1 /* Xstormy16-specific support for 32-bit ELF.
2 Copyright (C) 2000-2020 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
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 3 of the License, or
9 (at your option) any later version.
10
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.
15
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., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
20
21 #include "sysdep.h"
22 #include "bfd.h"
23 #include "libbfd.h"
24 #include "elf-bfd.h"
25 #include "elf/xstormy16.h"
26 #include "libiberty.h"
27
28 /* Handle the R_XSTORMY16_24 reloc, which has an odd bit arrangement. */
29
30 static bfd_reloc_status_type
xstormy16_elf_24_reloc(bfd * abfd,arelent * reloc_entry,asymbol * symbol,void * data,asection * input_section,bfd * output_bfd,char ** error_message ATTRIBUTE_UNUSED)31 xstormy16_elf_24_reloc (bfd *abfd,
32 arelent *reloc_entry,
33 asymbol *symbol,
34 void * data,
35 asection *input_section,
36 bfd *output_bfd,
37 char **error_message ATTRIBUTE_UNUSED)
38 {
39 bfd_vma relocation, x;
40
41 if (output_bfd != NULL)
42 {
43 reloc_entry->address += input_section->output_offset;
44 return bfd_reloc_ok;
45 }
46
47 if (reloc_entry->address > bfd_get_section_limit (abfd, input_section))
48 return bfd_reloc_outofrange;
49
50 if (bfd_is_com_section (symbol->section))
51 relocation = 0;
52 else
53 relocation = symbol->value;
54
55 relocation += symbol->section->output_section->vma;
56 relocation += symbol->section->output_offset;
57 relocation += reloc_entry->addend;
58
59 x = bfd_get_32 (abfd, (bfd_byte *) data + reloc_entry->address);
60 x &= 0x0000ff00;
61 x |= relocation & 0xff;
62 x |= (relocation << 8) & 0xffff0000;
63 bfd_put_32 (abfd, x, (bfd_byte *) data + reloc_entry->address);
64
65 if (relocation & ~ (bfd_vma) 0xffffff)
66 return bfd_reloc_overflow;
67
68 return bfd_reloc_ok;
69 }
70
71 static reloc_howto_type xstormy16_elf_howto_table [] =
72 {
73 /* This reloc does nothing. */
74 HOWTO (R_XSTORMY16_NONE, /* type */
75 0, /* rightshift */
76 3, /* size (0 = byte, 1 = short, 2 = long) */
77 0, /* bitsize */
78 FALSE, /* pc_relative */
79 0, /* bitpos */
80 complain_overflow_dont, /* complain_on_overflow */
81 bfd_elf_generic_reloc, /* special_function */
82 "R_XSTORMY16_NONE", /* name */
83 FALSE, /* partial_inplace */
84 0, /* src_mask */
85 0, /* dst_mask */
86 FALSE), /* pcrel_offset */
87
88 /* A 32 bit absolute relocation. */
89 HOWTO (R_XSTORMY16_32, /* type */
90 0, /* rightshift */
91 2, /* size (0 = byte, 1 = short, 2 = long) */
92 32, /* bitsize */
93 FALSE, /* pc_relative */
94 0, /* bitpos */
95 complain_overflow_dont, /* complain_on_overflow */
96 bfd_elf_generic_reloc, /* special_function */
97 "R_XSTORMY16_32", /* name */
98 FALSE, /* partial_inplace */
99 0, /* src_mask */
100 0xffffffff, /* dst_mask */
101 FALSE), /* pcrel_offset */
102
103 /* A 16 bit absolute relocation. */
104 HOWTO (R_XSTORMY16_16, /* type */
105 0, /* rightshift */
106 1, /* size (0 = byte, 1 = short, 2 = long) */
107 16, /* bitsize */
108 FALSE, /* pc_relative */
109 0, /* bitpos */
110 complain_overflow_bitfield, /* complain_on_overflow */
111 bfd_elf_generic_reloc, /* special_function */
112 "R_XSTORMY16_16", /* name */
113 FALSE, /* partial_inplace */
114 0, /* src_mask */
115 0xffff, /* dst_mask */
116 FALSE), /* pcrel_offset */
117
118 /* An 8 bit absolute relocation. */
119 HOWTO (R_XSTORMY16_8, /* type */
120 0, /* rightshift */
121 0, /* size (0 = byte, 1 = short, 2 = long) */
122 8, /* bitsize */
123 FALSE, /* pc_relative */
124 0, /* bitpos */
125 complain_overflow_unsigned, /* complain_on_overflow */
126 bfd_elf_generic_reloc, /* special_function */
