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"
34 /* Fake input file for stubs. */
35 static lang_input_statement_type *stub_file;
36 static int stub_added = 0;
38 /* Whether we need to call ppc_layout_sections_again. */
39 static int need_laying_out = 0;
41 /* Maximum size of a group of input sections that can be handled by
42 one stub section. A value of +/-1 indicates the bfd back-end
43 should use a suitable default size. */
44 static bfd_signed_vma group_size = 1;
46 /* Whether to add ".foo" entries for each "foo" in a version script. */
47 static int dotsyms = 1;
49 /* Whether to run tls optimization. */
50 static int no_tls_opt = 0;
51 static int no_tls_get_addr_opt = 0;
53 /* Whether to run opd optimization. */
54 static int no_opd_opt = 0;
56 /* Whether to run toc optimization. */
57 static int no_toc_opt = 0;
59 /* Whether to allow multiple toc sections. */
60 static int no_multi_toc = 0;
62 /* Whether to sort input toc and got sections. */
63 static int no_toc_sort = 0;
65 /* Set if PLT call stubs should load r11. */
66 static int plt_static_chain = ${DEFAULT_PLT_STATIC_CHAIN-0};
68 /* Set if PLT call stubs need to be thread safe on power7+. */
69 static int plt_thread_safe = -1;
71 /* Set if individual PLT call stubs should be aligned. */
72 static int plt_stub_align = 0;
74 /* Whether to emit symbols for stubs. */
75 static int emit_stub_syms = -1;
77 static asection *toc_section = 0;
79 /* Whether to canonicalize .opd so that there are no overlapping
81 static int non_overlapping_opd = 0;
83 /* This is called before the input files are opened. We create a new
84 fake input file to hold the stub sections. */
87 ppc_create_output_section_statements (void)
89 if (!(bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour
90 && elf_object_id (link_info.output_bfd) == PPC64_ELF_DATA))
93 link_info.wrap_char = '.';
95 stub_file = lang_add_input_file ("linker stubs",
96 lang_input_file_is_fake_enum,
98 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
99 if (stub_file->the_bfd == NULL
100 || !bfd_set_arch_mach (stub_file->the_bfd,
101 bfd_get_arch (link_info.output_bfd),
102 bfd_get_mach (link_info.output_bfd)))
104 einfo ("%F%P: can not create BFD: %E\n");
108 stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
109 ldlang_add_file (stub_file);
110 ppc64_elf_init_stub_bfd (stub_file->the_bfd, &link_info);
113 /* Move the input section statement at *U which happens to be on LIST
114 to be just before *TO. */
117 move_input_section (lang_statement_list_type *list,
118 lang_statement_union_type **u,
119 lang_statement_union_type **to)
121 lang_statement_union_type *s = *u;
122 asection *i = s->input_section.section;
125 /* Snip the input section from the statement list. If it was the
126 last statement, fix the list tail pointer. */
130 /* Add it back in the new position. */
131 s->header.next = *to;
133 if (list->tail == to)
134 list->tail = &s->header.next;
136 /* Trim I off the bfd map_head/map_tail doubly linked lists. */
139 (p != NULL ? p : i->output_section)->map_head.s = n;
140 (n != NULL ? n : i->output_section)->map_tail.s = p;
142 /* Add I back on in its new position. */
143 if (s->header.next->header.type == lang_input_section_enum)
145 n = s->header.next->input_section.section;
150 /* If the next statement is not an input section statement then
151 TO must point at the previous input section statement
152 header.next field. */
153 lang_input_section_type *prev = (lang_input_section_type *)
154 ((char *) to - offsetof (lang_statement_union_type, header.next));
156 ASSERT (prev->header.type == lang_input_section_enum);
162 (p != NULL ? p : i->output_section)->map_head.s = i;
163 (n != NULL ? n : i->output_section)->map_tail.s = i;
166 /* Sort input section statements in the linker script tree rooted at
167 LIST so that those whose owning bfd happens to have a section
168 called .init or .fini are placed first. Place any TOC sections
169 referenced by small TOC relocs next, with TOC sections referenced
170 only by bigtoc relocs last. */
173 sort_toc_sections (lang_statement_list_type *list,
174 lang_statement_union_type **ini,
175 lang_statement_union_type **small)
