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 2, 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 /* 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.  */
  56
  57 #ifndef elxsi
  58 #define elxsi
  59 #endif
  60
  61 /* Use type int rather than a union, to represent Lisp_Object */
  62 /* This is desirable for most machines.  */
  63
  64 #define NO_UNION_TYPE
  65
  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
  68    are always unsigned.
  69
  70    If you use NO_UNION_TYPE, this flag does not matter.  */
  71
  72 #define EXPLICIT_SIGN_EXTEND
  73
  74
  75 /* Name of kernel load average variable */
  76
  77 #undef LDAV_SYMBOL
  78 #define LDAV_SYMBOL "avenrun"
  79
  80 /* Data type of load average, as read out of kmem.  */
  81
  82 #define LOAD_AVE_TYPE double
  83
  84 /* Convert that into an integer that is 100 for a load average of 1.0  */
  85
  86 #define LOAD_AVE_CVT(x) (int) ((x) * 100.0)
  87
  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.
  91
  92    Earlier versions couldn't dump.
  93    Changes for 12.0 release are in 19.1.
  94    Dumping should work now.  */
  95
  96 /* #define CANNOT_DUMP */
  97
  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.
 101
 102    Otherwise Emacs assumes that text space precedes data space,
 103    numerically.  */
 104
 105 /* #define VIRT_ADDR_VARIES */
 106
 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.  */
 113
 114 #define C_ALLOCA
 115 /*#define HAVE_ALLOCA */
 116
 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.  */
 121 /*#define NO_REMAP*/
 122
 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
 126
 127 /* Address of start of text segment as loaded.  */
 128
 129 #define TEXT_START      0x800
 130
 131 /* Tell crt0.c not to define environ.  */
 132
 133 #define DONT_NEED_ENVIRON
 134
 135 /* The elxsi has no debugger, so might as well optimize instead
 136    of trying to make a symbol table.  */
 137
 138 #define C_DEBUG_SWITCH -O
 139
 140 /* Elxsi uses COFF under both Sys V and BSD environments */
 141
 142 #define COFF
 143
 144 #define ADJUST_EXEC_HEADER {\
 145 extern int _init_brk;\
 146 _init_brk = bss_start;\
 147 }