elf64-mmix.c revision 1.1.1.11
1 /* MMIX-specific support for 64-bit ELF. 2 Copyright (C) 2001-2025 Free Software Foundation, Inc. 3 Contributed by Hans-Peter Nilsson <hp (at) bitrange.com> 4 5 This file is part of BFD, the Binary File Descriptor library. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20 MA 02110-1301, USA. */ 21 22 23 /* No specific ABI or "processor-specific supplement" defined. */ 24 25 /* TODO: 26 - "Traditional" linker relaxation (shrinking whole sections). 27 - Merge reloc stubs jumping to same location. 28 - GETA stub relaxation (call a stub for out of range new 29 R_MMIX_GETA_STUBBABLE). */ 30 31 #include "sysdep.h" 32 #include "bfd.h" 33 #include "libbfd.h" 34 #include "elf-bfd.h" 35 #include "elf/mmix.h" 36 #include "opcode/mmix.h" 37 38 #define MINUS_ONE (((bfd_vma) 0) - 1) 39 40 #define MAX_PUSHJ_STUB_SIZE (5 * 4) 41 42 /* Put these everywhere in new code. */ 43 #define FATAL_DEBUG \ 44 _bfd_abort (__FILE__, __LINE__, \ 45 "Internal: Non-debugged code (test-case missing)") 46 47 #define BAD_CASE(x) \ 48 _bfd_abort (__FILE__, __LINE__, \ 49 "bad case for " #x) 50 51 struct _mmix_elf_section_data 52 { 53 struct bfd_elf_section_data elf; 54 union 55 { 56 struct bpo_reloc_section_info *reloc; 57 struct bpo_greg_section_info *greg; 58 } bpo; 59 60 struct pushj_stub_info 61 { 62 /* Maximum number of stubs needed for this section. */ 63 bfd_size_type n_pushj_relocs; 64 65 /* Size of stubs after a mmix_elf_relax_section round. */ 66 bfd_size_type stubs_size_sum; 67 68 /* Per-reloc stubs_size_sum information. The stubs_size_sum member is the sum 69 of these. Allocated in mmix_elf_check_common_relocs. */ 70 bfd_size_type *stub_size; 71 72 /* Offset of next stub during relocation. Somewhat redundant with the 73 above: error coverage is easier and we don't have to reset the 74 stubs_size_sum for relocation. */ 75 bfd_size_type stub_offset; 76 } pjs; 77 78 /* Whether there has been a warning that this section could not be 79 linked due to a specific cause. FIXME: a way to access the 80 linker info or output section, then stuff the limiter guard 81 there. */ 82 bool has_warned_bpo; 83 bool has_warned_pushj; 84 }; 85 86 #define mmix_elf_section_data(sec) \ 87 ((struct _mmix_elf_section_data *) elf_section_data (sec)) 88 89 /* For each section containing a base-plus-offset (BPO) reloc, we attach 90 this struct as mmix_elf_section_data (section)->bpo, which is otherwise 91 NULL. */ 92 struct bpo_reloc_section_info 93 { 94 /* The base is 1; this is the first number in this section. */ 95 size_t first_base_plus_offset_reloc; 96 97 /* Number of BPO-relocs in this section. */ 98 size_t n_bpo_relocs_this_section; 99 100 /* Running index, used at relocation time. */ 101 size_t bpo_index; 102 103 /* We don't have access to the bfd_link_info struct in 104 mmix_final_link_relocate. What we really want to get at is the 105 global single struct greg_relocation, so we stash it here. */ 106 asection *bpo_greg_section; 107 }; 108 109 /* Helper struct (in global context) for the one below. 110 There's one of these created for every BPO reloc. */ 111 struct bpo_reloc_request 112 { 113 bfd_vma value; 114 115 /* Valid after relaxation. The base is 0; the first register number 116 must be added. The offset is in range 0..255. */ 117 size_t regindex; 118 size_t offset; 119 120 /* The order number for this BPO reloc, corresponding to the order in 121 which BPO relocs were found. Used to create an index after reloc 122 requests are sorted. */ 123 size_t bpo_reloc_no; 124 125 /* Set when the value is computed. Better than coding "guard values" 126 into the other members. Is FALSE only for BPO relocs in a GC:ed 127 section. */ 128 bool valid; 129 }; 130 131 /* We attach this as mmix_elf_section_data (sec)->bpo in the linker-allocated 132 greg contents section (MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME), 133 which is linked into the register contents section 134 (MMIX_REG_CONTENTS_SECTION_NAME). This section is created by the 135 linker; using the same hook as for usual with BPO relocs does not 136 collide. */ 137 struct bpo_greg_section_info 138 { 139 /* After GC, this reflects the number of remaining, non-excluded 140 BPO-relocs. */ 141 size_t n_bpo_relocs; 142 143 /* This is the number of allocated bpo_reloc_requests; the size of 144 sorted_indexes. Valid after the check.*relocs functions are called 145 for all incoming sections. It includes the number of BPO relocs in 146 sections that were GC:ed. */ 147 size_t n_max_bpo_relocs; 148 149 /* A counter used to find out when to fold the BPO gregs, since we 150 don't have a single "after-relaxation" hook. */ 151 size_t n_remaining_bpo_relocs_this_relaxation_round; 152 153 /* The number of linker-allocated GREGs resulting from BPO relocs. 154 This is an approximation after _bfd_mmix_before_linker_allocation 155 and supposedly accurate after mmix_elf_relax_section is called for 156 all incoming non-collected sections. */ 157 size_t n_allocated_bpo_gregs; 158 159 /* Index into reloc_request[], sorted on increasing "value", secondary 160 by increasing index for strict sorting order. */ 161 size_t *bpo_reloc_indexes; 162 163 /* An array of all relocations, with the "value" member filled in by 164 the relaxation function. */ 165 struct bpo_reloc_request *reloc_request; 166 }; 167 168 169 extern bool mmix_elf_final_link (bfd *, struct bfd_link_info *); 170 171 extern void mmix_elf_symbol_processing (bfd *, asymbol *); 172 173 /* Only intended to be called from a debugger. */ 174 extern void mmix_dump_bpo_gregs 175 (struct bfd_link_info *, void (*) (const char *, ...)); 176 177 static void 178 mmix_set_relaxable_size (bfd *, asection *, void *); 179 static bfd_reloc_status_type 180 mmix_elf_reloc (bfd *, arelent *, asymbol *, void *, 181 asection *, bfd *, char **); 182 static bfd_reloc_status_type 183 mmix_final_link_relocate (reloc_howto_type *, asection *, bfd_byte *, bfd_vma, 184 bfd_signed_vma, bfd_vma, const char *, asection *, 185 char **); 186 187 188 /* Watch out: this currently needs to have elements with the same index as 189 their R_MMIX_ number. */ 190 static reloc_howto_type elf_mmix_howto_table[] = 191 { 192 /* This reloc does nothing. */ 193 HOWTO (R_MMIX_NONE, /* type */ 194 0, /* rightshift */ 195 0, /* size */ 196 0, /* bitsize */ 197 false, /* pc_relative */ 198 0, /* bitpos */ 199 complain_overflow_dont, /* complain_on_overflow */ 200 bfd_elf_generic_reloc, /* special_function */ 201 "R_MMIX_NONE", /* name */ 202 false, /* partial_inplace */ 203 0, /* src_mask */ 204 0, /* dst_mask */ 205 false), /* pcrel_offset */ 206 207 /* An 8 bit absolute relocation. */ 208 HOWTO (R_MMIX_8, /* type */ 209 0, /* rightshift */ 210 1, /* size */ 211 8, /* bitsize */ 212 false, /* pc_relative */ 213 0, /* bitpos */ 214 complain_overflow_bitfield, /* complain_on_overflow */ 215 bfd_elf_generic_reloc, /* special_function */ 216 "R_MMIX_8", /* name */ 217 false, /* partial_inplace */ 218 0, /* src_mask */ 219 0xff, /* dst_mask */ 220 false), /* pcrel_offset */ 221 222 /* An 16 bit absolute relocation. */ 223 HOWTO (R_MMIX_16, /* type */ 224 0, /* rightshift */ 225 2, /* size */ 226 16, /* bitsize */ 227 false, /* pc_relative */ 228 0, /* bitpos */ 229 complain_overflow_bitfield, /* complain_on_overflow */ 230 bfd_elf_generic_reloc, /* special_function */ 231 "R_MMIX_16", /* name */ 232 false, /* partial_inplace */ 233 0, /* src_mask */ 234 0xffff, /* dst_mask */ 235 false), /* pcrel_offset */ 236 237 /* An 24 bit absolute relocation. */ 238 HOWTO (R_MMIX_24, /* type */ 239 0, /* rightshift */ 240 4, /* size */ 241 24, /* bitsize */ 242 false, /* pc_relative */ 243 0, /* bitpos */ 244 complain_overflow_bitfield, /* complain_on_overflow */ 245 bfd_elf_generic_reloc, /* special_function */ 246 "R_MMIX_24", /* name */ 247 false, /* partial_inplace */ 248 ~0xffffff, /* src_mask */ 249 0xffffff, /* dst_mask */ 250 false), /* pcrel_offset */ 251 252 /* A 32 bit absolute relocation. */ 253 HOWTO (R_MMIX_32, /* type */ 254 0, /* rightshift */ 255 4, /* size */ 256 32, /* bitsize */ 257 false, /* pc_relative */ 258 0, /* bitpos */ 259 complain_overflow_bitfield, /* complain_on_overflow */ 260 bfd_elf_generic_reloc, /* special_function */ 261 "R_MMIX_32", /* name */ 262 false, /* partial_inplace */ 263 0, /* src_mask */ 264 0xffffffff, /* dst_mask */ 265 false), /* pcrel_offset */ 266 267 /* 64 bit relocation. */ 268 HOWTO (R_MMIX_64, /* type */ 269 0, /* rightshift */ 270 8, /* size */ 271 64, /* bitsize */ 272 false, /* pc_relative */ 273 0, /* bitpos */ 274 complain_overflow_bitfield, /* complain_on_overflow */ 275 bfd_elf_generic_reloc, /* special_function */ 276 "R_MMIX_64", /* name */ 277 false, /* partial_inplace */ 278 0, /* src_mask */ 279 MINUS_ONE, /* dst_mask */ 280 false), /* pcrel_offset */ 281 282 /* An 8 bit PC-relative relocation. */ 283 HOWTO (R_MMIX_PC_8, /* type */ 284 0, /* rightshift */ 285 1, /* size */ 286 8, /* bitsize */ 287 true, /* pc_relative */ 288 0, /* bitpos */ 289 complain_overflow_bitfield, /* complain_on_overflow */ 290 bfd_elf_generic_reloc, /* special_function */ 291 "R_MMIX_PC_8", /* name */ 292 false, /* partial_inplace */ 293 0, /* src_mask */ 294 0xff, /* dst_mask */ 295 true), /* pcrel_offset */ 296 297 /* An 16 bit PC-relative relocation. */ 298 HOWTO (R_MMIX_PC_16, /* type */ 299 0, /* rightshift */ 300 2, /* size */ 301 16, /* bitsize */ 302 true, /* pc_relative */ 303 0, /* bitpos */ 304 complain_overflow_bitfield, /* complain_on_overflow */ 305 bfd_elf_generic_reloc, /* special_function */ 306 "R_MMIX_PC_16", /* name */ 307 false, /* partial_inplace */ 308 0, /* src_mask */ 309 0xffff, /* dst_mask */ 310 true), /* pcrel_offset */ 311 312 /* An 24 bit PC-relative relocation. */ 313 HOWTO (R_MMIX_PC_24, /* type */ 314 0, /* rightshift */ 315 4, /* size */ 316 24, /* bitsize */ 317 true, /* pc_relative */ 318 0, /* bitpos */ 319 complain_overflow_bitfield, /* complain_on_overflow */ 320 bfd_elf_generic_reloc, /* special_function */ 321 "R_MMIX_PC_24", /* name */ 322 false, /* partial_inplace */ 323 ~0xffffff, /* src_mask */ 324 0xffffff, /* dst_mask */ 325 true), /* pcrel_offset */ 326 327 /* A 32 bit absolute PC-relative relocation. */ 328 HOWTO (R_MMIX_PC_32, /* type */ 329 0, /* rightshift */ 330 4, /* size */ 331 32, /* bitsize */ 332 true, /* pc_relative */ 333 0, /* bitpos */ 334 complain_overflow_bitfield, /* complain_on_overflow */ 335 bfd_elf_generic_reloc, /* special_function */ 336 "R_MMIX_PC_32", /* name */ 337 false, /* partial_inplace */ 338 0, /* src_mask */ 339 0xffffffff, /* dst_mask */ 340 true), /* pcrel_offset */ 341 342 /* 64 bit PC-relative relocation. */ 343 HOWTO (R_MMIX_PC_64, /* type */ 344 0, /* rightshift */ 345 8, /* size */ 346 64, /* bitsize */ 347 true, /* pc_relative */ 348 0, /* bitpos */ 349 complain_overflow_bitfield, /* complain_on_overflow */ 350 bfd_elf_generic_reloc, /* special_function */ 351 "R_MMIX_PC_64", /* name */ 352 false, /* partial_inplace */ 353 0, /* src_mask */ 354 MINUS_ONE, /* dst_mask */ 355 true), /* pcrel_offset */ 356 357 /* GNU extension to record C++ vtable hierarchy. */ 358 HOWTO (R_MMIX_GNU_VTINHERIT, /* type */ 359 0, /* rightshift */ 360 0, /* size */ 361 0, /* bitsize */ 362 false, /* pc_relative */ 363 0, /* bitpos */ 364 complain_overflow_dont, /* complain_on_overflow */ 365 NULL, /* special_function */ 366 "R_MMIX_GNU_VTINHERIT", /* name */ 367 false, /* partial_inplace */ 368 0, /* src_mask */ 369 0, /* dst_mask */ 370 true), /* pcrel_offset */ 371 372 /* GNU extension to record C++ vtable member usage. */ 373 HOWTO (R_MMIX_GNU_VTENTRY, /* type */ 374 0, /* rightshift */ 375 0, /* size */ 376 0, /* bitsize */ 377 false, /* pc_relative */ 378 0, /* bitpos */ 379 complain_overflow_dont, /* complain_on_overflow */ 