Store offset between fixed typed array base and data start in object

src/x64/lithium-codegen-x64.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_X64_LITHIUM_CODEGEN_X64_H_
 #define V8_X64_LITHIUM_CODEGEN_X64_H_
 
 #include "src/x64/lithium-x64.h"
 
 #include "src/base/logging.h"
@@ skipping 44 matching lines @@
         info()->requires_frame();
   }
   bool NeedsDeferredFrame() const {
     return !NeedsEagerFrame() && info()->is_deferred_calling();
   }
 
   // Support for converting LOperands to assembler types.
   Register ToRegister(LOperand* op) const;
   XMMRegister ToDoubleRegister(LOperand* op) const;
   bool IsInteger32Constant(LConstantOperand* op) const;
+  bool IsExternalConstant(LConstantOperand* op) const;
   bool IsDehoistedKeyConstant(LConstantOperand* op) const;
   bool IsSmiConstant(LConstantOperand* op) const;
   int32_t ToRepresentation(LConstantOperand* op, const Representation& r) const;
   int32_t ToInteger32(LConstantOperand* op) const;
   Smi* ToSmi(LConstantOperand* op) const;
   double ToDouble(LConstantOperand* op) const;
   ExternalReference ToExternalReference(LConstantOperand* op) const;
   Handle<Object> ToHandle(LConstantOperand* op) const;
   Operand ToOperand(LOperand* op) const;
 
@@ skipping 314 matching lines @@
   Label entry_;
   Label exit_;
   Label done_;
   Label* external_exit_;
   int instruction_index_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_LITHIUM_CODEGEN_X64_H_