1 /*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoaderData.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/metadataOnStackMark.hpp"
29 #include "classfile/stringTable.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"
44
45 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
46
47 const char* ConstantPool::CPH_STR = "CONSTANT_PLACEHOLDER_";
48 const int ConstantPool::CPH_LEN = strlen(CPH_STR);
49
50 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
51 // Tags are RW but comment below applies to tags also.
52 Array<u1>* tags = MetadataFactory::new_writeable_array<u1>(loader_data, length, 0, CHECK_NULL);
53
54 int size = ConstantPool::size(length);
55
56 // CDS considerations:
57 // Allocate read-write but may be able to move to read-only at dumping time
58 // if all the klasses are resolved. The only other field that is writable is
59 // the resolved_references array, which is recreated at startup time.
60 // But that could be moved to InstanceKlass (although a pain to access from
61 // assembly code). Maybe it could be moved to the cpCache which is RW.
62 return new (loader_data, size, false, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
63 }
64
65 ConstantPool::ConstantPool(Array<u1>* tags) {
66 set_length(tags->length());
67 set_tags(NULL);
68 set_cache(NULL);
69 set_reference_map(NULL);
70 set_resolved_references(NULL);
71 set_operands(NULL);
72 set_pool_holder(NULL);
73 set_flags(0);
74
75 // only set to non-zero if constant pool is merged by RedefineClasses
76 set_version(0);
77
78 // initialize tag array
79 int length = tags->length();
80 for (int index = 0; index < length; index++) {
81 tags->at_put(index, JVM_CONSTANT_Invalid);
82 }
83 set_tags(tags);
84 }
85
86 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
87 MetadataFactory::free_metadata(loader_data, cache());
88 set_cache(NULL);
89 MetadataFactory::free_array<u2>(loader_data, reference_map());
90 set_reference_map(NULL);
91
92 MetadataFactory::free_array<jushort>(loader_data, operands());
93 set_operands(NULL);
94
95 release_C_heap_structures();
96
97 // free tag array
98 MetadataFactory::free_array<u1>(loader_data, tags());
99 set_tags(NULL);
100 }
101
102 void ConstantPool::release_C_heap_structures() {
103 // walk constant pool and decrement symbol reference counts
104 unreference_symbols();
105 }
106
107 objArrayOop ConstantPool::resolved_references() const {
108 return (objArrayOop)JNIHandles::resolve(_resolved_references);
109 }
110
111 // Create resolved_references array and mapping array for original cp indexes
112 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
113 // to map it back for resolving and some unlikely miscellaneous uses.
114 // The objects created by invokedynamic are appended to this list.
115 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
116 intStack reference_map,
117 int constant_pool_map_length,
118 TRAPS) {
119 // Initialized the resolved object cache.
120 int map_length = reference_map.length();
121 if (map_length > 0) {
122 // Only need mapping back to constant pool entries. The map isn't used for
123 // invokedynamic resolved_reference entries. For invokedynamic entries,
124 // the constant pool cache index has the mapping back to both the constant
125 // pool and to the resolved reference index.
126 if (constant_pool_map_length > 0) {
127 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
128
129 for (int i = 0; i < constant_pool_map_length; i++) {
130 int x = reference_map.at(i);
131 assert(x == (int)(jushort) x, "klass index is too big");
132 om->at_put(i, (jushort)x);
133 }
134 set_reference_map(om);
135 }
136
137 // Create Java array for holding resolved strings, methodHandles,
138 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
139 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
140 Handle refs_handle (THREAD, (oop)stom); // must handleize.
141 set_resolved_references(loader_data->add_handle(refs_handle));
142 }
143 }
144
145 // CDS support. Create a new resolved_references array.
146 void ConstantPool::restore_unshareable_info(TRAPS) {
147
148 // Only create the new resolved references array if it hasn't been attempted before
149 if (resolved_references() != NULL) return;
150
151 // restore the C++ vtable from the shared archive
152 restore_vtable();
153
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.
160
161 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
162 set_resolved_references(loader_data->add_handle(refs_handle));
163 }
164 }
165 }
166
167 void ConstantPool::remove_unshareable_info() {
168 // Resolved references are not in the shared archive.
169 // Save the length for restoration. It is not necessarily the same length
170 // as reference_map.length() if invokedynamic is saved.
171 set_resolved_reference_length(
172 resolved_references() != NULL ? resolved_references()->length() : 0);
173 set_resolved_references(NULL);
174 }
175
176 int ConstantPool::cp_to_object_index(int cp_index) {
177 // this is harder don't do this so much.
178 int i = reference_map()->find(cp_index);
179 // We might not find the index for jsr292 call.
180 return (i < 0) ? _no_index_sentinel : i;
181 }
182
183 void ConstantPool::trace_class_resolution(constantPoolHandle this_cp, KlassHandle k) {
184 ResourceMark rm;
185 int line_number = -1;
186 const char * source_file = NULL;
187 if (JavaThread::current()->has_last_Java_frame()) {
188 // try to identify the method which called this function.
189 vframeStream vfst(JavaThread::current());
190 if (!vfst.at_end()) {
191 line_number = vfst.method()->line_number_from_bci(vfst.bci());
192 Symbol* s = vfst.method()->method_holder()->source_file_name();
193 if (s != NULL) {
194 source_file = s->as_C_string();
195 }
196 }
197 }
198 if (k() != this_cp->pool_holder()) {
199 // only print something if the classes are different
200 if (source_file != NULL) {
201 tty->print("RESOLVE %s %s %s:%d\n",
202 this_cp->pool_holder()->external_name(),
203 InstanceKlass::cast(k())->external_name(), source_file, line_number);
204 } else {
205 tty->print("RESOLVE %s %s\n",
206 this_cp->pool_holder()->external_name(),
207 InstanceKlass::cast(k())->external_name());
208 }
209 }
210 }
211
212 Klass* ConstantPool::klass_at_impl(constantPoolHandle this_cp, int which,
213 bool save_resolution_error, TRAPS) {
214 assert(THREAD->is_Java_thread(), "must be a Java thread");
215
216 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
217 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
218 // the entry and tag is not updated atomicly.
219 CPSlot entry = this_cp->slot_at(which);
220 if (entry.is_resolved()) {
221 assert(entry.get_klass()->is_klass(), "must be");
222 // Already resolved - return entry.
223 return entry.get_klass();
224 }
225
226 // This tag doesn't change back to unresolved class unless at a safepoint.
227 if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
228 // The original attempt to resolve this constant pool entry failed so find the
229 // class of the original error and throw another error of the same class
230 // (JVMS 5.4.3).
231 // If there is a detail message, pass that detail message to the error.
232 // The JVMS does not strictly require us to duplicate the same detail message,
233 // or any internal exception fields such as cause or stacktrace. But since the
234 // detail message is often a class name or other literal string, we will repeat it
235 // if we can find it in the symbol table.
236 throw_resolution_error(this_cp, which, CHECK_0);
237 ShouldNotReachHere();
238 }
239
240 Handle mirror_handle;
241 Symbol* name = entry.get_symbol();
242 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
243 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
244 Klass* kk = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
245 KlassHandle k (THREAD, kk);
246 if (!HAS_PENDING_EXCEPTION) {
247 // preserve the resolved klass from unloading
248 mirror_handle = Handle(THREAD, kk->java_mirror());
249 // Do access check for klasses
250 verify_constant_pool_resolve(this_cp, k, THREAD);
251 }
252
253 // Failed to resolve class. We must record the errors so that subsequent attempts
254 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
255 if (HAS_PENDING_EXCEPTION) {
256 if (save_resolution_error) {
257 save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
258 // If CHECK_NULL above doesn't return the exception, that means that
259 // some other thread has beaten us and has resolved the class.
260 // To preserve old behavior, we return the resolved class.
261 entry = this_cp->resolved_klass_at(which);
262 assert(entry.is_resolved(), "must be resolved if exception was cleared");
263 assert(entry.get_klass()->is_klass(), "must be resolved to a klass");
264 return entry.get_klass();
265 } else {
266 return NULL; // return the pending exception
267 }
268 }
269
270 // Make this class loader depend upon the class loader owning the class reference
271 ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
272 this_key->record_dependency(k(), CHECK_NULL); // Can throw OOM
273
274 if (TraceClassResolution && !k->oop_is_array()) {
275 // skip resolving the constant pool so that this code gets
276 // called the next time some bytecodes refer to this class.
