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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_GENERIC_BITOPS___FFS_H_
#define _ASM_GENERIC_BITOPS___FFS_H_
#include <asm/types.h>
/**
* generic___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 generic___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;
}
#ifndef __HAVE_ARCH___FFS
#define __ffs(word) generic___ffs(word)
#endif
#endif /* _ASM_GENERIC_BITOPS___FFS_H_ */
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