fpc/compiler/powerpc/cpubase.pas

{
    $Id$
    Copyright (c) 1998-2000 by Florian Klaempfl

    Contains the base types for the PowerPC

    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 cpubase;

{$i defines.inc}

interface

uses
  strings,cutils,cclasses,aasm,cpuinfo,cginfo;

{$ifndef NOOPT}
Type
{What an instruction can change}
  TInsChange = (Ch_None);
{$endif}

const
{ Size of the instruction table converted by nasmconv.pas }
  instabentries = 1103;
  maxinfolen    = 7;

{ By default we want everything }
{$define ATTOP}
{$define ATTREG}
{$define INTELOP}
{$define ITTABLE}

{ For TP we can't use asmdebug due the table sizes }
{$ifndef TP}
  {$define ASMDEBUG}
{$endif}

{ We Don't need the intel style opcodes if we don't have a intel }
{ reader or generator                                            }
{$undef INTELOP}

{ We Don't need the AT&T style opcodes if we don't have a AT&T
  reader or generator }
{$ifdef NORA386ATT}
  {$ifdef NOAG386ATT}
    {$undef ATTOP}
    {$ifdef NOAG386DIR}
       {$undef ATTREG}
    {$endif}
  {$endif}
{$endif}

type
  TAsmOp=(A_None,
    { normal opcodes }
    a_add, a_add_, a_addo, a_addo_, a_addc, a_addc_, a_addco, a_addco_,
    a_adde, a_adde_, a_addeo, a_addeo_, a_addi, a_addic, a_addic_, a_addis,
    a_addme, a_addme_, a_addmeo, a_addmeo_, a_addze, a_addze_, a_addzeo,
    a_addzeo_, a_and, a_and_, a_andc, a_andc_, a_andi_, a_andis_, a_b,
    a_ba, a_bl, a_bla, a_bc, a_bca, a_bcl, a_bcla, a_bcctr, a_bcctrl, a_bclr,
    a_bclrl, a_cmp, a_cmpi, a_cmpl, a_cmpli, a_cntlzw, a_cntlzw_, a_crand,
    a_crandc, a_creqv, a_crnand, a_crnor, a_cror, a_crorc, a_crxor, a_dcba,
    a_dcbf, a_dcbi, a_dcbst, a_dcbt, a_divw, a_divw_, a_divwo, a_divwo_,
    a_divwu, a_divwu_, a_divwuo, a_divwuo_, a_eciwx, a_ecowx, a_eieio, a_eqv,
    a_eqv_, a_extsb, a_extsb_, a_extsh, a_extsh_, a_fabs, a_fabs_, a_fadd,
    a_fadd_, a_fadds, a_fadds_, a_fcmpo, a_fcmpu, a_fctiw, a_fctw_, a_fctwz,
    a_fctwz_, a_fdiv, a_fdiv_, a_fdivs, a_fdivs_, a_fmadd, a_fmadd_, a_fmadds,
    a_fmadds_, a_fmr, a_fmsub, a_fmsub_, a_fmsubs, a_fmsubs_, a_fmul, a_fmul_,
    a_fmuls, a_fmuls_, a_fnabs, a_fnabs_, a_fneg, a_fneg_, a_fnmadd,
    a_fnmadd_, a_fnmadds, a_fnmadds_, a_fnmsub, a_fnmsub_, a_fnmsubs,
    a_fnmsubs_, a_fres, a_fres_, a_frsp, a_frsp_, a_frsqrte, a_frsqrte_,
    a_fsel, a_fsel_, a_fsqrt, a_fsqrt_, a_fsqrts, a_fsqrts_, a_fsub, a_fsub_,
    a_fsubs, a_fsubs_, a_icbi, a_isync, a_lbz, a_lbzu, a_lbzux, a_lbzx,
    a_lfd, a_lfdu, a_lfdux, a_lfdx, a_lfs, a_lfsu, a_lfsux, a_lfsx, a_lha,
    a_lhau, a_lhaux, a_lhax, a_hbrx, a_lhz, a_lhzu, a_lhzux, a_lhzx, a_lmw,
    a_lswi, a_lswx, a_lwarx, a_lwbrx, a_lwz, a_lwzu, a_lwzux, a_lwzx, a_mcrf,
    a_mcrfs, a_mcrxr, a_lcrxe, a_mfcr, a_mffs, a_maffs_, a_mfmsr, a_mfspr, a_mfsr,
    a_mfsrin, a_mftb, a_mtfcrf, a_a_mtfd0, a_mtfsb1, a_mtfsf, a_mtfsf_,
    a_mtfsfi, a_mtfsfi_, a_mtmsr, a_mtspr, a_mtsr, a_mtsrin, a_mulhw,
    a_mulhw_, a_mulhwu, a_mulhwu_, a_mulli, a_mullw, a_mullw_, a_mullwo,
    a_mullwo_, a_nand, a_nand_, a_neg, a_neg_, a_nego, a_nego_, a_nor, a_nor_,
    a_or, a_or_, a_orc, a_orc_, a_ori, a_oris, a_rfi, a_rlwimi, a_rlwimi_,
    a_rlwinm, a_tlwinm_, a_rlwnm, a_sc, a_slw, a_slw_, a_sraw, a_sraw_,
    a_srawi, a_srawi_,a_srw, a_srw_, a_stb, a_stbu, a_stbux, a_stbx, a_stfd,
    a_stfdu, a_stfdux, a_stfdx, a_stfiwx, a_stfs, a_stfsu, a_stfsux, a_stfsx,
    a_sth, a_sthbrx, a_sthu, a_sthux, a_sthx, a_stmw, a_stswi, a_stswx, a_stw,
    a_stwbrx, a_stwx_, a_stwu, a_stwux, a_stwx, a_subf, a_subf_, a_subfo,
    a_subfo_, a_subfc, a_subfc_, a_subfco, a_subfco_, a_subfe, a_subfe_,
    a_subfeo, a_subfeo_, a_subfic, a_subfme, a_subfme_, a_subfmeo, a_subfmeo_,
    a_subfze, a_subfze_, a_subfzeo, a_subfzeo_, a_sync, a_tlbia, a_tlbie,
    a_tlbsync, a_tw, a_twi, a_xor, a_xor_, a_xori, a_xoris,
    { simplified mnemonics }
    a_subi, a_subis, a_subic, a_subic_, a_sub, a_sub_, a_subo, a_subo_,
    a_subc, a_subc_, a_subco, _subco_, a_cmpwi, a_cmpw, a_cmplwi, a_cmplw,
    a_extlwi, a_extlwi_, a_extrwi, a_extrwi_, a_inslwi, a_inslwi_, a_insrwi,
    a_insrwi_, a_rotlwi, a_rotlwi_, a_rotlw, a_rotlw_, a_slwi, a_slwi_,
    a_srwi, a_srwi_, a_clrlwi, a_clrlwi_, a_clrrwi, a_clrrwi_, a_clrslwi,
    a_clrslwi_, a_blr, a_bctr, a_blrl, a_bctrl, a_crset, a_crclr, a_crmove,
    a_crnot, a_mt {move to special prupose reg}, a_mf {move from special purpose reg},
    a_nop, a_li, a_lis, a_la, a_mr, a_mr_, a_not, a_mtcr);

  op2strtable=array[tasmop] of string[8];

const
  firstop = low(tasmop);
  lastop  = high(tasmop);


{*****************************************************************************
                                  Registers
*****************************************************************************}

type
  tregister = (R_NO,
    R_0,R_1,R_2,R_3,R_4,R_5,R_6,R_7,R_8,R_9,R_10,R_11,R_12,R_13,R_14,R_15,R_16,
    R_17,R_18,R_19,R_20,R_21,R_22,R_23,R_24,R_25,R_26,R_27,R_28,R_29,R_30,R_31,
    R_F0,R_F1,R_F2,R_F3,R_F4,R_F5,R_F6,R_F7,R_F8,R_F9,R_F10,R_F11,R_F12,
    R_F13,R_F14,R_F15,R_F16,R_F17, R_F18,R_F19,R_F20,R_F21,R_F22, R_F23,R_F24,
    R_F25,R_F26,R_F27,R_F28,R_F29,R_F30,R_F31,
    R_M0,R_M1,R_M2,R_M3,R_M4,R_M5,R_M6,R_M7,R_M8,R_M9,R_M10,R_M11,R_M12,
    R_M13,R_M14,R_M15,R_M16,R_M17,R_M18,R_M19,R_M20,R_M21,R_M22, R_M23,R_M24,
    R_M25,R_M26,R_M27,R_M28,R_M29,R_M30,R_M31,

