Dynamic skipping and blocking, dead path elimination for cyclic workflows, and a local semantics for inclusive gateways

We propose and study dynamic versions of the classical flexibility constructs 'skip' and 'block' for workflows and motivate and define a formal semantics for them. We show that our semantics is a generalization of dead-path-elimination and solves the open problem to define dead-path-elimination for cyclic workflows. This in turn gives rise to a simple and fully local semantics for inclusive gateways. Finally, we show how our new constructs can be enacted on existing process engines by a workflow transformation that stores control-flow information in process variables.