| 1 | #ifndef FIO_FFZ_H |
| 2 | #define FIO_FFZ_H |
| 3 | |
| 4 | #include <inttypes.h> |
| 5 | |
| 6 | static inline int ffs64(uint64_t word) |
| 7 | { |
| 8 | int r = 0; |
| 9 | |
| 10 | if ((word & 0xffffffff) == 0) { |
| 11 | r += 32; |
| 12 | word >>= 32; |
| 13 | } |
| 14 | if (!(word & 0xffff)) { |
| 15 | word >>= 16; |
| 16 | r += 16; |
| 17 | } |
| 18 | if (!(word & 0xff)) { |
| 19 | word >>= 8; |
| 20 | r += 8; |
| 21 | } |
| 22 | if (!(word & 0xf)) { |
| 23 | word >>= 4; |
| 24 | r += 4; |
| 25 | } |
| 26 | if (!(word & 3)) { |
| 27 | word >>= 2; |
| 28 | r += 2; |
| 29 | } |
| 30 | if (!(word & 1)) { |
| 31 | word >>= 1; |
| 32 | r += 1; |
| 33 | } |
| 34 | |
| 35 | return r; |
| 36 | } |
| 37 | |
| 38 | #ifndef ARCH_HAVE_FFZ |
| 39 | |
| 40 | static inline int ffz(unsigned long bitmask) |
| 41 | { |
| 42 | return ffs64(~bitmask); |
| 43 | } |
| 44 | |
| 45 | #else |
| 46 | #define ffz(bitmask) arch_ffz(bitmask) |
| 47 | #endif |
| 48 | |
| 49 | static inline int ffz64(uint64_t bitmask) |
| 50 | { |
| 51 | return ffs64(~bitmask); |
| 52 | } |
| 53 | |
| 54 | #endif |