code.delx.au - gnu-emacs/blob - src/m/alpha.h

   1 /* machine description file For the alpha chip.
   2    Copyright (C) 1994, 1997, 1999 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 1, 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, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 /* The following line tells the configuration script what sort of
  23    operating system this machine is likely to run.
  24    USUAL-OPSYS="note"
  25
  26 NOTE-START
  27 Use -opsystem=osf1
  28 NOTE-END
  29
  30 */
  31
  32 #define BITS_PER_LONG 64
  33 #define BITS_PER_EMACS_INT 64
  34 #ifndef _LP64
  35 #define _LP64
  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 /* Define WORD_MACHINE if addresses and such have
  49  * to be corrected before they can be used as byte counts.  */
  50
  51 /* #define WORD_MACHINE */
  52
  53 /* Now define a symbol for the cpu type, if your compiler
  54    does not define it automatically:
  55    Ones defined so far include vax, m68000, ns16000, pyramid,
  56    orion, tahoe, APOLLO and many others */
  57
  58 /* __alpha defined automatically */
  59
  60
  61 /* Use type EMACS_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 the type to use.  */
  67 #define EMACS_INT long
  68 #define EMACS_UINT unsigned long
  69 #define SPECIAL_EMACS_INT
  70
  71 /* Define EXPLICIT_SIGN_EXTEND if XINT must explicitly sign-extend
  72    the 24-bit bit field into an int.  In other words, if bit fields
  73    are always unsigned.
  74
  75    If you use NO_UNION_TYPE, this flag does not matter.  */
  76
  77 #define EXPLICIT_SIGN_EXTEND
  78
  79 /* Data type of load average, as read out of kmem.  */
  80
  81 #define LOAD_AVE_TYPE long
  82
  83 /* Convert that into an integer that is 100 for a load average of 1.0  */
  84
  85 #define LOAD_AVE_CVT(x) (int) (((double) (x)) * 100.0 / FSCALE)
  86
  87 /* Define CANNOT_DUMP on machines where unexec does not work.
  88    Then the function dump-emacs will not be defined
  89    and temacs will do (load "loadup") automatically unless told otherwise.  */
  90
  91 /* #define CANNOT_DUMP */
  92
  93 /* Define VIRT_ADDR_VARIES if the virtual addresses of
  94    pure and impure space as loaded can vary, and even their
  95    relative order cannot be relied on.
  96
  97    Otherwise Emacs assumes that text space precedes data space,
  98    numerically.  */
  99
 100 /* #define VIRT_ADDR_VARIES */
 101
 102 /* Define C_ALLOCA if this machine does not support a true alloca
 103    and the one written in C should be used instead.
 104    Define HAVE_ALLOCA to say that the system provides a properly
 105    working alloca function and it should be used.
 106    Define neither one if an assembler-language alloca
 107    in the file alloca.s should be used.  */
 108
 109 #define HAVE_ALLOCA
 110
 111 /* GNU malloc and the relocating allocator do not work together
 112    with X.   [Who wrote that?]  */
 113
 114 /* May 1995: reportedly [Rainer Schoepf <schoepf@uni-mainz.de>] both the
 115    system and the gnu malloc system work with "alpha-dec-osf3.0" and
 116    "alpha-dec-osf3.2".  */
 117
 118 /* May 1995: it seems to me [Morten Welinder <terra@diku.dk>] that both
 119    mallocs work with "alpha-dec-osf2.0", but I daren't break anything
 120    right now.  Feel free to play if you want.  */
 121
 122 /* #define SYSTEM_MALLOC */
 123
 124 /* Define NO_REMAP if memory segmentation makes it not work well
 125    to change the boundary between the text section and data section
 126    when Emacs is dumped.  If you define this, the preloaded Lisp
 127    code will not be sharable; but that's better than failing completely.  */
 128
 129 #define NO_REMAP
 130
 131 /* Some really obscure 4.2-based systems (like Sequent DYNIX)
 132  * do not support asynchronous I/O (using SIGIO) on sockets,
 133  * even though it works fine on tty's.  If you have one of
 134  * these systems, define the following, and then use it in
 135  * config.h (or elsewhere) to decide when (not) to use SIGIO.
 136  *
 137  * You'd think this would go in an operating-system description file,
 138  * but since it only occurs on some, but not all, BSD systems, the
 139  * reasonable place to select for it is in the machine description
 140  * file.
 141  */
 142
 143 /* #define NO_SOCK_SIGIO */
 144
 145
 146 #ifdef __ELF__
 147 /* With ELF, make sure that all common symbols get allocated to in the
 148    data section.  Otherwise, the dump of temacs may miss variables in
 149    the shared library that have been initialized.  For example, with
 150    GNU libc, __malloc_initialized would normally be resolved to the
 151    shared library's .bss section, which is fatal.  */
 152 # ifdef __GNUC__
 153 #  define C_SWITCH_MACHINE      -fno-common
 154 # else
 155 #  error What gives?  Fix me if DEC Unix supports ELF now.
