S390: Optimize strncpy and wcsncpy.

This patch provides optimized versions of strncpy and wcsncpy with the z13
vector instructions.

ChangeLog:

	* sysdeps/s390/multiarch/strncpy-vx.S: New File.
	* sysdeps/s390/multiarch/strncpy.c: Likewise.
	* sysdeps/s390/multiarch/wcsncpy-c.c: Likewise.
	* sysdeps/s390/multiarch/wcsncpy-vx.S: Likewise.
	* sysdeps/s390/multiarch/wcsncpy.c: Likewise.
	* sysdeps/s390/s390-32/multiarch/strncpy.c: Likewise.
	* sysdeps/s390/s390-64/multiarch/strncpy.c: Likewise.
	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strncpy and
	wcsncpy functions.
	* wcsmbs/wcsncpy.c: Use WCSNCPY if defined.
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Add ifunc test for strncpy, wcsncpy.
	* string/test-strncpy.c: Add wcsncpy support.
	* wcsmbs/test-wcsncpy.c: New File.
	* wcsmbs/Makefile (strop-tests): Add wcsncpy.
	* benchtests/bench-strncpy.c: Add wcsncpy support.
	* benchtests/bench-wcsncpy.c: New File.
	* benchtests/Makefile (wcsmbs-bench): Add wcsncpy

17 files changed, 782 insertions, 87 deletions

diff --git a/ChangeLog b/ChangeLog
index 90cd456f1f..5cf5cf74e6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,26 @@
 2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
+	* sysdeps/s390/multiarch/strncpy-vx.S: New File.
+	* sysdeps/s390/multiarch/strncpy.c: Likewise.
+	* sysdeps/s390/multiarch/wcsncpy-c.c: Likewise.
+	* sysdeps/s390/multiarch/wcsncpy-vx.S: Likewise.
+	* sysdeps/s390/multiarch/wcsncpy.c: Likewise.
+	* sysdeps/s390/s390-32/multiarch/strncpy.c: Likewise.
+	* sysdeps/s390/s390-64/multiarch/strncpy.c: Likewise.
+	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strncpy and
+	wcsncpy functions.
+	* wcsmbs/wcsncpy.c: Use WCSNCPY if defined.
+	* sysdeps/s390/multiarch/ifunc-impl-list.c
+	(__libc_ifunc_impl_list): Add ifunc test for strncpy, wcsncpy.
+	* string/test-strncpy.c: Add wcsncpy support.
+	* wcsmbs/test-wcsncpy.c: New File.
+	* wcsmbs/Makefile (strop-tests): Add wcsncpy.
+	* benchtests/bench-strncpy.c: Add wcsncpy support.
+	* benchtests/bench-wcsncpy.c: New File.
+	* benchtests/Makefile (wcsmbs-bench): Add wcsncpy
+
+2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
 	* sysdeps/s390/multiarch/stpcpy-c.c: New File.
 	* sysdeps/s390/multiarch/stpcpy-vx.S: Likewise.
 	* sysdeps/s390/multiarch/stpcpy.c: Likewise.
diff --git a/benchtests/Makefile b/benchtests/Makefile
index bf1f6dca36..37853287b8 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -36,7 +36,7 @@ string-bench := bcopy bzero memccpy memchr memcmp memcpy memmem memmove \
 		strncasecmp strncat strncmp strncpy strnlen strpbrk strrchr \
 		strspn strstr strcpy_chk stpcpy_chk memrchr strsep strtok \
 		strcoll
-wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy
+wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy wcsncpy
 string-bench-all := $(string-bench) ${wcsmbs-bench}
 
 # We have to generate locales
diff --git a/benchtests/bench-strncpy.c b/benchtests/bench-strncpy.c
index 517daa0d98..de1e2af3e3 100644
--- a/benchtests/bench-strncpy.c
+++ b/benchtests/bench-strncpy.c
@@ -16,23 +16,56 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifdef WIDE
+# include <wchar.h>
+# define CHAR wchar_t
+# define UCHAR wchar_t
+# define BIG_CHAR WCHAR_MAX
+# define SMALL_CHAR 1273
+# define MEMCMP wmemcmp
+# define MEMSET wmemset
+# define STRNLEN wcsnlen
+#else
+# define CHAR char
+# define UCHAR unsigned char
+# define BIG_CHAR CHAR_MAX
+# define SMALL_CHAR 127
+# define MEMCMP memcmp
+# define MEMSET memset
+# define STRNLEN strnlen
+#endif /* !WIDE */
+
+
 #ifndef STRNCPY_RESULT
 # define STRNCPY_RESULT(dst, len, n) dst
 # define TEST_MAIN
-# define TEST_NAME "strncpy"
+# ifndef WIDE
+#  define TEST_NAME "strncpy"
+# else
+#  define TEST_NAME "wcsncpy"
+# endif /* WIDE */
 # include "bench-string.h"
-
-char *simple_strncpy (char *, const char *, size_t);
-char *stupid_strncpy (char *, const char *, size_t);
-
-IMPL (stupid_strncpy, 0)
-IMPL (simple_strncpy, 0)
-IMPL (strncpy, 1)
-
-char *
-simple_strncpy (char *dst, const char *src, size_t n)
+# ifndef WIDE
+#  define SIMPLE_STRNCPY simple_strncpy
+#  define STUPID_STRNCPY stupid_strncpy
+#  define STRNCPY strncpy
+# else
+#  define SIMPLE_STRNCPY simple_wcsncpy
+#  define STUPID_STRNCPY stupid_wcsncpy
+#  define STRNCPY wcsncpy
+# endif /* WIDE */
+
+CHAR *SIMPLE_STRNCPY (CHAR *, const CHAR *, size_t);
+CHAR *STUPID_STRNCPY (CHAR *, const CHAR *, size_t);
+
+IMPL (STUPID_STRNCPY, 0)
+IMPL (SIMPLE_STRNCPY, 0)
+IMPL (STRNCPY, 1)
+
+CHAR *
+SIMPLE_STRNCPY (CHAR *dst, const CHAR *src, size_t n)
 {
-  char *ret = dst;
+  CHAR *ret = dst;
   while (n--)
     if ((*dst++ = *src++) == '\0')
       {
@@ -43,10 +76,10 @@ simple_strncpy (char *dst, const char *src, size_t n)
   return ret;
 }
 
