bfd/som.h

   1 /* HP PA-RISC SOM object file format:  definitions internal to BFD.
   2    Copyright (C) 1990, 91, 92, 93, 94 Free Software Foundation, Inc.
   3
   4    Contributed by the Center for Software Science at the
   5    University of Utah (pa-gdb-bugs@cs.utah.edu).
   6
   7    This file is part of BFD, the Binary File Descriptor library.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  22
  23 #ifndef _SOM_H
  24 #define _SOM_H
  25
  26 #include "../bfd/sysdep.h"
  27 #include "libhppa.h"
  28
  29 #include <a.out.h>
  30 #include <lst.h>
  31 #include <ar.h>
  32
  33
  34 #if defined(HOST_HPPABSD) || defined (HOST_HPPAOSF)
  35 /* BSD uses a completely different scheme for object file identification.
  36    so for now, define _PA_RISC_ID to accept any random value for a model
  37    number.  */
  38 #undef _PA_RISC_ID
  39 #define _PA_RISC_ID(__m_num) 1
  40 #endif /* HOST_HPPABSD */
  41
  42 #define FILE_HDR_SIZE sizeof(struct header)
  43 #define AUX_HDR_SIZE sizeof(struct som_exec_auxhdr)
  44
  45 typedef struct som_symbol
  46   {
  47     asymbol symbol;
  48     short desc;
  49     char other;
  50     unsigned char type;
  51     unsigned int som_type;
  52
  53     /* Structured like the ELF tc_data union.  Allows more code sharing
  54        in GAS this way.  */
  55     union
  56       {
  57         unsigned int hppa_arg_reloc;
  58         PTR any;
  59       }
  60     tc_data;
  61
  62     /* Index of this symbol in the symbol table.  Only used when
  63        building relocation streams for incomplete objects.  */
  64     int index;
  65
  66     /* How many times this symbol is used in a relocation.  By sorting
  67        the symbols from most used to least used we can significantly
  68        reduce the size of the relocation stream for incomplete objects.  */
  69     int reloc_count;
  70
  71     /* The unwind descriptor bits associated with R_ENTRY relocations
  72        for functions (not enough room in a BFD reloc to store all the
  73        information, so we tack it onto the symbol associated with the
  74        function.  */
  75     char *unwind;
  76   }
  77 som_symbol_type;
  78
  79 /* A structure containing all the magic information stored in a BFD's
  80    private data which needs to be copied during an objcopy/strip run.  */
  81 struct som_exec_data
  82   {
  83     /* Sort-of a magic number.  BSD uses it to distinguish between
  84        native executables and hpux executables.  */
  85     short system_id;
  86
  87     /* Magic exec flags.  These control things like whether or not
  88        null pointer dereferencing is allowed and the like.  */
  89     long exec_flags;
  90
  91     /* Add more stuff here as needed.  Good examples of information
  92        we might want to pass would be presumed_dp, entry_* and maybe
  93        others from the file header.  */
  94   };
  95
  96 struct somdata
  97   {
  98     /* All the magic information about an executable which lives
  99        in the private BFD structure and needs to be copied from
 100        the input bfd to the output bfd during a objcopy/strip.  */
 101     struct som_exec_data *exec_data;
 102
 103     /* These three fields are only used when writing files and are
 104        generated from scratch.  They need not be copied for objcopy
 105        or strip to work.  */
 106     struct header *file_hdr;
 107     struct copyright_aux_hdr *copyright_aux_hdr;
 108     struct user_string_aux_hdr *version_aux_hdr;
 109
 110     /* Pointers to a saved copy of the symbol and string tables.  These
 111        need not be copied for objcopy or strip to work.  */
 112     som_symbol_type *symtab;
 113     char *stringtab;
 114
 115     /* We remember these offsets so that after check_file_format, we have
 116        no dependencies on the particular format of the exec_hdr.
