Eliminate all but one top-level class per library.

runtime/vm/parser.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/parser.h"
 #include "vm/flags.h"
 
 #ifndef DART_PRECOMPILED
 
 #include "lib/invocation_mirror.h"
@@ skipping 989 matching lines @@
       instantiator = parser.LookupReceiver(node_sequence->scope(), kTestOnly);
     }
     if (!parser.current_function().IsLocalFunction() ||
         ((instantiator != NULL) && instantiator->is_captured())) {
       parsed_function->set_instantiator(instantiator);
     }
   }
 }
 
 
-RawObject* Parser::ParseMetadata(const Class& cls, intptr_t token_pos) {
+RawObject* Parser::ParseMetadata(const Field& meta_data) {
   Thread* thread = Thread::Current();
   Isolate* isolate = thread->isolate();
   StackZone stack_zone(thread);
   Zone* zone = stack_zone.GetZone();
   LongJumpScope jump;
+
+  const Class& owner_class = Class::Handle(zone, meta_data.owner());
+  const Script& script = Script::Handle(zone, meta_data.script());
+  const intptr_t token_pos = meta_data.token_pos();
+
   if (setjmp(*jump.Set()) == 0) {
-    const Script& script = Script::Handle(zone, cls.script());
     // Parsing metadata can involve following paths in the parser that are
     // normally used for expressions and assume current_function is non-null,
     // so we create a fake function to use as the current_function rather than
     // scattering special cases throughout the parser.
     const Function& fake_function = Function::ZoneHandle(zone, Function::New(
         Symbols::At(),
         RawFunction::kRegularFunction,
         true,  // is_static
         false,  // is_const
         false,  // is_abstract
         false,  // is_external
         false,  // is_native
-        cls,
+        Object::Handle(zone, meta_data.RawOwner()),
         token_pos));
     fake_function.set_is_debuggable(false);
     ParsedFunction* parsed_function =
         new ParsedFunction(thread, fake_function);
     Parser parser(script, parsed_function, token_pos);
-    parser.set_current_class(cls);
+    parser.set_current_class(owner_class);
 
     RawObject* metadata = parser.EvaluateMetadata();
     return metadata;
   } else {
     Error& error = Error::Handle(zone);
     error = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
     return error.raw();
   }
   UNREACHABLE();
@@ skipping 91 matching lines @@
   return CloseBlock();
 }
 
 
 ParsedFunction* Parser::ParseStaticFieldInitializer(const Field& field) {
   ASSERT(field.is_static());
   Thread* thread = Thread::Current();
   // TODO(koda): Should there be a StackZone here?
   Zone* zone = thread->zone();
 
-  const Class& script_cls = Class::Handle(zone, field.origin());
-  const Script& script = Script::Handle(zone, script_cls.script());
-
   const String& field_name = String::Handle(zone, field.name());
   String& init_name = String::Handle(zone,
       Symbols::FromConcat(Symbols::InitPrefix(), field_name));
 
+  const Script& script = Script::Handle(zone, field.script());
   Object& initializer_owner = Object::Handle(field.owner());
-  if (field.owner() != field.origin()) {
-    initializer_owner =
-        PatchClass::New(Class::Handle(field.owner()), script_cls);
-  }
+  initializer_owner =
+      PatchClass::New(Class::Handle(field.owner()), script);
 
   const Function& initializer = Function::ZoneHandle(zone,
       Function::New(init_name,
                     RawFunction::kImplicitStaticFinalGetter,
                     true,   // static
                     false,  // !const
                     false,  // !abstract
                     false,  // !external
                     false,  // !native
                     initializer_owner,
@@ skipping 670 matching lines @@
 
       // Add implicit closure object parameter.
       func_params.AddFinalParameter(
           TokenPos(),
           &Symbols::ClosureParameter(),
           &Type::ZoneHandle(Z, Type::DynamicType()));
 
       const bool no_explicit_default_values = false;
       ParseFormalParameterList(no_explicit_default_values, false, &func_params);
 
+      // In top-level and mixin functions, the source may be in a different
+      // script than the script of the current class.
+      Object& sig_func_owner = Object::Handle(Z, current_class().raw());
+      if (current_class().script() != script_.raw()) {
+        sig_func_owner = PatchClass::New(current_class(), script_);

[Ivan Posva, 2015/11/30 23:54:26]

If the current_class().script and script_.raw() are not the same, should we not
reuse the PatchClass object that was used to setup this disparity?

