1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/utilities/hashtable.inline.hpp Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,126 @@
1.4 +/*
1.5 + * Copyright 2003 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +// Inline function definitions for hashtable.hpp.
1.29 +
1.30 +
1.31 +// --------------------------------------------------------------------------
1.32 +// Hash function
1.33 +
1.34 +// We originally used hashpjw, but hash P(31) gives just as good results
1.35 +// and is slighly faster. We would like a hash function that looks at every
1.36 +// character, since package names have large common prefixes, and also because
1.37 +// hash_or_fail does error checking while iterating.
1.38 +
1.39 +// hash P(31) from Kernighan & Ritchie
1.40 +
1.41 +inline unsigned int Hashtable::hash_symbol(const char* s, int len) {
1.42 + unsigned int h = 0;
1.43 + while (len-- > 0) {
1.44 + h = 31*h + (unsigned) *s;
1.45 + s++;
1.46 + }
1.47 + return h;
1.48 +}
1.49 +
1.50 +
1.51 +// --------------------------------------------------------------------------
1.52 +
1.53 +// Initialize a table.
1.54 +
1.55 +inline BasicHashtable::BasicHashtable(int table_size, int entry_size) {
1.56 + // Called on startup, no locking needed
1.57 + initialize(table_size, entry_size, 0);
1.58 + _buckets = NEW_C_HEAP_ARRAY(HashtableBucket, table_size);
1.59 + for (int index = 0; index < _table_size; index++) {
1.60 + _buckets[index].clear();
1.61 + }
1.62 +}
1.63 +
1.64 +
1.65 +inline BasicHashtable::BasicHashtable(int table_size, int entry_size,
1.66 + HashtableBucket* buckets,
1.67 + int number_of_entries) {
1.68 + // Called on startup, no locking needed
1.69 + initialize(table_size, entry_size, number_of_entries);
1.70 + _buckets = buckets;
1.71 +}
1.72 +
1.73 +
1.74 +inline void BasicHashtable::initialize(int table_size, int entry_size,
1.75 + int number_of_entries) {
1.76 + // Called on startup, no locking needed
1.77 + _table_size = table_size;
1.78 + _entry_size = entry_size;
1.79 + _free_list = NULL;
1.80 + _first_free_entry = NULL;
1.81 + _end_block = NULL;
1.82 + _number_of_entries = number_of_entries;
1.83 +#ifdef ASSERT
1.84 + _lookup_count = 0;
1.85 + _lookup_length = 0;
1.86 +#endif
1.87 +}
1.88 +
1.89 +
1.90 +// The following method is MT-safe and may be used with caution.
1.91 +inline BasicHashtableEntry* BasicHashtable::bucket(int i) {
1.92 + return _buckets[i].get_entry();
1.93 +}
1.94 +
1.95 +
1.96 +inline void HashtableBucket::set_entry(BasicHashtableEntry* l) {
1.97 + // Warning: Preserve store ordering. The SystemDictionary is read
1.98 + // without locks. The new SystemDictionaryEntry must be
1.99 + // complete before other threads can be allowed to see it
1.100 + // via a store to _buckets[index].
1.101 + OrderAccess::release_store_ptr(&_entry, l);
1.102 +}
1.103 +
1.104 +
1.105 +inline BasicHashtableEntry* HashtableBucket::get_entry() const {
1.106 + // Warning: Preserve load ordering. The SystemDictionary is read
1.107 + // without locks. The new SystemDictionaryEntry must be
1.108 + // complete before other threads can be allowed to see it
1.109 + // via a store to _buckets[index].
1.110 + return (BasicHashtableEntry*) OrderAccess::load_ptr_acquire(&_entry);
1.111 +}
1.112 +
1.113 +
1.114 +inline void BasicHashtable::set_entry(int index, BasicHashtableEntry* entry) {
1.115 + _buckets[index].set_entry(entry);
1.116 +}
1.117 +
1.118 +
1.119 +inline void BasicHashtable::add_entry(int index, BasicHashtableEntry* entry) {
1.120 + entry->set_next(bucket(index));
1.121 + _buckets[index].set_entry(entry);
1.122 + ++_number_of_entries;
1.123 +}
1.124 +
1.125 +inline void BasicHashtable::free_entry(BasicHashtableEntry* entry) {
1.126 + entry->set_next(_free_list);
1.127 + _free_list = entry;
1.128 + --_number_of_entries;
1.129 +}
