[dart2js] Moving runtime allocations to pkg:dart2js_runtime_metrics

* Stores runtime information on `$runtimeMetrics` instead of `$__dart_deferred_initializers__`
* Keys each app's runtime allocations onto self.runtimeMetrics.$currentScript

Change-Id: I6612fd2a5ac792bfcb7580ffe91d5391b80d5965
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/242507
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Reviewed-by: Stephen Adams <sra@google.com>
Commit-Queue: Mark Zhou <markzipan@google.com>

pkg/compiler/lib/src/js_emitter/main_call_stub_generator.dart

@@ -6,6 +6,7 @@
 
 library dart2js.js_emitter.main_call_stub_generator;
 
+import 'package:compiler/src/options.dart';
 import 'package:js_runtime/shared/embedded_names.dart' as embeddedNames;
 
 import '../common/elements.dart';
@@ -16,8 +17,12 @@ import '../js/js.dart' show js;
 import 'code_emitter_task.dart' show Emitter;
 
 class MainCallStubGenerator {
-  static jsAst.Statement generateInvokeMain(CommonElements commonElements,
-      Emitter emitter, FunctionEntity main, bool requiresStartupMetrics) {
+  static jsAst.Statement generateInvokeMain(
+      CommonElements commonElements,
+      Emitter emitter,
+      FunctionEntity main,
+      bool requiresStartupMetrics,
+      CompilerOptions options) {
     jsAst.Expression mainAccess = emitter.staticFunctionAccess(main);
     jsAst.Expression currentScriptAccess =
         emitter.generateEmbeddedGlobalAccess(embeddedNames.CURRENT_SCRIPT);
@@ -96,6 +101,10 @@ class MainCallStubGenerator {
         if (#startupMetrics) {
           init.#startupMetricsEmbeddedGlobal.add('callMainMs');
         }
+        if (#isCollectingRuntimeMetrics) {
+          self.#runtimeMetricsContainer = self.#runtimeMetricsContainer || Object.create(null);
+          self.#runtimeMetricsContainer[currentScript.src] = init.#runtimeMetricsEmbeddedGlobal;
+        }
         var callMain = #mainCallClosure;
         if (typeof dartMainRunner === "function") {
           dartMainRunner(callMain, []);
@@ -105,6 +114,9 @@ class MainCallStubGenerator {
       })''', {
       'currentScript': currentScriptAccess,
       'mainCallClosure': mainCallClosure,
+      'isCollectingRuntimeMetrics': options.experimentalTrackAllocations,
+      'runtimeMetricsContainer': embeddedNames.RUNTIME_METRICS_CONTAINER,
+      'runtimeMetricsEmbeddedGlobal': embeddedNames.RUNTIME_METRICS,
       'startupMetrics': requiresStartupMetrics,
       'startupMetricsEmbeddedGlobal': embeddedNames.STARTUP_METRICS,
     });

pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart

@@ -296,8 +296,12 @@ class ProgramBuilder {
   }
 
   js.Statement _buildInvokeMain() {
-    return MainCallStubGenerator.generateInvokeMain(_commonElements,
-        _task.emitter, _mainFunction, _backendUsage.requiresStartupMetrics);
+    return MainCallStubGenerator.generateInvokeMain(
+        _commonElements,
+        _task.emitter,
+        _mainFunction,
+        _backendUsage.requiresStartupMetrics,
+        _options);
   }
 
   DeferredFragment _buildDeferredFragment(LibrariesMap librariesMap) {

pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart

@@ -46,6 +46,11 @@ if (#startupMetrics) {
       .add("dartProgramMs");
 }
 
+if (#isCollectingRuntimeMetrics) {
+  dartProgram.$RUNTIME_METRICS = Object.create(null);
+  var allocations = dartProgram.$RUNTIME_METRICS['allocations'] = Object.create(null);
+}
+
 // Copies the own properties from [from] to [to].
 function copyProperties(from, to) {
   var keys = Object.keys(from);
@@ -420,10 +425,6 @@ function initializeDeferredHunk(hunk) {
   hunk(hunkHelpers, #embeddedGlobalsObject, holders, #staticState);
 }
 
-if (#isTrackingAllocations) {
-  var allocations = #deferredGlobal['allocations'] = {};
-}
-
 // Creates the holders.
 #holders;
 