[hausner, 2015/12/01 19:38:17]

Yes. But unless I add the RawOwner to the Parser class, we don't have access to
it here. This code can be called before the Function object (whose parameters we
are parsing) exists. Thus, I can't 'steal' the owner from it.

We only get to this code when we parse a function type that is 'inlined'
directly in the signature of a function. I don't expect that to be common. Most
code would use a typedef for that. Thus, I thought we can get away with
allocating a patch class in this rare case.

+      }
+
       // The field 'is_static' has no meaning for signature functions.
       const Function& signature_function = Function::Handle(Z,
           Function::New(*parameter.name,
                         RawFunction::kSignatureFunction,
                         /* is_static = */ false,
                         /* is_const = */ false,
                         /* is_abstract = */ false,
                         /* is_external = */ false,
                         /* is_native = */ false,
-                        current_class(),
+                        sig_func_owner,
                         parameter.name_pos));
       signature_function.set_result_type(result_type);
       signature_function.set_is_debuggable(false);
       AddFormalParamsToFunction(&func_params, signature_function);
-      const String& signature = String::Handle(Z,
-                                               signature_function.Signature());
+      const String& signature =
+          String::Handle(Z, signature_function.Signature());
       // Lookup the signature class, i.e. the class whose name is the signature.
       // We only lookup in the current library, but not in its imports, and only
       // create a new canonical signature class if it does not exist yet.
-      Class& signature_class = Class::ZoneHandle(Z,
-          library_.LookupLocalClass(signature));
+      Class& signature_class =
+          Class::ZoneHandle(Z, library_.LookupLocalClass(signature));
       if (signature_class.IsNull()) {
         signature_class = Class::NewSignatureClass(signature,
                                                    signature_function,
                                                    script_,
                                                    parameter.name_pos);
         // Record the function signature class in the current library, unless
         // we are currently skipping a formal parameter list, in which case
         // the signature class could remain unfinalized.
         if (!params->skipped) {
           library_.AddClass(signature_class);
@@ skipping 2526 matching lines @@
   } else {
     UnexpectedToken();
   }
   current_member_ = NULL;
   CheckMemberNameConflict(members, &member);
   members->AddMember(member);
 }
 
 
 void Parser::ParseEnumDeclaration(const GrowableObjectArray& pending_classes,
-                                  const Class& toplevel_class,
+                                  const PatchClass& tl_owner,
                                   intptr_t metadata_pos) {
   TRACE_PARSER("ParseEnumDeclaration");
   const intptr_t declaration_pos = (metadata_pos > 0) ? metadata_pos
                                                       : TokenPos();
   ConsumeToken();
   const intptr_t name_pos = TokenPos();
   String* enum_name =
       ExpectUserDefinedTypeIdentifier("enum type name expected");
   if (FLAG_trace_parser) {
     OS::Print("TopLevel parsing enum '%s'\n", enum_name->ToCString());
@@ skipping 21 matching lines @@
   if (!obj.IsNull()) {
     ReportError(name_pos, "'%s' is already defined", enum_name->ToCString());
   }
   Class& cls = Class::Handle(Z);
   cls = Class::New(*enum_name, script_, declaration_pos);
   cls.set_library(library_);
   library_.AddClass(cls);
   cls.set_is_synthesized_class();
   cls.set_is_enum_class();
   if (metadata_pos >= 0) {
-    library_.AddClassMetadata(cls, toplevel_class, metadata_pos);
+    library_.AddClassMetadata(cls, tl_owner, metadata_pos);
   }
   cls.set_super_type(Type::Handle(Z, Type::ObjectType()));
   pending_classes.Add(cls, Heap::kOld);
 }
 
