[heap] Remove dead write write barrier counter code

src/mips64/code-stubs-mips64.cc

 // Copyright 2012 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.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/code-stubs.h"
 #include "src/api-arguments.h"
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 3168 matching lines @@
 
 
 void RecordWriteStub::CheckNeedsToInformIncrementalMarker(
     MacroAssembler* masm,
     OnNoNeedToInformIncrementalMarker on_no_need,
     Mode mode) {
   Label on_black;
   Label need_incremental;
   Label need_incremental_pop_scratch;
 
-  __ And(regs_.scratch0(), regs_.object(), Operand(~Page::kPageAlignmentMask));
-  __ ld(regs_.scratch1(),
-        MemOperand(regs_.scratch0(),
-                   MemoryChunk::kWriteBarrierCounterOffset));
-  __ Dsubu(regs_.scratch1(), regs_.scratch1(), Operand(1));
-  __ sd(regs_.scratch1(),
-         MemOperand(regs_.scratch0(),
-                    MemoryChunk::kWriteBarrierCounterOffset));
-  __ Branch(&need_incremental, lt, regs_.scratch1(), Operand(zero_reg));
-
   // Let's look at the color of the object:  If it is not black we don't have
   // to inform the incremental marker.
   __ JumpIfBlack(regs_.object(), regs_.scratch0(), regs_.scratch1(), &on_black);
 
   regs_.Restore(masm);
   if (on_no_need == kUpdateRememberedSetOnNoNeedToInformIncrementalMarker) {
     __ RememberedSetHelper(object(),
                            address(),
                            value(),
                            save_fp_regs_mode(),
@@ skipping 1928 matching lines @@
                            kStackUnwindSpace, kInvalidStackOffset,
                            return_value_operand, NULL);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64