fpc/compiler/assemble.pas
Károly Balogh 7e1051324d include exec on Amiga only in the implementation part
git-svn-id: trunk@27065 -
2014-03-09 23:05:13 +00:00

1793 lines
58 KiB
ObjectPascal

{
Copyright (c) 1998-2004 by Peter Vreman
This unit handles the assemblerfile write and assembler calls of FPC
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.
****************************************************************************
}
{# @abstract(This unit handles the assembler file write and assembler calls of FPC)
Handles the calls to the actual external assemblers, as well as the generation
of object files for smart linking. Also contains the base class for writing
the assembler statements to file.
}
unit assemble;
{$i fpcdefs.inc}
interface
uses
SysUtils,
systems,globtype,globals,aasmbase,aasmtai,aasmdata,ogbase,finput;
const
{ maximum of aasmoutput lists there will be }
maxoutputlists = ord(high(tasmlisttype))+1;
{ buffer size for writing the .s file }
AsmOutSize=32768*4;
type
TAssembler=class(TObject)
public
{filenames}
path : TPathStr;
name : string;
AsmFileName, { current .s and .o file }
ObjFileName,
ppufilename : TPathStr;
asmprefix : string;
SmartAsm : boolean;
SmartFilesCount,
SmartHeaderCount : longint;
Constructor Create(smart:boolean);virtual;
Destructor Destroy;override;
procedure NextSmartName(place:tcutplace);
procedure MakeObject;virtual;abstract;
end;
{# This is the base class which should be overridden for each each
assembler writer. It is used to actually assembler a file,
and write the output to the assembler file.
}
TExternalAssembler=class(TAssembler)
private
procedure CreateSmartLinkPath(const s:TPathStr);
protected
{outfile}
AsmSize,
AsmStartSize,
outcnt : longint;
outbuf : array[0..AsmOutSize-1] of char;
outfile : file;
ioerror : boolean;
{input source info}
lastfileinfo : tfileposinfo;
infile,
lastinfile : tinputfile;
{last section type written}
lastsectype : TAsmSectionType;
procedure WriteSourceLine(hp: tailineinfo);
procedure WriteTempalloc(hp: tai_tempalloc);
public
{# Returns the complete path and executable name of the assembler
program.
It first tries looking in the UTIL directory if specified,
otherwise it searches in the free pascal binary directory, in
the current working directory and then in the directories
in the $PATH environment.}
Function FindAssembler:string;
{# Actually does the call to the assembler file. Returns false
if the assembling of the file failed.}
Function CallAssembler(const command:string; const para:TCmdStr):Boolean;
Function DoAssemble:boolean;virtual;
Procedure RemoveAsm;virtual;
Procedure AsmFlush;
Procedure AsmClear;
{# Write a string to the assembler file }
Procedure AsmWrite(const c:char);
Procedure AsmWrite(const s:string);
Procedure AsmWrite(const s:ansistring);
{# Write a string to the assembler file }
Procedure AsmWritePChar(p:pchar);
{# Write a string to the assembler file followed by a new line }
Procedure AsmWriteLn(const c:char);
Procedure AsmWriteLn(const s:string);
Procedure AsmWriteLn(const s:ansistring);
{# Write a new line to the assembler file }
Procedure AsmLn;
procedure AsmCreate(Aplace:tcutplace);
procedure AsmClose;
{# This routine should be overridden for each assembler, it is used
to actually write the abstract assembler stream to file.}
procedure WriteTree(p:TAsmList);virtual;
{# This routine should be overridden for each assembler, it is used
to actually write all the different abstract assembler streams
by calling for each stream type, the @var(WriteTree) method.}
procedure WriteAsmList;virtual;
{# Constructs the command line for calling the assembler }
function MakeCmdLine: TCmdStr; virtual;
public
Constructor Create(smart:boolean);override;
procedure MakeObject;override;
end;
{ TInternalAssembler }
TInternalAssembler=class(TAssembler)
private
FCObjOutput : TObjOutputclass;
{ the aasmoutput lists that need to be processed }
lists : byte;
list : array[1..maxoutputlists] of TAsmList;
{ current processing }
currlistidx : byte;
currlist : TAsmList;
procedure WriteStab(p:pchar);
function MaybeNextList(var hp:Tai):boolean;
function SetIndirectToSymbol(hp: Tai; const indirectname: string): Boolean;
function TreePass0(hp:Tai):Tai;
function TreePass1(hp:Tai):Tai;
function TreePass2(hp:Tai):Tai;
procedure writetree;
procedure writetreesmart;
protected
ObjData : TObjData;
ObjOutput : tObjOutput;
property CObjOutput:TObjOutputclass read FCObjOutput write FCObjOutput;
public
constructor create(smart:boolean);override;
destructor destroy;override;
procedure MakeObject;override;
end;
TAssemblerClass = class of TAssembler;
Procedure GenerateAsm(smart:boolean);
Procedure OnlyAsm;
procedure RegisterAssembler(const r:tasminfo;c:TAssemblerClass);
Implementation
uses
{$ifdef hasamiga}
exec,
{$endif}
{$ifdef hasunix}
unix,
{$endif}
cutils,cfileutl,
{$ifdef memdebug}
cclasses,
{$endif memdebug}
script,fmodule,verbose,
{$if defined(m68k) or defined(arm)}
cpuinfo,
{$endif m68k or arm}
aasmcpu,
owbase,owar
;
var
CAssembler : array[tasm] of TAssemblerClass;
function fixline(s:string):string;
{
return s with all leading and ending spaces and tabs removed
}
var
i,j,k : integer;
begin
i:=length(s);
while (i>0) and (s[i] in [#9,' ']) do
dec(i);
j:=1;
while (j<i) and (s[j] in [#9,' ']) do
inc(j);
for k:=j to i do
if s[k] in [#0..#31,#127..#255] then
s[k]:='.';
fixline:=Copy(s,j,i-j+1);
end;
{*****************************************************************************
TAssembler
*****************************************************************************}
Constructor TAssembler.Create(smart:boolean);
begin
{ load start values }
AsmFileName:=current_module.AsmFilename;