-char *
-stupid_strncpy (char *dst, const char *src, size_t n)
+CHAR *
+STUPID_STRNCPY (CHAR *dst, const CHAR *src, size_t n)
 {
-  size_t nc = strnlen (src, n);
+  size_t nc = STRNLEN (src, n);
   size_t i;
 
   for (i = 0; i < nc; ++i)
@@ -55,12 +88,12 @@ stupid_strncpy (char *dst, const char *src, size_t n)
     dst[i] = '\0';
   return dst;
 }
-#endif
+#endif /* !STRNCPY_RESULT */
 
-typedef char *(*proto_t) (char *, const char *, size_t);
+typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
 
 static void
-do_one_test (impl_t *impl, char *dst, const char *src, size_t len, size_t n)
+do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t len, size_t n)
 {
   size_t i, iters = INNER_LOOP_ITERS;
   timing_t start, stop, cur;
@@ -73,7 +106,7 @@ do_one_test (impl_t *impl, char *dst, const char *src, size_t len, size_t n)
       return;
     }
 
-  if (memcmp (dst, src, len > n ? n : len) != 0)
+  if (memcmp (dst, src, (len > n ? n : len) * sizeof (CHAR)) != 0)
     {
       error (0, 0, "Wrong result in function %s", impl->name);
       ret = 1;
@@ -109,23 +142,26 @@ static void
 do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char)
 {
   size_t i;
-  char *s1, *s2;
+  CHAR *s1, *s2;
 
+/* For wcsncpy: align1 and align2 here mean alignment not in bytes,
+   but in wchar_ts, in bytes it will equal to align * (sizeof (wchar_t)).  */
   align1 &= 7;
-  if (align1 + len >= page_size)
+  if ((align1 + len) * sizeof (CHAR) >= page_size)
     return;
 
   align2 &= 7;
-  if (align2 + len >= page_size)
+  if ((align2 + len) * sizeof (CHAR) >= page_size)
     return;
 
-  s1 = (char *) (buf1 + align1);
-  s2 = (char *) (buf2 + align2);
+  s1 = (CHAR *) (buf1) + align1;
+  s2 = (CHAR *) (buf2) + align2;
 
   for (i = 0; i < len; ++i)
     s1[i] = 32 + 23 * i % (max_char - 32);
   s1[len] = 0;
-  for (i = len + 1; i + align1 < page_size && i < len + 64; ++i)
+  for (i = len + 1; (i + align1) * sizeof (CHAR) < page_size && i < len + 64;
+       ++i)
     s1[i] = 32 + 32 * i % (max_char - 32);
 
   printf ("Length %4zd, n %4zd, alignment %2zd/%2zd:", len, n, align1, align2);
@@ -150,22 +186,22 @@ test_main (void)
 
   for (i = 1; i < 8; ++i)
     {
-      do_test (i, i, 16, 16, 127);
-      do_test (i, i, 16, 16, 255);
-      do_test (i, 2 * i, 16, 16, 127);
-      do_test (2 * i, i, 16, 16, 255);
-      do_test (8 - i, 2 * i, 1 << i, 2 << i, 127);
-      do_test (2 * i, 8 - i, 2 << i, 1 << i, 127);
-      do_test (8 - i, 2 * i, 1 << i, 2 << i, 255);
-      do_test (2 * i, 8 - i, 2 << i, 1 << i, 255);
+      do_test (i, i, 16, 16, SMALL_CHAR);
+      do_test (i, i, 16, 16, BIG_CHAR);
+      do_test (i, 2 * i, 16, 16, SMALL_CHAR);
+      do_test (2 * i, i, 16, 16, BIG_CHAR);
+      do_test (8 - i, 2 * i, 1 << i, 2 << i, SMALL_CHAR);
+      do_test (2 * i, 8 - i, 2 << i, 1 << i, SMALL_CHAR);
+      do_test (8 - i, 2 * i, 1 << i, 2 << i, BIG_CHAR);
+      do_test (2 * i, 8 - i, 2 << i, 1 << i, BIG_CHAR);
     }
 
   for (i = 1; i < 8; ++i)
     {
-      do_test (0, 0, 4 << i, 8 << i, 127);
-      do_test (0, 0, 16 << i, 8 << i, 127);
-      do_test (8 - i, 2 * i, 4 << i, 8 << i, 127);
-      do_test (8 - i, 2 * i, 16 << i, 8 << i, 127);
+      do_test (0, 0, 4 << i, 8 << i, SMALL_CHAR);
+      do_test (0, 0, 16 << i, 8 << i, SMALL_CHAR);
+      do_test (8 - i, 2 * i, 4 << i, 8 << i, SMALL_CHAR);
+      do_test (8 - i, 2 * i, 16 << i, 8 << i, SMALL_CHAR);
     }
 
