1 /* D10V-specific support for 32-bit ELF
2 Copyright (C) 1996-2023 Free Software Foundation, Inc.
3 Contributed by Martin Hunt (hunt@cygnus.com).
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
21
22 #include "sysdep.h"
23 #include "bfd.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26 #include "elf/d10v.h"
27
28 /* Use REL instead of RELA to save space. */
29 #define USE_REL 1
30
31 static reloc_howto_type elf_d10v_howto_table[] =
32 {
33 /* This reloc does nothing. */
34 HOWTO (R_D10V_NONE, /* Type. */
35 0, /* Rightshift. */
36 0, /* Size. */
37 0, /* Bitsize. */
38 false, /* PC_relative. */
39 0, /* Bitpos. */
40 complain_overflow_dont,/* Complain_on_overflow. */
41 bfd_elf_generic_reloc, /* Special_function. */
42 "R_D10V_NONE", /* Name. */
43 false, /* Partial_inplace. */
44 0, /* Src_mask. */
45 0, /* Dst_mask. */
46 false), /* PCrel_offset. */
47
48 /* An PC Relative 10-bit relocation, shifted by 2, right container. */
49 HOWTO (R_D10V_10_PCREL_R, /* Type. */
50 2, /* Rightshift. */
51 4, /* Size. */
52 8, /* Bitsize. */
53 true, /* PC_relative. */
54 0, /* Bitpos. */
55 complain_overflow_signed, /* Complain_on_overflow. */
56 bfd_elf_generic_reloc, /* Special_function. */
57 "R_D10V_10_PCREL_R", /* Name. */
58 false, /* Partial_inplace. */
59 0xff, /* Src_mask. */
60 0xff, /* Dst_mask. */
61 true), /* PCrel_offset. */
62
63 /* An PC Relative 10-bit relocation, shifted by 2, left container. */
64 HOWTO (R_D10V_10_PCREL_L, /* Type. */
65 2, /* Rightshift. */
66 4, /* Size. */
67 8, /* Bitsize. */
68 true, /* PC_relative. */
69 15, /* Bitpos. */
70 complain_overflow_signed, /* Complain_on_overflow. */
71 bfd_elf_generic_reloc, /* Special_function. */
72 "R_D10V_10_PCREL_L", /* Name. */
73 false, /* Partial_inplace. */
74 0x07f8000, /* Src_mask. */
75 0x07f8000, /* Dst_mask. */
76 true), /* PCrel_offset. */
77
78 /* A 16 bit absolute relocation. */
79 HOWTO (R_D10V_16, /* Type. */
80 0, /* Rightshift. */
81 2, /* Size. */
82 16, /* Bitsize. */
83 false, /* PC_relative. */
84 0, /* Bitpos. */
85 complain_overflow_dont,/* Complain_on_overflow. */
86 bfd_elf_generic_reloc, /* Special_function. */
87 "R_D10V_16", /* Name. */
88 false, /* Partial_inplace. */
89 0xffff, /* Src_mask. */
90 0xffff, /* Dst_mask. */
91 false), /* PCrel_offset. */
92
93 /* An 18 bit absolute relocation, right shifted 2. */
94 HOWTO (R_D10V_18, /* Type. */
95 2, /* Rightshift. */
96 2, /* Size. */
97 16, /* Bitsize. */
98 false, /* PC_relative. */
99 0, /* Bitpos. */
100 complain_overflow_dont, /* Complain_on_overflow. */
101 bfd_elf_generic_reloc, /* Special_function. */
102 "R_D10V_18", /* Name. */
103 false, /* Partial_inplace. */
104 0xffff, /* Src_mask. */
105 0xffff, /* Dst_mask. */
106 false), /* PCrel_offset. */
107
108 /* A relative 18 bit relocation, right shifted by 2. */
109 HOWTO (R_D10V_18_PCREL, /* Type. */
110 2, /* Rightshift. */
111 4, /* Size. */
112 16, /* Bitsize. */
113 true, /* PC_relative. */
114 0, /* Bitpos. */
115 complain_overflow_signed, /* Complain_on_overflow. */
116 bfd_elf_generic_reloc, /* Special_function. */
117 "R_D10V_18_PCREL", /* Name. */
118 false, /* Partial_inplace. */
119 0xffff, /* Src_mask. */
120 0xffff, /* Dst_mask. */
121 true), /* PCrel_offset. */
122
123 /* A 32 bit absolute relocation. */
124 HOWTO (R_D10V_32, /* Type. */
125 0, /* Rightshift. */
126 4, /* Size. */
127 32, /* Bitsize. */
128 false, /* PC_relative. */
129 0, /* Bitpos. */
130 complain_overflow_dont,/* Complain_on_overflow. */
131 bfd_elf_generic_reloc, /* Special_function. */
132 "R_D10V_32", /* Name. */
133 false, /* Partial_inplace. */
