1 /*
2 * Copyright (c) 1997, 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/aotConstantPoolResolver.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/heapShared.inline.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/classLoaderData.hpp"
31 #include "classfile/javaClasses.inline.hpp"
32 #include "classfile/metadataOnStackMark.hpp"
33 #include "classfile/stringTable.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "classfile/vmClasses.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/codeCache.hpp"
39 #include "interpreter/bootstrapInfo.hpp"
40 #include "interpreter/linkResolver.hpp"
41 #include "jvm.h"
42 #include "logging/log.hpp"
43 #include "logging/logStream.hpp"
44 #include "memory/allocation.inline.hpp"
45 #include "memory/metadataFactory.hpp"
46 #include "memory/metaspaceClosure.hpp"
47 #include "memory/oopFactory.hpp"
48 #include "memory/resourceArea.hpp"
49 #include "memory/universe.hpp"
50 #include "oops/array.hpp"
51 #include "oops/constantPool.inline.hpp"
52 #include "oops/cpCache.inline.hpp"
53 #include "oops/fieldStreams.inline.hpp"
54 #include "oops/flatArrayKlass.hpp"
55 #include "oops/instanceKlass.hpp"
56 #include "oops/klass.inline.hpp"
57 #include "oops/objArrayKlass.hpp"
58 #include "oops/objArrayOop.inline.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "oops/refArrayOop.hpp"
61 #include "oops/typeArrayOop.inline.hpp"
62 #include "prims/jvmtiExport.hpp"
63 #include "runtime/atomicAccess.hpp"
64 #include "runtime/fieldDescriptor.inline.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/init.hpp"
67 #include "runtime/javaCalls.hpp"
68 #include "runtime/javaThread.inline.hpp"
69 #include "runtime/perfData.hpp"
70 #include "runtime/signature.hpp"
71 #include "runtime/vframe.inline.hpp"
72 #include "utilities/checkedCast.hpp"
73 #include "utilities/copy.hpp"
74
75 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
76 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
77 int size = ConstantPool::size(length);
78 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
79 }
80
81 void ConstantPool::copy_fields(const ConstantPool* orig) {
82 // Preserve dynamic constant information from the original pool
83 if (orig->has_dynamic_constant()) {
84 set_has_dynamic_constant();
85 }
86
87 set_major_version(orig->major_version());
88 set_minor_version(orig->minor_version());
89
90 set_source_file_name_index(orig->source_file_name_index());
91 set_generic_signature_index(orig->generic_signature_index());
92 }
93
94 #ifdef ASSERT
95
96 // MetaspaceObj allocation invariant is calloc equivalent memory
97 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
98 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
99 assert(tags != nullptr, "invariant");
100 const int length = tags->length();
101 for (int index = 0; index < length; ++index) {
102 if (JVM_CONSTANT_Invalid != tags->at(index)) {
103 return false;
104 }
105 }
106 return true;
107 }
108
109 #endif
110
111 ConstantPool::ConstantPool() {
112 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
113 }
114
115 ConstantPool::ConstantPool(Array<u1>* tags) :
116 _tags(tags),
117 _length(tags->length()) {
118
119 assert(_tags != nullptr, "invariant");
120 assert(tags->length() == _length, "invariant");
121 assert(tag_array_is_zero_initialized(tags), "invariant");
122 assert(0 == flags(), "invariant");
123 assert(0 == version(), "invariant");
124 assert(nullptr == _pool_holder, "invariant");
125 }
126
127 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
128 if (cache() != nullptr) {
129 MetadataFactory::free_metadata(loader_data, cache());
130 set_cache(nullptr);
131 }
132
133 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
134 set_resolved_klasses(nullptr);
135
136 bsm_entries().deallocate_contents(loader_data);
137
138 release_C_heap_structures();
139
140 // free tag array
141 MetadataFactory::free_array<u1>(loader_data, tags());
142 set_tags(nullptr);
143 }
144
145 void ConstantPool::release_C_heap_structures() {
146 // walk constant pool and decrement symbol reference counts
147 unreference_symbols();
148 }
149
150 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
151 log_trace(aot)("Iter(ConstantPool): %p", this);
152
153 it->push(&_tags, MetaspaceClosure::_writable);
154 it->push(&_cache);
155 it->push(&_pool_holder);
156 it->push(&bsm_entries().offsets());
157 it->push(&bsm_entries().bootstrap_methods());
158 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
159
160 for (int i = 0; i < length(); i++) {
161 // The only MSO's embedded in the CP entries are Symbols:
162 // JVM_CONSTANT_String
163 // JVM_CONSTANT_Utf8
164 constantTag ctag = tag_at(i);
165 if (ctag.is_string() || ctag.is_utf8()) {
166 it->push(symbol_at_addr(i));
167 }
168 }
169 }
170
171 objArrayOop ConstantPool::resolved_references() const {
172 return _cache->resolved_references();
173 }
174
175 // Called from outside constant pool resolution where a resolved_reference array
176 // may not be present.
177 objArrayOop ConstantPool::resolved_references_or_null() const {
178 if (_cache == nullptr) {
179 return nullptr;
180 } else {
181 return _cache->resolved_references();
182 }
183 }
184
185 oop ConstantPool::resolved_reference_at(int index) const {
186 oop result = resolved_references()->obj_at(index);
187 assert(oopDesc::is_oop_or_null(result), "Must be oop");
188 return result;
189 }
190
191 // Use a CAS for multithreaded access
192 oop ConstantPool::set_resolved_reference_at(int index, oop new_result) {
193 assert(oopDesc::is_oop_or_null(new_result), "Must be oop");
194 return refArrayOopDesc::cast(resolved_references())->replace_if_null(index, new_result);
195 }
196
197 // Create resolved_references array and mapping array for original cp indexes
198 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
199 // to map it back for resolving and some unlikely miscellaneous uses.
200 // The objects created by invokedynamic are appended to this list.
201 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
202 const intStack& reference_map,
203 int constant_pool_map_length,
204 TRAPS) {
205 // Initialized the resolved object cache.
206 int map_length = reference_map.length();
207 if (map_length > 0) {
208 // Only need mapping back to constant pool entries. The map isn't used for
209 // invokedynamic resolved_reference entries. For invokedynamic entries,
210 // the constant pool cache index has the mapping back to both the constant
211 // pool and to the resolved reference index.
212 if (constant_pool_map_length > 0) {
213 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
214
215 for (int i = 0; i < constant_pool_map_length; i++) {
216 int x = reference_map.at(i);
217 assert(x == (int)(jushort) x, "klass index is too big");
218 om->at_put(i, (jushort)x);
219 }
220 set_reference_map(om);
221 }
222
223 // Create Java array for holding resolved strings, methodHandles,
224 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
225 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
226 HandleMark hm(THREAD);
227 Handle refs_handle (THREAD, stom); // must handleize.
228 set_resolved_references(loader_data->add_handle(refs_handle));
229
230 // Create a "scratch" copy of the resolved references array to archive
231 if (CDSConfig::is_dumping_heap()) {
232 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
233 HeapShared::add_scratch_resolved_references(this, scratch_references);
234 }
235 }
236 }
237
238 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
239 // A ConstantPool can't possibly have 0xffff valid class entries,
240 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
241 // entry for the class's name. So at most we will have 0xfffe class entries.
242 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
243 // UnresolvedKlass entries that are temporarily created during class redefinition.
244 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
245 assert(resolved_klasses() == nullptr, "sanity");
246 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
247 set_resolved_klasses(rk);
248 }
249
250 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
251 int len = length();
252 int num_klasses = 0;
253 for (int i = 1; i <len; i++) {
254 switch (tag_at(i).value()) {
255 case JVM_CONSTANT_ClassIndex:
256 {
257 const int class_index = klass_index_at(i);
258 unresolved_klass_at_put(i, class_index, num_klasses++);
259 }
260 break;
261 #ifndef PRODUCT
262 case JVM_CONSTANT_Class:
263 case JVM_CONSTANT_UnresolvedClass:
264 case JVM_CONSTANT_UnresolvedClassInError:
265 // All of these should have been reverted back to Unresolved before calling
266 // this function.
267 ShouldNotReachHere();
268 #endif
269 }
270 }
271 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
272 }
273
274 // Hidden class support:
275 void ConstantPool::klass_at_put(int class_index, Klass* k) {
276 assert(k != nullptr, "must be valid klass");
277 CPKlassSlot kslot = klass_slot_at(class_index);
278 int resolved_klass_index = kslot.resolved_klass_index();
279 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
280 AtomicAccess::release_store(adr, k);
281
282 // The interpreter assumes when the tag is stored, the klass is resolved
283 // and the Klass* non-null, so we need hardware store ordering here.
284 release_tag_at_put(class_index, JVM_CONSTANT_Class);
285 }
286
287 #if INCLUDE_CDS_JAVA_HEAP
288 template <typename Function>
289 void ConstantPool::iterate_archivable_resolved_references(Function function) {
290 objArrayOop rr = resolved_references();
291 if (rr != nullptr && cache() != nullptr && CDSConfig::is_dumping_method_handles()) {
292 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
293 if (indy_entries != nullptr) {
294 for (int i = 0; i < indy_entries->length(); i++) {
295 ResolvedIndyEntry *rie = indy_entries->adr_at(i);
296 if (rie->is_resolved() && AOTConstantPoolResolver::is_resolution_deterministic(this, rie->constant_pool_index())) {
297 int rr_index = rie->resolved_references_index();
298 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
299 function(rr_index);
300
301 // Save the BSM as well (sometimes the JIT looks up the BSM it for replay)
302 int indy_cp_index = rie->constant_pool_index();
303 int bsm_mh_cp_index = bootstrap_method_ref_index_at(indy_cp_index);
304 int bsm_rr_index = cp_to_object_index(bsm_mh_cp_index);
305 assert(resolved_reference_at(bsm_rr_index) != nullptr, "must exist");
306 function(bsm_rr_index);
307 }
308 }
309 }
310
311 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
312 if (method_entries != nullptr) {
313 for (int i = 0; i < method_entries->length(); i++) {
314 ResolvedMethodEntry* rme = method_entries->adr_at(i);
315 if (rme->is_resolved(Bytecodes::_invokehandle) && rme->has_appendix() &&
316 cache()->can_archive_resolved_method(this, rme)) {
317 int rr_index = rme->resolved_references_index();
318 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
319 function(rr_index);
320 }
321 }
322 }
323 }
324 }
325
326 // Returns the _resolved_reference array after removing unarchivable items from it.
