1 /*
2 * Copyright (c) 2018, 2026, 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 // archive_object lives in CDS mapped memory, not in the GC heap.
160 // Calling expand_for_hash() converts the raw oopDesc* to an oop, which
161 // triggers oop verification. ZGC's verifier rejects non-heap addresses,
162 // so we must suspend the check for that call.
163 #ifdef CHECK_UNHANDLED_OOPS
164 class SuspendCheckOopFunction : public StackObj {
165 CheckOopFunctionPointer _saved;
166 public:
167 SuspendCheckOopFunction() : _saved(check_oop_function) { check_oop_function = nullptr; }
168 ~SuspendCheckOopFunction() { check_oop_function = _saved; }
169 };
170 #endif
171
172 static bool archive_expand_for_hash(Klass* klass, oopDesc* archive_object) {
173 CHECK_UNHANDLED_OOPS_ONLY(SuspendCheckOopFunction suspend;)
174 return klass->expand_for_hash(archive_object, archive_object->mark());
175 }
176
177 static size_t archive_object_size(oopDesc* archive_object) {
178 Klass* klass = archive_object->klass();
179 int lh = klass->layout_helper();
180
181 if (Klass::layout_helper_is_instance(lh)) {
182 // Instance
183 if (Klass::layout_helper_needs_slow_path(lh)) {
184 return ((size_t*)(archive_object))[-1];
185 } else {
186 size_t size = (size_t)Klass::layout_helper_size_in_bytes(lh) >> LogHeapWordSize;
187 if (UseCompactObjectHeaders && archive_object->mark().is_expanded() && archive_expand_for_hash(klass, archive_object)) {
188 size = align_object_size(size + 1);
189 }
190 return size;
191 }
192 } else if (Klass::layout_helper_is_array(lh)) {
193 // Array
194 size_t size_in_bytes;
195 size_t array_length = (size_t)archive_array_length(archive_object);
196 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
197 size_in_bytes += (size_t)Klass::layout_helper_header_size(lh);
198
199 size_t size = align_up(size_in_bytes, (size_t)MinObjAlignmentInBytes) / HeapWordSize;
200 if (UseCompactObjectHeaders && archive_object->mark().is_expanded() && archive_expand_for_hash(klass, archive_object)) {
201 size = align_object_size(size + 1);
202 }
203 return size;
204 } else {
205 // Other
206 return ((size_t*)(archive_object))[-1];
207 }
208 }
209
210 oop AOTStreamedHeapLoader::allocate_object(oopDesc* archive_object, markWord mark, size_t size, TRAPS) {
211 assert(!archive_object->is_stackChunk(), "no such objects are archived");
212
213 NoJvmtiEventsMark njem;
214 oop heap_object;
215
216 Klass* klass = archive_object->klass();
217 assert(!(UseCompactObjectHeaders && mark.is_hashed_not_expanded()), "Must not be hashed/not-expanded");
218 if (klass->is_mirror_instance_klass()) {
219 size_t base_size = size;
220 assert(!(UseCompactObjectHeaders && mark.is_not_hashed_expanded()), "should not happen");
221 heap_object = Universe::heap()->class_allocate(klass, size, base_size, CHECK_NULL);
222 } else if (klass->is_instance_klass()) {
223 heap_object = Universe::heap()->obj_allocate(klass, size, CHECK_NULL);
224 } else {
225 assert(klass->is_array_klass(), "must be");
226 int length = archive_array_length(archive_object);
227 bool do_zero = klass->is_objArray_klass();
228 heap_object = Universe::heap()->array_allocate(klass, size, length, do_zero, CHECK_NULL);
229 }
230
231 heap_object->set_mark(mark);
232
233 return heap_object;
234 }
235
236 void AOTStreamedHeapLoader::install_root(int root_index, oop heap_object) {
237 objArrayOop roots = objArrayOop(_roots.resolve());
238 OrderAccess::release(); // Once the store below publishes an object, it can be concurrently picked up by another thread without using the lock
239 roots->obj_at_put(root_index, heap_object);
240 }
241
242 void AOTStreamedHeapLoader::TracingObjectLoader::wait_for_iterator() {
243 if (JavaThread::current()->is_active_Java_thread()) {
244 // When the main thread has bootstrapped past the point of allowing safepoints,
245 // we can and indeed have to use safepoint checking waiting.
246 AOTHeapLoading_lock->wait();
247 } else {
248 // If we have no bootstrapped the main thread far enough, then we cannot and
249 // indeed also don't need to perform safepoint checking waiting.
