[cfe] Refactor FunctionNode.futureValueType into emitted value type

Previously we would encode the type of the value returned in `async` functions as the field `futureValueType` on `FunctionNode`. For all other kinds of functions, such as `sync`, `sync*`, and `async*`, that field would be null. This CL renames `futureValueType` into `emittedVAlueType`, and for functions of kinds `async`, `sync*`, and `async*` that is expected to be the type of values emitted via `return` or `yield` statements. For `sync` functions that field is supposed to contain `null`. In response to https://github.com/dart-lang/sdk/issues/54159 TEST=existing Change-Id: I1efdbcc4e75d150f5618c7ca50cfe49a0e54fce6 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/341662 Reviewed-by: Alexander Markov <alexmarkov@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com> Reviewed-by: Ömer Ağacan <omersa@google.com> Commit-Queue: Chloe Stefantsova <cstefantsova@google.com> Reviewed-by: Mayank Patke <fishythefish@google.com>
2024-09-15 21:40:07 +00:00 · 2023-12-19 08:44:43 +00:00 · 2023-12-19 08:44:43 +00:00 · 3eeba4a4e2
parent 8d8c4c6125
commit 3eeba4a4e2
755 changed files with 2289 additions and 2266 deletions
--- a/pkg/compiler/lib/src/ir/impact_data.dart
+++ b/pkg/compiler/lib/src/ir/impact_data.dart
@ -202,7 +202,7 @@ class ImpactBuilder extends StaticTypeVisitor implements ImpactRegistry {
        break;

      case ir.AsyncMarker.Async:
-        registerAsync(function.futureValueType!);
+        registerAsync(function.emittedValueType!);
        break;

      case ir.AsyncMarker.AsyncStar:
--- a/pkg/compiler/lib/src/js_model/element_map_impl.dart
+++ b/pkg/compiler/lib/src/js_model/element_map_impl.dart
@ -2254,7 +2254,7 @@ class JsElementEnvironment extends ElementEnvironment
        return _getSyncStarElementType(returnType);
      case AsyncMarker.ASYNC:
        return elementMap.getDartType(
-            getFunctionNode(elementMap, function)!.futureValueType!);
+            getFunctionNode(elementMap, function)!.emittedValueType!);
      case AsyncMarker.ASYNC_STAR:
        return _getAsyncStarElementType(returnType);
    }
--- a/pkg/compiler/lib/src/kernel/transformations/modular/async_lowering.dart
+++ b/pkg/compiler/lib/src/kernel/transformations/modular/async_lowering.dart
@ -36,7 +36,7 @@ class AsyncLowering {

  bool _shouldTryAsyncLowering(FunctionNode node) =>
      node.asyncMarker == AsyncMarker.Async &&
-      node.futureValueType != null &&
+      node.emittedValueType != null &&
      _functions.last.shouldLower;

  void enterFunction(FunctionNode node) {
@ -54,7 +54,7 @@ class AsyncLowering {

  void _wrapBodySync(FunctionNode node) {
    node.asyncMarker = AsyncMarker.Sync;
-    final futureValueType = node.futureValueType!;
+    final futureValueType = node.emittedValueType!;
    _updateFunctionBody(
        node,
        ReturnStatement(StaticInvocation(
@ -69,7 +69,7 @@ class AsyncLowering {
  }

  void _wrapReturns(_FunctionData functionData, FunctionNode node) {
-    final futureValueType = node.futureValueType!;
+    final futureValueType = node.emittedValueType!;
    for (final returnStatement in functionData.returnStatements) {
      final expression = returnStatement.expression;
      // Ensure the returned future has a runtime type (T) matching the
--- a/pkg/dart2wasm/lib/transformers.dart
+++ b/pkg/dart2wasm/lib/transformers.dart
@ -464,7 +464,7 @@ class _WasmTransformer extends Transformer {
              _addCompleterToController(controller, completer, fileOffset)),
          tryFinally,
        ]),
-        futureValueType: const VoidType(),
+        emittedValueType: const VoidType(),
        returnType: InterfaceType(
            coreTypes.futureClass, Nullability.nonNullable, [const VoidType()]),
        asyncMarker: AsyncMarker.Async,
@ -544,7 +544,7 @@ class _WasmTransformer extends Transformer {
          coreTypes.objectNullableRawType, Nullability.nonNullable),
      asyncMarker: AsyncMarker.Async,
      dartAsyncMarker: AsyncMarker.Async,
-      futureValueType: coreTypes.objectNullableRawType,
+      emittedValueType: coreTypes.objectNullableRawType,
    ));

    // Call `asyncMap`.
--- a/pkg/dev_compiler/lib/src/kernel/compiler.dart
+++ b/pkg/dev_compiler/lib/src/kernel/compiler.dart
@ -4192,7 +4192,7 @@ class ProgramCompiler extends ComputeOnceConstantVisitor<js_ast.Expression>
    // In the body of an `async`, `await` is generated simply as `yield`.
    var gen = emitGeneratorFn((_) => []);
    var returnType = _currentLibrary!.isNonNullableByDefault
-        ? function.futureValueType!
+        ? function.emittedValueType!
        // Otherwise flatten the return type because futureValueType(T) is not
        // defined for legacy libraries.
        : _types.flatten(function
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@ -1305,11 +1305,9 @@ class BodyBuilder extends StackListenerImpl
          asyncModifier,
          body);
      body = inferredFunctionBody.body;
-      function.futureValueType = inferredFunctionBody.futureValueType;
-      assert(
-          !(function.asyncMarker == AsyncMarker.Async &&
-              function.futureValueType == null),
-          "No future value type computed.");
+      function.emittedValueType = inferredFunctionBody.emittedValueType;
+      assert(function.asyncMarker == AsyncMarker.Sync ||
+          function.emittedValueType != null);
    }

    if (_context.returnType is! OmittedTypeBuilder) {
--- a/pkg/front_end/lib/src/fasta/type_inference/closure_context.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/closure_context.dart
@ -40,7 +40,7 @@ abstract class ClosureContext {
  /// the unknown type.
  DartType get yieldContext;

-  DartType? get futureValueType;
+  DartType? get emittedValueType;

  factory ClosureContext(InferenceVisitorBase inferrer, AsyncMarker asyncMarker,
      DartType returnContext, bool needToInferReturnType) {
@ -142,6 +142,9 @@ class _SyncClosureContext implements ClosureContext {
  @override
  DartType get yieldContext => const UnknownType();

+  @override
+  DartType? get emittedValueType => null;
+
  final DartType _declaredReturnType;

  final bool _needToInferReturnType;
@ -161,9 +164,6 @@ class _SyncClosureContext implements ClosureContext {
  /// being inferred.
  List<DartType>? _returnExpressionTypes;

-  @override
-  DartType? get futureValueType => null;
-
  _SyncClosureContext(this.inferrer, this._returnContext,
      this._declaredReturnType, this._needToInferReturnType) {
    if (_needToInferReturnType) {
@ -493,6 +493,9 @@ class _AsyncClosureContext implements ClosureContext {
  @override
  DartType get yieldContext => const UnknownType();

+  @override
+  DartType? emittedValueType;
+
  final DartType _declaredReturnType;

  final bool _needToInferReturnType;
@ -512,15 +515,12 @@ class _AsyncClosureContext implements ClosureContext {
  /// being inferred.
  List<DartType>? _returnExpressionTypes;

-  @override
-  DartType? futureValueType;
-
  _AsyncClosureContext(
      this.inferrer,
      this._returnContext,
      this._declaredReturnType,
      this._needToInferReturnType,
-      this.futureValueType) {
+      this.emittedValueType) {
    if (_needToInferReturnType) {
      _returnStatements = [];
      _returnExpressionTypes = [];
@ -531,14 +531,14 @@ class _AsyncClosureContext implements ClosureContext {
      DartType returnType, ReturnStatement statement, DartType expressionType) {
    if (inferrer.isNonNullableByDefault) {
      assert(
-          futureValueType != null, "Future value type has not been computed.");
+          emittedValueType != null, "Future value type has not been computed.");

      if (statement.expression == null) {
        // It is a compile-time error if s is `return;`, unless T_v is void,
        // dynamic, or Null.
-        if (futureValueType is VoidType ||
-            futureValueType is DynamicType ||
-            futureValueType is NullType) {
+        if (emittedValueType is VoidType ||
+            emittedValueType is DynamicType ||
+            emittedValueType is NullType) {
          // Valid return;
        } else {
          statement.expression = inferrer.helper.wrapInProblem(
@ -560,7 +560,7 @@ class _AsyncClosureContext implements ClosureContext {

        DartType flattenedExpressionType =
            inferrer.typeSchemaEnvironment.flatten(expressionType);
-        if (futureValueType is VoidType &&
+        if (emittedValueType is VoidType &&
            !(flattenedExpressionType is VoidType ||
                flattenedExpressionType is DynamicType ||
                flattenedExpressionType is NullType)) {
@ -573,8 +573,8 @@ class _AsyncClosureContext implements ClosureContext {
              statement.expression!.fileOffset,
              noLength)
            ..parent = statement;
-        } else if (!(futureValueType is VoidType ||
-                futureValueType is DynamicType) &&
+        } else if (!(emittedValueType is VoidType ||
+                emittedValueType is DynamicType) &&
            flattenedExpressionType is VoidType) {
          // It is a compile-time error if s is `return e;`, T_v is neither void
          // nor dynamic, and flatten(S) is void.
@ -588,13 +588,13 @@ class _AsyncClosureContext implements ClosureContext {
        } else if (flattenedExpressionType is! VoidType &&
            !inferrer.typeSchemaEnvironment
                .performNullabilityAwareSubtypeCheck(
-                    flattenedExpressionType, futureValueType!)
+                    flattenedExpressionType, emittedValueType!)
                .isSubtypeWhenUsingNullabilities()) {
          // It is a compile-time error if s is `return e;`, flatten(S) is not
          // void, S is not assignable to T_v, and flatten(S) is not a subtype
          // of T_v.
          statement.expression = inferrer.ensureAssignable(
-              futureValueType!, expressionType, statement.expression!,
+              emittedValueType!, expressionType, statement.expression!,
              fileOffset: statement.expression!.fileOffset,
              runtimeCheckedType:
                  inferrer.computeGreatestClosure2(_returnContext),
@ -831,10 +831,10 @@ class _AsyncClosureContext implements ClosureContext {
    }

    if (inferrer.isNonNullableByDefault) {
-      futureValueType =
+      emittedValueType =
          computeFutureValueType(inferrer.coreTypes, inferredType);
    } else {
-      futureValueType = inferrer.typeSchemaEnvironment.flatten(inferredType);
+      emittedValueType = inferrer.typeSchemaEnvironment.flatten(inferredType);
    }

    for (int i = 0; i < _returnStatements!.length; ++i) {
@ -915,21 +915,25 @@ class _SyncStarClosureContext implements ClosureContext {
  @override
  DartType get yieldContext => _yieldElementContext;

+  @override
+  DartType? get emittedValueType => _emittedValueType;
+
  final DartType _declaredReturnType;

+  DartType? _emittedValueType;
+
  final bool _needToInferReturnType;

  /// A list of return expression types in functions whose return type is
  /// being inferred.
  List<DartType>? _yieldElementTypes;

-  @override
-  DartType? get futureValueType => null;
-
  _SyncStarClosureContext(this.inferrer, this._yieldElementContext,
      this._declaredReturnType, this._needToInferReturnType) {
    if (_needToInferReturnType) {
      _yieldElementTypes = [];
+    } else {
+      _emittedValueType = inferrer.computeGreatestClosure(_yieldElementContext);
    }
  }

@ -1009,8 +1013,13 @@ class _SyncStarClosureContext implements ClosureContext {
      inferredType = inferrer.computeGreatestClosure2(_declaredReturnType);
    }

