[libFuzzer] initial implementation of -data_flow_trace. It parses the data flow trace and prints the summary, but doesn't use the information in any other way yet

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@334058 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/FuzzerLoop.cpp b/FuzzerLoop.cpp
index 9c19ba9..27bd5ee 100644
--- a/FuzzerLoop.cpp
+++ b/FuzzerLoop.cpp
@@ -160,6 +160,7 @@
   CurrentUnitSize = 0;
   memset(BaseSha1, 0, sizeof(BaseSha1));
   TPC.SetFocusFunction(Options.FocusFunction);
+  DFT.Init(Options.DataFlowTrace, Options.FocusFunction);
 }
 
 Fuzzer::~Fuzzer() {}