@@ -523,7 +524,9 @@ const String _directAccessTestExpression = r'''
 /// This template is used for Dart 2.
 const String _deferredBoilerplate = '''
 function(hunkHelpers, #embeddedGlobalsObject, holdersList, #staticState) {
-
+if (#isCollectingRuntimeMetrics) {
+  var allocations = #embeddedGlobalsObject.#runtimeMetrics['allocations'];
+}
 // Builds the holders. They only contain the data for new holders.
 // If names are not set on functions, we do it now. Finally, updates the
 // holders of the main-fragment. Uses the provided holdersList to access the
@@ -751,8 +754,7 @@ class FragmentEmitter {
       //'stubName': js.string(_namer.stubNameField),
       //'argumentCount': js.string(_namer.fixedNames.requiredParameterField),
       //'defaultArgumentValues': js.string(_namer.fixedNames.defaultValuesField),
-      'deferredGlobal': ModelEmitter.deferredInitializersGlobal,
-      'isTrackingAllocations': _options.experimentalTrackAllocations,
+      'isCollectingRuntimeMetrics': _options.experimentalTrackAllocations,
       'prototypes': emitPrototypes(fragment),
       'inheritance': emitInheritance(fragment),
       'aliases': emitInstanceMethodAliases(fragment),
@@ -808,7 +810,9 @@ class FragmentEmitter {
     js.Expression code = js.js(_deferredBoilerplate, {
       // TODO(floitsch): don't just reference 'init'.
       'embeddedGlobalsObject': js.Parameter('init'),
+      'isCollectingRuntimeMetrics': _options.experimentalTrackAllocations,
       'staticState': DeferredHolderParameter(),
+      'runtimeMetrics': RUNTIME_METRICS,
       'updateHolders': updateHolders,
       'prototypes': fragment.classPrototypes,
       'closures': fragment.closurePrototypes,
@@ -1875,6 +1879,12 @@ class FragmentEmitter {
           js.string(STARTUP_METRICS), js.js('dartProgram.$STARTUP_METRICS')));
     }
 
+    if (_options.experimentalTrackAllocations) {
+      // Copy the metrics object that was stored on the main unit IIFE.
+      globals.add(js.Property(
+          js.string(RUNTIME_METRICS), js.js('dartProgram.$RUNTIME_METRICS')));
+    }
+
     js.ObjectInitializer globalsObject =
         js.ObjectInitializer(globals, isOneLiner: false);
 

pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart

@@ -27,6 +27,7 @@ import 'package:js_runtime/shared/embedded_names.dart'
         NATIVE_SUPERCLASS_TAG_NAME,
         RTI_UNIVERSE,
         RtiUniverseFieldNames,
+        RUNTIME_METRICS,
         STARTUP_METRICS,
         TearOffParametersPropertyNames,
         TYPE_TO_INTERCEPTOR_MAP,
@@ -368,19 +369,11 @@ class ModelEmitter {
     return js.Comment(generatedBy(_options, flavor: '$flavor'));
   }
 
-  List<js.Statement> buildDeferredInitializerGlobal() {
-    return [
-      js.js.statement(
-          'self.#deferredInitializers = '
-          'self.#deferredInitializers || Object.create(null);',
-          {'deferredInitializers': deferredInitializersGlobal}),
-      if (_options.experimentalTrackAllocations)
-        js.js.statement(
-            'self.#deferredInitializers["allocations"] = '
-            'self.#deferredInitializers["allocations"] '
-            '|| Object.create(null)',
-            {'deferredInitializers': deferredInitializersGlobal})
-    ];
+  js.Statement buildDeferredInitializerGlobal() {
+    return js.js.statement(
+        'self.#deferredInitializers = '
+        'self.#deferredInitializers || Object.create(null);',
+        {'deferredInitializers': deferredInitializersGlobal});
   }
 
   js.Statement buildStartupMetrics() {
@@ -431,7 +424,7 @@ var ${startupMetricsGlobal} =
     js.Program program = js.Program([
       buildGeneratedBy(),
       js.Comment(HOOKS_API_USAGE),
-      if (isSplit) ...buildDeferredInitializerGlobal(),
+      if (isSplit) buildDeferredInitializerGlobal(),
       if (_closedWorld.backendUsage.requiresStartupMetrics)
         buildStartupMetrics(),
       code
@@ -566,10 +559,7 @@ var ${startupMetricsGlobal} =
 
     js.Program program = js.Program([
       if (isFirst) buildGeneratedBy(),
-      if (isFirst) ...buildDeferredInitializerGlobal(),
-      if (_options.experimentalTrackAllocations)
-        js.js.statement("var allocations = #deferredGlobal['allocations']",
-            {'deferredGlobal': deferredInitializersGlobal}),
+      if (isFirst) buildDeferredInitializerGlobal(),
       js.js.statement('$deferredInitializersGlobal.current = #', code)
     ]);
 

pkg/dart2js_runtime_metrics/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.2.0
+
+- Adding `runtimeMetrics`.
+
 ## 0.1.0
 
