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

llvm-svn: 203345
diff --git a/llvm/tools/llvm-mc/Disassembler.cpp b/llvm/tools/llvm-mc/Disassembler.cpp
index 509a1d4..9c402f2 100644
--- a/llvm/tools/llvm-mc/Disassembler.cpp
+++ b/llvm/tools/llvm-mc/Disassembler.cpp
@@ -35,10 +35,10 @@
 public:
   VectorMemoryObject(const ByteArrayTy &bytes) : Bytes(bytes) {}
 
-  uint64_t getBase() const { return 0; }
-  uint64_t getExtent() const { return Bytes.size(); }
+  uint64_t getBase() const override { return 0; }
+  uint64_t getExtent() const override { return Bytes.size(); }
 
-  int readByte(uint64_t Addr, uint8_t *Byte) const {
+  int readByte(uint64_t Addr, uint8_t *Byte) const override {
     if (Addr >= getExtent())
       return -1;
     *Byte = Bytes[Addr].first;