1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotConstantPoolResolver.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/archiveHeapLoader.hpp"
28 #include "cds/archiveHeapWriter.hpp"
29 #include "cds/cdsConfig.hpp"
30 #include "cds/heapShared.hpp"
31 #include "classfile/classLoader.hpp"
32 #include "classfile/classLoaderData.hpp"
33 #include "classfile/javaClasses.inline.hpp"
34 #include "classfile/metadataOnStackMark.hpp"
35 #include "classfile/stringTable.hpp"
36 #include "classfile/systemDictionary.hpp"
37 #include "classfile/systemDictionaryShared.hpp"
38 #include "classfile/vmClasses.hpp"
39 #include "classfile/vmSymbols.hpp"
40 #include "code/codeCache.hpp"
41 #include "interpreter/bootstrapInfo.hpp"
42 #include "interpreter/linkResolver.hpp"
43 #include "jvm.h"
44 #include "logging/log.hpp"
45 #include "logging/logStream.hpp"
46 #include "memory/allocation.inline.hpp"
47 #include "memory/metadataFactory.hpp"
48 #include "memory/metaspaceClosure.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/array.hpp"
53 #include "oops/constantPool.inline.hpp"
54 #include "oops/cpCache.inline.hpp"
55 #include "oops/fieldStreams.inline.hpp"
56 #include "oops/flatArrayKlass.hpp"
57 #include "oops/instanceKlass.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/objArrayKlass.hpp"
60 #include "oops/objArrayOop.inline.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/refArrayOop.hpp"
63 #include "oops/typeArrayOop.inline.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "runtime/atomic.hpp"
66 #include "runtime/fieldDescriptor.inline.hpp"
67 #include "runtime/handles.inline.hpp"
68 #include "runtime/init.hpp"
69 #include "runtime/javaCalls.hpp"
70 #include "runtime/javaThread.inline.hpp"
71 #include "runtime/perfData.hpp"
72 #include "runtime/signature.hpp"
73 #include "runtime/vframe.inline.hpp"
74 #include "utilities/checkedCast.hpp"
75 #include "utilities/copy.hpp"
76
77 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
78 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
79 int size = ConstantPool::size(length);
80 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
81 }
82
83 void ConstantPool::copy_fields(const ConstantPool* orig) {
84 // Preserve dynamic constant information from the original pool
85 if (orig->has_dynamic_constant()) {
86 set_has_dynamic_constant();
87 }
88
89 set_major_version(orig->major_version());
90 set_minor_version(orig->minor_version());
91
92 set_source_file_name_index(orig->source_file_name_index());
93 set_generic_signature_index(orig->generic_signature_index());
94 }
95
96 #ifdef ASSERT
97
98 // MetaspaceObj allocation invariant is calloc equivalent memory
99 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
100 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
101 assert(tags != nullptr, "invariant");
102 const int length = tags->length();
103 for (int index = 0; index < length; ++index) {
104 if (JVM_CONSTANT_Invalid != tags->at(index)) {
105 return false;
106 }
107 }
108 return true;
109 }
110
111 #endif
112
113 ConstantPool::ConstantPool() {
114 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS");
115 }
116
117 ConstantPool::ConstantPool(Array<u1>* tags) :
118 _tags(tags),
119 _length(tags->length()) {
120
121 assert(_tags != nullptr, "invariant");
122 assert(tags->length() == _length, "invariant");
123 assert(tag_array_is_zero_initialized(tags), "invariant");
124 assert(0 == flags(), "invariant");
125 assert(0 == version(), "invariant");
126 assert(nullptr == _pool_holder, "invariant");
127 }
128
129 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
130 if (cache() != nullptr) {
131 MetadataFactory::free_metadata(loader_data, cache());
132 set_cache(nullptr);
133 }
134
135 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
136 set_resolved_klasses(nullptr);
137
138 MetadataFactory::free_array<jushort>(loader_data, operands());
139 set_operands(nullptr);
140
141 release_C_heap_structures();
142
143 // free tag array
144 MetadataFactory::free_array<u1>(loader_data, tags());
145 set_tags(nullptr);
146 }
147
148 void ConstantPool::release_C_heap_structures() {
149 // walk constant pool and decrement symbol reference counts
150 unreference_symbols();
151 }
152
153 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
154 log_trace(aot)("Iter(ConstantPool): %p", this);
155
156 it->push(&_tags, MetaspaceClosure::_writable);
157 it->push(&_cache);
158 it->push(&_pool_holder);
159 it->push(&_operands);
160 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
161
162 for (int i = 0; i < length(); i++) {
163 // The only MSO's embedded in the CP entries are Symbols:
164 // JVM_CONSTANT_String
165 // JVM_CONSTANT_Utf8
166 constantTag ctag = tag_at(i);
167 if (ctag.is_string() || ctag.is_utf8()) {
168 it->push(symbol_at_addr(i));
169 }
170 }
171 }
172
173 objArrayOop ConstantPool::resolved_references() const {
174 return _cache->resolved_references();
175 }
176
177 // Called from outside constant pool resolution where a resolved_reference array
178 // may not be present.
179 objArrayOop ConstantPool::resolved_references_or_null() const {
180 if (_cache == nullptr) {
181 return nullptr;
182 } else {
183 return _cache->resolved_references();
184 }
185 }
186
187 oop ConstantPool::resolved_reference_at(int index) const {
188 oop result = resolved_references()->obj_at(index);
189 assert(oopDesc::is_oop_or_null(result), "Must be oop");
190 return result;
191 }
192
193 // Use a CAS for multithreaded access
194 oop ConstantPool::set_resolved_reference_at(int index, oop new_result) {
195 assert(oopDesc::is_oop_or_null(new_result), "Must be oop");
196 return refArrayOopDesc::cast(resolved_references())->replace_if_null(index, new_result);
197 }
198
199 // Create resolved_references array and mapping array for original cp indexes
200 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
201 // to map it back for resolving and some unlikely miscellaneous uses.
202 // The objects created by invokedynamic are appended to this list.
203 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
204 const intStack& reference_map,
205 int constant_pool_map_length,
206 TRAPS) {
207 // Initialized the resolved object cache.
208 int map_length = reference_map.length();
209 if (map_length > 0) {
210 // Only need mapping back to constant pool entries. The map isn't used for
211 // invokedynamic resolved_reference entries. For invokedynamic entries,
212 // the constant pool cache index has the mapping back to both the constant
213 // pool and to the resolved reference index.
214 if (constant_pool_map_length > 0) {
215 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
216
217 for (int i = 0; i < constant_pool_map_length; i++) {
218 int x = reference_map.at(i);
219 assert(x == (int)(jushort) x, "klass index is too big");
220 om->at_put(i, (jushort)x);
221 }
222 set_reference_map(om);
223 }
224
225 // Create Java array for holding resolved strings, methodHandles,
226 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
227 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
228 HandleMark hm(THREAD);
229 Handle refs_handle (THREAD, stom); // must handleize.
230 set_resolved_references(loader_data->add_handle(refs_handle));
231
232 // Create a "scratch" copy of the resolved references array to archive
233 if (CDSConfig::is_dumping_heap()) {
234 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
235 HeapShared::add_scratch_resolved_references(this, scratch_references);
236 }
237 }
238 }
239
240 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
241 // A ConstantPool can't possibly have 0xffff valid class entries,
242 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
243 // entry for the class's name. So at most we will have 0xfffe class entries.
244 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
245 // UnresolvedKlass entries that are temporarily created during class redefinition.
246 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
247 assert(resolved_klasses() == nullptr, "sanity");
248 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
249 set_resolved_klasses(rk);
250 }
251
252 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
253 int len = length();
254 int num_klasses = 0;
255 for (int i = 1; i <len; i++) {
256 switch (tag_at(i).value()) {
257 case JVM_CONSTANT_ClassIndex:
258 {
259 const int class_index = klass_index_at(i);
260 unresolved_klass_at_put(i, class_index, num_klasses++);
261 }
262 break;
263 #ifndef PRODUCT
264 case JVM_CONSTANT_Class:
265 case JVM_CONSTANT_UnresolvedClass:
266 case JVM_CONSTANT_UnresolvedClassInError:
267 // All of these should have been reverted back to Unresolved before calling
268 // this function.
269 ShouldNotReachHere();
270 #endif
271 }
272 }
273 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
274 }
275
276 // Hidden class support:
277 void ConstantPool::klass_at_put(int class_index, Klass* k) {
278 assert(k != nullptr, "must be valid klass");
279 CPKlassSlot kslot = klass_slot_at(class_index);
280 int resolved_klass_index = kslot.resolved_klass_index();
281 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
282 Atomic::release_store(adr, k);
283
284 // The interpreter assumes when the tag is stored, the klass is resolved
285 // and the Klass* non-null, so we need hardware store ordering here.
286 release_tag_at_put(class_index, JVM_CONSTANT_Class);
287 }
288
289 #if INCLUDE_CDS_JAVA_HEAP
290 template <typename Function>
291 void ConstantPool::iterate_archivable_resolved_references(Function function) {
292 objArrayOop rr = resolved_references();
293 if (rr != nullptr && cache() != nullptr && CDSConfig::is_dumping_method_handles()) {
294 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
295 if (indy_entries != nullptr) {
296 for (int i = 0; i < indy_entries->length(); i++) {
297 ResolvedIndyEntry *rie = indy_entries->adr_at(i);
298 if (rie->is_resolved() && AOTConstantPoolResolver::is_resolution_deterministic(this, rie->constant_pool_index())) {
299 int rr_index = rie->resolved_references_index();
300 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
301 function(rr_index);
302
303 // Save the BSM as well (sometimes the JIT looks up the BSM it for replay)
304 int indy_cp_index = rie->constant_pool_index();
305 int bsm_mh_cp_index = bootstrap_method_ref_index_at(indy_cp_index);
306 int bsm_rr_index = cp_to_object_index(bsm_mh_cp_index);
307 assert(resolved_reference_at(bsm_rr_index) != nullptr, "must exist");
308 function(bsm_rr_index);
309 }
310 }
311 }
312
313 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
314 if (method_entries != nullptr) {
315 for (int i = 0; i < method_entries->length(); i++) {
316 ResolvedMethodEntry* rme = method_entries->adr_at(i);
317 if (rme->is_resolved(Bytecodes::_invokehandle) && rme->has_appendix() &&
318 cache()->can_archive_resolved_method(this, rme)) {
319 int rr_index = rme->resolved_references_index();
320 assert(resolved_reference_at(rr_index) != nullptr, "must exist");
321 function(rr_index);
322 }
323 }
324 }
325 }
326 }
327
328 // Returns the _resolved_reference array after removing unarchivable items from it.
