1 /* BFD back-end for Intel 960 COFF files.
2 Copyright (C) 1990-2016 Free Software Foundation, Inc.
3 Written by Cygnus Support.
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 #define I960 1
23 #define BADMAG(x) I960BADMAG(x)
24
25 #include "sysdep.h"
26 #include "bfd.h"
27 #include "libbfd.h"
28 #include "coff/i960.h"
29 #include "coff/internal.h"
30
31 #ifndef bfd_pe_print_pdata
32 #define bfd_pe_print_pdata NULL
33 #endif
34
35 #include "libcoff.h" /* To allow easier abstraction-breaking. */
36
37
38 #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (3)
39 #define COFF_ALIGN_IN_SECTION_HEADER 1
40
41 #define GET_SCNHDR_ALIGN H_GET_32
42 #define PUT_SCNHDR_ALIGN H_PUT_32
43
44 /* The i960 does not support an MMU, so COFF_PAGE_SIZE can be
45 arbitrarily small. */
46 #define COFF_PAGE_SIZE 1
47
48 #define COFF_LONG_FILENAMES
49
50 /* This set of local label names is taken from gas. */
51
52 static bfd_boolean
coff_i960_is_local_label_name(bfd * abfd ATTRIBUTE_UNUSED,const char * name)53 coff_i960_is_local_label_name (bfd *abfd ATTRIBUTE_UNUSED, const char *name)
54 {
55 return (name[0] == 'L'
56 || (name[0] == '.'
57 && (name[1] == 'C'
58 || name[1] == 'I'
59 || name[1] == '.')));
60 }
61
62 /* This is just like the usual CALC_ADDEND, but it includes the
63 section VMA for PC relative relocs. */
64 #ifndef CALC_ADDEND
65 #define CALC_ADDEND(abfd, ptr, reloc, cache_ptr) \
66 { \
67 coff_symbol_type *coffsym = (coff_symbol_type *) NULL; \
68 if (ptr && bfd_asymbol_bfd (ptr) != abfd) \
69 coffsym = (obj_symbols (abfd) \
70 + (cache_ptr->sym_ptr_ptr - symbols)); \
71 else if (ptr) \
72 coffsym = coff_symbol_from (ptr); \
73 if (coffsym != (coff_symbol_type *) NULL \
74 && coffsym->native->u.syment.n_scnum == 0) \
75 cache_ptr->addend = 0; \
76 else if (ptr && bfd_asymbol_bfd (ptr) == abfd \
77 && ptr->section != (asection *) NULL) \
78 cache_ptr->addend = - (ptr->section->vma + ptr->value); \
79 else \
80 cache_ptr->addend = 0; \
81 if (ptr && (reloc.r_type == 25 || reloc.r_type == 27)) \
82 cache_ptr->addend += asect->vma; \
83 }
84 #endif
85
86 #define CALLS 0x66003800 /* Template for 'calls' instruction */
87 #define BAL 0x0b000000 /* Template for 'bal' instruction */
88 #define BAL_MASK 0x00ffffff
89
90 static bfd_reloc_status_type
optcall_callback(bfd * abfd,arelent * reloc_entry,asymbol * symbol_in,void * data,asection * input_section,bfd * ignore_bfd ATTRIBUTE_UNUSED,char ** error_message)91 optcall_callback (bfd *abfd,
92 arelent *reloc_entry,
93 asymbol *symbol_in,
94 void * data,
95 asection *input_section,
96 bfd *ignore_bfd ATTRIBUTE_UNUSED,
97 char **error_message)
98 {
99 /* This item has already been relocated correctly, but we may be
100 * able to patch in yet better code - done by digging out the
101 * correct info on this symbol */
102 bfd_reloc_status_type result;
103 coff_symbol_type *cs = coffsymbol(symbol_in);
104
105 /* Don't do anything with symbols which aren't tied up yet,
106 except move the reloc. */
107 if (bfd_is_und_section (cs->symbol.section)) {
108 reloc_entry->address += input_section->output_offset;
109 return bfd_reloc_ok;
110 }
111
112 /* So the target symbol has to be of coff type, and the symbol
113 has to have the correct native information within it */
114 if ((bfd_asymbol_flavour(&cs->symbol) != bfd_target_coff_flavour)
115 || (cs->native == (combined_entry_type *)NULL))
116 {
117 /* This is interesting, consider the case where we're outputting coff
118 from a mix n match input, linking from coff to a symbol defined in a