277 trace_class_resolution(this_cp, k);
278 return k();
279 } else {
280 this_cp->klass_at_put(which, k());
281 }
282
283 entry = this_cp->resolved_klass_at(which);
284 assert(entry.is_resolved() && entry.get_klass()->is_klass(), "must be resolved at this point");
285 return entry.get_klass();
286 }
287
288
289 // Does not update ConstantPool* - to avoid any exception throwing. Used
290 // by compiler and exception handling. Also used to avoid classloads for
291 // instanceof operations. Returns NULL if the class has not been loaded or
292 // if the verification of constant pool failed
293 Klass* ConstantPool::klass_at_if_loaded(constantPoolHandle this_cp, int which) {
294 CPSlot entry = this_cp->slot_at(which);
295 if (entry.is_resolved()) {
296 assert(entry.get_klass()->is_klass(), "must be");
297 return entry.get_klass();
298 } else {
299 assert(entry.is_unresolved(), "must be either symbol or klass");
300 Thread *thread = Thread::current();
301 Symbol* name = entry.get_symbol();
302 oop loader = this_cp->pool_holder()->class_loader();
303 oop protection_domain = this_cp->pool_holder()->protection_domain();
304 Handle h_prot (thread, protection_domain);
305 Handle h_loader (thread, loader);
306 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
307
308 if (k != NULL) {
309 // Make sure that resolving is legal
310 EXCEPTION_MARK;
311 KlassHandle klass(THREAD, k);
312 // return NULL if verification fails
313 verify_constant_pool_resolve(this_cp, klass, THREAD);
314 if (HAS_PENDING_EXCEPTION) {
315 CLEAR_PENDING_EXCEPTION;
316 return NULL;
317 }
318 return klass();
319 } else {
320 return k;
321 }
322 }
323 }
324
325
326 Klass* ConstantPool::klass_ref_at_if_loaded(constantPoolHandle this_cp, int which) {
327 return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
328 }
329
330
331 Method* ConstantPool::method_at_if_loaded(constantPoolHandle cpool,
332 int which) {
333 if (cpool->cache() == NULL) return NULL; // nothing to load yet
334 int cache_index = decode_cpcache_index(which, true);
335 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
336 // FIXME: should be an assert
337 if (PrintMiscellaneous && (Verbose||WizardMode)) {
338 tty->print_cr("bad operand %d in:", which); cpool->print();
339 }
340 return NULL;
341 }
342 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
343 return e->method_if_resolved(cpool);
344 }
345
346
347 bool ConstantPool::has_appendix_at_if_loaded(constantPoolHandle cpool, int which) {
348 if (cpool->cache() == NULL) return false; // nothing to load yet
349 int cache_index = decode_cpcache_index(which, true);
350 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
351 return e->has_appendix();
352 }
353
354 oop ConstantPool::appendix_at_if_loaded(constantPoolHandle cpool, int which) {
355 if (cpool->cache() == NULL) return NULL; // nothing to load yet
356 int cache_index = decode_cpcache_index(which, true);
357 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
358 return e->appendix_if_resolved(cpool);
359 }
360
361
362 bool ConstantPool::has_method_type_at_if_loaded(constantPoolHandle cpool, int which) {
363 if (cpool->cache() == NULL) return false; // nothing to load yet
364 int cache_index = decode_cpcache_index(which, true);
365 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
366 return e->has_method_type();
367 }
368
369 oop ConstantPool::method_type_at_if_loaded(constantPoolHandle cpool, int which) {
370 if (cpool->cache() == NULL) return NULL; // nothing to load yet
371 int cache_index = decode_cpcache_index(which, true);
372 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
373 return e->method_type_if_resolved(cpool);
374 }
375
376
377 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
378 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
379 return symbol_at(name_index);
380 }
381
382
383 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
384 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
385 return symbol_at(signature_index);
386 }
387
388
389 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
390 int i = which;
391 if (!uncached && cache() != NULL) {
392 if (ConstantPool::is_invokedynamic_index(which)) {
393 // Invokedynamic index is index into resolved_references
394 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
395 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
396 assert(tag_at(pool_index).is_name_and_type(), "");
397 return pool_index;
398 }
399 // change byte-ordering and go via cache
400 i = remap_instruction_operand_from_cache(which);
401 } else {
402 if (tag_at(which).is_invoke_dynamic()) {
403 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
404 assert(tag_at(pool_index).is_name_and_type(), "");
405 return pool_index;
406 }
407 }
408 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
409 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
410 jint ref_index = *int_at_addr(i);
411 return extract_high_short_from_int(ref_index);
412 }
413
414
415 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
416 guarantee(!ConstantPool::is_invokedynamic_index(which),
417 "an invokedynamic instruction does not have a klass");
418 int i = which;
419 if (!uncached && cache() != NULL) {
420 // change byte-ordering and go via cache
421 i = remap_instruction_operand_from_cache(which);
422 }
423 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
424 jint ref_index = *int_at_addr(i);
425 return extract_low_short_from_int(ref_index);
426 }
427
428
429
430 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
431 int cpc_index = operand;
432 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
433 assert((int)(u2)cpc_index == cpc_index, "clean u2");
434 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
435 return member_index;
436 }
437
438
439 void ConstantPool::verify_constant_pool_resolve(constantPoolHandle this_cp, KlassHandle k, TRAPS) {
440 if (k->oop_is_instance() || k->oop_is_objArray()) {
441 instanceKlassHandle holder (THREAD, this_cp->pool_holder());
442 Klass* elem = k->oop_is_instance() ? k() : ObjArrayKlass::cast(k())->bottom_klass();
443 KlassHandle element (THREAD, elem);
444
445 // The element type could be a typeArray - we only need the access check if it is
446 // an reference to another class
447 if (element->oop_is_instance()) {
448 LinkResolver::check_klass_accessability(holder, element, CHECK);
449 }
450 }
451 }
452
453
454 int ConstantPool::name_ref_index_at(int which_nt) {
455 jint ref_index = name_and_type_at(which_nt);
456 return extract_low_short_from_int(ref_index);
457 }
458
459
460 int ConstantPool::signature_ref_index_at(int which_nt) {
461 jint ref_index = name_and_type_at(which_nt);
462 return extract_high_short_from_int(ref_index);
463 }
464
465
466 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
467 return klass_at(klass_ref_index_at(which), THREAD);
468 }
469
470
471 Symbol* ConstantPool::klass_name_at(int which) {
472 assert(tag_at(which).is_unresolved_klass() || tag_at(which).is_klass(),
473 "Corrupted constant pool");
474 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
475 // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
476 // tag is not updated atomicly.
477 CPSlot entry = slot_at(which);
478 if (entry.is_resolved()) {
479 // Already resolved - return entry's name.
480 assert(entry.get_klass()->is_klass(), "must be");
481 return entry.get_klass()->name();
482 } else {
483 assert(entry.is_unresolved(), "must be either symbol or klass");
484 return entry.get_symbol();
485 }
486 }
487
488 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
489 jint ref_index = klass_ref_index_at(which);
490 return klass_at_noresolve(ref_index);
491 }
492
493 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
494 jint ref_index = uncached_klass_ref_index_at(which);
495 return klass_at_noresolve(ref_index);
496 }
497
498 char* ConstantPool::string_at_noresolve(int which) {
499 Symbol* s = unresolved_string_at(which);
500 if (s == NULL) {
501 return (char*)"<pseudo-string>";
502 } else {
503 return unresolved_string_at(which)->as_C_string();
504 }
505 }
506
507 BasicType ConstantPool::basic_type_for_signature_at(int which) {
508 return FieldType::basic_type(symbol_at(which));
509 }
510
511
512 void ConstantPool::resolve_string_constants_impl(constantPoolHandle this_cp, TRAPS) {
513 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
514 if (this_cp->tag_at(index).is_string()) {
515 this_cp->string_at(index, CHECK);
516 }
517 }
518 }
519
520 // Resolve all the classes in the constant pool. If they are all resolved,
521 // the constant pool is read-only. Enhancement: allocate cp entries to
522 // another metaspace, and copy to read-only or read-write space if this
523 // bit is set.
524 bool ConstantPool::resolve_class_constants(TRAPS) {
525 constantPoolHandle cp(THREAD, this);
526 for (int index = 1; index < length(); index++) { // Index 0 is unused
527 if (tag_at(index).is_unresolved_klass() &&
528 klass_at_if_loaded(cp, index) == NULL) {
529 return false;
530 }
531 }
532 // set_preresolution(); or some bit for future use
533 return true;
534 }
535
536 Symbol* ConstantPool::exception_message(constantPoolHandle this_cp, int which, constantTag tag, oop pending_exception) {
537 // Dig out the detailed message to reuse if possible
538 Symbol* message = java_lang_Throwable::detail_message(pending_exception);
539 if (message != NULL) {
540 return message;
541 }
542
543 // Return specific message for the tag
544 switch (tag.value()) {
545 case JVM_CONSTANT_UnresolvedClass:
546 // return the class name in the error message
547 message = this_cp->klass_name_at(which);
548 break;
549 case JVM_CONSTANT_MethodHandle:
550 // return the method handle name in the error message
551 message = this_cp->method_handle_name_ref_at(which);
552 break;
553 case JVM_CONSTANT_MethodType:
554 // return the method type signature in the error message
555 message = this_cp->method_type_signature_at(which);
556 break;
557 default:
558 ShouldNotReachHere();
559 }
560
561 return message;
562 }
563
564 void ConstantPool::throw_resolution_error(constantPoolHandle this_cp, int which, TRAPS) {
565 Symbol* message = NULL;
566 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
567 assert(error != NULL && message != NULL, "checking");
568 CLEAR_PENDING_EXCEPTION;
569 ResourceMark rm;
570 THROW_MSG(error, message->as_C_string());
571 }
572
573 // If resolution for Class, MethodHandle or MethodType fails, save the exception
574 // in the resolution error table, so that the same exception is thrown again.
