Mechanized logical relations for termination-insensitive noninterference

We present an expressive information-flow control type system with recursive types, existential label polymorphism, and impredicative polymorphism for a higher-order programming language state. give novel semantic model of this show that well-typed programs satisfy termination-insensitive noninterference. Our approach supports compositional integration syntactically ill-typed---but semantically sound---components, which we demonstrate through several interesting examples. define our using logical relations on top the Iris program logic framework; to capture termination-insensitivity, develop language-agnostic theory Modal Weakest Preconditions. formalize all examples in Coq proof assistant.