1 #ifndef _ASM_GENERIC_BITOPS_FLS_H_
2 #define _ASM_GENERIC_BITOPS_FLS_H_
3 
4 /**
5  * fls - find last (most-significant) bit set
6  * @x: the word to search
7  *
8  * This is defined the same way as ffs.
9  * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
10  */
11 
fls(int x)12 static __always_inline int fls(int x)
13 {
14 	int r = 32;
15 
16 	if (!x)
17 		return 0;
18 	if (!(x & 0xffff0000u)) {
19 		x <<= 16;
20 		r -= 16;
21 	}
22 	if (!(x & 0xff000000u)) {
23 		x <<= 8;
24 		r -= 8;
25 	}
26 	if (!(x & 0xf0000000u)) {
27 		x <<= 4;
28 		r -= 4;
29 	}
30 	if (!(x & 0xc0000000u)) {
31 		x <<= 2;
32 		r -= 2;
33 	}
34 	if (!(x & 0x80000000u)) {
35 		x <<= 1;
36 		r -= 1;
37 	}
38 	return r;
39 }
40 
41 #endif /* _ASM_GENERIC_BITOPS_FLS_H_ */
42