[PATCH v5] i386: Update ___tls_get_addr to preserve vector registers
Adhemerval Zanella Netto
adhemerval.zanella@linaro.org
Wed Jun 18 19:41:10 GMT 2025
On 17/06/25 23:06, H.J. Lu wrote:
> Compiler generates the following instruction sequence for dynamic TLS
> access:
>
> leal tls_var@tlsgd(,%ebx,1), %eax
> call ___tls_get_addr@PLT
>
> CALL instruction is transparent to compiler which assumes all registers,
> except for EFLAGS, AX, CX, and DX, are unchanged after CALL. But
> ___tls_get_addr is a normal function which doesn't preserve any vector
> registers.
>
> 1. Rename the generic __tls_get_addr function to ___tls_get_addr_internal.
> 2. Change ___tls_get_addr to a wrapper function with implementations for
> FNSAVE, FXSAVE, XSAVE and XSAVEC to save and restore all vector registers.
> 3. dl-tlsdesc-dynamic.h has:
>
> _dl_tlsdesc_dynamic:
> /* Like all TLS resolvers, preserve call-clobbered registers.
> We need two scratch regs anyway. */
> subl $32, %esp
> cfi_adjust_cfa_offset (32)
>
> It is wrong to use
>
> movl %ebx, -28(%esp)
> movl %esp, %ebx
> cfi_def_cfa_register(%ebx)
> ...
> mov %ebx, %esp
> cfi_def_cfa_register(%esp)
> movl -28(%esp), %ebx
>
> to preserve EBX on stack. Fix it with:
>
> movl %ebx, 28(%esp)
> movl %esp, %ebx
> cfi_def_cfa_register(%ebx)
> ...
> mov %ebx, %esp
> cfi_def_cfa_register(%esp)
> movl 28(%esp), %ebx
>
> 4. Update _dl_tlsdesc_dynamic to call ___tls_get_addr_internal directly.
> 5. Add have-test-mtls-traditional to compile tst-tls23-mod.c with
> traditional TLS variant to verify the fix.
> 6. Define DL_RUNTIME_RESOLVE_REALIGN_STACK in sysdeps/x86/sysdep.h.
>
> This fixes BZ #32996.
>
> Co-Authored-By: Adhemerval Zanella <adhemerval.zanella@linaro.org>
> Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
>
>
LGTM, thanks. I see no issues on aarch64, armhf, or powerpc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
> From 92ae5c3874aa98a5118b64051b7a48c444df46fd Mon Sep 17 00:00:00 2001
> From: "H.J. Lu" <hjl.tools@gmail.com>
> Date: Mon, 9 Jun 2025 05:22:10 +0800
> Subject: [PATCH v5] i386: Update ___tls_get_addr to preserve vector registers
>
> Compiler generates the following instruction sequence for dynamic TLS
> access:
>
> leal tls_var@tlsgd(,%ebx,1), %eax
> call ___tls_get_addr@PLT
>
> CALL instruction is transparent to compiler which assumes all registers,
> except for EFLAGS, AX, CX, and DX, are unchanged after CALL. But
> ___tls_get_addr is a normal function which doesn't preserve any vector
> registers.
>
> 1. Rename the generic __tls_get_addr function to ___tls_get_addr_internal.
> 2. Change ___tls_get_addr to a wrapper function with implementations for
> FNSAVE, FXSAVE, XSAVE and XSAVEC to save and restore all vector registers.
> 3. dl-tlsdesc-dynamic.h has:
>
> _dl_tlsdesc_dynamic:
> /* Like all TLS resolvers, preserve call-clobbered registers.
> We need two scratch regs anyway. */
> subl $32, %esp
> cfi_adjust_cfa_offset (32)
>
> It is wrong to use
>
> movl %ebx, -28(%esp)
> movl %esp, %ebx
> cfi_def_cfa_register(%ebx)
> ...
> mov %ebx, %esp
> cfi_def_cfa_register(%esp)
> movl -28(%esp), %ebx
>
> to preserve EBX on stack. Fix it with:
>
> movl %ebx, 28(%esp)
> movl %esp, %ebx
> cfi_def_cfa_register(%ebx)
> ...
> mov %ebx, %esp
> cfi_def_cfa_register(%esp)
> movl 28(%esp), %ebx
>
> 4. Update _dl_tlsdesc_dynamic to call ___tls_get_addr_internal directly.
> 5. Add have-test-mtls-traditional to compile tst-tls23-mod.c with
> traditional TLS variant to verify the fix.
> 6. Define DL_RUNTIME_RESOLVE_REALIGN_STACK in sysdeps/x86/sysdep.h.
>
> This fixes BZ #32996.
