[libFuzzer] refactor the mutation functions so that they are now methods of a class. NFC

llvm-svn: 246808

llvm/lib/Fuzzer/FuzzerCrossOver.cpp

@@ -16,9 +16,9 @@
 namespace fuzzer {
 
 // Cross Data1 and Data2, store the result (up to MaxOutSize bytes) in Out.
-size_t CrossOver(const uint8_t *Data1, size_t Size1,
+size_t MutationDispatcher::CrossOver(const uint8_t *Data1, size_t Size1,
-                 const uint8_t *Data2, size_t Size2,
+                                     const uint8_t *Data2, size_t Size2,
-                 uint8_t *Out, size_t MaxOutSize, FuzzerRandomBase &Rand) {
+                                     uint8_t *Out, size_t MaxOutSize) {
   assert(Size1 || Size2);
   MaxOutSize = Rand(MaxOutSize) + 1;
   size_t OutPos = 0;

llvm/lib/Fuzzer/FuzzerInterface.cpp

@@ -20,9 +20,10 @@ void FuzzerRandomLibc::ResetSeed(int seed) { srand(seed); }
 size_t FuzzerRandomLibc::Rand() { return rand(); }
 
 UserSuppliedFuzzer::UserSuppliedFuzzer()
-    : OwnRand(true), Rand(new FuzzerRandomLibc(0)) {}
+    : OwnRand(true), Rand(new FuzzerRandomLibc(0)), MD(*Rand) {}
 
-UserSuppliedFuzzer::UserSuppliedFuzzer(FuzzerRandomBase *Rand) : Rand(Rand) {}
+UserSuppliedFuzzer::UserSuppliedFuzzer(FuzzerRandomBase *Rand)
+    : Rand(Rand), MD(*Rand) {}
 
 UserSuppliedFuzzer::~UserSuppliedFuzzer() {
   if (OwnRand)

llvm/lib/Fuzzer/FuzzerInterface.h

@@ -62,33 +62,38 @@ class FuzzerRandomLibc : public FuzzerRandomBase {
   size_t Rand() override;
 };
 
+class MutationDispatcher {
+ public:
+  MutationDispatcher(FuzzerRandomBase &Rand) : Rand(Rand) {}
+  /// Mutates data by shuffling bytes.
+  size_t Mutate_ShuffleBytes(uint8_t *Data, size_t Size, size_t MaxSize);
+  /// Mutates data by erasing a byte.
+  size_t Mutate_EraseByte(uint8_t *Data, size_t Size, size_t MaxSize);
+  /// Mutates data by inserting a byte.
+  size_t Mutate_InsertByte(uint8_t *Data, size_t Size, size_t MaxSize);
+  /// Mutates data by chanding one byte.
+  size_t Mutate_ChangeByte(uint8_t *Data, size_t Size, size_t MaxSize);
+  /// Mutates data by chanding one bit.
+  size_t Mutate_ChangeBit(uint8_t *Data, size_t Size, size_t MaxSize);
 
-/// Mutates data by shuffling bytes.
+  /// Applies one of the above mutations.
-size_t Mutate_ShuffleBytes(uint8_t *Data, size_t Size, size_t MaxSize,
+  /// Returns the new size of data which could be up to MaxSize.
-                           FuzzerRandomBase &Rand);
+  size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize);
-/// Mutates data by erasing a byte.
-size_t Mutate_EraseByte(uint8_t *Data, size_t Size, size_t MaxSize,
-                        FuzzerRandomBase &Rand);
-/// Mutates data by inserting a byte.
-size_t Mutate_InsertByte(uint8_t *Data, size_t Size, size_t MaxSize,
-                         FuzzerRandomBase &Rand);
-/// Mutates data by chanding one byte.
-size_t Mutate_ChangeByte(uint8_t *Data, size_t Size, size_t MaxSize,
-                         FuzzerRandomBase &Rand);
-/// Mutates data by chanding one bit.
-size_t Mutate_ChangeBit(uint8_t *Data, size_t Size, size_t MaxSize,
-                       FuzzerRandomBase &Rand);
 
