bfd/libecoff.h

   1 /* BFD ECOFF object file private structure.
   2    Copyright 1993, 1994, 1995, 1996, 1999, 2001, 2002
   3    Free Software Foundation, Inc.
   4    Written by Ian Lance Taylor, Cygnus Support.
   5
   6 This file is part of BFD, the Binary File Descriptor library.
   7
   8 This program is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2 of the License, or
  11 (at your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #include "bfdlink.h"
  23
  24 #ifndef ECOFF_H
  25 #include "coff/ecoff.h"
  26 #endif
  27
  28 /* This is the backend information kept for ECOFF files.  This
  29    structure is constant for a particular backend.  The first element
  30    is the COFF backend data structure, so that ECOFF targets can use
  31    the generic COFF code.  */
  32
  33 #define ecoff_backend(abfd) \
  34   ((struct ecoff_backend_data *) (abfd)->xvec->backend_data)
  35
  36 struct ecoff_backend_data
  37 {
  38   /* COFF backend information.  This must be the first field.  */
  39   bfd_coff_backend_data coff;
  40   /* Supported architecture.  */
  41   enum bfd_architecture arch;
  42   /* Initial portion of armap string.  */
  43   const char *armap_start;
  44   /* The page boundary used to align sections in a demand-paged
  45      executable file.  E.g., 0x1000.  */
  46   bfd_vma round;
  47   /* True if the .rdata section is part of the text segment, as on the
  48      Alpha.  False if .rdata is part of the data segment, as on the
  49      MIPS.  */
  50   boolean rdata_in_text;
  51   /* Bitsize of constructor entries.  */
  52   unsigned int constructor_bitsize;
  53   /* Reloc to use for constructor entries.  */
  54   reloc_howto_type *constructor_reloc;
  55   /* How to swap debugging information.  */
  56   struct ecoff_debug_swap debug_swap;
  57   /* External reloc size.  */
  58   bfd_size_type external_reloc_size;
  59   /* Reloc swapping functions.  */
  60   void (*swap_reloc_in) PARAMS ((bfd *, PTR, struct internal_reloc *));
  61   void (*swap_reloc_out) PARAMS ((bfd *, const struct internal_reloc *, PTR));
  62   /* Backend reloc tweaking.  */
  63   void (*adjust_reloc_in) PARAMS ((bfd *, const struct internal_reloc *,
  64                                    arelent *));
  65   void (*adjust_reloc_out) PARAMS ((bfd *, const arelent *,
  66                                     struct internal_reloc *));
  67   /* Relocate section contents while linking.  */
  68   boolean (*relocate_section) PARAMS ((bfd *output_bfd, struct bfd_link_info *,
  69                                        bfd *input_bfd, asection *input_section,
  70                                        bfd_byte *contents,
  71                                        PTR external_relocs));
  72   /* Do final adjustments to filehdr and aouthdr.  */
  73   boolean (*adjust_headers) PARAMS ((bfd *, struct internal_filehdr *,
  74                                      struct internal_aouthdr *));
  75   /* Read an element from an archive at a given file position.  This
  76      is needed because OSF/1 3.2 uses a weird archive format.  */
  77   bfd *(*get_elt_at_filepos) PARAMS ((bfd *, file_ptr));
  78 };
  79
  80 /* This is the target specific information kept for ECOFF files.  */
  81
  82 #define ecoff_data(abfd) ((abfd)->tdata.ecoff_obj_data)
  83
  84 typedef struct ecoff_tdata
  85 {
  86   /* The reloc file position, set by
  87      ecoff_compute_section_file_positions.  */
  88   file_ptr reloc_filepos;
  89
  90   /* The symbol table file position, set by _bfd_ecoff_mkobject_hook.  */
  91   file_ptr sym_filepos;
  92
  93   /* The start and end of the text segment.  Only valid for an
  94      existing file, not for one we are creating.  */
  95   unsigned long text_start;
  96   unsigned long text_end;
  97
  98   /* The cached gp value.  This is used when relocating.  */
  99   bfd_vma gp;
 100
 101   /* The maximum size of objects to optimize using gp.  This is
 102      typically set by the -G option to the compiler, assembler or
 103      linker.  */
 104   unsigned int gp_size;
 105
 106   /* The register masks.  When linking, all the masks found in the
 107      input files are combined into the masks of the output file.
