Version 4.5.103.24 (cherry-pick)

src/heap/mark-compact.cc

Index: src/heap/mark-compact.cc
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index 8bbfeb173f7ba3ac5e55b63145e62d3085338727..9ca06cf2e64c449188656fd494ae84370ccde554 100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -3058,11 +3058,18 @@ bool MarkCompactCollector::TryPromoteObject(HeapObject* object,
 
 bool MarkCompactCollector::IsSlotInBlackObject(Page* p, Address slot,
                                                HeapObject** out_object) {
-  // This function does not support large objects right now.
   Space* owner = p->owner();
   if (owner == heap_->lo_space() || owner == NULL) {
-    *out_object = NULL;
-    return true;
+    Object* large_object = heap_->lo_space()->FindObject(slot);
+    // This object has to exist, otherwise we would not have recorded a slot
+    // for it.
+    CHECK(large_object->IsHeapObject());
+    HeapObject* large_heap_object = HeapObject::cast(large_object);
+    if (IsMarked(large_heap_object)) {
+      *out_object = large_heap_object;
+      return true;
+    }
+    return false;
   }
 
   uint32_t mark_bit_index = p->AddressToMarkbitIndex(slot);
@@ -3179,13 +3186,8 @@ bool MarkCompactCollector::IsSlotInLiveObject(Address slot) {
     return false;
   }
 
-  // |object| is NULL only when the slot belongs to large object space.
-  DCHECK(object != NULL ||
-         Page::FromAnyPointerAddress(heap_, slot)->owner() ==
-             heap_->lo_space());
-  // We don't need to check large objects' layout descriptor since it can't
-  // contain in-object fields anyway.
-  if (object != NULL) {
+  DCHECK(object != NULL);
+
     switch (object->ContentType()) {
       case HeapObjectContents::kTaggedValues:
         return true;
@@ -3214,9 +3216,7 @@ bool MarkCompactCollector::IsSlotInLiveObject(Address slot) {
       }
     }
     UNREACHABLE();
-  }
-
-  return true;
+    return true;
 }
 
 
@@ -4444,12 +4444,10 @@ void SlotsBuffer::RemoveInvalidSlots(Heap* heap, SlotsBuffer* buffer) {
       ObjectSlot slot = slots[slot_idx];
       if (!IsTypedSlot(slot)) {
         Object* object = *slot;
-        if (object->IsHeapObject()) {
-          if (heap->InNewSpace(object) ||
-              !heap->mark_compact_collector()->IsSlotInLiveObject(
-                  reinterpret_cast<Address>(slot))) {
-            slots[slot_idx] = kRemovedEntry;
-          }
+        if ((object->IsHeapObject() && heap->InNewSpace(object)) ||
+            !heap->mark_compact_collector()->IsSlotInLiveObject(
+                reinterpret_cast<Address>(slot))) {
+          slots[slot_idx] = kRemovedEntry;
         }
       } else {
         ++slot_idx;
@@ -4506,9 +4504,10 @@ void SlotsBuffer::VerifySlots(Heap* heap, SlotsBuffer* buffer) {
       if (!IsTypedSlot(slot)) {
         Object* object = *slot;
         if (object->IsHeapObject()) {
+          HeapObject* heap_object = HeapObject::cast(object);
           CHECK(!heap->InNewSpace(object));
-          CHECK(heap->mark_compact_collector()->IsSlotInLiveObject(
-              reinterpret_cast<Address>(slot)));
+          heap->mark_compact_collector()->VerifyIsSlotInLiveObject(
+              reinterpret_cast<Address>(slot), heap_object);
         }
       } else {
         ++slot_idx;