   return ret;
diff --git a/benchtests/bench-wcsncpy.c b/benchtests/bench-wcsncpy.c
new file mode 100644
index 0000000000..d6f63c9393
--- /dev/null
+++ b/benchtests/bench-wcsncpy.c
@@ -0,0 +1,20 @@
+/* Measure wcsncpy functions.
+   Copyright (C) 2015 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 WIDE 1
+#include "bench-strncpy.c"
diff --git a/string/test-strncpy.c b/string/test-strncpy.c
index d1c312a3a2..f10a3ab17f 100644
--- a/string/test-strncpy.c
+++ b/string/test-strncpy.c
@@ -1,4 +1,4 @@
-/* Test and measure strncpy functions.
+/* Test strncpy functions.
    Copyright (C) 1999-2015 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Written by Jakub Jelinek <jakub@redhat.com>, 1999.
@@ -17,23 +17,56 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifdef WIDE
+# include <wchar.h>
+# define CHAR wchar_t
+# define UCHAR wchar_t
+# define BIG_CHAR WCHAR_MAX
+# define SMALL_CHAR 1273
+# define MEMCMP wmemcmp
+# define MEMSET wmemset
+# define STRNLEN wcsnlen
+#else
+# define CHAR char
+# define UCHAR unsigned char
+# define BIG_CHAR CHAR_MAX
+# define SMALL_CHAR 127
+# define MEMCMP memcmp
+# define MEMSET memset
+# define STRNLEN strnlen
+#endif /* !WIDE */
+
+
 #ifndef STRNCPY_RESULT
 # define STRNCPY_RESULT(dst, len, n) dst
 # define TEST_MAIN
-# define TEST_NAME "strncpy"
+# ifndef WIDE
+#  define TEST_NAME "strncpy"
+# else
+#  define TEST_NAME "wcsncpy"
+# endif /* WIDE */
 # include "test-string.h"
+# ifndef WIDE
+#  define SIMPLE_STRNCPY simple_strncpy
+#  define STUPID_STRNCPY stupid_strncpy
+#  define STRNCPY strncpy
+# else
+#  define SIMPLE_STRNCPY simple_wcsncpy
+#  define STUPID_STRNCPY stupid_wcsncpy
+#  define STRNCPY wcsncpy
+# endif /* WIDE */
 
-char *simple_strncpy (char *, const char *, size_t);
-char *stupid_strncpy (char *, const char *, size_t);
+CHAR *SIMPLE_STRNCPY (CHAR *, const CHAR *, size_t);
+CHAR *STUPID_STRNCPY (CHAR *, const CHAR *, size_t);
 
-IMPL (stupid_strncpy, 0)
-IMPL (simple_strncpy, 0)
-IMPL (strncpy, 1)
+IMPL (STUPID_STRNCPY, 0)
+IMPL (SIMPLE_STRNCPY, 0)
+IMPL (STRNCPY, 1)
 
-char *
-simple_strncpy (char *dst, const char *src, size_t n)
+CHAR *
+SIMPLE_STRNCPY (CHAR *dst, const CHAR *src, size_t n)
 {
-  char *ret = dst;
+  CHAR *ret = dst;
   while (n--)
     if ((*dst++ = *src++) == '\0')
       {
@@ -44,10 +77,10 @@ simple_strncpy (char *dst, const char *src, size_t n)
   return ret;
 }
 
-char *
-stupid_strncpy (char *dst, const char *src, size_t n)
+CHAR *
+STUPID_STRNCPY (CHAR *dst, const CHAR *src, size_t n)
 {
-  size_t nc = strnlen (src, n);
+  size_t nc = STRNLEN (src, n);
   size_t i;
 
   for (i = 0; i < nc; ++i)
@@ -56,12 +89,12 @@ stupid_strncpy (char *dst, const char *src, size_t n)
     dst[i] = '\0';
   return dst;
 }
-#endif
+#endif /* !STRNCPY_RESULT */
 
-typedef char *(*proto_t) (char *, const char *, size_t);
+typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
 
 static void
-do_one_test (impl_t *impl, char *dst, const char *src, size_t len, size_t n)
+do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t len, size_t n)
 {
   if (CALL (impl, dst, src, n) != STRNCPY_RESULT (dst, len, n))
     {
@@ -71,7 +104,7 @@ do_one_test (impl_t *impl, char *dst, const char *src, size_t len, size_t n)
       return;
     }
 
-  if (memcmp (dst, src, len > n ? n : len) != 0)
+  if (memcmp (dst, src, (len > n ? n : len) * sizeof (CHAR)) != 0)
     {
       error (0, 0, "Wrong result in function %s", impl->name);
       ret = 1;
@@ -96,23 +129,26 @@ static void
 do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char)
 {
   size_t i;
-  char *s1, *s2;
+  CHAR *s1, *s2;
 
+/* For wcsncpy: align1 and align2 here mean alignment not in bytes,
+   but in wchar_ts, in bytes it will equal to align * (sizeof (wchar_t)).  */
   align1 &= 7;
-  if (align1 + len >= page_size)
+  if ((align1 + len) * sizeof (CHAR) >= page_size)
     return;
 
   align2 &= 7;
-  if (align2 + len >= page_size)
+  if ((align2 + len) * sizeof (CHAR) >= page_size)
     return;
 
-  s1 = (char *) (buf1 + align1);
-  s2 = (char *) (buf2 + align2);
+  s1 = (CHAR *) (buf1) + align1;
+  s2 = (CHAR *) (buf2) + align2;
 
   for (i = 0; i < len; ++i)
     s1[i] = 32 + 23 * i % (max_char - 32);
   s1[len] = 0;
-  for (i = len + 1; i + align1 < page_size && i < len + 64; ++i)
+  for (i = len + 1; (i + align1) * sizeof (CHAR) < page_size && i < len + 64;
+       ++i)
     s1[i] = 32 + 32 * i % (max_char - 32);
 
   FOR_EACH_IMPL (impl, 0)
@@ -123,12 +159,16 @@ static void
 do_random_tests (void)
 {
   size_t i, j, n, align1, align2, len, size, mode;
-  unsigned char *p1 = buf1 + page_size - 512;
-  unsigned char *p2 = buf2 + page_size - 512;
-  unsigned char *res;
+  UCHAR *p1 = (UCHAR *) (buf1 + page_size) - 512;
+  UCHAR *p2 = (UCHAR *) (buf2 + page_size) - 512;
+  UCHAR *res;
 
   for (n = 0; n < ITERATIONS; n++)
     {
+      /* For wcsncpy: align1 and align2 here mean align not in bytes,
+	 but in wchar_ts, in bytes it will equal to align * (sizeof
+	 (wchar_t)).  */
+
       mode = random ();
       if (mode & 1)
 	{
@@ -166,7 +206,7 @@ do_random_tests (void)
 	    {
 	      size = random () & 511;
 	      if (size + j > 512)
-		size = 512 - j - (random() & 31);
+		size = 512 - j - (random () & 31);
 	    }
 	  else
 	    size = 512 - j;
@@ -182,18 +222,17 @@ do_random_tests (void)
 	    p1[i] = 0;
 	  else
 	    {
-	      p1[i] = random () & 255;
+	      p1[i] = random () & BIG_CHAR;
 	      if (i >= align1 && i < len + align1 && !p1[i])
-		p1[i] = (random () & 127) + 3;
+		p1[i] = (random () & SMALL_CHAR) + 3;
 	    }
 	}
 