329 // Returns null if this class is not supported, or _resolved_reference doesn't exist.
330 objArrayOop ConstantPool::prepare_resolved_references_for_archiving() {
331 if (_cache == nullptr) {
332 return nullptr; // nothing to do
333 }
334
335 InstanceKlass *ik = pool_holder();
336 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
337 // Archiving resolved references for classes from non-builtin loaders
338 // is not yet supported.
339 return nullptr;
340 }
341
342 objArrayOop rr = resolved_references();
343 if (rr != nullptr) {
344 ResourceMark rm;
345 int rr_len = rr->length();
346 GrowableArray<bool> keep_resolved_refs(rr_len, rr_len, false);
347
348 iterate_archivable_resolved_references([&](int rr_index) {
349 keep_resolved_refs.at_put(rr_index, true);
350 });
351
352 objArrayOop scratch_rr = HeapShared::scratch_resolved_references(this);
353 Array<u2>* ref_map = reference_map();
354 int ref_map_len = ref_map == nullptr ? 0 : ref_map->length();
355 for (int i = 0; i < rr_len; i++) {
356 oop obj = rr->obj_at(i);
357 scratch_rr->obj_at_put(i, nullptr);
358 if (obj != nullptr) {
359 if (i < ref_map_len) {
360 int index = object_to_cp_index(i);
361 if (tag_at(index).is_string()) {
362 assert(java_lang_String::is_instance(obj), "must be");
363 if (!ArchiveHeapWriter::is_string_too_large_to_archive(obj)) {
364 scratch_rr->obj_at_put(i, obj);
365 }
366 continue;
367 }
368 }
369
370 if (keep_resolved_refs.at(i)) {
371 scratch_rr->obj_at_put(i, obj);
372 }
373 }
374 }
375 return scratch_rr;
376 }
377 return rr;
378 }
379 #endif
380
381 #if INCLUDE_CDS
382 // CDS support. Create a new resolved_references array.
383 void ConstantPool::restore_unshareable_info(TRAPS) {
384 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
385 return;
386 }
387 assert(is_constantPool(), "ensure C++ vtable is restored");
388 assert(on_stack(), "should always be set for shared constant pools");
389 assert(is_shared(), "should always be set for shared constant pools");
390 if (is_for_method_handle_intrinsic()) {
391 // See the same check in remove_unshareable_info() below.
392 assert(cache() == nullptr, "must not have cpCache");
393 return;
394 }
395 assert(_cache != nullptr, "constant pool _cache should not be null");
396
397 // Only create the new resolved references array if it hasn't been attempted before
398 if (resolved_references() != nullptr) return;
399
400 if (vmClasses::Object_klass_loaded()) {
401 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
402 #if INCLUDE_CDS_JAVA_HEAP
403 if (ArchiveHeapLoader::is_in_use() &&
404 _cache->archived_references() != nullptr) {
405 oop archived = _cache->archived_references();
406 // Create handle for the archived resolved reference array object
407 HandleMark hm(THREAD);
408 Handle refs_handle(THREAD, archived);
409 set_resolved_references(loader_data->add_handle(refs_handle));
410 _cache->clear_archived_references();
411 } else
412 #endif
413 {
414 // No mapped archived resolved reference array
415 // Recreate the object array and add to ClassLoaderData.
416 int map_length = resolved_reference_length();
417 if (map_length > 0) {
418 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
419 HandleMark hm(THREAD);
420 Handle refs_handle(THREAD, stom); // must handleize.
421 set_resolved_references(loader_data->add_handle(refs_handle));
422 }
423 }
424 }
425
426 if (CDSConfig::is_dumping_final_static_archive() && CDSConfig::is_dumping_heap() && resolved_references() != nullptr) {
427 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), resolved_references()->length(), CHECK);
428 HeapShared::add_scratch_resolved_references(this, scratch_references);
429 }
430 }
431
432 void ConstantPool::remove_unshareable_info() {
433 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
434 // The _on_stack flag is used to prevent ConstantPools from deallocation during
435 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
436 // we always set _on_stack to true to avoid having to change _flags during runtime.
437 _flags |= (_on_stack | _is_shared);
438
439 if (is_for_method_handle_intrinsic()) {
440 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
441 // that need to be removed/restored. It has no cpCache since the intrinsic methods
442 // don't have any bytecodes.
443 assert(cache() == nullptr, "must not have cpCache");
444 return;
445 }
446
447 bool update_resolved_reference = true;
448 if (CDSConfig::is_dumping_final_static_archive()) {
449 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
450 InstanceKlass* src_holder = src_cp->pool_holder();
451 if (src_holder->defined_by_other_loaders()) {
452 // Unregistered classes are not loaded in the AOT assembly phase. The resolved reference length
453 // is already saved during the training run.
454 precond(!src_holder->is_loaded());
455 precond(resolved_reference_length() >= 0);
456 precond(resolved_references() == nullptr);
457 update_resolved_reference = false;
458 }
459 }
460
461 // resolved_references(): remember its length. If it cannot be restored
462 // from the archived heap objects at run time, we need to dynamically allocate it.
463 if (update_resolved_reference && cache() != nullptr) {
464 set_resolved_reference_length(
465 resolved_references() != nullptr ? resolved_references()->length() : 0);
466 set_resolved_references(OopHandle());
467 }
468 remove_unshareable_entries();
469 }
470
471 static const char* get_type(Klass* k) {
472 const char* type;
473 Klass* src_k;
474 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
475 src_k = ArchiveBuilder::current()->get_source_addr(k);
476 } else {
477 src_k = k;
478 }
479
480 if (src_k->is_objArray_klass()) {
481 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
482 assert(!src_k->is_objArray_klass(), "sanity");
483 assert(src_k->is_instance_klass() || src_k->is_typeArray_klass(), "Sanity check");
484 }
485
486 if (src_k->is_typeArray_klass()) {
487 type = "prim";
488 } else {
489 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
490 if (src_ik->defined_by_boot_loader()) {
491 return "boot";
492 } else if (src_ik->defined_by_platform_loader()) {
493 return "plat";
494 } else if (src_ik->defined_by_app_loader()) {
495 return "app";
496 } else {
497 return "unreg";
498 }
499 }
500
501 return type;
502 }
503
504 void ConstantPool::remove_unshareable_entries() {
505 ResourceMark rm;
506 log_info(aot, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
507 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
508 int cp_tag = tag_at(cp_index).value();
509 switch (cp_tag) {
510 case JVM_CONSTANT_UnresolvedClass:
511 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, false);
512 break;
513 case JVM_CONSTANT_UnresolvedClassInError:
514 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
515 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false, true);
516 break;
517 case JVM_CONSTANT_MethodHandleInError:
518 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
519 break;
520 case JVM_CONSTANT_MethodTypeInError:
521 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
522 break;
523 case JVM_CONSTANT_DynamicInError:
524 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
525 break;
526 case JVM_CONSTANT_Class:
527 remove_resolved_klass_if_non_deterministic(cp_index);
528 break;
529 default:
530 break;
531 }
532 }
533
534 if (cache() != nullptr) {
535 // cache() is null if this class is not yet linked.
536 cache()->remove_unshareable_info();
537 }
538 }
539
540 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
541 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
542 assert(tag_at(cp_index).is_klass(), "must be resolved");
543
544 Klass* k = resolved_klass_at(cp_index);
545 bool can_archive;
546
547 if (k == nullptr) {
548 // We'd come here if the referenced class has been excluded via
549 // SystemDictionaryShared::is_excluded_class(). As a result, ArchiveBuilder
550 // has cleared the resolved_klasses()->at(...) pointer to null. Thus, we
551 // need to revert the tag to JVM_CONSTANT_UnresolvedClass.
552 can_archive = false;
553 } else {
554 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
555 can_archive = AOTConstantPoolResolver::is_resolution_deterministic(src_cp, cp_index);
556 }
557
558 if (!can_archive) {
559 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
560 // This might be at a safepoint but do this in the right order.
561 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
562 resolved_klasses()->at_put(resolved_klass_index, nullptr);
563 }
564
565 LogStreamHandle(Trace, aot, resolve) log;
566 if (log.is_enabled()) {
567 ResourceMark rm;
568 log.print("%s klass CP entry [%3d]: %s %s",
569 (can_archive ? "archived" : "reverted"),
570 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
571 if (can_archive) {
572 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
573 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
574 } else {
575 Symbol* name = klass_name_at(cp_index);
576 log.print(" => %s", name->as_C_string());
577 }
578 }
579
580 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(can_archive, /*reverted=*/!can_archive);
581 }
582 #endif // INCLUDE_CDS
583
584 int ConstantPool::cp_to_object_index(int cp_index) {
585 // this is harder don't do this so much.
586 int i = reference_map()->find(checked_cast<u2>(cp_index));
587 // We might not find the index for jsr292 call.
588 return (i < 0) ? _no_index_sentinel : i;
589 }
590
591 void ConstantPool::string_at_put(int obj_index, oop str) {
592 oop result = set_resolved_reference_at(obj_index, str);
593 assert(result == nullptr || result == str, "Only set once or to the same string.");
594 }
595
596 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
597 ResourceMark rm;
598 int line_number = -1;
599 const char * source_file = nullptr;
600 if (JavaThread::current()->has_last_Java_frame()) {
601 // try to identify the method which called this function.
602 vframeStream vfst(JavaThread::current());
603 if (!vfst.at_end()) {
604 line_number = vfst.method()->line_number_from_bci(vfst.bci());
605 Symbol* s = vfst.method()->method_holder()->source_file_name();
606 if (s != nullptr) {
607 source_file = s->as_C_string();
608 }
609 }
610 }
611 if (k != this_cp->pool_holder()) {
612 // only print something if the classes are different
613 if (source_file != nullptr) {
614 log_debug(class, resolve)("%s %s %s:%d",
615 this_cp->pool_holder()->external_name(),
616 k->external_name(), source_file, line_number);
617 } else {
618 log_debug(class, resolve)("%s %s",
619 this_cp->pool_holder()->external_name(),
620 k->external_name());
621 }
622 }
623 }
624
625 void check_is_inline_type(Klass* k, TRAPS) {
626 if (!k->is_inline_klass()) {
627 THROW(vmSymbols::java_lang_IncompatibleClassChangeError());
628 }
629 }
630
631 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
632 TRAPS) {
633 JavaThread* javaThread = THREAD;
634
635 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
636 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
637 // the entry and tag is not updated atomically.
