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/*
* Copyright (c) 1994 The University of Utah and
* the Center for Software Science (CSS). All rights reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* THE UNIVERSITY OF UTAH AND CSS ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
* IS" CONDITION. THE UNIVERSITY OF UTAH AND CSS DISCLAIM ANY LIABILITY OF
* ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* CSS requests users of this software to return to css-dist@cs.utah.edu any
* improvements that they make and grant CSS redistribution rights.
*
* Author: Bryan Ford, University of Utah CSS
*/
#ifndef _MACH_I386_PROC_OPS_H_
#define _MACH_I386_PROC_OPS_H_
#include <mach/machine/vm_types.h>
#include <mach/inline.h>
/* Returns the bit number of the most-significant set bit in `val',
e.g. 0 for 1, 1 for 2-3, 2 for 4-7, etc.
If `val' is 0 (i.e. no bits are set), the behavior is undefined. */
MACH_INLINE int find_msb_set(natural_t val)
{
int msb;
asm("
bsr %0,%0
" : "=r" (msb) : "0" (val));
return msb;
}
#endif _MACH_I386_PROC_OPS_H_
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