Update address for bug reports.
[binutils.git] / bfd / elf32-arm.h
blobabda34ddbe999ed70ac60cd3aeca2632c22463e6
1 /* 32-bit ELF support for ARM
2 Copyright 1998, 1999, 2000 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_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 bfd_byte elf32_arm_plt0_entry [PLT_ENTRY_SIZE] =
83 0x04, 0xe0, 0x2d, 0xe5, /* str lr, [sp, #-4]! */
84 0x10, 0xe0, 0x9f, 0xe5, /* ldr lr, [pc, #16] */
85 0x0e, 0xe0, 0x8f, 0xe0, /* adr lr, pc, lr */
86 0x08, 0xf0, 0xbe, 0xe5 /* ldr pc, [lr, #8]! */
89 /* Subsequent entries in a procedure linkage table look like
90 this. */
91 static const bfd_byte elf32_arm_plt_entry [PLT_ENTRY_SIZE] =
93 0x04, 0xc0, 0x9f, 0xe5, /* ldr ip, [pc, #4] */
94 0x0c, 0xc0, 0x8f, 0xe0, /* add ip, pc, ip */
95 0x00, 0xf0, 0x9c, 0xe5, /* ldr pc, [ip] */
96 0x00, 0x00, 0x00, 0x00 /* 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 globals = elf32_arm_hash_table (info);
1024 dynobj = elf_hash_table (info)->dynobj;
1025 if (dynobj)
1027 sgot = bfd_get_section_by_name (dynobj, ".got");
1028 splt = bfd_get_section_by_name (dynobj, ".plt");
1030 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1031 sym_hashes = elf_sym_hashes (input_bfd);
1032 local_got_offsets = elf_local_got_offsets (input_bfd);
1033 r_symndx = ELF32_R_SYM (rel->r_info);
1035 #ifdef USE_REL
1036 addend = bfd_get_32 (input_bfd, hit_data) & howto->src_mask;
1038 if (addend & ((howto->src_mask + 1) >> 1))
1040 signed_addend = -1;
1041 signed_addend &= ~ howto->src_mask;
1042 signed_addend |= addend;
1044 else
1045 signed_addend = addend;
1046 #else
1047 addend = signed_addend = rel->r_addend;
1048 #endif
1050 switch (r_type)
1052 case R_ARM_NONE:
1053 return bfd_reloc_ok;
1055 case R_ARM_PC24:
1056 case R_ARM_ABS32:
1057 case R_ARM_REL32:
1058 #ifndef OLD_ARM_ABI
1059 case R_ARM_XPC25:
1060 #endif
1061 /* When generating a shared object, these relocations are copied
1062 into the output file to be resolved at run time. */
1063 if (info->shared
1064 && (r_type != R_ARM_PC24
1065 || (h != NULL
1066 && h->dynindx != -1
1067 && (! info->symbolic
1068 || (h->elf_link_hash_flags
1069 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1071 Elf_Internal_Rel outrel;
1072 boolean skip, relocate;
1074 if (sreloc == NULL)
1076 const char * name;
1078 name = (bfd_elf_string_from_elf_section
1079 (input_bfd,
1080 elf_elfheader (input_bfd)->e_shstrndx,
1081 elf_section_data (input_section)->rel_hdr.sh_name));
1082 if (name == NULL)
1083 return bfd_reloc_notsupported;
1085 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
1086 && strcmp (bfd_get_section_name (input_bfd,
1087 input_section),
1088 name + 4) == 0);
1090 sreloc = bfd_get_section_by_name (dynobj, name);
1091 BFD_ASSERT (sreloc != NULL);
1094 skip = false;
1096 if (elf_section_data (input_section)->stab_info == NULL)
1097 outrel.r_offset = rel->r_offset;
1098 else
1100 bfd_vma off;
1102 off = (_bfd_stab_section_offset
1103 (output_bfd, &elf_hash_table (info)->stab_info,
1104 input_section,
1105 & elf_section_data (input_section)->stab_info,
1106 rel->r_offset));
1107 if (off == (bfd_vma) -1)
1108 skip = true;
1109 outrel.r_offset = off;
1112 outrel.r_offset += (input_section->output_section->vma
1113 + input_section->output_offset);
1115 if (skip)
1117 memset (&outrel, 0, sizeof outrel);
1118 relocate = false;
1120 else if (r_type == R_ARM_PC24)
1122 BFD_ASSERT (h != NULL && h->dynindx != -1);
1123 if ((input_section->flags & SEC_ALLOC) != 0)
1124 relocate = false;
1125 else
1126 relocate = true;
1127 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_PC24);
1129 else
1131 if (h == NULL
1132 || ((info->symbolic || h->dynindx == -1)
1133 && (h->elf_link_hash_flags
1134 & ELF_LINK_HASH_DEF_REGULAR) != 0))
1136 relocate = true;
1137 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1139 else
1141 BFD_ASSERT (h->dynindx != -1);
1142 if ((input_section->flags & SEC_ALLOC) != 0)
1143 relocate = false;
1144 else
1145 relocate = true;
1146 outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_ABS32);
1150 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1151 (((Elf32_External_Rel *)
1152 sreloc->contents)
1153 + sreloc->reloc_count));
1154 ++sreloc->reloc_count;
1156 /* If this reloc is against an external symbol, we do not want to
1157 fiddle with the addend. Otherwise, we need to include the symbol
1158 value so that it becomes an addend for the dynamic reloc. */
1159 if (! relocate)
1160 return bfd_reloc_ok;
1162 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1163 contents, rel->r_offset, value,
1164 (bfd_vma) 0);
1166 else switch (r_type)
1168 #ifndef OLD_ARM_ABI
1169 case R_ARM_XPC25: /* Arm BLX instruction. */
1170 #endif
1171 case R_ARM_PC24: /* Arm B/BL instruction */
1172 #ifndef OLD_ARM_ABI
1173 if (r_type == R_ARM_XPC25)
1175 /* Check for Arm calling Arm function. */
1176 /* FIXME: Should we translate the instruction into a BL
1177 instruction instead ? */
1178 if (sym_flags != STT_ARM_TFUNC)
1179 _bfd_error_handler (_("\
1180 %s: Warning: Arm BLX instruction targets Arm function '%s'."),
1181 bfd_get_filename (input_bfd),
1182 h ? h->root.root.string : "(local)");
1184 else
1185 #endif
1187 /* Check for Arm calling Thumb function. */
1188 if (sym_flags == STT_ARM_TFUNC)
1190 elf32_arm_to_thumb_stub (info, sym_name, input_bfd, output_bfd,
1191 input_section, hit_data, sym_sec, rel->r_offset,
1192 signed_addend, value);
1193 return bfd_reloc_ok;
1197 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1198 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0)
1200 /* The old way of doing things. Trearing the addend as a
1201 byte sized field and adding in the pipeline offset. */
1202 value -= (input_section->output_section->vma
1203 + input_section->output_offset);
1204 value -= rel->r_offset;
1205 value += addend;
1207 if (! globals->no_pipeline_knowledge)
1208 value -= 8;
1210 else
1212 /* The ARM ELF ABI says that this reloc is computed as: S - P + A
1213 where:
1214 S is the address of the symbol in the relocation.
1215 P is address of the instruction being relocated.
1216 A is the addend (extracted from the instruction) in bytes.
1218 S is held in 'value'.
1219 P is the base address of the section containing the instruction
1220 plus the offset of the reloc into that section, ie:
1221 (input_section->output_section->vma +
1222 input_section->output_offset +
1223 rel->r_offset).
