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authorWilco Dijkstra <wdijkstr@arm.com>2022-10-26 14:16:50 +0100
committerWilco Dijkstra <wilco.dijkstra@arm.com>2024-04-11 13:47:20 +0100
commitf3095d3eb6d80b1f07f3410284e3880c7b3d9562 (patch)
tree2f5c5347b434e48ddfb7dea1049ffbf28de60a00
parent47f69077d5d4fe0eb6939a57e5f49b90a856c860 (diff)
downloadglibc-release/2.28/master.tar.gz
glibc-release/2.28/master.tar.xz
glibc-release/2.28/master.zip
aarch64: Use memcpy_simd as the default memcpy release/2.28/master
Since __memcpy_simd is the fastest memcpy on almost all cores, replace
the generic memcpy with it.

(cherry picked from commit 531717afbc49c5cf1d994ddf827891abc906056a)
-rw-r--r--sysdeps/aarch64/memcpy.S187
-rw-r--r--sysdeps/aarch64/multiarch/Makefile2
-rw-r--r--sysdeps/aarch64/multiarch/ifunc-impl-list.c2
-rw-r--r--sysdeps/aarch64/multiarch/memcpy.c6
-rw-r--r--sysdeps/aarch64/multiarch/memcpy_advsimd.S248
-rw-r--r--sysdeps/aarch64/multiarch/memmove.c6
6 files changed, 81 insertions, 370 deletions
diff --git a/sysdeps/aarch64/memcpy.S b/sysdeps/aarch64/memcpy.S
index 919b28d7e1..36353cab21 100644
--- a/sysdeps/aarch64/memcpy.S
+++ b/sysdeps/aarch64/memcpy.S
@@ -1,4 +1,5 @@
-/* Copyright (C) 2012-2018 Free Software Foundation, Inc.
+/* Generic optimized memcpy using SIMD.
+   Copyright (C) 2012-2022 Free Software Foundation, Inc.
 
    This file is part of the GNU C Library.
 
@@ -20,7 +21,7 @@
 
 /* Assumptions:
  *
- * ARMv8-a, AArch64, unaligned accesses.
+ * ARMv8-a, AArch64, Advanced SIMD, unaligned accesses.
  *
  */
 
@@ -36,21 +37,18 @@
 #define B_l	x8
 #define B_lw	w8
 #define B_h	x9
-#define C_l	x10
 #define C_lw	w10
-#define C_h	x11
-#define D_l	x12
-#define D_h	x13
-#define E_l	x14
-#define E_h	x15
-#define F_l	x16
-#define F_h	x17
-#define G_l	count
-#define G_h	dst
-#define H_l	src
-#define H_h	srcend
 #define tmp1	x14
 
+#define A_q	q0
+#define B_q	q1
+#define C_q	q2
+#define D_q	q3
+#define E_q	q4
+#define F_q	q5
+#define G_q	q6
+#define H_q	q7
+
 #ifndef MEMMOVE
 # define MEMMOVE memmove
 #endif
@@ -69,8 +67,7 @@
    Large copies use a software pipelined loop processing 64 bytes per
    iteration.  The destination pointer is 16-byte aligned to minimize
    unaligned accesses.  The loop tail is handled by always copying 64 bytes
-   from the end.
-*/
+   from the end.  */
 
 ENTRY_ALIGN (MEMCPY, 6)
 	DELOUSE (0)
@@ -87,10 +84,10 @@ ENTRY_ALIGN (MEMCPY, 6)
 	/* Small copies: 0..32 bytes.  */
 	cmp	count, 16
 	b.lo	L(copy16)
-	ldp	A_l, A_h, [src]
-	ldp	D_l, D_h, [srcend, -16]
-	stp	A_l, A_h, [dstin]
-	stp	D_l, D_h, [dstend, -16]
+	ldr	A_q, [src]
+	ldr	B_q, [srcend, -16]
+	str	A_q, [dstin]
+	str	B_q, [dstend, -16]
 	ret
 
 	/* Copy 8-15 bytes.  */
@@ -102,7 +99,6 @@ L(copy16):
 	str	A_h, [dstend, -8]
 	ret
 
