TY - GEN

T1 - Synthesis of uninitialized systems

AU - Henzinger, Thomas A.

AU - Krishnan, Sriram C.

AU - Kupferman, Orna

AU - Mang, Freddy Y.C.

PY - 2002

Y1 - 2002

N2 - The sequential synthesis problem, which is closely related to Church's solvability problem, asks, given a specification in the form of a binary relation between input and output streams, for the construction of a finite-state stream transducer that converts inputs to appropriate outputs. For efficiency reasons, practical sequential hardware is often designed to operate without prior initialization. Such hardware designs can be modeled by uninitialized state machines, which are required to satisfy their specification if started from any state. In this paper we solve the sequential synthesis problem for uninitialized systems, that is, we construct uninitialized finite-state stream transducers. We consider specifications given by LTL formulas, deterministic, nondeterministic, universal, and alternating Büchi automata. We solve this uninitialized synthesis problem by reducing it to the well-understood initialized synthesis problem. While our solution is straightforward, it leads, for some specification formalisms, to upper bounds that are exponentially worse than the complexity of the corresponding initialized problems. However, we prove lower bounds to show that our simple solutions are optimal for all considered specification formalisms. We also study the problem of deciding whether a given specification is uninitialized, that is, if its uninitialized and initialized synthesis problems coincide. We show that this problem has, for each specification formalism, the same complexity as the equivalence problem.

AB - The sequential synthesis problem, which is closely related to Church's solvability problem, asks, given a specification in the form of a binary relation between input and output streams, for the construction of a finite-state stream transducer that converts inputs to appropriate outputs. For efficiency reasons, practical sequential hardware is often designed to operate without prior initialization. Such hardware designs can be modeled by uninitialized state machines, which are required to satisfy their specification if started from any state. In this paper we solve the sequential synthesis problem for uninitialized systems, that is, we construct uninitialized finite-state stream transducers. We consider specifications given by LTL formulas, deterministic, nondeterministic, universal, and alternating Büchi automata. We solve this uninitialized synthesis problem by reducing it to the well-understood initialized synthesis problem. While our solution is straightforward, it leads, for some specification formalisms, to upper bounds that are exponentially worse than the complexity of the corresponding initialized problems. However, we prove lower bounds to show that our simple solutions are optimal for all considered specification formalisms. We also study the problem of deciding whether a given specification is uninitialized, that is, if its uninitialized and initialized synthesis problems coincide. We show that this problem has, for each specification formalism, the same complexity as the equivalence problem.

UR - http://www.scopus.com/inward/record.url?scp=84869149457&partnerID=8YFLogxK

U2 - 10.1007/3-540-45465-9_55

DO - 10.1007/3-540-45465-9_55

M3 - Conference contribution

AN - SCOPUS:84869149457

SN - 3540438645

SN - 9783540438649

T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

SP - 644

EP - 656

BT - Automata, Languages and Programming - 29th International Colloquium, ICALP 2002, Proceedings

A2 - Widmayer, Peter

A2 - Eidenbenz, Stephan

A2 - Triguero, Francisco

A2 - Morales, Rafael

A2 - Conejo, Ricardo

A2 - Hennessy, Matthew

PB - Springer Verlag

T2 - 29th International Colloquium on Automata, Languages, and Programming, ICALP 2002

Y2 - 8 July 2002 through 13 July 2002

ER -