119 bout file will cause this match to be true. Should I complain? This
120 will only work if the bout symbol is non leaf. */
121 *error_message =
122 (char *) _("uncertain calling convention for non-COFF symbol");
123 result = bfd_reloc_dangerous;
124 }
125 else
126 {
127 switch (cs->native->u.syment.n_sclass)
128 {
129 case C_LEAFSTAT:
130 case C_LEAFEXT:
131 /* This is a call to a leaf procedure, replace instruction with a bal
132 to the correct location. */
133 {
134 union internal_auxent *aux = &((cs->native+2)->u.auxent);
135 int word = bfd_get_32 (abfd, (bfd_byte *)data + reloc_entry->address);
136 int olf = (aux->x_bal.x_balntry - cs->native->u.syment.n_value);
137 BFD_ASSERT(cs->native->u.syment.n_numaux==2);
138
139 /* We replace the original call instruction with a bal to
140 the bal entry point - the offset of which is described in
141 the 2nd auxent of the original symbol. We keep the native
142 sym and auxents untouched, so the delta between the two
143 is the offset of the bal entry point. */
144 word = ((word + olf) & BAL_MASK) | BAL;
145 bfd_put_32 (abfd, (bfd_vma) word,
146 (bfd_byte *) data + reloc_entry->address);
147 }
148 result = bfd_reloc_ok;
149 break;
150 case C_SCALL:
151 /* This is a call to a system call, replace with a calls to # */
152 BFD_ASSERT(0);
153 result = bfd_reloc_ok;
154 break;
155 default:
156 result = bfd_reloc_ok;
157 break;
158 }
159 }
160 return result;
161 }
162
163 /* i960 COFF is used by VxWorks 5.1. However, VxWorks 5.1 does not
164 appear to correctly handle a reloc against a symbol defined in the
165 same object file. It appears to simply discard such relocs, rather
166 than adding their values into the object file. We handle this here
167 by converting all relocs against defined symbols into relocs
168 against the section symbol, when generating a relocatable output
169 file.
170
171 Note that this function is only called if we are not using the COFF
172 specific backend linker. It only does something when doing a
173 relocatable link, which will almost certainly fail when not
174 generating COFF i960 output, so this function is actually no longer
175 useful. It was used before this target was converted to use the
176 COFF specific backend linker. */
177
178 static bfd_reloc_status_type
coff_i960_relocate(bfd * abfd,arelent * reloc_entry,asymbol * symbol,void * data ATTRIBUTE_UNUSED,asection * input_section ATTRIBUTE_UNUSED,bfd * output_bfd,char ** error_message ATTRIBUTE_UNUSED)179 coff_i960_relocate (bfd *abfd,
180 arelent *reloc_entry,
181 asymbol *symbol,
182 void * data ATTRIBUTE_UNUSED,
183 asection *input_section ATTRIBUTE_UNUSED,
184 bfd *output_bfd,
185 char **error_message ATTRIBUTE_UNUSED)
186 {
187 asection *osec;
188
189 if (output_bfd == NULL)
190 {
191 /* Not generating relocatable output file. */
192 return bfd_reloc_continue;
193 }
194
195 if (bfd_is_und_section (bfd_get_section (symbol)))
196 {
197 /* Symbol is not defined, so no need to worry about it. */
198 return bfd_reloc_continue;
199 }
200
201 if (bfd_is_com_section (bfd_get_section (symbol)))
202 {
203 /* I don't really know what the right action is for a common
204 symbol. */
205 return bfd_reloc_continue;
206 }
207
208 /* Convert the reloc to use the section symbol. FIXME: This method
209 is ridiculous. */
210 osec = bfd_get_section (symbol)->output_section;
211 if (coff_section_data (output_bfd, osec) != NULL
212 && coff_section_data (output_bfd, osec)->tdata != NULL)
213 reloc_entry->sym_ptr_ptr =
214 (asymbol **) coff_section_data (output_bfd, osec)->tdata;
