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/*

 * ====================================================

 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.

 *

 * Developed at SunPro, a Sun Microsystems, Inc. business.

 * Permission to use, copy, modify, and distribute this

 * software is freely granted, provided that this notice

 * is preserved.

 * ====================================================

 */

#include "fdlibm.h"

#ifndef _DOUBLE_IS_32BITS

#ifdef __STDC__

        double round(double x)

#else

        double round(x)

        double x;

#endif

{

  /* Most significant word, least significant word. */

  __int32_t msw, exponent_less_1023;

  __uint32_t lsw;

  EXTRACT_WORDS(msw, lsw, x);

  /* Extract exponent field. */

  exponent_less_1023 = ((msw & 0x7ff00000) >> 20) - 1023;

  if (exponent_less_1023 < 20)

    {

      if (exponent_less_1023 < 0)

        {

          msw &= 0x80000000;

          if (exponent_less_1023 == -1)

            /* Result is +1.0 or -1.0. */

            msw |= (1023 << 20);

          lsw = 0;

        }

      else

        {

          __uint32_t exponent_mask = 0x000fffff >> exponent_less_1023;

          if ((msw & exponent_mask) == 0 && lsw == 0)

            /* x in an integral value. */

            return x;

          msw += 0x00080000 >> exponent_less_1023;

          msw &= ~exponent_mask;

          lsw = 0;

        }

    }

  else if (exponent_less_1023 > 51)

    {

      if (exponent_less_1023 == 1024)

        /* x is NaN or infinite. */

        return x + x;

      else

        return x;

    }

  else

    {

      __uint32_t exponent_mask = 0xffffffff >> (exponent_less_1023 - 20);

      __uint32_t tmp;

      if ((lsw & exponent_mask) == 0)

        /* x is an integral value. */

        return x;

      tmp = lsw + (1 << (51 - exponent_less_1023));

      if (tmp < lsw)

        msw += 1;

      lsw = tmp;

      lsw &= ~exponent_mask;

    }

  INSERT_WORDS(x, msw, lsw);

  return x;

}

#endif /* _DOUBLE_IS_32BITS */