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