mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-15 01:21:06 +00:00
105 lines
3.7 KiB
C
105 lines
3.7 KiB
C
/* Thread-local storage handling in the ELF dynamic linker. s390 version.
|
|
Copyright (C) 2003-2020 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/>. */
|
|
|
|
|
|
/* Type used for the representation of TLS information in the GOT. */
|
|
typedef struct
|
|
{
|
|
unsigned long int ti_module;
|
|
unsigned long int ti_offset;
|
|
} tls_index;
|
|
|
|
|
|
#ifdef SHARED
|
|
|
|
extern unsigned long __tls_get_offset (unsigned long got_offset);
|
|
|
|
# if IS_IN (rtld)
|
|
|
|
# include <shlib-compat.h>
|
|
|
|
/* dl-tls.c declares __tls_get_addr as an exported symbol if it is not defined
|
|
as a macro. It seems suitable to do that in the generic code because all
|
|
architectures other than s390 export __tls_get_addr. The declaration causes
|
|
problems in s390 though, so we define __tls_get_addr here to avoid declaring
|
|
__tls_get_addr again. */
|
|
# define __tls_get_addr __tls_get_addr
|
|
|
|
extern void *__tls_get_addr (tls_index *ti) attribute_hidden;
|
|
/* Make a temporary alias of __tls_get_addr to remove the hidden
|
|
attribute. Then export __tls_get_addr as __tls_get_addr_internal
|
|
for use from libc. We do not want to export __tls_get_addr, but we
|
|
do need to use it from libc when looking up the address of a TLS
|
|
variable. We don't use __tls_get_offset because it requires r12 to
|
|
be setup and that might not always be true. Either way it's more
|
|
optimal to use __tls_get_addr directly (that's what
|
|
__tls_get_offset does anyways). */
|
|
strong_alias (__tls_get_addr, __tls_get_addr_internal_tmp);
|
|
versioned_symbol (ld, __tls_get_addr_internal_tmp,
|
|
__tls_get_addr_internal, GLIBC_PRIVATE);
|
|
|
|
/* The special thing about the s390 TLS ABI is that we do not have the
|
|
standard __tls_get_addr function but the __tls_get_offset function
|
|
which differs in two important aspects:
|
|
1) __tls_get_offset gets a got offset instead of a pointer to the
|
|
tls_index structure
|
|
2) __tls_get_offset returns the offset of the requested variable to
|
|
the thread descriptor instead of a pointer to the variable.
|
|
*/
|
|
# ifdef __s390x__
|
|
__asm__("\n\
|
|
.text\n\
|
|
.globl __tls_get_offset\n\
|
|
.type __tls_get_offset, @function\n\
|
|
.align 4\n\
|
|
__tls_get_offset:\n\
|
|
la %r2,0(%r2,%r12)\n\
|
|
jg __tls_get_addr\n\
|
|
");
|
|
# elif defined __s390__
|
|
__asm__("\n\
|
|
.text\n\
|
|
.globl __tls_get_offset\n\
|
|
.type __tls_get_offset, @function\n\
|
|
.align 4\n\
|
|
__tls_get_offset:\n\
|
|
basr %r3,0\n\
|
|
0: la %r2,0(%r2,%r12)\n\
|
|
l %r4,1f-0b(%r3)\n\
|
|
b 0(%r4,%r3)\n\
|
|
1: .long __tls_get_addr - 0b\n\
|
|
");
|
|
# endif
|
|
# else /* IS_IN (rtld) */
|
|
extern void *__tls_get_addr_internal (tls_index *ti);
|
|
# endif /* !IS_IN (rtld) */
|
|
|
|
# define GET_ADDR_OFFSET \
|
|
(ti->ti_offset - (unsigned long) __builtin_thread_pointer ())
|
|
|
|
/* Use the privately exported __tls_get_addr_internal instead of
|
|
__tls_get_offset in order to avoid the __tls_get_offset special
|
|
linkage requiring the GOT pointer to be set up in r12. The
|
|
compiler will take care of setting up r12 only if itself issued the
|
|
__tls_get_offset call. */
|
|
# define __TLS_GET_ADDR(__ti) \
|
|
({ __tls_get_addr_internal (__ti) \
|
|
+ (unsigned long) __builtin_thread_pointer (); })
|
|
|
|
#endif
|