| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _ASM_GENERIC_BITOPS_FLS64_H_ |
| #define _ASM_GENERIC_BITOPS_FLS64_H_ |
| |
| #include <asm/types.h> |
| |
| /** |
| * fls64 - find last set bit in a 64-bit word |
| * @x: the word to search |
| * |
| * This is defined in a similar way as the libc and compiler builtin |
| * ffsll, but returns the position of the most significant set bit. |
| * |
| * fls64(value) returns 0 if value is 0 or the position of the last |
| * set bit if value is nonzero. The last (most significant) bit is |
| * at position 64. |
| */ |
| #if BITS_PER_LONG == 32 |
| static __always_inline int fls64(__u64 x) |
| { |
| __u32 h = x >> 32; |
| if (h) |
| return fls(h) + 32; |
| return fls(x); |
| } |
| #elif BITS_PER_LONG == 64 |
| static __always_inline int fls64(__u64 x) |
| { |
| if (x == 0) |
| return 0; |
| return __fls(x) + 1; |
| } |
| #else |
| #error BITS_PER_LONG not 32 or 64 |
| #endif |
| |
| #endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */ |
