Fixed calculation of optimizations.

src/optimize/__init__.py

@@ -63,6 +63,6 @@ def optimize(statements, verbose=0):
         print 'After global optimization:       %d' % g
         print 'After basic blocks optimization: %d' % b
         print 'Optimization:                    %d (%d%%)' \
-                % (b - o, int((b - o) / float(o) * 100))
+                % (o - b, int((o - b) / float(b) * 100))
 
     return opt_blocks