380 _bfd_elf_rel_vtable_reloc_fn, /* special_function */ 381 "R_MMIX_GNU_VTENTRY", /* name */ 382 false, /* partial_inplace */ 383 0, /* src_mask */ 384 0, /* dst_mask */ 385 false), /* pcrel_offset */ 386 387 /* The GETA relocation is supposed to get any address that could 388 possibly be reached by the GETA instruction. It can silently expand 389 to get a 64-bit operand, but will complain if any of the two least 390 significant bits are set. The howto members reflect a simple GETA. */ 391 HOWTO (R_MMIX_GETA, /* type */ 392 2, /* rightshift */ 393 4, /* size */ 394 19, /* bitsize */ 395 true, /* pc_relative */ 396 0, /* bitpos */ 397 complain_overflow_signed, /* complain_on_overflow */ 398 mmix_elf_reloc, /* special_function */ 399 "R_MMIX_GETA", /* name */ 400 false, /* partial_inplace */ 401 ~0x0100ffff, /* src_mask */ 402 0x0100ffff, /* dst_mask */ 403 true), /* pcrel_offset */ 404 405 HOWTO (R_MMIX_GETA_1, /* type */ 406 2, /* rightshift */ 407 4, /* size */ 408 19, /* bitsize */ 409 true, /* pc_relative */ 410 0, /* bitpos */ 411 complain_overflow_signed, /* complain_on_overflow */ 412 mmix_elf_reloc, /* special_function */ 413 "R_MMIX_GETA_1", /* name */ 414 false, /* partial_inplace */ 415 ~0x0100ffff, /* src_mask */ 416 0x0100ffff, /* dst_mask */ 417 true), /* pcrel_offset */ 418 419 HOWTO (R_MMIX_GETA_2, /* type */ 420 2, /* rightshift */ 421 4, /* size */ 422 19, /* bitsize */ 423 true, /* pc_relative */ 424 0, /* bitpos */ 425 complain_overflow_signed, /* complain_on_overflow */ 426 mmix_elf_reloc, /* special_function */ 427 "R_MMIX_GETA_2", /* name */ 428 false, /* partial_inplace */ 429 ~0x0100ffff, /* src_mask */ 430 0x0100ffff, /* dst_mask */ 431 true), /* pcrel_offset */ 432 433 HOWTO (R_MMIX_GETA_3, /* type */ 434 2, /* rightshift */ 435 4, /* size */ 436 19, /* bitsize */ 437 true, /* pc_relative */ 438 0, /* bitpos */ 439 complain_overflow_signed, /* complain_on_overflow */ 440 mmix_elf_reloc, /* special_function */ 441 "R_MMIX_GETA_3", /* name */ 442 false, /* partial_inplace */ 443 ~0x0100ffff, /* src_mask */ 444 0x0100ffff, /* dst_mask */ 445 true), /* pcrel_offset */ 446 447 /* The conditional branches are supposed to reach any (code) address. 448 It can silently expand to a 64-bit operand, but will emit an error if 449 any of the two least significant bits are set. The howto members 450 reflect a simple branch. */ 451 HOWTO (R_MMIX_CBRANCH, /* type */ 452 2, /* rightshift */ 453 4, /* size */ 454 19, /* bitsize */ 455 true, /* pc_relative */ 456 0, /* bitpos */ 457 complain_overflow_signed, /* complain_on_overflow */ 458 mmix_elf_reloc, /* special_function */ 459 "R_MMIX_CBRANCH", /* name */ 460 false, /* partial_inplace */ 461 ~0x0100ffff, /* src_mask */ 462 0x0100ffff, /* dst_mask */ 463 true), /* pcrel_offset */ 464 465 HOWTO (R_MMIX_CBRANCH_J, /* type */ 466 2, /* rightshift */ 467 4, /* size */ 468 19, /* bitsize */ 469 true, /* pc_relative */ 470 0, /* bitpos */ 471 complain_overflow_signed, /* complain_on_overflow */ 472 mmix_elf_reloc, /* special_function */ 473 "R_MMIX_CBRANCH_J", /* name */ 474 false, /* partial_inplace */ 475 ~0x0100ffff, /* src_mask */ 476 0x0100ffff, /* dst_mask */ 477 true), /* pcrel_offset */ 478 479 HOWTO (R_MMIX_CBRANCH_1, /* type */ 480 2, /* rightshift */ 481 4, /* size */ 482 19, /* bitsize */ 483 true, /* pc_relative */ 484 0, /* bitpos */ 485 complain_overflow_signed, /* complain_on_overflow */ 486 mmix_elf_reloc, /* special_function */ 487 "R_MMIX_CBRANCH_1", /* name */ 488 false, /* partial_inplace */ 489 ~0x0100ffff, /* src_mask */ 490 0x0100ffff, /* dst_mask */ 491 true), /* pcrel_offset */ 492 493 HOWTO (R_MMIX_CBRANCH_2, /* type */ 494 2, /* rightshift */ 495 4, /* size */ 496 19, /* bitsize */ 497 true, /* pc_relative */ 498 0, /* bitpos */ 499 complain_overflow_signed, /* complain_on_overflow */ 500 mmix_elf_reloc, /* special_function */ 501 "R_MMIX_CBRANCH_2", /* name */ 502 false, /* partial_inplace */ 503 ~0x0100ffff, /* src_mask */ 504 0x0100ffff, /* dst_mask */ 505 true), /* pcrel_offset */ 506 507 HOWTO (R_MMIX_CBRANCH_3, /* type */ 508 2, /* rightshift */ 509 4, /* size */ 510 19, /* bitsize */ 511 true, /* pc_relative */ 512 0, /* bitpos */ 513 complain_overflow_signed, /* complain_on_overflow */ 514 mmix_elf_reloc, /* special_function */ 515 "R_MMIX_CBRANCH_3", /* name */ 516 false, /* partial_inplace */ 517 ~0x0100ffff, /* src_mask */ 518 0x0100ffff, /* dst_mask */ 519 true), /* pcrel_offset */ 520 521 /* The PUSHJ instruction can reach any (code) address, as long as it's 522 the beginning of a function (no usable restriction). It can silently 523 expand to a 64-bit operand, but will emit an error if any of the two 524 least significant bits are set. It can also expand into a call to a 525 stub; see R_MMIX_PUSHJ_STUBBABLE. The howto members reflect a simple 526 PUSHJ. */ 527 HOWTO (R_MMIX_PUSHJ, /* type */ 528 2, /* rightshift */ 529 4, /* size */ 530 19, /* bitsize */ 531 true, /* pc_relative */ 532 0, /* bitpos */ 533 complain_overflow_signed, /* complain_on_overflow */ 534 mmix_elf_reloc, /* special_function */ 535 "R_MMIX_PUSHJ", /* name */ 536 false, /* partial_inplace */ 537 ~0x0100ffff, /* src_mask */ 538 0x0100ffff, /* dst_mask */ 539 true), /* pcrel_offset */ 540 541 HOWTO (R_MMIX_PUSHJ_1, /* type */ 542 2, /* rightshift */ 543 4, /* size */ 544 19, /* bitsize */ 545 true, /* pc_relative */ 546 0, /* bitpos */ 547 complain_overflow_signed, /* complain_on_overflow */ 548 mmix_elf_reloc, /* special_function */ 549 "R_MMIX_PUSHJ_1", /* name */ 550 false, /* partial_inplace */ 551 ~0x0100ffff, /* src_mask */ 552 0x0100ffff, /* dst_mask */ 553 true), /* pcrel_offset */ 554 555 HOWTO (R_MMIX_PUSHJ_2, /* type */ 556 2, /* rightshift */ 557 4, /* size */ 558 19, /* bitsize */ 559 true, /* pc_relative */ 560 0, /* bitpos */ 561 complain_overflow_signed, /* complain_on_overflow */ 562 mmix_elf_reloc, /* special_function */ 563 "R_MMIX_PUSHJ_2", /* name */ 564 false, /* partial_inplace */ 565 ~0x0100ffff, /* src_mask */ 566 0x0100ffff, /* dst_mask */ 567 true), /* pcrel_offset */ 568 569 HOWTO (R_MMIX_PUSHJ_3, /* type */ 570 2, /* rightshift */ 571 4, /* size */ 572 19, /* bitsize */ 573 true, /* pc_relative */ 574 0, /* bitpos */ 575 complain_overflow_signed, /* complain_on_overflow */ 576 mmix_elf_reloc, /* special_function */ 577 "R_MMIX_PUSHJ_3", /* name */ 578 false, /* partial_inplace */ 579 ~0x0100ffff, /* src_mask */ 580 0x0100ffff, /* dst_mask */ 581 true), /* pcrel_offset */ 582 583 /* A JMP is supposed to reach any (code) address. By itself, it can 584 reach +-64M; the expansion can reach all 64 bits. Note that the 64M 585 limit is soon reached if you link the program in wildly different 586 memory segments. The howto members reflect a trivial JMP. */ 587 HOWTO (R_MMIX_JMP, /* type */ 588 2, /* rightshift */ 589 4, /* size */ 590 27, /* bitsize */ 591 true, /* pc_relative */ 592 0, /* bitpos */ 593 complain_overflow_signed, /* complain_on_overflow */ 594 mmix_elf_reloc, /* special_function */ 595 "R_MMIX_JMP", /* name */ 596 false, /* partial_inplace */ 597 ~0x1ffffff, /* src_mask */ 598 0x1ffffff, /* dst_mask */ 599 true), /* pcrel_offset */ 600 601 HOWTO (R_MMIX_JMP_1, /* type */ 602 2, /* rightshift */ 603 4, /* size */ 604 27, /* bitsize */ 605 true, /* pc_relative */ 606 0, /* bitpos */ 607 complain_overflow_signed, /* complain_on_overflow */ 608 mmix_elf_reloc, /* special_function */ 609 "R_MMIX_JMP_1", /* name */ 610 false, /* partial_inplace */ 611 ~0x1ffffff, /* src_mask */ 612 0x1ffffff, /* dst_mask */ 613 true), /* pcrel_offset */ 614 615 HOWTO (R_MMIX_JMP_2, /* type */ 616 2, /* rightshift */ 617 4, /* size */ 618 27, /* bitsize */ 619 true, /* pc_relative */ 620 0, /* bitpos */ 621 complain_overflow_signed, /* complain_on_overflow */ 622 mmix_elf_reloc, /* special_function */ 623 "R_MMIX_JMP_2", /* name */ 624 false, /* partial_inplace */ 625 ~0x1ffffff, /* src_mask */ 626 0x1ffffff, /* dst_mask */ 627 true), /* pcrel_offset */ 628 629 HOWTO (R_MMIX_JMP_3, /* type */ 630 2, /* rightshift */ 631 4, /* size */ 632 27, /* bitsize */ 633 true, /* pc_relative */ 634 0, /* bitpos */ 635 complain_overflow_signed, /* complain_on_overflow */ 636 mmix_elf_reloc, /* special_function */ 637 "R_MMIX_JMP_3", /* name */ 638 false, /* partial_inplace */ 639 ~0x1ffffff, /* src_mask */ 640 0x1ffffff, /* dst_mask */ 641 true), /* pcrel_offset */ 642 643 /* When we don't emit link-time-relaxable code from the assembler, or 644 when relaxation has done all it can do, these relocs are used. For 645 GETA/PUSHJ/branches. */ 646 HOWTO (R_MMIX_ADDR19, /* type */ 647 2, /* rightshift */ 648 4, /* size */ 649 19, /* bitsize */ 650 true, /* pc_relative */ 651 0, /* bitpos */ 652 complain_overflow_signed, /* complain_on_overflow */ 653 mmix_elf_reloc, /* special_function */ 654 "R_MMIX_ADDR19", /* name */ 655 false, /* partial_inplace */ 656 ~0x0100ffff, /* src_mask */ 657 0x0100ffff, /* dst_mask */ 658 true), /* pcrel_offset */ 659 660 /* For JMP. */ 661 HOWTO (R_MMIX_ADDR27, /* type */ 662 2, /* rightshift */ 663 4, /* size */ 664 27, /* bitsize */ 665 true, /* pc_relative */ 666 0, /* bitpos */ 667 complain_overflow_signed, /* complain_on_overflow */ 668 mmix_elf_reloc, /* special_function */ 669 "R_MMIX_ADDR27", /* name */ 670 false, /* partial_inplace */ 671 ~0x1ffffff, /* src_mask */ 672 0x1ffffff, /* dst_mask */ 673 true), /* pcrel_offset */ 674 675 /* A general register or the value 0..255. If a value, then the 676 instruction (offset -3) needs adjusting. */ 677 HOWTO (R_MMIX_REG_OR_BYTE, /* type */ 678 0, /* rightshift */ 679 2, /* size */ 680 8, /* bitsize */ 681 false, /* pc_relative */ 682 0, /* bitpos */ 683 complain_overflow_bitfield, /* complain_on_overflow */ 684 mmix_elf_reloc, /* special_function */ 685 "R_MMIX_REG_OR_BYTE", /* name */ 686 false, /* partial_inplace */ 687 0, /* src_mask */ 688 0xff, /* dst_mask */ 689 false), /* pcrel_offset */ 690 691 /* A general register. */ 692 HOWTO (R_MMIX_REG, /* type */ 693 0, /* rightshift */ 694 2, /* size */ 695 8, /* bitsize */ 696 false, /* pc_relative */ 697 0, /* bitpos */ 698 complain_overflow_bitfield, /* complain_on_overflow */ 699 mmix_elf_reloc, /* special_function */ 700 "R_MMIX_REG", /* name */ 701 false, /* partial_inplace */ 702 0, /* src_mask */ 703 0xff, /* dst_mask */ 704 false), /* pcrel_offset */ 705 706 /* A register plus an index, corresponding to the relocation expression. 