1 //===-- sanitizer_common.h --------------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file implements a simple hash function. 10 //===----------------------------------------------------------------------===// 11 12 #ifndef SANITIZER_HASH_H 13 #define SANITIZER_HASH_H 14 15 #include "sanitizer_internal_defs.h" 16 17 namespace __sanitizer { 18 class MurMur2HashBuilder { 19 static const u32 m = 0x5bd1e995; 20 static const u32 seed = 0x9747b28c; 21 static const u32 r = 24; 22 u32 h; 23 24 public: 25 explicit MurMur2HashBuilder(u32 init = 0) { h = seed ^ init; } 26 void add(u32 k) { 27 k *= m; 28 k ^= k >> r; 29 k *= m; 30 h *= m; 31 h ^= k; 32 } 33 u32 get() { 34 u32 x = h; 35 x ^= x >> 13; 36 x *= m; 37 x ^= x >> 15; 38 return x; 39 } 40 }; 41 } //namespace __sanitizer 42 43 #endif // SANITIZER_HASH_H 44