freepascal.compiler/compiler/riscv/cgrv.pas

{
    Copyright (c) 2006 by Florian Klaempfl

    This unit implements the common part of the code generator for the Risc-V

    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 cgrv;

{$i fpcdefs.inc}
  interface

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

    type
      tcgrv = class(tcg)
        procedure a_loadaddr_ref_cgpara(list : TAsmList;const r : treference;const paraloc : tcgpara); override;

        procedure a_bit_scan_reg_reg(list: TAsmList; reverse: boolean; srcsize, dstsize: tcgsize; src, dst: TRegister); override;

        procedure a_call_reg(list : TAsmList;reg: tregister); override;
        procedure a_call_name(list : TAsmList;const s : string; weak: boolean); override;

        procedure a_load_const_ref(list: TAsmList; size: tcgsize; a: tcgint; const ref: treference); 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_const_reg(list: TAsmList; size: tcgsize; a: tcgint; register: tregister); override;            

        procedure a_op_const_reg(list : TAsmList; Op: TOpCG; size: TCGSize; a: tcgint; 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: tcgint; src, dst: tregister); override;
        procedure a_op_reg_reg_reg(list: TAsmList; op: TOpCg; size: tcgsize; src1, src2, dst: tregister); override;

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

        procedure a_cmp_const_reg_label(list : TAsmList;size : tcgsize;cmp_op : topcmp;a : tcgint;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 g_proc_entry(list : TAsmList;localsize : longint;nostackframe:boolean);override;
        procedure g_proc_exit(list : TAsmList;parasize : longint;nostackframe:boolean); override;

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

        procedure g_profilecode(list: TAsmList); override;

        { 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 g_check_for_fpu_exception(list: TAsmList;force,clear : boolean); override;
      protected
        function  fixref(list: TAsmList; var ref: treference): boolean;
        procedure maybeadjustresult(list: TAsmList; op: topcg; size: tcgsize; dst: tregister);
      end;

  const
    TOpCmp2AsmCond: Array[topcmp] of TAsmCond = (C_NONE,C_EQ,C_NONE,
                         C_LT,C_GE,C_None,C_NE,C_NONE,C_LTU,C_GEU,C_NONE);

  const
    TOpCG2AsmConstOp: Array[topcg] of TAsmOp = (A_NONE,
          A_NONE,A_ADDI,A_ANDI,A_NONE,A_NONE,A_NONE,A_NONE,
          A_None,A_None,A_ORI,A_SRAI,A_SLLI,A_SRLI,A_NONE,A_XORI,A_None,A_None);
    TOpCG2AsmOp: Array[topcg] of TAsmOp = (A_NONE,
          A_NONE,A_ADD,A_AND,A_DIVU,A_DIV,A_MUL,A_MUL,
          A_None,A_None,A_OR,A_SRA,A_SLL,A_SRL,A_SUB,A_XOR,A_None,A_None);

{$ifdef extdebug}
     function ref2string(const ref : treference) : string;
     function cgop2string(const op : TOpCg) : String;
{$endif extdebug}

  implementation

    uses
       {$ifdef extdebug}sysutils,{$endif}
       globals,verbose,systems,cutils,
       symconst,symsym,symtable,fmodule,
       rgobj,tgobj,cpupi,procinfo,paramgr;

{$ifdef extdebug}
     function ref2string(const ref : treference) : string;
       begin
         result := 'base : ' + inttostr(ord(ref.base)) + ' index : ' + inttostr(ord(ref.index)) + ' refaddr : ' + inttostr(ord(ref.refaddr)) + ' offset : ' + inttostr(ref.offset) + ' symbol : ';
         if (assigned(ref.symbol)) then
           result := result + ref.symbol.name;
       end;

     function cgop2string(const op : TOpCg) : String;
       const
         opcg_strings : array[TOpCg] of string[6] = (
           'None', 'Move', 'Add', 'And', 'Div', 'IDiv', 'IMul', 'Mul',
           'Neg', 'Not', 'Or', 'Sar', 'Shl', 'Shr', 'Sub', 'Xor', 'Rol', 'Ror'
         );
       begin
         result := opcg_strings[op];
       end;
{$endif extdebug}


    procedure tcgrv.a_call_name(list : TAsmList;const s : string; weak: boolean);
      var
        href: treference;
        l: TAsmLabel;
      begin
        if not(weak) then
          reference_reset_symbol(href,current_asmdata.RefAsmSymbol(s,AT_FUNCTION),0,0,[])
        else
          reference_reset_symbol(href,current_asmdata.WeakRefAsmSymbol(s,AT_FUNCTION),0,0,[]);

