Wed, 04 Jul 2018 03:02:43 -0400
8081323: ConstantPool::_resolved_references is missing in heap dump
Summary: Add resolved_references and init_lock as hidden static field in class so root is found.
Reviewed-by: dholmes, coleenp
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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25 #include "precompiled.hpp"
26 #include "classfile/classLoaderData.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/metadataOnStackMark.hpp"
29 #include "classfile/symbolTable.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "interpreter/linkResolver.hpp"
33 #include "memory/heapInspection.hpp"
34 #include "memory/metadataFactory.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "oops/constantPool.hpp"
37 #include "oops/instanceKlass.hpp"
38 #include "oops/objArrayKlass.hpp"
39 #include "runtime/fieldType.hpp"
40 #include "runtime/init.hpp"
41 #include "runtime/javaCalls.hpp"
42 #include "runtime/signature.hpp"
43 #include "runtime/vframe.hpp"
45 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
47 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
48 // Tags are RW but comment below applies to tags also.
49 Array<u1>* tags = MetadataFactory::new_writeable_array<u1>(loader_data, length, 0, CHECK_NULL);
51 int size = ConstantPool::size(length);
53 // CDS considerations:
54 // Allocate read-write but may be able to move to read-only at dumping time
55 // if all the klasses are resolved. The only other field that is writable is
56 // the resolved_references array, which is recreated at startup time.
57 // But that could be moved to InstanceKlass (although a pain to access from
58 // assembly code). Maybe it could be moved to the cpCache which is RW.
59 return new (loader_data, size, false, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
60 }
62 ConstantPool::ConstantPool(Array<u1>* tags) {
63 set_length(tags->length());
64 set_tags(NULL);
65 set_cache(NULL);
66 set_reference_map(NULL);
67 set_resolved_references(NULL);
68 set_operands(NULL);
69 set_pool_holder(NULL);
70 set_flags(0);
72 // only set to non-zero if constant pool is merged by RedefineClasses
73 set_version(0);
74 set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
76 // initialize tag array
77 int length = tags->length();
78 for (int index = 0; index < length; index++) {
79 tags->at_put(index, JVM_CONSTANT_Invalid);
80 }
81 set_tags(tags);
82 }
84 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
85 MetadataFactory::free_metadata(loader_data, cache());
86 set_cache(NULL);
87 MetadataFactory::free_array<u2>(loader_data, reference_map());
88 set_reference_map(NULL);
90 MetadataFactory::free_array<jushort>(loader_data, operands());
91 set_operands(NULL);
93 release_C_heap_structures();
95 // free tag array
96 MetadataFactory::free_array<u1>(loader_data, tags());
97 set_tags(NULL);
98 }
100 void ConstantPool::release_C_heap_structures() {
101 // walk constant pool and decrement symbol reference counts
102 unreference_symbols();
104 delete _lock;
105 set_lock(NULL);
106 }
108 objArrayOop ConstantPool::resolved_references() const {
109 return (objArrayOop)JNIHandles::resolve(_resolved_references);
110 }
112 // Called from outside constant pool resolution where a resolved_reference array
113 // may not be present.
114 objArrayOop ConstantPool::resolved_references_or_null() const {
115 if (_cache == NULL) {
116 return NULL;
117 } else {
118 return (objArrayOop)JNIHandles::resolve(_resolved_references);
119 }
120 }
122 // Create resolved_references array and mapping array for original cp indexes
123 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
124 // to map it back for resolving and some unlikely miscellaneous uses.
125 // The objects created by invokedynamic are appended to this list.
126 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
127 intStack reference_map,
128 int constant_pool_map_length,
129 TRAPS) {
130 // Initialized the resolved object cache.
131 int map_length = reference_map.length();
132 if (map_length > 0) {
133 // Only need mapping back to constant pool entries. The map isn't used for
134 // invokedynamic resolved_reference entries. For invokedynamic entries,
135 // the constant pool cache index has the mapping back to both the constant
136 // pool and to the resolved reference index.
137 if (constant_pool_map_length > 0) {
138 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
140 for (int i = 0; i < constant_pool_map_length; i++) {
141 int x = reference_map.at(i);
142 assert(x == (int)(jushort) x, "klass index is too big");
143 om->at_put(i, (jushort)x);
144 }
145 set_reference_map(om);
146 }
148 // Create Java array for holding resolved strings, methodHandles,
149 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
150 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
151 Handle refs_handle (THREAD, (oop)stom); // must handleize.
152 set_resolved_references(loader_data->add_handle(refs_handle));
153 }
154 }
156 // CDS support. Create a new resolved_references array.
157 void ConstantPool::restore_unshareable_info(TRAPS) {
159 // Only create the new resolved references array and lock if it hasn't been
160 // attempted before
161 if (resolved_references() != NULL) return;
163 // restore the C++ vtable from the shared archive
164 restore_vtable();
166 if (SystemDictionary::Object_klass_loaded()) {
167 // Recreate the object array and add to ClassLoaderData.
168 int map_length = resolved_reference_length();
169 if (map_length > 0) {
170 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
171 Handle refs_handle (THREAD, (oop)stom); // must handleize.
173 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
174 set_resolved_references(loader_data->add_handle(refs_handle));
175 }
177 // Also need to recreate the mutex. Make sure this matches the constructor
178 set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
179 }
180 }
182 void ConstantPool::remove_unshareable_info() {
183 // Resolved references are not in the shared archive.
184 // Save the length for restoration. It is not necessarily the same length
185 // as reference_map.length() if invokedynamic is saved.
186 set_resolved_reference_length(
187 resolved_references() != NULL ? resolved_references()->length() : 0);
188 set_resolved_references(NULL);
189 set_lock(NULL);
190 }
192 int ConstantPool::cp_to_object_index(int cp_index) {
193 // this is harder don't do this so much.
194 int i = reference_map()->find(cp_index);
195 // We might not find the index for jsr292 call.
196 return (i < 0) ? _no_index_sentinel : i;
197 }
199 Klass* ConstantPool::klass_at_impl(constantPoolHandle this_oop, int which, TRAPS) {
200 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
201 // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
202 // tag is not updated atomicly.
204 CPSlot entry = this_oop->slot_at(which);
205 if (entry.is_resolved()) {
206 assert(entry.get_klass()->is_klass(), "must be");
207 // Already resolved - return entry.
208 return entry.get_klass();
209 }
211 // Acquire lock on constant oop while doing update. After we get the lock, we check if another object
212 // already has updated the object
213 assert(THREAD->is_Java_thread(), "must be a Java thread");
214 bool do_resolve = false;
215 bool in_error = false;
217 // Create a handle for the mirror. This will preserve the resolved class
218 // until the loader_data is registered.
219 Handle mirror_handle;
221 Symbol* name = NULL;
222 Handle loader;
223 { MonitorLockerEx ml(this_oop->lock());
225 if (this_oop->tag_at(which).is_unresolved_klass()) {
226 if (this_oop->tag_at(which).is_unresolved_klass_in_error()) {
227 in_error = true;
228 } else {
229 do_resolve = true;
230 name = this_oop->unresolved_klass_at(which);
231 loader = Handle(THREAD, this_oop->pool_holder()->class_loader());
232 }
233 }
234 } // unlocking constantPool
237 // The original attempt to resolve this constant pool entry failed so find the
238 // original error and throw it again (JVMS 5.4.3).
239 if (in_error) {
240 Symbol* error = SystemDictionary::find_resolution_error(this_oop, which);
241 guarantee(error != (Symbol*)NULL, "tag mismatch with resolution error table");
242 ResourceMark rm;
243 // exception text will be the class name
244 const char* className = this_oop->unresolved_klass_at(which)->as_C_string();
245 THROW_MSG_0(error, className);
246 }
248 if (do_resolve) {
249 // this_oop must be unlocked during resolve_or_fail
250 oop protection_domain = this_oop->pool_holder()->protection_domain();
251 Handle h_prot (THREAD, protection_domain);
252 Klass* k_oop = SystemDictionary::resolve_or_fail(name, loader, h_prot, true, THREAD);
253 KlassHandle k;
254 if (!HAS_PENDING_EXCEPTION) {
255 k = KlassHandle(THREAD, k_oop);
256 // preserve the resolved klass.
257 mirror_handle = Handle(THREAD, k_oop->java_mirror());
258 // Do access check for klasses
259 verify_constant_pool_resolve(this_oop, k, THREAD);
260 }
262 // Failed to resolve class. We must record the errors so that subsequent attempts
263 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
264 if (HAS_PENDING_EXCEPTION) {
265 ResourceMark rm;
266 Symbol* error = PENDING_EXCEPTION->klass()->name();
268 bool throw_orig_error = false;
269 {
270 MonitorLockerEx ml(this_oop->lock());
272 // some other thread has beaten us and has resolved the class.
