1 /* 2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_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. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 /* Copyright (c) 1991 NeXT Computer, Inc. All rights reserved. 29 * 30 * File: architecture/i386/reg_help.h 31 * Author: Mike DeMoney, NeXT Computer, Inc. 32 * Modified for i386 by: Bruce Martin, NeXT Computer, Inc. 33 * 34 * This header file defines cpp macros useful for defining 35 * machine register and doing machine-level operations. 36 * 37 * HISTORY 38 * 10-Mar-92 Bruce Martin ([email protected]) 39 * Adapted to i386 40 * 23-Jan-91 Mike DeMoney ([email protected]) 41 * Created. 42 */ 43 44 #ifndef _ARCH_I386_REG_HELP_H_ 45 #define _ARCH_I386_REG_HELP_H_ 46 47 /* Bitfield definition aid */ 48 #define BITS_WIDTH(msb, lsb) ((msb)-(lsb)+1) 49 #define BIT_WIDTH(pos) (1) /* mostly to record the position */ 50 51 /* Mask creation */ 52 #define MKMASK(width, offset) (((unsigned)-1)>>(32-(width))<<(offset)) 53 #define BITSMASK(msb, lsb) MKMASK(BITS_WIDTH(msb, lsb), lsb & 0x1f) 54 #define BITMASK(pos) MKMASK(BIT_WIDTH(pos), pos & 0x1f) 55 56 /* Register addresses */ 57 #if __ASSEMBLER__ 58 # define REG_ADDR(type, addr) (addr) 59 #else /* __ASSEMBLER__ */ 60 # define REG_ADDR(type, addr) (*(volatile type *)(addr)) 61 #endif /* __ASSEMBLER__ */ 62 63 /* Cast a register to be an unsigned */ 64 #define CONTENTS(foo) (*(unsigned *) &(foo)) 65 66 /* Stack pointer must always be a multiple of 4 */ 67 #define STACK_INCR 4 68 #define ROUND_FRAME(x) ((((unsigned)(x)) + STACK_INCR - 1) & ~(STACK_INCR-1)) 69 70 /* STRINGIFY -- perform all possible substitutions, then stringify */ 71 #define __STR(x) #x /* just a helper macro */ 72 #define STRINGIFY(x) __STR(x) 73 74 /* 75 * REG_PAIR_DEF -- define a register pair 76 * Register pairs are appropriately aligned to allow access via 77 * ld.d and st.d. 78 * 79 * Usage: 80 * struct foo { 81 * REG_PAIR_DEF( 82 * bar_t *, barp, 83 * afu_t, afu 84 * ); 85 * }; 86 * 87 * Access to individual entries of the pair is via the REG_PAIR 88 * macro (below). 89 */ 90 #define REG_PAIR_DEF(type0, name0, type1, name1) \ 91 struct { \ 92 type0 name0 __attribute__(( aligned(8) )); \ 93 type1 name1; \ 94 } name0##_##name1 95 96 /* 97 * REG_PAIR -- Macro to define names for accessing individual registers 98 * of register pairs. 99 * 100 * Usage: 101 * arg0 is first element of pair 102 * arg1 is second element of pair 103 * arg2 is desired element of pair 104 * eg: 105 * #define foo_barp REG_PAIR(barp, afu, afu) 106 */ 107 #define REG_PAIR(name0, name1, the_name) \ 108 name0##_##name1.the_name 109 110 #endif /* _ARCH_I386_REG_HELP_H_ */ 111