added code to detect loops in unreachable code, these would cause endless loops else :-(
added code to detect loops in unreachable code, these would cause
endless loops else :-(

[r6684]

libfirm/libfirm,davidgiven/libfirm,MatzeB/libfirm,killbug2004/libfirm,jonashaag/libfirm,killbug2004/libfirm,davidgiven/libfirm,MatzeB/libfirm,libfirm/libfirm,8l/libfirm,jonashaag/libfirm,killbug2004/libfirm,8l/libfirm,8l/libfirm,8l/libfirm,jonashaag/libfirm,jonashaag/libfirm,davidgiven/libfirm,8l/libfirm,davidgiven/libfirm,davidgiven/libfirm,libfirm/libfirm,davidgiven/libfirm,jonashaag/libfirm,killbug2004/libfirm,MatzeB/libfirm,MatzeB/libfirm,MatzeB/libfirm,killbug2004/libfirm,8l/libfirm,jonashaag/libfirm,davidgiven/libfirm,MatzeB/libfirm,8l/libfirm,MatzeB/libfirm,killbug2004/libfirm,jonashaag/libfirm,killbug2004/libfirm,libfirm/libfirm,libfirm/libfirm