1 /* RISC-V-specific support for NN-bit ELF. 2 Copyright (C) 2011-2022 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 #include "objalloc.h" 35 36 #include <limits.h> 37 #ifndef CHAR_BIT 38 #define CHAR_BIT 8 39 #endif 40 41 /* Internal relocations used exclusively by the relaxation pass. */ 42 #define R_RISCV_DELETE (R_RISCV_max + 1) 43 44 #define ARCH_SIZE NN 45 46 #define MINUS_ONE ((bfd_vma)0 - 1) 47 48 #define RISCV_ELF_LOG_WORD_BYTES (ARCH_SIZE == 32 ? 2 : 3) 49 50 #define RISCV_ELF_WORD_BYTES (1 << RISCV_ELF_LOG_WORD_BYTES) 51 52 /* The name of the dynamic interpreter. This is put in the .interp 53 section. */ 54 55 #define ELF64_DYNAMIC_INTERPRETER "/lib/ld.so.1" 56 #define ELF32_DYNAMIC_INTERPRETER "/lib32/ld.so.1" 57 58 #define ELF_ARCH bfd_arch_riscv 59 #define ELF_TARGET_ID RISCV_ELF_DATA 60 #define ELF_MACHINE_CODE EM_RISCV 61 #define ELF_MAXPAGESIZE 0x1000 62 #define ELF_COMMONPAGESIZE 0x1000 63 64 #define RISCV_ATTRIBUTES_SECTION_NAME ".riscv.attributes" 65 66 /* RISC-V ELF linker hash entry. */ 67 68 struct riscv_elf_link_hash_entry 69 { 70 struct elf_link_hash_entry elf; 71 72 #define GOT_UNKNOWN 0 73 #define GOT_NORMAL 1 74 #define GOT_TLS_GD 2 75 #define GOT_TLS_IE 4 76 #define GOT_TLS_LE 8 77 char tls_type; 78 }; 79 80 #define riscv_elf_hash_entry(ent) \ 81 ((struct riscv_elf_link_hash_entry *) (ent)) 82 83 struct _bfd_riscv_elf_obj_tdata 84 { 85 struct elf_obj_tdata root; 86 87 /* tls_type for each local got entry. */ 88 char *local_got_tls_type; 89 }; 90 91 #define _bfd_riscv_elf_tdata(abfd) \ 92 ((struct _bfd_riscv_elf_obj_tdata *) (abfd)->tdata.any) 93 94 #define _bfd_riscv_elf_local_got_tls_type(abfd) \ 95 (_bfd_riscv_elf_tdata (abfd)->local_got_tls_type) 96 97 #define _bfd_riscv_elf_tls_type(abfd, h, symndx) \ 98 (*((h) != NULL ? &riscv_elf_hash_entry (h)->tls_type \ 99 : &_bfd_riscv_elf_local_got_tls_type (abfd) [symndx])) 100 101 #define is_riscv_elf(bfd) \ 102 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ 103 && elf_tdata (bfd) != NULL \ 104 && elf_object_id (bfd) == RISCV_ELF_DATA) 105 106 static bool 107 elfNN_riscv_mkobject (bfd *abfd) 108 { 109 return bfd_elf_allocate_object (abfd, 110 sizeof (struct _bfd_riscv_elf_obj_tdata), 111 RISCV_ELF_DATA); 112 } 113 114 #include "elf/common.h" 115 #include "elf/internal.h" 116 117 struct riscv_elf_link_hash_table 118 { 119 struct elf_link_hash_table elf; 120 121 /* Short-cuts to get to dynamic linker sections. */ 122 asection *sdyntdata; 123 124 /* The max alignment of output sections. */ 125 bfd_vma max_alignment; 126 127 /* Used by local STT_GNU_IFUNC symbols. */ 128 htab_t loc_hash_table; 129 void * loc_hash_memory; 130 131 /* The index of the last unused .rel.iplt slot. */ 132 bfd_vma last_iplt_index; 133 134 /* The data segment phase, don't relax the section 135 when it is exp_seg_relro_adjust. */ 136 int *data_segment_phase; 137 138 /* Relocations for variant CC symbols may be present. */ 139 int variant_cc; 140 }; 141 142 /* Instruction access functions. */ 143 #define riscv_get_insn(bits, ptr) \ 144 ((bits) == 16 ? bfd_getl16 (ptr) \ 145 : (bits) == 32 ? bfd_getl32 (ptr) \ 146 : (bits) == 64 ? bfd_getl64 (ptr) \ 147 : (abort (), (bfd_vma) - 1)) 148 #define riscv_put_insn(bits, val, ptr) \ 149 ((bits) == 16 ? bfd_putl16 (val, ptr) \ 150 : (bits) == 32 ? bfd_putl32 (val, ptr) \ 151 : (bits) == 64 ? bfd_putl64 (val, ptr) \ 152 : (abort (), (void) 0)) 153 154 /* Get the RISC-V ELF linker hash table from a link_info structure. */ 155 #define riscv_elf_hash_table(p) \ 156 ((is_elf_hash_table ((p)->hash) \ 157 && elf_hash_table_id (elf_hash_table (p)) == RISCV_ELF_DATA) \ 158 ? (struct riscv_elf_link_hash_table *) (p)->hash : NULL) 159 160 static bool 161 riscv_info_to_howto_rela (bfd *abfd, 162 arelent *cache_ptr, 163 Elf_Internal_Rela *dst) 164 { 165 cache_ptr->howto = riscv_elf_rtype_to_howto (abfd, ELFNN_R_TYPE (dst->r_info)); 166 return cache_ptr->howto != NULL; 167 } 168 169 static void 170 riscv_elf_append_rela (bfd *abfd, asection *s, Elf_Internal_Rela *rel) 171 { 172 const struct elf_backend_data *bed; 173 bfd_byte *loc; 174 175 bed = get_elf_backend_data (abfd); 176 loc = s->contents + (s->reloc_count++ * bed->s->sizeof_rela); 177 bed->s->swap_reloca_out (abfd, rel, loc); 178 } 179 180 /* Return true if a relocation is modifying an instruction. */ 181 182 static bool 183 riscv_is_insn_reloc (const reloc_howto_type *howto) 184 { 185 /* Heuristic: A multibyte destination with a nontrivial mask 186 is an instruction */ 187 return (howto->bitsize > 8 188 && howto->dst_mask != 0 189 && ~(howto->dst_mask | (howto->bitsize < sizeof(bfd_vma) * CHAR_BIT 190 ? (MINUS_ONE << howto->bitsize) : (bfd_vma)0)) != 0); 191 } 192 193 /* PLT/GOT stuff. */ 194 #define PLT_HEADER_INSNS 8 195 #define PLT_ENTRY_INSNS 4 196 #define PLT_HEADER_SIZE (PLT_HEADER_INSNS * 4) 197 #define PLT_ENTRY_SIZE (PLT_ENTRY_INSNS * 4) 198 #define GOT_ENTRY_SIZE RISCV_ELF_WORD_BYTES 199 /* Reserve two entries of GOTPLT for ld.so, one is used for PLT resolver, 200 the other is used for link map. Other targets also reserve one more 201 entry used for runtime profile? */ 202 #define GOTPLT_HEADER_SIZE (2 * GOT_ENTRY_SIZE) 203 204 #define sec_addr(sec) ((sec)->output_section->vma + (sec)->output_offset) 205 206 #if ARCH_SIZE == 32 207 # define MATCH_LREG MATCH_LW 208 #else 209 # define MATCH_LREG MATCH_LD 210 #endif 211 212 /* Generate a PLT header. */ 213 214 static bool 215 riscv_make_plt_header (bfd *output_bfd, bfd_vma gotplt_addr, bfd_vma addr, 216 uint32_t *entry) 217 { 218 bfd_vma gotplt_offset_high = RISCV_PCREL_HIGH_PART (gotplt_addr, addr); 219 bfd_vma gotplt_offset_low = RISCV_PCREL_LOW_PART (gotplt_addr, addr); 220 221 /* RVE has no t3 register, so this won't work, and is not supported. */ 222 if (elf_elfheader (output_bfd)->e_flags & EF_RISCV_RVE) 223 { 224 _bfd_error_handler (_("%pB: warning: RVE PLT generation not supported"), 225 output_bfd); 226 return false; 227 } 228 229 /* auipc t2, %hi(.got.plt) 230 sub t1, t1, t3 # shifted .got.plt offset + hdr size + 12 231 l[w|d] t3, %lo(.got.plt)(t2) # _dl_runtime_resolve 232 addi t1, t1, -(hdr size + 12) # shifted .got.plt offset 233 addi t0, t2, %lo(.got.plt) # &.got.plt 234 srli t1, t1, log2(16/PTRSIZE) # .got.plt offset 235 l[w|d] t0, PTRSIZE(t0) # link map 236 jr t3 */ 237 238 entry[0] = RISCV_UTYPE (AUIPC, X_T2, gotplt_offset_high); 239 entry[1] = RISCV_RTYPE (SUB, X_T1, X_T1, X_T3); 240 entry[2] = RISCV_ITYPE (LREG, X_T3, X_T2, gotplt_offset_low); 241 entry[3] = RISCV_ITYPE (ADDI, X_T1, X_T1, (uint32_t) -(PLT_HEADER_SIZE + 12)); 242 entry[4] = RISCV_ITYPE (ADDI, X_T0, X_T2, gotplt_offset_low); 243 entry[5] = RISCV_ITYPE (SRLI, X_T1, X_T1, 4 - RISCV_ELF_LOG_WORD_BYTES); 244 entry[6] = RISCV_ITYPE (LREG, X_T0, X_T0, RISCV_ELF_WORD_BYTES); 245 entry[7] = RISCV_ITYPE (JALR, 0, X_T3, 0); 246 247 return true; 248 } 249 250 /* Generate a PLT entry. */ 251 252 static bool 253 riscv_make_plt_entry (bfd *output_bfd, bfd_vma got, bfd_vma addr, 254 uint32_t *entry) 255 { 256 /* RVE has no t3 register, so this won't work, and is not supported. */ 257 if (elf_elfheader (output_bfd)->e_flags & EF_RISCV_RVE) 258 { 259 _bfd_error_handler (_("%pB: warning: RVE PLT generation not supported"), 260 output_bfd); 261 return false; 262 } 263 264 /* auipc t3, %hi(.got.plt entry) 265 l[w|d] t3, %lo(.got.plt entry)(t3) 266 jalr t1, t3 267 nop */ 268 269 entry[0] = RISCV_UTYPE (AUIPC, X_T3, RISCV_PCREL_HIGH_PART (got, addr)); 270 entry[1] = RISCV_ITYPE (LREG, X_T3, X_T3, RISCV_PCREL_LOW_PART (got, addr)); 271 entry[2] = RISCV_ITYPE (JALR, X_T1, X_T3, 0); 272 entry[3] = RISCV_NOP; 273 274 return true; 275 } 276 277 /* Create an entry in an RISC-V ELF linker hash table. */ 278 279 static struct bfd_hash_entry * 280 link_hash_newfunc (struct bfd_hash_entry *entry, 281 struct bfd_hash_table *table, const char *string) 282 { 283 /* Allocate the structure if it has not already been allocated by a 284 subclass. */ 285 if (entry == NULL) 286 { 287 entry = 288 bfd_hash_allocate (table, 289 sizeof (struct riscv_elf_link_hash_entry)); 290 if (entry == NULL) 291 return entry; 292 } 293 294 /* Call the allocation method of the superclass. */ 295 entry = _bfd_elf_link_hash_newfunc (entry, table, string); 296 if (entry != NULL) 297 { 298 struct riscv_elf_link_hash_entry *eh; 299 300 eh = (struct riscv_elf_link_hash_entry *) entry; 301 eh->tls_type = GOT_UNKNOWN; 302 } 303 304 return entry; 305 } 306 307 /* Compute a hash of a local hash entry. We use elf_link_hash_entry 308 for local symbol so that we can handle local STT_GNU_IFUNC symbols 309 as global symbol. We reuse indx and dynstr_index for local symbol 310 hash since they aren't used by global symbols in this backend. */ 311 312 static hashval_t 313 riscv_elf_local_htab_hash (const void *ptr) 314 { 315 struct elf_link_hash_entry *h = (struct elf_link_hash_entry *) ptr; 316 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index); 317 } 318 319 /* Compare local hash entries. */ 320 321 static int 322 riscv_elf_local_htab_eq (const void *ptr1, const void *ptr2) 323 { 324 struct elf_link_hash_entry *h1 = (struct elf_link_hash_entry *) ptr1; 325 struct elf_link_hash_entry *h2 = (struct elf_link_hash_entry *) ptr2; 326 327 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index; 328 } 329 330 /* Find and/or create a hash entry for local symbol. */ 331 332 static struct elf_link_hash_entry * 333 riscv_elf_get_local_sym_hash (struct riscv_elf_link_hash_table *htab, 334 bfd *abfd, const Elf_Internal_Rela *rel, 335 bool create) 336 { 337 struct riscv_elf_link_hash_entry eh, *ret; 338 asection *sec = abfd->sections; 339 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id, 340 ELFNN_R_SYM (rel->r_info)); 341 void **slot; 342 343 eh.elf.indx = sec->id; 344 eh.elf.dynstr_index = ELFNN_R_SYM (rel->r_info); 345 slot = htab_find_slot_with_hash (htab->loc_hash_table, &eh, h, 346 create ? INSERT : NO_INSERT); 347 348 if (!slot) 349 return NULL; 350 351 if (*slot) 352 { 353 ret = (struct riscv_elf_link_hash_entry *) *slot; 354 return &ret->elf; 355 } 356 357 ret = (struct riscv_elf_link_hash_entry *) 358 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory, 359 sizeof (struct riscv_elf_link_hash_entry)); 360 if (ret) 361 { 362 memset (ret, 0, sizeof (*ret)); 363 ret->elf.indx = sec->id; 364 ret->elf.dynstr_index = ELFNN_R_SYM (rel->r_info); 365 ret->elf.dynindx = -1; 366 *slot = ret; 367 } 368 return &ret->elf; 369 } 370 371 /* Destroy a RISC-V elf linker hash table. */ 372 373 static void 374 riscv_elf_link_hash_table_free (bfd *obfd) 375 { 376 struct riscv_elf_link_hash_table *ret 377 = (struct riscv_elf_link_hash_table *) obfd->link.hash; 378 379 if (ret->loc_hash_table) 380 htab_delete (ret->loc_hash_table); 381 if (ret->loc_hash_memory) 382 objalloc_free ((struct objalloc *) ret->loc_hash_memory); 383 384 _bfd_elf_link_hash_table_free (obfd); 385 } 386 387 /* Create a RISC-V ELF linker hash table. */ 388 389 static struct bfd_link_hash_table * 390 riscv_elf_link_hash_table_create (bfd *abfd) 391 { 392 struct riscv_elf_link_hash_table *ret; 393 size_t amt = sizeof (struct riscv_elf_link_hash_table); 394 395 ret = (struct riscv_elf_link_hash_table *) bfd_zmalloc (amt); 396 if (ret == NULL) 397 return NULL; 398 399 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc, 400 sizeof (struct riscv_elf_link_hash_entry), 401 RISCV_ELF_DATA)) 402 { 403 free (ret); 404 return NULL; 405 } 406 407 ret->max_alignment = (bfd_vma) -1; 408 409 /* Create hash table for local ifunc. */ 410 ret->loc_hash_table = htab_try_create (1024, 411 riscv_elf_local_htab_hash, 412 riscv_elf_local_htab_eq, 413 NULL); 414 ret->loc_hash_memory = objalloc_create (); 415 if (!ret->loc_hash_table || !ret->loc_hash_memory) 416 { 417 riscv_elf_link_hash_table_free (abfd); 418 return NULL; 419 } 420 ret->elf.root.hash_table_free = riscv_elf_link_hash_table_free; 421 422 return &ret->elf.root; 423 } 424 425 /* Create the .got section. */ 426 427 static bool 428 riscv_elf_create_got_section (bfd *abfd, struct bfd_link_info *info) 429 { 430 flagword flags; 431 asection *s, *s_got; 432 struct elf_link_hash_entry *h; 433 const struct elf_backend_data *bed = get_elf_backend_data (abfd); 434 struct elf_link_hash_table *htab = elf_hash_table (info); 435 436 /* This function may be called more than once. */ 437 if (htab->sgot != NULL) 438 return true; 439 440 flags = bed->dynamic_sec_flags; 441 442 s = bfd_make_section_anyway_with_flags (abfd, 443 (bed->rela_plts_and_copies_p 444 ? ".rela.got" : ".rel.got"), 445 (bed->dynamic_sec_flags 446 | SEC_READONLY)); 447 if (s == NULL 448 || !bfd_set_section_alignment (s, bed->s->log_file_align)) 449 return false; 450 htab->srelgot = s; 451 452 s = s_got = bfd_make_section_anyway_with_flags (abfd, ".got", flags); 453 if (s == NULL 454 || !bfd_set_section_alignment (s, bed->s->log_file_align)) 455 return false; 456 htab->sgot = s; 457 458 /* The first bit of the global offset table is the header. */ 459 s->size += bed->got_header_size; 460 461 if (bed->want_got_plt) 462 { 463 s = bfd_make_section_anyway_with_flags (abfd, ".got.plt", flags); 464 if (s == NULL 465 || !bfd_set_section_alignment (s, bed->s->log_file_align)) 466 return false; 467 htab->sgotplt = s; 468 469 /* Reserve room for the header. */ 470 s->size += GOTPLT_HEADER_SIZE; 471 } 472 473 if (bed->want_got_sym) 474 { 475 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got 476 section. We don't do this in the linker script because we don't want 477 to define the symbol if we are not creating a global offset 478 table. */ 479 h = _bfd_elf_define_linkage_sym (abfd, info, s_got, 480 "_GLOBAL_OFFSET_TABLE_"); 481 elf_hash_table (info)->hgot = h; 482 if (h == NULL) 483 return false; 484 } 485 486 return true; 487 } 488 489 /* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and 490 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our 491 hash table. */ 492 493 static bool 494 riscv_elf_create_dynamic_sections (bfd *dynobj, 495 struct bfd_link_info *info) 496 { 497 struct riscv_elf_link_hash_table *htab; 498 499 htab = riscv_elf_hash_table (info); 500 BFD_ASSERT (htab != NULL); 501 502 if (!riscv_elf_create_got_section (dynobj, info)) 503 return false; 504 505 if (!_bfd_elf_create_dynamic_sections (dynobj, info)) 506 return false; 507 508 if (!bfd_link_pic (info)) 509 { 510 /* Technically, this section doesn't have contents. It is used as the 511 target of TLS copy relocs, to copy TLS data from shared libraries into 512 the executable. However, if we don't mark it as loadable, then it 513 matches the IS_TBSS test in ldlang.c, and there is no run-time address 514 space allocated for it even though it has SEC_ALLOC. That test is 515 correct for .tbss, but not correct for this section. There is also 516 a second problem that having a section with no contents can only work 517 if it comes after all sections with contents in the same segment, 518 but the linker script does not guarantee that. This is just mixed in 519 with other .tdata.* sections. We can fix both problems by lying and 520 saying that there are contents. This section is expected to be small 521 so this should not cause a significant extra program startup cost. */ 522 htab->sdyntdata = 523 bfd_make_section_anyway_with_flags (dynobj, ".tdata.dyn", 524 (SEC_ALLOC | SEC_THREAD_LOCAL 525 | SEC_LOAD | SEC_DATA 526 | SEC_HAS_CONTENTS 527 | SEC_LINKER_CREATED)); 528 } 529 530 if (!htab->elf.splt || !htab->elf.srelplt || !htab->elf.sdynbss 531 || (!bfd_link_pic (info) && (!htab->elf.srelbss || !htab->sdyntdata))) 532 abort (); 533 534 return true; 535 } 536 537 /* Copy the extra info we tack onto an elf_link_hash_entry. */ 538 539 static void 540 riscv_elf_copy_indirect_symbol (struct bfd_link_info *info, 541 struct elf_link_hash_entry *dir, 542 struct elf_link_hash_entry *ind) 543 { 544 struct riscv_elf_link_hash_entry *edir, *eind; 545 546 edir = (struct riscv_elf_link_hash_entry *) dir; 547 eind = (struct riscv_elf_link_hash_entry *) ind; 548 549 if (ind->root.type == bfd_link_hash_indirect 550 && dir->got.refcount <= 0) 551 { 552 edir->tls_type = eind->tls_type; 553 eind->tls_type = GOT_UNKNOWN; 554 } 555 _bfd_elf_link_hash_copy_indirect (info, dir, ind); 556 } 557 558 static bool 559 riscv_elf_record_tls_type (bfd *abfd, struct elf_link_hash_entry *h, 560 unsigned long symndx, char tls_type) 561 { 562 char *new_tls_type = &_bfd_riscv_elf_tls_type (abfd, h, symndx); 563 564 *new_tls_type |= tls_type; 565 if ((*new_tls_type & GOT_NORMAL) && (*new_tls_type & ~GOT_NORMAL)) 566 { 567 (*_bfd_error_handler) 568 (_("%pB: `%s' accessed both as normal and thread local symbol"), 569 abfd, h ? h->root.root.string : "<local>"); 570 return false; 571 } 572 return true; 573 } 574 575 static bool 576 riscv_elf_record_got_reference (bfd *abfd, struct bfd_link_info *info, 577 struct elf_link_hash_entry *h, long symndx) 578 { 579 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info); 580 Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 581 582 if (htab->elf.sgot == NULL) 583 { 584 if (!riscv_elf_create_got_section (htab->elf.dynobj, info)) 585 return false; 586 } 587 588 if (h != NULL) 589 { 590 h->got.refcount += 1; 591 return true; 592 } 593 594 /* This is a global offset table entry for a local symbol. */ 595 if (elf_local_got_refcounts (abfd) == NULL) 596 { 597 bfd_size_type size = symtab_hdr->sh_info * (sizeof (bfd_vma) + 1); 598 if (!(elf_local_got_refcounts (abfd) = bfd_zalloc (abfd, size))) 599 return false; 600 _bfd_riscv_elf_local_got_tls_type (abfd) 601 = (char *) (elf_local_got_refcounts (abfd) + symtab_hdr->sh_info); 602 } 603 elf_local_got_refcounts (abfd) [symndx] += 1; 604 605 return true; 606 } 607 608 static bool 609 bad_static_reloc (bfd *abfd, unsigned r_type, struct elf_link_hash_entry *h) 610 { 611 reloc_howto_type * r = riscv_elf_rtype_to_howto (abfd, r_type); 612 613 /* We propably can improve the information to tell users that they 614 should be recompile the code with -fPIC or -fPIE, just like what 615 x86 does. */ 616 (*_bfd_error_handler) 617 (_("%pB: relocation %s against `%s' can not be used when making a shared " 618 "object; recompile with -fPIC"), 619 abfd, r ? r->name : _("<unknown>"), 620 h != NULL ? h->root.root.string : "a local symbol"); 621 bfd_set_error (bfd_error_bad_value); 622 return false; 623 } 624 625 /* Look through the relocs for a section during the first phase, and 626 allocate space in the global offset table or procedure linkage 627 table. */ 628 629 static bool 630 riscv_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, 631 asection *sec, const Elf_Internal_Rela *relocs) 632 { 633 struct riscv_elf_link_hash_table *htab; 634 Elf_Internal_Shdr *symtab_hdr; 635 struct elf_link_hash_entry **sym_hashes; 636 const Elf_Internal_Rela *rel; 637 asection *sreloc = NULL; 638 639 if (bfd_link_relocatable (info)) 640 return true; 641 642 htab = riscv_elf_hash_table (info); 643 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 644 sym_hashes = elf_sym_hashes (abfd); 645 646 if (htab->elf.dynobj == NULL) 647 htab->elf.dynobj = abfd; 648 649 for (rel = relocs; rel < relocs + sec->reloc_count; rel++) 650 { 651 unsigned int r_type; 652 unsigned int r_symndx; 653 struct elf_link_hash_entry *h; 654 655 r_symndx = ELFNN_R_SYM (rel->r_info); 656 r_type = ELFNN_R_TYPE (rel->r_info); 657 658 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr)) 659 { 660 (*_bfd_error_handler) (_("%pB: bad symbol index: %d"), 661 abfd, r_symndx); 662 return false; 663 } 664 665 if (r_symndx < symtab_hdr->sh_info) 666 { 667 /* A local symbol. */ 668 Elf_Internal_Sym *isym = bfd_sym_from_r_symndx (&htab->elf.sym_cache, 669 abfd, r_symndx); 670 if (isym == NULL) 671 return false; 672 673 /* Check relocation against local STT_GNU_IFUNC symbol. */ 674 if (ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC) 675 { 676 h = riscv_elf_get_local_sym_hash (htab, abfd, rel, true); 677 if (h == NULL) 678 return false; 679 680 /* Fake STT_GNU_IFUNC global symbol. */ 681 h->root.root.string = bfd_elf_sym_name (abfd, symtab_hdr, 682 isym, NULL); 683 h->type = STT_GNU_IFUNC; 684 h->def_regular = 1; 685 h->ref_regular = 1; 686 h->forced_local = 1; 687 h->root.type = bfd_link_hash_defined; 688 } 689 else 690 h = NULL; 691 } 692 else 693 { 694 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 695 while (h->root.type == bfd_link_hash_indirect 696 || h->root.type == bfd_link_hash_warning) 697 h = (struct elf_link_hash_entry *) h->root.u.i.link; 698 } 699 700 if (h != NULL) 701 { 702 switch (r_type) 703 { 704 case R_RISCV_32: 705 case R_RISCV_64: 706 case R_RISCV_CALL: 707 case R_RISCV_CALL_PLT: 708 case R_RISCV_HI20: 709 case R_RISCV_GOT_HI20: 710 case R_RISCV_PCREL_HI20: 711 /* Create the ifunc sections, iplt and ipltgot, for static 712 executables. */ 713 if (h->type == STT_GNU_IFUNC 714 && !