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runtime/vm/flow_graph_optimizer.cc

 // 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.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/cpu.h"
 #include "vm/dart_entry.h"
@@ skipping 4432 matching lines @@
     StoreInstanceFieldInstr* instr) {
   if (instr->IsUnboxedStore()) {
     ASSERT(instr->is_initialization_);
     // Determine if this field should be unboxed based on the usage of getter
     // and setter functions: The heuristic requires that the setter has a
     // usage count of at least 1/kGetterSetterRatio of the getter usage count.
     // This is to avoid unboxing fields where the setter is never or rarely
     // executed.
     const Field& field = Field::ZoneHandle(I, instr->field().raw());
     const String& field_name = String::Handle(I, field.name());
-    class Class& owner = Class::Handle(I, field.owner());
+    const Class& owner = Class::Handle(I, field.owner());
     const Function& getter =
         Function::Handle(I, owner.LookupGetterFunction(field_name));
     const Function& setter =
         Function::Handle(I, owner.LookupSetterFunction(field_name));
     bool result = !getter.IsNull()
                && !setter.IsNull()
                && (setter.usage_counter() > 0)
                && (FLAG_getter_setter_ratio * setter.usage_counter() >=
                    getter.usage_counter());
     if (!result) {
@@ skipping 5151 matching lines @@
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits_collector_.exits().length(); i++) {
     CreateMaterializationAt(
         exits_collector_.exits()[i], alloc, alloc->cls(), *slots);
   }
 }
 
 
 }  // namespace dart