gdb/dwarf2/cu.c

   1 /* DWARF CU data structure
   2
   3    Copyright (C) 2021-2022 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 "dwarf2/cu.h"
  22 #include "dwarf2/read.h"
  23 #include "objfiles.h"
  24 #include "filenames.h"
  25 #include "gdbsupport/pathstuff.h"
  26
  27 /* Initialize dwarf2_cu to read PER_CU, in the context of PER_OBJFILE.  */
  28
  29 dwarf2_cu::dwarf2_cu (dwarf2_per_cu_data *per_cu,
  30                       dwarf2_per_objfile *per_objfile)
  31   : per_cu (per_cu),
  32     per_objfile (per_objfile),
  33     m_mark (false),
  34     has_loclist (false),
  35     checked_producer (false),
  36     producer_is_gxx_lt_4_6 (false),
  37     producer_is_gcc_lt_4_3 (false),
  38     producer_is_gcc_11 (false),
  39     producer_is_icc (false),
  40     producer_is_icc_lt_14 (false),
  41     producer_is_codewarrior (false),
  42     processing_has_namespace_info (false),
  43     load_all_dies (false)
  44 {
  45 }
  46
  47 /* See cu.h.  */
  48
  49 struct type *
  50 dwarf2_cu::addr_sized_int_type (bool unsigned_p) const
  51 {
  52   int addr_size = this->per_cu->addr_size ();
  53   return objfile_int_type (this->per_objfile->objfile, addr_size, unsigned_p);
  54 }
  55
  56 /* Start a symtab for DWARF.  NAME, COMP_DIR, LOW_PC are passed to the
  57    buildsym_compunit constructor.  */
  58
  59 struct compunit_symtab *
  60 dwarf2_cu::start_compunit_symtab (const char *name, const char *comp_dir,
  61                                   CORE_ADDR low_pc)
  62 {
  63   gdb_assert (m_builder == nullptr);
  64
  65   std::string name_for_id_holder;
  66   const char *name_for_id = name;
  67
  68   /* Prepend the compilation directory to the filename if needed (if not
  69      absolute already) to get the "name for id" for our main symtab.  The name
  70      for the main file coming from the line table header will be generated using
  71      the same logic, so will hopefully match what we pass here.  */
  72   if (!IS_ABSOLUTE_PATH (name) && comp_dir != nullptr)
  73     {
  74       name_for_id_holder = path_join (comp_dir, name);
  75       name_for_id = name_for_id_holder.c_str ();
  76     }
  77
  78   m_builder.reset (new struct buildsym_compunit
  79                    (this->per_objfile->objfile,
  80                     name, comp_dir, name_for_id, lang (), low_pc));
  81
  82   list_in_scope = get_builder ()->get_file_symbols ();
  83
  84   /* DWARF versions are restricted to [2, 5], thanks to the check in
  85      read_comp_unit_head.  */
  86   gdb_assert (this->header.version >= 2 && this->header.version <= 5);
  87   static const char *debugformat_strings[] = {
  88     "DWARF 2",
  89     "DWARF 3",
  90     "DWARF 4",
  91     "DWARF 5",
  92   };
  93   const char *debugformat = debugformat_strings[this->header.version - 2];
  94
  95   get_builder ()->record_debugformat (debugformat);
  96   get_builder ()->record_producer (producer);
  97
  98   processing_has_namespace_info = false;
  99
 100   return get_builder ()->get_compunit_symtab ();
 101 }
 102
 103 /* See read.h.  */
 104
 105 struct type *
 106 dwarf2_cu::addr_type () const
 107 {
 108   struct objfile *objfile = this->per_objfile->objfile;
 109   struct type *void_type = objfile_type (objfile)->builtin_void;
 110   struct type *addr_type = lookup_pointer_type (void_type);
 111   int addr_size = this->per_cu->addr_size ();
 112
 113   if (TYPE_LENGTH (addr_type) == addr_size)
 114     return addr_type;
 115
 116   addr_type = addr_sized_int_type (addr_type->is_unsigned ());
 117   return addr_type;
 118 }
 119
 120 /* A hashtab traversal function that marks the dependent CUs.  */
 121
 122 static int
 123 dwarf2_mark_helper (void **slot, void *data)
 124 {
 125   dwarf2_per_cu_data *per_cu = (dwarf2_per_cu_data *) *slot;
 126   dwarf2_per_objfile *per_objfile = (dwarf2_per_objfile *) data;
 127   dwarf2_cu *cu = per_objfile->get_cu (per_cu);
 128
 129   /* cu->m_dependencies references may not yet have been ever read if
 130      QUIT aborts reading of the chain.  As such dependencies remain
 131      valid it is not much useful to track and undo them during QUIT
 132      cleanups.  */
 133   if (cu != nullptr)
 134     cu->mark ();
 135   return 1;
 136 }
 137
 138 /* See dwarf2/cu.h.  */
 139
 140 void
 141 dwarf2_cu::mark ()
 142 {
 143   if (!m_mark)
 144     {
 145       m_mark = true;
 146       if (m_dependencies != nullptr)
 147         htab_traverse (m_dependencies, dwarf2_mark_helper, per_objfile);
 148     }
 149 }
 150
 151 /* See dwarf2/cu.h.  */
 152
 153 void
 154 dwarf2_cu::add_dependence (struct dwarf2_per_cu_data *ref_per_cu)
 155 {
 156   void **slot;
 157
 158   if (m_dependencies == nullptr)
 159     m_dependencies
 160       = htab_create_alloc_ex (5, htab_hash_pointer, htab_eq_pointer,
 161                               NULL, &comp_unit_obstack,
 162                               hashtab_obstack_allocate,
 163                               dummy_obstack_deallocate);
 164
 165   slot = htab_find_slot (m_dependencies, ref_per_cu, INSERT);
 166   if (*slot == nullptr)
 167     *slot = ref_per_cu;
 168 }
 169
 170 /* See dwarf2/cu.h.  */
 171
 172 buildsym_compunit *
 173 dwarf2_cu::get_builder ()
 174 {
 175   /* If this CU has a builder associated with it, use that.  */
 176   if (m_builder != nullptr)
 177     return m_builder.get ();
 178
 179   if (per_objfile->sym_cu != nullptr)
 180     return per_objfile->sym_cu->m_builder.get ();
 181
 182   gdb_assert_not_reached ("");
 183 }