_bfd_elf_create_ifunc_sections (htab->elf.dynobj, info)) 715 return false; 716 break; 717 718 default: 719 break; 720 } 721 722 /* It is referenced by a non-shared object. */ 723 h->ref_regular = 1; 724 } 725 726 switch (r_type) 727 { 728 case R_RISCV_TLS_GD_HI20: 729 if (!riscv_elf_record_got_reference (abfd, info, h, r_symndx) 730 || !riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_TLS_GD)) 731 return false; 732 break; 733 734 case R_RISCV_TLS_GOT_HI20: 735 if (bfd_link_pic (info)) 736 info->flags |= DF_STATIC_TLS; 737 if (!riscv_elf_record_got_reference (abfd, info, h, r_symndx) 738 || !riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_TLS_IE)) 739 return false; 740 break; 741 742 case R_RISCV_GOT_HI20: 743 if (!riscv_elf_record_got_reference (abfd, info, h, r_symndx) 744 || !riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_NORMAL)) 745 return false; 746 break; 747 748 case R_RISCV_CALL: 749 case R_RISCV_CALL_PLT: 750 /* These symbol requires a procedure linkage table entry. 751 We actually build the entry in adjust_dynamic_symbol, 752 because these might be a case of linking PIC code without 753 linking in any dynamic objects, in which case we don't 754 need to generate a procedure linkage table after all. */ 755 756 /* If it is a local symbol, then we resolve it directly 757 without creating a PLT entry. */ 758 if (h == NULL) 759 continue; 760 761 h->needs_plt = 1; 762 h->plt.refcount += 1; 763 break; 764 765 case R_RISCV_PCREL_HI20: 766 if (h != NULL 767 && h->type == STT_GNU_IFUNC) 768 { 769 h->non_got_ref = 1; 770 h->pointer_equality_needed = 1; 771 772 /* We don't use the PCREL_HI20 in the data section, 773 so we always need the plt when it refers to 774 ifunc symbol. */ 775 h->plt.refcount += 1; 776 } 777 /* Fall through. */ 778 779 case R_RISCV_JAL: 780 case R_RISCV_BRANCH: 781 case R_RISCV_RVC_BRANCH: 782 case R_RISCV_RVC_JUMP: 783 /* In shared libraries and pie, these relocs are known 784 to bind locally. */ 785 if (bfd_link_pic (info)) 786 break; 787 goto static_reloc; 788 789 case R_RISCV_TPREL_HI20: 790 if (!bfd_link_executable (info)) 791 return bad_static_reloc (abfd, r_type, h); 792 if (h != NULL) 793 riscv_elf_record_tls_type (abfd, h, r_symndx, GOT_TLS_LE); 794 goto static_reloc; 795 796 case R_RISCV_HI20: 797 if (bfd_link_pic (info)) 798 return bad_static_reloc (abfd, r_type, h); 799 /* Fall through. */ 800 801 case R_RISCV_COPY: 802 case R_RISCV_JUMP_SLOT: 803 case R_RISCV_RELATIVE: 804 case R_RISCV_64: 805 case R_RISCV_32: 806 /* Fall through. */ 807 808 static_reloc: 809 810 if (h != NULL 811 && (!bfd_link_pic (info) 812 || h->type == STT_GNU_IFUNC)) 813 { 814 /* This reloc might not bind locally. */ 815 h->non_got_ref = 1; 816 h->pointer_equality_needed = 1; 817 818 if (!h->def_regular 819 || (sec->flags & (SEC_CODE | SEC_READONLY)) != 0) 820 { 821 /* We may need a .plt entry if the symbol is a function 822 defined in a shared lib or is a function referenced 823 from the code or read-only section. */ 824 h->plt.refcount += 1; 825 } 826 } 827 828 /* If we are creating a shared library, and this is a reloc 829 against a global symbol, or a non PC relative reloc 830 against a local symbol, then we need to copy the reloc 831 into the shared library. However, if we are linking with 832 -Bsymbolic, we do not need to copy a reloc against a 833 global symbol which is defined in an object we are 834 including in the link (i.e., DEF_REGULAR is set). At 835 this point we have not seen all the input files, so it is 836 possible that DEF_REGULAR is not set now but will be set 837 later (it is never cleared). In case of a weak definition, 838 DEF_REGULAR may be cleared later by a strong definition in 839 a shared library. We account for that possibility below by 840 storing information in the relocs_copied field of the hash 841 table entry. A similar situation occurs when creating 842 shared libraries and symbol visibility changes render the 843 symbol local. 844 845 If on the other hand, we are creating an executable, we 846 may need to keep relocations for symbols satisfied by a 847 dynamic library if we manage to avoid copy relocs for the 848 symbol. 849 850 Generate dynamic pointer relocation against STT_GNU_IFUNC 851 symbol in the non-code section (R_RISCV_32/R_RISCV_64). */ 852 reloc_howto_type * r = riscv_elf_rtype_to_howto (abfd, r_type); 853 854 if ((bfd_link_pic (info) 855 && (sec->flags & SEC_ALLOC) != 0 856 && ((r != NULL && !r->pc_relative) 857 || (h != NULL 858 && (!info->symbolic 859 || h->root.type == bfd_link_hash_defweak 860 || !h->def_regular)))) 861 || (!bfd_link_pic (info) 862 && (sec->flags & SEC_ALLOC) != 0 863 && h != NULL 864 && (h->root.type == bfd_link_hash_defweak 865 || !h->def_regular)) 866 || (!bfd_link_pic (info) 867 && h != NULL 868 && h->type == STT_GNU_IFUNC 869 && (sec->flags & SEC_CODE) == 0)) 870 { 871 struct elf_dyn_relocs *p; 872 struct elf_dyn_relocs **head; 873 874 /* When creating a shared object, we must copy these 875 relocs into the output file. We create a reloc 876 section in dynobj and make room for the reloc. */ 877 if (sreloc == NULL) 878 { 879 sreloc = _bfd_elf_make_dynamic_reloc_section 880 (sec, htab->elf.dynobj, RISCV_ELF_LOG_WORD_BYTES, 881 abfd, /*rela?*/ true); 882 883 if (sreloc == NULL) 884 return false; 885 } 886 887 /* If this is a global symbol, we count the number of 888 relocations we need for this symbol. */ 889 if (h != NULL) 890 head = &h->dyn_relocs; 891 else 892 { 893 /* Track dynamic relocs needed for local syms too. 894 We really need local syms available to do this 895 easily. Oh well. */ 896 897 asection *s; 898 void *vpp; 899 Elf_Internal_Sym *isym; 900 901 isym = bfd_sym_from_r_symndx (&htab->elf.sym_cache, 902 abfd, r_symndx); 903 if (isym == NULL) 904 return false; 905 906 s = bfd_section_from_elf_index (abfd, isym->st_shndx); 907 if (s == NULL) 908 s = sec; 909 910 vpp = &elf_section_data (s)->local_dynrel; 911 head = (struct elf_dyn_relocs **) vpp; 912 } 913 914 p = *head; 915 if (p == NULL || p->sec != sec) 916 { 917 size_t amt = sizeof *p; 918 p = ((struct elf_dyn_relocs *) 919 bfd_alloc (htab->elf.dynobj, amt)); 920 if (p == NULL) 921 return false; 922 p->next = *head; 923 *head = p; 924 p->sec = sec; 925 p->count = 0; 926 p->pc_count = 0; 927 } 928 929 p->count += 1; 930 p->pc_count += r == NULL ? 0 : r->pc_relative; 931 } 932 933 break; 934 935 default: 936 break; 937 } 938 } 939 940 return true; 941 } 942 943 /* Adjust a symbol defined by a dynamic object and referenced by a 944 regular object. The current definition is in some section of the 945 dynamic object, but we're not including those sections. We have to 946 change the definition to something the rest of the link can 947 understand. */ 948 949 static bool 950 riscv_elf_adjust_dynamic_symbol (struct bfd_link_info *info, 951 struct elf_link_hash_entry *h) 952 { 953 struct riscv_elf_link_hash_table *htab; 954 struct riscv_elf_link_hash_entry * eh; 955 bfd *dynobj; 956 asection *s, *srel; 957 958 htab = riscv_elf_hash_table (info); 959 BFD_ASSERT (htab != NULL); 960 961 dynobj = htab->elf.dynobj; 962 963 /* Make sure we know what is going on here. */ 964 BFD_ASSERT (dynobj != NULL 965 && (h->needs_plt 966 || h->type == STT_GNU_IFUNC 967 || h->is_weakalias 968 || (h->def_dynamic 969 && h->ref_regular 970 && !h->def_regular))); 971 972 /* If this is a function, put it in the procedure linkage table. We 973 will fill in the contents of the procedure linkage table later 974 (although we could actually do it here). */ 975 if (h->type == STT_FUNC || h->type == STT_GNU_IFUNC || h->needs_plt) 976 { 977 if (h->plt.refcount <= 0 978 || (h->type != STT_GNU_IFUNC 979 && (SYMBOL_CALLS_LOCAL (info, h) 980 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT 981 && h->root.type == bfd_link_hash_undefweak)))) 982 { 983 /* This case can occur if we saw a R_RISCV_CALL_PLT reloc in an 984 input file, but the symbol was never referred to by a dynamic 985 object, or if all references were garbage collected. In such 986 a case, we don't actually need to build a PLT entry. */ 987 h->plt.offset = (bfd_vma) -1; 988 h->needs_plt = 0; 989 } 990 991 return true; 992 } 993 else 994 h->plt.offset = (bfd_vma) -1; 995 996 /* If this is a weak symbol, and there is a real definition, the 997 processor independent code will have arranged for us to see the 998 real definition first, and we can just use the same value. */ 999 if (h->is_weakalias) 1000 { 1001 struct elf_link_hash_entry *def = weakdef (h); 1002 BFD_ASSERT (def->root.type == bfd_link_hash_defined); 1003 h->root.u.def.section = def->root.u.def.section; 1004 h->root.u.def.value = def->root.u.def.value; 1005 return true; 1006 } 1007 1008 /* This is a reference to a symbol defined by a dynamic object which 1009 is not a function. */ 1010 1011 /* If we are creating a shared library, we must presume that the 1012 only references to the symbol are via the global offset table. 1013 For such cases we need not do anything here; the relocations will 1014 be handled correctly by relocate_section. */ 1015 if (bfd_link_pic (info)) 1016 return true; 1017 1018 /* If there are no references to this symbol that do not use the 1019 GOT, we don't need to generate a copy reloc. */ 1020 if (!h->non_got_ref) 1021 return true; 1022 1023 /* If -z nocopyreloc was given, we won't generate them either. */ 1024 if (info->nocopyreloc) 1025 { 1026 h->non_got_ref = 0; 1027 return true; 1028 } 1029 1030 /* If we don't find any dynamic relocs in read-only sections, then 1031 we'll be keeping the dynamic relocs and avoiding the copy reloc. */ 1032 if (!_bfd_elf_readonly_dynrelocs (h)) 1033 { 1034 h->non_got_ref = 0; 1035 return true; 1036 } 1037 1038 /* We must allocate the symbol in our .dynbss section, which will 1039 become part of the .bss section of the executable. There will be 1040 an entry for this symbol in the .dynsym section. The dynamic 1041 object will contain position independent code, so all references 1042 from the dynamic object to this symbol will go through the global 1043 offset table. The dynamic linker will use the .dynsym entry to 1044 determine the address it must put in the global offset table, so 1045 both the dynamic object and the regular object will refer to the 1046 same memory location for the variable. */ 1047 1048 /* We must generate a R_RISCV_COPY reloc to tell the dynamic linker 1049 to copy the initial value out of the dynamic object and into the 1050 runtime process image. We need to remember the offset into the 1051 .rel.bss section we are going to use. */ 1052 eh = (struct riscv_elf_link_hash_entry *) h; 1053 if (eh->tls_type & ~GOT_NORMAL) 1054 { 1055 s = htab->sdyntdata; 1056 srel = htab->elf.srelbss; 1057 } 1058 else if ((h->root.u.def.section->flags & SEC_READONLY) != 0) 1059 { 1060 s = htab->elf.sdynrelro; 1061 srel = htab->elf.sreldynrelro; 1062 } 1063 else 1064 { 1065 s = htab->elf.sdynbss; 1066 srel = htab->elf.srelbss; 1067 } 1068 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0) 1069 { 1070 srel->size += sizeof (ElfNN_External_Rela); 1071 h->needs_copy = 1; 1072 } 1073 1074 return _bfd_elf_adjust_dynamic_copy (info, h, s); 1075 } 1076 1077 /* Allocate space in .plt, .got and associated reloc sections for 1078 dynamic relocs. */ 1079 1080 static bool 1081 allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) 1082 { 1083 struct bfd_link_info *info; 1084 struct riscv_elf_link_hash_table *htab; 1085 struct elf_dyn_relocs *p; 1086 1087 if (h->root.type == bfd_link_hash_indirect) 1088 return true; 1089 1090 info = (struct bfd_link_info *) inf; 1091 htab = riscv_elf_hash_table (info); 1092 BFD_ASSERT (htab != NULL); 1093 1094 /* When we are generating pde, make sure gp symbol is output as a 1095 dynamic symbol. Then ld.so can set the gp register earlier, before 1096 resolving the ifunc. */ 1097 if (!bfd_link_pic (info) 1098 && htab->elf.dynamic_sections_created 1099 && strcmp (h->root.root.string, RISCV_GP_SYMBOL) == 0 1100 && !bfd_elf_link_record_dynamic_symbol (info, h)) 1101 return false; 1102 1103 /* Since STT_GNU_IFUNC symbols must go through PLT, we handle them 1104 in the allocate_ifunc_dynrelocs and allocate_local_ifunc_dynrelocs, 1105 if they are defined and referenced in a non-shared object. */ 1106 if (h->type == STT_GNU_IFUNC 1107 && h->def_regular) 1108 return true; 1109 else if (htab->elf.dynamic_sections_created 1110 && h->plt.refcount > 0) 1111 { 1112 /* Make sure this symbol is output as a dynamic symbol. 1113 Undefined weak syms won't yet be marked as dynamic. */ 1114 if (h->dynindx == -1 1115 && !h->forced_local) 1116 { 1117 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1118 return false; 1119 } 1120 1121 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, bfd_link_pic (info), h)) 1122 { 1123 asection *s = htab->elf.splt; 1124 1125 if (s->size == 0) 1126 s->size = PLT_HEADER_SIZE; 1127 1128 h->plt.offset = s->size; 1129 1130 /* Make room for this entry. */ 1131 s->size += PLT_ENTRY_SIZE; 1132 1133 /* We also need to make an entry in the .got.plt section. */ 1134 htab->elf.sgotplt->size += GOT_ENTRY_SIZE; 1135 1136 /* We also need to make an entry in the .rela.plt section. */ 1137 htab->elf.srelplt->size += sizeof (ElfNN_External_Rela); 1138 1139 /* If this symbol is not defined in a regular file, and we are 1140 not generating a shared library, then set the symbol to this 1141 location in the .plt. This is required to make function 1142 pointers compare as equal between the normal executable and 1143 the shared library. */ 1144 if (! bfd_link_pic (info) 1145 && !h->def_regular) 1146 { 1147 h->root.u.def.section = s; 1148 h->root.u.def.value = h->plt.offset; 1149 } 1150 1151 /* If the symbol has STO_RISCV_VARIANT_CC flag, then raise the 1152 variant_cc flag of riscv_elf_link_hash_table. */ 1153 if (h->other & STO_RISCV_VARIANT_CC) 1154 htab->variant_cc = 1; 1155 } 1156 else 1157 { 1158 h->plt.offset = (bfd_vma) -1; 1159 h->needs_plt = 0; 1160 } 1161 } 1162 else 1163 { 1164 h->plt.offset = (bfd_vma) -1; 1165 h->needs_plt = 0; 1166 } 1167 1168 if (h->got.refcount > 0) 1169 { 1170 asection *s; 1171 bool dyn; 1172 int tls_type = riscv_elf_hash_entry (h)->tls_type; 1173 1174 /* Make sure this symbol is output as a dynamic symbol. 1175 Undefined weak syms won't yet be marked as dynamic. */ 1176 if (h->dynindx == -1 1177 && !h->forced_local) 1178 { 1179 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1180 return false; 1181 } 1182 1183 s = htab->elf.sgot; 1184 h->got.offset = s->size; 1185 dyn = htab->elf.dynamic_sections_created; 1186 if (tls_type & (GOT_TLS_GD | GOT_TLS_IE)) 1187 { 1188 /* TLS_GD needs two dynamic relocs and two GOT slots. */ 1189 if (tls_type & GOT_TLS_GD) 1190 { 1191 s->size += 2 * RISCV_ELF_WORD_BYTES; 1192 htab->elf.srelgot->size += 2 * sizeof (ElfNN_External_Rela); 1193 } 1194 1195 /* TLS_IE needs one dynamic reloc and one GOT slot. */ 1196 if (tls_type & GOT_TLS_IE) 1197 { 1198 s->size += RISCV_ELF_WORD_BYTES; 1199 htab->elf.srelgot->size += sizeof (ElfNN_External_Rela); 1200 } 1201 } 1202 else 1203 { 1204 s->size += RISCV_ELF_WORD_BYTES; 1205 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, bfd_link_pic (info), h) 1206 && ! UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)) 1207 htab->elf.srelgot->size += sizeof (ElfNN_External_Rela); 1208 } 1209 } 1210 else 1211 h->got.offset = (bfd_vma) -1; 1212 1213 if (h->dyn_relocs == NULL) 1214 return true; 1215 1216 /* In the shared -Bsymbolic case, discard space allocated for 1217 dynamic pc-relative relocs against symbols which turn out to be 1218 defined in regular objects. For the normal shared case, discard 1219 space for pc-relative relocs that have become local due to symbol 1220 visibility changes. */ 1221 1222 if (bfd_link_pic (info)) 1223 { 1224 if (SYMBOL_CALLS_LOCAL (info, h)) 1225 { 1226 struct elf_dyn_relocs **pp; 1227 1228 for (pp = &h->dyn_relocs; (p = *pp) != NULL; ) 1229 { 1230 p->count -= p->pc_count; 1231 p->pc_count = 0; 1232 if (p->count == 0) 1233 *pp = p->next; 1234 else 1235 pp = &p->next; 1236 } 1237 } 1238 1239 /* Also discard relocs on undefined weak syms with non-default 1240 visibility. */ 1241 if (h->dyn_relocs != NULL 1242 && h->root.type == bfd_link_hash_undefweak) 1243 { 1244 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT 1245 || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)) 1246 h->dyn_relocs = NULL; 1247 1248 /* Make sure undefined weak symbols are output as a dynamic 1249 symbol in PIEs. */ 1250 else if (h->dynindx == -1 1251 && !h->forced_local) 1252 { 1253 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1254 return false; 1255 } 1256 } 1257 } 1258 else 1259 { 1260 /* For the non-shared case, discard space for relocs against 1261 symbols which turn out to need copy relocs or are not 1262 dynamic. */ 1263 1264 if (!h->non_got_ref 1265 && ((h->def_dynamic 1266 && !h->def_regular) 1267 || (htab->elf.dynamic_sections_created 1268 && (h->root.type == bfd_link_hash_undefweak 1269 || h->root.type == bfd_link_hash_undefined)))) 1270 { 1271 /* Make sure this symbol is output as a dynamic symbol. 1272 Undefined weak syms won't yet be marked as dynamic. */ 1273 if (h->dynindx == -1 1274 && !h->forced_local) 1275 { 1276 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1277 return false; 1278 } 1279 1280 /* If that succeeded, we know we'll be keeping all the 1281 relocs. */ 1282 if (h->dynindx != -1) 1283 goto keep; 1284 } 1285 1286 h->dyn_relocs = NULL; 1287 1288 keep: ; 1289 } 1290 1291 /* Finally, allocate space. */ 1292 for (p = h->dyn_relocs; p != NULL; p = p->next) 1293 { 1294 asection *sreloc = elf_section_data (p->sec)->sreloc; 1295 sreloc->size += p->count * sizeof (ElfNN_External_Rela); 1296 } 1297 1298 return true; 1299 } 1300 1301 /* Allocate space in .plt, .got and associated reloc sections for 1302 ifunc dynamic relocs. */ 1303 1304 static bool 1305 allocate_ifunc_dynrelocs (struct elf_link_hash_entry *h, 1306 void *inf) 1307 { 1308 struct bfd_link_info *info; 1309 1310 if (h->root.type == bfd_link_hash_indirect) 1311 return true; 1312 1313 if (h->root.type == bfd_link_hash_warning) 1314 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1315 1316 info = (struct bfd_link_info *) inf; 1317 1318 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it 1319 here if it is defined and referenced in a non-shared object. */ 1320 if (h->type == STT_GNU_IFUNC 1321 && h->def_regular) 1322 return _bfd_elf_allocate_ifunc_dyn_relocs (info, h, 1323 &h->dyn_relocs, 1324 PLT_ENTRY_SIZE, 1325 PLT_HEADER_SIZE, 1326 GOT_ENTRY_SIZE, 1327 true); 1328 return true; 1329 } 1330 1331 /* Allocate space in .plt, .got and associated reloc sections for 1332 local ifunc dynamic relocs. */ 1333 1334 static int 1335 allocate_local_ifunc_dynrelocs (void **slot, void *inf) 1336 { 1337 struct elf_link_hash_entry *h 1338 = (struct elf_link_hash_entry *) *slot; 1339 1340 if (h->type != STT_GNU_IFUNC 1341 || !h->def_regular 1342 || !h->ref_regular 1343 || !h->forced_local 1344 || h->root.type != bfd_link_hash_defined) 1345 abort (); 1346 1347 return allocate_ifunc_dynrelocs (h, inf); 1348 } 1349 1350 static bool 1351 riscv_elf_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) 1352 { 1353 struct riscv_elf_link_hash_table *htab; 1354 bfd *dynobj; 1355 asection *s; 1356 bfd *ibfd; 1357 1358 htab = riscv_elf_hash_table (info); 1359 BFD_ASSERT (htab != NULL); 1360 dynobj = htab->elf.dynobj; 1361 BFD_ASSERT (dynobj != NULL); 1362 1363 if (elf_hash_table (info)->dynamic_sections_created) 1364 { 1365 /* Set the contents of the .interp section to the interpreter. */ 1366 if (bfd_link_executable (info) && !info->nointerp) 1367 { 1368 s = bfd_get_linker_section (dynobj, ".interp"); 1369 BFD_ASSERT (s != NULL); 1370 s->size = strlen (ELFNN_DYNAMIC_INTERPRETER) + 1; 1371 s->contents = (unsigned char *) ELFNN_DYNAMIC_INTERPRETER; 1372 } 1373 } 1374 1375 /* Set up .got offsets for local syms, and space for local dynamic 1376 relocs. */ 1377 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next) 1378 { 1379 bfd_signed_vma *local_got; 1380 bfd_signed_vma *end_local_got; 1381 char *local_tls_type; 1382 bfd_size_type locsymcount; 1383 Elf_Internal_Shdr *symtab_hdr; 1384 asection *srel; 1385 1386 if (! is_riscv_elf (ibfd)) 1387 continue; 1388 1389 for (s = ibfd->sections; s != NULL; s = s->next) 1390 { 1391 struct elf_dyn_relocs *p; 1392 1393 for (p = elf_section_data (s)->local_dynrel; p != NULL; p = p->next) 1394 { 1395 if (!bfd_is_abs_section (p->sec) 1396 && bfd_is_abs_section (p->sec->output_section)) 1397 { 1398 /* Input section has been discarded, either because 1399 it is a copy of a linkonce section or due to 1400 linker script /DISCARD/, so we'll be discarding 1401 the relocs too. */ 1402 } 1403 else if (p->count != 0) 1404 { 1405 srel = elf_section_data (p->sec)->sreloc; 1406 srel->size += p->count * sizeof (ElfNN_External_Rela); 1407 if ((p->sec->output_section->flags & SEC_READONLY) != 0) 1408 info->flags |= DF_TEXTREL; 1409 } 1410 } 1411 } 