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authorSteve Ellcey <sellcey@caviumnetworks.com>2017-05-24 23:46:48 (GMT)
committerSteve Ellcey <sellcey@caviumnetworks.com>2017-05-24 23:46:48 (GMT)
commit6a2c695266fab34cc057256d1b33d2268183f00e (patch)
tree320796a70561a5459b120bc2f99b4398dcc4970f
parent6edbe546d6ac243a5e3c2610853f2da53f0507b4 (diff)
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aarch64: Thunderx specific memcpy and memmove
* sysdeps/aarch64/memcpy.S (MEMMOVE, MEMCPY): New macros. (memmove): Use MEMMOVE for name. (memcpy): Use MEMCPY for name. Change internal labels to external labels. * sysdeps/aarch64/multiarch/Makefile: New file. * sysdeps/aarch64/multiarch/ifunc-impl-list.c: Likewise. * sysdeps/aarch64/multiarch/init-arch.h: Likewise. * sysdeps/aarch64/multiarch/memcpy.c: Likewise. * sysdeps/aarch64/multiarch/memcpy_generic.S: Likewise. * sysdeps/aarch64/multiarch/memcpy_thunderx.S: Likewise. * sysdeps/aarch64/multiarch/memmove.c: Likewise.
-rw-r--r--ChangeLog14
-rw-r--r--sysdeps/aarch64/memcpy.S27
-rw-r--r--sysdeps/aarch64/multiarch/Makefile3
-rw-r--r--sysdeps/aarch64/multiarch/ifunc-impl-list.c51
-rw-r--r--sysdeps/aarch64/multiarch/init-arch.h23
-rw-r--r--sysdeps/aarch64/multiarch/memcpy.c39
-rw-r--r--sysdeps/aarch64/multiarch/memcpy_generic.S42
-rw-r--r--sysdeps/aarch64/multiarch/memcpy_thunderx.S326
-rw-r--r--sysdeps/aarch64/multiarch/memmove.c39
9 files changed, 554 insertions, 10 deletions
diff --git a/ChangeLog b/ChangeLog
index d3f3d6a..bd66603 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2017-05-24 Steve Ellcey <sellcey@caviumnetworks.com>
+
+ * sysdeps/aarch64/memcpy.S (MEMMOVE, MEMCPY): New macros.
+ (memmove): Use MEMMOVE for name.
+ (memcpy): Use MEMCPY for name. Change internal labels
+ to external labels.
+ * sysdeps/aarch64/multiarch/Makefile: New file.
+ * sysdeps/aarch64/multiarch/ifunc-impl-list.c: Likewise.
+ * sysdeps/aarch64/multiarch/init-arch.h: Likewise.
+ * sysdeps/aarch64/multiarch/memcpy.c: Likewise.
+ * sysdeps/aarch64/multiarch/memcpy_generic.S: Likewise.
+ * sysdeps/aarch64/multiarch/memcpy_thunderx.S: Likewise.
+ * sysdeps/aarch64/multiarch/memmove.c: Likewise.
+
2017-05-24 Siddhesh Poyarekar <siddhesh@sourceware.org>
* sysdeps/unix/sysv/linux/arm/dl-procinfo.c
diff --git a/sysdeps/aarch64/memcpy.S b/sysdeps/aarch64/memcpy.S
index 29af8b1..88a3b90 100644
--- a/sysdeps/aarch64/memcpy.S
+++ b/sysdeps/aarch64/memcpy.S
@@ -59,7 +59,14 @@
Overlapping large forward memmoves use a loop that copies backwards.
*/
-ENTRY_ALIGN (memmove, 6)
+#ifndef MEMMOVE
+# define MEMMOVE memmove
+#endif
+#ifndef MEMCPY
+# define MEMCPY memcpy
+#endif
+
+ENTRY_ALIGN (MEMMOVE, 6)
DELOUSE (0)
DELOUSE (1)
@@ -71,9 +78,9 @@ ENTRY_ALIGN (memmove, 6)
b.lo L(move_long)
/* Common case falls through into memcpy. */
-END (memmove)
-libc_hidden_builtin_def (memmove)
-ENTRY (memcpy)
+END (MEMMOVE)
+libc_hidden_builtin_def (MEMMOVE)
+ENTRY (MEMCPY)
DELOUSE (0)
DELOUSE (1)
@@ -169,8 +176,8 @@ L(copy_long):
ldp C_l, C_h, [src, 48]
ldp D_l, D_h, [src, 64]!
subs count, count, 128 + 16 /* Test and readjust count. */
- b.ls 2f
-1:
+ b.ls L(last64)
+L(loop64):
stp A_l, A_h, [dst, 16]
ldp A_l, A_h, [src, 16]
stp B_l, B_h, [dst, 32]
@@ -180,12 +187,12 @@ L(copy_long):
stp D_l, D_h, [dst, 64]!
ldp D_l, D_h, [src, 64]!
subs count, count, 64
- b.hi 1b
+ b.hi L(loop64)
/* Write the last full set of 64 bytes. The remainder is at most 64
bytes, so it is safe to always copy 64 bytes from the end even if
there is just 1 byte left. */
-2:
+L(last64):
ldp E_l, E_h, [srcend, -64]
stp A_l, A_h, [dst, 16]
ldp A_l, A_h, [srcend, -48]
@@ -256,5 +263,5 @@ L(move_long):
stp C_l, C_h, [dstin]
3: ret
-END (memcpy)
-libc_hidden_builtin_def (memcpy)
+END (MEMCPY)
+libc_hidden_builtin_def (MEMCPY)
diff --git a/sysdeps/aarch64/multiarch/Makefile b/sysdeps/aarch64/multiarch/Makefile
new file mode 100644
index 0000000..78d52c7
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/Makefile
@@ -0,0 +1,3 @@
+ifeq ($(subdir),string)
+sysdep_routines += memcpy_generic memcpy_thunderx
+endif
diff --git a/sysdeps/aarch64/multiarch/ifunc-impl-list.c b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
new file mode 100644
index 0000000..c4f23df
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
@@ -0,0 +1,51 @@
+/* Enumerate available IFUNC implementations of a function. AARCH64 version.
+ Copyright (C) 2017 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 <assert.h>
+#include <string.h>
+#include <wchar.h>
+#include <ldsodefs.h>
+#include <ifunc-impl-list.h>
+#include <init-arch.h>
+#include <stdio.h>
+
+/* Maximum number of IFUNC implementations. */
+#define MAX_IFUNC 2
+
+size_t
+__libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
+ size_t max)
+{
+ assert (max >= MAX_IFUNC);
+
+ size_t i = 0;
+
+ INIT_ARCH ();
+
+ /* Support sysdeps/aarch64/multiarch/memcpy.c and memmove.c. */
+ IFUNC_IMPL (i, name, memcpy,
+ IFUNC_IMPL_ADD (array, i, memcpy, IS_THUNDERX (midr),
+ __memcpy_thunderx)
+ IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_generic))
+ IFUNC_IMPL (i, name, memmove,
+ IFUNC_IMPL_ADD (array, i, memmove, IS_THUNDERX (midr),
+ __memmove_thunderx)
+ IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_generic))
+
+ return i;
+}
diff --git a/sysdeps/aarch64/multiarch/init-arch.h b/sysdeps/aarch64/multiarch/init-arch.h
new file mode 100644
index 0000000..3af442c
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/init-arch.h
@@ -0,0 +1,23 @@
+/* Define INIT_ARCH so that midr is initialized before use by IFUNCs.
