Mon, 05 May 2014 19:53:00 -0400
8023697: failed class resolution reports different class name in detail message for the first and subsequent times
Summary: Cache detail message when we cache exception for constant pool resolution.
Reviewed-by: acorn, twisti, jrose
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 // class of the original error and throw another error of the same class (JVMS 5.4.3).
239 // If there is a detail message, pass that detail message to the error constructor.
240 // The JVMS does not strictly require us to duplicate the same detail message,
241 // or any internal exception fields such as cause or stacktrace. But since the
242 // detail message is often a class name or other literal string, we will repeat it if
243 // we can find it in the symbol table.
244 if (in_error) {
245 throw_resolution_error(this_oop, which, CHECK_0);
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 MonitorLockerEx ml(this_oop->lock());
267 // some other thread has beaten us and has resolved the class.
268 if (this_oop->tag_at(which).is_klass()) {
269 CLEAR_PENDING_EXCEPTION;
270 entry = this_oop->resolved_klass_at(which);
271 return entry.get_klass();
272 }
274 // The tag could have changed to in-error before the lock but we have to
275 // handle that here for the class case.
276 save_and_throw_exception(this_oop, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_0);
277 }
279 if (TraceClassResolution && !k()->oop_is_array()) {
280 // skip resolving the constant pool so that this code get's
281 // called the next time some bytecodes refer to this class.
282 ResourceMark rm;
283 int line_number = -1;
284 const char * source_file = NULL;
285 if (JavaThread::current()->has_last_Java_frame()) {
286 // try to identify the method which called this function.
287 vframeStream vfst(JavaThread::current());
288 if (!vfst.at_end()) {
289 line_number = vfst.method()->line_number_from_bci(vfst.bci());
290 Symbol* s = vfst.method()->method_holder()->source_file_name();
291 if (s != NULL) {
292 source_file = s->as_C_string();
293 }
294 }
295 }
296 if (k() != this_oop->pool_holder()) {
297 // only print something if the classes are different
298 if (source_file != NULL) {
299 tty->print("RESOLVE %s %s %s:%d\n",
300 this_oop->pool_holder()->external_name(),
301 InstanceKlass::cast(k())->external_name(), source_file, line_number);
302 } else {
303 tty->print("RESOLVE %s %s\n",
304 this_oop->pool_holder()->external_name(),
305 InstanceKlass::cast(k())->external_name());
306 }
307 }
308 return k();
309 } else {
310 MonitorLockerEx ml(this_oop->lock());
311 // Only updated constant pool - if it is resolved.
312 do_resolve = this_oop->tag_at(which).is_unresolved_klass();
313 if (do_resolve) {
314 this_oop->klass_at_put(which, k());
315 }
316 }
317 }
319 entry = this_oop->resolved_klass_at(which);
320 assert(entry.is_resolved() && entry.get_klass()->is_klass(), "must be resolved at this point");
321 return entry.get_klass();
322 }
325 // Does not update ConstantPool* - to avoid any exception throwing. Used
326 // by compiler and exception handling. Also used to avoid classloads for
327 // instanceof operations. Returns NULL if the class has not been loaded or
328 // if the verification of constant pool failed
329 Klass* ConstantPool::klass_at_if_loaded(constantPoolHandle this_oop, int which) {
330 CPSlot entry = this_oop->slot_at(which);
331 if (entry.is_resolved()) {
332 assert(entry.get_klass()->is_klass(), "must be");
333 return entry.get_klass();
334 } else {
335 assert(entry.is_unresolved(), "must be either symbol or klass");
336 Thread *thread = Thread::current();
337 Symbol* name = entry.get_symbol();
338 oop loader = this_oop->pool_holder()->class_loader();
339 oop protection_domain = this_oop->pool_holder()->protection_domain();
340 Handle h_prot (thread, protection_domain);
341 Handle h_loader (thread, loader);
342 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
344 if (k != NULL) {
345 // Make sure that resolving is legal
346 EXCEPTION_MARK;
347 KlassHandle klass(THREAD, k);
348 // return NULL if verification fails
349 verify_constant_pool_resolve(this_oop, klass, THREAD);
350 if (HAS_PENDING_EXCEPTION) {
351 CLEAR_PENDING_EXCEPTION;
352 return NULL;
353 }
354 return klass();
355 } else {
356 return k;
357 }
358 }
359 }
362 Klass* ConstantPool::klass_ref_at_if_loaded(constantPoolHandle this_oop, int which) {
363 return klass_at_if_loaded(this_oop, this_oop->klass_ref_index_at(which));
364 }
367 Method* ConstantPool::method_at_if_loaded(constantPoolHandle cpool,
368 int which) {
369 if (cpool->cache() == NULL) return NULL; // nothing to load yet
370 int cache_index = decode_cpcache_index(which, true);
371 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
372 // FIXME: should be an assert
373 if (PrintMiscellaneous && (Verbose||WizardMode)) {
374 tty->print_cr("bad operand %d in:", which); cpool->print();
375 }
376 return NULL;
377 }
378 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
379 return e->method_if_resolved(cpool);
380 }
383 bool ConstantPool::has_appendix_at_if_loaded(constantPoolHandle cpool, int which) {
384 if (cpool->cache() == NULL) return false; // nothing to load yet
385 int cache_index = decode_cpcache_index(which, true);
386 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
387 return e->has_appendix();
388 }
390 oop ConstantPool::appendix_at_if_loaded(constantPoolHandle cpool, int which) {
391 if (cpool->cache() == NULL) return NULL; // nothing to load yet
392 int cache_index = decode_cpcache_index(which, true);
393 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
394 return e->appendix_if_resolved(cpool);
395 }
398 bool ConstantPool::has_method_type_at_if_loaded(constantPoolHandle cpool, int which) {
399 if (cpool->cache() == NULL) return false; // nothing to load yet
400 int cache_index = decode_cpcache_index(which, true);
401 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
402 return e->has_method_type();
403 }
405 oop ConstantPool::method_type_at_if_loaded(constantPoolHandle cpool, int which) {
406 if (cpool->cache() == NULL) return NULL; // nothing to load yet
407 int cache_index = decode_cpcache_index(which, true);
408 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
409 return e->method_type_if_resolved(cpool);
410 }
413 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
414 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
415 return symbol_at(name_index);
416 }
419 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
420 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
421 return symbol_at(signature_index);
422 }
425 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
426 int i = which;
427 if (!uncached && cache() != NULL) {
428 if (ConstantPool::is_invokedynamic_index(which)) {
429 // Invokedynamic index is index into resolved_references
430 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
431 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
432 assert(tag_at(pool_index).is_name_and_type(), "");
433 return pool_index;
434 }
435 // change byte-ordering and go via cache
436 i = remap_instruction_operand_from_cache(which);
437 } else {
438 if (tag_at(which).is_invoke_dynamic()) {
439 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
440 assert(tag_at(pool_index).is_name_and_type(), "");
441 return pool_index;
442 }
443 }
444 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
445 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
446 jint ref_index = *int_at_addr(i);
447 return extract_high_short_from_int(ref_index);
448 }
451 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
452 guarantee(!ConstantPool::is_invokedynamic_index(which),
453 "an invokedynamic instruction does not have a klass");
454 int i = which;
455 if (!uncached && cache() != NULL) {
456 // change byte-ordering and go via cache
457 i = remap_instruction_operand_from_cache(which);
458 }
459 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
460 jint ref_index = *int_at_addr(i);
461 return extract_low_short_from_int(ref_index);
462 }
466 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
467 int cpc_index = operand;
468 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
469 assert((int)(u2)cpc_index == cpc_index, "clean u2");
470 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
471 return member_index;
472 }
475 void ConstantPool::verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle k, TRAPS) {
476 if (k->oop_is_instance() || k->oop_is_objArray()) {
477 instanceKlassHandle holder (THREAD, this_oop->pool_holder());
478 Klass* elem_oop = k->oop_is_instance() ? k() : ObjArrayKlass::cast(k())->bottom_klass();
479 KlassHandle element (THREAD, elem_oop);
481 // The element type could be a typeArray - we only need the access check if it is
482 // an reference to another class
483 if (element->oop_is_instance()) {
484 LinkResolver::check_klass_accessability(holder, element, CHECK);
485 }
486 }
487 }
490 int ConstantPool::name_ref_index_at(int which_nt) {
491 jint ref_index = name_and_type_at(which_nt);
492 return extract_low_short_from_int(ref_index);
493 }
496 int ConstantPool::signature_ref_index_at(int which_nt) {
497 jint ref_index = name_and_type_at(which_nt);
498 return extract_high_short_from_int(ref_index);
499 }
502 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
503 return klass_at(klass_ref_index_at(which), THREAD);
504 }
507 Symbol* ConstantPool::klass_name_at(int which) {
508 assert(tag_at(which).is_unresolved_klass() || tag_at(which).is_klass(),
509 "Corrupted constant pool");
510 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
511 // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
512 // tag is not updated atomicly.
