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/* Implementation of profiling support. ARM EABI version.
Copyright (C) 2008-2021 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/>. */
/* Don't call mcount when calling mcount... */
#undef PROF
#include <sysdep.h>
#undef mcount
#ifdef __thumb2__
.thumb
#endif
.syntax unified
/* Use an assembly stub with a special ABI. The calling lr has been
pushed to the stack (which will be misaligned). We should preserve
all registers except ip and pop a word off the stack.
NOTE: This assumes mcount_internal does not clobber any non-core
(coprocessor) registers. Currently this is true, but may require
additional attention in the future.
The calling sequence looks something like:
func:
push {lr}
bl __gnu_mcount_nc
<function body>
*/
ENTRY(__gnu_mcount_nc)
push {r0, r1, r2, r3, lr}
cfi_adjust_cfa_offset (20)
cfi_rel_offset (r0, 0)
cfi_rel_offset (r1, 4)
cfi_rel_offset (r2, 8)
cfi_rel_offset (r3, 12)
cfi_rel_offset (lr, 16)
bic r1, lr, #1
ldr r0, [sp, #20]
bl __mcount_internal
pop {r0, r1, r2, r3, ip, lr}
cfi_adjust_cfa_offset (-24)
cfi_restore (r0)
cfi_restore (r1)
cfi_restore (r2)
cfi_restore (r3)
cfi_register (lr, ip)
bx ip
END(__gnu_mcount_nc)
#include <gcc-compat.h>
#include <shlib-compat.h>
/* The new __gnu_mcount_nc entry point was introduced in 4.4, so the
static library needs the old one only to support older compilers.
Even in a configuration that only cares about newer compilers, the
shared library might need it only for strict ABI compatibility. */
#if GCC_COMPAT (4, 3) || SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_19)
/* Provide old mcount for backwards compatibility. This requires
code be compiled with APCS frame pointers. */
ENTRY(__mcount_arm_compat)
push {r0, r1, r2, r3, fp, lr}
cfi_adjust_cfa_offset (24)
cfi_rel_offset (r0, 0)
cfi_rel_offset (r1, 4)
cfi_rel_offset (r2, 8)
cfi_rel_offset (r3, 12)
cfi_rel_offset (fp, 16)
cfi_rel_offset (lr, 20)
movs r0, fp
ittt ne
ldrne r0, [r0, #-4]
movsne r1, lr
blne __mcount_internal
# if defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__)
pop {r0, r1, r2, r3, fp, lr}
cfi_adjust_cfa_offset (-24)
cfi_restore (r0)
cfi_restore (r1)
cfi_restore (r2)
cfi_restore (r3)
cfi_restore (fp)
cfi_restore (lr)
bx lr
# else
pop {r0, r1, r2, r3, fp, pc}
# endif
END(__mcount_arm_compat)
#endif
#if GCC_COMPAT (4, 3)
strong_alias (__mcount_arm_compat, _mcount)
/* The canonical name for the function is `_mcount' in both C and asm,
but some old asm code might assume it's `mcount'. */
weak_alias (_mcount, mcount)
#elif SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_19)
compat_symbol (libc, __mcount_arm_compat, _mcount, GLIBC_2_0)
strong_alias (__mcount_arm_compat, __mcount_arm_compat_1)
compat_symbol (libc, __mcount_arm_compat_1, mcount, GLIBC_2_0)
#endif
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