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/archiveHeapLoader.hpp"
28 #include "cds/archiveHeapWriter.hpp"
29 #include "cds/cdsConfig.hpp"
30 #include "cds/heapShared.hpp"
31 #include "classfile/classLoader.hpp"
32 #include "classfile/classLoaderData.hpp"
33 #include "classfile/javaClasses.inline.hpp"
34 #include "classfile/metadataOnStackMark.hpp"
35 #include "classfile/stringTable.hpp"
36 #include "classfile/systemDictionary.hpp"
37 #include "classfile/systemDictionaryShared.hpp"
38 #include "classfile/vmClasses.hpp"
39 #include "classfile/vmSymbols.hpp"
40 #include "code/codeCache.hpp"
41 #include "interpreter/bootstrapInfo.hpp"
42 #include "interpreter/linkResolver.hpp"
43 #include "jvm.h"
44 #include "logging/log.hpp"
45 #include "logging/logStream.hpp"
46 #include "memory/allocation.inline.hpp"
47 #include "memory/metadataFactory.hpp"
48 #include "memory/metaspaceClosure.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/array.hpp"
53 #include "oops/constantPool.inline.hpp"
54 #include "oops/cpCache.inline.hpp"
55 #include "oops/fieldStreams.inline.hpp"
56 #include "oops/instanceKlass.hpp"
57 #include "oops/klass.inline.hpp"
58 #include "oops/objArrayKlass.hpp"
59 #include "oops/objArrayOop.inline.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/typeArrayOop.inline.hpp"
62 #include "prims/jvmtiExport.hpp"
63 #include "runtime/atomic.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 MetadataFactory::free_array<jushort>(loader_data, operands());
137 set_operands(nullptr);
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(cds)("Iter(ConstantPool): %p", this);
153
154 it->push(&_tags, MetaspaceClosure::_writable);
155 it->push(&_cache);
156 it->push(&_pool_holder);
157 it->push(&_operands);
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 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 ClassIndex 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 Atomic::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 (!ArchiveHeapWriter::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
378 void ConstantPool::add_dumped_interned_strings() {
379 InstanceKlass* ik = pool_holder();
380 if (!ik->is_linked()) {
381 // resolved_references() doesn't exist yet, so we have no resolved CONSTANT_String entries. However,
382 // some static final fields may have default values that were initialized when the class was parsed.
383 // We need to enter those into the CDS archive strings table.
384 for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
385 if (fs.access_flags().is_static()) {
386 fieldDescriptor& fd = fs.field_descriptor();
387 if (fd.field_type() == T_OBJECT) {
388 int offset = fd.offset();
389 check_and_add_dumped_interned_string(ik->java_mirror()->obj_field(offset));
390 }
391 }
392 }
393 } else {
394 objArrayOop rr = resolved_references();
395 if (rr != nullptr) {
396 int rr_len = rr->length();
397 for (int i = 0; i < rr_len; i++) {
398 check_and_add_dumped_interned_string(rr->obj_at(i));
399 }
400 }
401 }
402 }
403
404 void ConstantPool::check_and_add_dumped_interned_string(oop obj) {
405 if (obj != nullptr && java_lang_String::is_instance(obj) &&
406 !ArchiveHeapWriter::is_string_too_large_to_archive(obj)) {
407 HeapShared::add_to_dumped_interned_strings(obj);
408 }
409 }
410
411 #endif
412
413 #if INCLUDE_CDS
414 // CDS support. Create a new resolved_references array.
415 void ConstantPool::restore_unshareable_info(TRAPS) {
416 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
417 return;
418 }
419 assert(is_constantPool(), "ensure C++ vtable is restored");
420 assert(on_stack(), "should always be set for shared constant pools");
421 assert(is_shared(), "should always be set for shared constant pools");
422 if (is_for_method_handle_intrinsic()) {
423 // See the same check in remove_unshareable_info() below.
424 assert(cache() == nullptr, "must not have cpCache");
425 return;
426 }
427 assert(_cache != nullptr, "constant pool _cache should not be null");
428
429 // Only create the new resolved references array if it hasn't been attempted before
430 if (resolved_references() != nullptr) return;
431
432 if (vmClasses::Object_klass_loaded()) {
433 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
434 #if INCLUDE_CDS_JAVA_HEAP
435 if (ArchiveHeapLoader::is_in_use() &&
436 _cache->archived_references() != nullptr) {
437 oop archived = _cache->archived_references();
438 // Create handle for the archived resolved reference array object
439 HandleMark hm(THREAD);
440 Handle refs_handle(THREAD, archived);
441 set_resolved_references(loader_data->add_handle(refs_handle));
442 _cache->clear_archived_references();
443 } else
444 #endif
445 {
446 // No mapped archived resolved reference array
447 // Recreate the object array and add to ClassLoaderData.
448 int map_length = resolved_reference_length();
449 if (map_length > 0) {
450 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
451 HandleMark hm(THREAD);
452 Handle refs_handle(THREAD, stom); // must handleize.
453 set_resolved_references(loader_data->add_handle(refs_handle));
454 }
455 }
456 }
457
458 if (CDSConfig::is_dumping_final_static_archive() && CDSConfig::is_dumping_heap() && resolved_references() != nullptr) {
459 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), resolved_references()->length(), CHECK);
460 HeapShared::add_scratch_resolved_references(this, scratch_references);
461 }
462 }
463
464 void ConstantPool::remove_unshareable_info() {
465 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
466 // The _on_stack flag is used to prevent ConstantPools from deallocation during
467 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
468 // we always set _on_stack to true to avoid having to change _flags during runtime.
469 _flags |= (_on_stack | _is_shared);
470
471 if (is_for_method_handle_intrinsic()) {
472 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
473 // that need to be removed/restored. It has no cpCache since the intrinsic methods
474 // don't have any bytecodes.
475 assert(cache() == nullptr, "must not have cpCache");
476 return;
477 }
478
479 bool update_resolved_reference = true;
480 if (CDSConfig::is_dumping_final_static_archive()) {
481 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
482 InstanceKlass* src_holder = src_cp->pool_holder();
483 if (src_holder->is_shared_unregistered_class()) {
484 // Unregistered classes are not loaded in the AOT assembly phase. The resolved reference length
485 // is already saved during the training run.
486 precond(!src_holder->is_loaded());
487 precond(resolved_reference_length() >= 0);
488 precond(resolved_references() == nullptr);
489 update_resolved_reference = false;
490 }
491 }
492
493 // resolved_references(): remember its length. If it cannot be restored
494 // from the archived heap objects at run time, we need to dynamically allocate it.
495 if (update_resolved_reference && cache() != nullptr) {
496 set_resolved_reference_length(
497 resolved_references() != nullptr ? resolved_references()->length() : 0);
498 set_resolved_references(OopHandle());
499 }
500 remove_unshareable_entries();
501 }
502
503 static const char* get_type(Klass* k) {
504 const char* type;
505 Klass* src_k;
506 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
507 src_k = ArchiveBuilder::current()->get_source_addr(k);
508 } else {
509 src_k = k;
510 }
511
512 if (src_k->is_objArray_klass()) {
513 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
514 assert(!src_k->is_objArray_klass(), "sanity");
515 }
516
517 if (src_k->is_typeArray_klass()) {
518 type = "prim";
519 } else {
520 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
521 oop loader = src_ik->class_loader();
522 if (loader == nullptr) {
523 type = "boot";
524 } else if (loader == SystemDictionary::java_platform_loader()) {
525 type = "plat";
526 } else if (loader == SystemDictionary::java_system_loader()) {
527 type = "app";
528 } else {
529 type = "unreg";
530 }
531 }
532
533 return type;
534 }
535
536 void ConstantPool::remove_unshareable_entries() {
537 ResourceMark rm;
538 log_info(cds, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
539 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
540 int cp_tag = tag_at(cp_index).value();
541 switch (cp_tag) {
542 case JVM_CONSTANT_UnresolvedClass:
543 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, false);
544 break;
545 case JVM_CONSTANT_UnresolvedClassInError:
546 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
547 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, true);
548 break;
549 case JVM_CONSTANT_MethodHandleInError:
550 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
551 break;
552 case JVM_CONSTANT_MethodTypeInError:
553 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
554 break;
555 case JVM_CONSTANT_DynamicInError:
556 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
557 break;
558 case JVM_CONSTANT_Class:
559 remove_resolved_klass_if_non_deterministic(cp_index);
560 break;
561 default:
562 break;
563 }
564 }
565
566 if (cache() != nullptr) {
567 // cache() is null if this class is not yet linked.
568 cache()->remove_unshareable_info();
569 }
570 }
571
572 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
573 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
574 assert(tag_at(cp_index).is_klass(), "must be resolved");
575
576 Klass* k = resolved_klass_at(cp_index);
577 bool can_archive;
578
579 if (k == nullptr) {
580 // We'd come here if the referenced class has been excluded via
581 // SystemDictionaryShared::is_excluded_class(). As a result, ArchiveBuilder
582 // has cleared the resolved_klasses()->at(...) pointer to null. Thus, we
583 // need to revert the tag to JVM_CONSTANT_UnresolvedClass.