513 CPSlot entry = slot_at(which);
514 if (entry.is_resolved()) {
515 // Already resolved - return entry's name.
516 assert(entry.get_klass()->is_klass(), "must be");
517 return entry.get_klass()->name();
518 } else {
519 assert(entry.is_unresolved(), "must be either symbol or klass");
520 return entry.get_symbol();
521 }
522 }
524 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
525 jint ref_index = klass_ref_index_at(which);
526 return klass_at_noresolve(ref_index);
527 }
529 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
530 jint ref_index = uncached_klass_ref_index_at(which);
531 return klass_at_noresolve(ref_index);
532 }
534 char* ConstantPool::string_at_noresolve(int which) {
535 Symbol* s = unresolved_string_at(which);
536 if (s == NULL) {
537 return (char*)"<pseudo-string>";
538 } else {
539 return unresolved_string_at(which)->as_C_string();
540 }
541 }
543 BasicType ConstantPool::basic_type_for_signature_at(int which) {
544 return FieldType::basic_type(symbol_at(which));
545 }
548 void ConstantPool::resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS) {
549 for (int index = 1; index < this_oop->length(); index++) { // Index 0 is unused
550 if (this_oop->tag_at(index).is_string()) {
551 this_oop->string_at(index, CHECK);
552 }
553 }
554 }
556 // Resolve all the classes in the constant pool. If they are all resolved,
557 // the constant pool is read-only. Enhancement: allocate cp entries to
558 // another metaspace, and copy to read-only or read-write space if this
559 // bit is set.
560 bool ConstantPool::resolve_class_constants(TRAPS) {
561 constantPoolHandle cp(THREAD, this);
562 for (int index = 1; index < length(); index++) { // Index 0 is unused
563 if (tag_at(index).is_unresolved_klass() &&
564 klass_at_if_loaded(cp, index) == NULL) {
565 return false;
566 }
567 }
568 // set_preresolution(); or some bit for future use
569 return true;
570 }
572 Symbol* ConstantPool::exception_message(constantPoolHandle this_oop, int which, constantTag tag, oop pending_exception) {
573 // Dig out the detailed message to reuse if possible
574 Symbol* message = NULL;
575 oop detailed_message = java_lang_Throwable::message(pending_exception);
576 if (detailed_message != NULL) {
577 message = java_lang_String::as_symbol_or_null(detailed_message);
578 if (message != NULL) {
579 return message;
580 }
581 }
583 // Return specific message for the tag
584 switch (tag.value()) {
585 case JVM_CONSTANT_UnresolvedClass:
586 // return the class name in the error message
587 message = this_oop->unresolved_klass_at(which);
588 break;
589 case JVM_CONSTANT_MethodHandle:
590 // return the method handle name in the error message
591 message = this_oop->method_handle_name_ref_at(which);
592 break;
593 case JVM_CONSTANT_MethodType:
594 // return the method type signature in the error message
595 message = this_oop->method_type_signature_at(which);
596 break;
597 default:
598 ShouldNotReachHere();
599 }
601 return message;
602 }
604 void ConstantPool::throw_resolution_error(constantPoolHandle this_oop, int which, TRAPS) {
605 Symbol* message = NULL;
606 Symbol* error = SystemDictionary::find_resolution_error(this_oop, which, &message);
607 assert(error != NULL && message != NULL, "checking");
608 CLEAR_PENDING_EXCEPTION;
609 ResourceMark rm;
610 THROW_MSG(error, message->as_C_string());
611 }
613 // If resolution for Class, MethodHandle or MethodType fails, save the exception
614 // in the resolution error table, so that the same exception is thrown again.
615 void ConstantPool::save_and_throw_exception(constantPoolHandle this_oop, int which,
616 constantTag tag, TRAPS) {
617 assert(this_oop->lock()->is_locked(), "constant pool lock should be held");
618 Symbol* error = PENDING_EXCEPTION->klass()->name();
620 int error_tag = tag.error_value();
622 if (!PENDING_EXCEPTION->
623 is_a(SystemDictionary::LinkageError_klass())) {
624 // Just throw the exception and don't prevent these classes from
625 // being loaded due to virtual machine errors like StackOverflow
626 // and OutOfMemoryError, etc, or if the thread was hit by stop()
627 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
628 } else if (this_oop->tag_at(which).value() != error_tag) {
629 Symbol* message = exception_message(this_oop, which, tag, PENDING_EXCEPTION);
630 SystemDictionary::add_resolution_error(this_oop, which, error, message);
631 this_oop->tag_at_put(which, error_tag);
632 } else {
633 // some other thread put this in error state
634 throw_resolution_error(this_oop, which, CHECK);
635 }
637 // This exits with some pending exception
638 assert(HAS_PENDING_EXCEPTION, "should not be cleared");
639 }
643 // Called to resolve constants in the constant pool and return an oop.
644 // Some constant pool entries cache their resolved oop. This is also
645 // called to create oops from constants to use in arguments for invokedynamic
646 oop ConstantPool::resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS) {
647 oop result_oop = NULL;
648 Handle throw_exception;
650 if (cache_index == _possible_index_sentinel) {
651 // It is possible that this constant is one which is cached in the objects.
652 // We'll do a linear search. This should be OK because this usage is rare.
653 assert(index > 0, "valid index");
654 cache_index = this_oop->cp_to_object_index(index);
655 }
656 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
657 assert(index == _no_index_sentinel || index >= 0, "");
659 if (cache_index >= 0) {
660 result_oop = this_oop->resolved_references()->obj_at(cache_index);
661 if (result_oop != NULL) {
662 return result_oop;
663 // That was easy...
664 }
665 index = this_oop->object_to_cp_index(cache_index);
666 }
668 jvalue prim_value; // temp used only in a few cases below
670 constantTag tag = this_oop->tag_at(index);
672 switch (tag.value()) {
674 case JVM_CONSTANT_UnresolvedClass:
675 case JVM_CONSTANT_UnresolvedClassInError:
676 case JVM_CONSTANT_Class:
677 {
678 assert(cache_index == _no_index_sentinel, "should not have been set");
679 Klass* resolved = klass_at_impl(this_oop, index, CHECK_NULL);
680 // ldc wants the java mirror.
