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diff --git a/tools/fuzzing/libfuzzer/FuzzerMutate.cpp b/tools/fuzzing/libfuzzer/FuzzerMutate.cpp
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+//===- FuzzerMutate.cpp - Mutate a test input -----------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+// Mutate a test input.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDefs.h"
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include "FuzzerMutate.h"
+#include "FuzzerOptions.h"
+#include "FuzzerTracePC.h"
+
+namespace fuzzer {
+
+const size_t Dictionary::kMaxDictSize;
+
+static void PrintASCII(const Word &W, const char *PrintAfter) {
+ PrintASCII(W.data(), W.size(), PrintAfter);
+}
+
+MutationDispatcher::MutationDispatcher(Random &Rand,
+ const FuzzingOptions &Options)
+ : Rand(Rand), Options(Options) {
+ DefaultMutators.insert(
+ DefaultMutators.begin(),
+ {
+ {&MutationDispatcher::Mutate_EraseBytes, "EraseBytes"},
+ {&MutationDispatcher::Mutate_InsertByte, "InsertByte"},
+ {&MutationDispatcher::Mutate_InsertRepeatedBytes,
+ "InsertRepeatedBytes"},
+ {&MutationDispatcher::Mutate_ChangeByte, "ChangeByte"},
+ {&MutationDispatcher::Mutate_ChangeBit, "ChangeBit"},
+ {&MutationDispatcher::Mutate_ShuffleBytes, "ShuffleBytes"},
+ {&MutationDispatcher::Mutate_ChangeASCIIInteger, "ChangeASCIIInt"},
+ {&MutationDispatcher::Mutate_ChangeBinaryInteger, "ChangeBinInt"},
+ {&MutationDispatcher::Mutate_CopyPart, "CopyPart"},
+ {&MutationDispatcher::Mutate_CrossOver, "CrossOver"},
+ {&MutationDispatcher::Mutate_AddWordFromManualDictionary,
+ "ManualDict"},
+ {&MutationDispatcher::Mutate_AddWordFromPersistentAutoDictionary,
+ "PersAutoDict"},
+ });
+ if(Options.UseCmp)
+ DefaultMutators.push_back(
+ {&MutationDispatcher::Mutate_AddWordFromTORC, "CMP"});
+
+ if (EF->LLVMFuzzerCustomMutator)
+ Mutators.push_back({&MutationDispatcher::Mutate_Custom, "Custom"});
+ else
+ Mutators = DefaultMutators;
+
+ if (EF->LLVMFuzzerCustomCrossOver)
+ Mutators.push_back(
+ {&MutationDispatcher::Mutate_CustomCrossOver, "CustomCrossOver"});
+}
+
+static char RandCh(Random &Rand) {
+ if (Rand.RandBool()) return Rand(256);
+ const char Special[] = "!*'();:@&=+$,/?%#[]012Az-`~.\xff\x00";
+ return Special[Rand(sizeof(Special) - 1)];
+}
+
+size_t MutationDispatcher::Mutate_Custom(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ return EF->LLVMFuzzerCustomMutator(Data, Size, MaxSize, Rand.Rand());
+}
+
+size_t MutationDispatcher::Mutate_CustomCrossOver(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size == 0)
+ return 0;
+ if (!CrossOverWith) return 0;
+ const Unit &Other = *CrossOverWith;
+ if (Other.empty())
+ return 0;
+ CustomCrossOverInPlaceHere.resize(MaxSize);
+ auto &U = CustomCrossOverInPlaceHere;
+ size_t NewSize = EF->LLVMFuzzerCustomCrossOver(
+ Data, Size, Other.data(), Other.size(), U.data(), U.size(), Rand.Rand());
+ if (!NewSize)
+ return 0;
+ assert(NewSize <= MaxSize && "CustomCrossOver returned overisized unit");
+ memcpy(Data, U.data(), NewSize);
+ return NewSize;
+}
+
+size_t MutationDispatcher::Mutate_ShuffleBytes(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize || Size == 0) return 0;
+ size_t ShuffleAmount =
+ Rand(std::min(Size, (size_t)8)) + 1; // [1,8] and <= Size.
