1 /*
  2  * Copyright (c) 2018, 2025, 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 #ifndef SHARE_CDS_HEAPSHARED_HPP
 26 #define SHARE_CDS_HEAPSHARED_HPP
 27 
 28 #include "cds/aotMetaspace.hpp"
 29 #include "cds/cds_globals.hpp"
 30 #include "cds/dumpTimeClassInfo.hpp"
 31 #include "classfile/compactHashtable.hpp"
 32 #include "classfile/javaClasses.hpp"
 33 #include "gc/shared/gc_globals.hpp"
 34 #include "memory/allocation.hpp"
 35 #include "memory/allStatic.hpp"
 36 #include "oops/compressedOops.hpp"
 37 #include "oops/oop.hpp"
 38 #include "oops/oopHandle.hpp"
 39 #include "oops/oopsHierarchy.hpp"
 40 #include "utilities/growableArray.hpp"
 41 #include "utilities/hashTable.hpp"
 42 
 43 #if INCLUDE_CDS_JAVA_HEAP
 44 class DumpedInternedStrings;
 45 class FileMapInfo;
 46 class KlassSubGraphInfo;
 47 class MetaspaceObjToOopHandleTable;
 48 class ResourceBitMap;
 49 
 50 struct ArchivableStaticFieldInfo;
 51 
 52 #define ARCHIVED_BOOT_LAYER_CLASS "jdk/internal/module/ArchivedBootLayer"
 53 #define ARCHIVED_BOOT_LAYER_FIELD "archivedBootLayer"
 54 
 55 // A dump time sub-graph info for Klass _k. It includes the entry points
 56 // (static fields in _k's mirror) of the archived sub-graphs reachable
 57 // from _k's mirror. It also contains a list of Klasses of the objects
 58 // within the sub-graphs.
 59 class KlassSubGraphInfo: public CHeapObj<mtClass> {
 60  private:
 61   // The class that contains the static field(s) as the entry point(s)
 62   // of archived object sub-graph(s).
 63   Klass* _k;
 64   // A list of classes need to be loaded and initialized before the archived
 65   // object sub-graphs can be accessed at runtime.
 66   GrowableArray<Klass*>* _subgraph_object_klasses;
 67   // A list of _k's static fields as the entry points of archived sub-graphs.
 68   // For each entry field, it is a tuple of field_offset, field_value
 69   GrowableArray<int>* _subgraph_entry_fields;
 70 
 71   // Does this KlassSubGraphInfo belong to the archived full module graph
 72   bool _is_full_module_graph;
 73 
 74   // Does this KlassSubGraphInfo references any classes that were loaded while
 75   // JvmtiExport::is_early_phase()!=true. If so, this KlassSubGraphInfo cannot be
 76   // used at runtime if JVMTI ClassFileLoadHook is enabled.
 77   bool _has_non_early_klasses;
 78   static bool is_non_early_klass(Klass* k);
 79   static void check_allowed_klass(InstanceKlass* ik);
 80  public:
 81   KlassSubGraphInfo(Klass* k, bool is_full_module_graph) :
 82     _k(k),  _subgraph_object_klasses(nullptr),
 83     _subgraph_entry_fields(nullptr),
 84     _is_full_module_graph(is_full_module_graph),
 85     _has_non_early_klasses(false) {}
 86 
 87   ~KlassSubGraphInfo() {
 88     if (_subgraph_object_klasses != nullptr) {
 89       delete _subgraph_object_klasses;
 90     }
 91     if (_subgraph_entry_fields != nullptr) {
 92       delete _subgraph_entry_fields;
 93     }
 94   };
 95 
 96   Klass* klass()            { return _k; }
 97   GrowableArray<Klass*>* subgraph_object_klasses() {
 98     return _subgraph_object_klasses;
 99   }
100   GrowableArray<int>* subgraph_entry_fields() {
101     return _subgraph_entry_fields;
102   }
103   void add_subgraph_entry_field(int static_field_offset, oop v);
104   void add_subgraph_object_klass(Klass *orig_k);
105   int num_subgraph_object_klasses() {
106     return _subgraph_object_klasses == nullptr ? 0 :
107            _subgraph_object_klasses->length();
108   }
109   bool is_full_module_graph() const { return _is_full_module_graph; }
110   bool has_non_early_klasses() const { return _has_non_early_klasses; }
111 };
112 
113 // An archived record of object sub-graphs reachable from static
114 // fields within _k's mirror. The record is reloaded from the archive
115 // at runtime.