215 else
216 {
217 const char *sec_name;
218 asymbol **syms, **sym_end;
219
220 sec_name = bfd_get_section_name (output_bfd, osec);
221 syms = bfd_get_outsymbols (output_bfd);
222 sym_end = syms + bfd_get_symcount (output_bfd);
223 for (; syms < sym_end; syms++)
224 {
225 if (bfd_asymbol_name (*syms) != NULL
226 && (*syms)->value == 0
227 && strcmp ((*syms)->section->output_section->name,
228 sec_name) == 0)
229 break;
230 }
231
232 if (syms >= sym_end)
233 abort ();
234
235 reloc_entry->sym_ptr_ptr = syms;
236
237 if (coff_section_data (output_bfd, osec) == NULL)
238 {
239 bfd_size_type amt = sizeof (struct coff_section_tdata);
240 osec->used_by_bfd = bfd_zalloc (abfd, amt);
241 if (osec->used_by_bfd == NULL)
242 return bfd_reloc_overflow;
243 }
244 coff_section_data (output_bfd, osec)->tdata = syms;
245 }
246
247 /* Let bfd_perform_relocation do its thing, which will include
248 stuffing the symbol addend into the object file. */
249 return bfd_reloc_continue;
250 }
251
252 static reloc_howto_type howto_rellong =
253 HOWTO ((unsigned int) R_RELLONG, 0, 2, 32,FALSE, 0,
254 complain_overflow_bitfield, coff_i960_relocate,"rellong", TRUE,
255 0xffffffff, 0xffffffff, 0);
256 static reloc_howto_type howto_iprmed =
257 HOWTO (R_IPRMED, 0, 2, 24,TRUE,0, complain_overflow_signed,
258 coff_i960_relocate, "iprmed ", TRUE, 0x00ffffff, 0x00ffffff, 0);
259 static reloc_howto_type howto_optcall =
260 HOWTO (R_OPTCALL, 0,2,24,TRUE,0, complain_overflow_signed,
261 optcall_callback, "optcall", TRUE, 0x00ffffff, 0x00ffffff, 0);
262
263 static reloc_howto_type *
coff_i960_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)264 coff_i960_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
265 bfd_reloc_code_real_type code)
266 {
267 switch (code)
268 {
269 default:
270 return 0;
271 case BFD_RELOC_I960_CALLJ:
272 return &howto_optcall;
273 case BFD_RELOC_32:
274 case BFD_RELOC_CTOR:
275 return &howto_rellong;
276 case BFD_RELOC_24_PCREL:
277 return &howto_iprmed;
278 }
279 }
280
281 static reloc_howto_type *
coff_i960_reloc_name_lookup(bfd * abfd ATTRIBUTE_UNUSED,const char * r_name)282 coff_i960_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
283 const char *r_name)
284 {
285 if (strcasecmp (howto_optcall.name, r_name) == 0)
286 return &howto_optcall;
287 if (strcasecmp (howto_rellong.name, r_name) == 0)
288 return &howto_rellong;
289 if (strcasecmp (howto_iprmed.name, r_name) == 0)
290 return &howto_iprmed;
291
292 return NULL;
293 }
294
295 /* The real code is in coffcode.h */
296
297 #define RTYPE2HOWTO(cache_ptr, dst) \
298 { \
299 reloc_howto_type *howto_ptr; \
300 switch ((dst)->r_type) { \
301 case 17: howto_ptr = &howto_rellong; break; \
302 case 25: howto_ptr = &howto_iprmed; break; \
303 case 27: howto_ptr = &howto_optcall; break; \
304 default: howto_ptr = 0; break; \
305 } \
306 (cache_ptr)->howto = howto_ptr; \
307 }
308
309 /* i960 COFF is used by VxWorks 5.1. However, VxWorks 5.1 does not
310 appear to correctly handle a reloc against a symbol defined in the
311 same object file. It appears to simply discard such relocs, rather
312 than adding their values into the object file. We handle this by
313 converting all relocs against global symbols into relocs against
314 internal symbols at the start of the section. This routine is
315 called at the start of the linking process, and it creates the
316 necessary symbols. */
317
318 static bfd_boolean
coff_i960_start_final_link(bfd * abfd,struct bfd_link_info * info)319 coff_i960_start_final_link (bfd *abfd, struct bfd_link_info *info)