>
> Co-Authored-By: Adhemerval Zanella <adhemerval.zanella@linaro.org>
> Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
> ---
> configure | 38 ++++++
> configure.ac | 13 ++
> elf/Makefile | 9 ++
> elf/tst-tls23-mod.c | 32 +++++
> elf/tst-tls23.c | 106 +++++++++++++++
> .../dl-trampoline-save.h => elf/tst-tls23.h | 34 +++--
> sysdeps/aarch64/preconfigure | 1 +
> sysdeps/i386/Makefile | 4 +-
> sysdeps/i386/dl-tls-get-addr.c | 68 ++++++++++
> sysdeps/i386/dl-tls.h | 28 +---
> sysdeps/i386/dl-tlsdesc-dynamic.h | 108 +--------------
> sysdeps/i386/dl-tlsdesc.S | 17 ---
> sysdeps/i386/tls-get-addr-wrapper.h | 127 ++++++++++++++++++
> sysdeps/i386/tls_get_addr.S | 57 ++++++++
> sysdeps/i386/tls_get_addr.h | 42 ++++++
> sysdeps/loongarch/preconfigure | 1 +
> sysdeps/loongarch/preconfigure.ac | 1 +
> sysdeps/powerpc/Makefile | 5 +
> sysdeps/x86/Makefile | 16 ++-
> sysdeps/x86/sysdep.h | 23 ++++
> sysdeps/x86/tst-tls23.c | 22 +++
> sysdeps/x86/tst-tls23.h | 35 +++++
> sysdeps/x86_64/Makefile | 3 -
> sysdeps/x86_64/dl-tlsdesc.S | 1 -
> sysdeps/x86_64/dl-trampoline.S | 1 -
> 25 files changed, 623 insertions(+), 169 deletions(-)
> create mode 100644 elf/tst-tls23-mod.c
> create mode 100644 elf/tst-tls23.c
> rename sysdeps/x86_64/dl-trampoline-save.h => elf/tst-tls23.h (52%)
> create mode 100644 sysdeps/i386/dl-tls-get-addr.c
> create mode 100644 sysdeps/i386/tls-get-addr-wrapper.h
> create mode 100644 sysdeps/i386/tls_get_addr.S
> create mode 100644 sysdeps/i386/tls_get_addr.h
> create mode 100644 sysdeps/x86/tst-tls23.c
> create mode 100644 sysdeps/x86/tst-tls23.h
>
> diff --git a/configure b/configure
> index efc9203dda..53f7d1fce8 100755
> --- a/configure
> +++ b/configure
> @@ -4931,6 +4931,9 @@ with_fp_cond=1
> # A preconfigure script may define another name to TLS descriptor variant
> mtls_descriptor=gnu2
>
> +# A preconfigure script may define another name to traditional TLS variant
> +mtls_traditional=gnu
> +
> if frags=`ls -d $srcdir/sysdeps/*/preconfigure 2> /dev/null`
> then
> { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for sysdeps preconfigure fragments" >&5
> @@ -7490,6 +7493,41 @@ rm -f conftest*
> config_vars="$config_vars
> have-test-mtls-descriptor = $libc_cv_test_mtls_descriptor"
>
> +
> +cat > conftest.c <<EOF
> +$conftest_code
> +EOF
> +
> +saved_CC="$CC"
> +CC="$TEST_CC"
> +{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for traditional tls support in testing" >&5
> +printf %s "checking for traditional tls support in testing... " >&6; }
> +if test ${libc_cv_test_mtls_traditional+y}
> +then :
> + printf %s "(cached) " >&6
> +else case e in #(
> + e) if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS -fPIC -mtls-dialect=$mtls_traditional -nostdlib -nostartfiles -shared conftest.c -o conftest 1>&5'
> + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
> + (eval $ac_try) 2>&5
> + ac_status=$?
> + printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
> + test $ac_status = 0; }; }
> + then
> + libc_cv_test_mtls_traditional=$mtls_traditional
> + else
> + libc_cv_test_mtls_traditional=no
> + fi ;;
> +esac
> +fi
> +{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_cv_test_mtls_traditional" >&5
> +printf "%s\n" "$libc_cv_test_mtls_traditional" >&6; }
> +
> +CC="$saved_CC"
> +
> +rm -f conftest*
> +config_vars="$config_vars
> +have-test-mtls-traditional = $libc_cv_test_mtls_traditional"
> +
> conftest_code="
> void __foo (void)
> {
> diff --git a/configure.ac b/configure.ac
> index 6d00b473e8..09d2ab721c 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -483,6 +483,9 @@ with_fp_cond=1
> # A preconfigure script may define another name to TLS descriptor variant
> mtls_descriptor=gnu2
>
> +# A preconfigure script may define another name to traditional TLS variant
> +mtls_traditional=gnu
> +
> dnl Let sysdeps/*/preconfigure act here.
> LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
>
> @@ -1401,6 +1404,16 @@ LIBC_TRY_TEST_CC_COMMAND([for tls descriptor support],
> LIBC_CONFIG_VAR([have-test-mtls-descriptor],
> [$libc_cv_test_mtls_descriptor])
>
> +dnl Check if TEST_CC support traditional tls.
> +LIBC_TRY_TEST_CC_COMMAND([for traditional tls support],
> + [$conftest_code],
> + [-fPIC -mtls-dialect=$mtls_traditional -nostdlib -nostartfiles -shared],
> + libc_cv_test_mtls_traditional,
> + [libc_cv_test_mtls_traditional=$mtls_traditional],
> + [libc_cv_test_mtls_traditional=no])
> +LIBC_CONFIG_VAR([have-test-mtls-traditional],
> + [$libc_cv_test_mtls_traditional])
> +
> dnl clang emits an warning for a double alias redirection, to warn the
> dnl original symbol is sed even when weak definition overrides it.
> dnl It is a usual pattern for weak_alias, where multiple alias point to
> diff --git a/elf/Makefile b/elf/Makefile
> index 362523ff11..05a78dc9a5 100644
> --- a/elf/Makefile
> +++ b/elf/Makefile
> @@ -496,6 +496,7 @@ tests += \
> tst-tls21 \
> tst-tls22 \
> tst-tls22-gnu2 \
> + tst-tls23 \
> tst-tlsalign \
> tst-tlsalign-extern \
> tst-tlsgap \
> @@ -1023,6 +1024,7 @@ modules-names += \
> tst-tls22-mod1-gnu2 \
> tst-tls22-mod2 \
> tst-tls22-mod2-gnu2 \
> + tst-tls23-mod \
> tst-tlsalign-lib \
> tst-tlsgap-mod0 \
> tst-tlsgap-mod1 \
> @@ -3410,6 +3412,13 @@ tst-tls22-mod1-gnu2.so-no-z-defs = yes
> tst-tls22-mod2.so-no-z-defs = yes
> tst-tls22-mod2-gnu2.so-no-z-defs = yes
>
> +$(objpfx)tst-tls23: $(shared-thread-library)
> +$(objpfx)tst-tls23.out: $(objpfx)tst-tls23-mod.so
> +
> +ifneq (no,$(have-test-mtls-traditional))
> +CFLAGS-tst-tls23-mod.c += -mtls-dialect=$(have-test-mtls-traditional)
> +endif
> +
> ifeq ($(have-test-cc-cflags-fsemantic-interposition),yes)
> # Compiler may default to -fno-semantic-interposition. These modules
> # must be compiled with -fsemantic-interposition.
