1 /*
2 * Copyright (c) 1997, 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/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/oopCast.inline.hpp"
61 #include "oops/refArrayOop.hpp"
62 #include "oops/typeArrayOop.inline.hpp"
63 #include "prims/jvmtiExport.hpp"
64 #include "runtime/atomicAccess.hpp"
65 #include "runtime/fieldDescriptor.inline.hpp"
66 #include "runtime/handles.inline.hpp"
67 #include "runtime/init.hpp"
68 #include "runtime/javaCalls.hpp"
69 #include "runtime/javaThread.inline.hpp"
70 #include "runtime/perfData.hpp"
71 #include "runtime/signature.hpp"
72 #include "runtime/vframe.inline.hpp"
73 #include "utilities/checkedCast.hpp"
74 #include "utilities/copy.hpp"
75
76 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
77 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
78 int size = ConstantPool::size(length);
79 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
80 }
81
82 void ConstantPool::copy_fields(const ConstantPool* orig) {
83 // Preserve dynamic constant information from the original pool
84 if (orig->has_dynamic_constant()) {
85 set_has_dynamic_constant();
86 }
87
88 set_major_version(orig->major_version());
89 set_minor_version(orig->minor_version());
90
91 set_source_file_name_index(orig->source_file_name_index());
92 set_generic_signature_index(orig->generic_signature_index());
93 }
94
95 #ifdef ASSERT
96
97 // MetaspaceObj allocation invariant is calloc equivalent memory
98 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
99 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
100 assert(tags != nullptr, "invariant");
101 const int length = tags->length();
102 for (int index = 0; index < length; ++index) {
103 if (JVM_CONSTANT_Invalid != tags->at(index)) {
104 return false;
105 }
106 }
107 return true;
108 }
109
110 #endif
111
112 ConstantPool::ConstantPool() {
113 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
114 }
115
116 ConstantPool::ConstantPool(Array<u1>* tags) :
117 _tags(tags),
118 _length(tags->length()) {
119
120 assert(_tags != nullptr, "invariant");
121 assert(tags->length() == _length, "invariant");
122 assert(tag_array_is_zero_initialized(tags), "invariant");
123 assert(0 == flags(), "invariant");
124 assert(0 == version(), "invariant");
125 assert(nullptr == _pool_holder, "invariant");
126 }
127
128 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
129 if (cache() != nullptr) {
130 MetadataFactory::free_metadata(loader_data, cache());
131 set_cache(nullptr);
132 }
133
134 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
135 set_resolved_klasses(nullptr);
136
137 bsm_entries().deallocate_contents(loader_data);
138
139 release_C_heap_structures();
140
141 // free tag array
142 MetadataFactory::free_array<u1>(loader_data, tags());
143 set_tags(nullptr);
144 }
145
146 void ConstantPool::release_C_heap_structures() {
147 // walk constant pool and decrement symbol reference counts
148 unreference_symbols();
149 }
150
151 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
152 log_trace(aot)("Iter(ConstantPool): %p", this);
153
154 it->push(&_tags, MetaspaceClosure::_writable);
155 it->push(&_cache);
156 it->push(&_pool_holder);
157 it->push(&bsm_entries().offsets());
158 it->push(&bsm_entries().bootstrap_methods());
159 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
160
161 for (int i = 0; i < length(); i++) {
162 // The only MSO's embedded in the CP entries are Symbols:
163 // JVM_CONSTANT_String
164 // JVM_CONSTANT_Utf8
165 constantTag ctag = tag_at(i);
166 if (ctag.is_string() || ctag.is_utf8()) {
167 it->push(symbol_at_addr(i));
168 }
169 }
170 }
171
172 refArrayOop ConstantPool::resolved_references() const {
173 return _cache->resolved_references();
174 }
175
176 // Called from outside constant pool resolution where a resolved_reference array
177 // may not be present.
178 refArrayOop ConstantPool::resolved_references_or_null() const {
179 if (_cache == nullptr) {
180 return nullptr;
181 } else {
182 return _cache->resolved_references();
183 }
184 }
185
186 oop ConstantPool::resolved_reference_at(int index) const {
187 oop result = resolved_references()->obj_at(index);
188 assert(oopDesc::is_oop_or_null(result), "Must be oop");
189 return result;
190 }
191
192 // Use a CAS for multithreaded access
193 oop ConstantPool::set_resolved_reference_at(int index, oop new_result) {
194 assert(oopDesc::is_oop_or_null(new_result), "Must be oop");
195 return oop_cast<refArrayOop>(resolved_references())->replace_if_null(index, new_result);
196 }
197
198 // Create resolved_references array and mapping array for original cp indexes
199 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
200 // to map it back for resolving and some unlikely miscellaneous uses.
201 // The objects created by invokedynamic are appended to this list.
202 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
203 const intStack& reference_map,
204 int constant_pool_map_length,
205 TRAPS) {
206 // Initialized the resolved object cache.
207 int map_length = reference_map.length();
208 if (map_length > 0) {
209 // Only need mapping back to constant pool entries. The map isn't used for
210 // invokedynamic resolved_reference entries. For invokedynamic entries,
211 // the constant pool cache index has the mapping back to both the constant
212 // pool and to the resolved reference index.
213 if (constant_pool_map_length > 0) {
214 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
215
216 for (int i = 0; i < constant_pool_map_length; i++) {
217 int x = reference_map.at(i);
218 assert(x == (int)(jushort) x, "klass index is too big");
219 om->at_put(i, (jushort)x);
220 }
221 set_reference_map(om);
222 }
223
224 // Create Java array for holding resolved strings, methodHandles,
225 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
226 refArrayOop stom = oopFactory::new_refArray(vmClasses::Object_klass(), map_length, CHECK);
227 HandleMark hm(THREAD);
228 Handle refs_handle (THREAD, stom); // must handleize.
229 set_resolved_references(loader_data->add_handle(refs_handle));
230
231 // Create a "scratch" copy of the resolved references array to archive
232 if (CDSConfig::is_dumping_heap()) {
233 refArrayOop scratch_references = oopFactory::new_refArray(vmClasses::Object_klass(), map_length, CHECK);
234 HeapShared::add_scratch_resolved_references(this, scratch_references);
235 }
236 }
237 }
238
239 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
240 // A ConstantPool can't possibly have 0xffff valid class entries,
241 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
242 // entry for the class's name. So at most we will have 0xfffe class entries.
243 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
244 // UnresolvedKlass entries that are temporarily created during class redefinition.
245 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
246 assert(resolved_klasses() == nullptr, "sanity");
247 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
248 set_resolved_klasses(rk);
249 }
250
251 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
252 int len = length();
253 int num_klasses = 0;
254 for (int i = 1; i <len; i++) {
255 switch (tag_at(i).value()) {
256 case JVM_CONSTANT_ClassIndex:
257 {
258 const int class_index = klass_index_at(i);
259 unresolved_klass_at_put(i, class_index, num_klasses++);
260 }
261 break;
262 #ifndef PRODUCT
263 case JVM_CONSTANT_Class:
264 case JVM_CONSTANT_UnresolvedClass:
265 case JVM_CONSTANT_UnresolvedClassInError:
266 // All of these should have been reverted back to Unresolved before calling
267 // this function.
268 ShouldNotReachHere();
269 #endif
270 }
271 }
272 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
273 }
274
275 // Hidden class support:
276 void ConstantPool::klass_at_put(int class_index, Klass* k) {
277 assert(k != nullptr, "must be valid klass");
278 CPKlassSlot kslot = klass_slot_at(class_index);
279 int resolved_klass_index = kslot.resolved_klass_index();
280 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
281 AtomicAccess::release_store(adr, k);
282
283 // The interpreter assumes when the tag is stored, the klass is resolved
284 // and the Klass* non-null, so we need hardware store ordering here.
285 release_tag_at_put(class_index, JVM_CONSTANT_Class);
286 }
287
288 #if INCLUDE_CDS_JAVA_HEAP
289 template <typename Function>
290 void ConstantPool::iterate_archivable_resolved_references(Function function) {
291 objArrayOop rr = resolved_references();
292 if (rr != nullptr && cache() != nullptr && CDSConfig::is_dumping_method_handles()) {
293 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
294 if (indy_entries != nullptr) {
295 for (int i = 0; i < indy_entries->length(); i++) {
296 ResolvedIndyEntry *rie = indy_entries->adr_at(i);
297 if (rie->is_resolved() && AOTConstantPoolResolver::is_resolution_deterministic(this, rie->constant_pool_index())) {
298 int rr_index = rie->resolved_references_index();
299 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
300 function(rr_index);
301
302 // Save the BSM as well (sometimes the JIT looks up the BSM it for replay)
303 int indy_cp_index = rie->constant_pool_index();
304 int bsm_mh_cp_index = bootstrap_method_ref_index_at(indy_cp_index);
305 int bsm_rr_index = cp_to_object_index(bsm_mh_cp_index);
306 assert(resolved_reference_at(bsm_rr_index) != nullptr, "must exist");
307 function(bsm_rr_index);
308 }
309 }
310 }
311
312 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
313 if (method_entries != nullptr) {
314 for (int i = 0; i < method_entries->length(); i++) {
315 ResolvedMethodEntry* rme = method_entries->adr_at(i);
316 const char* rejection_reason = nullptr;
317 if (rme->is_resolved(Bytecodes::_invokehandle) && rme->has_appendix() &&
318 cache()->can_archive_resolved_method(this, rme, rejection_reason)) {
319 int rr_index = rme->resolved_references_index();
320 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
321 function(rr_index);
322 }
323 }
324 }
325 }
326 }
327
328 // Returns the _resolved_reference array after removing unarchivable items from it.
329 // Returns null if this class is not supported, or _resolved_reference doesn't exist.
330 refArrayOop ConstantPool::prepare_resolved_references_for_archiving() {
331 if (_cache == nullptr) {
332 return nullptr; // nothing to do
333 }
334
335 InstanceKlass *ik = pool_holder();
336 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
337 // Archiving resolved references for classes from non-builtin loaders
338 // is not yet supported.
