Fix the negative lookup stub to handle deleted entries in a

src/x64/code-stubs-x64.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 5735 matching lines @@
 void StringDictionaryLookupStub::GenerateNegativeLookup(MacroAssembler* masm,
                                                         Label* miss,
                                                         Label* done,
                                                         Register properties,
                                                         Handle<String> name,
                                                         Register r0) {
   // If names of slots in range from 1 to kProbes - 1 for the hash value are
   // not equal to the name and kProbes-th slot is not used (its name is the
   // undefined value), it guarantees the hash table doesn't contain the
   // property. It's true even if some slots represent deleted properties
-  // (their names are the null value).
+  // (their names are the hole value).
   for (int i = 0; i < kInlinedProbes; i++) {
     // r0 points to properties hash.
     // Compute the masked index: (hash + i + i * i) & mask.
     Register index = r0;
     // Capacity is smi 2^n.
     __ SmiToInteger32(index, FieldOperand(properties, kCapacityOffset));
     __ decl(index);
     __ and_(index,
             Immediate(name->Hash() + StringDictionary::GetProbeOffset(i)));
 
     // Scale the index by multiplying by the entry size.
     ASSERT(StringDictionary::kEntrySize == 3);
     __ lea(index, Operand(index, index, times_2, 0));  // index *= 3.
 
     Register entity_name = r0;
     // Having undefined at this place means the name is not contained.
     ASSERT_EQ(kSmiTagSize, 1);
     __ movq(entity_name, Operand(properties,
                                  index,
                                  times_pointer_size,
                                  kElementsStartOffset - kHeapObjectTag));
     __ Cmp(entity_name, masm->isolate()->factory()->undefined_value());
     __ j(equal, done);
 
     // Stop if found the property.
     __ Cmp(entity_name, Handle<String>(name));
     __ j(equal, miss);
 
+    Label the_hole;
+    // Check for the hole and skip.
+    __ CompareRoot(entity_name, Heap::kTheHoleValueRootIndex);
+    __ j(equal, &the_hole, Label::kNear);
+
     // Check if the entry name is not a symbol.
     __ movq(entity_name, FieldOperand(entity_name, HeapObject::kMapOffset));
     __ testb(FieldOperand(entity_name, Map::kInstanceTypeOffset),
              Immediate(kIsSymbolMask));
     __ j(zero, miss);
+
+    __ bind(&the_hole);
   }
 
   StringDictionaryLookupStub stub(properties,
                                   r0,
                                   r0,
                                   StringDictionaryLookupStub::NEGATIVE_LOOKUP);
   __ Push(Handle<Object>(name));
   __ push(Immediate(name->Hash()));
   __ CallStub(&stub);
   __ testq(r0, r0);
@@ skipping 505 matching lines @@
                                  xmm0,
                                  &slow_elements);
   __ ret(0);
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64