gdb/compile/compile-object-load.c

   1 /* Load module for 'compile' command.
   2
   3    Copyright (C) 2014-2021 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "compile-object-load.h"
  22 #include "compile-internal.h"
  23 #include "command.h"
  24 #include "objfiles.h"
  25 #include "gdbcore.h"
  26 #include "readline/tilde.h"
  27 #include "bfdlink.h"
  28 #include "gdbcmd.h"
  29 #include "regcache.h"
  30 #include "inferior.h"
  31 #include "gdbthread.h"
  32 #include "compile.h"
  33 #include "block.h"
  34 #include "arch-utils.h"
  35 #include <algorithm>
  36
  37 /* Add inferior mmap memory range ADDR..ADDR+SIZE (exclusive) to the
  38    list.  */
  39
  40 void
  41 munmap_list::add (CORE_ADDR addr, CORE_ADDR size)
  42 {
  43   struct munmap_item item = { addr, size };
  44   items.push_back (item);
  45 }
  46
  47 /* Destroy an munmap_list.  */
  48
  49 munmap_list::~munmap_list ()
  50 {
  51   for (auto &item : items)
  52     {
  53       try
  54         {
  55           gdbarch_infcall_munmap (target_gdbarch (), item.addr, item.size);
  56         }
  57       catch (const gdb_exception_error &ex)
  58         {
  59           /* There's not much the user can do, so just ignore
  60              this.  */
  61         }
  62     }
  63 }
  64
  65 /* A data structure that is used to lay out sections of our objfile in
  66    inferior memory.  */
  67
  68 struct setup_sections_data
  69 {
  70   explicit setup_sections_data (bfd *abfd)
  71     : m_bfd (abfd),
  72       m_last_section_first (abfd->sections)
  73   {
  74   }
  75
  76   /* Place all ABFD sections next to each other obeying all
  77      constraints.  */
  78   void setup_one_section (asection *sect);
  79
  80   /* List of inferior mmap ranges where setup_sections should add its
  81      next range.  */
  82   struct munmap_list munmap_list;
  83
  84 private:
  85
  86   /* The BFD.  */
  87   bfd *m_bfd;
  88
  89   /* Size of all recent sections with matching LAST_PROT.  */
  90   CORE_ADDR m_last_size = 0;
  91
  92   /* First section matching LAST_PROT.  */
  93   asection *m_last_section_first;
  94
  95   /* Memory protection like the prot parameter of gdbarch_infcall_mmap. */
  96   unsigned m_last_prot = -1;
  97
  98   /* Maximum of alignments of all sections matching LAST_PROT.
  99      This value is always at least 1.  This value is always a power of 2.  */
 100   CORE_ADDR m_last_max_alignment = -1;
 101
 102 };
 103
 104 /* See setup_sections_data.  */
 105
 106 void
 107 setup_sections_data::setup_one_section (asection *sect)
 108 {
 109   CORE_ADDR alignment;
 110   unsigned prot;
 111
 112   if (sect != NULL)
 113     {
 114       /* It is required by later bfd_get_relocated_section_contents.  */
 115       if (sect->output_section == NULL)
 116         sect->output_section = sect;
 117
 118       if ((bfd_section_flags (sect) & SEC_ALLOC) == 0)
 119         return;
 120
 121       /* Make the memory always readable.  */
 122       prot = GDB_MMAP_PROT_READ;
 123       if ((bfd_section_flags (sect) & SEC_READONLY) == 0)
 124         prot |= GDB_MMAP_PROT_WRITE;
 125       if ((bfd_section_flags (sect) & SEC_CODE) != 0)
 126         prot |= GDB_MMAP_PROT_EXEC;
 127
 128       if (compile_debug)
 129         fprintf_unfiltered (gdb_stdlog,
 130                             "module \"%s\" section \"%s\" size %s prot %u\n",
 131                             bfd_get_filename (m_bfd),
 132                             bfd_section_name (sect),
 133                             paddress (target_gdbarch (),
 134                                       bfd_section_size (sect)),
 135                             prot);
 136     }
 137   else
 138     prot = -1;
 139
 140   if (sect == NULL
 141       || (m_last_prot != prot && bfd_section_size (sect) != 0))
 142     {
 143       CORE_ADDR addr;
 144       asection *sect_iter;
 145
 146       if (m_last_size != 0)
 147         {
 148           addr = gdbarch_infcall_mmap (target_gdbarch (), m_last_size,
 149                                        m_last_prot);
 150           munmap_list.add (addr, m_last_size);
 151           if (compile_debug)
 152             fprintf_unfiltered (gdb_stdlog,
 153                                 "allocated %s bytes at %s prot %u\n",
 154                                 paddress (target_gdbarch (), m_last_size),
 155                                 paddress (target_gdbarch (), addr),
