[v2] libgcc: aarch64: Add SME runtime support

Message ID ZXL1MK1Bt7gCzwXx@arm.com
State Committed
Commit 328c17af772207cb03740809c05ba2c3abfb86be
Headers
Series [v2] libgcc: aarch64: Add SME runtime support |

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Commit Message

Szabolcs Nagy Dec. 8, 2023, 10:51 a.m. UTC
  The call ABI for SME (Scalable Matrix Extension) requires a number of
helper routines which are added to libgcc so they are tied to the
compiler version instead of the libc version. See
https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst#sme-support-routines

The routines are in shared libgcc and static libgcc eh, even though
they are not related to exception handling.  This is to avoid linking
a copy of the routines into dynamic linked binaries, because TPIDR2_EL0
block can be extended in the future which is better to handle in a
single place per process.

The support routines have to decide if SME is accessible or not. Linux
tells userspace if SME is accessible via AT_HWCAP2, otherwise a new
__aarch64_sme_accessible symbol was introduced that a libc can define.
Due to libgcc and libc build order, the symbol availability cannot be
checked so for __aarch64_sme_accessible an unistd.h feature test macro
is used while such detection mechanism is not available for __getauxval
so we rely on configure checks based on the target triplet.

Asm helper code is added to make writing the routines easier.

libgcc/ChangeLog:

	* config/aarch64/t-aarch64: Add sources to the build.
	* config/aarch64/__aarch64_have_sme.c: New file.
	* config/aarch64/__arm_sme_state.S: New file.
	* config/aarch64/__arm_tpidr2_restore.S: New file.
	* config/aarch64/__arm_tpidr2_save.S: New file.
	* config/aarch64/__arm_za_disable.S: New file.
	* config/aarch64/aarch64-asm.h: New file.
	* config/aarch64/libgcc-sme.ver: New file.
---
v2:
- do not include unistd.h when inhibit_libc is set.
- use msr tpidr2_el0,xzr in __arm_za_disable.

 libgcc/config/aarch64/__aarch64_have_sme.c   |  75 ++++++++++++++
 libgcc/config/aarch64/__arm_sme_state.S      |  55 ++++++++++
 libgcc/config/aarch64/__arm_tpidr2_restore.S |  89 ++++++++++++++++
 libgcc/config/aarch64/__arm_tpidr2_save.S    | 101 +++++++++++++++++++
 libgcc/config/aarch64/__arm_za_disable.S     |  65 ++++++++++++
 libgcc/config/aarch64/aarch64-asm.h          |  98 ++++++++++++++++++
 libgcc/config/aarch64/libgcc-sme.ver         |  24 +++++
 libgcc/config/aarch64/t-aarch64              |  10 ++
 8 files changed, 517 insertions(+)
 create mode 100644 libgcc/config/aarch64/__aarch64_have_sme.c
 create mode 100644 libgcc/config/aarch64/__arm_sme_state.S
 create mode 100644 libgcc/config/aarch64/__arm_tpidr2_restore.S
 create mode 100644 libgcc/config/aarch64/__arm_tpidr2_save.S
 create mode 100644 libgcc/config/aarch64/__arm_za_disable.S
 create mode 100644 libgcc/config/aarch64/aarch64-asm.h
 create mode 100644 libgcc/config/aarch64/libgcc-sme.ver
  

Comments

Richard Sandiford Dec. 8, 2023, 10:58 a.m. UTC | #1
Szabolcs Nagy <szabolcs.nagy@arm.com> writes:
> The call ABI for SME (Scalable Matrix Extension) requires a number of
> helper routines which are added to libgcc so they are tied to the
> compiler version instead of the libc version. See
> https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst#sme-support-routines
>
> The routines are in shared libgcc and static libgcc eh, even though
> they are not related to exception handling.  This is to avoid linking
> a copy of the routines into dynamic linked binaries, because TPIDR2_EL0
> block can be extended in the future which is better to handle in a
> single place per process.
>
> The support routines have to decide if SME is accessible or not. Linux
> tells userspace if SME is accessible via AT_HWCAP2, otherwise a new
> __aarch64_sme_accessible symbol was introduced that a libc can define.
> Due to libgcc and libc build order, the symbol availability cannot be
> checked so for __aarch64_sme_accessible an unistd.h feature test macro
> is used while such detection mechanism is not available for __getauxval
> so we rely on configure checks based on the target triplet.
>
> Asm helper code is added to make writing the routines easier.
>
> libgcc/ChangeLog:
>
> 	* config/aarch64/t-aarch64: Add sources to the build.
> 	* config/aarch64/__aarch64_have_sme.c: New file.
> 	* config/aarch64/__arm_sme_state.S: New file.
> 	* config/aarch64/__arm_tpidr2_restore.S: New file.
> 	* config/aarch64/__arm_tpidr2_save.S: New file.
> 	* config/aarch64/__arm_za_disable.S: New file.
> 	* config/aarch64/aarch64-asm.h: New file.
> 	* config/aarch64/libgcc-sme.ver: New file.
> ---
> v2:
> - do not include unistd.h when inhibit_libc is set.
> - use msr tpidr2_el0,xzr in __arm_za_disable.

LGTM, thanks.