    R_CR,R_CR0,R_CR1,R_CR2,R_CR3,R_CR4,R_CR5,R_CR6,R_CR7,
    R_XER,R_LR,R_CTR,R_FPSCR
  );

  tregisterset = set of tregister;

  reg2strtable = array[tregister] of string[5];

Const
   R_SPR1 = R_XER;
   R_SPR8 = R_LR;
   R_SPR9 = R_CTR;
   R_TOC = R_2;
{   CR0 = 0;
   CR1 = 4;
   CR2 = 8;
   CR3 = 12;
   CR4 = 16;
   CR5 = 20;
   CR6 = 24;
   CR7 = 28;
   LT = 0;
   GT = 1;
   EQ = 2;
   SO = 3;
   FX = 4;
   FEX = 5;
   VX = 6;
   OX = 7;}

  firstreg = low(tregister);
  lastreg  = high(tregister);

  att_reg2str : reg2strtable = ('',
    '0','1','2','3','4','5','6','7','8','9','10','11','12','13','14','15','16',
    '17','18','19','20','21','22','23','24','25','26','27','28','29','30','31',
    'F0','F1','F2','F3','F4','F5','F6','F7', 'F8','F9','F10','F11','F12',
    'F13','F14','F15','F16','F17', 'F18','F19','F20','F21','F22', 'F23','F24',
    'F25','F26','F27','F28','F29','F30','F31',
    'M0','M1','M2','M3','M4','M5','M6','M7','M8','M9','M10','M11','M12',
    'M13','M14','M15','M16','M17','M18','M19','M20','M21','M22', 'M23','M24',
    'M25','M26','M27','M28','M29','M30','M31',
    'CR','CR0','CR1','CR2','CR3','CR4','CR5','CR6','CR7',
    'XER','LR','CTR','FPSCR'
  );

  mot_reg2str : reg2strtable = ('',
    'r0','r1','r2','r3','r4','r5','r6','r7','r8','r9','r10','r11','r12','r13',
    'r14','r15','r16','r17','r18','r19','r20','r21','r22','r23','r24','r25',
    'r26','r27','r28','r29','r30','r31',
    'F0','F1','F2','F3','F4','F5','F6','F7', 'F8','F9','F10','F11','F12',
    'F13','F14','F15','F16','F17', 'F18','F19','F20','F21','F22', 'F23','F24',
    'F25','F26','F27','F28','F29','F30','F31',
    'M0','M1','M2','M3','M4','M5','M6','M7','M8','M9','M10','M11','M12',
    'M13','M14','M15','M16','M17','M18','M19','M20','M21','M22', 'M23','M24',
    'M25','M26','M27','M28','M29','M30','M31',
    'CR','CR0','CR1','CR2','CR3','CR4','CR5','CR6','CR7',
    'XER','LR','CTR','FPSCR'
  );

  { FIX ME !!!!!!!!! }
  ALL_REGISTERS = [R_0..R_FPSCR];


{*****************************************************************************
                                Conditions
*****************************************************************************}

type
{$ifndef tp}
{$minenumsize 1}
{$endif tp}
  TAsmCondFlag = (C_None { unconditional jumps },
    { conditions when not using ctr decrement etc }
    C_LT,C_LE,C_EQ,C_GE,C_GT,C_NL,C_NE,C_NG,C_SO,C_NS,C_UN,C_NU,
    { conditions when using ctr decrement etc }
    C_T,C_F,C_DNZ,C_DNZT,C_DNZF,C_DZ,C_DZT,C_DZF);

const
    { these are in the XER, but when moved to CR_x they correspond with the }
    { bits below (still needs to be verified!!!)                            }
    C_OV = C_EQ;
    C_CA = C_GT;

type

{$ifndef tp}
{$minenumsize default}
{$endif tp}
  TAsmCond = packed record
               case simple: boolean of
                 false: (BO, BI: byte);
                 true: (
                   cond: TAsmCondFlag;
                   case byte of
                     0: ();
                     { specifies in which part of the cr the bit has to be }
                     { tested for blt,bgt,beq,..,bnu                       }
                     1: (cr: R_CR0..R_CR7);
                     { specifies the bit to test for bt,bf,bdz,..,bdzf }
                     2: (crbit: byte)
                   );
             end;

const
  AsmCondFlag2BO: Array[C_T..C_DZF] of Byte =
    (12,4,16,8,0,18,10,2);
  AsmCondFlag2BI: Array[C_LT..C_NU] of Byte =
    (0,1,2,0,1,0,2,1,3,3,3,3);
  AsmCondFlagTF: Array[TAsmCondFlag] of Boolean =
    (false,true,false,true,false,true,false,false,false,true,false,true,false,
     true,false,false,true,false,false,true,false);