> diff --git a/elf/tst-tls23-mod.c b/elf/tst-tls23-mod.c
> new file mode 100644
> index 0000000000..3ee4c70e40
> --- /dev/null
> +++ b/elf/tst-tls23-mod.c
> @@ -0,0 +1,32 @@
> +/* DSO used by tst-tls23.
> + Copyright (C) 2025 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 <tst-tls23.h>
> +
> +__thread struct tls tls_var0 __attribute__ ((visibility ("hidden")));
> +
> +struct tls *
> +apply_tls (struct tls *p)
> +{
> + INIT_TLS_CALL ();
> + BEFORE_TLS_CALL ();
> + tls_var0 = *p;
> + struct tls *ret = &tls_var0;
> + AFTER_TLS_CALL ();
> + return ret;
> +}
> diff --git a/elf/tst-tls23.c b/elf/tst-tls23.c
> new file mode 100644
> index 0000000000..afe594c067
> --- /dev/null
> +++ b/elf/tst-tls23.c
> @@ -0,0 +1,106 @@
> +/* Test that __tls_get_addr preserves caller-saved registers.
> + Copyright (C) 2025 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
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <dlfcn.h>
> +#include <pthread.h>
> +#include <support/xdlfcn.h>
> +#include <support/xthread.h>
> +#include <support/check.h>
> +#include <support/test-driver.h>
> +#include <tst-tls23.h>
> +
> +#ifndef IS_SUPPORTED
> +# define IS_SUPPORTED() true
> +#endif
> +
> +/* An architecture can define it to clobber caller-saved registers in
> + malloc below to verify that __tls_get_addr won't change caller-saved
> + registers. */
> +#ifndef PREPARE_MALLOC
> +# define PREPARE_MALLOC()
> +#endif
> +
> +extern void * __libc_malloc (size_t);
> +
> +size_t malloc_counter = 0;
> +
> +void *
> +malloc (size_t n)
> +{
> + PREPARE_MALLOC ();
> + malloc_counter++;
> + return __libc_malloc (n);
> +}
> +
> +static void *mod;
> +static const char *modname = "tst-tls23-mod.so";
> +
> +static void
> +open_mod (void)
> +{
> + mod = xdlopen (modname, RTLD_LAZY);
> + printf ("open %s\n", modname);
> +}
> +
> +static void
> +close_mod (void)
> +{
> + xdlclose (mod);
> + mod = NULL;
> + printf ("close %s\n", modname);
> +}
> +
> +static void
> +access_mod (const char *sym)
> +{
> + struct tls var = { -4, -4, -4, -4 };
> + struct tls *(*f) (struct tls *) = xdlsym (mod, sym);
> + /* Check that our malloc is called. */
> + malloc_counter = 0;
> + struct tls *p = f (&var);
> + TEST_VERIFY (malloc_counter != 0);
> + printf ("access %s: %s() = %p\n", modname, sym, p);
> + TEST_VERIFY_EXIT (memcmp (p, &var, sizeof (var)) == 0);
> + ++(p->a);
> +}
> +
> +static void *
> +start (void *arg)
> +{
> + access_mod ("apply_tls");
> + return arg;
> +}
> +
> +static int
> +do_test (void)
> +{
> + if (!IS_SUPPORTED ())
> + return EXIT_UNSUPPORTED;
> +
> + open_mod ();
> + pthread_t t = xpthread_create (NULL, start, NULL);
> + xpthread_join (t);
> + close_mod ();
> +
> + return 0;
> +}
> +
> +#include <support/test-driver.c>
> diff --git a/sysdeps/x86_64/dl-trampoline-save.h b/elf/tst-tls23.h
> similarity index 52%
> rename from sysdeps/x86_64/dl-trampoline-save.h
> rename to elf/tst-tls23.h
> index 761128d980..d0e734569c 100644
> --- a/sysdeps/x86_64/dl-trampoline-save.h
> +++ b/elf/tst-tls23.h
> @@ -1,5 +1,5 @@
> -/* x86-64 PLT trampoline register save macros.
> - Copyright (C) 2024-2025 Free Software Foundation, Inc.
> +/* Test that __tls_get_addr preserves caller-saved registers.
> + Copyright (C) 2025 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
> @@ -16,19 +16,25 @@
> License along with the GNU C Library; if not, see
> <https://www.gnu.org/licenses/>. */
>
> -#ifndef DL_STACK_ALIGNMENT
> -/* Due to GCC bug:
> +#include <stdint.h>
>
> - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58066
> +struct tls
> +{
> + int64_t a, b, c, d;
> +};
>
> - __tls_get_addr may be called with 8-byte stack alignment. Although
> - this bug has been fixed in GCC 4.9.4, 5.3 and 6, we can't assume
> - that stack will be always aligned at 16 bytes. */
> -# define DL_STACK_ALIGNMENT 8
> +extern struct tls *apply_tls (struct tls *);
> +
> +/* An architecture can define them to verify that caller-saved registers
> + aren't changed by __tls_get_addr. */
> +#ifndef INIT_TLS_CALL
> +# define INIT_TLS_CALL()
> +#endif
> +
> +#ifndef BEFORE_TLS_CALL
> +# define BEFORE_TLS_CALL()
> #endif
>
> -/* True if _dl_runtime_resolve should align stack for STATE_SAVE or align
> - stack to 16 bytes before calling _dl_fixup. */
> -#define DL_RUNTIME_RESOLVE_REALIGN_STACK \
> - (STATE_SAVE_ALIGNMENT > DL_STACK_ALIGNMENT \
> - || 16 > DL_STACK_ALIGNMENT)
> +#ifndef AFTER_TLS_CALL
> +# define AFTER_TLS_CALL()
> +#endif
> diff --git a/sysdeps/aarch64/preconfigure b/sysdeps/aarch64/preconfigure
> index 19657b627b..e1b772c586 100644
> --- a/sysdeps/aarch64/preconfigure
> +++ b/sysdeps/aarch64/preconfigure
> @@ -3,5 +3,6 @@ aarch64*)
> base_machine=aarch64
> machine=aarch64
> mtls_descriptor=desc
> + mtls_traditional=trad
> ;;
> esac
> diff --git a/sysdeps/i386/Makefile b/sysdeps/i386/Makefile
> index a2e8c0b128..ee6470d78e 100644
> --- a/sysdeps/i386/Makefile
> +++ b/sysdeps/i386/Makefile
> @@ -30,7 +30,9 @@ stack-align-test-flags += -malign-double
> endif
>
> ifeq ($(subdir),elf)
> -sysdep-dl-routines += tlsdesc dl-tlsdesc
> +sysdep-dl-routines += \
> + dl-tls-get-addr \
> +# sysdep-dl-routines
>
> tests += tst-audit3
> modules-names += tst-auditmod3a tst-auditmod3b
> diff --git a/sysdeps/i386/dl-tls-get-addr.c b/sysdeps/i386/dl-tls-get-addr.c
> new file mode 100644
> index 0000000000..c97e5c57be
> --- /dev/null
> +++ b/sysdeps/i386/dl-tls-get-addr.c
> @@ -0,0 +1,68 @@
> +/* Ifunc selector for ___tls_get_addr.
