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, Inc., 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 /* The following line tells the configuration script what sort of
  23    operating system this machine is likely to run.
  24    USUAL-OPSYS="usg5-2"  */
  25
  26 /* This file was modified by Matt Crawford <matt@tank.uchicago.edu>
  27    to work under Elxsi's 12.0 release of BSD unix. */
  28
  29 /* Define WORDS_BIG_ENDIAN iff lowest-numbered byte in a word
  30    is the most significant byte.  */
  31
  32 #undef WORDS_BIG_ENDIAN
  33
  34 /* Define NO_ARG_ARRAY if you cannot take the address of the first of a
  35  * group of arguments and treat it as an array of the arguments.  */
  36
  37 /*#define NO_ARG_ARRAY */
  38
  39 /* Define WORD_MACHINE if addresses and such have
  40  * to be corrected before they can be used as byte counts.  */
  41
  42 /*#define WORD_MACHINE */
  43
  44 /* Now define a symbol for the cpu type, if your compiler
  45    does not define it automatically:
  46    vax, m68000, ns16000, pyramid, orion, tahoe and APOLLO
  47    are the ones defined so far.  */
  48
  49 #ifndef elxsi
  50 #define elxsi
  51 #endif
  52
  53 /* Use type int rather than a union, to represent Lisp_Object */
  54 /* This is desirable for most machines.  */
  55
  56 #define NO_UNION_TYPE
  57
  58 /* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
  59    the 24-bit bit field into an int.  In other words, if bit fields
  60    are always unsigned.
  61
  62    If you use NO_UNION_TYPE, this flag does not matter.  */
  63
  64 #define EXPLICIT_SIGN_EXTEND
  65
  66
  67 /* Name of kernel load average variable */
  68
  69 #undef LDAV_SYMBOL
  70 #define LDAV_SYMBOL "avenrun"
  71
  72 /* Data type of load average, as read out of kmem.  */
  73
  74 #define LOAD_AVE_TYPE double
  75
  76 /* Convert that into an integer that is 100 for a load average of 1.0  */
  77
  78 #define LOAD_AVE_CVT(x) (int) ((x) * 100.0)
  79
  80 /* Define CANNOT_DUMP on machines where unexec does not work.
  81    Then the function dump-emacs will not be defined
  82    and temacs will do (load "loadup") automatically unless told otherwise.
  83
  84    Earlier versions couldn't dump.
  85    Changes for 12.0 release are in 19.1.
  86    Dumping should work now.  */
  87
  88 /* #define CANNOT_DUMP */
  89
  90 /* Define VIRT_ADDR_VARIES if the virtual addresses of
  91    pure and impure space as loaded can vary, and even their
  92    relative order cannot be relied on.
  93
  94    Otherwise Emacs assumes that text space precedes data space,
  95    numerically.  */
  96
  97 /* #define VIRT_ADDR_VARIES */
  98
  99 /* Define C_ALLOCA if this machine does not support a true alloca
 100    and the one written in C should be used instead.
 101    Define HAVE_ALLOCA to say that the system provides a properly
 102    working alloca function and it should be used.
 103    Define neither one if an assembler-language alloca
 104    in the file alloca.s should be used.  */
 105
 106 #define C_ALLOCA
 107 /*#define HAVE_ALLOCA */
 108
 109 /* Define NO_REMAP if memory segmentation makes it not work well
 110    to change the boundary between the text section and data section
 111    when Emacs is dumped.  If you define this, the preloaded Lisp
 112    code will not be sharable; but that's better than failing completely.  */
 113 /*#define NO_REMAP*/
 114
 115 /* This is a guess for an alternate solution to whatever
 116    problem motivated defining _sobuf in sysdep,c with extern char *_sobuf.  */
 117 #define _sobuf xsobuf
 118
 119 /* Address of start of text segment as loaded.  */
 120
 121 #define TEXT_START      0x800
 122
 123 /* Tell crt0.c not to define environ.  */
 124
 125 #define DONT_NEED_ENVIRON
 126
 127 /* The elxsi has no debugger, so might as well optimize instead
 128    of trying to make a symbol table.  */
 129
 130 #define C_DEBUG_SWITCH -O
 131
 132 /* Elxsi uses COFF under both Sys V and BSD environments */
 133
 134 #define COFF
 135
 136 #define ADJUST_EXEC_HEADER {\
 137 extern int _init_brk;\
 138 _init_brk = bss_start;\
 139 }