[stubs] Optimize LoadGlobalViaContextStub and StoreGlobalViaContextStub.

src/arm64/macro-assembler-arm64.h

 // Copyright 2013 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_ARM64_MACRO_ASSEMBLER_ARM64_H_
 #define V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
 
 #include <vector>
 
 #include "src/bailout-reason.h"
@@ skipping 1751 matching lines @@
 
   void JumpIfInNewSpace(Register object,
                         Label* branch) {
     InNewSpace(object, eq, branch);
   }
 
   // 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 =
@@ skipping 443 matching lines @@
   // Available scratch registers.
   CPURegList* available_;     // kRegister
   CPURegList* availablefp_;   // kFPRegister
 
   // The state of the available lists at the start of this scope.
   RegList old_available_;     // kRegister
   RegList old_availablefp_;   // kFPRegister
 };
 
 
-inline MemOperand ContextMemOperand(Register context, int index) {
+inline MemOperand ContextMemOperand(Register context, int index = 0) {
   return MemOperand(context, Context::SlotOffset(index));
 }
 
 inline MemOperand GlobalObjectMemOperand() {
   return ContextMemOperand(cp, Context::GLOBAL_OBJECT_INDEX);
 }
 
 
 // Encode and decode information about patchable inline SMI checks.
 class InlineSmiCheckInfo {
@@ skipping 49 matching lines @@
 #error "Unsupported option"
 #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
 
 #endif  // V8_ARM64_MACRO_ASSEMBLER_ARM64_H_