ld/emultempl/sh64elf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
   3 #
   4 # This file is part of GLD, the Gnu Linker.
   5 #
   6 # This program is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 2 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program; if not, write to the Free Software
  18 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19 #
  20
  21 # This file is sourced from elf32.em, and defines extra sh64
  22 # specific routines.
  23 #
  24
  25 LDEMUL_AFTER_ALLOCATION=sh64_elf_${EMULATION_NAME}_after_allocation
  26 LDEMUL_BEFORE_ALLOCATION=sh64_elf_${EMULATION_NAME}_before_allocation
  27
  28 cat >>e${EMULATION_NAME}.c <<EOF
  29
  30 #include "libiberty.h"
  31 #include "libbfd.h"
  32 #include "elf-bfd.h"
  33 #include "elf/sh.h"
  34
  35 static void sh64_elf_${EMULATION_NAME}_before_allocation PARAMS ((void));
  36 static void sh64_elf_${EMULATION_NAME}_after_allocation PARAMS ((void));
  37
  38 /* Check if we need a .cranges section and create it if it's not in any
  39    input file.  It might seem better to always create it and if unneeded,
  40    discard it, but I don't find a simple way to discard it totally from
  41    the output.
  42
  43    Putting it here instead of as a elf_backend_always_size_sections hook
  44    in elf32-sh64.c, means that we have access to linker command line
  45    options here, and we can access input sections in the order in which
  46    they will be linked.  */
  47
  48 static void
  49 sh64_elf_${EMULATION_NAME}_before_allocation ()
  50 {
  51   asection *cranges;
  52   asection *osec;
  53
  54   /* Call main function; we're just extending it.  */
  55   gld${EMULATION_NAME}_before_allocation ();
  56
  57   cranges = bfd_get_section_by_name (output_bfd, SH64_CRANGES_SECTION_NAME);
  58
  59   if (cranges != NULL)
  60     {
  61       if (command_line.relax)
  62         {
  63           /* FIXME: Look through incoming sections with .cranges
  64              descriptors, build up some kind of descriptors that the
  65              relaxing function will pick up and adjust, or perhaps make it
  66              find and adjust an associated .cranges descriptor.  We could
  67              also look through incoming relocs and kill the ones marking
  68              relaxation areas, but that wouldn't be TRT.  */
  69           einfo
  70             (_("%P: Sorry, turning off relaxing: .cranges section in input.\n"));
  71           einfo (_(" A .cranges section is present in:\n"));
  72
  73           {
  74             LANG_FOR_EACH_INPUT_STATEMENT (f)
  75               {
  76                 asection *input_cranges
  77                   = bfd_get_section_by_name (f->the_bfd,
  78                                              SH64_CRANGES_SECTION_NAME);
  79                 if (input_cranges != NULL)
  80                   einfo (" %I\n", f);
  81               }
  82           }
  83
  84           command_line.relax = FALSE;
  85         }
  86
  87       /* We wouldn't need to do anything when there's already a .cranges
  88          section (and have a return here), except that we need to set the
  89          section flags right for output sections that *don't* need a
  90          .cranges section.  */
  91     }
  92
  93   if (command_line.relax)
  94     {
  95       LANG_FOR_EACH_INPUT_STATEMENT (f)
  96         {
  97           if (bfd_get_flavour (f->the_bfd) == bfd_target_elf_flavour)
  98             {
  99               asection *isec;
 100               for (isec = f->the_bfd->sections;
 101                    isec != NULL;
 102                    isec = isec->next)
 103                 {
 104                   if (elf_section_data (isec)->this_hdr.sh_flags
 105                       & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED))
 106                     {
 107                       einfo (_("%P: Sorry, turning off relaxing: SHmedia sections present.\n"));
 108                       einfo ("  %I\n", f);
 109                       command_line.relax = FALSE;
 110                       goto done_scanning_shmedia_sections;
 111                     }
 112                 }
 113             }
 114         }
 115     }
 116  done_scanning_shmedia_sections:
 117
 118   /* For each non-empty input section in each output section, check if it
 119      has the same SH64-specific flags.  If some input section differs, we
 120      need a .cranges section.  */
 121   for (osec = output_bfd->sections;
 122        osec != NULL;
 123        osec = osec->next)
 124     {
 125       struct sh64_section_data *sh64_sec_data;
 126       bfd_vma oflags_isa = 0;
 127       bfd_vma iflags_isa = 0;
 128
 129       if (bfd_get_flavour (output_bfd) != bfd_target_elf_flavour)
 130         einfo (_("%FError: non-ELF output formats are not supported by this target's linker.\n"));
 131
 132       sh64_sec_data = sh64_elf_section_data (osec);
