1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotConstantPoolResolver.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/archiveHeapLoader.hpp"
28 #include "cds/archiveHeapWriter.hpp"
29 #include "cds/cdsConfig.hpp"
30 #include "cds/heapShared.hpp"
31 #include "classfile/classLoader.hpp"
32 #include "classfile/classLoaderData.hpp"
33 #include "classfile/javaClasses.inline.hpp"
34 #include "classfile/metadataOnStackMark.hpp"
35 #include "classfile/stringTable.hpp"
36 #include "classfile/systemDictionary.hpp"
37 #include "classfile/systemDictionaryShared.hpp"
38 #include "classfile/vmClasses.hpp"
39 #include "classfile/vmSymbols.hpp"
40 #include "code/codeCache.hpp"
41 #include "interpreter/bootstrapInfo.hpp"
42 #include "interpreter/linkResolver.hpp"
43 #include "jvm.h"
44 #include "logging/log.hpp"
45 #include "logging/logStream.hpp"
46 #include "memory/allocation.inline.hpp"
47 #include "memory/metadataFactory.hpp"
48 #include "memory/metaspaceClosure.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/array.hpp"
53 #include "oops/constantPool.inline.hpp"
54 #include "oops/cpCache.inline.hpp"
55 #include "oops/fieldStreams.inline.hpp"
56 #include "oops/instanceKlass.hpp"
57 #include "oops/klass.inline.hpp"
58 #include "oops/objArrayKlass.hpp"
59 #include "oops/objArrayOop.inline.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/typeArrayOop.inline.hpp"
62 #include "prims/jvmtiExport.hpp"
63 #include "runtime/atomic.hpp"
64 #include "runtime/fieldDescriptor.inline.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/init.hpp"
67 #include "runtime/javaCalls.hpp"
68 #include "runtime/javaThread.inline.hpp"
69 #include "runtime/perfData.hpp"
70 #include "runtime/signature.hpp"
71 #include "runtime/vframe.inline.hpp"
72 #include "utilities/checkedCast.hpp"
73 #include "utilities/copy.hpp"
74
75 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
76 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
77 int size = ConstantPool::size(length);
78 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
79 }
80
81 void ConstantPool::copy_fields(const ConstantPool* orig) {
82 // Preserve dynamic constant information from the original pool
83 if (orig->has_dynamic_constant()) {
84 set_has_dynamic_constant();
85 }
86
87 set_major_version(orig->major_version());
88 set_minor_version(orig->minor_version());
89
90 set_source_file_name_index(orig->source_file_name_index());
91 set_generic_signature_index(orig->generic_signature_index());
92 }
93
94 #ifdef ASSERT
95
96 // MetaspaceObj allocation invariant is calloc equivalent memory
97 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
98 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
99 assert(tags != nullptr, "invariant");
100 const int length = tags->length();
101 for (int index = 0; index < length; ++index) {
102 if (JVM_CONSTANT_Invalid != tags->at(index)) {
103 return false;
104 }
105 }
106 return true;
107 }
108
109 #endif
110
111 ConstantPool::ConstantPool() {
112 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
113 }
114
115 ConstantPool::ConstantPool(Array<u1>* tags) :
116 _tags(tags),
117 _length(tags->length()) {
118
119 assert(_tags != nullptr, "invariant");
120 assert(tags->length() == _length, "invariant");
121 assert(tag_array_is_zero_initialized(tags), "invariant");
122 assert(0 == flags(), "invariant");
123 assert(0 == version(), "invariant");
124 assert(nullptr == _pool_holder, "invariant");
125 }
126
127 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
128 if (cache() != nullptr) {
129 MetadataFactory::free_metadata(loader_data, cache());
130 set_cache(nullptr);
131 }
132
133 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
134 set_resolved_klasses(nullptr);
135
136 MetadataFactory::free_array<jushort>(loader_data, operands());
137 set_operands(nullptr);
138
139 release_C_heap_structures();
140
141 // free tag array
142 MetadataFactory::free_array<u1>(loader_data, tags());
143 set_tags(nullptr);
144 }
145
146 void ConstantPool::release_C_heap_structures() {
147 // walk constant pool and decrement symbol reference counts
148 unreference_symbols();
149 }
150
151 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
152 log_trace(cds)("Iter(ConstantPool): %p", this);
153
154 it->push(&_tags, MetaspaceClosure::_writable);
155 it->push(&_cache);
156 it->push(&_pool_holder);
157 it->push(&_operands);
158 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
159
160 for (int i = 0; i < length(); i++) {
161 // The only MSO's embedded in the CP entries are Symbols:
162 // JVM_CONSTANT_String
163 // JVM_CONSTANT_Utf8
164 constantTag ctag = tag_at(i);
165 if (ctag.is_string() || ctag.is_utf8()) {
166 it->push(symbol_at_addr(i));
167 }
168 }
169 }
170
171 objArrayOop ConstantPool::resolved_references() const {
172 return _cache->resolved_references();
173 }
174
175 // Called from outside constant pool resolution where a resolved_reference array
176 // may not be present.
177 objArrayOop ConstantPool::resolved_references_or_null() const {
178 if (_cache == nullptr) {
179 return nullptr;
180 } else {
181 return _cache->resolved_references();
182 }
183 }
184
185 oop ConstantPool::resolved_reference_at(int index) const {
186 oop result = resolved_references()->obj_at(index);
187 assert(oopDesc::is_oop_or_null(result), "Must be oop");
188 return result;
189 }
190
191 // Use a CAS for multithreaded access
192 oop ConstantPool::set_resolved_reference_at(int index, oop new_result) {
193 assert(oopDesc::is_oop_or_null(new_result), "Must be oop");
194 return resolved_references()->replace_if_null(index, new_result);
195 }
196
197 // Create resolved_references array and mapping array for original cp indexes
198 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
199 // to map it back for resolving and some unlikely miscellaneous uses.
200 // The objects created by invokedynamic are appended to this list.
201 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
202 const intStack& reference_map,
203 int constant_pool_map_length,
204 TRAPS) {
205 // Initialized the resolved object cache.
206 int map_length = reference_map.length();
207 if (map_length > 0) {
208 // Only need mapping back to constant pool entries. The map isn't used for
209 // invokedynamic resolved_reference entries. For invokedynamic entries,
210 // the constant pool cache index has the mapping back to both the constant
211 // pool and to the resolved reference index.
212 if (constant_pool_map_length > 0) {
213 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
214
215 for (int i = 0; i < constant_pool_map_length; i++) {
216 int x = reference_map.at(i);
217 assert(x == (int)(jushort) x, "klass index is too big");
218 om->at_put(i, (jushort)x);
219 }
220 set_reference_map(om);
221 }
222
223 // Create Java array for holding resolved strings, methodHandles,
224 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
225 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
226 HandleMark hm(THREAD);
227 Handle refs_handle (THREAD, stom); // must handleize.
228 set_resolved_references(loader_data->add_handle(refs_handle));
229
230 // Create a "scratch" copy of the resolved references array to archive
231 if (CDSConfig::is_dumping_heap()) {
232 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
233 HeapShared::add_scratch_resolved_references(this, scratch_references);
234 }
235 }
236 }
237
238 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
239 // A ConstantPool can't possibly have 0xffff valid class entries,
240 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
241 // entry for the class's name. So at most we will have 0xfffe class entries.
242 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
243 // UnresolvedKlass entries that are temporarily created during class redefinition.
244 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
245 assert(resolved_klasses() == nullptr, "sanity");
246 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
247 set_resolved_klasses(rk);
248 }
249
250 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
251 int len = length();
252 int num_klasses = 0;
253 for (int i = 1; i <len; i++) {
254 switch (tag_at(i).value()) {
255 case JVM_CONSTANT_ClassIndex:
256 {
257 const int class_index = klass_index_at(i);
258 unresolved_klass_at_put(i, class_index, num_klasses++);
259 }
260 break;
261 #ifndef PRODUCT
262 case JVM_CONSTANT_Class:
263 case JVM_CONSTANT_UnresolvedClass:
264 case JVM_CONSTANT_UnresolvedClassInError:
265 // All of these should have been reverted back to ClassIndex before calling
266 // this function.
267 ShouldNotReachHere();
268 #endif
269 }
270 }
271 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
272 }
273
274 // Hidden class support:
275 void ConstantPool::klass_at_put(int class_index, Klass* k) {
276 assert(k != nullptr, "must be valid klass");
277 CPKlassSlot kslot = klass_slot_at(class_index);
278 int resolved_klass_index = kslot.resolved_klass_index();
279 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
280 Atomic::release_store(adr, k);
281
282 // The interpreter assumes when the tag is stored, the klass is resolved
283 // and the Klass* non-null, so we need hardware store ordering here.
284 release_tag_at_put(class_index, JVM_CONSTANT_Class);
285 }
286
287 #if INCLUDE_CDS_JAVA_HEAP
288 template <typename Function>
289 void ConstantPool::iterate_archivable_resolved_references(Function function) {
290 objArrayOop rr = resolved_references();
291 if (rr != nullptr && cache() != nullptr && CDSConfig::is_dumping_method_handles()) {
292 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
293 if (indy_entries != nullptr) {
294 for (int i = 0; i < indy_entries->length(); i++) {
295 ResolvedIndyEntry *rie = indy_entries->adr_at(i);
296 if (rie->is_resolved() && AOTConstantPoolResolver::is_resolution_deterministic(this, rie->constant_pool_index())) {
297 int rr_index = rie->resolved_references_index();
298 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
299 function(rr_index);
300
301 // Save the BSM as well (sometimes the JIT looks up the BSM it for replay)
302 int indy_cp_index = rie->constant_pool_index();
303 int bsm_mh_cp_index = bootstrap_method_ref_index_at(indy_cp_index);
304 int bsm_rr_index = cp_to_object_index(bsm_mh_cp_index);
305 assert(resolved_reference_at(bsm_rr_index) != nullptr, "must exist");
306 function(bsm_rr_index);
307 }
308 }
309 }
310
311 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
312 if (method_entries != nullptr) {
313 for (int i = 0; i < method_entries->length(); i++) {
314 ResolvedMethodEntry* rme = method_entries->adr_at(i);
315 if (rme->is_resolved(Bytecodes::_invokehandle) && rme->has_appendix() &&
316 cache()->can_archive_resolved_method(this, rme)) {
317 int rr_index = rme->resolved_references_index();
318 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
319 function(rr_index);
320 }
321 }
322 }
323 }
324 }
325
326 // Returns the _resolved_reference array after removing unarchivable items from it.
