freepascal.compiler/compiler/mips/ncpumat.pas

{
David Zhang 2007/01/15
    $Id: ncpumat.pas,v 1.23 2005/02/14 17:13:10 peter Exp $
    Copyright (c) 1998-2002 by Florian Klaempfl

    Generate MIPSel assembler for math nodes

    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 ncpumat;

{$i fpcdefs.inc}

interface

uses
  node, nmat, ncgmat, cgbase;

type
  tMIPSELmoddivnode = class(tmoddivnode)
    procedure pass_generate_code;override;
  end;

  tMIPSELshlshrnode = class(tshlshrnode)
    procedure pass_generate_code;override;
    { everything will be handled in pass_2 }
    function first_shlshr64bitint: tnode; override;
  end;

  tMIPSELnotnode = class(tcgnotnode)
    procedure second_boolean; override;
  end;

  TMIPSunaryminusnode = class(tcgunaryminusnode)
    procedure emit_float_sign_change(r: tregister; _size : tcgsize);override;
  end;

implementation

uses
  globtype, systems,
  cutils, verbose, globals,
  symconst, symdef,
  aasmbase, aasmcpu, aasmtai, aasmdata,
  defutil,
  procinfo,
  cgobj, hlcgobj, pass_2,
  ncon,
  cpubase,
  ncgutil, cgcpu, cgutils;

{*****************************************************************************
                             TMipselMODDIVNODE
*****************************************************************************}

const
  ops_div: array[boolean] of tasmop = (A_DIVU, A_DIV);

procedure tMIPSELmoddivnode.pass_generate_code;
var
  power: longint;
  tmpreg, numerator, divider: tregister;
  hl,hl2: tasmlabel;
begin
  secondpass(left);
  secondpass(right);
  location_reset(location,LOC_REGISTER,def_cgsize(resultdef));
  location.register:=cg.GetIntRegister(current_asmdata.CurrAsmList,OS_INT);

  { put numerator in register }
  hlcg.location_force_reg(current_asmdata.CurrAsmList, left.location, left.resultdef, left.resultdef, True);
  numerator := left.location.Register;

  if (nodetype = divn) and
    (right.nodetype = ordconstn) and
    ispowerof2(tordconstnode(right).Value.svalue, power) then
  begin
    tmpreg := cg.GetIntRegister(current_asmdata.CurrAsmList, OS_INT);
    cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SAR, OS_INT, 31, numerator, tmpreg);
    { if signed, tmpreg=right value-1, otherwise 0 }
    cg.a_op_const_reg(current_asmdata.CurrAsmList, OP_AND, OS_INT, tordconstnode(right).Value.svalue - 1, tmpreg);
    { add left value }
    cg.a_op_reg_reg(current_asmdata.CurrAsmList, OP_ADD, OS_INT, numerator, tmpreg);
    cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SAR, OS_INT, aword(power), tmpreg, location.register);
  end
  else
  begin
    { load divider in a register if necessary }
    hlcg.location_force_reg(current_asmdata.CurrAsmList, right.location,
      right.resultdef, right.resultdef, True);
    divider := right.location.Register;

    { GAS performs division in delay slot:

          bne   denom,$zero,.L1
          div   $zero,numerator,denom
          break 7
     .L1:
          mflo  result

      We can't yet do the same without prior fixing the spilling code:
      if registers require spilling, loads can be inserted before 'div',
      resulting in invalid code.
    }
    current_asmdata.CurrAsmList.Concat(taicpu.op_reg_reg_reg(ops_div[is_signed(resultdef)],NR_R0,numerator,divider));
    { Check for zero denominator, omit if dividing by constant (constants are checked earlier) }
    if (right.nodetype<>ordconstn) then
    begin
      current_asmdata.getjumplabel(hl);
      cg.a_cmp_reg_reg_label(current_asmdata.CurrAsmList,OS_INT,OC_NE,divider,NR_R0,hl);
      current_asmdata.CurrAsmList.Concat(taicpu.op_const(A_BREAK,7));
      cg.a_label(current_asmdata.CurrAsmList,hl);
    end;

