by abstraction from the concrete return type.
This basically gets generic calls working totally as long
as there's no remapping required.
Swift SVN r2402
method to initialize the members. This doesn't matter so much
for structs (the generated IR is essentially equivalent except for
small structs), but on classes, we don't want to make "new X" generate
code that knows about metadata/destructors/etc for the class X.
Also, make sure classes always have a constructor. (We haven't really
discussed the rules for implicitly declared constructors, so for now,
the rule is just "generate an implicit constructor if there is no
explicit constructor". We'll want to revisit this when we actually
design object construction.)
Swift SVN r2361
pointer TypeInfo more conveniently. Have this class return true for
isSingleRetainablePointer(). Further specialize the implementations
of the value witnesses so that we no longer ever require type-specific
witnesses for reference types.
Swift SVN r1900