638 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
639 int resolved_klass_index = kslot.resolved_klass_index();
640 int name_index = kslot.name_index();
641 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
642
643 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
644 // the unresolved_klasses() array.
645 if (this_cp->tag_at(cp_index).is_klass()) {
646 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
647 assert(klass != nullptr, "must be resolved");
648 return klass;
649 }
650
651 // This tag doesn't change back to unresolved class unless at a safepoint.
652 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
653 // The original attempt to resolve this constant pool entry failed so find the
654 // class of the original error and throw another error of the same class
655 // (JVMS 5.4.3).
656 // If there is a detail message, pass that detail message to the error.
657 // The JVMS does not strictly require us to duplicate the same detail message,
658 // or any internal exception fields such as cause or stacktrace. But since the
659 // detail message is often a class name or other literal string, we will repeat it
660 // if we can find it in the symbol table.
661 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
662 ShouldNotReachHere();
663 }
664
665 HandleMark hm(THREAD);
666 Handle mirror_handle;
667 Symbol* name = this_cp->symbol_at(name_index);
668 bool inline_type_signature = false;
669 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
670
671 Klass* k;
672 {
673 // Turn off the single stepping while doing class resolution
674 JvmtiHideSingleStepping jhss(javaThread);
675 k = SystemDictionary::resolve_or_fail(name, loader, true, THREAD);
676 } // JvmtiHideSingleStepping jhss(javaThread);
677 if (inline_type_signature) {
678 name->decrement_refcount();
679 }
680
681 if (!HAS_PENDING_EXCEPTION) {
682 // preserve the resolved klass from unloading
683 mirror_handle = Handle(THREAD, k->java_mirror());
684 // Do access check for klasses
685 verify_constant_pool_resolve(this_cp, k, THREAD);
686 }
687
688 if (!HAS_PENDING_EXCEPTION && inline_type_signature) {
689 check_is_inline_type(k, THREAD);
690 }
691
692 if (!HAS_PENDING_EXCEPTION) {
693 Klass* bottom_klass = nullptr;
694 if (k->is_objArray_klass()) {
695 bottom_klass = ObjArrayKlass::cast(k)->bottom_klass();
696 assert(bottom_klass != nullptr, "Should be set");
697 assert(bottom_klass->is_instance_klass() || bottom_klass->is_typeArray_klass(), "Sanity check");
698 } else if (k->is_flatArray_klass()) {
699 bottom_klass = FlatArrayKlass::cast(k)->element_klass();
700 assert(bottom_klass != nullptr, "Should be set");
701 }
702 }
703
704 // Failed to resolve class. We must record the errors so that subsequent attempts
705 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
706 if (HAS_PENDING_EXCEPTION) {
707 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
708 // If CHECK_NULL above doesn't return the exception, that means that
709 // some other thread has beaten us and has resolved the class.
710 // To preserve old behavior, we return the resolved class.
711 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
712 assert(klass != nullptr, "must be resolved if exception was cleared");
713 return klass;
714 }
715
716 // logging for class+resolve.
717 if (log_is_enabled(Debug, class, resolve)){
718 trace_class_resolution(this_cp, k);
719 }
720
721 // The interpreter assumes when the tag is stored, the klass is resolved
722 // and the Klass* stored in _resolved_klasses is non-null, so we need
723 // hardware store ordering here.
724 // We also need to CAS to not overwrite an error from a racing thread.
725 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
726 Atomic::release_store(adr, k);
727
728 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
729 (jbyte)JVM_CONSTANT_UnresolvedClass,
730 (jbyte)JVM_CONSTANT_Class);
731
732 // We need to recheck exceptions from racing thread and return the same.
733 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
734 // Remove klass.
735 Atomic::store(adr, (Klass*)nullptr);
736 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
737 }
738
739 return k;
740 }
741
742
743 // Does not update ConstantPool* - to avoid any exception throwing. Used
744 // by compiler and exception handling. Also used to avoid classloads for
745 // instanceof operations. Returns null if the class has not been loaded or
746 // if the verification of constant pool failed
747 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
748 CPKlassSlot kslot = this_cp->klass_slot_at(which);
749 int resolved_klass_index = kslot.resolved_klass_index();
750 int name_index = kslot.name_index();
751 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
752
753 if (this_cp->tag_at(which).is_klass()) {
754 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
755 assert(k != nullptr, "must be resolved");
756 return k;
757 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
758 return nullptr;
759 } else {
760 Thread* current = Thread::current();
761 HandleMark hm(current);
762 Symbol* name = this_cp->symbol_at(name_index);
763 oop loader = this_cp->pool_holder()->class_loader();
764 Handle h_loader (current, loader);
765 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader);
766
767 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
768 if (k != nullptr && current->is_Java_thread()) {
769 // Make sure that resolving is legal
770 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
771 ExceptionMark em(THREAD);
772 // return null if verification fails
773 verify_constant_pool_resolve(this_cp, k, THREAD);
774 if (HAS_PENDING_EXCEPTION) {
775 CLEAR_PENDING_EXCEPTION;
776 return nullptr;
777 }
778 return k;
779 } else {
780 return k;
781 }
782 }
783 }
784
785 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
786 int which) {
787 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
788 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
789 // FIXME: should be an assert
790 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
791 return nullptr;
792 }
793 return cpool->cache()->method_if_resolved(which);
794 }
795
796
797 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
798 if (cpool->cache() == nullptr) return false; // nothing to load yet
799 if (code == Bytecodes::_invokedynamic) {
800 return cpool->resolved_indy_entry_at(which)->has_appendix();
801 } else {
802 return cpool->resolved_method_entry_at(which)->has_appendix();
803 }
804 }
805
806 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
807 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
808 if (code == Bytecodes::_invokedynamic) {
809 return cpool->resolved_reference_from_indy(which);
810 } else {
811 return cpool->cache()->appendix_if_resolved(which);
812 }
813 }
814
815
816 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
817 if (cpool->cache() == nullptr) return false; // nothing to load yet
818 if (code == Bytecodes::_invokedynamic) {
819 return cpool->resolved_indy_entry_at(which)->has_local_signature();
820 } else {
821 return cpool->resolved_method_entry_at(which)->has_local_signature();
822 }
823 }
824
825 // Translate index, which could be CPCache index or Indy index, to a constant pool index
826 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
827 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
828 switch(code) {
829 case Bytecodes::_invokedynamic:
830 return invokedynamic_bootstrap_ref_index_at(index);
831 case Bytecodes::_getfield:
832 case Bytecodes::_getstatic:
833 case Bytecodes::_putfield:
834 case Bytecodes::_putstatic:
835 return resolved_field_entry_at(index)->constant_pool_index();
836 case Bytecodes::_invokeinterface:
837 case Bytecodes::_invokehandle:
838 case Bytecodes::_invokespecial:
839 case Bytecodes::_invokestatic:
840 case Bytecodes::_invokevirtual:
841 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
842 return resolved_method_entry_at(index)->constant_pool_index();
843 default:
844 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
845 }
846 }
847
848 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
849 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
850 switch(code) {
851 case Bytecodes::_invokedynamic:
852 return resolved_indy_entry_at(index)->is_resolved();
853
854 case Bytecodes::_getfield:
855 case Bytecodes::_getstatic:
856 case Bytecodes::_putfield:
857 case Bytecodes::_putstatic:
858 return resolved_field_entry_at(index)->is_resolved(code);
859
860 case Bytecodes::_invokeinterface:
861 case Bytecodes::_invokehandle:
862 case Bytecodes::_invokespecial:
863 case Bytecodes::_invokestatic:
864 case Bytecodes::_invokevirtual:
865 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
866 return resolved_method_entry_at(index)->is_resolved(code);
867
868 default:
869 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
870 }
871 }
872
873 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
874 if (tag_at(cp_index).has_bootstrap()) {
875 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
876 assert(tag_at(pool_index).is_name_and_type(), "");
877 return pool_index;
878 }
879 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
880 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
881 jint ref_index = *int_at_addr(cp_index);
882 return extract_high_short_from_int(ref_index);
883 }
884
885 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
886 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
887 }
888
889 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
890 // which may be either a Constant Pool index or a rewritten index
891 int pool_index = which;
892 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
893 pool_index = to_cp_index(which, code);
894 return tag_at(pool_index);
895 }
896
897 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
898 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
899 jint ref_index = *int_at_addr(cp_index);
900 return extract_low_short_from_int(ref_index);
901 }
902
903 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
904 assert(code != Bytecodes::_invokedynamic,
905 "an invokedynamic instruction does not have a klass");
906 return uncached_klass_ref_index_at(to_cp_index(index, code));
907 }
908
909 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
910 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
911 return; // short cut, typeArray klass is always accessible
912 }
913 Klass* holder = this_cp->pool_holder();
914 LinkResolver::check_klass_accessibility(holder, k, CHECK);
915 }
916
917
918 u2 ConstantPool::name_ref_index_at(int cp_index) {
919 jint ref_index = name_and_type_at(cp_index);
920 return extract_low_short_from_int(ref_index);
921 }
922
923
924 u2 ConstantPool::signature_ref_index_at(int cp_index) {
925 jint ref_index = name_and_type_at(cp_index);
926 return extract_high_short_from_int(ref_index);
927 }
928
929
930 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
931 return klass_at(klass_ref_index_at(which, code), THREAD);
932 }
933
934 Symbol* ConstantPool::klass_name_at(int cp_index) const {
935 return symbol_at(klass_slot_at(cp_index).name_index());
936 }
937
938 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
939 jint ref_index = klass_ref_index_at(which, code);
940 return klass_at_noresolve(ref_index);
941 }
942
943 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
944 jint ref_index = uncached_klass_ref_index_at(cp_index);
945 return klass_at_noresolve(ref_index);
946 }
947
948 char* ConstantPool::string_at_noresolve(int cp_index) {
949 return unresolved_string_at(cp_index)->as_C_string();
950 }
951
952 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
953 return Signature::basic_type(symbol_at(cp_index));
954 }
955
956
957 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
958 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
959 if (this_cp->tag_at(index).is_string()) {
960 this_cp->string_at(index, CHECK);
961 }
962 }
963 }
964
965 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
966 // Note: caller needs ResourceMark
967
968 // Dig out the detailed message to reuse if possible
969 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
970 if (msg != nullptr) {
971 return msg;
972 }
973
974 Symbol* message = nullptr;
975 // Return specific message for the tag
976 switch (tag.value()) {
977 case JVM_CONSTANT_UnresolvedClass:
978 // return the class name in the error message
979 message = this_cp->klass_name_at(which);
980 break;
981 case JVM_CONSTANT_MethodHandle:
982 // return the method handle name in the error message
983 message = this_cp->method_handle_name_ref_at(which);
984 break;
985 case JVM_CONSTANT_MethodType:
986 // return the method type signature in the error message
987 message = this_cp->method_type_signature_at(which);
988 break;
989 case JVM_CONSTANT_Dynamic:
990 // return the name of the condy in the error message
991 message = this_cp->uncached_name_ref_at(which);
992 break;
993 default:
994 ShouldNotReachHere();
995 }
996
997 return message != nullptr ? message->as_C_string() : nullptr;
998 }
999
1000 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
1001 constantTag tag, oop pending_exception) {
1002
1003 ResourceMark rm(current);
1004 Symbol* error = pending_exception->klass()->name();
1005 oop cause = java_lang_Throwable::cause(pending_exception);
1006
1007 // Also dig out the exception cause, if present.
