1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Based on arch/arm/lib/strchr.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 the first occurrence of a character in a string. 14 * 15 * Parameters: 16 * x0 - str 17 * x1 - c 18 * Returns: 19 * x0 - address of first occurrence of 'c' or 0 20 */ 21 SYM_FUNC_START_WEAK(strchr) 22 and w1, w1, #0xff 23 1: ldrb w2, [x0], #1 24 cmp w2, w1 25 ccmp w2, wzr, #4, ne 26 b.ne 1b 27 sub x0, x0, #1 28 cmp w2, w1 29 csel x0, x0, xzr, eq 30 ret 31 SYM_FUNC_END(strchr) 32 EXPORT_SYMBOL_NOKASAN(strchr) 33