1224 A is the addend, converted into bytes, ie:
1225 (signed_addend * 4)
1227 Note: None of these operations have knowledge of the pipeline
1228 size of the processor, thus it is up to the assembler to encode
1229 this information into the addend. */
1230 value -= (input_section->output_section->vma
1231 + input_section->output_offset);
1232 value -= rel->r_offset;
1233 value += (signed_addend << howto->size);
1235 /* Previous versions of this code also used to add in the pipeline
1236 offset here. This is wrong because the linker is not supposed
1237 to know about such things, and one day it might change. In order
1238 to support old binaries that need the old behaviour however, so
1239 we attempt to detect which ABI was used to create the reloc. */
1240 if (! globals->no_pipeline_knowledge)
1242 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form */
1244 i_ehdrp = elf_elfheader (input_bfd);
1246 if (i_ehdrp->e_ident[EI_OSABI] == 0)
1247 value -= 8;
1251 signed_addend = value;
1252 signed_addend >>= howto->rightshift;
1254 /* It is not an error for an undefined weak reference to be
1255 out of range. Any program that branches to such a symbol
1256 is going to crash anyway, so there is no point worrying
1257 about getting the destination exactly right. */
1258 if (! h || h->root.type != bfd_link_hash_undefweak)
1260 /* Perform a signed range check. */
1261 if ( signed_addend > ((bfd_signed_vma) (howto->dst_mask >> 1))
1262 || signed_addend < - ((bfd_signed_vma) ((howto->dst_mask + 1) >> 1)))
1263 return bfd_reloc_overflow;
1266 #ifndef OLD_ARM_ABI
1267 /* If necessary set the H bit in the BLX instruction. */
1268 if (r_type == R_ARM_XPC25 && ((value & 2) == 2))
1269 value = (signed_addend & howto->dst_mask)
1270 | (bfd_get_32 (input_bfd, hit_data) & (~ howto->dst_mask))
1271 | (1 << 24);
1272 else
1273 #endif
1274 value = (signed_addend & howto->dst_mask)
1275 | (bfd_get_32 (input_bfd, hit_data) & (~ howto->dst_mask));
1276 break;
1278 case R_ARM_ABS32:
1279 value += addend;
1280 if (sym_flags == STT_ARM_TFUNC)
1281 value |= 1;
1282 break;
1284 case R_ARM_REL32:
1285 value -= (input_section->output_section->vma
1286 + input_section->output_offset);
1287 value += addend;
1288 break;
1291 bfd_put_32 (input_bfd, value, hit_data);
1292 return bfd_reloc_ok;
1294 case R_ARM_ABS8:
1295 value += addend;
1296 if ((long) value > 0x7f || (long) value < -0x80)
1297 return bfd_reloc_overflow;
1299 bfd_put_8 (input_bfd, value, hit_data);
1300 return bfd_reloc_ok;
1302 case R_ARM_ABS16:
1303 value += addend;
1305 if ((long) value > 0x7fff || (long) value < -0x8000)
1306 return bfd_reloc_overflow;
1308 bfd_put_16 (input_bfd, value, hit_data);
1309 return bfd_reloc_ok;
1311 case R_ARM_ABS12:
1312 /* Support ldr and str instruction for the arm */
1313 /* Also thumb b (unconditional branch). ??? Really? */
1314 value += addend;
1316 if ((long) value > 0x7ff || (long) value < -0x800)
1317 return bfd_reloc_overflow;
1319 value |= (bfd_get_32 (input_bfd, hit_data) & 0xfffff000);
1320 bfd_put_32 (input_bfd, value, hit_data);
1321 return bfd_reloc_ok;
1323 case R_ARM_THM_ABS5:
1324 /* Support ldr and str instructions for the thumb. */
1325 #ifdef USE_REL
1326 /* Need to refetch addend. */
1327 addend = bfd_get_16 (input_bfd, hit_data) & howto->src_mask;
1328 /* ??? Need to determine shift amount from operand size. */
1329 addend >>= howto->rightshift;
1330 #endif
1331 value += addend;
1333 /* ??? Isn't value unsigned? */
1334 if ((long) value > 0x1f || (long) value < -0x10)
1335 return bfd_reloc_overflow;
1337 /* ??? Value needs to be properly shifted into place first. */
1338 value |= bfd_get_16 (input_bfd, hit_data) & 0xf83f;
1339 bfd_put_16 (input_bfd, value, hit_data);
1340 return bfd_reloc_ok;
1342 #ifndef OLD_ARM_ABI
1343 case R_ARM_THM_XPC22:
1344 #endif
1345 case R_ARM_THM_PC22:
1346 /* Thumb BL (branch long instruction). */
1348 bfd_vma relocation;
1349 boolean overflow = false;
1350 bfd_vma upper_insn = bfd_get_16 (input_bfd, hit_data);
1351 bfd_vma lower_insn = bfd_get_16 (input_bfd, hit_data + 2);
1352 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
1353 bfd_signed_vma reloc_signed_min = ~ reloc_signed_max;
1354 bfd_vma check;
1355 bfd_signed_vma signed_check;
1357 #ifdef USE_REL
1358 /* Need to refetch the addend and squish the two 11 bit pieces
1359 together. */
1361 bfd_vma upper = upper_insn & 0x7ff;
1362 bfd_vma lower = lower_insn & 0x7ff;
1363 upper = (upper ^ 0x400) - 0x400; /* Sign extend. */
1364 addend = (upper << 12) | (lower << 1);
1365 signed_addend = addend;
1367 #endif
1368 #ifndef OLD_ARM_ABI
1369 if (r_type == R_ARM_THM_XPC22)
1371 /* Check for Thumb to Thumb call. */
1372 /* FIXME: Should we translate the instruction into a BL
1373 instruction instead ? */
1374 if (sym_flags == STT_ARM_TFUNC)
1375 _bfd_error_handler (_("\
1376 %s: Warning: Thumb BLX instruction targets thumb function '%s'."),
1377 bfd_get_filename (input_bfd),
1378 h ? h->root.root.string : "(local)");
1380 else
1381 #endif
1383 /* If it is not a call to Thumb, assume call to Arm.
1384 If it is a call relative to a section name, then it is not a
1385 function call at all, but rather a long jump. */
1386 if (sym_flags != STT_ARM_TFUNC && sym_flags != STT_SECTION)
1388 if (elf32_thumb_to_arm_stub
1389 (info, sym_name, input_bfd, output_bfd, input_section,
1390 hit_data, sym_sec, rel->r_offset, signed_addend, value))
1391 return bfd_reloc_ok;
1392 else
1393 return bfd_reloc_dangerous;
1397 relocation = value + signed_addend;
1399 relocation -= (input_section->output_section->vma
1400 + input_section->output_offset
1401 + rel->r_offset);
1403 if (! globals->no_pipeline_knowledge)
1405 Elf_Internal_Ehdr * i_ehdrp; /* Elf file header, internal form. */
1407 i_ehdrp = elf_elfheader (input_bfd);
1409 /* Previous versions of this code also used to add in the pipline
1410 offset here. This is wrong because the linker is not supposed
1411 to know about such things, and one day it might change. In order
1412 to support old binaries that need the old behaviour however, so
1413 we attempt to detect which ABI was used to create the reloc. */
1414 if ( strcmp (bfd_get_target (input_bfd), "elf32-littlearm-oabi") == 0
1415 || strcmp (bfd_get_target (input_bfd), "elf32-bigarm-oabi") == 0
1416 || i_ehdrp->e_ident[EI_OSABI] == 0)
1417 relocation += 4;
1420 check = relocation >> howto->rightshift;
1422 /* If this is a signed value, the rightshift just dropped
1423 leading 1 bits (assuming twos complement). */
1424 if ((bfd_signed_vma) relocation >= 0)
1425 signed_check = check;
1426 else
1427 signed_check = check | ~((bfd_vma) -1 >> howto->rightshift);
1429 /* Assumes two's complement. */
1430 if (signed_check > reloc_signed_max || signed_check < reloc_signed_min)
1431 overflow = true;
1433 /* Put RELOCATION back into the insn. */
1434 upper_insn = (upper_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 12) & 0x7ff);
1435 lower_insn = (lower_insn & ~(bfd_vma) 0x7ff) | ((relocation >> 1) & 0x7ff);
1437 /* Put the relocated value back in the object file: */
1438 bfd_put_16 (input_bfd, upper_insn, hit_data);
1439 bfd_put_16 (input_bfd, lower_insn, hit_data + 2);
1441 return (overflow ? bfd_reloc_overflow : bfd_reloc_ok);
1443 break;
1445 case R_ARM_GNU_VTINHERIT:
1446 case R_ARM_GNU_VTENTRY:
1447 return bfd_reloc_ok;
1449 case R_ARM_COPY:
1450 return bfd_reloc_notsupported;
1452 case R_ARM_GLOB_DAT:
1453 return bfd_reloc_notsupported;
1455 case R_ARM_JUMP_SLOT:
1456 return bfd_reloc_notsupported;
1458 case R_ARM_RELATIVE:
1459 return bfd_reloc_notsupported;
1461 case R_ARM_GOTOFF:
1462 /* Relocation is relative to the start of the
1463 global offset table. */
1465 BFD_ASSERT (sgot != NULL);
1466 if (sgot == NULL)
1467 return bfd_reloc_notsupported;
1469 /* Note that sgot->output_offset is not involved in this
1470 calculation. We always want the start of .got. If we
1471 define _GLOBAL_OFFSET_TABLE in a different way, as is
1472 permitted by the ABI, we might have to change this
1473 calculation. */
1474 value -= sgot->output_section->vma;
1475 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1476 contents, rel->r_offset, value,
1477 (bfd_vma) 0);
1479 case R_ARM_GOTPC:
1480 /* Use global offset table as symbol value. */
1481 BFD_ASSERT (sgot != NULL);
1483 if (sgot == NULL)
1484 return bfd_reloc_notsupported;
1486 value = sgot->output_section->vma;
1487 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1488 contents, rel->r_offset, value,
1489 (bfd_vma) 0);
1491 case R_ARM_GOT32:
1492 /* Relocation is to the entry for this symbol in the
1493 global offset table. */
1494 if (sgot == NULL)
1495 return bfd_reloc_notsupported;
1497 if (h != NULL)
1499 bfd_vma off;
1501 off = h->got.offset;
1502 BFD_ASSERT (off != (bfd_vma) -1);
1504 if (!elf_hash_table (info)->dynamic_sections_created ||
1505 (info->shared && (info->symbolic || h->dynindx == -1)
1506 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1508 /* This is actually a static link, or it is a -Bsymbolic link
1509 and the symbol is defined locally. We must initialize this
1510 entry in the global offset table. Since the offset must
1511 always be a multiple of 4, we use the least significant bit
1512 to record whether we have initialized it already.
