}
+void MarkCompactCollector::PushBlack(HeapObject* obj) {
+ if (marking_deque_.PushBlack(obj)) {
+ MemoryChunk::IncrementLiveBytesFromGC(obj, obj->Size());
+ } else {
+ Marking::BlackToGrey(obj);
+ }
+}
+
+
+void MarkCompactCollector::UnshiftBlack(HeapObject* obj) {
+ if (!marking_deque_.UnshiftBlack(obj)) {
+ MemoryChunk::IncrementLiveBytesFromGC(obj, -obj->Size());
+ Marking::BlackToGrey(obj);
+ }
+}
+
+
void MarkCompactCollector::MarkObject(HeapObject* obj, MarkBit mark_bit) {
DCHECK(Marking::MarkBitFrom(obj) == mark_bit);
if (Marking::IsWhite(mark_bit)) {
Marking::WhiteToBlack(mark_bit);
- MemoryChunk::IncrementLiveBytesFromGC(obj, obj->Size());
DCHECK(obj->GetIsolate()->heap()->Contains(obj));
- marking_deque_.PushBlack(obj);
+ PushBlack(obj);
}
}
// iterator. Stop when the marking stack is filled or the end of the space
// is reached, whichever comes first.
template <class T>
-static void DiscoverGreyObjectsWithIterator(Heap* heap,
- MarkingDeque* marking_deque,
- T* it) {
+void MarkCompactCollector::DiscoverGreyObjectsWithIterator(T* it) {
// The caller should ensure that the marking stack is initially not full,
// so that we don't waste effort pointlessly scanning for objects.
- DCHECK(!marking_deque->IsFull());
+ DCHECK(!marking_deque()->IsFull());
- Map* filler_map = heap->one_pointer_filler_map();
+ Map* filler_map = heap()->one_pointer_filler_map();
for (HeapObject* object = it->Next(); object != NULL; object = it->Next()) {
MarkBit markbit = Marking::MarkBitFrom(object);
if ((object->map() != filler_map) && Marking::IsGrey(markbit)) {
Marking::GreyToBlack(markbit);
- MemoryChunk::IncrementLiveBytesFromGC(object, object->Size());
- marking_deque->PushBlack(object);
- if (marking_deque->IsFull()) return;
+ PushBlack(object);
+ if (marking_deque()->IsFull()) return;
}
}
}
static inline int MarkWordToObjectStarts(uint32_t mark_bits, int* starts);
-static void DiscoverGreyObjectsOnPage(MarkingDeque* marking_deque,
- MemoryChunk* p) {
- DCHECK(!marking_deque->IsFull());
+void MarkCompactCollector::DiscoverGreyObjectsOnPage(MemoryChunk* p) {
+ DCHECK(!marking_deque()->IsFull());
DCHECK(strcmp(Marking::kWhiteBitPattern, "00") == 0);
DCHECK(strcmp(Marking::kBlackBitPattern, "10") == 0);
DCHECK(strcmp(Marking::kGreyBitPattern, "11") == 0);
Marking::GreyToBlack(markbit);
Address addr = cell_base + offset * kPointerSize;
HeapObject* object = HeapObject::FromAddress(addr);
- MemoryChunk::IncrementLiveBytesFromGC(object, object->Size());
- marking_deque->PushBlack(object);
- if (marking_deque->IsFull()) return;
+ PushBlack(object);
+ if (marking_deque()->IsFull()) return;
offset += 2;
grey_objects >>= 2;
}
}
-static void DiscoverGreyObjectsInSpace(Heap* heap, MarkingDeque* marking_deque,
- PagedSpace* space) {
+void MarkCompactCollector::DiscoverGreyObjectsInSpace(PagedSpace* space) {
PageIterator it(space);
while (it.has_next()) {
Page* p = it.next();
- DiscoverGreyObjectsOnPage(marking_deque, p);
- if (marking_deque->IsFull()) return;
+ DiscoverGreyObjectsOnPage(p);
+ if (marking_deque()->IsFull()) return;
}
}
-static void DiscoverGreyObjectsInNewSpace(Heap* heap,
- MarkingDeque* marking_deque) {
- NewSpace* space = heap->new_space();
+void MarkCompactCollector::DiscoverGreyObjectsInNewSpace() {
+ NewSpace* space = heap()->new_space();
NewSpacePageIterator it(space->bottom(), space->top());
while (it.has_next()) {
NewSpacePage* page = it.next();
- DiscoverGreyObjectsOnPage(marking_deque, page);
- if (marking_deque->IsFull()) return;
+ DiscoverGreyObjectsOnPage(page);
+ if (marking_deque()->IsFull()) return;
}
}
isolate()->CountUsage(v8::Isolate::UseCounterFeature::kMarkDequeOverflow);