127 "R_XSTORMY16_8", /* name */
128 FALSE, /* partial_inplace */
129 0, /* src_mask */
130 0xff, /* dst_mask */
131 FALSE), /* pcrel_offset */
132
133 /* A 32 bit pc-relative relocation. */
134 HOWTO (R_XSTORMY16_PC32, /* type */
135 0, /* rightshift */
136 2, /* size (0 = byte, 1 = short, 2 = long) */
137 32, /* bitsize */
138 TRUE, /* pc_relative */
139 0, /* bitpos */
140 complain_overflow_dont, /* complain_on_overflow */
141 bfd_elf_generic_reloc, /* special_function */
142 "R_XSTORMY16_PC32", /* name */
143 FALSE, /* partial_inplace */
144 0, /* src_mask */
145 0xffffffff, /* dst_mask */
146 TRUE), /* pcrel_offset */
147
148 /* A 16 bit pc-relative relocation. */
149 HOWTO (R_XSTORMY16_PC16, /* type */
150 0, /* rightshift */
151 1, /* size (0 = byte, 1 = short, 2 = long) */
152 16, /* bitsize */
153 TRUE, /* pc_relative */
154 0, /* bitpos */
155 complain_overflow_signed, /* complain_on_overflow */
156 bfd_elf_generic_reloc, /* special_function */
157 "R_XSTORMY16_PC16", /* name */
158 FALSE, /* partial_inplace */
159 0, /* src_mask */
160 0xffffffff, /* dst_mask */
161 TRUE), /* pcrel_offset */
162
163 /* An 8 bit pc-relative relocation. */
164 HOWTO (R_XSTORMY16_PC8, /* type */
165 0, /* rightshift */
166 0, /* size (0 = byte, 1 = short, 2 = long) */
167 8, /* bitsize */
168 TRUE, /* pc_relative */
169 0, /* bitpos */
170 complain_overflow_signed, /* complain_on_overflow */
171 bfd_elf_generic_reloc, /* special_function */
172 "R_XSTORMY16_PC8", /* name */
173 FALSE, /* partial_inplace */
174 0, /* src_mask */
175 0xffffffff, /* dst_mask */
176 TRUE), /* pcrel_offset */
177
178 /* A 12-bit pc-relative relocation suitable for the branch instructions. */
179 HOWTO (R_XSTORMY16_REL_12, /* type */
180 1, /* rightshift */
181 1, /* size (0 = byte, 1 = short, 2 = long) */
182 11, /* bitsize */
183 TRUE, /* pc_relative */
184 1, /* bitpos */
185 complain_overflow_signed, /* complain_on_overflow */
186 bfd_elf_generic_reloc, /* special_function */
187 "R_XSTORMY16_REL_12", /* name */
188 FALSE, /* partial_inplace */
189 0, /* src_mask */
190 0x0ffe, /* dst_mask */
191 TRUE), /* pcrel_offset */
192
193 /* A 24-bit absolute relocation suitable for the jump instructions. */
194 HOWTO (R_XSTORMY16_24, /* type */
195 0, /* rightshift */
196 2, /* size (0 = byte, 1 = short, 2 = long) */
197 24, /* bitsize */
198 FALSE, /* pc_relative */
199 0, /* bitpos */
200 complain_overflow_unsigned, /* complain_on_overflow */
201 xstormy16_elf_24_reloc, /* special_function */
202 "R_XSTORMY16_24", /* name */
203 TRUE, /* partial_inplace */
204 0, /* src_mask */
205 0xffff00ff, /* dst_mask */
206 TRUE), /* pcrel_offset */
207
208 /* A 16 bit absolute relocation to a function pointer. */
209 HOWTO (R_XSTORMY16_FPTR16, /* type */
210 0, /* rightshift */
211 1, /* size (0 = byte, 1 = short, 2 = long) */
212 16, /* bitsize */
213 FALSE, /* pc_relative */
214 0, /* bitpos */
215 complain_overflow_bitfield, /* complain_on_overflow */
216 bfd_elf_generic_reloc, /* special_function */
217 "R_XSTORMY16_FPTR16", /* name */
218 FALSE, /* partial_inplace */
219 0, /* src_mask */
220 0xffffffff, /* dst_mask */
221 FALSE), /* pcrel_offset */
222
223 /* Low order 16 bit value of a high memory address. */
224 HOWTO (R_XSTORMY16_LO16, /* type */
225 0, /* rightshift */
226 1, /* size (0 = byte, 1 = short, 2 = long) */
227 16, /* bitsize */
228 FALSE, /* pc_relative */
229 0, /* bitpos */
230 complain_overflow_dont, /* complain_on_overflow */
231 bfd_elf_generic_reloc, /* special_function */
232 "R_XSTORMY16_LO16", /* name */
233 FALSE, /* partial_inplace */
234 0, /* src_mask */
235 0xffff, /* dst_mask */
236 FALSE), /* pcrel_offset */
237
