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 } ecoff_data_type;
 125
 126 /* Each canonical asymbol really looks like this.  */
 127
 128 typedef struct ecoff_symbol_struct
 129 {
 130   /* The actual symbol which the rest of BFD works with */
 131   asymbol symbol;
 132
 133   /* The fdr for this symbol.  */
 134   FDR *fdr;
 135
 136   /* true if this is a local symbol rather than an external one.  */
 137   boolean local;
 138
 139   /* A pointer to the unswapped hidden information for this symbol.
 140      This is either a struct sym_ext or a struct ext_ext, depending on
 141      the value of the local field above.  */
 142   PTR native;
 143 } ecoff_symbol_type;
 144
 145 /* We take the address of the first element of a asymbol to ensure that the
 146    macro is only ever applied to an asymbol.  */
 147 #define ecoffsymbol(asymbol) ((ecoff_symbol_type *) (&((asymbol)->the_bfd)))
 148
 149 /* This is a hack borrowed from coffcode.h; we need to save the index
 150    of an external symbol when we write it out so that can set the
 151    symbol index correctly when we write out the relocs.  */
 152 #define ecoff_get_sym_index(symbol) ((unsigned long) (symbol)->udata)
 153 #define ecoff_set_sym_index(symbol, idx) ((symbol)->udata = (PTR) (idx))
 154
 155 /* When generating MIPS embedded PIC code, the linker relaxes the code
 156    to turn PC relative branches into longer code sequences when the PC
 157    relative branch is out of range.  This involves reading the relocs
 158    in bfd_relax_section as well as in bfd_final_link, and requires the
 159    code to keep track of which relocs have been expanded.  A pointer
 160    to this structure is put in the used_by_bfd pointer of a section to
 161    keep track of this information.  The user_by_bfd pointer will be
 162    NULL if the information was not needed.  */
 163
 164 struct ecoff_section_tdata
 165 {
 166   /* The unswapped relocs for this section.  These are stored in
 167      memory so the input file does not have to be read twice.  */
 168   PTR external_relocs;
 169
 170   /* The contents of the section.  These bytes may or may not be saved
 171      in memory, but if it is this is a pointer to them.  */
 172   bfd_byte *contents;
 173
 174   /* Offset adjustments for PC relative branches.  A number other than
 175    1 is an addend for a PC relative branch; this addend arises because
 176    it crosses one or more branches which were expanded into a larger
 177    code sequence.  A 1 means that this branch was itself expanded into
 178    a larger code sequence.  1 is not a possible offset, since all
 179    offsets must be multiples of the instruction size, which is 4;
 180    also, the only relocs with non-zero offsets will be PC relative
 181    branches within the same object file.  If this field is NULL, no
 182    branches were expanded and no offsets are required.  Otherwise
 183    there are as many entries as there are relocs in the section, and
 184    the entry for any reloc that is not PC relative is zero.  */
 185   long *offsets;
 186 };
 187
 188 /* An accessor macro for the ecoff_section_tdata structure.  */
 189 #define ecoff_section_data(abfd, sec) \
 190   ((struct ecoff_section_tdata *) (sec)->used_by_bfd)
 191
 192 /* ECOFF linker hash table entries.  */
 193
 194 struct ecoff_link_hash_entry
 195 {
 196   struct bfd_link_hash_entry root;
 197   /* Symbol index in output file.  */
 198   long indx;
 199   /* BFD that ext field value came from.  */
 200   bfd *abfd;
 201   /* ECOFF external symbol information.  */
 202   EXTR esym;
 203 };
 204
 205 /* ECOFF linker hash table.  */
 206
 207 struct ecoff_link_hash_table
 208 {
 209   struct bfd_link_hash_table root;
 210 };
 211
 212 /* Make an ECOFF object.  */
 213 extern boolean ecoff_mkobject PARAMS ((bfd *));
 214
 215 /* Read in the ECOFF symbolic debugging information.  */
 216 extern boolean ecoff_slurp_symbolic_info PARAMS ((bfd *));
 217
 218 /* Generic ECOFF BFD backend vectors.  */
 219
 220 extern boolean ecoff_write_object_contents PARAMS ((bfd *abfd));
 221 extern bfd_target *ecoff_archive_p PARAMS ((bfd *abfd));
 222
 223 #define ecoff_close_and_cleanup _bfd_generic_close_and_cleanup
 224 #define ecoff_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
 225 extern boolean ecoff_new_section_hook PARAMS ((bfd *abfd,
 226                                                asection *section));
 227 extern boolean ecoff_get_section_contents PARAMS ((bfd *abfd,
 228                                                    asection *section,