 156                                 m_last_prot);
 157         }
 158       else
 159         addr = 0;
 160
 161       if ((addr & (m_last_max_alignment - 1)) != 0)
 162         error (_("Inferior compiled module address %s "
 163                  "is not aligned to BFD required %s."),
 164                paddress (target_gdbarch (), addr),
 165                paddress (target_gdbarch (), m_last_max_alignment));
 166
 167       for (sect_iter = m_last_section_first; sect_iter != sect;
 168            sect_iter = sect_iter->next)
 169         if ((bfd_section_flags (sect_iter) & SEC_ALLOC) != 0)
 170           bfd_set_section_vma (sect_iter, addr + bfd_section_vma (sect_iter));
 171
 172       m_last_size = 0;
 173       m_last_section_first = sect;
 174       m_last_prot = prot;
 175       m_last_max_alignment = 1;
 176     }
 177
 178   if (sect == NULL)
 179     return;
 180
 181   alignment = ((CORE_ADDR) 1) << bfd_section_alignment (sect);
 182   m_last_max_alignment = std::max (m_last_max_alignment, alignment);
 183
 184   m_last_size = (m_last_size + alignment - 1) & -alignment;
 185
 186   bfd_set_section_vma (sect, m_last_size);
 187
 188   m_last_size += bfd_section_size (sect);
 189   m_last_size = (m_last_size + alignment - 1) & -alignment;
 190 }
 191
 192 /* Helper for link_callbacks callbacks vector.  */
 193
 194 static void
 195 link_callbacks_multiple_definition (struct bfd_link_info *link_info,
 196                                     struct bfd_link_hash_entry *h, bfd *nbfd,
 197                                     asection *nsec, bfd_vma nval)
 198 {
 199   bfd *abfd = link_info->input_bfds;
 200
 201   if (link_info->allow_multiple_definition)
 202     return;
 203   warning (_("Compiled module \"%s\": multiple symbol definitions: %s"),
 204            bfd_get_filename (abfd), h->root.string);
 205 }
 206
 207 /* Helper for link_callbacks callbacks vector.  */
 208
 209 static void
 210 link_callbacks_warning (struct bfd_link_info *link_info, const char *xwarning,
 211                         const char *symbol, bfd *abfd, asection *section,
 212                         bfd_vma address)
 213 {
 214   warning (_("Compiled module \"%s\" section \"%s\": warning: %s"),
 215            bfd_get_filename (abfd), bfd_section_name (section),
 216            xwarning);
 217 }
 218
 219 /* Helper for link_callbacks callbacks vector.  */
 220
 221 static void
 222 link_callbacks_undefined_symbol (struct bfd_link_info *link_info,
 223                                  const char *name, bfd *abfd, asection *section,
 224                                  bfd_vma address, bfd_boolean is_fatal)
 225 {
 226   warning (_("Cannot resolve relocation to \"%s\" "
 227              "from compiled module \"%s\" section \"%s\"."),
 228            name, bfd_get_filename (abfd), bfd_section_name (section));
 229 }
 230
 231 /* Helper for link_callbacks callbacks vector.  */
 232
 233 static void
 234 link_callbacks_reloc_overflow (struct bfd_link_info *link_info,
 235                                struct bfd_link_hash_entry *entry,
 236                                const char *name, const char *reloc_name,
 237                                bfd_vma addend, bfd *abfd, asection *section,
 238                                bfd_vma address)
 239 {
 240 }
 241
 242 /* Helper for link_callbacks callbacks vector.  */
 243
 244 static void
 245 link_callbacks_reloc_dangerous (struct bfd_link_info *link_info,
 246                                 const char *message, bfd *abfd,
 247                                 asection *section, bfd_vma address)
 248 {
 249   warning (_("Compiled module \"%s\" section \"%s\": dangerous "
 250              "relocation: %s\n"),
 251            bfd_get_filename (abfd), bfd_section_name (section),
 252            message);
 253 }
 254
 255 /* Helper for link_callbacks callbacks vector.  */
 256
 257 static void
 258 link_callbacks_unattached_reloc (struct bfd_link_info *link_info,
 259                                  const char *name, bfd *abfd, asection *section,
 260                                  bfd_vma address)
 261 {
 262   warning (_("Compiled module \"%s\" section \"%s\": unattached "
 263              "relocation: %s\n"),
 264            bfd_get_filename (abfd), bfd_section_name (section),
 265            name);
 266 }
 267
 268 /* Helper for link_callbacks callbacks vector.  */
 269
 270 static void link_callbacks_einfo (const char *fmt, ...)