238 /* High order 16 bit value of a high memory address. */
239 HOWTO (R_XSTORMY16_HI16, /* type */
240 16, /* rightshift */
241 1, /* size (0 = byte, 1 = short, 2 = long) */
242 16, /* bitsize */
243 FALSE, /* pc_relative */
244 0, /* bitpos */
245 complain_overflow_dont, /* complain_on_overflow */
246 bfd_elf_generic_reloc, /* special_function */
247 "R_XSTORMY16_HI16", /* name */
248 FALSE, /* partial_inplace */
249 0, /* src_mask */
250 0xffff, /* dst_mask */
251 FALSE), /* pcrel_offset */
252
253 /* A 12 bit absolute relocation. */
254 HOWTO (R_XSTORMY16_12, /* type */
255 0, /* rightshift */
256 1, /* size (0 = byte, 1 = short, 2 = long) */
257 12, /* bitsize */
258 FALSE, /* pc_relative */
259 0, /* bitpos */
260 complain_overflow_signed, /* complain_on_overflow */
261 bfd_elf_generic_reloc, /* special_function */
262 "R_XSTORMY16_12", /* name */
263 FALSE, /* partial_inplace */
264 0x0000, /* src_mask */
265 0x0fff, /* dst_mask */
266 FALSE), /* pcrel_offset */
267 };
268
269 static reloc_howto_type xstormy16_elf_howto_table2 [] =
270 {
271 /* GNU extension to record C++ vtable hierarchy */
272 HOWTO (R_XSTORMY16_GNU_VTINHERIT, /* type */
273 0, /* rightshift */
274 2, /* size (0 = byte, 1 = short, 2 = long) */
275 0, /* bitsize */
276 FALSE, /* pc_relative */
277 0, /* bitpos */
278 complain_overflow_dont, /* complain_on_overflow */
279 NULL, /* special_function */
280 "R_XSTORMY16_GNU_VTINHERIT", /* name */
281 FALSE, /* partial_inplace */
282 0, /* src_mask */
283 0, /* dst_mask */
284 FALSE), /* pcrel_offset */
285
286 /* GNU extension to record C++ vtable member usage */
287 HOWTO (R_XSTORMY16_GNU_VTENTRY, /* type */
288 0, /* rightshift */
289 2, /* size (0 = byte, 1 = short, 2 = long) */
290 0, /* bitsize */
291 FALSE, /* pc_relative */
292 0, /* bitpos */
293 complain_overflow_dont, /* complain_on_overflow */
294 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
295 "R_XSTORMY16_GNU_VTENTRY", /* name */
296 FALSE, /* partial_inplace */
297 0, /* src_mask */
298 0, /* dst_mask */
299 FALSE), /* pcrel_offset */
300
301 };
302
303 /* Map BFD reloc types to XSTORMY16 ELF reloc types. */
304
305 typedef struct xstormy16_reloc_map
306 {
307 bfd_reloc_code_real_type bfd_reloc_val;
308 unsigned int xstormy16_reloc_val;
309 reloc_howto_type * table;
310 } reloc_map;
311
312 static const reloc_map xstormy16_reloc_map [] =
313 {
314 { BFD_RELOC_NONE, R_XSTORMY16_NONE, xstormy16_elf_howto_table },
315 { BFD_RELOC_32, R_XSTORMY16_32, xstormy16_elf_howto_table },
316 { BFD_RELOC_16, R_XSTORMY16_16, xstormy16_elf_howto_table },
317 { BFD_RELOC_8, R_XSTORMY16_8, xstormy16_elf_howto_table },
318 { BFD_RELOC_32_PCREL, R_XSTORMY16_PC32, xstormy16_elf_howto_table },
319 { BFD_RELOC_16_PCREL, R_XSTORMY16_PC16, xstormy16_elf_howto_table },
320 { BFD_RELOC_8_PCREL, R_XSTORMY16_PC8, xstormy16_elf_howto_table },
321 { BFD_RELOC_XSTORMY16_REL_12, R_XSTORMY16_REL_12, xstormy16_elf_howto_table },
322 { BFD_RELOC_XSTORMY16_24, R_XSTORMY16_24, xstormy16_elf_howto_table },
323 { BFD_RELOC_XSTORMY16_FPTR16, R_XSTORMY16_FPTR16, xstormy16_elf_howto_table },
324 { BFD_RELOC_LO16, R_XSTORMY16_LO16, xstormy16_elf_howto_table },
325 { BFD_RELOC_HI16, R_XSTORMY16_HI16, xstormy16_elf_howto_table },
326 { BFD_RELOC_XSTORMY16_12, R_XSTORMY16_12, xstormy16_elf_howto_table },
327 { BFD_RELOC_VTABLE_INHERIT, R_XSTORMY16_GNU_VTINHERIT, xstormy16_elf_howto_table2 },
328 { BFD_RELOC_VTABLE_ENTRY, R_XSTORMY16_GNU_VTENTRY, xstormy16_elf_howto_table2 },
329 };
330
331 static reloc_howto_type *
xstormy16_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)332 xstormy16_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
333 bfd_reloc_code_real_type code)
334 {
