Include constants in deferred computation.

This ensures that in-code constants are included in the deferred computation.

Currently the set of live constants is not computed in itself, so the constants
used in the computation are not the same - and they are generally larger than needed.

R=het@google.com

Review URL: https://codereview.chromium.org/2194173002 .

pkg/compiler/lib/src/constants/expressions.dart

@@ -133,7 +133,7 @@ abstract class ConstantExpression {
   /// if it contains positional or named references, used to define constant
   /// constructors.
   // TODO(johnniwinther): Maybe make this final if we use it outside assertions.
-  bool get isPotential => true;
+  bool get isPotential => false;
 }
 
 /// A synthetic constant used to recover from errors.
@@ -194,9 +194,6 @@ class SyntheticConstantExpression extends ConstantExpression {
 
   ConstantExpressionKind get kind => ConstantExpressionKind.SYNTHETIC;
 
-  @override
-  bool get isPotential => false;
-
   @override
   bool get isImplicit => false;
 }
@@ -1270,9 +1267,7 @@ class PositionalArgumentReference extends ConstantExpression {
   }
 
   @override
-  bool get isPotential {
-    return true;
-  }
+  bool get isPotential => true;
 }
 
 /// A reference to a named parameter.
@@ -1311,9 +1306,7 @@ class NamedArgumentReference extends ConstantExpression {
   }
 
   @override
-  bool get isPotential {
-    return true;
-  }
+  bool get isPotential => true;
 }
 
 abstract class FromEnvironmentConstantExpression extends ConstantExpression {

pkg/compiler/lib/src/deferred_load.dart

@@ -180,12 +180,22 @@ class DeferredLoadTask extends CompilerTask {
     return _elementToOutputUnit[element];
   }
 
+  /// Direct access to the output-unit to element relation used for testing.
+  OutputUnit getOutputUnitForElementForTesting(Element element) {
+    return _elementToOutputUnit[element];
+  }
+
   /// Returns the [OutputUnit] where [constant] belongs.
   OutputUnit outputUnitForConstant(ConstantValue constant) {
     if (!isProgramSplit) return mainOutputUnit;
     return _constantToOutputUnit[constant];
   }
 
+  /// Direct access to the output-unit to constants map used for testing.
+  Map<ConstantValue, OutputUnit> get outputUnitForConstantsForTesting {
+    return _constantToOutputUnit;
+  }
+
   bool isDeferred(Element element) {
     return outputUnitForElement(element) != mainOutputUnit;
   }
@@ -348,7 +358,7 @@ class DeferredLoadTask extends CompilerTask {
         treeElements.forEachConstantNode(
             (ast.Node node, ConstantExpression expression) {
           if (compiler.serialization.isDeserialized(analyzableElement)) {
-            if (!expression.isImplicit && !expression.isPotential) {
+            if (!expression.isPotential) {
               // Enforce evaluation of [expression].
               backend.constants.getConstantValue(expression);
             }
@@ -926,7 +936,8 @@ class DeferredLoadTask extends CompilerTask {
 
     StringBuffer sb = new StringBuffer();
     for (OutputUnit outputUnit in allOutputUnits) {
-      sb.write(outputUnit.name);
+      sb.write('\n-------------------------------\n');
+      sb.write('Output unit: ${outputUnit.name}');
       List<String> elements = elementMap[outputUnit];
       if (elements != null) {
         sb.write('\n elements:');

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

@@ -10,6 +10,7 @@ import '../closure.dart';
 import '../common.dart';
 import '../common/resolution.dart';
 import '../constants/expressions.dart';
+import '../constants/values.dart';
 import '../dart_types.dart';
 import '../elements/elements.dart';
 import '../elements/visitor.dart';
@@ -63,6 +64,31 @@ bool areSetsEquivalent(Iterable set1, Iterable set2,
   return remaining.isEmpty;
 }
 
