glibc/sysdeps/arm/memset.S

68 lines
1.7 KiB
ArmAsm

/* Copyright (C) 1998, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Philip Blundell <philb@gnu.org>
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. */
#include <sysdep.h>
/* void *memset (dstpp, c, len) */
ENTRY(memset)
mov r3, r0
cmp r2, #8
bcc 2f @ less than 8 bytes to move
1:
tst r3, #3 @ aligned yet?
strneb r1, [r3], #1
subne r2, r2, #1
bne 1b
orr r1, r1, r1, lsl $8
orr r1, r1, r1, lsl $16
1:
subs r2, r2, #8
strcs r1, [r3], #4 @ store up to 32 bytes per loop iteration
strcs r1, [r3], #4
subcss r2, r2, #8
strcs r1, [r3], #4
strcs r1, [r3], #4
subcss r2, r2, #8
strcs r1, [r3], #4
strcs r1, [r3], #4
subcss r2, r2, #8
strcs r1, [r3], #4
strcs r1, [r3], #4
bcs 1b
and r2, r2, #7
2:
subs r2, r2, #1 @ store up to 4 bytes per loop iteration
strcsb r1, [r3], #1
subcss r2, r2, #1
strcsb r1, [r3], #1
subcss r2, r2, #1
strcsb r1, [r3], #1
subcss r2, r2, #1
strcsb r1, [r3], #1
bcs 2b
DO_RET(lr)
END(memset)
libc_hidden_builtin_def (memset)