       FOR_EACH_IMPL (impl, 1)
 	{
-	  memset (p2 - 64, '\1', 512 + 64);
-	  res = (unsigned char *) CALL (impl,
-					(char *) (p2 + align2),
-					(char *) (p1 + align1), size);
+	  MEMSET (p2 - 64, '\1', 512 + 64);
+	  res = (UCHAR *) CALL (impl, (CHAR *) (p2 + align2),
+				(CHAR *) (p1 + align1), size);
 	  if (res != STRNCPY_RESULT (p2 + align2, len, size))
 	    {
 	      error (0, 0, "Iteration %zd - wrong result in function %s (%zd, %zd, %zd) %p != %p",
@@ -235,7 +274,7 @@ do_random_tests (void)
 	  j = len + 1;
 	  if (size < j)
 	    j = size;
-	  if (memcmp (p1 + align1, p2 + align2, j))
+	  if (MEMCMP (p1 + align1, p2 + align2, j))
 	    {
 	      error (0, 0, "Iteration %zd - different strings, %s (%zd, %zd, %zd)",
 		     n, impl->name, align1, align2, len);
@@ -259,22 +298,22 @@ test_main (void)
 
   for (i = 1; i < 8; ++i)
     {
-      do_test (i, i, 16, 16, 127);
-      do_test (i, i, 16, 16, 255);
-      do_test (i, 2 * i, 16, 16, 127);
-      do_test (2 * i, i, 16, 16, 255);
-      do_test (8 - i, 2 * i, 1 << i, 2 << i, 127);
-      do_test (2 * i, 8 - i, 2 << i, 1 << i, 127);
-      do_test (8 - i, 2 * i, 1 << i, 2 << i, 255);
-      do_test (2 * i, 8 - i, 2 << i, 1 << i, 255);
+      do_test (i, i, 16, 16, SMALL_CHAR);
+      do_test (i, i, 16, 16, BIG_CHAR);
+      do_test (i, 2 * i, 16, 16, SMALL_CHAR);
+      do_test (2 * i, i, 16, 16, BIG_CHAR);
+      do_test (8 - i, 2 * i, 1 << i, 2 << i, SMALL_CHAR);
+      do_test (2 * i, 8 - i, 2 << i, 1 << i, SMALL_CHAR);
+      do_test (8 - i, 2 * i, 1 << i, 2 << i, BIG_CHAR);
+      do_test (2 * i, 8 - i, 2 << i, 1 << i, BIG_CHAR);
     }
 
   for (i = 1; i < 8; ++i)
     {
-      do_test (0, 0, 4 << i, 8 << i, 127);
-      do_test (0, 0, 16 << i, 8 << i, 127);
-      do_test (8 - i, 2 * i, 4 << i, 8 << i, 127);
-      do_test (8 - i, 2 * i, 16 << i, 8 << i, 127);
+      do_test (0, 0, 4 << i, 8 << i, SMALL_CHAR);
+      do_test (0, 0, 16 << i, 8 << i, SMALL_CHAR);
+      do_test (8 - i, 2 * i, 4 << i, 8 << i, SMALL_CHAR);
+      do_test (8 - i, 2 * i, 16 << i, 8 << i, SMALL_CHAR);
     }
 
   do_random_tests ();
diff --git a/sysdeps/s390/multiarch/Makefile b/sysdeps/s390/multiarch/Makefile
index 5b5734271b..0dff2dcdf1 100644
--- a/sysdeps/s390/multiarch/Makefile
+++ b/sysdeps/s390/multiarch/Makefile
@@ -2,12 +2,14 @@ ifeq ($(subdir),string)
 sysdep_routines += strlen strlen-vx strlen-c \
 		   strnlen strnlen-vx strnlen-c \
 		   strcpy strcpy-vx \
-		   stpcpy stpcpy-vx stpcpy-c
+		   stpcpy stpcpy-vx stpcpy-c \
+		   strncpy strncpy-vx
 endif
 
 ifeq ($(subdir),wcsmbs)
 sysdep_routines += wcslen wcslen-vx wcslen-c \
 		   wcsnlen wcsnlen-vx wcsnlen-c \
 		   wcscpy wcscpy-vx wcscpy-c \
-		   wcpcpy wcpcpy-vx wcpcpy-c
+		   wcpcpy wcpcpy-vx wcpcpy-c \
+		   wcsncpy wcsncpy-vx wcsncpy-c
 endif
diff --git a/sysdeps/s390/multiarch/ifunc-impl-list.c b/sysdeps/s390/multiarch/ifunc-impl-list.c
index a4023010da..940421d0f8 100644
--- a/sysdeps/s390/multiarch/ifunc-impl-list.c
+++ b/sysdeps/s390/multiarch/ifunc-impl-list.c
@@ -91,6 +91,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
   IFUNC_VX_IMPL (stpcpy);
   IFUNC_VX_IMPL (wcpcpy);
 
