/* memcpy - copy a block from source to destination. 64 bit S/390 version.
Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
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.
+ 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
- Library General Public License for more details.
+ Lesser 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. */
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
/* INPUT PARAMETERS
%r2 = address of destination memory area
jz .L3
aghi %r4,-1 # length - 1
lgr %r1,%r2 # copy destination address
- srag %r5,%r4,8
+ srlg %r5,%r4,8
+ ltgr %r5,%r5 # < 256 bytes to mvoe ?
jz .L1
+ chi %r6,255 # > 1 MB to move ?
+ jh .L4
.L0: mvc 0(256,%r1),0(%r3) # move in 256 byte chunks
la %r1,256(%r1)
la %r3,256(%r3)
mvc 0(1,%r1),0(%r3) # instruction for execute
.L2: ex %r4,0(%r5) # execute mvc with length ((%r4)&255)+1
.L3: br %r14
+ # data copies > 1MB are faster with mvcle.
+.L4: 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
+.L5: mvcle %r2,%r4,0 # thats it, MVCLE is your friend
+ jo .L5
+ lgr %r2,%r1 # return destination address
+ br %r14
END(memcpy)