> + Copyright (C) 2025 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/>. */
> +
> +#ifdef SHARED
> +# define ___tls_get_addr __redirect____tls_get_addr
> +# include <dl-tls.h>
> +# undef ___tls_get_addr
> +# undef __tls_get_addr
> +
> +# define SYMBOL_NAME ___tls_get_addr
> +# include <init-arch.h>
> +
> +extern __typeof (REDIRECT_NAME) OPTIMIZE (fnsave) attribute_hidden;
> +extern __typeof (REDIRECT_NAME) OPTIMIZE (fxsave) attribute_hidden;
> +extern __typeof (REDIRECT_NAME) OPTIMIZE (xsave) attribute_hidden;
> +extern __typeof (REDIRECT_NAME) OPTIMIZE (xsavec) attribute_hidden;
> +
> +static inline void *
> +IFUNC_SELECTOR (void)
> +{
> + const struct cpu_features* cpu_features = __get_cpu_features ();
> +
> + if (cpu_features->xsave_state_size != 0)
> + {
> + if (CPU_FEATURE_USABLE_P (cpu_features, XSAVEC))
> + return OPTIMIZE (xsavec);
> + else
> + return OPTIMIZE (xsave);
> + }
> + else if (CPU_FEATURE_USABLE_P (cpu_features, FXSR))
> + return OPTIMIZE (fxsave);
> + return OPTIMIZE (fnsave);
> +}
> +
> +libc_ifunc_redirected (__redirect____tls_get_addr, ___tls_get_addr,
> + IFUNC_SELECTOR ());
> +
> +/* The special thing about the x86 TLS ABI is that we have two
> + variants of the __tls_get_addr function with different calling
> + conventions. The GNU version, which we are mostly concerned here,
> + takes the parameter in a register. The name is changed by adding
> + an additional underscore at the beginning. The Sun version uses
> + the normal calling convention. */
> +
> +rtld_hidden_proto (___tls_get_addr)
> +rtld_hidden_def (___tls_get_addr)
> +
> +void *
> +__tls_get_addr (tls_index *ti)
> +{
> + return ___tls_get_addr (ti);
> +}
> +#endif
> diff --git a/sysdeps/i386/dl-tls.h b/sysdeps/i386/dl-tls.h
> index f453931d78..ef605c5b0d 100644
> --- a/sysdeps/i386/dl-tls.h
> +++ b/sysdeps/i386/dl-tls.h
> @@ -37,34 +37,14 @@ typedef struct dl_tls_index
> /* This is the prototype for the GNU version. */
> extern void *___tls_get_addr (tls_index *ti)
> __attribute__ ((__regparm__ (1)));
> -extern void *___tls_get_addr_internal (tls_index *ti)
> - __attribute__ ((__regparm__ (1))) attribute_hidden;
> -
> # if IS_IN (rtld)
> -/* The special thing about the x86 TLS ABI is that we have two
> - variants of the __tls_get_addr function with different calling
> - conventions. The GNU version, which we are mostly concerned here,
> - takes the parameter in a register. The name is changed by adding
> - an additional underscore at the beginning. The Sun version uses
> - the normal calling convention. */
> -void *
> -__tls_get_addr (tls_index *ti)
> -{
> - return ___tls_get_addr_internal (ti);
> -}
> -
> -
> /* Prepare using the definition of __tls_get_addr in the generic
> version of this file. */
> -# define __tls_get_addr __attribute__ ((__regparm__ (1))) ___tls_get_addr
> -strong_alias (___tls_get_addr, ___tls_get_addr_internal)
> -rtld_hidden_proto (___tls_get_addr)
> -rtld_hidden_def (___tls_get_addr)
> -#else
> -
> +# define __tls_get_addr \
> + __attribute__ ((__regparm__ (1))) ___tls_get_addr_internal
> +# else
> /* Users should get the better interface. */
> -# define __tls_get_addr ___tls_get_addr
> -
> +# define __tls_get_addr ___tls_get_addr
> # endif
> #endif
>
> diff --git a/sysdeps/i386/dl-tlsdesc-dynamic.h b/sysdeps/i386/dl-tlsdesc-dynamic.h
> index 6aec06d15c..be9ecd659b 100644
> --- a/sysdeps/i386/dl-tlsdesc-dynamic.h
> +++ b/sysdeps/i386/dl-tlsdesc-dynamic.h
> @@ -16,34 +16,6 @@
> License along with the GNU C Library; if not, see
> <https://www.gnu.org/licenses/>. */
>
> -#undef REGISTER_SAVE_AREA
> -
> -#if !defined USE_FNSAVE && (STATE_SAVE_ALIGNMENT % 16) != 0
> -# error STATE_SAVE_ALIGNMENT must be multiple of 16
> -#endif
> -
> -#if DL_RUNTIME_RESOLVE_REALIGN_STACK
> -# ifdef USE_FNSAVE
> -# error USE_FNSAVE shouldn't be defined
> -# endif
> -# ifdef USE_FXSAVE
> -/* Use fxsave to save all registers. */
> -# define REGISTER_SAVE_AREA 512
> -# endif
> -#else
> -# ifdef USE_FNSAVE
> -/* Use fnsave to save x87 FPU stack registers. */
> -# define REGISTER_SAVE_AREA 108
> -# else
> -# ifndef USE_FXSAVE
> -# error USE_FXSAVE must be defined