335 unsigned int i;
336
337 for (i = ARRAY_SIZE (xstormy16_reloc_map); i--;)
338 {
339 const reloc_map * entry;
340
341 entry = xstormy16_reloc_map + i;
342
343 if (entry->bfd_reloc_val == code)
344 return entry->table + (entry->xstormy16_reloc_val
345 - entry->table[0].type);
346 }
347
348 return NULL;
349 }
350
351 static reloc_howto_type *
xstormy16_reloc_name_lookup(bfd * abfd ATTRIBUTE_UNUSED,const char * r_name)352 xstormy16_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
353 const char *r_name)
354 {
355 unsigned int i;
356
357 for (i = 0;
358 i < (sizeof (xstormy16_elf_howto_table)
359 / sizeof (xstormy16_elf_howto_table[0]));
360 i++)
361 if (xstormy16_elf_howto_table[i].name != NULL
362 && strcasecmp (xstormy16_elf_howto_table[i].name, r_name) == 0)
363 return &xstormy16_elf_howto_table[i];
364
365 for (i = 0;
366 i < (sizeof (xstormy16_elf_howto_table2)
367 / sizeof (xstormy16_elf_howto_table2[0]));
368 i++)
369 if (xstormy16_elf_howto_table2[i].name != NULL
370 && strcasecmp (xstormy16_elf_howto_table2[i].name, r_name) == 0)
371 return &xstormy16_elf_howto_table2[i];
372
373 return NULL;
374 }
375
376 /* Set the howto pointer for an XSTORMY16 ELF reloc. */
377
378 static bfd_boolean
xstormy16_info_to_howto_rela(bfd * abfd,arelent * cache_ptr,Elf_Internal_Rela * dst)379 xstormy16_info_to_howto_rela (bfd * abfd,
380 arelent * cache_ptr,
381 Elf_Internal_Rela * dst)
382 {
383 unsigned int r_type = ELF32_R_TYPE (dst->r_info);
384
385 if (r_type <= (unsigned int) R_XSTORMY16_12)
386 cache_ptr->howto = &xstormy16_elf_howto_table [r_type];
387 else if (r_type - R_XSTORMY16_GNU_VTINHERIT
388 <= ((unsigned int) R_XSTORMY16_GNU_VTENTRY
389 - (unsigned int) R_XSTORMY16_GNU_VTINHERIT))
390 cache_ptr->howto
391 = &xstormy16_elf_howto_table2 [r_type - R_XSTORMY16_GNU_VTINHERIT];
392 else
393 {
394 /* xgettext:c-format */
395 _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
396 abfd, r_type);
397 bfd_set_error (bfd_error_bad_value);
398 return FALSE;
399 }
400 return TRUE;
401 }
402
403 /* We support 16-bit pointers to code above 64k by generating a thunk
404 below 64k containing a JMPF instruction to the final address. We
405 cannot, unfortunately, minimize the number of thunks unless the
406 -relax switch is given, as otherwise we have no idea where the
407 sections will fall in the address space. */
408
409 static bfd_boolean
xstormy16_elf_check_relocs(bfd * abfd,struct bfd_link_info * info,asection * sec,const Elf_Internal_Rela * relocs)410 xstormy16_elf_check_relocs (bfd *abfd,
411 struct bfd_link_info *info,
412 asection *sec,
413 const Elf_Internal_Rela *relocs)
414 {
415 const Elf_Internal_Rela *rel, *relend;
416 struct elf_link_hash_entry **sym_hashes;
417 Elf_Internal_Shdr *symtab_hdr;
418 bfd_vma *local_plt_offsets;
419 asection *splt;
420 bfd *dynobj;
421
422 if (bfd_link_relocatable (info))
423 return TRUE;
424
425 symtab_hdr = &elf_tdata(abfd)->symtab_hdr;
426 sym_hashes = elf_sym_hashes (abfd);
427 local_plt_offsets = elf_local_got_offsets (abfd);
428 dynobj = elf_hash_table(info)->dynobj;
429
430 relend = relocs + sec->reloc_count;
431 for (rel = relocs; rel < relend; ++rel)
432 {
433 unsigned long r_symndx;
434 struct elf_link_hash_entry *h;
435 bfd_vma *offset;
436
437 r_symndx = ELF32_R_SYM (rel->r_info);
438 if (r_symndx < symtab_hdr->sh_info)
439 h = NULL;
440 else
441 {
442 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
443 while (h->root.type == bfd_link_hash_indirect
444 || h->root.type == bfd_link_hash_warning)
445 h = (struct elf_link_hash_entry *) h->root.u.i.link;
446 }
447
448 switch (ELF32_R_TYPE (rel->r_info))
449 {
450 /* This relocation describes a 16-bit pointer to a function.
