{
    $Id$
    Copyright (c) 1998-2002 by Florian Klaempfl

    This unit exports some help routines for the code generation

    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 cgbase;

{$i fpcdefs.inc}

  interface

    uses
      { common }
      cclasses,
      { global }
      globals,verbose,
      { symtable }
      symconst,symtype,symdef,symsym,
      { aasm }
      cpubase,cpuinfo,cginfo,aasmbase,aasmtai
      ;



    const
       {# bitmask indicating if the procedure uses asm }
       pi_uses_asm  = $1;
       {# bitmask indicating if the procedure is exported by an unit }
       pi_is_global = $2;
       {# bitmask indicating if the procedure does a call }
       pi_do_call   = $4;
       {# bitmask indicating if the procedure is an operator   }
       pi_operator  = $8;
       {# bitmask indicating if the procedure is an external C function }
       pi_c_import  = $10;
       {# bitmask indicating if the procedure has a try statement = no register optimization }
       pi_uses_exceptions = $20;
       {# bitmask indicating if the procedure is declared as @var(assembler), don't optimize}
       pi_is_assembler = $40;
       {# bitmask indicating if the procedure contains data which needs to be finalized }
       pi_needs_implicit_finally = $80;

    type
       pprocinfo = ^tprocinfo;
       tprocinfo = object
          {# pointer to parent in nested procedures }
          parent : pprocinfo;
          {# current class, if we are in a method }
          _class : tobjectdef;
          {# the definition of the routine itself }
          procdef : tprocdef;
          {# frame pointer offset??? }
          framepointer_offset : longint;
          { self pointer offset???? }
          selfpointer_offset : longint;
          {# result value offset in stack (functions only) }
          return_offset : longint;
          {# firsttemp position }
          firsttemp_offset : longint;
          {# parameter offset in stack }
          para_offset : longint;

          {# some collected informations about the procedure
             see pi_xxxx above                               }
          flags : longint;

          {# register used as frame pointer }
          framepointer : tregister;

          {# true, if the procedure is exported by a unit }
          globalsymbol : boolean;

          {# true, if the procedure should be exported (only OS/2) }
          exported : boolean;

          {# true, if we can not use fast exit code }
          no_fast_exit : boolean;

          aktproccode,aktentrycode,
          aktexitcode,aktlocaldata : taasmoutput;
          constructor init;
          destructor done;
       end;

       pregvarinfo = ^tregvarinfo;
       tregvarinfo = record
          regvars : array[1..maxvarregs] of tvarsym;
          regvars_para : array[1..maxvarregs] of boolean;
          regvars_refs : array[1..maxvarregs] of longint;

          fpuregvars : array[1..maxfpuvarregs] of tvarsym;
          fpuregvars_para : array[1..maxfpuvarregs] of boolean;
          fpuregvars_refs : array[1..maxfpuvarregs] of longint;
       end;


    var
       {# information about the current sub routine being parsed (@var(pprocinfo))}
       procinfo : pprocinfo;

       { labels for BREAK and CONTINUE }
       aktbreaklabel,aktcontinuelabel : tasmlabel;

       { label when the result is true or false }
       truelabel,falselabel : tasmlabel;

       { label to leave the sub routine }
       aktexitlabel : tasmlabel;

       { also an exit label, only used we need to clear only the stack }
       aktexit2label : tasmlabel;

       {# only used in constructor for fail keyword or if getmem fails }
       faillabel      : tasmlabel;
       quickexitlabel : tasmlabel;

       {# true, if there was an error while code generation occurs }
       codegenerror : boolean;

       { save the size of pushed parameter, needed for aligning }
       pushedparasize : longint;


