1 /* $OpenBSD: fpbits.h,v 1.6 2002/09/20 19:26:59 mickey Exp $ */ 2 /* 3 (c) Copyright 1986 HEWLETT-PACKARD COMPANY 4 To anyone who acknowledges that this file is provided "AS IS" 5 without any express or implied warranty: 6 permission to use, copy, modify, and distribute this file 7 for any purpose is hereby granted without fee, provided that 8 the above copyright notice and this notice appears in all 9 copies, and that the name of Hewlett-Packard Company not be 10 used in advertising or publicity pertaining to distribution 11 of the software without specific, written prior permission. 12 Hewlett-Packard Company makes no representations about the 13 suitability of this software for any purpose. 14 */ 15 /* @(#)fpbits.h: Revision: 1.6.88.1 Date: 93/12/07 15:06:21 */ 16 17 /* 18 * These macros are designed to be portable to all machines that have 19 * a wordsize greater than or equal to 32 bits that support the portable 20 * C compiler and the standard C preprocessor. Wordsize (default 32) 21 * and bitfield assignment (default left-to-right, unlike VAX, PDP-11) 22 * should be predefined using the constants HOSTWDSZ and BITFRL and 23 * the C compiler "-D" flag (e.g., -DHOSTWDSZ=36 -DBITFLR for the DEC-20). 24 * Note that the macro arguments assume that the integer being referenced 25 * is a 32-bit integer (right-justified on the 20) and that bit 0 is the 26 * most significant bit. 27 */ 28 29 #ifndef HOSTWDSZ 30 #define HOSTWDSZ 32 31 #endif 32 33 34 /*########################### Macros ######################################*/ 35 36 /*------------------------------------------------------------------------- 37 * NewDeclareBitField_Reference - Declare a structure similar to the simulator 38 * function "DeclBitfR" except its use is restricted to occur within a larger 39 * enclosing structure or union definition. This declaration is an unnamed 40 * structure with the argument, name, as the member name and the argument, 41 * uname, as the element name. 42 *----------------------------------------------------------------------- */ 43 #define Bitfield_extract(start, length, object) \ 44 ((object) >> (HOSTWDSZ - (start) - (length)) & \ 45 ((unsigned)-1 >> (HOSTWDSZ - (length)))) 46 47 #define Bitfield_signed_extract(start, length, object) \ 48 ((int)((object) << start) >> (HOSTWDSZ - (length))) 49 50 #define Bitfield_mask(start, len, object) \ 51 ((object) & (((unsigned)-1 >> (HOSTWDSZ-len)) << (HOSTWDSZ-start-len))) 52 53 #define Bitfield_deposit(value,start,len,object) object = \ 54 ((object) & ~(((unsigned)-1 >> (HOSTWDSZ-(len))) << (HOSTWDSZ-(start)-(len)))) | \ 55 (((value) & ((unsigned)-1 >> (HOSTWDSZ-(len)))) << (HOSTWDSZ-(start)-(len))) 56