diff options
Diffstat (limited to 'arch/arm64/lib/memchr.S')
| -rw-r--r-- | arch/arm64/lib/memchr.S | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/arm64/lib/memchr.S b/arch/arm64/lib/memchr.S new file mode 100644 index 00000000000..8636b754916 --- /dev/null +++ b/arch/arm64/lib/memchr.S @@ -0,0 +1,44 @@ +/* + * Based on arch/arm/lib/memchr.S + * + * Copyright (C) 1995-2000 Russell King + * Copyright (C) 2013 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> +#include <asm/assembler.h> + +/* + * Find a character in an area of memory. + * + * Parameters: + * x0 - buf + * x1 - c + * x2 - n + * Returns: + * x0 - address of first occurrence of 'c' or 0 + */ +ENTRY(memchr) + and w1, w1, #0xff +1: subs x2, x2, #1 + b.mi 2f + ldrb w3, [x0], #1 + cmp w3, w1 + b.ne 1b + sub x0, x0, #1 + ret +2: mov x0, #0 + ret +ENDPROC(memchr) |