575 void ConstantPool::save_and_throw_exception(constantPoolHandle this_cp, int which,
576 constantTag tag, TRAPS) {
577 Symbol* error = PENDING_EXCEPTION->klass()->name();
578
579 int error_tag = tag.error_value();
580
581 if (!PENDING_EXCEPTION->
582 is_a(SystemDictionary::LinkageError_klass())) {
583 // Just throw the exception and don't prevent these classes from
584 // being loaded due to virtual machine errors like StackOverflow
585 // and OutOfMemoryError, etc, or if the thread was hit by stop()
586 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
587 } else if (this_cp->tag_at(which).value() != error_tag) {
588 Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
589 SystemDictionary::add_resolution_error(this_cp, which, error, message);
590 // CAS in the tag. If a thread beat us to registering this error that's fine.
591 // If another thread resolved the reference, this is a race condition. This
592 // thread may have had a security manager or something temporary.
593 // This doesn't deterministically get an error. So why do we save this?
594 // We save this because jvmti can add classes to the bootclass path after
595 // this error, so it needs to get the same error if the error is first.
596 jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
597 (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
598 if (old_tag != error_tag && old_tag != tag.value()) {
599 // MethodHandles and MethodType doesn't change to resolved version.
600 assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
601 // Forget the exception and use the resolved class.
602 CLEAR_PENDING_EXCEPTION;
603 }
604 } else {
605 // some other thread put this in error state
606 throw_resolution_error(this_cp, which, CHECK);
607 }
608 }
609
610 // Called to resolve constants in the constant pool and return an oop.
611 // Some constant pool entries cache their resolved oop. This is also
612 // called to create oops from constants to use in arguments for invokedynamic
613 oop ConstantPool::resolve_constant_at_impl(constantPoolHandle this_cp, int index, int cache_index, TRAPS) {
614 oop result_oop = NULL;
615 Handle throw_exception;
616
617 if (cache_index == _possible_index_sentinel) {
618 // It is possible that this constant is one which is cached in the objects.
619 // We'll do a linear search. This should be OK because this usage is rare.
620 assert(index > 0, "valid index");
621 cache_index = this_cp->cp_to_object_index(index);
622 }
623 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
624 assert(index == _no_index_sentinel || index >= 0, "");
625
626 if (cache_index >= 0) {
627 result_oop = this_cp->resolved_references()->obj_at(cache_index);
628 if (result_oop != NULL) {
629 return result_oop;
630 // That was easy...
631 }
632 index = this_cp->object_to_cp_index(cache_index);
633 }
634
635 jvalue prim_value; // temp used only in a few cases below
636
637 constantTag tag = this_cp->tag_at(index);
638
639 switch (tag.value()) {
640
641 case JVM_CONSTANT_UnresolvedClass:
642 case JVM_CONSTANT_UnresolvedClassInError:
643 case JVM_CONSTANT_Class:
644 {
645 assert(cache_index == _no_index_sentinel, "should not have been set");
646 Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
647 // ldc wants the java mirror.
648 result_oop = resolved->java_mirror();
649 break;
650 }
651
652 case JVM_CONSTANT_String:
653 assert(cache_index != _no_index_sentinel, "should have been set");
654 if (this_cp->is_pseudo_string_at(index)) {
655 result_oop = this_cp->pseudo_string_at(index, cache_index);
656 break;
657 }
658 result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
659 break;
660
661 case JVM_CONSTANT_MethodHandleInError:
662 case JVM_CONSTANT_MethodTypeInError:
663 {
664 throw_resolution_error(this_cp, index, CHECK_NULL);
665 break;
666 }
667
668 case JVM_CONSTANT_MethodHandle:
669 {
670 int ref_kind = this_cp->method_handle_ref_kind_at(index);
671 int callee_index = this_cp->method_handle_klass_index_at(index);
672 Symbol* name = this_cp->method_handle_name_ref_at(index);
673 Symbol* signature = this_cp->method_handle_signature_ref_at(index);
674 if (PrintMiscellaneous)
675 tty->print_cr("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
676 ref_kind, index, this_cp->method_handle_index_at(index),
677 callee_index, name->as_C_string(), signature->as_C_string());
678 KlassHandle callee;
679 { Klass* k = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
680 callee = KlassHandle(THREAD, k);
681 }
682 KlassHandle klass(THREAD, this_cp->pool_holder());
683 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
684 callee, name, signature,
685 THREAD);
686 result_oop = value();
687 if (HAS_PENDING_EXCEPTION) {
688 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
689 }
690 break;
691 }
692
693 case JVM_CONSTANT_MethodType:
694 {
695 Symbol* signature = this_cp->method_type_signature_at(index);
696 if (PrintMiscellaneous)
697 tty->print_cr("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
698 index, this_cp->method_type_index_at(index),
699 signature->as_C_string());
700 KlassHandle klass(THREAD, this_cp->pool_holder());
701 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
702 result_oop = value();
703 if (HAS_PENDING_EXCEPTION) {
704 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
705 }
706 break;
707 }
708
709 case JVM_CONSTANT_Integer:
710 assert(cache_index == _no_index_sentinel, "should not have been set");
711 prim_value.i = this_cp->int_at(index);
712 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
713 break;
714
715 case JVM_CONSTANT_Float:
716 assert(cache_index == _no_index_sentinel, "should not have been set");
717 prim_value.f = this_cp->float_at(index);
718 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
719 break;
720
721 case JVM_CONSTANT_Long:
722 assert(cache_index == _no_index_sentinel, "should not have been set");
723 prim_value.j = this_cp->long_at(index);
724 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
725 break;
726
727 case JVM_CONSTANT_Double:
728 assert(cache_index == _no_index_sentinel, "should not have been set");
729 prim_value.d = this_cp->double_at(index);
730 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
731 break;
732
733 default:
734 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
735 this_cp(), index, cache_index, tag.value()));
736 assert(false, "unexpected constant tag");
737 break;
738 }
739
740 if (cache_index >= 0) {
741 // Benign race condition: resolved_references may already be filled in.
742 // The important thing here is that all threads pick up the same result.
743 // It doesn't matter which racing thread wins, as long as only one
744 // result is used by all threads, and all future queries.
745 oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
746 if (old_result == NULL) {
747 return result_oop; // was installed
748 } else {
749 // Return the winning thread's result. This can be different than
750 // the result here for MethodHandles.
751 return old_result;
752 }
753 } else {
754 return result_oop;
755 }
756 }
757
758 oop ConstantPool::uncached_string_at(int which, TRAPS) {
759 Symbol* sym = unresolved_string_at(which);
760 oop str = StringTable::intern(sym, CHECK_(NULL));
761 assert(java_lang_String::is_instance(str), "must be string");
762 return str;
763 }
764
765
766 oop ConstantPool::resolve_bootstrap_specifier_at_impl(constantPoolHandle this_cp, int index, TRAPS) {
767 assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
768
769 Handle bsm;
770 int argc;
771 {
772 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
773 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
774 // It is accompanied by the optional arguments.
775 int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
776 oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
777 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
778 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
779 }
780
781 // Extract the optional static arguments.
782 argc = this_cp->invoke_dynamic_argument_count_at(index);
783 if (argc == 0) return bsm_oop;
784
785 bsm = Handle(THREAD, bsm_oop);
786 }
787
788 objArrayHandle info;
789 {
790 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
791 info = objArrayHandle(THREAD, info_oop);
792 }
793
794 info->obj_at_put(0, bsm());
795 for (int i = 0; i < argc; i++) {
796 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
797 oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
798 info->obj_at_put(1+i, arg_oop);
799 }
800
801 return info();
802 }
803
804 oop ConstantPool::string_at_impl(constantPoolHandle this_cp, int which, int obj_index, TRAPS) {
805 // If the string has already been interned, this entry will be non-null
806 oop str = this_cp->resolved_references()->obj_at(obj_index);
807 if (str != NULL) return str;
808 Symbol* sym = this_cp->unresolved_string_at(which);
809 str = StringTable::intern(sym, CHECK_(NULL));
810 this_cp->string_at_put(which, obj_index, str);
811 assert(java_lang_String::is_instance(str), "must be string");
812 return str;
813 }
814
815
816 bool ConstantPool::klass_name_at_matches(instanceKlassHandle k,
817 int which) {
818 // Names are interned, so we can compare Symbol*s directly
819 Symbol* cp_name = klass_name_at(which);
820 return (cp_name == k->name());
821 }
822
823
824 // Iterate over symbols and decrement ones which are Symbol*s
825 // This is done during GC.
