Projet_SETI_RISC-V/riscv-gnu-toolchain/gcc/libsanitizer/sanitizer_common/sanitizer_hash.h
2023-03-06 14:48:14 +01:00

67 lines
1.5 KiB
C++

//===-- sanitizer_common.h --------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements a simple hash function.
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_HASH_H
#define SANITIZER_HASH_H
#include "sanitizer_internal_defs.h"
namespace __sanitizer {
class MurMur2HashBuilder {
static const u32 m = 0x5bd1e995;
static const u32 seed = 0x9747b28c;
static const u32 r = 24;
u32 h;
public:
explicit MurMur2HashBuilder(u32 init = 0) { h = seed ^ init; }
void add(u32 k) {
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
}
u32 get() {
u32 x = h;
x ^= x >> 13;
x *= m;
x ^= x >> 15;
return x;
}
};
class MurMur2Hash64Builder {
static const u64 m = 0xc6a4a7935bd1e995ull;
static const u64 seed = 0x9747b28c9747b28cull;
static const u64 r = 47;
u64 h;
public:
explicit MurMur2Hash64Builder(u64 init = 0) { h = seed ^ (init * m); }
void add(u64 k) {
k *= m;
k ^= k >> r;
k *= m;
h ^= k;
h *= m;
}
u64 get() {
u64 x = h;
x ^= x >> r;
x *= m;
x ^= x >> r;
return x;
}
};
} //namespace __sanitizer
#endif // SANITIZER_HASH_H