gas/config/obj-aout.c

   1 /* a.out object file format
   2    Copyright (C) 1989, 1990, 1991 Free Software Foundation, Inc.
   3
   4 This file is part of GAS, the GNU Assembler.
   5
   6 GAS is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as
   8 published by the Free Software Foundation; either version 2,
   9 or (at your option) any later version.
  10
  11 GAS is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  14 the GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public
  17 License along with GAS; see the file COPYING.  If not, write
  18 to the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
  19
  20 #include "as.h"
  21 #ifdef BFD_ASSEMBLER
  22 #undef NO_RELOC
  23 #include "aout/aout64.h"
  24 #endif
  25 #include "obstack.h"
  26
  27 #ifndef BFD_ASSEMBLER
  28 /* in: segT   out: N_TYPE bits */
  29 const short seg_N_TYPE[] =
  30 {
  31   N_ABS,
  32   N_TEXT,
  33   N_DATA,
  34   N_BSS,
  35   N_UNDF,                       /* unknown */
  36   N_UNDF,                       /* error */
  37   N_UNDF,                       /* expression */
  38   N_UNDF,                       /* debug */
  39   N_UNDF,                       /* ntv */
  40   N_UNDF,                       /* ptv */
  41   N_REGISTER,                   /* register */
  42 };
  43
  44 const segT N_TYPE_seg[N_TYPE + 2] =
  45 {                               /* N_TYPE == 0x1E = 32-2 */
  46   SEG_UNKNOWN,                  /* N_UNDF == 0 */
  47   SEG_GOOF,
  48   SEG_ABSOLUTE,                 /* N_ABS == 2 */
  49   SEG_GOOF,
  50   SEG_TEXT,                     /* N_TEXT == 4 */
  51   SEG_GOOF,
  52   SEG_DATA,                     /* N_DATA == 6 */
  53   SEG_GOOF,
  54   SEG_BSS,                      /* N_BSS == 8 */
  55   SEG_GOOF,
  56   SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  57   SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  58   SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  59   SEG_REGISTER,                 /* dummy N_REGISTER for regs = 30 */
  60   SEG_GOOF,
  61 };
  62 #endif
  63
  64 static void obj_aout_line PARAMS ((int));
  65 static void obj_aout_weak PARAMS ((int));
  66
  67 const pseudo_typeS obj_pseudo_table[] =
  68 {
  69   {"line", obj_aout_line, 0},   /* source code line number */
  70   {"ln", obj_aout_line, 0},     /* coff line number that we use anyway */
  71
  72   {"weak", obj_aout_weak, 0},   /* mark symbol as weak.  */
  73
  74   /* coff debug pseudos (ignored) */
  75   {"def", s_ignore, 0},
  76   {"dim", s_ignore, 0},
  77   {"endef", s_ignore, 0},
  78   {"ident", s_ignore, 0},
  79   {"line", s_ignore, 0},
  80   {"ln", s_ignore, 0},
  81   {"scl", s_ignore, 0},
  82   {"size", s_ignore, 0},
  83   {"tag", s_ignore, 0},
  84   {"type", s_ignore, 0},
  85   {"val", s_ignore, 0},
  86   {"version", s_ignore, 0},
  87
  88   {"optim", s_ignore, 0},       /* For sun386i cc (?) */
  89
  90   /* other stuff */
  91   {"ABORT", s_abort, 0},
  92
  93   {NULL}                        /* end sentinel */
  94 };                              /* obj_pseudo_table */
  95
  96
  97 #ifdef BFD_ASSEMBLER
  98
  99 void
 100 obj_aout_frob_symbol (sym, punt)
 101      symbolS *sym;
 102      int *punt;
 103 {
 104   flagword flags;
 105   asection *sec;
 106   int desc, type, other;
 107
 108   flags = sym->bsym->flags;
 109   desc = S_GET_DESC (sym);
 110   type = S_GET_TYPE (sym);
 111   other = S_GET_OTHER (sym);
 112   sec = sym->bsym->section;
 113
 114   /* Only frob simple symbols this way right now.  */
 115   if (! (type & ~ (N_TYPE | N_EXT)))
 116     {
 117       if (type == (N_UNDF | N_EXT)
 118           && sec == &bfd_abs_section)
 119         sym->bsym->section = sec = &bfd_und_section;
 120
 121       if ((type & N_TYPE) != N_INDR
 122           && (type & N_TYPE) != N_SETA
 123           && (type & N_TYPE) != N_SETT
 124           && (type & N_TYPE) != N_SETD
 125           && (type & N_TYPE) != N_SETB
 126           && type != N_WARNING
 127           && (sec == &bfd_abs_section
 128               || sec == &bfd_und_section))
 129         return;
 130       if (flags & BSF_EXPORT)
 131         type |= N_EXT;
 132
 133       switch (type & N_TYPE)
 134         {
 135         case N_SETA:
 136         case N_SETT:
 137         case N_SETD:
 138         case N_SETB:
 139           /* Set the debugging flag for constructor symbols so that
 140              BFD leaves them alone.  */
 141           sym->bsym->flags |= BSF_DEBUGGING;
 142           break;
 143         case N_INDR:
 144           /* Put indirect symbols in the indirect section.  */
 145           sym->bsym->section = &bfd_ind_section;
 146           sym->bsym->flags |= BSF_INDIRECT;
 147           if (type & N_EXT)
 148             {
 149               sym->bsym->flags |= BSF_EXPORT;
 150               sym->bsym->flags &=~ BSF_LOCAL;
 151             }
 152           break;
 153         case N_WARNING:
 154           /* Mark warning symbols.  */
 155           sym->bsym->flags |= BSF_WARNING;
 156           break;
 157         }
 158     }
 159   else
 160     {
 161       sym->bsym->flags |= BSF_DEBUGGING;
 162     }
 163
 164   S_SET_TYPE (sym, type);
 165 }
 166
 167 void
 168 obj_aout_frob_file ()
 169 {
 170   /* Relocation processing may require knowing the VMAs of the sections.
 171      Since writing to a section will cause the BFD back end to compute the
 172      VMAs, fake it out here....  */
 173   bfd_byte b = 0;
 174   boolean x = true;
 175   if (bfd_section_size (stdoutput, text_section) != 0)
 176     {
 177       x = bfd_set_section_contents (stdoutput, text_section, &b, (file_ptr) 0,
 178                                     (bfd_size_type) 1);
 179     }
 180   else if (bfd_section_size (stdoutput, data_section) != 0)
 181     {
 182       x = bfd_set_section_contents (stdoutput, data_section, &b, (file_ptr) 0,
 183                                     (bfd_size_type) 1);
 184     }
 185   assert (x == true);
 186 }
 187
 188 #else
 189
 190 /* Relocation. */
 191
 192 /*
 193  *              emit_relocations()
 194  *
 195  * Crawl along a fixS chain. Emit the segment's relocations.