-    return demoteTypeInLibrary(inferredType,
+    DartType demotedType = demoteTypeInLibrary(inferredType,
        isNonNullableByDefault: inferrer.isNonNullableByDefault);
+    _emittedValueType = inferrer.getTypeArgumentOf(
+        inferrer.typeSchemaEnvironment.getUnionFreeType(demotedType,
+            isNonNullableByDefault: inferrer.isNonNullableByDefault),
+        inferrer.coreTypes.iterableClass);
+    return demotedType;
  }

  @override
@ -1050,21 +1059,25 @@ class _AsyncStarClosureContext implements ClosureContext {
  @override
  DartType get yieldContext => _yieldElementContext;

+  @override
+  DartType? get emittedValueType => _emittedValueType;
+
  final DartType _declaredReturnType;

+  DartType? _emittedValueType;
+
  final bool _needToInferReturnType;

  /// A list of return expression types in functions whose return type is
  /// being inferred.
  List<DartType>? _yieldElementTypes;

-  @override
-  DartType? get futureValueType => null;
-
  _AsyncStarClosureContext(this.inferrer, this._yieldElementContext,
      this._declaredReturnType, this._needToInferReturnType) {
    if (_needToInferReturnType) {
      _yieldElementTypes = [];
+    } else {
+      _emittedValueType = inferrer.computeGreatestClosure(_yieldElementContext);
    }
  }

@ -1142,8 +1155,13 @@ class _AsyncStarClosureContext implements ClosureContext {
      inferredType = inferrer.computeGreatestClosure2(_declaredReturnType);
    }

-    return demoteTypeInLibrary(inferredType,
+    DartType demotedType = demoteTypeInLibrary(inferredType,
        isNonNullableByDefault: inferrer.isNonNullableByDefault);
+    _emittedValueType = inferrer.getTypeArgumentOf(
+        inferrer.typeSchemaEnvironment.getUnionFreeType(demotedType,
+            isNonNullableByDefault: inferrer.isNonNullableByDefault),
+        inferrer.coreTypes.streamClass);
+    return demotedType;
  }

  @override
--- a/pkg/front_end/lib/src/fasta/type_inference/inference_visitor_base.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/inference_visitor_base.dart
@ -2326,11 +2326,7 @@ abstract class InferenceVisitorBase implements InferenceVisitor {
    }
    bodyResult = closureContext.handleImplicitReturn(
        this, function.body!, bodyResult, fileOffset);
-    function.futureValueType = closureContext.futureValueType;
-    assert(
-        !(function.asyncMarker == AsyncMarker.Async &&
-            function.futureValueType == null),
-        "No future value type computed.");
+    function.emittedValueType = closureContext.emittedValueType;

    if (bodyResult.hasChanged) {
      function.body = bodyResult.statement..parent = function;
@ -3778,7 +3774,7 @@ abstract class InferenceVisitorBase implements InferenceVisitor {

  /// Computes the `futureValueTypeSchema` for the type schema [type].
  ///
-  /// This is the same as the [futureValueType] except that this handles
+  /// This is the same as the [emittedValueType] except that this handles
  /// the unknown type.
  DartType computeFutureValueTypeSchema(DartType type) {
    return type.accept1(new FutureValueTypeVisitor(unhandledTypeHandler:
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
@ -206,12 +206,11 @@ class TypeInferrerImpl implements TypeInferrer {
    result =
        closureContext.handleImplicitReturn(visitor, body, result, fileOffset);
    visitor.checkCleanState();
-    DartType? futureValueType = closureContext.futureValueType;
-    assert(!(asyncMarker == AsyncMarker.Async && futureValueType == null),
-        "No future value type computed.");
+    DartType? emittedValueType = closureContext.emittedValueType;
+    assert(asyncMarker == AsyncMarker.Sync || emittedValueType != null);
    flowAnalysis.finish();
    return new InferredFunctionBody(
-        result.hasChanged ? result.statement : body, futureValueType);
+        result.hasChanged ? result.statement : body, emittedValueType);
  }

  @override
@ -432,7 +431,7 @@ class TypeInferrerImplBenchmarked implements TypeInferrer {

 class InferredFunctionBody {
  final Statement body;
-  final DartType? futureValueType;
+  final DartType? emittedValueType;

-  InferredFunctionBody(this.body, this.futureValueType);
+  InferredFunctionBody(this.body, this.emittedValueType);
 }
--- a/pkg/front_end/test/macros/incremental/data/tests/user_macro/main.0.dart.expect
+++ b/pkg/front_end/test/macros/incremental/data/tests/user_macro/main.0.dart.expect
@ -36,7 +36,7 @@ macro class MethodMacro extends core::Object implements api::ClassDeclarationsMa
    : super core::Object::•()
    ;
  @#C2
-  method buildDeclarationsForClass(api::ClassDeclaration clazz, api::MemberDeclarationBuilder builder) → FutureOr<void> async /* futureValueType= void */ {}
+  method buildDeclarationsForClass(api::ClassDeclaration clazz, api::MemberDeclarationBuilder builder) → FutureOr<void> async /* emittedValueType= void */ {}
 }

 library;
--- a/pkg/front_end/test/macros/incremental/data/tests/user_macro/main.1.dart.expect
+++ b/pkg/front_end/test/macros/incremental/data/tests/user_macro/main.1.dart.expect
@ -33,7 +33,7 @@ macro class MethodMacro extends core::Object implements api::ClassDeclarationsMa
    : super core::Object::•()
    ;
  @#C2
-  method buildDeclarationsForClass(api::ClassDeclaration clazz, api::MemberDeclarationBuilder builder) → FutureOr<void> async /* futureValueType= void */ {
+  method buildDeclarationsForClass(api::ClassDeclaration clazz, api::MemberDeclarationBuilder builder) → FutureOr<void> async /* emittedValueType= void */ {
    builder.{api::MemberDeclarationBuilder::declareInType}(new api::DeclarationCode::fromString(mac2::generateBody())){(api::DeclarationCode) → void};
  }
 }
--- a/pkg/front_end/test/macros/incremental/data/tests/user_macro/main.2.dart.expect
+++ b/pkg/front_end/test/macros/incremental/data/tests/user_macro/main.2.dart.expect
@ -35,7 +35,7 @@ macro class MethodMacro extends core::Object implements api::ClassDeclarationsMa
    : super core::Object::•()
    ;
  @#C2
-  method buildDeclarationsForClass(api::ClassDeclaration clazz, api::MemberDeclarationBuilder builder) → FutureOr<void> async /* futureValueType= void */ {
+  method buildDeclarationsForClass(api::ClassDeclaration clazz, api::MemberDeclarationBuilder builder) → FutureOr<void> async /* emittedValueType= void */ {
    builder.{api::MemberDeclarationBuilder::declareInType}(new api::DeclarationCode::fromString(mac2::generateBody())){(api::DeclarationCode) → void};
  }
 }
--- a/pkg/front_end/test/static_types/static_type_test.dart
+++ b/pkg/front_end/test/static_types/static_type_test.dart
@ -96,8 +96,8 @@ class StaticTypeDataExtractor extends CfeDataExtractor<String> {

