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/*
 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
 *
 * This file is part of nios2sim-ng.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#ifndef _BITS_H_
#define _BITS_H_

#define BIT_MASK_FILL(n)	(((n) == 64) ? ~0ULL : ((1ULL << (n))-1))
#define BIT_MASK(n)		(1UL << ((n) % 32))
#define BIT_UINT32(n)		((n) / 32)

/**
 * Sets a bit in memory.
 */
static inline void set_bit(unsigned int nr, uint32_t *addr)
{
	uint32_t mask = BIT_MASK(nr);
	uint32_t *p = addr + BIT_UINT32(nr);

	*p |= mask;
}

/**
 * Clears a bit in memory.
 */
static inline void clear_bit(unsigned int nr, uint32_t *addr)
{
	uint32_t mask = BIT_MASK(nr);
	uint32_t *p = addr + BIT_UINT32(nr);

	*p &= ~mask;
}

#endif /* _BITS_H_ */