def merge_ptr_read(known, ptrs):
    """
    Merge common memory parts in a multiple byte memory.
    @ptrs: memory bytes list
    @known: ptrs' associated boolean for present/unpresent memory part in the
    store
    """
    assert known
    out = []
    known.append(None)
    ptrs.append(None)
    last, value, size = known[0], ptrs[0], 8
    for index, part in enumerate(known[1:], 1):
        if part == last:
            size += 8
        else:
            out.append((last, value, size))
            last, value, size = part, ptrs[index], 8
    return out
