Move class/member computation from CodegenEnqueuer to CodegenWorldBuilder.

pkg/compiler/lib/src/js_backend/enqueuer.dart

Index: pkg/compiler/lib/src/js_backend/enqueuer.dart
diff --git a/pkg/compiler/lib/src/js_backend/enqueuer.dart b/pkg/compiler/lib/src/js_backend/enqueuer.dart
index 4784df02cf69b31160c2a68d7a8e4d8efb5820ac..673d186adcd58f3a2c891b9e6ca9d5883fa5a7e3 100644
--- a/pkg/compiler/lib/src/js_backend/enqueuer.dart
+++ b/pkg/compiler/lib/src/js_backend/enqueuer.dart
@@ -9,49 +9,34 @@ import 'dart:collection' show Queue;
 import '../cache_strategy.dart' show CacheStrategy;
 import '../common/backend_api.dart' show Backend;
 import '../common/codegen.dart' show CodegenWorkItem;
-import '../common/names.dart' show Identifiers;
 import '../common/tasks.dart' show CompilerTask;
 import '../common/work.dart' show WorkItem;
 import '../common.dart';
 import '../compiler.dart' show Compiler;
 import '../dart_types.dart' show DartType, InterfaceType;
-import '../dump_info.dart';
 import '../elements/elements.dart'
-    show
-        ClassElement,
-        Element,
-        Entity,
-        FunctionElement,
-        MemberElement,
-        MethodElement,
-        TypedElement;
+    show ClassElement, Element, Entity, MemberElement, TypedElement;
 import '../elements/entities.dart';
 import '../enqueue.dart';
 import '../js/js.dart' as js;
 import '../native/native.dart' as native;
 import '../options.dart';
 import '../types/types.dart' show TypeMaskStrategy;
-import '../universe/selector.dart' show Selector;
 import '../universe/world_builder.dart';
 import '../universe/use.dart'
     show DynamicUse, StaticUse, StaticUseKind, TypeUse, TypeUseKind;
 import '../universe/world_impact.dart'
     show ImpactUseCase, WorldImpact, WorldImpactVisitor;
+import '../util/enumset.dart';
 import '../util/util.dart' show Setlet;
-import '../world.dart';
 
 /// [Enqueuer] which is specific to code generation.
 class CodegenEnqueuer extends EnqueuerImpl {
   final String name;
   final EnqueuerStrategy strategy;
-  final Map<String, Set<Element>> _instanceMembersByName =
-      new Map<String, Set<Element>>();
-  final Map<String, Set<Element>> _instanceFunctionsByName =
-      new Map<String, Set<Element>>();
-  final Set<ClassElement> _processedClasses = new Set<ClassElement>();
+
   Set<ClassElement> _recentClasses = new Setlet<ClassElement>();
-  final CodegenWorldBuilderImpl _universe =
-      new CodegenWorldBuilderImpl(const TypeMaskStrategy());
+  final CodegenWorldBuilderImpl _universe;
 
   bool queueIsClosed = false;
   final CompilerTask task;
@@ -68,14 +53,14 @@ class CodegenEnqueuer extends EnqueuerImpl {
 
   final Set<DynamicUse> newlySeenSelectors;
 
-  bool _enabledNoSuchMethod = false;
-
   static const ImpactUseCase IMPACT_USE =
       const ImpactUseCase('CodegenEnqueuer');
 
   CodegenEnqueuer(this.task, CacheStrategy cacheStrategy, Backend backend,
       this._options, this.strategy)
-      : newlyEnqueuedElements = cacheStrategy.newSet(),
+      : _universe =
+            new CodegenWorldBuilderImpl(backend, const TypeMaskStrategy()),
+        newlyEnqueuedElements = cacheStrategy.newSet(),
         newlySeenSelectors = cacheStrategy.newSet(),
         nativeEnqueuer = backend.nativeCodegenEnqueuer(),
         this._backend = backend,
@@ -85,10 +70,6 @@ class CodegenEnqueuer extends EnqueuerImpl {
 
   CodegenWorldBuilder get universe => _universe;
 
-  // TODO(johnniwinther): Remove these hacks:
-  ClosedWorld get _world => _backend.compiler.closedWorld;
-  DumpInfoTask get _dumpInfoTask => _backend.compiler.dumpInfoTask;
-
   bool get queueIsEmpty => _queue.isEmpty;
 