327 // Returns null if this class is not supported, or _resolved_reference doesn't exist.
328 objArrayOop ConstantPool::prepare_resolved_references_for_archiving() {
329 if (_cache == nullptr) {
330 return nullptr; // nothing to do
331 }
332
333 InstanceKlass *ik = pool_holder();
334 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
335 // Archiving resolved references for classes from non-builtin loaders
336 // is not yet supported.
337 return nullptr;
338 }
339
340 objArrayOop rr = resolved_references();
341 if (rr != nullptr) {
342 ResourceMark rm;
343 int rr_len = rr->length();
344 GrowableArray<bool> keep_resolved_refs(rr_len, rr_len, false);
345
346 iterate_archivable_resolved_references([&](int rr_index) {
347 keep_resolved_refs.at_put(rr_index, true);
348 });
349
350 objArrayOop scratch_rr = HeapShared::scratch_resolved_references(this);
351 Array<u2>* ref_map = reference_map();
352 int ref_map_len = ref_map == nullptr ? 0 : ref_map->length();
353 for (int i = 0; i < rr_len; i++) {
354 oop obj = rr->obj_at(i);
355 scratch_rr->obj_at_put(i, nullptr);
356 if (obj != nullptr) {
357 if (i < ref_map_len) {
358 int index = object_to_cp_index(i);
359 if (tag_at(index).is_string()) {
360 assert(java_lang_String::is_instance(obj), "must be");
361 if (!HeapShared::is_string_too_large_to_archive(obj)) {
362 scratch_rr->obj_at_put(i, obj);
363 }
364 continue;
365 }
366 }
367
368 if (keep_resolved_refs.at(i)) {
369 scratch_rr->obj_at_put(i, obj);
370 }
371 }
372 }
373 return scratch_rr;
374 }
375 return rr;
376 }
377 #endif
378
379 #if INCLUDE_CDS
380 // CDS support. Create a new resolved_references array.
381 void ConstantPool::restore_unshareable_info(TRAPS) {
382 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
383 return;
384 }
385 assert(is_constantPool(), "ensure C++ vtable is restored");
386 assert(on_stack(), "should always be set for constant pools in AOT cache");
387 assert(in_aot_cache(), "should always be set for constant pools in AOT cache");
388 if (is_for_method_handle_intrinsic()) {
389 // See the same check in remove_unshareable_info() below.
390 assert(cache() == nullptr, "must not have cpCache");
391 return;
392 }
393 assert(_cache != nullptr, "constant pool _cache should not be null");
394
395 // Only create the new resolved references array if it hasn't been attempted before
396 if (resolved_references() != nullptr) return;
397
398 if (vmClasses::Object_klass_is_loaded()) {
399 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
400 #if INCLUDE_CDS_JAVA_HEAP
401 if (HeapShared::is_archived_heap_in_use() &&
402 _cache->archived_references() != nullptr) {
403 oop archived = _cache->archived_references();
404 // Create handle for the archived resolved reference array object
405 HandleMark hm(THREAD);
406 Handle refs_handle(THREAD, archived);
407 set_resolved_references(loader_data->add_handle(refs_handle));
408 _cache->clear_archived_references();
409 } else
410 #endif
411 {
412 // No mapped archived resolved reference array
413 // Recreate the object array and add to ClassLoaderData.
414 int map_length = resolved_reference_length();
415 if (map_length > 0) {
416 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
417 HandleMark hm(THREAD);
418 Handle refs_handle(THREAD, stom); // must handleize.
419 set_resolved_references(loader_data->add_handle(refs_handle));
420 }
421 }
422 }
423
424 if (CDSConfig::is_dumping_final_static_archive() && CDSConfig::is_dumping_heap() && resolved_references() != nullptr) {
425 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), resolved_references()->length(), CHECK);
426 HeapShared::add_scratch_resolved_references(this, scratch_references);
427 }
428 }
429
430 void ConstantPool::remove_unshareable_info() {
431 // ConstantPools in AOT cache are in the RO region, so the _flags cannot be modified.
432 // The _on_stack flag is used to prevent ConstantPools from deallocation during
433 // class redefinition. Since such ConstantPools cannot be deallocated anyway,
434 // we always set _on_stack to true to avoid having to change _flags during runtime.
435 _flags |= (_on_stack | _in_aot_cache);
436
437 if (is_for_method_handle_intrinsic()) {
438 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
439 // that need to be removed/restored. It has no cpCache since the intrinsic methods
440 // don't have any bytecodes.
441 assert(cache() == nullptr, "must not have cpCache");
442 return;
443 }
444
445 bool update_resolved_reference = true;
446 if (CDSConfig::is_dumping_final_static_archive()) {
447 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
448 InstanceKlass* src_holder = src_cp->pool_holder();
449 if (src_holder->defined_by_other_loaders()) {
450 // Unregistered classes are not loaded in the AOT assembly phase. The resolved reference length
451 // is already saved during the training run.
452 precond(!src_holder->is_loaded());
453 precond(resolved_reference_length() >= 0);
454 precond(resolved_references() == nullptr);
455 update_resolved_reference = false;
456 }
457 }
458
459 // resolved_references(): remember its length. If it cannot be restored
460 // from the archived heap objects at run time, we need to dynamically allocate it.
461 if (update_resolved_reference && cache() != nullptr) {
462 set_resolved_reference_length(
463 resolved_references() != nullptr ? resolved_references()->length() : 0);
464 set_resolved_references(OopHandle());
465 }
466 remove_unshareable_entries();
467 }
468
469 static const char* get_type(Klass* k) {
470 const char* type;
471 Klass* src_k;
472 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
473 src_k = ArchiveBuilder::current()->get_source_addr(k);
474 } else {
475 src_k = k;
476 }
477
478 if (src_k->is_objArray_klass()) {
479 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
480 assert(!src_k->is_objArray_klass(), "sanity");
481 assert(src_k->is_instance_klass() || src_k->is_typeArray_klass(), "Sanity check");
482 }
483
484 if (src_k->is_typeArray_klass()) {
485 type = "prim";
486 } else {
487 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
488 if (src_ik->defined_by_boot_loader()) {
489 return "boot";
490 } else if (src_ik->defined_by_platform_loader()) {
491 return "plat";
492 } else if (src_ik->defined_by_app_loader()) {
493 return "app";
494 } else {
495 return "unreg";
496 }
497 }
498
499 return type;
500 }
501
502 void ConstantPool::remove_unshareable_entries() {
503 ResourceMark rm;
504 log_info(aot, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
505 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
506 int cp_tag = tag_at(cp_index).value();
507 switch (cp_tag) {
508 case JVM_CONSTANT_UnresolvedClass:
509 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, false);
510 break;
511 case JVM_CONSTANT_UnresolvedClassInError:
512 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
513 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, true);
514 break;
515 case JVM_CONSTANT_MethodHandleInError:
516 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
517 break;
518 case JVM_CONSTANT_MethodTypeInError:
519 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
520 break;
521 case JVM_CONSTANT_DynamicInError:
522 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
523 break;
524 case JVM_CONSTANT_Class:
525 remove_resolved_klass_if_non_deterministic(cp_index);
526 break;
527 default:
528 break;
529 }
530 }
531
532 if (cache() != nullptr) {
533 // cache() is null if this class is not yet linked.
534 cache()->remove_unshareable_info();
535 }
536 }
537
538 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
539 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
540 assert(tag_at(cp_index).is_klass(), "must be resolved");
541
542 bool can_archive;
543 Klass* k = nullptr;
544
545 if (CDSConfig::is_dumping_preimage_static_archive()) {
546 can_archive = false;
547 } else {
548 k = resolved_klass_at(cp_index);
549 if (k == nullptr) {
550 // We'd come here if the referenced class has been excluded via
551 // SystemDictionaryShared::is_excluded_class(). As a result, ArchiveBuilder
552 // has cleared the resolved_klasses()->at(...) pointer to null. Thus, we
553 // need to revert the tag to JVM_CONSTANT_UnresolvedClass.
554 can_archive = false;
555 } else {
556 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
557 can_archive = AOTConstantPoolResolver::is_resolution_deterministic(src_cp, cp_index);
558 }
559 }
560
561 if (!can_archive) {
562 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
563 // This might be at a safepoint but do this in the right order.
564 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
565 resolved_klasses()->at_put(resolved_klass_index, nullptr);
566 }
567
568 LogStreamHandle(Trace, aot, resolve) log;
569 if (log.is_enabled()) {
570 ResourceMark rm;
571 log.print("%s klass CP entry [%3d]: %s %s",
572 (can_archive ? "archived" : "reverted"),
573 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
574 if (can_archive) {
575 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
576 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
577 } else {
578 Symbol* name = klass_name_at(cp_index);
579 log.print(" => %s", name->as_C_string());
580 }
581 }
582
583 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(can_archive, /*reverted=*/!can_archive);
584 }
585 #endif // INCLUDE_CDS
586
587 int ConstantPool::cp_to_object_index(int cp_index) {
588 // this is harder don't do this so much.
589 int i = reference_map()->find(checked_cast<u2>(cp_index));
590 // We might not find the index for jsr292 call.
591 return (i < 0) ? _no_index_sentinel : i;
592 }
593
594 void ConstantPool::string_at_put(int obj_index, oop str) {
595 oop result = set_resolved_reference_at(obj_index, str);
596 assert(result == nullptr || result == str, "Only set once or to the same string.");
597 }
598
599 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
600 ResourceMark rm;
601 int line_number = -1;
602 const char * source_file = nullptr;
603 if (JavaThread::current()->has_last_Java_frame()) {
604 // try to identify the method which called this function.
605 vframeStream vfst(JavaThread::current());
606 if (!vfst.at_end()) {
607 line_number = vfst.method()->line_number_from_bci(vfst.bci());
608 Symbol* s = vfst.method()->method_holder()->source_file_name();
609 if (s != nullptr) {
610 source_file = s->as_C_string();
611 }
612 }
613 }
614 if (k != this_cp->pool_holder()) {
615 // only print something if the classes are different
616 if (source_file != nullptr) {
617 log_debug(class, resolve)("%s %s %s:%d",
618 this_cp->pool_holder()->external_name(),
619 k->external_name(), source_file, line_number);
620 } else {
621 log_debug(class, resolve)("%s %s",
622 this_cp->pool_holder()->external_name(),
623 k->external_name());
624 }
625 }
626 }
627
628 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
629 TRAPS) {
630 JavaThread* javaThread = THREAD;
631
632 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
633 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
634 // the entry and tag is not updated atomically.