+ size_t ShuffleStart = Rand(Size - ShuffleAmount);
+ assert(ShuffleStart + ShuffleAmount <= Size);
+ std::shuffle(Data + ShuffleStart, Data + ShuffleStart + ShuffleAmount, Rand);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_EraseBytes(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size <= 1) return 0;
+ size_t N = Rand(Size / 2) + 1;
+ assert(N < Size);
+ size_t Idx = Rand(Size - N + 1);
+ // Erase Data[Idx:Idx+N].
+ memmove(Data + Idx, Data + Idx + N, Size - Idx - N);
+ // Printf("Erase: %zd %zd => %zd; Idx %zd\n", N, Size, Size - N, Idx);
+ return Size - N;
+}
+
+size_t MutationDispatcher::Mutate_InsertByte(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size >= MaxSize) return 0;
+ size_t Idx = Rand(Size + 1);
+ // Insert new value at Data[Idx].
+ memmove(Data + Idx + 1, Data + Idx, Size - Idx);
+ Data[Idx] = RandCh(Rand);
+ return Size + 1;
+}
+
+size_t MutationDispatcher::Mutate_InsertRepeatedBytes(uint8_t *Data,
+ size_t Size,
+ size_t MaxSize) {
+ const size_t kMinBytesToInsert = 3;
+ if (Size + kMinBytesToInsert >= MaxSize) return 0;
+ size_t MaxBytesToInsert = std::min(MaxSize - Size, (size_t)128);
+ size_t N = Rand(MaxBytesToInsert - kMinBytesToInsert + 1) + kMinBytesToInsert;
+ assert(Size + N <= MaxSize && N);
+ size_t Idx = Rand(Size + 1);
+ // Insert new values at Data[Idx].
+ memmove(Data + Idx + N, Data + Idx, Size - Idx);
+ // Give preference to 0x00 and 0xff.
+ uint8_t Byte = Rand.RandBool() ? Rand(256) : (Rand.RandBool() ? 0 : 255);
+ for (size_t i = 0; i < N; i++)
+ Data[Idx + i] = Byte;
+ return Size + N;
+}
+
+size_t MutationDispatcher::Mutate_ChangeByte(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ size_t Idx = Rand(Size);
+ Data[Idx] = RandCh(Rand);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_ChangeBit(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ size_t Idx = Rand(Size);
+ Data[Idx] ^= 1 << Rand(8);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_AddWordFromManualDictionary(uint8_t *Data,
+ size_t Size,
+ size_t MaxSize) {
+ return AddWordFromDictionary(ManualDictionary, Data, Size, MaxSize);
+}
+
+size_t MutationDispatcher::ApplyDictionaryEntry(uint8_t *Data, size_t Size,
+ size_t MaxSize,
+ DictionaryEntry &DE) {
+ const Word &W = DE.GetW();
+ bool UsePositionHint = DE.HasPositionHint() &&
+ DE.GetPositionHint() + W.size() < Size &&
+ Rand.RandBool();
+ if (Rand.RandBool()) { // Insert W.
+ if (Size + W.size() > MaxSize) return 0;
+ size_t Idx = UsePositionHint ? DE.GetPositionHint() : Rand(Size + 1);
+ memmove(Data + Idx + W.size(), Data + Idx, Size - Idx);
+ memcpy(Data + Idx, W.data(), W.size());
+ Size += W.size();
+ } else { // Overwrite some bytes with W.
+ if (W.size() > Size) return 0;
+ size_t Idx = UsePositionHint ? DE.GetPositionHint() : Rand(Size - W.size());
+ memcpy(Data + Idx, W.data(), W.size());
+ }
+ return Size;
+}
+
+// Somewhere in the past we have observed a comparison instructions
+// with arguments Arg1 Arg2. This function tries to guess a dictionary
+// entry that will satisfy that comparison.
+// It first tries to find one of the arguments (possibly swapped) in the
+// input and if it succeeds it creates a DE with a position hint.
+// Otherwise it creates a DE with one of the arguments w/o a position hint.
