fpc/compiler/arm/cgcpu.pas

{

    Copyright (c) 2003 by Florian Klaempfl
    Member of the Free Pascal development team

    This unit implements the code generator for the ARM

    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 cgcpu;

{$i fpcdefs.inc}

  interface

    uses
       globtype,symtype,symdef,
       cgbase,cgutils,cgobj,
       aasmbase,aasmcpu,aasmtai,aasmdata,
       parabase,
       cpubase,cpuinfo,node,cg64f32,rgcpu;


    type
      tcgarm = class(tcg)
        { true, if the next arithmetic operation should modify the flags }
        cgsetflags : boolean;
        procedure init_register_allocators;override;
        procedure done_register_allocators;override;

        procedure a_param_const(list : TAsmList;size : tcgsize;a : aint;const paraloc : TCGPara);override;
        procedure a_param_ref(list : TAsmList;size : tcgsize;const r : treference;const paraloc : TCGPara);override;
        procedure a_paramaddr_ref(list : TAsmList;const r : treference;const paraloc : TCGPara);override;

        procedure a_call_name(list : TAsmList;const s : string);override;
        procedure a_call_reg(list : TAsmList;reg: tregister);override;
        procedure a_call_ref(list : TAsmList;ref: treference);override;

        procedure a_op_const_reg(list : TAsmList; Op: TOpCG; size: TCGSize; a: aint; reg: TRegister); override;
        procedure a_op_reg_reg(list : TAsmList; Op: TOpCG; size: TCGSize; src, dst: TRegister); override;

        procedure a_op_const_reg_reg(list: TAsmList; op: TOpCg;
          size: tcgsize; a: aint; src, dst: tregister); override;
        procedure a_op_reg_reg_reg(list: TAsmList; op: TOpCg;
          size: tcgsize; src1, src2, dst: tregister); override;
        procedure a_op_const_reg_reg_checkoverflow(list: TAsmList; op: TOpCg; size: tcgsize; a: aint; src, dst: tregister;setflags : boolean;var ovloc : tlocation);override;
        procedure a_op_reg_reg_reg_checkoverflow(list: TAsmList; op: TOpCg; size: tcgsize; src1, src2, dst: tregister;setflags : boolean;var ovloc : tlocation);override;

        { move instructions }
        procedure a_load_const_reg(list : TAsmList; size: tcgsize; a : aint;reg : tregister);override;
        procedure a_load_reg_ref(list : TAsmList; fromsize, tosize: tcgsize; reg : tregister;const ref : treference);override;
        procedure a_load_ref_reg(list : TAsmList; fromsize, tosize : tcgsize;const Ref : treference;reg : tregister);override;
        procedure a_load_reg_reg(list : TAsmList; fromsize, tosize : tcgsize;reg1,reg2 : tregister);override;
        function a_internal_load_reg_ref(list : TAsmList; fromsize, tosize: tcgsize; reg : tregister;const ref : treference):treference;
        function a_internal_load_ref_reg(list : TAsmList; fromsize, tosize : tcgsize;const Ref : treference;reg : tregister):treference;

        { fpu move instructions }
        procedure a_loadfpu_reg_reg(list: TAsmList; fromsize, tosize: tcgsize; reg1, reg2: tregister); override;
        procedure a_loadfpu_ref_reg(list: TAsmList; fromsize, tosize: tcgsize; const ref: treference; reg: tregister); override;
        procedure a_loadfpu_reg_ref(list: TAsmList; fromsize, tosize: tcgsize; reg: tregister; const ref: treference); override;

        procedure a_paramfpu_ref(list : TAsmList;size : tcgsize;const ref : treference;const paraloc : TCGPara);override;
        {  comparison operations }
        procedure a_cmp_const_reg_label(list : TAsmList;size : tcgsize;cmp_op : topcmp;a : aint;reg : tregister;
          l : tasmlabel);override;
        procedure a_cmp_reg_reg_label(list : TAsmList;size : tcgsize;cmp_op : topcmp;reg1,reg2 : tregister;l : tasmlabel); override;

        procedure a_jmp_name(list : TAsmList;const s : string); override;
        procedure a_jmp_always(list : TAsmList;l: tasmlabel); override;
        procedure a_jmp_flags(list : TAsmList;const f : TResFlags;l: tasmlabel); override;

        procedure g_flags2reg(list: TAsmList; size: TCgSize; const f: TResFlags; reg: TRegister); override;

        procedure g_proc_entry(list : TAsmList;localsize : longint;nostackframe:boolean);override;
        procedure g_proc_exit(list : TAsmList;parasize : longint;nostackframe:boolean); override;

        procedure a_loadaddr_ref_reg(list : TAsmList;const ref : treference;r : tregister);override;

        procedure g_concatcopy(list : TAsmList;const source,dest : treference;len : aint);override;
        procedure g_concatcopy_unaligned(list : TAsmList;const source,dest : treference;len : aint);override;
        procedure g_concatcopy_move(list : TAsmList;const source,dest : treference;len : aint);
        procedure g_concatcopy_internal(list : TAsmList;const source,dest : treference;len : aint;aligned : boolean);

        procedure g_overflowcheck(list: TAsmList; const l: tlocation; def: tdef); override;
        procedure g_overflowCheck_loc(List:TAsmList;const Loc:TLocation;def:TDef;ovloc : tlocation);override;

        procedure g_save_registers(list : TAsmList);override;
        procedure g_restore_registers(list : TAsmList);override;

        procedure a_jmp_cond(list : TAsmList;cond : TOpCmp;l: tasmlabel);
        procedure fixref(list : TAsmList;var ref : treference);
        function handle_load_store(list:TAsmList;op: tasmop;oppostfix : toppostfix;reg:tregister;ref: treference):treference;

        procedure g_intf_wrapper(list: TAsmList; procdef: tprocdef; const labelname: string; ioffset: longint);override;
        procedure g_adjust_self_value(list:TAsmList;procdef: tprocdef;ioffset: aint); override;
        procedure g_stackpointer_alloc(list : TAsmList;size : longint);override;
      private
        { clear out potential overflow bits from 8 or 16 bit operations  }
        { the upper 24/16 bits of a register after an operation          }
        procedure maybeadjustresult(list: TAsmList; op: TOpCg; size: tcgsize; dst: tregister);
      end;

      tcg64farm = class(tcg64f32)
        procedure a_op64_reg_reg(list : TAsmList;op:TOpCG;size : tcgsize;regsrc,regdst : tregister64);override;
        procedure a_op64_const_reg(list : TAsmList;op:TOpCG;size : tcgsize;value : int64;reg : tregister64);override;
        procedure a_op64_const_reg_reg(list: TAsmList;op:TOpCG;size : tcgsize;value : int64;regsrc,regdst : tregister64);override;
        procedure a_op64_reg_reg_reg(list: TAsmList;op:TOpCG;size : tcgsize;regsrc1,regsrc2,regdst : tregister64);override;
        procedure a_op64_const_reg_reg_checkoverflow(list: TAsmList;op:TOpCG;size : tcgsize;value : int64;regsrc,regdst : tregister64;setflags : boolean;var ovloc : tlocation);override;
        procedure a_op64_reg_reg_reg_checkoverflow(list: TAsmList;op:TOpCG;size : tcgsize;regsrc1,regsrc2,regdst : tregister64;setflags : boolean;var ovloc : tlocation);override;
      end;

    const
      OpCmp2AsmCond : Array[topcmp] of TAsmCond = (C_NONE,C_EQ,C_GT,
                           C_LT,C_GE,C_LE,C_NE,C_LS,C_CC,C_CS,C_HI);

      winstackpagesize = 4096;

    function get_fpu_postfix(def : tdef) : toppostfix;

  implementation


    uses
       globals,verbose,systems,cutils,
       fmodule,
       symconst,symsym,
       tgobj,
       procinfo,cpupi,
       paramgr;


    function get_fpu_postfix(def : tdef) : toppostfix;
      begin
        if def.typ=floatdef then
          begin
            case tfloatdef(def).floattype of
              s32real:
                result:=PF_S;
              s64real:
                result:=PF_D;
              s80real:
                result:=PF_E;
              else
                internalerror(200401272);
            end;
          end
        else
          internalerror(200401271);
      end;


    procedure tcgarm.init_register_allocators;
      begin
        inherited init_register_allocators;
        { currently, we save R14 always, so we can use it }
        rg[R_INTREGISTER]:=trgintcpu.create(R_INTREGISTER,R_SUBWHOLE,
            [RS_R0,RS_R1,RS_R2,RS_R3,RS_R4,RS_R5,RS_R6,RS_R7,RS_R8,
             RS_R9,RS_R10,RS_R12,RS_R14],first_int_imreg,[]);
        rg[R_FPUREGISTER]:=trgcpu.create(R_FPUREGISTER,R_SUBNONE,
            [RS_F0,RS_F1,RS_F2,RS_F3,RS_F4,RS_F5,RS_F6,RS_F7],first_fpu_imreg,[]);
        rg[R_MMREGISTER]:=trgcpu.create(R_MMREGISTER,R_SUBNONE,
            [RS_S0,RS_S1,RS_R2,RS_R3,RS_R4,RS_S31],first_mm_imreg,[]);
      end;


    procedure tcgarm.done_register_allocators;
      begin
        rg[R_INTREGISTER].free;
        rg[R_FPUREGISTER].free;
        rg[R_MMREGISTER].free;
        inherited done_register_allocators;
      end;


    procedure tcgarm.a_param_const(list : TAsmList;size : tcgsize;a : aint;const paraloc : TCGPara);
      var
        ref: treference;
      begin
        paraloc.check_simple_location;
        case paraloc.location^.loc of
          LOC_REGISTER,LOC_CREGISTER:
            a_load_const_reg(list,size,a,paraloc.location^.register);
          LOC_REFERENCE:
            begin
               reference_reset(ref);
               ref.base:=paraloc.location^.reference.index;
               ref.offset:=paraloc.location^.reference.offset;
               a_load_const_ref(list,size,a,ref);
            end;
          else
            internalerror(2002081101);
        end;
      end;


    procedure tcgarm.a_param_ref(list : TAsmList;size : tcgsize;const r : treference;const paraloc : TCGPara);
      var
        tmpref, ref: treference;
        location: pcgparalocation;
        sizeleft: aint;
      begin
        location := paraloc.location;
        tmpref := r;
        sizeleft := paraloc.intsize;
        while assigned(location) do
          begin
            case location^.loc of
              LOC_REGISTER,LOC_CREGISTER:
                a_load_ref_reg(list,location^.size,location^.size,tmpref,location^.register);
              LOC_REFERENCE:
                begin
                  reference_reset_base(ref,location^.reference.index,location^.reference.offset);
                  { doubles in softemu mode have a strange order of registers and references }
                  if location^.size=OS_32 then
                    g_concatcopy(list,tmpref,ref,4)
                  else
                    begin
                      g_concatcopy(list,tmpref,ref,sizeleft);
                      if assigned(location^.next) then
                        internalerror(2005010710);
                    end;
                end;
              LOC_FPUREGISTER,LOC_CFPUREGISTER:
                case location^.size of
                   OS_F32, OS_F64:
                     a_loadfpu_ref_reg(list,location^.size,location^.size,tmpref,location^.register);
                   else
                     internalerror(2002072801);
                end;
              LOC_VOID:
                begin
                  // nothing to do
                end;
              else
                internalerror(2002081103);
            end;
            inc(tmpref.offset,tcgsize2size[location^.size]);
            dec(sizeleft,tcgsize2size[location^.size]);
            location := location^.next;
          end;
      end;