584 can_archive = false;
585 } else {
586 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
587 can_archive = AOTConstantPoolResolver::is_resolution_deterministic(src_cp, cp_index);
588 }
589
590 if (!can_archive) {
591 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
592 // This might be at a safepoint but do this in the right order.
593 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
594 resolved_klasses()->at_put(resolved_klass_index, nullptr);
595 }
596
597 LogStreamHandle(Trace, cds, resolve) log;
598 if (log.is_enabled()) {
599 ResourceMark rm;
600 log.print("%s klass CP entry [%3d]: %s %s",
601 (can_archive ? "archived" : "reverted"),
602 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
603 if (can_archive) {
604 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
605 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
606 } else {
607 Symbol* name = klass_name_at(cp_index);
608 log.print(" => %s", name->as_C_string());
609 }
610 }
611
612 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(can_archive, /*reverted=*/!can_archive);
613 }
614 #endif // INCLUDE_CDS
615
616 int ConstantPool::cp_to_object_index(int cp_index) {
617 // this is harder don't do this so much.
618 int i = reference_map()->find(checked_cast<u2>(cp_index));
619 // We might not find the index for jsr292 call.
620 return (i < 0) ? _no_index_sentinel : i;
621 }
622
623 void ConstantPool::string_at_put(int obj_index, oop str) {
624 oop result = set_resolved_reference_at(obj_index, str);
625 assert(result == nullptr || result == str, "Only set once or to the same string.");
626 }
627
628 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
629 ResourceMark rm;
630 int line_number = -1;
631 const char * source_file = nullptr;
632 if (JavaThread::current()->has_last_Java_frame()) {
633 // try to identify the method which called this function.
634 vframeStream vfst(JavaThread::current());
635 if (!vfst.at_end()) {
636 line_number = vfst.method()->line_number_from_bci(vfst.bci());
637 Symbol* s = vfst.method()->method_holder()->source_file_name();
638 if (s != nullptr) {
639 source_file = s->as_C_string();
640 }
641 }
642 }
643 if (k != this_cp->pool_holder()) {
644 // only print something if the classes are different
645 if (source_file != nullptr) {
646 log_debug(class, resolve)("%s %s %s:%d",
647 this_cp->pool_holder()->external_name(),
648 k->external_name(), source_file, line_number);
649 } else {
650 log_debug(class, resolve)("%s %s",
651 this_cp->pool_holder()->external_name(),
652 k->external_name());
653 }
654 }
655 }
656
657 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
658 TRAPS) {
659 JavaThread* javaThread = THREAD;
660
661 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
662 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
663 // the entry and tag is not updated atomically.
664 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
665 int resolved_klass_index = kslot.resolved_klass_index();
666 int name_index = kslot.name_index();
667 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
668
669 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
670 // the unresolved_klasses() array.
671 if (this_cp->tag_at(cp_index).is_klass()) {
672 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
673 assert(klass != nullptr, "must be resolved");
674 return klass;
675 }
676
677 // This tag doesn't change back to unresolved class unless at a safepoint.
678 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
679 // The original attempt to resolve this constant pool entry failed so find the
680 // class of the original error and throw another error of the same class
681 // (JVMS 5.4.3).
682 // If there is a detail message, pass that detail message to the error.
683 // The JVMS does not strictly require us to duplicate the same detail message,
684 // or any internal exception fields such as cause or stacktrace. But since the
685 // detail message is often a class name or other literal string, we will repeat it
686 // if we can find it in the symbol table.
687 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
688 ShouldNotReachHere();
689 }
690
691 HandleMark hm(THREAD);
692 Handle mirror_handle;
693 Symbol* name = this_cp->symbol_at(name_index);
694 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
695
696 Klass* k;
697 {
698 // Turn off the single stepping while doing class resolution
699 JvmtiHideSingleStepping jhss(javaThread);
700 k = SystemDictionary::resolve_or_fail(name, loader, true, THREAD);
701 } // JvmtiHideSingleStepping jhss(javaThread);
702
703 if (!HAS_PENDING_EXCEPTION) {
704 // preserve the resolved klass from unloading
705 mirror_handle = Handle(THREAD, k->java_mirror());
706 // Do access check for klasses
707 verify_constant_pool_resolve(this_cp, k, THREAD);
708 }
709
710 // Failed to resolve class. We must record the errors so that subsequent attempts
711 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
712 if (HAS_PENDING_EXCEPTION) {
713 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
714 // If CHECK_NULL above doesn't return the exception, that means that
715 // some other thread has beaten us and has resolved the class.
716 // To preserve old behavior, we return the resolved class.
717 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
718 assert(klass != nullptr, "must be resolved if exception was cleared");
719 return klass;
720 }
721
722 // logging for class+resolve.
723 if (log_is_enabled(Debug, class, resolve)){
724 trace_class_resolution(this_cp, k);
725 }
726
727 // The interpreter assumes when the tag is stored, the klass is resolved
728 // and the Klass* stored in _resolved_klasses is non-null, so we need
729 // hardware store ordering here.
730 // We also need to CAS to not overwrite an error from a racing thread.
731 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
732 Atomic::release_store(adr, k);
733
734 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
735 (jbyte)JVM_CONSTANT_UnresolvedClass,
736 (jbyte)JVM_CONSTANT_Class);
737
738 // We need to recheck exceptions from racing thread and return the same.
739 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
740 // Remove klass.
741 Atomic::store(adr, (Klass*)nullptr);
742 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
743 }
744
745 return k;
746 }
747
748
749 // Does not update ConstantPool* - to avoid any exception throwing. Used
750 // by compiler and exception handling. Also used to avoid classloads for
751 // instanceof operations. Returns null if the class has not been loaded or
752 // if the verification of constant pool failed
753 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
754 CPKlassSlot kslot = this_cp->klass_slot_at(which);
755 int resolved_klass_index = kslot.resolved_klass_index();
756 int name_index = kslot.name_index();
757 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
758
759 if (this_cp->tag_at(which).is_klass()) {
760 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
761 assert(k != nullptr, "must be resolved");
762 return k;
763 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
764 return nullptr;
765 } else {
766 Thread* current = Thread::current();
767 HandleMark hm(current);
768 Symbol* name = this_cp->symbol_at(name_index);
769 oop loader = this_cp->pool_holder()->class_loader();
770 Handle h_loader (current, loader);
771 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader);
772
773 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
774 if (k != nullptr && current->is_Java_thread()) {
775 // Make sure that resolving is legal
776 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
777 ExceptionMark em(THREAD);
778 // return null if verification fails
779 verify_constant_pool_resolve(this_cp, k, THREAD);
780 if (HAS_PENDING_EXCEPTION) {
781 CLEAR_PENDING_EXCEPTION;
782 return nullptr;
783 }
784 return k;
785 } else {
786 return k;
787 }
788 }
789 }
790
791 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
792 int which) {
793 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
794 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
795 // FIXME: should be an assert
796 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
797 return nullptr;
798 }
799 return cpool->cache()->method_if_resolved(which);
800 }
801
802
803 bool ConstantPool::has_appendix_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_appendix();
807 } else {
808 return cpool->resolved_method_entry_at(which)->has_appendix();
809 }
810 }
811
812 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
813 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
814 if (code == Bytecodes::_invokedynamic) {
815 return cpool->resolved_reference_from_indy(which);
816 } else {
817 return cpool->cache()->appendix_if_resolved(which);
818 }
819 }
820
821
822 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
823 if (cpool->cache() == nullptr) return false; // nothing to load yet
824 if (code == Bytecodes::_invokedynamic) {
825 return cpool->resolved_indy_entry_at(which)->has_local_signature();
826 } else {
827 return cpool->resolved_method_entry_at(which)->has_local_signature();
828 }
829 }
830
831 // Translate index, which could be CPCache index or Indy index, to a constant pool index
832 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
833 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
834 switch(code) {
835 case Bytecodes::_invokedynamic:
836 return invokedynamic_bootstrap_ref_index_at(index);
837 case Bytecodes::_getfield:
838 case Bytecodes::_getstatic:
839 case Bytecodes::_putfield:
840 case Bytecodes::_putstatic:
841 return resolved_field_entry_at(index)->constant_pool_index();
842 case Bytecodes::_invokeinterface:
843 case Bytecodes::_invokehandle:
844 case Bytecodes::_invokespecial:
845 case Bytecodes::_invokestatic:
846 case Bytecodes::_invokevirtual:
847 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
848 return resolved_method_entry_at(index)->constant_pool_index();
849 default:
850 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
851 }
852 }
853
854 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
855 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
856 switch(code) {