1412 1413 local_got = elf_local_got_refcounts (ibfd); 1414 if (!local_got) 1415 continue; 1416 1417 symtab_hdr = &elf_symtab_hdr (ibfd); 1418 locsymcount = symtab_hdr->sh_info; 1419 end_local_got = local_got + locsymcount; 1420 local_tls_type = _bfd_riscv_elf_local_got_tls_type (ibfd); 1421 s = htab->elf.sgot; 1422 srel = htab->elf.srelgot; 1423 for (; local_got < end_local_got; ++local_got, ++local_tls_type) 1424 { 1425 if (*local_got > 0) 1426 { 1427 *local_got = s->size; 1428 s->size += RISCV_ELF_WORD_BYTES; 1429 if (*local_tls_type & GOT_TLS_GD) 1430 s->size += RISCV_ELF_WORD_BYTES; 1431 if (bfd_link_pic (info) 1432 || (*local_tls_type & (GOT_TLS_GD | GOT_TLS_IE))) 1433 srel->size += sizeof (ElfNN_External_Rela); 1434 } 1435 else 1436 *local_got = (bfd_vma) -1; 1437 } 1438 } 1439 1440 /* Allocate .plt and .got entries and space dynamic relocs for 1441 global symbols. */ 1442 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, info); 1443 1444 /* Allocate .plt and .got entries and space dynamic relocs for 1445 global ifunc symbols. */ 1446 elf_link_hash_traverse (&htab->elf, allocate_ifunc_dynrelocs, info); 1447 1448 /* Allocate .plt and .got entries and space dynamic relocs for 1449 local ifunc symbols. */ 1450 htab_traverse (htab->loc_hash_table, allocate_local_ifunc_dynrelocs, info); 1451 1452 /* Used to resolve the dynamic relocs overwite problems when 1453 generating static executable. */ 1454 if (htab->elf.irelplt) 1455 htab->last_iplt_index = htab->elf.irelplt->reloc_count - 1; 1456 1457 if (htab->elf.sgotplt) 1458 { 1459 struct elf_link_hash_entry *got; 1460 got = elf_link_hash_lookup (elf_hash_table (info), 1461 "_GLOBAL_OFFSET_TABLE_", 1462 false, false, false); 1463 1464 /* Don't allocate .got.plt section if there are no GOT nor PLT 1465 entries and there is no refeence to _GLOBAL_OFFSET_TABLE_. */ 1466 if ((got == NULL 1467 || !got->ref_regular_nonweak) 1468 && (htab->elf.sgotplt->size == GOTPLT_HEADER_SIZE) 1469 && (htab->elf.splt == NULL 1470 || htab->elf.splt->size == 0) 1471 && (htab->elf.sgot == NULL 1472 || (htab->elf.sgot->size 1473 == get_elf_backend_data (output_bfd)->got_header_size))) 1474 htab->elf.sgotplt->size = 0; 1475 } 1476 1477 /* The check_relocs and adjust_dynamic_symbol entry points have 1478 determined the sizes of the various dynamic sections. Allocate 1479 memory for them. */ 1480 for (s = dynobj->sections; s != NULL; s = s->next) 1481 { 1482 if ((s->flags & SEC_LINKER_CREATED) == 0) 1483 continue; 1484 1485 if (s == htab->elf.splt 1486 || s == htab->elf.sgot 1487 || s == htab->elf.sgotplt 1488 || s == htab->elf.iplt 1489 || s == htab->elf.igotplt 1490 || s == htab->elf.sdynbss 1491 || s == htab->elf.sdynrelro 1492 || s == htab->sdyntdata) 1493 { 1494 /* Strip this section if we don't need it; see the 1495 comment below. */ 1496 } 1497 else if (startswith (s->name, ".rela")) 1498 { 1499 if (s->size != 0) 1500 { 1501 /* We use the reloc_count field as a counter if we need 1502 to copy relocs into the output file. */ 1503 s->reloc_count = 0; 1504 } 1505 } 1506 else 1507 { 1508 /* It's not one of our sections. */ 1509 continue; 1510 } 1511 1512 if (s->size == 0) 1513 { 1514 /* If we don't need this section, strip it from the 1515 output file. This is mostly to handle .rela.bss and 1516 .rela.plt. We must create both sections in 1517 create_dynamic_sections, because they must be created 1518 before the linker maps input sections to output 1519 sections. The linker does that before 1520 adjust_dynamic_symbol is called, and it is that 1521 function which decides whether anything needs to go 1522 into these sections. */ 1523 s->flags |= SEC_EXCLUDE; 1524 continue; 1525 } 1526 1527 if ((s->flags & SEC_HAS_CONTENTS) == 0) 1528 continue; 1529 1530 /* Allocate memory for the section contents. Zero the memory 1531 for the benefit of .rela.plt, which has 4 unused entries 1532 at the beginning, and we don't want garbage. */ 1533 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size); 1534 if (s->contents == NULL) 1535 return false; 1536 } 1537 1538 /* Add dynamic entries. */ 1539 if (elf_hash_table (info)->dynamic_sections_created) 1540 { 1541 if (!_bfd_elf_add_dynamic_tags (output_bfd, info, true)) 1542 return false; 1543 1544 if (htab->variant_cc 1545 && !_bfd_elf_add_dynamic_entry (info, DT_RISCV_VARIANT_CC, 0)) 1546 return false; 1547 } 1548 1549 return true; 1550 } 1551 1552 #define TP_OFFSET 0 1553 #define DTP_OFFSET 0x800 1554 1555 /* Return the relocation value for a TLS dtp-relative reloc. */ 1556 1557 static bfd_vma 1558 dtpoff (struct bfd_link_info *info, bfd_vma address) 1559 { 1560 /* If tls_sec is NULL, we should have signalled an error already. */ 1561 if (elf_hash_table (info)->tls_sec == NULL) 1562 return 0; 1563 return address - elf_hash_table (info)->tls_sec->vma - DTP_OFFSET; 1564 } 1565 1566 /* Return the relocation value for a static TLS tp-relative relocation. */ 1567 1568 static bfd_vma 1569 tpoff (struct bfd_link_info *info, bfd_vma address) 1570 { 1571 /* If tls_sec is NULL, we should have signalled an error already. */ 1572 if (elf_hash_table (info)->tls_sec == NULL) 1573 return 0; 1574 return address - elf_hash_table (info)->tls_sec->vma - TP_OFFSET; 1575 } 1576 1577 /* Return the global pointer's value, or 0 if it is not in use. */ 1578 1579 static bfd_vma 1580 riscv_global_pointer_value (struct bfd_link_info *info) 1581 { 1582 struct bfd_link_hash_entry *h; 1583 1584 h = bfd_link_hash_lookup (info->hash, RISCV_GP_SYMBOL, false, false, true); 1585 if (h == NULL || h->type != bfd_link_hash_defined) 1586 return 0; 1587 1588 return h->u.def.value + sec_addr (h->u.def.section); 1589 } 1590 1591 /* Emplace a static relocation. */ 1592 1593 static bfd_reloc_status_type 1594 perform_relocation (const reloc_howto_type *howto, 1595 const Elf_Internal_Rela *rel, 1596 bfd_vma value, 1597 asection *input_section, 1598 bfd *input_bfd, 1599 bfd_byte *contents) 1600 { 1601 if (howto->pc_relative) 1602 value -= sec_addr (input_section) + rel->r_offset; 1603 value += rel->r_addend; 1604 1605 switch (ELFNN_R_TYPE (rel->r_info)) 1606 { 1607 case R_RISCV_HI20: 1608 case R_RISCV_TPREL_HI20: 1609 case R_RISCV_PCREL_HI20: 1610 case R_RISCV_GOT_HI20: 1611 case R_RISCV_TLS_GOT_HI20: 1612 case R_RISCV_TLS_GD_HI20: 1613 if (ARCH_SIZE > 32 && !VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (value))) 1614 return bfd_reloc_overflow; 1615 value = ENCODE_UTYPE_IMM (RISCV_CONST_HIGH_PART (value)); 1616 break; 1617 1618 case R_RISCV_LO12_I: 1619 case R_RISCV_GPREL_I: 1620 case R_RISCV_TPREL_LO12_I: 1621 case R_RISCV_TPREL_I: 1622 case R_RISCV_PCREL_LO12_I: 1623 value = ENCODE_ITYPE_IMM (value); 1624 break; 1625 1626 case R_RISCV_LO12_S: 1627 case R_RISCV_GPREL_S: 1628 case R_RISCV_TPREL_LO12_S: 1629 case R_RISCV_TPREL_S: 1630 case R_RISCV_PCREL_LO12_S: 1631 value = ENCODE_STYPE_IMM (value); 1632 break; 1633 1634 case R_RISCV_CALL: 1635 case R_RISCV_CALL_PLT: 1636 if (ARCH_SIZE > 32 && !VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (value))) 1637 return bfd_reloc_overflow; 1638 value = ENCODE_UTYPE_IMM (RISCV_CONST_HIGH_PART (value)) 1639 | (ENCODE_ITYPE_IMM (value) << 32); 1640 break; 1641 1642 case R_RISCV_JAL: 1643 if (!VALID_JTYPE_IMM (value)) 1644 return bfd_reloc_overflow; 1645 value = ENCODE_JTYPE_IMM (value); 1646 break; 1647 1648 case R_RISCV_BRANCH: 1649 if (!VALID_BTYPE_IMM (value)) 1650 return bfd_reloc_overflow; 1651 value = ENCODE_BTYPE_IMM (value); 1652 break; 1653 1654 case R_RISCV_RVC_BRANCH: 1655 if (!VALID_CBTYPE_IMM (value)) 1656 return bfd_reloc_overflow; 1657 value = ENCODE_CBTYPE_IMM (value); 1658 break; 1659 1660 case R_RISCV_RVC_JUMP: 1661 if (!VALID_CJTYPE_IMM (value)) 1662 return bfd_reloc_overflow; 1663 value = ENCODE_CJTYPE_IMM (value); 1664 break; 1665 1666 case R_RISCV_RVC_LUI: 1667 if (RISCV_CONST_HIGH_PART (value) == 0) 1668 { 1669 /* Linker relaxation can convert an address equal to or greater than 1670 0x800 to slightly below 0x800. C.LUI does not accept zero as a 1671 valid immediate. We can fix this by converting it to a C.LI. */ 1672 bfd_vma insn = riscv_get_insn (howto->bitsize, 1673 contents + rel->r_offset); 1674 insn = (insn & ~MATCH_C_LUI) | MATCH_C_LI; 1675 riscv_put_insn (howto->bitsize, insn, contents + rel->r_offset); 1676 value = ENCODE_CITYPE_IMM (0); 1677 } 1678 else if (!VALID_CITYPE_LUI_IMM (RISCV_CONST_HIGH_PART (value))) 1679 return bfd_reloc_overflow; 1680 else 1681 value = ENCODE_CITYPE_LUI_IMM (RISCV_CONST_HIGH_PART (value)); 1682 break; 1683 1684 case R_RISCV_32: 1685 case R_RISCV_64: 1686 case R_RISCV_ADD8: 1687 case R_RISCV_ADD16: 1688 case R_RISCV_ADD32: 1689 case R_RISCV_ADD64: 1690 case R_RISCV_SUB6: 1691 case R_RISCV_SUB8: 1692 case R_RISCV_SUB16: 1693 case R_RISCV_SUB32: 1694 case R_RISCV_SUB64: 1695 case R_RISCV_SET6: 1696 case R_RISCV_SET8: 1697 case R_RISCV_SET16: 1698 case R_RISCV_SET32: 1699 case R_RISCV_32_PCREL: 1700 case R_RISCV_TLS_DTPREL32: 1701 case R_RISCV_TLS_DTPREL64: 1702 break; 1703 1704 case R_RISCV_DELETE: 1705 return bfd_reloc_ok; 1706 1707 default: 1708 return bfd_reloc_notsupported; 1709 } 1710 1711 bfd_vma word; 1712 if (riscv_is_insn_reloc (howto)) 1713 word = riscv_get_insn (howto->bitsize, contents + rel->r_offset); 1714 else 1715 word = bfd_get (howto->bitsize, input_bfd, contents + rel->r_offset); 1716 word = (word & ~howto->dst_mask) | (value & howto->dst_mask); 1717 if (riscv_is_insn_reloc (howto)) 1718 riscv_put_insn (howto->bitsize, word, contents + rel->r_offset); 1719 else 1720 bfd_put (howto->bitsize, input_bfd, word, contents + rel->r_offset); 1721 1722 return bfd_reloc_ok; 1723 } 1724 1725 /* Remember all PC-relative high-part relocs we've encountered to help us 1726 later resolve the corresponding low-part relocs. */ 1727 1728 typedef struct 1729 { 1730 /* PC value. */ 1731 bfd_vma address; 1732 /* Relocation value with addend. */ 1733 bfd_vma value; 1734 /* Original reloc type. */ 1735 int type; 1736 } riscv_pcrel_hi_reloc; 1737 1738 typedef struct riscv_pcrel_lo_reloc 1739 { 1740 /* PC value of auipc. */ 1741 bfd_vma address; 1742 /* Internal relocation. */ 1743 const Elf_Internal_Rela *reloc; 1744 /* Record the following information helps to resolve the %pcrel 1745 which cross different input section. For now we build a hash 1746 for pcrel at the start of riscv_elf_relocate_section, and then 1747 free the hash at the end. But riscv_elf_relocate_section only 1748 handles an input section at a time, so that means we can only 1749 resolve the %pcrel_hi and %pcrel_lo which are in the same input 1750 section. Otherwise, we will report dangerous relocation errors 1751 for those %pcrel which are not in the same input section. */ 1752 asection *input_section; 1753 struct bfd_link_info *info; 1754 reloc_howto_type *howto; 1755 bfd_byte *contents; 1756 /* The next riscv_pcrel_lo_reloc. */ 1757 struct riscv_pcrel_lo_reloc *next; 1758 } riscv_pcrel_lo_reloc; 1759 1760 typedef struct 1761 { 1762 /* Hash table for riscv_pcrel_hi_reloc. */ 1763 htab_t hi_relocs; 1764 /* Linked list for riscv_pcrel_lo_reloc. */ 1765 riscv_pcrel_lo_reloc *lo_relocs; 1766 } riscv_pcrel_relocs; 1767 1768 static hashval_t 1769 riscv_pcrel_reloc_hash (const void *entry) 1770 { 1771 const riscv_pcrel_hi_reloc *e = entry; 1772 return (hashval_t)(e->address >> 2); 1773 } 1774 1775 static int 1776 riscv_pcrel_reloc_eq (const void *entry1, const void *entry2) 1777 { 1778 const riscv_pcrel_hi_reloc *e1 = entry1, *e2 = entry2; 1779 return e1->address == e2->address; 1780 } 1781 1782 static bool 1783 riscv_init_pcrel_relocs (riscv_pcrel_relocs *p) 1784 { 1785 p->lo_relocs = NULL; 1786 p->hi_relocs = htab_create (1024, riscv_pcrel_reloc_hash, 1787 riscv_pcrel_reloc_eq, free); 1788 return p->hi_relocs != NULL; 1789 } 1790 1791 static void 1792 riscv_free_pcrel_relocs (riscv_pcrel_relocs *p) 1793 { 1794 riscv_pcrel_lo_reloc *cur = p->lo_relocs; 1795 1796 while (cur != NULL) 1797 { 1798 riscv_pcrel_lo_reloc *next = cur->next; 1799 free (cur); 1800 cur = next; 1801 } 1802 1803 htab_delete (p->hi_relocs); 1804 } 1805 1806 static bool 1807 riscv_zero_pcrel_hi_reloc (Elf_Internal_Rela *rel, 1808 struct bfd_link_info *info, 1809 bfd_vma pc, 1810 bfd_vma addr, 1811 bfd_byte *contents, 1812 const reloc_howto_type *howto) 1813 { 1814 /* We may need to reference low addreses in PC-relative modes even when the 1815 PC is far away from these addresses. For example, undefweak references 1816 need to produce the address 0 when linked. As 0 is far from the arbitrary 1817 addresses that we can link PC-relative programs at, the linker can't 1818 actually relocate references to those symbols. In order to allow these 1819 programs to work we simply convert the PC-relative auipc sequences to 1820 0-relative lui sequences. */ 1821 if (bfd_link_pic (info)) 1822 return false; 1823 1824 /* If it's possible to reference the symbol using auipc we do so, as that's 1825 more in the spirit of the PC-relative relocations we're processing. */ 1826 bfd_vma offset = addr - pc; 1827 if (ARCH_SIZE == 32 || VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (offset))) 1828 return false; 1829 1830 /* If it's impossible to reference this with a LUI-based offset then don't 1831 bother to convert it at all so users still see the PC-relative relocation 1832 in the truncation message. */ 1833 if (ARCH_SIZE > 32 && !VALID_UTYPE_IMM (RISCV_CONST_HIGH_PART (addr))) 1834 return false; 1835 1836 rel->r_info = ELFNN_R_INFO (addr, R_RISCV_HI20); 1837 1838 bfd_vma insn = riscv_get_insn (howto->bitsize, contents + rel->r_offset); 1839 insn = (insn & ~MASK_AUIPC) | MATCH_LUI; 1840 riscv_put_insn (howto->bitsize, insn, contents + rel->r_offset); 1841 return true; 1842 } 1843 1844 static bool 1845 riscv_record_pcrel_hi_reloc (riscv_pcrel_relocs *p, 1846 bfd_vma addr, 1847 bfd_vma value, 1848 int type, 1849 bool absolute) 1850 { 1851 bfd_vma offset = absolute ? value : value - addr; 1852 riscv_pcrel_hi_reloc entry = {addr, offset, type}; 1853 riscv_pcrel_hi_reloc **slot = 1854 (riscv_pcrel_hi_reloc **) htab_find_slot (p->hi_relocs, &entry, INSERT); 1855 1856 BFD_ASSERT (*slot == NULL); 1857 *slot = (riscv_pcrel_hi_reloc *) bfd_malloc (sizeof (riscv_pcrel_hi_reloc)); 1858 if (*slot == NULL) 1859 return false; 1860 **slot = entry; 1861 return true; 1862 } 1863 1864 static bool 1865 riscv_record_pcrel_lo_reloc (riscv_pcrel_relocs *p, 1866 bfd_vma addr, 1867 const Elf_Internal_Rela *reloc, 1868 asection *input_section, 1869 struct bfd_link_info *info, 1870 reloc_howto_type *howto, 1871 bfd_byte *contents) 1872 { 1873 riscv_pcrel_lo_reloc *entry; 1874 entry = (riscv_pcrel_lo_reloc *) bfd_malloc (sizeof (riscv_pcrel_lo_reloc)); 1875 if (entry == NULL) 1876 return false; 1877 *entry = (riscv_pcrel_lo_reloc) {addr, reloc, input_section, info, 1878 howto, contents, p->lo_relocs}; 1879 p->lo_relocs = entry; 1880 return true; 1881 } 1882 1883 static bool 1884 riscv_resolve_pcrel_lo_relocs (riscv_pcrel_relocs *p) 1885 { 1886 riscv_pcrel_lo_reloc *r; 1887 1888 for (r = p->lo_relocs; r != NULL; r = r->next) 1889 { 1890 bfd *input_bfd = r->input_section->owner; 1891 1892 riscv_pcrel_hi_reloc search = {r->address, 0, 0}; 1893 riscv_pcrel_hi_reloc *entry = htab_find (p->hi_relocs, &search); 1894 /* There may be a risk if the %pcrel_lo with addend refers to 1895 an IFUNC symbol. The %pcrel_hi has been relocated to plt, 1896 so the corresponding %pcrel_lo with addend looks wrong. */ 1897 char *string = NULL; 1898 if (entry == NULL) 1899 string = _("%pcrel_lo missing matching %pcrel_hi"); 1900 else if (entry->type == R_RISCV_GOT_HI20 1901 && r->reloc->r_addend != 0) 1902 string = _("%pcrel_lo with addend isn't allowed for R_RISCV_GOT_HI20"); 1903 else if (RISCV_CONST_HIGH_PART (entry->value) 1904 != RISCV_CONST_HIGH_PART (entry->value + r->reloc->r_addend)) 1905 { 1906 /* Check the overflow when adding reloc addend. */ 1907 if (asprintf (&string, 1908 _("%%pcrel_lo overflow with an addend, the " 1909 "value of %%pcrel_hi is 0x%" PRIx64 " without " 1910 "any addend, but may be 0x%" PRIx64 " after " 1911 "adding the %%pcrel_lo addend"), 1912 (int64_t) RISCV_CONST_HIGH_PART (entry->value), 1913 (int64_t) RISCV_CONST_HIGH_PART 1914 (entry->value + r->reloc->r_addend)) == -1) 1915 string = _("%pcrel_lo overflow with an addend"); 1916 } 1917 1918 if (string != NULL) 1919 { 1920 (*r->info->callbacks->reloc_dangerous) 1921 (r->info, string, input_bfd, r->input_section, r->reloc->r_offset); 1922 return true; 1923 } 1924 1925 perform_relocation (r->howto, r->reloc, entry->value, r->input_section, 1926 input_bfd, r->contents); 1927 } 1928 1929 return true; 1930 } 1931 1932 /* Relocate a RISC-V ELF section. 1933 1934 The RELOCATE_SECTION function is called by the new ELF backend linker 1935 to handle the relocations for a section. 1936 1937 The relocs are always passed as Rela structures. 1938 1939 This function is responsible for adjusting the section contents as 1940 necessary, and (if generating a relocatable output file) adjusting 1941 the reloc addend as necessary. 1942 1943 This function does not have to worry about setting the reloc 1944 address or the reloc symbol index. 1945 1946 LOCAL_SYMS is a pointer to the swapped in local symbols. 1947 1948 LOCAL_SECTIONS is an array giving the section in the input file 1949 corresponding to the st_shndx field of each local symbol. 1950 1951 The global hash table entry for the global symbols can be found 1952 via elf_sym_hashes (input_bfd). 1953 1954 When generating relocatable output, this function must handle 1955 STB_LOCAL/STT_SECTION symbols specially. The output symbol is 1956 going to be the section symbol corresponding to the output 1957 section, which means that the addend must be adjusted 1958 accordingly. */ 1959 1960 static int 1961 riscv_elf_relocate_section (bfd *output_bfd, 1962 struct bfd_link_info *info, 1963 bfd *input_bfd, 1964 asection *input_section, 1965 bfd_byte *contents, 1966 Elf_Internal_Rela *relocs, 1967 Elf_Internal_Sym *local_syms, 1968 asection **local_sections) 1969 { 1970 Elf_Internal_Rela *rel; 1971 Elf_Internal_Rela *relend; 1972 riscv_pcrel_relocs pcrel_relocs; 1973 bool ret = false; 1974 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info); 1975 Elf_Internal_Shdr *symtab_hdr = &elf_symtab_hdr (input_bfd); 1976 struct elf_link_hash_entry **sym_hashes = elf_sym_hashes (input_bfd); 1977 bfd_vma *local_got_offsets = elf_local_got_offsets (input_bfd); 1978 bool absolute; 1979 1980 if (!riscv_init_pcrel_relocs (&pcrel_relocs)) 1981 return false; 1982 1983 relend = relocs + input_section->reloc_count; 1984 for (rel = relocs; rel < relend; rel++) 1985 { 1986 unsigned long r_symndx; 1987 struct elf_link_hash_entry *h; 1988 Elf_Internal_Sym *sym; 1989 asection *sec; 1990 bfd_vma relocation; 1991 bfd_reloc_status_type r = bfd_reloc_ok; 1992 const char *name = NULL; 1993 bfd_vma off, ie_off; 1994 bool unresolved_reloc, is_ie = false; 1995 bfd_vma pc = sec_addr (input_section) + rel->r_offset; 1996 int r_type = ELFNN_R_TYPE (rel->r_info), tls_type; 1997 reloc_howto_type *howto = riscv_elf_rtype_to_howto (input_bfd, r_type); 1998 const char *msg = NULL; 1999 char *msg_buf = NULL; 2000 bool resolved_to_zero; 2001 2002 if (howto == NULL) 2003 continue; 2004 2005 /* This is a final link. */ 2006 r_symndx = ELFNN_R_SYM (rel->r_info); 2007 h = NULL; 2008 sym = NULL; 2009 sec = NULL; 2010 unresolved_reloc = false; 2011 if (r_symndx < symtab_hdr->sh_info) 2012 { 2013 sym = local_syms + r_symndx; 2014 sec = local_sections[r_symndx]; 2015 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel); 2016 2017 /* Relocate against local STT_GNU_IFUNC symbol. */ 2018 if (!bfd_link_relocatable (info) 2019 && ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC) 2020 { 2021 h = riscv_elf_get_local_sym_hash (htab, input_bfd, rel, false); 2022 if (h == NULL) 2023 abort (); 2024 2025 /* Set STT_GNU_IFUNC symbol value. */ 2026 h->root.u.def.value = sym->st_value; 2027 h->root.u.def.section = sec; 2028 } 2029 } 2030 else 2031 { 2032 bool warned, ignored; 2033 2034 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 2035 r_symndx, symtab_hdr, sym_hashes, 2036 h, sec, relocation, 2037 unresolved_reloc, warned, ignored); 2038 if (warned) 2039 { 2040 /* To avoid generating warning messages about truncated 2041 relocations, set the relocation's address to be the same as 2042 the start of this section. */ 2043 if (input_section->output_section != NULL) 2044 relocation = input_section->output_section->vma; 2045 else 2046 relocation = 0; 2047 } 2048 } 2049 2050 if (sec != NULL && discarded_section (sec)) 2051 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section, 2052 rel, 1, relend, howto, 0, contents); 2053 2054 if (bfd_link_relocatable (info)) 2055 continue; 2056 2057 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle 2058 it here if it is defined in a non-shared object. */ 2059 if (h != NULL 2060 && h->type == STT_GNU_IFUNC 2061 && h->def_regular) 2062 { 2063 asection *plt, *base_got; 2064 2065 if ((input_section->flags & SEC_ALLOC) == 0) 2066 { 2067 /* If this is a SHT_NOTE section without SHF_ALLOC, treat 2068 STT_GNU_IFUNC symbol as STT_FUNC. */ 2069 if (elf_section_type (input_section) == SHT_NOTE) 2070 goto skip_ifunc; 2071 2072 /* Dynamic relocs are not propagated for SEC_DEBUGGING 2073 sections because such sections are not SEC_ALLOC and 2074 thus ld.so will not process them. */ 2075 if ((input_section->flags & SEC_DEBUGGING) != 0) 2076 continue; 2077 2078 abort (); 2079 } 2080 else if (h->plt.offset == (bfd_vma) -1 2081 /* The following relocation may not need the .plt entries 2082 when all references to a STT_GNU_IFUNC symbols are done 2083 via GOT or static function pointers. */ 2084 && r_type != R_RISCV_32 2085 && r_type != R_RISCV_64 2086 && r_type != R_RISCV_HI20 2087 && r_type != R_RISCV_GOT_HI20 2088 && r_type != R_RISCV_LO12_I 2089 && r_type != R_RISCV_LO12_S) 2090 goto bad_ifunc_reloc; 2091 2092 /* STT_GNU_IFUNC symbol must go through PLT. */ 2093 plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt; 2094 relocation = plt->output_section->vma 2095 + plt->output_offset 2096 + h->plt.offset; 2097 2098 switch (r_type) 2099 { 2100 case R_RISCV_32: 2101 case R_RISCV_64: 2102 if (rel->r_addend != 0) 2103 { 2104 if (h->root.root.string) 2105 name = h->root.root.string; 2106 else 2107 name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym, NULL); 2108 2109 _bfd_error_handler 2110 /* xgettext:c-format */ 2111 (_("%pB: relocation %s against STT_GNU_IFUNC " 2112 "symbol `%s' has non-zero addend: %" PRId64), 2113 input_bfd, howto->name, name, (int64_t) rel->r_addend); 2114 bfd_set_error (bfd_error_bad_value); 2115 return false; 2116 } 2117 2118 /* Generate dynamic relocation only when there is a non-GOT 2119 reference in a shared object or there is no PLT. */ 2120 if ((bfd_link_pic (info) && h->non_got_ref) 2121 || h->plt.offset == (bfd_vma) -1) 2122 { 2123 Elf_Internal_Rela outrel; 2124 asection *sreloc; 2125 2126 /* Need a dynamic relocation to get the real function 2127 address. */ 2128 outrel.r_offset = _bfd_elf_section_offset (output_bfd, 2129 info, 2130 input_section, 2131 rel->r_offset); 2132 if (outrel.r_offset == (bfd_vma) -1 2133 || outrel.r_offset == (bfd_vma) -2) 2134 abort (); 2135 2136 outrel.r_offset += input_section->output_section->vma 2137 + input_section->output_offset; 2138 2139 if (h->dynindx == -1 2140 || h->forced_local 2141 || bfd_link_executable (info)) 2142 { 2143 info->callbacks->minfo 2144 (_("Local IFUNC function `%s' in %pB\n"), 2145 h->root.root.string, 2146 h->root.u.def.section->owner); 2147 2148 /* This symbol is resolved locally. */ 2149 outrel.r_info = ELFNN_R_INFO (0, R_RISCV_IRELATIVE); 2150 outrel.r_addend = h->root.u.def.value 2151 + h->root.u.def.section->output_section->vma 2152 + h->root.u.def.section->output_offset; 2153 } 2154 else 2155 { 2156 outrel.r_info = ELFNN_R_INFO (h->dynindx, r_type); 2157 outrel.r_addend = 0; 2158 } 2159 2160 /* Dynamic relocations are stored in 2161 1. .rela.ifunc section in PIC object. 