S390: Optimize strncat wcsncat.

This patch provides optimized versions of strncat and wcsncat with the z13
vector instructions.

ChangeLog:

	* sysdeps/s390/multiarch/strncat-c.c: New File.
	* sysdeps/s390/multiarch/strncat-vx.S: Likewise.
	* sysdeps/s390/multiarch/strncat.c: Likewise.
	* sysdeps/s390/multiarch/wcsncat-c.c: Likewise.
	* sysdeps/s390/multiarch/wcsncat-vx.S: Likewise.
	* sysdeps/s390/multiarch/wcsncat.c: Likewise.
	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strncat and
	wcsncat functions.
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Add ifunc test for strncat, wcsncat.
	* wcsmbs/wcsncat.c (WCSNCAT): Define and use macro.
	* string/test-strncat.c: Add wcsncat support.
	* wcsmbs/test-wcsncat.c: New File.
	* wcsmbs/Makefile (strop-tests): Add wcsncat.
	* benchtests/bench-strncat.c: Add wcsncat support.
	* benchtests/bench-wcsncat.c: New File.
	* benchtests/Makefile (wcsmbs-bench): Add wcsncat.

16 files changed, 826 insertions, 93 deletions

diff --git a/ChangeLog b/ChangeLog
index d87525fbe3..9d8948ad32 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,25 @@
 2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
+	* sysdeps/s390/multiarch/strncat-c.c: New File.
+	* sysdeps/s390/multiarch/strncat-vx.S: Likewise.
+	* sysdeps/s390/multiarch/strncat.c: Likewise.
+	* sysdeps/s390/multiarch/wcsncat-c.c: Likewise.
+	* sysdeps/s390/multiarch/wcsncat-vx.S: Likewise.
+	* sysdeps/s390/multiarch/wcsncat.c: Likewise.
+	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strncat and
+	wcsncat functions.
+	* sysdeps/s390/multiarch/ifunc-impl-list.c
+	(__libc_ifunc_impl_list): Add ifunc test for strncat, wcsncat.
+	* wcsmbs/wcsncat.c (WCSNCAT): Define and use macro.
+	* string/test-strncat.c: Add wcsncat support.
+	* wcsmbs/test-wcsncat.c: New File.
+	* wcsmbs/Makefile (strop-tests): Add wcsncat.
+	* benchtests/bench-strncat.c: Add wcsncat support.
+	* benchtests/bench-wcsncat.c: New File.
+	* benchtests/Makefile (wcsmbs-bench): Add wcsncat.
+
+2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
 	* sysdeps/s390/multiarch/strcat-c.c: New File.
 	* sysdeps/s390/multiarch/strcat-vx.S: Likewise.
 	* sysdeps/s390/multiarch/strcat.c: Likewise.
diff --git a/benchtests/Makefile b/benchtests/Makefile
index 7c724fbda6..44a0471cc2 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 wcsncpy wcpncpy wcscat
+wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy wcsncpy wcpncpy wcscat wcsncat
 string-bench-all := $(string-bench) ${wcsmbs-bench}
 
 # We have to generate locales
diff --git a/benchtests/bench-strncat.c b/benchtests/bench-strncat.c
index 85a313514f..8f3339dc78 100644
--- a/benchtests/bench-strncat.c
+++ b/benchtests/bench-strncat.c
@@ -17,33 +17,58 @@
    <http://www.gnu.org/licenses/>.  */
 
 #define TEST_MAIN
-#define TEST_NAME "strncat"
+#ifndef WIDE
+# define TEST_NAME "strncat"
+#else
+# define TEST_NAME "wcsncat"
+#endif /* WIDE */
 #include "bench-string.h"
 