    procedure tcgarm.a_paramaddr_ref(list : TAsmList;const r : treference;const paraloc : TCGPara);
      var
        ref: treference;
        tmpreg: tregister;
      begin
        paraloc.check_simple_location;
        case paraloc.location^.loc of
          LOC_REGISTER,LOC_CREGISTER:
            a_loadaddr_ref_reg(list,r,paraloc.location^.register);
          LOC_REFERENCE:
            begin
              reference_reset(ref);
              ref.base := paraloc.location^.reference.index;
              ref.offset := paraloc.location^.reference.offset;
              tmpreg := getintregister(list,OS_ADDR);
              a_loadaddr_ref_reg(list,r,tmpreg);
              a_load_reg_ref(list,OS_ADDR,OS_ADDR,tmpreg,ref);
            end;
          else
            internalerror(2002080701);
        end;
      end;


    procedure tcgarm.a_call_name(list : TAsmList;const s : string);
      begin
        list.concat(taicpu.op_sym(A_BL,current_asmdata.RefAsmSymbol(s)));
{
        the compiler does not properly set this flag anymore in pass 1, and
        for now we only need it after pass 2 (I hope) (JM)
          if not(pi_do_call in current_procinfo.flags) then
            internalerror(2003060703);
}
        include(current_procinfo.flags,pi_do_call);
      end;


    procedure tcgarm.a_call_reg(list : TAsmList;reg: tregister);
      begin
        list.concat(taicpu.op_reg_reg(A_MOV,NR_R14,NR_PC));
        list.concat(taicpu.op_reg_reg(A_MOV,NR_PC,reg));
{
        the compiler does not properly set this flag anymore in pass 1, and
        for now we only need it after pass 2 (I hope) (JM)
          if not(pi_do_call in current_procinfo.flags) then
            internalerror(2003060703);
}
        include(current_procinfo.flags,pi_do_call);
      end;


    procedure tcgarm.a_call_ref(list : TAsmList;ref: treference);
      begin
        a_reg_alloc(list,NR_R12);
        a_load_ref_reg(list,OS_ADDR,OS_ADDR,ref,NR_R12);
        list.concat(taicpu.op_reg_reg(A_MOV,NR_R14,NR_PC));
        list.concat(taicpu.op_reg_reg(A_MOV,NR_PC,NR_R12));
        a_reg_dealloc(list,NR_R12);
        include(current_procinfo.flags,pi_do_call);
      end;


     procedure tcgarm.a_op_const_reg(list : TAsmList; Op: TOpCG; size: TCGSize; a: aint; reg: TRegister);
       begin
          a_op_const_reg_reg(list,op,size,a,reg,reg);
       end;


     procedure tcgarm.a_op_reg_reg(list : TAsmList; Op: TOpCG; size: TCGSize; src, dst: TRegister);
       begin
         case op of
           OP_NEG:
             list.concat(taicpu.op_reg_reg_const(A_RSB,dst,src,0));
           OP_NOT:
             begin
               list.concat(taicpu.op_reg_reg(A_MVN,dst,src));
               case size of
                 OS_8 :
                   a_op_const_reg_reg(list,OP_AND,OS_INT,$ff,dst,dst);
                 OS_16 :
                   a_op_const_reg_reg(list,OP_AND,OS_INT,$ffff,dst,dst);
               end;
             end
           else
             a_op_reg_reg_reg(list,op,OS_32,src,dst,dst);
         end;
       end;


    const
      op_reg_reg_opcg2asmop: array[TOpCG] of tasmop =
        (A_NONE,A_MOV,A_ADD,A_AND,A_NONE,A_NONE,A_MUL,A_MUL,A_NONE,A_NONE,A_ORR,
         A_NONE,A_NONE,A_NONE,A_SUB,A_EOR,A_NONE,A_NONE);


    procedure tcgarm.a_op_const_reg_reg(list: TAsmList; op: TOpCg;
      size: tcgsize; a: aint; src, dst: tregister);
      var
        ovloc : tlocation;
      begin
        a_op_const_reg_reg_checkoverflow(list,op,size,a,src,dst,false,ovloc);
      end;


    procedure tcgarm.a_op_reg_reg_reg(list: TAsmList; op: TOpCg;
      size: tcgsize; src1, src2, dst: tregister);
      var
        ovloc : tlocation;
      begin
        a_op_reg_reg_reg_checkoverflow(list,op,size,src1,src2,dst,false,ovloc);
      end;


    procedure tcgarm.a_op_const_reg_reg_checkoverflow(list: TAsmList; op: TOpCg; size: tcgsize; a: aint; src, dst: tregister;setflags : boolean;var ovloc : tlocation);
      var
        shift : byte;
        tmpreg : tregister;
        so : tshifterop;
        l1 : longint;
      begin
        ovloc.loc:=LOC_VOID;
        if is_shifter_const(-a,shift) then
          case op of
            OP_ADD:
              begin
                op:=OP_SUB;
                a:=aint(dword(-a));
              end;
            OP_SUB:
              begin
                op:=OP_ADD;
                a:=aint(dword(-a));
              end
          end;

        if is_shifter_const(a,shift) and not(op in [OP_IMUL,OP_MUL]) then
          case op of
            OP_NEG,OP_NOT,
            OP_DIV,OP_IDIV:
              internalerror(200308281);
            OP_SHL:
              begin
                if a>32 then
                  internalerror(200308294);
                if a<>0 then
                  begin
                    shifterop_reset(so);
                    so.shiftmode:=SM_LSL;
                    so.shiftimm:=a;
                    list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src,so));
                  end
                else
                 list.concat(taicpu.op_reg_reg(A_MOV,dst,src));
              end;
            OP_ROL:
              begin
                if a>32 then
                  internalerror(200308294);
                if a<>0 then
                  begin
                    shifterop_reset(so);
                    so.shiftmode:=SM_ROR;
                    so.shiftimm:=32-a;
                    list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src,so));
                  end
                else
                 list.concat(taicpu.op_reg_reg(A_MOV,dst,src));
              end;
            OP_ROR:
              begin
                if a>32 then
                  internalerror(200308294);
                if a<>0 then
                  begin
                    shifterop_reset(so);
                    so.shiftmode:=SM_ROR;
                    so.shiftimm:=a;
                    list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src,so));
                  end
                else
                 list.concat(taicpu.op_reg_reg(A_MOV,dst,src));
              end;
            OP_SHR:
              begin
                if a>32 then
                  internalerror(200308292);
                shifterop_reset(so);
                if a<>0 then
                  begin
                    so.shiftmode:=SM_LSR;
                    so.shiftimm:=a;
                    list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src,so));
                  end
                else
                 list.concat(taicpu.op_reg_reg(A_MOV,dst,src));
              end;
            OP_SAR:
              begin
                if a>32 then
                  internalerror(200308295);
                if a<>0 then
                  begin
                    shifterop_reset(so);
                    so.shiftmode:=SM_ASR;
                    so.shiftimm:=a;
                    list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src,so));
                  end
                else
                 list.concat(taicpu.op_reg_reg(A_MOV,dst,src));
              end;
            else
              list.concat(setoppostfix(
                  taicpu.op_reg_reg_const(op_reg_reg_opcg2asmop[op],dst,src,a),toppostfix(ord(cgsetflags or setflags)*ord(PF_S))
              ));
              if (cgsetflags or setflags) and (size in [OS_8,OS_16,OS_32]) then
                begin
                  ovloc.loc:=LOC_FLAGS;
                  case op of
                    OP_ADD:
                      ovloc.resflags:=F_CS;
                    OP_SUB:
                      ovloc.resflags:=F_CC;
                  end;
                end;
          end
        else
          begin
            { there could be added some more sophisticated optimizations }
            if (op in [OP_MUL,OP_IMUL]) and (a=1) then
              a_load_reg_reg(list,size,size,src,dst)
            else if (op in [OP_MUL,OP_IMUL]) and (a=0) then
              a_load_const_reg(list,size,0,dst)
            else if (op in [OP_IMUL]) and (a=-1) then
              a_op_reg_reg(list,OP_NEG,size,src,dst)
            { we do this here instead in the peephole optimizer because
              it saves us a register }
            else if (op in [OP_MUL,OP_IMUL]) and ispowerof2(a,l1) and not(cgsetflags or setflags) then
              a_op_const_reg_reg(list,OP_SHL,size,l1,src,dst)
            { for example : b=a*5 -> b=a*4+a with add instruction and shl }
            else if (op in [OP_MUL,OP_IMUL]) and ispowerof2(a-1,l1) and not(cgsetflags or setflags) then
              begin
                if l1>32 then{roozbeh does this ever happen?}
                  internalerror(200308296);
                shifterop_reset(so);
                so.shiftmode:=SM_LSL;
                so.shiftimm:=l1;
                list.concat(taicpu.op_reg_reg_reg_shifterop(A_ADD,dst,src,src,so));
              end
            else
              begin
                tmpreg:=getintregister(list,size);
                a_load_const_reg(list,size,a,tmpreg);
                a_op_reg_reg_reg_checkoverflow(list,op,size,tmpreg,src,dst,setflags,ovloc);
              end;
          end;
        maybeadjustresult(list,op,size,dst);
      end;


