1 # This shell script emits a C file. -*- C -*-
2 # Copyright 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
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 /* Whether to emit symbols for stubs. */
65 static int emit_stub_syms = -1;
67 static asection *toc_section = 0;
69 /* Whether to canonicalize .opd so that there are no overlapping
71 static int non_overlapping_opd = 0;
73 /* This is called before the input files are opened. We create a new
74 fake input file to hold the stub sections. */
77 ppc_create_output_section_statements (void)
79 if (!(bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour
80 && elf_object_id (link_info.output_bfd) == PPC64_ELF_DATA))
83 link_info.wrap_char = '.';
85 stub_file = lang_add_input_file ("linker stubs",
86 lang_input_file_is_fake_enum,
88 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
89 if (stub_file->the_bfd == NULL
90 || !bfd_set_arch_mach (stub_file->the_bfd,
91 bfd_get_arch (link_info.output_bfd),
92 bfd_get_mach (link_info.output_bfd)))
94 einfo ("%F%P: can not create BFD %E\n");
98 stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
99 ldlang_add_file (stub_file);
100 ppc64_elf_init_stub_bfd (stub_file->the_bfd, &link_info);
103 /* Move the input section statement at *U which happens to be on LIST
104 to be just before *TO. */
107 move_input_section (lang_statement_list_type *list,
108 lang_statement_union_type **u,
109 lang_statement_union_type **to)
111 lang_statement_union_type *s = *u;
112 asection *i = s->input_section.section;
115 /* Snip the input section from the statement list. If it was the
116 last statement, fix the list tail pointer. */
120 /* Add it back in the new position. */
121 s->header.next = *to;
123 if (list->tail == to)
124 list->tail = &s->header.next;
126 /* Trim I off the bfd map_head/map_tail doubly linked lists. */
129 (p != NULL ? p : i->output_section)->map_head.s = n;
130 (n != NULL ? n : i->output_section)->map_tail.s = p;
132 /* Add I back on in its new position. */
133 if (s->header.next->header.type == lang_input_section_enum)
135 n = s->header.next->input_section.section;
140 /* If the next statement is not an input section statement then
141 TO must point at the previous input section statement
142 header.next field. */
143 lang_input_section_type *prev = (lang_input_section_type *)
144 ((char *) to - offsetof (lang_statement_union_type, header.next));
146 ASSERT (prev->header.type == lang_input_section_enum);
152 (p != NULL ? p : i->output_section)->map_head.s = i;
153 (n != NULL ? n : i->output_section)->map_tail.s = i;
156 /* Sort input section statements in the linker script tree rooted at
157 LIST so that those whose owning bfd happens to have a section
158 called .init or .fini are placed first. Place any TOC sections
159 referenced by small TOC relocs next, with TOC sections referenced
160 only by bigtoc relocs last. */
163 sort_toc_sections (lang_statement_list_type *list,
164 lang_statement_union_type **ini,
165 lang_statement_union_type **small)
167 lang_statement_union_type *s, **u;
171 while ((s = *u) != NULL)
173 switch (s->header.type)
175 case lang_wild_statement_enum:
176 sort_toc_sections (&s->wild_statement.children, ini, small);
179 case lang_group_statement_enum:
180 sort_toc_sections (&s->group_statement.children, ini, small);
183 case lang_input_section_enum:
184 i = s->input_section.section;
185 /* Leave the stub_file .got where it is. We put the .got
187 if (i->owner == stub_file->the_bfd)
189 if (bfd_get_section_by_name (i->owner, ".init") != NULL
190 || bfd_get_section_by_name (i->owner, ".fini") != NULL)
192 if (ini != NULL && *ini != s)
194 move_input_section (list, u, ini);
196 small = &s->header.next;
197 ini = &s->header.next;
201 small = &s->header.next;
202 ini = &s->header.next;
205 else if (ini == NULL)
208 if (ppc64_elf_has_small_toc_reloc (i))
210 if (small != NULL && *small != s)
212 move_input_section (list, u, small);
213 small = &s->header.next;
216 small = &s->header.next;
218 else if (small == NULL)
230 ppc_before_allocation (void)
232 if (stub_file != NULL)
235 && !ppc64_elf_edit_opd (&link_info, non_overlapping_opd))
236 einfo ("%X%P: can not edit %s %E\n", "opd");
238 if (ppc64_elf_tls_setup (&link_info, no_tls_get_addr_opt, &no_multi_toc)
241 /* Size the sections. This is premature, but we want to know the
242 TLS segment layout so that certain optimizations can be done. */
