   0  -live- %r1
   0  goto_if_not_ptr_nonzero %r1, L1
   4  ref_copy %r1 -> %r0
   7  -live- %r0, %r1
   7  guard_class %r1 -> %i0
  10  -live- %i0, %r0
  10  goto_if_not_int_eq %i0, $<* struct object_vtable>, L2
  15  residual_call_ir_r $<* fn W_Dtype.descr_get_descr>, I[$False], R[%r0, $<* struct rpy_string>], <CallDescr(rri) EF=7> -> %r0
  25  -live- %r0
  25  ref_return %r0
  27  ---
  27  L2:
  27  raise $<* struct object>
  29  ---
  29  L1:
  29  raise $<* struct object>