  @override
  String? computeMemberValue(Id id, Member node) {
-    if (node is Procedure && node.function.futureValueType != null) {
-      return 'futureValueType=${typeToText(node.function.futureValueType!)}';
+    if (node is Procedure && node.function.emittedValueType != null) {
+      return 'futureValueType=${typeToText(node.function.emittedValueType!)}';
    }
    return null;
  }
@ -109,9 +109,10 @@ class StaticTypeDataExtractor extends CfeDataExtractor<String> {
    }
    if (node is Expression) {
      DartType type = node.getStaticType(_staticTypeContext!);
-      if (node is FunctionExpression && node.function.futureValueType != null) {
+      if (node is FunctionExpression &&
+          node.function.emittedValueType != null) {
        return '${typeToText(type)},'
-            'futureValueType=${typeToText(node.function.futureValueType!)}';
+            'futureValueType=${typeToText(node.function.emittedValueType!)}';
      }
      return typeToText(type);
    } else if (node is Arguments) {
@ -123,8 +124,8 @@ class StaticTypeDataExtractor extends CfeDataExtractor<String> {
        return typeToText(node.getElementType(_staticTypeContext!));
      }
    } else if (node is FunctionDeclaration) {
-      if (node.function.futureValueType != null) {
-        return 'futureValueType=${typeToText(node.function.futureValueType!)}';
+      if (node.function.emittedValueType != null) {
+        return 'futureValueType=${typeToText(node.function.emittedValueType!)}';
      }
    }
    return null;
--- a/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.strong.expect
@ -6,15 +6,15 @@ import "dart:core" as core;
 static method bar() → asy::Future<core::int> {
  return asy::Future::value<core::int>(123);
 }
-static method foo1() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo1() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return await self::bar();
 }
-static method foo2(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return await asy::Future::value<core::int>(345);
  return await self::bar();
 }
-static method foo3(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo3(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return 234;
  return await asy::Future::value<core::int>(123);
--- a/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.strong.transformed.expect
@ -6,17 +6,17 @@ import "dart:core" as core;
 static method bar() → asy::Future<core::int> {
  return asy::Future::value<core::int>(123);
 }
-static method foo1() → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo1() → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    return asy::Future::value<core::int>(self::bar());
  });
-static method foo2(core::bool x) → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo2(core::bool x) → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    if(x)
      return asy::Future::value<core::int>(asy::Future::value<core::int>(345));
    return asy::Future::value<core::int>(self::bar());
  });
-static method foo3(core::bool x) → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo3(core::bool x) → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    if(x)
      return asy::Future::value<core::int>(234);
--- a/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.weak.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.weak.expect
@ -6,15 +6,15 @@ import "dart:core" as core;
 static method bar() → asy::Future<core::int> {
  return asy::Future::value<core::int>(123);
 }
-static method foo1() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo1() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return await self::bar();
 }
-static method foo2(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return await asy::Future::value<core::int>(345);
  return await self::bar();
 }
-static method foo3(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo3(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return 234;
  return await asy::Future::value<core::int>(123);
--- a/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.weak.modular.expect
@ -6,15 +6,15 @@ import "dart:core" as core;
 static method bar() → asy::Future<core::int> {
  return asy::Future::value<core::int>(123);
 }
-static method foo1() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo1() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return await self::bar();
 }
-static method foo2(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return await asy::Future::value<core::int>(345);
  return await self::bar();
 }
-static method foo3(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo3(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return 234;
  return await asy::Future::value<core::int>(123);
--- a/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart.weak.transformed.expect
@ -6,17 +6,17 @@ import "dart:core" as core;
 static method bar() → asy::Future<core::int> {
  return asy::Future::value<core::int>(123);
 }
-static method foo1() → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo1() → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    return asy::Future::value<core::int>(self::bar());
  });
-static method foo2(core::bool x) → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo2(core::bool x) → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    if(x)
      return asy::Future::value<core::int>(asy::Future::value<core::int>(345));
    return asy::Future::value<core::int>(self::bar());
  });
-static method foo3(core::bool x) → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo3(core::bool x) → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    if(x)
      return asy::Future::value<core::int>(234);
--- a/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.strong.expect
@ -3,7 +3,7 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
--- a/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.strong.transformed.expect
@ -3,7 +3,7 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
--- a/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.weak.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.weak.expect
@ -3,7 +3,7 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
--- a/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.weak.modular.expect
@ -3,7 +3,7 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
--- a/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart.weak.transformed.expect
@ -3,7 +3,7 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.strong.expect
@ -3,25 +3,25 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo1() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
-static method foo2() → asy::Future<void> async /* futureValueType= void */ {
+static method foo2() → asy::Future<void> async /* emittedValueType= void */ {
  final core::int c = 3;
 }
-static method foo3() → dynamic async /* futureValueType= dynamic */ {
+static method foo3() → dynamic async /* emittedValueType= dynamic */ {
  return 234;
 }
 static method bar(() → asy::Future<core::int> func) → void {
  func(){() → asy::Future<core::int>};
 }
-static method foo4() → asy::Future<core::bool> async /* futureValueType= core::bool */ {
+static method foo4() → asy::Future<core::bool> async /* emittedValueType= core::bool */ {
  await asy::Future::value<core::int>(2);
-  self::bar(() → asy::Future<core::int> async /* futureValueType= core::int */ => 3);
+  self::bar(() → asy::Future<core::int> async /* emittedValueType= core::int */ => 3);
  return true;
 }
-static method foo5(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return 123;
  return 234;
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.strong.transformed.expect
@ -3,28 +3,28 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo1() → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    final core::int c = 3;
    return asy::Future::value<core::int>(c);
  });
-static method foo2() → asy::Future<void> /* futureValueType= void */ /* originally async */ 
+static method foo2() → asy::Future<void> /* emittedValueType= void */ /* originally async */ 
  return asy::Future::sync<void>(() → FutureOr<void>? {
    final core::int c = 3;
  });
-static method foo3() → dynamic /* futureValueType= dynamic */ /* originally async */ 
+static method foo3() → dynamic /* emittedValueType= dynamic */ /* originally async */ 
  return asy::Future::sync<dynamic>(() → FutureOr<dynamic>? {
    return asy::Future::value<dynamic>(234);
  });
 static method bar(() → asy::Future<core::int> func) → void {
  func(){() → asy::Future<core::int>};
 }
-static method foo4() → asy::Future<core::bool> async /* futureValueType= core::bool */ {
+static method foo4() → asy::Future<core::bool> async /* emittedValueType= core::bool */ {
  await asy::Future::value<core::int>(2);
-  self::bar(() → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ => asy::Future::sync<core::int>(() → FutureOr<core::int> => asy::Future::value<core::int>(3)));
+  self::bar(() → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ => asy::Future::sync<core::int>(() → FutureOr<core::int> => asy::Future::value<core::int>(3)));
  return true;
 }
-static method foo5(core::bool x) → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo5(core::bool x) → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    if(x)
      return asy::Future::value<core::int>(123);
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.weak.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.weak.expect
@ -3,25 +3,25 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo1() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
-static method foo2() → asy::Future<void> async /* futureValueType= void */ {
+static method foo2() → asy::Future<void> async /* emittedValueType= void */ {
  final core::int c = 3;
 }
-static method foo3() → dynamic async /* futureValueType= dynamic */ {
+static method foo3() → dynamic async /* emittedValueType= dynamic */ {
  return 234;
 }
 static method bar(() → asy::Future<core::int> func) → void {
  func(){() → asy::Future<core::int>};
 }
-static method foo4() → asy::Future<core::bool> async /* futureValueType= core::bool */ {
+static method foo4() → asy::Future<core::bool> async /* emittedValueType= core::bool */ {
  await asy::Future::value<core::int>(2);
-  self::bar(() → asy::Future<core::int> async /* futureValueType= core::int */ => 3);
+  self::bar(() → asy::Future<core::int> async /* emittedValueType= core::int */ => 3);
  return true;
 }
-static method foo5(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return 123;
  return 234;
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.weak.modular.expect
@ -3,25 +3,25 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo1() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  final core::int c = 3;
  return c;
 }
-static method foo2() → asy::Future<void> async /* futureValueType= void */ {
+static method foo2() → asy::Future<void> async /* emittedValueType= void */ {
  final core::int c = 3;
 }
-static method foo3() → dynamic async /* futureValueType= dynamic */ {
+static method foo3() → dynamic async /* emittedValueType= dynamic */ {
  return 234;
 }
 static method bar(() → asy::Future<core::int> func) → void {
  func(){() → asy::Future<core::int>};
 }
-static method foo4() → asy::Future<core::bool> async /* futureValueType= core::bool */ {
+static method foo4() → asy::Future<core::bool> async /* emittedValueType= core::bool */ {
  await asy::Future::value<core::int>(2);
-  self::bar(() → asy::Future<core::int> async /* futureValueType= core::int */ => 3);
+  self::bar(() → asy::Future<core::int> async /* emittedValueType= core::int */ => 3);
  return true;
 }
-static method foo5(core::bool x) → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5(core::bool x) → asy::Future<core::int> async /* emittedValueType= core::int */ {
  if(x)
    return 123;
  return 234;
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_await.dart.weak.transformed.expect
@ -3,28 +3,28 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo1() → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    final core::int c = 3;
    return asy::Future::value<core::int>(c);
  });
-static method foo2() → asy::Future<void> /* futureValueType= void */ /* originally async */ 
+static method foo2() → asy::Future<void> /* emittedValueType= void */ /* originally async */ 
  return asy::Future::sync<void>(() → FutureOr<void>? {
    final core::int c = 3;
  });
-static method foo3() → dynamic /* futureValueType= dynamic */ /* originally async */ 
+static method foo3() → dynamic /* emittedValueType= dynamic */ /* originally async */ 
  return asy::Future::sync<dynamic>(() → FutureOr<dynamic>? {
    return asy::Future::value<dynamic>(234);
  });
 static method bar(() → asy::Future<core::int> func) → void {
  func(){() → asy::Future<core::int>};
 }
-static method foo4() → asy::Future<core::bool> async /* futureValueType= core::bool */ {
+static method foo4() → asy::Future<core::bool> async /* emittedValueType= core::bool */ {
  await asy::Future::value<core::int>(2);
-  self::bar(() → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ => asy::Future::sync<core::int>(() → FutureOr<core::int> => asy::Future::value<core::int>(3)));
+  self::bar(() → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ => asy::Future::sync<core::int>(() → FutureOr<core::int> => asy::Future::value<core::int>(3)));
  return true;
 }
-static method foo5(core::bool x) → asy::Future<core::int> /* futureValueType= core::int */ /* originally async */ 
+static method foo5(core::bool x) → asy::Future<core::int> /* emittedValueType= core::int */ /* originally async */ 
  return asy::Future::sync<core::int>(() → FutureOr<core::int> {
    if(x)
      return asy::Future::value<core::int>(123);
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.strong.expect
@ -3,19 +3,19 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<void> async /* futureValueType= void */ {
+static method foo1() → asy::Future<void> async /* emittedValueType= void */ {
  await 6 /* runtimeCheckType= asy::Future<core::int> */ ;
 }
-static method foo2() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return (await 6 /* runtimeCheckType= asy::Future<core::int> */ ).{core::num::+}(3){(core::num) → core::int};
 }
-static method foo3() → asy::Future<void> async /* futureValueType= void */ {
+static method foo3() → asy::Future<void> async /* emittedValueType= void */ {
  #L1:
  await for (final dynamic x in new asy::_EmptyStream::•<dynamic>()) {
    break #L1;
  }
 }
-static method foo4() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo4() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
@ -23,7 +23,7 @@ static method foo4() → asy::Future<core::int> async /* futureValueType= core::
    return 2;
  }
 }
-static method foo5() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.strong.transformed.expect
@ -3,19 +3,19 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<void> async /* futureValueType= void */ {
+static method foo1() → asy::Future<void> async /* emittedValueType= void */ {
  await asy::_wrapAwaitedExpression<core::int>(6);
 }
-static method foo2() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return (await asy::_wrapAwaitedExpression<core::int>(6)).{core::num::+}(3){(core::num) → core::int};
 }
-static method foo3() → asy::Future<void> async /* futureValueType= void */ {
+static method foo3() → asy::Future<void> async /* emittedValueType= void */ {
  #L1:
  await for (final dynamic x in new asy::_EmptyStream::•<dynamic>()) {
    break #L1;
  }
 }
-static method foo4() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo4() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
@ -23,7 +23,7 @@ static method foo4() → asy::Future<core::int> async /* futureValueType= core::
    return 2;
  }
 }
-static method foo5() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.weak.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.weak.expect
@ -3,19 +3,19 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<void> async /* futureValueType= void */ {
+static method foo1() → asy::Future<void> async /* emittedValueType= void */ {
  await 6 /* runtimeCheckType= asy::Future<core::int> */ ;
 }
-static method foo2() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return (await 6 /* runtimeCheckType= asy::Future<core::int> */ ).{core::num::+}(3){(core::num) → core::int};
 }
-static method foo3() → asy::Future<void> async /* futureValueType= void */ {
+static method foo3() → asy::Future<void> async /* emittedValueType= void */ {
  #L1:
  await for (final dynamic x in new asy::_EmptyStream::•<dynamic>()) {
    break #L1;
  }
 }
-static method foo4() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo4() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
@ -23,7 +23,7 @@ static method foo4() → asy::Future<core::int> async /* futureValueType= core::
    return 2;
  }
 }
-static method foo5() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.weak.modular.expect
@ -3,19 +3,19 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<void> async /* futureValueType= void */ {
+static method foo1() → asy::Future<void> async /* emittedValueType= void */ {
  await 6 /* runtimeCheckType= asy::Future<core::int> */ ;
 }
-static method foo2() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return (await 6 /* runtimeCheckType= asy::Future<core::int> */ ).{core::num::+}(3){(core::num) → core::int};
 }
-static method foo3() → asy::Future<void> async /* futureValueType= void */ {
+static method foo3() → asy::Future<void> async /* emittedValueType= void */ {
  #L1:
  await for (final dynamic x in new asy::_EmptyStream::•<dynamic>()) {
    break #L1;
  }
 }
-static method foo4() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo4() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
@ -23,7 +23,7 @@ static method foo4() → asy::Future<core::int> async /* futureValueType= core::
    return 2;
  }
 }
-static method foo5() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
--- a/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/dart2js/async_lowering/no_transform.dart.weak.transformed.expect
@ -3,19 +3,19 @@ import self as self;
 import "dart:async" as asy;
 import "dart:core" as core;

-static method foo1() → asy::Future<void> async /* futureValueType= void */ {
+static method foo1() → asy::Future<void> async /* emittedValueType= void */ {
  await asy::_wrapAwaitedExpression<core::int>(6);
 }
-static method foo2() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo2() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  return (await asy::_wrapAwaitedExpression<core::int>(6)).{core::num::+}(3){(core::num) → core::int};
 }
-static method foo3() → asy::Future<void> async /* futureValueType= void */ {
+static method foo3() → asy::Future<void> async /* emittedValueType= void */ {
  #L1:
  await for (final dynamic x in new asy::_EmptyStream::•<dynamic>()) {
    break #L1;
  }
 }
-static method foo4() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo4() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
@ -23,7 +23,7 @@ static method foo4() → asy::Future<core::int> async /* futureValueType= core::
    return 2;
  }
 }
-static method foo5() → asy::Future<core::int> async /* futureValueType= core::int */ {
+static method foo5() → asy::Future<core::int> async /* emittedValueType= core::int */ {
  try {
    return 3;
  }
--- a/pkg/front_end/testcases/dart2wasm/for_in.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2wasm/for_in.dart.strong.expect
@ -8,7 +8,7 @@ static method method(core::Iterable<core::int> iterable) → dynamic {
    core::print(i);
  }
 }
-static method asyncMethod(asy::Stream<core::int> stream) → dynamic async /* futureValueType= dynamic */ {
+static method asyncMethod(asy::Stream<core::int> stream) → dynamic async /* emittedValueType= dynamic */ {
  await for (core::int i in stream) {
    core::print(i);
  }
--- a/pkg/front_end/testcases/dart2wasm/for_in.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2wasm/for_in.dart.strong.transformed.expect
@ -14,7 +14,7 @@ static method method(core::Iterable<core::int> iterable) → dynamic {
    }
  }
 }
-static method asyncMethod(asy::Stream<core::int> stream) → dynamic async /* futureValueType= dynamic */ {
+static method asyncMethod(asy::Stream<core::int> stream) → dynamic async /* emittedValueType= dynamic */ {
  core::bool :async_temporary_0;
  dynamic :async_temporary_1;
  {
--- a/pkg/front_end/testcases/dart2wasm/issue54069.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2wasm/issue54069.dart.strong.expect
@ -8,14 +8,14 @@ import "dart:typed_data";

