88f491f9143329a92041956d7929c1472039857c
[deliverable/binutils-gdb.git] / bfd / elfnn-riscv.c
1 /* RISC-V-specific support for NN-bit ELF.
2 Copyright (C) 2011-2018 Free Software Foundation, Inc.
3
4 Contributed by Andrew Waterman (andrew@sifive.com).
5 Based on TILE-Gx and MIPS targets.
6
7 This file is part of BFD, the Binary File Descriptor library.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program; see the file COPYING3. If not,
21 see <http://www.gnu.org/licenses/>. */
22
23 /* This file handles RISC-V ELF targets. */
24
25 #include "sysdep.h"
26 #include "bfd.h"
27 #include "libbfd.h"
28 #include "bfdlink.h"
29 #include "genlink.h"
30 #include "elf-bfd.h"
31 #include "elfxx-riscv.h"
32 #include "elf/riscv.h"
33 #include "opcode/riscv.h"
34
35 /* Internal relocations used exclusively by the relaxation pass. */
36 #define R_RISCV_DELETE (R_RISCV_max + 1)
37
38 #define ARCH_SIZE NN
39
40 #define MINUS_ONE ((bfd_vma)0 - 1)
41
42 #define RISCV_ELF_LOG_WORD_BYTES (ARCH_SIZE == 32 ? 2 : 3)
43
44 #define RISCV_ELF_WORD_BYTES (1 << RISCV_ELF_LOG_WORD_BYTES)
45
46 /* The name of the dynamic interpreter. This is put in the .interp
47 section. */
48
49 #define ELF64_DYNAMIC_INTERPRETER "/lib/ld.so.1"
50 #define ELF32_DYNAMIC_INTERPRETER "/lib32/ld.so.1"
51
52 #define ELF_ARCH bfd_arch_riscv
53 #define ELF_TARGET_ID RISCV_ELF_DATA
54 #define ELF_MACHINE_CODE EM_RISCV
55 #define ELF_MAXPAGESIZE 0x1000
56 #define ELF_COMMONPAGESIZE 0x1000
57
58 /* RISC-V ELF linker hash entry. */
59
60 struct riscv_elf_link_hash_entry
61 {
62 struct elf_link_hash_entry elf;
63
64 /* Track dynamic relocs copied for this symbol. */
65 struct elf_dyn_relocs *dyn_relocs;
66
67 #define GOT_UNKNOWN 0
68 #define GOT_NORMAL 1
69 #define GOT_TLS_GD 2
70 #define GOT_TLS_IE 4
71 #define GOT_TLS_LE 8
72 char tls_type;
73 };
74
75 #define riscv_elf_hash_entry(ent) \
76 ((struct riscv_elf_link_hash_entry *)(ent))
77
78 struct _bfd_riscv_elf_obj_tdata
79 {
80 struct elf_obj_tdata root;
81
82 /* tls_type for each local got entry. */
83 char *local_got_tls_type;
84 };
85
86 #define _bfd_riscv_elf_tdata(abfd) \
87 ((struct _bfd_riscv_elf_obj_tdata *) (abfd)->tdata.any)
88
89 #define _bfd_riscv_elf_local_got_tls_type(abfd) \
90 (_bfd_riscv_elf_tdata (abfd)->local_got_tls_type)
91
92 #define _bfd_riscv_elf_tls_type(abfd, h, symndx) \
93 (*((h) != NULL ? &riscv_elf_hash_entry (h)->tls_type \
94 : &_bfd_riscv_elf_local_got_tls_type (abfd) [symndx]))
95
96 #define is_riscv_elf(bfd) \
97 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
98 && elf_tdata (bfd) != NULL \
99 && elf_object_id (bfd) == RISCV_ELF_DATA)
100
101 #include "elf/common.h"
102 #include "elf/internal.h"
103
104 struct riscv_elf_link_hash_table
105 {
106 struct elf_link_hash_table elf;
107
108 /* Short-cuts to get to dynamic linker sections. */
109 asection *sdyntdata;
110
111 /* Small local sym to section mapping cache. */
112 struct sym_cache sym_cache;
113
114 /* The max alignment of output sections. */
115 bfd_vma max_alignment;
116 };
117
118
119 /* Get the RISC-V ELF linker hash table from a link_info structure. */
120 #define riscv_elf_hash_table(p) \
121 (elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) \
122 == RISCV_ELF_DATA ? ((struct riscv_elf_link_hash_table *) ((p)->hash)) : NULL)
123
124 static bfd_boolean
125 riscv_info_to_howto_rela (bfd *abfd,
126 arelent *cache_ptr,
127 Elf_Internal_Rela *dst)
128 {
129 cache_ptr->howto = riscv_elf_rtype_to_howto (abfd, ELFNN_R_TYPE (dst->r_info));
130 return cache_ptr->howto != NULL;
131 }
132
133 static void
134 riscv_elf_append_rela (bfd *abfd, asection *s, Elf_Internal_Rela *rel)
135 {
136 const struct elf_backend_data *bed;
137 bfd_byte *loc;
138
139 bed = get_elf_backend_data (abfd);
140 loc = s->contents + (s->reloc_count++ * bed->s->sizeof_rela);
141 bed->s->swap_reloca_out (abfd, rel, loc);
142 }
143
144 /* PLT/GOT stuff. */
145
146 #define PLT_HEADER_INSNS 8
147 #define PLT_ENTRY_INSNS 4
148 #define PLT_HEADER_SIZE (PLT_HEADER_INSNS * 4)
149 #define PLT_ENTRY_SIZE (PLT_ENTRY_INSNS * 4)
150
151 #define GOT_ENTRY_SIZE RISCV_ELF_WORD_BYTES
152
153 #define GOTPLT_HEADER_SIZE (2 * GOT_ENTRY_SIZE)
154
155 #define sec_addr(sec) ((sec)->output_section->vma + (sec)->output_offset)
156
157 static bfd_vma
158 riscv_elf_got_plt_val (bfd_vma plt_index, struct bfd_link_info *info)
159 {
160 return sec_addr (riscv_elf_hash_table (info)->elf.sgotplt)
161 + GOTPLT_HEADER_SIZE + (plt_index * GOT_ENTRY_SIZE);
162 }
163
164 #if ARCH_SIZE == 32
165 # define MATCH_LREG MATCH_LW
166 #else
167 # define MATCH_LREG MATCH_LD
168 #endif
169
170 /* Generate a PLT header. */
171
172 static bfd_boolean
173 riscv_make_plt_header (bfd *output_bfd, bfd_vma gotplt_addr, bfd_vma addr,
174 uint32_t *entry)
175 {
176 bfd_vma gotplt_offset_high = RISCV_PCREL_HIGH_PART (gotplt_addr, addr);
177 bfd_vma gotplt_offset_low = RISCV_PCREL_LOW_PART (gotplt_addr, addr);
178
179 /* RVE has no t3 register, so this won't work, and is not supported. */
180 if (elf_elfheader (output_bfd)->e_flags & EF_RISCV_RVE)
181 {
182 _bfd_error_handler (_("%pB: warning: RVE PLT generation not supported"),
183 output_bfd);
184 return FALSE;
185 }
186
187 /* auipc t2, %hi(.got.plt)
188 sub t1, t1, t3 # shifted .got.plt offset + hdr size + 12
189 l[w|d] t3, %lo(.got.plt)(t2) # _dl_runtime_resolve
190 addi t1, t1, -(hdr size + 12) # shifted .got.plt offset
191 addi t0, t2, %lo(.got.plt) # &.got.plt
192 srli t1, t1, log2(16/PTRSIZE) # .got.plt offset
193 l[w|d] t0, PTRSIZE(t0) # link map
194 jr t3 */
195
196 entry[0] = RISCV_UTYPE (AUIPC, X_T2, gotplt_offset_high);
197 entry[1] = RISCV_RTYPE (SUB, X_T1, X_T1, X_T3);
198 entry[2] = RISCV_ITYPE (LREG, X_T3, X_T2, gotplt_offset_low);
199 entry[3] = RISCV_ITYPE (ADDI, X_T1, X_T1, -(PLT_HEADER_SIZE + 12));
200 entry[4] = RISCV_ITYPE (ADDI, X_T0, X_T2, gotplt_offset_low);
201 entry[5] = RISCV_ITYPE (SRLI, X_T1, X_T1, 4 - RISCV_ELF_LOG_WORD_BYTES);
202 entry[6] = RISCV_ITYPE (LREG, X_T0, X_T0, RISCV_ELF_WORD_BYTES);
203 entry[7] = RISCV_ITYPE (JALR, 0, X_T3, 0);
204
205 return TRUE;
206 }
207
208 /* Generate a PLT entry. */
209
210 static bfd_boolean
211 riscv_make_plt_entry (bfd *output_bfd, bfd_vma got, bfd_vma addr,
212 uint32_t *entry)
213 {
214 /* RVE has no t3 register, so this won't work, and is not supported. */
215 if (elf_elfheader (output_bfd)->e_flags & EF_RISCV_RVE)
216 {
217 _bfd_error_handler (_("%pB: warning: RVE PLT generation not supported"),
218 output_bfd);
219 return FALSE;
220 }
221
222 /* auipc t3, %hi(.got.plt entry)
223 l[w|d] t3, %lo(.got.plt entry)(t3)
224 jalr t1, t3
225 nop */
226
227 entry[0] = RISCV_UTYPE (AUIPC, X_T3, RISCV_PCREL_HIGH_PART (got, addr));
228 entry[1] = RISCV_ITYPE (LREG, X_T3, X_T3, RISCV_PCREL_LOW_PART (got, addr));
229 entry[2] = RISCV_ITYPE (JALR, X_T1, X_T3, 0);
230 entry[3] = RISCV_NOP;
231
232 return TRUE;
233 }
234
235 /* Create an entry in an RISC-V ELF linker hash table. */
236
237 static struct bfd_hash_entry *
238 link_hash_newfunc (struct bfd_hash_entry *entry,
239 struct bfd_hash_table *table, const char *string)
240 {
241 /* Allocate the structure if it has not already been allocated by a
242 subclass. */
243 if (entry == NULL)
244 {
245 entry =
246 bfd_hash_allocate (table,
247 sizeof (struct riscv_elf_link_hash_entry));
248 if (entry == NULL)
249 return entry;
250 }
251
252 /* Call the allocation method of the superclass. */
253 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
254 if (entry != NULL)
255 {
256 struct riscv_elf_link_hash_entry *eh;
257
258 eh = (struct riscv_elf_link_hash_entry *) entry;
259 eh->dyn_relocs = NULL;
260 eh->tls_type = GOT_UNKNOWN;
261 }
262
263 return entry;
264 }
265
266 /* Create a RISC-V ELF linker hash table. */
267
268 static struct bfd_link_hash_table *
269 riscv_elf_link_hash_table_create (bfd *abfd)
270 {
271 struct riscv_elf_link_hash_table *ret;
272 bfd_size_type amt = sizeof (struct riscv_elf_link_hash_table);
273
274 ret = (struct riscv_elf_link_hash_table *) bfd_zmalloc (amt);
275 if (ret == NULL)
276 return NULL;
277
278 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc,
279 sizeof (struct riscv_elf_link_hash_entry),
280 RISCV_ELF_DATA))
281 {
282 free (ret);
283 return NULL;
284 }
285
286 ret->max_alignment = (bfd_vma) -1;
287 return &ret->elf.root;
288 }
289
290 /* Create the .got section. */
291
292 static bfd_boolean
293 riscv_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
294 {
295 flagword flags;
296 asection *s, *s_got;
297 struct elf_link_hash_entry *h;
298 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
299 struct elf_link_hash_table *htab = elf_hash_table (info);
300
301 /* This function may be called more than once. */
302 if (htab->sgot != NULL)
303 return TRUE;
304
305 flags = bed->dynamic_sec_flags;
306
307 s = bfd_make_section_anyway_with_flags (abfd,
308 (bed->rela_plts_and_copies_p
309 ? ".rela.got" : ".rel.got"),
310 (bed->dynamic_sec_flags
311 | SEC_READONLY));
312 if (s == NULL
313 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
314 return FALSE;
315 htab->srelgot = s;
316
317 s = s_got = bfd_make_section_anyway_with_flags (abfd, ".got", flags);
318 if (s == NULL
319 || !bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
320 return FALSE;
321 htab->sgot = s;
322
323 /* The first bit of the global offset table is the header. */
324 s->size += bed->got_header_size;
325
326 if (bed->want_got_plt)
327 {
328 s = bfd_make_section_anyway_with_flags (abfd, ".got.plt", flags);
329 if (s == NULL
330 || !bfd_set_section_alignment (abfd, s,
331 bed->s->log_file_align))
332 return FALSE;
333 htab->sgotplt = s;
334
335 /* Reserve room for the header. */
336 s->size += GOTPLT_HEADER_SIZE;
337 }
338
339 if (bed->want_got_sym)
340 {
341 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
342 section. We don't do this in the linker script because we don't want
343 to define the symbol if we are not creating a global offset
344 table. */
345 h = _bfd_elf_define_linkage_sym (abfd, info, s_got,
346 "_GLOBAL_OFFSET_TABLE_");
347 elf_hash_table (info)->hgot = h;
348 if (h == NULL)
349 return FALSE;
350 }
351
352 return TRUE;
353 }
354
355 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
356 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our
357 hash table. */
358
359 static bfd_boolean
360 riscv_elf_create_dynamic_sections (bfd *dynobj,
361 struct bfd_link_info *info)
362 {
363 struct riscv_elf_link_hash_table *htab;
364
365 htab = riscv_elf_hash_table (info);
366 BFD_ASSERT (htab != NULL);
367
368 if (!riscv_elf_create_got_section (dynobj, info))
369 return FALSE;
370
371 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
372 return FALSE;
373
374 if (!bfd_link_pic (info))
375 {
376 htab->sdyntdata =
377 bfd_make_section_anyway_with_flags (dynobj, ".tdata.dyn",
378 (SEC_ALLOC | SEC_THREAD_LOCAL
379 | SEC_LINKER_CREATED));
380 }
381
382 if (!htab->elf.splt || !htab->elf.srelplt || !htab->elf.sdynbss
383 || (!bfd_link_pic (info) && (!htab->elf.srelbss || !htab->sdyntdata)))
384 abort ();
385
386 return TRUE;
387 }
388
389 /* Copy the extra info we tack onto an elf_link_hash_entry. */
390
391 static void
392 riscv_elf_copy_indirect_symbol (struct bfd_link_info *info,
393 struct elf_link_hash_entry *dir,
394 struct elf_link_hash_entry *ind)
395 {
396 struct riscv_elf_link_hash_entry *edir, *eind;
397
398 edir = (struct riscv_elf_link_hash_entry *) dir;
399 eind = (struct riscv_elf_link_hash_entry *) ind;
400
401 if (eind->dyn_relocs != NULL)
402 {
403 if (edir->dyn_relocs != NULL)
404 {
405 struct elf_dyn_relocs **pp;
406 struct elf_dyn_relocs *p;
407
408 /* Add reloc counts against the indirect sym to the direct sym
409 list. Merge any entries against the same section. */
410 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
411 {
412 struct elf_dyn_relocs *q;
413
414 for (q = edir->dyn_relocs; q != NULL; q = q->next)
415 if (q->sec == p->sec)
416 {
417 q->pc_count += p->pc_count;
418 q->count += p->count;
419 *pp = p->next;
420 break;
421 }
422 if (q == NULL)
423 pp = &p->next;
424 }
425 *pp = edir->dyn_relocs;
426 }
427
428 edir->dyn_relocs = eind->dyn_relocs;
429 eind->dyn_relocs = NULL;
430 }
431
432 if (ind->root.type == bfd_link_hash_indirect
433 && dir->got.refcount <= 0)
434 {
435 edir->tls_type = eind->tls_type;
436 eind->tls_type = GOT_UNKNOWN;
437 }
438 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
439 }
440
441 static bfd_boolean
442 riscv_elf_record_tls_type (bfd *abfd, struct elf_link_hash_entry *h,
443 unsigned long symndx, char tls_type)
444 {
445 char *new_tls_type = &_bfd_riscv_elf_tls_type (abfd, h, symndx);
446
447 *new_tls_type |= tls_type;
448 if ((*new_tls_type & GOT_NORMAL) && (*new_tls_type & ~GOT_NORMAL))
449 {
450 (*_bfd_error_handler)
451 (_("%pB: `%s' accessed both as normal and thread local symbol"),
452 abfd, h ? h->root.root.string : "<local>");
453 return FALSE;
454 }
455 return TRUE;
456 }
457
458 static bfd_boolean
459 riscv_elf_record_got_reference (bfd *abfd, struct bfd_link_info *info,
460 struct elf_link_hash_entry *h, long symndx)
461 {
462 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info);
463 Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
464
465 if (htab->elf.sgot == NULL)
466 {
467 if (!riscv_elf_create_got_section (htab->elf.dynobj, info))
468 return FALSE;
469 }
470
471 if (h != NULL)
472 {
473 h->got.refcount += 1;
474 return TRUE;
475 }
476
477 /* This is a global offset table entry for a local symbol. */
478 if (elf_local_got_refcounts (abfd) == NULL)
479 {
480 bfd_size_type size = symtab_hdr->sh_info * (sizeof (bfd_vma) + 1);
481 if (!(elf_local_got_refcounts (abfd) = bfd_zalloc (abfd, size)))
482 return FALSE;
483 _bfd_riscv_elf_local_got_tls_type (abfd)
484 = (char *) (elf_local_got_refcounts (abfd) + symtab_hdr->sh_info);
485 }
486 elf_local_got_refcounts (abfd) [symndx] += 1;
487
488 return TRUE;
489 }
490
491 static bfd_boolean
492 bad_static_reloc (bfd *abfd, unsigned r_type, struct elf_link_hash_entry *h)
493 {
494 reloc_howto_type * r = riscv_elf_rtype_to_howto (abfd, r_type);
495
496 (*_bfd_error_handler)
497 (_("%pB: relocation %s against `%s' can not be used when making a shared "
498 "object; recompile with -fPIC"),
499 abfd, r ? r->name : _("<unknown>"),
500 h != NULL ? h->root.root.string : "a local symbol");
501 bfd_set_error (bfd_error_bad_value);
502 return FALSE;
503 }
504 /* Look through the relocs for a section during the first phase, and
505 allocate space in the global offset table or procedure linkage
506 table. */
507
508 static bfd_boolean