327 // Returns null if this class is not supported, or _resolved_reference doesn't exist.
328 objArrayOop ConstantPool::prepare_resolved_references_for_archiving() {
329 if (_cache == nullptr) {
330 return nullptr; // nothing to do
331 }
332
333 InstanceKlass *ik = pool_holder();
334 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
335 // Archiving resolved references for classes from non-builtin loaders
336 // is not yet supported.
337 return nullptr;
338 }
339
340 objArrayOop rr = resolved_references();
341 if (rr != nullptr) {
342 ResourceMark rm;
343 int rr_len = rr->length();
344 GrowableArray<bool> keep_resolved_refs(rr_len, rr_len, false);
345
346 iterate_archivable_resolved_references([&](int rr_index) {
347 keep_resolved_refs.at_put(rr_index, true);
348 });
349
350 objArrayOop scratch_rr = HeapShared::scratch_resolved_references(this);
351 Array<u2>* ref_map = reference_map();
352 int ref_map_len = ref_map == nullptr ? 0 : ref_map->length();
353 for (int i = 0; i < rr_len; i++) {
354 oop obj = rr->obj_at(i);
355 scratch_rr->obj_at_put(i, nullptr);
356 if (obj != nullptr) {
357 if (i < ref_map_len) {
358 int index = object_to_cp_index(i);
359 if (tag_at(index).is_string()) {
360 assert(java_lang_String::is_instance(obj), "must be");
361 if (!ArchiveHeapWriter::is_string_too_large_to_archive(obj)) {
362 scratch_rr->obj_at_put(i, obj);
363 }
364 continue;
365 }
366 }
367
368 if (keep_resolved_refs.at(i)) {
369 scratch_rr->obj_at_put(i, obj);
370 }
371 }
372 }
373 return scratch_rr;
374 }
375 return rr;
376 }
377
378 void ConstantPool::add_dumped_interned_strings() {
379 InstanceKlass* ik = pool_holder();
380 if (!ik->is_linked()) {
381 // resolved_references() doesn't exist yet, so we have no resolved CONSTANT_String entries. However,
382 // some static final fields may have default values that were initialized when the class was parsed.
383 // We need to enter those into the CDS archive strings table.
384 for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
385 if (fs.access_flags().is_static()) {
386 fieldDescriptor& fd = fs.field_descriptor();
387 if (fd.field_type() == T_OBJECT) {
388 int offset = fd.offset();
389 check_and_add_dumped_interned_string(ik->java_mirror()->obj_field(offset));
390 }
391 }
392 }
393 } else {
394 objArrayOop rr = resolved_references();
395 if (rr != nullptr) {
396 int rr_len = rr->length();
397 for (int i = 0; i < rr_len; i++) {
398 check_and_add_dumped_interned_string(rr->obj_at(i));
399 }
400 }
401 }
402 }
403
404 void ConstantPool::check_and_add_dumped_interned_string(oop obj) {
405 if (obj != nullptr && java_lang_String::is_instance(obj) &&
406 !ArchiveHeapWriter::is_string_too_large_to_archive(obj)) {
407 HeapShared::add_to_dumped_interned_strings(obj);
408 }
409 }
410
411 #endif
412
413 #if INCLUDE_CDS
414 // CDS support. Create a new resolved_references array.
415 void ConstantPool::restore_unshareable_info(TRAPS) {
416 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
417 return;
418 }
419 assert(is_constantPool(), "ensure C++ vtable is restored");
420 assert(on_stack(), "should always be set for shared constant pools");
421 assert(is_shared(), "should always be set for shared constant pools");
422 if (is_for_method_handle_intrinsic()) {
423 // See the same check in remove_unshareable_info() below.
424 assert(cache() == nullptr, "must not have cpCache");
425 return;
426 }
427 assert(_cache != nullptr, "constant pool _cache should not be null");
428
429 // Only create the new resolved references array if it hasn't been attempted before
430 if (resolved_references() != nullptr) return;
431
432 if (vmClasses::Object_klass_loaded()) {
433 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
434 #if INCLUDE_CDS_JAVA_HEAP
435 if (ArchiveHeapLoader::is_in_use() &&
436 _cache->archived_references() != nullptr) {
437 oop archived = _cache->archived_references();
438 // Create handle for the archived resolved reference array object
439 HandleMark hm(THREAD);
440 Handle refs_handle(THREAD, archived);
441 set_resolved_references(loader_data->add_handle(refs_handle));
442 _cache->clear_archived_references();
443 } else
444 #endif
445 {
446 // No mapped archived resolved reference array
447 // Recreate the object array and add to ClassLoaderData.
448 int map_length = resolved_reference_length();
449 if (map_length > 0) {
450 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
451 HandleMark hm(THREAD);
452 Handle refs_handle(THREAD, stom); // must handleize.
453 set_resolved_references(loader_data->add_handle(refs_handle));
454 }
455 }
456 }
457
458 if (CDSConfig::is_dumping_final_static_archive() && CDSConfig::is_dumping_heap() && resolved_references() != nullptr) {
459 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), resolved_references()->length(), CHECK);
460 HeapShared::add_scratch_resolved_references(this, scratch_references);
461 }
462 }
463
464 void ConstantPool::remove_unshareable_info() {
465 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
466 // The _on_stack flag is used to prevent ConstantPools from deallocation during
467 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
468 // we always set _on_stack to true to avoid having to change _flags during runtime.
469 _flags |= (_on_stack | _is_shared);
470
471 if (is_for_method_handle_intrinsic()) {
472 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
473 // that need to be removed/restored. It has no cpCache since the intrinsic methods
474 // don't have any bytecodes.
475 assert(cache() == nullptr, "must not have cpCache");
476 return;
477 }
478
479 bool update_resolved_reference = true;
480 if (CDSConfig::is_dumping_final_static_archive()) {
481 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
482 InstanceKlass* src_holder = src_cp->pool_holder();
483 if (src_holder->is_shared_unregistered_class()) {
484 // Unregistered classes are not loaded in the AOT assembly phase. The resolved reference length
485 // is already saved during the training run.
486 precond(!src_holder->is_loaded());
487 precond(resolved_reference_length() >= 0);
488 precond(resolved_references() == nullptr);
489 update_resolved_reference = false;
490 }
491 }
492
493 // resolved_references(): remember its length. If it cannot be restored
494 // from the archived heap objects at run time, we need to dynamically allocate it.
495 if (update_resolved_reference && cache() != nullptr) {
496 set_resolved_reference_length(
497 resolved_references() != nullptr ? resolved_references()->length() : 0);
498 set_resolved_references(OopHandle());
499 }
500 remove_unshareable_entries();
501 }
502
503 static const char* get_type(Klass* k) {
504 const char* type;
505 Klass* src_k;
506 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
507 src_k = ArchiveBuilder::current()->get_source_addr(k);
508 } else {
509 src_k = k;
510 }
511
512 if (src_k->is_objArray_klass()) {
513 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
514 assert(!src_k->is_objArray_klass(), "sanity");
515 }
516
517 if (src_k->is_typeArray_klass()) {
518 type = "prim";
519 } else {
520 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
521 oop loader = src_ik->class_loader();
522 if (loader == nullptr) {
523 type = "boot";
524 } else if (loader == SystemDictionary::java_platform_loader()) {
525 type = "plat";
526 } else if (loader == SystemDictionary::java_system_loader()) {
527 type = "app";
528 } else {
529 type = "unreg";
530 }
531 }
532
533 return type;
534 }
535
536 void ConstantPool::remove_unshareable_entries() {
537 ResourceMark rm;
538 log_info(cds, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
539 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
540 int cp_tag = tag_at(cp_index).value();
541 switch (cp_tag) {
542 case JVM_CONSTANT_UnresolvedClass:
543 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, false);
544 break;
545 case JVM_CONSTANT_UnresolvedClassInError:
546 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
547 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, true);
548 break;
549 case JVM_CONSTANT_MethodHandleInError:
550 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
551 break;
552 case JVM_CONSTANT_MethodTypeInError:
553 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
554 break;
555 case JVM_CONSTANT_DynamicInError:
556 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
557 break;
558 case JVM_CONSTANT_Class:
559 remove_resolved_klass_if_non_deterministic(cp_index);
560 break;
561 default:
562 break;
563 }
564 }
565
566 if (cache() != nullptr) {
567 // cache() is null if this class is not yet linked.
568 cache()->remove_unshareable_info();
569 }
570 }
571
572 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
573 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
574 assert(tag_at(cp_index).is_klass(), "must be resolved");
575
576 Klass* k = resolved_klass_at(cp_index);
577 bool can_archive;
578
579 if (k == nullptr) {
580 // We'd come here if the referenced class has been excluded via
581 // SystemDictionaryShared::is_excluded_class(). As a result, ArchiveBuilder
582 // has cleared the resolved_klasses()->at(...) pointer to null. Thus, we
583 // need to revert the tag to JVM_CONSTANT_UnresolvedClass.
584 can_archive = false;
585 } else {
586 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
587 can_archive = AOTConstantPoolResolver::is_resolution_deterministic(src_cp, cp_index);
588 }
589
590 if (!can_archive) {
591 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
592 resolved_klasses()->at_put(resolved_klass_index, nullptr);
593 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
594 }
595
596 LogStreamHandle(Trace, cds, resolve) log;
597 if (log.is_enabled()) {
598 ResourceMark rm;
599 log.print("%s klass CP entry [%3d]: %s %s",
600 (can_archive ? "archived" : "reverted"),
601 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
602 if (can_archive) {
603 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
604 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
605 } else {
606 Symbol* name = klass_name_at(cp_index);
607 log.print(" => %s", name->as_C_string());
608 }
609 }
610
611 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(can_archive, /*reverted=*/!can_archive);
612 }
613 #endif // INCLUDE_CDS
614
615 int ConstantPool::cp_to_object_index(int cp_index) {
616 // this is harder don't do this so much.
