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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _ASM_GENERIC_BITOPS_FLS_H_
- #define _ASM_GENERIC_BITOPS_FLS_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 /* _ASM_GENERIC_BITOPS_FLS_H_ */
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