提交 8d134db0 编写于 作者: L Linus Torvalds
......@@ -314,8 +314,8 @@ __ffs (unsigned long x)
#ifdef __KERNEL__
/*
* find_last_zero_bit - find the last zero bit in a 64 bit quantity
* @x: The value to search
* Return bit number of last (most-significant) bit set. Undefined
* for x==0. Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
*/
static inline unsigned long
ia64_fls (unsigned long x)
......@@ -327,10 +327,23 @@ ia64_fls (unsigned long x)
return exp - 0xffff;
}
/*
* Find the last (most significant) bit set. Returns 0 for x==0 and
* bits are numbered from 1..32 (e.g., fls(9) == 4).
*/
static inline int
fls (int x)
fls (int t)
{
return ia64_fls((unsigned int) x);
unsigned long x = t & 0xffffffffu;
if (!x)
return 0;
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
return ia64_popcnt(x);
}
/*
......
......@@ -133,13 +133,17 @@ register unsigned long ia64_r13 asm ("r13") __attribute_used__;
ia64_intri_res; \
})
#define ia64_popcnt(x) \
({ \
#if __GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
# define ia64_popcnt(x) __builtin_popcountl(x)
#else
# define ia64_popcnt(x) \
({ \
__u64 ia64_intri_res; \
asm ("popcnt %0=%1" : "=r" (ia64_intri_res) : "r" (x)); \
\
ia64_intri_res; \
})
})
#endif
#define ia64_getf_exp(x) \
({ \
......
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