509 riscv_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
510 asection *sec, const Elf_Internal_Rela *relocs)
511 {
512 struct riscv_elf_link_hash_table *htab;
513 Elf_Internal_Shdr *symtab_hdr;
514 struct elf_link_hash_entry **sym_hashes;
515 const Elf_Internal_Rela *rel;
516 asection *sreloc = NULL;
517
518 if (bfd_link_relocatable (info))
519 return TRUE;
520
521 htab = riscv_elf_hash_table (info);
522 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
523 sym_hashes = elf_sym_hashes (abfd);
524
525 if (htab->elf.dynobj == NULL)
526 htab->elf.dynobj = abfd;
527
528 for (rel = relocs; rel < relocs + sec->reloc_count; rel++)
529 {
530 unsigned int r_type;
531 unsigned int r_symndx;
532 struct elf_link_hash_entry *h;
533
534 r_symndx = ELFNN_R_SYM (rel->r_info);
535 r_type = ELFNN_R_TYPE (rel->r_info);
536
537 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
538 {
539 (*_bfd_error_handler) (_("%pB: bad symbol index: %d"),
540 abfd, r_symndx);
541 return FALSE;
542 }
543
544 if (r_symndx < symtab_hdr->sh_info)
545 h = NULL;
546 else
547 {
548 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
549 while (h->root.type == bfd_link_hash_indirect
550 || h->root.type == bfd_link_hash_warning)
551 h = (struct elf_link_hash_entry *) h->root.u.i.link;
552 }
553
554 switch (r_type)
555 {
556 case R_RISCV_TLS_GD_HI20:
557 if (!riscv_elf_record_got_reference (abfd, info, h, r_symndx)
558 || !riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_TLS_GD))
559 return FALSE;
560 break;
561
562 case R_RISCV_TLS_GOT_HI20:
563 if (bfd_link_pic (info))
564 info->flags |= DF_STATIC_TLS;
565 if (!riscv_elf_record_got_reference (abfd, info, h, r_symndx)
566 || !riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_TLS_IE))
567 return FALSE;
568 break;
569
570 case R_RISCV_GOT_HI20:
571 if (!riscv_elf_record_got_reference (abfd, info, h, r_symndx)
572 || !riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_NORMAL))
573 return FALSE;
574 break;
575
576 case R_RISCV_CALL_PLT:
577 /* This symbol requires a procedure linkage table entry. We
578 actually build the entry in adjust_dynamic_symbol,
579 because this might be a case of linking PIC code without
580 linking in any dynamic objects, in which case we don't
581 need to generate a procedure linkage table after all. */
582
583 if (h != NULL)
584 {
585 h->needs_plt = 1;
586 h->plt.refcount += 1;
587 }
588 break;
589
590 case R_RISCV_CALL:
591 case R_RISCV_JAL:
592 case R_RISCV_BRANCH:
593 case R_RISCV_RVC_BRANCH:
594 case R_RISCV_RVC_JUMP:
595 case R_RISCV_PCREL_HI20:
596 /* In shared libraries, these relocs are known to bind locally. */
597 if (bfd_link_pic (info))
598 break;
599 goto static_reloc;
600
601 case R_RISCV_TPREL_HI20:
602 if (!bfd_link_executable (info))
603 return bad_static_reloc (abfd, r_type, h);
604 if (h != NULL)
605 riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_TLS_LE);
606 goto static_reloc;
607
608 case R_RISCV_HI20:
609 if (bfd_link_pic (info))
610 return bad_static_reloc (abfd, r_type, h);
611 /* Fall through. */
612
613 case R_RISCV_COPY:
614 case R_RISCV_JUMP_SLOT:
615 case R_RISCV_RELATIVE:
616 case R_RISCV_64:
617 case R_RISCV_32:
618 /* Fall through. */
619
620 static_reloc:
621 /* This reloc might not bind locally. */
622 if (h != NULL)
623 h->non_got_ref = 1;
624
625 if (h != NULL && !bfd_link_pic (info))
626 {
627 /* We may need a .plt entry if the function this reloc
628 refers to is in a shared lib. */
629 h->plt.refcount += 1;
630 }
631
632 /* If we are creating a shared library, and this is a reloc
633 against a global symbol, or a non PC relative reloc
634 against a local symbol, then we need to copy the reloc
635 into the shared library. However, if we are linking with
636 -Bsymbolic, we do not need to copy a reloc against a
637 global symbol which is defined in an object we are
638 including in the link (i.e., DEF_REGULAR is set). At
639 this point we have not seen all the input files, so it is
640 possible that DEF_REGULAR is not set now but will be set
641 later (it is never cleared). In case of a weak definition,
642 DEF_REGULAR may be cleared later by a strong definition in
643 a shared library. We account for that possibility below by
644 storing information in the relocs_copied field of the hash
645 table entry. A similar situation occurs when creating
646 shared libraries and symbol visibility changes render the
647 symbol local.
648
649 If on the other hand, we are creating an executable, we
650 may need to keep relocations for symbols satisfied by a
651 dynamic library if we manage to avoid copy relocs for the
652 symbol. */
653 reloc_howto_type * r = riscv_elf_rtype_to_howto (abfd, r_type);
654
655 if ((bfd_link_pic (info)
656 && (sec->flags & SEC_ALLOC) != 0
657 && ((r != NULL && ! r->pc_relative)
658 || (h != NULL
659 && (! info->symbolic
660 || h->root.type == bfd_link_hash_defweak
661 || !h->def_regular))))
662 || (!bfd_link_pic (info)
663 && (sec->flags & SEC_ALLOC) != 0
664 && h != NULL
665 && (h->root.type == bfd_link_hash_defweak
666 || !h->def_regular)))
667 {
668 struct elf_dyn_relocs *p;
669 struct elf_dyn_relocs **head;
670
671 /* When creating a shared object, we must copy these
672 relocs into the output file. We create a reloc
673 section in dynobj and make room for the reloc. */
674 if (sreloc == NULL)
675 {
676 sreloc = _bfd_elf_make_dynamic_reloc_section
677 (sec, htab->elf.dynobj, RISCV_ELF_LOG_WORD_BYTES,
678 abfd, /*rela?*/ TRUE);
679
680 if (sreloc == NULL)
681 return FALSE;
682 }
683
684 /* If this is a global symbol, we count the number of
685 relocations we need for this symbol. */
686 if (h != NULL)
687 head = &((struct riscv_elf_link_hash_entry *) h)->dyn_relocs;
688 else
689 {
690 /* Track dynamic relocs needed for local syms too.
691 We really need local syms available to do this
692 easily. Oh well. */
693
694 asection *s;
695 void *vpp;
696 Elf_Internal_Sym *isym;
697
698 isym = bfd_sym_from_r_symndx (&htab->sym_cache,
699 abfd, r_symndx);
700 if (isym == NULL)
701 return FALSE;
702
703 s = bfd_section_from_elf_index (abfd, isym->st_shndx);
704 if (s == NULL)
705 s = sec;
706
707 vpp = &elf_section_data (s)->local_dynrel;
708 head = (struct elf_dyn_relocs **) vpp;
709 }
710
711 p = *head;
712 if (p == NULL || p->sec != sec)
713 {
714 bfd_size_type amt = sizeof *p;
715 p = ((struct elf_dyn_relocs *)
716 bfd_alloc (htab->elf.dynobj, amt));
717 if (p == NULL)
718 return FALSE;
719 p->next = *head;
720 *head = p;
721 p->sec = sec;
722 p->count = 0;
723 p->pc_count = 0;
724 }
725
726 p->count += 1;
727 p->pc_count += r == NULL ? 0 : r->pc_relative;
728 }
729
730 break;
731
732 case R_RISCV_GNU_VTINHERIT:
733 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
734 return FALSE;
735 break;
736
737 case R_RISCV_GNU_VTENTRY:
738 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
739 return FALSE;
740 break;
741
742 default:
743 break;
744 }
745 }
746
747 return TRUE;
748 }
749
750 static asection *
751 riscv_elf_gc_mark_hook (asection *sec,
752 struct bfd_link_info *info,
753 Elf_Internal_Rela *rel,
754 struct elf_link_hash_entry *h,
755 Elf_Internal_Sym *sym)
756 {
757 if (h != NULL)
758 switch (ELFNN_R_TYPE (rel->r_info))
759 {
760 case R_RISCV_GNU_VTINHERIT:
761 case R_RISCV_GNU_VTENTRY:
762 return NULL;
763 }
764
765 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
766 }
767
768 /* Find dynamic relocs for H that apply to read-only sections. */
769
770 static asection *
771 readonly_dynrelocs (struct elf_link_hash_entry *h)
772 {
773 struct elf_dyn_relocs *p;
774
775 for (p = riscv_elf_hash_entry (h)->dyn_relocs; p != NULL; p = p->next)
776 {
777 asection *s = p->sec->output_section;
778
779 if (s != NULL && (s->flags & SEC_READONLY) != 0)
780 return p->sec;
781 }
782 return NULL;
783 }
784
785 /* Adjust a symbol defined by a dynamic object and referenced by a
786 regular object. The current definition is in some section of the
787 dynamic object, but we're not including those sections. We have to
788 change the definition to something the rest of the link can
789 understand. */
790
791 static bfd_boolean
792 riscv_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
793 struct elf_link_hash_entry *h)
794 {
795 struct riscv_elf_link_hash_table *htab;
796 struct riscv_elf_link_hash_entry * eh;
797 bfd *dynobj;
798 asection *s, *srel;
799
800 htab = riscv_elf_hash_table (info);
801 BFD_ASSERT (htab != NULL);
802
803 dynobj = htab->elf.dynobj;
804
805 /* Make sure we know what is going on here. */
806 BFD_ASSERT (dynobj != NULL
807 && (h->needs_plt
808 || h->type == STT_GNU_IFUNC
809 || h->is_weakalias
810 || (h->def_dynamic
811 && h->ref_regular
812 && !h->def_regular)));
813
814 /* If this is a function, put it in the procedure linkage table. We
815 will fill in the contents of the procedure linkage table later
816 (although we could actually do it here). */
817 if (h->type == STT_FUNC || h->type == STT_GNU_IFUNC || h->needs_plt)
818 {
819 if (h->plt.refcount <= 0
820 || SYMBOL_CALLS_LOCAL (info, h)
821 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
822 && h->root.type == bfd_link_hash_undefweak))
823 {
824 /* This case can occur if we saw a R_RISCV_CALL_PLT reloc in an
825 input file, but the symbol was never referred to by a dynamic
826 object, or if all references were garbage collected. In such
827 a case, we don't actually need to build a PLT entry. */
828 h->plt.offset = (bfd_vma) -1;
829 h->needs_plt = 0;
830 }
831
832 return TRUE;
833 }
834 else
835 h->plt.offset = (bfd_vma) -1;
836
837 /* If this is a weak symbol, and there is a real definition, the
838 processor independent code will have arranged for us to see the
839 real definition first, and we can just use the same value. */
840 if (h->is_weakalias)
841 {
842 struct elf_link_hash_entry *def = weakdef (h);
843 BFD_ASSERT (def->root.type == bfd_link_hash_defined);
844 h->root.u.def.section = def->root.u.def.section;
845 h->root.u.def.value = def->root.u.def.value;
846 return TRUE;
847 }
848
849 /* This is a reference to a symbol defined by a dynamic object which
850 is not a function. */
851
852 /* If we are creating a shared library, we must presume that the
853 only references to the symbol are via the global offset table.
854 For such cases we need not do anything here; the relocations will
855 be handled correctly by relocate_section. */
856 if (bfd_link_pic (info))
857 return TRUE;
858
859 /* If there are no references to this symbol that do not use the
860 GOT, we don't need to generate a copy reloc. */
861 if (!h->non_got_ref)
862 return TRUE;
863
864 /* If -z nocopyreloc was given, we won't generate them either. */
865 if (info->nocopyreloc)
866 {
867 h->non_got_ref = 0;
868 return TRUE;
869 }
870
871 /* If we don't find any dynamic relocs in read-only sections, then
872 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
873 if (!readonly_dynrelocs (h))
874 {
875 h->non_got_ref = 0;
876 return TRUE;
877 }
878
879 /* We must allocate the symbol in our .dynbss section, which will
880 become part of the .bss section of the executable. There will be
881 an entry for this symbol in the .dynsym section. The dynamic
882 object will contain position independent code, so all references
883 from the dynamic object to this symbol will go through the global
884 offset table. The dynamic linker will use the .dynsym entry to
885 determine the address it must put in the global offset table, so
886 both the dynamic object and the regular object will refer to the
887 same memory location for the variable. */
888
889 /* We must generate a R_RISCV_COPY reloc to tell the dynamic linker
890 to copy the initial value out of the dynamic object and into the
891 runtime process image. We need to remember the offset into the
892 .rel.bss section we are going to use. */
893 eh = (struct riscv_elf_link_hash_entry *) h;
894 if (eh->tls_type & ~GOT_NORMAL)
895 {
896 s = htab->sdyntdata;
897 srel = htab->elf.srelbss;
898 }
899 else if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
900 {
901 s = htab->elf.sdynrelro;
902 srel = htab->elf.sreldynrelro;
903 }
904 else
905 {
906 s = htab->elf.sdynbss;
907 srel = htab->elf.srelbss;
908 }
909 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
910 {
911 srel->size += sizeof (ElfNN_External_Rela);
912 h->needs_copy = 1;
913 }
914
915 return _bfd_elf_adjust_dynamic_copy (info, h, s);
916 }
917
918 /* Allocate space in .plt, .got and associated reloc sections for
919 dynamic relocs. */
920
921 static bfd_boolean
922 allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
923 {
924 struct bfd_link_info *info;
925 struct riscv_elf_link_hash_table *htab;
926 struct riscv_elf_link_hash_entry *eh;
927 struct elf_dyn_relocs *p;
928
929 if (h->root.type == bfd_link_hash_indirect)
930 return TRUE;
931
932 info = (struct bfd_link_info *) inf;
933 htab = riscv_elf_hash_table (info);
934 BFD_ASSERT (htab != NULL);
935
936 if (htab->elf.dynamic_sections_created
937 && h->plt.refcount > 0)
938 {
939 /* Make sure this symbol is output as a dynamic symbol.
940 Undefined weak syms won't yet be marked as dynamic. */
941 if (h->dynindx == -1
942 && !h->forced_local)
943 {
944 if (! bfd_elf_link_record_dynamic_symbol (info, h))
945 return FALSE;
946 }
947
948 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, bfd_link_pic (info), h))
949 {
950 asection *s = htab->elf.splt;
951
952 if (s->size == 0)
953 s->size = PLT_HEADER_SIZE;
954
955 h->plt.offset = s->size;
956
957 /* Make room for this entry. */
958 s->size += PLT_ENTRY_SIZE;
959
960 /* We also need to make an entry in the .got.plt section. */
961 htab->elf.sgotplt->size += GOT_ENTRY_SIZE;
962
963 /* We also need to make an entry in the .rela.plt section. */
964 htab->elf.srelplt->size += sizeof (ElfNN_External_Rela);
965
966 /* If this symbol is not defined in a regular file, and we are
967 not generating a shared library, then set the symbol to this
968 location in the .plt. This is required to make function
969 pointers compare as equal between the normal executable and
970 the shared library. */
971 if (! bfd_link_pic (info)
972 && !h->def_regular)
973 {
974 h->root.u.def.section = s;
975 h->root.u.def.value = h->plt.offset;
976 }
977 }
978 else
979 {
980 h->plt.offset = (bfd_vma) -1;
981 h->needs_plt = 0;
982 }
983 }
984 else
985 {
986 h->plt.offset = (bfd_vma) -1;
987 h->needs_plt = 0;
988 }
989
990 if (h->got.refcount > 0)
991 {
992 asection *s;
993 bfd_boolean dyn;
994 int tls_type = riscv_elf_hash_entry (h)->tls_type;
995
996 /* Make sure this symbol is output as a dynamic symbol.