1008 Symbol* cause_sym = nullptr;
1009 const char* cause_msg = nullptr;
1010 if (cause != nullptr && cause != pending_exception) {
1011 cause_sym = cause->klass()->name();
1012 cause_msg = java_lang_Throwable::message_as_utf8(cause);
1013 }
1014
1015 const char* message = exception_message(this_cp, which, tag, pending_exception);
1016 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1017 }
1018
1019
1020 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1021 ResourceMark rm(THREAD);
1022 const char* message = nullptr;
1023 Symbol* cause = nullptr;
1024 const char* cause_msg = nullptr;
1025 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1026 assert(error != nullptr, "checking");
1027
1028 CLEAR_PENDING_EXCEPTION;
1029 if (message != nullptr) {
1030 if (cause != nullptr) {
1031 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1032 THROW_MSG_CAUSE(error, message, h_cause);
1033 } else {
1034 THROW_MSG(error, message);
1035 }
1036 } else {
1037 if (cause != nullptr) {
1038 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1039 THROW_CAUSE(error, h_cause);
1040 } else {
1041 THROW(error);
1042 }
1043 }
1044 }
1045
1046 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1047 // exception in the resolution error table, so that the same exception is thrown again.
1048 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1049 constantTag tag, TRAPS) {
1050
1051 int error_tag = tag.error_value();
1052
1053 if (!PENDING_EXCEPTION->
1054 is_a(vmClasses::LinkageError_klass())) {
1055 // Just throw the exception and don't prevent these classes from
1056 // being loaded due to virtual machine errors like StackOverflow
1057 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1058 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1059 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1060 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1061 // CAS in the tag. If a thread beat us to registering this error that's fine.
1062 // If another thread resolved the reference, this is a race condition. This
1063 // thread may have had a security manager or something temporary.
1064 // This doesn't deterministically get an error. So why do we save this?
1065 // We save this because jvmti can add classes to the bootclass path after
1066 // this error, so it needs to get the same error if the error is first.
1067 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1068 (jbyte)tag.value(),
1069 (jbyte)error_tag);
1070 if (old_tag != error_tag && old_tag != tag.value()) {
1071 // MethodHandles and MethodType doesn't change to resolved version.
1072 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1073 // Forget the exception and use the resolved class.
1074 CLEAR_PENDING_EXCEPTION;
1075 }
1076 } else {
1077 // some other thread put this in error state
1078 throw_resolution_error(this_cp, cp_index, CHECK);
1079 }
1080 }
1081
1082 constantTag ConstantPool::constant_tag_at(int cp_index) {
1083 constantTag tag = tag_at(cp_index);
1084 if (tag.is_dynamic_constant()) {
1085 BasicType bt = basic_type_for_constant_at(cp_index);
1086 return constantTag(constantTag::type2tag(bt));
1087 }
1088 return tag;
1089 }
1090
1091 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1092 constantTag tag = tag_at(cp_index);
1093 if (tag.is_dynamic_constant() ||
1094 tag.is_dynamic_constant_in_error()) {
1095 // have to look at the signature for this one
1096 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1097 return Signature::basic_type(constant_type);
1098 }
1099 return tag.basic_type();
1100 }
1101
1102 // Called to resolve constants in the constant pool and return an oop.
1103 // Some constant pool entries cache their resolved oop. This is also
1104 // called to create oops from constants to use in arguments for invokedynamic
1105 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1106 int cp_index, int cache_index,
1107 bool* status_return, TRAPS) {
1108 oop result_oop = nullptr;
1109
1110 if (cache_index == _possible_index_sentinel) {
1111 // It is possible that this constant is one which is cached in the objects.
1112 // We'll do a linear search. This should be OK because this usage is rare.
1113 // FIXME: If bootstrap specifiers stress this code, consider putting in
1114 // a reverse index. Binary search over a short array should do it.
1115 assert(cp_index > 0, "valid constant pool index");
1116 cache_index = this_cp->cp_to_object_index(cp_index);
1117 }
1118 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1119 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1120
1121 if (cache_index >= 0) {
1122 result_oop = this_cp->resolved_reference_at(cache_index);
1123 if (result_oop != nullptr) {
1124 if (result_oop == Universe::the_null_sentinel()) {
1125 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1126 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1127 result_oop = nullptr;
1128 }
1129 if (status_return != nullptr) (*status_return) = true;
1130 return result_oop;
1131 // That was easy...
1132 }
1133 cp_index = this_cp->object_to_cp_index(cache_index);
1134 }
1135
1136 jvalue prim_value; // temp used only in a few cases below
1137
1138 constantTag tag = this_cp->tag_at(cp_index);
1139
1140 if (status_return != nullptr) {
1141 // don't trigger resolution if the constant might need it
1142 switch (tag.value()) {
1143 case JVM_CONSTANT_Class:
1144 assert(this_cp->resolved_klass_at(cp_index) != nullptr, "must be resolved");
1145 break;
1146 case JVM_CONSTANT_String:
1147 case JVM_CONSTANT_Integer:
1148 case JVM_CONSTANT_Float:
1149 case JVM_CONSTANT_Long:
1150 case JVM_CONSTANT_Double:
1151 // these guys trigger OOM at worst
1152 break;
1153 default:
1154 (*status_return) = false;
1155 return nullptr;
1156 }
1157 // from now on there is either success or an OOME
1158 (*status_return) = true;
1159 }
1160
1161 switch (tag.value()) {
1162
1163 case JVM_CONSTANT_UnresolvedClass:
1164 case JVM_CONSTANT_Class:
1165 {
1166 assert(cache_index == _no_index_sentinel, "should not have been set");
1167 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1168 // ldc wants the java mirror.
1169 result_oop = resolved->java_mirror();
1170 break;
1171 }
1172
1173 case JVM_CONSTANT_Dynamic:
1174 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1175 ClassLoader::perf_resolve_invokedynamic_count());
1176
1177 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1178 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1179
1180 // The initial step in resolving an unresolved symbolic reference to a
1181 // dynamically-computed constant is to resolve the symbolic reference to a
1182 // method handle which will be the bootstrap method for the dynamically-computed
1183 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1184 // method fails, then a MethodHandleInError is stored at the corresponding
1185 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1186 // set a DynamicConstantInError here since any subsequent use of this
1187 // bootstrap method will encounter the resolution of MethodHandleInError.
1188 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1189 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1190 // for the bootstrap_specifier created above.
1191 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1192 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1193 if (HAS_PENDING_EXCEPTION) {
1194 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1195 // will check for a LinkageError and store a DynamicConstantInError.
1196 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1197 }
1198 result_oop = bootstrap_specifier.resolved_value()();
1199 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1200 if (!is_reference_type(type)) {
1201 // Make sure the primitive value is properly boxed.
1202 // This is a JDK responsibility.
1203 const char* fail = nullptr;
1204 if (result_oop == nullptr) {
1205 fail = "null result instead of box";
1206 } else if (!is_java_primitive(type)) {
1207 // FIXME: support value types via unboxing
1208 fail = "can only handle references and primitives";
1209 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1210 fail = "primitive is not properly boxed";
1211 }
1212 if (fail != nullptr) {
1213 // Since this exception is not a LinkageError, throw exception
1214 // but do not save a DynamicInError resolution result.
1215 // See section 5.4.3 of the VM spec.
1216 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1217 }
1218 }
1219
1220 LogTarget(Debug, methodhandles, condy) lt_condy;
1221 if (lt_condy.is_enabled()) {
1222 LogStream ls(lt_condy);
1223 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1224 }
1225 break;
1226 }
1227
1228 case JVM_CONSTANT_String:
1229 assert(cache_index != _no_index_sentinel, "should have been set");
1230 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1231 break;
1232
1233 case JVM_CONSTANT_MethodHandle:
1234 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1235 ClassLoader::perf_resolve_method_handle_count());
1236
1237 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1238 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1239 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1240 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1241 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1242 { ResourceMark rm(THREAD);
1243 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1244 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1245 callee_index, name->as_C_string(), signature->as_C_string());
1246 }
1247
1248 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1249 if (HAS_PENDING_EXCEPTION) {
1250 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1251 }
1252
1253 // Check constant pool method consistency
1254 if ((callee->is_interface() && m_tag.is_method()) ||
1255 (!callee->is_interface() && m_tag.is_interface_method())) {
1256 ResourceMark rm(THREAD);
1257 stringStream ss;
1258 ss.print("Inconsistent constant pool data in classfile for class %s. "
1259 "Method '", callee->name()->as_C_string());
1260 signature->print_as_signature_external_return_type(&ss);
1261 ss.print(" %s(", name->as_C_string());
1262 signature->print_as_signature_external_parameters(&ss);
1263 ss.print(")' at index %d is %s and should be %s",
1264 cp_index,
1265 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1266 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1267 // Names are all known to be < 64k so we know this formatted message is not excessively large.
