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1 //===-- sanitizer_common.h --------------------------------------*- C++ -*-===//
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2 //
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3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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4 // See https://llvm.org/LICENSE.txt for license information.
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5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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6 //
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7 //===----------------------------------------------------------------------===//
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8 //
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9 // This file implements a simple hash function.
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10 //===----------------------------------------------------------------------===//
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11
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12 #ifndef SANITIZER_HASH_H
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13 #define SANITIZER_HASH_H
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14
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15 #include "sanitizer_internal_defs.h"
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16
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17 namespace __sanitizer {
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18 class MurMur2HashBuilder {
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19 static const u32 m = 0x5bd1e995;
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20 static const u32 seed = 0x9747b28c;
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21 static const u32 r = 24;
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22 u32 h;
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23
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24 public:
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25 explicit MurMur2HashBuilder(u32 init = 0) { h = seed ^ init; }
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26 void add(u32 k) {
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27 k *= m;
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28 k ^= k >> r;
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29 k *= m;
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30 h *= m;
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31 h ^= k;
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32 }
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33 u32 get() {
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34 u32 x = h;
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35 x ^= x >> 13;
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36 x *= m;
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37 x ^= x >> 15;
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38 return x;
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39 }
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40 };
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41 } //namespace __sanitizer
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42
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43 #endif // SANITIZER_HASH_H
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