manipulation routines.
37  */
38 
39 /*
40  * masks with n high/low bits set, 32-bit values & 64-bit values
41  */
42 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK32HI)
43 __uint32_t xfs_mask32hi(int n);
44 #define	XFS_MASK32HI(n)		xfs_mask32hi(n)
45 #else
46 #define	XFS_MASK32HI(n)		((__uint32_t)-1 << (32 - (n)))
47 #endif
48 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK64HI)
49 __uint64_t xfs_mask64hi(int n);
50 #define	XFS_MASK64HI(n)		xfs_mask64hi(n)
51 #else
52 #define	XFS_MASK64HI(n)		((__uint64_t)-1 << (64 - (n)))
53 #endif
54 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK32LO)
55 __uint32_t xfs_mask32lo(int n);
56 #define	XFS_MASK32LO(n)		xfs_mask32lo(n)
57 #else
58 #define	XFS_MASK32LO(n)		(((__uint32_t)1 << (n)) - 1)
59 #endif
60 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK64LO)
61 __uint64_t xfs_mask64lo(int n);
62 #define	XFS_MASK64LO(n)		xfs_mask64lo(n)
63 #else
64 #define	XFS_MASK64LO(n)		(((__uint64_t)1 << (n)) - 1)
65 #endif
66 
67 /* Get high bit set out of 32-bit argument, -1 if none set */
68 extern int xfs_highbit32(__uint32_t v);
69 
70 /* Get low bit set out of 64-bit argument, -1 if none set */
71 extern int xfs_lowbit64(__uint64_t v);
72 
73 /* Get high bit set out of 64-bit argument, -1 if none set */
74 extern int xfs_highbit64(__uint64_t);
75 
76 /* Count set bits in map starting with start_bit */
77 extern int xfs_count_bits(uint *map, uint size, uint start_bit);
78 
79 /* Count continuous one bits in map starting with start_bit */
80 extern int xfs_contig_bits(uint *map, uint size, uint start_bit);
81 
82 /* Find next set bit in map */
83 extern int xfs_next_bit(uint *map, uint size, uint start_bit);
84 
85 #endif	/* __XFS_BIT_H__ */
86