| 1 | /* BFD back-end for Apple M68K COFF A/UX 3.x files. |
| 2 | Copyright 1996 Free Software Foundation, Inc. |
| 3 | Portions written by Richard Henderson <rth@tamu.edu>, |
| 4 | COMMON symbol munging cribbed from cf-m68klynx.c which was |
| 5 | written by Cygnus Support. |
| 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 22 | |
| 23 | #define TARGET_SYM m68kaux_coff_vec |
| 24 | #define TARGET_NAME "coff-m68k-aux" |
| 25 | |
| 26 | #ifndef TARG_AUX |
| 27 | #define TARG_AUX |
| 28 | #endif |
| 29 | |
| 30 | #define COFF_LONG_FILENAMES |
| 31 | |
| 32 | /* 4k pages */ |
| 33 | #define COFF_PAGE_SIZE 0x1000 |
| 34 | |
| 35 | /* On AUX, a STYP_NOLOAD|STYP_BSS section is part of a shared library. */ |
| 36 | #define BSS_NOLOAD_IS_SHARED_LIBRARY |
| 37 | |
| 38 | #define _bfd_m68kcoff_howto_table _bfd_m68kaux_howto_table |
| 39 | #define _bfd_m68kcoff_rtype2howto _bfd_m68kaux_rtype2howto |
| 40 | #define _bfd_m68kcoff_howto2rtype _bfd_m68kaux_howto2rtype |
| 41 | #define _bfd_m68kcoff_reloc_type_lookup _bfd_m68kaux_reloc_type_lookup |
| 42 | |
| 43 | /* Rather than change names lots of places, reuse the same hack */ |
| 44 | #define LYNX_SPECIAL_FN _bfd_m68kaux_special_fn |
| 45 | |
| 46 | #include "bfd.h" |
| 47 | #include "sysdep.h" |
| 48 | |
| 49 | #ifdef ANSI_PROTOTYPES |
| 50 | struct internal_reloc; |
| 51 | struct coff_link_hash_entry; |
| 52 | struct internal_syment; |
| 53 | #endif |
| 54 | |
| 55 | |
| 56 | static bfd_reloc_status_type _bfd_m68kaux_special_fn |
| 57 | PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **)); |
| 58 | static reloc_howto_type *coff_m68k_aux_rtype_to_howto |
| 59 | PARAMS ((bfd *, asection *, struct internal_reloc *, |
| 60 | struct coff_link_hash_entry *, struct internal_syment *, |
| 61 | bfd_vma *)); |
| 62 | static boolean coff_m68k_aux_link_add_one_symbol |
| 63 | PARAMS ((struct bfd_link_info *, bfd *, const char *, flagword, |
| 64 | asection *, bfd_vma, const char *, boolean, boolean, |
| 65 | struct bfd_link_hash_entry **)); |
| 66 | |
| 67 | |
| 68 | #define coff_rtype_to_howto coff_m68k_aux_rtype_to_howto |
| 69 | #define coff_link_add_one_symbol coff_m68k_aux_link_add_one_symbol |
| 70 | |
| 71 | |
| 72 | /* Compute the addend of a reloc. If the reloc is to a common symbol, |
| 73 | the object file contains the value of the common symbol. By the |
| 74 | time this is called, the linker may be using a different symbol |
| 75 | from a different object file with a different value. Therefore, we |
| 76 | hack wildly to locate the original symbol from this file so that we |
| 77 | can make the correct adjustment. This macro sets coffsym to the |
| 78 | symbol from the original file, and uses it to set the addend value |
| 79 | correctly. If this is not a common symbol, the usual addend |
| 80 | calculation is done, except that an additional tweak is needed for |
| 81 | PC relative relocs. |
| 82 | FIXME: This macro refers to symbols and asect; these are from the |
| 83 | calling function, not the macro arguments. */ |
| 84 | |
| 85 | #define CALC_ADDEND(abfd, ptr, reloc, cache_ptr) \ |
| 86 | { \ |
| 87 | coff_symbol_type *coffsym = (coff_symbol_type *) NULL; \ |
| 88 | if (ptr && bfd_asymbol_bfd (ptr) != abfd) \ |
| 89 | coffsym = (obj_symbols (abfd) \ |
| 90 | + (cache_ptr->sym_ptr_ptr - symbols)); \ |
| 91 | else if (ptr) \ |
| 92 | coffsym = coff_symbol_from (abfd, ptr); \ |
| 93 | if (coffsym != (coff_symbol_type *) NULL \ |
| 94 | && coffsym->native->u.syment.n_scnum == 0) \ |
| 95 | cache_ptr->addend = - coffsym->native->u.syment.n_value; \ |
| 96 | else if (ptr && bfd_asymbol_bfd (ptr) == abfd \ |
| 97 | && ptr->section != (asection *) NULL) \ |
| 98 | cache_ptr->addend = - (ptr->section->vma + ptr->value); \ |
| 99 | else \ |
| 100 | cache_ptr->addend = 0; \ |
| 101 | if (ptr && (reloc.r_type == R_PCRBYTE \ |
| 102 | || reloc.r_type == R_PCRWORD \ |
| 103 | || reloc.r_type == R_PCRLONG)) \ |
| 104 | cache_ptr->addend += asect->vma; \ |
