bfd/libecoff.h

   1 /* BFD ECOFF object file private structure.
   2    Copyright (C) 1993 Free Software Foundation, Inc.
   3    Written by Ian Lance Taylor, Cygnus Support.
   4
   5 This file is part of BFD, the Binary File Descriptor library.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #include "bfdlink.h"
  22
  23 #ifndef ECOFF_H
  24 #include "coff/ecoff.h"
  25 #endif
  26
  27 /* This is the backend information kept for ECOFF files.  This
  28    structure is constant for a particular backend.  The first element
  29    is the COFF backend data structure, so that ECOFF targets can use
  30    the generic COFF code.  */
  31
  32 #define ecoff_backend(abfd) \
  33   ((struct ecoff_backend_data *) (abfd)->xvec->backend_data)
  34
  35 struct ecoff_backend_data
  36 {
  37   /* COFF backend information.  This must be the first field.  */
  38   bfd_coff_backend_data coff;
  39   /* Supported architecture.  */
  40   enum bfd_architecture arch;
  41   /* Initial portion of armap string.  */
  42   const char *armap_start;
  43   /* The page boundary used to align sections in a demand-paged
  44      executable file.  E.g., 0x1000.  */
  45   bfd_vma round;
  46   /* True if the .rdata section is part of the text segment, as on the
  47      Alpha.  False if .rdata is part of the data segment, as on the
  48      MIPS.  */
  49   boolean rdata_in_text;
  50   /* Bitsize of constructor entries.  */
  51   unsigned int constructor_bitsize;
  52   /* Reloc to use for constructor entries.  */
  53   CONST struct reloc_howto_struct *constructor_reloc;
  54   /* How to swap debugging information.  */
  55   struct ecoff_debug_swap debug_swap;
  56   /* External reloc size.  */
  57   bfd_size_type external_reloc_size;
  58   /* Reloc swapping functions.  */
  59   void (*swap_reloc_in) PARAMS ((bfd *, PTR, struct internal_reloc *));
  60   void (*swap_reloc_out) PARAMS ((bfd *, const struct internal_reloc *, PTR));
  61   /* Backend reloc tweaking.  */
  62   void (*adjust_reloc_in) PARAMS ((bfd *, const struct internal_reloc *,
  63                                    arelent *));
  64   void (*adjust_reloc_out) PARAMS ((bfd *, const arelent *,
  65                                     struct internal_reloc *));
  66   /* Relocate section contents while linking.  */
  67   boolean (*relocate_section) PARAMS ((bfd *output_bfd, struct bfd_link_info *,
  68                                        bfd *input_bfd, asection *input_section,
  69                                        bfd_byte *contents,
  70                                        PTR external_relocs));
  71 };
  72
  73 /* This is the target specific information kept for ECOFF files.  */
  74
  75 #define ecoff_data(abfd) ((abfd)->tdata.ecoff_obj_data)
  76
  77 typedef struct ecoff_tdata
  78 {
  79   /* The reloc file position, set by
  80      ecoff_compute_section_file_positions.  */
  81   file_ptr reloc_filepos;
  82
  83   /* The symbol table file position, set by ecoff_mkobject_hook.  */
  84   file_ptr sym_filepos;
  85
  86   /* The start and end of the text segment.  Only valid for an
  87      existing file, not for one we are creating.  */
  88   unsigned long text_start;
  89   unsigned long text_end;
  90
  91   /* The cached gp value.  This is used when relocating.  */
  92   bfd_vma gp;
  93
  94   /* The maximum size of objects to optimize using gp.  This is
  95      typically set by the -G option to the compiler, assembler or
  96      linker.  */
  97   int gp_size;
  98
  99   /* The register masks.  When linking, all the masks found in the
 100      input files are combined into the masks of the output file.
 101      These are not all used for all targets, but that's OK, because
 102      the relevant ones are the only ones swapped in and out.  */
 103   unsigned long gprmask;
 104   unsigned long fprmask;
 105   unsigned long cprmask[4];
 106
 107   /* The ECOFF symbolic debugging information.  */
 108   struct ecoff_debug_info debug_info;
 109
 110   /* The unswapped ECOFF symbolic information.  */
 111   PTR raw_syments;
 112
 113   /* The canonical BFD symbols.  */
 114   struct ecoff_symbol_struct *canonical_symbols;
 115
 116   /* A mapping from external symbol numbers to entries in the linker
 117      hash table, used when linking.  */
 118   struct ecoff_link_hash_entry **sym_hashes;
 119
 120   /* A mapping from reloc symbol indices to sections, used when
 121      linking.  */
 122   asection **symndx_to_section;
 123
 124   /* True if this BFD was written by the backend linker.  */
 125   boolean linker;
 126
 127 } ecoff_data_type;
 128
 129 /* Each canonical asymbol really looks like this.  */
 130
 131 typedef struct ecoff_symbol_struct
 132 {
 133   /* The actual symbol which the rest of BFD works with */
 134   asymbol symbol;
 135
 136   /* The fdr for this symbol.  */
 137   FDR *fdr;
 138
 139   /* true if this is a local symbol rather than an external one.  */
 140   boolean local;
 141
 142   /* A pointer to the unswapped hidden information for this symbol.
