diff options
| -rw-r--r-- | include/linux/bitops.h | 124 |
1 files changed, 1 insertions, 123 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h index f17525a..5d1eabc 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -3,88 +3,11 @@ #include <asm/types.h> /* - * ffs: find first bit set. This is defined the same way as - * the libc and compiler builtin ffs routines, therefore - * differs in spirit from the above ffz (man ffs). - */ - -static inline int generic_ffs(int x) -{ - int r = 1; - - if (!x) - return 0; - if (!(x & 0xffff)) { - x >>= 16; - r += 16; - } - if (!(x & 0xff)) { - x >>= 8; - r += 8; - } - if (!(x & 0xf)) { - x >>= 4; - r += 4; - } - if (!(x & 3)) { - x >>= 2; - r += 2; - } - if (!(x & 1)) { - x >>= 1; - r += 1; - } - return r; -} - -/* - * fls: find last bit set. - */ - -static __inline__ int generic_fls(int x) -{ - int r = 32; - - if (!x) - return 0; - if (!(x & 0xffff0000u)) { - x <<= 16; - r -= 16; - } - if (!(x & 0xff000000u)) { - x <<= 8; - r -= 8; - } - if (!(x & 0xf0000000u)) { - x <<= 4; - r -= 4; - } - if (!(x & 0xc0000000u)) { - x <<= 2; - r -= 2; - } - if (!(x & 0x80000000u)) { - x <<= 1; - r -= 1; - } - return r; -} - -/* * Include this here because some architectures need generic_ffs/fls in * scope */ #include <asm/bitops.h> - -static inline int generic_fls64(__u64 x) -{ - __u32 h = x >> 32; - if (h) - return fls(h) + 32; - return fls(x); -} - static __inline__ int get_bitmask_order(unsigned int count) { int order; @@ -103,54 +26,9 @@ static __inline__ int get_count_order(unsigned int count) return order; } -/* - * hweightN: returns the hamming weight (i.e. the number - * of bits set) of a N-bit word - */ - -static inline unsigned int generic_hweight32(unsigned int w) -{ - unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555); - res = (res & 0x33333333) + ((res >> 2) & 0x33333333); - res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F); - res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF); - return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF); -} - -static inline unsigned int generic_hweight16(unsigned int w) -{ - unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555); - res = (res & 0x3333) + ((res >> 2) & 0x3333); - res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F); - return (res & 0x00FF) + ((res >> 8) & 0x00FF); -} - -static inline unsigned int generic_hweight8(unsigned int w) -{ - unsigned int res = (w & 0x55) + ((w >> 1) & 0x55); - res = (res & 0x33) + ((res >> 2) & 0x33); - return (res & 0x0F) + ((res >> 4) & 0x0F); -} - -static inline unsigned long generic_hweight64(__u64 w) -{ -#if BITS_PER_LONG < 64 - return generic_hweight32((unsigned int)(w >> 32)) + - generic_hweight32((unsigned int)w); -#else - u64 res; - res = (w & 0x5555555555555555ul) + ((w >> 1) & 0x5555555555555555ul); - res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul); - res = (res & 0x0F0F0F0F0F0F0F0Ful) + ((res >> 4) & 0x0F0F0F0F0F0F0F0Ful); - res = (res & 0x00FF00FF00FF00FFul) + ((res >> 8) & 0x00FF00FF00FF00FFul); - res = (res & 0x0000FFFF0000FFFFul) + ((res >> 16) & 0x0000FFFF0000FFFFul); - return (res & 0x00000000FFFFFFFFul) + ((res >> 32) & 0x00000000FFFFFFFFul); -#endif -} - static inline unsigned long hweight_long(unsigned long w) { - return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w); + return sizeof(w) == 4 ? hweight32(w) : hweight64(w); } /* |