s390: Remove bzero optimizations

The symbol is not present in current POSIX specification and compiler
already generates memset call.

sysdeps/s390/Makefile

@@ -66,7 +66,7 @@ endif
 endif
 
 ifeq ($(subdir),string)
-sysdep_routines += bzero memset memset-z900 \
+sysdep_routines += memset memset-z900 \
 		   memcmp memcmp-z900 \
 		   mempcpy memcpy memcpy-z900 \
 		   memmove memmove-c \

sysdeps/s390/bzero.c

@@ -1,47 +0,0 @@
-/* Multiple versions of bzero.
-   Copyright (C) 2018-2022 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
-   <https://www.gnu.org/licenses/>.  */
-
-#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_expr_stfle_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

sysdeps/s390/ifunc-memset.h

@@ -25,19 +25,16 @@
 
 #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
@@ -51,24 +48,18 @@
 
 #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

sysdeps/s390/memset-z900.S

@@ -24,11 +24,7 @@
 /* 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
 
@@ -47,12 +43,6 @@
 #  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__
@@ -100,14 +90,6 @@ 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"
@@ -141,14 +123,6 @@ 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"
@@ -204,10 +178,6 @@ 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)

sysdeps/s390/multiarch/ifunc-impl-list.c

@@ -102,21 +102,6 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 # endif
 # if HAVE_MEMSET_Z900_G5
 	      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 */