Introduce LiteralsArray to hide it's implementation.

src/full-codegen/x64/full-codegen-x64.cc

 // 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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/compiler.h"
@@ skipping 1435 matching lines @@
 void FullCodeGenerator::VisitRegExpLiteral(RegExpLiteral* expr) {
   Comment cmnt(masm_, "[ RegExpLiteral");
   Label materialized;
   // Registers will be used as follows:
   // rdi = JS function.
   // rcx = literals array.
   // rbx = regexp literal.
   // rax = regexp literal clone.
   __ movp(rdi, Operand(rbp, JavaScriptFrameConstants::kFunctionOffset));
   __ movp(rcx, FieldOperand(rdi, JSFunction::kLiteralsOffset));
-  int literal_offset =
-      FixedArray::kHeaderSize + expr->literal_index() * kPointerSize;
+  int literal_offset = LiteralsArray::OffsetOfLiteralAt(expr->literal_index());
   __ movp(rbx, FieldOperand(rcx, literal_offset));
   __ CompareRoot(rbx, Heap::kUndefinedValueRootIndex);
   __ j(not_equal, &materialized, Label::kNear);
 
   // Create regexp literal using runtime function
   // Result will be in rax.
   __ Push(rcx);
   __ Push(Smi::FromInt(expr->literal_index()));
   __ Push(expr->pattern());
   __ Push(expr->flags());
@@ skipping 3691 matching lines @@
             Assembler::target_address_at(call_target_address,
                                          unoptimized_code));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64