Merge #1583

1583: Support type resolution on super traits on dyn objects r=philberty a=philberty

When checking if specified bounds satisfy other bounds we must lookup the super traits. To finish the support for super traits we need to redo the computation of method addresses to support super traits.

Addresses #914


Co-authored-by: Philip Herron <philip.herron@embecosm.com>

3 files changed, 37 insertions, 24 deletions

diff --git a/gcc/rust/backend/rust-compile.cc b/gcc/rust/backend/rust-compile.cc
index 0ccb98d..0c72a16 100644
--- a/gcc/rust/backend/rust-compile.cc
+++ b/gcc/rust/backend/rust-compile.cc
@@ -247,6 +247,8 @@ HIRCompileBase::compute_address_for_trait_item (
   // Algo:
   // check if there is an impl-item for this trait-item-ref first
   // else assert that the trait-item-ref has an implementation
+  //
+  // FIXME this does not support super traits
 
   TyTy::TypeBoundPredicateItem predicate_item
     = predicate->lookup_associated_item (ref->get_identifier ());
diff --git a/gcc/rust/typecheck/rust-hir-trait-ref.h b/gcc/rust/typecheck/rust-hir-trait-ref.h
index 0f4883d..d0814f6 100644
--- a/gcc/rust/typecheck/rust-hir-trait-ref.h
+++ b/gcc/rust/typecheck/rust-hir-trait-ref.h
@@ -380,6 +380,16 @@ public:
     return item_refs;
   }
 
+  void get_trait_items_and_supers (
+    std::vector<const TraitItemReference *> &result) const
+  {
+    for (const auto &item : item_refs)
+      result.push_back (&item);
+
+    for (const auto &super_trait : super_traits)
+      super_trait->get_trait_items_and_supers (result);
+  }
+
   void on_resolved ()
   {
     for (auto &item : item_refs)
@@ -451,6 +461,20 @@ public:
     return trait_substs;
   }
 
+  bool satisfies_bound (const TraitReference &reference) const
+  {
+    if (is_equal (reference))
+      return true;
+
+    for (const auto &super_trait : super_traits)
+      {
+	if (super_trait->satisfies_bound (reference))
+	  return true;
+      }
+
+    return false;
+  }
+
 private:
   const HIR::Trait *hir_trait_ref;
   std::vector<TraitItemReference> item_refs;
diff --git a/gcc/rust/typecheck/rust-tyty.cc b/gcc/rust/typecheck/rust-tyty.cc
index b9a9318..65b9f81 100644
--- a/gcc/rust/typecheck/rust-tyty.cc
+++ b/gcc/rust/typecheck/rust-tyty.cc
@@ -136,22 +136,18 @@ bool
 BaseType::satisfies_bound (const TypeBoundPredicate &predicate) const
 {
   const Resolver::TraitReference *query = predicate.get ();
-  for (auto &bound : specified_bounds)
+  for (const auto &bound : specified_bounds)
     {
       const Resolver::TraitReference *item = bound.get ();
-      bool found = item->get_mappings ().get_defid ()
-		   == query->get_mappings ().get_defid ();
-      if (found)
+      if (item->satisfies_bound (*query))
 	return true;
     }
 
   auto probed = Resolver::TypeBoundsProbe::Probe (this);
-  for (auto &b : probed)
+  for (const auto &b : probed)
     {
       const Resolver::TraitReference *bound = b.first;
-      bool found = bound->get_mappings ().get_defid ()
-		   == query->get_mappings ().get_defid ();
-      if (found)
+      if (bound->satisfies_bound (*query))
 	return true;
     }
 
@@ -191,7 +187,6 @@ BaseType::bounds_compatible (const BaseType &other, Location locus,
 	  rust_error_at (r,
 			 "bounds not satisfied for %s %<%s%> is not satisfied",
 			 other.get_name ().c_str (), missing_preds.c_str ());
-	  // rust_assert (!emit_error);
 	}
     }
 
@@ -2956,23 +2951,15 @@ DynamicObjectType::get_object_items () const
   for (auto &bound : get_specified_bounds ())
     {
       const Resolver::TraitReference *trait = bound.get ();
-      for (auto &item : trait->get_trait_items ())
-	{
-	  if (item.get_trait_item_type ()
-		== Resolver::TraitItemReference::TraitItemType::FN
-	      && item.is_object_safe ())
-	    items.push_back ({&item, &bound});
-	}
+      std::vector<const Resolver::TraitItemReference *> trait_items;
+      trait->get_trait_items_and_supers (trait_items);
 
-      for (auto &super_trait : trait->get_super_traits ())
+      for (auto &item : trait_items)
 	{
-	  for (auto &item : super_trait->get_trait_items ())
-	    {
-	      if (item.get_trait_item_type ()
-		    == Resolver::TraitItemReference::TraitItemType::FN
-		  && item.is_object_safe ())
-		items.push_back ({&item, &bound});
-	    }
+	  if (item->get_trait_item_type ()
+		== Resolver::TraitItemReference::TraitItemType::FN
+	      && item->is_object_safe ())
+	    items.push_back ({item, &bound});
 	}
     }
   return items;