> -# endif
> -/* Use fxsave to save all registers. Add 12 bytes to align the stack
> - to 16 bytes. */
> -# define REGISTER_SAVE_AREA (512 + 12)
> -# endif
> -#endif
> -
> .hidden _dl_tlsdesc_dynamic
> .global _dl_tlsdesc_dynamic
> .type _dl_tlsdesc_dynamic,@function
> @@ -104,85 +76,7 @@ _dl_tlsdesc_dynamic:
> ret
> .p2align 4,,7
> 2:
> - cfi_adjust_cfa_offset (32)
> -#if DL_RUNTIME_RESOLVE_REALIGN_STACK
> - movl %ebx, -28(%esp)
> - movl %esp, %ebx
> - cfi_def_cfa_register(%ebx)
> - and $-STATE_SAVE_ALIGNMENT, %esp
> -#endif
> -#ifdef REGISTER_SAVE_AREA
> - subl $REGISTER_SAVE_AREA, %esp
> -# if !DL_RUNTIME_RESOLVE_REALIGN_STACK
> - cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
> -# endif
> -#else
> -# if !DL_RUNTIME_RESOLVE_REALIGN_STACK
> -# error DL_RUNTIME_RESOLVE_REALIGN_STACK must be true
> -# endif
> - /* Allocate stack space of the required size to save the state. */
> - LOAD_PIC_REG (cx)
> - subl RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET+XSAVE_STATE_SIZE_OFFSET+_rtld_local_ro@GOTOFF(%ecx), %esp
> -#endif
> -#ifdef USE_FNSAVE
> - fnsave (%esp)
> -#elif defined USE_FXSAVE
> - fxsave (%esp)
> -#else
> - /* Save the argument for ___tls_get_addr in EAX. */
> - movl %eax, %ecx
> - movl $TLSDESC_CALL_STATE_SAVE_MASK, %eax
> - xorl %edx, %edx
> - /* Clear the XSAVE Header. */
> -# ifdef USE_XSAVE
> - movl %edx, (512)(%esp)
> - movl %edx, (512 + 4 * 1)(%esp)
> - movl %edx, (512 + 4 * 2)(%esp)
> - movl %edx, (512 + 4 * 3)(%esp)
> -# endif
> - movl %edx, (512 + 4 * 4)(%esp)
> - movl %edx, (512 + 4 * 5)(%esp)
> - movl %edx, (512 + 4 * 6)(%esp)
> - movl %edx, (512 + 4 * 7)(%esp)
> - movl %edx, (512 + 4 * 8)(%esp)
> - movl %edx, (512 + 4 * 9)(%esp)
> - movl %edx, (512 + 4 * 10)(%esp)
> - movl %edx, (512 + 4 * 11)(%esp)
> - movl %edx, (512 + 4 * 12)(%esp)
> - movl %edx, (512 + 4 * 13)(%esp)
> - movl %edx, (512 + 4 * 14)(%esp)
> - movl %edx, (512 + 4 * 15)(%esp)
> -# ifdef USE_XSAVE
> - xsave (%esp)
> -# else
> - xsavec (%esp)
> -# endif
> - /* Restore the argument for ___tls_get_addr in EAX. */
> - movl %ecx, %eax
> -#endif
> - call HIDDEN_JUMPTARGET (___tls_get_addr)
> - /* Get register content back. */
> -#ifdef USE_FNSAVE
> - frstor (%esp)
> -#elif defined USE_FXSAVE
> - fxrstor (%esp)
> -#else
> - /* Save and retore ___tls_get_addr return value stored in EAX. */
> - movl %eax, %ecx
> - movl $TLSDESC_CALL_STATE_SAVE_MASK, %eax
> - xorl %edx, %edx
> - xrstor (%esp)
> - movl %ecx, %eax
> -#endif
> -#if DL_RUNTIME_RESOLVE_REALIGN_STACK
> - mov %ebx, %esp
> - cfi_def_cfa_register(%esp)
> - movl -28(%esp), %ebx
> - cfi_restore(%ebx)
> -#else
> - addl $REGISTER_SAVE_AREA, %esp
> - cfi_adjust_cfa_offset(-REGISTER_SAVE_AREA)
> -#endif
> +#include "tls-get-addr-wrapper.h"
> jmp 1b
> cfi_endproc
> .size _dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic
> diff --git a/sysdeps/i386/dl-tlsdesc.S b/sysdeps/i386/dl-tlsdesc.S
> index c080993a60..c914ca4220 100644
> --- a/sysdeps/i386/dl-tlsdesc.S
> +++ b/sysdeps/i386/dl-tlsdesc.S
> @@ -22,23 +22,6 @@
> #include <features-offsets.h>
> #include "tlsdesc.h"
>
> -#ifndef DL_STACK_ALIGNMENT
> -/* Due to GCC bug:
> -
> - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58066
> -
> - __tls_get_addr may be called with 4-byte stack alignment. Although
> - this bug has been fixed in GCC 4.9.4, 5.3 and 6, we can't assume
> - that stack will be always aligned at 16 bytes. */
> -# define DL_STACK_ALIGNMENT 4
> -#endif
> -
> -/* True if _dl_tlsdesc_dynamic should align stack for STATE_SAVE or align
> - stack to MINIMUM_ALIGNMENT bytes before calling ___tls_get_addr. */
> -#define DL_RUNTIME_RESOLVE_REALIGN_STACK \
> - (STATE_SAVE_ALIGNMENT > DL_STACK_ALIGNMENT \
> - || MINIMUM_ALIGNMENT > DL_STACK_ALIGNMENT)
> -
> .text
>
> /* This function is used to compute the TP offset for symbols in
> diff --git a/sysdeps/i386/tls-get-addr-wrapper.h b/sysdeps/i386/tls-get-addr-wrapper.h
> new file mode 100644
> index 0000000000..0708e5ad1d
> --- /dev/null
> +++ b/sysdeps/i386/tls-get-addr-wrapper.h
> @@ -0,0 +1,127 @@
> +/* Wrapper of i386 ___tls_get_addr to save and restore vector registers.
