1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Based on arch/arm/lib/memchr.S 4 * 5 * Copyright (C) 1995-2000 Russell King 6 * Copyright (C) 2013 ARM Ltd. 7 */ 8 9 #include <linux/linkage.h> 10 #include <asm/assembler.h> 11 12 /* 13 * Find a character in an area of memory. 14 * 15 * Parameters: 16 * x0 - buf 17 * x1 - c 18 * x2 - n 19 * Returns: 20 * x0 - address of first occurrence of 'c' or 0 21 */ 22 SYM_FUNC_START_WEAK_PI(memchr) 23 and w1, w1, #0xff 24 1: subs x2, x2, #1 25 b.mi 2f 26 ldrb w3, [x0], #1 27 cmp w3, w1 28 b.ne 1b 29 sub x0, x0, #1 30 ret 31 2: mov x0, #0 32 ret 33 SYM_FUNC_END_PI(memchr) 34 EXPORT_SYMBOL_NOKASAN(memchr) 35