gdb/dwarf2/abbrev-cache.c

   1 /* DWARF 2 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 #include "defs.h"
  21 #include "dwarf2/read.h"
  22 #include "dwarf2/abbrev-cache.h"
  23
  24 /* Hash function for an abbrev table.  */
  25
  26 hashval_t
  27 abbrev_cache::hash_table (const void *item)
  28 {
  29   const struct abbrev_table *table = (const struct abbrev_table *) item;
  30   return to_underlying (table->sect_off);
  31 }
  32
  33 /* Comparison function for abbrev table.  */
  34
  35 int
  36 abbrev_cache::eq_table (const void *lhs, const void *rhs)
  37 {
  38   const struct abbrev_table *l_table = (const struct abbrev_table *) lhs;
  39   const search_key *key = (const search_key *) rhs;
  40   return (l_table->section == key->section
  41           && l_table->sect_off == key->offset);
  42 }
  43
  44 abbrev_cache::abbrev_cache ()
  45   : m_tables (htab_create_alloc (20, hash_table, eq_table,
  46                                  htab_delete_entry<abbrev_table>,
  47                                  xcalloc, xfree))
  48 {
  49 }
  50
  51 void
  52 abbrev_cache::add (abbrev_table_up table)
  53 {
  54   /* We allow this as a convenience to the caller.  */
  55   if (table == nullptr)
  56     return;
  57
  58   search_key key = { table->section, table->sect_off };
  59   void **slot = htab_find_slot_with_hash (m_tables.get (), &key,
  60                                           to_underlying (table->sect_off),
  61                                           INSERT);
  62   /* If this one already existed, then it should have been reused.  */
  63   gdb_assert (*slot == nullptr);
  64   *slot = (void *) table.release ();
  65 }