 271   ATTRIBUTE_PRINTF (1, 2);
 272
 273 static void
 274 link_callbacks_einfo (const char *fmt, ...)
 275 {
 276   va_list ap;
 277
 278   va_start (ap, fmt);
 279   std::string str = string_vprintf (fmt, ap);
 280   va_end (ap);
 281
 282   warning (_("Compile module: warning: %s"), str.c_str ());
 283 }
 284
 285 /* Helper for bfd_get_relocated_section_contents.
 286    Only these symbols are set by bfd_simple_get_relocated_section_contents
 287    but bfd/ seems to use even the NULL ones without checking them first.  */
 288
 289 static const struct bfd_link_callbacks link_callbacks =
 290 {
 291   NULL, /* add_archive_element */
 292   link_callbacks_multiple_definition, /* multiple_definition */
 293   NULL, /* multiple_common */
 294   NULL, /* add_to_set */
 295   NULL, /* constructor */
 296   link_callbacks_warning, /* warning */
 297   link_callbacks_undefined_symbol, /* undefined_symbol */
 298   link_callbacks_reloc_overflow, /* reloc_overflow */
 299   link_callbacks_reloc_dangerous, /* reloc_dangerous */
 300   link_callbacks_unattached_reloc, /* unattached_reloc */
 301   NULL, /* notice */
 302   link_callbacks_einfo, /* einfo */
 303   NULL, /* info */
 304   NULL, /* minfo */
 305   NULL, /* override_segment_assignment */
 306 };
 307
 308 struct link_hash_table_cleanup_data
 309 {
 310   explicit link_hash_table_cleanup_data (bfd *abfd_)
 311     : abfd (abfd_),
 312       link_next (abfd->link.next)
 313   {
 314   }
 315
 316   ~link_hash_table_cleanup_data ()
 317   {
 318     if (abfd->is_linker_output)
 319       (*abfd->link.hash->hash_table_free) (abfd);
 320     abfd->link.next = link_next;
 321   }
 322
 323   DISABLE_COPY_AND_ASSIGN (link_hash_table_cleanup_data);
 324
 325 private:
 326
 327   bfd *abfd;
 328   bfd *link_next;
 329 };
 330
 331 /* Relocate and store into inferior memory each section SECT of ABFD.  */
 332
 333 static void
 334 copy_sections (bfd *abfd, asection *sect, void *data)
 335 {
 336   asymbol **symbol_table = (asymbol **) data;
 337   bfd_byte *sect_data_got;
 338   struct bfd_link_info link_info;
 339   struct bfd_link_order link_order;
 340   CORE_ADDR inferior_addr;
 341
 342   if ((bfd_section_flags (sect) & (SEC_ALLOC | SEC_LOAD))
 343       != (SEC_ALLOC | SEC_LOAD))
 344     return;
 345
 346   if (bfd_section_size (sect) == 0)
 347     return;
 348
 349   /* Mostly a copy of bfd_simple_get_relocated_section_contents which GDB
 350      cannot use as it does not report relocations to undefined symbols.  */
 351   memset (&link_info, 0, sizeof (link_info));
 352   link_info.output_bfd = abfd;
 353   link_info.input_bfds = abfd;
 354   link_info.input_bfds_tail = &abfd->link.next;
 355
 356   struct link_hash_table_cleanup_data cleanup_data (abfd);
 357
 358   abfd->link.next = NULL;
 359   link_info.hash = bfd_link_hash_table_create (abfd);
 360
 361   link_info.callbacks = &link_callbacks;
 362
 363   memset (&link_order, 0, sizeof (link_order));
 364   link_order.next = NULL;
 365   link_order.type = bfd_indirect_link_order;
 366   link_order.offset = 0;
 367   link_order.size = bfd_section_size (sect);
 368   link_order.u.indirect.section = sect;
 369
 370   gdb::unique_xmalloc_ptr<gdb_byte> sect_data
 371     ((bfd_byte *) xmalloc (bfd_section_size (sect)));
 372
 373   sect_data_got = bfd_get_relocated_section_contents (abfd, &link_info,
 374                                                       &link_order,
 375                                                       sect_data.get (),
 376                                                       FALSE, symbol_table);
 377
 378   if (sect_data_got == NULL)
 379     error (_("Cannot map compiled module \"%s\" section \"%s\": %s"),
 380            bfd_get_filename (abfd), bfd_section_name (sect),
 381            bfd_errmsg (bfd_get_error ()));
 382   gdb_assert (sect_data_got == sect_data.get ());
 383
 384   inferior_addr = bfd_section_vma (sect);