 
 void Parser::ParseClassDeclaration(const GrowableObjectArray& pending_classes,
-                                   const Class& toplevel_class,
+                                   const PatchClass& tl_owner,
                                    intptr_t metadata_pos) {
   TRACE_PARSER("ParseClassDeclaration");
   bool is_patch = false;
   bool is_abstract = false;
   intptr_t declaration_pos = (metadata_pos > 0) ? metadata_pos : TokenPos();
   if (is_patch_source() &&
       (CurrentToken() == Token::kIDENT) &&
       CurrentLiteral()->Equals("patch")) {
     ConsumeToken();
     is_patch = true;
@@ skipping 94 matching lines @@
                     String::Handle(orig_bound.UserVisibleName()).ToCString());
       }
     }
     cls.set_type_parameters(orig_type_parameters);
   }
 
   if (is_abstract) {
     cls.set_is_abstract();
   }
   if (metadata_pos >= 0) {
-    library_.AddClassMetadata(cls, toplevel_class, metadata_pos);
+    library_.AddClassMetadata(cls, tl_owner, metadata_pos);
   }
 
   const bool is_mixin_declaration = (CurrentToken() == Token::kASSIGN);
   if (is_mixin_declaration && is_patch) {
     ReportError(classname_pos,
                 "mixin application '%s' may not be a patch class",
                 class_name.ToCString());
   }
 
   AbstractType& super_type = Type::Handle(Z);
@@ skipping 359 matching lines @@
       // compiled.
       ctors.Add(member);
       member = class_desc->LookupMember(*member->redirect_name);
     }
   }
 }
 
 
 void Parser::ParseMixinAppAlias(
     const GrowableObjectArray& pending_classes,
-    const Class& toplevel_class,
+    const PatchClass& tl_owner,
     intptr_t metadata_pos) {
   TRACE_PARSER("ParseMixinAppAlias");
   const intptr_t classname_pos = TokenPos();
   String& class_name = *ExpectUserDefinedTypeIdentifier("class name expected");
   if (FLAG_trace_parser) {
     OS::Print("toplevel parsing mixin application alias class '%s'\n",
               class_name.ToCString());
   }
   const Object& obj = Object::Handle(Z, library_.LookupLocalObject(class_name));
   if (!obj.IsNull()) {
@@ skipping 33 matching lines @@
 
   // This mixin application alias needs an implicit constructor, but it is
   // too early to call 'AddImplicitConstructor(mixin_application)' here,
   // because this class should be lazily compiled.
   if (CurrentToken() == Token::kIMPLEMENTS) {
     ParseInterfaceList(mixin_application);
   }
   ExpectSemicolon();
   pending_classes.Add(mixin_application, Heap::kOld);
   if (metadata_pos >= 0) {
-    library_.AddClassMetadata(mixin_application, toplevel_class, metadata_pos);
+    library_.AddClassMetadata(mixin_application, tl_owner, metadata_pos);
   }
 }
 
 
 // Look ahead to detect if we are seeing ident [ TypeParameters ] "(".
 // We need this lookahead to distinguish between the optional return type
 // and the alias name of a function type alias.
 // Token position remains unchanged.
 bool Parser::IsFunctionTypeAliasName() {
   if (IsIdentifier() && (LookaheadToken(1) == Token::kLPAREN)) {
@@ skipping 25 matching lines @@
     if (TryParseTypeParameters() && (CurrentToken() == Token::kASSIGN)) {
       is_mixin_def = true;
     }
   }
   SetPosition(saved_pos);
   return is_mixin_def;
 }
 
 
 void Parser::ParseTypedef(const GrowableObjectArray& pending_classes,
-                          const Class& toplevel_class,
+                          const PatchClass& tl_owner,
                           intptr_t metadata_pos) {
   TRACE_PARSER("ParseTypedef");
   intptr_t declaration_pos = (metadata_pos > 0) ? metadata_pos : TokenPos();
   ExpectToken(Token::kTYPEDEF);
 
   if (IsMixinAppAlias()) {
     if (FLAG_warn_mixin_typedef) {
       ReportWarning(TokenPos(), "deprecated mixin application typedef");
     }
-    ParseMixinAppAlias(pending_classes, toplevel_class, metadata_pos);
+    ParseMixinAppAlias(pending_classes, tl_owner, metadata_pos);
     return;
   }
 