 static method getBinaryTestProto() → asy::Future<typ::Uint8List>
  return self::readFileWeb("test.binary.pb");
-static method readFileWeb(core::String path) → asy::Future<typ::Uint8List> async /* futureValueType= typ::Uint8List */ {
+static method readFileWeb(core::String path) → asy::Future<typ::Uint8List> async /* emittedValueType= typ::Uint8List */ {
  throw "";
 }
-static method runBench([typ::Uint8List? data = #C1]) → void async /* futureValueType= void */ {
+static method runBench([typ::Uint8List? data = #C1]) → void async /* emittedValueType= void */ {
  data == null ?{typ::Uint8List?} data = await self::getBinaryTestProto() : null;
  core::print(data{typ::Uint8List});
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  typ::Uint8List data = await self::getBinaryTestProto();
  core::print("File successfully read, contents: ${data}");
  self::runBench(data);
--- a/pkg/front_end/testcases/dart2wasm/issue54069.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2wasm/issue54069.dart.strong.transformed.expect
@ -8,10 +8,10 @@ import "dart:typed_data";

 static method getBinaryTestProto() → asy::Future<typ::Uint8List>
  return self::readFileWeb("test.binary.pb");
-static method readFileWeb(core::String path) → asy::Future<typ::Uint8List> async /* futureValueType= typ::Uint8List */ {
+static method readFileWeb(core::String path) → asy::Future<typ::Uint8List> async /* emittedValueType= typ::Uint8List */ {
  throw "";
 }
-static method runBench([typ::Uint8List? data = #C1]) → void async /* futureValueType= void */ {
+static method runBench([typ::Uint8List? data = #C1]) → void async /* emittedValueType= void */ {
  typ::Uint8List :async_temporary_0;
  typ::Uint8List? :async_temporary_1;
  if(data == null) {
@ -24,7 +24,7 @@ static method runBench([typ::Uint8List? data = #C1]) → void async /* futureVal
  :async_temporary_1 as{ForLegacy} dynamic;
  core::print(data{typ::Uint8List});
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  typ::Uint8List :async_temporary_0;
  :async_temporary_0 = await self::getBinaryTestProto();
  typ::Uint8List data = :async_temporary_0 as{ForLegacy} dynamic;
--- a/pkg/front_end/testcases/dart2wasm/yield.dart.strong.expect
+++ b/pkg/front_end/testcases/dart2wasm/yield.dart.strong.expect
@ -3,12 +3,12 @@ import self as self;
 import "dart:core" as core;
 import "dart:async" as asy;

-static method method(core::Iterable<core::int> iterable) → core::Iterable<core::int> sync* {
+static method method(core::Iterable<core::int> iterable) → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
  yield 1;
  yield 2;
  yield* iterable;
 }
-static method asyncMethod(asy::Stream<core::int> stream) → asy::Stream<core::int> async* {
+static method asyncMethod(asy::Stream<core::int> stream) → asy::Stream<core::int> async* /* emittedValueType= core::int */ {
  yield 1;
  yield 2;
  yield* stream;
--- a/pkg/front_end/testcases/dart2wasm/yield.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/dart2wasm/yield.dart.strong.transformed.expect
@ -3,14 +3,14 @@ import self as self;
 import "dart:core" as core;
 import "dart:async" as asy;

