73 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			73 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C++
		
	
	
	
//===- FuzzerValueBitMap.h - INTERNAL - Bit map -----------------*- 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
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
// ValueBitMap.
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
#ifndef LLVM_FUZZER_VALUE_BIT_MAP_H
 | 
						|
#define LLVM_FUZZER_VALUE_BIT_MAP_H
 | 
						|
 | 
						|
#include "FuzzerDefs.h"
 | 
						|
 | 
						|
namespace fuzzer {
 | 
						|
 | 
						|
// A bit map containing kMapSizeInWords bits.
 | 
						|
struct ValueBitMap {
 | 
						|
  static const size_t kMapSizeInBits = 1 << 16;
 | 
						|
  static const size_t kMapPrimeMod = 65371;  // Largest Prime < kMapSizeInBits;
 | 
						|
  static const size_t kBitsInWord = (sizeof(uintptr_t) * 8);
 | 
						|
  static const size_t kMapSizeInWords = kMapSizeInBits / kBitsInWord;
 | 
						|
 public:
 | 
						|
 | 
						|
  // Clears all bits.
 | 
						|
  void Reset() { memset(Map, 0, sizeof(Map)); }
 | 
						|
 | 
						|
  // Computes a hash function of Value and sets the corresponding bit.
 | 
						|
  // Returns true if the bit was changed from 0 to 1.
 | 
						|
  ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
  inline bool AddValue(uintptr_t Value) {
 | 
						|
    uintptr_t Idx = Value % kMapSizeInBits;
 | 
						|
    uintptr_t WordIdx = Idx / kBitsInWord;
 | 
						|
    uintptr_t BitIdx = Idx % kBitsInWord;
 | 
						|
    uintptr_t Old = Map[WordIdx];
 | 
						|
    uintptr_t New = Old | (1ULL << BitIdx);
 | 
						|
    Map[WordIdx] = New;
 | 
						|
    return New != Old;
 | 
						|
  }
 | 
						|
 | 
						|
  ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
  inline bool AddValueModPrime(uintptr_t Value) {
 | 
						|
    return AddValue(Value % kMapPrimeMod);
 | 
						|
  }
 | 
						|
 | 
						|
  inline bool Get(uintptr_t Idx) {
 | 
						|
    assert(Idx < kMapSizeInBits);
 | 
						|
    uintptr_t WordIdx = Idx / kBitsInWord;
 | 
						|
    uintptr_t BitIdx = Idx % kBitsInWord;
 | 
						|
    return Map[WordIdx] & (1ULL << BitIdx);
 | 
						|
  }
 | 
						|
 | 
						|
  size_t SizeInBits() const { return kMapSizeInBits; }
 | 
						|
 | 
						|
  template <class Callback>
 | 
						|
  ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
  void ForEach(Callback CB) const {
 | 
						|
    for (size_t i = 0; i < kMapSizeInWords; i++)
 | 
						|
      if (uintptr_t M = Map[i])
 | 
						|
        for (size_t j = 0; j < sizeof(M) * 8; j++)
 | 
						|
          if (M & ((uintptr_t)1 << j))
 | 
						|
            CB(i * sizeof(M) * 8 + j);
 | 
						|
  }
 | 
						|
 | 
						|
 private:
 | 
						|
  ATTRIBUTE_ALIGNED(512) uintptr_t Map[kMapSizeInWords];
 | 
						|
};
 | 
						|
 | 
						|
}  // namespace fuzzer
 | 
						|
 | 
						|
#endif  // LLVM_FUZZER_VALUE_BIT_MAP_H
 |