[dart2j] Add TypeEnvironmentStructure and TypeRecipe

These will be tracked through SSA to generate correct recipe strings.

Change-Id: Ifebeead0f39d87be3208c673e34793145c64cf23
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/106181
Reviewed-by: Mayank Patke <[email protected]>
Commit-Queue: Stephen Adams <[email protected]>

Author: rakudrama

pkg/compiler/lib/src/js_model/type_recipe.dart

@@ -0,0 +1,85 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library dart2js.js_model.type_recipe;
+
+import '../elements/types.dart';
+
+/// A TypeEnvironmentStructure describes the shape or layout of a reified type
+/// environment.
+///
+/// A type environment maps type parameter variables to type values. The type
+/// variables are mostly elided in the runtime representation, replaced by
+/// indexes into the reified environment.
+abstract class TypeEnvironmentStructure {}
+
+/// A singleton type environment maps a binds a single value.
+class SingletonTypeEnvironmentStructure extends TypeEnvironmentStructure {
+  final TypeVariableType variable;
+
+  SingletonTypeEnvironmentStructure(this.variable);
+
+  @override
+  String toString() => 'SingletonTypeEnvironmentStructure($variable)';
+}
+
+/// A type environment containing an interface type and/or a tuple of function
+/// type parameters.
+class FullTypeEnvironmentStructure extends TypeEnvironmentStructure {
+  final InterfaceType classType;
+  final List<TypeVariableType> bindings;
+
+  FullTypeEnvironmentStructure({this.classType, this.bindings = const []});
+
+  @override
+  String toString() => 'FullTypeEnvironmentStructure($classType, $bindings)';
+}
+
+/// A TypeRecipe is evaluated against a type environment to produce either a
+/// type, or another type environment.
+abstract class TypeRecipe {}
+
+/// A recipe that yields a reified type.
+class TypeExpressionRecipe extends TypeRecipe {
+  final DartType type;
+
+  TypeExpressionRecipe(this.type);
+
+  @override
+  String toString() => 'TypeExpressionRecipe($type)';
+}
+
+/// A recipe that yields a reified type environment.
+abstract class TypeEnvironmentRecipe extends TypeRecipe {}
+
+/// A recipe that yields a reified type environment that binds a single generic
+/// function type parameter.
+class SingletonTypeEnvironmentRecipe extends TypeEnvironmentRecipe {
+  final DartType type;
+
+  SingletonTypeEnvironmentRecipe(this.type);
+
+  @override
+  String toString() => 'SingletonTypeEnvironmentRecipe($type)';
+}
+
+/// A recipe that yields a reified type environment that binds a class instance
+/// type and/or a tuple of types, usually generic function type arguments.
+///
+/// With no class is also used as a tuple of types.
+class FullTypeEnvironmentRecipe extends TypeEnvironmentRecipe {
+  /// Type expression for the interface type of a class scope.  `null` for
+  /// environments outside a class scope or a class scope where no supertype is
+  /// generic, or where optimization has determined that no use of the
+  /// environment requires any of the class type variables.
+  final InterfaceType classType;
+
+  // Type expressions for the tuple of function type arguments.
+  final List<DartType> types;
+
+  FullTypeEnvironmentRecipe({this.classType, this.types = const []});
+
+  @override
+  String toString() => 'FullTypeEnvironmentRecipe($classType, $types)';
+}

pkg/compiler/lib/src/ssa/codegen.dart

@@ -3333,31 +3333,31 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
 
   @override
   visitIsTest(HIsTest node) {
-    throw UnimplementedError('SsaCodeGenerator.visitIsTest');
+    throw UnimplementedError('SsaCodeGenerator.visitIsTest  $node');
   }
 
   @override
   visitAsCheck(HAsCheck node) {
-    throw UnimplementedError('SsaCodeGenerator.visitAsCheck');
+    throw UnimplementedError('SsaCodeGenerator.visitAsCheck  $node');
   }
 
   @override
   visitSubtypeCheck(HSubtypeCheck node) {
-    throw UnimplementedError('SsaCodeGenerator.visitSubtypeCheck');
+    throw UnimplementedError('SsaCodeGenerator.visitSubtypeCheck  $node');
   }
 
   @override
   visitLoadType(HLoadType node) {
-    throw UnimplementedError('SsaCodeGenerator.visitLoadType');
+    throw UnimplementedError('SsaCodeGenerator.visitLoadType  $node');
   }
 
   @override
   visitTypeEval(HTypeEval node) {
-    throw UnimplementedError('SsaCodeGenerator.visitTypeEval');
+    throw UnimplementedError('SsaCodeGenerator.visitTypeEval  $node');
   }
 
   @override
   visitTypeBind(HTypeBind node) {
-    throw UnimplementedError('SsaCodeGenerator.visitTypeBind');
+    throw UnimplementedError('SsaCodeGenerator.visitTypeBind  $node');
   }
 }

pkg/compiler/lib/src/ssa/nodes.dart

@@ -14,6 +14,7 @@ import '../elements/types.dart';
 import '../inferrer/abstract_value_domain.dart';
 import '../io/source_information.dart';
 import '../js/js.dart' as js;
+import '../js_model/type_recipe.dart' show TypeEnvironmentStructure, TypeRecipe;
 import '../native/behavior.dart';
 import '../universe/selector.dart' show Selector;
 import '../universe/side_effects.dart' show SideEffects;
@@ -4462,9 +4463,11 @@ class HLoadType extends HRtiInstruction {
 
 /// Evaluates an Rti type recipe in an Rti environment.
 class HTypeEval extends HRtiInstruction {
-  DartType typeExpression; // TODO(sra); Allow a type environment expression.
+  TypeEnvironmentStructure envStructure;
+  TypeRecipe typeExpression;
 
-  HTypeEval(HInstruction environment, this.typeExpression, AbstractValue type)
+  HTypeEval(HInstruction environment, this.envStructure, this.typeExpression,
+      AbstractValue type)
       : super([environment], type) {
     setUseGvn();
   }

pkg/compiler/lib/src/ssa/type_builder.dart

@@ -7,6 +7,7 @@ import 'nodes.dart';
 import '../elements/entities.dart';
 import '../elements/types.dart';
 import '../inferrer/abstract_value_domain.dart';
+import '../js_model/type_recipe.dart';
 import '../io/source_information.dart';
 import '../universe/use.dart' show TypeUse;
 import '../world.dart';
@@ -282,9 +283,11 @@ abstract class TypeBuilder {
       // TODO(sra): Locate type environment.
       HInstruction environment =
           builder.graph.addConstantString("env", _closedWorld);
-      HInstruction rti =
-          HTypeEval(environment, argument, _abstractValueDomain.dynamicType)
-            ..sourceInformation = sourceInformation;
+      // TODO(sra): Determine environment structure from context.
+      TypeEnvironmentStructure structure = null;
+      HInstruction rti = HTypeEval(environment, structure,
+          TypeExpressionRecipe(argument), _abstractValueDomain.dynamicType)
+        ..sourceInformation = sourceInformation;
       builder.add(rti);
       return rti;
     }