2000-03-08 H.J. Lu (hjl@gnu.org)
[binutils.git] / bfd / elf32-arm.h
blobeaaf9763b4083327ea128d54aa00a3bf3bc882a3
1 /* 32-bit ELF support for ARM
2 Copyright 1998, 1999 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
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.
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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
21 typedef unsigned long int insn32;
22 typedef unsigned short int insn16;
24 static boolean elf32_arm_set_private_flags
25 PARAMS ((bfd *, flagword));
26 static boolean elf32_arm_copy_private_bfd_data
27 PARAMS ((bfd *, bfd *));
28 static boolean elf32_arm_merge_private_bfd_data
29 PARAMS ((bfd *, bfd *));
30 static boolean elf32_arm_print_private_bfd_data
31 PARAMS ((bfd *, PTR));
32 static int elf32_arm_get_symbol_type
33 PARAMS (( Elf_Internal_Sym *, int));
34 static struct bfd_link_hash_table *elf32_arm_link_hash_table_create
35 PARAMS ((bfd *));
36 static bfd_reloc_status_type elf32_arm_final_link_relocate
37 PARAMS ((reloc_howto_type *, bfd *, bfd *, asection *, bfd_byte *,
38 Elf_Internal_Rela *, bfd_vma, struct bfd_link_info *, asection *,
39 const char *, unsigned char, struct elf_link_hash_entry *));
41 static insn32 insert_thumb_branch
42 PARAMS ((insn32, int));
43 static struct elf_link_hash_entry *find_thumb_glue
44 PARAMS ((struct bfd_link_info *, CONST char *, bfd *));
45 static struct elf_link_hash_entry *find_arm_glue
46 PARAMS ((struct bfd_link_info *, CONST char *, bfd *));
47 static void record_arm_to_thumb_glue
48 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
49 static void record_thumb_to_arm_glue
50 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
51 static void elf32_arm_post_process_headers
52 PARAMS ((bfd *, struct bfd_link_info *));
53 static int elf32_arm_to_thumb_stub
54 PARAMS ((struct bfd_link_info *, const char *, bfd *, bfd *, asection *,
55 bfd_byte *, asection *, bfd_vma, bfd_signed_vma, bfd_vma));
56 static int elf32_thumb_to_arm_stub
57 PARAMS ((struct bfd_link_info *, const char *, bfd *, bfd *, asection *,
58 bfd_byte *, asection *, bfd_vma, bfd_signed_vma, bfd_vma));
60 /* The linker script knows the section names for placement.
61 The entry_names are used to do simple name mangling on the stubs.
62 Given a function name, and its type, the stub can be found. The
63 name can be changed. The only requirement is the %s be present.
66 #define INTERWORK_FLAG( abfd ) (elf_elfheader (abfd)->e_flags & EF_INTERWORK)
68 #define THUMB2ARM_GLUE_SECTION_NAME ".glue_7t"
69 #define THUMB2ARM_GLUE_ENTRY_NAME "__%s_from_thumb"
71 #define ARM2THUMB_GLUE_SECTION_NAME ".glue_7"
72 #define ARM2THUMB_GLUE_ENTRY_NAME "__%s_from_arm"
74 /* The name of the dynamic interpreter. This is put in the .interp
75 section. */
76 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/ld.so.1"
78 /* The size in bytes of an entry in the procedure linkage table. */
80 #define PLT_ENTRY_SIZE 16
82 /* The first entry in a procedure linkage table looks like
83 this. It is set up so that any shared library function that is
84 called before the relocation has been set up calls the dynamic
85 linker first */
87 static const bfd_byte elf32_arm_plt0_entry [PLT_ENTRY_SIZE] =
89 0x04, 0xe0, 0x2d, 0xe5, /* str lr, [sp, #-4]! */
90 0x10, 0xe0, 0x9f, 0xe5, /* ldr lr, [pc, #16] */
91 0x0e, 0xe0, 0x8f, 0xe0, /* adr lr, pc, lr */
92 0x08, 0xf0, 0xbe, 0xe5 /* ldr pc, [lr, #8]! */
95 /* Subsequent entries in a procedure linkage table look like
96 this. */
98 static const bfd_byte elf32_arm_plt_entry [PLT_ENTRY_SIZE] =
100 0x04, 0xc0, 0x9f, 0xe5, /* ldr ip, [pc, #4] */
101 0x0c, 0xc0, 0x8f, 0xe0, /* add ip, pc, ip */
102 0x00, 0xf0, 0x9c, 0xe5, /* ldr pc, [ip] */
103 0x00, 0x00, 0x00, 0x00 /* offset to symbol in got */
107 /* The ARM linker needs to keep track of the number of relocs that it
108 decides to copy in check_relocs for each symbol. This is so that
109 it can discard PC relative relocs if it doesn't need them when
110 linking with -Bsymbolic. We store the information in a field
111 extending the regular ELF linker hash table. */
113 /* This structure keeps track of the number of PC relative relocs we
114 have copied for a given symbol. */
116 struct elf32_arm_pcrel_relocs_copied
118 /* Next section. */
119 struct elf32_arm_pcrel_relocs_copied * next;
120 /* A section in dynobj. */
121 asection * section;
122 /* Number of relocs copied in this section. */
123 bfd_size_type count;
126 /* Arm ELF linker hash entry. */
128 struct elf32_arm_link_hash_entry
130 struct elf_link_hash_entry root;
132 /* Number of PC relative relocs copied for this symbol. */
133 struct elf32_arm_pcrel_relocs_copied * pcrel_relocs_copied;
136 /* Declare this now that the above structures are defined. */
138 static boolean elf32_arm_discard_copies
139 PARAMS ((struct elf32_arm_link_hash_entry *, PTR));
141 /* Traverse an arm ELF linker hash table. */
143 #define elf32_arm_link_hash_traverse(table, func, info) \
144 (elf_link_hash_traverse \
145 (&(table)->root, \
146 (boolean (*) PARAMS ((struct elf_link_hash_entry *, PTR))) (func), \
147 (info)))
149 /* Get the ARM elf linker hash table from a link_info structure. */
150 #define elf32_arm_hash_table(info) \
151 ((struct elf32_arm_link_hash_table *) ((info)->hash))
153 /* ARM ELF linker hash table */
154 struct elf32_arm_link_hash_table
156 /* The main hash table. */
157 struct elf_link_hash_table root;
159 /* The size in bytes of the section containg the Thumb-to-ARM glue. */
160 long int thumb_glue_size;
162 /* The size in bytes of the section containg the ARM-to-Thumb glue. */
163 long int arm_glue_size;
165 /* An arbitary input BFD chosen to hold the glue sections. */
166 bfd * bfd_of_glue_owner;
168 /* A boolean indicating whether knowledge of the ARM's pipeline
169 length should be applied by the linker. */
170 int no_pipeline_knowledge;
174 /* Create an entry in an ARM ELF linker hash table. */
176 static struct bfd_hash_entry *
177 elf32_arm_link_hash_newfunc (entry, table, string)
178 struct bfd_hash_entry * entry;
179 struct bfd_hash_table * table;
180 const char * string;
182 struct elf32_arm_link_hash_entry * ret =
183 (struct elf32_arm_link_hash_entry *) entry;
185 /* Allocate the structure if it has not already been allocated by a
186 subclass. */
187 if (ret == (struct elf32_arm_link_hash_entry *) NULL)
188 ret = ((struct elf32_arm_link_hash_entry *)
189 bfd_hash_allocate (table,
190 sizeof (struct elf32_arm_link_hash_entry)));
191 if (ret == (struct elf32_arm_link_hash_entry *) NULL)
192 return (struct bfd_hash_entry *) ret;
194 /* Call the allocation method of the superclass. */
195 ret = ((struct elf32_arm_link_hash_entry *)
196 _bfd_elf_link_hash_newfunc ((struct bfd_hash_entry *) ret,
197 table, string));
198 if (ret != (struct elf32_arm_link_hash_entry *) NULL)
199 ret->pcrel_relocs_copied = NULL;
201 return (struct bfd_hash_entry *) ret;
204 /* Create an ARM elf linker hash table */
206 static struct bfd_link_hash_table *
207 elf32_arm_link_hash_table_create (abfd)
208 bfd *abfd;
210 struct elf32_arm_link_hash_table *ret;
212 ret = ((struct elf32_arm_link_hash_table *)
213 bfd_alloc (abfd, sizeof (struct elf32_arm_link_hash_table)));
214 if (ret == (struct elf32_arm_link_hash_table *) NULL)
215 return NULL;
217 if (!_bfd_elf_link_hash_table_init (&ret->root, abfd,
218 elf32_arm_link_hash_newfunc))
220 bfd_release (abfd, ret);
221 return NULL;
224 ret->thumb_glue_size = 0;
225 ret->arm_glue_size = 0;
226 ret->bfd_of_glue_owner = NULL;
227 ret->no_pipeline_knowledge = 0;
229 return &ret->root.root;
232 static struct elf_link_hash_entry *
233 find_thumb_glue (link_info, name, input_bfd)
234 struct bfd_link_info *link_info;
235 CONST char *name;
236 bfd *input_bfd;
238 char *tmp_name;
239 struct elf_link_hash_entry *hash;
240 struct elf32_arm_link_hash_table *hash_table;
242 /* We need a pointer to the armelf specific hash table. */
243 hash_table = elf32_arm_hash_table (link_info);
246 tmp_name = ((char *)
247 bfd_malloc (strlen (name) + strlen (THUMB2ARM_GLUE_ENTRY_NAME) + 1));
249 BFD_ASSERT (tmp_name);
251 sprintf (tmp_name, THUMB2ARM_GLUE_ENTRY_NAME, name);
253 hash = elf_link_hash_lookup
254 (&(hash_table)->root, tmp_name, false, false, true);
256 if (hash == NULL)
257 /* xgettext:c-format */
258 _bfd_error_handler (_ ("%s: unable to find THUMB glue '%s' for `%s'"),
259 bfd_get_filename (input_bfd), tmp_name, name);
261 free (tmp_name);
263 return hash;
266 static struct elf_link_hash_entry *
267 find_arm_glue (link_info, name, input_bfd)
268 struct bfd_link_info *link_info;
269 CONST char *name;
270 bfd *input_bfd;
272 char *tmp_name;
273 struct elf_link_hash_entry *myh;
274 struct elf32_arm_link_hash_table *hash_table;
276 /* We need a pointer to the elfarm specific hash table. */
277 hash_table = elf32_arm_hash_table (link_info);
279 tmp_name = ((char *)
280 bfd_malloc (strlen (name) + strlen (ARM2THUMB_GLUE_ENTRY_NAME) + 1));
282 BFD_ASSERT (tmp_name);
284 sprintf (tmp_name, ARM2THUMB_GLUE_ENTRY_NAME, name);
286 myh = elf_link_hash_lookup
287 (&(hash_table)->root, tmp_name, false, false, true);
289 if (myh == NULL)
290 /* xgettext:c-format */
291 _bfd_error_handler (_ ("%s: unable to find ARM glue '%s' for `%s'"),
292 bfd_get_filename (input_bfd), tmp_name, name);
294 free (tmp_name);
296 return myh;
300 ARM->Thumb glue:
302 .arm
303 __func_from_arm:
304 ldr r12, __func_addr
305 bx r12
306 __func_addr:
307 .word func @ behave as if you saw a ARM_32 reloc
310 #define ARM2THUMB_GLUE_SIZE 12
311 static const insn32 a2t1_ldr_insn = 0xe59fc000;
312 static const insn32 a2t2_bx_r12_insn = 0xe12fff1c;
313 static const insn32 a2t3_func_addr_insn = 0x00000001;
316 Thumb->ARM: Thumb->(non-interworking aware) ARM
318 .thumb .thumb
319 .align 2 .align 2
320 __func_from_thumb: __func_from_thumb:
321 bx pc push {r6, lr}
322 nop ldr r6, __func_addr
323 .arm mov lr, pc
324 __func_change_to_arm: bx r6
325 b func .arm
326 __func_back_to_thumb:
327 ldmia r13! {r6, lr}
328 bx lr
329 __func_addr:
330 .word func
333 #define THUMB2ARM_GLUE_SIZE 8
334 static const insn16 t2a1_bx_pc_insn = 0x4778;
335 static const insn16 t2a2_noop_insn = 0x46c0;
336 static const insn32 t2a3_b_insn = 0xea000000;
338 static const insn16 t2a1_push_insn = 0xb540;
339 static const insn16 t2a2_ldr_insn = 0x4e03;
340 static const insn16 t2a3_mov_insn = 0x46fe;
341 static const insn16 t2a4_bx_insn = 0x4730;
342 static const insn32 t2a5_pop_insn = 0xe8bd4040;
343 static const insn32 t2a6_bx_insn = 0xe12fff1e;
345 boolean
346 bfd_elf32_arm_allocate_interworking_sections (info)
347 struct bfd_link_info * info;
349 asection * s;
350 bfd_byte * foo;
351 struct elf32_arm_link_hash_table * globals;
353 globals = elf32_arm_hash_table (info);
355 BFD_ASSERT (globals != NULL);
357 if (globals->arm_glue_size != 0)
