[heap] Minor MC: Add marking

test/cctest/heap/heap-utils.cc

 // Copyright 2016 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 "test/cctest/heap/heap-utils.h"
 
 #include "src/factory.h"
 #include "src/heap/heap-inl.h"
 #include "src/heap/incremental-marking.h"
 #include "src/heap/mark-compact.h"
@@ skipping 124 matching lines @@
 }
 
 void SimulateFullSpace(v8::internal::NewSpace* space,
                        std::vector<Handle<FixedArray>>* out_handles) {
   heap::FillCurrentPage(space, out_handles);
   while (heap::FillUpOnePage(space, out_handles) || space->AddFreshPage()) {
   }
 }
 
 void SimulateIncrementalMarking(i::Heap* heap, bool force_completion) {
+  CHECK(FLAG_incremental_marking);
   i::IncrementalMarking* marking = heap->incremental_marking();
   i::MarkCompactCollector* collector = heap->mark_compact_collector();
   if (collector->sweeping_in_progress()) {
     collector->EnsureSweepingCompleted();
   }
   if (marking->IsSweeping()) {
     marking->FinalizeSweeping();
   }
   CHECK(marking->IsMarking() || marking->IsStopped() || marking->IsComplete());
   if (marking->IsStopped()) {
@@ skipping 48 matching lines @@
     int remaining = static_cast<int>(limit - top);
     space->heap()->CreateFillerObjectAt(top, remaining,
                                         ClearRecordedSlots::kNo);
     space->SetTopAndLimit(nullptr, nullptr);
   }
 }
 
 }  // namespace heap
 }  // namespace internal
 }  // namespace v8