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/* dsp.c */
/*  {{{
 *
 * Copyright (C) 2004 Nicolas Schodet
 *
 * 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 the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Contact :
 *        Web: http://perso.efrei.fr/~schodet/
 *      Email: <contact@ni.fr.eu.org>
 * }}} */
#include "dsp.h"

/* +AutoDec */
/* -AutoDec */

/* Add two signed words and saturate. */
inline int16_t
dsp_i16i16_add_sat (int16_t a, int16_t b)
{
    asm ("add %A0, %A1\n\t"
	 "adc %B0, %B1\n\t"
	 /* Branch if not V. */
	 "brvc 1f\n\t"
	 /* Load Max. */
	 "ldi %A0, 0xff\n\t"
	 "ldi %B0, 0x7f\n\t"
	 /* Branch if not S. */
	 "brlt 1f\n\t"
	 /* Load Min. */
	 "ldi %A0, 0x00\n\t"
	 "ldi %B0, 0x80\n\t"
    "1f" "\n\t"
	 : "=r" a : "0" a, "r" b);
    return a;
}

/* Multiply and saturate. */
inline int16_t
dsp_i16u8_mul_sat (int16_t a, uint8_t b)
{
    asm ("mul
}