1 /*
2 * Copyright (c) 1997, 2017, 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.inline.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/metaspaceClosure.hpp"
36 #include "memory/metaspaceShared.hpp"
37 #include "memory/oopFactory.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "oops/constantPool.hpp"
40 #include "oops/instanceKlass.hpp"
41 #include "oops/objArrayKlass.hpp"
42 #include "oops/objArrayOop.inline.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "prims/jvm.h"
45 #include "runtime/fieldType.hpp"
46 #include "runtime/init.hpp"
47 #include "runtime/javaCalls.hpp"
48 #include "runtime/signature.hpp"
49 #include "runtime/vframe.hpp"
50 #include "utilities/copy.hpp"
51 #if INCLUDE_ALL_GCS
52 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
53 #endif // INCLUDE_ALL_GCS
54
55 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
56 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
57 int size = ConstantPool::size(length);
58 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
59 }
60
61 #ifdef ASSERT
62
63 // MetaspaceObj allocation invariant is calloc equivalent memory
64 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
65 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
66 assert(tags != NULL, "invariant");
67 const int length = tags->length();
68 for (int index = 0; index < length; ++index) {
69 if (JVM_CONSTANT_Invalid != tags->at(index)) {
70 return false;
71 }
72 }
73 return true;
74 }
75
76 #endif
77
78 ConstantPool::ConstantPool(Array<u1>* tags) :
79 _tags(tags),
80 _length(tags->length()) {
81
82 assert(_tags != NULL, "invariant");
83 assert(tags->length() == _length, "invariant");
84 assert(tag_array_is_zero_initialized(tags), "invariant");
85 assert(0 == flags(), "invariant");
86 assert(0 == version(), "invariant");
87 assert(NULL == _pool_holder, "invariant");
88 }
89
90 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
91 if (cache() != NULL) {
92 MetadataFactory::free_metadata(loader_data, cache());
93 set_cache(NULL);
94 }
95
96 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
97 set_resolved_klasses(NULL);
98
99 MetadataFactory::free_array<jushort>(loader_data, operands());
100 set_operands(NULL);
101
102 release_C_heap_structures();
103
104 // free tag array
105 MetadataFactory::free_array<u1>(loader_data, tags());
106 set_tags(NULL);
107 }
108
109 void ConstantPool::release_C_heap_structures() {
110 // walk constant pool and decrement symbol reference counts
111 unreference_symbols();
112 }
113
114 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
115 log_trace(cds)("Iter(ConstantPool): %p", this);
116
117 it->push(&_tags, MetaspaceClosure::_writable);
118 it->push(&_cache);
119 it->push(&_pool_holder);
120 it->push(&_operands);
121 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
122
123 for (int i = 0; i < length(); i++) {
124 // The only MSO's embedded in the CP entries are Symbols:
125 // JVM_CONSTANT_String (normal and pseudo)
126 // JVM_CONSTANT_Utf8
127 constantTag ctag = tag_at(i);
128 if (ctag.is_string() || ctag.is_utf8()) {
129 it->push(symbol_at_addr(i));
130 }
131 }
132 }
133
134 objArrayOop ConstantPool::resolved_references() const {
135 return (objArrayOop)_cache->resolved_references();
136 }
137
138 // Create resolved_references array and mapping array for original cp indexes
139 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
140 // to map it back for resolving and some unlikely miscellaneous uses.
141 // The objects created by invokedynamic are appended to this list.
142 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
143 const intStack& reference_map,
144 int constant_pool_map_length,
145 TRAPS) {
146 // Initialized the resolved object cache.
147 int map_length = reference_map.length();
148 if (map_length > 0) {
149 // Only need mapping back to constant pool entries. The map isn't used for
150 // invokedynamic resolved_reference entries. For invokedynamic entries,
151 // the constant pool cache index has the mapping back to both the constant
152 // pool and to the resolved reference index.
153 if (constant_pool_map_length > 0) {
154 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
155
156 for (int i = 0; i < constant_pool_map_length; i++) {
157 int x = reference_map.at(i);
158 assert(x == (int)(jushort) x, "klass index is too big");
159 om->at_put(i, (jushort)x);
160 }
161 set_reference_map(om);
162 }
163
164 // Create Java array for holding resolved strings, methodHandles,
165 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
166 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
167 Handle refs_handle (THREAD, (oop)stom); // must handleize.
168 set_resolved_references(loader_data->add_handle(refs_handle));
169 }
170 }
171
172 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
173 // A ConstantPool can't possibly have 0xffff valid class entries,
174 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
175 // entry for the class's name. So at most we will have 0xfffe class entries.
176 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
177 // UnresolvedKlass entries that are temporarily created during class redefinition.
178 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
179 assert(resolved_klasses() == NULL, "sanity");
180 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
181 set_resolved_klasses(rk);
182 }
183
184 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
185 int len = length();
186 int num_klasses = 0;
187 for (int i = 1; i <len; i++) {
188 switch (tag_at(i).value()) {
189 case JVM_CONSTANT_ClassIndex:
190 {
191 const int class_index = klass_index_at(i);
192 unresolved_klass_at_put(i, class_index, num_klasses++);
193 }
194 break;
195 #ifndef PRODUCT
196 case JVM_CONSTANT_Class:
197 case JVM_CONSTANT_UnresolvedClass:
198 case JVM_CONSTANT_UnresolvedClassInError:
199 // All of these should have been reverted back to ClassIndex before calling
200 // this function.
201 ShouldNotReachHere();
202 #endif
203 }
204 }
205 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
206 }
207
208 // Anonymous class support:
209 void ConstantPool::klass_at_put(int class_index, int name_index, int resolved_klass_index, Klass* k, Symbol* name) {
210 assert(is_within_bounds(class_index), "index out of bounds");
211 assert(is_within_bounds(name_index), "index out of bounds");
212 assert((resolved_klass_index & 0xffff0000) == 0, "must be");
213 *int_at_addr(class_index) =
214 build_int_from_shorts((jushort)resolved_klass_index, (jushort)name_index);
215
216 symbol_at_put(name_index, name);
217 name->increment_refcount();
218 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
219 OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
220
221 // The interpreter assumes when the tag is stored, the klass is resolved
222 // and the Klass* non-NULL, so we need hardware store ordering here.
223 if (k != NULL) {
224 release_tag_at_put(class_index, JVM_CONSTANT_Class);
225 } else {
226 release_tag_at_put(class_index, JVM_CONSTANT_UnresolvedClass);
227 }
228 }
229
230 // Anonymous class support:
231 void ConstantPool::klass_at_put(int class_index, Klass* k) {
232 assert(k != NULL, "must be valid klass");
233 CPKlassSlot kslot = klass_slot_at(class_index);
234 int resolved_klass_index = kslot.resolved_klass_index();
235 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
236 OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
237
238 // The interpreter assumes when the tag is stored, the klass is resolved
239 // and the Klass* non-NULL, so we need hardware store ordering here.
240 release_tag_at_put(class_index, JVM_CONSTANT_Class);
241 }
242
243 #if INCLUDE_CDS_JAVA_HEAP
244 // Archive the resolved references
245 void ConstantPool::archive_resolved_references(Thread* THREAD) {
246 if (_cache == NULL) {
247 return; // nothing to do
248 }
249
250 InstanceKlass *ik = pool_holder();
251 if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
252 ik->is_shared_app_class())) {
253 // Archiving resolved references for classes from non-builtin loaders
254 // is not yet supported.
255 set_resolved_references(NULL);
256 return;
257 }
258
259 objArrayOop rr = resolved_references();
260 Array<u2>* ref_map = reference_map();
261 if (rr != NULL) {
262 int ref_map_len = ref_map == NULL ? 0 : ref_map->length();
263 int rr_len = rr->length();
264 for (int i = 0; i < rr_len; i++) {
265 oop p = rr->obj_at(i);
266 rr->obj_at_put(i, NULL);
267 if (p != NULL && i < ref_map_len) {
268 int index = object_to_cp_index(i);
269 // Skip the entry if the string hash code is 0 since the string
270 // is not included in the shared string_table, see StringTable::copy_shared_string.
271 if (tag_at(index).is_string() && java_lang_String::hash_code(p) != 0) {
272 oop op = StringTable::create_archived_string(p, THREAD);
273 // If the String object is not archived (possibly too large),
274 // NULL is returned. Also set it in the array, so we won't
275 // have a 'bad' reference in the archived resolved_reference
276 // array.
277 rr->obj_at_put(i, op);
278 }
279 }
280 }
281
282 oop archived = MetaspaceShared::archive_heap_object(rr, THREAD);
283 _cache->set_archived_references(archived);
284 set_resolved_references(NULL);
285 }
286 }
287 #endif
288
289 // CDS support. Create a new resolved_references array.
290 void ConstantPool::restore_unshareable_info(TRAPS) {
291 assert(is_constantPool(), "ensure C++ vtable is restored");
292 assert(on_stack(), "should always be set for shared constant pools");
293 assert(is_shared(), "should always be set for shared constant pools");
294 assert(_cache != NULL, "constant pool _cache should not be NULL");
295
296 // Only create the new resolved references array if it hasn't been attempted before
297 if (resolved_references() != NULL) return;
298
299 // restore the C++ vtable from the shared archive
300 restore_vtable();
301
302 if (SystemDictionary::Object_klass_loaded()) {
303 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
304 #if INCLUDE_CDS_JAVA_HEAP
305 if (MetaspaceShared::open_archive_heap_region_mapped() &&
306 _cache->archived_references() != NULL) {
307 oop archived = _cache->archived_references();
308 // Make sure GC knows the cached object is now live. This is necessary after
309 // initial GC marking and during concurrent marking as strong roots are only
310 // scanned during initial marking (at the start of the GC marking).
