2001-06-09 Philip Blundell <philb@gnu.org>
[binutils.git] / bfd / elf32-arm.h
blob6fb163389ac1fee808e2a5904ecc44479ad69f1b
1 /* 32-bit ELF support for ARM
2 Copyright 1998, 1999, 2000, 2001 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. */
20 typedef unsigned long int insn32;
21 typedef unsigned short int insn16;
23 static boolean elf32_arm_set_private_flags
24 PARAMS ((bfd *, flagword));
25 static boolean elf32_arm_copy_private_bfd_data
26 PARAMS ((bfd *, bfd *));
27 static boolean elf32_arm_merge_private_bfd_data
28 PARAMS ((bfd *, bfd *));
29 static boolean elf32_arm_print_private_bfd_data
30 PARAMS ((bfd *, PTR));
31 static int elf32_arm_get_symbol_type
32 PARAMS (( Elf_Internal_Sym *, int));
33 static struct bfd_link_hash_table *elf32_arm_link_hash_table_create
34 PARAMS ((bfd *));
35 static bfd_reloc_status_type elf32_arm_final_link_relocate
36 PARAMS ((reloc_howto_type *, bfd *, bfd *, asection *, bfd_byte *,
37 Elf_Internal_Rela *, bfd_vma, struct bfd_link_info *, asection *,
38 const char *, unsigned char, struct elf_link_hash_entry *));
39 static insn32 insert_thumb_branch
40 PARAMS ((insn32, int));
41 static struct elf_link_hash_entry *find_thumb_glue
42 PARAMS ((struct bfd_link_info *, CONST char *, bfd *));
43 static struct elf_link_hash_entry *find_arm_glue
44 PARAMS ((struct bfd_link_info *, CONST char *, bfd *));
45 static void record_arm_to_thumb_glue
46 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
47 static void record_thumb_to_arm_glue
48 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
49 static void elf32_arm_post_process_headers
50 PARAMS ((bfd *, struct bfd_link_info *));
51 static int elf32_arm_to_thumb_stub
52 PARAMS ((struct bfd_link_info *, const char *, bfd *, bfd *, asection *,
53 bfd_byte *, asection *, bfd_vma, bfd_signed_vma, bfd_vma));
54 static int elf32_thumb_to_arm_stub
55 PARAMS ((struct bfd_link_info *, const char *, bfd *, bfd *, asection *,
56 bfd_byte *, asection *, bfd_vma, bfd_signed_vma, bfd_vma));
58 #define INTERWORK_FLAG(abfd) (elf_elfheader (abfd)->e_flags & EF_ARM_INTERWORK)
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. */
64 #define THUMB2ARM_GLUE_SECTION_NAME ".glue_7t"
65 #define THUMB2ARM_GLUE_ENTRY_NAME "__%s_from_thumb"
67 #define ARM2THUMB_GLUE_SECTION_NAME ".glue_7"
68 #define ARM2THUMB_GLUE_ENTRY_NAME "__%s_from_arm"
70 /* The name of the dynamic interpreter. This is put in the .interp
71 section. */
72 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/ld.so.1"
74 /* The size in bytes of an entry in the procedure linkage table. */
75 #define PLT_ENTRY_SIZE 16
77 /* The first entry in a procedure linkage table looks like
78 this. It is set up so that any shared library function that is
79 called before the relocation has been set up calls the dynamic
80 linker first. */
81 static const unsigned long elf32_arm_plt0_entry [PLT_ENTRY_SIZE / 4] =
83 0xe52de004, /* str lr, [sp, #-4]! */
84 0xe59fe010, /* ldr lr, [pc, #16] */
85 0xe08fe00e, /* add lr, pc, lr */
86 0xe5bef008 /* ldr pc, [lr, #8]! */
89 /* Subsequent entries in a procedure linkage table look like
90 this. */
91 static const unsigned long elf32_arm_plt_entry [PLT_ENTRY_SIZE / 4] =
93 0xe59fc004, /* ldr ip, [pc, #4] */
94 0xe08fc00c, /* add ip, pc, ip */
95 0xe59cf000, /* ldr pc, [ip] */
96 0x00000000 /* offset to symbol in got */
99 /* The ARM linker needs to keep track of the number of relocs that it
100 decides to copy in check_relocs for each symbol. This is so that
101 it can discard PC relative relocs if it doesn't need them when
102 linking with -Bsymbolic. We store the information in a field
103 extending the regular ELF linker hash table. */
105 /* This structure keeps track of the number of PC relative relocs we
106 have copied for a given symbol. */
107 struct elf32_arm_pcrel_relocs_copied
109 /* Next section. */
110 struct elf32_arm_pcrel_relocs_copied * next;
111 /* A section in dynobj. */
112 asection * section;
113 /* Number of relocs copied in this section. */
114 bfd_size_type count;
117 /* Arm ELF linker hash entry. */
118 struct elf32_arm_link_hash_entry
120 struct elf_link_hash_entry root;
122 /* Number of PC relative relocs copied for this symbol. */
123 struct elf32_arm_pcrel_relocs_copied * pcrel_relocs_copied;
126 /* Declare this now that the above structures are defined. */
127 static boolean elf32_arm_discard_copies
128 PARAMS ((struct elf32_arm_link_hash_entry *, PTR));
130 /* Traverse an arm ELF linker hash table. */
131 #define elf32_arm_link_hash_traverse(table, func, info) \
132 (elf_link_hash_traverse \
133 (&(table)->root, \
134 (boolean (*) PARAMS ((struct elf_link_hash_entry *, PTR))) (func), \
135 (info)))
137 /* Get the ARM elf linker hash table from a link_info structure. */
138 #define elf32_arm_hash_table(info) \
139 ((struct elf32_arm_link_hash_table *) ((info)->hash))
141 /* ARM ELF linker hash table. */
142 struct elf32_arm_link_hash_table
144 /* The main hash table. */
145 struct elf_link_hash_table root;
147 /* The size in bytes of the section containg the Thumb-to-ARM glue. */
148 long int thumb_glue_size;
150 /* The size in bytes of the section containg the ARM-to-Thumb glue. */
151 long int arm_glue_size;
153 /* An arbitary input BFD chosen to hold the glue sections. */
154 bfd * bfd_of_glue_owner;
156 /* A boolean indicating whether knowledge of the ARM's pipeline
157 length should be applied by the linker. */
158 int no_pipeline_knowledge;
161 /* Create an entry in an ARM ELF linker hash table. */
163 static struct bfd_hash_entry *
164 elf32_arm_link_hash_newfunc (entry, table, string)
165 struct bfd_hash_entry * entry;
166 struct bfd_hash_table * table;
167 const char * string;
169 struct elf32_arm_link_hash_entry * ret =
170 (struct elf32_arm_link_hash_entry *) entry;
172 /* Allocate the structure if it has not already been allocated by a
173 subclass. */
174 if (ret == (struct elf32_arm_link_hash_entry *) NULL)
175 ret = ((struct elf32_arm_link_hash_entry *)
176 bfd_hash_allocate (table,
177 sizeof (struct elf32_arm_link_hash_entry)));
178 if (ret == (struct elf32_arm_link_hash_entry *) NULL)
179 return (struct bfd_hash_entry *) ret;
181 /* Call the allocation method of the superclass. */
182 ret = ((struct elf32_arm_link_hash_entry *)
183 _bfd_elf_link_hash_newfunc ((struct bfd_hash_entry *) ret,
184 table, string));
185 if (ret != (struct elf32_arm_link_hash_entry *) NULL)
186 ret->pcrel_relocs_copied = NULL;
188 return (struct bfd_hash_entry *) ret;
191 /* Create an ARM elf linker hash table. */
193 static struct bfd_link_hash_table *
194 elf32_arm_link_hash_table_create (abfd)
195 bfd *abfd;
197 struct elf32_arm_link_hash_table *ret;
199 ret = ((struct elf32_arm_link_hash_table *)
200 bfd_alloc (abfd, sizeof (struct elf32_arm_link_hash_table)));
201 if (ret == (struct elf32_arm_link_hash_table *) NULL)
202 return NULL;
204 if (!_bfd_elf_link_hash_table_init (&ret->root, abfd,
205 elf32_arm_link_hash_newfunc))
207 bfd_release (abfd, ret);
208 return NULL;
211 ret->thumb_glue_size = 0;
212 ret->arm_glue_size = 0;
213 ret->bfd_of_glue_owner = NULL;
214 ret->no_pipeline_knowledge = 0;
216 return &ret->root.root;
219 /* Locate the Thumb encoded calling stub for NAME. */
221 static struct elf_link_hash_entry *
222 find_thumb_glue (link_info, name, input_bfd)
223 struct bfd_link_info *link_info;
224 CONST char *name;
225 bfd *input_bfd;
227 char *tmp_name;
228 struct elf_link_hash_entry *hash;
229 struct elf32_arm_link_hash_table *hash_table;
231 /* We need a pointer to the armelf specific hash table. */
232 hash_table = elf32_arm_hash_table (link_info);
234 tmp_name = ((char *)
235 bfd_malloc (strlen (name) + strlen (THUMB2ARM_GLUE_ENTRY_NAME) + 1));
237 BFD_ASSERT (tmp_name);
239 sprintf (tmp_name, THUMB2ARM_GLUE_ENTRY_NAME, name);
241 hash = elf_link_hash_lookup
242 (&(hash_table)->root, tmp_name, false, false, true);
244 if (hash == NULL)
245 /* xgettext:c-format */
246 _bfd_error_handler (_("%s: unable to find THUMB glue '%s' for `%s'"),
247 bfd_get_filename (input_bfd), tmp_name, name);
249 free (tmp_name);
251 return hash;
254 /* Locate the ARM encoded calling stub for NAME. */
256 static struct elf_link_hash_entry *
257 find_arm_glue (link_info, name, input_bfd)
258 struct bfd_link_info *link_info;
259 CONST char *name;
260 bfd *input_bfd;
262 char *tmp_name;
263 struct elf_link_hash_entry *myh;
264 struct elf32_arm_link_hash_table *hash_table;
266 /* We need a pointer to the elfarm specific hash table. */
267 hash_table = elf32_arm_hash_table (link_info);
269 tmp_name = ((char *)
270 bfd_malloc (strlen (name) + strlen (ARM2THUMB_GLUE_ENTRY_NAME) + 1));
272 BFD_ASSERT (tmp_name);
274 sprintf (tmp_name, ARM2THUMB_GLUE_ENTRY_NAME, name);
276 myh = elf_link_hash_lookup
277 (&(hash_table)->root, tmp_name, false, false, true);
279 if (myh == NULL)
280 /* xgettext:c-format */
281 _bfd_error_handler (_("%s: unable to find ARM glue '%s' for `%s'"),
282 bfd_get_filename (input_bfd), tmp_name, name);
284 free (tmp_name);
286 return myh;
289 /* ARM->Thumb glue:
291 .arm
292 __func_from_arm:
293 ldr r12, __func_addr
294 bx r12
295 __func_addr:
296 .word func @ behave as if you saw a ARM_32 reloc. */
298 #define ARM2THUMB_GLUE_SIZE 12
299 static const insn32 a2t1_ldr_insn = 0xe59fc000;
300 static const insn32 a2t2_bx_r12_insn = 0xe12fff1c;
301 static const insn32 a2t3_func_addr_insn = 0x00000001;
303 /* Thumb->ARM: Thumb->(non-interworking aware) ARM
305 .thumb .thumb
306 .align 2 .align 2
307 __func_from_thumb: __func_from_thumb:
308 bx pc push {r6, lr}
309 nop ldr r6, __func_addr
310 .arm mov lr, pc
311 __func_change_to_arm: bx r6
312 b func .arm
313 __func_back_to_thumb:
314 ldmia r13! {r6, lr}
315 bx lr
316 __func_addr:
317 .word func */
319 #define THUMB2ARM_GLUE_SIZE 8
320 static const insn16 t2a1_bx_pc_insn = 0x4778;
321 static const insn16 t2a2_noop_insn = 0x46c0;
322 static const insn32 t2a3_b_insn = 0xea000000;
324 static const insn16 t2a1_push_insn = 0xb540;
325 static const insn16 t2a2_ldr_insn = 0x4e03;
326 static const insn16 t2a3_mov_insn = 0x46fe;
327 static const insn16 t2a4_bx_insn = 0x4730;
328 static const insn32 t2a5_pop_insn = 0xe8bd4040;
329 static const insn32 t2a6_bx_insn = 0xe12fff1e;
331 boolean
332 bfd_elf32_arm_allocate_interworking_sections (info)
333 struct bfd_link_info * info;
335 asection * s;
336 bfd_byte * foo;
337 struct elf32_arm_link_hash_table * globals;
339 globals = elf32_arm_hash_table (info);
341 BFD_ASSERT (globals != NULL);
343 if (globals->arm_glue_size != 0)
345 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
347 s = bfd_get_section_by_name
348 (globals->bfd_of_glue_owner, ARM2THUMB_GLUE_SECTION_NAME);
350 BFD_ASSERT (s != NULL);
352 foo = (bfd_byte *) bfd_alloc
353 (globals->bfd_of_glue_owner, globals->arm_glue_size);
355 s->_raw_size = s->_cooked_size = globals->arm_glue_size;
356 s->contents = foo;
359 if (globals->thumb_glue_size != 0)
361 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
363 s = bfd_get_section_by_name
364 (globals->bfd_of_glue_owner, THUMB2ARM_GLUE_SECTION_NAME);
366 BFD_ASSERT (s != NULL);
368 foo = (bfd_byte *) bfd_alloc
369 (globals->bfd_of_glue_owner, globals->thumb_glue_size);
371 s->_raw_size = s->_cooked_size = globals->thumb_glue_size;
372 s->contents = foo;
375 return true;
378 static void
379 record_arm_to_thumb_glue (link_info, h)
380 struct bfd_link_info * link_info;
381 struct elf_link_hash_entry * h;
383 const char * name = h->root.root.string;
384 register asection * s;
385 char * tmp_name;
386 struct elf_link_hash_entry * myh;
387 struct elf32_arm_link_hash_table * globals;
389 globals = elf32_arm_hash_table (link_info);
391 BFD_ASSERT (globals != NULL);
392 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
394 s = bfd_get_section_by_name
395 (globals->bfd_of_glue_owner, ARM2THUMB_GLUE_SECTION_NAME);
397 BFD_ASSERT (s != NULL);
399 tmp_name = ((char *)
400 bfd_malloc (strlen (name) + strlen (ARM2THUMB_GLUE_ENTRY_NAME) + 1));
402 BFD_ASSERT (tmp_name);
404 sprintf (tmp_name, ARM2THUMB_GLUE_ENTRY_NAME, name);
406 myh = elf_link_hash_lookup
407 (&(globals)->root, tmp_name, false, false, true);
409 if (myh != NULL)
411 /* We've already seen this guy. */
412 free (tmp_name);
413 return;
416 /* The only trick here is using hash_table->arm_glue_size as the value. Even
417 though the section isn't allocated yet, this is where we will be putting
418 it. */
419 _bfd_generic_link_add_one_symbol (link_info, globals->bfd_of_glue_owner, tmp_name,
420 BSF_GLOBAL,
421 s, globals->arm_glue_size + 1,
422 NULL, true, false,
423 (struct bfd_link_hash_entry **) &myh);
425 free (tmp_name);
427 globals->arm_glue_size += ARM2THUMB_GLUE_SIZE;
429 return;
432 static void
433 record_thumb_to_arm_glue (link_info, h)
434 struct bfd_link_info *link_info;
435 struct elf_link_hash_entry *h;
437 const char *name = h->root.root.string;
438 register asection *s;
439 char *tmp_name;
440 struct elf_link_hash_entry *myh;
441 struct elf32_arm_link_hash_table *hash_table;
442 char bind;
444 hash_table = elf32_arm_hash_table (link_info);
446 BFD_ASSERT (hash_table != NULL);
447 BFD_ASSERT (hash_table->bfd_of_glue_owner != NULL);
449 s = bfd_get_section_by_name
450 (hash_table->bfd_of_glue_owner, THUMB2ARM_GLUE_SECTION_NAME);
452 BFD_ASSERT (s != NULL);
454 tmp_name = (char *) bfd_malloc (strlen (name) + strlen (THUMB2ARM_GLUE_ENTRY_NAME) + 1);
456 BFD_ASSERT (tmp_name);
458 sprintf (tmp_name, THUMB2ARM_GLUE_ENTRY_NAME, name);
460 myh = elf_link_hash_lookup
461 (&(hash_table)->root, tmp_name, false, false, true);
463 if (myh != NULL)
465 /* We've already seen this guy. */
466 free (tmp_name);
467 return;
470 _bfd_generic_link_add_one_symbol (link_info, hash_table->bfd_of_glue_owner, tmp_name,
471 BSF_GLOBAL, s, hash_table->thumb_glue_size + 1,
472 NULL, true, false,
473 (struct bfd_link_hash_entry **) &myh);
475 /* If we mark it 'Thumb', the disassembler will do a better job. */
476 bind = ELF_ST_BIND (myh->type);
477 myh->type = ELF_ST_INFO (bind, STT_ARM_TFUNC);
479 free (tmp_name);
481 #define CHANGE_TO_ARM "__%s_change_to_arm"
482 #define BACK_FROM_ARM "__%s_back_from_arm"
484 /* Allocate another symbol to mark where we switch to Arm mode. */
485 tmp_name = (char *) bfd_malloc (strlen (name) + strlen (CHANGE_TO_ARM) + 1);
487 BFD_ASSERT (tmp_name);
489 sprintf (tmp_name, CHANGE_TO_ARM, name);
491 myh = NULL;
493 _bfd_generic_link_add_one_symbol (link_info, hash_table->bfd_of_glue_owner, tmp_name,
494 BSF_LOCAL, s, hash_table->thumb_glue_size + 4,
495 NULL, true, false,
496 (struct bfd_link_hash_entry **) &myh);
498 free (tmp_name);
500 hash_table->thumb_glue_size += THUMB2ARM_GLUE_SIZE;
502 return;
505 /* Select a BFD to be used to hold the sections used by the glue code.
