WSL2-Linux-Kernel/arch/arm64/lib/strchr.S

33 строки
596 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Based on arch/arm/lib/strchr.S
*
* Copyright (C) 1995-2000 Russell King
* Copyright (C) 2013 ARM Ltd.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
/*
* Find the first occurrence of a character in a string.
*
* Parameters:
* x0 - str
* x1 - c
* Returns:
* x0 - address of first occurrence of 'c' or 0
*/
SYM_FUNC_START_WEAK(strchr)
and w1, w1, #0xff
1: ldrb w2, [x0], #1
cmp w2, w1
ccmp w2, wzr, #4, ne
b.ne 1b
sub x0, x0, #1
cmp w2, w1
csel x0, x0, xzr, eq
ret
SYM_FUNC_END(strchr)
EXPORT_SYMBOL_NOKASAN(strchr)