359 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
361 s = bfd_get_section_by_name
362 (globals->bfd_of_glue_owner, ARM2THUMB_GLUE_SECTION_NAME);
364 BFD_ASSERT (s != NULL);
366 foo = (bfd_byte *) bfd_alloc
367 (globals->bfd_of_glue_owner, globals->arm_glue_size);
369 s->_raw_size = s->_cooked_size = globals->arm_glue_size;
370 s->contents = foo;
373 if (globals->thumb_glue_size != 0)
375 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
377 s = bfd_get_section_by_name
378 (globals->bfd_of_glue_owner, THUMB2ARM_GLUE_SECTION_NAME);
380 BFD_ASSERT (s != NULL);
382 foo = (bfd_byte *) bfd_alloc
383 (globals->bfd_of_glue_owner, globals->thumb_glue_size);
385 s->_raw_size = s->_cooked_size = globals->thumb_glue_size;
386 s->contents = foo;
389 return true;
392 static void
393 record_arm_to_thumb_glue (link_info, h)
394 struct bfd_link_info * link_info;
395 struct elf_link_hash_entry * h;
397 const char * name = h->root.root.string;
398 register asection * s;
399 char * tmp_name;
400 struct elf_link_hash_entry * myh;
401 struct elf32_arm_link_hash_table * globals;
403 globals = elf32_arm_hash_table (link_info);
405 BFD_ASSERT (globals != NULL);
406 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
408 s = bfd_get_section_by_name
409 (globals->bfd_of_glue_owner, ARM2THUMB_GLUE_SECTION_NAME);
412 BFD_ASSERT (s != NULL);
414 tmp_name = ((char *)
415 bfd_malloc (strlen (name) + strlen (ARM2THUMB_GLUE_ENTRY_NAME) + 1));
417 BFD_ASSERT (tmp_name);
419 sprintf (tmp_name, ARM2THUMB_GLUE_ENTRY_NAME, name);
421 myh = elf_link_hash_lookup
422 (&(globals)->root, tmp_name, false, false, true);
424 if (myh != NULL)
426 free (tmp_name);
427 return; /* we've already seen this guy */
430 /* The only trick here is using hash_table->arm_glue_size as the value. Even
431 though the section isn't allocated yet, this is where we will be putting
432 it. */
434 _bfd_generic_link_add_one_symbol (link_info, globals->bfd_of_glue_owner, tmp_name,
435 BSF_GLOBAL,
436 s, globals->arm_glue_size + 1,
437 NULL, true, false,
438 (struct bfd_link_hash_entry **) &myh);
440 free (tmp_name);
442 globals->arm_glue_size += ARM2THUMB_GLUE_SIZE;
444 return;
447 static void
448 record_thumb_to_arm_glue (link_info, h)
449 struct bfd_link_info *link_info;
450 struct elf_link_hash_entry *h;
452 const char *name = h->root.root.string;
453 register asection *s;
454 char *tmp_name;
455 struct elf_link_hash_entry *myh;
456 struct elf32_arm_link_hash_table *hash_table;
457 char bind;
459 hash_table = elf32_arm_hash_table (link_info);
461 BFD_ASSERT (hash_table != NULL);
462 BFD_ASSERT (hash_table->bfd_of_glue_owner != NULL);
464 s = bfd_get_section_by_name
465 (hash_table->bfd_of_glue_owner, THUMB2ARM_GLUE_SECTION_NAME);
467 BFD_ASSERT (s != NULL);
469 tmp_name = (char *) bfd_malloc (strlen (name) + strlen (THUMB2ARM_GLUE_ENTRY_NAME) + 1);
471 BFD_ASSERT (tmp_name);
473 sprintf (tmp_name, THUMB2ARM_GLUE_ENTRY_NAME, name);
475 myh = elf_link_hash_lookup
476 (&(hash_table)->root, tmp_name, false, false, true);
478 if (myh != NULL)
480 free (tmp_name);
481 return; /* we've already seen this guy */
484 _bfd_generic_link_add_one_symbol (link_info, hash_table->bfd_of_glue_owner, tmp_name,
485 BSF_GLOBAL, s, hash_table->thumb_glue_size + 1,
486 NULL, true, false,
487 (struct bfd_link_hash_entry **) &myh);
489 /* If we mark it 'thumb', the disassembler will do a better job. */
490 bind = ELF_ST_BIND (myh->type);
491 myh->type = ELF_ST_INFO (bind, STT_ARM_TFUNC);
493 free (tmp_name);
495 /* Allocate another symbol to mark where we switch to arm mode. */
497 #define CHANGE_TO_ARM "__%s_change_to_arm"
498 #define BACK_FROM_ARM "__%s_back_from_arm"
500 tmp_name = (char *) bfd_malloc (strlen (name) + strlen (CHANGE_TO_ARM) + 1);
502 BFD_ASSERT (tmp_name);
504 sprintf (tmp_name, CHANGE_TO_ARM, name);
506 myh = NULL;
508 _bfd_generic_link_add_one_symbol (link_info, hash_table->bfd_of_glue_owner, tmp_name,
509 BSF_LOCAL, s, hash_table->thumb_glue_size + 4,
510 NULL, true, false,
511 (struct bfd_link_hash_entry **) &myh);
513 free (tmp_name);
515 hash_table->thumb_glue_size += THUMB2ARM_GLUE_SIZE;
517 return;
520 /* Select a BFD to be used to hold the sections used by the glue code.
521 This function is called from the linker scripts in ld/emultempl/
522 {armelf/pe}.em */
523 boolean
524 bfd_elf32_arm_get_bfd_for_interworking (abfd, info)
525 bfd *abfd;
526 struct bfd_link_info *info;
528 struct elf32_arm_link_hash_table *globals;
529 flagword flags;
530 asection *sec;
532 /* If we are only performing a partial link do not bother
533 getting a bfd to hold the glue. */
534 if (info->relocateable)
535 return true;
537 globals = elf32_arm_hash_table (info);
539 BFD_ASSERT (globals != NULL);
541 if (globals->bfd_of_glue_owner != NULL)
542 return true;
544 sec = bfd_get_section_by_name (abfd, ARM2THUMB_GLUE_SECTION_NAME);
546 if (sec == NULL)
548 /* Note: we do not include the flag SEC_LINKER_CREATED, as this
549 will prevent elf_link_input_bfd() from processing the contents
550 of this section. */
551 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_CODE | SEC_READONLY;
553 sec = bfd_make_section (abfd, ARM2THUMB_GLUE_SECTION_NAME);
555 if (sec == NULL
556 || !bfd_set_section_flags (abfd, sec, flags)
557 || !bfd_set_section_alignment (abfd, sec, 2))
558 return false;
560 /* Set the gc mark to prevent the section from being removed by garbage
561 collection, despite the fact that no relocs refer to this section. */
562 sec->gc_mark = 1;
565 sec = bfd_get_section_by_name (abfd, THUMB2ARM_GLUE_SECTION_NAME);
567 if (sec == NULL)
569 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_CODE | SEC_READONLY;
571 sec = bfd_make_section (abfd, THUMB2ARM_GLUE_SECTION_NAME);
573 if (sec == NULL
574 || !bfd_set_section_flags (abfd, sec, flags)
575 || !bfd_set_section_alignment (abfd, sec, 2))
576 return false;
578 sec->gc_mark = 1;
581 /* Save the bfd for later use. */
582 globals->bfd_of_glue_owner = abfd;
584 return true;
587 boolean
588 bfd_elf32_arm_process_before_allocation (abfd, link_info, no_pipeline_knowledge)
589 bfd *abfd;
590 struct bfd_link_info *link_info;
591 int no_pipeline_knowledge;
593 Elf_Internal_Shdr *symtab_hdr;
594 Elf_Internal_Rela *free_relocs = NULL;
595 Elf_Internal_Rela *irel, *irelend;
596 bfd_byte *contents = NULL;
597 bfd_byte *free_contents = NULL;
598 Elf32_External_Sym *extsyms = NULL;
599 Elf32_External_Sym *free_extsyms = NULL;
601 asection *sec;
602 struct elf32_arm_link_hash_table *globals;
604 /* If we are only performing a partial link do not bother
605 to construct any glue. */
606 if (link_info->relocateable)
607 return true;
609 /* Here we have a bfd that is to be included on the link. We have a hook
610 to do reloc rummaging, before section sizes are nailed down. */
612 globals = elf32_arm_hash_table (link_info);
614 BFD_ASSERT (globals != NULL);
615 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
617 globals->no_pipeline_knowledge = no_pipeline_knowledge;
619 /* Rummage around all the relocs and map the glue vectors. */
620 sec = abfd->sections;
622 if (sec == NULL)
623 return true;
625 for (; sec != NULL; sec = sec->next)
627 if (sec->reloc_count == 0)
628 continue;
630 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
631 /* Load the relocs. */
633 irel = (_bfd_elf32_link_read_relocs (abfd, sec, (PTR) NULL,
634 (Elf_Internal_Rela *) NULL, false));
636 BFD_ASSERT (irel != 0);
638 irelend = irel + sec->reloc_count;
639 for (; irel < irelend; irel++)
641 long r_type;
642 unsigned long r_index;
644 struct elf_link_hash_entry *h;
646 r_type = ELF32_R_TYPE (irel->r_info);
647 r_index = ELF32_R_SYM (irel->r_info);
649 /* These are the only relocation types we care about */
650 if ( r_type != R_ARM_PC24
651 && r_type != R_ARM_THM_PC22)
652 continue;
654 /* Get the section contents if we haven't done so already. */
655 if (contents == NULL)
657 /* Get cached copy if it exists. */
658 if (elf_section_data (sec)->this_hdr.contents != NULL)
659 contents = elf_section_data (sec)->this_hdr.contents;
660 else
662 /* Go get them off disk. */
663 contents = (bfd_byte *) bfd_malloc (sec->_raw_size);
664 if (contents == NULL)
665 goto error_return;
666 free_contents = contents;
668 if (!bfd_get_section_contents (abfd, sec, contents,
669 (file_ptr) 0, sec->_raw_size))
670 goto error_return;
674 /* Read this BFD's symbols if we haven't done so already. */
675 if (extsyms == NULL)
677 /* Get cached copy if it exists. */
678 if (symtab_hdr->contents != NULL)
679 extsyms = (Elf32_External_Sym *) symtab_hdr->contents;
680 else
682 /* Go get them off disk. */
683 extsyms = ((Elf32_External_Sym *)
684 bfd_malloc (symtab_hdr->sh_size));
685 if (extsyms == NULL)
686 goto error_return;
687 free_extsyms = extsyms;
688 if (bfd_seek (abfd, symtab_hdr->sh_offset, SEEK_SET) != 0
689 || (bfd_read (extsyms, 1, symtab_hdr->sh_size, abfd)
690 != symtab_hdr->sh_size))
691 goto error_return;
695 /* If the relocation is not against a symbol it cannot concern us. */
697 h = NULL;
699 /* We don't care about local symbols */
700 if (r_index < symtab_hdr->sh_info)
701 continue;
703 /* This is an external symbol */
704 r_index -= symtab_hdr->sh_info;
705 h = (struct elf_link_hash_entry *)
706 elf_sym_hashes (abfd)[r_index];
708 /* If the relocation is against a static symbol it must be within
709 the current section and so cannot be a cross ARM/Thumb relocation. */
710 if (h == NULL)
711 continue;
713 switch (r_type)
715 case R_ARM_PC24:
716 /* This one is a call from arm code. We need to look up
717 the target of the call. If it is a thumb target, we
718 insert glue. */
720 if (ELF_ST_TYPE(h->type) == STT_ARM_TFUNC)
721 record_arm_to_thumb_glue (link_info, h);
722 break;
724 case R_ARM_THM_PC22:
725 /* This one is a call from thumb code. We look
726 up the target of the call. If it is not a thumb
727 target, we insert glue. */
729 if (ELF_ST_TYPE (h->type) != STT_ARM_TFUNC)
730 record_thumb_to_arm_glue (link_info, h);
731 break;
733 default:
734 break;
739 return true;
741 error_return:
742 if (free_relocs != NULL)
743 free (free_relocs);
744 if (free_contents != NULL)
745 free (free_contents);
746 if (free_extsyms != NULL)
747 free (free_extsyms);
749 return false;
752 /* The thumb form of a long branch is a bit finicky, because the offset
753 encoding is split over two fields, each in it's own instruction. They
754 can occur in any order. So given a thumb form of long branch, and an
755 offset, insert the offset into the thumb branch and return finished
756 instruction.
758 It takes two thumb instructions to encode the target address. Each has
759 11 bits to invest. The upper 11 bits are stored in one (identifed by
760 H-0.. see below), the lower 11 bits are stored in the other (identified
761 by H-1).
763 Combine together and shifted left by 1 (it's a half word address) and
764 there you have it.
