Optimize subclass/subtype queries

pkg/compiler/lib/src/ssa/builder.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.
 
 part of ssa;
 
 class SsaFunctionCompiler implements FunctionCompiler {
   final SsaCodeGeneratorTask generator;
   final SsaBuilderTask builder;
   final SsaOptimizerTask optimizer;
@@ skipping 4822 matching lines @@
     Selector selector = elements.getSelector(node);
     List<HInstruction> inputs = <HInstruction>[];
     addGenericSendArgumentsToList(arguments.nodes, inputs);
     generateSuperNoSuchMethodSend(node, selector, inputs);
   }
 
   bool needsSubstitutionForTypeVariableAccess(ClassElement cls) {
     ClassWorld classWorld = compiler.world;
     if (classWorld.isUsedAsMixin(cls)) return true;
 
-    Iterable<ClassElement> subclasses = compiler.world.strictSubclassesOf(cls);
-    return subclasses.any((ClassElement subclass) {
+    return compiler.world.anyStrictSubclassOf(cls, (ClassElement subclass) {
       return !rti.isTrivialSubstitution(subclass, cls);
     });
   }
 
   /**
    * Generate code to extract the type arguments from the object, substitute
    * them as an instance of the type we are testing against (if necessary), and
    * extract the type argument by the index of the variable in the list of type
    * variables for that class.
    */
@@ skipping 4374 matching lines @@
     if (unaliased is TypedefType) throw 'unable to unalias $type';
     unaliased.accept(this, builder);
   }
 
   void visitDynamicType(DynamicType type, SsaBuilder builder) {
     JavaScriptBackend backend = builder.compiler.backend;
     ClassElement cls = backend.helpers.DynamicRuntimeType;
     builder.push(new HDynamicType(type, new TypeMask.exact(cls, classWorld)));
   }
 }