339 return nullptr;
340 }
341
342 refArrayOop rr = resolved_references();
343 if (rr != nullptr) {
344 ResourceMark rm;
345 int rr_len = rr->length();
346 GrowableArray<bool> keep_resolved_refs(rr_len, rr_len, false);
347
348 iterate_archivable_resolved_references([&](int rr_index) {
349 keep_resolved_refs.at_put(rr_index, true);
350 });
351
352 refArrayOop scratch_rr = HeapShared::scratch_resolved_references(this);
353 Array<u2>* ref_map = reference_map();
354 int ref_map_len = ref_map == nullptr ? 0 : ref_map->length();
355 for (int i = 0; i < rr_len; i++) {
356 oop obj = rr->obj_at(i);
357 scratch_rr->obj_at_put(i, nullptr);
358 if (obj != nullptr) {
359 if (i < ref_map_len) {
360 int index = object_to_cp_index(i);
361 if (tag_at(index).is_string()) {
362 assert(java_lang_String::is_instance(obj), "must be");
363 if (!HeapShared::is_string_too_large_to_archive(obj)) {
364 scratch_rr->obj_at_put(i, obj);
365 }
366 continue;
367 }
368 }
369
370 if (keep_resolved_refs.at(i)) {
371 scratch_rr->obj_at_put(i, obj);
372 }
373 }
374 }
375 return scratch_rr;
376 }
377 return rr;
378 }
379 #endif
380
381 #if INCLUDE_CDS
382 // CDS support. Create a new resolved_references array.
383 void ConstantPool::restore_unshareable_info(TRAPS) {
384 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
385 return;
386 }
387 assert(is_constantPool(), "ensure C++ vtable is restored");
388 assert(on_stack(), "should always be set for constant pools in AOT cache");
389 assert(in_aot_cache(), "should always be set for constant pools in AOT cache");
390 if (is_for_method_handle_intrinsic()) {
391 // See the same check in remove_unshareable_info() below.
392 assert(cache() == nullptr, "must not have cpCache");
393 return;
394 }
395 assert(_cache != nullptr, "constant pool _cache should not be null");
396
397 // Only create the new resolved references array if it hasn't been attempted before
398 if (resolved_references() != nullptr) return;
399
400 if (vmClasses::Object_klass_is_loaded()) {
401 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
402 #if INCLUDE_CDS_JAVA_HEAP
403 if (HeapShared::is_archived_heap_in_use() &&
404 _cache->archived_references() != nullptr) {
405 oop archived = _cache->archived_references();
406 // Create handle for the archived resolved reference array object
407 HandleMark hm(THREAD);
408 Handle refs_handle(THREAD, archived);
409 set_resolved_references(loader_data->add_handle(refs_handle));
410 _cache->clear_archived_references();
411 } else
412 #endif
413 {
414 // No mapped archived resolved reference array
415 // Recreate the object array and add to ClassLoaderData.
416 int map_length = resolved_reference_length();
417 if (map_length > 0) {
418 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
419 HandleMark hm(THREAD);
420 Handle refs_handle(THREAD, stom); // must handleize.
421 set_resolved_references(loader_data->add_handle(refs_handle));
422 }
423 }
424 }
425
426 if (CDSConfig::is_dumping_final_static_archive() && CDSConfig::is_dumping_heap() && resolved_references() != nullptr) {
427 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), resolved_references()->length(), CHECK);
428 HeapShared::add_scratch_resolved_references(this, scratch_references);
429 }
430 }
431
432 void ConstantPool::remove_unshareable_info() {
433 // ConstantPools in AOT cache are in the RO region, so the _flags cannot be modified.
434 // The _on_stack flag is used to prevent ConstantPools from deallocation during
435 // class redefinition. Since such ConstantPools cannot be deallocated anyway,
436 // we always set _on_stack to true to avoid having to change _flags during runtime.
437 _flags |= (_on_stack | _in_aot_cache);
438
439 if (is_for_method_handle_intrinsic()) {
440 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
441 // that need to be removed/restored. It has no cpCache since the intrinsic methods
442 // don't have any bytecodes.
443 assert(cache() == nullptr, "must not have cpCache");
444 return;
445 }
446
447 bool update_resolved_reference = true;
448 if (CDSConfig::is_dumping_final_static_archive()) {
449 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
450 InstanceKlass* src_holder = src_cp->pool_holder();
451 if (src_holder->defined_by_other_loaders()) {
452 // Unregistered classes are not loaded in the AOT assembly phase. The resolved reference length
453 // is already saved during the training run.
454 precond(!src_holder->is_loaded());
455 precond(resolved_reference_length() >= 0);
456 precond(resolved_references() == nullptr);
457 update_resolved_reference = false;
458 }
459 }
460
461 // resolved_references(): remember its length. If it cannot be restored
462 // from the archived heap objects at run time, we need to dynamically allocate it.
463 if (update_resolved_reference && cache() != nullptr) {
464 set_resolved_reference_length(
465 resolved_references() != nullptr ? resolved_references()->length() : 0);
466 set_resolved_references(OopHandle());
467 }
468 remove_unshareable_entries();
469 }
470
471 static const char* get_type(Klass* k) {
472 const char* type;
473 Klass* src_k;
474 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
475 src_k = ArchiveBuilder::current()->get_source_addr(k);
476 } else {
477 src_k = k;
478 }
479
480 if (src_k->is_objArray_klass()) {
481 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
482 assert(!src_k->is_objArray_klass(), "sanity");
483 assert(src_k->is_instance_klass() || src_k->is_typeArray_klass(), "Sanity check");
484 }
485
486 if (src_k->is_typeArray_klass()) {
487 type = "prim";
488 } else {
489 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
490 if (src_ik->defined_by_boot_loader()) {
491 return "boot";
492 } else if (src_ik->defined_by_platform_loader()) {
493 return "plat";
494 } else if (src_ik->defined_by_app_loader()) {
495 return "app";
496 } else {
497 return "unreg";
498 }
499 }
500
501 return type;
502 }
503
504 void ConstantPool::remove_unshareable_entries() {
505 ResourceMark rm;
506 log_info(aot, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
507 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
508 int cp_tag = tag_at(cp_index).value();
509 switch (cp_tag) {
510 case JVM_CONSTANT_UnresolvedClass:
511 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, false);
512 break;
513 case JVM_CONSTANT_UnresolvedClassInError:
514 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
515 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, true);
516 break;
517 case JVM_CONSTANT_MethodHandleInError:
518 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
519 break;
520 case JVM_CONSTANT_MethodTypeInError:
521 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
522 break;
523 case JVM_CONSTANT_DynamicInError:
524 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
525 break;
526 case JVM_CONSTANT_Class:
527 remove_resolved_klass_if_non_deterministic(cp_index);
528 break;
529 default:
530 break;
531 }
532 }
533
534 if (cache() != nullptr) {
535 // cache() is null if this class is not yet linked.
536 cache()->remove_unshareable_info();
537 }
538 }
539
540 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
541 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
542 assert(tag_at(cp_index).is_klass(), "must be resolved");
543
544 bool can_archive;
545 Klass* k = nullptr;
546
547 if (CDSConfig::is_dumping_preimage_static_archive()) {
548 can_archive = false;
549 } else {
550 k = resolved_klass_at(cp_index);
551 if (k == nullptr) {
552 // We'd come here if the referenced class has been excluded via
553 // SystemDictionaryShared::is_excluded_class(). As a result, ArchiveBuilder
554 // has cleared the resolved_klasses()->at(...) pointer to null. Thus, we
555 // need to revert the tag to JVM_CONSTANT_UnresolvedClass.
556 can_archive = false;
557 } else {
558 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
559 can_archive = AOTConstantPoolResolver::is_resolution_deterministic(src_cp, cp_index);
560 }
561 }
562
563 if (!can_archive) {
564 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
565 // This might be at a safepoint but do this in the right order.
566 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
567 resolved_klasses()->at_put(resolved_klass_index, nullptr);
568 }
569
570 LogStreamHandle(Trace, aot, resolve) log;
571 if (log.is_enabled()) {
572 ResourceMark rm;
573 log.print("%s klass CP entry [%3d]: %s %s",
574 (can_archive ? "archived" : "reverted"),
575 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
576 if (can_archive) {
577 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
578 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
579 } else {
580 Symbol* name = klass_name_at(cp_index);
581 log.print(" => %s", name->as_C_string());
582 }
583 }
584
585 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(can_archive, /*reverted=*/!can_archive);
586 }
587 #endif // INCLUDE_CDS
588
589 int ConstantPool::cp_to_object_index(int cp_index) {
590 // this is harder don't do this so much.
591 int i = reference_map()->find(checked_cast<u2>(cp_index));
592 // We might not find the index for jsr292 call.
593 return (i < 0) ? _no_index_sentinel : i;
594 }
595
596 void ConstantPool::string_at_put(int obj_index, oop str) {
597 oop result = set_resolved_reference_at(obj_index, str);
598 assert(result == nullptr || result == str, "Only set once or to the same string.");
599 }
600
601 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
602 ResourceMark rm;
603 int line_number = -1;
604 const char * source_file = nullptr;
605 if (JavaThread::current()->has_last_Java_frame()) {
606 // try to identify the method which called this function.
607 vframeStream vfst(JavaThread::current());
608 if (!vfst.at_end()) {
609 line_number = vfst.method()->line_number_from_bci(vfst.bci());
610 Symbol* s = vfst.method()->method_holder()->source_file_name();
611 if (s != nullptr) {
612 source_file = s->as_C_string();
613 }
614 }
615 }
616 if (k != this_cp->pool_holder()) {
617 // only print something if the classes are different
618 if (source_file != nullptr) {
619 log_debug(class, resolve)("%s %s %s:%d",
620 this_cp->pool_holder()->external_name(),
621 k->external_name(), source_file, line_number);
622 } else {
623 log_debug(class, resolve)("%s %s",
624 this_cp->pool_holder()->external_name(),
625 k->external_name());
626 }
627 }
628 }
629
630 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
631 TRAPS) {
632 JavaThread* javaThread = THREAD;
633
634 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
635 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
636 // the entry and tag is not updated atomically.
637 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
638 int resolved_klass_index = kslot.resolved_klass_index();
639 int name_index = kslot.name_index();
640 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
641
642 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
643 // the unresolved_klasses() array.
644 if (this_cp->tag_at(cp_index).is_klass()) {
645 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
646 assert(klass != nullptr, "must be resolved");
647 return klass;
648 }
649
650 // This tag doesn't change back to unresolved class unless at a safepoint.
