gcc/testsuite/gcc.dg/sibcall-2.c

   1 /* Simple check that sibling calls are performed from a
   2    void non-leaf-function taking no arguments 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 (void);
  15 extern void track (void);
  16
  17 int n = 0;
  18 int main ()
  19 {
  20   recurser_void ();
  21   exit (0);
  22 }
  23
  24 void
  25 recurser_void (void)
  26 {
  27   if (n == 0 || n == 7)
  28     track ();
  29
  30   if (n == 10)
  31     return;
  32   n++;
  33   recurser_void ();
  34 }
  35
  36 void *trackpoint;
  37
  38 void
  39 track ()
  40 {
  41   char stackpos[1];
  42
  43   if (n == 0)
  44     trackpoint = stackpos;
  45   else if (n != 7 || trackpoint != stackpos)
  46     abort ();
  47 }