1 /*
2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "cds/archiveHeapWriter.hpp"
27 #include "cds/archiveHeapLoader.hpp"
28 #include "cds/archiveBuilder.hpp"
29 #include "cds/cdsConfig.hpp"
30 #include "cds/classPrelinker.hpp"
31 #include "cds/lambdaFormInvokers.inline.hpp"
32 #include "cds/heapShared.hpp"
33 #include "classfile/classLoader.hpp"
34 #include "classfile/classLoaderData.hpp"
35 #include "classfile/javaClasses.inline.hpp"
36 #include "classfile/metadataOnStackMark.hpp"
37 #include "classfile/stringTable.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/vmClasses.hpp"
41 #include "classfile/vmSymbols.hpp"
42 #include "code/codeCache.hpp"
43 #include "interpreter/bootstrapInfo.hpp"
44 #include "interpreter/linkResolver.hpp"
45 #include "jvm.h"
46 #include "logging/log.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/allocation.inline.hpp"
49 #include "memory/metadataFactory.hpp"
50 #include "memory/metaspaceClosure.hpp"
51 #include "memory/oopFactory.hpp"
52 #include "memory/resourceArea.hpp"
53 #include "memory/universe.hpp"
54 #include "oops/array.hpp"
55 #include "oops/constantPool.inline.hpp"
56 #include "oops/cpCache.inline.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/typeArrayOop.inline.hpp"
63 #include "prims/jvmtiExport.hpp"
64 #include "runtime/atomic.hpp"
65 //#include "runtime/fieldDescriptor.inline.hpp"
66 #include "runtime/handles.inline.hpp"
67 #include "runtime/init.hpp"
68 #include "runtime/javaCalls.hpp"
69 #include "runtime/javaThread.inline.hpp"
70 #include "runtime/perfData.hpp"
71 #include "runtime/signature.hpp"
72 #include "runtime/vframe.inline.hpp"
73 #include "utilities/checkedCast.hpp"
74 #include "utilities/copy.hpp"
75
76 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
77 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
78 int size = ConstantPool::size(length);
79 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
80 }
81
82 void ConstantPool::copy_fields(const ConstantPool* orig) {
83 // Preserve dynamic constant information from the original pool
84 if (orig->has_dynamic_constant()) {
85 set_has_dynamic_constant();
86 }
87
88 set_major_version(orig->major_version());
89 set_minor_version(orig->minor_version());
90
91 set_source_file_name_index(orig->source_file_name_index());
92 set_generic_signature_index(orig->generic_signature_index());
93 }
94
95 #ifdef ASSERT
96
97 // MetaspaceObj allocation invariant is calloc equivalent memory
98 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
99 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
100 assert(tags != nullptr, "invariant");
101 const int length = tags->length();
102 for (int index = 0; index < length; ++index) {
103 if (JVM_CONSTANT_Invalid != tags->at(index)) {
104 return false;
105 }
106 }
107 return true;
108 }
109
110 #endif
111
112 ConstantPool::ConstantPool() {
113 assert(CDSConfig::is_dumping_static_archive() || UseSharedSpaces, "only for CDS");
114 }
115
116 ConstantPool::ConstantPool(Array<u1>* tags) :
117 _tags(tags),
118 _length(tags->length()) {
119
120 assert(_tags != nullptr, "invariant");
121 assert(tags->length() == _length, "invariant");
122 assert(tag_array_is_zero_initialized(tags), "invariant");
123 assert(0 == flags(), "invariant");
124 assert(0 == version(), "invariant");
125 assert(nullptr == _pool_holder, "invariant");
126 }
127
128 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
129 if (cache() != nullptr) {
130 MetadataFactory::free_metadata(loader_data, cache());
131 set_cache(nullptr);
132 }
133
134 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
135 set_resolved_klasses(nullptr);
136
137 MetadataFactory::free_array<jushort>(loader_data, operands());
138 set_operands(nullptr);
139
140 release_C_heap_structures();
141
142 // free tag array
143 MetadataFactory::free_array<u1>(loader_data, tags());
144 set_tags(nullptr);
145 }
146
147 void ConstantPool::release_C_heap_structures() {
148 // walk constant pool and decrement symbol reference counts
149 unreference_symbols();
150 }
151
152 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
153 log_trace(cds)("Iter(ConstantPool): %p", this);
154
155 it->push(&_tags, MetaspaceClosure::_writable);
156 it->push(&_cache);
157 it->push(&_pool_holder);
158 it->push(&_operands);
159 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
160
161 for (int i = 0; i < length(); i++) {
162 // The only MSO's embedded in the CP entries are Symbols:
163 // JVM_CONSTANT_String
164 // JVM_CONSTANT_Utf8
165 constantTag ctag = tag_at(i);
166 if (ctag.is_string() || ctag.is_utf8()) {
167 it->push(symbol_at_addr(i));
168 }
169 }
170 }
171
172 objArrayOop ConstantPool::resolved_references() const {
173 return _cache->resolved_references();
174 }
175
176 // Called from outside constant pool resolution where a resolved_reference array
177 // may not be present.
178 objArrayOop ConstantPool::resolved_references_or_null() const {
179 if (_cache == nullptr) {
180 return nullptr;
181 } else {
182 return _cache->resolved_references();
183 }
184 }
185
186 oop ConstantPool::resolved_reference_at(int index) const {
187 oop result = resolved_references()->obj_at(index);
188 assert(oopDesc::is_oop_or_null(result), "Must be oop");
189 return result;
190 }
191
192 // Use a CAS for multithreaded access
193 oop ConstantPool::set_resolved_reference_at(int index, oop new_result) {
194 assert(oopDesc::is_oop_or_null(new_result), "Must be oop");
195 return resolved_references()->replace_if_null(index, new_result);
196 }
197
198 // Create resolved_references array and mapping array for original cp indexes
199 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
200 // to map it back for resolving and some unlikely miscellaneous uses.
201 // The objects created by invokedynamic are appended to this list.
202 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
203 const intStack& reference_map,
204 int constant_pool_map_length,
205 TRAPS) {
206 // Initialized the resolved object cache.
207 int map_length = reference_map.length();
208 if (map_length > 0) {
209 // Only need mapping back to constant pool entries. The map isn't used for
210 // invokedynamic resolved_reference entries. For invokedynamic entries,
211 // the constant pool cache index has the mapping back to both the constant
212 // pool and to the resolved reference index.
213 if (constant_pool_map_length > 0) {
214 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
215
216 for (int i = 0; i < constant_pool_map_length; i++) {
217 int x = reference_map.at(i);
218 assert(x == (int)(jushort) x, "klass index is too big");
219 om->at_put(i, (jushort)x);
220 }
221 set_reference_map(om);
222 }
223
224 // Create Java array for holding resolved strings, methodHandles,
225 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
226 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
227 HandleMark hm(THREAD);
228 Handle refs_handle (THREAD, stom); // must handleize.
229 set_resolved_references(loader_data->add_handle(refs_handle));
230
231 // Create a "scratch" copy of the resolved references array to archive
232 if (CDSConfig::is_dumping_heap()) {
233 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
234 HeapShared::add_scratch_resolved_references(this, scratch_references);
235 }
236 }
237 }
238
239 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
240 // A ConstantPool can't possibly have 0xffff valid class entries,
241 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
242 // entry for the class's name. So at most we will have 0xfffe class entries.
243 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
244 // UnresolvedKlass entries that are temporarily created during class redefinition.
245 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
246 assert(resolved_klasses() == nullptr, "sanity");
247 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
248 set_resolved_klasses(rk);
249 }
250
251 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
252 int len = length();
253 int num_klasses = 0;
254 for (int i = 1; i <len; i++) {
255 switch (tag_at(i).value()) {
256 case JVM_CONSTANT_ClassIndex:
257 {
258 const int class_index = klass_index_at(i);
259 unresolved_klass_at_put(i, class_index, num_klasses++);
260 }
261 break;
262 #ifndef PRODUCT
263 case JVM_CONSTANT_Class:
264 case JVM_CONSTANT_UnresolvedClass:
265 case JVM_CONSTANT_UnresolvedClassInError:
266 // All of these should have been reverted back to ClassIndex before calling
267 // this function.
268 ShouldNotReachHere();
269 #endif
270 }
271 }
272 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
273 }
274
275 // Hidden class support:
276 void ConstantPool::klass_at_put(int class_index, Klass* k) {
277 assert(k != nullptr, "must be valid klass");
278 CPKlassSlot kslot = klass_slot_at(class_index);
279 int resolved_klass_index = kslot.resolved_klass_index();
280 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
281 Atomic::release_store(adr, k);
282
283 // The interpreter assumes when the tag is stored, the klass is resolved
284 // and the Klass* non-null, so we need hardware store ordering here.
285 release_tag_at_put(class_index, JVM_CONSTANT_Class);
286 }
287
288 #if INCLUDE_CDS_JAVA_HEAP
289 // Returns the _resolved_reference array after removing unarchivable items from it.
290 // Returns null if this class is not supported, or _resolved_reference doesn't exist.
291 objArrayOop ConstantPool::prepare_resolved_references_for_archiving() {
292 if (_cache == nullptr) {
293 return nullptr; // nothing to do
294 }
295
296 InstanceKlass *ik = pool_holder();
297 if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
298 ik->is_shared_app_class())) {
299 // Archiving resolved references for classes from non-builtin loaders
300 // is not yet supported.
301 return nullptr;
302 }
303
304 objArrayOop rr = resolved_references();
305 if (rr != nullptr) {
306 ResourceMark rm;
307 int rr_len = rr->length();
308 GrowableArray<bool> keep_resolved_refs(rr_len, rr_len, false);
309 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
310
311 if (cache() != nullptr && ArchiveInvokeDynamic) {
312 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
313 if (indy_entries != nullptr) {
314 for (int i = 0; i < indy_entries->length(); i++) {
315 ResolvedIndyEntry *rie = indy_entries->adr_at(i);
316 if (rie->is_resolved() && ClassPrelinker::is_resolution_deterministic(src_cp, rie->constant_pool_index())) {
317 int rr_index = rie->resolved_references_index();
318 keep_resolved_refs.at_put(rr_index, true);
319 }
320 }
321 }
322
323 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
324 if (method_entries != nullptr) {
325 for (int i = 0; i < method_entries->length(); i++) {
326 ResolvedMethodEntry* rme = method_entries->adr_at(i);
327 if (rme->is_resolved(Bytecodes::_invokehandle) && rme->has_appendix() &&
328 can_archive_resolved_method(rme)) {
329 int rr_index = rme->resolved_references_index();
330 keep_resolved_refs.at_put(rr_index, true);
331 }
332 }
333 }
334 }
335
336 objArrayOop scratch_rr = HeapShared::scratch_resolved_references(src_cp);
337 Array<u2>* ref_map = reference_map();
338 int ref_map_len = ref_map == nullptr ? 0 : ref_map->length();
339 for (int i = 0; i < rr_len; i++) {
340 oop obj = rr->obj_at(i);
341 scratch_rr->obj_at_put(i, nullptr);
342 if (obj != nullptr) {
343 if (i < ref_map_len) {
344 int index = object_to_cp_index(i);
345 if (tag_at(index).is_string()) {
346 assert(java_lang_String::is_instance(obj), "must be");
347 if (!ArchiveHeapWriter::is_string_too_large_to_archive(obj)) {
348 scratch_rr->obj_at_put(i, obj);
349 }
350 }
351 } else if (keep_resolved_refs.at(i)) {
352 scratch_rr->obj_at_put(i, obj);
353 }
354 }
355 }
356 return scratch_rr;
357 }
358 return rr;
359 }
360
361 void ConstantPool::add_dumped_interned_strings() {
362 objArrayOop rr = resolved_references();
363 if (rr != nullptr) {
364 int rr_len = rr->length();
365 for (int i = 0; i < rr_len; i++) {
366 oop p = rr->obj_at(i);
367 if (java_lang_String::is_instance(p) &&
368 !ArchiveHeapWriter::is_string_too_large_to_archive(p)) {
369 HeapShared::add_to_dumped_interned_strings(p);
370 }
371 }
372 }
373 }
374 #endif
375
376 #if INCLUDE_CDS
377 // CDS support. Create a new resolved_references array.
378 void ConstantPool::restore_unshareable_info(TRAPS) {
379 if (!_pool_holder->is_linked() && !_pool_holder->is_rewritten()) {
380 return;
381 }
382 assert(is_constantPool(), "ensure C++ vtable is restored");
383 assert(on_stack(), "should always be set for shared constant pools");
384 assert(is_shared(), "should always be set for shared constant pools");
385 if (is_for_method_handle_intrinsic()) {
386 return;
387 }
388 assert(_cache != nullptr, "constant pool _cache should not be null");
389
390 // Only create the new resolved references array if it hasn't been attempted before
391 if (resolved_references() != nullptr) return;
392
393 if (vmClasses::Object_klass_loaded()) {
394 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
395 #if INCLUDE_CDS_JAVA_HEAP
396 if (ArchiveHeapLoader::is_in_use() &&
397 _cache->archived_references() != nullptr) {
398 oop archived = _cache->archived_references();
399 // Create handle for the archived resolved reference array object
400 HandleMark hm(THREAD);
401 Handle refs_handle(THREAD, archived);
402 set_resolved_references(loader_data->add_handle(refs_handle));
403 _cache->clear_archived_references();
404 } else
405 #endif
406 {
407 // No mapped archived resolved reference array
408 // Recreate the object array and add to ClassLoaderData.