  AsmCondFlag2Str: Array[TAsmCondFlag] of string[4] = ({cf_none}'',
     { conditions when not using ctr decrement etc}
     'lt','le','eq','ge','gt','nl','ne','ng','so','ns','un','nu',
     't','f','dnz','dzt','dnzf','dz','dzt','dzf');



const
  CondAsmOps=3;
  CondAsmOp:array[0..CondAsmOps-1] of TasmOp=(
     A_BC, A_TW, A_TWI
  );
{*****************************************************************************
                                   Flags
*****************************************************************************}

type
  TResFlagsEnum = (F_EQ,F_NE,F_LT,F_LE,F_GT,F_GE,F_SO,F_FX,F_FEX,F_VX,F_OX);
  TResFlags = record
    cr: R_CR0..R_CR7;
    flag: TResFlagsEnum;
  end;

(*
const
  { arrays for boolean location conversions }

  flag_2_cond : array[TResFlags] of TAsmCond =
     (C_E,C_NE,C_LT,C_LE,C_GT,C_GE,???????????????);
*)

{*****************************************************************************
                                Reference
*****************************************************************************}

type

  { since we have only 16 offsets, we need to be able to specify the high }
  { and low 16 bits of the address of a symbol                            }
  trefsymaddr = (refs_full,refs_ha,refs_l);

  { immediate/reference record }
  preference = ^treference;
  treference = packed record
     is_immediate: boolean; { is this used as reference or immediate }
     base, index : tregister;
     offset      : longint;
     symbol      : tasmsymbol;
     symaddr     : trefsymaddr;
     offsetfixup : longint;
     alignment   : byte;
  end;

const symaddr2str: array[trefsymaddr] of string[3] = ('','@ha','@l');


{*****************************************************************************
                                Operand
*****************************************************************************}

type
  toptype=(top_none,top_reg,top_ref,top_const,top_symbol,top_bool);

  toper=record
    ot  : longint;
    case typ : toptype of
     top_none   : ();
     top_reg    : (reg:tregister);
     top_ref    : (ref:preference);
     top_const  : (val:aword);
     top_symbol : (sym:tasmsymbol;symofs:longint);
     top_bool  :  (b: boolean);
  end;


{*****************************************************************************
                               Generic Location
*****************************************************************************}

type
  TLoc=(
    LOC_INVALID,     { added for tracking problems}
    LOC_CONSTANT,    { ordinal constant }
    LOC_REGISTER,    { in a processor register }
    LOC_CREGISTER,   { Constant register which shouldn't be modified }
    LOC_FPUREGISTER, { FPU register}
    LOC_CFPUREGISTER,{ Constant FPU register which shouldn't be modified }
    LOC_MMREGISTER,  { multimedia register }
    LOC_CMMREGISTER, { Constant multimedia reg which shouldn't be modified }
    LOC_REFERENCE,   { in memory }
    LOC_CREFERENCE,  { in memory (constant) }
    LOC_JUMP,        { boolean results only, jump to false or true label }
    LOC_FLAGS        { boolean results only, flags are set }
  );

  plocation = ^tlocation;
  tlocation = packed record
     size : TCGSize;
     case loc : tloc of
        LOC_CREFERENCE,LOC_REFERENCE : (reference : treference);
        LOC_CONSTANT : (
          case longint of
            1 : (value : AWord);
            2 : (valuelow, valuehigh:AWord);
          );
        LOC_FPUREGISTER, LOC_CFPUREGISTER, LOC_MMREGISTER, LOC_CMMREGISTER,
          LOC_REGISTER,LOC_CREGISTER : (
            case longint of
              1 : (registerlow,registerhigh : tregister);
              { overlay a registerlow }
              2 : (register : tregister);
            );