651 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
652 // The original attempt to resolve this constant pool entry failed so find the
653 // class of the original error and throw another error of the same class
654 // (JVMS 5.4.3).
655 // If there is a detail message, pass that detail message to the error.
656 // The JVMS does not strictly require us to duplicate the same detail message,
657 // or any internal exception fields such as cause or stacktrace. But since the
658 // detail message is often a class name or other literal string, we will repeat it
659 // if we can find it in the symbol table.
660 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
661 ShouldNotReachHere();
662 }
663
664 HandleMark hm(THREAD);
665 Handle mirror_handle;
666 Symbol* name = this_cp->symbol_at(name_index);
667 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
668
669 Klass* k;
670 {
671 // Turn off the single stepping while doing class resolution
672 JvmtiHideSingleStepping jhss(javaThread);
673 k = SystemDictionary::resolve_or_fail(name, loader, true, THREAD);
674 } // JvmtiHideSingleStepping jhss(javaThread);
675
676 if (!HAS_PENDING_EXCEPTION) {
677 // preserve the resolved klass from unloading
678 mirror_handle = Handle(THREAD, k->java_mirror());
679 // Do access check for klasses
680 verify_constant_pool_resolve(this_cp, k, THREAD);
681 }
682
683 #ifdef DEBUG
684 if (!HAS_PENDING_EXCEPTION && k->is_objArray_klass()) {
685 Klass* bottom_klass = ObjArrayKlass::cast(k)->bottom_klass();
686 assert(bottom_klass != nullptr, "Should be set");
687 assert(bottom_klass->is_instance_klass() || bottom_klass->is_typeArray_klass(), "Sanity check");
688 }
689 #endif
690
691 // Failed to resolve class. We must record the errors so that subsequent attempts
692 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
693 if (HAS_PENDING_EXCEPTION) {
694 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
695 // If CHECK_NULL above doesn't return the exception, that means that
696 // some other thread has beaten us and has resolved the class.
697 // To preserve old behavior, we return the resolved class.
698 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
699 assert(klass != nullptr, "must be resolved if exception was cleared");
700 return klass;
701 }
702
703 // logging for class+resolve.
704 if (log_is_enabled(Debug, class, resolve)){
705 trace_class_resolution(this_cp, k);
706 }
707
708 // The interpreter assumes when the tag is stored, the klass is resolved
709 // and the Klass* stored in _resolved_klasses is non-null, so we need
710 // hardware store ordering here.
711 // We also need to CAS to not overwrite an error from a racing thread.
712 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
713 AtomicAccess::release_store(adr, k);
714
715 jbyte old_tag = AtomicAccess::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
716 (jbyte)JVM_CONSTANT_UnresolvedClass,
717 (jbyte)JVM_CONSTANT_Class);
718
719 // We need to recheck exceptions from racing thread and return the same.
720 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
721 // Remove klass.
722 AtomicAccess::store(adr, (Klass*)nullptr);
723 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
724 }
725
726 return k;
727 }
728
729
730 // Does not update ConstantPool* - to avoid any exception throwing. Used
731 // by compiler and exception handling. Also used to avoid classloads for
732 // instanceof operations. Returns null if the class has not been loaded or
733 // if the verification of constant pool failed
734 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
735 CPKlassSlot kslot = this_cp->klass_slot_at(which);
736 int resolved_klass_index = kslot.resolved_klass_index();
737 int name_index = kslot.name_index();
738 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
739
740 if (this_cp->tag_at(which).is_klass()) {
741 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
742 assert(k != nullptr, "must be resolved");
743 return k;
744 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
745 return nullptr;
746 } else {
747 Thread* current = Thread::current();
748 HandleMark hm(current);
749 Symbol* name = this_cp->symbol_at(name_index);
750 oop loader = this_cp->pool_holder()->class_loader();
751 Handle h_loader (current, loader);
752 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader);
753
754 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
755 if (k != nullptr && current->is_Java_thread()) {
756 // Make sure that resolving is legal
757 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
758 ExceptionMark em(THREAD);
759 // return null if verification fails
760 verify_constant_pool_resolve(this_cp, k, THREAD);
761 if (HAS_PENDING_EXCEPTION) {
762 CLEAR_PENDING_EXCEPTION;
763 return nullptr;
764 }
765 return k;
766 } else {
767 return k;
768 }
769 }
770 }
771
772 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
773 int which) {
774 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
775 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
776 // FIXME: should be an assert
777 log_debug(class, resolve)("bad BSM %d in:", which); cpool->print();
778 return nullptr;
779 }
780 return cpool->cache()->method_if_resolved(which);
781 }
782
783
784 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
785 if (cpool->cache() == nullptr) return false; // nothing to load yet
786 if (code == Bytecodes::_invokedynamic) {
787 return cpool->resolved_indy_entry_at(which)->has_appendix();
788 } else {
789 return cpool->resolved_method_entry_at(which)->has_appendix();
790 }
791 }
792
793 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
794 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
795 if (code == Bytecodes::_invokedynamic) {
796 return cpool->resolved_reference_from_indy(which);
797 } else {
798 return cpool->cache()->appendix_if_resolved(which);
799 }
800 }
801
802
803 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
804 if (cpool->cache() == nullptr) return false; // nothing to load yet
805 if (code == Bytecodes::_invokedynamic) {
806 return cpool->resolved_indy_entry_at(which)->has_local_signature();
807 } else {
808 return cpool->resolved_method_entry_at(which)->has_local_signature();
809 }
810 }
811
812 // Translate index, which could be CPCache index or Indy index, to a constant pool index
813 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
814 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
815 switch(code) {
816 case Bytecodes::_invokedynamic:
817 return invokedynamic_bootstrap_ref_index_at(index);
818 case Bytecodes::_getfield:
819 case Bytecodes::_getstatic:
820 case Bytecodes::_putfield:
821 case Bytecodes::_putstatic:
822 return resolved_field_entry_at(index)->constant_pool_index();
823 case Bytecodes::_invokeinterface:
824 case Bytecodes::_invokehandle:
825 case Bytecodes::_invokespecial:
826 case Bytecodes::_invokestatic:
827 case Bytecodes::_invokevirtual:
828 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
829 return resolved_method_entry_at(index)->constant_pool_index();
830 default:
831 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
832 }
833 }
834
835 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
836 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
837 switch(code) {
838 case Bytecodes::_invokedynamic:
839 return resolved_indy_entry_at(index)->is_resolved();
840
841 case Bytecodes::_getfield:
842 case Bytecodes::_getstatic:
843 case Bytecodes::_putfield:
844 case Bytecodes::_putstatic:
845 return resolved_field_entry_at(index)->is_resolved(code);
846
847 case Bytecodes::_invokeinterface:
848 case Bytecodes::_invokehandle:
849 case Bytecodes::_invokespecial:
850 case Bytecodes::_invokestatic:
851 case Bytecodes::_invokevirtual:
852 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
853 return resolved_method_entry_at(index)->is_resolved(code);
854
855 default:
856 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
857 }
858 }
859
860 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
861 if (tag_at(cp_index).has_bootstrap()) {
862 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
863 assert(tag_at(pool_index).is_name_and_type(), "");
864 return pool_index;
865 }
866 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
867 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
868 jint ref_index = *int_at_addr(cp_index);
869 return extract_high_short_from_int(ref_index);
870 }
871
872 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
873 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
874 }
875
876 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
877 // which may be either a Constant Pool index or a rewritten index
878 int pool_index = which;
879 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
880 pool_index = to_cp_index(which, code);
881 return tag_at(pool_index);
882 }
883
884 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
885 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
886 jint ref_index = *int_at_addr(cp_index);
887 return extract_low_short_from_int(ref_index);
888 }
889
890 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
891 assert(code != Bytecodes::_invokedynamic,
892 "an invokedynamic instruction does not have a klass");
893 return uncached_klass_ref_index_at(to_cp_index(index, code));
894 }
895
896 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
897 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
898 return; // short cut, typeArray klass is always accessible
899 }
900 Klass* holder = this_cp->pool_holder();
901 LinkResolver::check_klass_accessibility(holder, k, CHECK);
902 }
903
904
905 u2 ConstantPool::name_ref_index_at(int cp_index) {
906 jint ref_index = name_and_type_at(cp_index);
907 return extract_low_short_from_int(ref_index);
908 }
909
910
911 u2 ConstantPool::signature_ref_index_at(int cp_index) {
912 jint ref_index = name_and_type_at(cp_index);
913 return extract_high_short_from_int(ref_index);
914 }
915
916
917 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
918 return klass_at(klass_ref_index_at(which, code), THREAD);
919 }
920
921 Symbol* ConstantPool::klass_name_at(int cp_index) const {
922 return symbol_at(klass_slot_at(cp_index).name_index());
923 }
924
925 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
926 jint ref_index = klass_ref_index_at(which, code);
927 return klass_at_noresolve(ref_index);
928 }
929
930 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
931 jint ref_index = uncached_klass_ref_index_at(cp_index);
932 return klass_at_noresolve(ref_index);
933 }
934
935 char* ConstantPool::string_at_noresolve(int cp_index) {
936 return unresolved_string_at(cp_index)->as_C_string();
937 }
938
939 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
940 return Signature::basic_type(symbol_at(cp_index));
941 }
942
943
944 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
945 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
946 if (this_cp->tag_at(index).is_string()) {
947 this_cp->string_at(index, CHECK);
948 }
949 }
950 }
951
952 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
953 // Note: caller needs ResourceMark
954
955 // Dig out the detailed message to reuse if possible
956 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
957 if (msg != nullptr) {
958 return msg;
959 }
960
961 Symbol* message = nullptr;
962 // Return specific message for the tag
963 switch (tag.value()) {
964 case JVM_CONSTANT_UnresolvedClass:
965 // return the class name in the error message
966 message = this_cp->klass_name_at(which);
967 break;
968 case JVM_CONSTANT_MethodHandle:
969 // return the method handle name in the error message
970 message = this_cp->method_handle_name_ref_at(which);
971 break;
972 case JVM_CONSTANT_MethodType:
973 // return the method type signature in the error message
974 message = this_cp->method_type_signature_at(which);
975 break;
976 case JVM_CONSTANT_Dynamic:
977 // return the name of the condy in the error message
978 message = this_cp->uncached_name_ref_at(which);
979 break;
980 default:
981 ShouldNotReachHere();
982 }
983
984 return message != nullptr ? message->as_C_string() : nullptr;
985 }
986
987 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
988 constantTag tag, oop pending_exception) {
989
990 ResourceMark rm(current);
991 Symbol* error = pending_exception->klass()->name();
992 oop cause = java_lang_Throwable::cause(pending_exception);
993
994 // Also dig out the exception cause, if present.
