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/*
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 * libmad - MPEG audio decoder library
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 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 *
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 * $Id: fixed.c,v 1.13 2004/01/23 09:41:32 rob Exp $
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 */
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# ifdef HAVE_CONFIG_H
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#  include "config.h"
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# endif
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# include "global.h"
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# include "fixed.h"
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/*
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 * NAME:	fixed->abs()
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 * DESCRIPTION:	return absolute value of a fixed-point number
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 */
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mad_fixed_t mad_f_abs(mad_fixed_t x)
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{
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  return x < 0 ? -x : x;
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}
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/*
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 * NAME:	fixed->div()
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 * DESCRIPTION:	perform division using fixed-point math
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 */
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mad_fixed_t mad_f_div(mad_fixed_t x, mad_fixed_t y)
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{
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  mad_fixed_t q, r;
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  unsigned int bits;
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  q = mad_f_abs(x / y);
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  if (x < 0) {
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    x = -x;
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    y = -y;
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  }
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  r = x % y;
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  if (y < 0) {
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    x = -x;
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    y = -y;
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  }
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  if (q > mad_f_intpart(MAD_F_MAX) &&
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      !(q == -mad_f_intpart(MAD_F_MIN) && r == 0 && (x < 0) != (y < 0)))
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    return 0;
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  for (bits = MAD_F_FRACBITS; bits && r; --bits) {
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    q <<= 1, r <<= 1;
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    if (r >= y)
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      r -= y, ++q;
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  }
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  /* round */
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  if (2 * r >= y)
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    ++q;
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  /* fix sign */
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  if ((x < 0) != (y < 0))
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    q = -q;
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  return q << bits;
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}