506 This function is called from the linker scripts in ld/emultempl/
507 {armelf/pe}.em */
509 boolean
510 bfd_elf32_arm_get_bfd_for_interworking (abfd, info)
511 bfd *abfd;
512 struct bfd_link_info *info;
514 struct elf32_arm_link_hash_table *globals;
515 flagword flags;
516 asection *sec;
518 /* If we are only performing a partial link do not bother
519 getting a bfd to hold the glue. */
520 if (info->relocateable)
521 return true;
523 globals = elf32_arm_hash_table (info);
525 BFD_ASSERT (globals != NULL);
527 if (globals->bfd_of_glue_owner != NULL)
528 return true;
530 sec = bfd_get_section_by_name (abfd, ARM2THUMB_GLUE_SECTION_NAME);
532 if (sec == NULL)
534 /* Note: we do not include the flag SEC_LINKER_CREATED, as this
535 will prevent elf_link_input_bfd() from processing the contents
536 of this section. */
537 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_CODE | SEC_READONLY;
539 sec = bfd_make_section (abfd, ARM2THUMB_GLUE_SECTION_NAME);
541 if (sec == NULL
542 || !bfd_set_section_flags (abfd, sec, flags)
543 || !bfd_set_section_alignment (abfd, sec, 2))
544 return false;
546 /* Set the gc mark to prevent the section from being removed by garbage
547 collection, despite the fact that no relocs refer to this section. */
548 sec->gc_mark = 1;
551 sec = bfd_get_section_by_name (abfd, THUMB2ARM_GLUE_SECTION_NAME);
553 if (sec == NULL)
555 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_CODE | SEC_READONLY;
557 sec = bfd_make_section (abfd, THUMB2ARM_GLUE_SECTION_NAME);
559 if (sec == NULL
560 || !bfd_set_section_flags (abfd, sec, flags)
561 || !bfd_set_section_alignment (abfd, sec, 2))
562 return false;
564 sec->gc_mark = 1;
567 /* Save the bfd for later use. */
568 globals->bfd_of_glue_owner = abfd;
570 return true;
573 boolean
574 bfd_elf32_arm_process_before_allocation (abfd, link_info, no_pipeline_knowledge)
575 bfd *abfd;
576 struct bfd_link_info *link_info;
577 int no_pipeline_knowledge;
579 Elf_Internal_Shdr *symtab_hdr;
580 Elf_Internal_Rela *free_relocs = NULL;
581 Elf_Internal_Rela *irel, *irelend;
582 bfd_byte *contents = NULL;
583 bfd_byte *free_contents = NULL;
584 Elf32_External_Sym *extsyms = NULL;
585 Elf32_External_Sym *free_extsyms = NULL;
587 asection *sec;
588 struct elf32_arm_link_hash_table *globals;
590 /* If we are only performing a partial link do not bother
591 to construct any glue. */
592 if (link_info->relocateable)
593 return true;
595 /* Here we have a bfd that is to be included on the link. We have a hook
596 to do reloc rummaging, before section sizes are nailed down. */
597 globals = elf32_arm_hash_table (link_info);
599 BFD_ASSERT (globals != NULL);
600 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
602 globals->no_pipeline_knowledge = no_pipeline_knowledge;
604 /* Rummage around all the relocs and map the glue vectors. */
605 sec = abfd->sections;
607 if (sec == NULL)
608 return true;
610 for (; sec != NULL; sec = sec->next)
612 if (sec->reloc_count == 0)
613 continue;
615 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
617 /* Load the relocs. */
618 irel = (_bfd_elf32_link_read_relocs (abfd, sec, (PTR) NULL,
619 (Elf_Internal_Rela *) NULL, false));
621 BFD_ASSERT (irel != 0);
623 irelend = irel + sec->reloc_count;
624 for (; irel < irelend; irel++)
626 long r_type;
627 unsigned long r_index;
629 struct elf_link_hash_entry *h;
631 r_type = ELF32_R_TYPE (irel->r_info);
632 r_index = ELF32_R_SYM (irel->r_info);
634 /* These are the only relocation types we care about. */
635 if ( r_type != R_ARM_PC24
636 && r_type != R_ARM_THM_PC22)
637 continue;
639 /* Get the section contents if we haven't done so already. */
640 if (contents == NULL)
642 /* Get cached copy if it exists. */
643 if (elf_section_data (sec)->this_hdr.contents != NULL)
644 contents = elf_section_data (sec)->this_hdr.contents;
645 else
647 /* Go get them off disk. */
648 contents = (bfd_byte *) bfd_malloc (sec->_raw_size);
649 if (contents == NULL)
650 goto error_return;
652 free_contents = contents;
654 if (!bfd_get_section_contents (abfd, sec, contents,
655 (file_ptr) 0, sec->_raw_size))
656 goto error_return;
660 /* Read this BFD's symbols if we haven't done so already. */
661 if (extsyms == NULL)
663 /* Get cached copy if it exists. */
664 if (symtab_hdr->contents != NULL)
665 extsyms = (Elf32_External_Sym *) symtab_hdr->contents;
666 else
668 /* Go get them off disk. */
669 extsyms = ((Elf32_External_Sym *)
670 bfd_malloc (symtab_hdr->sh_size));
671 if (extsyms == NULL)
672 goto error_return;
674 free_extsyms = extsyms;
676 if (bfd_seek (abfd, symtab_hdr->sh_offset, SEEK_SET) != 0
677 || (bfd_read (extsyms, 1, symtab_hdr->sh_size, abfd)
678 != symtab_hdr->sh_size))
679 goto error_return;
683 /* If the relocation is not against a symbol it cannot concern us. */
684 h = NULL;
686 /* We don't care about local symbols. */
687 if (r_index < symtab_hdr->sh_info)
688 continue;
690 /* This is an external symbol. */
691 r_index -= symtab_hdr->sh_info;
692 h = (struct elf_link_hash_entry *)
693 elf_sym_hashes (abfd)[r_index];
695 /* If the relocation is against a static symbol it must be within
696 the current section and so cannot be a cross ARM/Thumb relocation. */
697 if (h == NULL)
698 continue;
700 switch (r_type)
702 case R_ARM_PC24:
703 /* This one is a call from arm code. We need to look up
704 the target of the call. If it is a thumb target, we
705 insert glue. */
706 if (ELF_ST_TYPE(h->type) == STT_ARM_TFUNC)
707 record_arm_to_thumb_glue (link_info, h);
708 break;
710 case R_ARM_THM_PC22:
711 /* This one is a call from thumb code. We look
712 up the target of the call. If it is not a thumb
713 target, we insert glue. */
714 if (ELF_ST_TYPE (h->type) != STT_ARM_TFUNC)
715 record_thumb_to_arm_glue (link_info, h);
716 break;
718 default:
719 break;
724 return true;
726 error_return:
727 if (free_relocs != NULL)
728 free (free_relocs);
729 if (free_contents != NULL)
730 free (free_contents);
731 if (free_extsyms != NULL)
732 free (free_extsyms);
734 return false;
737 /* The thumb form of a long branch is a bit finicky, because the offset
738 encoding is split over two fields, each in it's own instruction. They
739 can occur in any order. So given a thumb form of long branch, and an
740 offset, insert the offset into the thumb branch and return finished
741 instruction.
743 It takes two thumb instructions to encode the target address. Each has
744 11 bits to invest. The upper 11 bits are stored in one (identifed by
745 H-0.. see below), the lower 11 bits are stored in the other (identified
746 by H-1).
748 Combine together and shifted left by 1 (it's a half word address) and
749 there you have it.