320 {
321 bfd_size_type symesz = bfd_coff_symesz (abfd);
322 asection *o;
323 bfd_byte *esym;
324
325 if (! bfd_link_relocatable (info))
326 return TRUE;
327
328 esym = (bfd_byte *) bfd_malloc (symesz);
329 if (esym == NULL)
330 return FALSE;
331
332 if (bfd_seek (abfd, obj_sym_filepos (abfd), SEEK_SET) != 0)
333 return FALSE;
334
335 for (o = abfd->sections; o != NULL; o = o->next)
336 {
337 struct internal_syment isym;
338
339 strncpy (isym._n._n_name, o->name, SYMNMLEN);
340 isym.n_value = 0;
341 isym.n_scnum = o->target_index;
342 isym.n_type = T_NULL;
343 isym.n_sclass = C_STAT;
344 isym.n_numaux = 0;
345
346 bfd_coff_swap_sym_out (abfd, &isym, esym);
347
348 if (bfd_bwrite (esym, symesz, abfd) != symesz)
349 {
350 free (esym);
351 return FALSE;
352 }
353
354 obj_raw_syment_count (abfd) += 1;
355 }
356
357 free (esym);
358
359 return TRUE;
360 }
361
362 /* The reloc processing routine for the optimized COFF linker. */
363
364 static bfd_boolean
coff_i960_relocate_section(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,bfd * input_bfd,asection * input_section,bfd_byte * contents,struct internal_reloc * relocs,struct internal_syment * syms,asection ** sections)365 coff_i960_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
366 struct bfd_link_info *info,
367 bfd *input_bfd,
368 asection *input_section,
369 bfd_byte *contents,
370 struct internal_reloc *relocs,
371 struct internal_syment *syms,
372 asection **sections)
373 {
374 struct internal_reloc *rel;
375 struct internal_reloc *relend;
376
377 rel = relocs;
378 relend = rel + input_section->reloc_count;
379 for (; rel < relend; rel++)
380 {
381 long symndx;
382 struct coff_link_hash_entry *h;
383 struct internal_syment *sym;
384 bfd_vma addend;
385 bfd_vma val;
386 reloc_howto_type *howto;
387 bfd_reloc_status_type rstat = bfd_reloc_ok;
388 bfd_boolean done;
389
390 symndx = rel->r_symndx;
391
392 if (symndx == -1)
393 {
394 h = NULL;
395 sym = NULL;
396 }
397 else
398 {
399 h = obj_coff_sym_hashes (input_bfd)[symndx];
400 sym = syms + symndx;
401 }
402
403 if (sym != NULL && sym->n_scnum != 0)
404 addend = - sym->n_value;
405 else
406 addend = 0;
407
408 switch (rel->r_type)
409 {
410 case 17: howto = &howto_rellong; break;
411 case 25: howto = &howto_iprmed; break;
412 case 27: howto = &howto_optcall; break;
413 default:
414 bfd_set_error (bfd_error_bad_value);
415 return FALSE;
416 }
417
418 val = 0;
419
420 if (h == NULL)
421 {
422 asection *sec;
423
424 if (symndx == -1)
425 {
426 sec = bfd_abs_section_ptr;
427 val = 0;
428 }
429 else
430 {
431 sec = sections[symndx];
432 val = (sec->output_section->vma
433 + sec->output_offset
434 + sym->n_value
435 - sec->vma);
436 }
437 }
438 else
439 {
440 if (h->root.type == bfd_link_hash_defined
441 || h->root.type == bfd_link_hash_defweak)
442 {
443 asection *sec;
444
445 sec = h->root.u.def.section;
446 val = (h->root.u.def.value
447 + sec->output_section->vma
448 + sec->output_offset);
449 }
450 else if (! bfd_link_relocatable (info))
451 (*info->callbacks->undefined_symbol)
452 (info, h->root.root.string, input_bfd, input_section,
453 rel->r_vaddr - input_section->vma, TRUE);
454 }
455
456 done = FALSE;
457
458 if (howto->type == R_OPTCALL && ! bfd_link_relocatable (info) && symndx != -1)
459 {
460 int class_val;
461
462 if (h != NULL)
463 class_val = h->symbol_class;
464 else
465 class_val = sym->n_sclass;
466
467 switch (class_val)
468 {
469 case C_NULL:
470 /* This symbol is apparently not from a COFF input file.
