1 /* MMIX-specific support for 64-bit ELF. 2 Copyright (C) 2001-2022 Free Software Foundation, Inc. 3 Contributed by Hans-Peter Nilsson <hp@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 if (!sec->used_by_bfd) 832 { 833 struct _mmix_elf_section_data *sdata; 834 size_t amt = sizeof (*sdata); 835 836 sdata = bfd_zalloc (abfd, amt); 837 if (sdata == NULL) 838 return false; 839 sec->used_by_bfd = sdata; 840 } 841 842 return _bfd_elf_new_section_hook (abfd, sec); 843 } 844 845 846 /* This function performs the actual bitfiddling and sanity check for a 847 final relocation. Each relocation gets its *worst*-case expansion 848 in size when it arrives here; any reduction in size should have been 849 caught in linker relaxation earlier. When we get here, the relocation 850 looks like the smallest instruction with SWYM:s (nop:s) appended to the 851 max size. We fill in those nop:s. 852 853 R_MMIX_GETA: (FIXME: Relaxation should break this up in 1, 2, 3 tetra) 854 GETA $N,foo 855 -> 856 SETL $N,foo & 0xffff 857 INCML $N,(foo >> 16) & 0xffff 858 INCMH $N,(foo >> 32) & 0xffff 859 INCH $N,(foo >> 48) & 0xffff 860 861 R_MMIX_CBRANCH: (FIXME: Relaxation should break this up, but 862 condbranches needing relaxation might be rare enough to not be 863 worthwhile.) 864 [P]Bcc $N,foo 865 -> 866 [~P]B~cc $N,.+20 867 SETL $255,foo & ... 868 INCML ... 869 INCMH ... 870 INCH ... 871 GO $255,$255,0 872 873 R_MMIX_PUSHJ: (FIXME: Relaxation...) 874 PUSHJ $N,foo 875 -> 876 SETL $255,foo & ... 877 INCML ... 878 INCMH ... 879 INCH ... 880 PUSHGO $N,$255,0 881 882 R_MMIX_JMP: (FIXME: Relaxation...) 883 JMP foo 884 -> 885 SETL $255,foo & ... 886 INCML ... 887 INCMH ... 888 INCH ... 889 GO $255,$255,0 890 891 R_MMIX_ADDR19 and R_MMIX_ADDR27 are just filled in. */ 892 893 static bfd_reloc_status_type 894 mmix_elf_perform_relocation (asection *isec, reloc_howto_type *howto, 895 void *datap, bfd_vma addr, bfd_vma value, 896 char **error_message) 897 { 898 bfd *abfd = isec->owner; 899 bfd_reloc_status_type flag = bfd_reloc_ok; 900 bfd_reloc_status_type r; 901 int offs = 0; 902 int reg = 255; 903 904 /* The worst case bits are all similar SETL/INCML/INCMH/INCH sequences. 905 We handle the differences here and the common sequence later. */ 906 switch (howto->type) 907 { 908 case R_MMIX_GETA: 909 offs = 0; 910 reg = bfd_get_8 (abfd, (bfd_byte *) datap + 1); 911 912 /* We change to an absolute value. */ 913 value += addr; 914 break; 915 916 case R_MMIX_CBRANCH: 917 { 918 int in1 = bfd_get_16 (abfd, (bfd_byte *) datap) << 16; 919 920 /* Invert the condition and prediction bit, and set the offset 921 to five instructions ahead. 922 923 We *can* do better if we want to. If the branch is found to be 924 within limits, we could leave the branch as is; there'll just 925 be a bunch of NOP:s after it. But we shouldn't see this 926 sequence often enough that it's worth doing it. */ 927 928 bfd_put_32 (abfd, 929 (((in1 ^ ((PRED_INV_BIT | COND_INV_BIT) << 24)) & ~0xffff) 930 | (24/4)), 931 (bfd_byte *) datap); 932 933 /* Put a "GO $255,$255,0" after the common sequence. */ 934 bfd_put_32 (abfd, 935 ((GO_INSN_BYTE | IMM_OFFSET_BIT) << 24) | 0xffff00, 936 (bfd_byte *) datap + 20); 937 938 /* Common sequence starts at offset 4. */ 939 offs = 4; 940 941 /* We change to an absolute value. */ 942 value += addr; 943 } 944 break; 945 946 case R_MMIX_PUSHJ_STUBBABLE: 947 /* If the address fits, we're fine. */ 948 if ((value & 3) == 0 949 /* Note rightshift 0; see R_MMIX_JMP case below. */ 950 && (r = bfd_check_overflow (complain_overflow_signed, 951 howto->bitsize, 952 0, 953 bfd_arch_bits_per_address (abfd), 954 value)) == bfd_reloc_ok) 955 goto pcrel_mmix_reloc_fits; 956 else 957 { 958 bfd_size_type size = isec->rawsize ? isec->rawsize : isec->size; 959 960 /* We have the bytes at the PUSHJ insn and need to get the 961 position for the stub. There's supposed to be room allocated 962 for the stub. */ 963 bfd_byte *stubcontents 964 = ((bfd_byte *) datap 965 - (addr - (isec->output_section->vma + isec->output_offset)) 966 + size 967 + mmix_elf_section_data (isec)->pjs.stub_offset); 968 bfd_vma stubaddr; 969 970 if (mmix_elf_section_data (isec)->pjs.n_pushj_relocs == 0) 971 { 972 /* This shouldn't happen when linking to ELF or mmo, so 973 this is an attempt to link to "binary", right? We 974 can't access the output bfd, so we can't verify that 975 assumption. We only know that the critical 976 mmix_elf_check_common_relocs has not been called, 977 which happens when the output format is different 978 from the input format (and is not mmo). */ 979 if (! mmix_elf_section_data (isec)->has_warned_pushj) 980 { 981 /* For the first such error per input section, produce 982 a verbose message. */ 983 *error_message 984 = _("invalid input relocation when producing" 985 " non-ELF, non-mmo format output;" 986 " please use the objcopy program to convert from" 987 " ELF or mmo," 988 " or assemble using" 989 " \"-no-expand\" (for gcc, \"-Wa,-no-expand\""); 990 mmix_elf_section_data (isec)->has_warned_pushj = true; 991 return bfd_reloc_dangerous; 992 } 993 994 /* For subsequent errors, return this one, which is 995 rate-limited but looks a little bit different, 996 hopefully without affecting user-friendliness. */ 997 return bfd_reloc_overflow; 998 } 999 1000 /* The address doesn't fit, so redirect the PUSHJ to the 1001 location of the stub. */ 1002 r = mmix_elf_perform_relocation (isec, 1003 &elf_mmix_howto_table 1004 [R_MMIX_ADDR19], 1005 datap, 1006 addr, 1007 isec->output_section->vma 1008 + isec->output_offset 1009 + size 1010 + (mmix_elf_section_data (isec) 1011 ->pjs.stub_offset) 1012 - addr, 1013 error_message); 1014 if (r != bfd_reloc_ok) 1015 return r; 1016 1017 stubaddr 1018 = (isec->output_section->vma 1019 + isec->output_offset 1020 + size 1021 + mmix_elf_section_data (isec)->pjs.stub_offset); 1022 1023 /* We generate a simple JMP if that suffices, else the whole 5 1024 insn stub. */ 1025 if (bfd_check_overflow (complain_overflow_signed, 1026 elf_mmix_howto_table[R_MMIX_ADDR27].bitsize, 1027 0, 1028 bfd_arch_bits_per_address (abfd), 1029 addr + value - stubaddr) == bfd_reloc_ok) 1030 { 1031 bfd_put_32 (abfd, JMP_INSN_BYTE << 24, stubcontents); 1032 r = mmix_elf_perform_relocation (isec, 1033 &elf_mmix_howto_table 1034 [R_MMIX_ADDR27], 1035 stubcontents, 1036 stubaddr, 1037 value + addr - stubaddr, 1038 error_message); 1039 mmix_elf_section_data (isec)->pjs.stub_offset += 4; 1040 1041 if (size + mmix_elf_section_data (isec)->pjs.stub_offset 1042 > isec->size) 1043 abort (); 1044 1045 return r; 1046 } 1047 else 1048 { 1049 /* Put a "GO $255,0" after the common sequence. */ 1050 bfd_put_32 (abfd, 1051 ((GO_INSN_BYTE | IMM_OFFSET_BIT) << 24) 1052 | 0xff00, (bfd_byte *) stubcontents + 16); 1053 1054 /* Prepare for the general code to set the first part of the 1055 linker stub, and */ 1056 value += addr; 1057 datap = stubcontents; 1058 mmix_elf_section_data (isec)->pjs.stub_offset 1059 += MAX_PUSHJ_STUB_SIZE; 1060 } 1061 } 1062 break; 1063 1064 case R_MMIX_PUSHJ: 1065 { 1066 int inreg = bfd_get_8 (abfd, (bfd_byte *) datap + 1); 1067 1068 /* Put a "PUSHGO $N,$255,0" after the common sequence. */ 1069 bfd_put_32 (abfd, 1070 ((PUSHGO_INSN_BYTE | IMM_OFFSET_BIT) << 24) 1071 | (inreg << 16) 1072 | 0xff00, 1073 (bfd_byte *) datap + 16); 1074 1075 /* We change to an absolute value. */ 1076 value += addr; 1077 } 1078 break; 1079 1080 case R_MMIX_JMP: 1081 /* This one is a little special. If we get here on a non-relaxing 1082 link, and the destination is actually in range, we don't need to 1083 execute the nops. 1084 If so, we fall through to the bit-fiddling relocs. 