1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _ASM_GENERIC_BITOPS_FLS_H_
 3#define _ASM_GENERIC_BITOPS_FLS_H_
 4
 5/**
 6 * generic_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
13static __always_inline int generic_fls(unsigned int x)
14{
15	int r = 32;
16
17	if (!x)
18		return 0;
19	if (!(x & 0xffff0000u)) {
20		x <<= 16;
21		r -= 16;
22	}
23	if (!(x & 0xff000000u)) {
24		x <<= 8;
25		r -= 8;
26	}
27	if (!(x & 0xf0000000u)) {
28		x <<= 4;
29		r -= 4;
30	}
31	if (!(x & 0xc0000000u)) {
32		x <<= 2;
33		r -= 2;
34	}
35	if (!(x & 0x80000000u)) {
36		x <<= 1;
37		r -= 1;
38	}
39	return r;
40}
41
42#ifndef __HAVE_ARCH_FLS
43#define fls(x) generic_fls(x)
44#endif
45
46#endif /* _ASM_GENERIC_BITOPS_FLS_H_ */

 
 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
12static __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_ */