1268 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1269 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1270 }
1271
1272 Klass* klass = this_cp->pool_holder();
1273 HandleMark hm(THREAD);
1274 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1275 callee, name, signature,
1276 THREAD);
1277 if (HAS_PENDING_EXCEPTION) {
1278 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1279 }
1280 result_oop = value();
1281 break;
1282 }
1283
1284 case JVM_CONSTANT_MethodType:
1285 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1286 ClassLoader::perf_resolve_method_type_count());
1287
1288 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1289 { ResourceMark rm(THREAD);
1290 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1291 cp_index, this_cp->method_type_index_at(cp_index),
1292 signature->as_C_string());
1293 }
1294 Klass* klass = this_cp->pool_holder();
1295 HandleMark hm(THREAD);
1296 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1297 result_oop = value();
1298 if (HAS_PENDING_EXCEPTION) {
1299 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1300 }
1301 break;
1302 }
1303
1304 case JVM_CONSTANT_Integer:
1305 assert(cache_index == _no_index_sentinel, "should not have been set");
1306 prim_value.i = this_cp->int_at(cp_index);
1307 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1308 break;
1309
1310 case JVM_CONSTANT_Float:
1311 assert(cache_index == _no_index_sentinel, "should not have been set");
1312 prim_value.f = this_cp->float_at(cp_index);
1313 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1314 break;
1315
1316 case JVM_CONSTANT_Long:
1317 assert(cache_index == _no_index_sentinel, "should not have been set");
1318 prim_value.j = this_cp->long_at(cp_index);
1319 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1320 break;
1321
1322 case JVM_CONSTANT_Double:
1323 assert(cache_index == _no_index_sentinel, "should not have been set");
1324 prim_value.d = this_cp->double_at(cp_index);
1325 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1326 break;
1327
1328 case JVM_CONSTANT_UnresolvedClassInError:
1329 case JVM_CONSTANT_DynamicInError:
1330 case JVM_CONSTANT_MethodHandleInError:
1331 case JVM_CONSTANT_MethodTypeInError:
1332 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1333 break;
1334
1335 default:
1336 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1337 break;
1338 }
1339
1340 if (cache_index >= 0) {
1341 // Benign race condition: resolved_references may already be filled in.
1342 // The important thing here is that all threads pick up the same result.
1343 // It doesn't matter which racing thread wins, as long as only one
1344 // result is used by all threads, and all future queries.
1345 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1346 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1347 if (old_result == nullptr) {
1348 return result_oop; // was installed
1349 } else {
1350 // Return the winning thread's result. This can be different than
1351 // the result here for MethodHandles.
1352 if (old_result == Universe::the_null_sentinel())
1353 old_result = nullptr;
1354 return old_result;
1355 }
1356 } else {
1357 assert(result_oop != Universe::the_null_sentinel(), "");
1358 return result_oop;
1359 }
1360 }
1361
1362 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1363 Symbol* sym = unresolved_string_at(cp_index);
1364 oop str = StringTable::intern(sym, CHECK_(nullptr));
1365 assert(java_lang_String::is_instance(str), "must be string");
1366 return str;
1367 }
1368
1369 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1370 int start_arg, int end_arg,
1371 objArrayHandle info, int pos,
1372 bool must_resolve, Handle if_not_available,
1373 TRAPS) {
1374 int limit = pos + end_arg - start_arg;
1375 // checks: cp_index in range [0..this_cp->length),
1376 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1377 // info array non-null, pos..limit in [0..info.length]
1378 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1379 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1380 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1381 (0 > start_arg || start_arg > end_arg) ||
1382 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1383 (0 > pos || pos > limit) ||
1384 (info.is_null() || limit > info->length())) {
1385 // An index or something else went wrong; throw an error.
1386 // Since this is an internal API, we don't expect this,
1387 // so we don't bother to craft a nice message.
1388 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1389 }
1390 // now we can loop safely
1391 int info_i = pos;
1392 for (int i = start_arg; i < end_arg; i++) {
1393 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1394 oop arg_oop;
1395 if (must_resolve) {
1396 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1397 } else {
1398 bool found_it = false;
1399 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1400 if (!found_it) arg_oop = if_not_available();
1401 }
1402 info->obj_at_put(info_i++, arg_oop);
1403 }
1404 }
1405
1406 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1407 // If the string has already been interned, this entry will be non-null
1408 oop str = this_cp->resolved_reference_at(obj_index);
1409 assert(str != Universe::the_null_sentinel(), "");
1410 if (str != nullptr) return str;
1411 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1412 str = StringTable::intern(sym, CHECK_(nullptr));
1413 this_cp->string_at_put(obj_index, str);
1414 assert(java_lang_String::is_instance(str), "must be string");
1415 return str;
1416 }
1417
1418
1419 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1420 // Names are interned, so we can compare Symbol*s directly
1421 Symbol* cp_name = klass_name_at(cp_index);
1422 return (cp_name == k->name());
1423 }
1424
1425
1426 // Iterate over symbols and decrement ones which are Symbol*s
1427 // This is done during GC.
1428 // Only decrement the UTF8 symbols. Strings point to
1429 // these symbols but didn't increment the reference count.
1430 void ConstantPool::unreference_symbols() {
1431 for (int index = 1; index < length(); index++) { // Index 0 is unused
1432 constantTag tag = tag_at(index);
1433 if (tag.is_symbol()) {
1434 symbol_at(index)->decrement_refcount();
1435 }
1436 }
1437 }
1438
1439
1440 // Compare this constant pool's entry at index1 to the constant pool
1441 // cp2's entry at index2.
1442 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1443 int index2) {
1444
1445 // The error tags are equivalent to non-error tags when comparing
1446 jbyte t1 = tag_at(index1).non_error_value();
1447 jbyte t2 = cp2->tag_at(index2).non_error_value();
1448
1449 // Some classes are pre-resolved (like Throwable) which may lead to
1450 // consider it as a different entry. We then revert them back temporarily
1451 // to ensure proper comparison.
1452 if (t1 == JVM_CONSTANT_Class) {
1453 t1 = JVM_CONSTANT_UnresolvedClass;
1454 }
1455 if (t2 == JVM_CONSTANT_Class) {
1456 t2 = JVM_CONSTANT_UnresolvedClass;
1457 }
1458
1459 if (t1 != t2) {
1460 // Not the same entry type so there is nothing else to check. Note
1461 // that this style of checking will consider resolved/unresolved
1462 // class pairs as different.
1463 // From the ConstantPool* API point of view, this is correct
1464 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1465 // plays out in the context of ConstantPool* merging.
1466 return false;
1467 }
1468
1469 switch (t1) {
1470 case JVM_CONSTANT_ClassIndex:
1471 {
1472 int recur1 = klass_index_at(index1);
1473 int recur2 = cp2->klass_index_at(index2);
1474 if (compare_entry_to(recur1, cp2, recur2)) {
1475 return true;
1476 }
1477 } break;
1478
1479 case JVM_CONSTANT_Double:
1480 {
1481 jdouble d1 = double_at(index1);
1482 jdouble d2 = cp2->double_at(index2);
1483 if (d1 == d2) {
1484 return true;
1485 }
1486 } break;
1487
1488 case JVM_CONSTANT_Fieldref:
1489 case JVM_CONSTANT_InterfaceMethodref:
1490 case JVM_CONSTANT_Methodref:
1491 {
1492 int recur1 = uncached_klass_ref_index_at(index1);
1493 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1494 bool match = compare_entry_to(recur1, cp2, recur2);
1495 if (match) {
1496 recur1 = uncached_name_and_type_ref_index_at(index1);
1497 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1498 if (compare_entry_to(recur1, cp2, recur2)) {
1499 return true;
1500 }
1501 }
1502 } break;
1503
1504 case JVM_CONSTANT_Float:
1505 {
1506 jfloat f1 = float_at(index1);
1507 jfloat f2 = cp2->float_at(index2);
1508 if (f1 == f2) {
1509 return true;
1510 }
1511 } break;
1512
1513 case JVM_CONSTANT_Integer:
1514 {
1515 jint i1 = int_at(index1);
1516 jint i2 = cp2->int_at(index2);
1517 if (i1 == i2) {
1518 return true;
1519 }
1520 } break;
1521
1522 case JVM_CONSTANT_Long:
1523 {
1524 jlong l1 = long_at(index1);
1525 jlong l2 = cp2->long_at(index2);
1526 if (l1 == l2) {
1527 return true;
1528 }
1529 } break;
1530
1531 case JVM_CONSTANT_NameAndType:
1532 {
1533 int recur1 = name_ref_index_at(index1);
1534 int recur2 = cp2->name_ref_index_at(index2);
1535 if (compare_entry_to(recur1, cp2, recur2)) {
1536 recur1 = signature_ref_index_at(index1);
1537 recur2 = cp2->signature_ref_index_at(index2);
1538 if (compare_entry_to(recur1, cp2, recur2)) {
1539 return true;
1540 }
1541 }
1542 } break;
1543
1544 case JVM_CONSTANT_StringIndex:
1545 {
1546 int recur1 = string_index_at(index1);
1547 int recur2 = cp2->string_index_at(index2);
1548 if (compare_entry_to(recur1, cp2, recur2)) {
1549 return true;
1550 }
1551 } break;
1552
1553 case JVM_CONSTANT_UnresolvedClass:
1554 {
1555 Symbol* k1 = klass_name_at(index1);
1556 Symbol* k2 = cp2->klass_name_at(index2);
1557 if (k1 == k2) {
1558 return true;
1559 }
1560 } break;
1561
1562 case JVM_CONSTANT_MethodType:
1563 {
1564 int k1 = method_type_index_at(index1);
1565 int k2 = cp2->method_type_index_at(index2);
1566 if (compare_entry_to(k1, cp2, k2)) {
1567 return true;
1568 }
1569 } break;
1570
1571 case JVM_CONSTANT_MethodHandle:
1572 {
1573 int k1 = method_handle_ref_kind_at(index1);
1574 int k2 = cp2->method_handle_ref_kind_at(index2);
1575 if (k1 == k2) {
1576 int i1 = method_handle_index_at(index1);
1577 int i2 = cp2->method_handle_index_at(index2);
1578 if (compare_entry_to(i1, cp2, i2)) {
1579 return true;
1580 }
1581 }
1582 } break;
1583
1584 case JVM_CONSTANT_Dynamic:
1585 {
1586 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1587 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1588 int i1 = bootstrap_methods_attribute_index(index1);
1589 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1590 bool match_entry = compare_entry_to(k1, cp2, k2);
1591 bool match_operand = compare_operand_to(i1, cp2, i2);
1592 return (match_entry && match_operand);
1593 } break;
1594
1595 case JVM_CONSTANT_InvokeDynamic:
1596 {
1597 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1598 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1599 int i1 = bootstrap_methods_attribute_index(index1);
1600 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1601 bool match_entry = compare_entry_to(k1, cp2, k2);
1602 bool match_operand = compare_operand_to(i1, cp2, i2);
1603 return (match_entry && match_operand);
1604 } break;
1605
1606 case JVM_CONSTANT_String:
1607 {
1608 Symbol* s1 = unresolved_string_at(index1);
1609 Symbol* s2 = cp2->unresolved_string_at(index2);
1610 if (s1 == s2) {
1611 return true;
1612 }
1613 } break;
1614
1615 case JVM_CONSTANT_Utf8:
1616 {
1617 Symbol* s1 = symbol_at(index1);
1618 Symbol* s2 = cp2->symbol_at(index2);
1619 if (s1 == s2) {
1620 return true;
1621 }
1622 } break;
1623
1624 // Invalid is used as the tag for the second constant pool entry
1625 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1626 // not be seen by itself.