   /// Returns [:true:] if this enqueuer is the resolution enqueuer.
@@ -122,9 +103,7 @@ class CodegenEnqueuer extends EnqueuerImpl {
           element, "Codegen work list is closed. Trying to add $element");
     }
     _queue.add(new CodegenWorkItem(_backend, element));
-    // TODO(sigmund): add other missing dependencies (internals, selectors
-    // enqueued after allocations).
-    _dumpInfoTask.registerDependency(element);
+    applyImpact(_backend.registerUsedElement(element, forResolution: false));
   }
 
   void applyImpact(WorldImpact worldImpact, {Element impactSource}) {
@@ -136,22 +115,12 @@ class CodegenEnqueuer extends EnqueuerImpl {
   void _registerInstantiatedType(InterfaceType type,
       {bool mirrorUsage: false, bool nativeUsage: false}) {
     task.measure(() {
-      ClassElement cls = type.element;
-      bool isNative = _backend.isNative(cls);
-      _universe.registerTypeInstantiation(type,
-          isNative: isNative,
-          byMirrors: mirrorUsage, onImplemented: (ClassElement cls) {
-        applyImpact(
-            _backend.registerImplementedClass(cls, forResolution: false));
-      });
+      _universe.registerTypeInstantiation(type, _applyClassUse,
+          byMirrors: mirrorUsage);
       if (nativeUsage) {
         nativeEnqueuer.onInstantiatedType(type);
       }
       _backend.registerInstantiatedType(type);
-      // TODO(johnniwinther): Share this reasoning with [Universe].
-      if (!cls.isAbstract || isNative || mirrorUsage) {
-        _processInstantiatedClass(cls);
-      }
     });
   }
 
@@ -160,224 +129,67 @@ class CodegenEnqueuer extends EnqueuerImpl {
   }
 
   void checkClass(ClassElement cls) {
-    cls.implementation.forEachMember(processInstantiatedClassMember);
-  }
-
-  void processInstantiatedClassMember(ClassElement cls, Element member) {
-    assert(invariant(member, member.isDeclaration));
-    if (isProcessed(member)) return;
-    if (!member.isInstanceMember) return;
-    String memberName = member.name;
-
-    if (member.isField) {
-      // The obvious thing to test here would be "member.isNative",
-      // however, that only works after metadata has been parsed/analyzed,
-      // and that may not have happened yet.
-      // So instead we use the enclosing class, which we know have had
-      // its metadata parsed and analyzed.
-      // Note: this assumes that there are no non-native fields on native
-      // classes, which may not be the case when a native class is subclassed.
-      if (_backend.isNative(cls)) {
-        if (_universe.hasInvokedGetter(member, _world) ||
-            _universe.hasInvocation(member, _world)) {
-          _addToWorkList(member);
-          return;
-        } else if (universe.hasInvokedSetter(member, _world)) {
-          _addToWorkList(member);
-          return;
-        }
-        // Native fields need to go into instanceMembersByName as they
-        // are virtual instantiation points and escape points.
-      } else {
-        // All field initializers must be resolved as they could
-        // have an observable side-effect (and cannot be tree-shaken
-        // away).
-        _addToWorkList(member);
-        return;
-      }
-    } else if (member.isFunction) {
-      FunctionElement function = member;
-      if (function.name == Identifiers.noSuchMethod_) {
-        _registerNoSuchMethod(function);
-      }
-      if (function.name == Identifiers.call && !cls.typeVariables.isEmpty) {
-        _registerCallMethodWithFreeTypeVariables(function);
-      }
-      // If there is a property access with the same name as a method we
-      // need to emit the method.
-      if (_universe.hasInvokedGetter(function, _world)) {
-        _registerClosurizedMember(function);
-        _addToWorkList(function);
-        return;
-      }
-      _registerInstanceMethod(function);
-      if (_universe.hasInvocation(function, _world)) {
-        _addToWorkList(function);
-        return;
-      }
-    } else if (member.isGetter) {
-      FunctionElement getter = member;
-      if (_universe.hasInvokedGetter(getter, _world)) {
-        _addToWorkList(getter);
-        return;
-      }
-      // We don't know what selectors the returned closure accepts. If
-      // the set contains any selector we have to assume that it matches.
-      if (_universe.hasInvocation(getter, _world)) {
-        _addToWorkList(getter);
-        return;
-      }
-    } else if (member.isSetter) {
-      FunctionElement setter = member;
-      if (_universe.hasInvokedSetter(setter, _world)) {
-        _addToWorkList(setter);
-        return;
-      }
-    }
-
-    // The element is not yet used. Add it to the list of instance
-    // members to still be processed.
-    _instanceMembersByName
-        .putIfAbsent(memberName, () => new Set<Element>())
-        .add(member);
-  }
-
-  // Store the member in [instanceFunctionsByName] to catch
-  // getters on the function.
-  void _registerInstanceMethod(MethodElement element) {
-    _instanceFunctionsByName
-        .putIfAbsent(element.name, () => new Set<Element>())
-        .add(element);
-  }
-
-  void _processInstantiatedClass(ClassElement cls) {
-    task.measure(() {
-      if (_processedClasses.contains(cls)) return;
-
-      void processClass(ClassElement superclass) {
-        if (_processedClasses.contains(superclass)) return;
-        // TODO(johnniwinther): Re-insert this invariant when unittests don't
-        // fail. There is already a similar invariant on the members.
-        /*assert(invariant(superclass,
-              superclass.isClosure ||
-              _compiler.enqueuer.resolution.isClassProcessed(superclass),
-              message: "Class $superclass has not been "
-                       "processed in resolution."));
-        */
-
-        _processedClasses.add(superclass);
-        _recentClasses.add(superclass);
-        superclass.implementation.forEachMember(processInstantiatedClassMember);
-        // We only tell the backend once that [superclass] was instantiated, so
-        // any additional dependencies must be treated as global
-        // dependencies.
-        applyImpact(_backend.registerInstantiatedClass(superclass,
-            forResolution: false));
-      }
-
-      ClassElement superclass = cls;
-      while (superclass != null) {
-        processClass(superclass);
-        superclass = superclass.superclass;
-      }
-    });
-  }
-
-  void processDynamicUse(DynamicUse dynamicUse) {
-    task.measure(() {
-      if (_universe.registerDynamicUse(dynamicUse)) {
-        _handleUnseenSelector(dynamicUse);
+    _universe.processClassMembers(cls, (MemberElement member, useSet) {
+      if (useSet.isNotEmpty) {
+        _backend.compiler.reporter.internalError(member,
+            'Unenqueued use of $member: ${useSet.iterable(MemberUse.values)}');
       }
     });
   }
 