+DictionaryEntry MutationDispatcher::MakeDictionaryEntryFromCMP(
+ const void *Arg1, const void *Arg2,
+ const void *Arg1Mutation, const void *Arg2Mutation,
+ size_t ArgSize, const uint8_t *Data,
+ size_t Size) {
+ bool HandleFirst = Rand.RandBool();
+ const void *ExistingBytes, *DesiredBytes;
+ Word W;
+ const uint8_t *End = Data + Size;
+ for (int Arg = 0; Arg < 2; Arg++) {
+ ExistingBytes = HandleFirst ? Arg1 : Arg2;
+ DesiredBytes = HandleFirst ? Arg2Mutation : Arg1Mutation;
+ HandleFirst = !HandleFirst;
+ W.Set(reinterpret_cast<const uint8_t*>(DesiredBytes), ArgSize);
+ const size_t kMaxNumPositions = 8;
+ size_t Positions[kMaxNumPositions];
+ size_t NumPositions = 0;
+ for (const uint8_t *Cur = Data;
+ Cur < End && NumPositions < kMaxNumPositions; Cur++) {
+ Cur =
+ (const uint8_t *)SearchMemory(Cur, End - Cur, ExistingBytes, ArgSize);
+ if (!Cur) break;
+ Positions[NumPositions++] = Cur - Data;
+ }
+ if (!NumPositions) continue;
+ return DictionaryEntry(W, Positions[Rand(NumPositions)]);
+ }
+ DictionaryEntry DE(W);
+ return DE;
+}
+
+
+template <class T>
+DictionaryEntry MutationDispatcher::MakeDictionaryEntryFromCMP(
+ T Arg1, T Arg2, const uint8_t *Data, size_t Size) {
+ if (Rand.RandBool()) Arg1 = Bswap(Arg1);
+ if (Rand.RandBool()) Arg2 = Bswap(Arg2);
+ T Arg1Mutation = Arg1 + Rand(-1, 1);
+ T Arg2Mutation = Arg2 + Rand(-1, 1);
+ return MakeDictionaryEntryFromCMP(&Arg1, &Arg2, &Arg1Mutation, &Arg2Mutation,
+ sizeof(Arg1), Data, Size);
+}
+
+DictionaryEntry MutationDispatcher::MakeDictionaryEntryFromCMP(
+ const Word &Arg1, const Word &Arg2, const uint8_t *Data, size_t Size) {
+ return MakeDictionaryEntryFromCMP(Arg1.data(), Arg2.data(), Arg1.data(),
+ Arg2.data(), Arg1.size(), Data, Size);
+}
+
+size_t MutationDispatcher::Mutate_AddWordFromTORC(
+ uint8_t *Data, size_t Size, size_t MaxSize) {
+ Word W;
+ DictionaryEntry DE;
+ switch (Rand(4)) {
+ case 0: {
+ auto X = TPC.TORC8.Get(Rand.Rand());
+ DE = MakeDictionaryEntryFromCMP(X.A, X.B, Data, Size);
+ } break;
+ case 1: {
+ auto X = TPC.TORC4.Get(Rand.Rand());
+ if ((X.A >> 16) == 0 && (X.B >> 16) == 0 && Rand.RandBool())
+ DE = MakeDictionaryEntryFromCMP((uint16_t)X.A, (uint16_t)X.B, Data, Size);
+ else
+ DE = MakeDictionaryEntryFromCMP(X.A, X.B, Data, Size);
+ } break;
+ case 2: {
+ auto X = TPC.TORCW.Get(Rand.Rand());
+ DE = MakeDictionaryEntryFromCMP(X.A, X.B, Data, Size);
+ } break;
+ case 3: if (Options.UseMemmem) {
+ auto X = TPC.MMT.Get(Rand.Rand());
+ DE = DictionaryEntry(X);
+ } break;
+ default:
+ assert(0);
+ }
+ if (!DE.GetW().size()) return 0;
+ Size = ApplyDictionaryEntry(Data, Size, MaxSize, DE);
+ if (!Size) return 0;
+ DictionaryEntry &DERef =
+ CmpDictionaryEntriesDeque[CmpDictionaryEntriesDequeIdx++ %
+ kCmpDictionaryEntriesDequeSize];
+ DERef = DE;
+ CurrentDictionaryEntrySequence.push_back(&DERef);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_AddWordFromPersistentAutoDictionary(
+ uint8_t *Data, size_t Size, size_t MaxSize) {
+ return AddWordFromDictionary(PersistentAutoDictionary, Data, Size, MaxSize);
+}
+
+size_t MutationDispatcher::AddWordFromDictionary(Dictionary &D, uint8_t *Data,
+ size_t Size, size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ if (D.empty()) return 0;
+ DictionaryEntry &DE = D[Rand(D.size())];
+ Size = ApplyDictionaryEntry(Data, Size, MaxSize, DE);
+ if (!Size) return 0;
+ DE.IncUseCount();
+ CurrentDictionaryEntrySequence.push_back(&DE);
+ return Size;
+}
+
+// Overwrites part of To[0,ToSize) with a part of From[0,FromSize).
+// Returns ToSize.
+size_t MutationDispatcher::CopyPartOf(const uint8_t *From, size_t FromSize,
+ uint8_t *To, size_t ToSize) {
+ // Copy From[FromBeg, FromBeg + CopySize) into To[ToBeg, ToBeg + CopySize).
+ size_t ToBeg = Rand(ToSize);
+ size_t CopySize = Rand(ToSize - ToBeg) + 1;
+ assert(ToBeg + CopySize <= ToSize);
+ CopySize = std::min(CopySize, FromSize);
+ size_t FromBeg = Rand(FromSize - CopySize + 1);
+ assert(FromBeg + CopySize <= FromSize);
+ memmove(To + ToBeg, From + FromBeg, CopySize);
+ return ToSize;
+}
+
+// Inserts part of From[0,ToSize) into To.
+// Returns new size of To on success or 0 on failure.
+size_t MutationDispatcher::InsertPartOf(const uint8_t *From, size_t FromSize,
+ uint8_t *To, size_t ToSize,
+ size_t MaxToSize) {
+ if (ToSize >= MaxToSize) return 0;
+ size_t AvailableSpace = MaxToSize - ToSize;
+ size_t MaxCopySize = std::min(AvailableSpace, FromSize);
+ size_t CopySize = Rand(MaxCopySize) + 1;
+ size_t FromBeg = Rand(FromSize - CopySize + 1);
+ assert(FromBeg + CopySize <= FromSize);
+ size_t ToInsertPos = Rand(ToSize + 1);
+ assert(ToInsertPos + CopySize <= MaxToSize);
+ size_t TailSize = ToSize - ToInsertPos;
+ if (To == From) {
+ MutateInPlaceHere.resize(MaxToSize);
+ memcpy(MutateInPlaceHere.data(), From + FromBeg, CopySize);
+ memmove(To + ToInsertPos + CopySize, To + ToInsertPos, TailSize);
+ memmove(To + ToInsertPos, MutateInPlaceHere.data(), CopySize);
+ } else {
+ memmove(To + ToInsertPos + CopySize, To + ToInsertPos, TailSize);
+ memmove(To + ToInsertPos, From + FromBeg, CopySize);
+ }
+ return ToSize + CopySize;
+}
+
+size_t MutationDispatcher::Mutate_CopyPart(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize || Size == 0) return 0;
+ // If Size == MaxSize, `InsertPartOf(...)` will
+ // fail so there's no point using it in this case.
+ if (Size == MaxSize || Rand.RandBool())
+ return CopyPartOf(Data, Size, Data, Size);
+ else
+ return InsertPartOf(Data, Size, Data, Size, MaxSize);
+}
+
+size_t MutationDispatcher::Mutate_ChangeASCIIInteger(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ size_t B = Rand(Size);
+ while (B < Size && !isdigit(Data[B])) B++;
+ if (B == Size) return 0;
+ size_t E = B;
+ while (E < Size && isdigit(Data[E])) E++;
+ assert(B < E);
+ // now we have digits in [B, E).
+ // strtol and friends don't accept non-zero-teminated data, parse it manually.