250 AOTHeapLoading_lock->wait_without_safepoint_check();
251 }
252 }
253
254 // Link object after copying in-place
255 template <typename LinkerT>
256 class AOTStreamedHeapLoader::InPlaceLinkingOopClosure : public BasicOopIterateClosure {
257 private:
258 oop _obj;
259 LinkerT _linker;
260
261 public:
262 InPlaceLinkingOopClosure(oop obj, LinkerT linker)
263 : _obj(obj),
264 _linker(linker) {
265 }
266
267 virtual void do_oop(oop* p) { do_oop_work(p, (int)*(intptr_t*)p); }
268 virtual void do_oop(narrowOop* p) { do_oop_work(p, *(int*)p); }
269
270 template <typename T>
271 void do_oop_work(T* p, int object_index) {
272 int p_offset = pointer_delta_as_int((address)p, cast_from_oop<address>(_obj));
273 oop pointee = _linker(p_offset, object_index);
274 if (pointee != nullptr) {
275 _obj->obj_field_put_access<IS_DEST_UNINITIALIZED>((int)p_offset, pointee);
276 }
277 }
278 };
279
280 template <bool use_coops, typename LinkerT>
281 void AOTStreamedHeapLoader::copy_payload_carefully(oopDesc* archive_object,
282 oop heap_object,
283 BitMap::idx_t header_bit,
284 BitMap::idx_t start_bit,
285 BitMap::idx_t end_bit,
286 LinkerT linker) {
287 using RawElementT = std::conditional_t<use_coops, int32_t, int64_t>;
288 using OopElementT = std::conditional_t<use_coops, narrowOop, oop>;
289
290 BitMap::idx_t unfinished_bit = start_bit;
291 BitMap::idx_t next_reference_bit = _oopmap.find_first_set_bit(unfinished_bit, end_bit);
292
293 // Fill in heap object bytes
294 while (unfinished_bit < end_bit) {
295 assert(unfinished_bit >= start_bit && unfinished_bit < end_bit, "out of bounds copying");
296
297 // This is the address of the pointee inside the input stream
298 size_t payload_offset = unfinished_bit - header_bit;
299 RawElementT* archive_payload_addr = ((RawElementT*)archive_object) + payload_offset;
300 RawElementT* heap_payload_addr = cast_from_oop<RawElementT*>(heap_object) + payload_offset;
301
302 assert(heap_payload_addr >= cast_from_oop<RawElementT*>(heap_object) &&
303 (HeapWord*)heap_payload_addr < cast_from_oop<HeapWord*>(heap_object) + heap_object->size(),
304 "Out of bounds copying");
305
306 if (next_reference_bit > unfinished_bit) {
307 // Primitive bytes available
308 size_t primitive_elements = next_reference_bit - unfinished_bit;
309 size_t primitive_bytes = primitive_elements * sizeof(RawElementT);
310 ::memcpy(heap_payload_addr, archive_payload_addr, primitive_bytes);
311
312 unfinished_bit = next_reference_bit;
313 } else {
314 // Encountered reference
315 RawElementT* archive_p = (RawElementT*)archive_payload_addr;
316 OopElementT* heap_p = (OopElementT*)heap_payload_addr;
317 int pointee_object_index = (int)*archive_p;
318 int heap_p_offset = pointer_delta_as_int((address)heap_p, cast_from_oop<address>(heap_object));
319
320 // The object index is retrieved from the archive, not the heap object. This is
321 // important after GC is enabled. Concurrent GC threads may scan references in the
322 // heap for various reasons after this point. Therefore, it is not okay to first copy
323 // the object index from a reference location in the archived object payload to a
324 // corresponding location in the heap object payload, and then fix it up afterwards to
325 // refer to a heap object. This is why this code iterates carefully over object references
326 // in the archived object, linking them one by one, without clobbering the reference
327 // locations in the heap objects with anything other than transitions from null to the
328 // intended linked object.
329 oop obj = linker(heap_p_offset, pointee_object_index);
330 if (obj != nullptr) {
331 heap_object->obj_field_put(heap_p_offset, obj);
332 }
333
334 unfinished_bit++;
335 next_reference_bit = _oopmap.find_first_set_bit(unfinished_bit, end_bit);
336 }
337 }
338 }
339
340 template <bool use_coops, typename LinkerT>
341 void AOTStreamedHeapLoader::copy_object_impl(oopDesc* archive_object,
342 oop heap_object,
343 size_t size,
344 LinkerT linker) {
345 if (!_allow_gc) {
346 // Without concurrent GC running, we can copy incorrect object references
347 // and metadata references into the heap object and then fix them up in-place.
348 size_t offset = 1;
349 size_t payload_size = size - offset;
350 HeapWord* archive_start = ((HeapWord*)archive_object);
351 HeapWord* heap_start = cast_from_oop<HeapWord*>(heap_object);
352
353 Copy::disjoint_words(archive_start + offset, heap_start + offset, payload_size);
354
355 if (UseCompactObjectHeaders) {
356 // The copying might have missed the first 4 bytes of payload/arraylength, copy that also.
357 *(reinterpret_cast<jint*>(heap_start) + 1) = *(reinterpret_cast<jint*>(archive_start) + 1);
358 }
359
360 // In-place linking fixes up object indices from references of the heap object,
361 // and patches them up to refer to objects. This can be done because we just copied
362 // the payload of the object from the archive to the heap object, including the
363 // reference object indices. However, this is only okay to do before the GC can run.
364 // A concurrent GC thread might racingly read the object payload after GC is enabled.
365 InPlaceLinkingOopClosure cl(heap_object, linker);
366 heap_object->oop_iterate(&cl);
367 HeapShared::remap_loaded_metadata(heap_object);
368 return;
369 }
370
371 // When a concurrent GC may be running, we take care not to copy incorrect oops,
372 // narrowOops or Metadata* into the heap objects. Transitions go from 0 to the
373 // intended runtime linked values only.
374 size_t word_scale = use_coops ? 2 : 1;
375 using RawElementT = std::conditional_t<use_coops, int32_t, int64_t>;
376
377 // Skip the markWord; it is set at allocation time
378 size_t header_size = (UseCompactObjectHeaders && use_coops) ? 1 : word_scale;
379
380 size_t buffer_offset = buffer_offset_for_archive_object(archive_object);
381 const BitMap::idx_t header_bit = obj_bit_idx_for_buffer_offset<use_coops>(buffer_offset);
382 const BitMap::idx_t start_bit = header_bit + header_size;
383 const BitMap::idx_t end_bit = header_bit + size * word_scale;
384
385 BitMap::idx_t curr_bit = start_bit;
386
387 if (UseCompactObjectHeaders && !use_coops) {
388 // Copy first 4 primitive bytes.
