[llvm] r256882 - [libfuzzer] print_new_cov_pcs experimental option.

[Mike Aizatsky via llvm-commits]

Author: aizatsky
Date: Tue Jan  5 18:21:22 2016
New Revision: 256882

URL: http://llvm.org/viewvc/llvm-project?rev=256882&view=rev
Log:
[libfuzzer] print_new_cov_pcs experimental option.

Differential Revision: http://reviews.llvm.org/D15901

Modified:
    llvm/trunk/lib/Fuzzer/FuzzerDriver.cpp
    llvm/trunk/lib/Fuzzer/FuzzerFlags.def
    llvm/trunk/lib/Fuzzer/FuzzerInternal.h
    llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp
    llvm/trunk/lib/Fuzzer/test/fuzzer.test

Modified: llvm/trunk/lib/Fuzzer/FuzzerDriver.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerDriver.cpp?rev=256882&r1=256881&r2=256882&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerDriver.cpp (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerDriver.cpp Tue Jan  5 18:21:22 2016
@@ -281,6 +281,7 @@ int FuzzerDriver(const std::vector<std::
   if (Flags.verbosity > 0 && !Dictionary.empty())
     Printf("Dictionary: %zd entries\n", Dictionary.size());
   Options.SaveArtifacts = !Flags.test_single_input;
+  Options.PrintNewCovPcs = Flags.print_new_cov_pcs;
 
   Fuzzer F(USF, Options);
 

Modified: llvm/trunk/lib/Fuzzer/FuzzerFlags.def
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerFlags.def?rev=256882&r1=256881&r2=256882&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerFlags.def (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerFlags.def Tue Jan  5 18:21:22 2016
@@ -72,3 +72,5 @@ FUZZER_FLAG_STRING(exact_artifact_path,
 FUZZER_FLAG_INT(drill, 0, "Experimental: fuzz using a single unit as the seed "
                           "corpus, then merge with the initial corpus")
 FUZZER_FLAG_INT(output_csv, 0, "Enable pulse output in CSV format.")
+FUZZER_FLAG_INT(print_new_cov_pcs, 0, "If 1, print out new covered pcs.")
+

Modified: llvm/trunk/lib/Fuzzer/FuzzerInternal.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerInternal.h?rev=256882&r1=256881&r2=256882&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerInternal.h (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerInternal.h Tue Jan  5 18:21:22 2016
@@ -97,6 +97,7 @@ class Fuzzer {
     bool SaveArtifacts = true;
     bool PrintNEW = true;  // Print a status line when new units are found;
     bool OutputCSV = false;
+    bool PrintNewCovPcs = false;
   };
   Fuzzer(UserSuppliedFuzzer &USF, FuzzingOptions Options);
   void AddToCorpus(const Unit &U) { Corpus.push_back(U); }
@@ -188,6 +189,7 @@ class Fuzzer {
   long EpochOfLastReadOfOutputCorpus = 0;
   size_t LastRecordedBlockCoverage = 0;
   size_t LastRecordedCallerCalleeCoverage = 0;
+  size_t LastCoveragePcBufferLen = 0;
 };
 
 class SimpleUserSuppliedFuzzer: public UserSuppliedFuzzer {

Modified: llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp?rev=256882&r1=256881&r2=256882&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerLoop.cpp Tue Jan  5 18:21:22 2016
@@ -31,6 +31,8 @@ void __sanitizer_set_death_callback(void
 __attribute__((weak)) size_t __sanitizer_get_number_of_counters();
 __attribute__((weak))
 uintptr_t __sanitizer_update_counter_bitset_and_clear_counters(uint8_t *bitset);
+__attribute__((weak)) uintptr_t
+__sanitizer_get_coverage_pc_buffer(uintptr_t **data);
 }
 
 namespace fuzzer {
@@ -249,7 +251,21 @@ void Fuzzer::ExecuteCallback(const Unit
 
 size_t Fuzzer::RecordBlockCoverage() {
   CHECK_WEAK_API_FUNCTION(__sanitizer_get_total_unique_coverage);
-  return LastRecordedBlockCoverage = __sanitizer_get_total_unique_coverage();
+  uintptr_t PrevCoverage = LastRecordedBlockCoverage;
+  LastRecordedBlockCoverage = __sanitizer_get_total_unique_coverage();
+
+  if (PrevCoverage == LastRecordedBlockCoverage || !Options.PrintNewCovPcs)
+    return LastRecordedBlockCoverage;
+
+  uintptr_t PrevBufferLen = LastCoveragePcBufferLen;
+  uintptr_t *CoverageBuf;
+  LastCoveragePcBufferLen = __sanitizer_get_coverage_pc_buffer(&CoverageBuf);
+  assert(CoverageBuf);
+  for (size_t i = PrevBufferLen; i < LastCoveragePcBufferLen; ++i) {
+    Printf("0x%x\n", CoverageBuf[i]);
+  }
+
+  return LastRecordedBlockCoverage;
 }
 
 size_t Fuzzer::RecordCallerCalleeCoverage() {

Modified: llvm/trunk/lib/Fuzzer/test/fuzzer.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/test/fuzzer.test?rev=256882&r1=256881&r2=256882&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/test/fuzzer.test (original)
+++ llvm/trunk/lib/Fuzzer/test/fuzzer.test Tue Jan  5 18:21:22 2016
@@ -30,3 +30,9 @@ RUN:     LLVMFuzzer-SimpleDictionaryTest
 
 RUN: not LLVMFuzzer-UninstrumentedTest-Uninstrumented 2>&1 | FileCheck %s --check-prefix=UNINSTRUMENTED
 UNINSTRUMENTED: ERROR: __sanitizer_set_death_callback is not defined. Exiting.
+
+RUN: LLVMFuzzer-SimpleTest -print_new_cov_pcs=1 2>&1 | FileCheck %s --check-prefix=PCS
+PCS:{{^0x[a-f0-9]+}}
+PCS:NEW
+PCS:BINGO
+