857 case Bytecodes::_invokedynamic:
858 return resolved_indy_entry_at(index)->is_resolved();
859
860 case Bytecodes::_getfield:
861 case Bytecodes::_getstatic:
862 case Bytecodes::_putfield:
863 case Bytecodes::_putstatic:
864 return resolved_field_entry_at(index)->is_resolved(code);
865
866 case Bytecodes::_invokeinterface:
867 case Bytecodes::_invokehandle:
868 case Bytecodes::_invokespecial:
869 case Bytecodes::_invokestatic:
870 case Bytecodes::_invokevirtual:
871 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
872 return resolved_method_entry_at(index)->is_resolved(code);
873
874 default:
875 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
876 }
877 }
878
879 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
880 if (tag_at(cp_index).has_bootstrap()) {
881 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
882 assert(tag_at(pool_index).is_name_and_type(), "");
883 return pool_index;
884 }
885 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
886 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
887 jint ref_index = *int_at_addr(cp_index);
888 return extract_high_short_from_int(ref_index);
889 }
890
891 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
892 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
893 }
894
895 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
896 // which may be either a Constant Pool index or a rewritten index
897 int pool_index = which;
898 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
899 pool_index = to_cp_index(which, code);
900 return tag_at(pool_index);
901 }
902
903 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
904 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
905 jint ref_index = *int_at_addr(cp_index);
906 return extract_low_short_from_int(ref_index);
907 }
908
909 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
910 assert(code != Bytecodes::_invokedynamic,
911 "an invokedynamic instruction does not have a klass");
912 return uncached_klass_ref_index_at(to_cp_index(index, code));
913 }
914
915 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
916 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
917 return; // short cut, typeArray klass is always accessible
918 }
919 Klass* holder = this_cp->pool_holder();
920 LinkResolver::check_klass_accessibility(holder, k, CHECK);
921 }
922
923
924 u2 ConstantPool::name_ref_index_at(int cp_index) {
925 jint ref_index = name_and_type_at(cp_index);
926 return extract_low_short_from_int(ref_index);
927 }
928
929
930 u2 ConstantPool::signature_ref_index_at(int cp_index) {
931 jint ref_index = name_and_type_at(cp_index);
932 return extract_high_short_from_int(ref_index);
933 }
934
935
936 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
937 return klass_at(klass_ref_index_at(which, code), THREAD);
938 }
939
940 Symbol* ConstantPool::klass_name_at(int cp_index) const {
941 return symbol_at(klass_slot_at(cp_index).name_index());
942 }
943
944 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
945 jint ref_index = klass_ref_index_at(which, code);
946 return klass_at_noresolve(ref_index);
947 }
948
949 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
950 jint ref_index = uncached_klass_ref_index_at(cp_index);
951 return klass_at_noresolve(ref_index);
952 }
953
954 char* ConstantPool::string_at_noresolve(int cp_index) {
955 return unresolved_string_at(cp_index)->as_C_string();
956 }
957
958 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
959 return Signature::basic_type(symbol_at(cp_index));
960 }
961
962
963 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
964 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
965 if (this_cp->tag_at(index).is_string()) {
966 this_cp->string_at(index, CHECK);
967 }
968 }
969 }
970
971 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
972 // Note: caller needs ResourceMark
973
974 // Dig out the detailed message to reuse if possible
975 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
976 if (msg != nullptr) {
977 return msg;
978 }
979
980 Symbol* message = nullptr;
981 // Return specific message for the tag
982 switch (tag.value()) {
983 case JVM_CONSTANT_UnresolvedClass:
984 // return the class name in the error message
985 message = this_cp->klass_name_at(which);
986 break;
987 case JVM_CONSTANT_MethodHandle:
988 // return the method handle name in the error message
989 message = this_cp->method_handle_name_ref_at(which);
990 break;
991 case JVM_CONSTANT_MethodType:
992 // return the method type signature in the error message
993 message = this_cp->method_type_signature_at(which);
994 break;
995 case JVM_CONSTANT_Dynamic:
996 // return the name of the condy in the error message
997 message = this_cp->uncached_name_ref_at(which);
998 break;
999 default:
1000 ShouldNotReachHere();
1001 }
1002
1003 return message != nullptr ? message->as_C_string() : nullptr;
1004 }
1005
1006 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
1007 constantTag tag, oop pending_exception) {
1008
1009 ResourceMark rm(current);
1010 Symbol* error = pending_exception->klass()->name();
1011 oop cause = java_lang_Throwable::cause(pending_exception);
1012
1013 // Also dig out the exception cause, if present.
1014 Symbol* cause_sym = nullptr;
1015 const char* cause_msg = nullptr;
1016 if (cause != nullptr && cause != pending_exception) {
1017 cause_sym = cause->klass()->name();
1018 cause_msg = java_lang_Throwable::message_as_utf8(cause);
1019 }
1020
1021 const char* message = exception_message(this_cp, which, tag, pending_exception);
1022 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1023 }
1024
1025
1026 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1027 ResourceMark rm(THREAD);
1028 const char* message = nullptr;
1029 Symbol* cause = nullptr;
1030 const char* cause_msg = nullptr;
1031 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1032 assert(error != nullptr, "checking");
1033
1034 CLEAR_PENDING_EXCEPTION;
1035 if (message != nullptr) {
1036 if (cause != nullptr) {
1037 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1038 THROW_MSG_CAUSE(error, message, h_cause);
1039 } else {
1040 THROW_MSG(error, message);
1041 }
1042 } else {
1043 if (cause != nullptr) {
1044 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1045 THROW_CAUSE(error, h_cause);
1046 } else {
1047 THROW(error);
1048 }
1049 }
1050 }
1051
1052 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1053 // exception in the resolution error table, so that the same exception is thrown again.
1054 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1055 constantTag tag, TRAPS) {
1056
1057 int error_tag = tag.error_value();
1058
1059 if (!PENDING_EXCEPTION->
1060 is_a(vmClasses::LinkageError_klass())) {
1061 // Just throw the exception and don't prevent these classes from
1062 // being loaded due to virtual machine errors like StackOverflow
1063 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1064 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1065 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1066 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1067 // CAS in the tag. If a thread beat us to registering this error that's fine.
1068 // If another thread resolved the reference, this is a race condition. This
1069 // thread may have had a security manager or something temporary.
1070 // This doesn't deterministically get an error. So why do we save this?
1071 // We save this because jvmti can add classes to the bootclass path after
1072 // this error, so it needs to get the same error if the error is first.
1073 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1074 (jbyte)tag.value(),
1075 (jbyte)error_tag);
1076 if (old_tag != error_tag && old_tag != tag.value()) {
1077 // MethodHandles and MethodType doesn't change to resolved version.
1078 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1079 // Forget the exception and use the resolved class.
1080 CLEAR_PENDING_EXCEPTION;
1081 }
1082 } else {
1083 // some other thread put this in error state
1084 throw_resolution_error(this_cp, cp_index, CHECK);
1085 }
1086 }
1087
1088 constantTag ConstantPool::constant_tag_at(int cp_index) {
1089 constantTag tag = tag_at(cp_index);
1090 if (tag.is_dynamic_constant()) {
1091 BasicType bt = basic_type_for_constant_at(cp_index);
1092 return constantTag(constantTag::type2tag(bt));
1093 }
1094 return tag;
1095 }
1096
1097 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1098 constantTag tag = tag_at(cp_index);
1099 if (tag.is_dynamic_constant() ||
1100 tag.is_dynamic_constant_in_error()) {
1101 // have to look at the signature for this one
1102 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1103 return Signature::basic_type(constant_type);
1104 }
1105 return tag.basic_type();
1106 }
1107
1108 // Called to resolve constants in the constant pool and return an oop.
1109 // Some constant pool entries cache their resolved oop. This is also
1110 // called to create oops from constants to use in arguments for invokedynamic
1111 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1112 int cp_index, int cache_index,
1113 bool* status_return, TRAPS) {
1114 oop result_oop = nullptr;
1115
1116 if (cache_index == _possible_index_sentinel) {
1117 // It is possible that this constant is one which is cached in the objects.
1118 // We'll do a linear search. This should be OK because this usage is rare.
1119 // FIXME: If bootstrap specifiers stress this code, consider putting in
1120 // a reverse index. Binary search over a short array should do it.
1121 assert(cp_index > 0, "valid constant pool index");
1122 cache_index = this_cp->cp_to_object_index(cp_index);
1123 }
1124 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1125 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1126
1127 if (cache_index >= 0) {
1128 result_oop = this_cp->resolved_reference_at(cache_index);
1129 if (result_oop != nullptr) {
1130 if (result_oop == Universe::the_null_sentinel()) {
1131 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1132 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1133 result_oop = nullptr;
1134 }
1135 if (status_return != nullptr) (*status_return) = true;
1136 return result_oop;
1137 // That was easy...
