alloc_ref_dynamic allocates an instance of a class type based on the
value in its metatype operand. Start emitting these instructions for
the allocating constructor of a complete object initializer (not yet
tested) and for the allocating constructor synthesized for an imported
Objective-C init method.
Still missing:
- IRGen still does the same thing as alloc_ref right now. That
change will follow.
- There are devirtualization opportunities when we know the value of
the metatype that would turn an alloc_ref_dynamic into an alloc_ref;
I'm not planning to do this optimization.
Swift SVN r14560
With this commit, we can deserialize the stdlib. Still running into
issues related to linking that requires a consultation with John. That
will come in a later commit.
Swift SVN r14365