766 Op: 1111 = F,
767 H-0, upper address-0 = 000
768 Op: 1111 = F,
769 H-1, lower address-0 = 800
771 They can be ordered either way, but the arm tools I've seen always put
772 the lower one first. It probably doesn't matter. krk@cygnus.com
774 XXX: Actually the order does matter. The second instruction (H-1)
775 moves the computed address into the PC, so it must be the second one
776 in the sequence. The problem, however is that whilst little endian code
777 stores the instructions in HI then LOW order, big endian code does the
778 reverse. nickc@cygnus.com */
780 #define LOW_HI_ORDER 0xF800F000
781 #define HI_LOW_ORDER 0xF000F800
783 static insn32
784 insert_thumb_branch (br_insn, rel_off)
785 insn32 br_insn;
786 int rel_off;
788 unsigned int low_bits;
789 unsigned int high_bits;
792 BFD_ASSERT ((rel_off & 1) != 1);
794 rel_off >>= 1; /* half word aligned address */
795 low_bits = rel_off & 0x000007FF; /* the bottom 11 bits */
796 high_bits = (rel_off >> 11) & 0x000007FF; /* the top 11 bits */
798 if ((br_insn & LOW_HI_ORDER) == LOW_HI_ORDER)
799 br_insn = LOW_HI_ORDER | (low_bits << 16) | high_bits;
800 else if ((br_insn & HI_LOW_ORDER) == HI_LOW_ORDER)
801 br_insn = HI_LOW_ORDER | (high_bits << 16) | low_bits;
802 else
803 abort (); /* error - not a valid branch instruction form */
805 /* FIXME: abort is probably not the right call. krk@cygnus.com */
807 return br_insn;
810 /* Thumb code calling an ARM function */
811 static int
812 elf32_thumb_to_arm_stub (info, name, input_bfd, output_bfd, input_section,
813 hit_data, sym_sec, offset, addend, val)
814 struct bfd_link_info * info;
815 const char * name;
816 bfd * input_bfd;
817 bfd * output_bfd;
818 asection * input_section;
819 bfd_byte * hit_data;
820 asection * sym_sec;
821 bfd_vma offset;
822 bfd_signed_vma addend;
823 bfd_vma val;
825 asection * s = 0;
826 long int my_offset;
827 unsigned long int tmp;
828 long int ret_offset;
829 struct elf_link_hash_entry * myh;
830 struct elf32_arm_link_hash_table * globals;
832 myh = find_thumb_glue (info, name, input_bfd);
833 if (myh == NULL)
834 return false;
836 globals = elf32_arm_hash_table (info);
838 BFD_ASSERT (globals != NULL);
839 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
841 my_offset = myh->root.u.def.value;
843 s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
844 THUMB2ARM_GLUE_SECTION_NAME);
846 BFD_ASSERT (s != NULL);
847 BFD_ASSERT (s->contents != NULL);
848 BFD_ASSERT (s->output_section != NULL);
850 if ((my_offset & 0x01) == 0x01)
852 if (sym_sec != NULL
853 && sym_sec->owner != NULL
854 && !INTERWORK_FLAG (sym_sec->owner))
856 _bfd_error_handler
857 (_ ("%s(%s): warning: interworking not enabled."),
858 bfd_get_filename (sym_sec->owner), name);
859 _bfd_error_handler
860 (_ (" first occurrence: %s: thumb call to arm"),
861 bfd_get_filename (input_bfd));
863 return false;
866 --my_offset;
867 myh->root.u.def.value = my_offset;
869 bfd_put_16 (output_bfd, t2a1_bx_pc_insn,
870 s->contents + my_offset);
872 bfd_put_16 (output_bfd, t2a2_noop_insn,
873 s->contents + my_offset + 2);
875 ret_offset =
876 ((bfd_signed_vma) val) /* Address of destination of the stub */
877 - ((bfd_signed_vma)
878 (s->output_offset /* Offset from the start of the current section to the start of the stubs. */
879 + my_offset /* Offset of the start of this stub from the start of the stubs. */
880 + s->output_section->vma) /* Address of the start of the current section. */
881 + 4 /* The branch instruction is 4 bytes into the stub. */
882 + 8); /* ARM branches work from the pc of the instruction + 8. */
884 bfd_put_32 (output_bfd,
885 t2a3_b_insn | ((ret_offset >> 2) & 0x00FFFFFF),
886 s->contents + my_offset + 4);
889 BFD_ASSERT (my_offset <= globals->thumb_glue_size);
891 /* Now go back and fix up the original BL insn to point
892 to here. */
893 ret_offset =
894 s->output_offset
895 + my_offset
896 - (input_section->output_offset
897 + offset + addend)
898 - 8;
900 tmp = bfd_get_32 (input_bfd, hit_data
901 - input_section->vma);
903 bfd_put_32 (output_bfd,
904 insert_thumb_branch (tmp, ret_offset),
905 hit_data - input_section->vma);
907 return true;
910 /* Arm code calling a Thumb function */
911 static int
912 elf32_arm_to_thumb_stub (info, name, input_bfd, output_bfd, input_section,
913 hit_data, sym_sec, offset, addend, val)
914 struct bfd_link_info * info;
915 const char * name;
916 bfd * input_bfd;
917 bfd * output_bfd;
918 asection * input_section;
919 bfd_byte * hit_data;
920 asection * sym_sec;
921 bfd_vma offset;
922 bfd_signed_vma addend;
923 bfd_vma val;
925 unsigned long int tmp;
926 long int my_offset;
927 asection * s;
928 long int ret_offset;
929 struct elf_link_hash_entry * myh;
930 struct elf32_arm_link_hash_table * globals;
932 myh = find_arm_glue (info, name, input_bfd);
933 if (myh == NULL)
934 return false;
936 globals = elf32_arm_hash_table (info);
938 BFD_ASSERT (globals != NULL);
939 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
941 my_offset = myh->root.u.def.value;
942 s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
943 ARM2THUMB_GLUE_SECTION_NAME);
944 BFD_ASSERT (s != NULL);
945 BFD_ASSERT (s->contents != NULL);
946 BFD_ASSERT (s->output_section != NULL);
948 if ((my_offset & 0x01) == 0x01)
950 if (sym_sec != NULL
951 && sym_sec->owner != NULL
952 && !INTERWORK_FLAG (sym_sec->owner))
954 _bfd_error_handler
955 (_ ("%s(%s): warning: interworking not enabled."),
956 bfd_get_filename (sym_sec->owner), name);
957 _bfd_error_handler
958 (_ (" first occurrence: %s: arm call to thumb"),
959 bfd_get_filename (input_bfd));
961 --my_offset;
962 myh->root.u.def.value = my_offset;
964 bfd_put_32 (output_bfd, a2t1_ldr_insn,
965 s->contents + my_offset);
967 bfd_put_32 (output_bfd, a2t2_bx_r12_insn,
968 s->contents + my_offset + 4);
970 /* It's a thumb address. Add the low order bit. */
971 bfd_put_32 (output_bfd, val | a2t3_func_addr_insn,
972 s->contents + my_offset + 8);
975 BFD_ASSERT (my_offset <= globals->arm_glue_size);
977 tmp = bfd_get_32 (input_bfd, hit_data);
978 tmp = tmp & 0xFF000000;
980 /* Somehow these are both 4 too far, so subtract 8. */
981 ret_offset = s->output_offset
982 + my_offset
983 + s->output_section->vma
984 - (input_section->output_offset
985 + input_section->output_section->vma
986 + offset + addend)
987 - 8;
989 tmp = tmp | ((ret_offset >> 2) & 0x00FFFFFF);
991 bfd_put_32 (output_bfd, tmp, hit_data
992 - input_section->vma);
994 return true;
997 /* Perform a relocation as part of a final link. */
998 static bfd_reloc_status_type
999 elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
1000 input_section, contents, rel, value,
1001 info, sym_sec, sym_name, sym_flags, h)
1002 reloc_howto_type * howto;
1003 bfd * input_bfd;
1004 bfd * output_bfd;
1005 asection * input_section;
1006 bfd_byte * contents;
1007 Elf_Internal_Rela * rel;
1008 bfd_vma value;
1009 struct bfd_link_info * info;
1010 asection * sym_sec;
1011 const char * sym_name;
1012 unsigned char sym_flags;
1013 struct elf_link_hash_entry * h;
1015 unsigned long r_type = howto->type;
1016 unsigned long r_symndx;
1017 bfd_byte * hit_data = contents + rel->r_offset;
1018 bfd * dynobj = NULL;
1019 Elf_Internal_Shdr * symtab_hdr;
1020 struct elf_link_hash_entry ** sym_hashes;
1021 bfd_vma * local_got_offsets;
1022 asection * sgot = NULL;
1023 asection * splt = NULL;
1024 asection * sreloc = NULL;
1025 bfd_vma addend;
1026 bfd_signed_vma signed_addend;
1027 struct elf32_arm_link_hash_table * globals;
1029 globals = elf32_arm_hash_table (info);
1031 dynobj = elf_hash_table (info)->dynobj;
1032 if (dynobj)
1034 sgot = bfd_get_section_by_name (dynobj, ".got");
1035 splt = bfd_get_section_by_name (dynobj, ".plt");
1037 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1038 sym_hashes = elf_sym_hashes (input_bfd);
1039 local_got_offsets = elf_local_got_offsets (input_bfd);
1040 r_symndx = ELF32_R_SYM (rel->r_info);
1042 #ifdef USE_REL
1043 addend = bfd_get_32 (input_bfd, hit_data) & howto->src_mask;
1045 if (addend & ((howto->src_mask + 1) >> 1))
1047 signed_addend = -1;
1048 signed_addend &= ~ howto->src_mask;
1049 signed_addend |= addend;
1051 else
1052 signed_addend = addend;
1053 #else
1054 addend = signed_addend = rel->r_addend;
1055 #endif
1057 switch (r_type)
1059 case R_ARM_NONE:
1060 return bfd_reloc_ok;
1062 case R_ARM_PC24:
1063 case R_ARM_ABS32:
1064 case R_ARM_REL32:
1065 /* When generating a shared object, these relocations are copied
1066 into the output file to be resolved at run time. */
1068 if (info->shared
1069 && (r_type != R_ARM_PC24
1070 || (h != NULL
1071 && h->dynindx != -1
1072 && (! info->symbolic
1073 || (h->elf_link_hash_flags
1074 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1076 Elf_Internal_Rel outrel;
1077 boolean skip, relocate;
1079 if (sreloc == NULL)
1081 const char * name;
1083 name = (bfd_elf_string_from_elf_section
1084 (input_bfd,
1085 elf_elfheader (input_bfd)->e_shstrndx,
1086 elf_section_data (input_section)->rel_hdr.sh_name));
1087 if (name == NULL)
1088 return bfd_reloc_notsupported;
1090 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
1091 && strcmp (bfd_get_section_name (input_bfd,
1092 input_section),
1093 name + 4) == 0);
1095 sreloc = bfd_get_section_by_name (dynobj, name);
1096 BFD_ASSERT (sreloc != NULL);
1099 skip = false;
1101 if (elf_section_data (input_section)->stab_info == NULL)
1102 outrel.r_offset = rel->r_offset;
1103 else
1105 bfd_vma off;
1107 off = (_bfd_stab_section_offset
1108 (output_bfd, &elf_hash_table (info)->stab_info,
1109 input_section,
1110 & elf_section_data (input_section)->stab_info,
1111 rel->r_offset));
1112 if (off == (bfd_vma) -1)
1113 skip = true;
1114 outrel.r_offset = off;
1117 outrel.r_offset += (input_section->output_section->vma
1118 + input_section->output_offset);
1120 if (skip)
1122 memset (&outrel, 0, sizeof outrel);
1123 relocate = false;
1125 else if (r_type == R_ARM_PC24)
1127 BFD_ASSERT (h != NULL && h->dynindx != -1);
1128 if ((input_section->flags & SEC_ALLOC) != 0)
1129 relocate = false;
1130 else
1131 relocate = true;
1132 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_PC24);
1134 else
1136 if (h == NULL
1137 || ((info->symbolic || h->dynindx == -1)
1138 && (h->elf_link_hash_flags
1139 & ELF_LINK_HASH_DEF_REGULAR) != 0))
1141 relocate = true;
1142 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1144 else
1146 BFD_ASSERT (h->dynindx != -1);
1147 if ((input_section->flags & SEC_ALLOC) != 0)
1148 relocate = false;
1149 else
1150 relocate = true;
1151 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_ABS32);
1155 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1156 (((Elf32_External_Rel *)
1157 sreloc->contents)
1158 + sreloc->reloc_count));
1159 ++sreloc->reloc_count;
1161 /* If this reloc is against an external symbol, we do not want to
1162 fiddle with the addend. Otherwise, we need to include the symbol
1163 value so that it becomes an addend for the dynamic reloc. */
1164 if (! relocate)
1165 return bfd_reloc_ok;
1168 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1169 contents, rel->r_offset, value,
1170 (bfd_vma) 0);
1172 else switch (r_type)
1174 case R_ARM_PC24:
1175 /* Arm B/BL instruction */
1177 /* Check for arm calling thumb function. */
1178 if (sym_flags == STT_ARM_TFUNC)
1180 elf32_arm_to_thumb_stub (info, sym_name, input_bfd, output_bfd,
1181 input_section, hit_data, sym_sec, rel->r_offset,
1182 signed_addend, value);
1183 return bfd_reloc_ok;
1186 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1187 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0)
1189 /* The old way of doing things. Trearing the addend as a
1190 byte sized field and adding in the pipeline offset. */
1192 value -= (input_section->output_section->vma
1193 + input_section->output_offset);
1194 value -= rel->r_offset;
1195 value += addend;
1197 if (! globals->no_pipeline_knowledge)
1198 value -= 8;
1200 else
1202 /* The ARM ELF ABI says that this reloc is computed as: S - P + A
1203 where:
1204 S is the address of the symbol in the relocation.
1205 P is address of the instruction being relocated.
1206 A is the addend (extracted from the instruction) in bytes.
1208 S is held in 'value'.
1209 P is the base address of the section containing the instruction
1210 plus the offset of the reloc into that section, ie:
1211 (input_section->output_section->vma +
1212 input_section->output_offset +
1213 rel->r_offset).