+  IFUNC_VX_IMPL (strncpy);
+  IFUNC_VX_IMPL (wcsncpy);
+
 #endif /* HAVE_S390_VX_ASM_SUPPORT */
 
   return i;
diff --git a/sysdeps/s390/multiarch/strncpy-vx.S b/sysdeps/s390/multiarch/strncpy-vx.S
new file mode 100644
index 0000000000..0938280fee
--- /dev/null
+++ b/sysdeps/s390/multiarch/strncpy-vx.S
@@ -0,0 +1,207 @@
+/* Vector optimized 32/64 bit S/390 version of strncpy.
+   Copyright (C) 2015 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/>.  */
+
+#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+
+# include "sysdep.h"
+# include "asm-syntax.h"
+
+	.text
+
+/* char * strncpy (const char *dest, const char *src, size_t n)
+   Copy at most n characters of string  src to dest.
+
+   Register usage:
+   -r0=dest pointer for return
+   -r1=tmp, zero byte index
+   -r2=dest
+   -r3=src
+   -r4=n
+   -r5=current_len
+   -r6=tmp, loaded bytes
+   -r7=tmp, border
+   -v16=part of src
+   -v17=index of zero
+   -v18=part of src
+   -v31=register save area for r6, r7
+*/
+ENTRY(__strncpy_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+# if !defined __s390x__
+	llgfr	%r4,%r4
+# endif /* !defined __s390x__ */
+
+	clgfi	%r4,0
+	ber	%r14		/* Nothing to do, if n == 0.  */
+	lgr	%r0,%r2		/* Save destination pointer for return.  */
+	vlvgp	%v31,%r6,%r7	/* Save registers.  */
+
+	vlbb	%v16,0(%r3),6	/* Load s until next 4k-byte boundary.  */
+	lcbb	%r6,0(%r3),6	/* Get bytes to 4k-byte boundary or 16.  */
+	llgfr	%r6,%r6		/* Convert 32bit to 64bit.  */
+
+	lghi	%r5,0		/* current_len = 0.  */
+
+	clgrjle	%r4,%r6,.Lremaining_v16 /* If n <= loaded-bytes
+					   -> process remaining.  */
+
+	/* n > loaded-byte-count.  */
+	vfenezb	%v17,%v16,%v16	/* Find element not equal with zero search.  */
+	vlgvb	%r1,%v17,7	/* Load zero index or 16 if not found.  */
+	clrjl	%r1,%r6,.Lfound_v16_store /* Found zero within loaded bytes,
+					     copy and return.  */
+
+	/* Align s to 16 byte.  */
+	risbgn	%r7,%r3,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
+	lghi	%r5,15		/* current_len = 15.  */
+	slr	%r5,%r7		/* Compute highest index to 16byte boundary.  */
+
+	/* Zero not found and n > loaded-byte-count.  */
+	vstl	%v16,%r5,0(%r2)	/* Copy loaded characters - no zero.  */
+	ahi	%r5,1		/* Start loop at next character.  */
+
+	/* Now we are 16byte aligned, so we can load
+	   a full vreg without page fault.  */
+	lgr	%r1,%r5		/* If %r5 + 64 < maxlen? -> loop64.  */
+	aghi	%r1,64
+	clgrjl	%r1,%r4,.Lloop64
+
+	vl	%v16,0(%r5,%r3)	/* Load s.  */
+	clgijl	%r4,17,.Lremaining_v16	/* If n <= 16, process remaining
+					   bytes.  */
+.Llt64:
+	lgr	%r7,%r4
+	slgfi	%r7,16		/* border_len = n - 16.  */
+
+	clgrjhe	%r5,%r7,.Lremaining_v16 /* If current_len >= border
+					   then process remaining bytes.  */
+	vfenezbs %v17,%v16,%v16	/* Find element not equal with zero search.  */
+	je	.Lfound_v16	/* Jump away if zero was found.  */
+	vl	%v18,16(%r5,%r3) /* Load next part of s.  */
+	vst	%v16,0(%r5,%r2)	/* Store previous part without zero to dst.  */
+	aghi	%r5,16
+
+	clgrjhe	%r5,%r7,.Lremaining_v18
+	vfenezbs %v17,%v18,%v18
+	je	.Lfound_v18
+	vl	%v16,16(%r5,%r3)
+	vst	%v18,0(%r5,%r2)
+	aghi	%r5,16
+
+	clgrjhe	%r5,%r7,.Lremaining_v16
+	vfenezbs %v17,%v16,%v16
+	je	.Lfound_v16
+	vl	%v18,16(%r5,%r3)
+	vst	%v16,0(%r5,%r2)
+	aghi	%r5,16
+
+.Lremaining_v18:
+	vlr	%v16,%v18
+.Lremaining_v16:
+	/* v16 contains the remaining bytes [1...16].
+	   Store remaining bytes and append string-termination.  */
+	vfenezb	%v17,%v16,%v16	/* Find element not equal with zero search.  */
+	slgrk	%r7,%r4,%r5	/* Remaining bytes = maxlen - current_len.  */
+	aghi	%r7,-1		/* vstl needs highest index.  */
+	la	%r2,0(%r5,%r2)	/* vstl has no index register.  */
+	vlgvb	%r1,%v17,7	/* Load zero index or 16 if not found.  */
+	/* Zero in remaining bytes? -> jump away (zero-index < max-index)
+	   Do not jump away if zero-index == max-index,
+	   but simply copy zero with vstl below.  */
+	clrjl	%r1,%r7,.Lfound_v16_store
+	vstl	%v16,%r7,0(%r2)	/* Store remaining bytes without null
+				   termination!.  */
+.Lend:
+	/* Restore saved registers.  */
+	vlgvg	%r6,%v31,0
+	vlgvg	%r7,%v31,1
+	lgr	%r2,%r0		/* Load saved dest-ptr.  */
+	br	%r14
+
+
+.Lfound_v16_32:
+	aghi	%r5,32
+	j	.Lfound_v16
+.Lfound_v18_48:
+	aghi	%r5,32
+.Lfound_v18_16:
+	aghi	%r5,16
+.Lfound_v18:
+	vlr	%v16,%v18
+.Lfound_v16:
+	/* v16 contains a zero. Store remaining bytes to zero. current_len
+	   has not reached border, thus checking for n is not needed! */
+	vlgvb	%r1,%v17,7	/* Load byte index of zero.  */
+	la	%r2,0(%r5,%r2)	/* vstl has no support for index-register.  */
+.Lfound_v16_store:
+	vstl	%v16,%r1,0(%r2)	/* Copy characters including zero.  */
+	/* Fill remaining bytes with zero - remaining count always > 0.  */
+	algr	%r5,%r1		/* Remaining bytes (=%r4) = ...  */
+	slgr	%r4,%r5		/* = n - (current_len + zero_index + 1).  */
+	la	%r2,0(%r1,%r2)	/* Pointer to zero. start filling beyond.  */
+	aghi	%r4,-2		/* mvc with exrl needs count - 1.
+				   (additional -1, see remaining bytes above) */
+	srlg	%r6,%r4,8	/* Split into 256 byte blocks.  */
+	ltgr	%r6,%r6
+	je	.Lzero_lt256
+.Lzero_loop256:
+	mvc	1(256,%r2),0(%r2) /* Fill 256 zeros at once.  */
+	la	%r2,256(%r2)
+	brctg	%r6,.Lzero_loop256 /* Loop until all blocks are processed.  */
+.Lzero_lt256:
+	exrl	%r4,.Lmvc_lt256
+	j	.Lend
+.Lmvc_lt256:
+	mvc	1(1,%r2),0(%r2)
+
+.Lloop64:
+	vl	%v16,0(%r5,%r3)	/* Load s.  */
+	vfenezbs %v17,%v16,%v16	/* Find element not equal with zero search.  */
+	je	.Lfound_v16	/* Jump away if zero was found.  */
+	vl	%v18,16(%r5,%r3) /* Load next part of s.  */
+	vst	%v16,0(%r5,%r2)	/* Store previous part without zero to dst.  */
+	vfenezbs %v17,%v18,%v18
+	je	.Lfound_v18_16
+	vl	%v16,32(%r5,%r3)
+	vst	%v18,16(%r5,%r2)
+	vfenezbs %v17,%v16,%v16
+	je	.Lfound_v16_32
+	vl	%v18,48(%r5,%r3)
+	vst	%v16,32(%r5,%r2)
+	vfenezbs %v17,%v18,%v18
+	je	.Lfound_v18_48
+	vst	%v18,48(%r5,%r2)
+
+	aghi	%r5,64
+	lgr	%r1,%r5		/* If %r5 + 64 < maxlen? -> loop64.  */
+	aghi	%r1,64
+	clgrjl	%r1,%r4,.Lloop64
+
+	vl	%v16,0(%r5,%r3)	/* Load s.  */
+	j	.Llt64
+END(__strncpy_vx)
+
+# define strncpy __strncpy_c
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(name) strong_alias(__strncpy_c, __GI_strncpy)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
+
+/* Include strncpy-implementation in s390-32/s390-64 subdirectory.  */
+#include <strncpy.S>
diff --git a/sysdeps/s390/multiarch/strncpy.c b/sysdeps/s390/multiarch/strncpy.c
new file mode 100644
index 0000000000..c1b73d4ee4
--- /dev/null
+++ b/sysdeps/s390/multiarch/strncpy.c
@@ -0,0 +1,24 @@
+/* Multiple versions of strncpy.
+   Copyright (C) 2015 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/>.  */
+
+#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+# include <string.h>
+# include <ifunc-resolve.h>
+
+s390_vx_libc_ifunc2 (__strncpy, strncpy)
+#endif
diff --git a/sysdeps/s390/multiarch/wcsncpy-c.c b/sysdeps/s390/multiarch/wcsncpy-c.c
new file mode 100644
index 0000000000..b9ed28f50f
--- /dev/null
+++ b/sysdeps/s390/multiarch/wcsncpy-c.c
@@ -0,0 +1,25 @@
+/* Default wcsncpy implementation for S/390.
+   Copyright (C) 2015 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/>.  */
+
+#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+# define WCSNCPY  __wcsncpy_c
+
+# include <wchar.h>
+extern __typeof (__wcsncpy) __wcsncpy_c;
+# include <wcsmbs/wcsncpy.c>
+#endif
diff --git a/sysdeps/s390/multiarch/wcsncpy-vx.S b/sysdeps/s390/multiarch/wcsncpy-vx.S
new file mode 100644
index 0000000000..8d692c0c6e
--- /dev/null
+++ b/sysdeps/s390/multiarch/wcsncpy-vx.S
@@ -0,0 +1,223 @@
+/* Vector optimized 32/64 bit S/390 version of wcsncpy.
+   Copyright (C) 2015 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/>.  */
+
+#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+
+# include "sysdep.h"
+# include "asm-syntax.h"
+
+	.text
+
+/* wchar_t *wcsncpy (const wchar_t *dest, const wchar_t *src, size_t n)
+   Copy at most n characters of string  src to dest.
+
+   Register usage:
+   -r0=dest pointer for return
+   -r1=tmp, zero byte index
+   -r2=dest
+   -r3=src
+   -r4=n
+   -r5=current_len
+   -r6=tmp, loaded bytes
+   -r7=tmp, border
+   -v16=part of src
+   -v17=index of zero
+   -v18=part of src
+   -v31=register save area for r6, r7
+*/
+ENTRY(__wcsncpy_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+# if !defined __s390x__
+	llgfr	%r4,%r4
+# endif /* !defined __s390x__ */
+
+	clgfi	%r4,0
+	ber	%r14		/* Nothing to do, if n == 0.  */
+
+	vlbb	%v16,0(%r3),6	/* Load s until next 4k-byte boundary.  */
+
+	tmll	%r3,3		/* Test if s is 4-byte aligned?  */
+	jne	.Lfallback	/* And use common-code variant if not.  */
+
+	vlvgp	%v31,%r6,%r7	/* Save registers.  */
+	lgr	%r0,%r2		/* Save destination pointer for return.  */
+
+	lcbb	%r6,0(%r3),6	/* Get bytes to 4k-byte boundary or 16.  */
+	llgfr	%r6,%r6		/* Convert 32bit to 64bit.  */
+
+	lghi	%r5,0		/* current_len = 0.  */
+
+	/* Check range of maxlen and convert to byte-count.  */
+# ifdef __s390x__
+	tmhh	%r4,49152	/* Test bit 0 or 1 of n.  */
+	lghi	%r1,-4		/* Max byte-count is 18446744073709551612.  */
+# else
+	tmlh	%r4,49152	/* Test bit 0 or 1 of n.  */
+	llilf	%r1,4294967292	/* Max byte-count is 4294967292.  */
+# endif /* !__s390x__ */
+	sllg	%r4,%r4,2	/* Convert character-count to byte-count.  */
+	locgrne	%r4,%r1		/* Use max byte-count, if bit 0/1 was one.  */
+
+	clgrjle	%r4,%r6,.Lremaining_v16 /* If n <= loaded-bytes
+					   -> process remaining.  */
+
+	/* n > loaded-byte-count.  */
+	vfenezf	%v17,%v16,%v16	/* Find element not equal with zero search.  */
+	vlgvb	%r1,%v17,7	/* Load zero index or 16 if not found.  */
+	aghi	%r1,3		/* Also copy remaining bytes of zero.  */
+	clrjl	%r1,%r6,.Lfound_v16_store /* Found zero within loaded bytes,
+					     copy and return.  */
+
+	/* Align s to 16 byte.  */
+	risbgn	%r7,%r3,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
+	lghi	%r5,15		/* current_len = 15.  */
+	slr	%r5,%r7		/* Compute highest index to 16byte boundary.  */
+
+	/* Zero not found and n > loaded-byte-count.  */
+	vstl	%v16,%r5,0(%r2)	/* Copy loaded characters - no zero.  */
+	ahi	%r5,1		/* Start loop at next character.  */
+
+	/* Now we are 16byte aligned, so we can load
+	   a full vreg without page fault.  */
+	lgr	%r1,%r5		/* If %r5 + 64 < maxlen? -> loop64.  */
+	aghi	%r1,64
+	clgrjl	%r1,%r4,.Lloop64
+
+	vl	%v16,0(%r5,%r3)	/* Load s.  */
+	clgijl	%r4,17,.Lremaining_v16	/* If n <=16, process remaining
+					   bytes.  */
+.Llt64:
+	lgr	%r7,%r4
+	slgfi	%r7,16		/* border_len = maxlen - 16.  */
+
+	clgrjhe	%r5,%r7,.Lremaining_v16 /* If current_len >= border
+					       then process remaining bytes.  */
+	vfenezfs %v17,%v16,%v16	/* Find element not equal with zero search.  */
