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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 Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
===========================================================================
*/
//
// math.s
// x86 assembly-language math routines.
#include "qasm.h"
#if id386
.text
// TODO: rounding needed?
// stack parameter offset
#define val 4
.globl C(Invert24To16)
C(Invert24To16):
movl val(%esp),%ecx
movl $0x100,%edx // 0x10000000000 as dividend
cmpl %edx,%ecx
jle LOutOfRange
subl %eax,%eax
divl %ecx
ret
LOutOfRange:
movl $0xFFFFFFFF,%eax
ret
#endif // id386
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