1 files changed, 140 insertions, 0 deletions
diff --git a/src/hir_expand/vtable.cpp b/src/hir_expand/vtable.cpp
new file mode 100644
index 00000000..41869397
--- /dev/null
+++ b/src/hir_expand/vtable.cpp
@@ -0,0 +1,140 @@
+/*
+ * MRustC - Rust Compiler
+ * - By John Hodge (Mutabah/thePowersGang)
+ *
+ * hir_expand/vtable.cpp
+ * - VTable Generation
+ */
+#include "main_bindings.hpp"
+#include <hir/hir.hpp>
+#include <hir/visitor.hpp>
+#include <hir_typeck/common.hpp>    // visit_ty_with
+#include <algorithm>    // ::std::any_of
+
+namespace {
+    class OuterVisitor:
+        public ::HIR::Visitor
+    {
+        //StaticTraitResolve  m_resolve;
+        ::std::function<::HIR::SimplePath(bool, ::std::string, ::HIR::Struct)>  m_new_type;
+        ::HIR::SimplePath   m_lang_Sized;
+    public:
+        OuterVisitor(const ::HIR::Crate& crate)//:
+            //m_resolve(crate)
+        {
+            m_lang_Sized = crate.get_lang_item_path_opt("sized");
+        }
+        
+        void visit_module(::HIR::ItemPath p, ::HIR::Module& mod) override
+        {
+            auto saved_nt = mv$(m_new_type);
+            
+            ::std::vector< decltype(mod.m_mod_items)::value_type> new_types;
+            m_new_type = [&](bool pub, auto name, auto s)->auto {
+                auto boxed = box$( (::HIR::VisEnt< ::HIR::TypeItem> { pub, ::HIR::TypeItem( mv$(s) ) }) );
+                auto ret = (p + name).get_simple_path();
+                new_types.push_back( ::std::make_pair( mv$(name), mv$(boxed)) );
+                return ret;
+                };
+            
+            ::HIR::Visitor::visit_module(p, mod);
+            for(auto& i : new_types )
+                mod.m_mod_items.insert( mv$(i) );
+            
+            m_new_type = mv$(saved_nt);
+        }
+        
+        void visit_trait(::HIR::ItemPath p, ::HIR::Trait& tr) override
+        {
+            TRACE_FUNCTION_F(p);
+            
+            ::HIR::t_struct_fields fields;
+            for(const auto& vi : tr.m_values)
+            {
+                TU_MATCHA( (vi.second), (ve),
+                (Function,
+                    if( ve.m_receiver == ::HIR::Function::Receiver::Free ) {
+                        DEBUG("- '" << vi.first << "' Skip free function");  // ?
+                        continue ;
+                    }
+                    if( ::std::any_of(ve.m_params.m_bounds.begin(), ve.m_params.m_bounds.end(), [&](const auto& b){
+                        return b.is_TraitBound() && b.as_TraitBound().type == ::HIR::TypeRef("Self", 0xFFFF) && b.as_TraitBound().trait.m_path.m_path == m_lang_Sized;
+                        }) )
+                    {
+                        DEBUG("- '" << vi.first << "' Skip where `Self: Sized`");
+                        continue ;
+                    }
+                    if( ve.m_params.m_types.size() > 0 ) {
+                        DEBUG("- '" << vi.first << "' NOT object safe (generic), not creating vtable");
+                        return ;
+                    }
+                    
+                    ::HIR::FunctionType ft;
+                    ft.is_unsafe = ve.m_unsafe;
+                    ft.m_abi = ve.m_abi;
+                    ft.m_rettype = box$( ve.m_return.clone() );
+                    for(const auto& t : ve.m_args)
+                        ft.m_arg_types.push_back( t.second.clone() );
+                    ft.m_arg_types[0] = ::HIR::TypeRef();   // Clear the first argument (the receiver)
+                    ::HIR::TypeRef  fcn_type( mv$(ft) );
+                    
+                    // Detect use of `Self`
+                    if( visit_ty_with(fcn_type, [&](const auto& t){
+                        if( t == ::HIR::TypeRef("Self", 0xFFFF) )
+                            return true;
+                        return false;
+                        })
+                        )
+                    {
+                        DEBUG("- '" << vi.first << "' NOT object safe (Self), not creating vtable");
+                        return ;
+                    }
+                    
+                    fields.push_back( ::std::make_pair(
+                        vi.first,
+                        ::HIR::VisEnt< ::HIR::TypeRef> { true, mv$(fcn_type) }
+                        ) );
+                    ),
+                (Static,
+                    TODO(Span(), "Associated static in vtable");
+                    ),
+                (Constant,
+                    //TODO(Span(), "Associated const in vtable");
+                    )
+                )
+            }
+            
+            ::HIR::PathParams   params;
+            ::HIR::GenericParams    args;
+            // TODO: Would like to have access to the publicity marker
+            auto item_path = m_new_type(true, FMT(p.get_name() << "#vtable"), ::HIR::Struct {
+                mv$(args),
+                ::HIR::Struct::Repr::Rust,
+                ::HIR::Struct::Data(mv$(fields)),
+                {}
+                });
+            DEBUG("Vtable structure created - " << item_path);
+            ::HIR::GenericPath  path( mv$(item_path), mv$(params) );
+            
+            tr.m_values.insert( ::std::make_pair(
+                "#vtable",
+                ::HIR::TraitValueItem(::HIR::Static { false, ::HIR::TypeRef( mv$(path) ), {},{} })
+                ) );
+        }
+        
+        void visit_trait_impl(const ::HIR::SimplePath& trait_path, ::HIR::TraitImpl& impl) override
+        {
+            TRACE_FUNCTION_F("impl " << trait_path << " for " << impl.m_type);
+            //auto _ = this->m_resolve.set_impl_generics(impl.m_params);
+            
+            ::HIR::Visitor::visit_trait_impl(trait_path, impl);
+        }
+    };
+}
+
+void HIR_Expand_VTables(::HIR::Crate& crate)
+{
+    OuterVisitor    ov(crate);
+    ov.visit_crate( crate );
+}
+