 143      This is either a struct sym_ext or a struct ext_ext, depending on
 144      the value of the local field above.  */
 145   PTR native;
 146 } ecoff_symbol_type;
 147
 148 /* We take the address of the first element of a asymbol to ensure that the
 149    macro is only ever applied to an asymbol.  */
 150 #define ecoffsymbol(asymbol) ((ecoff_symbol_type *) (&((asymbol)->the_bfd)))
 151
 152 /* This is a hack borrowed from coffcode.h; we need to save the index
 153    of an external symbol when we write it out so that can set the
 154    symbol index correctly when we write out the relocs.  */
 155 #define ecoff_get_sym_index(symbol) ((unsigned long) (symbol)->udata)
 156 #define ecoff_set_sym_index(symbol, idx) ((symbol)->udata = (PTR) (idx))
 157
 158 /* When generating MIPS embedded PIC code, the linker relaxes the code
 159    to turn PC relative branches into longer code sequences when the PC
 160    relative branch is out of range.  This involves reading the relocs
 161    in bfd_relax_section as well as in bfd_final_link, and requires the
 162    code to keep track of which relocs have been expanded.  A pointer
 163    to this structure is put in the used_by_bfd pointer of a section to
 164    keep track of this information.  The user_by_bfd pointer will be
 165    NULL if the information was not needed.  */
 166
 167 struct ecoff_section_tdata
 168 {
 169   /* The unswapped relocs for this section.  These are stored in
 170      memory so the input file does not have to be read twice.  */
 171   PTR external_relocs;
 172
 173   /* The contents of the section.  These bytes may or may not be saved
 174      in memory, but if it is this is a pointer to them.  */
 175   bfd_byte *contents;
 176
 177   /* Offset adjustments for PC relative branches.  A number other than
 178      1 is an addend for a PC relative branch, or a switch table entry
 179      which is the difference of two .text locations; this addend
 180      arises because the branch or difference crosses one or more
 181      branches which were expanded into a larger code sequence.  A 1
 182      means that this branch was itself expanded into a larger code
 183      sequence.  1 is not a possible offset, since all offsets must be
 184      multiples of the instruction size, which is 4; also, the only
 185      relocs with non-zero offsets will be PC relative branches or
 186      switch table entries within the same object file.  If this field
 187      is NULL, no branches were expanded and no offsets are required.
 188      Otherwise there are as many entries as there are relocs in the
 189      section, and the entry for any reloc that is not PC relative is
 190      zero.  */
 191   long *offsets;
 192 };
 193
 194 /* An accessor macro for the ecoff_section_tdata structure.  */
 195 #define ecoff_section_data(abfd, sec) \
 196   ((struct ecoff_section_tdata *) (sec)->used_by_bfd)
 197
 198 /* ECOFF linker hash table entries.  */
 199
 200 struct ecoff_link_hash_entry
 201 {
 202   struct bfd_link_hash_entry root;
 203   /* Symbol index in output file.  */
 204   long indx;
 205   /* BFD that ext field value came from.  */
 206   bfd *abfd;
 207   /* ECOFF external symbol information.  */
 208   EXTR esym;
 209 };
 210
 211 /* ECOFF linker hash table.  */
 212
 213 struct ecoff_link_hash_table
 214 {
 215   struct bfd_link_hash_table root;
 216 };
 217
 218 /* Make an ECOFF object.  */
 219 extern boolean ecoff_mkobject PARAMS ((bfd *));
 220
 221 /* Read in the ECOFF symbolic debugging information.  */
 222 extern boolean ecoff_slurp_symbolic_info PARAMS ((bfd *));
 223
 224 /* Generic ECOFF BFD backend vectors.  */
 225
 226 extern boolean ecoff_write_object_contents PARAMS ((bfd *abfd));
 227 extern bfd_target *ecoff_archive_p PARAMS ((bfd *abfd));
 228
 229 #define ecoff_close_and_cleanup _bfd_generic_close_and_cleanup
 230 #define ecoff_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
 231 extern boolean ecoff_new_section_hook PARAMS ((bfd *abfd,
 232                                                asection *section));
 233 extern boolean ecoff_get_section_contents PARAMS ((bfd *abfd,
 234                                                    asection *section,
 235                                                    PTR location,
 236                                                    file_ptr offset,
