.RESTORE_PSECT retrieves the program section from the top of
    the program section context stack, an internal stack in the
    assembler. If the stack is empty when .RESTORE_PSECT is issued,
    the assembler displays an error message. When .RESTORE_PSECT
    retrieves a program section, it restores the current location
    counter to the value it had when the program section was saved.
    The maximum stack level is 50. See the description of .SAVE_PSECT
    for more information.