>  libgcc/config/aarch64/__aarch64_have_sme.c   |  75 ++++++++++++++
>  libgcc/config/aarch64/__arm_sme_state.S      |  55 ++++++++++
>  libgcc/config/aarch64/__arm_tpidr2_restore.S |  89 ++++++++++++++++
>  libgcc/config/aarch64/__arm_tpidr2_save.S    | 101 +++++++++++++++++++
>  libgcc/config/aarch64/__arm_za_disable.S     |  65 ++++++++++++
>  libgcc/config/aarch64/aarch64-asm.h          |  98 ++++++++++++++++++
>  libgcc/config/aarch64/libgcc-sme.ver         |  24 +++++
>  libgcc/config/aarch64/t-aarch64              |  10 ++
>  8 files changed, 517 insertions(+)
>  create mode 100644 libgcc/config/aarch64/__aarch64_have_sme.c
>  create mode 100644 libgcc/config/aarch64/__arm_sme_state.S
>  create mode 100644 libgcc/config/aarch64/__arm_tpidr2_restore.S
>  create mode 100644 libgcc/config/aarch64/__arm_tpidr2_save.S
>  create mode 100644 libgcc/config/aarch64/__arm_za_disable.S
>  create mode 100644 libgcc/config/aarch64/aarch64-asm.h
>  create mode 100644 libgcc/config/aarch64/libgcc-sme.ver
>
> diff --git a/libgcc/config/aarch64/__aarch64_have_sme.c b/libgcc/config/aarch64/__aarch64_have_sme.c
> new file mode 100644
> index 00000000000..5e649246270
> --- /dev/null
> +++ b/libgcc/config/aarch64/__aarch64_have_sme.c
> @@ -0,0 +1,75 @@
> +/* Initializer for SME support.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of GCC.
> +
> +   GCC is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published
> +   by the Free Software Foundation; either version 3, or (at your
> +   option) any later version.
> +
> +   GCC 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 General Public
> +   License for more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include "auto-target.h"
> +
> +#ifndef inhibit_libc
> +/* For libc feature test macros.  */
> +# include <unistd.h>
> +#endif
> +
> +#if __ARM_FEATURE_SME
> +/* Avoid runtime SME detection if libgcc is built with SME.  */
> +# define HAVE_SME_CONST const
> +# define HAVE_SME_VALUE 1
> +#elif HAVE___GETAUXVAL
> +/* SME access detection on Linux.  */
> +# define HAVE_SME_CONST
> +# define HAVE_SME_VALUE 0
> +# define HAVE_SME_CTOR sme_accessible ()
> +
> +# define AT_HWCAP2	26
> +# define HWCAP2_SME	(1 << 23)
> +unsigned long int __getauxval (unsigned long int);
> +
> +static _Bool
> +sme_accessible (void)
> +{
> +  unsigned long hwcap2 = __getauxval (AT_HWCAP2);
> +  return (hwcap2 & HWCAP2_SME) != 0;
> +}
> +#elif __LIBC___AARCH64_SME_ACCESSIBLE
> +/* Alternative SME access detection.  */
> +# define HAVE_SME_CONST
> +# define HAVE_SME_VALUE 0
> +# define HAVE_SME_CTOR __aarch64_sme_accessible ()
> +_Bool __aarch64_sme_accessible (void);
> +#else
> +# define HAVE_SME_CONST const
> +# define HAVE_SME_VALUE 0
> +#endif
> +
> +/* Define the symbol gating SME support in libgcc.  */
> +HAVE_SME_CONST _Bool __aarch64_have_sme
> +  __attribute__((visibility("hidden"), nocommon)) = HAVE_SME_VALUE;
> +
> +#ifdef HAVE_SME_CTOR
> +/* Use a higher priority to ensure it runs before user constructors
> +   with priority 100. */
> +static void __attribute__((constructor (90)))
> +init_have_sme (void)
> +{
> +  __aarch64_have_sme = HAVE_SME_CTOR;
> +}
> +#endif
> diff --git a/libgcc/config/aarch64/__arm_sme_state.S b/libgcc/config/aarch64/__arm_sme_state.S
> new file mode 100644
> index 00000000000..c4e16cac00d
> --- /dev/null
> +++ b/libgcc/config/aarch64/__arm_sme_state.S
> @@ -0,0 +1,55 @@
> +/* Support routine for SME.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of GCC.
> +
> +   GCC is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published
> +   by the Free Software Foundation; either version 3, or (at your
> +   option) any later version.
> +
> +   GCC 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 General Public
> +   License for more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include "aarch64-asm.h"
> +
> +/* Query SME state.  Call ABI:
> +   - Private ZA, streaming-compatible.
> +   - x2-x15, x19-x29, sp and fp regs are call preserved.
> +   - Takes no argument.
> +   - Returns SME state in x0 and TPIDR2_EL0 in x1.  */
> +
> +.hidden __aarch64_have_sme
> +
> +variant_pcs (__arm_sme_state)
