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, 2009, 2010  Free Software Foundation, Inc.
   4
   5 Author: Rainer Schoepf
   6 (according to authors.el)
   7
   8 This file is part of GNU Emacs.
   9
  10 GNU Emacs is free software: you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation, either version 3 of the License, or
  13 (at your option) any later version.
  14
  15 GNU Emacs is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23
  24 /* The following line tells the configuration script what sort of
  25    operating system this machine is likely to run.
  26    USUAL-OPSYS="note"
  27
  28 NOTE-START
  29 Use -opsystem=osf1
  30 NOTE-END
  31
  32 */
  33
  34 #ifndef _LP64
  35 #define _LP64                   /* This doesn't appear to be necessary
  36                                    on OSF 4/5  -- fx.  */
  37 #endif
  38
  39 /* Define WORDS_BIG_ENDIAN if lowest-numbered byte in a word
  40    is the most significant byte.  */
  41
  42 #undef WORDS_BIG_ENDIAN
  43
  44 /* Now define a symbol for the cpu type, if your compiler
  45    does not define it automatically.  */
  46
  47 /* __alpha defined automatically */
  48
  49
  50 /* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
  51    the 24-bit bit field into an int.  In other words, if bit fields
  52    are always unsigned.
  53
  54    This flag only matters if you use USE_LISP_UNION_TYPE.  */
  55
  56 #define EXPLICIT_SIGN_EXTEND
  57
  58 /* Data type of load average, as read out of kmem.  */
  59
  60 #define LOAD_AVE_TYPE long
  61
  62 /* Convert that into an integer that is 100 for a load average of 1.0  */
  63
  64 #define LOAD_AVE_CVT(x) (int) (((double) (x)) * 100.0 / FSCALE)
  65
  66 /* GNU malloc and the relocating allocator do not work together
  67    with X.   [Who wrote that?]  */
  68
  69 /* May 1995: reportedly [Rainer Schoepf <schoepf@uni-mainz.de>] both the
  70    system and the gnu malloc system work with "alpha-dec-osf3.0" and
  71    "alpha-dec-osf3.2".  */
  72
  73 /* May 1995: it seems to me [Morten Welinder <terra@diku.dk>] that both
  74    mallocs work with "alpha-dec-osf2.0", but I daren't break anything
  75    right now.  Feel free to play if you want.  */
  76
  77 /* #define SYSTEM_MALLOC */
  78
  79 #ifdef __ELF__
  80 /* With ELF, make sure that all common symbols get allocated to in the
  81    data section.  Otherwise, the dump of temacs may miss variables in
  82    the shared library that have been initialized.  For example, with
  83    GNU libc, __malloc_initialized would normally be resolved to the
  84    shared library's .bss section, which is fatal.  */
  85 # ifdef __GNUC__
  86 #  define C_SWITCH_MACHINE      -fno-common
  87 # else
  88 #  error What gives?  Fix me if DEC Unix supports ELF now.
  89 # endif
  90
  91 #undef UNEXEC
  92 #define UNEXEC unexelf.o
  93 #if !defined(GNU_LINUX) && !defined(__NetBSD__)
  94 #define DATA_START    0x140000000
  95 #endif
  96
  97 #if (defined (__NetBSD__) || defined (__OpenBSD__))
  98 #define HAVE_TEXT_START
  99 #endif
 100
 101 #else  /* not __ELF__ */
 102
 103 /* Describe layout of the address space in an executing process.  */
 104
 105 #define TEXT_START    0x120000000
 106 #define DATA_START    0x140000000
 107
 108 /* The program to be used for unexec. */
 109
 110 #define UNEXEC unexalpha.o
 111
 112 #endif /* __ELF__ */
 113
 114 /* On the Alpha it's best to avoid including TERMIO since struct
 115    termio and struct termios are mutually incompatible.  */
 116 #define NO_TERMIO
 117
 118 #if defined (GNU_LINUX) || defined (__NetBSD__) || defined (__OpenBSD__)
 119 # ifndef __ELF__
 120 #  define COFF
 121 # endif /* notdef __ELF__ */
 122 #endif
 123
 124 /* Many Alpha implementations (e.g. gas 2.8) can't handle DBL_MIN:
 125    they generate code that uses a signaling NaN instead of DBL_MIN.
 126    Define DBL_MIN_REPLACEMENT to be the next value larger than DBL_MIN:
 127    this avoids the assembler bug.  */
 128 #define DBL_MIN_REPLACEMENT 2.2250738585072019e-308
 129
 130 /* arch-tag: 978cb578-1e25-4a60-819b-adae0972aa78
 131    (do not change this comment) */