Abstract
We give parallel NC algorithms for recognizing reducible flow graphs (rfg’s), and for finding dominators, minimum feedback vertex sets, and a depth first search numbering in an rfg. We show that finding a minimum feedback vertex set in vertex-weighted rfg’s or finding a minimum feedback arc set in arc-weighted rfg’s is P-complete. We present RNC algorithms for finding a minimum feedback arc set in an unweighted rfg, and for finding a minimum weight feedback set when arc or vertex weights are in unary; and we show that these problems are in NC if and only if the maximum matching problem is in NC.
Funded by National Foundation Grant ECS 8404866, the Semiconductor Research Corporation Grant 86-12-109 and the Joint Services Electronics Program Grant N00014-84-C-0149.
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Ramachandran, V. (1988). Fast Parallel Algorithms for Reducible Flow Graphs. In: Tewksbury, S.K., Dickinson, B.W., Schwartz, S.C. (eds) Concurrent Computations. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-5511-3_8
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