997 Undefined weak syms won't yet be marked as dynamic. */
998 if (h->dynindx == -1
999 && !h->forced_local)
1000 {
1001 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1002 return FALSE;
1003 }
1004
1005 s = htab->elf.sgot;
1006 h->got.offset = s->size;
1007 dyn = htab->elf.dynamic_sections_created;
1008 if (tls_type & (GOT_TLS_GD | GOT_TLS_IE))
1009 {
1010 /* TLS_GD needs two dynamic relocs and two GOT slots. */
1011 if (tls_type & GOT_TLS_GD)
1012 {
1013 s->size += 2 * RISCV_ELF_WORD_BYTES;
1014 htab->elf.srelgot->size += 2 * sizeof (ElfNN_External_Rela);
1015 }
1016
1017 /* TLS_IE needs one dynamic reloc and one GOT slot. */
1018 if (tls_type & GOT_TLS_IE)
1019 {
1020 s->size += RISCV_ELF_WORD_BYTES;
1021 htab->elf.srelgot->size += sizeof (ElfNN_External_Rela);
1022 }
1023 }
1024 else
1025 {
1026 s->size += RISCV_ELF_WORD_BYTES;
1027 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, bfd_link_pic (info), h)
1028 && ! UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
1029 htab->elf.srelgot->size += sizeof (ElfNN_External_Rela);
1030 }
1031 }
1032 else
1033 h->got.offset = (bfd_vma) -1;
1034
1035 eh = (struct riscv_elf_link_hash_entry *) h;
1036 if (eh->dyn_relocs == NULL)
1037 return TRUE;
1038
1039 /* In the shared -Bsymbolic case, discard space allocated for
1040 dynamic pc-relative relocs against symbols which turn out to be
1041 defined in regular objects. For the normal shared case, discard
1042 space for pc-relative relocs that have become local due to symbol
1043 visibility changes. */
1044
1045 if (bfd_link_pic (info))
1046 {
1047 if (SYMBOL_CALLS_LOCAL (info, h))
1048 {
1049 struct elf_dyn_relocs **pp;
1050
1051 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1052 {
1053 p->count -= p->pc_count;
1054 p->pc_count = 0;
1055 if (p->count == 0)
1056 *pp = p->next;
1057 else
1058 pp = &p->next;
1059 }
1060 }
1061
1062 /* Also discard relocs on undefined weak syms with non-default
1063 visibility. */
1064 if (eh->dyn_relocs != NULL
1065 && h->root.type == bfd_link_hash_undefweak)
1066 {
1067 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1068 || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
1069 eh->dyn_relocs = NULL;
1070
1071 /* Make sure undefined weak symbols are output as a dynamic
1072 symbol in PIEs. */
1073 else if (h->dynindx == -1
1074 && !h->forced_local)
1075 {
1076 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1077 return FALSE;
1078 }
1079 }
1080 }
1081 else
1082 {
1083 /* For the non-shared case, discard space for relocs against
1084 symbols which turn out to need copy relocs or are not
1085 dynamic. */
1086
1087 if (!h->non_got_ref
1088 && ((h->def_dynamic
1089 && !h->def_regular)
1090 || (htab->elf.dynamic_sections_created
1091 && (h->root.type == bfd_link_hash_undefweak
1092 || h->root.type == bfd_link_hash_undefined))))
1093 {
1094 /* Make sure this symbol is output as a dynamic symbol.
1095 Undefined weak syms won't yet be marked as dynamic. */
1096 if (h->dynindx == -1
1097 && !h->forced_local)
1098 {
1099 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1100 return FALSE;
1101 }
1102
1103 /* If that succeeded, we know we'll be keeping all the
1104 relocs. */
1105 if (h->dynindx != -1)
1106 goto keep;
1107 }
1108
1109 eh->dyn_relocs = NULL;
1110
1111 keep: ;
1112 }
1113
1114 /* Finally, allocate space. */
1115 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1116 {
1117 asection *sreloc = elf_section_data (p->sec)->sreloc;
1118 sreloc->size += p->count * sizeof (ElfNN_External_Rela);
1119 }
1120
1121 return TRUE;
1122 }
1123
1124 /* Set DF_TEXTREL if we find any dynamic relocs that apply to
1125 read-only sections. */
1126
1127 static bfd_boolean
1128 maybe_set_textrel (struct elf_link_hash_entry *h, void *info_p)
1129 {
1130 asection *sec;
1131
1132 if (h->root.type == bfd_link_hash_indirect)
1133 return TRUE;
1134
1135 sec = readonly_dynrelocs (h);
1136 if (sec != NULL)
1137 {
1138 struct bfd_link_info *info = (struct bfd_link_info *) info_p;
1139
1140 info->flags |= DF_TEXTREL;
1141 info->callbacks->minfo
1142 (_("%pB: dynamic relocation against `%pT' in read-only section `%pA'\n"),
1143 sec->owner, h->root.root.string, sec);
1144
1145 /* Not an error, just cut short the traversal. */
1146 return FALSE;
1147 }
1148 return TRUE;
1149 }
1150
1151 static bfd_boolean
1152 riscv_elf_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
1153 {
1154 struct riscv_elf_link_hash_table *htab;
1155 bfd *dynobj;
1156 asection *s;
1157 bfd *ibfd;
1158
1159 htab = riscv_elf_hash_table (info);
1160 BFD_ASSERT (htab != NULL);
1161 dynobj = htab->elf.dynobj;
1162 BFD_ASSERT (dynobj != NULL);
1163
1164 if (elf_hash_table (info)->dynamic_sections_created)
1165 {
1166 /* Set the contents of the .interp section to the interpreter. */
1167 if (bfd_link_executable (info) && !info->nointerp)
1168 {
1169 s = bfd_get_linker_section (dynobj, ".interp");
1170 BFD_ASSERT (s != NULL);
1171 s->size = strlen (ELFNN_DYNAMIC_INTERPRETER) + 1;
1172 s->contents = (unsigned char *) ELFNN_DYNAMIC_INTERPRETER;
1173 }
1174 }
1175
1176 /* Set up .got offsets for local syms, and space for local dynamic
1177 relocs. */
1178 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
1179 {
1180 bfd_signed_vma *local_got;
1181 bfd_signed_vma *end_local_got;
1182 char *local_tls_type;
1183 bfd_size_type locsymcount;
1184 Elf_Internal_Shdr *symtab_hdr;
1185 asection *srel;
1186
1187 if (! is_riscv_elf (ibfd))
1188 continue;
1189
1190 for (s = ibfd->sections; s != NULL; s = s->next)
1191 {
1192 struct elf_dyn_relocs *p;
1193
1194 for (p = elf_section_data (s)->local_dynrel; p != NULL; p = p->next)
1195 {
1196 if (!bfd_is_abs_section (p->sec)
1197 && bfd_is_abs_section (p->sec->output_section))
1198 {
1199 /* Input section has been discarded, either because
1200 it is a copy of a linkonce section or due to
1201 linker script /DISCARD/, so we'll be discarding
1202 the relocs too. */
1203 }
1204 else if (p->count != 0)
1205 {
1206 srel = elf_section_data (p->sec)->sreloc;
1207 srel->size += p->count * sizeof (ElfNN_External_Rela);
1208 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1209 info->flags |= DF_TEXTREL;
1210 }
1211 }
1212 }
1213
1214 local_got = elf_local_got_refcounts (ibfd);
1215 if (!local_got)
1216 continue;
1217
1218 symtab_hdr = &elf_symtab_hdr (ibfd);
1219 locsymcount = symtab_hdr->sh_info;
1220 end_local_got = local_got + locsymcount;
1221 local_tls_type = _bfd_riscv_elf_local_got_tls_type (ibfd);
1222 s = htab->elf.sgot;
1223 srel = htab->elf.srelgot;
1224 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1225 {
1226 if (*local_got > 0)
1227 {
1228 *local_got = s->size;
1229 s->size += RISCV_ELF_WORD_BYTES;
1230 if (*local_tls_type & GOT_TLS_GD)
1231 s->size += RISCV_ELF_WORD_BYTES;
1232 if (bfd_link_pic (info)
1233 || (*local_tls_type & (GOT_TLS_GD | GOT_TLS_IE)))
1234 srel->size += sizeof (ElfNN_External_Rela);
1235 }
1236 else
1237 *local_got = (bfd_vma) -1;
1238 }
1239 }
1240
1241 /* Allocate global sym .plt and .got entries, and space for global
1242 sym dynamic relocs. */
1243 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, info);
1244
1245 if (htab->elf.sgotplt)
1246 {
1247 struct elf_link_hash_entry *got;
1248 got = elf_link_hash_lookup (elf_hash_table (info),
1249 "_GLOBAL_OFFSET_TABLE_",
1250 FALSE, FALSE, FALSE);
1251
1252 /* Don't allocate .got.plt section if there are no GOT nor PLT
1253 entries and there is no refeence to _GLOBAL_OFFSET_TABLE_. */
1254 if ((got == NULL
1255 || !got->ref_regular_nonweak)
1256 && (htab->elf.sgotplt->size == GOTPLT_HEADER_SIZE)
1257 && (htab->elf.splt == NULL
1258 || htab->elf.splt->size == 0)
1259 && (htab->elf.sgot == NULL
1260 || (htab->elf.sgot->size
1261 == get_elf_backend_data (output_bfd)->got_header_size)))
1262 htab->elf.sgotplt->size = 0;
1263 }
1264
1265 /* The check_relocs and adjust_dynamic_symbol entry points have
1266 determined the sizes of the various dynamic sections. Allocate
1267 memory for them. */
1268 for (s = dynobj->sections; s != NULL; s = s->next)
1269 {
1270 if ((s->flags & SEC_LINKER_CREATED) == 0)
1271 continue;
1272
1273 if (s == htab->elf.splt
1274 || s == htab->elf.sgot
1275 || s == htab->elf.sgotplt
1276 || s == htab->elf.sdynbss
1277 || s == htab->elf.sdynrelro)
1278 {
1279 /* Strip this section if we don't need it; see the
1280 comment below. */
1281 }
1282 else if (strncmp (s->name, ".rela", 5) == 0)
1283 {
1284 if (s->size != 0)
1285 {
1286 /* We use the reloc_count field as a counter if we need
1287 to copy relocs into the output file. */
1288 s->reloc_count = 0;
1289 }
1290 }
1291 else
1292 {
1293 /* It's not one of our sections. */
1294 continue;
1295 }
1296
1297 if (s->size == 0)
1298 {
1299 /* If we don't need this section, strip it from the
1300 output file. This is mostly to handle .rela.bss and
1301 .rela.plt. We must create both sections in
1302 create_dynamic_sections, because they must be created
1303 before the linker maps input sections to output
1304 sections. The linker does that before
1305 adjust_dynamic_symbol is called, and it is that
1306 function which decides whether anything needs to go
1307 into these sections. */
1308 s->flags |= SEC_EXCLUDE;
1309 continue;
1310 }
1311
1312 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1313 continue;
1314
1315 /* Allocate memory for the section contents. Zero the memory
1316 for the benefit of .rela.plt, which has 4 unused entries
1317 at the beginning, and we don't want garbage. */
1318 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size);
1319 if (s->contents == NULL)
1320 return FALSE;
1321 }
1322
1323 if (elf_hash_table (info)->dynamic_sections_created)
1324 {
1325 /* Add some entries to the .dynamic section. We fill in the
1326 values later, in riscv_elf_finish_dynamic_sections, but we
1327 must add the entries now so that we get the correct size for
1328 the .dynamic section. The DT_DEBUG entry is filled in by the
1329 dynamic linker and used by the debugger. */
1330 #define add_dynamic_entry(TAG, VAL) \
1331 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1332
1333 if (bfd_link_executable (info))
1334 {
1335 if (!add_dynamic_entry (DT_DEBUG, 0))
1336 return FALSE;
1337 }
1338
1339 if (htab->elf.srelplt->size != 0)
1340 {
1341 if (!add_dynamic_entry (DT_PLTGOT, 0)
1342 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1343 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1344 || !add_dynamic_entry (DT_JMPREL, 0))
1345 return FALSE;
1346 }
1347
1348 if (!add_dynamic_entry (DT_RELA, 0)
1349 || !add_dynamic_entry (DT_RELASZ, 0)
1350 || !add_dynamic_entry (DT_RELAENT, sizeof (ElfNN_External_Rela)))
1351 return FALSE;
1352
1353 /* If any dynamic relocs apply to a read-only section,
1354 then we need a DT_TEXTREL entry. */
1355 if ((info->flags & DF_TEXTREL) == 0)
1356 elf_link_hash_traverse (&htab->elf, maybe_set_textrel, info);
1357
1358 if (info->flags & DF_TEXTREL)
1359 {
1360 if (!add_dynamic_entry (DT_TEXTREL, 0))
1361 return FALSE;
1362 }
1363 }
1364 #undef add_dynamic_entry
1365
1366 return TRUE;
1367 }
1368
1369 #define TP_OFFSET 0
1370 #define DTP_OFFSET 0x800
1371
1372 /* Return the relocation value for a TLS dtp-relative reloc. */
1373
1374 static bfd_vma
1375 dtpoff (struct bfd_link_info *info, bfd_vma address)
1376 {
1377 /* If tls_sec is NULL, we should have signalled an error already. */
1378 if (elf_hash_table (info)->tls_sec == NULL)
1379 return 0;
1380 return address - elf_hash_table (info)->tls_sec->vma - DTP_OFFSET;
1381 }
1382
1383 /* Return the relocation value for a static TLS tp-relative relocation. */
1384
1385 static bfd_vma
1386 tpoff (struct bfd_link_info *info, bfd_vma address)
1387 {
1388 /* If tls_sec is NULL, we should have signalled an error already. */
1389 if (elf_hash_table (info)->tls_sec == NULL)
1390 return 0;
1391 return address - elf_hash_table (info)->tls_sec->vma - TP_OFFSET;
1392 }
1393
1394 /* Return the global pointer's value, or 0 if it is not in use. */
1395
1396 static bfd_vma
1397 riscv_global_pointer_value (struct bfd_link_info *info)
1398 {
1399 struct bfd_link_hash_entry *h;
1400
1401 h = bfd_link_hash_lookup (info->hash, RISCV_GP_SYMBOL, FALSE, FALSE, TRUE);
1402 if (h == NULL || h->type != bfd_link_hash_defined)
1403 return 0;
1404
1405 return h->u.def.value + sec_addr (h->u.def.section);
1406 }
1407
1408 /* Emplace a static relocation. */
1409
1410 static bfd_reloc_status_type
1411 perform_relocation (const reloc_howto_type *howto,
1412 const Elf_Internal_Rela *rel,
1413 bfd_vma value,
1414 asection *input_section,
1415 bfd *input_bfd,
1416 bfd_byte *contents)
1417 {
1418 if (howto->pc_relative)
1419 value -= sec_addr (input_section) + rel->r_offset;
1420 value += rel->r_addend;
1421
1422 switch (ELFNN_R_TYPE (rel->r_info))
1423 {
1424 case R_RISCV_HI20:
1425 case R_RISCV_TPREL_HI20:
1426 case R_RISCV_PCREL_HI20:
1427 case R_RISCV_GOT_HI20:
1428 case R_RISCV_TLS_GOT_HI20:
1429 case R_RISCV_TLS_GD_HI20:
1430 if (ARCH_SIZE > 32 && !VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (value)))
1431 return bfd_reloc_overflow;
1432 value = ENCODE_UTYPE_IMM (RISCV_CONST_HIGH_PART (value));
1433 break;
1434
1435 case R_RISCV_LO12_I:
1436 case R_RISCV_GPREL_I:
1437 case R_RISCV_TPREL_LO12_I:
1438 case R_RISCV_TPREL_I:
1439 case R_RISCV_PCREL_LO12_I:
1440 value = ENCODE_ITYPE_IMM (value);
1441 break;
1442
1443 case R_RISCV_LO12_S:
1444 case R_RISCV_GPREL_S:
1445 case R_RISCV_TPREL_LO12_S:
1446 case R_RISCV_TPREL_S:
1447 case R_RISCV_PCREL_LO12_S:
1448 value = ENCODE_STYPE_IMM (value);
1449 break;
1450
1451 case R_RISCV_CALL:
1452 case R_RISCV_CALL_PLT:
