freepascal.compiler/compiler/i386/n386flw.pas

{
    $Id$
    Copyright (c) 1998-2000 by Florian Klaempfl

    Generate i386 assembler for nodes that influence the flow

    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 n386flw;

{$i defines.inc}

interface

    uses
      node,nflw;

    type
       ti386whilerepeatnode = class(twhilerepeatnode)
          procedure pass_2;override;
       end;

       ti386ifnode = class(tifnode)
          procedure pass_2;override;
       end;

       ti386fornode = class(tfornode)
          procedure pass_2;override;
       end;

       ti386exitnode = class(texitnode)
          procedure pass_2;override;
       end;

       ti386breaknode = class(tbreaknode)
          procedure pass_2;override;
       end;

       ti386continuenode = class(tcontinuenode)
          procedure pass_2;override;
       end;

       ti386gotonode = class(tgotonode)
          procedure pass_2;override;
       end;

       ti386labelnode = class(tlabelnode)
          procedure pass_2;override;
       end;

       ti386raisenode = class(traisenode)
          procedure pass_2;override;
       end;

       ti386tryexceptnode = class(ttryexceptnode)
          procedure pass_2;override;
       end;

       ti386tryfinallynode = class(ttryfinallynode)
          procedure pass_2;override;
       end;

       ti386onnode = class(tonnode)
          procedure pass_2;override;
       end;

       ti386failnode = class(tfailnode)
          procedure pass_2;override;
       end;

implementation

    uses
      verbose,globtype,globals,systems,
      symconst,symdef,symsym,aasm,types,
      hcodegen,temp_gen,pass_2,
      cpubase,cpuasm,
      pass_1,nld,ncon,
      cgai386,tgcpu,n386util,regvars;

{*****************************************************************************
                         Second_While_RepeatN
*****************************************************************************}

    procedure ti386whilerepeatnode.pass_2;
      var
         lcont,lbreak,lloop,
         oldclabel,oldblabel : tasmlabel;
         otlabel,oflabel : tasmlabel;

         //start_regvars_loaded,
         //then_regvars_loaded: regvar_booleanarray;

      begin
         getlabel(lloop);
         getlabel(lcont);
         getlabel(lbreak);
         { arrange continue and breaklabels: }
         oldclabel:=aktcontinuelabel;
         oldblabel:=aktbreaklabel;

         load_all_regvars(exprasmlist);
         { handling code at the end as it is much more efficient, and makes
           while equal to repeat loop, only the end true/false is swapped (PFV) }
         if nodetype=whilen then
           emitjmp(C_None,lcont);

         { align loop target }
         exprasmList.concat(Tai_align.Create(aktalignment.loopalign));
         emitlab(lloop);

         aktcontinuelabel:=lcont;
         aktbreaklabel:=lbreak;
         cleartempgen;
         if assigned(right) then
           secondpass(right);

         load_all_regvars(exprasmlist);

         emitlab(lcont);
         otlabel:=truelabel;
         oflabel:=falselabel;
         if nodetype=whilen then
          begin
            truelabel:=lloop;
            falselabel:=lbreak;
          end
         { repeatn }
         else
          begin
            truelabel:=lbreak;
            falselabel:=lloop;
          end;
         cleartempgen;
         secondpass(left);

         load_all_regvars(exprasmlist);

         maketojumpbool(left);
         emitlab(lbreak);
         truelabel:=otlabel;
         falselabel:=oflabel;


         aktcontinuelabel:=oldclabel;
         aktbreaklabel:=oldblabel;
         { a break/continue in a while/repeat block can't be seen outside }
         flowcontrol:=flowcontrol-[fc_break,fc_continue];
      end;


{*****************************************************************************
                               TI386IFNODE
*****************************************************************************}

    procedure ti386ifnode.pass_2;

      var
         hl,otlabel,oflabel : tasmlabel;

      begin
         otlabel:=truelabel;
         oflabel:=falselabel;
         getlabel(truelabel);
         getlabel(falselabel);
         cleartempgen;
         secondpass(left);
         load_all_regvars(exprasmlist);
         maketojumpbool(left);
         if assigned(right) then
           begin
              emitlab(truelabel);
              cleartempgen;
              secondpass(right);
              { automatically done for blocks, but not for statements (JM) }
              load_all_regvars(exprasmlist);
           end;
         if assigned(t1) then
           begin
              if assigned(right) then
                begin
                   getlabel(hl);
                   { do go back to if line !! }
                   aktfilepos:=exprasmList.getlasttaifilepos^;
                   emitjmp(C_None,hl);
                end;
              emitlab(falselabel);
              cleartempgen;
              secondpass(t1);
              load_all_regvars(exprasmlist);
              if assigned(right) then
                emitlab(hl);
           end
         else
           begin
              emitlab(falselabel);
           end;
         if not(assigned(right)) then
           begin
              emitlab(truelabel);
           end;
         truelabel:=otlabel;
         falselabel:=oflabel;
      end;


