Correct handling of arrays with callbacks in the prototype chain.

src/ia32/macro-assembler-ia32.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 3532 matching lines @@
       JSArray::kSize + AllocationMemento::kSize - kHeapObjectTag));
   cmp(scratch_reg, Immediate(new_space_start));
   j(less, no_memento_found);
   cmp(scratch_reg, Operand::StaticVariable(new_space_allocation_top));
   j(greater, no_memento_found);
   cmp(MemOperand(scratch_reg, -AllocationMemento::kSize),
       Immediate(isolate()->factory()->allocation_memento_map()));
 }
 
 
+void MacroAssembler::JumpIfDictionaryInPrototypeChain(
+    Register object,
+    Register scratch0,
+    Register scratch1,
+    Label* found) {
+  ASSERT(!scratch1.is(scratch0));
+  Factory* factory = isolate()->factory();
+  Register current = scratch0;
+  Label loop_again;
+
+  // scratch contained elements pointer.
+  mov(current, object);
+
+  // Loop based on the map going up the prototype chain.
+  bind(&loop_again);
+  mov(current, FieldOperand(current, HeapObject::kMapOffset));
+  mov(scratch1, FieldOperand(current, Map::kBitField2Offset));
+  and_(scratch1, Map::kElementsKindMask);
+  shr(scratch1, Map::kElementsKindShift);
+  cmp(scratch1, Immediate(DICTIONARY_ELEMENTS));
+  j(equal, found);
+  mov(current, FieldOperand(current, Map::kPrototypeOffset));
+  cmp(current, Immediate(factory->null_value()));
+  j(not_equal, &loop_again);
+}
+
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32