+ uint64_t Val = Data[B] - '0';
+ for (size_t i = B + 1; i < E; i++)
+ Val = Val * 10 + Data[i] - '0';
+
+ // Mutate the integer value.
+ switch(Rand(5)) {
+ case 0: Val++; break;
+ case 1: Val--; break;
+ case 2: Val /= 2; break;
+ case 3: Val *= 2; break;
+ case 4: Val = Rand(Val * Val); break;
+ default: assert(0);
+ }
+ // Just replace the bytes with the new ones, don't bother moving bytes.
+ for (size_t i = B; i < E; i++) {
+ size_t Idx = E + B - i - 1;
+ assert(Idx >= B && Idx < E);
+ Data[Idx] = (Val % 10) + '0';
+ Val /= 10;
+ }
+ return Size;
+}
+
+template<class T>
+size_t ChangeBinaryInteger(uint8_t *Data, size_t Size, Random &Rand) {
+ if (Size < sizeof(T)) return 0;
+ size_t Off = Rand(Size - sizeof(T) + 1);
+ assert(Off + sizeof(T) <= Size);
+ T Val;
+ if (Off < 64 && !Rand(4)) {
+ Val = Size;
+ if (Rand.RandBool())
+ Val = Bswap(Val);
+ } else {
+ memcpy(&Val, Data + Off, sizeof(Val));
+ T Add = Rand(21);
+ Add -= 10;
+ if (Rand.RandBool())
+ Val = Bswap(T(Bswap(Val) + Add)); // Add assuming different endiannes.
+ else
+ Val = Val + Add; // Add assuming current endiannes.
+ if (Add == 0 || Rand.RandBool()) // Maybe negate.
+ Val = -Val;
+ }
+ memcpy(Data + Off, &Val, sizeof(Val));
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_ChangeBinaryInteger(uint8_t *Data,
+ size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ switch (Rand(4)) {
+ case 3: return ChangeBinaryInteger<uint64_t>(Data, Size, Rand);
+ case 2: return ChangeBinaryInteger<uint32_t>(Data, Size, Rand);
+ case 1: return ChangeBinaryInteger<uint16_t>(Data, Size, Rand);
+ case 0: return ChangeBinaryInteger<uint8_t>(Data, Size, Rand);
+ default: assert(0);
+ }
+ return 0;
+}
+
+size_t MutationDispatcher::Mutate_CrossOver(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ if (Size == 0) return 0;
+ if (!CrossOverWith) return 0;
+ const Unit &O = *CrossOverWith;
+ if (O.empty()) return 0;
+ MutateInPlaceHere.resize(MaxSize);
+ auto &U = MutateInPlaceHere;
+ size_t NewSize = 0;
+ switch(Rand(3)) {
+ case 0:
+ NewSize = CrossOver(Data, Size, O.data(), O.size(), U.data(), U.size());
+ break;
+ case 1:
+ NewSize = InsertPartOf(O.data(), O.size(), U.data(), U.size(), MaxSize);
+ if (!NewSize)
+ NewSize = CopyPartOf(O.data(), O.size(), U.data(), U.size());
+ break;
+ case 2:
+ NewSize = CopyPartOf(O.data(), O.size(), U.data(), U.size());
+ break;
+ default: assert(0);
+ }
+ assert(NewSize > 0 && "CrossOver returned empty unit");
+ assert(NewSize <= MaxSize && "CrossOver returned overisized unit");
+ memcpy(Data, U.data(), NewSize);
+ return NewSize;
+}
+
+void MutationDispatcher::StartMutationSequence() {
+ CurrentMutatorSequence.clear();
+ CurrentDictionaryEntrySequence.clear();
+}
+
+// Copy successful dictionary entries to PersistentAutoDictionary.
+void MutationDispatcher::RecordSuccessfulMutationSequence() {
+ for (auto DE : CurrentDictionaryEntrySequence) {
+ // PersistentAutoDictionary.AddWithSuccessCountOne(DE);
+ DE->IncSuccessCount();
+ assert(DE->GetW().size());
+ // Linear search is fine here as this happens seldom.
