Performance improvements for the CPU profiler (#3274)

* Performance improvements for the CPU profiler

* review comments

packages/devtools_app/lib/src/profiler/cpu_profile_controller.dart

@@ -63,21 +63,17 @@ class CpuProfilerController
   List<ToggleFilter<CpuStackFrame>> get toggleFilters => _toggleFilters ??= [
         ToggleFilter<CpuStackFrame>(
           name: 'Hide Native code',
-          includeCallback: (stackFrame) => stackFrame.processedUrl.isNotEmpty,
+          includeCallback: (stackFrame) => !stackFrame.isNative,
           enabledByDefault: true,
         ),
         ToggleFilter<CpuStackFrame>(
           name: 'Hide core Dart libraries',
-          includeCallback: (stackFrame) =>
-              !stackFrame.processedUrl.startsWith('dart:'),
+          includeCallback: (stackFrame) => !stackFrame.isDartCore,
         ),
         if (serviceManager.connectedApp?.isFlutterAppNow ?? true)
           ToggleFilter<CpuStackFrame>(
             name: 'Hide core Flutter libraries',
-            includeCallback: (stackFrame) =>
-                !(stackFrame.processedUrl.startsWith('package:flutter/') ||
-                    stackFrame.name.startsWith('flutter::') ||
-                    stackFrame.processedUrl.startsWith('dart:ui')),
+            includeCallback: (stackFrame) => !stackFrame.isFlutterCore,
           ),
       ];
 

packages/devtools_app/lib/src/profiler/cpu_profile_model.dart

@@ -21,12 +21,13 @@ class CpuProfileData {
     @required this.cpuSamples,
     @required this.profileMetaData,
   }) {
-    _cpuProfileRoot = CpuStackFrame(
+    _cpuProfileRoot = CpuStackFrame._(
       id: rootId,
       name: rootName,
       verboseName: rootName,
       category: 'Dart',
       rawUrl: '',
+      processedUrl: '',
       profileMetaData: profileMetaData,
       parentId: null,
     );
@@ -407,16 +408,50 @@ class CpuStackFrame extends TreeNode<CpuStackFrame>
         DataSearchStateMixin,
         TreeDataSearchStateMixin<CpuStackFrame>,
         FlameChartDataMixin {
-  CpuStackFrame({
+  factory CpuStackFrame({
+    @required String id,
+    @required String name,
+    @required String verboseName,
+    @required String category,
+    @required String rawUrl,
+    @required String parentId,
+    @required CpuProfileMetaData profileMetaData,
+  }) {
+    assert(rawUrl != null);
+    return CpuStackFrame._(
+      id: id,
+      name: name,
+      verboseName: verboseName,
+      category: category,
+      rawUrl: rawUrl,
+      processedUrl: getSimplePackageUrl(rawUrl),
+      parentId: parentId,
+      profileMetaData: profileMetaData,
+    );
+  }
+
+  CpuStackFrame._({
     @required this.id,
     @required this.name,
     @required this.verboseName,
     @required this.category,
     @required this.rawUrl,
+    @required this.processedUrl,
     @required this.parentId,
     @required this.profileMetaData,
-  })  : processedUrl = getSimplePackageUrl(rawUrl),
-        assert(rawUrl != null);
+  });
+
+  /// Prefix for packages from the core Dart libraries.
+  static const dartPackagePrefix = 'dart:';
+
+  /// Prefix for packages from the core Flutter libraries.
+  static const flutterPackagePrefix = 'package:flutter/';
+
+  /// The Flutter namespace in C++ that is part of the Flutter Engine code.
+  static const flutterEnginePrefix = 'flutter::';
+
+  /// dart:ui is the library for the Dart part of the Flutter Engine code.
+  static const dartUiPrefix = 'dart:ui';
 
   final String id;
 
@@ -434,6 +469,23 @@ class CpuStackFrame extends TreeNode<CpuStackFrame>
 
   final CpuProfileMetaData profileMetaData;
 
+  bool get isNative =>
+      _isNative ??= id != CpuProfileData.rootId && processedUrl.isEmpty;
+
+  bool _isNative;
+
+  bool get isDartCore =>
+      _isDartCore ??= processedUrl.startsWith(dartPackagePrefix);
+
+  bool _isDartCore;
+
+  bool get isFlutterCore =>
+      _isFlutterCore ??= processedUrl.startsWith(flutterPackagePrefix) ||
+          name.startsWith(flutterEnginePrefix) ||
+          processedUrl.startsWith(dartUiPrefix);
+
+  bool _isFlutterCore;
+
   Iterable<String> get userTags => _userTagSampleCount.keys;
 
   /// Maps a user tag to the number of CPU samples associated with it.
@@ -517,12 +569,13 @@ class CpuStackFrame extends TreeNode<CpuStackFrame>
     bool copySampleCountsAndTags = true,
     bool resetInclusiveSampleCount = true,
   }) {
-    final copy = CpuStackFrame(
+    final copy = CpuStackFrame._(
       id: id ?? this.id,
       name: name ?? this.name,
       verboseName: verboseName ?? this.verboseName,
       category: category ?? this.category,
       rawUrl: url ?? rawUrl,
+      processedUrl: url != null ? getSimplePackageUrl(url) : processedUrl,
       parentId: parentId ?? this.parentId,
       profileMetaData: profileMetaData ?? this.profileMetaData,
     );

packages/devtools_app/test/cpu_profile_model_test.dart

@@ -91,6 +91,36 @@ void main() {
   });
 
   group('CpuStackFrame', () {
+    test('isNative', () {
+      expect(stackFrameA.isNative, isTrue);
+      expect(stackFrameB.isNative, isFalse);
+      expect(stackFrameC.isNative, isFalse);
+      expect(
+        CpuStackFrame(
+          id: CpuProfileData.rootId,
+          name: CpuProfileData.rootName,
+          verboseName: 'all',
+          category: 'Dart',
+          rawUrl: '',
+          parentId: null,
+          profileMetaData: profileMetaData,
+        ).isNative,
+        isFalse,
+      );
+    });
+
+    test('isDartCore', () {
+      expect(stackFrameA.isDartCore, isFalse);
+      expect(stackFrameB.isDartCore, isTrue);
+      expect(stackFrameC.isDartCore, isFalse);
+    });
+
+    test('isFlutterCore', () {
+      expect(stackFrameA.isFlutterCore, isFalse);
+      expect(stackFrameB.isFlutterCore, isFalse);
+      expect(stackFrameC.isFlutterCore, isTrue);
+    });
+
     test('sampleCount', () {
       expect(testStackFrame.inclusiveSampleCount, equals(10));
     });