Subversion Repositories openrisc_2011-10-31

/*

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

 * 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__

        long int lround(double x)

#else

        long int lround(x)

        double x;

#endif

{

  __int32_t sign, exponent_less_1023;

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

  __uint32_t msw, lsw;

  long int result;

  EXTRACT_WORDS(msw, lsw, x);

  /* Extract sign. */

  sign = ((msw & 0x80000000) ? -1 : 1);

  /* Extract exponent field. */

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

  msw &= 0x000fffff;

  msw |= 0x00100000;

  if (exponent_less_1023 < 20)

    {

      if (exponent_less_1023 < 0)

        {

          if (exponent_less_1023 < -1)

            return 0;

          else

            return sign;

        }

      else

        {

          msw += 0x80000 >> exponent_less_1023;

          result = msw >> (20 - exponent_less_1023);

        }

    }

  else if (exponent_less_1023 < (8 * sizeof (long int)) - 1)

    {

      if (exponent_less_1023 >= 52)

        result = ((long int) msw << (exponent_less_1023 - 20)) | (lsw << (exponent_less_1023 - 52));

      else

        {

          unsigned int tmp = lsw + (0x80000000 >> (exponent_less_1023 - 20));

          if (tmp < lsw)

            ++msw;

          result = ((long int) msw << (exponent_less_1023 - 20)) | (tmp >> (52 - exponent_less_1023));

        }

    }

  else

    /* Result is too large to be represented by a long int. */

    return (long int)x;

  return sign * result;

}

#endif /* _DOUBLE_IS_32BITS */