[heap] Set progress bar flag for FixedArray upon allocation

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 168 matching lines @@
     StaticMarkingVisitor<IncrementalMarkingMarkingVisitor>::Initialize();
     table_.Register(kVisitFixedArray, &VisitFixedArrayIncremental);
     table_.Register(kVisitNativeContext, &VisitNativeContextIncremental);
     table_.Register(kVisitJSRegExp, &VisitJSRegExp);
   }
 
   static const int kProgressBarScanningChunk = 32 * 1024;
 
   static void VisitFixedArrayIncremental(Map* map, HeapObject* object) {
     MemoryChunk* chunk = MemoryChunk::FromAddress(object->address());
-    // TODO(mstarzinger): Move setting of the flag to the allocation site of
-    // the array. The visitor should just check the flag.
-    if (FLAG_use_marking_progress_bar &&

[Hannes Payer (out of office), 2016/09/30 10:32:41]

Let's make that a DCHECK.

[Michael Lippautz, 2016/09/30 10:36:14]

Done.

-        chunk->owner()->identity() == LO_SPACE) {
-      chunk->SetFlag(MemoryChunk::HAS_PROGRESS_BAR);
-    }
     if (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR)) {
       Heap* heap = map->GetHeap();
       // When using a progress bar for large fixed arrays, scan only a chunk of
       // the array and try to push it onto the marking deque again until it is
       // fully scanned. Fall back to scanning it through to the end in case this
       // fails because of a full deque.
       int object_size = FixedArray::BodyDescriptor::SizeOf(map, object);
       int start_offset =
           Max(FixedArray::BodyDescriptor::kStartOffset, chunk->progress_bar());
       int end_offset =
@@ skipping 996 matching lines @@
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 
 }  // namespace internal
 }  // namespace v8