    { message calls with codegenerror support }
    procedure cgmessage(t : longint);
    procedure cgmessage1(t : longint;const s : string);
    procedure cgmessage2(t : longint;const s1,s2 : string);
    procedure cgmessage3(t : longint;const s1,s2,s3 : string);
    procedure CGMessagePos(const pos:tfileposinfo;t:longint);
    procedure CGMessagePos1(const pos:tfileposinfo;t:longint;const s1:string);
    procedure CGMessagePos2(const pos:tfileposinfo;t:longint;const s1,s2:string);
    procedure CGMessagePos3(const pos:tfileposinfo;t:longint;const s1,s2,s3:string);

    { initialize respectively terminates the code generator }
    { for a new module or procedure                      }
    procedure codegen_doneprocedure;
    procedure codegen_donemodule;
    procedure codegen_newmodule;
    procedure codegen_newprocedure;

    {# From a definition return the abstract code generator size (@var(tcgsize) enum). It is
       to note that the value returned can be @var(OS_NO) }
    function def_cgsize(def: tdef): tcgsize;
    function int_cgsize(const l: aword): tcgsize;

    {# return the inverse condition of opcmp }
    function inverse_opcmp(opcmp: topcmp): topcmp;

    {# return whether op is commutative }
    function commutativeop(op: topcg): boolean;


implementation

     uses
        systems,
        cresstr,
        defbase
{$ifdef fixLeaksOnError}
        ,comphook
{$endif fixLeaksOnError}

        ;

{$ifdef fixLeaksOnError}
     var procinfoStack: TStack;
         hcodegen_old_do_stop: tstopprocedure;
{$endif fixLeaksOnError}

{*****************************************************************************
            override the message calls to set codegenerror
*****************************************************************************}

    procedure cgmessage(t : longint);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.Message(t);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;

    procedure cgmessage1(t : longint;const s : string);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.Message1(t,s);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;

    procedure cgmessage2(t : longint;const s1,s2 : string);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.Message2(t,s1,s2);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;

    procedure cgmessage3(t : longint;const s1,s2,s3 : string);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.Message3(t,s1,s2,s3);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;


    procedure cgmessagepos(const pos:tfileposinfo;t : longint);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.MessagePos(pos,t);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;

    procedure cgmessagepos1(const pos:tfileposinfo;t : longint;const s1 : string);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.MessagePos1(pos,t,s1);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;

    procedure cgmessagepos2(const pos:tfileposinfo;t : longint;const s1,s2 : string);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.MessagePos2(pos,t,s1,s2);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;

    procedure cgmessagepos3(const pos:tfileposinfo;t : longint;const s1,s2,s3 : string);
      var
         olderrorcount : longint;
      begin
         if not(codegenerror) then
           begin
              olderrorcount:=Errorcount;
              verbose.MessagePos3(pos,t,s1,s2,s3);
              codegenerror:=olderrorcount<>Errorcount;
           end;
      end;


{****************************************************************************
                                 TProcInfo
****************************************************************************}

    constructor tprocinfo.init;
      begin
        parent:=nil;
        _class:=nil;
        procdef:=nil;
        framepointer_offset:=0;
        selfpointer_offset:=0;
        return_offset:=0;
        firsttemp_offset:=0;
        para_offset:=0;
        flags:=0;
        framepointer:=R_NO;
        globalsymbol:=false;
        exported:=false;
        no_fast_exit:=false;

        aktentrycode:=Taasmoutput.Create;
        aktexitcode:=Taasmoutput.Create;
        aktproccode:=Taasmoutput.Create;
        aktlocaldata:=Taasmoutput.Create;
      end;


    destructor tprocinfo.done;
      begin
         aktentrycode.free;
         aktexitcode.free;
         aktproccode.free;
         aktlocaldata.free;
      end;


