1326943Sdim//===- FuzzerValueBitMap.h - INTERNAL - Bit map -----------------*- C++ -* ===// 2326943Sdim// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6326943Sdim// 7326943Sdim//===----------------------------------------------------------------------===// 8326943Sdim// ValueBitMap. 9326943Sdim//===----------------------------------------------------------------------===// 10326943Sdim 11326943Sdim#ifndef LLVM_FUZZER_VALUE_BIT_MAP_H 12326943Sdim#define LLVM_FUZZER_VALUE_BIT_MAP_H 13326943Sdim 14326943Sdim#include "FuzzerDefs.h" 15326943Sdim 16326943Sdimnamespace fuzzer { 17326943Sdim 18326943Sdim// A bit map containing kMapSizeInWords bits. 19326943Sdimstruct ValueBitMap { 20326943Sdim static const size_t kMapSizeInBits = 1 << 16; 21326943Sdim static const size_t kMapPrimeMod = 65371; // Largest Prime < kMapSizeInBits; 22326943Sdim static const size_t kBitsInWord = (sizeof(uintptr_t) * 8); 23326943Sdim static const size_t kMapSizeInWords = kMapSizeInBits / kBitsInWord; 24326943Sdim public: 25326943Sdim 26326943Sdim // Clears all bits. 27326943Sdim void Reset() { memset(Map, 0, sizeof(Map)); } 28326943Sdim 29326943Sdim // Computes a hash function of Value and sets the corresponding bit. 30326943Sdim // Returns true if the bit was changed from 0 to 1. 31326943Sdim ATTRIBUTE_NO_SANITIZE_ALL 32326943Sdim inline bool AddValue(uintptr_t Value) { 33326943Sdim uintptr_t Idx = Value % kMapSizeInBits; 34326943Sdim uintptr_t WordIdx = Idx / kBitsInWord; 35326943Sdim uintptr_t BitIdx = Idx % kBitsInWord; 36326943Sdim uintptr_t Old = Map[WordIdx]; 37353358Sdim uintptr_t New = Old | (1ULL << BitIdx); 38326943Sdim Map[WordIdx] = New; 39326943Sdim return New != Old; 40326943Sdim } 41326943Sdim 42326943Sdim ATTRIBUTE_NO_SANITIZE_ALL 43326943Sdim inline bool AddValueModPrime(uintptr_t Value) { 44326943Sdim return AddValue(Value % kMapPrimeMod); 45326943Sdim } 46326943Sdim 47326943Sdim inline bool Get(uintptr_t Idx) { 48326943Sdim assert(Idx < kMapSizeInBits); 49326943Sdim uintptr_t WordIdx = Idx / kBitsInWord; 50326943Sdim uintptr_t BitIdx = Idx % kBitsInWord; 51353358Sdim return Map[WordIdx] & (1ULL << BitIdx); 52326943Sdim } 53326943Sdim 54326943Sdim size_t SizeInBits() const { return kMapSizeInBits; } 55326943Sdim 56326943Sdim template <class Callback> 57326943Sdim ATTRIBUTE_NO_SANITIZE_ALL 58326943Sdim void ForEach(Callback CB) const { 59326943Sdim for (size_t i = 0; i < kMapSizeInWords; i++) 60326943Sdim if (uintptr_t M = Map[i]) 61326943Sdim for (size_t j = 0; j < sizeof(M) * 8; j++) 62326943Sdim if (M & ((uintptr_t)1 << j)) 63326943Sdim CB(i * sizeof(M) * 8 + j); 64326943Sdim } 65326943Sdim 66326943Sdim private: 67353358Sdim ATTRIBUTE_ALIGNED(512) uintptr_t Map[kMapSizeInWords]; 68326943Sdim}; 69326943Sdim 70326943Sdim} // namespace fuzzer 71326943Sdim 72326943Sdim#endif // LLVM_FUZZER_VALUE_BIT_MAP_H 73