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
288 bool ConstantPool::resolve_class_constants(TRAPS) {
289 assert(DumpSharedSpaces, "used during dump time only");
290 // The _cache may be NULL if the _pool_holder klass fails verification
291 // at dump time due to missing dependencies.
292 if (cache() == NULL || reference_map() == NULL) {
293 return true; // nothing to do
294 }
295
296 constantPoolHandle cp(THREAD, this);
297 for (int index = 1; index < length(); index++) { // Index 0 is unused
298 if (tag_at(index).is_string()) {
299 Symbol* sym = cp->unresolved_string_at(index);
300 // Look up only. Only resolve references to already interned strings.
301 oop str = StringTable::lookup(sym);
302 if (str != NULL) {
303 int cache_index = cp->cp_to_object_index(index);
304 cp->string_at_put(index, cache_index, str);
305 }
306 }
307 }
308 return true;
309 }
310 #endif
311
312 // CDS support. Create a new resolved_references array.
313 void ConstantPool::restore_unshareable_info(TRAPS) {
314 assert(is_constantPool(), "ensure C++ vtable is restored");
315 assert(on_stack(), "should always be set for shared constant pools");
316 assert(is_shared(), "should always be set for shared constant pools");
317 assert(_cache != NULL, "constant pool _cache should not be NULL");
318
319 // Only create the new resolved references array if it hasn't been attempted before
320 if (resolved_references() != NULL) return;
321
322 // restore the C++ vtable from the shared archive
323 restore_vtable();
324
325 if (SystemDictionary::Object_klass_loaded()) {
326 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
327 #if INCLUDE_CDS_JAVA_HEAP
328 if (MetaspaceShared::open_archive_heap_region_mapped() &&
329 _cache->archived_references() != NULL) {
330 oop archived = _cache->archived_references();
331 // Make sure GC knows the cached object is now live. This is necessary after
332 // initial GC marking and during concurrent marking as strong roots are only
333 // scanned during initial marking (at the start of the GC marking).
334 assert(UseG1GC, "Requires G1 GC");
335 G1SATBCardTableModRefBS::enqueue(archived);
336 // Create handle for the archived resolved reference array object
337 Handle refs_handle(THREAD, (oop)archived);
338 set_resolved_references(loader_data->add_handle(refs_handle));
339 } else
340 #endif
341 {
342 // No mapped archived resolved reference array
343 // Recreate the object array and add to ClassLoaderData.
344 int map_length = resolved_reference_length();
345 if (map_length > 0) {
346 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
347 Handle refs_handle(THREAD, (oop)stom); // must handleize.
348 set_resolved_references(loader_data->add_handle(refs_handle));
349 }
350 }
351 }
352 }
353
354 void ConstantPool::remove_unshareable_info() {
355 // Resolved references are not in the shared archive.
356 // Save the length for restoration. It is not necessarily the same length
357 // as reference_map.length() if invokedynamic is saved. It is needed when
358 // re-creating the resolved reference array if archived heap data cannot be map
359 // at runtime.
360 set_resolved_reference_length(
361 resolved_references() != NULL ? resolved_references()->length() : 0);
362
363 // If archiving heap objects is not allowed, clear the resolved references.
364 // Otherwise, it is cleared after the resolved references array is cached
365 // (see archive_resolved_references()).
366 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
367 set_resolved_references(NULL);
368 }
369
370 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
371 // The _on_stack flag is used to prevent ConstantPools from deallocation during
372 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
373 // we always set _on_stack to true to avoid having to change _flags during runtime.
374 _flags |= (_on_stack | _is_shared);
375 int num_klasses = 0;
376 for (int index = 1; index < length(); index++) { // Index 0 is unused
377 assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
378 if (tag_at(index).is_klass()) {
379 // This class was resolved as a side effect of executing Java code
380 // during dump time. We need to restore it back to an UnresolvedClass,
381 // so that the proper class loading and initialization can happen
382 // at runtime.
