[LLVMdev] TableGen: RegisterClass question

[Vladimir Prus]

Hi,
I'm porting some existing code of mine to CVS HEAD, and don't understand
something about new RegisterClass TableGen definition:

    class RegisterClass<string namespace, list<ValueType> regTypes,........
    {
       .....
       string Namespace = namespace;

What is this "namespace" thing? It looks like it should contain the name of
backend, right? 

  // RegType - Specify the ValueType of the registers in this register
  // class. Note that all registers in a register class must have the same
  // ValueType.
  list<ValueType> RegTypes = regTypes;

The comment seems out of date -- it says that only one type is allowed,
while list is used. Can somebody explain what would it mean for a register
class to have several allowed ValueTypes?

Thanks,
Volodya