| 1 | # This shell script emits a C file. -*- C -*- |
| 2 | # Copyright 2002, 2003, 2004 Free Software Foundation, Inc. |
| 3 | # |
| 4 | # This file is part of GLD, the Gnu Linker. |
| 5 | # |
| 6 | # This program is free software; you can redistribute it and/or modify |
| 7 | # it under the terms of the GNU General Public License as published by |
| 8 | # the Free Software Foundation; either version 2 of the License, or |
| 9 | # (at your option) any later version. |
| 10 | # |
| 11 | # This program is distributed in the hope that it will be useful, |
| 12 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | # GNU General Public License for more details. |
| 15 | # |
| 16 | # You should have received a copy of the GNU General Public License |
| 17 | # along with this program; if not, write to the Free Software |
| 18 | # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 19 | # |
| 20 | |
| 21 | # This file is sourced from elf32.em, and defines extra powerpc64-elf |
| 22 | # specific routines. |
| 23 | # |
| 24 | cat >>e${EMULATION_NAME}.c <<EOF |
| 25 | |
| 26 | #include "ldctor.h" |
| 27 | #include "libbfd.h" |
| 28 | #include "elf-bfd.h" |
| 29 | #include "elf64-ppc.h" |
| 30 | |
| 31 | /* Fake input file for stubs. */ |
| 32 | static lang_input_statement_type *stub_file; |
| 33 | static int stub_added = 0; |
| 34 | |
| 35 | /* Whether we need to call ppc_layout_sections_again. */ |
| 36 | static int need_laying_out = 0; |
| 37 | |
| 38 | /* Maximum size of a group of input sections that can be handled by |
| 39 | one stub section. A value of +/-1 indicates the bfd back-end |
| 40 | should use a suitable default size. */ |
| 41 | static bfd_signed_vma group_size = 1; |
| 42 | |
| 43 | /* Whether to add ".foo" entries for each "foo" in a version script. */ |
| 44 | static int dotsyms = 1; |
| 45 | |
| 46 | /* Whether to run tls optimization. */ |
| 47 | static int notlsopt = 0; |
| 48 | |
| 49 | /* Whether to emit symbols for stubs. */ |
| 50 | static int emit_stub_syms = 0; |
| 51 | |
| 52 | static asection *toc_section = 0; |
| 53 | |
| 54 | |
| 55 | /* This is called before the input files are opened. We create a new |
| 56 | fake input file to hold the stub sections. */ |
| 57 | |
| 58 | static void |
| 59 | ppc_create_output_section_statements (void) |
| 60 | { |
| 61 | extern const bfd_target bfd_elf64_powerpc_vec; |
| 62 | extern const bfd_target bfd_elf64_powerpcle_vec; |
| 63 | |
| 64 | if (link_info.hash->creator != &bfd_elf64_powerpc_vec |
| 65 | && link_info.hash->creator != &bfd_elf64_powerpcle_vec) |
| 66 | return; |
| 67 | |
| 68 | link_info.wrap_char = '.'; |
| 69 | |
| 70 | stub_file = lang_add_input_file ("linker stubs", |
| 71 | lang_input_file_is_fake_enum, |
| 72 | NULL); |
| 73 | stub_file->the_bfd = bfd_create ("linker stubs", output_bfd); |
| 74 | if (stub_file->the_bfd == NULL |
| 75 | || !bfd_set_arch_mach (stub_file->the_bfd, |
| 76 | bfd_get_arch (output_bfd), |
| 77 | bfd_get_mach (output_bfd))) |
| 78 | { |
| 79 | einfo ("%X%P: can not create BFD %E\n"); |
| 80 | return; |
| 81 | } |
| 82 | |
| 83 | ldlang_add_file (stub_file); |
| 84 | ppc64_elf_init_stub_bfd (stub_file->the_bfd, &link_info); |
| 85 | } |
| 86 | |
| 87 | static void |
| 88 | ppc_after_open (void) |
| 89 | { |
| 90 | if (!ppc64_elf_mark_entry_syms (&link_info)) |
| 91 | { |
| 92 | einfo ("%X%P: can not mark entry symbols %E\n"); |
| 93 | return; |
| 94 | } |
| 95 | |
| 96 | gld${EMULATION_NAME}_after_open (); |
| 97 | } |
| 98 | |
| 99 | static void |
| 100 | ppc_before_allocation (void) |
| 101 | { |
| 102 | if (stub_file != NULL) |
| 103 | { |
| 104 | if (!ppc64_elf_edit_opd (output_bfd, &link_info)) |
| 105 | { |
| 106 | einfo ("%X%P: can not edit opd %E\n"); |
