1 /* D10V-specific support for 32-bit ELF
2 Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004
3 Free Software Foundation, Inc.
4 Contributed by Martin Hunt (hunt@cygnus.com).
5
6 This file is part of BFD, the Binary File Descriptor library.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
21
22 #include "bfd.h"
23 #include "sysdep.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26 #include "elf/d10v.h"
27
28 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
29 PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
30 static void d10v_info_to_howto_rel
31 PARAMS ((bfd *, arelent *, Elf_Internal_Rela *));
32 static asection * elf32_d10v_gc_mark_hook
33 PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *,
34 struct elf_link_hash_entry *, Elf_Internal_Sym *));
35 static bfd_boolean elf32_d10v_gc_sweep_hook
36 PARAMS ((bfd *, struct bfd_link_info *, asection *,
37 const Elf_Internal_Rela *));
38 static bfd_boolean elf32_d10v_check_relocs
39 PARAMS ((bfd *, struct bfd_link_info *, asection *,
40 const Elf_Internal_Rela *));
41 static bfd_vma extract_rel_addend
42 PARAMS ((bfd *, bfd_byte *, reloc_howto_type *));
43 static void insert_rel_addend
44 PARAMS ((bfd *, bfd_byte *, reloc_howto_type *, bfd_vma));
45 static bfd_boolean elf32_d10v_relocate_section
46 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *,
47 bfd_byte *, Elf_Internal_Rela *, Elf_Internal_Sym *,
48 asection **));
49
50 /* Use REL instead of RELA to save space. */
51 #define USE_REL 1
52
53 static reloc_howto_type elf_d10v_howto_table[] =
54 {
55 /* This reloc does nothing. */
56 HOWTO (R_D10V_NONE, /* type */
57 0, /* rightshift */
58 2, /* size (0 = byte, 1 = short, 2 = long) */
59 32, /* bitsize */
60 FALSE, /* pc_relative */
61 0, /* bitpos */
62 complain_overflow_dont, /* complain_on_overflow */
63 bfd_elf_generic_reloc, /* special_function */
64 "R_D10V_NONE", /* name */
65 FALSE, /* partial_inplace */
66 0, /* src_mask */
67 0, /* dst_mask */
68 FALSE), /* pcrel_offset */
69
70 /* An PC Relative 10-bit relocation, shifted by 2 */
71 /* right container */
72 HOWTO (R_D10V_10_PCREL_R, /* type */
73 2, /* rightshift */
74 2, /* size (0 = byte, 1 = short, 2 = long) */
75 7, /* bitsize */
76 TRUE, /* pc_relative */
77 0, /* bitpos */
78 complain_overflow_bitfield, /* complain_on_overflow */
79 bfd_elf_generic_reloc, /* special_function */
80 "R_D10V_10_PCREL_R", /* name */
81 FALSE, /* partial_inplace */
82 0xff, /* src_mask */
83 0xff, /* dst_mask */
84 TRUE), /* pcrel_offset */
85
86 /* An PC Relative 10-bit relocation, shifted by 2 */
87 /* left container */
88 HOWTO (R_D10V_10_PCREL_L, /* type */
89 2, /* rightshift */
90 2, /* size (0 = byte, 1 = short, 2 = long) */
91 7, /* bitsize */
92 TRUE, /* pc_relative */
93 15, /* bitpos */
94 complain_overflow_bitfield, /* complain_on_overflow */
95 bfd_elf_generic_reloc, /* special_function */
96 "R_D10V_10_PCREL_L", /* name */
97 FALSE, /* partial_inplace */
98 0x07f8000, /* src_mask */
99 0x07f8000, /* dst_mask */
100 TRUE), /* pcrel_offset */
101
102 /* A 16 bit absolute relocation */
103 HOWTO (R_D10V_16, /* type */
104 0, /* rightshift */
105 1, /* size (0 = byte, 1 = short, 2 = long) */
106 16, /* bitsize */
107 FALSE, /* pc_relative */
108 0, /* bitpos */
109 complain_overflow_dont, /* complain_on_overflow */
110 bfd_elf_generic_reloc, /* special_function */
