text: from __future__ import print_function
  
  from future.utils import viewitems
  
  from miasm.arch.x86.arch import mn_x86
  from miasm.expression.expression import get_rw
  from miasm.arch.x86.ira import ir_a_x86_32
  from miasm.core.locationdb import LocationDB
  
  loc_db = LocationDB()
  
  
  print("""
  Simple expression manipulation demo.
  Get read/written registers for a given instruction
  """)
  
  arch = mn_x86
  ir_arch = ir_a_x86_32(loc_db)
  ircfg = ir_arch.new_ircfg()
  instr = arch.fromstring('LODSB', loc_db, 32)
  instr.offset, instr.l = 0, 15
  ir_arch.add_instr_to_ircfg(instr, ircfg)
  
  print('*' * 80)
  for lbl, irblock in viewitems(ircfg.blocks):
      print(irblock)
      for assignblk in irblock:
          rw = assignblk.get_rw()
          for dst, reads in viewitems(rw):
              print('read:   ', [str(x) for x in reads])
              print('written:', dst)
              print()
  
  open('graph_instr.dot', 'w').write(ircfg.dot())
  