freepascal.compiler/compiler/parser.pas

{
    Copyright (c) 1998-2002 by Florian Klaempfl

    This unit does the parsing process

    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 parser;

{$i fpcdefs.inc}

interface

{$ifdef PREPROCWRITE}
    procedure preprocess(const filename:string);
{$endif PREPROCWRITE}
    procedure compile(const filename:string);
    procedure initparser;
    procedure doneparser;

implementation

    uses
{$IFNDEF MACOS_USE_FAKE_SYSUTILS}
      sysutils,
{$ENDIF MACOS_USE_FAKE_SYSUTILS}
      cutils,cclasses,
      globtype,version,tokens,systems,globals,verbose,
      symbase,symtable,symsym,
      finput,fmodule,fppu,
      aasmbase,aasmtai,
      cgbase,
      script,gendef,
{$ifdef BrowserCol}
      browcol,
{$endif BrowserCol}
{$ifdef BrowserLog}
      browlog,
{$endif BrowserLog}
      comphook,
      scanner,scandir,
      pbase,ptype,psystem,pmodules,psub,
      cresstr,cpuinfo,procinfo;


    procedure initparser;
      begin
         { ^M means a string or a char, because we don't parse a }
         { type declaration                                      }
         ignore_equal:=false;

         { we didn't parse a object or class declaration }
         { and no function header                        }
         testcurobject:=0;

         { Current compiled module/proc }
         objectlibrary:=nil;
         current_module:=nil;
         compiled_module:=nil;
         current_procinfo:=nil;
         SetCompileModule(nil);

         loaded_units:=TLinkedList.Create;

         usedunits:=TLinkedList.Create;

         { global switches }
         aktglobalswitches:=initglobalswitches;

         aktsourcecodepage:=initsourcecodepage;

         { initialize scanner }
         InitScanner;
         InitScannerDirectives;

         { scanner }
         c:=#0;
         pattern:='';
         orgpattern:='';
         current_scanner:=nil;

         { register all nodes and tais }
         registernodes;
         registertais;

         { memory sizes }
         if stacksize=0 then
           stacksize:=target_info.stacksize;

         { open assembler response }
         if cs_link_on_target in aktglobalswitches then
           GenerateAsmRes(outputexedir+inputfile+'_ppas')
         else
           GenerateAsmRes(outputexedir+'ppas');

         { open deffile }
         DefFile:=TDefFile.Create(outputexedir+inputfile+target_info.defext);

         { list of generated .o files, so the linker can remove them }
         SmartLinkOFiles:=TStringList.Create;

         { codegen }
         if paraprintnodetree<>0 then
           printnode_reset;

         { target specific stuff }
         case target_info.system of
           system_powerpc_amiga:
             include(supported_calling_conventions,pocall_syscall);
           system_powerpc_morphos:
             include(supported_calling_conventions,pocall_syscall);
           system_m68k_amiga:
             include(supported_calling_conventions,pocall_syscall);
         end;
      end;


    procedure doneparser;
      begin
         { Reset current compiling info, so destroy routines can't
           reference the data that might already be destroyed }
         objectlibrary:=nil;
         current_module:=nil;
         compiled_module:=nil;
         current_procinfo:=nil;
         SetCompileModule(nil);

         { unload units }
         if assigned(loaded_units) then
           begin
             loaded_units.free;
             loaded_units:=nil;
           end;
         if assigned(usedunits) then
           begin
             usedunits.free;
             usedunits:=nil;
           end;

         { if there was an error in the scanner, the scanner is
           still assinged }
         if assigned(current_scanner) then
          begin
            current_scanner.free;
            current_scanner:=nil;
          end;

         { close scanner }
         DoneScanner;

         { close ppas,deffile }
         asmres.free;
         deffile.free;

         { free list of .o files }
         SmartLinkOFiles.Free;
      end;