995 Symbol* cause_sym = nullptr;
996 const char* cause_msg = nullptr;
997 if (cause != nullptr && cause != pending_exception) {
998 cause_sym = cause->klass()->name();
999 cause_msg = java_lang_Throwable::message_as_utf8(cause);
1000 }
1001
1002 const char* message = exception_message(this_cp, which, tag, pending_exception);
1003 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1004 }
1005
1006
1007 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1008 ResourceMark rm(THREAD);
1009 const char* message = nullptr;
1010 Symbol* cause = nullptr;
1011 const char* cause_msg = nullptr;
1012 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1013 assert(error != nullptr, "checking");
1014
1015 CLEAR_PENDING_EXCEPTION;
1016 if (message != nullptr) {
1017 if (cause != nullptr) {
1018 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1019 THROW_MSG_CAUSE(error, message, h_cause);
1020 } else {
1021 THROW_MSG(error, message);
1022 }
1023 } else {
1024 if (cause != nullptr) {
1025 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1026 THROW_CAUSE(error, h_cause);
1027 } else {
1028 THROW(error);
1029 }
1030 }
1031 }
1032
1033 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1034 // exception in the resolution error table, so that the same exception is thrown again.
1035 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1036 constantTag tag, TRAPS) {
1037
1038 int error_tag = tag.error_value();
1039
1040 if (!PENDING_EXCEPTION->
1041 is_a(vmClasses::LinkageError_klass())) {
1042 // Just throw the exception and don't prevent these classes from
1043 // being loaded due to virtual machine errors like StackOverflow
1044 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1045 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1046 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1047 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1048 // CAS in the tag. If a thread beat us to registering this error that's fine.
1049 // If another thread resolved the reference, this is a race condition. This
1050 // thread may have had a security manager or something temporary.
1051 // This doesn't deterministically get an error. So why do we save this?
1052 // We save this because jvmti can add classes to the bootclass path after
1053 // this error, so it needs to get the same error if the error is first.
1054 jbyte old_tag = AtomicAccess::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1055 (jbyte)tag.value(),
1056 (jbyte)error_tag);
1057 if (old_tag != error_tag && old_tag != tag.value()) {
1058 // MethodHandles and MethodType doesn't change to resolved version.
1059 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1060 // Forget the exception and use the resolved class.
1061 CLEAR_PENDING_EXCEPTION;
1062 }
1063 } else {
1064 // some other thread put this in error state
1065 throw_resolution_error(this_cp, cp_index, CHECK);
1066 }
1067 }
1068
1069 constantTag ConstantPool::constant_tag_at(int cp_index) {
1070 constantTag tag = tag_at(cp_index);
1071 if (tag.is_dynamic_constant()) {
1072 BasicType bt = basic_type_for_constant_at(cp_index);
1073 return constantTag(constantTag::type2tag(bt));
1074 }
1075 return tag;
1076 }
1077
1078 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1079 constantTag tag = tag_at(cp_index);
1080 if (tag.is_dynamic_constant() ||
1081 tag.is_dynamic_constant_in_error()) {
1082 // have to look at the signature for this one
1083 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1084 return Signature::basic_type(constant_type);
1085 }
1086 return tag.basic_type();
1087 }
1088
1089 // Called to resolve constants in the constant pool and return an oop.
1090 // Some constant pool entries cache their resolved oop. This is also
1091 // called to create oops from constants to use in arguments for invokedynamic
1092 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1093 int cp_index, int cache_index,
1094 bool* status_return, TRAPS) {
1095 oop result_oop = nullptr;
1096
1097 if (cache_index == _possible_index_sentinel) {
1098 // It is possible that this constant is one which is cached in the objects.
1099 // We'll do a linear search. This should be OK because this usage is rare.
1100 // FIXME: If bootstrap specifiers stress this code, consider putting in
1101 // a reverse index. Binary search over a short array should do it.
1102 assert(cp_index > 0, "valid constant pool index");
1103 cache_index = this_cp->cp_to_object_index(cp_index);
1104 }
1105 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1106 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1107
1108 if (cache_index >= 0) {
1109 result_oop = this_cp->resolved_reference_at(cache_index);
1110 if (result_oop != nullptr) {
1111 if (result_oop == Universe::the_null_sentinel()) {
1112 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1113 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1114 result_oop = nullptr;
1115 }
1116 if (status_return != nullptr) (*status_return) = true;
1117 return result_oop;
1118 // That was easy...
1119 }
1120 cp_index = this_cp->object_to_cp_index(cache_index);
1121 }
1122
1123 jvalue prim_value; // temp used only in a few cases below
1124
1125 constantTag tag = this_cp->tag_at(cp_index);
1126
1127 if (status_return != nullptr) {
1128 // don't trigger resolution if the constant might need it
1129 switch (tag.value()) {
1130 case JVM_CONSTANT_Class:
1131 assert(this_cp->resolved_klass_at(cp_index) != nullptr, "must be resolved");
1132 break;
1133 case JVM_CONSTANT_String:
1134 case JVM_CONSTANT_Integer:
1135 case JVM_CONSTANT_Float:
1136 case JVM_CONSTANT_Long:
1137 case JVM_CONSTANT_Double:
1138 // these guys trigger OOM at worst
1139 break;
1140 default:
1141 (*status_return) = false;
1142 return nullptr;
1143 }
1144 // from now on there is either success or an OOME
1145 (*status_return) = true;
1146 }
1147
1148 switch (tag.value()) {
1149
1150 case JVM_CONSTANT_UnresolvedClass:
1151 case JVM_CONSTANT_Class:
1152 {
1153 assert(cache_index == _no_index_sentinel, "should not have been set");
1154 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1155 // ldc wants the java mirror.
1156 result_oop = resolved->java_mirror();
1157 break;
1158 }
1159
1160 case JVM_CONSTANT_Dynamic:
1161 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1162 ClassLoader::perf_resolve_invokedynamic_count());
1163
1164 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1165 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1166
1167 // The initial step in resolving an unresolved symbolic reference to a
1168 // dynamically-computed constant is to resolve the symbolic reference to a
1169 // method handle which will be the bootstrap method for the dynamically-computed
1170 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1171 // method fails, then a MethodHandleInError is stored at the corresponding
1172 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1173 // set a DynamicConstantInError here since any subsequent use of this
1174 // bootstrap method will encounter the resolution of MethodHandleInError.
1175 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1176 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1177 // for the bootstrap_specifier created above.
1178 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1179 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1180 if (HAS_PENDING_EXCEPTION) {
1181 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1182 // will check for a LinkageError and store a DynamicConstantInError.
1183 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1184 }
1185 result_oop = bootstrap_specifier.resolved_value()();
1186 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1187 if (!is_reference_type(type)) {
1188 // Make sure the primitive value is properly boxed.
1189 // This is a JDK responsibility.
1190 const char* fail = nullptr;
1191 if (result_oop == nullptr) {
1192 fail = "null result instead of box";
1193 } else if (!is_java_primitive(type)) {
1194 // FIXME: support value types via unboxing
1195 fail = "can only handle references and primitives";
1196 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1197 fail = "primitive is not properly boxed";
1198 }
1199 if (fail != nullptr) {
1200 // Since this exception is not a LinkageError, throw exception
1201 // but do not save a DynamicInError resolution result.
1202 // See section 5.4.3 of the VM spec.
1203 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1204 }
1205 }
1206
1207 LogTarget(Debug, methodhandles, condy) lt_condy;
1208 if (lt_condy.is_enabled()) {
1209 LogStream ls(lt_condy);
1210 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1211 }
1212 break;
1213 }
1214
1215 case JVM_CONSTANT_String:
1216 assert(cache_index != _no_index_sentinel, "should have been set");
1217 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1218 break;
1219
1220 case JVM_CONSTANT_MethodHandle:
1221 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1222 ClassLoader::perf_resolve_method_handle_count());
1223
1224 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1225 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1226 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1227 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1228 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1229 { ResourceMark rm(THREAD);
1230 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1231 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1232 callee_index, name->as_C_string(), signature->as_C_string());
1233 }
1234
1235 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1236 if (HAS_PENDING_EXCEPTION) {
1237 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1238 }
1239
1240 // Check constant pool method consistency
1241 if ((callee->is_interface() && m_tag.is_method()) ||
1242 (!callee->is_interface() && m_tag.is_interface_method())) {
1243 ResourceMark rm(THREAD);
1244 stringStream ss;
1245 ss.print("Inconsistent constant pool data in classfile for class %s. "
1246 "Method '", callee->name()->as_C_string());
1247 signature->print_as_signature_external_return_type(&ss);
1248 ss.print(" %s(", name->as_C_string());
1249 signature->print_as_signature_external_parameters(&ss);
1250 ss.print(")' at index %d is %s and should be %s",
1251 cp_index,
1252 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1253 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1254 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1255 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1256 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1257 }
1258
1259 Klass* klass = this_cp->pool_holder();
1260 HandleMark hm(THREAD);
1261 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1262 callee, name, signature,
1263 THREAD);
1264 if (HAS_PENDING_EXCEPTION) {
1265 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1266 }
1267 result_oop = value();
1268 break;
1269 }
1270
1271 case JVM_CONSTANT_MethodType:
1272 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1273 ClassLoader::perf_resolve_method_type_count());
1274
1275 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1276 { ResourceMark rm(THREAD);
1277 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1278 cp_index, this_cp->method_type_index_at(cp_index),
1279 signature->as_C_string());
1280 }
1281 Klass* klass = this_cp->pool_holder();
1282 HandleMark hm(THREAD);
1283 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1284 result_oop = value();
1285 if (HAS_PENDING_EXCEPTION) {
1286 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1287 }
1288 break;
1289 }
1290
1291 case JVM_CONSTANT_Integer:
1292 assert(cache_index == _no_index_sentinel, "should not have been set");
1293 prim_value.i = this_cp->int_at(cp_index);
1294 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1295 break;
1296
1297 case JVM_CONSTANT_Float:
1298 assert(cache_index == _no_index_sentinel, "should not have been set");
1299 prim_value.f = this_cp->float_at(cp_index);
1300 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1301 break;
1302
1303 case JVM_CONSTANT_Long:
1304 assert(cache_index == _no_index_sentinel, "should not have been set");
1305 prim_value.j = this_cp->long_at(cp_index);
1306 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1307 break;
1308
1309 case JVM_CONSTANT_Double:
1310 assert(cache_index == _no_index_sentinel, "should not have been set");
1311 prim_value.d = this_cp->double_at(cp_index);
1312 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1313 break;
1314
1315 case JVM_CONSTANT_UnresolvedClassInError:
1316 case JVM_CONSTANT_DynamicInError:
1317 case JVM_CONSTANT_MethodHandleInError:
1318 case JVM_CONSTANT_MethodTypeInError:
1319 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1320 break;
1321
1322 default:
1323 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1324 break;
1325 }
1326
1327 if (cache_index >= 0) {
1328 // Benign race condition: resolved_references may already be filled in.
