gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-3.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -floop-interchange -fdump-tree-linterchange-details" } */
   3
   4 /* Copied from graphite/interchange-6.c */
   5
   6 #define DEBUG 0
   7 #if DEBUG
   8 #include <stdio.h>
   9 #endif
  10
  11 #define N 100
  12 #define M 200
  13
  14 static int __attribute__((noinline))
  15 foo (int A[N][M])
  16 {
  17   int i, j;
  18
  19   /* This loop should be interchanged. */
  20   for(j = 0; j < M; j++)
  21     for(i = 0; i < N; i++)
  22       A[i][j] = A[i][j] + A[i][j];
  23
  24   return A[0][0] + A[N-1][M-1];
  25 }
  26
  27 extern void abort ();
  28
  29 static void __attribute__((noinline))
  30 init (int *arr, int i)
  31 {
  32   int j;
  33
  34   for (j = 0; j < M; j++)
  35     arr[j] = 2;
  36 }
  37
  38 int
  39 main (void)
  40 {
  41   int A[N][M];
  42   int i, j, res;
  43
  44   for (i = 0; i < N; i++)
  45     init (A[i], i);
  46
  47   res = foo (A);
  48
  49 #if DEBUG
  50   fprintf (stderr, "res = %d \n", res);
  51 #endif
  52
  53   if (res != 8)
  54     abort ();
  55
  56   return 0;
  57 }
  58
  59 /* { dg-final { scan-tree-dump-times "Loop_pair<outer:., inner:.> is interchanged" 1 "linterchange"} } */