src/share/vm/code/oopRecorder.cpp

Thu, 24 May 2018 18:41:44 +0800

author
aoqi
date
Thu, 24 May 2018 18:41:44 +0800
changeset 8856
ac27a9c85bea
parent 6876
710a3c8b516e
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1998, 2012, 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  */
    25 #include "precompiled.hpp"
    26 #include "ci/ciEnv.hpp"
    27 #include "ci/ciInstance.hpp"
    28 #include "ci/ciMetadata.hpp"
    29 #include "code/oopRecorder.hpp"
    30 #include "memory/allocation.inline.hpp"
    31 #include "oops/oop.inline.hpp"
    33 #ifdef ASSERT
    34 template <class T> int ValueRecorder<T>::_find_index_calls = 0;
    35 template <class T> int ValueRecorder<T>::_hit_indexes      = 0;
    36 template <class T> int ValueRecorder<T>::_missed_indexes   = 0;
    37 #endif //ASSERT
    40 template <class T> ValueRecorder<T>::ValueRecorder(Arena* arena) {
    41   _handles  = NULL;
    42   _indexes  = NULL;
    43   _arena    = arena;
    44   _complete = false;
    45 }
    47 template <class T> template <class X>  ValueRecorder<T>::IndexCache<X>::IndexCache() {
    48   assert(first_index > 0, "initial zero state of cache must be invalid index");
    49   Copy::zero_to_bytes(&_cache[0], sizeof(_cache));
    50 }
    52 template <class T> int ValueRecorder<T>::size() {
    53   _complete = true;
    54   if (_handles == NULL)  return 0;
    55   return _handles->length() * sizeof(T);
    56 }
    58 template <class T> void ValueRecorder<T>::copy_values_to(nmethod* nm) {
    59   assert(_complete, "must be frozen");
    60   maybe_initialize();  // get non-null handles, even if we have no oops
    61   nm->copy_values(_handles);
    62 }
    64 template <class T> void ValueRecorder<T>::maybe_initialize() {
    65   if (_handles == NULL) {
    66     if (_arena != NULL) {
    67       _handles  = new(_arena) GrowableArray<T>(_arena, 10, 0, 0);
    68       _no_finds = new(_arena) GrowableArray<int>(    _arena, 10, 0, 0);
    69     } else {
    70       _handles  = new GrowableArray<T>(10, 0, 0);
    71       _no_finds = new GrowableArray<int>(    10, 0, 0);
    72     }
    73   }
    74 }
    77 template <class T> T ValueRecorder<T>::at(int index) {
    78   // there is always a NULL virtually present as first object
    79   if (index == null_index)  return NULL;
    80   return _handles->at(index - first_index);
    81 }
    84 template <class T> int ValueRecorder<T>::add_handle(T h, bool make_findable) {
    85   assert(!_complete, "cannot allocate more elements after size query");
    86   maybe_initialize();
    87   // indexing uses 1 as an origin--0 means null
    88   int index = _handles->length() + first_index;
    89   _handles->append(h);
    91   // Support correct operation of find_index().
    92   assert(!(make_findable && !is_real(h)), "nulls are not findable");
    93   if (make_findable) {
    94     // This index may be returned from find_index().
    95     if (_indexes != NULL) {
    96       int* cloc = _indexes->cache_location(h);
    97       _indexes->set_cache_location_index(cloc, index);
    98     } else if (index == index_cache_threshold && _arena != NULL) {
    99       _indexes = new(_arena) IndexCache<T>();
   100       for (int i = 0; i < _handles->length(); i++) {
   101         // Load the cache with pre-existing elements.
   102         int index0 = i + first_index;
   103         if (_no_finds->contains(index0))  continue;
   104         int* cloc = _indexes->cache_location(_handles->at(i));
   105         _indexes->set_cache_location_index(cloc, index0);
   106       }
   107     }
   108   } else if (is_real(h)) {
   109     // Remember that this index is not to be returned from find_index().
   110     // This case is rare, because most or all uses of allocate_index pass
   111     // an argument of NULL or Universe::non_oop_word.
   112     // Thus, the expected length of _no_finds is zero.
   113     _no_finds->append(index);
   114   }
   116   return index;
   117 }
   120 template <class T> int ValueRecorder<T>::maybe_find_index(T h) {
   121   debug_only(_find_index_calls++);
   122   assert(!_complete, "cannot allocate more elements after size query");
   123   maybe_initialize();
   124   if (h == NULL)  return null_index;
   125   assert(is_real(h), "must be valid");
   126   int* cloc = (_indexes == NULL)? NULL: _indexes->cache_location(h);
   127   if (cloc != NULL) {
   128     int cindex = _indexes->cache_location_index(cloc);
   129     if (cindex == 0) {
   130       return -1;   // We know this handle is completely new.
   131     }
   132     if (cindex >= first_index && _handles->at(cindex - first_index) == h) {
   133       debug_only(_hit_indexes++);
   134       return cindex;
   135     }
   136     if (!_indexes->cache_location_collision(cloc)) {
   137       return -1;   // We know the current cache occupant is unique to that cloc.
   138     }
   139   }
   141   // Not found in cache, due to a cache collision.  (Or, no cache at all.)
   142   // Do a linear search, most recent to oldest.
   143   for (int i = _handles->length() - 1; i >= 0; i--) {
   144     if (_handles->at(i) == h) {
   145       int findex = i + first_index;
   146       if (_no_finds->contains(findex))  continue;  // oops; skip this one
   147       if (cloc != NULL) {
   148         _indexes->set_cache_location_index(cloc, findex);
   149       }
   150       debug_only(_missed_indexes++);
   151       return findex;
   152     }
   153   }
   154   return -1;
   155 }
   157 // Explicitly instantiate these types
   158 template class ValueRecorder<Metadata*>;
   159 template class ValueRecorder<jobject>;

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