383 CPKlassSlot kslot = klass_slot_at(index);
384 int resolved_klass_index = kslot.resolved_klass_index();
385 int name_index = kslot.name_index();
386 assert(tag_at(name_index).is_symbol(), "sanity");
387 resolved_klasses()->at_put(resolved_klass_index, NULL);
388 tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
389 assert(klass_name_at(index) == symbol_at(name_index), "sanity");
390 }
391 }
392 if (cache() != NULL) {
393 cache()->remove_unshareable_info();
394 }
395 }
396
397 int ConstantPool::cp_to_object_index(int cp_index) {
398 // this is harder don't do this so much.
399 int i = reference_map()->find(cp_index);
400 // We might not find the index for jsr292 call.
401 return (i < 0) ? _no_index_sentinel : i;
402 }
403
404 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
405 resolved_references()->obj_at_put(obj_index, str);
406 }
407
408 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
409 ResourceMark rm;
410 int line_number = -1;
411 const char * source_file = NULL;
412 if (JavaThread::current()->has_last_Java_frame()) {
413 // try to identify the method which called this function.
414 vframeStream vfst(JavaThread::current());
415 if (!vfst.at_end()) {
416 line_number = vfst.method()->line_number_from_bci(vfst.bci());
417 Symbol* s = vfst.method()->method_holder()->source_file_name();
418 if (s != NULL) {
419 source_file = s->as_C_string();
420 }
421 }
422 }
423 if (k != this_cp->pool_holder()) {
424 // only print something if the classes are different
425 if (source_file != NULL) {
426 log_debug(class, resolve)("%s %s %s:%d",
427 this_cp->pool_holder()->external_name(),
428 k->external_name(), source_file, line_number);
429 } else {
430 log_debug(class, resolve)("%s %s",
431 this_cp->pool_holder()->external_name(),
432 k->external_name());
433 }
434 }
435 }
436
437 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
438 bool save_resolution_error, TRAPS) {
439 assert(THREAD->is_Java_thread(), "must be a Java thread");
440
441 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
442 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
443 // the entry and tag is not updated atomicly.
444 CPKlassSlot kslot = this_cp->klass_slot_at(which);
445 int resolved_klass_index = kslot.resolved_klass_index();
446 int name_index = kslot.name_index();
447 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
448
449 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
450 if (klass != NULL) {
451 return klass;
452 }
453
454 // This tag doesn't change back to unresolved class unless at a safepoint.
455 if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
456 // The original attempt to resolve this constant pool entry failed so find the
457 // class of the original error and throw another error of the same class
458 // (JVMS 5.4.3).
459 // If there is a detail message, pass that detail message to the error.
460 // The JVMS does not strictly require us to duplicate the same detail message,
461 // or any internal exception fields such as cause or stacktrace. But since the
462 // detail message is often a class name or other literal string, we will repeat it
463 // if we can find it in the symbol table.
464 throw_resolution_error(this_cp, which, CHECK_0);
465 ShouldNotReachHere();
466 }
467
468 Handle mirror_handle;
469 Symbol* name = this_cp->symbol_at(name_index);
470 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
471 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
472 Klass* k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
473 if (!HAS_PENDING_EXCEPTION) {
474 // preserve the resolved klass from unloading
475 mirror_handle = Handle(THREAD, k->java_mirror());
476 // Do access check for klasses
477 verify_constant_pool_resolve(this_cp, k, THREAD);
478 }
479
480 // Failed to resolve class. We must record the errors so that subsequent attempts
481 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
482 if (HAS_PENDING_EXCEPTION) {
483 if (save_resolution_error) {
484 save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
485 // If CHECK_NULL above doesn't return the exception, that means that
486 // some other thread has beaten us and has resolved the class.
487 // To preserve old behavior, we return the resolved class.
488 klass = this_cp->resolved_klasses()->at(resolved_klass_index);
489 assert(klass != NULL, "must be resolved if exception was cleared");
490 return klass;
491 } else {
492 return NULL; // return the pending exception
493 }
494 }
495
496 // Make this class loader depend upon the class loader owning the class reference
497 ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
498 this_key->record_dependency(k, CHECK_NULL); // Can throw OOM
499
500 // logging for class+resolve.
501 if (log_is_enabled(Debug, class, resolve)){
502 trace_class_resolution(this_cp, k);
503 }
504 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
505 OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
506 // The interpreter assumes when the tag is stored, the klass is resolved
507 // and the Klass* stored in _resolved_klasses is non-NULL, so we need
508 // hardware store ordering here.
