1 /*
2 * Copyright (c) 1997, 2024, 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 "precompiled.hpp"
26 #include "cds/aotConstantPoolResolver.hpp"
27 #include "cds/archiveBuilder.hpp"
28 #include "cds/archiveHeapLoader.hpp"
29 #include "cds/archiveHeapWriter.hpp"
30 #include "cds/cdsConfig.hpp"
31 #include "cds/heapShared.hpp"
32 #include "classfile/classLoader.hpp"
33 #include "classfile/classLoaderData.hpp"
34 #include "classfile/javaClasses.inline.hpp"
35 #include "classfile/metadataOnStackMark.hpp"
36 #include "classfile/stringTable.hpp"
37 #include "classfile/systemDictionary.hpp"
38 #include "classfile/systemDictionaryShared.hpp"
39 #include "classfile/vmClasses.hpp"
40 #include "classfile/vmSymbols.hpp"
41 #include "code/codeCache.hpp"
42 #include "interpreter/bootstrapInfo.hpp"
43 #include "interpreter/linkResolver.hpp"
44 #include "jvm.h"
45 #include "logging/log.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/metadataFactory.hpp"
49 #include "memory/metaspaceClosure.hpp"
50 #include "memory/oopFactory.hpp"
51 #include "memory/resourceArea.hpp"
52 #include "memory/universe.hpp"
53 #include "oops/array.hpp"
54 #include "oops/constantPool.inline.hpp"
55 #include "oops/cpCache.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/handles.inline.hpp"
65 #include "runtime/init.hpp"
66 #include "runtime/javaCalls.hpp"
67 #include "runtime/javaThread.inline.hpp"
68 #include "runtime/perfData.hpp"
69 #include "runtime/signature.hpp"
70 #include "runtime/vframe.inline.hpp"
71 #include "utilities/checkedCast.hpp"
72 #include "utilities/copy.hpp"
73
74 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
75 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
76 int size = ConstantPool::size(length);
77 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
78 }
79
80 void ConstantPool::copy_fields(const ConstantPool* orig) {
81 // Preserve dynamic constant information from the original pool
82 if (orig->has_dynamic_constant()) {
83 set_has_dynamic_constant();
84 }
85
86 set_major_version(orig->major_version());
87 set_minor_version(orig->minor_version());
88
89 set_source_file_name_index(orig->source_file_name_index());
90 set_generic_signature_index(orig->generic_signature_index());
91 }
92
93 #ifdef ASSERT
94
95 // MetaspaceObj allocation invariant is calloc equivalent memory
96 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
97 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
98 assert(tags != nullptr, "invariant");
99 const int length = tags->length();
100 for (int index = 0; index < length; ++index) {
101 if (JVM_CONSTANT_Invalid != tags->at(index)) {
102 return false;
103 }
104 }
105 return true;
106 }
107
108 #endif
109
110 ConstantPool::ConstantPool() {
111 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
112 }
113
114 ConstantPool::ConstantPool(Array<u1>* tags) :
115 _tags(tags),
116 _length(tags->length()) {
117
118 assert(_tags != nullptr, "invariant");
119 assert(tags->length() == _length, "invariant");
120 assert(tag_array_is_zero_initialized(tags), "invariant");
121 assert(0 == flags(), "invariant");
122 assert(0 == version(), "invariant");
123 assert(nullptr == _pool_holder, "invariant");
124 }
125
126 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
127 if (cache() != nullptr) {
128 MetadataFactory::free_metadata(loader_data, cache());
129 set_cache(nullptr);
130 }
131
132 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
133 set_resolved_klasses(nullptr);
134
135 MetadataFactory::free_array<jushort>(loader_data, operands());
136 set_operands(nullptr);
137
138 release_C_heap_structures();
139
140 // free tag array
141 MetadataFactory::free_array<u1>(loader_data, tags());
142 set_tags(nullptr);
143 }
144
145 void ConstantPool::release_C_heap_structures() {
146 // walk constant pool and decrement symbol reference counts
147 unreference_symbols();
148 }
149
150 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
151 log_trace(cds)("Iter(ConstantPool): %p", this);
152
153 it->push(&_tags, MetaspaceClosure::_writable);
154 it->push(&_cache);
155 it->push(&_pool_holder);
156 it->push(&_operands);
157 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
158
159 for (int i = 0; i < length(); i++) {
160 // The only MSO's embedded in the CP entries are Symbols:
161 // JVM_CONSTANT_String
162 // JVM_CONSTANT_Utf8
163 constantTag ctag = tag_at(i);
164 if (ctag.is_string() || ctag.is_utf8()) {
165 it->push(symbol_at_addr(i));
166 }
167 }
168 }
169
170 objArrayOop ConstantPool::resolved_references() const {
171 return _cache->resolved_references();
172 }
173
174 // Called from outside constant pool resolution where a resolved_reference array
175 // may not be present.
176 objArrayOop ConstantPool::resolved_references_or_null() const {
177 if (_cache == nullptr) {
178 return nullptr;
179 } else {
180 return _cache->resolved_references();
181 }
182 }
183
184 oop ConstantPool::resolved_reference_at(int index) const {
185 oop result = resolved_references()->obj_at(index);
186 assert(oopDesc::is_oop_or_null(result), "Must be oop");
187 return result;
188 }
189
190 // Use a CAS for multithreaded access
191 oop ConstantPool::set_resolved_reference_at(int index, oop new_result) {
192 assert(oopDesc::is_oop_or_null(new_result), "Must be oop");
193 return resolved_references()->replace_if_null(index, new_result);
194 }
195
196 // Create resolved_references array and mapping array for original cp indexes
197 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
198 // to map it back for resolving and some unlikely miscellaneous uses.
199 // The objects created by invokedynamic are appended to this list.
200 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
201 const intStack& reference_map,
202 int constant_pool_map_length,
203 TRAPS) {
204 // Initialized the resolved object cache.
205 int map_length = reference_map.length();
206 if (map_length > 0) {
207 // Only need mapping back to constant pool entries. The map isn't used for
208 // invokedynamic resolved_reference entries. For invokedynamic entries,
209 // the constant pool cache index has the mapping back to both the constant
210 // pool and to the resolved reference index.
211 if (constant_pool_map_length > 0) {
212 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
213
214 for (int i = 0; i < constant_pool_map_length; i++) {
215 int x = reference_map.at(i);
216 assert(x == (int)(jushort) x, "klass index is too big");
217 om->at_put(i, (jushort)x);
218 }
219 set_reference_map(om);
220 }
221
222 // Create Java array for holding resolved strings, methodHandles,
223 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
224 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
225 HandleMark hm(THREAD);
226 Handle refs_handle (THREAD, stom); // must handleize.
227 set_resolved_references(loader_data->add_handle(refs_handle));
228
229 // Create a "scratch" copy of the resolved references array to archive
230 if (CDSConfig::is_dumping_heap()) {
231 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
232 HeapShared::add_scratch_resolved_references(this, scratch_references);
233 }
234 }
235 }
236
237 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
238 // A ConstantPool can't possibly have 0xffff valid class entries,
239 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
240 // entry for the class's name. So at most we will have 0xfffe class entries.
241 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
242 // UnresolvedKlass entries that are temporarily created during class redefinition.
243 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
244 assert(resolved_klasses() == nullptr, "sanity");
245 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
246 set_resolved_klasses(rk);
247 }
248
249 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
250 int len = length();
251 int num_klasses = 0;
252 for (int i = 1; i <len; i++) {
253 switch (tag_at(i).value()) {
254 case JVM_CONSTANT_ClassIndex:
255 {
256 const int class_index = klass_index_at(i);
257 unresolved_klass_at_put(i, class_index, num_klasses++);
258 }
259 break;
260 #ifndef PRODUCT
261 case JVM_CONSTANT_Class:
262 case JVM_CONSTANT_UnresolvedClass:
263 case JVM_CONSTANT_UnresolvedClassInError:
264 // All of these should have been reverted back to ClassIndex before calling
265 // this function.
266 ShouldNotReachHere();
267 #endif
268 }
269 }
270 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
271 }
272
273 // Hidden class support:
274 void ConstantPool::klass_at_put(int class_index, Klass* k) {
275 assert(k != nullptr, "must be valid klass");
276 CPKlassSlot kslot = klass_slot_at(class_index);
277 int resolved_klass_index = kslot.resolved_klass_index();
278 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
279 Atomic::release_store(adr, k);
280
281 // The interpreter assumes when the tag is stored, the klass is resolved
282 // and the Klass* non-null, so we need hardware store ordering here.
283 release_tag_at_put(class_index, JVM_CONSTANT_Class);
284 }
285
286 #if INCLUDE_CDS_JAVA_HEAP
287 template <typename Function>
288 void ConstantPool::iterate_archivable_resolved_references(Function function) {
289 objArrayOop rr = resolved_references();
290 if (rr != nullptr && cache() != nullptr && CDSConfig::is_dumping_invokedynamic()) {
291 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
292 if (indy_entries != nullptr) {
293 for (int i = 0; i < indy_entries->length(); i++) {
294 ResolvedIndyEntry *rie = indy_entries->adr_at(i);
295 if (rie->is_resolved() && AOTConstantPoolResolver::is_resolution_deterministic(this, rie->constant_pool_index())) {
296 int rr_index = rie->resolved_references_index();
297 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
298 function(rr_index);
299
300 // Save the BSM as well (sometimes the JIT looks up the BSM it for replay)
301 int indy_cp_index = rie->constant_pool_index();
302 int bsm_mh_cp_index = bootstrap_method_ref_index_at(indy_cp_index);
303 int bsm_rr_index = cp_to_object_index(bsm_mh_cp_index);
304 assert(resolved_reference_at(bsm_rr_index) != nullptr, "must exist");
305 function(bsm_rr_index);
306 }
307 }
308 }
309
310 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
311 if (method_entries != nullptr) {
312 for (int i = 0; i < method_entries->length(); i++) {
313 ResolvedMethodEntry* rme = method_entries->adr_at(i);
314 if (rme->is_resolved(Bytecodes::_invokehandle) && rme->has_appendix() &&
315 cache()->can_archive_resolved_method(this, rme)) {
316 int rr_index = rme->resolved_references_index();
317 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
318 function(rr_index);
319 }
320 }
321 }
322 }
323 }
324
325 // Returns the _resolved_reference array after removing unarchivable items from it.
326 // Returns null if this class is not supported, or _resolved_reference doesn't exist.