707 The sizes must correspond to the valid range of the expression, while 708 the bitmasks correspond to what we store in the image. */ 709 HOWTO (R_MMIX_BASE_PLUS_OFFSET, /* type */ 710 0, /* rightshift */ 711 8, /* size */ 712 64, /* bitsize */ 713 false, /* pc_relative */ 714 0, /* bitpos */ 715 complain_overflow_bitfield, /* complain_on_overflow */ 716 mmix_elf_reloc, /* special_function */ 717 "R_MMIX_BASE_PLUS_OFFSET", /* name */ 718 false, /* partial_inplace */ 719 0, /* src_mask */ 720 0xffff, /* dst_mask */ 721 false), /* pcrel_offset */ 722 723 /* A "magic" relocation for a LOCAL expression, asserting that the 724 expression is less than the number of global registers. No actual 725 modification of the contents is done. Implementing this as a 726 relocation was less intrusive than e.g. putting such expressions in a 727 section to discard *after* relocation. */ 728 HOWTO (R_MMIX_LOCAL, /* type */ 729 0, /* rightshift */ 730 0, /* size */ 731 0, /* bitsize */ 732 false, /* pc_relative */ 733 0, /* bitpos */ 734 complain_overflow_dont, /* complain_on_overflow */ 735 mmix_elf_reloc, /* special_function */ 736 "R_MMIX_LOCAL", /* name */ 737 false, /* partial_inplace */ 738 0, /* src_mask */ 739 0, /* dst_mask */ 740 false), /* pcrel_offset */ 741 742 HOWTO (R_MMIX_PUSHJ_STUBBABLE, /* type */ 743 2, /* rightshift */ 744 4, /* size */ 745 19, /* bitsize */ 746 true, /* pc_relative */ 747 0, /* bitpos */ 748 complain_overflow_signed, /* complain_on_overflow */ 749 mmix_elf_reloc, /* special_function */ 750 "R_MMIX_PUSHJ_STUBBABLE", /* name */ 751 false, /* partial_inplace */ 752 ~0x0100ffff, /* src_mask */ 753 0x0100ffff, /* dst_mask */ 754 true) /* pcrel_offset */ 755 }; 756 757 758 /* Map BFD reloc types to MMIX ELF reloc types. */ 759 760 struct mmix_reloc_map 761 { 762 bfd_reloc_code_real_type bfd_reloc_val; 763 enum elf_mmix_reloc_type elf_reloc_val; 764 }; 765 766 767 static const struct mmix_reloc_map mmix_reloc_map[] = 768 { 769 {BFD_RELOC_NONE, R_MMIX_NONE}, 770 {BFD_RELOC_8, R_MMIX_8}, 771 {BFD_RELOC_16, R_MMIX_16}, 772 {BFD_RELOC_24, R_MMIX_24}, 773 {BFD_RELOC_32, R_MMIX_32}, 774 {BFD_RELOC_64, R_MMIX_64}, 775 {BFD_RELOC_8_PCREL, R_MMIX_PC_8}, 776 {BFD_RELOC_16_PCREL, R_MMIX_PC_16}, 777 {BFD_RELOC_24_PCREL, R_MMIX_PC_24}, 778 {BFD_RELOC_32_PCREL, R_MMIX_PC_32}, 779 {BFD_RELOC_64_PCREL, R_MMIX_PC_64}, 780 {BFD_RELOC_VTABLE_INHERIT, R_MMIX_GNU_VTINHERIT}, 781 {BFD_RELOC_VTABLE_ENTRY, R_MMIX_GNU_VTENTRY}, 782 {BFD_RELOC_MMIX_GETA, R_MMIX_GETA}, 783 {BFD_RELOC_MMIX_CBRANCH, R_MMIX_CBRANCH}, 784 {BFD_RELOC_MMIX_PUSHJ, R_MMIX_PUSHJ}, 785 {BFD_RELOC_MMIX_JMP, R_MMIX_JMP}, 786 {BFD_RELOC_MMIX_ADDR19, R_MMIX_ADDR19}, 787 {BFD_RELOC_MMIX_ADDR27, R_MMIX_ADDR27}, 788 {BFD_RELOC_MMIX_REG_OR_BYTE, R_MMIX_REG_OR_BYTE}, 789 {BFD_RELOC_MMIX_REG, R_MMIX_REG}, 790 {BFD_RELOC_MMIX_BASE_PLUS_OFFSET, R_MMIX_BASE_PLUS_OFFSET}, 791 {BFD_RELOC_MMIX_LOCAL, R_MMIX_LOCAL}, 792 {BFD_RELOC_MMIX_PUSHJ_STUBBABLE, R_MMIX_PUSHJ_STUBBABLE} 793 }; 794 795 static reloc_howto_type * 796 bfd_elf64_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, 797 bfd_reloc_code_real_type code) 798 { 799 unsigned int i; 800 801 for (i = 0; 802 i < sizeof (mmix_reloc_map) / sizeof (mmix_reloc_map[0]); 803 i++) 804 { 805 if (mmix_reloc_map[i].bfd_reloc_val == code) 806 return &elf_mmix_howto_table[mmix_reloc_map[i].elf_reloc_val]; 807 } 808 809 return NULL; 810 } 811 812 static reloc_howto_type * 813 bfd_elf64_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 814 const char *r_name) 815 { 816 unsigned int i; 817 818 for (i = 0; 819 i < sizeof (elf_mmix_howto_table) / sizeof (elf_mmix_howto_table[0]); 820 i++) 821 if (elf_mmix_howto_table[i].name != NULL 822 && strcasecmp (elf_mmix_howto_table[i].name, r_name) == 0) 823 return &elf_mmix_howto_table[i]; 824 825 return NULL; 826 } 827 828 static bool 829 mmix_elf_new_section_hook (bfd *abfd, asection *sec) 830 { 831 struct _mmix_elf_section_data *sdata; 832 833 sdata = bfd_zalloc (abfd, sizeof (*sdata)); 834 if (sdata == NULL) 835 return false; 836 sec->used_by_bfd = sdata; 837 838 return _bfd_elf_new_section_hook (abfd, sec); 839 } 840 841 842 /* This function performs the actual bitfiddling and sanity check for a 843 final relocation. Each relocation gets its *worst*-case expansion 844 in size when it arrives here; any reduction in size should have been 845 caught in linker relaxation earlier. When we get here, the relocation 846 looks like the smallest instruction with SWYM:s (nop:s) appended to the 847 max size. We fill in those nop:s. 848 849 R_MMIX_GETA: (FIXME: Relaxation should break this up in 1, 2, 3 tetra) 850 GETA $N,foo 851 -> 852 SETL $N,foo & 0xffff 853 INCML $N,(foo >> 16) & 0xffff 854 INCMH $N,(foo >> 32) & 0xffff 855 INCH $N,(foo >> 48) & 0xffff 856 857 R_MMIX_CBRANCH: (FIXME: Relaxation should break this up, but 858 condbranches needing relaxation might be rare enough to not be 859 worthwhile.) 860 [P]Bcc $N,foo 861 -> 862 [~P]B~cc $N,.+20 863 SETL $255,foo & ... 864 INCML ... 865 INCMH ... 866 INCH ... 867 GO $255,$255,0 868 869 R_MMIX_PUSHJ: (FIXME: Relaxation...) 870 PUSHJ $N,foo 871 -> 872 SETL $255,foo & ... 873 INCML ... 874 INCMH ... 875 INCH ... 876 PUSHGO $N,$255,0 877 878 R_MMIX_JMP: (FIXME: Relaxation...) 879 JMP foo 880 -> 881 SETL $255,foo & ... 882 INCML ... 883 INCMH ... 884 INCH ... 885 GO $255,$255,0 886 887 R_MMIX_ADDR19 and R_MMIX_ADDR27 are just filled in. */ 888 889 static bfd_reloc_status_type 890 mmix_elf_perform_relocation (asection *isec, reloc_howto_type *howto, 891 void *datap, bfd_vma addr, bfd_vma value, 892 char **error_message) 893 { 894 bfd *abfd = isec->owner; 895 bfd_reloc_status_type flag = bfd_reloc_ok; 896 bfd_reloc_status_type r; 897 int offs = 0; 898 int reg = 255; 899 900 /* The worst case bits are all similar SETL/INCML/INCMH/INCH sequences. 901 We handle the differences here and the common sequence later. */ 902 switch (howto->type) 903 { 904 case R_MMIX_GETA: 905 offs = 0; 906 reg = bfd_get_8 (abfd, (bfd_byte *) datap + 1); 907 908 /* We change to an absolute value. */ 909 value += addr; 910 break; 911 912 case R_MMIX_CBRANCH: 913 { 914 int in1 = bfd_get_16 (abfd, (bfd_byte *) datap) << 16; 915 916 /* Invert the condition and prediction bit, and set the offset 917 to five instructions ahead. 918 919 We *can* do better if we want to. If the branch is found to be 920 within limits, we could leave the branch as is; there'll just 921 be a bunch of NOP:s after it. But we shouldn't see this 922 sequence often enough that it's worth doing it. */ 923 924 bfd_put_32 (abfd, 925 (((in1 ^ ((PRED_INV_BIT | COND_INV_BIT) << 24)) & ~0xffff) 926 | (24/4)), 927 (bfd_byte *) datap); 928 929 /* Put a "GO $255,$255,0" after the common sequence. */ 930 bfd_put_32 (abfd, 931 ((GO_INSN_BYTE | IMM_OFFSET_BIT) << 24) | 0xffff00, 932 (bfd_byte *) datap + 20); 933 934 /* Common sequence starts at offset 4. */ 935 offs = 4; 936 937 /* We change to an absolute value. */ 938 value += addr; 939 } 940 break; 941 942 case R_MMIX_PUSHJ_STUBBABLE: 943 /* If the address fits, we're fine. */ 944 if ((value & 3) == 0 945 /* Note rightshift 0; see R_MMIX_JMP case below. */ 946 && (r = bfd_check_overflow (complain_overflow_signed, 947 howto->bitsize, 948 0, 949 bfd_arch_bits_per_address (abfd), 950 value)) == bfd_reloc_ok) 951 goto pcrel_mmix_reloc_fits; 952 else 953 { 954 bfd_size_type size = isec->rawsize ? isec->rawsize : isec->size; 955 956 /* We have the bytes at the PUSHJ insn and need to get the 957 position for the stub. There's supposed to be room allocated 958 for the stub. */ 959 bfd_byte *stubcontents 960 = ((bfd_byte *) datap 961 - (addr - (isec->output_section->vma + isec->output_offset)) 962 + size 963 + mmix_elf_section_data (isec)->pjs.stub_offset); 964 bfd_vma stubaddr; 965 966 if (mmix_elf_section_data (isec)->pjs.n_pushj_relocs == 0) 967 { 968 /* This shouldn't happen when linking to ELF or mmo, so 969 this is an attempt to link to "binary", right? We 970 can't access the output bfd, so we can't verify that 971 assumption. We only know that the critical 972 mmix_elf_check_common_relocs has not been called, 973 which happens when the output format is different 974 from the input format (and is not mmo). */ 975 if (! mmix_elf_section_data (isec)->has_warned_pushj) 976 { 977 /* For the first such error per input section, produce 978 a verbose message. */ 979 *error_message 980 = _("invalid input relocation when producing" 981 " non-ELF, non-mmo format output;" 982 " please use the objcopy program to convert from" 983 " ELF or mmo," 984 " or assemble using" 985 " \"-no-expand\" (for gcc, \"-Wa,-no-expand\""); 986 mmix_elf_section_data (isec)->has_warned_pushj = true; 987 return bfd_reloc_dangerous; 988 } 989 990 /* For subsequent errors, return this one, which is 991 rate-limited but looks a little bit different, 992 hopefully without affecting user-friendliness. */ 993 return bfd_reloc_overflow; 994 } 995 996 /* The address doesn't fit, so redirect the PUSHJ to the 997 location of the stub. */ 998 r = mmix_elf_perform_relocation (isec, 999 &elf_mmix_howto_table 1000 [R_MMIX_ADDR19], 1001 datap, 1002 addr, 1003 isec->output_section->vma 1004 + isec->output_offset 1005 + size 1006 + (mmix_elf_section_data (isec) 1007 ->pjs.stub_offset) 1008 - addr, 1009 error_message); 1010 if (r != bfd_reloc_ok) 1011 return r; 1012 1013 stubaddr 1014 = (isec->output_section->vma 1015 + isec->output_offset 1016 + size 1017 + mmix_elf_section_data (isec)->pjs.stub_offset); 1018 1019 /* We generate a simple JMP if that suffices, else the whole 5 1020 insn stub. */ 1021 if (bfd_check_overflow (complain_overflow_signed, 1022 elf_mmix_howto_table[R_MMIX_ADDR27].bitsize, 1023 0, 1024 bfd_arch_bits_per_address (abfd), 1025 addr + value - stubaddr) == bfd_reloc_ok) 1026 { 1027 bfd_put_32 (abfd, JMP_INSN_BYTE << 24, stubcontents); 1028 r = mmix_elf_perform_relocation (isec, 1029 &elf_mmix_howto_table 1030 [R_MMIX_ADDR27], 1031 stubcontents, 1032 stubaddr, 1033 value + addr - stubaddr, 1034 error_message); 1035 mmix_elf_section_data (isec)->pjs.stub_offset += 4; 1036 1037 if (size + mmix_elf_section_data (isec)->pjs.stub_offset 1038 > isec->size) 1039 abort (); 1040 1041 return r; 1042 } 1043 else 1044 { 1045 /* Put a "GO $255,0" after the common sequence. */ 1046 bfd_put_32 (abfd, 1047 ((GO_INSN_BYTE | IMM_OFFSET_BIT) << 24) 1048 | 0xff00, (bfd_byte *) stubcontents + 16); 1049 1050 /* Prepare for the general code to set the first part of the 1051 linker stub, and */ 1052 value += addr; 1053 datap = stubcontents; 1054 mmix_elf_section_data (isec)->pjs.stub_offset 1055 += MAX_PUSHJ_STUB_SIZE; 1056 } 1057 } 1058 break; 1059 1060 case R_MMIX_PUSHJ: 1061 { 1062 int inreg = bfd_get_8 (abfd, (bfd_byte *) datap + 1); 1063 1064 /* Put a "PUSHGO $N,$255,0" after the common sequence. */ 1065 bfd_put_32 (abfd, 1066 ((PUSHGO_INSN_BYTE | IMM_OFFSET_BIT) << 24) 1067 | (inreg << 16) 1068 | 0xff00, 1069 (bfd_byte *) datap + 16); 1070 1071 /* We change to an absolute value. */ 1072 value += addr; 1073 } 1074 break; 1075 1076 case R_MMIX_JMP: 1077 /* This one is a little special. If we get here on a non-relaxing 1078 link, and the destination is actually in range, we don't need to 1079 execute the nops. 1080 If so, we fall through to the bit-fiddling relocs. 1081 1082 FIXME: bfd_check_overflow seems broken; the relocation is 1083 rightshifted before testing, so supply a zero rightshift. */ 1084 1085 if (! ((value & 3) == 0 1086 && (r = bfd_check_overflow (complain_overflow_signed, 1087 howto->bitsize, 1088 0, 1089 bfd_arch_bits_per_address (abfd), 1090 value)) == bfd_reloc_ok)) 1091 { 1092 /* If the relocation doesn't fit in a JMP, we let the NOP:s be 1093 modified below, and put a "GO $255,$255,0" after the 1094 address-loading sequence. */ 1095 bfd_put_32 (abfd, 1096 ((GO_INSN_BYTE | IMM_OFFSET_BIT) << 24) 1097 | 0xffff00, 1098 (bfd_byte *) datap + 16); 1099 1100 /* We change to an absolute value. */ 1101 value += addr; 1102 break; 1103 } 1104 /* FALLTHROUGH. */ 1105 case R_MMIX_ADDR19: 1106 case R_MMIX_ADDR27: 1107 pcrel_mmix_reloc_fits: 1108 /* These must be in range, or else we emit an error. */ 1109 if ((value & 3) == 0 1110 /* Note rightshift 0; see above. */ 1111 && (r = bfd_check_overflow (complain_overflow_signed, 1112 howto->bitsize, 1113 0, 1114 bfd_arch_bits_per_address (abfd), 1115 value)) == bfd_reloc_ok) 1116 { 1117 bfd_vma in1 1118 = bfd_get_32 (abfd, (bfd_byte *) datap); 1119 bfd_vma highbit; 1120 1121 if ((bfd_signed_vma) value < 0) 1122 { 1123 highbit = 1 << 24; 1124 value += (1 << (howto->bitsize - 1)); 1125 } 1126 else 1127 highbit = 0; 1128 1129 value >>= 2; 1130 1131 bfd_put_32 (abfd, 1132 (in1 & howto->src_mask) 1133 | highbit 1134 | (value & howto->dst_mask), 1135 (bfd_byte *) datap); 1136 1137 return bfd_reloc_ok; 1138 } 1139 else 1140 return bfd_reloc_overflow; 1141 1142 case R_MMIX_BASE_PLUS_OFFSET: 1143 { 1144 struct bpo_reloc_section_info *bpodata 1145 = mmix_elf_section_data (isec)->bpo.reloc; 1146 asection *bpo_greg_section; 1147 struct bpo_greg_section_info *gregdata; 1148 size_t bpo_index; 1149 1150 if (bpodata == NULL) 1151 { 1152 /* This shouldn't happen