+ This file is part of the GNU C Library.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+
+ 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 <ldsodefs.h>
+
+#define INIT_ARCH() \
+ uint64_t __attribute__((unused)) midr = \
+ GLRO(dl_aarch64_cpu_features).midr_el1;
diff --git a/sysdeps/aarch64/multiarch/memcpy.c b/sysdeps/aarch64/multiarch/memcpy.c
new file mode 100644
index 0000000..9f73efb
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memcpy.c
@@ -0,0 +1,39 @@
+/* Multiple versions of memcpy. AARCH64 version.
+ Copyright (C) 2017 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/>. */
+
+/* Define multiple versions only for the definition in libc. */
+
+#if IS_IN (libc)
+/* Redefine memcpy so that the compiler won't complain about the type
+ mismatch with the IFUNC selector in strong_alias, below. */
+# undef memcpy
+# define memcpy __redirect_memcpy
+# include <string.h>
+# include <init-arch.h>
+
+extern __typeof (__redirect_memcpy) __libc_memcpy;
+
+extern __typeof (__redirect_memcpy) __memcpy_generic attribute_hidden;
+extern __typeof (__redirect_memcpy) __memcpy_thunderx attribute_hidden;
+
+libc_ifunc (__libc_memcpy,
+ IS_THUNDERX (midr) ? __memcpy_thunderx : __memcpy_generic);
+
+# undef memcpy
+strong_alias (__libc_memcpy, memcpy);
+#endif
diff --git a/sysdeps/aarch64/multiarch/memcpy_generic.S b/sysdeps/aarch64/multiarch/memcpy_generic.S
new file mode 100644
index 0000000..041a779
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memcpy_generic.S
@@ -0,0 +1,42 @@
+/* A Generic Optimized memcpy implementation for AARCH64.
+ Copyright (C) 2017 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/>. */
+
+/* The actual memcpy and memmove code is in ../memcpy.S. If we are
+ building libc this file defines __memcpy_generic and __memmove_generic.
+ Otherwise the include of ../memcpy.S will define the normal __memcpy
+ and__memmove entry points. */
+
+#include <sysdep.h>
+
+#if IS_IN (libc)
+
+# define MEMCPY __memcpy_generic
+# define MEMMOVE __memmove_generic
+
+/* Do not hide the generic versions of memcpy and memmove, we use them
+ internally. */
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(name)
+
+/* It doesn't make sense to send libc-internal memcpy calls through a PLT. */
+ .globl __GI_memcpy; __GI_memcpy = __memcpy_generic
+ .globl __GI_memmove; __GI_memmove = __memmove_generic
+
+#endif
+
+#include "../memcpy.S"
diff --git a/sysdeps/aarch64/multiarch/memcpy_thunderx.S b/sysdeps/aarch64/multiarch/memcpy_thunderx.S
new file mode 100644
index 0000000..5ac9e34
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memcpy_thunderx.S
@@ -0,0 +1,326 @@
+/* A Thunderx Optimized memcpy implementation for AARCH64.
+ Copyright (C) 2017 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/>. */
+
+/* The actual code in this memcpy and memmove should be identical to the
+ generic version except for the code under '#ifdef THUNDERX'. This is
+ to make is easier to keep this version and the generic version in sync
+ for changes that are not specific to thunderx. */
+
+#include <sysdep.h>
+
+/* Assumptions:
+ *
+ * ARMv8-a, AArch64, 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 A_hw w7
+#define B_l x8
+#define B_lw w8
+#define B_h x9
+#define C_l x10
+#define C_h x11
+#define D_l x12
+#define D_h x13
+#define E_l src
+#define E_h count
+#define F_l srcend
+#define F_h dst
+#define G_l count
+#define G_h dst
+#define tmp1 x14
+
+/* Copies are split into 3 main cases: small copies of up to 16 bytes,
+ medium copies of 17..96 bytes which are fully unrolled. Large copies
+ of more than 96 bytes align the destination and use an unrolled loop
+ processing 64 bytes per iteration.
+ In order to share code with memmove, small and medium copies read all
+ data before writing, allowing any kind of overlap. So small, medium
+ and large backwards memmoves are handled by falling through into memcpy.