751 Op: 1111 = F,
752 H-0, upper address-0 = 000
753 Op: 1111 = F,
754 H-1, lower address-0 = 800
756 They can be ordered either way, but the arm tools I've seen always put
757 the lower one first. It probably doesn't matter. krk@cygnus.com
759 XXX: Actually the order does matter. The second instruction (H-1)
760 moves the computed address into the PC, so it must be the second one
761 in the sequence. The problem, however is that whilst little endian code
762 stores the instructions in HI then LOW order, big endian code does the
763 reverse. nickc@cygnus.com. */
765 #define LOW_HI_ORDER 0xF800F000
766 #define HI_LOW_ORDER 0xF000F800
768 static insn32
769 insert_thumb_branch (br_insn, rel_off)
770 insn32 br_insn;
771 int rel_off;
773 unsigned int low_bits;
774 unsigned int high_bits;
776 BFD_ASSERT ((rel_off & 1) != 1);
778 rel_off >>= 1; /* Half word aligned address. */
779 low_bits = rel_off & 0x000007FF; /* The bottom 11 bits. */
780 high_bits = (rel_off >> 11) & 0x000007FF; /* The top 11 bits. */
782 if ((br_insn & LOW_HI_ORDER) == LOW_HI_ORDER)
783 br_insn = LOW_HI_ORDER | (low_bits << 16) | high_bits;
784 else if ((br_insn & HI_LOW_ORDER) == HI_LOW_ORDER)
785 br_insn = HI_LOW_ORDER | (high_bits << 16) | low_bits;
786 else
787 /* FIXME: abort is probably not the right call. krk@cygnus.com */
788 abort (); /* error - not a valid branch instruction form. */
790 return br_insn;
793 /* Thumb code calling an ARM function. */
795 static int
796 elf32_thumb_to_arm_stub (info, name, input_bfd, output_bfd, input_section,
797 hit_data, sym_sec, offset, addend, val)
798 struct bfd_link_info * info;
799 const char * name;
800 bfd * input_bfd;
801 bfd * output_bfd;
802 asection * input_section;
803 bfd_byte * hit_data;
804 asection * sym_sec;
805 bfd_vma offset;
806 bfd_signed_vma addend;
807 bfd_vma val;
809 asection * s = 0;
810 long int my_offset;
811 unsigned long int tmp;
812 long int ret_offset;
813 struct elf_link_hash_entry * myh;
814 struct elf32_arm_link_hash_table * globals;
816 myh = find_thumb_glue (info, name, input_bfd);
817 if (myh == NULL)
818 return false;
820 globals = elf32_arm_hash_table (info);
822 BFD_ASSERT (globals != NULL);
823 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
825 my_offset = myh->root.u.def.value;
827 s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
828 THUMB2ARM_GLUE_SECTION_NAME);
830 BFD_ASSERT (s != NULL);
831 BFD_ASSERT (s->contents != NULL);
832 BFD_ASSERT (s->output_section != NULL);
834 if ((my_offset & 0x01) == 0x01)
836 if (sym_sec != NULL
837 && sym_sec->owner != NULL
838 && !INTERWORK_FLAG (sym_sec->owner))
840 _bfd_error_handler
841 (_("%s(%s): warning: interworking not enabled."),
842 bfd_get_filename (sym_sec->owner), name);
843 _bfd_error_handler
844 (_(" first occurrence: %s: thumb call to arm"),
845 bfd_get_filename (input_bfd));
847 return false;
850 --my_offset;
851 myh->root.u.def.value = my_offset;
853 bfd_put_16 (output_bfd, t2a1_bx_pc_insn,
854 s->contents + my_offset);
856 bfd_put_16 (output_bfd, t2a2_noop_insn,
857 s->contents + my_offset + 2);
859 ret_offset =
860 /* Address of destination of the stub. */
861 ((bfd_signed_vma) val)
862 - ((bfd_signed_vma)
863 /* Offset from the start of the current section to the start of the stubs. */
864 (s->output_offset
865 /* Offset of the start of this stub from the start of the stubs. */
866 + my_offset
867 /* Address of the start of the current section. */
868 + s->output_section->vma)
869 /* The branch instruction is 4 bytes into the stub. */
871 /* ARM branches work from the pc of the instruction + 8. */
872 + 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 - 8;
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. */
902 static int
903 elf32_arm_to_thumb_stub (info, name, input_bfd, output_bfd, input_section,
904 hit_data, sym_sec, offset, addend, val)
905 struct bfd_link_info * info;
906 const char * name;
907 bfd * input_bfd;
908 bfd * output_bfd;
909 asection * input_section;
910 bfd_byte * hit_data;
911 asection * sym_sec;
912 bfd_vma offset;
913 bfd_signed_vma addend;
914 bfd_vma val;
916 unsigned long int tmp;
917 long int my_offset;
918 asection * s;
919 long int ret_offset;
920 struct elf_link_hash_entry * myh;
921 struct elf32_arm_link_hash_table * globals;
923 myh = find_arm_glue (info, name, input_bfd);
924 if (myh == NULL)
925 return false;
927 globals = elf32_arm_hash_table (info);
929 BFD_ASSERT (globals != NULL);
930 BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
932 my_offset = myh->root.u.def.value;
933 s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
934 ARM2THUMB_GLUE_SECTION_NAME);
935 BFD_ASSERT (s != NULL);
936 BFD_ASSERT (s->contents != NULL);
937 BFD_ASSERT (s->output_section != NULL);
939 if ((my_offset & 0x01) == 0x01)
941 if (sym_sec != NULL
942 && sym_sec->owner != NULL
943 && !INTERWORK_FLAG (sym_sec->owner))
945 _bfd_error_handler
946 (_("%s(%s): warning: interworking not enabled."),
947 bfd_get_filename (sym_sec->owner), name);
948 _bfd_error_handler
949 (_(" first occurrence: %s: arm call to thumb"),
950 bfd_get_filename (input_bfd));
953 --my_offset;
954 myh->root.u.def.value = my_offset;
956 bfd_put_32 (output_bfd, a2t1_ldr_insn,
957 s->contents + my_offset);
959 bfd_put_32 (output_bfd, a2t2_bx_r12_insn,
960 s->contents + my_offset + 4);
962 /* It's a thumb address. Add the low order bit. */
963 bfd_put_32 (output_bfd, val | a2t3_func_addr_insn,
964 s->contents + my_offset + 8);
967 BFD_ASSERT (my_offset <= globals->arm_glue_size);
969 tmp = bfd_get_32 (input_bfd, hit_data);
970 tmp = tmp & 0xFF000000;
972 /* Somehow these are both 4 too far, so subtract 8. */
973 ret_offset = s->output_offset
974 + my_offset
975 + s->output_section->vma
976 - (input_section->output_offset
977 + input_section->output_section->vma
978 + offset + addend)
979 - 8;
981 tmp = tmp | ((ret_offset >> 2) & 0x00FFFFFF);
983 bfd_put_32 (output_bfd, tmp, hit_data
984 - input_section->vma);
986 return true;
989 /* Perform a relocation as part of a final link. */
991 static bfd_reloc_status_type
992 elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
993 input_section, contents, rel, value,
994 info, sym_sec, sym_name, sym_flags, h)
995 reloc_howto_type * howto;
996 bfd * input_bfd;
997 bfd * output_bfd;
998 asection * input_section;
999 bfd_byte * contents;
1000 Elf_Internal_Rela * rel;
1001 bfd_vma value;
1002 struct bfd_link_info * info;
1003 asection * sym_sec;
1004 const char * sym_name;
1005 unsigned char sym_flags;
1006 struct elf_link_hash_entry * h;
1008 unsigned long r_type = howto->type;
1009 unsigned long r_symndx;
1010 bfd_byte * hit_data = contents + rel->r_offset;
1011 bfd * dynobj = NULL;
1012 Elf_Internal_Shdr * symtab_hdr;
1013 struct elf_link_hash_entry ** sym_hashes;
1014 bfd_vma * local_got_offsets;
1015 asection * sgot = NULL;
1016 asection * splt = NULL;
1017 asection * sreloc = NULL;
1018 bfd_vma addend;
1019 bfd_signed_vma signed_addend;
1020 struct elf32_arm_link_hash_table * globals;
1022 /* If the start address has been set, then set the EF_ARM_HASENTRY
1023 flag. Setting this more than once is redundant, but the cost is
1024 not too high, and it keeps the code simple.
1026 The test is done here, rather than somewhere else, because the
1027 start address is only set just before the final link commences.
1029 Note - if the user deliberately sets a start address of 0, the
1030 flag will not be set. */
1031 if (bfd_get_start_address (output_bfd) != 0)
1032 elf_elfheader (output_bfd)->e_flags |= EF_ARM_HASENTRY;
1034 globals = elf32_arm_hash_table (info);
1036 dynobj = elf_hash_table (info)->dynobj;
1037 if (dynobj)
1039 sgot = bfd_get_section_by_name (dynobj, ".got");
1040 splt = bfd_get_section_by_name (dynobj, ".plt");
1042 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1043 sym_hashes = elf_sym_hashes (input_bfd);
1044 local_got_offsets = elf_local_got_offsets (input_bfd);
1045 r_symndx = ELF32_R_SYM (rel->r_info);
1047 #ifdef USE_REL
1048 addend = bfd_get_32 (input_bfd, hit_data) & howto->src_mask;
1050 if (addend & ((howto->src_mask + 1) >> 1))
1052 signed_addend = -1;
1053 signed_addend &= ~ howto->src_mask;
1054 signed_addend |= addend;
1056 else
1057 signed_addend = addend;
1058 #else
1059 addend = signed_addend = rel->r_addend;
1060 #endif
1062 switch (r_type)
1064 case R_ARM_NONE:
1065 return bfd_reloc_ok;
1067 case R_ARM_PC24:
1068 case R_ARM_ABS32:
1069 case R_ARM_REL32:
1070 #ifndef OLD_ARM_ABI
1071 case R_ARM_XPC25:
1072 #endif
1073 /* When generating a shared object, these relocations are copied
1074 into the output file to be resolved at run time. */
1075 if (info->shared
1076 && (r_type != R_ARM_PC24
1077 || (h != NULL
1078 && h->dynindx != -1
1079 && (! info->symbolic
1080 || (h->elf_link_hash_flags
1081 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1083 Elf_Internal_Rel outrel;
1084 boolean skip, relocate;
1086 if (sreloc == NULL)
1088 const char * name;
1090 name = (bfd_elf_string_from_elf_section
1091 (input_bfd,
1092 elf_elfheader (input_bfd)->e_shstrndx,
1093 elf_section_data (input_section)->rel_hdr.sh_name));
1094 if (name == NULL)
1095 return bfd_reloc_notsupported;
1097 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
1098 && strcmp (bfd_get_section_name (input_bfd,
1099 input_section),
1100 name + 4) == 0);
1102 sreloc = bfd_get_section_by_name (dynobj, name);
1103 BFD_ASSERT (sreloc != NULL);
1106 skip = false;
1108 if (elf_section_data (input_section)->stab_info == NULL)
1109 outrel.r_offset = rel->r_offset;
1110 else
1112 bfd_vma off;
1114 off = (_bfd_stab_section_offset
1115 (output_bfd, &elf_hash_table (info)->stab_info,
1116 input_section,
1117 & elf_section_data (input_section)->stab_info,
1118 rel->r_offset));
1119 if (off == (bfd_vma) -1)
1120 skip = true;
1121 outrel.r_offset = off;
1124 outrel.r_offset += (input_section->output_section->vma
1125 + input_section->output_offset);
1127 if (skip)
1129 memset (&outrel, 0, sizeof outrel);
1130 relocate = false;
1132 else if (r_type == R_ARM_PC24)
1134 BFD_ASSERT (h != NULL && h->dynindx != -1);
1135 if ((input_section->flags & SEC_ALLOC) != 0)
1136 relocate = false;
1137 else
1138 relocate = true;
1139 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_PC24);
1141 else
1143 if (h == NULL
1144 || ((info->symbolic || h->dynindx == -1)
1145 && (h->elf_link_hash_flags
1146 & ELF_LINK_HASH_DEF_REGULAR) != 0))
1148 relocate = true;
1149 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1151 else
1153 BFD_ASSERT (h->dynindx != -1);
1154 if ((input_section->flags & SEC_ALLOC) != 0)
1155 relocate = false;
1156 else
1157 relocate = true;
1158 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_ABS32);
1162 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1163 (((Elf32_External_Rel *)
1164 sreloc->contents)
1165 + sreloc->reloc_count));
1166 ++sreloc->reloc_count;
1168 /* If this reloc is against an external symbol, we do not want to
1169 fiddle with the addend. Otherwise, we need to include the symbol
1170 value so that it becomes an addend for the dynamic reloc. */
1171 if (! relocate)
1172 return bfd_reloc_ok;
1174 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1175 contents, rel->r_offset, value,
1176 (bfd_vma) 0);
1178 else switch (r_type)
1180 #ifndef OLD_ARM_ABI
1181 case R_ARM_XPC25: /* Arm BLX instruction. */
1182 #endif
1183 case R_ARM_PC24: /* Arm B/BL instruction */
1184 #ifndef OLD_ARM_ABI
1185 if (r_type == R_ARM_XPC25)
1187 /* Check for Arm calling Arm function. */
1188 /* FIXME: Should we translate the instruction into a BL
1189 instruction instead ? */
1190 if (sym_flags != STT_ARM_TFUNC)
1191 _bfd_error_handler (_("\
1192 %s: Warning: Arm BLX instruction targets Arm function '%s'."),
1193 bfd_get_filename (input_bfd),
1194 h ? h->root.root.string : "(local)");
1196 else
1197 #endif
1199 /* Check for Arm calling Thumb function. */
1200 if (sym_flags == STT_ARM_TFUNC)
1202 elf32_arm_to_thumb_stub (info, sym_name, input_bfd, output_bfd,
1203 input_section, hit_data, sym_sec, rel->r_offset,
1204 signed_addend, value);
1205 return bfd_reloc_ok;
1209 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1210 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0)
1212 /* The old way of doing things. Trearing the addend as a
1213 byte sized field and adding in the pipeline offset. */
1214 value -= (input_section->output_section->vma
1215 + input_section->output_offset);
1216 value -= rel->r_offset;
1217 value += addend;
1219 if (! globals->no_pipeline_knowledge)
1220 value -= 8;
1222 else
1224 /* The ARM ELF ABI says that this reloc is computed as: S - P + A
1225 where:
1226 S is the address of the symbol in the relocation.
1227 P is address of the instruction being relocated.
1228 A is the addend (extracted from the instruction) in bytes.
1230 S is held in 'value'.
1231 P is the base address of the section containing the instruction
1232 plus the offset of the reloc into that section, ie:
1233 (input_section->output_section->vma +
1234 input_section->output_offset +
1235 rel->r_offset).