1329 // The important thing here is that all threads pick up the same result.
1330 // It doesn't matter which racing thread wins, as long as only one
1331 // result is used by all threads, and all future queries.
1332 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1333 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1334 if (old_result == nullptr) {
1335 return result_oop; // was installed
1336 } else {
1337 // Return the winning thread's result. This can be different than
1338 // the result here for MethodHandles.
1339 if (old_result == Universe::the_null_sentinel())
1340 old_result = nullptr;
1341 return old_result;
1342 }
1343 } else {
1344 assert(result_oop != Universe::the_null_sentinel(), "");
1345 return result_oop;
1346 }
1347 }
1348
1349 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1350 Symbol* sym = unresolved_string_at(cp_index);
1351 oop str = StringTable::intern(sym, CHECK_(nullptr));
1352 assert(java_lang_String::is_instance(str), "must be string");
1353 return str;
1354 }
1355
1356 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1357 int start_arg, int end_arg,
1358 refArrayHandle info, int pos,
1359 bool must_resolve, Handle if_not_available,
1360 TRAPS) {
1361 int limit = pos + end_arg - start_arg;
1362 // checks: cp_index in range [0..this_cp->length),
1363 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1364 // info array non-null, pos..limit in [0..info.length]
1365 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1366 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1367 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1368 (0 > start_arg || start_arg > end_arg) ||
1369 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1370 (0 > pos || pos > limit) ||
1371 (info.is_null() || limit > info->length())) {
1372 // An index or something else went wrong; throw an error.
1373 // Since this is an internal API, we don't expect this,
1374 // so we don't bother to craft a nice message.
1375 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1376 }
1377 // now we can loop safely
1378 int info_i = pos;
1379 for (int i = start_arg; i < end_arg; i++) {
1380 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1381 oop arg_oop;
1382 if (must_resolve) {
1383 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1384 } else {
1385 bool found_it = false;
1386 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1387 if (!found_it) arg_oop = if_not_available();
1388 }
1389 info->obj_at_put(info_i++, arg_oop);
1390 }
1391 }
1392
1393 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1394 // If the string has already been interned, this entry will be non-null
1395 oop str = this_cp->resolved_reference_at(obj_index);
1396 assert(str != Universe::the_null_sentinel(), "");
1397 if (str != nullptr) return str;
1398 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1399 str = StringTable::intern(sym, CHECK_(nullptr));
1400 this_cp->string_at_put(obj_index, str);
1401 assert(java_lang_String::is_instance(str), "must be string");
1402 return str;
1403 }
1404
1405
1406 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1407 // Names are interned, so we can compare Symbol*s directly
1408 Symbol* cp_name = klass_name_at(cp_index);
1409 return (cp_name == k->name());
1410 }
1411
1412
1413 // Iterate over symbols and decrement ones which are Symbol*s
1414 // This is done during GC.
1415 // Only decrement the UTF8 symbols. Strings point to
1416 // these symbols but didn't increment the reference count.
1417 void ConstantPool::unreference_symbols() {
1418 for (int index = 1; index < length(); index++) { // Index 0 is unused
1419 constantTag tag = tag_at(index);
1420 if (tag.is_symbol()) {
1421 symbol_at(index)->decrement_refcount();
1422 }
1423 }
1424 }
1425
1426
1427 // Compare this constant pool's entry at index1 to the constant pool
1428 // cp2's entry at index2.
1429 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1430 int index2) {
1431
1432 // The error tags are equivalent to non-error tags when comparing
1433 jbyte t1 = tag_at(index1).non_error_value();
1434 jbyte t2 = cp2->tag_at(index2).non_error_value();
1435
1436 // Some classes are pre-resolved (like Throwable) which may lead to
1437 // consider it as a different entry. We then revert them back temporarily
1438 // to ensure proper comparison.
1439 if (t1 == JVM_CONSTANT_Class) {
1440 t1 = JVM_CONSTANT_UnresolvedClass;
1441 }
1442 if (t2 == JVM_CONSTANT_Class) {
1443 t2 = JVM_CONSTANT_UnresolvedClass;
1444 }
1445
1446 if (t1 != t2) {
1447 // Not the same entry type so there is nothing else to check. Note
1448 // that this style of checking will consider resolved/unresolved
1449 // class pairs as different.
1450 // From the ConstantPool* API point of view, this is correct
1451 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1452 // plays out in the context of ConstantPool* merging.
1453 return false;
1454 }
1455
1456 switch (t1) {
1457 case JVM_CONSTANT_ClassIndex:
1458 {
1459 int recur1 = klass_index_at(index1);
1460 int recur2 = cp2->klass_index_at(index2);
1461 if (compare_entry_to(recur1, cp2, recur2)) {
1462 return true;
1463 }
1464 } break;
1465
1466 case JVM_CONSTANT_Double:
1467 {
1468 jdouble d1 = double_at(index1);
1469 jdouble d2 = cp2->double_at(index2);
1470 if (d1 == d2) {
1471 return true;
1472 }
1473 } break;
1474
1475 case JVM_CONSTANT_Fieldref:
1476 case JVM_CONSTANT_InterfaceMethodref:
1477 case JVM_CONSTANT_Methodref:
1478 {
1479 int recur1 = uncached_klass_ref_index_at(index1);
1480 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1481 bool match = compare_entry_to(recur1, cp2, recur2);
1482 if (match) {
1483 recur1 = uncached_name_and_type_ref_index_at(index1);
1484 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1485 if (compare_entry_to(recur1, cp2, recur2)) {
1486 return true;
1487 }
1488 }
1489 } break;
1490
1491 case JVM_CONSTANT_Float:
1492 {
1493 jfloat f1 = float_at(index1);
1494 jfloat f2 = cp2->float_at(index2);
1495 if (f1 == f2) {
1496 return true;
1497 }
1498 } break;
1499
1500 case JVM_CONSTANT_Integer:
1501 {
1502 jint i1 = int_at(index1);
1503 jint i2 = cp2->int_at(index2);
1504 if (i1 == i2) {
1505 return true;
1506 }
1507 } break;
1508
1509 case JVM_CONSTANT_Long:
1510 {
1511 jlong l1 = long_at(index1);
1512 jlong l2 = cp2->long_at(index2);
1513 if (l1 == l2) {
1514 return true;
1515 }
1516 } break;
1517
1518 case JVM_CONSTANT_NameAndType:
1519 {
1520 int recur1 = name_ref_index_at(index1);
1521 int recur2 = cp2->name_ref_index_at(index2);
1522 if (compare_entry_to(recur1, cp2, recur2)) {
1523 recur1 = signature_ref_index_at(index1);
1524 recur2 = cp2->signature_ref_index_at(index2);
1525 if (compare_entry_to(recur1, cp2, recur2)) {
1526 return true;
1527 }
1528 }
1529 } break;
1530
1531 case JVM_CONSTANT_StringIndex:
1532 {
1533 int recur1 = string_index_at(index1);
1534 int recur2 = cp2->string_index_at(index2);
1535 if (compare_entry_to(recur1, cp2, recur2)) {
1536 return true;
1537 }
1538 } break;
1539
1540 case JVM_CONSTANT_UnresolvedClass:
1541 {
1542 Symbol* k1 = klass_name_at(index1);
1543 Symbol* k2 = cp2->klass_name_at(index2);
1544 if (k1 == k2) {
1545 return true;
1546 }
1547 } break;
1548
1549 case JVM_CONSTANT_MethodType:
1550 {
1551 int k1 = method_type_index_at(index1);
1552 int k2 = cp2->method_type_index_at(index2);
1553 if (compare_entry_to(k1, cp2, k2)) {
1554 return true;
1555 }
1556 } break;
1557
1558 case JVM_CONSTANT_MethodHandle:
1559 {
1560 int k1 = method_handle_ref_kind_at(index1);
1561 int k2 = cp2->method_handle_ref_kind_at(index2);
1562 if (k1 == k2) {
1563 int i1 = method_handle_index_at(index1);
1564 int i2 = cp2->method_handle_index_at(index2);
1565 if (compare_entry_to(i1, cp2, i2)) {
1566 return true;
1567 }
1568 }
1569 } break;
1570
1571 case JVM_CONSTANT_Dynamic:
1572 {
1573 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1574 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1575 int i1 = bootstrap_methods_attribute_index(index1);
1576 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1577 bool match_entry = compare_entry_to(k1, cp2, k2);
1578 bool match_bsm = compare_bootstrap_entry_to(i1, cp2, i2);
1579 return (match_entry && match_bsm);
1580 } break;
1581
1582 case JVM_CONSTANT_InvokeDynamic:
1583 {
1584 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1585 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1586 int i1 = bootstrap_methods_attribute_index(index1);
1587 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1588 bool match_entry = compare_entry_to(k1, cp2, k2);
1589 bool match_bsm = compare_bootstrap_entry_to(i1, cp2, i2);
1590 return (match_entry && match_bsm);
1591 } break;
1592
1593 case JVM_CONSTANT_String:
1594 {
1595 Symbol* s1 = unresolved_string_at(index1);
1596 Symbol* s2 = cp2->unresolved_string_at(index2);
1597 if (s1 == s2) {
1598 return true;
1599 }
1600 } break;
1601
1602 case JVM_CONSTANT_Utf8:
1603 {
1604 Symbol* s1 = symbol_at(index1);
1605 Symbol* s2 = cp2->symbol_at(index2);
1606 if (s1 == s2) {
1607 return true;
1608 }
1609 } break;
1610
1611 // Invalid is used as the tag for the second constant pool entry
1612 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1613 // not be seen by itself.