> + Copyright (C) 2025 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/>. */
> +
> +#undef REGISTER_SAVE_AREA
> +
> +#if !defined USE_FNSAVE && (STATE_SAVE_ALIGNMENT % 16) != 0
> +# error STATE_SAVE_ALIGNMENT must be multiple of 16
> +#endif
> +
> +#if DL_RUNTIME_RESOLVE_REALIGN_STACK
> +# ifdef USE_FNSAVE
> +# error USE_FNSAVE shouldn't be defined
> +# endif
> +# ifdef USE_FXSAVE
> +/* Use fxsave to save all registers. */
> +# define REGISTER_SAVE_AREA 512
> +# endif
> +#else
> +# ifdef USE_FNSAVE
> +/* Use fnsave to save x87 FPU stack registers. */
> +# define REGISTER_SAVE_AREA 108
> +# else
> +# ifndef USE_FXSAVE
> +# error USE_FXSAVE must be defined
> +# endif
> +/* Use fxsave to save all registers. Add 12 bytes to align the stack
> + to 16 bytes. */
> +# define REGISTER_SAVE_AREA (512 + 12)
> +# endif
> +#endif
> +
> +#if DL_RUNTIME_RESOLVE_REALIGN_STACK
> + movl %ebx, 28(%esp)
> + movl %esp, %ebx
> + cfi_def_cfa_register(%ebx)
> + and $-STATE_SAVE_ALIGNMENT, %esp
> +#endif
> +#ifdef REGISTER_SAVE_AREA
> + subl $REGISTER_SAVE_AREA, %esp
> +# if !DL_RUNTIME_RESOLVE_REALIGN_STACK
> + cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
> +# endif
> +#else
> +# if !DL_RUNTIME_RESOLVE_REALIGN_STACK
> +# error DL_RUNTIME_RESOLVE_REALIGN_STACK must be true
> +# endif
> + /* Allocate stack space of the required size to save the state. */
> + LOAD_PIC_REG (cx)
> + subl RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET \
> + +XSAVE_STATE_SIZE_OFFSET+_rtld_local_ro@GOTOFF(%ecx), %esp
> +#endif
> +#ifdef USE_FNSAVE
> + fnsave (%esp)
> +#elif defined USE_FXSAVE
> + fxsave (%esp)
> +#else
> + /* Save the argument for ___tls_get_addr in EAX. */
> + movl %eax, %ecx
> + movl $TLSDESC_CALL_STATE_SAVE_MASK, %eax
> + xorl %edx, %edx
> + /* Clear the XSAVE Header. */
> +# ifdef USE_XSAVE
> + movl %edx, (512)(%esp)
> + movl %edx, (512 + 4 * 1)(%esp)
> + movl %edx, (512 + 4 * 2)(%esp)
> + movl %edx, (512 + 4 * 3)(%esp)
> +# endif
> + movl %edx, (512 + 4 * 4)(%esp)
> + movl %edx, (512 + 4 * 5)(%esp)
> + movl %edx, (512 + 4 * 6)(%esp)
> + movl %edx, (512 + 4 * 7)(%esp)
> + movl %edx, (512 + 4 * 8)(%esp)
> + movl %edx, (512 + 4 * 9)(%esp)
> + movl %edx, (512 + 4 * 10)(%esp)
> + movl %edx, (512 + 4 * 11)(%esp)
> + movl %edx, (512 + 4 * 12)(%esp)
> + movl %edx, (512 + 4 * 13)(%esp)
> + movl %edx, (512 + 4 * 14)(%esp)
> + movl %edx, (512 + 4 * 15)(%esp)
> +# ifdef USE_XSAVE
> + xsave (%esp)
> +# else
> + xsavec (%esp)
> +# endif
> + /* Restore the argument for ___tls_get_addr in EAX. */
> + movl %ecx, %eax
> +#endif
> + call ___tls_get_addr_internal
> + /* Get register content back. */
> +#ifdef USE_FNSAVE
> + frstor (%esp)
> +#elif defined USE_FXSAVE
> + fxrstor (%esp)
> +#else
> + /* Save and retore ___tls_get_addr return value stored in EAX. */
> + movl %eax, %ecx
> + movl $TLSDESC_CALL_STATE_SAVE_MASK, %eax
> + xorl %edx, %edx
> + xrstor (%esp)
> + movl %ecx, %eax
> +#endif
> +#if DL_RUNTIME_RESOLVE_REALIGN_STACK
> + mov %ebx, %esp
> + cfi_def_cfa_register(%esp)
> + movl 28(%esp), %ebx
> + cfi_restore(%ebx)
> +#else
> + addl $REGISTER_SAVE_AREA, %esp
> + cfi_adjust_cfa_offset(-REGISTER_SAVE_AREA)
> +#endif
> +
> +#undef STATE_SAVE_ALIGNMENT
> diff --git a/sysdeps/i386/tls_get_addr.S b/sysdeps/i386/tls_get_addr.S
> new file mode 100644
> index 0000000000..7d143d8a23
> --- /dev/null
> +++ b/sysdeps/i386/tls_get_addr.S
> @@ -0,0 +1,57 @@
> +/* Thread-local storage handling in the ELF dynamic linker. i386 version.