> +
> +ENTRY (__arm_sme_state)
> +	/* Check if SME is available.  */
> +	adrp	x1, __aarch64_have_sme
> +	ldrb	w1, [x1, :lo12:__aarch64_have_sme]
> +	cbz	w1, L(nosme)
> +
> +	/* Expose the bottom 2 bits of svcr (SM, ZA) in x0 and set the
> +	   top 2 bits indicating that SME and TPIDR2_EL0 are available.  */
> +	.inst	0xd53b4240  /* mrs	x0, svcr  */
> +	.inst	0xd53bd0a1  /* mrs	x1, tpidr2_el0  */
> +	and	x0, x0, 3
> +	orr	x0, x0, 0xc000000000000000
> +	ret
> +
> +L(nosme):
> +	mov	x0, 0
> +	mov	x1, 0
> +	ret
> +END (__arm_sme_state)
> diff --git a/libgcc/config/aarch64/__arm_tpidr2_restore.S b/libgcc/config/aarch64/__arm_tpidr2_restore.S
> new file mode 100644
> index 00000000000..4569d04a2d0
> --- /dev/null
> +++ b/libgcc/config/aarch64/__arm_tpidr2_restore.S
> @@ -0,0 +1,89 @@
> +/* Support routine for SME.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of GCC.
> +
> +   GCC is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published
> +   by the Free Software Foundation; either version 3, or (at your
> +   option) any later version.
> +
> +   GCC 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 General Public
> +   License for more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include "aarch64-asm.h"
> +
> +/* Used for lazy ZA restore.  Call ABI:
> +   - Shared ZA, streaming-compatible.
> +   - x0 is a pointer to a TPIDR2 block.
> +   - x0-x13, x19-x29, sp and fp regs are call preserved.
> +   - Does not return a value.
> +   - Can abort on failure (then registers are not preserved).  */
> +
> +variant_pcs (__arm_tpidr2_restore)
> +
> +ENTRY (__arm_tpidr2_restore)
> +	.inst	0xd53bd0ae  /* mrs	x14, tpidr2_el0  */
> +	cbnz	x14, L(fail)
> +
> +	/* check reserved bytes.  */
> +	ldrh	w15, [x0, 10]
> +	ldr	w16, [x0, 12]
> +	orr	w15, w15, w16
> +	cbnz	w15, L(fail)
> +
> +	ldr	x16, [x0]
> +	cbz	x16, L(end)
> +	ldrh	w17, [x0, 8]
> +	cbz	w17, L(end)
> +
> +	/* x0: blk, x14: 0, x15: 0,
> +	   x16: za_save_buffer, x17: num_za_save_slices.  */
> +
> +L(restore_loop):
> +	.inst	0xe1006200  /* ldr	za[w15, 0], [x16]  */
> +	.inst	0xe1006201  /* ldr	za[w15, 1], [x16, 1, mul vl]  */
> +	.inst	0xe1006202  /* ldr	za[w15, 2], [x16, 2, mul vl]  */
> +	.inst	0xe1006203  /* ldr	za[w15, 3], [x16, 3, mul vl]  */
> +	.inst	0xe1006204  /* ldr	za[w15, 4], [x16, 4, mul vl]  */
> +	.inst	0xe1006205  /* ldr	za[w15, 5], [x16, 5, mul vl]  */
> +	.inst	0xe1006206  /* ldr	za[w15, 6], [x16, 6, mul vl]  */
> +	.inst	0xe1006207  /* ldr	za[w15, 7], [x16, 7, mul vl]  */
> +	.inst	0xe1006208  /* ldr	za[w15, 8], [x16, 8, mul vl]  */
> +	.inst	0xe1006209  /* ldr	za[w15, 9], [x16, 9, mul vl]  */
> +	.inst	0xe100620a  /* ldr	za[w15, 10], [x16, 10, mul vl]  */
> +	.inst	0xe100620b  /* ldr	za[w15, 11], [x16, 11, mul vl]  */
> +	.inst	0xe100620c  /* ldr	za[w15, 12], [x16, 12, mul vl]  */
> +	.inst	0xe100620d  /* ldr	za[w15, 13], [x16, 13, mul vl]  */
> +	.inst	0xe100620e  /* ldr	za[w15, 14], [x16, 14, mul vl]  */
> +	.inst	0xe100620f  /* ldr	za[w15, 15], [x16, 15, mul vl]  */
> +	add	w15, w15, 16
> +	.inst	0x04305a10  /* addsvl	x16, x16, 16  */
> +	cmp	w17, w15
> +	bhi	L(restore_loop)
> +L(end):
> +	ret
> +L(fail):
> +	PACIASP
> +	stp	x29, x30, [sp, -32]!
> +	.cfi_adjust_cfa_offset 32
> +	.cfi_rel_offset x29, 0
> +	.cfi_rel_offset x30, 8
> +	mov	x29, sp
> +	.inst	0x04e0e3f0  /* cntd	x16  */
> +	str	x16, [sp, 16]
> +	.cfi_rel_offset 46, 16
> +	.inst	0xd503467f  /* smstop  */
> +	bl	abort
> +END (__arm_tpidr2_restore)
> diff --git a/libgcc/config/aarch64/__arm_tpidr2_save.S b/libgcc/config/aarch64/__arm_tpidr2_save.S
> new file mode 100644
> index 00000000000..879cf798079
> --- /dev/null
> +++ b/libgcc/config/aarch64/__arm_tpidr2_save.S
> @@ -0,0 +1,101 @@
> +/* Support routine for SME.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of GCC.
> +
> +   GCC is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published
> +   by the Free Software Foundation; either version 3, or (at your
> +   option) any later version.
> +
> +   GCC 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 General Public
> +   License for more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include "aarch64-asm.h"