635 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
636 int resolved_klass_index = kslot.resolved_klass_index();
637 int name_index = kslot.name_index();
638 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
639
640 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
641 // the unresolved_klasses() array.
642 if (this_cp->tag_at(cp_index).is_klass()) {
643 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
644 assert(klass != nullptr, "must be resolved");
645 return klass;
646 }
647
648 // This tag doesn't change back to unresolved class unless at a safepoint.
649 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
650 // The original attempt to resolve this constant pool entry failed so find the
651 // class of the original error and throw another error of the same class
652 // (JVMS 5.4.3).
653 // If there is a detail message, pass that detail message to the error.
654 // The JVMS does not strictly require us to duplicate the same detail message,
655 // or any internal exception fields such as cause or stacktrace. But since the
656 // detail message is often a class name or other literal string, we will repeat it
657 // if we can find it in the symbol table.
658 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
659 ShouldNotReachHere();
660 }
661
662 HandleMark hm(THREAD);
663 Handle mirror_handle;
664 Symbol* name = this_cp->symbol_at(name_index);
665 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
666
667 Klass* k;
668 {
669 // Turn off the single stepping while doing class resolution
670 JvmtiHideSingleStepping jhss(javaThread);
671 k = SystemDictionary::resolve_or_fail(name, loader, true, THREAD);
672 } // JvmtiHideSingleStepping jhss(javaThread);
673
674 if (!HAS_PENDING_EXCEPTION) {
675 // preserve the resolved klass from unloading
676 mirror_handle = Handle(THREAD, k->java_mirror());
677 // Do access check for klasses
678 verify_constant_pool_resolve(this_cp, k, THREAD);
679 }
680
681 #ifdef DEBUG
682 if (!HAS_PENDING_EXCEPTION && k->is_objArray_klass()) {
683 Klass* bottom_klass = ObjArrayKlass::cast(k)->bottom_klass();
684 assert(bottom_klass != nullptr, "Should be set");
685 assert(bottom_klass->is_instance_klass() || bottom_klass->is_typeArray_klass(), "Sanity check");
686 }
687 #endif
688
689 // Failed to resolve class. We must record the errors so that subsequent attempts
690 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
691 if (HAS_PENDING_EXCEPTION) {
692 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
693 // If CHECK_NULL above doesn't return the exception, that means that
694 // some other thread has beaten us and has resolved the class.
695 // To preserve old behavior, we return the resolved class.
696 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
697 assert(klass != nullptr, "must be resolved if exception was cleared");
698 return klass;
699 }
700
701 // logging for class+resolve.
702 if (log_is_enabled(Debug, class, resolve)){
703 trace_class_resolution(this_cp, k);
704 }
705
706 // The interpreter assumes when the tag is stored, the klass is resolved
707 // and the Klass* stored in _resolved_klasses is non-null, so we need
708 // hardware store ordering here.
709 // We also need to CAS to not overwrite an error from a racing thread.
710 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
711 AtomicAccess::release_store(adr, k);
712
713 jbyte old_tag = AtomicAccess::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
714 (jbyte)JVM_CONSTANT_UnresolvedClass,
715 (jbyte)JVM_CONSTANT_Class);
716
717 // We need to recheck exceptions from racing thread and return the same.
718 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
719 // Remove klass.
720 AtomicAccess::store(adr, (Klass*)nullptr);
721 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
722 }
723
724 return k;
725 }
726
727
728 // Does not update ConstantPool* - to avoid any exception throwing. Used
729 // by compiler and exception handling. Also used to avoid classloads for
730 // instanceof operations. Returns null if the class has not been loaded or
731 // if the verification of constant pool failed
732 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
733 CPKlassSlot kslot = this_cp->klass_slot_at(which);
734 int resolved_klass_index = kslot.resolved_klass_index();
735 int name_index = kslot.name_index();
736 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
737
738 if (this_cp->tag_at(which).is_klass()) {
739 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
740 assert(k != nullptr, "must be resolved");
741 return k;
742 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
743 return nullptr;
744 } else {
745 Thread* current = Thread::current();
746 HandleMark hm(current);
747 Symbol* name = this_cp->symbol_at(name_index);
748 oop loader = this_cp->pool_holder()->class_loader();
749 Handle h_loader (current, loader);
750 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader);
751
752 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
753 if (k != nullptr && current->is_Java_thread()) {
754 // Make sure that resolving is legal
755 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
756 ExceptionMark em(THREAD);
757 // return null if verification fails
758 verify_constant_pool_resolve(this_cp, k, THREAD);
759 if (HAS_PENDING_EXCEPTION) {
760 CLEAR_PENDING_EXCEPTION;
761 return nullptr;
762 }
763 return k;
764 } else {
765 return k;
766 }
767 }
768 }
769
770 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
771 int which) {
772 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
773 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
774 // FIXME: should be an assert
775 log_debug(class, resolve)("bad BSM %d in:", which); cpool->print();
776 return nullptr;
777 }
778 return cpool->cache()->method_if_resolved(which);
779 }
780
781
782 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
783 if (cpool->cache() == nullptr) return false; // nothing to load yet
784 if (code == Bytecodes::_invokedynamic) {
785 return cpool->resolved_indy_entry_at(which)->has_appendix();
786 } else {
787 return cpool->resolved_method_entry_at(which)->has_appendix();
788 }
789 }
790
791 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
792 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
793 if (code == Bytecodes::_invokedynamic) {
794 return cpool->resolved_reference_from_indy(which);
795 } else {
796 return cpool->cache()->appendix_if_resolved(which);
797 }
798 }
799
800
801 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
802 if (cpool->cache() == nullptr) return false; // nothing to load yet
803 if (code == Bytecodes::_invokedynamic) {
804 return cpool->resolved_indy_entry_at(which)->has_local_signature();
805 } else {
806 return cpool->resolved_method_entry_at(which)->has_local_signature();
807 }
808 }
809
810 // Translate index, which could be CPCache index or Indy index, to a constant pool index
811 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
812 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
813 switch(code) {
814 case Bytecodes::_invokedynamic:
815 return invokedynamic_bootstrap_ref_index_at(index);
816 case Bytecodes::_getfield:
817 case Bytecodes::_getstatic:
818 case Bytecodes::_putfield:
819 case Bytecodes::_putstatic:
820 return resolved_field_entry_at(index)->constant_pool_index();
821 case Bytecodes::_invokeinterface:
822 case Bytecodes::_invokehandle:
823 case Bytecodes::_invokespecial:
824 case Bytecodes::_invokestatic:
825 case Bytecodes::_invokevirtual:
826 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
827 return resolved_method_entry_at(index)->constant_pool_index();
828 default:
829 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
830 }
831 }
832
833 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
834 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
835 switch(code) {
836 case Bytecodes::_invokedynamic:
837 return resolved_indy_entry_at(index)->is_resolved();
838
839 case Bytecodes::_getfield:
840 case Bytecodes::_getstatic:
841 case Bytecodes::_putfield:
842 case Bytecodes::_putstatic:
843 return resolved_field_entry_at(index)->is_resolved(code);
844
845 case Bytecodes::_invokeinterface:
846 case Bytecodes::_invokehandle:
847 case Bytecodes::_invokespecial:
848 case Bytecodes::_invokestatic:
849 case Bytecodes::_invokevirtual:
850 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
851 return resolved_method_entry_at(index)->is_resolved(code);
852
853 default:
854 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
855 }
856 }
857
858 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
859 if (tag_at(cp_index).has_bootstrap()) {
860 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
861 assert(tag_at(pool_index).is_name_and_type(), "");
862 return pool_index;
863 }
864 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
865 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
866 jint ref_index = *int_at_addr(cp_index);
867 return extract_high_short_from_int(ref_index);
868 }
869
870 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
871 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
872 }
873
874 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
875 // which may be either a Constant Pool index or a rewritten index
876 int pool_index = which;
877 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
878 pool_index = to_cp_index(which, code);
879 return tag_at(pool_index);
880 }
881
882 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
883 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
884 jint ref_index = *int_at_addr(cp_index);
885 return extract_low_short_from_int(ref_index);
886 }
887
888 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
889 assert(code != Bytecodes::_invokedynamic,
890 "an invokedynamic instruction does not have a klass");
891 return uncached_klass_ref_index_at(to_cp_index(index, code));
892 }
893
894 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
895 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
896 return; // short cut, typeArray klass is always accessible
897 }
898 Klass* holder = this_cp->pool_holder();
899 LinkResolver::check_klass_accessibility(holder, k, CHECK);
900 }
901
902
903 u2 ConstantPool::name_ref_index_at(int cp_index) {
904 jint ref_index = name_and_type_at(cp_index);
905 return extract_low_short_from_int(ref_index);
906 }
907
908
909 u2 ConstantPool::signature_ref_index_at(int cp_index) {
910 jint ref_index = name_and_type_at(cp_index);
911 return extract_high_short_from_int(ref_index);
912 }
913
914
915 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
916 return klass_at(klass_ref_index_at(which, code), THREAD);
917 }
918
919 Symbol* ConstantPool::klass_name_at(int cp_index) const {
920 return symbol_at(klass_slot_at(cp_index).name_index());
921 }
922
923 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
924 jint ref_index = klass_ref_index_at(which, code);
925 return klass_at_noresolve(ref_index);
926 }
927
928 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
929 jint ref_index = uncached_klass_ref_index_at(cp_index);
930 return klass_at_noresolve(ref_index);
931 }
932
933 char* ConstantPool::string_at_noresolve(int cp_index) {
934 return unresolved_string_at(cp_index)->as_C_string();
935 }
936
937 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
938 return Signature::basic_type(symbol_at(cp_index));
939 }
940
941
942 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
943 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
944 if (this_cp->tag_at(index).is_string()) {
945 this_cp->string_at(index, CHECK);
946 }
947 }
948 }
949
950 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
951 // Note: caller needs ResourceMark
952
953 // Dig out the detailed message to reuse if possible
954 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
955 if (msg != nullptr) {
956 return msg;
957 }
958
959 Symbol* message = nullptr;
960 // Return specific message for the tag
961 switch (tag.value()) {
962 case JVM_CONSTANT_UnresolvedClass:
963 // return the class name in the error message
964 message = this_cp->klass_name_at(which);
965 break;
966 case JVM_CONSTANT_MethodHandle:
967 // return the method handle name in the error message
968 message = this_cp->method_handle_name_ref_at(which);
969 break;
970 case JVM_CONSTANT_MethodType:
971 // return the method type signature in the error message
972 message = this_cp->method_type_signature_at(which);
973 break;
974 case JVM_CONSTANT_Dynamic:
975 // return the name of the condy in the error message
976 message = this_cp->uncached_name_ref_at(which);
977 break;
978 default:
979 ShouldNotReachHere();
980 }
981
982 return message != nullptr ? message->as_C_string() : nullptr;
983 }
984
985 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
986 constantTag tag, oop pending_exception) {
987
988 ResourceMark rm(current);
989 Symbol* error = pending_exception->klass()->name();
990 oop cause = java_lang_Throwable::cause(pending_exception);
991
992 // Also dig out the exception cause, if present.