 117        These offsets need not be copied for objcopy or strip to work.  */
 118
 119     file_ptr sym_filepos;
 120     file_ptr str_filepos;
 121     file_ptr reloc_filepos;
 122     unsigned stringtab_size;
 123   };
 124
 125 struct som_data_struct
 126   {
 127     struct somdata a;
 128   };
 129
 130 /* Substructure of som_section_data_struct used to hold information
 131    which can't be represented by the generic BFD section structure,
 132    but which must be copied during objcopy or strip.  */
 133 struct som_copyable_section_data_struct
 134   {
 135     /* Various fields in space and subspace headers that we need
 136        to pass around.  */
 137     unsigned int sort_key : 8;
 138     unsigned int access_control_bits : 7;
 139     unsigned int is_defined : 1;
 140     unsigned int is_private : 1;
 141     unsigned int quadrant : 2;
 142
 143     /* For subspaces, this points to the section which represents the
 144        space in which the subspace is contained.  For spaces it points
 145        back to the section for this space.  */
 146     asection *container;
 147
 148     /* The user-specified space number.  It is wrong to use this as
 149        an index since duplicates and holes are allowed.  */
 150     int space_number;
 151
 152     /* Add more stuff here as needed.  Good examples of information
 153        we might want to pass would be initialization pointers,
 154        and the many subspace flags we do not represent yet.  */
 155   };
 156
 157 /* Used to keep extra SOM specific information for a given section.
 158
 159    reloc_size holds the size of the relocation stream, note this
 160    is very different from the number of relocations as SOM relocations
 161    are variable length.
 162
 163    reloc_stream is the actual stream of relocation entries.  */
 164
 165 struct som_section_data_struct
 166   {
 167     struct som_copyable_section_data_struct *copy_data;
 168     unsigned int reloc_size;
 169     char *reloc_stream;
 170     struct space_dictionary_record *space_dict;
 171     struct subspace_dictionary_record *subspace_dict;
 172   };
 173
 174 #define somdata(bfd)                    ((bfd)->tdata.som_data->a)
 175 #define obj_som_exec_data(bfd)          (somdata(bfd).exec_data)
 176 #define obj_som_file_hdr(bfd)           (somdata(bfd).file_hdr)
 177 #define obj_som_copyright_hdr(bfd)      (somdata(bfd).copyright_aux_hdr)
 178 #define obj_som_version_hdr(bfd)        (somdata(bfd).version_aux_hdr)
 179 #define obj_som_symtab(bfd)             (somdata(bfd).symtab)
 180 #define obj_som_stringtab(bfd)          (somdata(bfd).stringtab)
 181 #define obj_som_sym_filepos(bfd)        (somdata(bfd).sym_filepos)
 182 #define obj_som_str_filepos(bfd)        (somdata(bfd).str_filepos)
 183 #define obj_som_stringtab_size(bfd)     (somdata(bfd).stringtab_size)
 184 #define obj_som_reloc_filepos(bfd)      (somdata(bfd).reloc_filepos)
 185 #define som_section_data(sec) \
 186   ((struct som_section_data_struct *)sec->used_by_bfd)
 187 #define som_symbol_data(symbol)         ((som_symbol_type *) symbol)
 188
 189
 190 /* Defines groups of basic relocations.  FIXME:  These should
 191    be the only basic relocations created by GAS.  The rest
 192    should be internal to the BFD backend.
 193
 194    The idea is both SOM and ELF define these basic relocation
 195    types so they map into a SOM or ELF specific reloation as
 196    appropriate.  This allows GAS to share much more code
 197    between the two object formats.  */
 198
 199 #define R_HPPA_NONE                     R_NO_RELOCATION
 200 #define R_HPPA                          R_CODE_ONE_SYMBOL
 201 #define R_HPPA_PCREL_CALL               R_PCREL_CALL
 202 #define R_HPPA_GOTOFF                   R_DP_RELATIVE
 203 #define R_HPPA_ENTRY                    R_ENTRY
 204 #define R_HPPA_EXIT                     R_EXIT
 205
 206 /* Exported functions, mostly for use by GAS.  */
 207 boolean bfd_som_set_section_attributes PARAMS ((asection *, int, int,
 208                                                 unsigned int, int));
 209 boolean bfd_som_set_subsection_attributes PARAMS ((asection *, asection *,
 210                                                    int, unsigned int, int));
 211 void bfd_som_set_symbol_type PARAMS ((asymbol *, unsigned int));
 212 void bfd_som_attach_unwind_info PARAMS ((asymbol *, char *));
 213 boolean bfd_som_attach_aux_hdr PARAMS ((bfd *, int, char *));
 214 int ** hppa_som_gen_reloc_type
 215   PARAMS ((bfd *, int, int, enum hppa_reloc_field_selector_type_alt));
 216 #endif /* _SOM_H */