2162 2. .rela.got section in dynamic executable. 2163 3. .rela.iplt section in static executable. */ 2164 if (bfd_link_pic (info)) 2165 sreloc = htab->elf.irelifunc; 2166 else if (htab->elf.splt != NULL) 2167 sreloc = htab->elf.srelgot; 2168 else 2169 sreloc = htab->elf.irelplt; 2170 2171 riscv_elf_append_rela (output_bfd, sreloc, &outrel); 2172 2173 /* If this reloc is against an external symbol, we 2174 do not want to fiddle with the addend. Otherwise, 2175 we need to include the symbol value so that it 2176 becomes an addend for the dynamic reloc. For an 2177 internal symbol, we have updated addend. */ 2178 continue; 2179 } 2180 goto do_relocation; 2181 2182 case R_RISCV_GOT_HI20: 2183 base_got = htab->elf.sgot; 2184 off = h->got.offset; 2185 2186 if (base_got == NULL) 2187 abort (); 2188 2189 if (off == (bfd_vma) -1) 2190 { 2191 bfd_vma plt_idx; 2192 2193 /* We can't use h->got.offset here to save state, or 2194 even just remember the offset, as finish_dynamic_symbol 2195 would use that as offset into .got. */ 2196 2197 if (htab->elf.splt != NULL) 2198 { 2199 plt_idx = (h->plt.offset - PLT_HEADER_SIZE) 2200 / PLT_ENTRY_SIZE; 2201 off = GOTPLT_HEADER_SIZE + (plt_idx * GOT_ENTRY_SIZE); 2202 base_got = htab->elf.sgotplt; 2203 } 2204 else 2205 { 2206 plt_idx = h->plt.offset / PLT_ENTRY_SIZE; 2207 off = plt_idx * GOT_ENTRY_SIZE; 2208 base_got = htab->elf.igotplt; 2209 } 2210 2211 if (h->dynindx == -1 2212 || h->forced_local 2213 || info->symbolic) 2214 { 2215 /* This references the local definition. We must 2216 initialize this entry in the global offset table. 2217 Since the offset must always be a multiple of 8, 2218 we use the least significant bit to record 2219 whether we have initialized it already. 2220 2221 When doing a dynamic link, we create a .rela.got 2222 relocation entry to initialize the value. This 2223 is done in the finish_dynamic_symbol routine. */ 2224 if ((off & 1) != 0) 2225 off &= ~1; 2226 else 2227 { 2228 bfd_put_NN (output_bfd, relocation, 2229 base_got->contents + off); 2230 /* Note that this is harmless for the case, 2231 as -1 | 1 still is -1. */ 2232 h->got.offset |= 1; 2233 } 2234 } 2235 } 2236 2237 relocation = base_got->output_section->vma 2238 + base_got->output_offset + off; 2239 2240 if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc, 2241 relocation, r_type, 2242 false)) 2243 r = bfd_reloc_overflow; 2244 goto do_relocation; 2245 2246 case R_RISCV_CALL: 2247 case R_RISCV_CALL_PLT: 2248 case R_RISCV_HI20: 2249 case R_RISCV_LO12_I: 2250 case R_RISCV_LO12_S: 2251 goto do_relocation; 2252 2253 case R_RISCV_PCREL_HI20: 2254 if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc, 2255 relocation, r_type, 2256 false)) 2257 r = bfd_reloc_overflow; 2258 goto do_relocation; 2259 2260 default: 2261 bad_ifunc_reloc: 2262 if (h->root.root.string) 2263 name = h->root.root.string; 2264 else 2265 /* The entry of local ifunc is fake in global hash table, 2266 we should find the name by the original local symbol. */ 2267 name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym, NULL); 2268 2269 _bfd_error_handler 2270 /* xgettext:c-format */ 2271 (_("%pB: relocation %s against STT_GNU_IFUNC " 2272 "symbol `%s' isn't supported"), input_bfd, 2273 howto->name, name); 2274 bfd_set_error (bfd_error_bad_value); 2275 return false; 2276 } 2277 } 2278 2279 skip_ifunc: 2280 if (h != NULL) 2281 name = h->root.root.string; 2282 else 2283 { 2284 name = (bfd_elf_string_from_elf_section 2285 (input_bfd, symtab_hdr->sh_link, sym->st_name)); 2286 if (name == NULL || *name == '\0') 2287 name = bfd_section_name (sec); 2288 } 2289 2290 resolved_to_zero = (h != NULL 2291 && UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)); 2292 2293 switch (r_type) 2294 { 2295 case R_RISCV_NONE: 2296 case R_RISCV_RELAX: 2297 case R_RISCV_TPREL_ADD: 2298 case R_RISCV_COPY: 2299 case R_RISCV_JUMP_SLOT: 2300 case R_RISCV_RELATIVE: 2301 /* These require nothing of us at all. */ 2302 continue; 2303 2304 case R_RISCV_HI20: 2305 case R_RISCV_BRANCH: 2306 case R_RISCV_RVC_BRANCH: 2307 case R_RISCV_RVC_LUI: 2308 case R_RISCV_LO12_I: 2309 case R_RISCV_LO12_S: 2310 case R_RISCV_SET6: 2311 case R_RISCV_SET8: 2312 case R_RISCV_SET16: 2313 case R_RISCV_SET32: 2314 case R_RISCV_32_PCREL: 2315 case R_RISCV_DELETE: 2316 /* These require no special handling beyond perform_relocation. */ 2317 break; 2318 2319 case R_RISCV_GOT_HI20: 2320 if (h != NULL) 2321 { 2322 bool dyn, pic; 2323 2324 off = h->got.offset; 2325 BFD_ASSERT (off != (bfd_vma) -1); 2326 dyn = elf_hash_table (info)->dynamic_sections_created; 2327 pic = bfd_link_pic (info); 2328 2329 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, pic, h) 2330 || (pic && SYMBOL_REFERENCES_LOCAL (info, h))) 2331 { 2332 /* This is actually a static link, or it is a 2333 -Bsymbolic link and the symbol is defined 2334 locally, or the symbol was forced to be local 2335 because of a version file. We must initialize 2336 this entry in the global offset table. Since the 2337 offset must always be a multiple of the word size, 2338 we use the least significant bit to record whether 2339 we have initialized it already. 2340 2341 When doing a dynamic link, we create a .rela.got 2342 relocation entry to initialize the value. This 2343 is done in the finish_dynamic_symbol routine. */ 2344 if ((off & 1) != 0) 2345 off &= ~1; 2346 else 2347 { 2348 bfd_put_NN (output_bfd, relocation, 2349 htab->elf.sgot->contents + off); 2350 h->got.offset |= 1; 2351 } 2352 } 2353 else 2354 unresolved_reloc = false; 2355 } 2356 else 2357 { 2358 BFD_ASSERT (local_got_offsets != NULL 2359 && local_got_offsets[r_symndx] != (bfd_vma) -1); 2360 2361 off = local_got_offsets[r_symndx]; 2362 2363 /* The offset must always be a multiple of the word size. 2364 So, we can use the least significant bit to record 2365 whether we have already processed this entry. */ 2366 if ((off & 1) != 0) 2367 off &= ~1; 2368 else 2369 { 2370 if (bfd_link_pic (info)) 2371 { 2372 asection *s; 2373 Elf_Internal_Rela outrel; 2374 2375 /* We need to generate a R_RISCV_RELATIVE reloc 2376 for the dynamic linker. */ 2377 s = htab->elf.srelgot; 2378 BFD_ASSERT (s != NULL); 2379 2380 outrel.r_offset = sec_addr (htab->elf.sgot) + off; 2381 outrel.r_info = 2382 ELFNN_R_INFO (0, R_RISCV_RELATIVE); 2383 outrel.r_addend = relocation; 2384 relocation = 0; 2385 riscv_elf_append_rela (output_bfd, s, &outrel); 2386 } 2387 2388 bfd_put_NN (output_bfd, relocation, 2389 htab->elf.sgot->contents + off); 2390 local_got_offsets[r_symndx] |= 1; 2391 } 2392 } 2393 2394 if (rel->r_addend != 0) 2395 { 2396 msg = _("The addend isn't allowed for R_RISCV_GOT_HI20"); 2397 r = bfd_reloc_dangerous; 2398 } 2399 else 2400 { 2401 /* Address of got entry. */ 2402 relocation = sec_addr (htab->elf.sgot) + off; 2403 absolute = riscv_zero_pcrel_hi_reloc (rel, info, pc, 2404 relocation, contents, 2405 howto); 2406 /* Update howto if relocation is changed. */ 2407 howto = riscv_elf_rtype_to_howto (input_bfd, 2408 ELFNN_R_TYPE (rel->r_info)); 2409 if (howto == NULL) 2410 r = bfd_reloc_notsupported; 2411 else if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc, 2412 relocation, r_type, 2413 absolute)) 2414 r = bfd_reloc_overflow; 2415 } 2416 break; 2417 2418 case R_RISCV_ADD8: 2419 case R_RISCV_ADD16: 2420 case R_RISCV_ADD32: 2421 case R_RISCV_ADD64: 2422 { 2423 bfd_vma old_value = bfd_get (howto->bitsize, input_bfd, 2424 contents + rel->r_offset); 2425 relocation = old_value + relocation; 2426 } 2427 break; 2428 2429 case R_RISCV_SUB6: 2430 { 2431 bfd_vma old_value = bfd_get (howto->bitsize, input_bfd, 2432 contents + rel->r_offset); 2433 relocation = (old_value & ~howto->dst_mask) 2434 | (((old_value & howto->dst_mask) - relocation) 2435 & howto->dst_mask); 2436 } 2437 break; 2438 2439 case R_RISCV_SUB8: 2440 case R_RISCV_SUB16: 2441 case R_RISCV_SUB32: 2442 case R_RISCV_SUB64: 2443 { 2444 bfd_vma old_value = bfd_get (howto->bitsize, input_bfd, 2445 contents + rel->r_offset); 2446 relocation = old_value - relocation; 2447 } 2448 break; 2449 2450 case R_RISCV_CALL: 2451 case R_RISCV_CALL_PLT: 2452 /* Handle a call to an undefined weak function. This won't be 2453 relaxed, so we have to handle it here. */ 2454 if (h != NULL && h->root.type == bfd_link_hash_undefweak 2455 && (!bfd_link_pic (info) || h->plt.offset == MINUS_ONE)) 2456 { 2457 /* We can use x0 as the base register. */ 2458 bfd_vma insn = bfd_getl32 (contents + rel->r_offset + 4); 2459 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 2460 bfd_putl32 (insn, contents + rel->r_offset + 4); 2461 /* Set the relocation value so that we get 0 after the pc 2462 relative adjustment. */ 2463 relocation = sec_addr (input_section) + rel->r_offset; 2464 } 2465 /* Fall through. */ 2466 2467 case R_RISCV_JAL: 2468 case R_RISCV_RVC_JUMP: 2469 if (bfd_link_pic (info) && h != NULL) 2470 { 2471 if (h->plt.offset != MINUS_ONE) 2472 { 2473 /* Refer to the PLT entry. This check has to match the 2474 check in _bfd_riscv_relax_section. */ 2475 relocation = sec_addr (htab->elf.splt) + h->plt.offset; 2476 unresolved_reloc = false; 2477 } 2478 else if (!SYMBOL_REFERENCES_LOCAL (info, h) 2479 && (input_section->flags & SEC_ALLOC) != 0 2480 && (input_section->flags & SEC_READONLY) != 0 2481 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT) 2482 { 2483 /* PR 28509, when generating the shared object, these 2484 referenced symbols may bind externally, which means 2485 they will be exported to the dynamic symbol table, 2486 and are preemptible by default. These symbols cannot 2487 be referenced by the non-pic relocations, like 2488 R_RISCV_JAL and R_RISCV_RVC_JUMP relocations. 2489 2490 However, consider that linker may relax the R_RISCV_CALL 2491 relocations to R_RISCV_JAL or R_RISCV_RVC_JUMP, if 2492 these relocations are relocated to the plt entries, 2493 then we won't report error for them. 2494 2495 Perhaps we also need the similar checks for the 2496 R_RISCV_BRANCH and R_RISCV_RVC_BRANCH relocations. */ 2497 if (asprintf (&msg_buf, 2498 _("%%X%%P: relocation %s against `%s' which " 2499 "may bind externally can not be used when " 2500 "making a shared object; recompile " 2501 "with -fPIC\n"), 2502 howto->name, h->root.root.string) == -1) 2503 msg_buf = NULL; 2504 msg = msg_buf; 2505 r = bfd_reloc_notsupported; 2506 } 2507 } 2508 break; 2509 2510 case R_RISCV_TPREL_HI20: 2511 relocation = tpoff (info, relocation); 2512 break; 2513 2514 case R_RISCV_TPREL_LO12_I: 2515 case R_RISCV_TPREL_LO12_S: 2516 relocation = tpoff (info, relocation); 2517 break; 2518 2519 case R_RISCV_TPREL_I: 2520 case R_RISCV_TPREL_S: 2521 relocation = tpoff (info, relocation); 2522 if (VALID_ITYPE_IMM (relocation + rel->r_addend)) 2523 { 2524 /* We can use tp as the base register. */ 2525 bfd_vma insn = bfd_getl32 (contents + rel->r_offset); 2526 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 2527 insn |= X_TP << OP_SH_RS1; 2528 bfd_putl32 (insn, contents + rel->r_offset); 2529 } 2530 else 2531 r = bfd_reloc_overflow; 2532 break; 2533 2534 case R_RISCV_GPREL_I: 2535 case R_RISCV_GPREL_S: 2536 { 2537 bfd_vma gp = riscv_global_pointer_value (info); 2538 bool x0_base = VALID_ITYPE_IMM (relocation + rel->r_addend); 2539 if (x0_base || VALID_ITYPE_IMM (relocation + rel->r_addend - gp)) 2540 { 2541 /* We can use x0 or gp as the base register. */ 2542 bfd_vma insn = bfd_getl32 (contents + rel->r_offset); 2543 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 2544 if (!x0_base) 2545 { 2546 rel->r_addend -= gp; 2547 insn |= X_GP << OP_SH_RS1; 2548 } 2549 bfd_putl32 (insn, contents + rel->r_offset); 2550 } 2551 else 2552 r = bfd_reloc_overflow; 2553 break; 2554 } 2555 2556 case R_RISCV_PCREL_HI20: 2557 absolute = riscv_zero_pcrel_hi_reloc (rel, info, pc, relocation, 2558 contents, howto); 2559 /* Update howto if relocation is changed. */ 2560 howto = riscv_elf_rtype_to_howto (input_bfd, 2561 ELFNN_R_TYPE (rel->r_info)); 2562 if (howto == NULL) 2563 r = bfd_reloc_notsupported; 2564 else if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc, 2565 relocation + rel->r_addend, 2566 r_type, absolute)) 2567 r = bfd_reloc_overflow; 2568 break; 2569 2570 case R_RISCV_PCREL_LO12_I: 2571 case R_RISCV_PCREL_LO12_S: 2572 /* We don't allow section symbols plus addends as the auipc address, 2573 because then riscv_relax_delete_bytes would have to search through 2574 all relocs to update these addends. This is also ambiguous, as 2575 we do allow offsets to be added to the target address, which are 2576 not to be used to find the auipc address. */ 2577 if (((sym != NULL && (ELF_ST_TYPE (sym->st_info) == STT_SECTION)) 2578 || (h != NULL && h->type == STT_SECTION)) 2579 && rel->r_addend) 2580 { 2581 msg = _("%pcrel_lo section symbol with an addend"); 2582 r = bfd_reloc_dangerous; 2583 break; 2584 } 2585 2586 if (riscv_record_pcrel_lo_reloc (&pcrel_relocs, relocation, rel, 2587 input_section, info, howto, 2588 contents)) 2589 continue; 2590 r = bfd_reloc_overflow; 2591 break; 2592 2593 case R_RISCV_TLS_DTPREL32: 2594 case R_RISCV_TLS_DTPREL64: 2595 relocation = dtpoff (info, relocation); 2596 break; 2597 2598 case R_RISCV_32: 2599 case R_RISCV_64: 2600 if ((input_section->flags & SEC_ALLOC) == 0) 2601 break; 2602 2603 if ((bfd_link_pic (info) 2604 && (h == NULL 2605 || (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 2606 && !resolved_to_zero) 2607 || h->root.type != bfd_link_hash_undefweak) 2608 && (!howto->pc_relative 2609 || !SYMBOL_CALLS_LOCAL (info, h))) 2610 || (!bfd_link_pic (info) 2611 && h != NULL 2612 && h->dynindx != -1 2613 && !h->non_got_ref 2614 && ((h->def_dynamic 2615 && !h->def_regular) 2616 || h->root.type == bfd_link_hash_undefweak 2617 || h->root.type == bfd_link_hash_undefined))) 2618 { 2619 Elf_Internal_Rela outrel; 2620 asection *sreloc; 2621 bool skip_static_relocation, skip_dynamic_relocation; 2622 2623 /* When generating a shared object, these relocations 2624 are copied into the output file to be resolved at run 2625 time. */ 2626 2627 outrel.r_offset = 2628 _bfd_elf_section_offset (output_bfd, info, input_section, 2629 rel->r_offset); 2630 skip_static_relocation = outrel.r_offset != (bfd_vma) -2; 2631 skip_dynamic_relocation = outrel.r_offset >= (bfd_vma) -2; 2632 outrel.r_offset += sec_addr (input_section); 2633 2634 if (skip_dynamic_relocation) 2635 memset (&outrel, 0, sizeof outrel); 2636 else if (h != NULL && h->dynindx != -1 2637 && !(bfd_link_pic (info) 2638 && SYMBOLIC_BIND (info, h) 2639 && h->def_regular)) 2640 { 2641 outrel.r_info = ELFNN_R_INFO (h->dynindx, r_type); 2642 outrel.r_addend = rel->r_addend; 2643 } 2644 else 2645 { 2646 outrel.r_info = ELFNN_R_INFO (0, R_RISCV_RELATIVE); 2647 outrel.r_addend = relocation + rel->r_addend; 2648 } 2649 2650 sreloc = elf_section_data (input_section)->sreloc; 2651 riscv_elf_append_rela (output_bfd, sreloc, &outrel); 2652 if (skip_static_relocation) 2653 continue; 2654 } 2655 break; 2656 2657 case R_RISCV_TLS_GOT_HI20: 2658 is_ie = true; 2659 /* Fall through. */ 2660 2661 case R_RISCV_TLS_GD_HI20: 2662 if (h != NULL) 2663 { 2664 off = h->got.offset; 2665 h->got.offset |= 1; 2666 } 2667 else 2668 { 2669 off = local_got_offsets[r_symndx]; 2670 local_got_offsets[r_symndx] |= 1; 2671 } 2672 2673 tls_type = _bfd_riscv_elf_tls_type (input_bfd, h, r_symndx); 2674 BFD_ASSERT (tls_type & (GOT_TLS_IE | GOT_TLS_GD)); 2675 /* If this symbol is referenced by both GD and IE TLS, the IE 2676 reference's GOT slot follows the GD reference's slots. */ 2677 ie_off = 0; 2678 if ((tls_type & GOT_TLS_GD) && (tls_type & GOT_TLS_IE)) 2679 ie_off = 2 * GOT_ENTRY_SIZE; 2680 2681 if ((off & 1) != 0) 2682 off &= ~1; 2683 else 2684 { 2685 Elf_Internal_Rela outrel; 2686 int indx = 0; 2687 bool need_relocs = false; 2688 2689 if (htab->elf.srelgot == NULL) 2690 abort (); 2691 2692 if (h != NULL) 2693 { 2694 bool dyn, pic; 2695 dyn = htab->elf.dynamic_sections_created; 2696 pic = bfd_link_pic (info); 2697 2698 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, pic, h) 2699 && (!pic || !SYMBOL_REFERENCES_LOCAL (info, h))) 2700 indx = h->dynindx; 2701 } 2702 2703 /* The GOT entries have not been initialized yet. Do it 2704 now, and emit any relocations. */ 2705 if ((bfd_link_pic (info) || indx != 0) 2706 && (h == NULL 2707 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 2708 || h->root.type != bfd_link_hash_undefweak)) 2709 need_relocs = true; 2710 2711 if (tls_type & GOT_TLS_GD) 2712 { 2713 if (need_relocs) 2714 { 2715 outrel.r_offset = sec_addr (htab->elf.sgot) + off; 2716 outrel.r_addend = 0; 2717 outrel.r_info = ELFNN_R_INFO (indx, R_RISCV_TLS_DTPMODNN); 2718 bfd_put_NN (output_bfd, 0, 2719 htab->elf.sgot->contents + off); 2720 riscv_elf_append_rela (output_bfd, htab->elf.srelgot, &outrel); 2721 if (indx == 0) 2722 { 2723 BFD_ASSERT (! unresolved_reloc); 2724 bfd_put_NN (output_bfd, 2725 dtpoff (info, relocation), 2726 (htab->elf.sgot->contents 2727 + off + RISCV_ELF_WORD_BYTES)); 2728 } 2729 else 2730 { 2731 bfd_put_NN (output_bfd, 0, 2732 (htab->elf.sgot->contents 2733 + off + RISCV_ELF_WORD_BYTES)); 2734 outrel.r_info = ELFNN_R_INFO (indx, R_RISCV_TLS_DTPRELNN); 2735 outrel.r_offset += RISCV_ELF_WORD_BYTES; 2736 riscv_elf_append_rela (output_bfd, htab->elf.srelgot, &outrel); 2737 } 2738 } 2739 else 2740 { 2741 /* If we are not emitting relocations for a 2742 general dynamic reference, then we must be in a 2743 static link or an executable link with the 2744 symbol binding locally. Mark it as belonging 2745 to module 1, the executable. */ 2746 bfd_put_NN (output_bfd, 1, 2747 htab->elf.sgot->contents + off); 2748 bfd_put_NN (output_bfd, 2749 dtpoff (info, relocation), 2750 (htab->elf.sgot->contents 2751 + off + RISCV_ELF_WORD_BYTES)); 2752 } 2753 } 2754 2755 if (tls_type & GOT_TLS_IE) 2756 { 2757 if (need_relocs) 2758 { 2759 bfd_put_NN (output_bfd, 0, 2760 htab->elf.sgot->contents + off + ie_off); 2761 outrel.r_offset = sec_addr (htab->elf.sgot) 2762 + off + ie_off; 2763 outrel.r_addend = 0; 2764 if (indx == 0) 2765 outrel.r_addend = tpoff (info, relocation); 2766 outrel.r_info = ELFNN_R_INFO (indx, R_RISCV_TLS_TPRELNN); 2767 riscv_elf_append_rela (output_bfd, htab->elf.srelgot, &outrel); 2768 } 2769 else 2770 { 2771 bfd_put_NN (output_bfd, tpoff (info, relocation), 2772 htab->elf.sgot->contents + off + ie_off); 2773 } 2774 } 2775 } 2776 2777 BFD_ASSERT (off < (bfd_vma) -2); 2778 relocation = sec_addr (htab->elf.sgot) + off + (is_ie ? ie_off : 0); 2779 if (!riscv_record_pcrel_hi_reloc (&pcrel_relocs, pc, 2780 relocation, r_type, 2781 false)) 2782 r = bfd_reloc_overflow; 2783 unresolved_reloc = false; 2784 break; 2785 2786 default: 2787 r = bfd_reloc_notsupported; 2788 } 2789 2790 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections 2791 because such sections are not SEC_ALLOC and thus ld.so will 2792 not process them. */ 2793 if (unresolved_reloc 2794 && !