[heap] Only visit strong links during scavenge of promoted objects

src/heap/mark-compact.h

 // Copyright 2012 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.
 
 #ifndef V8_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include <deque>
 
 #include "src/base/bits.h"
@@ skipping 455 matching lines @@
   void VerifyWeakEmbeddedObjectsInCode();
   void VerifyOmittedMapChecks();
 #endif
 
   INLINE(static bool ShouldSkipEvacuationSlotRecording(Object* host)) {
     return Page::FromAddress(reinterpret_cast<Address>(host))
         ->ShouldSkipEvacuationSlotRecording();
   }
 
   INLINE(static bool IsOnEvacuationCandidate(Object* obj)) {
-    return Page::FromAddress(reinterpret_cast<Address>(obj))
-        ->IsEvacuationCandidate();
+    return obj->IsHeapObject() &&
+           Page::FromAddress(reinterpret_cast<Address>(obj))
+               ->IsEvacuationCandidate();
   }
 
   void RecordRelocSlot(Code* host, RelocInfo* rinfo, Object* target);
   void RecordCodeEntrySlot(HeapObject* host, Address slot, Code* target);
   void RecordCodeTargetPatch(Address pc, Code* target);
   INLINE(void RecordSlot(HeapObject* object, Object** slot, Object* target));
   INLINE(void ForceRecordSlot(HeapObject* object, Object** slot,
                               Object* target));
 
   void UpdateSlots(SlotsBuffer* buffer);
@@ skipping 284 matching lines @@
 
  private:
   MarkCompactCollector* collector_;
 };
 
 V8_EXPORT_PRIVATE const char* AllocationSpaceName(AllocationSpace space);
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_MARK_COMPACT_H_