 108      These are not all used for all targets, but that's OK, because
 109      the relevant ones are the only ones swapped in and out.  */
 110   unsigned long gprmask;
 111   unsigned long fprmask;
 112   unsigned long cprmask[4];
 113
 114   /* The ECOFF symbolic debugging information.  */
 115   struct ecoff_debug_info debug_info;
 116
 117   /* The unswapped ECOFF symbolic information.  */
 118   PTR raw_syments;
 119
 120   /* The canonical BFD symbols.  */
 121   struct ecoff_symbol_struct *canonical_symbols;
 122
 123   /* A mapping from external symbol numbers to entries in the linker
 124      hash table, used when linking.  */
 125   struct ecoff_link_hash_entry **sym_hashes;
 126
 127   /* A mapping from reloc symbol indices to sections, used when
 128      linking.  */
 129   asection **symndx_to_section;
 130
 131   /* True if this BFD was written by the backend linker.  */
 132   boolean linker;
 133
 134   /* True if a warning that multiple global pointer values are
 135      needed in the output binary was issued already.  */
 136   boolean issued_multiple_gp_warning;
 137
 138   /* Used by find_nearest_line entry point.  The structure could be
 139      included directly in this one, but there's no point to wasting
 140      the memory just for the infrequently called find_nearest_line.  */
 141   struct ecoff_find_line *find_line_info;
 142
 143   /* Whether the .rdata section is in the text segment for this
 144      particular ECOFF file.  This is not valid until
 145      ecoff_compute_section_file_positions is called.  */
 146   boolean rdata_in_text;
 147
 148 } ecoff_data_type;
 149
 150 /* Each canonical asymbol really looks like this.  */
 151
 152 typedef struct ecoff_symbol_struct
 153 {
 154   /* The actual symbol which the rest of BFD works with */
 155   asymbol symbol;
 156
 157   /* The fdr for this symbol.  */
 158   FDR *fdr;
 159
 160   /* true if this is a local symbol rather than an external one.  */
 161   boolean local;
 162
 163   /* A pointer to the unswapped hidden information for this symbol.
 164      This is either a struct sym_ext or a struct ext_ext, depending on
 165      the value of the local field above.  */
 166   PTR native;
 167 } ecoff_symbol_type;
 168
 169 /* We take the address of the first element of an asymbol to ensure that the
 170    macro is only ever applied to an asymbol.  */
 171 #define ecoffsymbol(asymbol) ((ecoff_symbol_type *) (&((asymbol)->the_bfd)))
 172
 173 /* We need to save the index of an external symbol when we write it
 174    out so that can set the symbol index correctly when we write out
 175    the relocs.  */
 176 #define ecoff_get_sym_index(symbol) ((symbol)->udata.i)
 177 #define ecoff_set_sym_index(symbol, idx) ((symbol)->udata.i = (idx))
 178
 179 /* When generating MIPS embedded PIC code, the linker relaxes the code
 180    to turn PC relative branches into longer code sequences when the PC
 181    relative branch is out of range.  This involves reading the relocs
 182    in bfd_relax_section as well as in bfd_final_link, and requires the
 183    code to keep track of which relocs have been expanded.  A pointer
 184    to this structure is put in the used_by_bfd pointer of a section to
 185    keep track of this information.  The user_by_bfd pointer will be
 186    NULL if the information was not needed.  */
 187
 188 struct ecoff_section_tdata
 189 {
 190   /* The unswapped relocs for this section.  These are stored in
 191      memory so the input file does not have to be read twice.  */
 192   PTR external_relocs;
 193
 194   /* The contents of the section.  These bytes may or may not be saved
 195      in memory, but if it is this is a pointer to them.  */
 196   bfd_byte *contents;
 197
 198   /* Offset adjustments for PC relative branches.  A number other than
 199      1 is an addend for a PC relative branch, or a switch table entry
 200      which is the difference of two .text locations; this addend
 201      arises because the branch or difference crosses one or more
 202      branches which were expanded into a larger code sequence.  A 1
 203      means that this branch was itself expanded into a larger code
 204      sequence.  1 is not a possible offset, since all offsets must be
 205      multiples of the instruction size, which is 4; also, the only
 206      relocs with non-zero offsets will be PC relative branches or
 207      switch table entries within the same object file.  If this field
 208      is NULL, no branches were expanded and no offsets are required.