((input_section->flags & SEC_DEBUGGING) != 0 2795 && h->def_dynamic) 2796 && _bfd_elf_section_offset (output_bfd, info, input_section, 2797 rel->r_offset) != (bfd_vma) -1) 2798 { 2799 if (asprintf (&msg_buf, 2800 _("%%X%%P: unresolvable %s relocation against " 2801 "symbol `%s'\n"), 2802 howto->name, 2803 h->root.root.string) == -1) 2804 msg_buf = NULL; 2805 msg = msg_buf; 2806 r = bfd_reloc_notsupported; 2807 } 2808 2809 do_relocation: 2810 if (r == bfd_reloc_ok) 2811 r = perform_relocation (howto, rel, relocation, input_section, 2812 input_bfd, contents); 2813 2814 /* We should have already detected the error and set message before. 2815 If the error message isn't set since the linker runs out of memory 2816 or we don't set it before, then we should set the default message 2817 with the "internal error" string here. */ 2818 switch (r) 2819 { 2820 case bfd_reloc_ok: 2821 continue; 2822 2823 case bfd_reloc_overflow: 2824 info->callbacks->reloc_overflow 2825 (info, (h ? &h->root : NULL), name, howto->name, 2826 (bfd_vma) 0, input_bfd, input_section, rel->r_offset); 2827 break; 2828 2829 case bfd_reloc_undefined: 2830 info->callbacks->undefined_symbol 2831 (info, name, input_bfd, input_section, rel->r_offset, 2832 true); 2833 break; 2834 2835 case bfd_reloc_outofrange: 2836 if (msg == NULL) 2837 msg = _("%X%P: internal error: out of range error\n"); 2838 break; 2839 2840 case bfd_reloc_notsupported: 2841 if (msg == NULL) 2842 msg = _("%X%P: internal error: unsupported relocation error\n"); 2843 break; 2844 2845 case bfd_reloc_dangerous: 2846 /* The error message should already be set. */ 2847 if (msg == NULL) 2848 msg = _("dangerous relocation error"); 2849 info->callbacks->reloc_dangerous 2850 (info, msg, input_bfd, input_section, rel->r_offset); 2851 break; 2852 2853 default: 2854 msg = _("%X%P: internal error: unknown error\n"); 2855 break; 2856 } 2857 2858 /* Do not report error message for the dangerous relocation again. */ 2859 if (msg && r != bfd_reloc_dangerous) 2860 info->callbacks->einfo (msg); 2861 2862 /* Free the unused `msg_buf`. */ 2863 free (msg_buf); 2864 2865 /* We already reported the error via a callback, so don't try to report 2866 it again by returning false. That leads to spurious errors. */ 2867 ret = true; 2868 goto out; 2869 } 2870 2871 ret = riscv_resolve_pcrel_lo_relocs (&pcrel_relocs); 2872 out: 2873 riscv_free_pcrel_relocs (&pcrel_relocs); 2874 return ret; 2875 } 2876 2877 /* Finish up dynamic symbol handling. We set the contents of various 2878 dynamic sections here. */ 2879 2880 static bool 2881 riscv_elf_finish_dynamic_symbol (bfd *output_bfd, 2882 struct bfd_link_info *info, 2883 struct elf_link_hash_entry *h, 2884 Elf_Internal_Sym *sym) 2885 { 2886 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info); 2887 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd); 2888 2889 if (h->plt.offset != (bfd_vma) -1) 2890 { 2891 /* We've decided to create a PLT entry for this symbol. */ 2892 bfd_byte *loc; 2893 bfd_vma i, header_address, plt_idx, got_offset, got_address; 2894 uint32_t plt_entry[PLT_ENTRY_INSNS]; 2895 Elf_Internal_Rela rela; 2896 asection *plt, *gotplt, *relplt; 2897 2898 /* When building a static executable, use .iplt, .igot.plt and 2899 .rela.iplt sections for STT_GNU_IFUNC symbols. */ 2900 if (htab->elf.splt != NULL) 2901 { 2902 plt = htab->elf.splt; 2903 gotplt = htab->elf.sgotplt; 2904 relplt = htab->elf.srelplt; 2905 } 2906 else 2907 { 2908 plt = htab->elf.iplt; 2909 gotplt = htab->elf.igotplt; 2910 relplt = htab->elf.irelplt; 2911 } 2912 2913 /* This symbol has an entry in the procedure linkage table. Set 2914 it up. */ 2915 if ((h->dynindx == -1 2916 && !((h->forced_local || bfd_link_executable (info)) 2917 && h->def_regular 2918 && h->type == STT_GNU_IFUNC)) 2919 || plt == NULL 2920 || gotplt == NULL 2921 || relplt == NULL) 2922 return false; 2923 2924 /* Calculate the address of the PLT header. */ 2925 header_address = sec_addr (plt); 2926 2927 /* Calculate the index of the entry and the offset of .got.plt entry. 2928 For static executables, we don't reserve anything. */ 2929 if (plt == htab->elf.splt) 2930 { 2931 plt_idx = (h->plt.offset - PLT_HEADER_SIZE) / PLT_ENTRY_SIZE; 2932 got_offset = GOTPLT_HEADER_SIZE + (plt_idx * GOT_ENTRY_SIZE); 2933 } 2934 else 2935 { 2936 plt_idx = h->plt.offset / PLT_ENTRY_SIZE; 2937 got_offset = plt_idx * GOT_ENTRY_SIZE; 2938 } 2939 2940 /* Calculate the address of the .got.plt entry. */ 2941 got_address = sec_addr (gotplt) + got_offset; 2942 2943 /* Find out where the .plt entry should go. */ 2944 loc = plt->contents + h->plt.offset; 2945 2946 /* Fill in the PLT entry itself. */ 2947 if (! riscv_make_plt_entry (output_bfd, got_address, 2948 header_address + h->plt.offset, 2949 plt_entry)) 2950 return false; 2951 2952 for (i = 0; i < PLT_ENTRY_INSNS; i++) 2953 bfd_putl32 (plt_entry[i], loc + 4*i); 2954 2955 /* Fill in the initial value of the .got.plt entry. */ 2956 loc = gotplt->contents + (got_address - sec_addr (gotplt)); 2957 bfd_put_NN (output_bfd, sec_addr (plt), loc); 2958 2959 rela.r_offset = got_address; 2960 2961 if (h->dynindx == -1 2962 || ((bfd_link_executable (info) 2963 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT) 2964 && h->def_regular 2965 && h->type == STT_GNU_IFUNC)) 2966 { 2967 info->callbacks->minfo (_("Local IFUNC function `%s' in %pB\n"), 2968 h->root.root.string, 2969 h->root.u.def.section->owner); 2970 2971 /* If an STT_GNU_IFUNC symbol is locally defined, generate 2972 R_RISCV_IRELATIVE instead of R_RISCV_JUMP_SLOT. */ 2973 asection *sec = h->root.u.def.section; 2974 rela.r_info = ELFNN_R_INFO (0, R_RISCV_IRELATIVE); 2975 rela.r_addend = h->root.u.def.value 2976 + sec->output_section->vma 2977 + sec->output_offset; 2978 } 2979 else 2980 { 2981 /* Fill in the entry in the .rela.plt section. */ 2982 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_JUMP_SLOT); 2983 rela.r_addend = 0; 2984 } 2985 2986 loc = relplt->contents + plt_idx * sizeof (ElfNN_External_Rela); 2987 bed->s->swap_reloca_out (output_bfd, &rela, loc); 2988 2989 if (!h->def_regular) 2990 { 2991 /* Mark the symbol as undefined, rather than as defined in 2992 the .plt section. Leave the value alone. */ 2993 sym->st_shndx = SHN_UNDEF; 2994 /* If the symbol is weak, we do need to clear the value. 2995 Otherwise, the PLT entry would provide a definition for 2996 the symbol even if the symbol wasn't defined anywhere, 2997 and so the symbol would never be NULL. */ 2998 if (!h->ref_regular_nonweak) 2999 sym->st_value = 0; 3000 } 3001 } 3002 3003 if (h->got.offset != (bfd_vma) -1 3004 && !(riscv_elf_hash_entry (h)->tls_type & (GOT_TLS_GD | GOT_TLS_IE)) 3005 && !UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)) 3006 { 3007 asection *sgot; 3008 asection *srela; 3009 Elf_Internal_Rela rela; 3010 bool use_elf_append_rela = true; 3011 3012 /* This symbol has an entry in the GOT. Set it up. */ 3013 3014 sgot = htab->elf.sgot; 3015 srela = htab->elf.srelgot; 3016 BFD_ASSERT (sgot != NULL && srela != NULL); 3017 3018 rela.r_offset = sec_addr (sgot) + (h->got.offset &~ (bfd_vma) 1); 3019 3020 /* Handle the ifunc symbol in GOT entry. */ 3021 if (h->def_regular 3022 && h->type == STT_GNU_IFUNC) 3023 { 3024 if (h->plt.offset == (bfd_vma) -1) 3025 { 3026 /* STT_GNU_IFUNC is referenced without PLT. */ 3027 3028 if (htab->elf.splt == NULL) 3029 { 3030 /* Use .rela.iplt section to store .got relocations 3031 in static executable. */ 3032 srela = htab->elf.irelplt; 3033 3034 /* Do not use riscv_elf_append_rela to add dynamic 3035 relocs. */ 3036 use_elf_append_rela = false; 3037 } 3038 3039 if (SYMBOL_REFERENCES_LOCAL (info, h)) 3040 { 3041 info->callbacks->minfo (_("Local IFUNC function `%s' in %pB\n"), 3042 h->root.root.string, 3043 h->root.u.def.section->owner); 3044 3045 rela.r_info = ELFNN_R_INFO (0, R_RISCV_IRELATIVE); 3046 rela.r_addend = (h->root.u.def.value 3047 + h->root.u.def.section->output_section->vma 3048 + h->root.u.def.section->output_offset); 3049 } 3050 else 3051 { 3052 /* Generate R_RISCV_NN. */ 3053 BFD_ASSERT ((h->got.offset & 1) == 0); 3054 BFD_ASSERT (h->dynindx != -1); 3055 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_NN); 3056 rela.r_addend = 0; 3057 } 3058 } 3059 else if (bfd_link_pic (info)) 3060 { 3061 /* Generate R_RISCV_NN. */ 3062 BFD_ASSERT ((h->got.offset & 1) == 0); 3063 BFD_ASSERT (h->dynindx != -1); 3064 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_NN); 3065 rela.r_addend = 0; 3066 } 3067 else 3068 { 3069 asection *plt; 3070 3071 if (!h->pointer_equality_needed) 3072 abort (); 3073 3074 /* For non-shared object, we can't use .got.plt, which 3075 contains the real function address if we need pointer 3076 equality. We load the GOT entry with the PLT entry. */ 3077 plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt; 3078 bfd_put_NN (output_bfd, (plt->output_section->vma 3079 + plt->output_offset 3080 + h->plt.offset), 3081 htab->elf.sgot->contents 3082 + (h->got.offset & ~(bfd_vma) 1)); 3083 return true; 3084 } 3085 } 3086 else if (bfd_link_pic (info) 3087 && SYMBOL_REFERENCES_LOCAL (info, h)) 3088 { 3089 /* If this is a local symbol reference, we just want to emit 3090 a RELATIVE reloc. This can happen if it is a -Bsymbolic link, 3091 or a pie link, or the symbol was forced to be local because 3092 of a version file. The entry in the global offset table will 3093 already have been initialized in the relocate_section function. */ 3094 BFD_ASSERT ((h->got.offset & 1) != 0); 3095 asection *sec = h->root.u.def.section; 3096 rela.r_info = ELFNN_R_INFO (0, R_RISCV_RELATIVE); 3097 rela.r_addend = (h->root.u.def.value 3098 + sec->output_section->vma 3099 + sec->output_offset); 3100 } 3101 else 3102 { 3103 BFD_ASSERT ((h->got.offset & 1) == 0); 3104 BFD_ASSERT (h->dynindx != -1); 3105 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_NN); 3106 rela.r_addend = 0; 3107 } 3108 3109 bfd_put_NN (output_bfd, 0, 3110 sgot->contents + (h->got.offset & ~(bfd_vma) 1)); 3111 3112 if (use_elf_append_rela) 3113 riscv_elf_append_rela (output_bfd, srela, &rela); 3114 else 3115 { 3116 /* Use riscv_elf_append_rela to add the dynamic relocs into 3117 .rela.iplt may cause the overwrite problems. Since we insert 3118 the relocs for PLT didn't handle the reloc_index of .rela.iplt, 3119 but the riscv_elf_append_rela adds the relocs to the place 3120 that are calculated from the reloc_index (in seqential). 3121 3122 One solution is that add these dynamic relocs (GOT IFUNC) 3123 from the last of .rela.iplt section. */ 3124 bfd_vma iplt_idx = htab->last_iplt_index--; 3125 bfd_byte *loc = srela->contents 3126 + iplt_idx * sizeof (ElfNN_External_Rela); 3127 bed->s->swap_reloca_out (output_bfd, &rela, loc); 3128 } 3129 } 3130 3131 if (h->needs_copy) 3132 { 3133 Elf_Internal_Rela rela; 3134 asection *s; 3135 3136 /* This symbols needs a copy reloc. Set it up. */ 3137 BFD_ASSERT (h->dynindx != -1); 3138 3139 rela.r_offset = sec_addr (h->root.u.def.section) + h->root.u.def.value; 3140 rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_COPY); 3141 rela.r_addend = 0; 3142 if (h->root.u.def.section == htab->elf.sdynrelro) 3143 s = htab->elf.sreldynrelro; 3144 else 3145 s = htab->elf.srelbss; 3146 riscv_elf_append_rela (output_bfd, s, &rela); 3147 } 3148 3149 /* Mark some specially defined symbols as absolute. */ 3150 if (h == htab->elf.hdynamic 3151 || (h == htab->elf.hgot || h == htab->elf.hplt)) 3152 sym->st_shndx = SHN_ABS; 3153 3154 return true; 3155 } 3156 3157 /* Finish up local dynamic symbol handling. We set the contents of 3158 various dynamic sections here. */ 3159 3160 static int 3161 riscv_elf_finish_local_dynamic_symbol (void **slot, void *inf) 3162 { 3163 struct elf_link_hash_entry *h = (struct elf_link_hash_entry *) *slot; 3164 struct bfd_link_info *info = (struct bfd_link_info *) inf; 3165 3166 return riscv_elf_finish_dynamic_symbol (info->output_bfd, info, h, NULL); 3167 } 3168 3169 /* Finish up the dynamic sections. */ 3170 3171 static bool 3172 riscv_finish_dyn (bfd *output_bfd, struct bfd_link_info *info, 3173 bfd *dynobj, asection *sdyn) 3174 { 3175 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info); 3176 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd); 3177 size_t dynsize = bed->s->sizeof_dyn; 3178 bfd_byte *dyncon, *dynconend; 3179 3180 dynconend = sdyn->contents + sdyn->size; 3181 for (dyncon = sdyn->contents; dyncon < dynconend; dyncon += dynsize) 3182 { 3183 Elf_Internal_Dyn dyn; 3184 asection *s; 3185 3186 bed->s->swap_dyn_in (dynobj, dyncon, &dyn); 3187 3188 switch (dyn.d_tag) 3189 { 3190 case DT_PLTGOT: 3191 s = htab->elf.sgotplt; 3192 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 3193 break; 3194 case DT_JMPREL: 3195 s = htab->elf.srelplt; 3196 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 3197 break; 3198 case DT_PLTRELSZ: 3199 s = htab->elf.srelplt; 3200 dyn.d_un.d_val = s->size; 3201 break; 3202 default: 3203 continue; 3204 } 3205 3206 bed->s->swap_dyn_out (output_bfd, &dyn, dyncon); 3207 } 3208 return true; 3209 } 3210 3211 static bool 3212 riscv_elf_finish_dynamic_sections (bfd *output_bfd, 3213 struct bfd_link_info *info) 3214 { 3215 bfd *dynobj; 3216 asection *sdyn; 3217 struct riscv_elf_link_hash_table *htab; 3218 3219 htab = riscv_elf_hash_table (info); 3220 BFD_ASSERT (htab != NULL); 3221 dynobj = htab->elf.dynobj; 3222 3223 sdyn = bfd_get_linker_section (dynobj, ".dynamic"); 3224 3225 if (elf_hash_table (info)->dynamic_sections_created) 3226 { 3227 asection *splt; 3228 bool ret; 3229 3230 splt = htab->elf.splt; 3231 BFD_ASSERT (splt != NULL && sdyn != NULL); 3232 3233 ret = riscv_finish_dyn (output_bfd, info, dynobj, sdyn); 3234 3235 if (!ret) 3236 return ret; 3237 3238 /* Fill in the head and tail entries in the procedure linkage table. */ 3239 if (splt->size > 0) 3240 { 3241 int i; 3242 uint32_t plt_header[PLT_HEADER_INSNS]; 3243 ret = riscv_make_plt_header (output_bfd, 3244 sec_addr (htab->elf.sgotplt), 3245 sec_addr (splt), plt_header); 3246 if (!ret) 3247 return ret; 3248 3249 for (i = 0; i < PLT_HEADER_INSNS; i++) 3250 bfd_putl32 (plt_header[i], splt->contents + 4*i); 3251 3252 elf_section_data (splt->output_section)->this_hdr.sh_entsize 3253 = PLT_ENTRY_SIZE; 3254 } 3255 } 3256 3257 if (htab->elf.sgotplt) 3258 { 3259 asection *output_section = htab->elf.sgotplt->output_section; 3260 3261 if (bfd_is_abs_section (output_section)) 3262 { 3263 (*_bfd_error_handler) 3264 (_("discarded output section: `%pA'"), htab->elf.sgotplt); 3265 return false; 3266 } 3267 3268 if (htab->elf.sgotplt->size > 0) 3269 { 3270 /* Write the first two entries in .got.plt, needed for the dynamic 3271 linker. */ 3272 bfd_put_NN (output_bfd, (bfd_vma) -1, htab->elf.sgotplt->contents); 3273 bfd_put_NN (output_bfd, (bfd_vma) 0, 3274 htab->elf.sgotplt->contents + GOT_ENTRY_SIZE); 3275 } 3276 3277 elf_section_data (output_section)->this_hdr.sh_entsize = GOT_ENTRY_SIZE; 3278 } 3279 3280 if (htab->elf.sgot) 3281 { 3282 asection *output_section = htab->elf.sgot->output_section; 3283 3284 if (htab->elf.sgot->size > 0) 3285 { 3286 /* Set the first entry in the global offset table to the address of 3287 the dynamic section. */ 3288 bfd_vma val = sdyn ? sec_addr (sdyn) : 0; 3289 bfd_put_NN (output_bfd, val, htab->elf.sgot->contents); 3290 } 3291 3292 elf_section_data (output_section)->this_hdr.sh_entsize = GOT_ENTRY_SIZE; 3293 } 3294 3295 /* Fill PLT and GOT entries for local STT_GNU_IFUNC symbols. */ 3296 htab_traverse (htab->loc_hash_table, 3297 riscv_elf_finish_local_dynamic_symbol, 3298 info); 3299 3300 return true; 3301 } 3302 3303 /* Return address for Ith PLT stub in section PLT, for relocation REL 3304 or (bfd_vma) -1 if it should not be included. */ 3305 3306 static bfd_vma 3307 riscv_elf_plt_sym_val (bfd_vma i, const asection *plt, 3308 const arelent *rel ATTRIBUTE_UNUSED) 3309 { 3310 return plt->vma + PLT_HEADER_SIZE + i * PLT_ENTRY_SIZE; 3311 } 3312 3313 static enum elf_reloc_type_class 3314 riscv_reloc_type_class (const struct bfd_link_info *info ATTRIBUTE_UNUSED, 3315 const asection *rel_sec ATTRIBUTE_UNUSED, 3316 const Elf_Internal_Rela *rela) 3317 { 3318 switch (ELFNN_R_TYPE (rela->r_info)) 3319 { 3320 case R_RISCV_RELATIVE: 3321 return reloc_class_relative; 3322 case R_RISCV_JUMP_SLOT: 3323 return reloc_class_plt; 3324 case R_RISCV_COPY: 3325 return reloc_class_copy; 3326 default: 3327 return reloc_class_normal; 3328 } 3329 } 3330 3331 /* Given the ELF header flags in FLAGS, it returns a string that describes the 3332 float ABI. */ 3333 3334 static const char * 3335 riscv_float_abi_string (flagword flags) 3336 { 3337 switch (flags & EF_RISCV_FLOAT_ABI) 3338 { 3339 case EF_RISCV_FLOAT_ABI_SOFT: 3340 return "soft-float"; 3341 break; 3342 case EF_RISCV_FLOAT_ABI_SINGLE: 3343 return "single-float"; 3344 break; 3345 case EF_RISCV_FLOAT_ABI_DOUBLE: 3346 return "double-float"; 3347 break; 3348 case EF_RISCV_FLOAT_ABI_QUAD: 3349 return "quad-float"; 3350 break; 3351 default: 3352 abort (); 3353 } 3354 } 3355 3356 /* The information of architecture elf attributes. */ 3357 static riscv_subset_list_t in_subsets; 3358 static riscv_subset_list_t out_subsets; 3359 static riscv_subset_list_t merged_subsets; 3360 3361 /* Predicator for standard extension. */ 3362 3363 static bool 3364 riscv_std_ext_p (const char *name) 3365 { 3366 return (strlen (name) == 1) && (name[0] != 'x') && (name[0] != 's'); 3367 } 3368 3369 /* Update the output subset's version to match the input when the input 3370 subset's version is newer. */ 3371 3372 static void 3373 riscv_update_subset_version (struct riscv_subset_t *in, 3374 struct riscv_subset_t *out) 3375 { 3376 if (in == NULL || out == NULL) 3377 return; 3378 3379 /* Update the output ISA versions to the newest ones, but otherwise don't 3380 provide any errors or warnings about mis-matched ISA versions as it's 3381 generally too tricky to check for these at link time. */ 3382 if ((in->major_version > out->major_version) 3383 || (in->major_version == out->major_version 3384 && in->minor_version > out->minor_version) 3385 || (out->major_version == RISCV_UNKNOWN_VERSION)) 3386 { 3387 out->major_version = in->major_version; 3388 out->minor_version = in->minor_version; 3389 } 3390 } 3391 3392 /* Return true if subset is 'i' or 'e'. */ 3393 3394 static bool 3395 riscv_i_or_e_p (bfd *ibfd, 3396 const char *arch, 3397 struct riscv_subset_t *subset) 3398 { 3399 if ((strcasecmp (subset->name, "e") != 0) 3400 && (strcasecmp (subset->name, "i") != 0)) 3401 { 3402 _bfd_error_handler 3403 (_("error: %pB: corrupted ISA string '%s'. " 3404 "First letter should be 'i' or 'e' but got '%s'"), 3405 ibfd, arch, subset->name); 3406 return false; 3407 } 3408 return true; 3409 } 3410 3411 /* Merge standard extensions. 3412 3413 Return Value: 3414 Return FALSE if failed to merge. 3415 3416 Arguments: 3417 `bfd`: bfd handler. 3418 `in_arch`: Raw ISA string for input object. 3419 `out_arch`: Raw ISA string for output object. 3420 `pin`: Subset list for input object. 