826 // Only decrement the UTF8 symbols. Unresolved classes and strings point to
827 // these symbols but didn't increment the reference count.
828 void ConstantPool::unreference_symbols() {
829 for (int index = 1; index < length(); index++) { // Index 0 is unused
830 constantTag tag = tag_at(index);
831 if (tag.is_symbol()) {
832 symbol_at(index)->decrement_refcount();
833 }
834 }
835 }
836
837
838 // Compare this constant pool's entry at index1 to the constant pool
839 // cp2's entry at index2.
840 bool ConstantPool::compare_entry_to(int index1, constantPoolHandle cp2,
841 int index2, TRAPS) {
842
843 // The error tags are equivalent to non-error tags when comparing
844 jbyte t1 = tag_at(index1).non_error_value();
845 jbyte t2 = cp2->tag_at(index2).non_error_value();
846
847 if (t1 != t2) {
848 // Not the same entry type so there is nothing else to check. Note
849 // that this style of checking will consider resolved/unresolved
850 // class pairs as different.
851 // From the ConstantPool* API point of view, this is correct
852 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
853 // plays out in the context of ConstantPool* merging.
854 return false;
855 }
856
857 switch (t1) {
858 case JVM_CONSTANT_Class:
859 {
860 Klass* k1 = klass_at(index1, CHECK_false);
861 Klass* k2 = cp2->klass_at(index2, CHECK_false);
862 if (k1 == k2) {
863 return true;
864 }
865 } break;
866
867 case JVM_CONSTANT_ClassIndex:
868 {
869 int recur1 = klass_index_at(index1);
870 int recur2 = cp2->klass_index_at(index2);
871 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
872 if (match) {
873 return true;
874 }
875 } break;
876
877 case JVM_CONSTANT_Double:
878 {
879 jdouble d1 = double_at(index1);
880 jdouble d2 = cp2->double_at(index2);
881 if (d1 == d2) {
882 return true;
883 }
884 } break;
885
886 case JVM_CONSTANT_Fieldref:
887 case JVM_CONSTANT_InterfaceMethodref:
888 case JVM_CONSTANT_Methodref:
889 {
890 int recur1 = uncached_klass_ref_index_at(index1);
891 int recur2 = cp2->uncached_klass_ref_index_at(index2);
892 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
893 if (match) {
894 recur1 = uncached_name_and_type_ref_index_at(index1);
895 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
896 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
897 if (match) {
898 return true;
899 }
900 }
901 } break;
902
903 case JVM_CONSTANT_Float:
904 {
905 jfloat f1 = float_at(index1);
906 jfloat f2 = cp2->float_at(index2);
907 if (f1 == f2) {
908 return true;
909 }
910 } break;
911
912 case JVM_CONSTANT_Integer:
913 {
914 jint i1 = int_at(index1);
915 jint i2 = cp2->int_at(index2);
916 if (i1 == i2) {
917 return true;
918 }
919 } break;
920
921 case JVM_CONSTANT_Long:
922 {
923 jlong l1 = long_at(index1);
924 jlong l2 = cp2->long_at(index2);
925 if (l1 == l2) {
926 return true;
927 }
928 } break;
929
930 case JVM_CONSTANT_NameAndType:
931 {
932 int recur1 = name_ref_index_at(index1);
933 int recur2 = cp2->name_ref_index_at(index2);
934 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
935 if (match) {
936 recur1 = signature_ref_index_at(index1);
937 recur2 = cp2->signature_ref_index_at(index2);
938 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
939 if (match) {
940 return true;
941 }
942 }
943 } break;
944
945 case JVM_CONSTANT_StringIndex:
946 {
947 int recur1 = string_index_at(index1);
948 int recur2 = cp2->string_index_at(index2);
949 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
950 if (match) {
951 return true;
952 }
953 } break;
954
955 case JVM_CONSTANT_UnresolvedClass:
956 {
957 Symbol* k1 = klass_name_at(index1);
958 Symbol* k2 = cp2->klass_name_at(index2);
959 if (k1 == k2) {
960 return true;
961 }
962 } break;
963
964 case JVM_CONSTANT_MethodType:
965 {
966 int k1 = method_type_index_at_error_ok(index1);
967 int k2 = cp2->method_type_index_at_error_ok(index2);
968 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
969 if (match) {
970 return true;
971 }
972 } break;
973
974 case JVM_CONSTANT_MethodHandle:
975 {
976 int k1 = method_handle_ref_kind_at_error_ok(index1);
977 int k2 = cp2->method_handle_ref_kind_at_error_ok(index2);
978 if (k1 == k2) {
979 int i1 = method_handle_index_at_error_ok(index1);
980 int i2 = cp2->method_handle_index_at_error_ok(index2);
981 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
982 if (match) {
983 return true;
984 }
985 }
986 } break;
987
988 case JVM_CONSTANT_InvokeDynamic:
989 {
990 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
991 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
992 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
993 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
994 // separate statements and variables because CHECK_false is used
995 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
996 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
997 return (match_entry && match_operand);
998 } break;
999
1000 case JVM_CONSTANT_String:
1001 {
1002 Symbol* s1 = unresolved_string_at(index1);
1003 Symbol* s2 = cp2->unresolved_string_at(index2);
1004 if (s1 == s2) {
1005 return true;
1006 }
1007 } break;
1008
1009 case JVM_CONSTANT_Utf8:
1010 {
1011 Symbol* s1 = symbol_at(index1);
1012 Symbol* s2 = cp2->symbol_at(index2);
1013 if (s1 == s2) {
1014 return true;
1015 }
1016 } break;
1017
1018 // Invalid is used as the tag for the second constant pool entry
1019 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1020 // not be seen by itself.
1021 case JVM_CONSTANT_Invalid: // fall through
1022
1023 default:
1024 ShouldNotReachHere();
1025 break;
1026 }
1027
1028 return false;
1029 } // end compare_entry_to()
1030
1031
1032 // Resize the operands array with delta_len and delta_size.
1033 // Used in RedefineClasses for CP merge.
1034 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1035 int old_len = operand_array_length(operands());
1036 int new_len = old_len + delta_len;
1037 int min_len = (delta_len > 0) ? old_len : new_len;
1038
1039 int old_size = operands()->length();
1040 int new_size = old_size + delta_size;
1041 int min_size = (delta_size > 0) ? old_size : new_size;
1042
1043 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1044 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1045
1046 // Set index in the resized array for existing elements only
1047 for (int idx = 0; idx < min_len; idx++) {
1048 int offset = operand_offset_at(idx); // offset in original array
1049 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1050 }
1051 // Copy the bootstrap specifiers only
1052 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1053 new_ops->adr_at(2*new_len),
1054 (min_size - 2*min_len) * sizeof(u2));
1055 // Explicitly deallocate old operands array.
1056 // Note, it is not needed for 7u backport.
1057 if ( operands() != NULL) { // the safety check
1058 MetadataFactory::free_array<u2>(loader_data, operands());
1059 }
1060 set_operands(new_ops);
1061 } // end resize_operands()
1062
1063
1064 // Extend the operands array with the length and size of the ext_cp operands.
1065 // Used in RedefineClasses for CP merge.
1066 void ConstantPool::extend_operands(constantPoolHandle ext_cp, TRAPS) {
1067 int delta_len = operand_array_length(ext_cp->operands());
1068 if (delta_len == 0) {
1069 return; // nothing to do
1070 }
1071 int delta_size = ext_cp->operands()->length();
1072
1073 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1074
1075 if (operand_array_length(operands()) == 0) {
1076 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1077 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1078 // The first element index defines the offset of second part
1079 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1080 set_operands(new_ops);
1081 } else {
1082 resize_operands(delta_len, delta_size, CHECK);
1083 }
1084
1085 } // end extend_operands()
1086
1087
1088 // Shrink the operands array to a smaller array with new_len length.
1089 // Used in RedefineClasses for CP merge.
