1 /* Zilog (e)Z80-specific support for 32-bit ELF
2 Copyright (C) 1999-2023 Free Software Foundation, Inc.
3 (Heavily copied from the S12Z port by Sergey Belyashov (sergey.belyashov@gmail.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 "bfdlink.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
27
28 #include "elf/z80.h"
29
30 /* All users of this file have bfd_octets_per_byte (abfd, sec) == 1. */
31 #define OCTETS_PER_BYTE(ABFD, SEC) 1
32
33 typedef const struct {
34 bfd_reloc_code_real_type r_type;
35 reloc_howto_type howto;
36 } bfd_howto_type;
37
38 #define BFD_EMPTY_HOWTO(rt,x) {rt, EMPTY_HOWTO(x)}
39 #define BFD_HOWTO(rt,a,b,c,d,e,f,g,h,i,j,k,l,m) {rt, HOWTO(a,b,c,d,e,f,g,h,i,j,k,l,m)}
40
41 static bfd_reloc_status_type
42 z80_elf_16_be_reloc (bfd *abfd, arelent *reloc_entry, asymbol *symbol,
43 void *data, asection *input_section, bfd *output_bfd,
44 char **error_message);
45
46 static const
47 bfd_howto_type elf_z80_howto_table[] =
48 {
49 /* This reloc does nothing. */
50 BFD_HOWTO (BFD_RELOC_NONE,
51 R_Z80_NONE, /* type */
52 0, /* rightshift */
53 0, /* size */
54 0, /* bitsize */
55 false, /* pc_relative */
56 0, /* bitpos */
57 complain_overflow_dont,/* complain_on_overflow */
58 bfd_elf_generic_reloc, /* special_function */
59 "R_NONE", /* name */
60 false, /* partial_inplace */
61 0, /* src_mask */
62 0, /* dst_mask */
63 false), /* pcrel_offset */
64
65 /* A 8 bit relocation */
66 BFD_HOWTO (BFD_RELOC_8,
67 R_Z80_8, /* type */
68 0, /* rightshift */
69 1, /* size */
70 8, /* bitsize */
71 false, /* pc_relative */
72 0, /* bitpos */
73 complain_overflow_bitfield, /* complain_on_overflow */
74 bfd_elf_generic_reloc, /* special_function */
75 "r_imm8", /* name */
76 false, /* partial_inplace */
77 0x00, /* src_mask */
78 0xff, /* dst_mask */
79 false), /* pcrel_offset */
80
81 /* A 8 bit index register displacement relocation */
82 BFD_HOWTO (BFD_RELOC_Z80_DISP8,
83 R_Z80_8_DIS, /* type */
84 0, /* rightshift */
85 1, /* size */
86 8, /* bitsize */
87 false, /* pc_relative */
88 0, /* bitpos */
89 complain_overflow_signed, /* complain_on_overflow */
90 bfd_elf_generic_reloc, /* special_function */
91 "r_off", /* name */
92 false, /* partial_inplace */
93 0x00, /* src_mask */
94 0xff, /* dst_mask */
95 false), /* pcrel_offset */
96
97 /* A 8 bit PC-rel relocation */
98 BFD_HOWTO (BFD_RELOC_8_PCREL,
99 R_Z80_8_PCREL, /* type */
100 0, /* rightshift */
101 1, /* size */
102 8, /* bitsize */
103 true, /* pc_relative */
104 0, /* bitpos */
105 complain_overflow_signed, /* complain_on_overflow */
106 bfd_elf_generic_reloc, /* special_function */
107 "r_jr", /* name */
108 false, /* partial_inplace */
109 0x00, /* src_mask */
110 0xff, /* dst_mask */
111 true), /* pcrel_offset */
112
113 /* An 16 bit absolute relocation */
114 BFD_HOWTO (BFD_RELOC_16,
115 R_Z80_16, /* type */
116 0, /* rightshift */
117 2, /* size */
118 16, /* bitsize */
119 false, /* pc_relative */
120 0, /* bitpos */
121 complain_overflow_bitfield, /* complain_on_overflow */
122 bfd_elf_generic_reloc, /* special_function */
123 "r_imm16", /* name */
124 false, /* partial_inplace */
125 0x00000000, /* src_mask */
126 0x0000ffff, /* dst_mask */
127 false), /* pcrel_offset */
128
129 /* A 24 bit absolute relocation emitted by ADL mode operands */
130 BFD_HOWTO (BFD_RELOC_24,
131 R_Z80_24, /* type */
132 0, /* rightshift */
133 3, /* size */
134 24, /* bitsize */
135 false, /* pc_relative */
136 0, /* bitpos */
