MIPS: Optimize AccessArgumentsAt.

src/mips/lithium-mips.cc

 // Copyright 2012 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 2441 matching lines @@
   instr->ReplayEnvironment(current_block_->last_environment());
 
   // There are no real uses of a captured object.
   return NULL;
 }
 
 
 LInstruction* LChunkBuilder::DoAccessArgumentsAt(HAccessArgumentsAt* instr) {
   info()->MarkAsRequiresFrame();
   LOperand* args = UseRegister(instr->arguments());
-  LOperand* length;
-  LOperand* index;
-  if (instr->length()->IsConstant() && instr->index()->IsConstant()) {
-    length = UseRegisterOrConstant(instr->length());
-    index = UseOrConstant(instr->index());
-  } else {
-    length = UseTempRegister(instr->length());
-    index = UseRegisterAtStart(instr->index());
-  }
+  LOperand* length = UseRegisterOrConstantAtStart(instr->length());
+  LOperand* index = UseRegisterOrConstantAtStart(instr->index());
   return DefineAsRegister(new(zone()) LAccessArgumentsAt(args, length, index));
 }
 
 
 LInstruction* LChunkBuilder::DoToFastProperties(HToFastProperties* instr) {
   LOperand* object = UseFixed(instr->value(), a0);
   LToFastProperties* result = new(zone()) LToFastProperties(object);
   return MarkAsCall(DefineFixed(result, v0), instr);
 }
 
@@ skipping 114 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseRegister(instr->index());
   return DefineAsRegister(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal