1 # This shell script emits a C file. -*- C -*-
2 # Copyright 1991-2014 Free Software Foundation, Inc.
4 # This file is part of the GNU Binutils.
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 3 of the License, or
9 # (at your option) any later version.
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.
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., 51 Franklin Street - Fifth Floor, Boston,
22 # This file is sourced from elf32.em, and defines extra arm-elf
25 test -z "$TARGET2_TYPE" && TARGET2_TYPE="rel"
31 static char * thumb_entry_symbol = NULL;
32 static int byteswap_code = 0;
33 static int target1_is_rel = 0${TARGET1_IS_REL};
34 static char * target2_type = "${TARGET2_TYPE}";
35 static int fix_v4bx = 0;
36 static int use_blx = 0;
37 static bfd_arm_vfp11_fix vfp11_denorm_fix = BFD_ARM_VFP11_FIX_DEFAULT;
38 static int fix_cortex_a8 = -1;
39 static int no_enum_size_warning = 0;
40 static int no_wchar_size_warning = 0;
41 static int pic_veneer = 0;
42 static int merge_exidx_entries = -1;
43 static int fix_arm1176 = 1;
46 gld${EMULATION_NAME}_before_parse (void)
48 #ifndef TARGET_ /* I.e., if not generic. */
49 ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown);
50 #endif /* not TARGET_ */
51 input_flags.dynamic = ${DYNAMIC_LINK-TRUE};
52 config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`;
53 config.separate_code = `if test "x${SEPARATE_CODE}" = xyes ; then echo TRUE ; else echo FALSE ; fi`;
57 arm_elf_before_allocation (void)
59 bfd_elf32_arm_set_byteswap_code (&link_info, byteswap_code);
61 /* Choose type of VFP11 erratum fix, or warn if specified fix is unnecessary
62 due to architecture version. */
63 bfd_elf32_arm_set_vfp11_fix (link_info.output_bfd, &link_info);
65 /* Auto-select Cortex-A8 erratum fix if it wasn't explicitly specified. */
66 bfd_elf32_arm_set_cortex_a8_fix (link_info.output_bfd, &link_info);
68 /* We should be able to set the size of the interworking stub section. We
69 can't do it until later if we have dynamic sections, though. */
70 if (elf_hash_table (&link_info)->dynobj == NULL)
72 /* Here we rummage through the found bfds to collect glue information. */
73 LANG_FOR_EACH_INPUT_STATEMENT (is)
75 /* Initialise mapping tables for code/data. */
76 bfd_elf32_arm_init_maps (is->the_bfd);
78 if (!bfd_elf32_arm_process_before_allocation (is->the_bfd,
80 || !bfd_elf32_arm_vfp11_erratum_scan (is->the_bfd, &link_info))
81 /* xgettext:c-format */
82 einfo (_("Errors encountered processing file %s"), is->filename);
85 /* We have seen it all. Allocate it, and carry on. */
86 bfd_elf32_arm_allocate_interworking_sections (& link_info);
89 /* Call the standard elf routine. */
90 gld${EMULATION_NAME}_before_allocation ();
93 /* Fake input file for stubs. */
94 static lang_input_statement_type *stub_file;
96 /* Whether we need to call gldarm_layout_sections_again. */
97 static int need_laying_out = 0;
99 /* Maximum size of a group of input sections that can be handled by
100 one stub section. A value of +/-1 indicates the bfd back-end
101 should use a suitable default size. */
102 static bfd_signed_vma group_size = 1;
104 struct hook_stub_info
106 lang_statement_list_type add;
107 asection *input_section;
110 /* Traverse the linker tree to find the spot where the stub goes. */
113 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
115 lang_statement_union_type *l;
118 for (; (l = *lp) != NULL; lp = &l->header.next)
120 switch (l->header.type)
122 case lang_constructors_statement_enum:
123 ret = hook_in_stub (info, &constructor_list.head);
128 case lang_output_section_statement_enum:
129 ret = hook_in_stub (info,
130 &l->output_section_statement.children.head);
135 case lang_wild_statement_enum:
136 ret = hook_in_stub (info, &l->wild_statement.children.head);
141 case lang_group_statement_enum:
142 ret = hook_in_stub (info, &l->group_statement.children.head);
147 case lang_input_section_enum:
148 if (l->input_section.section == info->input_section)
150 /* We've found our section. Insert the stub immediately
151 after its associated input section. */
152 *(info->add.tail) = l->header.next;
153 l->header.next = info->add.head;
158 case lang_data_statement_enum:
159 case lang_reloc_statement_enum:
160 case lang_object_symbols_statement_enum:
161 case lang_output_statement_enum:
162 case lang_target_statement_enum:
163 case lang_input_statement_enum:
164 case lang_assignment_statement_enum:
165 case lang_padding_statement_enum:
166 case lang_address_statement_enum:
167 case lang_fill_statement_enum:
179 /* Call-back for elf32_arm_size_stubs. */
181 /* Create a new stub section, and arrange for it to be linked
182 immediately after INPUT_SECTION. */
185 elf32_arm_add_stub_section (const char * stub_sec_name,
186 asection * input_section,
187 unsigned int alignment_power)
191 asection *output_section;
192 lang_output_section_statement_type *os;
193 struct hook_stub_info info;
195 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
196 | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
197 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
198 stub_sec_name, flags);
199 if (stub_sec == NULL)
202 bfd_set_section_alignment (stub_file->the_bfd, stub_sec, alignment_power);
204 output_section = input_section->output_section;
205 os = lang_output_section_get (output_section);
207 info.input_section = input_section;
208 lang_list_init (&info.add);
209 lang_add_section (&info.add, stub_sec, NULL, os);
211 if (info.add.head == NULL)
214 if (hook_in_stub (&info, &os->children.head))
218 einfo ("%X%P: can not make stub section: %E\n");
222 /* Another call-back for elf_arm_size_stubs. */
225 gldarm_layout_sections_again (void)
227 /* If we have changed sizes of the stub sections, then we need
228 to recalculate all the section offsets. This may mean we need to
229 add even more stubs. */
230 gld${EMULATION_NAME}_map_segments (TRUE);
231 need_laying_out = -1;
235 build_section_lists (lang_statement_union_type *statement)
237 if (statement->header.type == lang_input_section_enum)
239 asection *i = statement->input_section.section;
241 if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
242 && (i->flags & SEC_EXCLUDE) == 0
243 && i->output_section != NULL
244 && i->output_section->owner == link_info.output_bfd)
245 elf32_arm_next_input_section (& link_info, i);
250 compare_output_sec_vma (const void *a, const void *b)
252 asection *asec = *(asection **) a, *bsec = *(asection **) b;
253 asection *aout = asec->output_section, *bout = bsec->output_section;
256 /* If there's no output section for some reason, compare equal. */
260 avma = aout->vma + asec->output_offset;
261 bvma = bout->vma + bsec->output_offset;
265 else if (avma < bvma)
272 gld${EMULATION_NAME}_after_allocation (void)
274 if (!link_info.relocatable)
276 /* Build a sorted list of input text sections, then use that to process
277 the unwind table index. */
278 unsigned int list_size = 10;
279 asection **sec_list = (asection **)
280 xmalloc (list_size * sizeof (asection *));
281 unsigned int sec_count = 0;
283 LANG_FOR_EACH_INPUT_STATEMENT (is)
285 bfd *abfd = is->the_bfd;
288 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
291 for (sec = abfd->sections; sec != NULL; sec = sec->next)
293 asection *out_sec = sec->output_section;
296 && elf_section_data (sec)
297 && elf_section_type (sec) == SHT_PROGBITS
298 && (elf_section_flags (sec) & SHF_EXECINSTR) != 0
299 && (sec->flags & SEC_EXCLUDE) == 0
300 && sec->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
301 && out_sec != bfd_abs_section_ptr)
303 if (sec_count == list_size)
306 sec_list = (asection **)
307 xrealloc (sec_list, list_size * sizeof (asection *));
310 sec_list[sec_count++] = sec;
315 qsort (sec_list, sec_count, sizeof (asection *), &compare_output_sec_vma);
317 if (elf32_arm_fix_exidx_coverage (sec_list, sec_count, &link_info,
318 merge_exidx_entries))
324 /* bfd_elf32_discard_info just plays with debugging sections,
325 ie. doesn't affect any code, so we can delay resizing the
326 sections. It's likely we'll resize everything in the process of
328 if (bfd_elf_discard_info (link_info.output_bfd, & link_info))
331 /* If generating a relocatable output file, then we don't
332 have to examine the relocs. */
333 if (stub_file != NULL && !link_info.relocatable)
335 int ret = elf32_arm_setup_section_lists (link_info.output_bfd, & link_info);
341 einfo ("%X%P: could not compute sections lists for stub generation: %E\n");
345 lang_for_each_statement (build_section_lists);
347 /* Call into the BFD backend to do the real work. */
348 if (! elf32_arm_size_stubs (link_info.output_bfd,
352 & elf32_arm_add_stub_section,
353 & gldarm_layout_sections_again))
355 einfo ("%X%P: cannot size stub section: %E\n");
361 if (need_laying_out != -1)
362 gld${EMULATION_NAME}_map_segments (need_laying_out);
366 gld${EMULATION_NAME}_finish (void)
368 struct bfd_link_hash_entry * h;
371 LANG_FOR_EACH_INPUT_STATEMENT (is)
373 /* Figure out where VFP11 erratum veneers (and the labels returning
374 from same) have been placed. */
375 bfd_elf32_arm_vfp11_fix_veneer_locations (is->the_bfd, &link_info);
379 if (! link_info.relocatable)
381 /* Now build the linker stubs. */
382 if (stub_file->the_bfd->sections != NULL)
384 if (! elf32_arm_build_stubs (& link_info))
385 einfo ("%X%P: can not build stubs: %E\n");
391 if (thumb_entry_symbol)
393 h = bfd_link_hash_lookup (link_info.hash, thumb_entry_symbol,
398 struct elf_link_hash_entry * eh;
400 if (!entry_symbol.name)
403 h = bfd_link_hash_lookup (link_info.hash, entry_symbol.name,
405 eh = (struct elf_link_hash_entry *)h;
406 if (!h || eh->target_internal != ST_BRANCH_TO_THUMB)
411 if (h != (struct bfd_link_hash_entry *) NULL
412 && (h->type == bfd_link_hash_defined
413 || h->type == bfd_link_hash_defweak)
414 && h->u.def.section->output_section != NULL)
416 static char buffer[32];
419 /* Special procesing is required for a Thumb entry symbol. The
420 bottom bit of its address must be set. */
421 val = (h->u.def.value
422 + bfd_get_section_vma (link_info.output_bfd,
423 h->u.def.section->output_section)
424 + h->u.def.section->output_offset);
428 /* Now convert this value into a string and store it in entry_symbol
429 where the lang_finish() function will pick it up. */
433 sprintf_vma (buffer + 2, val);
435 if (thumb_entry_symbol != NULL && entry_symbol.name != NULL
436 && entry_from_cmdline)
437 einfo (_("%P: warning: '--thumb-entry %s' is overriding '-e %s'\n"),
438 thumb_entry_symbol, entry_symbol.name);
439 entry_symbol.name = buffer;
442 einfo (_("%P: warning: cannot find thumb start symbol %s\n"),
446 /* This is a convenient point to tell BFD about target specific flags.
447 After the output has been created, but before inputs are read. */
449 arm_elf_create_output_section_statements (void)
451 if (strstr (bfd_get_target (link_info.output_bfd), "arm") == NULL)
453 /* The arm backend needs special fields in the output hash structure.
454 These will only be created if the output format is an arm format,
455 hence we do not support linking and changing output formats at the
456 same time. Use a link followed by objcopy to change output formats. */
457 einfo ("%F%X%P: error: Cannot change output format whilst linking ARM binaries.\n");
461 bfd_elf32_arm_set_target_relocs (link_info.output_bfd, &link_info,
463 target2_type, fix_v4bx, use_blx,
464 vfp11_denorm_fix, no_enum_size_warning,
465 no_wchar_size_warning,
466 pic_veneer, fix_cortex_a8,
469 stub_file = lang_add_input_file ("linker stubs",
470 lang_input_file_is_fake_enum,
472 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
473 if (stub_file->the_bfd == NULL
474 || ! bfd_set_arch_mach (stub_file->the_bfd,
475 bfd_get_arch (link_info.output_bfd),
476 bfd_get_mach (link_info.output_bfd)))
478 einfo ("%X%P: can not create BFD %E\n");
482 stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
483 ldlang_add_file (stub_file);
485 /* Also use the stub file for stubs placed in a single output section. */
486 bfd_elf32_arm_add_glue_sections_to_bfd (stub_file->the_bfd, &link_info);
487 bfd_elf32_arm_get_bfd_for_interworking (stub_file->the_bfd, &link_info);
490 /* Avoid processing the fake stub_file in vercheck, stat_needed and
491 check_needed routines. */
493 static void (*real_func) (lang_input_statement_type *);
495 static void arm_for_each_input_file_wrapper (lang_input_statement_type *l)
502 arm_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
505 lang_for_each_input_file (&arm_for_each_input_file_wrapper);
508 #define lang_for_each_input_file arm_lang_for_each_input_file
512 # Define some shell vars to insert bits of code into the standard elf
513 # parse_args and list_options functions.