 237                                                    bfd_size_type count));
 238
 239 extern boolean ecoff_bfd_copy_private_bfd_data PARAMS ((bfd *, bfd *));
 240 #define ecoff_bfd_copy_private_section_data \
 241   _bfd_generic_bfd_copy_private_section_data
 242
 243 extern boolean ecoff_slurp_armap PARAMS ((bfd *abfd));
 244 #define ecoff_slurp_extended_name_table _bfd_slurp_extended_name_table
 245 #define ecoff_truncate_arname bfd_dont_truncate_arname
 246 extern boolean ecoff_write_armap PARAMS ((bfd *abfd, unsigned int elength,
 247                                           struct orl *map,
 248                                           unsigned int orl_count,
 249                                           int stridx));
 250 #define ecoff_openr_next_archived_file bfd_generic_openr_next_archived_file
 251 #define ecoff_generic_stat_arch_elt bfd_generic_stat_arch_elt
 252
 253 extern long ecoff_get_symtab_upper_bound PARAMS ((bfd *abfd));
 254 extern long ecoff_get_symtab PARAMS ((bfd *abfd, asymbol **alocation));
 255 extern asymbol *ecoff_make_empty_symbol PARAMS ((bfd *abfd));
 256 extern void ecoff_print_symbol PARAMS ((bfd *abfd, PTR filep,
 257                                         asymbol *symbol,
 258                                         bfd_print_symbol_type how));
 259 extern void ecoff_get_symbol_info PARAMS ((bfd *abfd,
 260                                            asymbol *symbol,
 261                                            symbol_info *ret));
 262 #define ecoff_bfd_is_local_label bfd_generic_is_local_label
 263 #define ecoff_get_lineno _bfd_nosymbols_get_lineno
 264 extern boolean ecoff_find_nearest_line PARAMS ((bfd *abfd,
 265                                                 asection *section,
 266                                                 asymbol **symbols,
 267                                                 bfd_vma offset,
 268                                                 CONST char **filename_ptr,
 269                                                 CONST char **fnname_ptr,
 270                                                 unsigned int *retline_ptr));
 271 #define ecoff_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
 272
 273 #define ecoff_get_reloc_upper_bound     coff_get_reloc_upper_bound
 274 extern long ecoff_canonicalize_reloc PARAMS ((bfd *abfd,
 275                                               asection *section,
 276                                               arelent **relptr,
 277                                               asymbol **symbols));
 278 /* ecoff_bfd_reloc_type_lookup defined by backend. */
 279
 280 extern boolean ecoff_set_arch_mach PARAMS ((bfd *abfd,
 281                                             enum bfd_architecture arch,
 282                                             unsigned long machine));
 283 extern boolean ecoff_set_section_contents PARAMS ((bfd *abfd,
 284                                                    asection *section,
 285                                                    PTR location,
 286                                                    file_ptr offset,
 287                                                    bfd_size_type count));
 288
 289 extern int ecoff_sizeof_headers PARAMS ((bfd *abfd, boolean reloc));
 290 /* ecoff_bfd_get_relocated_section_contents defined by backend.  */
 291 /* ecoff_bfd_relax_section defined by backend.  */
 292 extern struct bfd_link_hash_table *ecoff_bfd_link_hash_table_create
 293   PARAMS ((bfd *));
 294 extern boolean ecoff_bfd_link_add_symbols
 295   PARAMS ((bfd *, struct bfd_link_info *));
 296 extern boolean ecoff_bfd_final_link PARAMS ((bfd *, struct bfd_link_info *));
 297
 298 /* Hook functions for the generic COFF section reading code.  */
 299
 300 extern PTR ecoff_mkobject_hook PARAMS ((bfd *, PTR filehdr, PTR aouthdr));
 301 extern asection *ecoff_make_section_hook PARAMS ((bfd *abfd, char *name));
 302 #define ecoff_set_alignment_hook \
 303   ((void (*) PARAMS ((bfd *, asection *, PTR))) bfd_void)
 304 extern boolean ecoff_set_arch_mach_hook PARAMS ((bfd *abfd, PTR filehdr));
 305 extern long ecoff_sec_to_styp_flags PARAMS ((CONST char *name,
 306                                              flagword flags));
 307 extern flagword ecoff_styp_to_sec_flags PARAMS ((bfd *abfd, PTR hdr));
 308 extern boolean ecoff_slurp_symbol_table PARAMS ((bfd *abfd));