| 107 | return; |
| 108 | } |
| 109 | |
| 110 | if (ppc64_elf_tls_setup (output_bfd, &link_info) && !notlsopt) |
| 111 | { |
| 112 | /* Size the sections. This is premature, but we want to know the |
| 113 | TLS segment layout so that certain optimizations can be done. */ |
| 114 | lang_size_sections (stat_ptr->head, abs_output_section, |
| 115 | &stat_ptr->head, 0, 0, NULL, TRUE); |
| 116 | |
| 117 | if (!ppc64_elf_tls_optimize (output_bfd, &link_info)) |
| 118 | { |
| 119 | einfo ("%X%P: TLS problem %E\n"); |
| 120 | return; |
| 121 | } |
| 122 | |
| 123 | /* We must not cache anything from the preliminary sizing. */ |
| 124 | elf_tdata (output_bfd)->program_header_size = 0; |
| 125 | lang_reset_memory_regions (); |
| 126 | } |
| 127 | } |
| 128 | |
| 129 | gld${EMULATION_NAME}_before_allocation (); |
| 130 | } |
| 131 | |
| 132 | struct hook_stub_info |
| 133 | { |
| 134 | lang_statement_list_type add; |
| 135 | asection *input_section; |
| 136 | }; |
| 137 | |
| 138 | /* Traverse the linker tree to find the spot where the stub goes. */ |
| 139 | |
| 140 | static bfd_boolean |
| 141 | hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp) |
| 142 | { |
| 143 | lang_statement_union_type *l; |
| 144 | bfd_boolean ret; |
| 145 | |
| 146 | for (; (l = *lp) != NULL; lp = &l->header.next) |
| 147 | { |
| 148 | switch (l->header.type) |
| 149 | { |
| 150 | case lang_constructors_statement_enum: |
| 151 | ret = hook_in_stub (info, &constructor_list.head); |
| 152 | if (ret) |
| 153 | return ret; |
| 154 | break; |
| 155 | |
| 156 | case lang_output_section_statement_enum: |
| 157 | ret = hook_in_stub (info, |
| 158 | &l->output_section_statement.children.head); |
| 159 | if (ret) |
| 160 | return ret; |
| 161 | break; |
| 162 | |
| 163 | case lang_wild_statement_enum: |
| 164 | ret = hook_in_stub (info, &l->wild_statement.children.head); |
| 165 | if (ret) |
| 166 | return ret; |
| 167 | break; |
| 168 | |
| 169 | case lang_group_statement_enum: |
| 170 | ret = hook_in_stub (info, &l->group_statement.children.head); |
| 171 | if (ret) |
| 172 | return ret; |
| 173 | break; |
| 174 | |
| 175 | case lang_input_section_enum: |
| 176 | if (l->input_section.section == info->input_section) |
| 177 | { |
| 178 | /* We've found our section. Insert the stub immediately |
| 179 | before its associated input section. */ |
| 180 | *lp = info->add.head; |
| 181 | *(info->add.tail) = l; |
| 182 | return TRUE; |
| 183 | } |
| 184 | break; |
| 185 | |
| 186 | case lang_data_statement_enum: |
| 187 | case lang_reloc_statement_enum: |
| 188 | case lang_object_symbols_statement_enum: |
| 189 | case lang_output_statement_enum: |
| 190 | case lang_target_statement_enum: |
| 191 | case lang_input_statement_enum: |
| 192 | case lang_assignment_statement_enum: |
| 193 | case lang_padding_statement_enum: |
| 194 | case lang_address_statement_enum: |
| 195 | case lang_fill_statement_enum: |
| 196 | break; |
| 197 | |
| 198 | default: |
| 199 | FAIL (); |
| 200 | break; |
| 201 | } |
| 202 | } |
| 203 | return FALSE; |
| 204 | } |
| 205 | |
| 206 | |
| 207 | /* Call-back for ppc64_elf_size_stubs. */ |
| 208 | |
| 209 | /* Create a new stub section, and arrange for it to be linked |
| 210 | immediately before INPUT_SECTION. */ |
| 211 | |
| 212 | static asection * |
| 213 | ppc_add_stub_section (const char *stub_sec_name, asection *input_section) |
| 214 | { |
| 215 | asection *stub_sec; |
| 216 | flagword flags; |
| 217 | asection *output_section; |
| 218 | const char *secname; |
| 219 | lang_output_section_statement_type *os; |
| 220 | struct hook_stub_info info; |
| 221 | |
| 222 | stub_sec = bfd_make_section_anyway (stub_file->the_bfd, stub_sec_name); |
