PPC: Introduce LiteralsArray to hide it's implementation.

src/full-codegen/ppc/full-codegen-ppc.cc

 // Copyright 2014 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_PPC
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/compiler.h"
@@ skipping 1451 matching lines @@
   Label materialized;
   // Registers will be used as follows:
   // r8 = materialized value (RegExp literal)
   // r7 = JS function, literals array
   // r6 = literal index
   // r5 = RegExp pattern
   // r4 = RegExp flags
   // r3 = RegExp literal clone
   __ LoadP(r3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
   __ LoadP(r7, FieldMemOperand(r3, JSFunction::kLiteralsOffset));
-  int literal_offset =
-      FixedArray::kHeaderSize + expr->literal_index() * kPointerSize;
+  int literal_offset = LiteralsArray::OffsetOfLiteralAt(expr->literal_index());
   __ LoadP(r8, FieldMemOperand(r7, literal_offset), r0);
   __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
   __ cmp(r8, ip);
   __ bne(&materialized);
 
   // Create regexp literal using runtime function.
   // Result will be in r3.
   __ LoadSmiLiteral(r6, Smi::FromInt(expr->literal_index()));
   __ mov(r5, Operand(expr->pattern()));
   __ mov(r4, Operand(expr->flags()));
@@ skipping 3739 matching lines @@
     return ON_STACK_REPLACEMENT;
   }
 
   DCHECK(interrupt_address ==
          isolate->builtins()->OsrAfterStackCheck()->entry());
   return OSR_AFTER_STACK_CHECK;
 }
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_PPC