1236 A is the addend, converted into bytes, ie:
1237 (signed_addend * 4)
1239 Note: None of these operations have knowledge of the pipeline
1240 size of the processor, thus it is up to the assembler to encode
1241 this information into the addend. */
1242 value -= (input_section->output_section->vma
1243 + input_section->output_offset);
1244 value -= rel->r_offset;
1245 value += (signed_addend << howto->size);
1247 /* Previous versions of this code also used to add in the pipeline
1248 offset here. This is wrong because the linker is not supposed
1249 to know about such things, and one day it might change. In order
1250 to support old binaries that need the old behaviour however, so
1251 we attempt to detect which ABI was used to create the reloc. */
1252 if (! globals->no_pipeline_knowledge)
1254 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
1256 i_ehdrp = elf_elfheader (input_bfd);
1258 if (i_ehdrp->e_ident[EI_OSABI] == 0)
1259 value -= 8;
1263 signed_addend = value;
1264 signed_addend >>= howto->rightshift;
1266 /* It is not an error for an undefined weak reference to be
1267 out of range. Any program that branches to such a symbol
1268 is going to crash anyway, so there is no point worrying
1269 about getting the destination exactly right. */
1270 if (! h || h->root.type != bfd_link_hash_undefweak)
1272 /* Perform a signed range check. */
1273 if ( signed_addend > ((bfd_signed_vma) (howto->dst_mask >> 1))
1274 || signed_addend < - ((bfd_signed_vma) ((howto->dst_mask + 1) >> 1)))
1275 return bfd_reloc_overflow;
1278 #ifndef OLD_ARM_ABI
1279 /* If necessary set the H bit in the BLX instruction. */
1280 if (r_type == R_ARM_XPC25 && ((value & 2) == 2))
1281 value = (signed_addend & howto->dst_mask)
1282 | (bfd_get_32 (input_bfd, hit_data) & (~ howto->dst_mask))
1283 | (1 << 24);
1284 else
1285 #endif
1286 value = (signed_addend & howto->dst_mask)
1287 | (bfd_get_32 (input_bfd, hit_data) & (~ howto->dst_mask));
1288 break;
1290 case R_ARM_ABS32:
1291 value += addend;
1292 if (sym_flags == STT_ARM_TFUNC)
1293 value |= 1;
1294 break;
1296 case R_ARM_REL32:
1297 value -= (input_section->output_section->vma
1298 + input_section->output_offset);
1299 value += addend;
1300 break;
1303 bfd_put_32 (input_bfd, value, hit_data);
1304 return bfd_reloc_ok;
1306 case R_ARM_ABS8:
1307 value += addend;
1308 if ((long) value > 0x7f || (long) value < -0x80)
1309 return bfd_reloc_overflow;
1311 bfd_put_8 (input_bfd, value, hit_data);
1312 return bfd_reloc_ok;
1314 case R_ARM_ABS16:
1315 value += addend;
1317 if ((long) value > 0x7fff || (long) value < -0x8000)
1318 return bfd_reloc_overflow;
1320 bfd_put_16 (input_bfd, value, hit_data);
1321 return bfd_reloc_ok;
1323 case R_ARM_ABS12:
1324 /* Support ldr and str instruction for the arm */
1325 /* Also thumb b (unconditional branch). ??? Really? */
1326 value += addend;
1328 if ((long) value > 0x7ff || (long) value < -0x800)
1329 return bfd_reloc_overflow;
1331 value |= (bfd_get_32 (input_bfd, hit_data) & 0xfffff000);
1332 bfd_put_32 (input_bfd, value, hit_data);
1333 return bfd_reloc_ok;
1335 case R_ARM_THM_ABS5:
1336 /* Support ldr and str instructions for the thumb. */
1337 #ifdef USE_REL
1338 /* Need to refetch addend. */
1339 addend = bfd_get_16 (input_bfd, hit_data) & howto->src_mask;
1340 /* ??? Need to determine shift amount from operand size. */
1341 addend >>= howto->rightshift;
1342 #endif
1343 value += addend;
1345 /* ??? Isn't value unsigned? */
1346 if ((long) value > 0x1f || (long) value < -0x10)
1347 return bfd_reloc_overflow;
1349 /* ??? Value needs to be properly shifted into place first. */
1350 value |= bfd_get_16 (input_bfd, hit_data) & 0xf83f;
1351 bfd_put_16 (input_bfd, value, hit_data);
1352 return bfd_reloc_ok;
1354 #ifndef OLD_ARM_ABI
1355 case R_ARM_THM_XPC22:
1356 #endif
1357 case R_ARM_THM_PC22:
1358 /* Thumb BL (branch long instruction). */
1360 bfd_vma relocation;
1361 boolean overflow = false;
1362 bfd_vma upper_insn = bfd_get_16 (input_bfd, hit_data);
1363 bfd_vma lower_insn = bfd_get_16 (input_bfd, hit_data + 2);
1364 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
1365 bfd_signed_vma reloc_signed_min = ~ reloc_signed_max;
1366 bfd_vma check;
1367 bfd_signed_vma signed_check;
1369 #ifdef USE_REL
1370 /* Need to refetch the addend and squish the two 11 bit pieces
1371 together. */
1373 bfd_vma upper = upper_insn & 0x7ff;
1374 bfd_vma lower = lower_insn & 0x7ff;
1375 upper = (upper ^ 0x400) - 0x400; /* Sign extend. */
1376 addend = (upper << 12) | (lower << 1);
1377 signed_addend = addend;
1379 #endif
1380 #ifndef OLD_ARM_ABI
1381 if (r_type == R_ARM_THM_XPC22)
1383 /* Check for Thumb to Thumb call. */
1384 /* FIXME: Should we translate the instruction into a BL
1385 instruction instead ? */
1386 if (sym_flags == STT_ARM_TFUNC)
1387 _bfd_error_handler (_("\
1388 %s: Warning: Thumb BLX instruction targets thumb function '%s'."),
1389 bfd_get_filename (input_bfd),
1390 h ? h->root.root.string : "(local)");
1392 else
1393 #endif
1395 /* If it is not a call to Thumb, assume call to Arm.
1396 If it is a call relative to a section name, then it is not a
1397 function call at all, but rather a long jump. */
1398 if (sym_flags != STT_ARM_TFUNC && sym_flags != STT_SECTION)
1400 if (elf32_thumb_to_arm_stub
1401 (info, sym_name, input_bfd, output_bfd, input_section,
1402 hit_data, sym_sec, rel->r_offset, signed_addend, value))
1403 return bfd_reloc_ok;
1404 else
1405 return bfd_reloc_dangerous;
1409 relocation = value + signed_addend;
1411 relocation -= (input_section->output_section->vma
1412 + input_section->output_offset
1413 + rel->r_offset);
1415 if (! globals->no_pipeline_knowledge)
1417 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form. */
1419 i_ehdrp = elf_elfheader (input_bfd);
1421 /* Previous versions of this code also used to add in the pipline
1422 offset here. This is wrong because the linker is not supposed
1423 to know about such things, and one day it might change. In order
1424 to support old binaries that need the old behaviour however, so
1425 we attempt to detect which ABI was used to create the reloc. */
1426 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1427 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0
1428 || i_ehdrp->e_ident[EI_OSABI] == 0)
1429 relocation += 4;
1432 check = relocation >> howto->rightshift;
1434 /* If this is a signed value, the rightshift just dropped
1435 leading 1 bits (assuming twos complement). */
1436 if ((bfd_signed_vma) relocation >= 0)
1437 signed_check = check;
1438 else
1439 signed_check = check | ~((bfd_vma) -1 >> howto->rightshift);
1441 /* Assumes two's complement. */
1442 if (signed_check > reloc_signed_max || signed_check < reloc_signed_min)
1443 overflow = true;
1445 /* Put RELOCATION back into the insn. */
1446 upper_insn = (upper_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 12) & 0x7ff);
1447 lower_insn = (lower_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 1) & 0x7ff);
1449 #ifndef OLD_ARM_ABI
1450 if (r_type == R_ARM_THM_XPC22
1451 && ((lower_insn & 0x1800) == 0x0800))
1452 /* Remove bit zero of the adjusted offset. Bit zero can only be
1453 set if the upper insn is at a half-word boundary, since the
1454 destination address, an ARM instruction, must always be on a
1455 word boundary. The semantics of the BLX (1) instruction, however,
1456 are that bit zero in the offset must always be zero, and the
1457 corresponding bit one in the target address will be set from bit
1458 one of the source address. */
1459 lower_insn &= ~1;
1460 #endif
1461 /* Put the relocated value back in the object file: */
1462 bfd_put_16 (input_bfd, upper_insn, hit_data);
1463 bfd_put_16 (input_bfd, lower_insn, hit_data + 2);
1465 return (overflow ? bfd_reloc_overflow : bfd_reloc_ok);
1467 break;
1469 case R_ARM_GNU_VTINHERIT:
1470 case R_ARM_GNU_VTENTRY:
1471 return bfd_reloc_ok;
1473 case R_ARM_COPY:
1474 return bfd_reloc_notsupported;
1476 case R_ARM_GLOB_DAT:
1477 return bfd_reloc_notsupported;
1479 case R_ARM_JUMP_SLOT:
1480 return bfd_reloc_notsupported;
1482 case R_ARM_RELATIVE:
1483 return bfd_reloc_notsupported;
1485 case R_ARM_GOTOFF:
1486 /* Relocation is relative to the start of the
1487 global offset table. */
1489 BFD_ASSERT (sgot != NULL);
1490 if (sgot == NULL)
1491 return bfd_reloc_notsupported;
1493 /* Note that sgot->output_offset is not involved in this
1494 calculation. We always want the start of .got. If we
1495 define _GLOBAL_OFFSET_TABLE in a different way, as is
1496 permitted by the ABI, we might have to change this
1497 calculation. */
1498 value -= sgot->output_section->vma;
1499 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1500 contents, rel->r_offset, value,
1501 (bfd_vma) 0);
1503 case R_ARM_GOTPC:
1504 /* Use global offset table as symbol value. */
1505 BFD_ASSERT (sgot != NULL);
1507 if (sgot == NULL)
1508 return bfd_reloc_notsupported;
1510 value = sgot->output_section->vma;
1511 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1512 contents, rel->r_offset, value,
1513 (bfd_vma) 0);
1515 case R_ARM_GOT32:
1516 /* Relocation is to the entry for this symbol in the
1517 global offset table. */
1518 if (sgot == NULL)
1519 return bfd_reloc_notsupported;
1521 if (h != NULL)
1523 bfd_vma off;
1525 off = h->got.offset;
1526 BFD_ASSERT (off != (bfd_vma) -1);
1528 if (!elf_hash_table (info)->dynamic_sections_created ||
1529 (info->shared && (info->symbolic || h->dynindx == -1)
1530 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1532 /* This is actually a static link, or it is a -Bsymbolic link
1533 and the symbol is defined locally. We must initialize this
1534 entry in the global offset table. Since the offset must
1535 always be a multiple of 4, we use the least significant bit
1536 to record whether we have initialized it already.
1538 When doing a dynamic link, we create a .rel.got relocation
1539 entry to initialize the value. This is done in the
1540 finish_dynamic_symbol routine. */
1541 if ((off & 1) != 0)
1542 off &= ~1;
1543 else
1545 bfd_put_32 (output_bfd, value, sgot->contents + off);
1546 h->got.offset |= 1;
1550 value = sgot->output_offset + off;
1552 else
1554 bfd_vma off;
1556 BFD_ASSERT (local_got_offsets != NULL &&
1557 local_got_offsets[r_symndx] != (bfd_vma) -1);
1559 off = local_got_offsets[r_symndx];
1561 /* The offset must always be a multiple of 4. We use the
1562 least significant bit to record whether we have already
1563 generated the necessary reloc. */
1564 if ((off & 1) != 0)
1565 off &= ~1;
1566 else
1568 bfd_put_32 (output_bfd, value, sgot->contents + off);
1570 if (info->shared)
1572 asection * srelgot;
1573 Elf_Internal_Rel outrel;
1575 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
1576 BFD_ASSERT (srelgot != NULL);
1578 outrel.r_offset = (sgot->output_section->vma
1579 + sgot->output_offset
1580 + off);
1581 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1582 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1583 (((Elf32_External_Rel *)
1584 srelgot->contents)
1585 + srelgot->reloc_count));
1586 ++srelgot->reloc_count;
1589 local_got_offsets[r_symndx] |= 1;
1592 value = sgot->output_offset + off;
1595 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1596 contents, rel->r_offset, value,
1597 (bfd_vma) 0);
1599 case R_ARM_PLT32:
1600 /* Relocation is to the entry for this symbol in the
1601 procedure linkage table. */
1603 /* Resolve a PLT32 reloc against a local symbol directly,
1604 without using the procedure linkage table. */
1605 if (h == NULL)
1606 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1607 contents, rel->r_offset, value,
1608 (bfd_vma) 0);
1610 if (h->plt.offset == (bfd_vma) -1)
1611 /* We didn't make a PLT entry for this symbol. This
1612 happens when statically linking PIC code, or when
1613 using -Bsymbolic. */
1614 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1615 contents, rel->r_offset, value,
1616 (bfd_vma) 0);
1618 BFD_ASSERT(splt != NULL);
1619 if (splt == NULL)
1620 return bfd_reloc_notsupported;
1622 value = (splt->output_section->vma
1623 + splt->output_offset
1624 + h->plt.offset);
1625 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1626 contents, rel->r_offset, value,
1627 (bfd_vma) 0);
1629 case R_ARM_SBREL32:
1630 return bfd_reloc_notsupported;
1632 case R_ARM_AMP_VCALL9:
1633 return bfd_reloc_notsupported;
1635 case R_ARM_RSBREL32:
1636 return bfd_reloc_notsupported;
1638 case R_ARM_THM_RPC22:
1639 return bfd_reloc_notsupported;
1641 case R_ARM_RREL32:
1642 return bfd_reloc_notsupported;
1644 case R_ARM_RABS32:
1645 return bfd_reloc_notsupported;
1647 case R_ARM_RPC24:
1648 return bfd_reloc_notsupported;
1650 case R_ARM_RBASE:
1651 return bfd_reloc_notsupported;
1653 default:
1654 return bfd_reloc_notsupported;
1658 #ifdef USE_REL
1659 /* Add INCREMENT to the reloc (of type HOWTO) at ADDRESS. */
1660 static void
1661 arm_add_to_rel (abfd, address, howto, increment)
1662 bfd * abfd;
1663 bfd_byte * address;
1664 reloc_howto_type * howto;
1665 bfd_signed_vma increment;
1667 bfd_signed_vma addend;
1669 if (howto->type == R_ARM_THM_PC22)
1671 int upper_insn, lower_insn;
1672 int upper, lower;
1674 upper_insn = bfd_get_16 (abfd, address);
1675 lower_insn = bfd_get_16 (abfd, address + 2);
1676 upper = upper_insn & 0x7ff;
1677 lower = lower_insn & 0x7ff;
1679 addend = (upper << 12) | (lower << 1);
1680 addend += increment;
1681 addend >>= 1;
1683 upper_insn = (upper_insn & 0xf800) | ((addend >> 11) & 0x7ff);
1684 lower_insn = (lower_insn & 0xf800) | (addend & 0x7ff);
1686 bfd_put_16 (abfd, upper_insn, address);
1687 bfd_put_16 (abfd, lower_insn, address + 2);
1689 else
1691 bfd_vma contents;
1693 contents = bfd_get_32 (abfd, address);
1695 /* Get the (signed) value from the instruction. */
1696 addend = contents & howto->src_mask;
1697 if (addend & ((howto->src_mask + 1) >> 1))
1699 bfd_signed_vma mask;
1701 mask = -1;
1702 mask &= ~ howto->src_mask;
1703 addend |= mask;
1706 /* Add in the increment, (which is a byte value). */
1707 switch (howto->type)
1709 default:
1710 addend += increment;
1711 break;
1713 case R_ARM_PC24:
1714 addend <<= howto->size;
1715 addend += increment;
1717 /* Should we check for overflow here ? */
1719 /* Drop any undesired bits. */
1720 addend >>= howto->rightshift;
1721 break;
1724 contents = (contents & ~ howto->dst_mask) | (addend & howto->dst_mask);
1726 bfd_put_32 (abfd, contents, address);
1729 #endif /* USE_REL */
1731 /* Relocate an ARM ELF section. */
1732 static boolean
1733 elf32_arm_relocate_section (output_bfd, info, input_bfd, input_section,
1734 contents, relocs, local_syms, local_sections)
1735 bfd * output_bfd;
1736 struct bfd_link_info * info;
1737 bfd * input_bfd;
1738 asection * input_section;
1739 bfd_byte * contents;
1740 Elf_Internal_Rela * relocs;
1741 Elf_Internal_Sym * local_syms;
1742 asection ** local_sections;
1744 Elf_Internal_Shdr * symtab_hdr;
1745 struct elf_link_hash_entry ** sym_hashes;
1746 Elf_Internal_Rela * rel;
1747 Elf_Internal_Rela * relend;
1748 const char * name;
1750 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1751 sym_hashes = elf_sym_hashes (input_bfd);
1753 rel = relocs;
1754 relend = relocs + input_section->reloc_count;
1755 for (; rel < relend; rel++)
1757 int r_type;
1758 reloc_howto_type * howto;
1759 unsigned long r_symndx;
1760 Elf_Internal_Sym * sym;
1761 asection * sec;
1762 struct elf_link_hash_entry * h;
1763 bfd_vma relocation;
1764 bfd_reloc_status_type r;
1765 arelent bfd_reloc;
1767 r_symndx = ELF32_R_SYM (rel->r_info);
1768 r_type = ELF32_R_TYPE (rel->r_info);
1770 if ( r_type == R_ARM_GNU_VTENTRY
1771 || r_type == R_ARM_GNU_VTINHERIT)
1772 continue;
1774 elf32_arm_info_to_howto (input_bfd, & bfd_reloc, rel);
1775 howto = bfd_reloc.howto;
1777 if (info->relocateable)
1779 /* This is a relocateable link. We don't have to change
1780 anything, unless the reloc is against a section symbol,
1781 in which case we have to adjust according to where the
1782 section symbol winds up in the output section. */
1783 if (r_symndx < symtab_hdr->sh_info)
1785 sym = local_syms + r_symndx;
1786 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1788 sec = local_sections[r_symndx];
1789 #ifdef USE_REL
1790 arm_add_to_rel (input_bfd, contents + rel->r_offset,
1791 howto, sec->output_offset + sym->st_value);
1792 #else
1793 rel->r_addend += (sec->output_offset + sym->st_value)
1794 >> howto->rightshift;
1795 #endif
1799 continue;
1802 /* This is a final link. */
1803 h = NULL;
1804 sym = NULL;
1805 sec = NULL;
1807 if (r_symndx < symtab_hdr->sh_info)
1809 sym = local_syms + r_symndx;
1810 sec = local_sections[r_symndx];
1811 relocation = (sec->output_section->vma
1812 + sec->output_offset
1813 + sym->st_value);
1815 else
1817 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1819 while ( h->root.type == bfd_link_hash_indirect
1820 || h->root.type == bfd_link_hash_warning)
1821 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1823 if ( h->root.type == bfd_link_hash_defined
1824 || h->root.type == bfd_link_hash_defweak)
1826 int relocation_needed = 1;
1828 sec = h->root.u.def.section;
1830 /* In these cases, we don't need the relocation value.
