Support serialization of the compiler backbone.

pkg/compiler/lib/src/serialization/constant_serialization.dart

Index: pkg/compiler/lib/src/serialization/constant_serialization.dart
diff --git a/pkg/compiler/lib/src/serialization/constant_serialization.dart b/pkg/compiler/lib/src/serialization/constant_serialization.dart
new file mode 100644
index 0000000000000000000000000000000000000000..94dc24f2493babe05ce0af84c0345866ef06b198
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+++ b/pkg/compiler/lib/src/serialization/constant_serialization.dart
@@ -0,0 +1,430 @@
+// Copyright (c) 2015, 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.serialization.constants;
+
+import '../constants/expressions.dart';
+import '../dart_types.dart';
+import '../elements/elements.dart' show FieldElement;
+import '../resolution/operators.dart';
+import '../universe/universe.dart';
+import 'serialization.dart';
+import 'keys.dart';
+
+/// Visitor that serializes a [ConstantExpression] by encoding it into an
+/// [ObjectEncoder].
+///
+/// This class is called from the [Serializer] when a [ConstantExpression] needs
+/// serialization. The [ObjectEncoder] ensures that any [Element], [DartType],
+/// and other [ConstantExpression] that the serialized [ConstantExpression]
+/// depends upon are also serialized.
+class ConstantSerializer
+    extends ConstantExpressionVisitor<dynamic, ObjectEncoder> {
+  const ConstantSerializer();
+
+  @override
+  void visitBinary(BinaryConstantExpression exp,
+                   ObjectEncoder encoder) {
+    encoder.setEnum(Key.OPERATOR, exp.operator.kind);
+    encoder.setConstant(Key.LEFT, exp.left);
+    encoder.setConstant(Key.RIGHT, exp.right);
+  }
+
+  @override
+  void visitConcatenate(ConcatenateConstantExpression exp,
+                        ObjectEncoder encoder) {
+    encoder.setConstants(Key.ARGUMENTS, exp.expressions);
+  }
+
+  @override
+  void visitConditional(ConditionalConstantExpression exp,
+                        ObjectEncoder encoder) {
+    encoder.setConstant(Key.CONDITION, exp.condition);
+    encoder.setConstant(Key.TRUE, exp.trueExp);
+    encoder.setConstant(Key.FALSE, exp.falseExp);
+  }
+
+  @override
+  void visitConstructed(ConstructedConstantExpression exp,
+                        ObjectEncoder encoder) {
+    encoder.setElement(Key.ELEMENT, exp.target);
+    encoder.setType(Key.TYPE, exp.type);
+    encoder.setStrings(Key.NAMES, exp.callStructure.namedArguments);
+    encoder.setConstants(Key.ARGUMENTS, exp.arguments);
+  }
+
+  @override
+  void visitFunction(FunctionConstantExpression exp,
+                     ObjectEncoder encoder) {
+    encoder.setElement(Key.ELEMENT, exp.element);
+  }
+
+  @override
+  void visitIdentical(IdenticalConstantExpression exp,
+                      ObjectEncoder encoder) {
+    encoder.setConstant(Key.LEFT, exp.left);
+    encoder.setConstant(Key.RIGHT, exp.right);
+  }
+
+  @override
+  void visitList(ListConstantExpression exp, ObjectEncoder encoder) {
+    encoder.setType(Key.TYPE, exp.type);
+    encoder.setConstants(Key.VALUES, exp.values);
+  }
+
+  @override
+  void visitMap(MapConstantExpression exp, ObjectEncoder encoder) {
+    encoder.setType(Key.TYPE, exp.type);
+    encoder.setConstants(Key.KEYS, exp.keys);
+    encoder.setConstants(Key.VALUES, exp.values);
+  }
+
+  @override
+  void visitBool(BoolConstantExpression exp, ObjectEncoder encoder) {
+    encoder.setBool(Key.VALUE, exp.primitiveValue);
+  }
+
+  @override
+  void visitInt(IntConstantExpression exp, ObjectEncoder encoder) {
+    encoder.setInt(Key.VALUE, exp.primitiveValue);
+  }
+
+  @override
+  void visitDouble(DoubleConstantExpression exp, ObjectEncoder encoder) {
+    encoder.setDouble(Key.VALUE, exp.primitiveValue);
+  }
+
+  @override
+  void visitString(StringConstantExpression exp, ObjectEncoder encoder) {
+    encoder.setString(Key.VALUE, exp.primitiveValue);
+  }
+
+  @override
+  void visitNull(NullConstantExpression exp, ObjectEncoder encoder) {
+    // No additional data needed.
