const ClusteringPolicySet &policies, ValuesConstraintSet &constraints,
    bool resolve, bool emit_remarks) {
  // A set of constraints for operation results.
  llvm::DenseMap<Operation *, ValuesConstraintSet> op_results_constraints;
  assert(filter && "filter predicate must be defined");

  // Use initial constraints to initialize op results constraints.
  for (std::pair<Value, ValueConstraint> pair : constraints) {