1999-09-12 Donn Terry <donn@interix.com>
[binutils.git] / bfd / elf32-arm.h
blobfe7fa82cb88bd755d293557ac95cf8d4b63c4b6c
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 calles 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, #-4] */
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 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
550 sec = bfd_make_section (abfd, ARM2THUMB_GLUE_SECTION_NAME);
552 if (sec == NULL
553 || !bfd_set_section_flags (abfd, sec, flags)
554 || !bfd_set_section_alignment (abfd, sec, 2))
555 return false;
558 sec = bfd_get_section_by_name (abfd, THUMB2ARM_GLUE_SECTION_NAME);
560 if (sec == NULL)
562 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
564 sec = bfd_make_section (abfd, THUMB2ARM_GLUE_SECTION_NAME);
566 if (sec == NULL
567 || !bfd_set_section_flags (abfd, sec, flags)
568 || !bfd_set_section_alignment (abfd, sec, 2))
569 return false;
572 /* Save the bfd for later use. */
573 globals->bfd_of_glue_owner = abfd;
575 return true;
578 boolean
579 bfd_elf32_arm_process_before_allocation (abfd, link_info, no_pipeline_knowledge)
580 bfd *abfd;
581 struct bfd_link_info *link_info;
582 int no_pipeline_knowledge;
584 Elf_Internal_Shdr *symtab_hdr;
585 Elf_Internal_Rela *free_relocs = NULL;
586 Elf_Internal_Rela *irel, *irelend;
587 bfd_byte *contents = NULL;
588 bfd_byte *free_contents = NULL;
589 Elf32_External_Sym *extsyms = NULL;
590 Elf32_External_Sym *free_extsyms = NULL;
592 asection *sec;
593 struct elf32_arm_link_hash_table *globals;
595 /* If we are only performing a partial link do not bother
596 to construct any glue. */
597 if (link_info->relocateable)
598 return true;
600 /* Here we have a bfd that is to be included on the link. We have a hook
601 to do reloc rummaging, before section sizes are nailed down. */
603 globals = elf32_arm_hash_table (link_info);
605 BFD_ASSERT (globals != NULL);
606 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
608 globals->no_pipeline_knowledge = no_pipeline_knowledge;
610 /* Rummage around all the relocs and map the glue vectors. */
611 sec = abfd->sections;
613 if (sec == NULL)
614 return true;
616 for (; sec != NULL; sec = sec->next)
618 if (sec->reloc_count == 0)
619 continue;
621 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
622 /* Load the relocs. */
624 irel = (_bfd_elf32_link_read_relocs (abfd, sec, (PTR) NULL,
625 (Elf_Internal_Rela *) NULL, false));
627 BFD_ASSERT (irel != 0);
629 irelend = irel + sec->reloc_count;
630 for (; irel < irelend; irel++)
632 long r_type;
633 unsigned long r_index;
635 struct elf_link_hash_entry *h;
637 r_type = ELF32_R_TYPE (irel->r_info);
638 r_index = ELF32_R_SYM (irel->r_info);
640 /* These are the only relocation types we care about */
641 if ( r_type != R_ARM_PC24
642 && r_type != R_ARM_THM_PC22)
643 continue;
645 /* Get the section contents if we haven't done so already. */
646 if (contents == NULL)
648 /* Get cached copy if it exists. */
649 if (elf_section_data (sec)->this_hdr.contents != NULL)
650 contents = elf_section_data (sec)->this_hdr.contents;
651 else
653 /* Go get them off disk. */
654 contents = (bfd_byte *) bfd_malloc (sec->_raw_size);
655 if (contents == NULL)
656 goto error_return;
657 free_contents = contents;
659 if (!bfd_get_section_contents (abfd, sec, contents,
660 (file_ptr) 0, sec->_raw_size))
661 goto error_return;
665 /* Read this BFD's symbols if we haven't done so already. */
666 if (extsyms == NULL)
668 /* Get cached copy if it exists. */
669 if (symtab_hdr->contents != NULL)
670 extsyms = (Elf32_External_Sym *) symtab_hdr->contents;
671 else
673 /* Go get them off disk. */
674 extsyms = ((Elf32_External_Sym *)
675 bfd_malloc (symtab_hdr->sh_size));
676 if (extsyms == NULL)
677 goto error_return;
678 free_extsyms = extsyms;
679 if (bfd_seek (abfd, symtab_hdr->sh_offset, SEEK_SET) != 0
680 || (bfd_read (extsyms, 1, symtab_hdr->sh_size, abfd)
681 != symtab_hdr->sh_size))
682 goto error_return;
686 /* If the relocation is not against a symbol it cannot concern us. */
688 h = NULL;
690 /* We don't care about local symbols */
691 if (r_index < symtab_hdr->sh_info)
692 continue;
694 /* This is an external symbol */
695 r_index -= symtab_hdr->sh_info;
696 h = (struct elf_link_hash_entry *)
697 elf_sym_hashes (abfd)[r_index];
699 /* If the relocation is against a static symbol it must be within
700 the current section and so cannot be a cross ARM/Thumb relocation. */
701 if (h == NULL)
702 continue;
704 switch (r_type)
706 case R_ARM_PC24:
707 /* This one is a call from arm code. We need to look up
708 the target of the call. If it is a thumb target, we
709 insert glue. */
711 if (ELF_ST_TYPE(h->type) == STT_ARM_TFUNC)
712 record_arm_to_thumb_glue (link_info, h);
713 break;
715 case R_ARM_THM_PC22:
716 /* This one is a call from thumb code. We look
717 up the target of the call. If it is not a thumb
718 target, we insert glue. */
720 if (ELF_ST_TYPE (h->type) != STT_ARM_TFUNC)
721 record_thumb_to_arm_glue (link_info, h);
722 break;
724 default:
725 break;
730 return true;
731 error_return:
732 if (free_relocs != NULL)
733 free (free_relocs);
734 if (free_contents != NULL)
735 free (free_contents);
736 if (free_extsyms != NULL)
737 free (free_extsyms);
738 return false;
742 /* The thumb form of a long branch is a bit finicky, because the offset
743 encoding is split over two fields, each in it's own instruction. They
744 can occur in any order. So given a thumb form of long branch, and an
745 offset, insert the offset into the thumb branch and return finished
746 instruction.
748 It takes two thumb instructions to encode the target address. Each has
749 11 bits to invest. The upper 11 bits are stored in one (identifed by
750 H-0.. see below), the lower 11 bits are stored in the other (identified
751 by H-1).
753 Combine together and shifted left by 1 (it's a half word address) and
754 there you have it.
756 Op: 1111 = F,
757 H-0, upper address-0 = 000
758 Op: 1111 = F,
759 H-1, lower address-0 = 800
761 They can be ordered either way, but the arm tools I've seen always put
762 the lower one first. It probably doesn't matter. krk@cygnus.com
764 XXX: Actually the order does matter. The second instruction (H-1)
765 moves the computed address into the PC, so it must be the second one
766 in the sequence. The problem, however is that whilst little endian code
767 stores the instructions in HI then LOW order, big endian code does the
768 reverse. nickc@cygnus.com */
770 #define LOW_HI_ORDER 0xF800F000
771 #define HI_LOW_ORDER 0xF000F800
773 static insn32
774 insert_thumb_branch (br_insn, rel_off)
775 insn32 br_insn;
776 int rel_off;
778 unsigned int low_bits;
779 unsigned int high_bits;
782 BFD_ASSERT ((rel_off & 1) != 1);
784 rel_off >>= 1; /* half word aligned address */
785 low_bits = rel_off & 0x000007FF; /* the bottom 11 bits */
786 high_bits = (rel_off >> 11) & 0x000007FF; /* the top 11 bits */
788 if ((br_insn & LOW_HI_ORDER) == LOW_HI_ORDER)
789 br_insn = LOW_HI_ORDER | (low_bits << 16) | high_bits;
790 else if ((br_insn & HI_LOW_ORDER) == HI_LOW_ORDER)
791 br_insn = HI_LOW_ORDER | (high_bits << 16) | low_bits;
792 else
793 abort (); /* error - not a valid branch instruction form */
795 /* FIXME: abort is probably not the right call. krk@cygnus.com */
797 return br_insn;
800 /* Thumb code calling an ARM function */
801 static int
802 elf32_thumb_to_arm_stub (info, name, input_bfd, output_bfd, input_section,
803 hit_data, sym_sec, offset, addend, val)
804 struct bfd_link_info * info;
805 const char * name;
806 bfd * input_bfd;
807 bfd * output_bfd;
808 asection * input_section;
809 bfd_byte * hit_data;
810 asection * sym_sec;
811 bfd_vma offset;
812 bfd_signed_vma addend;
813 bfd_vma val;
815 asection * s = 0;
816 long int my_offset;
817 unsigned long int tmp;
818 long int ret_offset;
819 struct elf_link_hash_entry * myh;
820 struct elf32_arm_link_hash_table * globals;
822 myh = find_thumb_glue (info, name, input_bfd);
823 if (myh == NULL)
824 return false;
826 globals = elf32_arm_hash_table (info);
828 BFD_ASSERT (globals != NULL);
829 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
831 my_offset = myh->root.u.def.value;
833 s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
834 THUMB2ARM_GLUE_SECTION_NAME);
836 BFD_ASSERT (s != NULL);
837 BFD_ASSERT (s->contents != NULL);
838 BFD_ASSERT (s->output_section != NULL);
840 if ((my_offset & 0x01) == 0x01)
842 if (sym_sec != NULL
843 && sym_sec->owner != NULL
844 && !INTERWORK_FLAG (sym_sec->owner))
846 _bfd_error_handler
847 (_ ("%s(%s): warning: interworking not enabled."),
848 bfd_get_filename (sym_sec->owner), name);
849 _bfd_error_handler
850 (_ (" first occurrence: %s: thumb call to arm"),
851 bfd_get_filename (input_bfd));
853 return false;
856 --my_offset;
857 myh->root.u.def.value = my_offset;
859 bfd_put_16 (output_bfd, t2a1_bx_pc_insn,
860 s->contents + my_offset);
862 bfd_put_16 (output_bfd, t2a2_noop_insn,
863 s->contents + my_offset + 2);
865 ret_offset =
866 ((bfd_signed_vma) val) /* Address of destination of the stub */
867 - ((bfd_signed_vma)
868 (s->output_offset /* Offset from the start of the current section to the start of the stubs. */