+	je	.Lfound_v16	/* Jump away if zero was found.  */
+	vl	%v18,16(%r5,%r3) /* Load next part of s.  */
+	vst	%v16,0(%r5,%r2)	/* Store previous part without zero to dst.  */
+	aghi	%r5,16
+
+	clgrjhe	%r5,%r7,.Lremaining_v18
+	vfenezfs %v17,%v18,%v18
+	je	.Lfound_v18
+	vl	%v16,16(%r5,%r3)
+	vst	%v18,0(%r5,%r2)
+	aghi	%r5,16
+
+	clgrjhe	%r5,%r7,.Lremaining_v16
+	vfenezfs %v17,%v16,%v16
+	je	.Lfound_v16
+	vl	%v18,16(%r5,%r3)
+	vst	%v16,0(%r5,%r2)
+	aghi	%r5,16
+
+.Lremaining_v18:
+	vlr	%v16,%v18
+.Lremaining_v16:
+	/* v16 contains the remaining bytes [1...16].
+	   Store remaining bytes and append string-termination.  */
+	vfenezf	%v17,%v16,%v16	/* Find element not equal with zero search.  */
+	slgrk	%r7,%r4,%r5	/* Remaining bytes = maxlen - current_len.  */
+	aghi	%r7,-1		/* vstl needs highest index.  */
+	la	%r2,0(%r5,%r2)	/* vstl has no index register.  */
+	vlgvb	%r1,%v17,7	/* Load zero index or 16 if not found.  */
+	aghi	%r1,3		/* Also copy remaining bytes of zero.  */
+	/* Zero in remaining bytes? -> jump away (zero-index < max-index)
+	   Do not jump away if zero-index == max-index,
+	   but simply copy zero with vstl below.  */
+	clrjl	%r1,%r7,.Lfound_v16_store
+	vstl	%v16,%r7,0(%r2)	/* Store remaining bytes without null
+				   termination!.  */
+.Lend:
+	/* Restore saved registers.  */
+	vlgvg	%r6,%v31,0
+	vlgvg	%r7,%v31,1
+	lgr	%r2,%r0		/* Load saved dest-ptr.  */
+	br	%r14
+
+.Lfound_v16_32:
+	aghi	%r5,32
+	j	.Lfound_v16
+.Lfound_v18_48:
+	aghi	%r5,32
+.Lfound_v18_16:
+	aghi	%r5,16
+.Lfound_v18:
+	vlr	%v16,%v18
+.Lfound_v16:
+	/* v16 contains a zero. Store remaining bytes to zero. current_len
+	   has not reached border, thus checking for n is not needed! */
+	vlgvb	%r1,%v17,7	/* Load byte index of zero.  */
+	la	%r2,0(%r5,%r2)	/* vstl has no support for index-register.  */
+	aghi	%r1,3		/* Also copy remaining bytes of zero.  */
+.Lfound_v16_store:
+	vstl	%v16,%r1,0(%r2)	/* Copy characters including zero.  */
+	/* Fill remaining bytes with zero - remaining count always > 0.  */
+	algr	%r5,%r1		/* Remaining bytes (=%r4) = ...  */
+	slgr	%r4,%r5		/* = maxlen - (currlen + zero_index + 1).  */
+	la	%r2,0(%r1,%r2)	/* Pointer to zero. start filling beyond.  */
+	aghi	%r4,-2		/* mvc with exrl needs count - 1.
+				   (additional -1, see remaining bytes above) */
+	srlg	%r6,%r4,8	/* Split into 256 byte blocks.  */
+	ltgr	%r6,%r6
+	je	.Lzero_lt256
+.Lzero_loop256:
+	mvc	1(256,%r2),0(%r2) /* Fill 256 zeros at once.  */
+	la	%r2,256(%r2)
+	brctg	%r6,.Lzero_loop256 /* Loop until all blocks are processed.  */
+.Lzero_lt256:
+	exrl	%r4,.Lmvc_lt256
+	j	.Lend
+.Lmvc_lt256:
+	mvc	1(1,%r2),0(%r2)
+
+	/* Find zero in 16byte aligned loop.  */
+.Lloop64:
+	vl	%v16,0(%r5,%r3) /* Load s.  */
+	vfenezfs %v17,%v16,%v16	/* Find element not equal with zero search.  */
+	je	.Lfound_v16	/* Jump away if zero was found.  */
+	vl	%v18,16(%r5,%r3) /* Load next part of s.  */
+	vst	%v16,0(%r5,%r2)	/* Store previous part without zero to dst.  */
+	vfenezfs %v17,%v18,%v18
+	je	.Lfound_v18_16
+	vl	%v16,32(%r5,%r3)
+	vst	%v18,16(%r5,%r2)
+	vfenezfs %v17,%v16,%v16
+	je	.Lfound_v16_32
+	vl	%v18,48(%r5,%r3)
+	vst	%v16,32(%r5,%r2)
+	vfenezfs %v17,%v18,%v18
+	je	.Lfound_v18_48
+	vst	%v18,48(%r5,%r2)
+
+	aghi	%r5,64
+	lgr	%r1,%r5		/* If %r5 + 64 < maxlen? -> loop64.  */
+	aghi	%r1,64
+	clgrjl	%r1,%r4,.Lloop64
+
+	vl	%v16,0(%r5,%r3)	/* Load s.  */
+	j	.Llt64
+
+.Lfallback:
+	jg	__wcsncpy_c
+END(__wcsncpy_vx)
+
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
diff --git a/sysdeps/s390/multiarch/wcsncpy.c b/sysdeps/s390/multiarch/wcsncpy.c
new file mode 100644
index 0000000000..3ab3476fca
--- /dev/null
+++ b/sysdeps/s390/multiarch/wcsncpy.c
@@ -0,0 +1,28 @@
+/* Multiple versions of wcsncpy.
+   Copyright (C) 2015 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/>.  */
+
+#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+# include <wchar.h>
+# include <ifunc-resolve.h>
+
+s390_vx_libc_ifunc (__wcsncpy)
+weak_alias (__wcsncpy, wcsncpy)
+
+#else
+# include <wcsmbs/wcsncpy.c>
+#endif /* !(defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)) */
diff --git a/sysdeps/s390/s390-32/multiarch/strncpy.c b/sysdeps/s390/s390-32/multiarch/strncpy.c
new file mode 100644
index 0000000000..bc9c336e75
--- /dev/null
+++ b/sysdeps/s390/s390-32/multiarch/strncpy.c
@@ -0,0 +1,21 @@
+/* Multiple versions of strncpy.
+   Copyright (C) 2015 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/>.  */
+
+/* This wrapper-file is needed, because otherwise file
+   sysdeps/s390/s390-[32|64]/strncpy.S will be used.  */
+#include <sysdeps/s390/multiarch/strncpy.c>
diff --git a/sysdeps/s390/s390-64/multiarch/strncpy.c b/sysdeps/s390/s390-64/multiarch/strncpy.c
new file mode 100644
index 0000000000..bc9c336e75
--- /dev/null
+++ b/sysdeps/s390/s390-64/multiarch/strncpy.c
@@ -0,0 +1,21 @@
+/* Multiple versions of strncpy.
+   Copyright (C) 2015 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/>.  */
+
+/* This wrapper-file is needed, because otherwise file
+   sysdeps/s390/s390-[32|64]/strncpy.S will be used.  */
+#include <sysdeps/s390/multiarch/strncpy.c>
diff --git a/wcsmbs/Makefile b/wcsmbs/Makefile
index 1112e05a62..426eab0e95 100644
--- a/wcsmbs/Makefile
+++ b/wcsmbs/Makefile
@@ -43,7 +43,7 @@ routines := wcscat wcschr wcscmp wcscpy wcscspn wcsdup wcslen wcsncat \
 	    mbrtoc16 c16rtomb
 