 196  */
 197 void
 198 obj_emit_relocations (where, fixP, segment_address_in_file)
 199      char **where;
 200      fixS *fixP;                /* Fixup chain for this segment. */
 201      relax_addressT segment_address_in_file;
 202 {
 203   for (; fixP; fixP = fixP->fx_next)
 204     if (fixP->fx_done == 0)
 205       {
 206         tc_aout_fix_to_chars (*where, fixP, segment_address_in_file);
 207         *where += md_reloc_size;
 208       }
 209 }
 210
 211 #ifndef obj_header_append
 212 /* Aout file generation & utilities */
 213 void
 214 obj_header_append (where, headers)
 215      char **where;
 216      object_headers *headers;
 217 {
 218   tc_headers_hook (headers);
 219
 220 #ifdef CROSS_COMPILE
 221   md_number_to_chars (*where, headers->header.a_info, sizeof (headers->header.a_info));
 222   *where += sizeof (headers->header.a_info);
 223   md_number_to_chars (*where, headers->header.a_text, sizeof (headers->header.a_text));
 224   *where += sizeof (headers->header.a_text);
 225   md_number_to_chars (*where, headers->header.a_data, sizeof (headers->header.a_data));
 226   *where += sizeof (headers->header.a_data);
 227   md_number_to_chars (*where, headers->header.a_bss, sizeof (headers->header.a_bss));
 228   *where += sizeof (headers->header.a_bss);
 229   md_number_to_chars (*where, headers->header.a_syms, sizeof (headers->header.a_syms));
 230   *where += sizeof (headers->header.a_syms);
 231   md_number_to_chars (*where, headers->header.a_entry, sizeof (headers->header.a_entry));
 232   *where += sizeof (headers->header.a_entry);
 233   md_number_to_chars (*where, headers->header.a_trsize, sizeof (headers->header.a_trsize));
 234   *where += sizeof (headers->header.a_trsize);
 235   md_number_to_chars (*where, headers->header.a_drsize, sizeof (headers->header.a_drsize));
 236   *where += sizeof (headers->header.a_drsize);
 237
 238 #else /* CROSS_COMPILE */
 239
 240   append (where, (char *) &headers->header, sizeof (headers->header));
 241 #endif /* CROSS_COMPILE */
 242
 243 }
 244 #endif
 245
 246 void
 247 obj_symbol_to_chars (where, symbolP)
 248      char **where;
 249      symbolS *symbolP;
 250 {
 251   md_number_to_chars ((char *) &(S_GET_OFFSET (symbolP)), S_GET_OFFSET (symbolP), sizeof (S_GET_OFFSET (symbolP)));
 252   md_number_to_chars ((char *) &(S_GET_DESC (symbolP)), S_GET_DESC (symbolP), sizeof (S_GET_DESC (symbolP)));
 253   md_number_to_chars ((char *) &(symbolP->sy_symbol.n_value), S_GET_VALUE (symbolP), sizeof (symbolP->sy_symbol.n_value));
 254
 255   append (where, (char *) &symbolP->sy_symbol, sizeof (obj_symbol_type));
 256 }
 257
 258 void
 259 obj_emit_symbols (where, symbol_rootP)
 260      char **where;
 261      symbolS *symbol_rootP;
 262 {
 263   symbolS *symbolP;
 264
 265   /* Emit all symbols left in the symbol chain.  */
 266   for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
 267     {
 268       /* Used to save the offset of the name. It is used to point
 269          to the string in memory but must be a file offset. */
 270       register char *temp;
 271
 272       temp = S_GET_NAME (symbolP);
 273       S_SET_OFFSET (symbolP, symbolP->sy_name_offset);
 274
 275       /* Any symbol still undefined and is not a dbg symbol is made N_EXT. */
 276       if (!S_IS_DEBUG (symbolP) && !S_IS_DEFINED (symbolP))
 277         S_SET_EXTERNAL (symbolP);
 278
 279       /* Adjust the type of a weak symbol.  */
 280       if (S_GET_WEAK (symbolP))
 281         {
 282           switch (S_GET_TYPE (symbolP))
 283             {
 284             case N_UNDF: S_SET_TYPE (symbolP, N_WEAKU); break;
 285             case N_ABS:  S_SET_TYPE (symbolP, N_WEAKA); break;
 286             case N_TEXT: S_SET_TYPE (symbolP, N_WEAKT); break;
 287             case N_DATA: S_SET_TYPE (symbolP, N_WEAKD); break;
 288             case N_BSS:  S_SET_TYPE (symbolP, N_WEAKB); break;
 289             default: as_bad ("%s: bad type for weak symbol", temp); break;
 290             }
 291         }
 292
 293       obj_symbol_to_chars (where, symbolP);
 294       S_SET_NAME (symbolP, temp);
 295     }
 296 }
 297
 298 #endif /* ! BFD_ASSEMBLER */
 299
 300 static void
 301 obj_aout_line (ignore)
 302      int ignore;
 303 {
 304   /* Assume delimiter is part of expression.
 305      BSD4.2 as fails with delightful bug, so we
 306      are not being incompatible here. */
 307   new_logical_line ((char *) NULL, (int) (get_absolute_expression ()));
 308   demand_empty_rest_of_line ();
 309 }                               /* obj_aout_line() */
 310
 311 /* Handle .weak.  This is a GNU extension.  */
 312
 313 static void
 314 obj_aout_weak (ignore)
 315      int ignore;
 316 {
 317   char *name;
 318   int c;
 319   symbolS *symbolP;
 320
 321   do
 322     {
 323       name = input_line_pointer;
 324       c = get_symbol_end ();
 325       symbolP = symbol_find_or_make (name);
 326       *input_line_pointer = c;
 327       SKIP_WHITESPACE ();
 328       S_SET_WEAK (symbolP);
 329       if (c == ',')
 330         {
 331           input_line_pointer++;
 332           SKIP_WHITESPACE ();
 333           if (*input_line_pointer == '\n')
 334             c = '\n';
 335         }
 336     }
 337   while (c == ',');
 338   demand_empty_rest_of_line ();
 339 }
 340
 341 void
 342 obj_read_begin_hook ()
 343 {
 344 }
 345
 346 #ifndef BFD_ASSEMBLER
 347
 348 void
 349 obj_crawl_symbol_chain (headers)
 350      object_headers *headers;
 351 {
 352   symbolS *symbolP;
 353   symbolS **symbolPP;
 354   int symbol_number = 0;
 355
 356   tc_crawl_symbol_chain (headers);
 357
 358   symbolPP = &symbol_rootP;     /*->last symbol chain link. */
 359   while ((symbolP = *symbolPP) != NULL)
 360     {
 361       if (flag_readonly_data_in_text && (S_GET_SEGMENT (symbolP) == SEG_DATA))
 362         {
 363           S_SET_SEGMENT (symbolP, SEG_TEXT);
 364         }                       /* if pusing data into text */
 365
 366       resolve_symbol_value (symbolP);
 367
 368       /* OK, here is how we decide which symbols go out into the brave
 369          new symtab.  Symbols that do are:
 370
 371          * symbols with no name (stabd's?)
 372          * symbols with debug info in their N_TYPE
 373
 374          Symbols that don't are:
 375          * symbols that are registers
 376          * symbols with \1 as their 3rd character (numeric labels)
 377          * "local labels" as defined by S_LOCAL_NAME(name) if the -L
 378          switch was passed to gas.
 379
 380          All other symbols are output.  We complain if a deleted
 381          symbol was marked external. */
 382
 383
 384       if (!S_IS_REGISTER (symbolP)
 385           && (!S_GET_NAME (symbolP)
 386               || S_IS_DEBUG (symbolP)
 387               || !S_IS_DEFINED (symbolP)
 388               || S_IS_EXTERNAL (symbolP)
 389               || (S_GET_NAME (symbolP)[0] != '\001'
 390                   && (flag_keep_locals || !S_LOCAL_NAME (symbolP)))))
 391         {
 392           symbolP->sy_number = symbol_number++;
 393
 394           /* The + 1 after strlen account for the \0 at the
 395                            end of each string */
 396           if (!S_IS_STABD (symbolP))
 397             {
 398               /* Ordinary case. */
 399               symbolP->sy_name_offset = string_byte_count;
 400               string_byte_count += strlen (S_GET_NAME (symbolP)) + 1;
 401             }
 402           else                  /* .Stabd case. */
 403             symbolP->sy_name_offset = 0;
 404           symbolPP = &(symbol_next (symbolP));
 405         }
 406       else
 407         {
 408           if (S_IS_EXTERNAL (symbolP) || !S_IS_DEFINED (symbolP))
 409             /* This warning should never get triggered any more.
