old-autovect-branch/gcc/testsuite/gcc.c-torture/execute/loop-ivopts-2.c

   1 /* PR rtl-optimization/20290  */
   2
   3 /* We used to mis-optimize the second loop in main on at least ppc and
   4    arm, because tree loop would change the loop to something like:
   5
   6   ivtmp.65 = &l[i];
   7   ivtmp.16 = 113;
   8   goto <bb 4> (<L4>);
   9
  10 <L3>:;
  11   *(ivtmp.65 + 4294967292B) = 9;
  12   i = i + 1;
  13
  14 <L4>:;
  15   ivtmp.16 = ivtmp.16 - 1;
  16   ivtmp.65 = ivtmp.65 + 4B;
  17   if (ivtmp.16 != 0) goto <L3>;
  18
  19   We used to consider the increment of i as executed in every
  20   iteration, so we'd miscompute the final value.  */
  21
  22 extern void abort (void);
  23
  24 void
  25 check (unsigned int *l)
  26 {
  27   int i;
  28   for (i = 0; i < 288; i++)
  29     if (l[i] != 7 + (i < 256 || i >= 280) + (i >= 144 && i < 256))
  30       abort ();
  31 }
  32
  33 int
  34 main (void)
  35 {
  36   int i;
  37   unsigned int l[288];
  38
  39   for (i = 0; i < 144; i++)
  40     l[i] = 8;
  41   for (; i < 256; i++)
  42     l[i] = 9;
  43   for (; i < 280; i++)
  44     l[i] = 7;
  45   for (; i < 288; i++)
  46     l[i] = 8;
  47   check (l);
  48   return 0;
  49 }
  50