137 complain_overflow_bitfield, /* complain_on_overflow */
138 bfd_elf_generic_reloc, /* special_function */
139 "r_imm24", /* name */
140 false, /* partial_inplace */
141 0x00000000, /* src_mask */
142 0x00ffffff, /* dst_mask */
143 false), /* pcrel_offset */
144
145 BFD_HOWTO (BFD_RELOC_32,
146 R_Z80_32, /* type */
147 0, /* rightshift */
148 4, /* size */
149 32, /* bitsize */
150 false, /* pc_relative */
151 0, /* bitpos */
152 complain_overflow_dont,/* complain_on_overflow */
153 bfd_elf_generic_reloc, /* special_function */
154 "r_imm32", /* name */
155 false, /* partial_inplace */
156 0x00000000, /* src_mask */
157 0xffffffff, /* dst_mask */
158 false), /* pcrel_offset */
159
160 /* First (lowest) 8 bits of multibyte relocation */
161 BFD_HOWTO (BFD_RELOC_Z80_BYTE0,
162 R_Z80_BYTE0, /* type */
163 0, /* rightshift */
164 1, /* size */
165 32, /* bitsize */
166 false, /* pc_relative */
167 0, /* bitpos */
168 complain_overflow_dont,/* complain_on_overflow */
169 bfd_elf_generic_reloc, /* special_function */
170 "r_byte0", /* name */
171 false, /* partial_inplace */
172 0, /* src_mask */
173 0xff, /* dst_mask */
174 false), /* pcrel_offset */
175
176 /* Second 8 bits of multibyte relocation */
177 BFD_HOWTO (BFD_RELOC_Z80_BYTE1,
178 R_Z80_BYTE1, /* type */
179 8, /* rightshift */
180 1, /* size */
181 32, /* bitsize */
182 false, /* pc_relative */
183 0, /* bitpos */
184 complain_overflow_dont,/* complain_on_overflow */
185 bfd_elf_generic_reloc, /* special_function */
186 "r_byte1", /* name */
187 false, /* partial_inplace */
188 0, /* src_mask */
189 0xff, /* dst_mask */
190 false), /* pcrel_offset */
191
192 /* Third 8 bits of multibyte relocation */
193 BFD_HOWTO (BFD_RELOC_Z80_BYTE2,
194 R_Z80_BYTE2, /* type */
195 16, /* rightshift */
196 1, /* size */
197 32, /* bitsize */
198 false, /* pc_relative */
199 0, /* bitpos */
200 complain_overflow_dont,/* complain_on_overflow */
201 bfd_elf_generic_reloc, /* special_function */
202 "r_byte2", /* name */
203 false, /* partial_inplace */
204 0, /* src_mask */
205 0xff, /* dst_mask */
206 false), /* pcrel_offset */
207
208 /* Fourth (highest) 8 bits of multibyte relocation */
209 BFD_HOWTO (BFD_RELOC_Z80_BYTE3,
210 R_Z80_BYTE3, /* type */
211 24, /* rightshift */
212 1, /* size */
213 32, /* bitsize */
214 false, /* pc_relative */
215 0, /* bitpos */
216 complain_overflow_dont,/* complain_on_overflow */
217 bfd_elf_generic_reloc, /* special_function */
218 "r_byte3", /* name */
219 false, /* partial_inplace */
220 0, /* src_mask */
221 0xff, /* dst_mask */
222 false), /* pcrel_offset */
223
224 /* An 16 bit absolute relocation of lower word of multibyte value */
225 BFD_HOWTO (BFD_RELOC_Z80_WORD0,
226 R_Z80_WORD0, /* type */
227 0, /* rightshift */
228 2, /* size */
229 32, /* bitsize */
230 false, /* pc_relative */
231 0, /* bitpos */
232 complain_overflow_dont,/* complain_on_overflow */
233 bfd_elf_generic_reloc, /* special_function */
234 "r_word0", /* name */
235 false, /* partial_inplace */
236 0, /* src_mask */
237 0xffff, /* dst_mask */
238 false), /* pcrel_offset */
239
240 /* An 16 bit absolute relocation of higher word of multibyte value */
241 BFD_HOWTO (BFD_RELOC_Z80_WORD1,
242 R_Z80_WORD1, /* type */
243 16, /* rightshift */
244 2, /* size */
245 32, /* bitsize */
246 false, /* pc_relative */
247 0, /* bitpos */
248 complain_overflow_dont,/* complain_on_overflow */
249 bfd_elf_generic_reloc, /* special_function */
250 "r_word1", /* name */
251 false, /* partial_inplace */
