S390: Refactor strnlen ifunc handling.

The ifunc handling for strnlen is adjusted in order to omit ifunc
variants if those will never be used as the minimum architecture level
already supports newer CPUs by default.
Glibc internal calls will then also use the "newer" ifunc variant.

ChangeLog:

	* sysdeps/s390/multiarch/Makefile
	(sysdep_routines): Remove strnlen variants.
	* sysdeps/s390/Makefile (sysdep_routines): Add strnlen variants.
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Refactor ifunc handling for strnlen.
	* sysdeps/s390/multiarch/strnlen-c.c: Move to ...
	* sysdeps/s390/strnlen-c.c: ... here and adjust ifunc handling.
	* sysdeps/s390/multiarch/strnlen-vx.S: Move to ...
	* sysdeps/s390/strnlen-vx.S: ... here and adjust ifunc handling.
	* sysdeps/s390/multiarch/strnlen.c: Move to ...
	* sysdeps/s390/strnlen.c: ... here and adjust ifunc handling.
	* sysdeps/s390/ifunc-strnlen.h: New file.

5 files changed, 14 insertions, 199 deletions

diff --git a/sysdeps/s390/multiarch/Makefile b/sysdeps/s390/multiarch/Makefile
index 601523919c..35ba223c5d 100644
--- a/sysdeps/s390/multiarch/Makefile
+++ b/sysdeps/s390/multiarch/Makefile
@@ -1,6 +1,5 @@
 ifeq ($(subdir),string)
-sysdep_routines += strnlen strnlen-vx strnlen-c \
-		   strcpy strcpy-vx \
+sysdep_routines += strcpy strcpy-vx \
 		   stpcpy stpcpy-vx stpcpy-c \
 		   strncpy strncpy-vx \
 		   stpncpy stpncpy-vx stpncpy-c \
diff --git a/sysdeps/s390/multiarch/ifunc-impl-list.c b/sysdeps/s390/multiarch/ifunc-impl-list.c
index c531be4bc7..680e5b738b 100644
--- a/sysdeps/s390/multiarch/ifunc-impl-list.c
+++ b/sysdeps/s390/multiarch/ifunc-impl-list.c
@@ -27,6 +27,7 @@
 #include <ifunc-strstr.h>
 #include <ifunc-memmem.h>
 #include <ifunc-strlen.h>
+#include <ifunc-strnlen.h>
 
 /* Maximum number of IFUNC implementations.  */
 #define MAX_IFUNC	3
@@ -177,6 +178,18 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 		)
 #endif /* HAVE_STRLEN_IFUNC  */
 
+#if HAVE_STRNLEN_IFUNC
+    IFUNC_IMPL (i, name, strnlen,
+# if HAVE_STRNLEN_Z13
+		IFUNC_IMPL_ADD (array, i, strnlen,
+				dl_hwcap & HWCAP_S390_VX, STRNLEN_Z13)
+# endif
+# if HAVE_STRNLEN_C
+		IFUNC_IMPL_ADD (array, i, strnlen, 1, STRNLEN_C)
+# endif
+		)
+#endif /* HAVE_STRNLEN_IFUNC  */
+
 #ifdef HAVE_S390_VX_ASM_SUPPORT
 
 # define IFUNC_VX_IMPL(FUNC)						\
@@ -187,7 +200,6 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 
   IFUNC_VX_IMPL (wcslen);
 
-  IFUNC_VX_IMPL (strnlen);
   IFUNC_VX_IMPL (wcsnlen);
 