389 jint* archive_start = reinterpret_cast<jint*>(archive_object);
390 HeapWord* heap_start = cast_from_oop<HeapWord*>(heap_object);
391 *(reinterpret_cast<jint*>(heap_start) + 1) = *(archive_start + 1);
392 }
393
394 // We are a bit paranoid about GC or other safepointing operations observing
395 // shady metadata fields from the archive that do not point at real metadata.
396 // We deal with this by explicitly reading the requested address from the
397 // archive and fixing it to real Metadata before writing it into the heap object.
398 HeapShared::do_metadata_offsets(heap_object, [&](int metadata_offset) {
399 BitMap::idx_t metadata_field_idx = header_bit + (size_t)metadata_offset / sizeof(RawElementT);
400 BitMap::idx_t skip = word_scale;
401 assert(metadata_field_idx >= start_bit && metadata_field_idx + skip <= end_bit,
402 "Metadata field out of bounds");
403
404 // Copy payload before metadata field
405 copy_payload_carefully<use_coops>(archive_object,
406 heap_object,
407 header_bit,
408 curr_bit,
409 metadata_field_idx,
410 linker);
411
412 // Copy metadata field
413 Metadata* const archive_metadata = *(Metadata**)(uintptr_t(archive_object) + (size_t)metadata_offset);
414 Metadata* const runtime_metadata = archive_metadata != nullptr
415 ? (Metadata*)(address(archive_metadata) + AOTMetaspace::relocation_delta())
416 : nullptr;
417 assert(runtime_metadata == nullptr || AOTMetaspace::in_aot_cache(runtime_metadata), "Invalid metadata pointer");
418 DEBUG_ONLY(Metadata* const previous_metadata = heap_object->metadata_field(metadata_offset);)
419 assert(previous_metadata == nullptr || previous_metadata == runtime_metadata, "Should not observe transient values");
420 heap_object->metadata_field_put(metadata_offset, runtime_metadata);
421 curr_bit = metadata_field_idx + skip;
422 });
423
424 // Copy trailing metadata after the last metadata word. This is usually doing
425 // all the copying.
426 copy_payload_carefully<use_coops>(archive_object,
427 heap_object,
428 header_bit,
429 curr_bit,
430 end_bit,
431 linker);
432 }
433
434 void AOTStreamedHeapLoader::copy_object_eager_linking(oopDesc* archive_object, oop heap_object, size_t size) {
435 auto linker = [&](int p_offset, int pointee_object_index) {
436 oop obj = AOTStreamedHeapLoader::heap_object_for_object_index(pointee_object_index);
437 assert(pointee_object_index == 0 || obj != nullptr, "Eager object loading should only encounter already allocated links");
438 return obj;
439 };
440 if (UseCompressedOops) {
441 copy_object_impl<true>(archive_object, heap_object, size, linker);
442 } else {
443 copy_object_impl<false>(archive_object, heap_object, size, linker);
444 }
445 }
446
447 void AOTStreamedHeapLoader::TracingObjectLoader::copy_object_lazy_linking(int object_index,
448 oopDesc* archive_object,
449 oop heap_object,
450 size_t size,
451 Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack) {
452 auto linker = [&](int p_offset, int pointee_object_index) {
453 dfs_stack.push({pointee_object_index, object_index, p_offset});
454
455 // The tracing linker is a bit lazy and mutates the reference fields in its traversal.
456 // Returning null means don't link now.
457 return oop(nullptr);
458 };
459 if (UseCompressedOops) {
460 copy_object_impl<true>(archive_object, heap_object, size, linker);
461 } else {
462 copy_object_impl<false>(archive_object, heap_object, size, linker);
463 }
464 }
465
466 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_object_inner(int object_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
467 // Allocate object
468 oopDesc* archive_object = archive_object_for_object_index(object_index);
469 size_t size = archive_object_size(archive_object);
470 markWord mark = archive_object->mark();
471
472 // The markWord is marked if the object is a String and it should be interned,
473 // make sure to unmark it before allocating memory for the object.
474 bool string_intern = mark.is_marked();
475 mark = mark.set_unmarked();
476
477 oop heap_object;
478
479 if (string_intern) {
480 int value_object_index = archived_string_value_object_index(archive_object);
481
482 // Materialize the value object.
483 (void)materialize_object(value_object_index, dfs_stack, CHECK_NULL);
484
485 // Allocate and link the string.
