S390: Optimize strchrnul and wcschrnul.

This patch provides optimized versions of strchrnul and wcschrnul with the z13
vector instructions.

ChangeLog:

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

16 files changed, 406 insertions, 19 deletions

diff --git a/ChangeLog b/ChangeLog
index 04e8552..3903d1f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,25 @@
 2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
+	* sysdeps/s390/multiarch/strchrnul-c.c: New File.
+	* sysdeps/s390/multiarch/strchrnul-vx.S: Likewise.
+	* sysdeps/s390/multiarch/strchrnul.c: Likewise.
+	* sysdeps/s390/multiarch/wcschrnul-c.c: Likewise.
+	* sysdeps/s390/multiarch/wcschrnul-vx.S: Likewise.
+	* sysdeps/s390/multiarch/wcschrnul.c: Likewise.
+	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strchrnul and
+	wcschrnul functions.
+	* sysdeps/s390/multiarch/ifunc-impl-list.c
+	(__libc_ifunc_impl_list): Add ifunc test for strchrnul, wcschrnul.
+	* wcsmbs/wcschrnul.c: Use WCSCHRNUL if defined.
+	* string/test-strchr.c: Add wcschrnul support.
+	* wcsmbs/test-wcschrnul.c: New File.
+	* wcsmbs/Makefile (strop-tests): Add wcschrnul.
+	* benchtests/bench-strchr.c: Add wcschrnul support.
+	* benchtests/bench-wcschrnul.c: New File.
+	* benchtests/Makefile (wcsmbs-bench): Add wcschrnul.
+
+2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
 	* sysdeps/s390/multiarch/strchr-c.c: New File.
 	* sysdeps/s390/multiarch/strchr-vx.S: Likewise.
 	* sysdeps/s390/multiarch/strchr.c: Likewise.
diff --git a/benchtests/Makefile b/benchtests/Makefile
index b931f60..b3298d4 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -37,7 +37,7 @@ string-bench := bcopy bzero memccpy memchr memcmp memcpy memmem memmove \
 		strspn strstr strcpy_chk stpcpy_chk memrchr strsep strtok \
 		strcoll
 wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy wcsncpy wcpncpy wcscat wcsncat \
-		wcscmp wcsncmp wcschr
+		wcscmp wcsncmp wcschr wcschrnul
 string-bench-all := $(string-bench) ${wcsmbs-bench}
 
 # We have to generate locales
diff --git a/benchtests/bench-strchr.c b/benchtests/bench-strchr.c
index 89e177a..e4e2775 100644
--- a/benchtests/bench-strchr.c
+++ b/benchtests/bench-strchr.c
@@ -22,10 +22,14 @@
 #  define TEST_NAME "strchrnul"
 # else
 #  define TEST_NAME "strchr"
-# endif
+# endif /* !USE_FOR_STRCHRNUL */
 #else
-# define TEST_NAME "wcschr"
-#endif
+# ifdef USE_FOR_STRCHRNUL
+#  define TEST_NAME "wcschrnul"
+# else
+#  define TEST_NAME "wcschr"
+# endif /* !USE_FOR_STRCHRNUL */
+#endif /* WIDE */
 #include "bench-string.h"
 
 #ifndef WIDE
@@ -35,7 +39,7 @@
 #  define simple_STRCHR simple_STRCHRNUL
 # else
 #  define STRCHR strchr
-# endif
+# endif /* !USE_FOR_STRCHRNUL */
 # define STRLEN strlen
 # define CHAR char
 # define BIG_CHAR CHAR_MAX
@@ -44,20 +48,26 @@
 # define UCHAR unsigned char
 #else
 # include <wchar.h>
-# define STRCHR wcschr
+# ifdef USE_FOR_STRCHRNUL
+#  define STRCHR wcschrnul
+#  define stupid_STRCHR stupid_WCSCHRNUL
+#  define simple_STRCHR simple_WCSCHRNUL
+# else
+#  define STRCHR wcschr
+# endif /* !USE_FOR_STRCHRNUL */
 # define STRLEN wcslen
 # define CHAR wchar_t
 # define BIG_CHAR WCHAR_MAX
 # define MIDDLE_CHAR 1121
 # define SMALL_CHAR 851
 # define UCHAR wchar_t
-#endif
+#endif /* WIDE */
 
 #ifdef USE_FOR_STRCHRNUL
 # define NULLRET(endptr) endptr
 #else
 # define NULLRET(endptr) NULL
-#endif
+#endif /* !USE_FOR_STRCHRNUL */
 
 
 typedef CHAR *(*proto_t) (const CHAR *, int);
diff --git a/benchtests/bench-wcschrnul.c b/benchtests/bench-wcschrnul.c
new file mode 100644
index 0000000..124b602
--- /dev/null
+++ b/benchtests/bench-wcschrnul.c
@@ -0,0 +1,20 @@
+/* Measure wcschrnul 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-strchrnul.c"
diff --git a/string/test-strchr.c b/string/test-strchr.c
index ea06c43..b3a7ba4 100644
--- a/string/test-strchr.c
+++ b/string/test-strchr.c
@@ -1,4 +1,4 @@
-/* Test and measure STRCHR functions.
+/* Test STRCHR 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.
@@ -24,10 +24,14 @@
 #  define TEST_NAME "strchrnul"
 # else
 #  define TEST_NAME "strchr"
-# endif
+# endif /* !USE_FOR_STRCHRNUL */
 #else
-# define TEST_NAME "wcschr"
-#endif
+# ifdef USE_FOR_STRCHRNUL
+#  define TEST_NAME "wcschrnul"
+# else
+#  define TEST_NAME "wcschr"
+# endif /* !USE_FOR_STRCHRNUL */
+#endif /* WIDE */
 #include "test-string.h"
 
 #ifndef WIDE
@@ -37,7 +41,7 @@
 #  define simple_STRCHR simple_STRCHRNUL
 # else
 #  define STRCHR strchr
-# endif
+# endif /* !USE_FOR_STRCHRNUL */
 # define STRLEN strlen
 # define CHAR char
 # define BIG_CHAR CHAR_MAX
@@ -47,7 +51,13 @@
 # define L(s) s
 #else
 # include <wchar.h>
-# define STRCHR wcschr
+# ifdef USE_FOR_STRCHRNUL
+#  define STRCHR wcschrnul
+#  define stupid_STRCHR stupid_WCSCHRNUL
+#  define simple_STRCHR simple_WCSCHRNUL
+# else
+#  define STRCHR wcschr
+# endif /* !USE_FOR_STRCHRNUL */
 # define STRLEN wcslen
 # define CHAR wchar_t
 # define BIG_CHAR WCHAR_MAX
@@ -55,13 +65,13 @@
 # define SMALL_CHAR 851
 # define UCHAR wchar_t
 # define L(s) L ## s
-#endif
+#endif /* WIDE */
 
 #ifdef USE_FOR_STRCHRNUL
 # define NULLRET(endptr) endptr
 #else
 # define NULLRET(endptr) NULL
-#endif
+#endif /* !USE_FOR_STRCHRNUL */
 
 
 typedef CHAR *(*proto_t) (const CHAR *, int);
diff --git a/sysdeps/s390/multiarch/Makefile b/sysdeps/s390/multiarch/Makefile
index 1a3673b..b6b64c9 100644
--- a/sysdeps/s390/multiarch/Makefile
+++ b/sysdeps/s390/multiarch/Makefile
@@ -9,7 +9,8 @@ sysdep_routines += strlen strlen-vx strlen-c \
 		   strncat strncat-vx strncat-c \
 		   strcmp strcmp-vx \
 		   strncmp strncmp-vx strncmp-c \
-		   strchr strchr-vx strchr-c
+		   strchr strchr-vx strchr-c \
+		   strchrnul strchrnul-vx strchrnul-c
 endif
 
 ifeq ($(subdir),wcsmbs)
@@ -23,5 +24,6 @@ sysdep_routines += wcslen wcslen-vx wcslen-c \
 		   wcsncat wcsncat-vx wcsncat-c \
 		   wcscmp wcscmp-vx wcscmp-c \
 		   wcsncmp wcsncmp-vx wcsncmp-c \
-		   wcschr wcschr-vx wcschr-c
+		   wcschr wcschr-vx wcschr-c \
+		   wcschrnul wcschrnul-vx wcschrnul-c
 endif
diff --git a/sysdeps/s390/multiarch/ifunc-impl-list.c b/sysdeps/s390/multiarch/ifunc-impl-list.c
index b0782ff..ea474a8 100644
--- a/sysdeps/s390/multiarch/ifunc-impl-list.c
+++ b/sysdeps/s390/multiarch/ifunc-impl-list.c
@@ -112,6 +112,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
   IFUNC_VX_IMPL (strchr);
   IFUNC_VX_IMPL (wcschr);
 