273 if (this_oop->tag_at(which).is_klass()) {
274 CLEAR_PENDING_EXCEPTION;
275 entry = this_oop->resolved_klass_at(which);
276 return entry.get_klass();
277 }
279 if (!PENDING_EXCEPTION->
280 is_a(SystemDictionary::LinkageError_klass())) {
281 // Just throw the exception and don't prevent these classes from
282 // being loaded due to virtual machine errors like StackOverflow
283 // and OutOfMemoryError, etc, or if the thread was hit by stop()
284 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
285 }
286 else if (!this_oop->tag_at(which).is_unresolved_klass_in_error()) {
287 SystemDictionary::add_resolution_error(this_oop, which, error);
288 this_oop->tag_at_put(which, JVM_CONSTANT_UnresolvedClassInError);
289 } else {
290 // some other thread has put the class in error state.
291 error = SystemDictionary::find_resolution_error(this_oop, which);
292 assert(error != NULL, "checking");
293 throw_orig_error = true;
294 }
295 } // unlocked
297 if (throw_orig_error) {
298 CLEAR_PENDING_EXCEPTION;
299 ResourceMark rm;
300 const char* className = this_oop->unresolved_klass_at(which)->as_C_string();
301 THROW_MSG_0(error, className);
302 }
304 return 0;
305 }
307 if (TraceClassResolution && !k()->oop_is_array()) {
308 // skip resolving the constant pool so that this code get's
309 // called the next time some bytecodes refer to this class.
310 ResourceMark rm;
311 int line_number = -1;
312 const char * source_file = NULL;
313 if (JavaThread::current()->has_last_Java_frame()) {
314 // try to identify the method which called this function.
315 vframeStream vfst(JavaThread::current());
316 if (!vfst.at_end()) {
317 line_number = vfst.method()->line_number_from_bci(vfst.bci());
318 Symbol* s = vfst.method()->method_holder()->source_file_name();
319 if (s != NULL) {
320 source_file = s->as_C_string();
321 }
322 }
323 }
324 if (k() != this_oop->pool_holder()) {
325 // only print something if the classes are different
326 if (source_file != NULL) {
327 tty->print("RESOLVE %s %s %s:%d\n",
328 this_oop->pool_holder()->external_name(),
329 InstanceKlass::cast(k())->external_name(), source_file, line_number);
330 } else {
331 tty->print("RESOLVE %s %s\n",
332 this_oop->pool_holder()->external_name(),
333 InstanceKlass::cast(k())->external_name());
334 }
335 }
336 return k();
337 } else {
338 MonitorLockerEx ml(this_oop->lock());
339 // Only updated constant pool - if it is resolved.
340 do_resolve = this_oop->tag_at(which).is_unresolved_klass();
341 if (do_resolve) {
342 ClassLoaderData* this_key = this_oop->pool_holder()->class_loader_data();
343 this_key->record_dependency(k(), CHECK_NULL); // Can throw OOM
344 this_oop->klass_at_put(which, k());
345 }
346 }
347 }
349 entry = this_oop->resolved_klass_at(which);
350 assert(entry.is_resolved() && entry.get_klass()->is_klass(), "must be resolved at this point");
351 return entry.get_klass();
352 }
355 // Does not update ConstantPool* - to avoid any exception throwing. Used
356 // by compiler and exception handling. Also used to avoid classloads for
357 // instanceof operations. Returns NULL if the class has not been loaded or
358 // if the verification of constant pool failed
359 Klass* ConstantPool::klass_at_if_loaded(constantPoolHandle this_oop, int which) {
360 CPSlot entry = this_oop->slot_at(which);
361 if (entry.is_resolved()) {
362 assert(entry.get_klass()->is_klass(), "must be");
363 return entry.get_klass();
364 } else {
365 assert(entry.is_unresolved(), "must be either symbol or klass");
366 Thread *thread = Thread::current();
367 Symbol* name = entry.get_symbol();
368 oop loader = this_oop->pool_holder()->class_loader();
369 oop protection_domain = this_oop->pool_holder()->protection_domain();
370 Handle h_prot (thread, protection_domain);
371 Handle h_loader (thread, loader);
372 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
374 if (k != NULL) {
375 // Make sure that resolving is legal
376 EXCEPTION_MARK;
377 KlassHandle klass(THREAD, k);
378 // return NULL if verification fails
379 verify_constant_pool_resolve(this_oop, klass, THREAD);
380 if (HAS_PENDING_EXCEPTION) {
381 CLEAR_PENDING_EXCEPTION;
382 return NULL;
383 }
384 return klass();
385 } else {
386 return k;
387 }
388 }
389 }
392 Klass* ConstantPool::klass_ref_at_if_loaded(constantPoolHandle this_oop, int which) {
393 return klass_at_if_loaded(this_oop, this_oop->klass_ref_index_at(which));
394 }
397 Method* ConstantPool::method_at_if_loaded(constantPoolHandle cpool,
398 int which) {
399 if (cpool->cache() == NULL) return NULL; // nothing to load yet
400 int cache_index = decode_cpcache_index(which, true);
401 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
402 // FIXME: should be an assert
403 if (PrintMiscellaneous && (Verbose||WizardMode)) {
404 tty->print_cr("bad operand %d in:", which); cpool->print();
405 }
406 return NULL;
407 }
408 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
409 return e->method_if_resolved(cpool);
410 }
413 bool ConstantPool::has_appendix_at_if_loaded(constantPoolHandle cpool, int which) {
414 if (cpool->cache() == NULL) return false; // nothing to load yet
415 int cache_index = decode_cpcache_index(which, true);
416 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
417 return e->has_appendix();
418 }
420 oop ConstantPool::appendix_at_if_loaded(constantPoolHandle cpool, int which) {
421 if (cpool->cache() == NULL) return NULL; // nothing to load yet
422 int cache_index = decode_cpcache_index(which, true);
423 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
424 return e->appendix_if_resolved(cpool);
425 }
428 bool ConstantPool::has_method_type_at_if_loaded(constantPoolHandle cpool, int which) {
429 if (cpool->cache() == NULL) return false; // nothing to load yet
430 int cache_index = decode_cpcache_index(which, true);
431 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
432 return e->has_method_type();
433 }
435 oop ConstantPool::method_type_at_if_loaded(constantPoolHandle cpool, int which) {
436 if (cpool->cache() == NULL) return NULL; // nothing to load yet
437 int cache_index = decode_cpcache_index(which, true);
438 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
439 return e->method_type_if_resolved(cpool);
440 }
443 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
444 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
445 return symbol_at(name_index);
446 }
449 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
450 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
451 return symbol_at(signature_index);
452 }
455 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
456 int i = which;
457 if (!uncached && cache() != NULL) {
458 if (ConstantPool::is_invokedynamic_index(which)) {
459 // Invokedynamic index is index into resolved_references
460 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
461 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
462 assert(tag_at(pool_index).is_name_and_type(), "");
463 return pool_index;
464 }
465 // change byte-ordering and go via cache
466 i = remap_instruction_operand_from_cache(which);
467 } else {
468 if (tag_at(which).is_invoke_dynamic()) {
469 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
470 assert(tag_at(pool_index).is_name_and_type(), "");
471 return pool_index;
472 }
473 }
474 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
475 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
476 jint ref_index = *int_at_addr(i);
477 return extract_high_short_from_int(ref_index);
478 }
481 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
482 guarantee(!ConstantPool::is_invokedynamic_index(which),
483 "an invokedynamic instruction does not have a klass");
484 int i = which;
485 if (!uncached && cache() != NULL) {
486 // change byte-ordering and go via cache
487 i = remap_instruction_operand_from_cache(which);
488 }
489 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
490 jint ref_index = *int_at_addr(i);
491 return extract_low_short_from_int(ref_index);
492 }
496 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
497 int cpc_index = operand;
498 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
499 assert((int)(u2)cpc_index == cpc_index, "clean u2");
500 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
501 return member_index;
502 }
505 void ConstantPool::verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle k, TRAPS) {
506 if (k->oop_is_instance() || k->oop_is_objArray()) {
507 instanceKlassHandle holder (THREAD, this_oop->pool_holder());
508 Klass* elem_oop = k->oop_is_instance() ? k() : ObjArrayKlass::cast(k())->bottom_klass();
509 KlassHandle element (THREAD, elem_oop);
511 // The element type could be a typeArray - we only need the access check if it is
512 // an reference to another class
513 if (element->oop_is_instance()) {
514 LinkResolver::check_klass_accessability(holder, element, CHECK);
515 }
516 }
517 }
520 int ConstantPool::name_ref_index_at(int which_nt) {
521 jint ref_index = name_and_type_at(which_nt);
522 return extract_low_short_from_int(ref_index);
523 }
526 int ConstantPool::signature_ref_index_at(int which_nt) {
527 jint ref_index = name_and_type_at(which_nt);
528 return extract_high_short_from_int(ref_index);
529 }
532 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
533 return klass_at(klass_ref_index_at(which), CHECK_NULL);
534 }
537 Symbol* ConstantPool::klass_name_at(int which) {
538 assert(tag_at(which).is_unresolved_klass() || tag_at(which).is_klass(),
539 "Corrupted constant pool");
540 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
541 // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
542 // tag is not updated atomicly.