1214 A is the addend, converted into bytes, ie:
1215 (signed_addend * 4)
1217 Note: None of these operations have knowledge of the pipeline
1218 size of the processor, thus it is up to the assembler to encode
1219 this information into the addend. */
1221 value -= (input_section->output_section->vma
1222 + input_section->output_offset);
1223 value -= rel->r_offset;
1224 value += (signed_addend << howto->size);
1226 /* Previous versions of this code also used to add in the pipeline
1227 offset here. This is wrong because the linker is not supposed
1228 to know about such things, and one day it might change. In order
1229 to support old binaries that need the old behaviour however, so
1230 we attempt to detect which ABI was used to create the reloc. */
1231 if (! globals->no_pipeline_knowledge)
1233 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
1235 i_ehdrp = elf_elfheader (input_bfd);
1237 if (i_ehdrp->e_ident[EI_OSABI] == 0)
1238 value -= 8;
1242 /* It is not an error for an undefined weak reference to be
1243 out of range. Any program that branches to such a symbol
1244 is going to crash anyway, so there is no point worrying
1245 about getting the destination exactly right. */
1246 if (! h || h->root.type != bfd_link_hash_undefweak)
1248 /* Perform a signed range check. */
1249 signed_addend = value;
1250 signed_addend >>= howto->rightshift;
1251 if (signed_addend > ((bfd_signed_vma)(howto->dst_mask >> 1))
1252 || signed_addend < - ((bfd_signed_vma) ((howto->dst_mask + 1) >> 1)))
1253 return bfd_reloc_overflow;
1256 value = (signed_addend & howto->dst_mask)
1257 | (bfd_get_32 (input_bfd, hit_data) & (~ howto->dst_mask));
1258 break;
1260 case R_ARM_ABS32:
1261 value += addend;
1262 if (sym_flags == STT_ARM_TFUNC)
1263 value |= 1;
1264 break;
1266 case R_ARM_REL32:
1267 value -= (input_section->output_section->vma
1268 + input_section->output_offset);
1269 value += addend;
1270 break;
1273 bfd_put_32 (input_bfd, value, hit_data);
1274 return bfd_reloc_ok;
1276 case R_ARM_ABS8:
1277 value += addend;
1278 if ((long) value > 0x7f || (long) value < -0x80)
1279 return bfd_reloc_overflow;
1281 bfd_put_8 (input_bfd, value, hit_data);
1282 return bfd_reloc_ok;
1284 case R_ARM_ABS16:
1285 value += addend;
1287 if ((long) value > 0x7fff || (long) value < -0x8000)
1288 return bfd_reloc_overflow;
1290 bfd_put_16 (input_bfd, value, hit_data);
1291 return bfd_reloc_ok;
1293 case R_ARM_ABS12:
1294 /* Support ldr and str instruction for the arm */
1295 /* Also thumb b (unconditional branch). ??? Really? */
1296 value += addend;
1298 if ((long) value > 0x7ff || (long) value < -0x800)
1299 return bfd_reloc_overflow;
1301 value |= (bfd_get_32 (input_bfd, hit_data) & 0xfffff000);
1302 bfd_put_32 (input_bfd, value, hit_data);
1303 return bfd_reloc_ok;
1305 case R_ARM_THM_ABS5:
1306 /* Support ldr and str instructions for the thumb. */
1307 #ifdef USE_REL
1308 /* Need to refetch addend. */
1309 addend = bfd_get_16 (input_bfd, hit_data) & howto->src_mask;
1310 /* ??? Need to determine shift amount from operand size. */
1311 addend >>= howto->rightshift;
1312 #endif
1313 value += addend;
1315 /* ??? Isn't value unsigned? */
1316 if ((long) value > 0x1f || (long) value < -0x10)
1317 return bfd_reloc_overflow;
1319 /* ??? Value needs to be properly shifted into place first. */
1320 value |= bfd_get_16 (input_bfd, hit_data) & 0xf83f;
1321 bfd_put_16 (input_bfd, value, hit_data);
1322 return bfd_reloc_ok;
1324 case R_ARM_THM_PC22:
1325 /* Thumb BL (branch long instruction). */
1327 bfd_vma relocation;
1328 boolean overflow = false;
1329 bfd_vma upper_insn = bfd_get_16 (input_bfd, hit_data);
1330 bfd_vma lower_insn = bfd_get_16 (input_bfd, hit_data + 2);
1331 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
1332 bfd_signed_vma reloc_signed_min = ~ reloc_signed_max;
1333 bfd_vma check;
1334 bfd_signed_vma signed_check;
1336 #ifdef USE_REL
1337 /* Need to refetch the addend and squish the two 11 bit pieces
1338 together. */
1340 bfd_vma upper = upper_insn & 0x7ff;
1341 bfd_vma lower = lower_insn & 0x7ff;
1342 upper = (upper ^ 0x400) - 0x400; /* sign extend */
1343 addend = (upper << 12) | (lower << 1);
1344 signed_addend = addend;
1346 #endif
1348 /* If it is not a call to thumb, assume call to arm.
1349 If it is a call relative to a section name, then it is not a
1350 function call at all, but rather a long jump. */
1351 if (sym_flags != STT_ARM_TFUNC && sym_flags != STT_SECTION)
1353 if (elf32_thumb_to_arm_stub
1354 (info, sym_name, input_bfd, output_bfd, input_section,
1355 hit_data, sym_sec, rel->r_offset, signed_addend, value))
1356 return bfd_reloc_ok;
1357 else
1358 return bfd_reloc_dangerous;
1361 relocation = value + signed_addend;
1363 relocation -= (input_section->output_section->vma
1364 + input_section->output_offset
1365 + rel->r_offset);
1367 if (! globals->no_pipeline_knowledge)
1369 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
1371 i_ehdrp = elf_elfheader (input_bfd);
1373 /* Previous versions of this code also used to add in the pipline
1374 offset here. This is wrong because the linker is not supposed
1375 to know about such things, and one day it might change. In order
1376 to support old binaries that need the old behaviour however, so
1377 we attempt to detect which ABI was used to create the reloc. */
1378 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1379 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0
1380 || i_ehdrp->e_ident[EI_OSABI] == 0)
1381 relocation += 4;
1384 check = relocation >> howto->rightshift;
1386 /* If this is a signed value, the rightshift just dropped
1387 leading 1 bits (assuming twos complement). */
1388 if ((bfd_signed_vma) relocation >= 0)
1389 signed_check = check;
1390 else
1391 signed_check = check | ~((bfd_vma) -1 >> howto->rightshift);
1393 /* Assumes two's complement. */
1394 if (signed_check > reloc_signed_max || signed_check < reloc_signed_min)
1395 overflow = true;
1397 /* Put RELOCATION back into the insn. */
1398 upper_insn = (upper_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 12) & 0x7ff);
1399 lower_insn = (lower_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 1) & 0x7ff);
1401 /* Put the relocated value back in the object file: */
1402 bfd_put_16 (input_bfd, upper_insn, hit_data);
1403 bfd_put_16 (input_bfd, lower_insn, hit_data + 2);
1405 return (overflow ? bfd_reloc_overflow : bfd_reloc_ok);
1407 break;
1409 case R_ARM_GNU_VTINHERIT:
1410 case R_ARM_GNU_VTENTRY:
1411 return bfd_reloc_ok;
1413 case R_ARM_COPY:
1414 return bfd_reloc_notsupported;
1416 case R_ARM_GLOB_DAT:
1417 return bfd_reloc_notsupported;
1419 case R_ARM_JUMP_SLOT:
1420 return bfd_reloc_notsupported;
1422 case R_ARM_RELATIVE:
1423 return bfd_reloc_notsupported;
1425 case R_ARM_GOTOFF:
1426 /* Relocation is relative to the start of the
1427 global offset table. */
1429 BFD_ASSERT (sgot != NULL);
1430 if (sgot == NULL)
1431 return bfd_reloc_notsupported;
1433 /* Note that sgot->output_offset is not involved in this
1434 calculation. We always want the start of .got. If we
1435 define _GLOBAL_OFFSET_TABLE in a different way, as is
1436 permitted by the ABI, we might have to change this
1437 calculation. */
1439 value -= sgot->output_section->vma;
1440 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1441 contents, rel->r_offset, value,
1442 (bfd_vma) 0);
1444 case R_ARM_GOTPC:
1445 /* Use global offset table as symbol value. */
1447 BFD_ASSERT (sgot != NULL);
1449 if (sgot == NULL)
1450 return bfd_reloc_notsupported;
1452 value = sgot->output_section->vma;
1453 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1454 contents, rel->r_offset, value,
1455 (bfd_vma) 0);
1457 case R_ARM_GOT32:
1458 /* Relocation is to the entry for this symbol in the
1459 global offset table. */
1460 if (sgot == NULL)
1461 return bfd_reloc_notsupported;
1463 if (h != NULL)
1465 bfd_vma off;
1467 off = h->got.offset;
1468 BFD_ASSERT (off != (bfd_vma) -1);
1470 if (!elf_hash_table (info)->dynamic_sections_created ||
1471 (info->shared && (info->symbolic || h->dynindx == -1)
1472 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1474 /* This is actually a static link, or it is a -Bsymbolic link
1475 and the symbol is defined locally. We must initialize this
1476 entry in the global offset table. Since the offset must
1477 always be a multiple of 4, we use the least significant bit
1478 to record whether we have initialized it already.
