Be smarter about when disabling tree-shaking.

dart/sdk/lib/_internal/compiler/implementation/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.
 
 part of dart2js;
 
 class EnqueueTask extends CompilerTask {
   final ResolutionEnqueuer resolution;
   final CodegenEnqueuer codegen;
 
@@ skipping 44 matching lines @@
       allElementsByName[name] = allElementsByName.putIfAbsent(
           name, () => const Link<Element>()).prepend(element);
       for (var link = members; !link.isEmpty; link = link.tail) {
         addMemberByName(link.head);
       }
     }
 
     compiler.libraries.values.forEach(addMemberByName);
   }
 
-
   String get name => 'Enqueue';
 
   EnqueueTask(Compiler compiler)
     : resolution = new ResolutionEnqueuer(
           compiler, compiler.backend.createItemCompilationContext),
       codegen = new CodegenEnqueuer(
           compiler, compiler.backend.createItemCompilationContext),
       super(compiler) {
     codegen.task = this;
     resolution.task = this;
@@ skipping 12 matching lines @@
       = new Map<String, Link<Element>>();
   final Map<String, Link<Element>> instanceFunctionsByName
       = new Map<String, Link<Element>>();
   final Set<ClassElement> seenClasses = new Set<ClassElement>();
   final Universe universe = new Universe();
 
   bool queueIsClosed = false;
   EnqueueTask task;
   native.NativeEnqueuer nativeEnqueuer;  // Set by EnqueueTask
 
+  bool hasEnqueuedEverything = false;
+
   Enqueuer(this.name, this.compiler,
            ItemCompilationContext itemCompilationContextCreator())
     : this.itemCompilationContextCreator = itemCompilationContextCreator;
 
   /// Returns [:true:] if this enqueuer is the resolution enqueuer.
   bool get isResolutionQueue => false;
 
   /// Returns [:true:] if [member] has been processed by this enqueuer.
   bool isProcessed(Element member);
 
@@ skipping 227 matching lines @@
     // If dart:mirrors is loaded, a const symbol may be used to call a
     // static/top-level method or accessor, instantiate a class, call
     // an instance method or accessor with the given name.
     if (!compiler.mirrorsEnabled) return;
 
     task.ensureAllElementsByName();
 
     for (var link = task.allElementsByName[name];
          link != null && !link.isEmpty;
          link = link.tail) {
-      Element element = link.head;
-      if (Elements.isUnresolved(element)) {
-        // Ignore.
-      } else if (element.isConstructor()) {
-        ClassElement cls = element.declaration.getEnclosingClass();
-        registerInstantiatedType(cls.rawType, elements);
-        registerStaticUse(element.declaration);
-      } else if (element.impliesType()) {
-        // Don't enqueue classes, typedefs, and type variables.
-      } else if (Elements.isStaticOrTopLevel(element)) {
-        registerStaticUse(element.declaration);
-      } else if (element.isInstanceMember()) {
-        if (element.isFunction()) {
-          int arity =
-              element.asFunctionElement().requiredParameterCount(compiler);
-          Selector selector =
-              new Selector.call(element.name, element.getLibrary(), arity);
-          registerInvocation(element.name, selector);
-        } else if (element.isSetter()) {
-          Selector selector =
-              new Selector.setter(element.name, element.getLibrary());
-          registerInvokedSetter(element.name, selector);
-        } else if (element.isGetter()) {
-          Selector selector =
-              new Selector.getter(element.name, element.getLibrary());
-          registerInvokedGetter(element.name, selector);
-        } else if (element.isField()) {
-          Selector selector =
-              new Selector.setter(element.name, element.getLibrary());
-          registerInvokedSetter(element.name, selector);
-          selector =
-              new Selector.getter(element.name, element.getLibrary());
-          registerInvokedGetter(element.name, selector);
-        }
+      pretendElementWasUsed(link.head, elements);
+    }
+  }
+
+  void pretendElementWasUsed(Element element, TreeElements elements) {
+    if (Elements.isUnresolved(element)) {
+      // Ignore.
+    } else if (element.isConstructor()) {
+      ClassElement cls = element.declaration.getEnclosingClass();
+      registerInstantiatedType(cls.rawType, elements);
+      registerStaticUse(element.declaration);
+    } else if (element.impliesType()) {
+      // Don't enqueue classes, typedefs, and type variables.
+    } else if (Elements.isStaticOrTopLevel(element)) {
+      registerStaticUse(element.declaration);
+    } else if (element.isInstanceMember()) {
+      if (element.isFunction()) {
+        int arity =
+            element.asFunctionElement().requiredParameterCount(compiler);
+        Selector selector =
+            new Selector.call(element.name, element.getLibrary(), arity);
+        registerInvocation(element.name, selector);
+      } else if (element.isSetter()) {
+        Selector selector =
+            new Selector.setter(element.name, element.getLibrary());
+        registerInvokedSetter(element.name, selector);
+      } else if (element.isGetter()) {
+        Selector selector =
+            new Selector.getter(element.name, element.getLibrary());
+        registerInvokedGetter(element.name, selector);
+      } else if (element.isField()) {
+        Selector selector =
+            new Selector.setter(element.name, element.getLibrary());
+        registerInvokedSetter(element.name, selector);
+        selector = new Selector.getter(element.name, element.getLibrary());
+        registerInvokedGetter(element.name, selector);
       }
     }
   }
 
   /// Called when [:new Symbol(...):] is seen.
   void registerNewSymbol(TreeElements elements) {
   }
 
+  void enqueueEverything() {
+    if (hasEnqueuedEverything) return;
+    compiler.log('Enqueuing everything');
+    task.ensureAllElementsByName();
+    for (Link link in task.allElementsByName.values) {
+      for (Element element in link) {
+        pretendElementWasUsed(element, compiler.globalDependencies);
+      }
+    }
+    hasEnqueuedEverything = true;
+  }
+
   processLink(Map<String, Link<Element>> map,
               SourceString n,
               bool f(Element e)) {
     String memberName = n.slowToString();
     Link<Element> members = map[memberName];
     if (members != null) {
       LinkBuilder<Element> remaining = new LinkBuilder<Element>();
       for (; !members.isEmpty; members = members.tail) {
         if (!f(members.head)) remaining.addLast(members.head);
       }
@@ skipping 52 matching lines @@
 
   /**
    * Documentation wanted -- johnniwinther
    *
    * Invariant: [element] must be a declaration element.
    */
   void registerStaticUse(Element element) {
     if (element == null) return;
     assert(invariant(element, element.isDeclaration));
     addToWorkList(element);
+    compiler.backend.registerStaticUse(element, this);
   }
 
   void registerGetOfStaticFunction(FunctionElement element) {
     registerStaticUse(element);
     registerInstantiatedClass(compiler.closureClass,
                               compiler.globalDependencies);
     universe.staticFunctionsNeedingGetter.add(element);
   }
 
   void registerDynamicInvocation(SourceString methodName, Selector selector) {
@@ skipping 271 matching lines @@
     while(!queue.isEmpty) {
       // TODO(johnniwinther): Find an optimal process order for codegen.
       f(queue.removeLast());
     }
   }
 
   void _logSpecificSummary(log(message)) {
     log('Compiled ${generatedCode.length} methods.');
   }
 }