993 Symbol* cause_sym = nullptr;
994 const char* cause_msg = nullptr;
995 if (cause != nullptr && cause != pending_exception) {
996 cause_sym = cause->klass()->name();
997 cause_msg = java_lang_Throwable::message_as_utf8(cause);
998 }
999
1000 const char* message = exception_message(this_cp, which, tag, pending_exception);
1001 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1002 }
1003
1004
1005 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1006 ResourceMark rm(THREAD);
1007 const char* message = nullptr;
1008 Symbol* cause = nullptr;
1009 const char* cause_msg = nullptr;
1010 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1011 assert(error != nullptr, "checking");
1012
1013 CLEAR_PENDING_EXCEPTION;
1014 if (message != nullptr) {
1015 if (cause != nullptr) {
1016 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1017 THROW_MSG_CAUSE(error, message, h_cause);
1018 } else {
1019 THROW_MSG(error, message);
1020 }
1021 } else {
1022 if (cause != nullptr) {
1023 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1024 THROW_CAUSE(error, h_cause);
1025 } else {
1026 THROW(error);
1027 }
1028 }
1029 }
1030
1031 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1032 // exception in the resolution error table, so that the same exception is thrown again.
1033 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1034 constantTag tag, TRAPS) {
1035
1036 int error_tag = tag.error_value();
1037
1038 if (!PENDING_EXCEPTION->
1039 is_a(vmClasses::LinkageError_klass())) {
1040 // Just throw the exception and don't prevent these classes from
1041 // being loaded due to virtual machine errors like StackOverflow
1042 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1043 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1044 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1045 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1046 // CAS in the tag. If a thread beat us to registering this error that's fine.
1047 // If another thread resolved the reference, this is a race condition. This
1048 // thread may have had a security manager or something temporary.
1049 // This doesn't deterministically get an error. So why do we save this?
1050 // We save this because jvmti can add classes to the bootclass path after
1051 // this error, so it needs to get the same error if the error is first.
1052 jbyte old_tag = AtomicAccess::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1053 (jbyte)tag.value(),
1054 (jbyte)error_tag);
1055 if (old_tag != error_tag && old_tag != tag.value()) {
1056 // MethodHandles and MethodType doesn't change to resolved version.
1057 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1058 // Forget the exception and use the resolved class.
1059 CLEAR_PENDING_EXCEPTION;
1060 }
1061 } else {
1062 // some other thread put this in error state
1063 throw_resolution_error(this_cp, cp_index, CHECK);
1064 }
1065 }
1066
1067 constantTag ConstantPool::constant_tag_at(int cp_index) {
1068 constantTag tag = tag_at(cp_index);
1069 if (tag.is_dynamic_constant()) {
1070 BasicType bt = basic_type_for_constant_at(cp_index);
1071 return constantTag(constantTag::type2tag(bt));
1072 }
1073 return tag;
1074 }
1075
1076 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1077 constantTag tag = tag_at(cp_index);
1078 if (tag.is_dynamic_constant() ||
1079 tag.is_dynamic_constant_in_error()) {
1080 // have to look at the signature for this one
1081 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1082 return Signature::basic_type(constant_type);
1083 }
1084 return tag.basic_type();
1085 }
1086
1087 // Called to resolve constants in the constant pool and return an oop.
1088 // Some constant pool entries cache their resolved oop. This is also
1089 // called to create oops from constants to use in arguments for invokedynamic
1090 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1091 int cp_index, int cache_index,
1092 bool* status_return, TRAPS) {
1093 oop result_oop = nullptr;
1094
1095 if (cache_index == _possible_index_sentinel) {
1096 // It is possible that this constant is one which is cached in the objects.
1097 // We'll do a linear search. This should be OK because this usage is rare.
1098 // FIXME: If bootstrap specifiers stress this code, consider putting in
1099 // a reverse index. Binary search over a short array should do it.
1100 assert(cp_index > 0, "valid constant pool index");
1101 cache_index = this_cp->cp_to_object_index(cp_index);
1102 }
1103 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1104 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1105
1106 if (cache_index >= 0) {
1107 result_oop = this_cp->resolved_reference_at(cache_index);
1108 if (result_oop != nullptr) {
1109 if (result_oop == Universe::the_null_sentinel()) {
1110 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1111 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1112 result_oop = nullptr;
1113 }
1114 if (status_return != nullptr) (*status_return) = true;
1115 return result_oop;
1116 // That was easy...
1117 }
1118 cp_index = this_cp->object_to_cp_index(cache_index);
1119 }
1120
1121 jvalue prim_value; // temp used only in a few cases below
1122
1123 constantTag tag = this_cp->tag_at(cp_index);
1124
1125 if (status_return != nullptr) {
1126 // don't trigger resolution if the constant might need it
1127 switch (tag.value()) {
1128 case JVM_CONSTANT_Class:
1129 assert(this_cp->resolved_klass_at(cp_index) != nullptr, "must be resolved");
1130 break;
1131 case JVM_CONSTANT_String:
1132 case JVM_CONSTANT_Integer:
1133 case JVM_CONSTANT_Float:
1134 case JVM_CONSTANT_Long:
1135 case JVM_CONSTANT_Double:
1136 // these guys trigger OOM at worst
1137 break;
1138 default:
1139 (*status_return) = false;
1140 return nullptr;
1141 }
1142 // from now on there is either success or an OOME
1143 (*status_return) = true;
1144 }
1145
1146 switch (tag.value()) {
1147
1148 case JVM_CONSTANT_UnresolvedClass:
1149 case JVM_CONSTANT_Class:
1150 {
1151 assert(cache_index == _no_index_sentinel, "should not have been set");
1152 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1153 // ldc wants the java mirror.
1154 result_oop = resolved->java_mirror();
1155 break;
1156 }
1157
1158 case JVM_CONSTANT_Dynamic:
1159 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1160 ClassLoader::perf_resolve_invokedynamic_count());
1161
1162 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1163 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1164
1165 // The initial step in resolving an unresolved symbolic reference to a
1166 // dynamically-computed constant is to resolve the symbolic reference to a
1167 // method handle which will be the bootstrap method for the dynamically-computed
1168 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1169 // method fails, then a MethodHandleInError is stored at the corresponding
1170 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1171 // set a DynamicConstantInError here since any subsequent use of this
1172 // bootstrap method will encounter the resolution of MethodHandleInError.
1173 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1174 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1175 // for the bootstrap_specifier created above.
1176 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1177 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1178 if (HAS_PENDING_EXCEPTION) {
1179 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1180 // will check for a LinkageError and store a DynamicConstantInError.
1181 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1182 }
1183 result_oop = bootstrap_specifier.resolved_value()();
1184 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1185 if (!is_reference_type(type)) {
1186 // Make sure the primitive value is properly boxed.
1187 // This is a JDK responsibility.
1188 const char* fail = nullptr;
1189 if (result_oop == nullptr) {
1190 fail = "null result instead of box";
1191 } else if (!is_java_primitive(type)) {
1192 // FIXME: support value types via unboxing
1193 fail = "can only handle references and primitives";
1194 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1195 fail = "primitive is not properly boxed";
1196 }
1197 if (fail != nullptr) {
1198 // Since this exception is not a LinkageError, throw exception
1199 // but do not save a DynamicInError resolution result.
1200 // See section 5.4.3 of the VM spec.
1201 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1202 }
1203 }
1204
1205 LogTarget(Debug, methodhandles, condy) lt_condy;
1206 if (lt_condy.is_enabled()) {
1207 LogStream ls(lt_condy);
1208 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1209 }
1210 break;
1211 }
1212
1213 case JVM_CONSTANT_String:
1214 assert(cache_index != _no_index_sentinel, "should have been set");
1215 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1216 break;
1217
1218 case JVM_CONSTANT_MethodHandle:
1219 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1220 ClassLoader::perf_resolve_method_handle_count());
1221
1222 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1223 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1224 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1225 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1226 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1227 { ResourceMark rm(THREAD);
1228 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1229 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1230 callee_index, name->as_C_string(), signature->as_C_string());
1231 }
1232
1233 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1234 if (HAS_PENDING_EXCEPTION) {
1235 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1236 }
1237
1238 // Check constant pool method consistency
1239 if ((callee->is_interface() && m_tag.is_method()) ||
1240 (!callee->is_interface() && m_tag.is_interface_method())) {
1241 ResourceMark rm(THREAD);
1242 stringStream ss;
1243 ss.print("Inconsistent constant pool data in classfile for class %s. "
1244 "Method '", callee->name()->as_C_string());
1245 signature->print_as_signature_external_return_type(&ss);
1246 ss.print(" %s(", name->as_C_string());
1247 signature->print_as_signature_external_parameters(&ss);
1248 ss.print(")' at index %d is %s and should be %s",
1249 cp_index,
1250 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1251 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1252 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1253 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1254 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1255 }
1256
1257 Klass* klass = this_cp->pool_holder();
1258 HandleMark hm(THREAD);
1259 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1260 callee, name, signature,
1261 THREAD);
1262 if (HAS_PENDING_EXCEPTION) {
1263 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1264 }
1265 result_oop = value();
1266 break;
1267 }
1268
1269 case JVM_CONSTANT_MethodType:
1270 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1271 ClassLoader::perf_resolve_method_type_count());
1272
1273 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1274 { ResourceMark rm(THREAD);
1275 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1276 cp_index, this_cp->method_type_index_at(cp_index),
1277 signature->as_C_string());
1278 }
1279 Klass* klass = this_cp->pool_holder();
1280 HandleMark hm(THREAD);
1281 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1282 result_oop = value();
1283 if (HAS_PENDING_EXCEPTION) {
1284 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1285 }
1286 break;
1287 }
1288
1289 case JVM_CONSTANT_Integer:
1290 assert(cache_index == _no_index_sentinel, "should not have been set");
1291 prim_value.i = this_cp->int_at(cp_index);
1292 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1293 break;
1294
1295 case JVM_CONSTANT_Float:
1296 assert(cache_index == _no_index_sentinel, "should not have been set");
1297 prim_value.f = this_cp->float_at(cp_index);
1298 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1299 break;
1300
1301 case JVM_CONSTANT_Long:
1302 assert(cache_index == _no_index_sentinel, "should not have been set");
1303 prim_value.j = this_cp->long_at(cp_index);
1304 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1305 break;
1306
1307 case JVM_CONSTANT_Double:
1308 assert(cache_index == _no_index_sentinel, "should not have been set");
1309 prim_value.d = this_cp->double_at(cp_index);
1310 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1311 break;
1312
1313 case JVM_CONSTANT_UnresolvedClassInError:
1314 case JVM_CONSTANT_DynamicInError:
1315 case JVM_CONSTANT_MethodHandleInError:
1316 case JVM_CONSTANT_MethodTypeInError:
1317 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1318 break;
1319
1320 default:
1321 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1322 break;
1323 }
1324
1325 if (cache_index >= 0) {
1326 // Benign race condition: resolved_references may already be filled in.