1085 1086 FIXME: bfd_check_overflow seems broken; the relocation is 1087 rightshifted before testing, so supply a zero rightshift. */ 1088 1089 if (! ((value & 3) == 0 1090 && (r = bfd_check_overflow (complain_overflow_signed, 1091 howto->bitsize, 1092 0, 1093 bfd_arch_bits_per_address (abfd), 1094 value)) == bfd_reloc_ok)) 1095 { 1096 /* If the relocation doesn't fit in a JMP, we let the NOP:s be 1097 modified below, and put a "GO $255,$255,0" after the 1098 address-loading sequence. */ 1099 bfd_put_32 (abfd, 1100 ((GO_INSN_BYTE | IMM_OFFSET_BIT) << 24) 1101 | 0xffff00, 1102 (bfd_byte *) datap + 16); 1103 1104 /* We change to an absolute value. */ 1105 value += addr; 1106 break; 1107 } 1108 /* FALLTHROUGH. */ 1109 case R_MMIX_ADDR19: 1110 case R_MMIX_ADDR27: 1111 pcrel_mmix_reloc_fits: 1112 /* These must be in range, or else we emit an error. */ 1113 if ((value & 3) == 0 1114 /* Note rightshift 0; see above. */ 1115 && (r = bfd_check_overflow (complain_overflow_signed, 1116 howto->bitsize, 1117 0, 1118 bfd_arch_bits_per_address (abfd), 1119 value)) == bfd_reloc_ok) 1120 { 1121 bfd_vma in1 1122 = bfd_get_32 (abfd, (bfd_byte *) datap); 1123 bfd_vma highbit; 1124 1125 if ((bfd_signed_vma) value < 0) 1126 { 1127 highbit = 1 << 24; 1128 value += (1 << (howto->bitsize - 1)); 1129 } 1130 else 1131 highbit = 0; 1132 1133 value >>= 2; 1134 1135 bfd_put_32 (abfd, 1136 (in1 & howto->src_mask) 1137 | highbit 1138 | (value & howto->dst_mask), 1139 (bfd_byte *) datap); 1140 1141 return bfd_reloc_ok; 1142 } 1143 else 1144 return bfd_reloc_overflow; 1145 1146 case R_MMIX_BASE_PLUS_OFFSET: 1147 { 1148 struct bpo_reloc_section_info *bpodata 1149 = mmix_elf_section_data (isec)->bpo.reloc; 1150 asection *bpo_greg_section; 1151 struct bpo_greg_section_info *gregdata; 1152 size_t bpo_index; 1153 1154 if (bpodata == NULL) 1155 { 1156 /* This shouldn't happen when linking to ELF or mmo, so 1157 this is an attempt to link to "binary", right? We 1158 can't access the output bfd, so we can't verify that 1159 assumption. We only know that the critical 1160 mmix_elf_check_common_relocs has not been called, which 1161 happens when the output format is different from the 1162 input format (and is not mmo). */ 1163 if (! mmix_elf_section_data (isec)->has_warned_bpo) 1164 { 1165 /* For the first such error per input section, produce 1166 a verbose message. */ 1167 *error_message 1168 = _("invalid input relocation when producing" 1169 " non-ELF, non-mmo format output;" 1170 " please use the objcopy program to convert from" 1171 " ELF or mmo," 1172 " or compile using the gcc-option" 1173 " \"-mno-base-addresses\"."); 1174 mmix_elf_section_data (isec)->has_warned_bpo = true; 1175 return bfd_reloc_dangerous; 1176 } 1177 1178 /* For subsequent errors, return this one, which is 1179 rate-limited but looks a little bit different, 1180 hopefully without affecting user-friendliness. */ 1181 return bfd_reloc_overflow; 1182 } 1183 1184 bpo_greg_section = bpodata->bpo_greg_section; 1185 gregdata = mmix_elf_section_data (bpo_greg_section)->bpo.greg; 1186 bpo_index = gregdata->bpo_reloc_indexes[bpodata->bpo_index++]; 1187 1188 /* A consistency check: The value we now have in "relocation" must 1189 be the same as the value we stored for that relocation. It 1190 doesn't cost much, so can be left in at all times. */ 1191 if (value != gregdata->reloc_request[bpo_index].value) 1192 { 1193 _bfd_error_handler 1194 /* xgettext:c-format */ 1195 (_("%pB: Internal inconsistency error for value for\n\ 1196 linker-allocated global register: linked: %#" PRIx64 " != relaxed: %#" PRIx64 ""), 1197 isec->owner, 1198 (uint64_t) value, 1199 (uint64_t) gregdata->reloc_request[bpo_index].value); 1200 bfd_set_error (bfd_error_bad_value); 1201 return bfd_reloc_overflow; 1202 } 1203 1204 /* Then store the register number and offset for that register 1205 into datap and datap + 1 respectively. */ 1206 bfd_put_8 (abfd, 1207 gregdata->reloc_request[bpo_index].regindex 1208 + bpo_greg_section->output_section->vma / 8, 1209 datap); 1210 bfd_put_8 (abfd, 1211 gregdata->reloc_request[bpo_index].offset, 1212 ((unsigned char *) datap) + 1); 1213 return bfd_reloc_ok; 1214 } 1215 1216 case R_MMIX_REG_OR_BYTE: 1217 case R_MMIX_REG: 1218 if (value > 255) 1219 return bfd_reloc_overflow; 1220 bfd_put_8 (abfd, value, datap); 1221 return bfd_reloc_ok; 1222 1223 default: 1224 BAD_CASE (howto->type); 1225 } 1226 1227 /* This code adds the common SETL/INCML/INCMH/INCH worst-case 1228 sequence. */ 1229 1230 /* Lowest two bits must be 0. We return bfd_reloc_overflow for 1231 everything that looks strange. */ 1232 if (value & 3) 1233 flag = bfd_reloc_overflow; 1234 1235 bfd_put_32 (abfd, 1236 (SETL_INSN_BYTE << 24) | (value & 0xffff) | (reg << 16), 1237 (bfd_byte *) datap + offs); 1238 bfd_put_32 (abfd, 1239 (INCML_INSN_BYTE << 24) | ((value >> 16) & 0xffff) | (reg << 16), 1240 (bfd_byte *) datap + offs + 4); 1241 bfd_put_32 (abfd, 1242 (INCMH_INSN_BYTE << 24) | ((value >> 32) & 0xffff) | (reg << 16), 1243 (bfd_byte *) datap + offs + 8); 1244 bfd_put_32 (abfd, 1245 (INCH_INSN_BYTE << 24) | ((value >> 48) & 0xffff) | (reg << 16), 1246 (bfd_byte *) datap + offs + 12); 1247 1248 return flag; 1249 } 1250 1251 /* Set the howto pointer for an MMIX ELF reloc (type RELA). */ 1252 1253 static bool 1254 mmix_info_to_howto_rela (bfd *abfd, 1255 arelent *cache_ptr, 1256 Elf_Internal_Rela *dst) 1257 { 1258 unsigned int r_type; 1259 1260 r_type = ELF64_R_TYPE (dst->r_info); 1261 if (r_type >= (unsigned int) R_MMIX_max) 1262 { 1263 /* xgettext:c-format */ 1264 _bfd_error_handler (_("%pB: unsupported relocation type %#x"), 1265 abfd, r_type); 1266 bfd_set_error (bfd_error_bad_value); 1267 return false; 1268 } 1269 cache_ptr->howto = &elf_mmix_howto_table[r_type]; 1270 return true; 1271 } 1272 1273 /* Any MMIX-specific relocation gets here at assembly time or when linking 1274 to other formats (such as mmo); this is the relocation function from 1275 the reloc_table. We don't get here for final pure ELF linking. */ 1276 1277 static bfd_reloc_status_type 1278 mmix_elf_reloc (bfd *abfd, 1279 arelent *reloc_entry, 1280 asymbol *symbol, 1281 void * data, 1282 asection *input_section, 1283 bfd *output_bfd, 1284 char **error_message) 1285 { 1286 bfd_vma relocation; 1287 bfd_reloc_status_type r; 1288 asection *reloc_target_output_section; 1289 bfd_reloc_status_type flag = bfd_reloc_ok; 1290 bfd_vma output_base = 0; 1291 1292 r = bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data, 1293 input_section, output_bfd, error_message); 1294 1295 /* If that was all that was needed (i.e. this isn't a final link, only 1296 some segment adjustments), we're done. */ 1297 if (r != bfd_reloc_continue) 1298 return r; 1299 1300 if (bfd_is_und_section (symbol->section) 1301 && (symbol->flags & BSF_WEAK) == 0 1302 && output_bfd == (bfd *) NULL) 1303 return bfd_reloc_undefined; 1304 1305 /* Is the address of the relocation really within the section? */ 1306 if (reloc_entry->address > bfd_get_section_limit (abfd, input_section)) 1307 return bfd_reloc_outofrange; 1308 1309 /* Work out which section the relocation is targeted at and the 1310 initial relocation command value. */ 1311 1312 /* Get symbol value. (Common symbols are special.) */ 1313 if (bfd_is_com_section (symbol->section)) 1314 relocation = 0; 1315 else 1316 relocation = symbol->value; 1317 1318 reloc_target_output_section = bfd_asymbol_section (symbol)->output_section; 1319 1320 /* Here the variable relocation holds the final address of the symbol we 1321 are relocating against, plus any addend. */ 1322 if (output_bfd) 1323 output_base = 0; 1324 else 1325 output_base = reloc_target_output_section->vma; 1326 1327 relocation += output_base + symbol->section->output_offset; 1328 1329 if (output_bfd != (bfd *) NULL) 1330 { 1331 /* Add in supplied addend. */ 1332 relocation += reloc_entry->addend; 1333 1334 /* This is a partial relocation, and we want to apply the 1335 relocation to the reloc entry rather than the raw data. 1336 Modify the reloc inplace to reflect what we now know. */ 1337 reloc_entry->addend = relocation; 1338 reloc_entry->address += input_section->output_offset; 1339 return flag; 1340 } 1341 1342 return mmix_final_link_relocate (reloc_entry->howto, input_section, 1343 data, reloc_entry->address, 1344 reloc_entry->addend, relocation, 1345 bfd_asymbol_name (symbol), 1346 reloc_target_output_section, 1347 error_message); 1348 } 1349 1350 /* Relocate an MMIX ELF section. Modified from elf32-fr30.c; look to it 1351 for guidance if you're thinking of copying this. */ 1352 1353 static int 1354 mmix_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED, 1355 struct bfd_link_info *info, 1356 bfd *input_bfd, 1357 asection *input_section, 1358 bfd_byte *contents, 1359 Elf_Internal_Rela *relocs, 1360 Elf_Internal_Sym *local_syms, 1361 asection **local_sections) 1362 { 1363 Elf_Internal_Shdr *symtab_hdr; 1364 struct elf_link_hash_entry **sym_hashes; 1365 Elf_Internal_Rela *rel; 1366 Elf_Internal_Rela *relend; 1367 bfd_size_type size; 1368 size_t pjsno = 0; 1369 1370 size = input_section->rawsize ? input_section->rawsize : input_section->size; 1371 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; 1372 sym_hashes = elf_sym_hashes (input_bfd); 1373 relend = relocs + input_section->reloc_count; 1374 1375 /* Zero the stub area before we start. */ 1376 if (input_section->rawsize != 0 1377 && input_section->size > input_section->rawsize) 1378 memset (contents + input_section->rawsize, 0, 1379 input_section->size - input_section->rawsize); 1380 1381 for (rel = relocs; rel < relend; rel ++) 1382 { 1383 reloc_howto_type *howto; 1384 unsigned long r_symndx; 1385 Elf_Internal_Sym *sym; 1386 asection *sec; 1387 struct elf_link_hash_entry *h; 1388 bfd_vma relocation; 1389 bfd_reloc_status_type r; 1390 const char *name = NULL; 1391 int r_type; 1392 bool undefined_signalled = false; 1393 1394 r_type = ELF64_R_TYPE (rel->r_info); 1395 1396 if (r_type == R_MMIX_GNU_VTINHERIT 1397 || r_type == R_MMIX_GNU_VTENTRY) 1398 continue; 1399 1400 r_symndx = ELF64_R_SYM (rel->r_info); 1401 1402 howto = elf_mmix_howto_table + ELF64_R_TYPE (rel->r_info); 1403 h = NULL; 1404 sym = NULL; 1405 sec = NULL; 1406 1407 if (r_symndx < symtab_hdr->sh_info) 1408 { 1409 sym = local_syms + r_symndx; 1410 sec = local_sections [r_symndx]; 1411 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel); 1412 1413 name = bfd_elf_string_from_elf_section (input_bfd, 1414 symtab_hdr->sh_link, 1415 sym->st_name); 1416 if (name == NULL) 1417 name = bfd_section_name (sec); 1418 } 1419 else 1420 { 1421 bool unresolved_reloc, ignored; 1422 1423 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 1424 r_symndx, symtab_hdr, sym_hashes, 1425 h, sec, relocation, 1426 unresolved_reloc, undefined_signalled, 1427 ignored); 1428 name = h->root.root.string; 1429 } 1430 1431 if (sec != NULL && discarded_section (sec)) 1432 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section, 1433 rel, 1, relend, howto, 0, contents); 1434 1435 if (bfd_link_relocatable (info)) 1436 { 1437 /* This is a relocatable link. For most relocs we don't have to 1438 change anything, unless the reloc is against a section 1439 symbol, in which case we have to adjust according to where 1440 the section symbol winds up in the output section. */ 1441 if (sym != NULL && ELF_ST_TYPE (sym->st_info) == STT_SECTION) 1442 rel->r_addend += sec->output_offset; 1443 1444 /* For PUSHJ stub relocs however, we may need to change the 1445 reloc and the section contents, if the reloc doesn't reach 1446 beyond the end of the output section and previous stubs. 1447 Then we change the section contents to be a PUSHJ to the end 1448 of the input section plus stubs (we can do that without using 1449 a reloc), and then we change the reloc to be a R_MMIX_PUSHJ 1450 at the stub location. */ 1451 if (r_type == R_MMIX_PUSHJ_STUBBABLE) 1452 { 1453 /* We've already checked whether we need a stub; use that 1454 knowledge. */ 1455 if (mmix_elf_section_data (input_section)->pjs.stub_size[pjsno] 1456 != 0) 1457 { 1458 Elf_Internal_Rela relcpy; 1459 1460 if (mmix_elf_section_data (input_section) 1461 ->pjs.stub_size[pjsno] != MAX_PUSHJ_STUB_SIZE) 1462 abort (); 1463 1464 /* There's already a PUSHJ insn there, so just fill in 1465 the offset bits to the stub. */ 1466 if (mmix_final_link_relocate (elf_mmix_howto_table 1467 + R_MMIX_ADDR19, 1468 input_section, 1469 contents, 1470 rel->r_offset, 1471 0, 1472 input_section 1473 ->output_section->vma 1474 + input_section->output_offset 1475 + size 1476 + mmix_elf_section_data (input_section) 1477 ->pjs.stub_offset, 1478 NULL, NULL, NULL) != bfd_reloc_ok) 1479 return false; 1480 1481 /* Put a JMP insn at the stub; it goes with the 1482 R_MMIX_JMP reloc. */ 1483 bfd_put_32 (output_bfd, JMP_INSN_BYTE << 24, 1484 contents 1485 + size 1486 + mmix_elf_section_data (input_section) 1487 ->pjs.stub_offset); 1488 1489 /* Change the reloc to be at the stub, and to a full 1490 R_MMIX_JMP reloc. */ 1491 rel->r_info = ELF64_R_INFO (r_symndx, R_MMIX_JMP); 1492 rel->r_offset 1493 = (size 1494 + mmix_elf_section_data (input_section) 1495 ->pjs.stub_offset); 1496 1497 mmix_elf_section_data (input_section)->pjs.stub_offset 1498 += MAX_PUSHJ_STUB_SIZE; 1499 1500 /* Shift this reloc to the end of the relocs to maintain 1501 the r_offset sorted reloc order. */ 1502 relcpy = *rel; 1503 memmove (rel, rel + 1, (char *) relend - (char *) rel); 1504 relend[-1] = relcpy; 1505 1506 /* Back up one reloc, or else we'd skip the next reloc 1507 in turn. */ 1508 rel--; 1509 } 1510 1511 pjsno++; 1512 } 1513 continue; 1514 } 1515 1516 r = mmix_final_link_relocate (howto, input_section, 1517 contents, rel->r_offset, 1518 rel->r_addend, relocation, name, sec, NULL); 1519 1520 if (r != bfd_reloc_ok) 1521 { 1522 const char * msg = (const char *) NULL; 1523 1524 switch (r) 1525 { 1526 case bfd_reloc_overflow: 1527 info->callbacks->reloc_overflow 1528 (info, (h ? &h->root : NULL), name, howto->name, 1529 (bfd_vma) 0, input_bfd, input_section, rel->r_offset); 1530 break; 1531 1532 case bfd_reloc_undefined: 1533 /* We may have sent this message above. */ 1534 if (! undefined_signalled) 1535 info->callbacks->undefined_symbol 1536 (info, name, input_bfd, input_section, rel->r_offset, true); 1537 undefined_signalled = true; 1538 break; 1539 1540 case bfd_reloc_outofrange: 1541 msg = _("internal error: out of range error"); 1542 break; 1543 1544 case bfd_reloc_notsupported: 1545 msg = _("internal error: unsupported relocation error"); 1546 break; 1547 1548 case bfd_reloc_dangerous: 1549 msg = _("internal error: dangerous relocation"); 1550 break; 1551 1552 default: 1553 msg = _("internal error: unknown error"); 1554 