   // Parse the result type of the function type.
   AbstractType& result_type = Type::Handle(Z, Type::DynamicType());
   if (CurrentToken() == Token::kVOID) {
     ConsumeToken();
     result_type = Type::VoidType();
   } else if (!IsFunctionTypeAliasName()) {
     // Type annotations in typedef are never ignored, even in production mode.
@@ skipping 90 matching lines @@
   }
   ASSERT(signature_function.signature_class() == signature_class.raw());
 
   // The alias should not be marked as finalized yet, since it needs to be
   // checked in the class finalizer for illegal self references.
   ASSERT(!function_type_alias.IsCanonicalSignatureClass());
   ASSERT(!function_type_alias.is_finalized());
   pending_classes.Add(function_type_alias, Heap::kOld);
   if (metadata_pos >= 0) {
     library_.AddClassMetadata(function_type_alias,
-                              toplevel_class,
+                              tl_owner,
                               metadata_pos);
   }
 }
 
 
 // Consumes exactly one right angle bracket. If the current token is a single
 // bracket token, it is consumed normally. However, if it is a double or triple
 // bracket, it is replaced by a single or double bracket token without
 // incrementing the token index.
 void Parser::ConsumeRightAngleBracket() {
@@ skipping 216 matching lines @@
                   String::Handle(Z, mixin_type.UserVisibleName()).ToCString());
     }
     mixin_types.Add(mixin_type);
   } while (CurrentToken() == Token::kCOMMA);
   return MixinAppType::New(super_type,
       Array::Handle(Z, Array::MakeArray(mixin_types)));
 }
 
 
 void Parser::ParseTopLevelVariable(TopLevel* top_level,
+                                   const PatchClass& owner,
                                    intptr_t metadata_pos) {
   TRACE_PARSER("ParseTopLevelVariable");
   const bool is_const = (CurrentToken() == Token::kCONST);
   // Const fields are implicitly final.
   const bool is_final = is_const || (CurrentToken() == Token::kFINAL);
   const bool is_static = true;
   const AbstractType& type = AbstractType::ZoneHandle(Z,
       ParseConstFinalVarOrType(ClassFinalizer::kResolveTypeParameters));
   Field& field = Field::Handle(Z);
   Function& getter = Function::Handle(Z);
@@ skipping 15 matching lines @@
                   var_name.ToCString());
     }
     accessor_name = Field::SetterName(var_name);
     if (library_.LookupLocalObject(accessor_name) != Object::null()) {
       ReportError(name_pos, "setter for '%s' is already defined",
                   var_name.ToCString());
     }
 
     const bool is_reflectable =
         !(library_.is_dart_scheme() && library_.IsPrivate(var_name));
-    field = Field::New(var_name, is_static, is_final, is_const, is_reflectable,
-                       current_class(), type, name_pos);
+
+    field = Field::NewTopLevel(var_name, is_final, is_const, owner, name_pos);
+    field.SetFieldType(type);
+    field.set_is_reflectable(is_reflectable);
     field.SetStaticValue(Object::null_instance(), true);
     top_level->AddField(field);
     library_.AddObject(field, var_name);
     if (metadata_pos >= 0) {
       library_.AddFieldMetadata(field, metadata_pos);
     }
     if (CurrentToken() == Token::kASSIGN) {
       ConsumeToken();
       Instance& field_value = Instance::Handle(Z, Object::sentinel().raw());
       bool has_simple_literal = false;
       if (LookaheadToken(1) == Token::kSEMICOLON) {
         has_simple_literal = IsSimpleLiteral(type, &field_value);
       }
       SkipExpr();
       field.SetStaticValue(field_value, true);
       field.set_has_initializer(true);
 