{$ifdef PREPROCWRITE}
    procedure preprocess(const filename:string);
      var
        i : longint;
      begin
         new(preprocfile,init('pre'));
       { initialize a module }
         current_module:=new(pmodule,init(filename,false));

         macrosymtablestack:= initialmacrosymtable;
         current_module.localmacrosymtable:= tmacrosymtable.create(false);
         current_module.localmacrosymtable.next:= initialmacrosymtable;
         macrosymtablestack:= current_module.localmacrosymtable;

         main_module:=current_module;
       { startup scanner, and save in current_module }
         current_scanner:=new(pscannerfile,Init(filename));
         current_module.scanner:=current_scanner;
       { loop until EOF is found }
         repeat
           current_scanner^.readtoken(true);
           preprocfile^.AddSpace;
           case token of
             _ID :
               begin
                 preprocfile^.Add(orgpattern);
               end;
             _REALNUMBER,
             _INTCONST :
               preprocfile^.Add(pattern);
             _CSTRING :
               begin
                 i:=0;
                 while (i<length(pattern)) do
                  begin
                    inc(i);
                    if pattern[i]='''' then
                     begin
                       insert('''',pattern,i);
                       inc(i);
                     end;
                  end;
                 preprocfile^.Add(''''+pattern+'''');
               end;
             _CCHAR :
               begin
                 case pattern[1] of
                   #39 :
                     pattern:='''''''';
                   #0..#31,
                   #128..#255 :
                     begin
                       str(ord(pattern[1]),pattern);
                       pattern:='#'+pattern;
                     end;
                   else
                     pattern:=''''+pattern[1]+'''';
                 end;
                 preprocfile^.Add(pattern);
               end;
             _EOF :
               break;
             else
               preprocfile^.Add(tokeninfo^[token].str)
           end;
         until false;
       { free scanner }
         dispose(current_scanner,done);
         current_scanner:=nil;
       { close }
         dispose(preprocfile,done);
      end;
{$endif PREPROCWRITE}


{*****************************************************************************
                      Create information for a new module
*****************************************************************************}

    procedure init_module;
      var
        i : Tasmlist;
      begin
         exprasmlist:=taasmoutput.create;
         for i:=low(Tasmlist) to high(Tasmlist) do
           asmlist[i]:=Taasmoutput.create;

         { PIC data }
         if (target_info.system in [system_powerpc_darwin,system_i386_darwin]) then
           asmlist[al_picdata].concat(tai_directive.create(asd_non_lazy_symbol_pointer,''));

         { Resource strings }
         cresstr.resourcestrings:=Tresourcestrings.Create;

         { use the librarydata from current_module }
         objectlibrary:=current_module.librarydata;
      end;


    procedure done_module;
      var
{$ifdef MEMDEBUG}
        d : tmemdebug;
{$endif}
        i:Tasmlist;
      begin
{$ifdef MEMDEBUG}
         d:=tmemdebug.create(current_module.modulename^+' - asmlists');
{$endif}
         for i:=low(Tasmlist) to high(Tasmlist) do
           if asmlist[i]<>nil then
             asmlist[i].free;
{$ifdef MEMDEBUG}
         d.free;
{$endif}
         { resource strings }
         cresstr.resourcestrings.free;
         objectlibrary:=nil;
      end;


{*****************************************************************************
                             Compile a source file
*****************************************************************************}

    procedure compile(const filename:string);
      type
        polddata=^tolddata;
        tolddata=record
        { scanner }
          oldidtoken,
          oldtoken       : ttoken;
          oldtokenpos    : tfileposinfo;
          oldc           : char;
          oldpattern,
          oldorgpattern  : string;
          old_block_type : tblock_type;
        { symtable }
          oldsymtablestack,
          oldmacrosymtablestack : tsymtablestack;
          oldaktprocsym    : tprocsym;
        { cg }
          oldparse_only  : boolean;
        { asmlists }
          oldexprasmlist:Taasmoutput;
          oldasmlist:array[Tasmlist] of Taasmoutput;
          oldobjectlibrary : TObjLibraryData;
        { al_resourcestrings }
          Oldresourcestrings : tresourcestrings;
        { akt.. things }
          oldaktlocalswitches  : tlocalswitches;
          oldaktmoduleswitches : tmoduleswitches;
          oldaktfilepos      : tfileposinfo;
          oldaktpackrecords,
          oldaktpackenum       : shortint;
          oldaktmaxfpuregisters : longint;
          oldaktalignment  : talignmentinfo;
          oldaktspecificoptprocessor,
          oldaktoptprocessor : tprocessors;
          oldaktfputype      : tfputype;
          oldaktasmmode      : tasmmode;
          oldaktinterfacetype: tinterfacetypes;
          oldaktmodeswitches : tmodeswitches;
          old_compiled_module : tmodule;
          oldcurrent_procinfo : tprocinfo;
          oldaktdefproccall : tproccalloption;
          oldsourcecodepage : tcodepagestring;
        end;

