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/* Copyright (C) 1999-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
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>
/* size_t strlen (const char *s) */
ENTRY(strlen)
mov r4, r0
and #3, r0
tst r0, r0
bt/s 1f
mov #0, r2
add #-1, r0
shll2 r0
shll r0
braf r0
nop
mov.b @r4+, r1
tst r1, r1
bt 8f
add #1, r2
mov.b @r4+, r1
tst r1, r1
bt 8f
add #1, r2
mov.b @r4+, r1
tst r1, r1
bt 8f
add #1, r2
1:
mov #0, r3
2:
mov.l @r4+, r1
cmp/str r3, r1
bf/s 2b
add #4, r2
add #-4, r2
#ifdef __BIG_ENDIAN__
swap.b r1, r1
swap.w r1, r1
swap.b r1, r1
#endif
extu.b r1, r0
tst r0, r0
bt/s 8f
shlr8 r1
add #1, r2
extu.b r1, r0
tst r0, r0
bt/s 8f
shlr8 r1
add #1, r2
extu.b r1, r0
tst r0, r0
bt 8f
add #1, r2
8:
rts
mov r2, r0
END(strlen)
libc_hidden_builtin_def (strlen)
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