 - Initial version.

pkg/dart2js_runtime_metrics/lib/_runtime_metrics_dart2js.dart

@@ -0,0 +1,5 @@
+// Copyright (c) 2022, 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.
+
+export 'dart:_dart2js_runtime_metrics' show runtimeMetrics;

pkg/dart2js_runtime_metrics/lib/_runtime_metrics_dartdevc.dart

@@ -0,0 +1,12 @@
+// Copyright (c) 2022, 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.
+
+/// A collection of metrics collected during the runtime of a Dart app.
+///
+/// The contents of the map depend on the platform. The map values are simple
+/// objects (strings, numbers, Booleans). There is always an entry for the key
+/// `'runtime'` with a [String] value.
+Map<String, Object> get runtimeMetrics {
+  return {'runtime': 'dartdevc'};
+}

pkg/dart2js_runtime_metrics/lib/_runtime_metrics_unknown.dart

@@ -0,0 +1,12 @@
+// Copyright (c) 2022, 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.
+
+/// A collection of metrics collected during the runtime of a Dart app.
+///
+/// The contents of the map depend on the platform. The map values are simple
+/// objects (strings, numbers, Booleans). There is always an entry for the key
+/// `'runtime'` with a [String] value.
+Map<String, Object> get runtimeMetrics {
+  return {'runtime': 'unknown'};
+}

pkg/dart2js_runtime_metrics/lib/_runtime_metrics_vm.dart

@@ -0,0 +1,12 @@
+// Copyright (c) 2022, 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.
+
+/// A collection of metrics collected during the runtime of a Dart app.
+///
+/// The contents of the map depend on the platform. The map values are simple
+/// objects (strings, numbers, Booleans). There is always an entry for the key
+/// `'runtime'` with a [String] value.
+Map<String, Object> get runtimeMetrics {
+  return {'runtime': 'vm'};
+}

pkg/dart2js_runtime_metrics/lib/runtime_metrics.dart

@@ -0,0 +1,8 @@
+// Copyright (c) 2022, 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.
+
+export '_runtime_metrics_unknown.dart'
+    if (dart.library._dart2js_runtime_metrics) '_runtime_metrics_dart2js.dart'
+    if (dart.library.ffi) '_runtime_metrics_vm.dart'
+    if (dart.library.js) '_runtime_metrics_dartdevc.dart';

pkg/dart2js_runtime_metrics/pubspec.yaml

@@ -1,7 +1,7 @@
 name: dart2js_runtime_metrics
 # This package is not intended for consumption on pub.dev. DO NOT publish.
 publish_to: none
-version: 0.1.0
+version: 0.2.0
 description: >-
   `dart2js` can generate extra code to measure certain activities.
   This library provides access to the measurements at runtime.

pkg/dart2js_runtime_metrics/test/runtime_metrics_test.dart

@@ -0,0 +1,51 @@
+// Copyright (c) 2022, 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.
+
+// dart2jsOptions=--experimental-track-allocations
+
+import 'package:dart2js_runtime_metrics/runtime_metrics.dart';
+import 'package:expect/expect.dart';
+
+void main() {
+  Map<String, Object> metrics = runtimeMetrics;
+
+  print('metrics: $metrics');
+
+  String expectedRuntime;
+  if (1.0 is! int) {
+    expectedRuntime = 'vm';
+  } else if (ClassWithLongName().toString().contains('minified:')) {
+    // dart2js minified: "Instance of 'minified:xy'".
+    expectedRuntime = 'dart2js';
+  } else if ('$main' == "Closure 'main'") {
+    // dart2js non-minified.
+    expectedRuntime = 'dart2js';
+  } else if ('$main'.startsWith('Closure: () => void from: function main()')) {
+    expectedRuntime = 'dartdevc';
+  } else {
+    throw 'Cannot feature-test current runtime:'
+        '\nmetrics = $metrics\n main = $main';
+  }
+
+  Expect.isTrue(metrics.containsKey('runtime'), "Has 'runtime' key: $metrics");
+  Expect.equals(expectedRuntime, metrics['runtime'],
+      "Expected 'runtime: $expectedRuntime': $metrics");
+
+  if (expectedRuntime == 'dart2js') {
+    Expect.isTrue(metrics.containsKey('allocations'));
+    return;
+  }
+
+  if (expectedRuntime == 'dartdevc') {
+    return;
+  }
+
+  if (expectedRuntime == 'vm') {
+    return;
+  }
+
+  throw 'Should not get here.';
+}
+
+class ClassWithLongName {}

pkg/js_runtime/lib/shared/embedded_names.dart

@@ -179,6 +179,12 @@ const DEFERRED_INITIALIZED = 'deferredInitialized';
 /// This embedded global is used for --experiment-new-rti.
 const RTI_UNIVERSE = 'typeUniverse';
 