116 class ArchivedKlassSubGraphInfoRecord {
117  private:
118   Klass* _k;
119   bool _is_full_module_graph;
120   bool _has_non_early_klasses;
121 
122   // contains pairs of field offset and value for each subgraph entry field
123   Array<int>* _entry_field_records;
124 
125   // klasses of objects in archived sub-graphs referenced from the entry points
126   // (static fields) in the containing class
127   Array<Klass*>* _subgraph_object_klasses;
128  public:
129   ArchivedKlassSubGraphInfoRecord() :
130     _k(nullptr), _entry_field_records(nullptr), _subgraph_object_klasses(nullptr) {}
131   void init(KlassSubGraphInfo* info);
132   Klass* klass() const { return _k; }
133   Array<int>* entry_field_records() const { return _entry_field_records; }
134   Array<Klass*>* subgraph_object_klasses() const { return _subgraph_object_klasses; }
135   bool is_full_module_graph() const { return _is_full_module_graph; }
136   bool has_non_early_klasses() const { return _has_non_early_klasses; }
137 };
138 #endif // INCLUDE_CDS_JAVA_HEAP
139 
140 enum class HeapArchiveMode {
141   _uninitialized,
142   _mapping,
143   _streaming
144 };
145 
146 class ArchiveMappedHeapHeader {
147   size_t           _ptrmap_start_pos; // The first bit in the ptrmap corresponds to this position in the heap.
148   size_t           _oopmap_start_pos; // The first bit in the oopmap corresponds to this position in the heap.
149   HeapRootSegments _root_segments;    // Heap root segments info
150 
151 public:
152   ArchiveMappedHeapHeader();
153   ArchiveMappedHeapHeader(size_t ptrmap_start_pos,
154                           size_t oopmap_start_pos,
155                           HeapRootSegments root_segments);
156 
157   size_t ptrmap_start_pos() const { return _ptrmap_start_pos; }
158   size_t oopmap_start_pos() const { return _oopmap_start_pos; }
159   HeapRootSegments root_segments() const { return _root_segments; }
160 
161   // This class is trivially copyable and assignable.
162   ArchiveMappedHeapHeader(const ArchiveMappedHeapHeader&) = default;
163   ArchiveMappedHeapHeader& operator=(const ArchiveMappedHeapHeader&) = default;
164 };
165 
166 
167 class ArchiveStreamedHeapHeader {
168   size_t _forwarding_offset;                      // Offset of forwarding information in the heap region.
169   size_t _roots_offset;                           // Start position for the roots
170   size_t _root_highest_object_index_table_offset; // Offset of root dfs depth information
171   size_t _num_roots;                              // Number of embedded roots
172   size_t _num_archived_objects;                   // The number of archived heap objects
173 
174 public:
175   ArchiveStreamedHeapHeader();
176   ArchiveStreamedHeapHeader(size_t forwarding_offset,
177                             size_t roots_offset,
178                             size_t num_roots,
179                             size_t root_highest_object_index_table_offset,
180                             size_t num_archived_objects);
181 
182   size_t forwarding_offset() const { return _forwarding_offset; }
183   size_t roots_offset() const { return _roots_offset; }
184   size_t num_roots() const { return _num_roots; }
185   size_t root_highest_object_index_table_offset() const { return _root_highest_object_index_table_offset; }
186   size_t num_archived_objects() const { return _num_archived_objects; }
187 
188   // This class is trivially copyable and assignable.
189   ArchiveStreamedHeapHeader(const ArchiveStreamedHeapHeader&) = default;
190   ArchiveStreamedHeapHeader& operator=(const ArchiveStreamedHeapHeader&) = default;
191 };
192 
193 class ArchiveMappedHeapInfo {
194   MemRegion _buffer_region;             // Contains the archived objects to be written into the CDS archive.
195   CHeapBitMap _oopmap;
196   CHeapBitMap _ptrmap;
197   HeapRootSegments _root_segments;
198   size_t _oopmap_start_pos;             // How many zeros were removed from the beginning of the bit map?
