Change RecordSlot interface. Make it more robust by replacing anchor slot with actual object.

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index e403feb5c717ba2e4328abceeb88b8a0fd28f46f..a5b322cf3975bcf7f7847f798e0faddbf21cb8a3 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -640,11 +640,6 @@ class MarkCompactCollector {
   void VerifyOmittedMapChecks();
 #endif
 
-  INLINE(static bool ShouldSkipEvacuationSlotRecording(Object** anchor)) {

[Michael Starzinger, 2015/08/04 15:20:12]

Woot! I love it!

-    return Page::FromAddress(reinterpret_cast<Address>(anchor))
-        ->ShouldSkipEvacuationSlotRecording();
-  }
-
   INLINE(static bool ShouldSkipEvacuationSlotRecording(Object* host)) {
     return Page::FromAddress(reinterpret_cast<Address>(host))
         ->ShouldSkipEvacuationSlotRecording();
@@ -656,11 +651,11 @@ class MarkCompactCollector {
   }
 
   void RecordRelocSlot(RelocInfo* rinfo, Object* target);
-  void RecordCodeEntrySlot(Address slot, Code* target);
+  void RecordCodeEntrySlot(HeapObject* object, Address slot, Code* target);
   void RecordCodeTargetPatch(Address pc, Code* target);
 
   INLINE(void RecordSlot(
-      Object** anchor_slot, Object** slot, Object* object,
+      HeapObject* source, Object** slot, Object* target,

[Michael Starzinger, 2015/08/04 15:20:12]

nit: s/source/object/ for consistency.

[Hannes Payer (out of office), 2015/08/04 16:16:21]

Done.

       SlotsBuffer::AdditionMode mode = SlotsBuffer::FAIL_ON_OVERFLOW));
 
   void MigrateObject(HeapObject* dst, HeapObject* src, int size,