1831 We check specially because in some obscure cases
1832 sec->output_section will be NULL. */
1833 switch (r_type)
1835 case R_ARM_PC24:
1836 case R_ARM_ABS32:
1837 if (info->shared
1838 && (
1839 (!info->symbolic && h->dynindx != -1)
1840 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1842 && ((input_section->flags & SEC_ALLOC) != 0
1843 /* DWARF will emit R_ARM_ABS32 relocations in its
1844 sections against symbols defined externally
1845 in shared libraries. We can't do anything
1846 with them here. */
1847 || ((input_section->flags & SEC_DEBUGGING) != 0
1848 && (h->elf_link_hash_flags
1849 & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
1851 relocation_needed = 0;
1852 break;
1854 case R_ARM_GOTPC:
1855 relocation_needed = 0;
1856 break;
1858 case R_ARM_GOT32:
1859 if (elf_hash_table(info)->dynamic_sections_created
1860 && (!info->shared
1861 || (!info->symbolic && h->dynindx != -1)
1862 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1865 relocation_needed = 0;
1866 break;
1868 case R_ARM_PLT32:
1869 if (h->plt.offset != (bfd_vma)-1)
1870 relocation_needed = 0;
1871 break;
1873 default:
1874 if (sec->output_section == NULL)
1876 (*_bfd_error_handler)
1877 (_("%s: warning: unresolvable relocation against symbol `%s' from %s section"),
1878 bfd_get_filename (input_bfd), h->root.root.string,
1879 bfd_get_section_name (input_bfd, input_section));
1880 relocation_needed = 0;
1884 if (relocation_needed)
1885 relocation = h->root.u.def.value
1886 + sec->output_section->vma
1887 + sec->output_offset;
1888 else
1889 relocation = 0;
1891 else if (h->root.type == bfd_link_hash_undefweak)
1892 relocation = 0;
1893 else if (info->shared && !info->symbolic
1894 && !info->no_undefined
1895 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1896 relocation = 0;
1897 else
1899 if (!((*info->callbacks->undefined_symbol)
1900 (info, h->root.root.string, input_bfd,
1901 input_section, rel->r_offset,
1902 (!info->shared || info->no_undefined
1903 || ELF_ST_VISIBILITY (h->other)))))
1904 return false;
1905 relocation = 0;
1909 if (h != NULL)
1910 name = h->root.root.string;
1911 else
1913 name = (bfd_elf_string_from_elf_section
1914 (input_bfd, symtab_hdr->sh_link, sym->st_name));
1915 if (name == NULL || *name == '\0')
1916 name = bfd_section_name (input_bfd, sec);
1919 r = elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
1920 input_section, contents, rel,
1921 relocation, info, sec, name,
1922 (h ? ELF_ST_TYPE (h->type) :
1923 ELF_ST_TYPE (sym->st_info)), h);
1925 if (r != bfd_reloc_ok)
1927 const char * msg = (const char *) 0;
1929 switch (r)
1931 case bfd_reloc_overflow:
1932 /* If the overflowing reloc was to an undefined symbol,
1933 we have already printed one error message and there
1934 is no point complaining again. */
1935 if ((! h ||
1936 h->root.type != bfd_link_hash_undefined)
1937 && (!((*info->callbacks->reloc_overflow)
1938 (info, name, howto->name, (bfd_vma) 0,
1939 input_bfd, input_section, rel->r_offset))))
1940 return false;
1941 break;
1943 case bfd_reloc_undefined:
1944 if (!((*info->callbacks->undefined_symbol)
1945 (info, name, input_bfd, input_section,
1946 rel->r_offset, true)))
1947 return false;
1948 break;
1950 case bfd_reloc_outofrange:
1951 msg = _("internal error: out of range error");
1952 goto common_error;
1954 case bfd_reloc_notsupported:
1955 msg = _("internal error: unsupported relocation error");
1956 goto common_error;
1958 case bfd_reloc_dangerous:
1959 msg = _("internal error: dangerous error");
1960 goto common_error;
1962 default:
1963 msg = _("internal error: unknown error");
1964 /* fall through */
1966 common_error:
1967 if (!((*info->callbacks->warning)
1968 (info, msg, name, input_bfd, input_section,
1969 rel->r_offset)))
1970 return false;
1971 break;
1976 return true;
1979 /* Function to keep ARM specific flags in the ELF header. */
1980 static boolean
1981 elf32_arm_set_private_flags (abfd, flags)
1982 bfd *abfd;
1983 flagword flags;
1985 if (elf_flags_init (abfd)
1986 && elf_elfheader (abfd)->e_flags != flags)
1988 if (EF_ARM_EABI_VERSION (flags) == EF_ARM_EABI_UNKNOWN)
1990 if (flags & EF_ARM_INTERWORK)
1991 _bfd_error_handler (_("\
1992 Warning: Not setting interwork flag of %s since it has already been specified as non-interworking"),
1993 bfd_get_filename (abfd));
1994 else
1995 _bfd_error_handler (_("\
1996 Warning: Clearing the interwork flag of %s due to outside request"),
1997 bfd_get_filename (abfd));
2000 else
2002 elf_elfheader (abfd)->e_flags = flags;
2003 elf_flags_init (abfd) = true;
2006 return true;
2009 /* Copy backend specific data from one object module to another. */
2011 static boolean
2012 elf32_arm_copy_private_bfd_data (ibfd, obfd)
2013 bfd *ibfd;
2014 bfd *obfd;
2016 flagword in_flags;
2017 flagword out_flags;
2019 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
2020 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
2021 return true;
2023 in_flags = elf_elfheader (ibfd)->e_flags;
2024 out_flags = elf_elfheader (obfd)->e_flags;
2026 if (elf_flags_init (obfd)
2027 && EF_ARM_EABI_VERSION (out_flags) == EF_ARM_EABI_UNKNOWN
2028 && in_flags != out_flags)
2030 /* Cannot mix APCS26 and APCS32 code. */
2031 if ((in_flags & EF_ARM_APCS_26) != (out_flags & EF_ARM_APCS_26))
2032 return false;
2034 /* Cannot mix float APCS and non-float APCS code. */
2035 if ((in_flags & EF_ARM_APCS_FLOAT) != (out_flags & EF_ARM_APCS_FLOAT))
2036 return false;
2038 /* If the src and dest have different interworking flags
2039 then turn off the interworking bit. */
2040 if ((in_flags & EF_ARM_INTERWORK) != (out_flags & EF_ARM_INTERWORK))
2042 if (out_flags & EF_ARM_INTERWORK)
2043 _bfd_error_handler (_("\
2044 Warning: Clearing the interwork flag in %s because non-interworking code in %s has been linked with it"),
2045 bfd_get_filename (obfd), bfd_get_filename (ibfd));
2047 in_flags &= ~EF_ARM_INTERWORK;
2050 /* Likewise for PIC, though don't warn for this case. */
2051 if ((in_flags & EF_ARM_PIC) != (out_flags & EF_ARM_PIC))
2052 in_flags &= ~EF_ARM_PIC;
2055 elf_elfheader (obfd)->e_flags = in_flags;
2056 elf_flags_init (obfd) = true;
2058 return true;
2061 /* Merge backend specific data from an object file to the output
2062 object file when linking. */
2064 static boolean
2065 elf32_arm_merge_private_bfd_data (ibfd, obfd)
2066 bfd * ibfd;
2067 bfd * obfd;
2069 flagword out_flags;
2070 flagword in_flags;
2071 boolean flags_compatible = true;
2072 boolean null_input_bfd = true;
2073 asection *sec;
2075 /* Check if we have the same endianess. */
2076 if (_bfd_generic_verify_endian_match (ibfd, obfd) == false)
2077 return false;
2079 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
2080 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
2081 return true;
2083 /* The input BFD must have had its flags initialised. */
2084 /* The following seems bogus to me -- The flags are initialized in
2085 the assembler but I don't think an elf_flags_init field is
2086 written into the object. */
2087 /* BFD_ASSERT (elf_flags_init (ibfd)); */
2089 in_flags = elf_elfheader (ibfd)->e_flags;
2090 out_flags = elf_elfheader (obfd)->e_flags;
2092 if (!elf_flags_init (obfd))
2094 /* If the input is the default architecture and had the default
2095 flags then do not bother setting the flags for the output
2096 architecture, instead allow future merges to do this. If no
2097 future merges ever set these flags then they will retain their
2098 uninitialised values, which surprise surprise, correspond
2099 to the default values. */
2100 if (bfd_get_arch_info (ibfd)->the_default
2101 && elf_elfheader (ibfd)->e_flags == 0)
2102 return true;
2104 elf_flags_init (obfd) = true;
2105 elf_elfheader (obfd)->e_flags = in_flags;
2107 if (bfd_get_arch (obfd) == bfd_get_arch (ibfd)
2108 && bfd_get_arch_info (obfd)->the_default)
2109 return bfd_set_arch_mach (obfd, bfd_get_arch (ibfd), bfd_get_mach (ibfd));
2111 return true;
2114 /* Identical flags must be compatible. */
2115 if (in_flags == out_flags)
2116 return true;
2118 /* Check to see if the input BFD actually contains any sections.
