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/* Copyright (C) 2000-2021 Free Software Foundation, Inc.
Contributed by David Mosberger (davidm@cs.arizona.edu).
EV67 optimized by Rick Gorton <rick.gorton@alpha-processor.com>.
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/>. */
/* Finds length of a 0-terminated string. */
#include <sysdep.h>
.arch ev6
.set noreorder
.set noat
ENTRY(strlen)
#ifdef PROF
ldgp gp, 0(pv)
lda AT, _mcount
jsr AT, (AT), _mcount
.prologue 1
#else
.prologue 0
#endif
ldq_u $1, 0($16) # L : load first quadword ($16 may be misaligned)
lda $2, -1($31) # E :
insqh $2, $16, $2 # U :
andnot $16, 7, $0 # E :
or $2, $1, $1 # E :
cmpbge $31, $1, $2 # E : $2 <- bitmask: bit i == 1 <==> i-th byte == 0
nop # E :
bne $2, $found # U :
$loop: ldq $1, 8($0) # L :
addq $0, 8, $0 # E : addr += 8
cmpbge $31, $1, $2 # E :
beq $2, $loop # U :
$found:
cttz $2, $3 # U0 :
addq $0, $3, $0 # E :
subq $0, $16, $0 # E :
ret $31, ($26) # L0 :
END(strlen)
libc_hidden_builtin_def (strlen)
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