177 lang_statement_union_type *s, **u;
181 while ((s = *u) != NULL)
183 switch (s->header.type)
185 case lang_wild_statement_enum:
186 sort_toc_sections (&s->wild_statement.children, ini, small);
189 case lang_group_statement_enum:
190 sort_toc_sections (&s->group_statement.children, ini, small);
193 case lang_input_section_enum:
194 i = s->input_section.section;
195 /* Leave the stub_file .got where it is. We put the .got
197 if (i->owner == stub_file->the_bfd)
199 if (bfd_get_section_by_name (i->owner, ".init") != NULL
200 || bfd_get_section_by_name (i->owner, ".fini") != NULL)
202 if (ini != NULL && *ini != s)
204 move_input_section (list, u, ini);
206 small = &s->header.next;
207 ini = &s->header.next;
211 small = &s->header.next;
212 ini = &s->header.next;
215 else if (ini == NULL)
218 if (ppc64_elf_has_small_toc_reloc (i))
220 if (small != NULL && *small != s)
222 move_input_section (list, u, small);
223 small = &s->header.next;
226 small = &s->header.next;
228 else if (small == NULL)
240 prelim_size_sections (void)
242 if (expld.phase != lang_mark_phase_enum)
244 expld.phase = lang_mark_phase_enum;
245 expld.dataseg.phase = exp_dataseg_none;
246 one_lang_size_sections_pass (NULL, FALSE);
247 /* We must not cache anything from the preliminary sizing. */
248 lang_reset_memory_regions ();
253 ppc_before_allocation (void)
255 if (stub_file != NULL)
258 && !ppc64_elf_edit_opd (&link_info, non_overlapping_opd))
259 einfo ("%X%P: can not edit %s: %E\n", "opd");
261 if (ppc64_elf_tls_setup (&link_info, no_tls_get_addr_opt, &no_multi_toc)
264 /* Size the sections. This is premature, but we want to know the
265 TLS segment layout so that certain optimizations can be done. */
266 prelim_size_sections ();
268 if (!ppc64_elf_tls_optimize (&link_info))
269 einfo ("%X%P: TLS problem %E\n");
273 && !link_info.relocatable)
275 prelim_size_sections ();
277 if (!ppc64_elf_edit_toc (&link_info))
278 einfo ("%X%P: can not edit %s: %E\n", "toc");
283 lang_output_section_statement_type *toc_os;
285 toc_os = lang_output_section_find (".got");
287 sort_toc_sections (&toc_os->children, NULL, NULL);
291 gld${EMULATION_NAME}_before_allocation ();
294 struct hook_stub_info
296 lang_statement_list_type add;
297 asection *input_section;
300 /* Traverse the linker tree to find the spot where the stub goes. */
303 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
305 lang_statement_union_type *l;
308 for (; (l = *lp) != NULL; lp = &l->header.next)
310 switch (l->header.type)
312 case lang_constructors_statement_enum:
313 ret = hook_in_stub (info, &constructor_list.head);
318 case lang_output_section_statement_enum:
319 ret = hook_in_stub (info,
320 &l->output_section_statement.children.head);
325 case lang_wild_statement_enum:
326 ret = hook_in_stub (info, &l->wild_statement.children.head);
331 case lang_group_statement_enum:
332 ret = hook_in_stub (info, &l->group_statement.children.head);
337 case lang_input_section_enum:
338 if (l->input_section.section == info->input_section)
340 /* We've found our section. Insert the stub immediately
341 before its associated input section. */
342 *lp = info->add.head;
343 *(info->add.tail) = l;
348 case lang_data_statement_enum:
349 case lang_reloc_statement_enum:
350 case lang_object_symbols_statement_enum:
351 case lang_output_statement_enum:
352 case lang_target_statement_enum:
353 case lang_input_statement_enum:
354 case lang_assignment_statement_enum:
355 case lang_padding_statement_enum:
356 case lang_address_statement_enum:
357 case lang_fill_statement_enum:
369 /* Call-back for ppc64_elf_size_stubs. */
371 /* Create a new stub section, and arrange for it to be linked
372 immediately before INPUT_SECTION. */
375 ppc_add_stub_section (const char *stub_sec_name, asection *input_section)
379 asection *output_section;
381 lang_output_section_statement_type *os;
382 struct hook_stub_info info;
384 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
385 | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
386 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
387 stub_sec_name, flags);
389 || !bfd_set_section_alignment (stub_file->the_bfd, stub_sec,
390 plt_stub_align > 5 ? plt_stub_align : 5))
