[libFuzzer] add an experimental flag -focus_function: libFuzzer will try to focus on inputs that trigger that function

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@332554 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/fuzzer/FuzzerTracePC.h b/lib/fuzzer/FuzzerTracePC.h
index d68da76b2..e1db5127c 100644
--- a/lib/fuzzer/FuzzerTracePC.h
+++ b/lib/fuzzer/FuzzerTracePC.h
@@ -131,6 +131,9 @@ class TracePC {
       CB(PC);
   }
 
+  void SetFocusFunction(const std::string &FuncName);
+  bool ObservedFocusFunction();
+
 private:
   bool UseCounters = false;
   bool UseValueProfile = false;
@@ -163,6 +166,9 @@ private:
   Set<uintptr_t> ObservedPCs;
   Set<uintptr_t> ObservedFuncs;
 
+  std::pair<size_t, size_t> FocusFunction = {-1, -1};  // Module and PC IDs.
+
+
   ValueBitMap ValueProfileMap;
   uintptr_t InitialStack;
 };