 strop-tests :=  wcscmp wcsncmp wmemcmp wcslen wcschr wcsrchr wcscpy wcsnlen \
-		wcpcpy
+		wcpcpy wcsncpy
 tests := tst-wcstof wcsmbs-tst1 tst-wcsnlen tst-btowc tst-mbrtowc \
 	 tst-wcrtomb tst-wcpncpy tst-mbsrtowcs tst-wchar-h tst-mbrtowc2 \
 	 tst-c16c32-1 wcsatcliff $(addprefix test-,$(strop-tests))
diff --git a/wcsmbs/test-wcsncpy.c b/wcsmbs/test-wcsncpy.c
new file mode 100644
index 0000000000..27de6f8e94
--- /dev/null
+++ b/wcsmbs/test-wcsncpy.c
@@ -0,0 +1,20 @@
+/* Test wcsncpy functions.
+   Copyright (C) 2015 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 WIDE 1
+#include "../string/test-strncpy.c"
diff --git a/wcsmbs/wcsncpy.c b/wcsmbs/wcsncpy.c
index 7016f41e71..5ee5ee6bde 100644
--- a/wcsmbs/wcsncpy.c
+++ b/wcsmbs/wcsncpy.c
@@ -18,6 +18,9 @@
 
 #include <wchar.h>
 
+#ifdef WCSNCPY
+# define __wcsncpy WCSNCPY
+#endif
 
 /* Copy no more than N wide-characters of SRC to DEST.	*/
 wchar_t *
@@ -83,4 +86,6 @@ __wcsncpy (dest, src, n)
 
   return s;
 }
+#ifndef WCSNCPY
 weak_alias (__wcsncpy, wcsncpy)
+#endif