 209      Otherwise there are as many entries as there are relocs in the
 210      section, and the entry for any reloc that is not PC relative is
 211      zero.  */
 212   long *offsets;
 213
 214   /* When producing an executable (i.e., final, non-relocatable link)
 215      on the Alpha, we may need to use multiple global pointer values
 216      to span the entire .lita section.  In essence, we allow each
 217      input .lita section to have its own gp value.  To support this,
 218      we need to keep track of the gp values that we picked for each
 219      input .lita section . */
 220   bfd_vma gp;
 221 };
 222
 223 /* An accessor macro for the ecoff_section_tdata structure.  */
 224 #define ecoff_section_data(abfd, sec) \
 225   ((struct ecoff_section_tdata *) (sec)->used_by_bfd)
 226
 227 /* ECOFF linker hash table entries.  */
 228
 229 struct ecoff_link_hash_entry
 230 {
 231   struct bfd_link_hash_entry root;
 232   /* Symbol index in output file.  */
 233   long indx;
 234   /* BFD that ext field value came from.  */
 235   bfd *abfd;
 236   /* ECOFF external symbol information.  */
 237   EXTR esym;
 238   /* Nonzero if this symbol has been written out.  */
 239   char written;
 240   /* Nonzero if this symbol was referred to as small undefined.  */
 241   char small;
 242 };
 243
 244 /* ECOFF linker hash table.  */
 245
 246 struct ecoff_link_hash_table
 247 {
 248   struct bfd_link_hash_table root;
 249 };
 250
 251 /* Make an ECOFF object.  */
 252 extern boolean _bfd_ecoff_mkobject PARAMS ((bfd *));
 253
 254 /* Read in the ECOFF symbolic debugging information.  */
 255 extern boolean _bfd_ecoff_slurp_symbolic_info
 256   PARAMS ((bfd *, asection *, struct ecoff_debug_info *));
 257
 258 /* Generic ECOFF BFD backend vectors.  */
 259
 260 extern boolean _bfd_ecoff_write_object_contents PARAMS ((bfd *abfd));
 261 extern const bfd_target *_bfd_ecoff_archive_p PARAMS ((bfd *abfd));
 262
 263 #define _bfd_ecoff_close_and_cleanup _bfd_generic_close_and_cleanup
 264 #define _bfd_ecoff_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
 265 extern boolean _bfd_ecoff_new_section_hook
 266   PARAMS ((bfd *, asection *));
 267 extern boolean _bfd_ecoff_get_section_contents
 268   PARAMS ((bfd *, asection *, PTR location, file_ptr, bfd_size_type));
 269
 270 #define _bfd_ecoff_bfd_link_split_section _bfd_generic_link_split_section
 271
 272 extern boolean _bfd_ecoff_bfd_copy_private_bfd_data PARAMS ((bfd *, bfd *));
 273 #define _bfd_ecoff_bfd_copy_private_section_data \
 274   _bfd_generic_bfd_copy_private_section_data
 275
 276 #define _bfd_ecoff_bfd_copy_private_symbol_data \
 277   _bfd_generic_bfd_copy_private_symbol_data
 278
 279 #define _bfd_ecoff_bfd_print_private_bfd_data \
 280   _bfd_generic_bfd_print_private_bfd_data
 281
 282 #define _bfd_ecoff_bfd_merge_private_bfd_data \
 283   _bfd_generic_bfd_merge_private_bfd_data
 284
 285 #define _bfd_ecoff_bfd_set_private_flags _bfd_generic_bfd_set_private_flags
 286 extern boolean _bfd_ecoff_slurp_armap PARAMS ((bfd *abfd));
 287 #define _bfd_ecoff_slurp_extended_name_table _bfd_slurp_extended_name_table
 288 #define _bfd_ecoff_construct_extended_name_table \
 289   _bfd_archive_bsd_construct_extended_name_table
 290 #define _bfd_ecoff_truncate_arname bfd_dont_truncate_arname
 291 extern boolean _bfd_ecoff_write_armap
 292   PARAMS ((bfd *, unsigned int, struct orl *, unsigned int, int));
 293 #define _bfd_ecoff_read_ar_hdr _bfd_generic_read_ar_hdr
 294 #define _bfd_ecoff_openr_next_archived_file \