409 int map_length = resolved_reference_length();
410 if (map_length > 0) {
411 objArrayOop stom = oopFactory::new_objArray(vmClasses::Object_klass(), map_length, CHECK);
412 HandleMark hm(THREAD);
413 Handle refs_handle(THREAD, stom); // must handleize.
414 set_resolved_references(loader_data->add_handle(refs_handle));
415 }
416 }
417 }
418
419 if (CDSConfig::is_dumping_final_static_archive() && resolved_references() != nullptr) {
420 objArrayOop scratch_references = oopFactory::new_objArray(vmClasses::Object_klass(), resolved_references()->length(), CHECK);
421 HeapShared::add_scratch_resolved_references(this, scratch_references);
422 }
423 }
424
425 void ConstantPool::remove_unshareable_info() {
426 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
427 // The _on_stack flag is used to prevent ConstantPools from deallocation during
428 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
429 // we always set _on_stack to true to avoid having to change _flags during runtime.
430 _flags |= (_on_stack | _is_shared);
431
432 if (!ArchiveBuilder::current()->get_source_addr(_pool_holder)->is_linked()) {
433 return;
434 }
435
436 if (is_for_method_handle_intrinsic()) {
437 // This CP was created by Method::make_method_handle_intrinsic() and has nothing
438 // that need to be removed/restored. It has no cpCache since the intrinsic methods
439 // don't have any bytecodes.
440 assert(cache() == NULL, "must not have cpCache");
441 return;
442 }
443
444 // Resolved references are not in the shared archive.
445 // Save the length for restoration. It is not necessarily the same length
446 // as reference_map.length() if invokedynamic is saved. It is needed when
447 // re-creating the resolved reference array if archived heap data cannot be map
448 // at runtime.
449 set_resolved_reference_length(
450 resolved_references() != nullptr ? resolved_references()->length() : 0);
451 set_resolved_references(OopHandle());
452
453 remove_unshareable_entries();
454 }
455
456 static const char* get_type(Klass* k) {
457 const char* type;
458 Klass* src_k;
459 if (ArchiveBuilder::is_active() && ArchiveBuilder::current()->is_in_buffer_space(k)) {
460 src_k = ArchiveBuilder::current()->get_source_addr(k);
461 } else {
462 src_k = k;
463 }
464
465 if (src_k->is_objArray_klass()) {
466 src_k = ObjArrayKlass::cast(src_k)->bottom_klass();
467 assert(!src_k->is_objArray_klass(), "sanity");
468 }
469
470 if (src_k->is_typeArray_klass()) {
471 type = "prim";
472 } else {
473 InstanceKlass* src_ik = InstanceKlass::cast(src_k);
474 oop loader = src_ik->class_loader();
475 if (loader == nullptr) {
476 type = "boot";
477 } else if (loader == SystemDictionary::java_platform_loader()) {
478 type = "plat";
479 } else if (loader == SystemDictionary::java_system_loader()) {
480 type = "app";
481 } else {
482 type = "unreg";
483 }
484 }
485
486 return type;
487 }
488
489 void ConstantPool::remove_unshareable_entries() {
490 ResourceMark rm;
491 log_info(cds, resolve)("Archiving CP entries for %s", pool_holder()->name()->as_C_string());
492 for (int cp_index = 1; cp_index < length(); cp_index++) { // cp_index 0 is unused
493 int cp_tag = tag_at(cp_index).value();
494 switch (cp_tag) {
495 case JVM_CONSTANT_UnresolvedClass:
496 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false);
497 break;
498 case JVM_CONSTANT_UnresolvedClassInError:
499 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
500 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(false);
501 break;
502 case JVM_CONSTANT_MethodHandleInError:
503 tag_at_put(cp_index, JVM_CONSTANT_MethodHandle);
504 break;
505 case JVM_CONSTANT_MethodTypeInError:
506 tag_at_put(cp_index, JVM_CONSTANT_MethodType);
507 break;
508 case JVM_CONSTANT_DynamicInError:
509 tag_at_put(cp_index, JVM_CONSTANT_Dynamic);
510 break;
511 case JVM_CONSTANT_Class:
512 remove_resolved_klass_if_non_deterministic(cp_index);
513 break;
514 default:
515 break;
516 }
517 }
518
519 if (cache() != nullptr) {
520 // cache() is null if this class is not yet linked.
521 remove_resolved_field_entries_if_non_deterministic();
522 remove_resolved_method_entries_if_non_deterministic();
523 remove_resolved_indy_entries_if_non_deterministic();
524 }
525 }
526
527 void ConstantPool::remove_resolved_klass_if_non_deterministic(int cp_index) {
528 assert(ArchiveBuilder::current()->is_in_buffer_space(this), "must be");
529 assert(tag_at(cp_index).is_klass(), "must be resolved");
530
531 // k could be null if the referenced class has been excluded via
532 // SystemDictionaryShared::is_excluded_class().
533 Klass* k = resolved_klass_at(cp_index);
534 bool revert = true;
535 if (k != nullptr) {
536 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
537 if (ClassPrelinker::is_resolution_deterministic(src_cp, cp_index)) {
538 revert = false;
539 }
540 }
541
542 if (revert) {
543 // This resolved klass entry cannot be archived. Revert the tag to UnresolvedClass,
544 // so that it will be resolved at runtime.
545 int resolved_klass_index = klass_slot_at(cp_index).resolved_klass_index();
546 resolved_klasses()->at_put(resolved_klass_index, nullptr);
547 tag_at_put(cp_index, JVM_CONSTANT_UnresolvedClass);
548 }
549
550 LogStreamHandle(Trace, cds, resolve) log;
551 if (log.is_enabled()) {
552 ResourceMark rm;
553 log.print("%s klass CP entry [%3d]: %s %s",
554 (revert ? "reverted" : "archived"),
555 cp_index, pool_holder()->name()->as_C_string(), get_type(pool_holder()));
556 if (revert) {
557 Symbol* name = klass_name_at(cp_index);
558 log.print(" \"%s\"", name->as_C_string());
559 } else {
560 log.print(" => %s %s%s", k->name()->as_C_string(), get_type(k),
561 (!k->is_instance_klass() || pool_holder()->is_subtype_of(k)) ? "" : " (not supertype)");
562 }
563 }
564 ArchiveBuilder::alloc_stats()->record_klass_cp_entry(!revert);
565 }
566
567 void ConstantPool::remove_resolved_field_entries_if_non_deterministic() {
568 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
569 Array<ResolvedFieldEntry>* field_entries = cache()->resolved_field_entries();
570 if (field_entries != nullptr) {
571 for (int i = 0; i < field_entries->length(); i++) {
572 ResolvedFieldEntry* rfi = field_entries->adr_at(i);
573 int cp_index = rfi->constant_pool_index();
574 bool archived = false;
575 bool resolved = rfi->is_resolved(Bytecodes::_getstatic) ||
576 rfi->is_resolved(Bytecodes::_putstatic) ||
577 rfi->is_resolved(Bytecodes::_putfield) ||
578 rfi->is_resolved(Bytecodes::_putfield);
579 if (resolved && ClassPrelinker::is_resolution_deterministic(src_cp, cp_index)) {
580 rfi->mark_and_relocate();
581 archived = true;
582 } else {
583 rfi->remove_unshareable_info();
584 }
585 if (resolved) {
586 LogStreamHandle(Trace, cds, resolve) log;
587 if (log.is_enabled()) {
588 ResourceMark rm;
589 int klass_cp_index = uncached_klass_ref_index_at(cp_index);
590 Symbol* klass_name = klass_name_at(klass_cp_index);
591 Symbol* name = uncached_name_ref_at(cp_index);
592 Symbol* signature = uncached_signature_ref_at(cp_index);
593 log.print("%s field CP entry [%3d]: %s %s %s.%s:%s",
594 (archived ? "archived" : "excluded"),
595 cp_index,
596 pool_holder()->name()->as_C_string(),
597 (archived ? "=>" : " "),
598 klass_name->as_C_string(), name->as_C_string(), signature->as_C_string());
599 }
600 }
601 ArchiveBuilder::alloc_stats()->record_field_cp_entry(archived, resolved && !archived);
602 }
603 }
604 }
605
606 void ConstantPool::remove_resolved_method_entries_if_non_deterministic() {
607 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
608 Array<ResolvedMethodEntry>* method_entries = cache()->resolved_method_entries();
609 if (method_entries != nullptr) {
610 for (int i = 0; i < method_entries->length(); i++) {
611 ResolvedMethodEntry* rme = method_entries->adr_at(i);
612 int cp_index = rme->constant_pool_index();
613 bool archived = false;
614 bool resolved = rme->is_resolved(Bytecodes::_invokevirtual) ||
615 rme->is_resolved(Bytecodes::_invokespecial) ||
616 rme->is_resolved(Bytecodes::_invokestatic) ||
617 rme->is_resolved(Bytecodes::_invokeinterface) ||
618 rme->is_resolved(Bytecodes::_invokehandle);
619 if (resolved && can_archive_resolved_method(rme)) {
620 rme->mark_and_relocate(src_cp);
621 archived = true;
622 } else {
623 rme->remove_unshareable_info();
624 }
625 if (resolved) {
626 LogStreamHandle(Trace, cds, resolve) log;
627 if (log.is_enabled()) {
628 ResourceMark rm;
629 int klass_cp_index = uncached_klass_ref_index_at(cp_index);
630 Symbol* klass_name = klass_name_at(klass_cp_index);
631 Symbol* name = uncached_name_ref_at(cp_index);
632 Symbol* signature = uncached_signature_ref_at(cp_index);
633 log.print("%s%s method CP entry [%3d]: %s %s.%s:%s",
634 (archived ? "archived" : "excluded"),
635 (rme->is_resolved(Bytecodes::_invokeinterface) ? " interface" : ""),
636 cp_index,
637 pool_holder()->name()->as_C_string(),
638 klass_name->as_C_string(), name->as_C_string(), signature->as_C_string());
639 if (archived) {
640 Klass* resolved_klass = resolved_klass_at(klass_cp_index);
641 log.print(" => %s%s",
642 resolved_klass->name()->as_C_string(),
643 (rme->is_resolved(Bytecodes::_invokestatic) ? " *** static" : ""));
644 }
645 }
646 }
647 ArchiveBuilder::alloc_stats()->record_method_cp_entry(archived, resolved && !archived);
648 }
649 }
650 }
651
652 void ConstantPool::remove_resolved_indy_entries_if_non_deterministic() {
653 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
654 Array<ResolvedIndyEntry>* indy_entries = cache()->resolved_indy_entries();
655 if (indy_entries != nullptr) {
656 for (int i = 0; i < indy_entries->length(); i++) {
657 ResolvedIndyEntry* rei = indy_entries->adr_at(i);
658 int cp_index = rei->constant_pool_index();
659 bool archived = false;
660 bool resolved = rei->is_resolved();
661 if (resolved && ClassPrelinker::is_resolution_deterministic(src_cp, cp_index)) {
662 rei->mark_and_relocate();
663 archived = true;
664 } else {
665 rei->remove_unshareable_info();
666 }
667 if (resolved) {
668 LogStreamHandle(Trace, cds, resolve) log;
669 if (log.is_enabled()) {
670 ResourceMark rm;
671 int bsm = bootstrap_method_ref_index_at(cp_index);
672 int bsm_ref = method_handle_index_at(bsm);
673 Symbol* bsm_name = uncached_name_ref_at(bsm_ref);
674 Symbol* bsm_signature = uncached_signature_ref_at(bsm_ref);
675 Symbol* bsm_klass = klass_name_at(uncached_klass_ref_index_at(bsm_ref));
676 log.print("%s indy CP entry [%3d]: %s (%d)",
677 (archived ? "archived" : "excluded"),
678 cp_index, pool_holder()->name()->as_C_string(), i);
679 log.print(" %s %s.%s:%s", (archived ? "=>" : " "), bsm_klass->as_C_string(), bsm_name->as_C_string(), bsm_signature->as_C_string());
680 }
681 }
682 ArchiveBuilder::alloc_stats()->record_indy_cp_entry(archived, resolved && !archived);
683 }
684 }
685 }
686
687 bool ConstantPool::can_archive_invokehandle(ResolvedMethodEntry* rme) {
688 assert(rme->is_resolved(Bytecodes::_invokehandle), "sanity");
689
690 int cp_index = rme->constant_pool_index();
691 int klass_cp_index = uncached_klass_ref_index_at(cp_index);
692 Klass* resolved_klass = resolved_klass_at(klass_cp_index);
693 if (!resolved_klass->is_instance_klass()) {
694 // FIXME: can this ever happen?