        LOC_JUMP : ();
        LOC_FLAGS : (resflags : tresflags);
        LOC_INVALID : ();

        { segment in reference at the same place as in loc_register }
  end;


{*****************************************************************************
                                 Constants
*****************************************************************************}

const
  usableregsint = [R_13..R_30];
  usableregsfpu = [R_F14..R_F31];
  usableregsmm  = [R_M14..R_M31];

  firstsaveintreg = R_13;
  lastsaveintreg = R_30;
  firstsavefpureg = R_F14;
  lastsavefpureg = R_F31;
{ no altivec support yet. Need to override tcgobj.a_loadmm_* first in tcgppc }
  firstsavemmreg = R_NO;
  lastsavemmreg = R_NO;

  lvaluelocations = [LOC_REFERENCE, LOC_CREGISTER, LOC_CFPUREGISTER,
                     LOC_CMMREGISTER];

  c_countusableregsint = 21;
  c_countusableregsfpu = 32;
  c_countusableregsmm  = 32;

  max_operands = 5;

  maxvarregs = 18;

  varregs : Array [1..maxvarregs] of Tregister =
            (R_13,R_14,R_15,R_16,R_17,R_18,R_19,R_20,R_21,R_22,R_23,R_24,R_25,
             R_26,R_27,R_28,R_29,R_30);

  maxfpuvarregs = 31-14+1;

  fpuvarregs : Array [1..maxfpuvarregs] of Tregister =
            (R_F14,R_F15,R_F16,R_F17,R_F18,R_F19,R_F20,R_F21,R_F22,R_F23,
             R_F24,R_F25,R_F26,R_F27,R_F28,R_F29,R_F30,R_F31);


  max_param_regs_int = 8;
  param_regs_int: Array[1..max_param_regs_int] of tregister =
    (R_3,R_4,R_5,R_6,R_7,R_8,R_9,R_10);

  max_param_regs_fpu = 13;
  param_regs_fpu: Array[1..max_param_regs_fpu] of tregister =
    (R_F1,R_F2,R_F3,R_F4,R_F5,R_F6,R_F7,R_F8,R_F9,R_F10,R_F11,R_F12,R_F13);


  max_param_regs_mm = 13;
  param_regs_mm: Array[1..max_param_regs_mm] of tregister =
    (R_M1,R_M2,R_M3,R_M4,R_M5,R_M6,R_M7,R_M8,R_M9,R_M10,R_M11,R_M12,R_M13);

  general_registers = [R_0..R_31];

  intregs = [R_0..R_31];
  fpuregs = [R_F0..R_F31];
  mmregs = [R_M0..R_M31];



  { generic register names }
  stack_pointer_reg= R_1;
  R_RTOC           = R_2;
  frame_pointer_reg    = stack_pointer_reg;
  self_pointer_reg  = R_9;
  accumulator      = R_3;
  accumulatorhigh  = R_4;
  max_scratch_regs = 3;
  scratch_regs: Array[1..max_scratch_regs] of TRegister = (R_11,R_12,R_31);

  maxintregs = maxvarregs;
  maxfpuregs = maxfpuvarregs;

{ low and high of the available maximum width integer general purpose }
{ registers                                                           }
  LoGPReg = R_0;
  HiGPReg = R_31;

{ low and high of every possible width general purpose register (same as }
{ above on most architctures apart from the 80x86)                       }
  LoReg = R_0;
  HiReg = R_31;

  { sizes }
  extended_size = 8;

  LinkageAreaSize = 24;
 { offset in the linkage area for the saved stack pointer }
  LA_SP = 0;
 { offset in the linkage area for the saved conditional register}
  LA_CR = 4;
 { offset in the linkage area for the saved link register}
  LA_LR = 8;
 { offset in the linkage area for the saved RTOC register}
  LA_RTOC = 20;
  
{*****************************************************************************
                       GCC /ABI linking information
*****************************************************************************}

  {# Registers which must be saved when calling a routine declared as
     cppdecl, cdecl, stdcall, safecall, palmossyscall. The registers
     saved should be the ones as defined in the target ABI and / or GCC.
     
     This value can be deduced from CALLED_USED_REGISTERS array in the
     GCC source.
  }
  std_saved_registers = [R_13..R_29];
  {# Required parameter alignment when calling a routine declared as
     stdcall and cdecl. The alignment value should be the one defined
     by GCC or the target ABI. 
     
