  A quantum annealer exploits quantum effects to solve a particular type of
optimization problem. The advantage of this specialized hardware is that it
effectively considers all possible solutions in parallel, thereby potentially
outperforming classical computing systems. However, despite quantum annealers
having recently become commercially available, there are relatively few
high-level programming models that target these devices.
  In this article, we show how to compile a subset of Prolog enhanced with
support for constraint logic programming into a 2-local Ising-model Hamiltonian
suitable for execution on a quantum annealer. In particular, we describe the
series of transformations one can apply to convert constraint logic programs
expressed in Prolog into an executable form that bears virtually no resemblance
to a classical machine model yet that evaluates the specified constraints in a
fully parallel manner. We evaluate our efforts on a 1095-qubit D-Wave 2X
quantum annealer and describe the approach's associated capabilities and
shortcomings.
  Under consideration in Theory and Practice of Logic Programming (TPLP).
