1 # This shell script emits a C file. -*- C -*-
2 # Copyright 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
3 # Free Software Foundation, Inc.
5 # This file is part of the GNU Binutils.
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 3 of the License, or
10 # (at your option) any later version.
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.
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., 51 Franklin Street - Fifth Floor, Boston,
23 # This file is sourced from elf32.em, and defines extra powerpc64-elf
31 #include "elf64-ppc.h"
33 /* Fake input file for stubs. */
34 static lang_input_statement_type *stub_file;
35 static int stub_added = 0;
37 /* Whether we need to call ppc_layout_sections_again. */
38 static int need_laying_out = 0;
40 /* Maximum size of a group of input sections that can be handled by
41 one stub section. A value of +/-1 indicates the bfd back-end
42 should use a suitable default size. */
43 static bfd_signed_vma group_size = 1;
45 /* Whether to add ".foo" entries for each "foo" in a version script. */
46 static int dotsyms = 1;
48 /* Whether to run tls optimization. */
49 static int no_tls_opt = 0;
50 static int no_tls_get_addr_opt = 0;
52 /* Whether to run opd optimization. */
53 static int no_opd_opt = 0;
55 /* Whether to run toc optimization. */
56 static int no_toc_opt = 0;
58 /* Whether to allow multiple toc sections. */
59 static int no_multi_toc = 0;
61 /* Whether to sort input toc and got sections. */
62 static int no_toc_sort = 0;
64 /* Set if PLT call stubs should load r11. */
65 static int plt_static_chain = ${DEFAULT_PLT_STATIC_CHAIN-0};
67 /* Set if PLT call stubs need to be thread safe on power7+. */
68 static int plt_thread_safe = -1;
70 /* Set if individual PLT call stubs should be aligned. */
71 static int plt_stub_align = 0;
73 /* Whether to emit symbols for stubs. */
74 static int emit_stub_syms = -1;
76 static asection *toc_section = 0;
78 /* Whether to canonicalize .opd so that there are no overlapping
80 static int non_overlapping_opd = 0;
82 /* This is called before the input files are opened. We create a new
83 fake input file to hold the stub sections. */
86 ppc_create_output_section_statements (void)
88 if (!(bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour
89 && elf_object_id (link_info.output_bfd) == PPC64_ELF_DATA))
92 link_info.wrap_char = '.';
94 stub_file = lang_add_input_file ("linker stubs",
95 lang_input_file_is_fake_enum,
97 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
98 if (stub_file->the_bfd == NULL
99 || !bfd_set_arch_mach (stub_file->the_bfd,
100 bfd_get_arch (link_info.output_bfd),
101 bfd_get_mach (link_info.output_bfd)))
103 einfo ("%F%P: can not create BFD: %E\n");
107 stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
108 ldlang_add_file (stub_file);
109 ppc64_elf_init_stub_bfd (stub_file->the_bfd, &link_info);
112 /* Move the input section statement at *U which happens to be on LIST
113 to be just before *TO. */
116 move_input_section (lang_statement_list_type *list,
117 lang_statement_union_type **u,
118 lang_statement_union_type **to)
120 lang_statement_union_type *s = *u;
121 asection *i = s->input_section.section;
124 /* Snip the input section from the statement list. If it was the
125 last statement, fix the list tail pointer. */
129 /* Add it back in the new position. */
130 s->header.next = *to;
132 if (list->tail == to)
133 list->tail = &s->header.next;
135 /* Trim I off the bfd map_head/map_tail doubly linked lists. */
138 (p != NULL ? p : i->output_section)->map_head.s = n;
139 (n != NULL ? n : i->output_section)->map_tail.s = p;
141 /* Add I back on in its new position. */
142 if (s->header.next->header.type == lang_input_section_enum)
144 n = s->header.next->input_section.section;
149 /* If the next statement is not an input section statement then
150 TO must point at the previous input section statement
151 header.next field. */
152 lang_input_section_type *prev = (lang_input_section_type *)
153 ((char *) to - offsetof (lang_statement_union_type, header.next));
155 ASSERT (prev->header.type == lang_input_section_enum);
161 (p != NULL ? p : i->output_section)->map_head.s = i;
162 (n != NULL ? n : i->output_section)->map_tail.s = i;
165 /* Sort input section statements in the linker script tree rooted at
166 LIST so that those whose owning bfd happens to have a section