{*****************************************************************************
                              SecondFor
*****************************************************************************}

    procedure ti386fornode.pass_2;
      var
         l3,oldclabel,oldblabel : tasmlabel;
         omitfirstcomp,temptovalue : boolean;
         hs : byte;
         temp1 : treference;
         hop : tasmop;
         hcond : tasmcond;
         cmpreg,cmp32 : tregister;
         opsize : topsize;
         count_var_is_signed : boolean;

      begin
         oldclabel:=aktcontinuelabel;
         oldblabel:=aktbreaklabel;
         getlabel(aktcontinuelabel);
         getlabel(aktbreaklabel);
         getlabel(l3);

         { could we spare the first comparison ? }
         omitfirstcomp:=false;
         if right.nodetype=ordconstn then
           if tassignmentnode(left).right.nodetype=ordconstn then
             omitfirstcomp:=((nf_backward in flags) and
               (tordconstnode(tassignmentnode(left).right).value>=tordconstnode(right).value))
               or (not(nf_backward in flags) and
                  (tordconstnode(tassignmentnode(left).right).value<=tordconstnode(right).value));

         { only calculate reference }
         cleartempgen;
         secondpass(t2);
         hs:=t2.resulttype.def.size;
         if t2.location.loc <> LOC_CREGISTER then
           cmp32:=getregister32;
         case hs of
            1 : begin
                   opsize:=S_B;
                   if t2.location.loc <> LOC_CREGISTER then
                     cmpreg:=reg32toreg8(cmp32);
                end;
            2 : begin
                   opsize:=S_W;
                   if t2.location.loc <> LOC_CREGISTER then
                     cmpreg:=reg32toreg16(cmp32);
                end;
            4 : begin
                   opsize:=S_L;
                   if t2.location.loc <> LOC_CREGISTER then
                     cmpreg:=cmp32;
                end;
         end;

         { first set the to value
           because the count var can be in the expression !! }
         cleartempgen;
         secondpass(right);
         { calculate pointer value and check if changeable and if so }
         { load into temporary variable                       }
         if right.nodetype<>ordconstn then
           begin
              temp1.symbol:=nil;
              gettempofsizereference(hs,temp1);
              temptovalue:=true;
              if (right.location.loc=LOC_REGISTER) or
                 (right.location.loc=LOC_CREGISTER) then
                begin
                   emit_reg_ref(A_MOV,opsize,right.location.register,
                      newreference(temp1));
                 end
              else
                 concatcopy(right.location.reference,temp1,hs,false,false);
           end
         else
           temptovalue:=false;

         { produce start assignment }
         cleartempgen;
         secondpass(left);
         count_var_is_signed:=is_signed(torddef(t2.resulttype.def));
         if temptovalue then
             begin
              if t2.location.loc=LOC_CREGISTER then
                begin
                   emit_ref_reg(A_CMP,opsize,newreference(temp1),
                     t2.location.register);
                end
              else
                begin
                   emit_ref_reg(A_MOV,opsize,newreference(t2.location.reference),
                     cmpreg);
                   emit_ref_reg(A_CMP,opsize,newreference(temp1),
                     cmpreg);
                   { temp register not necessary anymore currently (JM) }
                   ungetregister32(cmp32);
                end;
           end
         else
             begin
              if not(omitfirstcomp) then
                begin
                   if t2.location.loc=LOC_CREGISTER then
                     emit_const_reg(A_CMP,opsize,tordconstnode(right).value,
                       t2.location.register)
                   else
                     emit_const_ref(A_CMP,opsize,tordconstnode(right).value,
                       newreference(t2.location.reference));
                end;
           end;
         if nf_backward in flags then
           if count_var_is_signed then
             hcond:=C_L
           else
             hcond:=C_B
         else
           if count_var_is_signed then
             hcond:=C_G
           else
             hcond:=C_A;

         load_all_regvars(exprasmlist);

         if not(omitfirstcomp) or temptovalue then
           emitjmp(hcond,aktbreaklabel);

         { align loop target }
         exprasmList.concat(Tai_align.Create(aktalignment.loopalign));
         emitlab(l3);

         { help register must not be in instruction block }
         cleartempgen;
         if assigned(t1) then
           begin
             secondpass(t1);
             load_all_regvars(exprasmlist);
           end;

         emitlab(aktcontinuelabel);

         { makes no problems there }
         cleartempgen;

         if (t2.location.loc <> LOC_CREGISTER) then
           begin
             { demand help register again }
             cmp32:=getregister32;
             case hs of
                1 : cmpreg:=reg32toreg8(cmp32);
                2 : cmpreg:=reg32toreg16(cmp32);
                4 : cmpreg:=cmp32;
             end;
           end;

         { produce comparison and the corresponding }
         { jump                              }
         if temptovalue then
           begin
              if t2.location.loc=LOC_CREGISTER then
                begin
                   emit_ref_reg(A_CMP,opsize,newreference(temp1),
                     t2.location.register);
                end
              else
                begin
                   emit_ref_reg(A_MOV,opsize,newreference(t2.location.reference),
                     cmpreg);
                   emit_ref_reg(A_CMP,opsize,newreference(temp1),
                     cmpreg);
                    end;
           end
         else
           begin
              if t2.location.loc=LOC_CREGISTER then
                emit_const_reg(A_CMP,opsize,tordconstnode(right).value,
                  t2.location.register)
              else
                 emit_const_ref(A_CMP,opsize,tordconstnode(right).value,
                   newreference(t2.location.reference));
           end;
         if nf_backward in flags then
           if count_var_is_signed then
             hcond:=C_LE
           else
             hcond:=C_BE
          else
            if count_var_is_signed then
              hcond:=C_GE
            else
              hcond:=C_AE;
         load_all_regvars(exprasmlist);
         emitjmp(hcond,aktbreaklabel);
         { according to count direction DEC or INC... }
         { must be after the test because of 0 to 255 for bytes !! }
         if nf_backward in flags then
           hop:=A_DEC
         else
           hop:=A_INC;