DCHECK(marking_deque_.overflowed());
- DiscoverGreyObjectsInNewSpace(heap(), &marking_deque_);
+ DiscoverGreyObjectsInNewSpace();
if (marking_deque_.IsFull()) return;
- DiscoverGreyObjectsInSpace(heap(), &marking_deque_, heap()->old_space());
+ DiscoverGreyObjectsInSpace(heap()->old_space());
if (marking_deque_.IsFull()) return;
- DiscoverGreyObjectsInSpace(heap(), &marking_deque_, heap()->code_space());
+ DiscoverGreyObjectsInSpace(heap()->code_space());
if (marking_deque_.IsFull()) return;
- DiscoverGreyObjectsInSpace(heap(), &marking_deque_, heap()->map_space());
+ DiscoverGreyObjectsInSpace(heap()->map_space());
if (marking_deque_.IsFull()) return;
LargeObjectIterator lo_it(heap()->lo_space());
- DiscoverGreyObjectsWithIterator(heap(), &marking_deque_, &lo_it);
+ DiscoverGreyObjectsWithIterator(&lo_it);
if (marking_deque_.IsFull()) return;
marking_deque_.ClearOverflowed();
void SetOverflowed() { overflowed_ = true; }
- // Push the (marked) object on the marking stack if there is room,
- // otherwise mark the object as overflowed and wait for a rescan of the
- // heap.
- INLINE(void PushBlack(HeapObject* object)) {
+ // Push the (marked) object on the marking stack if there is room, otherwise
+ // mark the deque as overflowed and wait for a rescan of the heap.
+ INLINE(bool PushBlack(HeapObject* object)) {
DCHECK(object->IsHeapObject());
if (IsFull()) {
- Marking::BlackToGrey(object);
- MemoryChunk::IncrementLiveBytesFromGC(object, -object->Size());
SetOverflowed();
+ return false;
} else {
array_[top_] = object;
top_ = ((top_ + 1) & mask_);
+ return true;
}
}
}
}
- INLINE(void UnshiftBlack(HeapObject* object)) {
+ INLINE(bool UnshiftBlack(HeapObject* object)) {
DCHECK(object->IsHeapObject());
DCHECK(Marking::IsBlack(Marking::MarkBitFrom(object)));
if (IsFull()) {
- Marking::BlackToGrey(object);
- MemoryChunk::IncrementLiveBytesFromGC(object, -object->Size());
SetOverflowed();
+ return false;
} else {
bottom_ = ((bottom_ - 1) & mask_);
array_[bottom_] = object;
+ return true;
}
}
//
// After: Live objects are marked and non-live objects are unmarked.
- friend class RootMarkingVisitor;
- friend class MarkingVisitor;
- friend class MarkCompactMarkingVisitor;
friend class CodeMarkingVisitor;
+ friend class MarkCompactMarkingVisitor;
+ friend class MarkingVisitor;
+ friend class RootMarkingVisitor;
friend class SharedFunctionInfoMarkingVisitor;
+ friend class IncrementalMarkingMarkingVisitor;
// Mark code objects that are active on the stack to prevent them
// from being flushed.
void AfterMarking();
+ // Pushes a black object onto the marking stack and accounts for live bytes.
+ // Note that this assumes live bytes have not yet been counted.
+ INLINE(void PushBlack(HeapObject* obj));
+
+ // Unshifts a black object into the marking stack and accounts for live bytes.
+ // Note that this assumes lives bytes have already been counted.
+ INLINE(void UnshiftBlack(HeapObject* obj));
+
// Marks the object black and pushes it on the marking stack.
// This is for non-incremental marking only.
INLINE(void MarkObject(HeapObject* obj, MarkBit mark_bit));
// flag on the marking stack.
void RefillMarkingDeque();
+ // Helper methods for refilling the marking stack by discovering grey objects
+ // on various pages of the heap. Used by {RefillMarkingDeque} only.
+ template <class T>
+ void DiscoverGreyObjectsWithIterator(T* it);
+ void DiscoverGreyObjectsOnPage(MemoryChunk* p);
+ void DiscoverGreyObjectsInSpace(PagedSpace* space);
+ void DiscoverGreyObjectsInNewSpace();
+
// Callback function for telling whether the object *p is an unmarked
// heap object.
static bool IsUnmarkedHeapObject(Object** p);