diff --git a/build/dart/dart_action.gni b/build/dart/dart_action.gni
index 334a09a..0643c87 100644
--- a/build/dart/dart_action.gni
+++ b/build/dart/dart_action.gni
@@ -363,7 +363,7 @@
 #    The arguments to pass to the Dart script.
 #
 #  packages (optional):
-#    The un-rebased path to the .packages file.
+#    The un-rebased path to the package_config.json file.
 #
 #  Forwarded to action() with the usual meaning:
 #    depfile
diff --git a/pkg/_fe_analyzer_shared/pubspec.yaml b/pkg/_fe_analyzer_shared/pubspec.yaml
index 0e1fea0..80c6ed3 100644
--- a/pkg/_fe_analyzer_shared/pubspec.yaml
+++ b/pkg/_fe_analyzer_shared/pubspec.yaml
@@ -1,5 +1,5 @@
 name: _fe_analyzer_shared
-version: 28.0.0
+version: 29.0.0
 description: Logic that is shared between the front_end and analyzer packages.
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/_fe_analyzer_shared
 
diff --git a/pkg/analysis_server/test/client/impl/abstract_client.dart b/pkg/analysis_server/test/client/impl/abstract_client.dart
index caa0386..d067b8d 100644
--- a/pkg/analysis_server/test/client/impl/abstract_client.dart
+++ b/pkg/analysis_server/test/client/impl/abstract_client.dart
@@ -136,7 +136,7 @@
     return response;
   }
 
-  File newFile(String path, String content, [int stamp]);
+  File newFile(String path, String content);
 
   Folder newFolder(String path);
 
diff --git a/pkg/analysis_server/test/client/impl/completion_driver.dart b/pkg/analysis_server/test/client/impl/completion_driver.dart
index 60083d6..bbdeee9 100644
--- a/pkg/analysis_server/test/client/impl/completion_driver.dart
+++ b/pkg/analysis_server/test/client/impl/completion_driver.dart
@@ -131,8 +131,8 @@
   }
 
   @override
-  File newFile(String path, String content, [int? stamp]) => resourceProvider
-      .newFile(resourceProvider.convertPath(path), content, stamp);
+  File newFile(String path, String content) =>
+      resourceProvider.newFile(resourceProvider.convertPath(path), content);
 
   @override
   Folder newFolder(String path) =>
diff --git a/pkg/analyzer/CHANGELOG.md b/pkg/analyzer/CHANGELOG.md
index 1a8d912..a067cd4 100644
--- a/pkg/analyzer/CHANGELOG.md
+++ b/pkg/analyzer/CHANGELOG.md
@@ -1,4 +1,4 @@
-## 2.6.0-dev
+## 2.6.0
 * Deprecated `AnalysisResult.state`, check for specific valid or invalid subtypes.
 * Deprecated `ResultState`.
 * Deprecated `LibraryElement.hasExtUri`, FFI should be used instead.
diff --git a/pkg/analyzer/lib/file_system/file_system.dart b/pkg/analyzer/lib/file_system/file_system.dart
index e71b153..52bb3d7 100644
--- a/pkg/analyzer/lib/file_system/file_system.dart
+++ b/pkg/analyzer/lib/file_system/file_system.dart
@@ -2,6 +2,8 @@
 // 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.
 
+import 'dart:typed_data';
+
 import 'package:analyzer/src/generated/source.dart';
 import 'package:path/path.dart';
 import 'package:watcher/watcher.dart';
@@ -29,7 +31,7 @@
 
   /// Synchronously read the entire file contents as a list of bytes.
   /// Throws a [FileSystemException] if the operation fails.
-  List<int> readAsBytesSync();
+  Uint8List readAsBytesSync();
 
   /// Synchronously read the entire file contents as a [String].
   /// Throws [FileSystemException] if the file does not exist.
diff --git a/pkg/analyzer/lib/file_system/memory_file_system.dart b/pkg/analyzer/lib/file_system/memory_file_system.dart
index 76b90a1..f6d3b10 100644
--- a/pkg/analyzer/lib/file_system/memory_file_system.dart
+++ b/pkg/analyzer/lib/file_system/memory_file_system.dart
@@ -159,21 +159,31 @@
     return link;
   }
 
-  File newFile(String path, String content, [int? stamp]) {
-    var bytes = utf8.encode(content);
+  File newFile(
+    String path,
+    String content, [
+    @Deprecated('This parameter is not used and will be removed') int? stamp,
+  ]) {
+    var bytes = utf8.encode(content) as Uint8List;
+    // ignore: deprecated_member_use_from_same_package
     return newFileWithBytes(path, bytes, stamp);
   }
 
-  File newFileWithBytes(String path, List<int> bytes, [int? stamp]) {
+  File newFileWithBytes(
+    String path,
+    List<int> bytes, [
+    @Deprecated('This parameter is not used and will be removed') int? stamp,
+  ]) {
     _ensureAbsoluteAndNormalized(path);
+    bytes = bytes is Uint8List ? bytes : Uint8List.fromList(bytes);
 
     var parentPath = pathContext.dirname(path);
     var parentData = _newFolder(parentPath);
     _addToParentFolderData(parentData, path);
 
     _pathToData[path] = _FileData(
-      bytes: Uint8List.fromList(bytes),
-      timeStamp: stamp ?? nextStamp++,
+      bytes: bytes,
+      timeStamp: nextStamp++,
     );
     _notifyWatchers(path, ChangeType.ADD);
 
@@ -322,13 +332,13 @@
     return result;
   }
 
-  void _setFileContent(String path, List<int> bytes) {
+  void _setFileContent(String path, Uint8List bytes) {
     var parentPath = pathContext.dirname(path);
     var parentData = _newFolder(parentPath);
     _addToParentFolderData(parentData, path);
 
     _pathToData[path] = _FileData(
-      bytes: Uint8List.fromList(bytes),
+      bytes: bytes,
       timeStamp: nextStamp++,
     );
     _notifyWatchers(path, ChangeType.MODIFY);
@@ -511,12 +521,13 @@
 
   @override
   void writeAsBytesSync(List<int> bytes) {
+    bytes = bytes is Uint8List ? bytes : Uint8List.fromList(bytes);
     provider._setFileContent(path, bytes);
   }
 
   @override
   void writeAsStringSync(String content) {
-    var bytes = utf8.encode(content);
+    var bytes = utf8.encode(content) as Uint8List;
     writeAsBytesSync(bytes);
   }
 }
diff --git a/pkg/analyzer/lib/file_system/overlay_file_system.dart b/pkg/analyzer/lib/file_system/overlay_file_system.dart
index e66c643..dbac07b 100644
--- a/pkg/analyzer/lib/file_system/overlay_file_system.dart
+++ b/pkg/analyzer/lib/file_system/overlay_file_system.dart
@@ -189,7 +189,7 @@
   }
 
   @override
-  List<int> readAsBytesSync() {
+  Uint8List readAsBytesSync() {
     String? content = provider._getOverlayContent(path);
     if (content != null) {
       return utf8.encode(content) as Uint8List;
diff --git a/pkg/analyzer/lib/src/dart/analysis/file_state.dart b/pkg/analyzer/lib/src/dart/analysis/file_state.dart
index 239d1cb..f0f35eb 100644
--- a/pkg/analyzer/lib/src/dart/analysis/file_state.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/file_state.dart
@@ -119,12 +119,8 @@
   String? _content;
   String? _contentHash;
   LineInfo? _lineInfo;
-  Set<String>? _definedClassMemberNames;
-  Set<String>? _definedTopLevelNames;
-  Set<String>? _referencedNames;
   Uint8List? _unlinkedSignature;
   String? _unlinkedKey;
-  String? _informativeKey;
   AnalysisDriverUnlinkedUnit? _driverUnlinkedUnit;
   Uint8List? _apiSignature;
 
@@ -165,14 +161,12 @@
 
   /// The class member names defined by the file.
   Set<String> get definedClassMemberNames {
-    return _definedClassMemberNames ??=
-        _driverUnlinkedUnit!.definedClassMemberNames.toSet();
+    return _driverUnlinkedUnit!.definedClassMemberNames;
   }
 
   /// The top-level names defined by the file.
   Set<String> get definedTopLevelNames {
-    return _definedTopLevelNames ??=
-        _driverUnlinkedUnit!.definedTopLevelNames.toSet();
+    return _driverUnlinkedUnit!.definedTopLevelNames;
   }
 
   /// Return the set of all directly referenced files - imported, exported or
@@ -295,7 +289,7 @@
 
   /// The external names referenced by the file.
   Set<String> get referencedNames {
-    return _referencedNames ??= _driverUnlinkedUnit!.referencedNames.toSet();
+    return _driverUnlinkedUnit!.referencedNames;
   }
 
   @visibleForTesting
@@ -340,16 +334,6 @@
     return other is FileState && other.uri == uri;
   }
 
-  Uint8List getInformativeBytes({CompilationUnit? unit}) {
-    var bytes = _fsState._byteStore.get(_informativeKey!);
-    if (bytes == null) {
-      unit ??= parse();
-      bytes = writeUnitInformative(unit);
-      _fsState._byteStore.put(_informativeKey!, bytes);
-    }
-    return bytes;
-  }
-
   void internal_setLibraryCycle(LibraryCycle? cycle) {
     _libraryCycle = cycle;
   }
@@ -399,9 +383,8 @@
       signature.addBool(_exists!);
       _unlinkedSignature = signature.toByteList();
       var signatureHex = hex.encode(_unlinkedSignature!);
-      _unlinkedKey = '$signatureHex.unlinked2';
       // TODO(scheglov) Use the path as the key, and store the signature.
-      _informativeKey = '$signatureHex.ast';
+      _unlinkedKey = '$signatureHex.unlinked2';
     }
 
     // Prepare the unlinked unit.
@@ -521,11 +504,6 @@
   /// Invalidate any data that depends on the current unlinked data of the file,
   /// because [refresh] is going to recompute the unlinked data.
   void _invalidateCurrentUnresolvedData() {
-    // Invalidate unlinked information.
-    _definedTopLevelNames = null;
-    _definedClassMemberNames = null;
-    _referencedNames = null;
-
     if (_driverUnlinkedUnit != null) {
       for (var name in _driverUnlinkedUnit!.subtypedNames) {
         var files = _fsState._subtypedNameToFiles[name];
@@ -621,6 +599,7 @@
       hasLibraryDirective: hasLibraryDirective,
       hasPartOfDirective: hasPartOfDirective,
       imports: imports,
+      informativeBytes: writeUnitInformative(unit),
       lineStarts: Uint32List.fromList(unit.lineInfo!.lineStarts),
       partOfName: null,
       partOfUri: null,
diff --git a/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart b/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart
index 6278c6f..0c0000f 100644
--- a/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart
@@ -648,17 +648,6 @@
 
     var unitElement = unit.declaredElement as CompilationUnitElementImpl;
 
-    // TODO(scheglov) Hack: set types for top-level variables
-    // Otherwise TypeResolverVisitor will set declared types, and because we
-    // don't run InferStaticVariableTypeTask, we will stuck with these declared
-    // types. And we don't need to run this task - resynthesized elements have
-    // inferred types.
-    for (var e in unitElement.topLevelVariables) {
-      if (!e.isSynthetic) {
-        e.type;
-      }
-    }
-
     unit.accept(
       ResolutionVisitor(
         unitElement: unitElement,
diff --git a/pkg/analyzer/lib/src/dart/analysis/library_context.dart b/pkg/analyzer/lib/src/dart/analysis/library_context.dart
index 7973df8..72092ad 100644
--- a/pkg/analyzer/lib/src/dart/analysis/library_context.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/library_context.dart
@@ -117,7 +117,7 @@
       var unitsInformativeBytes = <Uri, Uint8List>{};
       for (var library in cycle.libraries) {
         for (var file in library.libraryFiles) {
-          unitsInformativeBytes[file.uri] = file.getInformativeBytes();
+          unitsInformativeBytes[file.uri] = file.unlinked2.informativeBytes;
         }
       }
 
diff --git a/pkg/analyzer/lib/src/dart/analysis/unlinked_data.dart b/pkg/analyzer/lib/src/dart/analysis/unlinked_data.dart
index 2c7b78b..5ab1857 100644
--- a/pkg/analyzer/lib/src/dart/analysis/unlinked_data.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/unlinked_data.dart
@@ -153,6 +153,9 @@
   /// URIs of `import` directives.
   final List<UnlinkedNamespaceDirective> imports;
 
+  /// Encoded informative data.
+  final Uint8List informativeBytes;
+
   /// Offsets of the first character of each line in the source code.
   final Uint32List lineStarts;
 
@@ -171,6 +174,7 @@
     required this.hasLibraryDirective,
     required this.hasPartOfDirective,
     required this.imports,
+    required this.informativeBytes,
     required this.lineStarts,
     required this.partOfName,
     required this.partOfUri,
@@ -188,6 +192,7 @@
       imports: reader.readTypedList(
         () => UnlinkedNamespaceDirective.read(reader),
       ),
+      informativeBytes: reader.readUint8List(),
       lineStarts: reader.readUInt30List(),
       partOfName: reader.readOptionalStringUtf8(),
       partOfUri: reader.readOptionalStringUtf8(),
@@ -205,6 +210,7 @@
     sink.writeList<UnlinkedNamespaceDirective>(imports, (x) {
       x.write(sink);
     });
+    sink.writeUint8List(informativeBytes);
     sink.writeUint30List(lineStarts);
     sink.writeOptionalStringUtf8(partOfName);
     sink.writeOptionalStringUtf8(partOfUri);
diff --git a/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart b/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart
index 30be965..90b93ea 100644
--- a/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart
+++ b/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart
@@ -679,17 +679,6 @@
 
     var unitElement = unit.declaredElement as CompilationUnitElementImpl;
 
-    // TODO(scheglov) Hack: set types for top-level variables
-    // Otherwise TypeResolverVisitor will set declared types, and because we
-    // don't run InferStaticVariableTypeTask, we will stuck with these declared
-    // types. And we don't need to run this task - resynthesized elements have
-    // inferred types.
-    for (var e in unitElement.topLevelVariables) {
-      if (!e.isSynthetic) {
-        e.type;
-      }
-    }
-
     unit.accept(
       ResolutionVisitor(
         unitElement: unitElement,
diff --git a/pkg/analyzer/lib/src/dart/micro/library_graph.dart b/pkg/analyzer/lib/src/dart/micro/library_graph.dart
index c1b1c9f..9e6cb1c 100644
--- a/pkg/analyzer/lib/src/dart/micro/library_graph.dart
+++ b/pkg/analyzer/lib/src/dart/micro/library_graph.dart
@@ -15,6 +15,7 @@
 import 'package:analyzer/src/dart/analysis/experiments.dart';
 import 'package:analyzer/src/dart/analysis/feature_set_provider.dart';
 import 'package:analyzer/src/dart/analysis/unlinked_api_signature.dart';
+import 'package:analyzer/src/dart/analysis/unlinked_data.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/micro/cider_byte_store.dart';
 import 'package:analyzer/src/dart/scanner/reader.dart';
@@ -23,10 +24,10 @@
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/summary/api_signature.dart';
-import 'package:analyzer/src/summary/format.dart';
-import 'package:analyzer/src/summary/idl.dart';
 import 'package:analyzer/src/summary/link.dart' as graph
     show DependencyWalker, Node;
+import 'package:analyzer/src/summary2/data_reader.dart';
+import 'package:analyzer/src/summary2/data_writer.dart';
 import 'package:analyzer/src/summary2/informative_data.dart';
 import 'package:analyzer/src/util/file_paths.dart' as file_paths;
 import 'package:analyzer/src/util/performance/operation_performance.dart';
@@ -42,6 +43,74 @@
   libraryWalker.walk(libraryWalker.getNode(file));
 }
 
+class CiderUnitTopLevelDeclarations {
+  final List<String> extensionNames;
+  final List<String> functionNames;
+  final List<String> typeNames;
+  final List<String> variableNames;
+
+  CiderUnitTopLevelDeclarations({
+    required this.extensionNames,
+    required this.functionNames,
+    required this.typeNames,
+    required this.variableNames,
+  });
+
+  factory CiderUnitTopLevelDeclarations.read(SummaryDataReader reader) {
+    return CiderUnitTopLevelDeclarations(
+      extensionNames: reader.readStringUtf8List(),
+      functionNames: reader.readStringUtf8List(),
+      typeNames: reader.readStringUtf8List(),
+      variableNames: reader.readStringUtf8List(),
+    );
+  }
+
+  void write(BufferedSink sink) {
+    sink.writeStringUtf8Iterable(extensionNames);
+    sink.writeStringUtf8Iterable(functionNames);
+    sink.writeStringUtf8Iterable(typeNames);
+    sink.writeStringUtf8Iterable(variableNames);
+  }
+}
+
+class CiderUnlinkedUnit {
+  /// Top-level declarations of the unit.
+  final CiderUnitTopLevelDeclarations topLevelDeclarations;
+
+  /// Unlinked summary of the compilation unit.
+  final UnlinkedUnit unit;
+
+  CiderUnlinkedUnit({
+    required this.topLevelDeclarations,
+    required this.unit,
+  });
+
+  factory CiderUnlinkedUnit.fromBytes(Uint8List bytes) {
+    return CiderUnlinkedUnit.read(
+      SummaryDataReader(bytes),
+    );
+  }
+
+  factory CiderUnlinkedUnit.read(SummaryDataReader reader) {
+    return CiderUnlinkedUnit(
+      topLevelDeclarations: CiderUnitTopLevelDeclarations.read(reader),
+      unit: UnlinkedUnit.read(reader),
+    );
+  }
+
+  Uint8List toBytes() {
+    var byteSink = ByteSink();
+    var sink = BufferedSink(byteSink);
+    write(sink);
+    return sink.flushAndTake();
+  }
+
+  void write(BufferedSink sink) {
+    topLevelDeclarations.write(sink);
+    unit.write(sink);
+  }
+}
+
 class FileState {
   final FileSystemState _fsState;
 