869 + my_offset /* Offset of the start of this stub from the start of the stubs. */
870 + s->output_section->vma) /* Address of the start of the current section. */
871 + 4 /* The branch instruction is 4 bytes into the stub. */
872 + 8); /* ARM branches work from the pc of the instruction + 8. */
874 bfd_put_32 (output_bfd,
875 t2a3_b_insn | ((ret_offset >> 2) & 0x00FFFFFF),
876 s->contents + my_offset + 4);
879 BFD_ASSERT (my_offset <= globals->thumb_glue_size);
881 /* Now go back and fix up the original BL insn to point
882 to here. */
883 ret_offset =
884 s->output_offset
885 + my_offset
886 - (input_section->output_offset
887 + offset + addend)
888 - 4;
890 tmp = bfd_get_32 (input_bfd, hit_data
891 - input_section->vma);
893 bfd_put_32 (output_bfd,
894 insert_thumb_branch (tmp, ret_offset),
895 hit_data - input_section->vma);
897 return true;
900 /* Arm code calling a Thumb function */
901 static int
902 elf32_arm_to_thumb_stub (info, name, input_bfd, output_bfd, input_section,
903 hit_data, sym_sec, offset, addend, val)
904 struct bfd_link_info * info;
905 const char * name;
906 bfd * input_bfd;
907 bfd * output_bfd;
908 asection * input_section;
909 bfd_byte * hit_data;
910 asection * sym_sec;
911 bfd_vma offset;
912 bfd_signed_vma addend;
913 bfd_vma val;
915 unsigned long int tmp;
916 long int my_offset;
917 asection * s;
918 long int ret_offset;
919 struct elf_link_hash_entry * myh;
920 struct elf32_arm_link_hash_table * globals;
922 myh = find_arm_glue (info, name, input_bfd);
923 if (myh == NULL)
924 return false;
926 globals = elf32_arm_hash_table (info);
928 BFD_ASSERT (globals != NULL);
929 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
931 my_offset = myh->root.u.def.value;
932 s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
933 ARM2THUMB_GLUE_SECTION_NAME);
934 BFD_ASSERT (s != NULL);
935 BFD_ASSERT (s->contents != NULL);
936 BFD_ASSERT (s->output_section != NULL);
938 if ((my_offset & 0x01) == 0x01)
940 if (sym_sec != NULL
941 && sym_sec->owner != NULL
942 && !INTERWORK_FLAG (sym_sec->owner))
944 _bfd_error_handler
945 (_ ("%s(%s): warning: interworking not enabled."),
946 bfd_get_filename (sym_sec->owner), name);
947 _bfd_error_handler
948 (_ (" first occurrence: %s: arm call to thumb"),
949 bfd_get_filename (input_bfd));
951 --my_offset;
952 myh->root.u.def.value = my_offset;
954 bfd_put_32 (output_bfd, a2t1_ldr_insn,
955 s->contents + my_offset);
957 bfd_put_32 (output_bfd, a2t2_bx_r12_insn,
958 s->contents + my_offset + 4);
960 /* It's a thumb address. Add the low order bit. */
961 bfd_put_32 (output_bfd, val | a2t3_func_addr_insn,
962 s->contents + my_offset + 8);
965 BFD_ASSERT (my_offset <= globals->arm_glue_size);
967 tmp = bfd_get_32 (input_bfd, hit_data);
968 tmp = tmp & 0xFF000000;
970 /* Somehow these are both 4 too far, so subtract 8. */
971 ret_offset = s->output_offset
972 + my_offset
973 + s->output_section->vma
974 - (input_section->output_offset
975 + input_section->output_section->vma
976 + offset + addend)
977 - 8;
979 tmp = tmp | ((ret_offset >> 2) & 0x00FFFFFF);
981 bfd_put_32 (output_bfd, tmp, hit_data
982 - input_section->vma);
984 return true;
987 /* Perform a relocation as part of a final link. */
988 static bfd_reloc_status_type
989 elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
990 input_section, contents, rel, value,
991 info, sym_sec, sym_name, sym_flags, h)
992 reloc_howto_type * howto;
993 bfd * input_bfd;
994 bfd * output_bfd;
995 asection * input_section;
996 bfd_byte * contents;
997 Elf_Internal_Rela * rel;
998 bfd_vma value;
999 struct bfd_link_info * info;
1000 asection * sym_sec;
1001 const char * sym_name;
1002 unsigned char sym_flags;
1003 struct elf_link_hash_entry * h;
1005 unsigned long r_type = howto->type;
1006 unsigned long r_symndx;
1007 bfd_byte * hit_data = contents + rel->r_offset;
1008 bfd * dynobj = NULL;
1009 Elf_Internal_Shdr * symtab_hdr;
1010 struct elf_link_hash_entry ** sym_hashes;
1011 bfd_vma * local_got_offsets;
1012 asection * sgot = NULL;
1013 asection * splt = NULL;
1014 asection * sreloc = NULL;
1015 bfd_vma addend;
1016 bfd_signed_vma signed_addend;
1017 struct elf32_arm_link_hash_table * globals;
1019 globals = elf32_arm_hash_table (info);
1021 dynobj = elf_hash_table (info)->dynobj;
1022 if (dynobj)
1024 sgot = bfd_get_section_by_name (dynobj, ".got");
1025 splt = bfd_get_section_by_name (dynobj, ".plt");
1027 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1028 sym_hashes = elf_sym_hashes (input_bfd);
1029 local_got_offsets = elf_local_got_offsets (input_bfd);
1030 r_symndx = ELF32_R_SYM (rel->r_info);
1032 #ifdef USE_REL
1033 addend = bfd_get_32 (input_bfd, hit_data) & howto->src_mask;
1035 if (addend & ((howto->src_mask + 1) >> 1))
1037 signed_addend = -1;
1038 signed_addend &= ~ howto->src_mask;
1039 signed_addend |= addend;
1041 else
1042 signed_addend = addend;
1043 #else
1044 addend = signed_addend = rel->r_addend;
1045 #endif
1047 switch (r_type)
1049 case R_ARM_NONE:
1050 return bfd_reloc_ok;
1052 case R_ARM_PC24:
1053 case R_ARM_ABS32:
1054 case R_ARM_REL32:
1055 /* When generating a shared object, these relocations are copied
1056 into the output file to be resolved at run time. */
1058 if (info->shared
1059 && (r_type != R_ARM_PC24
1060 || (h != NULL
1061 && h->dynindx != -1
1062 && (! info->symbolic
1063 || (h->elf_link_hash_flags
1064 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1066 Elf_Internal_Rel outrel;
1067 boolean skip, relocate;
1069 if (sreloc == NULL)
1071 const char * name;
1073 name = (bfd_elf_string_from_elf_section
1074 (input_bfd,
1075 elf_elfheader (input_bfd)->e_shstrndx,
1076 elf_section_data (input_section)->rel_hdr.sh_name));
1077 if (name == NULL)
1078 return bfd_reloc_notsupported;
1080 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
1081 && strcmp (bfd_get_section_name (input_bfd,
1082 input_section),
1083 name + 4) == 0);
1085 sreloc = bfd_get_section_by_name (dynobj, name);
1086 BFD_ASSERT (sreloc != NULL);
1089 skip = false;
1091 if (elf_section_data (input_section)->stab_info == NULL)
1092 outrel.r_offset = rel->r_offset;
1093 else
1095 bfd_vma off;
1097 off = (_bfd_stab_section_offset
1098 (output_bfd, &elf_hash_table (info)->stab_info,
1099 input_section,
1100 & elf_section_data (input_section)->stab_info,
1101 rel->r_offset));
1102 if (off == (bfd_vma) -1)
1103 skip = true;
1104 outrel.r_offset = off;
1107 outrel.r_offset += (input_section->output_section->vma
1108 + input_section->output_offset);
1110 if (skip)
1112 memset (&outrel, 0, sizeof outrel);
1113 relocate = false;
1115 else if (r_type == R_ARM_PC24)
1117 BFD_ASSERT (h != NULL && h->dynindx != -1);
1118 if ((input_section->flags & SEC_ALLOC) != 0)
1119 relocate = false;
1120 else
1121 relocate = true;
1122 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_PC24);
1124 else
1126 if (h == NULL
1127 || ((info->symbolic || h->dynindx == -1)
1128 && (h->elf_link_hash_flags
1129 & ELF_LINK_HASH_DEF_REGULAR) != 0))
1131 relocate = true;
1132 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1134 else
1136 BFD_ASSERT (h->dynindx != -1);
1137 if ((input_section->flags & SEC_ALLOC) != 0)
1138 relocate = false;
1139 else
1140 relocate = true;
1141 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_ABS32);
1145 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1146 (((Elf32_External_Rel *)
1147 sreloc->contents)
1148 + sreloc->reloc_count));
1149 ++sreloc->reloc_count;
1151 /* If this reloc is against an external symbol, we do not want to
1152 fiddle with the addend. Otherwise, we need to include the symbol
1153 value so that it becomes an addend for the dynamic reloc. */
1154 if (! relocate)
1155 return bfd_reloc_ok;
1158 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1159 contents, rel->r_offset, value,
1160 (bfd_vma) 0);
1162 else switch (r_type)
1164 case R_ARM_PC24:
1165 /* Arm B/BL instruction */
1167 /* Check for arm calling thumb function. */
1168 if (sym_flags == STT_ARM_TFUNC)
1170 elf32_arm_to_thumb_stub (info, sym_name, input_bfd, output_bfd,
1171 input_section, hit_data, sym_sec, rel->r_offset,
1172 signed_addend, value);
1173 return bfd_reloc_ok;
1176 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1177 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0)
1179 /* The old way of doing things. Trearing the addend as a
1180 byte sized field and adding in the pipeline offset. */
1182 value -= (input_section->output_section->vma
1183 + input_section->output_offset);
1184 value -= rel->r_offset;
1185 value += addend;
1187 if (! globals->no_pipeline_knowledge)
1188 value -= 8;
1190 else
1192 /* The ARM ELF ABI says that this reloc is computed as: S - P + A
1193 where:
1194 S is the address of the symbol in the relocation.
1195 P is address of the instruction being relocated.
1196 A is the addend (extracted from the instruction) in bytes.
1198 S is held in 'value'.
1199 P is the base address of the section containing the instruction
1200 plus the offset of the reloc into that section, ie:
1201 (input_section->output_section->vma +
1202 input_section->output_offset +
1203 rel->r_offset).