+/// Returns `true` if the content of [map1] and [map2] is equivalent using
+/// [keyEquivalence] and [valueEquivalence] to determine key/value equivalence.
+bool areMapsEquivalent(Map map1, Map map2,
+    [bool keyEquivalence(a, b) = equality,
+    bool valueEquivalence(a, b) = equality]) {
+  Set remaining = map2.keys.toSet();
+  for (var key1 in map1.keys) {
+    bool found = false;
+    for (var key2 in map2.keys) {
+      if (keyEquivalence(key2, key2)) {
+        found = true;
+        remaining.remove(key2);
+        if (!valueEquivalence(map1[key1], map2[key2])) {
+          return false;
+        }
+        break;
+      }
+    }
+    if (!found) {
+      return false;
+    }
+  }
+  return remaining.isEmpty;
+}
+
 /// Returns `true` if elements [a] and [b] are equivalent.
 bool areElementsEquivalent(Element a, Element b) {
   if (identical(a, b)) return true;
@@ -77,13 +103,20 @@ bool areTypesEquivalent(DartType a, DartType b) {
   return const TypeEquivalence().visit(a, b);
 }
 
-/// Returns `true` if constants [a] and [b] are equivalent.
+/// Returns `true` if constants [exp1] and [exp2] are equivalent.
 bool areConstantsEquivalent(ConstantExpression exp1, ConstantExpression exp2) {
   if (identical(exp1, exp2)) return true;
   if (exp1 == null || exp2 == null) return false;
   return const ConstantEquivalence().visit(exp1, exp2);
 }
 
+/// Returns `true` if constant values [value1] and [value2] are equivalent.
+bool areConstantValuesEquivalent(ConstantValue value1, ConstantValue value2) {
+  if (identical(value1, value2)) return true;
+  if (value1 == null || value2 == null) return false;
+  return const ConstantValueEquivalence().visit(value1, value2);
+}
+
 /// Returns `true` if the lists of elements, [a] and [b], are equivalent.
 bool areElementListsEquivalent(List<Element> a, List<Element> b) {
   return areListsEquivalent(a, b, areElementsEquivalent);
@@ -100,6 +133,12 @@ bool areConstantListsEquivalent(
   return areListsEquivalent(a, b, areConstantsEquivalent);
 }
 
+/// Returns `true` if the lists of constant values, [a] and [b], are equivalent.
+bool areConstantValueListsEquivalent(
+    List<ConstantValue> a, List<ConstantValue> b) {
+  return areListsEquivalent(a, b, areConstantValuesEquivalent);
+}
+
 /// Returns `true` if the selectors [a] and [b] are equivalent.
 bool areSelectorsEquivalent(Selector a, Selector b) {
   if (identical(a, b)) return true;
@@ -307,6 +346,12 @@ class TestStrategy {
     return areSetsEquivalent(set1, set2, elementEquivalence);
   }
 
+  bool testMaps(var object1, var object2, String property, Map map1, Map map2,
+      [bool keyEquivalence(a, b) = equality,
+      bool valueEquivalence(a, b) = equality]) {
+    return areMapsEquivalent(map1, map2, keyEquivalence, valueEquivalence);
+  }
+
   bool testElements(Object object1, Object object2, String property,
       Element element1, Element element2) {
     return areElementsEquivalent(element1, element2);
@@ -322,6 +367,11 @@ class TestStrategy {
     return areConstantsEquivalent(exp1, exp2);
   }
 
+  bool testConstantValues(Object object1, Object object2, String property,
+      ConstantValue value1, ConstantValue value2) {
+    return areConstantValuesEquivalent(value1, value2);
+  }
+
   bool testTypeLists(Object object1, Object object2, String property,
       List<DartType> list1, List<DartType> list2) {
     return areTypeListsEquivalent(list1, list2);
@@ -332,6 +382,11 @@ class TestStrategy {
     return areConstantListsEquivalent(list1, list2);
   }
 