252 0, /* src_mask */
253 0xffff, /* dst_mask */
254 false), /* pcrel_offset */
255
256 /* An 16 bit big endian absolute relocation */
257 BFD_HOWTO (BFD_RELOC_Z80_16_BE,
258 R_Z80_16_BE, /* type */
259 0, /* rightshift */
260 2, /* size */
261 16, /* bitsize */
262 false, /* pc_relative */
263 0, /* bitpos */
264 complain_overflow_bitfield, /* complain_on_overflow */
265 z80_elf_16_be_reloc, /* special_function */
266 "r_imm16be", /* name */
267 false, /* partial_inplace */
268 0x00000000, /* src_mask */
269 0x0000ffff, /* dst_mask */
270 false), /* pcrel_offset */
271 };
272
273 static reloc_howto_type *
274 z80_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
275 bfd_reloc_code_real_type code)
276 {
277 enum
278 {
279 table_size = sizeof (elf_z80_howto_table) / sizeof (elf_z80_howto_table[0])
280 };
281 unsigned int i;
282
283 for (i = 0; i < table_size; i++)
284 {
285 if (elf_z80_howto_table[i].r_type == code)
286 return &elf_z80_howto_table[i].howto;
287 }
288
289 printf ("%s:%d Not found BFD reloc type %d\n", __FILE__, __LINE__, code);
290
291 return NULL;
292 }
293
294 static reloc_howto_type *
295 z80_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name)
296 {
297 enum
298 {
299 table_size = sizeof (elf_z80_howto_table) / sizeof (elf_z80_howto_table[0])
300 };
301 unsigned int i;
302
303 for (i = 0; i < table_size; i++)
304 {
305 if (elf_z80_howto_table[i].howto.name != NULL
306 && strcasecmp (elf_z80_howto_table[i].howto.name, r_name) == 0)
307 return &elf_z80_howto_table[i].howto;
308 }
309
310 printf ("%s:%d Not found ELF reloc name `%s'\n", __FILE__, __LINE__, r_name);
311
312 return NULL;
313 }
314
315 static reloc_howto_type *
316 z80_rtype_to_howto (bfd *abfd, unsigned r_type)
317 {
318 enum
319 {
320 table_size = sizeof (elf_z80_howto_table) / sizeof (elf_z80_howto_table[0])
321 };
322 unsigned int i;
323
324 for (i = 0; i < table_size; i++)
325 {
326 if (elf_z80_howto_table[i].howto.type == r_type)
327 return &elf_z80_howto_table[i].howto;
328 }
329
330 /* xgettext:c-format */
331 _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
332 abfd, r_type);
333 return NULL;
334 }
335
336 /* Set the howto pointer for an z80 ELF reloc. */
337
338 static bool
339 z80_info_to_howto_rela (bfd *abfd, arelent *cache_ptr, Elf_Internal_Rela *dst)
340 {
341 unsigned int r_type = ELF32_R_TYPE (dst->r_info);
342 reloc_howto_type *howto = z80_rtype_to_howto (abfd, r_type);
343 if (howto != NULL)
344 {
345 cache_ptr->howto = howto;
346 return true;
347 }
348 bfd_set_error (bfd_error_bad_value);
349 return false;
350 }
351
352 static bfd_reloc_status_type
353 z80_elf_final_link_relocate (unsigned long r_type,
354 bfd *input_bfd,
355 bfd *output_bfd ATTRIBUTE_UNUSED,
356 asection *input_section ATTRIBUTE_UNUSED,
357 bfd_byte *contents,
358 bfd_vma offset,
359 bfd_vma value,
360 bfd_vma addend,
361 struct bfd_link_info *info ATTRIBUTE_UNUSED,
362 asection *sym_sec ATTRIBUTE_UNUSED,
363 int is_local ATTRIBUTE_UNUSED)
364 {
365 bool r;
366 reloc_howto_type *howto;
367
368 switch (r_type)
369 {
370 case R_Z80_16_BE:
371 value += addend;
372 bfd_put_8 (input_bfd, value >> 8, contents + offset + 0);
373 bfd_put_8 (input_bfd, value >> 0, contents + offset + 1);
374 return bfd_reloc_ok;
375 }
376
377 howto = z80_rtype_to_howto (input_bfd, r_type);
378 if (howto == NULL)
379 return bfd_reloc_notsupported;
380
381 r = _bfd_final_link_relocate (howto, input_bfd, input_section, contents,