-  void _processSet(
-      Map<String, Set<Element>> map, String memberName, bool f(Element e)) {
-    Set<Element> members = map[memberName];
-    if (members == null) return;
-    // [f] might add elements to [: map[memberName] :] during the loop below
-    // so we create a new list for [: map[memberName] :] and prepend the
-    // [remaining] members after the loop.
-    map[memberName] = new Set<Element>();
-    Set<Element> remaining = new Set<Element>();
-    for (Element member in members) {
-      if (!f(member)) remaining.add(member);
+  /// Callback for applying the use of a [cls].
+  void _applyClassUse(ClassEntity cls, EnumSet<ClassUse> useSet) {
+    if (useSet.contains(ClassUse.INSTANTIATED)) {
+      _recentClasses.add(cls);
+      _universe.processClassMembers(cls, _applyMemberUse);
+      // We only tell the backend once that [cls] was instantiated, so
+      // any additional dependencies must be treated as global
+      // dependencies.
+      applyImpact(
+          _backend.registerInstantiatedClass(cls, forResolution: false));
+    }
+    if (useSet.contains(ClassUse.IMPLEMENTED)) {
+      applyImpact(_backend.registerImplementedClass(cls, forResolution: false));
     }
-    map[memberName].addAll(remaining);
-  }
-
-  void _processInstanceMembers(String n, bool f(Element e)) {
-    _processSet(_instanceMembersByName, n, f);
   }
 
-  void _processInstanceFunctions(String n, bool f(Element e)) {
-    _processSet(_instanceFunctionsByName, n, f);
+  /// Callback for applying the use of a [member].
+  void _applyMemberUse(Entity member, EnumSet<MemberUse> useSet) {
+    if (useSet.contains(MemberUse.NORMAL)) {
+      _addToWorkList(member);
+    }
+    if (useSet.contains(MemberUse.CLOSURIZE_INSTANCE)) {
+      _registerClosurizedMember(member);
+    }
+    if (useSet.contains(MemberUse.CLOSURIZE_STATIC)) {
+      applyImpact(_backend.registerGetOfStaticFunction());
+    }
   }
 
