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-rw-r--r--sysdeps/aarch64/multiarch/Makefile3
-rw-r--r--sysdeps/aarch64/multiarch/ifunc-impl-list.c1
-rw-r--r--sysdeps/aarch64/multiarch/memmove.c7
-rw-r--r--sysdeps/aarch64/multiarch/memmove_falkor.S232
4 files changed, 241 insertions, 2 deletions
diff --git a/sysdeps/aarch64/multiarch/Makefile b/sysdeps/aarch64/multiarch/Makefile
index 164ba1ae4b..9aa1e79a80 100644
--- a/sysdeps/aarch64/multiarch/Makefile
+++ b/sysdeps/aarch64/multiarch/Makefile
@@ -1,3 +1,4 @@
 ifeq ($(subdir),string)
-sysdep_routines += memcpy_generic memcpy_thunderx memcpy_falkor
+sysdep_routines += memcpy_generic memcpy_thunderx memcpy_falkor \
+		   memmove_falkor
 endif
diff --git a/sysdeps/aarch64/multiarch/ifunc-impl-list.c b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
index 8e873b3d9f..2cb74d5b43 100644
--- a/sysdeps/aarch64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
@@ -44,6 +44,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 	      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_generic))
 
   return i;
diff --git a/sysdeps/aarch64/multiarch/memmove.c b/sysdeps/aarch64/multiarch/memmove.c
index 34c6b29bd5..016f03ee50 100644
--- a/sysdeps/aarch64/multiarch/memmove.c
+++ b/sysdeps/aarch64/multiarch/memmove.c
@@ -30,9 +30,14 @@ extern __typeof (__redirect_memmove) __libc_memmove;
 
 extern __typeof (__redirect_memmove) __memmove_generic attribute_hidden;
 extern __typeof (__redirect_memmove) __memmove_thunderx attribute_hidden;
+extern __typeof (__redirect_memmove) __memmove_falkor attribute_hidden;
 
 libc_ifunc (__libc_memmove,
-            IS_THUNDERX (midr) ? __memmove_thunderx : __memmove_generic);
+            (IS_THUNDERX (midr)
+	     ? __memmove_thunderx
+	     : (IS_FALKOR (midr)
+		? __memmove_falkor
+		: __memmove_generic)));
 