-/// Applies one of the above mutations.
+  /// Creates a cross-over of two pieces of Data, returns its size.
-/// Returns the new size of data which could be up to MaxSize.
+  size_t CrossOver(const uint8_t *Data1, size_t Size1, const uint8_t *Data2,
-size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize,
+                   size_t Size2, uint8_t *Out, size_t MaxOutSize);
-              FuzzerRandomBase &Rand);
 
-/// Creates a cross-over of two pieces of Data, returns its size.
+ private:
-size_t CrossOver(const uint8_t *Data1, size_t Size1, const uint8_t *Data2,
+  FuzzerRandomBase &Rand;
-                 size_t Size2, uint8_t *Out, size_t MaxOutSize,
+};
-                 FuzzerRandomBase &Rand);
 
+// For backward compatibility only, deprecated.
+static inline size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize,
+                            FuzzerRandomBase &Rand) {
+  MutationDispatcher MD(Rand);
+  return MD.Mutate(Data, Size, MaxSize);
+}
 
 /** An abstract class that allows to use user-supplied mutators with libFuzzer.
 
@@ -122,15 +127,14 @@ class UserSuppliedFuzzer {
   /// Mutates 'Size' bytes of data in 'Data' inplace into up to 'MaxSize' bytes,
   /// returns the new size of the data, which should be positive.
   virtual size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize) {
-    return ::fuzzer::Mutate(Data, Size, MaxSize, GetRand());
+    return MD.Mutate(Data, Size, MaxSize);
   }
   /// Crosses 'Data1' and 'Data2', writes up to 'MaxOutSize' bytes into Out,
   /// returns the number of bytes written, which should be positive.
   virtual size_t CrossOver(const uint8_t *Data1, size_t Size1,
                            const uint8_t *Data2, size_t Size2,
                            uint8_t *Out, size_t MaxOutSize) {
-    return ::fuzzer::CrossOver(Data1, Size1, Data2, Size2, Out, MaxOutSize,
+    return MD.CrossOver(Data1, Size1, Data2, Size2, Out, MaxOutSize);
-                               GetRand());
   }
   virtual ~UserSuppliedFuzzer();
 
@@ -139,6 +143,7 @@ class UserSuppliedFuzzer {
  private:
   bool OwnRand = false;
   FuzzerRandomBase *Rand;
+  MutationDispatcher MD;
 };
 
 /// Runs the fuzzing with the UserSuppliedFuzzer.

llvm/lib/Fuzzer/FuzzerMutate.cpp

@@ -35,8 +35,8 @@ static char RandCh(FuzzerRandomBase &Rand) {
   return Special[Rand(sizeof(Special) - 1)];
 }
 
-size_t Mutate_ShuffleBytes(uint8_t *Data, size_t Size, size_t MaxSize,
+size_t MutationDispatcher::Mutate_ShuffleBytes(uint8_t *Data, size_t Size,
-                           FuzzerRandomBase &Rand) {
+                                               size_t MaxSize) {
   assert(Size);
   size_t ShuffleAmount = Rand(std::min(Size, 8UL)) + 1;  // [1,8] and <= Size.
   size_t ShuffleStart = Rand(Size - ShuffleAmount);
@@ -46,8 +46,8 @@ size_t Mutate_ShuffleBytes(uint8_t *Data, size_t Size, size_t MaxSize,
   return Size;
 }
 
-size_t Mutate_EraseByte(uint8_t *Data, size_t Size, size_t MaxSize,
+size_t MutationDispatcher::Mutate_EraseByte(uint8_t *Data, size_t Size,
-                        FuzzerRandomBase &Rand) {
+                                            size_t MaxSize) {
   assert(Size);
   if (Size == 1) return Size;
   size_t Idx = Rand(Size);
@@ -56,8 +56,8 @@ size_t Mutate_EraseByte(uint8_t *Data, size_t Size, size_t MaxSize,
   return Size - 1;
 }
 
-size_t Mutate_InsertByte(uint8_t *Data, size_t Size, size_t MaxSize,
+size_t MutationDispatcher::Mutate_InsertByte(uint8_t *Data, size_t Size,
-                         FuzzerRandomBase &Rand) {
+                                             size_t MaxSize) {
   if (Size == MaxSize) return Size;
   size_t Idx = Rand(Size + 1);
   // Insert new value at Data[Idx].
@@ -66,23 +66,22 @@ size_t Mutate_InsertByte(uint8_t *Data, size_t Size, size_t MaxSize,
   return Size + 1;
 }
 