 133
 134       /* Omit excluded or garbage-collected sections.  */
 135       if (bfd_get_section_flags (output_bfd, osec) & SEC_EXCLUDE)
 136         continue;
 137
 138       /* Make sure we have the target section data initialized.  */
 139       if (sh64_sec_data == NULL)
 140         {
 141           sh64_sec_data = xcalloc (1, sizeof (struct sh64_section_data));
 142           sh64_elf_section_data (osec) = sh64_sec_data;
 143         }
 144
 145       /* First find an input section so we have flags to compare with; the
 146          flags in the output section are not valid.  */
 147       {
 148         LANG_FOR_EACH_INPUT_STATEMENT (f)
 149           {
 150             asection *isec;
 151
 152             for (isec = f->the_bfd->sections;
 153                  isec != NULL;
 154                  isec = isec->next)
 155               {
 156                 if (isec->output_section == osec
 157                     && isec->_raw_size != 0
 158                     && (bfd_get_section_flags (isec->owner, isec)
 159                         & SEC_EXCLUDE) == 0)
 160                   {
 161                     oflags_isa
 162                       = (elf_section_data (isec)->this_hdr.sh_flags
 163                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED));
 164                     goto break_1;
 165                   }
 166               }
 167           }
 168       }
 169
 170     break_1:
 171
 172       /* Check that all input sections have the same contents-type flags
 173          as the first input section.  */
 174       {
 175         LANG_FOR_EACH_INPUT_STATEMENT (f)
 176           {
 177             asection *isec;
 178
 179             for (isec = f->the_bfd->sections;
 180                  isec != NULL;
 181                  isec = isec->next)
 182               {
 183                 if (isec->output_section == osec
 184                     && isec->_raw_size != 0
 185                     && (bfd_get_section_flags (isec->owner, isec)
 186                         & SEC_EXCLUDE) == 0)
 187                   {
 188                     iflags_isa
 189                       = (elf_section_data (isec)->this_hdr.sh_flags
 190                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED));
 191
 192                     /* If flags don't agree, we need a .cranges section.
 193                        Create it here if it did not exist through input
 194                        sections.  */
 195                     if (iflags_isa != oflags_isa)
 196                       {
 197                         if (cranges == NULL)
 198                           {
 199                             /* This section will be *appended* to
 200                                sections, so the outer iteration will reach
 201                                it in due time and set
 202                                sh64_elf_section_data; no need to set it
 203                                specifically here.  */
 204                             cranges
 205                               = bfd_make_section (output_bfd,
 206                                                   SH64_CRANGES_SECTION_NAME);
 207                             if (cranges == NULL
 208                                 || !bfd_set_section_flags (output_bfd,
 209                                                            cranges,
 210                                                            SEC_LINKER_CREATED
 211                                                            | SEC_KEEP
 212                                                            | SEC_HAS_CONTENTS
 213                                                            | SEC_DEBUGGING))
 214                               einfo
 215                                 (_("%P%E%F: Can't make .cranges section\n"));
 216                           }
 217
 218                         /* We don't need to look at more input sections,
 219                            and we know this section will have mixed
 220                            contents.  */
 221                         goto break_2;
 222                       }
 223                   }
 224               }
 225           }
 226       }
 227
 228       /* If we got here, then all input sections in this output section
 229          have the same contents flag.  Put that where we expect to see
 230          contents flags.  We don't need to do this for sections that will
 231          need additional, linker-generated .cranges entries.  */
 232       sh64_sec_data->contents_flags = iflags_isa;
 233
 234     break_2:
 235       ;
 236     }
 237 }
 238
 239 /* Size up and extend the .cranges section, merging generated entries.  */
 240
 241 static void
 242 sh64_elf_${EMULATION_NAME}_after_allocation ()
 243 {
 244   bfd_vma new_cranges = 0;
 245   bfd_vma cranges_growth = 0;
 246   asection *osec;
 247   bfd_byte *crangesp;