       if (!has_simple_literal) {
         // Create a static final getter.
         String& getter_name = String::Handle(Z, Field::GetterSymbol(var_name));
         getter = Function::New(getter_name,
                                RawFunction::kImplicitStaticFinalGetter,
                                is_static,
                                is_const,
                                /* is_abstract = */ false,
                                /* is_external = */ false,
                                /* is_native = */ false,
-                               current_class(),
+                               owner,
                                name_pos);
         getter.set_result_type(type);
         getter.set_is_debuggable(false);
-        if (library_.is_dart_scheme() && library_.IsPrivate(var_name)) {
-          getter.set_is_reflectable(false);
-        }
+        getter.set_is_reflectable(is_reflectable);
         top_level->AddFunction(getter);
       }
     } else if (is_final) {
       ReportError(name_pos, "missing initializer for final or const variable");
     }
 
     if (CurrentToken() == Token::kCOMMA) {
       ConsumeToken();
     } else if (CurrentToken() == Token::kSEMICOLON) {
       ConsumeToken();
@@ skipping 26 matching lines @@
     }
     ConsumeToken();
     ConsumeToken();
     return RawFunction::kSyncGen;
   }
   return RawFunction::kNoModifier;
 }
 
 
 void Parser::ParseTopLevelFunction(TopLevel* top_level,
+                                   const PatchClass& owner,
                                    intptr_t metadata_pos) {
   TRACE_PARSER("ParseTopLevelFunction");
   const intptr_t decl_begin_pos = TokenPos();
   AbstractType& result_type = Type::Handle(Z, Type::DynamicType());
   const bool is_static = true;
   bool is_external = false;
   bool is_patch = false;
   if (is_patch_source() &&
       (CurrentToken() == Token::kIDENT) &&
       CurrentLiteral()->Equals("patch") &&
@@ skipping 71 matching lines @@
     ReportError("function block expected");
   }
   Function& func = Function::Handle(Z,
       Function::New(func_name,
                     RawFunction::kRegularFunction,
                     is_static,
                     /* is_const = */ false,
                     /* is_abstract = */ false,
                     is_external,
                     is_native,
-                    current_class(),
+                    owner,
                     decl_begin_pos));
   func.set_result_type(result_type);
   func.set_end_token_pos(function_end_pos);
   func.set_modifier(func_modifier);
   if (library_.is_dart_scheme() && library_.IsPrivate(func_name)) {
     func.set_is_reflectable(false);
   }
   if (is_native) {
     func.set_native_name(*native_name);
   }
   AddFormalParamsToFunction(&params, func);
   top_level->AddFunction(func);
   if (!is_patch) {
     library_.AddObject(func, func_name);
   } else {
+    // Need to remove the previously added function that is being patched.
+    const Class& toplevel_cls = Class::Handle(Z, library_.toplevel_class());
+    const Function& replaced_func =
+        Function::Handle(Z, toplevel_cls.LookupStaticFunction(func_name));
+    ASSERT(!replaced_func.IsNull());
+    toplevel_cls.RemoveFunction(replaced_func);
     library_.ReplaceObject(func, func_name);
   }
   if (metadata_pos >= 0) {
     library_.AddFunctionMetadata(func, metadata_pos);
   }
 }
 
 
 void Parser::ParseTopLevelAccessor(TopLevel* top_level,
+                                   const PatchClass& owner,
                                    intptr_t metadata_pos) {
   TRACE_PARSER("ParseTopLevelAccessor");
   const intptr_t decl_begin_pos = TokenPos();
   const bool is_static = true;
   bool is_external = false;
   bool is_patch = false;
   AbstractType& result_type = AbstractType::Handle(Z);
   if (is_patch_source() &&
       (CurrentToken() == Token::kIDENT) &&
       CurrentLiteral()->Equals("patch")) {
@@ skipping 110 matching lines @@
   }
   Function& func = Function::Handle(Z,
       Function::New(accessor_name,
                     is_getter ? RawFunction::kGetterFunction :
                                 RawFunction::kSetterFunction,
                     is_static,
                     /* is_const = */ false,
                     /* is_abstract = */ false,
                     is_external,
                     is_native,
-                    current_class(),
+                    owner,
                     decl_begin_pos));
   func.set_result_type(result_type);
   func.set_end_token_pos(accessor_end_pos);
   func.set_modifier(func_modifier);
   if (is_native) {
     func.set_is_debuggable(false);
     func.set_native_name(*native_name);
   }
   if (library_.is_dart_scheme() && library_.IsPrivate(accessor_name)) {
     func.set_is_reflectable(false);
   }
   AddFormalParamsToFunction(&params, func);
   top_level->AddFunction(func);
   if (!is_patch) {
     library_.AddObject(func, accessor_name);
   } else {
+    // Need to remove the previously added accessor that is being patched.
+    const Class& toplevel_cls = Class::Handle(Z, owner.patched_class());
+    const Function& replaced_func =
+        Function::Handle(Z, toplevel_cls.LookupFunction(accessor_name));
+    ASSERT(!replaced_func.IsNull());
+    toplevel_cls.RemoveFunction(replaced_func);
     library_.ReplaceObject(func, accessor_name);
   }
   if (metadata_pos >= 0) {
     library_.AddFunctionMetadata(func, metadata_pos);
   }
 }
 