617 int i = reference_map()->find(checked_cast<u2>(cp_index));
618 // We might not find the index for jsr292 call.
619 return (i < 0) ? _no_index_sentinel : i;
620 }
621
622 void ConstantPool::string_at_put(int obj_index, oop str) {
623 oop result = set_resolved_reference_at(obj_index, str);
624 assert(result == nullptr || result == str, "Only set once or to the same string.");
625 }
626
627 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
628 ResourceMark rm;
629 int line_number = -1;
630 const char * source_file = nullptr;
631 if (JavaThread::current()->has_last_Java_frame()) {
632 // try to identify the method which called this function.
633 vframeStream vfst(JavaThread::current());
634 if (!vfst.at_end()) {
635 line_number = vfst.method()->line_number_from_bci(vfst.bci());
636 Symbol* s = vfst.method()->method_holder()->source_file_name();
637 if (s != nullptr) {
638 source_file = s->as_C_string();
639 }
640 }
641 }
642 if (k != this_cp->pool_holder()) {
643 // only print something if the classes are different
644 if (source_file != nullptr) {
645 log_debug(class, resolve)("%s %s %s:%d",
646 this_cp->pool_holder()->external_name(),
647 k->external_name(), source_file, line_number);
648 } else {
649 log_debug(class, resolve)("%s %s",
650 this_cp->pool_holder()->external_name(),
651 k->external_name());
652 }
653 }
654 }
655
656 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
657 TRAPS) {
658 JavaThread* javaThread = THREAD;
659
660 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
661 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
662 // the entry and tag is not updated atomically.
663 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
664 int resolved_klass_index = kslot.resolved_klass_index();
665 int name_index = kslot.name_index();
666 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
667
668 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
669 // the unresolved_klasses() array.
670 if (this_cp->tag_at(cp_index).is_klass()) {
671 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
672 if (klass != nullptr) {
673 return klass;
674 }
675 }
676
677 // This tag doesn't change back to unresolved class unless at a safepoint.
678 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
679 // The original attempt to resolve this constant pool entry failed so find the
680 // class of the original error and throw another error of the same class
681 // (JVMS 5.4.3).
682 // If there is a detail message, pass that detail message to the error.
683 // The JVMS does not strictly require us to duplicate the same detail message,
684 // or any internal exception fields such as cause or stacktrace. But since the
685 // detail message is often a class name or other literal string, we will repeat it
686 // if we can find it in the symbol table.
687 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
688 ShouldNotReachHere();
689 }
690
691 HandleMark hm(THREAD);
692 Handle mirror_handle;
693 Symbol* name = this_cp->symbol_at(name_index);
694 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
695
696 Klass* k;
697 {
698 // Turn off the single stepping while doing class resolution
699 JvmtiHideSingleStepping jhss(javaThread);
700 k = SystemDictionary::resolve_or_fail(name, loader, true, THREAD);
701 } // JvmtiHideSingleStepping jhss(javaThread);
702
703 if (!HAS_PENDING_EXCEPTION) {
704 // preserve the resolved klass from unloading
705 mirror_handle = Handle(THREAD, k->java_mirror());
706 // Do access check for klasses
707 verify_constant_pool_resolve(this_cp, k, THREAD);
708 }
709
710 // Failed to resolve class. We must record the errors so that subsequent attempts
711 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
712 if (HAS_PENDING_EXCEPTION) {
713 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
714 // If CHECK_NULL above doesn't return the exception, that means that
715 // some other thread has beaten us and has resolved the class.
716 // To preserve old behavior, we return the resolved class.
717 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
718 assert(klass != nullptr, "must be resolved if exception was cleared");
719 return klass;
720 }
721
722 // logging for class+resolve.
723 if (log_is_enabled(Debug, class, resolve)){
724 trace_class_resolution(this_cp, k);
725 }
726
727 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
728 Atomic::release_store(adr, k);
729 // The interpreter assumes when the tag is stored, the klass is resolved
730 // and the Klass* stored in _resolved_klasses is non-null, so we need
731 // hardware store ordering here.
732 // We also need to CAS to not overwrite an error from a racing thread.
733
734 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
735 (jbyte)JVM_CONSTANT_UnresolvedClass,
736 (jbyte)JVM_CONSTANT_Class);
737
738 // We need to recheck exceptions from racing thread and return the same.
739 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
740 // Remove klass.
741 this_cp->resolved_klasses()->at_put(resolved_klass_index, nullptr);
742 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
743 }
744
745 return k;
746 }
747
748
749 // Does not update ConstantPool* - to avoid any exception throwing. Used
750 // by compiler and exception handling. Also used to avoid classloads for
751 // instanceof operations. Returns null if the class has not been loaded or
752 // if the verification of constant pool failed
753 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
754 CPKlassSlot kslot = this_cp->klass_slot_at(which);
755 int resolved_klass_index = kslot.resolved_klass_index();
756 int name_index = kslot.name_index();
757 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
758
759 if (this_cp->tag_at(which).is_klass()) {
760 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
761 assert(k != nullptr, "should be resolved");
762 return k;
763 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
764 return nullptr;
765 } else {
766 Thread* current = Thread::current();
767 HandleMark hm(current);
768 Symbol* name = this_cp->symbol_at(name_index);
769 oop loader = this_cp->pool_holder()->class_loader();
770 Handle h_loader (current, loader);
771 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader);
772
773 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
774 if (k != nullptr && current->is_Java_thread()) {
775 // Make sure that resolving is legal
776 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
777 ExceptionMark em(THREAD);
778 // return null if verification fails
779 verify_constant_pool_resolve(this_cp, k, THREAD);
780 if (HAS_PENDING_EXCEPTION) {
781 CLEAR_PENDING_EXCEPTION;
782 return nullptr;
783 }
784 return k;
785 } else {
786 return k;
787 }
788 }
789 }
790
791 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
792 int which) {
793 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
794 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
795 // FIXME: should be an assert
796 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
797 return nullptr;
798 }
799 return cpool->cache()->method_if_resolved(which);
800 }
801
802
803 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
804 if (cpool->cache() == nullptr) return false; // nothing to load yet
805 if (code == Bytecodes::_invokedynamic) {
806 return cpool->resolved_indy_entry_at(which)->has_appendix();
807 } else {
808 return cpool->resolved_method_entry_at(which)->has_appendix();
809 }
810 }
811
812 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
813 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
814 if (code == Bytecodes::_invokedynamic) {
815 return cpool->resolved_reference_from_indy(which);
816 } else {
817 return cpool->cache()->appendix_if_resolved(which);
818 }
819 }
820
821
822 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
823 if (cpool->cache() == nullptr) return false; // nothing to load yet
824 if (code == Bytecodes::_invokedynamic) {
825 return cpool->resolved_indy_entry_at(which)->has_local_signature();
826 } else {
827 return cpool->resolved_method_entry_at(which)->has_local_signature();
828 }
829 }
830
831 // Translate index, which could be CPCache index or Indy index, to a constant pool index
832 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
833 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
834 switch(code) {
835 case Bytecodes::_invokedynamic:
836 return invokedynamic_bootstrap_ref_index_at(index);
837 case Bytecodes::_getfield:
838 case Bytecodes::_getstatic:
839 case Bytecodes::_putfield:
840 case Bytecodes::_putstatic:
841 return resolved_field_entry_at(index)->constant_pool_index();
842 case Bytecodes::_invokeinterface:
843 case Bytecodes::_invokehandle:
844 case Bytecodes::_invokespecial:
845 case Bytecodes::_invokestatic:
846 case Bytecodes::_invokevirtual:
847 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
848 return resolved_method_entry_at(index)->constant_pool_index();
849 default:
850 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
851 }
852 }
853
854 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
855 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
856 switch(code) {
857 case Bytecodes::_invokedynamic:
858 return resolved_indy_entry_at(index)->is_resolved();
859
860 case Bytecodes::_getfield:
861 case Bytecodes::_getstatic:
862 case Bytecodes::_putfield:
863 case Bytecodes::_putstatic:
864 return resolved_field_entry_at(index)->is_resolved(code);
865
866 case Bytecodes::_invokeinterface:
867 case Bytecodes::_invokehandle:
868 case Bytecodes::_invokespecial:
869 case Bytecodes::_invokestatic:
870 case Bytecodes::_invokevirtual:
871 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
872 return resolved_method_entry_at(index)->is_resolved(code);
873
874 default:
875 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
876 }
877 }
878
879 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
880 if (tag_at(cp_index).has_bootstrap()) {
881 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
882 assert(tag_at(pool_index).is_name_and_type(), "");
883 return pool_index;
884 }
885 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
886 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
887 jint ref_index = *int_at_addr(cp_index);
888 return extract_high_short_from_int(ref_index);
889 }
890
891 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
892 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
893 }
894
895 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
896 // which may be either a Constant Pool index or a rewritten index
897 int pool_index = which;
898 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
899 pool_index = to_cp_index(which, code);
900 return tag_at(pool_index);
901 }
902
903 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
904 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
905 jint ref_index = *int_at_addr(cp_index);
906 return extract_low_short_from_int(ref_index);
907 }
908
909 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
910 assert(code != Bytecodes::_invokedynamic,
911 "an invokedynamic instruction does not have a klass");
912 return uncached_klass_ref_index_at(to_cp_index(index, code));
913 }
914
915 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
916 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
917 return; // short cut, typeArray klass is always accessible
918 }
919 Klass* holder = this_cp->pool_holder();
920 LinkResolver::check_klass_accessibility(holder, k, CHECK);
921 }
922
923
924 u2 ConstantPool::name_ref_index_at(int cp_index) {
925 jint ref_index = name_and_type_at(cp_index);
926 return extract_low_short_from_int(ref_index);
927 }
928
929
930 u2 ConstantPool::signature_ref_index_at(int cp_index) {
931 jint ref_index = name_and_type_at(cp_index);
932 return extract_high_short_from_int(ref_index);
933 }
934
935
936 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
937 return klass_at(klass_ref_index_at(which, code), THREAD);
938 }
939
940 Symbol* ConstantPool::klass_name_at(int cp_index) const {
941 return symbol_at(klass_slot_at(cp_index).name_index());
942 }
943
944 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
945 jint ref_index = klass_ref_index_at(which, code);
946 return klass_at_noresolve(ref_index);
947 }
948
949 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
950 jint ref_index = uncached_klass_ref_index_at(cp_index);
951 return klass_at_noresolve(ref_index);
952 }
953
954 char* ConstantPool::string_at_noresolve(int cp_index) {
955 return unresolved_string_at(cp_index)->as_C_string();
956 }
957
958 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
959 return Signature::basic_type(symbol_at(cp_index));
960 }
961
962
963 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
964 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
965 if (this_cp->tag_at(index).is_string()) {
966 this_cp->string_at(index, CHECK);
967 }
968 }
969 }
970
971 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
972 // Note: caller needs ResourceMark
973
974 // Dig out the detailed message to reuse if possible
975 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
976 if (msg != nullptr) {
977 return msg;
978 }
979
980 Symbol* message = nullptr;
981 // Return specific message for the tag
982 switch (tag.value()) {
983 case JVM_CONSTANT_UnresolvedClass:
984 // return the class name in the error message
985 message = this_cp->klass_name_at(which);
986 break;
987 case JVM_CONSTANT_MethodHandle:
988 // return the method handle name in the error message
989 message = this_cp->method_handle_name_ref_at(which);
990 break;
991 case JVM_CONSTANT_MethodType:
992 // return the method type signature in the error message
993 message = this_cp->method_type_signature_at(which);
994 break;
995 case JVM_CONSTANT_Dynamic:
996 // return the name of the condy in the error message
997 message = this_cp->uncached_name_ref_at(which);
998 break;
999 default:
1000 ShouldNotReachHere();
1001 }
1002
1003 return message != nullptr ? message->as_C_string() : nullptr;
1004 }
1005
1006 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
1007 constantTag tag, oop pending_exception) {
1008
1009 ResourceMark rm(current);
1010 Symbol* error = pending_exception->klass()->name();
1011 oop cause = java_lang_Throwable::cause(pending_exception);
1012
1013 // Also dig out the exception cause, if present.
