glibc/sysdeps/x86_64/dl-tlsdesc.S
H.J. Lu befe2d3c4d x86-64: Don't use SSE resolvers for ISA level 3 or above
When glibc is built with ISA level 3 or above enabled, SSE resolvers
aren't available and glibc fails to build:

ld: .../elf/librtld.os: in function `init_cpu_features':
.../elf/../sysdeps/x86/cpu-features.c:1200:(.text+0x1445f): undefined reference to `_dl_runtime_resolve_fxsave'
ld: .../elf/librtld.os: relocation R_X86_64_PC32 against undefined hidden symbol `_dl_runtime_resolve_fxsave' can not be used when making a shared object
/usr/local/bin/ld: final link failed: bad value

For ISA level 3 or above, don't use _dl_runtime_resolve_fxsave nor
_dl_tlsdesc_dynamic_fxsave.

This fixes BZ #31429.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
2024-02-28 11:49:30 -08:00

106 lines
3.3 KiB
ArmAsm

/* Thread-local storage handling in the ELF dynamic linker. x86_64 version.
Copyright (C) 2004-2024 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 <cpu-features-offsets.h>
#include <features-offsets.h>
#include <isa-level.h>
#include "tlsdesc.h"
#include "dl-trampoline-save.h"
/* Area on stack to save and restore registers used for parameter
passing when calling _dl_tlsdesc_dynamic. */
#define REGISTER_SAVE_RCX 0
#define REGISTER_SAVE_RDX (REGISTER_SAVE_RCX + 8)
#define REGISTER_SAVE_R8 (REGISTER_SAVE_RDX + 8)
#define REGISTER_SAVE_R9 (REGISTER_SAVE_R8 + 8)
#define REGISTER_SAVE_R10 (REGISTER_SAVE_R9 + 8)
#define REGISTER_SAVE_R11 (REGISTER_SAVE_R10 + 8)
.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 %rax points to the TLS descriptor, such that
0(%rax) points to _dl_tlsdesc_return itself, and 8(%rax) 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
movq 8(%rax), %rax
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.
%rax points to the TLS descriptor, such that 0(%rax) points to
_dl_tlsdesc_undefweak itself, and 8(%rax) 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
movq 8(%rax), %rax
sub %fs:0, %RAX_LP
ret
cfi_endproc
.size _dl_tlsdesc_undefweak, .-_dl_tlsdesc_undefweak
#ifdef SHARED
# if MINIMUM_X86_ISA_LEVEL < AVX_X86_ISA_LEVEL
# define USE_FXSAVE
# define STATE_SAVE_ALIGNMENT 16
# define _dl_tlsdesc_dynamic _dl_tlsdesc_dynamic_fxsave
# include "dl-tlsdesc-dynamic.h"
# undef _dl_tlsdesc_dynamic
# undef USE_FXSAVE
# endif
# define USE_XSAVE
# define STATE_SAVE_ALIGNMENT 64
# define _dl_tlsdesc_dynamic _dl_tlsdesc_dynamic_xsave
# include "dl-tlsdesc-dynamic.h"
# undef _dl_tlsdesc_dynamic
# undef USE_XSAVE
# define USE_XSAVEC
# define STATE_SAVE_ALIGNMENT 64
# define _dl_tlsdesc_dynamic _dl_tlsdesc_dynamic_xsavec
# include "dl-tlsdesc-dynamic.h"
# undef _dl_tlsdesc_dynamic
# undef USE_XSAVEC
#endif /* SHARED */