543 CPSlot entry = slot_at(which);
544 if (entry.is_resolved()) {
545 // Already resolved - return entry's name.
546 assert(entry.get_klass()->is_klass(), "must be");
547 return entry.get_klass()->name();
548 } else {
549 assert(entry.is_unresolved(), "must be either symbol or klass");
550 return entry.get_symbol();
551 }
552 }
554 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
555 jint ref_index = klass_ref_index_at(which);
556 return klass_at_noresolve(ref_index);
557 }
559 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
560 jint ref_index = uncached_klass_ref_index_at(which);
561 return klass_at_noresolve(ref_index);
562 }
564 char* ConstantPool::string_at_noresolve(int which) {
565 Symbol* s = unresolved_string_at(which);
566 if (s == NULL) {
567 return (char*)"<pseudo-string>";
568 } else {
569 return unresolved_string_at(which)->as_C_string();
570 }
571 }
573 BasicType ConstantPool::basic_type_for_signature_at(int which) {
574 return FieldType::basic_type(symbol_at(which));
575 }
578 void ConstantPool::resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS) {
579 for (int index = 1; index < this_oop->length(); index++) { // Index 0 is unused
580 if (this_oop->tag_at(index).is_string()) {
581 this_oop->string_at(index, CHECK);
582 }
583 }
584 }
586 // Resolve all the classes in the constant pool. If they are all resolved,
587 // the constant pool is read-only. Enhancement: allocate cp entries to
588 // another metaspace, and copy to read-only or read-write space if this
589 // bit is set.
590 bool ConstantPool::resolve_class_constants(TRAPS) {
591 constantPoolHandle cp(THREAD, this);
592 for (int index = 1; index < length(); index++) { // Index 0 is unused
593 if (tag_at(index).is_unresolved_klass() &&
594 klass_at_if_loaded(cp, index) == NULL) {
595 return false;
596 }
597 }
598 // set_preresolution(); or some bit for future use
599 return true;
600 }
602 // If resolution for MethodHandle or MethodType fails, save the exception
603 // in the resolution error table, so that the same exception is thrown again.
604 void ConstantPool::save_and_throw_exception(constantPoolHandle this_oop, int which,
605 int tag, TRAPS) {
606 ResourceMark rm;
607 Symbol* error = PENDING_EXCEPTION->klass()->name();
608 MonitorLockerEx ml(this_oop->lock()); // lock cpool to change tag.
610 int error_tag = (tag == JVM_CONSTANT_MethodHandle) ?
611 JVM_CONSTANT_MethodHandleInError : JVM_CONSTANT_MethodTypeInError;
613 if (!PENDING_EXCEPTION->
614 is_a(SystemDictionary::LinkageError_klass())) {
615 // Just throw the exception and don't prevent these classes from
616 // being loaded due to virtual machine errors like StackOverflow
617 // and OutOfMemoryError, etc, or if the thread was hit by stop()
618 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
620 } else if (this_oop->tag_at(which).value() != error_tag) {
621 SystemDictionary::add_resolution_error(this_oop, which, error);
622 this_oop->tag_at_put(which, error_tag);
623 } else {
624 // some other thread has put the class in error state.
625 error = SystemDictionary::find_resolution_error(this_oop, which);
626 assert(error != NULL, "checking");
627 CLEAR_PENDING_EXCEPTION;
628 THROW_MSG(error, "");
629 }
630 }
633 // Called to resolve constants in the constant pool and return an oop.
634 // Some constant pool entries cache their resolved oop. This is also
635 // called to create oops from constants to use in arguments for invokedynamic
636 oop ConstantPool::resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS) {
637 oop result_oop = NULL;
638 Handle throw_exception;
640 if (cache_index == _possible_index_sentinel) {
641 // It is possible that this constant is one which is cached in the objects.
642 // We'll do a linear search. This should be OK because this usage is rare.
643 assert(index > 0, "valid index");
644 cache_index = this_oop->cp_to_object_index(index);
645 }
646 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
647 assert(index == _no_index_sentinel || index >= 0, "");
649 if (cache_index >= 0) {
650 result_oop = this_oop->resolved_references()->obj_at(cache_index);
651 if (result_oop != NULL) {
652 return result_oop;
653 // That was easy...
654 }
655 index = this_oop->object_to_cp_index(cache_index);
656 }
658 jvalue prim_value; // temp used only in a few cases below
660 int tag_value = this_oop->tag_at(index).value();
662 switch (tag_value) {
664 case JVM_CONSTANT_UnresolvedClass:
665 case JVM_CONSTANT_UnresolvedClassInError:
666 case JVM_CONSTANT_Class:
667 {
668 assert(cache_index == _no_index_sentinel, "should not have been set");
669 Klass* resolved = klass_at_impl(this_oop, index, CHECK_NULL);
670 // ldc wants the java mirror.
671 result_oop = resolved->java_mirror();
672 break;
673 }
675 case JVM_CONSTANT_String:
676 assert(cache_index != _no_index_sentinel, "should have been set");
677 if (this_oop->is_pseudo_string_at(index)) {
678 result_oop = this_oop->pseudo_string_at(index, cache_index);
679 break;
680 }
681 result_oop = string_at_impl(this_oop, index, cache_index, CHECK_NULL);
682 break;
684 case JVM_CONSTANT_MethodHandleInError:
685 case JVM_CONSTANT_MethodTypeInError:
686 {
687 Symbol* error = SystemDictionary::find_resolution_error(this_oop, index);
688 guarantee(error != (Symbol*)NULL, "tag mismatch with resolution error table");
689 ResourceMark rm;
690 THROW_MSG_0(error, "");
691 break;
692 }
694 case JVM_CONSTANT_MethodHandle:
695 {
696 int ref_kind = this_oop->method_handle_ref_kind_at(index);
697 int callee_index = this_oop->method_handle_klass_index_at(index);
698 Symbol* name = this_oop->method_handle_name_ref_at(index);
699 Symbol* signature = this_oop->method_handle_signature_ref_at(index);
700 if (PrintMiscellaneous)
701 tty->print_cr("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
702 ref_kind, index, this_oop->method_handle_index_at(index),
703 callee_index, name->as_C_string(), signature->as_C_string());
704 KlassHandle callee;
705 { Klass* k = klass_at_impl(this_oop, callee_index, CHECK_NULL);
706 callee = KlassHandle(THREAD, k);
707 }
708 KlassHandle klass(THREAD, this_oop->pool_holder());
709 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
710 callee, name, signature,
711 THREAD);
712 result_oop = value();
713 if (HAS_PENDING_EXCEPTION) {
714 save_and_throw_exception(this_oop, index, tag_value, CHECK_NULL);
715 }
716 break;
717 }
719 case JVM_CONSTANT_MethodType:
720 {
721 Symbol* signature = this_oop->method_type_signature_at(index);
722 if (PrintMiscellaneous)
723 tty->print_cr("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
724 index, this_oop->method_type_index_at(index),
725 signature->as_C_string());
726 KlassHandle klass(THREAD, this_oop->pool_holder());
727 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
728 result_oop = value();
729 if (HAS_PENDING_EXCEPTION) {
730 save_and_throw_exception(this_oop, index, tag_value, CHECK_NULL);
731 }
732 break;
733 }
735 case JVM_CONSTANT_Integer:
736 assert(cache_index == _no_index_sentinel, "should not have been set");
737 prim_value.i = this_oop->int_at(index);
738 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
739 break;
741 case JVM_CONSTANT_Float:
742 assert(cache_index == _no_index_sentinel, "should not have been set");
743 prim_value.f = this_oop->float_at(index);
744 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
745 break;
747 case JVM_CONSTANT_Long:
748 assert(cache_index == _no_index_sentinel, "should not have been set");
749 prim_value.j = this_oop->long_at(index);
750 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
751 break;
753 case JVM_CONSTANT_Double:
754 assert(cache_index == _no_index_sentinel, "should not have been set");
755 prim_value.d = this_oop->double_at(index);
756 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
757 break;
759 default:
760 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
761 this_oop(), index, cache_index, tag_value) );
762 assert(false, "unexpected constant tag");
763 break;
764 }
766 if (cache_index >= 0) {
767 // Cache the oop here also.
768 Handle result_handle(THREAD, result_oop);
769 MonitorLockerEx ml(this_oop->lock()); // don't know if we really need this
770 oop result = this_oop->resolved_references()->obj_at(cache_index);
771 // Benign race condition: resolved_references may already be filled in while we were trying to lock.
772 // The important thing here is that all threads pick up the same result.
773 // It doesn't matter which racing thread wins, as long as only one
774 // result is used by all threads, and all future queries.
775 // That result may be either a resolved constant or a failure exception.
