+ /// FunctionLocalBit - This bit is set if this MDNode is function local.
+ /// This is true when it (potentially transitively) contains a reference to
+ /// something in a function, like an argument, basicblock, or instruction.
+ FunctionLocalBit = 1 << 0,
+
+ /// NotUniquedBit - This is set on MDNodes that are not uniqued because they
+ /// have a null operand.
+ NotUniquedBit = 1 << 1,
+
+ /// DestroyFlag - This bit is set by destroy() so the destructor can assert
+ /// that the node isn't being destroyed with a plain 'delete'.
+ DestroyFlag = 1 << 2