1 files changed, 17 insertions, 13 deletions
diff --git a/lib/Fuzzer/FuzzerLoop.cpp b/lib/Fuzzer/FuzzerLoop.cpp
index 6816f3af8a6f..8ac7a847aef7 100644
--- a/lib/Fuzzer/FuzzerLoop.cpp
+++ b/lib/Fuzzer/FuzzerLoop.cpp
@@ -114,7 +114,6 @@ Fuzzer::Fuzzer(UserCallback CB, InputCorpus &Corpus, MutationDispatcher &MD,
     : CB(CB), Corpus(Corpus), MD(MD), Options(Options) {
   if (EF->__sanitizer_set_death_callback)
     EF->__sanitizer_set_death_callback(StaticDeathCallback);
-  InitializeTraceState();
   assert(!F);
   F = this;
   TPC.ResetMaps();
@@ -403,22 +402,29 @@ bool Fuzzer::RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile,
 
   ExecuteCallback(Data, Size);
 
-  FeatureSetTmp.clear();
+  UniqFeatureSetTmp.clear();
+  size_t FoundUniqFeaturesOfII = 0;
   size_t NumUpdatesBefore = Corpus.NumFeatureUpdates();
   TPC.CollectFeatures([&](size_t Feature) {
-    Corpus.AddFeature(Feature, Size, Options.Shrink);
-    if (Options.ReduceInputs)
-      FeatureSetTmp.push_back(Feature);
+    if (Corpus.AddFeature(Feature, Size, Options.Shrink))
+      UniqFeatureSetTmp.push_back(Feature);
+    if (Options.ReduceInputs && II)
+      if (std::binary_search(II->UniqFeatureSet.begin(),
+                             II->UniqFeatureSet.end(), Feature))
+        FoundUniqFeaturesOfII++;
   });
   PrintPulseAndReportSlowInput(Data, Size);
   size_t NumNewFeatures = Corpus.NumFeatureUpdates() - NumUpdatesBefore;
   if (NumNewFeatures) {
     Corpus.AddToCorpus({Data, Data + Size}, NumNewFeatures, MayDeleteFile,
-                       FeatureSetTmp);
+                       UniqFeatureSetTmp);
     CheckExitOnSrcPosOrItem();
     return true;
   }
-  if (II && Corpus.TryToReplace(II, Data, Size, FeatureSetTmp)) {
+  if (II && FoundUniqFeaturesOfII &&
+      FoundUniqFeaturesOfII == II->UniqFeatureSet.size() &&
+      II->U.size() > Size) {
+    Corpus.Replace(II, {Data, Data + Size});
     CheckExitOnSrcPosOrItem();
     return true;
   }
@@ -501,10 +507,10 @@ void Fuzzer::WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix) {
     Printf("Base64: %s\n", Base64(U).c_str());
 }
 
-void Fuzzer::PrintStatusForNewUnit(const Unit &U) {
+void Fuzzer::PrintStatusForNewUnit(const Unit &U, const char *Text) {
   if (!Options.PrintNEW)
     return;
-  PrintStats("NEW   ", "");
+  PrintStats(Text, "");
   if (Options.Verbosity) {
     Printf(" L: %zd ", U.size());
     MD.PrintMutationSequence();
@@ -515,7 +521,8 @@ void Fuzzer::PrintStatusForNewUnit(const Unit &U) {
 void Fuzzer::ReportNewCoverage(InputInfo *II, const Unit &U) {
   II->NumSuccessfullMutations++;
   MD.RecordSuccessfulMutationSequence();
-  PrintStatusForNewUnit(U);
+  PrintStatusForNewUnit(U, II->Reduced ? "REDUCE" :
+                                         "NEW   ");
   WriteToOutputCorpus(U);
   NumberOfNewUnitsAdded++;
   TPC.PrintNewPCs();
@@ -600,13 +607,10 @@ void Fuzzer::MutateAndTestOne() {
     assert(NewSize > 0 && "Mutator returned empty unit");
     assert(NewSize <= CurrentMaxMutationLen && "Mutator return overisized unit");
     Size = NewSize;
-    if (i == 0)
-      StartTraceRecording();
     II.NumExecutedMutations++;
     if (RunOne(CurrentUnitData, Size, /*MayDeleteFile=*/true, &II))
       ReportNewCoverage(&II, {CurrentUnitData, CurrentUnitData + Size});
 
-    StopTraceRecording();
     TryDetectingAMemoryLeak(CurrentUnitData, Size,
                             /*DuringInitialCorpusExecution*/ false);
   }