1138 }
1139 cp_index = this_cp->object_to_cp_index(cache_index);
1140 }
1141
1142 jvalue prim_value; // temp used only in a few cases below
1143
1144 constantTag tag = this_cp->tag_at(cp_index);
1145
1146 if (status_return != nullptr) {
1147 // don't trigger resolution if the constant might need it
1148 switch (tag.value()) {
1149 case JVM_CONSTANT_Class:
1150 assert(this_cp->resolved_klass_at(cp_index) != nullptr, "must be resolved");
1151 break;
1152 case JVM_CONSTANT_String:
1153 case JVM_CONSTANT_Integer:
1154 case JVM_CONSTANT_Float:
1155 case JVM_CONSTANT_Long:
1156 case JVM_CONSTANT_Double:
1157 // these guys trigger OOM at worst
1158 break;
1159 default:
1160 (*status_return) = false;
1161 return nullptr;
1162 }
1163 // from now on there is either success or an OOME
1164 (*status_return) = true;
1165 }
1166
1167 switch (tag.value()) {
1168
1169 case JVM_CONSTANT_UnresolvedClass:
1170 case JVM_CONSTANT_Class:
1171 {
1172 assert(cache_index == _no_index_sentinel, "should not have been set");
1173 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1174 // ldc wants the java mirror.
1175 result_oop = resolved->java_mirror();
1176 break;
1177 }
1178
1179 case JVM_CONSTANT_Dynamic:
1180 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1181 ClassLoader::perf_resolve_invokedynamic_count());
1182
1183 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1184 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1185
1186 // The initial step in resolving an unresolved symbolic reference to a
1187 // dynamically-computed constant is to resolve the symbolic reference to a
1188 // method handle which will be the bootstrap method for the dynamically-computed
1189 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1190 // method fails, then a MethodHandleInError is stored at the corresponding
1191 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1192 // set a DynamicConstantInError here since any subsequent use of this
1193 // bootstrap method will encounter the resolution of MethodHandleInError.
1194 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1195 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1196 // for the bootstrap_specifier created above.
1197 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1198 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1199 if (HAS_PENDING_EXCEPTION) {
1200 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1201 // will check for a LinkageError and store a DynamicConstantInError.
1202 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1203 }
1204 result_oop = bootstrap_specifier.resolved_value()();
1205 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1206 if (!is_reference_type(type)) {
1207 // Make sure the primitive value is properly boxed.
1208 // This is a JDK responsibility.
1209 const char* fail = nullptr;
1210 if (result_oop == nullptr) {
1211 fail = "null result instead of box";
1212 } else if (!is_java_primitive(type)) {
1213 // FIXME: support value types via unboxing
1214 fail = "can only handle references and primitives";
1215 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1216 fail = "primitive is not properly boxed";
1217 }
1218 if (fail != nullptr) {
1219 // Since this exception is not a LinkageError, throw exception
1220 // but do not save a DynamicInError resolution result.
1221 // See section 5.4.3 of the VM spec.
1222 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1223 }
1224 }
1225
1226 LogTarget(Debug, methodhandles, condy) lt_condy;
1227 if (lt_condy.is_enabled()) {
1228 LogStream ls(lt_condy);
1229 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1230 }
1231 break;
1232 }
1233
1234 case JVM_CONSTANT_String:
1235 assert(cache_index != _no_index_sentinel, "should have been set");
1236 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1237 break;
1238
1239 case JVM_CONSTANT_MethodHandle:
1240 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1241 ClassLoader::perf_resolve_method_handle_count());
1242
1243 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1244 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1245 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1246 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1247 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1248 { ResourceMark rm(THREAD);
1249 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1250 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1251 callee_index, name->as_C_string(), signature->as_C_string());
1252 }
1253
1254 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1255 if (HAS_PENDING_EXCEPTION) {
1256 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1257 }
1258
1259 // Check constant pool method consistency
1260 if ((callee->is_interface() && m_tag.is_method()) ||
1261 (!callee->is_interface() && m_tag.is_interface_method())) {
1262 ResourceMark rm(THREAD);
1263 stringStream ss;
1264 ss.print("Inconsistent constant pool data in classfile for class %s. "
1265 "Method '", callee->name()->as_C_string());
1266 signature->print_as_signature_external_return_type(&ss);
1267 ss.print(" %s(", name->as_C_string());
1268 signature->print_as_signature_external_parameters(&ss);
1269 ss.print(")' at index %d is %s and should be %s",
1270 cp_index,
1271 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1272 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1273 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1274 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1275 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1276 }
1277
1278 Klass* klass = this_cp->pool_holder();
1279 HandleMark hm(THREAD);
1280 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1281 callee, name, signature,
1282 THREAD);
1283 if (HAS_PENDING_EXCEPTION) {
1284 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1285 }
1286 result_oop = value();
1287 break;
1288 }
1289
1290 case JVM_CONSTANT_MethodType:
1291 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1292 ClassLoader::perf_resolve_method_type_count());
1293
1294 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1295 { ResourceMark rm(THREAD);
1296 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1297 cp_index, this_cp->method_type_index_at(cp_index),
1298 signature->as_C_string());
1299 }
1300 Klass* klass = this_cp->pool_holder();
1301 HandleMark hm(THREAD);
1302 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1303 result_oop = value();
1304 if (HAS_PENDING_EXCEPTION) {
1305 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1306 }
1307 break;
1308 }
1309
1310 case JVM_CONSTANT_Integer:
1311 assert(cache_index == _no_index_sentinel, "should not have been set");
1312 prim_value.i = this_cp->int_at(cp_index);
1313 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1314 break;
1315
1316 case JVM_CONSTANT_Float:
1317 assert(cache_index == _no_index_sentinel, "should not have been set");
1318 prim_value.f = this_cp->float_at(cp_index);
1319 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1320 break;
1321
1322 case JVM_CONSTANT_Long:
1323 assert(cache_index == _no_index_sentinel, "should not have been set");
1324 prim_value.j = this_cp->long_at(cp_index);
1325 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1326 break;
1327
1328 case JVM_CONSTANT_Double:
1329 assert(cache_index == _no_index_sentinel, "should not have been set");
1330 prim_value.d = this_cp->double_at(cp_index);
1331 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1332 break;
1333
1334 case JVM_CONSTANT_UnresolvedClassInError:
1335 case JVM_CONSTANT_DynamicInError:
1336 case JVM_CONSTANT_MethodHandleInError:
1337 case JVM_CONSTANT_MethodTypeInError:
1338 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1339 break;
1340
1341 default:
1342 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1343 break;
1344 }
1345
1346 if (cache_index >= 0) {
1347 // Benign race condition: resolved_references may already be filled in.
1348 // The important thing here is that all threads pick up the same result.
1349 // It doesn't matter which racing thread wins, as long as only one
1350 // result is used by all threads, and all future queries.
1351 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1352 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1353 if (old_result == nullptr) {
1354 return result_oop; // was installed
1355 } else {
1356 // Return the winning thread's result. This can be different than
1357 // the result here for MethodHandles.
1358 if (old_result == Universe::the_null_sentinel())
1359 old_result = nullptr;
1360 return old_result;
1361 }
1362 } else {
1363 assert(result_oop != Universe::the_null_sentinel(), "");
1364 return result_oop;
1365 }
1366 }
1367
1368 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1369 Symbol* sym = unresolved_string_at(cp_index);
1370 oop str = StringTable::intern(sym, CHECK_(nullptr));
1371 assert(java_lang_String::is_instance(str), "must be string");
1372 return str;
1373 }
1374
1375 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1376 int start_arg, int end_arg,
1377 objArrayHandle info, int pos,
1378 bool must_resolve, Handle if_not_available,
1379 TRAPS) {
1380 int limit = pos + end_arg - start_arg;
1381 // checks: cp_index in range [0..this_cp->length),
1382 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1383 // info array non-null, pos..limit in [0..info.length]
1384 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1385 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1386 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1387 (0 > start_arg || start_arg > end_arg) ||
1388 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1389 (0 > pos || pos > limit) ||
1390 (info.is_null() || limit > info->length())) {
1391 // An index or something else went wrong; throw an error.
1392 // Since this is an internal API, we don't expect this,
1393 // so we don't bother to craft a nice message.
1394 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1395 }
1396 // now we can loop safely
1397 int info_i = pos;
1398 for (int i = start_arg; i < end_arg; i++) {
1399 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1400 oop arg_oop;
1401 if (must_resolve) {
1402 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1403 } else {
1404 bool found_it = false;
1405 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1406 if (!found_it) arg_oop = if_not_available();
1407 }
1408 info->obj_at_put(info_i++, arg_oop);
1409 }
1410 }
1411
1412 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1413 // If the string has already been interned, this entry will be non-null
1414 oop str = this_cp->resolved_reference_at(obj_index);
1415 assert(str != Universe::the_null_sentinel(), "");
1416 if (str != nullptr) return str;
1417 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1418 str = StringTable::intern(sym, CHECK_(nullptr));
1419 this_cp->string_at_put(obj_index, str);
1420 assert(java_lang_String::is_instance(str), "must be string");
1421 return str;
1422 }
1423
1424
1425 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1426 // Names are interned, so we can compare Symbol*s directly
1427 Symbol* cp_name = klass_name_at(cp_index);
1428 return (cp_name == k->name());
1429 }
1430
1431
1432 // Iterate over symbols and decrement ones which are Symbol*s
1433 // This is done during GC.
