diff options
Diffstat (limited to 'include/asm-powerpc/bitops.h')
| -rw-r--r-- | include/asm-powerpc/bitops.h | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/include/asm-powerpc/bitops.h b/include/asm-powerpc/bitops.h index c341063d0804..8f757f6246e4 100644 --- a/include/asm-powerpc/bitops.h +++ b/include/asm-powerpc/bitops.h @@ -190,7 +190,8 @@ static __inline__ void set_bits(unsigned long mask, unsigned long *addr) * Return the zero-based bit position (LE, not IBM bit numbering) of * the most significant 1-bit in a double word. */ -static __inline__ int __ilog2(unsigned long x) +static __inline__ __attribute__((const)) +int __ilog2(unsigned long x) { int lz; @@ -198,6 +199,24 @@ static __inline__ int __ilog2(unsigned long x) return BITS_PER_LONG - 1 - lz; } +static inline __attribute__((const)) +int __ilog2_u32(u32 n) +{ + int bit; + asm ("cntlzw %0,%1" : "=r" (bit) : "r" (n)); + return 31 - bit; +} + +#ifdef __powerpc64__ +static inline __attribute__((const)) +int __ilog2_u64(u64 n) +{ + int bit; + asm ("cntlzd %0,%1" : "=r" (bit) : "r" (n)); + return 63 - bit; +} +#endif + /* * Determines the bit position of the least significant 0 bit in the * specified double word. The returned bit position will be |