    procedure tcgarm.a_op_reg_reg_reg_checkoverflow(list: TAsmList; op: TOpCg; size: tcgsize; src1, src2, dst: tregister;setflags : boolean;var ovloc : tlocation);
      var
        so : tshifterop;
        tmpreg,overflowreg : tregister;
        asmop : tasmop;
      begin
        ovloc.loc:=LOC_VOID;
        case op of
          OP_NEG,OP_NOT,
          OP_DIV,OP_IDIV:
            internalerror(200308281);
          OP_SHL:
            begin
              shifterop_reset(so);
              so.rs:=src1;
              so.shiftmode:=SM_LSL;
              list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src2,so));
            end;
          OP_SHR:
            begin
              shifterop_reset(so);
              so.rs:=src1;
              so.shiftmode:=SM_LSR;
              list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src2,so));
            end;
          OP_SAR:
            begin
              shifterop_reset(so);
              so.rs:=src1;
              so.shiftmode:=SM_ASR;
              list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src2,so));
            end;
          OP_ROL:
            begin
              if not(size in [OS_32,OS_S32]) then
                internalerror(2008072801);
              { simulate ROL by ror'ing 32-value }
              tmpreg:=getintregister(list,OS_32);
              list.concat(taicpu.op_reg_const(A_MOV,tmpreg,32));
              list.concat(taicpu.op_reg_reg_reg(A_SUB,src1,tmpreg,src1));
              shifterop_reset(so);
              so.rs:=src1;
              so.shiftmode:=SM_ROR;
              list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src2,so));
            end;
          OP_ROR:
            begin
              if not(size in [OS_32,OS_S32]) then
                internalerror(2008072802);
              shifterop_reset(so);
              so.rs:=src1;
              so.shiftmode:=SM_ROR;
              list.concat(taicpu.op_reg_reg_shifterop(A_MOV,dst,src2,so));
            end;
          OP_IMUL,
          OP_MUL:
            begin
              if cgsetflags or setflags then
                begin
                  overflowreg:=getintregister(list,size);
                  if op=OP_IMUL then
                    asmop:=A_SMULL
                  else
                    asmop:=A_UMULL;
                  { the arm doesn't allow that rd and rm are the same }
                  if dst=src2 then
                    begin
                      if dst<>src1 then
                        list.concat(taicpu.op_reg_reg_reg_reg(asmop,dst,overflowreg,src1,src2))
                      else
                        begin
                          tmpreg:=getintregister(list,size);
                          a_load_reg_reg(list,size,size,src2,dst);
                          list.concat(taicpu.op_reg_reg_reg_reg(asmop,dst,overflowreg,tmpreg,src1));
                        end;
                    end
                  else
                    list.concat(taicpu.op_reg_reg_reg_reg(asmop,dst,overflowreg,src2,src1));
                  if op=OP_IMUL then
                    begin
                      shifterop_reset(so);
                      so.shiftmode:=SM_ASR;
                      so.shiftimm:=31;
                      list.concat(taicpu.op_reg_reg_shifterop(A_CMP,overflowreg,dst,so));
                    end
                  else
                    list.concat(taicpu.op_reg_const(A_CMP,overflowreg,0));

                   ovloc.loc:=LOC_FLAGS;
                   ovloc.resflags:=F_NE;
                end
              else
                begin
                  { the arm doesn't allow that rd and rm are the same }
                  if dst=src2 then
                    begin
                      if dst<>src1 then
                        list.concat(taicpu.op_reg_reg_reg(A_MUL,dst,src1,src2))
                      else
                        begin
                          tmpreg:=getintregister(list,size);
                          a_load_reg_reg(list,size,size,src2,dst);
                          list.concat(taicpu.op_reg_reg_reg(A_MUL,dst,tmpreg,src1));
                        end;
                    end
                  else
                    list.concat(taicpu.op_reg_reg_reg(A_MUL,dst,src2,src1));
                end;
            end;
          else
            list.concat(setoppostfix(
                taicpu.op_reg_reg_reg(op_reg_reg_opcg2asmop[op],dst,src2,src1),toppostfix(ord(cgsetflags or setflags)*ord(PF_S))
              ));
        end;
        maybeadjustresult(list,op,size,dst);
      end;


     procedure tcgarm.a_load_const_reg(list : TAsmList; size: tcgsize; a : aint;reg : tregister);
       var
          imm_shift : byte;
          l : tasmlabel;
          hr : treference;
       begin
          if not(size in [OS_8,OS_S8,OS_16,OS_S16,OS_32,OS_S32]) then
            internalerror(2002090902);
          if is_shifter_const(a,imm_shift) then
            list.concat(taicpu.op_reg_const(A_MOV,reg,a))
          else if is_shifter_const(not(a),imm_shift) then
            list.concat(taicpu.op_reg_const(A_MVN,reg,not(a)))
          { loading of constants with mov and orr }
          else if (is_shifter_const(a-byte(a),imm_shift)) then
            begin
              list.concat(taicpu.op_reg_const(A_MOV,reg,a-byte(a)));
              list.concat(taicpu.op_reg_reg_const(A_ORR,reg,reg,byte(a)));
            end
          else if (is_shifter_const(a-word(a),imm_shift)) and (is_shifter_const(word(a),imm_shift)) then
            begin
              list.concat(taicpu.op_reg_const(A_MOV,reg,a-word(a)));
              list.concat(taicpu.op_reg_reg_const(A_ORR,reg,reg,word(a)));
            end
          else if (is_shifter_const(a-(dword(a) shl 8) shr 8,imm_shift)) and (is_shifter_const((dword(a) shl 8) shr 8,imm_shift)) then
            begin
              list.concat(taicpu.op_reg_const(A_MOV,reg,a-(dword(a) shl 8) shr 8));
              list.concat(taicpu.op_reg_reg_const(A_ORR,reg,reg,(dword(a) shl 8) shr 8));
            end
          else
            begin
               reference_reset(hr);

               current_asmdata.getjumplabel(l);
               cg.a_label(current_procinfo.aktlocaldata,l);
               hr.symboldata:=current_procinfo.aktlocaldata.last;
               current_procinfo.aktlocaldata.concat(tai_const.Create_32bit(longint(a)));

               hr.symbol:=l;
               list.concat(taicpu.op_reg_ref(A_LDR,reg,hr));
            end;
       end;


    function tcgarm.handle_load_store(list:TAsmList;op: tasmop;oppostfix : toppostfix;reg:tregister;ref: treference):treference;
      var
        tmpreg : tregister;
        tmpref : treference;
        l : tasmlabel;
      begin
        tmpreg:=NR_NO;

        { Be sure to have a base register }
        if (ref.base=NR_NO) then
          begin
            if ref.shiftmode<>SM_None then
              internalerror(200308294);
            ref.base:=ref.index;
            ref.index:=NR_NO;
          end;

        { absolute symbols can't be handled directly, we've to store the symbol reference
          in the text segment and access it pc relative

          For now, we assume that references where base or index equals to PC are already
          relative, all other references are assumed to be absolute and thus they need
          to be handled extra.

          A proper solution would be to change refoptions to a set and store the information
          if the symbol is absolute or relative there.
        }

        if (assigned(ref.symbol) and
            not(is_pc(ref.base)) and
            not(is_pc(ref.index))
           ) or
           { [#xxx] isn't a valid address operand }
           ((ref.base=NR_NO) and (ref.index=NR_NO)) or
           (ref.offset<-4095) or
           (ref.offset>4095) or
           ((oppostfix in [PF_SB,PF_H,PF_SH]) and
            ((ref.offset<-255) or
             (ref.offset>255)
            )
           ) or
           ((op in [A_LDF,A_STF]) and
            ((ref.offset<-1020) or
             (ref.offset>1020) or
             { the usual pc relative symbol handling assumes possible offsets of +/- 4095 }
             assigned(ref.symbol)
            )
           ) then
          begin
            reference_reset(tmpref);

            { load symbol }
            tmpreg:=getintregister(list,OS_INT);
            if assigned(ref.symbol) then
              begin
                current_asmdata.getjumplabel(l);
                cg.a_label(current_procinfo.aktlocaldata,l);
                tmpref.symboldata:=current_procinfo.aktlocaldata.last;

                current_procinfo.aktlocaldata.concat(tai_const.create_sym_offset(ref.symbol,ref.offset));

                { load consts entry }
                tmpref.symbol:=l;
                tmpref.base:=NR_R15;
                list.concat(taicpu.op_reg_ref(A_LDR,tmpreg,tmpref));

                { in case of LDF/STF, we got rid of the NR_R15 }
                if is_pc(ref.base) then
                  ref.base:=NR_NO;
                if is_pc(ref.index) then
                  ref.index:=NR_NO;
              end
            else
              a_load_const_reg(list,OS_ADDR,ref.offset,tmpreg);

            if (ref.base<>NR_NO) then
              begin
                if ref.index<>NR_NO then
                  begin
                    list.concat(taicpu.op_reg_reg_reg(A_ADD,tmpreg,ref.base,tmpreg));
                    ref.base:=tmpreg;
                  end
                else
                  begin
                    ref.index:=tmpreg;
                    ref.shiftimm:=0;
                    ref.signindex:=1;
                    ref.shiftmode:=SM_None;
                  end;
              end
            else
              ref.base:=tmpreg;
            ref.offset:=0;
            ref.symbol:=nil;
          end;

        if (ref.base<>NR_NO) and (ref.index<>NR_NO) and (ref.offset<>0) then
          begin
            if tmpreg<>NR_NO then
              a_op_const_reg_reg(list,OP_ADD,OS_ADDR,ref.offset,tmpreg,tmpreg)
            else
              begin
                tmpreg:=getintregister(list,OS_ADDR);
                a_op_const_reg_reg(list,OP_ADD,OS_ADDR,ref.offset,ref.base,tmpreg);
                ref.base:=tmpreg;
              end;
            ref.offset:=0;
          end;

        { floating point operations have only limited references
          we expect here, that a base is already set }
        if (op in [A_LDF,A_STF]) and (ref.index<>NR_NO) then
          begin
            if ref.shiftmode<>SM_none then
              internalerror(200309121);
            if tmpreg<>NR_NO then
              begin
                if ref.base=tmpreg then
                  begin
                    if ref.signindex<0 then
                      list.concat(taicpu.op_reg_reg_reg(A_SUB,tmpreg,tmpreg,ref.index))
                    else
                      list.concat(taicpu.op_reg_reg_reg(A_ADD,tmpreg,tmpreg,ref.index));
                    ref.index:=NR_NO;
                  end
                else
                  begin
                    if ref.index<>tmpreg then
                      internalerror(200403161);
                    if ref.signindex<0 then
                      list.concat(taicpu.op_reg_reg_reg(A_SUB,tmpreg,ref.base,tmpreg))
                    else
                      list.concat(taicpu.op_reg_reg_reg(A_ADD,tmpreg,ref.base,tmpreg));
                    ref.base:=tmpreg;
                    ref.index:=NR_NO;
                  end;
              end
            else
              begin
                tmpreg:=getintregister(list,OS_ADDR);
                list.concat(taicpu.op_reg_reg_reg(A_ADD,tmpreg,ref.base,ref.index));
                ref.base:=tmpreg;
                ref.index:=NR_NO;
              end;
          end;
        list.concat(setoppostfix(taicpu.op_reg_ref(op,reg,ref),oppostfix));
        Result := ref;
      end;