> +
> +/* Used for lazy ZA save.  Call ABI:
> +   - Private ZA, streaming-compatible.
> +   - x0-x13, x19-x29, sp and fp regs are call preserved.
> +   - Takes no argument.
> +   - Does not return a value.
> +   - Can abort on failure (then registers are not preserved).  */
> +
> +.hidden __aarch64_have_sme
> +
> +variant_pcs (__arm_tpidr2_save)
> +
> +ENTRY (__arm_tpidr2_save)
> +	/* Check if SME is available.  */
> +	adrp	x14, __aarch64_have_sme
> +	ldrb	w14, [x14, :lo12:__aarch64_have_sme]
> +	cbz	w14, L(end)
> +
> +	.inst	0xd53bd0ae  /* mrs	x14, tpidr2_el0  */
> +	cbz	x14, L(end)
> +
> +	/* check reserved bytes.  */
> +	ldrh	w15, [x14, 10]
> +	ldr	w16, [x14, 12]
> +	orr	w15, w15, w16
> +	cbnz	w15, L(fail)
> +
> +	ldr	x16, [x14]
> +	cbz	x16, L(end)
> +	ldrh	w17, [x14, 8]
> +	cbz	w17, L(end)
> +
> +	/* x14: tpidr2, x15: 0,
> +	   x16: za_save_buffer, x17: num_za_save_slices.  */
> +
> +L(save_loop):
> +	.inst	0xe1206200  /* str	za[w15, 0], [x16]  */
> +	.inst	0xe1206201  /* str	za[w15, 1], [x16, 1, mul vl] */
> +	.inst	0xe1206202  /* str	za[w15, 2], [x16, 2, mul vl] */
> +	.inst	0xe1206203  /* str	za[w15, 3], [x16, 3, mul vl] */
> +	.inst	0xe1206204  /* str	za[w15, 4], [x16, 4, mul vl] */
> +	.inst	0xe1206205  /* str	za[w15, 5], [x16, 5, mul vl] */
> +	.inst	0xe1206206  /* str	za[w15, 6], [x16, 6, mul vl] */
> +	.inst	0xe1206207  /* str	za[w15, 7], [x16, 7, mul vl] */
> +	.inst	0xe1206208  /* str	za[w15, 8], [x16, 8, mul vl] */
> +	.inst	0xe1206209  /* str	za[w15, 9], [x16, 9, mul vl] */
> +	.inst	0xe120620a  /* str	za[w15, 10], [x16, 10, mul vl] */
> +	.inst	0xe120620b  /* str	za[w15, 11], [x16, 11, mul vl] */
> +	.inst	0xe120620c  /* str	za[w15, 12], [x16, 12, mul vl] */
> +	.inst	0xe120620d  /* str	za[w15, 13], [x16, 13, mul vl] */
> +	.inst	0xe120620e  /* str	za[w15, 14], [x16, 14, mul vl] */
> +	.inst	0xe120620f  /* str	za[w15, 15], [x16, 15, mul vl] */
> +	add	w15, w15, 16
> +	.inst	0x04305a10  /* addsvl	x16, x16, 16  */
> +	cmp	w17, w15
> +	bhi	L(save_loop)
> +L(end):
> +	ret
> +L(fail):
> +	PACIASP
> +	stp	x29, x30, [sp, -32]!
> +	.cfi_adjust_cfa_offset 32
> +	.cfi_rel_offset x29, 0
> +	.cfi_rel_offset x30, 8
> +	mov	x29, sp
> +	.inst	0x04e0e3f0  /* cntd	x16  */
> +	str	x16, [sp, 16]
> +	.cfi_rel_offset 46, 16
> +	.inst	0xd503467f  /* smstop  */
> +	bl	abort
> +END (__arm_tpidr2_save)
> +
> +/* Hidden alias used by __arm_za_disable.  */
> +.global __libgcc_arm_tpidr2_save
> +.hidden __libgcc_arm_tpidr2_save
> +.set __libgcc_arm_tpidr2_save, __arm_tpidr2_save
> diff --git a/libgcc/config/aarch64/__arm_za_disable.S b/libgcc/config/aarch64/__arm_za_disable.S
> new file mode 100644
> index 00000000000..cff5b9cec47
> --- /dev/null
> +++ b/libgcc/config/aarch64/__arm_za_disable.S
> @@ -0,0 +1,65 @@
> +/* Support routine for SME.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of GCC.
> +
> +   GCC is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published
> +   by the Free Software Foundation; either version 3, or (at your
> +   option) any later version.
> +
> +   GCC 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 General Public
> +   License for more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include "aarch64-asm.h"
> +
> +/* Disable ZA.  Call ABI:
> +   - Private ZA, streaming-compatible.
> +   - x0-x13, x19-x29, sp and fp regs are call preserved.
> +   - Takes no argument.
> +   - Does not return a value.
> +   - Can abort on failure (then registers are not preserved).  */
> +
> +.hidden __aarch64_have_sme
> +
> +.hidden __libgcc_arm_tpidr2_save
> +
> +variant_pcs (__arm_za_disable)
> +
> +ENTRY (__arm_za_disable)
> +	/* Check if SME is available.  */
> +	adrp	x14, __aarch64_have_sme
> +	ldrb	w14, [x14, :lo12:__aarch64_have_sme]
> +	cbz	w14, L(end)
> +
> +	.inst	0xd53bd0ae  /* mrs	x14, tpidr2_el0  */
> +	cbz	x14, L(end)
> +
> +	PACIASP
> +	stp	x29, x30, [sp, -16]!
> +	.cfi_adjust_cfa_offset 16
> +	.cfi_rel_offset x29, 0
> +	.cfi_rel_offset x30, 8
> +	mov	x29, sp
> +	bl	__libgcc_arm_tpidr2_save
> +	.inst	0xd51bd0bf  /* msr	tpidr2_el0, xzr  */
> +	.inst	0xd503447f  /* smstop	za  */
> +	ldp	x29, x30, [sp], 16
> +	.cfi_adjust_cfa_offset -16
