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/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
Copyright (C) 2015-2019 GrangerHub

This file is part of Tremulous.

Tremulous 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 3 of the License,
or (at your option) any later version.

Tremulous 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 Tremulous; if not, see <https://www.gnu.org/licenses/>

===========================================================================
*/
//
// 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