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/* The assembly function for memset. C-SKY ABIV2 version.
Copyright (C) 2018-2020 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
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
ENTRY (memset)
/* Test if len less than 4 bytes. */
mov r12, r0
cmplti r2, 8
bt .L_set_by_byte
andi r13, r0, 3
movi r19, 4
/* Test if dest is not 4 bytes aligned. */
bnez r13, .L_dest_not_aligned
/* Hardware can handle unaligned access directly. */
.L_dest_aligned:
zextb r1, r1
mov r3, r1
lsli r1, 8
or r1, r3
lsli r3, r1, 16
or r3, r1
/* If dest is aligned, then copy. */
zext r18, r2, 31, 4
/* Test if len less than 16 bytes. */
bez r18, .L_len_less_16bytes
LABLE_ALIGN
.L_len_larger_16bytes:
stw r3, (r0, 0)
stw r3, (r0, 4)
stw r3, (r0, 8)
stw r3, (r0, 12)
PRE_BNEZAD (r18)
addi r0, 16
BNEZAD (r18, .L_len_larger_16bytes)
.L_len_less_16bytes:
zext r18, r2, 3, 2
andi r2, 3
bez r18, .L_set_by_byte
.L_len_less_16bytes_loop:
stw r3, (r0, 0)
PRE_BNEZAD (r18)
addi r0, 4
BNEZAD (r18, .L_len_less_16bytes_loop)
/* Test if len less than 4 bytes. */
.L_set_by_byte:
zext r18, r2, 2, 0
bez r18, .L_return
.L_set_by_byte_loop:
stb r1, (r0, 0)
PRE_BNEZAD (r18)
addi r0, 1
BNEZAD (r18, .L_set_by_byte_loop)
.L_return:
mov r0, r12
rts
/* If dest is not aligned, just set some bytes makes the dest
align. */
.L_dest_not_aligned:
sub r13, r19, r13
sub r2, r13
.L_dest_not_aligned_loop:
/* Makes the dest align. */
stb r1, (r0, 0)
PRE_BNEZAD (r13)
addi r0, 1
BNEZAD (r13, .L_dest_not_aligned_loop)
cmplti r2, 8
bt .L_set_by_byte
/* Check whether the src is aligned. */
br .L_dest_aligned
END (memset)
libc_hidden_builtin_def (memset)
.weak memset
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