1627 case JVM_CONSTANT_Invalid: // fall through
1628
1629 default:
1630 ShouldNotReachHere();
1631 break;
1632 }
1633
1634 return false;
1635 } // end compare_entry_to()
1636
1637
1638 // Resize the operands array with delta_len and delta_size.
1639 // Used in RedefineClasses for CP merge.
1640 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1641 int old_len = operand_array_length(operands());
1642 int new_len = old_len + delta_len;
1643 int min_len = (delta_len > 0) ? old_len : new_len;
1644
1645 int old_size = operands()->length();
1646 int new_size = old_size + delta_size;
1647 int min_size = (delta_size > 0) ? old_size : new_size;
1648
1649 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1650 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1651
1652 // Set index in the resized array for existing elements only
1653 for (int idx = 0; idx < min_len; idx++) {
1654 int offset = operand_offset_at(idx); // offset in original array
1655 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1656 }
1657 // Copy the bootstrap specifiers only
1658 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1659 new_ops->adr_at(2*new_len),
1660 (min_size - 2*min_len) * sizeof(u2));
1661 // Explicitly deallocate old operands array.
1662 // Note, it is not needed for 7u backport.
1663 if ( operands() != nullptr) { // the safety check
1664 MetadataFactory::free_array<u2>(loader_data, operands());
1665 }
1666 set_operands(new_ops);
1667 } // end resize_operands()
1668
1669
1670 // Extend the operands array with the length and size of the ext_cp operands.
1671 // Used in RedefineClasses for CP merge.
1672 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1673 int delta_len = operand_array_length(ext_cp->operands());
1674 if (delta_len == 0) {
1675 return; // nothing to do
1676 }
1677 int delta_size = ext_cp->operands()->length();
1678
1679 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1680
1681 if (operand_array_length(operands()) == 0) {
1682 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1683 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1684 // The first element index defines the offset of second part
1685 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1686 set_operands(new_ops);
1687 } else {
1688 resize_operands(delta_len, delta_size, CHECK);
1689 }
1690
1691 } // end extend_operands()
1692
1693
1694 // Shrink the operands array to a smaller array with new_len length.
1695 // Used in RedefineClasses for CP merge.
1696 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1697 int old_len = operand_array_length(operands());
1698 if (new_len == old_len) {
1699 return; // nothing to do
1700 }
1701 assert(new_len < old_len, "shrunken operands array must be smaller");
1702
1703 int free_base = operand_next_offset_at(new_len - 1);
1704 int delta_len = new_len - old_len;
1705 int delta_size = 2*delta_len + free_base - operands()->length();
1706
1707 resize_operands(delta_len, delta_size, CHECK);
1708
1709 } // end shrink_operands()
1710
1711
1712 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1713 const constantPoolHandle& to_cp,
1714 TRAPS) {
1715
1716 int from_oplen = operand_array_length(from_cp->operands());
1717 int old_oplen = operand_array_length(to_cp->operands());
1718 if (from_oplen != 0) {
1719 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1720 // append my operands to the target's operands array
1721 if (old_oplen == 0) {
1722 // Can't just reuse from_cp's operand list because of deallocation issues
1723 int len = from_cp->operands()->length();
1724 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1725 Copy::conjoint_memory_atomic(
1726 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1727 to_cp->set_operands(new_ops);
1728 } else {
1729 int old_len = to_cp->operands()->length();
1730 int from_len = from_cp->operands()->length();
1731 int old_off = old_oplen * sizeof(u2);
1732 int from_off = from_oplen * sizeof(u2);
1733 // Use the metaspace for the destination constant pool
1734 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1735 int fillp = 0, len = 0;
1736 // first part of dest
1737 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1738 new_operands->adr_at(fillp),
1739 (len = old_off) * sizeof(u2));
1740 fillp += len;
1741 // first part of src
1742 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1743 new_operands->adr_at(fillp),
1744 (len = from_off) * sizeof(u2));
1745 fillp += len;
1746 // second part of dest
1747 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1748 new_operands->adr_at(fillp),
1749 (len = old_len - old_off) * sizeof(u2));
1750 fillp += len;
1751 // second part of src
1752 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1753 new_operands->adr_at(fillp),
1754 (len = from_len - from_off) * sizeof(u2));
1755 fillp += len;
1756 assert(fillp == new_operands->length(), "");
1757
1758 // Adjust indexes in the first part of the copied operands array.
1759 for (int j = 0; j < from_oplen; j++) {
1760 int offset = operand_offset_at(new_operands, old_oplen + j);
1761 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1762 offset += old_len; // every new tuple is preceded by old_len extra u2's
1763 operand_offset_at_put(new_operands, old_oplen + j, offset);
1764 }
1765
1766 // replace target operands array with combined array
1767 to_cp->set_operands(new_operands);
1768 }
1769 }
1770 } // end copy_operands()
1771
1772
1773 // Copy this constant pool's entries at start_i to end_i (inclusive)
1774 // to the constant pool to_cp's entries starting at to_i. A total of
1775 // (end_i - start_i) + 1 entries are copied.
1776 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1777 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1778
1779
1780 int dest_cpi = to_i; // leave original alone for debug purposes
1781
1782 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1783 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1784
1785 switch (from_cp->tag_at(src_cpi).value()) {
1786 case JVM_CONSTANT_Double:
1787 case JVM_CONSTANT_Long:
1788 // double and long take two constant pool entries
1789 src_cpi += 2;
1790 dest_cpi += 2;
1791 break;
1792
1793 default:
1794 // all others take one constant pool entry
1795 src_cpi++;
1796 dest_cpi++;
1797 break;
1798 }
1799 }
1800 copy_operands(from_cp, to_cp, CHECK);
1801
1802 } // end copy_cp_to_impl()
1803
1804
1805 // Copy this constant pool's entry at from_i to the constant pool
1806 // to_cp's entry at to_i.
1807 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1808 const constantPoolHandle& to_cp, int to_i) {
1809
1810 int tag = from_cp->tag_at(from_i).value();
1811 switch (tag) {
1812 case JVM_CONSTANT_ClassIndex:
1813 {
1814 jint ki = from_cp->klass_index_at(from_i);
1815 to_cp->klass_index_at_put(to_i, ki);
1816 } break;
1817
1818 case JVM_CONSTANT_Double:
1819 {
1820 jdouble d = from_cp->double_at(from_i);
1821 to_cp->double_at_put(to_i, d);
1822 // double takes two constant pool entries so init second entry's tag
1823 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1824 } break;
1825
1826 case JVM_CONSTANT_Fieldref:
1827 {
1828 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1829 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1830 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1831 } break;
1832
1833 case JVM_CONSTANT_Float:
1834 {
1835 jfloat f = from_cp->float_at(from_i);
1836 to_cp->float_at_put(to_i, f);
1837 } break;
1838
1839 case JVM_CONSTANT_Integer:
1840 {
1841 jint i = from_cp->int_at(from_i);
1842 to_cp->int_at_put(to_i, i);
1843 } break;
1844
1845 case JVM_CONSTANT_InterfaceMethodref:
1846 {
1847 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1848 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1849 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1850 } break;
1851
1852 case JVM_CONSTANT_Long:
1853 {
1854 jlong l = from_cp->long_at(from_i);
1855 to_cp->long_at_put(to_i, l);
1856 // long takes two constant pool entries so init second entry's tag
1857 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1858 } break;
1859
1860 case JVM_CONSTANT_Methodref:
1861 {
1862 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1863 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1864 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1865 } break;
1866
1867 case JVM_CONSTANT_NameAndType:
1868 {
1869 int name_ref_index = from_cp->name_ref_index_at(from_i);
1870 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1871 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1872 } break;
1873
1874 case JVM_CONSTANT_StringIndex:
1875 {
1876 jint si = from_cp->string_index_at(from_i);
1877 to_cp->string_index_at_put(to_i, si);
1878 } break;
1879
1880 case JVM_CONSTANT_Class:
1881 case JVM_CONSTANT_UnresolvedClass:
1882 case JVM_CONSTANT_UnresolvedClassInError:
1883 {
1884 // Revert to JVM_CONSTANT_ClassIndex
1885 int name_index = from_cp->klass_slot_at(from_i).name_index();
1886 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1887 to_cp->klass_index_at_put(to_i, name_index);
1888 } break;
1889
1890 case JVM_CONSTANT_String:
1891 {
1892 Symbol* s = from_cp->unresolved_string_at(from_i);
1893 to_cp->unresolved_string_at_put(to_i, s);
1894 } break;
1895
1896 case JVM_CONSTANT_Utf8:
1897 {
1898 Symbol* s = from_cp->symbol_at(from_i);
1899 // Need to increase refcount, the old one will be thrown away and deferenced
1900 s->increment_refcount();
1901 to_cp->symbol_at_put(to_i, s);
1902 } break;
1903
1904 case JVM_CONSTANT_MethodType:
1905 case JVM_CONSTANT_MethodTypeInError:
1906 {
1907 jint k = from_cp->method_type_index_at(from_i);
1908 to_cp->method_type_index_at_put(to_i, k);
1909 } break;
1910
1911 case JVM_CONSTANT_MethodHandle:
1912 case JVM_CONSTANT_MethodHandleInError:
1913 {
1914 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1915 int k2 = from_cp->method_handle_index_at(from_i);
1916 to_cp->method_handle_index_at_put(to_i, k1, k2);
1917 } break;
1918
1919 case JVM_CONSTANT_Dynamic:
1920 case JVM_CONSTANT_DynamicInError:
1921 {
1922 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1923 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1924 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1925 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1926 } break;
1927
1928 case JVM_CONSTANT_InvokeDynamic:
1929 {
1930 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1931 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1932 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1933 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1934 } break;
1935
1936 // Invalid is used as the tag for the second constant pool entry
1937 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1938 // not be seen by itself.
