[llvm] r285147 - [libFuzzer] simplify the code in TracePC::HandleTrace a bit more

[Kostya Serebryany via llvm-commits]

Author: kcc
Date: Tue Oct 25 19:42:52 2016
New Revision: 285147

URL: http://llvm.org/viewvc/llvm-project?rev=285147&view=rev
Log:
[libFuzzer] simplify the code in TracePC::HandleTrace a bit more

Modified:
    llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp
    llvm/trunk/lib/Fuzzer/FuzzerTracePC.cpp
    llvm/trunk/lib/Fuzzer/FuzzerTracePC.h

Modified: llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp?rev=285147&r1=285146&r2=285147&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp Tue Oct 25 19:42:52 2016
@@ -381,15 +381,14 @@ void Fuzzer::SetMaxMutationLen(size_t Ma
 
 void Fuzzer::CheckExitOnSrcPosOrItem() {
   if (!Options.ExitOnSrcPos.empty()) {
-    uintptr_t *PCIDs;
-    if (size_t NumNewPCIDs = TPC.GetNewPCIDs(&PCIDs)) {
-      for (size_t i = 0; i < NumNewPCIDs; i++) {
-        std::string Descr = DescribePC("%L", TPC.GetPCbyPCID(PCIDs[i]));
-        if (Descr.find(Options.ExitOnSrcPos) != std::string::npos) {
-          Printf("INFO: found line matching '%s', exiting.\n",
-                 Options.ExitOnSrcPos.c_str());
-          _Exit(0);
-        }
+    for (size_t i = 1, N = TPC.GetNumPCs(); i < N; i++) {
+      uintptr_t PC = TPC.GetPC(i);
+      if (!PC) continue;
+      std::string Descr = DescribePC("%L", PC);
+      if (Descr.find(Options.ExitOnSrcPos) != std::string::npos) {
+        Printf("INFO: found line matching '%s', exiting.\n",
+               Options.ExitOnSrcPos.c_str());
+        _Exit(0);
       }
     }
   }

Modified: llvm/trunk/lib/Fuzzer/FuzzerTracePC.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerTracePC.cpp?rev=285147&r1=285146&r2=285147&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerTracePC.cpp (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerTracePC.cpp Tue Oct 25 19:42:52 2016
@@ -30,14 +30,10 @@ TracePC TPC;
 void TracePC::HandleTrace(uint32_t *Guard, uintptr_t PC) {
   uint32_t Idx = *Guard;
   if (!Idx) return;
+  if (!PCs[Idx % kNumPCs])
+    PCs[Idx % kNumPCs] = PC;
   uint8_t *CounterPtr = &Counters[Idx % kNumCounters];
   uint8_t Counter = *CounterPtr;
-  if (Counter == 0) {
-    if (!PCs[Idx % kNumPCs]) {
-      AddNewPCID(Idx);
-      PCs[Idx % kNumPCs] = PC;
-    }
-  }
   if (UseCounters) {
     if (Counter < 128)
       *CounterPtr = Counter + 1;
@@ -51,7 +47,7 @@ void TracePC::HandleTrace(uint32_t *Guar
 
 size_t TracePC::GetTotalPCCoverage() {
   size_t Res = 0;
-  for (size_t i = 0; i < Min(NumGuards+1, kNumPCs); i++)
+  for (size_t i = 1; i < GetNumPCs(); i++)
     if (PCs[i])
       Res++;
   return Res;
@@ -140,7 +136,7 @@ void TracePC::PrintNewPCs() {
   if (DoPrintNewPCs) {
     if (!PrintedPCs)
       PrintedPCs = new std::set<uintptr_t>;
-    for (size_t i = 0; i < Min(NumGuards + 1, kNumPCs); i++)
+    for (size_t i = 1; i < GetNumPCs(); i++)
       if (PCs[i] && PrintedPCs->insert(PCs[i]).second)
         PrintPC("\tNEW_PC: %p %F %L\n", "\tNEW_PC: %p\n", PCs[i]);
   }
@@ -156,7 +152,7 @@ void TracePC::PrintCoverage() {
   std::map<std::string, uintptr_t> ModuleOffsets;
   std::set<std::string> CoveredFiles, CoveredFunctions, CoveredLines;
   Printf("COVERAGE:\n");
-  for (size_t i = 0; i < Min(NumGuards + 1, kNumPCs); i++) {
+  for (size_t i = 1; i < GetNumPCs(); i++) {
     if (!PCs[i]) continue;
     std::string FileStr = DescribePC("%s", PCs[i]);
     if (!IsInterestingCoverageFile(FileStr)) continue;

Modified: llvm/trunk/lib/Fuzzer/FuzzerTracePC.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerTracePC.h?rev=285147&r1=285146&r2=285147&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerTracePC.h (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerTracePC.h Tue Oct 25 19:42:52 2016
@@ -61,15 +61,7 @@ class TracePC {
     return UseValueProfile && MaxValueProfileMap->MergeFrom(ValueProfileMap);
   }
 
-  size_t GetNewPCIDs(uintptr_t **NewPCIDsPtr) {
-    *NewPCIDsPtr = NewPCIDs;
-    return Min(kMaxNewPCIDs, NumNewPCIDs);
-  }
-
-  uintptr_t GetPCbyPCID(uintptr_t PCID) { return PCs[PCID]; }
-
   void ResetMaps() {
-    NumNewPCIDs = 0;
     ValueProfileMap.Reset();
     memset(Counters, 0, sizeof(Counters));
   }
@@ -95,19 +87,17 @@ class TracePC {
   TableOfRecentCompares<uint64_t, kTORCSize> TORC8;
 
   void PrintNewPCs();
+  size_t GetNumPCs() const { return Min(kNumPCs, NumGuards + 1); }
+  uintptr_t GetPC(size_t Idx) {
+    assert(Idx < GetNumPCs());
+    return PCs[Idx];
+  }
 
 private:
   bool UseCounters = false;
   bool UseValueProfile = false;
   bool DoPrintNewPCs = false;
 
-  static const size_t kMaxNewPCIDs = 1024;
-  uintptr_t NewPCIDs[kMaxNewPCIDs];
-  size_t NumNewPCIDs = 0;
-  void AddNewPCID(uintptr_t PCID) {
-    NewPCIDs[(NumNewPCIDs++) % kMaxNewPCIDs] = PCID;
-  }
-
   struct Module {
     uint32_t *Start, *Stop;
   };