    { Dividing low(longint) by -1 will overflow }
    if is_signed(right.resultdef) and (cs_check_overflow in current_settings.localswitches) then
    begin
      current_asmdata.getjumplabel(hl2);
      current_asmdata.CurrAsmList.concat(taicpu.op_reg_reg_const(A_ADDIU,NR_R1,NR_R0,-1));
      cg.a_cmp_reg_reg_label(current_asmdata.CurrAsmList,OS_INT,OC_NE,divider,NR_R1,hl2);
      current_asmdata.CurrAsmList.concat(taicpu.op_reg_const(A_LUI,NR_R1,$8000));
      cg.a_cmp_reg_reg_label(current_asmdata.CurrAsmList,OS_INT,OC_NE,numerator,NR_R1,hl2);
      current_asmdata.CurrAsmList.concat(taicpu.op_const(A_BREAK,6));
      cg.a_label(current_asmdata.CurrAsmList,hl2);
    end;

   if (nodetype=modn) then
     current_asmdata.CurrAsmList.concat(taicpu.op_reg(A_MFHI,location.register))
   else
     current_asmdata.CurrAsmList.concat(taicpu.op_reg(A_MFLO,location.register));
  end;
end;


{*****************************************************************************
                             TMIPSelSHLRSHRNODE
*****************************************************************************}

function TMIPSELShlShrNode.first_shlshr64bitint: TNode;
begin
  { 64bit without constants need a helper }
  if is_64bit(left.resultdef) and
    (right.nodetype <> ordconstn) then
  begin
    Result := inherited first_shlshr64bitint;
    exit;
  end;

  Result := nil;
end;


procedure tMIPSELshlshrnode.pass_generate_code;
var
  hregister, hreg64hi, hreg64lo: tregister;
  op: topcg;
  shiftval: aword;
begin
  { 64bit without constants need a helper, and is
          already replaced in pass1 }
  if is_64bit(left.resultdef) and
    (right.nodetype <> ordconstn) then
    internalerror(200405301);

  secondpass(left);
  secondpass(right);
  if is_64bit(left.resultdef) then
  begin
    location_reset(location, LOC_REGISTER, OS_64);

    { load left operator in a register }
    hlcg.location_force_reg(current_asmdata.CurrAsmList, left.location, left.resultdef, u64inttype, False);


    hreg64hi := left.location.register64.reghi;
    hreg64lo := left.location.register64.reglo;

    shiftval := tordconstnode(right).Value.svalue and 63;
    if shiftval > 31 then
    begin
      if nodetype = shln then
      begin
        cg.a_load_const_reg(current_asmdata.CurrAsmList, OS_32, 0, hreg64hi);
        if (shiftval and 31) <> 0 then
          cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHL, OS_32, shiftval and 31, hreg64lo, hreg64lo);
      end
      else
      begin
        cg.a_load_const_reg(current_asmdata.CurrAsmList, OS_32, 0, hreg64lo);
        if (shiftval and 31) <> 0 then
          cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHR, OS_32, shiftval and 31, hreg64hi, hreg64hi);
      end;
      location.register64.reglo := hreg64hi;
      location.register64.reghi := hreg64lo;
    end
    else
    begin
      if shiftval <> 0 then
        begin
          hregister := cg.getintregister(current_asmdata.CurrAsmList, OS_32);
          if nodetype = shln then
            begin
              cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHR, OS_32, 32 - shiftval, hreg64lo, hregister);
              cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHL, OS_32, shiftval, hreg64hi, hreg64hi);
              cg.a_op_reg_reg_reg(current_asmdata.CurrAsmList, OP_OR, OS_32, hregister, hreg64hi, hreg64hi);
              cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHL, OS_32, shiftval, hreg64lo, hreg64lo);
            end
          else
            begin
              cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHL, OS_32, 32 - shiftval, hreg64hi, hregister);
              cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHR, OS_32, shiftval, hreg64lo, hreg64lo);
              cg.a_op_reg_reg_reg(current_asmdata.CurrAsmList, OP_OR, OS_32, hregister, hreg64lo, hreg64lo);
              cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, OP_SHR, OS_32, shiftval, hreg64hi, hreg64hi);
            end;
        end;
      location.register64.reghi := hreg64hi;
      location.register64.reglo := hreg64lo;
    end;
  end
  else
  begin
    { load left operators in a register }
    hlcg.location_force_reg(current_asmdata.CurrAsmList, left.location, left.resultdef, left.resultdef, True);
    location_reset(location,LOC_REGISTER,def_cgsize(resultdef));
    location.register:=cg.GetIntRegister(current_asmdata.CurrAsmList,OS_INT);
    { determine operator }
    if nodetype = shln then
      op := OP_SHL
    else
      op := OP_SHR;
    { shifting by a constant directly coded: }
    if (right.nodetype = ordconstn) then
    begin
      if tordconstnode(right).Value.svalue and 31 <> 0 then
        cg.a_op_const_reg_reg(current_asmdata.CurrAsmList, op, OS_32, tordconstnode(right).Value.svalue and 31, left.location.register, location.register);
    end
    else
    begin
      { load shift count in a register if necessary }
      hlcg.location_force_reg(current_asmdata.CurrAsmList, right.location, right.resultdef, right.resultdef, True);
      cg.a_op_reg_reg_reg(current_asmdata.CurrAsmList, op, OS_32, right.location.Register, left.location.register, location.register);
    end;
  end;
end;


