[tsan] Don't instrument __llvm_gcov_global_state_pred or __llvm_gcda*

r274801 did not go far enough to allow gcov+tsan to cooperate. With this
commit it's possible to run the following code without false positives:

  std::thread T1(fib), T2(fib);
  T1.join(); T2.join();

llvm-svn: 276015

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index dcb62d3..41041c7 100644
--- a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -272,8 +272,9 @@ static bool shouldInstrumentReadWriteFromAddress(Value *Addr) {
         return false;
     }
 
-    // Check if the global is in a GCOV counter array.
-    if (GV->getName().startswith("__llvm_gcov_ctr"))
+    // Check if the global is private gcov data.
+    if (GV->getName().startswith("__llvm_gcov") ||
+        GV->getName().startswith("__llvm_gcda"))
       return false;
   }