1/* Thread-local storage handling in the ELF dynamic linker. x86-64 version.
2 Copyright (C) 2017-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifdef SHARED
20/* Work around GCC PR58066, due to which __tls_get_addr may be called
21 with an unaligned stack. The compat implementation is in
22 tls_get_addr-compat.S. */
23
24# include <dl-tls.h>
25
26/* Define __tls_get_addr within elf/dl-tls.c under a different
27 name. */
28extern __typeof__ (__tls_get_addr) ___tls_get_addr;
29
30# define __tls_get_addr ___tls_get_addr
31# include <elf/dl-tls.c>
32# undef __tls_get_addr
33
34hidden_ver (___tls_get_addr, __tls_get_addr)
35
36/* Only handle slow paths for __tls_get_addr. */
37attribute_hidden
38void *
39__tls_get_addr_slow (GET_ADDR_ARGS)
40{
41 dtv_t *dtv = THREAD_DTV ();
42
43 size_t gen = atomic_load_relaxed (&GL(dl_tls_generation));
44 if (__glibc_unlikely (dtv[0].counter != gen))
45 return update_get_addr (GET_ADDR_PARAM);
46
47 return tls_get_addr_tail (GET_ADDR_PARAM, dtv, NULL);
48}
49#else
50
51/* No compatibility symbol needed. */
52# include <elf/dl-tls.c>
53
54#endif
55