776 if (result == NULL) {
777 this_oop->resolved_references()->obj_at_put(cache_index, result_handle());
778 return result_handle();
779 } else {
780 // Return the winning thread's result. This can be different than
781 // result_handle() for MethodHandles.
782 return result;
783 }
784 } else {
785 return result_oop;
786 }
787 }
789 oop ConstantPool::uncached_string_at(int which, TRAPS) {
790 Symbol* sym = unresolved_string_at(which);
791 oop str = StringTable::intern(sym, CHECK_(NULL));
792 assert(java_lang_String::is_instance(str), "must be string");
793 return str;
794 }
797 oop ConstantPool::resolve_bootstrap_specifier_at_impl(constantPoolHandle this_oop, int index, TRAPS) {
798 assert(this_oop->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
800 Handle bsm;
801 int argc;
802 {
803 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
804 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
805 // It is accompanied by the optional arguments.
806 int bsm_index = this_oop->invoke_dynamic_bootstrap_method_ref_index_at(index);
807 oop bsm_oop = this_oop->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
808 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
809 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
810 }
812 // Extract the optional static arguments.
813 argc = this_oop->invoke_dynamic_argument_count_at(index);
814 if (argc == 0) return bsm_oop;
816 bsm = Handle(THREAD, bsm_oop);
817 }
819 objArrayHandle info;
820 {
821 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
822 info = objArrayHandle(THREAD, info_oop);
823 }
825 info->obj_at_put(0, bsm());
826 for (int i = 0; i < argc; i++) {
827 int arg_index = this_oop->invoke_dynamic_argument_index_at(index, i);
828 oop arg_oop = this_oop->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
829 info->obj_at_put(1+i, arg_oop);
830 }
832 return info();
833 }
835 oop ConstantPool::string_at_impl(constantPoolHandle this_oop, int which, int obj_index, TRAPS) {
836 // If the string has already been interned, this entry will be non-null
837 oop str = this_oop->resolved_references()->obj_at(obj_index);
838 if (str != NULL) return str;
839 Symbol* sym = this_oop->unresolved_string_at(which);
840 str = StringTable::intern(sym, CHECK_(NULL));
841 this_oop->string_at_put(which, obj_index, str);
842 assert(java_lang_String::is_instance(str), "must be string");
843 return str;
844 }
847 bool ConstantPool::klass_name_at_matches(instanceKlassHandle k,
848 int which) {
849 // Names are interned, so we can compare Symbol*s directly
850 Symbol* cp_name = klass_name_at(which);
851 return (cp_name == k->name());
852 }
855 // Iterate over symbols and decrement ones which are Symbol*s.
856 // This is done during GC so do not need to lock constantPool unless we
857 // have per-thread safepoints.
858 // Only decrement the UTF8 symbols. Unresolved classes and strings point to
859 // these symbols but didn't increment the reference count.
860 void ConstantPool::unreference_symbols() {
861 for (int index = 1; index < length(); index++) { // Index 0 is unused
862 constantTag tag = tag_at(index);
863 if (tag.is_symbol()) {
864 symbol_at(index)->decrement_refcount();
865 }
866 }
867 }
870 // Compare this constant pool's entry at index1 to the constant pool
871 // cp2's entry at index2.
872 bool ConstantPool::compare_entry_to(int index1, constantPoolHandle cp2,
873 int index2, TRAPS) {
875 // The error tags are equivalent to non-error tags when comparing
876 jbyte t1 = tag_at(index1).non_error_value();
877 jbyte t2 = cp2->tag_at(index2).non_error_value();
879 if (t1 != t2) {
880 // Not the same entry type so there is nothing else to check. Note
881 // that this style of checking will consider resolved/unresolved
882 // class pairs as different.
883 // From the ConstantPool* API point of view, this is correct
884 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
885 // plays out in the context of ConstantPool* merging.
886 return false;
887 }
889 switch (t1) {
890 case JVM_CONSTANT_Class:
891 {
892 Klass* k1 = klass_at(index1, CHECK_false);
893 Klass* k2 = cp2->klass_at(index2, CHECK_false);
894 if (k1 == k2) {
895 return true;
896 }
897 } break;
899 case JVM_CONSTANT_ClassIndex:
900 {
901 int recur1 = klass_index_at(index1);
902 int recur2 = cp2->klass_index_at(index2);
903 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
904 if (match) {
905 return true;
906 }
907 } break;
909 case JVM_CONSTANT_Double:
910 {
911 jdouble d1 = double_at(index1);
912 jdouble d2 = cp2->double_at(index2);
913 if (d1 == d2) {
914 return true;
915 }
916 } break;
918 case JVM_CONSTANT_Fieldref:
919 case JVM_CONSTANT_InterfaceMethodref:
920 case JVM_CONSTANT_Methodref:
921 {
922 int recur1 = uncached_klass_ref_index_at(index1);
923 int recur2 = cp2->uncached_klass_ref_index_at(index2);
924 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
925 if (match) {
926 recur1 = uncached_name_and_type_ref_index_at(index1);
927 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
928 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
929 if (match) {
930 return true;
931 }
932 }
933 } break;
935 case JVM_CONSTANT_Float:
936 {
937 jfloat f1 = float_at(index1);
938 jfloat f2 = cp2->float_at(index2);
939 if (f1 == f2) {
940 return true;
941 }
942 } break;
944 case JVM_CONSTANT_Integer:
945 {
946 jint i1 = int_at(index1);
947 jint i2 = cp2->int_at(index2);
948 if (i1 == i2) {
949 return true;
950 }
951 } break;
953 case JVM_CONSTANT_Long:
954 {
955 jlong l1 = long_at(index1);
956 jlong l2 = cp2->long_at(index2);
957 if (l1 == l2) {
958 return true;
959 }
960 } break;
962 case JVM_CONSTANT_NameAndType:
963 {
964 int recur1 = name_ref_index_at(index1);
965 int recur2 = cp2->name_ref_index_at(index2);
966 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
967 if (match) {
968 recur1 = signature_ref_index_at(index1);
969 recur2 = cp2->signature_ref_index_at(index2);
970 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
971 if (match) {
972 return true;
973 }
974 }
975 } break;
977 case JVM_CONSTANT_StringIndex:
978 {
979 int recur1 = string_index_at(index1);
980 int recur2 = cp2->string_index_at(index2);
981 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
982 if (match) {
983 return true;
984 }
985 } break;
987 case JVM_CONSTANT_UnresolvedClass:
988 {
989 Symbol* k1 = unresolved_klass_at(index1);
990 Symbol* k2 = cp2->unresolved_klass_at(index2);
991 if (k1 == k2) {
992 return true;
993 }
994 } break;
996 case JVM_CONSTANT_MethodType:
997 {
998 int k1 = method_type_index_at_error_ok(index1);
999 int k2 = cp2->method_type_index_at_error_ok(index2);
1000 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1001 if (match) {
1002 return true;
1003 }
1004 } break;
1006 case JVM_CONSTANT_MethodHandle:
1007 {
1008 int k1 = method_handle_ref_kind_at_error_ok(index1);
1009 int k2 = cp2->method_handle_ref_kind_at_error_ok(index2);
1010 if (k1 == k2) {
1011 int i1 = method_handle_index_at_error_ok(index1);
1012 int i2 = cp2->method_handle_index_at_error_ok(index2);
1013 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1014 if (match) {
1015 return true;
1016 }
1017 }
1018 } break;
1020 case JVM_CONSTANT_InvokeDynamic:
1021 {
1022 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1023 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1024 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1025 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1026 // separate statements and variables because CHECK_false is used
1027 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1028 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1029 return (match_entry && match_operand);
1030 } break;
1032 case JVM_CONSTANT_String:
1033 {
1034 Symbol* s1 = unresolved_string_at(index1);
1035 Symbol* s2 = cp2->unresolved_string_at(index2);
1036 if (s1 == s2) {
1037 return true;
1038 }
1039 } break;
1041 case JVM_CONSTANT_Utf8:
1042 {
1043 Symbol* s1 = symbol_at(index1);
1044 Symbol* s2 = cp2->symbol_at(index2);
1045 if (s1 == s2) {
1046 return true;
1047 }
1048 } break;
1050 // Invalid is used as the tag for the second constant pool entry
1051 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1052 // not be seen by itself.
1053 case JVM_CONSTANT_Invalid: // fall through
1055 default:
1056 ShouldNotReachHere();
1057 break;
1058 }
1060 return false;
1061 } // end compare_entry_to()
1064 // Resize the operands array with delta_len and delta_size.
1065 // Used in RedefineClasses for CP merge.
1066 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1067 int old_len = operand_array_length(operands());
1068 int new_len = old_len + delta_len;
1069 int min_len = (delta_len > 0) ? old_len : new_len;
1071 int old_size = operands()->length();
1072 int new_size = old_size + delta_size;
1073 int min_size = (delta_size > 0) ? old_size : new_size;
1075 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1076 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1078 // Set index in the resized array for existing elements only
1079 for (int idx = 0; idx < min_len; idx++) {
1080 int offset = operand_offset_at(idx); // offset in original array
1081 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1082 }
1083 // Copy the bootstrap specifiers only
1084 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1085 new_ops->adr_at(2*new_len),
1086 (min_size - 2*min_len) * sizeof(u2));
1087 // Explicitly deallocate old operands array.