695 return false;
696 }
697 // FIXME -- any class referenced by the archived CP entries should be added to ArchiveBuilder::classes, or should be
698 // filtered out.
699 return true;
700 }
701
702 bool ConstantPool::can_archive_resolved_method(ResolvedMethodEntry* method_entry) {
703 if (!(pool_holder()->is_shared_boot_class() || pool_holder()->is_shared_platform_class() ||
704 pool_holder()->is_shared_app_class())) {
705 // Archiving resolved cp entries for classes from non-builtin loaders
706 // is not yet supported.
707 return false;
708 }
709
710 if (CDSConfig::is_dumping_dynamic_archive()) {
711 // InstanceKlass::methods() is has been resorted. We need to
712 // update the vtable_index in method_entry (not implemented)
713 return false;
714 }
715
716 if (!method_entry->is_resolved(Bytecodes::_invokevirtual)) {
717 if (method_entry->method() == nullptr) {
718 return false;
719 }
720 if (method_entry->method()->is_continuation_native_intrinsic()) {
721 return false; // FIXME: corresponding stub is generated on demand during method resolution (see LinkResolver::resolve_static_call).
722 }
723 }
724
725 int cp_index = method_entry->constant_pool_index();
726 ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(this);
727 assert(src_cp->tag_at(cp_index).is_method() || src_cp->tag_at(cp_index).is_interface_method(), "sanity");
728
729 if (!ClassPrelinker::is_resolution_deterministic(src_cp, cp_index)) {
730 return false;
731 }
732
733 if (method_entry->is_resolved(Bytecodes::_invokehandle)) {
734 if (!ArchiveInvokeDynamic) {
735 // invokehandle depends on archived MethodType and LambdaForms.
736 return false;
737 } else if (!can_archive_invokehandle(method_entry)) {
738 return false;
739 }
740 } else if (method_entry->is_resolved(Bytecodes::_invokestatic) ||
741 method_entry->is_resolved(Bytecodes::_invokeinterface) ||
742 method_entry->is_resolved(Bytecodes::_invokevirtual) ||
743 method_entry->is_resolved(Bytecodes::_invokespecial)) {
744 // OK
745 } else {
746 return false; // just to be safe.
747 }
748
749 return true;
750 }
751 #endif // INCLUDE_CDS
752
753 int ConstantPool::cp_to_object_index(int cp_index) {
754 // this is harder don't do this so much.
755 int i = reference_map()->find(checked_cast<u2>(cp_index));
756 // We might not find the index for jsr292 call.
757 return (i < 0) ? _no_index_sentinel : i;
758 }
759
760 void ConstantPool::string_at_put(int obj_index, oop str) {
761 oop result = set_resolved_reference_at(obj_index, str);
762 assert(result == nullptr || result == str, "Only set once or to the same string.");
763 }
764
765 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
766 ResourceMark rm;
767 int line_number = -1;
768 const char * source_file = nullptr;
769 if (JavaThread::current()->has_last_Java_frame()) {
770 // try to identify the method which called this function.
771 vframeStream vfst(JavaThread::current());
772 if (!vfst.at_end()) {
773 line_number = vfst.method()->line_number_from_bci(vfst.bci());
774 Symbol* s = vfst.method()->method_holder()->source_file_name();
775 if (s != nullptr) {
776 source_file = s->as_C_string();
777 }
778 }
779 }
780 if (k != this_cp->pool_holder()) {
781 // only print something if the classes are different
782 if (source_file != nullptr) {
783 log_debug(class, resolve)("%s %s %s:%d",
784 this_cp->pool_holder()->external_name(),
785 k->external_name(), source_file, line_number);
786 } else {
787 log_debug(class, resolve)("%s %s",
788 this_cp->pool_holder()->external_name(),
789 k->external_name());
790 }
791 }
792 }
793
794 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int cp_index,
795 TRAPS) {
796 JavaThread* javaThread = THREAD;
797
798 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
799 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
800 // the entry and tag is not updated atomically.
801 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
802 int resolved_klass_index = kslot.resolved_klass_index();
803 int name_index = kslot.name_index();
804 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
805
806 // The tag must be JVM_CONSTANT_Class in order to read the correct value from
807 // the unresolved_klasses() array.
808 if (this_cp->tag_at(cp_index).is_klass()) {
809 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
810 if (klass != nullptr) {
811 return klass;
812 }
813 }
814
815 // This tag doesn't change back to unresolved class unless at a safepoint.
816 if (this_cp->tag_at(cp_index).is_unresolved_klass_in_error()) {
817 // The original attempt to resolve this constant pool entry failed so find the
818 // class of the original error and throw another error of the same class
819 // (JVMS 5.4.3).
820 // If there is a detail message, pass that detail message to the error.
821 // The JVMS does not strictly require us to duplicate the same detail message,
822 // or any internal exception fields such as cause or stacktrace. But since the
823 // detail message is often a class name or other literal string, we will repeat it
824 // if we can find it in the symbol table.
825 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
826 ShouldNotReachHere();
827 }
828
829 HandleMark hm(THREAD);
830 Handle mirror_handle;
831 Symbol* name = this_cp->symbol_at(name_index);
832 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
833 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
834
835 Klass* k;
836 {
837 // Turn off the single stepping while doing class resolution
838 JvmtiHideSingleStepping jhss(javaThread);
839 k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
840 } // JvmtiHideSingleStepping jhss(javaThread);
841
842 if (!HAS_PENDING_EXCEPTION) {
843 // preserve the resolved klass from unloading
844 mirror_handle = Handle(THREAD, k->java_mirror());
845 // Do access check for klasses
846 verify_constant_pool_resolve(this_cp, k, THREAD);
847 }
848
849 // Failed to resolve class. We must record the errors so that subsequent attempts
850 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
851 if (HAS_PENDING_EXCEPTION) {
852 save_and_throw_exception(this_cp, cp_index, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
853 // If CHECK_NULL above doesn't return the exception, that means that
854 // some other thread has beaten us and has resolved the class.
855 // To preserve old behavior, we return the resolved class.
856 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
857 assert(klass != nullptr, "must be resolved if exception was cleared");
858 return klass;
859 }
860
861 // logging for class+resolve.
862 if (log_is_enabled(Debug, class, resolve)){
863 trace_class_resolution(this_cp, k);
864 }
865
866 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
867 Atomic::release_store(adr, k);
868 // The interpreter assumes when the tag is stored, the klass is resolved
869 // and the Klass* stored in _resolved_klasses is non-null, so we need
870 // hardware store ordering here.
871 // We also need to CAS to not overwrite an error from a racing thread.
872
873 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
874 (jbyte)JVM_CONSTANT_UnresolvedClass,
875 (jbyte)JVM_CONSTANT_Class);
876
877 // We need to recheck exceptions from racing thread and return the same.
878 if (old_tag == JVM_CONSTANT_UnresolvedClassInError) {
879 // Remove klass.
880 this_cp->resolved_klasses()->at_put(resolved_klass_index, nullptr);
881 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
882 }
883
884 return k;
885 }
886
887
888 // Does not update ConstantPool* - to avoid any exception throwing. Used
889 // by compiler and exception handling. Also used to avoid classloads for
890 // instanceof operations. Returns null if the class has not been loaded or
891 // if the verification of constant pool failed
892 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
893 CPKlassSlot kslot = this_cp->klass_slot_at(which);
894 int resolved_klass_index = kslot.resolved_klass_index();
895 int name_index = kslot.name_index();
896 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
897
898 if (this_cp->tag_at(which).is_klass()) {
899 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
900 assert(k != nullptr, "should be resolved");
901 return k;
902 } else if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
903 return nullptr;
904 } else {
905 Thread* current = Thread::current();
906 HandleMark hm(current);
907 Symbol* name = this_cp->symbol_at(name_index);
908 oop loader = this_cp->pool_holder()->class_loader();
909 oop protection_domain = this_cp->pool_holder()->protection_domain();
910 Handle h_prot (current, protection_domain);
911 Handle h_loader (current, loader);
912 Klass* k = SystemDictionary::find_instance_klass(current, name, h_loader, h_prot);
913
914 // Avoid constant pool verification at a safepoint, as it takes the Module_lock.
915 if (k != nullptr && current->is_Java_thread()) {
916 // Make sure that resolving is legal
917 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
918 ExceptionMark em(THREAD);
919 // return null if verification fails
920 verify_constant_pool_resolve(this_cp, k, THREAD);
921 if (HAS_PENDING_EXCEPTION) {
922 CLEAR_PENDING_EXCEPTION;
923 return nullptr;
924 }
925 return k;
926 } else {
927 return k;
928 }
929 }
930 }
931
932 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
933 int which) {
934 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
935 if (!(which >= 0 && which < cpool->resolved_method_entries_length())) {
936 // FIXME: should be an assert
937 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
938 return nullptr;
939 }
940 return cpool->cache()->method_if_resolved(which);
941 }
942
943
944 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
945 if (cpool->cache() == nullptr) return false; // nothing to load yet
946 if (code == Bytecodes::_invokedynamic) {
947 return cpool->resolved_indy_entry_at(which)->has_appendix();
948 } else {
949 return cpool->resolved_method_entry_at(which)->has_appendix();
950 }
951 }
952
953 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
954 if (cpool->cache() == nullptr) return nullptr; // nothing to load yet
955 if (code == Bytecodes::_invokedynamic) {
956 return cpool->resolved_reference_from_indy(which);
957 } else {
958 return cpool->cache()->appendix_if_resolved(which);
959 }
960 }
961
962
963 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which, Bytecodes::Code code) {
964 if (cpool->cache() == nullptr) return false; // nothing to load yet
965 if (code == Bytecodes::_invokedynamic) {
966 return cpool->resolved_indy_entry_at(which)->has_local_signature();
967 } else {
968 return cpool->resolved_method_entry_at(which)->has_local_signature();
969 }
970 }
971
972 // Translate index, which could be CPCache index or Indy index, to a constant pool index
973 int ConstantPool::to_cp_index(int index, Bytecodes::Code code) {
974 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
975 switch(code) {
976 case Bytecodes::_invokedynamic:
977 return invokedynamic_bootstrap_ref_index_at(index);
978 case Bytecodes::_getfield:
979 case Bytecodes::_getstatic:
980 case Bytecodes::_putfield:
981 case Bytecodes::_putstatic:
982 return resolved_field_entry_at(index)->constant_pool_index();
983 case Bytecodes::_invokeinterface:
984 case Bytecodes::_invokehandle:
985 case Bytecodes::_invokespecial:
986 case Bytecodes::_invokestatic:
987 case Bytecodes::_invokevirtual:
988 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
989 return resolved_method_entry_at(index)->constant_pool_index();
990 default:
991 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
992 }
993 }
994
995 bool ConstantPool::is_resolved(int index, Bytecodes::Code code) {
996 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
997 switch(code) {
998 case Bytecodes::_invokedynamic:
999 return resolved_indy_entry_at(index)->is_resolved();
1000
1001 case Bytecodes::_getfield:
1002 case Bytecodes::_getstatic:
1003 case Bytecodes::_putfield:
1004 case Bytecodes::_putstatic:
1005 return resolved_field_entry_at(index)->is_resolved(code);
1006
1007 case Bytecodes::_invokeinterface:
1008 case Bytecodes::_invokehandle:
1009 case Bytecodes::_invokespecial:
1010 case Bytecodes::_invokestatic:
1011 case Bytecodes::_invokevirtual:
1012 case Bytecodes::_fast_invokevfinal: // Bytecode interpreter uses this
1013 return resolved_method_entry_at(index)->is_resolved(code);
1014
1015 default:
1016 fatal("Unexpected bytecode: %s", Bytecodes::name(code));
1017 }
1018 }
1019
1020 u2 ConstantPool::uncached_name_and_type_ref_index_at(int cp_index) {
1021 if (tag_at(cp_index).has_bootstrap()) {
1022 u2 pool_index = bootstrap_name_and_type_ref_index_at(cp_index);
1023 assert(tag_at(pool_index).is_name_and_type(), "");
1024 return pool_index;
1025 }
1026 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
1027 assert(!tag_at(cp_index).has_bootstrap(), "Must be handled above");
1028 jint ref_index = *int_at_addr(cp_index);
1029 return extract_high_short_from_int(ref_index);
1030 }
1031
1032 u2 ConstantPool::name_and_type_ref_index_at(int index, Bytecodes::Code code) {
1033 return uncached_name_and_type_ref_index_at(to_cp_index(index, code));
1034 }
1035
