A method for correcting the functionality of a wire-pipelined circuit

ABSTRACT

As across-chip interconnect delays can exceed a clock cycle, wire pipelining becomes essential in high performance designs. Although it allows higher clock frequencies, it may change the microarchitecture altogether because of the arbitrary increase in the latencies of the paths and cycles of the circuit. This paper proposes a method to regain the functionality of a wire-pipelined circuit. In this approach, increased cycle latencies are compensated by slowing down the issue rate of the inputs. Our method finds the optimal value of the slowdown required for a circuit as it directly affects the throughput of the circuit. We also incorporate area minimization in our formulation to minimize the number of extra flip-flops added to the circuit. The formulation is tested on circuits derived from ISCAS benchmarks and the results suggest that wire pipelining increases the overall throughput in most of the cases.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids

General Terms:
Algorithms, Performance

Keywords:
synchronous design, wire pipelining