1204 A is the addend, converted into bytes, ie:
1205 (signed_addend * 4)
1207 Note: None of these operations have knowledge of the pipeline
1208 size of the processor, thus it is up to the assembler to encode
1209 this information into the addend. */
1211 value -= (input_section->output_section->vma
1212 + input_section->output_offset);
1213 value -= rel->r_offset;
1214 value += (signed_addend << howto->size);
1216 /* Previous versions of this code also used to add in the pipeline
1217 offset here. This is wrong because the linker is not supposed
1218 to know about such things, and one day it might change. In order
1219 to support old binaries that need the old behaviour however, so
1220 we attempt to detect which ABI was used to create the reloc. */
1221 if (! globals->no_pipeline_knowledge)
1223 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
1225 i_ehdrp = elf_elfheader (input_bfd);
1227 if (i_ehdrp->e_ident[EI_OSABI] == 0)
1228 value -= 8;
1232 /* Perform a signed range check. */
1233 signed_addend = value;
1234 signed_addend >>= howto->rightshift;
1235 if (signed_addend > ((bfd_signed_vma)(howto->dst_mask >> 1))
1236 || signed_addend < - ((bfd_signed_vma) ((howto->dst_mask + 1) >> 1)))
1237 return bfd_reloc_overflow;
1239 value = (signed_addend & howto->dst_mask)
1240 | (bfd_get_32 (input_bfd, hit_data) & (~ howto->dst_mask));
1241 break;
1243 case R_ARM_ABS32:
1244 value += addend;
1245 if (sym_flags == STT_ARM_TFUNC)
1246 value |= 1;
1247 break;
1249 case R_ARM_REL32:
1250 value -= (input_section->output_section->vma
1251 + input_section->output_offset);
1252 value += addend;
1253 break;
1256 bfd_put_32 (input_bfd, value, hit_data);
1257 return bfd_reloc_ok;
1259 case R_ARM_ABS8:
1260 value += addend;
1261 if ((long) value > 0x7f || (long) value < -0x80)
1262 return bfd_reloc_overflow;
1264 bfd_put_8 (input_bfd, value, hit_data);
1265 return bfd_reloc_ok;
1267 case R_ARM_ABS16:
1268 value += addend;
1270 if ((long) value > 0x7fff || (long) value < -0x8000)
1271 return bfd_reloc_overflow;
1273 bfd_put_16 (input_bfd, value, hit_data);
1274 return bfd_reloc_ok;
1276 case R_ARM_ABS12:
1277 /* Support ldr and str instruction for the arm */
1278 /* Also thumb b (unconditional branch). ??? Really? */
1279 value += addend;
1281 if ((long) value > 0x7ff || (long) value < -0x800)
1282 return bfd_reloc_overflow;
1284 value |= (bfd_get_32 (input_bfd, hit_data) & 0xfffff000);
1285 bfd_put_32 (input_bfd, value, hit_data);
1286 return bfd_reloc_ok;
1288 case R_ARM_THM_ABS5:
1289 /* Support ldr and str instructions for the thumb. */
1290 #ifdef USE_REL
1291 /* Need to refetch addend. */
1292 addend = bfd_get_16 (input_bfd, hit_data) & howto->src_mask;
1293 /* ??? Need to determine shift amount from operand size. */
1294 addend >>= howto->rightshift;
1295 #endif
1296 value += addend;
1298 /* ??? Isn't value unsigned? */
1299 if ((long) value > 0x1f || (long) value < -0x10)
1300 return bfd_reloc_overflow;
1302 /* ??? Value needs to be properly shifted into place first. */
1303 value |= bfd_get_16 (input_bfd, hit_data) & 0xf83f;
1304 bfd_put_16 (input_bfd, value, hit_data);
1305 return bfd_reloc_ok;
1307 case R_ARM_THM_PC22:
1308 /* Thumb BL (branch long instruction). */
1310 bfd_vma relocation;
1311 boolean overflow = false;
1312 bfd_vma upper_insn = bfd_get_16 (input_bfd, hit_data);
1313 bfd_vma lower_insn = bfd_get_16 (input_bfd, hit_data + 2);
1314 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
1315 bfd_signed_vma reloc_signed_min = ~ reloc_signed_max;
1316 bfd_vma check;
1317 bfd_signed_vma signed_check;
1319 #ifdef USE_REL
1320 /* Need to refetch the addend and squish the two 11 bit pieces
1321 together. */
1323 bfd_vma upper = upper_insn & 0x7ff;
1324 bfd_vma lower = lower_insn & 0x7ff;
1325 upper = (upper ^ 0x400) - 0x400; /* sign extend */
1326 addend = (upper << 12) | (lower << 1);
1327 signed_addend = addend;
1329 #endif
1331 /* If it is not a call to thumb, assume call to arm.
1332 If it is a call relative to a section name, then it is not a
1333 function call at all, but rather a long jump. */
1334 if (sym_flags != STT_ARM_TFUNC && sym_flags != STT_SECTION)
1336 if (elf32_thumb_to_arm_stub
1337 (info, sym_name, input_bfd, output_bfd, input_section,
1338 hit_data, sym_sec, rel->r_offset, signed_addend, value))
1339 return bfd_reloc_ok;
1340 else
1341 return bfd_reloc_dangerous;
1344 relocation = value + signed_addend;
1346 relocation -= (input_section->output_section->vma
1347 + input_section->output_offset
1348 + rel->r_offset);
1350 if (! globals->no_pipeline_knowledge)
1352 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
1354 i_ehdrp = elf_elfheader (input_bfd);
1356 /* Previous versions of this code also used to add in the pipline
1357 offset here. This is wrong because the linker is not supposed
1358 to know about such things, and one day it might change. In order
1359 to support old binaries that need the old behaviour however, so
1360 we attempt to detect which ABI was used to create the reloc. */
1361 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1362 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0
1363 || i_ehdrp->e_ident[EI_OSABI] == 0)
1364 relocation += 4;
1367 check = relocation >> howto->rightshift;
1369 /* If this is a signed value, the rightshift just dropped
1370 leading 1 bits (assuming twos complement). */
1371 if ((bfd_signed_vma) relocation >= 0)
1372 signed_check = check;
1373 else
1374 signed_check = check | ~((bfd_vma) -1 >> howto->rightshift);
1376 /* Assumes two's complement. */
1377 if (signed_check > reloc_signed_max || signed_check < reloc_signed_min)
1378 overflow = true;
1380 /* Put RELOCATION back into the insn. */
1381 upper_insn = (upper_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 12) & 0x7ff);
1382 lower_insn = (lower_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 1) & 0x7ff);
1384 /* Put the relocated value back in the object file: */
1385 bfd_put_16 (input_bfd, upper_insn, hit_data);
1386 bfd_put_16 (input_bfd, lower_insn, hit_data + 2);
1388 return (overflow ? bfd_reloc_overflow : bfd_reloc_ok);
1390 break;
1392 case R_ARM_GNU_VTINHERIT:
1393 case R_ARM_GNU_VTENTRY:
1394 return bfd_reloc_ok;
1396 case R_ARM_COPY:
1397 return bfd_reloc_notsupported;
1399 case R_ARM_GLOB_DAT:
1400 return bfd_reloc_notsupported;
1402 case R_ARM_JUMP_SLOT:
1403 return bfd_reloc_notsupported;
1405 case R_ARM_RELATIVE:
1406 return bfd_reloc_notsupported;
1408 case R_ARM_GOTOFF:
1409 /* Relocation is relative to the start of the
1410 global offset table. */
1412 BFD_ASSERT (sgot != NULL);
1413 if (sgot == NULL)
1414 return bfd_reloc_notsupported;
1416 /* Note that sgot->output_offset is not involved in this
1417 calculation. We always want the start of .got. If we
1418 define _GLOBAL_OFFSET_TABLE in a different way, as is
1419 permitted by the ABI, we might have to change this
1420 calculation. */
1422 value -= sgot->output_section->vma;
1423 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1424 contents, rel->r_offset, value,
1425 (bfd_vma) 0);
1427 case R_ARM_GOTPC:
1428 /* Use global offset table as symbol value. */
1430 BFD_ASSERT (sgot != NULL);
1432 if (sgot == NULL)
1433 return bfd_reloc_notsupported;
1435 value = sgot->output_section->vma;
1436 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1437 contents, rel->r_offset, value,
1438 (bfd_vma) 0);
1440 case R_ARM_GOT32:
1441 /* Relocation is to the entry for this symbol in the
1442 global offset table. */
1443 if (sgot == NULL)
1444 return bfd_reloc_notsupported;
1446 if (h != NULL)
1448 bfd_vma off;
1450 off = h->got.offset;
1451 BFD_ASSERT (off != (bfd_vma) -1);
1453 if (!elf_hash_table (info)->dynamic_sections_created ||
1454 (info->shared && (info->symbolic || h->dynindx == -1)
1455 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1457 /* This is actually a static link, or it is a -Bsymbolic link
1458 and the symbol is defined locally. We must initialize this
1459 entry in the global offset table. Since the offset must
1460 always be a multiple of 4, we use the least significant bit
1461 to record whether we have initialized it already.