     The value of this constant is equal to the constant 
     PARM_BOUNDARY / BITS_PER_UNIT in the GCC source.
  }     
  std_param_align = 4;  { for 32-bit version only }
  

{*****************************************************************************
                                  Helpers
*****************************************************************************}

    { resets all values of ref to defaults }
    procedure reset_reference(var ref : treference);
    { set mostly used values of a new reference }
    function new_reference(base : tregister;offset : longint) : preference;

    function newreference(const r : treference) : preference;
    procedure disposereference(var r : preference);


    function is_calljmp(o:tasmop):boolean;

    procedure inverse_cond(c: TAsmCond;var r : TAsmCond);
    function flags_to_cond(const f: TResFlags) : TAsmCond;
    procedure create_cond_imm(BO,BI:byte;var r : TAsmCond);
    procedure create_cond_norm(cond: TAsmCondFlag; cr: byte;var r : TasmCond);

    procedure clear_location(var loc : tlocation);
    procedure set_location(var destloc,sourceloc : tlocation);
    procedure swap_location(var destloc,sourceloc : tlocation);

{*****************************************************************************
                                  Init/Done
*****************************************************************************}

  procedure InitCpu;
  procedure DoneCpu;


implementation

  uses
      verbose
{$ifdef heaptrc}
      ,ppheap
{$endif heaptrc}
      ;
{*****************************************************************************
                                  Helpers
*****************************************************************************}



    function is_calljmp(o:tasmop):boolean;
      begin
       is_calljmp:=false;
        case o of
          A_B,A_BA,A_BL,A_BLA,A_BC,A_BCA,A_BCL,A_BCLA,A_BCCTR,A_BCCTRL,A_BCLR,
            A_BCLRL,A_TW,A_TWI: is_calljmp:=true;
        end;
      end;

    procedure disposereference(var r : preference);
      begin
         dispose(r);
         r:=nil;
      end;


    function newreference(const r : treference) : preference;
      var
         p : preference;
      begin
         new(p);
         p^:=r;
         newreference:=p;
      end;

    procedure reset_reference(var ref : treference);
      begin
        FillChar(ref,sizeof(treference),0)
      end;

    function new_reference(base : tregister;offset : longint) : preference;
    var
      r : preference;
    begin
      new(r);
      FillChar(r^,sizeof(treference),0);
      r^.base:=base;
      r^.offset:=offset;
      new_reference:=r;
    end;



    procedure inverse_cond(c: TAsmCond;var r : TAsmCond);
    const
      inv_condflags:array[TAsmCondFlag] of TAsmCondFlag=(C_None,
        C_GE,C_GT,C_NE,C_LT,C_LE,C_LT,C_EQ,C_GT,C_NS,C_SO,C_NU,C_UN,
        C_F,C_T,C_DNZ,C_DNZF,C_DNZT,C_DZ,C_DZF,C_DZT);
    begin
      c.cond := inv_condflags[c.cond];
      r := c;
    end;

    function flags_to_cond(const f: TResFlags) : TAsmCond;
      const
        flag_2_cond: array[F_EQ..F_SO] of TAsmCondFlag =
          (C_EQ,C_NE,C_LT,C_LE,C_GT,C_GE,C_SO);
      begin
        if f.flag > high(flag_2_cond) then
          internalerror(200112301);
        result.simple := true;
        result.cr := f.cr;
        result.cond := flag_2_cond[f.flag];
      end;

    procedure create_cond_imm(BO,BI:byte;var r : TAsmCond);
    begin
      r.simple := false;
      r.bo := bo;
      r.bi := bi;
    end;

    procedure create_cond_norm(cond: TAsmCondFlag; cr: byte;var r : TasmCond);
    const cr2reg: array[0..7] of tregister =
            (R_CR0,R_CR1,R_CR2,R_CR3,R_CR4,R_CR5,R_CR6,R_CR7);
    begin
      r.simple := true;
      r.cond := cond;
      case cond of
        C_NONE:;
        C_T..C_DZF: r.crbit := cr
        else r.cr := cr2reg[cr];
      end;
    end;

    procedure clear_location(var loc : tlocation);

      begin
        loc.loc:=LOC_INVALID;
      end;

