- BugFix: a - a is NOT 0 for NaN's - a * 0 is NOT 0 for Inf
- BugFix: a - a is NOT 0 for NaN's
- a * 0 is NOT 0 for Inf

[r23192]

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