ObjFileName:=current_module.ObjFileName;
name:=Lower(current_module.modulename^);
path:=current_module.outputpath;
asmprefix := current_module.asmprefix^;
if current_module.outputpath = '' then
ppufilename := ''
else
ppufilename := current_module.ppufilename;
SmartAsm:=smart;
SmartFilesCount:=0;
SmartHeaderCount:=0;
SmartLinkOFiles.Clear;
end;
Destructor TAssembler.Destroy;
begin
end;
procedure TAssembler.NextSmartName(place:tcutplace);
var
s : string;
begin
inc(SmartFilesCount);
if SmartFilesCount>999999 then
Message(asmw_f_too_many_asm_files);
case place of
cut_begin :
begin
inc(SmartHeaderCount);
s:=asmprefix+tostr(SmartHeaderCount)+'h';
end;
cut_normal :
s:=asmprefix+tostr(SmartHeaderCount)+'s';
cut_end :
s:=asmprefix+tostr(SmartHeaderCount)+'t';
end;
AsmFileName:=Path+FixFileName(s+tostr(SmartFilesCount)+target_info.asmext);
ObjFileName:=Path+FixFileName(s+tostr(SmartFilesCount)+target_info.objext);
{ insert in container so it can be cleared after the linking }
SmartLinkOFiles.Insert(ObjFileName);
end;
{*****************************************************************************
TExternalAssembler
*****************************************************************************}
Function DoPipe:boolean;
begin
DoPipe:=(cs_asm_pipe in current_settings.globalswitches) and
(([cs_asm_extern,cs_asm_leave,cs_link_on_target] * current_settings.globalswitches) = []) and
((target_asm.id in [as_gas,as_ggas,as_darwin,as_powerpc_xcoff]));
end;
Constructor TExternalAssembler.Create(smart:boolean);
begin
inherited Create(smart);
if SmartAsm then
begin
path:=FixPath(ChangeFileExt(AsmFileName,target_info.smartext),false);
CreateSmartLinkPath(path);
end;
Outcnt:=0;
end;
procedure TExternalAssembler.CreateSmartLinkPath(const s:TPathStr);
procedure DeleteFilesWithExt(const AExt:string);
var
dir : TRawByteSearchRec;
begin
if findfirst(FixPath(s,false)+'*'+AExt,faAnyFile,dir) = 0 then
begin
repeat
DeleteFile(s+source_info.dirsep+dir.name);
until findnext(dir) <> 0;
end;
findclose(dir);
end;
var
hs : TPathStr;
begin
if PathExists(s,false) then
begin
{ the path exists, now we clean only all the .o and .s files }
DeleteFilesWithExt(target_info.objext);
DeleteFilesWithExt(target_info.asmext);
end
else
begin
hs:=s;
if hs[length(hs)] in ['/','\'] then
delete(hs,length(hs),1);
{$push} {$I-}
mkdir(hs);
{$pop}
if ioresult<>0 then;
end;
end;
const
lastas : byte=255;
var
LastASBin : TCmdStr;
Function TExternalAssembler.FindAssembler:string;
var
asfound : boolean;
UtilExe : string;
begin
asfound:=false;
if cs_link_on_target in current_settings.globalswitches then
begin
{ If linking on target, don't add any path PM }
FindAssembler:=utilsprefix+ChangeFileExt(target_asm.asmbin,target_info.exeext);
exit;
end
else
UtilExe:=utilsprefix+ChangeFileExt(target_asm.asmbin,source_info.exeext);
if lastas<>ord(target_asm.id) then
begin
lastas:=ord(target_asm.id);
{ is an assembler passed ? }
if utilsdirectory<>'' then
asfound:=FindFile(UtilExe,utilsdirectory,false,LastASBin);
if not AsFound then
asfound:=FindExe(UtilExe,false,LastASBin);
if (not asfound) and not(cs_asm_extern in current_settings.globalswitches) then
begin
Message1(exec_e_assembler_not_found,LastASBin);
current_settings.globalswitches:=current_settings.globalswitches+[cs_asm_extern];
end;
if asfound then
Message1(exec_t_using_assembler,LastASBin);
end;
FindAssembler:=LastASBin;
end;
Function TExternalAssembler.CallAssembler(const command:string; const para:TCmdStr):Boolean;
var
DosExitCode : Integer;
begin
result:=true;
if (cs_asm_extern in current_settings.globalswitches) then
begin
AsmRes.AddAsmCommand(command,para,name);
exit;
end;
try
FlushOutput;
DosExitCode:=RequotedExecuteProcess(command,para);
if DosExitCode<>0
then begin
Message1(exec_e_error_while_assembling,tostr(dosexitcode));
result:=false;
end;
except on E:EOSError do
begin
Message1(exec_e_cant_call_assembler,tostr(E.ErrorCode));
current_settings.globalswitches:=current_settings.globalswitches+[cs_asm_extern];
result:=false;
end;
end;
end;
procedure TExternalAssembler.RemoveAsm;
var
g : file;
begin
if cs_asm_leave in current_settings.globalswitches then
exit;
if cs_asm_extern in current_settings.globalswitches then
AsmRes.AddDeleteCommand(AsmFileName)
else
begin
assign(g,AsmFileName);
{$push} {$I-}
erase(g);
{$pop}
if ioresult<>0 then;
end;
end;
Function TExternalAssembler.DoAssemble:boolean;
begin
DoAssemble:=true;
if DoPipe then
exit;
if not(cs_asm_extern in current_settings.globalswitches) then
begin
if SmartAsm then
begin
if (SmartFilesCount<=1) then
Message1(exec_i_assembling_smart,name);
end
else
Message1(exec_i_assembling,name);
end;
if CallAssembler(FindAssembler,MakeCmdLine) then
RemoveAsm
else
begin
DoAssemble:=false;
GenerateError;
end;
end;
Procedure TExternalAssembler.AsmFlush;
begin
if outcnt>0 then
begin
{ suppress i/o error }
{$push} {$I-}
BlockWrite(outfile,outbuf,outcnt);
{$pop}
ioerror:=ioerror or (ioresult<>0);
outcnt:=0;
end;
end;
Procedure TExternalAssembler.AsmClear;
begin
outcnt:=0;
end;
Procedure TExternalAssembler.AsmWrite(const c: char);
begin
if OutCnt+1>=AsmOutSize then
AsmFlush;
OutBuf[OutCnt]:=c;
inc(OutCnt);
inc(AsmSize);
end;
Procedure TExternalAssembler.AsmWrite(const s:string);
begin
if OutCnt+length(s)>=AsmOutSize then
AsmFlush;
Move(s[1],OutBuf[OutCnt],length(s));
inc(OutCnt,length(s));
inc(AsmSize,length(s));
end;
Procedure TExternalAssembler.AsmWrite(const s:ansistring);
var
StartIndex, ToWrite: longint;
begin
if s='' then
exit;
if OutCnt+length(s)>=AsmOutSize then
AsmFlush;
StartIndex:=1;
ToWrite:=length(s);
while ToWrite>AsmOutSize do
begin
Move(s[StartIndex],OutBuf[OutCnt],AsmOutSize);
inc(OutCnt,AsmOutSize);
inc(AsmSize,AsmOutSize);