509 this_cp->release_tag_at_put(which, JVM_CONSTANT_Class);
510 return k;
511 }
512
513
514 // Does not update ConstantPool* - to avoid any exception throwing. Used
515 // by compiler and exception handling. Also used to avoid classloads for
516 // instanceof operations. Returns NULL if the class has not been loaded or
517 // if the verification of constant pool failed
518 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
519 CPKlassSlot kslot = this_cp->klass_slot_at(which);
520 int resolved_klass_index = kslot.resolved_klass_index();
521 int name_index = kslot.name_index();
522 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
523
524 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
525 if (k != NULL) {
526 return k;
527 } else {
528 Thread *thread = Thread::current();
529 Symbol* name = this_cp->symbol_at(name_index);
530 oop loader = this_cp->pool_holder()->class_loader();
531 oop protection_domain = this_cp->pool_holder()->protection_domain();
532 Handle h_prot (thread, protection_domain);
533 Handle h_loader (thread, loader);
534 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
535
536 if (k != NULL) {
537 // Make sure that resolving is legal
538 EXCEPTION_MARK;
539 // return NULL if verification fails
540 verify_constant_pool_resolve(this_cp, k, THREAD);
541 if (HAS_PENDING_EXCEPTION) {
542 CLEAR_PENDING_EXCEPTION;
543 return NULL;
544 }
545 return k;
546 } else {
547 return k;
548 }
549 }
550 }
551
552
553 Klass* ConstantPool::klass_ref_at_if_loaded(const constantPoolHandle& this_cp, int which) {
554 return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
555 }
556
557
558 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
559 int which) {
560 if (cpool->cache() == NULL) return NULL; // nothing to load yet
561 int cache_index = decode_cpcache_index(which, true);
562 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
563 // FIXME: should be an assert
564 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
565 return NULL;
566 }
567 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
568 return e->method_if_resolved(cpool);
569 }
570
571
572 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
573 if (cpool->cache() == NULL) return false; // nothing to load yet
574 int cache_index = decode_cpcache_index(which, true);
575 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
576 return e->has_appendix();
577 }
578
579 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
580 if (cpool->cache() == NULL) return NULL; // nothing to load yet
581 int cache_index = decode_cpcache_index(which, true);
582 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
583 return e->appendix_if_resolved(cpool);
584 }
585
586
587 bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
588 if (cpool->cache() == NULL) return false; // nothing to load yet
589 int cache_index = decode_cpcache_index(which, true);
590 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
591 return e->has_method_type();
592 }
593
594 oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
595 if (cpool->cache() == NULL) return NULL; // nothing to load yet
596 int cache_index = decode_cpcache_index(which, true);
597 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
598 return e->method_type_if_resolved(cpool);
599 }
600
601
602 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
603 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
604 return symbol_at(name_index);
605 }
606
607
608 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
609 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
610 return symbol_at(signature_index);
611 }
612
613
614 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
615 int i = which;
616 if (!uncached && cache() != NULL) {
617 if (ConstantPool::is_invokedynamic_index(which)) {
618 // Invokedynamic index is index into the constant pool cache
619 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
620 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
621 assert(tag_at(pool_index).is_name_and_type(), "");
622 return pool_index;
623 }
624 // change byte-ordering and go via cache
625 i = remap_instruction_operand_from_cache(which);
626 } else {
627 if (tag_at(which).is_invoke_dynamic()) {
628 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
629 assert(tag_at(pool_index).is_name_and_type(), "");
630 return pool_index;
631 }
632 }
633 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
634 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
635 jint ref_index = *int_at_addr(i);
636 return extract_high_short_from_int(ref_index);
637 }
638
639 constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
640 int pool_index = which;
641 if (!uncached && cache() != NULL) {
642 if (ConstantPool::is_invokedynamic_index(which)) {
643 // Invokedynamic index is index into resolved_references
644 pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
645 } else {
646 // change byte-ordering and go via cache
