fpc/rtl/i386/cpu.pp
1998-03-25 11:18:12 +00:00

111 lines
2.8 KiB
ObjectPascal

{
$Id$
This file is part of the Free Pascal run time library.
Copyright (c) 1993,98 by Florian Klaempfl,
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.
**********************************************************************}
{ this unit contains some routines to get informations about the
processor
}
unit cpu;
{$I386_INTEL}
interface
{ returns true, if the processor supports the cpuid instruction }
function cpuid_support : boolean;
{ returns true, if floating point is done by an emulator }
function floating_point_emulation : boolean;
{ returns the contents of the cr0 register }
function cr0 : longint;
implementation
function cpuid_support : boolean;assembler;
{
Check if the ID-flag can be changed, if changed then CpuID is supported.
Tested under go32v1 and Linux on c6x86 with CpuID enabled and disabled (Syn)
}
asm
pushf
pushf
pop eax
mov ebx,eax
xor eax,200000h
push eax
popf
pushf
pop eax
popf
and eax,200000h
and ebx,200000h
cmp eax,ebx
setnz al
end;
function cr0 : longint;assembler;
asm
{ mov eax,cr0 }
end;
function floating_point_emulation : boolean;
begin
{!!!! I don't know currently the position of the EM flag }
floating_point_emulation:=(cr0 and $0)<>0;
end;
end.
{
$Log$
Revision 1.1 1998-03-25 11:18:42 root
Initial revision
Revision 1.6 1998/03/03 23:20:14 florian
* mov eax,cr0 isn't yet recognized by the asm parser, removed
Revision 1.5 1998/03/03 22:47:00 florian
* small problems fixed
Revision 1.4 1998/02/04 23:00:58 florian
- mmx stuff moved to mmx unit
Revision 1.3 1998/01/26 11:59:17 michael
+ Added log at the end
Working file: rtl/i386/cpu.pp
description:
----------------------------
revision 1.2
date: 1997/12/01 12:34:37; author: michael; state: Exp; lines: +12 -6
+ added copyright reference in header.
----------------------------
revision 1.1
date: 1997/11/27 22:49:04; author: florian; state: Exp;
- CPU.PP added
- some bugs in DOS fixed (especially for go32v1)
- the win32 system unit is now compilable
=============================================================================
History:
6th november 1997:
+ inital version (FK)
27th november 1997:
+ cpuid_support, thanks to synopsis (FK)
}