Repeatedly overapproximate the weak closure as long as we make progress

src/heap/heap.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/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/base/bits.h"
 #include "src/base/once.h"
@@ skipping 748 matching lines @@
   DCHECK(!incremental_marking()->weak_closure_was_overapproximated());
   OverApproximateWeakClosure("GC interrupt");
 }
 
 
 void Heap::OverApproximateWeakClosure(const char* gc_reason) {
   if (FLAG_trace_incremental_marking) {
     PrintF("[IncrementalMarking] Overapproximate weak closure (%s).\n",
            gc_reason);
   }
+
+  GCTracer::Scope gc_scope(tracer(),
+                           GCTracer::Scope::MC_INCREMENTAL_WEAKCLOSURE);
+
   {
     GCCallbacksScope scope(this);
     if (scope.CheckReenter()) {
       AllowHeapAllocation allow_allocation;
       GCTracer::Scope scope(tracer(), GCTracer::Scope::EXTERNAL);
       VMState<EXTERNAL> state(isolate_);
       HandleScope handle_scope(isolate_);
       CallGCPrologueCallbacks(kGCTypeMarkSweepCompact, kNoGCCallbackFlags);
     }
   }
@@ skipping 5799 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 }
 }  // namespace v8::internal