 385   if (0 != target_write_memory (inferior_addr, sect_data.get (),
 386                                 bfd_section_size (sect)))
 387     error (_("Cannot write compiled module \"%s\" section \"%s\" "
 388              "to inferior memory range %s-%s."),
 389            bfd_get_filename (abfd), bfd_section_name (sect),
 390            paddress (target_gdbarch (), inferior_addr),
 391            paddress (target_gdbarch (),
 392                      inferior_addr + bfd_section_size (sect)));
 393 }
 394
 395 /* Fetch the type of COMPILE_I_EXPR_PTR_TYPE and COMPILE_I_EXPR_VAL
 396    symbols in OBJFILE so we can calculate how much memory to allocate
 397    for the out parameter.  This avoids needing a malloc in the generated
 398    code.  Throw an error if anything fails.
 399    GDB first tries to compile the code with COMPILE_I_PRINT_ADDRESS_SCOPE.
 400    If it finds user tries to print an array type this function returns
 401    NULL.  Caller will then regenerate the code with
 402    COMPILE_I_PRINT_VALUE_SCOPE, recompiles it again and finally runs it.
 403    This is because __auto_type array-to-pointer type conversion of
 404    COMPILE_I_EXPR_VAL which gets detected by COMPILE_I_EXPR_PTR_TYPE
 405    preserving the array type.  */
 406
 407 static struct type *
 408 get_out_value_type (struct symbol *func_sym, struct objfile *objfile,
 409                     enum compile_i_scope_types scope)
 410 {
 411   struct symbol *gdb_ptr_type_sym;
 412   /* Initialize it just to avoid a GCC false warning.  */
 413   struct symbol *gdb_val_sym = NULL;
 414   struct type *gdb_ptr_type, *gdb_type_from_ptr, *gdb_type, *retval;
 415   /* Initialize it just to avoid a GCC false warning.  */
 416   const struct block *block = NULL;
 417   const struct blockvector *bv;
 418   int nblocks = 0;
 419   int block_loop = 0;
 420
 421   lookup_name_info func_matcher (GCC_FE_WRAPPER_FUNCTION,
 422                                  symbol_name_match_type::SEARCH_NAME);
 423
 424   bv = SYMTAB_BLOCKVECTOR (func_sym->owner.symtab);
 425   nblocks = BLOCKVECTOR_NBLOCKS (bv);
 426
 427   gdb_ptr_type_sym = NULL;
 428   for (block_loop = 0; block_loop < nblocks; block_loop++)
 429     {
 430       struct symbol *function = NULL;
 431       const struct block *function_block;
 432
 433       block = BLOCKVECTOR_BLOCK (bv, block_loop);
 434       if (BLOCK_FUNCTION (block) != NULL)
 435         continue;
 436       gdb_val_sym = block_lookup_symbol (block,
 437                                          COMPILE_I_EXPR_VAL,
 438                                          symbol_name_match_type::SEARCH_NAME,
 439                                          VAR_DOMAIN);
 440       if (gdb_val_sym == NULL)
 441         continue;
 442
 443       function_block = block;
 444       while (function_block != BLOCKVECTOR_BLOCK (bv, STATIC_BLOCK)
 445              && function_block != BLOCKVECTOR_BLOCK (bv, GLOBAL_BLOCK))
 446         {
 447           function_block = BLOCK_SUPERBLOCK (function_block);
 448           function = BLOCK_FUNCTION (function_block);
 449           if (function != NULL)
 450             break;
 451         }
 452       if (function != NULL
 453           && (BLOCK_SUPERBLOCK (function_block)
 454               == BLOCKVECTOR_BLOCK (bv, STATIC_BLOCK))
 455           && symbol_matches_search_name (function, func_matcher))
 456         break;
 457     }
 458   if (block_loop == nblocks)
 459     error (_("No \"%s\" symbol found"), COMPILE_I_EXPR_VAL);
 460
 461   gdb_type = SYMBOL_TYPE (gdb_val_sym);
 462   gdb_type = check_typedef (gdb_type);
 463
 464   gdb_ptr_type_sym = block_lookup_symbol (block, COMPILE_I_EXPR_PTR_TYPE,
 465                                           symbol_name_match_type::SEARCH_NAME,
 466                                           VAR_DOMAIN);
 467   if (gdb_ptr_type_sym == NULL)
 468     error (_("No \"%s\" symbol found"), COMPILE_I_EXPR_PTR_TYPE);