-	.p2align 3
 	/* Copy 4-7 bytes.  */
 L(copy8):
 	tbz	count, 2, L(copy4)
@@ -128,81 +124,62 @@ L(copy0):
 	.p2align 4
 	/* Medium copies: 33..128 bytes.  */
 L(copy32_128):
-	ldp	A_l, A_h, [src]
-	ldp	B_l, B_h, [src, 16]
-	ldp	C_l, C_h, [srcend, -32]
-	ldp	D_l, D_h, [srcend, -16]
+	ldp	A_q, B_q, [src]
+	ldp	C_q, D_q, [srcend, -32]
 	cmp	count, 64
 	b.hi	L(copy128)
-	stp	A_l, A_h, [dstin]
-	stp	B_l, B_h, [dstin, 16]
-	stp	C_l, C_h, [dstend, -32]
-	stp	D_l, D_h, [dstend, -16]
+	stp	A_q, B_q, [dstin]
+	stp	C_q, D_q, [dstend, -32]
 	ret
 
 	.p2align 4
 	/* Copy 65..128 bytes.  */
 L(copy128):
-	ldp	E_l, E_h, [src, 32]
-	ldp	F_l, F_h, [src, 48]
+	ldp	E_q, F_q, [src, 32]
 	cmp	count, 96
 	b.ls	L(copy96)
-	ldp	G_l, G_h, [srcend, -64]
-	ldp	H_l, H_h, [srcend, -48]
-	stp	G_l, G_h, [dstend, -64]
-	stp	H_l, H_h, [dstend, -48]
+	ldp	G_q, H_q, [srcend, -64]
+	stp	G_q, H_q, [dstend, -64]
 L(copy96):
-	stp	A_l, A_h, [dstin]
-	stp	B_l, B_h, [dstin, 16]
-	stp	E_l, E_h, [dstin, 32]
-	stp	F_l, F_h, [dstin, 48]
-	stp	C_l, C_h, [dstend, -32]
-	stp	D_l, D_h, [dstend, -16]
+	stp	A_q, B_q, [dstin]
+	stp	E_q, F_q, [dstin, 32]
+	stp	C_q, D_q, [dstend, -32]
 	ret
 
-	.p2align 4
+	/* Align loop64 below to 16 bytes.  */
+	nop
+
 	/* Copy more than 128 bytes.  */
 L(copy_long):
-	/* Copy 16 bytes and then align dst to 16-byte alignment.  */
-	ldp	D_l, D_h, [src]
-	and	tmp1, dstin, 15
-	bic	dst, dstin, 15
-	sub	src, src, tmp1
+	/* Copy 16 bytes and then align src to 16-byte alignment.  */
+	ldr	D_q, [src]
+	and	tmp1, src, 15
+	bic	src, src, 15
+	sub	dst, dstin, tmp1
 	add	count, count, tmp1	/* Count is now 16 too large.  */
-	ldp	A_l, A_h, [src, 16]
-	stp	D_l, D_h, [dstin]
-	ldp	B_l, B_h, [src, 32]
-	ldp	C_l, C_h, [src, 48]
-	ldp	D_l, D_h, [src, 64]!
+	ldp	A_q, B_q, [src, 16]
+	str	D_q, [dstin]
+	ldp	C_q, D_q, [src, 48]
 	subs	count, count, 128 + 16	/* Test and readjust count.  */
 	b.ls	L(copy64_from_end)
-
 L(loop64):
-	stp	A_l, A_h, [dst, 16]
-	ldp	A_l, A_h, [src, 16]
-	stp	B_l, B_h, [dst, 32]
-	ldp	B_l, B_h, [src, 32]
-	stp	C_l, C_h, [dst, 48]
-	ldp	C_l, C_h, [src, 48]
-	stp	D_l, D_h, [dst, 64]!
-	ldp	D_l, D_h, [src, 64]!
+	stp	A_q, B_q, [dst, 16]
+	ldp	A_q, B_q, [src, 80]
+	stp	C_q, D_q, [dst, 48]
+	ldp	C_q, D_q, [src, 112]
+	add	src, src, 64
+	add	dst, dst, 64
 	subs	count, count, 64
 	b.hi	L(loop64)
 