1434 // Only decrement the UTF8 symbols. Strings point to
1435 // these symbols but didn't increment the reference count.
1436 void ConstantPool::unreference_symbols() {
1437 for (int index = 1; index < length(); index++) { // Index 0 is unused
1438 constantTag tag = tag_at(index);
1439 if (tag.is_symbol()) {
1440 symbol_at(index)->decrement_refcount();
1441 }
1442 }
1443 }
1444
1445
1446 // Compare this constant pool's entry at index1 to the constant pool
1447 // cp2's entry at index2.
1448 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1449 int index2) {
1450
1451 // The error tags are equivalent to non-error tags when comparing
1452 jbyte t1 = tag_at(index1).non_error_value();
1453 jbyte t2 = cp2->tag_at(index2).non_error_value();
1454
1455 // Some classes are pre-resolved (like Throwable) which may lead to
1456 // consider it as a different entry. We then revert them back temporarily
1457 // to ensure proper comparison.
1458 if (t1 == JVM_CONSTANT_Class) {
1459 t1 = JVM_CONSTANT_UnresolvedClass;
1460 }
1461 if (t2 == JVM_CONSTANT_Class) {
1462 t2 = JVM_CONSTANT_UnresolvedClass;
1463 }
1464
1465 if (t1 != t2) {
1466 // Not the same entry type so there is nothing else to check. Note
1467 // that this style of checking will consider resolved/unresolved
1468 // class pairs as different.
1469 // From the ConstantPool* API point of view, this is correct
1470 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1471 // plays out in the context of ConstantPool* merging.
1472 return false;
1473 }
1474
1475 switch (t1) {
1476 case JVM_CONSTANT_ClassIndex:
1477 {
1478 int recur1 = klass_index_at(index1);
1479 int recur2 = cp2->klass_index_at(index2);
1480 if (compare_entry_to(recur1, cp2, recur2)) {
1481 return true;
1482 }
1483 } break;
1484
1485 case JVM_CONSTANT_Double:
1486 {
1487 jdouble d1 = double_at(index1);
1488 jdouble d2 = cp2->double_at(index2);
1489 if (d1 == d2) {
1490 return true;
1491 }
1492 } break;
1493
1494 case JVM_CONSTANT_Fieldref:
1495 case JVM_CONSTANT_InterfaceMethodref:
1496 case JVM_CONSTANT_Methodref:
1497 {
1498 int recur1 = uncached_klass_ref_index_at(index1);
1499 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1500 bool match = compare_entry_to(recur1, cp2, recur2);
1501 if (match) {
1502 recur1 = uncached_name_and_type_ref_index_at(index1);
1503 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1504 if (compare_entry_to(recur1, cp2, recur2)) {
1505 return true;
1506 }
1507 }
1508 } break;
1509
1510 case JVM_CONSTANT_Float:
1511 {
1512 jfloat f1 = float_at(index1);
1513 jfloat f2 = cp2->float_at(index2);
1514 if (f1 == f2) {
1515 return true;
1516 }
1517 } break;
1518
1519 case JVM_CONSTANT_Integer:
1520 {
1521 jint i1 = int_at(index1);
1522 jint i2 = cp2->int_at(index2);
1523 if (i1 == i2) {
1524 return true;
1525 }
1526 } break;
1527
1528 case JVM_CONSTANT_Long:
1529 {
1530 jlong l1 = long_at(index1);
1531 jlong l2 = cp2->long_at(index2);
1532 if (l1 == l2) {
1533 return true;
1534 }
1535 } break;
1536
1537 case JVM_CONSTANT_NameAndType:
1538 {
1539 int recur1 = name_ref_index_at(index1);
1540 int recur2 = cp2->name_ref_index_at(index2);
1541 if (compare_entry_to(recur1, cp2, recur2)) {
1542 recur1 = signature_ref_index_at(index1);
1543 recur2 = cp2->signature_ref_index_at(index2);
1544 if (compare_entry_to(recur1, cp2, recur2)) {
1545 return true;
1546 }
1547 }
1548 } break;
1549
1550 case JVM_CONSTANT_StringIndex:
1551 {
1552 int recur1 = string_index_at(index1);
1553 int recur2 = cp2->string_index_at(index2);
1554 if (compare_entry_to(recur1, cp2, recur2)) {
1555 return true;
1556 }
1557 } break;
1558
1559 case JVM_CONSTANT_UnresolvedClass:
1560 {
1561 Symbol* k1 = klass_name_at(index1);
1562 Symbol* k2 = cp2->klass_name_at(index2);
1563 if (k1 == k2) {
1564 return true;
1565 }
1566 } break;
1567
1568 case JVM_CONSTANT_MethodType:
1569 {
1570 int k1 = method_type_index_at(index1);
1571 int k2 = cp2->method_type_index_at(index2);
1572 if (compare_entry_to(k1, cp2, k2)) {
1573 return true;
1574 }
1575 } break;
1576
1577 case JVM_CONSTANT_MethodHandle:
1578 {
1579 int k1 = method_handle_ref_kind_at(index1);
1580 int k2 = cp2->method_handle_ref_kind_at(index2);
1581 if (k1 == k2) {
1582 int i1 = method_handle_index_at(index1);
1583 int i2 = cp2->method_handle_index_at(index2);
1584 if (compare_entry_to(i1, cp2, i2)) {
1585 return true;
1586 }
1587 }
1588 } break;
1589
1590 case JVM_CONSTANT_Dynamic:
1591 {
1592 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1593 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1594 int i1 = bootstrap_methods_attribute_index(index1);
1595 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1596 bool match_entry = compare_entry_to(k1, cp2, k2);
1597 bool match_operand = compare_operand_to(i1, cp2, i2);
1598 return (match_entry && match_operand);
1599 } break;
1600
1601 case JVM_CONSTANT_InvokeDynamic:
1602 {
1603 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1604 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1605 int i1 = bootstrap_methods_attribute_index(index1);
1606 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1607 bool match_entry = compare_entry_to(k1, cp2, k2);
1608 bool match_operand = compare_operand_to(i1, cp2, i2);
1609 return (match_entry && match_operand);
1610 } break;
1611
1612 case JVM_CONSTANT_String:
1613 {
1614 Symbol* s1 = unresolved_string_at(index1);
1615 Symbol* s2 = cp2->unresolved_string_at(index2);
1616 if (s1 == s2) {
1617 return true;
1618 }
1619 } break;
1620
1621 case JVM_CONSTANT_Utf8:
1622 {
1623 Symbol* s1 = symbol_at(index1);
1624 Symbol* s2 = cp2->symbol_at(index2);
1625 if (s1 == s2) {
1626 return true;
1627 }
1628 } break;
1629
1630 // Invalid is used as the tag for the second constant pool entry
1631 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1632 // not be seen by itself.
1633 case JVM_CONSTANT_Invalid: // fall through
1634
1635 default:
1636 ShouldNotReachHere();
1637 break;
1638 }
1639
1640 return false;
1641 } // end compare_entry_to()
1642
1643
1644 // Resize the operands array with delta_len and delta_size.
1645 // Used in RedefineClasses for CP merge.
1646 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1647 int old_len = operand_array_length(operands());
1648 int new_len = old_len + delta_len;
1649 int min_len = (delta_len > 0) ? old_len : new_len;
1650
1651 int old_size = operands()->length();
1652 int new_size = old_size + delta_size;
1653 int min_size = (delta_size > 0) ? old_size : new_size;
1654
1655 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1656 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1657
1658 // Set index in the resized array for existing elements only
1659 for (int idx = 0; idx < min_len; idx++) {
1660 int offset = operand_offset_at(idx); // offset in original array
1661 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1662 }
1663 // Copy the bootstrap specifiers only
1664 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1665 new_ops->adr_at(2*new_len),
1666 (min_size - 2*min_len) * sizeof(u2));
1667 // Explicitly deallocate old operands array.
1668 // Note, it is not needed for 7u backport.
1669 if ( operands() != nullptr) { // the safety check
1670 MetadataFactory::free_array<u2>(loader_data, operands());
1671 }
1672 set_operands(new_ops);
1673 } // end resize_operands()
1674
1675
1676 // Extend the operands array with the length and size of the ext_cp operands.
1677 // Used in RedefineClasses for CP merge.
1678 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1679 int delta_len = operand_array_length(ext_cp->operands());
1680 if (delta_len == 0) {
1681 return; // nothing to do
1682 }
1683 int delta_size = ext_cp->operands()->length();
1684
1685 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1686
1687 if (operand_array_length(operands()) == 0) {
1688 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1689 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1690 // The first element index defines the offset of second part
1691 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1692 set_operands(new_ops);
1693 } else {
1694 resize_operands(delta_len, delta_size, CHECK);
1695 }
1696
1697 } // end extend_operands()
1698
1699
1700 // Shrink the operands array to a smaller array with new_len length.
