| 1 | /* Implementation of profiling support. ARM EABI version. |
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| 2 | Copyright (C) 2008-2022 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 | /* Don't call mcount when calling mcount... */ |
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| 20 | #undef PROF |
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| 21 | |
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| 22 | #include <sysdep.h> |
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| 23 | |
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| 24 | #undef mcount |
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| 25 | |
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| 26 | #ifdef __thumb2__ |
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| 27 | .thumb |
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| 28 | #endif |
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| 29 | .syntax unified |
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| 30 | |
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| 31 | |
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| 32 | /* Use an assembly stub with a special ABI. The calling lr has been |
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| 33 | pushed to the stack (which will be misaligned). We should preserve |
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| 34 | all registers except ip and pop a word off the stack. |
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| 35 | |
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| 36 | NOTE: This assumes mcount_internal does not clobber any non-core |
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| 37 | (coprocessor) registers. Currently this is true, but may require |
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| 38 | additional attention in the future. |
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| 39 | |
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| 40 | The calling sequence looks something like: |
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| 41 | func: |
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| 42 | push {lr} |
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| 43 | bl __gnu_mcount_nc |
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| 44 | <function body> |
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| 45 | */ |
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| 46 | |
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| 47 | ENTRY(__gnu_mcount_nc) |
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| 48 | push {r0, r1, r2, r3, lr} |
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| 49 | cfi_adjust_cfa_offset (20) |
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| 50 | cfi_rel_offset (r0, 0) |
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| 51 | cfi_rel_offset (r1, 4) |
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| 52 | cfi_rel_offset (r2, 8) |
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| 53 | cfi_rel_offset (r3, 12) |
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| 54 | cfi_rel_offset (lr, 16) |
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| 55 | bic r1, lr, #1 |
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| 56 | ldr r0, [sp, #20] |
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| 57 | bl __mcount_internal |
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| 58 | pop {r0, r1, r2, r3, ip, lr} |
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| 59 | cfi_adjust_cfa_offset (-24) |
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| 60 | cfi_restore (r0) |
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| 61 | cfi_restore (r1) |
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| 62 | cfi_restore (r2) |
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| 63 | cfi_restore (r3) |
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| 64 | cfi_register (lr, ip) |
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| 65 | bx ip |
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| 66 | END(__gnu_mcount_nc) |
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| 67 | |
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| 68 | |
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| 69 | #include <gcc-compat.h> |
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| 70 | #include <shlib-compat.h> |
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| 71 | |
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| 72 | /* The new __gnu_mcount_nc entry point was introduced in 4.4, so the |
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| 73 | static library needs the old one only to support older compilers. |
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| 74 | Even in a configuration that only cares about newer compilers, the |
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| 75 | shared library might need it only for strict ABI compatibility. */ |
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| 76 | |
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| 77 | #if GCC_COMPAT (4, 3) || SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_19) |
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| 78 | |
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| 79 | /* Provide old mcount for backwards compatibility. This requires |
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| 80 | code be compiled with APCS frame pointers. */ |
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| 81 | |
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| 82 | ENTRY(__mcount_arm_compat) |
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| 83 | push {r0, r1, r2, r3, fp, lr} |
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| 84 | cfi_adjust_cfa_offset (24) |
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| 85 | cfi_rel_offset (r0, 0) |
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| 86 | cfi_rel_offset (r1, 4) |
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| 87 | cfi_rel_offset (r2, 8) |
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| 88 | cfi_rel_offset (r3, 12) |
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| 89 | cfi_rel_offset (fp, 16) |
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| 90 | cfi_rel_offset (lr, 20) |
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| 91 | movs r0, fp |
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| 92 | ittt ne |
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| 93 | ldrne r0, [r0, #-4] |
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| 94 | movsne r1, lr |
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| 95 | blne __mcount_internal |
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| 96 | # if defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__) |
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| 97 | pop {r0, r1, r2, r3, fp, lr} |
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| 98 | cfi_adjust_cfa_offset (-24) |
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| 99 | cfi_restore (r0) |
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| 100 | cfi_restore (r1) |
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| 101 | cfi_restore (r2) |
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| 102 | cfi_restore (r3) |
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| 103 | cfi_restore (fp) |
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| 104 | cfi_restore (lr) |
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| 105 | bx lr |
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| 106 | # else |
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| 107 | pop {r0, r1, r2, r3, fp, pc} |
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| 108 | # endif |
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| 109 | END(__mcount_arm_compat) |
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| 110 | |
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| 111 | #endif |
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| 112 | |
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| 113 | #if GCC_COMPAT (4, 3) |
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| 114 | |
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| 115 | strong_alias (__mcount_arm_compat, _mcount) |
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| 116 | |
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| 117 | /* The canonical name for the function is `_mcount' in both C and asm, |
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| 118 | but some old asm code might assume it's `mcount'. */ |
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| 119 | weak_alias (_mcount, mcount) |
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| 120 | |
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| 121 | #elif SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_19) |
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| 122 | |
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| 123 | compat_symbol (libc, __mcount_arm_compat, _mcount, GLIBC_2_0) |
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| 124 | |
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| 125 | strong_alias (__mcount_arm_compat, __mcount_arm_compat_1) |
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| 126 | compat_symbol (libc, __mcount_arm_compat_1, mcount, GLIBC_2_0) |
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| 127 | |
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| 128 | #endif |
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| 129 | |
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