        if cs_create_pic in current_settings.moduleswitches then
          begin
            href.refaddr:=addr_plt;
            list.concat(taicpu.op_ref(A_CALL,href));
          end
        else
          begin
            current_asmdata.getjumplabel(l);

            a_label(list,l);

            href.refaddr:=addr_pcrel_hi20;
            list.concat(taicpu.op_reg_ref(A_AUIPC,NR_RETURN_ADDRESS_REG,href));

            reference_reset_symbol(href,l,0,0,[]);
            href.refaddr:=addr_pcrel_lo12;
            list.concat(taicpu.op_reg_reg_ref(A_JALR,NR_RETURN_ADDRESS_REG,NR_RETURN_ADDRESS_REG,href));
          end;

        { not assigned while generating external wrappers }
        if assigned(current_procinfo) then
          include(current_procinfo.flags,pi_do_call);
      end;


    procedure tcgrv.a_load_const_ref(list: TAsmList; size: tcgsize; a: tcgint; const ref: treference);
      begin
        if a=0 then
          a_load_reg_ref(list,size,size,NR_X0,ref)
        else
          inherited a_load_const_ref(list, size, a, ref);
      end;


    procedure tcgrv.a_loadaddr_ref_cgpara(list : TAsmList;const r : treference;const paraloc : tcgpara);
      var
        ref: treference;
        tmpreg: tregister;

      begin
        paraloc.check_simple_location;
        paramanager.allocparaloc(list,paraloc.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,paraloc.alignment,[]);
               ref.base := paraloc.location^.reference.index;
               ref.offset := paraloc.location^.reference.offset;
               tmpreg := rg[R_INTREGISTER].getregister(list,R_SUBWHOLE);
               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 tcgrv.a_bit_scan_reg_reg(list: TAsmList; reverse: boolean; srcsize, dstsize: tcgsize; src, dst: TRegister);
      begin
        internalerror(2016060401);
      end;       


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


    procedure tcgrv.a_op_reg_reg(list : TAsmList; Op: TOpCG; size: TCGSize; src, dst: TRegister);
      begin
        a_op_reg_reg_reg(list,op,size,src,dst,dst);
      end;


    procedure tcgrv.a_op_const_reg_reg(list: TAsmList; op: TOpCg; size: tcgsize; a: tcgint; src, dst: tregister);
      var
        tmpreg: TRegister;
      begin
        optimize_op_const(size,op,a);

        if op=OP_NONE then
          begin
            a_load_reg_reg(list,size,size,src,dst);
            exit;
          end;

        if op=OP_SUB then
          begin
            op:=OP_ADD;
            a:=-a;
          end;

{$ifdef RISCV64}
        if (op=OP_SHL) and
               (size=OS_S32) then
          begin
            list.concat(taicpu.op_reg_reg_const(A_SLLIW,dst,src,a));
            maybeadjustresult(list,op,size,dst);
          end
        else if (op=OP_SHR) and
               (size=OS_S32) then
          begin
            list.concat(taicpu.op_reg_reg_const(A_SRLIW,dst,src,a));
            maybeadjustresult(list,op,size,dst);
          end
        else if (op=OP_SAR) and
               (size=OS_S32) then
          begin
            list.concat(taicpu.op_reg_reg_const(A_SRAIW,dst,src,a));
            maybeadjustresult(list,op,size,dst);
          end
        else
{$endif RISCV64}
        if (TOpCG2AsmConstOp[op]<>A_None) and
           is_imm12(a) then
          begin
            list.concat(taicpu.op_reg_reg_const(TOpCG2AsmConstOp[op],dst,src,a));
            maybeadjustresult(list,op,size,dst);
          end
        else
          begin
            tmpreg:=getintregister(list,size);
            a_load_const_reg(list,size,a,tmpreg);
            a_op_reg_reg_reg(list,op,size,tmpreg,src,dst);
          end;
      end;   


