freepascal.compiler/compiler/tcmem.pas

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

    Type checking and register allocation for memory related 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 tcmem;
interface

    uses
      tree;

    procedure firstloadvmt(var p : ptree);
    procedure firsthnew(var p : ptree);
    procedure firstnew(var p : ptree);
    procedure firsthdispose(var p : ptree);
    procedure firstsimplenewdispose(var p : ptree);
    procedure firstaddr(var p : ptree);
    procedure firstdoubleaddr(var p : ptree);
    procedure firstderef(var p : ptree);
    procedure firstsubscript(var p : ptree);
    procedure firstvec(var p : ptree);
    procedure firstself(var p : ptree);
    procedure firstwith(var p : ptree);


implementation

    uses
      globtype,systems,
      cobjects,verbose,globals,
      symconst,symtable,aasm,types,
      htypechk,pass_1,cpubase
{$ifdef newcg}
      ,cgbase
{$else newcg}
      ,hcodegen
{$endif newcg}
      ;
{*****************************************************************************
                            FirstLoadVMT
*****************************************************************************}

    procedure firstloadvmt(var p : ptree);
      begin
         p^.registers32:=1;
         p^.location.loc:=LOC_REGISTER;
      end;


{*****************************************************************************
                             FirstHNew
*****************************************************************************}

    procedure firsthnew(var p : ptree);
      begin
      end;


{*****************************************************************************
                             FirstNewN
*****************************************************************************}

    procedure firstnew(var p : ptree);
      begin
         { Standardeinleitung }
         if assigned(p^.left) then
           firstpass(p^.left);

         if codegenerror then
           exit;
         if assigned(p^.left) then
           begin
              p^.registers32:=p^.left^.registers32;
              p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
              p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
           end;
         { result type is already set }
         procinfo^.flags:=procinfo^.flags or pi_do_call;
         if assigned(p^.left) then
           p^.location.loc:=LOC_REGISTER
         else
           p^.location.loc:=LOC_REFERENCE;
      end;


{*****************************************************************************
                            FirstDispose
*****************************************************************************}

    procedure firsthdispose(var p : ptree);
      begin
         firstpass(p^.left);

         if codegenerror then
           exit;

         p^.registers32:=p^.left^.registers32;
         p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
         if p^.registers32<1 then
           p^.registers32:=1;
         {
         if p^.left^.location.loc<>LOC_REFERENCE then
           CGMessage(cg_e_illegal_expression);
         }
         if p^.left^.location.loc=LOC_CREGISTER then
           inc(p^.registers32);
         p^.location.loc:=LOC_REFERENCE;
         p^.resulttype:=ppointerdef(p^.left^.resulttype)^.pointertype.def;
      end;


{*****************************************************************************
                        FirstSimpleNewDispose
*****************************************************************************}

    procedure firstsimplenewdispose(var p : ptree);
      begin
         { this cannot be in a register !! }
         make_not_regable(p^.left);

         firstpass(p^.left);
         if codegenerror then
          exit;

         { check the type }
         if p^.left^.resulttype=nil then
          p^.left^.resulttype:=generrordef;
         if (p^.left^.resulttype^.deftype<>pointerdef) then
           CGMessage1(type_e_pointer_type_expected,p^.left^.resulttype^.typename);

         if (p^.left^.location.loc<>LOC_REFERENCE) {and
            (p^.left^.location.loc<>LOC_CREGISTER)} then
           CGMessage(cg_e_illegal_expression);

         p^.registers32:=p^.left^.registers32;
         p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
         p^.resulttype:=voiddef;
         procinfo^.flags:=procinfo^.flags or pi_do_call;
      end;


{*****************************************************************************
                             FirstAddr
*****************************************************************************}

    procedure firstaddr(var p : ptree);
      var
         hp  : ptree;
         hp2 : pparaitem;
         hp3 : pabstractprocdef;
      begin
         make_not_regable(p^.left);
         if not(assigned(p^.resulttype)) then
           begin
              { tp @procvar support (type of @procvar is a void pointer)
                Note: we need to leave the addrn in the tree,
                else we can't see the difference between @procvar and procvar.
                we set the procvarload flag so a secondpass does nothing for
                this node (PFV) }
              if (m_tp_procvar in aktmodeswitches) then
               begin
                 hp:=p^.left;
                 case hp^.treetype of
                   calln :
                     begin
                       { is it a procvar? }
                       hp:=hp^.right;
                       if assigned(hp) then
                         begin
                           { remove calln node }
                           putnode(p^.left);
                           p^.left:=hp;
                           firstpass(hp);
                           p^.procvarload:=true;
                         end;
                     end;
                   loadn,
                   subscriptn,
                   typeconvn,
                   vecn,
                   derefn :
                     begin
                       firstpass(hp);
                       if codegenerror then
                        exit;
                       if hp^.resulttype^.deftype=procvardef then
                        begin
                          p^.procvarload:=true;
                        end;
                     end;
                 end;
               end;
              if p^.procvarload then
               begin
                 p^.registers32:=p^.left^.registers32;
                 p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
                 p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
                 if p^.registers32<1 then
                   p^.registers32:=1;
                 p^.location.loc:=p^.left^.location.loc;
                 p^.resulttype:=voidpointerdef;
                 exit;
               end;