         if t2.location.loc=LOC_CREGISTER then
           emit_reg(hop,opsize,t2.location.register)
         else
           emit_ref(hop,opsize,newreference(t2.location.reference));
         emitjmp(C_None,l3);

         if (t2.location.loc <> LOC_CREGISTER) then
           ungetregister32(cmp32);
         if temptovalue then
           ungetiftemp(temp1);

         { this is the break label: }
         emitlab(aktbreaklabel);

         aktcontinuelabel:=oldclabel;
         aktbreaklabel:=oldblabel;
         { a break/continue in a for block can't be seen outside }
         flowcontrol:=flowcontrol-[fc_break,fc_continue];
      end;


{*****************************************************************************
                              SecondExitN
*****************************************************************************}

    procedure ti386exitnode.pass_2;

      var
         {op : tasmop;
         s : topsize;}
         otlabel,oflabel : tasmlabel;
         r : preference;
         is_mem,
         allocated_eax,
         allocated_edx: boolean;

      procedure cleanleft;
        begin
          if is_mem then
            begin
              del_reference(left.location.reference);
              ungetiftemp(left.location.reference);
            end
          else
            begin
              ungetregister(left.location.register);
              if left.location.registerhigh <> R_NO then
                ungetregister(left.location.registerhigh);
            end;
        end;

      label
         do_jmp;
      begin
         load_all_regvars(exprasmlist);
         include(flowcontrol,fc_exit);
         if assigned(left) then
         if left.nodetype=assignn then
           begin
              { just do a normal assignment followed by exit }
              secondpass(left);
              emitjmp(C_None,aktexitlabel);
           end
         else
           begin
              allocated_eax := false;
              allocated_edx := false;
              otlabel:=truelabel;
              oflabel:=falselabel;
              getlabel(truelabel);
              getlabel(falselabel);
              secondpass(left);
              case left.location.loc of
                 LOC_FPU : goto do_jmp;
                 LOC_MEM,
           LOC_REFERENCE : is_mem:=true;
           LOC_CREGISTER,
            LOC_REGISTER : is_mem:=false;
               LOC_FLAGS : begin
                             exprasmlist.concat(tairegalloc.alloc(R_EAX));
                             allocated_eax := true;
                             emit_flag2reg(left.location.resflags,R_AL);
                             goto do_jmp;
                           end;
                LOC_JUMP : begin
                             exprasmlist.concat(tairegalloc.alloc(R_EAX));
                             allocated_eax := true;
                             emitlab(truelabel);
                             emit_const_reg(A_MOV,S_B,1,R_AL);
                             emitjmp(C_None,aktexit2label);
                             emitlab(falselabel);
                             emit_reg_reg(A_XOR,S_B,R_AL,R_AL);
                             goto do_jmp;
                           end;
              else
                internalerror(2001);
              end;
              case procinfo^.returntype.def.deftype of
           pointerdef,
           procvardef : begin
                          cleanleft;
                          exprasmlist.concat(tairegalloc.alloc(R_EAX));
                          allocated_eax := true;
                          if is_mem then
                            emit_ref_reg(A_MOV,S_L,
                              newreference(left.location.reference),R_EAX)
                          else
                            emit_reg_reg(A_MOV,S_L,
                              left.location.register,R_EAX);
                        end;
             floatdef : begin
                          cleanleft;
                          if is_mem then
                           floatload(tfloatdef(procinfo^.returntype.def).typ,left.location.reference);
                        end;
              { orddef,
              enumdef : }
              else
              { it can be anything shorter than 4 bytes PM
              this caused form bug 711 }
                       begin
                          cleanleft;
                          exprasmlist.concat(tairegalloc.alloc(R_EAX));
                          allocated_eax := true;
                          case procinfo^.returntype.def.size of
                           { it can be a qword/int64 too ... }
                           8 : if is_mem then
                                 begin
                                    emit_ref_reg(A_MOV,S_L,
                                      newreference(left.location.reference),R_EAX);
                                    r:=newreference(left.location.reference);
                                    inc(r^.offset,4);
                                    exprasmlist.concat(tairegalloc.alloc(R_EDX));
                                    allocated_edx := true;
                                    emit_ref_reg(A_MOV,S_L,r,R_EDX);
                                 end
                               else
                                 begin
                                    emit_reg_reg(A_MOV,S_L,left.location.registerlow,R_EAX);
                                    exprasmlist.concat(tairegalloc.alloc(R_EDX));
                                    allocated_edx := true;
                                    emit_reg_reg(A_MOV,S_L,left.location.registerhigh,R_EDX);
                                 end;
                          { if its 3 bytes only we can still
                            copy one of garbage ! PM }
                           4,3 : if is_mem then
                                 emit_ref_reg(A_MOV,S_L,
                                   newreference(left.location.reference),R_EAX)
                               else
                                 emit_reg_reg(A_MOV,S_L,left.location.register,R_EAX);
                           2 : if is_mem then
                                 emit_ref_reg(A_MOV,S_W,
                                   newreference(left.location.reference),R_AX)
                               else
                                 emit_reg_reg(A_MOV,S_W,makereg16(left.location.register),R_AX);
                           1 : if is_mem then
                                 emit_ref_reg(A_MOV,S_B,
                                   newreference(left.location.reference),R_AL)
                               else
                                 emit_reg_reg(A_MOV,S_B,makereg8(left.location.register),R_AL);
                           else internalerror(605001);
                          end;
                        end;
              end;
do_jmp:
              truelabel:=otlabel;
              falselabel:=oflabel;
              emitjmp(C_None,aktexit2label);
              if allocated_eax then
                exprasmlist.concat(tairegalloc.dealloc(R_EAX));
              if allocated_edx then
                exprasmlist.concat(tairegalloc.dealloc(R_EDX));
           end
         else
            emitjmp(C_None,aktexitlabel);
       end;