1463 When doing a dynamic link, we create a .rel.got relocation
1464 entry to initialize the value. This is done in the
1465 finish_dynamic_symbol routine. */
1467 if ((off & 1) != 0)
1468 off &= ~1;
1469 else
1471 bfd_put_32 (output_bfd, value, sgot->contents + off);
1472 h->got.offset |= 1;
1476 value = sgot->output_offset + off;
1478 else
1480 bfd_vma off;
1482 BFD_ASSERT (local_got_offsets != NULL &&
1483 local_got_offsets[r_symndx] != (bfd_vma) -1);
1485 off = local_got_offsets[r_symndx];
1487 /* The offset must always be a multiple of 4. We use the
1488 least significant bit to record whether we have already
1489 generated the necessary reloc. */
1490 if ((off & 1) != 0)
1491 off &= ~1;
1492 else
1494 bfd_put_32 (output_bfd, value, sgot->contents + off);
1496 if (info->shared)
1498 asection * srelgot;
1499 Elf_Internal_Rel outrel;
1501 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
1502 BFD_ASSERT (srelgot != NULL);
1504 outrel.r_offset = (sgot->output_section->vma
1505 + sgot->output_offset
1506 + off);
1507 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1508 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1509 (((Elf32_External_Rel *)
1510 srelgot->contents)
1511 + srelgot->reloc_count));
1512 ++srelgot->reloc_count;
1515 local_got_offsets[r_symndx] |= 1;
1518 value = sgot->output_offset + off;
1521 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1522 contents, rel->r_offset, value,
1523 (bfd_vma) 0);
1525 case R_ARM_PLT32:
1526 /* Relocation is to the entry for this symbol in the
1527 procedure linkage table. */
1529 /* Resolve a PLT32 reloc against a local symbol directly,
1530 without using the procedure linkage table. */
1531 if (h == NULL)
1532 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1533 contents, rel->r_offset, value,
1534 (bfd_vma) 0);
1536 if (h->plt.offset == (bfd_vma) -1)
1537 /* We didn't make a PLT entry for this symbol. This
1538 happens when statically linking PIC code, or when
1539 using -Bsymbolic. */
1540 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1541 contents, rel->r_offset, value,
1542 (bfd_vma) 0);
1544 BFD_ASSERT(splt != NULL);
1545 if (splt == NULL)
1546 return bfd_reloc_notsupported;
1548 value = (splt->output_section->vma
1549 + splt->output_offset
1550 + h->plt.offset);
1551 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1552 contents, rel->r_offset, value,
1553 (bfd_vma) 0);
1555 case R_ARM_SBREL32:
1556 return bfd_reloc_notsupported;
1558 case R_ARM_AMP_VCALL9:
1559 return bfd_reloc_notsupported;
1561 case R_ARM_RSBREL32:
1562 return bfd_reloc_notsupported;
1564 case R_ARM_THM_RPC22:
1565 return bfd_reloc_notsupported;
1567 case R_ARM_RREL32:
1568 return bfd_reloc_notsupported;
1570 case R_ARM_RABS32:
1571 return bfd_reloc_notsupported;
1573 case R_ARM_RPC24:
1574 return bfd_reloc_notsupported;
1576 case R_ARM_RBASE:
1577 return bfd_reloc_notsupported;
1579 default:
1580 return bfd_reloc_notsupported;
1584 #ifdef USE_REL
1585 /* Add INCREMENT to the reloc (of type HOWTO) at ADDRESS. */
1586 static void
1587 arm_add_to_rel (abfd, address, howto, increment)
1588 bfd * abfd;
1589 bfd_vma address;
1590 reloc_howto_type * howto;
1591 bfd_signed_vma increment;
1593 bfd_vma contents;
1594 bfd_signed_vma addend;
1596 contents = bfd_get_32 (abfd, address);
1598 /* Get the (signed) value from the instruction. */
1599 addend = contents & howto->src_mask;
1600 if (addend & ((howto->src_mask + 1) >> 1))
1602 bfd_signed_vma mask;
1604 mask = -1;
1605 mask &= ~ howto->src_mask;
1606 addend |= mask;
1609 /* Add in the increment, (which is a byte value). */
1610 switch (howto->type)
1612 case R_ARM_THM_PC22:
1613 default:
1614 addend += increment;
1615 break;
1617 case R_ARM_PC24:
1618 addend <<= howto->size;
1619 addend += increment;
1621 /* Should we check for overflow here ? */
1623 /* Drop any undesired bits. */
1624 addend >>= howto->rightshift;
1625 break;
1628 contents = (contents & ~ howto->dst_mask) | (addend & howto->dst_mask);
1630 bfd_put_32 (abfd, contents, address);
1632 #endif /* USE_REL */
1634 /* Relocate an ARM ELF section. */
1635 static boolean
1636 elf32_arm_relocate_section (output_bfd, info, input_bfd, input_section,
1637 contents, relocs, local_syms, local_sections)
1638 bfd * output_bfd;
1639 struct bfd_link_info * info;
1640 bfd * input_bfd;
1641 asection * input_section;
1642 bfd_byte * contents;
1643 Elf_Internal_Rela * relocs;
1644 Elf_Internal_Sym * local_syms;
1645 asection ** local_sections;
1647 Elf_Internal_Shdr * symtab_hdr;
1648 struct elf_link_hash_entry ** sym_hashes;
1649 Elf_Internal_Rela * rel;
1650 Elf_Internal_Rela * relend;
1651 const char * name;
1653 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1654 sym_hashes = elf_sym_hashes (input_bfd);
1656 rel = relocs;
1657 relend = relocs + input_section->reloc_count;
1658 for (; rel < relend; rel++)
1660 int r_type;
1661 reloc_howto_type * howto;
1662 unsigned long r_symndx;
1663 Elf_Internal_Sym * sym;
1664 asection * sec;
1665 struct elf_link_hash_entry * h;
1666 bfd_vma relocation;
1667 bfd_reloc_status_type r;
1668 arelent bfd_reloc;
1670 r_symndx = ELF32_R_SYM (rel->r_info);
1671 r_type = ELF32_R_TYPE (rel->r_info);
1673 if ( r_type == R_ARM_GNU_VTENTRY
1674 || r_type == R_ARM_GNU_VTINHERIT)
1675 continue;
1677 elf32_arm_info_to_howto (input_bfd, & bfd_reloc, rel);
1678 howto = bfd_reloc.howto;
1680 if (info->relocateable)
1682 /* This is a relocateable link. We don't have to change
1683 anything, unless the reloc is against a section symbol,
1684 in which case we have to adjust according to where the
1685 section symbol winds up in the output section. */
1686 if (r_symndx < symtab_hdr->sh_info)
1688 sym = local_syms + r_symndx;
1689 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1691 sec = local_sections[r_symndx];
1692 #ifdef USE_REL
1693 arm_add_to_rel (input_bfd, contents + rel->r_offset,
1694 howto, sec->output_offset + sym->st_value);
1695 #else
1696 rel->r_addend += (sec->output_offset + sym->st_value)
1697 >> howto->rightshift;
1698 #endif
1702 continue;
1705 /* This is a final link. */
1706 h = NULL;
1707 sym = NULL;
1708 sec = NULL;
1709 if (r_symndx < symtab_hdr->sh_info)
1711 sym = local_syms + r_symndx;
1712 sec = local_sections[r_symndx];
1713 relocation = (sec->output_section->vma
1714 + sec->output_offset
1715 + sym->st_value);
1717 else
1719 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1720 while (h->root.type == bfd_link_hash_indirect
1721 || h->root.type == bfd_link_hash_warning)
1722 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1723 if (h->root.type == bfd_link_hash_defined
1724 || h->root.type == bfd_link_hash_defweak)
1726 int relocation_needed = 1;
1728 sec = h->root.u.def.section;
1730 /* In these cases, we don't need the relocation value.
1731 We check specially because in some obscure cases
1732 sec->output_section will be NULL. */
1733 switch (r_type)
1735 case R_ARM_PC24:
1736 case R_ARM_ABS32:
1737 if (info->shared
1738 && (
1739 (!info->symbolic && h->dynindx != -1)
1740 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1742 && ((input_section->flags & SEC_ALLOC) != 0)
1744 relocation_needed = 0;
1745 break;
1747 case R_ARM_GOTPC:
1748 relocation_needed = 0;
1749 break;
1751 case R_ARM_GOT32:
1752 if (elf_hash_table(info)->dynamic_sections_created
1753 && (!info->shared
1754 || (!info->symbolic && h->dynindx != -1)
1755 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1758 relocation_needed = 0;
1759 break;
1761 case R_ARM_PLT32:
1762 if (h->plt.offset != (bfd_vma)-1)
1763 relocation_needed = 0;
1764 break;
1766 default:
1767 if (sec->output_section == NULL)
1769 (*_bfd_error_handler)
1770 (_("%s: warning: unresolvable relocation against symbol `%s' from %s section"),
1771 bfd_get_filename (input_bfd), h->root.root.string,
1772 bfd_get_section_name (input_bfd, input_section));
1773 relocation_needed = 0;
1777 if (relocation_needed)
1778 relocation = h->root.u.def.value
1779 + sec->output_section->vma
1780 + sec->output_offset;
1781 else
1782 relocation = 0;
1784 else if (h->root.type == bfd_link_hash_undefweak)
1785 relocation = 0;
1786 else if (info->shared && !info->symbolic && !info->no_undefined)
1787 relocation = 0;
1788 else
1790 if (!((*info->callbacks->undefined_symbol)
1791 (info, h->root.root.string, input_bfd,
1792 input_section, rel->r_offset)))
1793 return false;
1794 relocation = 0;
1798 if (h != NULL)
1799 name = h->root.root.string;
1800 else
1802 name = (bfd_elf_string_from_elf_section
1803 (input_bfd, symtab_hdr->sh_link, sym->st_name));
1804 if (name == NULL || *name == '\0')
1805 name = bfd_section_name (input_bfd, sec);
1808 r = elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
1809 input_section, contents, rel,
1810 relocation, info, sec, name,
1811 (h ? ELF_ST_TYPE (h->type) :
1812 ELF_ST_TYPE (sym->st_info)), h);
1814 if (r != bfd_reloc_ok)
1816 const char * msg = (const char *) 0;
1818 switch (r)
1820 case bfd_reloc_overflow:
1821 if (!((*info->callbacks->reloc_overflow)
1822 (info, name, howto->name, (bfd_vma) 0,
1823 input_bfd, input_section, rel->r_offset)))
1824 return false;
1825 break;
1827 case bfd_reloc_undefined:
1828 if (!((*info->callbacks->undefined_symbol)
1829 (info, name, input_bfd, input_section,
1830 rel->r_offset)))
1831 return false;
1832 break;
1834 case bfd_reloc_outofrange:
1835 msg = _ ("internal error: out of range error");
1836 goto common_error;
1838 case bfd_reloc_notsupported:
1839 msg = _ ("internal error: unsupported relocation error");
1840 goto common_error;
1842 case bfd_reloc_dangerous:
1843 msg = _ ("internal error: dangerous error");
1844 goto common_error;
1846 default:
1847 msg = _ ("internal error: unknown error");
1848 /* fall through */
1850 common_error:
1851 if (!((*info->callbacks->warning)
1852 (info, msg, name, input_bfd, input_section,
1853 rel->r_offset)))
1854 return false;
1855 break;
1860 return true;
1863 /* Function to keep ARM specific flags in the ELF header. */
1864 static boolean
1865 elf32_arm_set_private_flags (abfd, flags)
1866 bfd *abfd;
1867 flagword flags;
1869 if (elf_flags_init (abfd)
1870 && elf_elfheader (abfd)->e_flags != flags)
1872 if (flags & EF_INTERWORK)
1873 _bfd_error_handler (_ ("\
1874 Warning: Not setting interwork flag of %s since it has already been specified as non-interworking"),
1875 bfd_get_filename (abfd));
1876 else
1877 _bfd_error_handler (_ ("\
1878 Warning: Clearing the interwork flag of %s due to outside request"),
1879 bfd_get_filename (abfd));
1881 else
1883 elf_elfheader (abfd)->e_flags = flags;
1884 elf_flags_init (abfd) = true;
1887 return true;
1890 /* Copy backend specific data from one object module to another */
1891 static boolean
