Document smt_bit_vector_theoryt::negate

Author: thomasspriggs

src/solvers/smt2_incremental/smt_bit_vector_theory.h

@@ -245,6 +245,7 @@ class smt_bit_vector_theoryt
     static smt_sortt return_sort(const smt_termt &operand);
     static void validate(const smt_termt &operand);
   };
+  /// \brief Arithmetic negation in two's complement.
   static const smt_function_application_termt::factoryt<negatet> negate;
 
   // Shift operations