diff options
| author | Robert Richter <robert.richter@amd.com> | 2010-04-23 14:30:22 +0200 |
|---|---|---|
| committer | Robert Richter <robert.richter@amd.com> | 2010-04-23 14:30:22 +0200 |
| commit | a36bf32e9e8a86f291f746b7f8292e042ee04a46 (patch) | |
| tree | c5c999baa4c214218e3adea9b336cbd9f23950ad /include/linux/bitops.h | |
| parent | bc078e4eab65f11bbaeed380593ab8151b30d703 (diff) | |
| parent | 01bf0b64579ead8a82e7cfc32ae44bc667e7ad0f (diff) | |
Merge commit 'v2.6.34-rc5' into oprofile/core
Diffstat (limited to 'include/linux/bitops.h')
| -rw-r--r-- | include/linux/bitops.h | 32 |
1 files changed, 28 insertions, 4 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h index c05a29cb9bb2..b796eab5ca75 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -16,16 +16,15 @@ */ #include <asm/bitops.h> -#define for_each_bit(bit, addr, size) \ +#define for_each_set_bit(bit, addr, size) \ for ((bit) = find_first_bit((addr), (size)); \ (bit) < (size); \ (bit) = find_next_bit((addr), (size), (bit) + 1)) - static __inline__ int get_bitmask_order(unsigned int count) { int order; - + order = fls(count); return order; /* We could be slightly more clever with -1 here... */ } @@ -33,7 +32,7 @@ static __inline__ int get_bitmask_order(unsigned int count) static __inline__ int get_count_order(unsigned int count) { int order; - + order = fls(count) - 1; if (count & (count - 1)) order++; @@ -45,6 +44,31 @@ static inline unsigned long hweight_long(unsigned long w) return sizeof(w) == 4 ? hweight32(w) : hweight64(w); } +/* + * Clearly slow versions of the hweightN() functions, their benefit is + * of course compile time evaluation of constant arguments. + */ +#define HWEIGHT8(w) \ + ( BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + \ + (!!((w) & (1ULL << 0))) + \ + (!!((w) & (1ULL << 1))) + \ + (!!((w) & (1ULL << 2))) + \ + (!!((w) & (1ULL << 3))) + \ + (!!((w) & (1ULL << 4))) + \ + (!!((w) & (1ULL << 5))) + \ + (!!((w) & (1ULL << 6))) + \ + (!!((w) & (1ULL << 7))) ) + +#define HWEIGHT16(w) (HWEIGHT8(w) + HWEIGHT8((w) >> 8)) +#define HWEIGHT32(w) (HWEIGHT16(w) + HWEIGHT16((w) >> 16)) +#define HWEIGHT64(w) (HWEIGHT32(w) + HWEIGHT32((w) >> 32)) + +/* + * Type invariant version that simply casts things to the + * largest type. + */ +#define HWEIGHT(w) HWEIGHT64((u64)(w)) + /** * rol32 - rotate a 32-bit value left * @word: value to rotate |