311 assert(UseG1GC, "Requires G1 GC");
312 G1SATBCardTableModRefBS::enqueue(archived);
313 // Create handle for the archived resolved reference array object
314 Handle refs_handle(THREAD, (oop)archived);
315 set_resolved_references(loader_data->add_handle(refs_handle));
316 } else
317 #endif
318 {
319 // No mapped archived resolved reference array
320 // Recreate the object array and add to ClassLoaderData.
321 int map_length = resolved_reference_length();
322 if (map_length > 0) {
323 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
324 Handle refs_handle(THREAD, (oop)stom); // must handleize.
325 set_resolved_references(loader_data->add_handle(refs_handle));
326 }
327 }
328 }
329 }
330
331 void ConstantPool::remove_unshareable_info() {
332 // Resolved references are not in the shared archive.
333 // Save the length for restoration. It is not necessarily the same length
334 // as reference_map.length() if invokedynamic is saved. It is needed when
335 // re-creating the resolved reference array if archived heap data cannot be map
336 // at runtime.
337 set_resolved_reference_length(
338 resolved_references() != NULL ? resolved_references()->length() : 0);
339
340 // If archiving heap objects is not allowed, clear the resolved references.
341 // Otherwise, it is cleared after the resolved references array is cached
342 // (see archive_resolved_references()).
343 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
344 set_resolved_references(NULL);
345 }
346
347 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
348 // The _on_stack flag is used to prevent ConstantPools from deallocation during
349 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
350 // we always set _on_stack to true to avoid having to change _flags during runtime.
351 _flags |= (_on_stack | _is_shared);
352 int num_klasses = 0;
353 for (int index = 1; index < length(); index++) { // Index 0 is unused
354 assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
355 if (tag_at(index).is_klass()) {
356 // This class was resolved as a side effect of executing Java code
357 // during dump time. We need to restore it back to an UnresolvedClass,
358 // so that the proper class loading and initialization can happen
359 // at runtime.
360 CPKlassSlot kslot = klass_slot_at(index);
361 int resolved_klass_index = kslot.resolved_klass_index();
362 int name_index = kslot.name_index();
363 assert(tag_at(name_index).is_symbol(), "sanity");
364 resolved_klasses()->at_put(resolved_klass_index, NULL);
365 tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
366 assert(klass_name_at(index) == symbol_at(name_index), "sanity");
367 }
368 }
369 if (cache() != NULL) {
370 cache()->remove_unshareable_info();
371 }
372 }
373
374 int ConstantPool::cp_to_object_index(int cp_index) {
375 // this is harder don't do this so much.
376 int i = reference_map()->find(cp_index);
377 // We might not find the index for jsr292 call.
378 return (i < 0) ? _no_index_sentinel : i;
379 }
380
381 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
382 resolved_references()->obj_at_put(obj_index, str);
383 }
384
385 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
386 ResourceMark rm;
387 int line_number = -1;
388 const char * source_file = NULL;
389 if (JavaThread::current()->has_last_Java_frame()) {
390 // try to identify the method which called this function.
391 vframeStream vfst(JavaThread::current());
392 if (!vfst.at_end()) {
393 line_number = vfst.method()->line_number_from_bci(vfst.bci());
394 Symbol* s = vfst.method()->method_holder()->source_file_name();
395 if (s != NULL) {
396 source_file = s->as_C_string();
397 }
398 }
399 }
400 if (k != this_cp->pool_holder()) {
401 // only print something if the classes are different
402 if (source_file != NULL) {
403 log_debug(class, resolve)("%s %s %s:%d",
404 this_cp->pool_holder()->external_name(),
405 k->external_name(), source_file, line_number);
406 } else {
407 log_debug(class, resolve)("%s %s",
408 this_cp->pool_holder()->external_name(),
409 k->external_name());
410 }
411 }
412 }
413
414 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
415 bool save_resolution_error, TRAPS) {
416 assert(THREAD->is_Java_thread(), "must be a Java thread");
417
418 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
419 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
420 // the entry and tag is not updated atomicly.
421 CPKlassSlot kslot = this_cp->klass_slot_at(which);
422 int resolved_klass_index = kslot.resolved_klass_index();
423 int name_index = kslot.name_index();
424 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
425
426 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
427 if (klass != NULL) {
428 return klass;
429 }
430
431 // This tag doesn't change back to unresolved class unless at a safepoint.
432 if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
433 // The original attempt to resolve this constant pool entry failed so find the
434 // class of the original error and throw another error of the same class
435 // (JVMS 5.4.3).
436 // If there is a detail message, pass that detail message to the error.
437 // The JVMS does not strictly require us to duplicate the same detail message,
438 // or any internal exception fields such as cause or stacktrace. But since the
439 // detail message is often a class name or other literal string, we will repeat it
440 // if we can find it in the symbol table.
441 throw_resolution_error(this_cp, which, CHECK_0);
442 ShouldNotReachHere();
443 }
444
445 Handle mirror_handle;
446 Symbol* name = this_cp->symbol_at(name_index);
447 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
448 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
449 Klass* k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
450 if (!HAS_PENDING_EXCEPTION) {
451 // preserve the resolved klass from unloading
452 mirror_handle = Handle(THREAD, k->java_mirror());
453 // Do access check for klasses
454 verify_constant_pool_resolve(this_cp, k, THREAD);
455 }
456
457 // Failed to resolve class. We must record the errors so that subsequent attempts
458 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
459 if (HAS_PENDING_EXCEPTION) {
460 if (save_resolution_error) {
461 save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
462 // If CHECK_NULL above doesn't return the exception, that means that
463 // some other thread has beaten us and has resolved the class.
464 // To preserve old behavior, we return the resolved class.
465 klass = this_cp->resolved_klasses()->at(resolved_klass_index);
466 assert(klass != NULL, "must be resolved if exception was cleared");
467 return klass;
468 } else {
469 return NULL; // return the pending exception
470 }
471 }
472
473 // Make this class loader depend upon the class loader owning the class reference
474 ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
475 this_key->record_dependency(k, CHECK_NULL); // Can throw OOM
476
477 // logging for class+resolve.
478 if (log_is_enabled(Debug, class, resolve)){
479 trace_class_resolution(this_cp, k);
480 }
481 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
482 OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
483 // The interpreter assumes when the tag is stored, the klass is resolved
484 // and the Klass* stored in _resolved_klasses is non-NULL, so we need
485 // hardware store ordering here.