327 objArrayOop ConstantPool::prepare_resolved_references_for_archiving() {
328 if (_cache == nullptr) {
329 return nullptr; // nothing to do
330 }
331
332 InstanceKlass *ik = pool_holder();
333 if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
334 ik->is_shared_app_class())) {
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 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
347 src_cp->iterate_archivable_resolved_references([&](int rr_index) {
348 keep_resolved_refs.at_put(rr_index, true);
349 });
350
351 objArrayOop scratch_rr = HeapShared::scratch_resolved_references(src_cp);
352 Array<u2>* ref_map = reference_map();
353 int ref_map_len = ref_map == nullptr ? 0 : ref_map->length();
354 for (int i = 0; i < rr_len; i++) {
355 oop obj = rr->obj_at(i);
356 scratch_rr->obj_at_put(i, nullptr);
357 if (obj != nullptr) {
358 if (i < ref_map_len) {
359 int index = object_to_cp_index(i);
360 if (tag_at(index).is_string()) {
361 assert(java_lang_String::is_instance(obj), "must be");
362 if (!ArchiveHeapWriter::is_string_too_large_to_archive(obj)) {
363 scratch_rr->obj_at_put(i, obj);
364 }
365 continue;
366 }
367 }
368
369 if (keep_resolved_refs.at(i)) {
370 scratch_rr->obj_at_put(i, obj);
371 }
372 }
373 }
374 return scratch_rr;
375 }
376 return rr;
377 }
378
379 void ConstantPool::find_required_hidden_classes() {
380 if (_cache == nullptr) {
381 return;
382 }
383
384 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
385 if (loader_data == nullptr) {
386 // These are custom loader classes from the preimage
387 return;
388 }
389
390 if (!SystemDictionaryShared::is_builtin_loader(loader_data)) {
391 // Archiving resolved references for classes from non-builtin loaders
392 // is not yet supported.
393 return;
394 }
395
396 objArrayOop rr = resolved_references();
397 if (rr != nullptr) {
398 iterate_archivable_resolved_references([&](int rr_index) {
399 oop obj = rr->obj_at(rr_index);
400 HeapShared::find_required_hidden_classes_in_object(obj);
401 });
402 }
403 }
404
405 void ConstantPool::add_dumped_interned_strings() {
406 objArrayOop rr = resolved_references();
407 if (rr != nullptr) {
408 int rr_len = rr->length();
409 for (int i = 0; i < rr_len; i++) {
410 oop p = rr->obj_at(i);
411 if (java_lang_String::is_instance(p) &&
412 !ArchiveHeapWriter::is_string_too_large_to_archive(p)) {
413 HeapShared::add_to_dumped_interned_strings(p);
414 }
415 }
416 }
417 }
418 #endif
419
420 #if INCLUDE_CDS
421 // CDS support. Create a new resolved_references array.
422 void ConstantPool::restore_unshareable_info(TRAPS) {
423 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
424 return;
425 }
426 assert(is_constantPool(), "ensure C++ vtable is restored");
427 assert(on_stack(), "should always be set for shared constant pools");
428 assert(is_shared(), "should always be set for shared constant pools");
429 if (is_for_method_handle_intrinsic()) {
430 // See the same check in remove_unshareable_info() below.
431 assert(cache() == NULL, "must not have cpCache");
432 return;
433 }
434 assert(_cache != nullptr, "constant pool _cache should not be null");
435
436 // Only create the new resolved references array if it hasn't been attempted before
437 if (resolved_references() != nullptr) return;
438
439 if (vmClasses::Object_klass_loaded()) {
440 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
441 #if INCLUDE_CDS_JAVA_HEAP
442 if (ArchiveHeapLoader::is_in_use() &&
443 _cache->archived_references() != nullptr) {
444 oop archived = _cache->archived_references();
445 // Create handle for the archived resolved reference array object
446 HandleMark hm(THREAD);
447 Handle refs_handle(THREAD, archived);
448 set_resolved_references(loader_data->add_handle(refs_handle));
449 _cache->clear_archived_references();
450 } else
451 #endif
452 {
453 // No mapped archived resolved reference array
454 // Recreate the object array and add to ClassLoaderData.
455 int map_length = resolved_reference_length();
456 if (map_length > 0) {
457 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
458 HandleMark hm(THREAD);
459 Handle refs_handle(THREAD, stom); // must handleize.
460 set_resolved_references(loader_data->add_handle(refs_handle));
461 }
462 }
463 }
464 }
465
466 void ConstantPool::remove_unshareable_info() {
467 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
468 // The _on_stack flag is used to prevent ConstantPools from deallocation during
469 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
470 // we always set _on_stack to true to avoid having to change _flags during runtime.
471 _flags |= (_on_stack | _is_shared);
472
473 if (is_for_method_handle_intrinsic()) {
474 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
475 // that need to be removed/restored. It has no cpCache since the intrinsic methods
476 // don't have any bytecodes.
477 assert(cache() == NULL, "must not have cpCache");
478 return;
479 }
480
481 // resolved_references(): remember its length. If it cannot be restored
482 // from the archived heap objects at run time, we need to dynamically allocate it.
483 if (cache() != nullptr) {
484 set_resolved_reference_length(
485 resolved_references() != nullptr ? resolved_references()->length() : 0);
486 set_resolved_references(OopHandle());
487 }
488 remove_unshareable_entries();
489 }
490
491 static const char* get_type(Klass* k) {
492 const char* type;
493 Klass* src_k;
494 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
495 src_k = ArchiveBuilder::current()->get_source_addr(k);
496 } else {
497 src_k = k;
498 }
499
500 if (src_k->is_objArray_klass()) {
501 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
502 assert(!src_k->is_objArray_klass(), "sanity");
503 }
504
505 if (src_k->is_typeArray_klass()) {
506 type = "prim";
507 } else {
508 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
509 oop loader = src_ik->class_loader();
510 if (loader == nullptr) {
511 type = "boot";
512 } else if (loader == SystemDictionary::java_platform_loader()) {
513 type = "plat";
514 } else if (loader == SystemDictionary::java_system_loader()) {
515 type = "app";
516 } else {
517 type = "unreg";
518 }
519 }
520
521 return type;
522 }
523
524 void ConstantPool::remove_unshareable_entries() {
525 ResourceMark rm;
526 log_info(cds, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
527 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
528 int cp_tag = tag_at(cp_index).value();
529 switch (cp_tag) {
530 case JVM_CONSTANT_UnresolvedClass:
531 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, false);
532 break;
533 case JVM_CONSTANT_UnresolvedClassInError:
534 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
535 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, true);
536 break;
537 case JVM_CONSTANT_MethodHandleInError:
538 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
539 break;
540 case JVM_CONSTANT_MethodTypeInError:
541 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
542 break;
543 case JVM_CONSTANT_DynamicInError:
544 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
545 break;
546 case JVM_CONSTANT_Class:
547 remove_resolved_klass_if_non_deterministic(cp_index);
548 break;
549 default:
550 break;
551 }
552 }
553
554 if (cache() != nullptr) {
555 // cache() is null if this class is not yet linked.
556 cache()->remove_unshareable_info();
557 }
558 }
559
560 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
561 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
562 assert(tag_at(cp_index).is_klass(), "must be resolved");
563
564 Klass* k = resolved_klass_at(cp_index);
565 bool can_archive;
566
567 if (k == nullptr) {
568 // We'd come here if the referenced class has been excluded via
569 // SystemDictionaryShared::is_excluded_class(). As a result, ArchiveBuilder
570 // has cleared the resolved_klasses()->at(...) pointer to null. Thus, we
571 // need to revert the tag to JVM_CONSTANT_UnresolvedClass.
572 can_archive = false;
573 } else {
574 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
575 can_archive = AOTConstantPoolResolver::is_resolution_deterministic(src_cp, cp_index);
576 }
577
578 if (!can_archive) {
579 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
580 resolved_klasses()->at_put(resolved_klass_index, nullptr);
581 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
582 }
583
584 LogStreamHandle(Trace, cds, resolve) log;
585 if (log.is_enabled()) {
586 ResourceMark rm;
587 log.print("%s klass CP entry [%3d]: %s %s",
588 (can_archive ? "archived" : "reverted"),
589 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
590 if (can_archive) {
591 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
592 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
593 } else {
594 Symbol* name = klass_name_at(cp_index);
595 log.print(" => %s", name->as_C_string());
596 }
597 }
598
599 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(can_archive, /*reverted=*/!can_archive);
600 }
601 #endif // INCLUDE_CDS
602
603 int ConstantPool::cp_to_object_index(int cp_index) {
604 // this is harder don't do this so much.
605 int i = reference_map()->find(checked_cast<u2>(cp_index));
606 // We might not find the index for jsr292 call.
607 return (i < 0) ? _no_index_sentinel : i;
608 }
609
610 void ConstantPool::string_at_put(int obj_index, oop str) {
611 oop result = set_resolved_reference_at(obj_index, str);
612 assert(result == nullptr || result == str, "Only set once or to the same string.");
613 }
614
615 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
616 ResourceMark rm;
617 int line_number = -1;
618 const char * source_file = nullptr;
619 if (JavaThread::current()->has_last_Java_frame()) {
620 // try to identify the method which called this function.
621 vframeStream vfst(JavaThread::current());
622 if (!vfst.at_end()) {
623 line_number = vfst.method()->line_number_from_bci(vfst.bci());
624 Symbol* s = vfst.method()->method_holder()->source_file_name();
625 if (s != nullptr) {
626 source_file = s->as_C_string();
627 }
628 }
629 }
630 if (k != this_cp->pool_holder()) {
631 // only print something if the classes are different
632 if (source_file != nullptr) {
633 log_debug(class, resolve)("%s %s %s:%d",
634 this_cp->pool_holder()->external_name(),
635 k->external_name(), source_file, line_number);
636 } else {
637 log_debug(class, resolve)("%s %s",
638 this_cp->pool_holder()->external_name(),
639 k->external_name());
640 }
641 }
642 }
643
644 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
645 TRAPS) {
646 JavaThread* javaThread = THREAD;
647
648 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
649 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
650 // the entry and tag is not updated atomically.
651 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
652 int resolved_klass_index = kslot.resolved_klass_index();
653 int name_index = kslot.name_index();
654 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
655
656 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
657 // the unresolved_klasses() array.
658 if (this_cp->tag_at(cp_index).is_klass()) {
659 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
660 if (klass != nullptr) {
661 return klass;
662 }
663 }
664
665 // This tag doesn't change back to unresolved class unless at a safepoint.
666 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
667 // The original attempt to resolve this constant pool entry failed so find the
668 // class of the original error and throw another error of the same class
669 // (JVMS 5.4.3).
670 // If there is a detail message, pass that detail message to the error.
671 // The JVMS does not strictly require us to duplicate the same detail message,
672 // or any internal exception fields such as cause or stacktrace. But since the
673 // detail message is often a class name or other literal string, we will repeat it
674 // if we can find it in the symbol table.
