1/*
2 * Copyright 2011 Tilera Corporation. All Rights Reserved.
3 *
4 *   This program is free software; you can redistribute it and/or
5 *   modify it under the terms of the GNU General Public License
6 *   as published by the Free Software Foundation, version 2.
7 *
8 *   This program is distributed in the hope that it will be useful, but
9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 *   NON INFRINGEMENT.  See the GNU General Public License for
12 *   more details.
13 */
14
15#include <linux/types.h>
16#include <linux/string.h>
17#include <linux/module.h>
18#include "string-endian.h"
19
20size_t strlen(const char *s)
21{
22	/* Get an aligned pointer. */
23	const uintptr_t s_int = (uintptr_t) s;
24	const uint64_t *p = (const uint64_t *)(s_int & -8);
25
26	/* Read and MASK the first word. */
27	uint64_t v = *p | MASK(s_int);
28
29	uint64_t bits;
30	while ((bits = __insn_v1cmpeqi(v, 0)) == 0)
31		v = *++p;
32
33	return ((const char *)p) + (CFZ(bits) >> 3) - s;
34}
35EXPORT_SYMBOL(strlen);
36