1090 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1091 int old_len = operand_array_length(operands());
1092 if (new_len == old_len) {
1093 return; // nothing to do
1094 }
1095 assert(new_len < old_len, "shrunken operands array must be smaller");
1096
1097 int free_base = operand_next_offset_at(new_len - 1);
1098 int delta_len = new_len - old_len;
1099 int delta_size = 2*delta_len + free_base - operands()->length();
1100
1101 resize_operands(delta_len, delta_size, CHECK);
1102
1103 } // end shrink_operands()
1104
1105
1106 void ConstantPool::copy_operands(constantPoolHandle from_cp,
1107 constantPoolHandle to_cp,
1108 TRAPS) {
1109
1110 int from_oplen = operand_array_length(from_cp->operands());
1111 int old_oplen = operand_array_length(to_cp->operands());
1112 if (from_oplen != 0) {
1113 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1114 // append my operands to the target's operands array
1115 if (old_oplen == 0) {
1116 // Can't just reuse from_cp's operand list because of deallocation issues
1117 int len = from_cp->operands()->length();
1118 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1119 Copy::conjoint_memory_atomic(
1120 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1121 to_cp->set_operands(new_ops);
1122 } else {
1123 int old_len = to_cp->operands()->length();
1124 int from_len = from_cp->operands()->length();
1125 int old_off = old_oplen * sizeof(u2);
1126 int from_off = from_oplen * sizeof(u2);
1127 // Use the metaspace for the destination constant pool
1128 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1129 int fillp = 0, len = 0;
1130 // first part of dest
1131 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1132 new_operands->adr_at(fillp),
1133 (len = old_off) * sizeof(u2));
1134 fillp += len;
1135 // first part of src
1136 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1137 new_operands->adr_at(fillp),
1138 (len = from_off) * sizeof(u2));
1139 fillp += len;
1140 // second part of dest
1141 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1142 new_operands->adr_at(fillp),
1143 (len = old_len - old_off) * sizeof(u2));
1144 fillp += len;
1145 // second part of src
1146 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1147 new_operands->adr_at(fillp),
1148 (len = from_len - from_off) * sizeof(u2));
1149 fillp += len;
1150 assert(fillp == new_operands->length(), "");
1151
1152 // Adjust indexes in the first part of the copied operands array.
1153 for (int j = 0; j < from_oplen; j++) {
1154 int offset = operand_offset_at(new_operands, old_oplen + j);
1155 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1156 offset += old_len; // every new tuple is preceded by old_len extra u2's
1157 operand_offset_at_put(new_operands, old_oplen + j, offset);
1158 }
1159
1160 // replace target operands array with combined array
1161 to_cp->set_operands(new_operands);
1162 }
1163 }
1164 } // end copy_operands()
1165
1166
1167 // Copy this constant pool's entries at start_i to end_i (inclusive)
1168 // to the constant pool to_cp's entries starting at to_i. A total of
1169 // (end_i - start_i) + 1 entries are copied.
1170 void ConstantPool::copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i,
1171 constantPoolHandle to_cp, int to_i, TRAPS) {
1172
1173
1174 int dest_i = to_i; // leave original alone for debug purposes
1175
1176 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1177 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1178
1179 switch (from_cp->tag_at(src_i).value()) {
1180 case JVM_CONSTANT_Double:
1181 case JVM_CONSTANT_Long:
1182 // double and long take two constant pool entries
1183 src_i += 2;
1184 dest_i += 2;
1185 break;
1186
1187 default:
1188 // all others take one constant pool entry
1189 src_i++;
1190 dest_i++;
1191 break;
1192 }
1193 }
1194 copy_operands(from_cp, to_cp, CHECK);
1195
1196 } // end copy_cp_to_impl()
1197
1198
1199 // Copy this constant pool's entry at from_i to the constant pool
1200 // to_cp's entry at to_i.
1201 void ConstantPool::copy_entry_to(constantPoolHandle from_cp, int from_i,
1202 constantPoolHandle to_cp, int to_i,
1203 TRAPS) {
1204
1205 int tag = from_cp->tag_at(from_i).value();
1206 switch (tag) {
1207 case JVM_CONSTANT_Class:
1208 {
1209 Klass* k = from_cp->klass_at(from_i, CHECK);
1210 to_cp->klass_at_put(to_i, k);
1211 } break;
1212
1213 case JVM_CONSTANT_ClassIndex:
1214 {
1215 jint ki = from_cp->klass_index_at(from_i);
1216 to_cp->klass_index_at_put(to_i, ki);
1217 } break;
1218
1219 case JVM_CONSTANT_Double:
1220 {
1221 jdouble d = from_cp->double_at(from_i);
1222 to_cp->double_at_put(to_i, d);
1223 // double takes two constant pool entries so init second entry's tag
1224 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1225 } break;
1226
1227 case JVM_CONSTANT_Fieldref:
1228 {
1229 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1230 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1231 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1232 } break;
1233
1234 case JVM_CONSTANT_Float:
1235 {
1236 jfloat f = from_cp->float_at(from_i);
1237 to_cp->float_at_put(to_i, f);
1238 } break;
1239
1240 case JVM_CONSTANT_Integer:
1241 {
1242 jint i = from_cp->int_at(from_i);
1243 to_cp->int_at_put(to_i, i);
1244 } break;
1245
1246 case JVM_CONSTANT_InterfaceMethodref:
1247 {
1248 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1249 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1250 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1251 } break;
1252
1253 case JVM_CONSTANT_Long:
1254 {
1255 jlong l = from_cp->long_at(from_i);
1256 to_cp->long_at_put(to_i, l);
1257 // long takes two constant pool entries so init second entry's tag
1258 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1259 } break;
1260
1261 case JVM_CONSTANT_Methodref:
1262 {
1263 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1264 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1265 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1266 } break;
1267
1268 case JVM_CONSTANT_NameAndType:
1269 {
1270 int name_ref_index = from_cp->name_ref_index_at(from_i);
1271 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1272 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1273 } break;
1274
1275 case JVM_CONSTANT_StringIndex:
1276 {
1277 jint si = from_cp->string_index_at(from_i);
1278 to_cp->string_index_at_put(to_i, si);
1279 } break;
1280
1281 case JVM_CONSTANT_UnresolvedClass:
1282 case JVM_CONSTANT_UnresolvedClassInError:
1283 {
1284 // Can be resolved after checking tag, so check the slot first.
1285 CPSlot entry = from_cp->slot_at(from_i);
1286 if (entry.is_resolved()) {
1287 assert(entry.get_klass()->is_klass(), "must be");
1288 // Already resolved
1289 to_cp->klass_at_put(to_i, entry.get_klass());
1290 } else {
1291 to_cp->unresolved_klass_at_put(to_i, entry.get_symbol());
1292 }
1293 } break;
1294
1295 case JVM_CONSTANT_String:
1296 {
1297 Symbol* s = from_cp->unresolved_string_at(from_i);
1298 to_cp->unresolved_string_at_put(to_i, s);
1299 } break;
1300
1301 case JVM_CONSTANT_Utf8:
1302 {
1303 Symbol* s = from_cp->symbol_at(from_i);
1304 // Need to increase refcount, the old one will be thrown away and deferenced
1305 s->increment_refcount();
1306 to_cp->symbol_at_put(to_i, s);
1307 } break;
1308
1309 case JVM_CONSTANT_MethodType:
1310 case JVM_CONSTANT_MethodTypeInError:
1311 {
1312 jint k = from_cp->method_type_index_at_error_ok(from_i);
1313 to_cp->method_type_index_at_put(to_i, k);
1314 } break;
1315
1316 case JVM_CONSTANT_MethodHandle:
1317 case JVM_CONSTANT_MethodHandleInError:
1318 {
1319 int k1 = from_cp->method_handle_ref_kind_at_error_ok(from_i);
1320 int k2 = from_cp->method_handle_index_at_error_ok(from_i);
1321 to_cp->method_handle_index_at_put(to_i, k1, k2);
1322 } break;
1323
1324 case JVM_CONSTANT_InvokeDynamic:
1325 {
1326 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1327 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1328 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1329 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1330 } break;
1331
1332 // Invalid is used as the tag for the second constant pool entry
1333 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1334 // not be seen by itself.
1335 case JVM_CONSTANT_Invalid: // fall through
1336
1337 default:
1338 {
1339 ShouldNotReachHere();
1340 } break;
1341 }
1342 } // end copy_entry_to()
1343
1344
1345 // Search constant pool search_cp for an entry that matches this
1346 // constant pool's entry at pattern_i. Returns the index of a
1347 // matching entry or zero (0) if there is no matching entry.
1348 int ConstantPool::find_matching_entry(int pattern_i,
1349 constantPoolHandle search_cp, TRAPS) {
1350
1351 // index zero (0) is not used
1352 for (int i = 1; i < search_cp->length(); i++) {
1353 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1354 if (found) {
1355 return i;
1356 }
1357 }
1358
1359 return 0; // entry not found; return unused index zero (0)
1360 } // end find_matching_entry()
1361
1362
1363 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1364 // cp2's bootstrap specifier at idx2.
