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Rev 4065 Rev 5270
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static __always_inline u64 hash_64(u64 val, unsigned int bits)
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static __always_inline u64 hash_64(u64 val, unsigned int bits)
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{
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{
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	u64 hash = val;
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#if defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64
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	u64 hash = val;
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	hash = hash * GOLDEN_RATIO_PRIME_64;
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#else
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	/*  Sigh, gcc can't optimise this alone like it does for 32 bits. */
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	/*  Sigh, gcc can't optimise this alone like it does for 32 bits. */
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	u64 n = hash;
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	u64 n = hash;
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	n <<= 18;
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	n <<= 18;
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	hash -= n;
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	hash -= n;
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	n <<= 4;
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	n <<= 4;
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	hash += n;
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	hash += n;
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	n <<= 2;
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	n <<= 2;
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	hash += n;
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	hash += n;
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#endif
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	/* High bits are more random, so use them. */
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	/* High bits are more random, so use them. */
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	return hash >> (64 - bits);
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	return hash >> (64 - bits);
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#if BITS_PER_LONG == 64
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#if BITS_PER_LONG == 64
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	val ^= (val >> 32);
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	val ^= (val >> 32);
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#endif
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#endif
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	return (u32)val;
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	return (u32)val;
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}
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}
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#endif /* _LINUX_HASH_H */
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#endif /* _LINUX_HASH_H */