gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-1.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -floop-interchange -fassociative-math -fno-signed-zeros -fno-trapping-math -fdump-tree-linterchange-details" } */
   3
   4 /* Copied from graphite/interchange-4.c */
   5
   6 #define DEBUG 0
   7 #if DEBUG
   8 #include <stdio.h>
   9 #endif
  10
  11 double u[1782225];
  12
  13 static int __attribute__((noinline))
  14 foo (int N, int *res)
  15 {
  16   int i, j;
  17   double sum = 0;
  18   for (i = 0; i < N; i++)
  19     for (j = 0; j < N; j++)
  20       sum = sum + u[i + 1335 * j];
  21
  22   for (i = 0; i < N; i++)
  23     u[1336 * i] *= 2;
  24
  25   *res = sum + N + u[1336 * 2] + u[1336];
  26 }
  27
  28 extern void abort ();
  29
  30 int
  31 main (void)
  32 {
  33   int i, j, res;
  34
  35   for (i = 0; i < 1782225; i++)
  36     u[i] = 2;
  37
  38   foo (1335, &res);
  39
  40 #if DEBUG
  41   fprintf (stderr, "res = %d \n", res);
  42 #endif
  43
  44   if (res != 3565793)
  45     abort ();
  46
  47   return 0;
  48 }
  49
  50 /* { dg-final { scan-tree-dump-times "Loop_pair<outer:., inner:.> is interchanged" 1 "linterchange"} } */