167 called .init or .fini are placed first. Place any TOC sections
168 referenced by small TOC relocs next, with TOC sections referenced
169 only by bigtoc relocs last. */
172 sort_toc_sections (lang_statement_list_type *list,
173 lang_statement_union_type **ini,
174 lang_statement_union_type **small)
176 lang_statement_union_type *s, **u;
180 while ((s = *u) != NULL)
182 switch (s->header.type)
184 case lang_wild_statement_enum:
185 sort_toc_sections (&s->wild_statement.children, ini, small);
188 case lang_group_statement_enum:
189 sort_toc_sections (&s->group_statement.children, ini, small);
192 case lang_input_section_enum:
193 i = s->input_section.section;
194 /* Leave the stub_file .got where it is. We put the .got
196 if (i->owner == stub_file->the_bfd)
198 if (bfd_get_section_by_name (i->owner, ".init") != NULL
199 || bfd_get_section_by_name (i->owner, ".fini") != NULL)
201 if (ini != NULL && *ini != s)
203 move_input_section (list, u, ini);
205 small = &s->header.next;
206 ini = &s->header.next;
210 small = &s->header.next;
211 ini = &s->header.next;
214 else if (ini == NULL)
217 if (ppc64_elf_has_small_toc_reloc (i))
219 if (small != NULL && *small != s)
221 move_input_section (list, u, small);
222 small = &s->header.next;
225 small = &s->header.next;
227 else if (small == NULL)
239 prelim_size_sections (void)
241 if (expld.phase != lang_mark_phase_enum)
243 expld.phase = lang_mark_phase_enum;
244 expld.dataseg.phase = exp_dataseg_none;
245 one_lang_size_sections_pass (NULL, FALSE);
246 /* We must not cache anything from the preliminary sizing. */
247 lang_reset_memory_regions ();
252 ppc_before_allocation (void)
254 if (stub_file != NULL)
257 && !ppc64_elf_edit_opd (&link_info, non_overlapping_opd))
258 einfo ("%X%P: can not edit %s: %E\n", "opd");
260 if (ppc64_elf_tls_setup (&link_info, no_tls_get_addr_opt, &no_multi_toc)
263 /* Size the sections. This is premature, but we want to know the
264 TLS segment layout so that certain optimizations can be done. */
265 prelim_size_sections ();
267 if (!ppc64_elf_tls_optimize (&link_info))
268 einfo ("%X%P: TLS problem %E\n");
272 && !link_info.relocatable)
274 prelim_size_sections ();
276 if (!ppc64_elf_edit_toc (&link_info))
277 einfo ("%X%P: can not edit %s: %E\n", "toc");
282 lang_output_section_statement_type *toc_os;
284 toc_os = lang_output_section_find (".got");
286 sort_toc_sections (&toc_os->children, NULL, NULL);
290 gld${EMULATION_NAME}_before_allocation ();
293 struct hook_stub_info
295 lang_statement_list_type add;
296 asection *input_section;
299 /* Traverse the linker tree to find the spot where the stub goes. */
302 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
304 lang_statement_union_type *l;
307 for (; (l = *lp) != NULL; lp = &l->header.next)
309 switch (l->header.type)
311 case lang_constructors_statement_enum:
312 ret = hook_in_stub (info, &constructor_list.head);
317 case lang_output_section_statement_enum:
318 ret = hook_in_stub (info,
319 &l->output_section_statement.children.head);
324 case lang_wild_statement_enum:
325 ret = hook_in_stub (info, &l->wild_statement.children.head);
330 case lang_group_statement_enum:
331 ret = hook_in_stub (info, &l->group_statement.children.head);
336 case lang_input_section_enum:
337 if (l->input_section.section == info->input_section)
339 /* We've found our section. Insert the stub immediately
340 before its associated input section. */
341 *lp = info->add.head;
342 *(info->add.tail) = l;
347 case lang_data_statement_enum:
348 case lang_reloc_statement_enum:
349 case lang_object_symbols_statement_enum:
350 case lang_output_statement_enum:
351 case lang_target_statement_enum:
352 case lang_input_statement_enum:
353 case lang_assignment_statement_enum:
354 case lang_padding_statement_enum:
355 case lang_address_statement_enum:
356 case lang_fill_statement_enum:
368 /* Call-back for ppc64_elf_size_stubs. */
370 /* Create a new stub section, and arrange for it to be linked
371 immediately before INPUT_SECTION. */
374 ppc_add_stub_section (const char *stub_sec_name, asection *input_section)
378 asection *output_section;
380 lang_output_section_statement_type *os;
381 struct hook_stub_info info;
383 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
384 | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