| 223 | if (stub_sec == NULL) |
| 224 | goto err_ret; |
| 225 | |
| 226 | flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE |
| 227 | | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP); |
| 228 | if (!bfd_set_section_flags (stub_file->the_bfd, stub_sec, flags)) |
| 229 | goto err_ret; |
| 230 | |
| 231 | output_section = input_section->output_section; |
| 232 | secname = bfd_get_section_name (output_section->owner, output_section); |
| 233 | os = lang_output_section_find (secname); |
| 234 | |
| 235 | info.input_section = input_section; |
| 236 | lang_list_init (&info.add); |
| 237 | lang_add_section (&info.add, stub_sec, os, stub_file); |
| 238 | |
| 239 | if (info.add.head == NULL) |
| 240 | goto err_ret; |
| 241 | |
| 242 | stub_added = 1; |
| 243 | if (hook_in_stub (&info, &os->children.head)) |
| 244 | return stub_sec; |
| 245 | |
| 246 | err_ret: |
| 247 | einfo ("%X%P: can not make stub section: %E\n"); |
| 248 | return NULL; |
| 249 | } |
| 250 | |
| 251 | |
| 252 | /* Another call-back for ppc64_elf_size_stubs. */ |
| 253 | |
| 254 | static void |
| 255 | ppc_layout_sections_again (void) |
| 256 | { |
| 257 | /* If we have changed sizes of the stub sections, then we need |
| 258 | to recalculate all the section offsets. This may mean we need to |
| 259 | add even more stubs. */ |
| 260 | need_laying_out = 0; |
| 261 | |
| 262 | lang_reset_memory_regions (); |
| 263 | |
| 264 | /* Resize the sections. */ |
| 265 | lang_size_sections (stat_ptr->head, abs_output_section, |
| 266 | &stat_ptr->head, 0, 0, NULL, TRUE); |
| 267 | |
| 268 | /* Recalculate TOC base. */ |
| 269 | ldemul_after_allocation (); |
| 270 | |
| 271 | /* Do the assignments again. */ |
| 272 | lang_do_assignments (stat_ptr->head, abs_output_section, NULL, 0); |
| 273 | } |
| 274 | |
| 275 | |
| 276 | /* Call the back-end function to set TOC base after we have placed all |
| 277 | the sections. */ |
| 278 | static void |
| 279 | gld${EMULATION_NAME}_after_allocation (void) |
| 280 | { |
| 281 | if (!link_info.relocatable) |
| 282 | _bfd_set_gp_value (output_bfd, ppc64_elf_toc (output_bfd)); |
| 283 | } |
| 284 | |
| 285 | |
| 286 | static void |
| 287 | build_toc_list (lang_statement_union_type *statement) |
| 288 | { |
| 289 | if (statement->header.type == lang_input_section_enum |
| 290 | && !statement->input_section.ifile->just_syms_flag |
| 291 | && (statement->input_section.section->flags & SEC_EXCLUDE) == 0 |
| 292 | && statement->input_section.section->output_section == toc_section) |
| 293 | ppc64_elf_next_toc_section (&link_info, statement->input_section.section); |
| 294 | } |
| 295 | |
| 296 | |
| 297 | static void |
| 298 | build_section_lists (lang_statement_union_type *statement) |
| 299 | { |
| 300 | if (statement->header.type == lang_input_section_enum |
| 301 | && !statement->input_section.ifile->just_syms_flag |
| 302 | && (statement->input_section.section->flags & SEC_EXCLUDE) == 0 |
| 303 | && statement->input_section.section->output_section != NULL |
| 304 | && statement->input_section.section->output_section->owner == output_bfd) |
| 305 | { |
| 306 | if (!ppc64_elf_next_input_section (&link_info, |
| 307 | statement->input_section.section)) |
| 308 | einfo ("%X%P: can not size stub section: %E\n"); |
| 309 | } |
| 310 | } |
| 311 | |
| 312 | |
| 313 | /* Final emulation specific call. */ |
| 314 | |
| 315 | static void |
| 316 | gld${EMULATION_NAME}_finish (void) |
| 317 | { |
| 318 | /* e_entry on PowerPC64 points to the function descriptor for |
| 319 | _start. If _start is missing, default to the first function |
| 320 | descriptor in the .opd section. */ |
| 321 | entry_section = ".opd"; |
| 322 | |
