newtree/source/sys_dosa.S

122 lines
2 KiB
ArmAsm
Raw Normal View History

/*
sys_dosa.S
(description)
Copyright (C) 1996-1997 Id Software, Inc.
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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
$Id$
*/
// sys_dosa.s
// x86 assembly-language DOS-dependent routines.
#include "asm_i386.h"
#include "quakeasm.h"
.data
.align 4
fpenv:
.long 0, 0, 0, 0, 0, 0, 0, 0
.text
.globl C(MaskExceptions)
C(MaskExceptions):
fnstenv fpenv
orl $0x3F,fpenv
fldenv fpenv
ret
#if 0
.globl C(unmaskexceptions)
C(unmaskexceptions):
fnstenv fpenv
andl $0xFFFFFFE0,fpenv
fldenv fpenv
ret
#endif
.data
.align 4
.globl ceil_cw, single_cw, full_cw, cw, pushed_cw
ceil_cw: .long 0
single_cw: .long 0
full_cw: .long 0
cw: .long 0
pushed_cw: .long 0
.text
.globl C(Sys_LowFPPrecision)
C(Sys_LowFPPrecision):
fldcw single_cw
ret
.globl C(Sys_HighFPPrecision)
C(Sys_HighFPPrecision):
fldcw full_cw
ret
.globl C(Sys_PushFPCW_SetHigh)
C(Sys_PushFPCW_SetHigh):
fnstcw pushed_cw
fldcw full_cw
ret
.globl C(Sys_PopFPCW)
C(Sys_PopFPCW):
fldcw pushed_cw
ret
.globl C(Sys_SetFPCW)
C(Sys_SetFPCW):
fnstcw cw
movl cw,%eax
#if id386
andb $0xF0,%ah
orb $0x03,%ah // round mode, 64-bit precision
#endif
movl %eax,full_cw
#if id386
andb $0xF0,%ah
orb $0x0C,%ah // chop mode, single precision
#endif
movl %eax,single_cw
#if id386
andb $0xF0,%ah
orb $0x08,%ah // ceil mode, single precision
#endif
movl %eax,ceil_cw
ret