AsmFlush;
inc(StartIndex,AsmOutSize);
dec(ToWrite,AsmOutSize);
end;
Move(s[StartIndex],OutBuf[OutCnt],ToWrite);
inc(OutCnt,ToWrite);
inc(AsmSize,ToWrite);
end;
procedure TExternalAssembler.AsmWriteLn(const c: char);
begin
AsmWrite(c);
AsmLn;
end;
Procedure TExternalAssembler.AsmWriteLn(const s:string);
begin
AsmWrite(s);
AsmLn;
end;
Procedure TExternalAssembler.AsmWriteLn(const s: ansistring);
begin
AsmWrite(s);
AsmLn;
end;
Procedure TExternalAssembler.AsmWritePChar(p:pchar);
var
i,j : longint;
begin
i:=StrLen(p);
j:=i;
while j>0 do
begin
i:=min(j,AsmOutSize);
if OutCnt+i>=AsmOutSize then
AsmFlush;
Move(p[0],OutBuf[OutCnt],i);
inc(OutCnt,i);
inc(AsmSize,i);
dec(j,i);
p:=pchar(@p[i]);
end;
end;
Procedure TExternalAssembler.AsmLn;
begin
if OutCnt>=AsmOutSize-2 then
AsmFlush;
if (cs_link_on_target in current_settings.globalswitches) then
begin
OutBuf[OutCnt]:=target_info.newline[1];
inc(OutCnt);
inc(AsmSize);
if length(target_info.newline)>1 then
begin
OutBuf[OutCnt]:=target_info.newline[2];
inc(OutCnt);
inc(AsmSize);
end;
end
else
begin
OutBuf[OutCnt]:=source_info.newline[1];
inc(OutCnt);
inc(AsmSize);
if length(source_info.newline)>1 then
begin
OutBuf[OutCnt]:=source_info.newline[2];
inc(OutCnt);
inc(AsmSize);
end;
end;
end;
function TExternalAssembler.MakeCmdLine: TCmdStr;
begin
result:=target_asm.asmcmd;
{$ifdef arm}
if (target_info.system=system_arm_darwin) then
Replace(result,'$ARCH',lower(cputypestr[current_settings.cputype]));
{$endif arm}
if (cs_link_on_target in current_settings.globalswitches) then
begin
Replace(result,'$ASM',maybequoted(ScriptFixFileName(AsmFileName)));
Replace(result,'$OBJ',maybequoted(ScriptFixFileName(ObjFileName)));
end
else
begin
{$ifdef hasunix}
if DoPipe then
Replace(result,'$ASM','')
else
{$endif}
Replace(result,'$ASM',maybequoted(AsmFileName));
Replace(result,'$OBJ',maybequoted(ObjFileName));
end;
if (cs_create_pic in current_settings.moduleswitches) then
Replace(result,'$PIC','-KPIC')
else
Replace(result,'$PIC','');
if (cs_asm_source in current_settings.globalswitches) then
Replace(result,'$NOWARN','')
else
Replace(result,'$NOWARN','-W');
Replace(result,'$EXTRAOPT',asmextraopt);
end;
procedure TExternalAssembler.AsmCreate(Aplace:tcutplace);
{$ifdef hasamiga}
var
tempFileName: TPathStr;
{$endif}
begin
if SmartAsm then
NextSmartName(Aplace);
{$ifdef hasamiga}
{ on Amiga/MorphOS try to redirect .s files to the T: assign, which is
for temp files, and usually (default setting) located in the RAM: drive.
This highly improves assembling speed for complex projects like the
compiler itself, especially on hardware with slow disk I/O.
Consider this as a poor man's pipe on Amiga, because real pipe handling
would be much more complex and error prone to implement. (KB) }
if (([cs_asm_extern,cs_asm_leave,cs_link_on_target] * current_settings.globalswitches) = []) then
begin
{ try to have an unique name for the .s file }
tempFileName:=HexStr(FindTask(nil))+ExtractFileName(AsmFileName);
{$ifndef morphos}
{ old Amiga RAM: handler only allows filenames up to 30 char }
if Length(tempFileName) < 30 then
{$endif}
AsmFileName:='T:'+tempFileName;
end;
{$endif}
{$ifdef hasunix}
if DoPipe then
begin
if SmartAsm then
begin
if (SmartFilesCount<=1) then
Message1(exec_i_assembling_smart,name);
end
else
Message1(exec_i_assembling_pipe,AsmFileName);
POpen(outfile,maybequoted(FindAssembler)+' '+MakeCmdLine,'W');
end
else
{$endif}
begin
Assign(outfile,AsmFileName);
{$push} {$I-}
Rewrite(outfile,1);
{$pop}
if ioresult<>0 then
begin
ioerror:=true;
Message1(exec_d_cant_create_asmfile,AsmFileName);
end;
end;
outcnt:=0;
AsmSize:=0;
AsmStartSize:=0;
end;
procedure TExternalAssembler.AsmClose;
var
f : file;
FileAge : longint;
begin
AsmFlush;
{$ifdef hasunix}
if DoPipe then
begin
if PClose(outfile) <> 0 then
GenerateError;
end
else
{$endif}
begin
{Touch Assembler time to ppu time is there is a ppufilename}
if ppufilename<>'' then
begin
Assign(f,ppufilename);
{$push} {$I-}
reset(f,1);
{$pop}
if ioresult=0 then
begin
FileAge := FileGetDate(GetFileHandle(f));
close(f);
reset(outfile,1);
FileSetDate(GetFileHandle(outFile),FileAge);
end;
end;
close(outfile);
end;
end;
procedure TExternalAssembler.WriteSourceLine(hp: tailineinfo);
var
module : tmodule;
begin
{ load infile }
if (lastfileinfo.moduleindex<>hp.fileinfo.moduleindex) or
(lastfileinfo.fileindex<>hp.fileinfo.fileindex) then
begin
{ in case of a generic the module can be different }
if current_module.unit_index=hp.fileinfo.moduleindex then
module:=current_module
else
module:=get_module(hp.fileinfo.moduleindex);
{ during the compilation of the system unit there are cases when
the fileinfo contains just zeros => invalid }
if assigned(module) then
infile:=module.sourcefiles.get_file(hp.fileinfo.fileindex)
else
infile:=nil;
if assigned(infile) then
begin
{ open only if needed !! }
if (cs_asm_source in current_settings.globalswitches) then
infile.open;
end;
{ avoid unnecessary reopens of the same file !! }
lastfileinfo.fileindex:=hp.fileinfo.fileindex;
lastfileinfo.moduleindex:=hp.fileinfo.moduleindex;
{ be sure to change line !! }
lastfileinfo.line:=-1;
end;
{ write source }
if (cs_asm_source in current_settings.globalswitches) and
assigned(infile) then
begin
if (infile<>lastinfile) then
begin
AsmWriteLn(target_asm.comment+'['+infile.name+']');
if assigned(lastinfile) then
lastinfile.close;
end;
if (hp.fileinfo.line<>lastfileinfo.line) and
(hp.fileinfo.line<infile.maxlinebuf) then
begin
if (hp.fileinfo.line<>0) and
(infile.linebuf^[hp.fileinfo.line]>=0) then
AsmWriteLn(target_asm.comment+'['+tostr(hp.fileinfo.line)+'] '+
fixline(infile.GetLineStr(hp.fileinfo.line)));
{ set it to a negative value !