@@ -85,20 +154,12 @@
 
   late Uint8List _digest;
   late bool _exists;
-  late List<int> _apiSignature;
-  late UnlinkedUnit2 unlinked2;
-  late TopLevelDeclarations topLevelDeclarations;
-  Uint8List? informativeBytes;
+  late CiderUnlinkedUnit unlinked;
   LibraryCycle? _libraryCycle;
 
   /// id of the cache entry with unlinked data.
   late int unlinkedId;
 
-  /// id of the cache entry with informative data.
-  /// We use a separate entry because there is no good way to efficiently
-  /// store a raw byte array.
-  late int informativeId;
-
   FileState._(
     this._fsState,
     this.path,
@@ -109,7 +170,7 @@
     this._packageLanguageVersion,
   );
 
-  List<int> get apiSignature => _apiSignature;
+  List<int> get apiSignature => unlinked.unit.apiSignature;
 
   List<int> get digest => _digest;
 
@@ -124,7 +185,7 @@
     return _libraryCycle!;
   }
 
-  LineInfo get lineInfo => LineInfo(unlinked2.lineStarts);
+  LineInfo get lineInfo => LineInfo(unlinked.unit.lineStarts);
 
   /// The resolved signature of the file, that depends on the [libraryCycle]
   /// signature, and the content of the file.
@@ -231,22 +292,15 @@
     });
 
     String unlinkedKey = '$path.unlinked';
-    String informativeKey = '$path.informative';
 
     // Prepare bytes of the unlinked bundle - existing or new.
     // TODO(migration): should not be nullable
     Uint8List? unlinkedBytes;
-    Uint8List? informativeBytes;
     {
       var unlinkedData = _fsState._byteStore.get(unlinkedKey, _digest);
-      var informativeData = _fsState._byteStore.get(informativeKey, _digest);
       unlinkedBytes = unlinkedData?.bytes;
-      informativeBytes = informativeData?.bytes;
 
-      if (unlinkedBytes == null ||
-          unlinkedBytes.isEmpty ||
-          informativeBytes == null ||
-          informativeBytes.isEmpty) {
+      if (unlinkedBytes == null || unlinkedBytes.isEmpty) {
         var content = performance.run('content', (_) {
           return getContent();
         });
@@ -258,48 +312,29 @@
         });
 
         performance.run('unlinked', (performance) {
-          var unlinkedBuilder = serializeAstCiderUnlinked(_digest, unit);
-          unlinkedBytes = unlinkedBuilder.toBuffer();
+          var unlinkedBuilder = serializeAstCiderUnlinked(unit);
+          unlinkedBytes = unlinkedBuilder.toBytes();
           performance.getDataInt('length').add(unlinkedBytes!.length);
           unlinkedData =
               _fsState._byteStore.putGet(unlinkedKey, _digest, unlinkedBytes!);
           unlinkedBytes = unlinkedData!.bytes;
         });
 
-        performance.run('informative', (performance) {
-          informativeBytes = writeUnitInformative(unit);
-          performance.getDataInt('length').add(informativeBytes!.length);
-          informativeData = _fsState._byteStore
-              .putGet(informativeKey, _digest, informativeBytes!);
-          informativeBytes = informativeData!.bytes;
-        });
+        unlinked = CiderUnlinkedUnit.fromBytes(unlinkedBytes!);
 
-        var decoded = CiderUnlinkedUnit.fromBuffer(unlinkedBytes!);
-        unlinked2 = decoded.unlinkedUnit!;
-
-        var unitDeclarations = decoded.topLevelDeclarations!;
-        topLevelDeclarations = TopLevelDeclarations(
-          extensionNames: unitDeclarations.extensionNames.toList(),
-          functionNames: unitDeclarations.functionNames.toList(),
-          typeNames: unitDeclarations.typeNames.toList(),
-          variableNames: unitDeclarations.variableNames.toList(),
-        );
-
+        // TODO(scheglov) We decode above only because we call it here.
         performance.run('prefetch', (_) {
-          _prefetchDirectReferences(unlinked2);
+          _prefetchDirectReferences(unlinked.unit);
         });
       }
       unlinkedId = unlinkedData!.id;
-      informativeId = informativeData!.id;
-      this.informativeBytes = Uint8List.fromList(informativeBytes!);
     }
 
     // Read the unlinked bundle.
-    unlinked2 = CiderUnlinkedUnit.fromBuffer(unlinkedBytes!).unlinkedUnit!;
-    _apiSignature = Uint8List.fromList(unlinked2.apiSignature);
+    unlinked = CiderUnlinkedUnit.fromBytes(unlinkedBytes!);
 
     // Build the graph.
-    for (var directive in unlinked2.imports) {
+    for (var directive in unlinked.unit.imports) {
       var file = _fileForRelativeUri(
         relativeUri: directive.uri,
         performance: performance,
@@ -308,7 +343,7 @@
         importedFiles.add(file);
       }
     }
-    for (var directive in unlinked2.exports) {
+    for (var directive in unlinked.unit.exports) {
       var file = _fileForRelativeUri(
         relativeUri: directive.uri,
         performance: performance,
@@ -317,7 +352,7 @@
         exportedFiles.add(file);
       }
     }
-    for (var uri in unlinked2.parts) {
+    for (var uri in unlinked.unit.parts) {
       var file = _fileForRelativeUri(
         containingLibrary: this,
         relativeUri: uri,
@@ -327,15 +362,15 @@
         partedFiles.add(file);
       }
     }
-    if (unlinked2.hasPartOfDirective) {
+    if (unlinked.unit.hasPartOfDirective) {
       if (containingLibrary == null) {
         _fsState.testView.partsDiscoveredLibraries.add(path);
-        var libraryName = unlinked2.partOfName;
-        var libraryUri = unlinked2.partOfUri;
+        var libraryName = unlinked.unit.partOfName;
+        var libraryUri = unlinked.unit.partOfUri;
         partOfLibrary = null;
-        if (libraryName.isNotEmpty) {
+        if (libraryName != null) {
           _findPartOfNameLibrary(performance: performance);
-        } else if (libraryUri.isNotEmpty) {
+        } else if (libraryUri != null) {
           partOfLibrary = _fileForRelativeUri(
             relativeUri: libraryUri,
             performance: performance,
@@ -424,7 +459,7 @@
     }
   }
 
-  void _prefetchDirectReferences(UnlinkedUnit2 unlinkedUnit2) {
+  void _prefetchDirectReferences(UnlinkedUnit unlinkedUnit2) {
     if (_fsState.prefetchFiles == null) {
       return;
     }
@@ -447,28 +482,27 @@
       }
     }
 
-    for (var directive in unlinked2.imports) {
+    for (var directive in unlinked.unit.imports) {
       findPathForUri(directive.uri);
     }
-    for (var directive in unlinked2.exports) {
+    for (var directive in unlinked.unit.exports) {
       findPathForUri(directive.uri);
     }
-    for (var uri in unlinked2.parts) {
+    for (var uri in unlinked.unit.parts) {
       findPathForUri(uri);
     }
     _fsState.prefetchFiles!(paths.toList());
   }
 
-  static CiderUnlinkedUnitBuilder serializeAstCiderUnlinked(
-      List<int> digest, CompilationUnit unit) {
-    var exports = <UnlinkedNamespaceDirectiveBuilder>[];
-    var imports = <UnlinkedNamespaceDirectiveBuilder>[];
+  static CiderUnlinkedUnit serializeAstCiderUnlinked(CompilationUnit unit) {
+    var exports = <UnlinkedNamespaceDirective>[];
+    var imports = <UnlinkedNamespaceDirective>[];
     var parts = <String>[];
     var hasDartCoreImport = false;
     var hasLibraryDirective = false;
     var hasPartOfDirective = false;
-    var partOfUriStr = '';
-    var partOfName = '';
+    String? partOfName;
+    String? partOfUriStr;
     for (var directive in unit.directives) {
       if (directive is ExportDirective) {
         var builder = _serializeNamespaceDirective(directive);
@@ -497,7 +531,8 @@
     }
     if (!hasDartCoreImport) {
       imports.add(
-        UnlinkedNamespaceDirectiveBuilder(
+        UnlinkedNamespaceDirective(
+          configurations: [],
           uri: 'dart:core',
         ),
       );
@@ -528,21 +563,22 @@
       }
     }
 
-    var unlinkedBuilder = UnlinkedUnit2Builder(
+    var unlinkedUnit = UnlinkedUnit(
       apiSignature: computeUnlinkedApiSignature(unit),
       exports: exports,
-      imports: imports,
-      parts: parts,
       hasLibraryDirective: hasLibraryDirective,
       hasPartOfDirective: hasPartOfDirective,
+      imports: imports,
+      informativeBytes: writeUnitInformative(unit),
+      lineStarts: Uint32List.fromList(unit.lineInfo!.lineStarts),
       partOfName: partOfName,
       partOfUri: partOfUriStr,
-      lineStarts: unit.lineInfo!.lineStarts,
+      parts: parts,
     );
-    return CiderUnlinkedUnitBuilder(
-      contentDigest: digest,
-      unlinkedUnit: unlinkedBuilder,
-      topLevelDeclarations: CiderUnitTopLevelDeclarationsBuilder(
+
+    return CiderUnlinkedUnit(
+      unit: unlinkedUnit,
+      topLevelDeclarations: CiderUnitTopLevelDeclarations(
         extensionNames: declaredExtensions,
         functionNames: declaredFunctions,
         typeNames: declaredTypes,
@@ -551,13 +587,14 @@
     );
   }
 
-  static UnlinkedNamespaceDirectiveBuilder _serializeNamespaceDirective(
-      NamespaceDirective directive) {
-    return UnlinkedNamespaceDirectiveBuilder(
+  static UnlinkedNamespaceDirective _serializeNamespaceDirective(
+    NamespaceDirective directive,
+  ) {
+    return UnlinkedNamespaceDirective(
       configurations: directive.configurations.map((configuration) {
         var name = configuration.name.components.join('.');
         var value = configuration.value?.stringValue ?? '';
-        return UnlinkedNamespaceDirectiveConfigurationBuilder(
+        return UnlinkedNamespaceDirectiveConfiguration(
           name: name,
           value: value,
           uri: configuration.uri.stringValue ?? '',
@@ -638,7 +675,6 @@
     var result = <int>{};
     for (var file in _pathToFile.values) {
       result.add(file.unlinkedId);
-      result.add(file.informativeId);
     }
     return result;
   }
@@ -771,20 +807,21 @@
         }
       }
 
+      var topLevelDeclarations = file.unlinked.topLevelDeclarations;
       addDeclaration(
-        file.topLevelDeclarations.extensionNames,
+        topLevelDeclarations.extensionNames,
         FileTopLevelDeclarationKind.extension,
       );
       addDeclaration(
-        file.topLevelDeclarations.functionNames,
+        topLevelDeclarations.functionNames,
         FileTopLevelDeclarationKind.function,
       );
       addDeclaration(
-        file.topLevelDeclarations.typeNames,
+        topLevelDeclarations.typeNames,
         FileTopLevelDeclarationKind.type,
       );
       addDeclaration(
-        file.topLevelDeclarations.variableNames,
+        topLevelDeclarations.variableNames,
         FileTopLevelDeclarationKind.variable,
       );
     }
@@ -917,26 +954,6 @@
   }
 }
 
-/// Kind of a top-level declaration.
-///
-/// We don't need it to be precise, just enough to support quick fixes.
-enum TopLevelDeclarationKind { type, extension, function, variable }
-
-/// Information about a single top-level declaration.
-class TopLevelDeclarations {
-  final List<String> extensionNames;
-  final List<String> functionNames;
-  final List<String> typeNames;
-  final List<String> variableNames;
-
-  TopLevelDeclarations({
-    required this.extensionNames,
-    required this.functionNames,
-    required this.typeNames,
-    required this.variableNames,
-  });
-}
-
 class _FakeSource implements Source {
   @override
   final String fullName;
diff --git a/pkg/analyzer/lib/src/dart/micro/resolve_file.dart b/pkg/analyzer/lib/src/dart/micro/resolve_file.dart
index f60649d..ab564f3 100644
--- a/pkg/analyzer/lib/src/dart/micro/resolve_file.dart
+++ b/pkg/analyzer/lib/src/dart/micro/resolve_file.dart
@@ -168,7 +168,6 @@
     // Schedule disposing references to cached unlinked data.
     for (var removedFile in removedFiles) {
       removedCacheIds.add(removedFile.unlinkedId);
-      removedCacheIds.add(removedFile.informativeId);
     }
 
     // Remove libraries represented by removed files.
@@ -405,7 +404,6 @@
     var removedFiles = fsState!.removeUnusedFiles(files);
     for (var removedFile in removedFiles) {
       removedCacheIds.add(removedFile.unlinkedId);
-      removedCacheIds.add(removedFile.informativeId);
     }
   }
 
@@ -545,7 +543,7 @@
           file.exists,
           file.getContent(),
           file.lineInfo,
-          file.unlinked2.hasPartOfDirective,
+          file.unlinked.unit.hasPartOfDirective,
           fileResult.unit,
           fileResult.errors,
         );
@@ -825,10 +823,8 @@
       var unitsInformativeBytes = <Uri, Uint8List>{};
       for (var library in cycle.libraries) {
         for (var file in library.libraryFiles) {
-          var informativeBytes = file.informativeBytes;
-          if (informativeBytes != null) {
-            unitsInformativeBytes[file.uri] = informativeBytes;
-          }
+          var informativeBytes = file.unlinked.unit.informativeBytes;
+          unitsInformativeBytes[file.uri] = informativeBytes;
         }
       }
 
@@ -856,7 +852,7 @@
 
             String? partUriStr;
             if (partIndex >= 0) {
-              partUriStr = libraryFile.unlinked2.parts[partIndex];
+              partUriStr = libraryFile.unlinked.unit.parts[partIndex];
             }
             partIndex++;
 
diff --git a/pkg/analyzer/lib/src/summary/format.dart b/pkg/analyzer/lib/src/summary/format.dart
index 9e2e91b..e85a569 100644
--- a/pkg/analyzer/lib/src/summary/format.dart
+++ b/pkg/analyzer/lib/src/summary/format.dart
@@ -3363,395 +3363,6 @@
   String toString() => convert.json.encode(toJson());
 }
 