1514 When doing a dynamic link, we create a .rel.got relocation
1515 entry to initialize the value. This is done in the
1516 finish_dynamic_symbol routine. */
1517 if ((off & 1) != 0)
1518 off &= ~1;
1519 else
1521 bfd_put_32 (output_bfd, value, sgot->contents + off);
1522 h->got.offset |= 1;
1526 value = sgot->output_offset + off;
1528 else
1530 bfd_vma off;
1532 BFD_ASSERT (local_got_offsets != NULL &&
1533 local_got_offsets[r_symndx] != (bfd_vma) -1);
1535 off = local_got_offsets[r_symndx];
1537 /* The offset must always be a multiple of 4. We use the
1538 least significant bit to record whether we have already
1539 generated the necessary reloc. */
1540 if ((off & 1) != 0)
1541 off &= ~1;
1542 else
1544 bfd_put_32 (output_bfd, value, sgot->contents + off);
1546 if (info->shared)
1548 asection * srelgot;
1549 Elf_Internal_Rel outrel;
1551 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
1552 BFD_ASSERT (srelgot != NULL);
1554 outrel.r_offset = (sgot->output_section->vma
1555 + sgot->output_offset
1556 + off);
1557 outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
1558 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1559 (((Elf32_External_Rel *)
1560 srelgot->contents)
1561 + srelgot->reloc_count));
1562 ++srelgot->reloc_count;
1565 local_got_offsets[r_symndx] |= 1;
1568 value = sgot->output_offset + off;
1571 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1572 contents, rel->r_offset, value,
1573 (bfd_vma) 0);
1575 case R_ARM_PLT32:
1576 /* Relocation is to the entry for this symbol in the
1577 procedure linkage table. */
1579 /* Resolve a PLT32 reloc against a local symbol directly,
1580 without using the procedure linkage table. */
1581 if (h == NULL)
1582 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1583 contents, rel->r_offset, value,
1584 (bfd_vma) 0);
1586 if (h->plt.offset == (bfd_vma) -1)
1587 /* We didn't make a PLT entry for this symbol. This
1588 happens when statically linking PIC code, or when
1589 using -Bsymbolic. */
1590 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1591 contents, rel->r_offset, value,
1592 (bfd_vma) 0);
1594 BFD_ASSERT(splt != NULL);
1595 if (splt == NULL)
1596 return bfd_reloc_notsupported;
1598 value = (splt->output_section->vma
1599 + splt->output_offset
1600 + h->plt.offset);
1601 return _bfd_final_link_relocate (howto, input_bfd, input_section,
1602 contents, rel->r_offset, value,
1603 (bfd_vma) 0);
1605 case R_ARM_SBREL32:
1606 return bfd_reloc_notsupported;
1608 case R_ARM_AMP_VCALL9:
1609 return bfd_reloc_notsupported;
1611 case R_ARM_RSBREL32:
1612 return bfd_reloc_notsupported;
1614 case R_ARM_THM_RPC22:
1615 return bfd_reloc_notsupported;
1617 case R_ARM_RREL32:
1618 return bfd_reloc_notsupported;
1620 case R_ARM_RABS32:
1621 return bfd_reloc_notsupported;
1623 case R_ARM_RPC24:
1624 return bfd_reloc_notsupported;
1626 case R_ARM_RBASE:
1627 return bfd_reloc_notsupported;
1629 default:
1630 return bfd_reloc_notsupported;
1634 #ifdef USE_REL
1635 /* Add INCREMENT to the reloc (of type HOWTO) at ADDRESS. */
1636 static void
1637 arm_add_to_rel (abfd, address, howto, increment)
1638 bfd * abfd;
1639 bfd_byte * address;
1640 reloc_howto_type * howto;
1641 bfd_signed_vma increment;
1643 bfd_signed_vma addend;
1645 if (howto->type == R_ARM_THM_PC22)
1647 int upper_insn, lower_insn;
1648 int upper, lower;
1650 upper_insn = bfd_get_16 (abfd, address);
1651 lower_insn = bfd_get_16 (abfd, address + 2);
1652 upper = upper_insn & 0x7ff;
1653 lower = lower_insn & 0x7ff;
1655 addend = (upper << 12) | (lower << 1);
1656 addend += increment;
1657 addend >>= 1;
1659 upper_insn = (upper_insn & 0xf800) | ((addend >> 11) & 0x7ff);
1660 lower_insn = (lower_insn & 0xf800) | (addend & 0x7ff);
1662 bfd_put_16 (abfd, upper_insn, address);
1663 bfd_put_16 (abfd, lower_insn, address + 2);
1665 else
1667 bfd_vma contents;
1669 contents = bfd_get_32 (abfd, address);
1671 /* Get the (signed) value from the instruction. */
1672 addend = contents & howto->src_mask;
1673 if (addend & ((howto->src_mask + 1) >> 1))
1675 bfd_signed_vma mask;
1677 mask = -1;
1678 mask &= ~ howto->src_mask;
1679 addend |= mask;
1682 /* Add in the increment, (which is a byte value). */
1683 switch (howto->type)
1685 default:
1686 addend += increment;
1687 break;
1689 case R_ARM_PC24:
1690 addend <<= howto->size;
1691 addend += increment;
1693 /* Should we check for overflow here ? */
1695 /* Drop any undesired bits. */
1696 addend >>= howto->rightshift;
1697 break;
1700 contents = (contents & ~ howto->dst_mask) | (addend & howto->dst_mask);
1702 bfd_put_32 (abfd, contents, address);
1705 #endif /* USE_REL */
1707 /* Relocate an ARM ELF section. */
1708 static boolean
1709 elf32_arm_relocate_section (output_bfd, info, input_bfd, input_section,
1710 contents, relocs, local_syms, local_sections)
1711 bfd * output_bfd;
1712 struct bfd_link_info * info;
1713 bfd * input_bfd;
1714 asection * input_section;
1715 bfd_byte * contents;
1716 Elf_Internal_Rela * relocs;
1717 Elf_Internal_Sym * local_syms;
1718 asection ** local_sections;
1720 Elf_Internal_Shdr * symtab_hdr;
1721 struct elf_link_hash_entry ** sym_hashes;
1722 Elf_Internal_Rela * rel;
1723 Elf_Internal_Rela * relend;
1724 const char * name;
1726 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1727 sym_hashes = elf_sym_hashes (input_bfd);
1729 rel = relocs;
1730 relend = relocs + input_section->reloc_count;
1731 for (; rel < relend; rel++)
1733 int r_type;
1734 reloc_howto_type * howto;
1735 unsigned long r_symndx;
1736 Elf_Internal_Sym * sym;
1737 asection * sec;
1738 struct elf_link_hash_entry * h;
1739 bfd_vma relocation;
1740 bfd_reloc_status_type r;
1741 arelent bfd_reloc;
1743 r_symndx = ELF32_R_SYM (rel->r_info);
1744 r_type = ELF32_R_TYPE (rel->r_info);
1746 if ( r_type == R_ARM_GNU_VTENTRY
1747 || r_type == R_ARM_GNU_VTINHERIT)
1748 continue;
1750 elf32_arm_info_to_howto (input_bfd, & bfd_reloc, rel);
1751 howto = bfd_reloc.howto;
1753 if (info->relocateable)
1755 /* This is a relocateable link. We don't have to change
1756 anything, unless the reloc is against a section symbol,
1757 in which case we have to adjust according to where the
1758 section symbol winds up in the output section. */
1759 if (r_symndx < symtab_hdr->sh_info)
1761 sym = local_syms + r_symndx;
1762 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1764 sec = local_sections[r_symndx];
1765 #ifdef USE_REL
1766 arm_add_to_rel (input_bfd, contents + rel->r_offset,
1767 howto, sec->output_offset + sym->st_value);
1768 #else
1769 rel->r_addend += (sec->output_offset + sym->st_value)
1770 >> howto->rightshift;
1771 #endif
1775 continue;
1778 /* This is a final link. */
1779 h = NULL;
1780 sym = NULL;
1781 sec = NULL;
1783 if (r_symndx < symtab_hdr->sh_info)
1785 sym = local_syms + r_symndx;
1786 sec = local_sections[r_symndx];
1787 relocation = (sec->output_section->vma
1788 + sec->output_offset
1789 + sym->st_value);
1791 else
1793 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1795 while ( h->root.type == bfd_link_hash_indirect
1796 || h->root.type == bfd_link_hash_warning)
1797 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1799 if ( h->root.type == bfd_link_hash_defined
1800 || h->root.type == bfd_link_hash_defweak)
1802 int relocation_needed = 1;
1804 sec = h->root.u.def.section;
1806 /* In these cases, we don't need the relocation value.
