[C++11] Add 'override' keyword to virtual methods that override their base class.

llvm-svn: 203220
diff --git a/llvm/lib/CodeGen/MachineCopyPropagation.cpp b/llvm/lib/CodeGen/MachineCopyPropagation.cpp
index e41d3ee..7c981ca 100644
--- a/llvm/lib/CodeGen/MachineCopyPropagation.cpp
+++ b/llvm/lib/CodeGen/MachineCopyPropagation.cpp
@@ -42,7 +42,7 @@
      initializeMachineCopyPropagationPass(*PassRegistry::getPassRegistry());
     }
 
-    virtual bool runOnMachineFunction(MachineFunction &MF);
+    bool runOnMachineFunction(MachineFunction &MF) override;
 
   private:
     typedef SmallVector<unsigned, 4> DestList;