134 0xffffffff, /* Src_mask. */
135 0xffffffff, /* Dst_mask. */
136 false), /* PCrel_offset. */
137
138 /* GNU extension to record C++ vtable hierarchy. */
139 HOWTO (R_D10V_GNU_VTINHERIT, /* Type. */
140 0, /* Rightshift. */
141 4, /* Size. */
142 0, /* Bitsize. */
143 false, /* PC_relative. */
144 0, /* Bitpos. */
145 complain_overflow_dont,/* Complain_on_overflow. */
146 NULL, /* Special_function. */
147 "R_D10V_GNU_VTINHERIT",/* Name. */
148 false, /* Partial_inplace. */
149 0, /* Src_mask. */
150 0, /* Dst_mask. */
151 false), /* PCrel_offset. */
152
153 /* GNU extension to record C++ vtable member usage. */
154 HOWTO (R_D10V_GNU_VTENTRY, /* Type. */
155 0, /* Rightshift. */
156 4, /* Size. */
157 0, /* Bitsize. */
158 false, /* PC_relative. */
159 0, /* Bitpos. */
160 complain_overflow_dont,/* Complain_on_overflow. */
161 _bfd_elf_rel_vtable_reloc_fn, /* Special_function. */
162 "R_D10V_GNU_VTENTRY", /* Name. */
163 false, /* Partial_inplace. */
164 0, /* Src_mask. */
165 0, /* Dst_mask. */
166 false), /* PCrel_offset. */
167 };
168
169 /* Map BFD reloc types to D10V ELF reloc types. */
170
171 struct d10v_reloc_map
172 {
173 bfd_reloc_code_real_type bfd_reloc_val;
174 unsigned char elf_reloc_val;
175 };
176
177 static const struct d10v_reloc_map d10v_reloc_map[] =
178 {
179 { BFD_RELOC_NONE, R_D10V_NONE, },
180 { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R },
181 { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L },
182 { BFD_RELOC_16, R_D10V_16 },
183 { BFD_RELOC_D10V_18, R_D10V_18 },
184 { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL },
185 { BFD_RELOC_32, R_D10V_32 },
186 { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT },
187 { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY },
188 };
189
190 static reloc_howto_type *
191 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
192 bfd_reloc_code_real_type code)
193 {
194 unsigned int i;
195
196 for (i = 0;
197 i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map);
198 i++)
199 if (d10v_reloc_map[i].bfd_reloc_val == code)
200 return &elf_d10v_howto_table[d10v_reloc_map[i].elf_reloc_val];
201
202 return NULL;
203 }
204
205 static reloc_howto_type *
206 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
207 const char *r_name)
208 {
209 unsigned int i;
210
211 for (i = 0;
212 i < sizeof (elf_d10v_howto_table) / sizeof (elf_d10v_howto_table[0]);
213 i++)
214 if (elf_d10v_howto_table[i].name != NULL
215 && strcasecmp (elf_d10v_howto_table[i].name, r_name) == 0)
216 return &elf_d10v_howto_table[i];
217
218 return NULL;
219 }
220
221 /* Set the howto pointer for an D10V ELF reloc. */
222
223 static bool
224 d10v_info_to_howto_rel (bfd *abfd,
225 arelent *cache_ptr,
226 Elf_Internal_Rela *dst)
227 {
228 unsigned int r_type;
229
230 r_type = ELF32_R_TYPE (dst->r_info);
231 if (r_type >= (unsigned int) R_D10V_max)
232 {
233 /* xgettext:c-format */
234 _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
235 abfd, r_type);
236 bfd_set_error (bfd_error_bad_value);
237 return false;
238 }
239 cache_ptr->howto = &elf_d10v_howto_table[r_type];
240 return true;
241 }
242
243 static asection *
244 elf32_d10v_gc_mark_hook (asection *sec,
245 struct bfd_link_info *info,
246 Elf_Internal_Rela *rel,
247 struct elf_link_hash_entry *h,
248 Elf_Internal_Sym *sym)
249 {
250 if (h != NULL)
251 switch (ELF32_R_TYPE (rel->r_info))
252 {
253 case R_D10V_GNU_VTINHERIT:
254 case R_D10V_GNU_VTENTRY:
255 return NULL;
256 }
257
258 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
259 }
260
261 /* Look through the relocs for a section during the first phase.