199   size_t _ptrmap_start_pos;             // How many zeros were removed from the beginning of the bit map?
200 
201 public:
202   ArchiveMappedHeapInfo() :
203     _buffer_region(),
204     _oopmap(128, mtClassShared),
205     _ptrmap(128, mtClassShared),
206     _root_segments(),
207     _oopmap_start_pos(),
208     _ptrmap_start_pos() {}
209   bool is_used() { return !_buffer_region.is_empty(); }
210 
211   MemRegion buffer_region() { return _buffer_region; }
212   void set_buffer_region(MemRegion r) { _buffer_region = r; }
213 
214   char* buffer_start() { return (char*)_buffer_region.start(); }
215   size_t buffer_byte_size() { return _buffer_region.byte_size();    }
216 
217   CHeapBitMap* oopmap() { return &_oopmap; }
218   CHeapBitMap* ptrmap() { return &_ptrmap; }
219 
220   void set_oopmap_start_pos(size_t start_pos) { _oopmap_start_pos = start_pos; }
221   void set_ptrmap_start_pos(size_t start_pos) { _ptrmap_start_pos = start_pos; }
222 
223   void set_root_segments(HeapRootSegments segments) { _root_segments = segments; };
224   HeapRootSegments root_segments() { return _root_segments; }
225 
226   ArchiveMappedHeapHeader create_header();
227 };
228 
229 class ArchiveStreamedHeapInfo {
230   MemRegion _buffer_region;             // Contains the archived objects to be written into the CDS archive.
231   CHeapBitMap _oopmap;
232   size_t _roots_offset;                 // Offset of the HeapShared::roots() object, from the bottom
233                                         // of the archived heap objects, in bytes.
234   size_t _num_roots;
235 
236   size_t _forwarding_offset;            // Offset of forwarding information from the bottom
237   size_t _root_highest_object_index_table_offset; // Offset to root dfs depth information
238   size_t _num_archived_objects;         // The number of archived objects written into the CDS archive.
239 
240 public:
241   ArchiveStreamedHeapInfo()
242     : _buffer_region(),
243       _oopmap(128, mtClassShared),
244       _roots_offset(),
245       _forwarding_offset(),
246       _root_highest_object_index_table_offset(),
247       _num_archived_objects() {}
248 
249   bool is_used() { return !_buffer_region.is_empty(); }
250 
251   void set_buffer_region(MemRegion r) { _buffer_region = r; }
252   MemRegion buffer_region() { return _buffer_region; }
253   char* buffer_start() { return (char*)_buffer_region.start(); }
254   size_t buffer_byte_size() { return _buffer_region.byte_size();    }
255 
256   CHeapBitMap* oopmap() { return &_oopmap; }
257   void set_roots_offset(size_t n) { _roots_offset = n; }
258   size_t roots_offset() { return _roots_offset; }
259   void set_num_roots(size_t n) { _num_roots = n; }
260   size_t num_roots() { return _num_roots; }
261   void set_forwarding_offset(size_t n) { _forwarding_offset = n; }
262   void set_root_highest_object_index_table_offset(size_t n) { _root_highest_object_index_table_offset = n; }
263   void set_num_archived_objects(size_t n) { _num_archived_objects = n; }
264   size_t num_archived_objects() { return _num_archived_objects; }
265 
266   ArchiveStreamedHeapHeader create_header();
267 };
268 
269 class HeapShared: AllStatic {
270   friend class VerifySharedOopClosure;
271 
272 public:
273   static void initialize_loading_mode(HeapArchiveMode mode) NOT_CDS_JAVA_HEAP_RETURN;
274   static void initialize_writing_mode() NOT_CDS_JAVA_HEAP_RETURN;
275 
276   inline static bool is_loading() NOT_CDS_JAVA_HEAP_RETURN_(false);
277 
278   inline static bool is_loading_streaming_mode() NOT_CDS_JAVA_HEAP_RETURN_(false);
279   inline static bool is_loading_mapping_mode() NOT_CDS_JAVA_HEAP_RETURN_(false);
280 
281   inline static bool is_writing() NOT_CDS_JAVA_HEAP_RETURN_(false);
282 
283   inline static bool is_writing_streaming_mode() NOT_CDS_JAVA_HEAP_RETURN_(false);
284   inline static bool is_writing_mapping_mode() NOT_CDS_JAVA_HEAP_RETURN_(false);
285 
286   static bool is_subgraph_root_class(InstanceKlass* ik);
287 
288   // Scratch objects for archiving Klass::java_mirror()
289   static oop scratch_java_mirror(BasicType t)     NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
290   static oop scratch_java_mirror(Klass* k)        NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
291   static oop scratch_java_mirror(oop java_mirror) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
292   static bool is_archived_boot_layer_available(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN_(false);
293 
