Generalized Matrix Factorization Techniques for Approximate Logic Synthesis
Soheil Hashemia and Sherief Redab
School of Engineering, Brown University, Providence
asoheil_hashemi@brown.edu
bsherief_reda@brown.edu
ABSTRACT
Approximate computing is an emerging computing paradigm, where computing accuracy is relaxed for improvements in hardware metrics, such as design area and power profile. In circuit design, a major challenge is to synthesize approximate circuits automatically from input exact circuits. In this work, we extend our previous work, BLASYS, for approximate logic synthesis based on matrix factorization, where an arbitrary input circuit can be approximated in a controlled fashion. Whereas our previous approach uses a semi-ring algebra for factorization, this work generalizes matrix-based circuit factorization to include both semi-ring and field algebra implementations. We also propose a new method for truth table folding to improve the factorization quality. These new approaches significantly widen the design space of possible approximate circuits, effectively offering improved trade-offs in terms of quality, area and power consumption. We evaluate our methodology on a number of representative circuits showcasing the benefits of our proposed methodology for approximate logic synthesis.