675 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
676 ShouldNotReachHere();
677 }
678
679 HandleMark hm(THREAD);
680 Handle mirror_handle;
681 Symbol* name = this_cp->symbol_at(name_index);
682 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
683 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
684
685 Klass* k;
686 {
687 // Turn off the single stepping while doing class resolution
688 JvmtiHideSingleStepping jhss(javaThread);
689 k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
690 } // JvmtiHideSingleStepping jhss(javaThread);
691
692 if (!HAS_PENDING_EXCEPTION) {
693 // preserve the resolved klass from unloading
694 mirror_handle = Handle(THREAD, k->java_mirror());
695 // Do access check for klasses
696 verify_constant_pool_resolve(this_cp, k, THREAD);
697 }
698
699 // Failed to resolve class. We must record the errors so that subsequent attempts
700 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
701 if (HAS_PENDING_EXCEPTION) {
702 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
703 // If CHECK_NULL above doesn't return the exception, that means that
704 // some other thread has beaten us and has resolved the class.
705 // To preserve old behavior, we return the resolved class.
706 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
707 assert(klass != nullptr, "must be resolved if exception was cleared");
708 return klass;
709 }
710
711 // logging for class+resolve.
712 if (log_is_enabled(Debug, class, resolve)){
713 trace_class_resolution(this_cp, k);
714 }
715
716 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
717 Atomic::release_store(adr, k);
718 // The interpreter assumes when the tag is stored, the klass is resolved
719 // and the Klass* stored in _resolved_klasses is non-null, so we need
720 // hardware store ordering here.
721 // We also need to CAS to not overwrite an error from a racing thread.
722
723 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
724 (jbyte)JVM_CONSTANT_UnresolvedClass,
725 (jbyte)JVM_CONSTANT_Class);
726
727 // We need to recheck exceptions from racing thread and return the same.
728 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
729 // Remove klass.
730 this_cp->resolved_klasses()->at_put(resolved_klass_index, nullptr);
731 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
732 }
733
734 return k;
735 }
736
737
738 // Does not update ConstantPool* - to avoid any exception throwing. Used
739 // by compiler and exception handling. Also used to avoid classloads for
740 // instanceof operations. Returns null if the class has not been loaded or
741 // if the verification of constant pool failed
742 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
743 CPKlassSlot kslot = this_cp->klass_slot_at(which);
744 int resolved_klass_index = kslot.resolved_klass_index();
745 int name_index = kslot.name_index();
746 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
747
748 if (this_cp->tag_at(which).is_klass()) {
749 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
750 assert(k != nullptr, "should be resolved");
751 return k;
752 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
753 return nullptr;
754 } else {
755 Thread* current = Thread::current();
756 HandleMark hm(current);
757 Symbol* name = this_cp->symbol_at(name_index);
758 oop loader = this_cp->pool_holder()->class_loader();
759 oop protection_domain = this_cp->pool_holder()->protection_domain();
760 Handle h_prot (current, protection_domain);
761 Handle h_loader (current, loader);
762 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader, h_prot);
763
764 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
765 if (k != nullptr && current->is_Java_thread()) {
766 // Make sure that resolving is legal
767 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
768 ExceptionMark em(THREAD);
769 // return null if verification fails
770 verify_constant_pool_resolve(this_cp, k, THREAD);
771 if (HAS_PENDING_EXCEPTION) {
772 CLEAR_PENDING_EXCEPTION;
773 return nullptr;
774 }
775 return k;
776 } else {
777 return k;
778 }
779 }
780 }
781
782 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
783 int which) {
784 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
785 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
786 // FIXME: should be an assert
787 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
788 return nullptr;
789 }
790 return cpool->cache()->method_if_resolved(which);
791 }
792
793
794 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
795 if (cpool->cache() == nullptr) return false; // nothing to load yet
796 if (code == Bytecodes::_invokedynamic) {
797 return cpool->resolved_indy_entry_at(which)->has_appendix();
798 } else {
799 return cpool->resolved_method_entry_at(which)->has_appendix();
800 }
801 }
802
803 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
804 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
805 if (code == Bytecodes::_invokedynamic) {
806 return cpool->resolved_reference_from_indy(which);
807 } else {
808 return cpool->cache()->appendix_if_resolved(which);
809 }
810 }
811
812
813 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
814 if (cpool->cache() == nullptr) return false; // nothing to load yet
815 if (code == Bytecodes::_invokedynamic) {
816 return cpool->resolved_indy_entry_at(which)->has_local_signature();
817 } else {
818 return cpool->resolved_method_entry_at(which)->has_local_signature();
819 }
820 }
821
822 // Translate index, which could be CPCache index or Indy index, to a constant pool index
823 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
824 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
825 switch(code) {
826 case Bytecodes::_invokedynamic:
827 return invokedynamic_bootstrap_ref_index_at(index);
828 case Bytecodes::_getfield:
829 case Bytecodes::_getstatic:
830 case Bytecodes::_putfield:
831 case Bytecodes::_putstatic:
832 return resolved_field_entry_at(index)->constant_pool_index();
833 case Bytecodes::_invokeinterface:
834 case Bytecodes::_invokehandle:
835 case Bytecodes::_invokespecial:
836 case Bytecodes::_invokestatic:
837 case Bytecodes::_invokevirtual:
838 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
839 return resolved_method_entry_at(index)->constant_pool_index();
840 default:
841 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
842 }
843 }
844
845 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
846 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
847 switch(code) {
848 case Bytecodes::_invokedynamic:
849 return resolved_indy_entry_at(index)->is_resolved();
850
851 case Bytecodes::_getfield:
852 case Bytecodes::_getstatic:
853 case Bytecodes::_putfield:
854 case Bytecodes::_putstatic:
855 return resolved_field_entry_at(index)->is_resolved(code);
856
857 case Bytecodes::_invokeinterface:
858 case Bytecodes::_invokehandle:
859 case Bytecodes::_invokespecial:
860 case Bytecodes::_invokestatic:
861 case Bytecodes::_invokevirtual:
862 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
863 return resolved_method_entry_at(index)->is_resolved(code);
864
865 default:
866 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
867 }
868 }
869
870 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
871 if (tag_at(cp_index).has_bootstrap()) {
872 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
873 assert(tag_at(pool_index).is_name_and_type(), "");
874 return pool_index;
875 }
876 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
877 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
878 jint ref_index = *int_at_addr(cp_index);
879 return extract_high_short_from_int(ref_index);
880 }
881
882 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
883 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
884 }
885
886 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
887 // which may be either a Constant Pool index or a rewritten index
888 int pool_index = which;
889 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
890 pool_index = to_cp_index(which, code);
891 return tag_at(pool_index);
892 }
893
894 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
895 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
896 jint ref_index = *int_at_addr(cp_index);
897 return extract_low_short_from_int(ref_index);
898 }
899
900 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
901 assert(code != Bytecodes::_invokedynamic,
902 "an invokedynamic instruction does not have a klass");
903 return uncached_klass_ref_index_at(to_cp_index(index, code));
904 }
905
906 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
907 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
908 return; // short cut, typeArray klass is always accessible
909 }
910 Klass* holder = this_cp->pool_holder();
911 LinkResolver::check_klass_accessibility(holder, k, CHECK);
912 }
913
914
915 u2 ConstantPool::name_ref_index_at(int cp_index) {
916 jint ref_index = name_and_type_at(cp_index);
917 return extract_low_short_from_int(ref_index);
918 }
919
920
921 u2 ConstantPool::signature_ref_index_at(int cp_index) {
922 jint ref_index = name_and_type_at(cp_index);
923 return extract_high_short_from_int(ref_index);
924 }
925
926
927 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
928 return klass_at(klass_ref_index_at(which, code), THREAD);
929 }
930
931 Symbol* ConstantPool::klass_name_at(int cp_index) const {
932 return symbol_at(klass_slot_at(cp_index).name_index());
933 }
934
935 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
936 jint ref_index = klass_ref_index_at(which, code);
937 return klass_at_noresolve(ref_index);
938 }
939
940 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
941 jint ref_index = uncached_klass_ref_index_at(cp_index);
942 return klass_at_noresolve(ref_index);
943 }
944
945 char* ConstantPool::string_at_noresolve(int cp_index) {
946 return unresolved_string_at(cp_index)->as_C_string();
947 }
948
949 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
950 return Signature::basic_type(symbol_at(cp_index));
951 }
952
953
954 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
955 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
956 if (this_cp->tag_at(index).is_string()) {
957 this_cp->string_at(index, CHECK);
958 }
959 }
960 }
961
962 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
963 // Note: caller needs ResourceMark
964
965 // Dig out the detailed message to reuse if possible
966 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
967 if (msg != nullptr) {
968 return msg;
969 }
970
971 Symbol* message = nullptr;
972 // Return specific message for the tag
973 switch (tag.value()) {
974 case JVM_CONSTANT_UnresolvedClass:
975 // return the class name in the error message
976 message = this_cp->klass_name_at(which);
977 break;
978 case JVM_CONSTANT_MethodHandle:
979 // return the method handle name in the error message
980 message = this_cp->method_handle_name_ref_at(which);
981 break;
982 case JVM_CONSTANT_MethodType:
983 // return the method type signature in the error message
984 message = this_cp->method_type_signature_at(which);
985 break;
986 case JVM_CONSTANT_Dynamic:
987 // return the name of the condy in the error message
988 message = this_cp->uncached_name_ref_at(which);
989 break;
990 default:
991 ShouldNotReachHere();
992 }
993
994 return message != nullptr ? message->as_C_string() : nullptr;
995 }
996
997 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
998 constantTag tag, oop pending_exception) {
999
1000 ResourceMark rm(current);
1001 Symbol* error = pending_exception->klass()->name();
1002 oop cause = java_lang_Throwable::cause(pending_exception);
1003
1004 // Also dig out the exception cause, if present.
1005 Symbol* cause_sym = nullptr;
1006 const char* cause_msg = nullptr;
1007 if (cause != nullptr && cause != pending_exception) {
1008 cause_sym = cause->klass()->name();
1009 cause_msg = java_lang_Throwable::message_as_utf8(cause);
1010 }
1011
1012 const char* message = exception_message(this_cp, which, tag, pending_exception);
1013 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1014 }
1015
1016
1017 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1018 ResourceMark rm(THREAD);
1019 const char* message = nullptr;
1020 Symbol* cause = nullptr;
1021 const char* cause_msg = nullptr;
1022 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1023 assert(error != nullptr, "checking");
1024
1025 CLEAR_PENDING_EXCEPTION;
1026 if (message != nullptr) {
1027 if (cause != nullptr) {
1028 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1029 THROW_MSG_CAUSE(error, message, h_cause);
1030 } else {
1031 THROW_MSG(error, message);
1032 }
1033 } else {
1034 if (cause != nullptr) {
1035 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1036 THROW_CAUSE(error, h_cause);
1037 } else {
1038 THROW(error);
1039 }
1040 }
1041 }
1042
1043 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1044 // exception in the resolution error table, so that the same exception is thrown again.
