src/m/aviion.h

   1 /* machine description file for Data General AViiON.
   2    Copyright (C) 1985, 1986, 1991 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21 /* The following three symbols give information on
  22  the size of various data types.  */
  23
  24 #define SHORTBITS 16            /* Number of bits in a short */
  25
  26 #define INTBITS 32              /* Number of bits in an int */
  27
  28 #define LONGBITS 32             /* Number of bits in a long */
  29
  30 /* Define BIG_ENDIAN iff lowest-numbered byte in a word
  31    is the most significant byte.  */
  32
  33 #define BIG_ENDIAN
  34
  35 /* Define NO_ARG_ARRAY if you cannot take the address of the first of a
  36  * group of arguments and treat it as an array of the arguments.  */
  37
  38 #define NO_ARG_ARRAY
  39
  40 /* Define WORD_MACHINE if addresses and such have
  41  * to be corrected before they can be used as byte counts.  */
  42
  43 #define WORD_MACHINE
  44
  45 /* Define DATA_SEG_BITS if pointers need to be corrected with
  46    a segment field.  */
  47
  48 #ifdef FIX_ADDRESS
  49 #define DATA_SEG_BITS 0xef000000
  50 #endif
  51
  52 /* Now define a symbol for the cpu type, if your compiler
  53    does not define it automatically:
  54    Ones defined so far include vax, m68000, ns16000, pyramid,
  55    orion, tahoe, APOLLO and many others */
  56
  57 #ifndef m88k
  58 #define m88k
  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 /* Data type of load average, as read out of kmem.  */
  75
  76 /* #define LOAD_AVE_TYPE long */
  77
  78 /* Convert that into an integer that is 100 for a load average of 1.0  */
  79
  80 /* #define LOAD_AVE_CVT(x) (int) (((double) (x)) * 100.0 / FSCALE) */
  81
  82 /* Define CANNOT_DUMP on machines where unexec does not work.
  83    Then the function dump-emacs will not be defined
  84    and temacs will do (load "loadup") automatically unless told otherwise.  */
  85
  86 /* #define CANNOT_DUMP */
  87
  88 /* Define VIRT_ADDR_VARIES if the virtual addresses of
  89    pure and impure space as loaded can vary, and even their
  90    relative order cannot be relied on.
  91
  92    Otherwise Emacs assumes that text space precedes data space,
  93    numerically.  */
  94
  95 /* #define VIRT_ADDR_VARIES */
  96
  97 /* Define C_ALLOCA if this machine does not support a true alloca
  98    and the one written in C should be used instead.
  99    Define HAVE_ALLOCA to say that the system provides a properly
 100    working alloca function and it should be used.
 101    Define neither one if an assembler-language alloca
 102    in the file alloca.s should be used.  */
 103
 104 /* #define C_ALLOCA */
 105 #define HAVE_ALLOCA
 106 #define alloca(x) __builtin_alloca(x)
 107
 108 /* Define NO_REMAP if memory segmentation makes it not work well
 109    to change the boundary between the text section and data section
 110    when Emacs is dumped.  If you define this, the preloaded Lisp
 111    code will not be sharable; but that's better than failing completely.  */
 112
 113 #define NO_REMAP
 114
 115 /* Use 26 bits instead of 24 for internal pointer values */
 116
 117 #define VALBITS 26
 118 #define GCTYPEBITS 5
 119
 120 /* Define ADDR_CORRECT(ADDR) to be a macro to correct an int which is
 121    the bit pattern of a pointer to a byte into an int which is the
 122    number of a byte.
 123
 124    This macro has a default definition which is usually right.
 125    This default definition is a no-op on most machines (where a
 126    pointer looks like an int) but not on all machines. */
 127
 128 #define ADDR_CORRECT(ADDR) ((int)ADDR)
 129
 130 /* Cast pointers to this type to compare them. */
 131
 132 #define PNTR_COMPARISON_TYPE    void *
 133
 134 /* Some machines that use COFF executables require that each section
 135    start on a certain boundary *in the COFF file*.  Such machines should
 136    define SECTION_ALIGNMENT to a mask of the low-order bits that must be
 137    zero on such a boundary.  This mask is used to control padding between
 138    segments in the COFF file.
 139
 140    If SECTION_ALIGNMENT is not defined, the segments are written
 141    consecutively with no attempt at alignment.  This is right for
 142    unmodified system V.  */
 143
 144 #define SECTION_ALIGNMENT 0x7
 145