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 #include "cds/aotMetaspace.hpp"
26 #include "cds/aotStreamedHeapLoader.hpp"
27 #include "cds/aotThread.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/filemap.hpp"
30 #include "cds/heapShared.inline.hpp"
31 #include "classfile/classLoaderDataShared.hpp"
32 #include "classfile/javaClasses.inline.hpp"
33 #include "classfile/stringTable.hpp"
34 #include "classfile/vmClasses.hpp"
35 #include "gc/shared/collectedHeap.inline.hpp"
36 #include "gc/shared/oopStorage.inline.hpp"
37 #include "gc/shared/oopStorageSet.inline.hpp"
38 #include "logging/log.hpp"
39 #include "memory/iterator.inline.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "oops/access.inline.hpp"
42 #include "oops/objArrayOop.inline.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "runtime/globals.hpp"
45 #include "runtime/globals_extension.hpp"
46 #include "runtime/handles.inline.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/mutex.hpp"
49 #include "runtime/thread.hpp"
50 #include "utilities/bitMap.inline.hpp"
51 #include "utilities/exceptions.hpp"
52 #include "utilities/globalDefinitions.hpp"
53 #include "utilities/stack.inline.hpp"
54 #include "utilities/ticks.hpp"
55
56 #include <type_traits>
57
58 #if INCLUDE_CDS_JAVA_HEAP
59
60 FileMapRegion* AOTStreamedHeapLoader::_heap_region;
61 FileMapRegion* AOTStreamedHeapLoader::_bitmap_region;
62 int* AOTStreamedHeapLoader::_roots_archive;
63 OopHandle AOTStreamedHeapLoader::_roots;
64 BitMapView AOTStreamedHeapLoader::_oopmap;
65 bool AOTStreamedHeapLoader::_is_in_use;
66 int AOTStreamedHeapLoader::_previous_batch_last_object_index;
67 int AOTStreamedHeapLoader::_current_batch_last_object_index;
68 int AOTStreamedHeapLoader::_current_root_index;
69 size_t AOTStreamedHeapLoader::_allocated_words;
70 bool AOTStreamedHeapLoader::_allow_gc;
71 bool AOTStreamedHeapLoader::_objects_are_handles;
72 size_t AOTStreamedHeapLoader::_num_archived_objects;
73 int AOTStreamedHeapLoader::_num_roots;
74 size_t AOTStreamedHeapLoader::_heap_region_used;
75 bool AOTStreamedHeapLoader::_loading_all_objects;
76
77 size_t* AOTStreamedHeapLoader::_object_index_to_buffer_offset_table;
78 void** AOTStreamedHeapLoader::_object_index_to_heap_object_table;
79 int* AOTStreamedHeapLoader::_root_highest_object_index_table;
80
81 bool AOTStreamedHeapLoader::_waiting_for_iterator;
82 bool AOTStreamedHeapLoader::_swapping_root_format;
83
84 static uint64_t _early_materialization_time_ns = 0;
85 static uint64_t _late_materialization_time_ns = 0;
86 static uint64_t _final_materialization_time_ns = 0;
87 static uint64_t _cleanup_materialization_time_ns = 0;
88 static volatile uint64_t _accumulated_lazy_materialization_time_ns = 0;
89 static Ticks _materialization_start_ticks;
90
91 int AOTStreamedHeapLoader::object_index_for_root_index(int root_index) {
92 return _roots_archive[root_index];
93 }
94
95 int AOTStreamedHeapLoader::highest_object_index_for_root_index(int root_index) {
96 return _root_highest_object_index_table[root_index];
97 }
98
99 size_t AOTStreamedHeapLoader::buffer_offset_for_object_index(int object_index) {
100 return _object_index_to_buffer_offset_table[object_index];
101 }
102
103 oopDesc* AOTStreamedHeapLoader::archive_object_for_object_index(int object_index) {
104 size_t buffer_offset = buffer_offset_for_object_index(object_index);
105 address bottom = (address)_heap_region->mapped_base();
106 return (oopDesc*)(bottom + buffer_offset);
107 }
108
109 size_t AOTStreamedHeapLoader::buffer_offset_for_archive_object(oopDesc* archive_object) {
110 address bottom = (address)_heap_region->mapped_base();
111 return size_t(archive_object) - size_t(bottom);
112 }
113
114 template <bool use_coops>
115 BitMap::idx_t AOTStreamedHeapLoader::obj_bit_idx_for_buffer_offset(size_t buffer_offset) {
116 if constexpr (use_coops) {
117 return BitMap::idx_t(buffer_offset / sizeof(narrowOop));
118 } else {
119 return BitMap::idx_t(buffer_offset / sizeof(HeapWord));
120 }
121 }
122
123 oop AOTStreamedHeapLoader::heap_object_for_object_index(int object_index) {
124 assert(object_index >= 0 && object_index <= (int)_num_archived_objects,
125 "Heap object reference out of index: %d", object_index);
126
127 if (_objects_are_handles) {
128 oop* handle = (oop*)_object_index_to_heap_object_table[object_index];
129 if (handle == nullptr) {
130 return nullptr;
131 }
132 return NativeAccess<>::oop_load(handle);
133 } else {
134 return cast_to_oop(_object_index_to_heap_object_table[object_index]);
135 }
136 }
137
138 void AOTStreamedHeapLoader::set_heap_object_for_object_index(int object_index, oop heap_object) {
139 assert(heap_object_for_object_index(object_index) == nullptr, "Should only set once with this API");
140 if (_objects_are_handles) {
141 oop* handle = Universe::vm_global()->allocate();
142 NativeAccess<>::oop_store(handle, heap_object);
143 _object_index_to_heap_object_table[object_index] = (void*)handle;
144 } else {
145 _object_index_to_heap_object_table[object_index] = cast_from_oop<void*>(heap_object);
146 }
147 }
148
149 int AOTStreamedHeapLoader::archived_string_value_object_index(oopDesc* archive_object) {
150 assert(archive_object->klass() == vmClasses::String_klass(), "Must be an archived string");
151 address archive_string_value_addr = (address)archive_object + java_lang_String::value_offset();
152 return UseCompressedOops ? *(int*)archive_string_value_addr : (int)*(int64_t*)archive_string_value_addr;
153 }
154
155 static int archive_array_length(oopDesc* archive_array) {
156 return *(int*)(address(archive_array) + arrayOopDesc::length_offset_in_bytes());
157 }
158
159 static size_t archive_object_size(oopDesc* archive_object) {
160 Klass* klass = archive_object->klass();
161 int lh = klass->layout_helper();
162
163 if (Klass::layout_helper_is_instance(lh)) {
164 // Instance