486 heap_object = allocate_object(archive_object, mark, size, CHECK_NULL);
487 copy_object_eager_linking(archive_object, heap_object, size);
488
489 assert(java_lang_String::value(heap_object) == heap_object_for_object_index(value_object_index), "Linker should have linked this correctly");
490
491 // Replace the string with interned string
492 heap_object = StringTable::intern(heap_object, CHECK_NULL);
493 } else {
494 heap_object = allocate_object(archive_object, mark, size, CHECK_NULL);
495
496 // Fill in object contents
497 copy_object_lazy_linking(object_index, archive_object, heap_object, size, dfs_stack);
498 }
499
500 // Install forwarding
501 set_heap_object_for_object_index(object_index, heap_object);
502
503 return heap_object;
504 }
505
506 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_object(int object_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
507 if (object_index <= _previous_batch_last_object_index) {
508 // The transitive closure of this object has been materialized; no need to do anything
509 return heap_object_for_object_index(object_index);
510 }
511
512 if (object_index <= _current_batch_last_object_index) {
513 // The AOTThread is currently materializing this object and its transitive closure; only need to wait for it to complete
514 _waiting_for_iterator = true;
515 while (object_index > _previous_batch_last_object_index) {
516 wait_for_iterator();
517 }
518 _waiting_for_iterator = false;
519
520 // Notify the AOT thread if it is waiting for tracing to finish
521 AOTHeapLoading_lock->notify_all();
522 return heap_object_for_object_index(object_index);;
523 }
524
525 oop heap_object = heap_object_for_object_index(object_index);
526 if (heap_object != nullptr) {
527 // Already materialized by mutator
528 return heap_object;
529 }
530
531 return materialize_object_inner(object_index, dfs_stack, THREAD);
532 }
533
534 void AOTStreamedHeapLoader::TracingObjectLoader::drain_stack(Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
535 while (!dfs_stack.is_empty()) {
536 AOTHeapTraversalEntry entry = dfs_stack.pop();
537 int pointee_object_index = entry._pointee_object_index;
538 oop pointee_heap_object = materialize_object(pointee_object_index, dfs_stack, CHECK);
539 oop heap_object = heap_object_for_object_index(entry._base_object_index);
540 if (_allow_gc) {
541 heap_object->obj_field_put(entry._heap_field_offset_bytes, pointee_heap_object);
542 } else {
543 heap_object->obj_field_put_access<IS_DEST_UNINITIALIZED>(entry._heap_field_offset_bytes, pointee_heap_object);
544 }
545 }
546 }
547
548 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_object_transitive(int object_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
549 assert_locked_or_safepoint(AOTHeapLoading_lock);
550 while (_waiting_for_iterator) {
551 wait_for_iterator();
552 }
553
554 auto handlized_materialize_object = [&](TRAPS) {
555 oop obj = materialize_object(object_index, dfs_stack, CHECK_(Handle()));
556 return Handle(THREAD, obj);
557 };
558
559 Handle result = handlized_materialize_object(CHECK_NULL);
560 drain_stack(dfs_stack, CHECK_NULL);
561
562 return result();
563 }
564
565 oop AOTStreamedHeapLoader::TracingObjectLoader::materialize_root(int root_index, Stack<AOTHeapTraversalEntry, mtClassShared>& dfs_stack, TRAPS) {
566 int root_object_index = object_index_for_root_index(root_index);
567 oop root = materialize_object_transitive(root_object_index, dfs_stack, CHECK_NULL);
568 install_root(root_index, root);
569
570 return root;
571 }
572
573 int oop_handle_cmp(const void* left, const void* right) {
574 oop* left_handle = *(oop**)left;
575 oop* right_handle = *(oop**)right;
576
577 if (right_handle > left_handle) {
578 return -1;
579 } else if (left_handle > right_handle) {
580 return 1;
581 }
582
583 return 0;
584 }
585
586 // The range is inclusive
587 void AOTStreamedHeapLoader::IterativeObjectLoader::initialize_range(int first_object_index, int last_object_index, TRAPS) {
588 for (int i = first_object_index; i <= last_object_index; ++i) {
589 oopDesc* archive_object = archive_object_for_object_index(i);
590 markWord mark = archive_object->mark();
591 bool string_intern = mark.is_marked();
592 if (string_intern) {
593 int value_object_index = archived_string_value_object_index(archive_object);
594 if (value_object_index == i + 1) {
595 // Interned strings are eagerly materialized in the allocation phase, so there is
596 // nothing else to do for interned strings here for the string nor its value array.
597 i++;
598 }
599 continue;
600 }
601 size_t size = archive_object_size(archive_object);
602 oop heap_object = heap_object_for_object_index(i);
603 copy_object_eager_linking(archive_object, heap_object, size);
604 }
605 }
606
607 // The range is inclusive
608 size_t AOTStreamedHeapLoader::IterativeObjectLoader::materialize_range(int first_object_index, int last_object_index, TRAPS) {
609 GrowableArrayCHeap<int, mtClassShared> lazy_object_indices(0);
610 size_t materialized_words = 0;
611
612 for (int i = first_object_index; i <= last_object_index; ++i) {
613 oopDesc* archive_object = archive_object_for_object_index(i);
614 markWord mark = archive_object->mark();
615
616 // The markWord is marked if the object is a String and it should be interned,
617 // make sure to unmark it before allocating memory for the object.
618 bool string_intern = mark.is_marked();
619 mark = mark.set_unmarked();
620
621 size_t size = archive_object_size(archive_object);
622 materialized_words += size;
623
624 oop heap_object = heap_object_for_object_index(i);
625 if (heap_object != nullptr) {
626 // Lazy loading has already initialized the object; we must not mutate it
627 lazy_object_indices.append(i);
628 continue;
629 }
630
631 if (!string_intern) {
632 // The normal case; no lazy loading have loaded the object yet
633 heap_object = allocate_object(archive_object, mark, size, CHECK_0);
634 set_heap_object_for_object_index(i, heap_object);
635 continue;
636 }
637
638 // Eagerly materialize interned strings to ensure that objects earlier than the string
639 // in a batch get linked to the intended interned string, and not a copy.
640 int value_object_index = archived_string_value_object_index(archive_object);
641
642 bool is_normal_interned_string = value_object_index == i + 1;
643
644 if (value_object_index < first_object_index) {
645 // If materialized in a previous batch, the value should already be allocated and initialized.
646 assert(heap_object_for_object_index(value_object_index) != nullptr, "should be materialized");
647 } else {
648 // Materialize the value object.
649 oopDesc* archive_value_object = archive_object_for_object_index(value_object_index);
650 markWord value_mark = archive_value_object->mark();
651 size_t value_size = archive_object_size(archive_value_object);
652 oop value_heap_object;
653
654 if (is_normal_interned_string) {
655 // The common case: the value is next to the string. This happens when only the interned
656 // string points to its value character array.
657 assert(value_object_index <= last_object_index, "Must be within this batch: %d <= %d", value_object_index, last_object_index);
658 value_heap_object = allocate_object(archive_value_object, value_mark, value_size, CHECK_0);
659 set_heap_object_for_object_index(value_object_index, value_heap_object);
660 materialized_words += value_size;
661 } else {
662 // In the uncommon case, multiple strings point to the value of an interned string.