              { proc 2 procvar ? }
              if p^.left^.treetype=calln then
                begin
                  { generate a methodcallnode or proccallnode }
                  { we shouldn't convert things like @tcollection.load }
                  if (p^.left^.symtableprocentry^.owner^.symtabletype=objectsymtable) and
                    not(assigned(p^.left^.methodpointer) and (p^.left^.methodpointer^.treetype=typen)) then
                   begin
                     hp:=genloadmethodcallnode(pprocsym(p^.left^.symtableprocentry),p^.left^.symtableproc,
                       getcopy(p^.left^.methodpointer));
                     disposetree(p);
                     firstpass(hp);
                     p:=hp;
                     exit;
                   end
                  else
                   hp:=genloadcallnode(pprocsym(p^.left^.symtableprocentry),p^.left^.symtableproc);

                  { result is a procedure variable }
                  { No, to be TP compatible, you must return a pointer to
                    the procedure that is stored in the procvar.}
                  if not(m_tp_procvar in aktmodeswitches) then
                    begin
                       p^.resulttype:=new(pprocvardef,init);

                    { it could also be a procvar, not only pprocsym ! }
                       if p^.left^.symtableprocentry^.typ=varsym then
                        hp3:=pabstractprocdef(pvarsym(p^.left^.symtableentry)^.vartype.def)
                       else
                        hp3:=pabstractprocdef(pprocsym(p^.left^.symtableprocentry)^.definition);

                       pprocvardef(p^.resulttype)^.proctypeoption:=hp3^.proctypeoption;
                       pprocvardef(p^.resulttype)^.proccalloptions:=hp3^.proccalloptions;
                       pprocvardef(p^.resulttype)^.procoptions:=hp3^.procoptions;
                       pprocvardef(p^.resulttype)^.rettype:=hp3^.rettype;
                       pprocvardef(p^.resulttype)^.symtablelevel:=hp3^.symtablelevel;

                     { method ? then set the methodpointer flag }
                       if (hp3^.owner^.symtabletype=objectsymtable) and
                          (pobjectdef(hp3^.owner^.defowner)^.is_class) then
{$ifdef INCLUDEOK}
                         include(pprocvardef(p^.resulttype)^.procoptions,po_methodpointer);
{$else}
                         pprocvardef(p^.resulttype)^.procoptions:=pprocvardef(p^.resulttype)^.procoptions+[po_methodpointer];
{$endif}
                       { we need to process the parameters reverse so they are inserted
                         in the correct right2left order (PFV) }
                       hp2:=pparaitem(hp3^.para^.last);
                       while assigned(hp2) do
                         begin
                            pprocvardef(p^.resulttype)^.concatpara(hp2^.paratype,hp2^.paratyp);
                            hp2:=pparaitem(hp2^.previous);
                         end;
                    end
                  else
                    p^.resulttype:=voidpointerdef;

                  disposetree(p^.left);
                  p^.left:=hp;
                end
              else
                begin
                  firstpass(p^.left);
                  { what are we getting the address from an absolute sym? }
                  hp:=p^.left;
                  while assigned(hp) and (hp^.treetype in [vecn,derefn,subscriptn]) do
                   hp:=hp^.left;
                  if assigned(hp) and (hp^.treetype=loadn) and
                     ((hp^.symtableentry^.typ=absolutesym) and
                      pabsolutesym(hp^.symtableentry)^.absseg) then
                   begin
                     if not(cs_typed_addresses in aktlocalswitches) then
                       p^.resulttype:=voidfarpointerdef
                     else
                       p^.resulttype:=new(ppointerdef,initfardef(p^.left^.resulttype));
                   end
                  else
                   begin
                     if not(cs_typed_addresses in aktlocalswitches) then
                       p^.resulttype:=voidpointerdef
                     else
                       p^.resulttype:=new(ppointerdef,initdef(p^.left^.resulttype));
                   end;
                end;
           end;
         firstpass(p^.left);
         { this is like the function addr }
         inc(parsing_para_level);
         set_varstate(p^.left,false);
         dec(parsing_para_level);
         if codegenerror then
           exit;