{*****************************************************************************
         initialize/terminate the codegen for procedure and modules
*****************************************************************************}

    procedure codegen_newprocedure;
      begin
         aktbreaklabel:=nil;
         aktcontinuelabel:=nil;
         { aktexitlabel:=0; is store in oldaktexitlabel
           so it must not be reset to zero before this storage !}
         { new procinfo }
         new(procinfo,init);
{$ifdef fixLeaksOnError}
         procinfoStack.push(procinfo);
{$endif fixLeaksOnError}
      end;



    procedure codegen_doneprocedure;
      begin
{$ifdef fixLeaksOnError}
         if procinfo <> procinfoStack.pop then
           writeln('problem with procinfoStack!');
{$endif fixLeaksOnError}
         dispose(procinfo,done);
         procinfo:=nil;
      end;



    procedure codegen_newmodule;
      begin
         exprasmlist:=taasmoutput.create;
         datasegment:=taasmoutput.create;
         codesegment:=taasmoutput.create;
         bsssegment:=taasmoutput.create;
         debuglist:=taasmoutput.create;
         withdebuglist:=taasmoutput.create;
         consts:=taasmoutput.create;
         rttilist:=taasmoutput.create;
         ResourceStringList:=Nil;
         importssection:=nil;
         exportssection:=nil;
         resourcesection:=nil;
         { assembler symbols }
         asmsymbollist:=tdictionary.create;
         asmsymbollist.usehash;
         { resourcestrings }
         ResourceStrings:=TResourceStrings.Create;
      end;



    procedure codegen_donemodule;
{$ifdef MEMDEBUG}
      var
        d : tmemdebug;
{$endif}
      begin
{$ifdef MEMDEBUG}
         d:=tmemdebug.create('asmlist');
{$endif}
         exprasmlist.free;
         codesegment.free;
         bsssegment.free;
         datasegment.free;
         debuglist.free;
         withdebuglist.free;
         consts.free;
         rttilist.free;
         if assigned(ResourceStringList) then
          ResourceStringList.free;
         if assigned(importssection) then
          importssection.free;
         if assigned(exportssection) then
          exportssection.free;
         if assigned(resourcesection) then
          resourcesection.free;
{$ifdef MEMDEBUG}
         d.free;
{$endif}
         { assembler symbols }
{$ifdef MEMDEBUG}
         d:=tmemdebug.create('asmsymbol');
{$endif}
         asmsymbollist.free;
{$ifdef MEMDEBUG}
         d.free;
{$endif}
         { resource strings }
         ResourceStrings.free;
      end;


    function def_cgsize(def: tdef): tcgsize;
      begin
        case def.deftype of
          orddef,
          enumdef,
          setdef:
            begin
              result := int_cgsize(def.size);
              if is_signed(def) then
                result := tcgsize(ord(result)+(ord(OS_S8)-ord(OS_8)));
            end;
          classrefdef,
          pointerdef,
          procvardef:
            result := OS_ADDR;
          stringdef :
            begin
              if is_ansistring(def) or is_widestring(def) then
                result := OS_ADDR
              else
                result := OS_NO;
            end;
          objectdef :
            begin
              if is_class_or_interface(def) then
                result := OS_ADDR
              else
                result := OS_NO;
            end;
          floatdef:
            result := tfloat2tcgsize[tfloatdef(def).typ];
          recorddef :
            result:=int_cgsize(def.size);
          arraydef :
            begin
              if not is_special_array(def) then
                result := int_cgsize(def.size)
              else
                result := OS_NO;
            end;
          else
            begin
              { undefined size }
              result:=OS_NO;
            end;
        end;
      end;

    function int_cgsize(const l: aword): tcgsize;
      begin
        case l of
          1 :
            result := OS_8;
          2 :
            result := OS_16;
          3,4 :
            result := OS_32;
          5..8 :
            result := OS_64;
          else
            result:=OS_NO;
        end;
      end;


    function inverse_opcmp(opcmp: topcmp): topcmp;
      const
        list: array[TOpCmp] of TOpCmp =
          (OC_NONE,OC_NE,OC_LTE,OC_GTE,OC_LT,OC_GT,OC_EQ,OC_A,OC_AE,
           OC_B,OC_BE);
      begin
        inverse_opcmp := list[opcmp];
      end;


    function commutativeop(op: topcg): boolean;
      const
        list: array[topcg] of boolean =
          (true,true,true,false,false,true,true,false,false,
           true,false,false,false,false,true);
      begin
        commutativeop := list[op];
      end;


