gcc/testsuite/gcc.dg/sibcall-1.c

   1 /* Simple check that sibling calls are performed from a
   2    void non-leaf-function taking one int argument calling itself.
   3
   4    Copyright (C) 2002 Free Software Foundation Inc.
   5    Contributed by Hans-Peter Nilsson  <hp@bitrange.com>  */
   6
   7 /* { dg-do run } */
   8 /* { dg-options "-O2 -foptimize-sibling-calls" } */
   9
  10 /* The option -foptimize-sibling-calls is the default, but serves as
  11    marker.  Self-recursion tail calls are optimized for all targets,
  12    regardless of presence of sibcall patterns.  */
  13
  14 extern void recurser_void (int);
  15 extern void track (int);
  16
  17 int main ()
  18 {
  19   recurser_void (0);
  20   exit (0);
  21 }
  22
  23 void
  24 recurser_void (int n)
  25 {
  26   if (n == 0 || n == 7)
  27     track (n);
  28
  29   if (n == 10)
  30     return;
  31
  32   recurser_void (n + 1);
  33 }
  34
  35 void *trackpoint;
  36
  37 void
  38 track (int n)
  39 {
  40   char stackpos[1];
  41
  42   if (n == 0)
  43     trackpoint = stackpos;
  44   else if (n != 7 || trackpoint != stackpos)
  45     abort ();
  46 }