Collect the types used in is-checks in the resolver phase.

lib/compiler/implementation/universe.dart

 // Copyright (c) 2012, 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.
 
 class Universe {
   Map<Element, CodeBuffer> generatedCode;
   Map<Element, CodeBuffer> generatedBailoutCode;
   final Set<ClassElement> instantiatedClasses;
   final Set<SourceString> instantiatedClassInstanceFields;
   final Set<FunctionElement> staticFunctionsNeedingGetter;
   final Map<SourceString, Set<Selector>> invokedNames;
   final Map<SourceString, Set<Selector>> invokedGetters;
   final Map<SourceString, Set<Selector>> invokedSetters;
   final Map<SourceString, Set<Selector>> fieldGetters;
   final Map<SourceString, Set<Selector>> fieldSetters;
-  // TODO(ngeoffray): This should be a Set<Type>.
-  final Set<Element> isChecks;
+  final Set<Type> isChecks;
+  // TODO(karlklose): move this data to RuntimeTypeInformation.
+  Set<Element> checkedClasses;
+
   final RuntimeTypeInformation rti;
 
   Universe() : generatedCode = new Map<Element, CodeBuffer>(),
                generatedBailoutCode = new Map<Element, CodeBuffer>(),
                instantiatedClasses = new Set<ClassElement>(),
                instantiatedClassInstanceFields = new Set<SourceString>(),
                staticFunctionsNeedingGetter = new Set<FunctionElement>(),
                invokedNames = new Map<SourceString, Set<Selector>>(),
                invokedGetters = new Map<SourceString, Set<Selector>>(),
                invokedSetters = new Map<SourceString, Set<Selector>>(),
                fieldGetters = new Map<SourceString, Set<Selector>>(),
                fieldSetters = new Map<SourceString, Set<Selector>>(),
-               isChecks = new Set<Element>(),
+               isChecks = new Set<Type>(),
                rti = new RuntimeTypeInformation();
 
+  // TODO(karlklose): the second argument should be a  set of types, too.

[ngeoffray, 2012/08/30 13:17:46]

The second argument is not used.

[karlklose, 2012/09/05 09:36:01]

Done, removed.

+  void computeRequiredTypes(Set<Type> isChecks,
+                            Set<Element> instantiatedTypes) {
+    assert(checkedClasses == null);
+    checkedClasses = new Set<Element>();
+    isChecks.forEach((Type t) => checkedClasses.add(t.element));
+  }
+
   void addGeneratedCode(WorkItem work, CodeBuffer codeBuffer) {
     generatedCode[work.element] = codeBuffer;
   }
 
   void addBailoutCode(WorkItem work, CodeBuffer codeBuffer) {
     generatedBailoutCode[work.element] = codeBuffer;
   }
 
   bool hasMatchingSelector(Set<Selector> selectors,
                            Element member,
@@ skipping 343 matching lines @@
     }
 
     return false;
   }
 
   toString() {
     return 'Selector($kind, "${name.slowToString()}", '
            '$argumentCount, type=$receiverType)';
   }
 }