471 We warn, and then assume that it is not a leaf
472 function. */
473 (*info->callbacks->reloc_dangerous)
474 (info,
475 _("uncertain calling convention for non-COFF symbol"),
476 input_bfd, input_section,
477 rel->r_vaddr - input_section->vma);
478 break;
479 case C_LEAFSTAT:
480 case C_LEAFEXT:
481 /* This is a call to a leaf procedure; use the bal
482 instruction. */
483 {
484 long olf;
485 unsigned long word;
486
487 if (h != NULL)
488 {
489 BFD_ASSERT (h->numaux == 2);
490 olf = h->aux[1].x_bal.x_balntry;
491 }
492 else
493 {
494 bfd_byte *esyms;
495 union internal_auxent aux;
496
497 BFD_ASSERT (sym->n_numaux == 2);
498 esyms = (bfd_byte *) obj_coff_external_syms (input_bfd);
499 esyms += (symndx + 2) * bfd_coff_symesz (input_bfd);
500 bfd_coff_swap_aux_in (input_bfd, esyms, sym->n_type,
501 sym->n_sclass, 1, sym->n_numaux,
502 &aux);
503 olf = aux.x_bal.x_balntry;
504 }
505
506 word = bfd_get_32 (input_bfd,
507 (contents
508 + (rel->r_vaddr - input_section->vma)));
509 word = ((word + olf - val) & BAL_MASK) | BAL;
510 bfd_put_32 (input_bfd,
511 (bfd_vma) word,
512 contents + (rel->r_vaddr - input_section->vma));
513 done = TRUE;
514 }
515 break;
516 case C_SCALL:
517 BFD_ASSERT (0);
518 break;
519 }
520 }
521
522 if (! done)
523 {
524 if (howto->pc_relative)
525 addend += input_section->vma;
526 rstat = _bfd_final_link_relocate (howto, input_bfd, input_section,
527 contents,
528 rel->r_vaddr - input_section->vma,
529 val, addend);
530 }
531
532 switch (rstat)
533 {
534 default:
535 abort ();
536 case bfd_reloc_ok:
537 break;
538 case bfd_reloc_overflow:
539 {
540 const char *name;
541 char buf[SYMNMLEN + 1];
542
543 if (symndx == -1)
544 name = "*ABS*";
545 else if (h != NULL)
546 name = NULL;
547 else
548 {
549 name = _bfd_coff_internal_syment_name (input_bfd, sym, buf);
550 if (name == NULL)
551 return FALSE;
552 }
553
554 (*info->callbacks->reloc_overflow)
555 (info, (h ? &h->root : NULL), name, howto->name,
556 (bfd_vma) 0, input_bfd, input_section,
557 rel->r_vaddr - input_section->vma);
558 }
559 }
560 }
561
562 return TRUE;
563 }
564
565 /* Adjust the symbol index of any reloc against a global symbol to
566 instead be a reloc against the internal symbol we created specially
567 for the section. */
568
569 static bfd_boolean
coff_i960_adjust_symndx(bfd * obfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED,bfd * ibfd,asection * sec ATTRIBUTE_UNUSED,struct internal_reloc * irel,bfd_boolean * adjustedp)570 coff_i960_adjust_symndx (bfd *obfd ATTRIBUTE_UNUSED,
571 struct bfd_link_info *info ATTRIBUTE_UNUSED,
572 bfd *ibfd,
573 asection *sec ATTRIBUTE_UNUSED,