3421 `pout`: Subset list for output object. */ 3422 3423 static bool 3424 riscv_merge_std_ext (bfd *ibfd, 3425 const char *in_arch, 3426 const char *out_arch, 3427 struct riscv_subset_t **pin, 3428 struct riscv_subset_t **pout) 3429 { 3430 const char *standard_exts = "mafdqlcbjtpvnh"; 3431 const char *p; 3432 struct riscv_subset_t *in = *pin; 3433 struct riscv_subset_t *out = *pout; 3434 3435 /* First letter should be 'i' or 'e'. */ 3436 if (!riscv_i_or_e_p (ibfd, in_arch, in)) 3437 return false; 3438 3439 if (!riscv_i_or_e_p (ibfd, out_arch, out)) 3440 return false; 3441 3442 if (strcasecmp (in->name, out->name) != 0) 3443 { 3444 /* TODO: We might allow merge 'i' with 'e'. */ 3445 _bfd_error_handler 3446 (_("error: %pB: mis-matched ISA string to merge '%s' and '%s'"), 3447 ibfd, in->name, out->name); 3448 return false; 3449 } 3450 3451 riscv_update_subset_version(in, out); 3452 riscv_add_subset (&merged_subsets, 3453 out->name, out->major_version, out->minor_version); 3454 3455 in = in->next; 3456 out = out->next; 3457 3458 /* Handle standard extension first. */ 3459 for (p = standard_exts; *p; ++p) 3460 { 3461 struct riscv_subset_t *ext_in, *ext_out, *ext_merged; 3462 char find_ext[2] = {*p, '\0'}; 3463 bool find_in, find_out; 3464 3465 find_in = riscv_lookup_subset (&in_subsets, find_ext, &ext_in); 3466 find_out = riscv_lookup_subset (&out_subsets, find_ext, &ext_out); 3467 3468 if (!find_in && !find_out) 3469 continue; 3470 3471 if (find_in && find_out) 3472 riscv_update_subset_version(ext_in, ext_out); 3473 3474 ext_merged = find_out ? ext_out : ext_in; 3475 riscv_add_subset (&merged_subsets, ext_merged->name, 3476 ext_merged->major_version, ext_merged->minor_version); 3477 } 3478 3479 /* Skip all standard extensions. */ 3480 while ((in != NULL) && riscv_std_ext_p (in->name)) in = in->next; 3481 while ((out != NULL) && riscv_std_ext_p (out->name)) out = out->next; 3482 3483 *pin = in; 3484 *pout = out; 3485 3486 return true; 3487 } 3488 3489 /* Merge multi letter extensions. PIN is a pointer to the head of the input 3490 object subset list. Likewise for POUT and the output object. Return TRUE 3491 on success and FALSE when a conflict is found. */ 3492 3493 static bool 3494 riscv_merge_multi_letter_ext (riscv_subset_t **pin, 3495 riscv_subset_t **pout) 3496 { 3497 riscv_subset_t *in = *pin; 3498 riscv_subset_t *out = *pout; 3499 riscv_subset_t *tail; 3500 3501 int cmp; 3502 3503 while (in && out) 3504 { 3505 cmp = riscv_compare_subsets (in->name, out->name); 3506 3507 if (cmp < 0) 3508 { 3509 /* `in' comes before `out', append `in' and increment. */ 3510 riscv_add_subset (&merged_subsets, in->name, in->major_version, 3511 in->minor_version); 3512 in = in->next; 3513 } 3514 else if (cmp > 0) 3515 { 3516 /* `out' comes before `in', append `out' and increment. */ 3517 riscv_add_subset (&merged_subsets, out->name, out->major_version, 3518 out->minor_version); 3519 out = out->next; 3520 } 3521 else 3522 { 3523 /* Both present, check version and increment both. */ 3524 riscv_update_subset_version (in, out); 3525 3526 riscv_add_subset (&merged_subsets, out->name, out->major_version, 3527 out->minor_version); 3528 out = out->next; 3529 in = in->next; 3530 } 3531 } 3532 3533 if (in || out) 3534 { 3535 /* If we're here, either `in' or `out' is running longer than 3536 the other. So, we need to append the corresponding tail. */ 3537 tail = in ? in : out; 3538 while (tail) 3539 { 3540 riscv_add_subset (&merged_subsets, tail->name, tail->major_version, 3541 tail->minor_version); 3542 tail = tail->next; 3543 } 3544 } 3545 3546 return true; 3547 } 3548 3549 /* Merge Tag_RISCV_arch attribute. */ 3550 3551 static char * 3552 riscv_merge_arch_attr_info (bfd *ibfd, char *in_arch, char *out_arch) 3553 { 3554 riscv_subset_t *in, *out; 3555 char *merged_arch_str; 3556 3557 unsigned xlen_in, xlen_out; 3558 merged_subsets.head = NULL; 3559 merged_subsets.tail = NULL; 3560 3561 riscv_parse_subset_t riscv_rps_ld_in = 3562 {&in_subsets, _bfd_error_handler, &xlen_in, NULL, false}; 3563 riscv_parse_subset_t riscv_rps_ld_out = 3564 {&out_subsets, _bfd_error_handler, &xlen_out, NULL, false}; 3565 3566 if (in_arch == NULL && out_arch == NULL) 3567 return NULL; 3568 if (in_arch == NULL && out_arch != NULL) 3569 return out_arch; 3570 if (in_arch != NULL && out_arch == NULL) 3571 return in_arch; 3572 3573 /* Parse subset from ISA string. */ 3574 if (!riscv_parse_subset (&riscv_rps_ld_in, in_arch)) 3575 return NULL; 3576 if (!riscv_parse_subset (&riscv_rps_ld_out, out_arch)) 3577 return NULL; 3578 3579 /* Checking XLEN. */ 3580 if (xlen_out != xlen_in) 3581 { 3582 _bfd_error_handler 3583 (_("error: %pB: ISA string of input (%s) doesn't match " 3584 "output (%s)"), ibfd, in_arch, out_arch); 3585 return NULL; 3586 } 3587 3588 /* Merge subset list. */ 3589 in = in_subsets.head; 3590 out = out_subsets.head; 3591 3592 /* Merge standard extension. */ 3593 if (!riscv_merge_std_ext (ibfd, in_arch, out_arch, &in, &out)) 3594 return NULL; 3595 3596 /* Merge all non-single letter extensions with single call. */ 3597 if (!riscv_merge_multi_letter_ext (&in, &out)) 3598 return NULL; 3599 3600 if (xlen_in != xlen_out) 3601 { 3602 _bfd_error_handler 3603 (_("error: %pB: XLEN of input (%u) doesn't match " 3604 "output (%u)"), ibfd, xlen_in, xlen_out); 3605 return NULL; 3606 } 3607 3608 if (xlen_in != ARCH_SIZE) 3609 { 3610 _bfd_error_handler 3611 (_("error: %pB: unsupported XLEN (%u), you might be " 3612 "using wrong emulation"), ibfd, xlen_in); 3613 return NULL; 3614 } 3615 3616 merged_arch_str = riscv_arch_str (ARCH_SIZE, &merged_subsets); 3617 3618 /* Release the subset lists. */ 3619 riscv_release_subset_list (&in_subsets); 3620 riscv_release_subset_list (&out_subsets); 3621 riscv_release_subset_list (&merged_subsets); 3622 3623 return merged_arch_str; 3624 } 3625 3626 /* Merge object attributes from IBFD into output_bfd of INFO. 3627 Raise an error if there are conflicting attributes. */ 3628 3629 static bool 3630 riscv_merge_attributes (bfd *ibfd, struct bfd_link_info *info) 3631 { 3632 bfd *obfd = info->output_bfd; 3633 obj_attribute *in_attr; 3634 obj_attribute *out_attr; 3635 bool result = true; 3636 bool priv_attrs_merged = false; 3637 const char *sec_name = get_elf_backend_data (ibfd)->obj_attrs_section; 3638 unsigned int i; 3639 3640 /* Skip linker created files. */ 3641 if (ibfd->flags & BFD_LINKER_CREATED) 3642 return true; 3643 3644 /* Skip any input that doesn't have an attribute section. 3645 This enables to link object files without attribute section with 3646 any others. */ 3647 if (bfd_get_section_by_name (ibfd, sec_name) == NULL) 3648 return true; 3649 3650 if (!elf_known_obj_attributes_proc (obfd)[0].i) 3651 { 3652 /* This is the first object. Copy the attributes. */ 3653 _bfd_elf_copy_obj_attributes (ibfd, obfd); 3654 3655 out_attr = elf_known_obj_attributes_proc (obfd); 3656 3657 /* Use the Tag_null value to indicate the attributes have been 3658 initialized. */ 3659 out_attr[0].i = 1; 3660 3661 return true; 3662 } 3663 3664 in_attr = elf_known_obj_attributes_proc (ibfd); 3665 out_attr = elf_known_obj_attributes_proc (obfd); 3666 3667 for (i = LEAST_KNOWN_OBJ_ATTRIBUTE; i < NUM_KNOWN_OBJ_ATTRIBUTES; i++) 3668 { 3669 switch (i) 3670 { 3671 case Tag_RISCV_arch: 3672 if (!out_attr[Tag_RISCV_arch].s) 3673 out_attr[Tag_RISCV_arch].s = in_attr[Tag_RISCV_arch].s; 3674 else if (in_attr[Tag_RISCV_arch].s 3675 && out_attr[Tag_RISCV_arch].s) 3676 { 3677 /* Check compatible. */ 3678 char *merged_arch = 3679 riscv_merge_arch_attr_info (ibfd, 3680 in_attr[Tag_RISCV_arch].s, 3681 out_attr[Tag_RISCV_arch].s); 3682 if (merged_arch == NULL) 3683 { 3684 result = false; 3685 out_attr[Tag_RISCV_arch].s = ""; 3686 } 3687 else 3688 out_attr[Tag_RISCV_arch].s = merged_arch; 3689 } 3690 break; 3691 3692 case Tag_RISCV_priv_spec: 3693 case Tag_RISCV_priv_spec_minor: 3694 case Tag_RISCV_priv_spec_revision: 3695 /* If we have handled the privileged elf attributes, then skip it. */ 3696 if (!priv_attrs_merged) 3697 { 3698 unsigned int Tag_a = Tag_RISCV_priv_spec; 3699 unsigned int Tag_b = Tag_RISCV_priv_spec_minor; 3700 unsigned int Tag_c = Tag_RISCV_priv_spec_revision; 3701 enum riscv_spec_class in_priv_spec = PRIV_SPEC_CLASS_NONE; 3702 enum riscv_spec_class out_priv_spec = PRIV_SPEC_CLASS_NONE; 3703 3704 /* Get the privileged spec class from elf attributes. */ 3705 riscv_get_priv_spec_class_from_numbers (in_attr[Tag_a].i, 3706 in_attr[Tag_b].i, 3707 in_attr[Tag_c].i, 3708 &in_priv_spec); 3709 riscv_get_priv_spec_class_from_numbers (out_attr[Tag_a].i, 3710 out_attr[Tag_b].i, 3711 out_attr[Tag_c].i, 3712 &out_priv_spec); 3713 3714 /* Allow to link the object without the privileged specs. */ 3715 if (out_priv_spec == PRIV_SPEC_CLASS_NONE) 3716 { 3717 out_attr[Tag_a].i = in_attr[Tag_a].i; 3718 out_attr[Tag_b].i = in_attr[Tag_b].i; 3719 out_attr[Tag_c].i = in_attr[Tag_c].i; 3720 } 3721 else if (in_priv_spec != PRIV_SPEC_CLASS_NONE 3722 && in_priv_spec != out_priv_spec) 3723 { 3724 _bfd_error_handler 3725 (_("warning: %pB use privileged spec version %u.%u.%u but " 3726 "the output use version %u.%u.%u"), 3727 ibfd, 3728 in_attr[Tag_a].i, 3729 in_attr[Tag_b].i, 3730 in_attr[Tag_c].i, 3731 out_attr[Tag_a].i, 3732 out_attr[Tag_b].i, 3733 out_attr[Tag_c].i); 3734 3735 /* The privileged spec v1.9.1 can not be linked with others 3736 since the conflicts, so we plan to drop it in a year or 3737 two. */ 3738 if (in_priv_spec == PRIV_SPEC_CLASS_1P9P1 3739 || out_priv_spec == PRIV_SPEC_CLASS_1P9P1) 3740 { 3741 _bfd_error_handler 3742 (_("warning: privileged spec version 1.9.1 can not be " 3743 "linked with other spec versions")); 3744 } 3745 3746 /* Update the output privileged spec to the newest one. */ 3747 if (in_priv_spec > out_priv_spec) 3748 { 3749 out_attr[Tag_a].i = in_attr[Tag_a].i; 3750 out_attr[Tag_b].i = in_attr[Tag_b].i; 3751 out_attr[Tag_c].i = in_attr[Tag_c].i; 3752 } 3753 } 3754 priv_attrs_merged = true; 3755 } 3756 break; 3757 3758 case Tag_RISCV_unaligned_access: 3759 out_attr[i].i |= in_attr[i].i; 3760 break; 3761 3762 case Tag_RISCV_stack_align: 3763 if (out_attr[i].i == 0) 3764 out_attr[i].i = in_attr[i].i; 3765 else if (in_attr[i].i != 0 3766 && out_attr[i].i != 0 3767 && out_attr[i].i != in_attr[i].i) 3768 { 3769 _bfd_error_handler 3770 (_("error: %pB use %u-byte stack aligned but the output " 3771 "use %u-byte stack aligned"), 3772 ibfd, in_attr[i].i, out_attr[i].i); 3773 result = false; 3774 } 3775 break; 3776 3777 default: 3778 result &= _bfd_elf_merge_unknown_attribute_low (ibfd, obfd, i); 3779 } 3780 3781 /* If out_attr was copied from in_attr then it won't have a type yet. */ 3782 if (in_attr[i].type && !out_attr[i].type) 3783 out_attr[i].type = in_attr[i].type; 3784 } 3785 3786 /* Merge Tag_compatibility attributes and any common GNU ones. */ 3787 if (!_bfd_elf_merge_object_attributes (ibfd, info)) 3788 return false; 3789 3790 /* Check for any attributes not known on RISC-V. */ 3791 result &= _bfd_elf_merge_unknown_attribute_list (ibfd, obfd); 3792 3793 return result; 3794 } 3795 3796 /* Merge backend specific data from an object file to the output 3797 object file when linking. */ 3798 3799 static bool 3800 _bfd_riscv_elf_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info) 3801 { 3802 bfd *obfd = info->output_bfd; 3803 flagword new_flags, old_flags; 3804 3805 if (!is_riscv_elf (ibfd) || !is_riscv_elf (obfd)) 3806 return true; 3807 3808 if (strcmp (bfd_get_target (ibfd), bfd_get_target (obfd)) != 0) 3809 { 3810 (*_bfd_error_handler) 3811 (_("%pB: ABI is incompatible with that of the selected emulation:\n" 3812 " target emulation `%s' does not match `%s'"), 3813 ibfd, bfd_get_target (ibfd), bfd_get_target (obfd)); 3814 return false; 3815 } 3816 3817 if (!_bfd_elf_merge_object_attributes (ibfd, info)) 3818 return false; 3819 3820 if (!riscv_merge_attributes (ibfd, info)) 3821 return false; 3822 3823 /* Check to see if the input BFD actually contains any sections. If not, 3824 its flags may not have been initialized either, but it cannot actually 3825 cause any incompatibility. Do not short-circuit dynamic objects; their 3826 section list may be emptied by elf_link_add_object_symbols. 3827 3828 Also check to see if there are no code sections in the input. In this 3829 case, there is no need to check for code specific flags. */ 3830 if (!(ibfd->flags & DYNAMIC)) 3831 { 3832 bool null_input_bfd = true; 3833 bool only_data_sections = true; 3834 asection *sec; 3835 3836 for (sec = ibfd->sections; sec != NULL; sec = sec->next) 3837 { 3838 null_input_bfd = false; 3839 3840 if ((bfd_section_flags (sec) 3841 & (SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS)) 3842 == (SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS)) 3843 { 3844 only_data_sections = false; 3845 break; 3846 } 3847 } 3848 3849 if (null_input_bfd || only_data_sections) 3850 return true; 3851 } 3852 3853 new_flags = elf_elfheader (ibfd)->e_flags; 3854 old_flags = elf_elfheader (obfd)->e_flags; 3855 3856 if (!elf_flags_init (obfd)) 3857 { 3858 elf_flags_init (obfd) = true; 3859 elf_elfheader (obfd)->e_flags = new_flags; 3860 return true; 3861 } 3862 3863 /* Disallow linking different float ABIs. */ 3864 if ((old_flags ^ new_flags) & EF_RISCV_FLOAT_ABI) 3865 { 3866 (*_bfd_error_handler) 3867 (_("%pB: can't link %s modules with %s modules"), ibfd, 3868 riscv_float_abi_string (new_flags), 3869 riscv_float_abi_string (old_flags)); 3870 goto fail; 3871 } 3872 3873 /* Disallow linking RVE and non-RVE. */ 3874 if ((old_flags ^ new_flags) & EF_RISCV_RVE) 3875 { 3876 (*_bfd_error_handler) 3877 (_("%pB: can't link RVE with other target"), ibfd); 3878 goto fail; 3879 } 3880 3881 /* Allow linking RVC and non-RVC, and keep the RVC flag. */ 3882 elf_elfheader (obfd)->e_flags |= new_flags & EF_RISCV_RVC; 3883 3884 /* Allow linking TSO and non-TSO, and keep the TSO flag. */ 3885 elf_elfheader (obfd)->e_flags |= new_flags & EF_RISCV_TSO; 3886 3887 return true; 3888 3889 fail: 3890 bfd_set_error (bfd_error_bad_value); 3891 return false; 3892 } 3893 3894 /* A second format for recording PC-relative hi relocations. This stores the 3895 information required to relax them to GP-relative addresses. */ 3896 3897 typedef struct riscv_pcgp_hi_reloc riscv_pcgp_hi_reloc; 3898 struct riscv_pcgp_hi_reloc 3899 { 3900 bfd_vma hi_sec_off; 3901 bfd_vma hi_addend; 3902 bfd_vma hi_addr; 3903 unsigned hi_sym; 3904 asection *sym_sec; 3905 bool undefined_weak; 3906 riscv_pcgp_hi_reloc *next; 3907 }; 3908 3909 typedef struct riscv_pcgp_lo_reloc riscv_pcgp_lo_reloc; 3910 struct riscv_pcgp_lo_reloc 3911 { 3912 bfd_vma hi_sec_off; 3913 riscv_pcgp_lo_reloc *next; 3914 }; 3915 3916 typedef struct 3917 { 3918 riscv_pcgp_hi_reloc *hi; 3919 riscv_pcgp_lo_reloc *lo; 3920 } riscv_pcgp_relocs; 3921 3922 /* Initialize the pcgp reloc info in P. */ 3923 3924 static bool 3925 riscv_init_pcgp_relocs (riscv_pcgp_relocs *p) 3926 { 3927 p->hi = NULL; 3928 p->lo = NULL; 3929 return true; 3930 } 3931 3932 /* Free the pcgp reloc info in P. */ 3933 3934 static void 3935 riscv_free_pcgp_relocs (riscv_pcgp_relocs *p, 3936 bfd *abfd ATTRIBUTE_UNUSED, 3937 asection *sec ATTRIBUTE_UNUSED) 3938 { 3939 riscv_pcgp_hi_reloc *c; 3940 riscv_pcgp_lo_reloc *l; 3941 3942 for (c = p->hi; c != NULL; ) 3943 { 3944 riscv_pcgp_hi_reloc *next = c->next; 3945 free (c); 3946 c = next; 3947 } 3948 3949 for (l = p->lo; l != NULL; ) 3950 { 3951 riscv_pcgp_lo_reloc *next = l->next; 3952 free (l); 3953 l = next; 3954 } 3955 } 3956 3957 /* Record pcgp hi part reloc info in P, using HI_SEC_OFF as the lookup index. 3958 The HI_ADDEND, HI_ADDR, HI_SYM, and SYM_SEC args contain info required to 3959 relax the corresponding lo part reloc. */ 3960 3961 static bool 3962 riscv_record_pcgp_hi_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off, 3963 bfd_vma hi_addend, bfd_vma hi_addr, 3964 unsigned hi_sym, asection *sym_sec, 3965 bool undefined_weak) 3966 { 3967 riscv_pcgp_hi_reloc *new = bfd_malloc (sizeof (*new)); 3968 if (!new) 3969 return false; 3970 new->hi_sec_off = hi_sec_off; 3971 new->hi_addend = hi_addend; 3972 new->hi_addr = hi_addr; 3973 new->hi_sym = hi_sym; 3974 new->sym_sec = sym_sec; 3975 new->undefined_weak = undefined_weak; 3976 new->next = p->hi; 3977 p->hi = new; 3978 return true; 3979 } 3980 3981 /* Look up hi part pcgp reloc info in P, using HI_SEC_OFF as the lookup index. 3982 This is used by a lo part reloc to find the corresponding hi part reloc. */ 3983 3984 static riscv_pcgp_hi_reloc * 3985 riscv_find_pcgp_hi_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off) 3986 { 3987 riscv_pcgp_hi_reloc *c; 3988 3989 for (c = p->hi; c != NULL; c = c->next) 3990 if (c->hi_sec_off == hi_sec_off) 3991 return c; 3992 return NULL; 3993 } 3994 3995 /* Record pcgp lo part reloc info in P, using HI_SEC_OFF as the lookup info. 3996 This is used to record relocs that can't be relaxed. */ 3997 3998 static bool 3999 riscv_record_pcgp_lo_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off) 4000 { 4001 riscv_pcgp_lo_reloc *new = bfd_malloc (sizeof (*new)); 4002 if (!new) 4003 return false; 4004 new->hi_sec_off = hi_sec_off; 4005 new->next = p->lo; 4006 p->lo = new; 4007 return true; 4008 } 4009 4010 /* Look up lo part pcgp reloc info in P, using HI_SEC_OFF as the lookup index. 4011 This is used by a hi part reloc to find the corresponding lo part reloc. */ 4012 4013 static bool 4014 riscv_find_pcgp_lo_reloc (riscv_pcgp_relocs *p, bfd_vma hi_sec_off) 4015 { 4016 riscv_pcgp_lo_reloc *c; 4017 4018 for (c = p->lo; c != NULL; c = c->next) 4019 if (c->hi_sec_off == hi_sec_off) 4020 return true; 4021 return false; 4022 } 4023 4024 static void 4025 riscv_update_pcgp_relocs (riscv_pcgp_relocs *p, asection *deleted_sec, 4026 bfd_vma deleted_addr, size_t deleted_count) 4027 { 4028 /* Bytes have already been deleted and toaddr should match the old section 4029 size for our checks, so adjust it here. */ 4030 bfd_vma toaddr = deleted_sec->size + deleted_count; 4031 riscv_pcgp_lo_reloc *l; 4032 riscv_pcgp_hi_reloc *h; 4033 4034 /* Update section offsets of corresponding pcrel_hi relocs for the pcrel_lo 4035 entries where they occur after the deleted bytes. */ 4036 for (l = p->lo; l != NULL; l = l->next) 4037 if (l->hi_sec_off > deleted_addr 4038 && l->hi_sec_off < toaddr) 4039 l->hi_sec_off -= deleted_count; 4040 4041 /* Update both section offsets, and symbol values of pcrel_hi relocs where 4042 these values occur after the deleted bytes. */ 4043 for (h = p->hi; h != NULL; h = h->next) 4044 { 4045 if (h->hi_sec_off > deleted_addr 4046 && h->hi_sec_off < toaddr) 4047 h->hi_sec_off -= deleted_count; 4048 if (h->sym_sec == deleted_sec 4049 && h->hi_addr > deleted_addr 4050 && h->hi_addr < toaddr) 4051 h->hi_addr -= deleted_count; 4052 } 4053 } 4054 4055 /* Delete some bytes, adjust relcocations and symbol table from a section. */ 4056 4057 static bool 4058 _riscv_relax_delete_bytes (bfd *abfd, 4059 asection *sec, 4060 bfd_vma addr, 4061 size_t count, 4062 struct bfd_link_info *link_info, 4063 riscv_pcgp_relocs *p, 4064 bfd_vma delete_total, 4065 bfd_vma toaddr) 4066 { 4067 unsigned int i, symcount; 4068 struct elf_link_hash_entry **sym_hashes = elf_sym_hashes (abfd); 4069 Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 4070 unsigned int sec_shndx = _bfd_elf_section_from_bfd_section (abfd, sec); 4071 struct bfd_elf_section_data *data = elf_section_data (sec); 4072 bfd_byte *contents = data->this_hdr.contents; 4073 size_t bytes_to_move = toaddr - addr - count; 4074 4075 /* Actually delete the bytes. */ 4076 sec->size -= count; 4077 memmove (contents + addr, contents + addr + count + delete_total, bytes_to_move); 4078 4079 /* Still adjust relocations and symbols in non-linear times. */ 4080 toaddr = sec->size + count; 4081 4082 /* Adjust the location of all of the relocs. Note that we need not 4083 adjust the addends, since all PC-relative references must be against 4084 symbols, which we will adjust below. */ 4085 for (i = 0; i < sec->reloc_count; i++) 4086 if (data->relocs[i].r_offset > addr && data->relocs[i].r_offset < toaddr) 4087 data->relocs[i].r_offset -= count; 4088 4089 /* Adjust the hi_sec_off, and the hi_addr of any entries in the pcgp relocs 4090 table for which these values occur after the deleted bytes. */ 4091 if (p) 4092 riscv_update_pcgp_relocs (p, sec, addr, count); 4093 4094 /* Adjust the local symbols defined in this section. */ 4095 for (i = 0; i < symtab_hdr->sh_info; i++) 4096 { 4097 Elf_Internal_Sym *sym = (Elf_Internal_Sym *) symtab_hdr->contents + i; 4098 if (sym->st_shndx == sec_shndx) 4099 { 4100 /* If the symbol is in the range of memory we just moved, we 4101 have to adjust its value. */ 4102 if (sym->st_value > addr && sym->st_value <= toaddr) 4103 sym->st_value -= count; 4104 4105 /* If the symbol *spans* the bytes we just deleted (i.e. its 4106 *end* is in the moved bytes but its *start* isn't), then we 4107 must adjust its size. 4108 4109 This test needs to use the original value of st_value, otherwise 4110 we might accidentally decrease size when deleting bytes right 4111 before the symbol. But since deleted relocs can't span across 4112 symbols, we can't have both a st_value and a st_size decrease, 4113 so it is simpler to just use an else. */ 4114 else if (sym->st_value <= addr 4115 && sym->st_value + sym->st_size > addr 4116 && sym->st_value + sym->st_size <= toaddr) 4117 sym->st_size -= count; 4118 } 4119 } 4120 4121 /* Now adjust the global symbols defined in this section. */ 4122 symcount = ((symtab_hdr->sh_size / sizeof (ElfNN_External_Sym)) 4123 - symtab_hdr->sh_info); 4124 4125 for (i = 0; i < symcount; i++) 4126 { 4127 struct elf_link_hash_entry *sym_hash = sym_hashes[i]; 4128 4129 /* The '--wrap SYMBOL' option is causing a pain when the object file, 4130 containing the definition of __wrap_SYMBOL, includes a direct 4131 call to SYMBOL as well. Since both __wrap_SYMBOL and SYMBOL reference 4132 the same symbol (which is __wrap_SYMBOL), but still exist as two 4133 different symbols in 'sym_hashes', we don't want to adjust 4134 the global symbol __wrap_SYMBOL twice. 