     procedure tcgarm.a_load_reg_ref(list : TAsmList; fromsize, tosize: tcgsize; reg : tregister;const ref : treference);
       var
         oppostfix:toppostfix;
         usedtmpref: treference;
         tmpreg : tregister;
         so : tshifterop;
         dir : integer;
       begin
         if (TCGSize2Size[FromSize] >= TCGSize2Size[ToSize]) then
           FromSize := ToSize;
         case ToSize of
           { signed integer registers }
           OS_8,
           OS_S8:
             oppostfix:=PF_B;
           OS_16,
           OS_S16:
             oppostfix:=PF_H;
           OS_32,
           OS_S32:
             oppostfix:=PF_None;
           else
             InternalError(200308295);
         end;
         if (ref.alignment in [1,2]) and (ref.alignment<tcgsize2size[tosize]) then
           begin
             if target_info.endian=endian_big then
               dir:=-1
             else
               dir:=1;
             case FromSize of
               OS_16,OS_S16:
                 begin
                   shifterop_reset(so);so.shiftmode:=SM_LSR;so.shiftimm:=8;
                   tmpreg:=getintregister(list,OS_INT);
                   usedtmpref:=ref;
                   if target_info.endian=endian_big then
                     inc(usedtmpref.offset,1);
                   usedtmpref:=a_internal_load_reg_ref(list,OS_8,OS_8,reg,usedtmpref);
                   inc(usedtmpref.offset,dir);
                   list.concat(taicpu.op_reg_reg_shifterop(A_MOV,tmpreg,reg,so));
                   a_internal_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref);
                 end;
               OS_32,OS_S32:
                 begin
                   tmpreg:=getintregister(list,OS_INT);
                   usedtmpref:=ref;
                   shifterop_reset(so);so.shiftmode:=SM_LSR;
                   if ref.alignment=2 then
                     begin
                       so.shiftimm:=16;
                       if target_info.endian=endian_big then
                         inc(usedtmpref.offset,2);
                       usedtmpref:=a_internal_load_reg_ref(list,OS_16,OS_16,reg,usedtmpref);
                       list.concat(taicpu.op_reg_reg_shifterop(A_MOV,tmpreg,reg,so));
                       inc(usedtmpref.offset,dir*2);
                       a_internal_load_reg_ref(list,OS_16,OS_16,tmpreg,usedtmpref);
                     end
                   else
                     begin
                       so.shiftimm:=8;
                       if target_info.endian=endian_big then
                         inc(usedtmpref.offset,3);
                       usedtmpref:=a_internal_load_reg_ref(list,OS_8,OS_8,reg,usedtmpref);
                       list.concat(taicpu.op_reg_reg_shifterop(A_MOV,tmpreg,reg,so));
                       inc(usedtmpref.offset,dir);
                       a_internal_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref);
                       list.concat(taicpu.op_reg_reg_shifterop(A_MOV,tmpreg,tmpreg,so));
                       inc(usedtmpref.offset,dir);
                       a_internal_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref);
                       list.concat(taicpu.op_reg_reg_shifterop(A_MOV,tmpreg,tmpreg,so));
                       inc(usedtmpref.offset,dir);
                       a_internal_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref);
                     end;
                 end
               else
                 handle_load_store(list,A_STR,oppostfix,reg,ref);
             end;
           end
         else
           handle_load_store(list,A_STR,oppostfix,reg,ref);
       end;


     procedure tcgarm.a_load_ref_reg(list : TAsmList; fromsize, tosize : tcgsize;const Ref : treference;reg : tregister);
       var
         oppostfix:toppostfix;
         usedtmpref: treference;
         tmpreg,tmpreg2 : tregister;
         so : tshifterop;
         dir : integer;
       begin
         if (TCGSize2Size[FromSize] >= TCGSize2Size[ToSize]) then
           FromSize := ToSize;
         case FromSize of
           { signed integer registers }
           OS_8:
             oppostfix:=PF_B;
           OS_S8:
             oppostfix:=PF_SB;
           OS_16:
             oppostfix:=PF_H;
           OS_S16:
             oppostfix:=PF_SH;
           OS_32,
           OS_S32:
             oppostfix:=PF_None;
           else
             InternalError(200308297);
         end;
         if (ref.alignment in [1,2]) and (ref.alignment<tcgsize2size[fromsize]) then
           begin
             if target_info.endian=endian_big then
               dir:=-1
             else
               dir:=1;
             case FromSize of
               OS_16,OS_S16:
                 begin
                   { only complicated references need an extra loadaddr }
                   if assigned(ref.symbol) or
                     (ref.index<>NR_NO) or
                     (ref.offset<-4095) or
                     (ref.offset>4094) or
                     { sometimes the compiler reused registers }
                     (reg=ref.index) or
                     (reg=ref.base) then
                     begin
                       tmpreg2:=getintregister(list,OS_INT);
                       a_loadaddr_ref_reg(list,ref,tmpreg2);
                       reference_reset_base(usedtmpref,tmpreg2,0);
                     end
                   else
                     usedtmpref:=ref;

                   if target_info.endian=endian_big then
                     inc(usedtmpref.offset,1);
                   shifterop_reset(so);so.shiftmode:=SM_LSL;so.shiftimm:=8;
                   tmpreg:=getintregister(list,OS_INT);
                   a_internal_load_ref_reg(list,OS_8,OS_8,usedtmpref,reg);
                   inc(usedtmpref.offset,dir);
                   if FromSize=OS_16 then
                     a_internal_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg)
                   else
                     a_internal_load_ref_reg(list,OS_S8,OS_S8,usedtmpref,tmpreg);
                   list.concat(taicpu.op_reg_reg_reg_shifterop(A_ORR,reg,reg,tmpreg,so));
                 end;
               OS_32,OS_S32:
                 begin
                   tmpreg:=getintregister(list,OS_INT);

                   { only complicated references need an extra loadaddr }
                   if assigned(ref.symbol) or
                     (ref.index<>NR_NO) or
                     (ref.offset<-4095) or
                     (ref.offset>4092) or
                     { sometimes the compiler reused registers }
                     (reg=ref.index) or
                     (reg=ref.base) then
                     begin
                       tmpreg2:=getintregister(list,OS_INT);
                       a_loadaddr_ref_reg(list,ref,tmpreg2);
                       reference_reset_base(usedtmpref,tmpreg2,0);
                     end
                   else
                     usedtmpref:=ref;

                   shifterop_reset(so);so.shiftmode:=SM_LSL;
                   if ref.alignment=2 then
                     begin
                       if target_info.endian=endian_big then
                         inc(usedtmpref.offset,2);
                       a_internal_load_ref_reg(list,OS_16,OS_16,usedtmpref,reg);
                       inc(usedtmpref.offset,dir*2);
                       a_internal_load_ref_reg(list,OS_16,OS_16,usedtmpref,tmpreg);
                       so.shiftimm:=16;
                       list.concat(taicpu.op_reg_reg_reg_shifterop(A_ORR,reg,reg,tmpreg,so));
                     end
                   else
                     begin
                       if target_info.endian=endian_big then
                         inc(usedtmpref.offset,3);
                       a_internal_load_ref_reg(list,OS_8,OS_8,usedtmpref,reg);
                       inc(usedtmpref.offset,dir);
                       a_internal_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg);
                       so.shiftimm:=8;
                       list.concat(taicpu.op_reg_reg_reg_shifterop(A_ORR,reg,reg,tmpreg,so));
                       inc(usedtmpref.offset,dir);
                       a_internal_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg);
                       so.shiftimm:=16;
                       list.concat(taicpu.op_reg_reg_reg_shifterop(A_ORR,reg,reg,tmpreg,so));
                       inc(usedtmpref.offset,dir);
                       a_internal_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg);
                       so.shiftimm:=24;
                       list.concat(taicpu.op_reg_reg_reg_shifterop(A_ORR,reg,reg,tmpreg,so));
                     end;
                 end
               else
                 handle_load_store(list,A_LDR,oppostfix,reg,ref);
             end;
           end
         else
           handle_load_store(list,A_LDR,oppostfix,reg,ref);

         if (fromsize=OS_S8) and (tosize = OS_16) then
           a_load_reg_reg(list,OS_16,OS_32,reg,reg);
       end;


     function tcgarm.a_internal_load_reg_ref(list : TAsmList; fromsize, tosize: tcgsize; reg : tregister;const ref : treference):treference;
       var
         oppostfix:toppostfix;
       begin
         case ToSize of
           { signed integer registers }
           OS_8,
           OS_S8:
             oppostfix:=PF_B;
           OS_16,
           OS_S16:
             oppostfix:=PF_H;
           OS_32,
           OS_S32:
             oppostfix:=PF_None;
           else
             InternalError(2003082910);
         end;
         result:=handle_load_store(list,A_STR,oppostfix,reg,ref);
       end;


     function tcgarm.a_internal_load_ref_reg(list : TAsmList; fromsize, tosize : tcgsize;const Ref : treference;reg : tregister):treference;
       var
         oppostfix:toppostfix;
       begin
         case FromSize of
           { signed integer registers }
           OS_8:
             oppostfix:=PF_B;
           OS_S8:
             oppostfix:=PF_SB;
           OS_16:
             oppostfix:=PF_H;
           OS_S16:
             oppostfix:=PF_SH;
           OS_32,
           OS_S32:
             oppostfix:=PF_None;
           else
             InternalError(200308291);
         end;
         result:=handle_load_store(list,A_LDR,oppostfix,reg,ref);
       end;

     procedure tcgarm.a_load_reg_reg(list : TAsmList; fromsize, tosize : tcgsize;reg1,reg2 : tregister);
       var
         so : tshifterop;

       procedure do_shift(shiftmode : tshiftmode; shiftimm : byte; reg : tregister);
         begin
           so.shiftmode:=shiftmode;
           so.shiftimm:=shiftimm;
           list.concat(taicpu.op_reg_reg_shifterop(A_MOV,reg2,reg,so));
         end;

       var
         instr: taicpu;
         conv_done: boolean;
       begin
         if (tcgsize2size[fromsize]>32) or (tcgsize2size[tosize]>32) or (fromsize=OS_NO) or (tosize=OS_NO) then
           internalerror(2002090901);

         conv_done:=false;
         if tosize<>fromsize then
           begin
             shifterop_reset(so);
             conv_done:=true;
             if tcgsize2size[tosize]<=tcgsize2size[fromsize] then
               fromsize:=tosize;
             case fromsize of
               OS_8:
                 list.concat(taicpu.op_reg_reg_const(A_AND,reg2,reg1,$ff));
               OS_S8:
                 begin
                   do_shift(SM_LSL,24,reg1);
                   if tosize=OS_16 then
                     begin
                       do_shift(SM_ASR,8,reg2);
                       do_shift(SM_LSR,16,reg2);
                     end
                   else
                     do_shift(SM_ASR,24,reg2);
                 end;
               OS_16:
                 begin
                   do_shift(SM_LSL,16,reg1);
                   do_shift(SM_LSR,16,reg2);
                 end;
               OS_S16:
                 begin
                   do_shift(SM_LSL,16,reg1);
                   do_shift(SM_ASR,16,reg2)
                 end;
               else
                 conv_done:=false;
             end;
           end;
         if not conv_done and (reg1<>reg2) then
           begin
             { same size, only a register mov required }
             instr:=taicpu.op_reg_reg(A_MOV,reg2,reg1);
             list.Concat(instr);
             { Notify the register allocator that we have written a move instruction so
               it can try to eliminate it. }
             add_move_instruction(instr);
           end;
       end;