 229                                                    PTR location,
 230                                                    file_ptr offset,
 231                                                    bfd_size_type count));
 232
 233 #define ecoff_bfd_copy_private_bfd_data _bfd_generic_bfd_copy_private_bfd_data
 234 #define ecoff_bfd_copy_private_section_data \
 235   _bfd_generic_bfd_copy_private_section_data
 236
 237 extern boolean ecoff_slurp_armap PARAMS ((bfd *abfd));
 238 #define ecoff_slurp_extended_name_table _bfd_slurp_extended_name_table
 239 #define ecoff_truncate_arname bfd_dont_truncate_arname
 240 extern boolean ecoff_write_armap PARAMS ((bfd *abfd, unsigned int elength,
 241                                           struct orl *map,
 242                                           unsigned int orl_count,
 243                                           int stridx));
 244 #define ecoff_openr_next_archived_file bfd_generic_openr_next_archived_file
 245 #define ecoff_generic_stat_arch_elt bfd_generic_stat_arch_elt
 246
 247 extern long ecoff_get_symtab_upper_bound PARAMS ((bfd *abfd));
 248 extern long ecoff_get_symtab PARAMS ((bfd *abfd, asymbol **alocation));
 249 extern asymbol *ecoff_make_empty_symbol PARAMS ((bfd *abfd));
 250 extern void ecoff_print_symbol PARAMS ((bfd *abfd, PTR filep,
 251                                         asymbol *symbol,
 252                                         bfd_print_symbol_type how));
 253 extern void ecoff_get_symbol_info PARAMS ((bfd *abfd,
 254                                            asymbol *symbol,
 255                                            symbol_info *ret));
 256 #define ecoff_bfd_is_local_label bfd_generic_is_local_label
 257 #define ecoff_get_lineno _bfd_nosymbols_get_lineno
 258 extern boolean ecoff_find_nearest_line PARAMS ((bfd *abfd,
 259                                                 asection *section,
 260                                                 asymbol **symbols,
 261                                                 bfd_vma offset,
 262                                                 CONST char **filename_ptr,
 263                                                 CONST char **fnname_ptr,
 264                                                 unsigned int *retline_ptr));
 265 #define ecoff_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
 266
 267 #define ecoff_get_reloc_upper_bound     coff_get_reloc_upper_bound
 268 extern long ecoff_canonicalize_reloc PARAMS ((bfd *abfd,
 269                                               asection *section,
 270                                               arelent **relptr,
 271                                               asymbol **symbols));
 272 /* ecoff_bfd_reloc_type_lookup defined by backend. */
 273
 274 extern boolean ecoff_set_arch_mach PARAMS ((bfd *abfd,
 275                                             enum bfd_architecture arch,
 276                                             unsigned long machine));
 277 extern boolean ecoff_set_section_contents PARAMS ((bfd *abfd,
 278                                                    asection *section,
 279                                                    PTR location,
 280                                                    file_ptr offset,
 281                                                    bfd_size_type count));
 282
 283 extern int ecoff_sizeof_headers PARAMS ((bfd *abfd, boolean reloc));
 284 /* ecoff_bfd_get_relocated_section_contents defined by backend.  */
 285 /* ecoff_bfd_relax_section defined by backend.  */
 286 extern struct bfd_link_hash_table *ecoff_bfd_link_hash_table_create
 287   PARAMS ((bfd *));
 288 extern boolean ecoff_bfd_link_add_symbols
 289   PARAMS ((bfd *, struct bfd_link_info *));
 290 extern boolean ecoff_bfd_final_link PARAMS ((bfd *, struct bfd_link_info *));
 291
 292 /* Hook functions for the generic COFF section reading code.  */
 293
 294 extern PTR ecoff_mkobject_hook PARAMS ((bfd *, PTR filehdr, PTR aouthdr));
 295 extern asection *ecoff_make_section_hook PARAMS ((bfd *abfd, char *name));
 296 #define ecoff_set_alignment_hook \
 297   ((void (*) PARAMS ((bfd *, asection *, PTR))) bfd_void)
 298 extern boolean ecoff_set_arch_mach_hook PARAMS ((bfd *abfd, PTR filehdr));
 299 extern long ecoff_sec_to_styp_flags PARAMS ((CONST char *name,
 300                                              flagword flags));
 301 extern flagword ecoff_styp_to_sec_flags PARAMS ((bfd *abfd, PTR hdr));
 302 extern boolean ecoff_slurp_symbol_table PARAMS ((bfd *abfd));