165 if (Klass::layout_helper_needs_slow_path(lh)) {
166 return ((size_t*)(archive_object))[-1];
167 } else {
168 return (size_t)Klass::layout_helper_size_in_bytes(lh) >> LogHeapWordSize;
169 }
170 } else if (Klass::layout_helper_is_array(lh)) {
171 // Array
172 size_t size_in_bytes;
173 size_t array_length = (size_t)archive_array_length(archive_object);
174 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
175 size_in_bytes += (size_t)Klass::layout_helper_header_size(lh);
176
177 return align_up(size_in_bytes, (size_t)MinObjAlignmentInBytes) / HeapWordSize;
178 } else {
179 // Other
180 return ((size_t*)(archive_object))[-1];
181 }
182 }
183
184 oop AOTStreamedHeapLoader::allocate_object(oopDesc* archive_object, markWord mark, size_t size, TRAPS) {
185 assert(!archive_object->is_stackChunk(), "no such objects are archived");
186
187 NoJvmtiEventsMark njem;
188 oop heap_object;
189
190 Klass* klass = archive_object->klass();
191 if (klass->is_mirror_instance_klass()) {
192 heap_object = Universe::heap()->class_allocate(klass, size, CHECK_NULL);
193 } else if (klass->is_instance_klass()) {
194 heap_object = Universe::heap()->obj_allocate(klass, size, CHECK_NULL);
195 } else {
196 assert(klass->is_array_klass(), "must be");
197 int length = archive_array_length(archive_object);
198 bool do_zero = klass->is_objArray_klass();
199 heap_object = Universe::heap()->array_allocate(klass, size, length, do_zero, CHECK_NULL);
200 }
201
202 heap_object->set_mark(mark);
203
204 return heap_object;
205 }
206
207 void AOTStreamedHeapLoader::install_root(int root_index, oop heap_object) {
208 objArrayOop roots = objArrayOop(_roots.resolve());
209 OrderAccess::release(); // Once the store below publishes an object, it can be concurrently picked up by another thread without using the lock
210 roots->obj_at_put(root_index, heap_object);
211 }
212
213 void AOTStreamedHeapLoader::TracingObjectLoader::wait_for_iterator() {
214 if (JavaThread::current()->is_active_Java_thread()) {
215 // When the main thread has bootstrapped past the point of allowing safepoints,
216 // we can and indeed have to use safepoint checking waiting.
217 AOTHeapLoading_lock->wait();
218 } else {
219 // If we have no bootstrapped the main thread far enough, then we cannot and
220 // indeed also don't need to perform safepoint checking waiting.
221 AOTHeapLoading_lock->wait_without_safepoint_check();
222 }
223 }
224
225 // Link object after copying in-place
226 template <typename LinkerT>
227 class AOTStreamedHeapLoader::InPlaceLinkingOopClosure : public BasicOopIterateClosure {
228 private:
229 oop _obj;
230 LinkerT _linker;
231
232 public:
233 InPlaceLinkingOopClosure(oop obj, LinkerT linker)
234 : _obj(obj),
235 _linker(linker) {
236 }
237
238 virtual void do_oop(oop* p) { do_oop_work(p, (int)*(intptr_t*)p); }
239 virtual void do_oop(narrowOop* p) { do_oop_work(p, *(int*)p); }
240
241 template <typename T>
242 void do_oop_work(T* p, int object_index) {
243 int p_offset = pointer_delta_as_int((address)p, cast_from_oop<address>(_obj));
244 oop pointee = _linker(p_offset, object_index);
245 if (pointee != nullptr) {
246 _obj->obj_field_put_access<IS_DEST_UNINITIALIZED>((int)p_offset, pointee);
247 }
248 }
249 };
250
251 template <bool use_coops, typename LinkerT>
252 void AOTStreamedHeapLoader::copy_payload_carefully(oopDesc* archive_object,
253 oop heap_object,
254 BitMap::idx_t header_bit,
255 BitMap::idx_t start_bit,
256 BitMap::idx_t end_bit,
257 LinkerT linker) {
258 using RawElementT = std::conditional_t<use_coops, int32_t, int64_t>;
259 using OopElementT = std::conditional_t<use_coops, narrowOop, oop>;
260
261 BitMap::idx_t unfinished_bit = start_bit;
262 BitMap::idx_t next_reference_bit = _oopmap.find_first_set_bit(unfinished_bit, end_bit);
263
264 // Fill in heap object bytes
265 while (unfinished_bit < end_bit) {
266 assert(unfinished_bit >= start_bit && unfinished_bit < end_bit, "out of bounds copying");
267
268 // This is the address of the pointee inside the input stream
269 size_t payload_offset = unfinished_bit - header_bit;
270 RawElementT* archive_payload_addr = ((RawElementT*)archive_object) + payload_offset;
271 RawElementT* heap_payload_addr = cast_from_oop<RawElementT*>(heap_object) + payload_offset;
272
273 assert(heap_payload_addr >= cast_from_oop<RawElementT*>(heap_object) &&
274 (HeapWord*)heap_payload_addr < cast_from_oop<HeapWord*>(heap_object) + heap_object->size(),
275 "Out of bounds copying");
276
277 if (next_reference_bit > unfinished_bit) {
278 // Primitive bytes available
279 size_t primitive_elements = next_reference_bit - unfinished_bit;
280 size_t primitive_bytes = primitive_elements * sizeof(RawElementT);
281 ::memcpy(heap_payload_addr, archive_payload_addr, primitive_bytes);
282
283 unfinished_bit = next_reference_bit;
284 } else {
285 // Encountered reference
286 RawElementT* archive_p = (RawElementT*)archive_payload_addr;
287 OopElementT* heap_p = (OopElementT*)heap_payload_addr;
288 int pointee_object_index = (int)*archive_p;
289 int heap_p_offset = pointer_delta_as_int((address)heap_p, cast_from_oop<address>(heap_object));
290
291 // The object index is retrieved from the archive, not the heap object. This is
292 // important after GC is enabled. Concurrent GC threads may scan references in the
293 // heap for various reasons after this point. Therefore, it is not okay to first copy
294 // the object index from a reference location in the archived object payload to a
295 // corresponding location in the heap object payload, and then fix it up afterwards to
296 // refer to a heap object. This is why this code iterates carefully over object references
297 // in the archived object, linking them one by one, without clobbering the reference
298 // locations in the heap objects with anything other than transitions from null to the
299 // intended linked object.
