example of conversion

from.c

    case MVM_OP_unshift_i: return &MVM_repr_unshift_i;
    case MVM_OP_unshift_n: return &MVM_repr_unshift_n;


    case MVM_OP_unshift_n:
    case MVM_OP_push_n: {
        MVMint32 invocant = ins->operands[0].reg.orig;
        MVMint32 value    = ins->operands[1].reg.orig;
        MVMJitCallArg args[] = { { MVM_JIT_INTERP_VAR, MVM_JIT_INTERP_TC },
                                 { MVM_JIT_REG_VAL, invocant },
                                 { MVM_JIT_REG_VAL_F, value } };
        jg_append_call_c(tc, jgb->graph, op_to_func(tc, op), 3, args, MVM_JIT_RV_VOID, -1);
        break;
    }

to.lisp

(template: unshift_n
   (call (^func &MVM_repr_unshift_n)
          (arglist 3 
              (carg (tc) ptr)
              (carg $0 ptr)
              (carg $1 num))
          void))