 469   gdb_ptr_type = SYMBOL_TYPE (gdb_ptr_type_sym);
 470   gdb_ptr_type = check_typedef (gdb_ptr_type);
 471   if (gdb_ptr_type->code () != TYPE_CODE_PTR)
 472     error (_("Type of \"%s\" is not a pointer"), COMPILE_I_EXPR_PTR_TYPE);
 473   gdb_type_from_ptr = check_typedef (TYPE_TARGET_TYPE (gdb_ptr_type));
 474
 475   if (types_deeply_equal (gdb_type, gdb_type_from_ptr))
 476     {
 477       if (scope != COMPILE_I_PRINT_ADDRESS_SCOPE)
 478         error (_("Expected address scope in compiled module \"%s\"."),
 479                objfile_name (objfile));
 480       return gdb_type;
 481     }
 482
 483   if (gdb_type->code () != TYPE_CODE_PTR)
 484     error (_("Invalid type code %d of symbol \"%s\" "
 485              "in compiled module \"%s\"."),
 486            gdb_type_from_ptr->code (), COMPILE_I_EXPR_VAL,
 487            objfile_name (objfile));
 488
 489   retval = gdb_type_from_ptr;
 490   switch (gdb_type_from_ptr->code ())
 491     {
 492     case TYPE_CODE_ARRAY:
 493       gdb_type_from_ptr = TYPE_TARGET_TYPE (gdb_type_from_ptr);
 494       break;
 495     case TYPE_CODE_FUNC:
 496       break;
 497     default:
 498       error (_("Invalid type code %d of symbol \"%s\" "
 499                "in compiled module \"%s\"."),
 500              gdb_type_from_ptr->code (), COMPILE_I_EXPR_PTR_TYPE,
 501              objfile_name (objfile));
 502     }
 503   if (!types_deeply_equal (gdb_type_from_ptr,
 504                            TYPE_TARGET_TYPE (gdb_type)))
 505     error (_("Referenced types do not match for symbols \"%s\" and \"%s\" "
 506              "in compiled module \"%s\"."),
 507            COMPILE_I_EXPR_PTR_TYPE, COMPILE_I_EXPR_VAL,
 508            objfile_name (objfile));
 509   if (scope == COMPILE_I_PRINT_ADDRESS_SCOPE)
 510     return NULL;
 511   return retval;
 512 }
 513
 514 /* Fetch the type of first parameter of FUNC_SYM.
 515    Return NULL if FUNC_SYM has no parameters.  Throw an error otherwise.  */
 516
 517 static struct type *
 518 get_regs_type (struct symbol *func_sym, struct objfile *objfile)
 519 {
 520   struct type *func_type = SYMBOL_TYPE (func_sym);
 521   struct type *regsp_type, *regs_type;
 522
 523   /* No register parameter present.  */
 524   if (func_type->num_fields () == 0)
 525     return NULL;
 526
 527   regsp_type = check_typedef (func_type->field (0).type ());
 528   if (regsp_type->code () != TYPE_CODE_PTR)
 529     error (_("Invalid type code %d of first parameter of function \"%s\" "
 530              "in compiled module \"%s\"."),
 531            regsp_type->code (), GCC_FE_WRAPPER_FUNCTION,
 532            objfile_name (objfile));
 533
 534   regs_type = check_typedef (TYPE_TARGET_TYPE (regsp_type));
 535   if (regs_type->code () != TYPE_CODE_STRUCT)
 536     error (_("Invalid type code %d of dereferenced first parameter "
 537              "of function \"%s\" in compiled module \"%s\"."),
 538            regs_type->code (), GCC_FE_WRAPPER_FUNCTION,
 539            objfile_name (objfile));
 540
 541   return regs_type;
 542 }
 543
 544 /* Store all inferior registers required by REGS_TYPE to inferior memory
 545    starting at inferior address REGS_BASE.  */
 546
 547 static void
 548 store_regs (struct type *regs_type, CORE_ADDR regs_base)
 549 {
 550   struct gdbarch *gdbarch = target_gdbarch ();
 551   int fieldno;
 552
 553   for (fieldno = 0; fieldno < regs_type->num_fields (); fieldno++)
 554     {
 555       const char *reg_name = TYPE_FIELD_NAME (regs_type, fieldno);
 556       ULONGEST reg_bitpos = TYPE_FIELD_BITPOS (regs_type, fieldno);
 557       ULONGEST reg_bitsize = TYPE_FIELD_BITSIZE (regs_type, fieldno);
 558       ULONGEST reg_offset;
 559       struct type *reg_type
 560         = check_typedef (regs_type->field (fieldno).type ());
 561       ULONGEST reg_size = TYPE_LENGTH (reg_type);
 562       int regnum;
 563       struct value *regval;