1045 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1046 constantTag tag, TRAPS) {
1047
1048 int error_tag = tag.error_value();
1049
1050 if (!PENDING_EXCEPTION->
1051 is_a(vmClasses::LinkageError_klass())) {
1052 // Just throw the exception and don't prevent these classes from
1053 // being loaded due to virtual machine errors like StackOverflow
1054 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1055 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1056 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1057 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1058 // CAS in the tag. If a thread beat us to registering this error that's fine.
1059 // If another thread resolved the reference, this is a race condition. This
1060 // thread may have had a security manager or something temporary.
1061 // This doesn't deterministically get an error. So why do we save this?
1062 // We save this because jvmti can add classes to the bootclass path after
1063 // this error, so it needs to get the same error if the error is first.
1064 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1065 (jbyte)tag.value(),
1066 (jbyte)error_tag);
1067 if (old_tag != error_tag && old_tag != tag.value()) {
1068 // MethodHandles and MethodType doesn't change to resolved version.
1069 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1070 // Forget the exception and use the resolved class.
1071 CLEAR_PENDING_EXCEPTION;
1072 }
1073 } else {
1074 // some other thread put this in error state
1075 throw_resolution_error(this_cp, cp_index, CHECK);
1076 }
1077 }
1078
1079 constantTag ConstantPool::constant_tag_at(int cp_index) {
1080 constantTag tag = tag_at(cp_index);
1081 if (tag.is_dynamic_constant()) {
1082 BasicType bt = basic_type_for_constant_at(cp_index);
1083 return constantTag(constantTag::type2tag(bt));
1084 }
1085 return tag;
1086 }
1087
1088 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1089 constantTag tag = tag_at(cp_index);
1090 if (tag.is_dynamic_constant() ||
1091 tag.is_dynamic_constant_in_error()) {
1092 // have to look at the signature for this one
1093 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1094 return Signature::basic_type(constant_type);
1095 }
1096 return tag.basic_type();
1097 }
1098
1099 // Called to resolve constants in the constant pool and return an oop.
1100 // Some constant pool entries cache their resolved oop. This is also
1101 // called to create oops from constants to use in arguments for invokedynamic
1102 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1103 int cp_index, int cache_index,
1104 bool* status_return, TRAPS) {
1105 oop result_oop = nullptr;
1106
1107 if (cache_index == _possible_index_sentinel) {
1108 // It is possible that this constant is one which is cached in the objects.
1109 // We'll do a linear search. This should be OK because this usage is rare.
1110 // FIXME: If bootstrap specifiers stress this code, consider putting in
1111 // a reverse index. Binary search over a short array should do it.
1112 assert(cp_index > 0, "valid constant pool index");
1113 cache_index = this_cp->cp_to_object_index(cp_index);
1114 }
1115 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1116 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1117
1118 if (cache_index >= 0) {
1119 result_oop = this_cp->resolved_reference_at(cache_index);
1120 if (result_oop != nullptr) {
1121 if (result_oop == Universe::the_null_sentinel()) {
1122 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1123 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1124 result_oop = nullptr;
1125 }
1126 if (status_return != nullptr) (*status_return) = true;
1127 return result_oop;
1128 // That was easy...
1129 }
1130 cp_index = this_cp->object_to_cp_index(cache_index);
1131 }
1132
1133 jvalue prim_value; // temp used only in a few cases below
1134
1135 constantTag tag = this_cp->tag_at(cp_index);
1136
1137 if (status_return != nullptr) {
1138 // don't trigger resolution if the constant might need it
1139 switch (tag.value()) {
1140 case JVM_CONSTANT_Class:
1141 {
1142 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
1143 int resolved_klass_index = kslot.resolved_klass_index();
1144 if (this_cp->resolved_klasses()->at(resolved_klass_index) == nullptr) {
1145 (*status_return) = false;
1146 return nullptr;
1147 }
1148 // the klass is waiting in the CP; go get it
1149 break;
1150 }
1151 case JVM_CONSTANT_String:
1152 case JVM_CONSTANT_Integer:
1153 case JVM_CONSTANT_Float:
1154 case JVM_CONSTANT_Long:
1155 case JVM_CONSTANT_Double:
1156 // these guys trigger OOM at worst
1157 break;
1158 default:
1159 (*status_return) = false;
1160 return nullptr;
1161 }
1162 // from now on there is either success or an OOME
1163 (*status_return) = true;
1164 }
1165
1166 switch (tag.value()) {
1167
1168 case JVM_CONSTANT_UnresolvedClass:
1169 case JVM_CONSTANT_Class:
1170 {
1171 assert(cache_index == _no_index_sentinel, "should not have been set");
1172 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1173 // ldc wants the java mirror.
1174 result_oop = resolved->java_mirror();
1175 break;
1176 }
1177
1178 case JVM_CONSTANT_Dynamic:
1179 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1180 ClassLoader::perf_resolve_invokedynamic_count());
1181
1182 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1183 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1184
1185 // The initial step in resolving an unresolved symbolic reference to a
1186 // dynamically-computed constant is to resolve the symbolic reference to a
1187 // method handle which will be the bootstrap method for the dynamically-computed
1188 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1189 // method fails, then a MethodHandleInError is stored at the corresponding
1190 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1191 // set a DynamicConstantInError here since any subsequent use of this
1192 // bootstrap method will encounter the resolution of MethodHandleInError.
1193 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1194 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1195 // for the bootstrap_specifier created above.
1196 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1197 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1198 if (HAS_PENDING_EXCEPTION) {
1199 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1200 // will check for a LinkageError and store a DynamicConstantInError.
1201 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1202 }
1203 result_oop = bootstrap_specifier.resolved_value()();
1204 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1205 if (!is_reference_type(type)) {
1206 // Make sure the primitive value is properly boxed.
1207 // This is a JDK responsibility.
1208 const char* fail = nullptr;
1209 if (result_oop == nullptr) {
1210 fail = "null result instead of box";
1211 } else if (!is_java_primitive(type)) {
1212 // FIXME: support value types via unboxing
1213 fail = "can only handle references and primitives";
1214 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1215 fail = "primitive is not properly boxed";
1216 }
1217 if (fail != nullptr) {
1218 // Since this exception is not a LinkageError, throw exception
1219 // but do not save a DynamicInError resolution result.
1220 // See section 5.4.3 of the VM spec.
1221 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1222 }
1223 }
1224
1225 LogTarget(Debug, methodhandles, condy) lt_condy;
1226 if (lt_condy.is_enabled()) {
1227 LogStream ls(lt_condy);
1228 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1229 }
1230 break;
1231 }
1232
1233 case JVM_CONSTANT_String:
1234 assert(cache_index != _no_index_sentinel, "should have been set");
1235 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1236 break;
1237
1238 case JVM_CONSTANT_MethodHandle:
1239 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1240 ClassLoader::perf_resolve_method_handle_count());
1241
1242 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1243 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1244 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1245 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1246 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1247 { ResourceMark rm(THREAD);
1248 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1249 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1250 callee_index, name->as_C_string(), signature->as_C_string());
1251 }
1252
1253 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1254 if (HAS_PENDING_EXCEPTION) {
1255 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1256 }
1257
1258 // Check constant pool method consistency
1259 if ((callee->is_interface() && m_tag.is_method()) ||
1260 (!callee->is_interface() && m_tag.is_interface_method())) {
1261 ResourceMark rm(THREAD);
1262 stringStream ss;
1263 ss.print("Inconsistent constant pool data in classfile for class %s. "
1264 "Method '", callee->name()->as_C_string());
1265 signature->print_as_signature_external_return_type(&ss);
1266 ss.print(" %s(", name->as_C_string());
1267 signature->print_as_signature_external_parameters(&ss);
1268 ss.print(")' at index %d is %s and should be %s",
1269 cp_index,
1270 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1271 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1272 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1273 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1274 }
1275
1276 Klass* klass = this_cp->pool_holder();
1277 HandleMark hm(THREAD);
1278 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1279 callee, name, signature,
1280 THREAD);
1281 if (HAS_PENDING_EXCEPTION) {
1282 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1283 }
1284 result_oop = value();
1285 break;
1286 }
1287
1288 case JVM_CONSTANT_MethodType:
1289 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1290 ClassLoader::perf_resolve_method_type_count());
1291
1292 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1293 { ResourceMark rm(THREAD);
1294 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1295 cp_index, this_cp->method_type_index_at(cp_index),
1296 signature->as_C_string());
1297 }
1298 Klass* klass = this_cp->pool_holder();
1299 HandleMark hm(THREAD);
1300 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1301 result_oop = value();
1302 if (HAS_PENDING_EXCEPTION) {
1303 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1304 }
1305 break;
1306 }
1307
1308 case JVM_CONSTANT_Integer:
1309 assert(cache_index == _no_index_sentinel, "should not have been set");
1310 prim_value.i = this_cp->int_at(cp_index);
1311 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1312 break;
1313
1314 case JVM_CONSTANT_Float:
1315 assert(cache_index == _no_index_sentinel, "should not have been set");
1316 prim_value.f = this_cp->float_at(cp_index);
1317 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1318 break;
1319
1320 case JVM_CONSTANT_Long:
1321 assert(cache_index == _no_index_sentinel, "should not have been set");
1322 prim_value.j = this_cp->long_at(cp_index);
1323 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1324 break;
1325
1326 case JVM_CONSTANT_Double:
1327 assert(cache_index == _no_index_sentinel, "should not have been set");
1328 prim_value.d = this_cp->double_at(cp_index);
1329 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1330 break;
1331
1332 case JVM_CONSTANT_UnresolvedClassInError:
1333 case JVM_CONSTANT_DynamicInError:
1334 case JVM_CONSTANT_MethodHandleInError:
1335 case JVM_CONSTANT_MethodTypeInError:
1336 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1337 break;
1338
1339 default:
1340 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1341 break;
1342 }
1343
1344 if (cache_index >= 0) {
1345 // Benign race condition: resolved_references may already be filled in.
1346 // The important thing here is that all threads pick up the same result.
1347 // It doesn't matter which racing thread wins, as long as only one
1348 // result is used by all threads, and all future queries.
1349 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1350 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1351 if (old_result == nullptr) {
1352 return result_oop; // was installed
1353 } else {
1354 // Return the winning thread's result. This can be different than
1355 // the result here for MethodHandles.
