[heap] Black allocation.

src/heap/remembered-set.cc

Index: src/heap/remembered-set.cc
diff --git a/src/heap/remembered-set.cc b/src/heap/remembered-set.cc
index f41318c312fbb1be2ba2ad369c4ed77b252280e1..d1d8a33bc377c3ce26dbec2476837e60a6d6e31b 100644
--- a/src/heap/remembered-set.cc
+++ b/src/heap/remembered-set.cc
@@ -33,21 +33,23 @@ void RememberedSet<direction>::ClearInvalidSlots(Heap* heap) {
 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 spaces cannot
-      // have raw untaged pointers.
-      CHECK(owner == MAP_SPACE || owner == LO_SPACE);
-    } else {
-      int offset = static_cast<int>(addr - obj->address());
-      CHECK(obj->IsValidSlot(offset));
+    if (!Page::FromAddress(addr)->IsFlagSet(Page::BLACK_PAGE)) {
+      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;
   });