 248
 249   asection *cranges
 250     = bfd_get_section_by_name (output_bfd, SH64_CRANGES_SECTION_NAME);
 251
 252   /* If this ever starts doing something, we will pick it up.  */
 253   after_allocation_default ();
 254
 255   /* If there is no .cranges section, it is because it was seen earlier on
 256      that none was needed.  Otherwise it must have been created then, or
 257      be present in input.  */
 258   if (cranges == NULL)
 259     return;
 260
 261   /* First, we set the ISA flags for each output section according to the
 262      first non-discarded section.  For each input section in osec, we
 263      check if it has the same flags.  If it does not, we set flags to mark
 264      a mixed section (and exit the loop early).  */
 265   for (osec = output_bfd->sections;
 266        osec != NULL;
 267        osec = osec->next)
 268     {
 269       bfd_vma oflags_isa = 0;
 270       bfd_boolean need_check_cranges = FALSE;
 271
 272       /* Omit excluded or garbage-collected sections.  */
 273       if (bfd_get_section_flags (output_bfd, osec) & SEC_EXCLUDE)
 274         continue;
 275
 276       /* First find an input section so we have flags to compare with; the
 277          flags in the output section are not valid.  */
 278       {
 279         LANG_FOR_EACH_INPUT_STATEMENT (f)
 280           {
 281             asection *isec;
 282
 283             for (isec = f->the_bfd->sections;
 284                  isec != NULL;
 285                  isec = isec->next)
 286               {
 287                 if (isec->output_section == osec
 288                     && isec->_raw_size != 0
 289                     && (bfd_get_section_flags (isec->owner, isec)
 290                         & SEC_EXCLUDE) == 0)
 291                   {
 292                     oflags_isa
 293                       = (elf_section_data (isec)->this_hdr.sh_flags
 294                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED));
 295                     goto break_1;
 296                   }
 297               }
 298           }
 299       }
 300
 301     break_1:
 302
 303       /* Check that all input sections have the same contents-type flags
 304          as the first input section.  */
 305       {
 306         LANG_FOR_EACH_INPUT_STATEMENT (f)
 307           {
 308             asection *isec;
 309
 310             for (isec = f->the_bfd->sections;
 311                  isec != NULL;
 312                  isec = isec->next)
 313               {
 314                 if (isec->output_section == osec
 315                     && isec->_raw_size != 0
 316                     && (bfd_get_section_flags (isec->owner, isec)
 317                         & SEC_EXCLUDE) == 0)
 318                   {
 319                     bfd_vma iflags_isa
 320                       = (elf_section_data (isec)->this_hdr.sh_flags
 321                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED));
 322
 323                     /* If flags don't agree, set the target-specific data
 324                        of the section to mark that this section needs to
 325                        be have .cranges section entries added.  Don't
 326                        bother setting ELF section flags in output section;
 327                        they will be cleared later and will have to be
 328                        re-initialized before the linked file is written.  */
 329                     if (iflags_isa != oflags_isa)
 330                       {
 331                         oflags_isa = SHF_SH5_ISA32_MIXED;
 332
 333                         BFD_ASSERT (sh64_elf_section_data (osec) != NULL);
 334
 335                         sh64_elf_section_data (osec)->contents_flags
 336                           = SHF_SH5_ISA32_MIXED;
 337                         need_check_cranges = TRUE;
 338                         goto break_2;
 339                       }
 340                   }
 341               }
 342           }
 343       }
 344
 345     break_2:
 346
 347       /* If there were no new ranges for this output section, we don't
 348          need to iterate over the input sections to check how many are
 349          needed.  */
 350       if (! need_check_cranges)
 351         continue;
 352
 353       /* If we found a section with differing contents type, we need more
 354          ranges to mark the sections that are not mixed (and already have
 355          .cranges descriptors).  Calculate the maximum number of new
 356          entries here.  We may merge some of them, so that number is not
 357          final; it can shrink.  */
 358       {
 359         LANG_FOR_EACH_INPUT_STATEMENT (f)
 360           {
 361             asection *isec;
 362
 363             for (isec = f->the_bfd->sections;
 364                  isec != NULL;
 365                  isec = isec->next)
 366               {
 367                 if (isec->output_section == osec