 410                Well, maybe if you're doing twisted things with
 411                register names...  */
 412             {
 413               as_bad ("Local symbol %s never defined.", decode_local_label_name (S_GET_NAME (symbolP)));
 414             }                   /* oops. */
 415
 416           /* Unhook it from the chain */
 417           *symbolPP = symbol_next (symbolP);
 418         }                       /* if this symbol should be in the output */
 419     }                           /* for each symbol */
 420
 421   H_SET_SYMBOL_TABLE_SIZE (headers, symbol_number);
 422 }
 423
 424 /*
 425  * Find strings by crawling along symbol table chain.
 426  */
 427
 428 void
 429 obj_emit_strings (where)
 430      char **where;
 431 {
 432   symbolS *symbolP;
 433
 434 #ifdef CROSS_COMPILE
 435   /* Gotta do md_ byte-ordering stuff for string_byte_count first - KWK */
 436   md_number_to_chars (*where, string_byte_count, sizeof (string_byte_count));
 437   *where += sizeof (string_byte_count);
 438 #else /* CROSS_COMPILE */
 439   append (where, (char *) &string_byte_count, (unsigned long) sizeof (string_byte_count));
 440 #endif /* CROSS_COMPILE */
 441
 442   for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
 443     {
 444       if (S_GET_NAME (symbolP))
 445         append (&next_object_file_charP, S_GET_NAME (symbolP),
 446                 (unsigned long) (strlen (S_GET_NAME (symbolP)) + 1));
 447     }                           /* walk symbol chain */
 448 }
 449
 450 #ifndef AOUT_VERSION
 451 #define AOUT_VERSION 0
 452 #endif
 453
 454 void
 455 obj_pre_write_hook (headers)
 456      object_headers *headers;
 457 {
 458   H_SET_DYNAMIC (headers, 0);
 459   H_SET_VERSION (headers, AOUT_VERSION);
 460   H_SET_MACHTYPE (headers, AOUT_MACHTYPE);
 461   tc_aout_pre_write_hook (headers);
 462 }
 463
 464 void
 465 DEFUN_VOID (s_sect)
 466 {
 467   /* Strip out the section name */
 468   char *section_name;
 469   char *section_name_end;
 470   char c;
 471
 472   unsigned int len;
 473   unsigned int exp;
 474   char *save;
 475
 476   section_name = input_line_pointer;
 477   c = get_symbol_end ();
 478   section_name_end = input_line_pointer;
 479
 480   len = section_name_end - section_name;
 481   input_line_pointer++;
 482   save = input_line_pointer;
 483
 484   SKIP_WHITESPACE ();
 485   if (c == ',')
 486     {
 487       exp = get_absolute_expression ();
 488     }
 489   else if (*input_line_pointer == ',')
 490     {
 491       input_line_pointer++;
 492       exp = get_absolute_expression ();
 493     }
 494   else
 495     {
 496       input_line_pointer = save;
 497       exp = 0;
 498     }
 499   if (exp >= 1000)
 500     {
 501       as_bad ("subsegment index too high");
 502     }
 503
 504   if (strcmp (section_name, ".text") == 0)
 505     {
 506       subseg_set (SEG_TEXT, (subsegT) exp);
 507     }
 508
 509   if (strcmp (section_name, ".data") == 0)
 510     {
 511       if (flag_readonly_data_in_text)
 512         subseg_set (SEG_TEXT, (subsegT) exp + 1000);
 513       else
 514         subseg_set (SEG_DATA, (subsegT) exp);
 515     }
 516
 517   *section_name_end = c;
 518 }
 519
 520 #endif /* ! BFD_ASSEMBLER */
 521
 522 /* end of obj-aout.c */