1453 if (ARCH_SIZE > 32 && !VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (value)))
1454 return bfd_reloc_overflow;
1455 value = ENCODE_UTYPE_IMM (RISCV_CONST_HIGH_PART (value))
1456 | (ENCODE_ITYPE_IMM (value) << 32);
1457 break;
1458
1459 case R_RISCV_JAL:
1460 if (!VALID_UJTYPE_IMM (value))
1461 return bfd_reloc_overflow;
1462 value = ENCODE_UJTYPE_IMM (value);
1463 break;
1464
1465 case R_RISCV_BRANCH:
1466 if (!VALID_SBTYPE_IMM (value))
1467 return bfd_reloc_overflow;
1468 value = ENCODE_SBTYPE_IMM (value);
1469 break;
1470
1471 case R_RISCV_RVC_BRANCH:
1472 if (!VALID_RVC_B_IMM (value))
1473 return bfd_reloc_overflow;
1474 value = ENCODE_RVC_B_IMM (value);
1475 break;
1476
1477 case R_RISCV_RVC_JUMP:
1478 if (!VALID_RVC_J_IMM (value))
1479 return bfd_reloc_overflow;
1480 value = ENCODE_RVC_J_IMM (value);
1481 break;
1482
1483 case R_RISCV_RVC_LUI:
1484 if (!VALID_RVC_LUI_IMM (RISCV_CONST_HIGH_PART (value)))
1485 return bfd_reloc_overflow;
1486 value = ENCODE_RVC_LUI_IMM (RISCV_CONST_HIGH_PART (value));
1487 break;
1488
1489 case R_RISCV_32:
1490 case R_RISCV_64:
1491 case R_RISCV_ADD8:
1492 case R_RISCV_ADD16:
1493 case R_RISCV_ADD32:
1494 case R_RISCV_ADD64:
1495 case R_RISCV_SUB6:
1496 case R_RISCV_SUB8:
1497 case R_RISCV_SUB16:
1498 case R_RISCV_SUB32:
1499 case R_RISCV_SUB64:
1500 case R_RISCV_SET6:
1501 case R_RISCV_SET8:
1502 case R_RISCV_SET16:
1503 case R_RISCV_SET32:
1504 case R_RISCV_32_PCREL:
1505 case R_RISCV_TLS_DTPREL32:
1506 case R_RISCV_TLS_DTPREL64:
1507 break;
1508
1509 case R_RISCV_DELETE:
1510 return bfd_reloc_ok;
1511
1512 default:
1513 return bfd_reloc_notsupported;
1514 }
1515
1516 bfd_vma word = bfd_get (howto->bitsize, input_bfd, contents + rel->r_offset);
1517 word = (word & ~howto->dst_mask) | (value & howto->dst_mask);
1518 bfd_put (howto->bitsize, input_bfd, word, contents + rel->r_offset);
1519
1520 return bfd_reloc_ok;
1521 }
1522
1523 /* Remember all PC-relative high-part relocs we've encountered to help us
1524 later resolve the corresponding low-part relocs. */
1525
1526 typedef struct
1527 {
1528 bfd_vma address;
1529 bfd_vma value;
1530 } riscv_pcrel_hi_reloc;
1531
1532 typedef struct riscv_pcrel_lo_reloc
1533 {
1534 asection * input_section;
1535 struct bfd_link_info * info;
1536 reloc_howto_type * howto;
1537 const Elf_Internal_Rela * reloc;
1538 bfd_vma addr;
1539 const char * name;
1540 bfd_byte * contents;
1541 struct riscv_pcrel_lo_reloc * next;
1542 } riscv_pcrel_lo_reloc;
1543
1544 typedef struct
1545 {
1546 htab_t hi_relocs;
1547 riscv_pcrel_lo_reloc *lo_relocs;
1548 } riscv_pcrel_relocs;
1549
1550 static hashval_t
1551 riscv_pcrel_reloc_hash (const void *entry)
1552 {
1553 const riscv_pcrel_hi_reloc *e = entry;
1554 return (hashval_t)(e->address >> 2);
1555 }
1556
1557 static bfd_boolean
1558 riscv_pcrel_reloc_eq (const void *entry1, const void *entry2)
1559 {
1560 const riscv_pcrel_hi_reloc *e1 = entry1, *e2 = entry2;
1561 return e1->address == e2->address;
1562 }
1563
1564 static bfd_boolean
1565 riscv_init_pcrel_relocs (riscv_pcrel_relocs *p)
1566 {
1567
1568 p->lo_relocs = NULL;
1569 p->hi_relocs = htab_create (1024, riscv_pcrel_reloc_hash,
1570 riscv_pcrel_reloc_eq, free);
1571 return p->hi_relocs != NULL;
1572 }
1573
1574 static void
1575 riscv_free_pcrel_relocs (riscv_pcrel_relocs *p)
1576 {
1577 riscv_pcrel_lo_reloc *cur = p->lo_relocs;
1578
1579 while (cur != NULL)
1580 {
1581 riscv_pcrel_lo_reloc *next = cur->next;
1582 free (cur);
1583 cur = next;
1584 }
1585
1586 htab_delete (p->hi_relocs);
1587 }
1588
1589 static bfd_boolean
1590 riscv_zero_pcrel_hi_reloc (Elf_Internal_Rela *rel,
1591 struct bfd_link_info *info,
1592 bfd_vma pc,
1593 bfd_vma addr,
1594 bfd_byte *contents,
1595 const reloc_howto_type *howto,
1596 bfd *input_bfd)
1597 {
1598 /* We may need to reference low addreses in PC-relative modes even when the
1599 * PC is far away from these addresses. For example, undefweak references
1600 * need to produce the address 0 when linked. As 0 is far from the arbitrary
1601 * addresses that we can link PC-relative programs at, the linker can't
1602 * actually relocate references to those symbols. In order to allow these
1603 * programs to work we simply convert the PC-relative auipc sequences to
1604 * 0-relative lui sequences. */
1605 if (bfd_link_pic (info))
1606 return FALSE;
1607
1608 /* If it's possible to reference the symbol using auipc we do so, as that's
1609 * more in the spirit of the PC-relative relocations we're processing. */
1610 bfd_vma offset = addr - pc;
1611 if (ARCH_SIZE == 32 || VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (offset)))
1612 return FALSE;
1613
1614 /* If it's impossible to reference this with a LUI-based offset then don't
1615 * bother to convert it at all so users still see the PC-relative relocation
1616 * in the truncation message. */
1617 if (ARCH_SIZE > 32 && !VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (addr)))
1618 return FALSE;
1619
1620 rel->r_info = ELFNN_R_INFO(addr, R_RISCV_HI20);
1621
1622 bfd_vma insn = bfd_get(howto->bitsize, input_bfd, contents + rel->r_offset);
1623 insn = (insn & ~MASK_AUIPC) | MATCH_LUI;
1624 bfd_put(howto->bitsize, input_bfd, insn, contents + rel->r_offset);
1625 return TRUE;
1626 }
1627
1628 static bfd_boolean
1629 riscv_record_pcrel_hi_reloc (riscv_pcrel_relocs *p, bfd_vma addr,
1630 bfd_vma value, bfd_boolean absolute)
1631 {
1632 bfd_vma offset = absolute ? value : value - addr;
1633 riscv_pcrel_hi_reloc entry = {addr, offset};
1634 riscv_pcrel_hi_reloc **slot =
1635 (riscv_pcrel_hi_reloc **) htab_find_slot (p->hi_relocs, &entry, INSERT);
1636
1637 BFD_ASSERT (*slot == NULL);
1638 *slot = (riscv_pcrel_hi_reloc *) bfd_malloc (sizeof (riscv_pcrel_hi_reloc));
1639 if (*slot == NULL)
1640 return FALSE;
1641 **slot = entry;
1642 return TRUE;
1643 }
1644
1645 static bfd_boolean
1646 riscv_record_pcrel_lo_reloc (riscv_pcrel_relocs *p,
1647 asection *input_section,
1648 struct bfd_link_info *info,
1649 reloc_howto_type *howto,
1650 const Elf_Internal_Rela *reloc,
1651 bfd_vma addr,
1652 const char *name,
1653 bfd_byte *contents)
1654 {
1655 riscv_pcrel_lo_reloc *entry;
1656 entry = (riscv_pcrel_lo_reloc *) bfd_malloc (sizeof (riscv_pcrel_lo_reloc));
1657 if (entry == NULL)
1658 return FALSE;
1659 *entry = (riscv_pcrel_lo_reloc) {input_section, info, howto, reloc, addr,
1660 name, contents, p->lo_relocs};
1661 p->lo_relocs = entry;
1662 return TRUE;
1663 }
1664
1665 static bfd_boolean
1666 riscv_resolve_pcrel_lo_relocs (riscv_pcrel_relocs *p)
1667 {
1668 riscv_pcrel_lo_reloc *r;
1669
1670 for (r = p->lo_relocs; r != NULL; r = r->next)
1671 {
1672 bfd *input_bfd = r->input_section->owner;
1673
1674 riscv_pcrel_hi_reloc search = {r->addr, 0};
1675 riscv_pcrel_hi_reloc *entry = htab_find (p->hi_relocs, &search);
1676 if (entry == NULL
1677 /* Check for overflow into bit 11 when adding reloc addend. */
1678 || (! (entry->value & 0x800)
1679 && ((entry->value + r->reloc->r_addend) & 0x800)))
1680 {
1681 char *string = (entry == NULL
1682 ? "%pcrel_lo missing matching %pcrel_hi"
1683 : "%pcrel_lo overflow with an addend");
1684 (*r->info->callbacks->reloc_dangerous)
1685 (r->info, string, input_bfd, r->input_section, r->reloc->r_offset);
1686 return TRUE;
1687 }
1688
1689 perform_relocation (r->howto, r->reloc, entry->value, r->input_section,
1690 input_bfd, r->contents);
1691 }
1692
1693 return TRUE;
1694 }
1695
1696 /* Relocate a RISC-V ELF section.
1697
1698 The RELOCATE_SECTION function is called by the new ELF backend linker
1699 to handle the relocations for a section.
1700
1701 The relocs are always passed as Rela structures.
1702
1703 This function is responsible for adjusting the section contents as
1704 necessary, and (if generating a relocatable output file) adjusting
1705 the reloc addend as necessary.
1706
1707 This function does not have to worry about setting the reloc
1708 address or the reloc symbol index.
1709
1710 LOCAL_SYMS is a pointer to the swapped in local symbols.
1711
1712 LOCAL_SECTIONS is an array giving the section in the input file
1713 corresponding to the st_shndx field of each local symbol.
1714
1715 The global hash table entry for the global symbols can be found
1716 via elf_sym_hashes (input_bfd).
1717
1718 When generating relocatable output, this function must handle
1719 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
1720 going to be the section symbol corresponding to the output
1721 section, which means that the addend must be adjusted
1722 accordingly. */
1723
1724 static bfd_boolean
1725 riscv_elf_relocate_section (bfd *output_bfd,
1726 struct bfd_link_info *info,
1727 bfd *input_bfd,
1728 asection *input_section,
1729 bfd_byte *contents,
1730 Elf_Internal_Rela *relocs,
1731 Elf_Internal_Sym *local_syms,
1732 asection **local_sections)
1733 {
1734 Elf_Internal_Rela *rel;
1735 Elf_Internal_Rela *relend;
1736 riscv_pcrel_relocs pcrel_relocs;
1737 bfd_boolean ret = FALSE;
1738 asection *sreloc = elf_section_data (input_section)->sreloc;
1739 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info);
1740 Elf_Internal_Shdr *symtab_hdr = &elf_symtab_hdr (input_bfd);
1741 struct elf_link_hash_entry **sym_hashes = elf_sym_hashes (input_bfd);
1742 bfd_vma *local_got_offsets = elf_local_got_offsets (input_bfd);
1743 bfd_boolean absolute;
1744
1745 if (!riscv_init_pcrel_relocs (&pcrel_relocs))
1746 return FALSE;
1747
1748 relend = relocs + input_section->reloc_count;
1749 for (rel = relocs; rel < relend; rel++)
1750 {
1751 unsigned long r_symndx;
1752 struct elf_link_hash_entry *h;
1753 Elf_Internal_Sym *sym;
1754 asection *sec;
1755 bfd_vma relocation;
1756 bfd_reloc_status_type r = bfd_reloc_ok;
1757 const char *name;
1758 bfd_vma off, ie_off;
1759 bfd_boolean unresolved_reloc, is_ie = FALSE;
1760 bfd_vma pc = sec_addr (input_section) + rel->r_offset;
1761 int r_type = ELFNN_R_TYPE (rel->r_info), tls_type;
1762 reloc_howto_type *howto = riscv_elf_rtype_to_howto (input_bfd, r_type);
1763 const char *msg = NULL;
1764 bfd_boolean resolved_to_zero;
1765
1766 if (howto == NULL
1767 || r_type == R_RISCV_GNU_VTINHERIT || r_type == R_RISCV_GNU_VTENTRY)
1768 continue;
1769
1770 /* This is a final link. */
1771 r_symndx = ELFNN_R_SYM (rel->r_info);
1772 h = NULL;
1773 sym = NULL;
1774 sec = NULL;
1775 unresolved_reloc = FALSE;
1776 if (r_symndx < symtab_hdr->sh_info)
1777 {
1778 sym = local_syms + r_symndx;
1779 sec = local_sections[r_symndx];
1780 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1781 }
1782 else
1783 {
1784 bfd_boolean warned, ignored;
1785
1786 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1787 r_symndx, symtab_hdr, sym_hashes,
1788 h, sec, relocation,
1789 unresolved_reloc, warned, ignored);
1790 if (warned)
1791 {
1792 /* To avoid generating warning messages about truncated
1793 relocations, set the relocation's address to be the same as
1794 the start of this section. */
1795 if (input_section->output_section != NULL)
1796 relocation = input_section->output_section->vma;
1797 else
1798 relocation = 0;
1799 }
1800 }
1801
1802 if (sec != NULL && discarded_section (sec))
1803 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
1804 rel, 1, relend, howto, 0, contents);
1805
1806 if (bfd_link_relocatable (info))
1807 continue;
1808
1809 if (h != NULL)
1810 name = h->root.root.string;
1811 else
1812 {
1813 name = (bfd_elf_string_from_elf_section
1814 (input_bfd, symtab_hdr->sh_link, sym->st_name));
1815 if (name == NULL || *name == '\0')
1816 name = bfd_section_name (input_bfd, sec);
1817 }
1818
1819 resolved_to_zero = (h != NULL
1820 && UNDEFWEAK_NO_DYNAMIC_RELOC (info, h));
1821
1822 switch (r_type)
1823 {
1824 case R_RISCV_NONE:
1825 case R_RISCV_RELAX:
1826 case R_RISCV_TPREL_ADD:
1827 case R_RISCV_COPY:
1828 case R_RISCV_JUMP_SLOT:
1829 case R_RISCV_RELATIVE:
1830 /* These require nothing of us at all. */
1831 continue;
1832
1833 case R_RISCV_HI20:
1834 case R_RISCV_BRANCH:
1835 case R_RISCV_RVC_BRANCH:
1836 case R_RISCV_RVC_LUI:
1837 case R_RISCV_LO12_I:
1838 case R_RISCV_LO12_S:
1839 case R_RISCV_SET6:
1840 case R_RISCV_SET8:
1841 case R_RISCV_SET16:
1842 case R_RISCV_SET32:
1843 case R_RISCV_32_PCREL:
1844 case R_RISCV_DELETE:
1845 /* These require no special handling beyond perform_relocation. */
1846 break;
1847
1848 case R_RISCV_GOT_HI20:
1849 if (h != NULL)
1850 {
1851 bfd_boolean dyn, pic;
1852
1853 off = h->got.offset;
1854 BFD_ASSERT (off != (bfd_vma) -1);
1855 dyn = elf_hash_table (info)->dynamic_sections_created;
1856 pic = bfd_link_pic (info);
1857
1858 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, pic, h)
1859 || (pic && SYMBOL_REFERENCES_LOCAL (info, h)))
1860 {
1861 /* This is actually a static link, or it is a
1862 -Bsymbolic link and the symbol is defined
1863 locally, or the symbol was forced to be local
1864 because of a version file. We must initialize
1865 this entry in the global offset table. Since the
1866 offset must always be a multiple of the word size,
1867 we use the least significant bit to record whether
1868 we have initialized it already.
1869
1870 When doing a dynamic link, we create a .rela.got
1871 relocation entry to initialize the value. This
1872 is done in the finish_dynamic_symbol routine. */
1873 if ((off & 1) != 0)
1874 off &= ~1;
1875 else
1876 {
1877 bfd_put_NN (output_bfd, relocation,
1878 htab->elf.sgot->contents + off);
1879 h->got.offset |= 1;
1880 }
1881 }
1882 else
1883 unresolved_reloc = FALSE;
1884 }
1885 else
1886 {
1887 BFD_ASSERT (local_got_offsets != NULL
1888 && local_got_offsets[r_symndx] != (bfd_vma) -1);
1889
1890 off = local_got_offsets[r_symndx];
1891
1892 /* The offset must always be a multiple of the word size.