    procedure tcgrv.a_op_reg_reg_reg(list: TAsmList; op: TOpCg; size: tcgsize; src1, src2, dst: tregister);
      var
        name: String;
        pd: tprocdef;
        paraloc1, paraloc2: tcgpara;
      begin
        if op=OP_NOT then
          begin
            list.concat(taicpu.op_reg_reg_const(A_XORI,dst,src1,-1));
            maybeadjustresult(list,op,size,dst);
          end
        else if op=OP_NEG then
          begin
            list.concat(taicpu.op_reg_reg_reg(A_SUB,dst,NR_X0,src1));
            maybeadjustresult(list,op,size,dst);
          end
        else
          case op of
            OP_MOVE:
              a_load_reg_reg(list,size,size,src1,dst);
          else
{$ifdef RISCV64}
            if (op=OP_SHL) and
               (size=OS_S32) then
              begin
                list.concat(taicpu.op_reg_reg_reg(A_SLLW,dst,src2,src1));
                maybeadjustresult(list,op,size,dst);
              end
            else if (op=OP_SHR) and
               (size=OS_S32) then
              begin
                list.concat(taicpu.op_reg_reg_reg(A_SRLW,dst,src2,src1));
                maybeadjustresult(list,op,size,dst);
              end
            else if (op=OP_SAR) and
               (size=OS_S32) then
              begin
                list.concat(taicpu.op_reg_reg_reg(A_SRAW,dst,src2,src1));
                maybeadjustresult(list,op,size,dst);
              end
            else if (op=OP_SUB) and
               (size in [OS_32,OS_S32]) then
              begin
                list.concat(taicpu.op_reg_reg_reg(A_SUBW,dst,src2,src1));
                maybeadjustresult(list,op,size,dst);
              end
            else
{$endif RISCV64}
            if (op in [OP_IMUL,OP_MUL]) and not(CPURV_HAS_MUL in cpu_capabilities[current_settings.cputype]) then
              begin
                case size of
                  OS_8:
                    name:='fpc_mul_byte';
                  OS_S8:
                    name:='fpc_mul_shortint';
                  OS_16:
                    name:='fpc_mul_word';
                  OS_S16:
                    name:='fpc_mul_integer';
                  OS_32:
                    name:='fpc_mul_dword';
                  OS_S32:
                    name:='fpc_mul_longint';
                  else
                    Internalerror(2021030601);
                end;

//                if check_overflow then
//                  name:=name+'_checkoverflow';

                pd:=search_system_proc(name);
                paraloc1.init;
                paraloc2.init;
                paramanager.getcgtempparaloc(list,pd,1,paraloc1);
                paramanager.getcgtempparaloc(list,pd,2,paraloc2);
                a_load_reg_cgpara(list,OS_8,src1,paraloc2);
                a_load_reg_cgpara(list,OS_8,src2,paraloc1);
                paramanager.freecgpara(list,paraloc2);
                paramanager.freecgpara(list,paraloc1);
                alloccpuregisters(list,R_INTREGISTER,paramanager.get_volatile_registers_int(pocall_default));
                a_call_name(list,upper(name),false);
                dealloccpuregisters(list,R_INTREGISTER,paramanager.get_volatile_registers_int(pocall_default));
                cg.a_reg_alloc(list,NR_FUNCTION_RESULT_REG);
                cg.a_load_reg_reg(list,size,size,NR_FUNCTION_RESULT_REG,dst);
                cg.a_reg_dealloc(list,NR_FUNCTION_RESULT_REG);
                paraloc2.done;
                paraloc1.done;
              end
            else
              begin
                list.concat(taicpu.op_reg_reg_reg(TOpCG2AsmOp[op],dst,src2,src1));
                maybeadjustresult(list,op,size,dst);
              end;
          end;
      end;


    procedure tcgrv.a_loadaddr_ref_reg(list : TAsmList;const ref : treference;r : tregister);
      var
        href: treference;
        b, tmpreg: TRegister;
        l: TAsmLabel;
      begin
        href:=ref;
        fixref(list,href);

        if (not assigned(href.symbol)) and
           (href.offset=0) then
          a_load_reg_reg(list,OS_ADDR,OS_ADDR,href.base,r)
        else if (assigned(href.symbol) or
            (not is_imm12(href.offset))) and
           (href.base<>NR_NO) then
          begin
            b:= href.base;

            current_asmdata.getjumplabel(l);
            a_label(list,l);

            href.base:=NR_NO;
            href.refaddr:=addr_pcrel_hi20;
            list.concat(taicpu.op_reg_ref(A_AUIPC,r,href));

            reference_reset_symbol(href,l,0,0,ref.volatility);
            href.refaddr:=addr_pcrel_lo12;
            list.concat(taicpu.op_reg_reg_ref(A_ADDI,r,r,href));

            list.concat(taicpu.op_reg_reg_reg(A_ADD,r,r,b));
          end
        else if is_imm12(href.offset) and
           (href.base<>NR_NO) then
          begin
            list.concat(taicpu.op_reg_reg_const(A_ADDI,r,href.base,href.offset));
          end
        else if (href.refaddr=addr_pcrel) then
          begin                     
            tmpreg:=getintregister(list,OS_ADDR);

            b:=href.base;
            href.base:=NR_NO;
                                        
            current_asmdata.getjumplabel(l);
            a_label(list,l);