1892 elf32_arm_copy_private_bfd_data (ibfd, obfd)
1893 bfd *ibfd;
1894 bfd *obfd;
1896 flagword in_flags;
1897 flagword out_flags;
1899 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
1900 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
1901 return true;
1903 in_flags = elf_elfheader (ibfd)->e_flags;
1904 out_flags = elf_elfheader (obfd)->e_flags;
1906 if (elf_flags_init (obfd) && in_flags != out_flags)
1908 /* Cannot mix PIC and non-PIC code. */
1909 if ((in_flags & EF_PIC) != (out_flags & EF_PIC))
1910 return false;
1912 /* Cannot mix APCS26 and APCS32 code. */
1913 if ((in_flags & EF_APCS_26) != (out_flags & EF_APCS_26))
1914 return false;
1916 /* Cannot mix float APCS and non-float APCS code. */
1917 if ((in_flags & EF_APCS_FLOAT) != (out_flags & EF_APCS_FLOAT))
1918 return false;
1920 /* If the src and dest have different interworking flags
1921 then turn off the interworking bit. */
1922 if ((in_flags & EF_INTERWORK) != (out_flags & EF_INTERWORK))
1924 if (out_flags & EF_INTERWORK)
1925 _bfd_error_handler (_ ("\
1926 Warning: Clearing the interwork flag in %s because non-interworking code in %s has been linked with it"),
1927 bfd_get_filename (obfd), bfd_get_filename (ibfd));
1929 in_flags &= ~EF_INTERWORK;
1933 elf_elfheader (obfd)->e_flags = in_flags;
1934 elf_flags_init (obfd) = true;
1936 return true;
1939 /* Merge backend specific data from an object file to the output
1940 object file when linking. */
1941 static boolean
1942 elf32_arm_merge_private_bfd_data (ibfd, obfd)
1943 bfd *ibfd;
1944 bfd *obfd;
1946 flagword out_flags;
1947 flagword in_flags;
1949 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
1950 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
1951 return true;
1953 /* Check if we have the same endianess */
1954 if ( ibfd->xvec->byteorder != obfd->xvec->byteorder
1955 && obfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN
1956 && ibfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
1958 (*_bfd_error_handler)
1959 (_("%s: compiled for a %s endian system and target is %s endian"),
1960 bfd_get_filename (ibfd),
1961 bfd_big_endian (ibfd) ? "big" : "little",
1962 bfd_big_endian (obfd) ? "big" : "little");
1964 bfd_set_error (bfd_error_wrong_format);
1965 return false;
1968 /* The input BFD must have had its flags initialised. */
1969 /* The following seems bogus to me -- The flags are initialized in
1970 the assembler but I don't think an elf_flags_init field is
1971 written into the object */
1972 /* BFD_ASSERT (elf_flags_init (ibfd)); */
1974 in_flags = elf_elfheader (ibfd)->e_flags;
1975 out_flags = elf_elfheader (obfd)->e_flags;
1977 if (!elf_flags_init (obfd))
1979 /* If the input is the default architecture then do not
1980 bother setting the flags for the output architecture,
1981 instead allow future merges to do this. If no future
1982 merges ever set these flags then they will retain their
1983 unitialised values, which surprise surprise, correspond
1984 to the default values. */
1985 if (bfd_get_arch_info (ibfd)->the_default)
1986 return true;
1988 elf_flags_init (obfd) = true;
1989 elf_elfheader (obfd)->e_flags = in_flags;
1991 if (bfd_get_arch (obfd) == bfd_get_arch (ibfd)
1992 && bfd_get_arch_info (obfd)->the_default)
1993 return bfd_set_arch_mach (obfd, bfd_get_arch (ibfd), bfd_get_mach (ibfd));
1995 return true;
1998 /* Check flag compatibility. */
1999 if (in_flags == out_flags)
2000 return true;
2002 /* Complain about various flag mismatches. */
2004 if ((in_flags & EF_APCS_26) != (out_flags & EF_APCS_26))
2005 _bfd_error_handler (_ ("\
2006 Error: %s compiled for APCS-%d, whereas %s is compiled for APCS-%d"),
2007 bfd_get_filename (ibfd),
2008 in_flags & EF_APCS_26 ? 26 : 32,
2009 bfd_get_filename (obfd),
2010 out_flags & EF_APCS_26 ? 26 : 32);
2012 if ((in_flags & EF_APCS_FLOAT) != (out_flags & EF_APCS_FLOAT))
2013 _bfd_error_handler (_ ("\
2014 Error: %s passes floats in %s registers, whereas %s passes them in %s registers"),
2015 bfd_get_filename (ibfd),
2016 in_flags & EF_APCS_FLOAT ? _ ("float") : _ ("integer"),
2017 bfd_get_filename (obfd),
2018 out_flags & EF_APCS_26 ? _ ("float") : _ ("integer"));
2020 if ((in_flags & EF_PIC) != (out_flags & EF_PIC))
2021 _bfd_error_handler (_ ("\
2022 Error: %s is compiled as position %s code, whereas %s is not"),
2023 bfd_get_filename (ibfd),
2024 in_flags & EF_PIC ? _ ("independent") : _ ("dependent"),
2025 bfd_get_filename (obfd));
2027 /* Interworking mismatch is only a warning. */
2028 if ((in_flags & EF_INTERWORK) != (out_flags & EF_INTERWORK))
2030 _bfd_error_handler (_ ("\
2031 Warning: %s %s interworking, whereas %s %s"),
2032 bfd_get_filename (ibfd),
2033 in_flags & EF_INTERWORK ? _ ("supports") : _ ("does not support"),
2034 bfd_get_filename (obfd),
2035 out_flags & EF_INTERWORK ? _ ("does not") : _ ("does"));
2036 return true;
2039 return false;
2042 /* Display the flags field */
2043 static boolean
2044 elf32_arm_print_private_bfd_data (abfd, ptr)
2045 bfd *abfd;
2046 PTR ptr;
2048 FILE *file = (FILE *) ptr;
2050 BFD_ASSERT (abfd != NULL && ptr != NULL);
2052 /* Print normal ELF private data. */
2053 _bfd_elf_print_private_bfd_data (abfd, ptr);
2055 /* Ignore init flag - it may not be set, despite the flags field containing valid data. */
2057 /* xgettext:c-format */
2058 fprintf (file, _ ("private flags = %lx:"), elf_elfheader (abfd)->e_flags);
2060 if (elf_elfheader (abfd)->e_flags & EF_INTERWORK)
2061 fprintf (file, _ (" [interworking enabled]"));
2062 else
2063 fprintf (file, _ (" [interworking not enabled]"));
2065 if (elf_elfheader (abfd)->e_flags & EF_APCS_26)
2066 fprintf (file, _ (" [APCS-26]"));
2067 else
2068 fprintf (file, _ (" [APCS-32]"));
2070 if (elf_elfheader (abfd)->e_flags & EF_APCS_FLOAT)
2071 fprintf (file, _ (" [floats passed in float registers]"));
2072 else
2073 fprintf (file, _ (" [floats passed in integer registers]"));
2075 if (elf_elfheader (abfd)->e_flags & EF_PIC)
2076 fprintf (file, _ (" [position independent]"));
2077 else
2078 fprintf (file, _ (" [absolute position]"));
2080 fputc ('\n', file);
2082 return true;
2085 static int
2086 elf32_arm_get_symbol_type (elf_sym, type)
2087 Elf_Internal_Sym * elf_sym;
2088 int type;
2090 if (ELF_ST_TYPE (elf_sym->st_info) == STT_ARM_TFUNC)
2091 return ELF_ST_TYPE (elf_sym->st_info);
2092 else
2093 return type;
2096 static asection *
2097 elf32_arm_gc_mark_hook (abfd, info, rel, h, sym)
2098 bfd *abfd;
2099 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2100 Elf_Internal_Rela *rel;
2101 struct elf_link_hash_entry *h;
2102 Elf_Internal_Sym *sym;
2104 if (h != NULL)
2106 switch (ELF32_R_TYPE (rel->r_info))
2108 case R_ARM_GNU_VTINHERIT:
2109 case R_ARM_GNU_VTENTRY:
2110 break;
2112 default:
2113 switch (h->root.type)
2115 case bfd_link_hash_defined:
2116 case bfd_link_hash_defweak:
2117 return h->root.u.def.section;
2119 case bfd_link_hash_common:
2120 return h->root.u.c.p->section;
2122 default:
2123 break;
2127 else
2129 if (!(elf_bad_symtab (abfd)
2130 && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
2131 && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
2132 && sym->st_shndx != SHN_COMMON))
2134 return bfd_section_from_elf_index (abfd, sym->st_shndx);
2137 return NULL;
2140 /* Update the got entry reference counts for the section being removed. */
2142 static boolean
2143 elf32_arm_gc_sweep_hook (abfd, info, sec, relocs)
2144 bfd *abfd ATTRIBUTE_UNUSED;
2145 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2146 asection *sec ATTRIBUTE_UNUSED;
2147 const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
2149 /* We don't support garbage collection of GOT and PLT relocs yet. */
2150 return true;
2153 /* Look through the relocs for a section during the first phase. */
2155 static boolean
2156 elf32_arm_check_relocs (abfd, info, sec, relocs)
2157 bfd * abfd;
2158 struct bfd_link_info * info;
2159 asection * sec;
2160 const Elf_Internal_Rela * relocs;
2162 Elf_Internal_Shdr * symtab_hdr;
2163 struct elf_link_hash_entry ** sym_hashes;
2164 struct elf_link_hash_entry ** sym_hashes_end;
2165 const Elf_Internal_Rela * rel;
2166 const Elf_Internal_Rela * rel_end;
2167 bfd * dynobj;
2168 asection * sgot, *srelgot, *sreloc;
2169 bfd_vma * local_got_offsets;
2171 if (info->relocateable)
2172 return true;
2174 sgot = srelgot = sreloc = NULL;
2176 dynobj = elf_hash_table (info)->dynobj;
2177 local_got_offsets = elf_local_got_offsets (abfd);
2179 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2180 sym_hashes = elf_sym_hashes (abfd);
2181 sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof(Elf32_External_Sym);
2182 if (!elf_bad_symtab (abfd))
2183 sym_hashes_end -= symtab_hdr->sh_info;
2185 rel_end = relocs + sec->reloc_count;
2186 for (rel = relocs; rel < rel_end; rel++)
2188 struct elf_link_hash_entry *h;
2189 unsigned long r_symndx;
2191 r_symndx = ELF32_R_SYM (rel->r_info);
2192 if (r_symndx < symtab_hdr->sh_info)
2193 h = NULL;
2194 else
2195 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
2197 /* Some relocs require a global offset table. */
2198 if (dynobj == NULL)
2200 switch (ELF32_R_TYPE (rel->r_info))
2202 case R_ARM_GOT32:
2203 case R_ARM_GOTOFF:
2204 case R_ARM_GOTPC:
2205 elf_hash_table (info)->dynobj = dynobj = abfd;
2206 if (! _bfd_elf_create_got_section (dynobj, info))
2207 return false;
2208 break;
2210 default:
2211 break;
2215 switch (ELF32_R_TYPE (rel->r_info))
2217 case R_ARM_GOT32:
2218 /* This symbol requires a global offset table entry. */
2219 if (sgot == NULL)
2221 sgot = bfd_get_section_by_name (dynobj, ".got");
2222 BFD_ASSERT (sgot != NULL);
2225 /* Get the got relocation section if necessary. */
2226 if (srelgot == NULL
2227 && (h != NULL || info->shared))
2229 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
2231 /* If no got relocation section, make one and initialize. */
2232 if (srelgot == NULL)
2234 srelgot = bfd_make_section (dynobj, ".rel.got");
2235 if (srelgot == NULL
2236 || ! bfd_set_section_flags (dynobj, srelgot,
2237 (SEC_ALLOC
2238 | SEC_LOAD
2239 | SEC_HAS_CONTENTS
2240 | SEC_IN_MEMORY
2241 | SEC_LINKER_CREATED
2242 | SEC_READONLY))
2243 || ! bfd_set_section_alignment (dynobj, srelgot, 2))
2244 return false;
2248 if (h != NULL)
2250 if (h->got.offset != (bfd_vma) -1)
2251 /* We have already allocated space in the .got. */
2252 break;
2254 h->got.offset = sgot->_raw_size;
2256 /* Make sure this symbol is output as a dynamic symbol. */
2257 if (h->dynindx == -1)
2258 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2259 return false;
2261 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2263 else
2265 /* This is a global offset table entry for a local
2266 symbol. */
2267 if (local_got_offsets == NULL)
2269 size_t size;
