reg_help.h   [plain text]


/*
 * Copyright (c) 2004, Apple Computer, Inc. All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission. 
 * 
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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/* Copyright (c) 1991 NeXT Computer, Inc.  All rights reserved.
 *
 *	File:	architecture/nrw/reg_help.h
 *	Author:	Mike DeMoney, NeXT Computer, Inc.
 *
 *	This header file defines cpp macros useful for defining
 *	machine register and doing machine-level operations.
 *
 * HISTORY
 * 23-Jan-91  Mike DeMoney (mike@next.com)
 *	Created.
 */

#ifndef	_NRW_REG_HELP_H_
#define	_NRW_REG_HELP_H_

/* Bitfield definition aid */
#define	BITS_WIDTH(msb, lsb)	((msb)-(lsb)+1)
#define	BIT_WIDTH(pos)		(1)	/* mostly to record the position */

/* Mask creation */
#define	MKMASK(width, offset)	(((unsigned)-1)>>(32-(width))<<(offset))
#define	BITSMASK(msb, lsb)	MKMASK(BITS_WIDTH(msb, lsb), lsb & 0x1f)
#define	BITMASK(pos)		MKMASK(BIT_WIDTH(pos), pos & 0x1f)

/* Register addresses */
#if	__ASSEMBLER__
# define	REG_ADDR(type, addr)	(addr)
#else	/* __ASSEMBLER__ */
# define	REG_ADDR(type, addr)	(*(volatile type *)(addr))
#endif	/* __ASSEMBLER__ */

/* Cast a register to be an unsigned */
#define	CONTENTS(foo)	(*(unsigned *) &(foo))

/* STRINGIFY -- perform all possible substitutions, then stringify */
#define	__STR(x)	#x		/* just a helper macro */
#define	STRINGIFY(x)	__STR(x)


#endif	/* _NRW_REG_HELP_H_ */