243 expld.phase = lang_mark_phase_enum;
244 expld.dataseg.phase = exp_dataseg_none;
245 one_lang_size_sections_pass (NULL, TRUE);
247 if (!ppc64_elf_tls_optimize (&link_info))
248 einfo ("%X%P: TLS problem %E\n");
250 /* We must not cache anything from the preliminary sizing. */
251 lang_reset_memory_regions ();
255 && !link_info.relocatable
256 && !ppc64_elf_edit_toc (&link_info))
257 einfo ("%X%P: can not edit %s %E\n", "toc");
261 lang_output_section_statement_type *toc_os;
263 toc_os = lang_output_section_find (".got");
265 sort_toc_sections (&toc_os->children, NULL, NULL);
269 gld${EMULATION_NAME}_before_allocation ();
272 struct hook_stub_info
274 lang_statement_list_type add;
275 asection *input_section;
278 /* Traverse the linker tree to find the spot where the stub goes. */
281 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
283 lang_statement_union_type *l;
286 for (; (l = *lp) != NULL; lp = &l->header.next)
288 switch (l->header.type)
290 case lang_constructors_statement_enum:
291 ret = hook_in_stub (info, &constructor_list.head);
296 case lang_output_section_statement_enum:
297 ret = hook_in_stub (info,
298 &l->output_section_statement.children.head);
303 case lang_wild_statement_enum:
304 ret = hook_in_stub (info, &l->wild_statement.children.head);
309 case lang_group_statement_enum:
310 ret = hook_in_stub (info, &l->group_statement.children.head);
315 case lang_input_section_enum:
316 if (l->input_section.section == info->input_section)
318 /* We've found our section. Insert the stub immediately
319 before its associated input section. */
320 *lp = info->add.head;
321 *(info->add.tail) = l;
326 case lang_data_statement_enum:
327 case lang_reloc_statement_enum:
328 case lang_object_symbols_statement_enum:
329 case lang_output_statement_enum:
330 case lang_target_statement_enum:
331 case lang_input_statement_enum:
332 case lang_assignment_statement_enum:
333 case lang_padding_statement_enum:
334 case lang_address_statement_enum:
335 case lang_fill_statement_enum:
347 /* Call-back for ppc64_elf_size_stubs. */
349 /* Create a new stub section, and arrange for it to be linked
350 immediately before INPUT_SECTION. */
353 ppc_add_stub_section (const char *stub_sec_name, asection *input_section)
357 asection *output_section;
359 lang_output_section_statement_type *os;
360 struct hook_stub_info info;
362 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
363 | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
364 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
365 stub_sec_name, flags);
366 if (stub_sec == NULL)
369 output_section = input_section->output_section;
370 secname = bfd_get_section_name (output_section->owner, output_section);
371 os = lang_output_section_find (secname);
373 info.input_section = input_section;
374 lang_list_init (&info.add);
375 lang_add_section (&info.add, stub_sec, os);
377 if (info.add.head == NULL)
381 if (hook_in_stub (&info, &os->children.head))
385 einfo ("%X%P: can not make stub section: %E\n");
390 /* Another call-back for ppc64_elf_size_stubs. */
393 ppc_layout_sections_again (void)
395 /* If we have changed sizes of the stub sections, then we need
396 to recalculate all the section offsets. This may mean we need to
397 add even more stubs. */
398 gld${EMULATION_NAME}_map_segments (TRUE);
400 if (!link_info.relocatable)
401 _bfd_set_gp_value (link_info.output_bfd,
402 ppc64_elf_toc (link_info.output_bfd));
404 need_laying_out = -1;
409 build_toc_list (lang_statement_union_type *statement)
411 if (statement->header.type == lang_input_section_enum)
413 asection *i = statement->input_section.section;
415 if (!((lang_input_statement_type *) i->owner->usrdata)->just_syms_flag
416 && (i->flags & SEC_EXCLUDE) == 0
417 && i->output_section == toc_section)
419 if (!ppc64_elf_next_toc_section (&link_info, i))
420 einfo ("%X%P: linker script separates .got and .toc\n");
427 build_section_lists (lang_statement_union_type *statement)
429 if (statement->header.type == lang_input_section_enum)
431 asection *i = statement->input_section.section;
433 if (!((lang_input_statement_type *) i->owner->usrdata)->just_syms_flag
434 && (i->flags & SEC_EXCLUDE) == 0
435 && i->output_section != NULL
436 && i->output_section->owner == link_info.output_bfd)
438 if (!ppc64_elf_next_input_section (&link_info, i))
439 einfo ("%X%P: can not size stub section: %E\n");
