Lower bounds on the iteration time and the initiation interval of functional pipelining and loop folding

The performance of pipelined datapath implementations is measured basically by three parameters: the clock cycle length, the initiation interval between successive iterations (inverse of the throughput) and the iteration time (turn-around time). In this paper we present a new method for computing performance bounds of pipelined implementations: • Given an iterative behavior, a set of resource constraints and a target initiation interval, we derive a lower bound on the iteration time achievable by any pipelined implementation. • Given an iterative behavior and a set of resource constraints, we derive a lower bound on the initiation interval achievable by any pipelined implementation. The method has a low complexity and it handles behavioral specifications containing loop statements with inter-iteration data dependency and timing constrains.