IR: Make MDString::getName() private

Hide the fact that `MDString`'s string is stored in `Value::Name` --
that's going to change soon.  Update the only in-tree client that was
using it instead of `Value::getString()`.

Part of PR21532.

llvm-svn: 221951

llvm/include/llvm/IR/Metadata.h

@@ -61,6 +61,11 @@ class MDString : public Value {
   MDString(const MDString &) LLVM_DELETED_FUNCTION;
 
   explicit MDString(LLVMContext &C);
+
+private:
+  /// \brief Shadow Value::getName() to prevent its use.
+  StringRef getName() const { return Value::getName(); }
+
 public:
   static MDString *get(LLVMContext &Context, StringRef Str);
   static MDString *get(LLVMContext &Context, const char *Str) {

llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

@@ -1159,7 +1159,7 @@ private:
       return false;
 
     for (auto H : HintTypes)
-      if (Name->getName().endswith(H.Name))
+      if (Name->getString().endswith(H.Name))
         return true;
     return false;
   }