{*****************************************************************************
                               TMIPSelNOTNODE
*****************************************************************************}

procedure tMIPSELnotnode.second_boolean;
var
  hl: tasmlabel;
  tmpreg : TRegister;
  r64: TRegister64;
begin
  { if the location is LOC_JUMP, we do the secondpass after the
          labels are allocated
        }
  if left.expectloc = LOC_JUMP then
  begin
    hl := current_procinfo.CurrTrueLabel;
    current_procinfo.CurrTrueLabel := current_procinfo.CurrFalseLabel;
    current_procinfo.CurrFalseLabel := hl;
    secondpass(left);
    maketojumpbool(current_asmdata.CurrAsmList, left, lr_load_regvars);
    hl := current_procinfo.CurrTrueLabel;
    current_procinfo.CurrTrueLabel := current_procinfo.CurrFalseLabel;
    current_procinfo.CurrFalseLabel := hl;
    location.loc := LOC_JUMP;
  end
  else
  begin
    secondpass(left);
    case left.location.loc of
      LOC_REGISTER, LOC_CREGISTER, LOC_REFERENCE, LOC_CREFERENCE,
      LOC_SUBSETREG,LOC_CSUBSETREG,LOC_SUBSETREF,LOC_CSUBSETREF:
      begin
        hlcg.location_force_reg(current_asmdata.CurrAsmList, left.location, left.resultdef, left.resultdef, True);
        location_reset(location,LOC_FLAGS,OS_NO);
        location.resflags.reg2:=NR_R0;
        location.resflags.cond:=OC_EQ;
        if is_64bit(resultdef) then
          begin
            tmpreg:=cg.GetIntRegister(current_asmdata.CurrAsmList,OS_INT);
            { OR low and high parts together }
            current_asmdata.CurrAsmList.concat(taicpu.op_reg_reg_reg(A_OR,tmpreg,left.location.register64.reglo,left.location.register64.reghi));
            location.resflags.reg1:=tmpreg;
          end
        else
          location.resflags.reg1:=left.location.register;
      end;
      else
        internalerror(2003042401);
    end;
  end;
end;


{*****************************************************************************
                               TMIPSunaryminusnode
*****************************************************************************}

procedure TMIPSunaryminusnode.emit_float_sign_change(r: tregister; _size : tcgsize);
begin
  case _size of
    OS_F32:
      current_asmdata.CurrAsmList.concat(taicpu.op_reg_reg(A_NEG_s,r,r));
    OS_F64:
      current_asmdata.CurrAsmList.concat(taicpu.op_reg_reg(A_NEG_d,r,r));
  else
    internalerror(2013030501);
  end;
end;


begin
  cmoddivnode := tMIPSELmoddivnode;
  cshlshrnode := tMIPSELshlshrnode;
  cnotnode    := tMIPSELnotnode;
  cunaryminusnode := TMIPSunaryminusnode;
end.