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/* PR tree-optimization/47538 */

struct S

{

  double a, b, *c;

  unsigned long d;

};

__attribute__((noinline, noclone)) void

foo (struct S *x, const struct S *y)

{

  const unsigned long n = y->d + 1;

  const double m = 0.25 * (y->b - y->a);

  x->a = y->a;

  x->b = y->b;

  if (n == 1)

    {

      x->c[0] = 0.;

    }

  else if (n == 2)

    {

      x->c[1] = m * y->c[0];

      x->c[0] = 2.0 * x->c[1];

    }

  else

    {

      double o = 0.0, p = 1.0;

      unsigned long i;

      for (i = 1; i <= n - 2; i++)

        {

          x->c[i] = m * (y->c[i - 1] - y->c[i + 1]) / (double) i;

          o += p * x->c[i];

          p = -p;

        }

      x->c[n - 1] = m * y->c[n - 2] / (n - 1.0);

      o += p * x->c[n - 1];

      x->c[0] = 2.0 * o;

    }

}

int

main (void)

{

  struct S x, y;

  double c[4] = { 10, 20, 30, 40 }, d[4], e[4] = { 118, 118, 118, 118 };

  y.a = 10;

  y.b = 6;

  y.c = c;

  x.c = d;

  y.d = 3;

  __builtin_memcpy (d, e, sizeof d);

  foo (&x, &y);

  if (d[0] != 0 || d[1] != 20 || d[2] != 10 || d[3] != -10)

    __builtin_abort ();

  y.d = 2;

  __builtin_memcpy (d, e, sizeof d);

  foo (&x, &y);

  if (d[0] != 60 || d[1] != 20 || d[2] != -10 || d[3] != 118)

    __builtin_abort ();

  y.d = 1;

  __builtin_memcpy (d, e, sizeof d);

  foo (&x, &y);

  if (d[0] != -20 || d[1] != -10 || d[2] != 118 || d[3] != 118)

    __builtin_abort ();

  y.d = 0;

  __builtin_memcpy (d, e, sizeof d);

  foo (&x, &y);

  if (d[0] != 0 || d[1] != 118 || d[2] != 118 || d[3] != 118)

    __builtin_abort ();

  return 0;

}