      var
         olddata : polddata;
       begin
         inc(compile_level);
         parser_current_file:=filename;
         { Uses heap memory instead of placing everything on the
           stack. This is needed because compile() can be called
           recursively }
         new(olddata);
         with olddata^ do
          begin
            old_compiled_module:=compiled_module;
          { save symtable state }
            oldsymtablestack:=symtablestack;
            oldmacrosymtablestack:=macrosymtablestack;
            oldcurrent_procinfo:=current_procinfo;
            oldaktdefproccall:=aktdefproccall;
          { save scanner state }
            oldc:=c;
            oldpattern:=pattern;
            oldorgpattern:=orgpattern;
            oldtoken:=token;
            oldidtoken:=idtoken;
            old_block_type:=block_type;
            oldtokenpos:=akttokenpos;
            oldsourcecodepage:=aktsourcecodepage;
          { save cg }
            oldparse_only:=parse_only;
          { save assembler lists }
            oldasmlist:=asmlist;
            oldexprasmlist:=exprasmlist;
            oldobjectlibrary:=objectlibrary;
            Oldresourcestrings:=resourcestrings;
          { save akt... state }
          { handle the postponed case first }
           if localswitcheschanged then
             begin
               aktlocalswitches:=nextaktlocalswitches;
               localswitcheschanged:=false;
             end;
            oldaktlocalswitches:=aktlocalswitches;
            oldaktmoduleswitches:=aktmoduleswitches;
            oldaktalignment:=aktalignment;
            oldaktpackenum:=aktpackenum;
            oldaktpackrecords:=aktpackrecords;
            oldaktfputype:=aktfputype;
            oldaktmaxfpuregisters:=aktmaxfpuregisters;
            oldaktoptprocessor:=aktoptprocessor;
            oldaktspecificoptprocessor:=aktspecificoptprocessor;
            oldaktasmmode:=aktasmmode;
            oldaktinterfacetype:=aktinterfacetype;
            oldaktfilepos:=aktfilepos;
            oldaktmodeswitches:=aktmodeswitches;
          end;
       { reset parser, a previous fatal error could have left these variables in an unreliable state, this is
         important for the IDE }
         afterassignment:=false;
         in_args:=false;
         got_addrn:=false;
         getprocvardef:=nil;

       { show info }
         Message1(parser_i_compiling,filename);

       { reset symtable }
         symtablestack:=tsymtablestack.create;
         macrosymtablestack:=tsymtablestack.create;
         systemunit:=nil;
         aktdefproccall:=initdefproccall;
         aktexceptblock:=0;
         exceptblockcounter:=0;
         aktmaxfpuregisters:=-1;
       { reset the unit or create a new program }
         { a unit compiled at command line must be inside the loaded_unit list }
         if (compile_level=1) then
           begin
             if assigned(current_module) then
               internalerror(200501158);
             current_module:=tppumodule.create(nil,filename,'',false);
             addloadedunit(current_module);
             main_module:=current_module;
             current_module.state:=ms_compile;
           end;
         if not(assigned(current_module) and
                (current_module.state in [ms_compile,ms_second_compile])) then
           internalerror(200212281);

         { Set the module to use for verbose }
         compiled_module:=current_module;
         SetCompileModule(current_module);
         Fillchar(aktfilepos,0,sizeof(aktfilepos));

         { Load current state from the init values }
         aktlocalswitches:=initlocalswitches;
         aktmoduleswitches:=initmoduleswitches;
         aktmodeswitches:=initmodeswitches;
         {$IFDEF Testvarsets}
         aktsetalloc:=initsetalloc;
         {$ENDIF}
         aktalignment:=initalignment;
         aktfputype:=initfputype;
         aktpackenum:=initpackenum;
         aktpackrecords:=0;
         aktoptprocessor:=initoptprocessor;
         aktspecificoptprocessor:=initspecificoptprocessor;
         aktasmmode:=initasmmode;
         aktinterfacetype:=initinterfacetype;

         { startup scanner and load the first file }
         current_scanner:=tscannerfile.Create(filename);
         current_scanner.firstfile;
         current_module.scanner:=current_scanner;

         { init macros before anything in the file is parsed.}
         current_module.localmacrosymtable:= tmacrosymtable.create(false);
         macrosymtablestack.push(initialmacrosymtable);
         macrosymtablestack.push(current_module.localmacrosymtable);

         { read the first token }
         current_scanner.readtoken(false);

         { init code generator for a new module }
         init_module;