            href.refaddr:=addr_pcrel_hi20;
            list.concat(taicpu.op_reg_ref(A_AUIPC,tmpreg,href));

            reference_reset_symbol(href,l,0,0,ref.volatility);
            href.refaddr:=addr_pcrel_lo12;
            list.concat(taicpu.op_reg_reg_ref(A_ADDI,r,tmpreg,href));

            if b<>NR_NO then
              list.concat(taicpu.op_reg_reg_reg(A_ADD,r,r,b));
          end
        else
          internalerror(2016060504);
      end;                


    procedure tcgrv.a_cmp_const_reg_label(list: TAsmList; size: tcgsize; cmp_op: topcmp; a: tcgint; reg: tregister; l: tasmlabel);
      begin
        if a=0 then
          a_cmp_reg_reg_label(list,size,cmp_op,NR_X0,reg,l)
        else
          inherited;
      end;


    procedure tcgrv.a_cmp_reg_reg_label(list : TAsmList;size : tcgsize;cmp_op : topcmp; reg1,reg2 : tregister;l : tasmlabel);
      var
        tmpreg: TRegister;
        ai: taicpu;
      begin
        if TOpCmp2AsmCond[cmp_op]=C_None then
          begin
            cmp_op:=swap_opcmp(cmp_op);
            tmpreg:=reg1;
            reg1:=reg2;
            reg2:=tmpreg;
          end;

        ai:=taicpu.op_reg_reg_sym_ofs(A_Bxx,reg2,reg1,l,0);
        ai.is_jmp:=true;
        ai.condition:=TOpCmp2AsmCond[cmp_op];
        list.concat(ai);
      end;


    procedure tcgrv.a_jmp_name(list : TAsmList;const s : string);
      var
        ai: taicpu;
        href: treference;
        tmpreg: TRegister;
        l: TAsmLabel;
      begin
        reference_reset_symbol(href,current_asmdata.RefAsmSymbol(s,AT_FUNCTION),0,0,[]);

        tmpreg:=getintregister(list,OS_ADDR);

        current_asmdata.getjumplabel(l);
        a_label(list,l);

        href.refaddr:=addr_pcrel_hi20;
        list.concat(taicpu.op_reg_ref(A_AUIPC,tmpreg,href));
        reference_reset_symbol(href,l,0,0,[]);
        href.refaddr:=addr_pcrel_lo12;
        ai:=taicpu.op_reg_reg_ref(A_JALR,NR_X0,tmpreg,href);
        ai.is_jmp:=true;
        list.concat(ai);

        //ai:=taicpu.op_reg_sym(A_JAL,NR_X0,current_asmdata.RefAsmSymbol(s));
        //ai.is_jmp:=true;
      end;


    procedure tcgrv.a_jmp_always(list : TAsmList;l: tasmlabel);
      var
        ai: taicpu;
        {href: treference;
        tmpreg: TRegister;}
      begin
        {reference_reset_symbol(href,l,0,0);

        tmpreg:=getintregister(list,OS_ADDR);    

        current_asmdata.getjumplabel(l);
        a_label(list,l);

        href.refaddr:=addr_pcrel_hi20;
        list.concat(taicpu.op_reg_ref(A_AUIPC,tmpreg,href));
        reference_reset_symbol(href,l,0,0);
        href.refaddr:=addr_pcrel_lo12;
        ai:=taicpu.op_reg_reg_ref(A_JALR,NR_X0,tmpreg,href);
        ai.is_jmp:=true;
        list.concat(ai);}

        ai:=taicpu.op_reg_sym(A_JAL,NR_X0,l);
        ai.is_jmp:=true;
        list.concat(ai);
       end;


    procedure tcgrv.g_proc_entry(list: TAsmList; localsize: longint; nostackframe: boolean);
      const
{$ifdef cpu64bitalu}
        store_int_op = A_SD;
{$else  cpu64bitalu}
        store_int_op = A_SW;
{$endif cpu64bitalu}
      var
        regs, fregs: tcpuregisterset;
        r: TSuperRegister;
        href: treference;
        stackcount, stackAdjust: longint;
      begin
        if not(nostackframe) then
          begin
            a_reg_alloc(list,NR_STACK_POINTER_REG);
            if current_procinfo.framepointer<>NR_STACK_POINTER_REG then
              a_reg_alloc(list,NR_FRAME_POINTER_REG);

            { Int registers }
            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_FRAME_POINTER_REG,RS_RETURN_ADDRESS_REG];

            if (pi_do_call in current_procinfo.flags) then
              regs:=regs+[RS_RETURN_ADDRESS_REG];

            stackcount:=0;
            for r:=RS_X0 to RS_X31 do
              if r in regs then
                inc(stackcount,sizeof(pint));