2270 register unsigned int i;
2272 size = symtab_hdr->sh_info * sizeof (bfd_vma);
2273 local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
2274 if (local_got_offsets == NULL)
2275 return false;
2276 elf_local_got_offsets (abfd) = local_got_offsets;
2277 for (i = 0; i < symtab_hdr->sh_info; i++)
2278 local_got_offsets[i] = (bfd_vma) -1;
2281 if (local_got_offsets[r_symndx] != (bfd_vma) -1)
2282 /* We have already allocated space in the .got. */
2283 break;
2285 local_got_offsets[r_symndx] = sgot->_raw_size;
2287 if (info->shared)
2288 /* If we are generating a shared object, we need to
2289 output a R_ARM_RELATIVE reloc so that the dynamic
2290 linker can adjust this GOT entry. */
2291 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2294 sgot->_raw_size += 4;
2295 break;
2297 case R_ARM_PLT32:
2298 /* This symbol requires a procedure linkage table entry. We
2299 actually build the entry in adjust_dynamic_symbol,
2300 because this might be a case of linking PIC code which is
2301 never referenced by a dynamic object, in which case we
2302 don't need to generate a procedure linkage table entry
2303 after all. */
2305 /* If this is a local symbol, we resolve it directly without
2306 creating a procedure linkage table entry. */
2307 if (h == NULL)
2308 continue;
2310 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
2311 break;
2313 case R_ARM_ABS32:
2314 case R_ARM_REL32:
2315 case R_ARM_PC24:
2316 /* If we are creating a shared library, and this is a reloc
2317 against a global symbol, or a non PC relative reloc
2318 against a local symbol, then we need to copy the reloc
2319 into the shared library. However, if we are linking with
2320 -Bsymbolic, we do not need to copy a reloc against a
2321 global symbol which is defined in an object we are
2322 including in the link (i.e., DEF_REGULAR is set). At
2323 this point we have not seen all the input files, so it is
2324 possible that DEF_REGULAR is not set now but will be set
2325 later (it is never cleared). We account for that
2326 possibility below by storing information in the
2327 pcrel_relocs_copied field of the hash table entry. */
2328 if (info->shared
2329 && (ELF32_R_TYPE (rel->r_info) != R_ARM_PC24
2330 || (h != NULL
2331 && (! info->symbolic
2332 || (h->elf_link_hash_flags
2333 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
2335 /* When creating a shared object, we must copy these
2336 reloc types into the output file. We create a reloc
2337 section in dynobj and make room for this reloc. */
2338 if (sreloc == NULL)
2340 const char * name;
2342 name = (bfd_elf_string_from_elf_section
2343 (abfd,
2344 elf_elfheader (abfd)->e_shstrndx,
2345 elf_section_data (sec)->rel_hdr.sh_name));
2346 if (name == NULL)
2347 return false;
2349 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
2350 && strcmp (bfd_get_section_name (abfd, sec),
2351 name + 4) == 0);
2353 sreloc = bfd_get_section_by_name (dynobj, name);
2354 if (sreloc == NULL)
2356 flagword flags;
2358 sreloc = bfd_make_section (dynobj, name);
2359 flags = (SEC_HAS_CONTENTS | SEC_READONLY
2360 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2361 if ((sec->flags & SEC_ALLOC) != 0)
2362 flags |= SEC_ALLOC | SEC_LOAD;
2363 if (sreloc == NULL
2364 || ! bfd_set_section_flags (dynobj, sreloc, flags)
2365 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
2366 return false;
2370 sreloc->_raw_size += sizeof (Elf32_External_Rel);
2371 /* If we are linking with -Bsymbolic, and this is a
2372 global symbol, we count the number of PC relative
2373 relocations we have entered for this symbol, so that
2374 we can discard them again if the symbol is later
2375 defined by a regular object. Note that this function
2376 is only called if we are using an elf_i386 linker
2377 hash table, which means that h is really a pointer to
2378 an elf_i386_link_hash_entry. */
2379 if (h != NULL && info->symbolic
2380 && ELF32_R_TYPE (rel->r_info) == R_ARM_PC24)
2382 struct elf32_arm_link_hash_entry * eh;
2383 struct elf32_arm_pcrel_relocs_copied * p;
2385 eh = (struct elf32_arm_link_hash_entry *) h;
2387 for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
2388 if (p->section == sreloc)
2389 break;
2391 if (p == NULL)
2393 p = ((struct elf32_arm_pcrel_relocs_copied *)
2394 bfd_alloc (dynobj, sizeof * p));
2396 if (p == NULL)
2397 return false;
2398 p->next = eh->pcrel_relocs_copied;
2399 eh->pcrel_relocs_copied = p;
2400 p->section = sreloc;
2401 p->count = 0;
2404 ++p->count;
2407 break;
2409 /* This relocation describes the C++ object vtable hierarchy.
2410 Reconstruct it for later use during GC. */
2411 case R_ARM_GNU_VTINHERIT:
2412 if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
2413 return false;
2414 break;
2416 /* This relocation describes which C++ vtable entries are actually
2417 used. Record for later use during GC. */
2418 case R_ARM_GNU_VTENTRY:
2419 if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_offset))
2420 return false;
2421 break;
2425 return true;
2429 /* Find the nearest line to a particular section and offset, for error
2430 reporting. This code is a duplicate of the code in elf.c, except
2431 that it also accepts STT_ARM_TFUNC as a symbol that names a function. */
2433 static boolean
2434 elf32_arm_find_nearest_line
2435 (abfd, section, symbols, offset, filename_ptr, functionname_ptr, line_ptr)
2436 bfd * abfd;
2437 asection * section;
2438 asymbol ** symbols;
2439 bfd_vma offset;
2440 CONST char ** filename_ptr;
2441 CONST char ** functionname_ptr;
2442 unsigned int * line_ptr;
2444 boolean found;
2445 const char * filename;
2446 asymbol * func;
2447 bfd_vma low_func;
2448 asymbol ** p;
2450 if (_bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
2451 filename_ptr, functionname_ptr,
2452 line_ptr, 0))
2453 return true;
2455 if (! _bfd_stab_section_find_nearest_line (abfd, symbols, section, offset,
2456 &found, filename_ptr,
2457 functionname_ptr, line_ptr,
2458 &elf_tdata (abfd)->line_info))
2459 return false;
2461 if (found)
2462 return true;
2464 if (symbols == NULL)
2465 return false;
2467 filename = NULL;
2468 func = NULL;
2469 low_func = 0;
2471 for (p = symbols; *p != NULL; p++)
2473 elf_symbol_type *q;
2475 q = (elf_symbol_type *) *p;
2477 if (bfd_get_section (&q->symbol) != section)
2478 continue;
2480 switch (ELF_ST_TYPE (q->internal_elf_sym.st_info))
2482 default:
2483 break;
2484 case STT_FILE:
2485 filename = bfd_asymbol_name (&q->symbol);
2486 break;
2487 case STT_NOTYPE:
2488 case STT_FUNC:
2489 case STT_ARM_TFUNC:
2490 if (q->symbol.section == section
2491 && q->symbol.value >= low_func
2492 && q->symbol.value <= offset)
2494 func = (asymbol *) q;
2495 low_func = q->symbol.value;
2497 break;
2501 if (func == NULL)
2502 return false;
2504 *filename_ptr = filename;
2505 *functionname_ptr = bfd_asymbol_name (func);
2506 *line_ptr = 0;
2508 return true;
2511 /* Adjust a symbol defined by a dynamic object and referenced by a
2512 regular object. The current definition is in some section of the
2513 dynamic object, but we're not including those sections. We have to
2514 change the definition to something the rest of the link can
2515 understand. */
2517 static boolean
2518 elf32_arm_adjust_dynamic_symbol (info, h)
2519 struct bfd_link_info * info;
2520 struct elf_link_hash_entry * h;
2522 bfd * dynobj;
2523 asection * s;
2524 unsigned int power_of_two;
2526 dynobj = elf_hash_table (info)->dynobj;
2528 /* Make sure we know what is going on here. */
2529 BFD_ASSERT (dynobj != NULL
2530 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
2531 || h->weakdef != NULL
2532 || ((h->elf_link_hash_flags
2533 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2534 && (h->elf_link_hash_flags
2535 & ELF_LINK_HASH_REF_REGULAR) != 0
2536 && (h->elf_link_hash_flags
2537 & ELF_LINK_HASH_DEF_REGULAR) == 0)));
2539 /* If this is a function, put it in the procedure linkage table. We
2540 will fill in the contents of the procedure linkage table later,
2541 when we know the address of the .got section. */
2542 if (h->type == STT_FUNC
2543 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
2545 if (! info->shared
2546 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2547 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
2549 /* This case can occur if we saw a PLT32 reloc in an input
2550 file, but the symbol was never referred to by a dynamic
2551 object. In such a case, we don't actually need to build
2552 a procedure linkage table, and we can just do a PC32
2553 reloc instead. */
2554 BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
2555 return true;
2558 /* Make sure this symbol is output as a dynamic symbol. */
2559 if (h->dynindx == -1)
2561 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2562 return false;
2565 s = bfd_get_section_by_name (dynobj, ".plt");
2566 BFD_ASSERT (s != NULL);
2568 /* If this is the first .plt entry, make room for the special
2569 first entry. */
2570 if (s->_raw_size == 0)
2571 s->_raw_size += PLT_ENTRY_SIZE;
2573 /* If this symbol is not defined in a regular file, and we are
2574 not generating a shared library, then set the symbol to this
2575 location in the .plt. This is required to make function
2576 pointers compare as equal between the normal executable and
2577 the shared library. */
2578 if (! info->shared
2579 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2581 h->root.u.def.section = s;
2582 h->root.u.def.value = s->_raw_size;
2585 h->plt.offset = s->_raw_size;
2587 /* Make room for this entry. */
2588 s->_raw_size += PLT_ENTRY_SIZE;
2590 /* We also need to make an entry in the .got.plt section, which
2591 will be placed in the .got section by the linker script. */
2593 s = bfd_get_section_by_name (dynobj, ".got.plt");
2594 BFD_ASSERT (s != NULL);
2595 s->_raw_size += 4;
2597 /* We also need to make an entry in the .rel.plt section. */
2599 s = bfd_get_section_by_name (dynobj, ".rel.plt");
2600 BFD_ASSERT (s != NULL);
2601 s->_raw_size += sizeof (Elf32_External_Rel);
2603 return true;
2606 /* If this is a weak symbol, and there is a real definition, the
2607 processor independent code will have arranged for us to see the
2608 real definition first, and we can just use the same value. */
2609 if (h->weakdef != NULL)
2611 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
2612 || h->weakdef->root.type == bfd_link_hash_defweak);
2613 h->root.u.def.section = h->weakdef->root.u.def.section;
2614 h->root.u.def.value = h->weakdef->root.u.def.value;
2615 return true;
2618 /* This is a reference to a symbol defined by a dynamic object which
2619 is not a function. */
2621 /* If we are creating a shared library, we must presume that the
2622 only references to the symbol are via the global offset table.
