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Turn some macros into functions for 32-bit kernels, to save some memory.

#ifndef _FS_XFS_BIT_H
#define	_FS_XFS_BIT_H

#ident "$Revision: 1.3 $"

/*
 * XFS bit manipulation routines.
 */

/*
 * masks with n high/low bits set, 32-bit values & 64-bit values
 */
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK32HI)
__uint32_t xfs_mask32hi(int n);
#define	XFS_MASK32HI(n)		xfs_mask32hi(n)
#else
#define	XFS_MASK32HI(n)		((__uint32_t)-1 << (32 - (n)))
#endif
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK64HI)
__uint64_t xfs_mask64hi(int n);
#define	XFS_MASK64HI(n)		xfs_mask64hi(n)
#else
#define	XFS_MASK64HI(n)		((__uint64_t)-1 << (64 - (n)))
#endif
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK32LO)
__uint32_t xfs_mask32lo(int n);
#define	XFS_MASK32LO(n)		xfs_mask32lo(n)
#else
#define	XFS_MASK32LO(n)		(((__uint32_t)1 << (n)) - 1)
#endif
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK64LO)
__uint64_t xfs_mask64lo(int n);
#define	XFS_MASK64LO(n)		xfs_mask64lo(n)
#else
#define	XFS_MASK64LO(n)		(((__uint64_t)1 << (n)) - 1)
#endif

/*
 * Index of low bit number in byte, -1 for none set, 0..7 otherwise.
 */
extern const char xfs_lowbit[256];

/*
 * Index of high bit number in byte, -1 for none set, 0..7 otherwise.
 */
extern const char xfs_highbit[256];

/*
 * Count of bits set in byte, 0..8.
 */
extern const char xfs_countbit[256];

/*
 * xfs_lowbit32: get low bit set out of 32-bit argument, -1 if none set.
 */
extern int xfs_lowbit32(__uint32_t v);

/*
 * xfs_highbit32: get high bit set out of 32-bit argument, -1 if none set.
 */
extern int xfs_highbit32(__uint32_t v);

/*
 * xfs_lowbit64: get low bit set out of 64-bit argument, -1 if none set.
 */
extern int xfs_lowbit64(__uint64_t v);

/*
 * xfs_highbit64: get high bit set out of 64-bit argument, -1 if none set.
 */
extern int xfs_highbit64(__uint64_t);

#endif	/* _FS_XFS_BIT_H */