   0  inline_call_r_r <JitCode 'build_node_tree'>, R[%r0] -> %r0
   6  -live- %r0
   6  residual_call_r_v $<* fn validate_node>, R[%r0], <CallDescr(r) EF=5>
  12  -live- %r0
  12  new_with_vtable <rpython.jit.backend.llsupport.descr.SizeDescr object at 0x16fafb30> -> %r1
  16  setfield_gc_r %r1, %r0, FieldDescr<pypy.module.parser.pyparser.W_STType.inst_tree>
  21  setfield_gc_r %r1, $<* struct rpy_string>, FieldDescr<pypy.module.parser.pyparser.W_STType.inst_mode>
  26  ref_return %r1