 # undef memmove
 strong_alias (__libc_memmove, memmove);
diff --git a/sysdeps/aarch64/multiarch/memmove_falkor.S b/sysdeps/aarch64/multiarch/memmove_falkor.S
new file mode 100644
index 0000000000..3a4e6a2a8e
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memmove_falkor.S
@@ -0,0 +1,232 @@
+/* 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 <sysdep.h>
+
+/* Assumptions: ARMv8-a, AArch64, falkor, unaligned accesses.  */
+
+#define dstin	x0
+#define src	x1
+#define count	x2
+#define dstlen	x3
+#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 tmp1	x14
+
+/* Alias with A_l and A_h to train the prefetcher.  */
+#define Q_l	x22
+#define Q_h	x23
+
+/* RATIONALE:
+
+   The copy has 4 distinct parts:
+   * Small copies of 16 bytes and under
+   * Medium sized copies of 17-96 bytes
+   * Large copies where the source address is higher than the destination
+     (forward copies)
+   * Large copies where the destination address is higher than the source
+     (copy backward, or move).
+
+   We use only two registerpairs x6,x7 and x22,x23 for the copies and copy 32
+   bytes at a time to correctly train the hardware prefetcher for better
+   throughput.  */
+ENTRY_ALIGN (__memmove_falkor, 6)
+
+	sub	tmp1, dstin, src
+	add	srcend, src, count
+	add	dstend, dstin, count
+	cmp	count, 96
+	ccmp	tmp1, count, 2, hi
+	b.lo	L(move_long)
+
+	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:
+	/* 4-7 */
+	tbz	count, 2, 1f
+	ldr	A_lw, [src]
+	ldr	A_hw, [srcend, -4]
+	str	A_lw, [dstin]
+	str	A_hw, [dstend, -4]
+	ret
+	.p2align 4
+1:
+	/* 2-3 */
+	tbz	count, 1, 1f
+	ldrh	A_lw, [src]
+	ldrh	A_hw, [srcend, -2]
+	strh	A_lw, [dstin]
+	strh	A_hw, [dstend, -2]
+	ret
+	.p2align 4
+1:
+	/* 0-1 */
+	tbz	count, 0, 1f
+	ldrb	A_lw, [src]
+	strb	A_lw, [dstin]
+1:	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 SRC 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 32 bytes per iteration and prefetches one iteration ahead.  */
+
+	.p2align 4
+L(copy_long):
+	sub	count, count, 64 + 16	/* Test and readjust count.  */
+	mov	B_l, Q_l
+	mov	B_h, Q_h
+	ldp	A_l, A_h, [src]
+	and	tmp1, src, 15
+	bic	src, src, 15
+	sub	dst, dstin, tmp1
+	add	count, count, tmp1	/* Count is now 16 too large.  */
+	ldp	Q_l, Q_h, [src, 16]!
+	stp	A_l, A_h, [dstin]
+	ldp	A_l, A_h, [src, 16]!
+
+L(loop64):
+	subs	count, count, 32
+	stp	Q_l, Q_h, [dst, 16]
+	ldp	Q_l, Q_h, [src, 16]!
+	stp	A_l, A_h, [dst, 32]!
+	ldp	A_l, A_h, [src, 16]!
+	b.hi	L(loop64)
+
+	/* Write the last full set of 32 bytes.  The remainder is at most 32
+	   bytes, so it is safe to always copy 32 bytes from the end even if
+	   there is just 1 byte left.  */
+L(last64):
+	ldp	C_l, C_h, [srcend, -32]
+	stp	Q_l, Q_h, [dst, 16]
+	ldp	Q_l, Q_h, [srcend, -16]
+	stp	A_l, A_h, [dst, 32]
+	stp	C_l, C_h, [dstend, -32]
+	stp	Q_l, Q_h, [dstend, -16]
+	mov	Q_l, B_l
+	mov	Q_h, B_h
+	ret
+
+	.p2align 4
+L(move_long):
+	cbz	tmp1, 3f
+
+	mov	B_l, Q_l
+	mov	B_h, Q_h
+
+	/* Align SRCEND 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 32 bytes per iteration and prefetches one iteration ahead.  */
+
+	ldp	A_l, A_h, [srcend, -16]
+	and	tmp1, srcend, 15
+	sub	srcend, srcend, tmp1
+	ldp	Q_l, Q_h, [srcend, -16]!
+	stp	A_l, A_h, [dstend, -16]
+	sub	count, count, tmp1
+	ldp	A_l, A_h, [srcend, -16]!
+	sub	dstend, dstend, tmp1
+	sub	count, count, 64
+
+1:
+	subs	count, count, 32
+	stp	Q_l, Q_h, [dstend, -16]
+	ldp	Q_l, Q_h, [srcend, -16]!
+	stp	A_l, A_h, [dstend, -32]!
+	ldp	A_l, A_h, [srcend, -16]!
+	b.hi	1b
+
+	/* Write the last full set of 32 bytes.  The remainder is at most 32
+	   bytes, so it is safe to always copy 32 bytes from the start even if
+	   there is just 1 byte left.  */
+2:
+	ldp	C_l, C_h, [src, 16]
+	stp	Q_l, Q_h, [dstend, -16]
+	ldp	Q_l, Q_h, [src]
+	stp	A_l, A_h, [dstend, -32]
+	stp	C_l, C_h, [dstin, 16]
+	stp	Q_l, Q_h, [dstin]
+	mov	Q_l, B_l
+	mov	Q_h, B_h
+3:	ret
+
+END (__memmove_falkor)
+libc_hidden_builtin_def (__memmove_falkor)