Integrate concurrent sweeping with incremental marking.

src/incremental-marking.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 544 matching lines @@
     bool success = marking_deque_memory_->Uncommit(
         reinterpret_cast<Address>(marking_deque_memory_->address()),
         marking_deque_memory_->size());
     CHECK(success);
     marking_deque_memory_committed_ = false;
   }
 }
 
 
 void IncrementalMarking::Start() {
-  ASSERT(!heap_->mark_compact_collector()->IsConcurrentSweepingInProgress());
   if (FLAG_trace_incremental_marking) {
     PrintF("[IncrementalMarking] Start\n");
   }
   ASSERT(FLAG_incremental_marking);
   ASSERT(state_ == STOPPED);
 
   ResetStepCounters();
 
   if (heap_->IsSweepingComplete()) {
     StartMarking(ALLOW_COMPACTION);
@@ skipping 318 matching lines @@
   bytes_scanned_ += bytes_to_process;
 
   double start = 0;
 
   if (FLAG_trace_incremental_marking || FLAG_trace_gc ||
       FLAG_print_cumulative_gc_stat) {
     start = OS::TimeCurrentMillis();
   }
 
   if (state_ == SWEEPING) {
-    if (heap_->AdvanceSweepers(static_cast<int>(bytes_to_process))) {
+    if (heap_->EnsureSweepersProgressed(static_cast<int>(bytes_to_process))) {
       bytes_scanned_ = 0;
       StartMarking(PREVENT_COMPACTION);
     }
   } else if (state_ == MARKING) {
     ProcessMarkingDeque(bytes_to_process);
     if (marking_deque_.IsEmpty()) MarkingComplete(action);
   }
 
   steps_count_++;
   steps_count_since_last_gc_++;
@@ skipping 88 matching lines @@
   bytes_scanned_ = 0;
   write_barriers_invoked_since_last_step_ = 0;
 }
 
 
 int64_t IncrementalMarking::SpaceLeftInOldSpace() {
   return heap_->MaxOldGenerationSize() - heap_->PromotedSpaceSizeOfObjects();
 }
 
 } }  // namespace v8::internal