451 We may need to allocate a thunk in low memory; reserve memory
452 for it now. */
453 case R_XSTORMY16_FPTR16:
454 if (rel->r_addend != 0)
455 {
456 (*info->callbacks->warning)
457 (info, _("non-zero addend in @fptr reloc"), 0,
458 abfd, 0, 0);
459 }
460
461 if (dynobj == NULL)
462 elf_hash_table (info)->dynobj = dynobj = abfd;
463 splt = elf_hash_table (info)->splt;
464 if (splt == NULL)
465 {
466 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
467 | SEC_IN_MEMORY | SEC_LINKER_CREATED
468 | SEC_READONLY | SEC_CODE);
469
470 splt = bfd_make_section_anyway_with_flags (dynobj, ".plt",
471 flags);
472 elf_hash_table (info)->splt = splt;
473 if (splt == NULL
474 || !bfd_set_section_alignment (splt, 1))
475 return FALSE;
476 }
477
478 if (h != NULL)
479 offset = &h->plt.offset;
480 else
481 {
482 if (local_plt_offsets == NULL)
483 {
484 size_t size;
485 unsigned int i;
486
487 size = symtab_hdr->sh_info * sizeof (bfd_vma);
488 local_plt_offsets = bfd_alloc (abfd, size);
489 if (local_plt_offsets == NULL)
490 return FALSE;
491 elf_local_got_offsets (abfd) = local_plt_offsets;
492
493 for (i = 0; i < symtab_hdr->sh_info; i++)
494 local_plt_offsets[i] = (bfd_vma) -1;
495 }
496 offset = &local_plt_offsets[r_symndx];
497 }
498
499 if (*offset == (bfd_vma) -1)
500 {
501 *offset = splt->size;
502 splt->size += 4;
503 }
504 break;
505
506 /* This relocation describes the C++ object vtable hierarchy.
507 Reconstruct it for later use during GC. */
508 case R_XSTORMY16_GNU_VTINHERIT:
509 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
510 return FALSE;
511 break;
512
513 /* This relocation describes which C++ vtable entries are actually
514 used. Record for later use during GC. */
515 case R_XSTORMY16_GNU_VTENTRY:
516 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
517 return FALSE;
518 break;
519 }
520 }
521
522 return TRUE;
523 }
524
525 /* A subroutine of xstormy16_elf_relax_section. If the global symbol H
526 is within the low 64k, remove any entry for it in the plt. */
527
528 struct relax_plt_data
529 {
530 asection *splt;
531 bfd_boolean *again;
532 };
533
534 static bfd_boolean
xstormy16_relax_plt_check(struct elf_link_hash_entry * h,void * xdata)535 xstormy16_relax_plt_check (struct elf_link_hash_entry *h, void * xdata)
536 {
537 struct relax_plt_data *data = (struct relax_plt_data *) xdata;
538
539 if (h->plt.offset != (bfd_vma) -1)
540 {
541 bfd_vma address;
542
543 if (h->root.type == bfd_link_hash_undefined
544 || h->root.type == bfd_link_hash_undefweak)
545 address = 0;
546 else
547 address = (h->root.u.def.section->output_section->vma
548 + h->root.u.def.section->output_offset
549 + h->root.u.def.value);
550
551 if (address <= 0xffff)
552 {
553 h->plt.offset = -1;
554 data->splt->size -= 4;
555 *data->again = TRUE;
556 }
557 }
558
559 return TRUE;
560 }
561
562 /* A subroutine of xstormy16_elf_relax_section. If the global symbol H
563 previously had a plt entry, give it a new entry offset. */
564
565 static bfd_boolean
xstormy16_relax_plt_realloc(struct elf_link_hash_entry * h,void * xdata)566 xstormy16_relax_plt_realloc (struct elf_link_hash_entry *h, void * xdata)
567 {
568 bfd_vma *entry = (bfd_vma *) xdata;
569
570 if (h->plt.offset != (bfd_vma) -1)
571 {
572 h->plt.offset = *entry;
573 *entry += 4;
574 }
575
576 return TRUE;
577 }
578
579 static bfd_boolean
xstormy16_elf_relax_section(bfd * dynobj,asection * splt,struct bfd_link_info * info,bfd_boolean * again)580 xstormy16_elf_relax_section (bfd *dynobj,
581 asection *splt,
582 struct bfd_link_info *info,
583 bfd_boolean *again)
584 {
585 struct relax_plt_data relax_plt_data;
586 bfd *ibfd;
587
588 /* Assume nothing changes. */
589 *again = FALSE;
590
591 if (bfd_link_relocatable (info))
592 return TRUE;
593
594 /* We only relax the .plt section at the moment. */
595 if (dynobj != elf_hash_table (info)->dynobj
596 || strcmp (splt->name, ".plt") != 0)
597 return TRUE;
598
599 /* Quick check for an empty plt. */
600 if (splt->size == 0)
601 return TRUE;
602