         { If the compile level > 1 we get a nice "unit expected" error
           message if we are trying to use a program as unit.}
         try
           try
             if (token=_UNIT) or (compile_level>1) then
               begin
                 current_module.is_unit:=true;
                 proc_unit;
               end
             else
               proc_program(token=_LIBRARY);
           except
             on ECompilerAbort do
               raise;
             on Exception do
               begin
                 { Increase errorcounter to prevent some
                   checks during cleanup }
                 inc(status.errorcount);
                 raise;
               end;
           end;
         finally
           { restore old state }
           done_module;

           if assigned(current_module) then
             begin
               { module is now compiled }
               tppumodule(current_module).state:=ms_compiled;

               { free ppu }
               if assigned(tppumodule(current_module).ppufile) then
                 begin
                   tppumodule(current_module).ppufile.free;
                   tppumodule(current_module).ppufile:=nil;
                 end;

               { free scanner }
               if assigned(current_module.scanner) then
                 begin
                   if current_scanner=tscannerfile(current_module.scanner) then
                     current_scanner:=nil;
                   tscannerfile(current_module.scanner).free;
                   current_module.scanner:=nil;
                 end;

               { free symtable stack }
               if assigned(symtablestack) then
                 begin
                   symtablestack.free;
                   symtablestack:=nil;
                 end;
               if assigned(macrosymtablestack) then
                 begin
                   macrosymtablestack.free;
                   macrosymtablestack:=nil;
                 end;
             end;

            with olddata^ do
              begin
                { restore scanner }
                c:=oldc;
                pattern:=oldpattern;
                orgpattern:=oldorgpattern;
                token:=oldtoken;
                idtoken:=oldidtoken;
                akttokenpos:=oldtokenpos;
                block_type:=old_block_type;
                { restore cg }
                parse_only:=oldparse_only;
                { restore asmlists }
                exprasmlist:=oldexprasmlist;
                asmlist:=oldasmlist;
                { object data }
                resourcestrings:=oldresourcestrings;
                objectlibrary:=oldobjectlibrary;
                { restore previous scanner }
                if assigned(old_compiled_module) then
                  current_scanner:=tscannerfile(old_compiled_module.scanner)
                else
                  current_scanner:=nil;
                if assigned(current_scanner) then
                  parser_current_file:=current_scanner.inputfile.name^;
                { restore symtable state }
                symtablestack:=oldsymtablestack;
                macrosymtablestack:=oldmacrosymtablestack;
                aktdefproccall:=oldaktdefproccall;
                current_procinfo:=oldcurrent_procinfo;
                aktsourcecodepage:=oldsourcecodepage;
                aktlocalswitches:=oldaktlocalswitches;
                aktmoduleswitches:=oldaktmoduleswitches;
                aktalignment:=oldaktalignment;
                aktpackenum:=oldaktpackenum;
                aktpackrecords:=oldaktpackrecords;
                aktmaxfpuregisters:=oldaktmaxfpuregisters;
                aktoptprocessor:=oldaktoptprocessor;
                aktspecificoptprocessor:=oldaktspecificoptprocessor;
                aktfputype:=oldaktfputype;
                aktasmmode:=oldaktasmmode;
                aktinterfacetype:=oldaktinterfacetype;
                aktfilepos:=oldaktfilepos;
                aktmodeswitches:=oldaktmodeswitches;
                aktexceptblock:=0;
                exceptblockcounter:=0;
              end;
            { Shut down things when the last file is compiled succesfull }
            if (compile_level=1) and
                (status.errorcount=0) then
              begin
                parser_current_file:='';
                { Close script }
                if (not AsmRes.Empty) then
                begin
                  Message1(exec_i_closing_script,AsmRes.Fn);
                  AsmRes.WriteToDisk;
                end;

                { do not create browsers on errors !! }
                if status.errorcount=0 then
                begin
{$ifdef BrowserLog}
                  { Write Browser Log }
                  if (cs_browser_log in aktglobalswitches) and
                      (cs_browser in aktmoduleswitches) then
                    begin
                      if browserlog.elements_to_list.empty then
                      begin
                        Message1(parser_i_writing_browser_log,browserlog.Fname);
                        WriteBrowserLog;
                      end
                      else
                      browserlog.list_elements;
                    end;
{$endif BrowserLog}
                  { Write Browser Collections, also used by the TextMode IDE to
                    retrieve a list of sourcefiles }
                  do_extractsymbolinfo{$ifdef FPC}(){$endif};
                end;
              end;

           dec(compile_level);
           compiled_module:=olddata^.old_compiled_module;
           SetCompileModule(compiled_module);

           dispose(olddata);
         end;
    end;

end.