Tue, 15 Apr 2014 17:02:20 -0400
8028497: SIGSEGV at ClassLoaderData::oops_do(OopClosure*, KlassClosure*, bool)
Summary: Keep class in CLD::_klasses list and mirror created for CDS classes if OOM during restore_shareable_info(). This keeps pointers consistent for CMS.
Reviewed-by: ehelin, stefank, jmasa, iklam
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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23 */
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 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
46 // Tags are RW but comment below applies to tags also.
47 Array<u1>* tags = MetadataFactory::new_writeable_array<u1>(loader_data, length, 0, CHECK_NULL);
49 int size = ConstantPool::size(length);
51 // CDS considerations:
52 // Allocate read-write but may be able to move to read-only at dumping time
53 // if all the klasses are resolved. The only other field that is writable is
54 // the resolved_references array, which is recreated at startup time.
55 // But that could be moved to InstanceKlass (although a pain to access from
56 // assembly code). Maybe it could be moved to the cpCache which is RW.
57 return new (loader_data, size, false, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
58 }
60 ConstantPool::ConstantPool(Array<u1>* tags) {
61 set_length(tags->length());
62 set_tags(NULL);
63 set_cache(NULL);
64 set_reference_map(NULL);
65 set_resolved_references(NULL);
66 set_operands(NULL);
67 set_pool_holder(NULL);
68 set_flags(0);
70 // only set to non-zero if constant pool is merged by RedefineClasses
71 set_version(0);
72 set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
74 // initialize tag array
75 int length = tags->length();
76 for (int index = 0; index < length; index++) {
77 tags->at_put(index, JVM_CONSTANT_Invalid);
78 }
79 set_tags(tags);
80 }
82 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
83 MetadataFactory::free_metadata(loader_data, cache());
84 set_cache(NULL);
85 MetadataFactory::free_array<u2>(loader_data, reference_map());
86 set_reference_map(NULL);
88 MetadataFactory::free_array<jushort>(loader_data, operands());
89 set_operands(NULL);
91 release_C_heap_structures();
93 // free tag array
94 MetadataFactory::free_array<u1>(loader_data, tags());
95 set_tags(NULL);
96 }
98 void ConstantPool::release_C_heap_structures() {
99 // walk constant pool and decrement symbol reference counts
100 unreference_symbols();
102 delete _lock;
103 set_lock(NULL);
104 }
106 objArrayOop ConstantPool::resolved_references() const {
107 return (objArrayOop)JNIHandles::resolve(_resolved_references);
108 }
110 // Create resolved_references array and mapping array for original cp indexes
111 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
112 // to map it back for resolving and some unlikely miscellaneous uses.
113 // The objects created by invokedynamic are appended to this list.
114 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
115 intStack reference_map,
116 int constant_pool_map_length,
117 TRAPS) {
118 // Initialized the resolved object cache.
119 int map_length = reference_map.length();
120 if (map_length > 0) {
121 // Only need mapping back to constant pool entries. The map isn't used for
122 // invokedynamic resolved_reference entries. For invokedynamic entries,
123 // the constant pool cache index has the mapping back to both the constant
124 // pool and to the resolved reference index.
125 if (constant_pool_map_length > 0) {
126 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
128 for (int i = 0; i < constant_pool_map_length; i++) {
129 int x = reference_map.at(i);
130 assert(x == (int)(jushort) x, "klass index is too big");
131 om->at_put(i, (jushort)x);
132 }
133 set_reference_map(om);
134 }
136 // Create Java array for holding resolved strings, methodHandles,
137 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
138 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
139 Handle refs_handle (THREAD, (oop)stom); // must handleize.
140 set_resolved_references(loader_data->add_handle(refs_handle));
141 }
142 }
144 // CDS support. Create a new resolved_references array.
145 void ConstantPool::restore_unshareable_info(TRAPS) {
147 // Only create the new resolved references array and lock if it hasn't been
148 // attempted before
149 if (resolved_references() != NULL) return;
151 // restore the C++ vtable from the shared archive
152 restore_vtable();
154 if (SystemDictionary::Object_klass_loaded()) {
155 // Recreate the object array and add to ClassLoaderData.
156 int map_length = resolved_reference_length();
157 if (map_length > 0) {
158 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
159 Handle refs_handle (THREAD, (oop)stom); // must handleize.
161 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
162 set_resolved_references(loader_data->add_handle(refs_handle));
163 }
165 // Also need to recreate the mutex. Make sure this matches the constructor
166 set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
167 }
168 }
170 void ConstantPool::remove_unshareable_info() {
171 // Resolved references are not in the shared archive.
172 // Save the length for restoration. It is not necessarily the same length
173 // as reference_map.length() if invokedynamic is saved.
174 set_resolved_reference_length(
175 resolved_references() != NULL ? resolved_references()->length() : 0);
176 set_resolved_references(NULL);
177 set_lock(NULL);
178 }
180 int ConstantPool::cp_to_object_index(int cp_index) {
181 // this is harder don't do this so much.
182 int i = reference_map()->find(cp_index);
183 // We might not find the index for jsr292 call.
184 return (i < 0) ? _no_index_sentinel : i;
185 }
187 Klass* ConstantPool::klass_at_impl(constantPoolHandle this_oop, int which, TRAPS) {
188 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
189 // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
190 // tag is not updated atomicly.
192 CPSlot entry = this_oop->slot_at(which);
193 if (entry.is_resolved()) {
194 assert(entry.get_klass()->is_klass(), "must be");
195 // Already resolved - return entry.
196 return entry.get_klass();
197 }
199 // Acquire lock on constant oop while doing update. After we get the lock, we check if another object
200 // already has updated the object
201 assert(THREAD->is_Java_thread(), "must be a Java thread");
202 bool do_resolve = false;
203 bool in_error = false;
205 // Create a handle for the mirror. This will preserve the resolved class
206 // until the loader_data is registered.
207 Handle mirror_handle;
209 Symbol* name = NULL;
210 Handle loader;
211 { MonitorLockerEx ml(this_oop->lock());
213 if (this_oop->tag_at(which).is_unresolved_klass()) {
214 if (this_oop->tag_at(which).is_unresolved_klass_in_error()) {
215 in_error = true;
216 } else {
217 do_resolve = true;
218 name = this_oop->unresolved_klass_at(which);
219 loader = Handle(THREAD, this_oop->pool_holder()->class_loader());
220 }
221 }
222 } // unlocking constantPool
225 // The original attempt to resolve this constant pool entry failed so find the
226 // original error and throw it again (JVMS 5.4.3).
227 if (in_error) {
228 Symbol* error = SystemDictionary::find_resolution_error(this_oop, which);
229 guarantee(error != (Symbol*)NULL, "tag mismatch with resolution error table");
230 ResourceMark rm;
231 // exception text will be the class name
232 const char* className = this_oop->unresolved_klass_at(which)->as_C_string();
233 THROW_MSG_0(error, className);
234 }
236 if (do_resolve) {
237 // this_oop must be unlocked during resolve_or_fail
238 oop protection_domain = this_oop->pool_holder()->protection_domain();
239 Handle h_prot (THREAD, protection_domain);
240 Klass* k_oop = SystemDictionary::resolve_or_fail(name, loader, h_prot, true, THREAD);
241 KlassHandle k;
242 if (!HAS_PENDING_EXCEPTION) {
243 k = KlassHandle(THREAD, k_oop);
244 // preserve the resolved klass.
245 mirror_handle = Handle(THREAD, k_oop->java_mirror());
246 // Do access check for klasses
247 verify_constant_pool_resolve(this_oop, k, THREAD);
248 }
250 // Failed to resolve class. We must record the errors so that subsequent attempts
251 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
252 if (HAS_PENDING_EXCEPTION) {
253 ResourceMark rm;
254 Symbol* error = PENDING_EXCEPTION->klass()->name();
256 bool throw_orig_error = false;
257 {
258 MonitorLockerEx ml(this_oop->lock());
260 // some other thread has beaten us and has resolved the class.
261 if (this_oop->tag_at(which).is_klass()) {
262 CLEAR_PENDING_EXCEPTION;
263 entry = this_oop->resolved_klass_at(which);
264 return entry.get_klass();
265 }
267 if (!PENDING_EXCEPTION->
268 is_a(SystemDictionary::LinkageError_klass())) {
269 // Just throw the exception and don't prevent these classes from
270 // being loaded due to virtual machine errors like StackOverflow
271 // and OutOfMemoryError, etc, or if the thread was hit by stop()
272 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
273 }
274 else if (!this_oop->tag_at(which).is_unresolved_klass_in_error()) {
275 SystemDictionary::add_resolution_error(this_oop, which, error);
276 this_oop->tag_at_put(which, JVM_CONSTANT_UnresolvedClassInError);
277 } else {
278 // some other thread has put the class in error state.
