src/m/alpha.h

   1 /* machine description file For the alpha chip.
   2    Copyright (C) 1994, 1997, 1999, 2001, 2002, 2003, 2004, 2005, 2006,
   3                  2007, 2008  Free Software Foundation, Inc.
   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 3 of the License, or
  10 (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20
  21 /* The following line tells the configuration script what sort of
  22    operating system this machine is likely to run.
  23    USUAL-OPSYS="note"
  24
  25 NOTE-START
  26 Use -opsystem=osf1
  27 NOTE-END
  28
  29 */
  30
  31 #ifndef _LP64
  32 #define _LP64                   /* This doesn't appear to be necessary
  33                                    on OSF 4/5  -- fx.  */
  34 #endif
  35
  36 /* Define WORDS_BIG_ENDIAN if lowest-numbered byte in a word
  37    is the most significant byte.  */
  38
  39 #undef WORDS_BIG_ENDIAN
  40
  41 /* Define NO_ARG_ARRAY if you cannot take the address of the first of a
  42  * group of arguments and treat it as an array of the arguments.  */
  43
  44 #define NO_ARG_ARRAY
  45
  46 /* Now define a symbol for the cpu type, if your compiler
  47    does not define it automatically.  */
  48
  49 /* __alpha defined automatically */
  50
  51
  52 /* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
  53    the 24-bit bit field into an int.  In other words, if bit fields
  54    are always unsigned.
  55
  56    This flag only matters if you use USE_LISP_UNION_TYPE.  */
  57
  58 #define EXPLICIT_SIGN_EXTEND
  59
  60 /* Data type of load average, as read out of kmem.  */
  61
  62 #define LOAD_AVE_TYPE long
  63
  64 /* Convert that into an integer that is 100 for a load average of 1.0  */
  65
  66 #define LOAD_AVE_CVT(x) (int) (((double) (x)) * 100.0 / FSCALE)
  67
  68 /* GNU malloc and the relocating allocator do not work together
  69    with X.   [Who wrote that?]  */
  70
  71 /* May 1995: reportedly [Rainer Schoepf <schoepf@uni-mainz.de>] both the
  72    system and the gnu malloc system work with "alpha-dec-osf3.0" and
  73    "alpha-dec-osf3.2".  */
  74
  75 /* May 1995: it seems to me [Morten Welinder <terra@diku.dk>] that both
  76    mallocs work with "alpha-dec-osf2.0", but I daren't break anything
  77    right now.  Feel free to play if you want.  */
  78
  79 /* #define SYSTEM_MALLOC */
  80
  81 #ifdef __ELF__
  82 /* With ELF, make sure that all common symbols get allocated to in the
  83    data section.  Otherwise, the dump of temacs may miss variables in
  84    the shared library that have been initialized.  For example, with
  85    GNU libc, __malloc_initialized would normally be resolved to the
  86    shared library's .bss section, which is fatal.  */
  87 # ifdef __GNUC__
  88 #  define C_SWITCH_MACHINE      -fno-common
  89 # else
  90 #  error What gives?  Fix me if DEC Unix supports ELF now.
  91 # endif
  92
  93 #undef UNEXEC
  94 #define UNEXEC unexelf.o
  95 #ifndef GNU_LINUX
  96 #define DATA_START    0x140000000
  97 #endif
  98
  99 #if (defined (__NetBSD__) || defined (__OpenBSD__))
 100 #define HAVE_TEXT_START
 101 #endif
 102
 103 #else  /* not __ELF__ */
 104
 105 /* Describe layout of the address space in an executing process.  */
 106
 107 #define TEXT_START    0x120000000
 108 #define DATA_START    0x140000000
 109
 110 /* The program to be used for unexec. */
 111
 112 #define UNEXEC unexalpha.o
 113
 114 #endif /* __ELF__ */
 115
 116 #if defined (GNU_LINUX) && __GNU_LIBRARY__ - 0 < 6
 117 /* This controls a conditional in main.  */
 118 #define LINUX_SBRK_BUG
 119 #endif
 120
 121 /* On the Alpha it's best to avoid including TERMIO since struct
 122    termio and struct termios are mutually incompatible.  */
 123 #define NO_TERMIO
 124
 125 #if defined (GNU_LINUX) || defined (__NetBSD__) || defined (__OpenBSD__)
 126 # ifndef __ELF__
 127 #  define COFF
 128 # endif /* notdef __ELF__ */
 129 #endif
 130
 131 /* Many Alpha implementations (e.g. gas 2.8) can't handle DBL_MIN:
 132    they generate code that uses a signaling NaN instead of DBL_MIN.
 133    Define DBL_MIN_REPLACEMENT to be the next value larger than DBL_MIN:
 134    this avoids the assembler bug.  */
 135 #define DBL_MIN_REPLACEMENT 2.2250738585072019e-308
 136
 137 /* arch-tag: 978cb578-1e25-4a60-819b-adae0972aa78
 138    (do not change this comment) */