445 /* Call the back-end function to set TOC base after we have placed all
448 gld${EMULATION_NAME}_after_allocation (void)
450 /* bfd_elf_discard_info just plays with data and debugging sections,
451 ie. doesn't affect code size, so we can delay resizing the
452 sections. It's likely we'll resize everything in the process of
454 if (bfd_elf_discard_info (link_info.output_bfd, &link_info))
457 /* If generating a relocatable output file, then we don't have any
459 if (stub_file != NULL && !link_info.relocatable)
461 int ret = ppc64_elf_setup_section_lists (&link_info,
462 &ppc_add_stub_section,
463 &ppc_layout_sections_again);
465 einfo ("%X%P: can not size stub section: %E\n");
468 ppc64_elf_start_multitoc_partition (&link_info);
472 toc_section = bfd_get_section_by_name (link_info.output_bfd,
474 if (toc_section != NULL)
475 lang_for_each_statement (build_toc_list);
478 if (ppc64_elf_layout_multitoc (&link_info)
480 && toc_section != NULL)
481 lang_for_each_statement (build_toc_list);
483 ppc64_elf_finish_multitoc_partition (&link_info);
485 lang_for_each_statement (build_section_lists);
487 if (!ppc64_elf_check_init_fini (&link_info))
488 einfo ("%P: .init/.fini fragments use differing TOC pointers\n");
490 /* Call into the BFD backend to do the real work. */
491 if (!ppc64_elf_size_stubs (&link_info, group_size))
492 einfo ("%X%P: can not size stub section: %E\n");
496 if (need_laying_out != -1)
498 gld${EMULATION_NAME}_map_segments (need_laying_out);
500 if (!link_info.relocatable)
501 _bfd_set_gp_value (link_info.output_bfd,
502 ppc64_elf_toc (link_info.output_bfd));
507 /* Final emulation specific call. */
510 gld${EMULATION_NAME}_finish (void)
512 /* e_entry on PowerPC64 points to the function descriptor for
513 _start. If _start is missing, default to the first function
514 descriptor in the .opd section. */
515 entry_section = ".opd";
517 if (link_info.relocatable)
519 asection *toc = bfd_get_section_by_name (link_info.output_bfd, ".toc");
521 && bfd_section_size (link_info.output_bfd, toc) > 0x10000)
522 einfo ("%X%P: TOC section size exceeds 64k\n");
528 char *line, *endline;
530 if (emit_stub_syms < 0)
532 if (!ppc64_elf_build_stubs (emit_stub_syms, &link_info,
533 config.stats ? &msg : NULL))
534 einfo ("%X%P: can not build stubs: %E\n");
536 for (line = msg; line != NULL; line = endline)
538 endline = strchr (line, '\n');
541 fprintf (stderr, "%s: %s\n", program_name, line);
547 ppc64_elf_restore_symbols (&link_info);
552 /* Add a pattern matching ".foo" for every "foo" in a version script.
554 The reason for doing this is that many shared library version
555 scripts export a selected set of functions or data symbols, forcing
560 . this; that; some; thing;
565 To make the above work for PowerPC64, we need to export ".this",
566 ".that" and so on, otherwise only the function descriptor syms are
567 exported. Lack of an exported function code sym may cause a
568 definition to be pulled in from a static library. */
570 static struct bfd_elf_version_expr *
571 gld${EMULATION_NAME}_new_vers_pattern (struct bfd_elf_version_expr *entry)
573 struct bfd_elf_version_expr *dot_entry;
578 || entry->pattern[0] == '.'
579 || (!entry->literal && entry->pattern[0] == '*'))
582 dot_entry = xmalloc (sizeof *dot_entry);
584 dot_entry->next = entry;
585 len = strlen (entry->pattern) + 2;
586 dot_pat = xmalloc (len);
588 memcpy (dot_pat + 1, entry->pattern, len - 1);
589 dot_entry->pattern = dot_pat;
594 /* Avoid processing the fake stub_file in vercheck, stat_needed and
595 check_needed routines. */
597 static void (*real_func) (lang_input_statement_type *);
599 static void ppc_for_each_input_file_wrapper (lang_input_statement_type *l)
606 ppc_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
609 lang_for_each_input_file (&ppc_for_each_input_file_wrapper);
612 #define lang_for_each_input_file ppc_lang_for_each_input_file
616 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
618 /* Special handling for embedded SPU executables. */
619 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
620 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
623 ppc64_recognized_file (lang_input_statement_type *entry)
625 if (embedded_spu_file (entry, "-m64"))
628 return gld${EMULATION_NAME}_load_symbols (entry);
631 LDEMUL_RECOGNIZED_FILE=ppc64_recognized_file
634 # Define some shell vars to insert bits of code into the standard elf
635 # parse_args and list_options functions.