when linking to ELF or mmo, so 1153 this is an attempt to link to "binary", right? We 1154 can't access the output bfd, so we can't verify that 1155 assumption. We only know that the critical 1156 mmix_elf_check_common_relocs has not been called, which 1157 happens when the output format is different from the 1158 input format (and is not mmo). */ 1159 if (! mmix_elf_section_data (isec)->has_warned_bpo) 1160 { 1161 /* For the first such error per input section, produce 1162 a verbose message. */ 1163 *error_message 1164 = _("invalid input relocation when producing" 1165 " non-ELF, non-mmo format output;" 1166 " please use the objcopy program to convert from" 1167 " ELF or mmo," 1168 " or compile using the gcc-option" 1169 " \"-mno-base-addresses\"."); 1170 mmix_elf_section_data (isec)->has_warned_bpo = true; 1171 return bfd_reloc_dangerous; 1172 } 1173 1174 /* For subsequent errors, return this one, which is 1175 rate-limited but looks a little bit different, 1176 hopefully without affecting user-friendliness. */ 1177 return bfd_reloc_overflow; 1178 } 1179 1180 bpo_greg_section = bpodata->bpo_greg_section; 1181 gregdata = mmix_elf_section_data (bpo_greg_section)->bpo.greg; 1182 bpo_index = gregdata->bpo_reloc_indexes[bpodata->bpo_index++]; 1183 1184 /* A consistency check: The value we now have in "relocation" must 1185 be the same as the value we stored for that relocation. It 1186 doesn't cost much, so can be left in at all times. */ 1187 if (value != gregdata->reloc_request[bpo_index].value) 1188 { 1189 _bfd_error_handler 1190 /* xgettext:c-format */ 1191 (_("%pB: Internal inconsistency error for value for\n\ 1192 linker-allocated global register: linked: %#" PRIx64 " != relaxed: %#" PRIx64 ""), 1193 isec->owner, 1194 (uint64_t) value, 1195 (uint64_t) gregdata->reloc_request[bpo_index].value); 1196 bfd_set_error (bfd_error_bad_value); 1197 return bfd_reloc_overflow; 1198 } 1199 1200 /* Then store the register number and offset for that register 1201 into datap and datap + 1 respectively. */ 1202 bfd_put_8 (abfd, 1203 gregdata->reloc_request[bpo_index].regindex 1204 + bpo_greg_section->output_section->vma / 8, 1205 datap); 1206 bfd_put_8 (abfd, 1207 gregdata->reloc_request[bpo_index].offset, 1208 ((unsigned char *) datap) + 1); 1209 return bfd_reloc_ok; 1210 } 1211 1212 case R_MMIX_REG_OR_BYTE: 1213 case R_MMIX_REG: 1214 if (value > 255) 1215 return bfd_reloc_overflow; 1216 bfd_put_8 (abfd, value, datap); 1217 return bfd_reloc_ok; 1218 1219 default: 1220 BAD_CASE (howto->type); 1221 } 1222 1223 /* This code adds the common SETL/INCML/INCMH/INCH worst-case 1224 sequence. */ 1225 1226 /* Lowest two bits must be 0. We return bfd_reloc_overflow for 1227 everything that looks strange. */ 1228 if (value & 3) 1229 flag = bfd_reloc_overflow; 1230 1231 bfd_put_32 (abfd, 1232 (SETL_INSN_BYTE << 24) | (value & 0xffff) | (reg << 16), 1233 (bfd_byte *) datap + offs); 1234 bfd_put_32 (abfd, 1235 (INCML_INSN_BYTE << 24) | ((value >> 16) & 0xffff) | (reg << 16), 1236 (bfd_byte *) datap + offs + 4); 1237 bfd_put_32 (abfd, 1238 (INCMH_INSN_BYTE << 24) | ((value >> 32) & 0xffff) | (reg << 16), 1239 (bfd_byte *) datap + offs + 8); 1240 bfd_put_32 (abfd, 1241 (INCH_INSN_BYTE << 24) | ((value >> 48) & 0xffff) | (reg << 16), 1242 (bfd_byte *) datap + offs + 12); 1243 1244 return flag; 1245 } 1246 1247 /* Set the howto pointer for an MMIX ELF reloc (type RELA). */ 1248 1249 static bool 1250 mmix_info_to_howto_rela (bfd *abfd, 1251 arelent *cache_ptr, 1252 Elf_Internal_Rela *dst) 1253 { 1254 unsigned int r_type; 1255 1256 r_type = ELF64_R_TYPE (dst->r_info); 1257 if (r_type >= (unsigned int) R_MMIX_max) 1258 { 1259 /* xgettext:c-format */ 1260 _bfd_error_handler (_("%pB: unsupported relocation type %#x"), 1261 abfd, r_type); 1262 bfd_set_error (bfd_error_bad_value); 1263 return false; 1264 } 1265 cache_ptr->howto = &elf_mmix_howto_table[r_type]; 1266 return true; 1267 } 1268 1269 /* Any MMIX-specific relocation gets here at assembly time or when linking 1270 to other formats (such as mmo); this is the relocation function from 1271 the reloc_table. We don't get here for final pure ELF linking. */ 1272 1273 static bfd_reloc_status_type 1274 mmix_elf_reloc (bfd *abfd, 1275 arelent *reloc_entry, 1276 asymbol *symbol, 1277 void * data, 1278 asection *input_section, 1279 bfd *output_bfd, 1280 char **error_message) 1281 { 1282 bfd_vma relocation; 1283 bfd_reloc_status_type r; 1284 asection *reloc_target_output_section; 1285 bfd_reloc_status_type flag = bfd_reloc_ok; 1286 bfd_vma output_base = 0; 1287 1288 r = bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data, 1289 input_section, output_bfd, error_message); 1290 1291 /* If that was all that was needed (i.e. this isn't a final link, only 1292 some segment adjustments), we're done. */ 1293 if (r != bfd_reloc_continue) 1294 return r; 1295 1296 if (bfd_is_und_section (symbol->section) 1297 && (symbol->flags & BSF_WEAK) == 0 1298 && output_bfd == (bfd *) NULL) 1299 return bfd_reloc_undefined; 1300 1301 /* Is the address of the relocation really within the section? */ 1302 if (reloc_entry->address > bfd_get_section_limit (abfd, input_section)) 1303 return bfd_reloc_outofrange; 1304 1305 /* Work out which section the relocation is targeted at and the 1306 initial relocation command value. */ 1307 1308 /* Get symbol value. (Common symbols are special.) */ 1309 if (bfd_is_com_section (symbol->section)) 1310 relocation = 0; 1311 else 1312 relocation = symbol->value; 1313 1314 reloc_target_output_section = bfd_asymbol_section (symbol)->output_section; 1315 1316 /* Here the variable relocation holds the final address of the symbol we 1317 are relocating against, plus any addend. */ 1318 if (output_bfd) 1319 output_base = 0; 1320 else 1321 output_base = reloc_target_output_section->vma; 1322 1323 relocation += output_base + symbol->section->output_offset; 1324 1325 if (output_bfd != (bfd *) NULL) 1326 { 1327 /* Add in supplied addend. */ 1328 relocation += reloc_entry->addend; 1329 1330 /* This is a partial relocation, and we want to apply the 1331 relocation to the reloc entry rather than the raw data. 1332 Modify the reloc inplace to reflect what we now know. */ 1333 reloc_entry->addend = relocation; 1334 reloc_entry->address += input_section->output_offset; 1335 return flag; 1336 } 1337 1338 return mmix_final_link_relocate (reloc_entry->howto, input_section, 1339 data, reloc_entry->address, 1340 reloc_entry->addend, relocation, 1341 bfd_asymbol_name (symbol), 1342 reloc_target_output_section, 1343 error_message); 1344 } 1345 1346 /* Relocate an MMIX ELF section. Modified from elf32-fr30.c; look to it 1348 for guidance if you're thinking of copying this. */ 1349 1350 static int 1351 mmix_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED, 1352 struct bfd_link_info *info, 1353 bfd *input_bfd, 1354 asection *input_section, 1355 bfd_byte *contents, 1356 Elf_Internal_Rela *relocs, 1357 Elf_Internal_Sym *local_syms, 1358 asection **local_sections) 1359 { 1360 Elf_Internal_Shdr *symtab_hdr; 1361 struct elf_link_hash_entry **sym_hashes; 1362 Elf_Internal_Rela *rel; 1363 Elf_Internal_Rela *relend; 1364 bfd_size_type size; 1365 size_t pjsno = 0; 1366 1367 size = input_section->rawsize ? input_section->rawsize : input_section->size; 1368 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; 1369 sym_hashes = elf_sym_hashes (input_bfd); 1370 relend = relocs + input_section->reloc_count; 1371 1372 /* Zero the stub area before we start. */ 1373 if (input_section->rawsize != 0 1374 && input_section->size > input_section->rawsize) 1375 memset (contents + input_section->rawsize, 0, 1376 input_section->size - input_section->rawsize); 1377 1378 for (rel = relocs; rel < relend; rel ++) 1379 { 1380 reloc_howto_type *howto; 1381 unsigned long r_symndx; 1382 Elf_Internal_Sym *sym; 1383 asection *sec; 1384 struct elf_link_hash_entry *h; 1385 bfd_vma relocation; 1386 bfd_reloc_status_type r; 1387 const char *name = NULL; 1388 int r_type; 1389 bool undefined_signalled = false; 1390 1391 r_type = ELF64_R_TYPE (rel->r_info); 1392 1393 if (r_type == R_MMIX_GNU_VTINHERIT 1394 || r_type == R_MMIX_GNU_VTENTRY) 1395 continue; 1396 1397 r_symndx = ELF64_R_SYM (rel->r_info); 1398 1399 howto = elf_mmix_howto_table + ELF64_R_TYPE (rel->r_info); 1400 h = NULL; 1401 sym = NULL; 1402 sec = NULL; 1403 1404 if (r_symndx < symtab_hdr->sh_info) 1405 { 1406 sym = local_syms + r_symndx; 1407 sec = local_sections [r_symndx]; 1408 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel); 1409 1410 name = bfd_elf_string_from_elf_section (input_bfd, 1411 symtab_hdr->sh_link, 1412 sym->st_name); 1413 if (name == NULL) 1414 name = bfd_section_name (sec); 1415 } 1416 else 1417 { 1418 bool unresolved_reloc, ignored; 1419 1420 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 1421 r_symndx, symtab_hdr, sym_hashes, 1422 h, sec, relocation, 1423 unresolved_reloc, undefined_signalled, 1424 ignored); 1425 name = h->root.root.string; 1426 } 1427 1428 if (sec != NULL && discarded_section (sec)) 1429 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section, 1430 rel, 1, relend, howto, 0, contents); 1431 1432 if (bfd_link_relocatable (info)) 1433 { 1434 /* This is a relocatable link. For most relocs we don't have to 1435 change anything, unless the reloc is against a section 1436 symbol, in which case we have to adjust according to where 1437 the section symbol winds up in the output section. */ 1438 if (sym != NULL && ELF_ST_TYPE (sym->st_info) == STT_SECTION) 1439 rel->r_addend += sec->output_offset; 1440 1441 /* For PUSHJ stub relocs however, we may need to change the 1442 reloc and the section contents, if the reloc doesn't reach 1443 beyond the end of the output section and previous stubs. 1444 Then we change the section contents to be a PUSHJ to the end 1445 of the input section plus stubs (we can do that without using 1446 a reloc), and then we change the reloc to be a R_MMIX_PUSHJ 1447 at the stub location. */ 1448 if (r_type == R_MMIX_PUSHJ_STUBBABLE) 1449 { 1450 /* We've already checked whether we need a stub; use that 1451 knowledge. */ 1452 if (mmix_elf_section_data (input_section)->pjs.stub_size[pjsno] 1453 != 0) 1454 { 1455 Elf_Internal_Rela relcpy; 1456 1457 if (mmix_elf_section_data (input_section) 1458 ->pjs.stub_size[pjsno] != MAX_PUSHJ_STUB_SIZE) 1459 abort (); 1460 1461 /* There's already a PUSHJ insn there, so just fill in 1462 the offset bits to the stub. */ 1463 if (mmix_final_link_relocate (elf_mmix_howto_table 1464 + R_MMIX_ADDR19, 1465 input_section, 1466 contents, 1467 rel->r_offset, 1468 0, 1469 input_section 1470 ->output_section->vma 1471 + input_section->output_offset 1472 + size 1473 + mmix_elf_section_data (input_section) 1474 ->pjs.stub_offset, 1475 NULL, NULL, NULL) != bfd_reloc_ok) 1476 return false; 1477 1478 /* Put a JMP insn at the stub; it goes with the 1479 R_MMIX_JMP reloc. */ 1480 bfd_put_32 (output_bfd, JMP_INSN_BYTE << 24, 1481 contents 1482 + size 1483 + mmix_elf_section_data (input_section) 1484 ->pjs.stub_offset); 1485 1486 /* Change the reloc to be at the stub, and to a full 1487 R_MMIX_JMP reloc. */ 1488 rel->r_info = ELF64_R_INFO (r_symndx, R_MMIX_JMP); 1489 rel->r_offset 1490 = (size 1491 + mmix_elf_section_data (input_section) 1492 ->pjs.stub_offset); 1493 1494 mmix_elf_section_data (input_section)->pjs.stub_offset 1495 += MAX_PUSHJ_STUB_SIZE; 1496 1497 /* Shift this reloc to the end of the relocs to maintain 1498 the r_offset sorted reloc order. */ 1499 relcpy = *rel; 1500 memmove (rel, rel + 1, (char *) relend - (char *) (rel + 1)); 1501 relend[-1] = relcpy; 1502 1503 /* Back up one reloc, or else we'd skip the next reloc 1504 in turn. */ 1505 rel--; 1506 } 1507 1508 pjsno++; 1509 } 1510 continue; 1511 } 1512 1513 r = mmix_final_link_relocate (howto, input_section, 1514 contents, rel->r_offset, 1515 rel->r_addend, relocation, name, sec, NULL); 1516 1517 if (r != bfd_reloc_ok) 1518 { 1519 const char * msg = (const char *) NULL; 1520 1521 switch (r) 1522 { 1523 case bfd_reloc_overflow: 1524 info->callbacks->reloc_overflow 1525 (info, (h ? &h->root : NULL), name, howto->name, 1526 (bfd_vma) 0, input_bfd, input_section, rel->r_offset); 1527 break; 1528 1529 case bfd_reloc_undefined: 1530 /* We may have sent this message above. */ 1531 if (! undefined_signalled) 1532 info->callbacks->undefined_symbol 1533 (info, name, input_bfd, input_section, rel->r_offset, true); 1534 undefined_signalled = true; 1535 break; 1536 1537 case bfd_reloc_outofrange: 1538 msg = _("internal error: out of range error"); 1539 break; 1540 1541 case bfd_reloc_notsupported: 1542 msg = _("internal error: unsupported relocation error"); 1543 break; 1544 1545 case bfd_reloc_dangerous: 1546 msg = _("internal error: dangerous relocation"); 1547 break; 1548 1549 default: 1550 msg = _("internal error: unknown error"); 1551 break; 1552 } 1553 1554 if (msg) 1555 (*info->callbacks->warning) (info, msg, name, input_bfd, 1556 input_section, rel->r_offset); 1557 } 1558 } 1559 1560 return true; 1561 } 1562 1563 /* Perform a single relocation. By default we use the standard BFD 1565 routines. A few relocs we have to do ourselves. */ 1566 1567 static bfd_reloc_status_type 1568 mmix_final_link_relocate (reloc_howto_type *howto, asection *input_section, 1569 bfd_byte *contents, bfd_vma r_offset, 1570 bfd_signed_vma r_addend, bfd_vma relocation, 1571 const char *symname, asection *symsec, 1572 char **error_message) 1573 { 1574 bfd_reloc_status_type r = bfd_reloc_ok; 1575 bfd_vma addr 1576 = (input_section->output_section->vma 1577 + input_section->output_offset 1578 + r_offset); 1579 bfd_signed_vma srel 1580 = (bfd_signed_vma) relocation + r_addend; 1581 1582 switch (howto->type) 1583 { 1584 /* All these are PC-relative. */ 1585 case R_MMIX_PUSHJ_STUBBABLE: 1586 case R_MMIX_PUSHJ: 1587 case R_MMIX_CBRANCH: 1588 case R_MMIX_ADDR19: 1589 case R_MMIX_GETA: 1590 case R_MMIX_ADDR27: 1591 case R_MMIX_JMP: 1592 contents += r_offset; 1593 1594 srel -= (input_section->output_section->vma 1595 + input_section->output_offset 1596 + r_offset); 1597 1598 r = mmix_elf_perform_relocation (input_section, howto, contents, 1599 addr, srel, error_message); 1600 break; 1601 1602 case R_MMIX_BASE_PLUS_OFFSET: 1603 if (symsec == NULL) 1604 return bfd_reloc_undefined; 1605 1606 /* Check that we're not relocating against a register symbol. */ 1607 if (strcmp (bfd_section_name (symsec), 1608 MMIX_REG_CONTENTS_SECTION_NAME) == 0 1609 || strcmp (bfd_section_name (symsec), 1610 MMIX_REG_SECTION_NAME) == 0) 1611 { 1612 /* Note: This is separated out into two messages in order 1613 to ease the translation into other languages. */ 1614 if (symname == NULL || *symname == 0) 1615 _bfd_error_handler 1616 /* xgettext:c-format */ 1617 (_("%pB: base-plus-offset relocation against register symbol:" 1618 " (unknown) in %pA"), 1619 input_section->owner, symsec); 1620 else 1621 _bfd_error_handler 1622 /* xgettext:c-format */ 1623 (_("%pB: base-plus-offset relocation against register symbol:" 1624 " %s in %pA"), 1625 input_section->owner, symname, symsec); 1626 return bfd_reloc_overflow; 1627 } 1628 goto do_mmix_reloc; 1629 1630 case R_MMIX_REG_OR_BYTE: 1631 case R_MMIX_REG: 1632 /* For now, we handle these alike. They must refer to an register 1633 symbol, which is either relative to the register section and in 1634 the range 0..255, or is in the register contents section with vma 1635 regno * 8. */ 1636 1637 /* FIXME: A better way to check for reg contents section? 1638 FIXME: Postpone section->scaling to mmix_elf_perform_relocation? */ 1639 if (symsec == NULL) 1640 return bfd_reloc_undefined; 1641 1642 if (strcmp (bfd_section_name (symsec), 1643 MMIX_REG_CONTENTS_SECTION_NAME) == 0) 1644 { 1645 if ((srel & 7) != 0 || srel < 32*8 || srel > 255*8) 1646 { 1647 /* The bfd_reloc_outofrange return value, though intuitively 1648 a better value, will not get us an error. */ 1649 return bfd_reloc_overflow; 1650 } 1651 srel /= 8; 1652 } 1653 else if (strcmp (bfd_section_name (symsec), 1654 MMIX_REG_SECTION_NAME) == 0) 1655 { 1656 if (srel < 0 || srel > 255) 1657 /* The bfd_reloc_outofrange return value, though intuitively a 1658 better value, will not get us an error. */ 1659 return bfd_reloc_overflow; 1660 } 1661 else 1662 { 1663 /* Note: This is separated out into two messages in order 1664 to ease the translation into other languages. */ 1665 if (symname == NULL || *symname == 0) 1666 _bfd_error_handler 1667 /* xgettext:c-format */ 1668 (_("%pB: register relocation against non-register symbol:" 1669 " (unknown) in %pA"), 1670 input_section->owner, symsec); 1671 else 1672 _bfd_error_handler 1673 /* xgettext:c-format */ 1674 (_("%pB: register relocation against non-register symbol:" 1675 " %s in %pA"), 1676 input_section->owner, symname, symsec); 1677 1678 /* The bfd_reloc_outofrange return value, though intuitively a 1679 better value, will not get us an error. */ 1680 return bfd_reloc_overflow; 1681 } 1682 do_mmix_reloc: 1683 contents += r_offset; 1684 r = mmix_elf_perform_relocation (input_section, howto, contents, 1685 addr, srel, error_message); 1686 break; 1687 1688 case R_MMIX_LOCAL: 1689 /* This isn't a real relocation, it's just an assertion that the 1690 final relocation value corresponds to a local register. We 1691 ignore the actual relocation; nothing is changed. */ 1692 { 1693 asection *regsec 1694 = bfd_get_section_by_name (input_section->output_section->owner, 1695 MMIX_REG_CONTENTS_SECTION_NAME); 1696 bfd_vma first_global; 1697 1698 /* Check that this is an absolute value, or a reference to the 1699 register contents section or the register (symbol) section. 1700 Absolute numbers can get here as undefined section. Undefined 1701 symbols are signalled elsewhere, so there's no conflict in us 1702 accidentally handling it. */ 1703 if (!bfd_is_abs_section (symsec) 1704 && !bfd_is_und_section (symsec) 1705 && strcmp (bfd_section_name (symsec), 1706 MMIX_REG_CONTENTS_SECTION_NAME) != 0 1707 && strcmp (bfd_section_name (symsec), 1708 MMIX_REG_SECTION_NAME) != 0) 1709 { 1710 _bfd_error_handler 1711 (_("%pB: directive LOCAL valid only with a register or absolute value"), 1712 input_section->owner); 1713 1714 return bfd_reloc_overflow; 1715 } 1716 1717 /* If we don't have a register contents section, then $255 is the 1718 first global register. */ 1719 if (regsec == NULL) 1720 first_global = 255; 1721 else 1722 { 1723 first_global = bfd_section_vma (regsec) / 8; 1724 if (strcmp (bfd_section_name (symsec), 1725 MMIX_REG_CONTENTS_SECTION_NAME) == 0) 1726 { 1727 if ((srel & 7) != 0 || srel < 32*8 || srel > 255*8) 1728 /* The bfd_reloc_outofrange return value, though 1729 intuitively a better value, will not get us an error. */ 1730 return bfd_reloc_overflow; 1731 srel /= 8; 1732 } 1733 } 1734 1735 if ((bfd_vma) srel >= first_global) 1736 { 1737 /* FIXME: Better error message. */ 1738 _bfd_error_handler 1739 /* xgettext:c-format */ 1740 (_("%pB: LOCAL directive: " 1741 "register $%" PRId64 " is not a local register;" 1742 " first global register is $%" PRId64), 1743 input_section->owner, (int64_t) srel, (int64_t) first_global); 1744 1745 return bfd_reloc_overflow; 1746 } 1747 } 1748 r = bfd_reloc_ok; 1749 break; 1750 1751 default: 1752 r = _bfd_final_link_relocate (howto, input_section->owner, input_section, 1753 contents, r_offset, 1754 relocation, r_addend); 1755 } 1756 1757 return r; 1758 } 1759 1760 /* Return the section that should be marked against GC for a given 1762 relocation. */ 1763 1764 static asection * 1765 mmix_elf_gc_mark_hook (asection *sec, 1766 struct bfd_link_info *info, 1767 Elf_Internal_Rela *rel, 1768 struct elf_link_hash_entry *h, 1769 Elf_Internal_Sym *sym) 1770 { 1771 if (h != NULL) 1772 switch (ELF64_R_TYPE (rel->r_info)) 1773 { 1774 case R_MMIX_GNU_VTINHERIT: 1775 case R_MMIX_GNU_VTENTRY: 1776 return NULL; 1777 } 1778 1779 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 1780 } 1781 1782 /* Sort register relocs to come before expanding relocs. */ 1784 1785 static int 1786 mmix_elf_sort_relocs (const void * p1, const void * p2) 1787 { 1788 const Elf_Internal_Rela *r1 = (const Elf_Internal_Rela *) p1; 1789 const Elf_Internal_Rela *r2 = (const Elf_Internal_Rela *) p2; 1790 int r1_is_reg, r2_is_reg; 1791 1792 /* Sort primarily on r_offset & ~3, so relocs are done to consecutive 1793 insns. */ 1794 if ((r1->r_offset & ~(bfd_vma) 3) > (r2->r_offset & ~(bfd_vma) 3)) 1795 return 1; 1796 else if ((r1->r_offset & ~(bfd_vma) 3) < (r2->r_offset & ~(bfd_vma) 3)) 1797 return -1; 1798 1799 r1_is_reg 1800 = (ELF64_R_TYPE (r1->r_info) == R_MMIX_REG_OR_BYTE 1801 || ELF64_R_TYPE (r1->r_info) == R_MMIX_REG); 1802 r2_is_reg 1803 = (ELF64_R_TYPE (r2->r_info) == R_MMIX_REG_OR_BYTE 1804 || ELF64_R_TYPE (r2->r_info) == R_MMIX_REG); 1805 if (r1_is_reg != r2_is_reg) 1806 return r2_is_reg - r1_is_reg; 1807 1808 /* Neither or both are register relocs. Then sort on full offset. */ 1809 if (r1->r_offset > r2->r_offset) 1810 return 1; 1811 else if (r1->r_offset < r2->r_offset) 1812 return -1; 1813 return 0; 1814 } 1815 1816 /* Subset of mmix_elf_check_relocs, common to ELF and mmo linking. */ 1817 1818 static bool 1819 mmix_elf_check_common_relocs (bfd *abfd, 1820 struct bfd_link_info *info, 1821 asection *sec, 1822 const Elf_Internal_Rela *relocs) 1823 { 1824 bfd *bpo_greg_owner = NULL; 1825 asection *allocated_gregs_section = NULL; 1826 struct bpo_greg_section_info *gregdata = NULL; 1827 struct bpo_reloc_section_info *bpodata = NULL; 1828 const Elf_Internal_Rela *rel; 1829 const Elf_Internal_Rela *rel_end; 1830 1831 /* We currently have to abuse this COFF-specific member, since there's 1832 no target-machine-dedicated member. There's no alternative outside 1833 the bfd_link_info struct; we can't specialize a hash-table since 1834 they're different between ELF and mmo. */ 1835 bpo_greg_owner = (bfd *) info->base_file; 1836 1837 rel_end = relocs + sec->reloc_count; 1838 for (rel = relocs; rel < rel_end; rel++) 1839 { 1840 switch (ELF64_R_TYPE (rel->r_info)) 1841 { 1842 /* This relocation causes a GREG allocation. We need to count 1843 them, and we need to create a section for them, so we need an 1844 object to fake as the owner of that section. We can't use 1845 the ELF dynobj for this, since the ELF bits assume lots of 1846 DSO-related stuff if that member is non-NULL. */ 1847 case R_MMIX_BASE_PLUS_OFFSET: 1848 /* We don't do anything with this reloc for a relocatable link. */ 1849 if (bfd_link_relocatable (info)) 1850 break; 1851 1852 if (bpo_greg_owner == NULL) 1853 { 1854 bpo_greg_owner = abfd; 1855 info->base_file = bpo_greg_owner; 1856 } 1857 1858 if (allocated_gregs_section == NULL) 1859 allocated_gregs_section 1860 = bfd_get_section_by_name (bpo_greg_owner, 1861 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 1862 1863 if (allocated_gregs_section == NULL) 1864 { 1865 allocated_gregs_section 1866 = bfd_make_section_with_flags (bpo_greg_owner, 1867 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME, 1868 (SEC_HAS_CONTENTS 1869 | SEC_IN_MEMORY 1870 | SEC_LINKER_CREATED)); 1871 /* Setting both SEC_ALLOC and SEC_LOAD means the section is 1872 treated like any other section, and we'd get errors for 1873 address overlap with the text section. Let's set none of 1874 those flags, as that is what currently happens for usual 1875 GREG allocations, and that works. */ 1876 if (allocated_gregs_section == NULL 1877 || !bfd_set_section_alignment (allocated_gregs_section, 3)) 1878 return false; 1879 1880 gregdata = (struct bpo_greg_section_info *) 1881 bfd_zalloc (bpo_greg_owner, sizeof (struct