gdb/dwarf2/abbrev-cache.h

   1 /* DWARF abbrev table cache
   2
   3    Copyright (C) 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 #ifndef GDB_DWARF2_ABBREV_CACHE_H
  21 #define GDB_DWARF2_ABBREV_CACHE_H
  22
  23 #include "dwarf2/abbrev.h"
  24 #include "gdbtypes.h"
  25
  26 /* An abbrev cache holds abbrev tables for easier reuse.  */
  27 class abbrev_cache
  28 {
  29 public:
  30   abbrev_cache ();
  31   DISABLE_COPY_AND_ASSIGN (abbrev_cache);
  32
  33   /* Find an abbrev table coming from the abbrev section SECTION at
  34      offset OFFSET.  Return the table, or nullptr if it has not yet
  35      been registered.  */
  36   abbrev_table *find (struct dwarf2_section_info *section, sect_offset offset)
  37   {
  38     search_key key = { section, offset };
  39
  40     return (abbrev_table *) htab_find_with_hash (m_tables.get (), &key,
  41                                                  to_underlying (offset));
  42   }
  43
  44   /* Add TABLE to this cache.  Ownership of TABLE is transferred to
  45      the cache.  Note that a table at a given section+offset may only
  46      be registered once -- a violation of this will cause an assert.
  47      To avoid this, call the 'find' method first, to see if the table
  48      has already been read.  */
  49   void add (abbrev_table_up table);
  50
  51 private:
  52
  53   static hashval_t hash_table (const void *item);
  54   static int eq_table (const void *lhs, const void *rhs);
  55
  56   struct search_key
  57   {
  58     struct dwarf2_section_info *section;
  59     sect_offset offset;
  60   };
  61
  62   /* Hash table of abbrev tables.  */
  63   htab_up m_tables;
  64 };
  65
  66 #endif /* GDB_DWARF2_ABBREV_CACHE_H */