-typedef char *(*proto_t) (char *, const char *, size_t);
-char *stupid_strncat (char *, const char *, size_t);
-char *simple_strncat (char *, const char *, size_t);
-
-IMPL (stupid_strncat, 0)
-IMPL (strncat, 2)
-
-char *
-stupid_strncat (char *dst, const char *src, size_t n)
+#ifndef WIDE
+# define STRNCAT strncat
+# define CHAR char
+# define SIMPLE_STRNCAT simple_strncat
+# define STUPID_STRNCAT stupid_strncat
+# define STRLEN strlen
+# define MEMCMP memcmp
+# define BIG_CHAR CHAR_MAX
+# define SMALL_CHAR 127
+#else
+# include <wchar.h>
+# define STRNCAT wcsncat
+# define CHAR wchar_t
+# define SIMPLE_STRNCAT simple_wcsncat
+# define STUPID_STRNCAT stupid_wcsncat
+# define STRLEN wcslen
+# define MEMCMP wmemcmp
+# define BIG_CHAR WCHAR_MAX
+# define SMALL_CHAR 1273
+#endif /* WIDE */
+
+typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
+CHAR *STUPID_STRNCAT (CHAR *, const CHAR *, size_t);
+CHAR *SIMPLE_STRNCAT (CHAR *, const CHAR *, size_t);
+
+IMPL (STUPID_STRNCAT, 0)
+IMPL (STRNCAT, 2)
+
+CHAR *
+STUPID_STRNCAT (CHAR *dst, const CHAR *src, size_t n)
 {
-  char *ret = dst;
+  CHAR *ret = dst;
   while (*dst++ != '\0');
   --dst;
   while (n--)
-    if ( (*dst++ = *src++) == '\0')
+    if ((*dst++ = *src++) == '\0')
       return ret;
   *dst = '\0';
   return ret;
 }
 
 static void
-do_one_test (impl_t *impl, char *dst, const char *src, size_t n)
+do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t n)
 {
-  size_t k = strlen (dst), i, iters = INNER_LOOP_ITERS;
+  size_t k = STRLEN (dst), i, iters = INNER_LOOP_ITERS;
   timing_t start, stop, cur;
 
   if (CALL (impl, dst, src, n) != dst)
@@ -54,10 +79,10 @@ do_one_test (impl_t *impl, char *dst, const char *src, size_t n)
       return;
     }
 
-  size_t len = strlen (src);
-  if (memcmp (dst + k, src, len + 1 > n ? n : len + 1) != 0)
+  size_t len = STRLEN (src);
+  if (MEMCMP (dst + k, src, len + 1 > n ? n : len + 1) != 0)
     {
-      error (0, 0, "Incorrect cancatination in function %s",
+      error (0, 0, "Incorrect concatenation in function %s",
 	     impl->name);
       ret = 1;
       return;
@@ -88,20 +113,20 @@ do_test (size_t align1, size_t align2, size_t len1, size_t len2,
 	 size_t n, int max_char)
 {
   size_t i;
-  char *s1, *s2;
+  CHAR *s1, *s2;
 
   align1 &= 7;
-  if (align1 + len1 >= page_size)
+  if ((align1 + len1) * sizeof (CHAR) >= page_size)
     return;
-  if (align1 + n > page_size)
+  if ((align1 + n) * sizeof (CHAR) > page_size)
     return;
   align2 &= 7;
-  if (align2 + len1 + len2 >= page_size)
+  if ((align2 + len1 + len2) * sizeof (CHAR) >= page_size)
     return;
-  if (align2 + len1 + n > page_size)
+  if ((align2 + len1 + n) * 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 < len1; ++i)
     s1[i] = 32 + 23 * i % (max_char - 32);
@@ -136,25 +161,25 @@ main (void)
 
   for (n = 2; n <= 2048; n*=4)
     {
-      do_test (0, 2, 2, 2, n, 127);
-      do_test (0, 0, 4, 4, n, 127);
-      do_test (4, 0, 4, 4, n, 255);
-      do_test (0, 0, 8, 8, n, 127);
-      do_test (0, 8, 8, 8, n, 127);
+      do_test (0, 2, 2, 2, n, SMALL_CHAR);
+      do_test (0, 0, 4, 4, n, SMALL_CHAR);
+      do_test (4, 0, 4, 4, n, BIG_CHAR);
+      do_test (0, 0, 8, 8, n, SMALL_CHAR);
+      do_test (0, 8, 8, 8, n, SMALL_CHAR);
 
       for (i = 1; i < 8; ++i)
 	{
-	  do_test (0, 0, 8 << i, 8 << i, n, 127);
-	  do_test (8 - i, 2 * i, 8 << i, 8 << i, n, 127);
-	  do_test (0, 0, 8 << i, 2 << i, n, 127);
-	  do_test (8 - i, 2 * i, 8 << i, 2 << i, n, 127);
+	  do_test (0, 0, 8 << i, 8 << i, n, SMALL_CHAR);
+	  do_test (8 - i, 2 * i, 8 << i, 8 << i, n, SMALL_CHAR);
+	  do_test (0, 0, 8 << i, 2 << i, n, SMALL_CHAR);
+	  do_test (8 - i, 2 * i, 8 << i, 2 << i, n, SMALL_CHAR);
 	}
 
