+ static MDNode *getIfExists(LLVMContext &Context, ArrayRef<Value*> Vals);
+
+ /// getTemporary - Return a temporary MDNode, for use in constructing
+ /// cyclic MDNode structures. A temporary MDNode is not uniqued,
+ /// may be RAUW'd, and must be manually deleted with deleteTemporary.
+ static MDNode *getTemporary(LLVMContext &Context, ArrayRef<Value*> Vals);
+
+ /// deleteTemporary - Deallocate a node created by getTemporary. The
+ /// node must not have any users.
+ static void deleteTemporary(MDNode *N);
+
+ /// replaceOperandWith - Replace a specific operand.
+ void replaceOperandWith(unsigned i, Value *NewVal);