         { don't allow constants }
         if is_constnode(p^.left) then
          begin
            aktfilepos:=p^.left^.fileinfo;
            CGMessage(type_e_no_addr_of_constant);
          end
         else
           begin
             { we should allow loc_mem for @string }
             if not(p^.left^.location.loc in [LOC_MEM,LOC_REFERENCE]) then
               begin
                 aktfilepos:=p^.left^.fileinfo;
                 CGMessage(cg_e_illegal_expression);
               end;
           end;

         p^.registers32:=p^.left^.registers32;
         p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
         if p^.registers32<1 then
           p^.registers32:=1;
         { is this right for object of methods ?? }
         p^.location.loc:=LOC_REGISTER;
      end;


{*****************************************************************************
                           FirstDoubleAddr
*****************************************************************************}

    procedure firstdoubleaddr(var p : ptree);
      begin
         make_not_regable(p^.left);
         firstpass(p^.left);
         inc(parsing_para_level);
         set_varstate(p^.left,false);
         dec(parsing_para_level);
         if p^.resulttype=nil then
           p^.resulttype:=voidpointerdef;
         if codegenerror then
           exit;

         if (p^.left^.resulttype^.deftype)<>procvardef then
           CGMessage(cg_e_illegal_expression);

         if (p^.left^.location.loc<>LOC_REFERENCE) then
           CGMessage(cg_e_illegal_expression);

         p^.registers32:=p^.left^.registers32;
         p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
         if p^.registers32<1 then
           p^.registers32:=1;
         p^.location.loc:=LOC_REGISTER;
      end;


{*****************************************************************************
                             FirstDeRef
*****************************************************************************}

    procedure firstderef(var p : ptree);
      begin
         firstpass(p^.left);
         set_varstate(p^.left,true);
         if codegenerror then
           begin
             p^.resulttype:=generrordef;
             exit;
           end;

         p^.registers32:=max(p^.left^.registers32,1);
         p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}

         if p^.left^.resulttype^.deftype<>pointerdef then
          CGMessage(cg_e_invalid_qualifier);

         p^.resulttype:=ppointerdef(p^.left^.resulttype)^.pointertype.def;
         p^.location.loc:=LOC_REFERENCE;
      end;


{*****************************************************************************
                            FirstSubScript
*****************************************************************************}

    procedure firstsubscript(var p : ptree);
      begin
         firstpass(p^.left);
         if codegenerror then
           begin
             p^.resulttype:=generrordef;
             exit;
           end;
         p^.resulttype:=p^.vs^.vartype.def;

         p^.registers32:=p^.left^.registers32;
         p^.registersfpu:=p^.left^.registersfpu;
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=p^.left^.registersmmx;
{$endif SUPPORT_MMX}
         { classes must be dereferenced implicit }
         if (p^.left^.resulttype^.deftype=objectdef) and
           pobjectdef(p^.left^.resulttype)^.is_class then
           begin
              if p^.registers32=0 then
                p^.registers32:=1;
              p^.location.loc:=LOC_REFERENCE;
           end
         else
           begin
              if (p^.left^.location.loc<>LOC_MEM) and
                (p^.left^.location.loc<>LOC_REFERENCE) then
                CGMessage(cg_e_illegal_expression);
              set_location(p^.location,p^.left^.location);
           end;
      end;


{*****************************************************************************
                               FirstVec
*****************************************************************************}

    procedure firstvec(var p : ptree);
      var
         harr : pdef;
         ct : tconverttype;
{$ifdef consteval}
         tcsym : ptypedconstsym;
{$endif}
      begin
         firstpass(p^.left);
         firstpass(p^.right);
         if codegenerror then
           exit;

         { range check only for arrays }
         if (p^.left^.resulttype^.deftype=arraydef) then
           begin
              if (isconvertable(p^.right^.resulttype,parraydef(p^.left^.resulttype)^.rangetype.def,
                    ct,ordconstn,false)=0) and
                 not(is_equal(p^.right^.resulttype,parraydef(p^.left^.resulttype)^.rangetype.def)) then
                CGMessage(type_e_mismatch);
           end;
         { Never convert a boolean or a char !}
         { maybe type conversion }
         if (p^.right^.resulttype^.deftype<>enumdef) and
            not(is_char(p^.right^.resulttype)) and
            not(is_boolean(p^.right^.resulttype)) then
           begin
             p^.right:=gentypeconvnode(p^.right,s32bitdef);
             firstpass(p^.right);
             if codegenerror then
              exit;
           end;

         { are we accessing a pointer[], then convert the pointer to
           an array first }
         if (p^.left^.resulttype^.deftype=pointerdef) then
           begin
             { convert pointer to array }
             harr:=new(parraydef,init(0,$7fffffff,s32bitdef));
             parraydef(harr)^.elementtype.def:=ppointerdef(p^.left^.resulttype)^.pointertype.def;
             p^.left:=gentypeconvnode(p^.left,harr);
             firstpass(p^.left);
             if codegenerror then
               exit;
             p^.resulttype:=parraydef(harr)^.elementtype.def
           end;