-size_t Mutate_ChangeByte(uint8_t *Data, size_t Size, size_t MaxSize,
+size_t MutationDispatcher::Mutate_ChangeByte(uint8_t *Data, size_t Size,
-                         FuzzerRandomBase &Rand) {
+                                             size_t MaxSize) {
   size_t Idx = Rand(Size);
   Data[Idx] = RandCh(Rand);
   return Size;
 }
 
-size_t Mutate_ChangeBit(uint8_t *Data, size_t Size, size_t MaxSize,
+size_t MutationDispatcher::Mutate_ChangeBit(uint8_t *Data, size_t Size,
-                        FuzzerRandomBase &Rand) {
+                                            size_t MaxSize) {
   size_t Idx = Rand(Size);
   Data[Idx] = FlipRandomBit(Data[Idx], Rand);
   return Size;
 }
 
 // Mutates Data in place, returns new size.
-size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize,
+size_t MutationDispatcher::Mutate(uint8_t *Data, size_t Size, size_t MaxSize) {
-              FuzzerRandomBase &Rand) {
   assert(MaxSize > 0);
   assert(Size <= MaxSize);
   if (Size == 0) {
@@ -92,11 +91,11 @@ size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize,
   }
   assert(Size > 0);
   switch (Rand(5)) {
-  case 0: Size = Mutate_EraseByte(Data, Size, MaxSize, Rand); break;
+  case 0: Size = Mutate_EraseByte(Data, Size, MaxSize); break;
-  case 1: Size = Mutate_InsertByte(Data, Size, MaxSize, Rand); break;
+  case 1: Size = Mutate_InsertByte(Data, Size, MaxSize); break;
-  case 2: Size = Mutate_ChangeByte(Data, Size, MaxSize, Rand); break;
+  case 2: Size = Mutate_ChangeByte(Data, Size, MaxSize); break;
-  case 3: Size = Mutate_ChangeBit(Data, Size, MaxSize, Rand); break;
+  case 3: Size = Mutate_ChangeBit(Data, Size, MaxSize); break;
-  case 4: Size = Mutate_ShuffleBytes(Data, Size, MaxSize, Rand); break;
+  case 4: Size = Mutate_ShuffleBytes(Data, Size, MaxSize); break;
   }
   assert(Size > 0);
   return Size;

llvm/lib/Fuzzer/test/FuzzerUnittest.cpp

@@ -12,6 +12,7 @@ extern "C" void LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
 
 TEST(Fuzzer, CrossOver) {
   FuzzerRandomLibc Rand(0);
+  MutationDispatcher MD(Rand);
   Unit A({0, 1, 2}), B({5, 6, 7});
   Unit C;
   Unit Expected[] = {
@@ -54,8 +55,8 @@ TEST(Fuzzer, CrossOver) {
     std::set<Unit> FoundUnits, ExpectedUnitsWitThisLength;
     for (int Iter = 0; Iter < 3000; Iter++) {
       C.resize(Len);
-      size_t NewSize = CrossOver(A.data(), A.size(), B.data(), B.size(),
+      size_t NewSize = MD.CrossOver(A.data(), A.size(), B.data(), B.size(),
-                                 C.data(), C.size(), Rand);
+                                    C.data(), C.size());
       C.resize(NewSize);
       FoundUnits.insert(C);
     }
@@ -74,8 +75,8 @@ TEST(Fuzzer, Hash) {
   EXPECT_EQ("81fe8bfe87576c3ecb22426f8e57847382917acf", fuzzer::Hash(U));
 }
 