> + Copyright (C) 2025 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>
> +
> + .text
> +#ifdef SHARED
> +# define USE_FNSAVE
> +# define MINIMUM_ALIGNMENT 4
> +# define STATE_SAVE_ALIGNMENT 4
> +# define ___tls_get_addr _____tls_get_addr_fnsave
> +# include "tls_get_addr.h"
> +# undef ___tls_get_addr
> +# undef MINIMUM_ALIGNMENT
> +# undef USE_FNSAVE
> +
> +# define MINIMUM_ALIGNMENT 16
> +
> +# define USE_FXSAVE
> +# define STATE_SAVE_ALIGNMENT 16
> +# define ___tls_get_addr _____tls_get_addr_fxsave
> +# include "tls_get_addr.h"
> +# undef ___tls_get_addr
> +# undef USE_FXSAVE
> +
> +# define USE_XSAVE
> +# define STATE_SAVE_ALIGNMENT 64
> +# define ___tls_get_addr _____tls_get_addr_xsave
> +# include "tls_get_addr.h"
> +# undef ___tls_get_addr
> +# undef USE_XSAVE
> +
> +# define USE_XSAVEC
> +# define STATE_SAVE_ALIGNMENT 64
> +# define ___tls_get_addr _____tls_get_addr_xsavec
> +# include "tls_get_addr.h"
> +# undef ___tls_get_addr
> +# undef USE_XSAVEC
> +#endif /* SHARED */
> diff --git a/sysdeps/i386/tls_get_addr.h b/sysdeps/i386/tls_get_addr.h
> new file mode 100644
> index 0000000000..1825798724
> --- /dev/null
> +++ b/sysdeps/i386/tls_get_addr.h
> @@ -0,0 +1,42 @@
> +/* Thread-local storage handling in the ELF dynamic linker. i386 version.
> + Copyright (C) 2025 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/>. */
> +
> + .hidden ___tls_get_addr
> + .global ___tls_get_addr
> + .type ___tls_get_addr,@function
> +
> + /* This function is a wrapper of ___tls_get_addr_internal to
> + preserve caller-saved vector registers. */
> +
> + cfi_startproc
> + .align 16
> +___tls_get_addr:
> + /* Like all TLS resolvers, preserve call-clobbered registers.
> + We need two scratch regs anyway. */
> + subl $32, %esp
> + cfi_adjust_cfa_offset (32)
> + movl %ecx, 20(%esp)
> + movl %edx, 24(%esp)
> +#include "tls-get-addr-wrapper.h"
> + movl 20(%esp), %ecx
> + movl 24(%esp), %edx
> + addl $32, %esp
> + cfi_adjust_cfa_offset (-32)
> + ret
> + cfi_endproc
> + .size ___tls_get_addr, .-___tls_get_addr
> diff --git a/sysdeps/loongarch/preconfigure b/sysdeps/loongarch/preconfigure
> index 0d1e9ed8df..6726ab8302 100644
> --- a/sysdeps/loongarch/preconfigure
> +++ b/sysdeps/loongarch/preconfigure
> @@ -44,6 +44,7 @@ loongarch*)
>
> base_machine=loongarch
> mtls_descriptor=desc
> + mtls_traditional=trad
> ;;
> esac
>
> diff --git a/sysdeps/loongarch/preconfigure.ac b/sysdeps/loongarch/preconfigure.ac
> index df07dbf41f..56402261df 100644
> --- a/sysdeps/loongarch/preconfigure.ac
> +++ b/sysdeps/loongarch/preconfigure.ac
> @@ -42,6 +42,7 @@ loongarch*)
>
> base_machine=loongarch
> mtls_descriptor=desc
> + mtls_traditional=trad
> ;;
> esac
>
> diff --git a/sysdeps/powerpc/Makefile b/sysdeps/powerpc/Makefile
> index 5e6cb07ce6..5cdb64f29b 100644
> --- a/sysdeps/powerpc/Makefile
> +++ b/sysdeps/powerpc/Makefile
> @@ -28,6 +28,11 @@ tst-cache-ppc-static-dlopen-ENV = LD_LIBRARY_PATH=$(objpfx):$(common-objpfx):$(c
> $(objpfx)tst-cache-ppc-static-dlopen.out: $(objpfx)mod-cache-ppc.so
>
> $(objpfx)tst-cache-ppc: $(objpfx)mod-cache-ppc.so
> +
> +# The test checks if the __tls_get_addr does not clobber caller-saved
> +# register, so disable the powerpc specific optimization to force a
> +# __tls_get_addr call.
> +LDFLAGS-tst-tls23-mod.so = -Wl,--no-tls-get-addr-optimize
> endif
>
> ifneq (no,$(multi-arch))
> diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile
> index 01b0192ddf..f64cee3cd9 100644
> --- a/sysdeps/x86/Makefile
> +++ b/sysdeps/x86/Makefile
> @@ -4,7 +4,13 @@ endif
>
> ifeq ($(subdir),elf)
> sysdep_routines += get-cpuid-feature-leaf
> -sysdep-dl-routines += dl-get-cpu-features
> +sysdep-dl-routines += \
> + dl-get-cpu-features \
> + dl-tlsdesc \
> + tls_get_addr \
> + tlsdesc \
> +# sysdep-dl-routines
> +
> sysdep_headers += \
> bits/platform/features.h \
> bits/platform/x86.h \
> @@ -113,6 +119,14 @@ $(objpfx)tst-gnu2-tls2-x86-noxsavexsavec.out: \
> $(objpfx)tst-gnu2-tls2mod0.so \
> $(objpfx)tst-gnu2-tls2mod1.so \
> $(objpfx)tst-gnu2-tls2mod2.so
> +
> +CFLAGS-tst-tls23.c += -msse2
> +CFLAGS-tst-tls23-mod.c += -msse2 -mtune=haswell
> +
> +LDFLAGS-tst-tls23 += -rdynamic
> +tst-tls23-mod.so-no-z-defs = yes
> +
> +$(objpfx)tst-tls23-mod.so: $(libsupport)
> endif
>
> ifeq ($(subdir),math)
> diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h
> index c3c73e75dd..b8e963b654 100644
> --- a/sysdeps/x86/sysdep.h
> +++ b/sysdeps/x86/sysdep.h
> @@ -183,6 +183,29 @@
>
> #define atom_text_section .section ".text.atom", "ax"
>
> +#ifndef DL_STACK_ALIGNMENT
> +/* Due to GCC bug:
> +
> + https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58066
> +
> + __tls_get_addr may be called with 8-byte/4-byte stack alignment.
