gcc/testsuite/gcc.c-torture/execute/pr59643.c

   1 /* PR tree-optimization/59643 */
   2
   3 #define N 32
   4
   5 __attribute__((noinline, noclone)) void
   6 foo (double *a, double *b, double *c, double d, double e, int n)
   7 {
   8   int i;
   9   for (i = 1; i < n - 1; i++)
  10     a[i] = d * (b[i] + c[i] + a[i - 1] + a[i + 1]) + e * a[i];
  11 }
  12
  13 double expected[] = {
  14   0.0, 10.0, 44.0, 110.0, 232.0, 490.0, 1020.0, 2078.0, 4152.0, 8314.0,
  15   16652.0, 33326.0, 66664.0, 133354.0, 266748.0, 533534.0, 1067064.0,
  16   2134138.0, 4268300.0, 8536622.0, 17073256.0, 34146538.0, 68293116.0,
  17   136586270.0, 273172536.0, 546345082.0, 1092690188.0, 2185380398.0,
  18   4370760808.0, 8741521642.0, 17483043324.0, 6.0
  19 };
  20
  21 int
  22 main ()
  23 {
  24   int i;
  25   double a[N], b[N], c[N];
  26   if (__DBL_MANT_DIG__ <= 35)
  27     return 0;
  28   for (i = 0; i < N; i++)
  29     {
  30       a[i] = (i & 3) * 2.0;
  31       b[i] = (i & 7) - 4;
  32       c[i] = i & 7;
  33     }
  34   foo (a, b, c, 2.0, 3.0, N);
  35   for (i = 0; i < N; i++)
  36     if (a[i] != expected[i])
  37       __builtin_abort ();
  38   return 0;
  39 }