Box values of LoadCodeUnits that fall outside of smi range on 32bit platforms.

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 4600 matching lines @@
                                        new Value(flow_graph_->constant_null()),
                                        kNoStoreBarrier,
                                        instr->token_pos());
     store->set_is_initialization(true);  // Won't be eliminated by DSE.
     flow_graph_->InsertAfter(cursor, store, NULL, FlowGraph::kEffect);
     cursor = store;
   }
 }
 
 
+void FlowGraphOptimizer::VisitLoadCodeUnits(LoadCodeUnitsInstr* instr) {
+  // TODO(zerny): Use kUnboxedUint32 once it is fully supported/optimized.
+#if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_ARM)
+  if (!instr->can_pack_into_smi())
+    instr->set_representation(kUnboxedMint);
+#endif
+}
+
+
 bool FlowGraphOptimizer::TryInlineInstanceSetter(InstanceCallInstr* instr,
                                                  const ICData& unary_ic_data) {
   ASSERT((unary_ic_data.NumberOfChecks() > 0) &&
       (unary_ic_data.NumArgsTested() == 1));
   if (FLAG_enable_type_checks) {
     // Checked mode setters are inlined like normal methods by conventional
     // inlining.
     return false;
   }
 
@@ skipping 5409 matching lines @@
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits_collector_.exits().length(); i++) {
     CreateMaterializationAt(
         exits_collector_.exits()[i], alloc, *slots);
   }
 }
 
 
 }  // namespace dart