Abstract
Local search methods such as WSAT have proven to be successful for solving SAT problems. In this paper, we propose two host-FPGA (Field Programmable Gate Array) co-implementations, which use modified WSAT algorithms to solve SAT problems. Our implementations are reconfigurable in real-time for different problem instances. On an XCV1000 FPGA chip, SAT problems up to 100 variables and 220 clauses can be solved. The first implementation is based on a random strategy and achieves one flip per clock cycle through the use of pipelining. The second uses a greedy heuristic at the expense of FPGA space consumption, which precludes pipelining. Both of the two implementations avoid re-synthesis, placement, routing for different SAT problems, and show improved performance over previously published reconfigurable SAT implementations on FPGAs.
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Yap, R.H.C., Wang, S.Z.Q., Henz, M.J. (2003). Hardware Implementations of Real-Time Reconfigurable WSAT Variants. In: Y. K. Cheung, P., Constantinides, G.A. (eds) Field Programmable Logic and Application. FPL 2003. Lecture Notes in Computer Science, vol 2778. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-45234-8_48
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DOI: https://doi.org/10.1007/978-3-540-45234-8_48
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