S390: Implement bzero with memset.

This patch removes the bzero s390 implementation with mvcle and
adds entry points for bzero in memset ifunc variants.
Therefore an ifunc resolver is implemented for bzero, too.

ChangeLog:

	* sysdeps/s390/s390-32/bzero.S: Delete file.
	* sysdeps/s390/s390-64/bzero.S: Likewise.
	* sysdeps/s390/Makefile (sysdep_routines): Add bzero.
	* sysdeps/s390/bzero.c: New file.
	* sysdeps/s390/memset-z900.S: Add bzero entry points.
	* sysdeps/s390/ifunc-memset.h: Add bzero function macros.
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Add bzero ifunc variants.

7 files changed, 100 insertions, 68 deletions

diff --git a/ChangeLog b/ChangeLog
index a911aeb..509acf9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,16 @@
 2018-12-18  Stefan Liebler  <stli@linux.ibm.com>
 
+	* sysdeps/s390/s390-32/bzero.S: Delete file.
+	* sysdeps/s390/s390-64/bzero.S: Likewise.
+	* sysdeps/s390/Makefile (sysdep_routines): Add bzero.
+	* sysdeps/s390/bzero.c: New file.
+	* sysdeps/s390/memset-z900.S: Add bzero entry points.
+	* sysdeps/s390/ifunc-memset.h: Add bzero function macros.
+	* sysdeps/s390/multiarch/ifunc-impl-list.c
+	(__libc_ifunc_impl_list): Add bzero ifunc variants.
+
+2018-12-18  Stefan Liebler  <stli@linux.ibm.com>
+
 	* sysdeps/s390/ifunc-memset.h: New File.
 	* sysdeps/s390/memset.S: Move to ...
 	* sysdeps/s390/memset-z900.S ... here.
diff --git a/sysdeps/s390/Makefile b/sysdeps/s390/Makefile
index f90a41d..31ae2ce 100644
--- a/sysdeps/s390/Makefile
+++ b/sysdeps/s390/Makefile
@@ -54,5 +54,5 @@ endif
 endif
 
 ifeq ($(subdir),string)
-sysdep_routines += memset memset-z900
+sysdep_routines += bzero memset memset-z900
 endif
diff --git a/sysdeps/s390/s390-32/bzero.S b/sysdeps/s390/bzero.c
index 897aa21..9f8d957 100644
--- a/sysdeps/s390/s390-32/bzero.S
+++ b/sysdeps/s390/bzero.c
@@ -1,7 +1,6 @@
-/* bzero -- set a block of memory to zero.  IBM S390 version
+/* Multiple versions of bzero.
+   Copyright (C) 2018 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
-   Copyright (C) 2000-2018 Free Software Foundation, Inc.
-   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
 
    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -17,26 +16,32 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-/*
- * R2 = address to memory area
- * R3 = number of bytes to fill
- */
-
-#include "sysdep.h"
-#include "asm-syntax.h"
-
-	.text
-ENTRY(__bzero)
-	ltr     %r3,%r3
-	jz      .L1
-	sr      %r1,%r1             # set pad byte to zero
-	sr      %r4,%r4             # no source for MVCLE, only a pad byte
-	sr      %r5,%r5
-.L0:    mvcle   %r2,%r4,0(%r1)      # thats it, MVCLE is your friend
-	jo      .L0
-.L1:    br      %r14
-END(__bzero)
-
-#ifndef NO_WEAK_ALIAS
+#include <ifunc-memset.h>
+#if HAVE_MEMSET_IFUNC
+# include <string.h>
+# include <ifunc-resolve.h>
+
+# if HAVE_MEMSET_Z900_G5
+extern __typeof (__bzero) BZERO_Z900_G5 attribute_hidden;
+# endif
+
+# if HAVE_MEMSET_Z10
+extern __typeof (__bzero) BZERO_Z10 attribute_hidden;
+# endif
+
+# if HAVE_MEMSET_Z196
+extern __typeof (__bzero) BZERO_Z196 attribute_hidden;
+# endif
+
+s390_libc_ifunc_expr (__bzero, __bzero,
+		      ({
+			s390_libc_ifunc_init ();
+			(HAVE_MEMSET_Z196 && S390_IS_Z196 (stfle_bits))
+			  ? BZERO_Z196
+			  : (HAVE_MEMSET_Z10 && S390_IS_Z10 (stfle_bits))
+			  ? BZERO_Z10
+			  : BZERO_DEFAULT;
+		      })
+		      )
 weak_alias (__bzero, bzero)
 #endif
diff --git a/sysdeps/s390/ifunc-memset.h b/sysdeps/s390/ifunc-memset.h
index 9a13b10..32bc155 100644
--- a/sysdeps/s390/ifunc-memset.h
+++ b/sysdeps/s390/ifunc-memset.h
@@ -25,16 +25,19 @@
 
