glibc/sysdeps/s390/s390-32/memcpy.S

90 lines
2.6 KiB
ArmAsm

/* memcpy - copy a block from source to destination. S/390 version.
Copyright (C) 2012-2017 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
<http://www.gnu.org/licenses/>. */
#include "sysdep.h"
#include "asm-syntax.h"
/* INPUT PARAMETERS
%r2 = address of destination memory area
%r3 = address of source memory area
%r4 = number of bytes to copy. */
.text
ENTRY(__mempcpy)
.machine "g5"
lr %r1,%r2 # Use as dest
la %r2,0(%r4,%r2) # Return dest + n
j .L_G5_start
END(__mempcpy)
#ifndef USE_MULTIARCH
libc_hidden_def (__mempcpy)
weak_alias (__mempcpy, mempcpy)
libc_hidden_builtin_def (mempcpy)
#endif
ENTRY(memcpy)
.machine "g5"
lr %r1,%r2 # r1: Use as dest ; r2: Return dest
.L_G5_start:
ltr %r4,%r4
je .L_G5_99
ahi %r4,-1
lr %r5,%r4
srl %r5,8
ltr %r5,%r5
jne .L_G5_13
.L_G5_4:
basr %r5,0
.L_G5_16:
ex %r4,.L_G5_17-.L_G5_16(%r5)
.L_G5_99:
br %r14
.L_G5_13:
chi %r5,4096 # Switch to mvcle for copies >1MB
jh __memcpy_mvcle
.L_G5_12:
mvc 0(256,%r1),0(%r3)
la %r1,256(%r1)
la %r3,256(%r3)
brct %r5,.L_G5_12
j .L_G5_4
.L_G5_17:
mvc 0(1,%r1),0(%r3)
END(memcpy)
#ifndef USE_MULTIARCH
libc_hidden_builtin_def (memcpy)
#endif
ENTRY(__memcpy_mvcle)
# Using as standalone function will result in unexpected
# results since the length field is incremented by 1 in order to
# compensate the changes already done in the functions above.
lr %r0,%r2 # backup return dest [ + n ]
ahi %r4,1 # length + 1
lr %r5,%r4 # source length
lr %r4,%r3 # source address
lr %r2,%r1 # destination address
lr %r3,%r5 # destination length = source length
.L_MVCLE_1:
mvcle %r2,%r4,0 # thats it, MVCLE is your friend
jo .L_MVCLE_1
lr %r2,%r0 # return destination address
br %r14
END(__memcpy_mvcle)