[libFuzzer] add various debug prints. Also don't mutate based on a cmp trace like (a eq a) or (a neq a)

llvm-svn: 257434
This commit is contained in:
Kostya Serebryany 2016-01-12 02:08:37 +00:00
parent 85159ca224
commit 859e86d962
1 changed files with 28 additions and 5 deletions

View File

@ -76,7 +76,7 @@
#include <algorithm>
#include <cstring>
#include <thread>
#include <unordered_map>
#include <map>
#if !LLVM_FUZZER_SUPPORTS_DFSAN
// Stubs for dfsan for platforms where dfsan does not exist and weak
@ -178,7 +178,7 @@ static void PrintDataByte(uint8_t Byte) {
else if (Byte >= 32 && Byte < 127)
Printf("%c", Byte);
else
Printf("\\x02x", Byte);
Printf("\\x%02x", Byte);
}
static void PrintData(const uint8_t *Data, size_t Size) {
@ -235,7 +235,26 @@ class TraceState {
RecordingTraces = false;
for (size_t i = 0; i < NumMutations; i++) {
auto &M = Mutations[i];
USF.GetMD().AddWordToAutoDictionary(Unit(M.Data, M.Data + M.Size), M.Pos);
Unit U(M.Data, M.Data + M.Size);
if (Options.Verbosity >= 2) {
AutoDictUnitCounts[U]++;
AutoDictAdds++;
if ((AutoDictAdds & (AutoDictAdds - 1)) == 0) {
typedef std::pair<size_t, Unit> CU;
std::vector<CU> CountedUnits;
for (auto &I : AutoDictUnitCounts)
CountedUnits.push_back(std::make_pair(I.second, I.first));
std::sort(CountedUnits.begin(), CountedUnits.end(),
[](const CU &a, const CU &b) { return a.first > b.first; });
Printf("AutoDict:\n");
for (auto &I : CountedUnits) {
Printf(" %zd ", I.first);
PrintData(I.second.data(), I.second.size());
Printf("\n");
}
}
}
USF.GetMD().AddWordToAutoDictionary(U, M.Pos);
}
}
@ -267,6 +286,8 @@ class TraceState {
UserSuppliedFuzzer &USF;
const Fuzzer::FuzzingOptions &Options;
const Unit &CurrentUnit;
std::map<Unit, size_t> AutoDictUnitCounts;
size_t AutoDictAdds = 0;
static thread_local bool IsMyThread;
};
@ -398,15 +419,17 @@ int TraceState::TryToAddDesiredData(const uint8_t *PresentData,
void TraceState::TraceCmpCallback(uintptr_t PC, size_t CmpSize, size_t CmpType,
uint64_t Arg1, uint64_t Arg2) {
if (!RecordingTraces || !IsMyThread) return;
if ((CmpType == ICMP_EQ || CmpType == ICMP_NE) && Arg1 == Arg2)
return; // No reason to mutate.
int Added = 0;
if (Options.Verbosity >= 3)
Printf("TraceCmp %zd/%zd: %p %zd %zd\n", CmpSize, CmpType, PC, Arg1, Arg2);
Added += TryToAddDesiredData(Arg1, Arg2, CmpSize);
Added += TryToAddDesiredData(Arg2, Arg1, CmpSize);
if (!Added && CmpSize == 4 && IsTwoByteData(Arg1) && IsTwoByteData(Arg2)) {
Added += TryToAddDesiredData(Arg1, Arg2, 2);
Added += TryToAddDesiredData(Arg2, Arg1, 2);
}
if (Options.Verbosity >= 3 && Added)
Printf("TraceCmp %zd/%zd: %p %zd %zd\n", CmpSize, CmpType, PC, Arg1, Arg2);
}
void TraceState::TraceMemcmpCallback(size_t CmpSize, const uint8_t *Data1,