A parallel prefix circuit takes n inputs x1, x2, . . . , xn and produces the n outputs x1, x1 ◦ x2, . . . , x1 ◦ x2 ◦ · · · ◦ xn, where ‘◦’ is an arbitrary associative binary operation. Parallel prefix circuits and their counterparts in software, parallel prefix computations or scans, have numerous applications ranging from fast integer addition over parallel sorting to convex hull problems. A ...