-class CiderUnitTopLevelDeclarationsBuilder extends Object
-    with _CiderUnitTopLevelDeclarationsMixin
-    implements idl.CiderUnitTopLevelDeclarations {
-  List<String>? _extensionNames;
-  List<String>? _functionNames;
-  List<String>? _typeNames;
-  List<String>? _variableNames;
-
-  @override
-  List<String> get extensionNames => _extensionNames ??= <String>[];
-
-  set extensionNames(List<String> value) {
-    this._extensionNames = value;
-  }
-
-  @override
-  List<String> get functionNames => _functionNames ??= <String>[];
-
-  set functionNames(List<String> value) {
-    this._functionNames = value;
-  }
-
-  @override
-  List<String> get typeNames => _typeNames ??= <String>[];
-
-  set typeNames(List<String> value) {
-    this._typeNames = value;
-  }
-
-  @override
-  List<String> get variableNames => _variableNames ??= <String>[];
-
-  set variableNames(List<String> value) {
-    this._variableNames = value;
-  }
-
-  CiderUnitTopLevelDeclarationsBuilder(
-      {List<String>? extensionNames,
-      List<String>? functionNames,
-      List<String>? typeNames,
-      List<String>? variableNames})
-      : _extensionNames = extensionNames,
-        _functionNames = functionNames,
-        _typeNames = typeNames,
-        _variableNames = variableNames;
-
-  /// Flush [informative] data recursively.
-  void flushInformative() {}
-
-  /// Accumulate non-[informative] data into [signature].
-  void collectApiSignature(api_sig.ApiSignature signatureSink) {
-    var extensionNames = this._extensionNames;
-    if (extensionNames == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(extensionNames.length);
-      for (var x in extensionNames) {
-        signatureSink.addString(x);
-      }
-    }
-    var functionNames = this._functionNames;
-    if (functionNames == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(functionNames.length);
-      for (var x in functionNames) {
-        signatureSink.addString(x);
-      }
-    }
-    var typeNames = this._typeNames;
-    if (typeNames == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(typeNames.length);
-      for (var x in typeNames) {
-        signatureSink.addString(x);
-      }
-    }
-    var variableNames = this._variableNames;
-    if (variableNames == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(variableNames.length);
-      for (var x in variableNames) {
-        signatureSink.addString(x);
-      }
-    }
-  }
-
-  fb.Offset finish(fb.Builder fbBuilder) {
-    fb.Offset? offset_extensionNames;
-    fb.Offset? offset_functionNames;
-    fb.Offset? offset_typeNames;
-    fb.Offset? offset_variableNames;
-    var extensionNames = _extensionNames;
-    if (!(extensionNames == null || extensionNames.isEmpty)) {
-      offset_extensionNames = fbBuilder.writeList(
-          extensionNames.map((b) => fbBuilder.writeString(b)).toList());
-    }
-    var functionNames = _functionNames;
-    if (!(functionNames == null || functionNames.isEmpty)) {
-      offset_functionNames = fbBuilder.writeList(
-          functionNames.map((b) => fbBuilder.writeString(b)).toList());
-    }
-    var typeNames = _typeNames;
-    if (!(typeNames == null || typeNames.isEmpty)) {
-      offset_typeNames = fbBuilder
-          .writeList(typeNames.map((b) => fbBuilder.writeString(b)).toList());
-    }
-    var variableNames = _variableNames;
-    if (!(variableNames == null || variableNames.isEmpty)) {
-      offset_variableNames = fbBuilder.writeList(
-          variableNames.map((b) => fbBuilder.writeString(b)).toList());
-    }
-    fbBuilder.startTable();
-    if (offset_extensionNames != null) {
-      fbBuilder.addOffset(0, offset_extensionNames);
-    }
-    if (offset_functionNames != null) {
-      fbBuilder.addOffset(1, offset_functionNames);
-    }
-    if (offset_typeNames != null) {
-      fbBuilder.addOffset(2, offset_typeNames);
-    }
-    if (offset_variableNames != null) {
-      fbBuilder.addOffset(3, offset_variableNames);
-    }
-    return fbBuilder.endTable();
-  }
-}
-
-class _CiderUnitTopLevelDeclarationsReader
-    extends fb.TableReader<_CiderUnitTopLevelDeclarationsImpl> {
-  const _CiderUnitTopLevelDeclarationsReader();
-
-  @override
-  _CiderUnitTopLevelDeclarationsImpl createObject(
-          fb.BufferContext bc, int offset) =>
-      _CiderUnitTopLevelDeclarationsImpl(bc, offset);
-}
-
-class _CiderUnitTopLevelDeclarationsImpl extends Object
-    with _CiderUnitTopLevelDeclarationsMixin
-    implements idl.CiderUnitTopLevelDeclarations {
-  final fb.BufferContext _bc;
-  final int _bcOffset;
-
-  _CiderUnitTopLevelDeclarationsImpl(this._bc, this._bcOffset);
-
-  List<String>? _extensionNames;
-  List<String>? _functionNames;
-  List<String>? _typeNames;
-  List<String>? _variableNames;
-
-  @override
-  List<String> get extensionNames {
-    return _extensionNames ??= const fb.ListReader<String>(fb.StringReader())
-        .vTableGet(_bc, _bcOffset, 0, const <String>[]);
-  }
-
-  @override
-  List<String> get functionNames {
-    return _functionNames ??= const fb.ListReader<String>(fb.StringReader())
-        .vTableGet(_bc, _bcOffset, 1, const <String>[]);
-  }
-
-  @override
-  List<String> get typeNames {
-    return _typeNames ??= const fb.ListReader<String>(fb.StringReader())
-        .vTableGet(_bc, _bcOffset, 2, const <String>[]);
-  }
-
-  @override
-  List<String> get variableNames {
-    return _variableNames ??= const fb.ListReader<String>(fb.StringReader())
-        .vTableGet(_bc, _bcOffset, 3, const <String>[]);
-  }
-}
-
-abstract class _CiderUnitTopLevelDeclarationsMixin
-    implements idl.CiderUnitTopLevelDeclarations {
-  @override
-  Map<String, Object> toJson() {
-    Map<String, Object> _result = <String, Object>{};
-    var local_extensionNames = extensionNames;
-    if (local_extensionNames.isNotEmpty) {
-      _result["extensionNames"] = local_extensionNames;
-    }
-    var local_functionNames = functionNames;
-    if (local_functionNames.isNotEmpty) {
-      _result["functionNames"] = local_functionNames;
-    }
-    var local_typeNames = typeNames;
-    if (local_typeNames.isNotEmpty) {
-      _result["typeNames"] = local_typeNames;
-    }
-    var local_variableNames = variableNames;
-    if (local_variableNames.isNotEmpty) {
-      _result["variableNames"] = local_variableNames;
-    }
-    return _result;
-  }
-
-  @override
-  Map<String, Object?> toMap() => {
-        "extensionNames": extensionNames,
-        "functionNames": functionNames,
-        "typeNames": typeNames,
-        "variableNames": variableNames,
-      };
-
-  @override
-  String toString() => convert.json.encode(toJson());
-}
-
-class CiderUnlinkedUnitBuilder extends Object
-    with _CiderUnlinkedUnitMixin
-    implements idl.CiderUnlinkedUnit {
-  List<int>? _contentDigest;
-  CiderUnitTopLevelDeclarationsBuilder? _topLevelDeclarations;
-  UnlinkedUnit2Builder? _unlinkedUnit;
-
-  @override
-  List<int> get contentDigest => _contentDigest ??= <int>[];
-
-  /// The hash signature of the contents of the file.
-  set contentDigest(List<int> value) {
-    assert(value.every((e) => e >= 0));
-    this._contentDigest = value;
-  }
-
-  @override
-  CiderUnitTopLevelDeclarationsBuilder? get topLevelDeclarations =>
-      _topLevelDeclarations;
-
-  /// Top-level declarations of the unit.
-  set topLevelDeclarations(CiderUnitTopLevelDeclarationsBuilder? value) {
-    this._topLevelDeclarations = value;
-  }
-
-  @override
-  UnlinkedUnit2Builder? get unlinkedUnit => _unlinkedUnit;
-
-  /// Unlinked summary of the compilation unit.
-  set unlinkedUnit(UnlinkedUnit2Builder? value) {
-    this._unlinkedUnit = value;
-  }
-
-  CiderUnlinkedUnitBuilder(
-      {List<int>? contentDigest,
-      CiderUnitTopLevelDeclarationsBuilder? topLevelDeclarations,
-      UnlinkedUnit2Builder? unlinkedUnit})
-      : _contentDigest = contentDigest,
-        _topLevelDeclarations = topLevelDeclarations,
-        _unlinkedUnit = unlinkedUnit;
-
-  /// Flush [informative] data recursively.
-  void flushInformative() {
-    _topLevelDeclarations?.flushInformative();
-    _unlinkedUnit?.flushInformative();
-  }
-
-  /// Accumulate non-[informative] data into [signature].
-  void collectApiSignature(api_sig.ApiSignature signatureSink) {
-    var contentDigest = this._contentDigest;
-    if (contentDigest == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(contentDigest.length);
-      for (var x in contentDigest) {
-        signatureSink.addInt(x);
-      }
-    }
-    signatureSink.addBool(this._topLevelDeclarations != null);
-    this._topLevelDeclarations?.collectApiSignature(signatureSink);
-    signatureSink.addBool(this._unlinkedUnit != null);
-    this._unlinkedUnit?.collectApiSignature(signatureSink);
-  }
-
-  typed_data.Uint8List toBuffer() {
-    fb.Builder fbBuilder = fb.Builder();
-    return fbBuilder.finish(finish(fbBuilder), "CUUN");
-  }
-
-  fb.Offset finish(fb.Builder fbBuilder) {
-    fb.Offset? offset_contentDigest;
-    fb.Offset? offset_topLevelDeclarations;
-    fb.Offset? offset_unlinkedUnit;
-    var contentDigest = _contentDigest;
-    if (!(contentDigest == null || contentDigest.isEmpty)) {
-      offset_contentDigest = fbBuilder.writeListUint32(contentDigest);
-    }
-    var topLevelDeclarations = _topLevelDeclarations;
-    if (topLevelDeclarations != null) {
-      offset_topLevelDeclarations = topLevelDeclarations.finish(fbBuilder);
-    }
-    var unlinkedUnit = _unlinkedUnit;
-    if (unlinkedUnit != null) {
-      offset_unlinkedUnit = unlinkedUnit.finish(fbBuilder);
-    }
-    fbBuilder.startTable();
-    if (offset_contentDigest != null) {
-      fbBuilder.addOffset(0, offset_contentDigest);
-    }
-    if (offset_topLevelDeclarations != null) {
-      fbBuilder.addOffset(1, offset_topLevelDeclarations);
-    }
-    if (offset_unlinkedUnit != null) {
-      fbBuilder.addOffset(2, offset_unlinkedUnit);
-    }
-    return fbBuilder.endTable();
-  }
-}
-
-idl.CiderUnlinkedUnit readCiderUnlinkedUnit(List<int> buffer) {
-  fb.BufferContext rootRef = fb.BufferContext.fromBytes(buffer);
-  return const _CiderUnlinkedUnitReader().read(rootRef, 0);
-}
-
-class _CiderUnlinkedUnitReader extends fb.TableReader<_CiderUnlinkedUnitImpl> {
-  const _CiderUnlinkedUnitReader();
-
-  @override
-  _CiderUnlinkedUnitImpl createObject(fb.BufferContext bc, int offset) =>
-      _CiderUnlinkedUnitImpl(bc, offset);
-}
-
-class _CiderUnlinkedUnitImpl extends Object
-    with _CiderUnlinkedUnitMixin
-    implements idl.CiderUnlinkedUnit {
-  final fb.BufferContext _bc;
-  final int _bcOffset;
-
-  _CiderUnlinkedUnitImpl(this._bc, this._bcOffset);
-
-  List<int>? _contentDigest;
-  idl.CiderUnitTopLevelDeclarations? _topLevelDeclarations;
-  idl.UnlinkedUnit2? _unlinkedUnit;
-
-  @override
-  List<int> get contentDigest {
-    return _contentDigest ??=
-        const fb.Uint32ListReader().vTableGet(_bc, _bcOffset, 0, const <int>[]);
-  }
-
-  @override
-  idl.CiderUnitTopLevelDeclarations? get topLevelDeclarations {
-    return _topLevelDeclarations ??=
-        const _CiderUnitTopLevelDeclarationsReader()
-            .vTableGetOrNull(_bc, _bcOffset, 1);
-  }
-
-  @override
-  idl.UnlinkedUnit2? get unlinkedUnit {
-    return _unlinkedUnit ??=
-        const _UnlinkedUnit2Reader().vTableGetOrNull(_bc, _bcOffset, 2);
-  }
-}
-
-abstract class _CiderUnlinkedUnitMixin implements idl.CiderUnlinkedUnit {
-  @override
-  Map<String, Object> toJson() {
-    Map<String, Object> _result = <String, Object>{};
-    var local_contentDigest = contentDigest;
-    if (local_contentDigest.isNotEmpty) {
-      _result["contentDigest"] = local_contentDigest;
-    }
-    var local_topLevelDeclarations = topLevelDeclarations;
-    if (local_topLevelDeclarations != null) {
-      _result["topLevelDeclarations"] = local_topLevelDeclarations.toJson();
-    }
-    var local_unlinkedUnit = unlinkedUnit;
-    if (local_unlinkedUnit != null) {
-      _result["unlinkedUnit"] = local_unlinkedUnit.toJson();
-    }
-    return _result;
-  }
-
-  @override
-  Map<String, Object?> toMap() => {
-        "contentDigest": contentDigest,
-        "topLevelDeclarations": topLevelDeclarations,
-        "unlinkedUnit": unlinkedUnit,
-      };
-
-  @override
-  String toString() => convert.json.encode(toJson());
-}
-
 class DiagnosticMessageBuilder extends Object
     with _DiagnosticMessageMixin
     implements idl.DiagnosticMessage {
@@ -4167,669 +3778,3 @@
   @override
   String toString() => convert.json.encode(toJson());
 }
-
-class UnlinkedNamespaceDirectiveBuilder extends Object
-    with _UnlinkedNamespaceDirectiveMixin
-    implements idl.UnlinkedNamespaceDirective {
-  List<UnlinkedNamespaceDirectiveConfigurationBuilder>? _configurations;
-  String? _uri;
-
-  @override
-  List<UnlinkedNamespaceDirectiveConfigurationBuilder> get configurations =>
-      _configurations ??= <UnlinkedNamespaceDirectiveConfigurationBuilder>[];
-
-  /// The configurations that control which library will actually be used.
-  set configurations(
-      List<UnlinkedNamespaceDirectiveConfigurationBuilder> value) {
-    this._configurations = value;
-  }
-
-  @override
-  String get uri => _uri ??= '';
-
-  /// The URI referenced by this directive, nad used by default when none
-  /// of the [configurations] matches.
-  set uri(String value) {
-    this._uri = value;
-  }
-
-  UnlinkedNamespaceDirectiveBuilder(
-      {List<UnlinkedNamespaceDirectiveConfigurationBuilder>? configurations,
-      String? uri})
-      : _configurations = configurations,
-        _uri = uri;
-
-  /// Flush [informative] data recursively.
-  void flushInformative() {
-    _configurations?.forEach((b) => b.flushInformative());
-  }
-
-  /// Accumulate non-[informative] data into [signature].
-  void collectApiSignature(api_sig.ApiSignature signatureSink) {
-    var configurations = this._configurations;
-    if (configurations == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(configurations.length);
-      for (var x in configurations) {
-        x.collectApiSignature(signatureSink);
-      }
-    }
-    signatureSink.addString(this._uri ?? '');
-  }
-
-  fb.Offset finish(fb.Builder fbBuilder) {
-    fb.Offset? offset_configurations;
-    fb.Offset? offset_uri;
-    var configurations = _configurations;
-    if (!(configurations == null || configurations.isEmpty)) {
-      offset_configurations = fbBuilder
-          .writeList(configurations.map((b) => b.finish(fbBuilder)).toList());
-    }
-    var uri = _uri;
-    if (uri != null) {
-      offset_uri = fbBuilder.writeString(uri);
-    }
-    fbBuilder.startTable();
-    if (offset_configurations != null) {
-      fbBuilder.addOffset(0, offset_configurations);
-    }
-    if (offset_uri != null) {
-      fbBuilder.addOffset(1, offset_uri);
-    }
-    return fbBuilder.endTable();
-  }
-}
-
-class _UnlinkedNamespaceDirectiveReader
-    extends fb.TableReader<_UnlinkedNamespaceDirectiveImpl> {
-  const _UnlinkedNamespaceDirectiveReader();
-
-  @override
-  _UnlinkedNamespaceDirectiveImpl createObject(
-          fb.BufferContext bc, int offset) =>
-      _UnlinkedNamespaceDirectiveImpl(bc, offset);
-}
-
-class _UnlinkedNamespaceDirectiveImpl extends Object
-    with _UnlinkedNamespaceDirectiveMixin
-    implements idl.UnlinkedNamespaceDirective {
-  final fb.BufferContext _bc;
-  final int _bcOffset;
-
-  _UnlinkedNamespaceDirectiveImpl(this._bc, this._bcOffset);
-
-  List<idl.UnlinkedNamespaceDirectiveConfiguration>? _configurations;
-  String? _uri;
-
-  @override
-  List<idl.UnlinkedNamespaceDirectiveConfiguration> get configurations {
-    return _configurations ??=
-        const fb.ListReader<idl.UnlinkedNamespaceDirectiveConfiguration>(
-                _UnlinkedNamespaceDirectiveConfigurationReader())
-            .vTableGet(_bc, _bcOffset, 0,
-                const <idl.UnlinkedNamespaceDirectiveConfiguration>[]);
-  }
-
-  @override
-  String get uri {
-    return _uri ??= const fb.StringReader().vTableGet(_bc, _bcOffset, 1, '');
-  }
-}
-
-abstract class _UnlinkedNamespaceDirectiveMixin
-    implements idl.UnlinkedNamespaceDirective {
-  @override
-  Map<String, Object> toJson() {
-    Map<String, Object> _result = <String, Object>{};
-    var local_configurations = configurations;
-    if (local_configurations.isNotEmpty) {
-      _result["configurations"] =
-          local_configurations.map((_value) => _value.toJson()).toList();