1807 We check specially because in some obscure cases
1808 sec->output_section will be NULL. */
1809 switch (r_type)
1811 case R_ARM_PC24:
1812 case R_ARM_ABS32:
1813 if (info->shared
1814 && (
1815 (!info->symbolic && h->dynindx != -1)
1816 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1818 && ((input_section->flags & SEC_ALLOC) != 0
1819 /* DWARF will emit R_ARM_ABS32 relocations in its
1820 sections against symbols defined externally
1821 in shared libraries. We can't do anything
1822 with them here. */
1823 || ((input_section->flags & SEC_DEBUGGING) != 0
1824 && (h->elf_link_hash_flags
1825 & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
1827 relocation_needed = 0;
1828 break;
1830 case R_ARM_GOTPC:
1831 relocation_needed = 0;
1832 break;
1834 case R_ARM_GOT32:
1835 if (elf_hash_table(info)->dynamic_sections_created
1836 && (!info->shared
1837 || (!info->symbolic && h->dynindx != -1)
1838 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
1841 relocation_needed = 0;
1842 break;
1844 case R_ARM_PLT32:
1845 if (h->plt.offset != (bfd_vma)-1)
1846 relocation_needed = 0;
1847 break;
1849 default:
1850 if (sec->output_section == NULL)
1852 (*_bfd_error_handler)
1853 (_("%s: warning: unresolvable relocation against symbol `%s' from %s section"),
1854 bfd_get_filename (input_bfd), h->root.root.string,
1855 bfd_get_section_name (input_bfd, input_section));
1856 relocation_needed = 0;
1860 if (relocation_needed)
1861 relocation = h->root.u.def.value
1862 + sec->output_section->vma
1863 + sec->output_offset;
1864 else
1865 relocation = 0;
1867 else if (h->root.type == bfd_link_hash_undefweak)
1868 relocation = 0;
1869 else if (info->shared && !info->symbolic
1870 && !info->no_undefined
1871 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1872 relocation = 0;
1873 else
1875 if (!((*info->callbacks->undefined_symbol)
1876 (info, h->root.root.string, input_bfd,
1877 input_section, rel->r_offset,
1878 (!info->shared || info->no_undefined
1879 || ELF_ST_VISIBILITY (h->other)))))
1880 return false;
1881 relocation = 0;
1885 if (h != NULL)
1886 name = h->root.root.string;
1887 else
1889 name = (bfd_elf_string_from_elf_section
1890 (input_bfd, symtab_hdr->sh_link, sym->st_name));
1891 if (name == NULL || *name == '\0')
1892 name = bfd_section_name (input_bfd, sec);
1895 r = elf32_arm_final_link_relocate (howto, input_bfd, output_bfd,
1896 input_section, contents, rel,
1897 relocation, info, sec, name,
1898 (h ? ELF_ST_TYPE (h->type) :
1899 ELF_ST_TYPE (sym->st_info)), h);
1901 if (r != bfd_reloc_ok)
1903 const char * msg = (const char *) 0;
1905 switch (r)
1907 case bfd_reloc_overflow:
1908 /* If the overflowing reloc was to an undefined symbol,
1909 we have already printed one error message and there
1910 is no point complaining again. */
1911 if ((! h ||
1912 h->root.type != bfd_link_hash_undefined)
1913 && (!((*info->callbacks->reloc_overflow)
1914 (info, name, howto->name, (bfd_vma) 0,
1915 input_bfd, input_section, rel->r_offset))))
1916 return false;
1917 break;
1919 case bfd_reloc_undefined:
1920 if (!((*info->callbacks->undefined_symbol)
1921 (info, name, input_bfd, input_section,
1922 rel->r_offset, true)))
1923 return false;
1924 break;
1926 case bfd_reloc_outofrange:
1927 msg = _("internal error: out of range error");
1928 goto common_error;
1930 case bfd_reloc_notsupported:
1931 msg = _("internal error: unsupported relocation error");
1932 goto common_error;
1934 case bfd_reloc_dangerous:
1935 msg = _("internal error: dangerous error");
1936 goto common_error;
1938 default:
1939 msg = _("internal error: unknown error");
1940 /* fall through */
1942 common_error:
1943 if (!((*info->callbacks->warning)
1944 (info, msg, name, input_bfd, input_section,
1945 rel->r_offset)))
1946 return false;
1947 break;
1952 return true;
1955 /* Function to keep ARM specific flags in the ELF header. */
1956 static boolean
1957 elf32_arm_set_private_flags (abfd, flags)
1958 bfd *abfd;
1959 flagword flags;
1961 if (elf_flags_init (abfd)
1962 && elf_elfheader (abfd)->e_flags != flags)
1964 if (EF_ARM_EABI_VERSION (flags) == EF_ARM_EABI_UNKNOWN)
1966 if (flags & EF_INTERWORK)
1967 _bfd_error_handler (_("\
1968 Warning: Not setting interwork flag of %s since it has already been specified as non-interworking"),
1969 bfd_get_filename (abfd));
1970 else
1971 _bfd_error_handler (_("\
1972 Warning: Clearing the interwork flag of %s due to outside request"),
1973 bfd_get_filename (abfd));
1976 else
1978 elf_elfheader (abfd)->e_flags = flags;
1979 elf_flags_init (abfd) = true;
1982 return true;
1985 /* Copy backend specific data from one object module to another. */
1987 static boolean
1988 elf32_arm_copy_private_bfd_data (ibfd, obfd)
1989 bfd *ibfd;
1990 bfd *obfd;
1992 flagword in_flags;
1993 flagword out_flags;
1995 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
1996 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
1997 return true;
1999 in_flags = elf_elfheader (ibfd)->e_flags;
2000 out_flags = elf_elfheader (obfd)->e_flags;
2002 if (elf_flags_init (obfd)
2003 && EF_ARM_EABI_VERSION (out_flags) == EF_ARM_EABI_UNKNOWN
2004 && in_flags != out_flags)
2006 /* Cannot mix APCS26 and APCS32 code. */
2007 if ((in_flags & EF_APCS_26) != (out_flags & EF_APCS_26))
2008 return false;
2010 /* Cannot mix float APCS and non-float APCS code. */
2011 if ((in_flags & EF_APCS_FLOAT) != (out_flags & EF_APCS_FLOAT))
2012 return false;
2014 /* If the src and dest have different interworking flags
2015 then turn off the interworking bit. */
2016 if ((in_flags & EF_INTERWORK) != (out_flags & EF_INTERWORK))
2018 if (out_flags & EF_INTERWORK)
2019 _bfd_error_handler (_("\
2020 Warning: Clearing the interwork flag in %s because non-interworking code in %s has been linked with it"),
2021 bfd_get_filename (obfd), bfd_get_filename (ibfd));
2023 in_flags &= ~EF_INTERWORK;
2026 /* Likewise for PIC, though don't warn for this case. */
2027 if ((in_flags & EF_PIC) != (out_flags & EF_PIC))
2028 in_flags &= ~EF_PIC;
2031 elf_elfheader (obfd)->e_flags = in_flags;
2032 elf_flags_init (obfd) = true;
2034 return true;
2037 /* Merge backend specific data from an object file to the output
2038 object file when linking. */
2040 static boolean
2041 elf32_arm_merge_private_bfd_data (ibfd, obfd)
2042 bfd * ibfd;
2043 bfd * obfd;
2045 flagword out_flags;
2046 flagword in_flags;
2047 boolean flags_compatible = true;
2048 boolean null_input_bfd = true;
2049 asection *sec;
2051 /* Check if we have the same endianess. */
2052 if (_bfd_generic_verify_endian_match (ibfd, obfd) == false)
2053 return false;
2055 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
2056 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
2057 return true;
2059 /* The input BFD must have had its flags initialised. */
2060 /* The following seems bogus to me -- The flags are initialized in
2061 the assembler but I don't think an elf_flags_init field is
2062 written into the object. */
2063 /* BFD_ASSERT (elf_flags_init (ibfd)); */
2065 in_flags = elf_elfheader (ibfd)->e_flags;
2066 out_flags = elf_elfheader (obfd)->e_flags;
2068 if (!elf_flags_init (obfd))
2070 /* If the input is the default architecture and had the default
2071 flags then do not bother setting the flags for the output
2072 architecture, instead allow future merges to do this. If no
2073 future merges ever set these flags then they will retain their
2074 uninitialised values, which surprise surprise, correspond
2075 to the default values. */
2076 if (bfd_get_arch_info (ibfd)->the_default
2077 && elf_elfheader (ibfd)->e_flags == 0)
2078 return true;
2080 elf_flags_init (obfd) = true;
2081 elf_elfheader (obfd)->e_flags = in_flags;
2083 if (bfd_get_arch (obfd) == bfd_get_arch (ibfd)
2084 && bfd_get_arch_info (obfd)->the_default)
2085 return bfd_set_arch_mach (obfd, bfd_get_arch (ibfd), bfd_get_mach (ibfd));
2087 return true;
2090 /* Identical flags must be compatible. */
2091 if (in_flags == out_flags)
2092 return true;
2094 /* Check to see if the input BFD actually contains any sections.
2095 If not, its flags may not have been initialised either, but it cannot
2096 actually cause any incompatibility. */
2097 for (sec = ibfd->sections; sec != NULL; sec = sec->next)
2099 /* Ignore synthetic glue sections. */
2100 if (strcmp (sec->name, ".glue_7")
2101 && strcmp (sec->name, ".glue_7t"))
2103 null_input_bfd = false;
2104 break;
2107 if (null_input_bfd)
2108 return true;
2110 /* Complain about various flag mismatches. */
2111 if (EF_ARM_EABI_VERSION (in_flags) != EF_ARM_EABI_VERSION (out_flags))
2113 _bfd_error_handler (_("\
2114 Error: %s compiled for EABI version %d, whereas %s is compiled for version %d"),
2115 bfd_get_filename (ibfd),
2116 (in_flags & EF_ARM_EABIMASK) >> 24,
2117 bfd_get_filename (obfd),
2118 (out_flags & EF_ARM_EABIMASK) >> 24);
2119 return false;
2122 /* Not sure what needs to be checked for EABI versions >= 1. */
2123 if (EF_ARM_EABI_VERSION (in_flags) == EF_ARM_EABI_UNKNOWN)
2125 if ((in_flags & EF_APCS_26) != (out_flags & EF_APCS_26))
2127 _bfd_error_handler (_("\
2128 Error: %s compiled for APCS-%d, whereas %s is compiled for APCS-%d"),
2129 bfd_get_filename (ibfd),
2130 in_flags & EF_APCS_26 ? 26 : 32,
2131 bfd_get_filename (obfd),
2132 out_flags & EF_APCS_26 ? 26 : 32);
2133 flags_compatible = false;
2136 if ((in_flags & EF_APCS_FLOAT) != (out_flags & EF_APCS_FLOAT))
2138 _bfd_error_handler (_("\
2139 Error: %s passes floats in %s registers, whereas %s passes them in %s registers"),
2140 bfd_get_filename (ibfd),