300 oop obj = linker(heap_p_offset, pointee_object_index);
301 if (obj != nullptr) {
302 heap_object->obj_field_put(heap_p_offset, obj);
303 }
304
305 unfinished_bit++;
306 next_reference_bit = _oopmap.find_first_set_bit(unfinished_bit, end_bit);
307 }
308 }
309 }
310
311 template <bool use_coops, typename LinkerT>
312 void AOTStreamedHeapLoader::copy_object_impl(oopDesc* archive_object,
313 oop heap_object,
314 size_t size,
315 LinkerT linker) {
316 if (!_allow_gc) {
317 // Without concurrent GC running, we can copy incorrect object references
318 // and metadata references into the heap object and then fix them up in-place.
319 size_t payload_size = size - 1;
320 HeapWord* archive_start = ((HeapWord*)archive_object) + 1;
321 HeapWord* heap_start = cast_from_oop<HeapWord*>(heap_object) + 1;
322
323 Copy::disjoint_words(archive_start, heap_start, payload_size);
324
325 // In-place linking fixes up object indices from references of the heap object,
326 // and patches them up to refer to objects. This can be done because we just copied
327 // the payload of the object from the archive to the heap object, including the
328 // reference object indices. However, this is only okay to do before the GC can run.
329 // A concurrent GC thread might racingly read the object payload after GC is enabled.
330 InPlaceLinkingOopClosure cl(heap_object, linker);
331 heap_object->oop_iterate(&cl);
332 HeapShared::remap_loaded_metadata(heap_object);
333 return;
334 }
335
336 // When a concurrent GC may be running, we take care not to copy incorrect oops,
337 // narrowOops or Metadata* into the heap objects. Transitions go from 0 to the
338 // intended runtime linked values only.
339 size_t word_scale = use_coops ? 2 : 1;
340 using RawElementT = std::conditional_t<use_coops, int32_t, int64_t>;
341
342 // Skip the markWord; it is set at allocation time
343 size_t header_size = word_scale;
344
345 size_t buffer_offset = buffer_offset_for_archive_object(archive_object);
346 const BitMap::idx_t header_bit = obj_bit_idx_for_buffer_offset<use_coops>(buffer_offset);
347 const BitMap::idx_t start_bit = header_bit + header_size;
348 const BitMap::idx_t end_bit = header_bit + size * word_scale;
349
350 BitMap::idx_t curr_bit = start_bit;
351
352 // We are a bit paranoid about GC or other safepointing operations observing
353 // shady metadata fields from the archive that do not point at real metadata.
354 // We deal with this by explicitly reading the requested address from the
355 // archive and fixing it to real Metadata before writing it into the heap object.
356 HeapShared::do_metadata_offsets(heap_object, [&](int metadata_offset) {
357 BitMap::idx_t metadata_field_idx = header_bit + (size_t)metadata_offset / sizeof(RawElementT);
358 BitMap::idx_t skip = word_scale;
359 assert(metadata_field_idx >= start_bit && metadata_field_idx + skip <= end_bit,
360 "Metadata field out of bounds");
361
362 // Copy payload before metadata field
363 copy_payload_carefully<use_coops>(archive_object,
364 heap_object,
365 header_bit,
366 curr_bit,
367 metadata_field_idx,
368 linker);
369
370 // Copy metadata field
371 Metadata* const archive_metadata = *(Metadata**)(uintptr_t(archive_object) + (size_t)metadata_offset);
372 Metadata* const runtime_metadata = archive_metadata != nullptr
373 ? (Metadata*)(address(archive_metadata) + AOTMetaspace::relocation_delta())
374 : nullptr;
375 assert(runtime_metadata == nullptr || AOTMetaspace::in_aot_cache(runtime_metadata), "Invalid metadata pointer");
376 DEBUG_ONLY(Metadata* const previous_metadata = heap_object->metadata_field(metadata_offset);)
377 assert(previous_metadata == nullptr || previous_metadata == runtime_metadata, "Should not observe transient values");
378 heap_object->metadata_field_put(metadata_offset, runtime_metadata);
379 curr_bit = metadata_field_idx + skip;
380 });
381
382 // Copy trailing metadata after the last metadata word. This is usually doing
383 // all the copying.
384 copy_payload_carefully<use_coops>(archive_object,
385 heap_object,
386 header_bit,
387 curr_bit,
388 end_bit,
389 linker);
390 }
391
392 void AOTStreamedHeapLoader::copy_object_eager_linking(oopDesc* archive_object, oop heap_object, size_t size) {
393 auto linker = [&](int p_offset, int pointee_object_index) {
394 oop obj = AOTStreamedHeapLoader::heap_object_for_object_index(pointee_object_index);
395 assert(pointee_object_index == 0 || obj != nullptr, "Eager object loading should only encounter already allocated links");
396 return obj;
397 };
398 if (UseCompressedOops) {
399 copy_object_impl<true>(archive_object, heap_object, size, linker);
400 } else {
401 copy_object_impl<false>(archive_object, heap_object, size, linker);
402 }
403 }
404
405 void AOTStreamedHeapLoader::TracingObjectLoader::copy_object_lazy_linking(int object_index,
406 oopDesc* archive_object,
407 oop heap_object,
408 size_t size,
409 Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack) {
410 auto linker = [&](int p_offset, int pointee_object_index) {
411 dfs_stack.push({pointee_object_index, object_index, p_offset});
412
413 // The tracing linker is a bit lazy and mutates the reference fields in its traversal.
414 // Returning null means don't link now.
