gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-thread-12.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-dom2-details -w -fdisable-tree-thread1" } */
   3 typedef long unsigned int size_t;
   4 union tree_node;
   5 typedef union tree_node *tree;
   6 typedef union gimple_statement_d *gimple;
   7 typedef const union gimple_statement_d *const_gimple;
   8 union gimple_statement_d
   9 {
  10   unsigned num_ops;
  11   tree exp;
  12 };
  13 void gimple_call_arg (gimple, unsigned);
  14
  15 unsigned int x;
  16 static inline tree
  17 gimple_op (const_gimple gs, unsigned i)
  18 {
  19   if (!(i < gs->num_ops))
  20     __builtin_abort ();
  21   return gs->exp;
  22 }
  23
  24 unsigned char
  25 scan_function (gimple stmt)
  26 {
  27   unsigned i;
  28   for (i = 0; i < stmt->num_ops - 3 ; i++)
  29     gimple_call_arg (stmt, i);
  30   gimple_op (stmt, 1);
  31 }
  32
  33 /* The test which bypasses the loop is simplified prior to DOM to check
  34    that stmt->num_ops - 3 != 0.  When that test is false, we can derive
  35    a value for stmt->num_ops.  That in turn allows us to thread the jump
  36    for the conditional at the start of the call to gimple_op.  */
  37 /* { dg-final { scan-tree-dump-times "Threaded" 1 "dom2"} } */