 	/* Write the last iteration and copy 64 bytes from the end.  */
 L(copy64_from_end):
-	ldp	E_l, E_h, [srcend, -64]
-	stp	A_l, A_h, [dst, 16]
-	ldp	A_l, A_h, [srcend, -48]
-	stp	B_l, B_h, [dst, 32]
-	ldp	B_l, B_h, [srcend, -32]
-	stp	C_l, C_h, [dst, 48]
-	ldp	C_l, C_h, [srcend, -16]
-	stp	D_l, D_h, [dst, 64]
-	stp	E_l, E_h, [dstend, -64]
-	stp	A_l, A_h, [dstend, -48]
-	stp	B_l, B_h, [dstend, -32]
-	stp	C_l, C_h, [dstend, -16]
+	ldp	E_q, F_q, [srcend, -64]
+	stp	A_q, B_q, [dst, 16]
+	ldp	A_q, B_q, [srcend, -32]
+	stp	C_q, D_q, [dst, 48]
+	stp	E_q, F_q, [dstend, -64]
+	stp	A_q, B_q, [dstend, -32]
 	ret
 
 END (MEMCPY)
@@ -220,64 +197,56 @@ ENTRY_ALIGN (MEMMOVE, 4)
 	cmp	count, 32
 	b.hi	L(copy32_128)
 
-	/* Small copies: 0..32 bytes.  */
+	/* Small moves: 0..32 bytes.  */
 	cmp	count, 16
 	b.lo	L(copy16)
-	ldp	A_l, A_h, [src]
-	ldp	D_l, D_h, [srcend, -16]
-	stp	A_l, A_h, [dstin]
-	stp	D_l, D_h, [dstend, -16]
+	ldr	A_q, [src]
+	ldr	B_q, [srcend, -16]
+	str	A_q, [dstin]
+	str	B_q, [dstend, -16]
 	ret
 
-	.p2align 4
 L(move_long):
 	/* Only use backward copy if there is an overlap.  */
 	sub	tmp1, dstin, src
-	cbz	tmp1, L(copy0)
+	cbz	tmp1, L(move0)
 	cmp	tmp1, count
 	b.hs	L(copy_long)
 
 	/* Large backwards copy for overlapping copies.
-	   Copy 16 bytes and then align dst to 16-byte alignment.  */
-	ldp	D_l, D_h, [srcend, -16]
-	and	tmp1, dstend, 15
-	sub	srcend, srcend, tmp1
+	   Copy 16 bytes and then align srcend to 16-byte alignment.  */
+L(copy_long_backwards):
+	ldr	D_q, [srcend, -16]
+	and	tmp1, srcend, 15
+	bic	srcend, srcend, 15
 	sub	count, count, tmp1
-	ldp	A_l, A_h, [srcend, -16]
-	stp	D_l, D_h, [dstend, -16]
-	ldp	B_l, B_h, [srcend, -32]
-	ldp	C_l, C_h, [srcend, -48]
-	ldp	D_l, D_h, [srcend, -64]!
+	ldp	A_q, B_q, [srcend, -32]
+	str	D_q, [dstend, -16]
+	ldp	C_q, D_q, [srcend, -64]
 	sub	dstend, dstend, tmp1
 	subs	count, count, 128
 	b.ls	L(copy64_from_start)
 
 L(loop64_backwards):
-	stp	A_l, A_h, [dstend, -16]
-	ldp	A_l, A_h, [srcend, -16]
-	stp	B_l, B_h, [dstend, -32]
-	ldp	B_l, B_h, [srcend, -32]
-	stp	C_l, C_h, [dstend, -48]
-	ldp	C_l, C_h, [srcend, -48]
-	stp	D_l, D_h, [dstend, -64]!
-	ldp	D_l, D_h, [srcend, -64]!
+	str	B_q, [dstend, -16]
+	str	A_q, [dstend, -32]
+	ldp	A_q, B_q, [srcend, -96]
+	str	D_q, [dstend, -48]
+	str	C_q, [dstend, -64]!
+	ldp	C_q, D_q, [srcend, -128]
+	sub	srcend, srcend, 64
 	subs	count, count, 64
 	b.hi	L(loop64_backwards)
 
 	/* Write the last iteration and copy 64 bytes from the start.  */
 L(copy64_from_start):
-	ldp	G_l, G_h, [src, 48]
-	stp	A_l, A_h, [dstend, -16]
-	ldp	A_l, A_h, [src, 32]
-	stp	B_l, B_h, [dstend, -32]
-	ldp	B_l, B_h, [src, 16]
-	stp	C_l, C_h, [dstend, -48]
-	ldp	C_l, C_h, [src]
-	stp	D_l, D_h, [dstend, -64]
-	stp	G_l, G_h, [dstin, 48]
-	stp	A_l, A_h, [dstin, 32]
-	stp	B_l, B_h, [dstin, 16]
-	stp	C_l, C_h, [dstin]
+	ldp	E_q, F_q, [src, 32]
+	stp	A_q, B_q, [dstend, -32]
+	ldp	A_q, B_q, [src]
+	stp	C_q, D_q, [dstend, -64]
+	stp	E_q, F_q, [dstin, 32]
+	stp	A_q, B_q, [dstin]
+L(move0):
 	ret
 
