[heap] Report wrappers after processing the marking deque incrementally

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/gc-idle-time-handler.h"
@@ skipping 874 matching lines @@
              Marking::IsWhite(ObjectMarking::MarkBitFrom(obj)));
       continue;
     }
 
     Map* map = obj->map();
     int size = obj->SizeFromMap(map);
     unscanned_bytes_of_large_object_ = 0;
     VisitObject(map, obj, size);
     bytes_processed += size - unscanned_bytes_of_large_object_;
   }
+  // Report all found wrappers to the embedder. This is necessary as the
+  // embedder could potentially invalidate wrappers as soon as V8 is done
+  // with its incremental marking processing. Any cached wrappers could
+  // result in broken pointers at this point.
+  heap_->local_embedder_heap_tracer()->RegisterWrappersWithRemoteTracer();
   return bytes_processed;
 }
 
 
 void IncrementalMarking::Hurry() {
   // A scavenge may have pushed new objects on the marking deque (due to black
   // allocation) even in COMPLETE state. This may happen if scavenges are
   // forced e.g. in tests. It should not happen when COMPLETE was set when
   // incremental marking finished and a regular GC was triggered after that
   // because should_hurry_ will force a full GC.
@@ skipping 121 matching lines @@
 }
 
 double IncrementalMarking::AdvanceIncrementalMarking(
     double deadline_in_ms, CompletionAction completion_action,
     ForceCompletionAction force_completion, StepOrigin step_origin) {
   HistogramTimerScope incremental_marking_scope(
       heap_->isolate()->counters()->gc_incremental_marking());
   TRACE_EVENT0("v8", "V8.GCIncrementalMarking");
   TRACE_GC(heap_->tracer(), GCTracer::Scope::MC_INCREMENTAL);
   DCHECK(!IsStopped());
+  DCHECK_EQ(
+      0, heap_->local_embedder_heap_tracer()->NumberOfCachedWrappersToTrace());
 
   double remaining_time_in_ms = 0.0;
   intptr_t step_size_in_bytes = GCIdleTimeHandler::EstimateMarkingStepSize(
       kStepSizeInMs,
       heap()->tracer()->IncrementalMarkingSpeedInBytesPerMillisecond());
 
   const bool incremental_wrapper_tracing =
       state_ == MARKING && FLAG_incremental_marking_wrappers &&
       heap_->local_embedder_heap_tracer()->InUse();
   do {
@@ skipping 161 matching lines @@
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 
 }  // namespace internal
 }  // namespace v8