break; 1555 } 1556 1557 if (msg) 1558 (*info->callbacks->warning) (info, msg, name, input_bfd, 1559 input_section, rel->r_offset); 1560 } 1561 } 1562 1563 return true; 1564 } 1565 1566 /* Perform a single relocation. By default we use the standard BFD 1567 routines. A few relocs we have to do ourselves. */ 1568 1569 static bfd_reloc_status_type 1570 mmix_final_link_relocate (reloc_howto_type *howto, asection *input_section, 1571 bfd_byte *contents, bfd_vma r_offset, 1572 bfd_signed_vma r_addend, bfd_vma relocation, 1573 const char *symname, asection *symsec, 1574 char **error_message) 1575 { 1576 bfd_reloc_status_type r = bfd_reloc_ok; 1577 bfd_vma addr 1578 = (input_section->output_section->vma 1579 + input_section->output_offset 1580 + r_offset); 1581 bfd_signed_vma srel 1582 = (bfd_signed_vma) relocation + r_addend; 1583 1584 switch (howto->type) 1585 { 1586 /* All these are PC-relative. */ 1587 case R_MMIX_PUSHJ_STUBBABLE: 1588 case R_MMIX_PUSHJ: 1589 case R_MMIX_CBRANCH: 1590 case R_MMIX_ADDR19: 1591 case R_MMIX_GETA: 1592 case R_MMIX_ADDR27: 1593 case R_MMIX_JMP: 1594 contents += r_offset; 1595 1596 srel -= (input_section->output_section->vma 1597 + input_section->output_offset 1598 + r_offset); 1599 1600 r = mmix_elf_perform_relocation (input_section, howto, contents, 1601 addr, srel, error_message); 1602 break; 1603 1604 case R_MMIX_BASE_PLUS_OFFSET: 1605 if (symsec == NULL) 1606 return bfd_reloc_undefined; 1607 1608 /* Check that we're not relocating against a register symbol. */ 1609 if (strcmp (bfd_section_name (symsec), 1610 MMIX_REG_CONTENTS_SECTION_NAME) == 0 1611 || strcmp (bfd_section_name (symsec), 1612 MMIX_REG_SECTION_NAME) == 0) 1613 { 1614 /* Note: This is separated out into two messages in order 1615 to ease the translation into other languages. */ 1616 if (symname == NULL || *symname == 0) 1617 _bfd_error_handler 1618 /* xgettext:c-format */ 1619 (_("%pB: base-plus-offset relocation against register symbol:" 1620 " (unknown) in %pA"), 1621 input_section->owner, symsec); 1622 else 1623 _bfd_error_handler 1624 /* xgettext:c-format */ 1625 (_("%pB: base-plus-offset relocation against register symbol:" 1626 " %s in %pA"), 1627 input_section->owner, symname, symsec); 1628 return bfd_reloc_overflow; 1629 } 1630 goto do_mmix_reloc; 1631 1632 case R_MMIX_REG_OR_BYTE: 1633 case R_MMIX_REG: 1634 /* For now, we handle these alike. They must refer to an register 1635 symbol, which is either relative to the register section and in 1636 the range 0..255, or is in the register contents section with vma 1637 regno * 8. */ 1638 1639 /* FIXME: A better way to check for reg contents section? 1640 FIXME: Postpone section->scaling to mmix_elf_perform_relocation? */ 1641 if (symsec == NULL) 1642 return bfd_reloc_undefined; 1643 1644 if (strcmp (bfd_section_name (symsec), 1645 MMIX_REG_CONTENTS_SECTION_NAME) == 0) 1646 { 1647 if ((srel & 7) != 0 || srel < 32*8 || srel > 255*8) 1648 { 1649 /* The bfd_reloc_outofrange return value, though intuitively 1650 a better value, will not get us an error. */ 1651 return bfd_reloc_overflow; 1652 } 1653 srel /= 8; 1654 } 1655 else if (strcmp (bfd_section_name (symsec), 1656 MMIX_REG_SECTION_NAME) == 0) 1657 { 1658 if (srel < 0 || srel > 255) 1659 /* The bfd_reloc_outofrange return value, though intuitively a 1660 better value, will not get us an error. */ 1661 return bfd_reloc_overflow; 1662 } 1663 else 1664 { 1665 /* Note: This is separated out into two messages in order 1666 to ease the translation into other languages. */ 1667 if (symname == NULL || *symname == 0) 1668 _bfd_error_handler 1669 /* xgettext:c-format */ 1670 (_("%pB: register relocation against non-register symbol:" 1671 " (unknown) in %pA"), 1672 input_section->owner, symsec); 1673 else 1674 _bfd_error_handler 1675 /* xgettext:c-format */ 1676 (_("%pB: register relocation against non-register symbol:" 1677 " %s in %pA"), 1678 input_section->owner, symname, symsec); 1679 1680 /* The bfd_reloc_outofrange return value, though intuitively a 1681 better value, will not get us an error. */ 1682 return bfd_reloc_overflow; 1683 } 1684 do_mmix_reloc: 1685 contents += r_offset; 1686 r = mmix_elf_perform_relocation (input_section, howto, contents, 1687 addr, srel, error_message); 1688 break; 1689 1690 case R_MMIX_LOCAL: 1691 /* This isn't a real relocation, it's just an assertion that the 1692 final relocation value corresponds to a local register. We 1693 ignore the actual relocation; nothing is changed. */ 1694 { 1695 asection *regsec 1696 = bfd_get_section_by_name (input_section->output_section->owner, 1697 MMIX_REG_CONTENTS_SECTION_NAME); 1698 bfd_vma first_global; 1699 1700 /* Check that this is an absolute value, or a reference to the 1701 register contents section or the register (symbol) section. 1702 Absolute numbers can get here as undefined section. Undefined 1703 symbols are signalled elsewhere, so there's no conflict in us 1704 accidentally handling it. */ 1705 if (!bfd_is_abs_section (symsec) 1706 && !bfd_is_und_section (symsec) 1707 && strcmp (bfd_section_name (symsec), 1708 MMIX_REG_CONTENTS_SECTION_NAME) != 0 1709 && strcmp (bfd_section_name (symsec), 1710 MMIX_REG_SECTION_NAME) != 0) 1711 { 1712 _bfd_error_handler 1713 (_("%pB: directive LOCAL valid only with a register or absolute value"), 1714 input_section->owner); 1715 1716 return bfd_reloc_overflow; 1717 } 1718 1719 /* If we don't have a register contents section, then $255 is the 1720 first global register. */ 1721 if (regsec == NULL) 1722 first_global = 255; 1723 else 1724 { 1725 first_global = bfd_section_vma (regsec) / 8; 1726 if (strcmp (bfd_section_name (symsec), 1727 MMIX_REG_CONTENTS_SECTION_NAME) == 0) 1728 { 1729 if ((srel & 7) != 0 || srel < 32*8 || srel > 255*8) 1730 /* The bfd_reloc_outofrange return value, though 1731 intuitively a better value, will not get us an error. */ 1732 return bfd_reloc_overflow; 1733 srel /= 8; 1734 } 1735 } 1736 1737 if ((bfd_vma) srel >= first_global) 1738 { 1739 /* FIXME: Better error message. */ 1740 _bfd_error_handler 1741 /* xgettext:c-format */ 1742 (_("%pB: LOCAL directive: " 1743 "register $%" PRId64 " is not a local register;" 1744 " first global register is $%" PRId64), 1745 input_section->owner, (int64_t) srel, (int64_t) first_global); 1746 1747 return bfd_reloc_overflow; 1748 } 1749 } 1750 r = bfd_reloc_ok; 1751 break; 1752 1753 default: 1754 r = _bfd_final_link_relocate (howto, input_section->owner, input_section, 1755 contents, r_offset, 1756 relocation, r_addend); 1757 } 1758 1759 return r; 1760 } 1761 1762 /* Return the section that should be marked against GC for a given 1763 relocation. */ 1764 1765 static asection * 1766 mmix_elf_gc_mark_hook (asection *sec, 1767 struct bfd_link_info *info, 1768 Elf_Internal_Rela *rel, 1769 struct elf_link_hash_entry *h, 1770 Elf_Internal_Sym *sym) 1771 { 1772 if (h != NULL) 1773 switch (ELF64_R_TYPE (rel->r_info)) 1774 { 1775 case R_MMIX_GNU_VTINHERIT: 1776 case R_MMIX_GNU_VTENTRY: 1777 return NULL; 1778 } 1779 1780 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 1781 } 1782 1783 /* 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 2052 the register section, and scale them down to correspond to the register 2053 number. */ 2054 2055 static int 2056 mmix_elf_link_output_symbol_hook (struct bfd_link_info *info ATTRIBUTE_UNUSED, 2057 const char *name ATTRIBUTE_UNUSED, 2058 Elf_Internal_Sym *sym, 2059 asection *input_sec, 2060 struct elf_link_hash_entry *h ATTRIBUTE_UNUSED) 2061 { 2062 if (input_sec != NULL 2063 && input_sec->name != NULL 2064 && ELF_ST_TYPE (sym->st_info) != STT_SECTION 2065 && strcmp (input_sec->name, MMIX_REG_CONTENTS_SECTION_NAME) == 0) 2066 { 2067 sym->st_value /= 8; 2068 sym->st_shndx = SHN_REGISTER; 2069 } 2070 2071 return 1; 2072 } 2073 2074 /* We fake a register section that holds values that are register numbers. 