1893 So, we can use the least significant bit to record
1894 whether we have already processed this entry. */
1895 if ((off & 1) != 0)
1896 off &= ~1;
1897 else
1898 {
1899 if (bfd_link_pic (info))
1900 {
1901 asection *s;
1902 Elf_Internal_Rela outrel;
1903
1904 /* We need to generate a R_RISCV_RELATIVE reloc
1905 for the dynamic linker. */
1906 s = htab->elf.srelgot;
1907 BFD_ASSERT (s != NULL);
1908
1909 outrel.r_offset = sec_addr (htab->elf.sgot) + off;
1910 outrel.r_info =
1911 ELFNN_R_INFO (0, R_RISCV_RELATIVE);
1912 outrel.r_addend = relocation;
1913 relocation = 0;
1914 riscv_elf_append_rela (output_bfd, s, &outrel);
1915 }
1916
1917 bfd_put_NN (output_bfd, relocation,
1918 htab->elf.sgot->contents + off);
1919 local_got_offsets[r_symndx] |= 1;
1920 }
1921 }
1922 relocation = sec_addr (htab->elf.sgot) + off;
1923 absolute = riscv_zero_pcrel_hi_reloc (rel,
1924 info,
1925 pc,
1926 relocation,
1927 contents,
1928 howto,
1929 input_bfd);
1930 r_type = ELFNN_R_TYPE (rel->r_info);
1931 howto = riscv_elf_rtype_to_howto (input_bfd, r_type);
1932 if (howto == NULL)
1933 r = bfd_reloc_notsupported;
1934 else if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc,
1935 relocation, absolute))
1936 r = bfd_reloc_overflow;
1937 break;
1938
1939 case R_RISCV_ADD8:
1940 case R_RISCV_ADD16:
1941 case R_RISCV_ADD32:
1942 case R_RISCV_ADD64:
1943 {
1944 bfd_vma old_value = bfd_get (howto->bitsize, input_bfd,
1945 contents + rel->r_offset);
1946 relocation = old_value + relocation;
1947 }
1948 break;
1949
1950 case R_RISCV_SUB6:
1951 case R_RISCV_SUB8:
1952 case R_RISCV_SUB16:
1953 case R_RISCV_SUB32:
1954 case R_RISCV_SUB64:
1955 {
1956 bfd_vma old_value = bfd_get (howto->bitsize, input_bfd,
1957 contents + rel->r_offset);
1958 relocation = old_value - relocation;
1959 }
1960 break;
1961
1962 case R_RISCV_CALL:
1963 /* Handle a call to an undefined weak function. This won't be
1964 relaxed, so we have to handle it here. */
1965 if (h != NULL && h->root.type == bfd_link_hash_undefweak
1966 && h->plt.offset == MINUS_ONE)
1967 {
1968 /* We can use x0 as the base register. */
1969 bfd_vma insn = bfd_get_32 (input_bfd,
1970 contents + rel->r_offset + 4);
1971 insn &= ~(OP_MASK_RS1 << OP_SH_RS1);
1972 bfd_put_32 (input_bfd, insn, contents + rel->r_offset + 4);
1973 /* Set the relocation value so that we get 0 after the pc
1974 relative adjustment. */
1975 relocation = sec_addr (input_section) + rel->r_offset;
1976 }
1977 /* Fall through. */
1978
1979 case R_RISCV_CALL_PLT:
1980 case R_RISCV_JAL:
1981 case R_RISCV_RVC_JUMP:
1982 if (bfd_link_pic (info) && h != NULL && h->plt.offset != MINUS_ONE)
1983 {
1984 /* Refer to the PLT entry. */
1985 relocation = sec_addr (htab->elf.splt) + h->plt.offset;
1986 unresolved_reloc = FALSE;
1987 }
1988 break;
1989
1990 case R_RISCV_TPREL_HI20:
1991 relocation = tpoff (info, relocation);
1992 break;
1993
1994 case R_RISCV_TPREL_LO12_I:
1995 case R_RISCV_TPREL_LO12_S:
1996 relocation = tpoff (info, relocation);
1997 break;
1998
1999 case R_RISCV_TPREL_I:
2000 case R_RISCV_TPREL_S:
2001 relocation = tpoff (info, relocation);
2002 if (VALID_ITYPE_IMM (relocation + rel->r_addend))
2003 {
2004 /* We can use tp as the base register. */
2005 bfd_vma insn = bfd_get_32 (input_bfd, contents + rel->r_offset);
2006 insn &= ~(OP_MASK_RS1 << OP_SH_RS1);
2007 insn |= X_TP << OP_SH_RS1;
2008 bfd_put_32 (input_bfd, insn, contents + rel->r_offset);
2009 }
2010 else
2011 r = bfd_reloc_overflow;
2012 break;
2013
2014 case R_RISCV_GPREL_I:
2015 case R_RISCV_GPREL_S:
2016 {
2017 bfd_vma gp = riscv_global_pointer_value (info);
2018 bfd_boolean x0_base = VALID_ITYPE_IMM (relocation + rel->r_addend);
2019 if (x0_base || VALID_ITYPE_IMM (relocation + rel->r_addend - gp))
2020 {
2021 /* We can use x0 or gp as the base register. */
2022 bfd_vma insn = bfd_get_32 (input_bfd, contents + rel->r_offset);
2023 insn &= ~(OP_MASK_RS1 << OP_SH_RS1);
2024 if (!x0_base)
2025 {
2026 rel->r_addend -= gp;
2027 insn |= X_GP << OP_SH_RS1;
2028 }
2029 bfd_put_32 (input_bfd, insn, contents + rel->r_offset);
2030 }
2031 else
2032 r = bfd_reloc_overflow;
2033 break;
2034 }
2035
2036 case R_RISCV_PCREL_HI20:
2037 absolute = riscv_zero_pcrel_hi_reloc (rel,
2038 info,
2039 pc,
2040 relocation,
2041 contents,
2042 howto,
2043 input_bfd);
2044 r_type = ELFNN_R_TYPE (rel->r_info);
2045 howto = riscv_elf_rtype_to_howto (input_bfd, r_type);
2046 if (howto == NULL)
2047 r = bfd_reloc_notsupported;
2048 else if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc,
2049 relocation + rel->r_addend,
2050 absolute))
2051 r = bfd_reloc_overflow;
2052 break;
2053
2054 case R_RISCV_PCREL_LO12_I:
2055 case R_RISCV_PCREL_LO12_S:
2056 /* We don't allow section symbols plus addends as the auipc address,
2057 because then riscv_relax_delete_bytes would have to search through
2058 all relocs to update these addends. This is also ambiguous, as
2059 we do allow offsets to be added to the target address, which are
2060 not to be used to find the auipc address. */
2061 if ((ELF_ST_TYPE (sym->st_info) == STT_SECTION) && rel->r_addend)
2062 {
2063 r = bfd_reloc_dangerous;
2064 break;
2065 }
2066
2067 if (riscv_record_pcrel_lo_reloc (&pcrel_relocs, input_section, info,
2068 howto, rel, relocation, name,
2069 contents))
2070 continue;
2071 r = bfd_reloc_overflow;
2072 break;
2073
2074 case R_RISCV_TLS_DTPREL32:
2075 case R_RISCV_TLS_DTPREL64:
2076 relocation = dtpoff (info, relocation);
2077 break;
2078
2079 case R_RISCV_32:
2080 case R_RISCV_64:
2081 if ((input_section->flags & SEC_ALLOC) == 0)
2082 break;
2083
2084 if ((bfd_link_pic (info)
2085 && (h == NULL
2086 || (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2087 && !resolved_to_zero)
2088 || h->root.type != bfd_link_hash_undefweak)
2089 && (! howto->pc_relative
2090 || !SYMBOL_CALLS_LOCAL (info, h)))
2091 || (!bfd_link_pic (info)
2092 && h != NULL
2093 && h->dynindx != -1
2094 && !h->non_got_ref
2095 && ((h->def_dynamic
2096 && !h->def_regular)
2097 || h->root.type == bfd_link_hash_undefweak
2098 || h->root.type == bfd_link_hash_undefined)))
2099 {
2100 Elf_Internal_Rela outrel;
2101 bfd_boolean skip_static_relocation, skip_dynamic_relocation;
2102
2103 /* When generating a shared object, these relocations
2104 are copied into the output file to be resolved at run
2105 time. */
2106
2107 outrel.r_offset =
2108 _bfd_elf_section_offset (output_bfd, info, input_section,
2109 rel->r_offset);
2110 skip_static_relocation = outrel.r_offset != (bfd_vma) -2;
2111 skip_dynamic_relocation = outrel.r_offset >= (bfd_vma) -2;
2112 outrel.r_offset += sec_addr (input_section);
2113
2114 if (skip_dynamic_relocation)
2115 memset (&outrel, 0, sizeof outrel);
2116 else if (h != NULL && h->dynindx != -1
2117 && !(bfd_link_pic (info)
2118 && SYMBOLIC_BIND (info, h)
2119 && h->def_regular))
2120 {
2121 outrel.r_info = ELFNN_R_INFO (h->dynindx, r_type);
2122 outrel.r_addend = rel->r_addend;
2123 }
2124 else
2125 {
2126 outrel.r_info = ELFNN_R_INFO (0, R_RISCV_RELATIVE);
2127 outrel.r_addend = relocation + rel->r_addend;
2128 }
2129
2130 riscv_elf_append_rela (output_bfd, sreloc, &outrel);
2131 if (skip_static_relocation)
2132 continue;
2133 }
2134 break;
2135
2136 case R_RISCV_TLS_GOT_HI20:
2137 is_ie = TRUE;
2138 /* Fall through. */
2139
2140 case R_RISCV_TLS_GD_HI20:
2141 if (h != NULL)
2142 {
2143 off = h->got.offset;
2144 h->got.offset |= 1;
2145 }
2146 else
2147 {
2148 off = local_got_offsets[r_symndx];
2149 local_got_offsets[r_symndx] |= 1;
2150 }
2151
2152 tls_type = _bfd_riscv_elf_tls_type (input_bfd, h, r_symndx);
2153 BFD_ASSERT (tls_type & (GOT_TLS_IE | GOT_TLS_GD));
2154 /* If this symbol is referenced by both GD and IE TLS, the IE
2155 reference's GOT slot follows the GD reference's slots. */
2156 ie_off = 0;
2157 if ((tls_type & GOT_TLS_GD) && (tls_type & GOT_TLS_IE))
2158 ie_off = 2 * GOT_ENTRY_SIZE;
2159
2160 if ((off & 1) != 0)
2161 off &= ~1;
2162 else
2163 {
2164 Elf_Internal_Rela outrel;
2165 int indx = 0;
2166 bfd_boolean need_relocs = FALSE;
2167
2168 if (htab->elf.srelgot == NULL)
2169 abort ();
2170
2171 if (h != NULL)
2172 {
2173 bfd_boolean dyn, pic;
2174 dyn = htab->elf.dynamic_sections_created;
2175 pic = bfd_link_pic (info);
2176
2177 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, pic, h)
2178 && (!pic || !SYMBOL_REFERENCES_LOCAL (info, h)))
2179 indx = h->dynindx;
2180 }
2181
2182 /* The GOT entries have not been initialized yet. Do it
2183 now, and emit any relocations. */
2184 if ((bfd_link_pic (info) || indx != 0)
2185 && (h == NULL
2186 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2187 || h->root.type != bfd_link_hash_undefweak))
2188 need_relocs = TRUE;
2189
2190 if (tls_type & GOT_TLS_GD)
2191 {
2192 if (need_relocs)
2193 {
2194 outrel.r_offset = sec_addr (htab->elf.sgot) + off;
2195 outrel.r_addend = 0;
2196 outrel.r_info = ELFNN_R_INFO (indx, R_RISCV_TLS_DTPMODNN);
2197 bfd_put_NN (output_bfd, 0,
2198 htab->elf.sgot->contents + off);
2199 riscv_elf_append_rela (output_bfd, htab->elf.srelgot, &outrel);
2200 if (indx == 0)
2201 {
2202 BFD_ASSERT (! unresolved_reloc);
2203 bfd_put_NN (output_bfd,
2204 dtpoff (info, relocation),
2205 (htab->elf.sgot->contents + off +
2206 RISCV_ELF_WORD_BYTES));
2207 }
2208 else
2209 {
2210 bfd_put_NN (output_bfd, 0,
2211 (htab->elf.sgot->contents + off +
2212 RISCV_ELF_WORD_BYTES));
2213 outrel.r_info = ELFNN_R_INFO (indx, R_RISCV_TLS_DTPRELNN);
2214 outrel.r_offset += RISCV_ELF_WORD_BYTES;
2215 riscv_elf_append_rela (output_bfd, htab->elf.srelgot, &outrel);
2216 }
2217 }
2218 else
2219 {
2220 /* If we are not emitting relocations for a
2221 general dynamic reference, then we must be in a
2222 static link or an executable link with the
2223 symbol binding locally. Mark it as belonging
2224 to module 1, the executable. */
2225 bfd_put_NN (output_bfd, 1,
2226 htab->elf.sgot->contents + off);
2227 bfd_put_NN (output_bfd,
2228 dtpoff (info, relocation),
2229 (htab->elf.sgot->contents + off +
2230 RISCV_ELF_WORD_BYTES));
2231 }
2232 }
2233
2234 if (tls_type & GOT_TLS_IE)
2235 {
2236 if (need_relocs)
2237 {
2238 bfd_put_NN (output_bfd, 0,
2239 htab->elf.sgot->contents + off + ie_off);
2240 outrel.r_offset = sec_addr (htab->elf.sgot)
2241 + off + ie_off;
2242 outrel.r_addend = 0;
2243 if (indx == 0)
2244 outrel.r_addend = tpoff (info, relocation);
2245 outrel.r_info = ELFNN_R_INFO (indx, R_RISCV_TLS_TPRELNN);
2246 riscv_elf_append_rela (output_bfd, htab->elf.srelgot, &outrel);
2247 }
2248 else
2249 {
2250 bfd_put_NN (output_bfd, tpoff (info, relocation),
2251 htab->elf.sgot->contents + off + ie_off);
2252 }
2253 }
2254 }
2255
2256 BFD_ASSERT (off < (bfd_vma) -2);
2257 relocation = sec_addr (htab->elf.sgot) + off + (is_ie ? ie_off : 0);
2258 if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc,
2259 relocation, FALSE))
2260 r = bfd_reloc_overflow;
2261 unresolved_reloc = FALSE;
2262 break;
2263
2264 default:
2265 r = bfd_reloc_notsupported;
2266 }
2267
2268 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2269 because such sections are not SEC_ALLOC and thus ld.so will
2270 not process them. */
2271 if (unresolved_reloc
2272 && !((input_section->flags & SEC_DEBUGGING) != 0
2273 && h->def_dynamic)
2274 && _bfd_elf_section_offset (output_bfd, info, input_section,
2275 rel->r_offset) != (bfd_vma) -1)
2276 {
2277 (*_bfd_error_handler)
2278 (_("%pB(%pA+%#" PRIx64 "): "
2279 "unresolvable %s relocation against symbol `%s'"),
2280 input_bfd,
2281 input_section,
2282 (uint64_t) rel->r_offset,
2283 howto->name,
2284 h->root.root.string);
2285 continue;
2286 }
2287
2288 if (r == bfd_reloc_ok)
2289 r = perform_relocation (howto, rel, relocation, input_section,
2290 input_bfd, contents);
2291
2292 switch (r)
2293 {
2294 case bfd_reloc_ok:
2295 continue;
2296
2297 case bfd_reloc_overflow:
2298 info->callbacks->reloc_overflow
2299 (info, (h ? &h->root : NULL), name, howto->name,
2300 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
2301 break;
2302
2303 case bfd_reloc_undefined:
2304 info->callbacks->undefined_symbol
2305 (info, name, input_bfd, input_section, rel->r_offset,
2306 TRUE);
2307 break;
2308
2309 case bfd_reloc_outofrange:
2310 msg = _("%X%P: internal error: out of range error\n");
2311 break;
2312
2313 case bfd_reloc_notsupported:
2314 msg = _("%X%P: internal error: unsupported relocation error\n");
2315 break;
2316
2317 case bfd_reloc_dangerous:
2318 info->callbacks->reloc_dangerous
2319 (info, "%pcrel_lo section symbol with an addend", input_bfd,
2320 input_section, rel->r_offset);
2321 break;
2322
2323 default:
2324 msg = _("%X%P: internal error: unknown error\n");
2325 break;
2326 }
2327
2328 if (msg)
2329 info->callbacks->einfo (msg);
2330
2331 /* We already reported the error via a callback, so don't try to report
2332 it again by returning false. That leads to spurious errors. */
2333 ret = TRUE;
2334 goto out;
2335 }
2336
2337 ret = riscv_resolve_pcrel_lo_relocs (&pcrel_relocs);
2338 out:
2339 riscv_free_pcrel_relocs (&pcrel_relocs);
2340 return ret;
2341 }
2342
2343 /* Finish up dynamic symbol handling. We set the contents of various
2344 dynamic sections here. */
2345
2346 static bfd_boolean
2347 riscv_elf_finish_dynamic_symbol (bfd *output_bfd,
2348 struct bfd_link_info *info,
2349 struct elf_link_hash_entry *h,
2350 Elf_Internal_Sym *sym)
2351 {
2352 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info);
2353 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
2354
2355 if (h->plt.offset != (bfd_vma) -1)
2356 {
2357 /* We've decided to create a PLT entry for this symbol. */
2358 bfd_byte *loc;
2359 bfd_vma i, header_address, plt_idx, got_address;
2360 uint32_t plt_entry[PLT_ENTRY_INSNS];
2361 Elf_Internal_Rela rela;
2362
2363 BFD_ASSERT (h->dynindx != -1);
2364
2365 /* Calculate the address of the PLT header. */
2366 header_address = sec_addr (htab->elf.splt);
2367
2368 /* Calculate the index of the entry. */
2369 plt_idx = (h->plt.offset - PLT_HEADER_SIZE) / PLT_ENTRY_SIZE;
2370
2371 /* Calculate the address of the .got.plt entry. */
2372 got_address = riscv_elf_got_plt_val (plt_idx, info);
2373
2374 /* Find out where the .plt entry should go. */
2375 loc = htab->elf.splt->contents + h->plt.offset;
2376
2377 /* Fill in the PLT entry itself. */
2378 if (! riscv_make_plt_entry (output_bfd, got_address,
2379 header_address + h->plt.offset,
2380 plt_entry))
2381 return FALSE;
2382
2383 for (i = 0; i < PLT_ENTRY_INSNS; i++)
2384 bfd_put_32 (output_bfd, plt_entry[i], loc + 4*i);
2385
2386 /* Fill in the initial value of the .got.plt entry. */
2387 loc = htab->elf.sgotplt->contents
2388 + (got_address - sec_addr (htab->elf.sgotplt));
2389 bfd_put_NN (output_bfd, sec_addr (htab->elf.splt), loc);
2390
2391 /* Fill in the entry in the .rela.plt section. */
2392 rela.r_offset = got_address;
2393 rela.r_addend = 0;
2394 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_JUMP_SLOT);
2395
2396 loc = htab->elf.srelplt->contents + plt_idx * sizeof (ElfNN_External_Rela);
2397 bed->s->swap_reloca_out (output_bfd, &rela, loc);
2398
2399 if (!h->def_regular)
2400 {
2401 /* Mark the symbol as undefined, rather than as defined in
2402 the .plt section. Leave the value alone. */
2403 sym->st_shndx = SHN_UNDEF;
2404 /* If the symbol is weak, we do need to clear the value.