{*****************************************************************************
                              SecondBreakN
*****************************************************************************}

    procedure ti386breaknode.pass_2;
      begin
         include(flowcontrol,fc_break);
         if aktbreaklabel<>nil then
           begin
             load_all_regvars(exprasmlist);
             emitjmp(C_None,aktbreaklabel)
           end
         else
           CGMessage(cg_e_break_not_allowed);
      end;


{*****************************************************************************
                              SecondContinueN
*****************************************************************************}

    procedure ti386continuenode.pass_2;
      begin
         include(flowcontrol,fc_continue);
         if aktcontinuelabel<>nil then
           begin
             load_all_regvars(exprasmlist);
             emitjmp(C_None,aktcontinuelabel)
           end
         else
           CGMessage(cg_e_continue_not_allowed);
      end;


{*****************************************************************************
                             SecondGoto
*****************************************************************************}

    procedure ti386gotonode.pass_2;

       begin
         load_all_regvars(exprasmlist);
         emitjmp(C_None,labelnr);
       end;


{*****************************************************************************
                             SecondLabel
*****************************************************************************}

    procedure ti386labelnode.pass_2;
      begin
         load_all_regvars(exprasmlist);
         emitlab(labelnr);
         cleartempgen;
         secondpass(left);
      end;


{*****************************************************************************
                             SecondRaise
*****************************************************************************}

    procedure ti386raisenode.pass_2;

      var
         a : tasmlabel;
      begin
         if assigned(left) then
           begin
              { multiple parameters? }
              if assigned(right) then
                begin
                  { push frame }
                  if assigned(frametree) then
                    begin
                      secondpass(frametree);
                      if codegenerror then
                       exit;
                      emit_push_loc(frametree.location);
                    end
                  else
                    emit_const(A_PUSH,S_L,0);
                  { push address }
                  secondpass(right);
                  if codegenerror then
                   exit;
                  emit_push_loc(right.location);
                end
              else
                begin
                   getaddrlabel(a);
                   emitlab(a);
                   emit_reg(A_PUSH,S_L,R_EBP);
                   emit_sym(A_PUSH,S_L,a);
                end;
              { push object }
              secondpass(left);
              if codegenerror then
                exit;
              emit_push_loc(left.location);
              emitcall('FPC_RAISEEXCEPTION');
           end
         else
           begin
              emitcall('FPC_POPADDRSTACK');
              emitcall('FPC_RERAISE');
           end;
       end;


{*****************************************************************************
                             SecondTryExcept
*****************************************************************************}

    var
       endexceptlabel : tasmlabel;

    { does the necessary things to clean up the object stack }
    { in the except block                                    }
    procedure cleanupobjectstack;

      begin
         emitcall('FPC_POPOBJECTSTACK');
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_PUSH,S_L,R_EAX);
         emitcall('FPC_DESTROYEXCEPTION');
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         maybe_loadself;
      end;

    { pops one element from the exception address stack }
    { and removes the flag                              }
    procedure cleanupaddrstack;

      begin
         emitcall('FPC_POPADDRSTACK');
         { allocate eax }
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_POP,S_L,R_EAX);
         { deallocate eax }
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
      end;

    procedure ti386tryexceptnode.pass_2;

      var
         exceptlabel,doexceptlabel,oldendexceptlabel,
         lastonlabel,
         exitexceptlabel,
         continueexceptlabel,
         breakexceptlabel,
         exittrylabel,
         continuetrylabel,
         breaktrylabel,
         doobjectdestroy,
         doobjectdestroyandreraise,
         oldaktexitlabel,
         oldaktexit2label,
         oldaktcontinuelabel,
         oldaktbreaklabel : tasmlabel;
         oldflowcontrol,tryflowcontrol,
         exceptflowcontrol : tflowcontrol;
         tempbuf,tempaddr : treference;

      label
         errorexit;
      begin
         oldflowcontrol:=flowcontrol;
         flowcontrol:=[];
         { this can be called recursivly }
         oldendexceptlabel:=endexceptlabel;

         { we modify EAX }
         usedinproc:=usedinproc or ($80 shr byte(R_EAX));