279 error = SystemDictionary::find_resolution_error(this_oop, which);
280 assert(error != NULL, "checking");
281 throw_orig_error = true;
282 }
283 } // unlocked
285 if (throw_orig_error) {
286 CLEAR_PENDING_EXCEPTION;
287 ResourceMark rm;
288 const char* className = this_oop->unresolved_klass_at(which)->as_C_string();
289 THROW_MSG_0(error, className);
290 }
292 return 0;
293 }
295 if (TraceClassResolution && !k()->oop_is_array()) {
296 // skip resolving the constant pool so that this code get's
297 // called the next time some bytecodes refer to this class.
298 ResourceMark rm;
299 int line_number = -1;
300 const char * source_file = NULL;
301 if (JavaThread::current()->has_last_Java_frame()) {
302 // try to identify the method which called this function.
303 vframeStream vfst(JavaThread::current());
304 if (!vfst.at_end()) {
305 line_number = vfst.method()->line_number_from_bci(vfst.bci());
306 Symbol* s = vfst.method()->method_holder()->source_file_name();
307 if (s != NULL) {
308 source_file = s->as_C_string();
309 }
310 }
311 }
312 if (k() != this_oop->pool_holder()) {
313 // only print something if the classes are different
314 if (source_file != NULL) {
315 tty->print("RESOLVE %s %s %s:%d\n",
316 this_oop->pool_holder()->external_name(),
317 InstanceKlass::cast(k())->external_name(), source_file, line_number);
318 } else {
319 tty->print("RESOLVE %s %s\n",
320 this_oop->pool_holder()->external_name(),
321 InstanceKlass::cast(k())->external_name());
322 }
323 }
324 return k();
325 } else {
326 MonitorLockerEx ml(this_oop->lock());
327 // Only updated constant pool - if it is resolved.
328 do_resolve = this_oop->tag_at(which).is_unresolved_klass();
329 if (do_resolve) {
330 ClassLoaderData* this_key = this_oop->pool_holder()->class_loader_data();
331 this_key->record_dependency(k(), CHECK_NULL); // Can throw OOM
332 this_oop->klass_at_put(which, k());
333 }
334 }
335 }
337 entry = this_oop->resolved_klass_at(which);
338 assert(entry.is_resolved() && entry.get_klass()->is_klass(), "must be resolved at this point");
339 return entry.get_klass();
340 }
343 // Does not update ConstantPool* - to avoid any exception throwing. Used
344 // by compiler and exception handling. Also used to avoid classloads for
345 // instanceof operations. Returns NULL if the class has not been loaded or
346 // if the verification of constant pool failed
347 Klass* ConstantPool::klass_at_if_loaded(constantPoolHandle this_oop, int which) {
348 CPSlot entry = this_oop->slot_at(which);
349 if (entry.is_resolved()) {
350 assert(entry.get_klass()->is_klass(), "must be");
351 return entry.get_klass();
352 } else {
353 assert(entry.is_unresolved(), "must be either symbol or klass");
354 Thread *thread = Thread::current();
355 Symbol* name = entry.get_symbol();
356 oop loader = this_oop->pool_holder()->class_loader();
357 oop protection_domain = this_oop->pool_holder()->protection_domain();
358 Handle h_prot (thread, protection_domain);
359 Handle h_loader (thread, loader);
360 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
362 if (k != NULL) {
363 // Make sure that resolving is legal
364 EXCEPTION_MARK;
365 KlassHandle klass(THREAD, k);
366 // return NULL if verification fails
367 verify_constant_pool_resolve(this_oop, klass, THREAD);
368 if (HAS_PENDING_EXCEPTION) {
369 CLEAR_PENDING_EXCEPTION;
370 return NULL;
371 }
372 return klass();
373 } else {
374 return k;
375 }
376 }
377 }
380 Klass* ConstantPool::klass_ref_at_if_loaded(constantPoolHandle this_oop, int which) {
381 return klass_at_if_loaded(this_oop, this_oop->klass_ref_index_at(which));
382 }
385 Method* ConstantPool::method_at_if_loaded(constantPoolHandle cpool,
386 int which) {
387 if (cpool->cache() == NULL) return NULL; // nothing to load yet
388 int cache_index = decode_cpcache_index(which, true);
389 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
390 // FIXME: should be an assert
391 if (PrintMiscellaneous && (Verbose||WizardMode)) {
392 tty->print_cr("bad operand %d in:", which); cpool->print();
393 }
394 return NULL;
395 }
396 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
397 return e->method_if_resolved(cpool);
398 }
401 bool ConstantPool::has_appendix_at_if_loaded(constantPoolHandle cpool, int which) {
402 if (cpool->cache() == NULL) return false; // nothing to load yet
403 int cache_index = decode_cpcache_index(which, true);
404 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
405 return e->has_appendix();
406 }
408 oop ConstantPool::appendix_at_if_loaded(constantPoolHandle cpool, int which) {
409 if (cpool->cache() == NULL) return NULL; // nothing to load yet
410 int cache_index = decode_cpcache_index(which, true);
411 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
412 return e->appendix_if_resolved(cpool);
413 }
416 bool ConstantPool::has_method_type_at_if_loaded(constantPoolHandle cpool, int which) {
417 if (cpool->cache() == NULL) return false; // nothing to load yet
418 int cache_index = decode_cpcache_index(which, true);
419 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
420 return e->has_method_type();
421 }
423 oop ConstantPool::method_type_at_if_loaded(constantPoolHandle cpool, int which) {
424 if (cpool->cache() == NULL) return NULL; // nothing to load yet
425 int cache_index = decode_cpcache_index(which, true);
426 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
427 return e->method_type_if_resolved(cpool);
428 }
431 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
432 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
433 return symbol_at(name_index);
434 }
437 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
438 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
439 return symbol_at(signature_index);
440 }
443 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
444 int i = which;
445 if (!uncached && cache() != NULL) {
446 if (ConstantPool::is_invokedynamic_index(which)) {
447 // Invokedynamic index is index into resolved_references
448 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
449 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
450 assert(tag_at(pool_index).is_name_and_type(), "");
451 return pool_index;
452 }
453 // change byte-ordering and go via cache
454 i = remap_instruction_operand_from_cache(which);
455 } else {
456 if (tag_at(which).is_invoke_dynamic()) {
457 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
458 assert(tag_at(pool_index).is_name_and_type(), "");
459 return pool_index;
460 }
461 }
462 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
463 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
464 jint ref_index = *int_at_addr(i);
465 return extract_high_short_from_int(ref_index);
466 }
469 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
470 guarantee(!ConstantPool::is_invokedynamic_index(which),
471 "an invokedynamic instruction does not have a klass");
472 int i = which;
473 if (!uncached && cache() != NULL) {
474 // change byte-ordering and go via cache
475 i = remap_instruction_operand_from_cache(which);
476 }
477 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
478 jint ref_index = *int_at_addr(i);
479 return extract_low_short_from_int(ref_index);
480 }
484 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
485 int cpc_index = operand;
486 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
487 assert((int)(u2)cpc_index == cpc_index, "clean u2");
488 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
489 return member_index;
490 }
493 void ConstantPool::verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle k, TRAPS) {
494 if (k->oop_is_instance() || k->oop_is_objArray()) {
495 instanceKlassHandle holder (THREAD, this_oop->pool_holder());
496 Klass* elem_oop = k->oop_is_instance() ? k() : ObjArrayKlass::cast(k())->bottom_klass();
497 KlassHandle element (THREAD, elem_oop);
499 // The element type could be a typeArray - we only need the access check if it is
500 // an reference to another class
501 if (element->oop_is_instance()) {
502 LinkResolver::check_klass_accessability(holder, element, CHECK);
503 }
504 }
505 }
508 int ConstantPool::name_ref_index_at(int which_nt) {
509 jint ref_index = name_and_type_at(which_nt);
510 return extract_low_short_from_int(ref_index);
511 }
514 int ConstantPool::signature_ref_index_at(int which_nt) {
515 jint ref_index = name_and_type_at(which_nt);
516 return extract_high_short_from_int(ref_index);
517 }
520 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
521 return klass_at(klass_ref_index_at(which), CHECK_NULL);
522 }
525 Symbol* ConstantPool::klass_name_at(int which) {
526 assert(tag_at(which).is_unresolved_klass() || tag_at(which).is_klass(),
527 "Corrupted constant pool");
528 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
529 // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
530 // tag is not updated atomicly.
531 CPSlot entry = slot_at(which);
532 if (entry.is_resolved()) {
533 // Already resolved - return entry's name.
