Post-Placement Functional Decomposition for FPGAs
Abstract
This work explores the effect of adding a simple functional
decomposition step to the traditional field programmable
gate array (FPGA) CAD flow. Once placement has completed,
alternative decompositions of the logic on the critical
path are examined for potential delay improvements. The
placed circuit is then modified to use the best decompositions
found. Any placement illegalities introduced by the
new decompositions are resolved by an incremental placement
step. Experiments conducted on Alteras Stratix chips
indicate that this functional decomposition technique can
provide a performance improvement of 7.6% on average, and
up to 26.3% on a set of industrial designs.
Reference
Valavan Manohararajah, Deshanand P. Singh, and Stephen D. Brown, "Post-Placement Functional Decomposition for FPGAs", in Proceedings of the International Workshop on Logic and Synthesis, Temecula, CA, June 2004, pp. 114-118.
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