+  bool testConstantValueLists(Object object1, Object object2, String property,
+      List<ConstantValue> list1, List<ConstantValue> list2) {
+    return areConstantValueListsEquivalent(list1, list2);
+  }
+
   bool testNodes(
       Object object1, Object object2, String property, Node node1, Node node2) {
     return areNodesEquivalent(node1, node2);
@@ -780,9 +835,130 @@ class ConstantEquivalence
   @override
   bool visitDeferred(
       DeferredConstantExpression exp1, DeferredConstantExpression exp2) {
-    // TODO(johnniwinther): Implement this.
+    return strategy.testElements(
+            exp1, exp2, 'prefix', exp1.prefix, exp2.prefix) &&
+        strategy.testConstants(
+            exp1, exp2, 'expression', exp1.expression, exp2.expression);
+  }
+}
+
+/// Visitor that checks for structural equivalence of [ConstantValue]s.
+class ConstantValueEquivalence
+    implements ConstantValueVisitor<bool, ConstantValue> {
+  final TestStrategy strategy;
+
+  const ConstantValueEquivalence([this.strategy = const TestStrategy()]);
+
+  bool visit(ConstantValue value1, ConstantValue value2) {
+    if (identical(value1, value2)) return true;
+    return strategy.test(value1, value2, 'kind', value1.kind, value2.kind) &&
+        value1.accept(this, value2);
+  }
+
+  @override
+  bool visitConstructed(
+      ConstructedConstantValue value1, ConstructedConstantValue value2) {
+    return strategy.testTypes(
+            value1, value2, 'type', value1.type, value2.type) &&
+        strategy.testMaps(
+            value1,
+            value2,
+            'fields',
+            value1.fields,
+            value2.fields,
+            areElementsEquivalent,
+            (a, b) => strategy.testConstantValues(
+                value1, value2, 'fields.values', a, b));
+  }
+
+  @override
+  bool visitFunction(
+      FunctionConstantValue value1, FunctionConstantValue value2) {
+    return strategy.testElements(
+        value1, value2, 'element', value1.element, value2.element);
+  }
+
+  @override
+  bool visitList(ListConstantValue value1, ListConstantValue value2) {
+    return strategy.testTypes(
+            value1, value2, 'type', value1.type, value2.type) &&
+        strategy.testConstantValueLists(
+            value1, value2, 'entries', value1.entries, value2.entries);
+  }
+
+  @override
+  bool visitMap(MapConstantValue value1, MapConstantValue value2) {
+    return strategy.testTypes(
+            value1, value2, 'type', value1.type, value2.type) &&
+        strategy.testConstantValueLists(
+            value1, value2, 'keys', value1.keys, value2.keys) &&
+        strategy.testConstantValueLists(
+            value1, value2, 'values', value1.values, value2.values);
+  }
+
+  @override
+  bool visitType(TypeConstantValue value1, TypeConstantValue value2) {
+    return strategy.testTypes(value1, value2, 'type', value1.type, value2.type);
+  }
+
+  @override
+  bool visitBool(BoolConstantValue value1, BoolConstantValue value2) {
+    return strategy.test(value1, value2, 'primitiveValue',
+        value1.primitiveValue, value2.primitiveValue);
+  }
+
+  @override
+  bool visitDouble(DoubleConstantValue value1, DoubleConstantValue value2) {
+    return strategy.test(value1, value2, 'primitiveValue',
+        value1.primitiveValue, value2.primitiveValue);
+  }
+
+  @override
+  bool visitInt(IntConstantValue value1, IntConstantValue value2) {
+    return strategy.test(value1, value2, 'primitiveValue',
+        value1.primitiveValue, value2.primitiveValue);
+  }
+
+  @override
+  bool visitNull(NullConstantValue value1, NullConstantValue value2) {
     return true;
   }
+
+  @override
+  bool visitString(StringConstantValue value1, StringConstantValue value2) {
+    return strategy.test(value1, value2, 'primitiveValue',
+        value1.primitiveValue, value2.primitiveValue);
+  }
+
+  @override
+  bool visitDeferred(
+      DeferredConstantValue value1, DeferredConstantValue value2) {
+    return strategy.testElements(
+            value1, value2, 'prefix', value1.prefix, value2.prefix) &&
+        strategy.testConstantValues(
+            value1, value2, 'referenced', value1.referenced, value2.referenced);
+  }
+
+  @override
+  bool visitNonConstant(NonConstantValue value1, NonConstantValue value2) {
+    return true;
+  }
+
+  @override
+  bool visitSynthetic(
+      SyntheticConstantValue value1, SyntheticConstantValue value2) {
+    return strategy.test(
+            value1, value2, 'payload', value1.payload, value2.payload) &&
+        strategy.test(
+            value1, value2, 'valueKind', value1.valueKind, value2.valueKind);
+  }
+
+  @override
+  bool visitInterceptor(
+      InterceptorConstantValue value1, InterceptorConstantValue value2) {
+    return strategy.testTypes(value1, value2, 'dispatchedType',
+        value1.dispatchedType, value2.dispatchedType);
+  }
 }
 
