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diff --git a/REORG.TODO/sysdeps/s390/s390-64/bcopy.S b/REORG.TODO/sysdeps/s390/s390-64/bcopy.S
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+/* bcopy -- copy a block from source to destination.  64 bit S/390 version.
+   This file is part of the GNU C Library.
+   Copyright (C) 2000-2017 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 source
+     %r3 = address of destination
+     %r4 = number of bytes to copy.  */
+
+#include "sysdep.h"
+#include "asm-syntax.h"
+
+	.text
+ENTRY(__bcopy)
+	ltgr	%r1,%r4		    # zero bcopy ?
+	jz	.L4
+	clgr	%r2,%r3		    # check against destructive overlap
+	jnl	.L0
+	algr	%r1,%r2
+	clgr	%r1,%r3
+	jh	.L7
+.L0:	aghi	%r4,-1		    # length - 1
+	srlg	%r1,%r4,8
+	ltgr	%r1,%r1             # < 256 bytes to move ?
+	jz	.L2
+	cghi    %r1,255             # > 1MB to move ?
+	jh      .L5
+.L1:	mvc	0(256,%r3),0(%r2)   # move in 256 byte chunks
+	la	%r2,256(%r2)
+	la	%r3,256(%r3)
+	brctg	%r1,.L1
+.L2:	bras	%r1,.L3		    # setup base pointer for execute
+	mvc	0(1,%r3),0(%r2)	    # instruction for execute
+.L3:	ex	%r4,0(%r1)	    # execute mvc with length ((%r4)&255)+1
+.L4:	br	%r14
+	# data copies > 1MB are faster with mvcle.
+.L5:	aghi    %r4,1               # length + 1
+	lgr	%r5,%r4	            # source length
+	lgr	%r4,%r2             # source address
+	lgr	%r2,%r3             # set destination
+	lgr	%r3,%r5             # destination length = source length
+.L6:	mvcle	%r2,%r4,0           # thats it, MVCLE is your friend
+	jo	.L6
+	br	%r14
+.L7:				    # destructive overlay, can not use mvcle
+	lgr	%r1,%r2		    # bcopy is called with source,dest
+	lgr	%r2,%r3		    # memmove with dest,source! Oh, well...
+	lgr	%r3,%r1
+	jg	HIDDEN_BUILTIN_JUMPTARGET(memmove)
+
+END(__bcopy)
+
+#ifndef NO_WEAK_ALIAS
+weak_alias (__bcopy, bcopy)
+#endif
+