Paste: pseudocode

bool trace_partial_object(cell start, cell end, cell card_start, cell card_end)
{
	if(card_start >= end) return false;
	if(end >= card_end) end = card_end;

	cell *slot_ptr = (cell *)start;
	cell *end_ptr = (cell *)end;

	bool copied = false;

	if(slot_ptr != end_ptr)
	{
		slot++;
		for(; slot_ptr < end_ptr; slot++) copied |= trace_handle(slot_ptr);
	}

	return copied;
}

template<typename SourceGeneration, typename Unmarker>
void trace_cards(SourceGeneration *gen, card mask, Unmarker unmarker)
{
	u64 start = current_micros();

	card_deck *decks = this->data->decks;
	card_deck *cards = this->data->cards;

	cell first_deck = card_deck_index(gen->start);
	cell last_deck = card_deck_index(gen->end);

	cell start = 0, binary_start = 0, end = 0;

	for(cell deck_index = first_deck; deck_index < last_deck; deck_index++)
	{
		if(decks[deck_index] & mask)
		{
			cell first_card = card_index(deck_index);
			cell last_card = card_index(deck_index + 1);

			bool deck_dirty = false;

			for(cell card_index = first_card; card_index < last_card; card_index++)
			{
				if(cards[card_index] & mask)
				{
					if(card_start >= end)
					{
						start = find_card_containing_header(card_index);
						binary_start = start + myvm->binary_payload_start((object *)start);
						end = start + myvm->untagged_object_size((object *)start);
					}

					bool card_dirty = false;

					while(start < card_end_offset(card_index))
					{
						card_dirty |= trace_partial_object(
							start,
							binary_start,
							card_start_offset(card_index),
							card_end_offset(card_index));
						start = gen->next_object_after(start);
						binary_start = start + myvm->binary_payload_start((object *)start);
						end = start + myvm->untagged_object_size((object *)start);
					}

					unmarker(copied,&cards[card_index]);
					this->myvm->gc_stats.cards_scanned++;

					deck_dirty |= card_dirty;
				}
			}

			unmarker(copied,&decks[deck_index]);
		}
	}

	this->myvm->gc_stats.card_scan_time += (current_micros() - start);
}