{$ifdef fixLeaksOnError}
procedure hcodegen_do_stop;
var p: pprocinfo;
begin
  p := pprocinfo(procinfoStack.pop);
  while p <> nil Do
    begin
      dispose(p,done);
      p := pprocinfo(procinfoStack.pop);
    end;
  procinfoStack.done;
  do_stop := hcodegen_old_do_stop;
  do_stop{$ifdef FPCPROCVAR}(){$endif};
end;

begin
  hcodegen_old_do_stop := do_stop;
  do_stop := {$ifdef FPCPROCVAR}@{$endif}hcodegen_do_stop;
  procinfoStack.init;
{$endif fixLeaksOnError}
end.
{
  $Log$
  Revision 1.19  2002-07-20 11:57:53  florian
    * types.pas renamed to defbase.pas because D6 contains a types
      unit so this would conflicts if D6 programms are compiled
    + Willamette/SSE2 instructions to assembler added

  Revision 1.18  2002/07/01 18:46:22  peter
    * internal linker
    * reorganized aasm layer

  Revision 1.17  2002/05/20 13:30:40  carl
  * bugfix of hdisponen (base must be set, not index)
  * more portability fixes

  Revision 1.16  2002/05/18 13:34:05  peter
    * readded missing revisions

  Revision 1.15  2002/05/16 19:46:35  carl
  + defines.inc -> fpcdefs.inc to avoid conflicts if compiling by hand
  + try to fix temp allocation (still in ifdef)
  + generic constructor calls
  + start of tassembler / tmodulebase class cleanup

  Revision 1.13  2002/04/25 20:16:38  peter
    * moved more routines from cga/n386util

  Revision 1.12  2002/04/21 15:28:06  carl
  - remove duplicate constants
  - move some constants to cginfo

  Revision 1.11  2002/04/20 21:32:23  carl
  + generic FPC_CHECKPOINTER
  + first parameter offset in stack now portable
  * rename some constants
  + move some cpu stuff to other units
  - remove unused constents
  * fix stacksize for some targets
  * fix generic size problems which depend now on EXTEND_SIZE constant

  Revision 1.10  2002/04/07 09:13:39  carl
  + documentation
  - remove unused variables

  Revision 1.9  2002/04/04 19:05:54  peter
    * removed unused units
    * use tlocation.size in cg.a_*loc*() routines

  Revision 1.8  2002/04/02 17:11:27  peter
    * tlocation,treference update
    * LOC_CONSTANT added for better constant handling
    * secondadd splitted in multiple routines
    * location_force_reg added for loading a location to a register
      of a specified size
    * secondassignment parses now first the right and then the left node
      (this is compatible with Kylix). This saves a lot of push/pop especially
      with string operations
    * adapted some routines to use the new cg methods

  Revision 1.7  2002/03/31 20:26:33  jonas
    + a_loadfpu_* and a_loadmm_* methods in tcg
    * register allocation is now handled by a class and is mostly processor
      independent (+rgobj.pas and i386/rgcpu.pas)
    * temp allocation is now handled by a class (+tgobj.pas, -i386\tgcpu.pas)
    * some small improvements and fixes to the optimizer
    * some register allocation fixes
    * some fpuvaroffset fixes in the unary minus node
    * push/popusedregisters is now called rg.save/restoreusedregisters and
      (for i386) uses temps instead of push/pop's when using -Op3 (that code is
      also better optimizable)
    * fixed and optimized register saving/restoring for new/dispose nodes
    * LOC_FPU locations now also require their "register" field to be set to
      R_ST, not R_ST0 (the latter is used for LOC_CFPUREGISTER locations only)
    - list field removed of the tnode class because it's not used currently
      and can cause hard-to-find bugs

  Revision 1.6  2002/03/04 19:10:11  peter
    * removed compiler warnings

}