1088 // Note, it is not needed for 7u backport.
1089 if ( operands() != NULL) { // the safety check
1090 MetadataFactory::free_array<u2>(loader_data, operands());
1091 }
1092 set_operands(new_ops);
1093 } // end resize_operands()
1096 // Extend the operands array with the length and size of the ext_cp operands.
1097 // Used in RedefineClasses for CP merge.
1098 void ConstantPool::extend_operands(constantPoolHandle ext_cp, TRAPS) {
1099 int delta_len = operand_array_length(ext_cp->operands());
1100 if (delta_len == 0) {
1101 return; // nothing to do
1102 }
1103 int delta_size = ext_cp->operands()->length();
1105 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1107 if (operand_array_length(operands()) == 0) {
1108 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1109 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1110 // The first element index defines the offset of second part
1111 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1112 set_operands(new_ops);
1113 } else {
1114 resize_operands(delta_len, delta_size, CHECK);
1115 }
1117 } // end extend_operands()
1120 // Shrink the operands array to a smaller array with new_len length.
1121 // Used in RedefineClasses for CP merge.
1122 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1123 int old_len = operand_array_length(operands());
1124 if (new_len == old_len) {
1125 return; // nothing to do
1126 }
1127 assert(new_len < old_len, "shrunken operands array must be smaller");
1129 int free_base = operand_next_offset_at(new_len - 1);
1130 int delta_len = new_len - old_len;
1131 int delta_size = 2*delta_len + free_base - operands()->length();
1133 resize_operands(delta_len, delta_size, CHECK);
1135 } // end shrink_operands()
1138 void ConstantPool::copy_operands(constantPoolHandle from_cp,
1139 constantPoolHandle to_cp,
1140 TRAPS) {
1142 int from_oplen = operand_array_length(from_cp->operands());
1143 int old_oplen = operand_array_length(to_cp->operands());
1144 if (from_oplen != 0) {
1145 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1146 // append my operands to the target's operands array
1147 if (old_oplen == 0) {
1148 // Can't just reuse from_cp's operand list because of deallocation issues
1149 int len = from_cp->operands()->length();
1150 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1151 Copy::conjoint_memory_atomic(
1152 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1153 to_cp->set_operands(new_ops);
1154 } else {
1155 int old_len = to_cp->operands()->length();
1156 int from_len = from_cp->operands()->length();
1157 int old_off = old_oplen * sizeof(u2);
1158 int from_off = from_oplen * sizeof(u2);
1159 // Use the metaspace for the destination constant pool
1160 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1161 int fillp = 0, len = 0;
1162 // first part of dest
1163 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1164 new_operands->adr_at(fillp),
1165 (len = old_off) * sizeof(u2));
1166 fillp += len;
1167 // first part of src
1168 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1169 new_operands->adr_at(fillp),
1170 (len = from_off) * sizeof(u2));
1171 fillp += len;
1172 // second part of dest
1173 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1174 new_operands->adr_at(fillp),
1175 (len = old_len - old_off) * sizeof(u2));
1176 fillp += len;
1177 // second part of src
1178 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1179 new_operands->adr_at(fillp),
1180 (len = from_len - from_off) * sizeof(u2));
1181 fillp += len;
1182 assert(fillp == new_operands->length(), "");
1184 // Adjust indexes in the first part of the copied operands array.
1185 for (int j = 0; j < from_oplen; j++) {
1186 int offset = operand_offset_at(new_operands, old_oplen + j);
1187 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1188 offset += old_len; // every new tuple is preceded by old_len extra u2's
1189 operand_offset_at_put(new_operands, old_oplen + j, offset);
1190 }
1192 // replace target operands array with combined array
1193 to_cp->set_operands(new_operands);
1194 }
1195 }
1196 } // end copy_operands()
1199 // Copy this constant pool's entries at start_i to end_i (inclusive)
1200 // to the constant pool to_cp's entries starting at to_i. A total of
1201 // (end_i - start_i) + 1 entries are copied.
1202 void ConstantPool::copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i,
1203 constantPoolHandle to_cp, int to_i, TRAPS) {
1206 int dest_i = to_i; // leave original alone for debug purposes
1208 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1209 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1211 switch (from_cp->tag_at(src_i).value()) {
1212 case JVM_CONSTANT_Double:
1213 case JVM_CONSTANT_Long:
1214 // double and long take two constant pool entries
1215 src_i += 2;
1216 dest_i += 2;
1217 break;
1219 default:
1220 // all others take one constant pool entry
1221 src_i++;
1222 dest_i++;
1223 break;
1224 }
1225 }
1226 copy_operands(from_cp, to_cp, CHECK);
1228 } // end copy_cp_to_impl()
1231 // Copy this constant pool's entry at from_i to the constant pool
1232 // to_cp's entry at to_i.
1233 void ConstantPool::copy_entry_to(constantPoolHandle from_cp, int from_i,
1234 constantPoolHandle to_cp, int to_i,
1235 TRAPS) {
1237 int tag = from_cp->tag_at(from_i).value();
1238 switch (tag) {
1239 case JVM_CONSTANT_Class:
1240 {
1241 Klass* k = from_cp->klass_at(from_i, CHECK);
1242 to_cp->klass_at_put(to_i, k);
1243 } break;
1245 case JVM_CONSTANT_ClassIndex:
1246 {
1247 jint ki = from_cp->klass_index_at(from_i);
1248 to_cp->klass_index_at_put(to_i, ki);
1249 } break;
1251 case JVM_CONSTANT_Double:
1252 {
1253 jdouble d = from_cp->double_at(from_i);
1254 to_cp->double_at_put(to_i, d);
1255 // double takes two constant pool entries so init second entry's tag
1256 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1257 } break;
1259 case JVM_CONSTANT_Fieldref:
1260 {
1261 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1262 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1263 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1264 } break;
1266 case JVM_CONSTANT_Float:
1267 {
1268 jfloat f = from_cp->float_at(from_i);
1269 to_cp->float_at_put(to_i, f);
1270 } break;
1272 case JVM_CONSTANT_Integer:
1273 {
1274 jint i = from_cp->int_at(from_i);
1275 to_cp->int_at_put(to_i, i);
1276 } break;
1278 case JVM_CONSTANT_InterfaceMethodref:
1279 {
1280 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1281 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1282 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1283 } break;
1285 case JVM_CONSTANT_Long:
1286 {
1287 jlong l = from_cp->long_at(from_i);
1288 to_cp->long_at_put(to_i, l);
1289 // long takes two constant pool entries so init second entry's tag
1290 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1291 } break;
1293 case JVM_CONSTANT_Methodref:
1294 {
1295 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1296 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1297 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1298 } break;
1300 case JVM_CONSTANT_NameAndType:
1301 {
1302 int name_ref_index = from_cp->name_ref_index_at(from_i);
1303 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1304 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1305 } break;
1307 case JVM_CONSTANT_StringIndex:
1308 {
1309 jint si = from_cp->string_index_at(from_i);
1310 to_cp->string_index_at_put(to_i, si);
1311 } break;
1313 case JVM_CONSTANT_UnresolvedClass:
1314 case JVM_CONSTANT_UnresolvedClassInError:
1315 {
1316 // Can be resolved after checking tag, so check the slot first.
1317 CPSlot entry = from_cp->slot_at(from_i);
1318 if (entry.is_resolved()) {
1319 assert(entry.get_klass()->is_klass(), "must be");
1320 // Already resolved
1321 to_cp->klass_at_put(to_i, entry.get_klass());
1322 } else {
1323 to_cp->unresolved_klass_at_put(to_i, entry.get_symbol());
1324 }
1325 } break;
1327 case JVM_CONSTANT_String:
1328 {
1329 Symbol* s = from_cp->unresolved_string_at(from_i);
1330 to_cp->unresolved_string_at_put(to_i, s);
1331 } break;
1333 case JVM_CONSTANT_Utf8:
1334 {
1335 Symbol* s = from_cp->symbol_at(from_i);
1336 // Need to increase refcount, the old one will be thrown away and deferenced
1337 s->increment_refcount();
1338 to_cp->symbol_at_put(to_i, s);
1339 } break;
1341 case JVM_CONSTANT_MethodType:
1342 case JVM_CONSTANT_MethodTypeInError:
1343 {
1344 jint k = from_cp->method_type_index_at_error_ok(from_i);
1345 to_cp->method_type_index_at_put(to_i, k);
1346 } break;
1348 case JVM_CONSTANT_MethodHandle:
1349 case JVM_CONSTANT_MethodHandleInError:
1350 {
1351 int k1 = from_cp->method_handle_ref_kind_at_error_ok(from_i);
1352 int k2 = from_cp->method_handle_index_at_error_ok(from_i);
1353 to_cp->method_handle_index_at_put(to_i, k1, k2);
1354 } break;
1356 case JVM_CONSTANT_InvokeDynamic:
1357 {
1358 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1359 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1360 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1361 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1362 } break;
1364 // Invalid is used as the tag for the second constant pool entry
1365 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1366 // not be seen by itself.
