mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-23 21:40:12 +00:00
581c785bf3
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
137 lines
4.0 KiB
ArmAsm
137 lines
4.0 KiB
ArmAsm
/* Thread-local storage handling in the ELF dynamic linker. i386 version.
|
|
Copyright (C) 2004-2022 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/>. */
|
|
|
|
#include <sysdep.h>
|
|
#include <tls.h>
|
|
#include "tlsdesc.h"
|
|
|
|
.text
|
|
|
|
/* This function is used to compute the TP offset for symbols in
|
|
Static TLS, i.e., whose TP offset is the same for all
|
|
threads.
|
|
|
|
The incoming %eax points to the TLS descriptor, such that
|
|
0(%eax) points to _dl_tlsdesc_return itself, and 4(%eax) holds
|
|
the TP offset of the symbol corresponding to the object
|
|
denoted by the argument. */
|
|
|
|
.hidden _dl_tlsdesc_return
|
|
.global _dl_tlsdesc_return
|
|
.type _dl_tlsdesc_return,@function
|
|
cfi_startproc
|
|
.align 16
|
|
_dl_tlsdesc_return:
|
|
_CET_ENDBR
|
|
movl 4(%eax), %eax
|
|
ret
|
|
cfi_endproc
|
|
.size _dl_tlsdesc_return, .-_dl_tlsdesc_return
|
|
|
|
/* This function is used for undefined weak TLS symbols, for
|
|
which the base address (i.e., disregarding any addend) should
|
|
resolve to NULL.
|
|
|
|
%eax points to the TLS descriptor, such that 0(%eax) points to
|
|
_dl_tlsdesc_undefweak itself, and 4(%eax) holds the addend.
|
|
We return the addend minus the TP, such that, when the caller
|
|
adds TP, it gets the addend back. If that's zero, as usual,
|
|
that's most likely a NULL pointer. */
|
|
|
|
.hidden _dl_tlsdesc_undefweak
|
|
.global _dl_tlsdesc_undefweak
|
|
.type _dl_tlsdesc_undefweak,@function
|
|
cfi_startproc
|
|
.align 16
|
|
_dl_tlsdesc_undefweak:
|
|
_CET_ENDBR
|
|
movl 4(%eax), %eax
|
|
subl %gs:0, %eax
|
|
ret
|
|
cfi_endproc
|
|
.size _dl_tlsdesc_undefweak, .-_dl_tlsdesc_undefweak
|
|
|
|
#ifdef SHARED
|
|
.hidden _dl_tlsdesc_dynamic
|
|
.global _dl_tlsdesc_dynamic
|
|
.type _dl_tlsdesc_dynamic,@function
|
|
|
|
/* This function is used for symbols that need dynamic TLS.
|
|
|
|
%eax points to the TLS descriptor, such that 0(%eax) points to
|
|
_dl_tlsdesc_dynamic itself, and 4(%eax) points to a struct
|
|
tlsdesc_dynamic_arg object. It must return in %eax the offset
|
|
between the thread pointer and the object denoted by the
|
|
argument, without clobbering any registers.
|
|
|
|
The assembly code that follows is a rendition of the following
|
|
C code, hand-optimized a little bit.
|
|
|
|
ptrdiff_t
|
|
__attribute__ ((__regparm__ (1)))
|
|
_dl_tlsdesc_dynamic (struct tlsdesc *tdp)
|
|
{
|
|
struct tlsdesc_dynamic_arg *td = tdp->arg;
|
|
dtv_t *dtv = *(dtv_t **)((char *)__thread_pointer + DTV_OFFSET);
|
|
if (__builtin_expect (td->gen_count <= dtv[0].counter
|
|
&& (dtv[td->tlsinfo.ti_module].pointer.val
|
|
!= TLS_DTV_UNALLOCATED),
|
|
1))
|
|
return dtv[td->tlsinfo.ti_module].pointer.val + td->tlsinfo.ti_offset
|
|
- __thread_pointer;
|
|
|
|
return ___tls_get_addr (&td->tlsinfo) - __thread_pointer;
|
|
}
|
|
*/
|
|
cfi_startproc
|
|
.align 16
|
|
_dl_tlsdesc_dynamic:
|
|
_CET_ENDBR
|
|
/* Like all TLS resolvers, preserve call-clobbered registers.
|
|
We need two scratch regs anyway. */
|
|
subl $28, %esp
|
|
cfi_adjust_cfa_offset (28)
|
|
movl %ecx, 20(%esp)
|
|
movl %edx, 24(%esp)
|
|
movl TLSDESC_ARG(%eax), %eax
|
|
movl %gs:DTV_OFFSET, %edx
|
|
movl TLSDESC_GEN_COUNT(%eax), %ecx
|
|
cmpl (%edx), %ecx
|
|
ja .Lslow
|
|
movl TLSDESC_MODID(%eax), %ecx
|
|
movl (%edx,%ecx,8), %edx
|
|
cmpl $-1, %edx
|
|
je .Lslow
|
|
movl TLSDESC_MODOFF(%eax), %eax
|
|
addl %edx, %eax
|
|
.Lret:
|
|
movl 20(%esp), %ecx
|
|
subl %gs:0, %eax
|
|
movl 24(%esp), %edx
|
|
addl $28, %esp
|
|
cfi_adjust_cfa_offset (-28)
|
|
ret
|
|
.p2align 4,,7
|
|
.Lslow:
|
|
cfi_adjust_cfa_offset (28)
|
|
call HIDDEN_JUMPTARGET (___tls_get_addr)
|
|
jmp .Lret
|
|
cfi_endproc
|
|
.size _dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic
|
|
#endif /* SHARED */
|