gcc/testsuite/gcc.dg/store-motion-fgcse-sm.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -ftree-pre -fno-tree-loop-im -fgcse-sm -fdump-rtl-store_motion" } */
   3
   4 /* tree-pre moves the *sum load out of the loop.  ftree-loop-im moves the *sum
   5    store out of the loop, so we disable it, to allow fgcse-sm to do it
   6    instead.  */
   7
   8 #include <stdlib.h>
   9
  10 void __attribute__((noinline))
  11 f (unsigned int *__restrict__ a, unsigned int *__restrict__ sum, unsigned int n)
  12 {
  13   unsigned int i;
  14   for (i = 0; i < n; ++i)
  15     *sum += a[i];
  16 }
  17
  18 int
  19 main ()
  20 {
  21   unsigned int a[] = { 1, 10, 100 };
  22   unsigned sum = 1000;
  23
  24   f (a, &sum, 3);
  25   if (sum != 1111)
  26     abort ();
  27
  28   return 0;
  29 }
  30
  31 /* Check that -fgcse-sm did something for f.  */
  32 /* { dg-final { scan-rtl-dump "STORE_MOTION of f, .* basic blocks, 1 insns deleted, 1 insns created" "store_motion" } } */
  33