[heap] Start concurrent marking simultaneously with incremental marking.

src/heap/incremental-marking.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/incremental-marking.h"
 
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
 #include "src/conversions.h"
+#include "src/heap/concurrent-marking.h"
 #include "src/heap/gc-idle-time-handler.h"
 #include "src/heap/gc-tracer.h"
 #include "src/heap/heap-inl.h"
 #include "src/heap/mark-compact-inl.h"
 #include "src/heap/object-stats.h"
 #include "src/heap/objects-visiting-inl.h"
 #include "src/heap/objects-visiting.h"
 #include "src/tracing/trace-event.h"
 #include "src/v8.h"
 
@@ skipping 518 matching lines @@
   }
 #endif
 
   heap_->CompletelyClearInstanceofCache();
   heap_->isolate()->compilation_cache()->MarkCompactPrologue();
 
   // Mark strong roots grey.
   IncrementalMarkingRootMarkingVisitor visitor(this);
   heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG);
 
+  if (FLAG_concurrent_marking) {
+    ConcurrentMarking* concurrent_marking = heap_->concurrent_marking();
+    heap_->mark_compact_collector()->marking_deque()->Iterate(
+        [concurrent_marking](HeapObject* obj) {
+          concurrent_marking->AddRoot(obj);
+        });
+    concurrent_marking->StartTask();
+  }
+
   // Ready to start incremental marking.
   if (FLAG_trace_incremental_marking) {
     heap()->isolate()->PrintWithTimestamp("[IncrementalMarking] Running\n");
   }
 }
 
 void IncrementalMarking::StartBlackAllocation() {
   DCHECK(FLAG_black_allocation);
   DCHECK(IsMarking());
   black_allocation_ = true;
@@ skipping 616 matching lines @@
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 
 }  // namespace internal
 }  // namespace v8