515 PARSE_AND_LIST_PROLOGUE='
516 #define OPTION_THUMB_ENTRY 301
517 #define OPTION_BE8 302
518 #define OPTION_TARGET1_REL 303
519 #define OPTION_TARGET1_ABS 304
520 #define OPTION_TARGET2 305
521 #define OPTION_FIX_V4BX 306
522 #define OPTION_USE_BLX 307
523 #define OPTION_VFP11_DENORM_FIX 308
524 #define OPTION_NO_ENUM_SIZE_WARNING 309
525 #define OPTION_PIC_VENEER 310
526 #define OPTION_FIX_V4BX_INTERWORKING 311
527 #define OPTION_STUBGROUP_SIZE 312
528 #define OPTION_NO_WCHAR_SIZE_WARNING 313
529 #define OPTION_FIX_CORTEX_A8 314
530 #define OPTION_NO_FIX_CORTEX_A8 315
531 #define OPTION_NO_MERGE_EXIDX_ENTRIES 316
532 #define OPTION_FIX_ARM1176 317
533 #define OPTION_NO_FIX_ARM1176 318
534 #define OPTION_LONG_PLT 319
537 PARSE_AND_LIST_SHORTOPTS=p
539 PARSE_AND_LIST_LONGOPTS='
540 { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
541 { "thumb-entry", required_argument, NULL, OPTION_THUMB_ENTRY},
542 { "be8", no_argument, NULL, OPTION_BE8},
543 { "target1-rel", no_argument, NULL, OPTION_TARGET1_REL},
544 { "target1-abs", no_argument, NULL, OPTION_TARGET1_ABS},
545 { "target2", required_argument, NULL, OPTION_TARGET2},
546 { "fix-v4bx", no_argument, NULL, OPTION_FIX_V4BX},
547 { "fix-v4bx-interworking", no_argument, NULL, OPTION_FIX_V4BX_INTERWORKING},
548 { "use-blx", no_argument, NULL, OPTION_USE_BLX},
549 { "vfp11-denorm-fix", required_argument, NULL, OPTION_VFP11_DENORM_FIX},
550 { "no-enum-size-warning", no_argument, NULL, OPTION_NO_ENUM_SIZE_WARNING},
551 { "pic-veneer", no_argument, NULL, OPTION_PIC_VENEER},
552 { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
553 { "no-wchar-size-warning", no_argument, NULL, OPTION_NO_WCHAR_SIZE_WARNING},
554 { "fix-cortex-a8", no_argument, NULL, OPTION_FIX_CORTEX_A8 },
555 { "no-fix-cortex-a8", no_argument, NULL, OPTION_NO_FIX_CORTEX_A8 },
556 { "no-merge-exidx-entries", no_argument, NULL, OPTION_NO_MERGE_EXIDX_ENTRIES },
557 { "fix-arm1176", no_argument, NULL, OPTION_FIX_ARM1176 },
558 { "no-fix-arm1176", no_argument, NULL, OPTION_NO_FIX_ARM1176 },
559 { "long-plt", no_argument, NULL, OPTION_LONG_PLT },
562 PARSE_AND_LIST_OPTIONS='
563 fprintf (file, _(" --thumb-entry=<sym> Set the entry point to be Thumb symbol <sym>\n"));
564 fprintf (file, _(" --be8 Output BE8 format image\n"));
565 fprintf (file, _(" --target1-rel Interpret R_ARM_TARGET1 as R_ARM_REL32\n"));
566 fprintf (file, _(" --target1-abs Interpret R_ARM_TARGET1 as R_ARM_ABS32\n"));
567 fprintf (file, _(" --target2=<type> Specify definition of R_ARM_TARGET2\n"));
568 fprintf (file, _(" --fix-v4bx Rewrite BX rn as MOV pc, rn for ARMv4\n"));
569 fprintf (file, _(" --fix-v4bx-interworking Rewrite BX rn branch to ARMv4 interworking veneer\n"));
570 fprintf (file, _(" --use-blx Enable use of BLX instructions\n"));
571 fprintf (file, _(" --vfp11-denorm-fix Specify how to fix VFP11 denorm erratum\n"));
