original_kernel/arch/arm64/lib/strrchr.S

35 lines
634 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Based on arch/arm/lib/strrchr.S
*
* Copyright (C) 1995-2000 Russell King
* Copyright (C) 2013 ARM Ltd.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
/*
* Find the last occurrence of a character in a string.
*
* Parameters:
* x0 - str
* x1 - c
* Returns:
* x0 - address of last occurrence of 'c' or 0
*/
SYM_FUNC_START(__pi_strrchr)
mov x3, #0
and w1, w1, #0xff
1: ldrb w2, [x0], #1
cbz w2, 2f
cmp w2, w1
b.ne 1b
sub x3, x0, #1
b 1b
2: mov x0, x3
ret
SYM_FUNC_END(__pi_strrchr)
SYM_FUNC_ALIAS_WEAK(strrchr, __pi_strrchr)
EXPORT_SYMBOL_NOKASAN(strrchr)