fpc/rtl/dos/go32v2/emu387.pp
peter aaa3da644b * emu387 doesn't uses dos anymore (getenv copied local)
* makefile compilation order changed
1998-03-26 12:23:17 +00:00

291 lines
7.8 KiB
ObjectPascal

{
$Id$
This file is part of the Free Pascal run time library.
Copyright (c) 1993,97 by Pierre Muller,
member of the Free Pascal development team.
See the file COPYING.FPC, included in this distribution,
for details about the copyright.
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.
**********************************************************************}
{ Translated to FPK pascal by Pierre Muller,
without changing the fpu.s file }
{
/* Copyright (C) 1994, 1995 Charles Sandmann (sandmann@clio.rice.edu)
* FPU setup and emulation hooks for DJGPP V2.0
* This file maybe freely distributed, no warranty. */
this file has been translated from
npxsetup.c }
unit emu387;
interface
procedure npxsetup(prog_name : string);
implementation
uses dxeload, dpmiexcp, strings;
type
emu_entry_type = function(exc : pexception_state) : longint;
var
_emu_entry : emu_entry_type;
procedure _control87(mask1,mask2 : word);
begin
{/* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */}
{ from file cntrl87.s in src/libc/pc_hw/fpu }
asm
{ make room on stack }
pushl %eax
fstcw (%esp)
fwait
popl %eax
andl $0xffff, %eax
{ OK; we have the old value ready }
movl mask2, %ecx
notl %ecx
andl %eax, %ecx /* the bits we want to keep */
movl mask2, %edx
andl mask1, %edx /* the bits we want to change */
orl %ecx, %edx /* the new value */
pushl %edx
fldcw (%esp)
popl %edx
end;
end;
{ the problem with the stack that is not cleared }
function emu_entry(exc : pexception_state) : longint;
begin
emu_entry:=_emu_entry(exc);
end;
function nofpsig( sig : longint) : longint;
var res : longint;
const
last_eip : longint = 0;
begin
{if last_eip=djgpp_exception_state^.__eip then
begin
writeln('emu call two times at same address');
dpmi_set_coprocessor_emulation(1);
_raise(SIGFPE);
exit(0);
end; }
last_eip:=djgpp_exception_state^.__eip;
res:=emu_entry(djgpp_exception_state);
if res<>0 then
begin
writeln('emu call failed. res = ',res);
dpmi_set_coprocessor_emulation(1);
_raise(SIGFPE);
exit(0);
end;
longjmp(pjmprec(djgpp_exception_state)^, djgpp_exception_state^.__eax);
nofpsig:=0;
end;
var
prev_exit : pointer;
procedure restore_DPMI_fpu_state;
begin
exitproc:=prev_exit;
dpmi_set_coprocessor_emulation(1);
writeln('Coprocessor restored ');
{/* Enable Coprocessor, no exceptions */}
end;
{ function _detect_80387 : boolean;[C];
not used because of the underscore problem }
{$L fpu.o }
function getenv(const envvar:string):string;
{ Copied here, preserves uses Dos (PFV) }
var
hp : ppchar;
hs,
_envvar : string;
eqpos,i : longint;
begin
_envvar:=upcase(envvar);
hp:=environ;
getenv:='';
while assigned(hp^) do
begin
hs:=strpas(hp^);
eqpos:=pos('=',hs);
if copy(hs,1,eqpos-1)=_envvar then
begin
getenv:=copy(hs,eqpos+1,255);
exit;
end;
hp:=hp+4;
end;
end;
procedure npxsetup(prog_name : string);
var
cp : string;
i : byte;
have_80387 : boolean;
emu_p : pointer;
const
veryfirst : boolean = True;
begin
cp:=getenv('387');
if (length(cp)>0) and (upcase(cp[1])='N') then
have_80387:=False
else
begin
dpmi_set_coprocessor_emulation(1);
asm
call __detect_80387
movb %al,have_80387
end;
end;
if (length(cp)>0) and (upcase(cp[1])='Q') then
begin
if not have_80387 then
write(stderr,'No ');
writeln(stderr,'80387 detected.');
end;
if have_80387 then
{/* mask all exceptions, except invalid operation */}
_control87($033e, $ffff)
else
begin
{/* Flags value 3 means coprocessor emulation, exceptions to us */}
if (dpmi_set_coprocessor_emulation(3)<>0) then
begin
writeln(stderr,'Warning: Coprocessor not present and DPMI setup failed!');
writeln(stderr,' If application attempts floating operations system may hang!');
end
else
begin
cp:=getenv('EMU387');
if length(cp)=0 then
begin
for i:=length(prog_name) downto 1 do
if (prog_name[i]='\') or (prog_name[i]='/') then
break;
if i>1 then
cp:=copy(prog_name,1,i);
cp:=cp+'wmemu387.dxe';
end;
emu_p:=dxe_load(cp);
_emu_entry:=emu_entry_type(emu_p);
if (emu_p=nil) then
begin
writeln(cp+' load failed !');
halt;
end;
if veryfirst then
begin
veryfirst:=false;
prev_exit:=exitproc;
exitproc:=@restore_DPMI_fpu_state;
end;
signal(SIGNOFP,@nofpsig);
end;
end;
end;
begin
npxsetup(paramstr(0));
end.
{
$Log$
Revision 1.2 1998-03-26 12:23:17 peter
* emu387 doesn't uses dos anymore (getenv copied local)
* makefile compilation order changed
Revision 1.1.1.1 1998/03/25 11:18:42 root
* Restored version
Revision 1.6 1998/03/18 15:34:46 pierre
+ fpu state is restaured in excep_exit
less risk of problems
Revision 1.5 1998/02/05 17:24:09 pierre
* bug in assembler code
* changed default name to wmemu387.dxe
Revision 1.4 1998/02/05 17:04:59 pierre
* emulation is working with wmemu387.dxe
Revision 1.3 1998/01/26 11:57:34 michael
+ Added log at the end
Revision 1.2 1998/01/19 17:04:40 pierre
* bug in dxe loading corrected, emu still does not work !!
Revision 1.1 1998/01/16 16:53:15 pierre
emu387 is a program based on npxset from DJGPP
that loads the emu387.dxe if no FPU is present
or if the env var 387 is set to N
}
{
$Log$
Revision 1.2 1998-03-26 12:23:17 peter
* emu387 doesn't uses dos anymore (getenv copied local)
* makefile compilation order changed
Revision 1.1.1.1 1998/03/25 11:18:42 root
* Restored version
Revision 1.6 1998/03/18 15:34:46 pierre
+ fpu state is restaured in excep_exit
less risk of problems
Revision 1.5 1998/02/05 17:24:09 pierre
* bug in assembler code
* changed default name to wmemu387.dxe
Revision 1.4 1998/02/05 17:04:59 pierre
* emulation is working with wmemu387.dxe
Revision 1.3 1998/01/26 11:57:34 michael
+ Added log at the end
Working file: rtl/dos/go32v2/emu387.pp
description:
----------------------------
revision 1.2
date: 1998/01/19 17:04:40; author: pierre; state: Exp; lines: +11 -2
* bug in dxe loading corrected, emu still does not work !!
----------------------------
revision 1.1
date: 1998/01/16 16:53:15; author: pierre; state: Exp;
emu387 is a program based on npxset from DJGPP
that loads the emu387.dxe if no FPU is present
or if the env var 387 is set to N
=============================================================================
}