diff options
Diffstat (limited to 'json4cpp/tests/thirdparty/Fuzzer/FuzzerValueBitMap.h')
| -rw-r--r-- | json4cpp/tests/thirdparty/Fuzzer/FuzzerValueBitMap.h | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/json4cpp/tests/thirdparty/Fuzzer/FuzzerValueBitMap.h b/json4cpp/tests/thirdparty/Fuzzer/FuzzerValueBitMap.h new file mode 100644 index 0000000000..0692acd13e --- /dev/null +++ b/json4cpp/tests/thirdparty/Fuzzer/FuzzerValueBitMap.h @@ -0,0 +1,87 @@ +//===- FuzzerValueBitMap.h - INTERNAL - Bit map -----------------*- C++ -* ===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// 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 = 65371; // Prime. + static const size_t kMapSizeInBitsAligned = 65536; // 2^16 + static const size_t kBitsInWord = (sizeof(uintptr_t) * 8); + static const size_t kMapSizeInWords = kMapSizeInBitsAligned / kBitsInWord; + public: + static const size_t kNumberOfItems = kMapSizeInBits; + // 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. + inline bool AddValue(uintptr_t Value) { + uintptr_t Idx = Value < kMapSizeInBits ? Value : Value % kMapSizeInBits; + uintptr_t WordIdx = Idx / kBitsInWord; + uintptr_t BitIdx = Idx % kBitsInWord; + uintptr_t Old = Map[WordIdx]; + uintptr_t New = Old | (1UL << BitIdx); + Map[WordIdx] = New; + return New != Old; + } + + inline bool Get(uintptr_t Idx) { + assert(Idx < kMapSizeInBits); + uintptr_t WordIdx = Idx / kBitsInWord; + uintptr_t BitIdx = Idx % kBitsInWord; + return Map[WordIdx] & (1UL << BitIdx); + } + + size_t GetNumBitsSinceLastMerge() const { return NumBits; } + + // Merges 'Other' into 'this', clears 'Other', updates NumBits, + // returns true if new bits were added. + ATTRIBUTE_TARGET_POPCNT + bool MergeFrom(ValueBitMap &Other) { + uintptr_t Res = 0; + size_t OldNumBits = NumBits; + for (size_t i = 0; i < kMapSizeInWords; i++) { + auto O = Other.Map[i]; + auto M = Map[i]; + if (O) { + Map[i] = (M |= O); + Other.Map[i] = 0; + } + if (M) + Res += __builtin_popcountl(M); + } + NumBits = Res; + return OldNumBits < NumBits; + } + + template <class Callback> + void ForEach(Callback CB) { + 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: + size_t NumBits = 0; + uintptr_t Map[kMapSizeInWords] __attribute__((aligned(512))); +}; + +} // namespace fuzzer + +#endif // LLVM_FUZZER_VALUE_BIT_MAP_H |
