| * Copyright 2010 Tilera Corporation. All Rights Reserved. |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation, version 2. |
| * This program 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, GOOD TITLE or |
| * NON INFRINGEMENT. See the GNU General Public License for |
| #include <linux/string.h> |
| #include <linux/module.h> |
| size_t strlen(const char *s) |
| /* Get an aligned pointer. */ |
| const uintptr_t s_int = (uintptr_t) s; |
| const uint32_t *p = (const uint32_t *)(s_int & -4); |
| /* Read the first word, but force bytes before the string to be nonzero. |
| * This expression works because we know shift counts are taken mod 32. |
| uint32_t v = *p | ((1 << (s_int << 3)) - 1); |
| while ((bits = __insn_seqb(v, 0)) == 0) |
| return ((const char *)p) + (__insn_ctz(bits) >> 3) - s; |