572 fprintf (file, _(" --no-enum-size-warning Don'\''t warn about objects with incompatible\n"
574 fprintf (file, _(" --no-wchar-size-warning Don'\''t warn about objects with incompatible\n"
575 " wchar_t sizes\n"));
576 fprintf (file, _(" --pic-veneer Always generate PIC interworking veneers\n"));
577 fprintf (file, _(" --long-plt Generate long .plt entries\n"
578 " to handle large .plt/.got displacements\n"));
580 --stub-group-size=N Maximum size of a group of input sections that\n\
581 can be handled by one stub section. A negative\n\
582 value locates all stubs after their branches\n\
583 (with a group size of -N), while a positive\n\
584 value allows two groups of input sections, one\n\
585 before, and one after each stub section.\n\
586 Values of +/-1 indicate the linker should\n\
587 choose suitable defaults.\n"));
588 fprintf (file, _(" --[no-]fix-cortex-a8 Disable/enable Cortex-A8 Thumb-2 branch erratum fix\n"));
589 fprintf (file, _(" --no-merge-exidx-entries Disable merging exidx entries\n"));
590 fprintf (file, _(" --[no-]fix-arm1176 Disable/enable ARM1176 BLX immediate erratum fix\n"));
593 PARSE_AND_LIST_ARGS_CASES='
595 /* Only here for backwards compatibility. */
598 case OPTION_THUMB_ENTRY:
599 thumb_entry_symbol = optarg;
606 case OPTION_TARGET1_REL:
610 case OPTION_TARGET1_ABS:
615 target2_type = optarg;
618 case OPTION_FIX_V4BX:
622 case OPTION_FIX_V4BX_INTERWORKING:
630 case OPTION_VFP11_DENORM_FIX:
631 if (strcmp (optarg, "none") == 0)
632 vfp11_denorm_fix = BFD_ARM_VFP11_FIX_NONE;
633 else if (strcmp (optarg, "scalar") == 0)
634 vfp11_denorm_fix = BFD_ARM_VFP11_FIX_SCALAR;
635 else if (strcmp (optarg, "vector") == 0)
636 vfp11_denorm_fix = BFD_ARM_VFP11_FIX_VECTOR;
638 einfo (_("Unrecognized VFP11 fix type '\''%s'\''.\n"), optarg);
641 case OPTION_NO_ENUM_SIZE_WARNING:
642 no_enum_size_warning = 1;
645 case OPTION_NO_WCHAR_SIZE_WARNING:
646 no_wchar_size_warning = 1;
649 case OPTION_PIC_VENEER:
653 case OPTION_STUBGROUP_SIZE:
657 group_size = bfd_scan_vma (optarg, &end, 0);
659 einfo (_("%P%F: invalid number `%s'\''\n"), optarg);
663 case OPTION_FIX_CORTEX_A8:
667 case OPTION_NO_FIX_CORTEX_A8:
671 case OPTION_NO_MERGE_EXIDX_ENTRIES:
672 merge_exidx_entries = 0;
675 case OPTION_FIX_ARM1176:
679 case OPTION_NO_FIX_ARM1176:
683 case OPTION_LONG_PLT:
684 bfd_elf32_arm_use_long_plt ();
688 # We have our own before_allocation etc. functions, but they call
689 # the standard routines, so give them a different name.
690 LDEMUL_BEFORE_ALLOCATION=arm_elf_before_allocation
691 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
692 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=arm_elf_create_output_section_statements
694 # Replace the elf before_parse function with our own.
695 LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
697 # Call the extra arm-elf function
698 LDEMUL_FINISH=gld${EMULATION_NAME}_finish