681 result_oop = resolved->java_mirror();
682 break;
683 }
685 case JVM_CONSTANT_String:
686 assert(cache_index != _no_index_sentinel, "should have been set");
687 if (this_oop->is_pseudo_string_at(index)) {
688 result_oop = this_oop->pseudo_string_at(index, cache_index);
689 break;
690 }
691 result_oop = string_at_impl(this_oop, index, cache_index, CHECK_NULL);
692 break;
694 case JVM_CONSTANT_MethodHandleInError:
695 case JVM_CONSTANT_MethodTypeInError:
696 {
697 throw_resolution_error(this_oop, index, CHECK_NULL);
698 break;
699 }
701 case JVM_CONSTANT_MethodHandle:
702 {
703 int ref_kind = this_oop->method_handle_ref_kind_at(index);
704 int callee_index = this_oop->method_handle_klass_index_at(index);
705 Symbol* name = this_oop->method_handle_name_ref_at(index);
706 Symbol* signature = this_oop->method_handle_signature_ref_at(index);
707 if (PrintMiscellaneous)
708 tty->print_cr("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
709 ref_kind, index, this_oop->method_handle_index_at(index),
710 callee_index, name->as_C_string(), signature->as_C_string());
711 KlassHandle callee;
712 { Klass* k = klass_at_impl(this_oop, callee_index, CHECK_NULL);
713 callee = KlassHandle(THREAD, k);
714 }
715 KlassHandle klass(THREAD, this_oop->pool_holder());
716 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
717 callee, name, signature,
718 THREAD);
719 result_oop = value();
720 if (HAS_PENDING_EXCEPTION) {
721 MonitorLockerEx ml(this_oop->lock()); // lock cpool to change tag.
722 save_and_throw_exception(this_oop, index, tag, CHECK_NULL);
723 }
724 break;
725 }
727 case JVM_CONSTANT_MethodType:
728 {
729 Symbol* signature = this_oop->method_type_signature_at(index);
730 if (PrintMiscellaneous)
731 tty->print_cr("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
732 index, this_oop->method_type_index_at(index),
733 signature->as_C_string());
734 KlassHandle klass(THREAD, this_oop->pool_holder());
735 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
736 result_oop = value();
737 if (HAS_PENDING_EXCEPTION) {
738 MonitorLockerEx ml(this_oop->lock()); // lock cpool to change tag.
739 save_and_throw_exception(this_oop, index, tag, CHECK_NULL);
740 }
741 break;
742 }
744 case JVM_CONSTANT_Integer:
745 assert(cache_index == _no_index_sentinel, "should not have been set");
746 prim_value.i = this_oop->int_at(index);
747 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
748 break;
750 case JVM_CONSTANT_Float:
751 assert(cache_index == _no_index_sentinel, "should not have been set");
752 prim_value.f = this_oop->float_at(index);
753 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
754 break;
756 case JVM_CONSTANT_Long:
757 assert(cache_index == _no_index_sentinel, "should not have been set");
758 prim_value.j = this_oop->long_at(index);
759 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
760 break;
762 case JVM_CONSTANT_Double:
763 assert(cache_index == _no_index_sentinel, "should not have been set");
764 prim_value.d = this_oop->double_at(index);
765 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
766 break;
768 default:
769 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
770 this_oop(), index, cache_index, tag.value()));
771 assert(false, "unexpected constant tag");
772 break;
773 }
775 if (cache_index >= 0) {
776 // Cache the oop here also.
777 Handle result_handle(THREAD, result_oop);
778 MonitorLockerEx ml(this_oop->lock()); // don't know if we really need this
779 oop result = this_oop->resolved_references()->obj_at(cache_index);
780 // Benign race condition: resolved_references may already be filled in while we were trying to lock.
781 // The important thing here is that all threads pick up the same result.
782 // It doesn't matter which racing thread wins, as long as only one
783 // result is used by all threads, and all future queries.
784 // That result may be either a resolved constant or a failure exception.
785 if (result == NULL) {
786 this_oop->resolved_references()->obj_at_put(cache_index, result_handle());
787 return result_handle();
788 } else {
789 // Return the winning thread's result. This can be different than
790 // result_handle() for MethodHandles.
791 return result;
792 }
793 } else {
794 return result_oop;
795 }
796 }
798 oop ConstantPool::uncached_string_at(int which, TRAPS) {
799 Symbol* sym = unresolved_string_at(which);
800 oop str = StringTable::intern(sym, CHECK_(NULL));
801 assert(java_lang_String::is_instance(str), "must be string");
802 return str;
803 }
806 oop ConstantPool::resolve_bootstrap_specifier_at_impl(constantPoolHandle this_oop, int index, TRAPS) {
807 assert(this_oop->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
809 Handle bsm;
810 int argc;
811 {
812 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
813 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
814 // It is accompanied by the optional arguments.
815 int bsm_index = this_oop->invoke_dynamic_bootstrap_method_ref_index_at(index);
816 oop bsm_oop = this_oop->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
817 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
818 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
819 }
821 // Extract the optional static arguments.
822 argc = this_oop->invoke_dynamic_argument_count_at(index);
823 if (argc == 0) return bsm_oop;
825 bsm = Handle(THREAD, bsm_oop);
826 }
828 objArrayHandle info;
829 {
830 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
831 info = objArrayHandle(THREAD, info_oop);
832 }
834 info->obj_at_put(0, bsm());
835 for (int i = 0; i < argc; i++) {
836 int arg_index = this_oop->invoke_dynamic_argument_index_at(index, i);
837 oop arg_oop = this_oop->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
838 info->obj_at_put(1+i, arg_oop);
839 }
841 return info();
842 }
844 oop ConstantPool::string_at_impl(constantPoolHandle this_oop, int which, int obj_index, TRAPS) {
845 // If the string has already been interned, this entry will be non-null
846 oop str = this_oop->resolved_references()->obj_at(obj_index);
847 if (str != NULL) return str;
848 Symbol* sym = this_oop->unresolved_string_at(which);
849 str = StringTable::intern(sym, CHECK_(NULL));
850 this_oop->string_at_put(which, obj_index, str);
851 assert(java_lang_String::is_instance(str), "must be string");
852 return str;
853 }
856 bool ConstantPool::klass_name_at_matches(instanceKlassHandle k,
857 int which) {
858 // Names are interned, so we can compare Symbol*s directly
859 Symbol* cp_name = klass_name_at(which);
860 return (cp_name == k->name());
861 }
864 // Iterate over symbols and decrement ones which are Symbol*s.
865 // This is done during GC so do not need to lock constantPool unless we
866 // have per-thread safepoints.
867 // Only decrement the UTF8 symbols. Unresolved classes and strings point to
868 // these symbols but didn't increment the reference count.
869 void ConstantPool::unreference_symbols() {
870 for (int index = 1; index < length(); index++) { // Index 0 is unused
871 constantTag tag = tag_at(index);
872 if (tag.is_symbol()) {
873 symbol_at(index)->decrement_refcount();
874 }
875 }
876 }
879 // Compare this constant pool's entry at index1 to the constant pool
880 // cp2's entry at index2.
881 bool ConstantPool::compare_entry_to(int index1, constantPoolHandle cp2,
882 int index2, TRAPS) {
884 // The error tags are equivalent to non-error tags when comparing
885 jbyte t1 = tag_at(index1).non_error_value();
886 jbyte t2 = cp2->tag_at(index2).non_error_value();
888 if (t1 != t2) {
889 // Not the same entry type so there is nothing else to check. Note
890 // that this style of checking will consider resolved/unresolved
891 // class pairs as different.
892 // From the ConstantPool* API point of view, this is correct
893 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
894 // plays out in the context of ConstantPool* merging.