294   static bool is_archived_heap_in_use() NOT_CDS_JAVA_HEAP_RETURN_(false);
295   static bool can_use_archived_heap() NOT_CDS_JAVA_HEAP_RETURN_(false);
296   static bool is_too_large_to_archive(size_t size);
297   static bool is_string_too_large_to_archive(oop string);
298   static bool is_too_large_to_archive(oop obj);
299 
300   static void initialize_streaming() NOT_CDS_JAVA_HEAP_RETURN;
301   static void enable_gc() NOT_CDS_JAVA_HEAP_RETURN;
302   static void materialize_thread_object() NOT_CDS_JAVA_HEAP_RETURN;
303   static void add_to_dumped_interned_strings(oop string) NOT_CDS_JAVA_HEAP_RETURN;
304   static void finalize_initialization(FileMapInfo* static_mapinfo) NOT_CDS_JAVA_HEAP_RETURN;
305 
306 private:
307 #if INCLUDE_CDS_JAVA_HEAP
308   static HeapArchiveMode _heap_load_mode;
309   static HeapArchiveMode _heap_write_mode;
310 
311   // statistics
312   constexpr static int ALLOC_STAT_SLOTS = 16;
313   static size_t _alloc_count[ALLOC_STAT_SLOTS];
314   static size_t _alloc_size[ALLOC_STAT_SLOTS];
315   static size_t _total_obj_count;
316   static size_t _total_obj_size; // in HeapWords
317 
318   static void count_allocation(size_t size);
319   static void print_stats();
320 public:
321   static void debug_trace();
322   static unsigned oop_hash(oop const& p);
323   static unsigned oop_handle_hash(OopHandle const& oh);
324   static unsigned oop_handle_hash_raw(OopHandle const& oh);
325   static bool oop_handle_equals(const OopHandle& a, const OopHandle& b);
326   static unsigned string_oop_hash(oop const& string) {
327     return java_lang_String::hash_code(string);
328   }
329 
330   class CopyKlassSubGraphInfoToArchive;
331 
332   class CachedOopInfo {
333     // Used by CDSHeapVerifier.
334     OopHandle _orig_referrer;
335 
336     // The location of this object inside ArchiveHeapWriter::_buffer
337     size_t _buffer_offset;
338 
339     // One or more fields in this object are pointing to non-null oops.
340     bool _has_oop_pointers;
341 
342     // One or more fields in this object are pointing to MetaspaceObj
343     bool _has_native_pointers;
344   public:
345     CachedOopInfo(OopHandle orig_referrer, bool has_oop_pointers)
346       : _orig_referrer(orig_referrer),
347         _buffer_offset(0),
348         _has_oop_pointers(has_oop_pointers),
349         _has_native_pointers(false) {}
350     oop orig_referrer() const;
351     void set_buffer_offset(size_t offset) { _buffer_offset = offset; }
352     size_t buffer_offset()          const { return _buffer_offset;   }
353     bool has_oop_pointers()         const { return _has_oop_pointers; }
354     bool has_native_pointers()      const { return _has_native_pointers; }
355     void set_has_native_pointers()        { _has_native_pointers = true; }
356   };
357 
358 private:
359   static const int INITIAL_TABLE_SIZE = 15889; // prime number
360   static const int MAX_TABLE_SIZE     = 1000000;
361   typedef ResizeableHashTable<OopHandle, CachedOopInfo,
362       AnyObj::C_HEAP,
363       mtClassShared,
364       HeapShared::oop_handle_hash_raw,
365       HeapShared::oop_handle_equals> ArchivedObjectCache;
366   static ArchivedObjectCache* _archived_object_cache;
367 
368   class DumpTimeKlassSubGraphInfoTable
369     : public HashTable<Klass*, KlassSubGraphInfo,
370                                137, // prime number
371                                AnyObj::C_HEAP,
372                                mtClassShared,
373                                DumpTimeSharedClassTable_hash> {};
374 
375 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
376   inline static bool record_equals_compact_hashtable_entry(
377        const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
378     return (value->klass() == key);
379   }
380 
381 private:
382   typedef OffsetCompactHashtable<
383     const Klass*,
384     const ArchivedKlassSubGraphInfoRecord*,
385     record_equals_compact_hashtable_entry
386     > RunTimeKlassSubGraphInfoTable;
387 
388   static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
389   static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
390 
391   static CachedOopInfo make_cached_oop_info(oop obj, oop referrer);
392   static ArchivedKlassSubGraphInfoRecord* archive_subgraph_info(KlassSubGraphInfo* info);
393   static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
394                                        bool is_full_module_graph);
395 
396   // Archive object sub-graph starting from the given static field
397   // in Klass k's mirror.
