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/*
* Copyright (c) 2015 ARM Ltd
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the company may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
.arm
.syntax unified
.global memset
.type memset, %function
memset:
tst r0, #3
stmfd sp!, {r4, lr}
beq 10f
cmp r2, #0
sub r2, r2, #1
beq 9f
and ip, r1, #255
mov r3, r0
b 2f
1:
cmp r2, #0
sub r2, r2, #1
beq 9f
2:
strb ip, [r3], #1
tst r3, #3
bne 1b
3:
cmp r2, #3
bls 7f
and lr, r1, #255
orr lr, lr, lr, asl #8
cmp r2, #15
orr lr, lr, lr, asl #16
bls 5f
mov r4, r2
add ip, r3, #16
4:
sub r4, r4, #16
cmp r4, #15
str lr, [ip, #-16]
str lr, [ip, #-12]
str lr, [ip, #-8]
str lr, [ip, #-4]
add ip, ip, #16
bhi 4b
sub ip, r2, #16
bic ip, ip, #15
and r2, r2, #15
add ip, ip, #16
cmp r2, #3
add r3, r3, ip
bls 7f
5:
mov r4, r3
mov ip, r2
6:
sub ip, ip, #4
cmp ip, #3
str lr, [r4], #4
bhi 6b
sub ip, r2, #4
bic ip, ip, #3
add ip, ip, #4
add r3, r3, ip
and r2, r2, #3
7:
cmp r2, #0
andne r1, r1, #255
addne r2, r3, r2
beq 9f
8:
strb r1, [r3], #1
cmp r3, r2
bne 8b
9:
ldmfd sp!, {r4, lr}
bx lr
10:
mov r3, r0
b 3b
.size memset, . - memset
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