commit 6937e68f927b6aefe526fcb9db8953f497e6e74d
author kcc <kcc> Fri Jul 28 22:00:56 2017
committer kcc <kcc> Fri Jul 28 22:00:56 2017
tree 782a30f68c1df6f779acb2d4495bec5be75e6096
parent dcc9838c3b94ab58aa432f85a47b09dcd365071b

[libFuzzer] improve support for inline-8bit-counters (make it more correct and faster)

git-svn-id: svn://svn.chromium.org/llvm-project/llvm/trunk/lib/Fuzzer@309443 0b72dbe1-c17f-4bc7-b9db-2b4152be0356

FuzzerTracePC.cpp

diff --git a/FuzzerTracePC.cpp b/FuzzerTracePC.cpp
index 07be441..bf2a611 100644
--- a/FuzzerTracePC.cpp
+++ b/FuzzerTracePC.cpp
@@ -309,6 +309,14 @@
   return Len;
 }
 
+void TracePC::ClearInlineCounters() {
+  for (size_t i = 0; i < NumModulesWithInline8bitCounters; i++) {
+    uint8_t *Beg = ModuleCounters[i].Start;
+    size_t Size = ModuleCounters[i].Stop - Beg;
+    memset(Beg, 0, Size);
+  }
+}
+
 } // namespace fuzzer
 
 extern "C" {
@@ -345,6 +353,10 @@
 }
 
 ATTRIBUTE_INTERFACE
+void __sanitizer_cov_pcs_init(const uint8_t *pcs_beg, const uint8_t *pcs_end) {
+}
+
+ATTRIBUTE_INTERFACE
 ATTRIBUTE_NO_SANITIZE_ALL
 void __sanitizer_cov_trace_pc_indir(uintptr_t Callee) {
   uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));

FuzzerTracePC.h

diff --git a/FuzzerTracePC.h b/FuzzerTracePC.h
index fac2b2b..28301d1 100644
--- a/FuzzerTracePC.h
+++ b/FuzzerTracePC.h
@@ -87,8 +87,11 @@
     ValueProfileMap.Reset();
     memset(Counters(), 0, GetNumPCs());
     ClearExtraCounters();
+    ClearInlineCounters();
   }
 
+  void ClearInlineCounters();
+
   void UpdateFeatureSet(size_t CurrentElementIdx, size_t CurrentElementSize);
   void PrintFeatureSet();
 
@@ -201,8 +204,11 @@
   };
 
   size_t FirstFeature = 0;
-  ForEachNonZeroByte(Counters, Counters + N, FirstFeature, Handle8bitCounter);
-  FirstFeature += N * 8;
+  if (!NumInline8bitCounters) {
+    ForEachNonZeroByte(Counters, Counters + N, FirstFeature, Handle8bitCounter);
+    FirstFeature += N * 8;
+  }
+
   for (size_t i = 0; i < NumModulesWithInline8bitCounters; i++) {
     ForEachNonZeroByte(ModuleCounters[i].Start, ModuleCounters[i].Stop,
                        FirstFeature, Handle8bitCounter);

test/fuzzer-traces-hooks.test

diff --git a/test/fuzzer-traces-hooks.test b/test/fuzzer-traces-hooks.test
index 77ca4b4..3f9f89e 100644
--- a/test/fuzzer-traces-hooks.test
+++ b/test/fuzzer-traces-hooks.test
@@ -3,7 +3,7 @@
 UNSUPPORTED: windows
 CHECK: BINGO
 
-RUN: not LLVMFuzzer-MemcmpTest               -seed=1 -runs=2000000   2>&1 | FileCheck %s
+RUN: not LLVMFuzzer-MemcmpTest               -seed=1 -runs=10000000   2>&1 | FileCheck %s
 RUN: not LLVMFuzzer-StrncmpTest              -seed=1 -runs=2000000   2>&1 | FileCheck %s
 RUN: not LLVMFuzzer-StrcmpTest               -seed=1 -runs=2000000   2>&1 | FileCheck %s
 RUN: not LLVMFuzzer-StrstrTest               -seed=1 -runs=2000000   2>&1 | FileCheck %s