            { Float registers }
            fregs:=rg[R_FPUREGISTER].used_in_proc-paramanager.get_volatile_registers_fpu(pocall_stdcall);
            for r:=RS_F0 to RS_F31 do
              if r in fregs then
                inc(stackcount,8);

            inc(localsize,stackcount);
            if not is_imm12(-localsize) then
              begin
                if not (RS_RETURN_ADDRESS_REG in regs) then
                  begin
                    include(regs,RS_RETURN_ADDRESS_REG);
                    inc(localsize,sizeof(pint));
                  end;
              end;
               
            reference_reset_base(href,NR_STACK_POINTER_REG,stackcount,ctempposinvalid,0,[]);

            stackAdjust:=0;
            if stackcount>0 then
              begin
                list.concat(taicpu.op_reg_reg_const(A_ADDI,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,-stackcount));
                stackAdjust:=stackcount;
                dec(localsize,stackcount);
              end;

            for r:=RS_X0 to RS_X31 do
              if r in regs then
                begin
                  dec(href.offset,sizeof(pint));
                  list.concat(taicpu.op_reg_ref(store_int_op,newreg(R_INTREGISTER,r,R_SUBWHOLE),href));
                end;

            { Float registers }
            for r:=RS_F0 to RS_F31 do
              if r in fregs then
                begin
                  dec(href.offset,8);
                  list.concat(taicpu.op_reg_ref(A_FSD,newreg(R_FPUREGISTER,r,R_SUBWHOLE),href));
                end;

            if current_procinfo.framepointer<>NR_STACK_POINTER_REG then
              list.concat(taicpu.op_reg_reg_const(A_ADDI,NR_FRAME_POINTER_REG,NR_STACK_POINTER_REG,stackAdjust));

            if localsize>0 then
              begin
                localsize:=align(localsize,sizeof(pint));

                if is_imm12(-localsize) then
                  list.concat(taicpu.op_reg_reg_const(A_ADDI,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,-localsize))
                else
                  begin
                    a_load_const_reg(list,OS_INT,localsize,NR_RETURN_ADDRESS_REG);
                    list.concat(taicpu.op_reg_reg_reg(A_SUB,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,NR_RETURN_ADDRESS_REG));
                  end;
              end;
          end;
      end;


    procedure tcgrv.g_proc_exit(list: TAsmList; parasize: longint; nostackframe: boolean);
      const
{$ifdef cpu64bitalu}
        load_op = A_LD;
{$else  cpu64bitalu}
        load_op = A_LW;
{$endif cpu64bitalu}
      var
        r: tsuperregister;
        regs, fregs: tcpuregisterset;
        stacksize, localsize, precompensation, postcompensation: longint;
        href: treference;
      begin
        if not(nostackframe) then
          begin
            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_FRAME_POINTER_REG,RS_RETURN_ADDRESS_REG];

            if (pi_do_call in current_procinfo.flags) then
              regs:=regs+[RS_RETURN_ADDRESS_REG];

            stacksize:=0;
            for r:=RS_X31 downto RS_X0 do
              if r in regs then
                inc(stacksize,sizeof(pint));

            { Float registers }
            fregs:=rg[R_FPUREGISTER].used_in_proc-paramanager.get_volatile_registers_fpu(pocall_stdcall);
            for r:=RS_F0 to RS_F31 do
              if r in fregs then
                inc(stacksize,8);

            localsize:=current_procinfo.calc_stackframe_size+stacksize;
            if localsize>0 then
              begin
                localsize:=align(localsize,sizeof(pint));

                if not is_imm12(-localsize) then
                  begin
                    if not (RS_RETURN_ADDRESS_REG in regs) then
                      begin
                        include(regs,RS_RETURN_ADDRESS_REG);
                        inc(localsize,sizeof(pint));
                        inc(stacksize,sizeof(pint));
                      end;
                  end;
              end;

            if not is_imm12(localsize) then
              begin
                precompensation:=localsize-2032;
                postcompensation:=localsize-precompensation;
              end
            else
              begin            
                precompensation:=0;
                postcompensation:=localsize;
              end;
            
            reference_reset_base(href,NR_STACK_POINTER_REG,postcompensation-stacksize,ctempposinvalid,0,[]);

            if precompensation>0 then
              begin
                if is_imm12(precompensation) then
                  list.concat(taicpu.op_reg_reg_const(A_ADDI,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,precompensation))
                else
                  begin
                    { use X12 as temporary register as it is not callee-saved }
                    a_load_const_reg(list,OS_INT,precompensation,NR_X12);
                    list.concat(taicpu.op_reg_reg_reg(A_ADD,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,NR_X12));
                  end;
              end;

