bfd/mmo.c

   1 /* BFD back-end for mmo objects (MMIX-specific object-format).
   2    Copyright 2001, 2002, 2003, 2004, 2005
   3    Free Software Foundation, Inc.
   4    Written by Hans-Peter Nilsson (hp@bitrange.com).
   5    Infrastructure and other bits originally copied from srec.c and
   6    binary.c.
   7
   8 This file is part of BFD, the Binary File Descriptor library.
   9
  10 This program 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 2 of the License, or
  13 (at your option) any later version.
  14
  15 This program 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 this program; if not, write to the Free Software
  22 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  23
  24 /*
  25 SECTION
  26         mmo backend
  27
  28         The mmo object format is used exclusively together with Professor
  29         Donald E.@: Knuth's educational 64-bit processor MMIX.  The simulator
  30         @command{mmix} which is available at
  31         @url{http://www-cs-faculty.stanford.edu/~knuth/programs/mmix.tar.gz}
  32         understands this format.  That package also includes a combined
  33         assembler and linker called @command{mmixal}.  The mmo format has
  34         no advantages feature-wise compared to e.g. ELF.  It is a simple
  35         non-relocatable object format with no support for archives or
  36         debugging information, except for symbol value information and
  37         line numbers (which is not yet implemented in BFD).  See
  38         @url{http://www-cs-faculty.stanford.edu/~knuth/mmix.html} for more
  39         information about MMIX.  The ELF format is used for intermediate
  40         object files in the BFD implementation.
  41
  42 @c We want to xref the symbol table node.  A feature in "chew"
  43 @c requires that "commands" do not contain spaces in the
  44 @c arguments.  Hence the hyphen in "Symbol-table".
  45 @menu
  46 @* File layout::
  47 @* Symbol-table::
  48 @* mmo section mapping::
  49 @end menu
  50
  51 INODE
  52 File layout, Symbol-table, mmo, mmo
  53 SUBSECTION
  54         File layout
  55
  56         The mmo file contents is not partitioned into named sections as
  57         with e.g.@: ELF.  Memory areas is formed by specifying the
  58         location of the data that follows.  Only the memory area
  59         @samp{0x0000@dots{}00} to @samp{0x01ff@dots{}ff} is executable, so
  60         it is used for code (and constants) and the area
  61         @samp{0x2000@dots{}00} to @samp{0x20ff@dots{}ff} is used for
  62         writable data.  @xref{mmo section mapping}.
  63
  64         There is provision for specifying ``special data'' of 65536
  65         different types.  We use type 80 (decimal), arbitrarily chosen the
  66         same as the ELF <<e_machine>> number for MMIX, filling it with
  67         section information normally found in ELF objects. @xref{mmo
  68         section mapping}.
  69
  70         Contents is entered as 32-bit words, xor:ed over previous
  71         contents, always zero-initialized.  A word that starts with the
  72         byte @samp{0x98} forms a command called a @samp{lopcode}, where
  73         the next byte distinguished between the thirteen lopcodes.  The
  74         two remaining bytes, called the @samp{Y} and @samp{Z} fields, or
  75         the @samp{YZ} field (a 16-bit big-endian number), are used for
  76         various purposes different for each lopcode.  As documented in
  77         @url{http://www-cs-faculty.stanford.edu/~knuth/mmixal-intro.ps.gz},
  78         the lopcodes are:
  79
  80         @table @code
  81         @item lop_quote
  82         0x98000001.  The next word is contents, regardless of whether it
  83         starts with 0x98 or not.
  84
  85         @item lop_loc
  86         0x9801YYZZ, where @samp{Z} is 1 or 2.  This is a location
  87         directive, setting the location for the next data to the next
  88         32-bit word (for @math{Z = 1}) or 64-bit word (for @math{Z = 2}),
  89         plus @math{Y * 2^56}.  Normally @samp{Y} is 0 for the text segment
  90         and 2 for the data segment.
  91
  92         @item lop_skip
  93         0x9802YYZZ.  Increase the current location by @samp{YZ} bytes.
  94
  95         @item lop_fixo
  96         0x9803YYZZ, where @samp{Z} is 1 or 2.  Store the current location
  97         as 64 bits into the location pointed to by the next 32-bit
  98         (@math{Z = 1}) or 64-bit (@math{Z = 2}) word, plus @math{Y *
  99         2^56}.
 100
 101         @item lop_fixr
 102         0x9804YYZZ.  @samp{YZ} is stored into the current location plus
 103         @math{2 - 4 * YZ}.
 104
 105         @item lop_fixrx
 106         0x980500ZZ.  @samp{Z} is 16 or 24.  A value @samp{L} derived from
 107         the following 32-bit word are used in a manner similar to
 108         @samp{YZ} in lop_fixr: it is xor:ed into the current location
 109         minus @math{4 * L}.  The first byte of the word is 0 or 1.  If it
 110         is 1, then @math{L = (@var{lowest 24 bits of word}) - 2^Z}, if 0,
 111         then @math{L = (@var{lowest 24 bits of word})}.
 112
 113         @item lop_file
 114         0x9806YYZZ.  @samp{Y} is the file number, @samp{Z} is count of
 115         32-bit words.  Set the file number to @samp{Y} and the line
 116         counter to 0.  The next @math{Z * 4} bytes contain the file name,
 117         padded with zeros if the count is not a multiple of four.  The
 118         same @samp{Y} may occur multiple times, but @samp{Z} must be 0 for
 119         all but the first occurrence.
 120
 121         @item lop_line
 122         0x9807YYZZ.  @samp{YZ} is the line number.  Together with
 123         lop_file, it forms the source location for the next 32-bit word.
 124         Note that for each non-lopcode 32-bit word, line numbers are
 125         assumed incremented by one.
 126
 127         @item lop_spec
 128         0x9808YYZZ.  @samp{YZ} is the type number.  Data until the next
 129         lopcode other than lop_quote forms special data of type @samp{YZ}.
 130         @xref{mmo section mapping}.
 131
 132         Other types than 80, (or type 80 with a content that does not
 133         parse) is stored in sections named <<.MMIX.spec_data.@var{n}>>
 134         where @var{n} is the @samp{YZ}-type.  The flags for such a
 135         sections say not to allocate or load the data.  The vma is 0.
 136         Contents of multiple occurrences of special data @var{n} is
 137         concatenated to the data of the previous lop_spec @var{n}s.  The
 138         location in data or code at which the lop_spec occurred is lost.
 139
 140         @item lop_pre
 141         0x980901ZZ.  The first lopcode in a file.  The @samp{Z} field forms the
 142         length of header information in 32-bit words, where the first word
 143         tells the time in seconds since @samp{00:00:00 GMT Jan 1 1970}.
 144
 145         @item lop_post
 146         0x980a00ZZ.  @math{Z > 32}.  This lopcode follows after all
 147         content-generating lopcodes in a program.  The @samp{Z} field
 148         denotes the value of @samp{rG} at the beginning of the program.
 149         The following @math{256 - Z} big-endian 64-bit words are loaded
 150         into global registers @samp{$G} @dots{} @samp{$255}.
 151
 152         @item lop_stab
 153         0x980b0000.  The next-to-last lopcode in a program.  Must follow
 154         immediately after the lop_post lopcode and its data.  After this
 155         lopcode follows all symbols in a compressed format
 156         (@pxref{Symbol-table}).
 157
 158         @item lop_end
 159         0x980cYYZZ.  The last lopcode in a program.  It must follow the
 160         lop_stab lopcode and its data.  The @samp{YZ} field contains the
 161         number of 32-bit words of symbol table information after the
 162         preceding lop_stab lopcode.
 163         @end table
 164
 165         Note that the lopcode "fixups"; <<lop_fixr>>, <<lop_fixrx>> and
 166         <<lop_fixo>> are not generated by BFD, but are handled.  They are
 167         generated by <<mmixal>>.
 168
 169 EXAMPLE
 170         This trivial one-label, one-instruction file:
 171
 172 | :Main TRAP 1,2,3
 173
 174         can be represented this way in mmo:
 175
 176 | 0x98090101 - lop_pre, one 32-bit word with timestamp.
 177 | <timestamp>
 178 | 0x98010002 - lop_loc, text segment, using a 64-bit address.
 179 |              Note that mmixal does not emit this for the file above.
 180 | 0x00000000 - Address, high 32 bits.
 181 | 0x00000000 - Address, low 32 bits.
 182 | 0x98060002 - lop_file, 2 32-bit words for file-name.
 183 | 0x74657374 - "test"
 184 | 0x2e730000 - ".s\0\0"
 185 | 0x98070001 - lop_line, line 1.
 186 | 0x00010203 - TRAP 1,2,3
 187 | 0x980a00ff - lop_post, setting $255 to 0.
 188 | 0x00000000
 189 | 0x00000000
 190 | 0x980b0000 - lop_stab for ":Main" = 0, serial 1.
 191 | 0x203a4040   @xref{Symbol-table}.
 192 | 0x10404020
 193 | 0x4d206120
 194 | 0x69016e00
 195 | 0x81000000
 196 | 0x980c0005 - lop_end; symbol table contained five 32-bit words.  */
 197
 198 #include "bfd.h"
 199 #include "sysdep.h"
 200 #include "libbfd.h"
 201 #include "libiberty.h"
 202 #include "elf/mmix.h"
 203 #include "opcode/mmix.h"
 204
 205 #define LOP 0x98
 206 #define LOP_QUOTE 0
 207 #define LOP_LOC 1
 208 #define LOP_SKIP 2
 209 #define LOP_FIXO 3
 210 #define LOP_FIXR 4
 211 #define LOP_FIXRX 5
 212 #define LOP_FILE 6
 213 #define LOP_LINE 7
 214 #define LOP_SPEC 8
 215 #define LOP_PRE 9
 216 #define LOP_POST 10
 217 #define LOP_STAB 11
 218 #define LOP_END 12
 219
 220 #define LOP_QUOTE_NEXT ((LOP << 24) | (LOP_QUOTE << 16) | 1)
 221 #define SPEC_DATA_SECTION 80
 222 #define LOP_SPEC_SECTION \
 223  ((LOP << 24) | (LOP_SPEC << 16) | SPEC_DATA_SECTION)
 224
 225 /* Must be a power of two.  If you change this to be >= 64k, you need a
 226    new test-case; the ld test b-loc64k.d touches chunk-size problem areas.  */
 227 #define MMO_SEC_CONTENTS_CHUNK_SIZE (1 << 15)
 228
 229 /* An arbitrary number for the maximum length section name size.  */
 230 #define MAX_SECTION_NAME_SIZE (1024 * 1024)
 231
 232 /* A quite arbitrary number for the maximum length section size.  */
 233 #define MAX_ARTIFICIAL_SECTION_SIZE (1024 * 1024 * 1024)
 234
 235 #define MMO3_WCHAR 0x80
 236 #define MMO3_LEFT 0x40
 237 #define MMO3_MIDDLE 0x20
 238 #define MMO3_RIGHT 0x10
 239 #define MMO3_TYPEBITS 0xf
 240 #define MMO3_REGQUAL_BITS 0xf
 241 #define MMO3_UNDEF 2
 242 #define MMO3_DATA 8
 243 #define MMO3_SYMBITS 0x2f
 244
 245 /* Put these everywhere in new code.  */
 246 #define FATAL_DEBUG                                             \
 247  _bfd_abort (__FILE__, __LINE__,                                \
 248              "Internal: Non-debugged code (test-case missing)")
 249
 250 #define BAD_CASE(x)                             \
 251  _bfd_abort (__FILE__, __LINE__,                \
 252              "bad case for " #x)
 253
 254 enum mmo_sym_type { mmo_reg_sym, mmo_undef_sym, mmo_data_sym, mmo_abs_sym};
 255
 256 /* When scanning the mmo file, a linked list of mmo_symbol
 257    structures is built to represent the symbol table (if there is
 258    one).  */
 259
 260 struct mmo_symbol
 261   {
 262     struct mmo_symbol *next;
 263     char *name;
 264     bfd_vma value;
 265     enum mmo_sym_type sym_type;
 266     unsigned int serno;
 267   };
 268
 269 struct mmo_data_list_struct
 270   {
 271     struct mmo_data_list_struct *next;
 272     bfd_vma where;
 273     bfd_size_type size;
 274     bfd_size_type allocated_size;
 275     bfd_byte data[1];
 276   };
 277
 278 typedef struct mmo_data_list_struct mmo_data_list_type;
 279
 280 struct mmo_symbol_trie
 281   {
 282     struct mmo_symbol_trie *left;
 283     struct mmo_symbol_trie *right;
 284     struct mmo_symbol_trie *middle;
 285
 286     bfd_byte symchar;
 287
 288     /* A zero name means there's nothing here.  */
 289     struct mmo_symbol sym;
 290   };
 291
 292 /* The mmo tdata information.  */
 293
 294 struct mmo_data_struct
 295   {
 296     struct mmo_symbol *symbols;
 297     struct mmo_symbol *symtail;
 298     asymbol *csymbols;
 299
 300     /* File representation of time (NULL) when this file was created.  */
 301     bfd_byte created[4];
 302
 303     /* When we're reading bytes recursively, check this occasionally.
 304        Also holds write errors.  */
 305     bfd_boolean have_error;
 306
 307     /* Max symbol length that may appear in the lop_stab table.  Note that
 308        this table might just hold a subset of symbols for not-really large
 309        programs, as it can only be 65536 * 4 bytes large.  */
 310     int max_symbol_length;
 311
 312     /* Here's the symbol we build in lop_stab.  */
 313     char *lop_stab_symbol;
 314
 315     /* Index into lop_stab_symbol for the next character when parsing the
 316        symbol information.  */
 317     int symbol_position;
 318
 319     /* When creating arbitrary sections, we need to count section numbers.  */
 320     int sec_no;
 321
 322     /* When writing or reading byte-wise, we need to count the bytes
 323        within a 32-bit word.  */
 324     int byte_no;
 325
 326     /* We also need a buffer to hold the bytes we count reading or writing.  */
 327     bfd_byte buf[4];
 328   };
 329
 330 typedef struct mmo_data_struct tdata_type;
 331
 332 struct mmo_section_data_struct
 333   {
 334     mmo_data_list_type *head;
 335     mmo_data_list_type *tail;
 336   };
 337
 338 #define mmo_section_data(sec) \
 339   ((struct mmo_section_data_struct *) (sec)->used_by_bfd)
 340
 341 /* These structures are used in bfd_map_over_sections constructs.  */
 342
 343 /* Used when writing out sections; all but the register contents section
 344    which is stored in reg_section.  */
 345 struct mmo_write_sec_info
 346   {
 347     asection *reg_section;
 348     bfd_boolean retval;
 349   };
 350
 351 /* Used when trying to find a section corresponding to addr.  */
 352 struct mmo_find_sec_info
 353   {
 354     asection *sec;
 355     bfd_vma addr;
 356   };
 357
 358 static bfd_boolean mmo_bfd_copy_private_bfd_data (bfd *, bfd *);
 359 static void mmo_write_section_unless_reg_contents (bfd *, asection *, void *);
 360 static void mmo_find_sec_w_addr (bfd *, asection *, void *);
 361 static void mmo_find_sec_w_addr_grow (bfd *, asection *, void *);
 362 static asection *mmo_make_section (bfd *, const char *);
 363 static void mmo_get_symbol_info (bfd *, asymbol *, symbol_info *);
 364 static void mmo_print_symbol (bfd *, void *, asymbol *,
 365                               bfd_print_symbol_type);
 366 static void mmo_init (void);
 367 static bfd_boolean mmo_mkobject (bfd *);
 368 static bfd_boolean mmo_scan (bfd *);
 369 static asection *mmo_decide_section (bfd *, bfd_vma);
 370 static asection *mmo_get_generic_spec_data_section (bfd *, int);
 371 static asection *mmo_get_spec_section (bfd *, int);
 372 static INLINE bfd_byte *mmo_get_loc (asection *, bfd_vma, int);
 373 static void mmo_xore_64 (asection *, bfd_vma vma, bfd_vma value);
 374 static void mmo_xore_32 (asection *, bfd_vma vma, unsigned int);
 375 static void mmo_xore_16 (asection *, bfd_vma vma, unsigned int);
 376 static const bfd_target *mmo_object_p (bfd *);
 377 static void mmo_map_set_sizes (bfd *, asection *, void *);
 378 static bfd_boolean mmo_get_symbols (bfd *);
 379 static bfd_boolean mmo_create_symbol (bfd *, const char *, bfd_vma,
 380                                       enum mmo_sym_type, unsigned int);
 381 static bfd_boolean mmo_get_section_contents (bfd *, asection *, void *,
 382                                              file_ptr, bfd_size_type);
 383 static long mmo_get_symtab_upper_bound (bfd *);
 384 static long mmo_canonicalize_symtab (bfd *, asymbol **);
 385 static void mmo_get_symbol_info (bfd *, asymbol *, symbol_info *);
 386 static void mmo_print_symbol (bfd *, void *, asymbol *,
 387                               bfd_print_symbol_type);
 388 static bfd_boolean mmo_set_section_contents (bfd *, sec_ptr, const void *,
 389                                              file_ptr, bfd_size_type);
 390 static int mmo_sizeof_headers (bfd *, bfd_boolean);
 391 static long mmo_get_reloc_upper_bound (bfd *, asection *);
 392 static bfd_boolean mmo_internal_write_header (bfd *);
 393 static bfd_boolean mmo_internal_write_post (bfd *, int, asection *);
 394 static bfd_boolean mmo_internal_add_3_sym (bfd *, struct mmo_symbol_trie *,
 395                                            const struct mmo_symbol *);
 396 static unsigned int mmo_internal_3_length (bfd *, struct mmo_symbol_trie *);
 397 static void mmo_internal_3_dump (bfd *, struct mmo_symbol_trie *);
 398 static void mmo_beb128_out (bfd *, int, int);
 399 static bfd_boolean mmo_internal_write_section (bfd *, asection *);
 400 static void mmo_write_tetra (bfd *, unsigned int);
 401 static void mmo_write_tetra_raw (bfd *, unsigned int);
 402 static void mmo_write_octa (bfd *, bfd_vma);
 403 static void mmo_write_octa_raw (bfd *, bfd_vma);
 404 static bfd_boolean mmo_write_chunk (bfd *, const bfd_byte *, unsigned int);
 405 static bfd_boolean mmo_flush_chunk (bfd *);
 406 static bfd_boolean mmo_write_loc_chunk (bfd *, bfd_vma, const bfd_byte *,
 407                                         unsigned int, bfd_vma *);
 408 static bfd_boolean mmo_write_chunk_list (bfd *, mmo_data_list_type *);
 409 static bfd_boolean mmo_write_loc_chunk_list (bfd *, mmo_data_list_type *);
 410 static bfd_boolean mmo_write_symbols_and_terminator (bfd *);
 411 static flagword mmo_sec_flags_from_bfd_flags (flagword);
 412 static flagword bfd_sec_flags_from_mmo_flags (flagword);
 413 static bfd_byte mmo_get_byte (bfd *);
 414 static void mmo_write_byte (bfd *, bfd_byte);
 415 static bfd_boolean mmo_new_section_hook (bfd *, asection *);
 416 static int mmo_sort_mmo_symbols (const void *, const void *);
 417 static bfd_boolean mmo_write_object_contents (bfd *);
 418 static long mmo_canonicalize_reloc (bfd *, sec_ptr, arelent **, asymbol **);
 419 static bfd_boolean mmo_write_section_description (bfd *, asection *);
 420 static bfd_boolean mmo_has_leading_or_trailing_zero_tetra_p (bfd *,
 421                                                              asection *);
 422
 423 /* Global "const" variables initialized once.  Must not depend on
 424    particular input or caller; put such things into the bfd or elsewhere.
 425    Look ma, no static per-invocation data!  */
 426
 427 static
 428 char valid_mmo_symbol_character_set[/* A-Z a-z (we assume consecutive
 429                                        codes; sorry EBCDIC:ers!).  */
 430                                     + 'Z' - 'A' + 1 + 'z' - 'a' + 1
 431                                     /* Digits.  */
 432                                     + 10
 433                                     /* ':' and '_'.  */
 434                                     + 1 + 1
 435                                     /* Codes higher than 126.  */
 436                                     + 256 - 126
 437                                     /* Ending zero.  */
 438                                     + 1];
 439
 440
 441 /* Get section SECNAME or create one if it doesn't exist.  When creating
 442    one, new memory for the name is allocated.  */
 443
 444 static asection *
 445 mmo_make_section (bfd *abfd, const char *secname)
 446 {
 447   asection *sec = bfd_get_section_by_name (abfd, secname);
 448
 449   if (sec == NULL)
 450     {
 451       char *newsecname = strdup (secname);
 452
 453       if (newsecname == NULL)
 454         {
 455           (*_bfd_error_handler)
 456             (_("%s: No core to allocate section name %s\n"),
 457              bfd_get_filename (abfd), secname);
 458           bfd_set_error (bfd_error_system_call);
 459           return NULL;
 460         }
 461       sec = bfd_make_section (abfd, newsecname);
 462     }
 463
 464   return sec;
 465 }
 466
 467 /* Nothing to do, but keep as a placeholder if we need it.
 468    Note that state that might differ between bfd:s must not be initialized
 469    here, nor must it be static.  Add it to tdata information instead.  */
 470
 471 static void
 472 mmo_init (void)
 473 {
 474   static bfd_boolean inited = FALSE;
 475   int i = 0;
 476   int j = 0;
 477   static const char letters[]
 478     = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789:_";
 479
 480   if (inited)
 481     return;
 482   inited = TRUE;
 483
 484   /* Fill in the set of valid symbol characters.  */
 485   strcpy (valid_mmo_symbol_character_set, letters);
 486   i = strlen (letters);
 487
 488   for (j = 126; j < 256; j++)
 489     valid_mmo_symbol_character_set[i++] = j;
 490 }
 491
 492 /* Check whether an existing file is an mmo file.  */
 493
 494 static const bfd_target *
 495 mmo_object_p (bfd *abfd)
 496 {
 497   struct stat statbuf;
 498   bfd_byte b[4];
 499
 500   mmo_init ();
 501
 502   if (bfd_stat (abfd, &statbuf) < 0
 503       || bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0
 504       || bfd_bread (b, 4, abfd) != 4)
 505     goto bad_final;
 506
 507   /* All mmo files are a multiple of four bytes long.
 508      Only recognize version one.  */
 509   if ((statbuf.st_size % 4) != 0
 510       || b[0] != LOP || b[1] != LOP_PRE || b[2] != 1)
 511     goto bad_format;
 512
 513   /* Get the last 32-bit word.  */
 514   if (bfd_seek (abfd, (file_ptr) statbuf.st_size - 4, SEEK_SET) != 0
 515       || bfd_bread (b, 4, abfd) != 4)
 516     goto bad_final;
 517
 518   /* Check if the file ends in a lop_end lopcode. */
 519   if (b[0] != LOP || b[1] != LOP_END || ! mmo_mkobject (abfd))
 520     goto bad_format;
 521
 522   /* Compute an upper bound on the max symbol length.  Not really
 523      important as all of the symbol information can only be 256k.  */
 524   abfd->tdata.mmo_data->max_symbol_length = (b[2] * 256 + b[3]) * 4;
 525   abfd->tdata.mmo_data->lop_stab_symbol
 526     = bfd_malloc (abfd->tdata.mmo_data->max_symbol_length + 1);
 527
 528   if (abfd->tdata.mmo_data->lop_stab_symbol == NULL)
 529     {
 530       (*_bfd_error_handler)
 531         (_("%s: No core to allocate a symbol %d bytes long\n"),
 532          bfd_get_filename (abfd), abfd->tdata.mmo_data->max_symbol_length);
 533       goto bad_final;
 534     }
 535
 536   /* Read in everything.  */
 537   if (! mmo_scan (abfd))
 538     goto bad_format_free;
 539
 540   if (abfd->symcount > 0)
 541     abfd->flags |= HAS_SYMS;
 542
 543   /* You'll have to tweak this if you want to use this format for other
 544      arches (not recommended due to its small-size limitations).  Look at
 545      the ELF format for how to make it target-generic.  */
 546   if (! bfd_default_set_arch_mach (abfd, bfd_arch_mmix, 0))
 547     goto bad_format_free;
 548
 549   return abfd->xvec;
 550
 551  bad_format_free:
 552   free (abfd->tdata.mmo_data->lop_stab_symbol);
 553  bad_format:
 554   bfd_set_error (bfd_error_wrong_format);
 555  bad_final:
 556   return NULL;
 557 }
 558
 559 /* Set up the mmo tdata information.  */
 560
 561 static bfd_boolean
 562 mmo_mkobject (bfd *abfd)
 563 {
 564   mmo_init ();
 565
 566   if (abfd->tdata.mmo_data == NULL)
 567     {
 568       time_t created;
 569
 570       /* All fields are zero-initialized, so we don't have to explicitly
 571          initialize most.  */
 572       tdata_type *tdata = (tdata_type *) bfd_zmalloc (sizeof (tdata_type));
 573       if (tdata == NULL)
 574         return FALSE;
 575
 576       created = time (NULL);
 577       bfd_put_32 (abfd, created, tdata->created);
 578
 579       abfd->tdata.mmo_data = tdata;
 580     }
 581
 582   return TRUE;
 583 }
 584
 585 static bfd_boolean
 586 mmo_bfd_copy_private_bfd_data (bfd *ibfd, bfd *obfd)
 587 {
 588   if (bfd_get_flavour (ibfd) != bfd_target_mmo_flavour
 589       || bfd_get_flavour (obfd) != bfd_target_mmo_flavour)
 590     return TRUE;
 591
 592   /* Copy the time the copied-from file was created.  If people want the
 593      time the file was last *modified*, they have that in the normal file
 594      information.  */
 595   memcpy (obfd->tdata.mmo_data->created, ibfd->tdata.mmo_data->created,
 596           sizeof (obfd->tdata.mmo_data->created));
 597   return TRUE;
 598 }
 599
 600 /* Helper functions for mmo_decide_section, used through
 601    bfd_map_over_sections.  */
 602
 603 static void
 604 mmo_find_sec_w_addr (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *p)
 605 {
 606   struct mmo_find_sec_info *infop = (struct mmo_find_sec_info *) p;
 607   bfd_vma vma = bfd_get_section_vma (abfd, sec);
 608
 609   /* Ignore sections that aren't loaded.  */
 610   if ((bfd_get_section_flags (abfd, sec) & (SEC_LOAD | SEC_ALLOC))
 611       !=  (SEC_LOAD | SEC_ALLOC))
 612     return;
 613
 614   if (infop->addr >= vma && infop->addr < vma + sec->size)
 615     infop->sec = sec;
 616 }
 617
 618 static void
 619 mmo_find_sec_w_addr_grow (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *p)
 620 {
 621   struct mmo_find_sec_info *infop = (struct mmo_find_sec_info *) p;
 622   bfd_vma vma = bfd_get_section_vma (abfd, sec);
 623
 624   /* Ignore sections that aren't loaded.  */
 625   if ((bfd_get_section_flags (abfd, sec) & (SEC_LOAD | SEC_ALLOC))
 626       !=  (SEC_LOAD | SEC_ALLOC))
 627     return;
 628
 629   if (infop->addr >= vma && infop->addr < vma + MAX_ARTIFICIAL_SECTION_SIZE)
 630     infop->sec = sec;
 631 }
 632
 633 /* Find a section that corresponds to a VMA.  Automatically create .text
 634    or .data and set current section to it, depending on what vma.  If we
 635    can't deduce a section, make one up as ".MMIX.sec.N", where N is an
 636    increasing number.  */
 637
 638 static asection *
 639 mmo_decide_section (bfd *abfd, bfd_vma vma)
 640 {
 641   asection *sec = NULL;
 642   char sec_name[sizeof (".MMIX.sec.") + 20];
 643   struct mmo_find_sec_info info;
 644
 645   info.addr = vma;
 646   info.sec = NULL;
 647
 648   /* First see if there's a section that would match exactly.  */
 649   bfd_map_over_sections (abfd, mmo_find_sec_w_addr, &info);
 650
 651   if (info.sec != NULL)
 652     return info.sec;
 653
 654   /* If there's no such section, try and expand one of the existing ones,
 655      up to a limit.  Make sure we have .text and .data before we try that;
 656      create them corresponding to expected addresses and set flags to make
 657      them match the "loaded and with contents" expectation.  */
 658   if ((vma >> 56) == 0)
 659     {
 660       sec = bfd_make_section_old_way (abfd, MMO_TEXT_SECTION_NAME);
 661
 662       if (sec == NULL)
 663         return NULL;
 664
 665       if (! sec->user_set_vma)
 666         bfd_set_section_vma (abfd, sec, vma);
 667       if (! bfd_set_section_flags (abfd, sec,
 668                                    bfd_get_section_flags (abfd, sec)
 669                                    | SEC_CODE | SEC_LOAD | SEC_ALLOC))
 670         return NULL;
 671     }
 672   else if ((vma >> 56) == 0x20)
 673     {
 674       sec = bfd_make_section_old_way (abfd, MMO_DATA_SECTION_NAME);
 675
 676       if (sec == NULL)
 677         return NULL;
 678
 679       if (! sec->user_set_vma)
 680         bfd_set_section_vma (abfd, sec, vma);
 681       if (! bfd_set_section_flags (abfd, sec,
 682                                    bfd_get_section_flags (abfd, sec)
 683                                    | SEC_LOAD | SEC_ALLOC))
 684         return NULL;
 685     }
 686
 687   bfd_map_over_sections (abfd, mmo_find_sec_w_addr_grow, &info);
 688
 689   if (info.sec != NULL)
 690     return info.sec;
 691
 692   /* If there's still no suitable section, make a new one.  */
 693   sprintf (sec_name, ".MMIX.sec.%d", abfd->tdata.mmo_data->sec_no++);
 694   sec = mmo_make_section (abfd, sec_name);
 695   if (! sec->user_set_vma)
 696     bfd_set_section_vma (abfd, sec, vma);
 697
 698   if (! bfd_set_section_flags (abfd, sec,
 699                                bfd_get_section_flags (abfd, sec)
 700                                | SEC_LOAD | SEC_ALLOC))
 701     return NULL;
 702   return sec;
 703 }
 704
 705 /* Xor in a 64-bit value VALUE at VMA.  */
 706
 707 static INLINE void
 708 mmo_xore_64 (asection *sec, bfd_vma vma, bfd_vma value)
 709 {
 710   bfd_byte *loc = mmo_get_loc (sec, vma, 8);
 711   bfd_vma prev = bfd_get_64 (sec->owner, loc);
 712
 713   value ^= prev;
 714   bfd_put_64 (sec->owner, value, loc);
 715 }
 716
 717 /* Xor in a 32-bit value VALUE at VMA.  */
 718
 719 static INLINE void
 720 mmo_xore_32 (asection *sec, bfd_vma vma, unsigned int value)
 721 {
 722   bfd_byte *loc = mmo_get_loc (sec, vma, 4);
 723   unsigned int prev = bfd_get_32 (sec->owner, loc);
 724
 725   value ^= prev;
 726   bfd_put_32 (sec->owner, value, loc);
 727 }
 728
 729 /* Xor in a 16-bit value VALUE at VMA.  */
 730
 731 static INLINE void
 732 mmo_xore_16 (asection *sec, bfd_vma vma, unsigned int value)
 733 {
 734   bfd_byte *loc = mmo_get_loc (sec, vma, 2);
 735   unsigned int prev = bfd_get_16 (sec->owner, loc);
 736
 737   value ^= prev;
 738   bfd_put_16 (sec->owner, value, loc);
 739 }
 740
 741 /* Write a 32-bit word to output file, no lop_quote generated.  */
 742
 743 static INLINE void
 744 mmo_write_tetra_raw (bfd *abfd, unsigned int value)
 745 {
 746   bfd_byte buf[4];
 747
 748   bfd_put_32 (abfd, value, buf);
 749
 750   if (bfd_bwrite (buf, 4, abfd) != 4)
 751     abfd->tdata.mmo_data->have_error = TRUE;
 752 }
 753
 754 /* Write a 32-bit word to output file; lop_quote if necessary.  */
 755
 756 static INLINE void
 757 mmo_write_tetra (bfd *abfd, unsigned int value)
 758 {
 759   if (((value >> 24) & 0xff) == LOP)
 760     mmo_write_tetra_raw (abfd, LOP_QUOTE_NEXT);
 761
 762   mmo_write_tetra_raw (abfd, value);
 763 }
 764
 765 /* Write a 64-bit word to output file, perhaps with lop_quoting.  */
 766
 767 static INLINE void
 768 mmo_write_octa (bfd *abfd, bfd_vma value)
 769 {
 770   mmo_write_tetra (abfd, (unsigned int) (value >> 32));
 771   mmo_write_tetra (abfd, (unsigned int) value);
 772 }
 773
 774 /* Write a 64-bit word to output file, without lop_quoting.  */
 775
 776 static INLINE void
 777 mmo_write_octa_raw (bfd *abfd, bfd_vma value)
 778 {
 779   mmo_write_tetra_raw (abfd, (unsigned int) (value >> 32));
 780   mmo_write_tetra_raw (abfd, (unsigned int) value);
 781 }
 782
 783 /* Write quoted contents.  Intended to be called multiple times in
 784    sequence, followed by a call to mmo_flush_chunk.  */
 785
 786 static INLINE bfd_boolean
 787 mmo_write_chunk (bfd *abfd, const bfd_byte *loc, unsigned int len)
 788 {
 789   bfd_boolean retval = TRUE;
 790
 791   /* Fill up a tetra from bytes remaining from a previous chunk.  */
 792   if (abfd->tdata.mmo_data->byte_no != 0)
 793     {
 794       while (abfd->tdata.mmo_data->byte_no < 4 && len != 0)
 795         {
 796           abfd->tdata.mmo_data->buf[abfd->tdata.mmo_data->byte_no++] = *loc++;
 797           len--;
 798         }
 799
 800       if (abfd->tdata.mmo_data->byte_no == 4)
 801         {
 802           mmo_write_tetra (abfd,
 803                            bfd_get_32 (abfd, abfd->tdata.mmo_data->buf));
 804           abfd->tdata.mmo_data->byte_no = 0;
 805         }
 806     }
 807
 808   while (len >= 4)
 809     {
 810       if (loc[0] == LOP)
 811         mmo_write_tetra_raw (abfd, LOP_QUOTE_NEXT);
 812
 813       retval = (retval
 814                 && ! abfd->tdata.mmo_data->have_error
 815                 && 4 == bfd_bwrite (loc, 4, abfd));
 816
 817       loc += 4;
 818       len -= 4;
 819     }
 820
 821   if (len)
 822     {
 823       memcpy (abfd->tdata.mmo_data->buf, loc, len);
 824       abfd->tdata.mmo_data->byte_no = len;
 825     }
 826
 827   if (! retval)
 828     abfd->tdata.mmo_data->have_error = TRUE;
 829   return retval;
 830 }
 831
 832 /* Flush remaining bytes, from a previous mmo_write_chunk, zero-padded to
 833    4 bytes.  */
 834
 835 static INLINE bfd_boolean
 836 mmo_flush_chunk (bfd *abfd)
 837 {
 838   if (abfd->tdata.mmo_data->byte_no != 0)
 839     {
 840       memset (abfd->tdata.mmo_data->buf + abfd->tdata.mmo_data->byte_no,
 841               0, 4 - abfd->tdata.mmo_data->byte_no);
 842       mmo_write_tetra (abfd,
 843                        bfd_get_32 (abfd, abfd->tdata.mmo_data->buf));
 844       abfd->tdata.mmo_data->byte_no = 0;
 845     }
 846
 847   return ! abfd->tdata.mmo_data->have_error;
 848 }
 849
 850 /* Same, but from a list.  */
 851
 852 static INLINE bfd_boolean
 853 mmo_write_chunk_list (bfd *abfd, mmo_data_list_type *datap)
 854 {
 855   for (; datap != NULL; datap = datap->next)
 856     if (! mmo_write_chunk (abfd, datap->data, datap->size))
 857       return FALSE;
 858
 859   return mmo_flush_chunk (abfd);
 860 }
 861
 862 /* Write a lop_loc and some contents.  A caller needs to call
 863    mmo_flush_chunk after calling this function.  The location is only
 864    output if different than *LAST_VMAP, which is updated after this call.  */
 865
 866 static bfd_boolean
 867 mmo_write_loc_chunk (bfd *abfd, bfd_vma vma, const bfd_byte *loc,
 868                      unsigned int len, bfd_vma *last_vmap)
 869 {
 870   /* Find an initial and trailing section of zero tetras; we don't need to
 871      write out zeros.  FIXME: When we do this, we should emit section size
 872      and address specifiers, else objcopy can't always perform an identity
 873      translation.  Only do this if we *don't* have left-over data from a
 874      previous write or the vma of this chunk is *not* the next address,
 875      because then data isn't tetrabyte-aligned and we're concatenating to
 876      that left-over data.  */
 877
 878   if (abfd->tdata.mmo_data->byte_no == 0 || vma != *last_vmap)
 879     {
 880       while (len >= 4 && bfd_get_32 (abfd, loc) == 0)
 881         {
 882           vma += 4;
 883           len -= 4;
 884           loc += 4;
 885         }
 886
 887       while (len >= 4 && bfd_get_32 (abfd, loc + len - 4) == 0)
 888         len -= 4;
 889     }
 890
 891   /* Only write out the location if it's different than the one the caller
 892      (supposedly) previously handled, accounting for omitted leading zeros.  */
 893   if (vma != *last_vmap)
 894     {
 895       /* We might be in the middle of a sequence.  */
 896       mmo_flush_chunk (abfd);
 897
 898       /* We always write the location as 64 bits; no use saving bytes
 899          here.  */
 900       mmo_write_tetra_raw (abfd, (LOP << 24) | (LOP_LOC << 16) | 2);
 901       mmo_write_octa_raw (abfd, vma);
 902     }
 903
 904   /* Update to reflect end of this chunk, with trailing zeros omitted.  */
 905   *last_vmap = vma + len;
 906
 907   return (! abfd->tdata.mmo_data->have_error
 908           && mmo_write_chunk (abfd, loc, len));
 909 }
 910
 911 /* Same, but from a list.  */
 912
 913 static INLINE bfd_boolean
 914 mmo_write_loc_chunk_list (bfd *abfd, mmo_data_list_type *datap)
 915 {
 916   /* Get an address different than the address of the first chunk.  */
 917   bfd_vma last_vma = datap ? datap->where - 1 : 0;
 918
 919   for (; datap != NULL; datap = datap->next)
 920     if (! mmo_write_loc_chunk (abfd, datap->where, datap->data, datap->size,
 921                                &last_vma))
 922       return FALSE;
 923
 924   return mmo_flush_chunk (abfd);
 925 }
 926
 927 /* Make a .MMIX.spec_data.N section.  */
 928
 929 static asection *
 930 mmo_get_generic_spec_data_section (bfd *abfd, int spec_data_number)
 931 {
 932   asection *sec;
 933   char secname[sizeof (MMIX_OTHER_SPEC_SECTION_PREFIX) + 20]
 934     = MMIX_OTHER_SPEC_SECTION_PREFIX;
 935
 936   sprintf (secname + strlen (MMIX_OTHER_SPEC_SECTION_PREFIX),
 937            "%d", spec_data_number);
 938
 939   sec = mmo_make_section (abfd, secname);
 940
 941   return sec;
 942 }
 943
 944 /* Make a special section for SPEC_DATA_NUMBER.  If it is the one we use
 945    ourselves, parse some of its data to get at the section name.  */
 946
 947 static asection *
 948 mmo_get_spec_section (bfd *abfd, int spec_data_number)
 949 {
 950   char *secname;
 951   asection *sec;
 952   bfd_byte buf[4];
 953   unsigned int secname_length;
 954   unsigned int i;
 955   bfd_vma section_length;
 956   bfd_vma section_vma;
 957   mmo_data_list_type *loc;
 958   flagword flags;
 959   long orig_pos;
 960
 961   /* If this isn't the "special" special data, then make a placeholder
 962      section.  */
 963   if (spec_data_number != SPEC_DATA_SECTION)
 964     return mmo_get_generic_spec_data_section (abfd, spec_data_number);
 965
 966   /* Seek back to this position if there was a format error.  */
 967   orig_pos = bfd_tell (abfd);
 968
 969   /* Read the length (in 32-bit words).  */
 970   if (bfd_bread (buf, 4, abfd) != 4)
 971     goto format_error;
 972
 973   if (buf[0] == LOP)
 974     {
 975       if (buf[1] != LOP_QUOTE)
 976         goto format_error;
 977
 978       if (bfd_bread (buf, 4, abfd) != 4)
 979         goto format_error;
 980     }
 981
 982   /* We don't care to keep the name length accurate.  It's
 983      zero-terminated.  */
 984   secname_length = bfd_get_32 (abfd, buf) * 4;
 985
 986   /* Check section name length for sanity.  */
 987   if (secname_length > MAX_SECTION_NAME_SIZE)
 988     goto format_error;
 989
 990   /* This should be free'd regardless if a section is created.  */
 991   secname = bfd_malloc (secname_length + 1);
 992   secname[secname_length] = 0;
 993
 994   for (i = 0; i < secname_length / 4; i++)
 995     {
 996       if (bfd_bread (secname + i * 4, 4, abfd) != 4)
 997         goto format_error_free;
 998
 999       if (secname[i * 4] == (char) LOP)
1000         {
1001           /* A bit of overkill, but we handle char 0x98 in a section name,
1002              and recognize misparsing.  */
1003           if (secname[i * 4 + 1] != LOP_QUOTE
1004               || bfd_bread (secname + i * 4, 4, abfd) != 4)
1005             /* Whoops.  We thought this was a name, and now we found a
1006                non-lop_quote lopcode before we parsed the whole length of
1007                the name.  Signal end-of-file in the same manner.  */
1008               goto format_error_free;
1009         }
1010     }
1011
1012   /* Get the section flags.  */
1013   if (bfd_bread (buf, 4, abfd) != 4
1014       || (buf[0] == LOP
1015           && (buf[1] != LOP_QUOTE || bfd_bread (buf, 4, abfd) != 4)))
1016     goto format_error_free;
1017
1018   flags = bfd_get_32 (abfd, buf);
1019
1020   /* Get the section length.  */
1021   if (bfd_bread (buf, 4, abfd) != 4
1022       || (buf[0] == LOP
1023           && (buf[1] != LOP_QUOTE || bfd_bread (buf, 4, abfd) != 4)))
1024     goto format_error_free;
1025
1026   section_length = (bfd_vma) bfd_get_32 (abfd, buf) << 32;
1027
1028   /* That's the first, high-part.  Now get the low part.  */
1029
1030   if (bfd_bread (buf, 4, abfd) != 4
1031       || (buf[0] == LOP
1032           && (buf[1] != LOP_QUOTE || bfd_bread (buf, 4, abfd) != 4)))
1033     goto format_error_free;
1034
1035   section_length |= (bfd_vma) bfd_get_32 (abfd, buf);
1036
1037   /* Check the section length for sanity.  */
1038   if (section_length > MAX_ARTIFICIAL_SECTION_SIZE)
1039     goto format_error_free;
1040
1041   /* Get the section VMA.  */
1042   if (bfd_bread (buf, 4, abfd) != 4
1043       || (buf[0] == LOP
1044           && (buf[1] != LOP_QUOTE || bfd_bread (buf, 4, abfd) != 4)))
1045     goto format_error_free;
1046
1047   section_vma = (bfd_vma) bfd_get_32 (abfd, buf) << 32;
1048
1049   /* That's the first, high-part.  Now get the low part.  */
1050   if (bfd_bread (buf, 4, abfd) != 4
1051       || (buf[0] == LOP
1052           && (buf[1] != LOP_QUOTE || bfd_bread (buf, 4, abfd) != 4)))
1053     goto format_error_free;
1054
1055   section_vma |= (bfd_vma) bfd_get_32 (abfd, buf);
1056
1057   sec = mmo_make_section (abfd, secname);
1058   free (secname);
1059   if (sec == NULL)
1060     goto format_error;
1061
1062   /* We allocate a buffer here for the advertised size, with head room for
1063      tetrabyte alignment.  */
1064   loc = bfd_zmalloc (section_length + 3
1065                      + sizeof (struct mmo_data_list_struct));
1066   if (loc == NULL)
1067     goto format_error;
1068
1069   /* Use a TETRA-rounded size for the allocated buffer; we set the
1070      "visible" section size below.  */
1071   loc->size = (section_length + 3) & ~3;
1072
1073   /* Add in the section flags we found to those bfd entered during this
1074      process and set the contents.  */
1075   if (! bfd_set_section_flags (abfd, sec,
1076                                bfd_sec_flags_from_mmo_flags (flags)
1077                                | bfd_get_section_flags (abfd, sec)
1078                                | (section_length != 0 ? SEC_HAS_CONTENTS : 0))
1079       || ! bfd_set_section_size (abfd, sec, sec->size + section_length)
1080       /* Set VMA only for the first occurrence.  */
1081       || (! sec->user_set_vma
1082           && ! bfd_set_section_vma  (abfd, sec, section_vma)))
1083     {
1084       /* If we get an error for any of the calls above, signal more than
1085          just a format error for the spec section.  */
1086       return NULL;
1087     }
1088
1089   loc->next = NULL;
1090   if (mmo_section_data (sec)->tail != NULL)
1091     mmo_section_data (sec)->tail->next = loc;
1092   else
1093     mmo_section_data (sec)->head = loc;
1094   mmo_section_data (sec)->tail = loc;
1095   loc->where = section_vma;
1096
1097   return sec;
1098
1099  format_error_free:
1100   free (secname);
1101  format_error:
1102   if (bfd_seek (abfd, orig_pos, SEEK_SET) != 0)
1103     return NULL;
1104
1105   return mmo_get_generic_spec_data_section (abfd, spec_data_number);
1106 }
1107
1108 /* Read a byte, but read from file in multiples of 32-bit words.  */
1109
1110 static bfd_byte
1111 mmo_get_byte (bfd *abfd)
1112 {
1113   bfd_byte retval;
1114
1115   if (abfd->tdata.mmo_data->byte_no == 0)
1116     {
1117       if (! abfd->tdata.mmo_data->have_error
1118           && bfd_bread (abfd->tdata.mmo_data->buf, 4, abfd) != 4)
1119         {
1120           abfd->tdata.mmo_data->have_error = TRUE;
1121
1122           /* A value somewhat safe against tripping on some inconsistency
1123              when mopping up after this error.  */
1124           return 128;
1125         }
1126     }
1127
1128   retval = abfd->tdata.mmo_data->buf[abfd->tdata.mmo_data->byte_no];
1129   abfd->tdata.mmo_data->byte_no = (abfd->tdata.mmo_data->byte_no + 1) % 4;
1130
1131   return retval;
1132 }
1133
1134 /* Write a byte, in multiples of 32-bit words.  */
1135
1136 static void
1137 mmo_write_byte (bfd *abfd, bfd_byte value)
1138 {
1139   abfd->tdata.mmo_data->buf[(abfd->tdata.mmo_data->byte_no++ % 4)] = value;
1140   if ((abfd->tdata.mmo_data->byte_no % 4) == 0)
1141     {
1142       if (! abfd->tdata.mmo_data->have_error
1143           && bfd_bwrite (abfd->tdata.mmo_data->buf, 4, abfd) != 4)
1144         abfd->tdata.mmo_data->have_error = TRUE;
1145     }
1146 }
1147
1148 /* Create a symbol.  */
1149
1150 static bfd_boolean
1151 mmo_create_symbol (bfd *abfd, const char *symname, bfd_vma addr, enum
1152                    mmo_sym_type sym_type, unsigned int serno)
1153 {
1154   struct mmo_symbol *n;
1155
1156   n = (struct mmo_symbol *) bfd_alloc (abfd, sizeof (struct mmo_symbol));
1157   if (n == NULL)
1158     return FALSE;
1159
1160   n->name = bfd_alloc (abfd, strlen (symname) + 1);
1161   if (n->name == NULL)
1162     return FALSE;
1163
1164   strcpy (n->name, symname);
1165
1166   n->value = addr;
1167   n->sym_type = sym_type;
1168   n->serno = serno;
1169
1170   if (abfd->tdata.mmo_data->symbols == NULL)
1171     abfd->tdata.mmo_data->symbols = n;
1172   else
1173     abfd->tdata.mmo_data->symtail->next = n;
1174   abfd->tdata.mmo_data->symtail = n;
1175   n->next = NULL;
1176
1177   ++abfd->symcount;
1178
1179   /* Check that :Main equals the last octa of the .MMIX.reg_contents
1180      section, as it's the one place we're sure to pass when reading a mmo
1181      object.  For written objects, we do it while setting the symbol
1182      table.  */
1183   if (strcmp (symname, MMIX_START_SYMBOL_NAME) == 0
1184       && bfd_get_start_address (abfd) != addr)
1185     {
1186       (*_bfd_error_handler)
1187         (_("%s: invalid mmo file: initialization value for $255 is not `Main'\n"),
1188          bfd_get_filename (abfd));
1189       bfd_set_error (bfd_error_bad_value);
1190       return FALSE;
1191     }
1192
1193   return TRUE;
1194 }
1195
1196 /* Read in symbols.  */
1197
1198 static bfd_boolean
1199 mmo_get_symbols (bfd *abfd)
1200 {
1201 /*
1202 INODE
1203 Symbol-table, mmo section mapping, File layout, mmo
1204 SUBSECTION
1205         Symbol table format
1206
1207         From mmixal.w (or really, the generated mmixal.tex) in
1208         @url{http://www-cs-faculty.stanford.edu/~knuth/programs/mmix.tar.gz}):
1209         ``Symbols are stored and retrieved by means of a @samp{ternary
1210         search trie}, following ideas of Bentley and Sedgewick. (See
1211         ACM--SIAM Symp.@: on Discrete Algorithms @samp{8} (1997), 360--369;
1212         R.@:Sedgewick, @samp{Algorithms in C} (Reading, Mass.@:
1213         Addison--Wesley, 1998), @samp{15.4}.)  Each trie node stores a
1214         character, and there are branches to subtries for the cases where
1215         a given character is less than, equal to, or greater than the
1216         character in the trie.  There also is a pointer to a symbol table
1217         entry if a symbol ends at the current node.''
1218
1219         So it's a tree encoded as a stream of bytes.  The stream of bytes
1220         acts on a single virtual global symbol, adding and removing
1221         characters and signalling complete symbol points.  Here, we read
1222         the stream and create symbols at the completion points.
1223
1224         First, there's a control byte <<m>>.  If any of the listed bits
1225         in <<m>> is nonzero, we execute what stands at the right, in
1226         the listed order:
1227
1228 | (MMO3_LEFT)
1229 | 0x40 - Traverse left trie.
1230 |        (Read a new command byte and recurse.)
1231 |
1232 | (MMO3_SYMBITS)
1233 | 0x2f - Read the next byte as a character and store it in the
1234 |        current character position; increment character position.
1235 |        Test the bits of <<m>>:
1236 |
1237 |        (MMO3_WCHAR)
1238 |        0x80 - The character is 16-bit (so read another byte,
1239 |               merge into current character.
1240 |
1241 |        (MMO3_TYPEBITS)
1242 |        0xf  - We have a complete symbol; parse the type, value
1243 |               and serial number and do what should be done
1244 |               with a symbol.  The type and length information
1245 |               is in j = (m & 0xf).
1246 |
1247 |               (MMO3_REGQUAL_BITS)
1248 |               j == 0xf: A register variable.  The following
1249 |                         byte tells which register.
1250 |               j <= 8:   An absolute symbol.  Read j bytes as the
1251 |                         big-endian number the symbol equals.
1252 |                         A j = 2 with two zero bytes denotes an
1253 |                         unknown symbol.
1254 |               j > 8:    As with j <= 8, but add (0x20 << 56)
1255 |                         to the value in the following j - 8
1256 |                         bytes.
1257 |
1258 |               Then comes the serial number, as a variant of
1259 |               uleb128, but better named ubeb128:
1260 |               Read bytes and shift the previous value left 7
1261 |               (multiply by 128).  Add in the new byte, repeat
1262 |               until a byte has bit 7 set.  The serial number
1263 |               is the computed value minus 128.
1264 |
1265 |        (MMO3_MIDDLE)
1266 |        0x20 - Traverse middle trie.  (Read a new command byte
1267 |               and recurse.)  Decrement character position.
1268 |
1269 | (MMO3_RIGHT)
1270 | 0x10 - Traverse right trie.  (Read a new command byte and
1271 |        recurse.)
1272
1273         Let's look again at the <<lop_stab>> for the trivial file
1274         (@pxref{File layout}).
1275
1276 | 0x980b0000 - lop_stab for ":Main" = 0, serial 1.
1277 | 0x203a4040
1278 | 0x10404020
1279 | 0x4d206120
1280 | 0x69016e00
1281 | 0x81000000
1282
1283         This forms the trivial trie (note that the path between ``:'' and
1284         ``M'' is redundant):
1285
1286 | 203a     ":"
1287 | 40       /
1288 | 40      /
1289 | 10      \
1290 | 40      /
1291 | 40     /
1292 | 204d  "M"
1293 | 2061  "a"
1294 | 2069  "i"
1295 | 016e  "n" is the last character in a full symbol, and
1296 |       with a value represented in one byte.
1297 | 00    The value is 0.
1298 | 81    The serial number is 1.  */
1299
1300   bfd_byte m = mmo_get_byte (abfd);
1301
1302   /* Check first if we have a bad hair day.  */
1303   if (abfd->tdata.mmo_data->have_error)
1304     return FALSE;
1305
1306   if (m & MMO3_LEFT)
1307     /* Traverse left trie. */
1308     mmo_get_symbols (abfd);
1309
1310   if (m & MMO3_SYMBITS)
1311     {
1312       bfd_byte c = mmo_get_byte (abfd);
1313       bfd_byte j = m & MMO3_TYPEBITS;
1314       bfd_vma addr = 0;
1315       enum mmo_sym_type sym_type;
1316       unsigned int serno = 0;
1317       bfd_byte k;
1318
1319       if (m & MMO3_WCHAR)
1320         {
1321           bfd_byte c2 = mmo_get_byte (abfd);
1322
1323           /* A two-byte character.  We can't grok this, but neither can
1324              mmotype, for other cases than the second byte being zero.  */
1325
1326           if (c != 0)
1327             {
1328               abfd->tdata.mmo_data->lop_stab_symbol
1329                 [abfd->tdata.mmo_data->symbol_position] = 0;
1330
1331               (*_bfd_error_handler)
1332                 (_("%s: unsupported wide character sequence"
1333                    " 0x%02X 0x%02X after symbol name starting with `%s'\n"),
1334                  bfd_get_filename (abfd), c, c2,
1335                  abfd->tdata.mmo_data->lop_stab_symbol);
1336               bfd_set_error (bfd_error_bad_value);
1337               abfd->tdata.mmo_data->have_error = TRUE;
1338               return FALSE;
1339             }
1340           else
1341             c = c2;
1342         }
1343
1344       abfd->tdata.mmo_data->lop_stab_symbol[abfd->tdata.mmo_data->symbol_position++] = c;
1345       abfd->tdata.mmo_data->lop_stab_symbol[abfd->tdata.mmo_data->symbol_position] = 0;
1346
1347       if (j & MMO3_REGQUAL_BITS)
1348         {
1349           if (j == MMO3_REGQUAL_BITS)
1350             {
1351               sym_type = mmo_reg_sym;
1352               addr = mmo_get_byte (abfd);
1353             }
1354           else if (j <= 8)
1355             {
1356               unsigned int i;
1357
1358               for (i = 0; i < j; i++)
1359                 addr = (addr << 8) + mmo_get_byte (abfd);
1360
1361               if (addr == 0 && j == MMO3_UNDEF)
1362                 sym_type = mmo_undef_sym;
1363               else
1364                 sym_type = mmo_abs_sym;
1365             }
1366           else
1367             {
1368               unsigned int i;
1369
1370               for (i = MMO3_DATA; i < j; i++)
1371                 addr = (addr << 8) + mmo_get_byte (abfd);
1372
1373               addr += (bfd_vma) 0x20 << 56;
1374               sym_type = mmo_data_sym;
1375             }
1376
1377           /* Get the serial number.  */
1378           do
1379             {
1380               k = mmo_get_byte (abfd);
1381               serno = (serno << 7) + k;
1382             }
1383           while (k < 128);
1384           serno -= 128;
1385
1386           /* Got it.  Now enter it.  Skip a leading ":".  */
1387           if (! abfd->tdata.mmo_data->have_error
1388               && ! mmo_create_symbol (abfd,
1389                                       abfd->tdata.mmo_data->lop_stab_symbol
1390                                       + 1,
1391                                       addr, sym_type, serno))
1392             abfd->tdata.mmo_data->have_error = TRUE;
1393         }
1394
1395       if (m & MMO3_MIDDLE)
1396         /* Traverse middle trie. */
1397         mmo_get_symbols (abfd);
1398
1399       abfd->tdata.mmo_data->symbol_position--;
1400     }
1401
1402   if (m & MMO3_RIGHT)
1403     /* Traverse right trie.  */
1404     mmo_get_symbols (abfd);
1405
1406   return ! abfd->tdata.mmo_data->have_error;
1407 }
1408
1409 /* Get the location of memory area [VMA..VMA + SIZE - 1], which we think
1410    is in section SEC.  Adjust and reallocate zero-initialized contents.
1411    If there's new contents, allocate to the next multiple of
1412    MMO_SEC_CONTENTS_CHUNK_SIZE.  */
1413
1414 static INLINE bfd_byte *
1415 mmo_get_loc (asection *sec, bfd_vma vma, int size)
1416 {
1417   bfd_size_type allocated_size;
1418   struct mmo_section_data_struct *sdatap = mmo_section_data (sec);
1419   struct mmo_data_list_struct *datap = sdatap->head;
1420   struct mmo_data_list_struct *entry;
1421
1422   /* First search the list to see if we have the requested chunk in one
1423      piece, or perhaps if we have a suitable chunk with room to fit.  */
1424   for (; datap != NULL; datap = datap->next)
1425     {
1426       if (datap->where <= vma
1427           && datap->where + datap->size >= vma + size)
1428         return datap->data + vma - datap->where;
1429       else if (datap->where <= vma
1430                && datap->where + datap->allocated_size >= vma + size
1431                /* Only munch on the "allocated size" if it does not
1432                   overlap the next chunk.  */
1433                && (datap->next == NULL || datap->next->where >= vma + size))
1434         {
1435           /* There was room allocated, but the size wasn't set to include
1436              it.  Do that now.  */
1437           datap->size += (vma + size) - (datap->where + datap->size);
1438
1439           /* Update the section size.  This happens only if we update the
1440              32-bit-aligned chunk size.  Callers that have
1441              non-32-bit-aligned sections should do all allocation and
1442              size-setting by themselves or at least set the section size
1443              after the last allocating call to this function.  */
1444           if (vma + size > sec->vma + sec->size)
1445             sec->size += (vma + size) - (sec->vma + sec->size);
1446
1447           return datap->data + vma - datap->where;
1448         }
1449     }
1450
1451   /* Not found; allocate a new block.  First check in case we get a
1452      request for a size split up over several blocks; we'll have to return
1453      NULL for those cases, requesting the caller to split up the request.
1454      Requests with an address aligned on MMO_SEC_CONTENTS_CHUNK_SIZE bytes and
1455      for no more than MMO_SEC_CONTENTS_CHUNK_SIZE will always get resolved.  */
1456
1457   for (datap = sdatap->head; datap != NULL; datap = datap->next)
1458     if ((datap->where <= vma && datap->where + datap->size > vma)
1459         || (datap->where < vma + size
1460             && datap->where + datap->size >= vma + size))
1461       return NULL;
1462
1463   allocated_size
1464     = (size + MMO_SEC_CONTENTS_CHUNK_SIZE - 1) & ~(MMO_SEC_CONTENTS_CHUNK_SIZE - 1);
1465   entry = (mmo_data_list_type *)
1466     bfd_zalloc (sec->owner, sizeof (mmo_data_list_type) + allocated_size);
1467   if (entry == NULL)
1468     return NULL;
1469   entry->where = vma;
1470   entry->size = size;
1471   entry->allocated_size = allocated_size;
1472
1473   datap = sdatap->head;
1474
1475   /* Sort the records by address.  Optimize for the common case of adding
1476      a record to the end of the list.  */
1477   if (sdatap->tail != NULL && entry->where >= sdatap->tail->where)
1478     {
1479       sdatap->tail->next = entry;
1480       entry->next = NULL;
1481       sdatap->tail = entry;
1482     }
1483   else
1484     {
1485       mmo_data_list_type **look;
1486       for (look = &sdatap->head;
1487            *look != NULL && (*look)->where < entry->where;
1488            look = &(*look)->next)
1489         ;
1490       entry->next = *look;
1491       *look = entry;
1492       if (entry->next == NULL)
1493         {
1494           sdatap->tail = entry;
1495
1496           /* We get here for the first time (at other times too) for this
1497              section.  Say we have contents.  */
1498           if (! bfd_set_section_flags (sec->owner, sec,
1499                                        bfd_get_section_flags (sec->owner, sec)
1500                                        | SEC_HAS_CONTENTS))
1501             return NULL;
1502         }
1503     }
1504
1505   /* Update the section size.  This happens only when we add contents and
1506      re-size as we go.  The section size will then be aligned to 32 bits.  */
1507   if (vma + size > sec->vma + sec->size)
1508     sec->size += (vma + size) - (sec->vma + sec->size);
1509   return entry->data;
1510 }
1511
1512 /* Set sizes once we've read in all sections.  */
1513
1514 static void
1515 mmo_map_set_sizes (bfd *abfd ATTRIBUTE_UNUSED, asection *sec,
1516                    void *ignored ATTRIBUTE_UNUSED)
1517 {
1518   sec->lma = sec->vma;
1519 }
1520
1521 /* Read the mmo file and turn it into sections.  */
1522
1523 static bfd_boolean
1524 mmo_scan (bfd *abfd)
1525 {
1526   unsigned int i;
1527   unsigned int lineno = 1;
1528   bfd_boolean error = FALSE;
1529   bfd_vma vma = 0;
1530   asection *sec = bfd_make_section_old_way (abfd, MMO_TEXT_SECTION_NAME);
1531   asection *non_spec_sec = NULL;
1532   bfd_vma non_spec_vma = 0;
1533   char *current_filename = NULL;
1534   bfd_size_type nbytes_read = 0;
1535   /* Buffer with room to read a 64-bit value.  */
1536   bfd_byte buf[8];
1537   long stab_loc = -1;
1538   char *file_names[256];
1539
1540   memset (file_names, 0, sizeof (file_names));
1541
1542   if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0)
1543     goto error_return;
1544
1545   while ((nbytes_read = bfd_bread (buf, 4, abfd)) == 4)
1546     {
1547       if (buf[0] == LOP)
1548         {
1549           unsigned int y = bfd_get_8 (abfd, buf + 2);
1550           unsigned int z = bfd_get_8 (abfd, buf + 3);
1551
1552           /* Change back to the original section for lopcodes other
1553              than LOP_QUOTE that comes after a LOP_SPEC.  */
1554           if ((buf[1] != LOP_QUOTE || y != 0 || z != 1)
1555               && non_spec_sec != NULL)
1556             {
1557               sec = non_spec_sec;
1558               vma = non_spec_vma;
1559               non_spec_sec = NULL;
1560             }
1561
1562           switch (buf[1])
1563             {
1564             default:
1565               (*_bfd_error_handler)
1566                 (_("%s: invalid mmo file: unsupported lopcode `%d'\n"),
1567                  bfd_get_filename (abfd), buf[1]);
1568               bfd_set_error (bfd_error_bad_value);
1569               goto error_return;
1570
1571             case LOP_QUOTE:
1572               /* Quote the next 32-bit word.  */
1573               if (y != 0 || z != 1)
1574                 {
1575                   (*_bfd_error_handler)
1576                     (_("%s: invalid mmo file: expected YZ = 1 got YZ = %d for lop_quote\n"),
1577                      bfd_get_filename (abfd), y*256+z);
1578                   bfd_set_error (bfd_error_bad_value);
1579                   goto error_return;
1580                 }
1581               if (bfd_bread (buf, 4, abfd) != 4)
1582                 goto error_return;
1583
1584               mmo_xore_32 (sec, vma, bfd_get_32 (abfd, buf));
1585               vma += 4;
1586               vma &= ~3;
1587               lineno++;
1588               break;
1589
1590             case LOP_LOC:
1591               /* Set vma (and section).  */
1592               vma = (bfd_vma) y << 56;
1593               if (z == 1)
1594                 {
1595                   /* Get a 32-bit value.  */
1596                   if (bfd_bread (buf, 4, abfd) != 4)
1597                     goto error_return;
1598
1599                   vma += bfd_get_32 (abfd, buf);
1600                 }
1601               else if (z == 2)
1602                 {
1603                   /* Get a 64-bit value.  */
1604                   if (bfd_bread (buf, 8, abfd) != 8)
1605                     goto error_return;
1606
1607                   vma += bfd_get_64 (abfd, buf);
1608                 }
1609               else
1610                 {
1611                   (*_bfd_error_handler)
1612                     (_("%s: invalid mmo file: expected z = 1 or z = 2, got z = %d for lop_loc\n"),