1614 case JVM_CONSTANT_Invalid: // fall through
1615
1616 default:
1617 ShouldNotReachHere();
1618 break;
1619 }
1620
1621 return false;
1622 } // end compare_entry_to()
1623
1624 // Extend the BSMAttributeEntries with the length and size of the ext_cp BSMAttributeEntries.
1625 // Used in RedefineClasses for CP merge.
1626 BSMAttributeEntries::InsertionIterator
1627 ConstantPool::start_extension(const constantPoolHandle& ext_cp, TRAPS) {
1628 BSMAttributeEntries::InsertionIterator iter =
1629 bsm_entries().start_extension(ext_cp->bsm_entries(), pool_holder()->class_loader_data(),
1630 CHECK_(BSMAttributeEntries::InsertionIterator()));
1631 return iter;
1632 }
1633
1634
1635 void ConstantPool::end_extension(BSMAttributeEntries::InsertionIterator iter, TRAPS) {
1636 bsm_entries().end_extension(iter, pool_holder()->class_loader_data(), THREAD);
1637 }
1638
1639
1640 void ConstantPool::copy_bsm_entries(const constantPoolHandle& from_cp,
1641 const constantPoolHandle& to_cp,
1642 TRAPS) {
1643 to_cp->bsm_entries().append(from_cp->bsm_entries(),
1644 to_cp->pool_holder()->class_loader_data(),
1645 THREAD);
1646 }
1647
1648
1649 // Copy this constant pool's entries at start_i to end_i (inclusive)
1650 // to the constant pool to_cp's entries starting at to_i. A total of
1651 // (end_i - start_i) + 1 entries are copied.
1652 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1653 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1654
1655
1656 int dest_cpi = to_i; // leave original alone for debug purposes
1657
1658 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1659 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1660
1661 switch (from_cp->tag_at(src_cpi).value()) {
1662 case JVM_CONSTANT_Double:
1663 case JVM_CONSTANT_Long:
1664 // double and long take two constant pool entries
1665 src_cpi += 2;
1666 dest_cpi += 2;
1667 break;
1668
1669 default:
1670 // all others take one constant pool entry
1671 src_cpi++;
1672 dest_cpi++;
1673 break;
1674 }
1675 }
1676 copy_bsm_entries(from_cp, to_cp, THREAD);
1677
1678 } // end copy_cp_to_impl()
1679
1680
1681 // Copy this constant pool's entry at from_i to the constant pool
1682 // to_cp's entry at to_i.
1683 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1684 const constantPoolHandle& to_cp, int to_i) {
1685
1686 int tag = from_cp->tag_at(from_i).value();
1687 switch (tag) {
1688 case JVM_CONSTANT_ClassIndex:
1689 {
1690 jint ki = from_cp->klass_index_at(from_i);
1691 to_cp->klass_index_at_put(to_i, ki);
1692 } break;
1693
1694 case JVM_CONSTANT_Double:
1695 {
1696 jdouble d = from_cp->double_at(from_i);
1697 to_cp->double_at_put(to_i, d);
1698 // double takes two constant pool entries so init second entry's tag
1699 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1700 } break;
1701
1702 case JVM_CONSTANT_Fieldref:
1703 {
1704 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1705 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1706 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1707 } break;
1708
1709 case JVM_CONSTANT_Float:
1710 {
1711 jfloat f = from_cp->float_at(from_i);
1712 to_cp->float_at_put(to_i, f);
1713 } break;
1714
1715 case JVM_CONSTANT_Integer:
1716 {
1717 jint i = from_cp->int_at(from_i);
1718 to_cp->int_at_put(to_i, i);
1719 } break;
1720
1721 case JVM_CONSTANT_InterfaceMethodref:
1722 {
1723 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1724 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1725 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1726 } break;
1727
1728 case JVM_CONSTANT_Long:
1729 {
1730 jlong l = from_cp->long_at(from_i);
1731 to_cp->long_at_put(to_i, l);
1732 // long takes two constant pool entries so init second entry's tag
1733 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1734 } break;
1735
1736 case JVM_CONSTANT_Methodref:
1737 {
1738 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1739 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1740 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1741 } break;
1742
1743 case JVM_CONSTANT_NameAndType:
1744 {
1745 int name_ref_index = from_cp->name_ref_index_at(from_i);
1746 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1747 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1748 } break;
1749
1750 case JVM_CONSTANT_StringIndex:
1751 {
1752 jint si = from_cp->string_index_at(from_i);
1753 to_cp->string_index_at_put(to_i, si);
1754 } break;
1755
1756 case JVM_CONSTANT_Class:
1757 case JVM_CONSTANT_UnresolvedClass:
1758 case JVM_CONSTANT_UnresolvedClassInError:
1759 {
1760 // Revert to JVM_CONSTANT_ClassIndex
1761 int name_index = from_cp->klass_slot_at(from_i).name_index();
1762 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1763 to_cp->klass_index_at_put(to_i, name_index);
1764 } break;
1765
1766 case JVM_CONSTANT_String:
1767 {
1768 Symbol* s = from_cp->unresolved_string_at(from_i);
1769 to_cp->unresolved_string_at_put(to_i, s);
1770 } break;
1771
1772 case JVM_CONSTANT_Utf8:
1773 {
1774 Symbol* s = from_cp->symbol_at(from_i);
1775 // Need to increase refcount, the old one will be thrown away and deferenced
1776 s->increment_refcount();
1777 to_cp->symbol_at_put(to_i, s);
1778 } break;
1779
1780 case JVM_CONSTANT_MethodType:
1781 case JVM_CONSTANT_MethodTypeInError:
1782 {
1783 jint k = from_cp->method_type_index_at(from_i);
1784 to_cp->method_type_index_at_put(to_i, k);
1785 } break;
1786
1787 case JVM_CONSTANT_MethodHandle:
1788 case JVM_CONSTANT_MethodHandleInError:
1789 {
1790 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1791 int k2 = from_cp->method_handle_index_at(from_i);
1792 to_cp->method_handle_index_at_put(to_i, k1, k2);
1793 } break;
1794
1795 case JVM_CONSTANT_Dynamic:
1796 case JVM_CONSTANT_DynamicInError:
1797 {
1798 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1799 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1800 k1 += to_cp->bsm_entries().array_length(); // to_cp might already have a BSM attribute
1801 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1802 } break;
1803
1804 case JVM_CONSTANT_InvokeDynamic:
1805 {
1806 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1807 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1808 k1 += to_cp->bsm_entries().array_length(); // to_cp might already have a BSM attribute
1809 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1810 } break;
1811
1812 // Invalid is used as the tag for the second constant pool entry
1813 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1814 // not be seen by itself.
1815 case JVM_CONSTANT_Invalid: // fall through
1816
1817 default:
1818 {
1819 ShouldNotReachHere();
1820 } break;
1821 }
1822 } // end copy_entry_to()
1823
1824 // Search constant pool search_cp for an entry that matches this
1825 // constant pool's entry at pattern_i. Returns the index of a
1826 // matching entry or zero (0) if there is no matching entry.
1827 int ConstantPool::find_matching_entry(int pattern_i,
1828 const constantPoolHandle& search_cp) {
1829
1830 // index zero (0) is not used
1831 for (int i = 1; i < search_cp->length(); i++) {
1832 bool found = compare_entry_to(pattern_i, search_cp, i);
1833 if (found) {
1834 return i;
1835 }
1836 }
1837
1838 return 0; // entry not found; return unused index zero (0)
1839 } // end find_matching_entry()
1840
1841
1842 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1843 // cp2's bootstrap specifier at idx2.
1844 bool ConstantPool::compare_bootstrap_entry_to(int idx1, const constantPoolHandle& cp2, int idx2) {
1845 const BSMAttributeEntry* const e1 = bsm_attribute_entry(idx1);
1846 const BSMAttributeEntry* const e2 = cp2->bsm_attribute_entry(idx2);
1847 int k1 = e1->bootstrap_method_index();
1848 int k2 = e2->bootstrap_method_index();
1849 bool match = compare_entry_to(k1, cp2, k2);
1850
1851 if (!match) {
1852 return false;
1853 }
1854
1855 const int argc = e1->argument_count();
1856 if (argc != e2->argument_count()) {
1857 return false;
1858 }
1859
1860 for (int j = 0; j < argc; j++) {
1861 k1 = e1->argument(j);
1862 k2 = e2->argument(j);
1863 match = compare_entry_to(k1, cp2, k2);
1864 if (!match) {
1865 return false;
1866 }
1867 }
1868
1869 return true; // got through loop; all elements equal
1870 } // end compare_bootstrap_entry_to()
1871
1872 // Search constant pool search_cp for a bootstrap specifier that matches
1873 // this constant pool's bootstrap specifier data at pattern_i index.
1874 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
1875 int ConstantPool::find_matching_bsm_entry(int pattern_i,
1876 const constantPoolHandle& search_cp, int offset_limit) {
1877 for (int i = 0; i < offset_limit; i++) {
1878 bool found = compare_bootstrap_entry_to(pattern_i, search_cp, i);
1879 if (found) {
1880 return i;
1881 }
1882 }
1883 return -1; // bootstrap specifier data not found; return unused index (-1)
1884 } // end find_matching_bsm_entry()
1885
1886
1887 #ifndef PRODUCT
1888
1889 const char* ConstantPool::printable_name_at(int cp_index) {
1890
1891 constantTag tag = tag_at(cp_index);
1892
1893 if (tag.is_string()) {
1894 return string_at_noresolve(cp_index);
1895 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1896 return klass_name_at(cp_index)->as_C_string();
1897 } else if (tag.is_symbol()) {
1898 return symbol_at(cp_index)->as_C_string();
1899 }
1900 return "";
1901 }
1902
1903 #endif // PRODUCT
1904
1905
1906 // Returns size of constant pool entry.