1014 Symbol* cause_sym = nullptr;
1015 const char* cause_msg = nullptr;
1016 if (cause != nullptr && cause != pending_exception) {
1017 cause_sym = cause->klass()->name();
1018 cause_msg = java_lang_Throwable::message_as_utf8(cause);
1019 }
1020
1021 const char* message = exception_message(this_cp, which, tag, pending_exception);
1022 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1023 }
1024
1025
1026 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1027 ResourceMark rm(THREAD);
1028 const char* message = nullptr;
1029 Symbol* cause = nullptr;
1030 const char* cause_msg = nullptr;
1031 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1032 assert(error != nullptr, "checking");
1033
1034 CLEAR_PENDING_EXCEPTION;
1035 if (message != nullptr) {
1036 if (cause != nullptr) {
1037 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1038 THROW_MSG_CAUSE(error, message, h_cause);
1039 } else {
1040 THROW_MSG(error, message);
1041 }
1042 } else {
1043 if (cause != nullptr) {
1044 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1045 THROW_CAUSE(error, h_cause);
1046 } else {
1047 THROW(error);
1048 }
1049 }
1050 }
1051
1052 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1053 // exception in the resolution error table, so that the same exception is thrown again.
1054 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1055 constantTag tag, TRAPS) {
1056
1057 int error_tag = tag.error_value();
1058
1059 if (!PENDING_EXCEPTION->
1060 is_a(vmClasses::LinkageError_klass())) {
1061 // Just throw the exception and don't prevent these classes from
1062 // being loaded due to virtual machine errors like StackOverflow
1063 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1064 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1065 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1066 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1067 // CAS in the tag. If a thread beat us to registering this error that's fine.
1068 // If another thread resolved the reference, this is a race condition. This
1069 // thread may have had a security manager or something temporary.
1070 // This doesn't deterministically get an error. So why do we save this?
1071 // We save this because jvmti can add classes to the bootclass path after
1072 // this error, so it needs to get the same error if the error is first.
1073 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1074 (jbyte)tag.value(),
1075 (jbyte)error_tag);
1076 if (old_tag != error_tag && old_tag != tag.value()) {
1077 // MethodHandles and MethodType doesn't change to resolved version.
1078 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1079 // Forget the exception and use the resolved class.
1080 CLEAR_PENDING_EXCEPTION;
1081 }
1082 } else {
1083 // some other thread put this in error state
1084 throw_resolution_error(this_cp, cp_index, CHECK);
1085 }
1086 }
1087
1088 constantTag ConstantPool::constant_tag_at(int cp_index) {
1089 constantTag tag = tag_at(cp_index);
1090 if (tag.is_dynamic_constant()) {
1091 BasicType bt = basic_type_for_constant_at(cp_index);
1092 return constantTag(constantTag::type2tag(bt));
1093 }
1094 return tag;
1095 }
1096
1097 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1098 constantTag tag = tag_at(cp_index);
1099 if (tag.is_dynamic_constant() ||
1100 tag.is_dynamic_constant_in_error()) {
1101 // have to look at the signature for this one
1102 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1103 return Signature::basic_type(constant_type);
1104 }
1105 return tag.basic_type();
1106 }
1107
1108 // Called to resolve constants in the constant pool and return an oop.
1109 // Some constant pool entries cache their resolved oop. This is also
1110 // called to create oops from constants to use in arguments for invokedynamic
1111 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1112 int cp_index, int cache_index,
1113 bool* status_return, TRAPS) {
1114 oop result_oop = nullptr;
1115
1116 if (cache_index == _possible_index_sentinel) {
1117 // It is possible that this constant is one which is cached in the objects.
1118 // We'll do a linear search. This should be OK because this usage is rare.
1119 // FIXME: If bootstrap specifiers stress this code, consider putting in
1120 // a reverse index. Binary search over a short array should do it.
1121 assert(cp_index > 0, "valid constant pool index");
1122 cache_index = this_cp->cp_to_object_index(cp_index);
1123 }
1124 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1125 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1126
1127 if (cache_index >= 0) {
1128 result_oop = this_cp->resolved_reference_at(cache_index);
1129 if (result_oop != nullptr) {
1130 if (result_oop == Universe::the_null_sentinel()) {
1131 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1132 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1133 result_oop = nullptr;
1134 }
1135 if (status_return != nullptr) (*status_return) = true;
1136 return result_oop;
1137 // That was easy...
1138 }
1139 cp_index = this_cp->object_to_cp_index(cache_index);
1140 }
1141
1142 jvalue prim_value; // temp used only in a few cases below
1143
1144 constantTag tag = this_cp->tag_at(cp_index);
1145
1146 if (status_return != nullptr) {
1147 // don't trigger resolution if the constant might need it
1148 switch (tag.value()) {
1149 case JVM_CONSTANT_Class:
1150 {
1151 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
1152 int resolved_klass_index = kslot.resolved_klass_index();
1153 if (this_cp->resolved_klasses()->at(resolved_klass_index) == nullptr) {
1154 (*status_return) = false;
1155 return nullptr;
1156 }
1157 // the klass is waiting in the CP; go get it
1158 break;
1159 }
1160 case JVM_CONSTANT_String:
1161 case JVM_CONSTANT_Integer:
1162 case JVM_CONSTANT_Float:
1163 case JVM_CONSTANT_Long:
1164 case JVM_CONSTANT_Double:
1165 // these guys trigger OOM at worst
1166 break;
1167 default:
1168 (*status_return) = false;
1169 return nullptr;
1170 }
1171 // from now on there is either success or an OOME
1172 (*status_return) = true;
1173 }
1174
1175 switch (tag.value()) {
1176
1177 case JVM_CONSTANT_UnresolvedClass:
1178 case JVM_CONSTANT_Class:
1179 {
1180 assert(cache_index == _no_index_sentinel, "should not have been set");
1181 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1182 // ldc wants the java mirror.
1183 result_oop = resolved->java_mirror();
1184 break;
1185 }
1186
1187 case JVM_CONSTANT_Dynamic:
1188 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1189 ClassLoader::perf_resolve_invokedynamic_count());
1190
1191 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1192 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1193
1194 // The initial step in resolving an unresolved symbolic reference to a
1195 // dynamically-computed constant is to resolve the symbolic reference to a
1196 // method handle which will be the bootstrap method for the dynamically-computed
1197 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1198 // method fails, then a MethodHandleInError is stored at the corresponding
1199 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1200 // set a DynamicConstantInError here since any subsequent use of this
1201 // bootstrap method will encounter the resolution of MethodHandleInError.
1202 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1203 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1204 // for the bootstrap_specifier created above.
1205 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1206 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1207 if (HAS_PENDING_EXCEPTION) {
1208 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1209 // will check for a LinkageError and store a DynamicConstantInError.
1210 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1211 }
1212 result_oop = bootstrap_specifier.resolved_value()();
1213 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1214 if (!is_reference_type(type)) {
1215 // Make sure the primitive value is properly boxed.
1216 // This is a JDK responsibility.
1217 const char* fail = nullptr;
1218 if (result_oop == nullptr) {
1219 fail = "null result instead of box";
1220 } else if (!is_java_primitive(type)) {
1221 // FIXME: support value types via unboxing
1222 fail = "can only handle references and primitives";
1223 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1224 fail = "primitive is not properly boxed";
1225 }
1226 if (fail != nullptr) {
1227 // Since this exception is not a LinkageError, throw exception
1228 // but do not save a DynamicInError resolution result.
1229 // See section 5.4.3 of the VM spec.