603 /* Map across all global symbols; see which ones happen to
604 fall in the low 64k. */
605 relax_plt_data.splt = splt;
606 relax_plt_data.again = again;
607 elf_link_hash_traverse (elf_hash_table (info), xstormy16_relax_plt_check,
608 &relax_plt_data);
609
610 /* Likewise for local symbols, though that's somewhat less convenient
611 as we have to walk the list of input bfds and swap in symbol data. */
612 for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link.next)
613 {
614 bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd);
615 Elf_Internal_Shdr *symtab_hdr;
616 Elf_Internal_Sym *isymbuf = NULL;
617 unsigned int idx;
618
619 if (! local_plt_offsets)
620 continue;
621
622 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
623 if (symtab_hdr->sh_info != 0)
624 {
625 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
626 if (isymbuf == NULL)
627 isymbuf = bfd_elf_get_elf_syms (ibfd, symtab_hdr,
628 symtab_hdr->sh_info, 0,
629 NULL, NULL, NULL);
630 if (isymbuf == NULL)
631 return FALSE;
632 }
633
634 for (idx = 0; idx < symtab_hdr->sh_info; ++idx)
635 {
636 Elf_Internal_Sym *isym;
637 asection *tsec;
638 bfd_vma address;
639
640 if (local_plt_offsets[idx] == (bfd_vma) -1)
641 continue;
642
643 isym = &isymbuf[idx];
644 if (isym->st_shndx == SHN_UNDEF)
645 continue;
646 else if (isym->st_shndx == SHN_ABS)
647 tsec = bfd_abs_section_ptr;
648 else if (isym->st_shndx == SHN_COMMON)
649 tsec = bfd_com_section_ptr;
650 else
651 tsec = bfd_section_from_elf_index (ibfd, isym->st_shndx);
652
653 address = (tsec->output_section->vma
654 + tsec->output_offset
655 + isym->st_value);
656 if (address <= 0xffff)
657 {
658 local_plt_offsets[idx] = -1;
659 splt->size -= 4;
660 *again = TRUE;
661 }
662 }
663
664 if (isymbuf != NULL
665 && symtab_hdr->contents != (unsigned char *) isymbuf)
666 {
667 if (! info->keep_memory)
668 free (isymbuf);
669 else
670 {
671 /* Cache the symbols for elf_link_input_bfd. */
672 symtab_hdr->contents = (unsigned char *) isymbuf;
673 }
674 }
675 }
676
677 /* If we changed anything, walk the symbols again to reallocate
678 .plt entry addresses. */
679 if (*again && splt->size > 0)
680 {
681 bfd_vma entry = 0;
682
683 elf_link_hash_traverse (elf_hash_table (info),
684 xstormy16_relax_plt_realloc, &entry);
685
686 for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link.next)
687 {
688 bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd);
689 unsigned int nlocals = elf_tdata (ibfd)->symtab_hdr.sh_info;
690 unsigned int idx;
691
692 if (! local_plt_offsets)
693 continue;
694
695 for (idx = 0; idx < nlocals; ++idx)
696 if (local_plt_offsets[idx] != (bfd_vma) -1)
697 {
698 local_plt_offsets[idx] = entry;
699 entry += 4;
700 }
701 }
702 }
703
704 return TRUE;
705 }
706
707 static bfd_boolean
xstormy16_elf_always_size_sections(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)708 xstormy16_elf_always_size_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
709 struct bfd_link_info *info)
710 {
711 bfd *dynobj;
712 asection *splt;
713
714 if (bfd_link_relocatable (info))
715 return TRUE;
716
717 dynobj = elf_hash_table (info)->dynobj;
718 if (dynobj == NULL)
719 return TRUE;
720
721 splt = elf_hash_table (info)->splt;
722 BFD_ASSERT (splt != NULL);
723
724 splt->contents = bfd_zalloc (dynobj, splt->size);
725 if (splt->contents == NULL)
726 return FALSE;
727
728 return TRUE;
729 }
730
731 /* Relocate an XSTORMY16 ELF section.
732
733 The RELOCATE_SECTION function is called by the new ELF backend linker
734 to handle the relocations for a section.
735
736 The relocs are always passed as Rela structures; if the section
737 actually uses Rel structures, the r_addend field will always be
738 zero.
739
740 This function is responsible for adjusting the section contents as
741 necessary, and (if using Rela relocs and generating a relocatable
742 output file) adjusting the reloc addend as necessary.
743
744 This function does not have to worry about setting the reloc
745 address or the reloc symbol index.