to make that is has been read already !! PM }
if (infile.linebuf^[hp.fileinfo.line]>=0) then
infile.linebuf^[hp.fileinfo.line]:=-infile.linebuf^[hp.fileinfo.line]-1;
end;
end;
lastfileinfo:=hp.fileinfo;
lastinfile:=infile;
end;
procedure TExternalAssembler.WriteTempalloc(hp: tai_tempalloc);
begin
{$ifdef EXTDEBUG}
if assigned(hp.problem) then
AsmWriteLn(target_asm.comment+'Temp '+tostr(hp.temppos)+','+
tostr(hp.tempsize)+' '+hp.problem^)
else
{$endif EXTDEBUG}
AsmWriteLn(target_asm.comment+'Temp '+tostr(hp.temppos)+','+
tostr(hp.tempsize)+' '+tempallocstr[hp.allocation]);
end;
procedure TExternalAssembler.WriteTree(p:TAsmList);
begin
end;
procedure TExternalAssembler.WriteAsmList;
begin
end;
procedure TExternalAssembler.MakeObject;
begin
AsmCreate(cut_normal);
FillChar(lastfileinfo, sizeof(lastfileinfo), 0);
lastfileinfo.line := -1;
lastinfile := nil;
lastsectype := sec_none;
WriteAsmList;
AsmClose;
if not(ioerror) then
DoAssemble;
end;
{*****************************************************************************
TInternalAssembler
*****************************************************************************}
constructor TInternalAssembler.create(smart:boolean);
begin
inherited create(smart);
ObjOutput:=nil;
ObjData:=nil;
SmartAsm:=smart;
end;
destructor TInternalAssembler.destroy;
begin
if assigned(ObjData) then
ObjData.free;
if assigned(ObjOutput) then
ObjOutput.free;
end;
procedure TInternalAssembler.WriteStab(p:pchar);
function consumecomma(var p:pchar):boolean;
begin
while (p^=' ') do
inc(p);
result:=(p^=',');
inc(p);
end;
function consumenumber(var p:pchar;out value:longint):boolean;
var
hs : string;
len,
code : integer;
begin
value:=0;
while (p^=' ') do
inc(p);
len:=0;
while (p^ in ['0'..'9']) do
begin
inc(len);
hs[len]:=p^;
inc(p);
end;
if len>0 then
begin
hs[0]:=chr(len);
val(hs,value,code);
end
else
code:=-1;
result:=(code=0);
end;
function consumeoffset(var p:pchar;out relocsym:tobjsymbol;out value:longint):boolean;
var
hs : string;
len,
code : integer;
pstart : pchar;
sym : tobjsymbol;
exprvalue : longint;
gotmin,
have_first_symbol,
have_second_symbol,
dosub : boolean;
begin
result:=false;
value:=0;
relocsym:=nil;
gotmin:=false;
have_first_symbol:=false;
have_second_symbol:=false;
repeat
dosub:=false;
exprvalue:=0;
if gotmin then
begin
dosub:=true;
gotmin:=false;
end;
while (p^=' ') do
inc(p);
case p^ of
#0 :
break;
' ' :
inc(p);
'0'..'9' :
begin
len:=0;
while (p^ in ['0'..'9']) do
begin
inc(len);
hs[len]:=p^;
inc(p);
end;
hs[0]:=chr(len);
val(hs,exprvalue,code);
if code<>0 then
internalerror(200702251);
end;
'.','_',
'A'..'Z',
'a'..'z' :
begin
pstart:=p;
while not(p^ in [#0,' ','-','+']) do
inc(p);
len:=p-pstart;
if len>255 then
internalerror(200509187);
move(pstart^,hs[1],len);
hs[0]:=chr(len);
sym:=objdata.symbolref(hs);
{ Second symbol? }
if assigned(relocsym) then
begin
if have_second_symbol then
internalerror(2007032201);
have_second_symbol:=true;
if not have_first_symbol then
internalerror(2007032202);
{ second symbol should substracted to first }
if not dosub then
internalerror(2007032203);
if (relocsym.objsection<>sym.objsection) then
internalerror(2005091810);
exprvalue:=relocsym.address-sym.address;
relocsym:=nil;
dosub:=false;
end
else
begin
relocsym:=sym;
if assigned(sym.objsection) then
begin
{ first symbol should be + }
if not have_first_symbol and dosub then
internalerror(2007032204);
have_first_symbol:=true;
end;
end;
end;
'+' :
begin
{ nothing, by default addition is done }
inc(p);
end;
'-' :
begin
gotmin:=true;
inc(p);
end;
else
internalerror(200509189);
end;
if dosub then
dec(value,exprvalue)
else
inc(value,exprvalue);
until false;
result:=true;
end;
var
stabstrlen,
ofs,
nline,
nidx,
nother,
i : longint;
stab : TObjStabEntry;
relocsym : TObjSymbol;
pstr,
pcurr,
pendquote : pchar;
oldsec : TObjSection;
begin
pcurr:=nil;
pstr:=nil;
pendquote:=nil;
relocsym:=nil;
ofs:=0;
{ Parse string part }
if (p[0]='"') then
begin
pstr:=@p[1];
{ Ignore \" inside the string }
i:=1;
while not((p[i]='"') and (p[i-1]<>'\')) and
(p[i]<>#0) do
inc(i);
pendquote:=@p[i];
pendquote^:=#0;