415 return oop(nullptr);
416 };
417 if (UseCompressedOops) {
418 copy_object_impl<true>(archive_object, heap_object, size, linker);
419 } else {
420 copy_object_impl<false>(archive_object, heap_object, size, linker);
421 }
422 }
423
424 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_object_inner(int object_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
425 // Allocate object
426 oopDesc* archive_object = archive_object_for_object_index(object_index);
427 size_t size = archive_object_size(archive_object);
428 markWord mark = archive_object->mark();
429
430 // The markWord is marked if the object is a String and it should be interned,
431 // make sure to unmark it before allocating memory for the object.
432 bool string_intern = mark.is_marked();
433 mark = mark.set_unmarked();
434
435 oop heap_object;
436
437 if (string_intern) {
438 int value_object_index = archived_string_value_object_index(archive_object);
439
440 // Materialize the value object.
441 (void)materialize_object(value_object_index, dfs_stack, CHECK_NULL);
442
443 // Allocate and link the string.
444 heap_object = allocate_object(archive_object, mark, size, CHECK_NULL);
445 copy_object_eager_linking(archive_object, heap_object, size);
446
447 assert(java_lang_String::value(heap_object) == heap_object_for_object_index(value_object_index), "Linker should have linked this correctly");
448
449 // Replace the string with interned string
450 heap_object = StringTable::intern(heap_object, CHECK_NULL);
451 } else {
452 heap_object = allocate_object(archive_object, mark, size, CHECK_NULL);
453
454 // Fill in object contents
455 copy_object_lazy_linking(object_index, archive_object, heap_object, size, dfs_stack);
456 }
457
458 // Install forwarding
459 set_heap_object_for_object_index(object_index, heap_object);
460
461 return heap_object;
462 }
463
464 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_object(int object_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
465 if (object_index <= _previous_batch_last_object_index) {
466 // The transitive closure of this object has been materialized; no need to do anything
467 return heap_object_for_object_index(object_index);
468 }
469
470 if (object_index <= _current_batch_last_object_index) {
471 // The AOTThread is currently materializing this object and its transitive closure; only need to wait for it to complete
472 _waiting_for_iterator = true;
473 while (object_index > _previous_batch_last_object_index) {
474 wait_for_iterator();
475 }
476 _waiting_for_iterator = false;
477
478 // Notify the AOT thread if it is waiting for tracing to finish
479 AOTHeapLoading_lock->notify_all();
480 return heap_object_for_object_index(object_index);;
481 }
482
483 oop heap_object = heap_object_for_object_index(object_index);
484 if (heap_object != nullptr) {
485 // Already materialized by mutator
486 return heap_object;
487 }
488
489 return materialize_object_inner(object_index, dfs_stack, THREAD);
490 }
491
492 void AOTStreamedHeapLoader::TracingObjectLoader::drain_stack(Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
493 while (!dfs_stack.is_empty()) {
494 AOTHeapTraversalEntry entry = dfs_stack.pop();
495 int pointee_object_index = entry._pointee_object_index;
496 oop pointee_heap_object = materialize_object(pointee_object_index, dfs_stack, CHECK);
497 oop heap_object = heap_object_for_object_index(entry._base_object_index);
498 if (_allow_gc) {
499 heap_object->obj_field_put(entry._heap_field_offset_bytes, pointee_heap_object);
500 } else {
501 heap_object->obj_field_put_access<IS_DEST_UNINITIALIZED>(entry._heap_field_offset_bytes, pointee_heap_object);
502 }
503 }
504 }
505
506 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_object_transitive(int object_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
507 assert_locked_or_safepoint(AOTHeapLoading_lock);
508 while (_waiting_for_iterator) {
509 wait_for_iterator();
510 }
511
512 auto handlized_materialize_object = [&](TRAPS) {
513 oop obj = materialize_object(object_index, dfs_stack, CHECK_(Handle()));
514 return Handle(THREAD, obj);
515 };
516
517 Handle result = handlized_materialize_object(CHECK_NULL);
518 drain_stack(dfs_stack, CHECK_NULL);
519
520 return result();
521 }
522
523 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_root(int root_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
524 int root_object_index = object_index_for_root_index(root_index);
525 oop root = materialize_object_transitive(root_object_index, dfs_stack, CHECK_NULL);
526 install_root(root_index, root);
527
528 return root;
529 }
530
531 int oop_handle_cmp(const void* left, const void* right) {
532 oop* left_handle = *(oop**)left;
533 oop* right_handle = *(oop**)right;
534
535 if (right_handle > left_handle) {
536 return -1;
537 } else if (left_handle > right_handle) {
538 return 1;
539 }
540
541 return 0;
542 }
543
544 // The range is inclusive
545 void AOTStreamedHeapLoader::IterativeObjectLoader::initialize_range(int first_object_index, int last_object_index, TRAPS) {
546 for (int i = first_object_index; i <= last_object_index; ++i) {
547 oopDesc* archive_object = archive_object_for_object_index(i);
548 markWord mark = archive_object->mark();
549 bool string_intern = mark.is_marked();
550 if (string_intern) {
551 int value_object_index = archived_string_value_object_index(archive_object);
552 if (value_object_index == i + 1) {
553 // Interned strings are eagerly materialized in the allocation phase, so there is
554 // nothing else to do for interned strings here for the string nor its value array.
555 i++;
556 }
557 continue;
558 }
559 size_t size = archive_object_size(archive_object);
560 oop heap_object = heap_object_for_object_index(i);
561 copy_object_eager_linking(archive_object, heap_object, size);
562 }
563 }
564
565 // The range is inclusive
566 size_t AOTStreamedHeapLoader::IterativeObjectLoader::materialize_range(int first_object_index, int last_object_index, TRAPS) {
567 GrowableArrayCHeap<int, mtClassShared> lazy_object_indices(0);
568 size_t materialized_words = 0;
569
570 for (int i = first_object_index; i <= last_object_index; ++i) {
571 oopDesc* archive_object = archive_object_for_object_index(i);
572 markWord mark = archive_object->mark();
573
574 // The markWord is marked if the object is a String and it should be interned,
575 // make sure to unmark it before allocating memory for the object.
576 bool string_intern = mark.is_marked();
577 mark = mark.set_unmarked();
578
579 size_t size = archive_object_size(archive_object);
580 materialized_words += size;
581
582 oop heap_object = heap_object_for_object_index(i);
583 if (heap_object != nullptr) {
584 // Lazy loading has already initialized the object; we must not mutate it
585 lazy_object_indices.append(i);
586 continue;
587 }
588
589 if (!string_intern) {
590 // The normal case; no lazy loading have loaded the object yet
591 heap_object = allocate_object(archive_object, mark, size, CHECK_0);
592 set_heap_object_for_object_index(i, heap_object);
593 continue;
594 }
595
596 // Eagerly materialize interned strings to ensure that objects earlier than the string
597 // in a batch get linked to the intended interned string, and not a copy.
