gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-10.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -floop-interchange -fdump-tree-linterchange-details" } */
   3 /* { dg-skip-if "too big data segment" { visium-*-* } } */
   4
   5 #define M 256
   6 int a[M][M], b[M][M];
   7 int __attribute__((noinline))
   8 double_reduc (int n)
   9 {
  10   int sum = 0;
  11   for (int j = 0; j < n; j++)
  12     {
  13       for (int i = 0; i < n; i++)
  14         sum = sum + a[i][j]*b[i][j];
  15     }
  16   return sum;
  17 }
  18
  19 extern void abort ();
  20
  21 static void __attribute__((noinline))
  22 init (int i)
  23 {
  24   for (int j = 0; j < M; j++)
  25     {
  26       a[i][j] = i;
  27       b[i][j] = j;
  28     }
  29 }
  30
  31 int main (void)
  32 {
  33   for (int i = 0; i < M; ++i)
  34     init (i);
  35
  36   int sum = double_reduc (M);
  37
  38   if (sum != 1065369600)
  39     abort ();
  40
  41   return 0;
  42 }
  43
  44 /* { dg-final { scan-tree-dump-times "Loop_pair<outer:., inner:.> is interchanged" 1 "linterchange" } } */