 
 RawObject* Parser::CallLibraryTagHandler(Dart_LibraryTag tag,
                                          intptr_t token_pos,
@@ skipping 59 matching lines @@
     names->Add(*CurrentLiteral());
     ConsumeToken();  // Identifier.
     if (CurrentToken() != Token::kCOMMA) {
       return;
     }
     ConsumeToken();  // Comma.
   }
 }
 
 
-void Parser::ParseLibraryImportExport(intptr_t metadata_pos) {
+void Parser::ParseLibraryImportExport(const PatchClass& tl_owner,
+                                      intptr_t metadata_pos) {
   bool is_import = (CurrentToken() == Token::kIMPORT);
   bool is_export = (CurrentToken() == Token::kEXPORT);
   ASSERT(is_import || is_export);
   const intptr_t import_pos = TokenPos();
   ConsumeToken();
   CheckToken(Token::kSTRING, "library url expected");
   AstNode* url_literal = ParseStringLiteral(false);
   ASSERT(url_literal->IsLiteralNode());
   ASSERT(url_literal->AsLiteralNode()->literal().IsString());
   const String& url = String::Cast(url_literal->AsLiteralNode()->literal());
@@ skipping 64 matching lines @@
   // the library.
   if (library.LoadNotStarted() &&
       (!is_deferred_import || FLAG_load_deferred_eagerly)) {
     library.SetLoadRequested();
     CallLibraryTagHandler(Dart_kImportTag, import_pos, canon_url);
   }
 
   Namespace& ns = Namespace::Handle(Z,
       Namespace::New(library, show_names, hide_names));
   if (metadata_pos >= 0) {
-    ns.AddMetadata(metadata_pos, current_class());
+    ns.AddMetadata(tl_owner, metadata_pos);
   }
 
   // Ensure that private dart:_ libraries are only imported into dart:
   // libraries, including indirectly through exports.
   const String& lib_url = String::Handle(Z, library_.url());
   if (canon_url.StartsWith(Symbols::DartSchemePrivate()) &&
       !lib_url.StartsWith(Symbols::DartScheme())) {
     ReportError(import_pos, "private library is not accessible");
   }
 
@@ skipping 42 matching lines @@
   ASSERT(url_literal->IsLiteralNode());
   ASSERT(url_literal->AsLiteralNode()->literal().IsString());
   const String& url = String::Cast(url_literal->AsLiteralNode()->literal());
   ExpectSemicolon();
   const String& canon_url = String::CheckedHandle(
       CallLibraryTagHandler(Dart_kCanonicalizeUrl, source_pos, url));
   CallLibraryTagHandler(Dart_kSourceTag, source_pos, canon_url);
 }
 
 
-void Parser::ParseLibraryDefinition() {
+void Parser::ParseLibraryDefinition(const PatchClass& tl_owner) {
   TRACE_PARSER("ParseLibraryDefinition");
 
   // Handle the script tag.
   if (CurrentToken() == Token::kSCRIPTTAG) {
     // Nothing to do for script tags except to skip them.
     ConsumeToken();
   }
 
   ASSERT(script_.kind() != RawScript::kSourceTag);
 