+  IFUNC_VX_IMPL (strchrnul);
+  IFUNC_VX_IMPL (wcschrnul);
+
 #endif /* HAVE_S390_VX_ASM_SUPPORT */
 
   return i;
diff --git a/sysdeps/s390/multiarch/strchrnul-c.c b/sysdeps/s390/multiarch/strchrnul-c.c
new file mode 100644
index 0000000..1f288e4
--- /dev/null
+++ b/sysdeps/s390/multiarch/strchrnul-c.c
@@ -0,0 +1,26 @@
+/* Default strchrnul 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 STRCHRNUL  __strchrnul_c
+# define __strchrnul STRCHRNUL
+# undef weak_alias
+# define weak_alias(name, alias)
+
+# include <string/strchrnul.c>
+#endif
diff --git a/sysdeps/s390/multiarch/strchrnul-vx.S b/sysdeps/s390/multiarch/strchrnul-vx.S
new file mode 100644
index 0000000..5b43a93
--- /dev/null
+++ b/sysdeps/s390/multiarch/strchrnul-vx.S
@@ -0,0 +1,93 @@
+/* Vector optimized 32/64 bit S/390 version of strchrnul.
+   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 *strchrnul (const char *s, int c)
+   Returns pointer to first c or to \0 if c not found.
+
+   Register usage:
+   -r1=tmp
+   -r2=s and return pointer
+   -r3=c
+   -r4=tmp
+   -r5=current_len
+   -v16=part of s
+   -v18=vector with c replicated in every byte
+*/
+ENTRY(__strchrnul_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+	vlbb	%v16,0(%r2),6	/* Load s until next 4k-byte boundary.  */
+	lcbb	%r1,0(%r2),6	/* Get bytes to 4k-byte boundary or 16.  */
+
+	lghi	%r5,0		/* current_len = 0.  */
+
+	vlvgb	%v18,%r3,0	/* Generate vector which elements are all c.
+				   If c > 255, c will be truncated.  */
+	vrepb	%v18,%v18,0
+
+	vfeezbs	%v16,%v16,%v18	/* Find element equal with zero search.  */
+	vlgvb	%r4,%v16,7	/* Load byte index of character or zero.  */
+	clrjl	%r4,%r1,.Lfound /* Return if c/zero is in loaded bytes.  */
+
+	/* Align s to 16 byte.  */
+	risbgn	%r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
+	lghi	%r5,16		/* current_len = 16.  */
+	slr	%r5,%r4		/* Compute bytes to 16bytes boundary.  */
+
+	/* Find c/zero in 16byte aligned loop */
+.Lloop:
+	vl	%v16,0(%r5,%r2) /* Load s */
+	vfeezbs	%v16,%v16,%v18	/* Find element equal with zero search.  */
+	jno	.Lfound		/* Found c/zero (cc=0|1|2).  */
+	vl	%v16,16(%r5,%r2)
+	vfeezbs	%v16,%v16,%v18
+	jno	.Lfound16
+	vl	%v16,32(%r5,%r2)
+	vfeezbs	%v16,%v16,%v18
+	jno	.Lfound32
+	vl	%v16,48(%r5,%r2)
+	vfeezbs	%v16,%v16,%v18
+	jno	.Lfound48
+
+	aghi	%r5,64
+	j	.Lloop		/* No character and no zero -> loop.  */
+
+	/* Found character or zero */
+.Lfound48:
+	aghi	%r5,16
+.Lfound32:
+	aghi	%r5,16
+.Lfound16:
+	aghi	%r5,16
+.Lfound:
+	vlgvb	%r1,%v16,7	/* Load byte index of character.  */
+	algr	%r5,%r1
+	la	%r2,0(%r5,%r2)	/* Return pointer to character.  */
+
+.Lend:
+	br	%r14
+END(__strchrnul_vx)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
diff --git a/sysdeps/s390/multiarch/strchrnul.c b/sysdeps/s390/multiarch/strchrnul.c
new file mode 100644
index 0000000..652d517
--- /dev/null
+++ b/sysdeps/s390/multiarch/strchrnul.c
@@ -0,0 +1,28 @@
+/* Multiple versions of strchrnul.
+   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_ifunc (__strchrnul)
+weak_alias (__strchrnul, strchrnul)
+
+#else
+# include <string/strchrnul.c>
+#endif /* !(defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)) */
diff --git a/sysdeps/s390/multiarch/wcschrnul-c.c b/sysdeps/s390/multiarch/wcschrnul-c.c
new file mode 100644
index 0000000..10c7ab6
--- /dev/null
+++ b/sysdeps/s390/multiarch/wcschrnul-c.c
@@ -0,0 +1,25 @@
+/* Default wcschrnul 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 WCSCHRNUL  __wcschrnul_c
+
+# include <wchar.h>
+extern __typeof (__wcschrnul) __wcschrnul_c;
+# include <wcsmbs/wcschrnul.c>
+#endif