534 assert(entry.get_klass()->is_klass(), "must be");
535 return entry.get_klass()->name();
536 } else {
537 assert(entry.is_unresolved(), "must be either symbol or klass");
538 return entry.get_symbol();
539 }
540 }
542 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
543 jint ref_index = klass_ref_index_at(which);
544 return klass_at_noresolve(ref_index);
545 }
547 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
548 jint ref_index = uncached_klass_ref_index_at(which);
549 return klass_at_noresolve(ref_index);
550 }
552 char* ConstantPool::string_at_noresolve(int which) {
553 Symbol* s = unresolved_string_at(which);
554 if (s == NULL) {
555 return (char*)"<pseudo-string>";
556 } else {
557 return unresolved_string_at(which)->as_C_string();
558 }
559 }
561 BasicType ConstantPool::basic_type_for_signature_at(int which) {
562 return FieldType::basic_type(symbol_at(which));
563 }
566 void ConstantPool::resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS) {
567 for (int index = 1; index < this_oop->length(); index++) { // Index 0 is unused
568 if (this_oop->tag_at(index).is_string()) {
569 this_oop->string_at(index, CHECK);
570 }
571 }
572 }
574 // Resolve all the classes in the constant pool. If they are all resolved,
575 // the constant pool is read-only. Enhancement: allocate cp entries to
576 // another metaspace, and copy to read-only or read-write space if this
577 // bit is set.
578 bool ConstantPool::resolve_class_constants(TRAPS) {
579 constantPoolHandle cp(THREAD, this);
580 for (int index = 1; index < length(); index++) { // Index 0 is unused
581 if (tag_at(index).is_unresolved_klass() &&
582 klass_at_if_loaded(cp, index) == NULL) {
583 return false;
584 }
585 }
586 // set_preresolution(); or some bit for future use
587 return true;
588 }
590 // If resolution for MethodHandle or MethodType fails, save the exception
591 // in the resolution error table, so that the same exception is thrown again.
592 void ConstantPool::save_and_throw_exception(constantPoolHandle this_oop, int which,
593 int tag, TRAPS) {
594 ResourceMark rm;
595 Symbol* error = PENDING_EXCEPTION->klass()->name();
596 MonitorLockerEx ml(this_oop->lock()); // lock cpool to change tag.
598 int error_tag = (tag == JVM_CONSTANT_MethodHandle) ?
599 JVM_CONSTANT_MethodHandleInError : JVM_CONSTANT_MethodTypeInError;
601 if (!PENDING_EXCEPTION->
602 is_a(SystemDictionary::LinkageError_klass())) {
603 // Just throw the exception and don't prevent these classes from
604 // being loaded due to virtual machine errors like StackOverflow
605 // and OutOfMemoryError, etc, or if the thread was hit by stop()
606 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
608 } else if (this_oop->tag_at(which).value() != error_tag) {
609 SystemDictionary::add_resolution_error(this_oop, which, error);
610 this_oop->tag_at_put(which, error_tag);
611 } else {
612 // some other thread has put the class in error state.
613 error = SystemDictionary::find_resolution_error(this_oop, which);
614 assert(error != NULL, "checking");
615 CLEAR_PENDING_EXCEPTION;
616 THROW_MSG(error, "");
617 }
618 }
621 // Called to resolve constants in the constant pool and return an oop.
622 // Some constant pool entries cache their resolved oop. This is also
623 // called to create oops from constants to use in arguments for invokedynamic
624 oop ConstantPool::resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS) {
625 oop result_oop = NULL;
626 Handle throw_exception;
628 if (cache_index == _possible_index_sentinel) {
629 // It is possible that this constant is one which is cached in the objects.
630 // We'll do a linear search. This should be OK because this usage is rare.
631 assert(index > 0, "valid index");
632 cache_index = this_oop->cp_to_object_index(index);
633 }
634 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
635 assert(index == _no_index_sentinel || index >= 0, "");
637 if (cache_index >= 0) {
638 result_oop = this_oop->resolved_references()->obj_at(cache_index);
639 if (result_oop != NULL) {
640 return result_oop;
641 // That was easy...
642 }
643 index = this_oop->object_to_cp_index(cache_index);
644 }
646 jvalue prim_value; // temp used only in a few cases below
648 int tag_value = this_oop->tag_at(index).value();
650 switch (tag_value) {
652 case JVM_CONSTANT_UnresolvedClass:
653 case JVM_CONSTANT_UnresolvedClassInError:
654 case JVM_CONSTANT_Class:
655 {
656 assert(cache_index == _no_index_sentinel, "should not have been set");
657 Klass* resolved = klass_at_impl(this_oop, index, CHECK_NULL);
658 // ldc wants the java mirror.
659 result_oop = resolved->java_mirror();
660 break;
661 }
663 case JVM_CONSTANT_String:
664 assert(cache_index != _no_index_sentinel, "should have been set");
665 if (this_oop->is_pseudo_string_at(index)) {
666 result_oop = this_oop->pseudo_string_at(index, cache_index);
667 break;
668 }
669 result_oop = string_at_impl(this_oop, index, cache_index, CHECK_NULL);
670 break;
672 case JVM_CONSTANT_MethodHandleInError:
673 case JVM_CONSTANT_MethodTypeInError:
674 {
675 Symbol* error = SystemDictionary::find_resolution_error(this_oop, index);
676 guarantee(error != (Symbol*)NULL, "tag mismatch with resolution error table");
677 ResourceMark rm;
678 THROW_MSG_0(error, "");
679 break;
680 }
682 case JVM_CONSTANT_MethodHandle:
683 {
684 int ref_kind = this_oop->method_handle_ref_kind_at(index);
685 int callee_index = this_oop->method_handle_klass_index_at(index);
686 Symbol* name = this_oop->method_handle_name_ref_at(index);
687 Symbol* signature = this_oop->method_handle_signature_ref_at(index);
688 if (PrintMiscellaneous)
689 tty->print_cr("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
690 ref_kind, index, this_oop->method_handle_index_at(index),
691 callee_index, name->as_C_string(), signature->as_C_string());
692 KlassHandle callee;
693 { Klass* k = klass_at_impl(this_oop, callee_index, CHECK_NULL);
694 callee = KlassHandle(THREAD, k);
695 }
696 KlassHandle klass(THREAD, this_oop->pool_holder());
697 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
698 callee, name, signature,
699 THREAD);
700 result_oop = value();
701 if (HAS_PENDING_EXCEPTION) {
702 save_and_throw_exception(this_oop, index, tag_value, CHECK_NULL);
703 }
704 break;
705 }
707 case JVM_CONSTANT_MethodType:
708 {
709 Symbol* signature = this_oop->method_type_signature_at(index);
710 if (PrintMiscellaneous)
711 tty->print_cr("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
712 index, this_oop->method_type_index_at(index),
713 signature->as_C_string());
714 KlassHandle klass(THREAD, this_oop->pool_holder());
715 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
716 result_oop = value();
717 if (HAS_PENDING_EXCEPTION) {
718 save_and_throw_exception(this_oop, index, tag_value, CHECK_NULL);
719 }
720 break;
721 }
723 case JVM_CONSTANT_Integer:
724 assert(cache_index == _no_index_sentinel, "should not have been set");
725 prim_value.i = this_oop->int_at(index);
726 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
727 break;
729 case JVM_CONSTANT_Float:
730 assert(cache_index == _no_index_sentinel, "should not have been set");
731 prim_value.f = this_oop->float_at(index);
732 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
733 break;
735 case JVM_CONSTANT_Long:
736 assert(cache_index == _no_index_sentinel, "should not have been set");
737 prim_value.j = this_oop->long_at(index);
738 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
739 break;
741 case JVM_CONSTANT_Double:
742 assert(cache_index == _no_index_sentinel, "should not have been set");
743 prim_value.d = this_oop->double_at(index);
744 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
745 break;
747 default:
748 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
749 this_oop(), index, cache_index, tag_value) );
750 assert(false, "unexpected constant tag");
751 break;
752 }
754 if (cache_index >= 0) {
755 // Cache the oop here also.
756 Handle result_handle(THREAD, result_oop);
757 MonitorLockerEx ml(this_oop->lock()); // don't know if we really need this
758 oop result = this_oop->resolved_references()->obj_at(cache_index);
759 // Benign race condition: resolved_references may already be filled in while we were trying to lock.
760 // The important thing here is that all threads pick up the same result.
761 // It doesn't matter which racing thread wins, as long as only one
762 // result is used by all threads, and all future queries.
763 // That result may be either a resolved constant or a failure exception.
764 if (result == NULL) {
765 this_oop->resolved_references()->obj_at_put(cache_index, result_handle());
766 return result_handle();
767 } else {
768 // Return the winning thread's result. This can be different than
769 // result_handle() for MethodHandles.