598 int value_object_index = archived_string_value_object_index(archive_object);
599
600 bool is_normal_interned_string = value_object_index == i + 1;
601
602 if (value_object_index < first_object_index) {
603 // If materialized in a previous batch, the value should already be allocated and initialized.
604 assert(heap_object_for_object_index(value_object_index) != nullptr, "should be materialized");
605 } else {
606 // Materialize the value object.
607 oopDesc* archive_value_object = archive_object_for_object_index(value_object_index);
608 markWord value_mark = archive_value_object->mark();
609 size_t value_size = archive_object_size(archive_value_object);
610 oop value_heap_object;
611
612 if (is_normal_interned_string) {
613 // The common case: the value is next to the string. This happens when only the interned
614 // string points to its value character array.
615 assert(value_object_index <= last_object_index, "Must be within this batch: %d <= %d", value_object_index, last_object_index);
616 value_heap_object = allocate_object(archive_value_object, value_mark, value_size, CHECK_0);
617 set_heap_object_for_object_index(value_object_index, value_heap_object);
618 materialized_words += value_size;
619 } else {
620 // In the uncommon case, multiple strings point to the value of an interned string.
621 // The string can then be earlier in the batch.
622 assert(value_object_index < i, "surprising index");
623 value_heap_object = heap_object_for_object_index(value_object_index);
624 }
625
626 copy_object_eager_linking(archive_value_object, value_heap_object, value_size);
627 }
628 // Allocate and link the string.
629 heap_object = allocate_object(archive_object, mark, size, CHECK_0);
630 copy_object_eager_linking(archive_object, heap_object, size);
631
632 assert(java_lang_String::value(heap_object) == heap_object_for_object_index(value_object_index), "Linker should have linked this correctly");
633
634 // Replace the string with interned string
635 heap_object = StringTable::intern(heap_object, CHECK_0);
636 set_heap_object_for_object_index(i, heap_object);
637
638 if (is_normal_interned_string) {
639 // Skip over the string value, already materialized
640 i++;
641 }
642 }
643
644 if (lazy_object_indices.is_empty()) {
645 // Normal case; no sprinkled lazy objects in the root subgraph
646 initialize_range(first_object_index, last_object_index, CHECK_0);
647 } else {
648 // The user lazy initialized some objects that are already initialized; we have to initialize around them
649 // to make sure they are not mutated.
650 int previous_object_index = first_object_index - 1; // Exclusive start of initialization slice
651 for (int i = 0; i < lazy_object_indices.length(); ++i) {
652 int lazy_object_index = lazy_object_indices.at(i);
653 int slice_start_object_index = previous_object_index;
654 int slice_end_object_index = lazy_object_index;
655
656 if (slice_end_object_index - slice_start_object_index > 1) { // Both markers are exclusive
657 initialize_range(slice_start_object_index + 1, slice_end_object_index - 1, CHECK_0);
658 }
659 previous_object_index = lazy_object_index;
660 }
661 // Process tail range
662 if (last_object_index - previous_object_index > 0) {
663 initialize_range(previous_object_index + 1, last_object_index, CHECK_0);
664 }
665 }
666
667 return materialized_words;
668 }
669
670 bool AOTStreamedHeapLoader::IterativeObjectLoader::has_more() {
671 return _current_root_index < _num_roots;
672 }
673
674 void AOTStreamedHeapLoader::IterativeObjectLoader::materialize_next_batch(TRAPS) {
675 assert(has_more(), "only materialize if there is something to materialize");
676
677 int min_batch_objects = 128;
678 int from_root_index = _current_root_index;
679 int max_to_root_index = _num_roots - 1;
680 int until_root_index = from_root_index;
681 int highest_object_index;
682
683 // Expand the batch size from one root, to N roots until we cross 128 objects in total
684 for (;;) {
685 highest_object_index = highest_object_index_for_root_index(until_root_index);
686 if (highest_object_index - _previous_batch_last_object_index >= min_batch_objects) {
687 break;
688 }
689 if (until_root_index == max_to_root_index) {
690 break;
691 }
692 until_root_index++;
693 }
694
695 oop root = nullptr;
696
697 // Materialize objects of necessary, representing the transitive closure of the root
698 if (highest_object_index > _previous_batch_last_object_index) {
699 while (_swapping_root_format) {
700 // When the roots are being upgraded to use handles, it is not safe to racingly
701 // iterate over the object; we must wait. Setting the current batch last object index
702 // to something other than the previous batch last object index indicates to the
703 // root swapping that there is current iteration ongoing.
704 AOTHeapLoading_lock->wait();
705 }
706 int first_object_index = _previous_batch_last_object_index + 1;
707 _current_batch_last_object_index = highest_object_index;
708 size_t allocated_words;
709 {
710 MutexUnlocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
711 allocated_words = materialize_range(first_object_index, highest_object_index, CHECK);
712 }
713 _allocated_words += allocated_words;
714 _previous_batch_last_object_index = _current_batch_last_object_index;
715 if (_waiting_for_iterator) {
716 // If tracer is waiting, let it know at the next point of unlocking that the root
717 // set it waited for has been processed now.
718 AOTHeapLoading_lock->notify_all();
719 }
720 }
721
722 // Install the root
723 for (int i = from_root_index; i <= until_root_index; ++i) {
724 int root_object_index = object_index_for_root_index(i);
725 root = heap_object_for_object_index(root_object_index);
726 install_root(i, root);
727 ++_current_root_index;
728 }
729 }
730
731 bool AOTStreamedHeapLoader::materialize_early(TRAPS) {
732 Ticks start = Ticks::now();
733
734 // Only help with early materialization from the AOT thread if the heap archive can be allocated
735 // without the need for a GC. Otherwise, do lazy loading until GC is enabled later in the bootstrapping.
