Remove direct access to enqueuer through use of WorldImpact

pkg/compiler/lib/src/enqueue.dart

 // 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.
 
 library dart2js.enqueue;
 
 import 'dart:collection' show Queue;
 
 import 'cache_strategy.dart';
 import 'common/backend_api.dart' show Backend;
@@ skipping 61 matching lines @@
     resolution.forgetElement(element, compiler);
     codegen.forgetElement(element, compiler);
   }
 }
 
 abstract class Enqueuer {
   CompilerTask get task;
   WorldBuilder get universe;
   native.NativeEnqueuer get nativeEnqueuer;
   void forgetElement(Element element, Compiler compiler);
+
+  // TODO(johnniwinther): Initialize [_impactStrategy] to `null`.
+  ImpactStrategy _impactStrategy = const ImpactStrategy();
+
+  ImpactStrategy get impactStrategy => _impactStrategy;
+
+  void open(ImpactStrategy impactStrategy) {
+    _impactStrategy = impactStrategy;
+  }
+
+  void close() {
+    // TODO(johnniwinther): Set [_impactStrategy] to `null` and [queueIsClosed]
+    // to `false` here.

[Harry Terkelsen, 2016/11/28 19:03:06]

you mean set [queueIsClosed] to true?

[Johnni Winther, 2016/11/29 08:01:37]

Yes :)

+    _impactStrategy = const ImpactStrategy();
+  }
+
   void processInstantiatedClassMembers(ClassElement cls);
   void processInstantiatedClassMember(ClassElement cls, Element member);
   void handleUnseenSelectorInternal(DynamicUse dynamicUse);
   void registerStaticUse(StaticUse staticUse);
   void registerStaticUseInternal(StaticUse staticUse);
   void registerDynamicUse(DynamicUse dynamicUse);
 
   /// Returns [:true:] if this enqueuer is the resolution enqueuer.
   bool get isResolutionQueue;
 
@@ skipping 11 matching lines @@
   void addToWorkList(Element element);
 
   void enableIsolateSupport();
 
   void registerInstantiatedType(InterfaceType type);
   void forEach(void f(WorkItem work));
 
   /// Apply the [worldImpact] to this enqueuer. If the [impactSource] is provided
   /// the impact strategy will remove it from the element impact cache, if it is
   /// no longer needed.
-  void applyImpact(ImpactStrategy impactStrategy, WorldImpact worldImpact,
-      {Element impactSource});
+  void applyImpact(WorldImpact worldImpact, {Element impactSource});
   bool checkNoEnqueuedInvokedInstanceMethods();
   void logSummary(log(message));
 
   /// Returns [:true:] if [member] has been processed by this enqueuer.
   bool isProcessed(Element member);
 
   Iterable<Entity> get processedEntities;
 
   Iterable<ClassElement> get processedClasses;
 }
@@ skipping 16 matching lines @@
   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 ResolutionWorldBuilderImpl _universe;
 
   bool queueIsClosed = false;
 
   WorldImpactVisitor impactVisitor;
 
-  ImpactStrategy impactStrategy;
-
   ResolutionEnqueuer(
       this.task,
       this.options,
       this.resolution,
       this.filter,
       this.strategy,
       this.globalDependencies,
       Backend backend,
       CommonElements commonElements,
       CacheStrategy cacheStrategy,
@@ skipping 24 matching lines @@
   /**
    * Documentation wanted -- johnniwinther
    *
    * Invariant: [element] must be a declaration element.
    */
   void addToWorkList(Element element) {
     assert(invariant(element, element.isDeclaration));
     internalAddToWorkList(element);
   }
 
-  void applyImpact(ImpactStrategy impactStrategy, WorldImpact worldImpact,
-      {Element impactSource}) {
+  void applyImpact(WorldImpact worldImpact, {Element impactSource}) {
+    if (worldImpact.isEmpty) return;
     impactStrategy.visitImpact(
         impactSource, worldImpact, impactVisitor, impactUse);
   }
 
   void registerInstantiatedType(InterfaceType type) {
     _registerInstantiatedType(type, globalDependency: true);
   }
 
   void _registerInstantiatedType(InterfaceType type,
       {ConstructorElement constructor,
       bool mirrorUsage: false,
       bool nativeUsage: false,
       bool globalDependency: false,
       bool isRedirection: false}) {
     task.measure(() {
       ClassElement cls = type.element;
       cls.ensureResolved(resolution);
       bool isNative = backend.isNative(cls);
       _universe.registerTypeInstantiation(type,
           constructor: constructor,
           isNative: isNative,
           byMirrors: mirrorUsage,
           isRedirection: isRedirection, onImplemented: (ClassElement cls) {
-        backend.registerImplementedClass(cls, this);
+        applyImpact(backend.registerImplementedClass(cls, forResolution: true));
       });
       if (globalDependency && !mirrorUsage) {
         globalDependencies.registerDependency(type.element);
       }
       if (nativeUsage) {
         nativeEnqueuer.onInstantiatedType(type);
       }
       backend.registerInstantiatedType(type);
       // TODO(johnniwinther): Share this reasoning with [Universe].
       if (!cls.isAbstract || isNative || mirrorUsage) {
@@ skipping 44 matching lines @@
         addToWorkList(member);
         return;
       }
     } else if (member.isFunction) {
       FunctionElement function = member;
       function.computeType(resolution);
       if (function.name == Identifiers.noSuchMethod_) {
         registerNoSuchMethod(function);
       }
       if (function.name == Identifiers.call && !cls.typeVariables.isEmpty) {
-        registerCallMethodWithFreeTypeVariables(function);
+        _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, openWorld)) {
         registerClosurizedMember(function);
         addToWorkList(function);
         return;
       }
       // Store the member in [instanceFunctionsByName] to catch
       // getters on the function.
@@ skipping 44 matching lines @@
         if (_processedClasses.contains(superclass)) return;
 
