| // NOLINT(legal/copyright) |
| |
| /* Duplicated under the terms of the GPLv2 from |
| * linux-kernel:/include/asm-generic/bitops/fls.h |
| */ |
| #ifndef VERITY_INCLUDE_ASM_GENERIC_BITOPS_FLS_H_ |
| #define VERITY_INCLUDE_ASM_GENERIC_BITOPS_FLS_H_ |
| |
| #include <linux/stddef.h> |
| |
| /** |
| * fls - find last (most-significant) bit set |
| * @x: the word to search |
| * |
| * This is defined the same way as ffs. |
| * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. |
| */ |
| |
| static __always_inline int 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; |
| } |
| |
| #endif // VERITY_INCLUDE_ASM_GENERIC_BITOPS_FLS_H_ |
