Precise deadlock detection for polychronous data-flow specifications

Dependency graphs are a commonly used data structure to encode the streams of values in data-flow programs and play a central role in scheduling instructions during automated code generation from such specifications. In this work, we propose a precise and effective method that combines a structure of dependency graph and first order logic formulas to check whether multi-clocked data-flow specifications are deadlock free before generating code from them. We represent the flow of values in the source programs by means of a dependency graph and attach first-order logic formulas to condition these dependencies. We use an SMT solver to effectively reason about the implied formulas and check deadlock freedom.