1613                      bfd_get_filename (abfd), z);
1614                   bfd_set_error (bfd_error_bad_value);
1615                   goto error_return;
1616                 }
1617
1618               sec = mmo_decide_section (abfd, vma);
1619               if (sec == NULL)
1620                 goto error_return;
1621               break;
1622
1623             case LOP_SKIP:
1624               /* Move forward within the same section.  */
1625               vma += y * 256 + z;
1626
1627               sec = mmo_decide_section (abfd, vma);
1628               if (sec == NULL)
1629                 goto error_return;
1630               break;
1631
1632             case LOP_FIXO:
1633               /* A fixup: Store the current vma somewhere.  Position using
1634                  same format as LOP_LOC.  */
1635               {
1636                 bfd_vma p = (bfd_vma) y << 56;
1637                 asection *fixosec;
1638
1639                 if (z == 1)
1640                   {
1641                     /* Get a 32-bit value.  */
1642                     if (bfd_bread (buf, 4, abfd) != 4)
1643                       goto error_return;
1644
1645                     p += bfd_get_32 (abfd, buf);
1646                   }
1647                 else if (z == 2)
1648                   {
1649                     /* Get a 64-bit value.  */
1650                     if (bfd_bread (buf, 8, abfd) != 8)
1651                       goto error_return;
1652
1653                     p += bfd_get_64 (abfd, buf);
1654                   }
1655                 else
1656                   {
1657                     (*_bfd_error_handler)
1658                       (_("%s: invalid mmo file: expected z = 1 or z = 2, got z = %d for lop_fixo\n"),
1659                        bfd_get_filename (abfd), z);
1660                     bfd_set_error (bfd_error_bad_value);
1661                     goto error_return;
1662                   }
1663
1664                 /* The section where we store this address might be a
1665                    different one than the current section.  */
1666                 fixosec = mmo_decide_section (abfd, p);
1667                 if (fixosec == NULL)
1668                   goto error_return;
1669                 mmo_xore_64 (fixosec, p, vma);
1670               }
1671             break;
1672
1673             case LOP_FIXR:
1674               /* A fixup: Store YZ of this lopcode into YZ at vma - 4 * yz.  */
1675               {
1676                 unsigned int yz = (y * 256 + z);
1677                 bfd_vma p = vma + 2 - 4 * yz;
1678                 asection *fixrsec = mmo_decide_section (abfd, p);
1679                 if (fixrsec == NULL)
1680                   goto error_return;
1681                 mmo_xore_16 (fixrsec, p, yz);
1682               }
1683             break;
1684
1685             case LOP_FIXRX:
1686               /* A fixup, similar to lop_fixr, but taking larger numbers
1687                  and can change branches into the opposite direction
1688                  (gasp!).  */
1689               {
1690                 bfd_vma delta;
1691                 bfd_vma p;
1692                 asection *fixrsec;
1693
1694                 if (y != 0)
1695                   {
1696                     (*_bfd_error_handler)
1697                       (_("%s: invalid mmo file: expected y = 0, got y = %d for lop_fixrx\n"),
1698                        bfd_get_filename (abfd), y);
1699                     bfd_set_error (bfd_error_bad_value);
1700                     goto error_return;
1701                   }
1702
1703                 if (z != 16 && z != 24)
1704                   {
1705                     (*_bfd_error_handler)
1706                       (_("%s: invalid mmo file: expected z = 16 or z = 24, got z = %d for lop_fixrx\n"),
1707                        bfd_get_filename (abfd), z);
1708                     bfd_set_error (bfd_error_bad_value);
1709                     goto error_return;
1710                   }
1711
1712                 /* Get the next 32-bit value.  */
1713                 if (bfd_bread (buf, 4, abfd) != 4)
1714                   goto error_return;
1715
1716                 delta = bfd_get_32 (abfd, buf);
1717
1718                 /* Do an, ehm, involved calculation for the location of
1719                    the fixup.  See mmixal documentation for a verbose
1720                    explanation.  We follow it verbosely here for the
1721                    readers delight.  */
1722                 if (buf[0] == 0)
1723                   p = vma - 4 * delta;
1724                 else if (buf[0] == 1)
1725                   p = vma - 4 * ((delta & 0xffffff) - (1 << z));
1726                 else
1727                   {
1728                     (*_bfd_error_handler)
1729                       (_("%s: invalid mmo file: leading byte of operand word must be 0 or 1, got %d for lop_fixrx\n"),
1730                        bfd_get_filename (abfd), buf[0]);
1731                     bfd_set_error (bfd_error_bad_value);
1732                     goto error_return;
1733                   }
1734
1735                 fixrsec = mmo_decide_section (abfd, vma);
1736                 if (fixrsec == NULL)
1737                   goto error_return;
1738                 mmo_xore_32 (fixrsec, p, delta);
1739               }
1740             break;
1741
1742             case LOP_FILE:
1743               /* Set current file and perhaps the file name.  Reset line
1744                  number.  */
1745               if (z != 0)
1746                 {
1747                   char *fname = bfd_malloc (z * 4 + 1);
1748
1749                   if (fname == NULL)
1750                     {
1751                       (*_bfd_error_handler)
1752                         (_("%s: cannot allocate file name for file number %d, %d bytes\n"),
1753                          bfd_get_filename (abfd), y, z * 4 + 1);
1754                       bfd_set_error (bfd_error_system_call);
1755                       goto error_return;
1756                     }
1757
1758                   fname[z * 4] = 0;
1759
1760                   for (i = 0; i < z; i++)
1761                     {
1762                       if (bfd_bread (fname + i * 4, 4, abfd) != 4)
1763                         {
1764                           free (fname);
1765                           goto error_return;
1766                         }
1767                     }
1768
1769                   if (file_names[y] != NULL)
1770                     {
1771                       (*_bfd_error_handler)
1772                         (_("%s: invalid mmo file: file number %d `%s',"
1773                            " was already entered as `%s'\n"),
1774                          bfd_get_filename (abfd), y, fname, file_names[y]);
1775                       bfd_set_error (bfd_error_bad_value);
1776                       goto error_return;
1777                     }
1778
1779                   file_names[y] = fname;
1780                 }
1781
1782               if (file_names[y] == NULL)
1783                 {
1784                   (*_bfd_error_handler)
1785                     (_("%s: invalid mmo file: file name for number %d"
1786                        " was not specified before use\n"),
1787                      bfd_get_filename (abfd), y);
1788                   bfd_set_error (bfd_error_bad_value);
1789                   goto error_return;
1790                 }
1791
1792               current_filename = file_names[y];
1793               lineno = 0;
1794               break;
1795
1796             case LOP_LINE:
1797               /* Set line number.  */
1798               lineno = y * 256 + z;
1799               /* FIXME: Create a sequence of mmo-specific line number
1800                  entries for each section, then translate into canonical
1801                  format.  */
1802               break;
1803
1804             case LOP_SPEC:
1805               /* Special data follows until the next non-lop_quote
1806                  lopcode.  */
1807               non_spec_sec = sec;
1808               non_spec_vma = vma;
1809               sec = mmo_get_spec_section (abfd, y * 256 + z);
1810               if (sec == NULL)
1811                 goto error_return;
1812
1813               vma = sec->vma;
1814               break;
1815
1816             case LOP_PRE:
1817               {
1818                 /* We ignore header information, except we read in the
1819                    creation time from the first 32-bit word with the time
1820                    in seconds since era.  */
1821                 if (z >= 1
1822                     && bfd_bread (abfd->tdata.mmo_data->created, 4,
1823                                  abfd) != 4)
1824                   goto error_return;
1825
1826                 for (i = 1; i < z; i++)
1827                   if (bfd_bread (buf, 4, abfd) != 4)
1828                     goto error_return;
1829               }
1830               break;
1831
1832             case LOP_POST:
1833               /* This tells of the contents of registers $Z..$255 at
1834                  startup.  We make a section out of it, with VMA = Z * 8,
1835                  but only if Z != 255 or the contents is non-zero.  */
1836               {
1837                 asection *rsec;
1838                 bfd_byte *loc;
1839                 bfd_vma first_octa;
1840                 bfd_vma startaddr_octa;
1841
1842                 /* Read first octaword outside loop to simplify logic when
1843                    excluding the Z == 255, octa == 0 case.  */
1844                 if (bfd_bread (buf, 8, abfd) != 8)
1845                   goto error_return;
1846
1847                 first_octa = bfd_get_64 (abfd, buf);
1848
1849                 /* Don't emit contents for the trivial case which is
1850                    always present; $255 pointing to Main.  */
1851                 if (z != 255)
1852                   {
1853                     rsec
1854                       = bfd_make_section_old_way (abfd,
1855                                                   MMIX_REG_CONTENTS_SECTION_NAME);
1856                     rsec->vma = z * 8;
1857                     loc = mmo_get_loc (rsec, z * 8, (255 - z) * 8);
1858                     bfd_put_64 (abfd, first_octa, loc);
1859
1860                     for (i = z + 1; i < 255; i++)
1861                       {
1862                         if (bfd_bread (loc + (i - z) * 8, 8, abfd) != 8)
1863                           goto error_return;
1864                       }
1865
1866                     /* Read out the last octabyte, and use it to set the
1867                        start address.  */
1868                     if (bfd_bread (buf, 8, abfd) != 8)
1869                       goto error_return;
1870
1871                     startaddr_octa = bfd_get_64 (abfd, buf);
1872                   }
1873                 else
1874                   startaddr_octa = first_octa;
1875
1876                 if (! bfd_set_start_address (abfd, startaddr_octa))
1877                   {
1878                     /* Currently this can't fail, but this should handle
1879                        future failures.  */
1880                     bfd_set_error (bfd_error_bad_value);
1881                     goto error_return;
1882                   }
1883               }
1884               break;
1885
1886             case LOP_STAB:
1887               /* We read in the symbols now, not later.  */
1888               if (y != 0 || z != 0)
1889                 {
1890                   (*_bfd_error_handler)
1891                     (_("%s: invalid mmo file: fields y and z of lop_stab"
1892                        " non-zero, y: %d, z: %d\n"),
1893                      bfd_get_filename (abfd), y, z);
1894                   bfd_set_error (bfd_error_bad_value);
1895                   goto error_return;
1896                 }
1897
1898               /* Save the location, so we can check that YZ in the LOP_END
1899                  is correct.  */
1900               stab_loc = bfd_tell (abfd);
1901
1902               /* It's not said that an MMO can be without symbols (though
1903                  mmixal will refuse to assemble files without Main), but
1904                  it seems it would still be a valid mmo-file, so allow it.
1905                  We detect the absence of a symbol area in that the upper
1906                  limit is computed (from the lop_end YZ field) as 0.
1907                  Don't call mmo_get_symbols; it can only detect the end of
1908                  a valid symbol trie, not the absence of one.  */
1909               if (abfd->tdata.mmo_data->max_symbol_length != 0
1910                   && ! mmo_get_symbols (abfd))
1911                 goto error_return;
1912               break;
1913
1914             case LOP_END:
1915               {
1916                 /* This must be the last 32-bit word in an mmo file.
1917                    Let's find out.  */
1918                 struct stat statbuf;
1919                 long curpos = bfd_tell (abfd);
1920
1921                 if (bfd_stat (abfd, &statbuf) < 0)
1922                   goto error_return;
1923
1924                 if (statbuf.st_size != curpos)
1925                   {
1926                     (*_bfd_error_handler)
1927                       (_("%s: invalid mmo file: lop_end not last item in"
1928                          " file\n"),
1929                        bfd_get_filename (abfd));
1930                     bfd_set_error (bfd_error_bad_value);
1931                     goto error_return;
1932                   }
1933
1934                 /* Check that the YZ field is right.  Subtract the size of
1935                    this LOP_END in the calculation; YZ does not include
1936                    it.  */
1937                 if ((long) (y * 256 + z) * 4 != (curpos - stab_loc) - 4)
1938                   {
1939                     (*_bfd_error_handler)
1940                       (_("%s: invalid mmo file: YZ of lop_end (%ld)"
1941                          " not equal to the number of tetras to the preceding"
1942                          " lop_stab (%ld)\n"),
1943                        bfd_get_filename (abfd), (long) (y * 256 + z),
1944                        (curpos - stab_loc - 4)/4);
1945                     bfd_set_error (bfd_error_bad_value);
1946                     goto error_return;
1947                   }
1948
1949                 bfd_map_over_sections (abfd, mmo_map_set_sizes, NULL);
1950                 goto done;
1951               }
1952             }
1953         }
1954       else
1955         {
1956           /* This wasn't a lopcode, so store it in the current section.  */
1957           mmo_xore_32 (sec, vma & ~3, bfd_get_32 (abfd, buf));
1958           vma += 4;
1959           vma &= ~3;
1960           lineno++;
1961         }
1962     }
1963
1964   /* We know this file is a multiple of four bytes (checked in
1965      mmo_object_p), so if we got something other than 0, this was a bad
1966      file (although it's more likely we'll get 0 in that case too).
