From 46fa0aabcb02fe3c0ce378ac24e4180ce8dee94e Mon Sep 17 00:00:00 2001
From: Kostya Serebryany <kcc@google.com>
Date: Thu, 7 May 2015 18:32:29 +0000
Subject: [PATCH] [lib/Fuzzer] minor refactoring/simplification, NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236757 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Fuzzer/FuzzerDFSan.cpp  |  7 +++++
 lib/Fuzzer/FuzzerInternal.h |  6 ++--
 lib/Fuzzer/FuzzerLoop.cpp   | 59 +++++++++++++++++++------------------
 3 files changed, 41 insertions(+), 31 deletions(-)

diff --git a/lib/Fuzzer/FuzzerDFSan.cpp b/lib/Fuzzer/FuzzerDFSan.cpp
index e3fda1615b8..a17ab60c788 100644
--- a/lib/Fuzzer/FuzzerDFSan.cpp
+++ b/lib/Fuzzer/FuzzerDFSan.cpp
@@ -287,4 +287,11 @@ void dfsan_weak_hook_memcmp(void *caller_pc, const void *s1, const void *s2,
   dfsan_label L2 = dfsan_read_label(s2, n);
   DFSan->DFSanCmpCallback(PC, n, ICMP_EQ, S1, S2, L1, L2);
 }
+
+void __sanitizer_cov_trace_cmp(uint64_t SizeAndType, uint64_t Arg1,
+                               uint64_t Arg2) {
+  // This symbol will be present if dfsan is disabled on the given function.
+  // FIXME: implement poor man's taint analysis here (w/o dfsan).
+}
+
 }  // extern "C"
diff --git a/lib/Fuzzer/FuzzerInternal.h b/lib/Fuzzer/FuzzerInternal.h
index 8948e3478c5..6fd3bfe799c 100644
--- a/lib/Fuzzer/FuzzerInternal.h
+++ b/lib/Fuzzer/FuzzerInternal.h
@@ -61,7 +61,7 @@ class Fuzzer {
   };
   Fuzzer(UserCallback Callback, FuzzingOptions Options);
   void AddToCorpus(const Unit &U) { Corpus.push_back(U); }
-  size_t Loop(size_t NumIterations);
+  void Loop(size_t NumIterations);
   void ShuffleAndMinimize();
   void InitializeDFSan();
   size_t CorpusSize() const { return Corpus.size(); }
@@ -85,8 +85,10 @@ class Fuzzer {
  private:
   void AlarmCallback();
   void ExecuteCallback(const Unit &U);
-  size_t MutateAndTestOne(Unit *U);
+  void MutateAndTestOne(Unit *U);
+  void ReportNewCoverage(size_t NewCoverage, const Unit &U);
   size_t RunOne(const Unit &U);
+  void RunOneAndUpdateCorpus(const Unit &U);
   size_t RunOneMaximizeTotalCoverage(const Unit &U);
   size_t RunOneMaximizeFullCoverageSet(const Unit &U);
   size_t RunOneMaximizeCoveragePairs(const Unit &U);
diff --git a/lib/Fuzzer/FuzzerLoop.cpp b/lib/Fuzzer/FuzzerLoop.cpp
index 3a19b22653d..57893e0f1fe 100644
--- a/lib/Fuzzer/FuzzerLoop.cpp
+++ b/lib/Fuzzer/FuzzerLoop.cpp
@@ -143,6 +143,12 @@ size_t Fuzzer::RunOne(const Unit &U) {
   return Res;
 }
 
+void Fuzzer::RunOneAndUpdateCorpus(const Unit &U) {
+  if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+    return;
+  ReportNewCoverage(RunOne(U), U);
+}
+
 static uintptr_t HashOfArrayOfPCs(uintptr_t *PCs, uintptr_t NumPCs) {
   uintptr_t Res = 0;
   for (uintptr_t i = 0; i < NumPCs; i++) {
@@ -259,55 +265,50 @@ void Fuzzer::SaveCorpus() {
               << Options.OutputCorpus << "\n";
 }
 
-size_t Fuzzer::MutateAndTestOne(Unit *U) {
-  size_t NewUnits = 0;
+void Fuzzer::ReportNewCoverage(size_t NewCoverage, const Unit &U) {
+  if (!NewCoverage) return;
+  Corpus.push_back(U);
+  PrintStats("NEW   ", NewCoverage, "");
+  if (Options.Verbosity) {
+    std::cerr << " L: " << U.size();
+    if (U.size() < 30) {
+      std::cerr << " ";
+      PrintUnitInASCIIOrTokens(U, "\t");
+      Print(U);
+    }
+    std::cerr << "\n";
+  }
+  WriteToOutputCorpus(U);
+  if (Options.ExitOnFirst)
+    exit(0);
+}
+
+void Fuzzer::MutateAndTestOne(Unit *U) {
   for (int i = 0; i < Options.MutateDepth; i++) {
-    if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
-      return NewUnits;
     MutateWithDFSan(U);
     Mutate(U, Options.MaxLen);
-    size_t NewCoverage = RunOne(*U);
-    if (NewCoverage) {
-      Corpus.push_back(*U);
-      NewUnits++;
-      PrintStats("NEW   ", NewCoverage, "");
-      if (Options.Verbosity) {
-        std::cerr << " L: " << U->size();
-        if (U->size() < 30) {
-          std::cerr << " ";
-          PrintUnitInASCIIOrTokens(*U, "\t");
-          Print(*U);
-        }
-        std::cerr << "\n";
-      }
-      WriteToOutputCorpus(*U);
-      if (Options.ExitOnFirst)
-        exit(0);
-    }
+    RunOneAndUpdateCorpus(*U);
   }
-  return NewUnits;
 }
 
-size_t Fuzzer::Loop(size_t NumIterations) {
-  size_t NewUnits = 0;
+void Fuzzer::Loop(size_t NumIterations) {
   for (size_t i = 1; i <= NumIterations; i++) {
     for (size_t J1 = 0; J1 < Corpus.size(); J1++) {
       if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
-        return NewUnits;
+        return;
       // First, simply mutate the unit w/o doing crosses.
       CurrentUnit = Corpus[J1];
-      NewUnits += MutateAndTestOne(&CurrentUnit);
+      MutateAndTestOne(&CurrentUnit);
       // Now, cross with others.
       if (Options.DoCrossOver) {
         for (size_t J2 = 0; J2 < Corpus.size(); J2++) {
           CurrentUnit.clear();
           CrossOver(Corpus[J1], Corpus[J2], &CurrentUnit, Options.MaxLen);
-          NewUnits += MutateAndTestOne(&CurrentUnit);
+          MutateAndTestOne(&CurrentUnit);
         }
       }
     }
   }
-  return NewUnits;
 }
 
 }  // namespace fuzzer
-- 
2.34.1