            { Float registers }
            for r:=RS_F31 downto RS_F0 do
              if r in fregs then
                begin
                  list.concat(taicpu.op_reg_ref(A_FLD,newreg(R_FPUREGISTER,r,R_SUBWHOLE),href));
                  inc(href.offset,8);
                end;

            for r:=RS_X31 downto RS_X0 do
              if r in regs then
                begin
                  list.concat(taicpu.op_reg_ref(load_op,newreg(R_INTREGISTER,r,R_SUBWHOLE),href));
                  inc(href.offset,sizeof(pint));
                end;

            if postcompensation>0 then
              list.concat(taicpu.op_reg_reg_const(A_ADDI,NR_STACK_POINTER_REG,NR_STACK_POINTER_REG,postcompensation));
          end;

        if (target_info.system in (systems_freertos+systems_embedded)) and (po_interrupt in current_procinfo.procdef.procoptions) then
          begin
            list.concat(Taicpu.Op_none(A_MRET));
          end
        else
          list.concat(taicpu.op_reg_reg(A_JALR,NR_X0,NR_RETURN_ADDRESS_REG));
      end;


    procedure tcgrv.g_save_registers(list: TAsmList);
      begin
      end;


    procedure tcgrv.g_restore_registers(list: TAsmList);
      begin
      end;


    procedure tcgrv.g_profilecode(list: TAsmList);
      begin
        if target_info.system in [system_riscv32_linux,system_riscv64_linux] then
          begin
            list.concat(taicpu.op_reg_reg_const(A_ADDI,NR_X10,NR_RETURN_ADDRESS_REG,0));
            a_call_name(list,'_mcount',false);
          end
        else
          internalerror(2018092201);
      end;


    procedure tcgrv.a_call_reg(list : TAsmList;reg: tregister);
      begin
        list.concat(taicpu.op_reg_reg(A_JALR,NR_RETURN_ADDRESS_REG,reg));
        include(current_procinfo.flags,pi_do_call);
      end;


    procedure tcgrv.a_load_reg_ref(list: TAsmList; fromsize, tosize: TCGSize;
        reg: tregister; const ref: treference);

      const
        StoreInstr: array[OS_8..OS_INT] of TAsmOp =
        (A_SB,A_SH,A_SW
{$ifdef cpu64bitalu}
         ,
         A_SD
{$endif cpu64bitalu}
         );
      var
        ref2: TReference;
        tmpreg: tregister;
        op: TAsmOp;
      begin
        if not (fromsize in [OS_8..OS_INT,OS_S8..OS_SINT]) then
          internalerror(2002090904);
        if not (tosize in [OS_8..OS_INT,OS_S8..OS_SINT]) then
          internalerror(2002090905);

        tosize:=tcgsize2unsigned[tosize];

        ref2 := ref;
        fixref(list, ref2);

        op := storeinstr[tcgsize2unsigned[tosize]];
        list.concat(taicpu.op_reg_ref(op, reg,ref2));
      end;


    procedure tcgrv.a_load_ref_reg(list: TAsmList; fromsize, tosize: tcgsize; const ref: treference; reg: tregister);
      var
        href: treference;
        op: TAsmOp;
        tmpreg: TRegister;
      begin
        href:=ref;
        fixref(list,href);

        if href.refaddr=addr_pcrel then
          begin
            tmpreg:=getintregister(list,OS_ADDR);
            a_loadaddr_ref_reg(list,href,tmpreg);
            reference_reset_base(href,tmpreg,0,ctempposinvalid,0,ref.volatility);
          end;

        case fromsize of
          OS_8: op:=A_LBU;
          OS_16: op:=A_LHU;
          OS_S8: op:=A_LB;
          OS_S16: op:=A_LH;
{$ifdef RISCV64}
          OS_32: op:=A_LWU;
          OS_S32: op:=A_LW;
          OS_64,
          OS_S64: op:=A_LD;
{$else}
          OS_64,OS_S64, { This only happens if tosize is smaller than fromsize }
          { We can therefore only consider the low 32-bit of the 64bit value }
          OS_32,
          OS_S32: op:=A_LW;
{$endif}
        else
          internalerror(2016060502);
        end;

        list.concat(taicpu.op_reg_ref(op,reg,href));
        if (fromsize<>tosize) and (not (tosize in [OS_SINT,OS_INT])) then
          a_load_reg_reg(list,fromsize,tosize,reg,reg);
      end;