1939 case JVM_CONSTANT_Invalid: // fall through
1940
1941 default:
1942 {
1943 ShouldNotReachHere();
1944 } break;
1945 }
1946 } // end copy_entry_to()
1947
1948 // Search constant pool search_cp for an entry that matches this
1949 // constant pool's entry at pattern_i. Returns the index of a
1950 // matching entry or zero (0) if there is no matching entry.
1951 int ConstantPool::find_matching_entry(int pattern_i,
1952 const constantPoolHandle& search_cp) {
1953
1954 // index zero (0) is not used
1955 for (int i = 1; i < search_cp->length(); i++) {
1956 bool found = compare_entry_to(pattern_i, search_cp, i);
1957 if (found) {
1958 return i;
1959 }
1960 }
1961
1962 return 0; // entry not found; return unused index zero (0)
1963 } // end find_matching_entry()
1964
1965
1966 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1967 // cp2's bootstrap specifier at idx2.
1968 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2) {
1969 BSMAttributeEntry* e1 = bsm_attribute_entry(idx1);
1970 BSMAttributeEntry* e2 = cp2->bsm_attribute_entry(idx2);
1971 int k1 = e1->bootstrap_method_index();
1972 int k2 = e2->bootstrap_method_index();
1973 bool match = compare_entry_to(k1, cp2, k2);
1974
1975 if (!match) {
1976 return false;
1977 }
1978 int argc = e1->argument_count();
1979 if (argc == e2->argument_count()) {
1980 for (int j = 0; j < argc; j++) {
1981 k1 = e1->argument_index(j);
1982 k2 = e2->argument_index(j);
1983 match = compare_entry_to(k1, cp2, k2);
1984 if (!match) {
1985 return false;
1986 }
1987 }
1988 return true; // got through loop; all elements equal
1989 }
1990 return false;
1991 } // end compare_operand_to()
1992
1993 // Search constant pool search_cp for a bootstrap specifier that matches
1994 // this constant pool's bootstrap specifier data at pattern_i index.
1995 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
1996 int ConstantPool::find_matching_operand(int pattern_i,
1997 const constantPoolHandle& search_cp, int search_len) {
1998 for (int i = 0; i < search_len; i++) {
1999 bool found = compare_operand_to(pattern_i, search_cp, i);
2000 if (found) {
2001 return i;
2002 }
2003 }
2004 return -1; // bootstrap specifier data not found; return unused index (-1)
2005 } // end find_matching_operand()
2006
2007
2008 #ifndef PRODUCT
2009
2010 const char* ConstantPool::printable_name_at(int cp_index) {
2011
2012 constantTag tag = tag_at(cp_index);
2013
2014 if (tag.is_string()) {
2015 return string_at_noresolve(cp_index);
2016 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
2017 return klass_name_at(cp_index)->as_C_string();
2018 } else if (tag.is_symbol()) {
2019 return symbol_at(cp_index)->as_C_string();
2020 }
2021 return "";
2022 }
2023
2024 #endif // PRODUCT
2025
2026
2027 // Returns size of constant pool entry.
2028 jint ConstantPool::cpool_entry_size(jint idx) {
2029 switch(tag_at(idx).value()) {
2030 case JVM_CONSTANT_Invalid:
2031 case JVM_CONSTANT_Unicode:
2032 return 1;
2033
2034 case JVM_CONSTANT_Utf8:
2035 return 3 + symbol_at(idx)->utf8_length();
2036
2037 case JVM_CONSTANT_Class:
2038 case JVM_CONSTANT_String:
2039 case JVM_CONSTANT_ClassIndex:
2040 case JVM_CONSTANT_UnresolvedClass:
2041 case JVM_CONSTANT_UnresolvedClassInError:
2042 case JVM_CONSTANT_StringIndex:
2043 case JVM_CONSTANT_MethodType:
2044 case JVM_CONSTANT_MethodTypeInError:
2045 return 3;
2046
2047 case JVM_CONSTANT_MethodHandle:
2048 case JVM_CONSTANT_MethodHandleInError:
2049 return 4; //tag, ref_kind, ref_index
2050
2051 case JVM_CONSTANT_Integer:
2052 case JVM_CONSTANT_Float:
2053 case JVM_CONSTANT_Fieldref:
2054 case JVM_CONSTANT_Methodref:
2055 case JVM_CONSTANT_InterfaceMethodref:
2056 case JVM_CONSTANT_NameAndType:
2057 return 5;
2058
2059 case JVM_CONSTANT_Dynamic:
2060 case JVM_CONSTANT_DynamicInError:
2061 case JVM_CONSTANT_InvokeDynamic:
2062 // u1 tag, u2 bsm, u2 nt
2063 return 5;
2064
2065 case JVM_CONSTANT_Long:
2066 case JVM_CONSTANT_Double:
2067 return 9;
2068 }
2069 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2070 return 1;
2071 } /* end cpool_entry_size */
2072
2073
2074 // SymbolHash is used to find a constant pool index from a string.
2075 // This function fills in SymbolHashs, one for utf8s and one for
2076 // class names, returns size of the cpool raw bytes.
2077 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
2078 SymbolHash *classmap) {
2079 jint size = 0;
2080
2081 for (u2 idx = 1; idx < length(); idx++) {
2082 u2 tag = tag_at(idx).value();
2083 size += cpool_entry_size(idx);
2084
2085 switch(tag) {
2086 case JVM_CONSTANT_Utf8: {
2087 Symbol* sym = symbol_at(idx);
2088 symmap->add_if_absent(sym, idx);
2089 break;
2090 }
2091 case JVM_CONSTANT_Class:
2092 case JVM_CONSTANT_UnresolvedClass:
2093 case JVM_CONSTANT_UnresolvedClassInError: {
2094 Symbol* sym = klass_name_at(idx);
2095 classmap->add_if_absent(sym, idx);
2096 break;
2097 }
2098 case JVM_CONSTANT_Long:
2099 case JVM_CONSTANT_Double: {
2100 idx++; // Both Long and Double take two cpool slots
2101 break;
2102 }
2103 }
2104 }
2105 return size;
2106 } /* end hash_utf8_entries_to */
2107
2108
2109 // Copy cpool bytes.