   // We may read metadata tokens that are part of the toplevel
   // declaration that follows the library definitions. Therefore, we
   // need to remember the position of the last token that was
   // successfully consumed.
   intptr_t rewind_pos = TokenPos();
   intptr_t metadata_pos = SkipMetadata();
   if (CurrentToken() == Token::kLIBRARY) {
     if (is_patch_source()) {
       ReportError("patch cannot override library name");
     }
     ParseLibraryName();
     if (metadata_pos >= 0) {
-      library_.AddLibraryMetadata(current_class(), metadata_pos);
+      library_.AddLibraryMetadata(tl_owner, metadata_pos);
     }
     rewind_pos = TokenPos();
     metadata_pos = SkipMetadata();
   }
   while ((CurrentToken() == Token::kIMPORT) ||
       (CurrentToken() == Token::kEXPORT)) {
-    ParseLibraryImportExport(metadata_pos);
+    ParseLibraryImportExport(tl_owner, metadata_pos);
     rewind_pos = TokenPos();
     metadata_pos = SkipMetadata();
   }
   // Core lib has not been explicitly imported, so we implicitly
   // import it here.
   if (!library_.ImportsCorelib()) {
     Library& core_lib = Library::Handle(Z, Library::CoreLibrary());
     ASSERT(!core_lib.IsNull());
     const Namespace& core_ns = Namespace::Handle(Z,
         Namespace::New(core_lib, Object::null_array(), Object::null_array()));
@@ skipping 31 matching lines @@
   TRACE_PARSER("ParseTopLevel");
   // Collect the classes found at the top level in this growable array.
   // They need to be registered with class finalization after parsing
   // has been completed.
   ObjectStore* object_store = I->object_store();
   const GrowableObjectArray& pending_classes =
       GrowableObjectArray::Handle(Z, object_store->pending_classes());
   SetPosition(0);
   is_top_level_ = true;
   TopLevel top_level(Z);
-  Class& toplevel_class = Class::Handle(Z,
-      Class::New(Symbols::TopLevel(), script_, TokenPos()));
-  toplevel_class.set_library(library_);
+
+  Class& toplevel_class = Class::Handle(Z, library_.toplevel_class());
+  if (toplevel_class.IsNull()) {
+    toplevel_class = Class::New(Symbols::TopLevel(), script_, TokenPos());
+    toplevel_class.set_library(library_);
+    library_.set_toplevel_class(toplevel_class);

[Ivan Posva, 2015/11/30 23:54:27]

For this compilation unit we can use this top level class and do not need to
allocate a separate patch class. This would be an additional optimization.
Different CL maybe?

[hausner, 2015/12/01 19:38:17]

Done.

+  }
+
+  const PatchClass& tl_owner =
+      PatchClass::ZoneHandle(PatchClass::New(toplevel_class, script_));
 
   if (is_library_source() || is_patch_source()) {
     set_current_class(toplevel_class);
-    ParseLibraryDefinition();
+    ParseLibraryDefinition(tl_owner);
   } else if (is_part_source()) {
     ParsePartHeader();
   }
 
   const Class& cls = Class::Handle(Z);
   while (true) {
     set_current_class(cls);  // No current class.
     intptr_t metadata_pos = SkipMetadata();
     if (CurrentToken() == Token::kCLASS) {
-      ParseClassDeclaration(pending_classes, toplevel_class, metadata_pos);
+      ParseClassDeclaration(pending_classes, tl_owner, metadata_pos);
     } else if (CurrentToken() == Token::kENUM) {
-      ParseEnumDeclaration(pending_classes, toplevel_class, metadata_pos);
+      ParseEnumDeclaration(pending_classes, tl_owner, metadata_pos);
     } else if ((CurrentToken() == Token::kTYPEDEF) &&
                (LookaheadToken(1) != Token::kLPAREN)) {
       set_current_class(toplevel_class);
-      ParseTypedef(pending_classes, toplevel_class, metadata_pos);
+      ParseTypedef(pending_classes, tl_owner, metadata_pos);
     } else if ((CurrentToken() == Token::kABSTRACT) &&
         (LookaheadToken(1) == Token::kCLASS)) {
-      ParseClassDeclaration(pending_classes, toplevel_class, metadata_pos);
+      ParseClassDeclaration(pending_classes, tl_owner, metadata_pos);
     } else if (is_patch_source() && IsSymbol(Symbols::Patch()) &&
                (LookaheadToken(1) == Token::kCLASS)) {
-      ParseClassDeclaration(pending_classes, toplevel_class, metadata_pos);
+      ParseClassDeclaration(pending_classes, tl_owner, metadata_pos);
     } else {
       set_current_class(toplevel_class);
       if (IsVariableDeclaration()) {
-        ParseTopLevelVariable(&top_level, metadata_pos);
+        ParseTopLevelVariable(&top_level, tl_owner, metadata_pos);
       } else if (IsFunctionDeclaration()) {
-        ParseTopLevelFunction(&top_level, metadata_pos);
+        ParseTopLevelFunction(&top_level, tl_owner, metadata_pos);
       } else if (IsTopLevelAccessor()) {
-        ParseTopLevelAccessor(&top_level, metadata_pos);
+        ParseTopLevelAccessor(&top_level, tl_owner, metadata_pos);
       } else if (CurrentToken() == Token::kEOS) {
         break;
       } else {
         UnexpectedToken();
       }
     }
   }
 