895 return false;
896 }
898 switch (t1) {
899 case JVM_CONSTANT_Class:
900 {
901 Klass* k1 = klass_at(index1, CHECK_false);
902 Klass* k2 = cp2->klass_at(index2, CHECK_false);
903 if (k1 == k2) {
904 return true;
905 }
906 } break;
908 case JVM_CONSTANT_ClassIndex:
909 {
910 int recur1 = klass_index_at(index1);
911 int recur2 = cp2->klass_index_at(index2);
912 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
913 if (match) {
914 return true;
915 }
916 } break;
918 case JVM_CONSTANT_Double:
919 {
920 jdouble d1 = double_at(index1);
921 jdouble d2 = cp2->double_at(index2);
922 if (d1 == d2) {
923 return true;
924 }
925 } break;
927 case JVM_CONSTANT_Fieldref:
928 case JVM_CONSTANT_InterfaceMethodref:
929 case JVM_CONSTANT_Methodref:
930 {
931 int recur1 = uncached_klass_ref_index_at(index1);
932 int recur2 = cp2->uncached_klass_ref_index_at(index2);
933 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
934 if (match) {
935 recur1 = uncached_name_and_type_ref_index_at(index1);
936 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
937 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
938 if (match) {
939 return true;
940 }
941 }
942 } break;
944 case JVM_CONSTANT_Float:
945 {
946 jfloat f1 = float_at(index1);
947 jfloat f2 = cp2->float_at(index2);
948 if (f1 == f2) {
949 return true;
950 }
951 } break;
953 case JVM_CONSTANT_Integer:
954 {
955 jint i1 = int_at(index1);
956 jint i2 = cp2->int_at(index2);
957 if (i1 == i2) {
958 return true;
959 }
960 } break;
962 case JVM_CONSTANT_Long:
963 {
964 jlong l1 = long_at(index1);
965 jlong l2 = cp2->long_at(index2);
966 if (l1 == l2) {
967 return true;
968 }
969 } break;
971 case JVM_CONSTANT_NameAndType:
972 {
973 int recur1 = name_ref_index_at(index1);
974 int recur2 = cp2->name_ref_index_at(index2);
975 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
976 if (match) {
977 recur1 = signature_ref_index_at(index1);
978 recur2 = cp2->signature_ref_index_at(index2);
979 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
980 if (match) {
981 return true;
982 }
983 }
984 } break;
986 case JVM_CONSTANT_StringIndex:
987 {
988 int recur1 = string_index_at(index1);
989 int recur2 = cp2->string_index_at(index2);
990 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
991 if (match) {
992 return true;
993 }
994 } break;
996 case JVM_CONSTANT_UnresolvedClass:
997 {
998 Symbol* k1 = unresolved_klass_at(index1);
999 Symbol* k2 = cp2->unresolved_klass_at(index2);
1000 if (k1 == k2) {
1001 return true;
1002 }
1003 } break;
1005 case JVM_CONSTANT_MethodType:
1006 {
1007 int k1 = method_type_index_at_error_ok(index1);
1008 int k2 = cp2->method_type_index_at_error_ok(index2);
1009 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1010 if (match) {
1011 return true;
1012 }
1013 } break;
1015 case JVM_CONSTANT_MethodHandle:
1016 {
1017 int k1 = method_handle_ref_kind_at_error_ok(index1);
1018 int k2 = cp2->method_handle_ref_kind_at_error_ok(index2);
1019 if (k1 == k2) {
1020 int i1 = method_handle_index_at_error_ok(index1);
1021 int i2 = cp2->method_handle_index_at_error_ok(index2);
1022 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1023 if (match) {
1024 return true;
1025 }
1026 }
1027 } break;
1029 case JVM_CONSTANT_InvokeDynamic:
1030 {
1031 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1032 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1033 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1034 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1035 // separate statements and variables because CHECK_false is used
1036 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1037 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1038 return (match_entry && match_operand);
1039 } break;
1041 case JVM_CONSTANT_String:
1042 {
1043 Symbol* s1 = unresolved_string_at(index1);
1044 Symbol* s2 = cp2->unresolved_string_at(index2);
1045 if (s1 == s2) {
1046 return true;
1047 }
1048 } break;
1050 case JVM_CONSTANT_Utf8:
1051 {
1052 Symbol* s1 = symbol_at(index1);
1053 Symbol* s2 = cp2->symbol_at(index2);
1054 if (s1 == s2) {
1055 return true;
1056 }
1057 } break;
1059 // Invalid is used as the tag for the second constant pool entry
1060 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1061 // not be seen by itself.
1062 case JVM_CONSTANT_Invalid: // fall through
1064 default:
1065 ShouldNotReachHere();
1066 break;
1067 }
1069 return false;
1070 } // end compare_entry_to()
1073 // Resize the operands array with delta_len and delta_size.
1074 // Used in RedefineClasses for CP merge.
1075 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1076 int old_len = operand_array_length(operands());
1077 int new_len = old_len + delta_len;
1078 int min_len = (delta_len > 0) ? old_len : new_len;
1080 int old_size = operands()->length();
1081 int new_size = old_size + delta_size;
1082 int min_size = (delta_size > 0) ? old_size : new_size;
1084 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1085 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1087 // Set index in the resized array for existing elements only
1088 for (int idx = 0; idx < min_len; idx++) {
1089 int offset = operand_offset_at(idx); // offset in original array
1090 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1091 }
1092 // Copy the bootstrap specifiers only
1093 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1094 new_ops->adr_at(2*new_len),
1095 (min_size - 2*min_len) * sizeof(u2));
1096 // Explicitly deallocate old operands array.
1097 // Note, it is not needed for 7u backport.
1098 if ( operands() != NULL) { // the safety check
1099 MetadataFactory::free_array<u2>(loader_data, operands());
1100 }
1101 set_operands(new_ops);
1102 } // end resize_operands()
1105 // Extend the operands array with the length and size of the ext_cp operands.
1106 // Used in RedefineClasses for CP merge.
1107 void ConstantPool::extend_operands(constantPoolHandle ext_cp, TRAPS) {
1108 int delta_len = operand_array_length(ext_cp->operands());
1109 if (delta_len == 0) {
1110 return; // nothing to do
1111 }
1112 int delta_size = ext_cp->operands()->length();
1114 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1116 if (operand_array_length(operands()) == 0) {
1117 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1118 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1119 // The first element index defines the offset of second part
1120 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1121 set_operands(new_ops);
1122 } else {
1123 resize_operands(delta_len, delta_size, CHECK);
1124 }
1126 } // end extend_operands()
1129 // Shrink the operands array to a smaller array with new_len length.
1130 // Used in RedefineClasses for CP merge.
1131 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1132 int old_len = operand_array_length(operands());
1133 if (new_len == old_len) {
1134 return; // nothing to do
1135 }
1136 assert(new_len < old_len, "shrunken operands array must be smaller");
1138 int free_base = operand_next_offset_at(new_len - 1);
1139 int delta_len = new_len - old_len;
1140 int delta_size = 2*delta_len + free_base - operands()->length();
1142 resize_operands(delta_len, delta_size, CHECK);
1144 } // end shrink_operands()
1147 void ConstantPool::copy_operands(constantPoolHandle from_cp,
1148 constantPoolHandle to_cp,
1149 TRAPS) {
1151 int from_oplen = operand_array_length(from_cp->operands());
1152 int old_oplen = operand_array_length(to_cp->operands());
1153 if (from_oplen != 0) {
1154 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1155 // append my operands to the target's operands array
1156 if (old_oplen == 0) {
1157 // Can't just reuse from_cp's operand list because of deallocation issues
1158 int len = from_cp->operands()->length();
1159 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1160 Copy::conjoint_memory_atomic(
1161 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1162 to_cp->set_operands(new_ops);
1163 } else {
1164 int old_len = to_cp->operands()->length();
1165 int from_len = from_cp->operands()->length();
1166 int old_off = old_oplen * sizeof(u2);
1167 int from_off = from_oplen * sizeof(u2);
1168 // Use the metaspace for the destination constant pool
1169 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1170 int fillp = 0, len = 0;
1171 // first part of dest
1172 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1173 new_operands->adr_at(fillp),
1174 (len = old_off) * sizeof(u2));
1175 fillp += len;
1176 // first part of src
1177 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1178 new_operands->adr_at(fillp),
1179 (len = from_off) * sizeof(u2));
1180 fillp += len;
1181 // second part of dest
1182 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1183 new_operands->adr_at(fillp),
1184 (len = old_len - old_off) * sizeof(u2));
1185 fillp += len;
1186 // second part of src
1187 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1188 new_operands->adr_at(fillp),
1189 (len = from_len - from_off) * sizeof(u2));
1190 fillp += len;
1191 assert(fillp == new_operands->length(), "");
1193 // Adjust indexes in the first part of the copied operands array.