diff --git a/sysdeps/s390/multiarch/wcschrnul-vx.S b/sysdeps/s390/multiarch/wcschrnul-vx.S
new file mode 100644
index 0000000..f69064f
--- /dev/null
+++ b/sysdeps/s390/multiarch/wcschrnul-vx.S
@@ -0,0 +1,97 @@
+/* Vector optimized 32/64 bit S/390 version of wcschrnul.
+   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* wcschrnul (const wchar_t *s, wchar_t c)
+   Returns pointer to first c or to \0 if c not found.
+
+   Register usage:
+   -r1=tmp
+   -r2=s and return pointer
+   -r3=c
+   -r4=tmp
+   -r5=current_len
+   -v16=part of s
+   -v18=vector with c replicated in every byte
+*/
+ENTRY(__wcschrnul_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+	vlbb	%v16,0(%r2),6	/* Load s until next 4k-byte boundary.  */
+	lcbb	%r1,0(%r2),6	/* Get bytes to 4k-byte boundary or 16.  */
+
+	tmll	%r2,3		/* Test if s is 4-byte aligned?   */
+	jne	.Lfallback	/* And use common-code variant if not.  */
+
+	lghi	%r5,0		/* current_len = 0.  */
+
+	vlvgf	%v18,%r3,0	/* Generate vector which elements are all c.  */
+	vrepf	%v18,%v18,0
+
+	vfeezfs	%v16,%v16,%v18	/* Find element equal with zero search.  */
+	vlgvb	%r4,%v16,7	/* Load byte index of character or zero.  */
+	clrjl	%r4,%r1,.Lfound /* Return if c/zero is in loaded bytes.  */
+
+	/* Align s to 16 byte.  */
+	risbgn	%r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
+	lghi	%r5,16		/* current_len = 16.  */
+	slr	%r5,%r4		/* Compute bytes to 16bytes boundary.  */
+
+	/* Find c/zero in 16byte aligned loop */
+.Lloop:
+	vl	%v16,0(%r5,%r2) /* Load s.  */
+	vfeezfs	%v16,%v16,%v18	/* Find element equal with zero search.  */
+	jno	.Lfound		/* Found c/zero (cc=0|1|2).  */
+	vl	%v16,16(%r5,%r2)
+	vfeezfs	%v16,%v16,%v18
+	jno	.Lfound16
+	vl	%v16,32(%r5,%r2)
+	vfeezfs	%v16,%v16,%v18
+	jno	.Lfound32
+	vl	%v16,48(%r5,%r2)
+	vfeezfs	%v16,%v16,%v18
+	jno	.Lfound48
+
+	aghi	%r5,64
+	j	.Lloop		/* No character and no zero -> loop.  */
+
+	/* Found character or zero */
+.Lfound48:
+	aghi	%r5,16
+.Lfound32:
+	aghi	%r5,16
+.Lfound16:
+	aghi	%r5,16
+.Lfound:
+	vlgvb	%r1,%v16,7	/* Load byte index of character.  */
+	algr	%r5,%r1
+	la	%r2,0(%r5,%r2)	/* Return pointer to character.  */
+
+.Lend:
+	br	%r14
+.Lfallback:
+	jg	__wcschrnul_c
+END(__wcschrnul_vx)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
diff --git a/sysdeps/s390/multiarch/wcschrnul.c b/sysdeps/s390/multiarch/wcschrnul.c
new file mode 100644
index 0000000..0f91e26
--- /dev/null
+++ b/sysdeps/s390/multiarch/wcschrnul.c
@@ -0,0 +1,28 @@
+/* Multiple versions of wcschrnul.
+   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 (__wcschrnul)
+weak_alias (__wcschrnul, wcschrnul)
+
+#else
+# include <wcsmbs/wcschrnul.c>
+#endif /* !(defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)) */
diff --git a/wcsmbs/Makefile b/wcsmbs/Makefile
index 3b6c472..a4c7077 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 wcsncpy wcpncpy wcscat wcsncat
+		wcpcpy wcsncpy wcpncpy wcscat wcsncat wcschrnul
 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-wcschrnul.c b/wcsmbs/test-wcschrnul.c
new file mode 100644
index 0000000..baea763
--- /dev/null
+++ b/wcsmbs/test-wcschrnul.c
@@ -0,0 +1,20 @@
+/* Test wcschrnul 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-strchrnul.c"
diff --git a/wcsmbs/wcschrnul.c b/wcsmbs/wcschrnul.c
index 4bc42d1..97ef3b9 100644
--- a/wcsmbs/wcschrnul.c
+++ b/wcsmbs/wcschrnul.c
@@ -17,6 +17,9 @@
 
 #include <wchar.h>
 
+#ifdef WCSCHRNUL
+# define __wcschrnul WCSCHRNUL
+#endif
 
 /* Find the first occurrence of WC in WCS.  */
 wchar_t *
@@ -32,4 +35,6 @@ __wcschrnul (wcs, wc)
 
   return (wchar_t *) wcs;
 }
+#ifndef WCSCHRNUL
 weak_alias (__wcschrnul, wcschrnul)
+#endif