{
    Copyright (C) 2019 Dmitry Boyarintsev

    This unit handles the temporary variables for the WebAssembly

    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 tgcpu;

{$i fpcdefs.inc}

  interface

    uses
       globtype,
       aasmdata,
       cgutils,
       symtype,tgobj;

    type

       { ttgwasm }

       ttgwasm = class(ttgobj)
        //protected
        // procedure getimplicitobjtemp(list: TAsmList; def: tdef; temptype: ttemptype; out ref: treference);
        // function getifspecialtemp(list: TAsmList; def: tdef; forcesize: asizeint; temptype: ttemptype; out ref: treference): boolean;
         procedure alloctemp(list: TAsmList; size: asizeint; alignment: shortint; temptype: ttemptype; def: tdef; fini: boolean; out ref: treference); override;
        public
         constructor create; override;
         procedure setfirsttemp(l : asizeint); override;
         //procedure getlocal(list: TAsmList; size: asizeint; alignment: shortint; def: tdef; var ref: treference); override;
         //procedure gethltemp(list: TAsmList; def: tdef; forcesize: asizeint; temptype: ttemptype; out ref: treference); override;
         //procedure gethltempmanaged(list: TAsmList; def: tdef; temptype: ttemptype; out ref: treference); override;
       end;

  implementation

    uses
       verbose,
       cgbase,
       symconst,symtable,symdef,symsym,symcpu,defutil,
       cpubase,aasmbase,aasmcpu,
       hlcgobj,hlcgcpu;


    { ttgwasm }

    //procedure ttgwasm.getimplicitobjtemp(list: TAsmList; def: tdef; temptype: ttemptype; out ref: treference);
    //  var
    //    sym: tsym;
    //    pd: tprocdef;
    //  begin
    //    gettemp(list,java_jlobject.size,java_jlobject.alignment,temptype,ref);
    //    list.concat(taicpu.op_sym(a_new,current_asmdata.RefAsmSymbol(tabstractrecorddef(def).jvm_full_typename(true),AT_METADATA)));
    //    { the constructor doesn't return anything, so put a duplicate of the
    //      self pointer on the evaluation stack for use as function result
    //      after the constructor has run }
    //    list.concat(taicpu.op_none(a_dup));
    //    thlcgjvm(hlcg).incstack(list,2);
    //    { call the constructor }
    //    sym:=tsym(tabstractrecorddef(def).symtable.find('CREATE'));
    //    if assigned(sym) and
    //       (sym.typ=procsym) then
    //      begin
    //        pd:=tprocsym(sym).find_bytype_parameterless(potype_constructor);
    //        if not assigned(pd) then
    //          internalerror(2011032701);
    //      end
    //    else
    //      internalerror(2011060301);
    //    hlcg.a_call_name(list,pd,pd.mangledname,[],nil,false);
    //    thlcgjvm(hlcg).decstack(list,1);
    //    { store reference to instance }
    //    thlcgjvm(hlcg).a_load_stack_ref(list,java_jlobject,ref,0);
    //  end;