 368                     && isec->_raw_size != 0
 369                     && (bfd_get_section_flags (isec->owner, isec)
 370                         & SEC_EXCLUDE) == 0
 371                     && ((elf_section_data (isec)->this_hdr.sh_flags
 372                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED))
 373                         != SHF_SH5_ISA32_MIXED))
 374                   new_cranges++;
 375               }
 376           }
 377       }
 378     }
 379
 380   BFD_ASSERT (cranges->contents == NULL);
 381   BFD_ASSERT (sh64_elf_section_data (cranges) != NULL);
 382
 383   /* Make sure we have .cranges in memory even if there were only
 384      assembler-generated .cranges.  */
 385   cranges_growth = new_cranges * SH64_CRANGE_SIZE;
 386   cranges->contents
 387     = (bfd_byte *) xcalloc (cranges->_raw_size + cranges_growth, 1);
 388   bfd_set_section_flags (cranges->owner, cranges,
 389                          bfd_get_section_flags (cranges->owner, cranges)
 390                          | SEC_IN_MEMORY);
 391
 392   /* If we don't need to grow the .cranges section beyond what was in the
 393      input sections, we have nothing more to do here.  We then only got
 394      here because there was a .cranges section coming from input.  Zero
 395      out the number of generated .cranges.  */
 396   if (new_cranges == 0)
 397     {
 398       sh64_elf_section_data (cranges)->cranges_growth = 0;
 399       return;
 400     }
 401
 402   crangesp = cranges->contents + cranges->_raw_size;
 403
 404   /* Now pass over the sections again, and make reloc orders for the new
 405      .cranges entries.  Constants are set as we go.  */
 406   for (osec = output_bfd->sections;
 407        osec != NULL;
 408        osec = osec->next)
 409     {
 410       struct bfd_link_order *cr_addr_order = NULL;
 411       enum sh64_elf_cr_type last_cr_type = CRT_NONE;
 412       bfd_vma last_cr_size = 0;
 413       bfd_vma continuation_vma = 0;
 414
 415       /* Omit excluded or garbage-collected sections, and output sections
 416          which were not marked as needing further processing.  */
 417       if ((bfd_get_section_flags (output_bfd, osec) & SEC_EXCLUDE) != 0
 418           || (sh64_elf_section_data (osec)->contents_flags
 419               != SHF_SH5_ISA32_MIXED))
 420         continue;
 421
 422       {
 423         LANG_FOR_EACH_INPUT_STATEMENT (f)
 424           {
 425             asection *isec;
 426
 427             for (isec = f->the_bfd->sections;
 428                  isec != NULL;
 429                  isec = isec->next)
 430               {
 431                 /* Allow only sections that have (at least initially) a
 432                    non-zero size, and are not excluded, and are not marked
 433                    as containing mixed data, thus already having .cranges
 434                    entries.  */
 435                 if (isec->output_section == osec
 436                     && isec->_raw_size != 0
 437                     && (bfd_get_section_flags (isec->owner, isec)
 438                         & SEC_EXCLUDE) == 0
 439                     && ((elf_section_data (isec)->this_hdr.sh_flags
 440                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED))
 441                         != SHF_SH5_ISA32_MIXED))
 442                   {
 443                     enum sh64_elf_cr_type cr_type;
 444                     bfd_vma cr_size;
 445                     bfd_vma isa_flags
 446                       = (elf_section_data (isec)->this_hdr.sh_flags
 447                          & (SHF_SH5_ISA32 | SHF_SH5_ISA32_MIXED));
 448
 449                     if (isa_flags == SHF_SH5_ISA32)
 450                       cr_type = CRT_SH5_ISA32;
 451                     else if ((bfd_get_section_flags (isec->owner, isec)
 452                               & SEC_CODE) == 0)
 453                       cr_type = CRT_DATA;
 454                     else
 455                       cr_type = CRT_SH5_ISA16;
 456
 457                     cr_size
 458                       = (isec->_cooked_size
 459                          ? isec->_cooked_size : isec->_raw_size);
 460
 461                     /* Sections can be empty, like .text in a file that
 462                        only contains other sections.  Ranges shouldn't be
 463                        emitted for them.  This can presumably happen after
 464                        relaxing and is not be caught at the "raw size"
 465                        test above.  */
 466                     if (cr_size == 0)
 467                       continue;
 468
 469                     /* See if this is a continuation of the previous range
 470                        for the same output section.  If so, just change
 471                        the size of the last range and continue.  */
 472                     if (cr_type == last_cr_type
