Fix WeakMap processing for evacuation candidates.

src/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 319 matching lines @@
   VerifyMarkbitsAreClean(heap_->old_data_space());
   VerifyMarkbitsAreClean(heap_->code_space());
   VerifyMarkbitsAreClean(heap_->cell_space());
   VerifyMarkbitsAreClean(heap_->map_space());
   VerifyMarkbitsAreClean(heap_->new_space());
 
   LargeObjectIterator it(heap_->lo_space());
   for (HeapObject* obj = it.Next(); obj != NULL; obj = it.Next()) {
     MarkBit mark_bit = Marking::MarkBitFrom(obj);
     ASSERT(Marking::IsWhite(mark_bit));
+    ASSERT_EQ(0, Page::FromAddress(obj->address())->LiveBytes());
   }
 }
 #endif
 
 
 static void ClearMarkbitsInPagedSpace(PagedSpace* space) {
   PageIterator it(space);
 
   while (it.has_next()) {
     Bitmap::Clear(it.next());
@@ skipping 16 matching lines @@
   ClearMarkbitsInPagedSpace(heap_->old_pointer_space());
   ClearMarkbitsInPagedSpace(heap_->old_data_space());
   ClearMarkbitsInPagedSpace(heap_->cell_space());
   ClearMarkbitsInNewSpace(heap_->new_space());
 
   LargeObjectIterator it(heap_->lo_space());
   for (HeapObject* obj = it.Next(); obj != NULL; obj = it.Next()) {
     MarkBit mark_bit = Marking::MarkBitFrom(obj);
     mark_bit.Clear();
     mark_bit.Next().Clear();
+    Page::FromAddress(obj->address())->ResetLiveBytes();
   }
 }
 
 
 bool Marking::TransferMark(Address old_start, Address new_start) {
   // This is only used when resizing an object.
   ASSERT(MemoryChunk::FromAddress(old_start) ==
          MemoryChunk::FromAddress(new_start));
 
   // If the mark doesn't move, we don't check the color of the object.
@@ skipping 2199 matching lines @@
 
 
 void MarkCompactCollector::ProcessWeakMaps() {
   Object* weak_map_obj = encountered_weak_maps();
   while (weak_map_obj != Smi::FromInt(0)) {
     ASSERT(MarkCompactCollector::IsMarked(HeapObject::cast(weak_map_obj)));
     JSWeakMap* weak_map = reinterpret_cast<JSWeakMap*>(weak_map_obj);
     ObjectHashTable* table = ObjectHashTable::cast(weak_map->table());
     for (int i = 0; i < table->Capacity(); i++) {
       if (MarkCompactCollector::IsMarked(HeapObject::cast(table->KeyAt(i)))) {
-        Object* value = table->get(table->EntryToValueIndex(i));
-        StaticMarkingVisitor::VisitPointer(heap(), &value);
-        table->set_unchecked(heap(),
-                             table->EntryToValueIndex(i),
-                             value,
-                             UPDATE_WRITE_BARRIER);
+        int idx = ObjectHashTable::EntryToValueIndex(i);
+        Object** slot =
+            HeapObject::RawField(table, FixedArray::OffsetOfElementAt(idx));
+        StaticMarkingVisitor::VisitPointer(heap(), slot);
       }
     }
     weak_map_obj = weak_map->next();
   }
 }
 
 
 void MarkCompactCollector::ClearWeakMaps() {
   Object* weak_map_obj = encountered_weak_maps();
   while (weak_map_obj != Smi::FromInt(0)) {
@@ skipping 1524 matching lines @@
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 
 
 } }  // namespace v8::internal