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/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code 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.

Quake III Arena source code 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 Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

//
// Sys_SnapVector NASM code (Andrew Henderson)
// See win32/win_shared.c for the Win32 equivalent
// This code is provided to ensure that the
//  rounding behavior (and, if necessary, the
//  precision) of DLL and QVM code are identical
//  e.g. for network-visible operations.
// See ftol.nasm for operations on a single float,
//  as used in compiled VM and DLL code that does
//  not use this system trap.
//

// 23/09/05 Ported to gas by intel2gas, best supporting actor Tim Angus
// <tim@ngus.net>

#include "qasm.h"

#if id386
.data

fpucw:  .long   0
cw037F: .long   0x037F

.text

// void Sys_SnapVector( float *v )
.globl C(Sys_SnapVector)
C(Sys_SnapVector):
        pushl   %eax
        pushl   %ebp
        movl    %esp,%ebp

        fnstcw  fpucw
        movl    12(%ebp),%eax
        fldcw   cw037F
        flds    (%eax)
        fistpl  (%eax)
        fildl   (%eax)
        fstps   (%eax)
        flds    4(%eax)
        fistpl  4(%eax)
        fildl   4(%eax)
        fstps   4(%eax)
        flds    8(%eax)
        fistpl  8(%eax)
        fildl   8(%eax)
        fstps   8(%eax)
        fldcw   fpucw

        popl %ebp
        popl %eax
        ret

// void Sys_SnapVectorCW( float *v, unsigned short int cw )
.globl C(Sys_SnapVectorCW)
C(Sys_SnapVectorCW):
        pushl   %eax
        pushl   %ebp
        movl    %esp,%ebp

        fnstcw  fpucw
        movl    12(%ebp),%eax
        fldcw   16(%ebp)
        flds    (%eax)
        fistpl  (%eax)
        fildl   (%eax)
        fstps   (%eax)
        flds    4(%eax)
        fistpl  4(%eax)
        fildl   4(%eax)
        fstps   4(%eax)
        flds    8(%eax)
        fistpl  8(%eax)
        fildl   8(%eax)
        fstps   8(%eax)
        fldcw   fpucw

        popl %ebp
        popl %eax
        ret
#endif