 156 # endif
 157 #endif
 158
 159 #if defined(__OpenBSD__)
 160 #define ORDINARY_LINK
 161 #endif
 162
 163 #ifdef __ELF__
 164 #undef UNEXEC
 165 #define UNEXEC unexelf.o
 166 #endif
 167
 168 #ifndef __ELF__
 169
 170 /* Describe layout of the address space in an executing process.  */
 171
 172 #define TEXT_START    0x120000000
 173 #define DATA_START    0x140000000
 174
 175 /* This is necessary for mem-limits.h, so that start_of_data gives
 176    the correct value */
 177
 178 #define DATA_SEG_BITS 0x140000000
 179
 180 /* The program to be used for unexec. */
 181
 182 #define UNEXEC unexalpha.o
 183
 184 #endif /* notdef __ELF__ */
 185
 186 #ifdef OSF1
 187 #define ORDINARY_LINK
 188
 189 /* Some systems seem to have this, others don't.  */
 190 #ifdef HAVE_LIBDNET
 191 #define LIBS_MACHINE -ldnet
 192 #else
 193 #define LIBS_MACHINE -ldnet_stub
 194 #endif
 195 #endif /* OSF1 */
 196
 197 #if 0 /* Rainer Schoepf <schoepf@uni-mainz.de> says this loses with X11R6
 198          since it has only shared libraries.  */
 199 #ifndef __GNUC__
 200 /* This apparently is for the system ld as opposed to Gnu ld.  */
 201 #ifdef OSF1
 202 #define LD_SWITCH_MACHINE      -non_shared
 203 #endif
 204 #endif
 205 #endif /* 0 */
 206
 207 #ifdef OSF1
 208 #define LIBS_DEBUG
 209 #define START_FILES pre-crt0.o
 210 #endif
 211
 212 #if defined (LINUX) && __GNU_LIBRARY__ - 0 < 6
 213 /* This controls a conditional in main.  */
 214 #define LINUX_SBRK_BUG
 215 #endif
 216
 217
 218 #define PNTR_COMPARISON_TYPE unsigned long
 219
 220 /* On the 64 bit architecture, we can use 60 bits for addresses */
 221
 222 #define VALBITS         60
 223
 224
 225 /* This definition of MARKBIT is necessary because of the comparison of
 226    ARRAY_MARK_FLAG and MARKBIT in an #if in lisp.h, which cpp doesn't like. */
 227
 228 #define MARKBIT         0x8000000000000000L
 229
 230
 231 /* Define XINT and XUINT so that they can take arguments of type int */
 232
 233 #define XINT(a)  (((long) (a) << (BITS_PER_LONG - VALBITS)) >> (BITS_PER_LONG - VALBITS))
 234 #define XUINT(a) ((long) (a) & VALMASK)
 235
 236 /* Define XPNTR to avoid or'ing with DATA_SEG_BITS */
 237
 238 #define XPNTR(a) XUINT (a)
 239
 240 #ifndef NOT_C_CODE
 241 /* We need these because pointers are larger than the default ints.  */
 242 #if !defined(__NetBSD__) && !defined(__OpenBSD__)
 243 #include <alloca.h>
 244 #endif
 245
 246 /* Hack alert!  For reasons unknown to mankind the string.h file insists
 247    on defining bcopy etc. as taking char pointers as arguments.  With
 248    Emacs this produces an endless amount of warning which are harmless,
 249    but tends to flood the real errors.  This hack works around this problem
 250    by not prototyping.  */
 251 #define bcopy string_h_bcopy
 252 #define bzero string_h_bzero
 253 #define bcmp  string_h_bcmp
 254 #include <string.h>
 255 #undef bcopy
 256 #undef bzero
 257 #undef bcmp
 258
 259 extern long *xmalloc (), *xrealloc ();
 260
 261 #ifdef REL_ALLOC
 262 #ifndef _MALLOC_INTERNAL
 263 /* "char *" because ralloc.c defines it that way.  gmalloc.c thinks it
 264    is allowed to prototype these as "void *" so we don't prototype in
 265    that case.  You're right: it stinks!  */
 266 extern char *r_alloc (), *r_re_alloc ();
 267 extern void r_alloc_free ();
 268 #endif /* not _MALLOC_INTERNAL */
 269 #endif /* REL_ALLOC */
 270
 271 #endif /* not NOT_C_CODE */
 272
 273 #ifdef OSF1
 274 #define PTY_ITERATION           for (i = 0; i < 1; i++) /* ick */
 275 #define PTY_NAME_SPRINTF        /* none */
 276 #define PTY_TTY_NAME_SPRINTF    /* none */
 277 #define PTY_OPEN                                        \
 278   do                                                    \
 279     {                                                   \
 280       int dummy;                                        \
 281       SIGMASKTYPE mask;                                 \
 282       mask = sigblock (sigmask (SIGCHLD));              \
 283       if (-1 == openpty (&fd, &dummy, pty_name, 0, 0))  \
 284         fd = -1;                                        \
 285       sigsetmask (mask);                                \
 286       emacs_close (dummy);                              \
 287     }                                                   \
 288   while (0)
 289 #endif
 290
 291 /* On the Alpha it's best to avoid including TERMIO since struct
 292    termio and struct termios are mutually incompatible.  */
 293 #define NO_TERMIO
 294
 295 #if defined (LINUX) || defined (__NetBSD__) || defined (__OpenBSD__)
 296 # define TEXT_END ({ extern int _etext; &_etext; })
 297 # ifndef __ELF__
 298 #  define COFF
 299 #  define DATA_END ({ extern int _EDATA; &_EDATA; })
 300 # endif /* notdef __ELF__ */
 301 #endif
 302
 303 #if (defined (__NetBSD__) || defined (__OpenBSD__)) && defined (__ELF__)
 304 #define HAVE_TEXT_START
 305 #endif
 306
 307 /* Many Alpha implementations (e.g. gas 2.8) can't handle DBL_MIN:
 308    they generate code that uses a signaling NaN instead of DBL_MIN.
 309    Define DBL_MIN_REPLACEMENT to be the next value larger than DBL_MIN:
 310    this avoids the assembler bug.  */
 311 #define DBL_MIN_REPLACEMENT 2.2250738585072019e-308