262 Since we don't do .gots or .plts, we just need to consider the
263 virtual table relocs for gc. */
264
265 static bool
266 elf32_d10v_check_relocs (bfd *abfd,
267 struct bfd_link_info *info,
268 asection *sec,
269 const Elf_Internal_Rela *relocs)
270 {
271 Elf_Internal_Shdr *symtab_hdr;
272 struct elf_link_hash_entry **sym_hashes;
273 const Elf_Internal_Rela *rel;
274 const Elf_Internal_Rela *rel_end;
275
276 if (bfd_link_relocatable (info))
277 return true;
278
279 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
280 sym_hashes = elf_sym_hashes (abfd);
281
282 rel_end = relocs + sec->reloc_count;
283 for (rel = relocs; rel < rel_end; rel++)
284 {
285 struct elf_link_hash_entry *h;
286 unsigned long r_symndx;
287
288 r_symndx = ELF32_R_SYM (rel->r_info);
289 if (r_symndx < symtab_hdr->sh_info)
290 h = NULL;
291 else
292 {
293 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
294 while (h->root.type == bfd_link_hash_indirect
295 || h->root.type == bfd_link_hash_warning)
296 h = (struct elf_link_hash_entry *) h->root.u.i.link;
297 }
298
299 switch (ELF32_R_TYPE (rel->r_info))
300 {
301 /* This relocation describes the C++ object vtable hierarchy.
302 Reconstruct it for later use during GC. */
303 case R_D10V_GNU_VTINHERIT:
304 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
305 return false;
306 break;
307
308 /* This relocation describes which C++ vtable entries are actually
309 used. Record for later use during GC. */
310 case R_D10V_GNU_VTENTRY:
311 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
312 return false;
313 break;
314 }
315 }
316
317 return true;
318 }
319
320 static bfd_vma
321 extract_rel_addend (bfd *abfd,
322 bfd_byte *where,
323 reloc_howto_type *howto)
324 {
325 bfd_vma insn, val;
326
327 switch (bfd_get_reloc_size (howto))
328 {
329 case 1:
330 insn = bfd_get_8 (abfd, where);
331 break;
332 case 2:
333 insn = bfd_get_16 (abfd, where);
334 break;
335 case 4:
336 insn = bfd_get_32 (abfd, where);
337 break;
338 default:
339 abort ();
340 }
341
342 val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
343 /* We should really be testing for signed addends here, but we don't
344 have that info directly in the howto. */
345 if (howto->pc_relative)
346 {
347 bfd_vma sign;
348 sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
349 sign = sign >> howto->bitpos << howto->rightshift;
350 val = (val ^ sign) - sign;
351 }
352 return val;
353 }
354
355 static void
356 insert_rel_addend (bfd *abfd,
357 bfd_byte *where,
358 reloc_howto_type *howto,
359 bfd_vma addend)
360 {
361 bfd_vma insn;
362
363 addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
364 insn = ~howto->dst_mask;
365 switch (bfd_get_reloc_size (howto))
366 {
367 case 1:
368 insn &= bfd_get_8 (abfd, where);
369 insn |= addend;
370 bfd_put_8 (abfd, insn, where);
371 break;
372 case 2:
373 insn &= bfd_get_16 (abfd, where);
374 insn |= addend;
375 bfd_put_16 (abfd, insn, where);
376 break;
377 case 4:
378 insn &= bfd_get_32 (abfd, where);
379 insn |= addend;
380 bfd_put_32 (abfd, insn, where);
381 break;
382 default:
383 abort ();
384 }
385 }
386
387 /* Relocate a D10V ELF section. */
388
389 static int
390 elf32_d10v_relocate_section (bfd *output_bfd,
391 struct bfd_link_info *info,
392 bfd *input_bfd,
393 asection *input_section,
394 bfd_byte *contents,
395 Elf_Internal_Rela *relocs,
396 Elf_Internal_Sym *local_syms,
397 asection **local_sections)
398 {
399 Elf_Internal_Shdr *symtab_hdr;
400 struct elf_link_hash_entry **sym_hashes;
401 Elf_Internal_Rela *rel, *relend;
402 const char *name;
403
404 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
405 sym_hashes = elf_sym_hashes (input_bfd);
406
407 rel = relocs;
408 relend = relocs + input_section->reloc_count;
409 for (; rel < relend; rel++)
410 {
411 int r_type;