+ Overlapping large forward memmoves use a loop that copies backwards.
+*/
+
+#ifndef MEMMOVE
+# define MEMMOVE memmove
+#endif
+#ifndef MEMCPY
+# define MEMCPY memcpy
+#endif
+
+#if IS_IN (libc)
+
+# undef MEMCPY
+# define MEMCPY __memcpy_thunderx
+# undef MEMMOVE
+# define MEMMOVE __memmove_thunderx
+# define USE_THUNDERX
+
+ENTRY_ALIGN (MEMMOVE, 6)
+
+ DELOUSE (0)
+ DELOUSE (1)
+ DELOUSE (2)
+
+ sub tmp1, dstin, src
+ cmp count, 96
+ ccmp tmp1, count, 2, hi
+ b.lo L(move_long)
+
+ /* Common case falls through into memcpy. */
+END (MEMMOVE)
+libc_hidden_builtin_def (MEMMOVE)
+ENTRY (MEMCPY)
+
+ DELOUSE (0)
+ DELOUSE (1)
+ DELOUSE (2)
+
+ prfm PLDL1KEEP, [src]
+ add srcend, src, count
+ add dstend, dstin, count
+ cmp count, 16
+ b.ls L(copy16)
+ cmp count, 96
+ b.hi L(copy_long)
+
+ /* Medium copies: 17..96 bytes. */
+ sub tmp1, count, 1
+ ldp A_l, A_h, [src]
+ tbnz tmp1, 6, L(copy96)
+ ldp D_l, D_h, [srcend, -16]
+ tbz tmp1, 5, 1f
+ ldp B_l, B_h, [src, 16]
+ ldp C_l, C_h, [srcend, -32]
+ stp B_l, B_h, [dstin, 16]
+ stp C_l, C_h, [dstend, -32]
+1:
+ stp A_l, A_h, [dstin]
+ stp D_l, D_h, [dstend, -16]
+ ret
+
+ .p2align 4
+ /* Small copies: 0..16 bytes. */
+L(copy16):
+ cmp count, 8
+ b.lo 1f
+ ldr A_l, [src]
+ ldr A_h, [srcend, -8]
+ str A_l, [dstin]
+ str A_h, [dstend, -8]
+ ret
+ .p2align 4
+1:
+ tbz count, 2, 1f
+ ldr A_lw, [src]
+ ldr A_hw, [srcend, -4]
+ str A_lw, [dstin]
+ str A_hw, [dstend, -4]
+ ret
+
+ /* Copy 0..3 bytes. Use a branchless sequence that copies the same
+ byte 3 times if count==1, or the 2nd byte twice if count==2. */
+1:
+ cbz count, 2f
+ lsr tmp1, count, 1
+ ldrb A_lw, [src]
+ ldrb A_hw, [srcend, -1]
+ ldrb B_lw, [src, tmp1]
+ strb A_lw, [dstin]
+ strb B_lw, [dstin, tmp1]
+ strb A_hw, [dstend, -1]
+2: ret
+
+ .p2align 4
+ /* Copy 64..96 bytes. Copy 64 bytes from the start and
+ 32 bytes from the end. */
+L(copy96):
+ ldp B_l, B_h, [src, 16]
+ ldp C_l, C_h, [src, 32]
+ ldp D_l, D_h, [src, 48]
+ ldp E_l, E_h, [srcend, -32]
+ ldp F_l, F_h, [srcend, -16]
+ stp A_l, A_h, [dstin]
+ stp B_l, B_h, [dstin, 16]
+ stp C_l, C_h, [dstin, 32]
+ stp D_l, D_h, [dstin, 48]
+ stp E_l, E_h, [dstend, -32]
+ stp F_l, F_h, [dstend, -16]
+ ret
+
+ /* Align DST to 16 byte alignment so that we don't cross cache line
+ boundaries on both loads and stores. There are at least 96 bytes
+ to copy, so copy 16 bytes unaligned and then align. The loop
+ copies 64 bytes per iteration and prefetches one iteration ahead. */
+
+ .p2align 4
+L(copy_long):
+
+# ifdef USE_THUNDERX
+
+ /* On thunderx, large memcpy's are helped by software prefetching.
