Support elements transitions in load elimination

src/hydrogen-load-elimination.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 80 matching lines @@
                s->object()->ActualValue()->id(),
                s->value()->id()));
         HValue* result = store(s);
         if (result == NULL) {
           // The store is redundant. Remove it.
           TRACE(("  remove S%d\n", instr->id()));
           instr->DeleteAndReplaceWith(NULL);
         }
         break;
       }
+      case HValue::kTransitionElementsKind: {
+        HTransitionElementsKind* t = HTransitionElementsKind::cast(instr);
+        HValue* object = t->object()->ActualValue();
+        KillFieldInternal(object, FieldOf(JSArray::kElementsOffset), NULL);
+        KillFieldInternal(object, FieldOf(JSObject::kMapOffset), NULL);
+        break;
+      }
       default: {
         if (instr->CheckChangesFlag(kInobjectFields)) {
           TRACE((" kill-all i%d\n", instr->id()));
           Kill();
           break;
         }
         if (instr->CheckChangesFlag(kMaps)) {
           TRACE((" kill-maps i%d\n", instr->id()));
           KillOffset(JSObject::kMapOffset);
         }
@@ skipping 408 matching lines @@
   } else {
     // Perform only local analysis.
     for (int i = 0; i < graph()->blocks()->length(); i++) {
       table->Kill();
       engine.AnalyzeOneBlock(graph()->blocks()->at(i), table);
     }
   }
 }
 
 } }  // namespace v8::internal