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authorStephen Hemminger <shemminger@osdl.org>2005-12-21 19:31:36 -0800
committerDavid S. Miller <davem@sunset.davemloft.net>2006-01-03 13:11:07 -0800
commit90933fc8ba5cc9034e3c04ee19938a22b0b4fe4e (patch)
treee42a78d253b375025cf73efe0f582d2722619397 /include/asm-x86_64/bitops.h
parent3821af2fe13700cab6fd67367128fa180e43f8b8 (diff)
[FLS64]: x86_64 version
Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/asm-x86_64/bitops.h')
-rw-r--r--include/asm-x86_64/bitops.h28
1 files changed, 27 insertions, 1 deletions
diff --git a/include/asm-x86_64/bitops.h b/include/asm-x86_64/bitops.h
index 94b52c8ce97..a4d5d090945 100644
--- a/include/asm-x86_64/bitops.h
+++ b/include/asm-x86_64/bitops.h
@@ -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)
@@ -370,6 +384,19 @@ static __inline__ int ffs(int x)
}
/**
+ * 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__ */