2405 Otherwise, the PLT entry would provide a definition for
2406 the symbol even if the symbol wasn't defined anywhere,
2407 and so the symbol would never be NULL. */
2408 if (!h->ref_regular_nonweak)
2409 sym->st_value = 0;
2410 }
2411 }
2412
2413 if (h->got.offset != (bfd_vma) -1
2414 && !(riscv_elf_hash_entry (h)->tls_type & (GOT_TLS_GD | GOT_TLS_IE))
2415 && !UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
2416 {
2417 asection *sgot;
2418 asection *srela;
2419 Elf_Internal_Rela rela;
2420
2421 /* This symbol has an entry in the GOT. Set it up. */
2422
2423 sgot = htab->elf.sgot;
2424 srela = htab->elf.srelgot;
2425 BFD_ASSERT (sgot != NULL && srela != NULL);
2426
2427 rela.r_offset = sec_addr (sgot) + (h->got.offset &~ (bfd_vma) 1);
2428
2429 /* If this is a local symbol reference, we just want to emit a RELATIVE
2430 reloc. This can happen if it is a -Bsymbolic link, or a pie link, or
2431 the symbol was forced to be local because of a version file.
2432 The entry in the global offset table will already have been
2433 initialized in the relocate_section function. */
2434 if (bfd_link_pic (info)
2435 && SYMBOL_REFERENCES_LOCAL (info, h))
2436 {
2437 BFD_ASSERT((h->got.offset & 1) != 0);
2438 asection *sec = h->root.u.def.section;
2439 rela.r_info = ELFNN_R_INFO (0, R_RISCV_RELATIVE);
2440 rela.r_addend = (h->root.u.def.value
2441 + sec->output_section->vma
2442 + sec->output_offset);
2443 }
2444 else
2445 {
2446 BFD_ASSERT((h->got.offset & 1) == 0);
2447 BFD_ASSERT (h->dynindx != -1);
2448 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_NN);
2449 rela.r_addend = 0;
2450 }
2451
2452 bfd_put_NN (output_bfd, 0,
2453 sgot->contents + (h->got.offset & ~(bfd_vma) 1));
2454 riscv_elf_append_rela (output_bfd, srela, &rela);
2455 }
2456
2457 if (h->needs_copy)
2458 {
2459 Elf_Internal_Rela rela;
2460 asection *s;
2461
2462 /* This symbols needs a copy reloc. Set it up. */
2463 BFD_ASSERT (h->dynindx != -1);
2464
2465 rela.r_offset = sec_addr (h->root.u.def.section) + h->root.u.def.value;
2466 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_COPY);
2467 rela.r_addend = 0;
2468 if (h->root.u.def.section == htab->elf.sdynrelro)
2469 s = htab->elf.sreldynrelro;
2470 else
2471 s = htab->elf.srelbss;
2472 riscv_elf_append_rela (output_bfd, s, &rela);
2473 }
2474
2475 /* Mark some specially defined symbols as absolute. */
2476 if (h == htab->elf.hdynamic
2477 || (h == htab->elf.hgot || h == htab->elf.hplt))
2478 sym->st_shndx = SHN_ABS;
2479
2480 return TRUE;
2481 }
2482
2483 /* Finish up the dynamic sections. */
2484
2485 static bfd_boolean
2486 riscv_finish_dyn (bfd *output_bfd, struct bfd_link_info *info,
2487 bfd *dynobj, asection *sdyn)
2488 {
2489 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info);
2490 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
2491 size_t dynsize = bed->s->sizeof_dyn;
2492 bfd_byte *dyncon, *dynconend;
2493
2494 dynconend = sdyn->contents + sdyn->size;
2495 for (dyncon = sdyn->contents; dyncon < dynconend; dyncon += dynsize)
2496 {
2497 Elf_Internal_Dyn dyn;
2498 asection *s;
2499
2500 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
2501
2502 switch (dyn.d_tag)
2503 {
2504 case DT_PLTGOT:
2505 s = htab->elf.sgotplt;
2506 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
2507 break;
2508 case DT_JMPREL:
2509 s = htab->elf.srelplt;
2510 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
2511 break;
2512 case DT_PLTRELSZ:
2513 s = htab->elf.srelplt;
2514 dyn.d_un.d_val = s->size;
2515 break;
2516 default:
2517 continue;
2518 }
2519
2520 bed->s->swap_dyn_out (output_bfd, &dyn, dyncon);
2521 }
2522 return TRUE;
2523 }
2524
2525 static bfd_boolean
2526 riscv_elf_finish_dynamic_sections (bfd *output_bfd,
2527 struct bfd_link_info *info)
2528 {
2529 bfd *dynobj;
2530 asection *sdyn;
2531 struct riscv_elf_link_hash_table *htab;
2532
2533 htab = riscv_elf_hash_table (info);
2534 BFD_ASSERT (htab != NULL);
2535 dynobj = htab->elf.dynobj;
2536
2537 sdyn = bfd_get_linker_section (dynobj, ".dynamic");
2538
2539 if (elf_hash_table (info)->dynamic_sections_created)
2540 {
2541 asection *splt;
2542 bfd_boolean ret;
2543
2544 splt = htab->elf.splt;
2545 BFD_ASSERT (splt != NULL && sdyn != NULL);
2546
2547 ret = riscv_finish_dyn (output_bfd, info, dynobj, sdyn);
2548
2549 if (!ret)
2550 return ret;
2551
2552 /* Fill in the head and tail entries in the procedure linkage table. */
2553 if (splt->size > 0)
2554 {
2555 int i;
2556 uint32_t plt_header[PLT_HEADER_INSNS];
2557 ret = riscv_make_plt_header (output_bfd,
2558 sec_addr (htab->elf.sgotplt),
2559 sec_addr (splt), plt_header);
2560 if (!ret)
2561 return ret;
2562
2563 for (i = 0; i < PLT_HEADER_INSNS; i++)
2564 bfd_put_32 (output_bfd, plt_header[i], splt->contents + 4*i);
2565
2566 elf_section_data (splt->output_section)->this_hdr.sh_entsize
2567 = PLT_ENTRY_SIZE;
2568 }
2569 }
2570
2571 if (htab->elf.sgotplt)
2572 {
2573 asection *output_section = htab->elf.sgotplt->output_section;
2574
2575 if (bfd_is_abs_section (output_section))
2576 {
2577 (*_bfd_error_handler)
2578 (_("discarded output section: `%pA'"), htab->elf.sgotplt);
2579 return FALSE;
2580 }
2581
2582 if (htab->elf.sgotplt->size > 0)
2583 {
2584 /* Write the first two entries in .got.plt, needed for the dynamic
2585 linker. */
2586 bfd_put_NN (output_bfd, (bfd_vma) -1, htab->elf.sgotplt->contents);
2587 bfd_put_NN (output_bfd, (bfd_vma) 0,
2588 htab->elf.sgotplt->contents + GOT_ENTRY_SIZE);
2589 }
2590
2591 elf_section_data (output_section)->this_hdr.sh_entsize = GOT_ENTRY_SIZE;
2592 }
2593
2594 if (htab->elf.sgot)
2595 {
2596 asection *output_section = htab->elf.sgot->output_section;
2597
2598 if (htab->elf.sgot->size > 0)
2599 {
2600 /* Set the first entry in the global offset table to the address of
2601 the dynamic section. */
2602 bfd_vma val = sdyn ? sec_addr (sdyn) : 0;
2603 bfd_put_NN (output_bfd, val, htab->elf.sgot->contents);
2604 }
2605
2606 elf_section_data (output_section)->this_hdr.sh_entsize = GOT_ENTRY_SIZE;
2607 }
2608
2609 return TRUE;
2610 }
2611
2612 /* Return address for Ith PLT stub in section PLT, for relocation REL
2613 or (bfd_vma) -1 if it should not be included. */
2614
2615 static bfd_vma
2616 riscv_elf_plt_sym_val (bfd_vma i, const asection *plt,
2617 const arelent *rel ATTRIBUTE_UNUSED)
2618 {
2619 return plt->vma + PLT_HEADER_SIZE + i * PLT_ENTRY_SIZE;
2620 }
2621
2622 static enum elf_reloc_type_class
2623 riscv_reloc_type_class (const struct bfd_link_info *info ATTRIBUTE_UNUSED,
2624 const asection *rel_sec ATTRIBUTE_UNUSED,
2625 const Elf_Internal_Rela *rela)
2626 {
2627 switch (ELFNN_R_TYPE (rela->r_info))
2628 {
2629 case R_RISCV_RELATIVE:
2630 return reloc_class_relative;
2631 case R_RISCV_JUMP_SLOT:
2632 return reloc_class_plt;
2633 case R_RISCV_COPY:
2634 return reloc_class_copy;
2635 default:
2636 return reloc_class_normal;
2637 }
2638 }
2639
2640 /* Merge backend specific data from an object file to the output
2641 object file when linking. */
2642
2643 static bfd_boolean
2644 _bfd_riscv_elf_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)
2645 {
2646 bfd *obfd = info->output_bfd;
2647 flagword new_flags = elf_elfheader (ibfd)->e_flags;
2648 flagword old_flags = elf_elfheader (obfd)->e_flags;
2649
2650 if (!is_riscv_elf (ibfd) || !is_riscv_elf (obfd))
2651 return TRUE;
2652
2653 if (strcmp (bfd_get_target (ibfd), bfd_get_target (obfd)) != 0)
2654 {
2655 (*_bfd_error_handler)
2656 (_("%pB: ABI is incompatible with that of the selected emulation:\n"
2657 " target emulation `%s' does not match `%s'"),
2658 ibfd, bfd_get_target (ibfd), bfd_get_target (obfd));
2659 return FALSE;
2660 }
2661
2662 if (!_bfd_elf_merge_object_attributes (ibfd, info))
2663 return FALSE;
2664
2665 if (! elf_flags_init (obfd))
2666 {
2667 elf_flags_init (obfd) = TRUE;
2668 elf_elfheader (obfd)->e_flags = new_flags;
2669 return TRUE;
2670 }
2671
2672 /* Disallow linking different float ABIs. */
2673 if ((old_flags ^ new_flags) & EF_RISCV_FLOAT_ABI)
2674 {
2675 (*_bfd_error_handler)
2676 (_("%pB: can't link hard-float modules with soft-float modules"), ibfd);
2677 goto fail;
2678 }
2679
2680 /* Disallow linking RVE and non-RVE. */
2681 if ((old_flags ^ new_flags) & EF_RISCV_RVE)
2682 {
2683 (*_bfd_error_handler)
2684 (_("%pB: can't link RVE with other target"), ibfd);
2685 goto fail;
2686 }
2687
2688 /* Allow linking RVC and non-RVC, and keep the RVC flag. */
2689 elf_elfheader (obfd)->e_flags |= new_flags & EF_RISCV_RVC;
2690
2691 return TRUE;
2692
2693 fail:
2694 bfd_set_error (bfd_error_bad_value);
2695 return FALSE;
2696 }
2697
2698 /* Delete some bytes from a section while relaxing. */
2699
2700 static bfd_boolean
2701 riscv_relax_delete_bytes (bfd *abfd, asection *sec, bfd_vma addr, size_t count,
2702 struct bfd_link_info *link_info)
2703 {
2704 unsigned int i, symcount;
2705 bfd_vma toaddr = sec->size;
2706 struct elf_link_hash_entry **sym_hashes = elf_sym_hashes (abfd);
2707 Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2708 unsigned int sec_shndx = _bfd_elf_section_from_bfd_section (abfd, sec);
2709 struct bfd_elf_section_data *data = elf_section_data (sec);
2710 bfd_byte *contents = data->this_hdr.contents;
2711
2712 /* Actually delete the bytes. */
2713 sec->size -= count;
2714 memmove (contents + addr, contents + addr + count, toaddr - addr - count);
2715
2716 /* Adjust the location of all of the relocs. Note that we need not
2717 adjust the addends, since all PC-relative references must be against
2718 symbols, which we will adjust below. */
2719 for (i = 0; i < sec->reloc_count; i++)
2720 if (data->relocs[i].r_offset > addr && data->relocs[i].r_offset < toaddr)
2721 data->relocs[i].r_offset -= count;
2722
2723 /* Adjust the local symbols defined in this section. */
2724 for (i = 0; i < symtab_hdr->sh_info; i++)
2725 {
2726 Elf_Internal_Sym *sym = (Elf_Internal_Sym *) symtab_hdr->contents + i;
2727 if (sym->st_shndx == sec_shndx)
2728 {
2729 /* If the symbol is in the range of memory we just moved, we
2730 have to adjust its value. */
2731 if (sym->st_value > addr && sym->st_value <= toaddr)
2732 sym->st_value -= count;
2733
2734 /* If the symbol *spans* the bytes we just deleted (i.e. its
2735 *end* is in the moved bytes but its *start* isn't), then we
2736 must adjust its size.
2737
2738 This test needs to use the original value of st_value, otherwise
2739 we might accidentally decrease size when deleting bytes right
2740 before the symbol. But since deleted relocs can't span across
2741 symbols, we can't have both a st_value and a st_size decrease,
2742 so it is simpler to just use an else. */
2743 else if (sym->st_value <= addr
2744 && sym->st_value + sym->st_size > addr
2745 && sym->st_value + sym->st_size <= toaddr)
2746 sym->st_size -= count;
2747 }
2748 }
2749
2750 /* Now adjust the global symbols defined in this section. */
2751 symcount = ((symtab_hdr->sh_size / sizeof (ElfNN_External_Sym))
2752 - symtab_hdr->sh_info);
2753
2754 for (i = 0; i < symcount; i++)
2755 {
2756 struct elf_link_hash_entry *sym_hash = sym_hashes[i];
2757
2758 /* The '--wrap SYMBOL' option is causing a pain when the object file,
2759 containing the definition of __wrap_SYMBOL, includes a direct
2760 call to SYMBOL as well. Since both __wrap_SYMBOL and SYMBOL reference
2761 the same symbol (which is __wrap_SYMBOL), but still exist as two
2762 different symbols in 'sym_hashes', we don't want to adjust
2763 the global symbol __wrap_SYMBOL twice. */
2764 /* The same problem occurs with symbols that are versioned_hidden, as
2765 foo becomes an alias for foo@BAR, and hence they need the same
2766 treatment. */
2767 if (link_info->wrap_hash != NULL
2768 || sym_hash->versioned == versioned_hidden)
2769 {
2770 struct elf_link_hash_entry **cur_sym_hashes;
2771
2772 /* Loop only over the symbols which have already been checked. */
2773 for (cur_sym_hashes = sym_hashes; cur_sym_hashes < &sym_hashes[i];
2774 cur_sym_hashes++)
2775 {
2776 /* If the current symbol is identical to 'sym_hash', that means
2777 the symbol was already adjusted (or at least checked). */
2778 if (*cur_sym_hashes == sym_hash)
2779 break;
2780 }
2781 /* Don't adjust the symbol again. */
2782 if (cur_sym_hashes < &sym_hashes[i])
2783 continue;
2784 }
2785
2786 if ((sym_hash->root.type == bfd_link_hash_defined
2787 || sym_hash->root.type == bfd_link_hash_defweak)
2788 && sym_hash->root.u.def.section == sec)
2789 {
2790 /* As above, adjust the value if needed. */
2791 if (sym_hash->root.u.def.value > addr
2792 && sym_hash->root.u.def.value <= toaddr)
2793 sym_hash->root.u.def.value -= count;
2794
2795 /* As above, adjust the size if needed. */
2796 else if (sym_hash->root.u.def.value <= addr
2797 && sym_hash->root.u.def.value + sym_hash->size > addr
2798 && sym_hash->root.u.def.value + sym_hash->size <= toaddr)
2799 sym_hash->size -= count;
2800 }
2801 }
2802
2803 return TRUE;
2804 }
2805
2806 /* A second format for recording PC-relative hi relocations. This stores the
2807 information required to relax them to GP-relative addresses. */
2808
2809 typedef struct riscv_pcgp_hi_reloc riscv_pcgp_hi_reloc;
2810 struct riscv_pcgp_hi_reloc
2811 {
2812 bfd_vma hi_sec_off;
2813 bfd_vma hi_addend;
2814 bfd_vma hi_addr;
2815 unsigned hi_sym;
2816 asection *sym_sec;
2817 riscv_pcgp_hi_reloc *next;
2818 };
2819
2820 typedef struct riscv_pcgp_lo_reloc riscv_pcgp_lo_reloc;
2821 struct riscv_pcgp_lo_reloc
2822 {
2823 bfd_vma hi_sec_off;
2824 riscv_pcgp_lo_reloc *next;
2825 };
2826
2827 typedef struct
2828 {
2829 riscv_pcgp_hi_reloc *hi;
2830 riscv_pcgp_lo_reloc *lo;
2831 } riscv_pcgp_relocs;
2832
2833 /* Initialize the pcgp reloc info in P. */
2834
2835 static bfd_boolean
2836 riscv_init_pcgp_relocs (riscv_pcgp_relocs *p)
2837 {
2838 p->hi = NULL;
2839 p->lo = NULL;
2840 return TRUE;
2841 }
2842
2843 /* Free the pcgp reloc info in P. */
2844
2845 static void
2846 riscv_free_pcgp_relocs (riscv_pcgp_relocs *p,
2847 bfd *abfd ATTRIBUTE_UNUSED,
2848 asection *sec ATTRIBUTE_UNUSED)
2849 {
2850 riscv_pcgp_hi_reloc *c;
2851 riscv_pcgp_lo_reloc *l;
2852
2853 for (c = p->hi; c != NULL;)
2854 {
2855 riscv_pcgp_hi_reloc *next = c->next;
2856 free (c);
2857 c = next;
2858 }
2859
2860 for (l = p->lo; l != NULL;)
2861 {
2862 riscv_pcgp_lo_reloc *next = l->next;
2863 free (l);
2864 l = next;
2865 }
2866 }
2867
2868 /* Record pcgp hi part reloc info in P, using HI_SEC_OFF as the lookup index.