bpo_greg_section_info)); 1882 if (gregdata == NULL) 1883 return false; 1884 mmix_elf_section_data (allocated_gregs_section)->bpo.greg 1885 = gregdata; 1886 } 1887 else if (gregdata == NULL) 1888 gregdata 1889 = mmix_elf_section_data (allocated_gregs_section)->bpo.greg; 1890 1891 /* Get ourselves some auxiliary info for the BPO-relocs. */ 1892 if (bpodata == NULL) 1893 { 1894 /* No use doing a separate iteration pass to find the upper 1895 limit - just use the number of relocs. */ 1896 bpodata = (struct bpo_reloc_section_info *) 1897 bfd_alloc (bpo_greg_owner, 1898 sizeof (struct bpo_reloc_section_info) 1899 * (sec->reloc_count + 1)); 1900 if (bpodata == NULL) 1901 return false; 1902 mmix_elf_section_data (sec)->bpo.reloc = bpodata; 1903 bpodata->first_base_plus_offset_reloc 1904 = bpodata->bpo_index 1905 = gregdata->n_max_bpo_relocs; 1906 bpodata->bpo_greg_section 1907 = allocated_gregs_section; 1908 bpodata->n_bpo_relocs_this_section = 0; 1909 } 1910 1911 bpodata->n_bpo_relocs_this_section++; 1912 gregdata->n_max_bpo_relocs++; 1913 1914 /* We don't get another chance to set this before GC; we've not 1915 set up any hook that runs before GC. */ 1916 gregdata->n_bpo_relocs 1917 = gregdata->n_max_bpo_relocs; 1918 break; 1919 1920 case R_MMIX_PUSHJ_STUBBABLE: 1921 mmix_elf_section_data (sec)->pjs.n_pushj_relocs++; 1922 break; 1923 } 1924 } 1925 1926 /* Allocate per-reloc stub storage and initialize it to the max stub 1927 size. */ 1928 if (mmix_elf_section_data (sec)->pjs.n_pushj_relocs != 0) 1929 { 1930 size_t i; 1931 1932 mmix_elf_section_data (sec)->pjs.stub_size 1933 = bfd_alloc (abfd, mmix_elf_section_data (sec)->pjs.n_pushj_relocs 1934 * sizeof (mmix_elf_section_data (sec) 1935 ->pjs.stub_size[0])); 1936 if (mmix_elf_section_data (sec)->pjs.stub_size == NULL) 1937 return false; 1938 1939 for (i = 0; i < mmix_elf_section_data (sec)->pjs.n_pushj_relocs; i++) 1940 mmix_elf_section_data (sec)->pjs.stub_size[i] = MAX_PUSHJ_STUB_SIZE; 1941 } 1942 1943 return true; 1944 } 1945 1946 /* Look through the relocs for a section during the first phase. */ 1947 1948 static bool 1949 mmix_elf_check_relocs (bfd *abfd, 1950 struct bfd_link_info *info, 1951 asection *sec, 1952 const Elf_Internal_Rela *relocs) 1953 { 1954 Elf_Internal_Shdr *symtab_hdr; 1955 struct elf_link_hash_entry **sym_hashes; 1956 const Elf_Internal_Rela *rel; 1957 const Elf_Internal_Rela *rel_end; 1958 1959 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 1960 sym_hashes = elf_sym_hashes (abfd); 1961 1962 /* First we sort the relocs so that any register relocs come before 1963 expansion-relocs to the same insn. FIXME: Not done for mmo. */ 1964 qsort ((void *) relocs, sec->reloc_count, sizeof (Elf_Internal_Rela), 1965 mmix_elf_sort_relocs); 1966 1967 /* Do the common part. */ 1968 if (!mmix_elf_check_common_relocs (abfd, info, sec, relocs)) 1969 return false; 1970 1971 if (bfd_link_relocatable (info)) 1972 return true; 1973 1974 rel_end = relocs + sec->reloc_count; 1975 for (rel = relocs; rel < rel_end; rel++) 1976 { 1977 struct elf_link_hash_entry *h; 1978 unsigned long r_symndx; 1979 1980 r_symndx = ELF64_R_SYM (rel->r_info); 1981 if (r_symndx < symtab_hdr->sh_info) 1982 h = NULL; 1983 else 1984 { 1985 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1986 while (h->root.type == bfd_link_hash_indirect 1987 || h->root.type == bfd_link_hash_warning) 1988 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1989 } 1990 1991 switch (ELF64_R_TYPE (rel->r_info)) 1992 { 1993 /* This relocation describes the C++ object vtable hierarchy. 1994 Reconstruct it for later use during GC. */ 1995 case R_MMIX_GNU_VTINHERIT: 1996 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 1997 return false; 1998 break; 1999 2000 /* This relocation describes which C++ vtable entries are actually 2001 used. Record for later use during GC. */ 2002 case R_MMIX_GNU_VTENTRY: 2003 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend)) 2004 return false; 2005 break; 2006 } 2007 } 2008 2009 return true; 2010 } 2011 2012 /* Wrapper for mmix_elf_check_common_relocs, called when linking to mmo. 2013 Copied from elf_link_add_object_symbols. */ 2014 2015 bool 2016 _bfd_mmix_check_all_relocs (bfd *abfd, struct bfd_link_info *info) 2017 { 2018 asection *o; 2019 2020 for (o = abfd->sections; o != NULL; o = o->next) 2021 { 2022 Elf_Internal_Rela *internal_relocs; 2023 bool ok; 2024 2025 if ((o->flags & SEC_RELOC) == 0 2026 || o->reloc_count == 0 2027 || ((info->strip == strip_all || info->strip == strip_debugger) 2028 && (o->flags & SEC_DEBUGGING) != 0) 2029 || bfd_is_abs_section (o->output_section)) 2030 continue; 2031 2032 internal_relocs 2033 = _bfd_elf_link_read_relocs (abfd, o, NULL, 2034 (Elf_Internal_Rela *) NULL, 2035 info->keep_memory); 2036 if (internal_relocs == NULL) 2037 return false; 2038 2039 ok = mmix_elf_check_common_relocs (abfd, info, o, internal_relocs); 2040 2041 if (! info->keep_memory) 2042 free (internal_relocs); 2043 2044 if (! ok) 2045 return false; 2046 } 2047 2048 return true; 2049 } 2050 2051 /* Change symbols relative to the reg contents section to instead be to 2053 the register section, and scale them down to correspond to the register 2054 number. */ 2055 2056 static int 2057 mmix_elf_link_output_symbol_hook (struct bfd_link_info *info ATTRIBUTE_UNUSED, 2058 const char *name ATTRIBUTE_UNUSED, 2059 Elf_Internal_Sym *sym, 2060 asection *input_sec, 2061 struct elf_link_hash_entry *h ATTRIBUTE_UNUSED) 2062 { 2063 if (input_sec != NULL 2064 && input_sec->name != NULL 2065 && ELF_ST_TYPE (sym->st_info) != STT_SECTION 2066 && strcmp (input_sec->name, MMIX_REG_CONTENTS_SECTION_NAME) == 0) 2067 { 2068 sym->st_value /= 8; 2069 sym->st_shndx = SHN_REGISTER; 2070 } 2071 2072 return 1; 2073 } 2074 2075 /* We fake a register section that holds values that are register numbers. 2076 Having a SHN_REGISTER and register section translates better to other 2077 formats (e.g. mmo) than for example a STT_REGISTER attribute. 2078 This section faking is based on a construct in elf32-mips.c. */ 2079 static asection mmix_elf_reg_section; 2080 static const asymbol mmix_elf_reg_section_symbol = 2081 GLOBAL_SYM_INIT (MMIX_REG_SECTION_NAME, &mmix_elf_reg_section); 2082 static asection mmix_elf_reg_section = 2083 BFD_FAKE_SECTION (mmix_elf_reg_section, &mmix_elf_reg_section_symbol, 2084 MMIX_REG_SECTION_NAME, 0, SEC_NO_FLAGS); 2085 2086 /* Handle the special section numbers that a symbol may use. */ 2087 2088 void 2089 mmix_elf_symbol_processing (bfd *abfd ATTRIBUTE_UNUSED, asymbol *asym) 2090 { 2091 elf_symbol_type *elfsym; 2092 2093 elfsym = (elf_symbol_type *) asym; 2094 switch (elfsym->internal_elf_sym.st_shndx) 2095 { 2096 case SHN_REGISTER: 2097 asym->section = &mmix_elf_reg_section; 2098 break; 2099 2100 default: 2101 break; 2102 } 2103 } 2104 2105 /* Given a BFD section, try to locate the corresponding ELF section 2106 index. */ 2107 2108 static bool 2109 mmix_elf_section_from_bfd_section (bfd * abfd ATTRIBUTE_UNUSED, 2110 asection * sec, 2111 int * retval) 2112 { 2113 if (strcmp (bfd_section_name (sec), MMIX_REG_SECTION_NAME) == 0) 2114 *retval = SHN_REGISTER; 2115 else 2116 return false; 2117 2118 return true; 2119 } 2120 2121 /* Hook called by the linker routine which adds symbols from an object 2122 file. We must handle the special SHN_REGISTER section number here. 2123 2124 We also check that we only have *one* each of the section-start 2125 symbols, since otherwise having two with the same value would cause 2126 them to be "merged", but with the contents serialized. */ 2127 2128 static bool 2129 mmix_elf_add_symbol_hook (bfd *abfd, 2130 struct bfd_link_info *info ATTRIBUTE_UNUSED, 2131 Elf_Internal_Sym *sym, 2132 const char **namep ATTRIBUTE_UNUSED, 2133 flagword *flagsp ATTRIBUTE_UNUSED, 2134 asection **secp, 2135 bfd_vma *valp ATTRIBUTE_UNUSED) 2136 { 2137 if (sym->st_shndx == SHN_REGISTER) 2138 { 2139 *secp = bfd_make_section_old_way (abfd, MMIX_REG_SECTION_NAME); 2140 (*secp)->flags |= SEC_LINKER_CREATED; 2141 } 2142 else if ((*namep)[0] == '_' && (*namep)[1] == '_' && (*namep)[2] == '.' 2143 && startswith (*namep, MMIX_LOC_SECTION_START_SYMBOL_PREFIX)) 2144 { 2145 /* See if we have another one. */ 2146 struct bfd_link_hash_entry *h = bfd_link_hash_lookup (info->hash, 2147 *namep, 2148 false, 2149 false, 2150 false); 2151 2152 if (h != NULL && h->type != bfd_link_hash_undefined) 2153 { 2154 /* How do we get the asymbol (or really: the filename) from h? 2155 h->u.def.section->owner is NULL. */ 2156 _bfd_error_handler 2157 /* xgettext:c-format */ 2158 (_("%pB: error: multiple definition of `%s'; start of %s " 2159 "is set in a earlier linked file"), 2160 abfd, *namep, 2161 *namep + strlen (MMIX_LOC_SECTION_START_SYMBOL_PREFIX)); 2162 bfd_set_error (bfd_error_bad_value); 2163 return false; 2164 } 2165 } 2166 2167 return true; 2168 } 2169 2170 /* We consider symbols matching "L.*:[0-9]+" to be local symbols. */ 2171 2172 static bool 2173 mmix_elf_is_local_label_name (bfd *abfd, const char *name) 2174 { 2175 const char *colpos; 2176 int digits; 2177 2178 /* Also include the default local-label definition. */ 2179 if (_bfd_elf_is_local_label_name (abfd, name)) 2180 return true; 2181 2182 if (*name != 'L') 2183 return false; 2184 2185 /* If there's no ":", or more than one, it's not a local symbol. */ 2186 colpos = strchr (name, ':'); 2187 if (colpos == NULL || strchr (colpos + 1, ':') != NULL) 2188 return false; 2189 2190 /* Check that there are remaining characters and that they are digits. */ 2191 if (colpos[1] == 0) 2192 return false; 2193 2194 digits = strspn (colpos + 1, "0123456789"); 2195 return digits != 0 && colpos[1 + digits] == 0; 2196 } 2197 2198 /* We get rid of the register section here. */ 2199 2200 bool 2201 mmix_elf_final_link (bfd *abfd, struct bfd_link_info *info) 2202 { 2203 /* We never output a register section, though we create one for 2204 temporary measures. Check that nobody entered contents into it. */ 2205 asection *reg_section; 2206 2207 reg_section = bfd_get_section_by_name (abfd, MMIX_REG_SECTION_NAME); 2208 2209 if (reg_section != NULL) 2210 { 2211 /* FIXME: Pass error state gracefully. */ 2212 if (bfd_section_flags (reg_section) & SEC_HAS_CONTENTS) 2213 _bfd_abort (__FILE__, __LINE__, _("register section has contents\n")); 2214 2215 /* Really remove the section, if it hasn't already been done. */ 2216 if (!bfd_section_removed_from_list (abfd, reg_section)) 2217 { 2218 bfd_section_list_remove (abfd, reg_section); 2219 --abfd->section_count; 2220 } 2221 } 2222 2223 if (! bfd_elf_final_link (abfd, info)) 2224 return false; 2225 2226 /* Since this section is marked SEC_LINKER_CREATED, it isn't output by 2227 the regular linker machinery. We do it here, like other targets with 2228 special sections. */ 2229 if (info->base_file != NULL) 2230 { 2231 asection *greg_section 2232 = bfd_get_section_by_name ((bfd *) info->base_file, 2233 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2234 if (!bfd_set_section_contents (abfd, 2235 greg_section->output_section, 2236 greg_section->contents, 2237 (file_ptr) greg_section->output_offset, 2238 greg_section->size)) 2239 return false; 2240 } 2241 return true; 2242 } 2243 2244 /* We need to include the maximum size of PUSHJ-stubs in the initial 2245 section size. This is expected to shrink during linker relaxation. */ 2246 2247 static void 2248 mmix_set_relaxable_size (bfd *abfd ATTRIBUTE_UNUSED, 2249 asection *sec, 2250 void *ptr) 2251 { 2252 struct bfd_link_info *info = ptr; 2253 2254 /* Make sure we only do this for section where we know we want this, 2255 otherwise we might end up resetting the size of COMMONs. */ 2256 if (mmix_elf_section_data (sec)->pjs.n_pushj_relocs == 0) 2257 return; 2258 2259 sec->rawsize = sec->size; 2260 sec->size += (mmix_elf_section_data (sec)->pjs.n_pushj_relocs 2261 * MAX_PUSHJ_STUB_SIZE); 2262 2263 /* For use in relocatable link, we start with a max stubs size. See 2264 mmix_elf_relax_section. */ 2265 if (bfd_link_relocatable (info) && sec->output_section) 2266 mmix_elf_section_data (sec->output_section)->pjs.stubs_size_sum 2267 += (mmix_elf_section_data (sec)->pjs.n_pushj_relocs 2268 * MAX_PUSHJ_STUB_SIZE); 2269 } 2270 2271 /* Initialize stuff for the linker-generated GREGs to match 2272 R_MMIX_BASE_PLUS_OFFSET relocs seen by the linker. */ 2273 2274 bool 2275 _bfd_mmix_before_linker_allocation (bfd *abfd ATTRIBUTE_UNUSED, 2276 struct bfd_link_info *info) 2277 { 2278 asection *bpo_gregs_section; 2279 bfd *bpo_greg_owner; 2280 struct bpo_greg_section_info *gregdata; 2281 size_t n_gregs; 2282 bfd_vma gregs_size; 2283 size_t i; 2284 size_t *bpo_reloc_indexes; 2285 bfd *ibfd; 2286 2287 /* Set the initial size of sections. */ 2288 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next) 2289 bfd_map_over_sections (ibfd, mmix_set_relaxable_size, info); 2290 2291 /* The bpo_greg_owner bfd is supposed to have been set by 2292 mmix_elf_check_relocs when the first R_MMIX_BASE_PLUS_OFFSET is seen. 2293 If there is no such object, there was no R_MMIX_BASE_PLUS_OFFSET. */ 2294 bpo_greg_owner = (bfd *) info->base_file; 2295 if (bpo_greg_owner == NULL) 2296 return true; 2297 2298 bpo_gregs_section 2299 = bfd_get_section_by_name (bpo_greg_owner, 2300 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2301 2302 if (bpo_gregs_section == NULL) 2303 return true; 2304 2305 /* We use the target-data handle in the ELF section data. */ 2306 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2307 if (gregdata == NULL) 2308 return false; 2309 2310 n_gregs = gregdata->n_bpo_relocs; 2311 gregdata->n_allocated_bpo_gregs = n_gregs; 2312 2313 /* When this reaches zero during relaxation, all entries have been 2314 filled in and the size of the linker gregs can be calculated. */ 2315 gregdata->n_remaining_bpo_relocs_this_relaxation_round = n_gregs; 2316 2317 /* Set the zeroth-order estimate for the GREGs size. */ 2318 gregs_size = n_gregs * 8; 2319 2320 if (!bfd_set_section_size (bpo_gregs_section, gregs_size)) 2321 return false; 2322 2323 /* Allocate and set up the GREG arrays. They're filled in at relaxation 2324 time. Note that we must use the max number ever noted for the array, 2325 since the index numbers were created before GC. */ 2326 gregdata->reloc_request 2327 = bfd_zalloc (bpo_greg_owner, 2328 sizeof (struct bpo_reloc_request) 2329 * gregdata->n_max_bpo_relocs); 2330 2331 gregdata->bpo_reloc_indexes 2332 = bpo_reloc_indexes 2333 = bfd_alloc (bpo_greg_owner, 2334 gregdata->n_max_bpo_relocs 2335 * sizeof (size_t)); 2336 if (bpo_reloc_indexes == NULL) 2337 return false; 2338 2339 /* The default order is an identity mapping. */ 2340 for (i = 0; i < gregdata->n_max_bpo_relocs; i++) 2341 { 2342 bpo_reloc_indexes[i] = i; 2343 gregdata->reloc_request[i].bpo_reloc_no = i; 2344 } 2345 2346 return true; 2347 } 2348 2349 /* Fill in contents in the linker allocated gregs. Everything is 2351 calculated at this point; we just move the contents into place here. */ 2352 2353 bool 2354 _bfd_mmix_after_linker_allocation (bfd *abfd ATTRIBUTE_UNUSED, 2355 struct bfd_link_info *link_info) 2356 { 2357 asection *bpo_gregs_section; 2358 bfd *bpo_greg_owner; 2359 struct bpo_greg_section_info *gregdata; 2360 size_t n_gregs; 2361 size_t i, j; 2362 size_t lastreg; 2363 bfd_byte *contents; 2364 2365 /* The bpo_greg_owner bfd is supposed to have been set by mmix_elf_check_relocs 2366 when the first R_MMIX_BASE_PLUS_OFFSET is seen. If there is no such 2367 object, there was no R_MMIX_BASE_PLUS_OFFSET. */ 2368 bpo_greg_owner = (bfd *) link_info->base_file; 2369 if (bpo_greg_owner == NULL) 2370 return true; 2371 2372 bpo_gregs_section 2373 = bfd_get_section_by_name (bpo_greg_owner, 2374 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2375 2376 /* This can't happen without DSO handling. When DSOs are handled 2377 without any R_MMIX_BASE_PLUS_OFFSET seen, there will be no such 2378 section. */ 2379 if (bpo_gregs_section == NULL) 2380 return true; 2381 2382 /* We use the target-data handle in the ELF section data. */ 2383 2384 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2385 if (gregdata == NULL) 2386 return false; 2387 2388 n_gregs = gregdata->n_allocated_bpo_gregs; 2389 2390 bpo_gregs_section->contents 2391 = contents = bfd_alloc (bpo_greg_owner, bpo_gregs_section->size); 2392 if (contents == NULL) 2393 return false; 2394 bpo_gregs_section->alloced = 1; 2395 2396 /* Sanity check: If these numbers mismatch, some relocation has not been 2397 accounted for and the rest of gregdata is probably inconsistent. 2398 It's a bug, but it's more helpful to identify it than segfaulting 2399 below. */ 2400 if (gregdata->n_remaining_bpo_relocs_this_relaxation_round 2401 != gregdata->n_bpo_relocs) 2402 { 2403 _bfd_error_handler 2404 /* xgettext:c-format */ 2405 (_("internal inconsistency: remaining %lu != max %lu;" 2406 " please report this bug"), 2407 (unsigned long) gregdata->n_remaining_bpo_relocs_this_relaxation_round, 2408 (unsigned long) gregdata->n_bpo_relocs); 2409 return false; 2410 } 2411 2412 for (lastreg = 255, i = 0, j = 0; j < n_gregs; i++) 2413 if (gregdata->reloc_request[i].regindex != lastreg) 2414 { 2415 bfd_put_64 (bpo_greg_owner, gregdata->reloc_request[i].value, 2416 contents + j * 8); 2417 lastreg = gregdata->reloc_request[i].regindex; 2418 j++; 2419 } 2420 2421 return true; 2422 } 2423 2424 /* Sort valid relocs to come before non-valid relocs, then on increasing 2425 value. */ 2426 2427 static int 2428 bpo_reloc_request_sort_fn (const void * p1, const void * p2) 2429 { 2430 const struct bpo_reloc_request *r1 = (const struct bpo_reloc_request *) p1; 2431 const struct bpo_reloc_request *r2 = (const struct bpo_reloc_request *) p2; 2432 2433 /* Primary function is validity; non-valid relocs sorted after valid 2434 ones. */ 2435 if (r1->valid != r2->valid) 2436 return r2->valid - r1->valid; 2437 2438 /* Then sort on value. Don't simplify and return just the difference of 2439 the values: the upper bits of the 64-bit value would be truncated on 2440 a host with 32-bit ints. */ 2441 if (r1->value != r2->value) 2442 return r1->value > r2->value ? 1 : -1; 2443 2444 /* As a last re-sort, use the relocation number, so we get a stable 2445 sort. The *addresses* aren't stable since items are swapped during 2446 sorting. It depends on the qsort implementation if this actually 2447 happens. */ 2448 return r1->bpo_reloc_no > r2->bpo_reloc_no 2449 ? 1 : (r1->bpo_reloc_no < r2->bpo_reloc_no ? -1 : 0); 2450 } 2451 2452 /* For debug use only. Dumps the global register allocations resulting 2453 from base-plus-offset relocs. */ 2454 2455 void 2456 mmix_dump_bpo_gregs (struct bfd_link_info *link_info, 2457 void (*pf) (const char *fmt, ...)) 2458 { 2459 bfd *bpo_greg_owner; 2460 asection *bpo_gregs_section; 2461 struct bpo_greg_section_info *gregdata; 2462 unsigned int i; 2463 2464 if (link_info == NULL || link_info->base_file == NULL) 2465 return; 2466 2467 bpo_greg_owner = (bfd *) link_info->base_file; 2468 2469 bpo_gregs_section 2470 = bfd_get_section_by_name (bpo_greg_owner, 2471 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2472 2473 if (bpo_gregs_section == NULL) 2474 return; 2475 2476 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2477 if (gregdata == NULL) 2478 return; 2479 2480 if (pf == NULL) 2481 pf = _bfd_error_handler; 2482 2483 /* These format strings are not translated. They are for debug purposes 2484 only and never displayed to an end user. Should they escape, we 2485 surely want them in original. */ 2486 (*pf) (" n_bpo_relocs: %u\n n_max_bpo_relocs: %u\n n_remain...round: %u\n\ 2487 n_allocated_bpo_gregs: %u\n", gregdata->n_bpo_relocs, 2488 gregdata->n_max_bpo_relocs, 2489 gregdata->n_remaining_bpo_relocs_this_relaxation_round, 2490 gregdata->n_allocated_bpo_gregs); 2491 2492 if (gregdata->reloc_request) 2493 for (i = 0; i < gregdata->n_max_bpo_relocs; i++) 2494 (*pf) ("%4u (%4u)/%4u#%u: 0x%08lx%08lx r: %3u o: %3u\n", 2495 i, 2496 (gregdata->bpo_reloc_indexes != NULL 2497 ? gregdata->bpo_reloc_indexes[i] : (size_t) -1), 2498 gregdata->reloc_request[i].bpo_reloc_no, 2499 gregdata->reloc_request[i].valid, 2500 2501 (unsigned long) (gregdata->reloc_request[i].value >> 32), 2502 (unsigned long) gregdata->reloc_request[i].value, 2503 gregdata->reloc_request[i].regindex, 2504 gregdata->reloc_request[i].offset); 2505 } 2506 2507 /* This links all R_MMIX_BASE_PLUS_OFFSET relocs into a special array, and 2508 when the last such reloc is done, an index-array is sorted according to 2509 the values and iterated over to produce register numbers (indexed by 0 2510 from the first allocated register number) and offsets for use in real 2511 relocation. (N.B.: Relocatable runs are handled, not just punted.) 2512 2513 PUSHJ stub accounting is also done here. 2514 2515 Symbol- and reloc-reading infrastructure copied from elf-m10200.c. */ 2516 2517 static bool 2518 mmix_elf_relax_section (bfd *abfd, 2519 asection *sec, 2520 struct bfd_link_info *link_info, 2521 bool *again) 2522 { 2523 Elf_Internal_Shdr *symtab_hdr; 2524 Elf_Internal_Rela *internal_relocs; 2525 Elf_Internal_Rela *irel, *irelend; 2526 asection *bpo_gregs_section = NULL; 2527 struct bpo_greg_section_info *gregdata; 2528 struct bpo_reloc_section_info *bpodata 2529 = mmix_elf_section_data (sec)->bpo.reloc; 2530 /* The initialization is to quiet compiler warnings. The value is to 2531 spot a missing actual initialization. */ 2532 size_t bpono = (size_t) -1; 2533 size_t pjsno = 0; 2534 size_t pjsno_undefs = 0; 2535 Elf_Internal_Sym *isymbuf = NULL; 2536 bfd_size_type size = sec->rawsize ? sec->rawsize : sec->size; 2537 2538 mmix_elf_section_data (sec)->pjs.stubs_size_sum = 0; 2539 2540 /* Assume nothing changes. */ 2541 *again = false; 2542 2543 /* We don't have to do anything if this section does not have relocs, or 2544 if this is not a code section. */ 2545 if ((sec->flags & SEC_RELOC) == 0 2546 || sec->reloc_count == 0 2547 || (sec->flags & SEC_CODE) == 0 2548 || (sec->flags & SEC_LINKER_CREATED) != 0 2549 /* If no R_MMIX_BASE_PLUS_OFFSET relocs and no PUSHJ-stub relocs, 2550 then nothing to do. */ 2551 || (bpodata == NULL 2552 && mmix_elf_section_data (sec)->pjs.n_pushj_relocs == 0)) 2553 return true; 2554 2555 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 2556 2557 if (bpodata != NULL) 2558 { 2559 bpo_gregs_section = bpodata->bpo_greg_section; 2560 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2561 bpono = bpodata->first_base_plus_offset_reloc; 2562 } 2563 else 2564 gregdata = NULL; 2565 2566 /* Get a copy of the native relocations. */ 2567 internal_relocs 2568 = _bfd_elf_link_read_relocs (abfd, sec, NULL, 2569 (Elf_Internal_Rela *) NULL, 2570 link_info->keep_memory); 2571 if (internal_relocs == NULL) 2572 goto error_return; 2573 2574 /* Walk through them looking for relaxing opportunities. */ 2575 irelend = internal_relocs + sec->reloc_count; 2576 for (irel = internal_relocs; irel < irelend; irel++) 2577 { 2578 bfd_vma symval; 2579 struct elf_link_hash_entry *h = NULL; 2580 2581 /* We only process two relocs. */ 2582 if (ELF64_R_TYPE (irel->r_info) != (int) R_MMIX_BASE_PLUS_OFFSET 2583 && ELF64_R_TYPE (irel->r_info) != (int) R_MMIX_PUSHJ_STUBBABLE) 2584 continue; 2585 2586 /* We process relocs in a distinctly different way when this is a 2587 relocatable link (for one, we don't look at symbols), so we avoid 2588 mixing its code with that for the "normal" relaxation. */ 2589 if (bfd_link_relocatable (link_info)) 2590 { 2591 /* The only transformation in a relocatable link is to generate 2592 a full stub at the location of the stub calculated