647 pool_index = remap_instruction_operand_from_cache(which);
648 }
649 }
650 return tag_at(pool_index);
651 }
652
653 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
654 guarantee(!ConstantPool::is_invokedynamic_index(which),
655 "an invokedynamic instruction does not have a klass");
656 int i = which;
657 if (!uncached && cache() != NULL) {
658 // change byte-ordering and go via cache
659 i = remap_instruction_operand_from_cache(which);
660 }
661 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
662 jint ref_index = *int_at_addr(i);
663 return extract_low_short_from_int(ref_index);
664 }
665
666
667
668 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
669 int cpc_index = operand;
670 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
671 assert((int)(u2)cpc_index == cpc_index, "clean u2");
672 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
673 return member_index;
674 }
675
676
677 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
678 if (k->is_instance_klass() || k->is_objArray_klass()) {
679 InstanceKlass* holder = this_cp->pool_holder();
680 Klass* elem = k->is_instance_klass() ? k : ObjArrayKlass::cast(k)->bottom_klass();
681
682 // The element type could be a typeArray - we only need the access check if it is
683 // an reference to another class
684 if (elem->is_instance_klass()) {
685 LinkResolver::check_klass_accessability(holder, elem, CHECK);
686 }
687 }
688 }
689
690
691 int ConstantPool::name_ref_index_at(int which_nt) {
692 jint ref_index = name_and_type_at(which_nt);
693 return extract_low_short_from_int(ref_index);
694 }
695
696
697 int ConstantPool::signature_ref_index_at(int which_nt) {
698 jint ref_index = name_and_type_at(which_nt);
699 return extract_high_short_from_int(ref_index);
700 }
701
702
703 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
704 return klass_at(klass_ref_index_at(which), THREAD);
705 }
706
707 Symbol* ConstantPool::klass_name_at(int which) const {
708 return symbol_at(klass_slot_at(which).name_index());
709 }
710
711 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
712 jint ref_index = klass_ref_index_at(which);
713 return klass_at_noresolve(ref_index);
714 }
715
716 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
717 jint ref_index = uncached_klass_ref_index_at(which);
718 return klass_at_noresolve(ref_index);
719 }
720
721 char* ConstantPool::string_at_noresolve(int which) {
722 return unresolved_string_at(which)->as_C_string();
723 }
724
725 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
726 return FieldType::basic_type(symbol_at(which));
727 }
728
729
730 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
731 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
732 if (this_cp->tag_at(index).is_string()) {
733 this_cp->string_at(index, CHECK);
734 }
735 }
736 }
737
738 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
739 // Dig out the detailed message to reuse if possible
740 Symbol* message = java_lang_Throwable::detail_message(pending_exception);
741 if (message != NULL) {
742 return message;
743 }
744
745 // Return specific message for the tag
746 switch (tag.value()) {
747 case JVM_CONSTANT_UnresolvedClass:
748 // return the class name in the error message
749 message = this_cp->klass_name_at(which);
750 break;
751 case JVM_CONSTANT_MethodHandle:
752 // return the method handle name in the error message
753 message = this_cp->method_handle_name_ref_at(which);
754 break;
755 case JVM_CONSTANT_MethodType:
756 // return the method type signature in the error message
757 message = this_cp->method_type_signature_at(which);
758 break;
759 default:
760 ShouldNotReachHere();
761 }
762
763 return message;
764 }
765
766 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
767 Symbol* message = NULL;
768 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
769 assert(error != NULL && message != NULL, "checking");
770 CLEAR_PENDING_EXCEPTION;
771 ResourceMark rm;
772 THROW_MSG(error, message->as_C_string());
773 }
774
775 // If resolution for Class, MethodHandle or MethodType fails, save the exception
776 // in the resolution error table, so that the same exception is thrown again.
777 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
778 constantTag tag, TRAPS) {
779 Symbol* error = PENDING_EXCEPTION->klass()->name();
780
781 int error_tag = tag.error_value();
782
783 if (!PENDING_EXCEPTION->
784 is_a(SystemDictionary::LinkageError_klass())) {
785 // Just throw the exception and don't prevent these classes from
786 // being loaded due to virtual machine errors like StackOverflow
787 // and OutOfMemoryError, etc, or if the thread was hit by stop()
788 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
789 } else if (this_cp->tag_at(which).value() != error_tag) {
790 Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
791 SystemDictionary::add_resolution_error(this_cp, which, error, message);
792 // CAS in the tag. If a thread beat us to registering this error that's fine.
