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/* Copyright (C) 1998 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, see
<http://www.gnu.org/licenses/>. */
#include <features.h>
#include <sys/syscall.h>
#include <bits/arm_asm.h>
.text
.global memset
.type memset,%function
.align 4
#if defined(THUMB1_ONLY)
.thumb_func
memset:
mov ip, r0
cmp r2, #8 @ at least 8 bytes to do?
bcc 2f
lsl r3, r1, #8
orr r1, r3
lsl r3, r1, #16
orr r1, r3
mov r3, #3
1: @ Fill up to the first word boundary
tst r0, r3
beq 1f
strb r1, [r0]
add r0, r0, #1
sub r2, r2, #1
b 1b
1: @ Fill aligned words
str r1, [r0]
add r0, r0, #4
sub r2, r2, #4
cmp r2, #4
bcs 1b
2: @ Fill the remaining bytes
cmp r2, #0
beq 2f
1:
strb r1, [r0]
add r0, r0, #1
sub r2, r2, #1
bne 1b
2:
mov r0, ip
bx lr
#else
memset:
mov a4, a1
cmp a3, $8 @ at least 8 bytes to do?
blt 2f
orr a2, a2, a2, lsl $8
orr a2, a2, a2, lsl $16
1:
tst a4, $3 @ aligned yet?
#if defined(__thumb2__)
itt ne
strbne a2, [a4], $1
subne a3, a3, $1
#else
strneb a2, [a4], $1
subne a3, a3, $1
#endif
bne 1b
mov ip, a2
1:
cmp a3, $8 @ 8 bytes still to do?
blt 2f
stmia a4!, {a2, ip}
sub a3, a3, $8
cmp a3, $8 @ 8 bytes still to do?
blt 2f
stmia a4!, {a2, ip}
sub a3, a3, $8
cmp a3, $8 @ 8 bytes still to do?
blt 2f
stmia a4!, {a2, ip}
sub a3, a3, $8
cmp a3, $8 @ 8 bytes still to do?
#if defined(__thumb2__)
itt ge
stmiage a4!, {a2, ip}
subge a3, a3, $8
#else
stmgeia a4!, {a2, ip}
subge a3, a3, $8
#endif
bge 1b
2:
movs a3, a3 @ anything left?
IT(t, eq)
#if defined(__USE_BX__)
bxeq lr
#else
moveq pc, lr @ nope
#endif
#if defined (__thumb2__)
1:
strb a2, [a4], #1
subs a3, a3, #1
bne 1b
bx lr
#else
rsb a3, a3, $7
add pc, pc, a3, lsl $2
mov r0, r0
strb a2, [a4], $1
strb a2, [a4], $1
strb a2, [a4], $1
strb a2, [a4], $1
strb a2, [a4], $1
strb a2, [a4], $1
strb a2, [a4], $1
#if defined(__USE_BX__)
bx lr
#else
mov pc, lr
#endif
#endif
#endif
.size memset,.-memset
libc_hidden_def(memset)
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