1907 jint ConstantPool::cpool_entry_size(jint idx) {
1908 switch(tag_at(idx).value()) {
1909 case JVM_CONSTANT_Invalid:
1910 case JVM_CONSTANT_Unicode:
1911 return 1;
1912
1913 case JVM_CONSTANT_Utf8:
1914 return 3 + symbol_at(idx)->utf8_length();
1915
1916 case JVM_CONSTANT_Class:
1917 case JVM_CONSTANT_String:
1918 case JVM_CONSTANT_ClassIndex:
1919 case JVM_CONSTANT_UnresolvedClass:
1920 case JVM_CONSTANT_UnresolvedClassInError:
1921 case JVM_CONSTANT_StringIndex:
1922 case JVM_CONSTANT_MethodType:
1923 case JVM_CONSTANT_MethodTypeInError:
1924 return 3;
1925
1926 case JVM_CONSTANT_MethodHandle:
1927 case JVM_CONSTANT_MethodHandleInError:
1928 return 4; //tag, ref_kind, ref_index
1929
1930 case JVM_CONSTANT_Integer:
1931 case JVM_CONSTANT_Float:
1932 case JVM_CONSTANT_Fieldref:
1933 case JVM_CONSTANT_Methodref:
1934 case JVM_CONSTANT_InterfaceMethodref:
1935 case JVM_CONSTANT_NameAndType:
1936 return 5;
1937
1938 case JVM_CONSTANT_Dynamic:
1939 case JVM_CONSTANT_DynamicInError:
1940 case JVM_CONSTANT_InvokeDynamic:
1941 // u1 tag, u2 bsm, u2 nt
1942 return 5;
1943
1944 case JVM_CONSTANT_Long:
1945 case JVM_CONSTANT_Double:
1946 return 9;
1947 }
1948 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1949 return 1;
1950 } /* end cpool_entry_size */
1951
1952
1953 // SymbolHash is used to find a constant pool index from a string.
1954 // This function fills in SymbolHashs, one for utf8s and one for
1955 // class names, returns size of the cpool raw bytes.
1956 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
1957 SymbolHash *classmap) {
1958 jint size = 0;
1959
1960 for (u2 idx = 1; idx < length(); idx++) {
1961 u2 tag = tag_at(idx).value();
1962 size += cpool_entry_size(idx);
1963
1964 switch(tag) {
1965 case JVM_CONSTANT_Utf8: {
1966 Symbol* sym = symbol_at(idx);
1967 symmap->add_if_absent(sym, idx);
1968 break;
1969 }
1970 case JVM_CONSTANT_Class:
1971 case JVM_CONSTANT_UnresolvedClass:
1972 case JVM_CONSTANT_UnresolvedClassInError: {
1973 Symbol* sym = klass_name_at(idx);
1974 classmap->add_if_absent(sym, idx);
1975 break;
1976 }
1977 case JVM_CONSTANT_Long:
1978 case JVM_CONSTANT_Double: {
1979 idx++; // Both Long and Double take two cpool slots
1980 break;
1981 }
1982 }
1983 }
1984 return size;
1985 } /* end hash_utf8_entries_to */
1986
1987
1988 // Copy cpool bytes.
1989 // Returns:
1990 // 0, in case of OutOfMemoryError
1991 // -1, in case of internal error
1992 // > 0, count of the raw cpool bytes that have been copied
1993 int ConstantPool::copy_cpool_bytes(int cpool_size,
1994 SymbolHash* tbl,
1995 unsigned char *bytes) {
1996 u2 idx1, idx2;
1997 jint size = 0;
1998 jint cnt = length();
1999 unsigned char *start_bytes = bytes;
2000
2001 for (jint idx = 1; idx < cnt; idx++) {
2002 u1 tag = tag_at(idx).value();
2003 jint ent_size = cpool_entry_size(idx);
2004
2005 assert(size + ent_size <= cpool_size, "Size mismatch");
2006
2007 *bytes = tag;
2008 switch(tag) {
2009 case JVM_CONSTANT_Invalid: {
2010 break;
2011 }
2012 case JVM_CONSTANT_Unicode: {
2013 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2014 break;
2015 }
2016 case JVM_CONSTANT_Utf8: {
2017 Symbol* sym = symbol_at(idx);
2018 char* str = sym->as_utf8();
2019 // Warning! It's crashing on x86 with len = sym->utf8_length()
2020 int len = (int) strlen(str);
2021 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2022 for (int i = 0; i < len; i++) {
2023 bytes[3+i] = (u1) str[i];
2024 }
2025 break;
2026 }
2027 case JVM_CONSTANT_Integer: {
2028 jint val = int_at(idx);
2029 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2030 break;
2031 }
2032 case JVM_CONSTANT_Float: {
2033 jfloat val = float_at(idx);
2034 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2035 break;
2036 }
2037 case JVM_CONSTANT_Long: {
2038 jlong val = long_at(idx);
2039 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2040 idx++; // Long takes two cpool slots
2041 break;
2042 }
2043 case JVM_CONSTANT_Double: {
2044 jdouble val = double_at(idx);
2045 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2046 idx++; // Double takes two cpool slots
2047 break;
2048 }
2049 case JVM_CONSTANT_Class:
2050 case JVM_CONSTANT_UnresolvedClass:
2051 case JVM_CONSTANT_UnresolvedClassInError: {
2052 *bytes = JVM_CONSTANT_Class;
2053 Symbol* sym = klass_name_at(idx);
2054 idx1 = tbl->symbol_to_value(sym);
2055 assert(idx1 != 0, "Have not found a hashtable entry");
2056 Bytes::put_Java_u2((address) (bytes+1), idx1);
2057 break;
2058 }
2059 case JVM_CONSTANT_String: {
2060 *bytes = JVM_CONSTANT_String;
2061 Symbol* sym = unresolved_string_at(idx);
2062 idx1 = tbl->symbol_to_value(sym);
2063 assert(idx1 != 0, "Have not found a hashtable entry");
2064 Bytes::put_Java_u2((address) (bytes+1), idx1);
2065 break;
2066 }
2067 case JVM_CONSTANT_Fieldref:
2068 case JVM_CONSTANT_Methodref:
2069 case JVM_CONSTANT_InterfaceMethodref: {
2070 idx1 = uncached_klass_ref_index_at(idx);
2071 idx2 = uncached_name_and_type_ref_index_at(idx);
2072 Bytes::put_Java_u2((address) (bytes+1), idx1);
2073 Bytes::put_Java_u2((address) (bytes+3), idx2);
2074 break;
2075 }
2076 case JVM_CONSTANT_NameAndType: {
2077 idx1 = name_ref_index_at(idx);
2078 idx2 = signature_ref_index_at(idx);
2079 Bytes::put_Java_u2((address) (bytes+1), idx1);
2080 Bytes::put_Java_u2((address) (bytes+3), idx2);
2081 break;
2082 }
2083 case JVM_CONSTANT_ClassIndex: {
2084 *bytes = JVM_CONSTANT_Class;
2085 idx1 = checked_cast<u2>(klass_index_at(idx));
2086 Bytes::put_Java_u2((address) (bytes+1), idx1);
2087 break;
2088 }
2089 case JVM_CONSTANT_StringIndex: {
2090 *bytes = JVM_CONSTANT_String;
2091 idx1 = checked_cast<u2>(string_index_at(idx));
2092 Bytes::put_Java_u2((address) (bytes+1), idx1);
2093 break;
2094 }
2095 case JVM_CONSTANT_MethodHandle:
2096 case JVM_CONSTANT_MethodHandleInError: {
2097 *bytes = JVM_CONSTANT_MethodHandle;
2098 int kind = method_handle_ref_kind_at(idx);
2099 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2100 *(bytes+1) = (unsigned char) kind;
2101 Bytes::put_Java_u2((address) (bytes+2), idx1);
2102 break;
2103 }
2104 case JVM_CONSTANT_MethodType:
2105 case JVM_CONSTANT_MethodTypeInError: {
2106 *bytes = JVM_CONSTANT_MethodType;
2107 idx1 = checked_cast<u2>(method_type_index_at(idx));
2108 Bytes::put_Java_u2((address) (bytes+1), idx1);
2109 break;
2110 }
2111 case JVM_CONSTANT_Dynamic:
2112 case JVM_CONSTANT_DynamicInError: {
2113 *bytes = tag;
2114 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2115 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2116 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2117 Bytes::put_Java_u2((address) (bytes+1), idx1);
2118 Bytes::put_Java_u2((address) (bytes+3), idx2);
2119 break;
2120 }
2121 case JVM_CONSTANT_InvokeDynamic: {
2122 *bytes = tag;
2123 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2124 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2125 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2126 Bytes::put_Java_u2((address) (bytes+1), idx1);
2127 Bytes::put_Java_u2((address) (bytes+3), idx2);
2128 break;
2129 }
2130 }
2131 bytes += ent_size;
2132 size += ent_size;
2133 }
2134 assert(size == cpool_size, "Size mismatch");
2135
2136 return (int)(bytes - start_bytes);
2137 } /* end copy_cpool_bytes */
2138
2139 bool ConstantPool::is_maybe_on_stack() const {
2140 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2141 if (!Continuations::enabled()) {
2142 return false;
2143 }
2144
2145 // If the condition below is true, it means that the nmethod was found to
2146 // be alive the previous completed marking cycle.
2147 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2148 }
2149
2150 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2151 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2152 // memory for the method is reclaimed.
2153 bool ConstantPool::on_stack() const {
2154 if ((_flags &_on_stack) != 0) {
2155 return true;
2156 }
2157
2158 if (_cache == nullptr) {
2159 return false;
2160 }
2161
2162 return is_maybe_on_stack();
2163 }
2164
2165 void ConstantPool::set_on_stack(const bool value) {
2166 if (value) {
2167 // Only record if it's not already set.
2168 if (!on_stack()) {
2169 assert(!in_aot_cache(), "should always be set for constant pools in AOT cache");
2170 _flags |= _on_stack;
2171 MetadataOnStackMark::record(this);
2172 }
2173 } else {
2174 // Clearing is done single-threadedly.
