Alexander Suvorov
32 lines
741 B
C++
32 lines
741 B
C++
// File: crn_hash.h
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// See Copyright Notice and license at the end of inc/crnlib.h
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#pragma once
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namespace crnlib {
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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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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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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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