1356 if (old_result == Universe::the_null_sentinel())
1357 old_result = nullptr;
1358 return old_result;
1359 }
1360 } else {
1361 assert(result_oop != Universe::the_null_sentinel(), "");
1362 return result_oop;
1363 }
1364 }
1365
1366 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1367 Symbol* sym = unresolved_string_at(cp_index);
1368 oop str = StringTable::intern(sym, CHECK_(nullptr));
1369 assert(java_lang_String::is_instance(str), "must be string");
1370 return str;
1371 }
1372
1373 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1374 int start_arg, int end_arg,
1375 objArrayHandle info, int pos,
1376 bool must_resolve, Handle if_not_available,
1377 TRAPS) {
1378 int limit = pos + end_arg - start_arg;
1379 // checks: cp_index in range [0..this_cp->length),
1380 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1381 // info array non-null, pos..limit in [0..info.length]
1382 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1383 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1384 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1385 (0 > start_arg || start_arg > end_arg) ||
1386 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1387 (0 > pos || pos > limit) ||
1388 (info.is_null() || limit > info->length())) {
1389 // An index or something else went wrong; throw an error.
1390 // Since this is an internal API, we don't expect this,
1391 // so we don't bother to craft a nice message.
1392 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1393 }
1394 // now we can loop safely
1395 int info_i = pos;
1396 for (int i = start_arg; i < end_arg; i++) {
1397 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1398 oop arg_oop;
1399 if (must_resolve) {
1400 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1401 } else {
1402 bool found_it = false;
1403 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1404 if (!found_it) arg_oop = if_not_available();
1405 }
1406 info->obj_at_put(info_i++, arg_oop);
1407 }
1408 }
1409
1410 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1411 // If the string has already been interned, this entry will be non-null
1412 oop str = this_cp->resolved_reference_at(obj_index);
1413 assert(str != Universe::the_null_sentinel(), "");
1414 if (str != nullptr) return str;
1415 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1416 str = StringTable::intern(sym, CHECK_(nullptr));
1417 this_cp->string_at_put(obj_index, str);
1418 assert(java_lang_String::is_instance(str), "must be string");
1419 return str;
1420 }
1421
1422
1423 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1424 // Names are interned, so we can compare Symbol*s directly
1425 Symbol* cp_name = klass_name_at(cp_index);
1426 return (cp_name == k->name());
1427 }
1428
1429
1430 // Iterate over symbols and decrement ones which are Symbol*s
1431 // This is done during GC.
1432 // Only decrement the UTF8 symbols. Strings point to
1433 // these symbols but didn't increment the reference count.
1434 void ConstantPool::unreference_symbols() {
1435 for (int index = 1; index < length(); index++) { // Index 0 is unused
1436 constantTag tag = tag_at(index);
1437 if (tag.is_symbol()) {
1438 symbol_at(index)->decrement_refcount();
1439 }
1440 }
1441 }
1442
1443
1444 // Compare this constant pool's entry at index1 to the constant pool
1445 // cp2's entry at index2.
1446 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1447 int index2) {
1448
1449 // The error tags are equivalent to non-error tags when comparing
1450 jbyte t1 = tag_at(index1).non_error_value();
1451 jbyte t2 = cp2->tag_at(index2).non_error_value();
1452
1453 // Some classes are pre-resolved (like Throwable) which may lead to
1454 // consider it as a different entry. We then revert them back temporarily
1455 // to ensure proper comparison.
1456 if (t1 == JVM_CONSTANT_Class) {
1457 t1 = JVM_CONSTANT_UnresolvedClass;
1458 }
1459 if (t2 == JVM_CONSTANT_Class) {
1460 t2 = JVM_CONSTANT_UnresolvedClass;
1461 }
1462
1463 if (t1 != t2) {
1464 // Not the same entry type so there is nothing else to check. Note
1465 // that this style of checking will consider resolved/unresolved
1466 // class pairs as different.
1467 // From the ConstantPool* API point of view, this is correct
1468 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1469 // plays out in the context of ConstantPool* merging.
1470 return false;
1471 }
1472
1473 switch (t1) {
1474 case JVM_CONSTANT_ClassIndex:
1475 {
1476 int recur1 = klass_index_at(index1);
1477 int recur2 = cp2->klass_index_at(index2);
1478 if (compare_entry_to(recur1, cp2, recur2)) {
1479 return true;
1480 }
1481 } break;
1482
1483 case JVM_CONSTANT_Double:
1484 {
1485 jdouble d1 = double_at(index1);
1486 jdouble d2 = cp2->double_at(index2);
1487 if (d1 == d2) {
1488 return true;
1489 }
1490 } break;
1491
1492 case JVM_CONSTANT_Fieldref:
1493 case JVM_CONSTANT_InterfaceMethodref:
1494 case JVM_CONSTANT_Methodref:
1495 {
1496 int recur1 = uncached_klass_ref_index_at(index1);
1497 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1498 bool match = compare_entry_to(recur1, cp2, recur2);
1499 if (match) {
1500 recur1 = uncached_name_and_type_ref_index_at(index1);
1501 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1502 if (compare_entry_to(recur1, cp2, recur2)) {
1503 return true;
1504 }
1505 }
1506 } break;
1507
1508 case JVM_CONSTANT_Float:
1509 {
1510 jfloat f1 = float_at(index1);
1511 jfloat f2 = cp2->float_at(index2);
1512 if (f1 == f2) {
1513 return true;
1514 }
1515 } break;
1516
1517 case JVM_CONSTANT_Integer:
1518 {
1519 jint i1 = int_at(index1);
1520 jint i2 = cp2->int_at(index2);
1521 if (i1 == i2) {
1522 return true;
1523 }
1524 } break;
1525
1526 case JVM_CONSTANT_Long:
1527 {
1528 jlong l1 = long_at(index1);
1529 jlong l2 = cp2->long_at(index2);
1530 if (l1 == l2) {
1531 return true;
1532 }
1533 } break;
1534
1535 case JVM_CONSTANT_NameAndType:
1536 {
1537 int recur1 = name_ref_index_at(index1);
1538 int recur2 = cp2->name_ref_index_at(index2);
1539 if (compare_entry_to(recur1, cp2, recur2)) {
1540 recur1 = signature_ref_index_at(index1);
1541 recur2 = cp2->signature_ref_index_at(index2);
1542 if (compare_entry_to(recur1, cp2, recur2)) {
1543 return true;
1544 }
1545 }
1546 } break;
1547
1548 case JVM_CONSTANT_StringIndex:
1549 {
1550 int recur1 = string_index_at(index1);
1551 int recur2 = cp2->string_index_at(index2);
1552 if (compare_entry_to(recur1, cp2, recur2)) {
1553 return true;
1554 }
1555 } break;
1556
1557 case JVM_CONSTANT_UnresolvedClass:
1558 {
1559 Symbol* k1 = klass_name_at(index1);
1560 Symbol* k2 = cp2->klass_name_at(index2);
1561 if (k1 == k2) {
1562 return true;
1563 }
1564 } break;
1565
1566 case JVM_CONSTANT_MethodType:
1567 {
1568 int k1 = method_type_index_at(index1);
1569 int k2 = cp2->method_type_index_at(index2);
1570 if (compare_entry_to(k1, cp2, k2)) {
1571 return true;
1572 }
1573 } break;
1574
1575 case JVM_CONSTANT_MethodHandle:
1576 {
1577 int k1 = method_handle_ref_kind_at(index1);
1578 int k2 = cp2->method_handle_ref_kind_at(index2);
1579 if (k1 == k2) {
1580 int i1 = method_handle_index_at(index1);
1581 int i2 = cp2->method_handle_index_at(index2);
1582 if (compare_entry_to(i1, cp2, i2)) {
1583 return true;
1584 }
1585 }
1586 } break;
1587
1588 case JVM_CONSTANT_Dynamic:
1589 {
1590 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1591 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1592 int i1 = bootstrap_methods_attribute_index(index1);
1593 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1594 bool match_entry = compare_entry_to(k1, cp2, k2);
1595 bool match_operand = compare_operand_to(i1, cp2, i2);
1596 return (match_entry && match_operand);
1597 } break;
1598
1599 case JVM_CONSTANT_InvokeDynamic:
1600 {
1601 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1602 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1603 int i1 = bootstrap_methods_attribute_index(index1);
1604 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1605 bool match_entry = compare_entry_to(k1, cp2, k2);
1606 bool match_operand = compare_operand_to(i1, cp2, i2);
1607 return (match_entry && match_operand);
1608 } break;
1609
1610 case JVM_CONSTANT_String:
1611 {
1612 Symbol* s1 = unresolved_string_at(index1);
1613 Symbol* s2 = cp2->unresolved_string_at(index2);
1614 if (s1 == s2) {
1615 return true;
1616 }
1617 } break;
1618
1619 case JVM_CONSTANT_Utf8:
1620 {
1621 Symbol* s1 = symbol_at(index1);
1622 Symbol* s2 = cp2->symbol_at(index2);
1623 if (s1 == s2) {
1624 return true;
1625 }
1626 } break;
1627
1628 // Invalid is used as the tag for the second constant pool entry
1629 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1630 // not be seen by itself.
1631 case JVM_CONSTANT_Invalid: // fall through
1632
1633 default:
1634 ShouldNotReachHere();
1635 break;
1636 }
1637
1638 return false;
1639 } // end compare_entry_to()
1640
1641
1642 // Resize the operands array with delta_len and delta_size.
1643 // Used in RedefineClasses for CP merge.
1644 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1645 int old_len = operand_array_length(operands());
1646 int new_len = old_len + delta_len;
1647 int min_len = (delta_len > 0) ? old_len : new_len;
1648
1649 int old_size = operands()->length();
1650 int new_size = old_size + delta_size;
1651 int min_size = (delta_size > 0) ? old_size : new_size;
1652
1653 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1654 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1655
1656 // Set index in the resized array for existing elements only
1657 for (int idx = 0; idx < min_len; idx++) {
1658 int offset = operand_offset_at(idx); // offset in original array
1659 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1660 }
1661 // Copy the bootstrap specifiers only
1662 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1663 new_ops->adr_at(2*new_len),
1664 (min_size - 2*min_len) * sizeof(u2));
1665 // Explicitly deallocate old operands array.
1666 // Note, it is not needed for 7u backport.
1667 if ( operands() != nullptr) { // the safety check
1668 MetadataFactory::free_array<u2>(loader_data, operands());
1669 }
1670 set_operands(new_ops);
1671 } // end resize_operands()
1672
1673
1674 // Extend the operands array with the length and size of the ext_cp operands.
1675 // Used in RedefineClasses for CP merge.
1676 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1677 int delta_len = operand_array_length(ext_cp->operands());
1678 if (delta_len == 0) {
1679 return; // nothing to do
1680 }
1681 int delta_size = ext_cp->operands()->length();
1682
1683 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1684
1685 if (operand_array_length(operands()) == 0) {
1686 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1687 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1688 // The first element index defines the offset of second part
1689 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1690 set_operands(new_ops);
1691 } else {
1692 resize_operands(delta_len, delta_size, CHECK);
1693 }
1694
1695 } // end extend_operands()
1696
1697
1698 // Shrink the operands array to a smaller array with new_len length.
