Insert explicit deoptimization for named loads that have "uninitialized" type feedback.

src/hydrogen.cc

 // Copyright 2012 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 4505 matching lines @@
   } else {
     // Non-negative property indices are in the properties array.
     int offset = (index * kPointerSize) + FixedArray::kHeaderSize;
     return new(zone()) HLoadNamedField(object, false, offset);
   }
 }
 
 
 HInstruction* HGraphBuilder::BuildLoadNamedGeneric(HValue* obj,
                                                    Property* expr) {
+  if (expr->IsUninitialized()) {
+    AddInstruction(new(zone()) HSoftDeoptimize);
+    current_block()->MarkAsDeoptimizing();
+  }
   ASSERT(expr->key()->IsPropertyName());
   Handle<Object> name = expr->key()->AsLiteral()->handle();
   HValue* context = environment()->LookupContext();
   return new(zone()) HLoadNamedGeneric(context, obj, name);
 }
 
 
 HInstruction* HGraphBuilder::BuildLoadNamed(HValue* obj,
                                             Property* expr,
                                             Handle<Map> map,
@@ skipping 3625 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal