1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_GENERIC_BITOPS_BUILTIN_FLS_H_
3 #define _ASM_GENERIC_BITOPS_BUILTIN_FLS_H_
4
5 /**
6 * fls - find last (most-significant) bit set
7 * @x: the word to search
8 *
9 * This is defined the same way as ffs.
10 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
11 */
12 static __always_inline int fls(unsigned int x)
13 {
14 return x ? sizeof(x) * 8 - __builtin_clz(x) : 0;
15 }
16
17 #endif