1036 constantTag ConstantPool::tag_ref_at(int which, Bytecodes::Code code) {
1037 // which may be either a Constant Pool index or a rewritten index
1038 int pool_index = which;
1039 assert(cache() != nullptr, "'index' is a rewritten index so this class must have been rewritten");
1040 pool_index = to_cp_index(which, code);
1041 return tag_at(pool_index);
1042 }
1043
1044 u2 ConstantPool::uncached_klass_ref_index_at(int cp_index) {
1045 assert(tag_at(cp_index).is_field_or_method(), "Corrupted constant pool");
1046 jint ref_index = *int_at_addr(cp_index);
1047 return extract_low_short_from_int(ref_index);
1048 }
1049
1050 u2 ConstantPool::klass_ref_index_at(int index, Bytecodes::Code code) {
1051 assert(code != Bytecodes::_invokedynamic,
1052 "an invokedynamic instruction does not have a klass");
1053 return uncached_klass_ref_index_at(to_cp_index(index, code));
1054 }
1055
1056 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
1057 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
1058 return; // short cut, typeArray klass is always accessible
1059 }
1060 Klass* holder = this_cp->pool_holder();
1061 LinkResolver::check_klass_accessibility(holder, k, CHECK);
1062 }
1063
1064
1065 u2 ConstantPool::name_ref_index_at(int cp_index) {
1066 jint ref_index = name_and_type_at(cp_index);
1067 return extract_low_short_from_int(ref_index);
1068 }
1069
1070
1071 u2 ConstantPool::signature_ref_index_at(int cp_index) {
1072 jint ref_index = name_and_type_at(cp_index);
1073 return extract_high_short_from_int(ref_index);
1074 }
1075
1076
1077 Klass* ConstantPool::klass_ref_at(int which, Bytecodes::Code code, TRAPS) {
1078 return klass_at(klass_ref_index_at(which, code), THREAD);
1079 }
1080
1081 Symbol* ConstantPool::klass_name_at(int cp_index) const {
1082 return symbol_at(klass_slot_at(cp_index).name_index());
1083 }
1084
1085 Symbol* ConstantPool::klass_ref_at_noresolve(int which, Bytecodes::Code code) {
1086 jint ref_index = klass_ref_index_at(which, code);
1087 return klass_at_noresolve(ref_index);
1088 }
1089
1090 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int cp_index) {
1091 jint ref_index = uncached_klass_ref_index_at(cp_index);
1092 return klass_at_noresolve(ref_index);
1093 }
1094
1095 char* ConstantPool::string_at_noresolve(int cp_index) {
1096 return unresolved_string_at(cp_index)->as_C_string();
1097 }
1098
1099 BasicType ConstantPool::basic_type_for_signature_at(int cp_index) const {
1100 return Signature::basic_type(symbol_at(cp_index));
1101 }
1102
1103
1104 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
1105 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
1106 if (this_cp->tag_at(index).is_string()) {
1107 this_cp->string_at(index, CHECK);
1108 }
1109 }
1110 }
1111
1112 static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
1113 // Note: caller needs ResourceMark
1114
1115 // Dig out the detailed message to reuse if possible
1116 const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
1117 if (msg != nullptr) {
1118 return msg;
1119 }
1120
1121 Symbol* message = nullptr;
1122 // Return specific message for the tag
1123 switch (tag.value()) {
1124 case JVM_CONSTANT_UnresolvedClass:
1125 // return the class name in the error message
1126 message = this_cp->klass_name_at(which);
1127 break;
1128 case JVM_CONSTANT_MethodHandle:
1129 // return the method handle name in the error message
1130 message = this_cp->method_handle_name_ref_at(which);
1131 break;
1132 case JVM_CONSTANT_MethodType:
1133 // return the method type signature in the error message
1134 message = this_cp->method_type_signature_at(which);
1135 break;
1136 case JVM_CONSTANT_Dynamic:
1137 // return the name of the condy in the error message
1138 message = this_cp->uncached_name_ref_at(which);
1139 break;
1140 default:
1141 ShouldNotReachHere();
1142 }
1143
1144 return message != nullptr ? message->as_C_string() : nullptr;
1145 }
1146
1147 static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
1148 constantTag tag, oop pending_exception) {
1149
1150 ResourceMark rm(current);
1151 Symbol* error = pending_exception->klass()->name();
1152 oop cause = java_lang_Throwable::cause(pending_exception);
1153
1154 // Also dig out the exception cause, if present.
1155 Symbol* cause_sym = nullptr;
1156 const char* cause_msg = nullptr;
1157 if (cause != nullptr && cause != pending_exception) {
1158 cause_sym = cause->klass()->name();
1159 cause_msg = java_lang_Throwable::message_as_utf8(cause);
1160 }
1161
1162 const char* message = exception_message(this_cp, which, tag, pending_exception);
1163 SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
1164 }
1165
1166
1167 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
1168 ResourceMark rm(THREAD);
1169 const char* message = nullptr;
1170 Symbol* cause = nullptr;
1171 const char* cause_msg = nullptr;
1172 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
1173 assert(error != nullptr, "checking");
1174
1175 CLEAR_PENDING_EXCEPTION;
1176 if (message != nullptr) {
1177 if (cause != nullptr) {
1178 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1179 THROW_MSG_CAUSE(error, message, h_cause);
1180 } else {
1181 THROW_MSG(error, message);
1182 }
1183 } else {
1184 if (cause != nullptr) {
1185 Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
1186 THROW_CAUSE(error, h_cause);
1187 } else {
1188 THROW(error);
1189 }
1190 }
1191 }
1192
1193 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
1194 // exception in the resolution error table, so that the same exception is thrown again.
1195 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int cp_index,
1196 constantTag tag, TRAPS) {
1197
1198 int error_tag = tag.error_value();
1199
1200 if (!PENDING_EXCEPTION->
1201 is_a(vmClasses::LinkageError_klass())) {
1202 // Just throw the exception and don't prevent these classes from
1203 // being loaded due to virtual machine errors like StackOverflow
1204 // and OutOfMemoryError, etc, or if the thread was hit by stop()
1205 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
1206 } else if (this_cp->tag_at(cp_index).value() != error_tag) {
1207 add_resolution_error(THREAD, this_cp, cp_index, tag, PENDING_EXCEPTION);
1208 // CAS in the tag. If a thread beat us to registering this error that's fine.
1209 // If another thread resolved the reference, this is a race condition. This
1210 // thread may have had a security manager or something temporary.
1211 // This doesn't deterministically get an error. So why do we save this?
1212 // We save this because jvmti can add classes to the bootclass path after
1213 // this error, so it needs to get the same error if the error is first.
1214 jbyte old_tag = Atomic::cmpxchg((jbyte*)this_cp->tag_addr_at(cp_index),
1215 (jbyte)tag.value(),
1216 (jbyte)error_tag);
1217 if (old_tag != error_tag && old_tag != tag.value()) {
1218 // MethodHandles and MethodType doesn't change to resolved version.
1219 assert(this_cp->tag_at(cp_index).is_klass(), "Wrong tag value");
1220 // Forget the exception and use the resolved class.
1221 CLEAR_PENDING_EXCEPTION;
1222 }
1223 } else {
1224 // some other thread put this in error state
1225 throw_resolution_error(this_cp, cp_index, CHECK);
1226 }
1227 }
1228
1229 constantTag ConstantPool::constant_tag_at(int cp_index) {
1230 constantTag tag = tag_at(cp_index);
1231 if (tag.is_dynamic_constant()) {
1232 BasicType bt = basic_type_for_constant_at(cp_index);
1233 return constantTag(constantTag::type2tag(bt));
1234 }
1235 return tag;
1236 }
1237
1238 BasicType ConstantPool::basic_type_for_constant_at(int cp_index) {
1239 constantTag tag = tag_at(cp_index);
1240 if (tag.is_dynamic_constant() ||
1241 tag.is_dynamic_constant_in_error()) {
1242 // have to look at the signature for this one
1243 Symbol* constant_type = uncached_signature_ref_at(cp_index);
1244 return Signature::basic_type(constant_type);
1245 }
1246 return tag.basic_type();
1247 }
1248
1249 // Called to resolve constants in the constant pool and return an oop.
1250 // Some constant pool entries cache their resolved oop. This is also
1251 // called to create oops from constants to use in arguments for invokedynamic
1252 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
1253 int cp_index, int cache_index,
1254 bool* status_return, TRAPS) {
1255 oop result_oop = nullptr;
1256
1257 if (cache_index == _possible_index_sentinel) {
1258 // It is possible that this constant is one which is cached in the objects.
1259 // We'll do a linear search. This should be OK because this usage is rare.
1260 // FIXME: If bootstrap specifiers stress this code, consider putting in
1261 // a reverse index. Binary search over a short array should do it.
1262 assert(cp_index > 0, "valid constant pool index");
1263 cache_index = this_cp->cp_to_object_index(cp_index);
1264 }
1265 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
1266 assert(cp_index == _no_index_sentinel || cp_index >= 0, "");
1267
1268 if (cache_index >= 0) {
1269 result_oop = this_cp->resolved_reference_at(cache_index);
1270 if (result_oop != nullptr) {
1271 if (result_oop == Universe::the_null_sentinel()) {
1272 DEBUG_ONLY(int temp_index = (cp_index >= 0 ? cp_index : this_cp->object_to_cp_index(cache_index)));
1273 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
1274 result_oop = nullptr;
1275 }
1276 if (status_return != nullptr) (*status_return) = true;
1277 return result_oop;
1278 // That was easy...
1279 }
1280 cp_index = this_cp->object_to_cp_index(cache_index);
1281 }
1282
1283 jvalue prim_value; // temp used only in a few cases below
1284
1285 constantTag tag = this_cp->tag_at(cp_index);
1286
1287 if (status_return != nullptr) {
1288 // don't trigger resolution if the constant might need it
1289 switch (tag.value()) {
1290 case JVM_CONSTANT_Class:
1291 {
1292 CPKlassSlot kslot = this_cp->klass_slot_at(cp_index);
1293 int resolved_klass_index = kslot.resolved_klass_index();
1294 if (this_cp->resolved_klasses()->at(resolved_klass_index) == nullptr) {
1295 (*status_return) = false;
1296 return nullptr;
1297 }
1298 // the klass is waiting in the CP; go get it
1299 break;
1300 }
1301 case JVM_CONSTANT_String:
1302 case JVM_CONSTANT_Integer:
1303 case JVM_CONSTANT_Float:
1304 case JVM_CONSTANT_Long:
1305 case JVM_CONSTANT_Double:
1306 // these guys trigger OOM at worst
1307 break;
1308 default:
1309 (*status_return) = false;
1310 return nullptr;
1311 }
1312 // from now on there is either success or an OOME
1313 (*status_return) = true;
1314 }
1315
1316 switch (tag.value()) {
1317
1318 case JVM_CONSTANT_UnresolvedClass:
1319 case JVM_CONSTANT_Class:
1320 {
1321 assert(cache_index == _no_index_sentinel, "should not have been set");
1322 Klass* resolved = klass_at_impl(this_cp, cp_index, CHECK_NULL);
1323 // ldc wants the java mirror.
1324 result_oop = resolved->java_mirror();
1325 break;
1326 }
1327
1328 case JVM_CONSTANT_Dynamic:
1329 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_invokedynamic_time(),
1330 ClassLoader::perf_resolve_invokedynamic_count(),
1331 THREAD->class_being_initialized() == nullptr);
1332 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
1333 BootstrapInfo bootstrap_specifier(this_cp, cp_index);
1334
1335 // The initial step in resolving an unresolved symbolic reference to a
1336 // dynamically-computed constant is to resolve the symbolic reference to a
1337 // method handle which will be the bootstrap method for the dynamically-computed
1338 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
1339 // method fails, then a MethodHandleInError is stored at the corresponding
1340 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
1341 // set a DynamicConstantInError here since any subsequent use of this
1342 // bootstrap method will encounter the resolution of MethodHandleInError.
1343 // Both the first, (resolution of the BSM and its static arguments), and the second tasks,
1344 // (invocation of the BSM), of JVMS Section 5.4.3.6 occur within invoke_bootstrap_method()
1345 // for the bootstrap_specifier created above.
1346 SystemDictionary::invoke_bootstrap_method(bootstrap_specifier, THREAD);
1347 Exceptions::wrap_dynamic_exception(/* is_indy */ false, THREAD);
1348 if (HAS_PENDING_EXCEPTION) {
1349 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
1350 // will check for a LinkageError and store a DynamicConstantInError.
1351 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1352 }
1353 result_oop = bootstrap_specifier.resolved_value()();
1354 BasicType type = Signature::basic_type(bootstrap_specifier.signature());
1355 if (!is_reference_type(type)) {
1356 // Make sure the primitive value is properly boxed.
1357 // This is a JDK responsibility.
1358 const char* fail = nullptr;
1359 if (result_oop == nullptr) {
1360 fail = "null result instead of box";
1361 } else if (!is_java_primitive(type)) {
1362 // FIXME: support value types via unboxing
1363 fail = "can only handle references and primitives";
1364 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
1365 fail = "primitive is not properly boxed";
1366 }
1367 if (fail != nullptr) {
1368 // Since this exception is not a LinkageError, throw exception
1369 // but do not save a DynamicInError resolution result.