663 // The string can then be earlier in the batch.
664 assert(value_object_index < i, "surprising index");
665 value_heap_object = heap_object_for_object_index(value_object_index);
666 }
667
668 copy_object_eager_linking(archive_value_object, value_heap_object, value_size);
669 }
670 // Allocate and link the string.
671 heap_object = allocate_object(archive_object, mark, size, CHECK_0);
672 copy_object_eager_linking(archive_object, heap_object, size);
673
674 assert(java_lang_String::value(heap_object) == heap_object_for_object_index(value_object_index), "Linker should have linked this correctly");
675
676 // Replace the string with interned string
677 heap_object = StringTable::intern(heap_object, CHECK_0);
678 set_heap_object_for_object_index(i, heap_object);
679
680 if (is_normal_interned_string) {
681 // Skip over the string value, already materialized
682 i++;
683 }
684 }
685
686 if (lazy_object_indices.is_empty()) {
687 // Normal case; no sprinkled lazy objects in the root subgraph
688 initialize_range(first_object_index, last_object_index, CHECK_0);
689 } else {
690 // The user lazy initialized some objects that are already initialized; we have to initialize around them
691 // to make sure they are not mutated.
692 int previous_object_index = first_object_index - 1; // Exclusive start of initialization slice
693 for (int i = 0; i < lazy_object_indices.length(); ++i) {
694 int lazy_object_index = lazy_object_indices.at(i);
695 int slice_start_object_index = previous_object_index;
696 int slice_end_object_index = lazy_object_index;
697
698 if (slice_end_object_index - slice_start_object_index > 1) { // Both markers are exclusive
699 initialize_range(slice_start_object_index + 1, slice_end_object_index - 1, CHECK_0);
700 }
701 previous_object_index = lazy_object_index;
702 }
703 // Process tail range
704 if (last_object_index - previous_object_index > 0) {
705 initialize_range(previous_object_index + 1, last_object_index, CHECK_0);
706 }
707 }
708
709 return materialized_words;
710 }
711
712 bool AOTStreamedHeapLoader::IterativeObjectLoader::has_more() {
713 return _current_root_index < _num_roots;
714 }
715
716 void AOTStreamedHeapLoader::IterativeObjectLoader::materialize_next_batch(TRAPS) {
717 assert(has_more(), "only materialize if there is something to materialize");
718
719 int min_batch_objects = 128;
720 int from_root_index = _current_root_index;
721 int max_to_root_index = _num_roots - 1;
722 int until_root_index = from_root_index;
723 int highest_object_index;
724
725 // Expand the batch size from one root, to N roots until we cross 128 objects in total
726 for (;;) {
727 highest_object_index = highest_object_index_for_root_index(until_root_index);
728 if (highest_object_index - _previous_batch_last_object_index >= min_batch_objects) {
729 break;
730 }
731 if (until_root_index == max_to_root_index) {
732 break;
733 }
734 until_root_index++;
735 }
736
737 oop root = nullptr;
738
739 // Materialize objects of necessary, representing the transitive closure of the root
740 if (highest_object_index > _previous_batch_last_object_index) {
741 while (_swapping_root_format) {
742 // When the roots are being upgraded to use handles, it is not safe to racingly
743 // iterate over the object; we must wait. Setting the current batch last object index
744 // to something other than the previous batch last object index indicates to the
745 // root swapping that there is current iteration ongoing.
746 AOTHeapLoading_lock->wait();
747 }
748 int first_object_index = _previous_batch_last_object_index + 1;
749 _current_batch_last_object_index = highest_object_index;
750 size_t allocated_words;
751 {
752 MutexUnlocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
753 allocated_words = materialize_range(first_object_index, highest_object_index, CHECK);
754 }
755 _allocated_words += allocated_words;
756 _previous_batch_last_object_index = _current_batch_last_object_index;
757 if (_waiting_for_iterator) {
758 // If tracer is waiting, let it know at the next point of unlocking that the root
759 // set it waited for has been processed now.
760 AOTHeapLoading_lock->notify_all();
761 }
762 }
763
764 // Install the root
765 for (int i = from_root_index; i <= until_root_index; ++i) {
766 int root_object_index = object_index_for_root_index(i);
767 root = heap_object_for_object_index(root_object_index);
768 install_root(i, root);
769 ++_current_root_index;
770 }
771 }
772
773 bool AOTStreamedHeapLoader::materialize_early(TRAPS) {
774 Ticks start = Ticks::now();
775
776 // Only help with early materialization from the AOT thread if the heap archive can be allocated
777 // without the need for a GC. Otherwise, do lazy loading until GC is enabled later in the bootstrapping.