2141 in_flags & EF_APCS_FLOAT ? _("float") : _("integer"),
2142 bfd_get_filename (obfd),
2143 out_flags & EF_APCS_26 ? _("float") : _("integer"));
2144 flags_compatible = false;
2147 #ifdef EF_SOFT_FLOAT
2148 if ((in_flags & EF_SOFT_FLOAT) != (out_flags & EF_SOFT_FLOAT))
2150 _bfd_error_handler (_ ("\
2151 Error: %s uses %s floating point, whereas %s uses %s floating point"),
2152 bfd_get_filename (ibfd),
2153 in_flags & EF_SOFT_FLOAT ? _("soft") : _("hard"),
2154 bfd_get_filename (obfd),
2155 out_flags & EF_SOFT_FLOAT ? _("soft") : _("hard"));
2156 flags_compatible = false;
2158 #endif
2160 /* Interworking mismatch is only a warning. */
2161 if ((in_flags & EF_INTERWORK) != (out_flags & EF_INTERWORK))
2162 _bfd_error_handler (_("\
2163 Warning: %s %s interworking, whereas %s %s"),
2164 bfd_get_filename (ibfd),
2165 in_flags & EF_INTERWORK ? _("supports") : _("does not support"),
2166 bfd_get_filename (obfd),
2167 out_flags & EF_INTERWORK ? _("does not") : _("does"));
2170 return flags_compatible;
2173 /* Display the flags field. */
2175 static boolean
2176 elf32_arm_print_private_bfd_data (abfd, ptr)
2177 bfd *abfd;
2178 PTR ptr;
2180 FILE * file = (FILE *) ptr;
2181 unsigned long flags;
2183 BFD_ASSERT (abfd != NULL && ptr != NULL);
2185 /* Print normal ELF private data. */
2186 _bfd_elf_print_private_bfd_data (abfd, ptr);
2188 flags = elf_elfheader (abfd)->e_flags;
2189 /* Ignore init flag - it may not be set, despite the flags field
2190 containing valid data. */
2192 /* xgettext:c-format */
2193 fprintf (file, _("private flags = %lx:"), elf_elfheader (abfd)->e_flags);
2195 switch (EF_ARM_EABI_VERSION (flags))
2197 case EF_ARM_EABI_UNKNOWN:
2198 /* The following flag bits are GNU extenstions and not part of the
2199 official ARM ELF extended ABI. Hence they are only decoded if
2200 the EABI version is not set. */
2201 if (flags & EF_INTERWORK)
2202 fprintf (file, _(" [interworking enabled]"));
2204 if (flags & EF_APCS_26)
2205 fprintf (file, _(" [APCS-26]"));
2206 else
2207 fprintf (file, _(" [APCS-32]"));
2209 if (flags & EF_APCS_FLOAT)
2210 fprintf (file, _(" [floats passed in float registers]"));
2212 if (flags & EF_PIC)
2213 fprintf (file, _(" [position independent]"));
2215 if (flags & EF_NEW_ABI)
2216 fprintf (file, _(" [new ABI]"));
2218 if (flags & EF_OLD_ABI)
2219 fprintf (file, _(" [old ABI]"));
2221 if (flags & EF_SOFT_FLOAT)
2222 fprintf (file, _(" [software FP]"));
2224 flags &= ~(EF_INTERWORK | EF_APCS_26 | EF_APCS_FLOAT | EF_PIC
2225 | EF_NEW_ABI | EF_OLD_ABI | EF_SOFT_FLOAT);
2226 break;
2228 case EF_ARM_EABI_VER1:
2229 fprintf (file, _(" [Version1 EABI]"));
2231 if (flags & EF_ARM_SYMSARESORTED)
2232 fprintf (file, _(" [sorted symbol table]"));
2233 else
2234 fprintf (file, _(" [unsorted symbol table]"));
2236 flags &= ~ EF_ARM_SYMSARESORTED;
2237 break;
2239 default:
2240 fprintf (file, _(" <EABI version unrecognised>"));
2241 break;
2244 flags &= ~ EF_ARM_EABIMASK;
2246 if (flags & EF_ARM_RELEXEC)
2247 fprintf (file, _(" [relocatable executable]"));
2249 if (flags & EF_ARM_HASENTRY)
2250 fprintf (file, _(" [has entry point]"));
2252 flags &= ~ (EF_ARM_RELEXEC | EF_ARM_HASENTRY);
2254 if (flags)
2255 fprintf (file, _("<Unrecognised flag bits set>"));
2257 fputc ('\n', file);
2259 return true;
2262 static int
2263 elf32_arm_get_symbol_type (elf_sym, type)
2264 Elf_Internal_Sym * elf_sym;
2265 int type;
2267 switch (ELF_ST_TYPE (elf_sym->st_info))
2269 case STT_ARM_TFUNC:
2270 return ELF_ST_TYPE (elf_sym->st_info);
2272 case STT_ARM_16BIT:
2273 /* If the symbol is not an object, return the STT_ARM_16BIT flag.
2274 This allows us to distinguish between data used by Thumb instructions
2275 and non-data (which is probably code) inside Thumb regions of an
2276 executable. */
2277 if (type != STT_OBJECT)
2278 return ELF_ST_TYPE (elf_sym->st_info);
2279 break;
2281 default:
2282 break;
2285 return type;
2288 static asection *
2289 elf32_arm_gc_mark_hook (abfd, info, rel, h, sym)
2290 bfd *abfd;
2291 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2292 Elf_Internal_Rela *rel;
2293 struct elf_link_hash_entry *h;
2294 Elf_Internal_Sym *sym;
2296 if (h != NULL)
2298 switch (ELF32_R_TYPE (rel->r_info))
2300 case R_ARM_GNU_VTINHERIT:
2301 case R_ARM_GNU_VTENTRY:
2302 break;
2304 default:
2305 switch (h->root.type)
2307 case bfd_link_hash_defined:
2308 case bfd_link_hash_defweak:
2309 return h->root.u.def.section;
2311 case bfd_link_hash_common:
2312 return h->root.u.c.p->section;
2314 default:
2315 break;
2319 else
2321 if (!(elf_bad_symtab (abfd)
2322 && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
2323 && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
2324 && sym->st_shndx != SHN_COMMON))
2326 return bfd_section_from_elf_index (abfd, sym->st_shndx);
2329 return NULL;
2332 /* Update the got entry reference counts for the section being removed. */
2334 static boolean
2335 elf32_arm_gc_sweep_hook (abfd, info, sec, relocs)
2336 bfd *abfd ATTRIBUTE_UNUSED;
2337 struct bfd_link_info *info ATTRIBUTE_UNUSED;
2338 asection *sec ATTRIBUTE_UNUSED;
2339 const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
2341 /* We don't support garbage collection of GOT and PLT relocs yet. */
2342 return true;
2345 /* Look through the relocs for a section during the first phase. */
2347 static boolean
2348 elf32_arm_check_relocs (abfd, info, sec, relocs)
2349 bfd * abfd;
2350 struct bfd_link_info * info;
2351 asection * sec;
2352 const Elf_Internal_Rela * relocs;
2354 Elf_Internal_Shdr * symtab_hdr;
2355 struct elf_link_hash_entry ** sym_hashes;
2356 struct elf_link_hash_entry ** sym_hashes_end;
2357 const Elf_Internal_Rela * rel;
2358 const Elf_Internal_Rela * rel_end;
2359 bfd * dynobj;
2360 asection * sgot, *srelgot, *sreloc;
2361 bfd_vma * local_got_offsets;
2363 if (info->relocateable)
2364 return true;
2366 sgot = srelgot = sreloc = NULL;
2368 dynobj = elf_hash_table (info)->dynobj;
2369 local_got_offsets = elf_local_got_offsets (abfd);
2371 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2372 sym_hashes = elf_sym_hashes (abfd);
2373 sym_hashes_end = sym_hashes
2374 + symtab_hdr->sh_size / sizeof (Elf32_External_Sym);
2376 if (!elf_bad_symtab (abfd))
2377 sym_hashes_end -= symtab_hdr->sh_info;
2379 rel_end = relocs + sec->reloc_count;
2380 for (rel = relocs; rel < rel_end; rel++)
2382 struct elf_link_hash_entry *h;
2383 unsigned long r_symndx;
2385 r_symndx = ELF32_R_SYM (rel->r_info);
2386 if (r_symndx < symtab_hdr->sh_info)
2387 h = NULL;
2388 else
2389 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
2391 /* Some relocs require a global offset table. */
2392 if (dynobj == NULL)
2394 switch (ELF32_R_TYPE (rel->r_info))
2396 case R_ARM_GOT32:
2397 case R_ARM_GOTOFF:
2398 case R_ARM_GOTPC:
2399 elf_hash_table (info)->dynobj = dynobj = abfd;
2400 if (! _bfd_elf_create_got_section (dynobj, info))
2401 return false;
2402 break;
2404 default:
2405 break;
2409 switch (ELF32_R_TYPE (rel->r_info))
2411 case R_ARM_GOT32:
2412 /* This symbol requires a global offset table entry. */
2413 if (sgot == NULL)
2415 sgot = bfd_get_section_by_name (dynobj, ".got");
2416 BFD_ASSERT (sgot != NULL);
2419 /* Get the got relocation section if necessary. */
2420 if (srelgot == NULL
2421 && (h != NULL || info->shared))
2423 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
2425 /* If no got relocation section, make one and initialize. */
2426 if (srelgot == NULL)
2428 srelgot = bfd_make_section (dynobj, ".rel.got");
2429 if (srelgot == NULL
2430 || ! bfd_set_section_flags (dynobj, srelgot,
2431 (SEC_ALLOC
2432 | SEC_LOAD
2433 | SEC_HAS_CONTENTS
2434 | SEC_IN_MEMORY
2435 | SEC_LINKER_CREATED
2436 | SEC_READONLY))
2437 || ! bfd_set_section_alignment (dynobj, srelgot, 2))
2438 return false;
2442 if (h != NULL)
2444 if (h->got.offset != (bfd_vma) -1)
2445 /* We have already allocated space in the .got. */
2446 break;
2448 h->got.offset = sgot->_raw_size;
2450 /* Make sure this symbol is output as a dynamic symbol. */
2451 if (h->dynindx == -1)
2452 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2453 return false;
2455 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2457 else
2459 /* This is a global offset table entry for a local
2460 symbol. */
2461 if (local_got_offsets == NULL)
2463 size_t size;
2464 register unsigned int i;
2466 size = symtab_hdr->sh_info * sizeof (bfd_vma);
2467 local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
2468 if (local_got_offsets == NULL)
2469 return false;
2470 elf_local_got_offsets (abfd) = local_got_offsets;
2471 for (i = 0; i < symtab_hdr->sh_info; i++)
2472 local_got_offsets[i] = (bfd_vma) -1;
2475 if (local_got_offsets[r_symndx] != (bfd_vma) -1)
2476 /* We have already allocated space in the .got. */
2477 break;
2479 local_got_offsets[r_symndx] = sgot->_raw_size;
2481 if (info->shared)
2482 /* If we are generating a shared object, we need to
2483 output a R_ARM_RELATIVE reloc so that the dynamic
2484 linker can adjust this GOT entry. */
2485 srelgot->_raw_size += sizeof (Elf32_External_Rel);
2488 sgot->_raw_size += 4;
2489 break;
2491 case R_ARM_PLT32:
2492 /* This symbol requires a procedure linkage table entry. We
2493 actually build the entry in adjust_dynamic_symbol,
2494 because this might be a case of linking PIC code which is
2495 never referenced by a dynamic object, in which case we
2496 don't need to generate a procedure linkage table entry
2497 after all. */
2499 /* If this is a local symbol, we resolve it directly without
2500 creating a procedure linkage table entry. */