    procedure tcgarm.a_paramfpu_ref(list : TAsmList;size : tcgsize;const ref : treference;const paraloc : TCGPara);
      var
         href,href2 : treference;
         hloc : pcgparalocation;
      begin
        href:=ref;
        hloc:=paraloc.location;
        while assigned(hloc) do
          begin
            case hloc^.loc of
              LOC_FPUREGISTER,LOC_CFPUREGISTER:
                a_loadfpu_ref_reg(list,size,size,ref,hloc^.register);
              LOC_REGISTER :
                case hloc^.size of
                  OS_F32:
                    a_load_ref_reg(list,OS_32,OS_32,href,hloc^.register);
                  OS_64,
                  OS_F64:
                    cg64.a_param64_ref(list,href,paraloc);
                  else
                    a_load_ref_reg(list,hloc^.size,hloc^.size,href,hloc^.register);
                end;
              LOC_REFERENCE :
                begin
                  reference_reset_base(href2,hloc^.reference.index,hloc^.reference.offset);
                  { concatcopy should choose the best way to copy the data }
                  g_concatcopy(list,href,href2,tcgsize2size[size]);
                end;
              else
                internalerror(200408241);
           end;
           inc(href.offset,tcgsize2size[hloc^.size]);
           hloc:=hloc^.next;
         end;
      end;


     procedure tcgarm.a_loadfpu_reg_reg(list: TAsmList; fromsize,tosize: tcgsize; reg1, reg2: tregister);
       begin
         list.concat(setoppostfix(taicpu.op_reg_reg(A_MVF,reg2,reg1),cgsize2fpuoppostfix[tosize]));
       end;


     procedure tcgarm.a_loadfpu_ref_reg(list: TAsmList; fromsize,tosize: tcgsize; const ref: treference; reg: tregister);
       var
         oppostfix:toppostfix;
       begin
         case fromsize of
           OS_32,
           OS_F32:
             oppostfix:=PF_S;
           OS_64,
           OS_F64:
             oppostfix:=PF_D;
           OS_F80:
             oppostfix:=PF_E;
           else
             InternalError(200309021);
         end;
         handle_load_store(list,A_LDF,oppostfix,reg,ref);
         if fromsize<>tosize then
           a_loadfpu_reg_reg(list,fromsize,tosize,reg,reg);
       end;


     procedure tcgarm.a_loadfpu_reg_ref(list: TAsmList; fromsize, tosize: tcgsize; reg: tregister; const ref: treference);
       var
         oppostfix:toppostfix;
       begin
         case tosize of
           OS_F32:
             oppostfix:=PF_S;
           OS_F64:
             oppostfix:=PF_D;
           OS_F80:
             oppostfix:=PF_E;
           else
             InternalError(200309022);
         end;
         handle_load_store(list,A_STF,oppostfix,reg,ref);
       end;


    {  comparison operations }
    procedure tcgarm.a_cmp_const_reg_label(list : TAsmList;size : tcgsize;cmp_op : topcmp;a : aint;reg : tregister;
      l : tasmlabel);
      var
        tmpreg : tregister;
        b : byte;
      begin
        if is_shifter_const(a,b) then
          list.concat(taicpu.op_reg_const(A_CMP,reg,a))
        { CMN reg,0 and CMN reg,$80000000 are different from CMP reg,$ffffffff
          and CMP reg,$7fffffff regarding the flags according to the ARM manual }
        else if (a<>$7fffffff) and (a<>-1) and is_shifter_const(-a,b) then
          list.concat(taicpu.op_reg_const(A_CMN,reg,-a))
        else
          begin
            tmpreg:=getintregister(list,size);
            a_load_const_reg(list,size,a,tmpreg);
            list.concat(taicpu.op_reg_reg(A_CMP,reg,tmpreg));
          end;
        a_jmp_cond(list,cmp_op,l);
      end;


    procedure tcgarm.a_cmp_reg_reg_label(list : TAsmList;size : tcgsize;cmp_op : topcmp;reg1,reg2 : tregister;l : tasmlabel);
      begin
        list.concat(taicpu.op_reg_reg(A_CMP,reg2,reg1));
        a_jmp_cond(list,cmp_op,l);
      end;


    procedure tcgarm.a_jmp_name(list : TAsmList;const s : string);
      var
        ai : taicpu;
      begin
        ai:=taicpu.op_sym(A_B,current_asmdata.RefAsmSymbol(s));
        ai.is_jmp:=true;
        list.concat(ai);
      end;


    procedure tcgarm.a_jmp_always(list : TAsmList;l: tasmlabel);
      var
        ai : taicpu;
      begin
        ai:=taicpu.op_sym(A_B,l);
        ai.is_jmp:=true;
        list.concat(ai);
      end;


    procedure tcgarm.a_jmp_flags(list : TAsmList;const f : TResFlags;l: tasmlabel);
      var
        ai : taicpu;
      begin
        ai:=setcondition(taicpu.op_sym(A_B,l),flags_to_cond(f));
        ai.is_jmp:=true;
        list.concat(ai);
      end;


    procedure tcgarm.g_flags2reg(list: TAsmList; size: TCgSize; const f: TResFlags; reg: TRegister);
      begin
        list.concat(setcondition(taicpu.op_reg_const(A_MOV,reg,1),flags_to_cond(f)));
        list.concat(setcondition(taicpu.op_reg_const(A_MOV,reg,0),inverse_cond(flags_to_cond(f))));
      end;


    procedure tcgarm.g_proc_entry(list : TAsmList;localsize : longint;nostackframe:boolean);
      var
         ref : treference;
         shift : byte;
         firstfloatreg,lastfloatreg,
         r : byte;
         regs : tcpuregisterset;
      begin
        LocalSize:=align(LocalSize,4);
        if not(nostackframe) then
          begin
            firstfloatreg:=RS_NO;
            { save floating point registers? }
            for r:=RS_F0 to RS_F7 do
              if r in rg[R_FPUREGISTER].used_in_proc-paramanager.get_volatile_registers_fpu(pocall_stdcall) then
                begin
                  if firstfloatreg=RS_NO then
                    firstfloatreg:=r;
                  lastfloatreg:=r;
                end;
            a_reg_alloc(list,NR_STACK_POINTER_REG);
            if current_procinfo.framepointer<>NR_STACK_POINTER_REG then
              begin
                a_reg_alloc(list,NR_FRAME_POINTER_REG);
                a_reg_alloc(list,NR_R12);

                list.concat(taicpu.op_reg_reg(A_MOV,NR_R12,NR_STACK_POINTER_REG));
              end;
            { save int registers }
            reference_reset(ref);
            ref.index:=NR_STACK_POINTER_REG;
            ref.addressmode:=AM_PREINDEXED;
            regs:=rg[R_INTREGISTER].used_in_proc-paramanager.get_volatile_registers_int(pocall_stdcall);
            if current_procinfo.framepointer<>NR_STACK_POINTER_REG then
              regs:=regs+[RS_R11,RS_R12,RS_R14,RS_R15]
            else
              if (regs<>[]) or (pi_do_call in current_procinfo.flags) then
                include(regs,RS_R14);
            if regs<>[] then
              list.concat(setoppostfix(taicpu.op_ref_regset(A_STM,ref,regs),PF_FD));

            if current_procinfo.framepointer<>NR_STACK_POINTER_REG then
              list.concat(taicpu.op_reg_reg_const(A_SUB,NR_FRAME_POINTER_REG,NR_R12,4));

           (* allocate necessary stack size
              not necessary according to Yury Sidorov

            { don't use a_op_const_reg_reg here because we don't allow register allocations
              in the entry/exit code }
           if (target_info.system in [system_arm_wince]) and
              (localsize>=winstackpagesize) then
             begin
               if localsize div winstackpagesize<=5 then
                 begin
                    if is_shifter_const(localsize,shift) then
                      list.concat(Taicpu.op_reg_reg_const(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,localsize))
                    else
                      begin
                        a_load_const_reg(list,OS_ADDR,localsize,NR_R12);
                        list.concat(taicpu.op_reg_reg_reg(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,NR_R12));
                      end;

                    for i:=1 to localsize div winstackpagesize do
                      begin
                        if localsize-i*winstackpagesize<4096 then
                          reference_reset_base(href,NR_STACK_POINTER_REG,-(localsize-i*winstackpagesize))
                        else
                          begin
                            a_load_const_reg(list,OS_ADDR,-(localsize-i*winstackpagesize),NR_R12);
                            reference_reset_base(href,NR_STACK_POINTER_REG,0);
                            href.index:=NR_R12;
                          end;
                        { the data stored doesn't matter }
                        list.concat(Taicpu.op_reg_ref(A_STR,NR_R0,href));
                      end;
                    a_reg_dealloc(list,NR_R12);
                    reference_reset_base(href,NR_STACK_POINTER_REG,0);
                    { the data stored doesn't matter }
                    list.concat(Taicpu.op_reg_ref(A_STR,NR_R0,href));
                 end
               else
                 begin
                    current_asmdata.getjumplabel(again);
                    list.concat(Taicpu.op_reg_const(A_MOV,NR_R12,localsize div winstackpagesize));
                    a_label(list,again);
                    { always shifterop }
                    list.concat(Taicpu.op_reg_reg_const(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,winstackpagesize));
                    reference_reset_base(href,NR_STACK_POINTER_REG,0);
                    { the data stored doesn't matter }
                    list.concat(Taicpu.op_reg_ref(A_STR,NR_R0,href));
                    list.concat(Taicpu.op_reg_reg_const(A_SUB,NR_R12,NR_R12,1));
                    a_jmp_cond(list,OC_NE,again);
                    if is_shifter_const(localsize mod winstackpagesize,shift) then
                      list.concat(Taicpu.op_reg_reg_const(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,localsize mod winstackpagesize))
                    else
                      begin
                        a_load_const_reg(list,OS_ADDR,localsize mod winstackpagesize,NR_R12);
                        list.concat(taicpu.op_reg_reg_reg(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,NR_R12));
                      end;
                    a_reg_dealloc(list,NR_R12);
                    reference_reset_base(href,NR_STACK_POINTER_REG,0);
                    { the data stored doesn't matter }
                    list.concat(Taicpu.op_reg_ref(A_STR,NR_R0,href));
                 end
             end
            else
            *)
            if LocalSize<>0 then
              if not(is_shifter_const(localsize,shift)) then
                begin
                  if current_procinfo.framepointer=NR_STACK_POINTER_REG then
                    a_reg_alloc(list,NR_R12);
                  a_load_const_reg(list,OS_ADDR,LocalSize,NR_R12);
                  list.concat(taicpu.op_reg_reg_reg(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,NR_R12));
                  a_reg_dealloc(list,NR_R12);
                end
              else
                begin
                  a_reg_dealloc(list,NR_R12);
                  list.concat(taicpu.op_reg_reg_const(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,LocalSize));
                end;