 564       CORE_ADDR inferior_addr;
 565
 566       if (strcmp (reg_name, COMPILE_I_SIMPLE_REGISTER_DUMMY) == 0)
 567         continue;
 568
 569       if ((reg_bitpos % 8) != 0 || reg_bitsize != 0)
 570         error (_("Invalid register \"%s\" position %s bits or size %s bits"),
 571                reg_name, pulongest (reg_bitpos), pulongest (reg_bitsize));
 572       reg_offset = reg_bitpos / 8;
 573
 574       if (reg_type->code () != TYPE_CODE_INT
 575           && reg_type->code () != TYPE_CODE_PTR)
 576         error (_("Invalid register \"%s\" type code %d"), reg_name,
 577                reg_type->code ());
 578
 579       regnum = compile_register_name_demangle (gdbarch, reg_name);
 580
 581       regval = value_from_register (reg_type, regnum, get_current_frame ());
 582       if (value_optimized_out (regval))
 583         error (_("Register \"%s\" is optimized out."), reg_name);
 584       if (!value_entirely_available (regval))
 585         error (_("Register \"%s\" is not available."), reg_name);
 586
 587       inferior_addr = regs_base + reg_offset;
 588       if (0 != target_write_memory (inferior_addr, value_contents (regval),
 589                                     reg_size))
 590         error (_("Cannot write register \"%s\" to inferior memory at %s."),
 591                reg_name, paddress (gdbarch, inferior_addr));
 592     }
 593 }
 594
 595 /* Load the object file specified in FILE_NAMES into inferior memory.
 596    Throw an error otherwise.  Caller must fully dispose the return
 597    value by calling compile_object_run.  Returns NULL only for
 598    COMPILE_I_PRINT_ADDRESS_SCOPE when COMPILE_I_PRINT_VALUE_SCOPE
 599    should have been used instead.  */
 600
 601 compile_module_up
 602 compile_object_load (const compile_file_names &file_names,
 603                      enum compile_i_scope_types scope, void *scope_data)
 604 {
 605   CORE_ADDR regs_addr, out_value_addr = 0;
 606   struct symbol *func_sym;
 607   struct type *func_type;
 608   struct bound_minimal_symbol bmsym;
 609   long storage_needed;
 610   asymbol **symbol_table, **symp;
 611   long number_of_symbols, missing_symbols;
 612   struct type *regs_type, *out_value_type = NULL;
 613   char **matching;
 614   struct objfile *objfile;
 615   int expect_parameters;
 616   struct type *expect_return_type;
 617
 618   gdb::unique_xmalloc_ptr<char> filename
 619     (tilde_expand (file_names.object_file ()));
 620
 621   gdb_bfd_ref_ptr abfd (gdb_bfd_open (filename.get (), gnutarget));
 622   if (abfd == NULL)
 623     error (_("\"%s\": could not open as compiled module: %s"),
 624           filename.get (), bfd_errmsg (bfd_get_error ()));
 625
 626   if (!bfd_check_format_matches (abfd.get (), bfd_object, &matching))
 627     error (_("\"%s\": not in loadable format: %s"),
 628            filename.get (),
 629            gdb_bfd_errmsg (bfd_get_error (), matching).c_str ());
 630
 631   if ((bfd_get_file_flags (abfd.get ()) & (EXEC_P | DYNAMIC)) != 0)
 632     error (_("\"%s\": not in object format."), filename.get ());
 633
 634   struct setup_sections_data setup_sections_data (abfd.get ());
 635   for (asection *sect = abfd->sections; sect != nullptr; sect = sect->next)
 636     setup_sections_data.setup_one_section (sect);
 637   setup_sections_data.setup_one_section (nullptr);
 638
 639   storage_needed = bfd_get_symtab_upper_bound (abfd.get ());
 640   if (storage_needed < 0)
 641     error (_("Cannot read symbols of compiled module \"%s\": %s"),
 642            filename.get (), bfd_errmsg (bfd_get_error ()));
 643
 644   /* SYMFILE_VERBOSE is not passed even if FROM_TTY, user is not interested in
 645      "Reading symbols from ..." message for automatically generated file.  */
 646   objfile_up objfile_holder (symbol_file_add_from_bfd (abfd.get (),
 647                                                        filename.get (),