+/// An embedded global used to collect and access runtime metrics.
+const RUNTIME_METRICS = 'rm';
+
+/// Global name that holds runtime metrics Dart2JS apps.
+const RUNTIME_METRICS_CONTAINER = 'runtimeMetrics';
+
 /// An embedded global used to collect and access startup metrics.
 const STARTUP_METRICS = 'sm';
 

sdk/lib/_internal/js_runtime/lib/dart2js_runtime_metrics.dart

@@ -4,7 +4,12 @@
 
 library dart2js_runtime_metrics;
 
-import 'dart:_js_helper' show fillLiteralMap, rawStartupMetrics;
+import 'dart:_js_helper'
+    show
+        copyAndStringifyProperties,
+        fillLiteralMap,
+        rawRuntimeMetrics,
+        rawStartupMetrics;
 
 /// A collection of metrics for events that happen before `main()` is entered.
 ///
@@ -35,3 +40,23 @@ Map<String, Object> get startupMetrics {
   fillLiteralMap(raw, result);
   return result;
 }
+
+/// A collection of metrics collected during the runtime of a Dart app.
+///
+/// The contents of the map depend on the platform. The map values are simple
+/// objects (strings, numbers, Booleans). There is always an entry for the key
+/// `'runtime'` with a [String] value.
+///
+/// This implementation for dart2js has the content (subject to change):
+///
+/// - `runtime`: `'dart2js'`
+///
+/// - `allocations`: A string representation of a Json Map<String, Object>,
+///   which holds every class or closure created at runtime. The key contains
+///   a resolved path of the class or closure. The value is currently unused.
+Map<String, Object> get runtimeMetrics {
+  final Map<String, Object> result = {'runtime': 'dart2js'};
+  final raw = rawRuntimeMetrics();
+  copyAndStringifyProperties(raw, result);
+  return result;
+}

sdk/lib/_internal/js_runtime/lib/js_helper.dart

@@ -21,6 +21,7 @@ import 'dart:_js_embedded_names'
         JsGetName,
         LEAF_TAGS,
         NATIVE_SUPERCLASS_TAG_NAME,
+        RUNTIME_METRICS,
         STARTUP_METRICS,
         STATIC_FUNCTION_NAME_PROPERTY_NAME,
         TearOffParametersPropertyNames;
@@ -1801,6 +1802,21 @@ fillLiteralSet(values, Set result) {
   return result;
 }
 
+/// Called by generated code to move and stringify properties from an object
+/// to a map literal.
+copyAndStringifyProperties(from, Map to) {
+  if (JS('bool', '!#', from)) return to;
+  List keys = JS('JSArray', r'Object.keys(#)', from);
+  int index = 0;
+  int length = getLength(keys);
+  while (index < length) {
+    var key = getIndex(keys, index++);
+    var value = JS('String', r'JSON.stringify(#[#])', from, key);
+    to[key] = value;
+  }
+  return to;
+}
+
 /// Returns the property [index] of the JavaScript array [array].
 getIndex(var array, int index) {
   return JS('var', r'#[#]', array, index);
@@ -3064,6 +3080,10 @@ Object? rawStartupMetrics() {
   return JS('JSArray', '#.a', JS_EMBEDDED_GLOBAL('', STARTUP_METRICS));
 }
 
+Object? rawRuntimeMetrics() {
+  return JS('', '#', JS_EMBEDDED_GLOBAL('', RUNTIME_METRICS));
+}
+
 /// Wraps the given [callback] within the current Zone.
 void Function(T)? wrapZoneUnaryCallback<T>(void Function(T)? callback) {
   // For performance reasons avoid wrapping if we are in the root zone.

sdk/lib/_internal/js_runtime/lib/shared/embedded_names.dart

@@ -179,6 +179,12 @@ const DEFERRED_INITIALIZED = 'deferredInitialized';
 /// This embedded global is used for --experiment-new-rti.
 const RTI_UNIVERSE = 'typeUniverse';
 
+/// An embedded global used to collect and access runtime metrics.
+const RUNTIME_METRICS = 'rm';
+
+/// Global name that holds runtime metrics Dart2JS apps.
+const RUNTIME_METRICS_CONTAINER = 'runtimeMetrics';
+
 /// An embedded global used to collect and access startup metrics.
 const STARTUP_METRICS = 'sm';