Subversion Repositories openrisc_me

/* Test double on x86. */

/* { dg-do run } */

/* { dg-options -O2 } */

extern void abort (void);

static __inline  double

mypow (double __x, double __y)

{

  register double __value, __exponent;

  long __p = (long) __y;

  if (__y == (double) __p)

    {

      double __r = 1.0;

      if (__p == 0)

        return 1.0;

      if (__p < 0)

        {

          __p = -__p;

          __x = 1.0 / __x;

        }

      while (1)

        {

          if (__p & 1)

            __r *= __x;

          __p >>= 1;

          if (__p == 0)

            return __r;

          __x *= __x;

        }

    }

  __asm __volatile__

    ("fmul      %%st(1),%%st\n\t"       /* y * log2(x) */

     "fst       %%st(1)\n\t"

     "frndint\n\t"                      /* int(y * log2(x)) */

     "fxch  %%st(1)\n\t"

     "fsub      %%st(1),%%st\n\t"       /* fract(y * log2(x)) */

     "f2xm1\n\t"                        /* 2^(fract(y * log2(x))) - 1 */

     : "=t" (__value), "=u" (__exponent) :  "0" (__x), "1" (__y));

  __value += 1.0;

  __asm __volatile__

    ("fscale"

     : "=t" (__value) : "0" (__value), "u" (__exponent));

  return __value;

}

const double E1 = 2.71828182845904523536028747135;

double fact (double x)

{

  double corr;

  corr = 1.0;

  return corr * mypow(x/E1, x);

}

int main ()

{

  double y, z;

  y = fact (46.2);

  z = mypow (46.2/E1, 46.2);

#if 0

  printf ("%26.19e, %26.19e\n", y, z);

#endif

  if (y > z)

    y -= z;

  else

    y = z - y;

  y /= z;

  if (y > 0.1)

    abort ();

  return 0;

}