    procedure tcgrv.a_load_const_reg(list: TAsmList; size: tcgsize; a: tcgint; register: tregister);
      begin
        if a=0 then
          a_load_reg_reg(list,size,size,NR_X0,register)
        else
          begin
            if is_imm12(a) then
              list.concat(taicpu.op_reg_reg_const(A_ADDI,register,NR_X0,a))
            else if is_lui_imm(a) then
              list.concat(taicpu.op_reg_const(A_LUI,register,(a shr 12) and $FFFFF))
            else
              begin
                if (a and $800)<>0 then
                  list.concat(taicpu.op_reg_const(A_LUI,register,((a shr 12)+1) and $FFFFF))
                else
                  list.concat(taicpu.op_reg_const(A_LUI,register,(a shr 12) and $FFFFF));

                list.concat(taicpu.op_reg_reg_const(A_ADDI,register,register,SarSmallint(smallint(a shl 4),4)));
              end;
          end;
      end;


    procedure tcgrv.a_loadfpu_reg_reg(list: TAsmList; fromsize, tosize: tcgsize; reg1, reg2: tregister);
      var
        op: TAsmOp;
        ai: taicpu;

      const
        convOp: array[OS_F32..OS_F64,OS_F32..OS_F64] of TAsmOp =
        ((A_None,A_FCVT_D_S),
         (A_FCVT_S_D,A_None));

      begin
        if fromsize<>tosize then
          begin
            list.concat(taicpu.op_reg_reg(convOp[fromsize,tosize],reg2,reg1));
            maybe_check_for_fpu_exception(list);
          end
        else
          begin
            if tosize=OS_F32 then
              op:=A_FSGNJ_S
            else
              op:=A_FSGNJ_D;

            ai:=taicpu.op_reg_reg_reg(op,reg2,reg1,reg1);
            list.concat(ai);
            rg[R_FPUREGISTER].add_move_instruction(ai);
          end;
      end;


    procedure tcgrv.a_loadfpu_ref_reg(list: TAsmList; fromsize, tosize: tcgsize; const ref: treference; reg: tregister);
      var
        href: treference;
        op: TAsmOp;
        tmpreg: TRegister;
        l: TAsmLabel;
      begin
        href:=ref;
        fixref(list,href);      

        if href.refaddr=addr_pcrel then
          begin
            tmpreg:=getintregister(list,OS_ADDR);
            a_loadaddr_ref_reg(list,href,tmpreg);
            reference_reset_base(href,tmpreg,0,ctempposinvalid,0,ref.volatility);
          end;

        if fromsize=OS_F32 then
          op:=A_FLW
        else
          op:=A_FLD;

        list.concat(taicpu.op_reg_ref(op,reg,href));

        if fromsize<>tosize then
          a_loadfpu_reg_reg(list,fromsize,tosize,reg,reg);
      end;


    procedure tcgrv.a_loadfpu_reg_ref(list: TAsmList; fromsize, tosize: tcgsize; reg: tregister; const ref: treference);
      var
        href: treference;
        op: TAsmOp;
        tmpreg: TRegister;
      begin
        href:=ref;
        fixref(list,href);    

        if href.refaddr=addr_pcrel then
          begin
            tmpreg:=getintregister(list,OS_ADDR);
            a_loadaddr_ref_reg(list,href,tmpreg);
            reference_reset_base(href,tmpreg,0,ctempposinvalid,0,ref.volatility);
          end;

        if fromsize<>tosize then
          begin
            tmpreg:=getfpuregister(list,tosize);
            a_loadfpu_reg_reg(list,fromsize,tosize,reg,tmpreg);
            reg:=tmpreg;
          end;

        if tosize=OS_F32 then
          op:=A_FSW
        else
          op:=A_FSD;

        list.concat(taicpu.op_reg_ref(op,reg,href));
      end;


    function tcgrv.fixref(list: TAsmList; var ref: treference): boolean;
      var
        tmpreg: TRegister;
        href: treference;
        l: TAsmLabel;
      begin
        result:=true;

        if ref.refaddr=addr_pcrel then
          exit;

        if assigned(ref.symbol) then
          begin
{$ifdef unsed}
            { keeping the code for reference

              we use the pseudo instruction LA below which is expanded by the assembler, doing
              so results in more readable assembler and easier optimization of the assembler code
            }
            if cs_create_pic in current_settings.moduleswitches then
              begin
                reference_reset_symbol(href,ref.symbol,0,0,[]);
                ref.symbol:=nil;

                tmpreg:=getintregister(list,OS_INT);

                current_asmdata.getaddrlabel(l);
                a_label(list,l);