486 this_cp->release_tag_at_put(which, JVM_CONSTANT_Class);
487 return k;
488 }
489
490
491 // Does not update ConstantPool* - to avoid any exception throwing. Used
492 // by compiler and exception handling. Also used to avoid classloads for
493 // instanceof operations. Returns NULL if the class has not been loaded or
494 // if the verification of constant pool failed
495 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
496 CPKlassSlot kslot = this_cp->klass_slot_at(which);
497 int resolved_klass_index = kslot.resolved_klass_index();
498 int name_index = kslot.name_index();
499 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
500
501 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
502 if (k != NULL) {
503 return k;
504 } else {
505 Thread *thread = Thread::current();
506 Symbol* name = this_cp->symbol_at(name_index);
507 oop loader = this_cp->pool_holder()->class_loader();
508 oop protection_domain = this_cp->pool_holder()->protection_domain();
509 Handle h_prot (thread, protection_domain);
510 Handle h_loader (thread, loader);
511 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
512
513 if (k != NULL) {
514 // Make sure that resolving is legal
515 EXCEPTION_MARK;
516 // return NULL if verification fails
517 verify_constant_pool_resolve(this_cp, k, THREAD);
518 if (HAS_PENDING_EXCEPTION) {
519 CLEAR_PENDING_EXCEPTION;
520 return NULL;
521 }
522 return k;
523 } else {
524 return k;
525 }
526 }
527 }
528
529
530 Klass* ConstantPool::klass_ref_at_if_loaded(const constantPoolHandle& this_cp, int which) {
531 return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
532 }
533
534
535 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
536 int which) {
537 if (cpool->cache() == NULL) return NULL; // nothing to load yet
538 int cache_index = decode_cpcache_index(which, true);
539 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
540 // FIXME: should be an assert
541 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
542 return NULL;
543 }
544 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
545 return e->method_if_resolved(cpool);
546 }
547
548
549 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
550 if (cpool->cache() == NULL) return false; // nothing to load yet
551 int cache_index = decode_cpcache_index(which, true);
552 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
553 return e->has_appendix();
554 }
555
556 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
557 if (cpool->cache() == NULL) return NULL; // nothing to load yet
558 int cache_index = decode_cpcache_index(which, true);
559 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
560 return e->appendix_if_resolved(cpool);
561 }
562
563
564 bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
565 if (cpool->cache() == NULL) return false; // nothing to load yet
566 int cache_index = decode_cpcache_index(which, true);
567 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
568 return e->has_method_type();
569 }
570
571 oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
572 if (cpool->cache() == NULL) return NULL; // nothing to load yet
573 int cache_index = decode_cpcache_index(which, true);
574 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
575 return e->method_type_if_resolved(cpool);
576 }
577
578
579 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
580 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
581 return symbol_at(name_index);
582 }
583
584
585 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
586 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
587 return symbol_at(signature_index);
588 }
589
590
591 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
592 int i = which;
593 if (!uncached && cache() != NULL) {
594 if (ConstantPool::is_invokedynamic_index(which)) {
595 // Invokedynamic index is index into the constant pool cache
596 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
597 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
598 assert(tag_at(pool_index).is_name_and_type(), "");
599 return pool_index;
600 }
601 // change byte-ordering and go via cache
602 i = remap_instruction_operand_from_cache(which);
603 } else {
604 if (tag_at(which).is_invoke_dynamic()) {
605 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
606 assert(tag_at(pool_index).is_name_and_type(), "");
607 return pool_index;
608 }
609 }
610 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
611 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
612 jint ref_index = *int_at_addr(i);
613 return extract_high_short_from_int(ref_index);
614 }
615
616 constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
617 int pool_index = which;
618 if (!uncached && cache() != NULL) {
619 if (ConstantPool::is_invokedynamic_index(which)) {
620 // Invokedynamic index is index into resolved_references
621 pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
622 } else {
623 // change byte-ordering and go via cache
624 pool_index = remap_instruction_operand_from_cache(which);
625 }
626 }
627 return tag_at(pool_index);
628 }
629
630 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
631 guarantee(!ConstantPool::is_invokedynamic_index(which),
632 "an invokedynamic instruction does not have a klass");
633 int i = which;
634 if (!uncached && cache() != NULL) {
635 // change byte-ordering and go via cache
636 i = remap_instruction_operand_from_cache(which);
637 }
638 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
639 jint ref_index = *int_at_addr(i);
640 return extract_low_short_from_int(ref_index);
641 }
642
643
644
645 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
646 int cpc_index = operand;
647 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
648 assert((int)(u2)cpc_index == cpc_index, "clean u2");
649 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
650 return member_index;
651 }
652
653
654 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
655 if (k->is_instance_klass() || k->is_objArray_klass()) {
656 InstanceKlass* holder = this_cp->pool_holder();
657 Klass* elem = k->is_instance_klass() ? k : ObjArrayKlass::cast(k)->bottom_klass();
658
659 // The element type could be a typeArray - we only need the access check if it is
660 // an reference to another class
661 if (elem->is_instance_klass()) {
662 LinkResolver::check_klass_accessability(holder, elem, CHECK);
663 }
664 }
665 }
666
667
668 int ConstantPool::name_ref_index_at(int which_nt) {
669 jint ref_index = name_and_type_at(which_nt);
670 return extract_low_short_from_int(ref_index);
671 }
672
673
674 int ConstantPool::signature_ref_index_at(int which_nt) {
675 jint ref_index = name_and_type_at(which_nt);
676 return extract_high_short_from_int(ref_index);
677 }
678
679
680 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
681 return klass_at(klass_ref_index_at(which), THREAD);
682 }
683
684 Symbol* ConstantPool::klass_name_at(int which) const {
685 return symbol_at(klass_slot_at(which).name_index());
686 }
687
688 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
689 jint ref_index = klass_ref_index_at(which);
690 return klass_at_noresolve(ref_index);
691 }
692
693 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
694 jint ref_index = uncached_klass_ref_index_at(which);
695 return klass_at_noresolve(ref_index);
696 }
697
698 char* ConstantPool::string_at_noresolve(int which) {
699 return unresolved_string_at(which)->as_C_string();
700 }
701
702 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
703 return FieldType::basic_type(symbol_at(which));
704 }
705
706
707 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
708 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
709 if (this_cp->tag_at(index).is_string()) {
710 this_cp->string_at(index, CHECK);
711 }
712 }
713 }
714
715 bool ConstantPool::resolve_class_constants(TRAPS) {
716 constantPoolHandle cp(THREAD, this);
717 for (int index = 1; index < length(); index++) { // Index 0 is unused
718 if (tag_at(index).is_string()) {
719 Symbol* sym = cp->unresolved_string_at(index);
720 // Look up only. Only resolve references to already interned strings.
721 oop str = StringTable::lookup(sym);
722 if (str != NULL) {
723 int cache_index = cp->cp_to_object_index(index);
724 cp->string_at_put(index, cache_index, str);
725 }
726 }
727 }
728 return true;
729 }
730
731 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
732 // Dig out the detailed message to reuse if possible
733 Symbol* message = java_lang_Throwable::detail_message(pending_exception);
734 if (message != NULL) {
735 return message;
736 }
737
738 // Return specific message for the tag
739 switch (tag.value()) {
740 case JVM_CONSTANT_UnresolvedClass:
741 // return the class name in the error message
742 message = this_cp->klass_name_at(which);
743 break;
744 case JVM_CONSTANT_MethodHandle:
745 // return the method handle name in the error message
746 message = this_cp->method_handle_name_ref_at(which);
747 break;
748 case JVM_CONSTANT_MethodType:
749 // return the method type signature in the error message
750 message = this_cp->method_type_signature_at(which);
751 break;
752 default:
753 ShouldNotReachHere();
754 }
755
756 return message;
757 }
758
759 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
760 Symbol* message = NULL;
761 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
762 assert(error != NULL && message != NULL, "checking");
763 CLEAR_PENDING_EXCEPTION;
764 ResourceMark rm;
765 THROW_MSG(error, message->as_C_string());
766 }
767
768 // If resolution for Class, MethodHandle or MethodType fails, save the exception
769 // in the resolution error table, so that the same exception is thrown again.
770 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
771 constantTag tag, TRAPS) {
772 Symbol* error = PENDING_EXCEPTION->klass()->name();
773
774 int error_tag = tag.error_value();
775
776 if (!PENDING_EXCEPTION->
777 is_a(SystemDictionary::LinkageError_klass())) {
778 // Just throw the exception and don't prevent these classes from
779 // being loaded due to virtual machine errors like StackOverflow
780 // and OutOfMemoryError, etc, or if the thread was hit by stop()
781 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
782 } else if (this_cp->tag_at(which).value() != error_tag) {
783 Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
784 SystemDictionary::add_resolution_error(this_cp, which, error, message);
785 // CAS in the tag. If a thread beat us to registering this error that's fine.
786 // If another thread resolved the reference, this is a race condition. This
787 // thread may have had a security manager or something temporary.
788 // This doesn't deterministically get an error. So why do we save this?
789 // We save this because jvmti can add classes to the bootclass path after
790 // this error, so it needs to get the same error if the error is first.
791 jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
792 (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
793 if (old_tag != error_tag && old_tag != tag.value()) {
794 // MethodHandles and MethodType doesn't change to resolved version.
795 assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
796 // Forget the exception and use the resolved class.
797 CLEAR_PENDING_EXCEPTION;
798 }
799 } else {
800 // some other thread put this in error state
801 throw_resolution_error(this_cp, which, CHECK);
802 }
803 }
804
805 // Called to resolve constants in the constant pool and return an oop.
806 // Some constant pool entries cache their resolved oop. This is also
807 // called to create oops from constants to use in arguments for invokedynamic
808 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS) {
809 oop result_oop = NULL;
810 Handle throw_exception;
811
812 if (cache_index == _possible_index_sentinel) {
813 // It is possible that this constant is one which is cached in the objects.
814 // We'll do a linear search. This should be OK because this usage is rare.
815 assert(index > 0, "valid index");
816 cache_index = this_cp->cp_to_object_index(index);
817 }
818 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
819 assert(index == _no_index_sentinel || index >= 0, "");
820
821 if (cache_index >= 0) {
822 result_oop = this_cp->resolved_references()->obj_at(cache_index);
823 if (result_oop != NULL) {
824 return result_oop;
825 // That was easy...
826 }
827 index = this_cp->object_to_cp_index(cache_index);
828 }
829
830 jvalue prim_value; // temp used only in a few cases below
831
832 constantTag tag = this_cp->tag_at(index);
833
834 switch (tag.value()) {
835
836 case JVM_CONSTANT_UnresolvedClass:
837 case JVM_CONSTANT_UnresolvedClassInError:
838 case JVM_CONSTANT_Class:
839 {
840 assert(cache_index == _no_index_sentinel, "should not have been set");
841 Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
842 // ldc wants the java mirror.