1327 // The important thing here is that all threads pick up the same result.
1328 // It doesn't matter which racing thread wins, as long as only one
1329 // result is used by all threads, and all future queries.
1330 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1331 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1332 if (old_result == nullptr) {
1333 return result_oop; // was installed
1334 } else {
1335 // Return the winning thread's result. This can be different than
1336 // the result here for MethodHandles.
1337 if (old_result == Universe::the_null_sentinel())
1338 old_result = nullptr;
1339 return old_result;
1340 }
1341 } else {
1342 assert(result_oop != Universe::the_null_sentinel(), "");
1343 return result_oop;
1344 }
1345 }
1346
1347 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1348 Symbol* sym = unresolved_string_at(cp_index);
1349 oop str = StringTable::intern(sym, CHECK_(nullptr));
1350 assert(java_lang_String::is_instance(str), "must be string");
1351 return str;
1352 }
1353
1354 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1355 int start_arg, int end_arg,
1356 objArrayHandle info, int pos,
1357 bool must_resolve, Handle if_not_available,
1358 TRAPS) {
1359 int limit = pos + end_arg - start_arg;
1360 // checks: cp_index in range [0..this_cp->length),
1361 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1362 // info array non-null, pos..limit in [0..info.length]
1363 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1364 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1365 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1366 (0 > start_arg || start_arg > end_arg) ||
1367 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1368 (0 > pos || pos > limit) ||
1369 (info.is_null() || limit > info->length())) {
1370 // An index or something else went wrong; throw an error.
1371 // Since this is an internal API, we don't expect this,
1372 // so we don't bother to craft a nice message.
1373 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1374 }
1375 // now we can loop safely
1376 int info_i = pos;
1377 for (int i = start_arg; i < end_arg; i++) {
1378 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1379 oop arg_oop;
1380 if (must_resolve) {
1381 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1382 } else {
1383 bool found_it = false;
1384 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1385 if (!found_it) arg_oop = if_not_available();
1386 }
1387 info->obj_at_put(info_i++, arg_oop);
1388 }
1389 }
1390
1391 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1392 // If the string has already been interned, this entry will be non-null
1393 oop str = this_cp->resolved_reference_at(obj_index);
1394 assert(str != Universe::the_null_sentinel(), "");
1395 if (str != nullptr) return str;
1396 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1397 str = StringTable::intern(sym, CHECK_(nullptr));
1398 this_cp->string_at_put(obj_index, str);
1399 assert(java_lang_String::is_instance(str), "must be string");
1400 return str;
1401 }
1402
1403
1404 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1405 // Names are interned, so we can compare Symbol*s directly
1406 Symbol* cp_name = klass_name_at(cp_index);
1407 return (cp_name == k->name());
1408 }
1409
1410
1411 // Iterate over symbols and decrement ones which are Symbol*s
1412 // This is done during GC.
1413 // Only decrement the UTF8 symbols. Strings point to
1414 // these symbols but didn't increment the reference count.
1415 void ConstantPool::unreference_symbols() {
1416 for (int index = 1; index < length(); index++) { // Index 0 is unused
1417 constantTag tag = tag_at(index);
1418 if (tag.is_symbol()) {
1419 symbol_at(index)->decrement_refcount();
1420 }
1421 }
1422 }
1423
1424
1425 // Compare this constant pool's entry at index1 to the constant pool
1426 // cp2's entry at index2.
1427 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1428 int index2) {
1429
1430 // The error tags are equivalent to non-error tags when comparing
1431 jbyte t1 = tag_at(index1).non_error_value();
1432 jbyte t2 = cp2->tag_at(index2).non_error_value();
1433
1434 // Some classes are pre-resolved (like Throwable) which may lead to
1435 // consider it as a different entry. We then revert them back temporarily
1436 // to ensure proper comparison.
1437 if (t1 == JVM_CONSTANT_Class) {
1438 t1 = JVM_CONSTANT_UnresolvedClass;
1439 }
1440 if (t2 == JVM_CONSTANT_Class) {
1441 t2 = JVM_CONSTANT_UnresolvedClass;
1442 }
1443
1444 if (t1 != t2) {
1445 // Not the same entry type so there is nothing else to check. Note
1446 // that this style of checking will consider resolved/unresolved
1447 // class pairs as different.
1448 // From the ConstantPool* API point of view, this is correct
1449 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1450 // plays out in the context of ConstantPool* merging.
1451 return false;
1452 }
1453
1454 switch (t1) {
1455 case JVM_CONSTANT_ClassIndex:
1456 {
1457 int recur1 = klass_index_at(index1);
1458 int recur2 = cp2->klass_index_at(index2);
1459 if (compare_entry_to(recur1, cp2, recur2)) {
1460 return true;
1461 }
1462 } break;
1463
1464 case JVM_CONSTANT_Double:
1465 {
1466 jdouble d1 = double_at(index1);
1467 jdouble d2 = cp2->double_at(index2);
1468 if (d1 == d2) {
1469 return true;
1470 }
1471 } break;
1472
1473 case JVM_CONSTANT_Fieldref:
1474 case JVM_CONSTANT_InterfaceMethodref:
1475 case JVM_CONSTANT_Methodref:
1476 {
1477 int recur1 = uncached_klass_ref_index_at(index1);
1478 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1479 bool match = compare_entry_to(recur1, cp2, recur2);
1480 if (match) {
1481 recur1 = uncached_name_and_type_ref_index_at(index1);
1482 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1483 if (compare_entry_to(recur1, cp2, recur2)) {
1484 return true;
1485 }
1486 }
1487 } break;
1488
1489 case JVM_CONSTANT_Float:
1490 {
1491 jfloat f1 = float_at(index1);
1492 jfloat f2 = cp2->float_at(index2);
1493 if (f1 == f2) {
1494 return true;
1495 }
1496 } break;
1497
1498 case JVM_CONSTANT_Integer:
1499 {
1500 jint i1 = int_at(index1);
1501 jint i2 = cp2->int_at(index2);
1502 if (i1 == i2) {
1503 return true;
1504 }
1505 } break;
1506
1507 case JVM_CONSTANT_Long:
1508 {
1509 jlong l1 = long_at(index1);
1510 jlong l2 = cp2->long_at(index2);
1511 if (l1 == l2) {
1512 return true;
1513 }
1514 } break;
1515
1516 case JVM_CONSTANT_NameAndType:
1517 {
1518 int recur1 = name_ref_index_at(index1);
1519 int recur2 = cp2->name_ref_index_at(index2);
1520 if (compare_entry_to(recur1, cp2, recur2)) {
1521 recur1 = signature_ref_index_at(index1);
1522 recur2 = cp2->signature_ref_index_at(index2);
1523 if (compare_entry_to(recur1, cp2, recur2)) {
1524 return true;
1525 }
1526 }
1527 } break;
1528
1529 case JVM_CONSTANT_StringIndex:
1530 {
1531 int recur1 = string_index_at(index1);
1532 int recur2 = cp2->string_index_at(index2);
1533 if (compare_entry_to(recur1, cp2, recur2)) {
1534 return true;
1535 }
1536 } break;
1537
1538 case JVM_CONSTANT_UnresolvedClass:
1539 {
1540 Symbol* k1 = klass_name_at(index1);
1541 Symbol* k2 = cp2->klass_name_at(index2);
1542 if (k1 == k2) {
1543 return true;
1544 }
1545 } break;
1546
1547 case JVM_CONSTANT_MethodType:
1548 {
1549 int k1 = method_type_index_at(index1);
1550 int k2 = cp2->method_type_index_at(index2);
1551 if (compare_entry_to(k1, cp2, k2)) {
1552 return true;
1553 }
1554 } break;
1555
1556 case JVM_CONSTANT_MethodHandle:
1557 {
1558 int k1 = method_handle_ref_kind_at(index1);
1559 int k2 = cp2->method_handle_ref_kind_at(index2);
1560 if (k1 == k2) {
1561 int i1 = method_handle_index_at(index1);
1562 int i2 = cp2->method_handle_index_at(index2);
1563 if (compare_entry_to(i1, cp2, i2)) {
1564 return true;
1565 }
1566 }
1567 } break;
1568
1569 case JVM_CONSTANT_Dynamic:
1570 {
1571 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1572 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1573 int i1 = bootstrap_methods_attribute_index(index1);
1574 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1575 bool match_entry = compare_entry_to(k1, cp2, k2);
1576 bool match_bsm = compare_bootstrap_entry_to(i1, cp2, i2);
1577 return (match_entry && match_bsm);
1578 } break;
1579
1580 case JVM_CONSTANT_InvokeDynamic:
1581 {
1582 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1583 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1584 int i1 = bootstrap_methods_attribute_index(index1);
1585 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1586 bool match_entry = compare_entry_to(k1, cp2, k2);
1587 bool match_bsm = compare_bootstrap_entry_to(i1, cp2, i2);
1588 return (match_entry && match_bsm);
1589 } break;
1590
1591 case JVM_CONSTANT_String:
1592 {
1593 Symbol* s1 = unresolved_string_at(index1);
1594 Symbol* s2 = cp2->unresolved_string_at(index2);
1595 if (s1 == s2) {
1596 return true;
1597 }
1598 } break;
1599
1600 case JVM_CONSTANT_Utf8:
1601 {
1602 Symbol* s1 = symbol_at(index1);
1603 Symbol* s2 = cp2->symbol_at(index2);
1604 if (s1 == s2) {
1605 return true;
1606 }
1607 } break;
1608
1609 // Invalid is used as the tag for the second constant pool entry
1610 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1611 // not be seen by itself.