111 "R_D10V_16", /* name */
112 FALSE, /* partial_inplace */
113 0xffff, /* src_mask */
114 0xffff, /* dst_mask */
115 FALSE), /* pcrel_offset */
116
117 /* An 18 bit absolute relocation, right shifted 2 */
118 HOWTO (R_D10V_18, /* type */
119 2, /* rightshift */
120 1, /* size (0 = byte, 1 = short, 2 = long) */
121 16, /* bitsize */
122 FALSE, /* pc_relative */
123 0, /* bitpos */
124 complain_overflow_dont, /* complain_on_overflow */
125 bfd_elf_generic_reloc, /* special_function */
126 "R_D10V_18", /* name */
127 FALSE, /* partial_inplace */
128 0xffff, /* src_mask */
129 0xffff, /* dst_mask */
130 FALSE), /* pcrel_offset */
131
132 /* A relative 18 bit relocation, right shifted by 2 */
133 HOWTO (R_D10V_18_PCREL, /* type */
134 2, /* rightshift */
135 2, /* size (0 = byte, 1 = short, 2 = long) */
136 15, /* bitsize */
137 TRUE, /* pc_relative */
138 0, /* bitpos */
139 complain_overflow_bitfield, /* complain_on_overflow */
140 bfd_elf_generic_reloc, /* special_function */
141 "R_D10V_18_PCREL", /* name */
142 FALSE, /* partial_inplace */
143 0xffff, /* src_mask */
144 0xffff, /* dst_mask */
145 TRUE), /* pcrel_offset */
146
147 /* A 32 bit absolute relocation */
148 HOWTO (R_D10V_32, /* type */
149 0, /* rightshift */
150 2, /* size (0 = byte, 1 = short, 2 = long) */
151 32, /* bitsize */
152 FALSE, /* pc_relative */
153 0, /* bitpos */
154 complain_overflow_dont, /* complain_on_overflow */
155 bfd_elf_generic_reloc, /* special_function */
156 "R_D10V_32", /* name */
157 FALSE, /* partial_inplace */
158 0xffffffff, /* src_mask */
159 0xffffffff, /* dst_mask */
160 FALSE), /* pcrel_offset */
161
162 /* GNU extension to record C++ vtable hierarchy */
163 HOWTO (R_D10V_GNU_VTINHERIT, /* type */
164 0, /* rightshift */
165 2, /* size (0 = byte, 1 = short, 2 = long) */
166 0, /* bitsize */
167 FALSE, /* pc_relative */
168 0, /* bitpos */
169 complain_overflow_dont, /* complain_on_overflow */
170 NULL, /* special_function */
171 "R_D10V_GNU_VTINHERIT", /* name */
172 FALSE, /* partial_inplace */
173 0, /* src_mask */
174 0, /* dst_mask */
175 FALSE), /* pcrel_offset */
176
177 /* GNU extension to record C++ vtable member usage */
178 HOWTO (R_D10V_GNU_VTENTRY, /* type */
179 0, /* rightshift */
180 2, /* size (0 = byte, 1 = short, 2 = long) */
181 0, /* bitsize */
182 FALSE, /* pc_relative */
183 0, /* bitpos */
184 complain_overflow_dont, /* complain_on_overflow */
185 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
186 "R_D10V_GNU_VTENTRY", /* name */
187 FALSE, /* partial_inplace */
188 0, /* src_mask */
189 0, /* dst_mask */
190 FALSE), /* pcrel_offset */
191 };
192
193 /* Map BFD reloc types to D10V ELF reloc types. */
194
195 struct d10v_reloc_map
196 {
197 bfd_reloc_code_real_type bfd_reloc_val;
198 unsigned char elf_reloc_val;
199 };
200
201 static const struct d10v_reloc_map d10v_reloc_map[] =
202 {
203 { BFD_RELOC_NONE, R_D10V_NONE, },
204 { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R },
205 { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L },
206 { BFD_RELOC_16, R_D10V_16 },
207 { BFD_RELOC_D10V_18, R_D10V_18 },
208 { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL },
209 { BFD_RELOC_32, R_D10V_32 },
210 { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT },
211 { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY },
212 };
213
214 static reloc_howto_type *
