diff --git a/libc/Android.mk b/libc/Android.mk
index d8c8f63..e260871 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -256,7 +256,6 @@
     upstream-freebsd/lib/libc/string/wcstok.c \
     upstream-freebsd/lib/libc/string/wmemchr.c \
     upstream-freebsd/lib/libc/string/wmemcpy.c \
-    upstream-freebsd/lib/libc/string/wmemmove.c \
     upstream-freebsd/lib/libc/string/wmemset.c \
 
 libc_upstream_netbsd_src_files := \
diff --git a/libc/arch-arm/arm.mk b/libc/arch-arm/arm.mk
index c509b83..7c423ab 100644
--- a/libc/arch-arm/arm.mk
+++ b/libc/arch-arm/arm.mk
@@ -24,6 +24,7 @@
     upstream-freebsd/lib/libc/string/wcslen.c \
     upstream-freebsd/lib/libc/string/wcsrchr.c \
     upstream-freebsd/lib/libc/string/wmemcmp.c \
+    upstream-freebsd/lib/libc/string/wmemmove.c \
     upstream-openbsd/lib/libc/string/bcopy.c \
     upstream-openbsd/lib/libc/string/stpcpy.c \
     upstream-openbsd/lib/libc/string/stpncpy.c \
diff --git a/libc/arch-arm64/arm64.mk b/libc/arch-arm64/arm64.mk
index 93b0b0b..cd8b6ea 100644
--- a/libc/arch-arm64/arm64.mk
+++ b/libc/arch-arm64/arm64.mk
@@ -14,7 +14,6 @@
     upstream-freebsd/lib/libc/string/wcslen.c \
     upstream-freebsd/lib/libc/string/wcsrchr.c \
     upstream-freebsd/lib/libc/string/wmemcmp.c \
-    upstream-openbsd/lib/libc/string/bcopy.c \
     upstream-openbsd/lib/libc/string/stpcpy.c \
     upstream-openbsd/lib/libc/string/stpncpy.c \
     upstream-openbsd/lib/libc/string/strcat.c \
diff --git a/libc/arch-arm64/generic/bionic/bcopy.S b/libc/arch-arm64/generic/bionic/bcopy.S
new file mode 100644
index 0000000..7079e8b
--- /dev/null
+++ b/libc/arch-arm64/generic/bionic/bcopy.S
@@ -0,0 +1,30 @@
+/* Copyright (c) 2014, Linaro Limited
+   All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in the
+         documentation and/or other materials provided with the distribution.
+       * Neither the name of the Linaro nor the
+         names of its contributors may be used to endorse or promote products
+         derived from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#define BCOPY
+#include "memmove.S"
+#undef BCOPY
diff --git a/libc/arch-arm64/generic/bionic/memmove.S b/libc/arch-arm64/generic/bionic/memmove.S
index d6ecb86..8b366a3 100644
--- a/libc/arch-arm64/generic/bionic/memmove.S
+++ b/libc/arch-arm64/generic/bionic/memmove.S
@@ -29,11 +29,16 @@
  *
  * ARMv8-a, AArch64
  * Unaligned accesses
+ * wchar_t is 4 bytes
  */
 
 #include <private/bionic_asm.h>
 
 /* Parameters and result.  */
+#ifdef BCOPY
+#define origdstin	x1
+#define origsrc	x0
+#endif
 #define dstin	x0
 #define src	x1
 #define count	x2
@@ -54,7 +59,18 @@
 #define D_l	x13
 #define D_h	x14
 