1612 case JVM_CONSTANT_Invalid: // fall through
1613
1614 default:
1615 ShouldNotReachHere();
1616 break;
1617 }
1618
1619 return false;
1620 } // end compare_entry_to()
1621
1622 // Extend the BSMAttributeEntries with the length and size of the ext_cp BSMAttributeEntries.
1623 // Used in RedefineClasses for CP merge.
1624 BSMAttributeEntries::InsertionIterator
1625 ConstantPool::start_extension(const constantPoolHandle& ext_cp, TRAPS) {
1626 BSMAttributeEntries::InsertionIterator iter =
1627 bsm_entries().start_extension(ext_cp->bsm_entries(), pool_holder()->class_loader_data(),
1628 CHECK_(BSMAttributeEntries::InsertionIterator()));
1629 return iter;
1630 }
1631
1632
1633 void ConstantPool::end_extension(BSMAttributeEntries::InsertionIterator iter, TRAPS) {
1634 bsm_entries().end_extension(iter, pool_holder()->class_loader_data(), THREAD);
1635 }
1636
1637
1638 void ConstantPool::copy_bsm_entries(const constantPoolHandle& from_cp,
1639 const constantPoolHandle& to_cp,
1640 TRAPS) {
1641 to_cp->bsm_entries().append(from_cp->bsm_entries(),
1642 to_cp->pool_holder()->class_loader_data(),
1643 THREAD);
1644 }
1645
1646
1647 // Copy this constant pool's entries at start_i to end_i (inclusive)
1648 // to the constant pool to_cp's entries starting at to_i. A total of
1649 // (end_i - start_i) + 1 entries are copied.
1650 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1651 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1652
1653
1654 int dest_cpi = to_i; // leave original alone for debug purposes
1655
1656 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1657 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1658
1659 switch (from_cp->tag_at(src_cpi).value()) {
1660 case JVM_CONSTANT_Double:
1661 case JVM_CONSTANT_Long:
1662 // double and long take two constant pool entries
1663 src_cpi += 2;
1664 dest_cpi += 2;
1665 break;
1666
1667 default:
1668 // all others take one constant pool entry
1669 src_cpi++;
1670 dest_cpi++;
1671 break;
1672 }
1673 }
1674 copy_bsm_entries(from_cp, to_cp, THREAD);
1675
1676 } // end copy_cp_to_impl()
1677
1678
1679 // Copy this constant pool's entry at from_i to the constant pool
1680 // to_cp's entry at to_i.
1681 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1682 const constantPoolHandle& to_cp, int to_i) {
1683
1684 int tag = from_cp->tag_at(from_i).value();
1685 switch (tag) {
1686 case JVM_CONSTANT_ClassIndex:
1687 {
1688 jint ki = from_cp->klass_index_at(from_i);
1689 to_cp->klass_index_at_put(to_i, ki);
1690 } break;
1691
1692 case JVM_CONSTANT_Double:
1693 {
1694 jdouble d = from_cp->double_at(from_i);
1695 to_cp->double_at_put(to_i, d);
1696 // double takes two constant pool entries so init second entry's tag
1697 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1698 } break;
1699
1700 case JVM_CONSTANT_Fieldref:
1701 {
1702 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1703 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1704 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1705 } break;
1706
1707 case JVM_CONSTANT_Float:
1708 {
1709 jfloat f = from_cp->float_at(from_i);
1710 to_cp->float_at_put(to_i, f);
1711 } break;
1712
1713 case JVM_CONSTANT_Integer:
1714 {
1715 jint i = from_cp->int_at(from_i);
1716 to_cp->int_at_put(to_i, i);
1717 } break;
1718
1719 case JVM_CONSTANT_InterfaceMethodref:
1720 {
1721 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1722 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1723 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1724 } break;
1725
1726 case JVM_CONSTANT_Long:
1727 {
1728 jlong l = from_cp->long_at(from_i);
1729 to_cp->long_at_put(to_i, l);
1730 // long takes two constant pool entries so init second entry's tag
1731 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1732 } break;
1733
1734 case JVM_CONSTANT_Methodref:
1735 {
1736 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1737 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1738 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1739 } break;
1740
1741 case JVM_CONSTANT_NameAndType:
1742 {
1743 int name_ref_index = from_cp->name_ref_index_at(from_i);
1744 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1745 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1746 } break;
1747
1748 case JVM_CONSTANT_StringIndex:
1749 {
1750 jint si = from_cp->string_index_at(from_i);
1751 to_cp->string_index_at_put(to_i, si);
1752 } break;
1753
1754 case JVM_CONSTANT_Class:
1755 case JVM_CONSTANT_UnresolvedClass:
1756 case JVM_CONSTANT_UnresolvedClassInError:
1757 {
1758 // Revert to JVM_CONSTANT_ClassIndex
1759 int name_index = from_cp->klass_slot_at(from_i).name_index();
1760 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1761 to_cp->klass_index_at_put(to_i, name_index);
1762 } break;
1763
1764 case JVM_CONSTANT_String:
1765 {
1766 Symbol* s = from_cp->unresolved_string_at(from_i);
1767 to_cp->unresolved_string_at_put(to_i, s);
1768 } break;
1769
1770 case JVM_CONSTANT_Utf8:
1771 {
1772 Symbol* s = from_cp->symbol_at(from_i);
1773 // Need to increase refcount, the old one will be thrown away and deferenced
1774 s->increment_refcount();
1775 to_cp->symbol_at_put(to_i, s);
1776 } break;
1777
1778 case JVM_CONSTANT_MethodType:
1779 case JVM_CONSTANT_MethodTypeInError:
1780 {
1781 jint k = from_cp->method_type_index_at(from_i);
1782 to_cp->method_type_index_at_put(to_i, k);
1783 } break;
1784
1785 case JVM_CONSTANT_MethodHandle:
1786 case JVM_CONSTANT_MethodHandleInError:
1787 {
1788 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1789 int k2 = from_cp->method_handle_index_at(from_i);
1790 to_cp->method_handle_index_at_put(to_i, k1, k2);
1791 } break;
1792
1793 case JVM_CONSTANT_Dynamic:
1794 case JVM_CONSTANT_DynamicInError:
1795 {
1796 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1797 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1798 k1 += to_cp->bsm_entries().array_length(); // to_cp might already have a BSM attribute
1799 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1800 } break;
1801
1802 case JVM_CONSTANT_InvokeDynamic:
1803 {
1804 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1805 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1806 k1 += to_cp->bsm_entries().array_length(); // to_cp might already have a BSM attribute
1807 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1808 } break;
1809
1810 // Invalid is used as the tag for the second constant pool entry
1811 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1812 // not be seen by itself.
1813 case JVM_CONSTANT_Invalid: // fall through
1814
1815 default:
1816 {
1817 ShouldNotReachHere();
1818 } break;
1819 }
1820 } // end copy_entry_to()
1821
1822 // Search constant pool search_cp for an entry that matches this
1823 // constant pool's entry at pattern_i. Returns the index of a
1824 // matching entry or zero (0) if there is no matching entry.
1825 int ConstantPool::find_matching_entry(int pattern_i,
1826 const constantPoolHandle& search_cp) {
1827
1828 // index zero (0) is not used
1829 for (int i = 1; i < search_cp->length(); i++) {
1830 bool found = compare_entry_to(pattern_i, search_cp, i);
1831 if (found) {
1832 return i;
1833 }
1834 }
1835
1836 return 0; // entry not found; return unused index zero (0)
1837 } // end find_matching_entry()
1838
1839
1840 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1841 // cp2's bootstrap specifier at idx2.
1842 bool ConstantPool::compare_bootstrap_entry_to(int idx1, const constantPoolHandle& cp2, int idx2) {
1843 const BSMAttributeEntry* const e1 = bsm_attribute_entry(idx1);
1844 const BSMAttributeEntry* const e2 = cp2->bsm_attribute_entry(idx2);
1845 int k1 = e1->bootstrap_method_index();
1846 int k2 = e2->bootstrap_method_index();
1847 bool match = compare_entry_to(k1, cp2, k2);
1848
1849 if (!match) {
1850 return false;
1851 }
1852
1853 const int argc = e1->argument_count();
1854 if (argc != e2->argument_count()) {
1855 return false;
1856 }
1857
1858 for (int j = 0; j < argc; j++) {
1859 k1 = e1->argument(j);
1860 k2 = e2->argument(j);
1861 match = compare_entry_to(k1, cp2, k2);
1862 if (!match) {
1863 return false;
1864 }
1865 }
1866
1867 return true; // got through loop; all elements equal
1868 } // end compare_bootstrap_entry_to()
1869
1870 // Search constant pool search_cp for a bootstrap specifier that matches
1871 // this constant pool's bootstrap specifier data at pattern_i index.
1872 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
1873 int ConstantPool::find_matching_bsm_entry(int pattern_i,
1874 const constantPoolHandle& search_cp, int offset_limit) {
1875 for (int i = 0; i < offset_limit; i++) {
1876 bool found = compare_bootstrap_entry_to(pattern_i, search_cp, i);
1877 if (found) {
1878 return i;
1879 }
1880 }
1881 return -1; // bootstrap specifier data not found; return unused index (-1)
1882 } // end find_matching_bsm_entry()
1883
1884
1885 #ifndef PRODUCT
1886
1887 const char* ConstantPool::printable_name_at(int cp_index) {
1888
1889 constantTag tag = tag_at(cp_index);
1890
1891 if (tag.is_string()) {
1892 return string_at_noresolve(cp_index);
1893 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1894 return klass_name_at(cp_index)->as_C_string();
1895 } else if (tag.is_symbol()) {
1896 return symbol_at(cp_index)->as_C_string();
1897 }
1898 return "";
1899 }
1900
1901 #endif // PRODUCT
1902
1903
1904 // Returns size of constant pool entry.
