Remove HFixedArrayBaseLength instruction and replace with regular HLoadNamedField.

src/x64/lithium-codegen-x64.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 1535 matching lines @@
   AllowDeferredHandleDereference smi_check;
   if (value->IsSmi()) {
     __ Move(ToRegister(instr->result()), value);
   } else {
     __ LoadHeapObject(ToRegister(instr->result()),
                       Handle<HeapObject>::cast(value));
   }
 }
 
 
-void LCodeGen::DoFixedArrayBaseLength(LFixedArrayBaseLength* instr) {
-  Register result = ToRegister(instr->result());
-  Register array = ToRegister(instr->value());
-  __ movq(result, FieldOperand(array, FixedArrayBase::kLengthOffset));
-}
-
-
 void LCodeGen::DoMapEnumLength(LMapEnumLength* instr) {
   Register result = ToRegister(instr->result());
   Register map = ToRegister(instr->value());
   __ EnumLength(result, map);
 }
 
 
 void LCodeGen::DoElementsKind(LElementsKind* instr) {
   Register result = ToRegister(instr->result());
   Register input = ToRegister(instr->value());
@@ skipping 4080 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64