[PATCH] D73776: Entropic: Boosting LibFuzzer Performance

[Vitaly Buka via Phabricator via llvm-commits]

vitalybuka added inline comments.


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Comment at: compiler-rt/lib/fuzzer/FuzzerCorpus.h:59
+public:
+  size_t NumExecutedMutations = 0;
+  InputCorpus(const std::string &OutputCorpus, bool Entropic,
----------------
please make field private and add access method if it's needed outside


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Comment at: compiler-rt/lib/fuzzer/FuzzerCorpus.h:242
 
+  bool DeleteFeatureFreq(InputInfo *II, uint32_t Idx) {
+    if (II->FeatureFreqs.empty())
----------------
DeleteFeatureFreq -> InputInfo::DeleteFeatureFreq


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Comment at: compiler-rt/lib/fuzzer/FuzzerCorpus.h:264
+           FreqOfMostAbundantRareFeature > ConsideredRare) {
+      uint32_t ST_mostAbundantRareFeatureIdx =
+          RareFeatures[0]; // 1st most abd feature index
----------------
uint32_t MostAbundantRareFeatureIdx[2] = {}
or 
just 
MostAbundantRareFeatureIdx1
MostAbundantRareFeatureIdx2


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Comment at: compiler-rt/lib/fuzzer/FuzzerCorpus.h:336
 
+  void UpdateFeatureFrequency(InputInfo *II, size_t Idx) {
+    uint32_t Idx32 = Idx % kFeatureSetSize;
----------------
InputInfo::UpdateFeatureFrequency


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Comment at: compiler-rt/lib/fuzzer/FuzzerCorpus.h:387
+  // let II->Energy approach the true entropy from above.
+  void UpdateEnergy(InputInfo *II, size_t GlobalNumberOfFeatures) {
+    long double Energy = 0.0L;
----------------
InputInfo::UpdateEnergy


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Comment at: compiler-rt/lib/fuzzer/FuzzerCorpus.h:388
+  void UpdateEnergy(InputInfo *II, size_t GlobalNumberOfFeatures) {
+    long double Energy = 0.0L;
+    size_t SumIncidence = 0;
----------------
"long double" is still there?



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Comment at: compiler-rt/lib/fuzzer/FuzzerFlags.def:156
      "will choose the focus functions automatically.")
+FUZZER_FLAG_INT(entropic, 0, "Experimental. Enables entropic power schedule.")
+FUZZER_FLAG_INT(considered_rare, 0xFF, "Experimental. If entropic is enabled, "
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vitalybuka wrote:
> entropic -> focus_rare_features
> 
> 
> Not sure how, it would be nice to rename sparse_energy_updates as something meaningful to libfuzzer user, to make it explain behavior change, not implementation details like now.
many of comments are marked as "Done" but I see no changes.



CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D73776/new/

https://reviews.llvm.org/D73776