gcc/testsuite/gcc.dg/vect/bb-slp-41.c

   1 /* { dg-require-effective-target vect_int } */
   2
   3 #define ARR_SIZE 1000
   4
   5 void __attribute__((optimize (0)))
   6 foo (int *a, int *b)
   7 {
   8   int i;
   9   for (i = 0; i < (ARR_SIZE - 2); ++i)
  10     a[i] = b[0] + b[1] + b[i+1] + b[i+2];
  11 }
  12
  13 /* Disable pre-slp FRE to avoid unexpected SLP on the epilogue
  14    of the 1st loop.  */
  15 void __attribute__((optimize("-fno-tree-fre")))
  16 bar (int *a, int *b)
  17 {
  18   int i;
  19   for (i = 0; i < (ARR_SIZE - 2); ++i)
  20   {
  21     a[i] = b[0];
  22   }
  23   for (i = 0; i < (ARR_SIZE - 2); ++i)
  24   {
  25     a[i] = a[i] + b[1];
  26   }
  27   for (i = 0; i < (ARR_SIZE - 2); ++i)
  28   {
  29     a[i] = a[i] + b[i+1];
  30   }
  31   for (i = 0; i < (ARR_SIZE - 2); ++i)
  32   {
  33     a[i] = a[i] + b[i+2];
  34   }
  35 }
  36
  37 int main ()
  38 {
  39   int a1[ARR_SIZE];
  40   int a2[ARR_SIZE];
  41   int b[ARR_SIZE];
  42   int i;
  43
  44   for (i = 0; i < ARR_SIZE; i++)
  45   {
  46     a1[i] = 0;
  47     a2[i] = 0;
  48     b[i]  = i;
  49   }
  50
  51   foo (a1, b);
  52   bar (a2, b);
  53
  54   for (i = 0; i < ARR_SIZE; i++)
  55     if (a1[i] != a2[i])
  56       return 1;
  57
  58   return 0;
  59
  60 }
  61 /* { dg-final { scan-tree-dump-not "vectorizing stmts using SLP" "slp1" } } */