mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 21:10:07 +00:00
99 lines
2.3 KiB
ArmAsm
99 lines
2.3 KiB
ArmAsm
/* The assembly function for memset. C-SKY ABIV2 version.
|
|
Copyright (C) 2018-2023 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
|