746
747 LOCAL_SYMS is a pointer to the swapped in local symbols.
748
749 LOCAL_SECTIONS is an array giving the section in the input file
750 corresponding to the st_shndx field of each local symbol.
751
752 The global hash table entry for the global symbols can be found
753 via elf_sym_hashes (input_bfd).
754
755 When generating relocatable output, this function must handle
756 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
757 going to be the section symbol corresponding to the output
758 section, which means that the addend must be adjusted
759 accordingly. */
760
761 static bfd_boolean
xstormy16_elf_relocate_section(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * relocs,Elf_Internal_Sym * local_syms,asection ** local_sections)762 xstormy16_elf_relocate_section (bfd * output_bfd ATTRIBUTE_UNUSED,
763 struct bfd_link_info * info,
764 bfd * input_bfd,
765 asection * input_section,
766 bfd_byte * contents,
767 Elf_Internal_Rela * relocs,
768 Elf_Internal_Sym * local_syms,
769 asection ** local_sections)
770 {
771 Elf_Internal_Shdr * symtab_hdr;
772 struct elf_link_hash_entry ** sym_hashes;
773 Elf_Internal_Rela * rel;
774 Elf_Internal_Rela * relend;
775 asection *splt;
776
777 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
778 sym_hashes = elf_sym_hashes (input_bfd);
779 relend = relocs + input_section->reloc_count;
780
781 splt = elf_hash_table (info)->splt;
782
783 for (rel = relocs; rel < relend; rel ++)
784 {
785 reloc_howto_type * howto;
786 unsigned long r_symndx;
787 Elf_Internal_Sym * sym;
788 asection * sec;
789 struct elf_link_hash_entry * h;
790 bfd_vma relocation;
791 bfd_reloc_status_type r;
792 const char * name = NULL;
793 int r_type;
794
795 r_type = ELF32_R_TYPE (rel->r_info);
796
797 if ( r_type == R_XSTORMY16_GNU_VTINHERIT
798 || r_type == R_XSTORMY16_GNU_VTENTRY)
799 continue;
800
801 r_symndx = ELF32_R_SYM (rel->r_info);
802 howto = xstormy16_elf_howto_table + ELF32_R_TYPE (rel->r_info);
803 h = NULL;
804 sym = NULL;
805 sec = NULL;
806
807 if (r_symndx < symtab_hdr->sh_info)
808 {
809 sym = local_syms + r_symndx;
810 sec = local_sections [r_symndx];
811 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
812 }
813 else
814 {
815 bfd_boolean unresolved_reloc, warned, ignored;
816
817 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
818 r_symndx, symtab_hdr, sym_hashes,
819 h, sec, relocation,
820 unresolved_reloc, warned, ignored);
821 }
822
823 if (sec != NULL && discarded_section (sec))
824 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
825 rel, 1, relend, howto, 0, contents);
826
827 if (bfd_link_relocatable (info))
828 continue;
829
830 if (h != NULL)
831 name = h->root.root.string;
832 else
833 {
834 name = (bfd_elf_string_from_elf_section
835 (input_bfd, symtab_hdr->sh_link, sym->st_name));
836 if (name == NULL || *name == '\0')
837 name = bfd_section_name (sec);
838 }
839
840 switch (ELF32_R_TYPE (rel->r_info))
841 {
842 case R_XSTORMY16_24:
843 {
844 bfd_vma reloc = relocation + rel->r_addend;
845 unsigned int x;
846
847 x = bfd_get_32 (input_bfd, contents + rel->r_offset);
848 x &= 0x0000ff00;
849 x |= reloc & 0xff;
850 x |= (reloc << 8) & 0xffff0000;
851 bfd_put_32 (input_bfd, x, contents + rel->r_offset);
852
853 if (reloc & ~0xffffff)
854 r = bfd_reloc_overflow;
855 else
856 r = bfd_reloc_ok;
857 break;
858 }
859
860 case R_XSTORMY16_FPTR16:
861 {
862 bfd_vma *plt_offset;
863
864 if (h != NULL)
865 plt_offset = &h->plt.offset;
866 else
867 plt_offset = elf_local_got_offsets (input_bfd) + r_symndx;
868
869 if (relocation <= 0xffff)
870 {
871 /* If the symbol is in range for a 16-bit address, we should
872 have deallocated the plt entry in relax_section. */
873 BFD_ASSERT (*plt_offset == (bfd_vma) -1);
874 }
875 else
876 {
877 /* If the symbol is out of range for a 16-bit address,
878 we must have allocated a plt entry. */
879 BFD_ASSERT (*plt_offset != (bfd_vma) -1);
880
881 /* If this is the first time we've processed this symbol,
882 fill in the plt entry with the correct symbol address. */
883 if ((*plt_offset & 1) == 0)
884 {
885 unsigned int x;
886
887 x = 0x00000200; /* jmpf */