1699 // Used in RedefineClasses for CP merge.
1700 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1701 int old_len = operand_array_length(operands());
1702 if (new_len == old_len) {
1703 return; // nothing to do
1704 }
1705 assert(new_len < old_len, "shrunken operands array must be smaller");
1706
1707 int free_base = operand_next_offset_at(new_len - 1);
1708 int delta_len = new_len - old_len;
1709 int delta_size = 2*delta_len + free_base - operands()->length();
1710
1711 resize_operands(delta_len, delta_size, CHECK);
1712
1713 } // end shrink_operands()
1714
1715
1716 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1717 const constantPoolHandle& to_cp,
1718 TRAPS) {
1719
1720 int from_oplen = operand_array_length(from_cp->operands());
1721 int old_oplen = operand_array_length(to_cp->operands());
1722 if (from_oplen != 0) {
1723 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1724 // append my operands to the target's operands array
1725 if (old_oplen == 0) {
1726 // Can't just reuse from_cp's operand list because of deallocation issues
1727 int len = from_cp->operands()->length();
1728 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1729 Copy::conjoint_memory_atomic(
1730 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1731 to_cp->set_operands(new_ops);
1732 } else {
1733 int old_len = to_cp->operands()->length();
1734 int from_len = from_cp->operands()->length();
1735 int old_off = old_oplen * sizeof(u2);
1736 int from_off = from_oplen * sizeof(u2);
1737 // Use the metaspace for the destination constant pool
1738 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1739 int fillp = 0, len = 0;
1740 // first part of dest
1741 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1742 new_operands->adr_at(fillp),
1743 (len = old_off) * sizeof(u2));
1744 fillp += len;
1745 // first part of src
1746 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1747 new_operands->adr_at(fillp),
1748 (len = from_off) * sizeof(u2));
1749 fillp += len;
1750 // second part of dest
1751 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1752 new_operands->adr_at(fillp),
1753 (len = old_len - old_off) * sizeof(u2));
1754 fillp += len;
1755 // second part of src
1756 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1757 new_operands->adr_at(fillp),
1758 (len = from_len - from_off) * sizeof(u2));
1759 fillp += len;
1760 assert(fillp == new_operands->length(), "");
1761
1762 // Adjust indexes in the first part of the copied operands array.
1763 for (int j = 0; j < from_oplen; j++) {
1764 int offset = operand_offset_at(new_operands, old_oplen + j);
1765 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1766 offset += old_len; // every new tuple is preceded by old_len extra u2's
1767 operand_offset_at_put(new_operands, old_oplen + j, offset);
1768 }
1769
1770 // replace target operands array with combined array
1771 to_cp->set_operands(new_operands);
1772 }
1773 }
1774 } // end copy_operands()
1775
1776
1777 // Copy this constant pool's entries at start_i to end_i (inclusive)
1778 // to the constant pool to_cp's entries starting at to_i. A total of
1779 // (end_i - start_i) + 1 entries are copied.
1780 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1781 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1782
1783
1784 int dest_cpi = to_i; // leave original alone for debug purposes
1785
1786 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1787 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1788
1789 switch (from_cp->tag_at(src_cpi).value()) {
1790 case JVM_CONSTANT_Double:
1791 case JVM_CONSTANT_Long:
1792 // double and long take two constant pool entries
1793 src_cpi += 2;
1794 dest_cpi += 2;
1795 break;
1796
1797 default:
1798 // all others take one constant pool entry
1799 src_cpi++;
1800 dest_cpi++;
1801 break;
1802 }
1803 }
1804 copy_operands(from_cp, to_cp, CHECK);
1805
1806 } // end copy_cp_to_impl()
1807
1808
1809 // Copy this constant pool's entry at from_i to the constant pool
1810 // to_cp's entry at to_i.
1811 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1812 const constantPoolHandle& to_cp, int to_i) {
1813
1814 int tag = from_cp->tag_at(from_i).value();
1815 switch (tag) {
1816 case JVM_CONSTANT_ClassIndex:
1817 {
1818 jint ki = from_cp->klass_index_at(from_i);
1819 to_cp->klass_index_at_put(to_i, ki);
1820 } break;
1821
1822 case JVM_CONSTANT_Double:
1823 {
1824 jdouble d = from_cp->double_at(from_i);
1825 to_cp->double_at_put(to_i, d);
1826 // double takes two constant pool entries so init second entry's tag
1827 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1828 } break;
1829
1830 case JVM_CONSTANT_Fieldref:
1831 {
1832 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1833 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1834 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1835 } break;
1836
1837 case JVM_CONSTANT_Float:
1838 {
1839 jfloat f = from_cp->float_at(from_i);
1840 to_cp->float_at_put(to_i, f);
1841 } break;
1842
1843 case JVM_CONSTANT_Integer:
1844 {
1845 jint i = from_cp->int_at(from_i);
1846 to_cp->int_at_put(to_i, i);
1847 } break;
1848
1849 case JVM_CONSTANT_InterfaceMethodref:
1850 {
1851 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1852 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1853 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1854 } break;
1855
1856 case JVM_CONSTANT_Long:
1857 {
1858 jlong l = from_cp->long_at(from_i);
1859 to_cp->long_at_put(to_i, l);
1860 // long takes two constant pool entries so init second entry's tag
1861 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1862 } break;
1863
1864 case JVM_CONSTANT_Methodref:
1865 {
1866 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1867 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1868 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1869 } break;
1870
1871 case JVM_CONSTANT_NameAndType:
1872 {
1873 int name_ref_index = from_cp->name_ref_index_at(from_i);
1874 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1875 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1876 } break;
1877
1878 case JVM_CONSTANT_StringIndex:
1879 {
1880 jint si = from_cp->string_index_at(from_i);
1881 to_cp->string_index_at_put(to_i, si);
1882 } break;
1883
1884 case JVM_CONSTANT_Class:
1885 case JVM_CONSTANT_UnresolvedClass:
1886 case JVM_CONSTANT_UnresolvedClassInError:
1887 {
1888 // Revert to JVM_CONSTANT_ClassIndex
1889 int name_index = from_cp->klass_slot_at(from_i).name_index();
1890 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1891 to_cp->klass_index_at_put(to_i, name_index);
1892 } break;
1893
1894 case JVM_CONSTANT_String:
1895 {
1896 Symbol* s = from_cp->unresolved_string_at(from_i);
1897 to_cp->unresolved_string_at_put(to_i, s);
1898 } break;
1899
1900 case JVM_CONSTANT_Utf8:
1901 {
1902 Symbol* s = from_cp->symbol_at(from_i);
1903 // Need to increase refcount, the old one will be thrown away and deferenced
1904 s->increment_refcount();
1905 to_cp->symbol_at_put(to_i, s);
1906 } break;
1907
1908 case JVM_CONSTANT_MethodType:
1909 case JVM_CONSTANT_MethodTypeInError:
1910 {
1911 jint k = from_cp->method_type_index_at(from_i);
1912 to_cp->method_type_index_at_put(to_i, k);
1913 } break;
1914
1915 case JVM_CONSTANT_MethodHandle:
1916 case JVM_CONSTANT_MethodHandleInError:
1917 {
1918 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1919 int k2 = from_cp->method_handle_index_at(from_i);
1920 to_cp->method_handle_index_at_put(to_i, k1, k2);
1921 } break;
1922
1923 case JVM_CONSTANT_Dynamic:
1924 case JVM_CONSTANT_DynamicInError:
1925 {
1926 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1927 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1928 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1929 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1930 } break;
1931
1932 case JVM_CONSTANT_InvokeDynamic:
1933 {
1934 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1935 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1936 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1937 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1938 } break;
1939
1940 // Invalid is used as the tag for the second constant pool entry
1941 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1942 // not be seen by itself.
1943 case JVM_CONSTANT_Invalid: // fall through
1944
1945 default:
1946 {
1947 ShouldNotReachHere();
1948 } break;
1949 }
1950 } // end copy_entry_to()
1951
1952 // Search constant pool search_cp for an entry that matches this
1953 // constant pool's entry at pattern_i. Returns the index of a
1954 // matching entry or zero (0) if there is no matching entry.
1955 int ConstantPool::find_matching_entry(int pattern_i,
1956 const constantPoolHandle& search_cp) {
1957
1958 // index zero (0) is not used
1959 for (int i = 1; i < search_cp->length(); i++) {
1960 bool found = compare_entry_to(pattern_i, search_cp, i);
1961 if (found) {
1962 return i;
1963 }
1964 }
1965
1966 return 0; // entry not found; return unused index zero (0)
1967 } // end find_matching_entry()
1968
1969
1970 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1971 // cp2's bootstrap specifier at idx2.
1972 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2) {
1973 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1974 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1975 bool match = compare_entry_to(k1, cp2, k2);
1976
1977 if (!match) {
1978 return false;
1979 }
1980 int argc = operand_argument_count_at(idx1);
1981 if (argc == cp2->operand_argument_count_at(idx2)) {
1982 for (int j = 0; j < argc; j++) {
1983 k1 = operand_argument_index_at(idx1, j);
1984 k2 = cp2->operand_argument_index_at(idx2, j);
1985 match = compare_entry_to(k1, cp2, k2);
1986 if (!match) {
1987 return false;
1988 }
1989 }
1990 return true; // got through loop; all elements equal
1991 }
1992 return false;
1993 } // end compare_operand_to()
1994
1995 // Search constant pool search_cp for a bootstrap specifier that matches
1996 // this constant pool's bootstrap specifier data at pattern_i index.