            if firstfloatreg<>RS_NO then
              begin
                reference_reset(ref);
                if tg.direction*tarmprocinfo(current_procinfo).floatregstart>=1023 then
                  begin
                    a_load_const_reg(list,OS_ADDR,-tarmprocinfo(current_procinfo).floatregstart,NR_R12);
                    list.concat(taicpu.op_reg_reg_reg(A_SUB,NR_R12,current_procinfo.framepointer,NR_R12));
                    ref.base:=NR_R12;
                  end
                else
                  begin
                    ref.base:=current_procinfo.framepointer;
                    ref.offset:=tarmprocinfo(current_procinfo).floatregstart;
                  end;
                list.concat(taicpu.op_reg_const_ref(A_SFM,newreg(R_FPUREGISTER,firstfloatreg,R_SUBWHOLE),
                  lastfloatreg-firstfloatreg+1,ref));
              end;
          end;
      end;


    procedure tcgarm.g_proc_exit(list : TAsmList;parasize : longint;nostackframe:boolean);
      var
         ref : treference;
         firstfloatreg,lastfloatreg,
         r : byte;
         shift : byte;
         regs : tcpuregisterset;
         LocalSize : longint;
      begin
        if not(nostackframe) then
          begin
            { restore floating point register }
            firstfloatreg:=RS_NO;
            { save floating point registers? }
            for r:=RS_F0 to RS_F7 do
              if r in rg[R_FPUREGISTER].used_in_proc-paramanager.get_volatile_registers_fpu(pocall_stdcall) then
                begin
                  if firstfloatreg=RS_NO then
                    firstfloatreg:=r;
                  lastfloatreg:=r;
                end;

            if firstfloatreg<>RS_NO then
              begin
                reference_reset(ref);
                if tg.direction*tarmprocinfo(current_procinfo).floatregstart>=1023 then
                  begin
                    a_load_const_reg(list,OS_ADDR,-tarmprocinfo(current_procinfo).floatregstart,NR_R12);
                    list.concat(taicpu.op_reg_reg_reg(A_SUB,NR_R12,current_procinfo.framepointer,NR_R12));
                    ref.base:=NR_R12;
                  end
                else
                  begin
                    ref.base:=current_procinfo.framepointer;
                    ref.offset:=tarmprocinfo(current_procinfo).floatregstart;
                  end;
                list.concat(taicpu.op_reg_const_ref(A_LFM,newreg(R_FPUREGISTER,firstfloatreg,R_SUBWHOLE),
                  lastfloatreg-firstfloatreg+1,ref));
              end;

            if (current_procinfo.framepointer=NR_STACK_POINTER_REG) then
              begin
                LocalSize:=current_procinfo.calc_stackframe_size;
                if LocalSize<>0 then
                  if not(is_shifter_const(LocalSize,shift)) then
                    begin
                      a_reg_alloc(list,NR_R12);
                      a_load_const_reg(list,OS_ADDR,LocalSize,NR_R12);
                      list.concat(taicpu.op_reg_reg_reg(A_ADD,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,NR_R12));
                      a_reg_dealloc(list,NR_R12);
                    end
                  else
                    begin
                      list.concat(taicpu.op_reg_reg_const(A_ADD,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,LocalSize));
                    end;

                regs:=rg[R_INTREGISTER].used_in_proc-paramanager.get_volatile_registers_int(pocall_stdcall);
                if (pi_do_call in current_procinfo.flags) or (regs<>[]) then
                  begin
                    exclude(regs,RS_R14);
                    include(regs,RS_R15);
                  end;
                if regs=[] then
                  list.concat(taicpu.op_reg_reg(A_MOV,NR_R15,NR_R14))
                else
                  begin
                    reference_reset(ref);
                    ref.index:=NR_STACK_POINTER_REG;
                    ref.addressmode:=AM_PREINDEXED;
                    list.concat(setoppostfix(taicpu.op_ref_regset(A_LDM,ref,regs),PF_FD));
                  end;
              end
            else
              begin
                { restore int registers and return }
                reference_reset(ref);
                ref.index:=NR_FRAME_POINTER_REG;
                list.concat(setoppostfix(taicpu.op_ref_regset(A_LDM,ref,rg[R_INTREGISTER].used_in_proc-paramanager.get_volatile_registers_int(pocall_stdcall)+[RS_R11,RS_R13,RS_R15]),PF_EA));
              end;
          end
        else
          list.concat(taicpu.op_reg_reg(A_MOV,NR_PC,NR_R14));
      end;


    procedure tcgarm.a_loadaddr_ref_reg(list : TAsmList;const ref : treference;r : tregister);
      var
        b : byte;
        tmpref : treference;
        instr : taicpu;
      begin
        if ref.addressmode<>AM_OFFSET then
          internalerror(200309071);
        tmpref:=ref;
        { Be sure to have a base register }
        if (tmpref.base=NR_NO) then
          begin
            if tmpref.shiftmode<>SM_None then
              internalerror(200308294);
            if tmpref.signindex<0 then
              internalerror(200312023);
            tmpref.base:=tmpref.index;
            tmpref.index:=NR_NO;
          end;

        if assigned(tmpref.symbol) or
           not((is_shifter_const(tmpref.offset,b)) or
               (is_shifter_const(-tmpref.offset,b))
              ) then
          fixref(list,tmpref);

        { expect a base here if there is an index }
        if (tmpref.base=NR_NO) and (tmpref.index<>NR_NO) then
          internalerror(200312022);

        if tmpref.index<>NR_NO then
          begin
            if tmpref.shiftmode<>SM_None then
              internalerror(200312021);
            if tmpref.signindex<0 then
              a_op_reg_reg_reg(list,OP_SUB,OS_ADDR,tmpref.base,tmpref.index,r)
            else
              a_op_reg_reg_reg(list,OP_ADD,OS_ADDR,tmpref.base,tmpref.index,r);
            if tmpref.offset<>0 then
              a_op_const_reg_reg(list,OP_ADD,OS_ADDR,tmpref.offset,r,r);
          end
        else
          begin
            if tmpref.base=NR_NO then
              a_load_const_reg(list,OS_ADDR,tmpref.offset,r)
            else
              if tmpref.offset<>0 then
                a_op_const_reg_reg(list,OP_ADD,OS_ADDR,tmpref.offset,tmpref.base,r)
              else
                begin
                  instr:=taicpu.op_reg_reg(A_MOV,r,tmpref.base);
                  list.concat(instr);
                  add_move_instruction(instr);
                end;
          end;
      end;


    procedure tcgarm.fixref(list : TAsmList;var ref : treference);
      var
        tmpreg : tregister;
        tmpref : treference;
        l : tasmlabel;
      begin
        { absolute symbols can't be handled directly, we've to store the symbol reference
          in the text segment and access it pc relative

          For now, we assume that references where base or index equals to PC are already
          relative, all other references are assumed to be absolute and thus they need
          to be handled extra.

          A proper solution would be to change refoptions to a set and store the information
          if the symbol is absolute or relative there.
        }
        { create consts entry }
        reference_reset(tmpref);
        current_asmdata.getjumplabel(l);
        cg.a_label(current_procinfo.aktlocaldata,l);
        tmpref.symboldata:=current_procinfo.aktlocaldata.last;

        if assigned(ref.symbol) then
          current_procinfo.aktlocaldata.concat(tai_const.create_sym_offset(ref.symbol,ref.offset))
        else
          current_procinfo.aktlocaldata.concat(tai_const.Create_32bit(ref.offset));

        { load consts entry }
        tmpreg:=getintregister(list,OS_INT);
        tmpref.symbol:=l;
        tmpref.base:=NR_PC;
        list.concat(taicpu.op_reg_ref(A_LDR,tmpreg,tmpref));

        if (ref.base<>NR_NO) then
          begin
            if ref.index<>NR_NO then
              begin
                list.concat(taicpu.op_reg_reg_reg(A_ADD,tmpreg,ref.base,tmpreg));
                ref.base:=tmpreg;
              end
            else
              if ref.base<>NR_PC then
                begin
                  ref.index:=tmpreg;
                  ref.shiftimm:=0;
                  ref.signindex:=1;
                  ref.shiftmode:=SM_None;
                end
                else
                  ref.base:=tmpreg;
          end
        else
          ref.base:=tmpreg;
        ref.offset:=0;
        ref.symbol:=nil;
      end;


    procedure tcgarm.g_concatcopy_move(list : TAsmList;const source,dest : treference;len : aint);
      var
        paraloc1,paraloc2,paraloc3 : TCGPara;
      begin
        paraloc1.init;
        paraloc2.init;
        paraloc3.init;
        paramanager.getintparaloc(pocall_default,1,paraloc1);
        paramanager.getintparaloc(pocall_default,2,paraloc2);
        paramanager.getintparaloc(pocall_default,3,paraloc3);
        paramanager.allocparaloc(list,paraloc3);
        a_param_const(list,OS_INT,len,paraloc3);
        paramanager.allocparaloc(list,paraloc2);
        a_paramaddr_ref(list,dest,paraloc2);
        paramanager.allocparaloc(list,paraloc2);
        a_paramaddr_ref(list,source,paraloc1);
        paramanager.freeparaloc(list,paraloc3);
        paramanager.freeparaloc(list,paraloc2);
        paramanager.freeparaloc(list,paraloc1);
        alloccpuregisters(list,R_INTREGISTER,paramanager.get_volatile_registers_int(pocall_default));
        alloccpuregisters(list,R_FPUREGISTER,paramanager.get_volatile_registers_fpu(pocall_default));
        a_call_name(list,'FPC_MOVE');
        dealloccpuregisters(list,R_FPUREGISTER,paramanager.get_volatile_registers_fpu(pocall_default));
        dealloccpuregisters(list,R_INTREGISTER,paramanager.get_volatile_registers_int(pocall_default));
        paraloc3.done;
        paraloc2.done;
        paraloc1.done;
      end;


    procedure tcgarm.g_concatcopy_internal(list : TAsmList;const source,dest : treference;len : aint;aligned : boolean);
      const
        maxtmpreg=10;{roozbeh: can be reduced to 8 or lower if might conflick with reserved ones,also +2 is used becouse of regs required for referencing}

      var
        srcref,dstref,usedtmpref,usedtmpref2:treference;
        srcreg,destreg,countreg,r,tmpreg:tregister;
        helpsize:aint;
        copysize:byte;
        cgsize:Tcgsize;
        tmpregisters:array[1..maxtmpreg] of tregister;
        tmpregi,tmpregi2:byte;