-    }
-    var local_uri = uri;
-    if (local_uri != '') {
-      _result["uri"] = local_uri;
-    }
-    return _result;
-  }
-
-  @override
-  Map<String, Object?> toMap() => {
-        "configurations": configurations,
-        "uri": uri,
-      };
-
-  @override
-  String toString() => convert.json.encode(toJson());
-}
-
-class UnlinkedNamespaceDirectiveConfigurationBuilder extends Object
-    with _UnlinkedNamespaceDirectiveConfigurationMixin
-    implements idl.UnlinkedNamespaceDirectiveConfiguration {
-  String? _name;
-  String? _uri;
-  String? _value;
-
-  @override
-  String get name => _name ??= '';
-
-  /// The name of the declared variable used in the condition.
-  set name(String value) {
-    this._name = value;
-  }
-
-  @override
-  String get uri => _uri ??= '';
-
-  /// The URI to be used if the condition is true.
-  set uri(String value) {
-    this._uri = value;
-  }
-
-  @override
-  String get value => _value ??= '';
-
-  /// The value to which the value of the declared variable will be compared,
-  /// or the empty string if the condition does not include an equality test.
-  set value(String value) {
-    this._value = value;
-  }
-
-  UnlinkedNamespaceDirectiveConfigurationBuilder(
-      {String? name, String? uri, String? value})
-      : _name = name,
-        _uri = uri,
-        _value = value;
-
-  /// Flush [informative] data recursively.
-  void flushInformative() {}
-
-  /// Accumulate non-[informative] data into [signature].
-  void collectApiSignature(api_sig.ApiSignature signatureSink) {
-    signatureSink.addString(this._name ?? '');
-    signatureSink.addString(this._value ?? '');
-    signatureSink.addString(this._uri ?? '');
-  }
-
-  fb.Offset finish(fb.Builder fbBuilder) {
-    fb.Offset? offset_name;
-    fb.Offset? offset_uri;
-    fb.Offset? offset_value;
-    var name = _name;
-    if (name != null) {
-      offset_name = fbBuilder.writeString(name);
-    }
-    var uri = _uri;
-    if (uri != null) {
-      offset_uri = fbBuilder.writeString(uri);
-    }
-    var value = _value;
-    if (value != null) {
-      offset_value = fbBuilder.writeString(value);
-    }
-    fbBuilder.startTable();
-    if (offset_name != null) {
-      fbBuilder.addOffset(0, offset_name);
-    }
-    if (offset_uri != null) {
-      fbBuilder.addOffset(2, offset_uri);
-    }
-    if (offset_value != null) {
-      fbBuilder.addOffset(1, offset_value);
-    }
-    return fbBuilder.endTable();
-  }
-}
-
-class _UnlinkedNamespaceDirectiveConfigurationReader
-    extends fb.TableReader<_UnlinkedNamespaceDirectiveConfigurationImpl> {
-  const _UnlinkedNamespaceDirectiveConfigurationReader();
-
-  @override
-  _UnlinkedNamespaceDirectiveConfigurationImpl createObject(
-          fb.BufferContext bc, int offset) =>
-      _UnlinkedNamespaceDirectiveConfigurationImpl(bc, offset);
-}
-
-class _UnlinkedNamespaceDirectiveConfigurationImpl extends Object
-    with _UnlinkedNamespaceDirectiveConfigurationMixin
-    implements idl.UnlinkedNamespaceDirectiveConfiguration {
-  final fb.BufferContext _bc;
-  final int _bcOffset;
-
-  _UnlinkedNamespaceDirectiveConfigurationImpl(this._bc, this._bcOffset);
-
-  String? _name;
-  String? _uri;
-  String? _value;
-
-  @override
-  String get name {
-    return _name ??= const fb.StringReader().vTableGet(_bc, _bcOffset, 0, '');
-  }
-
-  @override
-  String get uri {
-    return _uri ??= const fb.StringReader().vTableGet(_bc, _bcOffset, 2, '');
-  }
-
-  @override
-  String get value {
-    return _value ??= const fb.StringReader().vTableGet(_bc, _bcOffset, 1, '');
-  }
-}
-
-abstract class _UnlinkedNamespaceDirectiveConfigurationMixin
-    implements idl.UnlinkedNamespaceDirectiveConfiguration {
-  @override
-  Map<String, Object> toJson() {
-    Map<String, Object> _result = <String, Object>{};
-    var local_name = name;
-    if (local_name != '') {
-      _result["name"] = local_name;
-    }
-    var local_uri = uri;
-    if (local_uri != '') {
-      _result["uri"] = local_uri;
-    }
-    var local_value = value;
-    if (local_value != '') {
-      _result["value"] = local_value;
-    }
-    return _result;
-  }
-
-  @override
-  Map<String, Object?> toMap() => {
-        "name": name,
-        "uri": uri,
-        "value": value,
-      };
-
-  @override
-  String toString() => convert.json.encode(toJson());
-}
-
-class UnlinkedUnit2Builder extends Object
-    with _UnlinkedUnit2Mixin
-    implements idl.UnlinkedUnit2 {
-  List<int>? _apiSignature;
-  List<UnlinkedNamespaceDirectiveBuilder>? _exports;
-  bool? _hasLibraryDirective;
-  bool? _hasPartOfDirective;
-  List<UnlinkedNamespaceDirectiveBuilder>? _imports;
-  List<int>? _lineStarts;
-  String? _partOfName;
-  String? _partOfUri;
-  List<String>? _parts;
-
-  @override
-  List<int> get apiSignature => _apiSignature ??= <int>[];
-
-  /// The MD5 hash signature of the API portion of this unit. It depends on all
-  /// tokens that might affect APIs of declarations in the unit.
-  set apiSignature(List<int> value) {
-    assert(value.every((e) => e >= 0));
-    this._apiSignature = value;
-  }
-
-  @override
-  List<UnlinkedNamespaceDirectiveBuilder> get exports =>
-      _exports ??= <UnlinkedNamespaceDirectiveBuilder>[];
-
-  /// URIs of `export` directives.
-  set exports(List<UnlinkedNamespaceDirectiveBuilder> value) {
-    this._exports = value;
-  }
-
-  @override
-  bool get hasLibraryDirective => _hasLibraryDirective ??= false;
-
-  /// Is `true` if the unit contains a `library` directive.
-  set hasLibraryDirective(bool value) {
-    this._hasLibraryDirective = value;
-  }
-
-  @override
-  bool get hasPartOfDirective => _hasPartOfDirective ??= false;
-
-  /// Is `true` if the unit contains a `part of` directive.
-  set hasPartOfDirective(bool value) {
-    this._hasPartOfDirective = value;
-  }
-
-  @override
-  List<UnlinkedNamespaceDirectiveBuilder> get imports =>
-      _imports ??= <UnlinkedNamespaceDirectiveBuilder>[];
-
-  /// URIs of `import` directives.
-  set imports(List<UnlinkedNamespaceDirectiveBuilder> value) {
-    this._imports = value;
-  }
-
-  @override
-  List<int> get lineStarts => _lineStarts ??= <int>[];
-
-  /// Offsets of the first character of each line in the source code.
-  set lineStarts(List<int> value) {
-    assert(value.every((e) => e >= 0));
-    this._lineStarts = value;
-  }
-
-  @override
-  String get partOfName => _partOfName ??= '';
-
-  /// The library name of the `part of my.name;` directive.
-  set partOfName(String value) {
-    this._partOfName = value;
-  }
-
-  @override
-  String get partOfUri => _partOfUri ??= '';
-
-  /// URI of the `part of 'uri';` directive.
-  set partOfUri(String value) {
-    this._partOfUri = value;
-  }
-
-  @override
-  List<String> get parts => _parts ??= <String>[];
-
-  /// URIs of `part` directives.
-  set parts(List<String> value) {
-    this._parts = value;
-  }
-
-  UnlinkedUnit2Builder(
-      {List<int>? apiSignature,
-      List<UnlinkedNamespaceDirectiveBuilder>? exports,
-      bool? hasLibraryDirective,
-      bool? hasPartOfDirective,
-      List<UnlinkedNamespaceDirectiveBuilder>? imports,
-      List<int>? lineStarts,
-      String? partOfName,
-      String? partOfUri,
-      List<String>? parts})
-      : _apiSignature = apiSignature,
-        _exports = exports,
-        _hasLibraryDirective = hasLibraryDirective,
-        _hasPartOfDirective = hasPartOfDirective,
-        _imports = imports,
-        _lineStarts = lineStarts,
-        _partOfName = partOfName,
-        _partOfUri = partOfUri,
-        _parts = parts;
-
-  /// Flush [informative] data recursively.
-  void flushInformative() {
-    _exports?.forEach((b) => b.flushInformative());
-    _imports?.forEach((b) => b.flushInformative());
-    _lineStarts = null;
-  }
-
-  /// Accumulate non-[informative] data into [signature].
-  void collectApiSignature(api_sig.ApiSignature signatureSink) {
-    var apiSignature = this._apiSignature;
-    if (apiSignature == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(apiSignature.length);
-      for (var x in apiSignature) {
-        signatureSink.addInt(x);
-      }
-    }
-    var exports = this._exports;
-    if (exports == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(exports.length);
-      for (var x in exports) {
-        x.collectApiSignature(signatureSink);
-      }
-    }
-    var imports = this._imports;
-    if (imports == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(imports.length);
-      for (var x in imports) {
-        x.collectApiSignature(signatureSink);
-      }
-    }
-    signatureSink.addBool(this._hasPartOfDirective == true);
-    var parts = this._parts;
-    if (parts == null) {
-      signatureSink.addInt(0);
-    } else {
-      signatureSink.addInt(parts.length);
-      for (var x in parts) {
-        signatureSink.addString(x);
-      }
-    }
-    signatureSink.addBool(this._hasLibraryDirective == true);
-    signatureSink.addString(this._partOfUri ?? '');
-    signatureSink.addString(this._partOfName ?? '');
-  }
-
-  typed_data.Uint8List toBuffer() {
-    fb.Builder fbBuilder = fb.Builder();
-    return fbBuilder.finish(finish(fbBuilder), "UUN2");
-  }
-
-  fb.Offset finish(fb.Builder fbBuilder) {
-    fb.Offset? offset_apiSignature;
-    fb.Offset? offset_exports;
-    fb.Offset? offset_imports;
-    fb.Offset? offset_lineStarts;
-    fb.Offset? offset_partOfName;
-    fb.Offset? offset_partOfUri;
-    fb.Offset? offset_parts;
-    var apiSignature = _apiSignature;
-    if (!(apiSignature == null || apiSignature.isEmpty)) {
-      offset_apiSignature = fbBuilder.writeListUint32(apiSignature);
-    }
-    var exports = _exports;
-    if (!(exports == null || exports.isEmpty)) {
-      offset_exports =
-          fbBuilder.writeList(exports.map((b) => b.finish(fbBuilder)).toList());
-    }
-    var imports = _imports;
-    if (!(imports == null || imports.isEmpty)) {
-      offset_imports =
-          fbBuilder.writeList(imports.map((b) => b.finish(fbBuilder)).toList());
-    }
-    var lineStarts = _lineStarts;
-    if (!(lineStarts == null || lineStarts.isEmpty)) {
-      offset_lineStarts = fbBuilder.writeListUint32(lineStarts);
-    }
-    var partOfName = _partOfName;
-    if (partOfName != null) {
-      offset_partOfName = fbBuilder.writeString(partOfName);
-    }
-    var partOfUri = _partOfUri;
-    if (partOfUri != null) {
-      offset_partOfUri = fbBuilder.writeString(partOfUri);
-    }
-    var parts = _parts;
-    if (!(parts == null || parts.isEmpty)) {
-      offset_parts = fbBuilder
-          .writeList(parts.map((b) => fbBuilder.writeString(b)).toList());
-    }
-    fbBuilder.startTable();
-    if (offset_apiSignature != null) {
-      fbBuilder.addOffset(0, offset_apiSignature);
-    }
-    if (offset_exports != null) {
-      fbBuilder.addOffset(1, offset_exports);
-    }
-    fbBuilder.addBool(6, _hasLibraryDirective == true);
-    fbBuilder.addBool(3, _hasPartOfDirective == true);
-    if (offset_imports != null) {
-      fbBuilder.addOffset(2, offset_imports);
-    }
-    if (offset_lineStarts != null) {
-      fbBuilder.addOffset(5, offset_lineStarts);
-    }
-    if (offset_partOfName != null) {
-      fbBuilder.addOffset(8, offset_partOfName);
-    }
-    if (offset_partOfUri != null) {
-      fbBuilder.addOffset(7, offset_partOfUri);
-    }
-    if (offset_parts != null) {
-      fbBuilder.addOffset(4, offset_parts);
-    }
-    return fbBuilder.endTable();
-  }
-}
-
-idl.UnlinkedUnit2 readUnlinkedUnit2(List<int> buffer) {
-  fb.BufferContext rootRef = fb.BufferContext.fromBytes(buffer);
-  return const _UnlinkedUnit2Reader().read(rootRef, 0);
-}
-
-class _UnlinkedUnit2Reader extends fb.TableReader<_UnlinkedUnit2Impl> {
-  const _UnlinkedUnit2Reader();
-
-  @override
-  _UnlinkedUnit2Impl createObject(fb.BufferContext bc, int offset) =>
-      _UnlinkedUnit2Impl(bc, offset);
-}
-
-class _UnlinkedUnit2Impl extends Object
-    with _UnlinkedUnit2Mixin
-    implements idl.UnlinkedUnit2 {
-  final fb.BufferContext _bc;
-  final int _bcOffset;
-
-  _UnlinkedUnit2Impl(this._bc, this._bcOffset);
-
-  List<int>? _apiSignature;
-  List<idl.UnlinkedNamespaceDirective>? _exports;
-  bool? _hasLibraryDirective;
-  bool? _hasPartOfDirective;
-  List<idl.UnlinkedNamespaceDirective>? _imports;
-  List<int>? _lineStarts;
-  String? _partOfName;
-  String? _partOfUri;
-  List<String>? _parts;
-
-  @override
-  List<int> get apiSignature {
-    return _apiSignature ??=
-        const fb.Uint32ListReader().vTableGet(_bc, _bcOffset, 0, const <int>[]);
-  }
-
-  @override
-  List<idl.UnlinkedNamespaceDirective> get exports {
-    return _exports ??= const fb.ListReader<idl.UnlinkedNamespaceDirective>(
-            _UnlinkedNamespaceDirectiveReader())
-        .vTableGet(_bc, _bcOffset, 1, const <idl.UnlinkedNamespaceDirective>[]);
-  }
-
-  @override
-  bool get hasLibraryDirective {
-    return _hasLibraryDirective ??=
-        const fb.BoolReader().vTableGet(_bc, _bcOffset, 6, false);
-  }
-
-  @override
-  bool get hasPartOfDirective {
-    return _hasPartOfDirective ??=
-        const fb.BoolReader().vTableGet(_bc, _bcOffset, 3, false);
-  }
-
-  @override
-  List<idl.UnlinkedNamespaceDirective> get imports {
-    return _imports ??= const fb.ListReader<idl.UnlinkedNamespaceDirective>(
-            _UnlinkedNamespaceDirectiveReader())
-        .vTableGet(_bc, _bcOffset, 2, const <idl.UnlinkedNamespaceDirective>[]);
-  }
-
-  @override
-  List<int> get lineStarts {
-    return _lineStarts ??=
-        const fb.Uint32ListReader().vTableGet(_bc, _bcOffset, 5, const <int>[]);
-  }
-
-  @override
-  String get partOfName {
-    return _partOfName ??=
-        const fb.StringReader().vTableGet(_bc, _bcOffset, 8, '');
-  }
-
-  @override
-  String get partOfUri {
-    return _partOfUri ??=
-        const fb.StringReader().vTableGet(_bc, _bcOffset, 7, '');
-  }
-
-  @override
-  List<String> get parts {
-    return _parts ??= const fb.ListReader<String>(fb.StringReader())
-        .vTableGet(_bc, _bcOffset, 4, const <String>[]);
-  }
-}
-
-abstract class _UnlinkedUnit2Mixin implements idl.UnlinkedUnit2 {
-  @override
-  Map<String, Object> toJson() {
-    Map<String, Object> _result = <String, Object>{};
-    var local_apiSignature = apiSignature;
-    if (local_apiSignature.isNotEmpty) {
-      _result["apiSignature"] = local_apiSignature;
-    }
-    var local_exports = exports;
-    if (local_exports.isNotEmpty) {
-      _result["exports"] =
-          local_exports.map((_value) => _value.toJson()).toList();
-    }
-    var local_hasLibraryDirective = hasLibraryDirective;
-    if (local_hasLibraryDirective != false) {
-      _result["hasLibraryDirective"] = local_hasLibraryDirective;
-    }
-    var local_hasPartOfDirective = hasPartOfDirective;
-    if (local_hasPartOfDirective != false) {
-      _result["hasPartOfDirective"] = local_hasPartOfDirective;
-    }
-    var local_imports = imports;
-    if (local_imports.isNotEmpty) {
-      _result["imports"] =
-          local_imports.map((_value) => _value.toJson()).toList();
-    }
-    var local_lineStarts = lineStarts;
-    if (local_lineStarts.isNotEmpty) {
-      _result["lineStarts"] = local_lineStarts;
-    }
-    var local_partOfName = partOfName;
-    if (local_partOfName != '') {
-      _result["partOfName"] = local_partOfName;
-    }
-    var local_partOfUri = partOfUri;
-    if (local_partOfUri != '') {
-      _result["partOfUri"] = local_partOfUri;
-    }
-    var local_parts = parts;
-    if (local_parts.isNotEmpty) {
-      _result["parts"] = local_parts;
-    }
-    return _result;
-  }
-
-  @override
-  Map<String, Object?> toMap() => {
-        "apiSignature": apiSignature,
-        "exports": exports,
-        "hasLibraryDirective": hasLibraryDirective,
-        "hasPartOfDirective": hasPartOfDirective,
-        "imports": imports,
-        "lineStarts": lineStarts,
-        "partOfName": partOfName,
-        "partOfUri": partOfUri,
-        "parts": parts,
-      };
-
-  @override
-  String toString() => convert.json.encode(toJson());
-}
diff --git a/pkg/analyzer/lib/src/summary/format.fbs b/pkg/analyzer/lib/src/summary/format.fbs
index 67ee567..44e5dc8 100644
--- a/pkg/analyzer/lib/src/summary/format.fbs
+++ b/pkg/analyzer/lib/src/summary/format.fbs
@@ -403,30 +403,6 @@
   signature:[uint] (id: 0);
 }
 
