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