-static method method(core::Iterable<core::int> iterable) → core::Iterable<core::int> sync* {
+static method method(core::Iterable<core::int> iterable) → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
  yield 1;
  yield 2;
  yield* iterable;
 }
 static method asyncMethod(asy::Stream<core::int> stream) → asy::Stream<core::int> {
  synthesized asy::StreamController<core::Object?> #controller = asy::StreamController::•<core::Object?>();
-  synthesized () → asy::Future<void> #body = () → asy::Future<void> async /* futureValueType= void */ {
+  synthesized () → asy::Future<void> #body = () → asy::Future<void> async /* emittedValueType= void */ {
    core::bool :async_temporary_0;
    core::bool :async_temporary_1;
    core::bool :async_temporary_2;
@ -96,7 +96,7 @@ static method asyncMethod(asy::Stream<core::int> stream) → asy::Stream<core::i
  synthesized core::bool #isFirst = #C2;
  synthesized core::bool #isEven = #C1;
  #controller.{asy::StreamController::add}(#C3){(core::Object?) → void};
-  return #controller.{asy::StreamController::stream}{asy::Stream<core::Object?>}.{asy::Stream::asyncMap}<core::Object?>((synthesized core::Object? value) → FutureOr<core::Object?> async /* futureValueType= core::Object? */ {
+  return #controller.{asy::StreamController::stream}{asy::Stream<core::Object?>}.{asy::Stream::asyncMap}<core::Object?>((synthesized core::Object? value) → FutureOr<core::Object?> async /* emittedValueType= core::Object? */ {
    if(#isFirst) {
      #body(){() → asy::Future<void>};
      return #C3;
--- a/pkg/front_end/testcases/extension_types/await.dart.strong.expect
+++ b/pkg/front_end/testcases/extension_types/await.dart.strong.expect
@ -25,7 +25,7 @@ static extension-type-member method V2|constructor#<T extends asy::Future<core::
 }
 static extension-type-member method V2|constructor#_#new#tearOff<T extends asy::Future<core::Object>>(self::V2|constructor#_#new#tearOff::T id) → self::V2<self::V2|constructor#_#new#tearOff::T> /* = self::V2|constructor#_#new#tearOff::T */
  return self::V2|constructor#<self::V2|constructor#_#new#tearOff::T>(id);
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  self::V1 /* = asy::Future<core::int> */ v1 = self::V1|constructor#(asy::Future::value<core::int>(42));
  core::int _v1 = await v1;
  self::expect(42, _v1);
--- a/pkg/front_end/testcases/extension_types/await.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/await.dart.strong.transformed.expect
@ -25,7 +25,7 @@ static extension-type-member method V2|constructor#<T extends asy::Future<core::
 }
 static extension-type-member method V2|constructor#_#new#tearOff<T extends asy::Future<core::Object>>(self::V2|constructor#_#new#tearOff::T id) → self::V2<self::V2|constructor#_#new#tearOff::T> /* = self::V2|constructor#_#new#tearOff::T */
  return self::V2|constructor#<self::V2|constructor#_#new#tearOff::T>(id);
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  self::V1 /* = asy::Future<core::int> */ v1 = self::V1|constructor#(asy::Future::value<core::int>(42));
  core::int _v1 = await v1;
  self::expect(42, _v1);
--- a/pkg/front_end/testcases/extension_types/await.dart.weak.expect
+++ b/pkg/front_end/testcases/extension_types/await.dart.weak.expect
@ -25,7 +25,7 @@ static extension-type-member method V2|constructor#<T extends asy::Future<core::
 }
 static extension-type-member method V2|constructor#_#new#tearOff<T extends asy::Future<core::Object>>(self::V2|constructor#_#new#tearOff::T id) → self::V2<self::V2|constructor#_#new#tearOff::T> /* = self::V2|constructor#_#new#tearOff::T */
  return self::V2|constructor#<self::V2|constructor#_#new#tearOff::T>(id);
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  self::V1 /* = asy::Future<core::int> */ v1 = self::V1|constructor#(asy::Future::value<core::int>(42));
  core::int _v1 = await v1;
  self::expect(42, _v1);
--- a/pkg/front_end/testcases/extension_types/await.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extension_types/await.dart.weak.modular.expect
@ -25,7 +25,7 @@ static extension-type-member method V2|constructor#<T extends asy::Future<core::
 }
 static extension-type-member method V2|constructor#_#new#tearOff<T extends asy::Future<core::Object>>(self::V2|constructor#_#new#tearOff::T id) → self::V2<self::V2|constructor#_#new#tearOff::T> /* = self::V2|constructor#_#new#tearOff::T */
  return self::V2|constructor#<self::V2|constructor#_#new#tearOff::T>(id);
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  self::V1 /* = asy::Future<core::int> */ v1 = self::V1|constructor#(asy::Future::value<core::int>(42));
  core::int _v1 = await v1;
  self::expect(42, _v1);
--- a/pkg/front_end/testcases/extension_types/await.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/await.dart.weak.transformed.expect
@ -25,7 +25,7 @@ static extension-type-member method V2|constructor#<T extends asy::Future<core::
 }
 static extension-type-member method V2|constructor#_#new#tearOff<T extends asy::Future<core::Object>>(self::V2|constructor#_#new#tearOff::T id) → self::V2<self::V2|constructor#_#new#tearOff::T> /* = self::V2|constructor#_#new#tearOff::T */
  return self::V2|constructor#<self::V2|constructor#_#new#tearOff::T>(id);
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  self::V1 /* = asy::Future<core::int> */ v1 = self::V1|constructor#(asy::Future::value<core::int>(42));
  core::int _v1 = await v1;
  self::expect(42, _v1);
--- a/pkg/front_end/testcases/extension_types/issue53207.dart.strong.expect
+++ b/pkg/front_end/testcases/extension_types/issue53207.dart.strong.expect
@ -131,7 +131,7 @@ static extension-type-member method F4|constructor#<X extends asy::Future<core::
 }
 static extension-type-member method F4|constructor#_#new#tearOff<X extends asy::Future<core::num>>(self::F4|constructor#_#new#tearOff::X foo) → self::F4<self::F4|constructor#_#new#tearOff::X> /* = self::F4|constructor#_#new#tearOff::X */
  return self::F4|constructor#<self::F4|constructor#_#new#tearOff::X>(foo);
-static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* futureValueType= dynamic */ {
+static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* emittedValueType= dynamic */ {
  await invalid-expression "pkg/front_end/testcases/extension_types/issue53207.dart:21:9: Error: The 'await' expression can't be used for an expression with an extension type that is not a subtype of 'Future'.
  await e1; // Error.
        ^" in e1 /* runtimeCheckType= asy::Future<self::E1 /* = asy::Future<core::int> */> */ ;
--- a/pkg/front_end/testcases/extension_types/issue53207.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/issue53207.dart.strong.transformed.expect
@ -131,7 +131,7 @@ static extension-type-member method F4|constructor#<X extends asy::Future<core::
 }
 static extension-type-member method F4|constructor#_#new#tearOff<X extends asy::Future<core::num>>(self::F4|constructor#_#new#tearOff::X foo) → self::F4<self::F4|constructor#_#new#tearOff::X> /* = self::F4|constructor#_#new#tearOff::X */
  return self::F4|constructor#<self::F4|constructor#_#new#tearOff::X>(foo);
-static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* futureValueType= dynamic */ {
+static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* emittedValueType= dynamic */ {
  await invalid-expression "pkg/front_end/testcases/extension_types/issue53207.dart:21:9: Error: The 'await' expression can't be used for an expression with an extension type that is not a subtype of 'Future'.
  await e1; // Error.
        ^" in e1 /* runtimeCheckType= asy::Future<self::E1 /* = asy::Future<core::int> */> */ ;
--- a/pkg/front_end/testcases/extension_types/issue53207.dart.weak.expect
+++ b/pkg/front_end/testcases/extension_types/issue53207.dart.weak.expect
@ -131,7 +131,7 @@ static extension-type-member method F4|constructor#<X extends asy::Future<core::
 }
 static extension-type-member method F4|constructor#_#new#tearOff<X extends asy::Future<core::num>>(self::F4|constructor#_#new#tearOff::X foo) → self::F4<self::F4|constructor#_#new#tearOff::X> /* = self::F4|constructor#_#new#tearOff::X */
  return self::F4|constructor#<self::F4|constructor#_#new#tearOff::X>(foo);
-static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* futureValueType= dynamic */ {
+static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* emittedValueType= dynamic */ {
  await invalid-expression "pkg/front_end/testcases/extension_types/issue53207.dart:21:9: Error: The 'await' expression can't be used for an expression with an extension type that is not a subtype of 'Future'.
  await e1; // Error.
        ^" in e1 /* runtimeCheckType= asy::Future<self::E1 /* = asy::Future<core::int> */> */ ;
--- a/pkg/front_end/testcases/extension_types/issue53207.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extension_types/issue53207.dart.weak.modular.expect
@ -131,7 +131,7 @@ static extension-type-member method F4|constructor#<X extends asy::Future<core::
 }
 static extension-type-member method F4|constructor#_#new#tearOff<X extends asy::Future<core::num>>(self::F4|constructor#_#new#tearOff::X foo) → self::F4<self::F4|constructor#_#new#tearOff::X> /* = self::F4|constructor#_#new#tearOff::X */
  return self::F4|constructor#<self::F4|constructor#_#new#tearOff::X>(foo);
-static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* futureValueType= dynamic */ {
+static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* emittedValueType= dynamic */ {
  await invalid-expression "pkg/front_end/testcases/extension_types/issue53207.dart:21:9: Error: The 'await' expression can't be used for an expression with an extension type that is not a subtype of 'Future'.
  await e1; // Error.
        ^" in e1 /* runtimeCheckType= asy::Future<self::E1 /* = asy::Future<core::int> */> */ ;
--- a/pkg/front_end/testcases/extension_types/issue53207.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/issue53207.dart.weak.transformed.expect
@ -131,7 +131,7 @@ static extension-type-member method F4|constructor#<X extends asy::Future<core::
 }
 static extension-type-member method F4|constructor#_#new#tearOff<X extends asy::Future<core::num>>(self::F4|constructor#_#new#tearOff::X foo) → self::F4<self::F4|constructor#_#new#tearOff::X> /* = self::F4|constructor#_#new#tearOff::X */
  return self::F4|constructor#<self::F4|constructor#_#new#tearOff::X>(foo);
-static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* futureValueType= dynamic */ {
+static method test(self::E1 /* = asy::Future<core::int> */ e1, self::E2<asy::Future<core::String>> /* = asy::Future<core::String> */ e2, self::E3 /* = FutureOr<core::bool>*/ e3, self::E4<asy::Future<core::double>> /* = asy::Future<core::double> */ e4, self::E5<core::Object> /* = core::Object */ e5object, self::E5<asy::Future<core::num>> /* = asy::Future<core::num> */ e5future, self::F1 /* = asy::Future<core::int> */ f1, self::F2<asy::Future<core::num>> /* = asy::Future<core::num> */ f2, self::F3<asy::Future<core::String>> /* = asy::Future<core::String> */ f3, self::F4<asy::Future<core::int>> /* = asy::Future<core::int> */ f4) → dynamic async /* emittedValueType= dynamic */ {
  await invalid-expression "pkg/front_end/testcases/extension_types/issue53207.dart:21:9: Error: The 'await' expression can't be used for an expression with an extension type that is not a subtype of 'Future'.
  await e1; // Error.
        ^" in e1 /* runtimeCheckType= asy::Future<self::E1 /* = asy::Future<core::int> */> */ ;
--- a/pkg/front_end/testcases/extension_types/pattern_for_in.dart.strong.expect
+++ b/pkg/front_end/testcases/extension_types/pattern_for_in.dart.strong.expect
@ -27,13 +27,13 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 }
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
-static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  for (core::int a in list) {
  }
  await for (core::int a in stream) {
  }
 }
-static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  for (final(core::int, core::String) #t1 in list) {
    hoisted core::int a;
    hoisted core::String b;
--- a/pkg/front_end/testcases/extension_types/pattern_for_in.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/pattern_for_in.dart.strong.transformed.expect
@ -27,7 +27,7 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 }
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
-static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  {
    synthesized core::Iterator<core::int> :sync-for-iterator = list.{core::Iterable::iterator}{core::Iterator<core::int>};
    for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
@ -48,7 +48,7 @@ static method method1(self::MyList<core::int> /* = core::List<core::int> */ list
        await :for-iterator.{asy::_StreamIterator::cancel}(){() → asy::Future<dynamic>};
  }
 }
-static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  {
    synthesized core::Iterator<(core::int, core::String)> :sync-for-iterator = list.{core::Iterable::iterator}{core::Iterator<(core::int, core::String)>};
    for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
--- a/pkg/front_end/testcases/extension_types/pattern_for_in.dart.weak.expect
+++ b/pkg/front_end/testcases/extension_types/pattern_for_in.dart.weak.expect
@ -27,13 +27,13 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 }
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
-static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  for (core::int a in list) {
  }
  await for (core::int a in stream) {
  }
 }
-static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  for (final(core::int, core::String) #t1 in list) {
    hoisted core::int a;
    hoisted core::String b;
--- a/pkg/front_end/testcases/extension_types/pattern_for_in.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extension_types/pattern_for_in.dart.weak.modular.expect
@ -27,13 +27,13 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 }
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
-static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  for (core::int a in list) {
  }
  await for (core::int a in stream) {
  }
 }
-static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  for (final(core::int, core::String) #t1 in list) {
    hoisted core::int a;
    hoisted core::String b;
--- a/pkg/front_end/testcases/extension_types/pattern_for_in.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/pattern_for_in.dart.weak.transformed.expect
@ -27,7 +27,7 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 }
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
-static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method1(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::int> /* = asy::Stream<core::int> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  {
    synthesized core::Iterator<core::int> :sync-for-iterator = list.{core::Iterable::iterator}{core::Iterator<core::int>};
    for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
@ -48,7 +48,7 @@ static method method1(self::MyList<core::int> /* = core::List<core::int> */ list
        await :for-iterator.{asy::_StreamIterator::cancel}(){() → asy::Future<dynamic>};
  }
 }
-static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* futureValueType= dynamic */ {
+static method method2(self::MyList<(core::int, core::String)> /* = core::List<(core::int, core::String)> */ list, self::MyStream<(core::int, core::String)> /* = asy::Stream<(core::int, core::String)> */ stream) → dynamic async /* emittedValueType= dynamic */ {
  {
    synthesized core::Iterator<(core::int, core::String)> :sync-for-iterator = list.{core::Iterable::iterator}{core::Iterator<(core::int, core::String)>};
    for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
--- a/pkg/front_end/testcases/extension_types/yield.dart.strong.expect
+++ b/pkg/front_end/testcases/extension_types/yield.dart.strong.expect
@ -26,10 +26,10 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
 static method method(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::String> /* = asy::Stream<core::String> */ stream) → dynamic {
-  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* {
+  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
    yield* list;
  };
-  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* {
+  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
    yield* stream;
  };
 }
--- a/pkg/front_end/testcases/extension_types/yield.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/yield.dart.strong.transformed.expect
@ -26,10 +26,10 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
 static method method(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::String> /* = asy::Stream<core::String> */ stream) → dynamic {
-  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* {
+  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
    yield* list;
  };
-  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* {
+  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
    yield* stream;
  };
 }
--- a/pkg/front_end/testcases/extension_types/yield.dart.weak.expect
+++ b/pkg/front_end/testcases/extension_types/yield.dart.weak.expect
@ -26,10 +26,10 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
 static method method(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::String> /* = asy::Stream<core::String> */ stream) → dynamic {
-  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* {
+  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
    yield* list;
  };
-  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* {
+  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
    yield* stream;
  };
 }
--- a/pkg/front_end/testcases/extension_types/yield.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extension_types/yield.dart.weak.modular.expect
@ -26,10 +26,10 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
 static method method(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::String> /* = asy::Stream<core::String> */ stream) → dynamic {
-  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* {
+  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
    yield* list;
  };
-  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* {
+  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
    yield* stream;
  };
 }
--- a/pkg/front_end/testcases/extension_types/yield.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/yield.dart.weak.transformed.expect
@ -26,10 +26,10 @@ static extension-type-member method MyStream|constructor#<T extends core::Object
 static extension-type-member method MyStream|constructor#_#new#tearOff<T extends core::Object? = dynamic>(asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> it) → self::MyStream<self::MyStream|constructor#_#new#tearOff::T%> /* = asy::Stream<self::MyStream|constructor#_#new#tearOff::T%> */
  return self::MyStream|constructor#<self::MyStream|constructor#_#new#tearOff::T%>(it);
 static method method(self::MyList<core::int> /* = core::List<core::int> */ list, self::MyStream<core::String> /* = asy::Stream<core::String> */ stream) → dynamic {
-  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* {
+  () → core::Iterable<core::int> a = () → core::Iterable<core::int> sync* /* emittedValueType= core::int */ {
    yield* list;
  };
-  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* {
+  () → asy::Stream<core::String> b = () → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
    yield* stream;
  };
 }
--- a/pkg/front_end/testcases/extensions/async_extensions.dart.strong.expect
+++ b/pkg/front_end/testcases/extensions/async_extensions.dart.strong.expect
@ -10,13 +10,13 @@ extension Extension on core::int {
  method asyncStarMethod = self::Extension|asyncStarMethod;
  method tearoff asyncStarMethod = self::Extension|get#asyncStarMethod;
 }
-static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* {}
+static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#syncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|syncStarMethod(#this);
-static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* futureValueType= dynamic */ {}
+static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncMethod(#this);
-static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* {}
+static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncStarMethod(#this);
 static method main() → dynamic {
--- a/pkg/front_end/testcases/extensions/async_extensions.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extensions/async_extensions.dart.strong.transformed.expect
@ -10,13 +10,13 @@ extension Extension on core::int {
  method asyncStarMethod = self::Extension|asyncStarMethod;
  method tearoff asyncStarMethod = self::Extension|get#asyncStarMethod;
 }
-static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* {}
+static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#syncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|syncStarMethod(#this);
-static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* futureValueType= dynamic */ {}
+static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncMethod(#this);
-static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* {}
+static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncStarMethod(#this);
 static method main() → dynamic {
--- a/pkg/front_end/testcases/extensions/async_extensions.dart.weak.expect
+++ b/pkg/front_end/testcases/extensions/async_extensions.dart.weak.expect
@ -10,13 +10,13 @@ extension Extension on core::int {
  method asyncStarMethod = self::Extension|asyncStarMethod;
  method tearoff asyncStarMethod = self::Extension|get#asyncStarMethod;
 }
-static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* {}
+static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#syncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|syncStarMethod(#this);
-static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* futureValueType= dynamic */ {}
+static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncMethod(#this);
-static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* {}
+static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncStarMethod(#this);
 static method main() → dynamic {
--- a/pkg/front_end/testcases/extensions/async_extensions.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extensions/async_extensions.dart.weak.modular.expect
@ -10,13 +10,13 @@ extension Extension on core::int {
  method asyncStarMethod = self::Extension|asyncStarMethod;
  method tearoff asyncStarMethod = self::Extension|get#asyncStarMethod;
 }
-static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* {}
+static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#syncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|syncStarMethod(#this);
-static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* futureValueType= dynamic */ {}
+static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncMethod(#this);
-static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* {}
+static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncStarMethod(#this);
 static method main() → dynamic {
--- a/pkg/front_end/testcases/extensions/async_extensions.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extensions/async_extensions.dart.weak.transformed.expect
@ -10,13 +10,13 @@ extension Extension on core::int {
  method asyncStarMethod = self::Extension|asyncStarMethod;
  method tearoff asyncStarMethod = self::Extension|get#asyncStarMethod;
 }
-static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* {}
+static extension-member method Extension|syncStarMethod(lowered final core::int #this) → dynamic sync* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#syncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|syncStarMethod(#this);
-static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* futureValueType= dynamic */ {}
+static extension-member method Extension|asyncMethod(lowered final core::int #this) → dynamic async /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncMethod(#this);
-static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* {}
+static extension-member method Extension|asyncStarMethod(lowered final core::int #this) → dynamic async* /* emittedValueType= dynamic */ {}
 static extension-member method Extension|get#asyncStarMethod(lowered final core::int #this) → () → dynamic
  return () → dynamic => self::Extension|asyncStarMethod(#this);
 static method main() → dynamic {
--- a/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.strong.expect
+++ b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.strong.expect
@ -13,7 +13,7 @@ import "dart:core" as core;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::Extension|staticField);
  self::expect(0, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(0));
--- a/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.strong.transformed.expect
@ -13,7 +13,7 @@ import "deferred_explicit_access_lib.dart" as def;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final core::Object* #t1 = CheckLibraryIsLoaded(prefix) in def::Extension|staticField);
  self::expect(0, let final core::Object* #t2 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(0));
--- a/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.expect
+++ b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.expect
@ -13,7 +13,7 @@ import "dart:core" as core;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::Extension|staticField);
  self::expect(0, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(0));
--- a/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.modular.expect
@ -13,7 +13,7 @@ import "dart:core" as core;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::Extension|staticField);
  self::expect(0, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(0));
--- a/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.transformed.expect
@ -13,7 +13,7 @@ import "deferred_explicit_access_lib.dart" as def;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final core::Object* #t1 = CheckLibraryIsLoaded(prefix) in def::Extension|staticField);
  self::expect(0, let final core::Object* #t2 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(0));
--- a/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.strong.expect
+++ b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.strong.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix hide Extension;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
  self::expect(42, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::topLevelField = 42);
--- a/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.strong.transformed.expect
@ -5,7 +5,7 @@ import "deferred_explicit_access_lib.dart" as def;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix hide Extension;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final core::Object* #t1 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
  self::expect(42, let final core::Object* #t2 = CheckLibraryIsLoaded(prefix) in def::topLevelField = 42);
--- a/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.expect
+++ b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix hide Extension;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
  self::expect(42, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::topLevelField = 42);
--- a/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.modular.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix hide Extension;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
  self::expect(42, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::topLevelField = 42);
--- a/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.transformed.expect
@ -5,7 +5,7 @@ import "deferred_explicit_access_lib.dart" as def;