1701 // Used in RedefineClasses for CP merge.
1702 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1703 int old_len = operand_array_length(operands());
1704 if (new_len == old_len) {
1705 return; // nothing to do
1706 }
1707 assert(new_len < old_len, "shrunken operands array must be smaller");
1708
1709 int free_base = operand_next_offset_at(new_len - 1);
1710 int delta_len = new_len - old_len;
1711 int delta_size = 2*delta_len + free_base - operands()->length();
1712
1713 resize_operands(delta_len, delta_size, CHECK);
1714
1715 } // end shrink_operands()
1716
1717
1718 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1719 const constantPoolHandle& to_cp,
1720 TRAPS) {
1721
1722 int from_oplen = operand_array_length(from_cp->operands());
1723 int old_oplen = operand_array_length(to_cp->operands());
1724 if (from_oplen != 0) {
1725 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1726 // append my operands to the target's operands array
1727 if (old_oplen == 0) {
1728 // Can't just reuse from_cp's operand list because of deallocation issues
1729 int len = from_cp->operands()->length();
1730 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1731 Copy::conjoint_memory_atomic(
1732 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1733 to_cp->set_operands(new_ops);
1734 } else {
1735 int old_len = to_cp->operands()->length();
1736 int from_len = from_cp->operands()->length();
1737 int old_off = old_oplen * sizeof(u2);
1738 int from_off = from_oplen * sizeof(u2);
1739 // Use the metaspace for the destination constant pool
1740 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1741 int fillp = 0, len = 0;
1742 // first part of dest
1743 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1744 new_operands->adr_at(fillp),
1745 (len = old_off) * sizeof(u2));
1746 fillp += len;
1747 // first part of src
1748 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1749 new_operands->adr_at(fillp),
1750 (len = from_off) * sizeof(u2));
1751 fillp += len;
1752 // second part of dest
1753 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1754 new_operands->adr_at(fillp),
1755 (len = old_len - old_off) * sizeof(u2));
1756 fillp += len;
1757 // second part of src
1758 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1759 new_operands->adr_at(fillp),
1760 (len = from_len - from_off) * sizeof(u2));
1761 fillp += len;
1762 assert(fillp == new_operands->length(), "");
1763
1764 // Adjust indexes in the first part of the copied operands array.
1765 for (int j = 0; j < from_oplen; j++) {
1766 int offset = operand_offset_at(new_operands, old_oplen + j);
1767 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1768 offset += old_len; // every new tuple is preceded by old_len extra u2's
1769 operand_offset_at_put(new_operands, old_oplen + j, offset);
1770 }
1771
1772 // replace target operands array with combined array
1773 to_cp->set_operands(new_operands);
1774 }
1775 }
1776 } // end copy_operands()
1777
1778
1779 // Copy this constant pool's entries at start_i to end_i (inclusive)
1780 // to the constant pool to_cp's entries starting at to_i. A total of
1781 // (end_i - start_i) + 1 entries are copied.
1782 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1783 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1784
1785
1786 int dest_cpi = to_i; // leave original alone for debug purposes
1787
1788 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1789 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1790
1791 switch (from_cp->tag_at(src_cpi).value()) {
1792 case JVM_CONSTANT_Double:
1793 case JVM_CONSTANT_Long:
1794 // double and long take two constant pool entries
1795 src_cpi += 2;
1796 dest_cpi += 2;
1797 break;
1798
1799 default:
1800 // all others take one constant pool entry
1801 src_cpi++;
1802 dest_cpi++;
1803 break;
1804 }
1805 }
1806 copy_operands(from_cp, to_cp, CHECK);
1807
1808 } // end copy_cp_to_impl()
1809
1810
1811 // Copy this constant pool's entry at from_i to the constant pool
1812 // to_cp's entry at to_i.
1813 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1814 const constantPoolHandle& to_cp, int to_i) {
1815
1816 int tag = from_cp->tag_at(from_i).value();
1817 switch (tag) {
1818 case JVM_CONSTANT_ClassIndex:
1819 {
1820 jint ki = from_cp->klass_index_at(from_i);
1821 to_cp->klass_index_at_put(to_i, ki);
1822 } break;
1823
1824 case JVM_CONSTANT_Double:
1825 {
1826 jdouble d = from_cp->double_at(from_i);
1827 to_cp->double_at_put(to_i, d);
1828 // double takes two constant pool entries so init second entry's tag
1829 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1830 } break;
1831
1832 case JVM_CONSTANT_Fieldref:
1833 {
1834 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1835 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1836 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1837 } break;
1838
1839 case JVM_CONSTANT_Float:
1840 {
1841 jfloat f = from_cp->float_at(from_i);
1842 to_cp->float_at_put(to_i, f);
1843 } break;
1844
1845 case JVM_CONSTANT_Integer:
1846 {
1847 jint i = from_cp->int_at(from_i);
1848 to_cp->int_at_put(to_i, i);
1849 } break;
1850
1851 case JVM_CONSTANT_InterfaceMethodref:
1852 {
1853 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1854 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1855 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1856 } break;
1857
1858 case JVM_CONSTANT_Long:
1859 {
1860 jlong l = from_cp->long_at(from_i);
1861 to_cp->long_at_put(to_i, l);
1862 // long takes two constant pool entries so init second entry's tag
1863 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1864 } break;
1865
1866 case JVM_CONSTANT_Methodref:
1867 {
1868 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1869 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1870 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1871 } break;
1872
1873 case JVM_CONSTANT_NameAndType:
1874 {
1875 int name_ref_index = from_cp->name_ref_index_at(from_i);
1876 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1877 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1878 } break;
1879
1880 case JVM_CONSTANT_StringIndex:
1881 {
1882 jint si = from_cp->string_index_at(from_i);
1883 to_cp->string_index_at_put(to_i, si);
1884 } break;
1885
1886 case JVM_CONSTANT_Class:
1887 case JVM_CONSTANT_UnresolvedClass:
1888 case JVM_CONSTANT_UnresolvedClassInError:
1889 {
1890 // Revert to JVM_CONSTANT_ClassIndex
1891 int name_index = from_cp->klass_slot_at(from_i).name_index();
1892 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1893 to_cp->klass_index_at_put(to_i, name_index);
1894 } break;
1895
1896 case JVM_CONSTANT_String:
1897 {
1898 Symbol* s = from_cp->unresolved_string_at(from_i);
1899 to_cp->unresolved_string_at_put(to_i, s);
1900 } break;
1901
1902 case JVM_CONSTANT_Utf8:
1903 {
1904 Symbol* s = from_cp->symbol_at(from_i);
1905 // Need to increase refcount, the old one will be thrown away and deferenced
1906 s->increment_refcount();
1907 to_cp->symbol_at_put(to_i, s);
1908 } break;
1909
1910 case JVM_CONSTANT_MethodType:
1911 case JVM_CONSTANT_MethodTypeInError:
1912 {
1913 jint k = from_cp->method_type_index_at(from_i);
1914 to_cp->method_type_index_at_put(to_i, k);
1915 } break;
1916
1917 case JVM_CONSTANT_MethodHandle:
1918 case JVM_CONSTANT_MethodHandleInError:
1919 {
1920 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1921 int k2 = from_cp->method_handle_index_at(from_i);
1922 to_cp->method_handle_index_at_put(to_i, k1, k2);
1923 } break;
1924
1925 case JVM_CONSTANT_Dynamic:
1926 case JVM_CONSTANT_DynamicInError:
1927 {
1928 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1929 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1930 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1931 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1932 } break;
1933
1934 case JVM_CONSTANT_InvokeDynamic:
1935 {
1936 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1937 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1938 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1939 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1940 } break;
1941
1942 // Invalid is used as the tag for the second constant pool entry
1943 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1944 // not be seen by itself.
1945 case JVM_CONSTANT_Invalid: // fall through
1946
1947 default:
1948 {
1949 ShouldNotReachHere();
1950 } break;
1951 }
1952 } // end copy_entry_to()
1953
1954 // Search constant pool search_cp for an entry that matches this
1955 // constant pool's entry at pattern_i. Returns the index of a
1956 // matching entry or zero (0) if there is no matching entry.
1957 int ConstantPool::find_matching_entry(int pattern_i,
1958 const constantPoolHandle& search_cp) {
1959
1960 // index zero (0) is not used
1961 for (int i = 1; i < search_cp->length(); i++) {
1962 bool found = compare_entry_to(pattern_i, search_cp, i);
1963 if (found) {
1964 return i;
1965 }
1966 }
1967
1968 return 0; // entry not found; return unused index zero (0)
1969 } // end find_matching_entry()
1970
1971
1972 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1973 // cp2's bootstrap specifier at idx2.
