Fixing m68hc11 reorg after dataflow merge

[Rask Ingemann Lambertsen]

   I need some help making m68hc11_reorg() work after the dataflow merge, in
particular this bit:

  /* Re-create the REG_DEAD notes.  These notes are used in the machine
     description to use the best assembly directives.  */
  if (optimize)
    {
      /* Before recomputing the REG_DEAD notes, remove all of them.
         This is necessary because the reload_cse_regs() pass can
         have replaced some (MEM) with a register.  In that case,
         the REG_DEAD that could exist for that register may become
         wrong.  */
      for (insn = first; insn; insn = NEXT_INSN (insn))
        {
          if (INSN_P (insn))
            {
              rtx *pnote;

              pnote = &REG_NOTES (insn);
              while (*pnote != 0)
                {
                  if (REG_NOTE_KIND (*pnote) == REG_DEAD)
                    *pnote = XEXP (*pnote, 1);
                  else
                    pnote = &XEXP (*pnote, 1);
                }
            }
        }

      life_analysis (PROP_REG_INFO | PROP_DEATH_NOTES);
    }

-- 
Rask Ingemann Lambertsen