Prepare cake according to package directions and bake in a 9x13 inch pan. Let cool completely. Cut half the cake into 1-inch cubes (saving the other half for another dessert).
In a large bowl, beat together pudding mix and milk until thick and creamy. Beat in cream cheese until fluffy. Fold in half the whipped topping.
In a large punch or trifle bowl, layer one-third of the cake cubes, one-third of the cream cheese mixture, one-third of the banana slices and one-third of the pecans. Top with one-third of the fudge sauce.
Repeat cake and cream cheese layers and top with half the cherry pie filling. Cover the pie filling with one-third of the bananas, one-third of the pecans and one-third of the fudge sauce.
Repeat step 4, omitting the pecan layer. Top with remaining whipped topping; drizzle with remaining fudge sauce; and sprinkle with remaining pecans. Refrigerate 4 hours before serving.