pcurr:=@p[i+1];
if not consumecomma(pcurr) then
internalerror(200509181);
end
else
pcurr:=p;
{ When in pass 1 then only alloc and leave }
if ObjData.currpass=1 then
begin
ObjData.StabsSec.Alloc(sizeof(TObjStabEntry));
if assigned(pstr) and (pstr[0]<>#0) then
ObjData.StabStrSec.Alloc(strlen(pstr)+1);
end
else
begin
{ Stabs format: nidx,nother,nline[,offset] }
if not consumenumber(pcurr,nidx) then
internalerror(200509182);
if not consumecomma(pcurr) then
internalerror(200509183);
if not consumenumber(pcurr,nother) then
internalerror(200509184);
if not consumecomma(pcurr) then
internalerror(200509185);
if not consumenumber(pcurr,nline) then
internalerror(200509186);
if consumecomma(pcurr) then
consumeoffset(pcurr,relocsym,ofs);
{ Generate stab entry }
if assigned(pstr) and (pstr[0]<>#0) then
begin
stabstrlen:=strlen(pstr);
{$ifdef optimizestabs}
StabStrEntry:=nil;
if (nidx=N_SourceFile) or (nidx=N_IncludeFile) then
begin
hs:=strpas(pstr);
StabstrEntry:=StabStrDict.Find(hs);
if not assigned(StabstrEntry) then
begin
StabstrEntry:=TStabStrEntry.Create(hs);
StabstrEntry:=StabStrSec.Size;
StabStrDict.Insert(StabstrEntry);
{ generate new stab }
StabstrEntry:=nil;
end;
end;
if assigned(StabstrEntry) then
stab.strpos:=StabstrEntry.strpos
else
{$endif optimizestabs}
begin
stab.strpos:=ObjData.StabStrSec.Size;
ObjData.StabStrSec.write(pstr^,stabstrlen+1);
end;
end
else
stab.strpos:=0;
stab.ntype:=byte(nidx);
stab.ndesc:=word(nline);
stab.nother:=byte(nother);
stab.nvalue:=ofs;
{ Write the stab first without the value field. Then
write a the value field with relocation }
oldsec:=ObjData.CurrObjSec;
ObjData.SetSection(ObjData.StabsSec);
ObjData.Writebytes(stab,sizeof(TObjStabEntry)-4);
ObjData.Writereloc(stab.nvalue,4,relocsym,RELOC_ABSOLUTE32);
ObjData.setsection(oldsec);
end;
if assigned(pendquote) then
pendquote^:='"';
end;
function TInternalAssembler.MaybeNextList(var hp:Tai):boolean;
begin
{ maybe end of list }
while not assigned(hp) do
begin
if currlistidx<lists then
begin
inc(currlistidx);
currlist:=list[currlistidx];
hp:=Tai(currList.first);
end
else
begin
MaybeNextList:=false;
exit;
end;
end;
MaybeNextList:=true;
end;
function TInternalAssembler.SetIndirectToSymbol(hp: Tai; const indirectname: string): Boolean;
var
objsym : TObjSymbol;
indsym : TObjSymbol;
begin
Result:=
Assigned(hp) and
(hp.typ=ait_symbol);
if not Result then
Exit;
objsym:=Objdata.SymbolRef(tai_symbol(hp).sym);
objsym.size:=0;
indsym := TObjSymbol(ObjData.ObjSymbolList.Find(indirectname));
if not Assigned(indsym) then
begin
{ it's possible that indirect symbol is not present in the list,
so we must create it as undefined }
indsym:=TObjSymbol.Create(ObjData.ObjSymbolList, indirectname);
indsym.typ:=AT_NONE;
indsym.bind:=AB_NONE;
end;
objsym.indsymbol:=indsym;
Result:=true;
end;
function TInternalAssembler.TreePass0(hp:Tai):Tai;
var
objsym,
objsymend : TObjSymbol;
begin
while assigned(hp) do
begin
case hp.typ of
ait_align :
begin
if tai_align_abstract(hp).aligntype>1 then
begin
{ always use the maximum fillsize in this pass to avoid possible
short jumps to become out of range }
Tai_align_abstract(hp).fillsize:=Tai_align_abstract(hp).aligntype;
ObjData.alloc(Tai_align_abstract(hp).fillsize);
{ may need to increase alignment of section }
if tai_align_abstract(hp).aligntype>ObjData.CurrObjSec.secalign then
ObjData.CurrObjSec.secalign:=tai_align_abstract(hp).aligntype;
end
else
Tai_align_abstract(hp).fillsize:=0;
end;
ait_datablock :
begin
{$ifdef USE_COMM_IN_BSS}
if writingpackages and
Tai_datablock(hp).is_global then
ObjData.SymbolDefine(Tai_datablock(hp).sym)
else
{$endif USE_COMM_IN_BSS}
begin
ObjData.allocalign(used_align(size_2_align(Tai_datablock(hp).size),0,ObjData.CurrObjSec.secalign));
ObjData.SymbolDefine(Tai_datablock(hp).sym);
ObjData.alloc(Tai_datablock(hp).size);
end;
end;
ait_real_80bit :
ObjData.alloc(tai_real_80bit(hp).savesize);
ait_real_64bit :
ObjData.alloc(8);
ait_real_32bit :
ObjData.alloc(4);
ait_comp_64bit :
ObjData.alloc(8);
ait_const:
begin
{ if symbols are provided we can calculate the value for relative symbols.