1370 // See section 5.4.3 of the VM spec.
1371 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1372 }
1373 }
1374
1375 LogTarget(Debug, methodhandles, condy) lt_condy;
1376 if (lt_condy.is_enabled()) {
1377 LogStream ls(lt_condy);
1378 bootstrap_specifier.print_msg_on(&ls, "resolve_constant_at_impl");
1379 }
1380 break;
1381 }
1382
1383 case JVM_CONSTANT_String:
1384 assert(cache_index != _no_index_sentinel, "should have been set");
1385 result_oop = string_at_impl(this_cp, cp_index, cache_index, CHECK_NULL);
1386 break;
1387
1388 case JVM_CONSTANT_MethodHandle:
1389 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_handle_time(),
1390 ClassLoader::perf_resolve_method_handle_count(),
1391 THREAD->class_being_initialized() == nullptr);
1392 int ref_kind = this_cp->method_handle_ref_kind_at(cp_index);
1393 int callee_index = this_cp->method_handle_klass_index_at(cp_index);
1394 Symbol* name = this_cp->method_handle_name_ref_at(cp_index);
1395 Symbol* signature = this_cp->method_handle_signature_ref_at(cp_index);
1396 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(cp_index));
1397 { ResourceMark rm(THREAD);
1398 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1399 ref_kind, cp_index, this_cp->method_handle_index_at(cp_index),
1400 callee_index, name->as_C_string(), signature->as_C_string());
1401 }
1402
1403 Klass* callee = klass_at_impl(this_cp, callee_index, THREAD);
1404 if (HAS_PENDING_EXCEPTION) {
1405 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1406 }
1407
1408 // Check constant pool method consistency
1409 if ((callee->is_interface() && m_tag.is_method()) ||
1410 (!callee->is_interface() && m_tag.is_interface_method())) {
1411 ResourceMark rm(THREAD);
1412 stringStream ss;
1413 ss.print("Inconsistent constant pool data in classfile for class %s. "
1414 "Method '", callee->name()->as_C_string());
1415 signature->print_as_signature_external_return_type(&ss);
1416 ss.print(" %s(", name->as_C_string());
1417 signature->print_as_signature_external_parameters(&ss);
1418 ss.print(")' at index %d is %s and should be %s",
1419 cp_index,
1420 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1421 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1422 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), "%s", ss.as_string());
1423 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1424 }
1425
1426 Klass* klass = this_cp->pool_holder();
1427 HandleMark hm(THREAD);
1428 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1429 callee, name, signature,
1430 THREAD);
1431 if (HAS_PENDING_EXCEPTION) {
1432 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1433 }
1434 result_oop = value();
1435 break;
1436 }
1437
1438 case JVM_CONSTANT_MethodType:
1439 { PerfTraceTimedEvent timer(ClassLoader::perf_resolve_method_type_time(),
1440 ClassLoader::perf_resolve_method_type_count(),
1441 THREAD->class_being_initialized() == nullptr);
1442 Symbol* signature = this_cp->method_type_signature_at(cp_index);
1443 { ResourceMark rm(THREAD);
1444 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1445 cp_index, this_cp->method_type_index_at(cp_index),
1446 signature->as_C_string());
1447 }
1448 Klass* klass = this_cp->pool_holder();
1449 HandleMark hm(THREAD);
1450 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1451 result_oop = value();
1452 if (HAS_PENDING_EXCEPTION) {
1453 save_and_throw_exception(this_cp, cp_index, tag, CHECK_NULL);
1454 }
1455 break;
1456 }
1457
1458 case JVM_CONSTANT_Integer:
1459 assert(cache_index == _no_index_sentinel, "should not have been set");
1460 prim_value.i = this_cp->int_at(cp_index);
1461 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1462 break;
1463
1464 case JVM_CONSTANT_Float:
1465 assert(cache_index == _no_index_sentinel, "should not have been set");
1466 prim_value.f = this_cp->float_at(cp_index);
1467 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1468 break;
1469
1470 case JVM_CONSTANT_Long:
1471 assert(cache_index == _no_index_sentinel, "should not have been set");
1472 prim_value.j = this_cp->long_at(cp_index);
1473 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1474 break;
1475
1476 case JVM_CONSTANT_Double:
1477 assert(cache_index == _no_index_sentinel, "should not have been set");
1478 prim_value.d = this_cp->double_at(cp_index);
1479 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1480 break;
1481
1482 case JVM_CONSTANT_UnresolvedClassInError:
1483 case JVM_CONSTANT_DynamicInError:
1484 case JVM_CONSTANT_MethodHandleInError:
1485 case JVM_CONSTANT_MethodTypeInError:
1486 throw_resolution_error(this_cp, cp_index, CHECK_NULL);
1487 break;
1488
1489 default:
1490 fatal("unexpected constant tag at CP %p[%d/%d] = %d", this_cp(), cp_index, cache_index, tag.value());
1491 break;
1492 }
1493
1494 if (cache_index >= 0) {
1495 // Benign race condition: resolved_references may already be filled in.
1496 // The important thing here is that all threads pick up the same result.
1497 // It doesn't matter which racing thread wins, as long as only one
1498 // result is used by all threads, and all future queries.
1499 oop new_result = (result_oop == nullptr ? Universe::the_null_sentinel() : result_oop);
1500 oop old_result = this_cp->set_resolved_reference_at(cache_index, new_result);
1501 if (old_result == nullptr) {
1502 return result_oop; // was installed
1503 } else {
1504 // Return the winning thread's result. This can be different than
1505 // the result here for MethodHandles.
1506 if (old_result == Universe::the_null_sentinel())
1507 old_result = nullptr;
1508 return old_result;
1509 }
1510 } else {
1511 assert(result_oop != Universe::the_null_sentinel(), "");
1512 return result_oop;
1513 }
1514 }
1515
1516 oop ConstantPool::uncached_string_at(int cp_index, TRAPS) {
1517 Symbol* sym = unresolved_string_at(cp_index);
1518 oop str = StringTable::intern(sym, CHECK_(nullptr));
1519 assert(java_lang_String::is_instance(str), "must be string");
1520 return str;
1521 }
1522
1523 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int cp_index,
1524 int start_arg, int end_arg,
1525 objArrayHandle info, int pos,
1526 bool must_resolve, Handle if_not_available,
1527 TRAPS) {
1528 int limit = pos + end_arg - start_arg;
1529 // checks: cp_index in range [0..this_cp->length),
1530 // tag at cp_index, start..end in range [0..this_cp->bootstrap_argument_count],
1531 // info array non-null, pos..limit in [0..info.length]
1532 if ((0 >= cp_index || cp_index >= this_cp->length()) ||
1533 !(this_cp->tag_at(cp_index).is_invoke_dynamic() ||
1534 this_cp->tag_at(cp_index).is_dynamic_constant()) ||
1535 (0 > start_arg || start_arg > end_arg) ||
1536 (end_arg > this_cp->bootstrap_argument_count_at(cp_index)) ||
1537 (0 > pos || pos > limit) ||
1538 (info.is_null() || limit > info->length())) {
1539 // An index or something else went wrong; throw an error.
1540 // Since this is an internal API, we don't expect this,
1541 // so we don't bother to craft a nice message.
1542 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1543 }
1544 // now we can loop safely
1545 int info_i = pos;
1546 for (int i = start_arg; i < end_arg; i++) {
1547 int arg_index = this_cp->bootstrap_argument_index_at(cp_index, i);
1548 oop arg_oop;
1549 if (must_resolve) {
1550 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1551 } else {
1552 bool found_it = false;
1553 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1554 if (!found_it) arg_oop = if_not_available();
1555 }
1556 info->obj_at_put(info_i++, arg_oop);
1557 }
1558 }
1559
1560 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int cp_index, int obj_index, TRAPS) {
1561 // If the string has already been interned, this entry will be non-null
1562 oop str = this_cp->resolved_reference_at(obj_index);
1563 assert(str != Universe::the_null_sentinel(), "");
1564 if (str != nullptr) return str;
1565 Symbol* sym = this_cp->unresolved_string_at(cp_index);
1566 str = StringTable::intern(sym, CHECK_(nullptr));
1567 this_cp->string_at_put(obj_index, str);
1568 assert(java_lang_String::is_instance(str), "must be string");
1569 return str;
1570 }
1571
1572
1573 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int cp_index) {
1574 // Names are interned, so we can compare Symbol*s directly
1575 Symbol* cp_name = klass_name_at(cp_index);
1576 return (cp_name == k->name());
1577 }
1578
1579
1580 // Iterate over symbols and decrement ones which are Symbol*s
1581 // This is done during GC.
1582 // Only decrement the UTF8 symbols. Strings point to
1583 // these symbols but didn't increment the reference count.
1584 void ConstantPool::unreference_symbols() {
1585 for (int index = 1; index < length(); index++) { // Index 0 is unused
1586 constantTag tag = tag_at(index);
1587 if (tag.is_symbol()) {
1588 symbol_at(index)->decrement_refcount();
1589 }
1590 }
1591 }
1592
1593
1594 // Compare this constant pool's entry at index1 to the constant pool
1595 // cp2's entry at index2.
1596 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1597 int index2) {
1598
1599 // The error tags are equivalent to non-error tags when comparing
1600 jbyte t1 = tag_at(index1).non_error_value();
1601 jbyte t2 = cp2->tag_at(index2).non_error_value();
1602
1603 // Some classes are pre-resolved (like Throwable) which may lead to
1604 // consider it as a different entry. We then revert them back temporarily
1605 // to ensure proper comparison.
1606 if (t1 == JVM_CONSTANT_Class) {
1607 t1 = JVM_CONSTANT_UnresolvedClass;
1608 }
1609 if (t2 == JVM_CONSTANT_Class) {
1610 t2 = JVM_CONSTANT_UnresolvedClass;
1611 }
1612
1613 if (t1 != t2) {
1614 // Not the same entry type so there is nothing else to check. Note
1615 // that this style of checking will consider resolved/unresolved
1616 // class pairs as different.
1617 // From the ConstantPool* API point of view, this is correct
1618 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1619 // plays out in the context of ConstantPool* merging.
1620 return false;
1621 }
1622
1623 switch (t1) {
1624 case JVM_CONSTANT_ClassIndex:
1625 {
1626 int recur1 = klass_index_at(index1);
1627 int recur2 = cp2->klass_index_at(index2);
1628 if (compare_entry_to(recur1, cp2, recur2)) {
1629 return true;
1630 }
1631 } break;
1632
1633 case JVM_CONSTANT_Double:
1634 {
1635 jdouble d1 = double_at(index1);
1636 jdouble d2 = cp2->double_at(index2);
1637 if (d1 == d2) {
1638 return true;
1639 }
1640 } break;
1641
1642 case JVM_CONSTANT_Fieldref:
1643 case JVM_CONSTANT_InterfaceMethodref:
1644 case JVM_CONSTANT_Methodref:
1645 {
1646 int recur1 = uncached_klass_ref_index_at(index1);
1647 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1648 bool match = compare_entry_to(recur1, cp2, recur2);
1649 if (match) {
1650 recur1 = uncached_name_and_type_ref_index_at(index1);
1651 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1652 if (compare_entry_to(recur1, cp2, recur2)) {
1653 return true;
1654 }
1655 }
1656 } break;
1657
1658 case JVM_CONSTANT_Float:
1659 {
1660 jfloat f1 = float_at(index1);
1661 jfloat f2 = cp2->float_at(index2);
1662 if (f1 == f2) {
1663 return true;
1664 }
1665 } break;
1666
1667 case JVM_CONSTANT_Integer:
1668 {
1669 jint i1 = int_at(index1);
1670 jint i2 = cp2->int_at(index2);
1671 if (i1 == i2) {
1672 return true;
1673 }
1674 } break;
1675
1676 case JVM_CONSTANT_Long:
1677 {
1678 jlong l1 = long_at(index1);
1679 jlong l2 = cp2->long_at(index2);
1680 if (l1 == l2) {
1681 return true;
1682 }
1683 } break;
1684
1685 case JVM_CONSTANT_NameAndType:
1686 {
1687 int recur1 = name_ref_index_at(index1);
1688 int recur2 = cp2->name_ref_index_at(index2);
1689 if (compare_entry_to(recur1, cp2, recur2)) {
1690 recur1 = signature_ref_index_at(index1);
1691 recur2 = cp2->signature_ref_index_at(index2);
1692 if (compare_entry_to(recur1, cp2, recur2)) {
1693 return true;
1694 }
1695 }
1696 } break;
1697
1698 case JVM_CONSTANT_StringIndex:
1699 {
1700 int recur1 = string_index_at(index1);
1701 int recur2 = cp2->string_index_at(index2);
1702 if (compare_entry_to(recur1, cp2, recur2)) {
1703 return true;
1704 }
1705 } break;
1706
1707 case JVM_CONSTANT_UnresolvedClass:
1708 {
1709 Symbol* k1 = klass_name_at(index1);
1710 Symbol* k2 = cp2->klass_name_at(index2);
1711 if (k1 == k2) {
1712 return true;
1713 }
1714 } break;
1715
1716 case JVM_CONSTANT_MethodType:
1717 {
1718 int k1 = method_type_index_at(index1);
1719 int k2 = cp2->method_type_index_at(index2);
1720 if (compare_entry_to(k1, cp2, k2)) {
1721 return true;
1722 }
1723 } break;
1724
1725 case JVM_CONSTANT_MethodHandle:
1726 {
1727 int k1 = method_handle_ref_kind_at(index1);
1728 int k2 = cp2->method_handle_ref_kind_at(index2);
1729 if (k1 == k2) {
1730 int i1 = method_handle_index_at(index1);
1731 int i2 = cp2->method_handle_index_at(index2);
1732 if (compare_entry_to(i1, cp2, i2)) {
1733 return true;
1734 }
1735 }
1736 } break;
1737
1738 case JVM_CONSTANT_Dynamic:
1739 {
1740 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1741 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1742 int i1 = bootstrap_methods_attribute_index(index1);
1743 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1744 bool match_entry = compare_entry_to(k1, cp2, k2);
1745 bool match_operand = compare_operand_to(i1, cp2, i2);
1746 return (match_entry && match_operand);
1747 } break;
1748
1749 case JVM_CONSTANT_InvokeDynamic:
1750 {
1751 int k1 = bootstrap_name_and_type_ref_index_at(index1);
1752 int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1753 int i1 = bootstrap_methods_attribute_index(index1);
1754 int i2 = cp2->bootstrap_methods_attribute_index(index2);
1755 bool match_entry = compare_entry_to(k1, cp2, k2);
1756 bool match_operand = compare_operand_to(i1, cp2, i2);
1757 return (match_entry && match_operand);
1758 } break;
1759
1760 case JVM_CONSTANT_String:
1761 {
1762 Symbol* s1 = unresolved_string_at(index1);
1763 Symbol* s2 = cp2->unresolved_string_at(index2);
1764 if (s1 == s2) {
1765 return true;
1766 }
1767 } break;
1768
1769 case JVM_CONSTANT_Utf8:
1770 {
1771 Symbol* s1 = symbol_at(index1);
1772 Symbol* s2 = cp2->symbol_at(index2);
1773 if (s1 == s2) {
1774 return true;
1775 }
1776 } break;
1777
1778 // Invalid is used as the tag for the second constant pool entry
1779 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1780 // not be seen by itself.