843 result_oop = resolved->java_mirror();
844 break;
845 }
846
847 case JVM_CONSTANT_String:
848 assert(cache_index != _no_index_sentinel, "should have been set");
849 if (this_cp->is_pseudo_string_at(index)) {
850 result_oop = this_cp->pseudo_string_at(index, cache_index);
851 break;
852 }
853 result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
854 break;
855
856 case JVM_CONSTANT_MethodHandleInError:
857 case JVM_CONSTANT_MethodTypeInError:
858 {
859 throw_resolution_error(this_cp, index, CHECK_NULL);
860 break;
861 }
862
863 case JVM_CONSTANT_MethodHandle:
864 {
865 int ref_kind = this_cp->method_handle_ref_kind_at(index);
866 int callee_index = this_cp->method_handle_klass_index_at(index);
867 Symbol* name = this_cp->method_handle_name_ref_at(index);
868 Symbol* signature = this_cp->method_handle_signature_ref_at(index);
869 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(index));
870 { ResourceMark rm(THREAD);
871 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
872 ref_kind, index, this_cp->method_handle_index_at(index),
873 callee_index, name->as_C_string(), signature->as_C_string());
874 }
875
876 Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
877
878 // Check constant pool method consistency
879 if ((callee->is_interface() && m_tag.is_method()) ||
880 ((!callee->is_interface() && m_tag.is_interface_method()))) {
881 ResourceMark rm(THREAD);
882 char buf[400];
883 jio_snprintf(buf, sizeof(buf),
884 "Inconsistent constant pool data in classfile for class %s. "
885 "Method %s%s at index %d is %s and should be %s",
886 callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
887 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
888 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
889 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
890 }
891
892 Klass* klass = this_cp->pool_holder();
893 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
894 callee, name, signature,
895 THREAD);
896 result_oop = value();
897 if (HAS_PENDING_EXCEPTION) {
898 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
899 }
900 break;
901 }
902
903 case JVM_CONSTANT_MethodType:
904 {
905 Symbol* signature = this_cp->method_type_signature_at(index);
906 { ResourceMark rm(THREAD);
907 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
908 index, this_cp->method_type_index_at(index),
909 signature->as_C_string());
910 }
911 Klass* klass = this_cp->pool_holder();
912 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
913 result_oop = value();
914 if (HAS_PENDING_EXCEPTION) {
915 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
916 }
917 break;
918 }
919
920 case JVM_CONSTANT_Integer:
921 assert(cache_index == _no_index_sentinel, "should not have been set");
922 prim_value.i = this_cp->int_at(index);
923 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
924 break;
925
926 case JVM_CONSTANT_Float:
927 assert(cache_index == _no_index_sentinel, "should not have been set");
928 prim_value.f = this_cp->float_at(index);
929 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
930 break;
931
932 case JVM_CONSTANT_Long:
933 assert(cache_index == _no_index_sentinel, "should not have been set");
934 prim_value.j = this_cp->long_at(index);
935 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
936 break;
937
938 case JVM_CONSTANT_Double:
939 assert(cache_index == _no_index_sentinel, "should not have been set");
940 prim_value.d = this_cp->double_at(index);
941 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
942 break;
943
944 default:
945 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
946 this_cp(), index, cache_index, tag.value()));
947 assert(false, "unexpected constant tag");
948 break;
949 }
950
951 if (cache_index >= 0) {
952 // Benign race condition: resolved_references may already be filled in.
953 // The important thing here is that all threads pick up the same result.
954 // It doesn't matter which racing thread wins, as long as only one
955 // result is used by all threads, and all future queries.
956 oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
957 if (old_result == NULL) {
958 return result_oop; // was installed
959 } else {
960 // Return the winning thread's result. This can be different than
961 // the result here for MethodHandles.
962 return old_result;
963 }
964 } else {
965 return result_oop;
966 }
967 }
968
969 oop ConstantPool::uncached_string_at(int which, TRAPS) {
970 Symbol* sym = unresolved_string_at(which);
971 oop str = StringTable::intern(sym, CHECK_(NULL));
972 assert(java_lang_String::is_instance(str), "must be string");
973 return str;
974 }
975
976
977 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
978 assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
979
980 Handle bsm;
981 int argc;
982 {
983 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
984 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
985 // It is accompanied by the optional arguments.
986 int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
987 oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
988 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
989 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
990 }
991
992 // Extract the optional static arguments.
993 argc = this_cp->invoke_dynamic_argument_count_at(index);
994 if (argc == 0) return bsm_oop;
995
996 bsm = Handle(THREAD, bsm_oop);
997 }
998
999 objArrayHandle info;
1000 {
1001 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
1002 info = objArrayHandle(THREAD, info_oop);
1003 }
1004
1005 info->obj_at_put(0, bsm());
1006 for (int i = 0; i < argc; i++) {
1007 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1008 oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
1009 info->obj_at_put(1+i, arg_oop);
1010 }
1011
1012 return info();
1013 }
1014
1015 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
1016 // If the string has already been interned, this entry will be non-null
1017 oop str = this_cp->resolved_references()->obj_at(obj_index);
1018 if (str != NULL) return str;
1019 Symbol* sym = this_cp->unresolved_string_at(which);
1020 str = StringTable::intern(sym, CHECK_(NULL));
1021 this_cp->string_at_put(which, obj_index, str);
1022 assert(java_lang_String::is_instance(str), "must be string");
1023 return str;
1024 }
1025
1026
1027 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
1028 // Names are interned, so we can compare Symbol*s directly
1029 Symbol* cp_name = klass_name_at(which);
1030 return (cp_name == k->name());
1031 }
1032
1033
1034 // Iterate over symbols and decrement ones which are Symbol*s
1035 // This is done during GC.
1036 // Only decrement the UTF8 symbols. Strings point to
1037 // these symbols but didn't increment the reference count.
1038 void ConstantPool::unreference_symbols() {
1039 for (int index = 1; index < length(); index++) { // Index 0 is unused
1040 constantTag tag = tag_at(index);
1041 if (tag.is_symbol()) {
1042 symbol_at(index)->decrement_refcount();
1043 }
1044 }
1045 }
1046
1047
1048 // Compare this constant pool's entry at index1 to the constant pool
1049 // cp2's entry at index2.
1050 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1051 int index2, TRAPS) {
1052
1053 // The error tags are equivalent to non-error tags when comparing
1054 jbyte t1 = tag_at(index1).non_error_value();
1055 jbyte t2 = cp2->tag_at(index2).non_error_value();
1056
1057 if (t1 != t2) {
1058 // Not the same entry type so there is nothing else to check. Note
1059 // that this style of checking will consider resolved/unresolved
1060 // class pairs as different.
1061 // From the ConstantPool* API point of view, this is correct
1062 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1063 // plays out in the context of ConstantPool* merging.
1064 return false;
1065 }
1066
1067 switch (t1) {
1068 case JVM_CONSTANT_Class:
1069 {
1070 Klass* k1 = klass_at(index1, CHECK_false);
1071 Klass* k2 = cp2->klass_at(index2, CHECK_false);
1072 if (k1 == k2) {
1073 return true;
1074 }
1075 } break;
1076
1077 case JVM_CONSTANT_ClassIndex:
1078 {
1079 int recur1 = klass_index_at(index1);
1080 int recur2 = cp2->klass_index_at(index2);
1081 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1082 if (match) {
1083 return true;
1084 }
1085 } break;
1086
1087 case JVM_CONSTANT_Double:
1088 {
1089 jdouble d1 = double_at(index1);
1090 jdouble d2 = cp2->double_at(index2);
1091 if (d1 == d2) {
1092 return true;
1093 }
1094 } break;
1095
1096 case JVM_CONSTANT_Fieldref:
1097 case JVM_CONSTANT_InterfaceMethodref:
1098 case JVM_CONSTANT_Methodref:
1099 {
1100 int recur1 = uncached_klass_ref_index_at(index1);
1101 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1102 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1103 if (match) {
1104 recur1 = uncached_name_and_type_ref_index_at(index1);
1105 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1106 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1107 if (match) {
1108 return true;
1109 }
1110 }
1111 } break;
1112
1113 case JVM_CONSTANT_Float:
1114 {
1115 jfloat f1 = float_at(index1);
1116 jfloat f2 = cp2->float_at(index2);
1117 if (f1 == f2) {
1118 return true;
1119 }
1120 } break;
1121
1122 case JVM_CONSTANT_Integer:
1123 {
1124 jint i1 = int_at(index1);
1125 jint i2 = cp2->int_at(index2);
1126 if (i1 == i2) {
1127 return true;
1128 }
1129 } break;
1130
1131 case JVM_CONSTANT_Long:
1132 {
1133 jlong l1 = long_at(index1);
1134 jlong l2 = cp2->long_at(index2);
1135 if (l1 == l2) {
1136 return true;
1137 }
1138 } break;
1139
1140 case JVM_CONSTANT_NameAndType:
1141 {
1142 int recur1 = name_ref_index_at(index1);
1143 int recur2 = cp2->name_ref_index_at(index2);
1144 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1145 if (match) {
1146 recur1 = signature_ref_index_at(index1);
1147 recur2 = cp2->signature_ref_index_at(index2);
1148 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1149 if (match) {
1150 return true;
1151 }
1152 }
1153 } break;
1154
1155 case JVM_CONSTANT_StringIndex:
1156 {
1157 int recur1 = string_index_at(index1);
1158 int recur2 = cp2->string_index_at(index2);
1159 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1160 if (match) {
1161 return true;
1162 }
1163 } break;
1164
1165 case JVM_CONSTANT_UnresolvedClass:
1166 {
1167 Symbol* k1 = klass_name_at(index1);
1168 Symbol* k2 = cp2->klass_name_at(index2);
1169 if (k1 == k2) {
1170 return true;
1171 }
1172 } break;
1173
1174 case JVM_CONSTANT_MethodType:
1175 {
1176 int k1 = method_type_index_at(index1);
1177 int k2 = cp2->method_type_index_at(index2);
1178 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1179 if (match) {
1180 return true;
1181 }
1182 } break;
1183
1184 case JVM_CONSTANT_MethodHandle:
1185 {
1186 int k1 = method_handle_ref_kind_at(index1);
1187 int k2 = cp2->method_handle_ref_kind_at(index2);
1188 if (k1 == k2) {
1189 int i1 = method_handle_index_at(index1);
1190 int i2 = cp2->method_handle_index_at(index2);
1191 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1192 if (match) {
1193 return true;
1194 }
1195 }
1196 } break;
1197
1198 case JVM_CONSTANT_InvokeDynamic:
1199 {
1200 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1201 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1202 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1203 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1204 // separate statements and variables because CHECK_false is used
1205 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1206 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1207 return (match_entry && match_operand);
1208 } break;
1209
1210 case JVM_CONSTANT_String:
1211 {
1212 Symbol* s1 = unresolved_string_at(index1);
1213 Symbol* s2 = cp2->unresolved_string_at(index2);
1214 if (s1 == s2) {
1215 return true;
1216 }
1217 } break;
1218
1219 case JVM_CONSTANT_Utf8:
1220 {
1221 Symbol* s1 = symbol_at(index1);
1222 Symbol* s2 = cp2->symbol_at(index2);
1223 if (s1 == s2) {
1224 return true;
1225 }
1226 } break;
1227
1228 // Invalid is used as the tag for the second constant pool entry
1229 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1230 // not be seen by itself.