2075 Having a SHN_REGISTER and register section translates better to other 2076 formats (e.g. mmo) than for example a STT_REGISTER attribute. 2077 This section faking is based on a construct in elf32-mips.c. */ 2078 static asection mmix_elf_reg_section; 2079 static const asymbol mmix_elf_reg_section_symbol = 2080 GLOBAL_SYM_INIT (MMIX_REG_SECTION_NAME, &mmix_elf_reg_section); 2081 static asection mmix_elf_reg_section = 2082 BFD_FAKE_SECTION (mmix_elf_reg_section, &mmix_elf_reg_section_symbol, 2083 MMIX_REG_SECTION_NAME, 0, SEC_NO_FLAGS); 2084 2085 /* Handle the special section numbers that a symbol may use. */ 2086 2087 void 2088 mmix_elf_symbol_processing (bfd *abfd ATTRIBUTE_UNUSED, asymbol *asym) 2089 { 2090 elf_symbol_type *elfsym; 2091 2092 elfsym = (elf_symbol_type *) asym; 2093 switch (elfsym->internal_elf_sym.st_shndx) 2094 { 2095 case SHN_REGISTER: 2096 asym->section = &mmix_elf_reg_section; 2097 break; 2098 2099 default: 2100 break; 2101 } 2102 } 2103 2104 /* Given a BFD section, try to locate the corresponding ELF section 2105 index. */ 2106 2107 static bool 2108 mmix_elf_section_from_bfd_section (bfd * abfd ATTRIBUTE_UNUSED, 2109 asection * sec, 2110 int * retval) 2111 { 2112 if (strcmp (bfd_section_name (sec), MMIX_REG_SECTION_NAME) == 0) 2113 *retval = SHN_REGISTER; 2114 else 2115 return false; 2116 2117 return true; 2118 } 2119 2120 /* Hook called by the linker routine which adds symbols from an object 2121 file. We must handle the special SHN_REGISTER section number here. 2122 2123 We also check that we only have *one* each of the section-start 2124 symbols, since otherwise having two with the same value would cause 2125 them to be "merged", but with the contents serialized. */ 2126 2127 static bool 2128 mmix_elf_add_symbol_hook (bfd *abfd, 2129 struct bfd_link_info *info ATTRIBUTE_UNUSED, 2130 Elf_Internal_Sym *sym, 2131 const char **namep ATTRIBUTE_UNUSED, 2132 flagword *flagsp ATTRIBUTE_UNUSED, 2133 asection **secp, 2134 bfd_vma *valp ATTRIBUTE_UNUSED) 2135 { 2136 if (sym->st_shndx == SHN_REGISTER) 2137 { 2138 *secp = bfd_make_section_old_way (abfd, MMIX_REG_SECTION_NAME); 2139 (*secp)->flags |= SEC_LINKER_CREATED; 2140 } 2141 else if ((*namep)[0] == '_' && (*namep)[1] == '_' && (*namep)[2] == '.' 2142 && startswith (*namep, MMIX_LOC_SECTION_START_SYMBOL_PREFIX)) 2143 { 2144 /* See if we have another one. */ 2145 struct bfd_link_hash_entry *h = bfd_link_hash_lookup (info->hash, 2146 *namep, 2147 false, 2148 false, 2149 false); 2150 2151 if (h != NULL && h->type != bfd_link_hash_undefined) 2152 { 2153 /* How do we get the asymbol (or really: the filename) from h? 2154 h->u.def.section->owner is NULL. */ 2155 _bfd_error_handler 2156 /* xgettext:c-format */ 2157 (_("%pB: error: multiple definition of `%s'; start of %s " 2158 "is set in a earlier linked file"), 2159 abfd, *namep, 2160 *namep + strlen (MMIX_LOC_SECTION_START_SYMBOL_PREFIX)); 2161 bfd_set_error (bfd_error_bad_value); 2162 return false; 2163 } 2164 } 2165 2166 return true; 2167 } 2168 2169 /* We consider symbols matching "L.*:[0-9]+" to be local symbols. */ 2170 2171 static bool 2172 mmix_elf_is_local_label_name (bfd *abfd, const char *name) 2173 { 2174 const char *colpos; 2175 int digits; 2176 2177 /* Also include the default local-label definition. */ 2178 if (_bfd_elf_is_local_label_name (abfd, name)) 2179 return true; 2180 2181 if (*name != 'L') 2182 return false; 2183 2184 /* If there's no ":", or more than one, it's not a local symbol. */ 2185 colpos = strchr (name, ':'); 2186 if (colpos == NULL || strchr (colpos + 1, ':') != NULL) 2187 return false; 2188 2189 /* Check that there are remaining characters and that they are digits. */ 2190 if (colpos[1] == 0) 2191 return false; 2192 2193 digits = strspn (colpos + 1, "0123456789"); 2194 return digits != 0 && colpos[1 + digits] == 0; 2195 } 2196 2197 /* We get rid of the register section here. */ 2198 2199 bool 2200 mmix_elf_final_link (bfd *abfd, struct bfd_link_info *info) 2201 { 2202 /* We never output a register section, though we create one for 2203 temporary measures. Check that nobody entered contents into it. */ 2204 asection *reg_section; 2205 2206 reg_section = bfd_get_section_by_name (abfd, MMIX_REG_SECTION_NAME); 2207 2208 if (reg_section != NULL) 2209 { 2210 /* FIXME: Pass error state gracefully. */ 2211 if (bfd_section_flags (reg_section) & SEC_HAS_CONTENTS) 2212 _bfd_abort (__FILE__, __LINE__, _("register section has contents\n")); 2213 2214 /* Really remove the section, if it hasn't already been done. */ 2215 if (!bfd_section_removed_from_list (abfd, reg_section)) 2216 { 2217 bfd_section_list_remove (abfd, reg_section); 2218 --abfd->section_count; 2219 } 2220 } 2221 2222 if (! bfd_elf_final_link (abfd, info)) 2223 return false; 2224 2225 /* Since this section is marked SEC_LINKER_CREATED, it isn't output by 2226 the regular linker machinery. We do it here, like other targets with 2227 special sections. */ 2228 if (info->base_file != NULL) 2229 { 2230 asection *greg_section 2231 = bfd_get_section_by_name ((bfd *) info->base_file, 2232 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2233 if (!bfd_set_section_contents (abfd, 2234 greg_section->output_section, 2235 greg_section->contents, 2236 (file_ptr) greg_section->output_offset, 2237 greg_section->size)) 2238 return false; 2239 } 2240 return true; 2241 } 2242 2243 /* We need to include the maximum size of PUSHJ-stubs in the initial 2244 section size. This is expected to shrink during linker relaxation. */ 2245 2246 static void 2247 mmix_set_relaxable_size (bfd *abfd ATTRIBUTE_UNUSED, 2248 asection *sec, 2249 void *ptr) 2250 { 2251 struct bfd_link_info *info = ptr; 2252 2253 /* Make sure we only do this for section where we know we want this, 2254 otherwise we might end up resetting the size of COMMONs. */ 2255 if (mmix_elf_section_data (sec)->pjs.n_pushj_relocs == 0) 2256 return; 2257 2258 sec->rawsize = sec->size; 2259 sec->size += (mmix_elf_section_data (sec)->pjs.n_pushj_relocs 2260 * MAX_PUSHJ_STUB_SIZE); 2261 2262 /* For use in relocatable link, we start with a max stubs size. See 2263 mmix_elf_relax_section. */ 2264 if (bfd_link_relocatable (info) && sec->output_section) 2265 mmix_elf_section_data (sec->output_section)->pjs.stubs_size_sum 2266 += (mmix_elf_section_data (sec)->pjs.n_pushj_relocs 2267 * MAX_PUSHJ_STUB_SIZE); 2268 } 2269 2270 /* Initialize stuff for the linker-generated GREGs to match 2271 R_MMIX_BASE_PLUS_OFFSET relocs seen by the linker. */ 2272 2273 bool 2274 _bfd_mmix_before_linker_allocation (bfd *abfd ATTRIBUTE_UNUSED, 2275 struct bfd_link_info *info) 2276 { 2277 asection *bpo_gregs_section; 2278 bfd *bpo_greg_owner; 2279 struct bpo_greg_section_info *gregdata; 2280 size_t n_gregs; 2281 bfd_vma gregs_size; 2282 size_t i; 2283 size_t *bpo_reloc_indexes; 2284 bfd *ibfd; 2285 2286 /* Set the initial size of sections. */ 2287 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next) 2288 bfd_map_over_sections (ibfd, mmix_set_relaxable_size, info); 2289 2290 /* The bpo_greg_owner bfd is supposed