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 _bfd_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   /* Nonzero if this symbol has been written out.  */
 210   char written;
 211   /* Nonzero if this symbol was referred to as small undefined.  */
 212   char small;
 213 };
 214
 215 /* ECOFF linker hash table.  */
 216
 217 struct ecoff_link_hash_table
 218 {
 219   struct bfd_link_hash_table root;
 220 };
 221
 222 /* Make an ECOFF object.  */
 223 extern boolean _bfd_ecoff_mkobject PARAMS ((bfd *));
 224
 225 /* Read in the ECOFF symbolic debugging information.  */
 226 extern boolean _bfd_ecoff_slurp_symbolic_info
 227   PARAMS ((bfd *, asection *, struct ecoff_debug_info *));
 228
 229 /* Generic ECOFF BFD backend vectors.  */
 230
 231 extern boolean _bfd_ecoff_write_object_contents PARAMS ((bfd *abfd));
 232 extern const bfd_target *_bfd_ecoff_archive_p PARAMS ((bfd *abfd));
 233
 234 #define _bfd_ecoff_close_and_cleanup _bfd_generic_close_and_cleanup
 235 #define _bfd_ecoff_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
 236 extern boolean _bfd_ecoff_new_section_hook
 237   PARAMS ((bfd *, asection *));
 238 extern boolean _bfd_ecoff_get_section_contents
 239   PARAMS ((bfd *, asection *, PTR location, file_ptr, bfd_size_type));
 240
 241 extern boolean _bfd_ecoff_bfd_copy_private_bfd_data PARAMS ((bfd *, bfd *));
 242 #define _bfd_ecoff_bfd_copy_private_section_data \
 243   _bfd_generic_bfd_copy_private_section_data
 244
 245 extern boolean _bfd_ecoff_slurp_armap PARAMS ((bfd *abfd));
 246 #define _bfd_ecoff_slurp_extended_name_table _bfd_slurp_extended_name_table
 247 #define _bfd_ecoff_truncate_arname bfd_dont_truncate_arname
 248 extern boolean _bfd_ecoff_write_armap
 249   PARAMS ((bfd *, unsigned int, struct orl *, unsigned int, int));
 250 #define _bfd_ecoff_openr_next_archived_file \
 251   bfd_generic_openr_next_archived_file
 252 #define _bfd_ecoff_generic_stat_arch_elt bfd_generic_stat_arch_elt
 253
 254 extern long _bfd_ecoff_get_symtab_upper_bound PARAMS ((bfd *abfd));
 255 extern long _bfd_ecoff_get_symtab PARAMS ((bfd *abfd, asymbol **alocation));
 256 extern asymbol *_bfd_ecoff_make_empty_symbol PARAMS ((bfd *abfd));
 257 extern void _bfd_ecoff_print_symbol
 258   PARAMS ((bfd *, PTR filep, asymbol *, bfd_print_symbol_type));
 259 extern void _bfd_ecoff_get_symbol_info
 260   PARAMS ((bfd *, asymbol *, symbol_info *));
 261 #define _bfd_ecoff_bfd_is_local_label bfd_generic_is_local_label
 262 #define _bfd_ecoff_get_lineno _bfd_nosymbols_get_lineno
 263 extern boolean _bfd_ecoff_find_nearest_line
 264   PARAMS ((bfd *, asection *, asymbol **, bfd_vma offset,
 265            const char **filename_ptr, const char **fnname_ptr,
 266            unsigned int *retline_ptr));
 267 #define _bfd_ecoff_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
 268
 269 #define _bfd_ecoff_get_reloc_upper_bound coff_get_reloc_upper_bound
 270 extern long _bfd_ecoff_canonicalize_reloc
 271   PARAMS ((bfd *, asection *, arelent **, asymbol **symbols));
 272 /* ecoff_bfd_reloc_type_lookup defined by backend. */
 273
 274 extern boolean _bfd_ecoff_set_arch_mach
 275   PARAMS ((bfd *, enum bfd_architecture, unsigned long machine));
 276 extern boolean _bfd_ecoff_set_section_contents
 277   PARAMS ((bfd *, asection *, PTR location, file_ptr, bfd_size_type));
 278
 279 extern int _bfd_ecoff_sizeof_headers PARAMS ((bfd *abfd, boolean reloc));
 280 /* ecoff_bfd_get_relocated_section_contents defined by backend.  */
 281 /* ecoff_bfd_relax_section defined by backend.  */
 282 extern struct bfd_link_hash_table *_bfd_ecoff_bfd_link_hash_table_create
 283   PARAMS ((bfd *));
 284 extern boolean _bfd_ecoff_bfd_link_add_symbols
 285   PARAMS ((bfd *, struct bfd_link_info *));
 286 extern boolean _bfd_ecoff_bfd_final_link
 287   PARAMS ((bfd *, struct bfd_link_info *));
 288
 289 /* Hook functions for the generic COFF section reading code.  */
 290
 291 extern PTR _bfd_ecoff_mkobject_hook PARAMS ((bfd *, PTR filehdr, PTR aouthdr));
 292 extern asection *_bfd_ecoff_make_section_hook PARAMS ((bfd *abfd, char *name));
 293 #define _bfd_ecoff_set_alignment_hook \
 294   ((void (*) PARAMS ((bfd *, asection *, PTR))) bfd_void)
 295 extern boolean _bfd_ecoff_set_arch_mach_hook PARAMS ((bfd *abfd, PTR filehdr));
 296 extern flagword _bfd_ecoff_styp_to_sec_flags
 297   PARAMS ((bfd *abfd, PTR hdr, const char *name));
 298 extern boolean _bfd_ecoff_slurp_symbol_table PARAMS ((bfd *abfd));