Use Zone to correctly measure async operations.

pkg/compiler/lib/src/compiler.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.compiler_base;
 
 import 'dart:async' show EventSink, Future;
 
 import '../compiler_new.dart' as api;
 import 'cache_strategy.dart' show CacheStrategy;
 import 'closure.dart' as closureMapping show ClosureTask;
 import 'common/backend_api.dart' show Backend;
 import 'common/codegen.dart' show CodegenWorkItem;
 import 'common/names.dart' show Selectors;
 import 'common/names.dart' show Identifiers, Uris;
 import 'common/registry.dart' show EagerRegistry, Registry;
 import 'common/resolution.dart'
     show ParsingContext, Resolution, ResolutionWorkItem, ResolutionImpact;
-import 'common/tasks.dart' show CompilerTask, GenericTask;
+import 'common/tasks.dart' show CompilerTask, GenericTask, Measurer;
 import 'common/work.dart' show ItemCompilationContext, WorkItem;
 import 'common.dart';
 import 'compile_time_constants.dart';
 import 'constants/values.dart';
 import 'core_types.dart' show CoreClasses, CoreTypes;
 import 'dart_backend/dart_backend.dart' as dart_backend;
 import 'dart_types.dart' show DartType, DynamicType, InterfaceType, Types;
 import 'deferred_load.dart' show DeferredLoadTask;
 import 'diagnostics/code_location.dart';
 import 'diagnostics/diagnostic_listener.dart' show DiagnosticReporter;
@@ skipping 43 matching lines @@
 import 'typechecker.dart' show TypeCheckerTask;
 import 'types/types.dart' as ti;
 import 'universe/selector.dart' show Selector;
 import 'universe/universe.dart' show Universe;
 import 'universe/use.dart' show StaticUse;
 import 'universe/world_impact.dart' show ImpactStrategy, WorldImpact;
 import 'util/util.dart' show Link, Setlet;
 import 'world.dart' show World;
 
 abstract class Compiler implements LibraryLoaderListener {
-  final Stopwatch totalCompileTime = new Stopwatch();
+  /// Helper instance for measurements in [CompilerTask].
+  ///
+  /// Note: MUST be first field to ensure [Measurer.wallclock] is started
+  /// before other computations.
+  final Measurer measurer = new Measurer();
+
   final IdGenerator idGenerator = new IdGenerator();
   World world;
   Types types;
   _CompilerCoreTypes _coreTypes;
   _CompilerDiagnosticReporter _reporter;
   _CompilerResolution _resolution;
   ParsingContext _parsingContext;
 
   final CacheStrategy cacheStrategy;
 
@@ skipping 34 matching lines @@
 
   /// Output provider from user of Compiler API.
   api.CompilerOutput userOutputProvider;
 
   List<Uri> librariesToAnalyzeWhenRun;
 
   ResolvedUriTranslator get resolvedUriTranslator;
 
   Tracer tracer;
 
-  CompilerTask measuredTask;
   LibraryElement coreLibrary;
   LibraryElement asyncLibrary;
 
   LibraryElement mainApp;
   FunctionElement mainFunction;
 
   /// Initialized when dart:mirrors is loaded.
   LibraryElement mirrorsLibrary;
 
   /// Initialized when dart:typed_data is loaded.
@@ skipping 78 matching lines @@
   LibraryLoaderTask libraryLoader;
   SerializationTask serialization;
   ResolverTask resolver;
   closureMapping.ClosureTask closureToClassMapper;
   TypeCheckerTask checker;
   ti.TypesTask typesTask;
   Backend backend;
 
   GenericTask reuseLibraryTask;
 
+  GenericTask selfTask;
+
   /// The constant environment for the frontend interpretation of compile-time
   /// constants.
   ConstantEnvironment constants;
 
   EnqueueTask enqueuer;
   DeferredLoadTask deferredLoadTask;
   MirrorUsageAnalyzerTask mirrorUsageAnalyzerTask;
   DumpInfoTask dumpInfoTask;
 
   /// A customizable filter that is applied to enqueued work items.
@@ skipping 95 matching lines @@
       resolver = createResolverTask(),
       closureToClassMapper = new closureMapping.ClosureTask(this),
       checker = new TypeCheckerTask(this),
       typesTask = new ti.TypesTask(this),
       constants = backend.constantCompilerTask,
       deferredLoadTask = new DeferredLoadTask(this),
       mirrorUsageAnalyzerTask = new MirrorUsageAnalyzerTask(this),
       enqueuer = new EnqueueTask(this),
       dumpInfoTask = new DumpInfoTask(this),
       reuseLibraryTask = new GenericTask('Reuse library', this),
+      selfTask = new GenericTask('self', this),
     ];
 