-/// Top-level declarations in a compilation unit.
-table CiderUnitTopLevelDeclarations {
-  extensionNames:[string] (id: 0);
-
-  functionNames:[string] (id: 1);
-
-  typeNames:[string] (id: 2);
-
-  variableNames:[string] (id: 3);
-}
-
-/// Information about a compilation unit, contains the content hash
-/// and unlinked summary.
-table CiderUnlinkedUnit {
-  /// The hash signature of the contents of the file.
-  contentDigest:[uint] (id: 0);
-
-  /// Top-level declarations of the unit.
-  topLevelDeclarations:CiderUnitTopLevelDeclarations (id: 1);
-
-  /// Unlinked summary of the compilation unit.
-  unlinkedUnit:UnlinkedUnit2 (id: 2);
-}
-
 table DiagnosticMessage {
   /// The absolute and normalized path of the file associated with this message.
   filePath:string (id: 0);
@@ -460,60 +436,6 @@
   fake:uint (id: 0);
 }
 
-/// Unlinked summary information about a namespace directive.
-table UnlinkedNamespaceDirective {
-  /// The configurations that control which library will actually be used.
-  configurations:[UnlinkedNamespaceDirectiveConfiguration] (id: 0);
-
-  /// The URI referenced by this directive, nad used by default when none
-  /// of the [configurations] matches.
-  uri:string (id: 1);
-}
-
-/// Unlinked summary information about a namespace directive configuration.
-table UnlinkedNamespaceDirectiveConfiguration {
-  /// The name of the declared variable used in the condition.
-  name:string (id: 0);
-
-  /// The URI to be used if the condition is true.
-  uri:string (id: 2);
-
-  /// The value to which the value of the declared variable will be compared,
-  /// or the empty string if the condition does not include an equality test.
-  value:string (id: 1);
-}
-
-/// Unlinked summary information about a compilation unit.
-table UnlinkedUnit2 {
-  /// The MD5 hash signature of the API portion of this unit. It depends on all
-  /// tokens that might affect APIs of declarations in the unit.
-  apiSignature:[uint] (id: 0);
-
-  /// URIs of `export` directives.
-  exports:[UnlinkedNamespaceDirective] (id: 1);
-
-  /// Is `true` if the unit contains a `library` directive.
-  hasLibraryDirective:bool (id: 6);
-
-  /// Is `true` if the unit contains a `part of` directive.
-  hasPartOfDirective:bool (id: 3);
-
-  /// URIs of `import` directives.
-  imports:[UnlinkedNamespaceDirective] (id: 2);
-
-  /// Offsets of the first character of each line in the source code.
-  lineStarts:[uint] (id: 5);
-
-  /// The library name of the `part of my.name;` directive.
-  partOfName:string (id: 8);
-
-  /// URI of the `part of 'uri';` directive.
-  partOfUri:string (id: 7);
-
-  /// URIs of `part` directives.
-  parts:[string] (id: 4);
-}
-
 root_type PackageBundle;
 
 file_identifier "PBdl";
diff --git a/pkg/analyzer/lib/src/summary/idl.dart b/pkg/analyzer/lib/src/summary/idl.dart
index cb5eb79..a17feaf 100644
--- a/pkg/analyzer/lib/src/summary/idl.dart
+++ b/pkg/analyzer/lib/src/summary/idl.dart
@@ -435,41 +435,6 @@
   List<int> get signature;
 }
 
-/// Top-level declarations in a compilation unit.
-abstract class CiderUnitTopLevelDeclarations extends base.SummaryClass {
-  @Id(0)
-  List<String> get extensionNames;
-
-  @Id(1)
-  List<String> get functionNames;
-
-  @Id(2)
-  List<String> get typeNames;
-
-  @Id(3)
-  List<String> get variableNames;
-}
-
-/// Information about a compilation unit, contains the content hash
-/// and unlinked summary.
-@TopLevel('CUUN')
-abstract class CiderUnlinkedUnit extends base.SummaryClass {
-  factory CiderUnlinkedUnit.fromBuffer(List<int> buffer) =>
-      generated.readCiderUnlinkedUnit(buffer);
-
-  /// The hash signature of the contents of the file.
-  @Id(0)
-  List<int> get contentDigest;
-
-  /// Top-level declarations of the unit.
-  @Id(1)
-  CiderUnitTopLevelDeclarations? get topLevelDeclarations;
-
-  /// Unlinked summary of the compilation unit.
-  @Id(2)
-  UnlinkedUnit2? get unlinkedUnit;
-}
-
 abstract class DiagnosticMessage extends base.SummaryClass {
   /// The absolute and normalized path of the file associated with this message.
   @Id(0)
@@ -606,77 +571,3 @@
   @Id(0)
   int get fake;
 }
-
-/// Unlinked summary information about a namespace directive.
-abstract class UnlinkedNamespaceDirective extends base.SummaryClass {
-  /// The configurations that control which library will actually be used.
-  @Id(0)
-  List<UnlinkedNamespaceDirectiveConfiguration> get configurations;
-
-  /// The URI referenced by this directive, nad used by default when none
-  /// of the [configurations] matches.
-  @Id(1)
-  String get uri;
-}
-
-/// Unlinked summary information about a namespace directive configuration.
-abstract class UnlinkedNamespaceDirectiveConfiguration
-    extends base.SummaryClass {
-  /// The name of the declared variable used in the condition.
-  @Id(0)
-  String get name;
-
-  /// The URI to be used if the condition is true.
-  @Id(2)
-  String get uri;
-
-  /// The value to which the value of the declared variable will be compared,
-  /// or the empty string if the condition does not include an equality test.
-  @Id(1)
-  String get value;
-}
-
-/// Unlinked summary information about a compilation unit.
-@TopLevel('UUN2')
-abstract class UnlinkedUnit2 extends base.SummaryClass {
-  factory UnlinkedUnit2.fromBuffer(List<int> buffer) =>
-      generated.readUnlinkedUnit2(buffer);
-
-  /// The MD5 hash signature of the API portion of this unit. It depends on all
-  /// tokens that might affect APIs of declarations in the unit.
-  @Id(0)
-  List<int> get apiSignature;
-
-  /// URIs of `export` directives.
-  @Id(1)
-  List<UnlinkedNamespaceDirective> get exports;
-
-  /// Is `true` if the unit contains a `library` directive.
-  @Id(6)
-  bool get hasLibraryDirective;
-
-  /// Is `true` if the unit contains a `part of` directive.
-  @Id(3)
-  bool get hasPartOfDirective;
-
-  /// URIs of `import` directives.
-  @Id(2)
-  List<UnlinkedNamespaceDirective> get imports;
-
-  /// Offsets of the first character of each line in the source code.
-  @informative
-  @Id(5)
-  List<int> get lineStarts;
-
-  /// The library name of the `part of my.name;` directive.
-  @Id(8)
-  String get partOfName;
-
-  /// URI of the `part of 'uri';` directive.
-  @Id(7)
-  String get partOfUri;
-
-  /// URIs of `part` directives.
-  @Id(4)
-  List<String> get parts;
-}
diff --git a/pkg/analyzer/lib/src/summary/package_bundle_reader.dart b/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
index 557f22c..6b789a8 100644
--- a/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
+++ b/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
@@ -162,7 +162,7 @@
     Uint8List bytes;
     if (resourceProvider != null) {
       var file = resourceProvider.getFile(path);
-      bytes = file.readAsBytesSync() as Uint8List;
+      bytes = file.readAsBytesSync();
     } else {
       io.File file = io.File(path);
       bytes = file.readAsBytesSync();
diff --git a/pkg/analyzer/pubspec.yaml b/pkg/analyzer/pubspec.yaml
index 7871444..8ce05d6 100644
--- a/pkg/analyzer/pubspec.yaml
+++ b/pkg/analyzer/pubspec.yaml
@@ -1,5 +1,5 @@
 name: analyzer
-version: 2.6.0-dev
+version: 2.6.0
 description: This package provides a library that performs static analysis of Dart code.
 homepage: https://github.com/dart-lang/sdk/tree/main/pkg/analyzer
 
@@ -7,7 +7,7 @@
   sdk: '>=2.14.0 <3.0.0'
 
 dependencies:
-  _fe_analyzer_shared: ^28.0.0
+  _fe_analyzer_shared: ^29.0.0
   cli_util: ^0.3.0
   collection: ^1.15.0
   convert: ^3.0.0
diff --git a/pkg/analyzer/test/file_system/file_system_test_support.dart b/pkg/analyzer/test/file_system/file_system_test_support.dart
index 6b5d0e2..722474a 100644
--- a/pkg/analyzer/test/file_system/file_system_test_support.dart
+++ b/pkg/analyzer/test/file_system/file_system_test_support.dart
@@ -2,6 +2,8 @@
 // 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.
 
+import 'dart:typed_data';
+
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:path/path.dart' as path;
@@ -203,8 +205,8 @@
   }
 
   test_lengthSync_existing() {
-    File file = getFile(exists: true);
-    List<int> bytes = <int>[1, 2, 3, 4, 5];
+    var file = getFile(exists: true);
+    var bytes = Uint8List.fromList([1, 2, 3, 4, 5]);
     file.writeAsBytesSync(bytes);
 
     expect(file.lengthSync, bytes.length);
@@ -393,8 +395,9 @@
   test_writeAsBytesSync_existing() {
     File file = getFile(exists: true);
 
-    file.writeAsBytesSync(<int>[99, 99]);
-    expect(file.readAsBytesSync(), <int>[99, 99]);
+    var bytes = Uint8List.fromList([99, 99]);
+    file.writeAsBytesSync(bytes);
+    expect(file.readAsBytesSync(), bytes);
   }
 
   test_writeAsBytesSync_notExisting();
diff --git a/pkg/analyzer/test/file_system/memory_file_system_test.dart b/pkg/analyzer/test/file_system/memory_file_system_test.dart
index 94b56ef..9eecb33 100644
--- a/pkg/analyzer/test/file_system/memory_file_system_test.dart
+++ b/pkg/analyzer/test/file_system/memory_file_system_test.dart
@@ -2,6 +2,8 @@
 // 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.
 
+import 'dart:typed_data';
+
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/generated/engine.dart' show TimestampedData;
@@ -265,9 +267,10 @@
   test_writeAsBytesSync_notExisting() {
     File file = getFile(exists: false);
 
-    file.writeAsBytesSync(<int>[99, 99]);
+    var bytes = Uint8List.fromList([99, 99]);
+    file.writeAsBytesSync(bytes);
     expect(file.exists, true);
-    expect(file.readAsBytesSync(), <int>[99, 99]);
+    expect(file.readAsBytesSync(), bytes);
   }
 
   @override
@@ -354,7 +357,7 @@
   }
 
   test_newFileWithBytes() {
-    List<int> bytes = <int>[1, 2, 3, 4, 5];
+    var bytes = Uint8List.fromList([1, 2, 3, 4, 5]);
 
     provider.newFileWithBytes(defaultFilePath, bytes);
     Resource file = provider.getResource(defaultFilePath);
diff --git a/pkg/analyzer/test/file_system/overlay_file_system_test.dart b/pkg/analyzer/test/file_system/overlay_file_system_test.dart
index 78d9cbf..fd9a6df 100644
--- a/pkg/analyzer/test/file_system/overlay_file_system_test.dart
+++ b/pkg/analyzer/test/file_system/overlay_file_system_test.dart
@@ -2,6 +2,8 @@
 // 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.
 
+import 'dart:typed_data';
+
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/file_system/overlay_file_system.dart';
@@ -360,14 +362,18 @@
 
   test_writeAsBytesSync_withoutOverlay() {
     File file = _file(exists: true);
-    file.writeAsBytesSync(<int>[99, 99]);
-    expect(file.readAsBytesSync(), <int>[99, 99]);
+    var bytes = Uint8List.fromList([99, 99]);
+    file.writeAsBytesSync(bytes);
+    expect(file.readAsBytesSync(), bytes);
   }
 
   test_writeAsBytesSync_withOverlay() {
     File file = _file(exists: true, withOverlay: true);
-    expect(() => file.writeAsBytesSync(<int>[99, 99]),
-        throwsA(_isFileSystemException));
+    var bytes = Uint8List.fromList([99, 99]);
+    expect(
+      () => file.writeAsBytesSync(bytes),
+      throwsA(_isFileSystemException),
+    );
   }
 
   test_writeAsStringSync_withoutOverlay() {
diff --git a/pkg/analyzer/test/file_system/physical_file_system_test.dart b/pkg/analyzer/test/file_system/physical_file_system_test.dart
index 3d33576..8794f1d 100644
--- a/pkg/analyzer/test/file_system/physical_file_system_test.dart
+++ b/pkg/analyzer/test/file_system/physical_file_system_test.dart
@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:io' as io;
+import 'dart:typed_data';
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/physical_file_system.dart';
@@ -131,8 +132,11 @@
   test_writeAsBytesSync_notExisting() {
     File file = getFile(exists: false);
 
-    expect(() => file.writeAsBytesSync(<int>[99, 99]),
-        throwsA(isFileSystemException));
+    var bytes = Uint8List.fromList([99, 99]);
+    expect(
+      () => file.writeAsBytesSync(bytes),
+      throwsA(isFileSystemException),
+    );
   }
 
   @override
diff --git a/pkg/analyzer/test/generated/constant_test.dart b/pkg/analyzer/test/generated/constant_test.dart
index 8bbf1fa..8de1d7f 100644
--- a/pkg/analyzer/test/generated/constant_test.dart
+++ b/pkg/analyzer/test/generated/constant_test.dart
@@ -48,50 +48,6 @@
     await _assertValueInt(74 ^ 42, "74 ^ 42");
   }
 
-  test_constructorInvocation_assert_false() async {
-    var result = await _getExpressionValue("const C(0)", context: '''
-class C {
-  const C(int x) : assert(x > 0);
-}
-''');
-    expect(result.isValid, isFalse);
-  }
-
-  test_constructorInvocation_assert_inherited() async {
-    var result = await _getExpressionValue(
-      "const Center(name: 'v')",
-      context: '''
-class Align {
-  final double? widthFactor;
-  const Align({String name, this.widthFactor})
-        assert(widthFactor == null || widthFactor >= 0.0);
-}
-class Center extends Align {
-  const Center({String name})
-    : super(name: name);
-}
-''',
-    );
-    expect(result.isValid, isTrue);
-    DartObject value = result.value!;
-    assertType(value.type, 'Center');
-    DartObject superclassFields =
-        value.getField(GenericState.SUPERCLASS_FIELD)!;
-    DartObject widthFactor = superclassFields.getField('widthFactor')!;
-    expect(widthFactor.isNull, isTrue);
-  }
-
-  test_constructorInvocation_assert_true() async {
-    var result = await _getExpressionValue("const C(3)", context: '''
-class C {
-  const C(int x) : assert(x > 0);
-}
-''');
-    expect(result.isValid, isTrue);
-    DartObject value = result.value!;
-    assertType(value.type, 'C');
-  }
-
   test_constructorInvocation_fieldInitializer() async {
     var result = await _getExpressionValue("const C(2)", context: '''
 class C {
diff --git a/pkg/analyzer/test/generated/non_error_resolver_test.dart b/pkg/analyzer/test/generated/non_error_resolver_test.dart
index a1cdefa..3770d7c 100644
--- a/pkg/analyzer/test/generated/non_error_resolver_test.dart
+++ b/pkg/analyzer/test/generated/non_error_resolver_test.dart
@@ -13,49 +13,12 @@
 
 main() {
   defineReflectiveSuite(() {
-    defineReflectiveTests(NonConstantValueInInitializer);
     defineReflectiveTests(NonErrorResolverTest);
     defineReflectiveTests(NonErrorResolverWithoutNullSafetyTest);
   });
 }
 
 @reflectiveTest
-class NonConstantValueInInitializer extends PubPackageResolutionTest {
-  test_intLiteralInDoubleContext_const_exact() async {
-    await assertNoErrorsInCode(r'''
-// @dart = 2.9
-const double x = 0;
-class C {
-  const C(double y) : assert(y is double), assert(x is double);
-}
-@C(0)
-@C(-0)
-@C(0x0)
-@C(-0x0)
-void main() {
-  const C(0);
-  const C(-0);
-  const C(0x0);
-  const C(-0x0);
-}
-''');
-  }
-
-  test_isCheckInConstAssert() async {
-    await assertNoErrorsInCode(r'''
-// @dart = 2.9
-class C {
-  const C() : assert(1 is int);
-}
-
-void main() {
-  const C();
-}
-''');
-  }
-}
-
-@reflectiveTest
 class NonErrorResolverTest extends PubPackageResolutionTest
     with NonErrorResolverTestCases {
   test_await_flattened() async {
@@ -1790,26 +1753,6 @@
 ''');
   }
 
-  test_intLiteralInDoubleContext_const() async {
-    await assertNoErrorsInCode(r'''
-class C {
-  const C(double x)
-    : assert((x + 3) / 2 == 1.5)
-    , assert(x == 0.0);
-}
-@C(0)
-@C(-0)
-@C(0x0)
-@C(-0x0)
-void main() {
-  const C(0);
-  const C(-0);
-  const C(0x0);
-  const C(-0x0);
-}
-''');
-  }
-
   test_invalidAnnotation_constantVariable_field() async {
     await assertNoErrorsInCode(r'''
 @A.C
diff --git a/pkg/analyzer/test/resource_utils.dart b/pkg/analyzer/test/resource_utils.dart
index 680004d..3337265 100644
--- a/pkg/analyzer/test/resource_utils.dart
+++ b/pkg/analyzer/test/resource_utils.dart
@@ -2,6 +2,8 @@
 // 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.
 