         { save the old labels for control flow statements }
         oldaktexitlabel:=aktexitlabel;
         oldaktexit2label:=aktexit2label;
         if assigned(aktbreaklabel) then
           begin
              oldaktcontinuelabel:=aktcontinuelabel;
              oldaktbreaklabel:=aktbreaklabel;
           end;

         { get new labels for the control flow statements }
         getlabel(exittrylabel);
         getlabel(exitexceptlabel);
         if assigned(aktbreaklabel) then
           begin
              getlabel(breaktrylabel);
              getlabel(continuetrylabel);
              getlabel(breakexceptlabel);
              getlabel(continueexceptlabel);
           end;

         getlabel(exceptlabel);
         getlabel(doexceptlabel);
         getlabel(endexceptlabel);
         getlabel(lastonlabel);

         gettempofsizereferencepersistant(24,tempbuf);
         gettempofsizereferencepersistant(12,tempaddr);
         emitpushreferenceaddr(tempaddr);
         emitpushreferenceaddr(tempbuf);
         push_int (1); { push type of exceptionframe }
         emitcall('FPC_PUSHEXCEPTADDR');

         { allocate eax }
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_PUSH,S_L,R_EAX);
         emitcall('FPC_SETJMP');
         emit_reg(A_PUSH,S_L,R_EAX);
         emit_reg_reg(A_TEST,S_L,R_EAX,R_EAX);
         { deallocate eax }
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         emitjmp(C_NE,exceptlabel);

         { try block }
         { set control flow labels for the try block }
         aktexitlabel:=exittrylabel;
         aktexit2label:=exittrylabel;
         if assigned(oldaktbreaklabel) then
          begin
            aktcontinuelabel:=continuetrylabel;
            aktbreaklabel:=breaktrylabel;
          end;

         flowcontrol:=[];
         secondpass(left);
         tryflowcontrol:=flowcontrol;
         if codegenerror then
           goto errorexit;

         emitlab(exceptlabel);
         emitcall('FPC_POPADDRSTACK');
         ungetpersistanttempreference(tempaddr);
         ungetpersistanttempreference(tempbuf);

         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_POP,S_L,R_EAX);
         emit_reg_reg(A_TEST,S_L,R_EAX,R_EAX);
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));

         emitjmp(C_E,endexceptlabel);
         emitlab(doexceptlabel);

         { set control flow labels for the except block }
         { and the on statements                        }
         aktexitlabel:=exitexceptlabel;
         aktexit2label:=exitexceptlabel;
         if assigned(oldaktbreaklabel) then
          begin
            aktcontinuelabel:=continueexceptlabel;
            aktbreaklabel:=breakexceptlabel;
          end;

         flowcontrol:=[];
         { on statements }
         if assigned(right) then
           secondpass(right);

         emitlab(lastonlabel);
         { default handling except handling }
         if assigned(t1) then
           begin
              { FPC_CATCHES must be called with
                'default handler' flag (=-1)
              }
              push_int (-1);
              emitcall('FPC_CATCHES');
              maybe_loadself;

              { the destruction of the exception object must be also }
              { guarded by an exception frame                        }
              getlabel(doobjectdestroy);
              getlabel(doobjectdestroyandreraise);

              gettempofsizereferencepersistant(12,tempaddr);
              gettempofsizereferencepersistant(24,tempbuf);
              emitpushreferenceaddr(tempaddr);
              emitpushreferenceaddr(tempbuf);
              exprasmList.concat(Taicpu.Op_const(A_PUSH,S_L,1));
              emitcall('FPC_PUSHEXCEPTADDR');

              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              exprasmList.concat(Taicpu.op_reg(A_PUSH,S_L,R_EAX));
              exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
              emitcall('FPC_SETJMP');
              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              exprasmList.concat(Taicpu.op_reg(A_PUSH,S_L,R_EAX));
              exprasmList.concat(Taicpu.op_reg_reg(A_TEST,S_L,R_EAX,R_EAX));
              exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
              emitjmp(C_NE,doobjectdestroyandreraise);

              { here we don't have to reset flowcontrol           }
              { the default and on flowcontrols are handled equal }
              secondpass(t1);
              exceptflowcontrol:=flowcontrol;

              emitlab(doobjectdestroyandreraise);
              emitcall('FPC_POPADDRSTACK');
              ungetpersistanttempreference(tempaddr);
              ungetpersistanttempreference(tempbuf);

              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              exprasmList.concat(Taicpu.op_reg(A_POP,S_L,R_EAX));
              exprasmList.concat(Taicpu.op_reg_reg(A_TEST,S_L,R_EAX,R_EAX));
              exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
              emitjmp(C_E,doobjectdestroy);
              emitcall('FPC_POPSECONDOBJECTSTACK');
              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              emit_reg(A_PUSH,S_L,R_EAX);
              emitcall('FPC_DESTROYEXCEPTION');
              exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
              { we don't need to restore esi here because reraise never }
              { returns                                                 }
              emitcall('FPC_RERAISE');

              emitlab(doobjectdestroy);
              cleanupobjectstack;
              emitjmp(C_None,endexceptlabel);
           end
         else
           begin
              emitcall('FPC_RERAISE');
              exceptflowcontrol:=flowcontrol;
           end;

