Holas,
Puedes imprimirlo del tipo heredoc o nowdoc:
Código PHP:
Ver original<?php
echo <<<EOD
<script type="text/javascript">
(function() {var _impid = 155084;var _pieceid = 5383;var _js = (("https:" == document.location.protocol) ? "https://" : "http://") + "soicos.com/srv.php?impid="+_impid+"&pieceid="+_pieceid+"&s=.js";document.write(unescape("%3Cscript src='" + _js + "' type='text/javascript'%3E%3C/script%3E"));})();
</script>
EOD;
Saludos