+import 'dart:typed_data';
+
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/generated/source.dart';
@@ -62,7 +64,7 @@
   File newFile(String posixPath, String content) =>
       _provider.newFile(posixToOSPath(posixPath), content);
 
-  File newFileWithBytes(String posixPath, List<int> bytes) =>
+  File newFileWithBytes(String posixPath, Uint8List bytes) =>
       _provider.newFileWithBytes(posixToOSPath(posixPath), bytes);
 
   Folder newFolder(String posixPath) =>
diff --git a/pkg/analyzer/test/src/dart/constant/evaluation_test.dart b/pkg/analyzer/test/src/dart/constant/evaluation_test.dart
index f2dd07e..33de914 100644
--- a/pkg/analyzer/test/src/dart/constant/evaluation_test.dart
+++ b/pkg/analyzer/test/src/dart/constant/evaluation_test.dart
@@ -20,6 +20,8 @@
   defineReflectiveSuite(() {
     defineReflectiveTests(ConstantVisitorTest);
     defineReflectiveTests(ConstantVisitorWithoutNullSafetyTest);
+    defineReflectiveTests(InstanceCreationEvaluatorTest);
+    defineReflectiveTests(InstanceCreationEvaluatorWithoutNullSafetyTest);
   });
 }
 
@@ -318,152 +320,6 @@
     );
   }
 
-  test_instanceCreationExpression_redirecting_typeParameter() async {
-    await resolveTestCode('''
-class A<T> {
-  final Object f;
-  const A(): this.named(T);
-  const A.named(Object t): f = t;
-}
-const a = const A<int>();
-''');
-    var result = _evaluateConstant('a');
-    expect(result, isNotNull);
-  }
-
-  test_instanceCreationExpression_typeParameter() async {
-    await resolveTestCode('''
-class A<T> {
-  final Object f;
-  const A(): f = T;
-}
-const a = const A<int>();
-''');
-    var result = _evaluateConstant('a');
-    var aElement = findElement.class_('A');
-    var expectedType = aElement.instantiate(
-        typeArguments: [typeProvider.intType],
-        nullabilitySuffix: NullabilitySuffix.none);
-    expect(result.type, expectedType);
-  }
-
-  test_instanceCreationExpression_typeParameter_implicitTypeArgs() async {
-    await resolveTestCode('''
-class A<T> {
-  final Object f;
-  const A(): f = T;
-}
-const a = const A();
-''');
-    var result = _evaluateConstant('a');
-    var aElement = findElement.class_('A');
-    var expectedType = aElement.instantiate(
-        typeArguments: [typeProvider.dynamicType],
-        nullabilitySuffix: NullabilitySuffix.none);
-    expect(result.type, expectedType);
-  }
-
-  test_instanceCreationExpression_typeParameter_super() async {
-    await resolveTestCode('''
-class A<T> {
-  final Object f;
-  const A(Object t): f = t;
-}
-class B<T> extends A<T> {
-  const B(): super(T);
-}
-const a = const B<int>();
-''');
-    var result = _evaluateConstant('a');
-    var bElement = findElement.class_('B');
-    var expectedType = bElement.instantiate(
-        typeArguments: [typeProvider.intType],
-        nullabilitySuffix: NullabilitySuffix.none);
-    expect(result.type, expectedType);
-  }
-
-  test_instanceCreationExpression_typeParameter_superNonGeneric() async {
-    await resolveTestCode('''
-class A {
-  final Object f;
-  const A(Object t): f = t;
-}
-class B<T> extends A {
-  const B(): super(T);
-}
-const a = const B<int>();
-''');
-    var result = _evaluateConstant('a');
-    expect(result, isNotNull);
-  }
-
-  test_instanceCreationExpression_typeParameter_typeAlias() async {
-    await resolveTestCode('''
-class A<T, U> {
-  final Object f, g;
-  const A(): f = T, g = U;
-}
-typedef B<S> = A<int, S>;
-const a = const B<String>();
-''');
-    var result = _evaluateConstant('a');
-    var aElement = findElement.class_('A');
-    var expectedType = aElement.instantiate(
-        typeArguments: [typeProvider.intType, typeProvider.stringType],
-        nullabilitySuffix: NullabilitySuffix.none);
-    expect(result.type, expectedType);
-  }
-
-  test_instanceCreationExpression_typeParameter_withoutConstructorTearoffs() async {
-    await resolveTestCode('''
-// @dart=2.12
-class A<T> {
-  final Object f;
-  const A(): f = T;
-}
-const a = const A<int>();
-''');
-    var result = _evaluateConstant('a', errorCodes: [
-      CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION,
-      CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION,
-    ]);
-    var aElement = findElement.class_('A');
-    var expectedType = aElement.instantiate(
-        typeArguments: [typeProvider.intType],
-        nullabilitySuffix: NullabilitySuffix.none);
-    expect(result.type, expectedType);
-  }
-
-  test_typeParameter() async {
-    await resolveTestCode('''
-class A<X> {
-  const A();
-  void m() {
-    const x = X;
-  }
-}
-''');
-    var result = _evaluateConstantLocal('x', errorCodes: [
-      CompileTimeErrorCode.INVALID_CONSTANT,
-    ]);
-    expect(result, isNull);
-  }
-
-  test_visitAsExpression_potentialConstType() async {
-    await assertNoErrorsInCode('''
-const num three = 3;
-
-class C<T extends num> {
-  final T w;
-  const C() : w = three as T;
-}
-
-void main() {
-  const C<int>().w;
-}
-''');
-  }
-
   test_visitBinaryExpression_gtGtGt_negative_fewerBits() async {
     await resolveTestCode('''
 const c = 0xFFFFFFFF >>> 8;
@@ -1027,6 +883,21 @@
     expect(result.toSetValue()!.map((e) => e.toIntValue()), [1, 2, 3, 4]);
   }
 
+  test_typeParameter() async {
+    await resolveTestCode('''
+class A<X> {
+  const A();
+  void m() {
+    const x = X;
+  }
+}
+''');
+    var result = _evaluateConstantLocal('x', errorCodes: [
+      CompileTimeErrorCode.INVALID_CONSTANT,
+    ]);
+    expect(result, isNull);
+  }
+
   test_visitAsExpression_instanceOfSameClass() async {
     await resolveTestCode('''
 const a = const A();
@@ -1522,91 +1393,6 @@
         errorCodes: [CompileTimeErrorCode.INVALID_CONSTANT]);
   }
 
-  test_visitInstanceCreationExpression_bool_fromEnvironment() async {
-    await resolveTestCode('''
-const a = bool.fromEnvironment('a');
-const b = bool.fromEnvironment('b', defaultValue: true);
-''');
-    expect(
-      _evaluateConstant('a'),
-      _boolValue(false),
-    );
-    expect(
-      _evaluateConstant('a', declaredVariables: {'a': 'true'}),
-      _boolValue(true),
-    );
-
-    expect(
-      _evaluateConstant(
-        'b',
-        declaredVariables: {'b': 'bbb'},
-        lexicalEnvironment: {'defaultValue': _boolValue(true)},
-      ),
-      _boolValue(true),
-    );
-  }
-
-  test_visitInstanceCreationExpression_bool_hasEnvironment() async {
-    await resolveTestCode('''
-const a = bool.hasEnvironment('a');
-''');
-    expect(
-      _evaluateConstant('a'),
-      _boolValue(false),
-    );
-
-    expect(
-      _evaluateConstant('a', declaredVariables: {'a': '42'}),
-      _boolValue(true),
-    );
-  }
-
-  test_visitInstanceCreationExpression_int_fromEnvironment() async {
-    await resolveTestCode('''
-const a = int.fromEnvironment('a');
-const b = int.fromEnvironment('b', defaultValue: 42);
-''');
-    expect(
-      _evaluateConstant('a'),
-      _intValue(0),
-    );
-    expect(
-      _evaluateConstant('a', declaredVariables: {'a': '5'}),
-      _intValue(5),
-    );
-
-    expect(
-      _evaluateConstant(
-        'b',
-        declaredVariables: {'b': 'bbb'},
-        lexicalEnvironment: {'defaultValue': _intValue(42)},
-      ),
-      _intValue(42),
-    );
-  }
-
-  test_visitInstanceCreationExpression_string_fromEnvironment() async {
-    await resolveTestCode('''
-const a = String.fromEnvironment('a');
-''');
-    expect(
-      _evaluateConstant('a'),
-      DartObjectImpl(
-        typeSystem,
-        typeProvider.stringType,
-        StringState(''),
-      ),
-    );
-    expect(
-      _evaluateConstant('a', declaredVariables: {'a': 'test'}),
-      DartObjectImpl(
-        typeSystem,
-        typeProvider.stringType,
-        StringState('test'),
-      ),
-    );
-  }
-
   test_visitIntegerLiteral() async {
     await resolveTestCode('''
 const double d = 3;
@@ -1930,7 +1716,9 @@
     expect(result.type, typeProvider.intType);
     expect(result.toIntValue(), 3);
   }
+}
 
+class ConstantVisitorTestSupport extends PubPackageResolutionTest {
   void _assertBoolValue(DartObjectImpl result, bool value) {
     expect(result.type, typeProvider.boolType);
     expect(result.toBoolValue(), value);
@@ -1941,6 +1729,24 @@
     expect(result.toIntValue(), value);
   }
 
+  void _assertTypeArguments(DartObject value, List<String>? typeArgumentNames) {
+    var typeArguments = (value as DartObjectImpl).typeArguments;
+    if (typeArguments == null) {
+      expect(typeArguments, typeArgumentNames);
+      return;
+    }
+    expect(
+      typeArguments.map((arg) => arg.getDisplayString(withNullability: true)),
+      equals(typeArgumentNames),
+    );
+  }
+
+  /// Asserts that evaluation of [name] results in no errors, and a non-null
+  /// [DartObject].
+  void _assertValidConstant(String name) {
+    _evaluateConstant(name);
+  }
+
   DartObjectImpl _boolValue(bool value) {
     if (identical(value, false)) {
       return DartObjectImpl(
@@ -1958,28 +1764,6 @@
     fail("Invalid boolean value used in test");
   }
 
-  DartObjectImpl _intValue(int value) {
-    return DartObjectImpl(
-      typeSystem,
-      typeProvider.intType,
-      IntState(value),
-    );
-  }
-}
-
-class ConstantVisitorTestSupport extends PubPackageResolutionTest {
-  void _assertTypeArguments(DartObject value, List<String>? typeArgumentNames) {
-    var typeArguments = (value as DartObjectImpl).typeArguments;
-    if (typeArguments == null) {
-      expect(typeArguments, typeArgumentNames);
-      return;
-    }
-    expect(
-      typeArguments.map((arg) => arg.getDisplayString(withNullability: true)),
-      equals(typeArgumentNames),
-    );
-  }
-
   DartObjectImpl _evaluateConstant(
     String name, {
     List<ErrorCode>? errorCodes,
@@ -2058,6 +1842,14 @@
     }
     return result;
   }
+
+  DartObjectImpl _intValue(int value) {
+    return DartObjectImpl(
+      typeSystem,
+      typeProvider.intType,
+      IntState(value),
+    );
+  }
 }
 
 @reflectiveTest
@@ -2073,3 +1865,339 @@
     expect(result.type, typeProvider.nullType);
   }
 }
+
+@reflectiveTest
+class InstanceCreationEvaluatorTest extends ConstantVisitorTestSupport
+    with InstanceCreationEvaluatorTestCases {
+  test_fieldInitializer_typeParameter() async {
+    await resolveTestCode('''
+class A<T> {
+  final Object f;
+  const A(): f = T;
+}
+const a = const A<int>();
+''');
+    var result = _evaluateConstant('a');
+    var aElement = findElement.class_('A');
+    var expectedType = aElement.instantiate(
+        typeArguments: [typeProvider.intType],
+        nullabilitySuffix: NullabilitySuffix.none);
+    expect(result.type, expectedType);
+  }
+
+  test_fieldInitializer_typeParameter_implicitTypeArgs() async {
+    await resolveTestCode('''
+class A<T> {
+  final Object f;
+  const A(): f = T;
+}
+const a = const A();
+''');
+    var result = _evaluateConstant('a');
+    var aElement = findElement.class_('A');
+    var expectedType = aElement.instantiate(
+        typeArguments: [typeProvider.dynamicType],
+        nullabilitySuffix: NullabilitySuffix.none);
+    expect(result.type, expectedType);
+  }
+
+  test_fieldInitializer_typeParameter_typeAlias() async {
+    await resolveTestCode('''
+class A<T, U> {
+  final Object f, g;
+  const A(): f = T, g = U;
+}
+typedef B<S> = A<int, S>;
+const a = const B<String>();
+''');
+    var result = _evaluateConstant('a');
+    var aElement = findElement.class_('A');
+    var expectedType = aElement.instantiate(
+        typeArguments: [typeProvider.intType, typeProvider.stringType],
+        nullabilitySuffix: NullabilitySuffix.none);
+    expect(result.type, expectedType);
+  }
+
+  test_fieldInitializer_typeParameter_withoutConstructorTearoffs() async {
+    await resolveTestCode('''
+// @dart=2.12
+class A<T> {
+  final Object f;
+  const A(): f = T;
+}
+const a = const A<int>();
+''');
+    var result = _evaluateConstant('a', errorCodes: [
+      CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION,
+      CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION,
+    ]);
+    var aElement = findElement.class_('A');
+    var expectedType = aElement.instantiate(
+        typeArguments: [typeProvider.intType],
+        nullabilitySuffix: NullabilitySuffix.none);
+    expect(result.type, expectedType);
+  }
+
+  test_fieldInitializer_visitAsExpression_potentialConstType() async {
+    await assertNoErrorsInCode('''
+const num three = 3;
+
+class C<T extends num> {
+  final T w;
+  const C() : w = three as T;
+}
+
+void main() {
+  const C<int>().w;
+}
+''');
+  }
+
+  test_redirectingConstructor_typeParameter() async {
+    await resolveTestCode('''
+class A<T> {
+  final Object f;
+  const A(): this.named(T);
+  const A.named(Object t): f = t;
+}
+const a = const A<int>();
+''');
+    var result = _evaluateConstant('a');
+    expect(result, isNotNull);
+  }
+
+  test_superInitializer_typeParameter() async {
+    await resolveTestCode('''
+class A<T> {
+  final Object f;
+  const A(Object t): f = t;
+}
+class B<T> extends A<T> {
+  const B(): super(T);
+}
+const a = const B<int>();
+''');
+    var result = _evaluateConstant('a');
+    var bElement = findElement.class_('B');
+    var expectedType = bElement.instantiate(
+        typeArguments: [typeProvider.intType],
+        nullabilitySuffix: NullabilitySuffix.none);
+    expect(result.type, expectedType);
+  }
+
+  test_superInitializer_typeParameter_superNonGeneric() async {
+    await resolveTestCode('''
+class A {
+  final Object f;
+  const A(Object t): f = t;
+}
+class B<T> extends A {
+  const B(): super(T);
+}
+const a = const B<int>();
+''');
+    var result = _evaluateConstant('a');
+    expect(result, isNotNull);
+  }
+}
+
+@reflectiveTest
+mixin InstanceCreationEvaluatorTestCases on ConstantVisitorTestSupport {
+  test_assertInitializer_intInDoubleContext_assertIsDouble_true() async {
+    await resolveTestCode('''
+class A {
+  const A(double x): assert(x is double);
+}
+const a = const A(0);
+''');
+    _assertValidConstant('a');
+  }
+
+  test_assertInitializer_intInDoubleContext_false() async {
+    await resolveTestCode('''
+class A {
+  const A(double x): assert((x + 3) / 2 == 1.5);
+}
+const a = const A(1);
+''');
+    _evaluateConstantOrNull(
+      'a',
+      errorCodes: [CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION],
+    );
+  }
+
+  test_assertInitializer_intInDoubleContext_true() async {
+    await resolveTestCode('''
+class A {
+  const A(double x): assert((x + 3) / 2 == 1.5);
+}
+const a = const A(0);
+''');
+    _assertValidConstant('a');
+  }
+
+  test_assertInitializer_simple_false() async {
+    await resolveTestCode('''
+class A {
+  const A(): assert(1 is String);
+}
+const a = const A();
+''');
+    _evaluateConstantOrNull(
+      'a',
+      errorCodes: [CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION],
+    );
+  }
+
+  test_assertInitializer_simple_true() async {
+    await resolveTestCode('''
+class A {
+  const A(): assert(1 is int);
+}
+const a = const A();
+''');
+    _assertValidConstant('a');
+  }
+
+  test_assertInitializer_simpleInSuperInitializer_false() async {
+    await resolveTestCode('''
+class A {
+  const A(): assert(1 is String);
+}
+class B extends A {
+  const B() : super();
+}
+const b = const B();
+''');
+    _evaluateConstantOrNull(
+      'b',
+      errorCodes: [CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION],
+    );
+  }
+
+  test_assertInitializer_simpleInSuperInitializer_true() async {
+    await resolveTestCode('''
+class A {
+  const A(): assert(1 is int);
+}
+class B extends A {
+  const B() : super();
+}
+const b = const B();
+''');
+    _assertValidConstant('b');
+  }
+
+  test_assertInitializer_usingArgument_false() async {
+    await resolveTestCode('''
+class A {
+  const A(int x): assert(x > 0);
+}
+const a = const A(0);
+''');
+    _evaluateConstantOrNull(
+      'a',
+      errorCodes: [CompileTimeErrorCode.CONST_EVAL_THROWS_EXCEPTION],
+    );
+  }
+
+  test_assertInitializer_usingArgument_true() async {
+    await resolveTestCode('''
+class A {
+  const A(int x): assert(x > 0);
+}
+const a = const A(1);
+''');
+    _assertValidConstant('a');
+  }
+
+  test_bool_fromEnvironment() async {
+    await resolveTestCode('''
+const a = bool.fromEnvironment('a');
+const b = bool.fromEnvironment('b', defaultValue: true);
+''');
+    expect(
+      _evaluateConstant('a'),
+      _boolValue(false),
+    );
+    expect(
+      _evaluateConstant('a', declaredVariables: {'a': 'true'}),
+      _boolValue(true),
+    );
+
+    expect(
+      _evaluateConstant(
+        'b',
+        declaredVariables: {'b': 'bbb'},
+        lexicalEnvironment: {'defaultValue': _boolValue(true)},
+      ),
+      _boolValue(true),
+    );
+  }
+
+  test_bool_hasEnvironment() async {
+    await resolveTestCode('''
+const a = bool.hasEnvironment('a');
+''');
+    expect(
+      _evaluateConstant('a'),
+      _boolValue(false),
+    );
+
+    expect(
+      _evaluateConstant('a', declaredVariables: {'a': '42'}),
+      _boolValue(true),
+    );
+  }
+
+  test_int_fromEnvironment() async {
+    await resolveTestCode('''
+const a = int.fromEnvironment('a');
+const b = int.fromEnvironment('b', defaultValue: 42);
+''');
+    expect(
+      _evaluateConstant('a'),
+      _intValue(0),
+    );
+    expect(
+      _evaluateConstant('a', declaredVariables: {'a': '5'}),
+      _intValue(5),
+    );
+
+    expect(
+      _evaluateConstant(
+        'b',
+        declaredVariables: {'b': 'bbb'},
+        lexicalEnvironment: {'defaultValue': _intValue(42)},
+      ),
+      _intValue(42),
+    );
+  }
+
+  test_string_fromEnvironment() async {
+    await resolveTestCode('''
+const a = String.fromEnvironment('a');
+''');
+    expect(
+      _evaluateConstant('a'),
+      DartObjectImpl(
+        typeSystem,
+        typeProvider.stringType,
+        StringState(''),
+      ),
+    );
+    expect(
+      _evaluateConstant('a', declaredVariables: {'a': 'test'}),
+      DartObjectImpl(
+        typeSystem,
+        typeProvider.stringType,
+        StringState('test'),
+      ),
+    );
+  }
+}
+
+@reflectiveTest
+class InstanceCreationEvaluatorWithoutNullSafetyTest
+    extends ConstantVisitorTestSupport
+    with InstanceCreationEvaluatorTestCases, WithoutNullSafetyMixin {}
diff --git a/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart b/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart
index 6e07a14..52f968e 100644
--- a/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart
+++ b/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart
@@ -4,6 +4,7 @@
 
