Replace slots buffer with remembered set.

src/heap/mark-compact-inl.h

Index: src/heap/mark-compact-inl.h
diff --git a/src/heap/mark-compact-inl.h b/src/heap/mark-compact-inl.h
index f117acee9b12f8a28d0af898eb0bcb04176cf715..9cc7d7c39e57ceb75f5bb78eb3293f26a2c160cb 100644
--- a/src/heap/mark-compact-inl.h
+++ b/src/heap/mark-compact-inl.h
@@ -6,7 +6,7 @@
 #define V8_HEAP_MARK_COMPACT_INL_H_
 
 #include "src/heap/mark-compact.h"
-#include "src/heap/slots-buffer.h"
+#include "src/heap/remembered-set.h"
 #include "src/isolate.h"
 
 namespace v8 {
@@ -70,25 +70,11 @@ bool MarkCompactCollector::IsMarked(Object* obj) {
 void MarkCompactCollector::RecordSlot(HeapObject* object, Object** slot,
                                       Object* target) {
   Page* target_page = Page::FromAddress(reinterpret_cast<Address>(target));
+  Page* source_page = Page::FromAddress(reinterpret_cast<Address>(object));
   if (target_page->IsEvacuationCandidate() &&
       !ShouldSkipEvacuationSlotRecording(object)) {
-    if (!SlotsBuffer::AddTo(slots_buffer_allocator_,
-                            target_page->slots_buffer_address(), slot,
-                            SlotsBuffer::FAIL_ON_OVERFLOW)) {
-      EvictPopularEvacuationCandidate(target_page);
-    }
-  }
-}
-
-
-void MarkCompactCollector::ForceRecordSlot(HeapObject* object, Object** slot,
-                                           Object* target) {
-  Page* target_page = Page::FromAddress(reinterpret_cast<Address>(target));
-  if (target_page->IsEvacuationCandidate() &&
-      !ShouldSkipEvacuationSlotRecording(object)) {
-    CHECK(SlotsBuffer::AddTo(slots_buffer_allocator_,
-                             target_page->slots_buffer_address(), slot,
-                             SlotsBuffer::IGNORE_OVERFLOW));
+    RememberedSet<OLD_TO_OLD>::Insert(source_page,

[jochen (gone - plz use gerrit), 2016/02/23 13:10:53]

so we now just crash if we can't grow the remembered set?

[ulan, 2016/02/23 13:19:07]

Yes, as discussed offline, the remembered set filters out duplicates so its size
is limited.

+                                      reinterpret_cast<Address>(slot));
   }
 }