       for (i = 1; i < 8; ++i)
 	{
-	  do_test (i, 2 * i, 8 << i, 1, n, 127);
-	  do_test (2 * i, i, 8 << i, 1, n, 255);
-	  do_test (i, i, 8 << i, 10, n, 127);
+	  do_test (i, 2 * i, 8 << i, 1, n, SMALL_CHAR);
+	  do_test (2 * i, i, 8 << i, 1, n, BIG_CHAR);
+	  do_test (i, i, 8 << i, 10, n, SMALL_CHAR);
 	}
     }
 
diff --git a/benchtests/bench-wcsncat.c b/benchtests/bench-wcsncat.c
new file mode 100644
index 0000000000..b9d7c3f323
--- /dev/null
+++ b/benchtests/bench-wcsncat.c
@@ -0,0 +1,20 @@
+/* Measure wcsncat 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-strncat.c"
diff --git a/string/test-strncat.c b/string/test-strncat.c
index 366e6fccb5..3571568b93 100644
--- a/string/test-strncat.c
+++ b/string/test-strncat.c
@@ -1,4 +1,4 @@
-/* Test and measure strncat functions.
+/* Test strncat functions.
    Copyright (C) 2011-2015 Free Software Foundation, Inc.
    Contributed by Intel Corporation.
 
@@ -17,33 +17,64 @@
    <http://www.gnu.org/licenses/>.  */
 
 #define TEST_MAIN
-#define TEST_NAME "strncat"
+#ifndef WIDE
+# define TEST_NAME "strncat"
+#else
+# define TEST_NAME "wcsncat"
+#endif /* WIDE */
 #include "test-string.h"
 
-typedef char *(*proto_t) (char *, const char *, size_t);
-char *stupid_strncat (char *, const char *, size_t);
-char *simple_strncat (char *, const char *, size_t);
+#ifndef WIDE
+# define STRNCAT strncat
+# define CHAR char
+# define UCHAR unsigned char
+# define SIMPLE_STRNCAT simple_strncat
+# define STUPID_STRNCAT stupid_strncat
+# define STRLEN strlen
+# define MEMSET memset
+# define MEMCPY memcpy
+# define MEMCMP memcmp
+# define BIG_CHAR CHAR_MAX
+# define SMALL_CHAR 127
+#else
+# include <wchar.h>
+# define STRNCAT wcsncat
+# define CHAR wchar_t
+# define UCHAR wchar_t
+# define SIMPLE_STRNCAT simple_wcsncat
+# define STUPID_STRNCAT stupid_wcsncat
+# define STRLEN wcslen
+# define MEMSET wmemset
+# define MEMCPY wmemcpy
+# define MEMCMP wmemcmp
+# define BIG_CHAR WCHAR_MAX
+# define SMALL_CHAR 1273
+#endif /* WIDE */
 
-IMPL (stupid_strncat, 0)
-IMPL (strncat, 2)
+typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
+CHAR *STUPID_STRNCAT (CHAR *, const CHAR *, size_t);
+CHAR *SIMPLE_STRNCAT (CHAR *, const CHAR *, size_t);
 
-char *
-stupid_strncat (char *dst, const char *src, size_t n)
+IMPL (STUPID_STRNCAT, 0)
+IMPL (STRNCAT, 2)
+
+CHAR *
+STUPID_STRNCAT (CHAR *dst, const CHAR *src, size_t n)
 {
-  char *ret = dst;
+  CHAR *ret = dst;
   while (*dst++ != '\0');
   --dst;
   while (n--)
-    if ( (*dst++ = *src++) == '\0')
+    if ((*dst++ = *src++) == '\0')
       return ret;
   *dst = '\0';
   return ret;
 }
 
 static void
-do_one_test (impl_t *impl, char *dst, const char *src, size_t n)
+do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t n)
 {
-  size_t k = strlen (dst);
+  size_t k = STRLEN (dst);
   if (CALL (impl, dst, src, n) != dst)
     {
       error (0, 0, "Wrong result in function %s %p != %p", impl->name,
@@ -52,10 +83,10 @@ do_one_test (impl_t *impl, char *dst, const char *src, size_t n)
       return;
     }
 