736 size_t bootstrap_max_memory = Universe::heap()->bootstrap_max_memory();
737 size_t bootstrap_min_memory = MAX2(_heap_region_used, 2 * M);
738
739 size_t before_gc_materialize_budget_bytes = (bootstrap_max_memory > bootstrap_min_memory) ? bootstrap_max_memory - bootstrap_min_memory : 0;
740 size_t before_gc_materialize_budget_words = before_gc_materialize_budget_bytes / HeapWordSize;
741
742 log_info(aot, heap)("Max bootstrapping memory: %zuM, min bootstrapping memory: %zuM, selected budget: %zuM",
743 bootstrap_max_memory / M, bootstrap_min_memory / M, before_gc_materialize_budget_bytes / M);
744
745 while (IterativeObjectLoader::has_more()) {
746 if (_allow_gc || _allocated_words > before_gc_materialize_budget_words) {
747 log_info(aot, heap)("Early object materialization interrupted at root %d", _current_root_index);
748 break;
749 }
750
751 IterativeObjectLoader::materialize_next_batch(CHECK_false);
752 }
753
754 _early_materialization_time_ns = (Ticks::now() - start).nanoseconds();
755
756 bool finished_before_gc_allowed = !_allow_gc && !IterativeObjectLoader::has_more();
757
758 return finished_before_gc_allowed;
759 }
760
761 void AOTStreamedHeapLoader::materialize_late(TRAPS) {
762 Ticks start = Ticks::now();
763
764 // Continue materializing with GC allowed
765
766 while (IterativeObjectLoader::has_more()) {
767 IterativeObjectLoader::materialize_next_batch(CHECK);
768 }
769
770 _late_materialization_time_ns = (Ticks::now() - start).nanoseconds();
771 }
772
773 void AOTStreamedHeapLoader::cleanup() {
774 // First ensure there is no concurrent tracing going on
775 while (_waiting_for_iterator) {
776 AOTHeapLoading_lock->wait();
777 }
778
779 Ticks start = Ticks::now();
780
781 // Remove OopStorage roots
782 if (_objects_are_handles) {
783 size_t num_handles = _num_archived_objects;
784 // Skip the null entry
785 oop** handles = ((oop**)_object_index_to_heap_object_table) + 1;
786 // Sort the handles so that oop storage can release them faster
787 qsort(handles, num_handles, sizeof(oop*), (int (*)(const void*, const void*))oop_handle_cmp);
788 size_t num_null_handles = 0;
789 for (size_t handles_remaining = num_handles; handles_remaining != 0; --handles_remaining) {
790 oop* handle = handles[handles_remaining - 1];
791 if (handle == nullptr) {
792 num_null_handles = handles_remaining;
793 break;
794 }
795 NativeAccess<>::oop_store(handle, nullptr);
796 }
797 Universe::vm_global()->release(&handles[num_null_handles], num_handles - num_null_handles);
798 }
799
800 FREE_C_HEAP_ARRAY(void*, _object_index_to_heap_object_table);
801
802 // Unmap regions
803 FileMapInfo::current_info()->unmap_region(AOTMetaspace::hp);
804 FileMapInfo::current_info()->unmap_region(AOTMetaspace::bm);
805
806 _cleanup_materialization_time_ns = (Ticks::now() - start).nanoseconds();
807
808 log_statistics();
809 }
810
811 void AOTStreamedHeapLoader::log_statistics() {
812 uint64_t total_duration_us = (Ticks::now() - _materialization_start_ticks).microseconds();
813 const bool is_async = _loading_all_objects && !AOTEagerlyLoadObjects;
814 const char* const async_or_sync = is_async ? "async" : "sync";
815 log_info(aot, heap)("start to finish materialization time: " UINT64_FORMAT "us",
816 total_duration_us);
817 log_info(aot, heap)("early object materialization time (%s): " UINT64_FORMAT "us",
818 async_or_sync, _early_materialization_time_ns / 1000);
819 log_info(aot, heap)("late object materialization time (%s): " UINT64_FORMAT "us",
820 async_or_sync, _late_materialization_time_ns / 1000);
821 log_info(aot, heap)("object materialization cleanup time (%s): " UINT64_FORMAT "us",
822 async_or_sync, _cleanup_materialization_time_ns / 1000);
823 log_info(aot, heap)("final object materialization time stall (sync): " UINT64_FORMAT "us",
824 _final_materialization_time_ns / 1000);
825 log_info(aot, heap)("bootstrapping lazy materialization time (sync): " UINT64_FORMAT "us",
826 _accumulated_lazy_materialization_time_ns / 1000);
827
828 uint64_t sync_time = _final_materialization_time_ns + _accumulated_lazy_materialization_time_ns;
829 uint64_t async_time = _early_materialization_time_ns + _late_materialization_time_ns + _cleanup_materialization_time_ns;
830
831 if (!is_async) {
832 sync_time += async_time;
833 async_time = 0;
834 }
835
836 log_info(aot, heap)("sync materialization time: " UINT64_FORMAT "us",
837 sync_time / 1000);
838
839 log_info(aot, heap)("async materialization time: " UINT64_FORMAT "us",
840 async_time / 1000);
841
842 uint64_t iterative_time = (uint64_t)(is_async ? async_time : sync_time);
843 uint64_t materialized_bytes = _allocated_words * HeapWordSize;
844 log_info(aot, heap)("%s materialized " UINT64_FORMAT "K (" UINT64_FORMAT "M/s)", async_or_sync,
845 materialized_bytes / 1024, uint64_t(materialized_bytes * UCONST64(1'000'000'000) / M / iterative_time));
846 }
847
848 void AOTStreamedHeapLoader::materialize_objects() {
849 // We cannot handle any exception when materializing roots. Exits the VM.
850 EXCEPTION_MARK
851
852 // Objects are laid out in DFS order; DFS traverse the roots by linearly walking all objects
853 HandleMark hm(THREAD);
854
855 // Early materialization with a budget before GC is allowed
856 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
857
858 materialize_early(CHECK);
859 await_gc_enabled();
860 materialize_late(CHECK);
861 // Notify materialization is done
862 AOTHeapLoading_lock->notify_all();
863 cleanup();
864 }
865
866 void AOTStreamedHeapLoader::switch_object_index_to_handle(int object_index) {
867 oop heap_object = cast_to_oop(_object_index_to_heap_object_table[object_index]);
868 if (heap_object == nullptr) {
869 return;
870 }
871
872 oop* handle = Universe::vm_global()->allocate();
873 NativeAccess<>::oop_store(handle, heap_object);
874 _object_index_to_heap_object_table[object_index] = handle;
875 }
876
877 void AOTStreamedHeapLoader::enable_gc() {
878 if (AOTEagerlyLoadObjects && !IterativeObjectLoader::has_more()) {
879 // Everything was loaded eagerly at early startup
880 return;
881 }
882
883 // We cannot handle any exception when materializing roots. Exits the VM.