382 offset, value, addend);
383 return r ? bfd_reloc_ok : bfd_reloc_notsupported;
384 }
385
386 static int
387 z80_elf_relocate_section (bfd *output_bfd,
388 struct bfd_link_info *info,
389 bfd *input_bfd,
390 asection *input_section,
391 bfd_byte *contents,
392 Elf_Internal_Rela *relocs,
393 Elf_Internal_Sym *local_syms,
394 asection **local_sections)
395 {
396 Elf_Internal_Shdr *symtab_hdr;
397 struct elf_link_hash_entry **sym_hashes;
398 Elf_Internal_Rela *rel, *relend;
399
400 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
401 sym_hashes = elf_sym_hashes (input_bfd);
402
403 rel = relocs;
404 relend = relocs + input_section->reloc_count;
405 for (; rel < relend; rel++)
406 {
407 unsigned int r_type;
408 unsigned long r_symndx;
409 Elf_Internal_Sym *sym;
410 asection *sec;
411 struct elf_link_hash_entry *h;
412 bfd_vma relocation;
413
414 /* This is a final link. */
415 r_symndx = ELF32_R_SYM (rel->r_info);
416 r_type = ELF32_R_TYPE (rel->r_info);
417 h = NULL;
418 sym = NULL;
419 sec = NULL;
420 if (r_symndx < symtab_hdr->sh_info)
421 {
422 sym = local_syms + r_symndx;
423 sec = local_sections[r_symndx];
424 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
425 }
426 else
427 {
428 bool unresolved_reloc, warned, ignored;
429
430 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
431 r_symndx, symtab_hdr, sym_hashes,
432 h, sec, relocation,
433 unresolved_reloc, warned, ignored);
434 }
435
436 if (sec != NULL && discarded_section (sec))
437 {
438 /* For relocs against symbols from removed linkonce sections,
439 or sections discarded by a linker script, we just want the
440 section contents cleared. Avoid any special processing. */
441 reloc_howto_type *howto;
442 howto = z80_rtype_to_howto (input_bfd, r_type);
443 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
444 rel, 1, relend, howto, 0, contents);
445 }
446
447 if (bfd_link_relocatable (info))
448 continue;
449
450
451 z80_elf_final_link_relocate (r_type, input_bfd, output_bfd,
452 input_section,
453 contents, rel->r_offset,
454 relocation, rel->r_addend,
455 info, sec, h == NULL);
456 }
457
458 return true;
459 }
460
461 /* The final processing done just before writing out a Z80 ELF object
462 file. This gets the Z80 architecture right based on the machine
463 number. */
464
465 static bool
466 z80_elf_final_write_processing (bfd *abfd)
467 {
468 unsigned long val = bfd_get_mach (abfd);
469
470 switch (val)
471 {
472 default:
473 _bfd_error_handler (_("%pB: unsupported bfd mach %#lx"),
474 abfd, val);
475 /* fall through */
476 case bfd_mach_z80:
477 case bfd_mach_z80full:
478 case bfd_mach_z80strict:
479 val = EF_Z80_MACH_Z80;
480 break;
481 case bfd_mach_gbz80:
482 val = EF_Z80_MACH_GBZ80;
483 break;
484 case bfd_mach_z80n:
485 val = EF_Z80_MACH_Z80N;
486 break;
487 case bfd_mach_z180:
488 val = EF_Z80_MACH_Z180;
489 break;
490 case bfd_mach_ez80_z80:
491 val = EF_Z80_MACH_EZ80_Z80;
492 break;
493 case bfd_mach_ez80_adl:
494 val = EF_Z80_MACH_EZ80_ADL;
495 break;
496 case bfd_mach_r800:
497 val = EF_Z80_MACH_R800;
498 break;
499 }
500 elf_elfheader (abfd)->e_machine = EM_Z80;
501 elf_elfheader (abfd)->e_flags &= ~EF_Z80_MACH_MSK;
502 elf_elfheader (abfd)->e_flags |= val;
503 return _bfd_elf_final_write_processing (abfd);
504 }
505
506 /* Set the right machine number. */
507 static bool
508 z80_elf_object_p (bfd *abfd)
509 {
510 unsigned int mach;
511
512 if (elf_elfheader (abfd)->e_machine == EM_Z80)
513 {