+  }
+
+  @override
+  void visitSymbol(SymbolConstantExpression exp,
+                   ObjectEncoder encoder) {
+    throw new UnsupportedError(
+        "ConstantSerializer.visitSymbol: ${exp.getText()}");
+  }
+
+  @override
+  void visitType(TypeConstantExpression exp,
+                 ObjectEncoder encoder) {
+    encoder.setType(Key.TYPE, exp.type);
+  }
+
+  @override
+  void visitUnary(UnaryConstantExpression exp,
+                  ObjectEncoder encoder) {
+    encoder.setEnum(Key.OPERATOR, exp.operator.kind);
+    encoder.setConstant(Key.EXPRESSION, exp.expression);
+  }
+
+  @override
+  void visitVariable(VariableConstantExpression exp,
+                     ObjectEncoder encoder) {
+    encoder.setElement(Key.ELEMENT, exp.element);
+  }
+
+  @override
+  void visitPositional(PositionalArgumentReference exp,
+                       ObjectEncoder encoder) {
+    encoder.setInt(Key.INDEX, exp.index);
+  }
+
+  @override
+  void visitNamed(NamedArgumentReference exp, ObjectEncoder encoder) {
+    encoder.setString(Key.NAME, exp.name);
+  }
+
+  @override
+  void visitBoolFromEnvironment(BoolFromEnvironmentConstantExpression exp,
+                                ObjectEncoder encoder) {
+    encoder.setConstant(Key.NAME, exp.name);
+    if (exp.defaultValue != null) {
+      encoder.setConstant(Key.DEFAULT, exp.defaultValue);
+    }
+  }
+
+  @override
+  void visitIntFromEnvironment(IntFromEnvironmentConstantExpression exp,
+                               ObjectEncoder encoder) {
+    encoder.setConstant(Key.NAME, exp.name);
+    if (exp.defaultValue != null) {
+      encoder.setConstant(Key.DEFAULT, exp.defaultValue);
+    }
+  }
+
+  @override
+  void visitStringFromEnvironment(StringFromEnvironmentConstantExpression exp,
+                                  ObjectEncoder encoder) {
+    encoder.setConstant(Key.NAME, exp.name);
+    if (exp.defaultValue != null) {
+      encoder.setConstant(Key.DEFAULT, exp.defaultValue);
+    }
+  }
+
+  @override
+  void visitStringLength(StringLengthConstantExpression exp,
+                         ObjectEncoder encoder) {
+    encoder.setConstant(Key.EXPRESSION, exp.expression);
+  }
+
+
+  @override
+  void visitDeferred(DeferredConstantExpression exp,
+                     ObjectEncoder encoder) {
+    throw new UnsupportedError(
+        "ConstantSerializer.visitDeferred: ${exp.getText()}");
+  }
+}
+
+/// Utility class for deserializing [ConstantExpression]s.
+///
+/// This is used by the [Deserializer].
+class ConstantDeserializer {
+
+  /// Deserializes a [ConstantExpression] from an [ObjectDecoder].
+  ///
+  /// The class is called from the [Deserializer] when a [ConstantExpression]
+  /// needs deserialization. The [ObjectDecoder] ensures that any [Element],
+  /// [DartType], and other [ConstantExpression] that the deserialized
+  /// [ConstantExpression] depends upon are available.
