   0  getfield_gc_r %r0, FieldDescr<pypy.objspace.std.setobject.W_BaseSetObject.inst_strategy> -> %r2
   5  -live- %r0, %r1, %r2
   5  guard_class %r2 -> %i0
   8  getfield_raw_i %i0, FieldDescr<pypy.objspace.std.setobject.SetStrategy_vtable.cls_copy_real> -> %i0
  13  -live- %i0, %r0, %r1, %r2
  13  int_guard_value %i0
  15  residual_call_r_r %i0, <IndirectCallTargets>, R[%r2, %r0], <CallDescr(rr) EF=7> -> %r0
  23  -live- %r0, %r1
  23  residual_call_r_r $<* fn W_BaseSetObject.descr_difference_update>, R[%r0, %r1], <CallDescr(rr) EF=7> -> %r1
  31  -live- %r0
  31  ref_return %r0