778 size_t bootstrap_max_memory = Universe::heap()->bootstrap_max_memory();
779 size_t bootstrap_min_memory = MAX2(_heap_region_used, 2 * M);
780
781 size_t before_gc_materialize_budget_bytes = (bootstrap_max_memory > bootstrap_min_memory) ? bootstrap_max_memory - bootstrap_min_memory : 0;
782 size_t before_gc_materialize_budget_words = before_gc_materialize_budget_bytes / HeapWordSize;
783
784 log_info(aot, heap)("Max bootstrapping memory: %zuM, min bootstrapping memory: %zuM, selected budget: %zuM",
785 bootstrap_max_memory / M, bootstrap_min_memory / M, before_gc_materialize_budget_bytes / M);
786
787 while (IterativeObjectLoader::has_more()) {
788 if (_allow_gc || _allocated_words > before_gc_materialize_budget_words) {
789 log_info(aot, heap)("Early object materialization interrupted at root %d", _current_root_index);
790 break;
791 }
792
793 IterativeObjectLoader::materialize_next_batch(CHECK_false);
794 }
795
796 _early_materialization_time_ns = (Ticks::now() - start).nanoseconds();
797
798 bool finished_before_gc_allowed = !_allow_gc && !IterativeObjectLoader::has_more();
799
800 return finished_before_gc_allowed;
801 }
802
803 void AOTStreamedHeapLoader::materialize_late(TRAPS) {
804 Ticks start = Ticks::now();
805
806 // Continue materializing with GC allowed
807
808 while (IterativeObjectLoader::has_more()) {
809 IterativeObjectLoader::materialize_next_batch(CHECK);
810 }
811
812 _late_materialization_time_ns = (Ticks::now() - start).nanoseconds();
813 }
814
815 void AOTStreamedHeapLoader::cleanup() {
816 // First ensure there is no concurrent tracing going on
817 while (_waiting_for_iterator) {
818 AOTHeapLoading_lock->wait();
819 }
820
821 Ticks start = Ticks::now();
822
823 // Remove OopStorage roots
824 if (_objects_are_handles) {
825 size_t num_handles = _num_archived_objects;
826 // Skip the null entry
827 oop** handles = ((oop**)_object_index_to_heap_object_table) + 1;
828 // Sort the handles so that oop storage can release them faster
829 qsort(handles, num_handles, sizeof(oop*), (int (*)(const void*, const void*))oop_handle_cmp);
830 size_t num_null_handles = 0;
831 for (size_t handles_remaining = num_handles; handles_remaining != 0; --handles_remaining) {
832 oop* handle = handles[handles_remaining - 1];
833 if (handle == nullptr) {
834 num_null_handles = handles_remaining;
835 break;
836 }
837 NativeAccess<>::oop_store(handle, nullptr);
838 }
839 Universe::vm_global()->release(&handles[num_null_handles], num_handles - num_null_handles);
840 }
841
842 FREE_C_HEAP_ARRAY(_object_index_to_heap_object_table);
843
844 // Unmap regions
845 FileMapInfo::current_info()->unmap_region(AOTMetaspace::hp);
846 FileMapInfo::current_info()->unmap_region(AOTMetaspace::bm);
847
848 _cleanup_materialization_time_ns = (Ticks::now() - start).nanoseconds();
849
850 log_statistics();
851 }
852
853 void AOTStreamedHeapLoader::log_statistics() {
854 uint64_t total_duration_us = (Ticks::now() - _materialization_start_ticks).microseconds();
855 const bool is_async = _loading_all_objects && !AOTEagerlyLoadObjects;
856 const char* const async_or_sync = is_async ? "async" : "sync";
857 log_info(aot, heap)("start to finish materialization time: " UINT64_FORMAT "us",
858 total_duration_us);
859 log_info(aot, heap)("early object materialization time (%s): " UINT64_FORMAT "us",
860 async_or_sync, _early_materialization_time_ns / 1000);
861 log_info(aot, heap)("late object materialization time (%s): " UINT64_FORMAT "us",
862 async_or_sync, _late_materialization_time_ns / 1000);
863 log_info(aot, heap)("object materialization cleanup time (%s): " UINT64_FORMAT "us",
864 async_or_sync, _cleanup_materialization_time_ns / 1000);
865 log_info(aot, heap)("final object materialization time stall (sync): " UINT64_FORMAT "us",
866 _final_materialization_time_ns / 1000);
867 log_info(aot, heap)("bootstrapping lazy materialization time (sync): " UINT64_FORMAT "us",
868 _accumulated_lazy_materialization_time_ns / 1000);
869
870 uint64_t sync_time = _final_materialization_time_ns + _accumulated_lazy_materialization_time_ns;
871 uint64_t async_time = _early_materialization_time_ns + _late_materialization_time_ns + _cleanup_materialization_time_ns;
872
873 if (!is_async) {
874 sync_time += async_time;
875 async_time = 0;
876 }
877
878 log_info(aot, heap)("sync materialization time: " UINT64_FORMAT "us",
879 sync_time / 1000);
880
881 log_info(aot, heap)("async materialization time: " UINT64_FORMAT "us",
882 async_time / 1000);
883
884 uint64_t iterative_time = (uint64_t)(is_async ? async_time : sync_time);
885 uint64_t materialized_bytes = _allocated_words * HeapWordSize;
886 log_info(aot, heap)("%s materialized " UINT64_FORMAT "K (" UINT64_FORMAT "M/s)", async_or_sync,
887 materialized_bytes / 1024, uint64_t(materialized_bytes * UCONST64(1'000'000'000) / M / iterative_time));
888 }
889
890 void AOTStreamedHeapLoader::materialize_objects() {
891 // We cannot handle any exception when materializing roots. Exits the VM.
892 EXCEPTION_MARK
893
894 // Objects are laid out in DFS order; DFS traverse the roots by linearly walking all objects
895 HandleMark hm(THREAD);
896
897 // Early materialization with a budget before GC is allowed
898 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
899
900 materialize_early(CHECK);
901 await_gc_enabled();
902 materialize_late(CHECK);
903 // Notify materialization is done
904 AOTHeapLoading_lock->notify_all();
905 cleanup();
906 }
907
908 void AOTStreamedHeapLoader::switch_object_index_to_handle(int object_index) {
909 oop heap_object = cast_to_oop(_object_index_to_heap_object_table[object_index]);
910 if (heap_object == nullptr) {
911 return;
912 }
913
914 oop* handle = Universe::vm_global()->allocate();
915 NativeAccess<>::oop_store(handle, heap_object);
916 _object_index_to_heap_object_table[object_index] = handle;
917 }
918
919 void AOTStreamedHeapLoader::enable_gc() {
920 if (AOTEagerlyLoadObjects && !IterativeObjectLoader::has_more()) {
921 // Everything was loaded eagerly at early startup
922 return;
923 }
924
925 // We cannot handle any exception when materializing roots. Exits the VM.