+ if (!PersistentAutoDictionary.ContainsWord(DE->GetW()))
+ PersistentAutoDictionary.push_back({DE->GetW(), 1});
+ }
+}
+
+void MutationDispatcher::PrintRecommendedDictionary() {
+ Vector<DictionaryEntry> V;
+ for (auto &DE : PersistentAutoDictionary)
+ if (!ManualDictionary.ContainsWord(DE.GetW()))
+ V.push_back(DE);
+ if (V.empty()) return;
+ Printf("###### Recommended dictionary. ######\n");
+ for (auto &DE: V) {
+ assert(DE.GetW().size());
+ Printf("\"");
+ PrintASCII(DE.GetW(), "\"");
+ Printf(" # Uses: %zd\n", DE.GetUseCount());
+ }
+ Printf("###### End of recommended dictionary. ######\n");
+}
+
+void MutationDispatcher::PrintMutationSequence() {
+ Printf("MS: %zd ", CurrentMutatorSequence.size());
+ for (auto M : CurrentMutatorSequence)
+ Printf("%s-", M.Name);
+ if (!CurrentDictionaryEntrySequence.empty()) {
+ Printf(" DE: ");
+ for (auto DE : CurrentDictionaryEntrySequence) {
+ Printf("\"");
+ PrintASCII(DE->GetW(), "\"-");
+ }
+ }
+}
+
+size_t MutationDispatcher::Mutate(uint8_t *Data, size_t Size, size_t MaxSize) {
+ return MutateImpl(Data, Size, MaxSize, Mutators);
+}
+
+size_t MutationDispatcher::DefaultMutate(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ return MutateImpl(Data, Size, MaxSize, DefaultMutators);
+}
+
+// Mutates Data in place, returns new size.
+size_t MutationDispatcher::MutateImpl(uint8_t *Data, size_t Size,
+ size_t MaxSize,
+ Vector<Mutator> &Mutators) {
+ assert(MaxSize > 0);
+ // Some mutations may fail (e.g. can't insert more bytes if Size == MaxSize),
+ // in which case they will return 0.
+ // Try several times before returning un-mutated data.
+ for (int Iter = 0; Iter < 100; Iter++) {
+ auto M = Mutators[Rand(Mutators.size())];
+ size_t NewSize = (this->*(M.Fn))(Data, Size, MaxSize);
+ if (NewSize && NewSize <= MaxSize) {
+ if (Options.OnlyASCII)
+ ToASCII(Data, NewSize);
+ CurrentMutatorSequence.push_back(M);
+ return NewSize;
+ }
+ }
+ *Data = ' ';
+ return 1; // Fallback, should not happen frequently.
+}
+
+// Mask represents the set of Data bytes that are worth mutating.
+size_t MutationDispatcher::MutateWithMask(uint8_t *Data, size_t Size,
+ size_t MaxSize,
+ const Vector<uint8_t> &Mask) {
+ size_t MaskedSize = std::min(Size, Mask.size());
+ // * Copy the worthy bytes into a temporary array T
+ // * Mutate T
+ // * Copy T back.
+ // This is totally unoptimized.
+ auto &T = MutateWithMaskTemp;
+ if (T.size() < Size)
+ T.resize(Size);
+ size_t OneBits = 0;
+ for (size_t I = 0; I < MaskedSize; I++)
+ if (Mask[I])
+ T[OneBits++] = Data[I];
+
+ if (!OneBits) return 0;
+ assert(!T.empty());
+ size_t NewSize = Mutate(T.data(), OneBits, OneBits);
+ assert(NewSize <= OneBits);
+ (void)NewSize;
+ // Even if NewSize < OneBits we still use all OneBits bytes.
+ for (size_t I = 0, J = 0; I < MaskedSize; I++)
+ if (Mask[I])
+ Data[I] = T[J++];
+ return Size;
+}
+
+void MutationDispatcher::AddWordToManualDictionary(const Word &W) {
+ ManualDictionary.push_back(
+ {W, std::numeric_limits<size_t>::max()});
+}
+
+} // namespace fuzzer