gcc/testsuite/gcc.dg/tree-ssa/vrp-loop-1.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-Os -fdump-tree-optimized" } */
   3 /* PR tree-optimization/110768 */
   4 /* The call to foo should be able to removed,
   5    The branch to unreachable is unreachable as
   6    VRP (ranger) figure out that c there can only
   7    be -20409 or 0. before r14-5109-ga291237b628f41
   8    ranger could not figure that out.  */
   9
  10
  11 void foo(void);
  12 static int a, b;
  13 int main() {
  14     {
  15         short c = 45127;
  16         signed char d;
  17         b = 0;
  18         for (; b <= 3; b++) {
  19             if (b) continue;
  20             d = 0;
  21             for (; d <= 100; d++) {
  22                 if (!(((c) >= -20409) && ((c) <= 1))) {
  23                     __builtin_unreachable();
  24                 }
  25                 if (~(0 == a) & 1) return b;
  26                 c = 0;
  27                 for (; c <= 0; c++) a = 3;
  28             }
  29         }
  30         foo();
  31     }
  32 }
  33
  34 /* { dg-final { scan-tree-dump-not "foo " "optimized" } } */