fpc/compiler/ncgcon.pas

531 lines
20 KiB
ObjectPascal

{
$Id$
Copyright (c) 1998-2000 by Florian Klaempfl
Generate assembler for constant nodes which are the same for
all (most) processors
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 ncgcon;
{$i defines.inc}
interface
uses
node,ncon;
type
tcgrealconstnode = class(trealconstnode)
procedure pass_2;override;
end;
tcgordconstnode = class(tordconstnode)
procedure pass_2;override;
end;
tcgpointerconstnode = class(tpointerconstnode)
procedure pass_2;override;
end;
tcgstringconstnode = class(tstringconstnode)
procedure pass_2;override;
end;
tcgsetconstnode = class(tsetconstnode)
procedure pass_2;override;
end;
tcgnilnode = class(tnilnode)
procedure pass_2;override;
end;
tcgguidconstnode = class(tguidconstnode)
procedure pass_2;override;
end;
implementation
uses
globtype,widestr,systems,
verbose,globals,
symconst,symdef,aasm,types,
temp_gen,
cpubase,
tgcpu;
{*****************************************************************************
TCGREALCONSTNODE
*****************************************************************************}
procedure tcgrealconstnode.pass_2;
{ I suppose the parser/pass_1 must make sure the generated real }
{ constants are actually supported by the target processor? (JM) }
const
floattype2ait:array[tfloattype] of tait=
(ait_real_32bit,ait_real_64bit,ait_real_80bit,ait_comp_64bit);
var
hp1 : tai;
lastlabel : tasmlabel;
realait : tait;
begin
lastlabel:=nil;
realait:=floattype2ait[tfloatdef(resulttype.def).typ];
{ const already used ? }
if not assigned(lab_real) then
begin
{ tries to find an old entry }
hp1:=tai(Consts.first);
while assigned(hp1) do
begin
if hp1.typ=ait_label then
lastlabel:=tai_label(hp1).l
else
begin
if (hp1.typ=realait) and (lastlabel<>nil) then
begin
if(
((realait=ait_real_32bit) and (tai_real_32bit(hp1).value=value_real)) or
((realait=ait_real_64bit) and (tai_real_64bit(hp1).value=value_real)) or
((realait=ait_real_80bit) and (tai_real_80bit(hp1).value=value_real)) or
((realait=ait_comp_64bit) and (tai_comp_64bit(hp1).value=value_real))
) then
begin
{ found! }
lab_real:=lastlabel;
break;
end;
end;
lastlabel:=nil;
end;
hp1:=tai(hp1.next);
end;
{ :-(, we must generate a new entry }
if not assigned(lab_real) then
begin
getdatalabel(lastlabel);
lab_real:=lastlabel;
if (cs_create_smart in aktmoduleswitches) then
Consts.concat(Tai_cut.Create);
Consts.concat(Tai_label.Create(lastlabel));
case realait of
ait_real_32bit :
Consts.concat(Tai_real_32bit.Create(value_real));
ait_real_64bit :
Consts.concat(Tai_real_64bit.Create(value_real));
ait_real_80bit :
Consts.concat(Tai_real_80bit.Create(value_real));
ait_comp_64bit :
Consts.concat(Tai_comp_64bit.Create(value_real));
else
internalerror(10120);
end;
end;
end;
reset_reference(location.reference);
location.reference.symbol:=lab_real;
location.loc:=LOC_MEM;
end;
{*****************************************************************************
TCGORDCONSTNODE
*****************************************************************************}
procedure tcgordconstnode.pass_2;
var
l : tasmlabel;
begin
location.loc:=LOC_MEM;
{ still needs to be made more generic (and optimal), this is for }
{ when Peter implements LOC_ORDCONST (JM) }
if is_64bitint(resulttype.def) then
begin
getdatalabel(l);
if (cs_create_smart in aktmoduleswitches) then
Consts.concat(Tai_cut.Create);
Consts.concat(Tai_label.Create(l));
Consts.concat(Tai_const.Create_32bit(longint(lo(value))));
Consts.concat(Tai_const.Create_32bit(longint(hi(value))));
reset_reference(location.reference);
location.reference.symbol:=l;
end
else
begin
{ non int64 const. behaves as a memory reference }
location.reference.is_immediate:=true;
location.reference.offset:=longint(value);
end;
end;
{*****************************************************************************
TCGPOINTERCONSTNODE
*****************************************************************************}
procedure tcgpointerconstnode.pass_2;