| 323 | /* bfd_elf_discard_info just plays with debugging sections, |
| 324 | ie. doesn't affect any code, so we can delay resizing the |
| 325 | sections. It's likely we'll resize everything in the process of |
| 326 | adding stubs. */ |
| 327 | if (bfd_elf_discard_info (output_bfd, &link_info)) |
| 328 | need_laying_out = 1; |
| 329 | |
| 330 | /* If generating a relocatable output file, then we don't have any |
| 331 | stubs. */ |
| 332 | if (stub_file != NULL && !link_info.relocatable) |
| 333 | { |
| 334 | int ret = ppc64_elf_setup_section_lists (output_bfd, &link_info); |
| 335 | if (ret != 0) |
| 336 | { |
| 337 | if (ret < 0) |
| 338 | { |
| 339 | einfo ("%X%P: can not size stub section: %E\n"); |
| 340 | return; |
| 341 | } |
| 342 | |
| 343 | toc_section = bfd_get_section_by_name (output_bfd, ".got"); |
| 344 | if (toc_section != NULL) |
| 345 | lang_for_each_statement (build_toc_list); |
| 346 | |
| 347 | ppc64_elf_reinit_toc (output_bfd, &link_info); |
| 348 | |
| 349 | lang_for_each_statement (build_section_lists); |
| 350 | |
| 351 | /* Call into the BFD backend to do the real work. */ |
| 352 | if (!ppc64_elf_size_stubs (output_bfd, |
| 353 | &link_info, |
| 354 | group_size, |
| 355 | &ppc_add_stub_section, |
| 356 | &ppc_layout_sections_again)) |
| 357 | { |
| 358 | einfo ("%X%P: can not size stub section: %E\n"); |
| 359 | return; |
| 360 | } |
| 361 | } |
| 362 | } |
| 363 | |
| 364 | if (need_laying_out) |
| 365 | ppc_layout_sections_again (); |
| 366 | |
| 367 | if (stub_added) |
| 368 | { |
| 369 | char *msg = NULL; |
| 370 | char *line, *endline; |
| 371 | |
| 372 | if (!ppc64_elf_build_stubs (emit_stub_syms, &link_info, |
| 373 | config.stats ? &msg : NULL)) |
| 374 | einfo ("%X%P: can not build stubs: %E\n"); |
| 375 | |
| 376 | for (line = msg; line != NULL; line = endline) |
| 377 | { |
| 378 | endline = strchr (line, '\n'); |
| 379 | if (endline != NULL) |
| 380 | *endline++ = '\0'; |
| 381 | fprintf (stderr, "%s: %s\n", program_name, line); |
| 382 | } |
| 383 | if (msg != NULL) |
| 384 | free (msg); |
| 385 | } |
| 386 | } |
| 387 | |
| 388 | |
| 389 | /* Add a pattern matching ".foo" for every "foo" in a version script. |
| 390 | |
| 391 | The reason for doing this is that many shared library version |
| 392 | scripts export a selected set of functions or data symbols, forcing |
| 393 | others local. eg. |
| 394 | |
| 395 | . VERS_1 { |
| 396 | . global: |
| 397 | . this; that; some; thing; |
| 398 | . local: |
| 399 | . *; |
| 400 | . }; |
| 401 | |
| 402 | To make the above work for PowerPC64, we need to export ".this", |
| 403 | ".that" and so on, otherwise only the function descriptor syms are |
| 404 | exported. Lack of an exported function code sym may cause a |
| 405 | definition to be pulled in from a static library. */ |
| 406 | |
| 407 | static struct bfd_elf_version_expr * |
| 408 | gld${EMULATION_NAME}_new_vers_pattern (struct bfd_elf_version_expr *entry) |
| 409 | { |
| 410 | struct bfd_elf_version_expr *dot_entry; |
| 411 | unsigned int len; |
| 412 | char *dot_pat; |
| 413 | |
| 414 | if (!dotsyms || entry->pattern[0] == '*' || entry->pattern[0] == '.') |
| 415 | return entry; |
| 416 | |
| 417 | dot_entry = xmalloc (sizeof *dot_entry); |
| 418 | *dot_entry = *entry; |
| 419 | dot_entry->next = entry; |
| 420 | len = strlen (entry->pattern) + 2; |
| 421 | dot_pat = xmalloc (len); |
| 422 | dot_pat[0] = '.'; |
| 423 | memcpy (dot_pat + 1, entry->pattern, len - 1); |
| 424 | dot_entry->pattern = dot_pat; |
| 425 | return dot_entry; |
| 426 | } |
| 427 | |
| 428 | |
| 429 | /* Avoid processing the fake stub_file in vercheck, stat_needed and |
| 430 | check_needed routines. */ |
| 431 | |
| 432 | static void (*real_func) (lang_input_statement_type *); |
