mirror of https://gitee.com/openkylin/linux.git
35 lines
562 B
ArmAsm
35 lines
562 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Based on arch/arm/lib/memchr.S
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*
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* Copyright (C) 1995-2000 Russell King
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* Copyright (C) 2013 ARM Ltd.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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/*
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* Find a character in an area of memory.
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*
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* Parameters:
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* x0 - buf
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* x1 - c
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* x2 - n
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* Returns:
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* x0 - address of first occurrence of 'c' or 0
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*/
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WEAK(memchr)
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and w1, w1, #0xff
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1: subs x2, x2, #1
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b.mi 2f
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ldrb w3, [x0], #1
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cmp w3, w1
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b.ne 1b
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sub x0, x0, #1
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ret
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2: mov x0, #0
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ret
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ENDPIPROC(memchr)
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EXPORT_SYMBOL_NOKASAN(memchr)
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