1480 When doing a dynamic link, we create a .rel.got relocation
1481 entry to initialize the value. This is done in the
1482 finish_dynamic_symbol routine. */
1484 if ((off & 1) != 0)
1485 off &= ~1;
1486 else
1488 bfd_put_32 (output_bfd, value, sgot->contents + off);
1489 h->got.offset |= 1;
1493 value = sgot->output_offset + off;
1495 else
1497 bfd_vma off;
1499 BFD_ASSERT (local_got_offsets != NULL &&
1500 local_got_offsets[r_symndx] != (bfd_vma) -1);
1502 off = local_got_offsets[r_symndx];
1504 /* The offset must always be a multiple of 4. We use the
1505 least significant bit to record whether we have already
1506 generated the necessary reloc. */
1507 if ((off & 1) != 0)
1508 off &= ~1;
1509 else
1511 bfd_put_32 (output_bfd, value, sgot->contents + off);
1513 if (info->shared)
1515 asection * srelgot;
1516 Elf_Internal_Rel outrel;
1518 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
1519 BFD_ASSERT (srelgot != NULL);
1521 outrel.r_offset = (sgot->output_section->vma
1522 + sgot->output_offset
1523 + off);
1524 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1525 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1526 (((Elf32_External_Rel *)
1527 srelgot->contents)
1528 + srelgot->reloc_count));
1529 ++srelgot->reloc_count;
1532 local_got_offsets[r_symndx] |= 1;
1535 value = sgot->output_offset + off;
1538 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1539 contents, rel->r_offset, value,
1540 (bfd_vma) 0);
1542 case R_ARM_PLT32:
1543 /* Relocation is to the entry for this symbol in the
1544 procedure linkage table. */
1546 /* Resolve a PLT32 reloc against a local symbol directly,
1547 without using the procedure linkage table. */
1548 if (h == NULL)
1549 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1550 contents, rel->r_offset, value,
1551 (bfd_vma) 0);
1553 if (h->plt.offset == (bfd_vma) -1)
1554 /* We didn't make a PLT entry for this symbol. This
1555 happens when statically linking PIC code, or when
1556 using -Bsymbolic. */
1557 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1558 contents, rel->r_offset, value,
1559 (bfd_vma) 0);
1561 BFD_ASSERT(splt != NULL);
1562 if (splt == NULL)
1563 return bfd_reloc_notsupported;
1565 value = (splt->output_section->vma
1566 + splt->output_offset
1567 + h->plt.offset);
1568 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1569 contents, rel->r_offset, value,
1570 (bfd_vma) 0);
1572 case R_ARM_SBREL32:
1573 return bfd_reloc_notsupported;
1575 case R_ARM_AMP_VCALL9:
1576 return bfd_reloc_notsupported;
1578 case R_ARM_RSBREL32:
1579 return bfd_reloc_notsupported;
1581 case R_ARM_THM_RPC22:
1582 return bfd_reloc_notsupported;
1584 case R_ARM_RREL32:
1585 return bfd_reloc_notsupported;
1587 case R_ARM_RABS32:
1588 return bfd_reloc_notsupported;
1590 case R_ARM_RPC24:
1591 return bfd_reloc_notsupported;
1593 case R_ARM_RBASE:
1594 return bfd_reloc_notsupported;
1596 default:
1597 return bfd_reloc_notsupported;
1601 #ifdef USE_REL
1602 /* Add INCREMENT to the reloc (of type HOWTO) at ADDRESS. */
1603 static void
1604 arm_add_to_rel (abfd, address, howto, increment)
1605 bfd * abfd;
1606 bfd_byte * address;
1607 reloc_howto_type * howto;
1608 bfd_signed_vma increment;
1610 bfd_vma contents;
1611 bfd_signed_vma addend;
1613 contents = bfd_get_32 (abfd, address);
1615 /* Get the (signed) value from the instruction. */
1616 addend = contents & howto->src_mask;
1617 if (addend & ((howto->src_mask + 1) >> 1))
1619 bfd_signed_vma mask;
1621 mask = -1;
1622 mask &= ~ howto->src_mask;
1623 addend |= mask;
1626 /* Add in the increment, (which is a byte value). */
1627 switch (howto->type)
1629 case R_ARM_THM_PC22:
1630 default:
1631 addend += increment;
1632 break;
1634 case R_ARM_PC24:
1635 addend <<= howto->size;
1636 addend += increment;
1638 /* Should we check for overflow here ? */
1640 /* Drop any undesired bits. */
1641 addend >>= howto->rightshift;
1642 break;
1645 contents = (contents & ~ howto->dst_mask) | (addend & howto->dst_mask);
1647 bfd_put_32 (abfd, contents, address);
1649 #endif /* USE_REL */
1651 /* Relocate an ARM ELF section. */
1652 static boolean
1653 elf32_arm_relocate_section (output_bfd, info, input_bfd, input_section,
1654 contents, relocs, local_syms, local_sections)
1655 bfd * output_bfd;
1656 struct bfd_link_info * info;
1657 bfd * input_bfd;
1658 asection * input_section;
1659 bfd_byte * contents;
1660 Elf_Internal_Rela * relocs;
1661 Elf_Internal_Sym * local_syms;
1662 asection ** local_sections;
1664 Elf_Internal_Shdr * symtab_hdr;
1665 struct elf_link_hash_entry ** sym_hashes;
1666 Elf_Internal_Rela * rel;
1667 Elf_Internal_Rela * relend;
1668 const char * name;
1670 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1671 sym_hashes = elf_sym_hashes (input_bfd);
1673 rel = relocs;
1674 relend = relocs + input_section->reloc_count;
1675 for (; rel < relend; rel++)
1677 int r_type;
1678 reloc_howto_type * howto;
1679 unsigned long r_symndx;
1680 Elf_Internal_Sym * sym;
1681 asection * sec;
1682 struct elf_link_hash_entry * h;
1683 bfd_vma relocation;
1684 bfd_reloc_status_type r;
1685 arelent bfd_reloc;
1687 r_symndx = ELF32_R_SYM (rel->r_info);
1688 r_type = ELF32_R_TYPE (rel->r_info);
1690 if ( r_type == R_ARM_GNU_VTENTRY
1691 || r_type == R_ARM_GNU_VTINHERIT)
1692 continue;
1694 elf32_arm_info_to_howto (input_bfd, & bfd_reloc, rel);
1695 howto = bfd_reloc.howto;
1697 if (info->relocateable)
1699 /* This is a relocateable link. We don't have to change
1700 anything, unless the reloc is against a section symbol,
1701 in which case we have to adjust according to where the
1702 section symbol winds up in the output section. */
1703 if (r_symndx < symtab_hdr->sh_info)
1705 sym = local_syms + r_symndx;
1706 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1708 sec = local_sections[r_symndx];
1709 #ifdef USE_REL
1710 arm_add_to_rel (input_bfd, contents + rel->r_offset,
1711 howto, sec->output_offset + sym->st_value);
1712 #else
1713 rel->r_addend += (sec->output_offset + sym->st_value)
1714 >> howto->rightshift;
1715 #endif
1719 continue;
1722 /* This is a final link. */
1723 h = NULL;
1724 sym = NULL;
1725 sec = NULL;
1726 if (r_symndx < symtab_hdr->sh_info)
1728 sym = local_syms + r_symndx;
1729 sec = local_sections[r_symndx];
1730 relocation = (sec->output_section->vma
1731 + sec->output_offset
1732 + sym->st_value);
1734 else
1736 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1737 while (h->root.type == bfd_link_hash_indirect
1738 || h->root.type == bfd_link_hash_warning)
1739 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1740 if (h->root.type == bfd_link_hash_defined
1741 || h->root.type == bfd_link_hash_defweak)
1743 int relocation_needed = 1;
1745 sec = h->root.u.def.section;
1747 /* In these cases, we don't need the relocation value.
1748 We check specially because in some obscure cases
1749 sec->output_section will be NULL. */
1750 switch (r_type)
1752 case R_ARM_PC24:
1753 case R_ARM_ABS32:
1754 if (info->shared
1755 && (
1756 (!info->symbolic && h->dynindx != -1)
1757 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1759 && ((input_section->flags & SEC_ALLOC) != 0)
1761 relocation_needed = 0;
1762 break;
1764 case R_ARM_GOTPC:
1765 relocation_needed = 0;
1766 break;
1768 case R_ARM_GOT32:
1769 if (elf_hash_table(info)->dynamic_sections_created
1770 && (!info->shared
1771 || (!info->symbolic && h->dynindx != -1)
1772 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1775 relocation_needed = 0;
1776 break;
1778 case R_ARM_PLT32:
1779 if (h->plt.offset != (bfd_vma)-1)
1780 relocation_needed = 0;
1781 break;
1783 default:
1784 if (sec->output_section == NULL)
1786 (*_bfd_error_handler)
1787 (_("%s: warning: unresolvable relocation against symbol `%s' from %s section"),
1788 bfd_get_filename (input_bfd), h->root.root.string,
1789 bfd_get_section_name (input_bfd, input_section));
1790 relocation_needed = 0;
1794 if (relocation_needed)
1795 relocation = h->root.u.def.value
1796 + sec->output_section->vma
1797 + sec->output_offset;
1798 else
1799 relocation = 0;
1801 else if (h->root.type == bfd_link_hash_undefweak)
1802 relocation = 0;
1803 else if (info->shared && !info->symbolic && !info->no_undefined)
1804 relocation = 0;
1805 else
1807 if (!((*info->callbacks->undefined_symbol)
1808 (info, h->root.root.string, input_bfd,
1809 input_section, rel->r_offset,
1810 (!info->shared || info->no_undefined))))
1811 return false;
1812 relocation = 0;
1816 if (h != NULL)
1817 name = h->root.root.string;
1818 else
1820 name = (bfd_elf_string_from_elf_section
1821 (input_bfd, symtab_hdr->sh_link, sym->st_name));
1822 if (name == NULL || *name == '\0')
1823 name = bfd_section_name (input_bfd, sec);
1826 r = elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
1827 input_section, contents, rel,
1828 relocation, info, sec, name,
1829 (h ? ELF_ST_TYPE (h->type) :
1830 ELF_ST_TYPE (sym->st_info)), h);
1832 if (r != bfd_reloc_ok)
1834 const char * msg = (const char *) 0;
1836 switch (r)
1838 case bfd_reloc_overflow:
1839 if (!((*info->callbacks->reloc_overflow)
1840 (info, name, howto->name, (bfd_vma) 0,
1841 input_bfd, input_section, rel->r_offset)))
1842 return false;
1843 break;
1845 case bfd_reloc_undefined:
1846 if (!((*info->callbacks->undefined_symbol)
1847 (info, name, input_bfd, input_section,
1848 rel->r_offset, true)))
1849 return false;
1850 break;
1852 case bfd_reloc_outofrange:
1853 msg = _ ("internal error: out of range error");
1854 goto common_error;
1856 case bfd_reloc_notsupported:
1857 msg = _ ("internal error: unsupported relocation error");
1858 goto common_error;
1860 case bfd_reloc_dangerous:
1861 msg = _ ("internal error: dangerous error");
1862 goto common_error;
1864 default:
1865 msg = _ ("internal error: unknown error");
1866 /* fall through */
1868 common_error:
1869 if (!((*info->callbacks->warning)
1870 (info, msg, name, input_bfd, input_section,
1871 rel->r_offset)))
1872 return false;
1873 break;
1878 return true;
1881 /* Function to keep ARM specific flags in the ELF header. */
1882 static boolean
1883 elf32_arm_set_private_flags (abfd, flags)
1884 bfd *abfd;
1885 flagword flags;
1887 if (elf_flags_init (abfd)
1888 && elf_elfheader (abfd)->e_flags != flags)
1890 if (flags & EF_INTERWORK)
1891 _bfd_error_handler (_ ("\
1892 Warning: Not setting interwork flag of %s since it has already been specified as non-interworking"),
1893 bfd_get_filename (abfd));
1894 else
1895 _bfd_error_handler (_ ("\
1896 Warning: Clearing the interwork flag of %s due to outside request"),
1897 bfd_get_filename (abfd));
1899 else
1901 elf_elfheader (abfd)->e_flags = flags;
1902 elf_flags_init (abfd) = true;
1905 return true;
1908 /* Copy backend specific data from one object module to another */
1909 static boolean
1910 elf32_arm_copy_private_bfd_data (ibfd, obfd)
1911 bfd *ibfd;
1912 bfd *obfd;
1914 flagword in_flags;
1915 flagword out_flags;
1917 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
1918 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
1919 return true;
1921 in_flags = elf_elfheader (ibfd)->e_flags;
1922 out_flags = elf_elfheader (obfd)->e_flags;
1924 if (elf_flags_init (obfd) && in_flags != out_flags)
1926 /* Cannot mix PIC and non-PIC code. */
1927 if ((in_flags & EF_PIC) != (out_flags & EF_PIC))
1928 return false;
1930 /* Cannot mix APCS26 and APCS32 code. */
1931 if ((in_flags & EF_APCS_26) != (out_flags & EF_APCS_26))
1932 return false;
1934 /* Cannot mix float APCS and non-float APCS code. */
1935 if ((in_flags & EF_APCS_FLOAT) != (out_flags & EF_APCS_FLOAT))
1936 return false;
1938 /* If the src and dest have different interworking flags
1939 then turn off the interworking bit. */
1940 if ((in_flags & EF_INTERWORK) != (out_flags & EF_INTERWORK))
1942 if (out_flags & EF_INTERWORK)
1943 _bfd_error_handler (_ ("\
1944 Warning: Clearing the interwork flag in %s because non-interworking code in %s has been linked with it"),
1945 bfd_get_filename (obfd), bfd_get_filename (ibfd));
1947 in_flags &= ~EF_INTERWORK;
1951 elf_elfheader (obfd)->e_flags = in_flags;
1952 elf_flags_init (obfd) = true;
1954 return true;
1957 /* Merge backend specific data from an object file to the output
1958 object file when linking. */
1959 static boolean
1960 elf32_arm_merge_private_bfd_data (ibfd, obfd)
1961 bfd *ibfd;
1962 bfd *obfd;
1964 flagword out_flags;
1965 flagword in_flags;
1967 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
1968 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
1969 return true;
1971 /* Check if we have the same endianess */
1972 if ( ibfd->xvec->byteorder != obfd->xvec->byteorder
1973 && obfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN
1974 && ibfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
1976 (*_bfd_error_handler)
1977 (_("%s: compiled for a %s endian system and target is %s endian"),
1978 bfd_get_filename (ibfd),
1979 bfd_big_endian (ibfd) ? "big" : "little",
1980 bfd_big_endian (obfd) ? "big" : "little");
1982 bfd_set_error (bfd_error_wrong_format);
1983 return false;
1986 /* The input BFD must have had its flags initialised. */
1987 /* The following seems bogus to me -- The flags are initialized in
1988 the assembler but I don't think an elf_flags_init field is
