duke@435: /*
jrose@1934:  * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: # include "incls/_precompiled.incl"
duke@435: # include "incls/_oopRecorder.cpp.incl"
duke@435: 
duke@435: #ifdef ASSERT
duke@435: int OopRecorder::_find_index_calls = 0;
duke@435: int OopRecorder::_hit_indexes      = 0;
duke@435: int OopRecorder::_missed_indexes   = 0;
duke@435: #endif //ASSERT
duke@435: 
duke@435: 
duke@435: OopRecorder::OopRecorder(Arena* arena) {
duke@435:   _handles  = NULL;
duke@435:   _indexes  = NULL;
duke@435:   _arena    = arena;
duke@435:   _complete = false;
duke@435: }
duke@435: 
duke@435: OopRecorder::IndexCache::IndexCache() {
duke@435:   assert(first_index > 0, "initial zero state of cache must be invalid index");
duke@435:   Copy::zero_to_bytes(&_cache[0], sizeof(_cache));
duke@435: }
duke@435: 
duke@435: int OopRecorder::oop_size() {
duke@435:   _complete = true;
duke@435:   if (_handles == NULL)  return 0;
duke@435:   return _handles->length() * sizeof(oop);
duke@435: }
duke@435: 
twisti@1918: void OopRecorder::copy_to(nmethod* nm) {
duke@435:   assert(_complete, "must be frozen");
duke@435:   maybe_initialize();  // get non-null handles, even if we have no oops
twisti@1918:   nm->copy_oops(_handles);
duke@435: }
duke@435: 
duke@435: void OopRecorder::maybe_initialize() {
duke@435:   if (_handles == NULL) {
duke@435:     if (_arena != NULL) {
duke@435:       _handles  = new(_arena) GrowableArray<jobject>(_arena, 10, 0, 0);
duke@435:       _no_finds = new(_arena) GrowableArray<int>(    _arena, 10, 0, 0);
duke@435:     } else {
duke@435:       _handles  = new GrowableArray<jobject>(10, 0, 0);
duke@435:       _no_finds = new GrowableArray<int>(    10, 0, 0);
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: jobject OopRecorder::handle_at(int index) {
duke@435:   // there is always a NULL virtually present as first object
duke@435:   if (index == null_index)  return NULL;
duke@435:   return _handles->at(index - first_index);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Local definition.  Used only in this module.
duke@435: inline bool OopRecorder::is_real_jobject(jobject h) {
duke@435:   return h != NULL && h != (jobject)Universe::non_oop_word();
duke@435: }
duke@435: 
duke@435: 
duke@435: int OopRecorder::add_handle(jobject h, bool make_findable) {
duke@435:   assert(!_complete, "cannot allocate more elements after size query");
duke@435:   maybe_initialize();
duke@435:   // indexing uses 1 as an origin--0 means null
duke@435:   int index = _handles->length() + first_index;
duke@435:   _handles->append(h);
duke@435: 
duke@435:   // Support correct operation of find_index().
duke@435:   assert(!(make_findable && !is_real_jobject(h)), "nulls are not findable");
duke@435:   if (make_findable) {
duke@435:     // This index may be returned from find_index().
duke@435:     if (_indexes != NULL) {
duke@435:       int* cloc = _indexes->cache_location(h);
duke@435:       _indexes->set_cache_location_index(cloc, index);
duke@435:     } else if (index == index_cache_threshold && _arena != NULL) {
duke@435:       _indexes = new(_arena) IndexCache();
duke@435:       for (int i = 0; i < _handles->length(); i++) {
duke@435:         // Load the cache with pre-existing elements.
duke@435:         int index0 = i + first_index;
duke@435:         if (_no_finds->contains(index0))  continue;
duke@435:         int* cloc = _indexes->cache_location(_handles->at(i));
duke@435:         _indexes->set_cache_location_index(cloc, index0);
duke@435:       }
duke@435:     }
duke@435:   } else if (is_real_jobject(h)) {
duke@435:     // Remember that this index is not to be returned from find_index().
duke@435:     // This case is rare, because most or all uses of allocate_index pass
duke@435:     // a jobject argument of NULL or Universe::non_oop_word.
duke@435:     // Thus, the expected length of _no_finds is zero.
duke@435:     _no_finds->append(index);
duke@435:   }
duke@435: 
duke@435:   return index;
duke@435: }
duke@435: 
duke@435: 
duke@435: int OopRecorder::maybe_find_index(jobject h) {
duke@435:   debug_only(_find_index_calls++);
duke@435:   assert(!_complete, "cannot allocate more elements after size query");
duke@435:   maybe_initialize();
duke@435:   if (h == NULL)  return null_index;
duke@435:   assert(is_real_jobject(h), "must be valid jobject");
duke@435:   int* cloc = (_indexes == NULL)? NULL: _indexes->cache_location(h);
duke@435:   if (cloc != NULL) {
duke@435:     int cindex = _indexes->cache_location_index(cloc);
duke@435:     if (cindex == 0) {
duke@435:       return -1;   // We know this handle is completely new.
duke@435:     }
duke@435:     if (cindex >= first_index && _handles->at(cindex - first_index) == h) {
duke@435:       debug_only(_hit_indexes++);
duke@435:       return cindex;
duke@435:     }
duke@435:     if (!_indexes->cache_location_collision(cloc)) {
duke@435:       return -1;   // We know the current cache occupant is unique to that cloc.
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // Not found in cache, due to a cache collision.  (Or, no cache at all.)
duke@435:   // Do a linear search, most recent to oldest.
duke@435:   for (int i = _handles->length() - 1; i >= 0; i--) {
duke@435:     if (_handles->at(i) == h) {
duke@435:       int findex = i + first_index;
duke@435:       if (_no_finds->contains(findex))  continue;  // oops; skip this one
duke@435:       if (cloc != NULL) {
duke@435:         _indexes->set_cache_location_index(cloc, findex);
duke@435:       }
duke@435:       debug_only(_missed_indexes++);
duke@435:       return findex;
duke@435:     }
duke@435:   }
duke@435:   return -1;
duke@435: }