gcc/testsuite/gcc.dg/vect/vect-recurr-6.c

   1 /* { dg-require-effective-target vect_int } */
   2 /* { dg-require-effective-target vect_perm } */
   3
   4 #include "tree-vect.h"
   5
   6 void __attribute__((noipa))
   7 foo (int * __restrict__ a, int * __restrict__ b, int * __restrict__ c, int n)
   8 {
   9   int t = *c;
  10   for (int i = 0; i < n; ++i)
  11     {
  12       b[i] = a[i] - t;
  13       t = a[i];
  14     }
  15 }
  16
  17 int a[64], b[64];
  18
  19 int
  20 main ()
  21 {
  22   check_vect ();
  23   for (int i = 0; i < 64; ++i)
  24     {
  25       a[i] = i;
  26       __asm__ volatile ("" ::: "memory");
  27     }
  28   int c = 7;
  29   foo (a, b, &c, 63);
  30 #pragma GCC novector
  31   for (int i = 1; i < 63; ++i)
  32     if (b[i] != a[i] - a[i-1])
  33       abort ();
  34   if (b[0] != -7)
  35     abort ();
  36   return 0;
  37 }
  38
  39 /* ???  We miss epilogue handling for first order recurrences.  */
  40 /* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" { target vect_fully_masked } } } */