1967      If we got end-of-file, then there was no lop_stab, so the file has
1968      invalid format.  */
1969
1970   if (nbytes_read != 0)
1971     bfd_set_error (bfd_error_system_call);
1972   else
1973     bfd_set_error (bfd_error_bad_value);
1974
1975  error_return:
1976   error = TRUE;
1977  done:
1978   /* Mark the .text and .data section with their normal attribute if they
1979      contain anything.  This is not redundant wrt. mmo_decide_section,
1980      since that code might never execute, and conversely the alloc+code
1981      section flags must be set then.  */
1982   sec = bfd_get_section_by_name (abfd, MMO_TEXT_SECTION_NAME);
1983   if (sec != NULL
1984       && (bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS)
1985       && ! bfd_set_section_flags (abfd, sec,
1986                                   bfd_get_section_flags (abfd, sec)
1987                                   | SEC_ALLOC | SEC_LOAD | SEC_CODE))
1988     error = TRUE;
1989
1990   sec = bfd_get_section_by_name (abfd, MMO_DATA_SECTION_NAME);
1991   if (sec != NULL
1992       && (bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS)
1993       && ! bfd_set_section_flags (abfd, sec,
1994                                   bfd_get_section_flags (abfd, sec)
1995                                   | SEC_ALLOC | SEC_LOAD))
1996     error = TRUE;
1997
1998   /* Free whatever resources we took.  */
1999   for (i = 0; i < sizeof (file_names) / sizeof (file_names[0]); i++)
2000     if (file_names[i])
2001       free (file_names[i]);
2002   return ! error;
2003 }
2004
2005 /* A hook to set up object file dependent section information.  For mmo,
2006    we point out the shape of allocated section contents.  */
2007
2008 static bfd_boolean
2009 mmo_new_section_hook (bfd *abfd ATTRIBUTE_UNUSED, asection *newsect)
2010 {
2011   /* We zero-fill all fields and assume NULL is represented by an all
2012      zero-bit pattern.  */
2013   newsect->used_by_bfd =
2014     bfd_zalloc (abfd, sizeof (struct mmo_section_data_struct));
2015
2016   if (!newsect->used_by_bfd)
2017     return FALSE;
2018
2019   /* Always align to at least 32-bit words.  */
2020   newsect->alignment_power = 2;
2021   return TRUE;
2022 }
2023
2024 /* We already have section contents loaded for sections that have
2025    contents.  */
2026
2027 static bfd_boolean
2028 mmo_get_section_contents (bfd *abfd ATTRIBUTE_UNUSED,
2029                           asection *sec,
2030                           void * location,
2031                           file_ptr offset,
2032                           bfd_size_type bytes_to_do)
2033 {
2034   /* Iterate over diminishing chunk sizes, copying contents, like
2035      mmo_set_section_contents.  */
2036   while (bytes_to_do)
2037     {
2038       /* A minor song-and-dance to make sure we're not bitten by the
2039          distant possibility of the cast from bfd_vma to int making the
2040          chunk zero-sized.  */
2041       int chunk_size
2042         = (int) bytes_to_do != 0 ? bytes_to_do : MMO_SEC_CONTENTS_CHUNK_SIZE;
2043       bfd_byte *loc;
2044
2045       do
2046         loc = mmo_get_loc (sec, sec->vma + offset, chunk_size);
2047       while (loc == NULL && (chunk_size /= 2) != 0);
2048
2049       if (chunk_size == 0)
2050         return FALSE;
2051
2052       memcpy (location, loc, chunk_size);
2053
2054       location += chunk_size;
2055       bytes_to_do -= chunk_size;
2056       offset += chunk_size;
2057     }
2058   return TRUE;
2059 }
2060
2061 /* Return the amount of memory needed to read the symbol table.  */
2062
2063 static long
2064 mmo_get_symtab_upper_bound (bfd *abfd)
2065 {
2066   return (abfd->symcount + 1) * sizeof (asymbol *);
2067 }
2068
2069 /* Sort mmo symbols by serial number.  */
2070
2071 static int
2072 mmo_sort_mmo_symbols (const void *arg1, const void *arg2)
2073 {
2074   const struct mmo_symbol *sym1 = *(const struct mmo_symbol **) arg1;
2075   const struct mmo_symbol *sym2 = *(const struct mmo_symbol **) arg2;
2076
2077   /* Sort by serial number first.  */
2078   if (sym1->serno < sym2->serno)
2079     return -1;
2080   else if (sym1->serno > sym2->serno)
2081     return 1;
2082
2083   /* Then sort by address of the table entries.  */
2084   return ((const char *) arg1 - (const char *) arg2);
2085 }
2086
2087 /* Translate the symbol table.  */
2088
2089 static long
2090 mmo_canonicalize_symtab (bfd *abfd, asymbol **alocation)
2091 {
2092   unsigned int symcount = bfd_get_symcount (abfd);
2093   asymbol *csymbols;
2094   unsigned int i;
2095
2096   csymbols = abfd->tdata.mmo_data->csymbols;
2097   if (csymbols == NULL)
2098     {
2099       asymbol *c;
2100       struct mmo_symbol *s;
2101       struct mmo_symbol **msp;
2102
2103       /* First we store the symbols into the table we'll return, then we
2104          qsort it on the serial number, with secondary on the address of
2105          the symbol, to preserve order if there would be non-unique serial
2106          numbers.  */
2107       for (s = abfd->tdata.mmo_data->symbols,
2108              msp = (struct mmo_symbol **) alocation;
2109            s != NULL;
2110            s = s->next, ++msp)
2111         *msp = s;
2112
2113       *msp = NULL;
2114
2115       qsort (alocation, symcount, sizeof (struct mmo_symbol *),
2116              mmo_sort_mmo_symbols);
2117
2118       csymbols = (asymbol *) bfd_alloc (abfd, symcount * sizeof (asymbol));
2119       if (csymbols == NULL && symcount != 0)
2120         return FALSE;
2121       abfd->tdata.mmo_data->csymbols = csymbols;
2122
2123       for (msp = (struct mmo_symbol **) alocation, c = csymbols;
2124            *msp != NULL;
2125            msp++, ++c)
2126         {
2127           s = *msp;
2128           c->the_bfd = abfd;
2129           c->name = s->name;
2130           c->value = s->value;
2131           c->flags = BSF_GLOBAL;
2132
2133           if (s->sym_type == mmo_data_sym)
2134             {
2135               c->section
2136                 = bfd_get_section_by_name (abfd, MMO_DATA_SECTION_NAME);
2137
2138               if (c->section == NULL)
2139                 c->section = bfd_abs_section_ptr;
2140               else
2141                 c->value -= c->section->vma;
2142             }
2143           else if (s->sym_type == mmo_undef_sym)
2144             c->section = bfd_und_section_ptr;
2145           else if (s->sym_type == mmo_reg_sym)
2146             {
2147               c->section
2148                 = bfd_make_section_old_way (abfd, MMIX_REG_SECTION_NAME);
2149             }
2150           else
2151             {
2152               asection *textsec
2153                 = bfd_get_section_by_name (abfd, MMO_TEXT_SECTION_NAME);
2154               asection *datasec;
2155
2156               if (textsec != NULL
2157                   && c->value >= textsec->vma
2158                   && c->value <= textsec->vma + textsec->size)
2159                 {
2160                   c->section = textsec;
2161                   c->value -= c->section->vma;
2162                 }
2163               /* In mmo, symbol types depend on the VMA.  Therefore, if
2164                  the data section isn't within the usual bounds, its
2165                  symbols are marked as absolute.  Correct that.  This
2166                  means we can't have absolute symbols with values matching
2167                  data section addresses, but we also can't have with
2168                  absolute symbols with values matching text section
2169                  addresses.  For such needs, use the ELF format.  */
2170               else if ((datasec
2171                         = bfd_get_section_by_name (abfd,
2172                                                    MMO_DATA_SECTION_NAME))
2173                        != NULL
2174                        && c->value >= datasec->vma
2175                        && c->value <= datasec->vma + datasec->size)
2176                 {
2177                   c->section = datasec;
2178                   c->value -= c->section->vma;
2179                 }
2180               else
2181                 c->section = bfd_abs_section_ptr;
2182             }
2183
2184           c->udata.p = NULL;
2185         }
2186     }
2187
2188   /* Last, overwrite the incoming table with the right-type entries.  */
2189   for (i = 0; i < symcount; i++)
2190     *alocation++ = csymbols++;
2191   *alocation = NULL;
2192
2193   return symcount;
2194 }
2195
2196 /* Get information about a symbol.  */
2197
2198 static void
2199 mmo_get_symbol_info (bfd *ignore_abfd ATTRIBUTE_UNUSED,
2200                      asymbol *symbol, symbol_info *ret)
2201 {
2202   bfd_symbol_info (symbol, ret);
2203 }
2204
2205 static void
2206 mmo_print_symbol (bfd *abfd, void *afile, asymbol *symbol,
2207                   bfd_print_symbol_type how)
2208 {
2209   FILE *file = (FILE *) afile;
2210
2211   switch (how)
2212     {
2213     case bfd_print_symbol_name:
2214       fprintf (file, "%s", symbol->name);
2215       break;
2216     default:
2217       bfd_print_symbol_vandf (abfd, file, symbol);
2218
2219       fprintf (file, " %-5s %s",
2220                symbol->section->name,
2221                symbol->name);
2222     }
2223 }
2224
2225 /* We can't map a file directly into executable code, so the
2226    size of header information is irrelevant.  */
2227
2228 static int
2229 mmo_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED,
2230                     bfd_boolean exec ATTRIBUTE_UNUSED)
2231 {
2232   return 0;
2233 }
2234
2235 /* Write the (section-neutral) file preamble.  */
2236
2237 static bfd_boolean
2238 mmo_internal_write_header (bfd *abfd)
2239 {
2240   const char lop_pre_bfd[] = { LOP, LOP_PRE, 1, 1};
2241
2242   if (bfd_bwrite (lop_pre_bfd, 4, abfd) != 4)
2243     return FALSE;
2244
2245   /* Copy creation time of original file.  */
2246   if (bfd_bwrite (abfd->tdata.mmo_data->created, 4, abfd) != 4)
2247     return FALSE;
2248
2249   return TRUE;
2250 }
2251
2252 /* Write the LOP_POST record, with global register initializations.
2253    Z is the Z field of the LOP_POST, corresponding to 255 - number of
2254    registers at DATA.  The Z = 255 field is filled in with the
2255    start-address.  */
2256
2257 static bfd_boolean
2258 mmo_internal_write_post (bfd *abfd, int z, asection *sec)
2259 {
2260   int i;
2261   bfd_byte buf[8];
2262   mmo_write_tetra_raw (abfd, (LOP << 24) | (LOP_POST << 16) | z);
2263
2264   for (i = z; i < 255; i++)
2265     {
2266       bfd_byte *data = mmo_get_loc (sec, i * 8, 8);
2267
2268       if (bfd_bwrite (data, 8, abfd) != 8)
2269         return FALSE;
2270     }
2271
2272   /* For Z == $255, we always emit the start location; supposedly Main,
2273      but we have it handy at bfd_get_start_address.  If we're called with
2274      Z == 255, don't assume DATA is valid.  */
2275   bfd_put_64 (abfd, bfd_get_start_address (abfd), buf);
2276
2277   return ! abfd->tdata.mmo_data->have_error && bfd_bwrite (buf, 8, abfd) == 8;
2278 }
2279
2280 /* Translate to and from BFD flags.  This is to make sure that we don't
2281    get bitten by BFD flag number changes.  */
2282
2283 static flagword
2284 mmo_sec_flags_from_bfd_flags (flagword flags)
2285 {
2286   flagword oflags = 0;
2287
2288   if (flags & SEC_ALLOC)
2289     oflags |= MMO_SEC_ALLOC;
2290   if (flags & SEC_LOAD)
2291     oflags |= MMO_SEC_LOAD;
2292   if (flags & SEC_RELOC)
2293     oflags |= MMO_SEC_RELOC;
2294   if (flags & SEC_READONLY)
2295     oflags |= MMO_SEC_READONLY;
2296   if (flags & SEC_CODE)
2297     oflags |= MMO_SEC_CODE;
2298   if (flags & SEC_DATA)
2299     oflags |= MMO_SEC_DATA;
2300   if (flags & SEC_NEVER_LOAD)
2301     oflags |= MMO_SEC_NEVER_LOAD;
2302   if (flags & SEC_IS_COMMON)
2303     oflags |= MMO_SEC_IS_COMMON;
2304   if (flags & SEC_DEBUGGING)
2305     oflags |= MMO_SEC_DEBUGGING;
2306
2307   return oflags;
2308 }
2309
2310 static flagword
2311 bfd_sec_flags_from_mmo_flags (flagword flags)
2312 {
2313   flagword oflags = 0;
2314
2315   if (flags & MMO_SEC_ALLOC)
2316     oflags |= SEC_ALLOC;
2317   if (flags & MMO_SEC_LOAD)
2318     oflags |= SEC_LOAD;
2319   if (flags & MMO_SEC_RELOC)
2320     oflags |= SEC_RELOC;
2321   if (flags & MMO_SEC_READONLY)
2322     oflags |= SEC_READONLY;
2323   if (flags & MMO_SEC_CODE)
2324     oflags |= SEC_CODE;
2325   if (flags & MMO_SEC_DATA)
2326     oflags |= SEC_DATA;
2327   if (flags & MMO_SEC_NEVER_LOAD)
2328     oflags |= SEC_NEVER_LOAD;
2329   if (flags & MMO_SEC_IS_COMMON)
2330     oflags |= SEC_IS_COMMON;
2331   if (flags & MMO_SEC_DEBUGGING)
2332     oflags |= SEC_DEBUGGING;
2333
2334   return oflags;
2335 }
2336
2337 /* Return TRUE iff the leading or trailing tetrabyte in SEC is defined and
2338    is 0.  */
2339
2340 static bfd_boolean
2341 mmo_has_leading_or_trailing_zero_tetra_p (bfd *abfd, asection *sec)
2342 {
2343   bfd_vma secaddr = bfd_get_section_vma (abfd, sec);
2344
2345   if (sec->size < 4)
2346     return FALSE;
2347
2348   if (bfd_get_32 (abfd, mmo_get_loc (sec, secaddr, 4)) == 0
2349       && bfd_get_32 (abfd,
2350                      mmo_get_loc (sec, secaddr + sec->size - 4, 4)) == 0)
2351     return TRUE;
2352
2353   return FALSE;
2354 }
2355
2356 /* Write a section.  */
2357
2358 static bfd_boolean
2359 mmo_internal_write_section (bfd *abfd, asection *sec)
2360 {
2361   /* We do it differently depending on what section this is:
2362
2363    ".text": Output, prepended by information about the first source file
2364    (not yet implemented.)
2365
2366    ".data": Output.
2367
2368    (".MMIX.reg_contents": Not handled here.)
2369
2370    Anything else: Output inside a lop_spec 80, in the format described
2371    above.  */
2372
2373   if (strcmp (sec->name, MMO_TEXT_SECTION_NAME) == 0)
2374     {
2375       bfd_vma secaddr = bfd_get_section_vma (abfd, sec);
2376
2377       /* Because leading and trailing zeros are omitted in output, we need to
2378          specify the section boundaries so they're correct when the file
2379          is read in again.  That's also the case if this section is
2380          specified as not within its usual boundaries or alignments.  */
2381       if (sec->size != 0
2382           && (secaddr + sec->size >= (bfd_vma) 1 << 56
2383               || (secaddr & 3) != 0
2384               || (sec->size & 3) != 0
2385               || mmo_has_leading_or_trailing_zero_tetra_p (abfd, sec)))
2386         {
2387           if (!mmo_write_section_description (abfd, sec))
2388             return FALSE;
2389         }
2390
2391       /* FIXME: Output source file name and line number.  */
2392       return mmo_write_loc_chunk_list (abfd, mmo_section_data (sec)->head);
2393     }
2394   else if (strcmp (sec->name, MMO_DATA_SECTION_NAME) == 0)
2395     {
2396       bfd_vma secaddr = bfd_get_section_vma (abfd, sec);
2397
2398       /* Same goes as for MMO_TEXT_SECTION_NAME above.  */
2399       if (sec->size != 0
2400           && (secaddr < (bfd_vma) 0x20 << 56
2401               || secaddr + sec->size >= (bfd_vma) 0x21 << 56
2402               || (secaddr & 3) != 0
2403               || (sec->size & 3) != 0
2404               || mmo_has_leading_or_trailing_zero_tetra_p (abfd, sec)))
2405         {
2406           if (!mmo_write_section_description (abfd, sec))
2407             return FALSE;
2408         }
2409
2410       return mmo_write_loc_chunk_list (abfd, mmo_section_data (sec)->head);
2411     }
2412   else if (strcmp (sec->name, MMIX_REG_CONTENTS_SECTION_NAME) == 0)
2413     /* Not handled here.  */
2414     {
2415       /* This would normally be an abort call since this can't happen, but
2416          we don't do that.  */
2417       bfd_set_error (bfd_error_bad_value);
2418       return FALSE;
2419     }
2420   else if (strncmp (sec->name, MMIX_OTHER_SPEC_SECTION_PREFIX,
2421                     strlen (MMIX_OTHER_SPEC_SECTION_PREFIX)) == 0)
2422     {
2423       int n = atoi (sec->name + strlen (MMIX_OTHER_SPEC_SECTION_PREFIX));
2424       mmo_write_tetra_raw (abfd, (LOP << 24) | (LOP_SPEC << 16) | n);
2425       return (! abfd->tdata.mmo_data->have_error
2426               && mmo_write_chunk_list (abfd, mmo_section_data (sec)->head));
2427     }
2428   /* Ignore sections that are just allocated or empty; we write out
2429      _contents_ here.  */
2430   else if ((bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS) != 0
2431            && sec->size != 0)
2432     {
2433       if (!mmo_write_section_description (abfd, sec))
2434         return FALSE;
2435
2436       /* Writing a LOP_LOC ends the LOP_SPEC data, and makes data actually
2437          loaded.  */
2438       if (bfd_get_section_flags (abfd, sec) & SEC_LOAD)
2439         return (! abfd->tdata.mmo_data->have_error
2440                 && mmo_write_loc_chunk_list (abfd,
2441                                          mmo_section_data (sec)->head));
2442       return (! abfd->tdata.mmo_data->have_error
2443               && mmo_write_chunk_list (abfd, mmo_section_data (sec)->head));
2444     }
2445
2446   /* Some section without contents.  */
2447   return TRUE;
2448 }
2449
2450 /* Write the description of a section, extended-mmo-style.  */
2451
2452 static bfd_boolean
2453 mmo_write_section_description (bfd *abfd, asection *sec)
2454 {
2455   /* Keep the following document-comment formatted the way it is.  */
2456 /*
2457 INODE
2458 mmo section mapping, , Symbol-table, mmo
2459 SUBSECTION
2460         mmo section mapping
2461
2462         The implementation in BFD uses special data type 80 (decimal) to
2463         encapsulate and describe named sections, containing e.g.@: debug
2464         information.  If needed, any datum in the encapsulation will be
2465         quoted using lop_quote.  First comes a 32-bit word holding the
2466         number of 32-bit words containing the zero-terminated zero-padded
2467         segment name.  After the name there's a 32-bit word holding flags
2468         describing the section type.  Then comes a 64-bit big-endian word
2469         with the section length (in bytes), then another with the section
2470         start address.  Depending on the type of section, the contents
2471         might follow, zero-padded to 32-bit boundary.  For a loadable
2472         section (such as data or code), the contents might follow at some
2473         later point, not necessarily immediately, as a lop_loc with the
2474         same start address as in the section description, followed by the
2475         contents.  This in effect forms a descriptor that must be emitted
2476         before the actual contents.  Sections described this way must not
2477         overlap.
2478
2479         For areas that don't have such descriptors, synthetic sections are
2480         formed by BFD.  Consecutive contents in the two memory areas
2481         @samp{0x0000@dots{}00} to @samp{0x01ff@dots{}ff} and
2482         @samp{0x2000@dots{}00} to @samp{0x20ff@dots{}ff} are entered in
2483         sections named <<.text>> and <<.data>> respectively.  If an area
2484         is not otherwise described, but would together with a neighboring
2485         lower area be less than @samp{0x40000000} bytes long, it is joined
2486         with the lower area and the gap is zero-filled.  For other cases,
2487         a new section is formed, named <<.MMIX.sec.@var{n}>>.  Here,
2488         @var{n} is a number, a running count through the mmo file,
2489         starting at 0.
