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+/* Copyright (C) 2000 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 Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+/* 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)