1230 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1231 }
1232 }
1233
1234 LogTarget(Debug, methodhandles, condy) lt_condy;
1235 if (lt_condy.is_enabled()) {
1236 LogStream ls(lt_condy);
1237 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1238 }
1239 break;
1240 }
1241
1242 case JVM_CONSTANT_String:
1243 assert(cache_index != _no_index_sentinel, "should have been set");
1244 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1245 break;
1246
1247 case JVM_CONSTANT_MethodHandle:
1248 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1249 ClassLoader::perf_resolve_method_handle_count());
1250
1251 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1252 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1253 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1254 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1255 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1256 { ResourceMark rm(THREAD);
1257 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1258 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1259 callee_index, name->as_C_string(), signature->as_C_string());
1260 }
1261
1262 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1263 if (HAS_PENDING_EXCEPTION) {
1264 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1265 }
1266
1267 // Check constant pool method consistency
1268 if ((callee->is_interface() && m_tag.is_method()) ||
1269 (!callee->is_interface() && m_tag.is_interface_method())) {
1270 ResourceMark rm(THREAD);
1271 stringStream ss;
1272 ss.print("Inconsistent constant pool data in classfile for class %s. "
1273 "Method '", callee->name()->as_C_string());
1274 signature->print_as_signature_external_return_type(&ss);
1275 ss.print(" %s(", name->as_C_string());
1276 signature->print_as_signature_external_parameters(&ss);
1277 ss.print(")' at index %d is %s and should be %s",
1278 cp_index,
1279 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1280 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1281 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1282 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1283 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1284 }
1285
1286 Klass* klass = this_cp->pool_holder();
1287 HandleMark hm(THREAD);
1288 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1289 callee, name, signature,
1290 THREAD);
1291 if (HAS_PENDING_EXCEPTION) {
1292 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1293 }
1294 result_oop = value();
1295 break;
1296 }
1297
1298 case JVM_CONSTANT_MethodType:
1299 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1300 ClassLoader::perf_resolve_method_type_count());
1301
1302 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1303 { ResourceMark rm(THREAD);
1304 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1305 cp_index, this_cp->method_type_index_at(cp_index),
1306 signature->as_C_string());
1307 }
1308 Klass* klass = this_cp->pool_holder();
1309 HandleMark hm(THREAD);
1310 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1311 result_oop = value();
1312 if (HAS_PENDING_EXCEPTION) {
1313 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1314 }
1315 break;
1316 }
1317
1318 case JVM_CONSTANT_Integer:
1319 assert(cache_index == _no_index_sentinel, "should not have been set");
1320 prim_value.i = this_cp->int_at(cp_index);
1321 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1322 break;
1323
1324 case JVM_CONSTANT_Float:
1325 assert(cache_index == _no_index_sentinel, "should not have been set");
1326 prim_value.f = this_cp->float_at(cp_index);
1327 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1328 break;
1329
1330 case JVM_CONSTANT_Long:
1331 assert(cache_index == _no_index_sentinel, "should not have been set");
1332 prim_value.j = this_cp->long_at(cp_index);
1333 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1334 break;
1335
1336 case JVM_CONSTANT_Double:
1337 assert(cache_index == _no_index_sentinel, "should not have been set");
1338 prim_value.d = this_cp->double_at(cp_index);
1339 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1340 break;
1341
1342 case JVM_CONSTANT_UnresolvedClassInError:
1343 case JVM_CONSTANT_DynamicInError:
1344 case JVM_CONSTANT_MethodHandleInError:
1345 case JVM_CONSTANT_MethodTypeInError:
1346 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1347 break;
1348
1349 default:
1350 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1351 break;
1352 }
1353
1354 if (cache_index >= 0) {
1355 // Benign race condition: resolved_references may already be filled in.
1356 // The important thing here is that all threads pick up the same result.
1357 // It doesn't matter which racing thread wins, as long as only one
1358 // result is used by all threads, and all future queries.
1359 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1360 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1361 if (old_result == nullptr) {
1362 return result_oop; // was installed
1363 } else {
1364 // Return the winning thread's result. This can be different than
1365 // the result here for MethodHandles.
1366 if (old_result == Universe::the_null_sentinel())
1367 old_result = nullptr;
1368 return old_result;
1369 }
1370 } else {
1371 assert(result_oop != Universe::the_null_sentinel(), "");
1372 return result_oop;
1373 }
1374 }
1375
1376 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1377 Symbol* sym = unresolved_string_at(cp_index);
1378 oop str = StringTable::intern(sym, CHECK_(nullptr));
1379 assert(java_lang_String::is_instance(str), "must be string");
1380 return str;
1381 }
1382
1383 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1384 int start_arg, int end_arg,
1385 objArrayHandle info, int pos,
1386 bool must_resolve, Handle if_not_available,
1387 TRAPS) {
1388 int limit = pos + end_arg - start_arg;
1389 // checks: cp_index in range [0..this_cp->length),
1390 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1391 // info array non-null, pos..limit in [0..info.length]
1392 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1393 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1394 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1395 (0 > start_arg || start_arg > end_arg) ||
1396 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1397 (0 > pos || pos > limit) ||
1398 (info.is_null() || limit > info->length())) {
1399 // An index or something else went wrong; throw an error.
1400 // Since this is an internal API, we don't expect this,
1401 // so we don't bother to craft a nice message.
1402 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1403 }
1404 // now we can loop safely
1405 int info_i = pos;
1406 for (int i = start_arg; i < end_arg; i++) {
1407 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1408 oop arg_oop;
1409 if (must_resolve) {
1410 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1411 } else {
1412 bool found_it = false;
1413 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1414 if (!found_it) arg_oop = if_not_available();
1415 }
1416 info->obj_at_put(info_i++, arg_oop);
1417 }
1418 }
1419
1420 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1421 // If the string has already been interned, this entry will be non-null
1422 oop str = this_cp->resolved_reference_at(obj_index);
1423 assert(str != Universe::the_null_sentinel(), "");
1424 if (str != nullptr) return str;
1425 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1426 str = StringTable::intern(sym, CHECK_(nullptr));
1427 this_cp->string_at_put(obj_index, str);
1428 assert(java_lang_String::is_instance(str), "must be string");
1429 return str;
1430 }
1431
1432
1433 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1434 // Names are interned, so we can compare Symbol*s directly
1435 Symbol* cp_name = klass_name_at(cp_index);
1436 return (cp_name == k->name());
1437 }
1438
1439
1440 // Iterate over symbols and decrement ones which are Symbol*s
1441 // This is done during GC.
1442 // Only decrement the UTF8 symbols. Strings point to
1443 // these symbols but didn't increment the reference count.
1444 void ConstantPool::unreference_symbols() {
1445 for (int index = 1; index < length(); index++) { // Index 0 is unused
1446 constantTag tag = tag_at(index);
1447 if (tag.is_symbol()) {
1448 symbol_at(index)->decrement_refcount();
1449 }
1450 }
1451 }
1452
1453
1454 // Compare this constant pool's entry at index1 to the constant pool
1455 // cp2's entry at index2.
1456 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1457 int index2) {
1458
1459 // The error tags are equivalent to non-error tags when comparing
1460 jbyte t1 = tag_at(index1).non_error_value();
1461 jbyte t2 = cp2->tag_at(index2).non_error_value();
1462
1463 // Some classes are pre-resolved (like Throwable) which may lead to
1464 // consider it as a different entry. We then revert them back temporarily
1465 // to ensure proper comparison.
1466 if (t1 == JVM_CONSTANT_Class) {
1467 t1 = JVM_CONSTANT_UnresolvedClass;
1468 }
1469 if (t2 == JVM_CONSTANT_Class) {
1470 t2 = JVM_CONSTANT_UnresolvedClass;
1471 }
1472
1473 if (t1 != t2) {
1474 // Not the same entry type so there is nothing else to check. Note
1475 // that this style of checking will consider resolved/unresolved
1476 // class pairs as different.
1477 // From the ConstantPool* API point of view, this is correct
1478 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1479 // plays out in the context of ConstantPool* merging.
1480 return false;
1481 }
1482
1483 switch (t1) {
1484 case JVM_CONSTANT_ClassIndex:
1485 {
1486 int recur1 = klass_index_at(index1);
1487 int recur2 = cp2->klass_index_at(index2);
1488 if (compare_entry_to(recur1, cp2, recur2)) {
1489 return true;
1490 }
1491 } break;
1492
1493 case JVM_CONSTANT_Double:
1494 {
1495 jdouble d1 = double_at(index1);
1496 jdouble d2 = cp2->double_at(index2);
1497 if (d1 == d2) {
1498 return true;
1499 }
1500 } break;
1501
1502 case JVM_CONSTANT_Fieldref:
1503 case JVM_CONSTANT_InterfaceMethodref:
1504 case JVM_CONSTANT_Methodref:
1505 {
1506 int recur1 = uncached_klass_ref_index_at(index1);
1507 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1508 bool match = compare_entry_to(recur1, cp2, recur2);
1509 if (match) {
1510 recur1 = uncached_name_and_type_ref_index_at(index1);
1511 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1512 if (compare_entry_to(recur1, cp2, recur2)) {
1513 return true;
1514 }
1515 }
1516 } break;
1517
1518 case JVM_CONSTANT_Float:
1519 {
1520 jfloat f1 = float_at(index1);
1521 jfloat f2 = cp2->float_at(index2);
1522 if (f1 == f2) {
1523 return true;
1524 }
1525 } break;
1526
1527 case JVM_CONSTANT_Integer:
1528 {
1529 jint i1 = int_at(index1);
1530 jint i2 = cp2->int_at(index2);
1531 if (i1 == i2) {
1532 return true;
1533 }
1534 } break;
1535
1536 case JVM_CONSTANT_Long:
1537 {
1538 jlong l1 = long_at(index1);
1539 jlong l2 = cp2->long_at(index2);
1540 if (l1 == l2) {
1541 return true;
1542 }
1543 } break;
1544
1545 case JVM_CONSTANT_NameAndType:
1546 {
1547 int recur1 = name_ref_index_at(index1);
1548 int recur2 = cp2->name_ref_index_at(index2);
1549 if (compare_entry_to(recur1, cp2, recur2)) {
1550 recur1 = signature_ref_index_at(index1);
1551 recur2 = cp2->signature_ref_index_at(index2);
1552 if (compare_entry_to(recur1, cp2, recur2)) {
1553 return true;
1554 }
1555 }
1556 } break;
1557
1558 case JVM_CONSTANT_StringIndex:
1559 {
1560 int recur1 = string_index_at(index1);
1561 int recur2 = cp2->string_index_at(index2);
1562 if (compare_entry_to(recur1, cp2, recur2)) {
1563 return true;
1564 }
1565 } break;
1566
1567 case JVM_CONSTANT_UnresolvedClass:
1568 {
1569 Symbol* k1 = klass_name_at(index1);
1570 Symbol* k2 = cp2->klass_name_at(index2);
1571 if (k1 == k2) {
1572 return true;
1573 }
1574 } break;
1575
1576 case JVM_CONSTANT_MethodType:
1577 {
1578 int k1 = method_type_index_at(index1);
1579 int k2 = cp2->method_type_index_at(index2);
1580 if (compare_entry_to(k1, cp2, k2)) {
1581 return true;
1582 }
1583 } break;
1584
1585 case JVM_CONSTANT_MethodHandle:
1586 {
1587 int k1 = method_handle_ref_kind_at(index1);
1588 int k2 = cp2->method_handle_ref_kind_at(index2);
1589 if (k1 == k2) {
1590 int i1 = method_handle_index_at(index1);
1591 int i2 = cp2->method_handle_index_at(index2);
1592 if (compare_entry_to(i1, cp2, i2)) {
1593 return true;
1594 }
1595 }
1596 } break;
1597
1598 case JVM_CONSTANT_Dynamic:
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_InvokeDynamic:
1610 {
1611 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1612 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1613 int i1 = bootstrap_methods_attribute_index(index1);
1614 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1615 bool match_entry = compare_entry_to(k1, cp2, k2);
1616 bool match_operand = compare_operand_to(i1, cp2, i2);
1617 return (match_entry && match_operand);
1618 } break;
1619
1620 case JVM_CONSTANT_String:
1621 {
1622 Symbol* s1 = unresolved_string_at(index1);
1623 Symbol* s2 = cp2->unresolved_string_at(index2);
1624 if (s1 == s2) {
1625 return true;
1626 }
1627 } break;
1628
1629 case JVM_CONSTANT_Utf8:
1630 {
1631 Symbol* s1 = symbol_at(index1);
1632 Symbol* s2 = cp2->symbol_at(index2);
1633 if (s1 == s2) {
1634 return true;
1635 }
1636 } break;
1637
1638 // Invalid is used as the tag for the second constant pool entry
1639 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1640 // not be seen by itself.