to have been set by 2291 mmix_elf_check_relocs when the first R_MMIX_BASE_PLUS_OFFSET is seen. 2292 If there is no such object, there was no R_MMIX_BASE_PLUS_OFFSET. */ 2293 bpo_greg_owner = (bfd *) info->base_file; 2294 if (bpo_greg_owner == NULL) 2295 return true; 2296 2297 bpo_gregs_section 2298 = bfd_get_section_by_name (bpo_greg_owner, 2299 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2300 2301 if (bpo_gregs_section == NULL) 2302 return true; 2303 2304 /* We use the target-data handle in the ELF section data. */ 2305 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2306 if (gregdata == NULL) 2307 return false; 2308 2309 n_gregs = gregdata->n_bpo_relocs; 2310 gregdata->n_allocated_bpo_gregs = n_gregs; 2311 2312 /* When this reaches zero during relaxation, all entries have been 2313 filled in and the size of the linker gregs can be calculated. */ 2314 gregdata->n_remaining_bpo_relocs_this_relaxation_round = n_gregs; 2315 2316 /* Set the zeroth-order estimate for the GREGs size. */ 2317 gregs_size = n_gregs * 8; 2318 2319 if (!bfd_set_section_size (bpo_gregs_section, gregs_size)) 2320 return false; 2321 2322 /* Allocate and set up the GREG arrays. They're filled in at relaxation 2323 time. Note that we must use the max number ever noted for the array, 2324 since the index numbers were created before GC. */ 2325 gregdata->reloc_request 2326 = bfd_zalloc (bpo_greg_owner, 2327 sizeof (struct bpo_reloc_request) 2328 * gregdata->n_max_bpo_relocs); 2329 2330 gregdata->bpo_reloc_indexes 2331 = bpo_reloc_indexes 2332 = bfd_alloc (bpo_greg_owner, 2333 gregdata->n_max_bpo_relocs 2334 * sizeof (size_t)); 2335 if (bpo_reloc_indexes == NULL) 2336 return false; 2337 2338 /* The default order is an identity mapping. */ 2339 for (i = 0; i < gregdata->n_max_bpo_relocs; i++) 2340 { 2341 bpo_reloc_indexes[i] = i; 2342 gregdata->reloc_request[i].bpo_reloc_no = i; 2343 } 2344 2345 return true; 2346 } 2347 2348 /* Fill in contents in the linker allocated gregs. Everything is 2349 calculated at this point; we just move the contents into place here. */ 2350 2351 bool 2352 _bfd_mmix_after_linker_allocation (bfd *abfd ATTRIBUTE_UNUSED, 2353 struct bfd_link_info *link_info) 2354 { 2355 asection *bpo_gregs_section; 2356 bfd *bpo_greg_owner; 2357 struct bpo_greg_section_info *gregdata; 2358 size_t n_gregs; 2359 size_t i, j; 2360 size_t lastreg; 2361 bfd_byte *contents; 2362 2363 /* The bpo_greg_owner bfd is supposed to have been set by mmix_elf_check_relocs 2364 when the first R_MMIX_BASE_PLUS_OFFSET is seen. If there is no such 2365 object, there was no R_MMIX_BASE_PLUS_OFFSET. */ 2366 bpo_greg_owner = (bfd *) link_info->base_file; 2367 if (bpo_greg_owner == NULL) 2368 return true; 2369 2370 bpo_gregs_section 2371 = bfd_get_section_by_name (bpo_greg_owner, 2372 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2373 2374 /* This can't happen without DSO handling. When DSOs are handled 2375 without any R_MMIX_BASE_PLUS_OFFSET seen, there will be no such 2376 section. */ 2377 if (bpo_gregs_section == NULL) 2378 return true; 2379 2380 /* We use the target-data handle in the ELF section data. */ 2381 2382 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2383 if (gregdata == NULL) 2384 return false; 2385 2386 n_gregs = gregdata->n_allocated_bpo_gregs; 2387 2388 bpo_gregs_section->contents 2389 = contents = bfd_alloc (bpo_greg_owner, bpo_gregs_section->size); 2390 if (contents == NULL) 2391 return false; 2392 2393 /* Sanity check: If these numbers mismatch, some relocation has not been 2394 accounted for and the rest of gregdata is probably inconsistent. 2395 It's a bug, but it's more helpful to identify it than segfaulting 2396 below. */ 2397 if (gregdata->n_remaining_bpo_relocs_this_relaxation_round 2398 != gregdata->n_bpo_relocs) 2399 { 2400 _bfd_error_handler 2401 /* xgettext:c-format */ 2402 (_("internal inconsistency: remaining %lu != max %lu;" 2403 " please report this bug"), 2404 (unsigned long) gregdata->n_remaining_bpo_relocs_this_relaxation_round, 2405 (unsigned long) gregdata->n_bpo_relocs); 2406 return false; 2407 } 2408 2409 for (lastreg = 255, i = 0, j = 0; j < n_gregs; i++) 2410 if (gregdata->reloc_request[i].regindex != lastreg) 2411 { 2412 bfd_put_64 (bpo_greg_owner, gregdata->reloc_request[i].value, 2413 contents + j * 8); 2414 lastreg = gregdata->reloc_request[i].regindex; 2415 j++; 2416 } 2417 2418 return true; 2419 } 2420 2421 /* Sort valid relocs to come before non-valid relocs, then on increasing 2422 value. */ 2423 2424 static int 2425 bpo_reloc_request_sort_fn (const void * p1, const void * p2) 2426 { 2427 const struct bpo_reloc_request *r1 = (const struct bpo_reloc_request *) p1; 2428 const struct bpo_reloc_request *r2 = (const struct bpo_reloc_request *) p2; 2429 2430 /* Primary function is validity; non-valid relocs sorted after valid 2431 ones. */ 2432 if (r1->valid != r2->valid) 2433 return r2->valid - r1->valid; 2434 2435 /* Then sort on value. Don't simplify and return just the difference of 2436 the values: the upper bits of the 64-bit value would be truncated on 2437 a host with 32-bit ints. */ 2438 if (r1->value != r2->value) 2439 return r1->value > r2->value ? 1 : -1; 2440 2441 /* As a last re-sort, use the relocation number, so we get a stable 2442 sort. The *addresses* aren't stable since items are swapped during 2443 sorting. It depends on the qsort implementation if this actually 2444 happens. */ 2445 return r1->bpo_reloc_no > r2->bpo_reloc_no 2446 ? 1 : (r1->bpo_reloc_no < r2->bpo_reloc_no ? -1 : 0); 2447 } 2448 2449 /* For debug use only. Dumps the global register allocations resulting 2450 from base-plus-offset relocs. */ 2451 2452 void 2453 mmix_dump_bpo_gregs (struct bfd_link_info *link_info, 2454 void (*pf) (const char *fmt, ...)) 2455 { 2456 bfd *bpo_greg_owner; 2457 asection *bpo_gregs_section; 2458 struct bpo_greg_section_info *gregdata; 2459 unsigned int i; 2460 2461 if (link_info == NULL || link_info->base_file == NULL) 2462 return; 2463 2464 bpo_greg_owner = (bfd *) link_info->base_file; 2465 2466 bpo_gregs_section 2467 = bfd_get_section_by_name (bpo_greg_owner, 2468 MMIX_LD_ALLOCATED_REG_CONTENTS_SECTION_NAME); 2469 2470 if (bpo_gregs_section == NULL) 2471 return; 2472 2473 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2474 if (gregdata == NULL) 2475 return; 2476 2477 if (pf == NULL) 2478 pf = _bfd_error_handler; 2479 2480 /* These format strings are not translated. They are for debug purposes 2481 only and never displayed to an end user. Should they escape, we 2482 surely want them in original. */ 2483 (*pf) (" n_bpo_relocs: %u\n n_max_bpo_relocs: %u\n n_remain...round: %u\n\ 2484 n_allocated_bpo_gregs: %u\n", gregdata->n_bpo_relocs, 2485 gregdata->n_max_bpo_relocs, 2486 gregdata->n_remaining_bpo_relocs_this_relaxation_round, 2487 gregdata->n_allocated_bpo_gregs); 2488 2489 if (gregdata->reloc_request) 2490 for (i = 0; i < gregdata->n_max_bpo_relocs; i++) 2491 (*pf) ("%4u (%4u)/%4u#%u: 0x%08lx%08lx r: %3u o: %3u\n", 2492 i, 2493 (gregdata->bpo_reloc_indexes != NULL 2494 ? gregdata->bpo_reloc_indexes[i] : (size_t) -1), 2495 gregdata->reloc_request[i].bpo_reloc_no, 2496 gregdata->reloc_request[i].valid, 2497 2498 (unsigned long) (gregdata->reloc_request[i].value >> 32), 2499 (unsigned long) gregdata->reloc_request[i].value, 2500 gregdata->reloc_request[i].regindex, 2501 gregdata->reloc_request[i].offset); 2502 } 2503 2504 /* This links all R_MMIX_BASE_PLUS_OFFSET relocs into a special array, and 2505 when the last such reloc is done, an index-array is sorted according to 2506 the values and iterated over to produce register numbers (indexed by 0 2507 from the first allocated register number) and offsets for use in real 2508 relocation. (N.B.: Relocatable runs are handled, not just punted.) 