1974 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2) {
1975 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1976 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1977 bool match = compare_entry_to(k1, cp2, k2);
1978
1979 if (!match) {
1980 return false;
1981 }
1982 int argc = operand_argument_count_at(idx1);
1983 if (argc == cp2->operand_argument_count_at(idx2)) {
1984 for (int j = 0; j < argc; j++) {
1985 k1 = operand_argument_index_at(idx1, j);
1986 k2 = cp2->operand_argument_index_at(idx2, j);
1987 match = compare_entry_to(k1, cp2, k2);
1988 if (!match) {
1989 return false;
1990 }
1991 }
1992 return true; // got through loop; all elements equal
1993 }
1994 return false;
1995 } // end compare_operand_to()
1996
1997 // Search constant pool search_cp for a bootstrap specifier that matches
1998 // this constant pool's bootstrap specifier data at pattern_i index.
1999 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
2000 int ConstantPool::find_matching_operand(int pattern_i,
2001 const constantPoolHandle& search_cp, int search_len) {
2002 for (int i = 0; i < search_len; i++) {
2003 bool found = compare_operand_to(pattern_i, search_cp, i);
2004 if (found) {
2005 return i;
2006 }
2007 }
2008 return -1; // bootstrap specifier data not found; return unused index (-1)
2009 } // end find_matching_operand()
2010
2011
2012 #ifndef PRODUCT
2013
2014 const char* ConstantPool::printable_name_at(int cp_index) {
2015
2016 constantTag tag = tag_at(cp_index);
2017
2018 if (tag.is_string()) {
2019 return string_at_noresolve(cp_index);
2020 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
2021 return klass_name_at(cp_index)->as_C_string();
2022 } else if (tag.is_symbol()) {
2023 return symbol_at(cp_index)->as_C_string();
2024 }
2025 return "";
2026 }
2027
2028 #endif // PRODUCT
2029
2030
2031 // Returns size of constant pool entry.
2032 jint ConstantPool::cpool_entry_size(jint idx) {
2033 switch(tag_at(idx).value()) {
2034 case JVM_CONSTANT_Invalid:
2035 case JVM_CONSTANT_Unicode:
2036 return 1;
2037
2038 case JVM_CONSTANT_Utf8:
2039 return 3 + symbol_at(idx)->utf8_length();
2040
2041 case JVM_CONSTANT_Class:
2042 case JVM_CONSTANT_String:
2043 case JVM_CONSTANT_ClassIndex:
2044 case JVM_CONSTANT_UnresolvedClass:
2045 case JVM_CONSTANT_UnresolvedClassInError:
2046 case JVM_CONSTANT_StringIndex:
2047 case JVM_CONSTANT_MethodType:
2048 case JVM_CONSTANT_MethodTypeInError:
2049 return 3;
2050
2051 case JVM_CONSTANT_MethodHandle:
2052 case JVM_CONSTANT_MethodHandleInError:
2053 return 4; //tag, ref_kind, ref_index
2054
2055 case JVM_CONSTANT_Integer:
2056 case JVM_CONSTANT_Float:
2057 case JVM_CONSTANT_Fieldref:
2058 case JVM_CONSTANT_Methodref:
2059 case JVM_CONSTANT_InterfaceMethodref:
2060 case JVM_CONSTANT_NameAndType:
2061 return 5;
2062
2063 case JVM_CONSTANT_Dynamic:
2064 case JVM_CONSTANT_DynamicInError:
2065 case JVM_CONSTANT_InvokeDynamic:
2066 // u1 tag, u2 bsm, u2 nt
2067 return 5;
2068
2069 case JVM_CONSTANT_Long:
2070 case JVM_CONSTANT_Double:
2071 return 9;
2072 }
2073 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2074 return 1;
2075 } /* end cpool_entry_size */
2076
2077
2078 // SymbolHash is used to find a constant pool index from a string.
2079 // This function fills in SymbolHashs, one for utf8s and one for
2080 // class names, returns size of the cpool raw bytes.
2081 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
2082 SymbolHash *classmap) {
2083 jint size = 0;
2084
2085 for (u2 idx = 1; idx < length(); idx++) {
2086 u2 tag = tag_at(idx).value();
2087 size += cpool_entry_size(idx);
2088
2089 switch(tag) {
2090 case JVM_CONSTANT_Utf8: {
2091 Symbol* sym = symbol_at(idx);
2092 symmap->add_if_absent(sym, idx);
2093 break;
2094 }
2095 case JVM_CONSTANT_Class:
2096 case JVM_CONSTANT_UnresolvedClass:
2097 case JVM_CONSTANT_UnresolvedClassInError: {
2098 Symbol* sym = klass_name_at(idx);
2099 classmap->add_if_absent(sym, idx);
2100 break;
2101 }
2102 case JVM_CONSTANT_Long:
2103 case JVM_CONSTANT_Double: {
2104 idx++; // Both Long and Double take two cpool slots
2105 break;
2106 }
2107 }
2108 }
2109 return size;
2110 } /* end hash_utf8_entries_to */
2111
2112
2113 // Copy cpool bytes.
2114 // Returns:
2115 // 0, in case of OutOfMemoryError
2116 // -1, in case of internal error
2117 // > 0, count of the raw cpool bytes that have been copied
2118 int ConstantPool::copy_cpool_bytes(int cpool_size,
2119 SymbolHash* tbl,
2120 unsigned char *bytes) {
2121 u2 idx1, idx2;
2122 jint size = 0;
2123 jint cnt = length();
2124 unsigned char *start_bytes = bytes;
2125
2126 for (jint idx = 1; idx < cnt; idx++) {
2127 u1 tag = tag_at(idx).value();
2128 jint ent_size = cpool_entry_size(idx);
2129
2130 assert(size + ent_size <= cpool_size, "Size mismatch");
2131
2132 *bytes = tag;
2133 switch(tag) {
2134 case JVM_CONSTANT_Invalid: {
2135 break;
2136 }
2137 case JVM_CONSTANT_Unicode: {
2138 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2139 break;
2140 }
2141 case JVM_CONSTANT_Utf8: {
2142 Symbol* sym = symbol_at(idx);
2143 char* str = sym->as_utf8();
2144 // Warning! It's crashing on x86 with len = sym->utf8_length()
2145 int len = (int) strlen(str);
2146 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2147 for (int i = 0; i < len; i++) {
2148 bytes[3+i] = (u1) str[i];
2149 }
2150 break;
2151 }
2152 case JVM_CONSTANT_Integer: {
2153 jint val = int_at(idx);
2154 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2155 break;
2156 }
2157 case JVM_CONSTANT_Float: {
2158 jfloat val = float_at(idx);
2159 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2160 break;
2161 }
2162 case JVM_CONSTANT_Long: {
2163 jlong val = long_at(idx);
2164 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2165 idx++; // Long takes two cpool slots
2166 break;
2167 }
2168 case JVM_CONSTANT_Double: {
2169 jdouble val = double_at(idx);
2170 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2171 idx++; // Double takes two cpool slots
2172 break;
2173 }
2174 case JVM_CONSTANT_Class:
2175 case JVM_CONSTANT_UnresolvedClass:
2176 case JVM_CONSTANT_UnresolvedClassInError: {
2177 *bytes = JVM_CONSTANT_Class;
2178 Symbol* sym = klass_name_at(idx);
2179 idx1 = tbl->symbol_to_value(sym);
2180 assert(idx1 != 0, "Have not found a hashtable entry");
2181 Bytes::put_Java_u2((address) (bytes+1), idx1);
2182 break;
2183 }
2184 case JVM_CONSTANT_String: {
2185 *bytes = JVM_CONSTANT_String;
2186 Symbol* sym = unresolved_string_at(idx);
2187 idx1 = tbl->symbol_to_value(sym);
2188 assert(idx1 != 0, "Have not found a hashtable entry");
2189 Bytes::put_Java_u2((address) (bytes+1), idx1);
2190 break;
2191 }
2192 case JVM_CONSTANT_Fieldref:
2193 case JVM_CONSTANT_Methodref:
2194 case JVM_CONSTANT_InterfaceMethodref: {
2195 idx1 = uncached_klass_ref_index_at(idx);
2196 idx2 = uncached_name_and_type_ref_index_at(idx);
2197 Bytes::put_Java_u2((address) (bytes+1), idx1);
2198 Bytes::put_Java_u2((address) (bytes+3), idx2);
2199 break;
2200 }
2201 case JVM_CONSTANT_NameAndType: {
2202 idx1 = name_ref_index_at(idx);
2203 idx2 = signature_ref_index_at(idx);
2204 Bytes::put_Java_u2((address) (bytes+1), idx1);
2205 Bytes::put_Java_u2((address) (bytes+3), idx2);
2206 break;
2207 }
2208 case JVM_CONSTANT_ClassIndex: {
2209 *bytes = JVM_CONSTANT_Class;
2210 idx1 = checked_cast<u2>(klass_index_at(idx));
2211 Bytes::put_Java_u2((address) (bytes+1), idx1);
2212 break;
2213 }
2214 case JVM_CONSTANT_StringIndex: {
2215 *bytes = JVM_CONSTANT_String;
2216 idx1 = checked_cast<u2>(string_index_at(idx));
2217 Bytes::put_Java_u2((address) (bytes+1), idx1);
2218 break;
2219 }
2220 case JVM_CONSTANT_MethodHandle:
2221 case JVM_CONSTANT_MethodHandleInError: {
2222 *bytes = JVM_CONSTANT_MethodHandle;
2223 int kind = method_handle_ref_kind_at(idx);
2224 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2225 *(bytes+1) = (unsigned char) kind;
2226 Bytes::put_Java_u2((address) (bytes+2), idx1);
2227 break;
2228 }
2229 case JVM_CONSTANT_MethodType:
2230 case JVM_CONSTANT_MethodTypeInError: {
2231 *bytes = JVM_CONSTANT_MethodType;
2232 idx1 = checked_cast<u2>(method_type_index_at(idx));
2233 Bytes::put_Java_u2((address) (bytes+1), idx1);
2234 break;
2235 }
2236 case JVM_CONSTANT_Dynamic:
2237 case JVM_CONSTANT_DynamicInError: {
2238 *bytes = tag;
2239 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2240 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2241 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2242 Bytes::put_Java_u2((address) (bytes+1), idx1);
2243 Bytes::put_Java_u2((address) (bytes+3), idx2);
2244 break;
2245 }
2246 case JVM_CONSTANT_InvokeDynamic: {
2247 *bytes = tag;
2248 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2249 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2250 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2251 Bytes::put_Java_u2((address) (bytes+1), idx1);
2252 Bytes::put_Java_u2((address) (bytes+3), idx2);
2253 break;
2254 }
2255 }
2256 bytes += ent_size;
2257 size += ent_size;
2258 }
2259 assert(size == cpool_size, "Size mismatch");
2260
2261 return (int)(bytes - start_bytes);
2262 } /* end copy_cpool_bytes */
2263
2264 bool ConstantPool::is_maybe_on_stack() const {
2265 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2266 if (!Continuations::enabled()) {
2267 return false;
2268 }
2269
2270 // If the condition below is true, it means that the nmethod was found to
2271 // be alive the previous completed marking cycle.
