diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-10-20 00:10:27 -0300 |
---|---|---|
committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-10-20 00:10:27 -0300 |
commit | d0b2f91bede3bd5e3d24dd6803e56eee959c1797 (patch) | |
tree | 7fee4ab0509879c373c4f2cbd5b8a5be5b4041ee /tools/include/asm-generic/bitops/fls64.h | |
parent | e914f8eb445e8f74b00303c19c2ffceaedd16a05 (diff) |
Linux-libre 4.8.2-gnupck-4.8.2-gnu
Diffstat (limited to 'tools/include/asm-generic/bitops/fls64.h')
-rw-r--r-- | tools/include/asm-generic/bitops/fls64.h | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/tools/include/asm-generic/bitops/fls64.h b/tools/include/asm-generic/bitops/fls64.h index 35bee0071..b097cf844 100644 --- a/tools/include/asm-generic/bitops/fls64.h +++ b/tools/include/asm-generic/bitops/fls64.h @@ -1 +1,36 @@ -#include "../../../../include/asm-generic/bitops/fls64.h" +#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_ */ |