         _processedClasses.add(superclass);
         recentClasses.add(superclass);
         superclass.ensureResolved(resolution);
         superclass.implementation.forEachMember(processInstantiatedClassMember);
         resolution.ensureClassMembers(superclass);
         // We only tell the backend once that [superclass] was instantiated, so
         // any additional dependencies must be treated as global
         // dependencies.
-        backend.registerInstantiatedClass(superclass, this);
+        applyImpact(
+            backend.registerInstantiatedClass(superclass, forResolution: true));
       }
 
       ClassElement superclass = cls;
       while (superclass != null) {
         processClass(superclass);
         superclass = superclass.superclass;
       }
     });
   }
 
@@ skipping 63 matching lines @@
    */
   void registerStaticUse(StaticUse staticUse) {
     strategy.processStaticUse(this, staticUse);
   }
 
   void registerStaticUseInternal(StaticUse staticUse) {
     Element element = staticUse.element;
     assert(invariant(element, element.isDeclaration,
         message: "Element ${element} is not the declaration."));
     _universe.registerStaticUse(staticUse);
-    backend.registerStaticUse(this, element);
+    applyImpact(backend.registerStaticUse(element, forResolution: true));
     bool addElement = true;
     switch (staticUse.kind) {
       case StaticUseKind.STATIC_TEAR_OFF:
-        backend.registerGetOfStaticFunction(this);
+        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.
         LocalFunctionElement closure = staticUse.element;
         if (closure.type.containsTypeVariables) {
@@ skipping 56 matching lines @@
   }
 
   void _registerIsCheck(DartType type) {
     type = _universe.registerIsCheck(type, resolution);
     // Even in checked mode, type annotations for return type and argument
     // types do not imply type checks, so there should never be a check
     // against the type variable of a typedef.
     assert(!type.isTypeVariable || !type.element.enclosingElement.isTypedef);
   }
 
-  void registerCallMethodWithFreeTypeVariables(Element element) {
-    backend.registerCallMethodWithFreeTypeVariables(element, this);
+  void _registerCallMethodWithFreeTypeVariables(Element element) {
+    applyImpact(backend.registerCallMethodWithFreeTypeVariables(element,
+        forResolution: true));
     _universe.callMethodsWithFreeTypeVariables.add(element);
   }
 
   void registerClosurizedMember(TypedElement element) {
     assert(element.isInstanceMember);
     if (element.computeType(resolution).containsTypeVariables) {
-      backend.registerClosureWithFreeTypeVariables(element, this);
+      applyImpact(backend.registerClosureWithFreeTypeVariables(element,
+          forResolution: true));
       _universe.closuresWithFreeTypeVariables.add(element);
     }
-    backend.registerBoundClosure(this);
+    applyImpact(backend.registerBoundClosure());
     _universe.closurizedMembers.add(element);
   }
 
   void forEach(void f(WorkItem work)) {
     do {
       while (queue.isNotEmpty) {
         // TODO(johnniwinther): Find an optimal process order.
         filter.processWorkItem(f, queue.removeLast());
       }
       List recents = recentClasses.toList(growable: false);
@@ skipping 79 matching lines @@
       }
     }
 
     if (element.isGetter && element.name == Identifiers.runtimeType_) {
       // Enable runtime type support if we discover a getter called runtimeType.
       // We have to enable runtime type before hitting the codegen, so
       // that constructors know whether they need to generate code for
       // runtime type.
       _universe.hasRuntimeTypeSupport = true;
       // TODO(ahe): Record precise dependency here.
-      backend.registerRuntimeType(this);
+      applyImpact(backend.registerRuntimeType());
     } else if (commonElements.isFunctionApplyMethod(element)) {
       _universe.hasFunctionApplySupport = true;
     }
 
     return true;
   }
 
   void registerNoSuchMethod(Element element) {
     backend.registerNoSuchMethod(element);
   }
 
   void enableIsolateSupport() {
     _universe.hasIsolateSupport = true;
-    backend.enableIsolateSupport(this);
+    applyImpact(backend.enableIsolateSupport(forResolution: true));
   }
 
   /**
    * Adds an action to the deferred task queue.
    *
    * The action is performed the next time the resolution queue has been
    * emptied.
    *
    * The queue is processed in FIFO order.
    */
@@ skipping 121 matching lines @@
 }
 
 typedef void _DeferredActionFunction();
 
 class _DeferredAction {
   final Element element;
   final _DeferredActionFunction action;
 
   _DeferredAction(this.element, this.action);
 }