     _parsingContext =
         new ParsingContext(reporter, options, parser, patchParser, backend);
 
     tasks.addAll(backend.tasks);
   }
 
   /// Creates the scanner task.
   ///
@@ skipping 19 matching lines @@
       options.disableTypeInference || compilationFailed;
 
   void unimplemented(Spannable spannable, String methodName) {
     reporter.internalError(spannable, "$methodName not implemented.");
   }
 
   // Compiles the dart script at [uri].
   //
   // The resulting future will complete with true if the compilation
   // succeeded.
-  Future<bool> run(Uri uri) {
-    totalCompileTime.start();
+  Future<bool> run(Uri uri) => selfTask.measureSubtask("Compiler.run", () {
+    measurer.startWallClock();

[Johnni Winther, 2016/04/25 09:23:02]

Why do call [startWallClock] here? Isn't is already started?

What about the time used in the subclass (apiimpl) before its super-call?

[ahe, 2016/04/26 11:35:00]

For normal dart2js runs from the command line, it is started already. However,
when calling run multiple times, it isn't.
This isn't ideal, but I'm not sure what would be a better alternative.

 
     return new Future.sync(() => runInternal(uri))
         .catchError((error) => _reporter.onError(uri, error))
         .whenComplete(() {
       tracer.close();
-      totalCompileTime.stop();
+      measurer.stopWallClock();
     }).then((_) {
       return !compilationFailed;
     });
-  }
+  });
 
   /// This method is called immediately after the [LibraryElement] [library] has
   /// been created.
   ///
   /// Use this callback method to store references to specific libraries.
   /// Note that [library] has not been scanned yet, nor has its imports/exports
   /// been resolved.
   void onLibraryCreated(LibraryElement library) {
     Uri uri = library.canonicalUri;
     if (uri == Uris.dart_core) {
@@ skipping 366 matching lines @@
         .then((LibraryElement library) {
       if (library == null) return null;
       fullyEnqueueLibrary(library, enqueuer.resolution);
       emptyQueue(enqueuer.resolution);
       enqueuer.resolution.logSummary(reporter.log);
       return library;
     });
   }
 
   /// Performs the compilation when all libraries have been loaded.
-  void compileLoadedLibraries() {
+  void compileLoadedLibraries()
+      => selfTask.measureSubtask("Compiler.compileLoadedLibraries", () {
+
     computeMain();
 
     mirrorUsageAnalyzerTask.analyzeUsage(mainApp);
 
     // In order to see if a library is deferred, we must compute the
     // compile-time constants that are metadata.  This means adding
     // something to the resolution queue.  So we cannot wait with
     // this until after the resolution queue is processed.
     deferredLoadTask.beforeResolution(this);
     impactStrategy = backend.createImpactStrategy(
@@ skipping 82 matching lines @@
     int programSize = backend.assembleProgram();
 
     if (options.dumpInfo) {
       dumpInfoTask.reportSize(programSize);
       dumpInfoTask.dumpInfo();
     }
 
     backend.sourceInformationStrategy.onComplete();
 
     checkQueues();
-  }
+  });
 
   void fullyEnqueueLibrary(LibraryElement library, Enqueuer world) {
     void enqueueAll(Element element) {
       fullyEnqueueTopLevelElement(element, world);
     }
     library.implementation.forEachLocalMember(enqueueAll);
   }
 
   void fullyEnqueueTopLevelElement(Element element, Enqueuer world) {
     if (element.isClass) {
@@ skipping 15 matching lines @@
         for (MetadataAnnotation metadata in library.metadata) {
           metadata.ensureResolved(resolution);
         }
       }
     }
   }
 
   /**
    * Empty the [world] queue.
    */
-  void emptyQueue(Enqueuer world) {
+  void emptyQueue(Enqueuer world)
+      => selfTask.measureSubtask("Compiler.emptyQueue", () {
     world.forEach((WorkItem work) {
-      reporter.withCurrentElement(work.element, () {
-        world.applyImpact(work.element, work.run(this, world));
-      });
+      reporter.withCurrentElement(
+          work.element, () => selfTask.measureSubtask("world.applyImpact", () {
+        world.applyImpact(
+            work.element,
+            selfTask.measureSubtask("work.run", () => work.run(this, world)));
+      }));
     });
-  }
+  });
 
