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v0.5.1
https://github.com/torvalds/linux
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Tip revision: 48778464bb7d346b47157d21ffde2af6b2d39110 authored by Linus Torvalds on 21 June 2020, 22:45:29 UTC
Linux 5.8-rc2
Tip revision: 4877846
bitops.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * linux/arch/unicore32/include/asm/bitops.h
 *
 * Code specific to PKUnity SoC and UniCore ISA
 *
 * Copyright (C) 2001-2010 GUAN Xue-tao
 */

#ifndef __UNICORE_BITOPS_H__
#define __UNICORE_BITOPS_H__

#define _ASM_GENERIC_BITOPS_FLS_H_
#define _ASM_GENERIC_BITOPS___FLS_H_
#define _ASM_GENERIC_BITOPS_FFS_H_
#define _ASM_GENERIC_BITOPS___FFS_H_
/*
 * On UNICORE, those functions can be implemented around
 * the cntlz instruction for much better code efficiency.
 */

static inline int fls(unsigned int x)
{
	int ret;

	asm("cntlz\t%0, %1" : "=r" (ret) : "r" (x) : "cc");
	ret = 32 - ret;

	return ret;
}

#define __fls(x) (fls(x) - 1)
#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
#define __ffs(x) (ffs(x) - 1)

#include <asm-generic/bitops.h>

/* following definitions: to avoid using codes in lib/find_*.c */
#define find_next_bit		find_next_bit
#define find_next_zero_bit	find_next_zero_bit
#define find_first_bit		find_first_bit
#define find_first_zero_bit	find_first_zero_bit

#include <asm-generic/bitops/find.h>

#endif /* __UNICORE_BITOPS_H__ */
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