         { determine return type }
         if not assigned(p^.resulttype) then
           if p^.left^.resulttype^.deftype=arraydef then
             p^.resulttype:=parraydef(p^.left^.resulttype)^.elementtype.def
           else if p^.left^.resulttype^.deftype=stringdef then
             begin
                { indexed access to strings }
                case pstringdef(p^.left^.resulttype)^.string_typ of
                   {
                   st_widestring : p^.resulttype:=cwchardef;
                   }
                   st_ansistring : p^.resulttype:=cchardef;
                   st_longstring : p^.resulttype:=cchardef;
                   st_shortstring : p^.resulttype:=cchardef;
                end;
             end
           else
             CGMessage(type_e_mismatch);
         { the register calculation is easy if a const index is used }
         if p^.right^.treetype=ordconstn then
           begin
{$ifdef consteval}
              { constant evaluation }
              if (p^.left^.treetype=loadn) and
                 (p^.left^.symtableentry^.typ=typedconstsym) then
               begin
                 tcsym:=ptypedconstsym(p^.left^.symtableentry);
                 if tcsym^.defintion^.typ=stringdef then
                  begin

                  end;
               end;
{$endif}
              p^.registers32:=p^.left^.registers32;

              { for ansi/wide strings, we need at least one register }
              if is_ansistring(p^.left^.resulttype) or
                is_widestring(p^.left^.resulttype) then
                p^.registers32:=max(p^.registers32,1);
           end
         else
           begin
              { this rules are suboptimal, but they should give }
              { good results                                }
              p^.registers32:=max(p^.left^.registers32,p^.right^.registers32);

              { for ansi/wide strings, we need at least one register }
              if is_ansistring(p^.left^.resulttype) or
                is_widestring(p^.left^.resulttype) then
                p^.registers32:=max(p^.registers32,1);

              { need we an extra register when doing the restore ? }
              if (p^.left^.registers32<=p^.right^.registers32) and
              { only if the node needs less than 3 registers }
              { two for the right node and one for the       }
              { left address                             }
                (p^.registers32<3) then
                inc(p^.registers32);

              { need we an extra register for the index ? }
              if (p^.right^.location.loc<>LOC_REGISTER)
              { only if the right node doesn't need a register }
                and (p^.right^.registers32<1) then
                inc(p^.registers32);

              { not correct, but what works better ?
              if p^.left^.registers32>0 then
                p^.registers32:=max(p^.registers32,2)
              else
                 min. one register
                p^.registers32:=max(p^.registers32,1);
              }
           end;
         p^.registersfpu:=max(p^.left^.registersfpu,p^.right^.registersfpu);
{$ifdef SUPPORT_MMX}
         p^.registersmmx:=max(p^.left^.registersmmx,p^.right^.registersmmx);
{$endif SUPPORT_MMX}
         if p^.left^.location.loc in [LOC_CREGISTER,LOC_REFERENCE] then
           p^.location.loc:=LOC_REFERENCE
         else
           p^.location.loc:=LOC_MEM;
      end;


{*****************************************************************************
                               FirstSelf
*****************************************************************************}

    procedure firstself(var p : ptree);
      begin
         if (p^.resulttype^.deftype=classrefdef) or
           ((p^.resulttype^.deftype=objectdef)
             and pobjectdef(p^.resulttype)^.is_class
           ) then
           p^.location.loc:=LOC_CREGISTER
         else
           p^.location.loc:=LOC_REFERENCE;
      end;


{*****************************************************************************
                               FirstWithN
*****************************************************************************}

    procedure firstwith(var p : ptree);
      var
         symtable : pwithsymtable;
         i : longint;
      begin
         if assigned(p^.left) and assigned(p^.right) then
            begin
               firstpass(p^.left);
               { is this correct ?  At least after is like if used
               set_varstate(p^.left,false);
                 already done in _with_statment }
               p^.left^.varstateset:=false;
               set_varstate(p^.left,true);
               if codegenerror then
                 exit;
               symtable:=p^.withsymtable;
               for i:=1 to p^.tablecount do
                 begin
                    if (p^.left^.treetype=loadn) and
                       (p^.left^.symtable=aktprocsym^.definition^.localst) then
                      symtable^.direct_with:=true;
                    symtable^.withnode:=p;
                    symtable:=pwithsymtable(symtable^.next);
                  end;
               firstpass(p^.right);
               if codegenerror then
                 exit;

               left_right_max(p);
               p^.resulttype:=voiddef;
            end
         else
           begin
              { optimization }
              disposetree(p);
              p:=nil;
           end;
      end;


end.
{
  $Log$
  Revision 1.2  2000-07-13 11:32:52  michael
  + removed logs

}