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/* Test program to trigger mcount overflow in profiling collection.
Copyright (C) 2017-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* Program with sufficiently complex, yet pointless, call graph
that it will trigger an mcount overflow, when you set the
minarcs/maxarcs tunables to very low values. */
#define PREVENT_TAIL_CALL asm volatile ("")
/* Calls REP(n) macro 16 times, for n=0..15.
* You need to define REP(n) before using this.
*/
#define REPS \
REP(0) REP(1) REP(2) REP(3) REP(4) REP(5) REP(6) REP(7) \
REP(8) REP(9) REP(10) REP(11) REP(12) REP(13) REP(14) REP(15)
/* Defines 16 leaf functions named f1_0 to f1_15 */
#define REP(n) \
__attribute__ ((noinline, noclone, weak)) void f1_##n (void) {};
REPS
#undef REP
/* Calls all 16 leaf functions f1_* in succession */
__attribute__ ((noinline, noclone, weak)) void
f2 (void)
{
# define REP(n) f1_##n();
REPS
# undef REP
PREVENT_TAIL_CALL;
}
/* Defines 16 functions named f2_0 to f2_15, which all just call f2 */
#define REP(n) \
__attribute__ ((noinline, noclone, weak)) void \
f2_##n (void) { f2(); PREVENT_TAIL_CALL; };
REPS
#undef REP
__attribute__ ((noinline, noclone, weak)) void
f3 (int count)
{
for (int i = 0; i < count; ++i)
{
/* Calls f1_0(), f2_0(), f1_1(), f2_1(), f3_0(), etc */
# define REP(n) f1_##n(); f2_##n();
REPS
# undef REP
}
}
int
main (void)
{
f3 (1000);
return 0;
}
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