richgel999
35 lines
809 B
C++
35 lines
809 B
C++
// File: crn_hash.h
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// This software is in the public domain. Please see license.txt.
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#pragma once
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namespace crnlib
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{
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uint32 fast_hash (const void* p, int len);
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// 4-byte integer hash, full avalanche
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inline uint32 bitmix32c(uint32 a)
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{
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a = (a+0x7ed55d16) + (a<<12);
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a = (a^0xc761c23c) ^ (a>>19);
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a = (a+0x165667b1) + (a<<5);
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a = (a+0xd3a2646c) ^ (a<<9);
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a = (a+0xfd7046c5) + (a<<3);
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a = (a^0xb55a4f09) ^ (a>>16);
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return a;
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}
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// 4-byte integer hash, full avalanche, no constants
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inline uint32 bitmix32(uint32 a)
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{
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a -= (a<<6);
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a ^= (a>>17);
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a -= (a<<9);
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a ^= (a<<4);
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a -= (a<<3);
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a ^= (a<<10);
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a ^= (a>>15);
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return a;
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}
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} // namespace crnlib
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