Symbolic state space reduction with guarded terms for rewriting modulo SMT.

•Guarded terms provide an approach to deal with the symbolic state-explosion problem for rewriting modulo SMT.•A guarded term has the potential to encode many symbolic states into one by using constraints as part of its structure.•Succinct exploration of the symbolic state space can be achieved by reducing branching, and the complexity and size of constraints.•A case study of an unbounded and symbolic priority queue illustrates the approach.