398   static void archive_reachable_objects_from_static_field(
399     InstanceKlass* k, const char* klass_name,
400     int field_offset, const char* field_name);
401 
402   static void verify_subgraph_from_static_field(
403     InstanceKlass* k, int field_offset) PRODUCT_RETURN;
404   static void verify_reachable_objects_from(oop obj) PRODUCT_RETURN;
405   static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
406   static void check_special_subgraph_classes();
407 
408   static KlassSubGraphInfo* init_subgraph_info(Klass *k, bool is_full_module_graph);
409   static KlassSubGraphInfo* get_subgraph_info(Klass *k);
410 
411   static void init_subgraph_entry_fields(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
412   static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[], TRAPS);
413 
414   // UseCompressedOops only: Used by decode_from_archive
415   static address _narrow_oop_base;
416   static int     _narrow_oop_shift;
417 
418   // !UseCompressedOops only: used to relocate pointers to the archived objects
419   static ptrdiff_t _runtime_delta;
420 
421   typedef ResizeableHashTable<oop, bool,
422       AnyObj::C_HEAP,
423       mtClassShared,
424       HeapShared::oop_hash> SeenObjectsTable;
425 
426   static SeenObjectsTable *_seen_objects_table;
427   // The "special subgraph" contains all the archived objects that are reachable
428   // from the following roots:
429   //    - interned strings
430   //    - Klass::java_mirror() -- including aot-initialized mirrors such as those of Enum klasses.
431   //    - ConstantPool::resolved_references()
432   //    - Universe::<xxx>_exception_instance()
433   static KlassSubGraphInfo* _dump_time_special_subgraph;              // for collecting info during dump time
434   static ArchivedKlassSubGraphInfoRecord* _run_time_special_subgraph; // for initializing classes during run time.
435 
436   static GrowableArrayCHeap<OopHandle, mtClassShared>* _pending_roots;
437   static GrowableArrayCHeap<const char*, mtClassShared>* _context; // for debugging unarchivable objects
438   static OopHandle _scratch_basic_type_mirrors[T_VOID+1];
439   static MetaspaceObjToOopHandleTable* _scratch_objects_table;
440 
441   static void init_seen_objects_table() {
442     assert(_seen_objects_table == nullptr, "must be");
443     _seen_objects_table = new (mtClass)SeenObjectsTable(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
444   }
445   static void delete_seen_objects_table() {
446     assert(_seen_objects_table != nullptr, "must be");
447     delete _seen_objects_table;
448     _seen_objects_table = nullptr;
449   }
450 
451   class ContextMark;
452 
453   // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
454   static size_t _num_new_walked_objs;
455   static size_t _num_new_archived_objs;
456   static size_t _num_old_recorded_klasses;
457 
458   // Statistics (for all archived subgraphs)
459   static size_t _num_total_subgraph_recordings;
460   static size_t _num_total_walked_objs;
461   static size_t _num_total_archived_objs;
462   static size_t _num_total_recorded_klasses;
463   static size_t _num_total_verifications;
464 
465   static void start_recording_subgraph(InstanceKlass *k, const char* klass_name,
466                                        bool is_full_module_graph);
467   static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
468 
469   static bool has_been_seen_during_subgraph_recording(oop obj);
470   static void set_has_been_seen_during_subgraph_recording(oop obj);
471   static bool archive_object(oop obj, oop referrer, KlassSubGraphInfo* subgraph_info);
472 
473   static void resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]);
474   static void resolve_classes_for_subgraph_of(JavaThread* current, Klass* k);
475   static void clear_archived_roots_of(Klass* k);
476   static const ArchivedKlassSubGraphInfoRecord*
477                resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS);
478   static void resolve_or_init(const char* klass_name, bool do_init, TRAPS);
479   static void resolve_or_init(Klass* k, bool do_init, TRAPS);
480   static void init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record);
481 
482   static bool has_been_archived(oop orig_obj);
483   static void prepare_resolved_references();
484   static void archive_strings();
485   static void archive_subgraphs();
486   static void copy_java_mirror(oop orig_mirror, oop scratch_m);
487 
488   // PendingOop and PendingOopStack are used for recursively discovering all cacheable
489   // heap objects. The recursion is done using PendingOopStack so we won't overflow the
490   // C stack with deep reference chains.