 import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix hide Extension;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await LoadLibrary(prefix);
  self::expect(0, let final core::Object* #t1 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
  self::expect(42, let final core::Object* #t2 = CheckLibraryIsLoaded(prefix) in def::topLevelField = 42);
--- a/pkg/front_end/testcases/general/async_function.dart.strong.expect
+++ b/pkg/front_end/testcases/general/async_function.dart.strong.expect
@ -6,28 +6,28 @@ import "dart:core" as core;
 import "dart:async";

 static field core::List<core::String> stringList = <core::String>["bar"];
-static method asyncString() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return "foo";
 }
-static method asyncString2() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString2() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return self::asyncString();
 }
-static method syncStarString() → core::Iterable<core::String> sync* {
+static method syncStarString() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::syncStarString2();
  yield* self::stringList;
 }
-static method syncStarString2() → core::Iterable<core::String> sync* {
+static method syncStarString2() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
 }
-static method asyncStarString() → asy::Stream<core::String> async* {
+static method asyncStarString() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::asyncStarString2();
  yield await self::asyncString();
 }
-static method asyncStarString2() → asy::Stream<core::String> async* {
+static method asyncStarString2() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "bar";
 }
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::String str = await self::asyncString();
 }
--- a/pkg/front_end/testcases/general/async_function.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/general/async_function.dart.strong.transformed.expect
@ -6,28 +6,28 @@ import "dart:core" as core;
 import "dart:async";

 static field core::List<core::String> stringList = core::_GrowableList::_literal1<core::String>("bar");
-static method asyncString() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return "foo";
 }
-static method asyncString2() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString2() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return self::asyncString();
 }
-static method syncStarString() → core::Iterable<core::String> sync* {
+static method syncStarString() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::syncStarString2();
  yield* self::stringList;
 }
-static method syncStarString2() → core::Iterable<core::String> sync* {
+static method syncStarString2() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
 }
-static method asyncStarString() → asy::Stream<core::String> async* {
+static method asyncStarString() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::asyncStarString2();
  yield await self::asyncString();
 }
-static method asyncStarString2() → asy::Stream<core::String> async* {
+static method asyncStarString2() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "bar";
 }
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::String str = await self::asyncString();
 }
--- a/pkg/front_end/testcases/general/async_function.dart.weak.expect
+++ b/pkg/front_end/testcases/general/async_function.dart.weak.expect
@ -6,28 +6,28 @@ import "dart:core" as core;
 import "dart:async";

 static field core::List<core::String> stringList = <core::String>["bar"];
-static method asyncString() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return "foo";
 }
-static method asyncString2() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString2() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return self::asyncString();
 }
-static method syncStarString() → core::Iterable<core::String> sync* {
+static method syncStarString() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::syncStarString2();
  yield* self::stringList;
 }
-static method syncStarString2() → core::Iterable<core::String> sync* {
+static method syncStarString2() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
 }
-static method asyncStarString() → asy::Stream<core::String> async* {
+static method asyncStarString() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::asyncStarString2();
  yield await self::asyncString();
 }
-static method asyncStarString2() → asy::Stream<core::String> async* {
+static method asyncStarString2() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "bar";
 }
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::String str = await self::asyncString();
 }
--- a/pkg/front_end/testcases/general/async_function.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/general/async_function.dart.weak.modular.expect
@ -6,28 +6,28 @@ import "dart:core" as core;
 import "dart:async";

 static field core::List<core::String> stringList = <core::String>["bar"];
-static method asyncString() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return "foo";
 }
-static method asyncString2() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString2() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return self::asyncString();
 }
-static method syncStarString() → core::Iterable<core::String> sync* {
+static method syncStarString() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::syncStarString2();
  yield* self::stringList;
 }
-static method syncStarString2() → core::Iterable<core::String> sync* {
+static method syncStarString2() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
 }
-static method asyncStarString() → asy::Stream<core::String> async* {
+static method asyncStarString() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::asyncStarString2();
  yield await self::asyncString();
 }
-static method asyncStarString2() → asy::Stream<core::String> async* {
+static method asyncStarString2() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "bar";
 }
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::String str = await self::asyncString();
 }
--- a/pkg/front_end/testcases/general/async_function.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/async_function.dart.weak.transformed.expect
@ -6,28 +6,28 @@ import "dart:core" as core;
 import "dart:async";

 static field core::List<core::String> stringList = core::_GrowableList::_literal1<core::String>("bar");
-static method asyncString() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return "foo";
 }
-static method asyncString2() → asy::Future<core::String> async /* futureValueType= core::String */ {
+static method asyncString2() → asy::Future<core::String> async /* emittedValueType= core::String */ {
  return self::asyncString();
 }
-static method syncStarString() → core::Iterable<core::String> sync* {
+static method syncStarString() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::syncStarString2();
  yield* self::stringList;
 }
-static method syncStarString2() → core::Iterable<core::String> sync* {
+static method syncStarString2() → core::Iterable<core::String> sync* /* emittedValueType= core::String */ {
  yield "foo";
 }
-static method asyncStarString() → asy::Stream<core::String> async* {
+static method asyncStarString() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "foo";
  yield* self::asyncStarString2();
  yield await self::asyncString();
 }
-static method asyncStarString2() → asy::Stream<core::String> async* {
+static method asyncStarString2() → asy::Stream<core::String> async* /* emittedValueType= core::String */ {
  yield "bar";
 }
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::String str = await self::asyncString();
 }
--- a/pkg/front_end/testcases/general/async_function_returns_future_or.dart.strong.expect
+++ b/pkg/front_end/testcases/general/async_function_returns_future_or.dart.strong.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "dart:async";

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await self::returnsString();
  await self::returnsFutureOrString();
  await self::returnsAwaitFutureOrString();
@ -17,27 +17,27 @@ static method main() → dynamic async /* futureValueType= dynamic */ {
  await self::returnsFutureObject();
  await self::returnsAwaitFutureObject() /* runtimeCheckType= asy::Future<core::Object> */ ;
 }
-static method returnsString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return "a";
-static method returnsFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFutureOr<core::String>("a");
-static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return await self::getFutureOr<core::String>("a") /* runtimeCheckType= asy::Future<core::String> */ ;
-static method returnsFutureString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFuture<core::String>("a");
-static method returnsAwaitFutureString() → FutureOr<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureString() → FutureOr<core::String> async /* emittedValueType= core::String */ 
  return await self::getFuture<core::String>("a");
-static method returnsObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return new core::Object::•();
-static method returnsFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFutureOr<core::Object>(new core::Object::•());
-static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFutureOr<core::Object>(new core::Object::•()) /* runtimeCheckType= asy::Future<core::Object> */ ;
-static method returnsFutureObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFuture<core::Object>(new core::Object::•());
-static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFuture<core::Object>(new core::Object::•());
-static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* futureValueType= self::getFutureOr::T% */ 
+static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* emittedValueType= self::getFutureOr::T% */ 
  return v;
-static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* futureValueType= self::getFuture::T% */ 
+static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* emittedValueType= self::getFuture::T% */ 
  return v;
--- a/pkg/front_end/testcases/general/async_function_returns_future_or.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/general/async_function_returns_future_or.dart.strong.transformed.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "dart:async";

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await self::returnsString();
  await self::returnsFutureOrString();
  await self::returnsAwaitFutureOrString();
@ -17,27 +17,27 @@ static method main() → dynamic async /* futureValueType= dynamic */ {
  await self::returnsFutureObject();
  await self::returnsAwaitFutureObject() /* runtimeCheckType= asy::Future<core::Object> */ ;
 }
-static method returnsString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return "a";
-static method returnsFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFutureOr<core::String>("a");
-static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return await self::getFutureOr<core::String>("a") /* runtimeCheckType= asy::Future<core::String> */ ;
-static method returnsFutureString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFuture<core::String>("a");
-static method returnsAwaitFutureString() → FutureOr<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureString() → FutureOr<core::String> async /* emittedValueType= core::String */ 
  return await self::getFuture<core::String>("a");
-static method returnsObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return new core::Object::•();
-static method returnsFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFutureOr<core::Object>(new core::Object::•());
-static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFutureOr<core::Object>(new core::Object::•()) /* runtimeCheckType= asy::Future<core::Object> */ ;
-static method returnsFutureObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFuture<core::Object>(new core::Object::•());
-static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFuture<core::Object>(new core::Object::•());
-static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* futureValueType= self::getFutureOr::T% */ 
+static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* emittedValueType= self::getFutureOr::T% */ 
  return v;
-static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* futureValueType= self::getFuture::T% */ 
+static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* emittedValueType= self::getFuture::T% */ 
  return v;
--- a/pkg/front_end/testcases/general/async_function_returns_future_or.dart.weak.expect
+++ b/pkg/front_end/testcases/general/async_function_returns_future_or.dart.weak.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "dart:async";