    {This is needed if you want to be able to delete the string with the nodes !!}
    procedure set_location(var destloc,sourceloc : tlocation);

      begin
        destloc:= sourceloc;
      end;

    procedure swap_location(var destloc,sourceloc : tlocation);

      var
         swapl : tlocation;

      begin
         swapl := destloc;
         destloc := sourceloc;
         sourceloc := swapl;
      end;

{*****************************************************************************
                                  Init/Done
*****************************************************************************}

  procedure InitCpu;
    begin
    end;

  procedure DoneCpu;
    begin
    end;

end.
{
  $Log$
  Revision 1.9  2002-04-21 15:48:39  carl
  * some small updates according to i386 version

  Revision 1.8  2002/04/20 21:41:51  carl
  * renamed some constants

  Revision 1.7  2002/04/06 18:13:02  jonas
    * several powerpc-related additions and fixes

  Revision 1.6  2001/12/30 17:24:48  jonas
    * range checking is now processor independent (part in cgobj, part in
    cg64f32) and should work correctly again (it needed some changes after
    the changes of the low and high of tordef's to int64)
  * maketojumpbool() is now processor independent (in ncgutil)
  * getregister32 is now called getregisterint

  Revision 1.5  2001/12/29 15:28:58  jonas
    * powerpc/cgcpu.pas compiles :)
    * several powerpc-related fixes
    * cpuasm unit is now based on common tainst unit
    + nppcmat unit for powerpc (almost complete)

  Revision 1.4  2001/09/28 20:40:05  jonas
    * several additions, almost complete (only some problems with resflags left)

  Revision 1.3  2001/09/06 15:25:56  jonas
    * changed type of tcg from object to class ->  abstract methods are now
      a lot cleaner :)
    + more updates: load_*_loc methods, op_*_* methods, g_flags2reg method
      (if possible with geenric implementation and necessary ppc
       implementations)
    * worked a bit further on cgflw, now working on exitnode

  Revision 1.2  2001/08/26 13:31:04  florian
    * some cg reorganisation
    * some PPC updates

  Revision 1.2  2001/08/26 13:29:34  florian
    * some cg reorganisation
    * some PPC updates

  Revision 1.1  2000/07/13 06:30:12  michael
    + Initial import

  Revision 1.15  2000/05/01 11:04:49  jonas
    * changed NOT to A_NOP

  Revision 1.14  2000/04/29 09:01:06  jonas
    * nmem compiles again (at least for powerpc)

  Revision 1.13  2000/03/26 16:38:06  jonas
    * frame_pointer = stackpointer instead of R_NO

  Revision 1.12  2000/01/07 01:14:58  peter
    * updated copyright to 2000

  Revision 1.11  1999/12/24 22:48:10  jonas
    * compiles again

  Revision 1.10  1999/11/09 22:57:09  peter
    * compiles again both i386,alpha both with optimizer

  Revision 1.9  1999/10/20 12:21:34  jonas
    * changed scratch_registers to (R_11,_R12,R_30) because R_0 is a special
      case and R_31 is used as some kind of frame pointer under LinuxPPC

  Revision 1.8  1999/10/14 14:57:55  florian
    - removed the hcodegen use in the new cg, use cgbase instead

  Revision 1.7  1999/09/15 20:35:47  florian
    * small fix to operator overloading when in MMX mode
    + the compiler uses now fldz and fld1 if possible
    + some fixes to floating point registers
    + some math. functions (arctan, ln, sin, cos, sqrt, sqr, pi) are now inlined
    * .... ???

  Revision 1.6  1999/09/03 13:11:59  jonas
    * several changes to the way conditional branches are handled\n  * some typos fixed

  Revision 1.5  1999/08/23 23:27:54  pierre
    + dummy InitCpu/DoneCpu

  Revision 1.4  1999/08/06 16:41:12  jonas
    * PowerPC compiles again, several routines implemented in cgcpu.pas
    * added constant to cpubase of alpha and powerpc for maximum
      number of operands

  Revision 1.3  1999/08/05 14:58:18  florian
    * some fixes for the floating point registers
    * more things for the new code generator

  Revision 1.2  1999/08/04 12:59:25  jonas
    * all tokes now start with an underscore
    * PowerPC compiles!!

  Revision 1.1  1999/08/03 23:37:53  jonas
    + initial implementation for PowerPC based on the Alpha stuff

}