2501 if (h == NULL)
2502 continue;
2504 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
2505 break;
2507 case R_ARM_ABS32:
2508 case R_ARM_REL32:
2509 case R_ARM_PC24:
2510 /* If we are creating a shared library, and this is a reloc
2511 against a global symbol, or a non PC relative reloc
2512 against a local symbol, then we need to copy the reloc
2513 into the shared library. However, if we are linking with
2514 -Bsymbolic, we do not need to copy a reloc against a
2515 global symbol which is defined in an object we are
2516 including in the link (i.e., DEF_REGULAR is set). At
2517 this point we have not seen all the input files, so it is
2518 possible that DEF_REGULAR is not set now but will be set
2519 later (it is never cleared). We account for that
2520 possibility below by storing information in the
2521 pcrel_relocs_copied field of the hash table entry. */
2522 if (info->shared
2523 && (ELF32_R_TYPE (rel->r_info) != R_ARM_PC24
2524 || (h != NULL
2525 && (! info->symbolic
2526 || (h->elf_link_hash_flags
2527 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
2529 /* When creating a shared object, we must copy these
2530 reloc types into the output file. We create a reloc
2531 section in dynobj and make room for this reloc. */
2532 if (sreloc == NULL)
2534 const char * name;
2536 name = (bfd_elf_string_from_elf_section
2537 (abfd,
2538 elf_elfheader (abfd)->e_shstrndx,
2539 elf_section_data (sec)->rel_hdr.sh_name));
2540 if (name == NULL)
2541 return false;
2543 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
2544 && strcmp (bfd_get_section_name (abfd, sec),
2545 name + 4) == 0);
2547 sreloc = bfd_get_section_by_name (dynobj, name);
2548 if (sreloc == NULL)
2550 flagword flags;
2552 sreloc = bfd_make_section (dynobj, name);
2553 flags = (SEC_HAS_CONTENTS | SEC_READONLY
2554 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2555 if ((sec->flags & SEC_ALLOC) != 0)
2556 flags |= SEC_ALLOC | SEC_LOAD;
2557 if (sreloc == NULL
2558 || ! bfd_set_section_flags (dynobj, sreloc, flags)
2559 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
2560 return false;
2564 sreloc->_raw_size += sizeof (Elf32_External_Rel);
2565 /* If we are linking with -Bsymbolic, and this is a
2566 global symbol, we count the number of PC relative
2567 relocations we have entered for this symbol, so that
2568 we can discard them again if the symbol is later
2569 defined by a regular object. Note that this function
2570 is only called if we are using an elf_i386 linker
2571 hash table, which means that h is really a pointer to
2572 an elf_i386_link_hash_entry. */
2573 if (h != NULL && info->symbolic
2574 && ELF32_R_TYPE (rel->r_info) == R_ARM_PC24)
2576 struct elf32_arm_link_hash_entry * eh;
2577 struct elf32_arm_pcrel_relocs_copied * p;
2579 eh = (struct elf32_arm_link_hash_entry *) h;
2581 for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
2582 if (p->section == sreloc)
2583 break;
2585 if (p == NULL)
2587 p = ((struct elf32_arm_pcrel_relocs_copied *)
2588 bfd_alloc (dynobj, sizeof * p));
2590 if (p == NULL)
2591 return false;
2592 p->next = eh->pcrel_relocs_copied;
2593 eh->pcrel_relocs_copied = p;
2594 p->section = sreloc;
2595 p->count = 0;
2598 ++p->count;
2601 break;
2603 /* This relocation describes the C++ object vtable hierarchy.
2604 Reconstruct it for later use during GC. */
2605 case R_ARM_GNU_VTINHERIT:
2606 if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
2607 return false;
2608 break;
2610 /* This relocation describes which C++ vtable entries are actually
2611 used. Record for later use during GC. */
2612 case R_ARM_GNU_VTENTRY:
2613 if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_offset))
2614 return false;
2615 break;
2619 return true;
2622 /* Find the nearest line to a particular section and offset, for error
2623 reporting. This code is a duplicate of the code in elf.c, except
2624 that it also accepts STT_ARM_TFUNC as a symbol that names a function. */
2626 static boolean
2627 elf32_arm_find_nearest_line
2628 (abfd, section, symbols, offset, filename_ptr, functionname_ptr, line_ptr)
2629 bfd * abfd;
2630 asection * section;
2631 asymbol ** symbols;
2632 bfd_vma offset;
2633 CONST char ** filename_ptr;
2634 CONST char ** functionname_ptr;
2635 unsigned int * line_ptr;
2637 boolean found;
2638 const char * filename;
2639 asymbol * func;
2640 bfd_vma low_func;
2641 asymbol ** p;
2643 if (_bfd_dwarf2_find_nearest_line (abfd, section, symbols, offset,
2644 filename_ptr, functionname_ptr,
2645 line_ptr, 0,
2646 &elf_tdata (abfd)->dwarf2_find_line_info))
2647 return true;
2649 if (! _bfd_stab_section_find_nearest_line (abfd, symbols, section, offset,
2650 &found, filename_ptr,
2651 functionname_ptr, line_ptr,
2652 &elf_tdata (abfd)->line_info))
2653 return false;
2655 if (found)
2656 return true;
2658 if (symbols == NULL)
2659 return false;
2661 filename = NULL;
2662 func = NULL;
2663 low_func = 0;
2665 for (p = symbols; *p != NULL; p++)
2667 elf_symbol_type *q;
2669 q = (elf_symbol_type *) *p;
2671 if (bfd_get_section (&q->symbol) != section)
2672 continue;
2674 switch (ELF_ST_TYPE (q->internal_elf_sym.st_info))
2676 default:
2677 break;
2678 case STT_FILE:
2679 filename = bfd_asymbol_name (&q->symbol);
2680 break;
2681 case STT_NOTYPE:
2682 case STT_FUNC:
2683 case STT_ARM_TFUNC:
2684 if (q->symbol.section == section
2685 && q->symbol.value >= low_func
2686 && q->symbol.value <= offset)
2688 func = (asymbol *) q;
2689 low_func = q->symbol.value;
2691 break;
2695 if (func == NULL)
2696 return false;
2698 *filename_ptr = filename;
2699 *functionname_ptr = bfd_asymbol_name (func);
2700 *line_ptr = 0;
2702 return true;
2705 /* Adjust a symbol defined by a dynamic object and referenced by a
2706 regular object. The current definition is in some section of the
2707 dynamic object, but we're not including those sections. We have to
2708 change the definition to something the rest of the link can
2709 understand. */
2711 static boolean
2712 elf32_arm_adjust_dynamic_symbol (info, h)
2713 struct bfd_link_info * info;
2714 struct elf_link_hash_entry * h;
2716 bfd * dynobj;
2717 asection * s;
2718 unsigned int power_of_two;
2720 dynobj = elf_hash_table (info)->dynobj;
2722 /* Make sure we know what is going on here. */
2723 BFD_ASSERT (dynobj != NULL
2724 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
2725 || h->weakdef != NULL
2726 || ((h->elf_link_hash_flags
2727 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2728 && (h->elf_link_hash_flags
2729 & ELF_LINK_HASH_REF_REGULAR) != 0
2730 && (h->elf_link_hash_flags
2731 & ELF_LINK_HASH_DEF_REGULAR) == 0)));
2733 /* If this is a function, put it in the procedure linkage table. We
2734 will fill in the contents of the procedure linkage table later,
2735 when we know the address of the .got section. */
2736 if (h->type == STT_FUNC
2737 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
2739 if (! info->shared
2740 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2741 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
2743 /* This case can occur if we saw a PLT32 reloc in an input
2744 file, but the symbol was never referred to by a dynamic
2745 object. In such a case, we don't actually need to build
2746 a procedure linkage table, and we can just do a PC32
2747 reloc instead. */
2748 BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
2749 return true;
2752 /* Make sure this symbol is output as a dynamic symbol. */
2753 if (h->dynindx == -1)
2755 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
2756 return false;
2759 s = bfd_get_section_by_name (dynobj, ".plt");
2760 BFD_ASSERT (s != NULL);
2762 /* If this is the first .plt entry, make room for the special
2763 first entry. */
2764 if (s->_raw_size == 0)
2765 s->_raw_size += PLT_ENTRY_SIZE;
2767 /* If this symbol is not defined in a regular file, and we are
2768 not generating a shared library, then set the symbol to this
2769 location in the .plt. This is required to make function
2770 pointers compare as equal between the normal executable and
2771 the shared library. */
2772 if (! info->shared
2773 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2775 h->root.u.def.section = s;
2776 h->root.u.def.value = s->_raw_size;
2779 h->plt.offset = s->_raw_size;
2781 /* Make room for this entry. */
2782 s->_raw_size += PLT_ENTRY_SIZE;
2784 /* We also need to make an entry in the .got.plt section, which
2785 will be placed in the .got section by the linker script. */
2786 s = bfd_get_section_by_name (dynobj, ".got.plt");
2787 BFD_ASSERT (s != NULL);
2788 s->_raw_size += 4;
2790 /* We also need to make an entry in the .rel.plt section. */
2792 s = bfd_get_section_by_name (dynobj, ".rel.plt");
2793 BFD_ASSERT (s != NULL);
2794 s->_raw_size += sizeof (Elf32_External_Rel);
2796 return true;
2799 /* If this is a weak symbol, and there is a real definition, the
2800 processor independent code will have arranged for us to see the
2801 real definition first, and we can just use the same value. */
2802 if (h->weakdef != NULL)
2804 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
2805 || h->weakdef->root.type == bfd_link_hash_defweak);
2806 h->root.u.def.section = h->weakdef->root.u.def.section;
2807 h->root.u.def.value = h->weakdef->root.u.def.value;
2808 return true;
2811 /* This is a reference to a symbol defined by a dynamic object which
2812 is not a function. */
2814 /* If we are creating a shared library, we must presume that the
2815 only references to the symbol are via the global offset table.