    //function ttgwasm.getifspecialtemp(list: TAsmList; def: tdef; forcesize: asizeint; temptype: ttemptype; out ref: treference): boolean;
    //  var
    //    eledef: tdef;
    //    ndim: longint;
    //    sym: tsym;
    //    pd: tprocdef;
    //  begin
    //    result:=false;
    //    case def.typ of
    //      arraydef:
    //        begin
    //          if not is_dynamic_array(def) then
    //            begin
    //              { allocate an array of the right size }
    //              gettemp(list,java_jlobject.size,java_jlobject.alignment,temptype,ref);
    //              ndim:=0;
    //              eledef:=def;
    //              repeat
    //                if forcesize<>-1 then
    //                  thlcgjvm(hlcg).a_load_const_stack(list,s32inttype,forcesize div tarraydef(eledef).elesize,R_INTREGISTER)
    //                else
    //                  thlcgjvm(hlcg).a_load_const_stack(list,s32inttype,tarraydef(eledef).elecount,R_INTREGISTER);
    //                eledef:=tarraydef(eledef).elementdef;
    //                inc(ndim);
    //                forcesize:=-1;
    //              until (eledef.typ<>arraydef) or
    //                    is_dynamic_array(eledef);
    //              eledef:=tarraydef(def).elementdef;
    //              thlcgjvm(hlcg).g_newarray(list,def,ndim);
    //              thlcgjvm(hlcg).a_load_stack_ref(list,java_jlobject,ref,0);
    //              result:=true;
    //            end;
    //        end;
    //      recorddef:
    //        begin
    //          getimplicitobjtemp(list,def,temptype,ref);
    //          result:=true;
    //        end;
    //      setdef:
    //        begin
    //          if tsetdef(def).elementdef.typ=enumdef then
    //            begin
    //              { load enum class type }
    //              list.concat(taicpu.op_sym(a_ldc,current_asmdata.RefAsmSymbol(tcpuenumdef(tenumdef(tsetdef(def).elementdef).getbasedef).classdef.jvm_full_typename(true),AT_METADATA)));
    //              thlcgjvm(hlcg).incstack(current_asmdata.CurrAsmList,1);
    //              { call tenumset.noneOf() class method }
    //              sym:=tsym(tobjectdef(java_juenumset).symtable.find('NONEOF'));
    //              if assigned(sym) and
    //                 (sym.typ=procsym) then
    //                begin
    //                  if tprocsym(sym).procdeflist.Count<>1 then
    //                    internalerror(2011062801);
    //                  pd:=tprocdef(tprocsym(sym).procdeflist[0]);
    //                  hlcg.a_call_name(list,pd,pd.mangledname,[],nil,false);
    //                end;
    //              { static calls method replaces parameter with set instance
    //                -> no change in stack height }
    //            end
    //          else
    //            begin
    //              list.concat(taicpu.op_sym(a_new,current_asmdata.RefAsmSymbol(java_jubitset.jvm_full_typename(true),AT_METADATA)));
    //              { the constructor doesn't return anything, so put a duplicate of the
    //                self pointer on the evaluation stack for use as function result
    //                after the constructor has run }
    //              list.concat(taicpu.op_none(a_dup));
    //              thlcgjvm(hlcg).incstack(list,2);
    //              { call the constructor }
    //              sym:=tsym(java_jubitset.symtable.find('CREATE'));
    //              if assigned(sym) and
    //                 (sym.typ=procsym) then
    //                begin
    //                  pd:=tprocsym(sym).find_bytype_parameterless(potype_constructor);
    //                  if not assigned(pd) then
    //                    internalerror(2011062802);
    //                end
    //              else
    //                internalerror(2011062803);
    //              hlcg.a_call_name(list,pd,pd.mangledname,[],nil,false);
    //              { duplicate self pointer is removed }
    //              thlcgjvm(hlcg).decstack(list,1);
    //            end;
    //          { store reference to instance }
    //          gettemp(list,java_jlobject.size,java_jlobject.alignment,temptype,ref);
    //          thlcgjvm(hlcg).a_load_stack_ref(list,java_jlobject,ref,0);
    //          result:=true;
    //        end;
    //      procvardef:
    //        begin
    //          if not tprocvardef(def).is_addressonly then
    //            begin
    //              getimplicitobjtemp(list,tcpuprocvardef(def).classdef,temptype,ref);
    //              result:=true;
    //            end;
    //        end;
    //      stringdef:
    //        begin
    //          if is_shortstring(def) then
    //            begin
    //              gettemp(list,java_jlobject.size,java_jlobject.alignment,temptype,ref);
    //              { add the maxlen parameter (s8inttype because parameters must
    //                be sign extended) }
    //              thlcgjvm(hlcg).a_load_const_stack(list,s8inttype,shortint(tstringdef(def).len),R_INTREGISTER);
    //              { call the constructor }
    //              sym:=tsym(tobjectdef(java_shortstring).symtable.find('CREATEEMPTY'));
    //              if assigned(sym) and
    //                 (sym.typ=procsym) then
    //                begin
    //                  if tprocsym(sym).procdeflist.Count<>1 then
    //                    internalerror(2011052404);
    //                  pd:=tprocdef(tprocsym(sym).procdeflist[0]);
    //                  hlcg.a_call_name(list,pd,pd.mangledname,[],nil,false);
    //                end;
    //              { static calls method replaces parameter with string instance
    //                -> no change in stack height }
    //              { store reference to instance }
    //              thlcgjvm(hlcg).a_load_stack_ref(list,java_jlobject,ref,0);
    //              result:=true;
    //            end;
    //        end;
    //      filedef:
    //        begin
    //          case tfiledef(def).filetyp of
    //            ft_text:
    //              result:=getifspecialtemp(list,search_system_type('TEXTREC').typedef,forcesize,temptype,ref);
    //            ft_typed,
    //            ft_untyped:
    //              result:=getifspecialtemp(list,search_system_type('FILEREC').typedef,forcesize,temptype,ref);
    //          end;
    //        end;
    //      else
    //        ;
    //    end;
    //  end;


    procedure ttgwasm.alloctemp(list: TAsmList; size: asizeint; alignment: shortint; temptype: ttemptype; def: tdef; fini: boolean; out ref: treference);
      begin
        { the WebAssembly only supports 1 slot (= 4 bytes in FPC) and 2 slot (= 8 bytes in
          FPC) temps on the stack. double and int64 are 2 slots, the rest is one slot.
          There are no problems with reusing the same slot for a value of a different
          type. There are no alignment requirements either. }
        if size<4 then
          size:=4;
        if not(size in [4,8]) then
          internalerror(2010121401);
        { don't pass on "def", since we don't care if a slot is used again for a
          different type }
        inherited alloctemp(list, size shr 2, 1, temptype, nil, false, ref);
      end;

    constructor ttgwasm.create;
      begin
        inherited create;
        direction := 1; // temp variables are allocated as "locals", and it starts with 0 and goes beyond!
      end;


    procedure ttgwasm.setfirsttemp(l: asizeint);
      begin
        firsttemp:=l;
        lasttemp:=l;
      end;


    //procedure ttgwasm.getlocal(list: TAsmList; size: asizeint; alignment: shortint; def: tdef; var ref: treference);
    //  begin
    //    if not getifspecialtemp(list,def,size,tt_persistent,ref) then
    //      inherited;
    //  end;


    //procedure ttgjvm.gethltemp(list: TAsmList; def: tdef; forcesize: asizeint; temptype: ttemptype; out ref: treference);
    //  begin
    //    if not getifspecialtemp(list,def,forcesize,temptype,ref) then
    //      inherited;
    //  end;
    //
    //procedure ttgjvm.gethltempmanaged(list: TAsmList; def: tdef; temptype: ttemptype; out ref: treference);
    //  begin
    //    gethltemp(list,def,def.size,temptype,ref);
    //  end;


initialization
  tgobjclass:=ttgwasm;
end.