[tsan] Try harder to not instrument gcov counters

GCOVProfiler::emitProfileArcs() can create many variables with names
starting with "__llvm_gcov_ctr", so llvm appends a numeric suffix to
most of them. Teach tsan about this.

llvm-svn: 274801

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index a23b1ddf825..dcb62d3ed1b 100644
--- a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -272,8 +272,8 @@ static bool shouldInstrumentReadWriteFromAddress(Value *Addr) {
         return false;
     }
 
-    // Check if the global is in the GCOV counters array.
-    if (GV->getName() == "__llvm_gcov_ctr")
+    // Check if the global is in a GCOV counter array.
+    if (GV->getName().startswith("__llvm_gcov_ctr"))
       return false;
   }