926 EXCEPTION_MARK
927
928 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
929
930 // First wait until no tracing is active
931 while (_waiting_for_iterator) {
932 AOTHeapLoading_lock->wait();
933 }
934
935 // Lock further tracing from starting
936 _waiting_for_iterator = true;
937
938 // Record iterator progress
939 int num_handles = (int)_num_archived_objects;
940
941 // Lock further iteration from starting
942 _swapping_root_format = true;
943
944 // Then wait for the iterator to stop
945 while (_previous_batch_last_object_index != _current_batch_last_object_index) {
946 AOTHeapLoading_lock->wait();
947 }
948
949 if (IterativeObjectLoader::has_more()) {
950 // If there is more to be materialized, we have to upgrade the object index
951 // to object mapping to use handles. If there isn't more to materialize, the
952 // handle will no longer e used; they are only used to materialize objects.
953
954 for (int i = 1; i <= num_handles; ++i) {
955 // Upgrade the roots to use handles
956 switch_object_index_to_handle(i);
957 }
958
959 // From now on, accessing the object table must be done through a handle.
960 _objects_are_handles = true;
961 }
962
963 // Unlock tracing
964 _waiting_for_iterator = false;
965
966 // Unlock iteration
967 _swapping_root_format = false;
968
969 _allow_gc = true;
970
971 AOTHeapLoading_lock->notify_all();
972
973 if (AOTEagerlyLoadObjects && IterativeObjectLoader::has_more()) {
974 materialize_late(CHECK);
975 cleanup();
976 }
977 }
978
979 void AOTStreamedHeapLoader::materialize_thread_object() {
980 AOTThread::materialize_thread_object();
981 }
982
983 void AOTStreamedHeapLoader::finish_materialize_objects() {
984 Ticks start = Ticks::now();
985
986 if (_loading_all_objects) {
987 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
988 // Wait for the AOT thread to finish
989 while (IterativeObjectLoader::has_more()) {
990 AOTHeapLoading_lock->wait();
991 }
992 } else {
993 assert(!AOTEagerlyLoadObjects, "sanity");
994 assert(_current_root_index == 0, "sanity");
995 // Without the full module graph we have done only lazy tracing materialization.
996 // Ensure all roots are processed here by triggering root loading on every root.
997 for (int i = 0; i < _num_roots; ++i) {
998 get_root(i);
999 }
1000 cleanup();
1001 }
1002
1003 _final_materialization_time_ns = (Ticks::now() - start).nanoseconds();
1004 }
1005
1006 void account_lazy_materialization_time_ns(uint64_t time, const char* description, int index) {
1007 AtomicAccess::add(&_accumulated_lazy_materialization_time_ns, time);
1008 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);
1009 }
1010
1011 // Initialize an empty array of AOT heap roots; materialize them lazily
1012 void AOTStreamedHeapLoader::initialize() {
1013 EXCEPTION_MARK
1014
1015 _materialization_start_ticks = Ticks::now();
1016
1017 FileMapInfo::current_info()->map_bitmap_region();
1018
1019 _heap_region = FileMapInfo::current_info()->region_at(AOTMetaspace::hp);
1020 _bitmap_region = FileMapInfo::current_info()->region_at(AOTMetaspace::bm);
1021
1022 assert(_heap_region->used() > 0, "empty heap archive?");
1023
1024 _is_in_use = true;
1025
1026 // archived roots are at this offset in the stream.
1027 size_t roots_offset = FileMapInfo::current_info()->streamed_heap()->roots_offset();
1028 size_t forwarding_offset = FileMapInfo::current_info()->streamed_heap()->forwarding_offset();
1029 size_t root_highest_object_index_table_offset = FileMapInfo::current_info()->streamed_heap()->root_highest_object_index_table_offset();
1030 _num_archived_objects = FileMapInfo::current_info()->streamed_heap()->num_archived_objects();
1031
1032 // The first int is the length of the array
1033 _roots_archive = ((int*)(((address)_heap_region->mapped_base()) + roots_offset)) + 1;
1034 _num_roots = _roots_archive[-1];
1035 _heap_region_used = _heap_region->used();
1036
1037 // We can't retire a TLAB until the filler klass is set; set it to the archived object klass.
1038 CollectedHeap::set_filler_object_klass(vmClasses::Object_klass());
1039
1040 objArrayOop roots = oopFactory::new_objectArray(_num_roots, CHECK);
1041 _roots = OopHandle(Universe::vm_global(), roots);
1042
1043 _object_index_to_buffer_offset_table = (size_t*)(((address)_heap_region->mapped_base()) + forwarding_offset);
1044 // We allocate the first entry for "null"
1045 _object_index_to_heap_object_table = NEW_C_HEAP_ARRAY(void*, _num_archived_objects + 1, mtClassShared);
1046 Copy::zero_to_bytes(_object_index_to_heap_object_table, (_num_archived_objects + 1) * sizeof(void*));
1047
1048 _root_highest_object_index_table = (int*)(((address)_heap_region->mapped_base()) + root_highest_object_index_table_offset);
1049
1050 address start = (address)(_bitmap_region->mapped_base()) + _heap_region->oopmap_offset();
1051 _oopmap = BitMapView((BitMap::bm_word_t*)start, _heap_region->oopmap_size_in_bits());
1052
1053
1054 if (FLAG_IS_DEFAULT(AOTEagerlyLoadObjects)) {
1055 // Concurrency will not help much if there are no extra cores available.
