TSO Games -- On the decidability of safety games under the total store order semantics (extended LMCS version with appendix)

TL;DR

This paper extends the classical Total Store Order (TSO) semantics to turn-based safety games, analyzing the decidability of various message transfer scenarios between processes and shared memory.

Contribution

It provides a complete decidability classification for different formulations of safety games under extended TSO semantics.

Findings

Decidability results for all message transfer scenarios

Extension of TSO semantics to turn-based safety games

Complete classification of problem decidability

Abstract

We consider an extension of the classical Total Store Order (TSO) semantics by expanding it to turn-based 2-player safety games. During her turn, a player can select any of the communicating processes and perform its next transition. We consider different formulations of the safety game problem depending on whether one player or both of them transfer messages from the process buffers to the shared memory. We give the complete decidability picture for all the possible alternatives.