-  size_t len = strlen (src);
-  if (memcmp (dst + k, src, len + 1 > n ? n : len + 1) != 0)
+  size_t len = STRLEN (src);
+  if (MEMCMP (dst + k, src, len + 1 > n ? n : len + 1) != 0)
     {
-      error (0, 0, "Incorrect cancatination in function %s",
+      error (0, 0, "Incorrect concatenation in function %s",
 	     impl->name);
       ret = 1;
       return;
@@ -74,20 +105,20 @@ do_test (size_t align1, size_t align2, size_t len1, size_t len2,
 	 size_t n, int max_char)
 {
   size_t i;
-  char *s1, *s2;
+  CHAR *s1, *s2;
 
   align1 &= 7;
-  if (align1 + len1 >= page_size)
+  if ((align1 + len1) * sizeof (CHAR) >= page_size)
     return;
-  if (align1 + n > page_size)
+  if ((align1 + n) * sizeof (CHAR) > page_size)
     return;
   align2 &= 7;
-  if (align2 + len1 + len2 >= page_size)
+  if ((align2 + len1 + len2) * sizeof (CHAR) >= page_size)
     return;
-  if (align2 + len1 + n > page_size)
+  if ((align2 + len1 + n) * 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 < len1; ++i)
     s1[i] = 32 + 23 * i % (max_char - 32);
@@ -107,9 +138,10 @@ static void
 do_random_tests (void)
 {
   size_t i, j, n, align1, align2, len1, len2, N;
-  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 *p3 = (UCHAR *) buf1;
+  UCHAR *res;
   fprintf (stdout, "Number of iterations in random test = %zd\n",
 	   ITERATIONS);
   for (n = 0; n < ITERATIONS; n++)
@@ -148,26 +180,26 @@ do_random_tests (void)
 	    p1[i] = 0;
 	  else
 	    {
-	      p1[i] = random () & 255;
+	      p1[i] = random () & BIG_CHAR;
 	      if (i >= align1 && i < len1 + align1 && !p1[i])
-		p1[i] = (random () & 127) + 3;
+		p1[i] = (random () & SMALL_CHAR) + 3;
 	    }
 	}
       for (i = 0; i < len2; i++)
 	{
-	  buf1[i] = random () & 255;
-	  if (!buf1[i])
-	    buf1[i] = (random () & 127) + 3;
+	  p3[i] = random () & BIG_CHAR;
+	  if (!p3[i])
+	    p3[i] = (random () & SMALL_CHAR) + 3;
 	}
-      buf1[len2] = 0;
+      p3[len2] = 0;
 
       FOR_EACH_IMPL (impl, 1)
 	{
-	  memset (p2 - 64, '\1', align2 + 64);
-	  memset (p2 + align2 + len2 + 1, '\1', 512 - align2 - len2 - 1);
-	  memcpy (p2 + align2, buf1, len2 + 1);
-	  res = (unsigned char *) CALL (impl, (char *) (p2 + align2),
-					(char *) (p1 + align1), N);
+	  MEMSET (p2 - 64, '\1', align2 + 64);
+	  MEMSET (p2 + align2 + len2 + 1, '\1', 512 - align2 - len2 - 1);
+	  MEMCPY (p2 + align2, p3, len2 + 1);
+	  res = (UCHAR *) CALL (impl, (CHAR *) (p2 + align2),
+				(CHAR *) (p1 + align1), N);
 	  if (res != p2 + align2)
 	    {
 	      error (0, 0, "Iteration %zd - wrong result in function %s "
@@ -187,7 +219,7 @@ do_random_tests (void)
 		  break;
 		}
 	    }
-	  if (memcmp (p2 + align2, buf1, len2))
+	  if (MEMCMP (p2 + align2, p3, len2))
 	    {
 	      error (0, 0, "Iteration %zd - garbage in string before, %s "
 		     "(%zd, %zd, %zd, %zd, %zd)",
@@ -220,7 +252,7 @@ do_random_tests (void)
 		  ret = 1;
 		}
 	    }
-	  if (memcmp (p1 + align1, p2 + align2 + len2,
+	  if (MEMCMP (p1 + align1, p2 + align2 + len2,
 		      (len1 + 1) > N ? N : len1 + 1))
 	    {
 	      error (0, 0, "Iteration %zd - different strings, %s "
@@ -233,7 +265,7 @@ do_random_tests (void)
 }
 
 int
-main (void)
+test_main (void)
 {
   size_t i, n;
 