1781 case JVM_CONSTANT_Invalid: // fall through
1782
1783 default:
1784 ShouldNotReachHere();
1785 break;
1786 }
1787
1788 return false;
1789 } // end compare_entry_to()
1790
1791
1792 // Resize the operands array with delta_len and delta_size.
1793 // Used in RedefineClasses for CP merge.
1794 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1795 int old_len = operand_array_length(operands());
1796 int new_len = old_len + delta_len;
1797 int min_len = (delta_len > 0) ? old_len : new_len;
1798
1799 int old_size = operands()->length();
1800 int new_size = old_size + delta_size;
1801 int min_size = (delta_size > 0) ? old_size : new_size;
1802
1803 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1804 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1805
1806 // Set index in the resized array for existing elements only
1807 for (int idx = 0; idx < min_len; idx++) {
1808 int offset = operand_offset_at(idx); // offset in original array
1809 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1810 }
1811 // Copy the bootstrap specifiers only
1812 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1813 new_ops->adr_at(2*new_len),
1814 (min_size - 2*min_len) * sizeof(u2));
1815 // Explicitly deallocate old operands array.
1816 // Note, it is not needed for 7u backport.
1817 if ( operands() != nullptr) { // the safety check
1818 MetadataFactory::free_array<u2>(loader_data, operands());
1819 }
1820 set_operands(new_ops);
1821 } // end resize_operands()
1822
1823
1824 // Extend the operands array with the length and size of the ext_cp operands.
1825 // Used in RedefineClasses for CP merge.
1826 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1827 int delta_len = operand_array_length(ext_cp->operands());
1828 if (delta_len == 0) {
1829 return; // nothing to do
1830 }
1831 int delta_size = ext_cp->operands()->length();
1832
1833 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1834
1835 if (operand_array_length(operands()) == 0) {
1836 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1837 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1838 // The first element index defines the offset of second part
1839 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1840 set_operands(new_ops);
1841 } else {
1842 resize_operands(delta_len, delta_size, CHECK);
1843 }
1844
1845 } // end extend_operands()
1846
1847
1848 // Shrink the operands array to a smaller array with new_len length.
1849 // Used in RedefineClasses for CP merge.
1850 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1851 int old_len = operand_array_length(operands());
1852 if (new_len == old_len) {
1853 return; // nothing to do
1854 }
1855 assert(new_len < old_len, "shrunken operands array must be smaller");
1856
1857 int free_base = operand_next_offset_at(new_len - 1);
1858 int delta_len = new_len - old_len;
1859 int delta_size = 2*delta_len + free_base - operands()->length();
1860
1861 resize_operands(delta_len, delta_size, CHECK);
1862
1863 } // end shrink_operands()
1864
1865
1866 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1867 const constantPoolHandle& to_cp,
1868 TRAPS) {
1869
1870 int from_oplen = operand_array_length(from_cp->operands());
1871 int old_oplen = operand_array_length(to_cp->operands());
1872 if (from_oplen != 0) {
1873 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1874 // append my operands to the target's operands array
1875 if (old_oplen == 0) {
1876 // Can't just reuse from_cp's operand list because of deallocation issues
1877 int len = from_cp->operands()->length();
1878 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1879 Copy::conjoint_memory_atomic(
1880 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1881 to_cp->set_operands(new_ops);
1882 } else {
1883 int old_len = to_cp->operands()->length();
1884 int from_len = from_cp->operands()->length();
1885 int old_off = old_oplen * sizeof(u2);
1886 int from_off = from_oplen * sizeof(u2);
1887 // Use the metaspace for the destination constant pool
1888 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1889 int fillp = 0, len = 0;
1890 // first part of dest
1891 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1892 new_operands->adr_at(fillp),
1893 (len = old_off) * sizeof(u2));
1894 fillp += len;
1895 // first part of src
1896 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1897 new_operands->adr_at(fillp),
1898 (len = from_off) * sizeof(u2));
1899 fillp += len;
1900 // second part of dest
1901 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1902 new_operands->adr_at(fillp),
1903 (len = old_len - old_off) * sizeof(u2));
1904 fillp += len;
1905 // second part of src
1906 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1907 new_operands->adr_at(fillp),
1908 (len = from_len - from_off) * sizeof(u2));
1909 fillp += len;
1910 assert(fillp == new_operands->length(), "");
1911
1912 // Adjust indexes in the first part of the copied operands array.
1913 for (int j = 0; j < from_oplen; j++) {
1914 int offset = operand_offset_at(new_operands, old_oplen + j);
1915 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1916 offset += old_len; // every new tuple is preceded by old_len extra u2's
1917 operand_offset_at_put(new_operands, old_oplen + j, offset);
1918 }
1919
1920 // replace target operands array with combined array
1921 to_cp->set_operands(new_operands);
1922 }
1923 }
1924 } // end copy_operands()
1925
1926
1927 // Copy this constant pool's entries at start_i to end_i (inclusive)
1928 // to the constant pool to_cp's entries starting at to_i. A total of
1929 // (end_i - start_i) + 1 entries are copied.
1930 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1931 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1932
1933
1934 int dest_cpi = to_i; // leave original alone for debug purposes
1935
1936 for (int src_cpi = start_i; src_cpi <= end_i; /* see loop bottom */ ) {
1937 copy_entry_to(from_cp, src_cpi, to_cp, dest_cpi);
1938
1939 switch (from_cp->tag_at(src_cpi).value()) {
1940 case JVM_CONSTANT_Double:
1941 case JVM_CONSTANT_Long:
1942 // double and long take two constant pool entries
1943 src_cpi += 2;
1944 dest_cpi += 2;
1945 break;
1946
1947 default:
1948 // all others take one constant pool entry
1949 src_cpi++;
1950 dest_cpi++;
1951 break;
1952 }
1953 }
1954 copy_operands(from_cp, to_cp, CHECK);
1955
1956 } // end copy_cp_to_impl()
1957
1958
1959 // Copy this constant pool's entry at from_i to the constant pool
1960 // to_cp's entry at to_i.
1961 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1962 const constantPoolHandle& to_cp, int to_i) {
1963
1964 int tag = from_cp->tag_at(from_i).value();
1965 switch (tag) {
1966 case JVM_CONSTANT_ClassIndex:
1967 {
1968 jint ki = from_cp->klass_index_at(from_i);
1969 to_cp->klass_index_at_put(to_i, ki);
1970 } break;
1971
1972 case JVM_CONSTANT_Double:
1973 {
1974 jdouble d = from_cp->double_at(from_i);
1975 to_cp->double_at_put(to_i, d);
1976 // double takes two constant pool entries so init second entry's tag
1977 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1978 } break;
1979
1980 case JVM_CONSTANT_Fieldref:
1981 {
1982 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1983 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1984 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1985 } break;
1986
1987 case JVM_CONSTANT_Float:
1988 {
1989 jfloat f = from_cp->float_at(from_i);
1990 to_cp->float_at_put(to_i, f);
1991 } break;
1992
1993 case JVM_CONSTANT_Integer:
1994 {
1995 jint i = from_cp->int_at(from_i);
1996 to_cp->int_at_put(to_i, i);
1997 } break;
1998
1999 case JVM_CONSTANT_InterfaceMethodref:
2000 {
2001 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
2002 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
2003 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
2004 } break;
2005
2006 case JVM_CONSTANT_Long:
2007 {
2008 jlong l = from_cp->long_at(from_i);
2009 to_cp->long_at_put(to_i, l);
2010 // long takes two constant pool entries so init second entry's tag
2011 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
2012 } break;
2013
2014 case JVM_CONSTANT_Methodref:
2015 {
2016 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
2017 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
2018 to_cp->method_at_put(to_i, class_index, name_and_type_index);
2019 } break;
2020
2021 case JVM_CONSTANT_NameAndType:
2022 {
2023 int name_ref_index = from_cp->name_ref_index_at(from_i);
2024 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
2025 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
2026 } break;
2027
2028 case JVM_CONSTANT_StringIndex:
2029 {
2030 jint si = from_cp->string_index_at(from_i);
2031 to_cp->string_index_at_put(to_i, si);
2032 } break;
2033
2034 case JVM_CONSTANT_Class:
2035 case JVM_CONSTANT_UnresolvedClass:
2036 case JVM_CONSTANT_UnresolvedClassInError:
2037 {
2038 // Revert to JVM_CONSTANT_ClassIndex
2039 int name_index = from_cp->klass_slot_at(from_i).name_index();
2040 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
2041 to_cp->klass_index_at_put(to_i, name_index);
2042 } break;
2043
2044 case JVM_CONSTANT_String:
2045 {
2046 Symbol* s = from_cp->unresolved_string_at(from_i);
2047 to_cp->unresolved_string_at_put(to_i, s);
2048 } break;
2049
2050 case JVM_CONSTANT_Utf8:
2051 {
2052 Symbol* s = from_cp->symbol_at(from_i);
2053 // Need to increase refcount, the old one will be thrown away and deferenced
2054 s->increment_refcount();
2055 to_cp->symbol_at_put(to_i, s);
2056 } break;
2057
2058 case JVM_CONSTANT_MethodType:
2059 case JVM_CONSTANT_MethodTypeInError:
2060 {
2061 jint k = from_cp->method_type_index_at(from_i);
2062 to_cp->method_type_index_at_put(to_i, k);
2063 } break;
2064
2065 case JVM_CONSTANT_MethodHandle:
2066 case JVM_CONSTANT_MethodHandleInError:
2067 {
2068 int k1 = from_cp->method_handle_ref_kind_at(from_i);
2069 int k2 = from_cp->method_handle_index_at(from_i);
2070 to_cp->method_handle_index_at_put(to_i, k1, k2);
2071 } break;
2072
2073 case JVM_CONSTANT_Dynamic:
2074 case JVM_CONSTANT_DynamicInError:
2075 {
2076 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
2077 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
2078 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
2079 to_cp->dynamic_constant_at_put(to_i, k1, k2);
2080 } break;
2081
2082 case JVM_CONSTANT_InvokeDynamic:
2083 {
2084 int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
2085 int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
2086 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
2087 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
2088 } break;
2089
2090 // Invalid is used as the tag for the second constant pool entry
2091 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
2092 // not be seen by itself.