This is required for length calculation of leb128 constants }
if assigned(tai_const(hp).sym) then
begin
objsym:=Objdata.SymbolRef(tai_const(hp).sym);
{ objsym already defined and there is endsym? }
if assigned(objsym.objsection) and assigned(tai_const(hp).endsym) then
begin
objsymend:=Objdata.SymbolRef(tai_const(hp).endsym);
{ objsymend already defined? }
if assigned(objsymend.objsection) then
begin
if objsymend.objsection<>objsym.objsection then
begin
{ leb128 relative constants are not relocatable, but other types are,
given that objsym belongs to the current section. }
if (Tai_const(hp).consttype in [aitconst_uleb128bit,aitconst_sleb128bit]) or
(objsym.objsection<>ObjData.CurrObjSec) then
InternalError(200404124);
end
else
Tai_const(hp).value:=objsymend.address-objsym.address+Tai_const(hp).symofs;
end;
end;
end;
ObjData.alloc(tai_const(hp).size);
end;
ait_directive:
begin
case tai_directive(hp).directive of
asd_indirect_symbol:
{ handled in TreePass1 }
;
asd_lazy_reference:
begin
if tai_directive(hp).name='' then
Internalerror(2009112101);
objsym:=ObjData.symbolref(tai_directive(hp).name);
objsym.bind:=AB_LAZY;
end;
asd_reference:
{ ignore for now, but should be added}
;
else
internalerror(2010011101);
end;
end;
ait_section:
begin
ObjData.CreateSection(Tai_section(hp).sectype,Tai_section(hp).name^,Tai_section(hp).secorder);
Tai_section(hp).sec:=ObjData.CurrObjSec;
end;
ait_symbol :
begin
{ needs extra support in the internal assembler }
{ the value is just ignored }
{if tai_symbol(hp).has_value then
internalerror(2009090804); ;}
ObjData.SymbolDefine(Tai_symbol(hp).sym);
end;
ait_label :
ObjData.SymbolDefine(Tai_label(hp).labsym);
ait_string :
ObjData.alloc(Tai_string(hp).len);
ait_instruction :
begin
{ reset instructions which could change in pass 2 }
Taicpu(hp).resetpass2;
ObjData.alloc(Taicpu(hp).Pass1(ObjData));
end;
ait_cutobject :
if SmartAsm then
break;
end;
hp:=Tai(hp.next);
end;
TreePass0:=hp;
end;
function TInternalAssembler.TreePass1(hp:Tai):Tai;
var
objsym,
objsymend : TObjSymbol;
begin
while assigned(hp) do
begin
case hp.typ of
ait_align :
begin
if tai_align_abstract(hp).aligntype>1 then
begin
{ here we must determine the fillsize which is used in pass2 }
Tai_align_abstract(hp).fillsize:=align(ObjData.CurrObjSec.Size,Tai_align_abstract(hp).aligntype)-
ObjData.CurrObjSec.Size;
ObjData.alloc(Tai_align_abstract(hp).fillsize);
end;
end;
ait_datablock :
begin
if (oso_data in ObjData.CurrObjSec.secoptions) then
Message(asmw_e_alloc_data_only_in_bss);
{$ifdef USE_COMM_IN_BSS}
if writingpackages and
Tai_datablock(hp).is_global then
begin
objsym:=ObjData.SymbolDefine(Tai_datablock(hp).sym);
objsym.size:=Tai_datablock(hp).size;
objsym.bind:=AB_COMMON;
objsym.alignment:=needtowritealignmentalsoforELF;
end
else
{$endif USE_COMM_IN_BSS}
begin
ObjData.allocalign(used_align(size_2_align(Tai_datablock(hp).size),0,ObjData.CurrObjSec.secalign));
objsym:=ObjData.SymbolDefine(Tai_datablock(hp).sym);
objsym.size:=Tai_datablock(hp).size;
ObjData.alloc(Tai_datablock(hp).size);
end;
end;
ait_real_80bit :
ObjData.alloc(tai_real_80bit(hp).savesize);
ait_real_64bit :
ObjData.alloc(8);
ait_real_32bit :
ObjData.alloc(4);
ait_comp_64bit :
ObjData.alloc(8);
ait_const:
begin
{ Recalculate relative symbols }
if assigned(tai_const(hp).sym) and
assigned(tai_const(hp).endsym) then
begin
objsym:=Objdata.SymbolRef(tai_const(hp).sym);
objsymend:=Objdata.SymbolRef(tai_const(hp).endsym);
if objsymend.objsection<>objsym.objsection then
begin
if (Tai_const(hp).consttype in [aitconst_uleb128bit,aitconst_sleb128bit]) or
(objsym.objsection<>ObjData.CurrObjSec) then
internalerror(200905042);
end
else
Tai_const(hp).value:=objsymend.address-objsym.address+Tai_const(hp).symofs;
end;
ObjData.alloc(tai_const(hp).size);
end;
ait_section:
begin
{ use cached value }
ObjData.setsection(Tai_section(hp).sec);
end;
ait_stab :
begin
if assigned(Tai_stab(hp).str) then
WriteStab(Tai_stab(hp).str);
end;
ait_symbol :
ObjData.SymbolDefine(Tai_symbol(hp).sym);
ait_symbol_end :
begin
objsym:=ObjData.SymbolRef(Tai_symbol_end(hp).sym);
objsym.size:=ObjData.CurrObjSec.Size-objsym.offset;
end;
ait_label :
ObjData.SymbolDefine(Tai_label(hp).labsym);
ait_string :
ObjData.alloc(Tai_string(hp).len);
ait_instruction :
ObjData.alloc(Taicpu(hp).Pass1(ObjData));
ait_cutobject :
if SmartAsm then
break;
ait_directive :
begin
case tai_directive(hp).directive of
asd_indirect_symbol:
if tai_directive(hp).name='' then
Internalerror(2009101103)
else if not SetIndirectToSymbol(Tai(hp.Previous), tai_directive(hp).name) then
Internalerror(2009101102);
asd_lazy_reference:
{ handled in TreePass0 }
;
asd_reference:
{ ignore for now, but should be added}
;
else
internalerror(2010011102);
end;
end;
end;
hp:=Tai(hp.next);
end;
TreePass1:=hp;
end;
function TInternalAssembler.TreePass2(hp:Tai):Tai;
var
fillbuffer : tfillbuffer;
{$ifdef x86}
co : comp;