1367 case JVM_CONSTANT_Invalid: // fall through
1369 default:
1370 {
1371 ShouldNotReachHere();
1372 } break;
1373 }
1374 } // end copy_entry_to()
1377 // Search constant pool search_cp for an entry that matches this
1378 // constant pool's entry at pattern_i. Returns the index of a
1379 // matching entry or zero (0) if there is no matching entry.
1380 int ConstantPool::find_matching_entry(int pattern_i,
1381 constantPoolHandle search_cp, TRAPS) {
1383 // index zero (0) is not used
1384 for (int i = 1; i < search_cp->length(); i++) {
1385 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1386 if (found) {
1387 return i;
1388 }
1389 }
1391 return 0; // entry not found; return unused index zero (0)
1392 } // end find_matching_entry()
1395 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1396 // cp2's bootstrap specifier at idx2.
1397 bool ConstantPool::compare_operand_to(int idx1, constantPoolHandle cp2, int idx2, TRAPS) {
1398 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1399 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1400 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1402 if (!match) {
1403 return false;
1404 }
1405 int argc = operand_argument_count_at(idx1);
1406 if (argc == cp2->operand_argument_count_at(idx2)) {
1407 for (int j = 0; j < argc; j++) {
1408 k1 = operand_argument_index_at(idx1, j);
1409 k2 = cp2->operand_argument_index_at(idx2, j);
1410 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1411 if (!match) {
1412 return false;
1413 }
1414 }
1415 return true; // got through loop; all elements equal
1416 }
1417 return false;
1418 } // end compare_operand_to()
1420 // Search constant pool search_cp for a bootstrap specifier that matches
1421 // this constant pool's bootstrap specifier at pattern_i index.
1422 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1423 int ConstantPool::find_matching_operand(int pattern_i,
1424 constantPoolHandle search_cp, int search_len, TRAPS) {
1425 for (int i = 0; i < search_len; i++) {
1426 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1427 if (found) {
1428 return i;
1429 }
1430 }
1431 return -1; // bootstrap specifier not found; return unused index (-1)
1432 } // end find_matching_operand()
1435 #ifndef PRODUCT
1437 const char* ConstantPool::printable_name_at(int which) {
1439 constantTag tag = tag_at(which);
1441 if (tag.is_string()) {
1442 return string_at_noresolve(which);
1443 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1444 return klass_name_at(which)->as_C_string();
1445 } else if (tag.is_symbol()) {
1446 return symbol_at(which)->as_C_string();
1447 }
1448 return "";
1449 }
1451 #endif // PRODUCT
1454 // JVMTI GetConstantPool support
1456 // For debugging of constant pool
1457 const bool debug_cpool = false;
1459 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1461 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1462 const char* WARN_MSG = "Must not be such entry!";
1463 jint size = 0;
1464 u2 idx1, idx2;
1466 for (jint idx = 1; idx < cnt; idx++) {
1467 jint ent_size = 0;
1468 u1 tag = *bytes++;
1469 size++; // count tag
1471 printf("const #%03d, tag: %02d ", idx, tag);
1472 switch(tag) {
1473 case JVM_CONSTANT_Invalid: {
1474 printf("Invalid");
1475 break;
1476 }
1477 case JVM_CONSTANT_Unicode: {
1478 printf("Unicode %s", WARN_MSG);
1479 break;
1480 }
1481 case JVM_CONSTANT_Utf8: {
1482 u2 len = Bytes::get_Java_u2(bytes);
1483 char str[128];
1484 if (len > 127) {
1485 len = 127;
1486 }
1487 strncpy(str, (char *) (bytes+2), len);
1488 str[len] = '\0';
1489 printf("Utf8 \"%s\"", str);
1490 ent_size = 2 + len;
1491 break;
1492 }
1493 case JVM_CONSTANT_Integer: {
1494 u4 val = Bytes::get_Java_u4(bytes);
1495 printf("int %d", *(int *) &val);
1496 ent_size = 4;
1497 break;
1498 }
1499 case JVM_CONSTANT_Float: {
1500 u4 val = Bytes::get_Java_u4(bytes);
1501 printf("float %5.3ff", *(float *) &val);
1502 ent_size = 4;
1503 break;
1504 }
1505 case JVM_CONSTANT_Long: {
1506 u8 val = Bytes::get_Java_u8(bytes);
1507 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1508 ent_size = 8;
1509 idx++; // Long takes two cpool slots
1510 break;
1511 }
1512 case JVM_CONSTANT_Double: {
1513 u8 val = Bytes::get_Java_u8(bytes);
1514 printf("double %5.3fd", *(jdouble *)&val);
1515 ent_size = 8;
1516 idx++; // Double takes two cpool slots
1517 break;
1518 }
1519 case JVM_CONSTANT_Class: {
1520 idx1 = Bytes::get_Java_u2(bytes);
1521 printf("class #%03d", idx1);
1522 ent_size = 2;
1523 break;
1524 }
1525 case JVM_CONSTANT_String: {
1526 idx1 = Bytes::get_Java_u2(bytes);
1527 printf("String #%03d", idx1);
1528 ent_size = 2;
1529 break;
1530 }
1531 case JVM_CONSTANT_Fieldref: {
1532 idx1 = Bytes::get_Java_u2(bytes);
1533 idx2 = Bytes::get_Java_u2(bytes+2);
1534 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1535 ent_size = 4;
1536 break;
1537 }
1538 case JVM_CONSTANT_Methodref: {
1539 idx1 = Bytes::get_Java_u2(bytes);
1540 idx2 = Bytes::get_Java_u2(bytes+2);
1541 printf("Method #%03d, #%03d", idx1, idx2);
1542 ent_size = 4;
1543 break;
1544 }
1545 case JVM_CONSTANT_InterfaceMethodref: {
1546 idx1 = Bytes::get_Java_u2(bytes);
1547 idx2 = Bytes::get_Java_u2(bytes+2);
1548 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1549 ent_size = 4;
1550 break;
1551 }
1552 case JVM_CONSTANT_NameAndType: {
1553 idx1 = Bytes::get_Java_u2(bytes);
1554 idx2 = Bytes::get_Java_u2(bytes+2);
1555 printf("NameAndType #%03d, #%03d", idx1, idx2);
1556 ent_size = 4;
1557 break;
1558 }
1559 case JVM_CONSTANT_ClassIndex: {
1560 printf("ClassIndex %s", WARN_MSG);
1561 break;
1562 }
1563 case JVM_CONSTANT_UnresolvedClass: {
1564 printf("UnresolvedClass: %s", WARN_MSG);
1565 break;
1566 }
1567 case JVM_CONSTANT_UnresolvedClassInError: {
1568 printf("UnresolvedClassInErr: %s", WARN_MSG);
1569 break;
1570 }
1571 case JVM_CONSTANT_StringIndex: {
1572 printf("StringIndex: %s", WARN_MSG);
1573 break;
1574 }
1575 }
1576 printf(";\n");
1577 bytes += ent_size;
1578 size += ent_size;
1579 }
1580 printf("Cpool size: %d\n", size);
1581 fflush(0);
1582 return;
1583 } /* end print_cpool_bytes */
1586 // Returns size of constant pool entry.
1587 jint ConstantPool::cpool_entry_size(jint idx) {
1588 switch(tag_at(idx).value()) {
1589 case JVM_CONSTANT_Invalid:
1590 case JVM_CONSTANT_Unicode:
1591 return 1;
1593 case JVM_CONSTANT_Utf8:
1594 return 3 + symbol_at(idx)->utf8_length();
1596 case JVM_CONSTANT_Class:
1597 case JVM_CONSTANT_String:
1598 case JVM_CONSTANT_ClassIndex:
1599 case JVM_CONSTANT_UnresolvedClass:
1600 case JVM_CONSTANT_UnresolvedClassInError:
1601 case JVM_CONSTANT_StringIndex:
1602 case JVM_CONSTANT_MethodType:
1603 case JVM_CONSTANT_MethodTypeInError:
1604 return 3;
1606 case JVM_CONSTANT_MethodHandle:
1607 case JVM_CONSTANT_MethodHandleInError:
1608 return 4; //tag, ref_kind, ref_index
1610 case JVM_CONSTANT_Integer:
1611 case JVM_CONSTANT_Float:
1612 case JVM_CONSTANT_Fieldref:
1613 case JVM_CONSTANT_Methodref:
1614 case JVM_CONSTANT_InterfaceMethodref:
1615 case JVM_CONSTANT_NameAndType:
1616 return 5;
1618 case JVM_CONSTANT_InvokeDynamic:
1619 // u1 tag, u2 bsm, u2 nt
1620 return 5;
1622 case JVM_CONSTANT_Long:
1623 case JVM_CONSTANT_Double:
1624 return 9;
1625 }
1626 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1627 return 1;
1628 } /* end cpool_entry_size */
1631 // SymbolHashMap is used to find a constant pool index from a string.