         if fc_exit in exceptflowcontrol then
           begin
              { do some magic for exit in the try block }
              emitlab(exitexceptlabel);
              { we must also destroy the address frame which guards }
              { exception object                                    }
              cleanupaddrstack;
              cleanupobjectstack;
              emitjmp(C_None,oldaktexitlabel);
           end;

         if fc_break in exceptflowcontrol then
           begin
              emitlab(breakexceptlabel);
              { we must also destroy the address frame which guards }
              { exception object                                    }
              cleanupaddrstack;
              cleanupobjectstack;
              emitjmp(C_None,oldaktbreaklabel);
           end;

         if fc_continue in exceptflowcontrol then
           begin
              emitlab(continueexceptlabel);
              { we must also destroy the address frame which guards }
              { exception object                                    }
              cleanupaddrstack;
              cleanupobjectstack;
              emitjmp(C_None,oldaktcontinuelabel);
           end;

         if fc_exit in tryflowcontrol then
           begin
              { do some magic for exit in the try block }
              emitlab(exittrylabel);
              cleanupaddrstack;
              emitjmp(C_None,oldaktexitlabel);
           end;

         if fc_break in tryflowcontrol then
           begin
              emitlab(breaktrylabel);
              cleanupaddrstack;
              emitjmp(C_None,oldaktbreaklabel);
           end;

         if fc_continue in tryflowcontrol then
           begin
              emitlab(continuetrylabel);
              cleanupaddrstack;
              emitjmp(C_None,oldaktcontinuelabel);
           end;

         emitlab(endexceptlabel);

       errorexit:
         { restore all saved labels }
         endexceptlabel:=oldendexceptlabel;

         { restore the control flow labels }
         aktexitlabel:=oldaktexitlabel;
         aktexit2label:=oldaktexit2label;
         if assigned(oldaktbreaklabel) then
          begin
            aktcontinuelabel:=oldaktcontinuelabel;
            aktbreaklabel:=oldaktbreaklabel;
          end;

         { return all used control flow statements }
         flowcontrol:=oldflowcontrol+exceptflowcontrol+
           tryflowcontrol;
      end;

    procedure ti386onnode.pass_2;
      var
         nextonlabel,
         exitonlabel,
         continueonlabel,
         breakonlabel,
         oldaktexitlabel,
         oldaktexit2label,
         oldaktcontinuelabel,
         doobjectdestroyandreraise,
         doobjectdestroy,
         oldaktbreaklabel : tasmlabel;
         ref : treference;
         oldflowcontrol : tflowcontrol;
         tempbuf,tempaddr : treference;

      begin
         oldflowcontrol:=flowcontrol;
         flowcontrol:=[];
         getlabel(nextonlabel);

         { push the vmt }
         emit_sym(A_PUSH,S_L,
           newasmsymbol(excepttype.vmt_mangledname));
         emitcall('FPC_CATCHES');
         { allocate eax }
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg_reg(A_TEST,S_L,R_EAX,R_EAX);
         emitjmp(C_E,nextonlabel);
         ref.symbol:=nil;
         gettempofsizereference(4,ref);

         { what a hack ! }
         if assigned(exceptsymtable) then
           tvarsym(exceptsymtable.symindex.first).address:=ref.offset;

         emit_reg_ref(A_MOV,S_L,
           R_EAX,newreference(ref));
         { deallocate eax }
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));

         { in the case that another exception is risen }
         { we've to destroy the old one                }
         getlabel(doobjectdestroyandreraise);

         gettempofsizereferencepersistant(12,tempaddr);
         gettempofsizereferencepersistant(24,tempbuf);
         emitpushreferenceaddr(tempaddr);
         emitpushreferenceaddr(tempbuf);
         exprasmList.concat(Taicpu.Op_const(A_PUSH,S_L,1));
         emitcall('FPC_PUSHEXCEPTADDR');

         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         exprasmList.concat(Taicpu.op_reg(A_PUSH,S_L,R_EAX));
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         emitcall('FPC_SETJMP');
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         exprasmList.concat(Taicpu.op_reg(A_PUSH,S_L,R_EAX));
         exprasmList.concat(Taicpu.op_reg_reg(A_TEST,S_L,R_EAX,R_EAX));
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         emitjmp(C_NE,doobjectdestroyandreraise);

         if assigned(right) then
           begin
              oldaktexitlabel:=aktexitlabel;
              oldaktexit2label:=aktexit2label;
              getlabel(exitonlabel);
              aktexitlabel:=exitonlabel;
              aktexit2label:=exitonlabel;
              if assigned(aktbreaklabel) then
               begin
                 oldaktcontinuelabel:=aktcontinuelabel;
                 oldaktbreaklabel:=aktbreaklabel;
                 getlabel(breakonlabel);
                 getlabel(continueonlabel);
                 aktcontinuelabel:=continueonlabel;
                 aktbreaklabel:=breakonlabel;
               end;

              { esi is destroyed by FPC_CATCHES }
              maybe_loadself;
              secondpass(right);
           end;
         getlabel(doobjectdestroy);
         emitlab(doobjectdestroyandreraise);
         emitcall('FPC_POPADDRSTACK');
         ungetpersistanttempreference(tempaddr);
         ungetpersistanttempreference(tempbuf);

