1 /* machine description file for Elxsi machine (running enix).
2 Copyright (C) 1986, 1992 Free Software Foundation, Inc.
5 This file is part of GNU Emacs.
7 GNU Emacs is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs; see the file COPYING. If not, write to
19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* The following line tells the configuration script what sort of
22 operating system this machine is likely to run.
23 USUAL-OPSYS="usg5-2" */
25 /* This file was modified by Matt Crawford <matt@tank.uchicago.edu>
26 to work under Elxsi's 12.0 release of BSD unix. */
28 /* The following three symbols give information on
29 the size of various data types. */
31 #define SHORTBITS 16 /* Number of bits in a short */
33 #define INTBITS 32 /* Number of bits in an int */
35 #define LONGBITS 32 /* Number of bits in a long */
37 /* Define BIG_ENDIAN iff lowest-numbered byte in a word
38 is the most significant byte. */
40 /*#define BIG_ENDIAN*/
42 /* Define NO_ARG_ARRAY if you cannot take the address of the first of a
43 * group of arguments and treat it as an array of the arguments. */
45 /*#define NO_ARG_ARRAY */
47 /* Define WORD_MACHINE if addresses and such have
48 * to be corrected before they can be used as byte counts. */
50 /*#define WORD_MACHINE */
52 /* Now define a symbol for the cpu type, if your compiler
53 does not define it automatically:
54 vax, m68000, ns16000, pyramid, orion, tahoe and APOLLO
55 are the ones defined so far. */
61 /* Use type int rather than a union, to represent Lisp_Object */
62 /* This is desirable for most machines. */
66 /* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
67 the 24-bit bit field into an int. In other words, if bit fields
70 If you use NO_UNION_TYPE, this flag does not matter. */
72 #define EXPLICIT_SIGN_EXTEND
75 /* Name of kernel load average variable */
78 #define LDAV_SYMBOL "avenrun"
80 /* Data type of load average, as read out of kmem. */
82 #define LOAD_AVE_TYPE double
84 /* Convert that into an integer that is 100 for a load average of 1.0 */
86 #define LOAD_AVE_CVT(x) (int) ((x) * 100.0)
88 /* Define CANNOT_DUMP on machines where unexec does not work.
89 Then the function dump-emacs will not be defined
90 and temacs will do (load "loadup") automatically unless told otherwise.
92 Earlier versions couldn't dump.
93 Changes for 12.0 release are in 19.1.
94 Dumping should work now. */
96 /* #define CANNOT_DUMP */
98 /* Define VIRT_ADDR_VARIES if the virtual addresses of
99 pure and impure space as loaded can vary, and even their
100 relative order cannot be relied on.
102 Otherwise Emacs assumes that text space precedes data space,
105 /* #define VIRT_ADDR_VARIES */
107 /* Define C_ALLOCA if this machine does not support a true alloca
108 and the one written in C should be used instead.
109 Define HAVE_ALLOCA to say that the system provides a properly
110 working alloca function and it should be used.
111 Define neither one if an assembler-language alloca
112 in the file alloca.s should be used. */
115 /*#define HAVE_ALLOCA */
117 /* Define NO_REMAP if memory segmentation makes it not work well
118 to change the boundary between the text section and data section
119 when Emacs is dumped. If you define this, the preloaded Lisp
120 code will not be sharable; but that's better than failing completely. */
123 /* This is a guess for an alternate solution to whatever
124 problem motivated defining _sobuf in sysdep,c with extern char *_sobuf. */
125 #define _sobuf xsobuf
127 /* Address of start of text segment as loaded. */
129 #define TEXT_START 0x800
131 /* Tell crt0.c not to define environ. */
133 #define DONT_NEED_ENVIRON
135 /* The elxsi has no debugger, so might as well optimize instead
136 of trying to make a symbol table. */
138 #define C_DEBUG_SWITCH -O
140 /* Elxsi uses COFF under both Sys V and BSD environments */
144 #define ADJUST_EXEC_HEADER {\
145 extern int _init_brk;\
146 _init_brk = bss_start;\