Heterogeneous technology mapping for FPGAs with dual-port embedded memory arrays

ABSTRACT

It has become clear that on-chip storage is an essential component of high-density FPGAs. These arrays were originally intended to implement storage, but recent work has shown that they can also be used to implement logic very efficiently. This previous work has only considered single-port arrays. Many current FPGAs, however, contain dual-port arrays. In this paper we present an algorithm that maps logic to these dual-port arrays. Our algorithm can either optimize area with no regard for circuit speed, or optimize area under the constraint that the combinational depth of the circuit does not increase. Experimental results show that, on average, our algorithm packs between 29% and 35% more logic than an algorithm that targets single-port arrays. We also show, however, that even with this algorithm, dual-port arrays are still not as area-efficient as single-port arrays when implementing logic.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS

Additional Classification:
  B. Hardware
  B.6 LOGIC DESIGN

General Terms:
Design, Experimentation, Performance