1194 for (int j = 0; j < from_oplen; j++) {
1195 int offset = operand_offset_at(new_operands, old_oplen + j);
1196 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1197 offset += old_len; // every new tuple is preceded by old_len extra u2's
1198 operand_offset_at_put(new_operands, old_oplen + j, offset);
1199 }
1201 // replace target operands array with combined array
1202 to_cp->set_operands(new_operands);
1203 }
1204 }
1205 } // end copy_operands()
1208 // Copy this constant pool's entries at start_i to end_i (inclusive)
1209 // to the constant pool to_cp's entries starting at to_i. A total of
1210 // (end_i - start_i) + 1 entries are copied.
1211 void ConstantPool::copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i,
1212 constantPoolHandle to_cp, int to_i, TRAPS) {
1215 int dest_i = to_i; // leave original alone for debug purposes
1217 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1218 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1220 switch (from_cp->tag_at(src_i).value()) {
1221 case JVM_CONSTANT_Double:
1222 case JVM_CONSTANT_Long:
1223 // double and long take two constant pool entries
1224 src_i += 2;
1225 dest_i += 2;
1226 break;
1228 default:
1229 // all others take one constant pool entry
1230 src_i++;
1231 dest_i++;
1232 break;
1233 }
1234 }
1235 copy_operands(from_cp, to_cp, CHECK);
1237 } // end copy_cp_to_impl()
1240 // Copy this constant pool's entry at from_i to the constant pool
1241 // to_cp's entry at to_i.
1242 void ConstantPool::copy_entry_to(constantPoolHandle from_cp, int from_i,
1243 constantPoolHandle to_cp, int to_i,
1244 TRAPS) {
1246 int tag = from_cp->tag_at(from_i).value();
1247 switch (tag) {
1248 case JVM_CONSTANT_Class:
1249 {
1250 Klass* k = from_cp->klass_at(from_i, CHECK);
1251 to_cp->klass_at_put(to_i, k);
1252 } break;
1254 case JVM_CONSTANT_ClassIndex:
1255 {
1256 jint ki = from_cp->klass_index_at(from_i);
1257 to_cp->klass_index_at_put(to_i, ki);
1258 } break;
1260 case JVM_CONSTANT_Double:
1261 {
1262 jdouble d = from_cp->double_at(from_i);
1263 to_cp->double_at_put(to_i, d);
1264 // double takes two constant pool entries so init second entry's tag
1265 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1266 } break;
1268 case JVM_CONSTANT_Fieldref:
1269 {
1270 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1271 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1272 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1273 } break;
1275 case JVM_CONSTANT_Float:
1276 {
1277 jfloat f = from_cp->float_at(from_i);
1278 to_cp->float_at_put(to_i, f);
1279 } break;
1281 case JVM_CONSTANT_Integer:
1282 {
1283 jint i = from_cp->int_at(from_i);
1284 to_cp->int_at_put(to_i, i);
1285 } break;
1287 case JVM_CONSTANT_InterfaceMethodref:
1288 {
1289 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1290 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1291 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1292 } break;
1294 case JVM_CONSTANT_Long:
1295 {
1296 jlong l = from_cp->long_at(from_i);
1297 to_cp->long_at_put(to_i, l);
1298 // long takes two constant pool entries so init second entry's tag
1299 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1300 } break;
1302 case JVM_CONSTANT_Methodref:
1303 {
1304 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1305 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1306 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1307 } break;
1309 case JVM_CONSTANT_NameAndType:
1310 {
1311 int name_ref_index = from_cp->name_ref_index_at(from_i);
1312 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1313 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1314 } break;
1316 case JVM_CONSTANT_StringIndex:
1317 {
1318 jint si = from_cp->string_index_at(from_i);
1319 to_cp->string_index_at_put(to_i, si);
1320 } break;
1322 case JVM_CONSTANT_UnresolvedClass:
1323 case JVM_CONSTANT_UnresolvedClassInError:
1324 {
1325 // Can be resolved after checking tag, so check the slot first.
1326 CPSlot entry = from_cp->slot_at(from_i);
1327 if (entry.is_resolved()) {
1328 assert(entry.get_klass()->is_klass(), "must be");
1329 // Already resolved
1330 to_cp->klass_at_put(to_i, entry.get_klass());
1331 } else {
1332 to_cp->unresolved_klass_at_put(to_i, entry.get_symbol());
1333 }
1334 } break;
1336 case JVM_CONSTANT_String:
1337 {
1338 Symbol* s = from_cp->unresolved_string_at(from_i);
1339 to_cp->unresolved_string_at_put(to_i, s);
1340 } break;
1342 case JVM_CONSTANT_Utf8:
1343 {
1344 Symbol* s = from_cp->symbol_at(from_i);
1345 // Need to increase refcount, the old one will be thrown away and deferenced
1346 s->increment_refcount();
1347 to_cp->symbol_at_put(to_i, s);
1348 } break;
1350 case JVM_CONSTANT_MethodType:
1351 case JVM_CONSTANT_MethodTypeInError:
1352 {
1353 jint k = from_cp->method_type_index_at_error_ok(from_i);
1354 to_cp->method_type_index_at_put(to_i, k);
1355 } break;
1357 case JVM_CONSTANT_MethodHandle:
1358 case JVM_CONSTANT_MethodHandleInError:
1359 {
1360 int k1 = from_cp->method_handle_ref_kind_at_error_ok(from_i);
1361 int k2 = from_cp->method_handle_index_at_error_ok(from_i);
1362 to_cp->method_handle_index_at_put(to_i, k1, k2);
1363 } break;
1365 case JVM_CONSTANT_InvokeDynamic:
1366 {
1367 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1368 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1369 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1370 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1371 } break;
1373 // Invalid is used as the tag for the second constant pool entry
1374 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1375 // not be seen by itself.
1376 case JVM_CONSTANT_Invalid: // fall through
1378 default:
1379 {
1380 ShouldNotReachHere();
1381 } break;
1382 }
1383 } // end copy_entry_to()
1386 // Search constant pool search_cp for an entry that matches this
1387 // constant pool's entry at pattern_i. Returns the index of a
1388 // matching entry or zero (0) if there is no matching entry.
1389 int ConstantPool::find_matching_entry(int pattern_i,
1390 constantPoolHandle search_cp, TRAPS) {
1392 // index zero (0) is not used
1393 for (int i = 1; i < search_cp->length(); i++) {
1394 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1395 if (found) {
1396 return i;
1397 }
1398 }
1400 return 0; // entry not found; return unused index zero (0)
1401 } // end find_matching_entry()
1404 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1405 // cp2's bootstrap specifier at idx2.
1406 bool ConstantPool::compare_operand_to(int idx1, constantPoolHandle cp2, int idx2, TRAPS) {
1407 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1408 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1409 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1411 if (!match) {
1412 return false;
1413 }
1414 int argc = operand_argument_count_at(idx1);
1415 if (argc == cp2->operand_argument_count_at(idx2)) {
1416 for (int j = 0; j < argc; j++) {
1417 k1 = operand_argument_index_at(idx1, j);
1418 k2 = cp2->operand_argument_index_at(idx2, j);
1419 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1420 if (!match) {
1421 return false;
1422 }
1423 }
1424 return true; // got through loop; all elements equal
1425 }
1426 return false;
1427 } // end compare_operand_to()
1429 // Search constant pool search_cp for a bootstrap specifier that matches
1430 // this constant pool's bootstrap specifier at pattern_i index.