770 return result;
771 }
772 } else {
773 return result_oop;
774 }
775 }
777 oop ConstantPool::uncached_string_at(int which, TRAPS) {
778 Symbol* sym = unresolved_string_at(which);
779 oop str = StringTable::intern(sym, CHECK_(NULL));
780 assert(java_lang_String::is_instance(str), "must be string");
781 return str;
782 }
785 oop ConstantPool::resolve_bootstrap_specifier_at_impl(constantPoolHandle this_oop, int index, TRAPS) {
786 assert(this_oop->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
788 Handle bsm;
789 int argc;
790 {
791 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
792 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
793 // It is accompanied by the optional arguments.
794 int bsm_index = this_oop->invoke_dynamic_bootstrap_method_ref_index_at(index);
795 oop bsm_oop = this_oop->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
796 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
797 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
798 }
800 // Extract the optional static arguments.
801 argc = this_oop->invoke_dynamic_argument_count_at(index);
802 if (argc == 0) return bsm_oop;
804 bsm = Handle(THREAD, bsm_oop);
805 }
807 objArrayHandle info;
808 {
809 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
810 info = objArrayHandle(THREAD, info_oop);
811 }
813 info->obj_at_put(0, bsm());
814 for (int i = 0; i < argc; i++) {
815 int arg_index = this_oop->invoke_dynamic_argument_index_at(index, i);
816 oop arg_oop = this_oop->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
817 info->obj_at_put(1+i, arg_oop);
818 }
820 return info();
821 }
823 oop ConstantPool::string_at_impl(constantPoolHandle this_oop, int which, int obj_index, TRAPS) {
824 // If the string has already been interned, this entry will be non-null
825 oop str = this_oop->resolved_references()->obj_at(obj_index);
826 if (str != NULL) return str;
827 Symbol* sym = this_oop->unresolved_string_at(which);
828 str = StringTable::intern(sym, CHECK_(NULL));
829 this_oop->string_at_put(which, obj_index, str);
830 assert(java_lang_String::is_instance(str), "must be string");
831 return str;
832 }
835 bool ConstantPool::klass_name_at_matches(instanceKlassHandle k,
836 int which) {
837 // Names are interned, so we can compare Symbol*s directly
838 Symbol* cp_name = klass_name_at(which);
839 return (cp_name == k->name());
840 }
843 // Iterate over symbols and decrement ones which are Symbol*s.
844 // This is done during GC so do not need to lock constantPool unless we
845 // have per-thread safepoints.
846 // Only decrement the UTF8 symbols. Unresolved classes and strings point to
847 // these symbols but didn't increment the reference count.
848 void ConstantPool::unreference_symbols() {
849 for (int index = 1; index < length(); index++) { // Index 0 is unused
850 constantTag tag = tag_at(index);
851 if (tag.is_symbol()) {
852 symbol_at(index)->decrement_refcount();
853 }
854 }
855 }
858 // Compare this constant pool's entry at index1 to the constant pool
859 // cp2's entry at index2.
860 bool ConstantPool::compare_entry_to(int index1, constantPoolHandle cp2,
861 int index2, TRAPS) {
863 // The error tags are equivalent to non-error tags when comparing
864 jbyte t1 = tag_at(index1).non_error_value();
865 jbyte t2 = cp2->tag_at(index2).non_error_value();
867 if (t1 != t2) {
868 // Not the same entry type so there is nothing else to check. Note
869 // that this style of checking will consider resolved/unresolved
870 // class pairs as different.
871 // From the ConstantPool* API point of view, this is correct
872 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
873 // plays out in the context of ConstantPool* merging.
874 return false;
875 }
877 switch (t1) {
878 case JVM_CONSTANT_Class:
879 {
880 Klass* k1 = klass_at(index1, CHECK_false);
881 Klass* k2 = cp2->klass_at(index2, CHECK_false);
882 if (k1 == k2) {
883 return true;
884 }
885 } break;
887 case JVM_CONSTANT_ClassIndex:
888 {
889 int recur1 = klass_index_at(index1);
890 int recur2 = cp2->klass_index_at(index2);
891 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
892 if (match) {
893 return true;
894 }
895 } break;
897 case JVM_CONSTANT_Double:
898 {
899 jdouble d1 = double_at(index1);
900 jdouble d2 = cp2->double_at(index2);
901 if (d1 == d2) {
902 return true;
903 }
904 } break;
906 case JVM_CONSTANT_Fieldref:
907 case JVM_CONSTANT_InterfaceMethodref:
908 case JVM_CONSTANT_Methodref:
909 {
910 int recur1 = uncached_klass_ref_index_at(index1);
911 int recur2 = cp2->uncached_klass_ref_index_at(index2);
912 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
913 if (match) {
914 recur1 = uncached_name_and_type_ref_index_at(index1);
915 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
916 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
917 if (match) {
918 return true;
919 }
920 }
921 } break;
923 case JVM_CONSTANT_Float:
924 {
925 jfloat f1 = float_at(index1);
926 jfloat f2 = cp2->float_at(index2);
927 if (f1 == f2) {
928 return true;
929 }
930 } break;
932 case JVM_CONSTANT_Integer:
933 {
934 jint i1 = int_at(index1);
935 jint i2 = cp2->int_at(index2);
936 if (i1 == i2) {
937 return true;
938 }
939 } break;
941 case JVM_CONSTANT_Long:
942 {
943 jlong l1 = long_at(index1);
944 jlong l2 = cp2->long_at(index2);
945 if (l1 == l2) {
946 return true;
947 }
948 } break;
950 case JVM_CONSTANT_NameAndType:
951 {
952 int recur1 = name_ref_index_at(index1);
953 int recur2 = cp2->name_ref_index_at(index2);
954 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
955 if (match) {
956 recur1 = signature_ref_index_at(index1);
957 recur2 = cp2->signature_ref_index_at(index2);
958 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
959 if (match) {
960 return true;
961 }
962 }
963 } break;
965 case JVM_CONSTANT_StringIndex:
966 {
967 int recur1 = string_index_at(index1);
968 int recur2 = cp2->string_index_at(index2);
969 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
970 if (match) {
971 return true;
972 }
973 } break;
975 case JVM_CONSTANT_UnresolvedClass:
976 {
977 Symbol* k1 = unresolved_klass_at(index1);
978 Symbol* k2 = cp2->unresolved_klass_at(index2);
979 if (k1 == k2) {
980 return true;
981 }
982 } break;
984 case JVM_CONSTANT_MethodType:
985 {
986 int k1 = method_type_index_at_error_ok(index1);
987 int k2 = cp2->method_type_index_at_error_ok(index2);
988 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
989 if (match) {
990 return true;
991 }
992 } break;
994 case JVM_CONSTANT_MethodHandle:
995 {
996 int k1 = method_handle_ref_kind_at_error_ok(index1);
997 int k2 = cp2->method_handle_ref_kind_at_error_ok(index2);
998 if (k1 == k2) {
999 int i1 = method_handle_index_at_error_ok(index1);
1000 int i2 = cp2->method_handle_index_at_error_ok(index2);
1001 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1002 if (match) {
1003 return true;
1004 }
1005 }
1006 } break;
1008 case JVM_CONSTANT_InvokeDynamic:
1009 {
1010 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1011 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1012 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1013 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1014 // separate statements and variables because CHECK_false is used
1015 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1016 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1017 return (match_entry && match_operand);
1018 } break;
1020 case JVM_CONSTANT_String:
1021 {
1022 Symbol* s1 = unresolved_string_at(index1);
1023 Symbol* s2 = cp2->unresolved_string_at(index2);
1024 if (s1 == s2) {
1025 return true;
1026 }
1027 } break;
1029 case JVM_CONSTANT_Utf8:
1030 {
1031 Symbol* s1 = symbol_at(index1);
1032 Symbol* s2 = cp2->symbol_at(index2);
1033 if (s1 == s2) {
1034 return true;
1035 }
1036 } break;
1038 // Invalid is used as the tag for the second constant pool entry
1039 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1040 // not be seen by itself.
1041 case JVM_CONSTANT_Invalid: // fall through
1043 default:
1044 ShouldNotReachHere();
1045 break;
1046 }
1048 return false;
1049 } // end compare_entry_to()
1052 // Resize the operands array with delta_len and delta_size.
1053 // Used in RedefineClasses for CP merge.
1054 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1055 int old_len = operand_array_length(operands());
1056 int new_len = old_len + delta_len;
1057 int min_len = (delta_len > 0) ? old_len : new_len;
1059 int old_size = operands()->length();
1060 int new_size = old_size + delta_size;
1061 int min_size = (delta_size > 0) ? old_size : new_size;
1063 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1064 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1066 // Set index in the resized array for existing elements only
1067 for (int idx = 0; idx < min_len; idx++) {
1068 int offset = operand_offset_at(idx); // offset in original array
1069 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1070 }
1071 // Copy the bootstrap specifiers only
1072 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1073 new_ops->adr_at(2*new_len),
1074 (min_size - 2*min_len) * sizeof(u2));
1075 // Explicitly deallocate old operands array.
