A64: Port recent ARM optimizations in LCodeGen::DoAccessArgumentsAt.

src/a64/lithium-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 794 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoBoundsCheckBaseIndexInformation(
     HBoundsCheckBaseIndexInformation* instr) {
   UNREACHABLE();
   return NULL;
 }
 
 
 LInstruction* LChunkBuilder::DoAccessArgumentsAt(HAccessArgumentsAt* instr) {
-  // TODO(all): Try to improve this, like ARM r17925.
   info()->MarkAsRequiresFrame();
   LOperand* args = NULL;
   LOperand* length = NULL;
   LOperand* index = NULL;
-  LOperand* temp = NULL;
 
   if (instr->length()->IsConstant() && instr->index()->IsConstant()) {
     args = UseRegisterAtStart(instr->arguments());
     length = UseConstant(instr->length());
     index = UseConstant(instr->index());
   } else {
     args = UseRegister(instr->arguments());
     length = UseRegisterAtStart(instr->length());
     index = UseRegisterOrConstantAtStart(instr->index());
-    temp = TempRegister();
   }
 
-  return DefineAsRegister(
-      new(zone()) LAccessArgumentsAt(args, length, index, temp));
+  return DefineAsRegister(new(zone()) LAccessArgumentsAt(args, length, index));
 }
 
 
 LInstruction* LChunkBuilder::DoAdd(HAdd* instr) {
   if (instr->representation().IsSmiOrInteger32()) {
     ASSERT(instr->left()->representation().Equals(instr->representation()));
     ASSERT(instr->right()->representation().Equals(instr->representation()));
     LOperand* left = UseRegisterAtStart(instr->BetterLeftOperand());
     LOperand* right =
         UseRegisterOrConstantAtStart(instr->BetterRightOperand());
@@ skipping 1601 matching lines @@
 
 LInstruction* LChunkBuilder::DoWrapReceiver(HWrapReceiver* instr) {
   LOperand* receiver = UseRegister(instr->receiver());
   LOperand* function = UseRegister(instr->function());
   LWrapReceiver* result = new(zone()) LWrapReceiver(receiver, function);
   return AssignEnvironment(DefineAsRegister(result));
 }
 
 
 } }  // namespace v8::internal