Pretty easy to work out. Hulk may have basically limitless strength, but no matter what incarnation of superman we look at, he's got more speed and maneuverability than Hulk could ever hope to reach. If Supes could hold him long enough, he could either toss him into the sun or, toss him in any direction into space. Hulk don't do so well in space, so he would be at the mercy of whatever body of gravity he came too close too in his floating voyage.