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[FLS64]: x86_64 version

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Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2005-12-21 19:31:36 -08:00 committed by David S. Miller
parent 3821af2fe1
commit 90933fc8ba
1 changed files with 27 additions and 1 deletions
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28
include/asm-x86_64/bitops.h
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@ -340,6 +340,20 @@ static __inline__ unsigned long __ffs(unsigned long word)
return word;
}
/*
* __fls: find last bit set.
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static __inline__ unsigned long __fls(unsigned long word)
{
__asm__("bsrq %1,%0"
:"=r" (word)
:"rm" (word));
return word;
}
#ifdef __KERNEL__
static inline int sched_find_first_bit(const unsigned long *b)
@ -369,6 +383,19 @@ static __inline__ int ffs(int x)
return r+1;
}
/**
* fls64 - find last bit set in 64 bit word
* @x: the word to search
*
* This is defined the same way as fls.
*/
static __inline__ int fls64(__u64 x)
{
if (x == 0)
return 0;
return __fls(x) + 1;
}
/**
* hweightN - returns the hamming weight of a N-bit word
* @x: the word to weigh
@ -409,7 +436,6 @@ static __inline__ int ffs(int x)
/* find last set bit */
#define fls(x) generic_fls(x)
#define fls64(x) generic_fls64(x)
#endif /* __KERNEL__ */