prolog/epilog

[sevtov]

       Hi, all!

      I've observed RTL-code for i386, ARM and AVR machine and
      I found that i386 and ARM RTL contain the code for
      epilog&prolog of a function 

      (note 79 58 80 NOTE_INSN_EPILOGUE_BEG)
      ...
      ...


      ...
      ...
      (note 78 77 5 NOTE_INSN_PROLOGUE_END)


      But AVR-RTL-code doesn't. Why???

      Thank you.