-typedef size_t (*Mutator)(uint8_t *Data, size_t Size, size_t MaxSize,
+typedef size_t (MutationDispatcher::*Mutator)(uint8_t *Data, size_t Size,
-                          FuzzerRandomBase &Rand);
+                                              size_t MaxSize);
 
 void TestEraseByte(Mutator M, int NumIter) {
   uint8_t REM0[8] = {0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
@@ -87,10 +88,11 @@ void TestEraseByte(Mutator M, int NumIter) {
   uint8_t REM6[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x77};
   uint8_t REM7[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66};
   FuzzerRandomLibc Rand(0);
+  MutationDispatcher MD(Rand);
   int FoundMask = 0;
   for (int i = 0; i < NumIter; i++) {
     uint8_t T[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
-    size_t NewSize = M(T, sizeof(T), sizeof(T), Rand);
+    size_t NewSize = (MD.*M)(T, sizeof(T), sizeof(T));
     if (NewSize == 7 && !memcmp(REM0, T, 7)) FoundMask |= 1 << 0;
     if (NewSize == 7 && !memcmp(REM1, T, 7)) FoundMask |= 1 << 1;
     if (NewSize == 7 && !memcmp(REM2, T, 7)) FoundMask |= 1 << 2;
@@ -103,11 +105,12 @@ void TestEraseByte(Mutator M, int NumIter) {
   EXPECT_EQ(FoundMask, 255);
 }
 
-TEST(FuzzerMutate, EraseByte1) { TestEraseByte(Mutate_EraseByte, 100); }
+TEST(FuzzerMutate, EraseByte1) { TestEraseByte(&MutationDispatcher::Mutate_EraseByte, 100); }
-TEST(FuzzerMutate, EraseByte2) { TestEraseByte(Mutate, 1000); }
+TEST(FuzzerMutate, EraseByte2) { TestEraseByte(&MutationDispatcher::Mutate, 1000); }
 
 void TestInsertByte(Mutator M, int NumIter) {
   FuzzerRandomLibc Rand(0);
+  MutationDispatcher MD(Rand);
   int FoundMask = 0;
   uint8_t INS0[8] = {0xF1, 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66};
   uint8_t INS1[8] = {0x00, 0xF2, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66};
@@ -119,7 +122,7 @@ void TestInsertByte(Mutator M, int NumIter) {
   uint8_t INS7[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0xF8};
   for (int i = 0; i < NumIter; i++) {
     uint8_t T[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66};
-    size_t NewSize = M(T, 7, 8, Rand);
+    size_t NewSize = (MD.*M)(T, 7, 8);
     if (NewSize == 8 && !memcmp(INS0, T, 8)) FoundMask |= 1 << 0;
     if (NewSize == 8 && !memcmp(INS1, T, 8)) FoundMask |= 1 << 1;
     if (NewSize == 8 && !memcmp(INS2, T, 8)) FoundMask |= 1 << 2;
@@ -132,11 +135,12 @@ void TestInsertByte(Mutator M, int NumIter) {
   EXPECT_EQ(FoundMask, 255);
 }
 
-TEST(FuzzerMutate, InsertByte1) { TestInsertByte(Mutate_InsertByte, 1 << 15); }
+TEST(FuzzerMutate, InsertByte1) { TestInsertByte(&MutationDispatcher::Mutate_InsertByte, 1 << 15); }
-TEST(FuzzerMutate, InsertByte2) { TestInsertByte(Mutate, 1 << 17); }
+TEST(FuzzerMutate, InsertByte2) { TestInsertByte(&MutationDispatcher::Mutate, 1 << 17); }
 
 void TestChangeByte(Mutator M, int NumIter) {
   FuzzerRandomLibc Rand(0);
+  MutationDispatcher MD(Rand);
   int FoundMask = 0;
   uint8_t CH0[8] = {0xF0, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
   uint8_t CH1[8] = {0x00, 0xF1, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
@@ -148,7 +152,7 @@ void TestChangeByte(Mutator M, int NumIter) {
   uint8_t CH7[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0xF7};
   for (int i = 0; i < NumIter; i++) {
     uint8_t T[9] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
-    size_t NewSize = M(T, 8, 9, Rand);
+    size_t NewSize = (MD.*M)(T, 8, 9);
     if (NewSize == 8 && !memcmp(CH0, T, 8)) FoundMask |= 1 << 0;
     if (NewSize == 8 && !memcmp(CH1, T, 8)) FoundMask |= 1 << 1;
     if (NewSize == 8 && !memcmp(CH2, T, 8)) FoundMask |= 1 << 2;
@@ -161,11 +165,12 @@ void TestChangeByte(Mutator M, int NumIter) {
   EXPECT_EQ(FoundMask, 255);
 }
 