2119 If not, its flags may not have been initialised either, but it cannot
2120 actually cause any incompatibility. */
2121 for (sec = ibfd->sections; sec != NULL; sec = sec->next)
2123 /* Ignore synthetic glue sections. */
2124 if (strcmp (sec->name, ".glue_7")
2125 && strcmp (sec->name, ".glue_7t"))
2127 null_input_bfd = false;
2128 break;
2131 if (null_input_bfd)
2132 return true;
2134 /* Complain about various flag mismatches. */
2135 if (EF_ARM_EABI_VERSION (in_flags) != EF_ARM_EABI_VERSION (out_flags))
2137 _bfd_error_handler (_("\
2138 Error: %s compiled for EABI version %d, whereas %s is compiled for version %d"),
2139 bfd_get_filename (ibfd),
2140 (in_flags & EF_ARM_EABIMASK) >> 24,
2141 bfd_get_filename (obfd),
2142 (out_flags & EF_ARM_EABIMASK) >> 24);
2143 return false;
2146 /* Not sure what needs to be checked for EABI versions >= 1. */
2147 if (EF_ARM_EABI_VERSION (in_flags) == EF_ARM_EABI_UNKNOWN)
2149 if ((in_flags & EF_ARM_APCS_26) != (out_flags & EF_ARM_APCS_26))
2151 _bfd_error_handler (_("\
2152 Error: %s compiled for APCS-%d, whereas %s is compiled for APCS-%d"),
2153 bfd_get_filename (ibfd),
2154 in_flags & EF_ARM_APCS_26 ? 26 : 32,
2155 bfd_get_filename (obfd),
2156 out_flags & EF_ARM_APCS_26 ? 26 : 32);
2157 flags_compatible = false;
2160 if ((in_flags & EF_ARM_APCS_FLOAT) != (out_flags & EF_ARM_APCS_FLOAT))
2162 _bfd_error_handler (_("\
2163 Error: %s passes floats in %s registers, whereas %s passes them in %s registers"),
2164 bfd_get_filename (ibfd),
2165 in_flags & EF_ARM_APCS_FLOAT ? _("float") : _("integer"),
2166 bfd_get_filename (obfd),
2167 out_flags & EF_ARM_APCS_26 ? _("float") : _("integer"));
2168 flags_compatible = false;
2171 #ifdef EF_ARM_SOFT_FLOAT
2172 if ((in_flags & EF_ARM_SOFT_FLOAT) != (out_flags & EF_ARM_SOFT_FLOAT))
2174 _bfd_error_handler (_ ("\
2175 Error: %s uses %s floating point, whereas %s uses %s floating point"),
2176 bfd_get_filename (ibfd),
2177 in_flags & EF_ARM_SOFT_FLOAT ? _("soft") : _("hard"),
2178 bfd_get_filename (obfd),
2179 out_flags & EF_ARM_SOFT_FLOAT ? _("soft") : _("hard"));
2180 flags_compatible = false;
2182 #endif
2184 /* Interworking mismatch is only a warning. */
2185 if ((in_flags & EF_ARM_INTERWORK) != (out_flags & EF_ARM_INTERWORK))
2186 _bfd_error_handler (_("\
2187 Warning: %s %s interworking, whereas %s %s"),
2188 bfd_get_filename (ibfd),
2189 in_flags & EF_ARM_INTERWORK ? _("supports") : _("does not support"),
2190 bfd_get_filename (obfd),
2191 out_flags & EF_ARM_INTERWORK ? _("does") : _("does not"));
2194 return flags_compatible;
2197 /* Display the flags field. */
2199 static boolean
2200 elf32_arm_print_private_bfd_data (abfd, ptr)
2201 bfd *abfd;
2202 PTR ptr;
2204 FILE * file = (FILE *) ptr;
2205 unsigned long flags;
2207 BFD_ASSERT (abfd != NULL && ptr != NULL);
2209 /* Print normal ELF private data. */
2210 _bfd_elf_print_private_bfd_data (abfd, ptr);
2212 flags = elf_elfheader (abfd)->e_flags;
2213 /* Ignore init flag - it may not be set, despite the flags field
2214 containing valid data. */
2216 /* xgettext:c-format */
2217 fprintf (file, _("private flags = %lx:"), elf_elfheader (abfd)->e_flags);
2219 switch (EF_ARM_EABI_VERSION (flags))
2221 case EF_ARM_EABI_UNKNOWN:
2222 /* The following flag bits are GNU extenstions and not part of the
2223 official ARM ELF extended ABI. Hence they are only decoded if
2224 the EABI version is not set. */
2225 if (flags & EF_ARM_INTERWORK)
2226 fprintf (file, _(" [interworking enabled]"));
2228 if (flags & EF_ARM_APCS_26)
2229 fprintf (file, _(" [APCS-26]"));
2230 else
2231 fprintf (file, _(" [APCS-32]"));
2233 if (flags & EF_ARM_APCS_FLOAT)
2234 fprintf (file, _(" [floats passed in float registers]"));
2236 if (flags & EF_ARM_PIC)
2237 fprintf (file, _(" [position independent]"));
2239 if (flags & EF_ARM_NEW_ABI)
2240 fprintf (file, _(" [new ABI]"));
2242 if (flags & EF_ARM_OLD_ABI)
2243 fprintf (file, _(" [old ABI]"));
2245 if (flags & EF_ARM_SOFT_FLOAT)
2246 fprintf (file, _(" [software FP]"));
2248 flags &= ~(EF_ARM_INTERWORK | EF_ARM_APCS_26 | EF_ARM_APCS_FLOAT | EF_ARM_PIC
2249 | EF_ARM_NEW_ABI | EF_ARM_OLD_ABI | EF_ARM_SOFT_FLOAT);
2250 break;
2252 case EF_ARM_EABI_VER1:
2253 fprintf (file, _(" [Version1 EABI]"));
2255 if (flags & EF_ARM_SYMSARESORTED)
2256 fprintf (file, _(" [sorted symbol table]"));
2257 else
2258 fprintf (file, _(" [unsorted symbol table]"));
2260 flags &= ~ EF_ARM_SYMSARESORTED;
2261 break;
2263 case EF_ARM_EABI_VER2:
2264 fprintf (file, _(" [Version2 EABI]"));
2266 if (flags & EF_ARM_SYMSARESORTED)
2267 fprintf (file, _(" [sorted symbol table]"));
2268 else
2269 fprintf (file, _(" [unsorted symbol table]"));
2271 if (flags & EF_ARM_DYNSYMSUSESEGIDX)
2272 fprintf (file, _(" [dynamic symbols use segment index]"));
2274 if (flags & EF_ARM_MAPSYMSFIRST)
2275 fprintf (file, _(" [mapping symbols precede others]"));
2277 flags &= ~(EF_ARM_SYMSARESORTED | EF_ARM_DYNSYMSUSESEGIDX
2278 | EF_ARM_MAPSYMSFIRST);
2279 break;
2281 default:
2282 fprintf (file, _(" <EABI version unrecognised>"));
2283 break;
2286 flags &= ~ EF_ARM_EABIMASK;
2288 if (flags & EF_ARM_RELEXEC)
2289 fprintf (file, _(" [relocatable executable]"));
2291 if (flags & EF_ARM_HASENTRY)
2292 fprintf (file, _(" [has entry point]"));
2294 flags &= ~ (EF_ARM_RELEXEC | EF_ARM_HASENTRY);
2296 if (flags)
2297 fprintf (file, _("<Unrecognised flag bits set>"));
2299 fputc ('\n', file);
2301 return true;
2304 static int
2305 elf32_arm_get_symbol_type (elf_sym, type)
2306 Elf_Internal_Sym * elf_sym;
2307 int type;
2309 switch (ELF_ST_TYPE (elf_sym->st_info))
2311 case STT_ARM_TFUNC:
2312 return ELF_ST_TYPE (elf_sym->st_info);
2314 case STT_ARM_16BIT:
2315 /* If the symbol is not an object, return the STT_ARM_16BIT flag.
2316 This allows us to distinguish between data used by Thumb instructions
2317 and non-data (which is probably code) inside Thumb regions of an
2318 executable. */
2319 if (type != STT_OBJECT)
2320 return ELF_ST_TYPE (elf_sym->st_info);
2321 break;
2323 default:
2324 break;
2327 return type;
2330 static asection *
2331 elf32_arm_gc_mark_hook (abfd, info, rel, h, sym)
2332 bfd *abfd;
2333 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2334 Elf_Internal_Rela *rel;
2335 struct elf_link_hash_entry *h;
2336 Elf_Internal_Sym *sym;
2338 if (h != NULL)
2340 switch (ELF32_R_TYPE (rel->r_info))
2342 case R_ARM_GNU_VTINHERIT:
2343 case R_ARM_GNU_VTENTRY:
2344 break;
2346 default:
2347 switch (h->root.type)
2349 case bfd_link_hash_defined:
2350 case bfd_link_hash_defweak:
2351 return h->root.u.def.section;
2353 case bfd_link_hash_common:
2354 return h->root.u.c.p->section;
2356 default:
2357 break;
2361 else
2363 if (!(elf_bad_symtab (abfd)
2364 && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
2365 && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
2366 && sym->st_shndx != SHN_COMMON))
2368 return bfd_section_from_elf_index (abfd, sym->st_shndx);
2371 return NULL;
2374 /* Update the got entry reference counts for the section being removed. */
2376 static boolean
2377 elf32_arm_gc_sweep_hook (abfd, info, sec, relocs)
2378 bfd *abfd ATTRIBUTE_UNUSED;
2379 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2380 asection *sec ATTRIBUTE_UNUSED;
2381 const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
2383 /* We don't support garbage collection of GOT and PLT relocs yet. */
2384 return true;
2387 /* Look through the relocs for a section during the first phase. */
2389 static boolean
2390 elf32_arm_check_relocs (abfd, info, sec, relocs)
2391 bfd * abfd;
2392 struct bfd_link_info * info;
2393 asection * sec;
2394 const Elf_Internal_Rela * relocs;
2396 Elf_Internal_Shdr * symtab_hdr;
2397 struct elf_link_hash_entry ** sym_hashes;
2398 struct elf_link_hash_entry ** sym_hashes_end;
2399 const Elf_Internal_Rela * rel;
2400 const Elf_Internal_Rela * rel_end;
2401 bfd * dynobj;
2402 asection * sgot, *srelgot, *sreloc;
2403 bfd_vma * local_got_offsets;
2405 if (info->relocateable)
2406 return true;
2408 sgot = srelgot = sreloc = NULL;
2410 dynobj = elf_hash_table (info)->dynobj;
2411 local_got_offsets = elf_local_got_offsets (abfd);
2413 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2414 sym_hashes = elf_sym_hashes (abfd);
2415 sym_hashes_end = sym_hashes
2416 + symtab_hdr->sh_size / sizeof (Elf32_External_Sym);
2418 if (!elf_bad_symtab (abfd))
2419 sym_hashes_end -= symtab_hdr->sh_info;
2421 rel_end = relocs + sec->reloc_count;
2422 for (rel = relocs; rel < rel_end; rel++)
2424 struct elf_link_hash_entry *h;
2425 unsigned long r_symndx;
2427 r_symndx = ELF32_R_SYM (rel->r_info);
2428 if (r_symndx < symtab_hdr->sh_info)
2429 h = NULL;
2430 else
2431 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
2433 /* Some relocs require a global offset table. */
2434 if (dynobj == NULL)
2436 switch (ELF32_R_TYPE (rel->r_info))
2438 case R_ARM_GOT32:
2439 case R_ARM_GOTOFF:
2440 case R_ARM_GOTPC:
2441 elf_hash_table (info)->dynobj = dynobj = abfd;
2442 if (! _bfd_elf_create_got_section (dynobj, info))
2443 return false;
2444 break;
2446 default:
2447 break;
2451 switch (ELF32_R_TYPE (rel->r_info))
2453 case R_ARM_GOT32:
2454 /* This symbol requires a global offset table entry. */
2455 if (sgot == NULL)
2457 sgot = bfd_get_section_by_name (dynobj, ".got");
2458 BFD_ASSERT (sgot != NULL);
2461 /* Get the got relocation section if necessary. */
2462 if (srelgot == NULL
2463 && (h != NULL || info->shared))
2465 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
2467 /* If no got relocation section, make one and initialize. */
2468 if (srelgot == NULL)
2470 srelgot = bfd_make_section (dynobj, ".rel.got");
2471 if (srelgot == NULL
2472 || ! bfd_set_section_flags (dynobj, srelgot,
2473 (SEC_ALLOC
2474 | SEC_LOAD
2475 | SEC_HAS_CONTENTS
2476 | SEC_IN_MEMORY
2477 | SEC_LINKER_CREATED
2478 | SEC_READONLY))
2479 || ! bfd_set_section_alignment (dynobj, srelgot, 2))
2480 return false;
2484 if (h != NULL)
2486 if (h->got.offset != (bfd_vma) -1)
2487 /* We have already allocated space in the .got. */
2488 break;
2490 h->got.offset = sgot->_raw_size;
2492 /* Make sure this symbol is output as a dynamic symbol. */
2493 if (h->dynindx == -1)
2494 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2495 return false;
2497 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2499 else
2501 /* This is a global offset table entry for a local
2502 symbol. */
2503 if (local_got_offsets == NULL)
2505 size_t size;
2506 register unsigned int i;
2508 size = symtab_hdr->sh_info * sizeof (bfd_vma);
2509 local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
2510 if (local_got_offsets == NULL)
2511 return false;
2512 elf_local_got_offsets (abfd) = local_got_offsets;
2513 for (i = 0; i < symtab_hdr->sh_info; i++)
2514 local_got_offsets[i] = (bfd_vma) -1;
2517 if (local_got_offsets[r_symndx] != (bfd_vma) -1)
2518 /* We have already allocated space in the .got. */
2519 break;
2521 local_got_offsets[r_symndx] = sgot->_raw_size;
2523 if (info->shared)
2524 /* If we are generating a shared object, we need to
2525 output a R_ARM_RELATIVE reloc so that the dynamic
2526 linker can adjust this GOT entry. */
2527 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2530 sgot->_raw_size += 4;
2531 break;
2533 case R_ARM_PLT32:
2534 /* This symbol requires a procedure linkage table entry. We
2535 actually build the entry in adjust_dynamic_symbol,
2536 because this might be a case of linking PIC code which is
2537 never referenced by a dynamic object, in which case we
2538 don't need to generate a procedure linkage table entry
2539 after all. */
2541 /* If this is a local symbol, we resolve it directly without
2542 creating a procedure linkage table entry. */
2543 if (h == NULL)
2544 continue;
2546 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
2547 break;
2549 case R_ARM_ABS32:
2550 case R_ARM_REL32:
2551 case R_ARM_PC24:
2552 /* If we are creating a shared library, and this is a reloc
2553 against a global symbol, or a non PC relative reloc
2554 against a local symbol, then we need to copy the reloc
2555 into the shared library. However, if we are linking with
2556 -Bsymbolic, we do not need to copy a reloc against a
2557 global symbol which is defined in an object we are
2558 including in the link (i.e., DEF_REGULAR is set). At
2559 this point we have not seen all the input files, so it is
2560 possible that DEF_REGULAR is not set now but will be set
2561 later (it is never cleared). We account for that
2562 possibility below by storing information in the
2563 pcrel_relocs_copied field of the hash table entry. */
2564 if (info->shared
2565 && (ELF32_R_TYPE (rel->r_info) != R_ARM_PC24
2566 || (h != NULL
2567 && (! info->symbolic
2568 || (h->elf_link_hash_flags
2569 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
2571 /* When creating a shared object, we must copy these
2572 reloc types into the output file. We create a reloc
2573 section in dynobj and make room for this reloc. */
2574 if (sreloc == NULL)
2576 const char * name;
2578 name = (bfd_elf_string_from_elf_section
2579 (abfd,
2580 elf_elfheader (abfd)->e_shstrndx,
2581 elf_section_data (sec)->rel_hdr.sh_name));
2582 if (name == NULL)
2583 return false;
2585 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
2586 && strcmp (bfd_get_section_name (abfd, sec),
2587 name + 4) == 0);
2589 sreloc = bfd_get_section_by_name (dynobj, name);
2590 if (sreloc == NULL)
2592 flagword flags;
2594 sreloc = bfd_make_section (dynobj, name);
2595 flags = (SEC_HAS_CONTENTS | SEC_READONLY
2596 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2597 if ((sec->flags & SEC_ALLOC) != 0)
2598 flags |= SEC_ALLOC | SEC_LOAD;
2599 if (sreloc == NULL
2600 || ! bfd_set_section_flags (dynobj, sreloc, flags)
2601 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
2602 return false;
2606 sreloc->_raw_size += sizeof (Elf32_External_Rel);
2607 /* If we are linking with -Bsymbolic, and this is a
2608 global symbol, we count the number of PC relative
2609 relocations we have entered for this symbol, so that
2610 we can discard them again if the symbol is later
2611 defined by a regular object. Note that this function
2612 is only called if we are using an elf_i386 linker
2613 hash table, which means that h is really a pointer to
2614 an elf_i386_link_hash_entry. */
2615 if (h != NULL && info->symbolic
2616 && ELF32_R_TYPE (rel->r_info) == R_ARM_PC24)
2618 struct elf32_arm_link_hash_entry * eh;
2619 struct elf32_arm_pcrel_relocs_copied * p;
2621 eh = (struct elf32_arm_link_hash_entry *) h;
2623 for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
2624 if (p->section == sreloc)
2625 break;
2627 if (p == NULL)
2629 p = ((struct elf32_arm_pcrel_relocs_copied *)
2630 bfd_alloc (dynobj, sizeof * p));
2632 if (p == NULL)
2633 return false;
2634 p->next = eh->pcrel_relocs_copied;
2635 eh->pcrel_relocs_copied = p;
2636 p->section = sreloc;
2637 p->count = 0;
2640 ++p->count;
2643 break;
2645 /* This relocation describes the C++ object vtable hierarchy.