2623 For such cases we need not do anything here; the relocations will
2624 be handled correctly by relocate_section. */
2625 if (info->shared)
2626 return true;
2628 /* We must allocate the symbol in our .dynbss section, which will
2629 become part of the .bss section of the executable. There will be
2630 an entry for this symbol in the .dynsym section. The dynamic
2631 object will contain position independent code, so all references
2632 from the dynamic object to this symbol will go through the global
2633 offset table. The dynamic linker will use the .dynsym entry to
2634 determine the address it must put in the global offset table, so
2635 both the dynamic object and the regular object will refer to the
2636 same memory location for the variable. */
2638 s = bfd_get_section_by_name (dynobj, ".dynbss");
2639 BFD_ASSERT (s != NULL);
2641 /* We must generate a R_ARM_COPY reloc to tell the dynamic linker to
2642 copy the initial value out of the dynamic object and into the
2643 runtime process image. We need to remember the offset into the
2644 .rel.bss section we are going to use. */
2645 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
2647 asection *srel;
2649 srel = bfd_get_section_by_name (dynobj, ".rel.bss");
2650 BFD_ASSERT (srel != NULL);
2651 srel->_raw_size += sizeof (Elf32_External_Rel);
2652 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
2655 /* We need to figure out the alignment required for this symbol. I
2656 have no idea how ELF linkers handle this. */
2657 power_of_two = bfd_log2 (h->size);
2658 if (power_of_two > 3)
2659 power_of_two = 3;
2661 /* Apply the required alignment. */
2662 s->_raw_size = BFD_ALIGN (s->_raw_size,
2663 (bfd_size_type) (1 << power_of_two));
2664 if (power_of_two > bfd_get_section_alignment (dynobj, s))
2666 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
2667 return false;
2670 /* Define the symbol as being at this point in the section. */
2671 h->root.u.def.section = s;
2672 h->root.u.def.value = s->_raw_size;
2674 /* Increment the section size to make room for the symbol. */
2675 s->_raw_size += h->size;
2677 return true;
2680 /* Set the sizes of the dynamic sections. */
2682 static boolean
2683 elf32_arm_size_dynamic_sections (output_bfd, info)
2684 bfd * output_bfd;
2685 struct bfd_link_info * info;
2687 bfd * dynobj;
2688 asection * s;
2689 boolean plt;
2690 boolean relocs;
2691 boolean reltext;
2693 dynobj = elf_hash_table (info)->dynobj;
2694 BFD_ASSERT (dynobj != NULL);
2696 if (elf_hash_table (info)->dynamic_sections_created)
2698 /* Set the contents of the .interp section to the interpreter. */
2699 if (! info->shared)
2701 s = bfd_get_section_by_name (dynobj, ".interp");
2702 BFD_ASSERT (s != NULL);
2703 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
2704 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
2707 else
2709 /* We may have created entries in the .rel.got section.
2710 However, if we are not creating the dynamic sections, we will
2711 not actually use these entries. Reset the size of .rel.got,
2712 which will cause it to get stripped from the output file
2713 below. */
2714 s = bfd_get_section_by_name (dynobj, ".rel.got");
2715 if (s != NULL)
2716 s->_raw_size = 0;
2719 /* If this is a -Bsymbolic shared link, then we need to discard all
2720 PC relative relocs against symbols defined in a regular object.
2721 We allocated space for them in the check_relocs routine, but we
2722 will not fill them in in the relocate_section routine. */
2723 if (info->shared && info->symbolic)
2724 elf32_arm_link_hash_traverse (elf32_arm_hash_table (info),
2725 elf32_arm_discard_copies,
2726 (PTR) NULL);
2728 /* The check_relocs and adjust_dynamic_symbol entry points have
2729 determined the sizes of the various dynamic sections. Allocate
2730 memory for them. */
2731 plt = false;
2732 relocs = false;
2733 reltext = false;
2734 for (s = dynobj->sections; s != NULL; s = s->next)
2736 const char * name;
2737 boolean strip;
2739 if ((s->flags & SEC_LINKER_CREATED) == 0)
2740 continue;
2742 /* It's OK to base decisions on the section name, because none
2743 of the dynobj section names depend upon the input files. */
2744 name = bfd_get_section_name (dynobj, s);
2746 strip = false;
2748 if (strcmp (name, ".plt") == 0)
2750 if (s->_raw_size == 0)
2752 /* Strip this section if we don't need it; see the
2753 comment below. */
2754 strip = true;
2756 else
2758 /* Remember whether there is a PLT. */
2759 plt = true;
2762 else if (strncmp (name, ".rel", 4) == 0)
2764 if (s->_raw_size == 0)
2766 /* If we don't need this section, strip it from the
2767 output file. This is mostly to handle .rel.bss and
2768 .rel.plt. We must create both sections in
2769 create_dynamic_sections, because they must be created
2770 before the linker maps input sections to output
2771 sections. The linker does that before
2772 adjust_dynamic_symbol is called, and it is that
2773 function which decides whether anything needs to go
2774 into these sections. */
2775 strip = true;
2777 else
2779 asection * target;
2781 /* Remember whether there are any reloc sections other
2782 than .rel.plt. */
2783 if (strcmp (name, ".rel.plt") != 0)
2785 const char *outname;
2787 relocs = true;
2789 /* If this relocation section applies to a read only
2790 section, then we probably need a DT_TEXTREL
2791 entry. The entries in the .rel.plt section
2792 really apply to the .got section, which we
2793 created ourselves and so know is not readonly. */
2794 outname = bfd_get_section_name (output_bfd,
2795 s->output_section);
2796 target = bfd_get_section_by_name (output_bfd, outname + 4);
2797 if (target != NULL
2798 && (target->flags & SEC_READONLY) != 0
2799 && (target->flags & SEC_ALLOC) != 0)
2800 reltext = true;
2803 /* We use the reloc_count field as a counter if we need
2804 to copy relocs into the output file. */
2805 s->reloc_count = 0;
2808 else if (strncmp (name, ".got", 4) != 0)
2810 /* It's not one of our sections, so don't allocate space. */
2811 continue;
2814 if (strip)
2816 asection ** spp;
2818 for (spp = &s->output_section->owner->sections;
2819 *spp != s->output_section;
2820 spp = &(*spp)->next)
2822 *spp = s->output_section->next;
2823 --s->output_section->owner->section_count;
2825 continue;
2828 /* Allocate memory for the section contents. */
2829 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
2830 if (s->contents == NULL && s->_raw_size != 0)
2831 return false;
2834 if (elf_hash_table (info)->dynamic_sections_created)
2836 /* Add some entries to the .dynamic section. We fill in the
2837 values later, in elf32_arm_finish_dynamic_sections, but we
2838 must add the entries now so that we get the correct size for
2839 the .dynamic section. The DT_DEBUG entry is filled in by the
2840 dynamic linker and used by the debugger. */
2841 if (! info->shared)
2843 if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
2844 return false;
2847 if (plt)
2849 if (! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
2850 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
2851 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
2852 || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
2853 return false;
2856 if (relocs)
2858 if (! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
2859 || ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
2860 || ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
2861 sizeof (Elf32_External_Rel)))
2862 return false;
2865 if (reltext)
2867 if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
2868 return false;
2872 return true;
2875 /* This function is called via elf32_arm_link_hash_traverse if we are
2876 creating a shared object with -Bsymbolic. It discards the space
2877 allocated to copy PC relative relocs against symbols which are
2878 defined in regular objects. We allocated space for them in the
2879 check_relocs routine, but we won't fill them in in the
2880 relocate_section routine. */
2882 static boolean
2883 elf32_arm_discard_copies (h, ignore)
2884 struct elf32_arm_link_hash_entry * h;
2885 PTR ignore ATTRIBUTE_UNUSED;
2887 struct elf32_arm_pcrel_relocs_copied * s;
2889 /* We only discard relocs for symbols defined in a regular object. */
2890 if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2891 return true;
2893 for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
2894 s->section->_raw_size -= s->count * sizeof (Elf32_External_Rel);
2896 return true;
2899 /* Finish up dynamic symbol handling. We set the contents of various
2900 dynamic sections here. */
2902 static boolean
2903 elf32_arm_finish_dynamic_symbol (output_bfd, info, h, sym)
2904 bfd * output_bfd;
2905 struct bfd_link_info * info;
2906 struct elf_link_hash_entry * h;
2907 Elf_Internal_Sym * sym;
2909 bfd * dynobj;
2911 dynobj = elf_hash_table (info)->dynobj;
2913 if (h->plt.offset != (bfd_vma) -1)
2915 asection * splt;
2916 asection * sgot;
2917 asection * srel;
2918 bfd_vma plt_index;
2919 bfd_vma got_offset;
2920 Elf_Internal_Rel rel;
2922 /* This symbol has an entry in the procedure linkage table. Set
2923 it up. */
2925 BFD_ASSERT (h->dynindx != -1);
2927 splt = bfd_get_section_by_name (dynobj, ".plt");
2928 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
2929 srel = bfd_get_section_by_name (dynobj, ".rel.plt");
2930 BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
2932 /* Get the index in the procedure linkage table which
2933 corresponds to this symbol. This is the index of this symbol
2934 in all the symbols for which we are making plt entries. The
2935 first entry in the procedure linkage table is reserved. */
2936 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2938 /* Get the offset into the .got table of the entry that
2939 corresponds to this function. Each .got entry is 4 bytes.
