| 1 |
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| 2 | #ifndef _ASM_GENERIC_BITOPS_FLS64_H_
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| 3 | #define _ASM_GENERIC_BITOPS_FLS64_H_
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| 4 |
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| 5 | #include <asm/types.h>
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| 6 |
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| 7 | |
| 8 | * fls64 - find last set bit in a 64-bit word
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| 9 | * @x: the word to search
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| 10 | *
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| 11 | * This is defined in a similar way as the libc and compiler builtin
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| 12 | * ffsll, but returns the position of the most significant set bit.
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| 13 | *
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| 14 | * fls64(value) returns 0 if value is 0 or the position of the last
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| 15 | * set bit if value is nonzero. The last (most significant) bit is
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| 16 | * at position 64.
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| 17 |
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| 18 | #if BITS_PER_LONG == 32
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| 19 | static __always_inline __attribute_const__ int fls64(__u64 x)
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| 20 | {
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| 21 | __u32 h = x >> 32;
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| 22 | if (h)
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| 23 | return fls(h) + 32;
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| 24 | return fls(x);
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| 25 | }
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| 26 | #elif BITS_PER_LONG == 64
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| 27 | static __always_inline __attribute_const__ int fls64(__u64 x)
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| 28 | {
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| 29 | if (x == 0)
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| 30 | return 0;
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| 31 | return __fls(x) + 1;
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| 32 | }
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| 33 | #else
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| 34 | #error BITS_PER_LONG not 32 or 64
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| 35 | #endif
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| 36 |
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| 37 | #endif
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