2272 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2273 }
2274
2275 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2276 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2277 // memory for the method is reclaimed.
2278 bool ConstantPool::on_stack() const {
2279 if ((_flags &_on_stack) != 0) {
2280 return true;
2281 }
2282
2283 if (_cache == nullptr) {
2284 return false;
2285 }
2286
2287 return is_maybe_on_stack();
2288 }
2289
2290 void ConstantPool::set_on_stack(const bool value) {
2291 if (value) {
2292 // Only record if it's not already set.
2293 if (!on_stack()) {
2294 assert(!is_shared(), "should always be set for shared constant pools");
2295 _flags |= _on_stack;
2296 MetadataOnStackMark::record(this);
2297 }
2298 } else {
2299 // Clearing is done single-threadedly.
2300 if (!is_shared()) {
2301 _flags &= (u2)(~_on_stack);
2302 }
2303 }
2304 }
2305
2306 // Printing
2307
2308 void ConstantPool::print_on(outputStream* st) const {
2309 assert(is_constantPool(), "must be constantPool");
2310 st->print_cr("%s", internal_name());
2311 if (flags() != 0) {
2312 st->print(" - flags: 0x%x", flags());
2313 if (has_preresolution()) st->print(" has_preresolution");
2314 if (on_stack()) st->print(" on_stack");
2315 st->cr();
2316 }
2317 if (pool_holder() != nullptr) {
2318 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2319 }
2320 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2321 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2322 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2323 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2324 st->print_cr(" - cp length: %d", length());
2325
2326 for (int index = 1; index < length(); index++) { // Index 0 is unused
2327 ((ConstantPool*)this)->print_entry_on(index, st);
2328 switch (tag_at(index).value()) {
2329 case JVM_CONSTANT_Long :
2330 case JVM_CONSTANT_Double :
2331 index++; // Skip entry following eigth-byte constant
2332 }
2333
2334 }
2335 st->cr();
2336 }
2337
2338 // Print one constant pool entry
2339 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2340 EXCEPTION_MARK;
2341 st->print(" - %3d : ", cp_index);
2342 tag_at(cp_index).print_on(st);
2343 st->print(" : ");
2344 switch (tag_at(cp_index).value()) {
2345 case JVM_CONSTANT_Class :
2346 { Klass* k = klass_at(cp_index, CATCH);
2347 guarantee(k != nullptr, "need klass");
2348 k->print_value_on(st);
2349 st->print(" {" PTR_FORMAT "}", p2i(k));
2350 }
2351 break;
2352 case JVM_CONSTANT_Fieldref :
2353 case JVM_CONSTANT_Methodref :
2354 case JVM_CONSTANT_InterfaceMethodref :
2355 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2356 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2357 break;
2358 case JVM_CONSTANT_String :
2359 unresolved_string_at(cp_index)->print_value_on(st);
2360 break;
2361 case JVM_CONSTANT_Integer :
2362 st->print("%d", int_at(cp_index));
2363 break;
2364 case JVM_CONSTANT_Float :
2365 st->print("%f", float_at(cp_index));
2366 break;
2367 case JVM_CONSTANT_Long :
2368 st->print_jlong(long_at(cp_index));
2369 break;
2370 case JVM_CONSTANT_Double :
2371 st->print("%lf", double_at(cp_index));
2372 break;
2373 case JVM_CONSTANT_NameAndType :
2374 st->print("name_index=%d", name_ref_index_at(cp_index));
2375 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2376 break;
2377 case JVM_CONSTANT_Utf8 :
2378 symbol_at(cp_index)->print_value_on(st);
2379 break;
2380 case JVM_CONSTANT_ClassIndex: {
2381 int name_index = *int_at_addr(cp_index);
2382 st->print("klass_index=%d ", name_index);
2383 symbol_at(name_index)->print_value_on(st);
2384 }
2385 break;
2386 case JVM_CONSTANT_UnresolvedClass : // fall-through
2387 case JVM_CONSTANT_UnresolvedClassInError: {
2388 CPKlassSlot kslot = klass_slot_at(cp_index);
2389 int resolved_klass_index = kslot.resolved_klass_index();
2390 int name_index = kslot.name_index();
2391 assert(tag_at(name_index).is_symbol(), "sanity");
2392 symbol_at(name_index)->print_value_on(st);
2393 }
2394 break;
2395 case JVM_CONSTANT_MethodHandle :
2396 case JVM_CONSTANT_MethodHandleInError :
2397 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2398 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2399 break;
2400 case JVM_CONSTANT_MethodType :
2401 case JVM_CONSTANT_MethodTypeInError :
2402 st->print("signature_index=%d", method_type_index_at(cp_index));
2403 break;
2404 case JVM_CONSTANT_Dynamic :
2405 case JVM_CONSTANT_DynamicInError :
2406 {
2407 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2408 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2409 int argc = bootstrap_argument_count_at(cp_index);
2410 if (argc > 0) {
2411 for (int arg_i = 0; arg_i < argc; arg_i++) {
2412 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2413 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2414 }
2415 st->print("}");
2416 }
2417 }
2418 break;
2419 case JVM_CONSTANT_InvokeDynamic :
2420 {
2421 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2422 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2423 int argc = bootstrap_argument_count_at(cp_index);
2424 if (argc > 0) {
2425 for (int arg_i = 0; arg_i < argc; arg_i++) {
2426 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2427 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2428 }
2429 st->print("}");
2430 }
2431 }
2432 break;
2433 default:
2434 ShouldNotReachHere();
2435 break;
2436 }
2437 st->cr();
2438 }
2439
2440 void ConstantPool::print_value_on(outputStream* st) const {
2441 assert(is_constantPool(), "must be constantPool");
2442 st->print("constant pool [%d]", length());
2443 if (has_preresolution()) st->print("/preresolution");
2444 if (operands() != nullptr) st->print("/operands[%d]", operands()->length());
2445 print_address_on(st);
2446 if (pool_holder() != nullptr) {
2447 st->print(" for ");
2448 pool_holder()->print_value_on(st);
2449 bool extra = (pool_holder()->constants() != this);
2450 if (extra) st->print(" (extra)");
2451 }
2452 if (cache() != nullptr) {
2453 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2454 }
2455 }
2456
2457 // Verification
2458
2459 void ConstantPool::verify_on(outputStream* st) {
2460 guarantee(is_constantPool(), "object must be constant pool");
2461 for (int i = 0; i< length(); i++) {
2462 constantTag tag = tag_at(i);
2463 if (tag.is_klass() || tag.is_unresolved_klass()) {
2464 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2465 } else if (tag.is_symbol()) {
2466 Symbol* entry = symbol_at(i);
2467 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2468 } else if (tag.is_string()) {
2469 Symbol* entry = unresolved_string_at(i);
2470 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2471 }
2472 }
2473 if (pool_holder() != nullptr) {
2474 // Note: pool_holder() can be null in temporary constant pools
2475 // used during constant pool merging
2476 guarantee(pool_holder()->is_klass(), "should be klass");
2477 }
2478 }