2490
2491 EXAMPLE
2492         A loadable section specified as:
2493
2494 | .section secname,"ax"
2495 | TETRA 1,2,3,4,-1,-2009
2496 | BYTE 80
2497
2498         and linked to address @samp{0x4}, is represented by the sequence:
2499
2500 | 0x98080050 - lop_spec 80
2501 | 0x00000002 - two 32-bit words for the section name
2502 | 0x7365636e - "secn"
2503 | 0x616d6500 - "ame\0"
2504 | 0x00000033 - flags CODE, READONLY, LOAD, ALLOC
2505 | 0x00000000 - high 32 bits of section length
2506 | 0x0000001c - section length is 28 bytes; 6 * 4 + 1 + alignment to 32 bits
2507 | 0x00000000 - high 32 bits of section address
2508 | 0x00000004 - section address is 4
2509 | 0x98010002 - 64 bits with address of following data
2510 | 0x00000000 - high 32 bits of address
2511 | 0x00000004 - low 32 bits: data starts at address 4
2512 | 0x00000001 - 1
2513 | 0x00000002 - 2
2514 | 0x00000003 - 3
2515 | 0x00000004 - 4
2516 | 0xffffffff - -1
2517 | 0xfffff827 - -2009
2518 | 0x50000000 - 80 as a byte, padded with zeros.
2519
2520         Note that the lop_spec wrapping does not include the section
2521         contents.  Compare this to a non-loaded section specified as:
2522
2523 | .section thirdsec
2524 | TETRA 200001,100002
2525 | BYTE 38,40
2526
2527         This, when linked to address @samp{0x200000000000001c}, is
2528         represented by:
2529
2530 | 0x98080050 - lop_spec 80
2531 | 0x00000002 - two 32-bit words for the section name
2532 | 0x7365636e - "thir"
2533 | 0x616d6500 - "dsec"
2534 | 0x00000010 - flag READONLY
2535 | 0x00000000 - high 32 bits of section length
2536 | 0x0000000c - section length is 12 bytes; 2 * 4 + 2 + alignment to 32 bits
2537 | 0x20000000 - high 32 bits of address
2538 | 0x0000001c - low 32 bits of address 0x200000000000001c
2539 | 0x00030d41 - 200001
2540 | 0x000186a2 - 100002
2541 | 0x26280000 - 38, 40 as bytes, padded with zeros
2542
2543         For the latter example, the section contents must not be
2544         loaded in memory, and is therefore specified as part of the
2545         special data.  The address is usually unimportant but might
2546         provide information for e.g.@: the DWARF 2 debugging format.  */
2547
2548   mmo_write_tetra_raw (abfd, LOP_SPEC_SECTION);
2549   mmo_write_tetra (abfd, (strlen (sec->name) + 3) / 4);
2550   mmo_write_chunk (abfd, (bfd_byte *) sec->name, strlen (sec->name));
2551   mmo_flush_chunk (abfd);
2552   /* FIXME: We can get debug sections (.debug_line & Co.) with a section
2553      flag still having SEC_RELOC set.  Investigate.  This might be true
2554      for all alien sections; perhaps mmo.em should clear that flag.  Might
2555      be related to weak references.  */
2556   mmo_write_tetra (abfd,
2557                    mmo_sec_flags_from_bfd_flags
2558                    (bfd_get_section_flags (abfd, sec)));
2559   mmo_write_octa (abfd, sec->size);
2560   mmo_write_octa (abfd, bfd_get_section_vma (abfd, sec));
2561   return TRUE;
2562 }
2563
2564 /* We save up all data before output.  */
2565
2566 static bfd_boolean
2567 mmo_set_section_contents (bfd *abfd ATTRIBUTE_UNUSED, sec_ptr sec,
2568                           const void *location, file_ptr offset,
2569                           bfd_size_type bytes_to_do)
2570 {
2571   /* Iterate over diminishing chunk sizes, copying contents.  */
2572   while (bytes_to_do)
2573     {
2574       /* A minor song-and-dance to make sure we're not bitten by the
2575          distant possibility of the cast from bfd_vma to int making the
2576          chunk zero-sized.  */
2577       int chunk_size
2578         = (int) bytes_to_do != 0 ? bytes_to_do : MMO_SEC_CONTENTS_CHUNK_SIZE;
2579       bfd_byte *loc;
2580
2581       do
2582         loc = mmo_get_loc (sec, sec->vma + offset, chunk_size);
2583       while (loc == NULL && (chunk_size /= 2) != 0);
2584
2585       if (chunk_size == 0)
2586         return FALSE;
2587
2588       memcpy (loc, location, chunk_size);
2589
2590       location += chunk_size;
2591       bytes_to_do -= chunk_size;
2592       offset += chunk_size;
2593     }
2594   return TRUE;
2595 }
2596
2597 /* Add a symbol to a trie-tree.  */
2598
2599 static bfd_boolean
2600 mmo_internal_add_3_sym (bfd *abfd, struct mmo_symbol_trie *rootp,
2601                         const struct mmo_symbol *symp)
2602 {
2603   const char *name = symp->name;
2604   struct mmo_symbol_trie *trie = rootp;
2605   struct mmo_symbol_trie **triep = NULL;
2606
2607   while (*name && trie != NULL)
2608     {
2609       if (*name < trie->symchar)
2610         {
2611           triep = &trie->left;
2612           trie = trie->left;
2613         }
2614       else if (*name > trie->symchar)
2615         {
2616           triep = &trie->right;
2617           trie = trie->right;
2618         }
2619       else if (*name == trie->symchar)
2620         {
2621           triep = &trie->middle;
2622           name++;
2623
2624           /* Make sure "trie" points to where we should fill in the
2625              current symbol whenever we've iterated through "name".  We
2626              would lose the right position if we encounter "foobar" then
2627              "foo".  */
2628           if (*name)
2629             trie = trie->middle;
2630         }
2631     }
2632
2633   while (*name != 0)
2634     {
2635       /* Create middle branches for the rest of the characters.  */
2636       trie = bfd_zalloc (abfd, sizeof (struct mmo_symbol_trie));
2637       *triep = trie;
2638       trie->symchar = *name++;
2639       triep = &trie->middle;
2640     }
2641
2642   /* We discover a duplicate symbol rather late in the process, but still;
2643      we discover it and bail out.  */
2644   if (trie->sym.name != NULL)
2645     {
2646       (*_bfd_error_handler)
2647         (_("%s: invalid symbol table: duplicate symbol `%s'\n"),
2648          bfd_get_filename (abfd), trie->sym.name);
2649       bfd_set_error (bfd_error_bad_value);
2650       return FALSE;
2651     }
2652
2653   memcpy (&trie->sym, symp, sizeof *symp);
2654   return TRUE;
2655 }
2656
2657 /* Find out the length of the serialized version of a trie in bytes.  */
2658
2659 static unsigned int
2660 mmo_internal_3_length (bfd *abfd, struct mmo_symbol_trie *trie)
2661 {
2662   /* First, one for the control byte.  */
2663   unsigned int length = 1;
2664
2665   if (trie == NULL)
2666     return 0;
2667
2668   /* Add in the recursion to the left.  */
2669   length += mmo_internal_3_length (abfd, trie->left);
2670
2671   /* Add in the middle trie and the character.  */
2672   length += 1 + mmo_internal_3_length (abfd, trie->middle);
2673
2674   /* Add in the recursion to the right.  */
2675   length += mmo_internal_3_length (abfd, trie->right);
2676
2677   /* Add in bytes for the symbol (if this is an endnode). */
2678   if (trie->sym.name != NULL)
2679     {
2680       unsigned int serno = trie->sym.serno;
2681
2682       /* First what it takes to encode the value. */
2683       if (trie->sym.sym_type == mmo_reg_sym)
2684         length++;
2685       else if (trie->sym.sym_type == mmo_undef_sym)
2686         length += 2;
2687       else
2688         {
2689           bfd_vma value = trie->sym.value;
2690
2691           /* Coded in one to eight following bytes.  */
2692           if (trie->sym.sym_type == mmo_data_sym)
2693             value -= (bfd_vma) 0x20 << 56;
2694
2695           do
2696             {
2697               value >>= 8;
2698               length++;
2699             }
2700           while (value != 0);
2701         }
2702
2703       /* Find out what it takes to encode the serial number.  */
2704       do
2705         {
2706           serno >>= 7;
2707           length++;
2708         }
2709       while (serno != 0);
2710     }
2711
2712   return length;
2713 }
2714
2715 /* Helper function for outputting the serial number of a symbol, output as
2716    a variant of leb128 (see dwarf2 documentation) which could be called
2717    beb128.  Using a helper function and recursion simplifies debugging.  */
2718
2719 static void
2720 mmo_beb128_out (bfd *abfd, int serno, int marker)
2721 {
2722   if (serno & ~0x7f)
2723     mmo_beb128_out (abfd, serno >> 7, 0);
2724   mmo_write_byte (abfd, marker | (serno & 0x7f));
2725 }
2726
2727 /* Serialize a trie.  */
2728
2729 static void
2730 mmo_internal_3_dump (bfd *abfd, struct mmo_symbol_trie *trie)
2731 {
2732   bfd_byte control = 0;
2733
2734   if (trie == NULL)
2735     return;
2736
2737   if (trie->left)
2738     control |= MMO3_LEFT;
2739
2740   if (trie->middle)
2741     control |= MMO3_MIDDLE;
2742
2743   if (trie->right)
2744     control |= MMO3_RIGHT;
2745
2746   if (trie->sym.name != NULL)
2747     {
2748       /* Encode the symbol type and length of value bytes.  */
2749       if (trie->sym.sym_type == mmo_reg_sym)
2750         control |= MMO3_REGQUAL_BITS;
2751       else if (trie->sym.sym_type == mmo_undef_sym)
2752         control |= MMO3_UNDEF;
2753       else
2754         {
2755           bfd_vma value = trie->sym.value;
2756
2757           /* Coded in 1..8 following bytes.  */
2758           if (trie->sym.sym_type == mmo_data_sym)
2759             {
2760               control |= MMO3_DATA;
2761               value -= (bfd_vma) 0x20 << 56;
2762             }
2763
2764           do
2765             {
2766               value >>= 8;
2767               control++;
2768             }
2769           while (value != 0);
2770         }
2771     }
2772
2773   /* The control byte is output before recursing.  */
2774   mmo_write_byte (abfd, control);
2775
2776   mmo_internal_3_dump (abfd, trie->left);
2777
2778   if (control & MMO3_SYMBITS)
2779     {
2780       mmo_write_byte (abfd, trie->symchar);
2781
2782       if (trie->sym.name != NULL)
2783         {
2784           if (trie->sym.sym_type == mmo_reg_sym)
2785             mmo_write_byte (abfd, trie->sym.value);
2786           else if (trie->sym.sym_type == mmo_undef_sym)
2787             {
2788               mmo_write_byte (abfd, 0);
2789               mmo_write_byte (abfd, 0);
2790             }
2791           else
2792             {
2793               bfd_vma value = trie->sym.value;
2794
2795               bfd_byte byte_n = control & 15;
2796
2797               /* Coded in 1..8 following bytes.  Note that the value is
2798                  shifted out big-endian.  */
2799               if (trie->sym.sym_type == mmo_data_sym)
2800                 {
2801                   value -= (bfd_vma) 0x20 << 56;
2802                   byte_n -= 8;
2803                 }
2804
2805               do
2806                 {
2807                   mmo_write_byte (abfd, (value >> ((byte_n - 1) * 8)) & 0xff);
2808                   byte_n--;
2809                 }
2810               while (byte_n != 0);
2811             }
2812
2813           mmo_beb128_out (abfd, trie->sym.serno, 128);
2814         }
2815       mmo_internal_3_dump (abfd, trie->middle);
2816     }
2817   mmo_internal_3_dump (abfd, trie->right);
2818 }
2819
2820 /* Write symbols in mmo format.  Also write the lop_end terminator.  */
2821
2822 static bfd_boolean
2823 mmo_write_symbols_and_terminator (bfd *abfd)
2824 {
2825   int count = bfd_get_symcount (abfd);
2826   asymbol *maintable[2];
2827   asymbol **table;
2828   asymbol **orig_table = bfd_get_outsymbols (abfd);
2829   int serno;
2830   struct mmo_symbol_trie root;
2831   int trie_len;
2832   int i;
2833   bfd_byte buf[4];
2834
2835   /* Create a symbol for "Main".  */
2836   asymbol *fakemain = bfd_make_empty_symbol (abfd);
2837
2838   fakemain->flags = BSF_GLOBAL;
2839   fakemain->value = bfd_get_start_address (abfd);
2840   fakemain->name = MMIX_START_SYMBOL_NAME;
2841   fakemain->section = bfd_abs_section_ptr;
2842   maintable[0] = fakemain;
2843   maintable[1] = NULL;
2844
2845   memset (&root, 0, sizeof (root));
2846
2847   /* Make all symbols take a left turn.  */
2848   root.symchar = 0xff;
2849
2850   /* There must always be a ":Main", so we'll add one if there are no
2851      symbols.  Make sure we have room for it.  */
2852   table = bfd_alloc (abfd, (count + 1) * sizeof (asymbol *));
2853   if (table == NULL)
2854     return FALSE;
2855
2856   memcpy (table, orig_table, count * sizeof (asymbol *));
2857
2858   /* Move :Main (if there is one) to the first position.  This is
2859      necessary to get the same layout of the trie-tree when linking as
2860      when objcopying the result as in the objcopy.exp test "simple objcopy
2861      of executable".  It also automatically takes care of assigning serial
2862      number 1 to :Main (as is mandatory).  */
2863   for (i = 0; i < count; i++)
2864     if (table[i] != NULL
2865         && strcmp (table[i]->name, MMIX_START_SYMBOL_NAME) == 0
2866         && (table[i]->flags & (BSF_DEBUGGING|BSF_GLOBAL)) == BSF_GLOBAL)
2867       {
2868         asymbol *mainsym = table[i];
2869         memcpy (table + 1, orig_table, i * sizeof (asymbol *));
2870         table[0] = mainsym;
2871
2872         /* Check that the value assigned to :Main is the same as the entry
2873            address.  The default linker script asserts this.  This is as
2874            good a place as any to check this consistency. */
2875         if ((mainsym->value
2876              + mainsym->section->output_section->vma
2877              + mainsym->section->output_offset)
2878             != bfd_get_start_address (abfd))
2879           {
2880             /* Arbitrary buffer to hold the printable representation of a
2881                vma.  */
2882             char vmas_main[40];
2883             char vmas_start[40];
2884             bfd_vma vma_start = bfd_get_start_address (abfd);
2885
2886             sprintf_vma (vmas_main, mainsym->value);
2887             sprintf_vma (vmas_start, vma_start);
2888
2889             (*_bfd_error_handler)
2890               (_("%s: Bad symbol definition: `Main' set to %s rather"
2891                  " than the start address %s\n"),
2892                bfd_get_filename (abfd), vmas_main, vmas_start);
2893             bfd_set_error (bfd_error_bad_value);
2894             return FALSE;
2895           }
2896         break;
2897       }
2898   if (i == count && count != 0)
2899     {
2900       /* When there are symbols, there must be a :Main.  There was no
2901          :Main, so we need to add it manually.  */
2902       memcpy (table + 1, orig_table, count * sizeof (asymbol *));
2903       table[0] = fakemain;
2904       count++;
2905     }
2906
2907   for (i = 0, serno = 1; i < count && table[i] != NULL; i++)
2908     {
2909       asymbol *s = table[i];
2910
2911       /* It's not enough to consult bfd_is_local_label, since it does not
2912          mean "local" in the sense of linkable-and-observable-after-link.