 END (MEMMOVE)
diff --git a/sysdeps/aarch64/multiarch/Makefile b/sysdeps/aarch64/multiarch/Makefile
index 134fe463fd..57ffdf7238 100644
--- a/sysdeps/aarch64/multiarch/Makefile
+++ b/sysdeps/aarch64/multiarch/Makefile
@@ -1,4 +1,4 @@
 ifeq ($(subdir),string)
-sysdep_routines += memcpy_generic memcpy_advsimd memcpy_thunderx memcpy_thunderx2 \
+sysdep_routines += memcpy_generic memcpy_thunderx memcpy_thunderx2 \
 		   memcpy_falkor memmove_falkor memset_generic memset_falkor
 endif
diff --git a/sysdeps/aarch64/multiarch/ifunc-impl-list.c b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
index 0ccd14118c..e55be80103 100644
--- a/sysdeps/aarch64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
@@ -42,12 +42,10 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 	      IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_thunderx)
 	      IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_thunderx2)
 	      IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_falkor)
-	      IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_simd)
 	      IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_generic))
   IFUNC_IMPL (i, name, memmove,
 	      IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_thunderx)
 	      IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_falkor)
-	      IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_simd)
 	      IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_generic))
   IFUNC_IMPL (i, name, memset,
 	      /* Enable this on non-falkor processors too so that other cores
diff --git a/sysdeps/aarch64/multiarch/memcpy.c b/sysdeps/aarch64/multiarch/memcpy.c
index e69a1ae5af..4a04a63b0f 100644
--- a/sysdeps/aarch64/multiarch/memcpy.c
+++ b/sysdeps/aarch64/multiarch/memcpy.c
@@ -29,7 +29,6 @@
 extern __typeof (__redirect_memcpy) __libc_memcpy;
 
 extern __typeof (__redirect_memcpy) __memcpy_generic attribute_hidden;
-extern __typeof (__redirect_memcpy) __memcpy_simd attribute_hidden;
 extern __typeof (__redirect_memcpy) __memcpy_thunderx attribute_hidden;
 extern __typeof (__redirect_memcpy) __memcpy_thunderx2 attribute_hidden;
 extern __typeof (__redirect_memcpy) __memcpy_falkor attribute_hidden;
@@ -41,10 +40,7 @@ libc_ifunc (__libc_memcpy,
 		? __memcpy_falkor
 		: (IS_THUNDERX2 (midr) || IS_THUNDERX2PA (midr)
 		  ? __memcpy_thunderx2
-		  : (IS_NEOVERSE_N1 (midr) || IS_NEOVERSE_N2 (midr)
-		     || IS_NEOVERSE_V1 (midr)
-		     ? __memcpy_simd
-		     : __memcpy_generic)))));
+		  : __memcpy_generic))));
 