| 105 | } |
| 106 | |
| 107 | |
| 108 | |
| 109 | #include "coff/aux.h" /* override coff/internal.h and coff/m68k.h */ |
| 110 | #include "coff-m68k.c" |
| 111 | |
| 112 | |
| 113 | |
| 114 | /* For some reason when using m68k COFF the value stored in the .text |
| 115 | section for a reference to a common symbol is the value itself plus |
| 116 | any desired offset. (taken from work done by Ian Taylor, Cygnus Support, |
| 117 | for I386 COFF). */ |
| 118 | |
| 119 | /* If we are producing relocateable output, we need to do some |
| 120 | adjustments to the object file that are not done by the |
| 121 | bfd_perform_relocation function. This function is called by every |
| 122 | reloc type to make any required adjustments. */ |
| 123 | |
| 124 | static bfd_reloc_status_type |
| 125 | _bfd_m68kaux_special_fn (abfd, reloc_entry, symbol, data, input_section, |
| 126 | output_bfd, error_message) |
| 127 | bfd *abfd; |
| 128 | arelent *reloc_entry; |
| 129 | asymbol *symbol; |
| 130 | PTR data; |
| 131 | asection *input_section; |
| 132 | bfd *output_bfd; |
| 133 | char **error_message; |
| 134 | { |
| 135 | symvalue diff; |
| 136 | |
| 137 | if (output_bfd == (bfd *) NULL) |
| 138 | return bfd_reloc_continue; |
| 139 | |
| 140 | if (bfd_is_com_section (symbol->section)) |
| 141 | { |
| 142 | /* We are relocating a common symbol. The current value in the |
| 143 | object file is ORIG + OFFSET, where ORIG is the value of the |
| 144 | common symbol as seen by the object file when it was compiled |
| 145 | (this may be zero if the symbol was undefined) and OFFSET is |
| 146 | the offset into the common symbol (normally zero, but may be |
| 147 | non-zero when referring to a field in a common structure). |
| 148 | ORIG is the negative of reloc_entry->addend, which is set by |
| 149 | the CALC_ADDEND macro below. We want to replace the value in |
| 150 | the object file with NEW + OFFSET, where NEW is the value of |
| 151 | the common symbol which we are going to put in the final |
| 152 | object file. NEW is symbol->value. */ |
| 153 | diff = symbol->value + reloc_entry->addend; |
| 154 | } |
| 155 | else |
| 156 | { |
| 157 | /* For some reason bfd_perform_relocation always effectively |
| 158 | ignores the addend for a COFF target when producing |
| 159 | relocateable output. This seems to be always wrong for 386 |
| 160 | COFF, so we handle the addend here instead. */ |
| 161 | diff = reloc_entry->addend; |
| 162 | } |
| 163 | |
| 164 | #define DOIT(x) \ |
| 165 | x = ((x & ~howto->dst_mask) | \ |
| 166 | (((x & howto->src_mask) + diff) & howto->dst_mask)) |
| 167 | |
| 168 | if (diff != 0) |
| 169 | { |
| 170 | reloc_howto_type *howto = reloc_entry->howto; |
| 171 | unsigned char *addr = (unsigned char *) data + reloc_entry->address; |
| 172 | |
| 173 | switch (howto->size) |
| 174 | { |
| 175 | case 0: |
| 176 | { |
| 177 | char x = bfd_get_8 (abfd, addr); |
| 178 | DOIT (x); |
| 179 | bfd_put_8 (abfd, x, addr); |
| 180 | } |
| 181 | break; |
| 182 | |
| 183 | case 1: |
| 184 | { |
| 185 | short x = bfd_get_16 (abfd, addr); |
| 186 | DOIT (x); |
| 187 | bfd_put_16 (abfd, x, addr); |
| 188 | } |
| 189 | break; |
| 190 | |
| 191 | case 2: |
| 192 | { |
| 193 | long x = bfd_get_32 (abfd, addr); |
| 194 | DOIT (x); |
| 195 | bfd_put_32 (abfd, x, addr); |
| 196 | } |
| 197 | break; |
| 198 | |
| 199 | default: |
| 200 | abort (); |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | /* Now let bfd_perform_relocation finish everything up. */ |
| 205 | return bfd_reloc_continue; |
| 206 | } |
| 207 | |
| 208 | |
| 209 | /* coff-m68k.c uses the special COFF backend linker. We need to |
| 210 | adjust common symbols. */ |
| 211 | |
| 212 | /*ARGSUSED*/ |
| 213 | static reloc_howto_type * |
| 214 | coff_m68k_aux_rtype_to_howto (abfd, sec, rel, h, sym, addendp) |
| 215 | bfd *abfd; |
| 216 | asection *sec; |
| 217 | struct internal_reloc *rel; |
| 218 | struct coff_link_hash_entry *h; |
