MIPS: Fix r19360 "Improve positions tracking inside the HGraphBuilder."

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 830 matching lines @@
   }
   block->set_argument_count(argument_count_);
   next_block_ = NULL;
   current_block_ = NULL;
 }
 
 
 void LChunkBuilder::VisitInstruction(HInstruction* current) {
   HInstruction* old_current = current_instruction_;
   current_instruction_ = current;
-  if (current->has_position()) position_ = current->position();
 
   LInstruction* instr = NULL;
   if (current->CanReplaceWithDummyUses()) {
     if (current->OperandCount() == 0) {
       instr = DefineAsRegister(new(zone()) LDummy());
     } else {
       ASSERT(!current->OperandAt(0)->IsControlInstruction());
       instr = DefineAsRegister(new(zone())
           LDummyUse(UseAny(current->OperandAt(0))));
     }
@@ skipping 1537 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