 #if defined HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
 # define MEMSET_DEFAULT		MEMSET_Z196
+# define BZERO_DEFAULT		BZERO_Z196
 # define HAVE_MEMSET_Z900_G5	0
 # define HAVE_MEMSET_Z10	0
 # define HAVE_MEMSET_Z196	1
 #elif defined HAVE_S390_MIN_Z10_ZARCH_ASM_SUPPORT
 # define MEMSET_DEFAULT		MEMSET_Z10
+# define BZERO_DEFAULT		BZERO_Z10
 # define HAVE_MEMSET_Z900_G5	0
 # define HAVE_MEMSET_Z10	1
 # define HAVE_MEMSET_Z196	HAVE_MEMSET_IFUNC
 #else
 # define MEMSET_DEFAULT		MEMSET_Z900_G5
+# define BZERO_DEFAULT		BZERO_Z900_G5
 # define HAVE_MEMSET_Z900_G5	1
 # define HAVE_MEMSET_Z10	HAVE_MEMSET_IFUNC
 # define HAVE_MEMSET_Z196	HAVE_MEMSET_IFUNC
@@ -48,18 +51,24 @@
 
 #if HAVE_MEMSET_Z900_G5
 # define MEMSET_Z900_G5		__memset_default
+# define BZERO_Z900_G5		__bzero_default
 #else
 # define MEMSET_Z900_G5		NULL
+# define BZERO_Z900_G5		NULL
 #endif
 
 #if HAVE_MEMSET_Z10
 # define MEMSET_Z10		__memset_z10
+# define BZERO_Z10		__bzero_z10
 #else
 # define MEMSET_Z10		NULL
+# define BZERO_Z10		NULL
 #endif
 
 #if HAVE_MEMSET_Z196
 # define MEMSET_Z196		__memset_z196
+# define BZERO_Z196		__bzero_z196
 #else
 # define MEMSET_Z196		NULL
+# define BZERO_Z196		NULL
 #endif
diff --git a/sysdeps/s390/memset-z900.S b/sysdeps/s390/memset-z900.S
index eaf1340..bfc659a 100644
--- a/sysdeps/s390/memset-z900.S
+++ b/sysdeps/s390/memset-z900.S
@@ -22,10 +22,14 @@
 #include "asm-syntax.h"
 #include <ifunc-memset.h>
 
-/* INPUT PARAMETERS
+/* INPUT PARAMETERS - MEMSET
      %r2 = address of memory area
      %r3 = byte to fill memory with
-     %r4 = number of bytes to fill.  */
+     %r4 = number of bytes to fill.
+
+   INPUT PARAMETERS - BZERO
+     %r2 = address of memory area
+     %r3 = number of bytes to fill.  */
 
        .text
 
@@ -44,7 +48,14 @@
 #  define BRCTG	brct
 # endif /* ! defined __s390x__  */
 
+ENTRY(BZERO_Z900_G5)
+	LGR	%r4,%r3
+	xr	%r3,%r3
+	j	.L_Z900_G5_start
+END(BZERO_Z900_G5)
+
 ENTRY(MEMSET_Z900_G5)
+.L_Z900_G5_start:
 #if defined __s390x__
 	.machine "z900"
 #else
@@ -90,7 +101,16 @@ END(MEMSET_Z900_G5)
 #endif /*  HAVE_MEMSET_Z900_G5  */
 