> + Although this bug has been fixed in GCC 4.9.4, 5.3 and 6, we can't
> + assume that stack will be always aligned at 16 bytes. */
> +# ifdef __x86_64__
> +# define DL_STACK_ALIGNMENT 8
> +# define MINIMUM_ALIGNMENT 16
> +# else
> +# define DL_STACK_ALIGNMENT 4
> +# endif
> +#endif
> +
> +/* True if _dl_runtime_resolve/_dl_tlsdesc_dynamic should align stack for
> + STATE_SAVE or align stack to MINIMUM_ALIGNMENT bytes before calling
> + _dl_fixup/__tls_get_addr. */
> +#define DL_RUNTIME_RESOLVE_REALIGN_STACK \
> + (STATE_SAVE_ALIGNMENT > DL_STACK_ALIGNMENT \
> + || MINIMUM_ALIGNMENT > DL_STACK_ALIGNMENT)
> +
> #endif /* __ASSEMBLER__ */
>
> #endif /* _X86_SYSDEP_H */
> diff --git a/sysdeps/x86/tst-tls23.c b/sysdeps/x86/tst-tls23.c
> new file mode 100644
> index 0000000000..6130d91cf8
> --- /dev/null
> +++ b/sysdeps/x86/tst-tls23.c
> @@ -0,0 +1,22 @@
> +#ifndef __x86_64__
> +#include <sys/platform/x86.h>
> +
> +#define IS_SUPPORTED() CPU_FEATURE_ACTIVE (SSE2)
> +#endif
> +
> +/* Set XMM0...XMM7 to all 1s. */
> +#define PREPARE_MALLOC() \
> +{ \
> + asm volatile ("pcmpeqd %%xmm0, %%xmm0" : : : "xmm0" ); \
> + asm volatile ("pcmpeqd %%xmm1, %%xmm1" : : : "xmm1" ); \
> + asm volatile ("pcmpeqd %%xmm2, %%xmm2" : : : "xmm2" ); \
> + asm volatile ("pcmpeqd %%xmm3, %%xmm3" : : : "xmm3" ); \
> + asm volatile ("pcmpeqd %%xmm4, %%xmm4" : : : "xmm4" ); \
> + asm volatile ("pcmpeqd %%xmm5, %%xmm5" : : : "xmm5" ); \
> + asm volatile ("pcmpeqd %%xmm6, %%xmm6" : : : "xmm6" ); \
> + asm volatile ("pcmpeqd %%xmm7, %%xmm7" : : : "xmm7" ); \
> +}
> +
> +#include <elf/tst-tls23.c>
> +
> +v2di v1, v2, v3;
> diff --git a/sysdeps/x86/tst-tls23.h b/sysdeps/x86/tst-tls23.h
> new file mode 100644
> index 0000000000..21cee4ca07
> --- /dev/null
> +++ b/sysdeps/x86/tst-tls23.h
> @@ -0,0 +1,35 @@
> +/* Test that __tls_get_addr preserves XMM registers.
> + Copyright (C) 2025 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 <support/check.h>
> +
> +typedef long long v2di __attribute__((vector_size(16)));
> +extern v2di v1, v2, v3;
> +
> +#define BEFORE_TLS_CALL() \
> + v1 = __extension__(v2di){0, 0}; \
> + v2 = __extension__(v2di){0, 0};
> +
> +#define AFTER_TLS_CALL() \
> + v3 = __extension__(v2di){0, 0}; \
> + asm volatile ("" : "+x" (v3)); \
> + union { v2di x; long long a[2]; } u; \
> + u.x = v3; \
> + TEST_VERIFY_EXIT (u.a[0] == 0 && u.a[1] == 0);
> +
> +#include <elf/tst-tls23.h>
> diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
> index e8f8a52eea..be64eb2ee4 100644
> --- a/sysdeps/x86_64/Makefile
> +++ b/sysdeps/x86_64/Makefile
> @@ -41,9 +41,6 @@ ifeq ($(subdir),elf)
> CFLAGS-.os += $(if $(filter $(@F),$(patsubst %,%.os,$(all-rtld-routines))),\
> -mno-mmx)
>
> -sysdep-dl-routines += tlsdesc dl-tlsdesc tls_get_addr
> -
> -tests += ifuncmain8
> modules-names += ifuncmod8
>
> $(objpfx)ifuncmain8: $(objpfx)ifuncmod8.so
> diff --git a/sysdeps/x86_64/dl-tlsdesc.S b/sysdeps/x86_64/dl-tlsdesc.S
> index d1bb125560..9a55fc52bb 100644
> --- a/sysdeps/x86_64/dl-tlsdesc.S
> +++ b/sysdeps/x86_64/dl-tlsdesc.S
> @@ -22,7 +22,6 @@
> #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. */
> diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
> index a055722e64..ac85f96794 100644
> --- a/sysdeps/x86_64/dl-trampoline.S
> +++ b/sysdeps/x86_64/dl-trampoline.S
> @@ -22,7 +22,6 @@
> #include <features-offsets.h>
> #include <link-defines.h>
> #include <isa-level.h>
> -#include "dl-trampoline-save.h"
>
> /* Area on stack to save and restore registers used for parameter
> passing when calling _dl_fixup. */
> --
> 2.49.0
>
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