2175 if (!in_aot_cache()) {
2176 _flags &= (u2)(~_on_stack);
2177 }
2178 }
2179 }
2180
2181 // Printing
2182
2183 void ConstantPool::print_on(outputStream* st) const {
2184 assert(is_constantPool(), "must be constantPool");
2185 st->print_cr("%s", internal_name());
2186 if (flags() != 0) {
2187 st->print(" - flags: 0x%x", flags());
2188 if (has_preresolution()) st->print(" has_preresolution");
2189 if (on_stack()) st->print(" on_stack");
2190 st->cr();
2191 }
2192 if (pool_holder() != nullptr) {
2193 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2194 }
2195 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2196 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2197 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2198 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2199 st->print_cr(" - cp length: %d", length());
2200
2201 for (int index = 1; index < length(); index++) { // Index 0 is unused
2202 ((ConstantPool*)this)->print_entry_on(index, st);
2203 switch (tag_at(index).value()) {
2204 case JVM_CONSTANT_Long :
2205 case JVM_CONSTANT_Double :
2206 index++; // Skip entry following eigth-byte constant
2207 }
2208
2209 }
2210 st->cr();
2211 }
2212
2213 // Print one constant pool entry
2214 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2215 EXCEPTION_MARK;
2216 st->print(" - %3d : ", cp_index);
2217 tag_at(cp_index).print_on(st);
2218 st->print(" : ");
2219 switch (tag_at(cp_index).value()) {
2220 case JVM_CONSTANT_Class :
2221 { Klass* k = klass_at(cp_index, CATCH);
2222 guarantee(k != nullptr, "need klass");
2223 k->print_value_on(st);
2224 st->print(" {" PTR_FORMAT "}", p2i(k));
2225 }
2226 break;
2227 case JVM_CONSTANT_Fieldref :
2228 case JVM_CONSTANT_Methodref :
2229 case JVM_CONSTANT_InterfaceMethodref :
2230 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2231 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2232 break;
2233 case JVM_CONSTANT_String :
2234 unresolved_string_at(cp_index)->print_value_on(st);
2235 break;
2236 case JVM_CONSTANT_Integer :
2237 st->print("%d", int_at(cp_index));
2238 break;
2239 case JVM_CONSTANT_Float :
2240 st->print("%f", float_at(cp_index));
2241 break;
2242 case JVM_CONSTANT_Long :
2243 st->print_jlong(long_at(cp_index));
2244 break;
2245 case JVM_CONSTANT_Double :
2246 st->print("%lf", double_at(cp_index));
2247 break;
2248 case JVM_CONSTANT_NameAndType :
2249 st->print("name_index=%d", name_ref_index_at(cp_index));
2250 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2251 break;
2252 case JVM_CONSTANT_Utf8 :
2253 symbol_at(cp_index)->print_value_on(st);
2254 break;
2255 case JVM_CONSTANT_ClassIndex: {
2256 int name_index = *int_at_addr(cp_index);
2257 st->print("klass_index=%d ", name_index);
2258 symbol_at(name_index)->print_value_on(st);
2259 }
2260 break;
2261 case JVM_CONSTANT_UnresolvedClass : // fall-through
2262 case JVM_CONSTANT_UnresolvedClassInError: {
2263 CPKlassSlot kslot = klass_slot_at(cp_index);
2264 int resolved_klass_index = kslot.resolved_klass_index();
2265 int name_index = kslot.name_index();
2266 assert(tag_at(name_index).is_symbol(), "sanity");
2267 symbol_at(name_index)->print_value_on(st);
2268 }
2269 break;
2270 case JVM_CONSTANT_MethodHandle :
2271 case JVM_CONSTANT_MethodHandleInError :
2272 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2273 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2274 break;
2275 case JVM_CONSTANT_MethodType :
2276 case JVM_CONSTANT_MethodTypeInError :
2277 st->print("signature_index=%d", method_type_index_at(cp_index));
2278 break;
2279 case JVM_CONSTANT_Dynamic :
2280 case JVM_CONSTANT_DynamicInError :
2281 {
2282 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2283 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2284 int argc = bootstrap_argument_count_at(cp_index);
2285 if (argc > 0) {
2286 for (int arg_i = 0; arg_i < argc; arg_i++) {
2287 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2288 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2289 }
2290 st->print("}");
2291 }
2292 }
2293 break;
2294 case JVM_CONSTANT_InvokeDynamic :
2295 {
2296 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2297 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2298 int argc = bootstrap_argument_count_at(cp_index);
2299 if (argc > 0) {
2300 for (int arg_i = 0; arg_i < argc; arg_i++) {
2301 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2302 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2303 }
2304 st->print("}");
2305 }
2306 }
2307 break;
2308 default:
2309 ShouldNotReachHere();
2310 break;
2311 }
2312 st->cr();
2313 }
2314
2315 void ConstantPool::print_value_on(outputStream* st) const {
2316 assert(is_constantPool(), "must be constantPool");
2317 st->print("constant pool [%d]", length());
2318 if (has_preresolution()) st->print("/preresolution");
2319 if (!bsm_entries().is_empty()) st->print("/BSMs[%d]", bsm_entries().bootstrap_methods()->length());
2320 print_address_on(st);
2321 if (pool_holder() != nullptr) {
2322 st->print(" for ");
2323 pool_holder()->print_value_on(st);
2324 bool extra = (pool_holder()->constants() != this);
2325 if (extra) st->print(" (extra)");
2326 }
2327 if (cache() != nullptr) {
2328 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2329 }
2330 }
2331
2332 // Verification
2333
2334 void ConstantPool::verify_on(outputStream* st) {
2335 guarantee(is_constantPool(), "object must be constant pool");
2336 for (int i = 0; i< length(); i++) {
2337 constantTag tag = tag_at(i);
2338 if (tag.is_klass() || tag.is_unresolved_klass()) {
2339 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2340 } else if (tag.is_symbol()) {
2341 Symbol* entry = symbol_at(i);
2342 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2343 } else if (tag.is_string()) {
2344 Symbol* entry = unresolved_string_at(i);
2345 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2346 }
2347 }
2348 if (pool_holder() != nullptr) {
2349 // Note: pool_holder() can be null in temporary constant pools
2350 // used during constant pool merging
2351 guarantee(pool_holder()->is_klass(), "should be klass");
2352 }
2353 }
2354
2355 void BSMAttributeEntries::deallocate_contents(ClassLoaderData* loader_data) {
2356 MetadataFactory::free_array<u4>(loader_data, this->_offsets);
2357 MetadataFactory::free_array<u2>(loader_data, this->_bootstrap_methods);
2358 this->_offsets = nullptr;
2359 this->_bootstrap_methods = nullptr;
2360 }
2361
2362 void BSMAttributeEntries::copy_into(InsertionIterator& iter, int num_entries) const {
2363 assert(num_entries + iter._cur_offset <= iter._insert_into->_offsets->length(), "must");
2364 for (int i = 0; i < num_entries; i++) {
2365 const BSMAttributeEntry* e = entry(i);
2366 BSMAttributeEntry* e_new = iter.reserve_new_entry(e->bootstrap_method_index(), e->argument_count());
2367 assert(e_new != nullptr, "must be");
2368 e->copy_args_into(e_new);
2369 }
2370 }
2371
2372 BSMAttributeEntries::InsertionIterator
2373 BSMAttributeEntries::start_extension(const BSMAttributeEntries& other, ClassLoaderData* loader_data, TRAPS) {
2374 InsertionIterator iter = start_extension(other.number_of_entries(), other.array_length(),
2375 loader_data, CHECK_(BSMAttributeEntries::InsertionIterator()));
2376 return iter;
2377 }
2378
2379 BSMAttributeEntries::InsertionIterator
2380 BSMAttributeEntries::start_extension(int number_of_entries, int array_length,
2381 ClassLoaderData* loader_data, TRAPS) {
2382 InsertionIterator extension_iterator(this, this->number_of_entries(), this->array_length());
2383 int new_number_of_entries = this->number_of_entries() + number_of_entries;
2384 int new_array_length = this->array_length() + array_length;
2385 int invalid_index = new_array_length;
2386
2387 Array<u4>* new_offsets =
2388 MetadataFactory::new_array<u4>(loader_data, new_number_of_entries, invalid_index, CHECK_(InsertionIterator()));
2389 Array<u2>* new_array = MetadataFactory::new_array<u2>(loader_data, new_array_length, CHECK_(InsertionIterator()));
2390 { // Copy over all the old BSMAEntry's and their respective offsets
2391 BSMAttributeEntries carrier(new_offsets, new_array);
2392 InsertionIterator copy_iter(&carrier, 0, 0);
2393 copy_into(copy_iter, this->number_of_entries());
2394 }
2395 // Replace content
2396 deallocate_contents(loader_data);
2397 _offsets = new_offsets;
2398 _bootstrap_methods = new_array;
2399 return extension_iterator;
2400 }
2401
2402
2403 void BSMAttributeEntries::append(const BSMAttributeEntries& other, ClassLoaderData* loader_data, TRAPS) {
2404 if (other.number_of_entries() == 0) {
2405 return; // Done!
2406 }
2407 InsertionIterator iter = start_extension(other, loader_data, CHECK);
2408 other.copy_into(iter, other.number_of_entries());
2409 end_extension(iter, loader_data, THREAD);
2410 }
2411
2412 void BSMAttributeEntries::end_extension(InsertionIterator& iter, ClassLoaderData* loader_data, TRAPS) {
2413 assert(iter._insert_into == this, "must be");
2414 assert(iter._cur_offset <= this->_offsets->length(), "must be");
2415 assert(iter._cur_array <= this->_bootstrap_methods->length(), "must be");
2416
2417 // Did we fill up all of the available space? If so, do nothing.
2418 if (iter._cur_offset == this->_offsets->length() &&
2419 iter._cur_array == this->_bootstrap_methods->length()) {
2420 return;
2421 }
2422
2423 // We used less, truncate by allocating new arrays
2424 Array<u4>* new_offsets =
2425 MetadataFactory::new_array<u4>(loader_data, iter._cur_offset, 0, CHECK);
2426 Array<u2>* new_array =
2427 MetadataFactory::new_array<u2>(loader_data, iter._cur_array, CHECK);
2428 { // Copy over the constructed BSMAEntry's
2429 BSMAttributeEntries carrier(new_offsets, new_array);
2430 InsertionIterator copy_iter(&carrier, 0, 0);
2431 copy_into(copy_iter, iter._cur_offset);
2432 }
2433
2434 deallocate_contents(loader_data);
2435 _offsets = new_offsets;
2436 _bootstrap_methods = new_array;
2437 }