2816 For such cases we need not do anything here; the relocations will
2817 be handled correctly by relocate_section. */
2818 if (info->shared)
2819 return true;
2821 /* We must allocate the symbol in our .dynbss section, which will
2822 become part of the .bss section of the executable. There will be
2823 an entry for this symbol in the .dynsym section. The dynamic
2824 object will contain position independent code, so all references
2825 from the dynamic object to this symbol will go through the global
2826 offset table. The dynamic linker will use the .dynsym entry to
2827 determine the address it must put in the global offset table, so
2828 both the dynamic object and the regular object will refer to the
2829 same memory location for the variable. */
2830 s = bfd_get_section_by_name (dynobj, ".dynbss");
2831 BFD_ASSERT (s != NULL);
2833 /* We must generate a R_ARM_COPY reloc to tell the dynamic linker to
2834 copy the initial value out of the dynamic object and into the
2835 runtime process image. We need to remember the offset into the
2836 .rel.bss section we are going to use. */
2837 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
2839 asection *srel;
2841 srel = bfd_get_section_by_name (dynobj, ".rel.bss");
2842 BFD_ASSERT (srel != NULL);
2843 srel->_raw_size += sizeof (Elf32_External_Rel);
2844 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
2847 /* We need to figure out the alignment required for this symbol. I
2848 have no idea how ELF linkers handle this. */
2849 power_of_two = bfd_log2 (h->size);
2850 if (power_of_two > 3)
2851 power_of_two = 3;
2853 /* Apply the required alignment. */
2854 s->_raw_size = BFD_ALIGN (s->_raw_size,
2855 (bfd_size_type) (1 << power_of_two));
2856 if (power_of_two > bfd_get_section_alignment (dynobj, s))
2858 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
2859 return false;
2862 /* Define the symbol as being at this point in the section. */
2863 h->root.u.def.section = s;
2864 h->root.u.def.value = s->_raw_size;
2866 /* Increment the section size to make room for the symbol. */
2867 s->_raw_size += h->size;
2869 return true;
2872 /* Set the sizes of the dynamic sections. */
2874 static boolean
2875 elf32_arm_size_dynamic_sections (output_bfd, info)
2876 bfd * output_bfd;
2877 struct bfd_link_info * info;
2879 bfd * dynobj;
2880 asection * s;
2881 boolean plt;
2882 boolean relocs;
2883 boolean reltext;
2885 dynobj = elf_hash_table (info)->dynobj;
2886 BFD_ASSERT (dynobj != NULL);
2888 if (elf_hash_table (info)->dynamic_sections_created)
2890 /* Set the contents of the .interp section to the interpreter. */
2891 if (! info->shared)
2893 s = bfd_get_section_by_name (dynobj, ".interp");
2894 BFD_ASSERT (s != NULL);
2895 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
2896 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
2899 else
2901 /* We may have created entries in the .rel.got section.
2902 However, if we are not creating the dynamic sections, we will
2903 not actually use these entries. Reset the size of .rel.got,
2904 which will cause it to get stripped from the output file
2905 below. */
2906 s = bfd_get_section_by_name (dynobj, ".rel.got");
2907 if (s != NULL)
2908 s->_raw_size = 0;
2911 /* If this is a -Bsymbolic shared link, then we need to discard all
2912 PC relative relocs against symbols defined in a regular object.
2913 We allocated space for them in the check_relocs routine, but we
2914 will not fill them in in the relocate_section routine. */
2915 if (info->shared && info->symbolic)
2916 elf32_arm_link_hash_traverse (elf32_arm_hash_table (info),
2917 elf32_arm_discard_copies,
2918 (PTR) NULL);
2920 /* The check_relocs and adjust_dynamic_symbol entry points have
2921 determined the sizes of the various dynamic sections. Allocate
2922 memory for them. */
2923 plt = false;
2924 relocs = false;
2925 reltext = false;
2926 for (s = dynobj->sections; s != NULL; s = s->next)
2928 const char * name;
2929 boolean strip;
2931 if ((s->flags & SEC_LINKER_CREATED) == 0)
2932 continue;
2934 /* It's OK to base decisions on the section name, because none
2935 of the dynobj section names depend upon the input files. */
2936 name = bfd_get_section_name (dynobj, s);
2938 strip = false;
2940 if (strcmp (name, ".plt") == 0)
2942 if (s->_raw_size == 0)
2944 /* Strip this section if we don't need it; see the
2945 comment below. */
2946 strip = true;
2948 else
2950 /* Remember whether there is a PLT. */
2951 plt = true;
2954 else if (strncmp (name, ".rel", 4) == 0)
2956 if (s->_raw_size == 0)
2958 /* If we don't need this section, strip it from the
2959 output file. This is mostly to handle .rel.bss and
2960 .rel.plt. We must create both sections in
2961 create_dynamic_sections, because they must be created
2962 before the linker maps input sections to output
2963 sections. The linker does that before
2964 adjust_dynamic_symbol is called, and it is that
2965 function which decides whether anything needs to go
2966 into these sections. */
2967 strip = true;
2969 else
2971 asection * target;
2973 /* Remember whether there are any reloc sections other
2974 than .rel.plt. */
2975 if (strcmp (name, ".rel.plt") != 0)
2977 const char *outname;
2979 relocs = true;
2981 /* If this relocation section applies to a read only
2982 section, then we probably need a DT_TEXTREL
2983 entry. The entries in the .rel.plt section
2984 really apply to the .got section, which we
2985 created ourselves and so know is not readonly. */
2986 outname = bfd_get_section_name (output_bfd,
2987 s->output_section);
2988 target = bfd_get_section_by_name (output_bfd, outname + 4);
2990 if (target != NULL
2991 && (target->flags & SEC_READONLY) != 0
2992 && (target->flags & SEC_ALLOC) != 0)
2993 reltext = true;
2996 /* We use the reloc_count field as a counter if we need
2997 to copy relocs into the output file. */
2998 s->reloc_count = 0;
3001 else if (strncmp (name, ".got", 4) != 0)
3003 /* It's not one of our sections, so don't allocate space. */
3004 continue;
3007 if (strip)
3009 asection ** spp;
3011 for (spp = &s->output_section->owner->sections;
3012 *spp != s->output_section;
3013 spp = &(*spp)->next)
3015 *spp = s->output_section->next;
3016 --s->output_section->owner->section_count;
3018 continue;
3021 /* Allocate memory for the section contents. */
3022 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
3023 if (s->contents == NULL && s->_raw_size != 0)
3024 return false;
3027 if (elf_hash_table (info)->dynamic_sections_created)
3029 /* Add some entries to the .dynamic section. We fill in the
3030 values later, in elf32_arm_finish_dynamic_sections, but we
3031 must add the entries now so that we get the correct size for
3032 the .dynamic section. The DT_DEBUG entry is filled in by the
3033 dynamic linker and used by the debugger. */
3034 if (! info->shared)
3036 if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
3037 return false;
3040 if (plt)
3042 if ( ! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
3043 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
3044 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
3045 || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
3046 return false;
3049 if (relocs)
3051 if ( ! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
3052 || ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
3053 || ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
3054 sizeof (Elf32_External_Rel)))
3055 return false;
3058 if (reltext)
3060 if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
3061 return false;
3062 info->flags |= DF_TEXTREL;
3066 return true;
3069 /* This function is called via elf32_arm_link_hash_traverse if we are
3070 creating a shared object with -Bsymbolic. It discards the space
3071 allocated to copy PC relative relocs against symbols which are
3072 defined in regular objects. We allocated space for them in the
3073 check_relocs routine, but we won't fill them in in the
3074 relocate_section routine. */
3076 static boolean
3077 elf32_arm_discard_copies (h, ignore)
3078 struct elf32_arm_link_hash_entry * h;
3079 PTR ignore ATTRIBUTE_UNUSED;
3081 struct elf32_arm_pcrel_relocs_copied * s;
3083 /* We only discard relocs for symbols defined in a regular object. */
3084 if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3085 return true;
3087 for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
3088 s->section->_raw_size -= s->count * sizeof (Elf32_External_Rel);
3090 return true;
3093 /* Finish up dynamic symbol handling. We set the contents of various
3094 dynamic sections here. */
3096 static boolean
3097 elf32_arm_finish_dynamic_symbol (output_bfd, info, h, sym)
3098 bfd * output_bfd;
3099 struct bfd_link_info * info;
3100 struct elf_link_hash_entry * h;
3101 Elf_Internal_Sym * sym;
3103 bfd * dynobj;
3105 dynobj = elf_hash_table (info)->dynobj;
3107 if (h->plt.offset != (bfd_vma) -1)
3109 asection * splt;
3110 asection * sgot;
3111 asection * srel;
3112 bfd_vma plt_index;
3113 bfd_vma got_offset;
3114 Elf_Internal_Rel rel;
3116 /* This symbol has an entry in the procedure linkage table. Set
3117 it up. */
3119 BFD_ASSERT (h->dynindx != -1);
3121 splt = bfd_get_section_by_name (dynobj, ".plt");
3122 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
3123 srel = bfd_get_section_by_name (dynobj, ".rel.plt");
3124 BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
3126 /* Get the index in the procedure linkage table which
3127 corresponds to this symbol. This is the index of this symbol
3128 in all the symbols for which we are making plt entries. The
3129 first entry in the procedure linkage table is reserved. */
3130 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
3132 /* Get the offset into the .got table of the entry that
3133 corresponds to this function. Each .got entry is 4 bytes.