> +	.cfi_restore x29
> +	.cfi_restore x30
> +	AUTIASP
> +L(end):
> +	ret
> +END (__arm_za_disable)
> diff --git a/libgcc/config/aarch64/aarch64-asm.h b/libgcc/config/aarch64/aarch64-asm.h
> new file mode 100644
> index 00000000000..8969b06b09c
> --- /dev/null
> +++ b/libgcc/config/aarch64/aarch64-asm.h
> @@ -0,0 +1,98 @@
> +/* AArch64 asm definitions.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of GCC.
> +
> +   GCC is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published
> +   by the Free Software Foundation; either version 3, or (at your
> +   option) any later version.
> +
> +   GCC 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 General Public
> +   License for more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include "auto-target.h"
> +
> +#define L(label) .L ## label
> +
> +/* Marking variant PCS symbol references is important for PLT calls
> +   otherwise it is for documenting the PCS in the symbol table.  */
> +#ifdef HAVE_AS_VARIANT_PCS
> +# define variant_pcs(name) .variant_pcs name
> +#else
> +# define variant_pcs(name)
> +#endif
> +
> +/* GNU_PROPERTY_AARCH64_* macros from elf.h for use in asm code.  */
> +#define FEATURE_1_AND 0xc0000000
> +#define FEATURE_1_BTI 1
> +#define FEATURE_1_PAC 2
> +
> +/* Supported features based on the code generation options.  */
> +#if defined(__ARM_FEATURE_BTI_DEFAULT)
> +# define BTI_FLAG FEATURE_1_BTI
> +# define BTI_C hint	34
> +#else
> +# define BTI_FLAG 0
> +# define BTI_C
> +#endif
> +
> +#if __ARM_FEATURE_PAC_DEFAULT & 3
> +# define PAC_FLAG FEATURE_1_PAC
> +# define PACIASP hint	25; .cfi_window_save
> +# define AUTIASP hint	29; .cfi_window_save
> +#else
> +# define PAC_FLAG 0
> +# define PACIASP
> +# define AUTIASP
> +#endif
> +
> +/* Add a NT_GNU_PROPERTY_TYPE_0 note.  */
> +#define GNU_PROPERTY(type, value)	\
> +  .section .note.gnu.property, "a";	\
> +  .p2align 3;				\
> +  .word 4;				\
> +  .word 16;				\
> +  .word 5;				\
> +  .asciz "GNU";				\
> +  .word type;				\
> +  .word 4;				\
> +  .word value;				\
> +  .word 0;				\
> +  .previous
> +
> +#if defined(__linux__) || defined(__FreeBSD__)
> +/* Do not require executable stack.  */
> +.section .note.GNU-stack, "", %progbits
> +.previous
> +
> +/* Add GNU property note if built with branch protection.  */
> +# if (BTI_FLAG|PAC_FLAG) != 0
> +GNU_PROPERTY (FEATURE_1_AND, BTI_FLAG|PAC_FLAG)
> +# endif
> +#endif
> +
> +#define ENTRY_ALIGN(name, align) \
> +  .global name;		\
> +  .type name,%function;	\
> +  .balign align;	\
> +  name:			\
> +  .cfi_startproc;	\
> +  BTI_C
> +
> +#define ENTRY(name) ENTRY_ALIGN(name, 16)
> +
> +#define END(name) \
> +  .cfi_endproc;		\
> +  .size name, .-name
> diff --git a/libgcc/config/aarch64/libgcc-sme.ver b/libgcc/config/aarch64/libgcc-sme.ver
> new file mode 100644
> index 00000000000..da889c6c09e
> --- /dev/null
> +++ b/libgcc/config/aarch64/libgcc-sme.ver
> @@ -0,0 +1,24 @@
> +# Copyright (C) 2023 Free Software Foundation, Inc.
> +#
> +# This file is part of GCC.
> +#
> +# GCC is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3, or (at your option)
> +# any later version.
> +#
> +# GCC 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 General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with GCC; see the file COPYING3.  If not see
> +# <http://www.gnu.org/licenses/>.
> +
> +GCC_14.0 {
> +  __arm_sme_state
> +  __arm_tpidr2_restore
> +  __arm_tpidr2_save
> +  __arm_za_disable
> +}
> diff --git a/libgcc/config/aarch64/t-aarch64 b/libgcc/config/aarch64/t-aarch64
> index a40b6241c86..7b852022a4d 100644
> --- a/libgcc/config/aarch64/t-aarch64
> +++ b/libgcc/config/aarch64/t-aarch64
> @@ -19,3 +19,13 @@
>  # <http://www.gnu.org/licenses/>.
>  
>  LIB2ADD += $(srcdir)/config/aarch64/sync-cache.c
> +
> +# Add sme runtime to shared libgcc
> +LIB2ADDEH += \
> +	$(srcdir)/config/aarch64/__aarch64_have_sme.c \
> +	$(srcdir)/config/aarch64/__arm_sme_state.S \
> +	$(srcdir)/config/aarch64/__arm_tpidr2_restore.S \
> +	$(srcdir)/config/aarch64/__arm_tpidr2_save.S \
> +	$(srcdir)/config/aarch64/__arm_za_disable.S
> +
> +SHLIB_MAPFILES += $(srcdir)/config/aarch64/libgcc-sme.ver
  