385 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
386 stub_sec_name, flags);
388 || !bfd_set_section_alignment (stub_file->the_bfd, stub_sec,
389 plt_stub_align > 5 ? plt_stub_align : 5))
392 output_section = input_section->output_section;
393 secname = bfd_get_section_name (output_section->owner, output_section);
394 os = lang_output_section_find (secname);
396 info.input_section = input_section;
397 lang_list_init (&info.add);
398 lang_add_section (&info.add, stub_sec, os);
400 if (info.add.head == NULL)
404 if (hook_in_stub (&info, &os->children.head))
408 einfo ("%X%P: can not make stub section: %E\n");
413 /* Another call-back for ppc64_elf_size_stubs. */
416 ppc_layout_sections_again (void)
418 /* If we have changed sizes of the stub sections, then we need
419 to recalculate all the section offsets. This may mean we need to
420 add even more stubs. */
421 gld${EMULATION_NAME}_map_segments (TRUE);
423 if (!link_info.relocatable)
424 _bfd_set_gp_value (link_info.output_bfd,
425 ppc64_elf_toc (link_info.output_bfd));
427 need_laying_out = -1;
432 build_toc_list (lang_statement_union_type *statement)
434 if (statement->header.type == lang_input_section_enum)
436 asection *i = statement->input_section.section;
438 if (!((lang_input_statement_type *) i->owner->usrdata)->just_syms_flag
439 && (i->flags & SEC_EXCLUDE) == 0
440 && i->output_section == toc_section)
442 if (!ppc64_elf_next_toc_section (&link_info, i))
443 einfo ("%X%P: linker script separates .got and .toc\n");
450 build_section_lists (lang_statement_union_type *statement)
452 if (statement->header.type == lang_input_section_enum)
454 asection *i = statement->input_section.section;
456 if (!((lang_input_statement_type *) i->owner->usrdata)->just_syms_flag
457 && (i->flags & SEC_EXCLUDE) == 0
458 && i->output_section != NULL
459 && i->output_section->owner == link_info.output_bfd)
461 if (!ppc64_elf_next_input_section (&link_info, i))
462 einfo ("%X%P: can not size stub section: %E\n");
468 /* Call the back-end function to set TOC base after we have placed all
471 gld${EMULATION_NAME}_after_allocation (void)
473 /* bfd_elf_discard_info just plays with data and debugging sections,
474 ie. doesn't affect code size, so we can delay resizing the
475 sections. It's likely we'll resize everything in the process of
477 if (bfd_elf_discard_info (link_info.output_bfd, &link_info))
480 /* If generating a relocatable output file, then we don't have any
482 if (stub_file != NULL && !link_info.relocatable)
484 int ret = ppc64_elf_setup_section_lists (&link_info,
485 &ppc_add_stub_section,
486 &ppc_layout_sections_again);
488 einfo ("%X%P: can not size stub section: %E\n");
491 ppc64_elf_start_multitoc_partition (&link_info);
495 toc_section = bfd_get_section_by_name (link_info.output_bfd,
497 if (toc_section != NULL)
498 lang_for_each_statement (build_toc_list);
501 if (ppc64_elf_layout_multitoc (&link_info)
503 && toc_section != NULL)
504 lang_for_each_statement (build_toc_list);
506 ppc64_elf_finish_multitoc_partition (&link_info);
508 lang_for_each_statement (build_section_lists);
510 if (!ppc64_elf_check_init_fini (&link_info))
511 einfo ("%P: .init/.fini fragments use differing TOC pointers\n");
513 /* Call into the BFD backend to do the real work. */
514 if (!ppc64_elf_size_stubs (&link_info, group_size,
515 plt_static_chain, plt_thread_safe,
517 einfo ("%X%P: can not size stub section: %E\n");
521 if (need_laying_out != -1)
523 gld${EMULATION_NAME}_map_segments (need_laying_out);
525 if (!link_info.relocatable)
526 _bfd_set_gp_value (link_info.output_bfd,
527 ppc64_elf_toc (link_info.output_bfd));
532 /* Final emulation specific call. */
535 gld${EMULATION_NAME}_finish (void)
537 /* e_entry on PowerPC64 points to the function descriptor for
538 _start. If _start is missing, default to the first function
539 descriptor in the .opd section. */
540 entry_section = ".opd";
545 char *line, *endline;
547 if (emit_stub_syms < 0)
549 if (!ppc64_elf_build_stubs (emit_stub_syms, &link_info,
550 config.stats ? &msg : NULL))
551 einfo ("%X%P: can not build stubs: %E\n");
554 for (line = msg; line != NULL; line = endline)
556 endline = strchr (line, '\n');
559 fprintf (stderr, "%s: %s\n", program_name, line);
566 ppc64_elf_restore_symbols (&link_info);
571 /* Add a pattern matching ".foo" for every "foo" in a version script.
