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/* SPDX-License-Identifier: GPL-2.0 */#ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_#define _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_ #include <asm/types.h>#include <asm/bitsperlong.h> /** * __ffs - find first bit in word. * @word: The word to search * * Undefined if no bit exists, so code should check against 0 first. */static __always_inline unsigned int __ffs(unsigned long word){	unsigned int num = 0; #if __BITS_PER_LONG == 64	if ((word & 0xffffffff) == 0) {		num += 32;		word >>= 32;	}#endif	if ((word & 0xffff) == 0) {		num += 16;		word >>= 16;	}	if ((word & 0xff) == 0) {		num += 8;		word >>= 8;	}	if ((word & 0xf) == 0) {		num += 4;		word >>= 4;	}	if ((word & 0x3) == 0) {		num += 2;		word >>= 2;	}	if ((word & 0x1) == 0)		num += 1;	return num;} #endif /* _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_ */