begin
{ an integer const. behaves as a memory reference }
location.loc:=LOC_MEM;
location.reference.is_immediate:=true;
location.reference.offset:=longint(value);
end;
{*****************************************************************************
TCGSTRINGCONSTNODE
*****************************************************************************}
procedure tcgstringconstnode.pass_2;
var
hp1 : tai;
l1,l2,
lastlabel : tasmlabel;
pc : pchar;
same_string : boolean;
l,j,
i,mylength : longint;
begin
{ for empty ansistrings we could return a constant 0 }
if (is_ansistring(resulttype.def) or
is_widestring(resulttype.def)) and
(len=0) then
begin
location.loc:=LOC_MEM;
location.reference.is_immediate:=true;
location.reference.offset:=0;
exit;
end;
{ const already used ? }
lastlabel:=nil;
if not assigned(lab_str) then
begin
if is_shortstring(resulttype.def) then
mylength:=len+2
else
mylength:=len+1;
{ widestrings can't be reused yet }
if not(is_widestring(resulttype.def)) then
begin
{ tries to found an old entry }
hp1:=tai(Consts.first);
while assigned(hp1) do
begin
if hp1.typ=ait_label then
lastlabel:=tai_label(hp1).l
else
begin
{ when changing that code, be careful that }
{ you don't use typed consts, which are }
{ are also written to consts }
{ currently, this is no problem, because }
{ typed consts have no leading length or }
{ they have no trailing zero }
if (hp1.typ=ait_string) and (lastlabel<>nil) and
(tai_string(hp1).len=mylength) then
begin
same_string:=true;
{ if shortstring then check the length byte first and
set the start index to 1 }
if is_shortstring(resulttype.def) then
begin
if len<>ord(tai_string(hp1).str[0]) then
same_string:=false;
j:=1;
end
else
j:=0;
{ don't check if the length byte was already wrong }
if same_string then
begin
for i:=0 to len do
begin
if tai_string(hp1).str[j]<>value_str[i] then
begin
same_string:=false;
break;
end;
inc(j);
end;
end;
{ found ? }
if same_string then
begin
lab_str:=lastlabel;
{ create a new entry for ansistrings, but reuse the data }
if (st_type in [st_ansistring,st_widestring]) then
begin
getdatalabel(l2);
Consts.concat(Tai_label.Create(l2));
Consts.concat(Tai_const_symbol.Create(lab_str));
{ return the offset of the real string }
lab_str:=l2;
end;
break;
end;
end;
lastlabel:=nil;
end;
hp1:=tai(hp1.next);
end;
end;
{ :-(, we must generate a new entry }
if not assigned(lab_str) then
begin
getdatalabel(lastlabel);
lab_str:=lastlabel;
if (cs_create_smart in aktmoduleswitches) then
Consts.concat(Tai_cut.Create);
Consts.concat(Tai_label.Create(lastlabel));
{ generate an ansi string ? }
case st_type of
st_ansistring:
begin
{ an empty ansi string is nil! }
if len=0 then
Consts.concat(Tai_const.Create_32bit(0))
else
begin
getdatalabel(l1);
getdatalabel(l2);
Consts.concat(Tai_label.Create(l2));
Consts.concat(Tai_const_symbol.Create(l1));
Consts.concat(Tai_const.Create_32bit(len));
Consts.concat(Tai_const.Create_32bit(len));
Consts.concat(Tai_const.Create_32bit(-1));
Consts.concat(Tai_label.Create(l1));
getmem(pc,len+2);
move(value_str^,pc^,len);
pc[len]:=#0;
{ to overcome this problem we set the length explicitly }
{ with the ending null char }
Consts.concat(Tai_string.Create_length_pchar(pc,len+1));
{ return the offset of the real string }
lab_str:=l2;
end;
end;
st_widestring:
begin
{ an empty wide string is nil! }
if len=0 then
Consts.concat(Tai_const.Create_32bit(0))
else
begin
getdatalabel(l1);
getdatalabel(l2);
Consts.concat(Tai_label.Create(l2));
Consts.concat(Tai_const_symbol.Create(l1));
{ we use always UTF-16 coding for constants }
{ at least for now }
{ Consts.concat(Tai_const.Create_8bit(2)); }
Consts.concat(Tai_const.Create_32bit(len));
Consts.concat(Tai_const.Create_32bit(len));
Consts.concat(Tai_const.Create_32bit(-1));
Consts.concat(Tai_label.Create(l1));
for i:=0 to len-1 do
Consts.concat(Tai_const.Create_16bit(pcompilerwidestring(value_str)^.data[i]));
{ return the offset of the real string }
lab_str:=l2;
end;
end;