1641 case JVM_CONSTANT_Invalid: // fall through
1642
1643 default:
1644 ShouldNotReachHere();
1645 break;
1646 }
1647
1648 return false;
1649 } // end compare_entry_to()
1650
1651
1652 // Resize the operands array with delta_len and delta_size.
1653 // Used in RedefineClasses for CP merge.
1654 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1655 int old_len = operand_array_length(operands());
1656 int new_len = old_len + delta_len;
1657 int min_len = (delta_len > 0) ? old_len : new_len;
1658
1659 int old_size = operands()->length();
1660 int new_size = old_size + delta_size;
1661 int min_size = (delta_size > 0) ? old_size : new_size;
1662
1663 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1664 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1665
1666 // Set index in the resized array for existing elements only
1667 for (int idx = 0; idx < min_len; idx++) {
1668 int offset = operand_offset_at(idx); // offset in original array
1669 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1670 }
1671 // Copy the bootstrap specifiers only
1672 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1673 new_ops->adr_at(2*new_len),
1674 (min_size - 2*min_len) * sizeof(u2));
1675 // Explicitly deallocate old operands array.
1676 // Note, it is not needed for 7u backport.
1677 if ( operands() != nullptr) { // the safety check
1678 MetadataFactory::free_array<u2>(loader_data, operands());
1679 }
1680 set_operands(new_ops);
1681 } // end resize_operands()
1682
1683
1684 // Extend the operands array with the length and size of the ext_cp operands.
1685 // Used in RedefineClasses for CP merge.
1686 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1687 int delta_len = operand_array_length(ext_cp->operands());
1688 if (delta_len == 0) {
1689 return; // nothing to do
1690 }
1691 int delta_size = ext_cp->operands()->length();
1692
1693 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1694
1695 if (operand_array_length(operands()) == 0) {
1696 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1697 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1698 // The first element index defines the offset of second part
1699 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1700 set_operands(new_ops);
1701 } else {
1702 resize_operands(delta_len, delta_size, CHECK);
1703 }
1704
1705 } // end extend_operands()
1706
1707
1708 // Shrink the operands array to a smaller array with new_len length.
1709 // Used in RedefineClasses for CP merge.
1710 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1711 int old_len = operand_array_length(operands());
1712 if (new_len == old_len) {
1713 return; // nothing to do
1714 }
1715 assert(new_len < old_len, "shrunken operands array must be smaller");
1716
1717 int free_base = operand_next_offset_at(new_len - 1);
1718 int delta_len = new_len - old_len;
1719 int delta_size = 2*delta_len + free_base - operands()->length();
1720
1721 resize_operands(delta_len, delta_size, CHECK);
1722
1723 } // end shrink_operands()
1724
1725
1726 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1727 const constantPoolHandle& to_cp,
1728 TRAPS) {
1729
1730 int from_oplen = operand_array_length(from_cp->operands());
1731 int old_oplen = operand_array_length(to_cp->operands());
1732 if (from_oplen != 0) {
1733 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1734 // append my operands to the target's operands array
1735 if (old_oplen == 0) {
1736 // Can't just reuse from_cp's operand list because of deallocation issues
1737 int len = from_cp->operands()->length();
1738 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1739 Copy::conjoint_memory_atomic(
1740 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1741 to_cp->set_operands(new_ops);
1742 } else {
1743 int old_len = to_cp->operands()->length();
1744 int from_len = from_cp->operands()->length();
1745 int old_off = old_oplen * sizeof(u2);
1746 int from_off = from_oplen * sizeof(u2);
1747 // Use the metaspace for the destination constant pool
1748 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1749 int fillp = 0, len = 0;
1750 // first part of dest
1751 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1752 new_operands->adr_at(fillp),
1753 (len = old_off) * sizeof(u2));
1754 fillp += len;
1755 // first part of src
1756 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1757 new_operands->adr_at(fillp),
1758 (len = from_off) * sizeof(u2));
1759 fillp += len;
1760 // second part of dest
1761 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1762 new_operands->adr_at(fillp),
1763 (len = old_len - old_off) * sizeof(u2));
1764 fillp += len;
1765 // second part of src
1766 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1767 new_operands->adr_at(fillp),
1768 (len = from_len - from_off) * sizeof(u2));
1769 fillp += len;
1770 assert(fillp == new_operands->length(), "");
1771
1772 // Adjust indexes in the first part of the copied operands array.
1773 for (int j = 0; j < from_oplen; j++) {
1774 int offset = operand_offset_at(new_operands, old_oplen + j);
1775 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1776 offset += old_len; // every new tuple is preceded by old_len extra u2's
1777 operand_offset_at_put(new_operands, old_oplen + j, offset);
1778 }
1779
1780 // replace target operands array with combined array
1781 to_cp->set_operands(new_operands);
1782 }
1783 }
1784 } // end copy_operands()
1785
1786
1787 // Copy this constant pool's entries at start_i to end_i (inclusive)
1788 // to the constant pool to_cp's entries starting at to_i. A total of
1789 // (end_i - start_i) + 1 entries are copied.
1790 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1791 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1792
1793
1794 int dest_cpi = to_i; // leave original alone for debug purposes
1795
1796 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1797 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1798
1799 switch (from_cp->tag_at(src_cpi).value()) {
1800 case JVM_CONSTANT_Double:
1801 case JVM_CONSTANT_Long:
1802 // double and long take two constant pool entries
1803 src_cpi += 2;
1804 dest_cpi += 2;
1805 break;
1806
1807 default:
1808 // all others take one constant pool entry
1809 src_cpi++;
1810 dest_cpi++;
1811 break;
1812 }
1813 }
1814 copy_operands(from_cp, to_cp, CHECK);
1815
1816 } // end copy_cp_to_impl()
1817
1818
1819 // Copy this constant pool's entry at from_i to the constant pool
1820 // to_cp's entry at to_i.
1821 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1822 const constantPoolHandle& to_cp, int to_i) {
1823
1824 int tag = from_cp->tag_at(from_i).value();
1825 switch (tag) {
1826 case JVM_CONSTANT_ClassIndex:
1827 {
1828 jint ki = from_cp->klass_index_at(from_i);
1829 to_cp->klass_index_at_put(to_i, ki);
1830 } break;
1831
1832 case JVM_CONSTANT_Double:
1833 {
1834 jdouble d = from_cp->double_at(from_i);
1835 to_cp->double_at_put(to_i, d);
1836 // double takes two constant pool entries so init second entry's tag
1837 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1838 } break;
1839
1840 case JVM_CONSTANT_Fieldref:
1841 {
1842 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1843 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1844 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1845 } break;
1846
1847 case JVM_CONSTANT_Float:
1848 {
1849 jfloat f = from_cp->float_at(from_i);
1850 to_cp->float_at_put(to_i, f);
1851 } break;
1852
1853 case JVM_CONSTANT_Integer:
1854 {
1855 jint i = from_cp->int_at(from_i);
1856 to_cp->int_at_put(to_i, i);
1857 } break;
1858
1859 case JVM_CONSTANT_InterfaceMethodref:
1860 {
1861 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1862 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1863 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1864 } break;
1865
1866 case JVM_CONSTANT_Long:
1867 {
1868 jlong l = from_cp->long_at(from_i);
1869 to_cp->long_at_put(to_i, l);
1870 // long takes two constant pool entries so init second entry's tag
1871 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1872 } break;
1873
1874 case JVM_CONSTANT_Methodref:
1875 {
1876 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1877 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1878 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1879 } break;
1880
1881 case JVM_CONSTANT_NameAndType:
1882 {
1883 int name_ref_index = from_cp->name_ref_index_at(from_i);
1884 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1885 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1886 } break;
1887
1888 case JVM_CONSTANT_StringIndex:
1889 {
1890 jint si = from_cp->string_index_at(from_i);
1891 to_cp->string_index_at_put(to_i, si);
1892 } break;
1893
1894 case JVM_CONSTANT_Class:
1895 case JVM_CONSTANT_UnresolvedClass:
1896 case JVM_CONSTANT_UnresolvedClassInError:
1897 {
1898 // Revert to JVM_CONSTANT_ClassIndex
1899 int name_index = from_cp->klass_slot_at(from_i).name_index();
1900 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1901 to_cp->klass_index_at_put(to_i, name_index);
1902 } break;
1903
1904 case JVM_CONSTANT_String:
1905 {
1906 Symbol* s = from_cp->unresolved_string_at(from_i);
1907 to_cp->unresolved_string_at_put(to_i, s);
1908 } break;
1909
1910 case JVM_CONSTANT_Utf8:
1911 {
1912 Symbol* s = from_cp->symbol_at(from_i);
1913 // Need to increase refcount, the old one will be thrown away and deferenced
1914 s->increment_refcount();
1915 to_cp->symbol_at_put(to_i, s);
1916 } break;
1917
1918 case JVM_CONSTANT_MethodType:
1919 case JVM_CONSTANT_MethodTypeInError:
1920 {
1921 jint k = from_cp->method_type_index_at(from_i);
1922 to_cp->method_type_index_at_put(to_i, k);
1923 } break;
1924
1925 case JVM_CONSTANT_MethodHandle:
1926 case JVM_CONSTANT_MethodHandleInError:
1927 {
1928 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1929 int k2 = from_cp->method_handle_index_at(from_i);
1930 to_cp->method_handle_index_at_put(to_i, k1, k2);
1931 } break;
1932
1933 case JVM_CONSTANT_Dynamic:
1934 case JVM_CONSTANT_DynamicInError:
1935 {
1936 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1937 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1938 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1939 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1940 } break;
1941
1942 case JVM_CONSTANT_InvokeDynamic:
1943 {
1944 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1945 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1946 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1947 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1948 } break;
1949
1950 // Invalid is used as the tag for the second constant pool entry
1951 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1952 // not be seen by itself.