4135 4136 The same problem occurs with symbols that are versioned_hidden, as 4137 foo becomes an alias for foo@BAR, and hence they need the same 4138 treatment. */ 4139 if (link_info->wrap_hash != NULL 4140 || sym_hash->versioned != unversioned) 4141 { 4142 struct elf_link_hash_entry **cur_sym_hashes; 4143 4144 /* Loop only over the symbols which have already been checked. */ 4145 for (cur_sym_hashes = sym_hashes; cur_sym_hashes < &sym_hashes[i]; 4146 cur_sym_hashes++) 4147 { 4148 /* If the current symbol is identical to 'sym_hash', that means 4149 the symbol was already adjusted (or at least checked). */ 4150 if (*cur_sym_hashes == sym_hash) 4151 break; 4152 } 4153 /* Don't adjust the symbol again. */ 4154 if (cur_sym_hashes < &sym_hashes[i]) 4155 continue; 4156 } 4157 4158 if ((sym_hash->root.type == bfd_link_hash_defined 4159 || sym_hash->root.type == bfd_link_hash_defweak) 4160 && sym_hash->root.u.def.section == sec) 4161 { 4162 /* As above, adjust the value if needed. */ 4163 if (sym_hash->root.u.def.value > addr 4164 && sym_hash->root.u.def.value <= toaddr) 4165 sym_hash->root.u.def.value -= count; 4166 4167 /* As above, adjust the size if needed. */ 4168 else if (sym_hash->root.u.def.value <= addr 4169 && sym_hash->root.u.def.value + sym_hash->size > addr 4170 && sym_hash->root.u.def.value + sym_hash->size <= toaddr) 4171 sym_hash->size -= count; 4172 } 4173 } 4174 4175 return true; 4176 } 4177 4178 typedef bool (*relax_delete_t) (bfd *, asection *, 4179 bfd_vma, size_t, 4180 struct bfd_link_info *, 4181 riscv_pcgp_relocs *, 4182 Elf_Internal_Rela *); 4183 4184 static relax_delete_t riscv_relax_delete_bytes; 4185 4186 /* Do not delete some bytes from a section while relaxing. 4187 Just mark the deleted bytes as R_RISCV_DELETE. */ 4188 4189 static bool 4190 _riscv_relax_delete_piecewise (bfd *abfd ATTRIBUTE_UNUSED, 4191 asection *sec ATTRIBUTE_UNUSED, 4192 bfd_vma addr, 4193 size_t count, 4194 struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 4195 riscv_pcgp_relocs *p ATTRIBUTE_UNUSED, 4196 Elf_Internal_Rela *rel) 4197 { 4198 if (rel == NULL) 4199 return false; 4200 rel->r_info = ELFNN_R_INFO (0, R_RISCV_DELETE); 4201 rel->r_offset = addr; 4202 rel->r_addend = count; 4203 return true; 4204 } 4205 4206 /* Delete some bytes from a section while relaxing. */ 4207 4208 static bool 4209 _riscv_relax_delete_immediate (bfd *abfd, 4210 asection *sec, 4211 bfd_vma addr, 4212 size_t count, 4213 struct bfd_link_info *link_info, 4214 riscv_pcgp_relocs *p, 4215 Elf_Internal_Rela *rel) 4216 { 4217 if (rel != NULL) 4218 rel->r_info = ELFNN_R_INFO (0, R_RISCV_NONE); 4219 return _riscv_relax_delete_bytes (abfd, sec, addr, count, 4220 link_info, p, 0, sec->size); 4221 } 4222 4223 /* Delete the bytes for R_RISCV_DELETE relocs. */ 4224 4225 static bool 4226 riscv_relax_resolve_delete_relocs (bfd *abfd, 4227 asection *sec, 4228 struct bfd_link_info *link_info, 4229 Elf_Internal_Rela *relocs) 4230 { 4231 bfd_vma delete_total = 0; 4232 unsigned int i; 4233 4234 for (i = 0; i < sec->reloc_count; i++) 4235 { 4236 Elf_Internal_Rela *rel = relocs + i; 4237 if (ELFNN_R_TYPE (rel->r_info) != R_RISCV_DELETE) 4238 continue; 4239 4240 /* Find the next R_RISCV_DELETE reloc if possible. */ 4241 Elf_Internal_Rela *rel_next = NULL; 4242 unsigned int start = rel - relocs; 4243 for (i = start; i < sec->reloc_count; i++) 4244 { 4245 /* Since we only replace existing relocs and don't add new relocs, the 4246 relocs are in sequential order. We can skip the relocs prior to this 4247 one, making this search linear time. */ 4248 rel_next = relocs + i; 4249 if (ELFNN_R_TYPE ((rel_next)->r_info) == R_RISCV_DELETE 4250 && (rel_next)->r_offset > rel->r_offset) 4251 { 4252 BFD_ASSERT (rel_next - rel > 0); 4253 break; 4254 } 4255 else 4256 rel_next = NULL; 4257 } 4258 4259 bfd_vma toaddr = rel_next == NULL ? sec->size : rel_next->r_offset; 4260 if (!_riscv_relax_delete_bytes (abfd, sec, rel->r_offset, rel->r_addend, 4261 link_info, NULL, delete_total, toaddr)) 4262 return false; 4263 4264 delete_total += rel->r_addend; 4265 rel->r_info = ELFNN_R_INFO (0, R_RISCV_NONE); 4266 4267 /* Skip ahead to the next delete reloc. */ 4268 i = rel_next != NULL ? (unsigned int) (rel_next - relocs - 1) 4269 : sec->reloc_count; 4270 } 4271 4272 return true; 4273 } 4274 4275 typedef bool (*relax_func_t) (bfd *, asection *, asection *, 4276 struct bfd_link_info *, 4277 Elf_Internal_Rela *, 4278 bfd_vma, bfd_vma, bfd_vma, bool *, 4279 riscv_pcgp_relocs *, 4280 bool undefined_weak); 4281 4282 /* Relax AUIPC + JALR into JAL. */ 4283 4284 static bool 4285 _bfd_riscv_relax_call (bfd *abfd, asection *sec, asection *sym_sec, 4286 struct bfd_link_info *link_info, 4287 Elf_Internal_Rela *rel, 4288 bfd_vma symval, 4289 bfd_vma max_alignment, 4290 bfd_vma reserve_size ATTRIBUTE_UNUSED, 4291 bool *again, 4292 riscv_pcgp_relocs *pcgp_relocs, 4293 bool undefined_weak ATTRIBUTE_UNUSED) 4294 { 4295 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents; 4296 bfd_vma foff = symval - (sec_addr (sec) + rel->r_offset); 4297 bool near_zero = (symval + RISCV_IMM_REACH / 2) < RISCV_IMM_REACH; 4298 bfd_vma auipc, jalr; 4299 int rd, r_type, len = 4, rvc = elf_elfheader (abfd)->e_flags & EF_RISCV_RVC; 4300 4301 /* If the call crosses section boundaries, an alignment directive could 4302 cause the PC-relative offset to later increase, so we need to add in the 4303 max alignment of any section inclusive from the call to the target. 4304 Otherwise, we only need to use the alignment of the current section. */ 4305 if (VALID_JTYPE_IMM (foff)) 4306 { 4307 if (sym_sec->output_section == sec->output_section 4308 && sym_sec->output_section != bfd_abs_section_ptr) 4309 max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power; 4310 foff += ((bfd_signed_vma) foff < 0 ? -max_alignment : max_alignment); 4311 } 4312 4313 /* See if this function call can be shortened. */ 4314 if (!VALID_JTYPE_IMM (foff) && !(!bfd_link_pic (link_info) && near_zero)) 4315 return true; 4316 4317 /* Shorten the function call. */ 4318 BFD_ASSERT (rel->r_offset + 8 <= sec->size); 4319 4320 auipc = bfd_getl32 (contents + rel->r_offset); 4321 jalr = bfd_getl32 (contents + rel->r_offset + 4); 4322 rd = (jalr >> OP_SH_RD) & OP_MASK_RD; 4323 rvc = rvc && VALID_CJTYPE_IMM (foff); 4324 4325 /* C.J exists on RV32 and RV64, but C.JAL is RV32-only. */ 4326 rvc = rvc && (rd == 0 || (rd == X_RA && ARCH_SIZE == 32)); 4327 4328 if (rvc) 4329 { 4330 /* Relax to C.J[AL] rd, addr. */ 4331 r_type = R_RISCV_RVC_JUMP; 4332 auipc = rd == 0 ? MATCH_C_J : MATCH_C_JAL; 4333 len = 2; 4334 } 4335 else if (VALID_JTYPE_IMM (foff)) 4336 { 4337 /* Relax to JAL rd, addr. */ 4338 r_type = R_RISCV_JAL; 4339 auipc = MATCH_JAL | (rd << OP_SH_RD); 4340 } 4341 else 4342 { 4343 /* Near zero, relax to JALR rd, x0, addr. */ 4344 r_type = R_RISCV_LO12_I; 4345 auipc = MATCH_JALR | (rd << OP_SH_RD); 4346 } 4347 4348 /* Replace the R_RISCV_CALL reloc. */ 4349 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), r_type); 4350 /* Replace the AUIPC. */ 4351 riscv_put_insn (8 * len, auipc, contents + rel->r_offset); 4352 4353 /* Delete unnecessary JALR and reuse the R_RISCV_RELAX reloc. */ 4354 *again = true; 4355 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset + len, 8 - len, 4356 link_info, pcgp_relocs, rel + 1); 4357 } 4358 4359 /* Traverse all output sections and return the max alignment. */ 4360 4361 static bfd_vma 4362 _bfd_riscv_get_max_alignment (asection *sec) 4363 { 4364 unsigned int max_alignment_power = 0; 4365 asection *o; 4366 4367 for (o = sec->output_section->owner->sections; o != NULL; o = o->next) 4368 { 4369 if (o->alignment_power > max_alignment_power) 4370 max_alignment_power = o->alignment_power; 4371 } 4372 4373 return (bfd_vma) 1 << max_alignment_power; 4374 } 4375 4376 /* Relax non-PIC global variable references to GP-relative references. */ 4377 4378 static bool 4379 _bfd_riscv_relax_lui (bfd *abfd, 4380 asection *sec, 4381 asection *sym_sec, 4382 struct bfd_link_info *link_info, 4383 Elf_Internal_Rela *rel, 4384 bfd_vma symval, 4385 bfd_vma max_alignment, 4386 bfd_vma reserve_size, 4387 bool *again, 4388 riscv_pcgp_relocs *pcgp_relocs, 4389 bool undefined_weak) 4390 { 4391 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents; 4392 bfd_vma gp = riscv_global_pointer_value (link_info); 4393 int use_rvc = elf_elfheader (abfd)->e_flags & EF_RISCV_RVC; 4394 4395 BFD_ASSERT (rel->r_offset + 4 <= sec->size); 4396 4397 if (gp) 4398 { 4399 /* If gp and the symbol are in the same output section, which is not the 4400 abs section, then consider only that output section's alignment. */ 4401 struct bfd_link_hash_entry *h = 4402 bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, false, false, 4403 true); 4404 if (h->u.def.section->output_section == sym_sec->output_section 4405 && sym_sec->output_section != bfd_abs_section_ptr) 4406 max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power; 4407 } 4408 4409 /* Is the reference in range of x0 or gp? 4410 Valid gp range conservatively because of alignment issue. */ 4411 if (undefined_weak 4412 || (VALID_ITYPE_IMM (symval) 4413 || (symval >= gp 4414 && VALID_ITYPE_IMM (symval - gp + max_alignment + reserve_size)) 4415 || (symval < gp 4416 && VALID_ITYPE_IMM (symval - gp - max_alignment - reserve_size)))) 4417 { 4418 unsigned sym = ELFNN_R_SYM (rel->r_info); 4419 switch (ELFNN_R_TYPE (rel->r_info)) 4420 { 4421 case R_RISCV_LO12_I: 4422 if (undefined_weak) 4423 { 4424 /* Change the RS1 to zero. */ 4425 bfd_vma insn = bfd_getl32 (contents + rel->r_offset); 4426 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 4427 bfd_putl32 (insn, contents + rel->r_offset); 4428 } 4429 else 4430 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_I); 4431 return true; 4432 4433 case R_RISCV_LO12_S: 4434 if (undefined_weak) 4435 { 4436 /* Change the RS1 to zero. */ 4437 bfd_vma insn = bfd_getl32 (contents + rel->r_offset); 4438 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 4439 bfd_putl32 (insn, contents + rel->r_offset); 4440 } 4441 else 4442 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_S); 4443 return true; 4444 4445 case R_RISCV_HI20: 4446 /* Delete unnecessary LUI and reuse the reloc. */ 4447 *again = true; 4448 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset, 4, 4449 link_info, pcgp_relocs, rel); 4450 4451 default: 4452 abort (); 4453 } 4454 } 4455 4456 /* Can we relax LUI to C.LUI? Alignment might move the section forward; 4457 account for this assuming page alignment at worst. In the presence of 4458 RELRO segment the linker aligns it by one page size, therefore sections 4459 after the segment can be moved more than one page. */ 4460 4461 if (use_rvc 4462 && ELFNN_R_TYPE (rel->r_info) == R_RISCV_HI20 4463 && VALID_CITYPE_LUI_IMM (RISCV_CONST_HIGH_PART (symval)) 4464 && VALID_CITYPE_LUI_IMM (RISCV_CONST_HIGH_PART (symval) 4465 + (link_info->relro ? 2 * ELF_MAXPAGESIZE 4466 : ELF_MAXPAGESIZE))) 4467 { 4468 /* Replace LUI with C.LUI if legal (i.e., rd != x0 and rd != x2/sp). */ 4469 bfd_vma lui = bfd_getl32 (contents + rel->r_offset); 4470 unsigned rd = ((unsigned)lui >> OP_SH_RD) & OP_MASK_RD; 4471 if (rd == 0 || rd == X_SP) 4472 return true; 4473 4474 lui = (lui & (OP_MASK_RD << OP_SH_RD)) | MATCH_C_LUI; 4475 bfd_putl32 (lui, contents + rel->r_offset); 4476 4477 /* Replace the R_RISCV_HI20 reloc. */ 4478 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), R_RISCV_RVC_LUI); 4479 4480 /* Delete extra bytes and reuse the R_RISCV_RELAX reloc. */ 4481 *again = true; 4482 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset + 2, 2, 4483 link_info, pcgp_relocs, rel + 1); 4484 } 4485 4486 return true; 4487 } 4488 4489 /* Relax non-PIC TLS references to TP-relative references. */ 4490 4491 static bool 4492 _bfd_riscv_relax_tls_le (bfd *abfd, 4493 asection *sec, 4494 asection *sym_sec ATTRIBUTE_UNUSED, 4495 struct bfd_link_info *link_info, 4496 Elf_Internal_Rela *rel, 4497 bfd_vma symval, 4498 bfd_vma max_alignment ATTRIBUTE_UNUSED, 4499 bfd_vma reserve_size ATTRIBUTE_UNUSED, 4500 bool *again, 4501 riscv_pcgp_relocs *pcgp_relocs, 4502 bool undefined_weak ATTRIBUTE_UNUSED) 4503 { 4504 /* See if this symbol is in range of tp. */ 4505 if (RISCV_CONST_HIGH_PART (tpoff (link_info, symval)) != 0) 4506 return true; 4507 4508 BFD_ASSERT (rel->r_offset + 4 <= sec->size); 4509 switch (ELFNN_R_TYPE (rel->r_info)) 4510 { 4511 case R_RISCV_TPREL_LO12_I: 4512 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), R_RISCV_TPREL_I); 4513 return true; 4514 4515 case R_RISCV_TPREL_LO12_S: 4516 rel->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel->r_info), R_RISCV_TPREL_S); 4517 return true; 4518 4519 case R_RISCV_TPREL_HI20: 4520 case R_RISCV_TPREL_ADD: 4521 /* Delete unnecessary instruction and reuse the reloc. */ 4522 *again = true; 4523 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset, 4, link_info, 4524 pcgp_relocs, rel); 4525 4526 default: 4527 abort (); 4528 } 4529 } 4530 4531 /* Implement R_RISCV_ALIGN by deleting excess alignment NOPs. 4532 Once we've handled an R_RISCV_ALIGN, we can't relax anything else. */ 4533 4534 static bool 4535 _bfd_riscv_relax_align (bfd *abfd, asection *sec, 4536 asection *sym_sec, 4537 struct bfd_link_info *link_info, 4538 Elf_Internal_Rela *rel, 4539 bfd_vma symval, 4540 bfd_vma max_alignment ATTRIBUTE_UNUSED, 4541 bfd_vma reserve_size ATTRIBUTE_UNUSED, 4542 bool *again ATTRIBUTE_UNUSED, 4543 riscv_pcgp_relocs *pcgp_relocs ATTRIBUTE_UNUSED, 4544 bool undefined_weak ATTRIBUTE_UNUSED) 4545 { 4546 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents; 4547 bfd_vma alignment = 1, pos; 4548 while (alignment <= rel->r_addend) 4549 alignment *= 2; 4550 4551 symval -= rel->r_addend; 4552 bfd_vma aligned_addr = ((symval - 1) & ~(alignment - 1)) + alignment; 4553 bfd_vma nop_bytes = aligned_addr - symval; 4554 4555 /* Once we've handled an R_RISCV_ALIGN, we can't relax anything else. */ 4556 sec->sec_flg0 = true; 4557 4558 /* Make sure there are enough NOPs to actually achieve the alignment. */ 4559 if (rel->r_addend < nop_bytes) 4560 { 4561 _bfd_error_handler 4562 (_("%pB(%pA+%#" PRIx64 "): %" PRId64 " bytes required for alignment " 4563 "to %" PRId64 "-byte boundary, but only %" PRId64 " present"), 4564 abfd, sym_sec, (uint64_t) rel->r_offset, 4565 (int64_t) nop_bytes, (int64_t) alignment, (int64_t) rel->r_addend); 4566 bfd_set_error (bfd_error_bad_value); 4567 return false; 4568 } 4569 4570 /* Delete the reloc. */ 4571 rel->r_info = ELFNN_R_INFO (0, R_RISCV_NONE); 4572 4573 /* If the number of NOPs is already correct, there's nothing to do. */ 4574 if (nop_bytes == rel->r_addend) 4575 return true; 4576 4577 /* Write as many RISC-V NOPs as we need. */ 4578 for (pos = 0; pos < (nop_bytes & -4); pos += 4) 4579 bfd_putl32 (RISCV_NOP, contents + rel->r_offset + pos); 4580 4581 /* Write a final RVC NOP if need be. */ 4582 if (nop_bytes % 4 != 0) 4583 bfd_putl16 (RVC_NOP, contents + rel->r_offset + pos); 4584 4585 /* Delete excess bytes. */ 4586 return riscv_relax_delete_bytes (abfd, sec, rel->r_offset + nop_bytes, 4587 rel->r_addend - nop_bytes, link_info, 4588 NULL, NULL); 4589 } 4590 4591 /* Relax PC-relative references to GP-relative references. */ 4592 4593 static bool 4594 _bfd_riscv_relax_pc (bfd *abfd ATTRIBUTE_UNUSED, 4595 asection *sec, 4596 asection *sym_sec, 4597 struct bfd_link_info *link_info, 4598 Elf_Internal_Rela *rel, 4599 bfd_vma symval, 4600 bfd_vma max_alignment, 4601 bfd_vma reserve_size, 4602 bool *again, 4603 riscv_pcgp_relocs *pcgp_relocs, 4604 bool undefined_weak) 4605 { 4606 bfd_byte *contents = elf_section_data (sec)->this_hdr.contents; 4607 bfd_vma gp = riscv_global_pointer_value (link_info); 4608 4609 BFD_ASSERT (rel->r_offset + 4 <= sec->size); 4610 4611 /* Chain the _LO relocs to their cooresponding _HI reloc to compute the 4612 actual target address. */ 4613 riscv_pcgp_hi_reloc hi_reloc; 4614 memset (&hi_reloc, 0, sizeof (hi_reloc)); 4615 switch (ELFNN_R_TYPE (rel->r_info)) 4616 { 4617 case R_RISCV_PCREL_LO12_I: 4618 case R_RISCV_PCREL_LO12_S: 4619 { 4620 /* If the %lo has an addend, it isn't for the label pointing at the 4621 hi part instruction, but rather for the symbol pointed at by the 4622 hi part instruction. So we must subtract it here for the lookup. 4623 It is still used below in the final symbol address. */ 4624 bfd_vma hi_sec_off = symval - sec_addr (sym_sec) - rel->r_addend; 4625 riscv_pcgp_hi_reloc *hi = riscv_find_pcgp_hi_reloc (pcgp_relocs, 4626 hi_sec_off); 4627 if (hi == NULL) 4628 { 4629 riscv_record_pcgp_lo_reloc (pcgp_relocs, hi_sec_off); 4630 return true; 4631 } 4632 4633 hi_reloc = *hi; 4634 symval = hi_reloc.hi_addr; 4635 sym_sec = hi_reloc.sym_sec; 4636 4637 /* We can not know whether the undefined weak symbol is referenced 4638 according to the information of R_RISCV_PCREL_LO12_I/S. Therefore, 4639 we have to record the 'undefined_weak' flag when handling the 4640 corresponding R_RISCV_HI20 reloc in riscv_record_pcgp_hi_reloc. */ 4641 undefined_weak = hi_reloc.undefined_weak; 4642 } 4643 break; 4644 4645 case R_RISCV_PCREL_HI20: 4646 /* Mergeable symbols and code might later move out of range. */ 4647 if (! undefined_weak 4648 && sym_sec->flags & (SEC_MERGE | SEC_CODE)) 4649 return true; 4650 4651 /* If the cooresponding lo relocation has already been seen then it's not 4652 safe to relax this relocation. */ 4653 if (riscv_find_pcgp_lo_reloc (pcgp_relocs, rel->r_offset)) 4654 return true; 4655 4656 break; 4657 4658 default: 4659 abort (); 4660 } 4661 4662 if (gp) 4663 { 4664 /* If gp and the symbol are in the same output section, which is not the 4665 abs section, then consider only that output section's alignment. */ 4666 struct bfd_link_hash_entry *h = 4667 bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, false, false, 4668 true); 4669 if (h->u.def.section->output_section == sym_sec->output_section 4670 && sym_sec->output_section != bfd_abs_section_ptr) 4671 max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power; 4672 } 4673 4674 /* Is the reference in range of x0 or gp? 4675 Valid gp range conservatively because of alignment issue. */ 4676 if (undefined_weak 4677 || (VALID_ITYPE_IMM (symval) 4678 || (symval >= gp 4679 && VALID_ITYPE_IMM (symval - gp + max_alignment + reserve_size)) 4680 || (symval < gp 4681 && VALID_ITYPE_IMM (symval - gp - max_alignment - reserve_size)))) 4682 { 4683 unsigned sym = hi_reloc.hi_sym; 4684 switch (ELFNN_R_TYPE (rel->r_info)) 4685 { 4686 case R_RISCV_PCREL_LO12_I: 4687 if (undefined_weak) 4688 { 4689 /* Change the RS1 to zero, and then modify the relocation 4690 type to R_RISCV_LO12_I. */ 4691 bfd_vma insn = bfd_getl32 (contents + rel->r_offset); 4692 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 4693 bfd_putl32 (insn, contents + rel->r_offset); 4694 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_LO12_I); 4695 rel->r_addend = hi_reloc.hi_addend; 4696 } 4697 else 4698 { 4699 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_I); 4700 rel->r_addend += hi_reloc.hi_addend; 4701 } 4702 return true; 4703 4704 case R_RISCV_PCREL_LO12_S: 4705 if (undefined_weak) 4706 { 4707 /* Change the RS1 to zero, and then modify the relocation 4708 type to R_RISCV_LO12_S. */ 4709 bfd_vma insn = bfd_getl32 (contents + rel->r_offset); 4710 insn &= ~(OP_MASK_RS1 << OP_SH_RS1); 4711 bfd_putl32 (insn, contents + rel->r_offset); 4712 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_LO12_S); 4713 rel->r_addend = hi_reloc.hi_addend; 4714 } 4715 else 4716 { 4717 rel->r_info = ELFNN_R_INFO (sym, R_RISCV_GPREL_S); 4718 rel->r_addend += hi_reloc.hi_addend; 4719 } 4720 return true; 4721 4722 case R_RISCV_PCREL_HI20: 4723 riscv_record_pcgp_hi_reloc (pcgp_relocs, 4724 rel->r_offset, 4725 rel->r_addend, 4726 symval, 4727 ELFNN_R_SYM(rel->r_info), 4728 sym_sec, 4729 undefined_weak); 4730 /* Delete unnecessary AUIPC and reuse the reloc. */ 4731 *again = true; 4732 riscv_relax_delete_bytes (abfd, sec, rel->r_offset, 4, link_info, 4733 pcgp_relocs, rel); 4734 return true; 4735 4736 default: 4737 abort (); 4738 } 4739 } 4740 4741 return true; 4742 } 4743 4744 /* Called by after_allocation to set the information of data segment 4745 before relaxing. */ 4746 4747 void 4748 bfd_elfNN_riscv_set_data_segment_info (struct bfd_link_info *info, 4749 int *data_segment_phase) 4750 { 4751 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info); 4752 htab->data_segment_phase = data_segment_phase; 4753 } 4754 4755 /* Relax a section. 4756 4757 Pass 0: Shortens code sequences for LUI/CALL/TPREL/PCREL relocs. 4758 Pass 1: Deletes the bytes that PCREL relaxation in pass 0 made obsolete. 