2869 The HI_ADDEND, HI_ADDR, HI_SYM, and SYM_SEC args contain info required to
2870 relax the corresponding lo part reloc. */
2871
2872 static bfd_boolean
2873 riscv_record_pcgp_hi_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off,
2874 bfd_vma hi_addend, bfd_vma hi_addr,
2875 unsigned hi_sym, asection *sym_sec)
2876 {
2877 riscv_pcgp_hi_reloc *new = bfd_malloc (sizeof(*new));
2878 if (!new)
2879 return FALSE;
2880 new->hi_sec_off = hi_sec_off;
2881 new->hi_addend = hi_addend;
2882 new->hi_addr = hi_addr;
2883 new->hi_sym = hi_sym;
2884 new->sym_sec = sym_sec;
2885 new->next = p->hi;
2886 p->hi = new;
2887 return TRUE;
2888 }
2889
2890 /* Look up hi part pcgp reloc info in P, using HI_SEC_OFF as the lookup index.
2891 This is used by a lo part reloc to find the corresponding hi part reloc. */
2892
2893 static riscv_pcgp_hi_reloc *
2894 riscv_find_pcgp_hi_reloc(riscv_pcgp_relocs *p, bfd_vma hi_sec_off)
2895 {
2896 riscv_pcgp_hi_reloc *c;
2897
2898 for (c = p->hi; c != NULL; c = c->next)
2899 if (c->hi_sec_off == hi_sec_off)
2900 return c;
2901 return NULL;
2902 }
2903
2904 /* Record pcgp lo part reloc info in P, using HI_SEC_OFF as the lookup info.
2905 This is used to record relocs that can't be relaxed. */
2906
2907 static bfd_boolean
2908 riscv_record_pcgp_lo_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off)
2909 {
2910 riscv_pcgp_lo_reloc *new = bfd_malloc (sizeof(*new));
2911 if (!new)
2912 return FALSE;
2913 new->hi_sec_off = hi_sec_off;
2914 new->next = p->lo;
2915 p->lo = new;
2916 return TRUE;
2917 }
2918
2919 /* Look up lo part pcgp reloc info in P, using HI_SEC_OFF as the lookup index.
2920 This is used by a hi part reloc to find the corresponding lo part reloc. */
2921
2922 static bfd_boolean
2923 riscv_find_pcgp_lo_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off)
2924 {
2925 riscv_pcgp_lo_reloc *c;
2926
2927 for (c = p->lo; c != NULL; c = c->next)
2928 if (c->hi_sec_off == hi_sec_off)
2929 return TRUE;
2930 return FALSE;
2931 }
2932
2933 typedef bfd_boolean (*relax_func_t) (bfd *, asection *, asection *,
2934 struct bfd_link_info *,
2935 Elf_Internal_Rela *,
2936 bfd_vma, bfd_vma, bfd_vma, bfd_boolean *,
2937 riscv_pcgp_relocs *);
2938
2939 /* Relax AUIPC + JALR into JAL. */
2940
2941 static bfd_boolean
2942 _bfd_riscv_relax_call (bfd *abfd, asection *sec, asection *sym_sec,
2943 struct bfd_link_info *link_info,
2944 Elf_Internal_Rela *rel,
2945 bfd_vma symval,
2946 bfd_vma max_alignment,
2947 bfd_vma reserve_size ATTRIBUTE_UNUSED,
2948 bfd_boolean *again,
2949 riscv_pcgp_relocs *pcgp_relocs ATTRIBUTE_UNUSED)
2950 {
2951 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
2952 bfd_signed_vma foff = symval - (sec_addr (sec) + rel->r_offset);
2953 bfd_boolean near_zero = (symval + RISCV_IMM_REACH/2) < RISCV_IMM_REACH;
2954 bfd_vma auipc, jalr;
2955 int rd, r_type, len = 4, rvc = elf_elfheader (abfd)->e_flags & EF_RISCV_RVC;
2956
2957 /* If the call crosses section boundaries, an alignment directive could
2958 cause the PC-relative offset to later increase. */
2959 if (VALID_UJTYPE_IMM (foff) && sym_sec->output_section != sec->output_section)
2960 foff += (foff < 0 ? -max_alignment : max_alignment);
2961
2962 /* See if this function call can be shortened. */
2963 if (!VALID_UJTYPE_IMM (foff) && !(!bfd_link_pic (link_info) && near_zero))
2964 return TRUE;
2965
2966 /* Shorten the function call. */
2967 BFD_ASSERT (rel->r_offset + 8 <= sec->size);
2968
2969 auipc = bfd_get_32 (abfd, contents + rel->r_offset);
2970 jalr = bfd_get_32 (abfd, contents + rel->r_offset + 4);
2971 rd = (jalr >> OP_SH_RD) & OP_MASK_RD;
2972 rvc = rvc && VALID_RVC_J_IMM (foff) && ARCH_SIZE == 32;
2973
2974 if (rvc && (rd == 0 || rd == X_RA))
2975 {
2976 /* Relax to C.J[AL] rd, addr. */
2977 r_type = R_RISCV_RVC_JUMP;
2978 auipc = rd == 0 ? MATCH_C_J : MATCH_C_JAL;
2979 len = 2;
2980 }
2981 else if (VALID_UJTYPE_IMM (foff))
2982 {
2983 /* Relax to JAL rd, addr. */
2984 r_type = R_RISCV_JAL;
2985 auipc = MATCH_JAL | (rd << OP_SH_RD);
2986 }
2987 else /* near_zero */
2988 {
2989 /* Relax to JALR rd, x0, addr. */
2990 r_type = R_RISCV_LO12_I;
2991 auipc = MATCH_JALR | (rd << OP_SH_RD);
2992 }
2993
2994 /* Replace the R_RISCV_CALL reloc. */
2995 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), r_type);
2996 /* Replace the AUIPC. */
2997 bfd_put (8 * len, abfd, auipc, contents + rel->r_offset);
2998
2999 /* Delete unnecessary JALR. */
3000 *again = TRUE;
3001 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset + len, 8 - len,
3002 link_info);
3003 }
3004
3005 /* Traverse all output sections and return the max alignment. */
3006
3007 static bfd_vma
3008 _bfd_riscv_get_max_alignment (asection *sec)
3009 {
3010 unsigned int max_alignment_power = 0;
3011 asection *o;
3012
3013 for (o = sec->output_section->owner->sections; o != NULL; o = o->next)
3014 {
3015 if (o->alignment_power > max_alignment_power)
3016 max_alignment_power = o->alignment_power;
3017 }
3018
3019 return (bfd_vma) 1 << max_alignment_power;
3020 }
3021
3022 /* Relax non-PIC global variable references. */
3023
3024 static bfd_boolean
3025 _bfd_riscv_relax_lui (bfd *abfd,
3026 asection *sec,
3027 asection *sym_sec,
3028 struct bfd_link_info *link_info,
3029 Elf_Internal_Rela *rel,
3030 bfd_vma symval,
3031 bfd_vma max_alignment,
3032 bfd_vma reserve_size,
3033 bfd_boolean *again,
3034 riscv_pcgp_relocs *pcgp_relocs ATTRIBUTE_UNUSED)
3035 {
3036 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
3037 bfd_vma gp = riscv_global_pointer_value (link_info);
3038 int use_rvc = elf_elfheader (abfd)->e_flags & EF_RISCV_RVC;
3039
3040 /* Mergeable symbols and code might later move out of range. */
3041 if (sym_sec->flags & (SEC_MERGE | SEC_CODE))
3042 return TRUE;
3043
3044 BFD_ASSERT (rel->r_offset + 4 <= sec->size);
3045
3046 if (gp)
3047 {
3048 /* If gp and the symbol are in the same output section, then
3049 consider only that section's alignment. */
3050 struct bfd_link_hash_entry *h =
3051 bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, FALSE, FALSE,
3052 TRUE);
3053 if (h->u.def.section->output_section == sym_sec->output_section)
3054 max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
3055 }
3056
3057 /* Is the reference in range of x0 or gp?
3058 Valid gp range conservatively because of alignment issue. */
3059 if (VALID_ITYPE_IMM (symval)
3060 || (symval >= gp
3061 && VALID_ITYPE_IMM (symval - gp + max_alignment + reserve_size))
3062 || (symval < gp
3063 && VALID_ITYPE_IMM (symval - gp - max_alignment - reserve_size)))
3064 {
3065 unsigned sym = ELFNN_R_SYM (rel->r_info);
3066 switch (ELFNN_R_TYPE (rel->r_info))
3067 {
3068 case R_RISCV_LO12_I:
3069 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_I);
3070 return TRUE;
3071
3072 case R_RISCV_LO12_S:
3073 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_S);
3074 return TRUE;
3075
3076 case R_RISCV_HI20:
3077 /* We can delete the unnecessary LUI and reloc. */
3078 rel->r_info = ELFNN_R_INFO (0, R_RISCV_NONE);
3079 *again = TRUE;
3080 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset, 4,
3081 link_info);
3082
3083 default:
3084 abort ();
3085 }
3086 }
3087
3088 /* Can we relax LUI to C.LUI? Alignment might move the section forward;
3089 account for this assuming page alignment at worst. */
3090 if (use_rvc
3091 && ELFNN_R_TYPE (rel->r_info) == R_RISCV_HI20
3092 && VALID_RVC_LUI_IMM (RISCV_CONST_HIGH_PART (symval))
3093 && VALID_RVC_LUI_IMM (RISCV_CONST_HIGH_PART (symval + ELF_MAXPAGESIZE)))
3094 {
3095 /* Replace LUI with C.LUI if legal (i.e., rd != x0 and rd != x2/sp). */
3096 bfd_vma lui = bfd_get_32 (abfd, contents + rel->r_offset);
3097 unsigned rd = ((unsigned)lui >> OP_SH_RD) & OP_MASK_RD;
3098 if (rd == 0 || rd == X_SP)
3099 return TRUE;
3100
3101 lui = (lui & (OP_MASK_RD << OP_SH_RD)) | MATCH_C_LUI;
3102 bfd_put_32 (abfd, lui, contents + rel->r_offset);
3103
3104 /* Replace the R_RISCV_HI20 reloc. */
3105 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), R_RISCV_RVC_LUI);
3106
3107 *again = TRUE;
3108 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset + 2, 2,
3109 link_info);
3110 }
3111
3112 return TRUE;
3113 }
3114
3115 /* Relax non-PIC TLS references. */
3116
3117 static bfd_boolean
3118 _bfd_riscv_relax_tls_le (bfd *abfd,
3119 asection *sec,
3120 asection *sym_sec ATTRIBUTE_UNUSED,
3121 struct bfd_link_info *link_info,
3122 Elf_Internal_Rela *rel,
3123 bfd_vma symval,
3124 bfd_vma max_alignment ATTRIBUTE_UNUSED,
3125 bfd_vma reserve_size ATTRIBUTE_UNUSED,
3126 bfd_boolean *again,
3127 riscv_pcgp_relocs *prcel_relocs ATTRIBUTE_UNUSED)
3128 {
3129 /* See if this symbol is in range of tp. */
3130 if (RISCV_CONST_HIGH_PART (tpoff (link_info, symval)) != 0)
3131 return TRUE;
3132
3133 BFD_ASSERT (rel->r_offset + 4 <= sec->size);
3134 switch (ELFNN_R_TYPE (rel->r_info))
3135 {
3136 case R_RISCV_TPREL_LO12_I:
3137 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), R_RISCV_TPREL_I);
3138 return TRUE;
3139
3140 case R_RISCV_TPREL_LO12_S:
3141 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), R_RISCV_TPREL_S);
3142 return TRUE;
3143
3144 case R_RISCV_TPREL_HI20:
3145 case R_RISCV_TPREL_ADD:
3146 /* We can delete the unnecessary instruction and reloc. */
3147 rel->r_info = ELFNN_R_INFO (0, R_RISCV_NONE);
3148 *again = TRUE;
3149 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset, 4, link_info);
3150
3151 default:
3152 abort ();
3153 }
3154 }
3155
3156 /* Implement R_RISCV_ALIGN by deleting excess alignment NOPs. */
3157
3158 static bfd_boolean
3159 _bfd_riscv_relax_align (bfd *abfd, asection *sec,
3160 asection *sym_sec,
3161 struct bfd_link_info *link_info,
3162 Elf_Internal_Rela *rel,
3163 bfd_vma symval,
3164 bfd_vma max_alignment ATTRIBUTE_UNUSED,
3165 bfd_vma reserve_size ATTRIBUTE_UNUSED,
3166 bfd_boolean *again ATTRIBUTE_UNUSED,
3167 riscv_pcgp_relocs *pcrel_relocs ATTRIBUTE_UNUSED)
3168 {
3169 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
3170 bfd_vma alignment = 1, pos;
3171 while (alignment <= rel->r_addend)
3172 alignment *= 2;
3173
3174 symval -= rel->r_addend;
3175 bfd_vma aligned_addr = ((symval - 1) & ~(alignment - 1)) + alignment;
3176 bfd_vma nop_bytes = aligned_addr - symval;
3177
3178 /* Once we've handled an R_RISCV_ALIGN, we can't relax anything else. */
3179 sec->sec_flg0 = TRUE;
3180
3181 /* Make sure there are enough NOPs to actually achieve the alignment. */
3182 if (rel->r_addend < nop_bytes)
3183 {
3184 _bfd_error_handler
3185 (_("%pB(%pA+%#" PRIx64 "): %" PRId64 " bytes required for alignment "
3186 "to %" PRId64 "-byte boundary, but only %" PRId64 " present"),
3187 abfd, sym_sec, (uint64_t) rel->r_offset,
3188 (int64_t) nop_bytes, (int64_t) alignment, (int64_t) rel->r_addend);
3189 bfd_set_error (bfd_error_bad_value);
3190 return FALSE;
3191 }
3192
3193 /* Delete the reloc. */
3194 rel->r_info = ELFNN_R_INFO (0, R_RISCV_NONE);
3195
3196 /* If the number of NOPs is already correct, there's nothing to do. */
3197 if (nop_bytes == rel->r_addend)
3198 return TRUE;
3199
3200 /* Write as many RISC-V NOPs as we need. */
3201 for (pos = 0; pos < (nop_bytes & -4); pos += 4)
3202 bfd_put_32 (abfd, RISCV_NOP, contents + rel->r_offset + pos);
3203
3204 /* Write a final RVC NOP if need be. */
3205 if (nop_bytes % 4 != 0)
3206 bfd_put_16 (abfd, RVC_NOP, contents + rel->r_offset + pos);
3207
3208 /* Delete the excess bytes. */
3209 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset + nop_bytes,
3210 rel->r_addend - nop_bytes, link_info);
3211 }
3212
3213 /* Relax PC-relative references to GP-relative references. */
3214
3215 static bfd_boolean
3216 _bfd_riscv_relax_pc (bfd *abfd ATTRIBUTE_UNUSED,
3217 asection *sec,
3218 asection *sym_sec,
3219 struct bfd_link_info *link_info,
3220 Elf_Internal_Rela *rel,
3221 bfd_vma symval,
3222 bfd_vma max_alignment,
3223 bfd_vma reserve_size,
3224 bfd_boolean *again ATTRIBUTE_UNUSED,
3225 riscv_pcgp_relocs *pcgp_relocs)
3226 {
3227 bfd_vma gp = riscv_global_pointer_value (link_info);
3228
3229 BFD_ASSERT (rel->r_offset + 4 <= sec->size);
3230
3231 /* Chain the _LO relocs to their cooresponding _HI reloc to compute the
3232 * actual target address. */
3233 riscv_pcgp_hi_reloc hi_reloc;
3234 memset (&hi_reloc, 0, sizeof (hi_reloc));
3235 switch (ELFNN_R_TYPE (rel->r_info))
3236 {
3237 case R_RISCV_PCREL_LO12_I:
3238 case R_RISCV_PCREL_LO12_S:
3239 {
3240 /* If the %lo has an addend, it isn't for the label pointing at the
3241 hi part instruction, but rather for the symbol pointed at by the
3242 hi part instruction. So we must subtract it here for the lookup.
3243 It is still used below in the final symbol address. */
3244 bfd_vma hi_sec_off = symval - sec_addr (sym_sec) - rel->r_addend;
3245 riscv_pcgp_hi_reloc *hi = riscv_find_pcgp_hi_reloc (pcgp_relocs,
3246 hi_sec_off);
3247 if (hi == NULL)
3248 {
3249 riscv_record_pcgp_lo_reloc (pcgp_relocs, hi_sec_off);
3250 return TRUE;
3251 }
3252
3253 hi_reloc = *hi;
3254 symval = hi_reloc.hi_addr;
3255 sym_sec = hi_reloc.sym_sec;
3256 }
3257 break;
3258
3259 case R_RISCV_PCREL_HI20:
3260 /* Mergeable symbols and code might later move out of range. */
3261 if (sym_sec->flags & (SEC_MERGE | SEC_CODE))
3262 return TRUE;
3263
3264 /* If the cooresponding lo relocation has already been seen then it's not
3265 * safe to relax this relocation. */
3266 if (riscv_find_pcgp_lo_reloc (pcgp_relocs, rel->r_offset))
3267 return TRUE;
3268
3269 break;
3270
3271 default:
3272 abort ();
3273 }
3274
3275 if (gp)
3276 {
3277 /* If gp and the symbol are in the same output section, then
3278 consider only that section's alignment. */
3279 struct bfd_link_hash_entry *h =
3280 bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, FALSE, FALSE, TRUE);
3281 if (h->u.def.section->output_section == sym_sec->output_section)
3282 max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
3283 }
3284
3285 /* Is the reference in range of x0 or gp?