{$endif x86}
leblen : byte;
lebbuf : array[0..63] of byte;
objsym,
objsymend : TObjSymbol;
zerobuf : array[0..63] of byte;
relative_reloc: boolean;
begin
fillchar(zerobuf,sizeof(zerobuf),0);
fillchar(objsym,sizeof(objsym),0);
fillchar(objsymend,sizeof(objsymend),0);
{ main loop }
while assigned(hp) do
begin
case hp.typ of
ait_align :
begin
if tai_align_abstract(hp).aligntype>ObjData.CurrObjSec.secalign then
InternalError(2012072301);
if oso_data in ObjData.CurrObjSec.secoptions then
ObjData.writebytes(Tai_align_abstract(hp).calculatefillbuf(fillbuffer,oso_executable in ObjData.CurrObjSec.secoptions)^,
Tai_align_abstract(hp).fillsize)
else
ObjData.alloc(Tai_align_abstract(hp).fillsize);
end;
ait_section :
begin
{ use cached value }
ObjData.setsection(Tai_section(hp).sec);
end;
ait_symbol :
begin
ObjOutput.exportsymbol(ObjData.SymbolRef(Tai_symbol(hp).sym));
end;
ait_symbol_end :
begin
{ recalculate size, as some preceding instructions
could have been changed to smaller size }
objsym:=ObjData.SymbolRef(Tai_symbol_end(hp).sym);
objsym.size:=ObjData.CurrObjSec.Size-objsym.offset;
end;
ait_datablock :
begin
ObjOutput.exportsymbol(ObjData.SymbolRef(Tai_datablock(hp).sym));
{$ifdef USE_COMM_IN_BSS}
if not(writingpackages and
Tai_datablock(hp).is_global) then
{$endif USE_COMM_IN_BSS}
begin
ObjData.allocalign(used_align(size_2_align(Tai_datablock(hp).size),0,ObjData.CurrObjSec.secalign));
ObjData.alloc(Tai_datablock(hp).size);
end;
end;
ait_real_80bit :
begin
ObjData.writebytes(Tai_real_80bit(hp).value,10);
ObjData.writebytes(zerobuf,Tai_real_80bit(hp).savesize-10);
end;
ait_real_64bit :
ObjData.writebytes(Tai_real_64bit(hp).value,8);
ait_real_32bit :
ObjData.writebytes(Tai_real_32bit(hp).value,4);
ait_comp_64bit :
begin
{$ifdef x86}
co:=comp(Tai_comp_64bit(hp).value);
ObjData.writebytes(co,8);
{$endif x86}
end;
ait_string :
ObjData.writebytes(Tai_string(hp).str^,Tai_string(hp).len);
ait_const :
begin
{ Recalculate relative symbols, addresses of forward references
can be changed in treepass1 }
relative_reloc:=false;
if assigned(tai_const(hp).sym) and
assigned(tai_const(hp).endsym) then
begin
objsym:=Objdata.SymbolRef(tai_const(hp).sym);
objsymend:=Objdata.SymbolRef(tai_const(hp).endsym);
relative_reloc:=(objsym.objsection<>objsymend.objsection);
Tai_const(hp).value:=objsymend.address-objsym.address+Tai_const(hp).symofs;
end;
case tai_const(hp).consttype of
aitconst_64bit,
aitconst_32bit,
aitconst_16bit,
aitconst_64bit_unaligned,
aitconst_32bit_unaligned,
aitconst_16bit_unaligned,
aitconst_8bit :
begin
if assigned(tai_const(hp).sym) and
not assigned(tai_const(hp).endsym) then
ObjData.writereloc(Tai_const(hp).symofs,tai_const(hp).size,Objdata.SymbolRef(tai_const(hp).sym),RELOC_ABSOLUTE)
else if relative_reloc then
ObjData.writereloc(ObjData.CurrObjSec.size+tai_const(hp).size-objsym.address+tai_const(hp).symofs,tai_const(hp).size,objsymend,RELOC_RELATIVE)
else
ObjData.writebytes(Tai_const(hp).value,tai_const(hp).size);
end;
aitconst_rva_symbol :
begin
{ PE32+? }
if target_info.system=system_x86_64_win64 then
ObjData.writereloc(Tai_const(hp).symofs,sizeof(longint),Objdata.SymbolRef(tai_const(hp).sym),RELOC_RVA)
else
ObjData.writereloc(Tai_const(hp).symofs,sizeof(pint),Objdata.SymbolRef(tai_const(hp).sym),RELOC_RVA);
end;
aitconst_secrel32_symbol :
begin
{ Required for DWARF2 support under Windows }
ObjData.writereloc(Tai_const(hp).symofs,sizeof(longint),Objdata.SymbolRef(tai_const(hp).sym),RELOC_SECREL32);
end;
aitconst_gotoff_symbol:
ObjData.writereloc(Tai_const(hp).symofs,sizeof(longint),Objdata.SymbolRef(tai_const(hp).sym),RELOC_GOTOFF);
aitconst_uleb128bit,
aitconst_sleb128bit :
begin
if tai_const(hp).consttype=aitconst_uleb128bit then
leblen:=EncodeUleb128(qword(Tai_const(hp).value),lebbuf)
else
leblen:=EncodeSleb128(Tai_const(hp).value,lebbuf);
if leblen<>tai_const(hp).size then
internalerror(200709271);
ObjData.writebytes(lebbuf,leblen);
end;
aitconst_darwin_dwarf_delta32,
aitconst_darwin_dwarf_delta64:
ObjData.writebytes(Tai_const(hp).value,tai_const(hp).size);
else
internalerror(200603254);
end;
end;
ait_label :
begin
{ exporting shouldn't be necessary as labels are local,
but it's better to be on the safe side (PFV) }
ObjOutput.exportsymbol(ObjData.SymbolRef(Tai_label(hp).labsym));
end;
ait_instruction :
Taicpu(hp).Pass2(ObjData);
ait_stab :
WriteStab(Tai_stab(hp).str);
ait_function_name,
ait_force_line : ;
ait_cutobject :
if SmartAsm then
break;
{$ifndef DISABLE_WIN64_SEH}
ait_seh_directive :
tai_seh_directive(hp).generate_code(objdata);
{$endif DISABLE_WIN64_SEH}
end;
hp:=Tai(hp.next);
end;
TreePass2:=hp;
end;
procedure TInternalAssembler.writetree;
label
doexit;
var
hp : Tai;
ObjWriter : TObjectWriter;
begin
ObjWriter:=TObjectwriter.create;
ObjOutput:=CObjOutput.Create(ObjWriter);
ObjData:=ObjOutput.newObjData(ObjFileName);
{ Pass 0 }
ObjData.currpass:=0;