1905 jint ConstantPool::cpool_entry_size(jint idx) {
1906 switch(tag_at(idx).value()) {
1907 case JVM_CONSTANT_Invalid:
1908 case JVM_CONSTANT_Unicode:
1909 return 1;
1910
1911 case JVM_CONSTANT_Utf8:
1912 return 3 + symbol_at(idx)->utf8_length();
1913
1914 case JVM_CONSTANT_Class:
1915 case JVM_CONSTANT_String:
1916 case JVM_CONSTANT_ClassIndex:
1917 case JVM_CONSTANT_UnresolvedClass:
1918 case JVM_CONSTANT_UnresolvedClassInError:
1919 case JVM_CONSTANT_StringIndex:
1920 case JVM_CONSTANT_MethodType:
1921 case JVM_CONSTANT_MethodTypeInError:
1922 return 3;
1923
1924 case JVM_CONSTANT_MethodHandle:
1925 case JVM_CONSTANT_MethodHandleInError:
1926 return 4; //tag, ref_kind, ref_index
1927
1928 case JVM_CONSTANT_Integer:
1929 case JVM_CONSTANT_Float:
1930 case JVM_CONSTANT_Fieldref:
1931 case JVM_CONSTANT_Methodref:
1932 case JVM_CONSTANT_InterfaceMethodref:
1933 case JVM_CONSTANT_NameAndType:
1934 return 5;
1935
1936 case JVM_CONSTANT_Dynamic:
1937 case JVM_CONSTANT_DynamicInError:
1938 case JVM_CONSTANT_InvokeDynamic:
1939 // u1 tag, u2 bsm, u2 nt
1940 return 5;
1941
1942 case JVM_CONSTANT_Long:
1943 case JVM_CONSTANT_Double:
1944 return 9;
1945 }
1946 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1947 return 1;
1948 } /* end cpool_entry_size */
1949
1950
1951 // SymbolHash is used to find a constant pool index from a string.
1952 // This function fills in SymbolHashs, one for utf8s and one for
1953 // class names, returns size of the cpool raw bytes.
1954 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
1955 SymbolHash *classmap) {
1956 jint size = 0;
1957
1958 for (u2 idx = 1; idx < length(); idx++) {
1959 u2 tag = tag_at(idx).value();
1960 size += cpool_entry_size(idx);
1961
1962 switch(tag) {
1963 case JVM_CONSTANT_Utf8: {
1964 Symbol* sym = symbol_at(idx);
1965 symmap->add_if_absent(sym, idx);
1966 break;
1967 }
1968 case JVM_CONSTANT_Class:
1969 case JVM_CONSTANT_UnresolvedClass:
1970 case JVM_CONSTANT_UnresolvedClassInError: {
1971 Symbol* sym = klass_name_at(idx);
1972 classmap->add_if_absent(sym, idx);
1973 break;
1974 }
1975 case JVM_CONSTANT_Long:
1976 case JVM_CONSTANT_Double: {
1977 idx++; // Both Long and Double take two cpool slots
1978 break;
1979 }
1980 }
1981 }
1982 return size;
1983 } /* end hash_utf8_entries_to */
1984
1985
1986 // Copy cpool bytes.
1987 // Returns:
1988 // 0, in case of OutOfMemoryError
1989 // -1, in case of internal error
1990 // > 0, count of the raw cpool bytes that have been copied
1991 int ConstantPool::copy_cpool_bytes(int cpool_size,
1992 SymbolHash* tbl,
1993 unsigned char *bytes) {
1994 u2 idx1, idx2;
1995 jint size = 0;
1996 jint cnt = length();
1997 unsigned char *start_bytes = bytes;
1998
1999 for (jint idx = 1; idx < cnt; idx++) {
2000 u1 tag = tag_at(idx).value();
2001 jint ent_size = cpool_entry_size(idx);
2002
2003 assert(size + ent_size <= cpool_size, "Size mismatch");
2004
2005 *bytes = tag;
2006 switch(tag) {
2007 case JVM_CONSTANT_Invalid: {
2008 break;
2009 }
2010 case JVM_CONSTANT_Unicode: {
2011 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2012 break;
2013 }
2014 case JVM_CONSTANT_Utf8: {
2015 Symbol* sym = symbol_at(idx);
2016 char* str = sym->as_utf8();
2017 // Warning! It's crashing on x86 with len = sym->utf8_length()
2018 int len = (int) strlen(str);
2019 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2020 for (int i = 0; i < len; i++) {
2021 bytes[3+i] = (u1) str[i];
2022 }
2023 break;
2024 }
2025 case JVM_CONSTANT_Integer: {
2026 jint val = int_at(idx);
2027 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2028 break;
2029 }
2030 case JVM_CONSTANT_Float: {
2031 jfloat val = float_at(idx);
2032 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2033 break;
2034 }
2035 case JVM_CONSTANT_Long: {
2036 jlong val = long_at(idx);
2037 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2038 idx++; // Long takes two cpool slots
2039 break;
2040 }
2041 case JVM_CONSTANT_Double: {
2042 jdouble val = double_at(idx);
2043 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2044 idx++; // Double takes two cpool slots
2045 break;
2046 }
2047 case JVM_CONSTANT_Class:
2048 case JVM_CONSTANT_UnresolvedClass:
2049 case JVM_CONSTANT_UnresolvedClassInError: {
2050 *bytes = JVM_CONSTANT_Class;
2051 Symbol* sym = klass_name_at(idx);
2052 idx1 = tbl->symbol_to_value(sym);
2053 assert(idx1 != 0, "Have not found a hashtable entry");
2054 Bytes::put_Java_u2((address) (bytes+1), idx1);
2055 break;
2056 }
2057 case JVM_CONSTANT_String: {
2058 *bytes = JVM_CONSTANT_String;
2059 Symbol* sym = unresolved_string_at(idx);
2060 idx1 = tbl->symbol_to_value(sym);
2061 assert(idx1 != 0, "Have not found a hashtable entry");
2062 Bytes::put_Java_u2((address) (bytes+1), idx1);
2063 break;
2064 }
2065 case JVM_CONSTANT_Fieldref:
2066 case JVM_CONSTANT_Methodref:
2067 case JVM_CONSTANT_InterfaceMethodref: {
2068 idx1 = uncached_klass_ref_index_at(idx);
2069 idx2 = uncached_name_and_type_ref_index_at(idx);
2070 Bytes::put_Java_u2((address) (bytes+1), idx1);
2071 Bytes::put_Java_u2((address) (bytes+3), idx2);
2072 break;
2073 }
2074 case JVM_CONSTANT_NameAndType: {
2075 idx1 = name_ref_index_at(idx);
2076 idx2 = signature_ref_index_at(idx);
2077 Bytes::put_Java_u2((address) (bytes+1), idx1);
2078 Bytes::put_Java_u2((address) (bytes+3), idx2);
2079 break;
2080 }
2081 case JVM_CONSTANT_ClassIndex: {
2082 *bytes = JVM_CONSTANT_Class;
2083 idx1 = checked_cast<u2>(klass_index_at(idx));
2084 Bytes::put_Java_u2((address) (bytes+1), idx1);
2085 break;
2086 }
2087 case JVM_CONSTANT_StringIndex: {
2088 *bytes = JVM_CONSTANT_String;
2089 idx1 = checked_cast<u2>(string_index_at(idx));
2090 Bytes::put_Java_u2((address) (bytes+1), idx1);
2091 break;
2092 }
2093 case JVM_CONSTANT_MethodHandle:
2094 case JVM_CONSTANT_MethodHandleInError: {
2095 *bytes = JVM_CONSTANT_MethodHandle;
2096 int kind = method_handle_ref_kind_at(idx);
2097 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2098 *(bytes+1) = (unsigned char) kind;
2099 Bytes::put_Java_u2((address) (bytes+2), idx1);
2100 break;
2101 }
2102 case JVM_CONSTANT_MethodType:
2103 case JVM_CONSTANT_MethodTypeInError: {
2104 *bytes = JVM_CONSTANT_MethodType;
2105 idx1 = checked_cast<u2>(method_type_index_at(idx));
2106 Bytes::put_Java_u2((address) (bytes+1), idx1);
2107 break;
2108 }
2109 case JVM_CONSTANT_Dynamic:
2110 case JVM_CONSTANT_DynamicInError: {
2111 *bytes = tag;
2112 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2113 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2114 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2115 Bytes::put_Java_u2((address) (bytes+1), idx1);
2116 Bytes::put_Java_u2((address) (bytes+3), idx2);
2117 break;
2118 }
2119 case JVM_CONSTANT_InvokeDynamic: {
2120 *bytes = tag;
2121 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2122 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2123 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2124 Bytes::put_Java_u2((address) (bytes+1), idx1);
2125 Bytes::put_Java_u2((address) (bytes+3), idx2);
2126 break;
2127 }
2128 }
2129 bytes += ent_size;
2130 size += ent_size;
2131 }
2132 assert(size == cpool_size, "Size mismatch");
2133
2134 return (int)(bytes - start_bytes);
2135 } /* end copy_cpool_bytes */
2136
2137 bool ConstantPool::is_maybe_on_stack() const {
2138 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2139 if (!Continuations::enabled()) {
2140 return false;
2141 }
2142
2143 // If the condition below is true, it means that the nmethod was found to
2144 // be alive the previous completed marking cycle.
2145 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2146 }
2147
2148 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2149 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2150 // memory for the method is reclaimed.
2151 bool ConstantPool::on_stack() const {
2152 if ((_flags &_on_stack) != 0) {
2153 return true;
2154 }
2155
2156 if (_cache == nullptr) {
2157 return false;
2158 }
2159
2160 return is_maybe_on_stack();
2161 }
2162
2163 void ConstantPool::set_on_stack(const bool value) {
2164 if (value) {
2165 // Only record if it's not already set.
2166 if (!on_stack()) {
2167 assert(!in_aot_cache(), "should always be set for constant pools in AOT cache");
2168 _flags |= _on_stack;
2169 MetadataOnStackMark::record(this);
2170 }
2171 } else {
2172 // Clearing is done single-threadedly.