for the 2593 input section, if the relocated stub location, the end of the 2594 output section plus earlier stubs, cannot be reached. Thus 2595 relocatable linking can only lead to worse code, but it still 2596 works. */ 2597 if (ELF64_R_TYPE (irel->r_info) == R_MMIX_PUSHJ_STUBBABLE) 2598 { 2599 /* If we can reach the end of the output-section and beyond 2600 any current stubs, then we don't need a stub for this 2601 reloc. The relaxed order of output stub allocation may 2602 not exactly match the straightforward order, so we always 2603 assume presence of output stubs, which will allow 2604 relaxation only on relocations indifferent to the 2605 presence of output stub allocations for other relocations 2606 and thus the order of output stub allocation. */ 2607 if (bfd_check_overflow (complain_overflow_signed, 2608 19, 2609 0, 2610 bfd_arch_bits_per_address (abfd), 2611 /* Output-stub location. */ 2612 sec->output_section->rawsize 2613 + (mmix_elf_section_data (sec 2614 ->output_section) 2615 ->pjs.stubs_size_sum) 2616 /* Location of this PUSHJ reloc. */ 2617 - (sec->output_offset + irel->r_offset) 2618 /* Don't count *this* stub twice. */ 2619 - (mmix_elf_section_data (sec) 2620 ->pjs.stub_size[pjsno] 2621 + MAX_PUSHJ_STUB_SIZE)) 2622 == bfd_reloc_ok) 2623 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] = 0; 2624 2625 mmix_elf_section_data (sec)->pjs.stubs_size_sum 2626 += mmix_elf_section_data (sec)->pjs.stub_size[pjsno]; 2627 2628 pjsno++; 2629 } 2630 2631 continue; 2632 } 2633 2634 /* Get the value of the symbol referred to by the reloc. */ 2635 if (ELF64_R_SYM (irel->r_info) < symtab_hdr->sh_info) 2636 { 2637 /* A local symbol. */ 2638 Elf_Internal_Sym *isym; 2639 asection *sym_sec; 2640 2641 /* Read this BFD's local symbols if we haven't already. */ 2642 if (isymbuf == NULL) 2643 { 2644 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents; 2645 if (isymbuf == NULL) 2646 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr, 2647 symtab_hdr->sh_info, 0, 2648 NULL, NULL, NULL); 2649 if (isymbuf == 0) 2650 goto error_return; 2651 } 2652 2653 isym = isymbuf + ELF64_R_SYM (irel->r_info); 2654 if (isym->st_shndx == SHN_UNDEF) 2655 sym_sec = bfd_und_section_ptr; 2656 else if (isym->st_shndx == SHN_ABS) 2657 sym_sec = bfd_abs_section_ptr; 2658 else if (isym->st_shndx == SHN_COMMON) 2659 sym_sec = bfd_com_section_ptr; 2660 else 2661 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx); 2662 symval = (isym->st_value 2663 + sym_sec->output_section->vma 2664 + sym_sec->output_offset); 2665 } 2666 else 2667 { 2668 unsigned long indx; 2669 2670 /* An external symbol. */ 2671 indx = ELF64_R_SYM (irel->r_info) - symtab_hdr->sh_info; 2672 h = elf_sym_hashes (abfd)[indx]; 2673 BFD_ASSERT (h != NULL); 2674 if (h->root.type == bfd_link_hash_undefweak) 2675 /* FIXME: for R_MMIX_PUSHJ_STUBBABLE, there are alternatives to 2676 the canonical value 0 for an unresolved weak symbol to 2677 consider: as the debug-friendly approach, resolve to "abort" 2678 (or a port-specific function), or as the space-friendly 2679 approach resolve to the next instruction (like some other 2680 ports, notably ARM and AArch64). These alternatives require 2681 matching code in mmix_elf_perform_relocation or its caller. */ 2682 symval = 0; 2683 else if (h->root.type == bfd_link_hash_defined 2684 || h->root.type == bfd_link_hash_defweak) 2685 symval = (h->root.u.def.value 2686 + h->root.u.def.section->output_section->vma 2687 + h->root.u.def.section->output_offset); 2688 else 2689 { 2690 /* This appears to be a reference to an undefined symbol. Just 2691 ignore it--it will be caught by the regular reloc processing. 2692 We need to keep BPO reloc accounting consistent, though 2693 else we'll abort instead of emitting an error message. */ 2694 if (ELF64_R_TYPE (irel->r_info) == R_MMIX_BASE_PLUS_OFFSET 2695 && gregdata != NULL) 2696 { 2697 gregdata->n_remaining_bpo_relocs_this_relaxation_round--; 2698 bpono++; 2699 } 2700 2701 /* Similarly, keep accounting consistent for PUSHJ 2702 referring to an undefined symbol. */ 2703 if (ELF64_R_TYPE (irel->r_info) == R_MMIX_PUSHJ_STUBBABLE) 2704 pjsno_undefs++; 2705 continue; 2706 } 2707 } 2708 2709 if (ELF64_R_TYPE (irel->r_info) == (int) R_MMIX_PUSHJ_STUBBABLE) 2710 { 2711 bfd_vma value = symval + irel->r_addend; 2712 bfd_vma dot 2713 = (sec->output_section->vma 2714 + sec->output_offset 2715 + irel->r_offset); 2716 bfd_vma stubaddr 2717 = (sec->output_section->vma 2718 + sec->output_offset 2719 + size 2720 + mmix_elf_section_data (sec)->pjs.stubs_size_sum); 2721 2722 if ((value & 3) == 0 2723 && bfd_check_overflow (complain_overflow_signed, 2724 19, 2725 0, 2726 bfd_arch_bits_per_address (abfd), 2727 value - dot 2728 - (value > dot 2729 ? mmix_elf_section_data (sec) 2730 ->pjs.stub_size[pjsno] 2731 : 0)) 2732 == bfd_reloc_ok) 2733 /* If the reloc fits, no stub is needed. */ 2734 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] = 0; 2735 else 2736 /* Maybe we can get away with just a JMP insn? */ 2737 if ((value & 3) == 0 2738 && bfd_check_overflow (complain_overflow_signed, 2739 27, 2740 0, 2741 bfd_arch_bits_per_address (abfd), 2742 value - stubaddr 2743 - (value > dot 2744 ? mmix_elf_section_data (sec) 2745 ->pjs.stub_size[pjsno] - 4 2746 : 0)) 2747 == bfd_reloc_ok) 2748 /* Yep, account for a stub consisting of a single JMP insn. */ 2749 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] = 4; 2750 else 2751 /* Nope, go for the full insn stub. It doesn't seem useful to 2752 emit the intermediate sizes; those will only be useful for 2753 a >64M program assuming contiguous code. */ 2754 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] 2755 = MAX_PUSHJ_STUB_SIZE; 2756 2757 mmix_elf_section_data (sec)->pjs.stubs_size_sum 2758 += mmix_elf_section_data (sec)->pjs.stub_size[pjsno]; 2759 pjsno++; 2760 continue; 2761 } 2762 2763 /* We're looking at a R_MMIX_BASE_PLUS_OFFSET reloc. */ 2764 2765 gregdata->reloc_request[gregdata->bpo_reloc_indexes[bpono]].value 2766 = symval + irel->r_addend; 2767 gregdata->reloc_request[gregdata->bpo_reloc_indexes[bpono++]].valid = true; 2768 gregdata->n_remaining_bpo_relocs_this_relaxation_round--; 2769 } 2770 2771 /* Check if that was the last BPO-reloc. If so, sort the values and 2772 calculate how many registers we need to cover them. Set the size of 2773 the linker gregs, and if the number of registers changed, indicate 2774 that we need to relax some more because we have more work to do. */ 2775 if (gregdata != NULL 2776 && gregdata->n_remaining_bpo_relocs_this_relaxation_round == 0) 2777 { 2778 size_t i; 2779 bfd_vma prev_base; 2780 size_t regindex; 2781 2782 /* First, reset the remaining relocs for the next round. */ 2783 gregdata->n_remaining_bpo_relocs_this_relaxation_round 2784 = gregdata->n_bpo_relocs; 2785 2786 qsort (gregdata->reloc_request, 2787 gregdata->n_max_bpo_relocs, 2788 sizeof (struct bpo_reloc_request), 2789 bpo_reloc_request_sort_fn); 2790 2791 /* Recalculate indexes. When we find a change (however unlikely 2792 after the initial iteration), we know we need to relax again, 2793 since items in the GREG-array are sorted by increasing value and 2794 stored in the relaxation phase. */ 2795 for (i = 0; i < gregdata->n_max_bpo_relocs; i++) 2796 if (gregdata->bpo_reloc_indexes[gregdata->reloc_request[i].bpo_reloc_no] 2797 != i) 2798 { 2799 gregdata->bpo_reloc_indexes[gregdata->reloc_request[i].bpo_reloc_no] 2800 = i; 2801 *again = true; 2802 } 2803 2804 /* Allocate register numbers (indexing from 0). Stop at the first 2805 non-valid reloc. */ 2806 for (i = 0, regindex = 0, prev_base = gregdata->reloc_request[0].value; 2807 i < gregdata->n_bpo_relocs; 2808 i++) 2809 { 2810 if (gregdata->reloc_request[i].value > prev_base + 255) 2811 { 2812 regindex++; 2813 prev_base = gregdata->reloc_request[i].value; 2814 } 2815 gregdata->reloc_request[i].regindex = regindex; 2816 gregdata->reloc_request[i].offset 2817 = gregdata->reloc_request[i].value - prev_base; 2818 } 2819 2820 /* If it's not the same as the last time, we need to relax again, 2821 because the size of the section has changed. I'm not sure we 2822 actually need to do any adjustments since the shrinking happens 2823 at the start of this section, but better safe than sorry. */ 2824 if (gregdata->n_allocated_bpo_gregs != regindex + 1) 2825 { 2826 gregdata->n_allocated_bpo_gregs = regindex + 1; 2827 *again = true; 2828 } 2829 2830 bpo_gregs_section->size = (regindex + 1) * 8; 2831 } 2832 2833 if (isymbuf != NULL && (unsigned char *) isymbuf != symtab_hdr->contents) 2834 { 2835 if (! link_info->keep_memory) 2836 free (isymbuf); 2837 else 2838 { 2839 /* Cache the symbols for elf_link_input_bfd. */ 2840 symtab_hdr->contents = (unsigned char *) isymbuf; 2841 } 2842 } 2843 2844 BFD_ASSERT(pjsno + pjsno_undefs 2845 == mmix_elf_section_data (sec)->pjs.n_pushj_relocs); 2846 2847 if (elf_section_data (sec)->relocs != internal_relocs) 2848 free (internal_relocs); 2849 2850 if (sec->size < size + mmix_elf_section_data (sec)->pjs.stubs_size_sum) 2851 abort (); 2852 2853 if (sec->size > size + mmix_elf_section_data (sec)->pjs.stubs_size_sum) 2854 { 2855 sec->size = size + mmix_elf_section_data (sec)->pjs.stubs_size_sum; 2856 *again = true; 2857 } 2858 2859 return true; 2860 2861 error_return: 2862 if ((unsigned char *) isymbuf != symtab_hdr->contents) 2863 free (isymbuf); 2864 if (elf_section_data (sec)->relocs != internal_relocs) 2865 free (internal_relocs); 2866 return false; 2867 } 2868 2869 #define ELF_ARCH bfd_arch_mmix 2871 #define ELF_MACHINE_CODE EM_MMIX 2872 #define ELF_TARGET_ID MMIX_ELF_DATA 2873 2874 /* According to mmix-doc page 36 (paragraph 45), this should be (1LL << 48LL). 2875 However, that's too much for something somewhere in the linker part of 2876 BFD; perhaps the start-address has to be a non-zero multiple of this 2877 number, or larger than this number. The symptom is that the linker 2878 complains: "warning: allocated section `.text' not in segment". We 2879 settle for 64k; the page-size used in examples is 8k. 2880 #define ELF_MAXPAGESIZE 0x10000 2881 2882 Unfortunately, this causes excessive padding in the supposedly small 2883 for-education programs that are the expected usage (where people would 2884 inspect output). We stick to 256 bytes just to have *some* default 2885 alignment. */ 2886 #define ELF_MAXPAGESIZE 0x100 2887 2888 #define TARGET_BIG_SYM mmix_elf64_vec 2889 #define TARGET_BIG_NAME "elf64-mmix" 2890 2891 #define elf_info_to_howto_rel NULL 2892 #define elf_info_to_howto mmix_info_to_howto_rela 2893 #define elf_backend_relocate_section mmix_elf_relocate_section 2894 #define elf_backend_gc_mark_hook mmix_elf_gc_mark_hook 2895 2896 #define elf_backend_link_output_symbol_hook \ 2897 mmix_elf_link_output_symbol_hook 2898 #define elf_backend_add_symbol_hook mmix_elf_add_symbol_hook 2899 2900 #define elf_backend_check_relocs mmix_elf_check_relocs 2901 #define elf_backend_symbol_processing mmix_elf_symbol_processing 2902 #define elf_backend_omit_section_dynsym _bfd_elf_omit_section_dynsym_all 2903 2904 #define bfd_elf64_bfd_copy_link_hash_symbol_type \ 2905 _bfd_generic_copy_link_hash_symbol_type 2906 2907 #define bfd_elf64_bfd_is_local_label_name \ 2908 mmix_elf_is_local_label_name 2909 2910 #define elf_backend_may_use_rel_p 0 2911 #define elf_backend_may_use_rela_p 1 2912 #define elf_backend_default_use_rela_p 1 2913 2914 #define elf_backend_can_gc_sections 1 2915 #define elf_backend_section_from_bfd_section \ 2916 mmix_elf_section_from_bfd_section 2917 2918 #define bfd_elf64_new_section_hook mmix_elf_new_section_hook 2919 #define bfd_elf64_bfd_final_link mmix_elf_final_link 2920 #define bfd_elf64_bfd_relax_section mmix_elf_relax_section 2921 2922 #include "elf64-target.h" 2923
Indexes created Fri May 01 00:23:41 UTC 2026