 # undef memcpy
 strong_alias (__libc_memcpy, memcpy);
diff --git a/sysdeps/aarch64/multiarch/memcpy_advsimd.S b/sysdeps/aarch64/multiarch/memcpy_advsimd.S
deleted file mode 100644
index 48bb6d7ca4..0000000000
--- a/sysdeps/aarch64/multiarch/memcpy_advsimd.S
+++ /dev/null
@@ -1,248 +0,0 @@
-/* Generic optimized memcpy using SIMD.
-   Copyright (C) 2020 Free Software Foundation, Inc.
-
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library.  If not, see
-   <https://www.gnu.org/licenses/>.  */
-
-#include <sysdep.h>
-
-/* Assumptions:
- *
- * ARMv8-a, AArch64, Advanced SIMD, unaligned accesses.
- *
- */
-
-#define dstin	x0
-#define src	x1
-#define count	x2
-#define dst	x3
-#define srcend	x4
-#define dstend	x5
-#define A_l	x6
-#define A_lw	w6
-#define A_h	x7
-#define B_l	x8
-#define B_lw	w8
-#define B_h	x9
-#define C_lw	w10
-#define tmp1	x14
-
-#define A_q	q0
-#define B_q	q1
-#define C_q	q2
-#define D_q	q3
-#define E_q	q4
-#define F_q	q5
-#define G_q	q6
-#define H_q	q7
-
-
-/* This implementation supports both memcpy and memmove and shares most code.
-   It uses unaligned accesses and branchless sequences to keep the code small,
-   simple and improve performance.
-
-   Copies are split into 3 main cases: small copies of up to 32 bytes, medium
-   copies of up to 128 bytes, and large copies.  The overhead of the overlap
-   check in memmove is negligible since it is only required for large copies.
-
-   Large copies use a software pipelined loop processing 64 bytes per
-   iteration.  The destination pointer is 16-byte aligned to minimize
-   unaligned accesses.  The loop tail is handled by always copying 64 bytes
-   from the end.  */
-
-ENTRY (__memcpy_simd)
-	DELOUSE (0)
-	DELOUSE (1)
-	DELOUSE (2)
-
-	add	srcend, src, count
-	add	dstend, dstin, count
-	cmp	count, 128
-	b.hi	L(copy_long)
-	cmp	count, 32
-	b.hi	L(copy32_128)
-
-	/* Small copies: 0..32 bytes.  */
-	cmp	count, 16
-	b.lo	L(copy16)
-	ldr	A_q, [src]
-	ldr	B_q, [srcend, -16]
-	str	A_q, [dstin]
-	str	B_q, [dstend, -16]
-	ret
-
-	/* Copy 8-15 bytes.  */
-L(copy16):
-	tbz	count, 3, L(copy8)
-	ldr	A_l, [src]
-	ldr	A_h, [srcend, -8]
-	str	A_l, [dstin]
-	str	A_h, [dstend, -8]
-	ret
-
-	/* Copy 4-7 bytes.  */
-L(copy8):
-	tbz	count, 2, L(copy4)
-	ldr	A_lw, [src]
-	ldr	B_lw, [srcend, -4]
-	str	A_lw, [dstin]
-	str	B_lw, [dstend, -4]
-	ret
-
-	/* Copy 0..3 bytes using a branchless sequence.  */
-L(copy4):
-	cbz	count, L(copy0)
-	lsr	tmp1, count, 1
-	ldrb	A_lw, [src]
-	ldrb	C_lw, [srcend, -1]
-	ldrb	B_lw, [src, tmp1]
-	strb	A_lw, [dstin]
-	strb	B_lw, [dstin, tmp1]
-	strb	C_lw, [dstend, -1]
-L(copy0):
-	ret
-
-	.p2align 4
-	/* Medium copies: 33..128 bytes.  */
-L(copy32_128):
-	ldp	A_q, B_q, [src]
-	ldp	C_q, D_q, [srcend, -32]
-	cmp	count, 64
-	b.hi	L(copy128)
-	stp	A_q, B_q, [dstin]
-	stp	C_q, D_q, [dstend, -32]
-	ret
-
-	.p2align 4
-	/* Copy 65..128 bytes.  */
-L(copy128):
-	ldp	E_q, F_q, [src, 32]
-	cmp	count, 96
-	b.ls	L(copy96)
-	ldp	G_q, H_q, [srcend, -64]
-	stp	G_q, H_q, [dstend, -64]
-L(copy96):
-	stp	A_q, B_q, [dstin]
-	stp	E_q, F_q, [dstin, 32]
-	stp	C_q, D_q, [dstend, -32]
-	ret
-
-	/* Align loop64 below to 16 bytes.  */
-	nop
-
-	/* Copy more than 128 bytes.  */
-L(copy_long):
-	/* Copy 16 bytes and then align src to 16-byte alignment.  */
-	ldr	D_q, [src]
