Disable hoisting CheckClass due to excessive deoptimization.

runtime/vm/intermediate_language.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_INTERMEDIATE_LANGUAGE_H_
 #define VM_INTERMEDIATE_LANGUAGE_H_
 
 #include "vm/allocation.h"
 #include "vm/ast.h"
 #include "vm/growable_array.h"
@@ skipping 6775 matching lines @@
 
   bool IsNullCheck() const;
 
   virtual bool AllowsCSE() const { return true; }
   virtual EffectSet Effects() const { return EffectSet::None(); }
   virtual EffectSet Dependencies() const;
   virtual bool AttributesEqual(Instruction* other) const;
 
   virtual bool MayThrow() const { return false; }
 
+  void set_licm_hoisted(bool value) { licm_hoisted_ = value; }
+
  private:
   const ICData& unary_checks_;
+  bool licm_hoisted_;
 
   DISALLOW_COPY_AND_ASSIGN(CheckClassInstr);
 };
 
 
 class CheckSmiInstr : public TemplateInstruction<1> {
  public:
   CheckSmiInstr(Value* value, intptr_t original_deopt_id) {
     ASSERT(original_deopt_id != Isolate::kNoDeoptId);
     SetInputAt(0, value);
@@ skipping 285 matching lines @@
   ForwardInstructionIterator* current_iterator_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FlowGraphVisitor);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_