393 output_section = input_section->output_section;
394 secname = bfd_get_section_name (output_section->owner, output_section);
395 os = lang_output_section_find (secname);
397 info.input_section = input_section;
398 lang_list_init (&info.add);
399 lang_add_section (&info.add, stub_sec, NULL, os);
401 if (info.add.head == NULL)
405 if (hook_in_stub (&info, &os->children.head))
409 einfo ("%X%P: can not make stub section: %E\n");
414 /* Another call-back for ppc64_elf_size_stubs. */
417 ppc_layout_sections_again (void)
419 /* If we have changed sizes of the stub sections, then we need
420 to recalculate all the section offsets. This may mean we need to
421 add even more stubs. */
422 gld${EMULATION_NAME}_map_segments (TRUE);
424 if (!link_info.relocatable)
425 _bfd_set_gp_value (link_info.output_bfd,
426 ppc64_elf_toc (link_info.output_bfd));
428 need_laying_out = -1;
433 build_toc_list (lang_statement_union_type *statement)
435 if (statement->header.type == lang_input_section_enum)
437 asection *i = statement->input_section.section;
439 if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
440 && (i->flags & SEC_EXCLUDE) == 0
441 && i->output_section == toc_section)
443 if (!ppc64_elf_next_toc_section (&link_info, i))
444 einfo ("%X%P: linker script separates .got and .toc\n");
451 build_section_lists (lang_statement_union_type *statement)
453 if (statement->header.type == lang_input_section_enum)
455 asection *i = statement->input_section.section;
457 if (!((lang_input_statement_type *) i->owner->usrdata)->flags.just_syms
458 && (i->flags & SEC_EXCLUDE) == 0
459 && i->output_section != NULL
460 && i->output_section->owner == link_info.output_bfd)
462 if (!ppc64_elf_next_input_section (&link_info, i))
463 einfo ("%X%P: can not size stub section: %E\n");
469 /* Call the back-end function to set TOC base after we have placed all
472 gld${EMULATION_NAME}_after_allocation (void)
474 /* bfd_elf_discard_info just plays with data and debugging sections,
475 ie. doesn't affect code size, so we can delay resizing the
476 sections. It's likely we'll resize everything in the process of
478 if (bfd_elf_discard_info (link_info.output_bfd, &link_info))
481 /* If generating a relocatable output file, then we don't have any
483 if (stub_file != NULL && !link_info.relocatable)
485 int ret = ppc64_elf_setup_section_lists (&link_info,
486 &ppc_add_stub_section,
487 &ppc_layout_sections_again);
489 einfo ("%X%P: can not size stub section: %E\n");
492 ppc64_elf_start_multitoc_partition (&link_info);
496 toc_section = bfd_get_section_by_name (link_info.output_bfd,
498 if (toc_section != NULL)
499 lang_for_each_statement (build_toc_list);
502 if (ppc64_elf_layout_multitoc (&link_info)
504 && toc_section != NULL)
505 lang_for_each_statement (build_toc_list);
507 ppc64_elf_finish_multitoc_partition (&link_info);
509 lang_for_each_statement (build_section_lists);
511 if (!ppc64_elf_check_init_fini (&link_info))
512 einfo ("%P: .init/.fini fragments use differing TOC pointers\n");
514 /* Call into the BFD backend to do the real work. */
515 if (!ppc64_elf_size_stubs (&link_info, group_size,
516 plt_static_chain, plt_thread_safe,
518 einfo ("%X%P: can not size stub section: %E\n");
522 if (need_laying_out != -1)
524 gld${EMULATION_NAME}_map_segments (need_laying_out);
526 if (!link_info.relocatable)
527 _bfd_set_gp_value (link_info.output_bfd,
528 ppc64_elf_toc (link_info.output_bfd));
533 /* Final emulation specific call. */
536 gld${EMULATION_NAME}_finish (void)
538 /* e_entry on PowerPC64 points to the function descriptor for
539 _start. If _start is missing, default to the first function
540 descriptor in the .opd section. */
541 entry_section = ".opd";
546 char *line, *endline;
548 if (emit_stub_syms < 0)
550 if (!ppc64_elf_build_stubs (emit_stub_syms, &link_info,
551 config.stats ? &msg : NULL))
552 einfo ("%X%P: can not build stubs: %E\n");
555 for (line = msg; line != NULL; line = endline)
557 endline = strchr (line, '\n');
560 fprintf (stderr, "%s: %s\n", program_name, line);
567 ppc64_elf_restore_symbols (&link_info);
572 /* Add a pattern matching ".foo" for every "foo" in a version script.
