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

lib/compiler/implementation/universe.dart

Index: lib/compiler/implementation/universe.dart
diff --git a/lib/compiler/implementation/universe.dart b/lib/compiler/implementation/universe.dart
index 976f06beef56e16aef544a4f315df1d6d69e3af7..41f220d3783bb907e8050c8a9e0e5e83e21d72fc 100644
--- a/lib/compiler/implementation/universe.dart
+++ b/lib/compiler/implementation/universe.dart
@@ -13,8 +13,10 @@ class Universe {
   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> cachedCheckedClasses;
+
   final RuntimeTypeInformation rti;
 
   Universe() : generatedCode = new Map<Element, CodeBuffer>(),
@@ -27,9 +29,17 @@ class Universe {
                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();
 
+  get checkedClasses {

[ngeoffray, 2012/08/30 11:03:33]

What is that for? Why not using isChecks?

[karlklose, 2012/08/30 13:04:31]

Currently, the code emitter generates the is$-methods based on elements. Instead
of running through the isChecks multiple times to find out whether there is a
type with the matching element in the set, I create this set once.

+    if (cachedCheckedClasses == null) {
+      cachedCheckedClasses = new Set<Element>();
+      isChecks.forEach((Type t) => cachedCheckedClasses.add(t.element));
+    }
+    return cachedCheckedClasses;
+  }
+
   void addGeneratedCode(WorkItem work, CodeBuffer codeBuffer) {
     generatedCode[work.element] = codeBuffer;
   }