 /// Tests the equivalence of [impact1] and [impact2] using [strategy].

tests/compiler/dart2js/serialization/model_test_helper.dart

@@ -11,6 +11,7 @@ import 'package:expect/expect.dart';
 import 'package:compiler/src/closure.dart';
 import 'package:compiler/src/commandline_options.dart';
 import 'package:compiler/src/common.dart';
+import 'package:compiler/src/constants/values.dart';
 import 'package:compiler/src/compiler.dart';
 import 'package:compiler/src/deferred_load.dart';
 import 'package:compiler/src/elements/elements.dart';
@@ -161,6 +162,38 @@ Future checkModels(
         compilerNormal.deferredLoadTask.isProgramSplit,
         compilerDeserialized.deferredLoadTask.isProgramSplit,
         "isProgramSplit mismatch");
+
+    Map<ConstantValue, OutputUnit> constants1 =
+        compilerNormal.deferredLoadTask.outputUnitForConstantsForTesting;
+    Map<ConstantValue, OutputUnit> constants2 =
+        compilerDeserialized.deferredLoadTask.outputUnitForConstantsForTesting;
+    checkSets(
+        constants1.keys,
+        constants2.keys,
+        'deferredLoadTask._outputUnitForConstants.keys',
+        areConstantValuesEquivalent,
+        failOnUnfound: false,
+        failOnExtra: false,
+        onSameElement: (ConstantValue value1, ConstantValue value2) {
+          OutputUnit outputUnit1 = constants1[value1];
+          OutputUnit outputUnit2 = constants2[value2];
+          checkOutputUnits(outputUnit1, outputUnit2,
+              'for ${value1.toStructuredText()} '
+                  'vs ${value2.toStructuredText()}');
+        },
+        onUnfoundElement: (ConstantValue value1) {
+          OutputUnit outputUnit1 = constants1[value1];
+          Expect.isTrue(outputUnit1.isMainOutput,
+              "Missing deferred constant: ${value1.toStructuredText()}");
+        },
+        onExtraElement: (ConstantValue value2) {
+          OutputUnit outputUnit2 = constants2[value2];
+          Expect.isTrue(outputUnit2.isMainOutput,
+              "Extra deferred constant: ${value2.toStructuredText()}");
+        },
+        elementToString: (a) {
+          return '${a.toStructuredText()} -> ${constants1[a]}/${constants2[a]}';
+        });
   });
 }
 
@@ -244,7 +277,7 @@ void checkElements(
       backend2.inlineCache.getCurrentCacheDecisionForTesting(element2),
       "Inline cache decision mismatch for $element1 vs $element2");
 
-  checkOutputUnits(compiler1, compiler2, element1, element2);
+  checkElementOutputUnits(compiler1, compiler2, element1, element2);
 }
 
 void checkMixinUses(
@@ -360,17 +393,24 @@ String nodeToString(Node node) {
   return '(${node.runtimeType}) $text';
 }
 
-void checkOutputUnits(Compiler compiler1, Compiler compiler2, Element element1,
-    Element element2) {
+void checkElementOutputUnits(
+    Compiler compiler1, Compiler compiler2,
+    Element element1, Element element2) {
   OutputUnit outputUnit1 =
-      compiler1.deferredLoadTask.outputUnitForElement(element1);
+      compiler1.deferredLoadTask.getOutputUnitForElementForTesting(element1);
   OutputUnit outputUnit2 =
-      compiler2.deferredLoadTask.outputUnitForElement(element2);
+      compiler2.deferredLoadTask.getOutputUnitForElementForTesting(element2);
+  checkOutputUnits(outputUnit1, outputUnit2, 'for $element1 vs $element2');
+}
+
+void checkOutputUnits(
+    OutputUnit outputUnit1, OutputUnit outputUnit2, String message) {
+  if (outputUnit1 == null && outputUnit2 == null) return;
   check(outputUnit1, outputUnit2,
-      'OutputUnit.isMainOutput for $element1 vs $element2',
+      'OutputUnit.isMainOutput $message',
       outputUnit1.isMainOutput, outputUnit2.isMainOutput);
   checkSetEquivalence(outputUnit1, outputUnit2,
-      'OutputUnit.imports for $element1 vs $element2',
+      'OutputUnit.imports $message',
       outputUnit1.imports, outputUnit2.imports,
       (a, b) => areElementsEquivalent(a.declaration, b.declaration));
 }