1953 case JVM_CONSTANT_Invalid: // fall through
1954
1955 default:
1956 {
1957 ShouldNotReachHere();
1958 } break;
1959 }
1960 } // end copy_entry_to()
1961
1962 // Search constant pool search_cp for an entry that matches this
1963 // constant pool's entry at pattern_i. Returns the index of a
1964 // matching entry or zero (0) if there is no matching entry.
1965 int ConstantPool::find_matching_entry(int pattern_i,
1966 const constantPoolHandle& search_cp) {
1967
1968 // index zero (0) is not used
1969 for (int i = 1; i < search_cp->length(); i++) {
1970 bool found = compare_entry_to(pattern_i, search_cp, i);
1971 if (found) {
1972 return i;
1973 }
1974 }
1975
1976 return 0; // entry not found; return unused index zero (0)
1977 } // end find_matching_entry()
1978
1979
1980 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1981 // cp2's bootstrap specifier at idx2.
1982 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2) {
1983 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1984 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1985 bool match = compare_entry_to(k1, cp2, k2);
1986
1987 if (!match) {
1988 return false;
1989 }
1990 int argc = operand_argument_count_at(idx1);
1991 if (argc == cp2->operand_argument_count_at(idx2)) {
1992 for (int j = 0; j < argc; j++) {
1993 k1 = operand_argument_index_at(idx1, j);
1994 k2 = cp2->operand_argument_index_at(idx2, j);
1995 match = compare_entry_to(k1, cp2, k2);
1996 if (!match) {
1997 return false;
1998 }
1999 }
2000 return true; // got through loop; all elements equal
2001 }
2002 return false;
2003 } // end compare_operand_to()
2004
2005 // Search constant pool search_cp for a bootstrap specifier that matches
2006 // this constant pool's bootstrap specifier data at pattern_i index.
2007 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
2008 int ConstantPool::find_matching_operand(int pattern_i,
2009 const constantPoolHandle& search_cp, int search_len) {
2010 for (int i = 0; i < search_len; i++) {
2011 bool found = compare_operand_to(pattern_i, search_cp, i);
2012 if (found) {
2013 return i;
2014 }
2015 }
2016 return -1; // bootstrap specifier data not found; return unused index (-1)
2017 } // end find_matching_operand()
2018
2019
2020 #ifndef PRODUCT
2021
2022 const char* ConstantPool::printable_name_at(int cp_index) {
2023
2024 constantTag tag = tag_at(cp_index);
2025
2026 if (tag.is_string()) {
2027 return string_at_noresolve(cp_index);
2028 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
2029 return klass_name_at(cp_index)->as_C_string();
2030 } else if (tag.is_symbol()) {
2031 return symbol_at(cp_index)->as_C_string();
2032 }
2033 return "";
2034 }
2035
2036 #endif // PRODUCT
2037
2038
2039 // Returns size of constant pool entry.
2040 jint ConstantPool::cpool_entry_size(jint idx) {
2041 switch(tag_at(idx).value()) {
2042 case JVM_CONSTANT_Invalid:
2043 case JVM_CONSTANT_Unicode:
2044 return 1;
2045
2046 case JVM_CONSTANT_Utf8:
2047 return 3 + symbol_at(idx)->utf8_length();
2048
2049 case JVM_CONSTANT_Class:
2050 case JVM_CONSTANT_String:
2051 case JVM_CONSTANT_ClassIndex:
2052 case JVM_CONSTANT_UnresolvedClass:
2053 case JVM_CONSTANT_UnresolvedClassInError:
2054 case JVM_CONSTANT_StringIndex:
2055 case JVM_CONSTANT_MethodType:
2056 case JVM_CONSTANT_MethodTypeInError:
2057 return 3;
2058
2059 case JVM_CONSTANT_MethodHandle:
2060 case JVM_CONSTANT_MethodHandleInError:
2061 return 4; //tag, ref_kind, ref_index
2062
2063 case JVM_CONSTANT_Integer:
2064 case JVM_CONSTANT_Float:
2065 case JVM_CONSTANT_Fieldref:
2066 case JVM_CONSTANT_Methodref:
2067 case JVM_CONSTANT_InterfaceMethodref:
2068 case JVM_CONSTANT_NameAndType:
2069 return 5;
2070
2071 case JVM_CONSTANT_Dynamic:
2072 case JVM_CONSTANT_DynamicInError:
2073 case JVM_CONSTANT_InvokeDynamic:
2074 // u1 tag, u2 bsm, u2 nt
2075 return 5;
2076
2077 case JVM_CONSTANT_Long:
2078 case JVM_CONSTANT_Double:
2079 return 9;
2080 }
2081 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2082 return 1;
2083 } /* end cpool_entry_size */
2084
2085
2086 // SymbolHash is used to find a constant pool index from a string.
2087 // This function fills in SymbolHashs, one for utf8s and one for
2088 // class names, returns size of the cpool raw bytes.
2089 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
2090 SymbolHash *classmap) {
2091 jint size = 0;
2092
2093 for (u2 idx = 1; idx < length(); idx++) {
2094 u2 tag = tag_at(idx).value();
2095 size += cpool_entry_size(idx);
2096
2097 switch(tag) {
2098 case JVM_CONSTANT_Utf8: {
2099 Symbol* sym = symbol_at(idx);
2100 symmap->add_if_absent(sym, idx);
2101 break;
2102 }
2103 case JVM_CONSTANT_Class:
2104 case JVM_CONSTANT_UnresolvedClass:
2105 case JVM_CONSTANT_UnresolvedClassInError: {
2106 Symbol* sym = klass_name_at(idx);
2107 classmap->add_if_absent(sym, idx);
2108 break;
2109 }
2110 case JVM_CONSTANT_Long:
2111 case JVM_CONSTANT_Double: {
2112 idx++; // Both Long and Double take two cpool slots
2113 break;
2114 }
2115 }
2116 }
2117 return size;
2118 } /* end hash_utf8_entries_to */
2119
2120
2121 // Copy cpool bytes.
