1  /* Simple check that sibling calls are performed from a
       2     void non-leaf-function taking one int argument calling a function which
       3     is about the same as itself.
       4  
       5     Copyright (C) 2002 Free Software Foundation Inc.
       6     Contributed by Hans-Peter Nilsson  <hp@bitrange.com>  */
       7  
       8  /* { dg-do run { xfail { { cris-*-* h8300-*-* hppa*64*-*-* m32r-*-* mcore-*-* mn10300-*-* msp430*-*-* nds32*-*-* xstormy16-*-* v850*-*-* vax-*-* xtensa*-*-* nvptx*-*-* } || { arm*-*-* && { ! arm32 } } } } } */
       9  /* -mlongcall disables sibcall patterns.  */
      10  /* { dg-skip-if "" { powerpc*-*-* } { "-mlongcall" } { "" } } */
      11  /* { dg-options "-O2 -foptimize-sibling-calls" } */
      12  
      13  /* The option -foptimize-sibling-calls is the default, but serves as
      14     marker.  This test is xfailed on targets without sibcall patterns
      15     (except targets where the test does not work due to the return address
      16     not saved on the regular stack).  */
      17  
      18  extern void abort (void);
      19  extern void exit (int);
      20  
      21  /* Sibcalls are not supported in MIPS16 mode, which has direct calls but
      22     not direct jumps.  */
      23  #ifdef __mips
      24  #define ATTR __attribute__((nomips16))
      25  #else
      26  #define ATTR
      27  #endif
      28  
      29  static ATTR void recurser_void1 (int);
      30  static ATTR void recurser_void2 (int);
      31  extern void track (int);
      32  
      33  int main ()
      34  {
      35    recurser_void1 (0);
      36    exit (0);
      37  }
      38  
      39  /* The functions should get the same stack-frame, and best way to make it
      40     reasonably sure is to make them have the same contents (regarding the
      41     n tests).  */
      42  
      43  static void __attribute__((noipa)) ATTR
      44  recurser_void1 (int n)
      45  {
      46    if (n == 0 || n == 7 || n == 8)
      47      track (n);
      48  
      49    if (n == 10)
      50      return;
      51  
      52    recurser_void2 (n + 1);
      53  }
      54  
      55  static void __attribute__((noipa)) ATTR
      56  recurser_void2 (int n)
      57  {
      58    if (n == 0 || n == 7 || n == 8)
      59      track (n);
      60  
      61    if (n == 10)
      62      return;
      63  
      64    recurser_void1 (n + 1);
      65  }
      66  
      67  void *trackpoint;
      68  
      69  void __attribute__ ((noipa))
      70  track (int n)
      71  {
      72    char stackpos[1];
      73  
      74    if (n == 0)
      75      trackpoint = stackpos;
      76    else if ((n != 7 && n != 8) || trackpoint != stackpos)
      77      abort ();
      78  }