diff options
Diffstat (limited to 'include/asm-ia64/bitops.h')
| -rw-r--r-- | include/asm-ia64/bitops.h | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/include/asm-ia64/bitops.h b/include/asm-ia64/bitops.h index 925d54cee475..7232528e2d0c 100644 --- a/include/asm-ia64/bitops.h +++ b/include/asm-ia64/bitops.h @@ -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); } /* |