| 219 | struct internal_syment *sym; |
| 220 | bfd_vma *addendp; |
| 221 | { |
| 222 | arelent relent; |
| 223 | reloc_howto_type *howto; |
| 224 | |
| 225 | RTYPE2HOWTO (&relent, rel); |
| 226 | |
| 227 | howto = relent.howto; |
| 228 | |
| 229 | if (sym != NULL && sym->n_scnum == 0 && sym->n_value != 0) |
| 230 | { |
| 231 | /* This is a common symbol. The section contents include the |
| 232 | size (sym->n_value) as an addend. The relocate_section |
| 233 | function will be adding in the final value of the symbol. We |
| 234 | need to subtract out the current size in order to get the |
| 235 | correct result. */ |
| 236 | BFD_ASSERT (h != NULL); |
| 237 | *addendp -= sym->n_value; |
| 238 | } |
| 239 | |
| 240 | /* If the output symbol is common (in which case this must be a |
| 241 | relocateable link), we need to add in the final size of the |
| 242 | common symbol. */ |
| 243 | if (h != NULL && h->root.type == bfd_link_hash_common) |
| 244 | *addendp += h->root.u.c.size; |
| 245 | |
| 246 | return howto; |
| 247 | } |
| 248 | |
| 249 | |
| 250 | /* We need non-absolute symbols to override absolute symbols. This |
| 251 | mirrors Apple's "solution" to let a static library symbol override |
| 252 | a shared library symbol. On the whole not a good thing, given how |
| 253 | shared libraries work here, but can work if you are careful with |
| 254 | what you include in the shared object. */ |
| 255 | |
| 256 | boolean |
| 257 | coff_m68k_aux_link_add_one_symbol (info, abfd, name, flags, section, value, |
| 258 | string, copy, collect, hashp) |
| 259 | struct bfd_link_info *info; |
| 260 | bfd *abfd; |
| 261 | const char *name; |
| 262 | flagword flags; |
| 263 | asection *section; |
| 264 | bfd_vma value; |
| 265 | const char *string; |
| 266 | boolean copy; |
| 267 | boolean collect; |
| 268 | struct bfd_link_hash_entry **hashp; |
| 269 | { |
| 270 | struct bfd_link_hash_entry *h; |
| 271 | |
| 272 | if ((flags & (BSF_WARNING | BSF_CONSTRUCTOR | BSF_WEAK)) == 0 && |
| 273 | !bfd_is_und_section (section) && |
| 274 | !bfd_is_com_section (section)) |
| 275 | { |
| 276 | /* The new symbol is a definition or an indirect definition */ |
| 277 | |
| 278 | /* This bit copied from linker.c */ |
| 279 | if (hashp != NULL && *hashp != NULL) |
| 280 | { |
| 281 | h = *hashp; |
| 282 | BFD_ASSERT (strcmp (h->root.string, name) == 0); |
| 283 | } |
| 284 | else |
| 285 | { |
| 286 | h = bfd_link_hash_lookup (info->hash, name, true, copy, false); |
| 287 | if (h == NULL) |
| 288 | { |
| 289 | if (hashp != NULL) |
| 290 | *hashp = NULL; |
| 291 | return false; |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | if (info->notice_hash != (struct bfd_hash_table *) NULL |
| 296 | && (bfd_hash_lookup (info->notice_hash, name, false, false) |
| 297 | != (struct bfd_hash_entry *) NULL)) |
| 298 | { |
| 299 | if (! (*info->callbacks->notice) (info, name, abfd, section, value)) |
| 300 | return false; |
| 301 | } |
| 302 | |
| 303 | if (hashp != (struct bfd_link_hash_entry **) NULL) |
| 304 | *hashp = h; |
| 305 | /* end duplication from linker.c */ |
| 306 | |
| 307 | if (h->type == bfd_link_hash_defined |
| 308 | || h->type == bfd_link_hash_indirect) |
| 309 | { |
| 310 | asection *msec; |
| 311 | |
| 312 | if (h->type == bfd_link_hash_defined) |
| 313 | msec = h->u.def.section; |
| 314 | else |
| 315 | msec = bfd_ind_section_ptr; |
| 316 | |
| 317 | if (bfd_is_abs_section (msec) && !bfd_is_abs_section (section)) |
| 318 | { |
| 319 | h->u.def.section = section; |
| 320 | h->u.def.value = value; |
| 321 | return true; |
| 322 | } |
| 323 | else if (bfd_is_abs_section (section) && !bfd_is_abs_section (msec)) |
| 324 | return true; |
| 325 | } |
| 326 | } |
| 327 | |
| 328 | /* If we didn't exit early, finish processing in the generic routine */ |
| 329 | return _bfd_generic_link_add_one_symbol (info, abfd, name, flags, section, |
| 330 | value, string, copy, collect, |
| 331 | hashp); |
| 332 | } |