You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
37 lines
860 B
37 lines
860 B
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_GENERIC_BITOPS_FLS64_H_
|
|
#define _ASM_GENERIC_BITOPS_FLS64_H_
|
|
|
|
#include <asm/types.h>
|
|
|
|
/**
|
|
* fls64 - find last set bit in a 64-bit word
|
|
* @x: the word to search
|
|
*
|
|
* This is defined in a similar way as the libc and compiler builtin
|
|
* ffsll, but returns the position of the most significant set bit.
|
|
*
|
|
* fls64(value) returns 0 if value is 0 or the position of the last
|
|
* set bit if value is nonzero. The last (most significant) bit is
|
|
* at position 64.
|
|
*/
|
|
#if BITS_PER_LONG == 32
|
|
static __always_inline int fls64(__u64 x)
|
|
{
|
|
__u32 h = x >> 32;
|
|
if (h)
|
|
return fls(h) + 32;
|
|
return fls(x);
|
|
}
|
|
#elif BITS_PER_LONG == 64
|
|
static __always_inline int fls64(__u64 x)
|
|
{
|
|
if (x == 0)
|
|
return 0;
|
|
return __fls(x) + 1;
|
|
}
|
|
#else
|
|
#error BITS_PER_LONG not 32 or 64
|
|
#endif
|
|
|
|
#endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */
|
|
|