1056 FLAG_SET_ERGO(AOTEagerlyLoadObjects, os::initial_active_processor_count() <= 1);
1057 }
1058
1059 // If the full module graph is not available or the JVMTI class file load hook is on, we
1060 // will prune the object graph to not include cached objects in subgraphs that are not intended
1061 // to be loaded.
1062 _loading_all_objects = CDSConfig::is_using_full_module_graph() && !JvmtiExport::should_post_class_file_load_hook();
1063 if (!_loading_all_objects) {
1064 // When not using FMG, fall back to tracing materialization
1065 FLAG_SET_ERGO(AOTEagerlyLoadObjects, false);
1066 return;
1067 }
1068
1069 if (AOTEagerlyLoadObjects) {
1070 // Objects are laid out in DFS order; DFS traverse the roots by linearly walking all objects
1071 HandleMark hm(THREAD);
1072
1073 // Early materialization with a budget before GC is allowed
1074 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
1075
1076 bool finished_before_gc_allowed = materialize_early(CHECK);
1077 if (finished_before_gc_allowed) {
1078 cleanup();
1079 }
1080 } else {
1081 AOTThread::initialize();
1082 }
1083 }
1084
1085 oop AOTStreamedHeapLoader::materialize_root(int root_index) {
1086 Ticks start = Ticks::now();
1087 // We cannot handle any exception when materializing a root. Exits the VM.
1088 EXCEPTION_MARK
1089 Stack<AOTHeapTraversalEntry, mtClassShared> dfs_stack;
1090 HandleMark hm(THREAD);
1091
1092 oop result;
1093 {
1094 MutexLocker ml(AOTHeapLoading_lock, Mutex::_safepoint_check_flag);
1095
1096 oop root = objArrayOop(_roots.resolve())->obj_at(root_index);
1097
1098 if (root != nullptr) {
1099 // The root has already been materialized
1100 result = root;
1101 } else {
1102 // The root has not been materialized, start tracing materialization
1103 result = TracingObjectLoader::materialize_root(root_index, dfs_stack, CHECK_NULL);
1104 }
1105 }
1106
1107 uint64_t duration = (Ticks::now() - start).nanoseconds();
1108
1109 account_lazy_materialization_time_ns(duration, "root", root_index);
1110
1111 return result;
1112 }
1113
1114 oop AOTStreamedHeapLoader::get_root(int index) {
1115 oop result = objArrayOop(_roots.resolve())->obj_at(index);
1116 if (result == nullptr) {
1117 // Materialize root
1118 result = materialize_root(index);
1119 }
1120 if (result == _roots.resolve()) {
1121 // A self-reference to the roots array acts as a sentinel object for null,
1122 // indicating that the root has been cleared.
1123 result = nullptr;
1124 }
1125 // Acquire the root transitive object payload
1126 OrderAccess::acquire();
1127 return result;
1128 }
1129
1130 void AOTStreamedHeapLoader::clear_root(int index) {
1131 // Self-reference to the roots array acts as a sentinel object for null,
1132 // indicating that the root has been cleared.
1133 objArrayOop(_roots.resolve())->obj_at_put(index, _roots.resolve());
1134 }
1135
1136 void AOTStreamedHeapLoader::await_gc_enabled() {
1137 while (!_allow_gc) {
1138 AOTHeapLoading_lock->wait();
1139 }
1140 }
1141
1142 void AOTStreamedHeapLoader::finish_initialization(FileMapInfo* static_mapinfo) {
1143 static_mapinfo->stream_heap_region();
1144 }
1145
1146 AOTMapLogger::OopDataIterator* AOTStreamedHeapLoader::oop_iterator(FileMapInfo* info, address buffer_start, address buffer_end) {
1147 class StreamedLoaderOopIterator : public AOTStreamedHeapOopIterator {
1148 public:
1149 StreamedLoaderOopIterator(address buffer_start,
1150 int num_archived_objects)
1151 : AOTStreamedHeapOopIterator(buffer_start, num_archived_objects) {}
1152
1153 AOTMapLogger::OopData capture(int dfs_index) override {
1154 size_t buffered_offset = buffer_offset_for_object_index(dfs_index);
1155 address buffered_addr = _buffer_start + buffered_offset;
1156 oopDesc* raw_oop = (oopDesc*)buffered_addr;
1157 size_t size = archive_object_size(raw_oop);
1158
1159 intptr_t target_location = (intptr_t)buffered_offset;
1160 uint32_t narrow_location = checked_cast<uint32_t>(dfs_index);
1161 Klass* klass = raw_oop->klass();
1162
1163 address requested_addr = (address)buffered_offset;
1164
1165 return { buffered_addr,
1166 requested_addr,
1167 target_location,
1168 narrow_location,
1169 raw_oop,
1170 klass,
1171 size,
1172 false };
1173 }
1174
1175 GrowableArrayCHeap<AOTMapLogger::OopData, mtClass>* roots() override {
1176 GrowableArrayCHeap<AOTMapLogger::OopData, mtClass>* result = new GrowableArrayCHeap<AOTMapLogger::OopData, mtClass>();
1177
1178 for (int i = 0; i < _num_roots; ++i) {
1179 int object_index = object_index_for_root_index(i);
1180 result->append(capture(object_index));
1181 }
1182
1183 return result;
1184 }
1185 };
1186
1187 assert(_is_in_use, "printing before initializing?");
1188
1189 return new StreamedLoaderOopIterator(buffer_start, (int)info->streamed_heap()->num_archived_objects());
1190 }
1191
1192 #endif // INCLUDE_CDS_JAVA_HEAP