1231 case JVM_CONSTANT_Invalid: // fall through
1232
1233 default:
1234 ShouldNotReachHere();
1235 break;
1236 }
1237
1238 return false;
1239 } // end compare_entry_to()
1240
1241
1242 // Resize the operands array with delta_len and delta_size.
1243 // Used in RedefineClasses for CP merge.
1244 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1245 int old_len = operand_array_length(operands());
1246 int new_len = old_len + delta_len;
1247 int min_len = (delta_len > 0) ? old_len : new_len;
1248
1249 int old_size = operands()->length();
1250 int new_size = old_size + delta_size;
1251 int min_size = (delta_size > 0) ? old_size : new_size;
1252
1253 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1254 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1255
1256 // Set index in the resized array for existing elements only
1257 for (int idx = 0; idx < min_len; idx++) {
1258 int offset = operand_offset_at(idx); // offset in original array
1259 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1260 }
1261 // Copy the bootstrap specifiers only
1262 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1263 new_ops->adr_at(2*new_len),
1264 (min_size - 2*min_len) * sizeof(u2));
1265 // Explicitly deallocate old operands array.
1266 // Note, it is not needed for 7u backport.
1267 if ( operands() != NULL) { // the safety check
1268 MetadataFactory::free_array<u2>(loader_data, operands());
1269 }
1270 set_operands(new_ops);
1271 } // end resize_operands()
1272
1273
1274 // Extend the operands array with the length and size of the ext_cp operands.
1275 // Used in RedefineClasses for CP merge.
1276 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1277 int delta_len = operand_array_length(ext_cp->operands());
1278 if (delta_len == 0) {
1279 return; // nothing to do
1280 }
1281 int delta_size = ext_cp->operands()->length();
1282
1283 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1284
1285 if (operand_array_length(operands()) == 0) {
1286 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1287 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1288 // The first element index defines the offset of second part
1289 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1290 set_operands(new_ops);
1291 } else {
1292 resize_operands(delta_len, delta_size, CHECK);
1293 }
1294
1295 } // end extend_operands()
1296
1297
1298 // Shrink the operands array to a smaller array with new_len length.
1299 // Used in RedefineClasses for CP merge.
1300 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1301 int old_len = operand_array_length(operands());
1302 if (new_len == old_len) {
1303 return; // nothing to do
1304 }
1305 assert(new_len < old_len, "shrunken operands array must be smaller");
1306
1307 int free_base = operand_next_offset_at(new_len - 1);
1308 int delta_len = new_len - old_len;
1309 int delta_size = 2*delta_len + free_base - operands()->length();
1310
1311 resize_operands(delta_len, delta_size, CHECK);
1312
1313 } // end shrink_operands()
1314
1315
1316 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1317 const constantPoolHandle& to_cp,
1318 TRAPS) {
1319
1320 int from_oplen = operand_array_length(from_cp->operands());
1321 int old_oplen = operand_array_length(to_cp->operands());
1322 if (from_oplen != 0) {
1323 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1324 // append my operands to the target's operands array
1325 if (old_oplen == 0) {
1326 // Can't just reuse from_cp's operand list because of deallocation issues
1327 int len = from_cp->operands()->length();
1328 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1329 Copy::conjoint_memory_atomic(
1330 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1331 to_cp->set_operands(new_ops);
1332 } else {
1333 int old_len = to_cp->operands()->length();
1334 int from_len = from_cp->operands()->length();
1335 int old_off = old_oplen * sizeof(u2);
1336 int from_off = from_oplen * sizeof(u2);
1337 // Use the metaspace for the destination constant pool
1338 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1339 int fillp = 0, len = 0;
1340 // first part of dest
1341 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1342 new_operands->adr_at(fillp),
1343 (len = old_off) * sizeof(u2));
1344 fillp += len;
1345 // first part of src
1346 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1347 new_operands->adr_at(fillp),
1348 (len = from_off) * sizeof(u2));
1349 fillp += len;
1350 // second part of dest
1351 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1352 new_operands->adr_at(fillp),
1353 (len = old_len - old_off) * sizeof(u2));
1354 fillp += len;
1355 // second part of src
1356 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1357 new_operands->adr_at(fillp),
1358 (len = from_len - from_off) * sizeof(u2));
1359 fillp += len;
1360 assert(fillp == new_operands->length(), "");
1361
1362 // Adjust indexes in the first part of the copied operands array.
1363 for (int j = 0; j < from_oplen; j++) {
1364 int offset = operand_offset_at(new_operands, old_oplen + j);
1365 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1366 offset += old_len; // every new tuple is preceded by old_len extra u2's
1367 operand_offset_at_put(new_operands, old_oplen + j, offset);
1368 }
1369
1370 // replace target operands array with combined array
1371 to_cp->set_operands(new_operands);
1372 }
1373 }
1374 } // end copy_operands()
1375
1376
1377 // Copy this constant pool's entries at start_i to end_i (inclusive)
1378 // to the constant pool to_cp's entries starting at to_i. A total of
1379 // (end_i - start_i) + 1 entries are copied.
1380 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1381 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1382
1383
1384 int dest_i = to_i; // leave original alone for debug purposes
1385
1386 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1387 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1388
1389 switch (from_cp->tag_at(src_i).value()) {
1390 case JVM_CONSTANT_Double:
1391 case JVM_CONSTANT_Long:
1392 // double and long take two constant pool entries
1393 src_i += 2;
1394 dest_i += 2;
1395 break;
1396
1397 default:
1398 // all others take one constant pool entry
1399 src_i++;
1400 dest_i++;
1401 break;
1402 }
1403 }
1404 copy_operands(from_cp, to_cp, CHECK);
1405
1406 } // end copy_cp_to_impl()
1407
1408
1409 // Copy this constant pool's entry at from_i to the constant pool
1410 // to_cp's entry at to_i.
1411 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1412 const constantPoolHandle& to_cp, int to_i,
1413 TRAPS) {
1414
1415 int tag = from_cp->tag_at(from_i).value();
1416 switch (tag) {
1417 case JVM_CONSTANT_ClassIndex:
1418 {
1419 jint ki = from_cp->klass_index_at(from_i);
1420 to_cp->klass_index_at_put(to_i, ki);
1421 } break;
1422
1423 case JVM_CONSTANT_Double:
1424 {
1425 jdouble d = from_cp->double_at(from_i);
1426 to_cp->double_at_put(to_i, d);
1427 // double takes two constant pool entries so init second entry's tag
1428 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1429 } break;
1430
1431 case JVM_CONSTANT_Fieldref:
1432 {
1433 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1434 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1435 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1436 } break;
1437
1438 case JVM_CONSTANT_Float:
1439 {
1440 jfloat f = from_cp->float_at(from_i);
1441 to_cp->float_at_put(to_i, f);
1442 } break;
1443
1444 case JVM_CONSTANT_Integer:
1445 {
1446 jint i = from_cp->int_at(from_i);
1447 to_cp->int_at_put(to_i, i);
1448 } break;
1449
1450 case JVM_CONSTANT_InterfaceMethodref:
1451 {
1452 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1453 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1454 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1455 } break;
1456
1457 case JVM_CONSTANT_Long:
1458 {
1459 jlong l = from_cp->long_at(from_i);
1460 to_cp->long_at_put(to_i, l);
1461 // long takes two constant pool entries so init second entry's tag
1462 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1463 } break;
1464
1465 case JVM_CONSTANT_Methodref:
1466 {
1467 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1468 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1469 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1470 } break;
1471
1472 case JVM_CONSTANT_NameAndType:
1473 {
1474 int name_ref_index = from_cp->name_ref_index_at(from_i);
1475 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1476 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1477 } break;
1478
1479 case JVM_CONSTANT_StringIndex:
1480 {
1481 jint si = from_cp->string_index_at(from_i);
1482 to_cp->string_index_at_put(to_i, si);
1483 } break;
1484
1485 case JVM_CONSTANT_Class:
1486 case JVM_CONSTANT_UnresolvedClass:
1487 case JVM_CONSTANT_UnresolvedClassInError:
1488 {
1489 // Revert to JVM_CONSTANT_ClassIndex
1490 int name_index = from_cp->klass_slot_at(from_i).name_index();
1491 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1492 to_cp->klass_index_at_put(to_i, name_index);
1493 } break;
1494
1495 case JVM_CONSTANT_String:
1496 {
1497 Symbol* s = from_cp->unresolved_string_at(from_i);
1498 to_cp->unresolved_string_at_put(to_i, s);
1499 } break;
1500
1501 case JVM_CONSTANT_Utf8:
1502 {
1503 Symbol* s = from_cp->symbol_at(from_i);
1504 // Need to increase refcount, the old one will be thrown away and deferenced
1505 s->increment_refcount();
1506 to_cp->symbol_at_put(to_i, s);
1507 } break;
1508
1509 case JVM_CONSTANT_MethodType:
1510 case JVM_CONSTANT_MethodTypeInError:
1511 {
1512 jint k = from_cp->method_type_index_at(from_i);
1513 to_cp->method_type_index_at_put(to_i, k);
1514 } break;
1515
1516 case JVM_CONSTANT_MethodHandle:
1517 case JVM_CONSTANT_MethodHandleInError:
1518 {
1519 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1520 int k2 = from_cp->method_handle_index_at(from_i);
1521 to_cp->method_handle_index_at_put(to_i, k1, k2);
1522 } break;
1523
1524 case JVM_CONSTANT_InvokeDynamic:
1525 {
1526 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1527 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1528 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1529 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1530 } break;
1531
1532 // Invalid is used as the tag for the second constant pool entry
1533 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1534 // not be seen by itself.