1632 // This function fills in SymbolHashMaps, one for utf8s and one for
1633 // class names, returns size of the cpool raw bytes.
1634 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1635 SymbolHashMap *classmap) {
1636 jint size = 0;
1638 for (u2 idx = 1; idx < length(); idx++) {
1639 u2 tag = tag_at(idx).value();
1640 size += cpool_entry_size(idx);
1642 switch(tag) {
1643 case JVM_CONSTANT_Utf8: {
1644 Symbol* sym = symbol_at(idx);
1645 symmap->add_entry(sym, idx);
1646 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1647 break;
1648 }
1649 case JVM_CONSTANT_Class:
1650 case JVM_CONSTANT_UnresolvedClass:
1651 case JVM_CONSTANT_UnresolvedClassInError: {
1652 Symbol* sym = klass_name_at(idx);
1653 classmap->add_entry(sym, idx);
1654 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1655 break;
1656 }
1657 case JVM_CONSTANT_Long:
1658 case JVM_CONSTANT_Double: {
1659 idx++; // Both Long and Double take two cpool slots
1660 break;
1661 }
1662 }
1663 }
1664 return size;
1665 } /* end hash_utf8_entries_to */
1668 // Copy cpool bytes.
1669 // Returns:
1670 // 0, in case of OutOfMemoryError
1671 // -1, in case of internal error
1672 // > 0, count of the raw cpool bytes that have been copied
1673 int ConstantPool::copy_cpool_bytes(int cpool_size,
1674 SymbolHashMap* tbl,
1675 unsigned char *bytes) {
1676 u2 idx1, idx2;
1677 jint size = 0;
1678 jint cnt = length();
1679 unsigned char *start_bytes = bytes;
1681 for (jint idx = 1; idx < cnt; idx++) {
1682 u1 tag = tag_at(idx).value();
1683 jint ent_size = cpool_entry_size(idx);
1685 assert(size + ent_size <= cpool_size, "Size mismatch");
1687 *bytes = tag;
1688 DBG(printf("#%03hd tag=%03hd, ", idx, tag));
1689 switch(tag) {
1690 case JVM_CONSTANT_Invalid: {
1691 DBG(printf("JVM_CONSTANT_Invalid"));
1692 break;
1693 }
1694 case JVM_CONSTANT_Unicode: {
1695 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1696 DBG(printf("JVM_CONSTANT_Unicode"));
1697 break;
1698 }
1699 case JVM_CONSTANT_Utf8: {
1700 Symbol* sym = symbol_at(idx);
1701 char* str = sym->as_utf8();
1702 // Warning! It's crashing on x86 with len = sym->utf8_length()
1703 int len = (int) strlen(str);
1704 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1705 for (int i = 0; i < len; i++) {
1706 bytes[3+i] = (u1) str[i];
1707 }
1708 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1709 break;
1710 }
1711 case JVM_CONSTANT_Integer: {
1712 jint val = int_at(idx);
1713 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1714 break;
1715 }
1716 case JVM_CONSTANT_Float: {
1717 jfloat val = float_at(idx);
1718 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1719 break;
1720 }
1721 case JVM_CONSTANT_Long: {
1722 jlong val = long_at(idx);
1723 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1724 idx++; // Long takes two cpool slots
1725 break;
1726 }
1727 case JVM_CONSTANT_Double: {
1728 jdouble val = double_at(idx);
1729 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1730 idx++; // Double takes two cpool slots
1731 break;
1732 }
1733 case JVM_CONSTANT_Class:
1734 case JVM_CONSTANT_UnresolvedClass:
1735 case JVM_CONSTANT_UnresolvedClassInError: {
1736 *bytes = JVM_CONSTANT_Class;
1737 Symbol* sym = klass_name_at(idx);
1738 idx1 = tbl->symbol_to_value(sym);
1739 assert(idx1 != 0, "Have not found a hashtable entry");
1740 Bytes::put_Java_u2((address) (bytes+1), idx1);
1741 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1742 break;
1743 }
1744 case JVM_CONSTANT_String: {
1745 *bytes = JVM_CONSTANT_String;
1746 Symbol* sym = unresolved_string_at(idx);
1747 idx1 = tbl->symbol_to_value(sym);
1748 assert(idx1 != 0, "Have not found a hashtable entry");
1749 Bytes::put_Java_u2((address) (bytes+1), idx1);
1750 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1751 break;
1752 }
1753 case JVM_CONSTANT_Fieldref:
1754 case JVM_CONSTANT_Methodref:
1755 case JVM_CONSTANT_InterfaceMethodref: {
1756 idx1 = uncached_klass_ref_index_at(idx);
1757 idx2 = uncached_name_and_type_ref_index_at(idx);
1758 Bytes::put_Java_u2((address) (bytes+1), idx1);
1759 Bytes::put_Java_u2((address) (bytes+3), idx2);
1760 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1761 break;
1762 }
1763 case JVM_CONSTANT_NameAndType: {
1764 idx1 = name_ref_index_at(idx);
1765 idx2 = signature_ref_index_at(idx);
1766 Bytes::put_Java_u2((address) (bytes+1), idx1);
1767 Bytes::put_Java_u2((address) (bytes+3), idx2);
1768 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1769 break;
1770 }
1771 case JVM_CONSTANT_ClassIndex: {
1772 *bytes = JVM_CONSTANT_Class;
1773 idx1 = klass_index_at(idx);
1774 Bytes::put_Java_u2((address) (bytes+1), idx1);
1775 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1776 break;
1777 }
1778 case JVM_CONSTANT_StringIndex: {
1779 *bytes = JVM_CONSTANT_String;
1780 idx1 = string_index_at(idx);
1781 Bytes::put_Java_u2((address) (bytes+1), idx1);
1782 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1783 break;
1784 }
1785 case JVM_CONSTANT_MethodHandle:
1786 case JVM_CONSTANT_MethodHandleInError: {
1787 *bytes = JVM_CONSTANT_MethodHandle;
1788 int kind = method_handle_ref_kind_at_error_ok(idx);
1789 idx1 = method_handle_index_at_error_ok(idx);
1790 *(bytes+1) = (unsigned char) kind;
1791 Bytes::put_Java_u2((address) (bytes+2), idx1);
1792 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1793 break;
1794 }
1795 case JVM_CONSTANT_MethodType:
1796 case JVM_CONSTANT_MethodTypeInError: {
1797 *bytes = JVM_CONSTANT_MethodType;
1798 idx1 = method_type_index_at_error_ok(idx);
1799 Bytes::put_Java_u2((address) (bytes+1), idx1);
1800 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1801 break;
1802 }
1803 case JVM_CONSTANT_InvokeDynamic: {
1804 *bytes = tag;
1805 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1806 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1807 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1808 Bytes::put_Java_u2((address) (bytes+1), idx1);
1809 Bytes::put_Java_u2((address) (bytes+3), idx2);
1810 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1811 break;
1812 }
1813 }
1814 DBG(printf("\n"));
1815 bytes += ent_size;
1816 size += ent_size;
1817 }
1818 assert(size == cpool_size, "Size mismatch");
1820 // Keep temorarily for debugging until it's stable.
1821 DBG(print_cpool_bytes(cnt, start_bytes));
1822 return (int)(bytes - start_bytes);
1823 } /* end copy_cpool_bytes */
1825 #undef DBG
1828 void ConstantPool::set_on_stack(const bool value) {
1829 if (value) {
1830 int old_flags = *const_cast<volatile int *>(&_flags);
1831 while ((old_flags & _on_stack) == 0) {
1832 int new_flags = old_flags | _on_stack;
1833 int result = Atomic::cmpxchg(new_flags, &_flags, old_flags);
1835 if (result == old_flags) {
1836 // Succeeded.
1837 MetadataOnStackMark::record(this, Thread::current());
1838 return;
1839 }
1840 old_flags = result;
1841 }
1842 } else {
1843 // Clearing is done single-threadedly.
1844 _flags &= ~_on_stack;
1845 }
1846 }
1848 // JSR 292 support for patching constant pool oops after the class is linked and
1849 // the oop array for resolved references are created.
1850 // We can't do this during classfile parsing, which is how the other indexes are
1851 // patched. The other patches are applied early for some error checking
1852 // so only defer the pseudo_strings.
1853 void ConstantPool::patch_resolved_references(
1854 GrowableArray<Handle>* cp_patches) {
1855 assert(EnableInvokeDynamic, "");
1856 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
1857 Handle patch = cp_patches->at(index);
1858 if (patch.not_null()) {
1859 assert (tag_at(index).is_string(), "should only be string left");
1860 // Patching a string means pre-resolving it.
