1/* 2 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23/* Copyright (c) 1991 NeXT Computer, Inc. All rights reserved. 24 * 25 * File: architecture/i386/reg_help.h 26 * Author: Mike DeMoney, NeXT Computer, Inc. 27 * Modified for i386 by: Bruce Martin, NeXT Computer, Inc. 28 * 29 * This header file defines cpp macros useful for defining 30 * machine register and doing machine-level operations. 31 * 32 * HISTORY 33 * 10-Mar-92 Bruce Martin (bmartin@next.com) 34 * Adapted to i386 35 * 23-Jan-91 Mike DeMoney (mike@next.com) 36 * Created. 37 */ 38 39#ifndef _ARCH_I386_REG_HELP_H_ 40#define _ARCH_I386_REG_HELP_H_ 41 42/* Bitfield definition aid */ 43#define BITS_WIDTH(msb, lsb) ((msb)-(lsb)+1) 44#define BIT_WIDTH(pos) (1) /* mostly to record the position */ 45 46/* Mask creation */ 47#define MKMASK(width, offset) (((unsigned)-1)>>(32-(width))<<(offset)) 48#define BITSMASK(msb, lsb) MKMASK(BITS_WIDTH(msb, lsb), lsb & 0x1f) 49#define BITMASK(pos) MKMASK(BIT_WIDTH(pos), pos & 0x1f) 50 51/* Register addresses */ 52#if __ASSEMBLER__ 53# define REG_ADDR(type, addr) (addr) 54#else /* __ASSEMBLER__ */ 55# define REG_ADDR(type, addr) (*(volatile type *)(addr)) 56#endif /* __ASSEMBLER__ */ 57 58/* Cast a register to be an unsigned */ 59#define CONTENTS(foo) (*(unsigned *) &(foo)) 60 61/* Stack pointer must always be a multiple of 4 */ 62#define STACK_INCR 4 63#define ROUND_FRAME(x) ((((unsigned)(x)) + STACK_INCR - 1) & ~(STACK_INCR-1)) 64 65/* STRINGIFY -- perform all possible substitutions, then stringify */ 66#define __STR(x) #x /* just a helper macro */ 67#define STRINGIFY(x) __STR(x) 68 69/* 70 * REG_PAIR_DEF -- define a register pair 71 * Register pairs are appropriately aligned to allow access via 72 * ld.d and st.d. 73 * 74 * Usage: 75 * struct foo { 76 * REG_PAIR_DEF( 77 * bar_t *, barp, 78 * afu_t, afu 79 * ); 80 * }; 81 * 82 * Access to individual entries of the pair is via the REG_PAIR 83 * macro (below). 84 */ 85#define REG_PAIR_DEF(type0, name0, type1, name1) \ 86 struct { \ 87 type0 name0 __attribute__(( aligned(8) )); \ 88 type1 name1; \ 89 } name0##_##name1 90 91/* 92 * REG_PAIR -- Macro to define names for accessing individual registers 93 * of register pairs. 94 * 95 * Usage: 96 * arg0 is first element of pair 97 * arg1 is second element of pair 98 * arg2 is desired element of pair 99 * eg: 100 * #define foo_barp REG_PAIR(barp, afu, afu) 101 */ 102#define REG_PAIR(name0, name1, the_name) \ 103 name0##_##name1.the_name 104 105#endif /* _ARCH_I386_REG_HELP_H_ */ 106