793 // If another thread resolved the reference, this is a race condition. This
794 // thread may have had a security manager or something temporary.
795 // This doesn't deterministically get an error. So why do we save this?
796 // We save this because jvmti can add classes to the bootclass path after
797 // this error, so it needs to get the same error if the error is first.
798 jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
799 (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
800 if (old_tag != error_tag && old_tag != tag.value()) {
801 // MethodHandles and MethodType doesn't change to resolved version.
802 assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
803 // Forget the exception and use the resolved class.
804 CLEAR_PENDING_EXCEPTION;
805 }
806 } else {
807 // some other thread put this in error state
808 throw_resolution_error(this_cp, which, CHECK);
809 }
810 }
811
812 // Called to resolve constants in the constant pool and return an oop.
813 // Some constant pool entries cache their resolved oop. This is also
814 // called to create oops from constants to use in arguments for invokedynamic
815 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS) {
816 oop result_oop = NULL;
817 Handle throw_exception;
818
819 if (cache_index == _possible_index_sentinel) {
820 // It is possible that this constant is one which is cached in the objects.
821 // We'll do a linear search. This should be OK because this usage is rare.
822 assert(index > 0, "valid index");
823 cache_index = this_cp->cp_to_object_index(index);
824 }
825 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
826 assert(index == _no_index_sentinel || index >= 0, "");
827
828 if (cache_index >= 0) {
829 result_oop = this_cp->resolved_references()->obj_at(cache_index);
830 if (result_oop != NULL) {
831 return result_oop;
832 // That was easy...
833 }
834 index = this_cp->object_to_cp_index(cache_index);
835 }
836
837 jvalue prim_value; // temp used only in a few cases below
838
839 constantTag tag = this_cp->tag_at(index);
840
841 switch (tag.value()) {
842
843 case JVM_CONSTANT_UnresolvedClass:
844 case JVM_CONSTANT_UnresolvedClassInError:
845 case JVM_CONSTANT_Class:
846 {
847 assert(cache_index == _no_index_sentinel, "should not have been set");
848 Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
849 // ldc wants the java mirror.
850 result_oop = resolved->java_mirror();
851 break;
852 }
853
854 case JVM_CONSTANT_String:
855 assert(cache_index != _no_index_sentinel, "should have been set");
856 if (this_cp->is_pseudo_string_at(index)) {
857 result_oop = this_cp->pseudo_string_at(index, cache_index);
858 break;
859 }
860 result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
861 break;
862
863 case JVM_CONSTANT_MethodHandleInError:
864 case JVM_CONSTANT_MethodTypeInError:
865 {
866 throw_resolution_error(this_cp, index, CHECK_NULL);
867 break;
868 }
869
870 case JVM_CONSTANT_MethodHandle:
871 {
872 int ref_kind = this_cp->method_handle_ref_kind_at(index);
873 int callee_index = this_cp->method_handle_klass_index_at(index);
874 Symbol* name = this_cp->method_handle_name_ref_at(index);
875 Symbol* signature = this_cp->method_handle_signature_ref_at(index);
876 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(index));
877 { ResourceMark rm(THREAD);
878 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
879 ref_kind, index, this_cp->method_handle_index_at(index),
880 callee_index, name->as_C_string(), signature->as_C_string());
881 }
882
883 Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
884
885 // Check constant pool method consistency
886 if ((callee->is_interface() && m_tag.is_method()) ||
887 ((!callee->is_interface() && m_tag.is_interface_method()))) {
888 ResourceMark rm(THREAD);
889 char buf[400];
890 jio_snprintf(buf, sizeof(buf),
891 "Inconsistent constant pool data in classfile for class %s. "
892 "Method %s%s at index %d is %s and should be %s",
893 callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
894 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
895 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
896 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
897 }
898
899 Klass* klass = this_cp->pool_holder();
900 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
901 callee, name, signature,
902 THREAD);
903 result_oop = value();
904 if (HAS_PENDING_EXCEPTION) {
905 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
906 }
907 break;
908 }
909
910 case JVM_CONSTANT_MethodType:
911 {
912 Symbol* signature = this_cp->method_type_signature_at(index);
913 { ResourceMark rm(THREAD);
914 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