491   class PendingOop {
492     oop _obj;
493     oop _referrer;
494     int _level;
495 
496   public:
497     PendingOop() : _obj(nullptr), _referrer(nullptr), _level(-1) {}
498     PendingOop(oop obj, oop referrer, int level) : _obj(obj), _referrer(referrer), _level(level) {}
499 
500     oop obj()      const { return _obj; }
501     oop referrer() const { return _referrer; }
502     int level()    const { return _level; }
503   };
504 
505   class OopFieldPusher;
506   using PendingOopStack = GrowableArrayCHeap<PendingOop, mtClassShared>;
507 
508   static PendingOop _object_being_archived;
509   static bool walk_one_object(PendingOopStack* stack, int level, KlassSubGraphInfo* subgraph_info,
510                               oop orig_obj, oop referrer);
511 
512  public:
513   static void exit_on_error();
514   static void reset_archived_object_states(TRAPS);
515   static void create_archived_object_cache() {
516     _archived_object_cache =
517       new (mtClass)ArchivedObjectCache(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
518   }
519   static void destroy_archived_object_cache() {
520     delete _archived_object_cache;
521     _archived_object_cache = nullptr;
522   }
523   static ArchivedObjectCache* archived_object_cache() {
524     return _archived_object_cache;
525   }
526 
527   static CachedOopInfo* get_cached_oop_info(oop orig_obj);
528 
529   static int archive_exception_instance(oop exception);
530 
531   static bool archive_reachable_objects_from(int level,
532                                              KlassSubGraphInfo* subgraph_info,
533                                              oop orig_obj);
534 
535   static bool is_dumped_interned_string(oop o);
536 
537   static void track_scratch_object(oop orig_obj, oop scratch_obj);
538 
539   // Scratch objects for archiving Klass::java_mirror()
540   static void set_scratch_java_mirror(Klass* k, oop mirror);
541   static void remove_scratch_objects(Klass* k);
542   static bool is_metadata_field(oop src_obj, int offset);
543   template <typename T> static void do_metadata_offsets(oop src_obj, T callback);
544   static void remap_dumped_metadata(oop src_obj, address archived_object);
545   inline static void remap_loaded_metadata(oop obj);
546   inline static oop maybe_remap_referent(bool is_java_lang_ref, size_t field_offset, oop referent);
547   static void get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers);
548   static void set_has_native_pointers(oop src_obj);
549   static uintptr_t archive_location(oop src_obj);
550 
551   // We use the HeapShared::roots() array to make sure that objects stored in the
552   // archived heap region are not prematurely collected. These roots include:
553   //
554   //    - mirrors of classes that have not yet been loaded.
555   //    - ConstantPool::resolved_references() of classes that have not yet been loaded.
556   //    - ArchivedKlassSubGraphInfoRecords that have not been initialized
557   //    - java.lang.Module objects that have not yet been added to the module graph
558   //
559   // When a mirror M becomes referenced by a newly loaded class K, M will be removed
560   // from HeapShared::roots() via clear_root(), and K will be responsible for
561   // keeping M alive.