1431 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1432 int ConstantPool::find_matching_operand(int pattern_i,
1433 constantPoolHandle search_cp, int search_len, TRAPS) {
1434 for (int i = 0; i < search_len; i++) {
1435 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1436 if (found) {
1437 return i;
1438 }
1439 }
1440 return -1; // bootstrap specifier not found; return unused index (-1)
1441 } // end find_matching_operand()
1444 #ifndef PRODUCT
1446 const char* ConstantPool::printable_name_at(int which) {
1448 constantTag tag = tag_at(which);
1450 if (tag.is_string()) {
1451 return string_at_noresolve(which);
1452 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1453 return klass_name_at(which)->as_C_string();
1454 } else if (tag.is_symbol()) {
1455 return symbol_at(which)->as_C_string();
1456 }
1457 return "";
1458 }
1460 #endif // PRODUCT
1463 // JVMTI GetConstantPool support
1465 // For debugging of constant pool
1466 const bool debug_cpool = false;
1468 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1470 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1471 const char* WARN_MSG = "Must not be such entry!";
1472 jint size = 0;
1473 u2 idx1, idx2;
1475 for (jint idx = 1; idx < cnt; idx++) {
1476 jint ent_size = 0;
1477 u1 tag = *bytes++;
1478 size++; // count tag
1480 printf("const #%03d, tag: %02d ", idx, tag);
1481 switch(tag) {
1482 case JVM_CONSTANT_Invalid: {
1483 printf("Invalid");
1484 break;
1485 }
1486 case JVM_CONSTANT_Unicode: {
1487 printf("Unicode %s", WARN_MSG);
1488 break;
1489 }
1490 case JVM_CONSTANT_Utf8: {
1491 u2 len = Bytes::get_Java_u2(bytes);
1492 char str[128];
1493 if (len > 127) {
1494 len = 127;
1495 }
1496 strncpy(str, (char *) (bytes+2), len);
1497 str[len] = '\0';
1498 printf("Utf8 \"%s\"", str);
1499 ent_size = 2 + len;
1500 break;
1501 }
1502 case JVM_CONSTANT_Integer: {
1503 u4 val = Bytes::get_Java_u4(bytes);
1504 printf("int %d", *(int *) &val);
1505 ent_size = 4;
1506 break;
1507 }
1508 case JVM_CONSTANT_Float: {
1509 u4 val = Bytes::get_Java_u4(bytes);
1510 printf("float %5.3ff", *(float *) &val);
1511 ent_size = 4;
1512 break;
1513 }
1514 case JVM_CONSTANT_Long: {
1515 u8 val = Bytes::get_Java_u8(bytes);
1516 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1517 ent_size = 8;
1518 idx++; // Long takes two cpool slots
1519 break;
1520 }
1521 case JVM_CONSTANT_Double: {
1522 u8 val = Bytes::get_Java_u8(bytes);
1523 printf("double %5.3fd", *(jdouble *)&val);
1524 ent_size = 8;
1525 idx++; // Double takes two cpool slots
1526 break;
1527 }
1528 case JVM_CONSTANT_Class: {
1529 idx1 = Bytes::get_Java_u2(bytes);
1530 printf("class #%03d", idx1);
1531 ent_size = 2;
1532 break;
1533 }
1534 case JVM_CONSTANT_String: {
1535 idx1 = Bytes::get_Java_u2(bytes);
1536 printf("String #%03d", idx1);
1537 ent_size = 2;
1538 break;
1539 }
1540 case JVM_CONSTANT_Fieldref: {
1541 idx1 = Bytes::get_Java_u2(bytes);
1542 idx2 = Bytes::get_Java_u2(bytes+2);
1543 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1544 ent_size = 4;
1545 break;
1546 }
1547 case JVM_CONSTANT_Methodref: {
1548 idx1 = Bytes::get_Java_u2(bytes);
1549 idx2 = Bytes::get_Java_u2(bytes+2);
1550 printf("Method #%03d, #%03d", idx1, idx2);
1551 ent_size = 4;
1552 break;
1553 }
1554 case JVM_CONSTANT_InterfaceMethodref: {
1555 idx1 = Bytes::get_Java_u2(bytes);
1556 idx2 = Bytes::get_Java_u2(bytes+2);
1557 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1558 ent_size = 4;
1559 break;
1560 }
1561 case JVM_CONSTANT_NameAndType: {
1562 idx1 = Bytes::get_Java_u2(bytes);
1563 idx2 = Bytes::get_Java_u2(bytes+2);
1564 printf("NameAndType #%03d, #%03d", idx1, idx2);
1565 ent_size = 4;
1566 break;
1567 }
1568 case JVM_CONSTANT_ClassIndex: {
1569 printf("ClassIndex %s", WARN_MSG);
1570 break;
1571 }
1572 case JVM_CONSTANT_UnresolvedClass: {
1573 printf("UnresolvedClass: %s", WARN_MSG);
1574 break;
1575 }
1576 case JVM_CONSTANT_UnresolvedClassInError: {
1577 printf("UnresolvedClassInErr: %s", WARN_MSG);
1578 break;
1579 }
1580 case JVM_CONSTANT_StringIndex: {
1581 printf("StringIndex: %s", WARN_MSG);
1582 break;
1583 }
1584 }
1585 printf(";\n");
1586 bytes += ent_size;
1587 size += ent_size;
1588 }
1589 printf("Cpool size: %d\n", size);
1590 fflush(0);
1591 return;
1592 } /* end print_cpool_bytes */
1595 // Returns size of constant pool entry.
1596 jint ConstantPool::cpool_entry_size(jint idx) {
1597 switch(tag_at(idx).value()) {
1598 case JVM_CONSTANT_Invalid:
1599 case JVM_CONSTANT_Unicode:
1600 return 1;
1602 case JVM_CONSTANT_Utf8:
1603 return 3 + symbol_at(idx)->utf8_length();
1605 case JVM_CONSTANT_Class:
1606 case JVM_CONSTANT_String:
1607 case JVM_CONSTANT_ClassIndex:
1608 case JVM_CONSTANT_UnresolvedClass:
1609 case JVM_CONSTANT_UnresolvedClassInError:
1610 case JVM_CONSTANT_StringIndex:
1611 case JVM_CONSTANT_MethodType:
1612 case JVM_CONSTANT_MethodTypeInError:
1613 return 3;
1615 case JVM_CONSTANT_MethodHandle:
1616 case JVM_CONSTANT_MethodHandleInError:
1617 return 4; //tag, ref_kind, ref_index
1619 case JVM_CONSTANT_Integer:
1620 case JVM_CONSTANT_Float:
1621 case JVM_CONSTANT_Fieldref:
1622 case JVM_CONSTANT_Methodref:
1623 case JVM_CONSTANT_InterfaceMethodref:
1624 case JVM_CONSTANT_NameAndType:
1625 return 5;
1627 case JVM_CONSTANT_InvokeDynamic:
1628 // u1 tag, u2 bsm, u2 nt
1629 return 5;
1631 case JVM_CONSTANT_Long:
1632 case JVM_CONSTANT_Double:
1633 return 9;
1634 }
1635 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1636 return 1;
1637 } /* end cpool_entry_size */
1640 // SymbolHashMap is used to find a constant pool index from a string.
1641 // This function fills in SymbolHashMaps, one for utf8s and one for
1642 // class names, returns size of the cpool raw bytes.
1643 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1644 SymbolHashMap *classmap) {
1645 jint size = 0;
1647 for (u2 idx = 1; idx < length(); idx++) {
1648 u2 tag = tag_at(idx).value();
1649 size += cpool_entry_size(idx);
1651 switch(tag) {
1652 case JVM_CONSTANT_Utf8: {
1653 Symbol* sym = symbol_at(idx);
1654 symmap->add_entry(sym, idx);
1655 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1656 break;
1657 }
1658 case JVM_CONSTANT_Class:
1659 case JVM_CONSTANT_UnresolvedClass:
1660 case JVM_CONSTANT_UnresolvedClassInError: {
1661 Symbol* sym = klass_name_at(idx);
1662 classmap->add_entry(sym, idx);
1663 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1664 break;
1665 }
1666 case JVM_CONSTANT_Long:
1667 case JVM_CONSTANT_Double: {
1668 idx++; // Both Long and Double take two cpool slots
1669 break;
1670 }
1671 }
1672 }
1673 return size;
1674 } /* end hash_utf8_entries_to */
1677 // Copy cpool bytes.