 import 'package:analyzer/src/dart/error/syntactic_errors.dart';
 import 'package:analyzer/src/dart/micro/cider_byte_store.dart';
+import 'package:analyzer/src/dart/micro/library_graph.dart';
 import 'package:analyzer/src/dart/micro/resolve_file.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/lint/registry.dart';
@@ -743,6 +744,32 @@
     expect(fileResolver.testView!.resolvedLibraries, <Object>[]);
   }
 
+  test_getFilesWithTopLevelDeclarations_cached() async {
+    await assertNoErrorsInCode(r'''
+int a = 0;
+var b = 1 + 2;
+''');
+
+    void assertHasOneVariable() {
+      var files = fileResolver.getFilesWithTopLevelDeclarations('a');
+      expect(files, hasLength(1));
+      var file = files.single;
+      expect(file.file.path, result.path);
+      expect(file.kind, FileTopLevelDeclarationKind.variable);
+    }
+
+    // Ask to check that it works when parsed.
+    assertHasOneVariable();
+
+    // Create a new resolved, but reuse the cache.
+    createFileResolver();
+
+    await resolveTestFile();
+
+    // Ask again, when unlinked information is read from the cache.
+    assertHasOneVariable();
+  }
+
   test_getLibraryByUri() {
     newFile('/workspace/dart/my/lib/a.dart', content: r'''
 class A {}
diff --git a/pkg/compiler/testing.json b/pkg/compiler/testing.json
index 7885980..923911a 100644
--- a/pkg/compiler/testing.json
+++ b/pkg/compiler/testing.json
@@ -3,7 +3,7 @@
 "":"for details. All rights reserved. Use of this source code is governed by a",
 "":"BSD-style license that can be found in the LICENSE.md file.",
 
-  "packages": "../../.packages",
+  "packages": "../../.dart_tool/package_config.json",
 
   "analyze": {
     "options": "analysis_options.yaml",
diff --git a/pkg/dev_compiler/test/sourcemap/testing.json b/pkg/dev_compiler/test/sourcemap/testing.json
index 03c2722..5f6e6a8 100644
--- a/pkg/dev_compiler/test/sourcemap/testing.json
+++ b/pkg/dev_compiler/test/sourcemap/testing.json
@@ -2,7 +2,7 @@
 "":"Copyright (c) 2017, 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.md file.",
-  "packages": "../../../../.packages",
+  "packages": "../../../../.dart_tool/package_config.json",
   "suites": [
     {
       "name": "sourcemaps_ddk",
diff --git a/pkg/front_end/test/fasta/parser/testing.json b/pkg/front_end/test/fasta/parser/testing.json
index b3ae4c8..8265d1e 100644
--- a/pkg/front_end/test/fasta/parser/testing.json
+++ b/pkg/front_end/test/fasta/parser/testing.json
@@ -2,7 +2,7 @@
 "":"Copyright (c) 2016, 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.md file.",
-  "packages": "../../../../../.packages",
+  "packages": "../../../../../.dart_tool/package_config.json",
   "suites": [
     {
       "name": "parser",
diff --git a/pkg/front_end/test/fasta/scanner/testing.json b/pkg/front_end/test/fasta/scanner/testing.json
index be732cb..711f0cf 100644
--- a/pkg/front_end/test/fasta/scanner/testing.json
+++ b/pkg/front_end/test/fasta/scanner/testing.json
@@ -2,7 +2,7 @@
 "":"Copyright (c) 2016, 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.md file.",
-  "packages": "../../../../../.packages",
+  "packages": "../../../../../.dart_tool/package_config.json",
   "suites": [
     {
       "name": "scanner",
diff --git a/pkg/front_end/test/lint_suite.dart b/pkg/front_end/test/lint_suite.dart
index af61e9a..130a452 100644
--- a/pkg/front_end/test/lint_suite.dart
+++ b/pkg/front_end/test/lint_suite.dart
@@ -169,7 +169,8 @@
       description.cache.firstToken = scanner.tokenize();
       description.cache.lineStarts = scanner.lineStarts;
 
-      Uri dotPackages = description.uri.resolve(".packages");
+      Uri dotPackages =
+          description.uri.resolve(".dart_tool/package_config.json");
       while (true) {
         if (new File.fromUri(dotPackages).existsSync()) {
           break;
@@ -178,7 +179,8 @@
         if (dotPackages.pathSegments.length < Uri.base.pathSegments.length) {
           break;
         }
-        dotPackages = dotPackages.resolve("../.packages");
+        dotPackages =
+            dotPackages.resolve("../../.dart_tool/package_config.json");
       }
 
       File dotPackagesFile = new File.fromUri(dotPackages);
diff --git a/pkg/front_end/testing.json b/pkg/front_end/testing.json
index 8c5b79e..63cd5db 100644
--- a/pkg/front_end/testing.json
+++ b/pkg/front_end/testing.json
@@ -2,7 +2,7 @@
   "": "Copyright (c) 2016, 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.md file.",
-  "packages": "../../.packages",
+  "packages": "../../.dart_tool/package_config.json",
   "suites": [
     {
       "name": "messages",
diff --git a/pkg/front_end/testing_with_lints.json b/pkg/front_end/testing_with_lints.json
index 6cdef88..4570a39 100644
--- a/pkg/front_end/testing_with_lints.json
+++ b/pkg/front_end/testing_with_lints.json
@@ -3,7 +3,7 @@
 "ignored_2":"for details. All rights reserved. Use of this source code is governed by a",
 "ignored_3":"BSD-style license that can be found in the LICENSE.md file.",
 
-  "packages": "../../.packages",
+  "packages": "../../.dart_tool/package_config.json",
   "analyze": {
     "options": "analysis_options.yaml",
     "uris": [
diff --git a/pkg/testing/testing.json b/pkg/testing/testing.json
index 722834d..78faafc 100644
--- a/pkg/testing/testing.json
+++ b/pkg/testing/testing.json
@@ -3,7 +3,7 @@
 "":"for details. All rights reserved. Use of this source code is governed by a",
 "":"BSD-style license that can be found in the LICENSE.md file.",
 
-  "packages": "../../.packages",
+  "packages": "../../.dart_tool/package_config.json",
 
   "suites": [
     {
diff --git a/runtime/observatory/BUILD.gn b/runtime/observatory/BUILD.gn
index 80b6d6e..86647e8 100644
--- a/runtime/observatory/BUILD.gn
+++ b/runtime/observatory/BUILD.gn
@@ -13,7 +13,7 @@
 
   # dart2js produces a .deps file, but it is not in a format that is understood
   # by ninja, so we explicitly list all the sources here.
-  inputs = [ "../../.packages" ] + observatory_sources
+  inputs = [ "../../.dart_tool/package_config.json" ] + observatory_sources
 
   output = "$target_gen_dir/observatory/web/main.dart.js"
   outputs = [ output ]
@@ -24,7 +24,7 @@
   args = [
     "-o",
     rebase_path(output),
-    "--packages=" + rebase_path("../../.packages"),
+    "--packages=" + rebase_path("../../.dart_tool/package_config.json"),
     "--no-sound-null-safety",
   ]
   if (is_debug) {
diff --git a/runtime/observatory/lib/object_graph.dart b/runtime/observatory/lib/object_graph.dart
index 85f64df..18e0fae 100644
--- a/runtime/observatory/lib/object_graph.dart
+++ b/runtime/observatory/lib/object_graph.dart
@@ -590,6 +590,22 @@
       this._graph, this._cid, this.name, this.libName, this.libUri);
 }
 
+class _SyntheticSnapshotClass implements SnapshotClass {
+  final _SyntheticSnapshotObject _node;
+  _SyntheticSnapshotClass(this._node);
+
+  String get name => _node.description;
+  String get qualifiedName => _node.description;
+
+  int get shallowSize => _node.shallowSize;
+  int get externalSize => _node.externalSize;
+  int get internalSize => _node.internalSize;
+  int get ownedSize => 0;
+
+  int get instanceCount => 1;
+  Iterable<SnapshotObject> get instances => <SnapshotObject>[_node];
+}
+
 /// The analyzed graph from a heap snapshot.
 abstract class SnapshotGraph {
   String get description;
@@ -674,19 +690,19 @@
     var mlive = mergedRoot;
 
     capacity._description = "Capacity + External";
-    capacity._klass = live.klass;
-    capacity._internalSize = _capacity!;
-    capacity._externalSize = _totalExternalSize!;
-    capacity._retainedSize = capacity._internalSize + capacity._externalSize;
+    capacity._klass = new _SyntheticSnapshotClass(capacity);
+    capacity._internalSize = 0; // No shallow size.
+    capacity._externalSize = 0; // No shallow size.
+    capacity._retainedSize = _capacity! + _totalExternalSize!;
     capacity._successors = <SnapshotObject>[live, uncollected, fragmentation];
     capacity._predecessors = <SnapshotObject>[];
     capacity._children = <SnapshotObject>[live, uncollected, fragmentation];
 
     mcapacity._description = "Capacity + External";
-    mcapacity._klass = mlive.klass;
-    mcapacity._internalSize = _capacity!;
-    mcapacity._externalSize = _totalExternalSize!;
-    mcapacity._retainedSize = mcapacity._internalSize + mcapacity._externalSize;
+    mcapacity._klass = capacity._klass;
+    mcapacity._internalSize = 0; // No shallow size.
+    mcapacity._externalSize = 0; // No shallow size.
+    mcapacity._retainedSize = _capacity! + _totalExternalSize!;
     mcapacity._children = <SnapshotMergedDominator>[
       mlive,
       muncollected,
@@ -695,7 +711,7 @@
     mcapacity._objects = <SnapshotObject>[capacity];
 
     uncollected._description = "Uncollected Garbage";
-    uncollected._klass = live.klass;
+    uncollected._klass = new _SyntheticSnapshotClass(uncollected);
     uncollected._internalSize = _totalInternalSize! - _liveInternalSize!;
     uncollected._externalSize = _totalExternalSize! - _liveExternalSize!;
     uncollected._retainedSize =
@@ -706,7 +722,7 @@
     uncollected._children = <SnapshotObject>[];
 
     muncollected._description = "Uncollected Garbage";
-    muncollected._klass = mlive.klass;
+    muncollected._klass = uncollected._klass;
     muncollected._internalSize = _totalInternalSize! - _liveInternalSize!;
     muncollected._externalSize = _totalExternalSize! - _liveExternalSize!;
     muncollected._retainedSize =
@@ -716,7 +732,7 @@
     muncollected._objects = <SnapshotObject>[uncollected];
 
     fragmentation._description = "Free";
-    fragmentation._klass = live.klass;
+    fragmentation._klass = new _SyntheticSnapshotClass(fragmentation);
     fragmentation._internalSize = _capacity! - _totalInternalSize!;
     fragmentation._externalSize = 0;
     fragmentation._retainedSize = fragmentation._internalSize;
@@ -726,7 +742,7 @@
     fragmentation._children = <SnapshotObject>[];
 
     mfragmentation._description = "Free";
-    mfragmentation._klass = mlive.klass;
+    mfragmentation._klass = fragmentation._klass;
     mfragmentation._internalSize = _capacity! - _totalInternalSize!;
     mfragmentation._externalSize = 0;
     mfragmentation._retainedSize = mfragmentation._internalSize;
diff --git a/runtime/observatory/lib/src/elements/heap_snapshot.dart b/runtime/observatory/lib/src/elements/heap_snapshot.dart
index c8a5829..7deb8c7 100644
--- a/runtime/observatory/lib/src/elements/heap_snapshot.dart
+++ b/runtime/observatory/lib/src/elements/heap_snapshot.dart
@@ -792,7 +792,7 @@
         break;
       case HeapSnapshotTreeMode.mergedDominatorTreeDiff:
         var root = MergedDominatorDiff.from(
-            _snapshotA!.mergedRoot, _snapshotB!.mergedRoot);
+            _snapshotA!.extendedMergedRoot, _snapshotB!.extendedMergedRoot);
         _tree = new VirtualTreeElement(_createMergedDominatorDiff,
             _updateMergedDominatorDiff, _getChildrenMergedDominatorDiff,
             items: _getChildrenMergedDominatorDiff(root), queue: _r.queue);
@@ -816,7 +816,7 @@
       case HeapSnapshotTreeMode.mergedDominatorTreeMapDiff:
         if (mergedDiffSelection == null) {
           mergedDiffSelection = MergedDominatorDiff.from(
-              _snapshotA!.mergedRoot, _snapshotB!.mergedRoot);
+              _snapshotA!.extendedMergedRoot, _snapshotB!.extendedMergedRoot);
         }
         _createTreeMap(
             report, new MergedDominatorDiffTreeMap(this), mergedDiffSelection);
diff --git a/runtime/observatory_2/BUILD.gn b/runtime/observatory_2/BUILD.gn
index 412e378..b21c2f0 100644
--- a/runtime/observatory_2/BUILD.gn
+++ b/runtime/observatory_2/BUILD.gn
@@ -13,7 +13,7 @@
 
   # dart2js produces a .deps file, but it is not in a format that is understood
   # by ninja, so we explicitly list all the sources here.
-  inputs = [ "../../.packages" ] + observatory_sources
+  inputs = [ "../../.dart_tool/package_config.json" ] + observatory_sources
 
   output = "$target_gen_dir/observatory/web/main.dart.js"
   outputs = [ output ]
@@ -24,7 +24,7 @@
   args = [
     "-o",
     rebase_path(output),
-    "--packages=" + rebase_path("../../.packages"),
+    "--packages=" + rebase_path("../../.dart_tool/package_config.json"),
   ]
   if (is_debug) {
     args += [ "--enable-asserts" ]
diff --git a/runtime/vm/os_thread.h b/runtime/vm/os_thread.h
index b1019e8..1f6a0e3 100644
--- a/runtime/vm/os_thread.h
+++ b/runtime/vm/os_thread.h
@@ -305,8 +305,9 @@
 
   friend class IsolateGroup;  // to access set_thread(Thread*).
   friend class OSThreadIterator;
-  friend class ThreadInterrupterWin;
   friend class ThreadInterrupterFuchsia;
+  friend class ThreadInterrupterMacOS;
+  friend class ThreadInterrupterWin;
   friend class ThreadPool;  // to access owning_thread_pool_worker_
 };
 
diff --git a/runtime/vm/signal_handler_macos.cc b/runtime/vm/signal_handler_macos.cc
index 70e5319..0e0c591 100644
--- a/runtime/vm/signal_handler_macos.cc
+++ b/runtime/vm/signal_handler_macos.cc
@@ -91,24 +91,11 @@
 }
 
 void SignalHandler::Install(SignalAction action) {
-  struct sigaction act = {};
-  act.sa_handler = NULL;
-  act.sa_sigaction = action;
-  sigemptyset(&act.sa_mask);
-  act.sa_flags = SA_RESTART | SA_SIGINFO;
-  int r = sigaction(SIGPROF, &act, NULL);
-  ASSERT(r == 0);
+  // Nothing to do on MacOS.
 }
 
 void SignalHandler::Remove() {
-  // Ignore future SIGPROF signals because by default SIGPROF will terminate
-  // the process and we may have some signals in flight.
-  struct sigaction act = {};
-  act.sa_handler = SIG_IGN;
-  sigemptyset(&act.sa_mask);
-  act.sa_flags = 0;
-  int r = sigaction(SIGPROF, &act, NULL);
-  ASSERT(r == 0);
+  // Nothing to do on MacOS.
 }
 