574 struct internal_reloc *irel,
575 bfd_boolean *adjustedp)
576 {
577 struct coff_link_hash_entry *h;
578
579 *adjustedp = FALSE;
580
581 h = obj_coff_sym_hashes (ibfd)[irel->r_symndx];
582 if (h == NULL
583 || (h->root.type != bfd_link_hash_defined
584 && h->root.type != bfd_link_hash_defweak))
585 return TRUE;
586
587 irel->r_symndx = h->root.u.def.section->output_section->target_index - 1;
588 *adjustedp = TRUE;
589
590 return TRUE;
591 }
592
593 #define coff_bfd_is_local_label_name coff_i960_is_local_label_name
594
595 #define coff_start_final_link coff_i960_start_final_link
596
597 #define coff_relocate_section coff_i960_relocate_section
598
599 #define coff_adjust_symndx coff_i960_adjust_symndx
600
601 #define coff_bfd_reloc_type_lookup coff_i960_reloc_type_lookup
602 #define coff_bfd_reloc_name_lookup coff_i960_reloc_name_lookup
603
604 #include "coffcode.h"
605
606 extern const bfd_target icoff_be_vec;
607
608 CREATE_LITTLE_COFF_TARGET_VEC (icoff_le_vec, "coff-Intel-little", 0, 0, '_', & icoff_be_vec, COFF_SWAP_TABLE)
609
610 const bfd_target icoff_be_vec =
611 {
612 "coff-Intel-big", /* name */
613 bfd_target_coff_flavour,
614 BFD_ENDIAN_LITTLE, /* data byte order is little */
615 BFD_ENDIAN_BIG, /* header byte order is big */
616
617 (HAS_RELOC | EXEC_P | /* object flags */
618 HAS_LINENO | HAS_DEBUG |
619 HAS_SYMS | HAS_LOCALS | WP_TEXT),
620
621 (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
622 '_', /* leading underscore */
623 '/', /* ar_pad_char */
624 15, /* ar_max_namelen */
625 0, /* match priority. */
626
627 bfd_getl64, bfd_getl_signed_64, bfd_putl64,
628 bfd_getl32, bfd_getl_signed_32, bfd_putl32,
629 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
630 bfd_getb64, bfd_getb_signed_64, bfd_putb64,
631 bfd_getb32, bfd_getb_signed_32, bfd_putb32,
632 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
633
634 {_bfd_dummy_target, coff_object_p, /* bfd_check_format */
635 bfd_generic_archive_p, _bfd_dummy_target},
636 {bfd_false, coff_mkobject, /* bfd_set_format */
637 _bfd_generic_mkarchive, bfd_false},
638 {bfd_false, coff_write_object_contents, /* bfd_write_contents */
639 _bfd_write_archive_contents, bfd_false},
640
641 BFD_JUMP_TABLE_GENERIC (coff),
642 BFD_JUMP_TABLE_COPY (coff),
643 BFD_JUMP_TABLE_CORE (_bfd_nocore),
644 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
645 BFD_JUMP_TABLE_SYMBOLS (coff),
646 BFD_JUMP_TABLE_RELOCS (coff),
647 BFD_JUMP_TABLE_WRITE (coff),
648 BFD_JUMP_TABLE_LINK (coff),
649 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
650
651 & icoff_le_vec,
652
653 COFF_SWAP_TABLE
654 };
655