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/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2013 Huawei Ltd.
 * Author: Jiang Liu <liuj97@gmail.com>
 *
 * Based on arch/arm/include/asm/jump_label.h
 */
#ifndef __ASM_JUMP_LABEL_H
#define __ASM_JUMP_LABEL_H

#ifndef __ASSEMBLY__

#include <linux/types.h>
#include <asm/insn.h>

#define JUMP_LABEL_NOP_SIZE		AARCH64_INSN_SIZE

#define JUMP_TABLE_ENTRY(key, label)			\
	".pushsection	__jump_table, \"aw\"\n\t"	\
	".align		3\n\t"				\
	".long		1b - ., %l["#label"] - .\n\t"	\
	".quad		%c0 - .\n\t"			\
	".popsection\n\t"				\
	:  :  "i"(key) :  : label

static __always_inline bool arch_static_branch(struct static_key * const key,
					       const bool branch)
{
	char *k = &((char *)key)[branch];

	asm goto(
		"1:	nop					\n\t"
		JUMP_TABLE_ENTRY(k, l_yes)
		);

	return false;
l_yes:
	return true;
}

static __always_inline bool arch_static_branch_jump(struct static_key * const key,
						    const bool branch)
{
	char *k = &((char *)key)[branch];
	asm goto(
		"1:	b		%l[l_yes]		\n\t"
		JUMP_TABLE_ENTRY(k, l_yes)
		);
	return false;
l_yes:
	return true;
}

#endif  /* __ASSEMBLY__ */
#endif	/* __ASM_JUMP_LABEL_H */