      { will never be called with count<=4 }
      procedure genloop(count : aword;size : byte);
        const
          size2opsize : array[1..4] of tcgsize = (OS_8,OS_16,OS_NO,OS_32);
        var
          l : tasmlabel;
        begin
          current_asmdata.getjumplabel(l);
          if count<size then size:=1;
          a_load_const_reg(list,OS_INT,count div size,countreg);
          cg.a_label(list,l);
          srcref.addressmode:=AM_POSTINDEXED;
          dstref.addressmode:=AM_POSTINDEXED;
          srcref.offset:=size;
          dstref.offset:=size;
          r:=getintregister(list,size2opsize[size]);
          a_load_ref_reg(list,size2opsize[size],size2opsize[size],srcref,r);
          list.concat(setoppostfix(taicpu.op_reg_reg_const(A_SUB,countreg,countreg,1),PF_S));
          a_load_reg_ref(list,size2opsize[size],size2opsize[size],r,dstref);
          a_jmp_flags(list,F_NE,l);
          srcref.offset:=1;
          dstref.offset:=1;
          case count mod size of
            1:
              begin
                a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                a_load_reg_ref(list,OS_8,OS_8,r,dstref);
              end;
            2:
              if aligned then
                begin
                  a_load_ref_reg(list,OS_16,OS_16,srcref,r);
                  a_load_reg_ref(list,OS_16,OS_16,r,dstref);
                end
              else
                begin
                  a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref);
                  a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref);
                end;
            3:
              if aligned then
                begin
                  srcref.offset:=2;
                  dstref.offset:=2;
                  a_load_ref_reg(list,OS_16,OS_16,srcref,r);
                  a_load_reg_ref(list,OS_16,OS_16,r,dstref);
                  a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref);
                end
              else
                begin
                  a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref);
                  a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref);
                  a_load_ref_reg(list,OS_8,OS_8,srcref,r);
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref);
                end;
          end;
          { keep the registers alive }
          list.concat(taicpu.op_reg_reg(A_MOV,countreg,countreg));
          list.concat(taicpu.op_reg_reg(A_MOV,srcreg,srcreg));
          list.concat(taicpu.op_reg_reg(A_MOV,destreg,destreg));
        end;

      begin
        if len=0 then
          exit;
        helpsize:=12+maxtmpreg*4;//52 with maxtmpreg=10
        dstref:=dest;
        srcref:=source;
        if cs_opt_size in current_settings.optimizerswitches then
          helpsize:=8;
        if (len<=helpsize) and aligned then
          begin
            tmpregi:=0;
            srcreg:=getintregister(list,OS_ADDR);

            { explicit pc relative addressing, could be
              e.g. a floating point constant }
            if source.base=NR_PC then
              begin
                { ... then we don't need a loadaddr }
                srcref:=source;
              end
            else
              begin
                a_loadaddr_ref_reg(list,source,srcreg);
                reference_reset_base(srcref,srcreg,0);
              end;

            while (len div 4 <> 0) and (tmpregi<maxtmpreg) do
              begin
                inc(tmpregi);
                tmpregisters[tmpregi]:=getintregister(list,OS_32);
                a_load_ref_reg(list,OS_32,OS_32,srcref,tmpregisters[tmpregi]);
                inc(srcref.offset,4);
                dec(len,4);
              end;

            destreg:=getintregister(list,OS_ADDR);
            a_loadaddr_ref_reg(list,dest,destreg);
            reference_reset_base(dstref,destreg,0);
            tmpregi2:=1;
            while (tmpregi2<=tmpregi) do
              begin
                a_load_reg_ref(list,OS_32,OS_32,tmpregisters[tmpregi2],dstref);
                inc(dstref.offset,4);
                inc(tmpregi2);
              end;

            copysize:=4;
            cgsize:=OS_32;
            while len<>0 do
              begin
                if len<2 then
                  begin
                    copysize:=1;
                    cgsize:=OS_8;
                  end
                else if len<4 then
                  begin
                    copysize:=2;
                    cgsize:=OS_16;
                  end;
                dec(len,copysize);
                r:=getintregister(list,cgsize);
                a_load_ref_reg(list,cgsize,cgsize,srcref,r);
                a_load_reg_ref(list,cgsize,cgsize,r,dstref);
                inc(srcref.offset,copysize);
                inc(dstref.offset,copysize);
              end;{end of while}
          end
        else
          begin
            cgsize:=OS_32;
            if (len<=4) then{len<=4 and not aligned}
              begin
                r:=getintregister(list,cgsize);
                usedtmpref:=a_internal_load_ref_reg(list,OS_8,OS_8,srcref,r);
                if Len=1 then
                  a_load_reg_ref(list,OS_8,OS_8,r,dstref)
                else
                  begin
                    tmpreg:=getintregister(list,cgsize);
                    usedtmpref2:=a_internal_load_reg_ref(list,OS_8,OS_8,r,dstref);
                    inc(usedtmpref.offset,1);
                    a_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg);
                    inc(usedtmpref2.offset,1);
                    a_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref2);
                    if len>2 then
                      begin
                        inc(usedtmpref.offset,1);
                        a_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg);
                        inc(usedtmpref2.offset,1);
                        a_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref2);
                        if len>3 then
                          begin
                            inc(usedtmpref.offset,1);
                            a_load_ref_reg(list,OS_8,OS_8,usedtmpref,tmpreg);
                            inc(usedtmpref2.offset,1);
                            a_load_reg_ref(list,OS_8,OS_8,tmpreg,usedtmpref2);
                          end;
                        end;
                      end;
            end{end of if len<=4}
            else
              begin{unaligned & 4<len<helpsize **or** aligned/unaligned & len>helpsize}
                destreg:=getintregister(list,OS_ADDR);
                a_loadaddr_ref_reg(list,dest,destreg);
                reference_reset_base(dstref,destreg,0);

                srcreg:=getintregister(list,OS_ADDR);
                a_loadaddr_ref_reg(list,source,srcreg);
                reference_reset_base(srcref,srcreg,0);

                countreg:=getintregister(list,OS_32);

//            if cs_opt_size in current_settings.optimizerswitches  then
                { roozbeh : it seems loading 1 byte is faster becouse of caching/fetching(?) }
                {if aligned then
                genloop(len,4)
                else}
                genloop(len,1);
            end;
          end;
    end;

    procedure tcgarm.g_concatcopy_unaligned(list : TAsmList;const source,dest : treference;len : aint);
      begin
        g_concatcopy_internal(list,source,dest,len,false);
      end;


    procedure tcgarm.g_concatcopy(list : TAsmList;const source,dest : treference;len : aint);
      begin
        if (source.alignment in [1..3]) or
          (dest.alignment in [1..3]) then
          g_concatcopy_internal(list,source,dest,len,false)
        else
          g_concatcopy_internal(list,source,dest,len,true);
      end;


    procedure tcgarm.g_overflowCheck(list : TAsmList;const l : tlocation;def : tdef);
      var
        ovloc : tlocation;
      begin
        ovloc.loc:=LOC_VOID;
        g_overflowCheck_loc(list,l,def,ovloc);
      end;


    procedure tcgarm.g_overflowCheck_loc(List:TAsmList;const Loc:TLocation;def:TDef;ovloc : tlocation);
      var
        hl : tasmlabel;
        ai:TAiCpu;
        hflags : tresflags;
      begin
        if not(cs_check_overflow in current_settings.localswitches) then
          exit;
        current_asmdata.getjumplabel(hl);
        case ovloc.loc of
          LOC_VOID:
            begin
              ai:=taicpu.op_sym(A_B,hl);
              ai.is_jmp:=true;

              if not((def.typ=pointerdef) or
                    ((def.typ=orddef) and
                     (torddef(def).ordtype in [u64bit,u16bit,u32bit,u8bit,uchar,pasbool]))) then
                 ai.SetCondition(C_VC)
              else
                if TAiCpu(List.Last).opcode in [A_RSB,A_RSC,A_SBC,A_SUB] then
                  ai.SetCondition(C_CS)
                else
                  ai.SetCondition(C_CC);

              list.concat(ai);
            end;
          LOC_FLAGS:
            begin
              hflags:=ovloc.resflags;
              inverse_flags(hflags);
              cg.a_jmp_flags(list,hflags,hl);
            end;
          else
            internalerror(200409281);
        end;

        a_call_name(list,'FPC_OVERFLOW');
        a_label(list,hl);
      end;


    procedure tcgarm.g_save_registers(list : TAsmList);
      begin
        { this work is done in g_proc_entry }
      end;


    procedure tcgarm.g_restore_registers(list : TAsmList);
      begin
        { this work is done in g_proc_exit }
      end;


    procedure tcgarm.a_jmp_cond(list : TAsmList;cond : TOpCmp;l: tasmlabel);
      var
        ai : taicpu;
      begin
        ai:=Taicpu.Op_sym(A_B,l);
        ai.SetCondition(OpCmp2AsmCond[cond]);
        ai.is_jmp:=true;
        list.concat(ai);
      end;


    procedure tcgarm.g_adjust_self_value(list:TAsmList;procdef: tprocdef;ioffset: aint);
      var
        hsym : tsym;
        href : treference;
        paraloc : Pcgparalocation;
        shift : byte;
      begin
        { calculate the parameter info for the procdef }
        if not procdef.has_paraloc_info then
          begin
            procdef.requiredargarea:=paramanager.create_paraloc_info(procdef,callerside);
            procdef.has_paraloc_info:=true;
          end;
        hsym:=tsym(procdef.parast.Find('self'));
        if not(assigned(hsym) and
          (hsym.typ=paravarsym)) then
          internalerror(200305251);
        paraloc:=tparavarsym(hsym).paraloc[callerside].location;
        while paraloc<>nil do
          with paraloc^ do
            begin
              case loc of
                LOC_REGISTER:
                  begin
                    if is_shifter_const(ioffset,shift) then
                      a_op_const_reg(list,OP_SUB,size,ioffset,register)
                    else
                      begin
                        a_load_const_reg(list,OS_ADDR,ioffset,NR_R12);
                        a_op_reg_reg(list,OP_SUB,size,NR_R12,register);
                      end;
                  end;
                LOC_REFERENCE:
                  begin
                    { offset in the wrapper needs to be adjusted for the stored
                      return address }
                    reference_reset_base(href,reference.index,reference.offset+sizeof(aint));
                    if is_shifter_const(ioffset,shift) then
                      a_op_const_ref(list,OP_SUB,size,ioffset,href)
                    else
                      begin
                        a_load_const_reg(list,OS_ADDR,ioffset,NR_R12);
                        a_op_reg_ref(list,OP_SUB,size,NR_R12,href);
                      end;
                  end
                else
                  internalerror(200309189);
              end;
              paraloc:=next;
            end;
      end;

    procedure tcgarm.g_stackpointer_alloc(list: TAsmList; size: longint);
      begin
        internalerror(200807237);
      end;


    procedure tcgarm.g_intf_wrapper(list: TAsmList; procdef: tprocdef; const labelname: string; ioffset: longint);

      procedure loadvmttor12;
        var
          href : treference;
        begin
          reference_reset_base(href,NR_R0,0);
          cg.a_load_ref_reg(list,OS_ADDR,OS_ADDR,href,NR_R12);
        end;


      procedure op_onr12methodaddr;
        var
          href : treference;
        begin
          if (procdef.extnumber=$ffff) then
            Internalerror(200006139);
          { call/jmp  vmtoffs(%eax) ; method offs }
          reference_reset_base(href,NR_R12,procdef._class.vmtmethodoffset(procdef.extnumber));
          cg.a_load_ref_reg(list,OS_ADDR,OS_ADDR,href,NR_R12);
          list.concat(taicpu.op_reg_reg(A_MOV,NR_PC,NR_R12));
        end;

      var
        make_global : boolean;
      begin
        if not(procdef.proctypeoption in [potype_function,potype_procedure]) then
          Internalerror(200006137);
        if not assigned(procdef._class) or
           (procdef.procoptions*[po_classmethod, po_staticmethod,
             po_methodpointer, po_interrupt, po_iocheck]<>[]) then
          Internalerror(200006138);
        if procdef.owner.symtabletype<>ObjectSymtable then
          Internalerror(200109191);

        make_global:=false;
        if (not current_module.is_unit) or
           create_smartlink or
           (procdef.owner.defowner.owner.symtabletype=globalsymtable) then
          make_global:=true;

        if make_global then
          list.concat(Tai_symbol.Createname_global(labelname,AT_FUNCTION,0))
        else
          list.concat(Tai_symbol.Createname(labelname,AT_FUNCTION,0));

