Remove the unused 4th operand for DIFile debug info metadata

llvm-svn: 176983
diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 6a15033..1932615 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -531,7 +531,7 @@
 
 /// \brief Verify that the file descriptor is well formed.
 bool DIFile::Verify() const {
-  return isFile() && DbgNode->getNumOperands() == 4;
+  return isFile() && DbgNode->getNumOperands() == 3;
 }
 
 /// \brief Verify that the enumerator descriptor is well formed.