1989 written into the object */
1990 /* BFD_ASSERT (elf_flags_init (ibfd)); */
1992 in_flags = elf_elfheader (ibfd)->e_flags;
1993 out_flags = elf_elfheader (obfd)->e_flags;
1995 if (!elf_flags_init (obfd))
1997 /* If the input is the default architecture then do not
1998 bother setting the flags for the output architecture,
1999 instead allow future merges to do this. If no future
2000 merges ever set these flags then they will retain their
2001 unitialised values, which surprise surprise, correspond
2002 to the default values. */
2003 if (bfd_get_arch_info (ibfd)->the_default)
2004 return true;
2006 elf_flags_init (obfd) = true;
2007 elf_elfheader (obfd)->e_flags = in_flags;
2009 if (bfd_get_arch (obfd) == bfd_get_arch (ibfd)
2010 && bfd_get_arch_info (obfd)->the_default)
2011 return bfd_set_arch_mach (obfd, bfd_get_arch (ibfd), bfd_get_mach (ibfd));
2013 return true;
2016 /* Check flag compatibility. */
2017 if (in_flags == out_flags)
2018 return true;
2020 /* Complain about various flag mismatches. */
2022 if ((in_flags & EF_APCS_26) != (out_flags & EF_APCS_26))
2023 _bfd_error_handler (_ ("\
2024 Error: %s compiled for APCS-%d, whereas %s is compiled for APCS-%d"),
2025 bfd_get_filename (ibfd),
2026 in_flags & EF_APCS_26 ? 26 : 32,
2027 bfd_get_filename (obfd),
2028 out_flags & EF_APCS_26 ? 26 : 32);
2030 if ((in_flags & EF_APCS_FLOAT) != (out_flags & EF_APCS_FLOAT))
2031 _bfd_error_handler (_ ("\
2032 Error: %s passes floats in %s registers, whereas %s passes them in %s registers"),
2033 bfd_get_filename (ibfd),
2034 in_flags & EF_APCS_FLOAT ? _ ("float") : _ ("integer"),
2035 bfd_get_filename (obfd),
2036 out_flags & EF_APCS_26 ? _ ("float") : _ ("integer"));
2038 if ((in_flags & EF_PIC) != (out_flags & EF_PIC))
2039 _bfd_error_handler (_ ("\
2040 Error: %s is compiled as position %s code, whereas %s is not"),
2041 bfd_get_filename (ibfd),
2042 in_flags & EF_PIC ? _ ("independent") : _ ("dependent"),
2043 bfd_get_filename (obfd));
2045 /* Interworking mismatch is only a warning. */
2046 if ((in_flags & EF_INTERWORK) != (out_flags & EF_INTERWORK))
2048 _bfd_error_handler (_ ("\
2049 Warning: %s %s interworking, whereas %s %s"),
2050 bfd_get_filename (ibfd),
2051 in_flags & EF_INTERWORK ? _ ("supports") : _ ("does not support"),
2052 bfd_get_filename (obfd),
2053 out_flags & EF_INTERWORK ? _ ("does not") : _ ("does"));
2054 return true;
2057 return false;
2060 /* Display the flags field */
2061 static boolean
2062 elf32_arm_print_private_bfd_data (abfd, ptr)
2063 bfd *abfd;
2064 PTR ptr;
2066 FILE *file = (FILE *) ptr;
2068 BFD_ASSERT (abfd != NULL && ptr != NULL);
2070 /* Print normal ELF private data. */
2071 _bfd_elf_print_private_bfd_data (abfd, ptr);
2073 /* Ignore init flag - it may not be set, despite the flags field containing valid data. */
2075 /* xgettext:c-format */
2076 fprintf (file, _ ("private flags = %lx:"), elf_elfheader (abfd)->e_flags);
2078 if (elf_elfheader (abfd)->e_flags & EF_INTERWORK)
2079 fprintf (file, _ (" [interworking enabled]"));
2080 else
2081 fprintf (file, _ (" [interworking not enabled]"));
2083 if (elf_elfheader (abfd)->e_flags & EF_APCS_26)
2084 fprintf (file, _ (" [APCS-26]"));
2085 else
2086 fprintf (file, _ (" [APCS-32]"));
2088 if (elf_elfheader (abfd)->e_flags & EF_APCS_FLOAT)
2089 fprintf (file, _ (" [floats passed in float registers]"));
2090 else
2091 fprintf (file, _ (" [floats passed in integer registers]"));
2093 if (elf_elfheader (abfd)->e_flags & EF_PIC)
2094 fprintf (file, _ (" [position independent]"));
2095 else
2096 fprintf (file, _ (" [absolute position]"));
2098 fputc ('\n', file);
2100 return true;
2103 static int
2104 elf32_arm_get_symbol_type (elf_sym, type)
2105 Elf_Internal_Sym * elf_sym;
2106 int type;
2108 switch (ELF_ST_TYPE (elf_sym->st_info))
2110 case STT_ARM_TFUNC:
2111 return ELF_ST_TYPE (elf_sym->st_info);
2112 break;
2113 case STT_ARM_16BIT:
2114 /* If the symbol is not an object, return the STT_ARM_16BIT flag.
2115 This allows us to distinguish between data used by Thumb instructions
2116 and non-data (which is probably code) inside Thumb regions of an
2117 executable. */
2118 if (type != STT_OBJECT)
2119 return ELF_ST_TYPE (elf_sym->st_info);
2120 break;
2123 return type;
2126 static asection *
2127 elf32_arm_gc_mark_hook (abfd, info, rel, h, sym)
2128 bfd *abfd;
2129 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2130 Elf_Internal_Rela *rel;
2131 struct elf_link_hash_entry *h;
2132 Elf_Internal_Sym *sym;
2134 if (h != NULL)
2136 switch (ELF32_R_TYPE (rel->r_info))
2138 case R_ARM_GNU_VTINHERIT:
2139 case R_ARM_GNU_VTENTRY:
2140 break;
2142 default:
2143 switch (h->root.type)
2145 case bfd_link_hash_defined:
2146 case bfd_link_hash_defweak:
2147 return h->root.u.def.section;
2149 case bfd_link_hash_common:
2150 return h->root.u.c.p->section;
2152 default:
2153 break;
2157 else
2159 if (!(elf_bad_symtab (abfd)
2160 && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
2161 && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
2162 && sym->st_shndx != SHN_COMMON))
2164 return bfd_section_from_elf_index (abfd, sym->st_shndx);
2167 return NULL;
2170 /* Update the got entry reference counts for the section being removed. */
2172 static boolean
2173 elf32_arm_gc_sweep_hook (abfd, info, sec, relocs)
2174 bfd *abfd ATTRIBUTE_UNUSED;
2175 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2176 asection *sec ATTRIBUTE_UNUSED;
2177 const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
2179 /* We don't support garbage collection of GOT and PLT relocs yet. */
2180 return true;
2183 /* Look through the relocs for a section during the first phase. */
2185 static boolean
2186 elf32_arm_check_relocs (abfd, info, sec, relocs)
2187 bfd * abfd;
2188 struct bfd_link_info * info;
2189 asection * sec;
2190 const Elf_Internal_Rela * relocs;
2192 Elf_Internal_Shdr * symtab_hdr;
2193 struct elf_link_hash_entry ** sym_hashes;
2194 struct elf_link_hash_entry ** sym_hashes_end;
2195 const Elf_Internal_Rela * rel;
2196 const Elf_Internal_Rela * rel_end;
2197 bfd * dynobj;
2198 asection * sgot, *srelgot, *sreloc;
2199 bfd_vma * local_got_offsets;
2201 if (info->relocateable)
2202 return true;
2204 sgot = srelgot = sreloc = NULL;
2206 dynobj = elf_hash_table (info)->dynobj;
2207 local_got_offsets = elf_local_got_offsets (abfd);
2209 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2210 sym_hashes = elf_sym_hashes (abfd);
2211 sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof(Elf32_External_Sym);
2212 if (!elf_bad_symtab (abfd))
2213 sym_hashes_end -= symtab_hdr->sh_info;
2215 rel_end = relocs + sec->reloc_count;
2216 for (rel = relocs; rel < rel_end; rel++)
2218 struct elf_link_hash_entry *h;
2219 unsigned long r_symndx;
2221 r_symndx = ELF32_R_SYM (rel->r_info);
2222 if (r_symndx < symtab_hdr->sh_info)
2223 h = NULL;
2224 else
2225 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
2227 /* Some relocs require a global offset table. */
2228 if (dynobj == NULL)
2230 switch (ELF32_R_TYPE (rel->r_info))
2232 case R_ARM_GOT32:
2233 case R_ARM_GOTOFF:
2234 case R_ARM_GOTPC:
2235 elf_hash_table (info)->dynobj = dynobj = abfd;
2236 if (! _bfd_elf_create_got_section (dynobj, info))
2237 return false;
2238 break;
2240 default:
2241 break;
2245 switch (ELF32_R_TYPE (rel->r_info))
2247 case R_ARM_GOT32:
2248 /* This symbol requires a global offset table entry. */
2249 if (sgot == NULL)
2251 sgot = bfd_get_section_by_name (dynobj, ".got");
2252 BFD_ASSERT (sgot != NULL);
2255 /* Get the got relocation section if necessary. */
2256 if (srelgot == NULL
2257 && (h != NULL || info->shared))
2259 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
2261 /* If no got relocation section, make one and initialize. */
2262 if (srelgot == NULL)
2264 srelgot = bfd_make_section (dynobj, ".rel.got");
2265 if (srelgot == NULL
2266 || ! bfd_set_section_flags (dynobj, srelgot,
2267 (SEC_ALLOC
2268 | SEC_LOAD
2269 | SEC_HAS_CONTENTS
2270 | SEC_IN_MEMORY
2271 | SEC_LINKER_CREATED
2272 | SEC_READONLY))
2273 || ! bfd_set_section_alignment (dynobj, srelgot, 2))
2274 return false;
2278 if (h != NULL)
2280 if (h->got.offset != (bfd_vma) -1)
2281 /* We have already allocated space in the .got. */
2282 break;
2284 h->got.offset = sgot->_raw_size;
2286 /* Make sure this symbol is output as a dynamic symbol. */
2287 if (h->dynindx == -1)
2288 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2289 return false;
2291 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2293 else
2295 /* This is a global offset table entry for a local
2296 symbol. */
2297 if (local_got_offsets == NULL)
2299 size_t size;
2300 register unsigned int i;
2302 size = symtab_hdr->sh_info * sizeof (bfd_vma);
2303 local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
2304 if (local_got_offsets == NULL)
2305 return false;
2306 elf_local_got_offsets (abfd) = local_got_offsets;
2307 for (i = 0; i < symtab_hdr->sh_info; i++)
2308 local_got_offsets[i] = (bfd_vma) -1;
2311 if (local_got_offsets[r_symndx] != (bfd_vma) -1)
2312 /* We have already allocated space in the .got. */
2313 break;
2315 local_got_offsets[r_symndx] = sgot->_raw_size;
2317 if (info->shared)
2318 /* If we are generating a shared object, we need to
2319 output a R_ARM_RELATIVE reloc so that the dynamic
2320 linker can adjust this GOT entry. */
2321 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2324 sgot->_raw_size += 4;
2325 break;
2327 case R_ARM_PLT32:
2328 /* This symbol requires a procedure linkage table entry. We
2329 actually build the entry in adjust_dynamic_symbol,
2330 because this might be a case of linking PIC code which is
2331 never referenced by a dynamic object, in which case we
2332 don't need to generate a procedure linkage table entry
2333 after all. */
2335 /* If this is a local symbol, we resolve it directly without
2336 creating a procedure linkage table entry. */
2337 if (h == NULL)
2338 continue;
2340 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
2341 break;
2343 case R_ARM_ABS32:
2344 case R_ARM_REL32:
2345 case R_ARM_PC24:
2346 /* If we are creating a shared library, and this is a reloc
2347 against a global symbol, or a non PC relative reloc
2348 against a local symbol, then we need to copy the reloc
2349 into the shared library. However, if we are linking with
2350 -Bsymbolic, we do not need to copy a reloc against a
2351 global symbol which is defined in an object we are
2352 including in the link (i.e., DEF_REGULAR is set). At
2353 this point we have not seen all the input files, so it is
2354 possible that DEF_REGULAR is not set now but will be set
2355 later (it is never cleared). We account for that
2356 possibility below by storing information in the
2357 pcrel_relocs_copied field of the hash table entry. */
2358 if (info->shared
2359 && (ELF32_R_TYPE (rel->r_info) != R_ARM_PC24
2360 || (h != NULL
2361 && (! info->symbolic
2362 || (h->elf_link_hash_flags
2363 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
2365 /* When creating a shared object, we must copy these
2366 reloc types into the output file. We create a reloc
2367 section in dynobj and make room for this reloc. */
2368 if (sreloc == NULL)
2370 const char * name;
2372 name = (bfd_elf_string_from_elf_section
2373 (abfd,
2374 elf_elfheader (abfd)->e_shstrndx,
2375 elf_section_data (sec)->rel_hdr.sh_name));
2376 if (name == NULL)
2377 return false;
2379 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
2380 && strcmp (bfd_get_section_name (abfd, sec),
2381 name + 4) == 0);
2383 sreloc = bfd_get_section_by_name (dynobj, name);
2384 if (sreloc == NULL)
2386 flagword flags;
2388 sreloc = bfd_make_section (dynobj, name);
2389 flags = (SEC_HAS_CONTENTS | SEC_READONLY
2390 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2391 if ((sec->flags & SEC_ALLOC) != 0)
2392 flags |= SEC_ALLOC | SEC_LOAD;
2393 if (sreloc == NULL
2394 || ! bfd_set_section_flags (dynobj, sreloc, flags)
2395 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
2396 return false;
2400 sreloc->_raw_size += sizeof (Elf32_External_Rel);
2401 /* If we are linking with -Bsymbolic, and this is a
2402 global symbol, we count the number of PC relative
2403 relocations we have entered for this symbol, so that
2404 we can discard them again if the symbol is later
2405 defined by a regular object. Note that this function
2406 is only called if we are using an elf_i386 linker
2407 hash table, which means that h is really a pointer to
2408 an elf_i386_link_hash_entry. */
2409 if (h != NULL && info->symbolic
2410 && ELF32_R_TYPE (rel->r_info) == R_ARM_PC24)
2412 struct elf32_arm_link_hash_entry * eh;
2413 struct elf32_arm_pcrel_relocs_copied * p;
2415 eh = (struct elf32_arm_link_hash_entry *) h;
2417 for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
2418 if (p->section == sreloc)
2419 break;
2421 if (p == NULL)
2423 p = ((struct elf32_arm_pcrel_relocs_copied *)
2424 bfd_alloc (dynobj, sizeof * p));
2426 if (p == NULL)
2427 return false;
2428 p->next = eh->pcrel_relocs_copied;
2429 eh->pcrel_relocs_copied = p;
2430 p->section = sreloc;
2431 p->count = 0;
2434 ++p->count;
2437 break;
2439 /* This relocation describes the C++ object vtable hierarchy.