884 EXCEPTION_MARK
885
886 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
887
888 // First wait until no tracing is active
889 while (_waiting_for_iterator) {
890 AOTHeapLoading_lock->wait();
891 }
892
893 // Lock further tracing from starting
894 _waiting_for_iterator = true;
895
896 // Record iterator progress
897 int num_handles = (int)_num_archived_objects;
898
899 // Lock further iteration from starting
900 _swapping_root_format = true;
901
902 // Then wait for the iterator to stop
903 while (_previous_batch_last_object_index != _current_batch_last_object_index) {
904 AOTHeapLoading_lock->wait();
905 }
906
907 if (IterativeObjectLoader::has_more()) {
908 // If there is more to be materialized, we have to upgrade the object index
909 // to object mapping to use handles. If there isn't more to materialize, the
910 // handle will no longer e used; they are only used to materialize objects.
911
912 for (int i = 1; i <= num_handles; ++i) {
913 // Upgrade the roots to use handles
914 switch_object_index_to_handle(i);
915 }
916
917 // From now on, accessing the object table must be done through a handle.
918 _objects_are_handles = true;
919 }
920
921 // Unlock tracing
922 _waiting_for_iterator = false;
923
924 // Unlock iteration
925 _swapping_root_format = false;
926
927 _allow_gc = true;
928
929 AOTHeapLoading_lock->notify_all();
930
931 if (AOTEagerlyLoadObjects && IterativeObjectLoader::has_more()) {
932 materialize_late(CHECK);
933 cleanup();
934 }
935 }
936
937 void AOTStreamedHeapLoader::materialize_thread_object() {
938 AOTThread::materialize_thread_object();
939 }
940
941 void AOTStreamedHeapLoader::finish_materialize_objects() {
942 Ticks start = Ticks::now();
943
944 if (_loading_all_objects) {
945 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
946 // Wait for the AOT thread to finish
947 while (IterativeObjectLoader::has_more()) {
948 AOTHeapLoading_lock->wait();
949 }
950 } else {
951 assert(!AOTEagerlyLoadObjects, "sanity");
952 assert(_current_root_index == 0, "sanity");
953 // Without the full module graph we have done only lazy tracing materialization.
954 // Ensure all roots are processed here by triggering root loading on every root.
955 for (int i = 0; i < _num_roots; ++i) {
956 get_root(i);
957 }
958 cleanup();
959 }
960
961 _final_materialization_time_ns = (Ticks::now() - start).nanoseconds();
962 }
963
964 void account_lazy_materialization_time_ns(uint64_t time, const char* description, int index) {
965 AtomicAccess::add(&_accumulated_lazy_materialization_time_ns, time);
966 log_debug(aot, heap)("Lazy materialization of %s: %d end (" UINT64_FORMAT " us of " UINT64_FORMAT " us)", description, index, time / 1000, _accumulated_lazy_materialization_time_ns / 1000);
967 }
968
969 // Initialize an empty array of AOT heap roots; materialize them lazily
970 void AOTStreamedHeapLoader::initialize() {
971 EXCEPTION_MARK
972
973 _materialization_start_ticks = Ticks::now();
974
975 FileMapInfo::current_info()->map_bitmap_region();
976
977 _heap_region = FileMapInfo::current_info()->region_at(AOTMetaspace::hp);
978 _bitmap_region = FileMapInfo::current_info()->region_at(AOTMetaspace::bm);
979
980 assert(_heap_region->used() > 0, "empty heap archive?");
981
982 _is_in_use = true;
983
984 // archived roots are at this offset in the stream.
985 size_t roots_offset = FileMapInfo::current_info()->streamed_heap()->roots_offset();
986 size_t forwarding_offset = FileMapInfo::current_info()->streamed_heap()->forwarding_offset();
987 size_t root_highest_object_index_table_offset = FileMapInfo::current_info()->streamed_heap()->root_highest_object_index_table_offset();
988 _num_archived_objects = FileMapInfo::current_info()->streamed_heap()->num_archived_objects();
989
990 // The first int is the length of the array
991 _roots_archive = ((int*)(((address)_heap_region->mapped_base()) + roots_offset)) + 1;
992 _num_roots = _roots_archive[-1];
993 _heap_region_used = _heap_region->used();
994
995 // We can't retire a TLAB until the filler klass is set; set it to the archived object klass.
996 CollectedHeap::set_filler_object_klass(vmClasses::Object_klass());
997
998 objArrayOop roots = oopFactory::new_objectArray(_num_roots, CHECK);
999 _roots = OopHandle(Universe::vm_global(), roots);
1000
1001 _object_index_to_buffer_offset_table = (size_t*)(((address)_heap_region->mapped_base()) + forwarding_offset);
1002 // We allocate the first entry for "null"
1003 _object_index_to_heap_object_table = NEW_C_HEAP_ARRAY(void*, _num_archived_objects + 1, mtClassShared);
1004 Copy::zero_to_bytes(_object_index_to_heap_object_table, (_num_archived_objects + 1) * sizeof(void*));
1005
1006 _root_highest_object_index_table = (int*)(((address)_heap_region->mapped_base()) + root_highest_object_index_table_offset);
1007
1008 address start = (address)(_bitmap_region->mapped_base()) + _heap_region->oopmap_offset();
1009 _oopmap = BitMapView((BitMap::bm_word_t*)start, _heap_region->oopmap_size_in_bits());
1010
1011
1012 if (FLAG_IS_DEFAULT(AOTEagerlyLoadObjects)) {
1013 // Concurrency will not help much if there are no extra cores available.
1014 FLAG_SET_ERGO(AOTEagerlyLoadObjects, os::initial_active_processor_count() <= 1);
1015 }
1016
1017 // If the full module graph is not available or the JVMTI class file load hook is on, we
1018 // will prune the object graph to not include cached objects in subgraphs that are not intended
1019 // to be loaded.