2940 The first three are reserved. */
2941 got_offset = (plt_index + 3) * 4;
2943 /* Fill in the entry in the procedure linkage table. */
2944 memcpy (splt->contents + h->plt.offset,
2945 elf32_arm_plt_entry,
2946 PLT_ENTRY_SIZE);
2947 bfd_put_32 (output_bfd,
2948 (sgot->output_section->vma
2949 + sgot->output_offset
2950 + got_offset
2951 - splt->output_section->vma
2952 - splt->output_offset
2953 - h->plt.offset - 12),
2954 splt->contents + h->plt.offset + 12);
2956 /* Fill in the entry in the global offset table. */
2957 bfd_put_32 (output_bfd,
2958 (splt->output_section->vma
2959 + splt->output_offset),
2960 sgot->contents + got_offset);
2962 /* Fill in the entry in the .rel.plt section. */
2963 rel.r_offset = (sgot->output_section->vma
2964 + sgot->output_offset
2965 + got_offset);
2966 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_JUMP_SLOT);
2967 bfd_elf32_swap_reloc_out (output_bfd, &rel,
2968 ((Elf32_External_Rel *) srel->contents
2969 + plt_index));
2971 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2973 /* Mark the symbol as undefined, rather than as defined in
2974 the .plt section. Leave the value alone. */
2975 sym->st_shndx = SHN_UNDEF;
2979 if (h->got.offset != (bfd_vma) -1)
2981 asection * sgot;
2982 asection * srel;
2983 Elf_Internal_Rel rel;
2985 /* This symbol has an entry in the global offset table. Set it
2986 up. */
2988 sgot = bfd_get_section_by_name (dynobj, ".got");
2989 srel = bfd_get_section_by_name (dynobj, ".rel.got");
2990 BFD_ASSERT (sgot != NULL && srel != NULL);
2992 rel.r_offset = (sgot->output_section->vma
2993 + sgot->output_offset
2994 + (h->got.offset &~ 1));
2996 /* If this is a -Bsymbolic link, and the symbol is defined
2997 locally, we just want to emit a RELATIVE reloc. The entry in
2998 the global offset table will already have been initialized in
2999 the relocate_section function. */
3000 if (info->shared
3001 && (info->symbolic || h->dynindx == -1)
3002 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
3003 rel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
3004 else
3006 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
3007 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_GLOB_DAT);
3010 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3011 ((Elf32_External_Rel *) srel->contents
3012 + srel->reloc_count));
3013 ++srel->reloc_count;
3016 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
3018 asection * s;
3019 Elf_Internal_Rel rel;
3021 /* This symbol needs a copy reloc. Set it up. */
3023 BFD_ASSERT (h->dynindx != -1
3024 && (h->root.type == bfd_link_hash_defined
3025 || h->root.type == bfd_link_hash_defweak));
3027 s = bfd_get_section_by_name (h->root.u.def.section->owner,
3028 ".rel.bss");
3029 BFD_ASSERT (s != NULL);
3031 rel.r_offset = (h->root.u.def.value
3032 + h->root.u.def.section->output_section->vma
3033 + h->root.u.def.section->output_offset);
3034 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_COPY);
3035 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3036 ((Elf32_External_Rel *) s->contents
3037 + s->reloc_count));
3038 ++s->reloc_count;
3041 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3042 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3043 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
3044 sym->st_shndx = SHN_ABS;
3046 return true;
3049 /* Finish up the dynamic sections. */
3051 static boolean
3052 elf32_arm_finish_dynamic_sections (output_bfd, info)
3053 bfd * output_bfd;
3054 struct bfd_link_info * info;
3056 bfd * dynobj;
3057 asection * sgot;
3058 asection * sdyn;
3060 dynobj = elf_hash_table (info)->dynobj;
3062 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
3063 BFD_ASSERT (sgot != NULL);
3064 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3066 if (elf_hash_table (info)->dynamic_sections_created)
3068 asection *splt;
3069 Elf32_External_Dyn *dyncon, *dynconend;
3071 splt = bfd_get_section_by_name (dynobj, ".plt");
3072 BFD_ASSERT (splt != NULL && sdyn != NULL);
3074 dyncon = (Elf32_External_Dyn *) sdyn->contents;
3075 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
3076 for (; dyncon < dynconend; dyncon++)
3078 Elf_Internal_Dyn dyn;
3079 const char * name;
3080 asection * s;
3082 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
3084 switch (dyn.d_tag)
3086 default:
3087 break;
3089 case DT_PLTGOT:
3090 name = ".got";
3091 goto get_vma;
3092 case DT_JMPREL:
3093 name = ".rel.plt";
3094 get_vma:
3095 s = bfd_get_section_by_name (output_bfd, name);
3096 BFD_ASSERT (s != NULL);
3097 dyn.d_un.d_ptr = s->vma;
3098 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3099 break;
3101 case DT_PLTRELSZ:
3102 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3103 BFD_ASSERT (s != NULL);
3104 if (s->_cooked_size != 0)
3105 dyn.d_un.d_val = s->_cooked_size;
3106 else
3107 dyn.d_un.d_val = s->_raw_size;
3108 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3109 break;
3111 case DT_RELSZ:
3112 /* My reading of the SVR4 ABI indicates that the
3113 procedure linkage table relocs (DT_JMPREL) should be
3114 included in the overall relocs (DT_REL). This is
3115 what Solaris does. However, UnixWare can not handle
3116 that case. Therefore, we override the DT_RELSZ entry
3117 here to make it not include the JMPREL relocs. Since
3118 the linker script arranges for .rel.plt to follow all
3119 other relocation sections, we don't have to worry
3120 about changing the DT_REL entry. */
3121 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3122 if (s != NULL)
3124 if (s->_cooked_size != 0)
3125 dyn.d_un.d_val -= s->_cooked_size;
3126 else
3127 dyn.d_un.d_val -= s->_raw_size;
3129 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3130 break;
3134 /* Fill in the first entry in the procedure linkage table. */
3135 if (splt->_raw_size > 0)
3136 memcpy (splt->contents, elf32_arm_plt0_entry, PLT_ENTRY_SIZE);
3138 /* UnixWare sets the entsize of .plt to 4, although that doesn't
3139 really seem like the right value. */
3140 elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
3143 /* Fill in the first three entries in the global offset table. */
3144 if (sgot->_raw_size > 0)
3146 if (sdyn == NULL)
3147 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
3148 else
3149 bfd_put_32 (output_bfd,
3150 sdyn->output_section->vma + sdyn->output_offset,
3151 sgot->contents);
3152 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
3153 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
3156 elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
3158 return true;
3161 static void
3162 elf32_arm_post_process_headers (abfd, link_info)
3163 bfd * abfd;
3164 struct bfd_link_info * link_info ATTRIBUTE_UNUSED;
3166 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
3168 i_ehdrp = elf_elfheader (abfd);
3170 i_ehdrp->e_ident[EI_OSABI] = ARM_ELF_OS_ABI_VERSION;
3171 i_ehdrp->e_ident[EI_ABIVERSION] = ARM_ELF_ABI_VERSION;
3175 #define ELF_ARCH bfd_arch_arm
3176 #define ELF_MACHINE_CODE EM_ARM
3177 #define ELF_MAXPAGESIZE 0x8000
3180 #define bfd_elf32_bfd_copy_private_bfd_data elf32_arm_copy_private_bfd_data
3181 #define bfd_elf32_bfd_merge_private_bfd_data elf32_arm_merge_private_bfd_data
3182 #define bfd_elf32_bfd_set_private_flags elf32_arm_set_private_flags
3183 #define bfd_elf32_bfd_print_private_bfd_data elf32_arm_print_private_bfd_data
3184 #define bfd_elf32_bfd_link_hash_table_create elf32_arm_link_hash_table_create
3185 #define bfd_elf32_bfd_reloc_type_lookup elf32_arm_reloc_type_lookup
3186 #define bfd_elf32_find_nearest_line elf32_arm_find_nearest_line
3188 #define elf_backend_get_symbol_type elf32_arm_get_symbol_type
3189 #define elf_backend_gc_mark_hook elf32_arm_gc_mark_hook
3190 #define elf_backend_gc_sweep_hook elf32_arm_gc_sweep_hook
3191 #define elf_backend_check_relocs elf32_arm_check_relocs
3192 #define elf_backend_relocate_section elf32_arm_relocate_section
3193 #define elf_backend_adjust_dynamic_symbol elf32_arm_adjust_dynamic_symbol
3194 #define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
3195 #define elf_backend_finish_dynamic_symbol elf32_arm_finish_dynamic_symbol
3196 #define elf_backend_finish_dynamic_sections elf32_arm_finish_dynamic_sections
3197 #define elf_backend_size_dynamic_sections elf32_arm_size_dynamic_sections
3198 #define elf_backend_post_process_headers elf32_arm_post_process_headers
3200 #define elf_backend_can_gc_sections 1
3201 #define elf_backend_plt_readonly 1
3202 #define elf_backend_want_got_plt 1
3203 #define elf_backend_want_plt_sym 0
3205 #define elf_backend_got_header_size 12
3206 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
3208 #include "elf32-target.h"