1997 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
1998 int ConstantPool::find_matching_operand(int pattern_i,
1999 const constantPoolHandle& search_cp, int search_len) {
2000 for (int i = 0; i < search_len; i++) {
2001 bool found = compare_operand_to(pattern_i, search_cp, i);
2002 if (found) {
2003 return i;
2004 }
2005 }
2006 return -1; // bootstrap specifier data not found; return unused index (-1)
2007 } // end find_matching_operand()
2008
2009
2010 #ifndef PRODUCT
2011
2012 const char* ConstantPool::printable_name_at(int cp_index) {
2013
2014 constantTag tag = tag_at(cp_index);
2015
2016 if (tag.is_string()) {
2017 return string_at_noresolve(cp_index);
2018 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
2019 return klass_name_at(cp_index)->as_C_string();
2020 } else if (tag.is_symbol()) {
2021 return symbol_at(cp_index)->as_C_string();
2022 }
2023 return "";
2024 }
2025
2026 #endif // PRODUCT
2027
2028
2029 // JVMTI GetConstantPool support
2030
2031 // For debugging of constant pool
2032 const bool debug_cpool = false;
2033
2034 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
2035
2036 static void print_cpool_bytes(jint cnt, u1 *bytes) {
2037 const char* WARN_MSG = "Must not be such entry!";
2038 jint size = 0;
2039 u2 idx1, idx2;
2040
2041 for (jint idx = 1; idx < cnt; idx++) {
2042 jint ent_size = 0;
2043 u1 tag = *bytes++;
2044 size++; // count tag
2045
2046 printf("const #%03d, tag: %02d ", idx, tag);
2047 switch(tag) {
2048 case JVM_CONSTANT_Invalid: {
2049 printf("Invalid");
2050 break;
2051 }
2052 case JVM_CONSTANT_Unicode: {
2053 printf("Unicode %s", WARN_MSG);
2054 break;
2055 }
2056 case JVM_CONSTANT_Utf8: {
2057 u2 len = Bytes::get_Java_u2(bytes);
2058 char str[128];
2059 if (len > 127) {
2060 len = 127;
2061 }
2062 strncpy(str, (char *) (bytes+2), len);
2063 str[len] = '\0';
2064 printf("Utf8 \"%s\"", str);
2065 ent_size = 2 + len;
2066 break;
2067 }
2068 case JVM_CONSTANT_Integer: {
2069 u4 val = Bytes::get_Java_u4(bytes);
2070 printf("int %d", *(int *) &val);
2071 ent_size = 4;
2072 break;
2073 }
2074 case JVM_CONSTANT_Float: {
2075 u4 val = Bytes::get_Java_u4(bytes);
2076 printf("float %5.3ff", *(float *) &val);
2077 ent_size = 4;
2078 break;
2079 }
2080 case JVM_CONSTANT_Long: {
2081 u8 val = Bytes::get_Java_u8(bytes);
2082 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
2083 ent_size = 8;
2084 idx++; // Long takes two cpool slots
2085 break;
2086 }
2087 case JVM_CONSTANT_Double: {
2088 u8 val = Bytes::get_Java_u8(bytes);
2089 printf("double %5.3fd", *(jdouble *)&val);
2090 ent_size = 8;
2091 idx++; // Double takes two cpool slots
2092 break;
2093 }
2094 case JVM_CONSTANT_Class: {
2095 idx1 = Bytes::get_Java_u2(bytes);
2096 printf("class #%03d", idx1);
2097 ent_size = 2;
2098 break;
2099 }
2100 case JVM_CONSTANT_String: {
2101 idx1 = Bytes::get_Java_u2(bytes);
2102 printf("String #%03d", idx1);
2103 ent_size = 2;
2104 break;
2105 }
2106 case JVM_CONSTANT_Fieldref: {
2107 idx1 = Bytes::get_Java_u2(bytes);
2108 idx2 = Bytes::get_Java_u2(bytes+2);
2109 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
2110 ent_size = 4;
2111 break;
2112 }
2113 case JVM_CONSTANT_Methodref: {
2114 idx1 = Bytes::get_Java_u2(bytes);
2115 idx2 = Bytes::get_Java_u2(bytes+2);
2116 printf("Method #%03d, #%03d", idx1, idx2);
2117 ent_size = 4;
2118 break;
2119 }
2120 case JVM_CONSTANT_InterfaceMethodref: {
2121 idx1 = Bytes::get_Java_u2(bytes);
2122 idx2 = Bytes::get_Java_u2(bytes+2);
2123 printf("InterfMethod #%03d, #%03d", idx1, idx2);
2124 ent_size = 4;
2125 break;
2126 }
2127 case JVM_CONSTANT_NameAndType: {
2128 idx1 = Bytes::get_Java_u2(bytes);
2129 idx2 = Bytes::get_Java_u2(bytes+2);
2130 printf("NameAndType #%03d, #%03d", idx1, idx2);
2131 ent_size = 4;
2132 break;
2133 }
2134 case JVM_CONSTANT_ClassIndex: {
2135 printf("ClassIndex %s", WARN_MSG);
2136 break;
2137 }
2138 case JVM_CONSTANT_UnresolvedClass: {
2139 printf("UnresolvedClass: %s", WARN_MSG);
2140 break;
2141 }
2142 case JVM_CONSTANT_UnresolvedClassInError: {
2143 printf("UnresolvedClassInErr: %s", WARN_MSG);
2144 break;
2145 }
2146 case JVM_CONSTANT_StringIndex: {
2147 printf("StringIndex: %s", WARN_MSG);
2148 break;
2149 }
2150 }
2151 printf(";\n");
2152 bytes += ent_size;
2153 size += ent_size;
2154 }
2155 printf("Cpool size: %d\n", size);
2156 fflush(nullptr);
2157 return;
2158 } /* end print_cpool_bytes */
2159
2160
2161 // Returns size of constant pool entry.
2162 jint ConstantPool::cpool_entry_size(jint idx) {
2163 switch(tag_at(idx).value()) {
2164 case JVM_CONSTANT_Invalid:
2165 case JVM_CONSTANT_Unicode:
2166 return 1;
2167
2168 case JVM_CONSTANT_Utf8:
2169 return 3 + symbol_at(idx)->utf8_length();
2170
2171 case JVM_CONSTANT_Class:
2172 case JVM_CONSTANT_String:
2173 case JVM_CONSTANT_ClassIndex:
2174 case JVM_CONSTANT_UnresolvedClass:
2175 case JVM_CONSTANT_UnresolvedClassInError:
2176 case JVM_CONSTANT_StringIndex:
2177 case JVM_CONSTANT_MethodType:
2178 case JVM_CONSTANT_MethodTypeInError:
2179 return 3;
2180
2181 case JVM_CONSTANT_MethodHandle:
2182 case JVM_CONSTANT_MethodHandleInError:
2183 return 4; //tag, ref_kind, ref_index
2184
2185 case JVM_CONSTANT_Integer:
2186 case JVM_CONSTANT_Float:
2187 case JVM_CONSTANT_Fieldref:
2188 case JVM_CONSTANT_Methodref:
2189 case JVM_CONSTANT_InterfaceMethodref:
2190 case JVM_CONSTANT_NameAndType:
2191 return 5;
2192
2193 case JVM_CONSTANT_Dynamic:
2194 case JVM_CONSTANT_DynamicInError:
2195 case JVM_CONSTANT_InvokeDynamic:
2196 // u1 tag, u2 bsm, u2 nt
2197 return 5;
2198
2199 case JVM_CONSTANT_Long:
2200 case JVM_CONSTANT_Double:
2201 return 9;
2202 }
2203 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2204 return 1;
2205 } /* end cpool_entry_size */
2206
2207
2208 // SymbolHash is used to find a constant pool index from a string.
2209 // This function fills in SymbolHashs, one for utf8s and one for
2210 // class names, returns size of the cpool raw bytes.
2211 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
2212 SymbolHash *classmap) {
2213 jint size = 0;
2214
2215 for (u2 idx = 1; idx < length(); idx++) {
2216 u2 tag = tag_at(idx).value();
2217 size += cpool_entry_size(idx);
2218
2219 switch(tag) {
2220 case JVM_CONSTANT_Utf8: {
2221 Symbol* sym = symbol_at(idx);
2222 symmap->add_if_absent(sym, idx);
2223 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
2224 break;
2225 }
2226 case JVM_CONSTANT_Class:
2227 case JVM_CONSTANT_UnresolvedClass:
2228 case JVM_CONSTANT_UnresolvedClassInError: {
2229 Symbol* sym = klass_name_at(idx);
2230 classmap->add_if_absent(sym, idx);
2231 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
2232 break;
2233 }
2234 case JVM_CONSTANT_Long:
2235 case JVM_CONSTANT_Double: {
2236 idx++; // Both Long and Double take two cpool slots
2237 break;
2238 }
2239 }
2240 }
2241 return size;
2242 } /* end hash_utf8_entries_to */
2243
2244
2245 // Copy cpool bytes.
