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