1076 // Note, it is not needed for 7u backport.
1077 if ( operands() != NULL) { // the safety check
1078 MetadataFactory::free_array<u2>(loader_data, operands());
1079 }
1080 set_operands(new_ops);
1081 } // end resize_operands()
1084 // Extend the operands array with the length and size of the ext_cp operands.
1085 // Used in RedefineClasses for CP merge.
1086 void ConstantPool::extend_operands(constantPoolHandle ext_cp, TRAPS) {
1087 int delta_len = operand_array_length(ext_cp->operands());
1088 if (delta_len == 0) {
1089 return; // nothing to do
1090 }
1091 int delta_size = ext_cp->operands()->length();
1093 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1095 if (operand_array_length(operands()) == 0) {
1096 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1097 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1098 // The first element index defines the offset of second part
1099 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1100 set_operands(new_ops);
1101 } else {
1102 resize_operands(delta_len, delta_size, CHECK);
1103 }
1105 } // end extend_operands()
1108 // Shrink the operands array to a smaller array with new_len length.
1109 // Used in RedefineClasses for CP merge.
1110 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1111 int old_len = operand_array_length(operands());
1112 if (new_len == old_len) {
1113 return; // nothing to do
1114 }
1115 assert(new_len < old_len, "shrunken operands array must be smaller");
1117 int free_base = operand_next_offset_at(new_len - 1);
1118 int delta_len = new_len - old_len;
1119 int delta_size = 2*delta_len + free_base - operands()->length();
1121 resize_operands(delta_len, delta_size, CHECK);
1123 } // end shrink_operands()
1126 void ConstantPool::copy_operands(constantPoolHandle from_cp,
1127 constantPoolHandle to_cp,
1128 TRAPS) {
1130 int from_oplen = operand_array_length(from_cp->operands());
1131 int old_oplen = operand_array_length(to_cp->operands());
1132 if (from_oplen != 0) {
1133 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1134 // append my operands to the target's operands array
1135 if (old_oplen == 0) {
1136 // Can't just reuse from_cp's operand list because of deallocation issues
1137 int len = from_cp->operands()->length();
1138 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1139 Copy::conjoint_memory_atomic(
1140 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1141 to_cp->set_operands(new_ops);
1142 } else {
1143 int old_len = to_cp->operands()->length();
1144 int from_len = from_cp->operands()->length();
1145 int old_off = old_oplen * sizeof(u2);
1146 int from_off = from_oplen * sizeof(u2);
1147 // Use the metaspace for the destination constant pool
1148 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1149 int fillp = 0, len = 0;
1150 // first part of dest
1151 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1152 new_operands->adr_at(fillp),
1153 (len = old_off) * sizeof(u2));
1154 fillp += len;
1155 // first part of src
1156 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1157 new_operands->adr_at(fillp),
1158 (len = from_off) * sizeof(u2));
1159 fillp += len;
1160 // second part of dest
1161 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1162 new_operands->adr_at(fillp),
1163 (len = old_len - old_off) * sizeof(u2));
1164 fillp += len;
1165 // second part of src
1166 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1167 new_operands->adr_at(fillp),
1168 (len = from_len - from_off) * sizeof(u2));
1169 fillp += len;
1170 assert(fillp == new_operands->length(), "");
1172 // Adjust indexes in the first part of the copied operands array.
1173 for (int j = 0; j < from_oplen; j++) {
1174 int offset = operand_offset_at(new_operands, old_oplen + j);
1175 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1176 offset += old_len; // every new tuple is preceded by old_len extra u2's
1177 operand_offset_at_put(new_operands, old_oplen + j, offset);
1178 }
1180 // replace target operands array with combined array
1181 to_cp->set_operands(new_operands);
1182 }
1183 }
1184 } // end copy_operands()
1187 // Copy this constant pool's entries at start_i to end_i (inclusive)
1188 // to the constant pool to_cp's entries starting at to_i. A total of
1189 // (end_i - start_i) + 1 entries are copied.
1190 void ConstantPool::copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i,
1191 constantPoolHandle to_cp, int to_i, TRAPS) {
1194 int dest_i = to_i; // leave original alone for debug purposes
1196 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1197 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1199 switch (from_cp->tag_at(src_i).value()) {
1200 case JVM_CONSTANT_Double:
1201 case JVM_CONSTANT_Long:
1202 // double and long take two constant pool entries
1203 src_i += 2;
1204 dest_i += 2;
1205 break;
1207 default:
1208 // all others take one constant pool entry
1209 src_i++;
1210 dest_i++;
1211 break;
1212 }
1213 }
1214 copy_operands(from_cp, to_cp, CHECK);
1216 } // end copy_cp_to_impl()
1219 // Copy this constant pool's entry at from_i to the constant pool
1220 // to_cp's entry at to_i.
1221 void ConstantPool::copy_entry_to(constantPoolHandle from_cp, int from_i,
1222 constantPoolHandle to_cp, int to_i,
1223 TRAPS) {
1225 int tag = from_cp->tag_at(from_i).value();
1226 switch (tag) {
1227 case JVM_CONSTANT_Class:
1228 {
1229 Klass* k = from_cp->klass_at(from_i, CHECK);
1230 to_cp->klass_at_put(to_i, k);
1231 } break;
1233 case JVM_CONSTANT_ClassIndex:
1234 {
1235 jint ki = from_cp->klass_index_at(from_i);
1236 to_cp->klass_index_at_put(to_i, ki);
1237 } break;
1239 case JVM_CONSTANT_Double:
1240 {
1241 jdouble d = from_cp->double_at(from_i);
1242 to_cp->double_at_put(to_i, d);
1243 // double takes two constant pool entries so init second entry's tag
1244 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1245 } break;
1247 case JVM_CONSTANT_Fieldref:
1248 {
1249 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1250 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1251 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1252 } break;
1254 case JVM_CONSTANT_Float:
1255 {
1256 jfloat f = from_cp->float_at(from_i);
1257 to_cp->float_at_put(to_i, f);
1258 } break;
1260 case JVM_CONSTANT_Integer:
1261 {
1262 jint i = from_cp->int_at(from_i);
1263 to_cp->int_at_put(to_i, i);
1264 } break;
1266 case JVM_CONSTANT_InterfaceMethodref:
1267 {
1268 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1269 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1270 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1271 } break;
1273 case JVM_CONSTANT_Long:
1274 {
1275 jlong l = from_cp->long_at(from_i);
1276 to_cp->long_at_put(to_i, l);
1277 // long takes two constant pool entries so init second entry's tag
1278 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1279 } break;
1281 case JVM_CONSTANT_Methodref:
1282 {
1283 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1284 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1285 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1286 } break;
1288 case JVM_CONSTANT_NameAndType:
1289 {
1290 int name_ref_index = from_cp->name_ref_index_at(from_i);
1291 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1292 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1293 } break;
1295 case JVM_CONSTANT_StringIndex:
1296 {
1297 jint si = from_cp->string_index_at(from_i);
1298 to_cp->string_index_at_put(to_i, si);
1299 } break;
1301 case JVM_CONSTANT_UnresolvedClass:
1302 case JVM_CONSTANT_UnresolvedClassInError:
1303 {
1304 // Can be resolved after checking tag, so check the slot first.
1305 CPSlot entry = from_cp->slot_at(from_i);
1306 if (entry.is_resolved()) {
1307 assert(entry.get_klass()->is_klass(), "must be");
1308 // Already resolved
1309 to_cp->klass_at_put(to_i, entry.get_klass());
1310 } else {
1311 to_cp->unresolved_klass_at_put(to_i, entry.get_symbol());
1312 }
1313 } break;
1315 case JVM_CONSTANT_String:
1316 {
1317 Symbol* s = from_cp->unresolved_string_at(from_i);
1318 to_cp->unresolved_string_at_put(to_i, s);
1319 } break;
1321 case JVM_CONSTANT_Utf8:
1322 {
1323 Symbol* s = from_cp->symbol_at(from_i);
1324 // Need to increase refcount, the old one will be thrown away and deferenced
1325 s->increment_refcount();
1326 to_cp->symbol_at_put(to_i, s);
1327 } break;
1329 case JVM_CONSTANT_MethodType:
1330 case JVM_CONSTANT_MethodTypeInError:
1331 {
1332 jint k = from_cp->method_type_index_at_error_ok(from_i);
1333 to_cp->method_type_index_at_put(to_i, k);
1334 } break;
1336 case JVM_CONSTANT_MethodHandle:
1337 case JVM_CONSTANT_MethodHandleInError:
1338 {
1339 int k1 = from_cp->method_handle_ref_kind_at_error_ok(from_i);
1340 int k2 = from_cp->method_handle_index_at_error_ok(from_i);
1341 to_cp->method_handle_index_at_put(to_i, k1, k2);
1342 } break;
1344 case JVM_CONSTANT_InvokeDynamic:
1345 {
1346 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1347 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1348 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1349 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1350 } break;
1352 // Invalid is used as the tag for the second constant pool entry
1353 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1354 // not be seen by itself.
