1 /*
   2  * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_resolutionErrors.cpp.incl"
  27 
  28 // add new entry to the table
  29 void ResolutionErrorTable::add_entry(int index, unsigned int hash,
  30                                      constantPoolHandle pool, int cp_index, symbolHandle error)
  31 {
  32   assert_locked_or_safepoint(SystemDictionary_lock);
  33   assert(!pool.is_null() && !error.is_null(), "adding NULL obj");
  34 
  35   ResolutionErrorEntry* entry = new_entry(hash, pool(), cp_index, error());
  36   add_entry(index, entry);
  37 }
  38 
  39 // find entry in the table
  40 ResolutionErrorEntry* ResolutionErrorTable::find_entry(int index, unsigned int hash,
  41                                                        constantPoolHandle pool, int cp_index)
  42 {
  43   assert_locked_or_safepoint(SystemDictionary_lock);
  44 
  45   for (ResolutionErrorEntry *error_probe = bucket(index);
  46                          error_probe != NULL;
  47                          error_probe = error_probe->next()) {
  48   if (error_probe->hash() == hash && error_probe->pool() == pool()) {
  49       return error_probe;;
  50     }
  51   }
  52   return NULL;
  53 }
  54 
  55 // create new error entry
  56 ResolutionErrorEntry* ResolutionErrorTable::new_entry(int hash, constantPoolOop pool,
  57                                                       int cp_index, symbolOop error)
  58 {
  59   ResolutionErrorEntry* entry = (ResolutionErrorEntry*)Hashtable::new_entry(hash, pool);
  60   entry->set_cp_index(cp_index);
  61   entry->set_error(error);
  62 
  63   return entry;
  64 }
  65 
  66 // create resolution error table
  67 ResolutionErrorTable::ResolutionErrorTable(int table_size)
  68     : Hashtable(table_size, sizeof(ResolutionErrorEntry)) {
  69 }
  70 
  71 // GC support
  72 void ResolutionErrorTable::oops_do(OopClosure* f) {
  73   for (int i = 0; i < table_size(); i++) {
  74     for (ResolutionErrorEntry* probe = bucket(i);
  75                            probe != NULL;
  76                            probe = probe->next()) {
  77       assert(probe->pool() != (constantPoolOop)NULL, "resolution error table is corrupt");
  78       assert(probe->error() != (symbolOop)NULL, "resolution error table is corrupt");
  79       probe->oops_do(f);
  80     }
  81   }
  82 }
  83 
  84 // GC support
  85 void ResolutionErrorEntry::oops_do(OopClosure* blk) {
  86   blk->do_oop((oop*)pool_addr());
  87   blk->do_oop((oop*)error_addr());
  88 }
  89 
  90 // We must keep the symbolOop used in the error alive. The constantPoolOop will
  91 // decide when the entry can be purged.
  92 void ResolutionErrorTable::always_strong_classes_do(OopClosure* blk) {
  93   for (int i = 0; i < table_size(); i++) {
  94     for (ResolutionErrorEntry* probe = bucket(i);
  95                            probe != NULL;
  96                            probe = probe->next()) {
  97       assert(probe->error() != (symbolOop)NULL, "resolution error table is corrupt");
  98       blk->do_oop((oop*)probe->error_addr());
  99     }
 100   }
 101 }
 102 
 103 // Remove unloaded entries from the table
 104 void ResolutionErrorTable::purge_resolution_errors(BoolObjectClosure* is_alive) {
 105   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 106   for (int i = 0; i < table_size(); i++) {
 107     for (ResolutionErrorEntry** p = bucket_addr(i); *p != NULL; ) {
 108       ResolutionErrorEntry* entry = *p;
 109       assert(entry->pool() != (constantPoolOop)NULL, "resolution error table is corrupt");
 110       constantPoolOop pool = entry->pool();
 111       if (is_alive->do_object_b(pool)) {
 112         p = entry->next_addr();
 113       } else {
 114         *p = entry->next();
 115         free_entry(entry);
 116       }
 117     }
 118   }
 119 }