gcc/testsuite/gcc.dg/sibcall-10.c

   1 /* Simple check that sibling calls are performed from a
   2    void non-leaf-function taking no arguments 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-*-* crisv32-*-* h8300-*-* hppa*64*-*-* m32r-*-* mcore-*-* mn10300-*-* msp430*-*-* nds32*-*-* xstormy16-*-* v850*-*-* vax-*-* xtensa*-*-* } || { arm*-*-* && { ! arm32 } } } } } */
   9 /* -mlongcall disables sibcall patterns.  */
  10 /* { dg-skip-if "" { powerpc*-*-* } { "-mlongcall" } { "" } } */
  11 /* -msave-restore disables sibcall patterns.  */
  12 /* { dg-skip-if "" { riscv*-*-* } { "-msave-restore" } { "" } } */
  13 /* { dg-options "-O2 -foptimize-sibling-calls" } */
  14
  15 /* The option -foptimize-sibling-calls is the default, but serves as
  16    marker.  This test is xfailed on targets without sibcall patterns
  17    (except targets where the test does not work due to the return address
  18    not saved on the regular stack).  */
  19
  20 extern void abort (void);
  21 extern void exit (int);
  22
  23 /* Sibcalls are not supported in MIPS16 mode, which has direct calls but
  24    not direct jumps.  */
  25 #ifdef __mips
  26 #define ATTR __attribute__((nomips16))
  27 #else
  28 #define ATTR
  29 #endif
  30
  31 static ATTR void recurser_void1 (void);
  32 static ATTR void recurser_void2 (void);
  33 extern void track (void);
  34 volatile int v;
  35
  36 int n = 0;
  37 int main ()
  38 {
  39   recurser_void1 ();
  40   if (v != 5)
  41     abort ();
  42   exit (0);
  43 }
  44
  45 /* The functions should get the same stack-frame, and best way to make it
  46    reasonably sure is to make them have the same contents (regarding the
  47    n tests).  */
  48
  49 static void __attribute__((noinline)) ATTR
  50 recurser_void1 (void)
  51 {
  52   if (n == 0 || n == 7 || n == 8)
  53     track ();
  54
  55   if (n == 10)
  56     return;
  57   n++;
  58   recurser_void2 ();
  59 }
  60
  61 static void __attribute__((noinline)) ATTR
  62 recurser_void2 (void)
  63 {
  64   if (n == 0 || n == 7 || n == 8)
  65     track ();
  66
  67   if (n == 10)
  68     return;
  69   n++;
  70   v++;
  71   recurser_void1 ();
  72 }
  73
  74 void *trackpoint;
  75
  76 void __attribute__ ((noinline))
  77 track ()
  78 {
  79   char stackpos[1];
  80
  81   if (n == 0)
  82     trackpoint = stackpos;
  83   else if ((n != 7 && n != 8) || trackpoint != stackpos)
  84     abort ();
  85 }