src/m/elxsi.h

   1 /* machine description file for Elxsi machine (running enix).
   2    Copyright (C) 1986, 1992 Free Software Foundation, Inc.
   3    Adapted by John Salmon
   4
   5 This file is part of GNU Emacs.
   6
   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 1, or (at your option)
  10 any later version.
  11
  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.
  16
  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.  */
  20
  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"  */
  24
  25 /* This file was modified by Matt Crawford <matt@tank.uchicago.edu>
  26    to work under Elxsi's 12.0 release of BSD unix. */
  27
  28 /* The following three symbols give information on
  29  the size of various data types.  */
  30
  31 #define SHORTBITS 16            /* Number of bits in a short */
  32
  33 #define INTBITS 32              /* Number of bits in an int */
  34
  35 #define LONGBITS 32             /* Number of bits in a long */
  36
  37 /* Define BIG_ENDIAN iff lowest-numbered byte in a word
  38    is the most significant byte.  */
  39
  40 /*#define BIG_ENDIAN*/
  41
  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.  */
  44
  45 /*#define NO_ARG_ARRAY */
  46
  47 /* Define WORD_MACHINE if addresses and such have
  48  * to be corrected before they can be used as byte counts.  */
  49
  50 /*#define WORD_MACHINE */
  51
  52 /* Define how to take a char and sign-extend into an int.
  53    On machines where char is signed, this is a no-op.  */
  54
  55 #define SIGN_EXTEND_CHAR(c) ((int)c)
  56
  57 /* Now define a symbol for the cpu type, if your compiler
  58    does not define it automatically:
  59    vax, m68000, ns16000, pyramid, orion, tahoe and APOLLO
  60    are the ones defined so far.  */
  61
  62 #ifndef elxsi
  63 #define elxsi
  64 #endif
  65
  66 /* Use type int rather than a union, to represent Lisp_Object */
  67 /* This is desirable for most machines.  */
  68
  69 #define NO_UNION_TYPE
  70
  71 /* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
  72    the 24-bit bit field into an int.  In other words, if bit fields
  73    are always unsigned.
  74
  75    If you use NO_UNION_TYPE, this flag does not matter.  */
  76
  77 #define EXPLICIT_SIGN_EXTEND
  78
  79
  80 /* Name of kernel load average variable */
  81
  82 #undef LDAV_SYMBOL
  83 #define LDAV_SYMBOL "avenrun"
  84
  85 /* Data type of load average, as read out of kmem.  */
  86
  87 #define LOAD_AVE_TYPE double
  88
  89 /* Convert that into an integer that is 100 for a load average of 1.0  */
  90
  91 #define LOAD_AVE_CVT(x) (int) ((x) * 100.0)
  92
  93 /* Define CANNOT_DUMP on machines where unexec does not work.
  94    Then the function dump-emacs will not be defined
  95    and temacs will do (load "loadup") automatically unless told otherwise.
  96
  97    Earlier versions couldn't dump.
  98    Changes for 12.0 release are in 19.1.
  99    Dumping should work now.  */
 100
 101 /* #define CANNOT_DUMP */
 102
 103 /* Define VIRT_ADDR_VARIES if the virtual addresses of
 104    pure and impure space as loaded can vary, and even their
 105    relative order cannot be relied on.
 106
 107    Otherwise Emacs assumes that text space precedes data space,
 108    numerically.  */
 109
 110 /* #define VIRT_ADDR_VARIES */
 111
 112 /* Define C_ALLOCA if this machine does not support a true alloca
 113    and the one written in C should be used instead.
 114    Define HAVE_ALLOCA to say that the system provides a properly
 115    working alloca function and it should be used.
 116    Define neither one if an assembler-language alloca
 117    in the file alloca.s should be used.  */
 118
 119 #define C_ALLOCA
 120 /*#define HAVE_ALLOCA */
 121
 122 /* Define NO_REMAP if memory segmentation makes it not work well
 123    to change the boundary between the text section and data section
 124    when Emacs is dumped.  If you define this, the preloaded Lisp
 125    code will not be sharable; but that's better than failing completely.  */
 126 /*#define NO_REMAP*/
 127
 128 /* This is a guess for an alternate solution to whatever
 129    problem motivated defining _sobuf in sysdep,c with extern char *_sobuf.  */
 130 #define _sobuf xsobuf
 131
 132 /* Address of start of text segment as loaded.  */
 133
 134 #define TEXT_START      0x800
 135
 136 /* Tell crt0.c not to define environ.  */
 137
 138 #define DONT_NEED_ENVIRON
 139
 140 /* The elxsi has no debugger, so might as well optimize instead
 141    of trying to make a symbol table.  */
 142
 143 #define C_DEBUG_SWITCH -O
 144
 145 /* Elxsi uses COFF under both Sys V and BSD environments */
 146
 147 #define COFF
 148
 149 #define ADJUST_EXEC_HEADER {\
 150 extern int _init_brk;\
 151 _init_brk = bss_start;\
 152 }