[heap] Buffer counter updates for new space evacuation.

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/heap/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/scopeinfo.h"
 #include "src/base/bits.h"
@@ skipping 146 matching lines @@
       current_gc_flags_(Heap::kNoGCFlags),
       current_gc_callback_flags_(GCCallbackFlags::kNoGCCallbackFlags),
       external_string_table_(this),
       chunks_queued_for_free_(NULL),
       concurrent_unmapping_tasks_active_(0),
       pending_unmapping_tasks_semaphore_(0),
       gc_callbacks_depth_(0),
       deserialization_complete_(false),
       strong_roots_list_(NULL),
       array_buffer_tracker_(NULL),
+      heap_iterator_depth_(0),
       force_oom_(false) {
 // Allow build-time customization of the max semispace size. Building
 // V8 with snapshots and a non-default max semispace size is much
 // easier if you can define it as part of the build environment.
 #if defined(V8_MAX_SEMISPACE_SIZE)
   max_semi_space_size_ = reserved_semispace_size_ = V8_MAX_SEMISPACE_SIZE;
 #endif
 
   // Ensure old_generation_size_ is a multiple of kPageSize.
   DCHECK((max_old_generation_size_ & (Page::kPageSize - 1)) == 0);
@@ skipping 2917 matching lines @@
   // (1) the object is not in old space,
   // (2) the page of the object was already swept,
   // (3) the page was already concurrently swept. This case is an optimization
   // for concurrent sweeping. The WasSwept predicate for concurrently swept
   // pages is set after sweeping all pages.
   return !InOldSpace(address) || page->WasSwept() || page->SweepingCompleted();
 }
 
 
 void Heap::AdjustLiveBytes(HeapObject* object, int by, InvocationMode mode) {
-  if (incremental_marking()->IsMarking() &&
+  // As long as the inspected object is black and we are currently not iterating
+  // the heap using HeapIterator, we can update the live byte count. We cannot
+  // update while using HeapIterator because the iterator is temporarily
+  // marking the whole object graph, without updating live bytes.
+  if (!in_heap_iterator() &&
       Marking::IsBlack(Marking::MarkBitFrom(object->address()))) {
     if (mode == SEQUENTIAL_TO_SWEEPER) {
       MemoryChunk::IncrementLiveBytesFromGC(object, by);
     } else {
       MemoryChunk::IncrementLiveBytesFromMutator(object, by);
     }
   }
 }
 
 
@@ skipping 2536 matching lines @@
 
 HeapIterator::HeapIterator(Heap* heap,
                            HeapIterator::HeapObjectsFiltering filtering)
     : make_heap_iterable_helper_(heap),
       no_heap_allocation_(),
       heap_(heap),
       filtering_(filtering),
       filter_(nullptr),
       space_iterator_(nullptr),
       object_iterator_(nullptr) {
+  heap_->heap_iterator_start();
   // Start the iteration.
   space_iterator_ = new SpaceIterator(heap_);
   switch (filtering_) {
     case kFilterUnreachable:
       filter_ = new UnreachableObjectsFilter(heap_);
       break;
     default:
       break;
   }
   object_iterator_ = space_iterator_->next();
 }
 
 
 HeapIterator::~HeapIterator() {
+  heap_->heap_iterator_end();
 #ifdef DEBUG
   // Assert that in filtering mode we have iterated through all
   // objects. Otherwise, heap will be left in an inconsistent state.
   if (filtering_ != kNoFiltering) {
     DCHECK(object_iterator_ == nullptr);
   }
 #endif
   // Make sure the last iterator is deallocated.
   delete object_iterator_;
   delete space_iterator_;
@@ skipping 536 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8