         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         exprasmList.concat(Taicpu.op_reg(A_POP,S_L,R_EAX));
         exprasmList.concat(Taicpu.op_reg_reg(A_TEST,S_L,R_EAX,R_EAX));
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         emitjmp(C_E,doobjectdestroy);
         emitcall('FPC_POPSECONDOBJECTSTACK');
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_PUSH,S_L,R_EAX);
         emitcall('FPC_DESTROYEXCEPTION');
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         { we don't need to restore esi here because reraise never }
         { returns                                                 }
         emitcall('FPC_RERAISE');

         emitlab(doobjectdestroy);
         cleanupobjectstack;
         { clear some stuff }
         ungetiftemp(ref);
         emitjmp(C_None,endexceptlabel);

         if assigned(right) then
           begin
              { special handling for control flow instructions }
              if fc_exit in flowcontrol then
                begin
                   { the address and object pop does secondtryexcept }
                   emitlab(exitonlabel);
                   emitjmp(C_None,oldaktexitlabel);
                end;

              if fc_break in flowcontrol then
                begin
                   { the address and object pop does secondtryexcept }
                   emitlab(breakonlabel);
                   emitjmp(C_None,oldaktbreaklabel);
                end;

              if fc_continue in flowcontrol then
                begin
                   { the address and object pop does secondtryexcept }
                   emitlab(continueonlabel);
                   emitjmp(C_None,oldaktcontinuelabel);
                end;

              aktexitlabel:=oldaktexitlabel;
              aktexit2label:=oldaktexit2label;
              if assigned(oldaktbreaklabel) then
               begin
                 aktcontinuelabel:=oldaktcontinuelabel;
                 aktbreaklabel:=oldaktbreaklabel;
               end;
           end;

         emitlab(nextonlabel);
         flowcontrol:=oldflowcontrol+flowcontrol;
         { next on node }
         if assigned(left) then
           begin
              cleartempgen;
              secondpass(left);
           end;
      end;

{*****************************************************************************
                             SecondTryFinally
*****************************************************************************}

    procedure ti386tryfinallynode.pass_2;
      var
         reraiselabel,
         finallylabel,
         endfinallylabel,
         exitfinallylabel,
         continuefinallylabel,
         breakfinallylabel,
         oldaktexitlabel,
         oldaktexit2label,
         oldaktcontinuelabel,
         oldaktbreaklabel : tasmlabel;
         oldflowcontrol,tryflowcontrol : tflowcontrol;
         decconst : longint;
         tempbuf,tempaddr : treference;

      begin
         { check if child nodes do a break/continue/exit }
         oldflowcontrol:=flowcontrol;
         flowcontrol:=[];
         { we modify EAX }
         usedinproc:=usedinproc or ($80 shr byte(R_EAX));
         getlabel(finallylabel);
         getlabel(endfinallylabel);
         getlabel(reraiselabel);

         { the finally block must catch break, continue and exit }
         { statements                                            }
         oldaktexitlabel:=aktexitlabel;
         oldaktexit2label:=aktexit2label;
         getlabel(exitfinallylabel);
         aktexitlabel:=exitfinallylabel;
         aktexit2label:=exitfinallylabel;
         if assigned(aktbreaklabel) then
          begin
            oldaktcontinuelabel:=aktcontinuelabel;
            oldaktbreaklabel:=aktbreaklabel;
            getlabel(breakfinallylabel);
            getlabel(continuefinallylabel);
            aktcontinuelabel:=continuefinallylabel;
            aktbreaklabel:=breakfinallylabel;
          end;

         gettempofsizereferencepersistant(12,tempaddr);
         gettempofsizereferencepersistant(24,tempbuf);
         emitpushreferenceaddr(tempaddr);
         emitpushreferenceaddr(tempbuf);
         push_int(1); { Type of stack-frame must be pushed}
         emitcall('FPC_PUSHEXCEPTADDR');

         { allocate eax }
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_PUSH,S_L,R_EAX);
         emitcall('FPC_SETJMP');
         emit_reg(A_PUSH,S_L,R_EAX);
         emit_reg_reg(A_TEST,S_L,R_EAX,R_EAX);
         { deallocate eax }
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         emitjmp(C_NE,finallylabel);

         { try code }
         if assigned(left) then
           begin
              secondpass(left);
              tryflowcontrol:=flowcontrol;
              if codegenerror then
                exit;
           end;

         emitlab(finallylabel);
         emitcall('FPC_POPADDRSTACK');
         ungetpersistanttempreference(tempaddr);
         ungetpersistanttempreference(tempbuf);