2646 Reconstruct it for later use during GC. */
2647 case R_ARM_GNU_VTINHERIT:
2648 if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
2649 return false;
2650 break;
2652 /* This relocation describes which C++ vtable entries are actually
2653 used. Record for later use during GC. */
2654 case R_ARM_GNU_VTENTRY:
2655 if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_offset))
2656 return false;
2657 break;
2661 return true;
2664 /* Find the nearest line to a particular section and offset, for error
2665 reporting. This code is a duplicate of the code in elf.c, except
2666 that it also accepts STT_ARM_TFUNC as a symbol that names a function. */
2668 static boolean
2669 elf32_arm_find_nearest_line
2670 (abfd, section, symbols, offset, filename_ptr, functionname_ptr, line_ptr)
2671 bfd * abfd;
2672 asection * section;
2673 asymbol ** symbols;
2674 bfd_vma offset;
2675 CONST char ** filename_ptr;
2676 CONST char ** functionname_ptr;
2677 unsigned int * line_ptr;
2679 boolean found;
2680 const char * filename;
2681 asymbol * func;
2682 bfd_vma low_func;
2683 asymbol ** p;
2685 if (_bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
2686 filename_ptr, functionname_ptr,
2687 line_ptr, 0,
2688 &elf_tdata (abfd)->dwarf2_find_line_info))
2689 return true;
2691 if (! _bfd_stab_section_find_nearest_line (abfd, symbols, section, offset,
2692 &found, filename_ptr,
2693 functionname_ptr, line_ptr,
2694 &elf_tdata (abfd)->line_info))
2695 return false;
2697 if (found)
2698 return true;
2700 if (symbols == NULL)
2701 return false;
2703 filename = NULL;
2704 func = NULL;
2705 low_func = 0;
2707 for (p = symbols; *p != NULL; p++)
2709 elf_symbol_type *q;
2711 q = (elf_symbol_type *) *p;
2713 if (bfd_get_section (&q->symbol) != section)
2714 continue;
2716 switch (ELF_ST_TYPE (q->internal_elf_sym.st_info))
2718 default:
2719 break;
2720 case STT_FILE:
2721 filename = bfd_asymbol_name (&q->symbol);
2722 break;
2723 case STT_NOTYPE:
2724 case STT_FUNC:
2725 case STT_ARM_TFUNC:
2726 if (q->symbol.section == section
2727 && q->symbol.value >= low_func
2728 && q->symbol.value <= offset)
2730 func = (asymbol *) q;
2731 low_func = q->symbol.value;
2733 break;
2737 if (func == NULL)
2738 return false;
2740 *filename_ptr = filename;
2741 *functionname_ptr = bfd_asymbol_name (func);
2742 *line_ptr = 0;
2744 return true;
2747 /* Adjust a symbol defined by a dynamic object and referenced by a
2748 regular object. The current definition is in some section of the
2749 dynamic object, but we're not including those sections. We have to
2750 change the definition to something the rest of the link can
2751 understand. */
2753 static boolean
2754 elf32_arm_adjust_dynamic_symbol (info, h)
2755 struct bfd_link_info * info;
2756 struct elf_link_hash_entry * h;
2758 bfd * dynobj;
2759 asection * s;
2760 unsigned int power_of_two;
2762 dynobj = elf_hash_table (info)->dynobj;
2764 /* Make sure we know what is going on here. */
2765 BFD_ASSERT (dynobj != NULL
2766 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
2767 || h->weakdef != NULL
2768 || ((h->elf_link_hash_flags
2769 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2770 && (h->elf_link_hash_flags
2771 & ELF_LINK_HASH_REF_REGULAR) != 0
2772 && (h->elf_link_hash_flags
2773 & ELF_LINK_HASH_DEF_REGULAR) == 0)));
2775 /* If this is a function, put it in the procedure linkage table. We
2776 will fill in the contents of the procedure linkage table later,
2777 when we know the address of the .got section. */
2778 if (h->type == STT_FUNC
2779 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
2781 if (! info->shared
2782 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2783 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
2785 /* This case can occur if we saw a PLT32 reloc in an input
2786 file, but the symbol was never referred to by a dynamic
2787 object. In such a case, we don't actually need to build
2788 a procedure linkage table, and we can just do a PC32
2789 reloc instead. */
2790 BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
2791 return true;
2794 /* Make sure this symbol is output as a dynamic symbol. */
2795 if (h->dynindx == -1)
2797 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2798 return false;
2801 s = bfd_get_section_by_name (dynobj, ".plt");
2802 BFD_ASSERT (s != NULL);
2804 /* If this is the first .plt entry, make room for the special
2805 first entry. */
2806 if (s->_raw_size == 0)
2807 s->_raw_size += PLT_ENTRY_SIZE;
2809 /* If this symbol is not defined in a regular file, and we are
2810 not generating a shared library, then set the symbol to this
2811 location in the .plt. This is required to make function
2812 pointers compare as equal between the normal executable and
2813 the shared library. */
2814 if (! info->shared
2815 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2817 h->root.u.def.section = s;
2818 h->root.u.def.value = s->_raw_size;
2821 h->plt.offset = s->_raw_size;
2823 /* Make room for this entry. */
2824 s->_raw_size += PLT_ENTRY_SIZE;
2826 /* We also need to make an entry in the .got.plt section, which
2827 will be placed in the .got section by the linker script. */
2828 s = bfd_get_section_by_name (dynobj, ".got.plt");
2829 BFD_ASSERT (s != NULL);
2830 s->_raw_size += 4;
2832 /* We also need to make an entry in the .rel.plt section. */
2834 s = bfd_get_section_by_name (dynobj, ".rel.plt");
2835 BFD_ASSERT (s != NULL);
2836 s->_raw_size += sizeof (Elf32_External_Rel);
2838 return true;
2841 /* If this is a weak symbol, and there is a real definition, the
2842 processor independent code will have arranged for us to see the
2843 real definition first, and we can just use the same value. */
2844 if (h->weakdef != NULL)
2846 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
2847 || h->weakdef->root.type == bfd_link_hash_defweak);
2848 h->root.u.def.section = h->weakdef->root.u.def.section;
2849 h->root.u.def.value = h->weakdef->root.u.def.value;
2850 return true;
2853 /* This is a reference to a symbol defined by a dynamic object which
2854 is not a function. */
2856 /* If we are creating a shared library, we must presume that the
2857 only references to the symbol are via the global offset table.
2858 For such cases we need not do anything here; the relocations will
2859 be handled correctly by relocate_section. */
2860 if (info->shared)
2861 return true;
2863 /* We must allocate the symbol in our .dynbss section, which will
2864 become part of the .bss section of the executable. There will be
2865 an entry for this symbol in the .dynsym section. The dynamic
2866 object will contain position independent code, so all references
2867 from the dynamic object to this symbol will go through the global
2868 offset table. The dynamic linker will use the .dynsym entry to
2869 determine the address it must put in the global offset table, so
2870 both the dynamic object and the regular object will refer to the
2871 same memory location for the variable. */
2872 s = bfd_get_section_by_name (dynobj, ".dynbss");
2873 BFD_ASSERT (s != NULL);
2875 /* We must generate a R_ARM_COPY reloc to tell the dynamic linker to
2876 copy the initial value out of the dynamic object and into the
2877 runtime process image. We need to remember the offset into the
2878 .rel.bss section we are going to use. */
2879 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
2881 asection *srel;
2883 srel = bfd_get_section_by_name (dynobj, ".rel.bss");
2884 BFD_ASSERT (srel != NULL);
2885 srel->_raw_size += sizeof (Elf32_External_Rel);
2886 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
2889 /* We need to figure out the alignment required for this symbol. I
2890 have no idea how ELF linkers handle this. */
2891 power_of_two = bfd_log2 (h->size);
2892 if (power_of_two > 3)
2893 power_of_two = 3;
2895 /* Apply the required alignment. */
2896 s->_raw_size = BFD_ALIGN (s->_raw_size,
2897 (bfd_size_type) (1 << power_of_two));
2898 if (power_of_two > bfd_get_section_alignment (dynobj, s))
2900 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
2901 return false;
2904 /* Define the symbol as being at this point in the section. */
2905 h->root.u.def.section = s;
2906 h->root.u.def.value = s->_raw_size;
2908 /* Increment the section size to make room for the symbol. */
2909 s->_raw_size += h->size;
2911 return true;
2914 /* Set the sizes of the dynamic sections. */
2916 static boolean
2917 elf32_arm_size_dynamic_sections (output_bfd, info)
2918 bfd * output_bfd;
2919 struct bfd_link_info * info;
2921 bfd * dynobj;
2922 asection * s;
2923 boolean plt;
2924 boolean relocs;
2925 boolean reltext;
2927 dynobj = elf_hash_table (info)->dynobj;
2928 BFD_ASSERT (dynobj != NULL);
2930 if (elf_hash_table (info)->dynamic_sections_created)
2932 /* Set the contents of the .interp section to the interpreter. */
2933 if (! info->shared)
2935 s = bfd_get_section_by_name (dynobj, ".interp");
2936 BFD_ASSERT (s != NULL);
2937 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
2938 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
2941 else
2943 /* We may have created entries in the .rel.got section.
2944 However, if we are not creating the dynamic sections, we will
2945 not actually use these entries. Reset the size of .rel.got,
2946 which will cause it to get stripped from the output file
2947 below. */
2948 s = bfd_get_section_by_name (dynobj, ".rel.got");
2949 if (s != NULL)
2950 s->_raw_size = 0;