2913          Let's just check the BSF_GLOBAL flag.
2914
2915          Also, don't export symbols with characters not in the allowed set.  */
2916       if ((s->flags & (BSF_DEBUGGING|BSF_GLOBAL)) == BSF_GLOBAL
2917           && strspn (s->name,
2918                      valid_mmo_symbol_character_set) == strlen (s->name))
2919         {
2920           struct mmo_symbol sym;
2921           memset (&sym, 0, sizeof (sym));
2922
2923           /* Need to strip const here; strdup:ing would leak and the
2924              existing string must be safe to reuse.  */
2925           sym.name = (char *) s->name;
2926           sym.value =
2927             s->value
2928             + s->section->output_section->vma
2929             + s->section->output_offset;
2930
2931           if (bfd_is_und_section (s->section))
2932             sym.sym_type = mmo_undef_sym;
2933           else if (strcmp (s->section->name, MMO_DATA_SECTION_NAME) == 0
2934                    /* The encoding of data symbols require that the "rest"
2935                       of the value fits in 6 bytes, so the upper two bytes
2936                       must be 0x2000.  All other symbols get to be the
2937                       absolute type.  */
2938                    && (sym.value >> 48) == 0x2000)
2939             sym.sym_type = mmo_data_sym;
2940           else if (strcmp (s->section->name, MMIX_REG_SECTION_NAME) == 0)
2941             sym.sym_type = mmo_reg_sym;
2942           else if (strcmp (s->section->name,
2943                            MMIX_REG_CONTENTS_SECTION_NAME) == 0)
2944             {
2945               sym.sym_type = mmo_reg_sym;
2946               sym.value /= 8;
2947             }
2948           else
2949             sym.sym_type = mmo_abs_sym;
2950
2951           /* FIXME: We assume the order of the received symbols is an
2952              ordered mapping of the serial numbers.  This is not
2953              necessarily true if we e.g. objcopy a mmo file to another and
2954              there are gaps in the numbering.  Not sure if this can
2955              happen.  Not sure what to do.  */
2956           sym.serno = serno++;
2957
2958           if (! mmo_internal_add_3_sym (abfd, &root, &sym))
2959             return FALSE;
2960         }
2961     }
2962
2963   /* Change the root node to be a ":"-prefix.  */
2964   root.symchar = ':';
2965   root.middle = root.left;
2966   root.right = NULL;
2967   root.left = NULL;
2968
2969   /* We have to find out if we can fit the whole symbol table in the mmo
2970      symtab.  It would be bad to assume we can always fit it in 262144
2971      bytes.  If we can't, just leave the Main symbol.  */
2972   trie_len = (mmo_internal_3_length (abfd, &root) + 3)/4;
2973
2974   if (trie_len > 0xffff)
2975     {
2976       /* Test this code by using a lower limit in the test above and check
2977          that the single "Main" symbol is emitted and handled properly.
2978          There's no specific test-case.  */
2979       struct mmo_symbol sym;
2980
2981       (*_bfd_error_handler)
2982         (_("%s: warning: symbol table too large for mmo, larger than 65535"
2983            " 32-bit words: %d.  Only `Main' will be emitted.\n"),
2984          bfd_get_filename (abfd), trie_len);
2985
2986       memset (&sym, 0, sizeof (sym));
2987       sym.sym_type = mmo_abs_sym;
2988       sym.name = MMIX_START_SYMBOL_NAME;
2989       sym.serno = 1;
2990       sym.value = bfd_get_start_address (abfd);
2991
2992       /* Then patch up a symbol table to be just the ":Main" symbol.  */
2993       memset (&root, 0, sizeof (root));
2994       root.left = root.middle;
2995       root.symchar = 0xff;
2996       root.middle = NULL;
2997       root.right = NULL;
2998
2999       if (! mmo_internal_add_3_sym (abfd, &root, &sym))
3000         return FALSE;
3001
3002       root.symchar = ':';
3003       root.middle = root.left;
3004       root.right = NULL;
3005       root.left = NULL;
3006
3007       trie_len = (mmo_internal_3_length (abfd, &root) + 3)/4;
3008     }
3009
3010   /* Reset the written-bytes counter.  */
3011   abfd->tdata.mmo_data->byte_no = 0;
3012
3013   /* Put out the lop_stab mark.  */
3014   bfd_put_32 (abfd, (LOP << 24) | (LOP_STAB << 16), buf);
3015   if (bfd_bwrite (buf, 4, abfd) != 4)
3016     return FALSE;
3017
3018   /* Dump out symbols.  */
3019   mmo_internal_3_dump (abfd, &root);
3020
3021   if (trie_len != (abfd->tdata.mmo_data->byte_no + 3)/4)
3022     {
3023       /* I haven't seen this trig.  It seems no use claiming this case
3024          isn't debugged and abort if we get here.  Instead emit a
3025          diagnostic and fail "normally".  */
3026       (*_bfd_error_handler)
3027         (_("%s: internal error, symbol table changed size from %d to %d"
3028            " words\n"),
3029          bfd_get_filename (abfd), trie_len,
3030          (abfd->tdata.mmo_data->byte_no + 3)/4);
3031       bfd_set_error (bfd_error_bad_value);
3032       return FALSE;
3033     }
3034
3035   /* Dump out remaining bytes in the buffer and handle I/O errors by
3036      propagating errors.  */
3037   if ((abfd->tdata.mmo_data->byte_no % 4) != 0
3038       || abfd->tdata.mmo_data->have_error)
3039     {
3040       memset (abfd->tdata.mmo_data->buf + (abfd->tdata.mmo_data->byte_no % 4),
3041               0, 4 - (abfd->tdata.mmo_data->byte_no % 4));
3042
3043       if (abfd->tdata.mmo_data->have_error
3044           || bfd_bwrite (abfd->tdata.mmo_data->buf, 4, abfd) != 4)
3045         return FALSE;
3046     }
3047
3048   bfd_put_32 (abfd, (LOP << 24) | (LOP_END << 16) | trie_len, buf);
3049   return bfd_bwrite (buf, 4, abfd) == 4;
3050 }
3051
3052 /* Write section unless it is the register contents section.  For that, we
3053    instead store the section in the supplied pointer.  This function is
3054    used through bfd_map_over_sections.  */
3055
3056 static void
3057 mmo_write_section_unless_reg_contents (bfd *abfd, asection *sec, void *p)
3058 {
3059   struct mmo_write_sec_info *infop = (struct mmo_write_sec_info *) p;
3060
3061   if (! infop->retval)
3062     return;
3063
3064   if (strcmp (sec->name, MMIX_REG_CONTENTS_SECTION_NAME) == 0)
3065     {
3066       infop->reg_section = sec;
3067       return;
3068     }
3069
3070   /* Exclude the convenience register section.  */
3071   if (strcmp (sec->name, MMIX_REG_SECTION_NAME) == 0)
3072     {
3073       if (bfd_get_section_flags (abfd, sec) & SEC_HAS_CONTENTS)
3074         {
3075           /* Make sure it hasn't got contents.  It seems impossible to
3076              make it carry contents, so we don't have a test-case for
3077              this.  */
3078           (*_bfd_error_handler)
3079             (_("%s: internal error, internal register section %s had"
3080                " contents\n"),
3081              bfd_get_filename (abfd), sec->name);
3082           bfd_set_error (bfd_error_bad_value);
3083           infop->retval = FALSE;
3084           return;
3085         }
3086
3087       return;
3088     }
3089
3090   infop->retval = mmo_internal_write_section (abfd, sec);
3091 }
3092
3093 /* Do the actual output of a file.  Assumes mmo_set_section_contents is
3094    already called. */
3095
3096 static bfd_boolean
3097 mmo_write_object_contents (bfd *abfd)
3098 {
3099   struct mmo_write_sec_info wsecinfo;
3100
3101   /* First, there are a few words of preamble.  */
3102   if (! mmo_internal_write_header (abfd))
3103     return FALSE;
3104
3105   wsecinfo.reg_section = NULL;
3106   wsecinfo.retval = TRUE;
3107
3108   bfd_map_over_sections (abfd, mmo_write_section_unless_reg_contents,
3109                          &wsecinfo);
3110
3111   if (! wsecinfo.retval)
3112     return FALSE;
3113
3114   if (wsecinfo.reg_section != NULL)
3115     {
3116       asection *sec = wsecinfo.reg_section;
3117       unsigned int z = (unsigned int) (sec->vma / 8);
3118
3119       /* Registers 0..31 must not be global.  Do sanity check on the "vma"
3120          of the register contents section and check that it corresponds to
3121          the length of the section.  */
3122       if (z < 32 || z >= 255 || (sec->vma & 7) != 0
3123           || sec->vma != 256 * 8 - sec->size - 8)
3124         {
3125           bfd_set_error (bfd_error_bad_value);
3126
3127           if (sec->size == 0)
3128             /* There must always be at least one such register.  */
3129             (*_bfd_error_handler)
3130               (_("%s: no initialized registers; section length 0\n"),
3131                bfd_get_filename (abfd));
3132           else if (sec->vma > (256 - 32) * 8)
3133             /* Provide better error message for the case of too many
3134                global registers.  */
3135             (*_bfd_error_handler)
3136               (_("%s: too many initialized registers; section length %ld\n"),
3137                bfd_get_filename (abfd),
3138                (long) sec->size);
3139           else
3140             (*_bfd_error_handler)
3141               (_("%s: invalid start address for initialized registers of"
3142                  " length %ld: 0x%lx%08lx\n"),
3143                bfd_get_filename (abfd),
3144                (long) sec->size,
3145                (unsigned long) (sec->vma >> 32), (unsigned long) (sec->vma));
3146
3147           return FALSE;
3148         }
3149
3150       if (! mmo_internal_write_post (abfd, z, sec))
3151         return FALSE;
3152     }
3153   else
3154     if (! mmo_internal_write_post (abfd, 255, NULL))
3155       return FALSE;
3156
3157   return mmo_write_symbols_and_terminator (abfd);
3158 }
3159
3160 /* Return the size of a NULL pointer, so we support linking in an mmo
3161    object.  */
3162
3163 static long
3164 mmo_get_reloc_upper_bound (bfd *abfd ATTRIBUTE_UNUSED,
3165                            asection *sec ATTRIBUTE_UNUSED)
3166 {
3167   return sizeof (void *);
3168 }
3169
3170 /* Similarly canonicalize relocs to empty, filling in the terminating NULL
3171    pointer.  */
3172
3173 long
3174 mmo_canonicalize_reloc (bfd *abfd ATTRIBUTE_UNUSED,
3175                         sec_ptr section ATTRIBUTE_UNUSED, arelent **relptr,
3176                         asymbol **symbols ATTRIBUTE_UNUSED)
3177 {
3178   *relptr = NULL;
3179   return 0;
3180 }
3181
3182 /* If there's anything in particular in a mmo bfd that we want to free,
3183    make this a real function.  Only do this if you see major memory
3184    thrashing; zealous free:ing will cause unwanted behavior, especially if
3185    you "free" memory allocated with "bfd_alloc", or even "bfd_release" a
3186    block allocated with "bfd_alloc"; they're really allocated from an
3187    obstack, and we don't know what was allocated there since this
3188    particular allocation.  */
3189
3190 #define mmo_close_and_cleanup _bfd_generic_close_and_cleanup
3191 #define mmo_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
3192
3193 /* Perhaps we need to adjust this one; mmo labels (originally) without a
3194    leading ':' might more appropriately be called local.  */
3195 #define mmo_bfd_is_local_label_name bfd_generic_is_local_label_name
3196 #define mmo_bfd_is_target_special_symbol  \
3197   ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false)
3198
3199 /* Is this one really used or defined by anyone?  */
3200 #define mmo_get_lineno _bfd_nosymbols_get_lineno
3201
3202 /* FIXME: We can do better on this one, if we have a dwarf2 .debug_line
3203    section or if MMO line numbers are implemented.  */
3204 #define mmo_find_nearest_line _bfd_nosymbols_find_nearest_line
3205 #define mmo_make_empty_symbol _bfd_generic_make_empty_symbol
3206 #define mmo_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
3207 #define mmo_read_minisymbols _bfd_generic_read_minisymbols
3208 #define mmo_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
3209
3210 #define mmo_get_section_contents_in_window \
3211   _bfd_generic_get_section_contents_in_window
3212 #define mmo_bfd_get_relocated_section_contents \
3213   bfd_generic_get_relocated_section_contents
3214 #define mmo_bfd_gc_sections bfd_generic_gc_sections
3215 #define mmo_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
3216 #define mmo_bfd_link_hash_table_free _bfd_generic_link_hash_table_free
3217 #define mmo_bfd_link_add_symbols _bfd_generic_link_add_symbols
3218 #define mmo_bfd_link_just_syms _bfd_generic_link_just_syms
3219 #define mmo_bfd_final_link _bfd_generic_final_link
3220 #define mmo_bfd_link_split_section _bfd_generic_link_split_section
3221
3222 /* Strictly speaking, only MMIX uses this restricted format, but let's not
3223    stop anybody from shooting themselves in the foot.  */
3224 #define mmo_set_arch_mach bfd_default_set_arch_mach
3225 #define mmo_bfd_relax_section bfd_generic_relax_section
3226 #define mmo_bfd_merge_sections bfd_generic_merge_sections
3227 #define mmo_bfd_is_group_section bfd_generic_is_group_section
3228 #define mmo_bfd_discard_group bfd_generic_discard_group
3229 #define mmo_section_already_linked \
3230   _bfd_generic_section_already_linked
3231
3232 /* objcopy will be upset if we return -1 from bfd_get_reloc_upper_bound by
3233    using BFD_JUMP_TABLE_RELOCS (_bfd_norelocs) rather than 0.  FIXME: Most
3234    likely a bug in the _bfd_norelocs definition.
3235
3236    On the other hand, we smuggle in an mmo object (because setting up ELF
3237    is too cumbersome) when linking (from other formats, presumably ELF) to
3238    represent the g255 entry.  We need to link that object, so need to say
3239    it has no relocs.  Upper bound for the size of the relocation table is
3240    the size of a NULL pointer, and we support "canonicalization" for that
3241    pointer.  */
3242 #define mmo_bfd_reloc_type_lookup _bfd_norelocs_bfd_reloc_type_lookup
3243
3244 /* We want to copy time of creation, otherwise we'd use
3245    BFD_JUMP_TABLE_COPY (_bfd_generic).  */
3246 #define mmo_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data
3247 #define mmo_bfd_copy_private_section_data _bfd_generic_bfd_copy_private_section_data
3248 #define mmo_bfd_copy_private_symbol_data _bfd_generic_bfd_copy_private_symbol_data
3249 #define mmo_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data
3250 #define mmo_bfd_set_private_flags _bfd_generic_bfd_set_private_flags
3251 #define mmo_bfd_print_private_bfd_data _bfd_generic_bfd_print_private_bfd_data
3252
3253 const bfd_target bfd_mmo_vec =
3254 {
3255   "mmo",                        /* name */
3256   bfd_target_mmo_flavour,
3257   BFD_ENDIAN_BIG,               /* target byte order */
3258   BFD_ENDIAN_BIG,               /* target headers byte order */
3259
3260   /* FIXME: Might need adjustments.  */
3261   (HAS_RELOC | EXEC_P |         /* object flags */
3262    HAS_LINENO | HAS_DEBUG |
3263    HAS_SYMS | HAS_LOCALS | WP_TEXT),
3264
3265   /* FIXME: Might need adjustments.  */
3266   (SEC_CODE | SEC_DATA | SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD
3267    | SEC_READONLY | SEC_EXCLUDE | SEC_DEBUGGING | SEC_IN_MEMORY),
3268                                 /* section flags */
3269   0,                            /* leading underscore */
3270   ' ',                          /* ar_pad_char */
3271   16,                           /* ar_max_namelen */
3272   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
3273   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
3274   bfd_getb16, bfd_getb_signed_16, bfd_putb16,   /* data */
3275   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
3276   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
3277   bfd_getb16, bfd_getb_signed_16, bfd_putb16,   /* hdrs */
3278
3279   {
3280     _bfd_dummy_target,
3281     mmo_object_p,               /* bfd_check_format */
3282     _bfd_dummy_target,
3283     _bfd_dummy_target,
3284   },
3285   {
3286     bfd_false,
3287     mmo_mkobject,
3288     bfd_false,
3289     bfd_false,
3290   },
3291   {                             /* bfd_write_contents */
3292     bfd_false,
3293     mmo_write_object_contents,
3294     bfd_false,
3295     bfd_false,
3296   },
3297
3298   BFD_JUMP_TABLE_GENERIC (mmo),
3299   BFD_JUMP_TABLE_COPY (mmo),
3300   BFD_JUMP_TABLE_CORE (_bfd_nocore),
3301   BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
3302   BFD_JUMP_TABLE_SYMBOLS (mmo),
3303   /* We have to provide a valid method for getting relocs, returning zero,
3304      so we can't say BFD_JUMP_TABLE_RELOCS (_bfd_norelocs).  */
3305   BFD_JUMP_TABLE_RELOCS (mmo),
3306   BFD_JUMP_TABLE_WRITE (mmo),
3307   BFD_JUMP_TABLE_LINK (mmo),
3308   BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
3309
3310   NULL,
3311
3312   NULL
3313 };