        { the wrapper might need aktlocaldata for the additional data to
          load the constant }
        current_procinfo:=cprocinfo.create(nil);

        { set param1 interface to self  }
        g_adjust_self_value(list,procdef,ioffset);

        { case 4 }
        if po_virtualmethod in procdef.procoptions then
          begin
            loadvmttor12;
            op_onr12methodaddr;
          end
        { case 0 }
        else
          list.concat(taicpu.op_sym(A_B,current_asmdata.RefAsmSymbol(procdef.mangledname)));
        list.concatlist(current_procinfo.aktlocaldata);

        current_procinfo.Free;
        current_procinfo:=nil;

        list.concat(Tai_symbol_end.Createname(labelname));
      end;


    procedure tcgarm.maybeadjustresult(list: TAsmList; op: TOpCg; size: tcgsize; dst: tregister);
      const
        overflowops = [OP_MUL,OP_SHL,OP_ADD,OP_SUB,OP_NOT,OP_NEG];
      begin
        if (op in overflowops) and
           (size in [OS_8,OS_S8,OS_16,OS_S16]) then
          a_load_reg_reg(list,OS_32,size,dst,dst);
      end;


    procedure tcg64farm.a_op64_reg_reg(list : TAsmList;op:TOpCG;size : tcgsize;regsrc,regdst : tregister64);
      begin
        case op of
          OP_NEG:
            begin
              list.concat(setoppostfix(taicpu.op_reg_reg_const(A_RSB,regdst.reglo,regsrc.reglo,0),PF_S));
              list.concat(taicpu.op_reg_reg_const(A_RSC,regdst.reghi,regsrc.reghi,0));
            end;
          OP_NOT:
            begin
              cg.a_op_reg_reg(list,OP_NOT,OS_INT,regsrc.reglo,regdst.reglo);
              cg.a_op_reg_reg(list,OP_NOT,OS_INT,regsrc.reghi,regdst.reghi);
            end;
          else
            a_op64_reg_reg_reg(list,op,size,regsrc,regdst,regdst);
        end;
      end;


    procedure tcg64farm.a_op64_const_reg(list : TAsmList;op:TOpCG;size : tcgsize;value : int64;reg : tregister64);
      begin
        a_op64_const_reg_reg(list,op,size,value,reg,reg);
      end;


    procedure tcg64farm.a_op64_const_reg_reg(list: TAsmList;op:TOpCG;size : tcgsize;value : int64;regsrc,regdst : tregister64);
      var
        ovloc : tlocation;
      begin
        a_op64_const_reg_reg_checkoverflow(list,op,size,value,regsrc,regdst,false,ovloc);
      end;


    procedure tcg64farm.a_op64_reg_reg_reg(list: TAsmList;op:TOpCG;size : tcgsize;regsrc1,regsrc2,regdst : tregister64);
      var
        ovloc : tlocation;
      begin
        a_op64_reg_reg_reg_checkoverflow(list,op,size,regsrc1,regsrc2,regdst,false,ovloc);
      end;


    procedure tcg64farm.a_op64_const_reg_reg_checkoverflow(list: TAsmList;op:TOpCG;size : tcgsize;value : int64;regsrc,regdst : tregister64;setflags : boolean;var ovloc : tlocation);
      var
        tmpreg : tregister;
        b : byte;
      begin
        ovloc.loc:=LOC_VOID;
        case op of
          OP_NEG,
          OP_NOT :
            internalerror(200306017);
        end;
        if (setflags or tcgarm(cg).cgsetflags) and (op in [OP_ADD,OP_SUB]) then
          begin
            case op of
              OP_ADD:
                begin
                  if is_shifter_const(lo(value),b) then
                    list.concat(setoppostfix(taicpu.op_reg_reg_const(A_ADD,regdst.reglo,regsrc.reglo,lo(value)),PF_S))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,lo(value),tmpreg);
                      list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_ADD,regdst.reglo,regsrc.reglo,tmpreg),PF_S));
                    end;

                  if is_shifter_const(hi(value),b) then
                    list.concat(setoppostfix(taicpu.op_reg_reg_const(A_ADC,regdst.reghi,regsrc.reghi,hi(value)),PF_S))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,hi(value),tmpreg);
                      list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_ADC,regdst.reghi,regsrc.reghi,tmpreg),PF_S));
                    end;
                end;
              OP_SUB:
                begin
                  if is_shifter_const(lo(value),b) then
                    list.concat(setoppostfix(taicpu.op_reg_reg_const(A_SUB,regdst.reglo,regsrc.reglo,lo(value)),PF_S))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,lo(value),tmpreg);
                      list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_SUB,regdst.reglo,regsrc.reglo,tmpreg),PF_S));
                    end;

                  if is_shifter_const(hi(value),b) then
                    list.concat(setoppostfix(taicpu.op_reg_reg_const(A_SBC,regdst.reghi,regsrc.reghi,aint(hi(value))),PF_S))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,hi(value),tmpreg);
                      list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_SBC,regdst.reghi,regsrc.reghi,tmpreg),PF_S));
                    end;
                end;
              else
                internalerror(200502131);
            end;
            if size=OS_64 then
              begin
                { the arm has an weired opinion how flags for SUB/ADD are handled }
                ovloc.loc:=LOC_FLAGS;
                case op of
                  OP_ADD:
                    ovloc.resflags:=F_CS;
                  OP_SUB:
                    ovloc.resflags:=F_CC;
                end;
              end;
          end
        else
          begin
            case op of
              OP_AND,OP_OR,OP_XOR:
                begin
                  cg.a_op_const_reg_reg(list,op,OS_32,aint(lo(value)),regsrc.reglo,regdst.reglo);
                  cg.a_op_const_reg_reg(list,op,OS_32,aint(hi(value)),regsrc.reghi,regdst.reghi);
                end;
              OP_ADD:
                begin
                  if is_shifter_const(aint(lo(value)),b) then
                    list.concat(setoppostfix(taicpu.op_reg_reg_const(A_ADD,regdst.reglo,regsrc.reglo,aint(lo(value))),PF_S))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,aint(lo(value)),tmpreg);
                      list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_ADD,regdst.reglo,regsrc.reglo,tmpreg),PF_S));
                    end;

                  if is_shifter_const(aint(hi(value)),b) then
                    list.concat(taicpu.op_reg_reg_const(A_ADC,regdst.reghi,regsrc.reghi,aint(hi(value))))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,aint(hi(value)),tmpreg);
                      list.concat(taicpu.op_reg_reg_reg(A_ADC,regdst.reghi,regsrc.reghi,tmpreg));
                    end;
                end;
              OP_SUB:
                begin
                  if is_shifter_const(aint(lo(value)),b) then
                    list.concat(setoppostfix(taicpu.op_reg_reg_const(A_SUB,regdst.reglo,regsrc.reglo,aint(lo(value))),PF_S))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,aint(lo(value)),tmpreg);
                      list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_SUB,regdst.reglo,regsrc.reglo,tmpreg),PF_S));
                    end;

                  if is_shifter_const(aint(hi(value)),b) then
                    list.concat(taicpu.op_reg_reg_const(A_SBC,regdst.reghi,regsrc.reghi,aint(hi(value))))
                  else
                    begin
                      tmpreg:=cg.getintregister(list,OS_32);
                      cg.a_load_const_reg(list,OS_32,hi(value),tmpreg);
                      list.concat(taicpu.op_reg_reg_reg(A_SBC,regdst.reghi,regsrc.reghi,tmpreg));
                    end;
                end;
            else
              internalerror(2003083101);
          end;
        end;
      end;


    procedure tcg64farm.a_op64_reg_reg_reg_checkoverflow(list: TAsmList;op:TOpCG;size : tcgsize;regsrc1,regsrc2,regdst : tregister64;setflags : boolean;var ovloc : tlocation);
      begin
        ovloc.loc:=LOC_VOID;
        case op of
          OP_NEG,
          OP_NOT :
            internalerror(200306017);
        end;
        if (setflags or tcgarm(cg).cgsetflags) and (op in [OP_ADD,OP_SUB]) then
          begin
            case op of
              OP_ADD:
                begin
                  list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_ADD,regdst.reglo,regsrc1.reglo,regsrc2.reglo),PF_S));
                  list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_ADC,regdst.reghi,regsrc1.reghi,regsrc2.reghi),PF_S));
                end;
              OP_SUB:
                begin
                  list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_SUB,regdst.reglo,regsrc2.reglo,regsrc1.reglo),PF_S));
                  list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_SBC,regdst.reghi,regsrc2.reghi,regsrc1.reghi),PF_S));
                end;
              else
                internalerror(2003083101);
            end;
            if size=OS_64 then
              begin
                { the arm has an weired opinion how flags for SUB/ADD are handled }
                ovloc.loc:=LOC_FLAGS;
                case op of
                  OP_ADD:
                    ovloc.resflags:=F_CS;
                  OP_SUB:
                    ovloc.resflags:=F_CC;
                end;
              end;
          end
        else
          begin
            case op of
              OP_AND,OP_OR,OP_XOR:
                begin
                  cg.a_op_reg_reg_reg(list,op,OS_32,regsrc1.reglo,regsrc2.reglo,regdst.reglo);
                  cg.a_op_reg_reg_reg(list,op,OS_32,regsrc1.reghi,regsrc2.reghi,regdst.reghi);
                end;
              OP_ADD:
                begin
                  list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_ADD,regdst.reglo,regsrc1.reglo,regsrc2.reglo),PF_S));
                  list.concat(taicpu.op_reg_reg_reg(A_ADC,regdst.reghi,regsrc1.reghi,regsrc2.reghi));
                end;
              OP_SUB:
                begin
                  list.concat(setoppostfix(taicpu.op_reg_reg_reg(A_SUB,regdst.reglo,regsrc2.reglo,regsrc1.reglo),PF_S));
                  list.concat(taicpu.op_reg_reg_reg(A_SBC,regdst.reghi,regsrc2.reghi,regsrc1.reghi));
                end;
              else
                internalerror(2003083101);
            end;
          end;
      end;


begin
  cg:=tcgarm.create;
  cg64:=tcg64farm.create;
end.