-  void processQueue(Enqueuer world, Element main) {
+  void processQueue(Enqueuer world, Element main)
+      => selfTask.measureSubtask("Compiler.processQueue", () {
     world.nativeEnqueuer.processNativeClasses(libraryLoader.libraries);
     if (main != null && !main.isMalformed) {
       FunctionElement mainMethod = main;
       mainMethod.computeType(resolution);
       if (mainMethod.functionSignature.parameterCount != 0) {
         // The first argument could be a list of strings.
         backend.listImplementation.ensureResolved(resolution);
         backend.registerInstantiatedType(
             backend.listImplementation.rawType, world, globalDependencies);
         backend.stringImplementation.ensureResolved(resolution);
         backend.registerInstantiatedType(
             backend.stringImplementation.rawType, world, globalDependencies);
 
         backend.registerMainHasArguments(world);
       }
       world.addToWorkList(main);
     }
     if (options.verbose) {
       progress.reset();
     }
     emptyQueue(world);
     world.queueIsClosed = true;
     // Notify the impact strategy impacts are no longer needed for this
     // enqueuer.
     impactStrategy.onImpactUsed(world.impactUse);
     backend.onQueueClosed();
     assert(compilationFailed || world.checkNoEnqueuedInvokedInstanceMethods());
-  }
+  });
 
   /**
    * Perform various checks of the queues. This includes checking that
    * the queues are empty (nothing was added after we stopped
    * processing the queues). Also compute the number of methods that
    * were resolved, but not compiled (aka excess resolution).
    */
   checkQueues() {
     for (Enqueuer world in [enqueuer.resolution, enqueuer.codegen]) {
       world.forEach((WorkItem work) {
@@ skipping 20 matching lines @@
         resolved.remove(e);
       }
     }
     reporter.log('Excess resolution work: ${resolved.length}.');
     for (Element e in resolved) {
       reporter.reportWarningMessage(e, MessageKind.GENERIC,
           {'text': 'Warning: $e resolved but not compiled.'});
     }
   }
 
-  WorldImpact analyzeElement(Element element) {
+  WorldImpact analyzeElement(Element element)
+      => selfTask.measureSubtask("Compiler.analyzeElement", () {
     assert(invariant(
         element,
         element.impliesType ||
             element.isField ||
             element.isFunction ||
             element.isConstructor ||
             element.isGetter ||
             element.isSetter,
         message: 'Unexpected element kind: ${element.kind}'));
     assert(invariant(element, element is AnalyzableElement,
         message: 'Element $element is not analyzable.'));
     assert(invariant(element, element.isDeclaration));
     return resolution.computeWorldImpact(element);
-  }
+  });
 
-  WorldImpact analyze(ResolutionWorkItem work, ResolutionEnqueuer world) {
+  WorldImpact analyze(ResolutionWorkItem work,
+                      ResolutionEnqueuer world)
+      => selfTask.measureSubtask("Compiler.analyze", () {
     assert(invariant(work.element, identical(world, enqueuer.resolution)));
     assert(invariant(work.element, !work.isAnalyzed,
         message: 'Element ${work.element} has already been analyzed'));
     if (shouldPrintProgress) {
       // TODO(ahe): Add structured diagnostics to the compiler API and
       // use it to separate this from the --verbose option.
       if (phase == PHASE_RESOLVING) {
         reporter.log('Resolved ${enqueuer.resolution.processedElements.length} '
             'elements.');
         progress.reset();
       }
     }
     AstElement element = work.element;
     if (world.hasBeenProcessed(element)) {
       return const WorldImpact();
     }
     WorldImpact worldImpact = analyzeElement(element);
     backend.onElementResolved(element);
     world.registerProcessedElement(element);
     return worldImpact;
-  }
+  });
 
   WorldImpact codegen(CodegenWorkItem work, CodegenEnqueuer world) {
     assert(invariant(work.element, identical(world, enqueuer.codegen)));
     if (shouldPrintProgress) {
       // TODO(ahe): Add structured diagnostics to the compiler API and
       // use it to separate this from the --verbose option.
       reporter
           .log('Compiled ${enqueuer.codegen.generatedCode.length} methods.');
       progress.reset();
     }
@@ skipping 962 matching lines @@
   _ElementScanner(this.scanner);
   void scanLibrary(LibraryElement library) => scanner.scanLibrary(library);
   void scanUnit(CompilationUnitElement unit) => scanner.scan(unit);
 }
 
 class _EmptyEnvironment implements Environment {
   const _EmptyEnvironment();
 
   String valueOf(String key) => null;
 }