888 x |= relocation & 0xff;
889 x |= (relocation << 8) & 0xffff0000;
890 bfd_put_32 (input_bfd, x, splt->contents + *plt_offset);
891 *plt_offset |= 1;
892 }
893
894 relocation = (splt->output_section->vma
895 + splt->output_offset
896 + (*plt_offset & -2));
897 }
898 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
899 contents, rel->r_offset,
900 relocation, 0);
901 break;
902 }
903
904 default:
905 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
906 contents, rel->r_offset,
907 relocation, rel->r_addend);
908 break;
909 }
910
911 if (r != bfd_reloc_ok)
912 {
913 const char * msg = NULL;
914
915 switch (r)
916 {
917 case bfd_reloc_overflow:
918 (*info->callbacks->reloc_overflow)
919 (info, (h ? &h->root : NULL), name, howto->name,
920 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
921 break;
922
923 case bfd_reloc_undefined:
924 (*info->callbacks->undefined_symbol)
925 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
926 break;
927
928 case bfd_reloc_outofrange:
929 msg = _("internal error: out of range error");
930 break;
931
932 case bfd_reloc_notsupported:
933 msg = _("internal error: unsupported relocation error");
934 break;
935
936 case bfd_reloc_dangerous:
937 msg = _("internal error: dangerous relocation");
938 break;
939
940 default:
941 msg = _("internal error: unknown error");
942 break;
943 }
944
945 if (msg)
946 (*info->callbacks->warning) (info, msg, name, input_bfd,
947 input_section, rel->r_offset);
948 }
949 }
950
951 return TRUE;
952 }
953
954 /* This must exist if dynobj is ever set. */
955
956 static bfd_boolean
xstormy16_elf_finish_dynamic_sections(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)957 xstormy16_elf_finish_dynamic_sections (bfd *abfd ATTRIBUTE_UNUSED,
958 struct bfd_link_info *info)
959 {
960 bfd *dynobj = elf_hash_table (info)->dynobj;
961 asection *splt = elf_hash_table (info)->splt;
962
963 /* As an extra sanity check, verify that all plt entries have
964 been filled in. */
965
966 if (dynobj != NULL && splt != NULL)
967 {
968 bfd_byte *contents = splt->contents;
969 unsigned int i, size = splt->size;
970
971 for (i = 0; i < size; i += 4)
972 {
973 unsigned int x = bfd_get_32 (dynobj, contents + i);
974
975 BFD_ASSERT (x != 0);
976 }
977 }
978
979 return TRUE;
980 }
981
982 /* Return the section that should be marked against GC for a given
983 relocation. */
984
985 static asection *
xstormy16_elf_gc_mark_hook(asection * sec,struct bfd_link_info * info,Elf_Internal_Rela * rel,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)986 xstormy16_elf_gc_mark_hook (asection *sec,
987 struct bfd_link_info *info,
988 Elf_Internal_Rela *rel,
989 struct elf_link_hash_entry *h,
990 Elf_Internal_Sym *sym)
991 {
992 if (h != NULL)
993 switch (ELF32_R_TYPE (rel->r_info))
994 {
995 case R_XSTORMY16_GNU_VTINHERIT:
996 case R_XSTORMY16_GNU_VTENTRY:
997 return NULL;
998 }
999
1000 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1001 }
1002
1003 #define ELF_ARCH bfd_arch_xstormy16
1004 #define ELF_MACHINE_CODE EM_XSTORMY16
1005 #define ELF_MAXPAGESIZE 0x100
1006
1007 #define TARGET_LITTLE_SYM xstormy16_elf32_vec
1008 #define TARGET_LITTLE_NAME "elf32-xstormy16"
1009
1010 #define elf_info_to_howto_rel NULL
1011 #define elf_info_to_howto xstormy16_info_to_howto_rela
1012 #define elf_backend_relocate_section xstormy16_elf_relocate_section
1013 #define elf_backend_gc_mark_hook xstormy16_elf_gc_mark_hook
1014 #define elf_backend_check_relocs xstormy16_elf_check_relocs
1015 #define elf_backend_always_size_sections \
1016 xstormy16_elf_always_size_sections
1017 #define elf_backend_omit_section_dynsym \
1018 _bfd_elf_omit_section_dynsym_all
1019 #define elf_backend_finish_dynamic_sections \
1020 xstormy16_elf_finish_dynamic_sections
1021
1022 #define elf_backend_can_gc_sections 1
1023 #define elf_backend_rela_normal 1
1024
1025 #define bfd_elf32_bfd_reloc_type_lookup xstormy16_reloc_type_lookup
1026 #define bfd_elf32_bfd_reloc_name_lookup \
1027 xstormy16_reloc_name_lookup
1028 #define bfd_elf32_bfd_relax_section xstormy16_elf_relax_section
1029
1030 #include "elf32-target.h"
1031