         { finally code }
         flowcontrol:=[];
         secondpass(right);
         if flowcontrol<>[] then
           CGMessage(cg_e_control_flow_outside_finally);
         if codegenerror then
           exit;
         { allocate eax }
         exprasmList.concat(Tairegalloc.Alloc(R_EAX));
         emit_reg(A_POP,S_L,R_EAX);
         emit_reg_reg(A_TEST,S_L,R_EAX,R_EAX);
         emitjmp(C_E,endfinallylabel);
         emit_reg(A_DEC,S_L,R_EAX);
         emitjmp(C_Z,reraiselabel);
         if fc_exit in tryflowcontrol then
           begin
              emit_reg(A_DEC,S_L,R_EAX);
              emitjmp(C_Z,oldaktexitlabel);
              decconst:=1;
           end
         else
           decconst:=2;
         if fc_break in tryflowcontrol then
           begin
              emit_const_reg(A_SUB,S_L,decconst,R_EAX);
              emitjmp(C_Z,oldaktbreaklabel);
              decconst:=1;
           end
         else
           inc(decconst);
         if fc_continue in tryflowcontrol then
           begin
              emit_const_reg(A_SUB,S_L,decconst,R_EAX);
              emitjmp(C_Z,oldaktcontinuelabel);
           end;
         { deallocate eax }
         exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
         emitlab(reraiselabel);
         emitcall('FPC_RERAISE');
         { do some magic for exit,break,continue in the try block }
         if fc_exit in tryflowcontrol then
           begin
              emitlab(exitfinallylabel);
              { allocate eax }
              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              emit_reg(A_POP,S_L,R_EAX);
              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              emit_const(A_PUSH,S_L,2);
              emitjmp(C_NONE,finallylabel);
           end;
         if fc_break in tryflowcontrol then
          begin
             emitlab(breakfinallylabel);
             { allocate eax }
             exprasmList.concat(Tairegalloc.Alloc(R_EAX));
             emit_reg(A_POP,S_L,R_EAX);
             { deallocate eax }
             exprasmList.concat(Tairegalloc.DeAlloc(R_EAX));
             emit_const(A_PUSH,S_L,3);
             emitjmp(C_NONE,finallylabel);
           end;
         if fc_continue in tryflowcontrol then
           begin
              emitlab(continuefinallylabel);
              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              emit_reg(A_POP,S_L,R_EAX);
              exprasmList.concat(Tairegalloc.Alloc(R_EAX));
              emit_const(A_PUSH,S_L,4);
              emitjmp(C_NONE,finallylabel);
           end;

         emitlab(endfinallylabel);

         aktexitlabel:=oldaktexitlabel;
         aktexit2label:=oldaktexit2label;
         if assigned(aktbreaklabel) then
          begin
            aktcontinuelabel:=oldaktcontinuelabel;
            aktbreaklabel:=oldaktbreaklabel;
          end;
         flowcontrol:=oldflowcontrol+tryflowcontrol;
      end;


{*****************************************************************************
                             SecondFail
*****************************************************************************}

    procedure ti386failnode.pass_2;
      begin
        emitjmp(C_None,faillabel);
      end;


begin
   cwhilerepeatnode:=ti386whilerepeatnode;
   cifnode:=ti386ifnode;
   cfornode:=ti386fornode;
   cexitnode:=ti386exitnode;
   cbreaknode:=ti386breaknode;
   ccontinuenode:=ti386continuenode;
   cgotonode:=ti386gotonode;
   clabelnode:=ti386labelnode;
   craisenode:=ti386raisenode;
   ctryexceptnode:=ti386tryexceptnode;
   ctryfinallynode:=ti386tryfinallynode;
   connode:=ti386onnode;
   cfailnode:=ti386failnode;
end.
{
  $Log$
  Revision 1.13  2001-07-01 20:16:20  peter
    * alignmentinfo record added
    * -Oa argument supports more alignment settings that can be specified
      per type: PROC,LOOP,VARMIN,VARMAX,CONSTMIN,CONSTMAX,RECORDMIN
      RECORDMAX,LOCALMIN,LOCALMAX. It is possible to set the mimimum
      required alignment and the maximum usefull alignment. The final
      alignment will be choosen per variable size dependent on these
      settings

  Revision 1.12  2001/04/15 09:48:31  peter
    * fixed crash in labelnode
    * easier detection of goto and label in try blocks

  Revision 1.11  2001/04/14 14:07:11  peter
    * moved more code from pass_1 to det_resulttype

  Revision 1.10  2001/04/13 01:22:19  peter
    * symtable change to classes
    * range check generation and errors fixed, make cycle DEBUG=1 works
    * memory leaks fixed

  Revision 1.9  2001/04/02 21:20:37  peter
    * resulttype rewrite

  Revision 1.8  2001/01/27 21:29:35  florian
     * behavior -Oa optimized

  Revision 1.7  2001/01/06 23:35:05  jonas
    * fixed webbug 1323

  Revision 1.6  2001/01/05 17:36:58  florian
  * the info about exception frames is stored now on the stack
  instead on the heap

  Revision 1.5  2000/12/25 00:07:32  peter
    + new tlinkedlist class (merge of old tstringqueue,tcontainer and
      tlinkedlist objects)

  Revision 1.4  2000/12/05 11:44:33  jonas
    + new integer regvar handling, should be much more efficient

  Revision 1.3  2000/11/29 00:30:47  florian
    * unused units removed from uses clause
    * some changes for widestrings

  Revision 1.2  2000/10/31 22:02:56  peter
    * symtable splitted, no real code changes

  Revision 1.1  2000/10/15 09:33:31  peter
    * moved n386*.pas to i386/ cpu_target dir

  Revision 1.1  2000/10/14 10:14:48  peter
    * moehrendorf oct 2000 rewrite

}