{
    Copyright (c) 1998-2002 by Florian Klaempfl and Carl Eric Codere

    Generate PowerPC assembler for in set/case nodes

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 ****************************************************************************
}
unit nppcset;

{$I fpcdefs.inc}

interface

uses
  node, nset, ncgset, cpubase, cgbase, cgobj, aasmbase, aasmtai;

type

  tppccasenode = class(tcgcasenode)
  protected
    procedure genlinearlist(hp: pcaselabel); override;
  end;

implementation

uses
  globtype, systems,
  verbose, globals,
  symconst, symdef, defutil,
  paramgr,
  cpuinfo,
  pass_2, cgcpu,
  ncon,
  tgobj, ncgutil, regvars, rgobj, aasmcpu;

{*****************************************************************************
                            TCGCASENODE
*****************************************************************************}

procedure tppccasenode.genlinearlist(hp: pcaselabel);

var
  first, lastrange: boolean;
  last: TConstExprInt;

  procedure genitem(t: pcaselabel);

    procedure gensub(value: aint);
    var
      tmpreg: tregister;
    begin
      value := -value;
      if (value >= low(smallint)) and
        (value <= high(smallint)) then
        exprasmlist.concat(taicpu.op_reg_reg_const(A_ADDIC_, hregister,
          hregister, value))
      else
      begin
        tmpreg := cg.getintregister(exprasmlist, OS_INT);
        cg.a_load_const_reg(exprasmlist, OS_INT, value, tmpreg);
        exprasmlist.concat(taicpu.op_reg_reg_reg(A_ADD_, hregister,
          hregister, tmpreg));
      end;
    end;

  begin
    if assigned(t^.less) then
      genitem(t^.less);
    { need we to test the first value }
    if first and (t^._low > get_min_value(left.resulttype.def)) then
    begin
      cg.a_cmp_const_reg_label(exprasmlist, OS_INT, jmp_lt, aword(t^._low),
        hregister, elselabel);
    end;
    if t^._low = t^._high then
    begin
      if t^._low - last = 0 then
        cg.a_cmp_const_reg_label(exprasmlist, opsize, OC_EQ, 0, hregister,
          blocklabel(t^.blockid))
      else
        gensub(aint(t^._low - last));
      tcgppc(cg).a_jmp_cond(exprasmlist, OC_EQ, blocklabel(t^.blockid));
      last := t^._low;
      lastrange := false;
    end
    else
    begin
      { it begins with the smallest label, if the value }
      { is even smaller then jump immediately to the    }
      { ELSE-label                                }
      if first then
      begin
        { have we to ajust the first value ? }
        if (t^._low > get_min_value(left.resulttype.def)) then
          gensub(aint(t^._low));
      end
      else
      begin
        { if there is no unused label between the last and the }
        { present label then the lower limit can be checked    }
        { immediately. else check the range in between:       }
        gensub(aint(t^._low - last));
        if ((t^._low - last) <> 1) or
          (not lastrange) then
          tcgppc(cg).a_jmp_cond(exprasmlist, jmp_lt, elselabel);
      end;
      gensub(aint(t^._high - t^._low));
      tcgppc(cg).a_jmp_cond(exprasmlist, jmp_le, blocklabel(t^.blockid));
      last := t^._high;
      lastrange := true;
    end;
    first := false;
    if assigned(t^.greater) then
      genitem(t^.greater);
  end;

begin
  { do we need to generate cmps? }
  if (with_sign and (min_label < 0)) or
    (opsize = OS_32) then
    genlinearcmplist(hp)
  else
  begin
    last := 0;
    lastrange := false;
    first := true;
    genitem(hp);
    cg.a_jmp_always(exprasmlist, elselabel);
  end;
end;

begin
  ccasenode := tppccasenode;
end.