strrchr.S

 1/* SPDX-License-Identifier: GPL-2.0-only */
 2/*
 3 * Based on arch/arm/lib/strrchr.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 last occurrence of a character in a string.
14 *
15 * Parameters:
16 *	x0 - str
17 *	x1 - c
18 * Returns:
19 *	x0 - address of last occurrence of 'c' or 0
20 */
21SYM_FUNC_START(__pi_strrchr)
22	mov	x3, #0
23	and	w1, w1, #0xff
241:	ldrb	w2, [x0], #1
25	cbz	w2, 2f
26	cmp	w2, w1
27	b.ne	1b
28	sub	x3, x0, #1
29	b	1b
302:	mov	x0, x3
31	ret
32SYM_FUNC_END(__pi_strrchr)
33SYM_FUNC_ALIAS_WEAK(strrchr, __pi_strrchr)
34EXPORT_SYMBOL_NOKASAN(strrchr)