514 int e_mach = elf_elfheader (abfd)->e_flags & EF_Z80_MACH_MSK;
515 switch (e_mach)
516 {
517 default:
518 _bfd_error_handler (_("%pB: unsupported mach %#x"),
519 abfd, e_mach);
520 /* fall through */
521 case EF_Z80_MACH_Z80:
522 mach = bfd_mach_z80;
523 break;
524 case EF_Z80_MACH_GBZ80:
525 mach = bfd_mach_gbz80;
526 break;
527 case EF_Z80_MACH_Z180:
528 mach = bfd_mach_z180;
529 break;
530 case EF_Z80_MACH_EZ80_Z80:
531 mach = bfd_mach_ez80_z80;
532 break;
533 case EF_Z80_MACH_EZ80_ADL:
534 mach = bfd_mach_ez80_adl;
535 break;
536 case EF_Z80_MACH_R800:
537 mach = bfd_mach_r800;
538 break;
539 case EF_Z80_MACH_Z80N:
540 mach = bfd_mach_z80n;
541 break;
542 }
543 }
544 else
545 {
546 _bfd_error_handler (_("%pB: unsupported arch %#x"),
547 abfd, elf_elfheader (abfd)->e_machine);
548 mach = bfd_mach_z80;
549 }
550 return bfd_default_set_arch_mach (abfd, bfd_arch_z80, mach);
551 }
552
553 static bool
554 z80_is_local_label_name (bfd * abfd ATTRIBUTE_UNUSED,
555 const char * name)
556 {
557 return (name[0] == '.' && name[1] == 'L') ||
558 _bfd_elf_is_local_label_name (abfd, name);
559 }
560
561 static bfd_reloc_status_type
562 z80_elf_16_be_reloc (bfd *abfd,
563 arelent *reloc_entry,
564 asymbol *symbol,
565 void *data,
566 asection *input_section,
567 bfd *output_bfd,
568 char **error_message)
569 {
570 bfd_vma val;
571 long x;
572 bfd_size_type octets = (reloc_entry->address
573 * OCTETS_PER_BYTE (abfd, input_section));
574
575 /* If this is a relocatable link (output_bfd test tells us), just
576 call the generic function. Any adjustment will be done at final
577 link time. */
578 if (output_bfd != NULL)
579 return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data,
580 input_section, output_bfd, error_message);
581
582 /* Get symbol value. */
583 val = 0;
584 if (!bfd_is_com_section (symbol->section))
585 val = symbol->value;
586 val += symbol->section->output_offset + input_section->output_offset;
587 if (symbol->section->output_section)
588 val += symbol->section->output_section->vma;
589
590 val += reloc_entry->addend;
591 if (reloc_entry->howto->partial_inplace)
592 {
593 x = bfd_get_8 (abfd, (bfd_byte *) data + octets + 0) * 0x100;
594 x += bfd_get_8 (abfd, (bfd_byte *) data + octets + 1);
595 x &= ~reloc_entry->howto->src_mask;
596 }
597 else
598 x = 0;
599
600 x |= val & reloc_entry->howto->dst_mask;
601 if (x < -0x8000 || x >= 0x10000)
602 return bfd_reloc_outofrange;
603
604 bfd_put_8 (abfd, x >> 8, (bfd_byte *) data + octets + 0);
605 bfd_put_8 (abfd, x >> 0, (bfd_byte *) data + octets + 1);
606 return bfd_reloc_ok;
607 }
608
609 #define ELF_ARCH bfd_arch_z80
610 #define ELF_MACHINE_CODE EM_Z80
611 #define ELF_MAXPAGESIZE 0x10000
612
613 #define TARGET_LITTLE_SYM z80_elf32_vec
614 #define TARGET_LITTLE_NAME "elf32-z80"
615
616 #define elf_backend_can_refcount 1
617 #define elf_backend_can_gc_sections 1
618 #define elf_backend_stack_align 1
619 #define elf_backend_rela_normal 1
620
621 #define elf_info_to_howto z80_info_to_howto_rela
622 #define elf_info_to_howto_rel z80_info_to_howto_rela
623
624 #define elf_backend_final_write_processing z80_elf_final_write_processing
625 #define elf_backend_object_p z80_elf_object_p
626 #define elf_backend_relocate_section z80_elf_relocate_section
627
628 #define bfd_elf32_bfd_reloc_type_lookup z80_reloc_type_lookup
629 #define bfd_elf32_bfd_reloc_name_lookup z80_reloc_name_lookup
630 #define bfd_elf32_bfd_is_local_label_name z80_is_local_label_name
631
632 #include "elf32-target.h"