1861 // The spelling in the constant pool is ignored.
1862 // The constant reference may be any object whatever.
1863 // If it is not a real interned string, the constant is referred
1864 // to as a "pseudo-string", and must be presented to the CP
1865 // explicitly, because it may require scavenging.
1866 int obj_index = cp_to_object_index(index);
1867 pseudo_string_at_put(index, obj_index, patch());
1868 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
1869 }
1870 }
1871 #ifdef ASSERT
1872 // Ensure that all the patches have been used.
1873 for (int index = 0; index < cp_patches->length(); index++) {
1874 assert(cp_patches->at(index).is_null(),
1875 err_msg("Unused constant pool patch at %d in class file %s",
1876 index,
1877 pool_holder()->external_name()));
1878 }
1879 #endif // ASSERT
1880 }
1882 #ifndef PRODUCT
1884 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
1885 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
1886 guarantee(obj->is_constantPool(), "object must be constant pool");
1887 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
1888 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
1890 for (int i = 0; i< cp->length(); i++) {
1891 if (cp->tag_at(i).is_unresolved_klass()) {
1892 // This will force loading of the class
1893 Klass* klass = cp->klass_at(i, CHECK);
1894 if (klass->oop_is_instance()) {
1895 // Force initialization of class
1896 InstanceKlass::cast(klass)->initialize(CHECK);
1897 }
1898 }
1899 }
1900 }
1902 #endif
1905 // Printing
1907 void ConstantPool::print_on(outputStream* st) const {
1908 EXCEPTION_MARK;
1909 assert(is_constantPool(), "must be constantPool");
1910 st->print_cr("%s", internal_name());
1911 if (flags() != 0) {
1912 st->print(" - flags: 0x%x", flags());
1913 if (has_preresolution()) st->print(" has_preresolution");
1914 if (on_stack()) st->print(" on_stack");
1915 st->cr();
1916 }
1917 if (pool_holder() != NULL) {
1918 st->print_cr(" - holder: " INTPTR_FORMAT, pool_holder());
1919 }
1920 st->print_cr(" - cache: " INTPTR_FORMAT, cache());
1921 st->print_cr(" - resolved_references: " INTPTR_FORMAT, (void *)resolved_references());
1922 st->print_cr(" - reference_map: " INTPTR_FORMAT, reference_map());
1924 for (int index = 1; index < length(); index++) { // Index 0 is unused
1925 ((ConstantPool*)this)->print_entry_on(index, st);
1926 switch (tag_at(index).value()) {
1927 case JVM_CONSTANT_Long :
1928 case JVM_CONSTANT_Double :
1929 index++; // Skip entry following eigth-byte constant
1930 }
1932 }
1933 st->cr();
1934 }
1936 // Print one constant pool entry
1937 void ConstantPool::print_entry_on(const int index, outputStream* st) {
1938 EXCEPTION_MARK;
1939 st->print(" - %3d : ", index);
1940 tag_at(index).print_on(st);
1941 st->print(" : ");
1942 switch (tag_at(index).value()) {
1943 case JVM_CONSTANT_Class :
1944 { Klass* k = klass_at(index, CATCH);
1945 guarantee(k != NULL, "need klass");
1946 k->print_value_on(st);
1947 st->print(" {0x%lx}", (address)k);
1948 }
1949 break;
1950 case JVM_CONSTANT_Fieldref :
1951 case JVM_CONSTANT_Methodref :
1952 case JVM_CONSTANT_InterfaceMethodref :
1953 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
1954 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
1955 break;
1956 case JVM_CONSTANT_String :
1957 if (is_pseudo_string_at(index)) {
1958 oop anObj = pseudo_string_at(index);
1959 anObj->print_value_on(st);
1960 st->print(" {0x%lx}", (address)anObj);
1961 } else {
1962 unresolved_string_at(index)->print_value_on(st);
1963 }
1964 break;
1965 case JVM_CONSTANT_Integer :
1966 st->print("%d", int_at(index));
1967 break;
1968 case JVM_CONSTANT_Float :
1969 st->print("%f", float_at(index));
1970 break;
1971 case JVM_CONSTANT_Long :
1972 st->print_jlong(long_at(index));
1973 break;
1974 case JVM_CONSTANT_Double :
1975 st->print("%lf", double_at(index));
1976 break;
1977 case JVM_CONSTANT_NameAndType :
1978 st->print("name_index=%d", name_ref_index_at(index));
1979 st->print(" signature_index=%d", signature_ref_index_at(index));
1980 break;
1981 case JVM_CONSTANT_Utf8 :
1982 symbol_at(index)->print_value_on(st);
1983 break;
1984 case JVM_CONSTANT_UnresolvedClass : // fall-through
1985 case JVM_CONSTANT_UnresolvedClassInError: {
1986 // unresolved_klass_at requires lock or safe world.
1987 CPSlot entry = slot_at(index);
1988 if (entry.is_resolved()) {
1989 entry.get_klass()->print_value_on(st);
1990 } else {
1991 entry.get_symbol()->print_value_on(st);
1992 }
1993 }
1994 break;
1995 case JVM_CONSTANT_MethodHandle :
1996 case JVM_CONSTANT_MethodHandleInError :
1997 st->print("ref_kind=%d", method_handle_ref_kind_at_error_ok(index));
1998 st->print(" ref_index=%d", method_handle_index_at_error_ok(index));
1999 break;
2000 case JVM_CONSTANT_MethodType :
2001 case JVM_CONSTANT_MethodTypeInError :
2002 st->print("signature_index=%d", method_type_index_at_error_ok(index));
2003 break;
2004 case JVM_CONSTANT_InvokeDynamic :
2005 {
2006 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2007 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2008 int argc = invoke_dynamic_argument_count_at(index);
2009 if (argc > 0) {
2010 for (int arg_i = 0; arg_i < argc; arg_i++) {
2011 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2012 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2013 }
2014 st->print("}");
2015 }
2016 }
2017 break;
2018 default:
2019 ShouldNotReachHere();
2020 break;
2021 }
2022 st->cr();
2023 }
2025 void ConstantPool::print_value_on(outputStream* st) const {
2026 assert(is_constantPool(), "must be constantPool");
2027 st->print("constant pool [%d]", length());
2028 if (has_preresolution()) st->print("/preresolution");
2029 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2030 print_address_on(st);
2031 st->print(" for ");
2032 pool_holder()->print_value_on(st);
2033 if (pool_holder() != NULL) {
2034 bool extra = (pool_holder()->constants() != this);
2035 if (extra) st->print(" (extra)");
2036 }
2037 if (cache() != NULL) {
2038 st->print(" cache=" PTR_FORMAT, cache());
2039 }
2040 }
2042 #if INCLUDE_SERVICES
2043 // Size Statistics
2044 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2045 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2046 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2047 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2048 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2049 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2051 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2052 sz->_cp_refmap_bytes;
2053 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2054 }
2055 #endif // INCLUDE_SERVICES
2057 // Verification
2059 void ConstantPool::verify_on(outputStream* st) {
2060 guarantee(is_constantPool(), "object must be constant pool");
2061 for (int i = 0; i< length(); i++) {
2062 constantTag tag = tag_at(i);
2063 CPSlot entry = slot_at(i);
2064 if (tag.is_klass()) {
2065 if (entry.is_resolved()) {
2066 guarantee(entry.get_klass()->is_klass(), "should be klass");
2067 }
2068 } else if (tag.is_unresolved_klass()) {
2069 if (entry.is_resolved()) {
2070 guarantee(entry.get_klass()->is_klass(), "should be klass");
2071 }
2072 } else if (tag.is_symbol()) {
2073 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2074 } else if (tag.is_string()) {
2075 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2076 }
2077 }
2078 if (cache() != NULL) {
2079 // Note: cache() can be NULL before a class is completely setup or
2080 // in temporary constant pools used during constant pool merging
2081 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2082 }
2083 if (pool_holder() != NULL) {
2084 // Note: pool_holder() can be NULL in temporary constant pools
2085 // used during constant pool merging
2086 guarantee(pool_holder()->is_klass(), "should be klass");
2087 }
2088 }
2091 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2092 char *str = sym->as_utf8();
2093 unsigned int hash = compute_hash(str, sym->utf8_length());
2094 unsigned int index = hash % table_size();
2096 // check if already in map
2097 // we prefer the first entry since it is more likely to be what was used in
2098 // the class file
2099 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2100 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2101 if (en->hash() == hash && en->symbol() == sym) {
2102 return; // already there
2103 }
2104 }
2106 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2107 entry->set_next(bucket(index));
2108 _buckets[index].set_entry(entry);
2109 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2110 }
2112 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2113 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2114 char *str = sym->as_utf8();
2115 int len = sym->utf8_length();
2116 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2117 unsigned int index = hash % table_size();
2118 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2119 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2120 if (en->hash() == hash && en->symbol() == sym) {
2121 return en;
2122 }
2123 }
2124 return NULL;
2125 }