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/*****************************************************************
 *
 *               The Compcert verified compiler
 *
 *           Xavier Leroy, INRIA Paris-Rocquencourt
 *
 * Copyright (c) 2013 Institut National de Recherche en Informatique et
 *  en Automatique.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the <organization> nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT
 * HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 **********************************************************************/

/* Helper functions for 64-bit integer arithmetic. Reference C implementation */

#include "i64.h"

/* Signed division */

signed long long i64_sdiv(signed long long n, signed long long d)
{
  unsigned long long un, ud, uq, ur;
  int nh = n >> 32, dh = d >> 32;
  /* Take absolute values of n and d */
  un = nh < 0 ? -n : n;
  ud = dh < 0 ? -d : d;
  uq = i64_udivmod(un, ud, &ur);
  /* Apply sign to quotient */
  return (nh ^ dh) < 0 ? -uq : uq;
}