3134 The first three are reserved. */
3135 got_offset = (plt_index + 3) * 4;
3137 /* Fill in the entry in the procedure linkage table. */
3138 memcpy (splt->contents + h->plt.offset,
3139 elf32_arm_plt_entry,
3140 PLT_ENTRY_SIZE);
3141 bfd_put_32 (output_bfd,
3142 (sgot->output_section->vma
3143 + sgot->output_offset
3144 + got_offset
3145 - splt->output_section->vma
3146 - splt->output_offset
3147 - h->plt.offset - 12),
3148 splt->contents + h->plt.offset + 12);
3150 /* Fill in the entry in the global offset table. */
3151 bfd_put_32 (output_bfd,
3152 (splt->output_section->vma
3153 + splt->output_offset),
3154 sgot->contents + got_offset);
3156 /* Fill in the entry in the .rel.plt section. */
3157 rel.r_offset = (sgot->output_section->vma
3158 + sgot->output_offset
3159 + got_offset);
3160 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_JUMP_SLOT);
3161 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3162 ((Elf32_External_Rel *) srel->contents
3163 + plt_index));
3165 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3167 /* Mark the symbol as undefined, rather than as defined in
3168 the .plt section. Leave the value alone. */
3169 sym->st_shndx = SHN_UNDEF;
3173 if (h->got.offset != (bfd_vma) -1)
3175 asection * sgot;
3176 asection * srel;
3177 Elf_Internal_Rel rel;
3179 /* This symbol has an entry in the global offset table. Set it
3180 up. */
3181 sgot = bfd_get_section_by_name (dynobj, ".got");
3182 srel = bfd_get_section_by_name (dynobj, ".rel.got");
3183 BFD_ASSERT (sgot != NULL && srel != NULL);
3185 rel.r_offset = (sgot->output_section->vma
3186 + sgot->output_offset
3187 + (h->got.offset &~ 1));
3189 /* If this is a -Bsymbolic link, and the symbol is defined
3190 locally, we just want to emit a RELATIVE reloc. The entry in
3191 the global offset table will already have been initialized in
3192 the relocate_section function. */
3193 if (info->shared
3194 && (info->symbolic || h->dynindx == -1)
3195 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
3196 rel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE);
3197 else
3199 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got.offset);
3200 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_GLOB_DAT);
3203 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3204 ((Elf32_External_Rel *) srel->contents
3205 + srel->reloc_count));
3206 ++srel->reloc_count;
3209 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
3211 asection * s;
3212 Elf_Internal_Rel rel;
3214 /* This symbol needs a copy reloc. Set it up. */
3215 BFD_ASSERT (h->dynindx != -1
3216 && (h->root.type == bfd_link_hash_defined
3217 || h->root.type == bfd_link_hash_defweak));
3219 s = bfd_get_section_by_name (h->root.u.def.section->owner,
3220 ".rel.bss");
3221 BFD_ASSERT (s != NULL);
3223 rel.r_offset = (h->root.u.def.value
3224 + h->root.u.def.section->output_section->vma
3225 + h->root.u.def.section->output_offset);
3226 rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_COPY);
3227 bfd_elf32_swap_reloc_out (output_bfd, &rel,
3228 ((Elf32_External_Rel *) s->contents
3229 + s->reloc_count));
3230 ++s->reloc_count;
3233 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3234 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3235 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
3236 sym->st_shndx = SHN_ABS;
3238 return true;
3241 /* Finish up the dynamic sections. */
3243 static boolean
3244 elf32_arm_finish_dynamic_sections (output_bfd, info)
3245 bfd * output_bfd;
3246 struct bfd_link_info * info;
3248 bfd * dynobj;
3249 asection * sgot;
3250 asection * sdyn;
3252 dynobj = elf_hash_table (info)->dynobj;
3254 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
3255 BFD_ASSERT (sgot != NULL);
3256 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3258 if (elf_hash_table (info)->dynamic_sections_created)
3260 asection *splt;
3261 Elf32_External_Dyn *dyncon, *dynconend;
3263 splt = bfd_get_section_by_name (dynobj, ".plt");
3264 BFD_ASSERT (splt != NULL && sdyn != NULL);
3266 dyncon = (Elf32_External_Dyn *) sdyn->contents;
3267 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
3269 for (; dyncon < dynconend; dyncon++)
3271 Elf_Internal_Dyn dyn;
3272 const char * name;
3273 asection * s;
3275 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
3277 switch (dyn.d_tag)
3279 default:
3280 break;
3282 case DT_PLTGOT:
3283 name = ".got";
3284 goto get_vma;
3285 case DT_JMPREL:
3286 name = ".rel.plt";
3287 get_vma:
3288 s = bfd_get_section_by_name (output_bfd, name);
3289 BFD_ASSERT (s != NULL);
3290 dyn.d_un.d_ptr = s->vma;
3291 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3292 break;
3294 case DT_PLTRELSZ:
3295 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3296 BFD_ASSERT (s != NULL);
3297 if (s->_cooked_size != 0)
3298 dyn.d_un.d_val = s->_cooked_size;
3299 else
3300 dyn.d_un.d_val = s->_raw_size;
3301 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3302 break;
3304 case DT_RELSZ:
3305 /* My reading of the SVR4 ABI indicates that the
3306 procedure linkage table relocs (DT_JMPREL) should be
3307 included in the overall relocs (DT_REL). This is
3308 what Solaris does. However, UnixWare can not handle
3309 that case. Therefore, we override the DT_RELSZ entry
3310 here to make it not include the JMPREL relocs. Since
3311 the linker script arranges for .rel.plt to follow all
3312 other relocation sections, we don't have to worry
3313 about changing the DT_REL entry. */
3314 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
3315 if (s != NULL)
3317 if (s->_cooked_size != 0)
3318 dyn.d_un.d_val -= s->_cooked_size;
3319 else
3320 dyn.d_un.d_val -= s->_raw_size;
3322 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3323 break;
3327 /* Fill in the first entry in the procedure linkage table. */
3328 if (splt->_raw_size > 0)
3329 memcpy (splt->contents, elf32_arm_plt0_entry, PLT_ENTRY_SIZE);
3331 /* UnixWare sets the entsize of .plt to 4, although that doesn't
3332 really seem like the right value. */
3333 elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
3336 /* Fill in the first three entries in the global offset table. */
3337 if (sgot->_raw_size > 0)
3339 if (sdyn == NULL)
3340 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
3341 else
3342 bfd_put_32 (output_bfd,
3343 sdyn->output_section->vma + sdyn->output_offset,
3344 sgot->contents);
3345 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
3346 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
3349 elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
3351 return true;
3354 static void
3355 elf32_arm_post_process_headers (abfd, link_info)
3356 bfd * abfd;
3357 struct bfd_link_info * link_info ATTRIBUTE_UNUSED;
3359 Elf_Internal_Ehdr * i_ehdrp; /* ELF file header, internal form. */
3361 i_ehdrp = elf_elfheader (abfd);
3363 i_ehdrp->e_ident[EI_OSABI] = ARM_ELF_OS_ABI_VERSION;
3364 i_ehdrp->e_ident[EI_ABIVERSION] = ARM_ELF_ABI_VERSION;
3367 #define ELF_ARCH bfd_arch_arm
3368 #define ELF_MACHINE_CODE EM_ARM
3369 #define ELF_MAXPAGESIZE 0x8000
3371 #define bfd_elf32_bfd_copy_private_bfd_data elf32_arm_copy_private_bfd_data
3372 #define bfd_elf32_bfd_merge_private_bfd_data elf32_arm_merge_private_bfd_data
3373 #define bfd_elf32_bfd_set_private_flags elf32_arm_set_private_flags
3374 #define bfd_elf32_bfd_print_private_bfd_data elf32_arm_print_private_bfd_data
3375 #define bfd_elf32_bfd_link_hash_table_create elf32_arm_link_hash_table_create
3376 #define bfd_elf32_bfd_reloc_type_lookup elf32_arm_reloc_type_lookup
3377 #define bfd_elf32_find_nearest_line elf32_arm_find_nearest_line
3379 #define elf_backend_get_symbol_type elf32_arm_get_symbol_type
3380 #define elf_backend_gc_mark_hook elf32_arm_gc_mark_hook
3381 #define elf_backend_gc_sweep_hook elf32_arm_gc_sweep_hook
3382 #define elf_backend_check_relocs elf32_arm_check_relocs
3383 #define elf_backend_relocate_section elf32_arm_relocate_section
3384 #define elf_backend_adjust_dynamic_symbol elf32_arm_adjust_dynamic_symbol
3385 #define elf_backend_create_dynamic_sections _bfd_elf_create_dynamic_sections
3386 #define elf_backend_finish_dynamic_symbol elf32_arm_finish_dynamic_symbol
3387 #define elf_backend_finish_dynamic_sections elf32_arm_finish_dynamic_sections
3388 #define elf_backend_size_dynamic_sections elf32_arm_size_dynamic_sections
3389 #define elf_backend_post_process_headers elf32_arm_post_process_headers
3391 #define elf_backend_can_gc_sections 1
3392 #define elf_backend_plt_readonly 1
3393 #define elf_backend_want_got_plt 1
3394 #define elf_backend_want_plt_sym 0
3396 #define elf_backend_got_header_size 12
3397 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
3399 #include "elf32-target.h"