2246 // Returns:
2247 // 0, in case of OutOfMemoryError
2248 // -1, in case of internal error
2249 // > 0, count of the raw cpool bytes that have been copied
2250 int ConstantPool::copy_cpool_bytes(int cpool_size,
2251 SymbolHash* tbl,
2252 unsigned char *bytes) {
2253 u2 idx1, idx2;
2254 jint size = 0;
2255 jint cnt = length();
2256 unsigned char *start_bytes = bytes;
2257
2258 for (jint idx = 1; idx < cnt; idx++) {
2259 u1 tag = tag_at(idx).value();
2260 jint ent_size = cpool_entry_size(idx);
2261
2262 assert(size + ent_size <= cpool_size, "Size mismatch");
2263
2264 *bytes = tag;
2265 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
2266 switch(tag) {
2267 case JVM_CONSTANT_Invalid: {
2268 DBG(printf("JVM_CONSTANT_Invalid"));
2269 break;
2270 }
2271 case JVM_CONSTANT_Unicode: {
2272 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2273 DBG(printf("JVM_CONSTANT_Unicode"));
2274 break;
2275 }
2276 case JVM_CONSTANT_Utf8: {
2277 Symbol* sym = symbol_at(idx);
2278 char* str = sym->as_utf8();
2279 // Warning! It's crashing on x86 with len = sym->utf8_length()
2280 int len = (int) strlen(str);
2281 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2282 for (int i = 0; i < len; i++) {
2283 bytes[3+i] = (u1) str[i];
2284 }
2285 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
2286 break;
2287 }
2288 case JVM_CONSTANT_Integer: {
2289 jint val = int_at(idx);
2290 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2291 break;
2292 }
2293 case JVM_CONSTANT_Float: {
2294 jfloat val = float_at(idx);
2295 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2296 break;
2297 }
2298 case JVM_CONSTANT_Long: {
2299 jlong val = long_at(idx);
2300 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2301 idx++; // Long takes two cpool slots
2302 break;
2303 }
2304 case JVM_CONSTANT_Double: {
2305 jdouble val = double_at(idx);
2306 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2307 idx++; // Double takes two cpool slots
2308 break;
2309 }
2310 case JVM_CONSTANT_Class:
2311 case JVM_CONSTANT_UnresolvedClass:
2312 case JVM_CONSTANT_UnresolvedClassInError: {
2313 *bytes = JVM_CONSTANT_Class;
2314 Symbol* sym = klass_name_at(idx);
2315 idx1 = tbl->symbol_to_value(sym);
2316 assert(idx1 != 0, "Have not found a hashtable entry");
2317 Bytes::put_Java_u2((address) (bytes+1), idx1);
2318 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
2319 break;
2320 }
2321 case JVM_CONSTANT_String: {
2322 *bytes = JVM_CONSTANT_String;
2323 Symbol* sym = unresolved_string_at(idx);
2324 idx1 = tbl->symbol_to_value(sym);
2325 assert(idx1 != 0, "Have not found a hashtable entry");
2326 Bytes::put_Java_u2((address) (bytes+1), idx1);
2327 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
2328 break;
2329 }
2330 case JVM_CONSTANT_Fieldref:
2331 case JVM_CONSTANT_Methodref:
2332 case JVM_CONSTANT_InterfaceMethodref: {
2333 idx1 = uncached_klass_ref_index_at(idx);
2334 idx2 = uncached_name_and_type_ref_index_at(idx);
2335 Bytes::put_Java_u2((address) (bytes+1), idx1);
2336 Bytes::put_Java_u2((address) (bytes+3), idx2);
2337 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
2338 break;
2339 }
2340 case JVM_CONSTANT_NameAndType: {
2341 idx1 = name_ref_index_at(idx);
2342 idx2 = signature_ref_index_at(idx);
2343 Bytes::put_Java_u2((address) (bytes+1), idx1);
2344 Bytes::put_Java_u2((address) (bytes+3), idx2);
2345 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
2346 break;
2347 }
2348 case JVM_CONSTANT_ClassIndex: {
2349 *bytes = JVM_CONSTANT_Class;
2350 idx1 = checked_cast<u2>(klass_index_at(idx));
2351 Bytes::put_Java_u2((address) (bytes+1), idx1);
2352 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
2353 break;
2354 }
2355 case JVM_CONSTANT_StringIndex: {
2356 *bytes = JVM_CONSTANT_String;
2357 idx1 = checked_cast<u2>(string_index_at(idx));
2358 Bytes::put_Java_u2((address) (bytes+1), idx1);
2359 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
2360 break;
2361 }
2362 case JVM_CONSTANT_MethodHandle:
2363 case JVM_CONSTANT_MethodHandleInError: {
2364 *bytes = JVM_CONSTANT_MethodHandle;
2365 int kind = method_handle_ref_kind_at(idx);
2366 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2367 *(bytes+1) = (unsigned char) kind;
2368 Bytes::put_Java_u2((address) (bytes+2), idx1);
2369 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
2370 break;
2371 }
2372 case JVM_CONSTANT_MethodType:
2373 case JVM_CONSTANT_MethodTypeInError: {
2374 *bytes = JVM_CONSTANT_MethodType;
2375 idx1 = checked_cast<u2>(method_type_index_at(idx));
2376 Bytes::put_Java_u2((address) (bytes+1), idx1);
2377 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
2378 break;
2379 }
2380 case JVM_CONSTANT_Dynamic:
2381 case JVM_CONSTANT_DynamicInError: {
2382 *bytes = tag;
2383 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2384 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2385 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2386 Bytes::put_Java_u2((address) (bytes+1), idx1);
2387 Bytes::put_Java_u2((address) (bytes+3), idx2);
2388 DBG(printf("JVM_CONSTANT_Dynamic: %hd %hd", idx1, idx2));
2389 break;
2390 }
2391 case JVM_CONSTANT_InvokeDynamic: {
2392 *bytes = tag;
2393 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2394 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2395 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2396 Bytes::put_Java_u2((address) (bytes+1), idx1);
2397 Bytes::put_Java_u2((address) (bytes+3), idx2);
2398 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
2399 break;
2400 }
2401 }
2402 DBG(printf("\n"));
2403 bytes += ent_size;
2404 size += ent_size;
2405 }
2406 assert(size == cpool_size, "Size mismatch");
2407
2408 // Keep temporarily for debugging until it's stable.
2409 DBG(print_cpool_bytes(cnt, start_bytes));
2410 return (int)(bytes - start_bytes);
2411 } /* end copy_cpool_bytes */
2412
2413 #undef DBG
2414
2415 bool ConstantPool::is_maybe_on_stack() const {
2416 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2417 if (!Continuations::enabled()) {
2418 return false;
2419 }
2420
2421 // If the condition below is true, it means that the nmethod was found to
2422 // be alive the previous completed marking cycle.
2423 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2424 }
2425
2426 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2427 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2428 // memory for the method is reclaimed.
2429 bool ConstantPool::on_stack() const {
2430 if ((_flags &_on_stack) != 0) {
2431 return true;
2432 }
2433
2434 if (_cache == nullptr) {
2435 return false;
2436 }
2437
2438 return is_maybe_on_stack();
2439 }
2440
2441 void ConstantPool::set_on_stack(const bool value) {
2442 if (value) {
2443 // Only record if it's not already set.
2444 if (!on_stack()) {
2445 assert(!is_shared(), "should always be set for shared constant pools");
2446 _flags |= _on_stack;
2447 MetadataOnStackMark::record(this);
2448 }
2449 } else {
2450 // Clearing is done single-threadedly.
2451 if (!is_shared()) {
2452 _flags &= (u2)(~_on_stack);
2453 }
2454 }
2455 }
2456
2457 // Printing
2458
2459 void ConstantPool::print_on(outputStream* st) const {
2460 assert(is_constantPool(), "must be constantPool");
2461 st->print_cr("%s", internal_name());
2462 if (flags() != 0) {
2463 st->print(" - flags: 0x%x", flags());
2464 if (has_preresolution()) st->print(" has_preresolution");
2465 if (on_stack()) st->print(" on_stack");
2466 st->cr();
2467 }
2468 if (pool_holder() != nullptr) {
2469 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2470 }
2471 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2472 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2473 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2474 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2475 st->print_cr(" - cp length: %d", length());
2476
2477 for (int index = 1; index < length(); index++) { // Index 0 is unused
2478 ((ConstantPool*)this)->print_entry_on(index, st);
2479 switch (tag_at(index).value()) {
2480 case JVM_CONSTANT_Long :
2481 case JVM_CONSTANT_Double :
2482 index++; // Skip entry following eigth-byte constant
2483 }
2484
2485 }
2486 st->cr();
2487 }
2488
2489 // Print one constant pool entry
2490 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2491 EXCEPTION_MARK;
2492 st->print(" - %3d : ", cp_index);
2493 tag_at(cp_index).print_on(st);
2494 st->print(" : ");
2495 switch (tag_at(cp_index).value()) {
2496 case JVM_CONSTANT_Class :
2497 { Klass* k = klass_at(cp_index, CATCH);
2498 guarantee(k != nullptr, "need klass");
2499 k->print_value_on(st);
2500 st->print(" {" PTR_FORMAT "}", p2i(k));
2501 }
2502 break;
2503 case JVM_CONSTANT_Fieldref :
2504 case JVM_CONSTANT_Methodref :
2505 case JVM_CONSTANT_InterfaceMethodref :
2506 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2507 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2508 break;
2509 case JVM_CONSTANT_String :
2510 unresolved_string_at(cp_index)->print_value_on(st);
2511 break;
2512 case JVM_CONSTANT_Integer :
2513 st->print("%d", int_at(cp_index));
2514 break;
2515 case JVM_CONSTANT_Float :
2516 st->print("%f", float_at(cp_index));
2517 break;
2518 case JVM_CONSTANT_Long :
2519 st->print_jlong(long_at(cp_index));
2520 break;
2521 case JVM_CONSTANT_Double :
2522 st->print("%lf", double_at(cp_index));
2523 break;
2524 case JVM_CONSTANT_NameAndType :
2525 st->print("name_index=%d", name_ref_index_at(cp_index));
2526 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2527 break;
2528 case JVM_CONSTANT_Utf8 :
2529 symbol_at(cp_index)->print_value_on(st);
2530 break;
2531 case JVM_CONSTANT_ClassIndex: {
2532 int name_index = *int_at_addr(cp_index);
2533 st->print("klass_index=%d ", name_index);
2534 symbol_at(name_index)->print_value_on(st);
2535 }
2536 break;
2537 case JVM_CONSTANT_UnresolvedClass : // fall-through
2538 case JVM_CONSTANT_UnresolvedClassInError: {
2539 CPKlassSlot kslot = klass_slot_at(cp_index);
2540 int resolved_klass_index = kslot.resolved_klass_index();
2541 int name_index = kslot.name_index();
2542 assert(tag_at(name_index).is_symbol(), "sanity");
2543 symbol_at(name_index)->print_value_on(st);
2544 }
2545 break;
2546 case JVM_CONSTANT_MethodHandle :
2547 case JVM_CONSTANT_MethodHandleInError :
2548 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2549 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2550 break;
2551 case JVM_CONSTANT_MethodType :
2552 case JVM_CONSTANT_MethodTypeInError :
2553 st->print("signature_index=%d", method_type_index_at(cp_index));
2554 break;
2555 case JVM_CONSTANT_Dynamic :
2556 case JVM_CONSTANT_DynamicInError :
2557 {
2558 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2559 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2560 int argc = bootstrap_argument_count_at(cp_index);
2561 if (argc > 0) {
2562 for (int arg_i = 0; arg_i < argc; arg_i++) {
2563 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2564 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2565 }
2566 st->print("}");
2567 }
2568 }
2569 break;
2570 case JVM_CONSTANT_InvokeDynamic :
2571 {
2572 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2573 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2574 int argc = bootstrap_argument_count_at(cp_index);
2575 if (argc > 0) {
2576 for (int arg_i = 0; arg_i < argc; arg_i++) {
2577 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2578 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2579 }
2580 st->print("}");
2581 }
2582 }
2583 break;
2584 default:
2585 ShouldNotReachHere();
2586 break;
2587 }
2588 st->cr();
2589 }
2590
2591 void ConstantPool::print_value_on(outputStream* st) const {
2592 assert(is_constantPool(), "must be constantPool");
2593 st->print("constant pool [%d]", length());
2594 if (has_preresolution()) st->print("/preresolution");
2595 if (operands() != nullptr) st->print("/operands[%d]", operands()->length());
2596 print_address_on(st);
2597 if (pool_holder() != nullptr) {
2598 st->print(" for ");
2599 pool_holder()->print_value_on(st);
2600 bool extra = (pool_holder()->constants() != this);
2601 if (extra) st->print(" (extra)");
2602 }
2603 if (cache() != nullptr) {
2604 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2605 }
2606 }
2607
2608 // Verification
2609
2610 void ConstantPool::verify_on(outputStream* st) {
2611 guarantee(is_constantPool(), "object must be constant pool");
2612 for (int i = 0; i< length(); i++) {
2613 constantTag tag = tag_at(i);
2614 if (tag.is_klass() || tag.is_unresolved_klass()) {
2615 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2616 } else if (tag.is_symbol()) {
2617 Symbol* entry = symbol_at(i);
2618 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2619 } else if (tag.is_string()) {
2620 Symbol* entry = unresolved_string_at(i);
2621 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2622 }
2623 }
2624 if (pool_holder() != nullptr) {
2625 // Note: pool_holder() can be null in temporary constant pools
2626 // used during constant pool merging
2627 guarantee(pool_holder()->is_klass(), "should be klass");
2628 }
2629 }