[heap] Remove unused flag prohibiting local slot buffer entries

src/heap/mark-compact.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.
 
 #include "src/heap/mark-compact.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/sys-info.h"
 #include "src/code-stubs.h"
@@ skipping 44 matching lines @@
       marking_parity_(ODD_MARKING_PARITY),
       was_marked_incrementally_(false),
       evacuation_(false),
       heap_(heap),
       marking_deque_memory_(NULL),
       marking_deque_memory_committed_(0),
       code_flusher_(nullptr),
       have_code_to_deoptimize_(false),
       compacting_(false),
       sweeping_in_progress_(false),
-      compaction_in_progress_(false),
       pending_sweeper_tasks_semaphore_(0),
       pending_compaction_tasks_semaphore_(0) {
 }
 
 #ifdef VERIFY_HEAP
 class VerifyMarkingVisitor : public ObjectVisitor {
  public:
   explicit VerifyMarkingVisitor(Heap* heap) : heap_(heap) {}
 
   void VisitPointers(Object** start, Object** end) override {
@@ skipping 2429 matching lines @@
   }
   heap()->set_encountered_transition_arrays(Smi::FromInt(0));
 }
 
 void MarkCompactCollector::RecordMigratedSlot(
     Object* value, Address slot, LocalSlotsBuffer* old_to_old_slots,
     LocalSlotsBuffer* old_to_new_slots) {
   // When parallel compaction is in progress, store and slots buffer entries
   // require synchronization.
   if (heap_->InNewSpace(value)) {
-    if (compaction_in_progress_) {
-      old_to_new_slots->Record(slot);
-    } else {
-      Page* page = Page::FromAddress(slot);
-      RememberedSet<OLD_TO_NEW>::Insert(page, slot);
-    }
+    old_to_new_slots->Record(slot);
   } else if (value->IsHeapObject() && IsOnEvacuationCandidate(value)) {
     old_to_old_slots->Record(slot);
   }
 }
 
 static inline SlotType SlotTypeForRMode(RelocInfo::Mode rmode) {
   if (RelocInfo::IsCodeTarget(rmode)) {
     return CODE_TARGET_SLOT;
   } else if (RelocInfo::IsCell(rmode)) {
     return CELL_TARGET_SLOT;
@@ skipping 1328 matching lines @@
     MarkBit mark_bit = Marking::MarkBitFrom(host);
     if (Marking::IsBlack(mark_bit)) {
       RelocInfo rinfo(isolate(), pc, RelocInfo::CODE_TARGET, 0, host);
       RecordRelocSlot(host, &rinfo, target);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8