573 The reason for doing this is that many shared library version
574 scripts export a selected set of functions or data symbols, forcing
579 . this; that; some; thing;
584 To make the above work for PowerPC64, we need to export ".this",
585 ".that" and so on, otherwise only the function descriptor syms are
586 exported. Lack of an exported function code sym may cause a
587 definition to be pulled in from a static library. */
589 static struct bfd_elf_version_expr *
590 gld${EMULATION_NAME}_new_vers_pattern (struct bfd_elf_version_expr *entry)
592 struct bfd_elf_version_expr *dot_entry;
597 || entry->pattern[0] == '.'
598 || (!entry->literal && entry->pattern[0] == '*'))
601 dot_entry = xmalloc (sizeof *dot_entry);
603 dot_entry->next = entry;
604 len = strlen (entry->pattern) + 2;
605 dot_pat = xmalloc (len);
607 memcpy (dot_pat + 1, entry->pattern, len - 1);
608 dot_entry->pattern = dot_pat;
609 dot_entry->script = 1;
614 /* Avoid processing the fake stub_file in vercheck, stat_needed and
615 check_needed routines. */
617 static void (*real_func) (lang_input_statement_type *);
619 static void ppc_for_each_input_file_wrapper (lang_input_statement_type *l)
626 ppc_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
629 lang_for_each_input_file (&ppc_for_each_input_file_wrapper);
632 #define lang_for_each_input_file ppc_lang_for_each_input_file
636 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
638 /* Special handling for embedded SPU executables. */
639 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
640 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
643 ppc64_recognized_file (lang_input_statement_type *entry)
645 if (embedded_spu_file (entry, "-m64"))
648 return gld${EMULATION_NAME}_load_symbols (entry);
651 LDEMUL_RECOGNIZED_FILE=ppc64_recognized_file
654 # Define some shell vars to insert bits of code into the standard elf
655 # parse_args and list_options functions.
657 PARSE_AND_LIST_PROLOGUE=${PARSE_AND_LIST_PROLOGUE}'
658 #define OPTION_STUBGROUP_SIZE 321
659 #define OPTION_PLT_STATIC_CHAIN (OPTION_STUBGROUP_SIZE + 1)
660 #define OPTION_NO_PLT_STATIC_CHAIN (OPTION_PLT_STATIC_CHAIN + 1)
661 #define OPTION_PLT_THREAD_SAFE (OPTION_NO_PLT_STATIC_CHAIN + 1)
662 #define OPTION_NO_PLT_THREAD_SAFE (OPTION_PLT_THREAD_SAFE + 1)
663 #define OPTION_PLT_ALIGN (OPTION_NO_PLT_THREAD_SAFE + 1)
664 #define OPTION_NO_PLT_ALIGN (OPTION_PLT_ALIGN + 1)
665 #define OPTION_STUBSYMS (OPTION_NO_PLT_ALIGN + 1)
666 #define OPTION_NO_STUBSYMS (OPTION_STUBSYMS + 1)
667 #define OPTION_DOTSYMS (OPTION_NO_STUBSYMS + 1)
668 #define OPTION_NO_DOTSYMS (OPTION_DOTSYMS + 1)
669 #define OPTION_NO_TLS_OPT (OPTION_NO_DOTSYMS + 1)
670 #define OPTION_NO_TLS_GET_ADDR_OPT (OPTION_NO_TLS_OPT + 1)
671 #define OPTION_NO_OPD_OPT (OPTION_NO_TLS_GET_ADDR_OPT + 1)
672 #define OPTION_NO_TOC_OPT (OPTION_NO_OPD_OPT + 1)
673 #define OPTION_NO_MULTI_TOC (OPTION_NO_TOC_OPT + 1)
674 #define OPTION_NO_TOC_SORT (OPTION_NO_MULTI_TOC + 1)
675 #define OPTION_NON_OVERLAPPING_OPD (OPTION_NO_TOC_SORT + 1)
678 PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}'
679 { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
680 { "plt-static-chain", no_argument, NULL, OPTION_PLT_STATIC_CHAIN },
681 { "no-plt-static-chain", no_argument, NULL, OPTION_NO_PLT_STATIC_CHAIN },
682 { "plt-thread-safe", no_argument, NULL, OPTION_PLT_THREAD_SAFE },
683 { "no-plt-thread-safe", no_argument, NULL, OPTION_NO_PLT_THREAD_SAFE },
684 { "plt-align", optional_argument, NULL, OPTION_PLT_ALIGN },
685 { "no-plt-align", no_argument, NULL, OPTION_NO_PLT_ALIGN },
686 { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
687 { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
