[libFuzzer] in autofocus mode, give more weight to functions with DFT
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@363473 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/FuzzerDataFlowTrace.cpp b/FuzzerDataFlowTrace.cpp
index c7200a3..99ff918 100644
--- a/FuzzerDataFlowTrace.cpp
+++ b/FuzzerDataFlowTrace.cpp
@@ -42,11 +42,16 @@
bool BlockCoverage::AppendCoverage(std::istream &IN) {
std::string L;
while (std::getline(IN, L, '\n')) {
- if (L.empty() || L[0] != 'C')
- continue; // Ignore non-coverage lines.
+ if (L.empty())
+ continue;
std::stringstream SS(L.c_str() + 1);
size_t FunctionId = 0;
SS >> FunctionId;
+ if (L[0] == 'F') {
+ FunctionsWithDFT.insert(FunctionId);
+ continue;
+ }
+ if (L[0] != 'C') continue;
Vector<uint32_t> CoveredBlocks;
while (true) {
uint32_t BB = 0;
@@ -87,9 +92,12 @@
auto Counters = It.second;
assert(FunctionID < NumFunctions);
auto &Weight = Res[FunctionID];
- Weight = 1000.; // this function is covered.
+ // Give higher weight if the function has a DFT.
+ Weight = FunctionsWithDFT.count(FunctionID) ? 1000. : 1;
+ // Give higher weight to functions with less frequently seen basic blocks.
Weight /= SmallestNonZeroCounter(Counters);
- Weight *= NumberOfUncoveredBlocks(Counters) + 1; // make sure it's not 0.
+ // Give higher weight to functions with the most uncovered basic blocks.
+ Weight *= NumberOfUncoveredBlocks(Counters) + 1;
}
return Res;
}