637 PARSE_AND_LIST_PROLOGUE='
638 #define OPTION_STUBGROUP_SIZE 301
639 #define OPTION_STUBSYMS (OPTION_STUBGROUP_SIZE + 1)
640 #define OPTION_NO_STUBSYMS (OPTION_STUBSYMS + 1)
641 #define OPTION_DOTSYMS (OPTION_NO_STUBSYMS + 1)
642 #define OPTION_NO_DOTSYMS (OPTION_DOTSYMS + 1)
643 #define OPTION_NO_TLS_OPT (OPTION_NO_DOTSYMS + 1)
644 #define OPTION_NO_TLS_GET_ADDR_OPT (OPTION_NO_TLS_OPT + 1)
645 #define OPTION_NO_OPD_OPT (OPTION_NO_TLS_GET_ADDR_OPT + 1)
646 #define OPTION_NO_TOC_OPT (OPTION_NO_OPD_OPT + 1)
647 #define OPTION_NO_MULTI_TOC (OPTION_NO_TOC_OPT + 1)
648 #define OPTION_NO_TOC_SORT (OPTION_NO_MULTI_TOC + 1)
649 #define OPTION_NON_OVERLAPPING_OPD (OPTION_NO_TOC_SORT + 1)
652 PARSE_AND_LIST_LONGOPTS='
653 { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
654 { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
655 { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
656 { "dotsyms", no_argument, NULL, OPTION_DOTSYMS },
657 { "no-dotsyms", no_argument, NULL, OPTION_NO_DOTSYMS },
658 { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
659 { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
660 { "no-opd-optimize", no_argument, NULL, OPTION_NO_OPD_OPT },
661 { "no-toc-optimize", no_argument, NULL, OPTION_NO_TOC_OPT },
662 { "no-multi-toc", no_argument, NULL, OPTION_NO_MULTI_TOC },
663 { "no-toc-sort", no_argument, NULL, OPTION_NO_TOC_SORT },
664 { "non-overlapping-opd", no_argument, NULL, OPTION_NON_OVERLAPPING_OPD },
667 PARSE_AND_LIST_OPTIONS='
669 --stub-group-size=N Maximum size of a group of input sections that\n\
670 can be handled by one stub section. A negative\n\
671 value locates all stubs before their branches\n\
672 (with a group size of -N), while a positive\n\
673 value allows two groups of input sections, one\n\
674 before, and one after each stub section.\n\
675 Values of +/-1 indicate the linker should\n\
676 choose suitable defaults.\n"
679 --emit-stub-syms Label linker stubs with a symbol.\n"
682 --no-emit-stub-syms Don'\''t label linker stubs with a symbol.\n"
685 --dotsyms For every version pattern \"foo\" in a version\n\
686 script, add \".foo\" so that function code\n\
687 symbols are treated the same as function\n\
688 descriptor symbols. Defaults to on.\n"
691 --no-dotsyms Don'\''t do anything special in version scripts.\n"
694 --no-tls-optimize Don'\''t try to optimize TLS accesses.\n"
697 --no-tls-get-addr-optimize Don'\''t use a special __tls_get_addr call.\n"
700 --no-opd-optimize Don'\''t optimize the OPD section.\n"
703 --no-toc-optimize Don'\''t optimize the TOC section.\n"
706 --no-multi-toc Disallow automatic multiple toc sections.\n"
709 --no-toc-sort Don'\''t sort TOC and GOT sections.\n"
712 --non-overlapping-opd Canonicalize .opd, so that there are no\n\
713 overlapping .opd entries.\n"
717 PARSE_AND_LIST_ARGS_CASES='
718 case OPTION_STUBGROUP_SIZE:
721 group_size = bfd_scan_vma (optarg, &end, 0);
723 einfo (_("%P%F: invalid number `%s'\''\n"), optarg);
727 case OPTION_STUBSYMS:
731 case OPTION_NO_STUBSYMS:
739 case OPTION_NO_DOTSYMS:
743 case OPTION_NO_TLS_OPT:
747 case OPTION_NO_TLS_GET_ADDR_OPT:
748 no_tls_get_addr_opt = 1;
751 case OPTION_NO_OPD_OPT:
755 case OPTION_NO_TOC_OPT:
759 case OPTION_NO_MULTI_TOC:
763 case OPTION_NO_TOC_SORT:
767 case OPTION_NON_OVERLAPPING_OPD:
768 non_overlapping_opd = 1;
772 # Put these extra ppc64elf routines in ld_${EMULATION_NAME}_emulation
774 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation
775 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
776 LDEMUL_FINISH=gld${EMULATION_NAME}_finish
777 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_create_output_section_statements
778 LDEMUL_NEW_VERS_PATTERN=gld${EMULATION_NAME}_new_vers_pattern