+ This loop is identical to the one below it but with prefetching
+ instructions included. For loops that are less than 32768 bytes,
+ the prefetching does not help and slow the code down so we only
+ use the prefetching loop for the largest memcpys. */
+
+ cmp count, #32768
+ b.lo L(copy_long_without_prefetch)
+ and tmp1, dstin, 15
+ bic dst, dstin, 15
+ ldp D_l, D_h, [src]
+ sub src, src, tmp1
+ prfm pldl1strm, [src, 384]
+ 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]!
+ subs count, count, 128 + 16 /* Test and readjust count. */
+
+L(prefetch_loop64):
+ tbz src, #6, 1f
+ prfm pldl1strm, [src, 512]
+1:
+ 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]!
+ subs count, count, 64
+ b.hi L(prefetch_loop64)
+ b L(last64)
+
+L(copy_long_without_prefetch):
+# endif
+
+ and tmp1, dstin, 15
+ bic dst, dstin, 15
+ ldp D_l, D_h, [src]
+ sub src, src, 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]!
+ subs count, count, 128 + 16 /* Test and readjust count. */
+ b.ls L(last64)
+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]!
+ subs count, count, 64
+ b.hi L(loop64)
+
+ /* Write the last full set of 64 bytes. The remainder is at most 64
+ bytes, so it is safe to always copy 64 bytes from the end even if
+ there is just 1 byte left. */
+L(last64):
+ 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]
+ ret
+
+ .p2align 4
+L(move_long):
+ cbz tmp1, 3f
+
+ add srcend, src, count
+ add dstend, dstin, count
+
+ /* Align dstend to 16 byte alignment so that we don't cross cache line
+ boundaries on both loads and stores. There are at least 96 bytes
+ to copy, so copy 16 bytes unaligned and then align. The loop
+ copies 64 bytes per iteration and prefetches one iteration ahead. */
+
+ and tmp1, dstend, 15
+ ldp D_l, D_h, [srcend, -16]
+ sub srcend, srcend, tmp1
+ 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]!
+ sub dstend, dstend, tmp1
+ subs count, count, 128
+ b.ls 2f
+
+ nop
+1:
+ 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]!
+ subs count, count, 64
+ b.hi 1b
+
+ /* Write the last full set of 64 bytes. The remainder is at most 64
+ bytes, so it is safe to always copy 64 bytes from the start even if
+ there is just 1 byte left. */
+2:
+ 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]
+3: ret
+
+END (MEMCPY)
+libc_hidden_builtin_def (MEMCPY)
+
+#endif
diff --git a/sysdeps/aarch64/multiarch/memmove.c b/sysdeps/aarch64/multiarch/memmove.c
new file mode 100644
index 0000000..34c6b29
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memmove.c
@@ -0,0 +1,39 @@
+/* Multiple versions of memmove. AARCH64 version.
+ Copyright (C) 2017 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/>. */
+
+/* Define multiple versions only for the definition in libc. */
+
+#if IS_IN (libc)
+/* Redefine memmove so that the compiler won't complain about the type
+ mismatch with the IFUNC selector in strong_alias, below. */
+# undef memmove
+# define memmove __redirect_memmove
+# include <string.h>
+# include <init-arch.h>
+
+extern __typeof (__redirect_memmove) __libc_memmove;
+
+extern __typeof (__redirect_memmove) __memmove_generic attribute_hidden;
+extern __typeof (__redirect_memmove) __memmove_thunderx attribute_hidden;
+
+libc_ifunc (__libc_memmove,
+ IS_THUNDERX (midr) ? __memmove_thunderx : __memmove_generic);
+
+# undef memmove
+strong_alias (__libc_memmove, memmove);
+#endif