 #if HAVE_MEMSET_Z10
+ENTRY(BZERO_Z10)
+	.machine "z10"
+	.machinemode "zarch_nohighgprs"
+	lgr	%r4,%r3
+	xr	%r3,%r3
+	j	.L_Z10_start
+END(BZERO_Z10)
+
 ENTRY(MEMSET_Z10)
+.L_Z10_start:
 	.machine "z10"
 	.machinemode "zarch_nohighgprs"
 # if !defined __s390x__
@@ -122,7 +142,16 @@ END(MEMSET_Z10)
 #endif /* HAVE_MEMSET_Z10  */
 
 #if HAVE_MEMSET_Z196
+ENTRY(BZERO_Z196)
+	.machine "z196"
+	.machinemode "zarch_nohighgprs"
+	lgr	%r4,%r3
+	xr	%r3,%r3
+	j	.L_Z196_start
+END(BZERO_Z196)
+
 ENTRY(MEMSET_Z196)
+.L_Z196_start:
 	.machine "z196"
 	.machinemode "zarch_nohighgprs"
 # if !defined __s390x__
@@ -177,6 +206,10 @@ END(__memset_mvcle)
 /* If we don't use ifunc, define an alias for memset here.
    Otherwise see sysdeps/s390/memset.c.  */
 strong_alias (MEMSET_DEFAULT, memset)
+/* Same for bzero.  If ifunc is used, see
+   sysdeps/s390/bzero.c.  */
+strong_alias (BZERO_DEFAULT, __bzero)
+weak_alias (__bzero, bzero)
 #endif
 
 #if defined SHARED && IS_IN (libc)
diff --git a/sysdeps/s390/multiarch/ifunc-impl-list.c b/sysdeps/s390/multiarch/ifunc-impl-list.c
index 2f671ea..253f360 100644
--- a/sysdeps/s390/multiarch/ifunc-impl-list.c
+++ b/sysdeps/s390/multiarch/ifunc-impl-list.c
@@ -61,6 +61,21 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 	      IFUNC_IMPL_ADD (array, i, memset, 1, MEMSET_Z900_G5)
 # endif
 	      )
+
+  /* Note: bzero is implemented in memset.  */
+  IFUNC_IMPL (i, name, bzero,
+# if HAVE_MEMSET_Z196
+	      IFUNC_IMPL_ADD (array, i, bzero,
+			      S390_IS_Z196 (stfle_bits), BZERO_Z196)
+# endif
+# if HAVE_MEMSET_Z10
+	      IFUNC_IMPL_ADD (array, i, bzero,
+			      S390_IS_Z10 (stfle_bits), BZERO_Z10)
+# endif
+# if HAVE_MEMSET_Z900_G5
+	      IFUNC_IMPL_ADD (array, i, bzero, 1, BZERO_Z900_G5)
+# endif
+	      )
 #endif /* HAVE_MEMSET_IFUNC */
 
   IFUNC_IMPL (i, name, memcmp,
diff --git a/sysdeps/s390/s390-64/bzero.S b/sysdeps/s390/s390-64/bzero.S
deleted file mode 100644
index b321665..0000000
--- a/sysdeps/s390/s390-64/bzero.S
+++ /dev/null
@@ -1,41 +0,0 @@
-/* bzero -- set a block of memory to zero.  64 bit S/390 version.
-   This file is part of the GNU C Library.
-   Copyright (C) 2001-2018 Free Software Foundation, Inc.
-   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
-
-   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/>.  */
-
-/* INPUT PARAMETERS
-     %r2 = address of memory area
-     %r3 = number of bytes to fill.  */
-
-#include "sysdep.h"
-#include "asm-syntax.h"
-
-	.text
-ENTRY(__bzero)
-	ltgr	%r3,%r3
-	jz	.L1
-	sgr	%r1,%r1		    # set pad byte to zero
-	sgr	%r4,%r4		    # no source for MVCLE, only a pad byte
-	sgr	%r5,%r5
-.L0:	mvcle	%r2,%r4,0(%r1)	    # thats it, MVCLE is your friend
-	jo	.L0
-.L1:	br	%r14
-END(__bzero)
-
-#ifndef NO_WEAK_ALIAS
-weak_alias (__bzero, bzero)
-#endif