                href.refaddr:=addr_got_pcrel_hi;
                list.concat(taicpu.op_reg_ref(A_AUIPC,tmpreg,href));
                reference_reset_symbol(href,l,0,0,[]);
                href.refaddr:=addr_pcrel_lo12;
                href.base:=tmpreg;
{$ifdef RISCV64}
                list.concat(taicpu.op_reg_ref(A_LD,tmpreg,href));
{$else}
                list.concat(taicpu.op_reg_ref(A_LW,tmpreg,href));
{$endif}
              end
            else
              begin
                reference_reset_symbol(href,ref.symbol,ref.offset,ref.alignment,ref.volatility);
                ref.symbol:=nil;
                ref.offset:=0;

                tmpreg:=getintregister(list,OS_INT);

                current_asmdata.getaddrlabel(l);
                a_label(list,l);

                href.refaddr:=addr_pcrel_hi20;
                list.concat(taicpu.op_reg_ref(A_AUIPC,tmpreg,href));
                reference_reset_symbol(href,l,0,0,ref.volatility);
                href.refaddr:=addr_pcrel_lo12;
                list.concat(taicpu.op_reg_reg_ref(A_ADDI,tmpreg,tmpreg,href));
              end;
{$endif unsed}

            reference_reset_symbol(href,ref.symbol,0,0,[]);
            href.refaddr:=addr_full;
            ref.symbol:=nil;

            tmpreg:=getintregister(list,OS_ADDR);

            list.concat(taicpu.op_reg_ref(A_LA,tmpreg,href));

            if (ref.index<>NR_NO) and
               (ref.base<>NR_NO) then
              begin
                a_op_reg_reg(list,OP_ADD,OS_INT,ref.base,tmpreg);
                ref.base:=tmpreg;
              end
            else if (ref.index=NR_NO) and
               (ref.base<>NR_NO) then
              ref.index:=tmpreg
            else
              ref.base:=tmpreg;
          end
        else if (ref.index=NR_NO) and
                (ref.base=NR_NO) then
          begin              
            tmpreg:=getintregister(list,OS_INT);

            a_load_const_reg(list, OS_ADDR,ref.offset,tmpreg);

            reference_reset_base(ref,tmpreg,0,ctempposinvalid,ref.alignment,ref.volatility);
          end;

        if (ref.index<>NR_NO) and
           (ref.base=NR_NO) then
          begin
            ref.base:=ref.index;
            ref.index:=NR_NO;
          end;

        if not is_imm12(ref.offset) then
          begin
            tmpreg:=getintregister(list,OS_INT);
            a_load_const_reg(list,OS_INT,ref.offset,tmpreg);

            ref.offset:=0;

            if (ref.index<>NR_NO) and
               (ref.base<>NR_NO) then
              begin
                a_op_reg_reg(list,OP_ADD,OS_INT,ref.index,tmpreg);
                ref.index:=tmpreg;
              end
            else
              ref.index:=tmpreg;
          end;

        if (ref.index<>NR_NO) and
           (ref.base<>NR_NO) then
          begin
            tmpreg:=getaddressregister(list);
            list.concat(taicpu.op_reg_reg_reg(A_ADD,tmpreg,ref.base,ref.index));
            ref.base:=tmpreg;
            ref.index:=NR_NO;
          end;
      end;


    procedure tcgrv.maybeadjustresult(list: TAsmList; op: topcg; size: tcgsize; dst: tregister);
      const
        overflowops = [OP_MUL,OP_IMUL,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{$ifdef RISCV64},OS_32,OS_S32{$endif RISCV64}]) then
          a_load_reg_reg(list,OS_INT,size,dst,dst)
      end;


    procedure tcgrv.g_check_for_fpu_exception(list: TAsmList;force,clear : boolean);
      var
        r : TRegister;
        ai: taicpu;
        l: TAsmLabel;
      begin
        if (CPURV_HAS_F in cpu_capabilities[current_settings.cputype]) and
          needs_check_for_fpu_exceptions then
          begin
            r:=getintregister(list,OS_INT);
            list.concat(taicpu.op_reg(A_FRFLAGS,r));
            current_asmdata.getjumplabel(l);
            ai:=taicpu.op_reg_reg_sym_ofs(A_Bxx,r,NR_X0,l,0);
            ai.is_jmp:=true;
            ai.condition:=C_EQ;
            list.concat(ai);
            alloccpuregisters(list,R_INTREGISTER,paramanager.get_volatile_registers_int(pocall_default));
            cg.a_call_name(current_asmdata.CurrAsmList,'FPC_THROWFPUEXCEPTION',false);
            dealloccpuregisters(list,R_INTREGISTER,paramanager.get_volatile_registers_int(pocall_default));
            a_label(list,l);
          end;
      end;

end.