Patch

diff --git a/libgcc/config/aarch64/__aarch64_have_sme.c b/libgcc/config/aarch64/__aarch64_have_sme.c
new file mode 100644
index 00000000000..5e649246270
--- /dev/null
+++ b/libgcc/config/aarch64/__aarch64_have_sme.c
@@ -0,0 +1,75 @@ 
+/* Initializer for SME support.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "auto-target.h"
+
+#ifndef inhibit_libc
+/* For libc feature test macros.  */
+# include <unistd.h>
+#endif
+
+#if __ARM_FEATURE_SME
+/* Avoid runtime SME detection if libgcc is built with SME.  */
+# define HAVE_SME_CONST const
+# define HAVE_SME_VALUE 1
+#elif HAVE___GETAUXVAL
+/* SME access detection on Linux.  */
+# define HAVE_SME_CONST
+# define HAVE_SME_VALUE 0
+# define HAVE_SME_CTOR sme_accessible ()
+
+# define AT_HWCAP2	26
+# define HWCAP2_SME	(1 << 23)
+unsigned long int __getauxval (unsigned long int);
+
+static _Bool
+sme_accessible (void)
+{
+  unsigned long hwcap2 = __getauxval (AT_HWCAP2);
+  return (hwcap2 & HWCAP2_SME) != 0;
+}
+#elif __LIBC___AARCH64_SME_ACCESSIBLE
+/* Alternative SME access detection.  */
+# define HAVE_SME_CONST
+# define HAVE_SME_VALUE 0
+# define HAVE_SME_CTOR __aarch64_sme_accessible ()
+_Bool __aarch64_sme_accessible (void);
+#else
+# define HAVE_SME_CONST const
+# define HAVE_SME_VALUE 0
+#endif
+
+/* Define the symbol gating SME support in libgcc.  */
+HAVE_SME_CONST _Bool __aarch64_have_sme
+  __attribute__((visibility("hidden"), nocommon)) = HAVE_SME_VALUE;
+
+#ifdef HAVE_SME_CTOR
+/* Use a higher priority to ensure it runs before user constructors
+   with priority 100. */
+static void __attribute__((constructor (90)))
+init_have_sme (void)
+{
+  __aarch64_have_sme = HAVE_SME_CTOR;
+}
+#endif
diff --git a/libgcc/config/aarch64/__arm_sme_state.S b/libgcc/config/aarch64/__arm_sme_state.S
new file mode 100644
index 00000000000..c4e16cac00d
--- /dev/null
+++ b/libgcc/config/aarch64/__arm_sme_state.S
@@ -0,0 +1,55 @@ 
+/* Support routine for SME.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "aarch64-asm.h"
+
+/* Query SME state.  Call ABI:
+   - Private ZA, streaming-compatible.
+   - x2-x15, x19-x29, sp and fp regs are call preserved.
+   - Takes no argument.
+   - Returns SME state in x0 and TPIDR2_EL0 in x1.  */
+
+.hidden __aarch64_have_sme
+
+variant_pcs (__arm_sme_state)
+
+ENTRY (__arm_sme_state)
+	/* Check if SME is available.  */
+	adrp	x1, __aarch64_have_sme
+	ldrb	w1, [x1, :lo12:__aarch64_have_sme]
+	cbz	w1, L(nosme)
+
+	/* Expose the bottom 2 bits of svcr (SM, ZA) in x0 and set the
+	   top 2 bits indicating that SME and TPIDR2_EL0 are available.  */
+	.inst	0xd53b4240  /* mrs	x0, svcr  */
+	.inst	0xd53bd0a1  /* mrs	x1, tpidr2_el0  */
+	and	x0, x0, 3
+	orr	x0, x0, 0xc000000000000000
+	ret
+
+L(nosme):
+	mov	x0, 0
+	mov	x1, 0
+	ret
+END (__arm_sme_state)
diff --git a/libgcc/config/aarch64/__arm_tpidr2_restore.S b/libgcc/config/aarch64/__arm_tpidr2_restore.S
new file mode 100644
index 00000000000..4569d04a2d0
--- /dev/null
+++ b/libgcc/config/aarch64/__arm_tpidr2_restore.S
@@ -0,0 +1,89 @@ 
+/* Support routine for SME.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "aarch64-asm.h"
+
+/* Used for lazy ZA restore.  Call ABI:
+   - Shared ZA, streaming-compatible.
+   - x0 is a pointer to a TPIDR2 block.
+   - x0-x13, x19-x29, sp and fp regs are call preserved.
+   - Does not return a value.
+   - Can abort on failure (then registers are not preserved).  */
+
+variant_pcs (__arm_tpidr2_restore)
+
+ENTRY (__arm_tpidr2_restore)
+	.inst	0xd53bd0ae  /* mrs	x14, tpidr2_el0  */
+	cbnz	x14, L(fail)
+
+	/* check reserved bytes.  */
+	ldrh	w15, [x0, 10]
+	ldr	w16, [x0, 12]
+	orr	w15, w15, w16
+	cbnz	w15, L(fail)
+
+	ldr	x16, [x0]
+	cbz	x16, L(end)
+	ldrh	w17, [x0, 8]
+	cbz	w17, L(end)
+
+	/* x0: blk, x14: 0, x15: 0,
+	   x16: za_save_buffer, x17: num_za_save_slices.  */
+
+L(restore_loop):
+	.inst	0xe1006200  /* ldr	za[w15, 0], [x16]  */
+	.inst	0xe1006201  /* ldr	za[w15, 1], [x16, 1, mul vl]  */
+	.inst	0xe1006202  /* ldr	za[w15, 2], [x16, 2, mul vl]  */
+	.inst	0xe1006203  /* ldr	za[w15, 3], [x16, 3, mul vl]  */
+	.inst	0xe1006204  /* ldr	za[w15, 4], [x16, 4, mul vl]  */
+	.inst	0xe1006205  /* ldr	za[w15, 5], [x16, 5, mul vl]  */