-TEST(FuzzerMutate, ChangeByte1) { TestChangeByte(Mutate_ChangeByte, 1 << 15); }
+TEST(FuzzerMutate, ChangeByte1) { TestChangeByte(&MutationDispatcher::Mutate_ChangeByte, 1 << 15); }
-TEST(FuzzerMutate, ChangeByte2) { TestChangeByte(Mutate, 1 << 17); }
+TEST(FuzzerMutate, ChangeByte2) { TestChangeByte(&MutationDispatcher::Mutate, 1 << 17); }
 
 void TestChangeBit(Mutator M, int NumIter) {
   FuzzerRandomLibc Rand(0);
+  MutationDispatcher MD(Rand);
   int FoundMask = 0;
   uint8_t CH0[8] = {0x01, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
   uint8_t CH1[8] = {0x00, 0x13, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
@@ -177,7 +182,7 @@ void TestChangeBit(Mutator M, int NumIter) {
   uint8_t CH7[8] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0xF7};
   for (int i = 0; i < NumIter; i++) {
     uint8_t T[9] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
-    size_t NewSize = M(T, 8, 9, Rand);
+    size_t NewSize = (MD.*M)(T, 8, 9);
     if (NewSize == 8 && !memcmp(CH0, T, 8)) FoundMask |= 1 << 0;
     if (NewSize == 8 && !memcmp(CH1, T, 8)) FoundMask |= 1 << 1;
     if (NewSize == 8 && !memcmp(CH2, T, 8)) FoundMask |= 1 << 2;
@@ -190,11 +195,12 @@ void TestChangeBit(Mutator M, int NumIter) {
   EXPECT_EQ(FoundMask, 255);
 }
 
-TEST(FuzzerMutate, ChangeBit1) { TestChangeBit(Mutate_ChangeBit, 1 << 16); }
+TEST(FuzzerMutate, ChangeBit1) { TestChangeBit(&MutationDispatcher::Mutate_ChangeBit, 1 << 16); }
-TEST(FuzzerMutate, ChangeBit2) { TestChangeBit(Mutate, 1 << 18); }
+TEST(FuzzerMutate, ChangeBit2) { TestChangeBit(&MutationDispatcher::Mutate, 1 << 18); }
 
 void TestShuffleBytes(Mutator M, int NumIter) {
   FuzzerRandomLibc Rand(0);
+  MutationDispatcher MD(Rand);
   int FoundMask = 0;
   uint8_t CH0[7] = {0x00, 0x22, 0x11, 0x33, 0x44, 0x55, 0x66};
   uint8_t CH1[7] = {0x11, 0x00, 0x33, 0x22, 0x44, 0x55, 0x66};
@@ -203,7 +209,7 @@ void TestShuffleBytes(Mutator M, int NumIter) {
   uint8_t CH4[7] = {0x00, 0x11, 0x22, 0x33, 0x55, 0x44, 0x66};
   for (int i = 0; i < NumIter; i++) {
     uint8_t T[7] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66};
-    size_t NewSize = M(T, 7, 7, Rand);
+    size_t NewSize = (MD.*M)(T, 7, 7);
     if (NewSize == 7 && !memcmp(CH0, T, 7)) FoundMask |= 1 << 0;
     if (NewSize == 7 && !memcmp(CH1, T, 7)) FoundMask |= 1 << 1;
     if (NewSize == 7 && !memcmp(CH2, T, 7)) FoundMask |= 1 << 2;
@@ -213,8 +219,8 @@ void TestShuffleBytes(Mutator M, int NumIter) {
   EXPECT_EQ(FoundMask, 31);
 }
 
-TEST(FuzzerMutate, ShuffleBytes1) { TestShuffleBytes(Mutate_ShuffleBytes, 1 << 15); }
+TEST(FuzzerMutate, ShuffleBytes1) { TestShuffleBytes(&MutationDispatcher::Mutate_ShuffleBytes, 1 << 15); }
-TEST(FuzzerMutate, ShuffleBytes2) { TestShuffleBytes(Mutate, 1 << 16); }
+TEST(FuzzerMutate, ShuffleBytes2) { TestShuffleBytes(&MutationDispatcher::Mutate, 1 << 16); }
 
 TEST(FuzzerDictionary, ParseOneDictionaryEntry) {
   Unit U;