mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 09:01:07 +00:00
87 lines
3.0 KiB
ArmAsm
87 lines
3.0 KiB
ArmAsm
/* bcopy -- copy a block from source to destination. S/390 version.
|
|
This file is part of the GNU C Library.
|
|
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 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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
/* 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)
|
|
ltr %r1,%r4 # zero bcopy ?
|
|
jz .L4
|
|
clr %r2,%r3 # check against destructive overlap
|
|
jnl .L0
|
|
alr %r1,%r2
|
|
clr %r1,%r3
|
|
jh .L7
|
|
.L0: ahi %r4,-1 # length - 1
|
|
lr %r1,%r4
|
|
srl %r1,8
|
|
ltr %r1,%r1 # < 256 bytes to move ?
|
|
jz .L2
|
|
chi %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)
|
|
brct %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: ahi %r4,1 # length + 1
|
|
lr %r5,%r4 # source length
|
|
lr %r4,%r2 # source address
|
|
lr %r2,%r3 # set destination
|
|
lr %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
|
|
lr %r1,%r2 # bcopy is called with source,dest
|
|
lr %r2,%r3 # memmove with dest,source! Oh, well...
|
|
lr %r3,%r1
|
|
basr %r1,0
|
|
.L8:
|
|
#ifdef PIC
|
|
al %r1,.L9-.L8(%r1) # get address of global offset table
|
|
# load address of memmove
|
|
l %r1,memmove@GOT12(%r1)
|
|
br %r1
|
|
.L9: .long _GLOBAL_OFFSET_TABLE_-.L8
|
|
#else
|
|
al %r1,.L9-.L8(%r1) # load address of memmove
|
|
br %r1 # jump to memmove
|
|
.L9: .long memmove-.L8
|
|
#endif
|
|
|
|
END(__bcopy)
|
|
|
|
#ifndef NO_WEAK_ALIAS
|
|
weak_alias (__bcopy, bcopy)
|
|
#endif
|
|
|