+	.inst	0xe1006206  /* ldr	za[w15, 6], [x16, 6, mul vl]  */
+	.inst	0xe1006207  /* ldr	za[w15, 7], [x16, 7, mul vl]  */
+	.inst	0xe1006208  /* ldr	za[w15, 8], [x16, 8, mul vl]  */
+	.inst	0xe1006209  /* ldr	za[w15, 9], [x16, 9, mul vl]  */
+	.inst	0xe100620a  /* ldr	za[w15, 10], [x16, 10, mul vl]  */
+	.inst	0xe100620b  /* ldr	za[w15, 11], [x16, 11, mul vl]  */
+	.inst	0xe100620c  /* ldr	za[w15, 12], [x16, 12, mul vl]  */
+	.inst	0xe100620d  /* ldr	za[w15, 13], [x16, 13, mul vl]  */
+	.inst	0xe100620e  /* ldr	za[w15, 14], [x16, 14, mul vl]  */
+	.inst	0xe100620f  /* ldr	za[w15, 15], [x16, 15, mul vl]  */
+	add	w15, w15, 16
+	.inst	0x04305a10  /* addsvl	x16, x16, 16  */
+	cmp	w17, w15
+	bhi	L(restore_loop)
+L(end):
+	ret
+L(fail):
+	PACIASP
+	stp	x29, x30, [sp, -32]!
+	.cfi_adjust_cfa_offset 32
+	.cfi_rel_offset x29, 0
+	.cfi_rel_offset x30, 8
+	mov	x29, sp
+	.inst	0x04e0e3f0  /* cntd	x16  */
+	str	x16, [sp, 16]
+	.cfi_rel_offset 46, 16
+	.inst	0xd503467f  /* smstop  */
+	bl	abort
+END (__arm_tpidr2_restore)
diff --git a/libgcc/config/aarch64/__arm_tpidr2_save.S b/libgcc/config/aarch64/__arm_tpidr2_save.S
new file mode 100644
index 00000000000..879cf798079
--- /dev/null
+++ b/libgcc/config/aarch64/__arm_tpidr2_save.S
@@ -0,0 +1,101 @@ 
+/* Support routine for SME.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "aarch64-asm.h"
+
+/* Used for lazy ZA save.  Call ABI:
+   - Private ZA, streaming-compatible.
+   - x0-x13, x19-x29, sp and fp regs are call preserved.
+   - Takes no argument.
+   - Does not return a value.
+   - Can abort on failure (then registers are not preserved).  */
+
+.hidden __aarch64_have_sme
+
+variant_pcs (__arm_tpidr2_save)
+
+ENTRY (__arm_tpidr2_save)
+	/* Check if SME is available.  */
+	adrp	x14, __aarch64_have_sme
+	ldrb	w14, [x14, :lo12:__aarch64_have_sme]
+	cbz	w14, L(end)
+
+	.inst	0xd53bd0ae  /* mrs	x14, tpidr2_el0  */
+	cbz	x14, L(end)
+
+	/* check reserved bytes.  */
+	ldrh	w15, [x14, 10]
+	ldr	w16, [x14, 12]
+	orr	w15, w15, w16
+	cbnz	w15, L(fail)
+
+	ldr	x16, [x14]
+	cbz	x16, L(end)
+	ldrh	w17, [x14, 8]
+	cbz	w17, L(end)
+
+	/* x14: tpidr2, x15: 0,
+	   x16: za_save_buffer, x17: num_za_save_slices.  */
+
+L(save_loop):
+	.inst	0xe1206200  /* str	za[w15, 0], [x16]  */
+	.inst	0xe1206201  /* str	za[w15, 1], [x16, 1, mul vl] */
+	.inst	0xe1206202  /* str	za[w15, 2], [x16, 2, mul vl] */
+	.inst	0xe1206203  /* str	za[w15, 3], [x16, 3, mul vl] */
+	.inst	0xe1206204  /* str	za[w15, 4], [x16, 4, mul vl] */
+	.inst	0xe1206205  /* str	za[w15, 5], [x16, 5, mul vl] */
+	.inst	0xe1206206  /* str	za[w15, 6], [x16, 6, mul vl] */
+	.inst	0xe1206207  /* str	za[w15, 7], [x16, 7, mul vl] */
+	.inst	0xe1206208  /* str	za[w15, 8], [x16, 8, mul vl] */
+	.inst	0xe1206209  /* str	za[w15, 9], [x16, 9, mul vl] */
+	.inst	0xe120620a  /* str	za[w15, 10], [x16, 10, mul vl] */
+	.inst	0xe120620b  /* str	za[w15, 11], [x16, 11, mul vl] */
+	.inst	0xe120620c  /* str	za[w15, 12], [x16, 12, mul vl] */
+	.inst	0xe120620d  /* str	za[w15, 13], [x16, 13, mul vl] */
+	.inst	0xe120620e  /* str	za[w15, 14], [x16, 14, mul vl] */
+	.inst	0xe120620f  /* str	za[w15, 15], [x16, 15, mul vl] */
+	add	w15, w15, 16
+	.inst	0x04305a10  /* addsvl	x16, x16, 16  */
+	cmp	w17, w15
+	bhi	L(save_loop)
+L(end):
+	ret
+L(fail):
+	PACIASP
+	stp	x29, x30, [sp, -32]!
+	.cfi_adjust_cfa_offset 32
+	.cfi_rel_offset x29, 0
+	.cfi_rel_offset x30, 8
+	mov	x29, sp
+	.inst	0x04e0e3f0  /* cntd	x16  */
+	str	x16, [sp, 16]
+	.cfi_rel_offset 46, 16
+	.inst	0xd503467f  /* smstop  */
+	bl	abort
+END (__arm_tpidr2_save)
+
+/* Hidden alias used by __arm_za_disable.  */
+.global __libgcc_arm_tpidr2_save
+.hidden __libgcc_arm_tpidr2_save
+.set __libgcc_arm_tpidr2_save, __arm_tpidr2_save
diff --git a/libgcc/config/aarch64/__arm_za_disable.S b/libgcc/config/aarch64/__arm_za_disable.S
new file mode 100644
index 00000000000..cff5b9cec47
--- /dev/null
+++ b/libgcc/config/aarch64/__arm_za_disable.S
@@ -0,0 +1,65 @@ 
+/* Support routine for SME.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "aarch64-asm.h"
+
+/* Disable ZA.  Call ABI:
+   - Private ZA, streaming-compatible.
+   - x0-x13, x19-x29, sp and fp regs are call preserved.