2440 Reconstruct it for later use during GC. */
2441 case R_ARM_GNU_VTINHERIT:
2442 if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
2443 return false;
2444 break;
2446 /* This relocation describes which C++ vtable entries are actually
2447 used. Record for later use during GC. */
2448 case R_ARM_GNU_VTENTRY:
2449 if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_offset))
2450 return false;
2451 break;
2455 return true;
2459 /* Find the nearest line to a particular section and offset, for error
2460 reporting. This code is a duplicate of the code in elf.c, except
2461 that it also accepts STT_ARM_TFUNC as a symbol that names a function. */
2463 static boolean
2464 elf32_arm_find_nearest_line
2465 (abfd, section, symbols, offset, filename_ptr, functionname_ptr, line_ptr)
2466 bfd * abfd;
2467 asection * section;
2468 asymbol ** symbols;
2469 bfd_vma offset;
2470 CONST char ** filename_ptr;
2471 CONST char ** functionname_ptr;
2472 unsigned int * line_ptr;
2474 boolean found;
2475 const char * filename;
2476 asymbol * func;
2477 bfd_vma low_func;
2478 asymbol ** p;
2480 if (_bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
2481 filename_ptr, functionname_ptr,
2482 line_ptr, 0))
2483 return true;
2485 if (! _bfd_stab_section_find_nearest_line (abfd, symbols, section, offset,
2486 &found, filename_ptr,
2487 functionname_ptr, line_ptr,
2488 &elf_tdata (abfd)->line_info))
2489 return false;
2491 if (found)
2492 return true;
2494 if (symbols == NULL)
2495 return false;
2497 filename = NULL;
2498 func = NULL;
2499 low_func = 0;
2501 for (p = symbols; *p != NULL; p++)
2503 elf_symbol_type *q;
2505 q = (elf_symbol_type *) *p;
2507 if (bfd_get_section (&q->symbol) != section)
2508 continue;
2510 switch (ELF_ST_TYPE (q->internal_elf_sym.st_info))
2512 default:
2513 break;
2514 case STT_FILE:
2515 filename = bfd_asymbol_name (&q->symbol);
2516 break;
2517 case STT_NOTYPE:
2518 case STT_FUNC:
2519 case STT_ARM_TFUNC:
2520 if (q->symbol.section == section
2521 && q->symbol.value >= low_func
2522 && q->symbol.value <= offset)
2524 func = (asymbol *) q;
2525 low_func = q->symbol.value;
2527 break;
2531 if (func == NULL)
2532 return false;
2534 *filename_ptr = filename;
2535 *functionname_ptr = bfd_asymbol_name (func);
2536 *line_ptr = 0;
2538 return true;
2541 /* Adjust a symbol defined by a dynamic object and referenced by a
2542 regular object. The current definition is in some section of the
2543 dynamic object, but we're not including those sections. We have to
2544 change the definition to something the rest of the link can
2545 understand. */
2547 static boolean
2548 elf32_arm_adjust_dynamic_symbol (info, h)
2549 struct bfd_link_info * info;
2550 struct elf_link_hash_entry * h;
2552 bfd * dynobj;
2553 asection * s;
2554 unsigned int power_of_two;
2556 dynobj = elf_hash_table (info)->dynobj;
2558 /* Make sure we know what is going on here. */
2559 BFD_ASSERT (dynobj != NULL
2560 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
2561 || h->weakdef != NULL
2562 || ((h->elf_link_hash_flags
2563 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2564 && (h->elf_link_hash_flags
2565 & ELF_LINK_HASH_REF_REGULAR) != 0
2566 && (h->elf_link_hash_flags
2567 & ELF_LINK_HASH_DEF_REGULAR) == 0)));
2569 /* If this is a function, put it in the procedure linkage table. We
2570 will fill in the contents of the procedure linkage table later,
2571 when we know the address of the .got section. */
2572 if (h->type == STT_FUNC
2573 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
2575 if (! info->shared
2576 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2577 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
2579 /* This case can occur if we saw a PLT32 reloc in an input
2580 file, but the symbol was never referred to by a dynamic
2581 object. In such a case, we don't actually need to build
2582 a procedure linkage table, and we can just do a PC32
2583 reloc instead. */
2584 BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
2585 return true;
2588 /* Make sure this symbol is output as a dynamic symbol. */
2589 if (h->dynindx == -1)
2591 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2592 return false;
2595 s = bfd_get_section_by_name (dynobj, ".plt");
2596 BFD_ASSERT (s != NULL);
2598 /* If this is the first .plt entry, make room for the special
2599 first entry. */
2600 if (s->_raw_size == 0)
2601 s->_raw_size += PLT_ENTRY_SIZE;
2603 /* If this symbol is not defined in a regular file, and we are
2604 not generating a shared library, then set the symbol to this
2605 location in the .plt. This is required to make function
2606 pointers compare as equal between the normal executable and
2607 the shared library. */
2608 if (! info->shared
2609 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2611 h->root.u.def.section = s;
2612 h->root.u.def.value = s->_raw_size;
2615 h->plt.offset = s->_raw_size;
2617 /* Make room for this entry. */
2618 s->_raw_size += PLT_ENTRY_SIZE;
2620 /* We also need to make an entry in the .got.plt section, which
2621 will be placed in the .got section by the linker script. */
2623 s = bfd_get_section_by_name (dynobj, ".got.plt");
2624 BFD_ASSERT (s != NULL);
2625 s->_raw_size += 4;
2627 /* We also need to make an entry in the .rel.plt section. */
2629 s = bfd_get_section_by_name (dynobj, ".rel.plt");
2630 BFD_ASSERT (s != NULL);
2631 s->_raw_size += sizeof (Elf32_External_Rel);
2633 return true;
2636 /* If this is a weak symbol, and there is a real definition, the
2637 processor independent code will have arranged for us to see the
2638 real definition first, and we can just use the same value. */
2639 if (h->weakdef != NULL)
2641 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
2642 || h->weakdef->root.type == bfd_link_hash_defweak);
2643 h->root.u.def.section = h->weakdef->root.u.def.section;
2644 h->root.u.def.value = h->weakdef->root.u.def.value;
2645 return true;
2648 /* This is a reference to a symbol defined by a dynamic object which
2649 is not a function. */
2651 /* If we are creating a shared library, we must presume that the
2652 only references to the symbol are via the global offset table.
2653 For such cases we need not do anything here; the relocations will
2654 be handled correctly by relocate_section. */
2655 if (info->shared)
2656 return true;
2658 /* We must allocate the symbol in our .dynbss section, which will
2659 become part of the .bss section of the executable. There will be
2660 an entry for this symbol in the .dynsym section. The dynamic
2661 object will contain position independent code, so all references
2662 from the dynamic object to this symbol will go through the global
2663 offset table. The dynamic linker will use the .dynsym entry to
2664 determine the address it must put in the global offset table, so
2665 both the dynamic object and the regular object will refer to the
2666 same memory location for the variable. */
2668 s = bfd_get_section_by_name (dynobj, ".dynbss");
2669 BFD_ASSERT (s != NULL);
2671 /* We must generate a R_ARM_COPY reloc to tell the dynamic linker to
2672 copy the initial value out of the dynamic object and into the
2673 runtime process image. We need to remember the offset into the
2674 .rel.bss section we are going to use. */
2675 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
2677 asection *srel;
2679 srel = bfd_get_section_by_name (dynobj, ".rel.bss");
2680 BFD_ASSERT (srel != NULL);
2681 srel->_raw_size += sizeof (Elf32_External_Rel);
2682 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
2685 /* We need to figure out the alignment required for this symbol. I
2686 have no idea how ELF linkers handle this. */
2687 power_of_two = bfd_log2 (h->size);
2688 if (power_of_two > 3)
2689 power_of_two = 3;
2691 /* Apply the required alignment. */
2692 s->_raw_size = BFD_ALIGN (s->_raw_size,
2693 (bfd_size_type) (1 << power_of_two));
2694 if (power_of_two > bfd_get_section_alignment (dynobj, s))
2696 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
2697 return false;
2700 /* Define the symbol as being at this point in the section. */
2701 h->root.u.def.section = s;
2702 h->root.u.def.value = s->_raw_size;
2704 /* Increment the section size to make room for the symbol. */
2705 s->_raw_size += h->size;
2707 return true;
2710 /* Set the sizes of the dynamic sections. */
2712 static boolean
2713 elf32_arm_size_dynamic_sections (output_bfd, info)
2714 bfd * output_bfd;
2715 struct bfd_link_info * info;
2717 bfd * dynobj;
2718 asection * s;
2719 boolean plt;
2720 boolean relocs;
2721 boolean reltext;
2723 dynobj = elf_hash_table (info)->dynobj;
2724 BFD_ASSERT (dynobj != NULL);
2726 if (elf_hash_table (info)->dynamic_sections_created)
2728 /* Set the contents of the .interp section to the interpreter. */
2729 if (! info->shared)
2731 s = bfd_get_section_by_name (dynobj, ".interp");
2732 BFD_ASSERT (s != NULL);
2733 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
2734 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
2737 else
2739 /* We may have created entries in the .rel.got section.
2740 However, if we are not creating the dynamic sections, we will
2741 not actually use these entries. Reset the size of .rel.got,
2742 which will cause it to get stripped from the output file
2743 below. */
2744 s = bfd_get_section_by_name (dynobj, ".rel.got");
2745 if (s != NULL)
2746 s->_raw_size = 0;
