Decompose Mul(x, 2**b + 2**a) into y = x + x << (b - a), y << a instead of y = x << a, y + y << (b - a). This is beneficial for address mode generation.
Decompose Mul(x, 2**b + 2**a) into y = x + x << (b - a), y << a instead of y = x << a, y + y << (b - a). This is beneficial for address mode generation.

[r16240]

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