4759 Pass 2: Which cannot be disabled, handles code alignment directives. */ 4760 4761 static bool 4762 _bfd_riscv_relax_section (bfd *abfd, asection *sec, 4763 struct bfd_link_info *info, 4764 bool *again) 4765 { 4766 Elf_Internal_Shdr *symtab_hdr = &elf_symtab_hdr (abfd); 4767 struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (info); 4768 struct bfd_elf_section_data *data = elf_section_data (sec); 4769 Elf_Internal_Rela *relocs; 4770 bool ret = false; 4771 unsigned int i; 4772 bfd_vma max_alignment, reserve_size = 0; 4773 riscv_pcgp_relocs pcgp_relocs; 4774 4775 *again = false; 4776 4777 if (bfd_link_relocatable (info) 4778 || sec->sec_flg0 4779 || (sec->flags & SEC_RELOC) == 0 4780 || sec->reloc_count == 0 4781 || (info->disable_target_specific_optimizations 4782 && info->relax_pass == 0) 4783 /* The exp_seg_relro_adjust is enum phase_enum (0x4), 4784 and defined in ld/ldexp.h. */ 4785 || *(htab->data_segment_phase) == 4) 4786 return true; 4787 4788 riscv_init_pcgp_relocs (&pcgp_relocs); 4789 4790 /* Read this BFD's relocs if we haven't done so already. */ 4791 if (data->relocs) 4792 relocs = data->relocs; 4793 else if (!(relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL, 4794 info->keep_memory))) 4795 goto fail; 4796 4797 if (htab) 4798 { 4799 max_alignment = htab->max_alignment; 4800 if (max_alignment == (bfd_vma) -1) 4801 { 4802 max_alignment = _bfd_riscv_get_max_alignment (sec); 4803 htab->max_alignment = max_alignment; 4804 } 4805 } 4806 else 4807 max_alignment = _bfd_riscv_get_max_alignment (sec); 4808 4809 /* Examine and consider relaxing each reloc. */ 4810 for (i = 0; i < sec->reloc_count; i++) 4811 { 4812 asection *sym_sec; 4813 Elf_Internal_Rela *rel = relocs + i; 4814 relax_func_t relax_func; 4815 int type = ELFNN_R_TYPE (rel->r_info); 4816 bfd_vma symval; 4817 char symtype; 4818 bool undefined_weak = false; 4819 4820 relax_func = NULL; 4821 riscv_relax_delete_bytes = NULL; 4822 if (info->relax_pass == 0) 4823 { 4824 if (type == R_RISCV_CALL 4825 || type == R_RISCV_CALL_PLT) 4826 relax_func = _bfd_riscv_relax_call; 4827 else if (type == R_RISCV_HI20 4828 || type == R_RISCV_LO12_I 4829 || type == R_RISCV_LO12_S) 4830 relax_func = _bfd_riscv_relax_lui; 4831 else if (type == R_RISCV_TPREL_HI20 4832 || type == R_RISCV_TPREL_ADD 4833 || type == R_RISCV_TPREL_LO12_I 4834 || type == R_RISCV_TPREL_LO12_S) 4835 relax_func = _bfd_riscv_relax_tls_le; 4836 else if (!bfd_link_pic (info) 4837 && (type == R_RISCV_PCREL_HI20 4838 || type == R_RISCV_PCREL_LO12_I 4839 || type == R_RISCV_PCREL_LO12_S)) 4840 relax_func = _bfd_riscv_relax_pc; 4841 else 4842 continue; 4843 riscv_relax_delete_bytes = _riscv_relax_delete_piecewise; 4844 4845 /* Only relax this reloc if it is paired with R_RISCV_RELAX. */ 4846 if (i == sec->reloc_count - 1 4847 || ELFNN_R_TYPE ((rel + 1)->r_info) != R_RISCV_RELAX 4848 || rel->r_offset != (rel + 1)->r_offset) 4849 continue; 4850 4851 /* Skip over the R_RISCV_RELAX. */ 4852 i++; 4853 } 4854 else if (info->relax_pass == 1 && type == R_RISCV_ALIGN) 4855 { 4856 relax_func = _bfd_riscv_relax_align; 4857 riscv_relax_delete_bytes = _riscv_relax_delete_immediate; 4858 } 4859 else 4860 continue; 4861 4862 data->relocs = relocs; 4863 4864 /* Read this BFD's contents if we haven't done so already. */ 4865 if (!data->this_hdr.contents 4866 && !bfd_malloc_and_get_section (abfd, sec, &data->this_hdr.contents)) 4867 goto fail; 4868 4869 /* Read this BFD's symbols if we haven't done so already. */ 4870 if (symtab_hdr->sh_info != 0 4871 && !symtab_hdr->contents 4872 && !(symtab_hdr->contents = 4873 (unsigned char *) bfd_elf_get_elf_syms (abfd, symtab_hdr, 4874 symtab_hdr->sh_info, 4875 0, NULL, NULL, NULL))) 4876 goto fail; 4877 4878 /* Get the value of the symbol referred to by the reloc. */ 4879 if (ELFNN_R_SYM (rel->r_info) < symtab_hdr->sh_info) 4880 { 4881 /* A local symbol. */ 4882 Elf_Internal_Sym *isym = ((Elf_Internal_Sym *) symtab_hdr->contents 4883 + ELFNN_R_SYM (rel->r_info)); 4884 reserve_size = (isym->st_size - rel->r_addend) > isym->st_size 4885 ? 0 : isym->st_size - rel->r_addend; 4886 4887 /* Relocate against local STT_GNU_IFUNC symbol. we have created 4888 a fake global symbol entry for this, so deal with the local ifunc 4889 as a global. */ 4890 if (ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC) 4891 continue; 4892 4893 if (isym->st_shndx == SHN_UNDEF) 4894 sym_sec = sec, symval = rel->r_offset; 4895 else 4896 { 4897 BFD_ASSERT (isym->st_shndx < elf_numsections (abfd)); 4898 sym_sec = elf_elfsections (abfd)[isym->st_shndx]->bfd_section; 4899 #if 0 4900 /* The purpose of this code is unknown. It breaks linker scripts 4901 for embedded development that place sections at address zero. 4902 This code is believed to be unnecessary. Disabling it but not 4903 yet removing it, in case something breaks. */ 4904 if (sec_addr (sym_sec) == 0) 4905 continue; 4906 #endif 4907 symval = isym->st_value; 4908 } 4909 symtype = ELF_ST_TYPE (isym->st_info); 4910 } 4911 else 4912 { 4913 unsigned long indx; 4914 struct elf_link_hash_entry *h; 4915 4916 indx = ELFNN_R_SYM (rel->r_info) - symtab_hdr->sh_info; 4917 h = elf_sym_hashes (abfd)[indx]; 4918 4919 while (h->root.type == bfd_link_hash_indirect 4920 || h->root.type == bfd_link_hash_warning) 4921 h = (struct elf_link_hash_entry *) h->root.u.i.link; 4922 4923 /* Disable the relaxation for ifunc. */ 4924 if (h != NULL && h->type == STT_GNU_IFUNC) 4925 continue; 4926 4927 if (h->root.type == bfd_link_hash_undefweak 4928 && (relax_func == _bfd_riscv_relax_lui 4929 || relax_func == _bfd_riscv_relax_pc)) 4930 { 4931 /* For the lui and auipc relaxations, since the symbol 4932 value of an undefined weak symbol is always be zero, 4933 we can optimize the patterns into a single LI/MV/ADDI 4934 instruction. 4935 4936 Note that, creating shared libraries and pie output may 4937 break the rule above. Fortunately, since we do not relax 4938 pc relocs when creating shared libraries and pie output, 4939 and the absolute address access for R_RISCV_HI20 isn't 4940 allowed when "-fPIC" is set, the problem of creating shared 4941 libraries can not happen currently. Once we support the 4942 auipc relaxations when creating shared libraries, then we will 4943 need the more rigorous checking for this optimization. */ 4944 undefined_weak = true; 4945 } 4946 4947 /* This line has to match the check in riscv_elf_relocate_section 4948 in the R_RISCV_CALL[_PLT] case. */ 4949 if (bfd_link_pic (info) && h->plt.offset != MINUS_ONE) 4950 { 4951 sym_sec = htab->elf.splt; 4952 symval = h->plt.offset; 4953 } 4954 else if (undefined_weak) 4955 { 4956 symval = 0; 4957 sym_sec = bfd_und_section_ptr; 4958 } 4959 else if ((h->root.type == bfd_link_hash_defined 4960 || h->root.type == bfd_link_hash_defweak) 4961 && h->root.u.def.section != NULL 4962 && h->root.u.def.section->output_section != NULL) 4963 { 4964 symval = h->root.u.def.value; 4965 sym_sec = h->root.u.def.section; 4966 } 4967 else 4968 continue; 4969 4970 if (h->type != STT_FUNC) 4971 reserve_size = 4972 (h->size - rel->r_addend) > h->size ? 0 : h->size - rel->r_addend; 4973 symtype = h->type; 4974 } 4975 4976 if (sym_sec->sec_info_type == SEC_INFO_TYPE_MERGE 4977 && (sym_sec->flags & SEC_MERGE)) 4978 { 4979 /* At this stage in linking, no SEC_MERGE symbol has been 4980 adjusted, so all references to such symbols need to be 4981 passed through _bfd_merged_section_offset. (Later, in 4982 relocate_section, all SEC_MERGE symbols *except* for 4983 section symbols have been adjusted.) 4984 4985 gas may reduce relocations against symbols in SEC_MERGE 4986 sections to a relocation against the section symbol when 4987 the original addend was zero. When the reloc is against 4988 a section symbol we should include the addend in the 4989 offset passed to _bfd_merged_section_offset, since the 4990 location of interest is the original symbol. On the 4991 other hand, an access to "sym+addend" where "sym" is not 4992 a section symbol should not include the addend; Such an 4993 access is presumed to be an offset from "sym"; The 4994 location of interest is just "sym". */ 4995 if (symtype == STT_SECTION) 4996 symval += rel->r_addend; 4997 4998 symval = _bfd_merged_section_offset (abfd, &sym_sec, 4999 elf_section_data (sym_sec)->sec_info, 5000 symval); 5001 5002 if (symtype != STT_SECTION) 5003 symval += rel->r_addend; 5004 } 5005 else 5006 symval += rel->r_addend; 5007 5008 symval += sec_addr (sym_sec); 5009 5010 if (!relax_func (abfd, sec, sym_sec, info, rel, symval, 5011 max_alignment, reserve_size, again, 5012 &pcgp_relocs, undefined_weak)) 5013 goto fail; 5014 } 5015 5016 /* Resolve R_RISCV_DELETE relocations. */ 5017 if (!riscv_relax_resolve_delete_relocs (abfd, sec, info, relocs)) 5018 goto fail; 5019 5020 ret = true; 5021 5022 fail: 5023 if (relocs != data->relocs) 5024 free (relocs); 5025 riscv_free_pcgp_relocs (&pcgp_relocs, abfd, sec); 5026 5027 return ret; 5028 } 5029 5030 #if ARCH_SIZE == 32 5031 # define PRSTATUS_SIZE 204 5032 # define PRSTATUS_OFFSET_PR_CURSIG 12 5033 # define PRSTATUS_OFFSET_PR_PID 24 5034 # define PRSTATUS_OFFSET_PR_REG 72 5035 # define ELF_GREGSET_T_SIZE 128 5036 # define PRPSINFO_SIZE 128 5037 # define PRPSINFO_OFFSET_PR_PID 16 5038 # define PRPSINFO_OFFSET_PR_FNAME 32 5039 # define PRPSINFO_OFFSET_PR_PSARGS 48 5040 # define PRPSINFO_PR_FNAME_LENGTH 16 5041 # define PRPSINFO_PR_PSARGS_LENGTH 80 5042 #else 5043 # define PRSTATUS_SIZE 376 5044 # define PRSTATUS_OFFSET_PR_CURSIG 12 5045 # define PRSTATUS_OFFSET_PR_PID 32 5046 # define PRSTATUS_OFFSET_PR_REG 112 5047 # define ELF_GREGSET_T_SIZE 256 5048 # define PRPSINFO_SIZE 136 5049 # define PRPSINFO_OFFSET_PR_PID 24 5050 # define PRPSINFO_OFFSET_PR_FNAME 40 5051 # define PRPSINFO_OFFSET_PR_PSARGS 56 5052 # define PRPSINFO_PR_FNAME_LENGTH 16 5053 # define PRPSINFO_PR_PSARGS_LENGTH 80 5054 #endif 5055 5056 /* Write PRSTATUS and PRPSINFO note into core file. This will be called 5057 before the generic code in elf.c. By checking the compiler defines we 5058 only perform any action here if the generic code would otherwise not be 5059 able to help us. The intention is that bare metal core dumps (where the 5060 prstatus_t and/or prpsinfo_t might not be available) will use this code, 5061 while non bare metal tools will use the generic elf code. */ 5062 5063 static char * 5064 riscv_write_core_note (bfd *abfd ATTRIBUTE_UNUSED, 5065 char *buf ATTRIBUTE_UNUSED, 5066 int *bufsiz ATTRIBUTE_UNUSED, 5067 int note_type ATTRIBUTE_UNUSED, ...) 5068 { 5069 switch (note_type) 5070 { 5071 default: 5072 return NULL; 5073 5074 #if !defined (HAVE_PRPSINFO_T) 5075 case NT_PRPSINFO: 5076 { 5077 char data[PRPSINFO_SIZE] ATTRIBUTE_NONSTRING; 5078 va_list ap; 5079 5080 va_start (ap, note_type); 5081 memset (data, 0, sizeof (data)); 5082 strncpy (data + PRPSINFO_OFFSET_PR_FNAME, va_arg (ap, const char *), 5083 PRPSINFO_PR_FNAME_LENGTH); 5084 #if GCC_VERSION == 8000 || GCC_VERSION == 8001 5085 DIAGNOSTIC_PUSH; 5086 /* GCC 8.0 and 8.1 warn about 80 equals destination size with 5087 -Wstringop-truncation: 5088 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85643 5089 */ 5090 DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION; 5091 #endif 5092 strncpy (data + PRPSINFO_OFFSET_PR_PSARGS, va_arg (ap, const char *), 5093 PRPSINFO_PR_PSARGS_LENGTH); 5094 #if GCC_VERSION == 8000 || GCC_VERSION == 8001 5095 DIAGNOSTIC_POP; 5096 #endif 5097 va_end (ap); 5098 return elfcore_write_note (abfd, buf, bufsiz, 5099 "CORE", note_type, data, sizeof (data)); 5100 } 5101 #endif /* !HAVE_PRPSINFO_T */ 5102 5103 #if !defined (HAVE_PRSTATUS_T) 5104 case NT_PRSTATUS: 5105 { 5106 char data[PRSTATUS_SIZE]; 5107 va_list ap; 5108 long pid; 5109 int cursig; 5110 const void *greg; 5111 5112 va_start (ap, note_type); 5113 memset (data, 0, sizeof(data)); 5114 pid = va_arg (ap, long); 5115 bfd_put_32 (abfd, pid, data + PRSTATUS_OFFSET_PR_PID); 5116 cursig = va_arg (ap, int); 5117 bfd_put_16 (abfd, cursig, data + PRSTATUS_OFFSET_PR_CURSIG); 5118 greg = va_arg (ap, const void *); 5119 memcpy (data + PRSTATUS_OFFSET_PR_REG, greg, 5120 PRSTATUS_SIZE - PRSTATUS_OFFSET_PR_REG - ARCH_SIZE / 8); 5121 va_end (ap); 5122 return elfcore_write_note (abfd, buf, bufsiz, 5123 "CORE", note_type, data, sizeof (data)); 5124 } 5125 #endif /* !HAVE_PRSTATUS_T */ 5126 } 5127 } 5128 5129 /* Support for core dump NOTE sections. */ 5130 5131 static bool 5132 riscv_elf_grok_prstatus (bfd *abfd, Elf_Internal_Note *note) 5133 { 5134 switch (note->descsz) 5135 { 5136 default: 5137 return false; 5138 5139 case PRSTATUS_SIZE: /* sizeof(struct elf_prstatus) on Linux/RISC-V. */ 5140 /* pr_cursig */ 5141 elf_tdata (abfd)->core->signal 5142 = bfd_get_16 (abfd, note->descdata + PRSTATUS_OFFSET_PR_CURSIG); 5143 5144 /* pr_pid */ 5145 elf_tdata (abfd)->core->lwpid 5146 = bfd_get_32 (abfd, note->descdata + PRSTATUS_OFFSET_PR_PID); 5147 break; 5148 } 5149 5150 /* Make a ".reg/999" section. */ 5151 return _bfd_elfcore_make_pseudosection (abfd, ".reg", ELF_GREGSET_T_SIZE, 5152 note->descpos + PRSTATUS_OFFSET_PR_REG); 5153 } 5154 5155 static bool 5156 riscv_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note) 5157 { 5158 switch (note->descsz) 5159 { 5160 default: 5161 return false; 5162 5163 case PRPSINFO_SIZE: /* sizeof(struct elf_prpsinfo) on Linux/RISC-V. */ 5164 /* pr_pid */ 5165 elf_tdata (abfd)->core->pid 5166 = bfd_get_32 (abfd, note->descdata + PRPSINFO_OFFSET_PR_PID); 5167 5168 /* pr_fname */ 5169 elf_tdata (abfd)->core->program = _bfd_elfcore_strndup 5170 (abfd, note->descdata + PRPSINFO_OFFSET_PR_FNAME, 5171 PRPSINFO_PR_FNAME_LENGTH); 5172 5173 /* pr_psargs */ 5174 elf_tdata (abfd)->core->command = _bfd_elfcore_strndup 5175 (abfd, note->descdata + PRPSINFO_OFFSET_PR_PSARGS, 5176 PRPSINFO_PR_PSARGS_LENGTH); 5177 break; 5178 } 5179 5180 /* Note that for some reason, a spurious space is tacked 5181 onto the end of the args in some (at least one anyway) 5182 implementations, so strip it off if it exists. */ 5183 5184 { 5185 char *command = elf_tdata (abfd)->core->command; 5186 int n = strlen (command); 5187 5188 if (0 < n && command[n - 1] == ' ') 5189 command[n - 1] = '\0'; 5190 } 5191 5192 return true; 5193 } 5194 5195 /* Set the right mach type. */ 5196 5197 static bool 5198 riscv_elf_object_p (bfd *abfd) 5199 { 5200 /* There are only two mach types in RISCV currently. */ 5201 if (strcmp (abfd->xvec->name, "elf32-littleriscv") == 0 5202 || strcmp (abfd->xvec->name, "elf32-bigriscv") == 0) 5203 bfd_default_set_arch_mach (abfd, bfd_arch_riscv, bfd_mach_riscv32); 5204 else 5205 bfd_default_set_arch_mach (abfd, bfd_arch_riscv, bfd_mach_riscv64); 5206 5207 return true; 5208 } 5209 5210 /* Determine whether an object attribute tag takes an integer, a 5211 string or both. */ 5212 5213 static int 5214 riscv_elf_obj_attrs_arg_type (int tag) 5215 { 5216 return (tag & 1) != 0 ? ATTR_TYPE_FLAG_STR_VAL : ATTR_TYPE_FLAG_INT_VAL; 5217 } 5218 5219 /* Do not choose mapping symbols as a function name. */ 5220 5221 static bfd_size_type 5222 riscv_maybe_function_sym (const asymbol *sym, 5223 asection *sec, 5224 bfd_vma *code_off) 5225 { 5226 if (sym->flags & BSF_LOCAL 5227 && riscv_elf_is_mapping_symbols (sym->name)) 5228 return 0; 5229 5230 return _bfd_elf_maybe_function_sym (sym, sec, code_off); 5231 } 5232 5233 /* Treat the following cases as target special symbols, they are 5234 usually omitted. */ 5235 5236 static bool 5237 riscv_elf_is_target_special_symbol (bfd *abfd, asymbol *sym) 5238 { 5239 /* PR27584, local and empty symbols. Since they are usually 5240 generated for pcrel relocations. */ 5241 return (!strcmp (sym->name, "") 5242 || _bfd_elf_is_local_label_name (abfd, sym->name) 5243 /* PR27916, mapping symbols. */ 5244 || riscv_elf_is_mapping_symbols (sym->name)); 5245 } 5246 5247 static int 5248 riscv_elf_additional_program_headers (bfd *abfd, 5249 struct bfd_link_info *info ATTRIBUTE_UNUSED) 5250 { 5251 int ret = 0; 5252 5253 /* See if we need a PT_RISCV_ATTRIBUTES segment. */ 5254 if (bfd_get_section_by_name (abfd, RISCV_ATTRIBUTES_SECTION_NAME)) 5255 ++ret; 5256 5257 return ret; 5258 } 5259 5260 static bool 5261 riscv_elf_modify_segment_map (bfd *abfd, 5262 struct bfd_link_info *info ATTRIBUTE_UNUSED) 5263 { 5264 asection *s; 5265 struct elf_segment_map *m, **pm; 5266 size_t amt; 5267 5268 /* If there is a .riscv.attributes section, we need a PT_RISCV_ATTRIBUTES 5269 segment. */ 5270 s = bfd_get_section_by_name (abfd, RISCV_ATTRIBUTES_SECTION_NAME); 5271 if (s != NULL) 5272 { 5273 for (m = elf_seg_map (abfd); m != NULL; m = m->next) 5274 if (m->p_type == PT_RISCV_ATTRIBUTES) 5275 break; 5276 /* If there is already a PT_RISCV_ATTRIBUTES header, avoid adding 5277 another. */ 5278 if (m == NULL) 5279 { 5280 amt = sizeof (*m); 5281 m = bfd_zalloc (abfd, amt); 5282 if (m == NULL) 5283 return false; 5284 5285 m->p_type = PT_RISCV_ATTRIBUTES; 5286 m->count = 1; 5287 m->sections[0] = s; 5288 5289 /* We want to put it after the PHDR and INTERP segments. */ 5290 pm = &elf_seg_map (abfd); 5291 while (*pm != NULL 5292 && ((*pm)->p_type == PT_PHDR 5293 || (*pm)->p_type == PT_INTERP)) 5294 pm = &(*pm)->next; 5295 5296 m->next = *pm; 5297 *pm = m; 5298 } 5299 } 5300 5301 return true; 5302 } 5303 5304 /* Merge non-visibility st_other attributes. */ 5305 5306 static void 5307 riscv_elf_merge_symbol_attribute (struct elf_link_hash_entry *h, 5308 unsigned int st_other, 5309 bool definition ATTRIBUTE_UNUSED, 5310 bool dynamic ATTRIBUTE_UNUSED) 5311 { 5312 unsigned int isym_sto = st_other & ~ELF_ST_VISIBILITY (-1); 5313 unsigned int h_sto = h->other & ~ELF_ST_VISIBILITY (-1); 5314 5315 if (isym_sto == h_sto) 5316 return; 5317 5318 if (isym_sto & ~STO_RISCV_VARIANT_CC) 5319 _bfd_error_handler (_("unknown attribute for symbol `%s': 0x%02x"), 5320 h->root.root.string, isym_sto); 5321 5322 if (isym_sto & STO_RISCV_VARIANT_CC) 5323 h->other |= STO_RISCV_VARIANT_CC; 5324 } 5325 5326 #define TARGET_LITTLE_SYM riscv_elfNN_vec 5327 #define TARGET_LITTLE_NAME "elfNN-littleriscv" 5328 #define TARGET_BIG_SYM riscv_elfNN_be_vec 5329 #define TARGET_BIG_NAME "elfNN-bigriscv" 5330 5331 #define elf_backend_reloc_type_class riscv_reloc_type_class 5332 5333 #define bfd_elfNN_bfd_reloc_name_lookup riscv_reloc_name_lookup 5334 #define bfd_elfNN_bfd_link_hash_table_create riscv_elf_link_hash_table_create 5335 #define bfd_elfNN_bfd_reloc_type_lookup riscv_reloc_type_lookup 5336 #define bfd_elfNN_bfd_merge_private_bfd_data \ 5337 _bfd_riscv_elf_merge_private_bfd_data 5338 #define bfd_elfNN_bfd_is_target_special_symbol riscv_elf_is_target_special_symbol 5339 5340 #define elf_backend_copy_indirect_symbol riscv_elf_copy_indirect_symbol 5341 #define elf_backend_create_dynamic_sections riscv_elf_create_dynamic_sections 5342 #define elf_backend_check_relocs riscv_elf_check_relocs 5343 #define elf_backend_adjust_dynamic_symbol riscv_elf_adjust_dynamic_symbol 5344 #define elf_backend_size_dynamic_sections riscv_elf_size_dynamic_sections 5345 #define elf_backend_relocate_section riscv_elf_relocate_section 5346 #define elf_backend_finish_dynamic_symbol riscv_elf_finish_dynamic_symbol 5347 #define elf_backend_finish_dynamic_sections riscv_elf_finish_dynamic_sections 5348 #define elf_backend_plt_sym_val riscv_elf_plt_sym_val 5349 #define elf_backend_grok_prstatus riscv_elf_grok_prstatus 5350 #define elf_backend_grok_psinfo riscv_elf_grok_psinfo 5351 #define elf_backend_object_p riscv_elf_object_p 5352 #define elf_backend_write_core_note riscv_write_core_note 5353 #define elf_backend_maybe_function_sym riscv_maybe_function_sym 5354 #define elf_info_to_howto_rel NULL 5355 #define elf_info_to_howto riscv_info_to_howto_rela 5356 #define bfd_elfNN_bfd_relax_section _bfd_riscv_relax_section 5357 #define bfd_elfNN_mkobject elfNN_riscv_mkobject 5358 #define elf_backend_additional_program_headers \ 5359 riscv_elf_additional_program_headers 5360 #define elf_backend_modify_segment_map riscv_elf_modify_segment_map 5361 #define elf_backend_merge_symbol_attribute riscv_elf_merge_symbol_attribute 5362 5363 #define elf_backend_init_index_section _bfd_elf_init_1_index_section 5364 5365 #define elf_backend_can_gc_sections 1 5366 #define elf_backend_can_refcount 1 5367 #define elf_backend_want_got_plt 1 5368 #define elf_backend_plt_readonly 1 5369 #define elf_backend_plt_alignment 4 5370 #define elf_backend_want_plt_sym 1 5371 #define elf_backend_got_header_size (ARCH_SIZE / 8) 5372 #define elf_backend_want_dynrelro 1 5373 #define elf_backend_rela_normal 1 5374 #define elf_backend_default_execstack 0 5375 5376 #undef elf_backend_obj_attrs_vendor 5377 #define elf_backend_obj_attrs_vendor "riscv" 5378 #undef elf_backend_obj_attrs_arg_type 5379 #define elf_backend_obj_attrs_arg_type riscv_elf_obj_attrs_arg_type 5380 #undef elf_backend_obj_attrs_section_type 5381 #define elf_backend_obj_attrs_section_type SHT_RISCV_ATTRIBUTES 5382 #undef elf_backend_obj_attrs_section 5383 #define elf_backend_obj_attrs_section RISCV_ATTRIBUTES_SECTION_NAME 5384 5385 #include "elfNN-target.h" 5386