| // 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 "src/heap/remembered-set.h" |
| #include "src/heap/heap-inl.h" |
| #include "src/heap/heap.h" |
| #include "src/heap/mark-compact.h" |
| #include "src/heap/slot-set.h" |
| #include "src/heap/spaces.h" |
| #include "src/heap/store-buffer.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| template <PointerDirection direction> |
| void RememberedSet<direction>::ClearInvalidSlots(Heap* heap) { |
| STATIC_ASSERT(direction == OLD_TO_NEW); |
| for (MemoryChunk* chunk : *heap->old_space()) { |
| SlotSet* slots = GetSlotSet(chunk); |
| if (slots != nullptr) { |
| slots->Iterate([heap, chunk](Address addr) { |
| Object** slot = reinterpret_cast<Object**>(addr); |
| return IsValidSlot(heap, chunk, slot) ? KEEP_SLOT : REMOVE_SLOT; |
| }); |
| } |
| } |
| } |
| |
| template <PointerDirection direction> |
| void RememberedSet<direction>::VerifyValidSlots(Heap* heap) { |
| Iterate(heap, [heap](Address addr) { |
| HeapObject* obj = |
| heap->mark_compact_collector()->FindBlackObjectBySlotSlow(addr); |
| if (obj == nullptr) { |
| // The slot is in dead object. |
| MemoryChunk* chunk = MemoryChunk::FromAnyPointerAddress(heap, addr); |
| AllocationSpace owner = chunk->owner()->identity(); |
| // The old to old remembered set should not have dead slots. |
| CHECK_NE(direction, OLD_TO_OLD); |
| // The old to new remembered set is allowed to have slots in dead |
| // objects only in map and large object space because these space |
| // cannot have raw untagged pointers. |
| CHECK(owner == MAP_SPACE || owner == LO_SPACE); |
| } else { |
| int offset = static_cast<int>(addr - obj->address()); |
| CHECK(obj->IsValidSlot(offset)); |
| } |
| return KEEP_SLOT; |
| }); |
| } |
| |
| template <PointerDirection direction> |
| bool RememberedSet<direction>::IsValidSlot(Heap* heap, MemoryChunk* chunk, |
| Object** slot) { |
| STATIC_ASSERT(direction == OLD_TO_NEW); |
| Object* object = *slot; |
| if (!heap->InNewSpace(object)) { |
| return false; |
| } |
| HeapObject* heap_object = HeapObject::cast(object); |
| // If the target object is not black, the source slot must be part |
| // of a non-black (dead) object. |
| return Marking::IsBlack(Marking::MarkBitFrom(heap_object)) && |
| heap->mark_compact_collector()->IsSlotInBlackObject( |
| chunk, reinterpret_cast<Address>(slot)); |
| } |
| |
| template void RememberedSet<OLD_TO_NEW>::ClearInvalidSlots(Heap* heap); |
| template void RememberedSet<OLD_TO_NEW>::VerifyValidSlots(Heap* heap); |
| template void RememberedSet<OLD_TO_OLD>::VerifyValidSlots(Heap* heap); |
| |
| } // namespace internal |
| } // namespace v8 |