 473                         && (continuation_vma
 474                             == osec->vma + isec->output_offset))
 475                       {
 476                         last_cr_size += cr_size;
 477                         bfd_put_32 (output_bfd, last_cr_size,
 478                                     crangesp - SH64_CRANGE_SIZE
 479                                     + SH64_CRANGE_CR_SIZE_OFFSET);
 480
 481                         continuation_vma += cr_size;
 482                         continue;
 483                       }
 484
 485                     /* If we emit relocateable contents, we need a
 486                        relocation for the start address.  */
 487                     if (link_info.relocateable || link_info.emitrelocations)
 488                       {
 489                         /* FIXME: We could perhaps use lang_add_reloc and
 490                            friends here, but I'm not really sure that
 491                            would leave us free to do some optimizations
 492                            later.  */
 493                         cr_addr_order
 494                           = bfd_new_link_order (output_bfd, cranges);
 495
 496                         if (cr_addr_order == NULL)
 497                           {
 498                             einfo (_("%P%F: bfd_new_link_order failed\n"));
 499                             return;
 500                           }
 501
 502                         cr_addr_order->type = bfd_section_reloc_link_order;
 503                         cr_addr_order->offset
 504                           = (cranges->output_offset
 505                              + crangesp + SH64_CRANGE_CR_ADDR_OFFSET
 506                              - cranges->contents);
 507                         cr_addr_order->size = 4;
 508                         cr_addr_order->u.reloc.p
 509                           = ((struct bfd_link_order_reloc *)
 510                              xmalloc (sizeof (struct bfd_link_order_reloc)));
 511
 512                         cr_addr_order->u.reloc.p->reloc = BFD_RELOC_32;
 513                         cr_addr_order->u.reloc.p->u.section = osec;
 514
 515                         /* Since SH, unlike normal RELA-targets, uses a
 516                            "partial inplace" REL-like relocation for this,
 517                            we put the addend in the contents and specify 0
 518                            for the reloc.  */
 519                         bfd_put_32 (output_bfd, isec->output_offset,
 520                                     crangesp + SH64_CRANGE_CR_ADDR_OFFSET);
 521                         cr_addr_order->u.reloc.p->addend = 0;
 522
 523                         /* We must update the number of relocations here,
 524                            since the elf linker does not take link orders
 525                            into account when setting header sizes.  The
 526                            actual relocation orders are however executed
 527                            correctly.  */
 528                         elf_section_data(cranges)->rel_count++;
 529                       }
 530                     else
 531                       bfd_put_32 (output_bfd,
 532                                   osec->vma + isec->output_offset,
 533                                   crangesp + SH64_CRANGE_CR_ADDR_OFFSET);
 534
 535                     /* If we could make a reloc for cr_size we would do
 536                        it, but we would have to have a symbol for the size
 537                        of the _input_ section and there's no way to
 538                        generate that.  */
 539                     bfd_put_32 (output_bfd, cr_size,
 540                                 crangesp + SH64_CRANGE_CR_SIZE_OFFSET);
 541
 542                     bfd_put_16 (output_bfd, (bfd_vma) cr_type,
 543                                 crangesp + SH64_CRANGE_CR_TYPE_OFFSET);
 544
 545                     last_cr_type = cr_type;
 546                     last_cr_size = cr_size;
 547                     continuation_vma
 548                       = osec->vma + isec->output_offset + cr_size;
 549                     crangesp += SH64_CRANGE_SIZE;
 550                   }
 551               }
 552           }
 553       }
 554     }
 555
 556   /* The .cranges section will have this size, no larger or smaller.
 557      Since relocs (if relocateable linking) will be emitted into the
 558      "extended" size, we must set the raw size to the total.  We have to
 559      keep track of the number of new .cranges entries.
 560
 561      Sorting before writing is done by sh64_elf_final_write_processing.  */
 562
 563   cranges->_cooked_size = crangesp - cranges->contents;
 564   sh64_elf_section_data (cranges)->cranges_growth
 565     = cranges->_cooked_size - cranges->_raw_size;
 566   cranges->_raw_size = cranges->_cooked_size;
 567 }