1365 bool ConstantPool::compare_operand_to(int idx1, constantPoolHandle cp2, int idx2, TRAPS) {
1366 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1367 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1368 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1369
1370 if (!match) {
1371 return false;
1372 }
1373 int argc = operand_argument_count_at(idx1);
1374 if (argc == cp2->operand_argument_count_at(idx2)) {
1375 for (int j = 0; j < argc; j++) {
1376 k1 = operand_argument_index_at(idx1, j);
1377 k2 = cp2->operand_argument_index_at(idx2, j);
1378 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1379 if (!match) {
1380 return false;
1381 }
1382 }
1383 return true; // got through loop; all elements equal
1384 }
1385 return false;
1386 } // end compare_operand_to()
1387
1388 // Search constant pool search_cp for a bootstrap specifier that matches
1389 // this constant pool's bootstrap specifier at pattern_i index.
1390 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1391 int ConstantPool::find_matching_operand(int pattern_i,
1392 constantPoolHandle search_cp, int search_len, TRAPS) {
1393 for (int i = 0; i < search_len; i++) {
1394 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1395 if (found) {
1396 return i;
1397 }
1398 }
1399 return -1; // bootstrap specifier not found; return unused index (-1)
1400 } // end find_matching_operand()
1401
1402
1403 #ifndef PRODUCT
1404
1405 const char* ConstantPool::printable_name_at(int which) {
1406
1407 constantTag tag = tag_at(which);
1408
1409 if (tag.is_string()) {
1410 return string_at_noresolve(which);
1411 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1412 return klass_name_at(which)->as_C_string();
1413 } else if (tag.is_symbol()) {
1414 return symbol_at(which)->as_C_string();
1415 }
1416 return "";
1417 }
1418
1419 #endif // PRODUCT
1420
1421
1422 // JVMTI GetConstantPool support
1423
1424 // For debugging of constant pool
1425 const bool debug_cpool = false;
1426
1427 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1428
1429 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1430 const char* WARN_MSG = "Must not be such entry!";
1431 jint size = 0;
1432 u2 idx1, idx2;
1433
1434 for (jint idx = 1; idx < cnt; idx++) {
1435 jint ent_size = 0;
1436 u1 tag = *bytes++;
1437 size++; // count tag
1438
1439 printf("const #%03d, tag: %02d ", idx, tag);
1440 switch(tag) {
1441 case JVM_CONSTANT_Invalid: {
1442 printf("Invalid");
1443 break;
1444 }
1445 case JVM_CONSTANT_Unicode: {
1446 printf("Unicode %s", WARN_MSG);
1447 break;
1448 }
1449 case JVM_CONSTANT_Utf8: {
1450 u2 len = Bytes::get_Java_u2(bytes);
1451 char str[128];
1452 if (len > 127) {
1453 len = 127;
1454 }
1455 strncpy(str, (char *) (bytes+2), len);
1456 str[len] = '\0';
1457 printf("Utf8 \"%s\"", str);
1458 ent_size = 2 + len;
1459 break;
1460 }
1461 case JVM_CONSTANT_Integer: {
1462 u4 val = Bytes::get_Java_u4(bytes);
1463 printf("int %d", *(int *) &val);
1464 ent_size = 4;
1465 break;
1466 }
1467 case JVM_CONSTANT_Float: {
1468 u4 val = Bytes::get_Java_u4(bytes);
1469 printf("float %5.3ff", *(float *) &val);
1470 ent_size = 4;
1471 break;
1472 }
1473 case JVM_CONSTANT_Long: {
1474 u8 val = Bytes::get_Java_u8(bytes);
1475 printf("long "INT64_FORMAT, (int64_t) *(jlong *) &val);
1476 ent_size = 8;
1477 idx++; // Long takes two cpool slots
1478 break;
1479 }
1480 case JVM_CONSTANT_Double: {
1481 u8 val = Bytes::get_Java_u8(bytes);
1482 printf("double %5.3fd", *(jdouble *)&val);
1483 ent_size = 8;
1484 idx++; // Double takes two cpool slots
1485 break;
1486 }
1487 case JVM_CONSTANT_Class: {
1488 idx1 = Bytes::get_Java_u2(bytes);
1489 printf("class #%03d", idx1);
1490 ent_size = 2;
1491 break;
1492 }
1493 case JVM_CONSTANT_String: {
1494 idx1 = Bytes::get_Java_u2(bytes);
1495 printf("String #%03d", idx1);
1496 ent_size = 2;
1497 break;
1498 }
1499 case JVM_CONSTANT_Fieldref: {
1500 idx1 = Bytes::get_Java_u2(bytes);
1501 idx2 = Bytes::get_Java_u2(bytes+2);
1502 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1503 ent_size = 4;
1504 break;
1505 }
1506 case JVM_CONSTANT_Methodref: {
1507 idx1 = Bytes::get_Java_u2(bytes);
1508 idx2 = Bytes::get_Java_u2(bytes+2);
1509 printf("Method #%03d, #%03d", idx1, idx2);
1510 ent_size = 4;
1511 break;
1512 }
1513 case JVM_CONSTANT_InterfaceMethodref: {
1514 idx1 = Bytes::get_Java_u2(bytes);
1515 idx2 = Bytes::get_Java_u2(bytes+2);
1516 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1517 ent_size = 4;
1518 break;
1519 }
1520 case JVM_CONSTANT_NameAndType: {
1521 idx1 = Bytes::get_Java_u2(bytes);
1522 idx2 = Bytes::get_Java_u2(bytes+2);
1523 printf("NameAndType #%03d, #%03d", idx1, idx2);
1524 ent_size = 4;
1525 break;
1526 }
1527 case JVM_CONSTANT_ClassIndex: {
1528 printf("ClassIndex %s", WARN_MSG);
1529 break;
1530 }
1531 case JVM_CONSTANT_UnresolvedClass: {
1532 printf("UnresolvedClass: %s", WARN_MSG);
1533 break;
1534 }
1535 case JVM_CONSTANT_UnresolvedClassInError: {
1536 printf("UnresolvedClassInErr: %s", WARN_MSG);
1537 break;
1538 }
1539 case JVM_CONSTANT_StringIndex: {
1540 printf("StringIndex: %s", WARN_MSG);
1541 break;
1542 }
1543 }
1544 printf(";\n");
1545 bytes += ent_size;
1546 size += ent_size;
1547 }
1548 printf("Cpool size: %d\n", size);
1549 fflush(0);
1550 return;
1551 } /* end print_cpool_bytes */
1552
1553
1554 // Returns size of constant pool entry.
1555 jint ConstantPool::cpool_entry_size(jint idx) {
1556 switch(tag_at(idx).value()) {
1557 case JVM_CONSTANT_Invalid:
1558 case JVM_CONSTANT_Unicode:
1559 return 1;
1560
1561 case JVM_CONSTANT_Utf8:
1562 return 3 + symbol_at(idx)->utf8_length();
1563
1564 case JVM_CONSTANT_Class:
1565 case JVM_CONSTANT_String:
1566 case JVM_CONSTANT_ClassIndex:
1567 case JVM_CONSTANT_UnresolvedClass:
1568 case JVM_CONSTANT_UnresolvedClassInError:
1569 case JVM_CONSTANT_StringIndex:
1570 case JVM_CONSTANT_MethodType:
1571 case JVM_CONSTANT_MethodTypeInError:
1572 return 3;
1573
1574 case JVM_CONSTANT_MethodHandle:
1575 case JVM_CONSTANT_MethodHandleInError:
1576 return 4; //tag, ref_kind, ref_index
1577
1578 case JVM_CONSTANT_Integer:
1579 case JVM_CONSTANT_Float:
1580 case JVM_CONSTANT_Fieldref:
1581 case JVM_CONSTANT_Methodref:
1582 case JVM_CONSTANT_InterfaceMethodref:
1583 case JVM_CONSTANT_NameAndType:
1584 return 5;
1585
1586 case JVM_CONSTANT_InvokeDynamic:
1587 // u1 tag, u2 bsm, u2 nt
1588 return 5;
1589
1590 case JVM_CONSTANT_Long:
1591 case JVM_CONSTANT_Double:
1592 return 9;
1593 }
1594 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1595 return 1;
1596 } /* end cpool_entry_size */
1597
1598
1599 // SymbolHashMap is used to find a constant pool index from a string.
1600 // This function fills in SymbolHashMaps, one for utf8s and one for
1601 // class names, returns size of the cpool raw bytes.
