Ensure that all descriptors have a valid enumeration index, and replace NextEnumIndex with LastAdde…

src/x64/lithium-codegen-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 4987 matching lines @@
   DeoptimizeIf(not_equal, instr->environment());
   __ bind(&use_cache);
 }
 
 
 void LCodeGen::DoForInCacheArray(LForInCacheArray* instr) {
   Register map = ToRegister(instr->map());
   Register result = ToRegister(instr->result());
   __ LoadInstanceDescriptors(map, result);
   __ movq(result,
-          FieldOperand(result, DescriptorArray::kEnumerationIndexOffset));
+          FieldOperand(result, DescriptorArray::kLastAddedOffset));
   __ movq(result,
           FieldOperand(result, FixedArray::SizeFor(instr->idx())));
   Condition cc = masm()->CheckSmi(result);
   DeoptimizeIf(cc, instr->environment());
 }
 
 
 void LCodeGen::DoCheckMapValue(LCheckMapValue* instr) {
   Register object = ToRegister(instr->value());
   __ cmpq(ToRegister(instr->map()),
@@ skipping 26 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64