Build a nominal type descriptor when we emit the metadata or generic metadata pattern for a nominal type, and put a reference into the formerly null slot in the struct or enum metadata. We need to make a place for them in class metadata; that'll come next.
Swift SVN r9492
In the fill function for a generic struct metadata template, gather metadata for all of the field types, then invoke the runtime's new initStructMetadata function to initialize the field offset vector and vwtable.
Swift SVN r9123
When we have fixed offsets available for fields, emit them into the metadata or metadata pattern. If we don't, emit zero and leave it for the pattern fill function to resolve at runtime.
Swift SVN r9114
of a class is part of the class members section and is not
global to the entire class metadata. This is crucial for
correct operation of functions expecting a base-class
metadata object.
That gives us the correct foundation to implement an
optimization under which generic arguments that can be
inferred from the 'this' pointer need not actually be
separately passed. This has the important result of
making all class member functions with the same signature
up to abstraction actually have the same physical
signature.
Swift SVN r2936
