Fix interface types and type lowering of DynamicSelf so archetypes don't creep in.

Allows us to invoke DynamicSelf methods of generic classes.


Swift SVN r13290

include/swift/AST/Decl.h

@@ -3126,6 +3126,11 @@ public:
   /// this method does not have a \c DynamicSelf return type.
   DynamicSelfType *getDynamicSelf() const;
 
+  /// Retrieve the \c DynamicSelf interface type for this method, or a
+  /// null type if this method does not have a \c DynamicSelf return
+  /// type.
+  DynamicSelfType *getDynamicSelfInterface() const;
+
   /// Given that this is an Objective-C method declaration, produce
   /// its selector in the given buffer (as UTF-8).
   StringRef getObjCSelector(SmallVectorImpl<char> &buffer) const;

lib/AST/ASTContext.cpp

@@ -134,6 +134,7 @@ struct ASTContext::Implementation {
     llvm::DenseMap<std::pair<Type, Type>, SubstitutedType *> SubstitutedTypes;
     llvm::DenseMap<std::pair<Type, void*>, DependentMemberType *>
       DependentMemberTypes;
+    llvm::DenseMap<Type, DynamicSelfType *> DynamicSelfTypes;
     llvm::FoldingSet<EnumType> EnumTypes;
     llvm::FoldingSet<StructType> StructTypes;
     llvm::FoldingSet<ClassType> ClassTypes;
@@ -170,7 +171,6 @@ struct ASTContext::Implementation {
   llvm::FoldingSet<ProtocolCompositionType> ProtocolCompositionTypes;
   llvm::FoldingSet<BuiltinVectorType> BuiltinVectorTypes;
   llvm::FoldingSet<GenericSignature> GenericSignatures;
-  llvm::DenseMap<Type, DynamicSelfType *> DynamicSelfTypes;
   
   /// \brief The permanent arena.
   Arena Permanent;
@@ -1370,18 +1370,17 @@ ModuleType *ModuleType::get(Module *M) {
 }
 
 DynamicSelfType *DynamicSelfType::get(Type selfType, const ASTContext &ctx) {
-  assert(!selfType->hasTypeVariable() && "Type variable in DynamicSelfType");
-  
-  auto known = ctx.Impl.DynamicSelfTypes.find(selfType);
-  if (known != ctx.Impl.DynamicSelfTypes.end())
-    return known->second;
-
   auto properties = selfType->getRecursiveProperties()
                     - RecursiveTypeProperties::IsNotMaterializable;
-  auto arena = getArena(properties);  
+  auto arena = getArena(properties);
+
+  auto &dynamicSelfTypes = ctx.Impl.getArena(arena).DynamicSelfTypes;
+  auto known = dynamicSelfTypes.find(selfType);
+  if (known != dynamicSelfTypes.end())
+    return known->second;
 
   auto result = new (ctx, arena) DynamicSelfType(selfType, ctx, properties);
-  ctx.Impl.DynamicSelfTypes.insert({selfType, result});
+  dynamicSelfTypes.insert({selfType, result});
   return result;
 }
 

lib/AST/Decl.cpp

@@ -1569,6 +1569,14 @@ DynamicSelfType *FuncDecl::getDynamicSelf() const {
   return DynamicSelfType::get(getExtensionType(), getASTContext());
 }
 
+DynamicSelfType *FuncDecl::getDynamicSelfInterface() const {
+  if (!hasDynamicSelf())
+    return nullptr;
+
+  return DynamicSelfType::get(getDeclContext()->getDeclaredInterfaceType(), 
+                              getASTContext());
+}
+
 StringRef VarDecl::getObjCGetterSelector(SmallVectorImpl<char> &buffer) const {
   llvm::raw_svector_ostream out(buffer);
 

lib/SIL/TypeLowering.cpp

@@ -976,7 +976,8 @@ namespace {
     }
 
     const TypeLowering *visitDynamicSelfType(CanDynamicSelfType type) {
-      return LowerType(TC, type.getSelfType(), Dependent)
+      return LowerType(TC, cast<DynamicSelfType>(OrigType).getSelfType(), 
+                       Dependent)
                .visit(type.getSelfType());
     }
 

lib/Sema/TypeCheckGeneric.cpp

@@ -652,6 +652,8 @@ bool TypeChecker::validateGenericFuncSignature(AbstractFunctionDecl *func) {
     funcTy = fn->getBodyResultTypeLoc().getType();
     if (!funcTy) {
       funcTy = TupleType::getEmpty(Context);
+    } else if (funcTy->is<DynamicSelfType>()) {
+      funcTy = fn->getDynamicSelfInterface();
     }
   } else if (auto ctor = dyn_cast<ConstructorDecl>(func)) {
     funcTy = ctor->getExtensionType()->getAnyNominal()