2122 // Returns:
2123 // 0, in case of OutOfMemoryError
2124 // -1, in case of internal error
2125 // > 0, count of the raw cpool bytes that have been copied
2126 int ConstantPool::copy_cpool_bytes(int cpool_size,
2127 SymbolHash* tbl,
2128 unsigned char *bytes) {
2129 u2 idx1, idx2;
2130 jint size = 0;
2131 jint cnt = length();
2132 unsigned char *start_bytes = bytes;
2133
2134 for (jint idx = 1; idx < cnt; idx++) {
2135 u1 tag = tag_at(idx).value();
2136 jint ent_size = cpool_entry_size(idx);
2137
2138 assert(size + ent_size <= cpool_size, "Size mismatch");
2139
2140 *bytes = tag;
2141 switch(tag) {
2142 case JVM_CONSTANT_Invalid: {
2143 break;
2144 }
2145 case JVM_CONSTANT_Unicode: {
2146 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2147 break;
2148 }
2149 case JVM_CONSTANT_Utf8: {
2150 Symbol* sym = symbol_at(idx);
2151 char* str = sym->as_utf8();
2152 // Warning! It's crashing on x86 with len = sym->utf8_length()
2153 int len = (int) strlen(str);
2154 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2155 for (int i = 0; i < len; i++) {
2156 bytes[3+i] = (u1) str[i];
2157 }
2158 break;
2159 }
2160 case JVM_CONSTANT_Integer: {
2161 jint val = int_at(idx);
2162 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2163 break;
2164 }
2165 case JVM_CONSTANT_Float: {
2166 jfloat val = float_at(idx);
2167 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2168 break;
2169 }
2170 case JVM_CONSTANT_Long: {
2171 jlong val = long_at(idx);
2172 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2173 idx++; // Long takes two cpool slots
2174 break;
2175 }
2176 case JVM_CONSTANT_Double: {
2177 jdouble val = double_at(idx);
2178 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2179 idx++; // Double takes two cpool slots
2180 break;
2181 }
2182 case JVM_CONSTANT_Class:
2183 case JVM_CONSTANT_UnresolvedClass:
2184 case JVM_CONSTANT_UnresolvedClassInError: {
2185 *bytes = JVM_CONSTANT_Class;
2186 Symbol* sym = klass_name_at(idx);
2187 idx1 = tbl->symbol_to_value(sym);
2188 assert(idx1 != 0, "Have not found a hashtable entry");
2189 Bytes::put_Java_u2((address) (bytes+1), idx1);
2190 break;
2191 }
2192 case JVM_CONSTANT_String: {
2193 *bytes = JVM_CONSTANT_String;
2194 Symbol* sym = unresolved_string_at(idx);
2195 idx1 = tbl->symbol_to_value(sym);
2196 assert(idx1 != 0, "Have not found a hashtable entry");
2197 Bytes::put_Java_u2((address) (bytes+1), idx1);
2198 break;
2199 }
2200 case JVM_CONSTANT_Fieldref:
2201 case JVM_CONSTANT_Methodref:
2202 case JVM_CONSTANT_InterfaceMethodref: {
2203 idx1 = uncached_klass_ref_index_at(idx);
2204 idx2 = uncached_name_and_type_ref_index_at(idx);
2205 Bytes::put_Java_u2((address) (bytes+1), idx1);
2206 Bytes::put_Java_u2((address) (bytes+3), idx2);
2207 break;
2208 }
2209 case JVM_CONSTANT_NameAndType: {
2210 idx1 = name_ref_index_at(idx);
2211 idx2 = signature_ref_index_at(idx);
2212 Bytes::put_Java_u2((address) (bytes+1), idx1);
2213 Bytes::put_Java_u2((address) (bytes+3), idx2);
2214 break;
2215 }
2216 case JVM_CONSTANT_ClassIndex: {
2217 *bytes = JVM_CONSTANT_Class;
2218 idx1 = checked_cast<u2>(klass_index_at(idx));
2219 Bytes::put_Java_u2((address) (bytes+1), idx1);
2220 break;
2221 }
2222 case JVM_CONSTANT_StringIndex: {
2223 *bytes = JVM_CONSTANT_String;
2224 idx1 = checked_cast<u2>(string_index_at(idx));
2225 Bytes::put_Java_u2((address) (bytes+1), idx1);
2226 break;
2227 }
2228 case JVM_CONSTANT_MethodHandle:
2229 case JVM_CONSTANT_MethodHandleInError: {
2230 *bytes = JVM_CONSTANT_MethodHandle;
2231 int kind = method_handle_ref_kind_at(idx);
2232 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2233 *(bytes+1) = (unsigned char) kind;
2234 Bytes::put_Java_u2((address) (bytes+2), idx1);
2235 break;
2236 }
2237 case JVM_CONSTANT_MethodType:
2238 case JVM_CONSTANT_MethodTypeInError: {
2239 *bytes = JVM_CONSTANT_MethodType;
2240 idx1 = checked_cast<u2>(method_type_index_at(idx));
2241 Bytes::put_Java_u2((address) (bytes+1), idx1);
2242 break;
2243 }
2244 case JVM_CONSTANT_Dynamic:
2245 case JVM_CONSTANT_DynamicInError: {
2246 *bytes = tag;
2247 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2248 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2249 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2250 Bytes::put_Java_u2((address) (bytes+1), idx1);
2251 Bytes::put_Java_u2((address) (bytes+3), idx2);
2252 break;
2253 }
2254 case JVM_CONSTANT_InvokeDynamic: {
2255 *bytes = tag;
2256 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2257 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2258 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2259 Bytes::put_Java_u2((address) (bytes+1), idx1);
2260 Bytes::put_Java_u2((address) (bytes+3), idx2);
2261 break;
2262 }
2263 }
2264 bytes += ent_size;
2265 size += ent_size;
2266 }
2267 assert(size == cpool_size, "Size mismatch");
2268
2269 return (int)(bytes - start_bytes);
2270 } /* end copy_cpool_bytes */
2271
2272 bool ConstantPool::is_maybe_on_stack() const {
2273 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2274 if (!Continuations::enabled()) {
2275 return false;
2276 }
2277
2278 // If the condition below is true, it means that the nmethod was found to
2279 // be alive the previous completed marking cycle.
2280 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2281 }
2282
2283 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2284 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2285 // memory for the method is reclaimed.
2286 bool ConstantPool::on_stack() const {
2287 if ((_flags &_on_stack) != 0) {
2288 return true;
2289 }
2290
2291 if (_cache == nullptr) {
2292 return false;
2293 }
2294
2295 return is_maybe_on_stack();
2296 }
2297
2298 void ConstantPool::set_on_stack(const bool value) {
2299 if (value) {
2300 // Only record if it's not already set.
2301 if (!on_stack()) {
2302 assert(!is_shared(), "should always be set for shared constant pools");
2303 _flags |= _on_stack;
2304 MetadataOnStackMark::record(this);
2305 }
2306 } else {
2307 // Clearing is done single-threadedly.
2308 if (!is_shared()) {
2309 _flags &= (u2)(~_on_stack);
2310 }
2311 }
2312 }
2313
2314 // Printing
2315
2316 void ConstantPool::print_on(outputStream* st) const {
2317 assert(is_constantPool(), "must be constantPool");
2318 st->print_cr("%s", internal_name());
2319 if (flags() != 0) {
2320 st->print(" - flags: 0x%x", flags());
2321 if (has_preresolution()) st->print(" has_preresolution");
2322 if (on_stack()) st->print(" on_stack");
2323 st->cr();
2324 }
2325 if (pool_holder() != nullptr) {
2326 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2327 }
2328 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2329 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2330 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2331 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2332 st->print_cr(" - cp length: %d", length());
2333
2334 for (int index = 1; index < length(); index++) { // Index 0 is unused
2335 ((ConstantPool*)this)->print_entry_on(index, st);
2336 switch (tag_at(index).value()) {
2337 case JVM_CONSTANT_Long :
2338 case JVM_CONSTANT_Double :
2339 index++; // Skip entry following eigth-byte constant
2340 }
2341
2342 }
2343 st->cr();
2344 }
2345
2346 // Print one constant pool entry
2347 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2348 EXCEPTION_MARK;
2349 st->print(" - %3d : ", cp_index);
2350 tag_at(cp_index).print_on(st);
2351 st->print(" : ");
2352 switch (tag_at(cp_index).value()) {
2353 case JVM_CONSTANT_Class :
2354 { Klass* k = klass_at(cp_index, CATCH);
2355 guarantee(k != nullptr, "need klass");
2356 k->print_value_on(st);
2357 st->print(" {" PTR_FORMAT "}", p2i(k));
2358 }
2359 break;
2360 case JVM_CONSTANT_Fieldref :
2361 case JVM_CONSTANT_Methodref :
2362 case JVM_CONSTANT_InterfaceMethodref :
2363 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2364 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2365 break;
2366 case JVM_CONSTANT_String :
2367 unresolved_string_at(cp_index)->print_value_on(st);
2368 break;
2369 case JVM_CONSTANT_Integer :
2370 st->print("%d", int_at(cp_index));
2371 break;
2372 case JVM_CONSTANT_Float :
2373 st->print("%f", float_at(cp_index));
2374 break;
2375 case JVM_CONSTANT_Long :
2376 st->print_jlong(long_at(cp_index));
2377 break;
2378 case JVM_CONSTANT_Double :
2379 st->print("%lf", double_at(cp_index));
2380 break;
2381 case JVM_CONSTANT_NameAndType :
2382 st->print("name_index=%d", name_ref_index_at(cp_index));
2383 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2384 break;
2385 case JVM_CONSTANT_Utf8 :
2386 symbol_at(cp_index)->print_value_on(st);
2387 break;
2388 case JVM_CONSTANT_ClassIndex: {
2389 int name_index = *int_at_addr(cp_index);
2390 st->print("klass_index=%d ", name_index);
2391 symbol_at(name_index)->print_value_on(st);
2392 }
2393 break;
2394 case JVM_CONSTANT_UnresolvedClass : // fall-through
2395 case JVM_CONSTANT_UnresolvedClassInError: {
2396 CPKlassSlot kslot = klass_slot_at(cp_index);
2397 int resolved_klass_index = kslot.resolved_klass_index();
2398 int name_index = kslot.name_index();
2399 assert(tag_at(name_index).is_symbol(), "sanity");
2400 symbol_at(name_index)->print_value_on(st);
2401 }
2402 break;
2403 case JVM_CONSTANT_MethodHandle :
2404 case JVM_CONSTANT_MethodHandleInError :
2405 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2406 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2407 break;
2408 case JVM_CONSTANT_MethodType :
2409 case JVM_CONSTANT_MethodTypeInError :
2410 st->print("signature_index=%d", method_type_index_at(cp_index));
2411 break;
2412 case JVM_CONSTANT_Dynamic :
2413 case JVM_CONSTANT_DynamicInError :
2414 {
2415 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2416 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2417 int argc = bootstrap_argument_count_at(cp_index);
2418 if (argc > 0) {
2419 for (int arg_i = 0; arg_i < argc; arg_i++) {
2420 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2421 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2422 }
2423 st->print("}");
2424 }
2425 }
2426 break;
2427 case JVM_CONSTANT_InvokeDynamic :
2428 {
2429 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2430 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2431 int argc = bootstrap_argument_count_at(cp_index);
2432 if (argc > 0) {
2433 for (int arg_i = 0; arg_i < argc; arg_i++) {
2434 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2435 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2436 }
2437 st->print("}");
2438 }
2439 }
2440 break;
2441 default:
2442 ShouldNotReachHere();
2443 break;
2444 }
2445 st->cr();
2446 }
2447
2448 void ConstantPool::print_value_on(outputStream* st) const {
2449 assert(is_constantPool(), "must be constantPool");
2450 st->print("constant pool [%d]", length());
2451 if (has_preresolution()) st->print("/preresolution");
2452 if (operands() != nullptr) st->print("/operands[%d]", operands()->length());
2453 print_address_on(st);
2454 if (pool_holder() != nullptr) {
2455 st->print(" for ");
2456 pool_holder()->print_value_on(st);
2457 bool extra = (pool_holder()->constants() != this);
2458 if (extra) st->print(" (extra)");
2459 }
2460 if (cache() != nullptr) {
2461 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2462 }
2463 }
2464
2465 // Verification
2466
2467 void ConstantPool::verify_on(outputStream* st) {
2468 guarantee(is_constantPool(), "object must be constant pool");
2469 for (int i = 0; i< length(); i++) {
2470 constantTag tag = tag_at(i);
2471 if (tag.is_klass() || tag.is_unresolved_klass()) {
2472 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2473 } else if (tag.is_symbol()) {
2474 Symbol* entry = symbol_at(i);
2475 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2476 } else if (tag.is_string()) {
2477 Symbol* entry = unresolved_string_at(i);
2478 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2479 }
2480 }
2481 if (pool_holder() != nullptr) {
2482 // Note: pool_holder() can be null in temporary constant pools
2483 // used during constant pool merging
2484 guarantee(pool_holder()->is_klass(), "should be klass");
2485 }
2486 }