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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