 }  // namespace dart
diff --git a/runtime/vm/thread_interrupter.cc b/runtime/vm/thread_interrupter.cc
index be990ab..978b428 100644
--- a/runtime/vm/thread_interrupter.cc
+++ b/runtime/vm/thread_interrupter.cc
@@ -66,15 +66,6 @@
 
 void ThreadInterrupter::Startup() {
   ASSERT(initialized_);
-  if (IsDebuggerAttached()) {
-    MonitorLocker shutdown_ml(monitor_);
-    shutdown_ = true;
-    if (FLAG_trace_thread_interrupter) {
-      OS::PrintErr(
-          "ThreadInterrupter disabled because a debugger is attached.\n");
-    }
-    return;
-  }
   if (FLAG_trace_thread_interrupter) {
     OS::PrintErr("ThreadInterrupter starting up.\n");
   }
diff --git a/runtime/vm/thread_interrupter.h b/runtime/vm/thread_interrupter.h
index c5d770e..8921ebe 100644
--- a/runtime/vm/thread_interrupter.h
+++ b/runtime/vm/thread_interrupter.h
@@ -102,8 +102,6 @@
   static std::atomic<intptr_t> sample_buffer_lock_;
   static std::atomic<intptr_t> sample_buffer_waiters_;
 
-  static bool IsDebuggerAttached();
-
   static bool InDeepSleep() {
     return current_wait_time_ == Monitor::kNoTimeout;
   }
diff --git a/runtime/vm/thread_interrupter_android.cc b/runtime/vm/thread_interrupter_android.cc
index dbdd331..2f8ed98 100644
--- a/runtime/vm/thread_interrupter_android.cc
+++ b/runtime/vm/thread_interrupter_android.cc
@@ -61,10 +61,6 @@
 #endif
 }  // namespace
 
-bool ThreadInterrupter::IsDebuggerAttached() {
-  return false;
-}
-
 void ThreadInterrupter::InterruptThread(OSThread* thread) {
   if (FLAG_trace_thread_interrupter) {
     OS::PrintErr("ThreadInterrupter interrupting %p\n",
diff --git a/runtime/vm/thread_interrupter_fuchsia.cc b/runtime/vm/thread_interrupter_fuchsia.cc
index b295569..235bbed 100644
--- a/runtime/vm/thread_interrupter_fuchsia.cc
+++ b/runtime/vm/thread_interrupter_fuchsia.cc
@@ -227,10 +227,6 @@
   }
 };
 
-bool ThreadInterrupter::IsDebuggerAttached() {
-  return false;
-}
-
 void ThreadInterrupter::InterruptThread(OSThread* thread) {
   if (FLAG_trace_thread_interrupter) {
     OS::PrintErr("ThreadInterrupter suspending %p\n",
diff --git a/runtime/vm/thread_interrupter_linux.cc b/runtime/vm/thread_interrupter_linux.cc
index ee623db..5d7661d 100644
--- a/runtime/vm/thread_interrupter_linux.cc
+++ b/runtime/vm/thread_interrupter_linux.cc
@@ -48,10 +48,6 @@
   }
 };
 
-bool ThreadInterrupter::IsDebuggerAttached() {
-  return false;
-}
-
 void ThreadInterrupter::InterruptThread(OSThread* thread) {
   if (FLAG_trace_thread_interrupter) {
     OS::PrintErr("ThreadInterrupter interrupting %p\n",
diff --git a/runtime/vm/thread_interrupter_macos.cc b/runtime/vm/thread_interrupter_macos.cc
index ba9ce5a..4a1cb85 100644
--- a/runtime/vm/thread_interrupter_macos.cc
+++ b/runtime/vm/thread_interrupter_macos.cc
@@ -5,12 +5,15 @@
 #include "platform/globals.h"
 #if defined(DART_HOST_OS_MACOS)
 
-#include <assert.h>      // NOLINT
-#include <errno.h>       // NOLINT
-#include <stdbool.h>     // NOLINT
-#include <sys/sysctl.h>  // NOLINT
-#include <sys/types.h>   // NOLINT
-#include <unistd.h>      // NOLINT
+#include <assert.h>            // NOLINT
+#include <errno.h>             // NOLINT
+#include <mach/kern_return.h>  // NOLINT
+#include <mach/mach.h>         // NOLINT
+#include <mach/thread_act.h>   // NOLINT
+#include <stdbool.h>           // NOLINT
+#include <sys/sysctl.h>        // NOLINT
+#include <sys/types.h>         // NOLINT
+#include <unistd.h>            // NOLINT
 
 #include "vm/flags.h"
 #include "vm/os.h"
@@ -24,70 +27,110 @@
 
 DECLARE_FLAG(bool, trace_thread_interrupter);
 
-// Returns true if the current process is being debugged (either
-// running under the debugger or has a debugger attached post facto).
-// Code from https://developer.apple.com/library/content/qa/qa1361/_index.html
-bool ThreadInterrupter::IsDebuggerAttached() {
-  struct kinfo_proc info;
-  // Initialize the flags so that, if sysctl fails for some bizarre
-  // reason, we get a predictable result.
-  info.kp_proc.p_flag = 0;
-  // Initialize mib, which tells sysctl the info we want, in this case
-  // we're looking for information about a specific process ID.
-  int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PID, getpid()};
-  size_t size = sizeof(info);
+#if defined(HOST_ARCH_X64)
+#define THREAD_STATE_FLAVOR x86_THREAD_STATE64
+#define THREAD_STATE_FLAVOR_SIZE x86_THREAD_STATE64_COUNT
+typedef x86_thread_state64_t thread_state_flavor_t;
+#elif defined(HOST_ARCH_ARM64)
+#define THREAD_STATE_FLAVOR ARM_THREAD_STATE64
+#define THREAD_STATE_FLAVOR_SIZE ARM_THREAD_STATE64_COUNT
+typedef arm_thread_state64_t thread_state_flavor_t;
+#elif defined(HOST_ARCH_ARM)
+#define THREAD_STATE_FLAVOR ARM_THREAD_STATE32
+#define THREAD_STATE_FLAVOR_SIZE ARM_THREAD_STATE32_COUNT
+typedef arm_thread_state32_t thread_state_flavor_t;
+#else
+#error "Unsupported architecture."
+#endif  // HOST_ARCH_...
 
-  // Call sysctl.
-  size = sizeof(info);
-  int junk = sysctl(mib, sizeof(mib) / sizeof(*mib), &info, &size, NULL, 0);
-  ASSERT(junk == 0);
-  // We're being debugged if the P_TRACED flag is set.
-  return ((info.kp_proc.p_flag & P_TRACED) != 0);
-}
-
-class ThreadInterrupterMacOS : public AllStatic {
+class ThreadInterrupterMacOS {
  public:
-  static void ThreadInterruptSignalHandler(int signal,
-                                           siginfo_t* info,
-                                           void* context_) {
-    if (signal != SIGPROF) {
-      return;
-    }
-    Thread* thread = Thread::Current();
-    if (thread == NULL) {
-      return;
-    }
-    ThreadInterrupter::SampleBufferWriterScope scope;
-    if (!scope.CanSample()) {
-      return;
-    }
-    // Extract thread state.
-    ucontext_t* context = reinterpret_cast<ucontext_t*>(context_);
-    mcontext_t mcontext = context->uc_mcontext;
-    InterruptedThreadState its;
-    its.pc = SignalHandler::GetProgramCounter(mcontext);
-    its.fp = SignalHandler::GetFramePointer(mcontext);
-    its.csp = SignalHandler::GetCStackPointer(mcontext);
-    its.dsp = SignalHandler::GetDartStackPointer(mcontext);
-    its.lr = SignalHandler::GetLinkRegister(mcontext);
-    Profiler::SampleThread(thread, its);
+  explicit ThreadInterrupterMacOS(OSThread* os_thread) : os_thread_(os_thread) {
+    ASSERT(os_thread != nullptr);
+    mach_thread_ = pthread_mach_thread_np(os_thread->id());
+    ASSERT(reinterpret_cast<void*>(mach_thread_) != nullptr);
+    res = thread_suspend(mach_thread_);
   }
+
+  void CollectSample() {
+    if (res != KERN_SUCCESS) {
+      return;
+    }
+    auto count = static_cast<mach_msg_type_number_t>(THREAD_STATE_FLAVOR_SIZE);
+    thread_state_flavor_t state;
+    kern_return_t res =
+        thread_get_state(mach_thread_, THREAD_STATE_FLAVOR,
+                         reinterpret_cast<thread_state_t>(&state), &count);
+    ASSERT(res == KERN_SUCCESS);
+    Thread* thread = static_cast<Thread*>(os_thread_->thread());
+    if (thread == nullptr) {
+      return;
+    }
+    Profiler::SampleThread(thread, ProcessState(state));
+  }
+
+  ~ThreadInterrupterMacOS() {
+    if (res != KERN_SUCCESS) {
+      return;
+    }
+    res = thread_resume(mach_thread_);
+    ASSERT(res == KERN_SUCCESS);
+  }
+
+ private:
+  static InterruptedThreadState ProcessState(thread_state_flavor_t state) {
+    InterruptedThreadState its;
+#if defined(HOST_ARCH_X64)
+    its.pc = state.__rip;
+    its.fp = state.__rbp;
+    its.csp = state.__rsp;
+    its.dsp = state.__rsp;
+    its.lr = 0;
+#elif defined(HOST_ARCH_ARM64)
+    its.pc = state.__pc;
+    its.fp = state.__fp;
+    its.csp = state.__sp;
+    its.dsp = state.__sp;
+    its.lr = state.__lr;
+#elif defined(HOST_ARCH_ARM)
+    its.pc = state.__pc;
+    its.fp = state.__fp;
+    its.csp = state.__sp;
+    its.dsp = state.__sp;
+    its.lr = state.__lr;
+#endif  // HOST_ARCH_...
+
+#if defined(TARGET_ARCH_ARM64) && !defined(USING_SIMULATOR)
+    its.dsp = state.__x[SPREG];
+#endif
+    return its;
+  }
+
+  kern_return_t res;
+  OSThread* os_thread_;
+  mach_port_t mach_thread_;
 };
 
-void ThreadInterrupter::InterruptThread(OSThread* thread) {
+void ThreadInterrupter::InterruptThread(OSThread* os_thread) {
+  ASSERT(!OSThread::Compare(OSThread::GetCurrentThreadId(), os_thread->id()));
   if (FLAG_trace_thread_interrupter) {
-    OS::PrintErr("ThreadInterrupter interrupting %p\n", thread->id());
+    OS::PrintErr("ThreadInterrupter interrupting %p\n", os_thread->id());
   }
-  int result = pthread_kill(thread->id(), SIGPROF);
-  ASSERT((result == 0) || (result == ESRCH));
+
+  ThreadInterrupter::SampleBufferWriterScope scope;
+  if (!scope.CanSample()) {
+    return;
+  }
+  ThreadInterrupterMacOS interrupter(os_thread);
+  interrupter.CollectSample();
 }
 
 void ThreadInterrupter::InstallSignalHandler() {
-  SignalHandler::Install(&ThreadInterrupterMacOS::ThreadInterruptSignalHandler);
+  // Nothing to do on MacOS.
 }
 
 void ThreadInterrupter::RemoveSignalHandler() {
-  SignalHandler::Remove();
+  // Nothing to do on MacOS.
 }
 
 #endif  // !PRODUCT
diff --git a/runtime/vm/thread_interrupter_win.cc b/runtime/vm/thread_interrupter_win.cc
index bfbf5d1..3db5023 100644
--- a/runtime/vm/thread_interrupter_win.cc
+++ b/runtime/vm/thread_interrupter_win.cc
@@ -90,10 +90,6 @@
   }
 };
 
-bool ThreadInterrupter::IsDebuggerAttached() {
-  return false;
-}
-
 void ThreadInterrupter::InterruptThread(OSThread* thread) {
   if (FLAG_trace_thread_interrupter) {
     OS::PrintErr("ThreadInterrupter suspending %p\n",
diff --git a/tools/VERSION b/tools/VERSION
index c6199a3..3ce629c 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 15
 PATCH 0
-PRERELEASE 212
+PRERELEASE 213
 PRERELEASE_PATCH 0
\ No newline at end of file
diff --git a/tools/bots/flutter/compile_flutter.sh b/tools/bots/flutter/compile_flutter.sh
index 35c3e81..511855c 100755
--- a/tools/bots/flutter/compile_flutter.sh
+++ b/tools/bots/flutter/compile_flutter.sh
@@ -83,7 +83,7 @@
 mkdir flutter_patched_sdk
 
 $checkout/tools/sdks/dart-sdk/bin/dart \
-    --packages=$checkout/.packages \
+    --packages=$checkout/.dart_tool/package_config.json \
     $checkout/pkg/front_end/tool/_fasta/compile_platform.dart \
     dart:core \
     -Ddart.vm.product=false \
@@ -97,7 +97,7 @@
     vm_outline_strong.dill
 
 $checkout/tools/sdks/dart-sdk/bin/dart \
-    --packages=$checkout/.packages \
+    --packages=$checkout/.dart_tool/package_config.json \
     $checkout/pkg/front_end/tool/_fasta/compile_platform.dart \
     --nnbd-agnostic \
     --target=flutter \
diff --git a/utils/compile_platform.gni b/utils/compile_platform.gni
index 37c3407..0523ac3 100644
--- a/utils/compile_platform.gni
+++ b/utils/compile_platform.gni
@@ -46,7 +46,7 @@
     }
     script = "$_dart_root/pkg/front_end/tool/_fasta/compile_platform.dart"
 
-    packages = "$_dart_root/.packages"
+    packages = "$_dart_root/.dart_tool/package_config.json"
 
     outputs = invoker.outputs
 
diff --git a/utils/compiler/BUILD.gn b/utils/compiler/BUILD.gn
index e724494..90190b8 100644
--- a/utils/compiler/BUILD.gn
+++ b/utils/compiler/BUILD.gn
@@ -41,7 +41,7 @@
 
   outputs = [ "$target_gen_dir/dart2js.dart" ]
 
-  packages = "../../.packages"
+  packages = "../../.dart_tool/package_config.json"
 
   args = [ "--output_dir=$output_dir" ]
 }
@@ -63,7 +63,7 @@
   vm_args = []
   main_dart = "$target_gen_dir/dart2js.dart"
   training_args = [
-    "--packages=" + rebase_path("../../.packages"),
+    "--packages=" + rebase_path("../../.dart_tool/package_config.json"),
     "--libraries-spec=" + rebase_path("$sdk_root/lib/libraries.json"),
 
     # Specifying the platform explicitly elides running the CFE on the sdk
diff --git a/utils/dartanalyzer/BUILD.gn b/utils/dartanalyzer/BUILD.gn
index b7d2486..87291fd 100644
--- a/utils/dartanalyzer/BUILD.gn
+++ b/utils/dartanalyzer/BUILD.gn
@@ -40,7 +40,7 @@
     "../../sdk:write_version_file",
   ]
   script = "../../pkg/analyzer/tool/summary/build_sdk_summaries.dart"
-  packages = "../../.packages"
+  packages = "../../.dart_tool/package_config.json"
   output = "$root_gen_dir/strong.sum"
   outputs = [ output ]
   vm_args = [ "-Dsdk_hash=$sdk_hash" ]
diff --git a/utils/dartdevc/BUILD.gn b/utils/dartdevc/BUILD.gn
index 74c0cc3..67e0411 100644
--- a/utils/dartdevc/BUILD.gn
+++ b/utils/dartdevc/BUILD.gn
@@ -59,7 +59,7 @@
 
     script = "../../pkg/compiler/lib/src/dart2js.dart"
 
-    packages = "../../.packages"
+    packages = "../../.dart_tool/package_config.json"
 
     vm_args = [ "-Dsdk_hash=$sdk_hash" ]
 
diff --git a/utils/gen_kernel/BUILD.gn b/utils/gen_kernel/BUILD.gn
index 0df5722..8206342 100644
--- a/utils/gen_kernel/BUILD.gn
+++ b/utils/gen_kernel/BUILD.gn
@@ -14,7 +14,7 @@
   ]
   gen_kernel_script = "$_dart_root/pkg/vm/bin/gen_kernel.dart"
   platform_dill = "$root_out_dir/vm_platform_strong.dill"
-  dot_packages = rebase_path("$_dart_root/.packages")
+  dot_packages = rebase_path("$_dart_root/.dart_tool/package_config.json")
 
   inputs = [
     gen_kernel_script,
diff --git a/utils/kernel-service/BUILD.gn b/utils/kernel-service/BUILD.gn
index 4d464c4..506dd49 100644
--- a/utils/kernel-service/BUILD.gn
+++ b/utils/kernel-service/BUILD.gn
@@ -101,7 +101,7 @@
           # consuming/producing kernel.
           "-Dsdk_hash=$sdk_hash",
 
-          "--packages=" + scheme + ":///.packages",
+          "--packages=" + scheme + ":///.dart_tool/package_config.json",
           "--platform=" + rebase_path("$root_out_dir/vm_platform_strong.dill"),
           "--filesystem-root=" + rebase_path("../../"),
           "--filesystem-scheme=" + scheme,