| 1 | /* Test program to trigger mcount overflow in profiling collection. |
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| 2 | Copyright (C) 2017-2023 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | /* Program with sufficiently complex, yet pointless, call graph |
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| 20 | that it will trigger an mcount overflow, when you set the |
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| 21 | minarcs/maxarcs tunables to very low values. */ |
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| 22 | |
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| 23 | #define PREVENT_TAIL_CALL asm volatile ("") |
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| 24 | |
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| 25 | /* Calls REP(n) macro 16 times, for n=0..15. |
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| 26 | * You need to define REP(n) before using this. |
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| 27 | */ |
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| 28 | #define REPS \ |
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| 29 | REP(0) REP(1) REP(2) REP(3) REP(4) REP(5) REP(6) REP(7) \ |
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| 30 | REP(8) REP(9) REP(10) REP(11) REP(12) REP(13) REP(14) REP(15) |
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| 31 | |
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| 32 | /* Defines 16 leaf functions named f1_0 to f1_15 */ |
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| 33 | #define REP(n) \ |
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| 34 | __attribute__ ((noinline, noclone, weak)) void f1_##n (void) {}; |
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| 35 | REPS |
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| 36 | #undef REP |
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| 37 | |
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| 38 | /* Calls all 16 leaf functions f1_* in succession */ |
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| 39 | __attribute__ ((noinline, noclone, weak)) void |
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| 40 | f2 (void) |
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| 41 | { |
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| 42 | # define REP(n) f1_##n(); |
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| 43 | REPS |
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| 44 | # undef REP |
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| 45 | PREVENT_TAIL_CALL; |
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| 46 | } |
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| 47 | |
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| 48 | /* Defines 16 functions named f2_0 to f2_15, which all just call f2 */ |
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| 49 | #define REP(n) \ |
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| 50 | __attribute__ ((noinline, noclone, weak)) void \ |
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| 51 | f2_##n (void) { f2(); PREVENT_TAIL_CALL; }; |
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| 52 | REPS |
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| 53 | #undef REP |
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| 54 | |
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| 55 | __attribute__ ((noinline, noclone, weak)) void |
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| 56 | f3 (int count) |
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| 57 | { |
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| 58 | for (int i = 0; i < count; ++i) |
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| 59 | { |
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| 60 | /* Calls f1_0(), f2_0(), f1_1(), f2_1(), f3_0(), etc */ |
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| 61 | # define REP(n) f1_##n(); f2_##n(); |
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| 62 | REPS |
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| 63 | # undef REP |
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| 64 | } |
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| 65 | } |
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| 66 | |
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| 67 | int |
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| 68 | main (void) |
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| 69 | { |
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| 70 | f3 (count: 1000); |
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| 71 | return 0; |
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| 72 | } |
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| 73 | |
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