1355 case JVM_CONSTANT_Invalid: // fall through
1357 default:
1358 {
1359 ShouldNotReachHere();
1360 } break;
1361 }
1362 } // end copy_entry_to()
1365 // Search constant pool search_cp for an entry that matches this
1366 // constant pool's entry at pattern_i. Returns the index of a
1367 // matching entry or zero (0) if there is no matching entry.
1368 int ConstantPool::find_matching_entry(int pattern_i,
1369 constantPoolHandle search_cp, TRAPS) {
1371 // index zero (0) is not used
1372 for (int i = 1; i < search_cp->length(); i++) {
1373 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1374 if (found) {
1375 return i;
1376 }
1377 }
1379 return 0; // entry not found; return unused index zero (0)
1380 } // end find_matching_entry()
1383 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1384 // cp2's bootstrap specifier at idx2.
1385 bool ConstantPool::compare_operand_to(int idx1, constantPoolHandle cp2, int idx2, TRAPS) {
1386 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1387 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1388 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1390 if (!match) {
1391 return false;
1392 }
1393 int argc = operand_argument_count_at(idx1);
1394 if (argc == cp2->operand_argument_count_at(idx2)) {
1395 for (int j = 0; j < argc; j++) {
1396 k1 = operand_argument_index_at(idx1, j);
1397 k2 = cp2->operand_argument_index_at(idx2, j);
1398 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1399 if (!match) {
1400 return false;
1401 }
1402 }
1403 return true; // got through loop; all elements equal
1404 }
1405 return false;
1406 } // end compare_operand_to()
1408 // Search constant pool search_cp for a bootstrap specifier that matches
1409 // this constant pool's bootstrap specifier at pattern_i index.
1410 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1411 int ConstantPool::find_matching_operand(int pattern_i,
1412 constantPoolHandle search_cp, int search_len, TRAPS) {
1413 for (int i = 0; i < search_len; i++) {
1414 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1415 if (found) {
1416 return i;
1417 }
1418 }
1419 return -1; // bootstrap specifier not found; return unused index (-1)
1420 } // end find_matching_operand()
1423 #ifndef PRODUCT
1425 const char* ConstantPool::printable_name_at(int which) {
1427 constantTag tag = tag_at(which);
1429 if (tag.is_string()) {
1430 return string_at_noresolve(which);
1431 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1432 return klass_name_at(which)->as_C_string();
1433 } else if (tag.is_symbol()) {
1434 return symbol_at(which)->as_C_string();
1435 }
1436 return "";
1437 }
1439 #endif // PRODUCT
1442 // JVMTI GetConstantPool support
1444 // For debugging of constant pool
1445 const bool debug_cpool = false;
1447 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1449 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1450 const char* WARN_MSG = "Must not be such entry!";
1451 jint size = 0;
1452 u2 idx1, idx2;
1454 for (jint idx = 1; idx < cnt; idx++) {
1455 jint ent_size = 0;
1456 u1 tag = *bytes++;
1457 size++; // count tag
1459 printf("const #%03d, tag: %02d ", idx, tag);
1460 switch(tag) {
1461 case JVM_CONSTANT_Invalid: {
1462 printf("Invalid");
1463 break;
1464 }
1465 case JVM_CONSTANT_Unicode: {
1466 printf("Unicode %s", WARN_MSG);
1467 break;
1468 }
1469 case JVM_CONSTANT_Utf8: {
1470 u2 len = Bytes::get_Java_u2(bytes);
1471 char str[128];
1472 if (len > 127) {
1473 len = 127;
1474 }
1475 strncpy(str, (char *) (bytes+2), len);
1476 str[len] = '\0';
1477 printf("Utf8 \"%s\"", str);
1478 ent_size = 2 + len;
1479 break;
1480 }
1481 case JVM_CONSTANT_Integer: {
1482 u4 val = Bytes::get_Java_u4(bytes);
1483 printf("int %d", *(int *) &val);
1484 ent_size = 4;
1485 break;
1486 }
1487 case JVM_CONSTANT_Float: {
1488 u4 val = Bytes::get_Java_u4(bytes);
1489 printf("float %5.3ff", *(float *) &val);
1490 ent_size = 4;
1491 break;
1492 }
1493 case JVM_CONSTANT_Long: {
1494 u8 val = Bytes::get_Java_u8(bytes);
1495 printf("long "INT64_FORMAT, (int64_t) *(jlong *) &val);
1496 ent_size = 8;
1497 idx++; // Long takes two cpool slots
1498 break;
1499 }
1500 case JVM_CONSTANT_Double: {
1501 u8 val = Bytes::get_Java_u8(bytes);
1502 printf("double %5.3fd", *(jdouble *)&val);
1503 ent_size = 8;
1504 idx++; // Double takes two cpool slots
1505 break;
1506 }
1507 case JVM_CONSTANT_Class: {
1508 idx1 = Bytes::get_Java_u2(bytes);
1509 printf("class #%03d", idx1);
1510 ent_size = 2;
1511 break;
1512 }
1513 case JVM_CONSTANT_String: {
1514 idx1 = Bytes::get_Java_u2(bytes);
1515 printf("String #%03d", idx1);
1516 ent_size = 2;
1517 break;
1518 }
1519 case JVM_CONSTANT_Fieldref: {
1520 idx1 = Bytes::get_Java_u2(bytes);
1521 idx2 = Bytes::get_Java_u2(bytes+2);
1522 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1523 ent_size = 4;
1524 break;
1525 }
1526 case JVM_CONSTANT_Methodref: {
1527 idx1 = Bytes::get_Java_u2(bytes);
1528 idx2 = Bytes::get_Java_u2(bytes+2);
1529 printf("Method #%03d, #%03d", idx1, idx2);
1530 ent_size = 4;
1531 break;
1532 }
1533 case JVM_CONSTANT_InterfaceMethodref: {
1534 idx1 = Bytes::get_Java_u2(bytes);
1535 idx2 = Bytes::get_Java_u2(bytes+2);
1536 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1537 ent_size = 4;
1538 break;
1539 }
1540 case JVM_CONSTANT_NameAndType: {
1541 idx1 = Bytes::get_Java_u2(bytes);
1542 idx2 = Bytes::get_Java_u2(bytes+2);
1543 printf("NameAndType #%03d, #%03d", idx1, idx2);
1544 ent_size = 4;
1545 break;
1546 }
1547 case JVM_CONSTANT_ClassIndex: {
1548 printf("ClassIndex %s", WARN_MSG);
1549 break;
1550 }
1551 case JVM_CONSTANT_UnresolvedClass: {
1552 printf("UnresolvedClass: %s", WARN_MSG);
1553 break;
1554 }
1555 case JVM_CONSTANT_UnresolvedClassInError: {
1556 printf("UnresolvedClassInErr: %s", WARN_MSG);
1557 break;
1558 }
1559 case JVM_CONSTANT_StringIndex: {
1560 printf("StringIndex: %s", WARN_MSG);
1561 break;
1562 }
1563 }
1564 printf(";\n");
1565 bytes += ent_size;
1566 size += ent_size;
1567 }
1568 printf("Cpool size: %d\n", size);
1569 fflush(0);
1570 return;
1571 } /* end print_cpool_bytes */
1574 // Returns size of constant pool entry.
1575 jint ConstantPool::cpool_entry_size(jint idx) {
1576 switch(tag_at(idx).value()) {
1577 case JVM_CONSTANT_Invalid:
1578 case JVM_CONSTANT_Unicode:
1579 return 1;
1581 case JVM_CONSTANT_Utf8:
1582 return 3 + symbol_at(idx)->utf8_length();
1584 case JVM_CONSTANT_Class:
1585 case JVM_CONSTANT_String:
1586 case JVM_CONSTANT_ClassIndex:
1587 case JVM_CONSTANT_UnresolvedClass:
1588 case JVM_CONSTANT_UnresolvedClassInError:
1589 case JVM_CONSTANT_StringIndex:
1590 case JVM_CONSTANT_MethodType:
1591 case JVM_CONSTANT_MethodTypeInError:
1592 return 3;
1594 case JVM_CONSTANT_MethodHandle:
1595 case JVM_CONSTANT_MethodHandleInError:
1596 return 4; //tag, ref_kind, ref_index
1598 case JVM_CONSTANT_Integer:
1599 case JVM_CONSTANT_Float:
1600 case JVM_CONSTANT_Fieldref:
1601 case JVM_CONSTANT_Methodref:
1602 case JVM_CONSTANT_InterfaceMethodref:
1603 case JVM_CONSTANT_NameAndType:
1604 return 5;
1606 case JVM_CONSTANT_InvokeDynamic:
1607 // u1 tag, u2 bsm, u2 nt
1608 return 5;
1610 case JVM_CONSTANT_Long:
1611 case JVM_CONSTANT_Double:
1612 return 9;
1613 }
1614 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1615 return 1;
1616 } /* end cpool_entry_size */
1619 // SymbolHashMap is used to find a constant pool index from a string.
