Initial Dynamic dispatch support

This is the first pass at implementing dynamic dispatch, it creates a
vtable object and trait object to store the vtable and reciever. The
method resolution during type checking acts the same as if it was a
generic type bound method call. This detects this case during code
generation to access the dynamic object appropriately to get the fnptr
and call it with the stored reciever.

Fixes: #197

1 files changed, 13 insertions, 0 deletions

diff --git a/gcc/rust/backend/rust-compile-base.h b/gcc/rust/backend/rust-compile-base.h
index 5a26862..4a81061 100644
--- a/gcc/rust/backend/rust-compile-base.h
+++ b/gcc/rust/backend/rust-compile-base.h
@@ -200,6 +200,19 @@ protected:
 
   bool compile_locals_for_block (Resolver::Rib &rib, Bfunction *fndecl,
 				 std::vector<Bvariable *> &locals);
+
+  Bexpression *coercion_site (Bexpression *compiled_ref, TyTy::BaseType *actual,
+			      TyTy::BaseType *expected, Location locus);
+
+  Bexpression *coerce_to_dyn_object (Bexpression *compiled_ref,
+				     TyTy::BaseType *actual,
+				     TyTy::BaseType *expected,
+				     TyTy::DynamicObjectType *ty,
+				     Location locus);
+
+  Bexpression *
+  compute_address_for_trait_item (const Resolver::TraitItemReference *ref,
+				  TyTy::BaseType *receiver);
 };
 
 } // namespace Compile