   IFUNC_VX_IMPL (strcpy);
diff --git a/sysdeps/s390/multiarch/strnlen-c.c b/sysdeps/s390/multiarch/strnlen-c.c
deleted file mode 100644
index 353e83ed35..0000000000
--- a/sysdeps/s390/multiarch/strnlen-c.c
+++ /dev/null
@@ -1,30 +0,0 @@
-/* Default strnlen implementation for S/390.
-   Copyright (C) 2015-2018 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 STRNLEN  __strnlen_c
-# ifdef SHARED
-#  undef libc_hidden_def
-#  define libc_hidden_def(name)					\
-  __hidden_ver1 (__strnlen_c, __GI_strnlen, __strnlen_c);	\
-  strong_alias (__strnlen_c, __strnlen_c_1);			\
-  __hidden_ver1 (__strnlen_c_1, __GI___strnlen, __strnlen_c_1);
-# endif /* SHARED */
-
-# include <string/strnlen.c>
-#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
diff --git a/sysdeps/s390/multiarch/strnlen-vx.S b/sysdeps/s390/multiarch/strnlen-vx.S
deleted file mode 100644
index fc659a956c..0000000000
--- a/sysdeps/s390/multiarch/strnlen-vx.S
+++ /dev/null
@@ -1,134 +0,0 @@
-/* Vector optimized 32/64 bit S/390 version of strnlen.
-   Copyright (C) 2015-2018 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
-
-/* size_t strnlen (const char *s, size_t maxlen)
-   Returns the number of characters in s or at most maxlen.
-
-   Register usage:
-   -r1=tmp
-   -r2=address of string
-   -r3=maxlen (number of characters to be read)
-   -r4=tmp
-   -r5=current_len and return_value
-   -v16=part of s
-*/
-ENTRY(__strnlen_vx)
-	.machine "z13"
-	.machinemode "zarch_nohighgprs"
-
-# if !defined __s390x__
-	llgfr	%r3,%r3
-# endif /* !defined __s390x__ */
-
-	clgfi	%r3,0		/* if maxlen == 0, return 0.  */
-	locgre	%r2,%r3
-	ber	%r14
-
-	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.  */
-	llgfr	%r1,%r1		/* Convert 32bit to 64bit.  */
-
-	vfenezb	%v16,%v16,%v16	/* Find element not equal with zero search.  */
-	clgr	%r1,%r3
-	locgrh	%r1,%r3		/* loaded_byte_count
-				   = min (loaded_byte_count, maxlen)  */
-
-	vlgvb	%r5,%v16,7	/* Load zero index or 16 if not found.  */
-	clr	%r5,%r1		/* If found zero within loaded bytes?  */
-	locgrl	%r2,%r5		/* Then copy return value.  */
-	blr	%r14		/* And return.  */
-
-	clgr	%r1,%r3		/* If loaded_byte_count == maxlen?  */
-	locgre	%r2,%r3		/* Then copy return value.  */
-	ber	%r14		/* And return.  */
-
-	/* 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.  */
-
-	lgr	%r1,%r5		/* If %r5 + 64 < maxlen? -> loop64.  */
-	aghi	%r1,64
-	clgrjl	%r1,%r3,.Lloop64
-
-	/* Find zero in max 64byte with aligned s.  */
-.Llt64:
-	vl	%v16,0(%r5,%r2) /* Load s.  */
-	vfenezbs %v16,%v16,%v16	/* Find element not equal with zero search.  */
-	je	.Lfound		/* Jump away if zero was found.  */
-	aghi	%r5,16
-	clgrjhe	%r5,%r3,.Lfound /* current_len >= maxlen -> end.  */
-	vl	%v16,0(%r5,%r2)
-	vfenezbs %v16,%v16,%v16
-	je	.Lfound
-	aghi	%r5,16
-	clgrjhe	%r5,%r3,.Lfound
-	vl	%v16,0(%r5,%r2)
-	vfenezbs %v16,%v16,%v16
-	je	.Lfound
-	aghi	%r5,16
-	clgrjhe	%r5,%r3,.Lfound
-	vl	%v16,0(%r5,%r2)
-	vfenezbs %v16,%v16,%v16
-	j	.Lfound
-
-.Lfound48:
-	aghi	%r5,16
-.Lfound32:
-	aghi	%r5,16
-.Lfound16:
-	aghi	%r5,16
-.Lfound:
-	vlgvb	%r4,%v16,7	/* Load byte index of zero or 16 if no zero.  */
-	algr	%r5,%r4
-
-	clgr	%r5,%r3
-	locgrh	%r5,%r3		/* Return min (current_len, maxlen).  */
-	lgr	%r2,%r5
-	br	%r14
-
-	/* Find zero in 16 byte aligned loop.  */
-.Lloop64:
-	vl	%v16,0(%r5,%r2) /* Load s.  */
-	vfenezbs %v16,%v16,%v16	/* Find element not equal with zero search.  */
-	je	.Lfound		/* Jump away if zero was found.  */
-	vl	%v16,16(%r5,%r2)
-	vfenezbs %v16,%v16,%v16
-	je	.Lfound16
-	vl	%v16,32(%r5,%r2)
-	vfenezbs %v16,%v16,%v16
-	je	.Lfound32
-	vl	%v16,48(%r5,%r2)
-	vfenezbs %v16,%v16,%v16
-	je	.Lfound48
-
-	aghi	%r5,64
-	lgr	%r1,%r5		/* If %r5 + 64 < maxlen? -> loop64.  */
-	aghi	%r1,64
-	clgrjl	%r1,%r3,.Lloop64
-
-	j	.Llt64
-END(__strnlen_vx)
-#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
diff --git a/sysdeps/s390/multiarch/strnlen.c b/sysdeps/s390/multiarch/strnlen.c
deleted file mode 100644
index 0f9cff5d69..0000000000
--- a/sysdeps/s390/multiarch/strnlen.c
+++ /dev/null
@@ -1,32 +0,0 @@
-/* Multiple versions of strnlen.
-   Copyright (C) 2015-2018 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 strnlen __redirect_strnlen
-# define __strnlen __redirect___strnlen
-# include <string.h>
-# undef strnlen
-# undef __strnlen
-# include <ifunc-resolve.h>
-
-s390_vx_libc_ifunc_redirected (__redirect___strnlen, __strnlen)
-weak_alias (__strnlen, strnlen)
-
-#else
-# include <string/strnlen.c>
-#endif /* !(defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)) */