tests/compiler/dart2js/serialization/test_data.dart

@@ -642,6 +642,35 @@ import "dart:core" deferred as core;
 test() {
   core.loadLibrary().then((_) => null);
 }
+''',
+  }),
+
+  const Test('Use of dart:indexed_db', const {
+    'main.dart': '''
+import 'a.dart';
+
+main() {}
+''',
+  }, preserializedSourceFiles: const {
+    'a.dart': '''
+import 'dart:indexed_db';
+''',
+  }),
+
+  const Test('Deferred static access', const {},
+      preserializedSourceFiles: const {
+    'main.dart': '''
+import 'b.dart' deferred as prefix;
+
+main() => prefix.loadLibrary().then((_) => prefix.test2());
+''',
+    'b.dart': '''
+test2() => x;
+var x = const ConstClass(const ConstClass(1));
+class ConstClass {
+  final x;
+  const ConstClass(this.x);
+}
 ''',
   }),
 ];

tests/compiler/dart2js/serialization/test_helper.dart

@@ -7,6 +7,7 @@ library dart2js.serialization_test_helper;
 import 'dart:collection';
 import 'package:compiler/src/common/resolution.dart';
 import 'package:compiler/src/constants/expressions.dart';
+import 'package:compiler/src/constants/values.dart';
 import 'package:compiler/src/dart_types.dart';
 import 'package:compiler/src/compiler.dart';
 import 'package:compiler/src/elements/elements.dart';
@@ -87,6 +88,15 @@ class CheckStrategy implements TestStrategy {
         object1, object2,property, set1, set2, elementEquivalence);
   }
 
+  @override
+  bool testMaps(
+      var object1, var object2, String property, Map map1, Map map2,
+      [bool keyEquivalence(a, b) = equality,
+      bool valueEquivalence(a, b) = equality]) {
+    return checkMapEquivalence(object1, object2, property,
+        map1, map2, keyEquivalence, valueEquivalence);
+  }
+
   @override
   bool testElements(
       Object object1, Object object2, String property,
@@ -109,6 +119,12 @@ class CheckStrategy implements TestStrategy {
     return checkConstants(object1, object2, property, exp1, exp2);
   }
 
+  @override
+  bool testConstantValues(Object object1, Object object2, String property,
+      ConstantValue value1, ConstantValue value2) {
+    return areConstantValuesEquivalent(value1, value2);
+  }
+
   @override
   bool testTypeLists(
       Object object1, Object object2, String property,
@@ -124,6 +140,12 @@ class CheckStrategy implements TestStrategy {
     return checkConstantLists(object1, object2, property, list1, list2);
   }
 
+  @override
+  bool testConstantValueLists(Object object1, Object object2, String property,
+      List<ConstantValue> list1, List<ConstantValue> list2) {
+    return checkConstantValueLists(object1, object2, property, list1, list2);
+  }
+
   @override
   bool testNodes(Object object1, Object object2, String property,
       Node node1, Node node2) {
@@ -247,6 +269,38 @@ bool checkSetEquivalence(
   return true;
 }
 