2509 2510 PUSHJ stub accounting is also done here. 2511 2512 Symbol- and reloc-reading infrastructure copied from elf-m10200.c. */ 2513 2514 static bool 2515 mmix_elf_relax_section (bfd *abfd, 2516 asection *sec, 2517 struct bfd_link_info *link_info, 2518 bool *again) 2519 { 2520 Elf_Internal_Shdr *symtab_hdr; 2521 Elf_Internal_Rela *internal_relocs; 2522 Elf_Internal_Rela *irel, *irelend; 2523 asection *bpo_gregs_section = NULL; 2524 struct bpo_greg_section_info *gregdata; 2525 struct bpo_reloc_section_info *bpodata 2526 = mmix_elf_section_data (sec)->bpo.reloc; 2527 /* The initialization is to quiet compiler warnings. The value is to 2528 spot a missing actual initialization. */ 2529 size_t bpono = (size_t) -1; 2530 size_t pjsno = 0; 2531 size_t pjsno_undefs = 0; 2532 Elf_Internal_Sym *isymbuf = NULL; 2533 bfd_size_type size = sec->rawsize ? sec->rawsize : sec->size; 2534 2535 mmix_elf_section_data (sec)->pjs.stubs_size_sum = 0; 2536 2537 /* Assume nothing changes. */ 2538 *again = false; 2539 2540 /* We don't have to do anything if this section does not have relocs, or 2541 if this is not a code section. */ 2542 if ((sec->flags & SEC_RELOC) == 0 2543 || sec->reloc_count == 0 2544 || (sec->flags & SEC_CODE) == 0 2545 || (sec->flags & SEC_LINKER_CREATED) != 0 2546 /* If no R_MMIX_BASE_PLUS_OFFSET relocs and no PUSHJ-stub relocs, 2547 then nothing to do. */ 2548 || (bpodata == NULL 2549 && mmix_elf_section_data (sec)->pjs.n_pushj_relocs == 0)) 2550 return true; 2551 2552 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 2553 2554 if (bpodata != NULL) 2555 { 2556 bpo_gregs_section = bpodata->bpo_greg_section; 2557 gregdata = mmix_elf_section_data (bpo_gregs_section)->bpo.greg; 2558 bpono = bpodata->first_base_plus_offset_reloc; 2559 } 2560 else 2561 gregdata = NULL; 2562 2563 /* Get a copy of the native relocations. */ 2564 internal_relocs 2565 = _bfd_elf_link_read_relocs (abfd, sec, NULL, 2566 (Elf_Internal_Rela *) NULL, 2567 link_info->keep_memory); 2568 if (internal_relocs == NULL) 2569 goto error_return; 2570 2571 /* Walk through them looking for relaxing opportunities. */ 2572 irelend = internal_relocs + sec->reloc_count; 2573 for (irel = internal_relocs; irel < irelend; irel++) 2574 { 2575 bfd_vma symval; 2576 struct elf_link_hash_entry *h = NULL; 2577 2578 /* We only process two relocs. */ 2579 if (ELF64_R_TYPE (irel->r_info) != (int) R_MMIX_BASE_PLUS_OFFSET 2580 && ELF64_R_TYPE (irel->r_info) != (int) R_MMIX_PUSHJ_STUBBABLE) 2581 continue; 2582 2583 /* We process relocs in a distinctly different way when this is a 2584 relocatable link (for one, we don't look at symbols), so we avoid 2585 mixing its code with that for the "normal" relaxation. */ 2586 if (bfd_link_relocatable (link_info)) 2587 { 2588 /* The only transformation in a relocatable link is to generate 2589 a full stub at the location of the stub calculated for the 2590 input section, if the relocated stub location, the end of the 2591 output section plus earlier stubs, cannot be reached. Thus 2592 relocatable linking can only lead to worse code, but it still 2593 works. */ 2594 if (ELF64_R_TYPE (irel->r_info) == R_MMIX_PUSHJ_STUBBABLE) 2595 { 2596 /* If we can reach the end of the output-section and beyond 2597 any current stubs, then we don't need a stub for this 2598 reloc. The relaxed order of output stub allocation may 2599 not exactly match the straightforward order, so we always 2600 assume presence of output stubs, which will allow 2601 relaxation only on relocations indifferent to the 2602 presence of output stub allocations for other relocations 2603 and thus the order of output stub allocation. */ 2604 if (bfd_check_overflow (complain_overflow_signed, 2605 19, 2606 0, 2607 bfd_arch_bits_per_address (abfd), 2608 /* Output-stub location. */ 2609 sec->output_section->rawsize 2610 + (mmix_elf_section_data (sec 2611 ->output_section) 2612 ->pjs.stubs_size_sum) 2613 /* Location of this PUSHJ reloc. */ 2614 - (sec->output_offset + irel->r_offset) 2615 /* Don't count *this* stub twice. */ 2616 - (mmix_elf_section_data (sec) 2617 ->pjs.stub_size[pjsno] 2618 + MAX_PUSHJ_STUB_SIZE)) 2619 == bfd_reloc_ok) 2620 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] = 0; 2621 2622 mmix_elf_section_data (sec)->pjs.stubs_size_sum 2623 += mmix_elf_section_data (sec)->pjs.stub_size[pjsno]; 2624 2625 pjsno++; 2626 } 2627 2628 continue; 2629 } 2630 2631 /* Get the value of the symbol referred to by the reloc. */ 2632 if (ELF64_R_SYM (irel->r_info) < symtab_hdr->sh_info) 2633 { 2634 /* A local symbol. */ 2635 Elf_Internal_Sym *isym; 2636 asection *sym_sec; 2637 2638 /* Read this BFD's local symbols if we haven't already. */ 2639 if (isymbuf == NULL) 2640 { 2641 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents; 2642 if (isymbuf == NULL) 2643 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr, 2644 symtab_hdr->sh_info, 0, 2645 NULL, NULL, NULL); 2646 if (isymbuf == 0) 2647 goto error_return; 2648 } 2649 2650 isym = isymbuf + ELF64_R_SYM (irel->r_info); 2651 if (isym->st_shndx == SHN_UNDEF) 2652 sym_sec = bfd_und_section_ptr; 2653 else if (isym->st_shndx == SHN_ABS) 2654 sym_sec = bfd_abs_section_ptr; 2655 else if (isym->st_shndx == SHN_COMMON) 2656 sym_sec = bfd_com_section_ptr; 2657 else 2658 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx); 2659 symval = (isym->st_value 2660 + sym_sec->output_section->vma 2661 + sym_sec->output_offset); 2662 } 2663 else 2664 { 2665 unsigned long indx; 2666 2667 /* An external symbol. */ 2668 indx = ELF64_R_SYM (irel->r_info) - symtab_hdr->sh_info; 2669 h = elf_sym_hashes (abfd)[indx]; 2670 BFD_ASSERT (h != NULL); 2671 if (h->root.type == bfd_link_hash_undefweak) 2672 /* FIXME: for R_MMIX_PUSHJ_STUBBABLE, there are alternatives to 2673 the canonical value 0 for an unresolved weak symbol to 2674 consider: as the debug-friendly approach, resolve to "abort" 2675 (or a port-specific function), or as the space-friendly 2676 approach resolve to the next instruction (like some other 2677 ports, notably ARM and AArch64). These alternatives require 2678 matching code in mmix_elf_perform_relocation or its caller. */ 2679 symval = 0; 2680 else if (h->root.type == bfd_link_hash_defined 2681 || h->root.type == bfd_link_hash_defweak) 2682 symval = (h->root.u.def.value 2683 + h->root.u.def.section->output_section->vma 2684 + h->root.u.def.section->output_offset); 2685 else 2686 { 2687 /* This appears to be a reference to an undefined symbol. Just 2688 ignore it--it will be caught by the regular reloc processing. 