gcc/testsuite/gcc.dg/vect/vect-recurr-3.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, signed char * __restrict__ b, int * __restrict__ c)
   8 {
   9   int t = *c;
  10   for (int i = 0; i < 64; ++i)
  11     {
  12       b[i] = a[i] - t;
  13       t = a[i];
  14     }
  15 }
  16
  17 int a[64];
  18 signed char b[64];
  19
  20 int
  21 main ()
  22 {
  23   check_vect ();
  24   for (int i = 0; i < 64; ++i)
  25     {
  26       a[i] = i;
  27       __asm__ volatile ("" ::: "memory");
  28     }
  29   int c = 7;
  30   foo (a, b, &c);
  31 #pragma GCC novector
  32   for (int i = 1; i < 64; ++i)
  33     if (b[i] != a[i] - a[i-1])
  34       abort ();
  35   if (b[0] != -7)
  36     abort ();
  37   return 0;
  38 }
  39
  40 /* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" } } */