+/// Check equivalence of the two iterables, [set1] and [set1], as sets using
+/// [elementEquivalence] to compute the pair-wise equivalence.
+///
+/// Uses [object1], [object2] and [property] to provide context for failures.
+bool checkMapEquivalence(
+    var object1,
+    var object2,
+    String property,
+    Map map1,
+    Map map2,
+    bool sameKey(a, b),
+    bool sameValue(a, b)) {
+  List<List> common = <List>[];
+  List unfound = [];
+  Set remaining =
+      computeSetDifference(map1.keys, map2.keys, common, unfound,
+          sameElement: sameKey);
+  if (unfound.isNotEmpty || remaining.isNotEmpty) {
+    String message =
+        "Map key mismatch for `$property` on $object1 vs $object2: \n"
+        "Common:\n ${common.join('\n ')}\n"
+        "Unfound:\n ${unfound.join('\n ')}\n"
+        "Extra: \n ${remaining.join('\n ')}";
+    throw message;
+  }
+  for (List pair in common) {
+    check(object1, object2, 'Map value for `$property`',
+        map1[pair[0]], map2[pair[1]], sameValue);
+  }
+  return true;
+}
+
 /// Checks the equivalence of the identity (but not properties) of [element1]
 /// and [element2].
 ///
@@ -311,7 +365,23 @@ bool checkConstants(
   }
 }
 
-/// Checks the pair-wise equivalence of the contants in [list1] and [list2].
+/// Checks the equivalence of [value1] and [value2].
+///
+/// Uses [object1], [object2] and [property] to provide context for failures.
+bool checkConstantValues(
+    Object object1, Object object2, String property,
+    ConstantValue value1, ConstantValue value2) {
+  if (identical(value1, value2)) return true;
+  if (value1 == null || value2 == null) {
+    return check(object1, object2, property, value1, value2);
+  } else {
+    return check(object1, object2, property, value1, value2,
+        (a, b) => const ConstantValueEquivalence(
+            const CheckStrategy()).visit(a, b));
+  }
+}
+
+/// Checks the pair-wise equivalence of the constants in [list1] and [list2].
 ///
 /// Uses [object1], [object2] and [property] to provide context for failures.
 bool checkConstantLists(
@@ -323,6 +393,18 @@ bool checkConstantLists(
       list1, list2, checkConstants);
 }
 
+/// Checks the pair-wise equivalence of the constants values in [list1] and
+/// [list2].
+///
+/// Uses [object1], [object2] and [property] to provide context for failures.
+bool checkConstantValueLists(
+    Object object1, Object object2, String property,
+    List<ConstantValue> list1,
+    List<ConstantValue> list2) {
+  return checkListEquivalence(
+      object1, object2, property,
+      list1, list2, checkConstantValues);
+}
 
 /// Check member property equivalence between all members common to [compiler1]
 /// and [compiler2].
@@ -439,27 +521,41 @@ void checkSets(
     {bool failOnUnfound: true,
     bool failOnExtra: true,
     bool verbose: false,
-    void onSameElement(a, b)}) {
+    void onSameElement(a, b),
+    void onUnfoundElement(a),
+    void onExtraElement(b),
+    String elementToString(key): defaultToString}) {
   List<List> common = <List>[];
   List unfound = [];
   Set remaining = computeSetDifference(
       set1, set2, common, unfound,
       sameElement: sameElement,
       checkElements: onSameElement);
+  if (onUnfoundElement != null) {
+    unfound.forEach(onUnfoundElement);
+  }
+  if (onExtraElement != null) {
+    remaining.forEach(onExtraElement);
+  }
   StringBuffer sb = new StringBuffer();
   sb.write("$messagePrefix:");
   if (verbose) {
-    sb.write("\n Common:\n  ${common.join('\n  ')}");
+    sb.write("\n Common: \n");
+    for (List pair in common) {
+      var element1 = pair[0];
+      var element2 = pair[1];
+      sb.write("  [${elementToString(element1)},"
+          "${elementToString(element2)}]\n");
+    }
   }
   if (unfound.isNotEmpty || verbose) {
-    sb.write("\n Unfound:\n  ${unfound.join('\n  ')}");
+    sb.write("\n Unfound:\n  ${unfound.map(elementToString).join('\n  ')}");
   }
   if (remaining.isNotEmpty || verbose) {
-    sb.write("\n Extra: \n  ${remaining.join('\n  ')}");
+    sb.write("\n Extra: \n  ${remaining.map(elementToString).join('\n  ')}");
   }
   String message = sb.toString();
   if (unfound.isNotEmpty || remaining.isNotEmpty) {
-
     if ((failOnUnfound && unfound.isNotEmpty) ||
         (failOnExtra && remaining.isNotEmpty)) {
       Expect.fail(message);