2689 We need to keep BPO reloc accounting consistent, though 2690 else we'll abort instead of emitting an error message. */ 2691 if (ELF64_R_TYPE (irel->r_info) == R_MMIX_BASE_PLUS_OFFSET 2692 && gregdata != NULL) 2693 { 2694 gregdata->n_remaining_bpo_relocs_this_relaxation_round--; 2695 bpono++; 2696 } 2697 2698 /* Similarly, keep accounting consistent for PUSHJ 2699 referring to an undefined symbol. */ 2700 if (ELF64_R_TYPE (irel->r_info) == R_MMIX_PUSHJ_STUBBABLE) 2701 pjsno_undefs++; 2702 continue; 2703 } 2704 } 2705 2706 if (ELF64_R_TYPE (irel->r_info) == (int) R_MMIX_PUSHJ_STUBBABLE) 2707 { 2708 bfd_vma value = symval + irel->r_addend; 2709 bfd_vma dot 2710 = (sec->output_section->vma 2711 + sec->output_offset 2712 + irel->r_offset); 2713 bfd_vma stubaddr 2714 = (sec->output_section->vma 2715 + sec->output_offset 2716 + size 2717 + mmix_elf_section_data (sec)->pjs.stubs_size_sum); 2718 2719 if ((value & 3) == 0 2720 && bfd_check_overflow (complain_overflow_signed, 2721 19, 2722 0, 2723 bfd_arch_bits_per_address (abfd), 2724 value - dot 2725 - (value > dot 2726 ? mmix_elf_section_data (sec) 2727 ->pjs.stub_size[pjsno] 2728 : 0)) 2729 == bfd_reloc_ok) 2730 /* If the reloc fits, no stub is needed. */ 2731 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] = 0; 2732 else 2733 /* Maybe we can get away with just a JMP insn? */ 2734 if ((value & 3) == 0 2735 && bfd_check_overflow (complain_overflow_signed, 2736 27, 2737 0, 2738 bfd_arch_bits_per_address (abfd), 2739 value - stubaddr 2740 - (value > dot 2741 ? mmix_elf_section_data (sec) 2742 ->pjs.stub_size[pjsno] - 4 2743 : 0)) 2744 == bfd_reloc_ok) 2745 /* Yep, account for a stub consisting of a single JMP insn. */ 2746 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] = 4; 2747 else 2748 /* Nope, go for the full insn stub. It doesn't seem useful to 2749 emit the intermediate sizes; those will only be useful for 2750 a >64M program assuming contiguous code. */ 2751 mmix_elf_section_data (sec)->pjs.stub_size[pjsno] 2752 = MAX_PUSHJ_STUB_SIZE; 2753 2754 mmix_elf_section_data (sec)->pjs.stubs_size_sum 2755 += mmix_elf_section_data (sec)->pjs.stub_size[pjsno]; 2756 pjsno++; 2757 continue; 2758 } 2759 2760 /* We're looking at a R_MMIX_BASE_PLUS_OFFSET reloc. */ 2761 2762 gregdata->reloc_request[gregdata->bpo_reloc_indexes[bpono]].value 2763 = symval + irel->r_addend; 2764 gregdata->reloc_request[gregdata->bpo_reloc_indexes[bpono++]].valid = true; 2765 gregdata->n_remaining_bpo_relocs_this_relaxation_round--; 2766 } 2767 2768 /* Check if that was the last BPO-reloc. If so, sort the values and 2769 calculate how many registers we need to cover them. Set the size of 2770 the linker gregs, and if the number of registers changed, indicate 2771 that we need to relax some more because we have more work to do. */ 2772 if (gregdata != NULL 2773 && gregdata->n_remaining_bpo_relocs_this_relaxation_round == 0) 2774 { 2775 size_t i; 2776 bfd_vma prev_base; 2777 size_t regindex; 2778 2779 /* First, reset the remaining relocs for the next round. */ 2780 gregdata->n_remaining_bpo_relocs_this_relaxation_round 2781 = gregdata->n_bpo_relocs; 2782 2783 qsort (gregdata->reloc_request, 2784 gregdata->n_max_bpo_relocs, 2785 sizeof (struct bpo_reloc_request), 2786 bpo_reloc_request_sort_fn); 2787 2788 /* Recalculate indexes. When we find a change (however unlikely 2789 after the initial iteration), we know we need to relax again, 2790 since items in the GREG-array are sorted by increasing value and 2791 stored in the relaxation phase. */ 2792 for (i = 0; i < gregdata->n_max_bpo_relocs; i++) 2793 if (gregdata->bpo_reloc_indexes[gregdata->reloc_request[i].bpo_reloc_no] 2794 != i) 2795 { 2796 gregdata->bpo_reloc_indexes[gregdata->reloc_request[i].bpo_reloc_no] 2797 = i; 2798 *again = true; 2799 } 2800 2801 /* Allocate register numbers (indexing from 0). Stop at the first 2802 non-valid reloc. */ 2803 for (i = 0, regindex = 0, prev_base = gregdata->reloc_request[0].value; 2804 i < gregdata->n_bpo_relocs; 2805 i++) 2806 { 2807 if (gregdata->reloc_request[i].value > prev_base + 255) 2808 { 2809 regindex++; 2810 prev_base = gregdata->reloc_request[i].value; 2811 } 2812 gregdata->reloc_request[i].regindex = regindex; 2813 gregdata->reloc_request[i].offset 2814 = gregdata->reloc_request[i].value - prev_base; 2815 } 2816 2817 /* If it's not the same as the last time, we need to relax again, 2818 because the size of the section has changed. I'm not sure we 2819 actually need to do any adjustments since the shrinking happens 2820 at the start of this section, but better safe than sorry. */ 2821 if (gregdata->n_allocated_bpo_gregs != regindex + 1) 2822 { 2823 gregdata->n_allocated_bpo_gregs = regindex + 1; 2824 *again = true; 2825 } 2826 2827 bpo_gregs_section->size = (regindex + 1) * 8; 2828 } 2829 2830 if (isymbuf != NULL && (unsigned char *) isymbuf != symtab_hdr->contents) 2831 { 2832 if (! link_info->keep_memory) 2833 free (isymbuf); 2834 else 2835 { 2836 /* Cache the symbols for elf_link_input_bfd. */ 2837 symtab_hdr->contents = (unsigned char *) isymbuf; 2838 } 2839 } 2840 2841 BFD_ASSERT(pjsno + pjsno_undefs 2842 == mmix_elf_section_data (sec)->pjs.n_pushj_relocs); 2843 2844 if (elf_section_data (sec)->relocs != internal_relocs) 2845 free (internal_relocs); 2846 2847 if (sec->size < size + mmix_elf_section_data (sec)->pjs.stubs_size_sum) 2848 abort (); 2849 2850 if (sec->size > size + mmix_elf_section_data (sec)->pjs.stubs_size_sum) 2851 { 2852 sec->size = size + mmix_elf_section_data (sec)->pjs.stubs_size_sum; 2853 *again = true; 2854 } 2855 2856 return true; 2857 2858 error_return: 2859 if ((unsigned char *) isymbuf != symtab_hdr->contents) 2860 free (isymbuf); 2861 if (elf_section_data (sec)->relocs != internal_relocs) 2862 free (internal_relocs); 2863 return false; 2864 } 2865 2866 #define ELF_ARCH bfd_arch_mmix 2867 #define ELF_MACHINE_CODE EM_MMIX 2868 2869 /* According to mmix-doc page 36 (paragraph 45), this should be (1LL << 48LL). 2870 However, that's too much for something somewhere in the linker part of 2871 BFD; perhaps the start-address has to be a non-zero multiple of this 2872 number, or larger than this number. The symptom is that the linker 2873 complains: "warning: allocated section `.text' not in segment". We 2874 settle for 64k; the page-size used in examples is 8k. 2875 #define ELF_MAXPAGESIZE 0x10000 2876 2877 Unfortunately, this causes excessive padding in the supposedly small 2878 for-education programs that are the expected usage (where people would 2879 inspect output). We stick to 256 bytes just to have *some* default 2880 alignment. */ 2881 #define ELF_MAXPAGESIZE 0x100 2882 2883 #define TARGET_BIG_SYM mmix_elf64_vec 2884 #define TARGET_BIG_NAME "elf64-mmix" 2885 2886 #define elf_info_to_howto_rel NULL 2887 #define elf_info_to_howto mmix_info_to_howto_rela 2888 #define elf_backend_relocate_section mmix_elf_relocate_section 2889 #define elf_backend_gc_mark_hook mmix_elf_gc_mark_hook 2890 2891 #define elf_backend_link_output_symbol_hook \ 2892 mmix_elf_link_output_symbol_hook 2893 #define elf_backend_add_symbol_hook mmix_elf_add_symbol_hook 2894 2895 #define elf_backend_check_relocs mmix_elf_check_relocs 2896 #define elf_backend_symbol_processing mmix_elf_symbol_processing 2897 #define elf_backend_omit_section_dynsym _bfd_elf_omit_section_dynsym_all 2898 2899 #define bfd_elf64_bfd_copy_link_hash_symbol_type \ 2900 _bfd_generic_copy_link_hash_symbol_type 2901 2902 #define bfd_elf64_bfd_is_local_label_name \ 2903 mmix_elf_is_local_label_name 2904 2905 #define elf_backend_may_use_rel_p 0 2906 #define elf_backend_may_use_rela_p 1 2907 #define elf_backend_default_use_rela_p 1 2908 2909 #define elf_backend_can_gc_sections 1 2910 #define elf_backend_section_from_bfd_section \ 2911 mmix_elf_section_from_bfd_section 2912 2913 #define bfd_elf64_new_section_hook mmix_elf_new_section_hook 2914 #define bfd_elf64_bfd_final_link mmix_elf_final_link 2915 #define bfd_elf64_bfd_relax_section mmix_elf_relax_section 2916 2917 #include "elf64-target.h" 2918