1602 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1603 SymbolHashMap *classmap) {
1604 jint size = 0;
1605
1606 for (u2 idx = 1; idx < length(); idx++) {
1607 u2 tag = tag_at(idx).value();
1608 size += cpool_entry_size(idx);
1609
1610 switch(tag) {
1611 case JVM_CONSTANT_Utf8: {
1612 Symbol* sym = symbol_at(idx);
1613 symmap->add_entry(sym, idx);
1614 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1615 break;
1616 }
1617 case JVM_CONSTANT_Class:
1618 case JVM_CONSTANT_UnresolvedClass:
1619 case JVM_CONSTANT_UnresolvedClassInError: {
1620 Symbol* sym = klass_name_at(idx);
1621 classmap->add_entry(sym, idx);
1622 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1623 break;
1624 }
1625 case JVM_CONSTANT_Long:
1626 case JVM_CONSTANT_Double: {
1627 idx++; // Both Long and Double take two cpool slots
1628 break;
1629 }
1630 }
1631 }
1632 return size;
1633 } /* end hash_utf8_entries_to */
1634
1635
1636 // Copy cpool bytes.
1637 // Returns:
1638 // 0, in case of OutOfMemoryError
1639 // -1, in case of internal error
1640 // > 0, count of the raw cpool bytes that have been copied
1641 int ConstantPool::copy_cpool_bytes(int cpool_size,
1642 SymbolHashMap* tbl,
1643 unsigned char *bytes) {
1644 u2 idx1, idx2;
1645 jint size = 0;
1646 jint cnt = length();
1647 unsigned char *start_bytes = bytes;
1648
1649 for (jint idx = 1; idx < cnt; idx++) {
1650 u1 tag = tag_at(idx).value();
1651 jint ent_size = cpool_entry_size(idx);
1652
1653 assert(size + ent_size <= cpool_size, "Size mismatch");
1654
1655 *bytes = tag;
1656 DBG(printf("#%03hd tag=%03hd, ", idx, tag));
1657 switch(tag) {
1658 case JVM_CONSTANT_Invalid: {
1659 DBG(printf("JVM_CONSTANT_Invalid"));
1660 break;
1661 }
1662 case JVM_CONSTANT_Unicode: {
1663 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1664 DBG(printf("JVM_CONSTANT_Unicode"));
1665 break;
1666 }
1667 case JVM_CONSTANT_Utf8: {
1668 Symbol* sym = symbol_at(idx);
1669 char* str = sym->as_utf8();
1670 // Warning! It's crashing on x86 with len = sym->utf8_length()
1671 int len = (int) strlen(str);
1672 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1673 for (int i = 0; i < len; i++) {
1674 bytes[3+i] = (u1) str[i];
1675 }
1676 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1677 break;
1678 }
1679 case JVM_CONSTANT_Integer: {
1680 jint val = int_at(idx);
1681 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1682 break;
1683 }
1684 case JVM_CONSTANT_Float: {
1685 jfloat val = float_at(idx);
1686 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1687 break;
1688 }
1689 case JVM_CONSTANT_Long: {
1690 jlong val = long_at(idx);
1691 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1692 idx++; // Long takes two cpool slots
1693 break;
1694 }
1695 case JVM_CONSTANT_Double: {
1696 jdouble val = double_at(idx);
1697 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1698 idx++; // Double takes two cpool slots
1699 break;
1700 }
1701 case JVM_CONSTANT_Class:
1702 case JVM_CONSTANT_UnresolvedClass:
1703 case JVM_CONSTANT_UnresolvedClassInError: {
1704 *bytes = JVM_CONSTANT_Class;
1705 Symbol* sym = klass_name_at(idx);
1706 idx1 = tbl->symbol_to_value(sym);
1707 assert(idx1 != 0, "Have not found a hashtable entry");
1708 Bytes::put_Java_u2((address) (bytes+1), idx1);
1709 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1710 break;
1711 }
1712 case JVM_CONSTANT_String: {
1713 *bytes = JVM_CONSTANT_String;
1714 Symbol* sym = unresolved_string_at(idx);
1715 idx1 = tbl->symbol_to_value(sym);
1716 assert(idx1 != 0, "Have not found a hashtable entry");
1717 Bytes::put_Java_u2((address) (bytes+1), idx1);
1718 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1719 break;
1720 }
1721 case JVM_CONSTANT_Fieldref:
1722 case JVM_CONSTANT_Methodref:
1723 case JVM_CONSTANT_InterfaceMethodref: {
1724 idx1 = uncached_klass_ref_index_at(idx);
1725 idx2 = uncached_name_and_type_ref_index_at(idx);
1726 Bytes::put_Java_u2((address) (bytes+1), idx1);
1727 Bytes::put_Java_u2((address) (bytes+3), idx2);
1728 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1729 break;
1730 }
1731 case JVM_CONSTANT_NameAndType: {
1732 idx1 = name_ref_index_at(idx);
1733 idx2 = signature_ref_index_at(idx);
1734 Bytes::put_Java_u2((address) (bytes+1), idx1);
1735 Bytes::put_Java_u2((address) (bytes+3), idx2);
1736 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1737 break;
1738 }
1739 case JVM_CONSTANT_ClassIndex: {
1740 *bytes = JVM_CONSTANT_Class;
1741 idx1 = klass_index_at(idx);
1742 Bytes::put_Java_u2((address) (bytes+1), idx1);
1743 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1744 break;
1745 }
1746 case JVM_CONSTANT_StringIndex: {
1747 *bytes = JVM_CONSTANT_String;
1748 idx1 = string_index_at(idx);
1749 Bytes::put_Java_u2((address) (bytes+1), idx1);
1750 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1751 break;
1752 }
1753 case JVM_CONSTANT_MethodHandle:
1754 case JVM_CONSTANT_MethodHandleInError: {
1755 *bytes = JVM_CONSTANT_MethodHandle;
1756 int kind = method_handle_ref_kind_at_error_ok(idx);
1757 idx1 = method_handle_index_at_error_ok(idx);
1758 *(bytes+1) = (unsigned char) kind;
1759 Bytes::put_Java_u2((address) (bytes+2), idx1);
1760 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1761 break;
1762 }
1763 case JVM_CONSTANT_MethodType:
1764 case JVM_CONSTANT_MethodTypeInError: {
1765 *bytes = JVM_CONSTANT_MethodType;
1766 idx1 = method_type_index_at_error_ok(idx);
1767 Bytes::put_Java_u2((address) (bytes+1), idx1);
1768 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1769 break;
1770 }
1771 case JVM_CONSTANT_InvokeDynamic: {
1772 *bytes = tag;
1773 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1774 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1775 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1776 Bytes::put_Java_u2((address) (bytes+1), idx1);
1777 Bytes::put_Java_u2((address) (bytes+3), idx2);
1778 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1779 break;
1780 }
1781 }
1782 DBG(printf("\n"));
1783 bytes += ent_size;
1784 size += ent_size;
1785 }
1786 assert(size == cpool_size, "Size mismatch");
1787
1788 // Keep temorarily for debugging until it's stable.
1789 DBG(print_cpool_bytes(cnt, start_bytes));
1790 return (int)(bytes - start_bytes);
1791 } /* end copy_cpool_bytes */
1792
1793 #undef DBG
1794
1795
1796 void ConstantPool::set_on_stack(const bool value) {
1797 if (value) {
1798 int old_flags = *const_cast<volatile int *>(&_flags);
1799 while ((old_flags & _on_stack) == 0) {
1800 int new_flags = old_flags | _on_stack;
1801 int result = Atomic::cmpxchg(new_flags, &_flags, old_flags);
1802
1803 if (result == old_flags) {
1804 // Succeeded.
1805 MetadataOnStackMark::record(this, Thread::current());
1806 return;
1807 }
1808 old_flags = result;
1809 }
1810 } else {
1811 // Clearing is done single-threadedly.
1812 _flags &= ~_on_stack;
1813 }
1814 }
1815
1816 // JSR 292 support for patching constant pool oops after the class is linked and
1817 // the oop array for resolved references are created.
1818 // We can't do this during classfile parsing, which is how the other indexes are
1819 // patched. The other patches are applied early for some error checking
1820 // so only defer the pseudo_strings.
1821 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
1822 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
1823 Handle patch = cp_patches->at(index);
1824 if (patch.not_null()) {
1825 assert (tag_at(index).is_string(), "should only be string left");
1826 // Patching a string means pre-resolving it.
1827 // The spelling in the constant pool is ignored.
1828 // The constant reference may be any object whatever.
1829 // If it is not a real interned string, the constant is referred
1830 // to as a "pseudo-string", and must be presented to the CP
1831 // explicitly, because it may require scavenging.