2173 if (!in_aot_cache()) {
2174 _flags &= (u2)(~_on_stack);
2175 }
2176 }
2177 }
2178
2179 // Printing
2180
2181 void ConstantPool::print_on(outputStream* st) const {
2182 assert(is_constantPool(), "must be constantPool");
2183 st->print_cr("%s", internal_name());
2184 if (flags() != 0) {
2185 st->print(" - flags: 0x%x", flags());
2186 if (has_preresolution()) st->print(" has_preresolution");
2187 if (on_stack()) st->print(" on_stack");
2188 st->cr();
2189 }
2190 if (pool_holder() != nullptr) {
2191 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2192 }
2193 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2194 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2195 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2196 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2197 st->print_cr(" - cp length: %d", length());
2198
2199 for (int index = 1; index < length(); index++) { // Index 0 is unused
2200 ((ConstantPool*)this)->print_entry_on(index, st);
2201 switch (tag_at(index).value()) {
2202 case JVM_CONSTANT_Long :
2203 case JVM_CONSTANT_Double :
2204 index++; // Skip entry following eigth-byte constant
2205 }
2206
2207 }
2208 st->cr();
2209 }
2210
2211 // Print one constant pool entry
2212 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2213 EXCEPTION_MARK;
2214 st->print(" - %3d : ", cp_index);
2215 tag_at(cp_index).print_on(st);
2216 st->print(" : ");
2217 switch (tag_at(cp_index).value()) {
2218 case JVM_CONSTANT_Class :
2219 { Klass* k = klass_at(cp_index, CATCH);
2220 guarantee(k != nullptr, "need klass");
2221 k->print_value_on(st);
2222 st->print(" {" PTR_FORMAT "}", p2i(k));
2223 }
2224 break;
2225 case JVM_CONSTANT_Fieldref :
2226 case JVM_CONSTANT_Methodref :
2227 case JVM_CONSTANT_InterfaceMethodref :
2228 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2229 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2230 break;
2231 case JVM_CONSTANT_String :
2232 unresolved_string_at(cp_index)->print_value_on(st);
2233 break;
2234 case JVM_CONSTANT_Integer :
2235 st->print("%d", int_at(cp_index));
2236 break;
2237 case JVM_CONSTANT_Float :
2238 st->print("%f", float_at(cp_index));
2239 break;
2240 case JVM_CONSTANT_Long :
2241 st->print_jlong(long_at(cp_index));
2242 break;
2243 case JVM_CONSTANT_Double :
2244 st->print("%lf", double_at(cp_index));
2245 break;
2246 case JVM_CONSTANT_NameAndType :
2247 st->print("name_index=%d", name_ref_index_at(cp_index));
2248 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2249 break;
2250 case JVM_CONSTANT_Utf8 :
2251 symbol_at(cp_index)->print_value_on(st);
2252 break;
2253 case JVM_CONSTANT_ClassIndex: {
2254 int name_index = *int_at_addr(cp_index);
2255 st->print("klass_index=%d ", name_index);
2256 symbol_at(name_index)->print_value_on(st);
2257 }
2258 break;
2259 case JVM_CONSTANT_UnresolvedClass : // fall-through
2260 case JVM_CONSTANT_UnresolvedClassInError: {
2261 CPKlassSlot kslot = klass_slot_at(cp_index);
2262 int resolved_klass_index = kslot.resolved_klass_index();
2263 int name_index = kslot.name_index();
2264 assert(tag_at(name_index).is_symbol(), "sanity");
2265 symbol_at(name_index)->print_value_on(st);
2266 }
2267 break;
2268 case JVM_CONSTANT_MethodHandle :
2269 case JVM_CONSTANT_MethodHandleInError :
2270 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2271 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2272 break;
2273 case JVM_CONSTANT_MethodType :
2274 case JVM_CONSTANT_MethodTypeInError :
2275 st->print("signature_index=%d", method_type_index_at(cp_index));
2276 break;
2277 case JVM_CONSTANT_Dynamic :
2278 case JVM_CONSTANT_DynamicInError :
2279 {
2280 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2281 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2282 int argc = bootstrap_argument_count_at(cp_index);
2283 if (argc > 0) {
2284 for (int arg_i = 0; arg_i < argc; arg_i++) {
2285 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2286 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2287 }
2288 st->print("}");
2289 }
2290 }
2291 break;
2292 case JVM_CONSTANT_InvokeDynamic :
2293 {
2294 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2295 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2296 int argc = bootstrap_argument_count_at(cp_index);
2297 if (argc > 0) {
2298 for (int arg_i = 0; arg_i < argc; arg_i++) {
2299 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2300 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2301 }
2302 st->print("}");
2303 }
2304 }
2305 break;
2306 default:
2307 ShouldNotReachHere();
2308 break;
2309 }
2310 st->cr();
2311 }
2312
2313 void ConstantPool::print_value_on(outputStream* st) const {
2314 assert(is_constantPool(), "must be constantPool");
2315 st->print("constant pool [%d]", length());
2316 if (has_preresolution()) st->print("/preresolution");
2317 if (!bsm_entries().is_empty()) st->print("/BSMs[%d]", bsm_entries().bootstrap_methods()->length());
2318 print_address_on(st);
2319 if (pool_holder() != nullptr) {
2320 st->print(" for ");
2321 pool_holder()->print_value_on(st);
2322 bool extra = (pool_holder()->constants() != this);
2323 if (extra) st->print(" (extra)");
2324 }
2325 if (cache() != nullptr) {
2326 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2327 }
2328 }
2329
2330 // Verification
2331
2332 void ConstantPool::verify_on(outputStream* st) {
2333 guarantee(is_constantPool(), "object must be constant pool");
2334 for (int i = 0; i< length(); i++) {
2335 constantTag tag = tag_at(i);
2336 if (tag.is_klass() || tag.is_unresolved_klass()) {
2337 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2338 } else if (tag.is_symbol()) {
2339 Symbol* entry = symbol_at(i);
2340 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2341 } else if (tag.is_string()) {
2342 Symbol* entry = unresolved_string_at(i);
2343 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2344 }
2345 }
2346 if (pool_holder() != nullptr) {
2347 // Note: pool_holder() can be null in temporary constant pools
2348 // used during constant pool merging
2349 guarantee(pool_holder()->is_klass(), "should be klass");
2350 }
2351 }
2352
2353 void BSMAttributeEntries::deallocate_contents(ClassLoaderData* loader_data) {
2354 MetadataFactory::free_array<u4>(loader_data, this->_offsets);
2355 MetadataFactory::free_array<u2>(loader_data, this->_bootstrap_methods);
2356 this->_offsets = nullptr;
2357 this->_bootstrap_methods = nullptr;
2358 }
2359
2360 void BSMAttributeEntries::copy_into(InsertionIterator& iter, int num_entries) const {
2361 assert(num_entries + iter._cur_offset <= iter._insert_into->_offsets->length(), "must");
2362 for (int i = 0; i < num_entries; i++) {
2363 const BSMAttributeEntry* e = entry(i);
2364 BSMAttributeEntry* e_new = iter.reserve_new_entry(e->bootstrap_method_index(), e->argument_count());
2365 assert(e_new != nullptr, "must be");
2366 e->copy_args_into(e_new);
2367 }
2368 }
2369
2370 BSMAttributeEntries::InsertionIterator
2371 BSMAttributeEntries::start_extension(const BSMAttributeEntries& other, ClassLoaderData* loader_data, TRAPS) {
2372 InsertionIterator iter = start_extension(other.number_of_entries(), other.array_length(),
2373 loader_data, CHECK_(BSMAttributeEntries::InsertionIterator()));
2374 return iter;
2375 }
2376
2377 BSMAttributeEntries::InsertionIterator
2378 BSMAttributeEntries::start_extension(int number_of_entries, int array_length,
2379 ClassLoaderData* loader_data, TRAPS) {
2380 InsertionIterator extension_iterator(this, this->number_of_entries(), this->array_length());
2381 int new_number_of_entries = this->number_of_entries() + number_of_entries;
2382 int new_array_length = this->array_length() + array_length;
2383 int invalid_index = new_array_length;
2384
2385 Array<u4>* new_offsets =
2386 MetadataFactory::new_array<u4>(loader_data, new_number_of_entries, invalid_index, CHECK_(InsertionIterator()));
2387 Array<u2>* new_array = MetadataFactory::new_array<u2>(loader_data, new_array_length, CHECK_(InsertionIterator()));
2388 { // Copy over all the old BSMAEntry's and their respective offsets
2389 BSMAttributeEntries carrier(new_offsets, new_array);
2390 InsertionIterator copy_iter(&carrier, 0, 0);
2391 copy_into(copy_iter, this->number_of_entries());
2392 }
2393 // Replace content
2394 deallocate_contents(loader_data);
2395 _offsets = new_offsets;
2396 _bootstrap_methods = new_array;
2397 return extension_iterator;
2398 }
2399
2400
2401 void BSMAttributeEntries::append(const BSMAttributeEntries& other, ClassLoaderData* loader_data, TRAPS) {
2402 if (other.number_of_entries() == 0) {
2403 return; // Done!
2404 }
2405 InsertionIterator iter = start_extension(other, loader_data, CHECK);
2406 other.copy_into(iter, other.number_of_entries());
2407 end_extension(iter, loader_data, THREAD);
2408 }
2409
2410 void BSMAttributeEntries::end_extension(InsertionIterator& iter, ClassLoaderData* loader_data, TRAPS) {
2411 assert(iter._insert_into == this, "must be");
2412 assert(iter._cur_offset <= this->_offsets->length(), "must be");
2413 assert(iter._cur_array <= this->_bootstrap_methods->length(), "must be");
2414
2415 // Did we fill up all of the available space? If so, do nothing.
2416 if (iter._cur_offset == this->_offsets->length() &&
2417 iter._cur_array == this->_bootstrap_methods->length()) {
2418 return;
2419 }
2420
2421 // We used less, truncate by allocating new arrays
2422 Array<u4>* new_offsets =
2423 MetadataFactory::new_array<u4>(loader_data, iter._cur_offset, 0, CHECK);
2424 Array<u2>* new_array =
2425 MetadataFactory::new_array<u2>(loader_data, iter._cur_array, CHECK);
2426 { // Copy over the constructed BSMAEntry's
2427 BSMAttributeEntries carrier(new_offsets, new_array);
2428 InsertionIterator copy_iter(&carrier, 0, 0);
2429 copy_into(copy_iter, iter._cur_offset);
2430 }
2431
2432 deallocate_contents(loader_data);
2433 _offsets = new_offsets;
2434 _bootstrap_methods = new_array;
2435 }