bfd_elf32_bfd_reloc_type_lookup(abfd,code)215 bfd_elf32_bfd_reloc_type_lookup (abfd, code)
216 bfd *abfd ATTRIBUTE_UNUSED;
217 bfd_reloc_code_real_type code;
218 {
219 unsigned int i;
220
221 for (i = 0;
222 i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map);
223 i++)
224 {
225 if (d10v_reloc_map[i].bfd_reloc_val == code)
226 return &elf_d10v_howto_table[d10v_reloc_map[i].elf_reloc_val];
227 }
228
229 return NULL;
230 }
231
232 /* Set the howto pointer for an D10V ELF reloc. */
233
234 static void
d10v_info_to_howto_rel(abfd,cache_ptr,dst)235 d10v_info_to_howto_rel (abfd, cache_ptr, dst)
236 bfd *abfd ATTRIBUTE_UNUSED;
237 arelent *cache_ptr;
238 Elf_Internal_Rela *dst;
239 {
240 unsigned int r_type;
241
242 r_type = ELF32_R_TYPE (dst->r_info);
243 BFD_ASSERT (r_type < (unsigned int) R_D10V_max);
244 cache_ptr->howto = &elf_d10v_howto_table[r_type];
245 }
246
247 static asection *
elf32_d10v_gc_mark_hook(sec,info,rel,h,sym)248 elf32_d10v_gc_mark_hook (sec, info, rel, h, sym)
249 asection *sec;
250 struct bfd_link_info *info ATTRIBUTE_UNUSED;
251 Elf_Internal_Rela *rel;
252 struct elf_link_hash_entry *h;
253 Elf_Internal_Sym *sym;
254 {
255 if (h != NULL)
256 {
257 switch (ELF32_R_TYPE (rel->r_info))
258 {
259 case R_D10V_GNU_VTINHERIT:
260 case R_D10V_GNU_VTENTRY:
261 break;
262
263 default:
264 switch (h->root.type)
265 {
266 case bfd_link_hash_defined:
267 case bfd_link_hash_defweak:
268 return h->root.u.def.section;
269
270 case bfd_link_hash_common:
271 return h->root.u.c.p->section;
272
273 default:
274 break;
275 }
276 }
277 }
278 else
279 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
280
281 return NULL;
282 }
283
284 static bfd_boolean
elf32_d10v_gc_sweep_hook(abfd,info,sec,relocs)285 elf32_d10v_gc_sweep_hook (abfd, info, sec, relocs)
286 bfd *abfd ATTRIBUTE_UNUSED;
287 struct bfd_link_info *info ATTRIBUTE_UNUSED;
288 asection *sec ATTRIBUTE_UNUSED;
289 const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
290 {
291 /* we don't use got and plt entries for d10v */
292 return TRUE;
293 }
294
295 /* Look through the relocs for a section during the first phase.
296 Since we don't do .gots or .plts, we just need to consider the
297 virtual table relocs for gc. */
298
299 static bfd_boolean
elf32_d10v_check_relocs(abfd,info,sec,relocs)300 elf32_d10v_check_relocs (abfd, info, sec, relocs)
301 bfd *abfd;
302 struct bfd_link_info *info;
303 asection *sec;
304 const Elf_Internal_Rela *relocs;
305 {
306 Elf_Internal_Shdr *symtab_hdr;
307 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
308 const Elf_Internal_Rela *rel;
309 const Elf_Internal_Rela *rel_end;
310
311 if (info->relocatable)
312 return TRUE;
313
314 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
315 sym_hashes = elf_sym_hashes (abfd);
316 sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof (Elf32_External_Sym);
317 if (!elf_bad_symtab (abfd))
318 sym_hashes_end -= symtab_hdr->sh_info;
319
320 rel_end = relocs + sec->reloc_count;
321 for (rel = relocs; rel < rel_end; rel++)
322 {
323 struct elf_link_hash_entry *h;
324 unsigned long r_symndx;
325
326 r_symndx = ELF32_R_SYM (rel->r_info);
327 if (r_symndx < symtab_hdr->sh_info)
328 h = NULL;
329 else
330 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
331
332 switch (ELF32_R_TYPE (rel->r_info))
333 {
334 /* This relocation describes the C++ object vtable hierarchy.
335 Reconstruct it for later use during GC. */
336 case R_D10V_GNU_VTINHERIT:
337 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
338 return FALSE;
339 break;
340
341 /* This relocation describes which C++ vtable entries are actually
342 used. Record for later use during GC. */
343 case R_D10V_GNU_VTENTRY:
344 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
345 return FALSE;
346 break;
347 }
348 }
349
350 return TRUE;
351 }
352
353 static bfd_vma
extract_rel_addend(abfd,where,howto)354 extract_rel_addend (abfd, where, howto)
355 bfd *abfd;
356 bfd_byte *where;
357 reloc_howto_type *howto;
358 {
359 bfd_vma insn, val;
360
361 switch (howto->size)
362 {
363 case 0:
364 insn = bfd_get_8 (abfd, where);
365 break;
366 case 1:
367 insn = bfd_get_16 (abfd, where);
368 break;
369 case 2:
370 insn = bfd_get_32 (abfd, where);
371 break;
372 default:
373 abort ();
374 }
375
376 val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
377 /* We should really be testing for signed addends here, but we don't
378 have that info directly in the howto. */
379 if (howto->pc_relative)
380 {
381 bfd_vma sign;
382 sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
383 sign = sign >> howto->bitpos << howto->rightshift;
384 val = (val ^ sign) - sign;
385 }
386 return val;
387 }
388
389 static void
insert_rel_addend(abfd,where,howto,addend)390 insert_rel_addend (abfd, where, howto, addend)
391 bfd *abfd;
392 bfd_byte *where;
393 reloc_howto_type *howto;
394 bfd_vma addend;
395 {
396 bfd_vma insn;
397
398 addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
399 insn = ~howto->dst_mask;
400 switch (howto->size)
401 {
402 case 0:
403 insn &= bfd_get_8 (abfd, where);
404 insn |= addend;
405 bfd_put_8 (abfd, insn, where);
406 break;
407 case 1:
408 insn &= bfd_get_16 (abfd, where);
409 insn |= addend;
410 bfd_put_16 (abfd, insn, where);
411 break;
412 case 2:
413 insn &= bfd_get_32 (abfd, where);
414 insn |= addend;
415 bfd_put_32 (abfd, insn, where);
416 break;
417 default:
418 abort ();
419 }
420 }
421
422 /* Relocate a D10V ELF section. */
423 static bfd_boolean
elf32_d10v_relocate_section(output_bfd,info,input_bfd,input_section,contents,relocs,local_syms,local_sections)424 elf32_d10v_relocate_section (output_bfd, info, input_bfd, input_section,
425 contents, relocs, local_syms, local_sections)
426 bfd *output_bfd;
427 struct bfd_link_info *info;
428 bfd *input_bfd;
429 asection *input_section;
430 bfd_byte *contents;
431 Elf_Internal_Rela *relocs;
432 Elf_Internal_Sym *local_syms;
433 asection **local_sections;
434 {
435 Elf_Internal_Shdr *symtab_hdr;
436 struct elf_link_hash_entry **sym_hashes;
437 Elf_Internal_Rela *rel, *relend;
438 const char *name;
439
440 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
441 sym_hashes = elf_sym_hashes (input_bfd);
442
443 rel = relocs;
444 relend = relocs + input_section->reloc_count;
445 for (; rel < relend; rel++)
446 {
447 int r_type;
448 reloc_howto_type *howto;
449 unsigned long r_symndx;
450 Elf_Internal_Sym *sym;
451 asection *sec;
452 struct elf_link_hash_entry *h;
453 bfd_vma relocation;
454 bfd_reloc_status_type r;
455
456 r_symndx = ELF32_R_SYM (rel->r_info);
457 r_type = ELF32_R_TYPE (rel->r_info);
458
459 if (r_type == R_D10V_GNU_VTENTRY
460 || r_type == R_D10V_GNU_VTINHERIT )
461 continue;
462
463 howto = elf_d10v_howto_table + r_type;
464
465 if (info->relocatable)
466 {
467 bfd_vma val;
468 bfd_byte *where;
469
470 /* This is a relocatable link. We don't have to change
471 anything, unless the reloc is against a section symbol,
472 in which case we have to adjust according to where the
473 section symbol winds up in the output section. */