1535 case JVM_CONSTANT_Invalid: // fall through
1536
1537 default:
1538 {
1539 ShouldNotReachHere();
1540 } break;
1541 }
1542 } // end copy_entry_to()
1543
1544 // Search constant pool search_cp for an entry that matches this
1545 // constant pool's entry at pattern_i. Returns the index of a
1546 // matching entry or zero (0) if there is no matching entry.
1547 int ConstantPool::find_matching_entry(int pattern_i,
1548 const constantPoolHandle& search_cp, TRAPS) {
1549
1550 // index zero (0) is not used
1551 for (int i = 1; i < search_cp->length(); i++) {
1552 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1553 if (found) {
1554 return i;
1555 }
1556 }
1557
1558 return 0; // entry not found; return unused index zero (0)
1559 } // end find_matching_entry()
1560
1561
1562 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1563 // cp2's bootstrap specifier at idx2.
1564 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1565 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1566 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1567 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1568
1569 if (!match) {
1570 return false;
1571 }
1572 int argc = operand_argument_count_at(idx1);
1573 if (argc == cp2->operand_argument_count_at(idx2)) {
1574 for (int j = 0; j < argc; j++) {
1575 k1 = operand_argument_index_at(idx1, j);
1576 k2 = cp2->operand_argument_index_at(idx2, j);
1577 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1578 if (!match) {
1579 return false;
1580 }
1581 }
1582 return true; // got through loop; all elements equal
1583 }
1584 return false;
1585 } // end compare_operand_to()
1586
1587 // Search constant pool search_cp for a bootstrap specifier that matches
1588 // this constant pool's bootstrap specifier at pattern_i index.
1589 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1590 int ConstantPool::find_matching_operand(int pattern_i,
1591 const constantPoolHandle& search_cp, int search_len, TRAPS) {
1592 for (int i = 0; i < search_len; i++) {
1593 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1594 if (found) {
1595 return i;
1596 }
1597 }
1598 return -1; // bootstrap specifier not found; return unused index (-1)
1599 } // end find_matching_operand()
1600
1601
1602 #ifndef PRODUCT
1603
1604 const char* ConstantPool::printable_name_at(int which) {
1605
1606 constantTag tag = tag_at(which);
1607
1608 if (tag.is_string()) {
1609 return string_at_noresolve(which);
1610 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1611 return klass_name_at(which)->as_C_string();
1612 } else if (tag.is_symbol()) {
1613 return symbol_at(which)->as_C_string();
1614 }
1615 return "";
1616 }
1617
1618 #endif // PRODUCT
1619
1620
1621 // JVMTI GetConstantPool support
1622
1623 // For debugging of constant pool
1624 const bool debug_cpool = false;
1625
1626 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1627
1628 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1629 const char* WARN_MSG = "Must not be such entry!";
1630 jint size = 0;
1631 u2 idx1, idx2;
1632
1633 for (jint idx = 1; idx < cnt; idx++) {
1634 jint ent_size = 0;
1635 u1 tag = *bytes++;
1636 size++; // count tag
1637
1638 printf("const #%03d, tag: %02d ", idx, tag);
1639 switch(tag) {
1640 case JVM_CONSTANT_Invalid: {
1641 printf("Invalid");
1642 break;
1643 }
1644 case JVM_CONSTANT_Unicode: {
1645 printf("Unicode %s", WARN_MSG);
1646 break;
1647 }
1648 case JVM_CONSTANT_Utf8: {
1649 u2 len = Bytes::get_Java_u2(bytes);
1650 char str[128];
1651 if (len > 127) {
1652 len = 127;
1653 }
1654 strncpy(str, (char *) (bytes+2), len);
1655 str[len] = '\0';
1656 printf("Utf8 \"%s\"", str);
1657 ent_size = 2 + len;
1658 break;
1659 }
1660 case JVM_CONSTANT_Integer: {
1661 u4 val = Bytes::get_Java_u4(bytes);
1662 printf("int %d", *(int *) &val);
1663 ent_size = 4;
1664 break;
1665 }
1666 case JVM_CONSTANT_Float: {
1667 u4 val = Bytes::get_Java_u4(bytes);
1668 printf("float %5.3ff", *(float *) &val);
1669 ent_size = 4;
1670 break;
1671 }
1672 case JVM_CONSTANT_Long: {
1673 u8 val = Bytes::get_Java_u8(bytes);
1674 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1675 ent_size = 8;
1676 idx++; // Long takes two cpool slots
1677 break;
1678 }
1679 case JVM_CONSTANT_Double: {
1680 u8 val = Bytes::get_Java_u8(bytes);
1681 printf("double %5.3fd", *(jdouble *)&val);
1682 ent_size = 8;
1683 idx++; // Double takes two cpool slots
1684 break;
1685 }
1686 case JVM_CONSTANT_Class: {
1687 idx1 = Bytes::get_Java_u2(bytes);
1688 printf("class #%03d", idx1);
1689 ent_size = 2;
1690 break;
1691 }
1692 case JVM_CONSTANT_String: {
1693 idx1 = Bytes::get_Java_u2(bytes);
1694 printf("String #%03d", idx1);
1695 ent_size = 2;
1696 break;
1697 }
1698 case JVM_CONSTANT_Fieldref: {
1699 idx1 = Bytes::get_Java_u2(bytes);
1700 idx2 = Bytes::get_Java_u2(bytes+2);
1701 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1702 ent_size = 4;
1703 break;
1704 }
1705 case JVM_CONSTANT_Methodref: {
1706 idx1 = Bytes::get_Java_u2(bytes);
1707 idx2 = Bytes::get_Java_u2(bytes+2);
1708 printf("Method #%03d, #%03d", idx1, idx2);
1709 ent_size = 4;
1710 break;
1711 }
1712 case JVM_CONSTANT_InterfaceMethodref: {
1713 idx1 = Bytes::get_Java_u2(bytes);
1714 idx2 = Bytes::get_Java_u2(bytes+2);
1715 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1716 ent_size = 4;
1717 break;
1718 }
1719 case JVM_CONSTANT_NameAndType: {
1720 idx1 = Bytes::get_Java_u2(bytes);
1721 idx2 = Bytes::get_Java_u2(bytes+2);
1722 printf("NameAndType #%03d, #%03d", idx1, idx2);
1723 ent_size = 4;
1724 break;
1725 }
1726 case JVM_CONSTANT_ClassIndex: {
1727 printf("ClassIndex %s", WARN_MSG);
1728 break;
1729 }
1730 case JVM_CONSTANT_UnresolvedClass: {
1731 printf("UnresolvedClass: %s", WARN_MSG);
1732 break;
1733 }
1734 case JVM_CONSTANT_UnresolvedClassInError: {
1735 printf("UnresolvedClassInErr: %s", WARN_MSG);
1736 break;
1737 }
1738 case JVM_CONSTANT_StringIndex: {
1739 printf("StringIndex: %s", WARN_MSG);
1740 break;
1741 }
1742 }
1743 printf(";\n");
1744 bytes += ent_size;
1745 size += ent_size;
1746 }
1747 printf("Cpool size: %d\n", size);
1748 fflush(0);
1749 return;
1750 } /* end print_cpool_bytes */
1751
1752
1753 // Returns size of constant pool entry.