+   - Takes no argument.
+   - Does not return a value.
+   - Can abort on failure (then registers are not preserved).  */
+
+.hidden __aarch64_have_sme
+
+.hidden __libgcc_arm_tpidr2_save
+
+variant_pcs (__arm_za_disable)
+
+ENTRY (__arm_za_disable)
+	/* Check if SME is available.  */
+	adrp	x14, __aarch64_have_sme
+	ldrb	w14, [x14, :lo12:__aarch64_have_sme]
+	cbz	w14, L(end)
+
+	.inst	0xd53bd0ae  /* mrs	x14, tpidr2_el0  */
+	cbz	x14, L(end)
+
+	PACIASP
+	stp	x29, x30, [sp, -16]!
+	.cfi_adjust_cfa_offset 16
+	.cfi_rel_offset x29, 0
+	.cfi_rel_offset x30, 8
+	mov	x29, sp
+	bl	__libgcc_arm_tpidr2_save
+	.inst	0xd51bd0bf  /* msr	tpidr2_el0, xzr  */
+	.inst	0xd503447f  /* smstop	za  */
+	ldp	x29, x30, [sp], 16
+	.cfi_adjust_cfa_offset -16
+	.cfi_restore x29
+	.cfi_restore x30
+	AUTIASP
+L(end):
+	ret
+END (__arm_za_disable)
diff --git a/libgcc/config/aarch64/aarch64-asm.h b/libgcc/config/aarch64/aarch64-asm.h
new file mode 100644
index 00000000000..8969b06b09c
--- /dev/null
+++ b/libgcc/config/aarch64/aarch64-asm.h
@@ -0,0 +1,98 @@ 
+/* AArch64 asm definitions.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "auto-target.h"
+
+#define L(label) .L ## label
+
+/* Marking variant PCS symbol references is important for PLT calls
+   otherwise it is for documenting the PCS in the symbol table.  */
+#ifdef HAVE_AS_VARIANT_PCS
+# define variant_pcs(name) .variant_pcs name
+#else
+# define variant_pcs(name)
+#endif
+
+/* GNU_PROPERTY_AARCH64_* macros from elf.h for use in asm code.  */
+#define FEATURE_1_AND 0xc0000000
+#define FEATURE_1_BTI 1
+#define FEATURE_1_PAC 2
+
+/* Supported features based on the code generation options.  */
+#if defined(__ARM_FEATURE_BTI_DEFAULT)
+# define BTI_FLAG FEATURE_1_BTI
+# define BTI_C hint	34
+#else
+# define BTI_FLAG 0
+# define BTI_C
+#endif
+
+#if __ARM_FEATURE_PAC_DEFAULT & 3
+# define PAC_FLAG FEATURE_1_PAC
+# define PACIASP hint	25; .cfi_window_save
+# define AUTIASP hint	29; .cfi_window_save
+#else
+# define PAC_FLAG 0
+# define PACIASP
+# define AUTIASP
+#endif
+
+/* Add a NT_GNU_PROPERTY_TYPE_0 note.  */
+#define GNU_PROPERTY(type, value)	\
+  .section .note.gnu.property, "a";	\
+  .p2align 3;				\
+  .word 4;				\
+  .word 16;				\
+  .word 5;				\
+  .asciz "GNU";				\
+  .word type;				\
+  .word 4;				\
+  .word value;				\
+  .word 0;				\
+  .previous
+
+#if defined(__linux__) || defined(__FreeBSD__)
+/* Do not require executable stack.  */
+.section .note.GNU-stack, "", %progbits
+.previous
+
+/* Add GNU property note if built with branch protection.  */
+# if (BTI_FLAG|PAC_FLAG) != 0
+GNU_PROPERTY (FEATURE_1_AND, BTI_FLAG|PAC_FLAG)
+# endif
+#endif
+
+#define ENTRY_ALIGN(name, align) \
+  .global name;		\
+  .type name,%function;	\
+  .balign align;	\
+  name:			\
+  .cfi_startproc;	\
+  BTI_C
+
+#define ENTRY(name) ENTRY_ALIGN(name, 16)
+
+#define END(name) \
+  .cfi_endproc;		\
+  .size name, .-name
diff --git a/libgcc/config/aarch64/libgcc-sme.ver b/libgcc/config/aarch64/libgcc-sme.ver
new file mode 100644
index 00000000000..da889c6c09e
--- /dev/null
+++ b/libgcc/config/aarch64/libgcc-sme.ver
@@ -0,0 +1,24 @@ 
+# Copyright (C) 2023 Free Software Foundation, Inc.
+#
+# This file is part of GCC.
+#
+# GCC is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GCC 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GCC; see the file COPYING3.  If not see
+# <http://www.gnu.org/licenses/>.
+
+GCC_14.0 {
+  __arm_sme_state
+  __arm_tpidr2_restore
+  __arm_tpidr2_save
+  __arm_za_disable
+}
diff --git a/libgcc/config/aarch64/t-aarch64 b/libgcc/config/aarch64/t-aarch64
index a40b6241c86..7b852022a4d 100644
--- a/libgcc/config/aarch64/t-aarch64
+++ b/libgcc/config/aarch64/t-aarch64
@@ -19,3 +19,13 @@ 
 # <http://www.gnu.org/licenses/>.
 
 LIB2ADD += $(srcdir)/config/aarch64/sync-cache.c
+
+# Add sme runtime to shared libgcc
+LIB2ADDEH += \
+	$(srcdir)/config/aarch64/__aarch64_have_sme.c \
+	$(srcdir)/config/aarch64/__arm_sme_state.S \
+	$(srcdir)/config/aarch64/__arm_tpidr2_restore.S \
+	$(srcdir)/config/aarch64/__arm_tpidr2_save.S \
+	$(srcdir)/config/aarch64/__arm_za_disable.S
+
+SHLIB_MAPFILES += $(srcdir)/config/aarch64/libgcc-sme.ver