MOVES Seminar 6 July 2010, 10:30
Carsten Fuhs
Synthesizing Shortest Linear Straight-Line Programs over GF(2) using SAT
Abstract:
Non-trivial linear straight-line programs over the Galois field of
two elements occur frequently in applications such as encryption or
high-performance computing. Finding the shortest linear straight-line
program for a given set of linear forms is known to be MaxSNP-complete,
i.e., there is no epsilon-approximation for the problem unless P = NP.
We present a non-approximative approach for finding the shortest linear
straight-line program. In other words, we show how to search for a
circuit of XOR gates with the minimal number of such gates. The
approach is based on a reduction of the associated decision problem
("Is there a program of length k?") to satisfiability of propositional
logic. Using modern SAT solvers, optimal solutions to interesting
problem instances can be obtained.
two elements occur frequently in applications such as encryption or
high-performance computing. Finding the shortest linear straight-line
program for a given set of linear forms is known to be MaxSNP-complete,
i.e., there is no epsilon-approximation for the problem unless P = NP.
We present a non-approximative approach for finding the shortest linear
straight-line program. In other words, we show how to search for a
circuit of XOR gates with the minimal number of such gates. The
approach is based on a reduction of the associated decision problem
("Is there a program of length k?") to satisfiability of propositional
logic. Using modern SAT solvers, optimal solutions to interesting
problem instances can be obtained.