 295   bfd_generic_openr_next_archived_file
 296 #define _bfd_ecoff_get_elt_at_index _bfd_generic_get_elt_at_index
 297 #define _bfd_ecoff_generic_stat_arch_elt bfd_generic_stat_arch_elt
 298 #define _bfd_ecoff_update_armap_timestamp bfd_true
 299
 300 extern long _bfd_ecoff_get_symtab_upper_bound PARAMS ((bfd *abfd));
 301 extern long _bfd_ecoff_get_symtab PARAMS ((bfd *abfd, asymbol **alocation));
 302 extern asymbol *_bfd_ecoff_make_empty_symbol PARAMS ((bfd *abfd));
 303 extern void _bfd_ecoff_print_symbol
 304   PARAMS ((bfd *, PTR filep, asymbol *, bfd_print_symbol_type));
 305 extern void _bfd_ecoff_get_symbol_info
 306   PARAMS ((bfd *, asymbol *, symbol_info *));
 307 extern boolean _bfd_ecoff_bfd_is_local_label_name
 308   PARAMS ((bfd *, const char *));
 309 #define _bfd_ecoff_get_lineno _bfd_nosymbols_get_lineno
 310 extern boolean _bfd_ecoff_find_nearest_line
 311   PARAMS ((bfd *, asection *, asymbol **, bfd_vma offset,
 312            const char **filename_ptr, const char **fnname_ptr,
 313            unsigned int *retline_ptr));
 314 #define _bfd_ecoff_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
 315 #define _bfd_ecoff_read_minisymbols _bfd_generic_read_minisymbols
 316 #define _bfd_ecoff_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
 317
 318 #define _bfd_ecoff_get_reloc_upper_bound coff_get_reloc_upper_bound
 319 extern long _bfd_ecoff_canonicalize_reloc
 320   PARAMS ((bfd *, asection *, arelent **, asymbol **symbols));
 321 /* ecoff_bfd_reloc_type_lookup defined by backend. */
 322
 323 extern boolean _bfd_ecoff_set_arch_mach
 324   PARAMS ((bfd *, enum bfd_architecture, unsigned long));
 325 extern boolean _bfd_ecoff_set_section_contents
 326   PARAMS ((bfd *, asection *, PTR location, file_ptr, bfd_size_type));
 327
 328 extern int _bfd_ecoff_sizeof_headers PARAMS ((bfd *abfd, boolean reloc));
 329 /* ecoff_bfd_get_relocated_section_contents defined by backend.  */
 330 /* ecoff_bfd_relax_section defined by backend.  */
 331 extern struct bfd_link_hash_table *_bfd_ecoff_bfd_link_hash_table_create
 332   PARAMS ((bfd *));
 333 #define _bfd_ecoff_bfd_link_hash_table_free _bfd_generic_link_hash_table_free
 334 extern boolean _bfd_ecoff_bfd_link_add_symbols
 335   PARAMS ((bfd *, struct bfd_link_info *));
 336 #define _bfd_ecoff_bfd_link_just_syms _bfd_generic_link_just_syms
 337 extern boolean _bfd_ecoff_bfd_final_link
 338   PARAMS ((bfd *, struct bfd_link_info *));
 339
 340 /* Hook functions for the generic COFF section reading code.  */
 341
 342 extern PTR _bfd_ecoff_mkobject_hook PARAMS ((bfd *, PTR filehdr, PTR aouthdr));
 343 #define _bfd_ecoff_set_alignment_hook \
 344   ((void (*) PARAMS ((bfd *, asection *, PTR))) bfd_void)
 345 extern boolean _bfd_ecoff_set_arch_mach_hook PARAMS ((bfd *abfd, PTR filehdr));
 346 extern boolean _bfd_ecoff_styp_to_sec_flags
 347   PARAMS ((bfd *, PTR, const char *, asection *, flagword *));
 348 extern boolean _bfd_ecoff_slurp_symbol_table PARAMS ((bfd *abfd));
 349
 350 /* ECOFF auxiliary information swapping routines.  These are the same
 351    for all ECOFF targets, so they are defined in ecofflink.c.  */
 352
 353 extern void _bfd_ecoff_swap_tir_in
 354   PARAMS ((int, const struct tir_ext *, TIR *));
 355 extern void _bfd_ecoff_swap_tir_out
 356   PARAMS ((int, const TIR *, struct tir_ext *));
 357 extern void _bfd_ecoff_swap_rndx_in
 358   PARAMS ((int, const struct rndx_ext *, RNDXR *));
 359 extern void _bfd_ecoff_swap_rndx_out
 360   PARAMS ((int, const RNDXR *, struct rndx_ext *));