freepascal.compiler/compiler/i8086/aoptcpu.pas

{
    Copyright (c) 1998-2004 by Jonas Maebe

    This unit calls the optimization procedures to optimize the assembler
    code for sparc

    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 aoptcpu;

{$i fpcdefs.inc}

  Interface

    uses
      cpubase, aoptobj, aoptcpub, aopt,
      aasmtai;

    Type
      TCpuAsmOptimizer = class(TAsmOptimizer)
        function PeepHoleOptPass1Cpu(var p : tai) : boolean; override;
      End;

  Implementation

    uses
      verbose,
      aoptx86,
      aasmcpu;

    function TCpuAsmOptimizer.PeepHoleOptPass1Cpu(var p : tai) : boolean;
      var
        hp1 : tai;
        hp2 : tai;
      begin
        result:=false;
        case p.typ of
          ait_instruction:
            begin
              case taicpu(p).opcode of
                A_MOV:
                  begin
                    if MatchInstruction(p,A_MOV,[S_W]) and
                      MatchOpType(p,top_ref,top_reg) and

                      GetNextInstruction(p, hp1) and
                      MatchInstruction(hp1,A_MOV,[S_W]) and
                      MatchOpType(hp1,top_ref,top_reg) and

                      GetNextInstruction(hp1, hp2) and
                      MatchInstruction(hp2,A_MOV,[S_W]) and
                      MatchOpType(hp2,top_reg,top_reg) and

                      not(OpsEqual(taicpu(p).oper[1]^,taicpu(hp1).oper[1]^)) and

                      OpsEqual(taicpu(hp1).oper[1]^,taicpu(hp2).oper[0]^) and

                      (MatchOperand(taicpu(hp2).oper[1]^,NR_ES) or MatchOperand(taicpu(hp2).oper[1]^,NR_DS)) and

                      (taicpu(p).oper[0]^.ref^.base=taicpu(hp1).oper[0]^.ref^.base) and
                      (taicpu(p).oper[0]^.ref^.index=taicpu(hp1).oper[0]^.ref^.index) and
                      (taicpu(p).oper[0]^.ref^.segment=taicpu(hp1).oper[0]^.ref^.segment) and
                      (taicpu(p).oper[0]^.ref^.symbol=taicpu(hp1).oper[0]^.ref^.symbol) and
                      (taicpu(p).oper[0]^.ref^.relsymbol=taicpu(hp1).oper[0]^.ref^.relsymbol) and
                      (taicpu(p).oper[0]^.ref^.offset+2=taicpu(hp1).oper[0]^.ref^.offset) and
                      assigned(FindRegDealloc(taicpu(hp2).oper[0]^.reg,tai(hp2.Next)))  then
                      begin
                        case taicpu(hp2).oper[1]^.reg of
                          NR_DS:
                            taicpu(p).opcode:=A_LDS;
                          NR_ES:
                            taicpu(p).opcode:=A_LES;
                          else
                            internalerror(2015092601);
                        end;
                        asml.remove(hp1);
                        hp1.free;
                        asml.remove(hp2);
                        hp2.free;
                        result:=true;
                      end;
                  end;
              end
            end
        end;
      end;

begin
  casmoptimizer:=TCpuAsmOptimizer;
end.