574 The reason for doing this is that many shared library version
575 scripts export a selected set of functions or data symbols, forcing
580 . this; that; some; thing;
585 To make the above work for PowerPC64, we need to export ".this",
586 ".that" and so on, otherwise only the function descriptor syms are
587 exported. Lack of an exported function code sym may cause a
588 definition to be pulled in from a static library. */
590 static struct bfd_elf_version_expr *
591 gld${EMULATION_NAME}_new_vers_pattern (struct bfd_elf_version_expr *entry)
593 struct bfd_elf_version_expr *dot_entry;
598 || entry->pattern[0] == '.'
599 || (!entry->literal && entry->pattern[0] == '*'))
602 dot_entry = xmalloc (sizeof *dot_entry);
604 dot_entry->next = entry;
605 len = strlen (entry->pattern) + 2;
606 dot_pat = xmalloc (len);
608 memcpy (dot_pat + 1, entry->pattern, len - 1);
609 dot_entry->pattern = dot_pat;
610 dot_entry->script = 1;
615 /* Avoid processing the fake stub_file in vercheck, stat_needed and
616 check_needed routines. */
618 static void (*real_func) (lang_input_statement_type *);
620 static void ppc_for_each_input_file_wrapper (lang_input_statement_type *l)
627 ppc_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
630 lang_for_each_input_file (&ppc_for_each_input_file_wrapper);
633 #define lang_for_each_input_file ppc_lang_for_each_input_file
637 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
639 /* Special handling for embedded SPU executables. */
640 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
641 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
644 ppc64_recognized_file (lang_input_statement_type *entry)
646 if (embedded_spu_file (entry, "-m64"))
649 return gld${EMULATION_NAME}_load_symbols (entry);
652 LDEMUL_RECOGNIZED_FILE=ppc64_recognized_file
655 # Define some shell vars to insert bits of code into the standard elf
656 # parse_args and list_options functions.
658 PARSE_AND_LIST_PROLOGUE=${PARSE_AND_LIST_PROLOGUE}'
659 #define OPTION_STUBGROUP_SIZE 321
660 #define OPTION_PLT_STATIC_CHAIN (OPTION_STUBGROUP_SIZE + 1)
661 #define OPTION_NO_PLT_STATIC_CHAIN (OPTION_PLT_STATIC_CHAIN + 1)
662 #define OPTION_PLT_THREAD_SAFE (OPTION_NO_PLT_STATIC_CHAIN + 1)
663 #define OPTION_NO_PLT_THREAD_SAFE (OPTION_PLT_THREAD_SAFE + 1)
664 #define OPTION_PLT_ALIGN (OPTION_NO_PLT_THREAD_SAFE + 1)
665 #define OPTION_NO_PLT_ALIGN (OPTION_PLT_ALIGN + 1)
666 #define OPTION_STUBSYMS (OPTION_NO_PLT_ALIGN + 1)
667 #define OPTION_NO_STUBSYMS (OPTION_STUBSYMS + 1)
668 #define OPTION_DOTSYMS (OPTION_NO_STUBSYMS + 1)
669 #define OPTION_NO_DOTSYMS (OPTION_DOTSYMS + 1)
670 #define OPTION_NO_TLS_OPT (OPTION_NO_DOTSYMS + 1)
671 #define OPTION_NO_TLS_GET_ADDR_OPT (OPTION_NO_TLS_OPT + 1)
672 #define OPTION_NO_OPD_OPT (OPTION_NO_TLS_GET_ADDR_OPT + 1)
673 #define OPTION_NO_TOC_OPT (OPTION_NO_OPD_OPT + 1)
674 #define OPTION_NO_MULTI_TOC (OPTION_NO_TOC_OPT + 1)
675 #define OPTION_NO_TOC_SORT (OPTION_NO_MULTI_TOC + 1)
676 #define OPTION_NON_OVERLAPPING_OPD (OPTION_NO_TOC_SORT + 1)
679 PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}'
680 { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
681 { "plt-static-chain", no_argument, NULL, OPTION_PLT_STATIC_CHAIN },
682 { "no-plt-static-chain", no_argument, NULL, OPTION_NO_PLT_STATIC_CHAIN },
683 { "plt-thread-safe", no_argument, NULL, OPTION_PLT_THREAD_SAFE },
684 { "no-plt-thread-safe", no_argument, NULL, OPTION_NO_PLT_THREAD_SAFE },
685 { "plt-align", optional_argument, NULL, OPTION_PLT_ALIGN },
686 { "no-plt-align", no_argument, NULL, OPTION_NO_PLT_ALIGN },
687 { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
688 { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
689 { "dotsyms", no_argument, NULL, OPTION_DOTSYMS },