st_shortstring:
begin
{ truncate strings larger than 255 chars }
if len>255 then
l:=255
else
l:=len;
{ also length and terminating zero }
getmem(pc,l+3);
move(value_str^,pc[1],l+1);
pc[0]:=chr(l);
{ to overcome this problem we set the length explicitly }
{ with the ending null char }
pc[l+1]:=#0;
Consts.concat(Tai_string.Create_length_pchar(pc,l+2));
end;
end;
end;
end;
reset_reference(location.reference);
location.reference.symbol:=lab_str;
location.loc:=LOC_MEM;
end;
{*****************************************************************************
TCGSETCONSTNODE
*****************************************************************************}
procedure tcgsetconstnode.pass_2;
var
hp1 : tai;
lastlabel : tasmlabel;
i : longint;
neededtyp : tait;
begin
{ small sets are loaded as constants }
if tsetdef(resulttype.def).settype=smallset then
begin
location.loc:=LOC_MEM;
location.reference.is_immediate:=true;
location.reference.offset:=plongint(value_set)^;
exit;
end;
neededtyp:=ait_const_8bit;
lastlabel:=nil;
{ const already used ? }
if not assigned(lab_set) then
begin
{ tries to found an old entry }
hp1:=tai(Consts.first);
while assigned(hp1) do
begin
if hp1.typ=ait_label then
lastlabel:=tai_label(hp1).l
else
begin
if (lastlabel<>nil) and (hp1.typ=neededtyp) then
begin
if (hp1.typ=ait_const_8bit) then
begin
{ compare normal set }
i:=0;
while assigned(hp1) and (i<32) do
begin
if tai_const(hp1).value<>value_set^[i] then
break;
inc(i);
hp1:=tai(hp1.next);
end;
if i=32 then
begin
{ found! }
lab_set:=lastlabel;
break;
end;
{ leave when the end of consts is reached, so no
hp1.next is done }
if not assigned(hp1) then
break;
end
else
begin
{ compare small set }
if plongint(value_set)^=tai_const(hp1).value then
begin
{ found! }
lab_set:=lastlabel;
break;
end;
end;
end;
lastlabel:=nil;
end;
hp1:=tai(hp1.next);
end;
{ :-(, we must generate a new entry }
if not assigned(lab_set) then
begin
getdatalabel(lastlabel);
lab_set:=lastlabel;
if (cs_create_smart in aktmoduleswitches) then
Consts.concat(Tai_cut.Create);
Consts.concat(Tai_label.Create(lastlabel));
if tsetdef(resulttype.def).settype=smallset then
begin
move(value_set^,i,sizeof(longint));
Consts.concat(Tai_const.Create_32bit(i));
end
else
begin
for i:=0 to 31 do
Consts.concat(Tai_const.Create_8bit(value_set^[i]));
end;
end;
end;
reset_reference(location.reference);
location.reference.symbol:=lab_set;
location.loc:=LOC_MEM;
end;
{*****************************************************************************
TCGNILNODE
*****************************************************************************}
procedure tcgnilnode.pass_2;
begin
location.loc:=LOC_MEM;
location.reference.is_immediate:=true;
location.reference.offset:=0;
end;
{*****************************************************************************
TCGPOINTERCONSTNODE
*****************************************************************************}
procedure tcgguidconstnode.pass_2;
var
tmplabel : TAsmLabel;
i : integer;
begin
location.loc:=LOC_MEM;
{ label for GUID }
getdatalabel(tmplabel);
consts.concat(Tai_label.Create(tmplabel));
consts.concat(Tai_const.Create_32bit(value.D1));
consts.concat(Tai_const.Create_16bit(value.D2));
consts.concat(Tai_const.Create_16bit(value.D3));
for i:=Low(value.D4) to High(value.D4) do
consts.concat(Tai_const.Create_8bit(value.D4[i]));
reset_reference(location.reference);
location.reference.symbol:=tmplabel;
end;
begin
crealconstnode:=tcgrealconstnode;
cordconstnode:=tcgordconstnode;
cpointerconstnode:=tcgpointerconstnode;
cstringconstnode:=tcgstringconstnode;
csetconstnode:=tcgsetconstnode;
cnilnode:=tcgnilnode;
cguidconstnode:=tcgguidconstnode;
end.
{
$Log$
Revision 1.3 2001-12-31 09:52:02 jonas
* empty widestrings can also be optimized to the constant '0'
Revision 1.2 2001/10/20 19:28:37 peter
* interface 2 guid support
* guid constants support
Revision 1.1 2001/09/30 16:17:17 jonas
* made most constant and mem handling processor independent
}