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await self::returnsString();
  await self::returnsFutureOrString();
  await self::returnsAwaitFutureOrString();
@ -17,27 +17,27 @@ static method main() → dynamic async /* futureValueType= dynamic */ {
  await self::returnsFutureObject();
  await self::returnsAwaitFutureObject() /* runtimeCheckType= asy::Future<core::Object> */ ;
 }
-static method returnsString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return "a";
-static method returnsFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFutureOr<core::String>("a");
-static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return await self::getFutureOr<core::String>("a") /* runtimeCheckType= asy::Future<core::String> */ ;
-static method returnsFutureString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFuture<core::String>("a");
-static method returnsAwaitFutureString() → FutureOr<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureString() → FutureOr<core::String> async /* emittedValueType= core::String */ 
  return await self::getFuture<core::String>("a");
-static method returnsObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return new core::Object::•();
-static method returnsFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFutureOr<core::Object>(new core::Object::•());
-static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFutureOr<core::Object>(new core::Object::•()) /* runtimeCheckType= asy::Future<core::Object> */ ;
-static method returnsFutureObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFuture<core::Object>(new core::Object::•());
-static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFuture<core::Object>(new core::Object::•());
-static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* futureValueType= self::getFutureOr::T% */ 
+static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* emittedValueType= self::getFutureOr::T% */ 
  return v;
-static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* futureValueType= self::getFuture::T% */ 
+static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* emittedValueType= self::getFuture::T% */ 
  return v;
--- a/pkg/front_end/testcases/general/async_function_returns_future_or.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/general/async_function_returns_future_or.dart.weak.modular.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "dart:async";

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await self::returnsString();
  await self::returnsFutureOrString();
  await self::returnsAwaitFutureOrString();
@ -17,27 +17,27 @@ static method main() → dynamic async /* futureValueType= dynamic */ {
  await self::returnsFutureObject();
  await self::returnsAwaitFutureObject() /* runtimeCheckType= asy::Future<core::Object> */ ;
 }
-static method returnsString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return "a";
-static method returnsFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFutureOr<core::String>("a");
-static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return await self::getFutureOr<core::String>("a") /* runtimeCheckType= asy::Future<core::String> */ ;
-static method returnsFutureString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFuture<core::String>("a");
-static method returnsAwaitFutureString() → FutureOr<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureString() → FutureOr<core::String> async /* emittedValueType= core::String */ 
  return await self::getFuture<core::String>("a");
-static method returnsObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return new core::Object::•();
-static method returnsFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFutureOr<core::Object>(new core::Object::•());
-static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFutureOr<core::Object>(new core::Object::•()) /* runtimeCheckType= asy::Future<core::Object> */ ;
-static method returnsFutureObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFuture<core::Object>(new core::Object::•());
-static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFuture<core::Object>(new core::Object::•());
-static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* futureValueType= self::getFutureOr::T% */ 
+static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* emittedValueType= self::getFutureOr::T% */ 
  return v;
-static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* futureValueType= self::getFuture::T% */ 
+static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* emittedValueType= self::getFuture::T% */ 
  return v;
--- a/pkg/front_end/testcases/general/async_function_returns_future_or.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/async_function_returns_future_or.dart.weak.transformed.expect
@ -5,7 +5,7 @@ import "dart:core" as core;

 import "dart:async";

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  await self::returnsString();
  await self::returnsFutureOrString();
  await self::returnsAwaitFutureOrString();
@ -17,27 +17,27 @@ static method main() → dynamic async /* futureValueType= dynamic */ {
  await self::returnsFutureObject();
  await self::returnsAwaitFutureObject() /* runtimeCheckType= asy::Future<core::Object> */ ;
 }
-static method returnsString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return "a";
-static method returnsFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFutureOr<core::String>("a");
-static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureOrString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return await self::getFutureOr<core::String>("a") /* runtimeCheckType= asy::Future<core::String> */ ;
-static method returnsFutureString() → asy::Future<core::String> async /* futureValueType= core::String */ 
+static method returnsFutureString() → asy::Future<core::String> async /* emittedValueType= core::String */ 
  return self::getFuture<core::String>("a");
-static method returnsAwaitFutureString() → FutureOr<core::String> async /* futureValueType= core::String */ 
+static method returnsAwaitFutureString() → FutureOr<core::String> async /* emittedValueType= core::String */ 
  return await self::getFuture<core::String>("a");
-static method returnsObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return new core::Object::•();
-static method returnsFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFutureOr<core::Object>(new core::Object::•());
-static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureOrObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFutureOr<core::Object>(new core::Object::•()) /* runtimeCheckType= asy::Future<core::Object> */ ;
-static method returnsFutureObject() → asy::Future<core::Object> async /* futureValueType= core::Object */ 
+static method returnsFutureObject() → asy::Future<core::Object> async /* emittedValueType= core::Object */ 
  return self::getFuture<core::Object>(new core::Object::•());
-static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* futureValueType= core::Object */ 
+static method returnsAwaitFutureObject() → FutureOr<core::Object> async /* emittedValueType= core::Object */ 
  return await self::getFuture<core::Object>(new core::Object::•());
-static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* futureValueType= self::getFutureOr::T% */ 
+static method getFutureOr<T extends core::Object? = dynamic>(self::getFutureOr::T% v) → FutureOr<self::getFutureOr::T%> async /* emittedValueType= self::getFutureOr::T% */ 
  return v;
-static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* futureValueType= self::getFuture::T% */ 
+static method getFuture<T extends core::Object? = dynamic>(self::getFuture::T% v) → asy::Future<self::getFuture::T%> async /* emittedValueType= self::getFuture::T% */ 
  return v;
--- a/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.strong.expect
+++ b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.strong.expect
@ -8,7 +8,7 @@ library;
 //
 import self as self;

-static method foo() → dynamic async /* futureValueType= dynamic */ {
+static method foo() → dynamic async /* emittedValueType= dynamic */ {
  invalid-type x;
  for (dynamic y in x{<invalid>}.z) {
  }
--- a/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.strong.transformed.expect
@ -8,7 +8,7 @@ library;
 //
 import self as self;

-static method foo() → dynamic async /* futureValueType= dynamic */ {
+static method foo() → dynamic async /* emittedValueType= dynamic */ {
  invalid-type x;
  invalid-expression "Invalid iterable type in for-in";
 }
--- a/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.expect
+++ b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.expect
@ -8,7 +8,7 @@ library;
 //
 import self as self;

-static method foo() → dynamic async /* futureValueType= dynamic */ {
+static method foo() → dynamic async /* emittedValueType= dynamic */ {
  invalid-type x;
  for (dynamic y in x{<invalid>}.z) {
  }
--- a/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.modular.expect
@ -8,7 +8,7 @@ library;
 //
 import self as self;

-static method foo() → dynamic async /* futureValueType= dynamic */ {
+static method foo() → dynamic async /* emittedValueType= dynamic */ {
  invalid-type x;
  for (dynamic y in x{<invalid>}.z) {
  }
--- a/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.transformed.expect
@ -8,7 +8,7 @@ library;
 //
 import self as self;

-static method foo() → dynamic async /* futureValueType= dynamic */ {
+static method foo() → dynamic async /* emittedValueType= dynamic */ {
  invalid-type x;
  invalid-expression "Invalid iterable type in for-in";
 }
--- a/pkg/front_end/testcases/general/async_nested.dart.strong.expect
+++ b/pkg/front_end/testcases/general/async_nested.dart.strong.expect
@ -17,7 +17,7 @@ class Node extends core::Object {
    return "${this.{self::Node::name}{core::String}} ${let final core::Iterable<dynamic>? #t3 = tmp in #t3 == null ?{core::String?} null : #t3{core::Iterable<dynamic>}.{core::Iterable::join}(" "){([core::String]) → core::String}}".{core::String::trim}(){() → core::String};
  }
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  core::String expected = "1 2 3 4 5 6 7 8 9 10";
  self::Node node = new self::Node::•("1", <self::Node>[new self::Node::•("2", <self::Node>[]), await asy::Future::value<self::Node>(new self::Node::•("3", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("4", <self::Node>[new self::Node::•("5", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("6", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("7", <self::Node>[]))])), await asy::Future::value<self::Node>(new self::Node::•("8", <self::Node>[])), await asy::Future::value<self::Node>(new self::Node::•("9", <self::Node>[]))])]))])), await asy::Future::value<self::Node>(new self::Node::•("10", <self::Node>[]))]);
  core::String actual = node.{self::Node::toSimpleString}(){() → dynamic} as{TypeError,ForDynamic} core::String;
--- a/pkg/front_end/testcases/general/async_nested.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/general/async_nested.dart.strong.transformed.expect
@ -17,7 +17,7 @@ class Node extends core::Object {
    return "${this.{self::Node::name}{core::String}} ${let final core::Iterable<dynamic>? #t3 = tmp in #t3 == null ?{core::String?} null : #t3{core::Iterable<dynamic>}.{core::Iterable::join}(" "){([core::String]) → core::String}}".{core::String::trim}(){() → core::String};
  }
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  core::String expected = "1 2 3 4 5 6 7 8 9 10";
  self::Node node = new self::Node::•("1", core::_GrowableList::_literal3<self::Node>(new self::Node::•("2", core::_GrowableList::•<self::Node>(0)), await asy::Future::value<self::Node>(new self::Node::•("3", core::_GrowableList::_literal1<self::Node>(await asy::Future::value<self::Node>(new self::Node::•("4", core::_GrowableList::_literal1<self::Node>(new self::Node::•("5", core::_GrowableList::_literal3<self::Node>(await asy::Future::value<self::Node>(new self::Node::•("6", core::_GrowableList::_literal1<self::Node>(await asy::Future::value<self::Node>(new self::Node::•("7", core::_GrowableList::•<self::Node>(0)))))), await asy::Future::value<self::Node>(new self::Node::•("8", core::_GrowableList::•<self::Node>(0))), await asy::Future::value<self::Node>(new self::Node::•("9", core::_GrowableList::•<self::Node>(0))))))))))), await asy::Future::value<self::Node>(new self::Node::•("10", core::_GrowableList::•<self::Node>(0)))));
  core::String actual = node.{self::Node::toSimpleString}(){() → dynamic} as{TypeError,ForDynamic} core::String;
--- a/pkg/front_end/testcases/general/async_nested.dart.weak.expect
+++ b/pkg/front_end/testcases/general/async_nested.dart.weak.expect
@ -17,7 +17,7 @@ class Node extends core::Object {
    return "${this.{self::Node::name}{core::String}} ${let final core::Iterable<dynamic>? #t3 = tmp in #t3 == null ?{core::String?} null : #t3{core::Iterable<dynamic>}.{core::Iterable::join}(" "){([core::String]) → core::String}}".{core::String::trim}(){() → core::String};
  }
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  core::String expected = "1 2 3 4 5 6 7 8 9 10";
  self::Node node = new self::Node::•("1", <self::Node>[new self::Node::•("2", <self::Node>[]), await asy::Future::value<self::Node>(new self::Node::•("3", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("4", <self::Node>[new self::Node::•("5", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("6", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("7", <self::Node>[]))])), await asy::Future::value<self::Node>(new self::Node::•("8", <self::Node>[])), await asy::Future::value<self::Node>(new self::Node::•("9", <self::Node>[]))])]))])), await asy::Future::value<self::Node>(new self::Node::•("10", <self::Node>[]))]);
  core::String actual = node.{self::Node::toSimpleString}(){() → dynamic} as{TypeError,ForDynamic} core::String;
--- a/pkg/front_end/testcases/general/async_nested.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/general/async_nested.dart.weak.modular.expect
@ -17,7 +17,7 @@ class Node extends core::Object {
    return "${this.{self::Node::name}{core::String}} ${let final core::Iterable<dynamic>? #t3 = tmp in #t3 == null ?{core::String?} null : #t3{core::Iterable<dynamic>}.{core::Iterable::join}(" "){([core::String]) → core::String}}".{core::String::trim}(){() → core::String};
  }
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  core::String expected = "1 2 3 4 5 6 7 8 9 10";
  self::Node node = new self::Node::•("1", <self::Node>[new self::Node::•("2", <self::Node>[]), await asy::Future::value<self::Node>(new self::Node::•("3", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("4", <self::Node>[new self::Node::•("5", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("6", <self::Node>[await asy::Future::value<self::Node>(new self::Node::•("7", <self::Node>[]))])), await asy::Future::value<self::Node>(new self::Node::•("8", <self::Node>[])), await asy::Future::value<self::Node>(new self::Node::•("9", <self::Node>[]))])]))])), await asy::Future::value<self::Node>(new self::Node::•("10", <self::Node>[]))]);
  core::String actual = node.{self::Node::toSimpleString}(){() → dynamic} as{TypeError,ForDynamic} core::String;
--- a/pkg/front_end/testcases/general/async_nested.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/async_nested.dart.weak.transformed.expect
@ -17,7 +17,7 @@ class Node extends core::Object {
    return "${this.{self::Node::name}{core::String}} ${let final core::Iterable<dynamic>? #t3 = tmp in #t3 == null ?{core::String?} null : #t3{core::Iterable<dynamic>}.{core::Iterable::join}(" "){([core::String]) → core::String}}".{core::String::trim}(){() → core::String};
  }
 }
-static method main() → void async /* futureValueType= void */ {
+static method main() → void async /* emittedValueType= void */ {
  core::String expected = "1 2 3 4 5 6 7 8 9 10";
  self::Node node = new self::Node::•("1", core::_GrowableList::_literal3<self::Node>(new self::Node::•("2", core::_GrowableList::•<self::Node>(0)), await asy::Future::value<self::Node>(new self::Node::•("3", core::_GrowableList::_literal1<self::Node>(await asy::Future::value<self::Node>(new self::Node::•("4", core::_GrowableList::_literal1<self::Node>(new self::Node::•("5", core::_GrowableList::_literal3<self::Node>(await asy::Future::value<self::Node>(new self::Node::•("6", core::_GrowableList::_literal1<self::Node>(await asy::Future::value<self::Node>(new self::Node::•("7", core::_GrowableList::•<self::Node>(0)))))), await asy::Future::value<self::Node>(new self::Node::•("8", core::_GrowableList::•<self::Node>(0))), await asy::Future::value<self::Node>(new self::Node::•("9", core::_GrowableList::•<self::Node>(0))))))))))), await asy::Future::value<self::Node>(new self::Node::•("10", core::_GrowableList::•<self::Node>(0)))));
  core::String actual = node.{self::Node::toSimpleString}(){() → dynamic} as{TypeError,ForDynamic} core::String;
--- a/pkg/front_end/testcases/general/await.dart.strong.expect
+++ b/pkg/front_end/testcases/general/await.dart.strong.expect
@ -2,6 +2,6 @@ library;
 import self as self;
 import "dart:core" as core;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::print(await "Hello, World!" /* runtimeCheckType= dart.async::Future<core::String> */ );
 }
--- a/pkg/front_end/testcases/general/await.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/general/await.dart.strong.transformed.expect
@ -2,6 +2,6 @@ library;
 import self as self;
 import "dart:core" as core;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::print(await "Hello, World!" /* runtimeCheckType= dart.async::Future<core::String> */ );
 }
--- a/pkg/front_end/testcases/general/await.dart.weak.expect
+++ b/pkg/front_end/testcases/general/await.dart.weak.expect
@ -2,6 +2,6 @@ library;
 import self as self;
 import "dart:core" as core;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::print(await "Hello, World!" /* runtimeCheckType= dart.async::Future<core::String> */ );
 }
--- a/pkg/front_end/testcases/general/await.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/general/await.dart.weak.modular.expect
@ -2,6 +2,6 @@ library;
 import self as self;
 import "dart:core" as core;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::print(await "Hello, World!" /* runtimeCheckType= dart.async::Future<core::String> */ );
 }
--- a/pkg/front_end/testcases/general/await.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/await.dart.weak.transformed.expect
@ -2,6 +2,6 @@ library;
 import self as self;
 import "dart:core" as core;