2093 case JVM_CONSTANT_Invalid: // fall through
2094
2095 default:
2096 {
2097 ShouldNotReachHere();
2098 } break;
2099 }
2100 } // end copy_entry_to()
2101
2102 // Search constant pool search_cp for an entry that matches this
2103 // constant pool's entry at pattern_i. Returns the index of a
2104 // matching entry or zero (0) if there is no matching entry.
2105 int ConstantPool::find_matching_entry(int pattern_i,
2106 const constantPoolHandle& search_cp) {
2107
2108 // index zero (0) is not used
2109 for (int i = 1; i < search_cp->length(); i++) {
2110 bool found = compare_entry_to(pattern_i, search_cp, i);
2111 if (found) {
2112 return i;
2113 }
2114 }
2115
2116 return 0; // entry not found; return unused index zero (0)
2117 } // end find_matching_entry()
2118
2119
2120 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
2121 // cp2's bootstrap specifier at idx2.
2122 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2) {
2123 int k1 = operand_bootstrap_method_ref_index_at(idx1);
2124 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
2125 bool match = compare_entry_to(k1, cp2, k2);
2126
2127 if (!match) {
2128 return false;
2129 }
2130 int argc = operand_argument_count_at(idx1);
2131 if (argc == cp2->operand_argument_count_at(idx2)) {
2132 for (int j = 0; j < argc; j++) {
2133 k1 = operand_argument_index_at(idx1, j);
2134 k2 = cp2->operand_argument_index_at(idx2, j);
2135 match = compare_entry_to(k1, cp2, k2);
2136 if (!match) {
2137 return false;
2138 }
2139 }
2140 return true; // got through loop; all elements equal
2141 }
2142 return false;
2143 } // end compare_operand_to()
2144
2145 // Search constant pool search_cp for a bootstrap specifier that matches
2146 // this constant pool's bootstrap specifier data at pattern_i index.
2147 // Return the index of a matching bootstrap attribute record or (-1) if there is no match.
2148 int ConstantPool::find_matching_operand(int pattern_i,
2149 const constantPoolHandle& search_cp, int search_len) {
2150 for (int i = 0; i < search_len; i++) {
2151 bool found = compare_operand_to(pattern_i, search_cp, i);
2152 if (found) {
2153 return i;
2154 }
2155 }
2156 return -1; // bootstrap specifier data not found; return unused index (-1)
2157 } // end find_matching_operand()
2158
2159
2160 #ifndef PRODUCT
2161
2162 const char* ConstantPool::printable_name_at(int cp_index) {
2163
2164 constantTag tag = tag_at(cp_index);
2165
2166 if (tag.is_string()) {
2167 return string_at_noresolve(cp_index);
2168 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
2169 return klass_name_at(cp_index)->as_C_string();
2170 } else if (tag.is_symbol()) {
2171 return symbol_at(cp_index)->as_C_string();
2172 }
2173 return "";
2174 }
2175
2176 #endif // PRODUCT
2177
2178
2179 // JVMTI GetConstantPool support
2180
2181 // For debugging of constant pool
2182 const bool debug_cpool = false;
2183
2184 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
2185
2186 static void print_cpool_bytes(jint cnt, u1 *bytes) {
2187 const char* WARN_MSG = "Must not be such entry!";
2188 jint size = 0;
2189 u2 idx1, idx2;
2190
2191 for (jint idx = 1; idx < cnt; idx++) {
2192 jint ent_size = 0;
2193 u1 tag = *bytes++;
2194 size++; // count tag
2195
2196 printf("const #%03d, tag: %02d ", idx, tag);
2197 switch(tag) {
2198 case JVM_CONSTANT_Invalid: {
2199 printf("Invalid");
2200 break;
2201 }
2202 case JVM_CONSTANT_Unicode: {
2203 printf("Unicode %s", WARN_MSG);
2204 break;
2205 }
2206 case JVM_CONSTANT_Utf8: {
2207 u2 len = Bytes::get_Java_u2(bytes);
2208 char str[128];
2209 if (len > 127) {
2210 len = 127;
2211 }
2212 strncpy(str, (char *) (bytes+2), len);
2213 str[len] = '\0';
2214 printf("Utf8 \"%s\"", str);
2215 ent_size = 2 + len;
2216 break;
2217 }
2218 case JVM_CONSTANT_Integer: {
2219 u4 val = Bytes::get_Java_u4(bytes);
2220 printf("int %d", *(int *) &val);
2221 ent_size = 4;
2222 break;
2223 }
2224 case JVM_CONSTANT_Float: {
2225 u4 val = Bytes::get_Java_u4(bytes);
2226 printf("float %5.3ff", *(float *) &val);
2227 ent_size = 4;
2228 break;
2229 }
2230 case JVM_CONSTANT_Long: {
2231 u8 val = Bytes::get_Java_u8(bytes);
2232 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
2233 ent_size = 8;
2234 idx++; // Long takes two cpool slots
2235 break;
2236 }
2237 case JVM_CONSTANT_Double: {
2238 u8 val = Bytes::get_Java_u8(bytes);
2239 printf("double %5.3fd", *(jdouble *)&val);
2240 ent_size = 8;
2241 idx++; // Double takes two cpool slots
2242 break;
2243 }
2244 case JVM_CONSTANT_Class: {
2245 idx1 = Bytes::get_Java_u2(bytes);
2246 printf("class #%03d", idx1);
2247 ent_size = 2;
2248 break;
2249 }
2250 case JVM_CONSTANT_String: {
2251 idx1 = Bytes::get_Java_u2(bytes);
2252 printf("String #%03d", idx1);
2253 ent_size = 2;
2254 break;
2255 }
2256 case JVM_CONSTANT_Fieldref: {
2257 idx1 = Bytes::get_Java_u2(bytes);
2258 idx2 = Bytes::get_Java_u2(bytes+2);
2259 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
2260 ent_size = 4;
2261 break;
2262 }
2263 case JVM_CONSTANT_Methodref: {
2264 idx1 = Bytes::get_Java_u2(bytes);
2265 idx2 = Bytes::get_Java_u2(bytes+2);
2266 printf("Method #%03d, #%03d", idx1, idx2);
2267 ent_size = 4;
2268 break;
2269 }
2270 case JVM_CONSTANT_InterfaceMethodref: {
2271 idx1 = Bytes::get_Java_u2(bytes);
2272 idx2 = Bytes::get_Java_u2(bytes+2);
2273 printf("InterfMethod #%03d, #%03d", idx1, idx2);
2274 ent_size = 4;
2275 break;
2276 }
2277 case JVM_CONSTANT_NameAndType: {
2278 idx1 = Bytes::get_Java_u2(bytes);
2279 idx2 = Bytes::get_Java_u2(bytes+2);
2280 printf("NameAndType #%03d, #%03d", idx1, idx2);
2281 ent_size = 4;
2282 break;
2283 }
2284 case JVM_CONSTANT_ClassIndex: {
2285 printf("ClassIndex %s", WARN_MSG);
2286 break;
2287 }
2288 case JVM_CONSTANT_UnresolvedClass: {
2289 printf("UnresolvedClass: %s", WARN_MSG);
2290 break;
2291 }
2292 case JVM_CONSTANT_UnresolvedClassInError: {
2293 printf("UnresolvedClassInErr: %s", WARN_MSG);
2294 break;
2295 }
2296 case JVM_CONSTANT_StringIndex: {
2297 printf("StringIndex: %s", WARN_MSG);
2298 break;
2299 }
2300 }
2301 printf(";\n");
2302 bytes += ent_size;
2303 size += ent_size;
2304 }
2305 printf("Cpool size: %d\n", size);
2306 fflush(0);
2307 return;
2308 } /* end print_cpool_bytes */
2309
2310
2311 // Returns size of constant pool entry.
2312 jint ConstantPool::cpool_entry_size(jint idx) {
2313 switch(tag_at(idx).value()) {
2314 case JVM_CONSTANT_Invalid:
2315 case JVM_CONSTANT_Unicode:
2316 return 1;
2317
2318 case JVM_CONSTANT_Utf8:
2319 return 3 + symbol_at(idx)->utf8_length();
2320
2321 case JVM_CONSTANT_Class:
2322 case JVM_CONSTANT_String:
2323 case JVM_CONSTANT_ClassIndex:
2324 case JVM_CONSTANT_UnresolvedClass:
2325 case JVM_CONSTANT_UnresolvedClassInError:
2326 case JVM_CONSTANT_StringIndex:
2327 case JVM_CONSTANT_MethodType:
2328 case JVM_CONSTANT_MethodTypeInError:
2329 return 3;
2330
2331 case JVM_CONSTANT_MethodHandle:
2332 case JVM_CONSTANT_MethodHandleInError:
2333 return 4; //tag, ref_kind, ref_index
2334
2335 case JVM_CONSTANT_Integer:
2336 case JVM_CONSTANT_Float:
2337 case JVM_CONSTANT_Fieldref:
2338 case JVM_CONSTANT_Methodref:
2339 case JVM_CONSTANT_InterfaceMethodref:
2340 case JVM_CONSTANT_NameAndType:
2341 return 5;
2342
2343 case JVM_CONSTANT_Dynamic:
2344 case JVM_CONSTANT_DynamicInError:
2345 case JVM_CONSTANT_InvokeDynamic:
2346 // u1 tag, u2 bsm, u2 nt
2347 return 5;
2348
2349 case JVM_CONSTANT_Long:
2350 case JVM_CONSTANT_Double:
2351 return 9;
2352 }
2353 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2354 return 1;
2355 } /* end cpool_entry_size */
2356
2357
2358 // SymbolHash is used to find a constant pool index from a string.
2359 // This function fills in SymbolHashs, one for utf8s and one for
2360 // class names, returns size of the cpool raw bytes.
2361 jint ConstantPool::hash_entries_to(SymbolHash *symmap,
2362 SymbolHash *classmap) {
2363 jint size = 0;
2364
2365 for (u2 idx = 1; idx < length(); idx++) {
2366 u2 tag = tag_at(idx).value();
2367 size += cpool_entry_size(idx);
2368
2369 switch(tag) {
2370 case JVM_CONSTANT_Utf8: {
2371 Symbol* sym = symbol_at(idx);
2372 symmap->add_if_absent(sym, idx);
2373 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
2374 break;
2375 }
2376 case JVM_CONSTANT_Class:
2377 case JVM_CONSTANT_UnresolvedClass:
2378 case JVM_CONSTANT_UnresolvedClassInError: {
2379 Symbol* sym = klass_name_at(idx);
2380 classmap->add_if_absent(sym, idx);
2381 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
2382 break;
2383 }
2384 case JVM_CONSTANT_Long:
2385 case JVM_CONSTANT_Double: {
2386 idx++; // Both Long and Double take two cpool slots
2387 break;
2388 }
2389 }
2390 }
2391 return size;
2392 } /* end hash_utf8_entries_to */
2393
2394
2395 // Copy cpool bytes.