1678 // Returns:
1679 // 0, in case of OutOfMemoryError
1680 // -1, in case of internal error
1681 // > 0, count of the raw cpool bytes that have been copied
1682 int ConstantPool::copy_cpool_bytes(int cpool_size,
1683 SymbolHashMap* tbl,
1684 unsigned char *bytes) {
1685 u2 idx1, idx2;
1686 jint size = 0;
1687 jint cnt = length();
1688 unsigned char *start_bytes = bytes;
1690 for (jint idx = 1; idx < cnt; idx++) {
1691 u1 tag = tag_at(idx).value();
1692 jint ent_size = cpool_entry_size(idx);
1694 assert(size + ent_size <= cpool_size, "Size mismatch");
1696 *bytes = tag;
1697 DBG(printf("#%03hd tag=%03hd, ", idx, tag));
1698 switch(tag) {
1699 case JVM_CONSTANT_Invalid: {
1700 DBG(printf("JVM_CONSTANT_Invalid"));
1701 break;
1702 }
1703 case JVM_CONSTANT_Unicode: {
1704 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1705 DBG(printf("JVM_CONSTANT_Unicode"));
1706 break;
1707 }
1708 case JVM_CONSTANT_Utf8: {
1709 Symbol* sym = symbol_at(idx);
1710 char* str = sym->as_utf8();
1711 // Warning! It's crashing on x86 with len = sym->utf8_length()
1712 int len = (int) strlen(str);
1713 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1714 for (int i = 0; i < len; i++) {
1715 bytes[3+i] = (u1) str[i];
1716 }
1717 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1718 break;
1719 }
1720 case JVM_CONSTANT_Integer: {
1721 jint val = int_at(idx);
1722 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1723 break;
1724 }
1725 case JVM_CONSTANT_Float: {
1726 jfloat val = float_at(idx);
1727 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1728 break;
1729 }
1730 case JVM_CONSTANT_Long: {
1731 jlong val = long_at(idx);
1732 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1733 idx++; // Long takes two cpool slots
1734 break;
1735 }
1736 case JVM_CONSTANT_Double: {
1737 jdouble val = double_at(idx);
1738 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1739 idx++; // Double takes two cpool slots
1740 break;
1741 }
1742 case JVM_CONSTANT_Class:
1743 case JVM_CONSTANT_UnresolvedClass:
1744 case JVM_CONSTANT_UnresolvedClassInError: {
1745 *bytes = JVM_CONSTANT_Class;
1746 Symbol* sym = klass_name_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_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1751 break;
1752 }
1753 case JVM_CONSTANT_String: {
1754 *bytes = JVM_CONSTANT_String;
1755 Symbol* sym = unresolved_string_at(idx);
1756 idx1 = tbl->symbol_to_value(sym);
1757 assert(idx1 != 0, "Have not found a hashtable entry");
1758 Bytes::put_Java_u2((address) (bytes+1), idx1);
1759 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1760 break;
1761 }
1762 case JVM_CONSTANT_Fieldref:
1763 case JVM_CONSTANT_Methodref:
1764 case JVM_CONSTANT_InterfaceMethodref: {
1765 idx1 = uncached_klass_ref_index_at(idx);
1766 idx2 = uncached_name_and_type_ref_index_at(idx);
1767 Bytes::put_Java_u2((address) (bytes+1), idx1);
1768 Bytes::put_Java_u2((address) (bytes+3), idx2);
1769 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1770 break;
1771 }
1772 case JVM_CONSTANT_NameAndType: {
1773 idx1 = name_ref_index_at(idx);
1774 idx2 = signature_ref_index_at(idx);
1775 Bytes::put_Java_u2((address) (bytes+1), idx1);
1776 Bytes::put_Java_u2((address) (bytes+3), idx2);
1777 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1778 break;
1779 }
1780 case JVM_CONSTANT_ClassIndex: {
1781 *bytes = JVM_CONSTANT_Class;
1782 idx1 = klass_index_at(idx);
1783 Bytes::put_Java_u2((address) (bytes+1), idx1);
1784 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1785 break;
1786 }
1787 case JVM_CONSTANT_StringIndex: {
1788 *bytes = JVM_CONSTANT_String;
1789 idx1 = string_index_at(idx);
1790 Bytes::put_Java_u2((address) (bytes+1), idx1);
1791 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1792 break;
1793 }
1794 case JVM_CONSTANT_MethodHandle:
1795 case JVM_CONSTANT_MethodHandleInError: {
1796 *bytes = JVM_CONSTANT_MethodHandle;
1797 int kind = method_handle_ref_kind_at_error_ok(idx);
1798 idx1 = method_handle_index_at_error_ok(idx);
1799 *(bytes+1) = (unsigned char) kind;
1800 Bytes::put_Java_u2((address) (bytes+2), idx1);
1801 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1802 break;
1803 }
1804 case JVM_CONSTANT_MethodType:
1805 case JVM_CONSTANT_MethodTypeInError: {
1806 *bytes = JVM_CONSTANT_MethodType;
1807 idx1 = method_type_index_at_error_ok(idx);
1808 Bytes::put_Java_u2((address) (bytes+1), idx1);
1809 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1810 break;
1811 }
1812 case JVM_CONSTANT_InvokeDynamic: {
1813 *bytes = tag;
1814 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1815 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1816 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1817 Bytes::put_Java_u2((address) (bytes+1), idx1);
1818 Bytes::put_Java_u2((address) (bytes+3), idx2);
1819 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1820 break;
1821 }
1822 }
1823 DBG(printf("\n"));
1824 bytes += ent_size;
1825 size += ent_size;
1826 }
1827 assert(size == cpool_size, "Size mismatch");
1829 // Keep temorarily for debugging until it's stable.
1830 DBG(print_cpool_bytes(cnt, start_bytes));
1831 return (int)(bytes - start_bytes);
1832 } /* end copy_cpool_bytes */
1834 #undef DBG
1837 void ConstantPool::set_on_stack(const bool value) {
1838 if (value) {
1839 int old_flags = *const_cast<volatile int *>(&_flags);
1840 while ((old_flags & _on_stack) == 0) {
1841 int new_flags = old_flags | _on_stack;
1842 int result = Atomic::cmpxchg(new_flags, &_flags, old_flags);
1844 if (result == old_flags) {
1845 // Succeeded.
1846 MetadataOnStackMark::record(this, Thread::current());
1847 return;
1848 }
1849 old_flags = result;
1850 }
1851 } else {
1852 // Clearing is done single-threadedly.
1853 _flags &= ~_on_stack;
1854 }
1855 }
1857 // JSR 292 support for patching constant pool oops after the class is linked and
1858 // the oop array for resolved references are created.
1859 // We can't do this during classfile parsing, which is how the other indexes are
1860 // patched. The other patches are applied early for some error checking
1861 // so only defer the pseudo_strings.
1862 void ConstantPool::patch_resolved_references(
1863 GrowableArray<Handle>* cp_patches) {
1864 assert(EnableInvokeDynamic, "");
1865 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
1866 Handle patch = cp_patches->at(index);
1867 if (patch.not_null()) {
1868 assert (tag_at(index).is_string(), "should only be string left");
1869 // Patching a string means pre-resolving it.
1870 // The spelling in the constant pool is ignored.
1871 // The constant reference may be any object whatever.
1872 // If it is not a real interned string, the constant is referred
1873 // to as a "pseudo-string", and must be presented to the CP
1874 // explicitly, because it may require scavenging.
1875 int obj_index = cp_to_object_index(index);
1876 pseudo_string_at_put(index, obj_index, patch());
1877 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
1878 }
1879 }
1880 #ifdef ASSERT
1881 // Ensure that all the patches have been used.