 648                                                        0, NULL, 0, NULL));
 649   objfile = objfile_holder.get ();
 650
 651   func_sym = lookup_global_symbol_from_objfile (objfile,
 652                                                 GLOBAL_BLOCK,
 653                                                 GCC_FE_WRAPPER_FUNCTION,
 654                                                 VAR_DOMAIN).symbol;
 655   if (func_sym == NULL)
 656     error (_("Cannot find function \"%s\" in compiled module \"%s\"."),
 657            GCC_FE_WRAPPER_FUNCTION, objfile_name (objfile));
 658   func_type = SYMBOL_TYPE (func_sym);
 659   if (func_type->code () != TYPE_CODE_FUNC)
 660     error (_("Invalid type code %d of function \"%s\" in compiled "
 661              "module \"%s\"."),
 662            func_type->code (), GCC_FE_WRAPPER_FUNCTION,
 663            objfile_name (objfile));
 664
 665   switch (scope)
 666     {
 667     case COMPILE_I_SIMPLE_SCOPE:
 668       expect_parameters = 1;
 669       expect_return_type = builtin_type (target_gdbarch ())->builtin_void;
 670       break;
 671     case COMPILE_I_RAW_SCOPE:
 672       expect_parameters = 0;
 673       expect_return_type = builtin_type (target_gdbarch ())->builtin_void;
 674       break;
 675     case COMPILE_I_PRINT_ADDRESS_SCOPE:
 676     case COMPILE_I_PRINT_VALUE_SCOPE:
 677       expect_parameters = 2;
 678       expect_return_type = builtin_type (target_gdbarch ())->builtin_void;
 679       break;
 680     default:
 681       internal_error (__FILE__, __LINE__, _("invalid scope %d"), scope);
 682     }
 683   if (func_type->num_fields () != expect_parameters)
 684     error (_("Invalid %d parameters of function \"%s\" in compiled "
 685              "module \"%s\"."),
 686            func_type->num_fields (), GCC_FE_WRAPPER_FUNCTION,
 687            objfile_name (objfile));
 688   if (!types_deeply_equal (expect_return_type, TYPE_TARGET_TYPE (func_type)))
 689     error (_("Invalid return type of function \"%s\" in compiled "
 690              "module \"%s\"."),
 691            GCC_FE_WRAPPER_FUNCTION, objfile_name (objfile));
 692
 693   /* The memory may be later needed
 694      by bfd_generic_get_relocated_section_contents
 695      called from default_symfile_relocate.  */
 696   symbol_table = (asymbol **) obstack_alloc (&objfile->objfile_obstack,
 697                                              storage_needed);
 698   number_of_symbols = bfd_canonicalize_symtab (abfd.get (), symbol_table);
 699   if (number_of_symbols < 0)
 700     error (_("Cannot parse symbols of compiled module \"%s\": %s"),
 701            filename.get (), bfd_errmsg (bfd_get_error ()));
 702
 703   missing_symbols = 0;
 704   for (symp = symbol_table; symp < symbol_table + number_of_symbols; symp++)
 705     {
 706       asymbol *sym = *symp;
 707
 708       if (sym->flags != 0)
 709         continue;
 710       sym->flags = BSF_GLOBAL;
 711       sym->section = bfd_abs_section_ptr;
 712       if (strcmp (sym->name, "_GLOBAL_OFFSET_TABLE_") == 0)
 713         {
 714           if (compile_debug)
 715             fprintf_unfiltered (gdb_stdlog,
 716                                 "ELF symbol \"%s\" relocated to zero\n",
 717                                 sym->name);
 718
 719           /* It seems to be a GCC bug, with -mcmodel=large there should be no
 720              need for _GLOBAL_OFFSET_TABLE_.  Together with -fPIE the data
 721              remain PC-relative even with _GLOBAL_OFFSET_TABLE_ as zero.  */
 722           sym->value = 0;
 723           continue;
 724         }
 725       bmsym = lookup_minimal_symbol (sym->name, NULL, NULL);
 726       switch (bmsym.minsym == NULL
 727               ? mst_unknown : MSYMBOL_TYPE (bmsym.minsym))
 728         {
 729         case mst_text:
 730         case mst_bss:
 731         case mst_data:
 732           sym->value = BMSYMBOL_VALUE_ADDRESS (bmsym);
 733           if (compile_debug)