-	and	tmp1, src, 15
-	bic	src, src, 15
-	sub	dst, dstin, tmp1
-	add	count, count, tmp1	/* Count is now 16 too large.  */
-	ldp	A_q, B_q, [src, 16]
-	str	D_q, [dstin]
-	ldp	C_q, D_q, [src, 48]
-	subs	count, count, 128 + 16	/* Test and readjust count.  */
-	b.ls	L(copy64_from_end)
-L(loop64):
-	stp	A_q, B_q, [dst, 16]
-	ldp	A_q, B_q, [src, 80]
-	stp	C_q, D_q, [dst, 48]
-	ldp	C_q, D_q, [src, 112]
-	add	src, src, 64
-	add	dst, dst, 64
-	subs	count, count, 64
-	b.hi	L(loop64)
-
-	/* Write the last iteration and copy 64 bytes from the end.  */
-L(copy64_from_end):
-	ldp	E_q, F_q, [srcend, -64]
-	stp	A_q, B_q, [dst, 16]
-	ldp	A_q, B_q, [srcend, -32]
-	stp	C_q, D_q, [dst, 48]
-	stp	E_q, F_q, [dstend, -64]
-	stp	A_q, B_q, [dstend, -32]
-	ret
-
-END (__memcpy_simd)
-libc_hidden_builtin_def (__memcpy_simd)
-
-
-ENTRY (__memmove_simd)
-	DELOUSE (0)
-	DELOUSE (1)
-	DELOUSE (2)
-
-	add	srcend, src, count
-	add	dstend, dstin, count
-	cmp	count, 128
-	b.hi	L(move_long)
-	cmp	count, 32
-	b.hi	L(copy32_128)
-
-	/* Small moves: 0..32 bytes.  */
-	cmp	count, 16
-	b.lo	L(copy16)
-	ldr	A_q, [src]
-	ldr	B_q, [srcend, -16]
-	str	A_q, [dstin]
-	str	B_q, [dstend, -16]
-	ret
-
-L(move_long):
-	/* Only use backward copy if there is an overlap.  */
-	sub	tmp1, dstin, src
-	cbz	tmp1, L(move0)
-	cmp	tmp1, count
-	b.hs	L(copy_long)
-
-	/* Large backwards copy for overlapping copies.
-	   Copy 16 bytes and then align srcend to 16-byte alignment.  */
-L(copy_long_backwards):
-	ldr	D_q, [srcend, -16]
-	and	tmp1, srcend, 15
-	bic	srcend, srcend, 15
-	sub	count, count, tmp1
-	ldp	A_q, B_q, [srcend, -32]
-	str	D_q, [dstend, -16]
-	ldp	C_q, D_q, [srcend, -64]
-	sub	dstend, dstend, tmp1
-	subs	count, count, 128
-	b.ls	L(copy64_from_start)
-
-L(loop64_backwards):
-	str	B_q, [dstend, -16]
-	str	A_q, [dstend, -32]
-	ldp	A_q, B_q, [srcend, -96]
-	str	D_q, [dstend, -48]
-	str	C_q, [dstend, -64]!
-	ldp	C_q, D_q, [srcend, -128]
-	sub	srcend, srcend, 64
-	subs	count, count, 64
-	b.hi	L(loop64_backwards)
-
-	/* Write the last iteration and copy 64 bytes from the start.  */
-L(copy64_from_start):
-	ldp	E_q, F_q, [src, 32]
-	stp	A_q, B_q, [dstend, -32]
-	ldp	A_q, B_q, [src]
-	stp	C_q, D_q, [dstend, -64]
-	stp	E_q, F_q, [dstin, 32]
-	stp	A_q, B_q, [dstin]
-L(move0):
-	ret
-
-END (__memmove_simd)
-libc_hidden_builtin_def (__memmove_simd)
diff --git a/sysdeps/aarch64/multiarch/memmove.c b/sysdeps/aarch64/multiarch/memmove.c
index b426dad834..e69d816291 100644
--- a/sysdeps/aarch64/multiarch/memmove.c
+++ b/sysdeps/aarch64/multiarch/memmove.c
@@ -29,7 +29,6 @@
 extern __typeof (__redirect_memmove) __libc_memmove;
 
 extern __typeof (__redirect_memmove) __memmove_generic attribute_hidden;
-extern __typeof (__redirect_memmove) __memmove_simd attribute_hidden;
 extern __typeof (__redirect_memmove) __memmove_thunderx attribute_hidden;
 extern __typeof (__redirect_memmove) __memmove_falkor attribute_hidden;
 
@@ -38,10 +37,7 @@ libc_ifunc (__libc_memmove,
 	     ? __memmove_thunderx
 	     : (IS_FALKOR (midr) || IS_PHECDA (midr)
 		? __memmove_falkor
-		  : (IS_NEOVERSE_N1 (midr) || IS_NEOVERSE_N2 (midr)
-		     || IS_NEOVERSE_V1 (midr)
-		     ? __memmove_simd
-		     : __memmove_generic))));
+		: __memmove_generic)));
 
 # undef memmove
 strong_alias (__libc_memmove, memmove);