3286 Valid gp range conservatively because of alignment issue. */
3287 if (VALID_ITYPE_IMM (symval)
3288 || (symval >= gp
3289 && VALID_ITYPE_IMM (symval - gp + max_alignment + reserve_size))
3290 || (symval < gp
3291 && VALID_ITYPE_IMM (symval - gp - max_alignment - reserve_size)))
3292 {
3293 unsigned sym = hi_reloc.hi_sym;
3294 switch (ELFNN_R_TYPE (rel->r_info))
3295 {
3296 case R_RISCV_PCREL_LO12_I:
3297 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_I);
3298 rel->r_addend += hi_reloc.hi_addend;
3299 return TRUE;
3300
3301 case R_RISCV_PCREL_LO12_S:
3302 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_S);
3303 rel->r_addend += hi_reloc.hi_addend;
3304 return TRUE;
3305
3306 case R_RISCV_PCREL_HI20:
3307 riscv_record_pcgp_hi_reloc (pcgp_relocs,
3308 rel->r_offset,
3309 rel->r_addend,
3310 symval,
3311 ELFNN_R_SYM(rel->r_info),
3312 sym_sec);
3313 /* We can delete the unnecessary AUIPC and reloc. */
3314 rel->r_info = ELFNN_R_INFO (0, R_RISCV_DELETE);
3315 rel->r_addend = 4;
3316 return TRUE;
3317
3318 default:
3319 abort ();
3320 }
3321 }
3322
3323 return TRUE;
3324 }
3325
3326 /* Relax PC-relative references to GP-relative references. */
3327
3328 static bfd_boolean
3329 _bfd_riscv_relax_delete (bfd *abfd,
3330 asection *sec,
3331 asection *sym_sec ATTRIBUTE_UNUSED,
3332 struct bfd_link_info *link_info,
3333 Elf_Internal_Rela *rel,
3334 bfd_vma symval ATTRIBUTE_UNUSED,
3335 bfd_vma max_alignment ATTRIBUTE_UNUSED,
3336 bfd_vma reserve_size ATTRIBUTE_UNUSED,
3337 bfd_boolean *again ATTRIBUTE_UNUSED,
3338 riscv_pcgp_relocs *pcgp_relocs ATTRIBUTE_UNUSED)
3339 {
3340 if (!riscv_relax_delete_bytes(abfd, sec, rel->r_offset, rel->r_addend,
3341 link_info))
3342 return FALSE;
3343 rel->r_info = ELFNN_R_INFO(0, R_RISCV_NONE);
3344 return TRUE;
3345 }
3346
3347 /* Relax a section. Pass 0 shortens code sequences unless disabled. Pass 1
3348 deletes the bytes that pass 0 made obselete. Pass 2, which cannot be
3349 disabled, handles code alignment directives. */
3350
3351 static bfd_boolean
3352 _bfd_riscv_relax_section (bfd *abfd, asection *sec,
3353 struct bfd_link_info *info,
3354 bfd_boolean *again)
3355 {
3356 Elf_Internal_Shdr *symtab_hdr = &elf_symtab_hdr (abfd);
3357 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info);
3358 struct bfd_elf_section_data *data = elf_section_data (sec);
3359 Elf_Internal_Rela *relocs;
3360 bfd_boolean ret = FALSE;
3361 unsigned int i;
3362 bfd_vma max_alignment, reserve_size = 0;
3363 riscv_pcgp_relocs pcgp_relocs;
3364
3365 *again = FALSE;
3366
3367 if (bfd_link_relocatable (info)
3368 || sec->sec_flg0
3369 || (sec->flags & SEC_RELOC) == 0
3370 || sec->reloc_count == 0
3371 || (info->disable_target_specific_optimizations
3372 && info->relax_pass == 0))
3373 return TRUE;
3374
3375 riscv_init_pcgp_relocs (&pcgp_relocs);
3376
3377 /* Read this BFD's relocs if we haven't done so already. */
3378 if (data->relocs)
3379 relocs = data->relocs;
3380 else if (!(relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
3381 info->keep_memory)))
3382 goto fail;
3383
3384 if (htab)
3385 {
3386 max_alignment = htab->max_alignment;
3387 if (max_alignment == (bfd_vma) -1)
3388 {
3389 max_alignment = _bfd_riscv_get_max_alignment (sec);
3390 htab->max_alignment = max_alignment;
3391 }
3392 }
3393 else
3394 max_alignment = _bfd_riscv_get_max_alignment (sec);
3395
3396 /* Examine and consider relaxing each reloc. */
3397 for (i = 0; i < sec->reloc_count; i++)
3398 {
3399 asection *sym_sec;
3400 Elf_Internal_Rela *rel = relocs + i;
3401 relax_func_t relax_func;
3402 int type = ELFNN_R_TYPE (rel->r_info);
3403 bfd_vma symval;
3404
3405 relax_func = NULL;
3406 if (info->relax_pass == 0)
3407 {
3408 if (type == R_RISCV_CALL || type == R_RISCV_CALL_PLT)
3409 relax_func = _bfd_riscv_relax_call;
3410 else if (type == R_RISCV_HI20
3411 || type == R_RISCV_LO12_I
3412 || type == R_RISCV_LO12_S)
3413 relax_func = _bfd_riscv_relax_lui;
3414 else if (!bfd_link_pic(info)
3415 && (type == R_RISCV_PCREL_HI20
3416 || type == R_RISCV_PCREL_LO12_I
3417 || type == R_RISCV_PCREL_LO12_S))
3418 relax_func = _bfd_riscv_relax_pc;
3419 else if (type == R_RISCV_TPREL_HI20
3420 || type == R_RISCV_TPREL_ADD
3421 || type == R_RISCV_TPREL_LO12_I
3422 || type == R_RISCV_TPREL_LO12_S)
3423 relax_func = _bfd_riscv_relax_tls_le;
3424 else
3425 continue;
3426
3427 /* Only relax this reloc if it is paired with R_RISCV_RELAX. */
3428 if (i == sec->reloc_count - 1
3429 || ELFNN_R_TYPE ((rel + 1)->r_info) != R_RISCV_RELAX
3430 || rel->r_offset != (rel + 1)->r_offset)
3431 continue;
3432
3433 /* Skip over the R_RISCV_RELAX. */
3434 i++;
3435 }
3436 else if (info->relax_pass == 1 && type == R_RISCV_DELETE)
3437 relax_func = _bfd_riscv_relax_delete;
3438 else if (info->relax_pass == 2 && type == R_RISCV_ALIGN)
3439 relax_func = _bfd_riscv_relax_align;
3440 else
3441 continue;
3442
3443 data->relocs = relocs;
3444
3445 /* Read this BFD's contents if we haven't done so already. */
3446 if (!data->this_hdr.contents
3447 && !bfd_malloc_and_get_section (abfd, sec, &data->this_hdr.contents))
3448 goto fail;
3449
3450 /* Read this BFD's symbols if we haven't done so already. */
3451 if (symtab_hdr->sh_info != 0
3452 && !symtab_hdr->contents
3453 && !(symtab_hdr->contents =
3454 (unsigned char *) bfd_elf_get_elf_syms (abfd, symtab_hdr,
3455 symtab_hdr->sh_info,
3456 0, NULL, NULL, NULL)))
3457 goto fail;
3458
3459 /* Get the value of the symbol referred to by the reloc. */
3460 if (ELFNN_R_SYM (rel->r_info) < symtab_hdr->sh_info)
3461 {
3462 /* A local symbol. */
3463 Elf_Internal_Sym *isym = ((Elf_Internal_Sym *) symtab_hdr->contents
3464 + ELFNN_R_SYM (rel->r_info));
3465 reserve_size = (isym->st_size - rel->r_addend) > isym->st_size
3466 ? 0 : isym->st_size - rel->r_addend;
3467
3468 if (isym->st_shndx == SHN_UNDEF)
3469 sym_sec = sec, symval = sec_addr (sec) + rel->r_offset;
3470 else
3471 {
3472 BFD_ASSERT (isym->st_shndx < elf_numsections (abfd));
3473 sym_sec = elf_elfsections (abfd)[isym->st_shndx]->bfd_section;
3474 #if 0
3475 /* The purpose of this code is unknown. It breaks linker scripts
3476 for embedded development that place sections at address zero.
3477 This code is believed to be unnecessary. Disabling it but not
3478 yet removing it, in case something breaks. */
3479 if (sec_addr (sym_sec) == 0)
3480 continue;
3481 #endif
3482 symval = sec_addr (sym_sec) + isym->st_value;
3483 }
3484 }
3485 else
3486 {
3487 unsigned long indx;
3488 struct elf_link_hash_entry *h;
3489
3490 indx = ELFNN_R_SYM (rel->r_info) - symtab_hdr->sh_info;
3491 h = elf_sym_hashes (abfd)[indx];
3492
3493 while (h->root.type == bfd_link_hash_indirect
3494 || h->root.type == bfd_link_hash_warning)
3495 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3496
3497 if (h->plt.offset != MINUS_ONE)
3498 symval = sec_addr (htab->elf.splt) + h->plt.offset;
3499 else if (h->root.u.def.section->output_section == NULL
3500 || (h->root.type != bfd_link_hash_defined
3501 && h->root.type != bfd_link_hash_defweak))
3502 continue;
3503 else
3504 symval = sec_addr (h->root.u.def.section) + h->root.u.def.value;
3505
3506 if (h->type != STT_FUNC)
3507 reserve_size =
3508 (h->size - rel->r_addend) > h->size ? 0 : h->size - rel->r_addend;
3509 sym_sec = h->root.u.def.section;
3510 }
3511
3512 symval += rel->r_addend;
3513
3514 if (!relax_func (abfd, sec, sym_sec, info, rel, symval,
3515 max_alignment, reserve_size, again,
3516 &pcgp_relocs))
3517 goto fail;
3518 }
3519
3520 ret = TRUE;
3521
3522 fail:
3523 if (relocs != data->relocs)
3524 free (relocs);
3525 riscv_free_pcgp_relocs(&pcgp_relocs, abfd, sec);
3526
3527 return ret;
3528 }
3529
3530 #if ARCH_SIZE == 32
3531 # define PRSTATUS_SIZE 0 /* FIXME */
3532 # define PRSTATUS_OFFSET_PR_CURSIG 12
3533 # define PRSTATUS_OFFSET_PR_PID 24
3534 # define PRSTATUS_OFFSET_PR_REG 72
3535 # define ELF_GREGSET_T_SIZE 128
3536 # define PRPSINFO_SIZE 128
3537 # define PRPSINFO_OFFSET_PR_PID 16
3538 # define PRPSINFO_OFFSET_PR_FNAME 32
3539 # define PRPSINFO_OFFSET_PR_PSARGS 48
3540 #else
3541 # define PRSTATUS_SIZE 376
3542 # define PRSTATUS_OFFSET_PR_CURSIG 12
3543 # define PRSTATUS_OFFSET_PR_PID 32
3544 # define PRSTATUS_OFFSET_PR_REG 112
3545 # define ELF_GREGSET_T_SIZE 256
3546 # define PRPSINFO_SIZE 136
3547 # define PRPSINFO_OFFSET_PR_PID 24
3548 # define PRPSINFO_OFFSET_PR_FNAME 40
3549 # define PRPSINFO_OFFSET_PR_PSARGS 56
3550 #endif
3551
3552 /* Support for core dump NOTE sections. */
3553
3554 static bfd_boolean
3555 riscv_elf_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
3556 {
3557 switch (note->descsz)
3558 {
3559 default:
3560 return FALSE;
3561
3562 case PRSTATUS_SIZE: /* sizeof(struct elf_prstatus) on Linux/RISC-V. */
3563 /* pr_cursig */
3564 elf_tdata (abfd)->core->signal
3565 = bfd_get_16 (abfd, note->descdata + PRSTATUS_OFFSET_PR_CURSIG);
3566
3567 /* pr_pid */
3568 elf_tdata (abfd)->core->lwpid
3569 = bfd_get_32 (abfd, note->descdata + PRSTATUS_OFFSET_PR_PID);
3570 break;
3571 }
3572
3573 /* Make a ".reg/999" section. */
3574 return _bfd_elfcore_make_pseudosection (abfd, ".reg", ELF_GREGSET_T_SIZE,
3575 note->descpos + PRSTATUS_OFFSET_PR_REG);
3576 }
3577
3578 static bfd_boolean
3579 riscv_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
3580 {
3581 switch (note->descsz)
3582 {
3583 default:
3584 return FALSE;
3585
3586 case PRPSINFO_SIZE: /* sizeof(struct elf_prpsinfo) on Linux/RISC-V. */
3587 /* pr_pid */
3588 elf_tdata (abfd)->core->pid
3589 = bfd_get_32 (abfd, note->descdata + PRPSINFO_OFFSET_PR_PID);
3590
3591 /* pr_fname */
3592 elf_tdata (abfd)->core->program = _bfd_elfcore_strndup
3593 (abfd, note->descdata + PRPSINFO_OFFSET_PR_FNAME, 16);
3594
3595 /* pr_psargs */
3596 elf_tdata (abfd)->core->command = _bfd_elfcore_strndup
3597 (abfd, note->descdata + PRPSINFO_OFFSET_PR_PSARGS, 80);
3598 break;
3599 }
3600
3601 /* Note that for some reason, a spurious space is tacked
3602 onto the end of the args in some (at least one anyway)
3603 implementations, so strip it off if it exists. */
3604
3605 {
3606 char *command = elf_tdata (abfd)->core->command;
3607 int n = strlen (command);
3608
3609 if (0 < n && command[n - 1] == ' ')
3610 command[n - 1] = '\0';
3611 }
3612
3613 return TRUE;
3614 }
3615
3616 /* Set the right mach type. */
3617 static bfd_boolean
3618 riscv_elf_object_p (bfd *abfd)
3619 {
3620 /* There are only two mach types in RISCV currently. */
3621 if (strcmp (abfd->xvec->name, "elf32-littleriscv") == 0)
3622 bfd_default_set_arch_mach (abfd, bfd_arch_riscv, bfd_mach_riscv32);
3623 else
3624 bfd_default_set_arch_mach (abfd, bfd_arch_riscv, bfd_mach_riscv64);
3625
3626 return TRUE;
3627 }
3628
3629
3630 #define TARGET_LITTLE_SYM riscv_elfNN_vec
3631 #define TARGET_LITTLE_NAME "elfNN-littleriscv"
3632
3633 #define elf_backend_reloc_type_class riscv_reloc_type_class
3634
3635 #define bfd_elfNN_bfd_reloc_name_lookup riscv_reloc_name_lookup
3636 #define bfd_elfNN_bfd_link_hash_table_create riscv_elf_link_hash_table_create
3637 #define bfd_elfNN_bfd_reloc_type_lookup riscv_reloc_type_lookup
3638 #define bfd_elfNN_bfd_merge_private_bfd_data \
3639 _bfd_riscv_elf_merge_private_bfd_data
3640
3641 #define elf_backend_copy_indirect_symbol riscv_elf_copy_indirect_symbol
3642 #define elf_backend_create_dynamic_sections riscv_elf_create_dynamic_sections
3643 #define elf_backend_check_relocs riscv_elf_check_relocs
3644 #define elf_backend_adjust_dynamic_symbol riscv_elf_adjust_dynamic_symbol
3645 #define elf_backend_size_dynamic_sections riscv_elf_size_dynamic_sections
3646 #define elf_backend_relocate_section riscv_elf_relocate_section
3647 #define elf_backend_finish_dynamic_symbol riscv_elf_finish_dynamic_symbol
3648 #define elf_backend_finish_dynamic_sections riscv_elf_finish_dynamic_sections
3649 #define elf_backend_gc_mark_hook riscv_elf_gc_mark_hook
3650 #define elf_backend_plt_sym_val riscv_elf_plt_sym_val
3651 #define elf_backend_grok_prstatus riscv_elf_grok_prstatus
3652 #define elf_backend_grok_psinfo riscv_elf_grok_psinfo
3653 #define elf_backend_object_p riscv_elf_object_p
3654 #define elf_info_to_howto_rel NULL
3655 #define elf_info_to_howto riscv_info_to_howto_rela
3656 #define bfd_elfNN_bfd_relax_section _bfd_riscv_relax_section
3657
3658 #define elf_backend_init_index_section _bfd_elf_init_1_index_section
3659
3660 #define elf_backend_can_gc_sections 1
3661 #define elf_backend_can_refcount 1
3662 #define elf_backend_want_got_plt 1
3663 #define elf_backend_plt_readonly 1
3664 #define elf_backend_plt_alignment 4
3665 #define elf_backend_want_plt_sym 1
3666 #define elf_backend_got_header_size (ARCH_SIZE / 8)
3667 #define elf_backend_want_dynrelro 1
3668 #define elf_backend_rela_normal 1
3669 #define elf_backend_default_execstack 0
3670
3671 #include "elfNN-target.h"
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