1754 jint ConstantPool::cpool_entry_size(jint idx) {
1755 switch(tag_at(idx).value()) {
1756 case JVM_CONSTANT_Invalid:
1757 case JVM_CONSTANT_Unicode:
1758 return 1;
1759
1760 case JVM_CONSTANT_Utf8:
1761 return 3 + symbol_at(idx)->utf8_length();
1762
1763 case JVM_CONSTANT_Class:
1764 case JVM_CONSTANT_String:
1765 case JVM_CONSTANT_ClassIndex:
1766 case JVM_CONSTANT_UnresolvedClass:
1767 case JVM_CONSTANT_UnresolvedClassInError:
1768 case JVM_CONSTANT_StringIndex:
1769 case JVM_CONSTANT_MethodType:
1770 case JVM_CONSTANT_MethodTypeInError:
1771 return 3;
1772
1773 case JVM_CONSTANT_MethodHandle:
1774 case JVM_CONSTANT_MethodHandleInError:
1775 return 4; //tag, ref_kind, ref_index
1776
1777 case JVM_CONSTANT_Integer:
1778 case JVM_CONSTANT_Float:
1779 case JVM_CONSTANT_Fieldref:
1780 case JVM_CONSTANT_Methodref:
1781 case JVM_CONSTANT_InterfaceMethodref:
1782 case JVM_CONSTANT_NameAndType:
1783 return 5;
1784
1785 case JVM_CONSTANT_InvokeDynamic:
1786 // u1 tag, u2 bsm, u2 nt
1787 return 5;
1788
1789 case JVM_CONSTANT_Long:
1790 case JVM_CONSTANT_Double:
1791 return 9;
1792 }
1793 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1794 return 1;
1795 } /* end cpool_entry_size */
1796
1797
1798 // SymbolHashMap is used to find a constant pool index from a string.
1799 // This function fills in SymbolHashMaps, one for utf8s and one for
1800 // class names, returns size of the cpool raw bytes.
1801 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1802 SymbolHashMap *classmap) {
1803 jint size = 0;
1804
1805 for (u2 idx = 1; idx < length(); idx++) {
1806 u2 tag = tag_at(idx).value();
1807 size += cpool_entry_size(idx);
1808
1809 switch(tag) {
1810 case JVM_CONSTANT_Utf8: {
1811 Symbol* sym = symbol_at(idx);
1812 symmap->add_entry(sym, idx);
1813 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1814 break;
1815 }
1816 case JVM_CONSTANT_Class:
1817 case JVM_CONSTANT_UnresolvedClass:
1818 case JVM_CONSTANT_UnresolvedClassInError: {
1819 Symbol* sym = klass_name_at(idx);
1820 classmap->add_entry(sym, idx);
1821 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1822 break;
1823 }
1824 case JVM_CONSTANT_Long:
1825 case JVM_CONSTANT_Double: {
1826 idx++; // Both Long and Double take two cpool slots
1827 break;
1828 }
1829 }
1830 }
1831 return size;
1832 } /* end hash_utf8_entries_to */
1833
1834
1835 // Copy cpool bytes.
1836 // Returns:
1837 // 0, in case of OutOfMemoryError
1838 // -1, in case of internal error
1839 // > 0, count of the raw cpool bytes that have been copied
1840 int ConstantPool::copy_cpool_bytes(int cpool_size,
1841 SymbolHashMap* tbl,
1842 unsigned char *bytes) {
1843 u2 idx1, idx2;
1844 jint size = 0;
1845 jint cnt = length();
1846 unsigned char *start_bytes = bytes;
1847
1848 for (jint idx = 1; idx < cnt; idx++) {
1849 u1 tag = tag_at(idx).value();
1850 jint ent_size = cpool_entry_size(idx);
1851
1852 assert(size + ent_size <= cpool_size, "Size mismatch");
1853
1854 *bytes = tag;
1855 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
1856 switch(tag) {
1857 case JVM_CONSTANT_Invalid: {
1858 DBG(printf("JVM_CONSTANT_Invalid"));
1859 break;
1860 }
1861 case JVM_CONSTANT_Unicode: {
1862 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1863 DBG(printf("JVM_CONSTANT_Unicode"));
1864 break;
1865 }
1866 case JVM_CONSTANT_Utf8: {
1867 Symbol* sym = symbol_at(idx);
1868 char* str = sym->as_utf8();
1869 // Warning! It's crashing on x86 with len = sym->utf8_length()
1870 int len = (int) strlen(str);
1871 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1872 for (int i = 0; i < len; i++) {
1873 bytes[3+i] = (u1) str[i];
1874 }
1875 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1876 break;
1877 }
1878 case JVM_CONSTANT_Integer: {
1879 jint val = int_at(idx);
1880 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1881 break;
1882 }
1883 case JVM_CONSTANT_Float: {
1884 jfloat val = float_at(idx);
1885 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1886 break;
1887 }
1888 case JVM_CONSTANT_Long: {
1889 jlong val = long_at(idx);
1890 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1891 idx++; // Long takes two cpool slots
1892 break;
1893 }
1894 case JVM_CONSTANT_Double: {
1895 jdouble val = double_at(idx);
1896 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1897 idx++; // Double takes two cpool slots
1898 break;
1899 }
1900 case JVM_CONSTANT_Class:
1901 case JVM_CONSTANT_UnresolvedClass:
1902 case JVM_CONSTANT_UnresolvedClassInError: {
1903 *bytes = JVM_CONSTANT_Class;
1904 Symbol* sym = klass_name_at(idx);
1905 idx1 = tbl->symbol_to_value(sym);
1906 assert(idx1 != 0, "Have not found a hashtable entry");
1907 Bytes::put_Java_u2((address) (bytes+1), idx1);
1908 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1909 break;
1910 }
1911 case JVM_CONSTANT_String: {
1912 *bytes = JVM_CONSTANT_String;
1913 Symbol* sym = unresolved_string_at(idx);
1914 idx1 = tbl->symbol_to_value(sym);
1915 assert(idx1 != 0, "Have not found a hashtable entry");
1916 Bytes::put_Java_u2((address) (bytes+1), idx1);
1917 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1918 break;
1919 }
1920 case JVM_CONSTANT_Fieldref:
1921 case JVM_CONSTANT_Methodref:
1922 case JVM_CONSTANT_InterfaceMethodref: {
1923 idx1 = uncached_klass_ref_index_at(idx);
1924 idx2 = uncached_name_and_type_ref_index_at(idx);
1925 Bytes::put_Java_u2((address) (bytes+1), idx1);
1926 Bytes::put_Java_u2((address) (bytes+3), idx2);
1927 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1928 break;
1929 }
1930 case JVM_CONSTANT_NameAndType: {
1931 idx1 = name_ref_index_at(idx);
1932 idx2 = signature_ref_index_at(idx);
1933 Bytes::put_Java_u2((address) (bytes+1), idx1);
1934 Bytes::put_Java_u2((address) (bytes+3), idx2);
1935 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1936 break;
1937 }
1938 case JVM_CONSTANT_ClassIndex: {
1939 *bytes = JVM_CONSTANT_Class;
1940 idx1 = klass_index_at(idx);
1941 Bytes::put_Java_u2((address) (bytes+1), idx1);
1942 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1943 break;
1944 }
1945 case JVM_CONSTANT_StringIndex: {
1946 *bytes = JVM_CONSTANT_String;
1947 idx1 = string_index_at(idx);
1948 Bytes::put_Java_u2((address) (bytes+1), idx1);
1949 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1950 break;
1951 }
1952 case JVM_CONSTANT_MethodHandle:
1953 case JVM_CONSTANT_MethodHandleInError: {
1954 *bytes = JVM_CONSTANT_MethodHandle;
1955 int kind = method_handle_ref_kind_at(idx);
1956 idx1 = method_handle_index_at(idx);
1957 *(bytes+1) = (unsigned char) kind;
1958 Bytes::put_Java_u2((address) (bytes+2), idx1);
1959 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1960 break;
1961 }
1962 case JVM_CONSTANT_MethodType:
1963 case JVM_CONSTANT_MethodTypeInError: {
1964 *bytes = JVM_CONSTANT_MethodType;
1965 idx1 = method_type_index_at(idx);
1966 Bytes::put_Java_u2((address) (bytes+1), idx1);
1967 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1968 break;
1969 }
1970 case JVM_CONSTANT_InvokeDynamic: {
1971 *bytes = tag;
1972 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1973 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1974 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1975 Bytes::put_Java_u2((address) (bytes+1), idx1);
1976 Bytes::put_Java_u2((address) (bytes+3), idx2);
1977 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1978 break;
1979 }
1980 }
1981 DBG(printf("\n"));
1982 bytes += ent_size;
1983 size += ent_size;
1984 }
1985 assert(size == cpool_size, "Size mismatch");
1986
1987 // Keep temorarily for debugging until it's stable.
1988 DBG(print_cpool_bytes(cnt, start_bytes));
1989 return (int)(bytes - start_bytes);
1990 } /* end copy_cpool_bytes */
1991
1992 #undef DBG
1993
1994
1995 void ConstantPool::set_on_stack(const bool value) {
1996 if (value) {
1997 // Only record if it's not already set.
1998 if (!on_stack()) {
1999 assert(!is_shared(), "should always be set for shared constant pools");
2000 _flags |= _on_stack;
2001 MetadataOnStackMark::record(this);
2002 }
2003 } else {
2004 // Clearing is done single-threadedly.
2005 if (!is_shared()) {
2006 _flags &= ~_on_stack;
2007 }
2008 }
2009 }
2010
2011 // JSR 292 support for patching constant pool oops after the class is linked and
2012 // the oop array for resolved references are created.