1620 // This function fills in SymbolHashMaps, one for utf8s and one for
1621 // class names, returns size of the cpool raw bytes.
1622 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1623 SymbolHashMap *classmap) {
1624 jint size = 0;
1626 for (u2 idx = 1; idx < length(); idx++) {
1627 u2 tag = tag_at(idx).value();
1628 size += cpool_entry_size(idx);
1630 switch(tag) {
1631 case JVM_CONSTANT_Utf8: {
1632 Symbol* sym = symbol_at(idx);
1633 symmap->add_entry(sym, idx);
1634 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1635 break;
1636 }
1637 case JVM_CONSTANT_Class:
1638 case JVM_CONSTANT_UnresolvedClass:
1639 case JVM_CONSTANT_UnresolvedClassInError: {
1640 Symbol* sym = klass_name_at(idx);
1641 classmap->add_entry(sym, idx);
1642 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1643 break;
1644 }
1645 case JVM_CONSTANT_Long:
1646 case JVM_CONSTANT_Double: {
1647 idx++; // Both Long and Double take two cpool slots
1648 break;
1649 }
1650 }
1651 }
1652 return size;
1653 } /* end hash_utf8_entries_to */
1656 // Copy cpool bytes.
1657 // Returns:
1658 // 0, in case of OutOfMemoryError
1659 // -1, in case of internal error
1660 // > 0, count of the raw cpool bytes that have been copied
1661 int ConstantPool::copy_cpool_bytes(int cpool_size,
1662 SymbolHashMap* tbl,
1663 unsigned char *bytes) {
1664 u2 idx1, idx2;
1665 jint size = 0;
1666 jint cnt = length();
1667 unsigned char *start_bytes = bytes;
1669 for (jint idx = 1; idx < cnt; idx++) {
1670 u1 tag = tag_at(idx).value();
1671 jint ent_size = cpool_entry_size(idx);
1673 assert(size + ent_size <= cpool_size, "Size mismatch");
1675 *bytes = tag;
1676 DBG(printf("#%03hd tag=%03hd, ", idx, tag));
1677 switch(tag) {
1678 case JVM_CONSTANT_Invalid: {
1679 DBG(printf("JVM_CONSTANT_Invalid"));
1680 break;
1681 }
1682 case JVM_CONSTANT_Unicode: {
1683 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1684 DBG(printf("JVM_CONSTANT_Unicode"));
1685 break;
1686 }
1687 case JVM_CONSTANT_Utf8: {
1688 Symbol* sym = symbol_at(idx);
1689 char* str = sym->as_utf8();
1690 // Warning! It's crashing on x86 with len = sym->utf8_length()
1691 int len = (int) strlen(str);
1692 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1693 for (int i = 0; i < len; i++) {
1694 bytes[3+i] = (u1) str[i];
1695 }
1696 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1697 break;
1698 }
1699 case JVM_CONSTANT_Integer: {
1700 jint val = int_at(idx);
1701 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1702 break;
1703 }
1704 case JVM_CONSTANT_Float: {
1705 jfloat val = float_at(idx);
1706 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1707 break;
1708 }
1709 case JVM_CONSTANT_Long: {
1710 jlong val = long_at(idx);
1711 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1712 idx++; // Long takes two cpool slots
1713 break;
1714 }
1715 case JVM_CONSTANT_Double: {
1716 jdouble val = double_at(idx);
1717 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1718 idx++; // Double takes two cpool slots
1719 break;
1720 }
1721 case JVM_CONSTANT_Class:
1722 case JVM_CONSTANT_UnresolvedClass:
1723 case JVM_CONSTANT_UnresolvedClassInError: {
1724 *bytes = JVM_CONSTANT_Class;
1725 Symbol* sym = klass_name_at(idx);
1726 idx1 = tbl->symbol_to_value(sym);
1727 assert(idx1 != 0, "Have not found a hashtable entry");
1728 Bytes::put_Java_u2((address) (bytes+1), idx1);
1729 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1730 break;
1731 }
1732 case JVM_CONSTANT_String: {
1733 *bytes = JVM_CONSTANT_String;
1734 Symbol* sym = unresolved_string_at(idx);
1735 idx1 = tbl->symbol_to_value(sym);
1736 assert(idx1 != 0, "Have not found a hashtable entry");
1737 Bytes::put_Java_u2((address) (bytes+1), idx1);
1738 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1739 break;
1740 }
1741 case JVM_CONSTANT_Fieldref:
1742 case JVM_CONSTANT_Methodref:
1743 case JVM_CONSTANT_InterfaceMethodref: {
1744 idx1 = uncached_klass_ref_index_at(idx);
1745 idx2 = uncached_name_and_type_ref_index_at(idx);
1746 Bytes::put_Java_u2((address) (bytes+1), idx1);
1747 Bytes::put_Java_u2((address) (bytes+3), idx2);
1748 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1749 break;
1750 }
1751 case JVM_CONSTANT_NameAndType: {
1752 idx1 = name_ref_index_at(idx);
1753 idx2 = signature_ref_index_at(idx);
1754 Bytes::put_Java_u2((address) (bytes+1), idx1);
1755 Bytes::put_Java_u2((address) (bytes+3), idx2);
1756 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1757 break;
1758 }
1759 case JVM_CONSTANT_ClassIndex: {
1760 *bytes = JVM_CONSTANT_Class;
1761 idx1 = klass_index_at(idx);
1762 Bytes::put_Java_u2((address) (bytes+1), idx1);
1763 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1764 break;
1765 }
1766 case JVM_CONSTANT_StringIndex: {
1767 *bytes = JVM_CONSTANT_String;
1768 idx1 = string_index_at(idx);
1769 Bytes::put_Java_u2((address) (bytes+1), idx1);
1770 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1771 break;
1772 }
1773 case JVM_CONSTANT_MethodHandle:
1774 case JVM_CONSTANT_MethodHandleInError: {
1775 *bytes = JVM_CONSTANT_MethodHandle;
1776 int kind = method_handle_ref_kind_at_error_ok(idx);
1777 idx1 = method_handle_index_at_error_ok(idx);
1778 *(bytes+1) = (unsigned char) kind;
1779 Bytes::put_Java_u2((address) (bytes+2), idx1);
1780 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1781 break;
1782 }
1783 case JVM_CONSTANT_MethodType:
1784 case JVM_CONSTANT_MethodTypeInError: {
1785 *bytes = JVM_CONSTANT_MethodType;
1786 idx1 = method_type_index_at_error_ok(idx);
1787 Bytes::put_Java_u2((address) (bytes+1), idx1);
1788 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1789 break;
1790 }
1791 case JVM_CONSTANT_InvokeDynamic: {
1792 *bytes = tag;
1793 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1794 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1795 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1796 Bytes::put_Java_u2((address) (bytes+1), idx1);
1797 Bytes::put_Java_u2((address) (bytes+3), idx2);
1798 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1799 break;
1800 }
1801 }
1802 DBG(printf("\n"));
1803 bytes += ent_size;
1804 size += ent_size;
1805 }
1806 assert(size == cpool_size, "Size mismatch");
1808 // Keep temorarily for debugging until it's stable.
1809 DBG(print_cpool_bytes(cnt, start_bytes));
1810 return (int)(bytes - start_bytes);
1811 } /* end copy_cpool_bytes */
1813 #undef DBG
1816 void ConstantPool::set_on_stack(const bool value) {
1817 if (value) {
1818 _flags |= _on_stack;
1819 } else {
1820 _flags &= ~_on_stack;
1821 }
1822 if (value) MetadataOnStackMark::record(this);
1823 }
1825 // JSR 292 support for patching constant pool oops after the class is linked and
1826 // the oop array for resolved references are created.
1827 // We can't do this during classfile parsing, which is how the other indexes are
1828 // patched. The other patches are applied early for some error checking
1829 // so only defer the pseudo_strings.
1830 void ConstantPool::patch_resolved_references(
1831 GrowableArray<Handle>* cp_patches) {
1832 assert(EnableInvokeDynamic, "");
1833 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
1834 Handle patch = cp_patches->at(index);
1835 if (patch.not_null()) {
1836 assert (tag_at(index).is_string(), "should only be string left");
1837 // Patching a string means pre-resolving it.
1838 // The spelling in the constant pool is ignored.
1839 // The constant reference may be any object whatever.
1840 // If it is not a real interned string, the constant is referred
1841 // to as a "pseudo-string", and must be presented to the CP
1842 // explicitly, because it may require scavenging.