2110 // Returns:
2111 // 0, in case of OutOfMemoryError
2112 // -1, in case of internal error
2113 // > 0, count of the raw cpool bytes that have been copied
2114 int ConstantPool::copy_cpool_bytes(int cpool_size,
2115 SymbolHash* tbl,
2116 unsigned char *bytes) {
2117 u2 idx1, idx2;
2118 jint size = 0;
2119 jint cnt = length();
2120 unsigned char *start_bytes = bytes;
2121
2122 for (jint idx = 1; idx < cnt; idx++) {
2123 u1 tag = tag_at(idx).value();
2124 jint ent_size = cpool_entry_size(idx);
2125
2126 assert(size + ent_size <= cpool_size, "Size mismatch");
2127
2128 *bytes = tag;
2129 switch(tag) {
2130 case JVM_CONSTANT_Invalid: {
2131 break;
2132 }
2133 case JVM_CONSTANT_Unicode: {
2134 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2135 break;
2136 }
2137 case JVM_CONSTANT_Utf8: {
2138 Symbol* sym = symbol_at(idx);
2139 char* str = sym->as_utf8();
2140 // Warning! It's crashing on x86 with len = sym->utf8_length()
2141 int len = (int) strlen(str);
2142 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2143 for (int i = 0; i < len; i++) {
2144 bytes[3+i] = (u1) str[i];
2145 }
2146 break;
2147 }
2148 case JVM_CONSTANT_Integer: {
2149 jint val = int_at(idx);
2150 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2151 break;
2152 }
2153 case JVM_CONSTANT_Float: {
2154 jfloat val = float_at(idx);
2155 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2156 break;
2157 }
2158 case JVM_CONSTANT_Long: {
2159 jlong val = long_at(idx);
2160 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2161 idx++; // Long takes two cpool slots
2162 break;
2163 }
2164 case JVM_CONSTANT_Double: {
2165 jdouble val = double_at(idx);
2166 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2167 idx++; // Double takes two cpool slots
2168 break;
2169 }
2170 case JVM_CONSTANT_Class:
2171 case JVM_CONSTANT_UnresolvedClass:
2172 case JVM_CONSTANT_UnresolvedClassInError: {
2173 *bytes = JVM_CONSTANT_Class;
2174 Symbol* sym = klass_name_at(idx);
2175 idx1 = tbl->symbol_to_value(sym);
2176 assert(idx1 != 0, "Have not found a hashtable entry");
2177 Bytes::put_Java_u2((address) (bytes+1), idx1);
2178 break;
2179 }
2180 case JVM_CONSTANT_String: {
2181 *bytes = JVM_CONSTANT_String;
2182 Symbol* sym = unresolved_string_at(idx);
2183 idx1 = tbl->symbol_to_value(sym);
2184 assert(idx1 != 0, "Have not found a hashtable entry");
2185 Bytes::put_Java_u2((address) (bytes+1), idx1);
2186 break;
2187 }
2188 case JVM_CONSTANT_Fieldref:
2189 case JVM_CONSTANT_Methodref:
2190 case JVM_CONSTANT_InterfaceMethodref: {
2191 idx1 = uncached_klass_ref_index_at(idx);
2192 idx2 = uncached_name_and_type_ref_index_at(idx);
2193 Bytes::put_Java_u2((address) (bytes+1), idx1);
2194 Bytes::put_Java_u2((address) (bytes+3), idx2);
2195 break;
2196 }
2197 case JVM_CONSTANT_NameAndType: {
2198 idx1 = name_ref_index_at(idx);
2199 idx2 = signature_ref_index_at(idx);
2200 Bytes::put_Java_u2((address) (bytes+1), idx1);
2201 Bytes::put_Java_u2((address) (bytes+3), idx2);
2202 break;
2203 }
2204 case JVM_CONSTANT_ClassIndex: {
2205 *bytes = JVM_CONSTANT_Class;
2206 idx1 = checked_cast<u2>(klass_index_at(idx));
2207 Bytes::put_Java_u2((address) (bytes+1), idx1);
2208 break;
2209 }
2210 case JVM_CONSTANT_StringIndex: {
2211 *bytes = JVM_CONSTANT_String;
2212 idx1 = checked_cast<u2>(string_index_at(idx));
2213 Bytes::put_Java_u2((address) (bytes+1), idx1);
2214 break;
2215 }
2216 case JVM_CONSTANT_MethodHandle:
2217 case JVM_CONSTANT_MethodHandleInError: {
2218 *bytes = JVM_CONSTANT_MethodHandle;
2219 int kind = method_handle_ref_kind_at(idx);
2220 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2221 *(bytes+1) = (unsigned char) kind;
2222 Bytes::put_Java_u2((address) (bytes+2), idx1);
2223 break;
2224 }
2225 case JVM_CONSTANT_MethodType:
2226 case JVM_CONSTANT_MethodTypeInError: {
2227 *bytes = JVM_CONSTANT_MethodType;
2228 idx1 = checked_cast<u2>(method_type_index_at(idx));
2229 Bytes::put_Java_u2((address) (bytes+1), idx1);
2230 break;
2231 }
2232 case JVM_CONSTANT_Dynamic:
2233 case JVM_CONSTANT_DynamicInError: {
2234 *bytes = tag;
2235 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2236 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2237 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2238 Bytes::put_Java_u2((address) (bytes+1), idx1);
2239 Bytes::put_Java_u2((address) (bytes+3), idx2);
2240 break;
2241 }
2242 case JVM_CONSTANT_InvokeDynamic: {
2243 *bytes = tag;
2244 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2245 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2246 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2247 Bytes::put_Java_u2((address) (bytes+1), idx1);
2248 Bytes::put_Java_u2((address) (bytes+3), idx2);
2249 break;
2250 }
2251 }
2252 bytes += ent_size;
2253 size += ent_size;
2254 }
2255 assert(size == cpool_size, "Size mismatch");
2256
2257 return (int)(bytes - start_bytes);
2258 } /* end copy_cpool_bytes */
2259
2260 bool ConstantPool::is_maybe_on_stack() const {
2261 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2262 if (!Continuations::enabled()) {
2263 return false;
2264 }
2265
2266 // If the condition below is true, it means that the nmethod was found to
2267 // be alive the previous completed marking cycle.
2268 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2269 }
2270
2271 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2272 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2273 // memory for the method is reclaimed.
2274 bool ConstantPool::on_stack() const {
2275 if ((_flags &_on_stack) != 0) {
2276 return true;
2277 }
2278
2279 if (_cache == nullptr) {
2280 return false;
2281 }
2282
2283 return is_maybe_on_stack();
2284 }
2285
2286 void ConstantPool::set_on_stack(const bool value) {
2287 if (value) {
2288 // Only record if it's not already set.
2289 if (!on_stack()) {
2290 assert(!is_shared(), "should always be set for shared constant pools");
2291 _flags |= _on_stack;
2292 MetadataOnStackMark::record(this);
2293 }
2294 } else {
2295 // Clearing is done single-threadedly.
2296 if (!is_shared()) {
2297 _flags &= (u2)(~_on_stack);
2298 }
2299 }
2300 }
2301
2302 // Printing
2303
2304 void ConstantPool::print_on(outputStream* st) const {
2305 assert(is_constantPool(), "must be constantPool");
2306 st->print_cr("%s", internal_name());
2307 if (flags() != 0) {
2308 st->print(" - flags: 0x%x", flags());
2309 if (has_preresolution()) st->print(" has_preresolution");
2310 if (on_stack()) st->print(" on_stack");
2311 st->cr();
2312 }
2313 if (pool_holder() != nullptr) {
2314 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2315 }
2316 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2317 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2318 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2319 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2320 st->print_cr(" - cp length: %d", length());
2321
2322 for (int index = 1; index < length(); index++) { // Index 0 is unused
2323 ((ConstantPool*)this)->print_entry_on(index, st);
2324 switch (tag_at(index).value()) {
2325 case JVM_CONSTANT_Long :
2326 case JVM_CONSTANT_Double :
2327 index++; // Skip entry following eigth-byte constant
2328 }
2329
2330 }
2331 st->cr();
2332 }
2333
2334 // Print one constant pool entry
2335 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2336 EXCEPTION_MARK;
2337 st->print(" - %3d : ", cp_index);
2338 tag_at(cp_index).print_on(st);
2339 st->print(" : ");
2340 switch (tag_at(cp_index).value()) {
2341 case JVM_CONSTANT_Class :
2342 { Klass* k = klass_at(cp_index, CATCH);
2343 guarantee(k != nullptr, "need klass");
2344 k->print_value_on(st);
2345 st->print(" {" PTR_FORMAT "}", p2i(k));
2346 }
2347 break;
2348 case JVM_CONSTANT_Fieldref :
2349 case JVM_CONSTANT_Methodref :
2350 case JVM_CONSTANT_InterfaceMethodref :
2351 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2352 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2353 break;
2354 case JVM_CONSTANT_String :
2355 unresolved_string_at(cp_index)->print_value_on(st);
2356 break;
2357 case JVM_CONSTANT_Integer :
2358 st->print("%d", int_at(cp_index));
2359 break;
2360 case JVM_CONSTANT_Float :
2361 st->print("%f", float_at(cp_index));
2362 break;
2363 case JVM_CONSTANT_Long :
2364 st->print_jlong(long_at(cp_index));
2365 break;
2366 case JVM_CONSTANT_Double :
2367 st->print("%lf", double_at(cp_index));
2368 break;
2369 case JVM_CONSTANT_NameAndType :
2370 st->print("name_index=%d", name_ref_index_at(cp_index));
2371 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2372 break;
2373 case JVM_CONSTANT_Utf8 :
2374 symbol_at(cp_index)->print_value_on(st);
2375 break;
2376 case JVM_CONSTANT_ClassIndex: {
2377 int name_index = *int_at_addr(cp_index);
2378 st->print("klass_index=%d ", name_index);
2379 symbol_at(name_index)->print_value_on(st);
2380 }
2381 break;
2382 case JVM_CONSTANT_UnresolvedClass : // fall-through
2383 case JVM_CONSTANT_UnresolvedClassInError: {
2384 CPKlassSlot kslot = klass_slot_at(cp_index);
2385 int resolved_klass_index = kslot.resolved_klass_index();
2386 int name_index = kslot.name_index();
2387 assert(tag_at(name_index).is_symbol(), "sanity");
2388 symbol_at(name_index)->print_value_on(st);
2389 }
2390 break;
2391 case JVM_CONSTANT_MethodHandle :
2392 case JVM_CONSTANT_MethodHandleInError :
2393 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2394 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2395 break;
2396 case JVM_CONSTANT_MethodType :
2397 case JVM_CONSTANT_MethodTypeInError :
2398 st->print("signature_index=%d", method_type_index_at(cp_index));
2399 break;
2400 case JVM_CONSTANT_Dynamic :
2401 case JVM_CONSTANT_DynamicInError :
2402 {
2403 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2404 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2405 int argc = bootstrap_argument_count_at(cp_index);
2406 if (argc > 0) {
2407 for (int arg_i = 0; arg_i < argc; arg_i++) {
2408 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2409 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2410 }
2411 st->print("}");
2412 }
2413 }
2414 break;
2415 case JVM_CONSTANT_InvokeDynamic :
2416 {
2417 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2418 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2419 int argc = bootstrap_argument_count_at(cp_index);
2420 if (argc > 0) {
2421 for (int arg_i = 0; arg_i < argc; arg_i++) {
2422 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2423 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2424 }
2425 st->print("}");
2426 }
2427 }
2428 break;
2429 default:
2430 ShouldNotReachHere();
2431 break;
2432 }
2433 st->cr();
2434 }
2435
2436 void ConstantPool::print_value_on(outputStream* st) const {
2437 assert(is_constantPool(), "must be constantPool");
2438 st->print("constant pool [%d]", length());
2439 if (has_preresolution()) st->print("/preresolution");
2440 if (operands() != nullptr) st->print("/operands[%d]", operands()->length());
2441 print_address_on(st);
2442 if (pool_holder() != nullptr) {
2443 st->print(" for ");
2444 pool_holder()->print_value_on(st);
2445 bool extra = (pool_holder()->constants() != this);
2446 if (extra) st->print(" (extra)");
2447 }
2448 if (cache() != nullptr) {
2449 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2450 }
2451 }
2452
2453 // Verification
2454
2455 void ConstantPool::verify_on(outputStream* st) {
2456 guarantee(is_constantPool(), "object must be constant pool");
2457 for (int i = 0; i< length(); i++) {
2458 constantTag tag = tag_at(i);
2459 if (tag.is_klass() || tag.is_unresolved_klass()) {
2460 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2461 } else if (tag.is_symbol()) {
2462 Symbol* entry = symbol_at(i);
2463 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2464 } else if (tag.is_string()) {
2465 Symbol* entry = unresolved_string_at(i);
2466 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2467 }
2468 }
2469 if (pool_holder() != nullptr) {
2470 // Note: pool_holder() can be null in temporary constant pools
2471 // used during constant pool merging
2472 guarantee(pool_holder()->is_klass(), "should be klass");
2473 }
2474 }