+#ifdef BCOPY
+ENTRY(bcopy)
+	/* Swap src and dst so that a branch to memcpy doesn't cause issues. */
+	mov	tmp1, origsrc
+	mov	origsrc, origdstin
+	mov	origdstin, tmp1
+#elif defined(WMEMMOVE)
+ENTRY(wmemmove)
+	lsl	count, count, #2
+#else
 ENTRY(memmove)
+#endif
 	cmp	dstin, src
 	b.lo	.Ldownwards
 	add	tmp1, src, count
@@ -316,4 +332,10 @@
 	tst	count, #0x3f
 	b.ne	.Ltail63down
 	ret
+#ifdef BCOPY
+END(bcopy)
+#elif defined(WMEMMOVE)
+END(wmemmove)
+#else
 END(memmove)
+#endif
diff --git a/libc/arch-arm64/generic/bionic/wmemmove.S b/libc/arch-arm64/generic/bionic/wmemmove.S
new file mode 100644
index 0000000..e4f67f7
--- /dev/null
+++ b/libc/arch-arm64/generic/bionic/wmemmove.S
@@ -0,0 +1,30 @@
+/* Copyright (c) 2014, Linaro Limited
+   All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in the
+         documentation and/or other materials provided with the distribution.
+       * Neither the name of the Linaro nor the
+         names of its contributors may be used to endorse or promote products
+         derived from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#define WMEMMOVE
+#include "memmove.S"
+#undef WMEMMOVE
diff --git a/libc/arch-arm64/generic/generic.mk b/libc/arch-arm64/generic/generic.mk
index 14920a6..2ecc90e 100644
--- a/libc/arch-arm64/generic/generic.mk
+++ b/libc/arch-arm64/generic/generic.mk
@@ -1,4 +1,5 @@
 libc_bionic_src_files_arm64 += \
+    arch-arm64/generic/bionic/bcopy.S \
     arch-arm64/generic/bionic/memcmp.S \
     arch-arm64/generic/bionic/memcpy.S \
     arch-arm64/generic/bionic/memmove.S \
@@ -7,3 +8,4 @@
     arch-arm64/generic/bionic/strlen.S \
     arch-arm64/generic/bionic/strncmp.S \
     arch-arm64/generic/bionic/strnlen.S \
+    arch-arm64/generic/bionic/wmemmove.S
diff --git a/libc/arch-mips/mips.mk b/libc/arch-mips/mips.mk
index 2c87a9e..0244712 100644
--- a/libc/arch-mips/mips.mk
+++ b/libc/arch-mips/mips.mk
@@ -26,6 +26,7 @@
     upstream-freebsd/lib/libc/string/wcslen.c \
     upstream-freebsd/lib/libc/string/wcsrchr.c \
     upstream-freebsd/lib/libc/string/wmemcmp.c \
+    upstream-freebsd/lib/libc/string/wmemmove.c \
     upstream-openbsd/lib/libc/string/bcopy.c \
     upstream-openbsd/lib/libc/string/stpcpy.c \
     upstream-openbsd/lib/libc/string/stpncpy.c \
diff --git a/libc/arch-mips64/mips64.mk b/libc/arch-mips64/mips64.mk
index 26390a6..5759104 100644
--- a/libc/arch-mips64/mips64.mk
+++ b/libc/arch-mips64/mips64.mk
@@ -16,6 +16,7 @@
     upstream-freebsd/lib/libc/string/wcslen.c \
     upstream-freebsd/lib/libc/string/wcsrchr.c \
     upstream-freebsd/lib/libc/string/wmemcmp.c \
+    upstream-freebsd/lib/libc/string/wmemmove.c \
     upstream-openbsd/lib/libc/string/bcopy.c \
     upstream-openbsd/lib/libc/string/stpcpy.c \
     upstream-openbsd/lib/libc/string/stpncpy.c \
diff --git a/libc/arch-x86/x86.mk b/libc/arch-x86/x86.mk
index aa183cb..d13a934 100644
--- a/libc/arch-x86/x86.mk
+++ b/libc/arch-x86/x86.mk
@@ -12,6 +12,7 @@
     bionic/__memset_chk.cpp \
     bionic/__strcpy_chk.cpp \
     bionic/__strcat_chk.cpp \
+    upstream-freebsd/lib/libc/string/wmemmove.c \
 
 
 # These are shared by all the 32-bit targets, but not the 64-bit ones.
diff --git a/libc/arch-x86_64/x86_64.mk b/libc/arch-x86_64/x86_64.mk
index e3c2562..c54cdb8 100644
--- a/libc/arch-x86_64/x86_64.mk
+++ b/libc/arch-x86_64/x86_64.mk
@@ -14,6 +14,7 @@
     upstream-freebsd/lib/libc/string/wcslen.c \
     upstream-freebsd/lib/libc/string/wcsrchr.c \
     upstream-freebsd/lib/libc/string/wmemcmp.c \
+    upstream-freebsd/lib/libc/string/wmemmove.c \
     upstream-openbsd/lib/libc/string/strlcat.c \
     upstream-openbsd/lib/libc/string/strlcpy.c \
 
diff --git a/tests/wchar_test.cpp b/tests/wchar_test.cpp
index 50b8608..5fa5bf9 100644
--- a/tests/wchar_test.cpp
+++ b/tests/wchar_test.cpp
@@ -442,3 +442,14 @@
   EXPECT_EQ(24U, wcsftime(buf, sizeof(buf), L"%c", &t));
   EXPECT_STREQ(L"Sun Mar 10 00:00:00 2100", buf);
 }
+
+TEST(wchar, wmemmove) {
+  const wchar_t const_wstr[] = L"This is a test of something or other.....";
+  wchar_t* wstr = new wchar_t[sizeof(const_wstr)];
+
+  wmemmove(wstr, const_wstr, sizeof(const_wstr)/sizeof(wchar_t));
+  EXPECT_STREQ(const_wstr, wstr);
+
+  wmemmove(wstr+5, wstr, sizeof(const_wstr)/sizeof(wchar_t) - 5);
+  EXPECT_STREQ(L"This This is a test of something or other.", wstr);
+}