1/* machine description file For the alpha chip.
2   Copyright (C) 1994, 1997, 1999, 2001, 2002, 2003, 2004,
3                 2005, 2006, 2007  Free Software Foundation, Inc.
4
5This file is part of GNU Emacs.
6
7GNU Emacs is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2, or (at your option)
10any later version.
11
12GNU Emacs is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GNU Emacs; see the file COPYING.  If not, write to
19the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20Boston, MA 02110-1301, USA.  */
21
22
23/* The following line tells the configuration script what sort of
24   operating system this machine is likely to run.
25   USUAL-OPSYS="note"
26
27NOTE-START
28Use -opsystem=osf1
29NOTE-END
30
31*/
32
33#ifndef _LP64
34#define _LP64			/* This doesn't appear to be necessary
35				   on OSF 4/5  -- fx.  */
36#endif
37
38/* Define WORDS_BIG_ENDIAN iff lowest-numbered byte in a word
39   is the most significant byte.  */
40
41#undef WORDS_BIG_ENDIAN
42
43/* Define NO_ARG_ARRAY if you cannot take the address of the first of a
44 * group of arguments and treat it as an array of the arguments.  */
45
46#define NO_ARG_ARRAY
47
48/* Now define a symbol for the cpu type, if your compiler
49   does not define it automatically:
50   Ones defined so far include vax, m68000, ns16000, pyramid,
51   orion, tahoe, APOLLO and many others */
52
53/* __alpha defined automatically */
54
55
56/* Use type EMACS_INT rather than a union, to represent Lisp_Object */
57/* This is desirable for most machines.  */
58#define NO_UNION_TYPE
59
60/* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
61   the 24-bit bit field into an int.  In other words, if bit fields
62   are always unsigned.
63
64   If you use NO_UNION_TYPE, this flag does not matter.  */
65
66#define EXPLICIT_SIGN_EXTEND
67
68/* Data type of load average, as read out of kmem.  */
69
70#define LOAD_AVE_TYPE long
71
72/* Convert that into an integer that is 100 for a load average of 1.0  */
73
74#define LOAD_AVE_CVT(x) (int) (((double) (x)) * 100.0 / FSCALE)
75
76/* GNU malloc and the relocating allocator do not work together
77   with X.   [Who wrote that?]  */
78
79/* May 1995: reportedly [Rainer Schoepf <schoepf@uni-mainz.de>] both the
80   system and the gnu malloc system work with "alpha-dec-osf3.0" and
81   "alpha-dec-osf3.2".  */
82
83/* May 1995: it seems to me [Morten Welinder <terra@diku.dk>] that both
84   mallocs work with "alpha-dec-osf2.0", but I daren't break anything
85   right now.  Feel free to play if you want.  */
86
87/* #define SYSTEM_MALLOC */
88
89#ifdef __ELF__
90/* With ELF, make sure that all common symbols get allocated to in the
91   data section.  Otherwise, the dump of temacs may miss variables in
92   the shared library that have been initialized.  For example, with
93   GNU libc, __malloc_initialized would normally be resolved to the
94   shared library's .bss section, which is fatal.  */
95# ifdef __GNUC__
96#  define C_SWITCH_MACHINE	-fno-common
97# else
98#  error What gives?  Fix me if DEC Unix supports ELF now.
99# endif
100#endif
101
102#if defined(__OpenBSD__)
103#define ORDINARY_LINK
104#endif
105
106#ifdef __ELF__
107#undef UNEXEC
108#define UNEXEC unexelf.o
109#ifndef LINUX
110#define DATA_START    0x140000000
111#endif
112#endif
113
114#ifndef __ELF__
115
116/* Describe layout of the address space in an executing process.  */
117
118#define TEXT_START    0x120000000
119#define DATA_START    0x140000000
120
121/* The program to be used for unexec. */
122
123#define UNEXEC unexalpha.o
124
125#endif /* notdef __ELF__ */
126
127#if defined (LINUX) && __GNU_LIBRARY__ - 0 < 6
128/* This controls a conditional in main.  */
129#define LINUX_SBRK_BUG
130#endif
131
132/* On the Alpha it's best to avoid including TERMIO since struct
133   termio and struct termios are mutually incompatible.  */
134#define NO_TERMIO
135
136#if defined (LINUX) || defined (__NetBSD__) || defined (__OpenBSD__)
137# define TEXT_END ({ extern int _etext; &_etext; })
138# ifndef __ELF__
139#  define COFF
140#  define DATA_END ({ extern int _EDATA; &_EDATA; })
141# endif /* notdef __ELF__ */
142#endif
143
144#if (defined (__NetBSD__) || defined (__OpenBSD__)) && defined (__ELF__)
145#define HAVE_TEXT_START
146#endif
147
148/* Many Alpha implementations (e.g. gas 2.8) can't handle DBL_MIN:
149   they generate code that uses a signaling NaN instead of DBL_MIN.
150   Define DBL_MIN_REPLACEMENT to be the next value larger than DBL_MIN:
151   this avoids the assembler bug.  */
152#define DBL_MIN_REPLACEMENT 2.2250738585072019e-308
153
154/* arch-tag: 978cb578-1e25-4a60-819b-adae0972aa78
155   (do not change this comment) */
156