ObjData.createsection(sec_code);
ObjData.beforealloc;
{ start with list 1 }
currlistidx:=1;
currlist:=list[currlistidx];
hp:=Tai(currList.first);
while assigned(hp) do
begin
hp:=TreePass0(hp);
MaybeNextList(hp);
end;
ObjData.afteralloc;
{ leave if errors have occured }
if errorcount>0 then
goto doexit;
{ Pass 1 }
ObjData.currpass:=1;
ObjData.resetsections;
ObjData.beforealloc;
ObjData.createsection(sec_code);
{ start with list 1 }
currlistidx:=1;
currlist:=list[currlistidx];
hp:=Tai(currList.first);
while assigned(hp) do
begin
hp:=TreePass1(hp);
MaybeNextList(hp);
end;
ObjData.createsection(sec_code);
ObjData.afteralloc;
{ leave if errors have occured }
if errorcount>0 then
goto doexit;
{ Pass 2 }
ObjData.currpass:=2;
ObjData.resetsections;
ObjData.beforewrite;
ObjData.createsection(sec_code);
{ start with list 1 }
currlistidx:=1;
currlist:=list[currlistidx];
hp:=Tai(currList.first);
while assigned(hp) do
begin
hp:=TreePass2(hp);
MaybeNextList(hp);
end;
ObjData.createsection(sec_code);
ObjData.afterwrite;
{ don't write the .o file if errors have occured }
if errorcount=0 then
begin
{ write objectfile }
ObjOutput.startobjectfile(ObjFileName);
ObjOutput.writeobjectfile(ObjData);
end;
doexit:
{ Cleanup }
ObjData.free;
ObjData:=nil;
ObjWriter.free;
end;
procedure TInternalAssembler.writetreesmart;
var
hp : Tai;
startsectype : TAsmSectiontype;
place: tcutplace;
ObjWriter : TObjectWriter;
begin
if not(cs_asm_leave in current_settings.globalswitches) then
ObjWriter:=TARObjectWriter.create(current_module.staticlibfilename)
else
ObjWriter:=TObjectwriter.create;
NextSmartName(cut_normal);
ObjOutput:=CObjOutput.Create(ObjWriter);
startsectype:=sec_code;
{ start with list 1 }
currlistidx:=1;
currlist:=list[currlistidx];
hp:=Tai(currList.first);
while assigned(hp) do
begin
ObjData:=ObjOutput.newObjData(ObjFileName);
{ Pass 0 }
ObjData.currpass:=0;
ObjData.resetsections;
ObjData.beforealloc;
ObjData.createsection(startsectype);
TreePass0(hp);
ObjData.afteralloc;
{ leave if errors have occured }
if errorcount>0 then
break;
{ Pass 1 }
ObjData.currpass:=1;
ObjData.resetsections;
ObjData.beforealloc;
ObjData.createsection(startsectype);
TreePass1(hp);
ObjData.afteralloc;
{ leave if errors have occured }
if errorcount>0 then
break;
{ Pass 2 }
ObjData.currpass:=2;
ObjOutput.startobjectfile(ObjFileName);
ObjData.resetsections;
ObjData.beforewrite;
ObjData.createsection(startsectype);
hp:=TreePass2(hp);
ObjData.afterwrite;
{ leave if errors have occured }
if errorcount>0 then
break;
{ write the current objectfile }
ObjOutput.writeobjectfile(ObjData);
ObjData.free;
ObjData:=nil;
{ end of lists? }
if not MaybeNextList(hp) then
break;
{ we will start a new objectfile so reset everything }
{ The place can still change in the next while loop, so don't init }
{ the writer yet (JM) }
if (hp.typ=ait_cutobject) then
place := Tai_cutobject(hp).place
else
place := cut_normal;
{ avoid empty files }
startsectype:=sec_code;
while assigned(hp) and
(Tai(hp).typ in [ait_marker,ait_comment,ait_section,ait_cutobject]) do
begin
if Tai(hp).typ=ait_section then
startsectype:=Tai_section(hp).sectype;
if (Tai(hp).typ=ait_cutobject) then
place:=Tai_cutobject(hp).place;
hp:=Tai(hp.next);
end;
if not MaybeNextList(hp) then
break;
{ start next objectfile }
NextSmartName(place);
end;
ObjData.free;
ObjData:=nil;
ObjWriter.free;
end;
procedure TInternalAssembler.MakeObject;
var to_do:set of TasmlistType;
i:TasmlistType;
procedure addlist(p:TAsmList);
begin
inc(lists);
list[lists]:=p;
end;
begin
to_do:=[low(Tasmlisttype)..high(Tasmlisttype)];
if usedeffileforexports then
exclude(to_do,al_exports);
if not(tf_section_threadvars in target_info.flags) then
exclude(to_do,al_threadvars);
for i:=low(TasmlistType) to high(TasmlistType) do
if (i in to_do) and (current_asmdata.asmlists[i]<>nil) then
addlist(current_asmdata.asmlists[i]);
if SmartAsm then
writetreesmart
else
writetree;
end;
{*****************************************************************************
Generate Assembler Files Main Procedure
*****************************************************************************}
Procedure GenerateAsm(smart:boolean);
var
a : TAssembler;
begin
if not assigned(CAssembler[target_asm.id]) then
Message(asmw_f_assembler_output_not_supported);
a:=CAssembler[target_asm.id].Create(smart);
a.MakeObject;
a.Free;
end;
Procedure OnlyAsm;
var
a : TExternalAssembler;
begin
a:=TExternalAssembler.Create(false);
a.DoAssemble;
a.Free;
end;
{*****************************************************************************
Init/Done
*****************************************************************************}
procedure RegisterAssembler(const r:tasminfo;c:TAssemblerClass);
var
t : tasm;
begin
t:=r.id;
if assigned(asminfos[t]) then
writeln('Warning: Assembler is already registered!')
else
Getmem(asminfos[t],sizeof(tasminfo));
asminfos[t]^:=r;
CAssembler[t]:=c;
end;
end.