-  void _handleUnseenSelector(DynamicUse dynamicUse) {
-    if (_options.hasIncrementalSupport) {
-      newlySeenSelectors.add(dynamicUse);
-    }
-    Selector selector = dynamicUse.selector;
-    String methodName = selector.name;
-    _processInstanceMembers(methodName, (Element member) {
-      if (dynamicUse.appliesUnnamed(member, _world)) {
-        if (member.isFunction && selector.isGetter) {
-          _registerClosurizedMember(member);
+  void processDynamicUse(DynamicUse dynamicUse) {
+    task.measure(() {
+      if (_universe.registerDynamicUse(dynamicUse, _applyMemberUse)) {
+        if (_options.hasIncrementalSupport) {
+          newlySeenSelectors.add(dynamicUse);
         }
-        _addToWorkList(member);
-        return true;
       }
-      return false;
     });
-    if (selector.isGetter) {
-      _processInstanceFunctions(methodName, (Element member) {
-        if (dynamicUse.appliesUnnamed(member, _world)) {
-          _registerClosurizedMember(member);
-          return true;
-        }
-        return false;
-      });
-    }
   }
 
   void processStaticUse(StaticUse staticUse) {
     Element element = staticUse.element;
     assert(invariant(element, element.isDeclaration,
         message: "Element ${element} is not the declaration."));
-    _universe.registerStaticUse(staticUse);
-    applyImpact(_backend.registerUsedElement(element, forResolution: false));
-    bool addElement = true;
+    _universe.registerStaticUse(staticUse, _applyMemberUse);
     switch (staticUse.kind) {
-      case StaticUseKind.STATIC_TEAR_OFF:
-        applyImpact(_backend.registerGetOfStaticFunction());
-        break;
-      case StaticUseKind.FIELD_GET:
-      case StaticUseKind.FIELD_SET:
-      case StaticUseKind.CLOSURE:
-        // TODO(johnniwinther): Avoid this. Currently [FIELD_GET] and
-        // [FIELD_SET] contains [BoxFieldElement]s which we cannot enqueue.
-        // Also [CLOSURE] contains [LocalFunctionElement] which we cannot
-        // enqueue.
-        addElement = false;
-        break;
-      case StaticUseKind.SUPER_FIELD_SET:
-      case StaticUseKind.SUPER_TEAR_OFF:
-      case StaticUseKind.GENERAL:
-      case StaticUseKind.DIRECT_USE:
-        break;
       case StaticUseKind.CONSTRUCTOR_INVOKE:
       case StaticUseKind.CONST_CONSTRUCTOR_INVOKE:
       case StaticUseKind.REDIRECTION:
         processTypeUse(new TypeUse.instantiation(staticUse.type));
         break;
-      case StaticUseKind.DIRECT_INVOKE:
-        _registerInstanceMethod(staticUse.element);
+      default:
         break;
     }
-    if (addElement) {
-      _addToWorkList(element);
-    }
   }
 
   void processTypeUse(TypeUse typeUse) {
@@ -415,11 +227,6 @@ class CodegenEnqueuer extends EnqueuerImpl {
     assert(!type.isTypeVariable || !type.element.enclosingElement.isTypedef);
   }
 
-  void _registerCallMethodWithFreeTypeVariables(Element element) {
-    applyImpact(_backend.registerCallMethodWithFreeTypeVariables(element,
-        forResolution: false));
-  }
-
   void _registerClosurizedMember(TypedElement element) {
     assert(element.isInstanceMember);
     if (element.type.containsTypeVariables) {
@@ -468,24 +275,12 @@ class CodegenEnqueuer extends EnqueuerImpl {
   bool isProcessed(Element member) =>
       member.isAbstract || generatedCode.containsKey(member);
 
-  void _registerNoSuchMethod(Element element) {
-    if (!_enabledNoSuchMethod && _backend.enabledNoSuchMethod) {
-      applyImpact(_backend.enableNoSuchMethod());
-      _enabledNoSuchMethod = true;
-    }
-  }
-
   void forgetEntity(Element element, Compiler compiler) {
     _universe.forgetElement(element, compiler);
-    _processedClasses.remove(element);
-    _instanceMembersByName[element.name]?.remove(element);
-    _instanceFunctionsByName[element.name]?.remove(element);
     generatedCode.remove(element);
     if (element is MemberElement) {
       for (Element closure in element.nestedClosures) {
         generatedCode.remove(closure);
-        removeFromSet(_instanceMembersByName, closure);
-        removeFromSet(_instanceFunctionsByName, closure);
       }
     }
   }
@@ -494,11 +289,5 @@ class CodegenEnqueuer extends EnqueuerImpl {
   Iterable<Entity> get processedEntities => generatedCode.keys;
 
   @override
-  Iterable<ClassEntity> get processedClasses => _processedClasses;
-}
-
-void removeFromSet(Map<String, Set<Element>> map, Element element) {
-  Set<Element> set = map[element.name];
-  if (set == null) return;
-  set.remove(element);
+  Iterable<ClassEntity> get processedClasses => _universe.processedClasses;
 }