| 433 | |
| 434 | static void ppc_for_each_input_file_wrapper (lang_input_statement_type *l) |
| 435 | { |
| 436 | if (l != stub_file) |
| 437 | (*real_func) (l); |
| 438 | } |
| 439 | |
| 440 | static void |
| 441 | ppc_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) |
| 442 | { |
| 443 | real_func = func; |
| 444 | lang_for_each_input_file (&ppc_for_each_input_file_wrapper); |
| 445 | } |
| 446 | |
| 447 | #define lang_for_each_input_file ppc_lang_for_each_input_file |
| 448 | |
| 449 | EOF |
| 450 | |
| 451 | # Define some shell vars to insert bits of code into the standard elf |
| 452 | # parse_args and list_options functions. |
| 453 | # |
| 454 | PARSE_AND_LIST_PROLOGUE=' |
| 455 | #define OPTION_STUBGROUP_SIZE 301 |
| 456 | #define OPTION_STUBSYMS (OPTION_STUBGROUP_SIZE + 1) |
| 457 | #define OPTION_DOTSYMS (OPTION_STUBSYMS + 1) |
| 458 | #define OPTION_NO_DOTSYMS (OPTION_DOTSYMS + 1) |
| 459 | #define OPTION_NO_TLS_OPT (OPTION_NO_DOTSYMS + 1) |
| 460 | ' |
| 461 | |
| 462 | PARSE_AND_LIST_LONGOPTS=' |
| 463 | { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE }, |
| 464 | { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS }, |
| 465 | { "dotsyms", no_argument, NULL, OPTION_DOTSYMS }, |
| 466 | { "no-dotsyms", no_argument, NULL, OPTION_NO_DOTSYMS }, |
| 467 | { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT }, |
| 468 | ' |
| 469 | |
| 470 | PARSE_AND_LIST_OPTIONS=' |
| 471 | fprintf (file, _("\ |
| 472 | --stub-group-size=N Maximum size of a group of input sections that can be\n\ |
| 473 | handled by one stub section. A negative value\n\ |
| 474 | locates all stubs before their branches (with a\n\ |
| 475 | group size of -N), while a positive value allows\n\ |
| 476 | two groups of input sections, one before, and one\n\ |
| 477 | after each stub section. Values of +/-1 indicate\n\ |
| 478 | the linker should choose suitable defaults.\n" |
| 479 | )); |
| 480 | fprintf (file, _("\ |
| 481 | --emit-stub-syms Label linker stubs with a symbol.\n" |
| 482 | )); |
| 483 | fprintf (file, _("\ |
| 484 | --dotsyms For every version pattern \"foo\" in a version script,\n\ |
| 485 | add \".foo\" so that function code symbols are\n\ |
| 486 | treated the same as function descriptor symbols.\n\ |
| 487 | Defaults to on.\n" |
| 488 | )); |
| 489 | fprintf (file, _("\ |
| 490 | --no-dotsyms Don'\''t do anything special in version scripts.\n" |
| 491 | )); |
| 492 | fprintf (file, _("\ |
| 493 | --no-tls-optimize Don'\''t try to optimize TLS accesses.\n" |
| 494 | )); |
| 495 | ' |
| 496 | |
| 497 | PARSE_AND_LIST_ARGS_CASES=' |
| 498 | case OPTION_STUBGROUP_SIZE: |
| 499 | { |
| 500 | const char *end; |
| 501 | group_size = bfd_scan_vma (optarg, &end, 0); |
| 502 | if (*end) |
| 503 | einfo (_("%P%F: invalid number `%s'\''\n"), optarg); |
| 504 | } |
| 505 | break; |
| 506 | |
| 507 | case OPTION_STUBSYMS: |
| 508 | emit_stub_syms = 1; |
| 509 | break; |
| 510 | |
| 511 | case OPTION_DOTSYMS: |
| 512 | dotsyms = 1; |
| 513 | break; |
| 514 | |
| 515 | case OPTION_NO_DOTSYMS: |
| 516 | dotsyms = 0; |
| 517 | break; |
| 518 | |
| 519 | case OPTION_NO_TLS_OPT: |
| 520 | notlsopt = 1; |
| 521 | break; |
| 522 | ' |
| 523 | |
| 524 | # Put these extra ppc64elf routines in ld_${EMULATION_NAME}_emulation |
| 525 | # |
| 526 | LDEMUL_AFTER_OPEN=ppc_after_open |
| 527 | LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation |
| 528 | LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation |
| 529 | LDEMUL_FINISH=gld${EMULATION_NAME}_finish |
| 530 | LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_create_output_section_statements |
| 531 | LDEMUL_NEW_VERS_PATTERN=gld${EMULATION_NAME}_new_vers_pattern |