1843 int obj_index = cp_to_object_index(index);
1844 pseudo_string_at_put(index, obj_index, patch());
1845 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
1846 }
1847 }
1848 #ifdef ASSERT
1849 // Ensure that all the patches have been used.
1850 for (int index = 0; index < cp_patches->length(); index++) {
1851 assert(cp_patches->at(index).is_null(),
1852 err_msg("Unused constant pool patch at %d in class file %s",
1853 index,
1854 pool_holder()->external_name()));
1855 }
1856 #endif // ASSERT
1857 }
1859 #ifndef PRODUCT
1861 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
1862 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
1863 guarantee(obj->is_constantPool(), "object must be constant pool");
1864 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
1865 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
1867 for (int i = 0; i< cp->length(); i++) {
1868 if (cp->tag_at(i).is_unresolved_klass()) {
1869 // This will force loading of the class
1870 Klass* klass = cp->klass_at(i, CHECK);
1871 if (klass->oop_is_instance()) {
1872 // Force initialization of class
1873 InstanceKlass::cast(klass)->initialize(CHECK);
1874 }
1875 }
1876 }
1877 }
1879 #endif
1882 // Printing
1884 void ConstantPool::print_on(outputStream* st) const {
1885 EXCEPTION_MARK;
1886 assert(is_constantPool(), "must be constantPool");
1887 st->print_cr(internal_name());
1888 if (flags() != 0) {
1889 st->print(" - flags: 0x%x", flags());
1890 if (has_preresolution()) st->print(" has_preresolution");
1891 if (on_stack()) st->print(" on_stack");
1892 st->cr();
1893 }
1894 if (pool_holder() != NULL) {
1895 st->print_cr(" - holder: " INTPTR_FORMAT, pool_holder());
1896 }
1897 st->print_cr(" - cache: " INTPTR_FORMAT, cache());
1898 st->print_cr(" - resolved_references: " INTPTR_FORMAT, (void *)resolved_references());
1899 st->print_cr(" - reference_map: " INTPTR_FORMAT, reference_map());
1901 for (int index = 1; index < length(); index++) { // Index 0 is unused
1902 ((ConstantPool*)this)->print_entry_on(index, st);
1903 switch (tag_at(index).value()) {
1904 case JVM_CONSTANT_Long :
1905 case JVM_CONSTANT_Double :
1906 index++; // Skip entry following eigth-byte constant
1907 }
1909 }
1910 st->cr();
1911 }
1913 // Print one constant pool entry
1914 void ConstantPool::print_entry_on(const int index, outputStream* st) {
1915 EXCEPTION_MARK;
1916 st->print(" - %3d : ", index);
1917 tag_at(index).print_on(st);
1918 st->print(" : ");
1919 switch (tag_at(index).value()) {
1920 case JVM_CONSTANT_Class :
1921 { Klass* k = klass_at(index, CATCH);
1922 guarantee(k != NULL, "need klass");
1923 k->print_value_on(st);
1924 st->print(" {0x%lx}", (address)k);
1925 }
1926 break;
1927 case JVM_CONSTANT_Fieldref :
1928 case JVM_CONSTANT_Methodref :
1929 case JVM_CONSTANT_InterfaceMethodref :
1930 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
1931 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
1932 break;
1933 case JVM_CONSTANT_String :
1934 if (is_pseudo_string_at(index)) {
1935 oop anObj = pseudo_string_at(index);
1936 anObj->print_value_on(st);
1937 st->print(" {0x%lx}", (address)anObj);
1938 } else {
1939 unresolved_string_at(index)->print_value_on(st);
1940 }
1941 break;
1942 case JVM_CONSTANT_Integer :
1943 st->print("%d", int_at(index));
1944 break;
1945 case JVM_CONSTANT_Float :
1946 st->print("%f", float_at(index));
1947 break;
1948 case JVM_CONSTANT_Long :
1949 st->print_jlong(long_at(index));
1950 break;
1951 case JVM_CONSTANT_Double :
1952 st->print("%lf", double_at(index));
1953 break;
1954 case JVM_CONSTANT_NameAndType :
1955 st->print("name_index=%d", name_ref_index_at(index));
1956 st->print(" signature_index=%d", signature_ref_index_at(index));
1957 break;
1958 case JVM_CONSTANT_Utf8 :
1959 symbol_at(index)->print_value_on(st);
1960 break;
1961 case JVM_CONSTANT_UnresolvedClass : // fall-through
1962 case JVM_CONSTANT_UnresolvedClassInError: {
1963 // unresolved_klass_at requires lock or safe world.
1964 CPSlot entry = slot_at(index);
1965 if (entry.is_resolved()) {
1966 entry.get_klass()->print_value_on(st);
1967 } else {
1968 entry.get_symbol()->print_value_on(st);
1969 }
1970 }
1971 break;
1972 case JVM_CONSTANT_MethodHandle :
1973 case JVM_CONSTANT_MethodHandleInError :
1974 st->print("ref_kind=%d", method_handle_ref_kind_at_error_ok(index));
1975 st->print(" ref_index=%d", method_handle_index_at_error_ok(index));
1976 break;
1977 case JVM_CONSTANT_MethodType :
1978 case JVM_CONSTANT_MethodTypeInError :
1979 st->print("signature_index=%d", method_type_index_at_error_ok(index));
1980 break;
1981 case JVM_CONSTANT_InvokeDynamic :
1982 {
1983 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
1984 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
1985 int argc = invoke_dynamic_argument_count_at(index);
1986 if (argc > 0) {
1987 for (int arg_i = 0; arg_i < argc; arg_i++) {
1988 int arg = invoke_dynamic_argument_index_at(index, arg_i);
1989 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
1990 }
1991 st->print("}");
1992 }
1993 }
1994 break;
1995 default:
1996 ShouldNotReachHere();
1997 break;
1998 }
1999 st->cr();
2000 }
2002 void ConstantPool::print_value_on(outputStream* st) const {
2003 assert(is_constantPool(), "must be constantPool");
2004 st->print("constant pool [%d]", length());
2005 if (has_preresolution()) st->print("/preresolution");
2006 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2007 print_address_on(st);
2008 st->print(" for ");
2009 pool_holder()->print_value_on(st);
2010 if (pool_holder() != NULL) {
2011 bool extra = (pool_holder()->constants() != this);
2012 if (extra) st->print(" (extra)");
2013 }
2014 if (cache() != NULL) {
2015 st->print(" cache=" PTR_FORMAT, cache());
2016 }
2017 }
2019 #if INCLUDE_SERVICES
2020 // Size Statistics
2021 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2022 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2023 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2024 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2025 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2026 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2028 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2029 sz->_cp_refmap_bytes;
2030 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2031 }
2032 #endif // INCLUDE_SERVICES
2034 // Verification
2036 void ConstantPool::verify_on(outputStream* st) {
2037 guarantee(is_constantPool(), "object must be constant pool");
2038 for (int i = 0; i< length(); i++) {
2039 constantTag tag = tag_at(i);
2040 CPSlot entry = slot_at(i);
2041 if (tag.is_klass()) {
2042 if (entry.is_resolved()) {
2043 guarantee(entry.get_klass()->is_klass(), "should be klass");
2044 }
2045 } else if (tag.is_unresolved_klass()) {
2046 if (entry.is_resolved()) {
2047 guarantee(entry.get_klass()->is_klass(), "should be klass");
2048 }
2049 } else if (tag.is_symbol()) {
2050 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2051 } else if (tag.is_string()) {
2052 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2053 }
2054 }
2055 if (cache() != NULL) {
2056 // Note: cache() can be NULL before a class is completely setup or
2057 // in temporary constant pools used during constant pool merging
2058 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2059 }
2060 if (pool_holder() != NULL) {
2061 // Note: pool_holder() can be NULL in temporary constant pools
2062 // used during constant pool merging
2063 guarantee(pool_holder()->is_klass(), "should be klass");
2064 }
2065 }
2068 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2069 char *str = sym->as_utf8();
2070 unsigned int hash = compute_hash(str, sym->utf8_length());
2071 unsigned int index = hash % table_size();
2073 // check if already in map
2074 // we prefer the first entry since it is more likely to be what was used in
2075 // the class file
2076 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2077 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2078 if (en->hash() == hash && en->symbol() == sym) {
2079 return; // already there
2080 }
2081 }
2083 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2084 entry->set_next(bucket(index));
2085 _buckets[index].set_entry(entry);
2086 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2087 }
2089 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2090 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2091 char *str = sym->as_utf8();
2092 int len = sym->utf8_length();
2093 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2094 unsigned int index = hash % table_size();
2095 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2096 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2097 if (en->hash() == hash && en->symbol() == sym) {
2098 return en;
2099 }
2100 }
2101 return NULL;
2102 }