2749 /* If this is a -Bsymbolic shared link, then we need to discard all
2750 PC relative relocs against symbols defined in a regular object.
2751 We allocated space for them in the check_relocs routine, but we
2752 will not fill them in in the relocate_section routine. */
2753 if (info->shared && info->symbolic)
2754 elf32_arm_link_hash_traverse (elf32_arm_hash_table (info),
2755 elf32_arm_discard_copies,
2756 (PTR) NULL);
2758 /* The check_relocs and adjust_dynamic_symbol entry points have
2759 determined the sizes of the various dynamic sections. Allocate
2760 memory for them. */
2761 plt = false;
2762 relocs = false;
2763 reltext = false;
2764 for (s = dynobj->sections; s != NULL; s = s->next)
2766 const char * name;
2767 boolean strip;
2769 if ((s->flags & SEC_LINKER_CREATED) == 0)
2770 continue;
2772 /* It's OK to base decisions on the section name, because none
2773 of the dynobj section names depend upon the input files. */
2774 name = bfd_get_section_name (dynobj, s);
2776 strip = false;
2778 if (strcmp (name, ".plt") == 0)
2780 if (s->_raw_size == 0)
2782 /* Strip this section if we don't need it; see the
2783 comment below. */
2784 strip = true;
2786 else
2788 /* Remember whether there is a PLT. */
2789 plt = true;
2792 else if (strncmp (name, ".rel", 4) == 0)
2794 if (s->_raw_size == 0)
2796 /* If we don't need this section, strip it from the
2797 output file. This is mostly to handle .rel.bss and
2798 .rel.plt. We must create both sections in
2799 create_dynamic_sections, because they must be created
2800 before the linker maps input sections to output
2801 sections. The linker does that before
2802 adjust_dynamic_symbol is called, and it is that
2803 function which decides whether anything needs to go
2804 into these sections. */
2805 strip = true;
2807 else
2809 asection * target;
2811 /* Remember whether there are any reloc sections other
2812 than .rel.plt. */
2813 if (strcmp (name, ".rel.plt") != 0)
2815 const char *outname;
2817 relocs = true;
2819 /* If this relocation section applies to a read only
2820 section, then we probably need a DT_TEXTREL
2821 entry. The entries in the .rel.plt section
2822 really apply to the .got section, which we
2823 created ourselves and so know is not readonly. */
2824 outname = bfd_get_section_name (output_bfd,
2825 s->output_section);
2826 target = bfd_get_section_by_name (output_bfd, outname + 4);
2828 if (target != NULL
2829 && (target->flags & SEC_READONLY) != 0
2830 && (target->flags & SEC_ALLOC) != 0)
2831 reltext = true;
2834 /* We use the reloc_count field as a counter if we need
2835 to copy relocs into the output file. */
2836 s->reloc_count = 0;
2839 else if (strncmp (name, ".got", 4) != 0)
2841 /* It's not one of our sections, so don't allocate space. */
2842 continue;
2845 if (strip)
2847 asection ** spp;
2849 for (spp = &s->output_section->owner->sections;
2850 *spp != s->output_section;
2851 spp = &(*spp)->next)
2853 *spp = s->output_section->next;
2854 --s->output_section->owner->section_count;
2856 continue;
2859 /* Allocate memory for the section contents. */
2860 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
2861 if (s->contents == NULL && s->_raw_size != 0)
2862 return false;
2865 if (elf_hash_table (info)->dynamic_sections_created)
2867 /* Add some entries to the .dynamic section. We fill in the
2868 values later, in elf32_arm_finish_dynamic_sections, but we
2869 must add the entries now so that we get the correct size for
2870 the .dynamic section. The DT_DEBUG entry is filled in by the
2871 dynamic linker and used by the debugger. */
2872 if (! info->shared)
2874 if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
2875 return false;
2878 if (plt)
2880 if (! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
2881 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
2882 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
2883 || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
2884 return false;
2887 if (relocs)
2889 if (! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
2890 || ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
2891 || ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
2892 sizeof (Elf32_External_Rel)))
2893 return false;
2896 if (reltext)
2898 if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
2899 return false;
2903 return true;
2906 /* This function is called via elf32_arm_link_hash_traverse if we are
2907 creating a shared object with -Bsymbolic. It discards the space
2908 allocated to copy PC relative relocs against symbols which are
2909 defined in regular objects. We allocated space for them in the
2910 check_relocs routine, but we won't fill them in in the
2911 relocate_section routine. */
2913 static boolean
2914 elf32_arm_discard_copies (h, ignore)
2915 struct elf32_arm_link_hash_entry * h;
2916 PTR ignore ATTRIBUTE_UNUSED;
2918 struct elf32_arm_pcrel_relocs_copied * s;
2920 /* We only discard relocs for symbols defined in a regular object. */
2921 if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2922 return true;
2924 for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
2925 s->section->_raw_size -= s->count * sizeof (Elf32_External_Rel);
2927 return true;
2930 /* Finish up dynamic symbol handling. We set the contents of various
2931 dynamic sections here. */
2933 static boolean
2934 elf32_arm_finish_dynamic_symbol (output_bfd, info, h, sym)
2935 bfd * output_bfd;
2936 struct bfd_link_info * info;
2937 struct elf_link_hash_entry * h;
2938 Elf_Internal_Sym * sym;
2940 bfd * dynobj;
2942 dynobj = elf_hash_table (info)->dynobj;
2944 if (h->plt.offset != (bfd_vma) -1)
2946 asection * splt;
2947 asection * sgot;
2948 asection * srel;
2949 bfd_vma plt_index;
2950 bfd_vma got_offset;
2951 Elf_Internal_Rel rel;
2953 /* This symbol has an entry in the procedure linkage table. Set
2954 it up. */
2956 BFD_ASSERT (h->dynindx != -1);
2958 splt = bfd_get_section_by_name (dynobj, ".plt");
2959 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
2960 srel = bfd_get_section_by_name (dynobj, ".rel.plt");
2961 BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
2963 /* Get the index in the procedure linkage table which
2964 corresponds to this symbol. This is the index of this symbol
2965 in all the symbols for which we are making plt entries. The
2966 first entry in the procedure linkage table is reserved. */
2967 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2969 /* Get the offset into the .got table of the entry that
2970 corresponds to this function. Each .got entry is 4 bytes.
2971 The first three are reserved. */
2972 got_offset = (plt_index + 3) * 4;
2974 /* Fill in the entry in the procedure linkage table. */
2975 memcpy (splt->contents + h->plt.offset,
2976 elf32_arm_plt_entry,
2977 PLT_ENTRY_SIZE);
2978 bfd_put_32 (output_bfd,
2979 (sgot->output_section->vma
2980 + sgot->output_offset
2981 + got_offset
2982 - splt->output_section->vma
2983 - splt->output_offset
2984 - h->plt.offset - 12),
2985 splt->contents + h->plt.offset + 12);
2987 /* Fill in the entry in the global offset table. */
2988 bfd_put_32 (output_bfd,
2989 (splt->output_section->vma
2990 + splt->output_offset),
2991 sgot->contents + got_offset);
2993 /* Fill in the entry in the .rel.plt section. */
2994 rel.r_offset = (sgot->output_section->vma
2995 + sgot->output_offset
2996 + got_offset);
2997 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_JUMP_SLOT);
2998 bfd_elf32_swap_reloc_out (output_bfd, &rel,
2999 ((Elf32_External_Rel *) srel->contents
3000 + plt_index));
3002 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3004 /* Mark the symbol as undefined, rather than as defined in
3005 the .plt section. Leave the value alone. */
3006 sym->st_shndx = SHN_UNDEF;
3010 if (h->got.offset != (bfd_vma) -1)
3012 asection * sgot;
3013 asection * srel;
3014 Elf_Internal_Rel rel;
3016 /* This symbol has an entry in the global offset table. Set it
3017 up. */
3019 sgot = bfd_get_section_by_name (dynobj, ".got");
3020 srel = bfd_get_section_by_name (dynobj, ".rel.got");
3021 BFD_ASSERT (sgot != NULL && srel != NULL);
3023 rel.r_offset = (sgot->output_section->vma
3024 + sgot->output_offset
3025 + (h->got.offset &~ 1));
3027 /* If this is a -Bsymbolic link, and the symbol is defined
3028 locally, we just want to emit a RELATIVE reloc. The entry in
3029 the global offset table will already have been initialized in
3030 the relocate_section function. */
3031 if (info->shared
3032 && (info->symbolic || h->dynindx == -1)
3033 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
3034 rel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
3035 else
3037 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
3038 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_GLOB_DAT);
3041 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3042 ((Elf32_External_Rel *) srel->contents
3043 + srel->reloc_count));
3044 ++srel->reloc_count;
3047 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
3049 asection * s;
3050 Elf_Internal_Rel rel;
3052 /* This symbol needs a copy reloc. Set it up. */
3054 BFD_ASSERT (h->dynindx != -1
3055 && (h->root.type == bfd_link_hash_defined
3056 || h->root.type == bfd_link_hash_defweak));
3058 s = bfd_get_section_by_name (h->root.u.def.section->owner,
3059 ".rel.bss");
3060 BFD_ASSERT (s != NULL);
3062 rel.r_offset = (h->root.u.def.value
3063 + h->root.u.def.section->output_section->vma
3064 + h->root.u.def.section->output_offset);
3065 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_COPY);
3066 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3067 ((Elf32_External_Rel *) s->contents
3068 + s->reloc_count));
3069 ++s->reloc_count;
3072 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3073 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3074 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
3075 sym->st_shndx = SHN_ABS;
3077 return true;
3080 /* Finish up the dynamic sections. */
3082 static boolean
3083 elf32_arm_finish_dynamic_sections (output_bfd, info)
3084 bfd * output_bfd;
3085 struct bfd_link_info * info;
3087 bfd * dynobj;
3088 asection * sgot;
3089 asection * sdyn;
3091 dynobj = elf_hash_table (info)->dynobj;
3093 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
3094 BFD_ASSERT (sgot != NULL);
3095 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3097 if (elf_hash_table (info)->dynamic_sections_created)
3099 asection *splt;
3100 Elf32_External_Dyn *dyncon, *dynconend;
3102 splt = bfd_get_section_by_name (dynobj, ".plt");
3103 BFD_ASSERT (splt != NULL && sdyn != NULL);
3105 dyncon = (Elf32_External_Dyn *) sdyn->contents;
3106 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
3107 for (; dyncon < dynconend; dyncon++)
3109 Elf_Internal_Dyn dyn;
3110 const char * name;
3111 asection * s;
3113 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
3115 switch (dyn.d_tag)
3117 default:
3118 break;
3120 case DT_PLTGOT:
3121 name = ".got";
3122 goto get_vma;
3123 case DT_JMPREL:
3124 name = ".rel.plt";
3125 get_vma:
3126 s = bfd_get_section_by_name (output_bfd, name);
3127 BFD_ASSERT (s != NULL);
3128 dyn.d_un.d_ptr = s->vma;
3129 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3130 break;
3132 case DT_PLTRELSZ:
3133 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3134 BFD_ASSERT (s != NULL);
3135 if (s->_cooked_size != 0)
3136 dyn.d_un.d_val = s->_cooked_size;
3137 else
3138 dyn.d_un.d_val = s->_raw_size;
3139 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3140 break;
3142 case DT_RELSZ:
3143 /* My reading of the SVR4 ABI indicates that the
3144 procedure linkage table relocs (DT_JMPREL) should be
3145 included in the overall relocs (DT_REL). This is
3146 what Solaris does. However, UnixWare can not handle
3147 that case. Therefore, we override the DT_RELSZ entry
3148 here to make it not include the JMPREL relocs. Since
3149 the linker script arranges for .rel.plt to follow all
3150 other relocation sections, we don't have to worry
3151 about changing the DT_REL entry. */
3152 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3153 if (s != NULL)
3155 if (s->_cooked_size != 0)
3156 dyn.d_un.d_val -= s->_cooked_size;
3157 else
3158 dyn.d_un.d_val -= s->_raw_size;
3160 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3161 break;
3165 /* Fill in the first entry in the procedure linkage table. */
3166 if (splt->_raw_size > 0)
3167 memcpy (splt->contents, elf32_arm_plt0_entry, PLT_ENTRY_SIZE);
3169 /* UnixWare sets the entsize of .plt to 4, although that doesn't
3170 really seem like the right value. */
3171 elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
3174 /* Fill in the first three entries in the global offset table. */
3175 if (sgot->_raw_size > 0)
3177 if (sdyn == NULL)
3178 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
3179 else
3180 bfd_put_32 (output_bfd,
3181 sdyn->output_section->vma + sdyn->output_offset,
3182 sgot->contents);
3183 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
3184 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
3187 elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
3189 return true;
3192 static void
3193 elf32_arm_post_process_headers (abfd, link_info)
3194 bfd * abfd;
3195 struct bfd_link_info * link_info ATTRIBUTE_UNUSED;
3197 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
3199 i_ehdrp = elf_elfheader (abfd);
3201 i_ehdrp->e_ident[EI_OSABI] = ARM_ELF_OS_ABI_VERSION;
3202 i_ehdrp->e_ident[EI_ABIVERSION] = ARM_ELF_ABI_VERSION;
3206 #define ELF_ARCH bfd_arch_arm
3207 #define ELF_MACHINE_CODE EM_ARM
3208 #define ELF_MAXPAGESIZE 0x8000
3211 #define bfd_elf32_bfd_copy_private_bfd_data elf32_arm_copy_private_bfd_data
3212 #define bfd_elf32_bfd_merge_private_bfd_data elf32_arm_merge_private_bfd_data
3213 #define bfd_elf32_bfd_set_private_flags elf32_arm_set_private_flags
3214 #define bfd_elf32_bfd_print_private_bfd_data elf32_arm_print_private_bfd_data
3215 #define bfd_elf32_bfd_link_hash_table_create elf32_arm_link_hash_table_create
3216 #define bfd_elf32_bfd_reloc_type_lookup elf32_arm_reloc_type_lookup
3217 #define bfd_elf32_find_nearest_line elf32_arm_find_nearest_line
3219 #define elf_backend_get_symbol_type elf32_arm_get_symbol_type
3220 #define elf_backend_gc_mark_hook elf32_arm_gc_mark_hook
3221 #define elf_backend_gc_sweep_hook elf32_arm_gc_sweep_hook
3222 #define elf_backend_check_relocs elf32_arm_check_relocs
3223 #define elf_backend_relocate_section elf32_arm_relocate_section
3224 #define elf_backend_adjust_dynamic_symbol elf32_arm_adjust_dynamic_symbol
3225 #define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
3226 #define elf_backend_finish_dynamic_symbol elf32_arm_finish_dynamic_symbol
3227 #define elf_backend_finish_dynamic_sections elf32_arm_finish_dynamic_sections
3228 #define elf_backend_size_dynamic_sections elf32_arm_size_dynamic_sections
3229 #define elf_backend_post_process_headers elf32_arm_post_process_headers
3231 #define elf_backend_can_gc_sections 1
3232 #define elf_backend_plt_readonly 1
3233 #define elf_backend_want_got_plt 1
3234 #define elf_backend_want_plt_sym 0
3236 #define elf_backend_got_header_size 12
3237 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
3239 #include "elf32-target.h"