gcc/testsuite/gcc.dg/tree-ssa/pr21001.c

   1 /* PR tree-optimization/21001
   2    VRP did not insert ASSERT_EXPRs when the variable tested in a
   3    COND_EXPR is a single-use variable.  By propagating the definition
   4    of the single-use variable into the COND_EXPR, we can get useful
   5    range infomation out of the conditional.  */
   6
   7 /* { dg-do compile } */
   8 /* { dg-options "-O2 -fno-tree-dominator-opts -fdump-tree-vrp1-details" } */
   9
  10 int
  11 foo (int a)
  12 {
  13   int b = a != 0;
  14   if (b)
  15     if (a != 0)
  16       return 1;
  17   return 0;
  18 }
  19
  20 /* { dg-final { scan-tree-dump-times "Folding predicate" 1 "vrp1"} } */
  21 /* { dg-final { cleanup-tree-dump "vrp1" } } */