+  static ConstantExpression deserialize(ObjectDecoder decoder) {
+    ConstantExpressionKind kind =
+        decoder.getEnum(Key.KIND, ConstantExpressionKind.values);
+    switch (kind) {
+      case ConstantExpressionKind.BINARY:
+        BinaryOperator operator = BinaryOperator.fromKind(decoder.getEnum(
+            Key.OPERATOR, BinaryOperatorKind.values));
+        return new BinaryConstantExpression(
+            decoder.getConstant(Key.LEFT),
+            operator,
+            decoder.getConstant(Key.RIGHT));
+      case ConstantExpressionKind.BOOL:
+        return new BoolConstantExpression(
+            decoder.getBool(Key.VALUE));
+      case ConstantExpressionKind.BOOL_FROM_ENVIRONMENT:
+        return new BoolFromEnvironmentConstantExpression(
+            decoder.getConstant(Key.NAME),
+            decoder.getConstant(Key.DEFAULT, isOptional: true));
+      case ConstantExpressionKind.CONCATENATE:
+        return new ConcatenateConstantExpression(
+            decoder.getConstants(Key.ARGUMENTS));
+      case ConstantExpressionKind.CONDITIONAL:
+        return new ConditionalConstantExpression(
+            decoder.getConstant(Key.CONDITION),
+            decoder.getConstant(Key.TRUE),
+            decoder.getConstant(Key.FALSE));
+      case ConstantExpressionKind.CONSTRUCTED:
+        List<String> names =
+            decoder.getStrings(Key.NAMES, isOptional: true);
+        List<ConstantExpression> arguments =
+              decoder.getConstants(Key.ARGUMENTS, isOptional: true);
+        return new ConstructedConstantExpression(
+            decoder.getType(Key.TYPE),
+            decoder.getElement(Key.ELEMENT),
+            new CallStructure(arguments.length, names),
+            arguments);
+      case ConstantExpressionKind.DOUBLE:
+        return new DoubleConstantExpression(decoder.getDouble(Key.VALUE));
+      case ConstantExpressionKind.ERRONEOUS:
+        break;
+      case ConstantExpressionKind.FUNCTION:
+        return new FunctionConstantExpression(
+            decoder.getElement(Key.ELEMENT));
+      case ConstantExpressionKind.IDENTICAL:
+        return new IdenticalConstantExpression(
+            decoder.getConstant(Key.LEFT),
+            decoder.getConstant(Key.RIGHT));
+      case ConstantExpressionKind.INT:
+        return new IntConstantExpression(decoder.getInt(Key.VALUE));
+      case ConstantExpressionKind.INT_FROM_ENVIRONMENT:
+        return new IntFromEnvironmentConstantExpression(
+            decoder.getConstant(Key.NAME),
+            decoder.getConstant(Key.DEFAULT, isOptional: true));
+      case ConstantExpressionKind.LIST:
+        return new ListConstantExpression(
+            decoder.getType(Key.TYPE),
+            decoder.getConstants(Key.VALUES));
+      case ConstantExpressionKind.MAP:
+        return new MapConstantExpression(
+            decoder.getType(Key.TYPE),
+            decoder.getConstants(Key.KEYS),
+            decoder.getConstants(Key.VALUES));
+      case ConstantExpressionKind.NULL:
+        return new NullConstantExpression();
+      case ConstantExpressionKind.STRING:
+        return new StringConstantExpression(
+            decoder.getString(Key.VALUE));
+      case ConstantExpressionKind.STRING_FROM_ENVIRONMENT:
+        return new StringFromEnvironmentConstantExpression(
+            decoder.getConstant(Key.NAME),
+            decoder.getConstant(Key.DEFAULT, isOptional: true));
+      case ConstantExpressionKind.STRING_LENGTH:
+        return new StringLengthConstantExpression(
+            decoder.getConstant(Key.EXPRESSION));
+      case ConstantExpressionKind.SYMBOL:
+        break;
+      case ConstantExpressionKind.TYPE:
+        return new TypeConstantExpression(decoder.getType(Key.TYPE));
+      case ConstantExpressionKind.UNARY:
+        UnaryOperator operator = UnaryOperator.fromKind(
+            decoder.getEnum(Key.OPERATOR, UnaryOperatorKind.values));
+        return new UnaryConstantExpression(
+            operator,
+            decoder.getConstant(Key.EXPRESSION));
+      case ConstantExpressionKind.VARIABLE:
+        return new VariableConstantExpression(
+            decoder.getElement(Key.ELEMENT));
+
+      case ConstantExpressionKind.POSITIONAL_REFERENCE:
+        return new PositionalArgumentReference(
+            decoder.getInt(Key.INDEX));
+      case ConstantExpressionKind.NAMED_REFERENCE:
+        return new NamedArgumentReference(
+            decoder.getString(Key.NAME));
+      case ConstantExpressionKind.DEFERRED:
+      case ConstantExpressionKind.SYNTHETIC:
+    }
+    throw new UnsupportedError(
+        "Unexpected constant kind: ${kind} in $decoder");
+  }
+}
+
+/// Visitor that serializes a [ConstantConstructor] by encoding it into an
+/// [ObjectEncoder].
+///
+/// This class is called from the [ConstructorSerializer] when the [Serializer]
+/// is serializing constant constructor. The [ObjectEncoder] ensures that any
+/// [Element], [DartType], and [ConstantExpression] that the serialized
+/// [ConstantConstructor] depends upon are also serialized.
