[dart2wasm] Update serialization strategy for dynamic modules.

Introduces some more machinery to simplify the serialization pipeline. Now the logic to index kernel nodes is hidden away in the serializer. Now throughout the compiler if entities (i.e. classes, members and references) need to be serialized they can be passed to the serializer directly.

Also adds support for tracking brand type assignments from the main module to the dynamic module. This is necessary to decouple the execution order of both compilations which is a WIP.

Change-Id: I38dd0ed11811ea12a2230959588b261719976592
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/412461
Reviewed-by: Martin Kustermann <[email protected]>
Commit-Queue: Nate Biggs <[email protected]>

Author: natebiggs

pkg/dart2wasm/lib/class_info.dart

@@ -373,6 +373,14 @@ class ClassInfoCollector {
         // conservative and mark it as not being final.
         struct.hasAnySubtypes = true;
       }
+
+      if (translator.isDynamicModule) {
+        final brandIndex =
+            translator.dynamicModuleInfo!.classMetadata[cls]?.brandIndex;
+        if (brandIndex != null) {
+          translator.typesBuilder.addBrandTypeAssignment(struct, brandIndex);
+        }
+      }
     }
     translator.classesSupersFirst.add(info);
     translator.classInfo[cls] = info;
@@ -700,9 +708,10 @@ class ClassIdNumbering {
     final implementors = <Class, List<Class>>{};
     final classIds = <Class, ClassId>{};
 
-    final savedMapping = translator.dynamicModuleInfo?.classIdMapping;
-    if (savedMapping != null) {
-      savedMapping.forEach((cls, classId) {
+    if (translator.isDynamicModule) {
+      final savedMapping = translator.dynamicModuleInfo!.classMetadata;
+      savedMapping.forEach((cls, info) {
+        final classId = info.classId;
         classIds[cls] = AbsoluteClassId(classId);
         savedMaxClassId = max(savedMaxClassId ?? -2, classId);
         if (!cls.isAbstract && !cls.isAnonymousMixin) {
@@ -796,8 +805,7 @@ class ClassIdNumbering {
     }
 
     // Make a list of the depth-first pre-order traversal.
-    final dfsOrder =
-        translator.dynamicModuleInfo?.dfsOrderClassIds ?? <Class>[];
+    final dfsOrder = [...?translator.dynamicModuleInfo?.dfsOrderClassIds];
     final inDfsOrder = {...dfsOrder};
 
     // Maps any class to a dense range of concrete class ids that are subclasses
@@ -907,6 +915,9 @@ final class AbsoluteClassId extends ClassId {
   int get _localValue => value;
 
   AbsoluteClassId(this.value);
+
+  @override
+  String toString() => 'Absolute($value)';
 }
 
 final class RelativeClassId extends ClassId {
@@ -915,6 +926,9 @@ final class RelativeClassId extends ClassId {
   int get _localValue => relativeValue;
 
   RelativeClassId(this.relativeValue);
+
+  @override
+  String toString() => 'Relative($relativeValue)';
 }
 
 // A range of class ids, both ends inclusive.

pkg/dart2wasm/lib/compile.dart

@@ -158,17 +158,7 @@ Future<CompilationResult> compileToModule(
     compilerOptions.compileSdk = true;
   }
 
-  DynamicModuleMetadata? dynamicModuleMetadata;
   final dynamicMainModuleUri = options.dynamicModuleMainUri;
-  if (dynamicMainModuleUri != null && options.dynamicInterfaceUri == null) {
-    final filename = options.dynamicModuleMetadataFile ??
-        Uri.parse(
-            path.setExtension(dynamicMainModuleUri.toFilePath(), '.dyndata'));
-    final dynamicModuleMetadataBytes =
-        await File.fromUri(filename).readAsBytes();
-    final source = BinaryDataSource(dynamicModuleMetadataBytes);
-    dynamicModuleMetadata = DynamicModuleMetadata.deserialize(source);
-  }
 
   final dynamicModuleMainUri = await resolveUri(options.dynamicModuleMainUri);
   final dynamicInterfaceUri = await resolveUri(options.dynamicInterfaceUri);
@@ -177,10 +167,7 @@ Future<CompilationResult> compileToModule(
   final isDynamicModule =
       dynamicModuleMainUri != null && dynamicInterfaceUri == null;
   if (isDynamicModule) {
-    dynamicModuleMetadata!.verifyDynamicModuleOptions(options);
     compilerOptions.additionalDills.add(dynamicModuleMainUri);
-  } else if (isDynamicMainModule) {
-    DynamicModuleMetadata.verifyMainModuleOptions(options);
   }
 
   CompilerResult? compilerResult;
@@ -268,7 +255,20 @@ Future<CompilationResult> compileToModule(
 
   moduleStrategy.prepareComponent();
 
-  if (isDynamicMainModule) {
+  MainModuleMetadata mainModuleMetadata =
+      MainModuleMetadata.empty(options.translatorOptions, options.environment);
+
+  if (isDynamicModule) {
+    final filename = options.dynamicModuleMetadataFile ??
+        Uri.parse(
+            path.setExtension(dynamicMainModuleUri!.toFilePath(), '.dyndata'));
+    final dynamicModuleMetadataBytes =
+        await File.fromUri(filename).readAsBytes();
+    final source = DataDeserializer(dynamicModuleMetadataBytes, component);
+    mainModuleMetadata = MainModuleMetadata.deserialize(source);
+    mainModuleMetadata.verifyDynamicModuleOptions(options);
+  } else if (isDynamicMainModule) {
+    MainModuleMetadata.verifyMainModuleOptions(options);
     writeComponentToBinary(component, dynamicModuleMainUri.path,
         includeSource: false);
   }
@@ -301,9 +301,13 @@ Future<CompilationResult> compileToModule(
 
   final moduleOutputData = moduleStrategy.buildModuleOutputData();
 
+  if (isDynamicMainModule) {
+    mainModuleMetadata.initialize(component, coreTypes);
+  }
+
   var translator = Translator(component, coreTypes, libraryIndex, recordClasses,
       moduleOutputData, options.translatorOptions,
-      dynamicModuleMetadata: dynamicModuleMetadata,
+      mainModuleMetadata: mainModuleMetadata,
       enableDynamicModules: dynamicModuleMainUri != null);
 
   String? depFile = options.depFile;
@@ -341,9 +345,9 @@ Future<CompilationResult> compileToModule(
     final filename = options.dynamicModuleMetadataFile ??
         Uri.parse(
             path.setExtension(dynamicMainModuleUri!.toFilePath(), '.dyndata'));
-    final sink = BinaryDataSink();
-    translator.dynamicModuleInfo!.toMetadata(options).serialize(sink);
-    await File.fromUri(filename).writeAsBytes(sink.takeBytes());
+    final serializer = DataSerializer(translator.component);
+    translator.dynamicModuleInfo!.metadata.serialize(translator, serializer);
+    await File.fromUri(filename).writeAsBytes(serializer.takeBytes());
   }
 
   return CompilationSuccess(wasmModules, jsRuntime, supportJs);

pkg/dart2wasm/lib/dispatch_table.dart

@@ -397,7 +397,8 @@ class DispatchTable {
         (_dynamicMethods[member.name.text] ??= {}).add(selector);
       }
     }
-    final mainModuleIds = translator.dynamicModuleInfo?.selectorIds?[member];
+
+    final mainModuleIds = translator.dynamicModuleInfo?.selectorIds[member];
     if (mainModuleIds != null) {
       selector._mainModuleIds[member] =
           isGetter ? mainModuleIds.$1 : mainModuleIds.$2;