-  if ((library_.num_anonymous_classes() == 0) ||
-      (top_level.fields().length() > 0) ||
-      (top_level.functions().length() > 0)) {
+  if (top_level.fields().length() > 0) {
     toplevel_class.AddFields(top_level.fields());
-    const intptr_t len = top_level.functions().length();
-    const Array& array = Array::Handle(Z, Array::New(len, Heap::kOld));
-    for (intptr_t i = 0; i < len; i++) {
-      array.SetAt(i, *top_level.functions()[i]);
-    }
-    toplevel_class.SetFunctions(array);
-    library_.AddAnonymousClass(toplevel_class);
-    pending_classes.Add(toplevel_class, Heap::kOld);
   }
+  for (intptr_t i = 0; i < top_level.functions().length(); i++) {
+    toplevel_class.AddFunction(*top_level.functions()[i]);
+  }
+  pending_classes.Add(toplevel_class, Heap::kOld);
 }
 
 
 void Parser::ChainNewBlock(LocalScope* outer_scope) {
   Block* block = new(Z) Block(
       current_block_,
       outer_scope,
       new(Z) SequenceNode(TokenPos(), outer_scope));
   current_block_ = block;
 }
@@ skipping 38 matching lines @@
         new(Z) LocalScope(current_block_->scope,
                                   current_block_->scope->function_level() + 1,
                                   0);
   }
   ChainNewBlock(outer_scope);
 }
 
 
 void Parser::OpenAsyncClosure() {
   TRACE_PARSER("OpenAsyncClosure");
-
   async_temp_scope_ = current_block_->scope;
-
   OpenAsyncTryBlock();
 }
 
 
 SequenceNode* Parser::CloseAsyncGeneratorTryBlock(SequenceNode *body) {
   TRACE_PARSER("CloseAsyncGeneratorTryBlock");
   // The generated try-catch-finally that wraps the async generator function
   // body is the outermost try statement.
   ASSERT(try_stack_ != NULL);
   ASSERT(try_stack_->outer_try() == NULL);
@@ skipping 8158 matching lines @@
   UNREACHABLE();
   return Object::null();
 }
 
 
 void Parser::ParseFunction(ParsedFunction* parsed_function) {
   UNREACHABLE();
 }
 
 
-RawObject* Parser::ParseMetadata(const Class& cls, intptr_t token_pos) {
+RawObject* Parser::ParseMetadata(const Field& meta_data) {
   UNREACHABLE();
   return Object::null();
 }
 
 
 ParsedFunction* Parser::ParseStaticFieldInitializer(const Field& field) {
   UNREACHABLE();
   return NULL;
 }
 
 
 ArgumentListNode* Parser::BuildNoSuchMethodArguments(
     intptr_t call_pos,
     const String& function_name,
     const ArgumentListNode& function_args,
     const LocalVariable* temp_for_last_arg,
     bool is_super_invocation) {
   UNREACHABLE();
   return NULL;
 }
 
 }  // namespace dart
 
 #endif  // DART_PRECOMPILED