688 { "dotsyms", no_argument, NULL, OPTION_DOTSYMS },
689 { "no-dotsyms", no_argument, NULL, OPTION_NO_DOTSYMS },
690 { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
691 { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
692 { "no-opd-optimize", no_argument, NULL, OPTION_NO_OPD_OPT },
693 { "no-toc-optimize", no_argument, NULL, OPTION_NO_TOC_OPT },
694 { "no-multi-toc", no_argument, NULL, OPTION_NO_MULTI_TOC },
695 { "no-toc-sort", no_argument, NULL, OPTION_NO_TOC_SORT },
696 { "non-overlapping-opd", no_argument, NULL, OPTION_NON_OVERLAPPING_OPD },
699 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'
701 --stub-group-size=N Maximum size of a group of input sections that\n\
702 can be handled by one stub section. A negative\n\
703 value locates all stubs before their branches\n\
704 (with a group size of -N), while a positive\n\
705 value allows two groups of input sections, one\n\
706 before, and one after each stub section.\n\
707 Values of +/-1 indicate the linker should\n\
708 choose suitable defaults.\n"
711 --plt-static-chain PLT call stubs should load r11.${DEFAULT_PLT_STATIC_CHAIN- (default)}\n"
714 --no-plt-static-chain PLT call stubs should not load r11.${DEFAULT_PLT_STATIC_CHAIN+ (default)}\n"
717 --plt-thread-safe PLT call stubs with load-load barrier.\n"
720 --no-plt-thread-safe PLT call stubs without barrier.\n"
723 --plt-align [=<align>] Align PLT call stubs to fit cache lines.\n"
726 --no-plt-align Dont'\''t align individual PLT call stubs.\n"
729 --emit-stub-syms Label linker stubs with a symbol.\n"
732 --no-emit-stub-syms Don'\''t label linker stubs with a symbol.\n"
735 --dotsyms For every version pattern \"foo\" in a version\n\
736 script, add \".foo\" so that function code\n\
737 symbols are treated the same as function\n\
738 descriptor symbols. Defaults to on.\n"
741 --no-dotsyms Don'\''t do anything special in version scripts.\n"
744 --no-tls-optimize Don'\''t try to optimize TLS accesses.\n"
747 --no-tls-get-addr-optimize Don'\''t use a special __tls_get_addr call.\n"
750 --no-opd-optimize Don'\''t optimize the OPD section.\n"
753 --no-toc-optimize Don'\''t optimize the TOC section.\n"
756 --no-multi-toc Disallow automatic multiple toc sections.\n"
759 --no-toc-sort Don'\''t sort TOC and GOT sections.\n"
762 --non-overlapping-opd Canonicalize .opd, so that there are no\n\
763 overlapping .opd entries.\n"
767 PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}'
768 case OPTION_STUBGROUP_SIZE:
771 group_size = bfd_scan_vma (optarg, &end, 0);
773 einfo (_("%P%F: invalid number `%s'\''\n"), optarg);
777 case OPTION_PLT_STATIC_CHAIN:
778 plt_static_chain = 1;
781 case OPTION_NO_PLT_STATIC_CHAIN:
782 plt_static_chain = 0;
785 case OPTION_PLT_THREAD_SAFE:
789 case OPTION_NO_PLT_THREAD_SAFE:
793 case OPTION_PLT_ALIGN:
797 unsigned long val = strtoul (optarg, &end, 0);
799 einfo (_("%P%F: invalid --plt-align `%s'\''\n"), optarg);
800 plt_stub_align = val;
806 case OPTION_NO_PLT_ALIGN:
810 case OPTION_STUBSYMS:
814 case OPTION_NO_STUBSYMS:
822 case OPTION_NO_DOTSYMS:
826 case OPTION_NO_TLS_OPT:
830 case OPTION_NO_TLS_GET_ADDR_OPT:
831 no_tls_get_addr_opt = 1;
834 case OPTION_NO_OPD_OPT:
838 case OPTION_NO_TOC_OPT:
842 case OPTION_NO_MULTI_TOC:
846 case OPTION_NO_TOC_SORT:
850 case OPTION_NON_OVERLAPPING_OPD:
851 non_overlapping_opd = 1;
855 # Put these extra ppc64elf routines in ld_${EMULATION_NAME}_emulation
857 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation
858 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
859 LDEMUL_FINISH=gld${EMULATION_NAME}_finish
860 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_create_output_section_statements
861 LDEMUL_NEW_VERS_PATTERN=gld${EMULATION_NAME}_new_vers_pattern