690 { "no-dotsyms", no_argument, NULL, OPTION_NO_DOTSYMS },
691 { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
692 { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
693 { "no-opd-optimize", no_argument, NULL, OPTION_NO_OPD_OPT },
694 { "no-toc-optimize", no_argument, NULL, OPTION_NO_TOC_OPT },
695 { "no-multi-toc", no_argument, NULL, OPTION_NO_MULTI_TOC },
696 { "no-toc-sort", no_argument, NULL, OPTION_NO_TOC_SORT },
697 { "non-overlapping-opd", no_argument, NULL, OPTION_NON_OVERLAPPING_OPD },
700 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'
702 --stub-group-size=N Maximum size of a group of input sections that\n\
703 can be handled by one stub section. A negative\n\
704 value locates all stubs before their branches\n\
705 (with a group size of -N), while a positive\n\
706 value allows two groups of input sections, one\n\
707 before, and one after each stub section.\n\
708 Values of +/-1 indicate the linker should\n\
709 choose suitable defaults.\n"
712 --plt-static-chain PLT call stubs should load r11.${DEFAULT_PLT_STATIC_CHAIN- (default)}\n"
715 --no-plt-static-chain PLT call stubs should not load r11.${DEFAULT_PLT_STATIC_CHAIN+ (default)}\n"
718 --plt-thread-safe PLT call stubs with load-load barrier.\n"
721 --no-plt-thread-safe PLT call stubs without barrier.\n"
724 --plt-align [=<align>] Align PLT call stubs to fit cache lines.\n"
727 --no-plt-align Dont'\''t align individual PLT call stubs.\n"
730 --emit-stub-syms Label linker stubs with a symbol.\n"
733 --no-emit-stub-syms Don'\''t label linker stubs with a symbol.\n"
736 --dotsyms For every version pattern \"foo\" in a version\n\
737 script, add \".foo\" so that function code\n\
738 symbols are treated the same as function\n\
739 descriptor symbols. Defaults to on.\n"
742 --no-dotsyms Don'\''t do anything special in version scripts.\n"
745 --no-tls-optimize Don'\''t try to optimize TLS accesses.\n"
748 --no-tls-get-addr-optimize Don'\''t use a special __tls_get_addr call.\n"
751 --no-opd-optimize Don'\''t optimize the OPD section.\n"
754 --no-toc-optimize Don'\''t optimize the TOC section.\n"
757 --no-multi-toc Disallow automatic multiple toc sections.\n"
760 --no-toc-sort Don'\''t sort TOC and GOT sections.\n"
763 --non-overlapping-opd Canonicalize .opd, so that there are no\n\
764 overlapping .opd entries.\n"
768 PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}'
769 case OPTION_STUBGROUP_SIZE:
772 group_size = bfd_scan_vma (optarg, &end, 0);
774 einfo (_("%P%F: invalid number `%s'\''\n"), optarg);
778 case OPTION_PLT_STATIC_CHAIN:
779 plt_static_chain = 1;
782 case OPTION_NO_PLT_STATIC_CHAIN:
783 plt_static_chain = 0;
786 case OPTION_PLT_THREAD_SAFE:
790 case OPTION_NO_PLT_THREAD_SAFE:
794 case OPTION_PLT_ALIGN:
798 unsigned long val = strtoul (optarg, &end, 0);
800 einfo (_("%P%F: invalid --plt-align `%s'\''\n"), optarg);
801 plt_stub_align = val;
807 case OPTION_NO_PLT_ALIGN:
811 case OPTION_STUBSYMS:
815 case OPTION_NO_STUBSYMS:
823 case OPTION_NO_DOTSYMS:
827 case OPTION_NO_TLS_OPT:
831 case OPTION_NO_TLS_GET_ADDR_OPT:
832 no_tls_get_addr_opt = 1;
835 case OPTION_NO_OPD_OPT:
839 case OPTION_NO_TOC_OPT:
843 case OPTION_NO_MULTI_TOC:
847 case OPTION_NO_TOC_SORT:
851 case OPTION_NON_OVERLAPPING_OPD:
852 non_overlapping_opd = 1;
855 case OPTION_TRADITIONAL_FORMAT:
857 no_tls_get_addr_opt = 1;
862 plt_static_chain = 1;
866 # Put these extra ppc64elf routines in ld_${EMULATION_NAME}_emulation
868 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation
869 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
870 LDEMUL_FINISH=gld${EMULATION_NAME}_finish
871 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_create_output_section_statements
872 LDEMUL_NEW_VERS_PATTERN=gld${EMULATION_NAME}_new_vers_pattern