562   //
563   // Other types of roots are also cleared similarly when they become referenced.
564 
565   // Dump-time only. Returns the index of the root, which can be used at run time to read
566   // the root using get_root(index, ...).
567   static int append_root(oop obj);
568   static GrowableArrayCHeap<OopHandle, mtClassShared>* pending_roots() { return _pending_roots; }
569 
570   // Dump-time and runtime
571   static objArrayOop root_segment(int segment_idx);
572   static oop get_root(int index, bool clear=false);
573 
574   // Run-time only
575   static void clear_root(int index);
576   static void get_segment_indexes(int index, int& segment_index, int& internal_index);
577   static void setup_test_class(const char* test_class_name) PRODUCT_RETURN;
578 #endif // INCLUDE_CDS_JAVA_HEAP
579 
580  public:
581   static void finish_materialize_objects() NOT_CDS_JAVA_HEAP_RETURN;
582 
583   static void write_heap(ArchiveMappedHeapInfo* mapped_heap_info, ArchiveStreamedHeapInfo* streamed_heap_info) NOT_CDS_JAVA_HEAP_RETURN;
584   static objArrayOop scratch_resolved_references(ConstantPool* src);
585   static void add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) NOT_CDS_JAVA_HEAP_RETURN;
586   static void init_dumping() NOT_CDS_JAVA_HEAP_RETURN;
587   static void init_scratch_objects_for_basic_type_mirrors(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
588   static void init_box_classes(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
589   static bool is_heap_region(int idx) {
590     CDS_JAVA_HEAP_ONLY(return (idx == AOTMetaspace::hp);)
591     NOT_CDS_JAVA_HEAP_RETURN_(false);
592   }
593   static void delete_tables_with_raw_oops() NOT_CDS_JAVA_HEAP_RETURN;
594 
595   static void resolve_classes(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN;
596   static void initialize_from_archived_subgraph(JavaThread* current, Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
597 
598   static void init_for_dumping(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
599   static void init_heap_writer() NOT_CDS_JAVA_HEAP_RETURN;
600   static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
601   static void serialize_tables(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
602 
603 #ifndef PRODUCT
604   static bool is_a_test_class_in_unnamed_module(Klass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
605   static void initialize_test_class_from_archive(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
606 #endif
607 
608   static void add_to_permanent_oop_table(oop obj, int offset);
609 
610   // AOT-compile time only: get a stable index for an archived object.
611   // Returns 0 if obj is not archived.
612   static int get_archived_object_permanent_index(oop obj) NOT_CDS_JAVA_HEAP_RETURN_(-1);
613   // Runtime only: get back the same object for an index returned by
614   // get_archived_object_permanent_index().
615   static oop get_archived_object(int permanent_index) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
616 
617   static void initialize_java_lang_invoke(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
618   static void init_classes_for_special_subgraph(Handle loader, TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
619 
620   static bool is_core_java_lang_invoke_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
621   static bool is_lambda_form_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
622   static bool is_lambda_proxy_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
623   static bool is_string_concat_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
624   static bool is_archivable_hidden_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
625 
626   // Used by AOTArtifactFinder
627   static void start_scanning_for_oops();
628   static void end_scanning_for_oops();
629   static void scan_java_class(Klass* k);
630   static void scan_java_mirror(oop orig_mirror);
631   static void copy_and_rescan_aot_inited_mirror(InstanceKlass* ik);
632   static void log_heap_roots();
633 
634   static intptr_t log_target_location(oop source_oop);
635   static void log_oop_info(outputStream* st, oop source_oop, address archived_object_start, address archived_object_end);
636   static void log_oop_info(outputStream* st, oop source_oop);
637   static void log_oop_details(oop source_oop, address buffered_addr);
638 };
639 
640 class CachedCodeDirectoryInternal {
641   int _permanent_oop_count;
642   int* _permanent_oop_offsets; // offset of each permanent object from the bottom of the archived heap
643 public:
644   void dumptime_init_internal() NOT_CDS_JAVA_HEAP_RETURN;
645   void runtime_init_internal() NOT_CDS_JAVA_HEAP_RETURN;
646 };
647 
648 #endif // SHARE_CDS_HEAPSHARED_HPP