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/* Set a block of memory to some byte value. For IBM S390
Copyright (C) 2000, 2001 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/*
* R2 = address to destination memory area
* R3 = address to source memory area
* R4 = number of bytes to copy
*/
#include "sysdep.h"
#include "asm-syntax.h"
.text
ENTRY(memcpy)
ltr %r5,%r4
jz .L1
lr %r4,%r3 # %r4/%r5 = source ptr/len
lr %r3,%r5 # %r2/%r3 = dest ptr/len
lr %r0,%r2 # save source address
.L0: mvcle %r2,%r4,0 # thats it, MVCLE is your friend
jo .L0
lr %r2,%r0 # return value is source address
.L1:
br %r14
END(memset)
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