xref: /openbmc/linux/arch/arm64/lib/strchr.S (revision a44e4f3a)
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 */
21WEAK(strchr)
22	and	w1, w1, #0xff
231:	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
31ENDPROC(strchr)
32EXPORT_SYMBOL_NOKASAN(strchr)
33