PPC: [stubs] Optimize LoadGlobalViaContextStub and StoreGlobalViaContextStub.

src/ppc/macro-assembler-ppc.h

 // 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.
 
 #ifndef V8_PPC_MACRO_ASSEMBLER_PPC_H_
 #define V8_PPC_MACRO_ASSEMBLER_PPC_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 195 matching lines @@
 
   // Detects conservatively whether an object is data-only, i.e. it does need to
   // be scanned by the garbage collector.
   void JumpIfDataObject(Register value, Register scratch,
                         Label* not_data_object);
 
   // Notify the garbage collector that we wrote a pointer into an object.
   // |object| is the object being stored into, |value| is the object being
   // stored.  value and scratch registers are clobbered by the operation.
   // The offset is the offset from the start of the object, not the offset from
-  // the tagged HeapObject pointer.  For use with FieldOperand(reg, off).
+  // the tagged HeapObject pointer.  For use with FieldMemOperand(reg, off).
   void RecordWriteField(
       Register object, int offset, Register value, Register scratch,
       LinkRegisterStatus lr_status, SaveFPRegsMode save_fp,
       RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
       SmiCheck smi_check = INLINE_SMI_CHECK,
       PointersToHereCheck pointers_to_here_check_for_value =
           kPointersToHereMaybeInteresting);
 
   // As above, but the offset has the tag presubtracted.  For use with
   // MemOperand(reg, off).
@@ skipping 1315 matching lines @@
   byte* address_;            // The address of the code being patched.
   int size_;                 // Number of bytes of the expected patch size.
   MacroAssembler masm_;      // Macro assembler used to generate the code.
   FlushICache flush_cache_;  // Whether to flush the I cache after patching.
 };
 
 
 // -----------------------------------------------------------------------------
 // Static helper functions.
 
-inline MemOperand ContextOperand(Register context, int index) {
+inline MemOperand ContextOperand(Register context, int index = 0) {
   return MemOperand(context, Context::SlotOffset(index));
 }
 
 
 inline MemOperand GlobalObjectOperand() {
   return ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX);
 }
 
 
 #ifdef GENERATED_CODE_COVERAGE
 #define CODE_COVERAGE_STRINGIFY(x) #x
 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm)    \
   masm->stop(__FILE_LINE__); \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 }
 }  // namespace v8::internal
 
 #endif  // V8_PPC_MACRO_ASSEMBLER_PPC_H_