 734             fprintf_unfiltered (gdb_stdlog,
 735                                 "ELF mst_text symbol \"%s\" relocated to %s\n",
 736                                 sym->name,
 737                                 paddress (target_gdbarch (), sym->value));
 738           break;
 739         case mst_text_gnu_ifunc:
 740           sym->value = gnu_ifunc_resolve_addr (target_gdbarch (),
 741                                                BMSYMBOL_VALUE_ADDRESS (bmsym));
 742           if (compile_debug)
 743             fprintf_unfiltered (gdb_stdlog,
 744                                 "ELF mst_text_gnu_ifunc symbol \"%s\" "
 745                                 "relocated to %s\n",
 746                                 sym->name,
 747                                 paddress (target_gdbarch (), sym->value));
 748           break;
 749         default:
 750           warning (_("Could not find symbol \"%s\" "
 751                      "for compiled module \"%s\"."),
 752                    sym->name, filename.get ());
 753           missing_symbols++;
 754         }
 755     }
 756   if (missing_symbols)
 757     error (_("%ld symbols were missing, cannot continue."), missing_symbols);
 758
 759   bfd_map_over_sections (abfd.get (), copy_sections, symbol_table);
 760
 761   regs_type = get_regs_type (func_sym, objfile);
 762   if (regs_type == NULL)
 763     regs_addr = 0;
 764   else
 765     {
 766       /* Use read-only non-executable memory protection.  */
 767       regs_addr = gdbarch_infcall_mmap (target_gdbarch (),
 768                                         TYPE_LENGTH (regs_type),
 769                                         GDB_MMAP_PROT_READ);
 770       gdb_assert (regs_addr != 0);
 771       setup_sections_data.munmap_list.add (regs_addr, TYPE_LENGTH (regs_type));
 772       if (compile_debug)
 773         fprintf_unfiltered (gdb_stdlog,
 774                             "allocated %s bytes at %s for registers\n",
 775                             paddress (target_gdbarch (),
 776                                       TYPE_LENGTH (regs_type)),
 777                             paddress (target_gdbarch (), regs_addr));
 778       store_regs (regs_type, regs_addr);
 779     }
 780
 781   if (scope == COMPILE_I_PRINT_ADDRESS_SCOPE
 782       || scope == COMPILE_I_PRINT_VALUE_SCOPE)
 783     {
 784       out_value_type = get_out_value_type (func_sym, objfile, scope);
 785       if (out_value_type == NULL)
 786         return NULL;
 787       check_typedef (out_value_type);
 788       out_value_addr = gdbarch_infcall_mmap (target_gdbarch (),
 789                                              TYPE_LENGTH (out_value_type),
 790                                              (GDB_MMAP_PROT_READ
 791                                               | GDB_MMAP_PROT_WRITE));
 792       gdb_assert (out_value_addr != 0);
 793       setup_sections_data.munmap_list.add (out_value_addr,
 794                                            TYPE_LENGTH (out_value_type));
 795       if (compile_debug)
 796         fprintf_unfiltered (gdb_stdlog,
 797                             "allocated %s bytes at %s for printed value\n",
 798                             paddress (target_gdbarch (),
 799                                       TYPE_LENGTH (out_value_type)),
 800                             paddress (target_gdbarch (), out_value_addr));
 801     }
 802
 803   compile_module_up retval (new struct compile_module);
 804   retval->objfile = objfile_holder.release ();
 805   retval->source_file = file_names.source_file ();
 806   retval->func_sym = func_sym;
 807   retval->regs_addr = regs_addr;
 808   retval->scope = scope;
 809   retval->scope_data = scope_data;
 810   retval->out_value_type = out_value_type;
 811   retval->out_value_addr = out_value_addr;
 812   retval->munmap_list = std::move (setup_sections_data.munmap_list);
 813
 814   return retval;
 815 }