2953 /* If this is a -Bsymbolic shared link, then we need to discard all
2954 PC relative relocs against symbols defined in a regular object.
2955 We allocated space for them in the check_relocs routine, but we
2956 will not fill them in in the relocate_section routine. */
2957 if (info->shared && info->symbolic)
2958 elf32_arm_link_hash_traverse (elf32_arm_hash_table (info),
2959 elf32_arm_discard_copies,
2960 (PTR) NULL);
2962 /* The check_relocs and adjust_dynamic_symbol entry points have
2963 determined the sizes of the various dynamic sections. Allocate
2964 memory for them. */
2965 plt = false;
2966 relocs = false;
2967 reltext = false;
2968 for (s = dynobj->sections; s != NULL; s = s->next)
2970 const char * name;
2971 boolean strip;
2973 if ((s->flags & SEC_LINKER_CREATED) == 0)
2974 continue;
2976 /* It's OK to base decisions on the section name, because none
2977 of the dynobj section names depend upon the input files. */
2978 name = bfd_get_section_name (dynobj, s);
2980 strip = false;
2982 if (strcmp (name, ".plt") == 0)
2984 if (s->_raw_size == 0)
2986 /* Strip this section if we don't need it; see the
2987 comment below. */
2988 strip = true;
2990 else
2992 /* Remember whether there is a PLT. */
2993 plt = true;
2996 else if (strncmp (name, ".rel", 4) == 0)
2998 if (s->_raw_size == 0)
3000 /* If we don't need this section, strip it from the
3001 output file. This is mostly to handle .rel.bss and
3002 .rel.plt. We must create both sections in
3003 create_dynamic_sections, because they must be created
3004 before the linker maps input sections to output
3005 sections. The linker does that before
3006 adjust_dynamic_symbol is called, and it is that
3007 function which decides whether anything needs to go
3008 into these sections. */
3009 strip = true;
3011 else
3013 asection * target;
3015 /* Remember whether there are any reloc sections other
3016 than .rel.plt. */
3017 if (strcmp (name, ".rel.plt") != 0)
3019 const char *outname;
3021 relocs = true;
3023 /* If this relocation section applies to a read only
3024 section, then we probably need a DT_TEXTREL
3025 entry. The entries in the .rel.plt section
3026 really apply to the .got section, which we
3027 created ourselves and so know is not readonly. */
3028 outname = bfd_get_section_name (output_bfd,
3029 s->output_section);
3030 target = bfd_get_section_by_name (output_bfd, outname + 4);
3032 if (target != NULL
3033 && (target->flags & SEC_READONLY) != 0
3034 && (target->flags & SEC_ALLOC) != 0)
3035 reltext = true;
3038 /* We use the reloc_count field as a counter if we need
3039 to copy relocs into the output file. */
3040 s->reloc_count = 0;
3043 else if (strncmp (name, ".got", 4) != 0)
3045 /* It's not one of our sections, so don't allocate space. */
3046 continue;
3049 if (strip)
3051 asection ** spp;
3053 for (spp = &s->output_section->owner->sections;
3054 *spp != s->output_section;
3055 spp = &(*spp)->next)
3057 *spp = s->output_section->next;
3058 --s->output_section->owner->section_count;
3060 continue;
3063 /* Allocate memory for the section contents. */
3064 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
3065 if (s->contents == NULL && s->_raw_size != 0)
3066 return false;
3069 if (elf_hash_table (info)->dynamic_sections_created)
3071 /* Add some entries to the .dynamic section. We fill in the
3072 values later, in elf32_arm_finish_dynamic_sections, but we
3073 must add the entries now so that we get the correct size for
3074 the .dynamic section. The DT_DEBUG entry is filled in by the
3075 dynamic linker and used by the debugger. */
3076 if (! info->shared)
3078 if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
3079 return false;
3082 if (plt)
3084 if ( ! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
3085 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
3086 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
3087 || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
3088 return false;
3091 if (relocs)
3093 if ( ! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
3094 || ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
3095 || ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
3096 sizeof (Elf32_External_Rel)))
3097 return false;
3100 if (reltext)
3102 if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
3103 return false;
3104 info->flags |= DF_TEXTREL;
3108 return true;
3111 /* This function is called via elf32_arm_link_hash_traverse if we are
3112 creating a shared object with -Bsymbolic. It discards the space
3113 allocated to copy PC relative relocs against symbols which are
3114 defined in regular objects. We allocated space for them in the
3115 check_relocs routine, but we won't fill them in in the
3116 relocate_section routine. */
3118 static boolean
3119 elf32_arm_discard_copies (h, ignore)
3120 struct elf32_arm_link_hash_entry * h;
3121 PTR ignore ATTRIBUTE_UNUSED;
3123 struct elf32_arm_pcrel_relocs_copied * s;
3125 /* We only discard relocs for symbols defined in a regular object. */
3126 if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3127 return true;
3129 for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
3130 s->section->_raw_size -= s->count * sizeof (Elf32_External_Rel);
3132 return true;
3135 /* Finish up dynamic symbol handling. We set the contents of various
3136 dynamic sections here. */
3138 static boolean
3139 elf32_arm_finish_dynamic_symbol (output_bfd, info, h, sym)
3140 bfd * output_bfd;
3141 struct bfd_link_info * info;
3142 struct elf_link_hash_entry * h;
3143 Elf_Internal_Sym * sym;
3145 bfd * dynobj;
3147 dynobj = elf_hash_table (info)->dynobj;
3149 if (h->plt.offset != (bfd_vma) -1)
3151 asection * splt;
3152 asection * sgot;
3153 asection * srel;
3154 bfd_vma plt_index;
3155 bfd_vma got_offset;
3156 Elf_Internal_Rel rel;
3158 /* This symbol has an entry in the procedure linkage table. Set
3159 it up. */
3161 BFD_ASSERT (h->dynindx != -1);
3163 splt = bfd_get_section_by_name (dynobj, ".plt");
3164 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
3165 srel = bfd_get_section_by_name (dynobj, ".rel.plt");
3166 BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
3168 /* Get the index in the procedure linkage table which
3169 corresponds to this symbol. This is the index of this symbol
3170 in all the symbols for which we are making plt entries. The
3171 first entry in the procedure linkage table is reserved. */
3172 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
3174 /* Get the offset into the .got table of the entry that
3175 corresponds to this function. Each .got entry is 4 bytes.
3176 The first three are reserved. */
3177 got_offset = (plt_index + 3) * 4;
3179 /* Fill in the entry in the procedure linkage table. */
3180 bfd_put_32 (output_bfd, elf32_arm_plt_entry[0],
3181 splt->contents + h->plt.offset + 0);
3182 bfd_put_32 (output_bfd, elf32_arm_plt_entry[1],
3183 splt->contents + h->plt.offset + 4);
3184 bfd_put_32 (output_bfd, elf32_arm_plt_entry[2],
3185 splt->contents + h->plt.offset + 8);
3186 bfd_put_32 (output_bfd,
3187 (sgot->output_section->vma
3188 + sgot->output_offset
3189 + got_offset
3190 - splt->output_section->vma
3191 - splt->output_offset
3192 - h->plt.offset - 12),
3193 splt->contents + h->plt.offset + 12);
3195 /* Fill in the entry in the global offset table. */
3196 bfd_put_32 (output_bfd,
3197 (splt->output_section->vma
3198 + splt->output_offset),
3199 sgot->contents + got_offset);
3201 /* Fill in the entry in the .rel.plt section. */
3202 rel.r_offset = (sgot->output_section->vma
3203 + sgot->output_offset
3204 + got_offset);
3205 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_JUMP_SLOT);
3206 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3207 ((Elf32_External_Rel *) srel->contents
3208 + plt_index));
3210 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3212 /* Mark the symbol as undefined, rather than as defined in
3213 the .plt section. Leave the value alone. */
3214 sym->st_shndx = SHN_UNDEF;
3215 /* If the symbol is weak, we do need to clear the value.
3216 Otherwise, the PLT entry would provide a definition for
3217 the symbol even if the symbol wasn't defined anywhere,
3218 and so the symbol would never be NULL. */
3219 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK)
3220 == 0)
3221 sym->st_value = 0;
3225 if (h->got.offset != (bfd_vma) -1)
3227 asection * sgot;
3228 asection * srel;
3229 Elf_Internal_Rel rel;
3231 /* This symbol has an entry in the global offset table. Set it
3232 up. */
3233 sgot = bfd_get_section_by_name (dynobj, ".got");
3234 srel = bfd_get_section_by_name (dynobj, ".rel.got");
3235 BFD_ASSERT (sgot != NULL && srel != NULL);
3237 rel.r_offset = (sgot->output_section->vma
3238 + sgot->output_offset
3239 + (h->got.offset &~ 1));
3241 /* If this is a -Bsymbolic link, and the symbol is defined
3242 locally, we just want to emit a RELATIVE reloc. The entry in
3243 the global offset table will already have been initialized in
3244 the relocate_section function. */
3245 if (info->shared
3246 && (info->symbolic || h->dynindx == -1)
3247 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
3248 rel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
3249 else
3251 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
3252 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_GLOB_DAT);
3255 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3256 ((Elf32_External_Rel *) srel->contents
3257 + srel->reloc_count));
3258 ++srel->reloc_count;
3261 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
3263 asection * s;
3264 Elf_Internal_Rel rel;
3266 /* This symbol needs a copy reloc. Set it up. */
3267 BFD_ASSERT (h->dynindx != -1
3268 && (h->root.type == bfd_link_hash_defined
3269 || h->root.type == bfd_link_hash_defweak));
3271 s = bfd_get_section_by_name (h->root.u.def.section->owner,
3272 ".rel.bss");
3273 BFD_ASSERT (s != NULL);
3275 rel.r_offset = (h->root.u.def.value
3276 + h->root.u.def.section->output_section->vma
3277 + h->root.u.def.section->output_offset);
3278 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_COPY);
3279 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3280 ((Elf32_External_Rel *) s->contents
3281 + s->reloc_count));
3282 ++s->reloc_count;
3285 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3286 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3287 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
3288 sym->st_shndx = SHN_ABS;
3290 return true;
3293 /* Finish up the dynamic sections. */
3295 static boolean
3296 elf32_arm_finish_dynamic_sections (output_bfd, info)
3297 bfd * output_bfd;
3298 struct bfd_link_info * info;
3300 bfd * dynobj;
3301 asection * sgot;
3302 asection * sdyn;
3304 dynobj = elf_hash_table (info)->dynobj;
3306 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
3307 BFD_ASSERT (sgot != NULL);
3308 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3310 if (elf_hash_table (info)->dynamic_sections_created)
3312 asection *splt;
3313 Elf32_External_Dyn *dyncon, *dynconend;
3315 splt = bfd_get_section_by_name (dynobj, ".plt");
3316 BFD_ASSERT (splt != NULL && sdyn != NULL);
3318 dyncon = (Elf32_External_Dyn *) sdyn->contents;
3319 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
3321 for (; dyncon < dynconend; dyncon++)
3323 Elf_Internal_Dyn dyn;
3324 const char * name;
3325 asection * s;
3327 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
3329 switch (dyn.d_tag)
3331 default:
3332 break;
3334 case DT_PLTGOT:
3335 name = ".got";
3336 goto get_vma;
3337 case DT_JMPREL:
3338 name = ".rel.plt";
3339 get_vma:
3340 s = bfd_get_section_by_name (output_bfd, name);
3341 BFD_ASSERT (s != NULL);
3342 dyn.d_un.d_ptr = s->vma;
3343 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3344 break;
3346 case DT_PLTRELSZ:
3347 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3348 BFD_ASSERT (s != NULL);
3349 if (s->_cooked_size != 0)
3350 dyn.d_un.d_val = s->_cooked_size;
3351 else
3352 dyn.d_un.d_val = s->_raw_size;
3353 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3354 break;
3356 case DT_RELSZ:
3357 /* My reading of the SVR4 ABI indicates that the
3358 procedure linkage table relocs (DT_JMPREL) should be
3359 included in the overall relocs (DT_REL). This is
3360 what Solaris does. However, UnixWare can not handle
3361 that case. Therefore, we override the DT_RELSZ entry
3362 here to make it not include the JMPREL relocs. Since
3363 the linker script arranges for .rel.plt to follow all
3364 other relocation sections, we don't have to worry
3365 about changing the DT_REL entry. */
3366 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3367 if (s != NULL)
3369 if (s->_cooked_size != 0)
3370 dyn.d_un.d_val -= s->_cooked_size;
3371 else
3372 dyn.d_un.d_val -= s->_raw_size;
3374 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3375 break;
3379 /* Fill in the first entry in the procedure linkage table. */
3380 if (splt->_raw_size > 0)
3382 bfd_put_32 (output_bfd, elf32_arm_plt0_entry[0], splt->contents + 0);
3383 bfd_put_32 (output_bfd, elf32_arm_plt0_entry[1], splt->contents + 4);
3384 bfd_put_32 (output_bfd, elf32_arm_plt0_entry[2], splt->contents + 8);
3385 bfd_put_32 (output_bfd, elf32_arm_plt0_entry[3], splt->contents + 12);
3388 /* UnixWare sets the entsize of .plt to 4, although that doesn't
3389 really seem like the right value. */
3390 elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
3393 /* Fill in the first three entries in the global offset table. */
3394 if (sgot->_raw_size > 0)
3396 if (sdyn == NULL)
3397 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
3398 else
3399 bfd_put_32 (output_bfd,
3400 sdyn->output_section->vma + sdyn->output_offset,
3401 sgot->contents);
3402 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
3403 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
3406 elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
3408 return true;
3411 static void
3412 elf32_arm_post_process_headers (abfd, link_info)
3413 bfd * abfd;
3414 struct bfd_link_info * link_info ATTRIBUTE_UNUSED;
3416 Elf_Internal_Ehdr * i_ehdrp; /* ELF file header, internal form. */
3418 i_ehdrp = elf_elfheader (abfd);
3420 i_ehdrp->e_ident[EI_OSABI] = ARM_ELF_OS_ABI_VERSION;
3421 i_ehdrp->e_ident[EI_ABIVERSION] = ARM_ELF_ABI_VERSION;
3424 #define ELF_ARCH bfd_arch_arm
3425 #define ELF_MACHINE_CODE EM_ARM
3426 #define ELF_MAXPAGESIZE 0x8000
3428 #define bfd_elf32_bfd_copy_private_bfd_data elf32_arm_copy_private_bfd_data
3429 #define bfd_elf32_bfd_merge_private_bfd_data elf32_arm_merge_private_bfd_data
3430 #define bfd_elf32_bfd_set_private_flags elf32_arm_set_private_flags
3431 #define bfd_elf32_bfd_print_private_bfd_data elf32_arm_print_private_bfd_data
3432 #define bfd_elf32_bfd_link_hash_table_create elf32_arm_link_hash_table_create
3433 #define bfd_elf32_bfd_reloc_type_lookup elf32_arm_reloc_type_lookup
3434 #define bfd_elf32_find_nearest_line elf32_arm_find_nearest_line
3436 #define elf_backend_get_symbol_type elf32_arm_get_symbol_type
3437 #define elf_backend_gc_mark_hook elf32_arm_gc_mark_hook
3438 #define elf_backend_gc_sweep_hook elf32_arm_gc_sweep_hook
3439 #define elf_backend_check_relocs elf32_arm_check_relocs
3440 #define elf_backend_relocate_section elf32_arm_relocate_section
3441 #define elf_backend_adjust_dynamic_symbol elf32_arm_adjust_dynamic_symbol
3442 #define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
3443 #define elf_backend_finish_dynamic_symbol elf32_arm_finish_dynamic_symbol
3444 #define elf_backend_finish_dynamic_sections elf32_arm_finish_dynamic_sections
3445 #define elf_backend_size_dynamic_sections elf32_arm_size_dynamic_sections
3446 #define elf_backend_post_process_headers elf32_arm_post_process_headers
3448 #define elf_backend_can_gc_sections 1
3449 #define elf_backend_plt_readonly 1
3450 #define elf_backend_want_got_plt 1
3451 #define elf_backend_want_plt_sym 0
3453 #define elf_backend_got_header_size 12
3454 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
3456 #include "elf32-target.h"