1882 for (int index = 0; index < cp_patches->length(); index++) {
1883 assert(cp_patches->at(index).is_null(),
1884 err_msg("Unused constant pool patch at %d in class file %s",
1885 index,
1886 pool_holder()->external_name()));
1887 }
1888 #endif // ASSERT
1889 }
1891 #ifndef PRODUCT
1893 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
1894 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
1895 guarantee(obj->is_constantPool(), "object must be constant pool");
1896 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
1897 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
1899 for (int i = 0; i< cp->length(); i++) {
1900 if (cp->tag_at(i).is_unresolved_klass()) {
1901 // This will force loading of the class
1902 Klass* klass = cp->klass_at(i, CHECK);
1903 if (klass->oop_is_instance()) {
1904 // Force initialization of class
1905 InstanceKlass::cast(klass)->initialize(CHECK);
1906 }
1907 }
1908 }
1909 }
1911 #endif
1914 // Printing
1916 void ConstantPool::print_on(outputStream* st) const {
1917 EXCEPTION_MARK;
1918 assert(is_constantPool(), "must be constantPool");
1919 st->print_cr("%s", internal_name());
1920 if (flags() != 0) {
1921 st->print(" - flags: 0x%x", flags());
1922 if (has_preresolution()) st->print(" has_preresolution");
1923 if (on_stack()) st->print(" on_stack");
1924 st->cr();
1925 }
1926 if (pool_holder() != NULL) {
1927 st->print_cr(" - holder: " INTPTR_FORMAT, pool_holder());
1928 }
1929 st->print_cr(" - cache: " INTPTR_FORMAT, cache());
1930 st->print_cr(" - resolved_references: " INTPTR_FORMAT, (void *)resolved_references());
1931 st->print_cr(" - reference_map: " INTPTR_FORMAT, reference_map());
1933 for (int index = 1; index < length(); index++) { // Index 0 is unused
1934 ((ConstantPool*)this)->print_entry_on(index, st);
1935 switch (tag_at(index).value()) {
1936 case JVM_CONSTANT_Long :
1937 case JVM_CONSTANT_Double :
1938 index++; // Skip entry following eigth-byte constant
1939 }
1941 }
1942 st->cr();
1943 }
1945 // Print one constant pool entry
1946 void ConstantPool::print_entry_on(const int index, outputStream* st) {
1947 EXCEPTION_MARK;
1948 st->print(" - %3d : ", index);
1949 tag_at(index).print_on(st);
1950 st->print(" : ");
1951 switch (tag_at(index).value()) {
1952 case JVM_CONSTANT_Class :
1953 { Klass* k = klass_at(index, CATCH);
1954 guarantee(k != NULL, "need klass");
1955 k->print_value_on(st);
1956 st->print(" {0x%lx}", (address)k);
1957 }
1958 break;
1959 case JVM_CONSTANT_Fieldref :
1960 case JVM_CONSTANT_Methodref :
1961 case JVM_CONSTANT_InterfaceMethodref :
1962 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
1963 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
1964 break;
1965 case JVM_CONSTANT_String :
1966 if (is_pseudo_string_at(index)) {
1967 oop anObj = pseudo_string_at(index);
1968 anObj->print_value_on(st);
1969 st->print(" {0x%lx}", (address)anObj);
1970 } else {
1971 unresolved_string_at(index)->print_value_on(st);
1972 }
1973 break;
1974 case JVM_CONSTANT_Integer :
1975 st->print("%d", int_at(index));
1976 break;
1977 case JVM_CONSTANT_Float :
1978 st->print("%f", float_at(index));
1979 break;
1980 case JVM_CONSTANT_Long :
1981 st->print_jlong(long_at(index));
1982 break;
1983 case JVM_CONSTANT_Double :
1984 st->print("%lf", double_at(index));
1985 break;
1986 case JVM_CONSTANT_NameAndType :
1987 st->print("name_index=%d", name_ref_index_at(index));
1988 st->print(" signature_index=%d", signature_ref_index_at(index));
1989 break;
1990 case JVM_CONSTANT_Utf8 :
1991 symbol_at(index)->print_value_on(st);
1992 break;
1993 case JVM_CONSTANT_UnresolvedClass : // fall-through
1994 case JVM_CONSTANT_UnresolvedClassInError: {
1995 // unresolved_klass_at requires lock or safe world.
1996 CPSlot entry = slot_at(index);
1997 if (entry.is_resolved()) {
1998 entry.get_klass()->print_value_on(st);
1999 } else {
2000 entry.get_symbol()->print_value_on(st);
2001 }
2002 }
2003 break;
2004 case JVM_CONSTANT_MethodHandle :
2005 case JVM_CONSTANT_MethodHandleInError :
2006 st->print("ref_kind=%d", method_handle_ref_kind_at_error_ok(index));
2007 st->print(" ref_index=%d", method_handle_index_at_error_ok(index));
2008 break;
2009 case JVM_CONSTANT_MethodType :
2010 case JVM_CONSTANT_MethodTypeInError :
2011 st->print("signature_index=%d", method_type_index_at_error_ok(index));
2012 break;
2013 case JVM_CONSTANT_InvokeDynamic :
2014 {
2015 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2016 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2017 int argc = invoke_dynamic_argument_count_at(index);
2018 if (argc > 0) {
2019 for (int arg_i = 0; arg_i < argc; arg_i++) {
2020 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2021 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2022 }
2023 st->print("}");
2024 }
2025 }
2026 break;
2027 default:
2028 ShouldNotReachHere();
2029 break;
2030 }
2031 st->cr();
2032 }
2034 void ConstantPool::print_value_on(outputStream* st) const {
2035 assert(is_constantPool(), "must be constantPool");
2036 st->print("constant pool [%d]", length());
2037 if (has_preresolution()) st->print("/preresolution");
2038 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2039 print_address_on(st);
2040 st->print(" for ");
2041 pool_holder()->print_value_on(st);
2042 if (pool_holder() != NULL) {
2043 bool extra = (pool_holder()->constants() != this);
2044 if (extra) st->print(" (extra)");
2045 }
2046 if (cache() != NULL) {
2047 st->print(" cache=" PTR_FORMAT, cache());
2048 }
2049 }
2051 #if INCLUDE_SERVICES
2052 // Size Statistics
2053 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2054 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2055 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2056 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2057 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2058 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2060 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2061 sz->_cp_refmap_bytes;
2062 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2063 }
2064 #endif // INCLUDE_SERVICES
2066 // Verification
2068 void ConstantPool::verify_on(outputStream* st) {
2069 guarantee(is_constantPool(), "object must be constant pool");
2070 for (int i = 0; i< length(); i++) {
2071 constantTag tag = tag_at(i);
2072 CPSlot entry = slot_at(i);
2073 if (tag.is_klass()) {
2074 if (entry.is_resolved()) {
2075 guarantee(entry.get_klass()->is_klass(), "should be klass");
2076 }
2077 } else if (tag.is_unresolved_klass()) {
2078 if (entry.is_resolved()) {
2079 guarantee(entry.get_klass()->is_klass(), "should be klass");
2080 }
2081 } else if (tag.is_symbol()) {
2082 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2083 } else if (tag.is_string()) {
2084 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2085 }
2086 }
2087 if (cache() != NULL) {
2088 // Note: cache() can be NULL before a class is completely setup or
2089 // in temporary constant pools used during constant pool merging
2090 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2091 }
2092 if (pool_holder() != NULL) {
2093 // Note: pool_holder() can be NULL in temporary constant pools
2094 // used during constant pool merging
2095 guarantee(pool_holder()->is_klass(), "should be klass");
2096 }
2097 }
2100 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2101 char *str = sym->as_utf8();
2102 unsigned int hash = compute_hash(str, sym->utf8_length());
2103 unsigned int index = hash % table_size();
2105 // check if already in map
2106 // we prefer the first entry since it is more likely to be what was used in
2107 // the class file
2108 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2109 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2110 if (en->hash() == hash && en->symbol() == sym) {
2111 return; // already there
2112 }
2113 }
2115 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2116 entry->set_next(bucket(index));
2117 _buckets[index].set_entry(entry);
2118 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2119 }
2121 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2122 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2123 char *str = sym->as_utf8();
2124 int len = sym->utf8_length();
2125 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2126 unsigned int index = hash % table_size();
2127 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2128 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2129 if (en->hash() == hash && en->symbol() == sym) {
2130 return en;
2131 }
2132 }
2133 return NULL;
2134 }