2013 // We can't do this during classfile parsing, which is how the other indexes are
2014 // patched. The other patches are applied early for some error checking
2015 // so only defer the pseudo_strings.
2016 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
2017 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
2018 Handle patch = cp_patches->at(index);
2019 if (patch.not_null()) {
2020 assert (tag_at(index).is_string(), "should only be string left");
2021 // Patching a string means pre-resolving it.
2022 // The spelling in the constant pool is ignored.
2023 // The constant reference may be any object whatever.
2024 // If it is not a real interned string, the constant is referred
2025 // to as a "pseudo-string", and must be presented to the CP
2026 // explicitly, because it may require scavenging.
2027 int obj_index = cp_to_object_index(index);
2028 pseudo_string_at_put(index, obj_index, patch());
2029 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
2030 }
2031 }
2032 #ifdef ASSERT
2033 // Ensure that all the patches have been used.
2034 for (int index = 0; index < cp_patches->length(); index++) {
2035 assert(cp_patches->at(index).is_null(),
2036 "Unused constant pool patch at %d in class file %s",
2037 index,
2038 pool_holder()->external_name());
2039 }
2040 #endif // ASSERT
2041 }
2042
2043 #ifndef PRODUCT
2044
2045 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
2046 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
2047 guarantee(obj->is_constantPool(), "object must be constant pool");
2048 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
2049 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
2050
2051 for (int i = 0; i< cp->length(); i++) {
2052 if (cp->tag_at(i).is_unresolved_klass()) {
2053 // This will force loading of the class
2054 Klass* klass = cp->klass_at(i, CHECK);
2055 if (klass->is_instance_klass()) {
2056 // Force initialization of class
2057 InstanceKlass::cast(klass)->initialize(CHECK);
2058 }
2059 }
2060 }
2061 }
2062
2063 #endif
2064
2065
2066 // Printing
2067
2068 void ConstantPool::print_on(outputStream* st) const {
2069 assert(is_constantPool(), "must be constantPool");
2070 st->print_cr("%s", internal_name());
2071 if (flags() != 0) {
2072 st->print(" - flags: 0x%x", flags());
2073 if (has_preresolution()) st->print(" has_preresolution");
2074 if (on_stack()) st->print(" on_stack");
2075 st->cr();
2076 }
2077 if (pool_holder() != NULL) {
2078 st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
2079 }
2080 st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
2081 st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
2082 st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
2083 st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
2084
2085 for (int index = 1; index < length(); index++) { // Index 0 is unused
2086 ((ConstantPool*)this)->print_entry_on(index, st);
2087 switch (tag_at(index).value()) {
2088 case JVM_CONSTANT_Long :
2089 case JVM_CONSTANT_Double :
2090 index++; // Skip entry following eigth-byte constant
2091 }
2092
2093 }
2094 st->cr();
2095 }
2096
2097 // Print one constant pool entry
2098 void ConstantPool::print_entry_on(const int index, outputStream* st) {
2099 EXCEPTION_MARK;
2100 st->print(" - %3d : ", index);
2101 tag_at(index).print_on(st);
2102 st->print(" : ");
2103 switch (tag_at(index).value()) {
2104 case JVM_CONSTANT_Class :
2105 { Klass* k = klass_at(index, CATCH);
2106 guarantee(k != NULL, "need klass");
2107 k->print_value_on(st);
2108 st->print(" {" PTR_FORMAT "}", p2i(k));
2109 }
2110 break;
2111 case JVM_CONSTANT_Fieldref :
2112 case JVM_CONSTANT_Methodref :
2113 case JVM_CONSTANT_InterfaceMethodref :
2114 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
2115 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
2116 break;
2117 case JVM_CONSTANT_String :
2118 if (is_pseudo_string_at(index)) {
2119 oop anObj = pseudo_string_at(index);
2120 anObj->print_value_on(st);
2121 st->print(" {" PTR_FORMAT "}", p2i(anObj));
2122 } else {
2123 unresolved_string_at(index)->print_value_on(st);
2124 }
2125 break;
2126 case JVM_CONSTANT_Integer :
2127 st->print("%d", int_at(index));
2128 break;
2129 case JVM_CONSTANT_Float :
2130 st->print("%f", float_at(index));
2131 break;
2132 case JVM_CONSTANT_Long :
2133 st->print_jlong(long_at(index));
2134 break;
2135 case JVM_CONSTANT_Double :
2136 st->print("%lf", double_at(index));
2137 break;
2138 case JVM_CONSTANT_NameAndType :
2139 st->print("name_index=%d", name_ref_index_at(index));
2140 st->print(" signature_index=%d", signature_ref_index_at(index));
2141 break;
2142 case JVM_CONSTANT_Utf8 :
2143 symbol_at(index)->print_value_on(st);
2144 break;
2145 case JVM_CONSTANT_ClassIndex: {
2146 int name_index = *int_at_addr(index);
2147 st->print("klass_index=%d ", name_index);
2148 symbol_at(name_index)->print_value_on(st);
2149 }
2150 break;
2151 case JVM_CONSTANT_UnresolvedClass : // fall-through
2152 case JVM_CONSTANT_UnresolvedClassInError: {
2153 CPKlassSlot kslot = klass_slot_at(index);
2154 int resolved_klass_index = kslot.resolved_klass_index();
2155 int name_index = kslot.name_index();
2156 assert(tag_at(name_index).is_symbol(), "sanity");
2157
2158 Klass* klass = resolved_klasses()->at(resolved_klass_index);
2159 if (klass != NULL) {
2160 klass->print_value_on(st);
2161 } else {
2162 symbol_at(name_index)->print_value_on(st);
2163 }
2164 }
2165 break;
2166 case JVM_CONSTANT_MethodHandle :
2167 case JVM_CONSTANT_MethodHandleInError :
2168 st->print("ref_kind=%d", method_handle_ref_kind_at(index));
2169 st->print(" ref_index=%d", method_handle_index_at(index));
2170 break;
2171 case JVM_CONSTANT_MethodType :
2172 case JVM_CONSTANT_MethodTypeInError :
2173 st->print("signature_index=%d", method_type_index_at(index));
2174 break;
2175 case JVM_CONSTANT_InvokeDynamic :
2176 {
2177 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2178 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2179 int argc = invoke_dynamic_argument_count_at(index);
2180 if (argc > 0) {
2181 for (int arg_i = 0; arg_i < argc; arg_i++) {
2182 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2183 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2184 }
2185 st->print("}");
2186 }
2187 }
2188 break;
2189 default:
2190 ShouldNotReachHere();
2191 break;
2192 }
2193 st->cr();
2194 }
2195
2196 void ConstantPool::print_value_on(outputStream* st) const {
2197 assert(is_constantPool(), "must be constantPool");
2198 st->print("constant pool [%d]", length());
2199 if (has_preresolution()) st->print("/preresolution");
2200 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2201 print_address_on(st);
2202 st->print(" for ");
2203 pool_holder()->print_value_on(st);
2204 if (pool_holder() != NULL) {
2205 bool extra = (pool_holder()->constants() != this);
2206 if (extra) st->print(" (extra)");
2207 }
2208 if (cache() != NULL) {
2209 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2210 }
2211 }
2212
2213 #if INCLUDE_SERVICES
2214 // Size Statistics
2215 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2216 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2217 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2218 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2219 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2220 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2221
2222 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2223 sz->_cp_refmap_bytes;
2224 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2225 }
2226 #endif // INCLUDE_SERVICES
2227
2228 // Verification
2229
2230 void ConstantPool::verify_on(outputStream* st) {
2231 guarantee(is_constantPool(), "object must be constant pool");
2232 for (int i = 0; i< length(); i++) {
2233 constantTag tag = tag_at(i);
2234 if (tag.is_klass() || tag.is_unresolved_klass()) {
2235 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2236 } else if (tag.is_symbol()) {
2237 CPSlot entry = slot_at(i);
2238 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2239 } else if (tag.is_string()) {
2240 CPSlot entry = slot_at(i);
2241 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2242 }
2243 }
2244 if (cache() != NULL) {
2245 // Note: cache() can be NULL before a class is completely setup or
2246 // in temporary constant pools used during constant pool merging
2247 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2248 }
2249 if (pool_holder() != NULL) {
2250 // Note: pool_holder() can be NULL in temporary constant pools
2251 // used during constant pool merging
2252 guarantee(pool_holder()->is_klass(), "should be klass");
2253 }
2254 }
2255
2256
2257 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2258 char *str = sym->as_utf8();
2259 unsigned int hash = compute_hash(str, sym->utf8_length());
2260 unsigned int index = hash % table_size();
2261
2262 // check if already in map
2263 // we prefer the first entry since it is more likely to be what was used in
2264 // the class file
2265 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2266 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2267 if (en->hash() == hash && en->symbol() == sym) {
2268 return; // already there
2269 }
2270 }
2271
2272 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2273 entry->set_next(bucket(index));
2274 _buckets[index].set_entry(entry);
2275 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2276 }
2277
2278 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2279 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2280 char *str = sym->as_utf8();
2281 int len = sym->utf8_length();
2282 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2283 unsigned int index = hash % table_size();
2284 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2285 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2286 if (en->hash() == hash && en->symbol() == sym) {
2287 return en;
2288 }
2289 }
2290 return NULL;
2291 }