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