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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _ASM_GENERIC_BITOPS___FLS_H_3#define _ASM_GENERIC_BITOPS___FLS_H_4 5#include <asm/types.h>6 7/**8 * generic___fls - find last (most-significant) set bit in a long word9 * @word: the word to search10 *11 * Undefined if no set bit exists, so code should check against 0 first.12 */13static __always_inline unsigned int generic___fls(unsigned long word)14{15 unsigned int num = BITS_PER_LONG - 1;16 17#if BITS_PER_LONG == 6418 if (!(word & (~0ul << 32))) {19 num -= 32;20 word <<= 32;21 }22#endif23 if (!(word & (~0ul << (BITS_PER_LONG-16)))) {24 num -= 16;25 word <<= 16;26 }27 if (!(word & (~0ul << (BITS_PER_LONG-8)))) {28 num -= 8;29 word <<= 8;30 }31 if (!(word & (~0ul << (BITS_PER_LONG-4)))) {32 num -= 4;33 word <<= 4;34 }35 if (!(word & (~0ul << (BITS_PER_LONG-2)))) {36 num -= 2;37 word <<= 2;38 }39 if (!(word & (~0ul << (BITS_PER_LONG-1))))40 num -= 1;41 return num;42}43 44#ifndef __HAVE_ARCH___FLS45#define __fls(word) generic___fls(word)46#endif47 48#endif /* _ASM_GENERIC_BITOPS___FLS_H_ */49