1020 _loading_all_objects = CDSConfig::is_using_full_module_graph() && !JvmtiExport::should_post_class_file_load_hook();
1021 if (!_loading_all_objects) {
1022 // When not using FMG, fall back to tracing materialization
1023 FLAG_SET_ERGO(AOTEagerlyLoadObjects, false);
1024 return;
1025 }
1026
1027 if (AOTEagerlyLoadObjects) {
1028 // Objects are laid out in DFS order; DFS traverse the roots by linearly walking all objects
1029 HandleMark hm(THREAD);
1030
1031 // Early materialization with a budget before GC is allowed
1032 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
1033
1034 bool finished_before_gc_allowed = materialize_early(CHECK);
1035 if (finished_before_gc_allowed) {
1036 cleanup();
1037 }
1038 } else {
1039 AOTThread::initialize();
1040 }
1041 }
1042
1043 oop AOTStreamedHeapLoader::materialize_root(int root_index) {
1044 Ticks start = Ticks::now();
1045 // We cannot handle any exception when materializing a root. Exits the VM.
1046 EXCEPTION_MARK
1047 Stack<AOTHeapTraversalEntry, mtClassShared> dfs_stack;
1048 HandleMark hm(THREAD);
1049
1050 oop result;
1051 {
1052 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
1053
1054 oop root = objArrayOop(_roots.resolve())->obj_at(root_index);
1055
1056 if (root != nullptr) {
1057 // The root has already been materialized
1058 result = root;
1059 } else {
1060 // The root has not been materialized, start tracing materialization
1061 result = TracingObjectLoader::materialize_root(root_index, dfs_stack, CHECK_NULL);
1062 }
1063 }
1064
1065 uint64_t duration = (Ticks::now() - start).nanoseconds();
1066
1067 account_lazy_materialization_time_ns(duration, "root", root_index);
1068
1069 return result;
1070 }
1071
1072 oop AOTStreamedHeapLoader::get_root(int index) {
1073 oop result = objArrayOop(_roots.resolve())->obj_at(index);
1074 if (result == nullptr) {
1075 // Materialize root
1076 result = materialize_root(index);
1077 }
1078 if (result == _roots.resolve()) {
1079 // A self-reference to the roots array acts as a sentinel object for null,
1080 // indicating that the root has been cleared.
1081 result = nullptr;
1082 }
1083 // Acquire the root transitive object payload
1084 OrderAccess::acquire();
1085 return result;
1086 }
1087
1088 void AOTStreamedHeapLoader::clear_root(int index) {
1089 // Self-reference to the roots array acts as a sentinel object for null,
1090 // indicating that the root has been cleared.
1091 objArrayOop(_roots.resolve())->obj_at_put(index, _roots.resolve());
1092 }
1093
1094 void AOTStreamedHeapLoader::await_gc_enabled() {
1095 while (!_allow_gc) {
1096 AOTHeapLoading_lock->wait();
1097 }
1098 }
1099
1100 void AOTStreamedHeapLoader::finish_initialization(FileMapInfo* static_mapinfo) {
1101 static_mapinfo->stream_heap_region();
1102 }
1103
1104 AOTMapLogger::OopDataIterator* AOTStreamedHeapLoader::oop_iterator(FileMapInfo* info, address buffer_start, address buffer_end) {
1105 class StreamedLoaderOopIterator : public AOTMapLogger::OopDataIterator {
1106 private:
1107 int _current;
1108 int _next;
1109
1110 address _buffer_start;
1111
1112 int _num_archived_objects;
1113
1114 public:
1115 StreamedLoaderOopIterator(address buffer_start,
1116 int num_archived_objects)
1117 : _current(0),
1118 _next(1),
1119 _buffer_start(buffer_start),
1120 _num_archived_objects(num_archived_objects) {
1121 }
1122
1123 AOTMapLogger::OopData capture(int dfs_index) {
1124 size_t buffered_offset = buffer_offset_for_object_index(dfs_index);
1125 address buffered_addr = _buffer_start + buffered_offset;
1126 oopDesc* raw_oop = (oopDesc*)buffered_addr;
1127 size_t size = archive_object_size(raw_oop);
1128
1129 intptr_t target_location = (intptr_t)buffered_offset;
1130 uint32_t narrow_location = checked_cast<uint32_t>(dfs_index);
1131 Klass* klass = raw_oop->klass();
1132
1133 address requested_addr = (address)buffered_offset;
1134
1135 return { buffered_addr,
1136 requested_addr,
1137 target_location,
1138 narrow_location,
1139 raw_oop,
1140 klass,
1141 size,
1142 false };
1143 }
1144
1145 bool has_next() override {
1146 return _next <= _num_archived_objects;
1147 }
1148
1149 AOTMapLogger::OopData next() override {
1150 _current = _next;
1151 AOTMapLogger::OopData result = capture(_current);
1152 _next = _current + 1;
1153 return result;
1154 }
1155
1156 AOTMapLogger::OopData obj_at(narrowOop* addr) override {
1157 int dfs_index = (int)(*addr);
1158 if (dfs_index == 0) {
1159 return null_data();
1160 } else {
1161 return capture(dfs_index);
1162 }
1163 }
1164
1165 AOTMapLogger::OopData obj_at(oop* addr) override {
1166 int dfs_index = (int)cast_from_oop<uintptr_t>(*addr);
1167 if (dfs_index == 0) {
1168 return null_data();
1169 } else {
1170 return capture(dfs_index);
1171 }
1172 }
1173
1174 GrowableArrayCHeap<AOTMapLogger::OopData, mtClass>* roots() override {
1175 GrowableArrayCHeap<AOTMapLogger::OopData, mtClass>* result = new GrowableArrayCHeap<AOTMapLogger::OopData, mtClass>();
1176
1177 for (int i = 0; i < _num_roots; ++i) {
1178 int object_index = object_index_for_root_index(i);
1179 result->append(capture(object_index));
1180 }
1181
1182 return result;
1183 }
1184 };
1185
1186 assert(_is_in_use, "printing before initializing?");
1187
1188 return new StreamedLoaderOopIterator(buffer_start, (int)info->streamed_heap()->num_archived_objects());
1189 }
1190
1191 #endif // INCLUDE_CDS_JAVA_HEAP