We can iterate a scan on scavange page if it was precisely swept or just added to the old generatio…

src/store-buffer.cc

 // Copyright 2011 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.
 
 #include "src/store-buffer.h"
 
 #include <algorithm>
 
 #include "src/v8.h"
 
@@ skipping 506 matching lines @@
           LargePage* large_page = reinterpret_cast<LargePage*>(chunk);
           HeapObject* array = large_page->GetObject();
           ASSERT(array->IsFixedArray());
           Address start = array->address();
           Address end = start + array->Size();
           FindPointersToNewSpaceInRegion(start, end, slot_callback, clear_maps);
         } else {
           Page* page = reinterpret_cast<Page*>(chunk);
           ASSERT(page->owner() == heap_->map_space() ||
                  page->owner() == heap_->old_pointer_space());
-          CHECK(page->WasSweptPrecisely());
+          CHECK(!page->WasSweptConservatively());
 
           HeapObjectIterator iterator(page, NULL);
           for (HeapObject* heap_object = iterator.Next();
                heap_object != NULL;
                heap_object = iterator.Next()) {
             // We iterate over objects that contain pointers only.
             if (heap_object->ContainsPointers()) {
               FindPointersToNewSpaceInRegion(
                   heap_object->address() + HeapObject::kHeaderSize,
                   heap_object->address() + heap_object->Size(),
@@ skipping 58 matching lines @@
     }
     old_buffer_is_sorted_ = false;
     old_buffer_is_filtered_ = false;
     *old_top_++ = reinterpret_cast<Address>(int_addr << kPointerSizeLog2);
     ASSERT(old_top_ <= old_limit_);
   }
   heap_->isolate()->counters()->store_buffer_compactions()->Increment();
 }
 
 } }  // namespace v8::internal