This is in prepatation for splitting getAtUncurryLevel into one function that
returns the CalleeTypeInfo (which is needed early) and a later one that returns
a ManagedValue, which can occur later.
rdar://33358110
This structure contains all of the type information that we use to build a
ResultPlanPtr. In a subsequent commit, I am going to move ResultPlanPtr creation
out of emitApply and place it before the creation of arguments. This is to
enable indirect result initializations to belong to the scope outside of any
argument based scopes.
Without this the lifetimes of the indirect result initializations and arguments
can not be separated without using hacks. There is no reason why we can't emit
the indirect result temporaries before we emit any arguments since they will
remain dormant until after the final apply/any future committed argument scopes
being popped.
rdar://30955427