474 if (r_symndx >= symtab_hdr->sh_info)
475 continue;
476
477 sym = local_syms + r_symndx;
478 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
479 continue;
480
481 sec = local_sections[r_symndx];
482 val = sec->output_offset;
483 if (val == 0)
484 continue;
485
486 where = contents + rel->r_offset;
487 val += extract_rel_addend (input_bfd, where, howto);
488 insert_rel_addend (input_bfd, where, howto, val);
489 continue;
490 }
491
492 /* This is a final link. */
493 h = NULL;
494 sym = NULL;
495 sec = NULL;
496 if (r_symndx < symtab_hdr->sh_info)
497 {
498 sym = local_syms + r_symndx;
499 sec = local_sections[r_symndx];
500 relocation = (sec->output_section->vma
501 + sec->output_offset
502 + sym->st_value);
503 if ((sec->flags & SEC_MERGE)
504 && ELF_ST_TYPE (sym->st_info) == STT_SECTION)
505 {
506 asection *msec;
507 bfd_vma addend;
508 bfd_byte *where = contents + rel->r_offset;
509
510 addend = extract_rel_addend (input_bfd, where, howto);
511 msec = sec;
512 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, addend);
513 addend -= relocation;
514 addend += msec->output_section->vma + msec->output_offset;
515 insert_rel_addend (input_bfd, where, howto, addend);
516 }
517 }
518 else
519 {
520 bfd_boolean unresolved_reloc, warned;
521
522 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
523 r_symndx, symtab_hdr, sym_hashes,
524 h, sec, relocation,
525 unresolved_reloc, warned);
526 }
527
528 if (h != NULL)
529 name = h->root.root.string;
530 else
531 {
532 name = (bfd_elf_string_from_elf_section
533 (input_bfd, symtab_hdr->sh_link, sym->st_name));
534 if (name == NULL || *name == '\0')
535 name = bfd_section_name (input_bfd, sec);
536 }
537
538 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
539 contents, rel->r_offset,
540 relocation, (bfd_vma) 0);
541
542 if (r != bfd_reloc_ok)
543 {
544 const char * msg = (const char *) 0;
545
546 switch (r)
547 {
548 case bfd_reloc_overflow:
549 if (!((*info->callbacks->reloc_overflow)
550 (info, name, howto->name, (bfd_vma) 0,
551 input_bfd, input_section, rel->r_offset)))
552 return FALSE;
553 break;
554
555 case bfd_reloc_undefined:
556 if (!((*info->callbacks->undefined_symbol)
557 (info, name, input_bfd, input_section,
558 rel->r_offset, TRUE)))
559 return FALSE;
560 break;
561
562 case bfd_reloc_outofrange:
563 msg = _("internal error: out of range error");
564 goto common_error;
565
566 case bfd_reloc_notsupported:
567 msg = _("internal error: unsupported relocation error");
568 goto common_error;
569
570 case bfd_reloc_dangerous:
571 msg = _("internal error: dangerous error");
572 goto common_error;
573
574 default:
575 msg = _("internal error: unknown error");
576 /* fall through */
577
578 common_error:
579 if (!((*info->callbacks->warning)
580 (info, msg, name, input_bfd, input_section,
581 rel->r_offset)))
582 return FALSE;
583 break;
584 }
585 }
586 }
587
588 return TRUE;
589 }
590 #define ELF_ARCH bfd_arch_d10v
591 #define ELF_MACHINE_CODE EM_D10V
592 #define ELF_MACHINE_ALT1 EM_CYGNUS_D10V
593 #define ELF_MAXPAGESIZE 0x1000
594
595 #define TARGET_BIG_SYM bfd_elf32_d10v_vec
596 #define TARGET_BIG_NAME "elf32-d10v"
597
598 #define elf_info_to_howto 0
599 #define elf_info_to_howto_rel d10v_info_to_howto_rel
600 #define elf_backend_object_p 0
601 #define elf_backend_final_write_processing 0
602 #define elf_backend_gc_mark_hook elf32_d10v_gc_mark_hook
603 #define elf_backend_gc_sweep_hook elf32_d10v_gc_sweep_hook
604 #define elf_backend_check_relocs elf32_d10v_check_relocs
605 #define elf_backend_relocate_section elf32_d10v_relocate_section
606 #define elf_backend_can_gc_sections 1
607
608 #include "elf32-target.h"
609