1832 int obj_index = cp_to_object_index(index);
1833 pseudo_string_at_put(index, obj_index, patch());
1834 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
1835 }
1836 }
1837 #ifdef ASSERT
1838 // Ensure that all the patches have been used.
1839 for (int index = 0; index < cp_patches->length(); index++) {
1840 assert(cp_patches->at(index).is_null(),
1841 err_msg("Unused constant pool patch at %d in class file %s",
1842 index,
1843 pool_holder()->external_name()));
1844 }
1845 #endif // ASSERT
1846 }
1847
1848 #ifndef PRODUCT
1849
1850 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
1851 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
1852 guarantee(obj->is_constantPool(), "object must be constant pool");
1853 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
1854 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
1855
1856 for (int i = 0; i< cp->length(); i++) {
1857 if (cp->tag_at(i).is_unresolved_klass()) {
1858 // This will force loading of the class
1859 Klass* klass = cp->klass_at(i, CHECK);
1860 if (klass->oop_is_instance()) {
1861 // Force initialization of class
1862 InstanceKlass::cast(klass)->initialize(CHECK);
1863 }
1864 }
1865 }
1866 }
1867
1868 #endif
1869
1870
1871 // Printing
1872
1873 void ConstantPool::print_on(outputStream* st) const {
1874 assert(is_constantPool(), "must be constantPool");
1875 st->print_cr("%s", internal_name());
1876 if (flags() != 0) {
1877 st->print(" - flags: 0x%x", flags());
1878 if (has_preresolution()) st->print(" has_preresolution");
1879 if (on_stack()) st->print(" on_stack");
1880 st->cr();
1881 }
1882 if (pool_holder() != NULL) {
1883 st->print_cr(" - holder: " INTPTR_FORMAT, pool_holder());
1884 }
1885 st->print_cr(" - cache: " INTPTR_FORMAT, cache());
1886 st->print_cr(" - resolved_references: " INTPTR_FORMAT, (void *)resolved_references());
1887 st->print_cr(" - reference_map: " INTPTR_FORMAT, reference_map());
1888
1889 for (int index = 1; index < length(); index++) { // Index 0 is unused
1890 ((ConstantPool*)this)->print_entry_on(index, st);
1891 switch (tag_at(index).value()) {
1892 case JVM_CONSTANT_Long :
1893 case JVM_CONSTANT_Double :
1894 index++; // Skip entry following eigth-byte constant
1895 }
1896
1897 }
1898 st->cr();
1899 }
1900
1901 // Print one constant pool entry
1902 void ConstantPool::print_entry_on(const int index, outputStream* st) {
1903 EXCEPTION_MARK;
1904 st->print(" - %3d : ", index);
1905 tag_at(index).print_on(st);
1906 st->print(" : ");
1907 switch (tag_at(index).value()) {
1908 case JVM_CONSTANT_Class :
1909 { Klass* k = klass_at(index, CATCH);
1910 guarantee(k != NULL, "need klass");
1911 k->print_value_on(st);
1912 st->print(" {0x%lx}", (address)k);
1913 }
1914 break;
1915 case JVM_CONSTANT_Fieldref :
1916 case JVM_CONSTANT_Methodref :
1917 case JVM_CONSTANT_InterfaceMethodref :
1918 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
1919 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
1920 break;
1921 case JVM_CONSTANT_String :
1922 if (is_pseudo_string_at(index)) {
1923 oop anObj = pseudo_string_at(index);
1924 anObj->print_value_on(st);
1925 st->print(" {0x%lx}", (address)anObj);
1926 } else {
1927 unresolved_string_at(index)->print_value_on(st);
1928 }
1929 break;
1930 case JVM_CONSTANT_Integer :
1931 st->print("%d", int_at(index));
1932 break;
1933 case JVM_CONSTANT_Float :
1934 st->print("%f", float_at(index));
1935 break;
1936 case JVM_CONSTANT_Long :
1937 st->print_jlong(long_at(index));
1938 break;
1939 case JVM_CONSTANT_Double :
1940 st->print("%lf", double_at(index));
1941 break;
1942 case JVM_CONSTANT_NameAndType :
1943 st->print("name_index=%d", name_ref_index_at(index));
1944 st->print(" signature_index=%d", signature_ref_index_at(index));
1945 break;
1946 case JVM_CONSTANT_Utf8 :
1947 symbol_at(index)->print_value_on(st);
1948 break;
1949 case JVM_CONSTANT_UnresolvedClass : // fall-through
1950 case JVM_CONSTANT_UnresolvedClassInError: {
1951 CPSlot entry = slot_at(index);
1952 if (entry.is_resolved()) {
1953 entry.get_klass()->print_value_on(st);
1954 } else {
1955 entry.get_symbol()->print_value_on(st);
1956 }
1957 }
1958 break;
1959 case JVM_CONSTANT_MethodHandle :
1960 case JVM_CONSTANT_MethodHandleInError :
1961 st->print("ref_kind=%d", method_handle_ref_kind_at_error_ok(index));
1962 st->print(" ref_index=%d", method_handle_index_at_error_ok(index));
1963 break;
1964 case JVM_CONSTANT_MethodType :
1965 case JVM_CONSTANT_MethodTypeInError :
1966 st->print("signature_index=%d", method_type_index_at_error_ok(index));
1967 break;
1968 case JVM_CONSTANT_InvokeDynamic :
1969 {
1970 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
1971 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
1972 int argc = invoke_dynamic_argument_count_at(index);
1973 if (argc > 0) {
1974 for (int arg_i = 0; arg_i < argc; arg_i++) {
1975 int arg = invoke_dynamic_argument_index_at(index, arg_i);
1976 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
1977 }
1978 st->print("}");
1979 }
1980 }
1981 break;
1982 default:
1983 ShouldNotReachHere();
1984 break;
1985 }
1986 st->cr();
1987 }
1988
1989 void ConstantPool::print_value_on(outputStream* st) const {
1990 assert(is_constantPool(), "must be constantPool");
1991 st->print("constant pool [%d]", length());
1992 if (has_preresolution()) st->print("/preresolution");
1993 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
1994 print_address_on(st);
1995 st->print(" for ");
1996 pool_holder()->print_value_on(st);
1997 if (pool_holder() != NULL) {
1998 bool extra = (pool_holder()->constants() != this);
1999 if (extra) st->print(" (extra)");
2000 }
2001 if (cache() != NULL) {
2002 st->print(" cache=" PTR_FORMAT, cache());
2003 }
2004 }
2005
2006 #if INCLUDE_SERVICES
2007 // Size Statistics
2008 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2009 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2010 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2011 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2012 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2013 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2014
2015 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2016 sz->_cp_refmap_bytes;
2017 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2018 }
2019 #endif // INCLUDE_SERVICES
2020
2021 // Verification
2022
2023 void ConstantPool::verify_on(outputStream* st) {
2024 guarantee(is_constantPool(), "object must be constant pool");
2025 for (int i = 0; i< length(); i++) {
2026 constantTag tag = tag_at(i);
2027 CPSlot entry = slot_at(i);
2028 if (tag.is_klass()) {
2029 if (entry.is_resolved()) {
2030 guarantee(entry.get_klass()->is_klass(), "should be klass");
2031 }
2032 } else if (tag.is_unresolved_klass()) {
2033 if (entry.is_resolved()) {
2034 guarantee(entry.get_klass()->is_klass(), "should be klass");
2035 }
2036 } else if (tag.is_symbol()) {
2037 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2038 } else if (tag.is_string()) {
2039 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2040 }
2041 }
2042 if (cache() != NULL) {
2043 // Note: cache() can be NULL before a class is completely setup or
2044 // in temporary constant pools used during constant pool merging
2045 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2046 }
2047 if (pool_holder() != NULL) {
2048 // Note: pool_holder() can be NULL in temporary constant pools
2049 // used during constant pool merging
2050 guarantee(pool_holder()->is_klass(), "should be klass");
2051 }
2052 }
2053
2054
2055 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2056 char *str = sym->as_utf8();
2057 unsigned int hash = compute_hash(str, sym->utf8_length());
2058 unsigned int index = hash % table_size();
2059
2060 // check if already in map
2061 // we prefer the first entry since it is more likely to be what was used in
2062 // the class file
2063 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2064 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2065 if (en->hash() == hash && en->symbol() == sym) {
2066 return; // already there
2067 }
2068 }
2069
2070 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2071 entry->set_next(bucket(index));
2072 _buckets[index].set_entry(entry);
2073 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2074 }
2075
2076 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2077 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2078 char *str = sym->as_utf8();
2079 int len = sym->utf8_length();
2080 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2081 unsigned int index = hash % table_size();
2082 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2083 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2084 if (en->hash() == hash && en->symbol() == sym) {
2085 return en;
2086 }
2087 }
2088 return NULL;
2089 }