412 reloc_howto_type *howto;
413 unsigned long r_symndx;
414 Elf_Internal_Sym *sym;
415 asection *sec;
416 struct elf_link_hash_entry *h;
417 bfd_vma relocation;
418 bfd_reloc_status_type r;
419
420 r_symndx = ELF32_R_SYM (rel->r_info);
421 r_type = ELF32_R_TYPE (rel->r_info);
422
423 if (r_type == R_D10V_GNU_VTENTRY
424 || r_type == R_D10V_GNU_VTINHERIT)
425 continue;
426
427 howto = elf_d10v_howto_table + r_type;
428 h = NULL;
429 sym = NULL;
430 sec = NULL;
431 if (r_symndx < symtab_hdr->sh_info)
432 {
433 sym = local_syms + r_symndx;
434 sec = local_sections[r_symndx];
435 relocation = (sec->output_section->vma
436 + sec->output_offset
437 + sym->st_value);
438 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION
439 && ((sec->flags & SEC_MERGE) != 0
440 || (bfd_link_relocatable (info)
441 && sec->output_offset != 0)))
442 {
443 bfd_vma addend;
444 bfd_byte *where = contents + rel->r_offset;
445
446 addend = extract_rel_addend (input_bfd, where, howto);
447
448 if (bfd_link_relocatable (info))
449 addend += sec->output_offset;
450 else
451 {
452 asection *msec = sec;
453 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec,
454 addend);
455 addend -= relocation;
456 addend += msec->output_section->vma + msec->output_offset;
457 }
458 insert_rel_addend (input_bfd, where, howto, addend);
459 }
460 }
461 else
462 {
463 bool unresolved_reloc, warned, ignored;
464
465 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
466 r_symndx, symtab_hdr, sym_hashes,
467 h, sec, relocation,
468 unresolved_reloc, warned, ignored);
469 }
470
471 if (sec != NULL && discarded_section (sec))
472 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
473 rel, 1, relend, howto, 0, contents);
474
475 if (bfd_link_relocatable (info))
476 continue;
477
478 if (h != NULL)
479 name = h->root.root.string;
480 else
481 {
482 name = (bfd_elf_string_from_elf_section
483 (input_bfd, symtab_hdr->sh_link, sym->st_name));
484 if (name == NULL || *name == '\0')
485 name = bfd_section_name (sec);
486 }
487
488 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
489 contents, rel->r_offset,
490 relocation, (bfd_vma) 0);
491
492 if (r != bfd_reloc_ok)
493 {
494 const char * msg = (const char *) 0;
495
496 switch (r)
497 {
498 case bfd_reloc_overflow:
499 (*info->callbacks->reloc_overflow)
500 (info, (h ? &h->root : NULL), name, howto->name,
501 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
502 break;
503
504 case bfd_reloc_undefined:
505 (*info->callbacks->undefined_symbol)
506 (info, name, input_bfd, input_section, rel->r_offset, true);
507 break;
508
509 case bfd_reloc_outofrange:
510 msg = _("internal error: out of range error");
511 goto common_error;
512
513 case bfd_reloc_notsupported:
514 msg = _("internal error: unsupported relocation error");
515 goto common_error;
516
517 case bfd_reloc_dangerous:
518 msg = _("internal error: dangerous error");
519 goto common_error;
520
521 default:
522 msg = _("internal error: unknown error");
523 /* fall through */
524
525 common_error:
526 (*info->callbacks->warning) (info, msg, name, input_bfd,
527 input_section, rel->r_offset);
528 break;
529 }
530 }
531 }
532
533 return true;
534 }
535 #define ELF_ARCH bfd_arch_d10v
536 #define ELF_MACHINE_CODE EM_D10V
537 #define ELF_MACHINE_ALT1 EM_CYGNUS_D10V
538 #define ELF_MAXPAGESIZE 0x1000
539
540 #define TARGET_BIG_SYM d10v_elf32_vec
541 #define TARGET_BIG_NAME "elf32-d10v"
542
543 #define elf_info_to_howto NULL
544 #define elf_info_to_howto_rel d10v_info_to_howto_rel
545 #define elf_backend_object_p 0
546 #define elf_backend_gc_mark_hook elf32_d10v_gc_mark_hook
547 #define elf_backend_check_relocs elf32_d10v_check_relocs
548 #define elf_backend_relocate_section elf32_d10v_relocate_section
549 #define elf_backend_can_gc_sections 1
550
551 #include "elf32-target.h"