2396 // Returns:
2397 // 0, in case of OutOfMemoryError
2398 // -1, in case of internal error
2399 // > 0, count of the raw cpool bytes that have been copied
2400 int ConstantPool::copy_cpool_bytes(int cpool_size,
2401 SymbolHash* tbl,
2402 unsigned char *bytes) {
2403 u2 idx1, idx2;
2404 jint size = 0;
2405 jint cnt = length();
2406 unsigned char *start_bytes = bytes;
2407
2408 for (jint idx = 1; idx < cnt; idx++) {
2409 u1 tag = tag_at(idx).value();
2410 jint ent_size = cpool_entry_size(idx);
2411
2412 assert(size + ent_size <= cpool_size, "Size mismatch");
2413
2414 *bytes = tag;
2415 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
2416 switch(tag) {
2417 case JVM_CONSTANT_Invalid: {
2418 DBG(printf("JVM_CONSTANT_Invalid"));
2419 break;
2420 }
2421 case JVM_CONSTANT_Unicode: {
2422 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2423 DBG(printf("JVM_CONSTANT_Unicode"));
2424 break;
2425 }
2426 case JVM_CONSTANT_Utf8: {
2427 Symbol* sym = symbol_at(idx);
2428 char* str = sym->as_utf8();
2429 // Warning! It's crashing on x86 with len = sym->utf8_length()
2430 int len = (int) strlen(str);
2431 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2432 for (int i = 0; i < len; i++) {
2433 bytes[3+i] = (u1) str[i];
2434 }
2435 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
2436 break;
2437 }
2438 case JVM_CONSTANT_Integer: {
2439 jint val = int_at(idx);
2440 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2441 break;
2442 }
2443 case JVM_CONSTANT_Float: {
2444 jfloat val = float_at(idx);
2445 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2446 break;
2447 }
2448 case JVM_CONSTANT_Long: {
2449 jlong val = long_at(idx);
2450 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2451 idx++; // Long takes two cpool slots
2452 break;
2453 }
2454 case JVM_CONSTANT_Double: {
2455 jdouble val = double_at(idx);
2456 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2457 idx++; // Double takes two cpool slots
2458 break;
2459 }
2460 case JVM_CONSTANT_Class:
2461 case JVM_CONSTANT_UnresolvedClass:
2462 case JVM_CONSTANT_UnresolvedClassInError: {
2463 *bytes = JVM_CONSTANT_Class;
2464 Symbol* sym = klass_name_at(idx);
2465 idx1 = tbl->symbol_to_value(sym);
2466 assert(idx1 != 0, "Have not found a hashtable entry");
2467 Bytes::put_Java_u2((address) (bytes+1), idx1);
2468 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
2469 break;
2470 }
2471 case JVM_CONSTANT_String: {
2472 *bytes = JVM_CONSTANT_String;
2473 Symbol* sym = unresolved_string_at(idx);
2474 idx1 = tbl->symbol_to_value(sym);
2475 assert(idx1 != 0, "Have not found a hashtable entry");
2476 Bytes::put_Java_u2((address) (bytes+1), idx1);
2477 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
2478 break;
2479 }
2480 case JVM_CONSTANT_Fieldref:
2481 case JVM_CONSTANT_Methodref:
2482 case JVM_CONSTANT_InterfaceMethodref: {
2483 idx1 = uncached_klass_ref_index_at(idx);
2484 idx2 = uncached_name_and_type_ref_index_at(idx);
2485 Bytes::put_Java_u2((address) (bytes+1), idx1);
2486 Bytes::put_Java_u2((address) (bytes+3), idx2);
2487 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
2488 break;
2489 }
2490 case JVM_CONSTANT_NameAndType: {
2491 idx1 = name_ref_index_at(idx);
2492 idx2 = signature_ref_index_at(idx);
2493 Bytes::put_Java_u2((address) (bytes+1), idx1);
2494 Bytes::put_Java_u2((address) (bytes+3), idx2);
2495 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
2496 break;
2497 }
2498 case JVM_CONSTANT_ClassIndex: {
2499 *bytes = JVM_CONSTANT_Class;
2500 idx1 = checked_cast<u2>(klass_index_at(idx));
2501 Bytes::put_Java_u2((address) (bytes+1), idx1);
2502 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
2503 break;
2504 }
2505 case JVM_CONSTANT_StringIndex: {
2506 *bytes = JVM_CONSTANT_String;
2507 idx1 = checked_cast<u2>(string_index_at(idx));
2508 Bytes::put_Java_u2((address) (bytes+1), idx1);
2509 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
2510 break;
2511 }
2512 case JVM_CONSTANT_MethodHandle:
2513 case JVM_CONSTANT_MethodHandleInError: {
2514 *bytes = JVM_CONSTANT_MethodHandle;
2515 int kind = method_handle_ref_kind_at(idx);
2516 idx1 = checked_cast<u2>(method_handle_index_at(idx));
2517 *(bytes+1) = (unsigned char) kind;
2518 Bytes::put_Java_u2((address) (bytes+2), idx1);
2519 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
2520 break;
2521 }
2522 case JVM_CONSTANT_MethodType:
2523 case JVM_CONSTANT_MethodTypeInError: {
2524 *bytes = JVM_CONSTANT_MethodType;
2525 idx1 = checked_cast<u2>(method_type_index_at(idx));
2526 Bytes::put_Java_u2((address) (bytes+1), idx1);
2527 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
2528 break;
2529 }
2530 case JVM_CONSTANT_Dynamic:
2531 case JVM_CONSTANT_DynamicInError: {
2532 *bytes = tag;
2533 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2534 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2535 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2536 Bytes::put_Java_u2((address) (bytes+1), idx1);
2537 Bytes::put_Java_u2((address) (bytes+3), idx2);
2538 DBG(printf("JVM_CONSTANT_Dynamic: %hd %hd", idx1, idx2));
2539 break;
2540 }
2541 case JVM_CONSTANT_InvokeDynamic: {
2542 *bytes = tag;
2543 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2544 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2545 assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2546 Bytes::put_Java_u2((address) (bytes+1), idx1);
2547 Bytes::put_Java_u2((address) (bytes+3), idx2);
2548 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
2549 break;
2550 }
2551 }
2552 DBG(printf("\n"));
2553 bytes += ent_size;
2554 size += ent_size;
2555 }
2556 assert(size == cpool_size, "Size mismatch");
2557
2558 // Keep temporarily for debugging until it's stable.
2559 DBG(print_cpool_bytes(cnt, start_bytes));
2560 return (int)(bytes - start_bytes);
2561 } /* end copy_cpool_bytes */
2562
2563 #undef DBG
2564
2565 bool ConstantPool::is_maybe_on_stack() const {
2566 // This method uses the similar logic as nmethod::is_maybe_on_stack()
2567 if (!Continuations::enabled()) {
2568 return false;
2569 }
2570
2571 // If the condition below is true, it means that the nmethod was found to
2572 // be alive the previous completed marking cycle.
2573 return cache()->gc_epoch() >= CodeCache::previous_completed_gc_marking_cycle();
2574 }
2575
2576 // For redefinition, if any methods found in loom stack chunks, the gc_epoch is
2577 // recorded in their constant pool cache. The on_stack-ness of the constant pool controls whether
2578 // memory for the method is reclaimed.
2579 bool ConstantPool::on_stack() const {
2580 if ((_flags &_on_stack) != 0) {
2581 return true;
2582 }
2583
2584 if (_cache == nullptr) {
2585 return false;
2586 }
2587
2588 return is_maybe_on_stack();
2589 }
2590
2591 void ConstantPool::set_on_stack(const bool value) {
2592 if (value) {
2593 // Only record if it's not already set.
2594 if (!on_stack()) {
2595 assert(!is_shared(), "should always be set for shared constant pools");
2596 _flags |= _on_stack;
2597 MetadataOnStackMark::record(this);
2598 }
2599 } else {
2600 // Clearing is done single-threadedly.
2601 if (!is_shared()) {
2602 _flags &= (u2)(~_on_stack);
2603 }
2604 }
2605 }
2606
2607 // Printing
2608
2609 void ConstantPool::print_on(outputStream* st) const {
2610 assert(is_constantPool(), "must be constantPool");
2611 st->print_cr("%s", internal_name());
2612 if (flags() != 0) {
2613 st->print(" - flags: 0x%x", flags());
2614 if (has_preresolution()) st->print(" has_preresolution");
2615 if (on_stack()) st->print(" on_stack");
2616 st->cr();
2617 }
2618 if (pool_holder() != nullptr) {
2619 st->print_cr(" - holder: " PTR_FORMAT, p2i(pool_holder()));
2620 }
2621 st->print_cr(" - cache: " PTR_FORMAT, p2i(cache()));
2622 st->print_cr(" - resolved_references: " PTR_FORMAT, p2i(resolved_references_or_null()));
2623 st->print_cr(" - reference_map: " PTR_FORMAT, p2i(reference_map()));
2624 st->print_cr(" - resolved_klasses: " PTR_FORMAT, p2i(resolved_klasses()));
2625 st->print_cr(" - cp length: %d", length());
2626
2627 for (int index = 1; index < length(); index++) { // Index 0 is unused
2628 ((ConstantPool*)this)->print_entry_on(index, st);
2629 switch (tag_at(index).value()) {
2630 case JVM_CONSTANT_Long :
2631 case JVM_CONSTANT_Double :
2632 index++; // Skip entry following eigth-byte constant
2633 }
2634
2635 }
2636 st->cr();
2637 }
2638
2639 // Print one constant pool entry
2640 void ConstantPool::print_entry_on(const int cp_index, outputStream* st) {
2641 EXCEPTION_MARK;
2642 st->print(" - %3d : ", cp_index);
2643 tag_at(cp_index).print_on(st);
2644 st->print(" : ");
2645 switch (tag_at(cp_index).value()) {
2646 case JVM_CONSTANT_Class :
2647 { Klass* k = klass_at(cp_index, CATCH);
2648 guarantee(k != nullptr, "need klass");
2649 k->print_value_on(st);
2650 st->print(" {" PTR_FORMAT "}", p2i(k));
2651 }
2652 break;
2653 case JVM_CONSTANT_Fieldref :
2654 case JVM_CONSTANT_Methodref :
2655 case JVM_CONSTANT_InterfaceMethodref :
2656 st->print("klass_index=%d", uncached_klass_ref_index_at(cp_index));
2657 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(cp_index));
2658 break;
2659 case JVM_CONSTANT_String :
2660 unresolved_string_at(cp_index)->print_value_on(st);
2661 break;
2662 case JVM_CONSTANT_Integer :
2663 st->print("%d", int_at(cp_index));
2664 break;
2665 case JVM_CONSTANT_Float :
2666 st->print("%f", float_at(cp_index));
2667 break;
2668 case JVM_CONSTANT_Long :
2669 st->print_jlong(long_at(cp_index));
2670 break;
2671 case JVM_CONSTANT_Double :
2672 st->print("%lf", double_at(cp_index));
2673 break;
2674 case JVM_CONSTANT_NameAndType :
2675 st->print("name_index=%d", name_ref_index_at(cp_index));
2676 st->print(" signature_index=%d", signature_ref_index_at(cp_index));
2677 break;
2678 case JVM_CONSTANT_Utf8 :
2679 symbol_at(cp_index)->print_value_on(st);
2680 break;
2681 case JVM_CONSTANT_ClassIndex: {
2682 int name_index = *int_at_addr(cp_index);
2683 st->print("klass_index=%d ", name_index);
2684 symbol_at(name_index)->print_value_on(st);
2685 }
2686 break;
2687 case JVM_CONSTANT_UnresolvedClass : // fall-through
2688 case JVM_CONSTANT_UnresolvedClassInError: {
2689 CPKlassSlot kslot = klass_slot_at(cp_index);
2690 int resolved_klass_index = kslot.resolved_klass_index();
2691 int name_index = kslot.name_index();
2692 assert(tag_at(name_index).is_symbol(), "sanity");
2693 symbol_at(name_index)->print_value_on(st);
2694 }
2695 break;
2696 case JVM_CONSTANT_MethodHandle :
2697 case JVM_CONSTANT_MethodHandleInError :
2698 st->print("ref_kind=%d", method_handle_ref_kind_at(cp_index));
2699 st->print(" ref_index=%d", method_handle_index_at(cp_index));
2700 break;
2701 case JVM_CONSTANT_MethodType :
2702 case JVM_CONSTANT_MethodTypeInError :
2703 st->print("signature_index=%d", method_type_index_at(cp_index));
2704 break;
2705 case JVM_CONSTANT_Dynamic :
2706 case JVM_CONSTANT_DynamicInError :
2707 {
2708 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2709 st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2710 int argc = bootstrap_argument_count_at(cp_index);
2711 if (argc > 0) {
2712 for (int arg_i = 0; arg_i < argc; arg_i++) {
2713 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2714 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2715 }
2716 st->print("}");
2717 }
2718 }
2719 break;
2720 case JVM_CONSTANT_InvokeDynamic :
2721 {
2722 st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(cp_index));
2723 st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(cp_index));
2724 int argc = bootstrap_argument_count_at(cp_index);
2725 if (argc > 0) {
2726 for (int arg_i = 0; arg_i < argc; arg_i++) {
2727 int arg = bootstrap_argument_index_at(cp_index, arg_i);
2728 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2729 }
2730 st->print("}");
2731 }
2732 }
2733 break;
2734 default:
2735 ShouldNotReachHere();
2736 break;
2737 }
2738 st->cr();
2739 }
2740
2741 void ConstantPool::print_value_on(outputStream* st) const {
2742 assert(is_constantPool(), "must be constantPool");
2743 st->print("constant pool [%d]", length());
2744 if (has_preresolution()) st->print("/preresolution");
2745 if (operands() != nullptr) st->print("/operands[%d]", operands()->length());
2746 print_address_on(st);
2747 if (pool_holder() != nullptr) {
2748 st->print(" for ");
2749 pool_holder()->print_value_on(st);
2750 bool extra = (pool_holder()->constants() != this);
2751 if (extra) st->print(" (extra)");
2752 }
2753 if (cache() != nullptr) {
2754 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2755 }
2756 }
2757
2758 // Verification
2759
2760 void ConstantPool::verify_on(outputStream* st) {
2761 guarantee(is_constantPool(), "object must be constant pool");
2762 for (int i = 0; i< length(); i++) {
2763 constantTag tag = tag_at(i);
2764 if (tag.is_klass() || tag.is_unresolved_klass()) {
2765 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2766 } else if (tag.is_symbol()) {
2767 Symbol* entry = symbol_at(i);
2768 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2769 } else if (tag.is_string()) {
2770 Symbol* entry = unresolved_string_at(i);
2771 guarantee(entry->refcount() != 0, "should have nonzero reference count");
2772 }
2773 }
2774 if (pool_holder() != nullptr) {
2775 // Note: pool_holder() can be null in temporary constant pools
2776 // used during constant pool merging
2777 guarantee(pool_holder()->is_klass(), "should be klass");
2778 }
2779 }