@@ -246,28 +278,30 @@ main (void)
 
   for (n = 2; n <= 2048; n*=4)
     {
-      do_test (0, 2, 2, 2, n, 127);
-      do_test (0, 0, 4, 4, n, 127);
-      do_test (4, 0, 4, 4, n, 255);
-      do_test (0, 0, 8, 8, n, 127);
-      do_test (0, 8, 8, 8, n, 127);
+      do_test (0, 2, 2, 2, n, SMALL_CHAR);
+      do_test (0, 0, 4, 4, n, SMALL_CHAR);
+      do_test (4, 0, 4, 4, n, BIG_CHAR);
+      do_test (0, 0, 8, 8, n, SMALL_CHAR);
+      do_test (0, 8, 8, 8, n, SMALL_CHAR);
 
       for (i = 1; i < 8; ++i)
 	{
-	  do_test (0, 0, 8 << i, 8 << i, n, 127);
-	  do_test (8 - i, 2 * i, 8 << i, 8 << i, n, 127);
-	  do_test (0, 0, 8 << i, 2 << i, n, 127);
-	  do_test (8 - i, 2 * i, 8 << i, 2 << i, n, 127);
+	  do_test (0, 0, 8 << i, 8 << i, n, SMALL_CHAR);
+	  do_test (8 - i, 2 * i, 8 << i, 8 << i, n, SMALL_CHAR);
+	  do_test (0, 0, 8 << i, 2 << i, n, SMALL_CHAR);
+	  do_test (8 - i, 2 * i, 8 << i, 2 << i, n, SMALL_CHAR);
 	}
 
       for (i = 1; i < 8; ++i)
 	{
-	  do_test (i, 2 * i, 8 << i, 1, n, 127);
-	  do_test (2 * i, i, 8 << i, 1, n, 255);
-	  do_test (i, i, 8 << i, 10, n, 127);
+	  do_test (i, 2 * i, 8 << i, 1, n, SMALL_CHAR);
+	  do_test (2 * i, i, 8 << i, 1, n, BIG_CHAR);
+	  do_test (i, i, 8 << i, 10, n, SMALL_CHAR);
 	}
     }
 
   do_random_tests ();
   return ret;
 }
+
+#include "../test-skeleton.c"
diff --git a/sysdeps/s390/multiarch/Makefile b/sysdeps/s390/multiarch/Makefile
index 6283999faa..33c139820a 100644
--- a/sysdeps/s390/multiarch/Makefile
+++ b/sysdeps/s390/multiarch/Makefile
@@ -5,7 +5,8 @@ sysdep_routines += strlen strlen-vx strlen-c \
 		   stpcpy stpcpy-vx stpcpy-c \
 		   strncpy strncpy-vx \
 		   stpncpy stpncpy-vx stpncpy-c \
-		   strcat strcat-vx strcat-c
+		   strcat strcat-vx strcat-c \
+		   strncat strncat-vx strncat-c
 endif
 
 ifeq ($(subdir),wcsmbs)
@@ -15,5 +16,6 @@ sysdep_routines += wcslen wcslen-vx wcslen-c \
 		   wcpcpy wcpcpy-vx wcpcpy-c \
 		   wcsncpy wcsncpy-vx wcsncpy-c \
 		   wcpncpy wcpncpy-vx wcpncpy-c \
-		   wcscat wcscat-vx wcscat-c
+		   wcscat wcscat-vx wcscat-c \
+		   wcsncat wcsncat-vx wcsncat-c
 endif
diff --git a/sysdeps/s390/multiarch/ifunc-impl-list.c b/sysdeps/s390/multiarch/ifunc-impl-list.c
index ccf4dea198..1e57c0eb04 100644
--- a/sysdeps/s390/multiarch/ifunc-impl-list.c
+++ b/sysdeps/s390/multiarch/ifunc-impl-list.c
@@ -100,6 +100,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
   IFUNC_VX_IMPL (strcat);
   IFUNC_VX_IMPL (wcscat);
 
+  IFUNC_VX_IMPL (strncat);
+  IFUNC_VX_IMPL (wcsncat);
+
 #endif /* HAVE_S390_VX_ASM_SUPPORT */
 
   return i;
diff --git a/sysdeps/s390/multiarch/strncat-c.c b/sysdeps/s390/multiarch/strncat-c.c
new file mode 100644
index 0000000000..ac3a057dcb
--- /dev/null
+++ b/sysdeps/s390/multiarch/strncat-c.c
@@ -0,0 +1,23 @@
+/* Default strncat 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 STRNCAT  __strncat_c
+
+# include <string/strncat.c>
+#endif
diff --git a/sysdeps/s390/multiarch/strncat-vx.S b/sysdeps/s390/multiarch/strncat-vx.S
new file mode 100644
index 0000000000..4435d9f8d2
--- /dev/null
+++ b/sysdeps/s390/multiarch/strncat-vx.S
@@ -0,0 +1,239 @@
+/* Vector optimized 32/64 bit S/390 version of strncat.
+   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"