-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  core::print(await "Hello, World!" /* runtimeCheckType= dart.async::Future<core::String> */ );
 }
--- a/pkg/front_end/testcases/general/await_complex.dart.strong.expect
+++ b/pkg/front_end/testcases/general/await_complex.dart.strong.expect
@ -52,7 +52,7 @@ static set topLevelSetter(dynamic val) → void {
 }
 static method dummy() → dynamic
  return 1;
-static method staticMembers() → dynamic async /* futureValueType= dynamic */ {
+static method staticMembers() → dynamic async /* emittedValueType= dynamic */ {
  core::num a = self::C::staticField.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(2, a);
  core::num f = (self::C::staticField = 1).{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
@ -66,7 +66,7 @@ static method staticMembers() → dynamic async /* futureValueType= dynamic */ {
  core::num e = self::C::staticField.{core::num::+}(self::C::staticGetter){(core::num) → core::int}.{core::num::+}(self::C::staticSetter = 1){(core::num) → core::int}.{core::num::+}(self::C::staticFoo(1)){(core::num) → core::int}.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(5, e);
 }
-static method topLevelMembers() → dynamic async /* futureValueType= dynamic */ {
+static method topLevelMembers() → dynamic async /* emittedValueType= dynamic */ {
  core::num a = self::globalVariable.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(2, a);
  core::num b = self::topLevelGetter.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
@ -78,7 +78,7 @@ static method topLevelMembers() → dynamic async /* futureValueType= dynamic */
  core::num e = self::globalVariable.{core::num::+}(self::topLevelGetter){(core::num) → core::int}.{core::num::+}(self::topLevelSetter = 1){(core::num) → core::int}.{core::num::+}(self::topLevelFoo(1)){(core::num) → core::int}.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(5, e);
 }
-static method instanceMembers() → dynamic async /* futureValueType= dynamic */ {
+static method instanceMembers() → dynamic async /* emittedValueType= dynamic */ {
  self::C inst = new self::C::•();
  core::num a = inst.{self::C::field}{core::int}.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(2, a);
@ -91,7 +91,7 @@ static method instanceMembers() → dynamic async /* futureValueType= dynamic */
  core::num e = inst.{self::C::field}{core::int}.{core::num::+}(inst.{self::C::getter}{core::int}){(core::num) → core::int}.{core::num::+}(inst.{self::C::setter} = 1){(core::num) → core::int}.{core::num::+}(inst.{self::C::foo}(1){(core::int) → core::int}){(core::num) → core::int}.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(5, e);
 }
-static method others() → dynamic async /* futureValueType= dynamic */ {
+static method others() → dynamic async /* emittedValueType= dynamic */ {
  core::String a = "${self::globalVariable} ${await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ } ".{core::String::+}(await "someString" /* runtimeCheckType= asy::Future<core::String> */ ){(core::String) → core::String};
  self::expect("1 1 someString", a);
  self::C c = new self::C::•();
@ -103,7 +103,7 @@ static method others() → dynamic async /* futureValueType= dynamic */ {
  core::num e = b.{core::List::[]}(0){(core::int) → core::int}.{core::num::+}(await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::num){(core::num) → core::num};
  self::expect(2, e);
 }
-static method conditionals() → dynamic async /* futureValueType= dynamic */ {
+static method conditionals() → dynamic async /* emittedValueType= dynamic */ {
  core::bool a = false;
  core::bool b = true;
  core::bool c = a || b || await self::dummy() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic} core::bool;
@ -118,7 +118,7 @@ static method conditionals() → dynamic async /* futureValueType= dynamic */ {
  on core::Object catch(final core::Object e) {
  }
 }
-static method asserts() → dynamic async /* futureValueType= dynamic */ {
+static method asserts() → dynamic async /* emittedValueType= dynamic */ {
  for (final <T extends core::Object? = dynamic>(T%) → FutureOr<T%>func in <<T extends core::Object? = dynamic>(T%) → FutureOr<T%>>[#C1, #C2]) {
    assert(await func<core::bool>(true){(core::bool) → FutureOr<core::bool>} /* runtimeCheckType= asy::Future<core::bool> */ );
    assert(invalid-expression "pkg/front_end/testcases/general/await_complex.dart:120:12: Error: A value of type 'FutureOr<bool>' can't be assigned to a variable of type 'bool'.
@ -135,7 +135,7 @@ static method asserts() → dynamic async /* futureValueType= dynamic */ {
    }
  }
 }
-static method controlFlow() → dynamic async /* futureValueType= dynamic */ {
+static method controlFlow() → dynamic async /* emittedValueType= dynamic */ {
  for (final <T extends core::Object? = dynamic>(T%) → FutureOr<T%>func in <<T extends core::Object? = dynamic>(T%) → FutureOr<T%>>[#C1, #C2]) {
    core::int c = 0;
    for (core::int i = await func<core::int>(0){(core::int) → FutureOr<core::int>} /* runtimeCheckType= asy::Future<core::int> */ ; await func<core::bool>(i.{core::num::<}(5){(core::num) → core::bool}){(core::bool) → FutureOr<core::bool>} /* runtimeCheckType= asy::Future<core::bool> */ ; await func<core::int>(let final core::int #t1 = i in let final core::int #t2 = i = #t1.{core::num::+}(1){(core::num) → core::int} in #t1){(core::int) → FutureOr<core::int>} /* runtimeCheckType= asy::Future<core::int> */ ) {
@ -203,30 +203,30 @@ static method controlFlow() → dynamic async /* futureValueType= dynamic */ {
          throw "unreachable";
        }
    }
-    self::expect(42, await(() → asy::Future<core::int> async /* futureValueType= core::int */ {
+    self::expect(42, await(() → asy::Future<core::int> async /* emittedValueType= core::int */ {
      return await func<core::int>(42){(core::int) → FutureOr<core::int>} /* runtimeCheckType= asy::Future<core::int> */ ;
    })(){() → asy::Future<core::int>});
-    self::expect(42, await(() → asy::Future<core::int> async /* futureValueType= core::int */ {
+    self::expect(42, await(() → asy::Future<core::int> async /* emittedValueType= core::int */ {
      return func<core::int>(42){(core::int) → FutureOr<core::int>};
    })(){() → asy::Future<core::int>});
-    function testStream1() → asy::Stream<core::int> async* {
+    function testStream1() → asy::Stream<core::int> async* /* emittedValueType= core::int */ {
      yield await func<core::int>(42){(core::int) → FutureOr<core::int>} /* runtimeCheckType= asy::Future<core::int> */ ;
    }
    self::expectList(<dynamic>[42], await testStream1(){() → asy::Stream<core::int>}.{asy::Stream::toList}(){() → asy::Future<core::List<core::int>>});
-    function testStream2() → asy::Stream<core::int> async* {
+    function testStream2() → asy::Stream<core::int> async* /* emittedValueType= core::int */ {
      yield* await func<asy::Stream<core::int>>(self::intStream()){(asy::Stream<core::int>) → FutureOr<asy::Stream<core::int>>} /* runtimeCheckType= asy::Future<asy::Stream<core::int>> */ ;
    }
    self::expectList(<dynamic>[42], await testStream2(){() → asy::Stream<core::int>}.{asy::Stream::toList}(){() → asy::Future<core::List<core::int>>});
  }
 }
-static method future<T extends core::Object? = dynamic>(self::future::T% value) → FutureOr<self::future::T%> async /* futureValueType= self::future::T% */ 
+static method future<T extends core::Object? = dynamic>(self::future::T% value) → FutureOr<self::future::T%> async /* emittedValueType= self::future::T% */ 
  return value;
 static method id<T extends core::Object? = dynamic>(self::id::T% value) → FutureOr<self::id::T%>
  return value;
-static method intStream() → asy::Stream<core::int> async* {
+static method intStream() → asy::Stream<core::int> async* /* emittedValueType= core::int */ {
  yield 42;
 }
-static method main() → dynamic async /* futureValueType= dynamic */ {
+static method main() → dynamic async /* emittedValueType= dynamic */ {
  for (core::int i = 0; i.{core::num::<}(11){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
    await self::staticMembers() /* runtimeCheckType= asy::Future<dynamic> */ ;
    await self::topLevelMembers() /* runtimeCheckType= asy::Future<dynamic> */ ;
--- a/Show more
+++ b/Show more