+class ConstantConstructorSerializer
+    extends ConstantConstructorVisitor<dynamic, ObjectEncoder> {
+  const ConstantConstructorSerializer();
+
+  @override
+  void visit(ConstantConstructor constantConstructor,
+             ObjectEncoder encoder) {
+    encoder.setEnum(Key.KIND, constantConstructor.kind);
+    constantConstructor.accept(this, encoder);
+  }
+
+  @override
+  void visitGenerative(
+      GenerativeConstantConstructor constructor,
+      ObjectEncoder encoder) {
+    encoder.setType(Key.TYPE, constructor.type);
+    MapEncoder defaults = encoder.createMap(Key.DEFAULTS);
+    constructor.defaultValues.forEach((key, e) {
+      defaults.setConstant('$key', e);
+    });
+    ListEncoder fields = encoder.createList(Key.FIELDS);
+    constructor.fieldMap.forEach((FieldElement f, ConstantExpression e) {
+      ObjectEncoder fieldSerializer = fields.createObject();
+      fieldSerializer.setElement(Key.FIELD, f);
+      fieldSerializer.setConstant(Key.CONSTANT, e);
+    });
+    if (constructor.superConstructorInvocation != null) {
+      encoder.setConstant(Key.CONSTRUCTOR,
+          constructor.superConstructorInvocation);
+    }
+  }
+
+  @override
+  void visitRedirectingFactory(
+      RedirectingFactoryConstantConstructor constructor,
+      ObjectEncoder encoder) {
+    encoder.setConstant(Key.CONSTRUCTOR,
+        constructor.targetConstructorInvocation);
+  }
+
+  @override
+  void visitRedirectingGenerative(
+      RedirectingGenerativeConstantConstructor constructor,
+      ObjectEncoder encoder) {
+    MapEncoder defaults = encoder.createMap(Key.DEFAULTS);
+    constructor.defaultValues.forEach((key, ConstantExpression e) {
+      defaults.setConstant('$key', e);
+    });
+    encoder.setConstant(Key.CONSTRUCTOR,
+        constructor.thisConstructorInvocation);
+  }
+}
+/// Utility class for deserializing [ConstantConstructor]s.
+///
+/// This is used by the [ConstructorElementZ].
+class ConstantConstructorDeserializer {
+  /// Deserializes a [ConstantConstructor] from an [ObjectDecoder].
+  ///
+  /// The class is called from the [Deserializer] when a constant constructor
+  /// needs deserialization. The [ObjectDecoder] ensures that any [Element],
+  /// [DartType], and [ConstantExpression] that the deserialized
+  /// [ConstantConstructor] depends upon are available.
+  static ConstantConstructor deserialize(ObjectDecoder decoder) {
+
+    ConstantConstructorKind kind =
+        decoder.getEnum(Key.KIND, ConstantConstructorKind.values);
+
+    DartType readType() {
+      return decoder.getType(Key.TYPE);
+    }
+
+    Map<dynamic/*int|String*/, ConstantExpression> readDefaults() {
+      Map<dynamic, ConstantExpression> defaultValues =
+          <dynamic, ConstantExpression>{};
+      if (decoder.containsKey(Key.DEFAULTS)) {
+        MapDecoder defaultsMap = decoder.getMap(Key.DEFAULTS);
+        defaultsMap.forEachKey((String key) {
+          int index = int.parse(key, onError: (_) => null);
+          if (index != null) {
+            defaultValues[index] = defaultsMap.getConstant(key);
+          } else {
+            defaultValues[key] = defaultsMap.getConstant(key);
+          }
+        });
+      }
+      return defaultValues;
+    }
+
+    Map<FieldElement, ConstantExpression> readFields() {
+      Map<FieldElement, ConstantExpression> fieldMap =
+          <FieldElement, ConstantExpression>{};
+      if (decoder.containsKey(Key.FIELDS)) {
+        ListDecoder fieldsList = decoder.getList(Key.FIELDS);
+        for (int i = 0; i < fieldsList.length; i++) {
+          ObjectDecoder object = fieldsList.getObject(i);
+          FieldElement field = object.getElement(Key.FIELD);
+          ConstantExpression constant = object.getConstant(Key.CONSTANT);
+          fieldMap[field] = constant;
+        }
+      }
+      return fieldMap;
+    }
+
+    ConstructedConstantExpression readConstructorInvocation() {
+      return decoder.getConstant(Key.CONSTRUCTOR, isOptional: true);
+    }
+
+    switch (kind) {
+      case ConstantConstructorKind.GENERATIVE:
+        return new GenerativeConstantConstructor(
+            readType(),
+            readDefaults(),
+            readFields(),
+            readConstructorInvocation());
+      case ConstantConstructorKind.REDIRECTING_GENERATIVE:
+        return new RedirectingGenerativeConstantConstructor(
+            readDefaults(),
+            readConstructorInvocation());
+      case ConstantConstructorKind.REDIRECTING_FACTORY:
+        return new RedirectingFactoryConstantConstructor(
+            readConstructorInvocation());
+    }
+  }
+}