915 index, this_cp->method_type_index_at(index),
916 signature->as_C_string());
917 }
918 Klass* klass = this_cp->pool_holder();
919 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
920 result_oop = value();
921 if (HAS_PENDING_EXCEPTION) {
922 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
923 }
924 break;
925 }
926
927 case JVM_CONSTANT_Integer:
928 assert(cache_index == _no_index_sentinel, "should not have been set");
929 prim_value.i = this_cp->int_at(index);
930 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
931 break;
932
933 case JVM_CONSTANT_Float:
934 assert(cache_index == _no_index_sentinel, "should not have been set");
935 prim_value.f = this_cp->float_at(index);
936 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
937 break;
938
939 case JVM_CONSTANT_Long:
940 assert(cache_index == _no_index_sentinel, "should not have been set");
941 prim_value.j = this_cp->long_at(index);
942 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
943 break;
944
945 case JVM_CONSTANT_Double:
946 assert(cache_index == _no_index_sentinel, "should not have been set");
947 prim_value.d = this_cp->double_at(index);
948 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
949 break;
950
951 default:
952 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
953 this_cp(), index, cache_index, tag.value()));
954 assert(false, "unexpected constant tag");
955 break;
956 }
957
958 if (cache_index >= 0) {
959 // Benign race condition: resolved_references may already be filled in.
960 // The important thing here is that all threads pick up the same result.
961 // It doesn't matter which racing thread wins, as long as only one
962 // result is used by all threads, and all future queries.
963 oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
964 if (old_result == NULL) {
965 return result_oop; // was installed
966 } else {
967 // Return the winning thread's result. This can be different than
968 // the result here for MethodHandles.
969 return old_result;
970 }
971 } else {
972 return result_oop;
973 }
974 }
975
976 oop ConstantPool::uncached_string_at(int which, TRAPS) {
977 Symbol* sym = unresolved_string_at(which);
978 oop str = StringTable::intern(sym, CHECK_(NULL));
979 assert(java_lang_String::is_instance(str), "must be string");
980 return str;
981 }
982
983
984 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
985 assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
986
987 Handle bsm;
988 int argc;
989 {
990 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
991 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
992 // It is accompanied by the optional arguments.
993 int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
994 oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
995 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
996 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
997 }
998
999 // Extract the optional static arguments.
1000 argc = this_cp->invoke_dynamic_argument_count_at(index);
1001 if (argc == 0) return bsm_oop;
1002
1003 bsm = Handle(THREAD, bsm_oop);
1004 }
1005
1006 objArrayHandle info;
1007 {
1008 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
1009 info = objArrayHandle(THREAD, info_oop);
1010 }
1011
1012 info->obj_at_put(0, bsm());
1013 for (int i = 0; i < argc; i++) {
1014 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1015 oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
1016 info->obj_at_put(1+i, arg_oop);
1017 }
1018
1019 return info();
1020 }
1021
1022 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
1023 // If the string has already been interned, this entry will be non-null
1024 oop str = this_cp->resolved_references()->obj_at(obj_index);
1025 if (str != NULL) return str;
1026 Symbol* sym = this_cp->unresolved_string_at(which);
1027 str = StringTable::intern(sym, CHECK_(NULL));
1028 this_cp->string_at_put(which, obj_index, str);
1029 assert(java_lang_String::is_instance(str), "must be string");
1030 return str;
1031 }
1032
1033
1034 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
1035 // Names are interned, so we can compare Symbol*s directly
1036 Symbol* cp_name = klass_name_at(which);
1037 return (cp_name == k->name());
1038 }
1039
1040
1041 // Iterate over symbols and decrement ones which are Symbol*s
1042 // This is done during GC.
1043 // Only decrement the UTF8 symbols. Strings point to
1044 // these symbols but didn't increment the reference count.
1045 void ConstantPool::unreference_symbols() {
1046 for (int index = 1; index < length(); index++) { // Index 0 is unused
1047 constantTag tag = tag_at(index);
1048 if (tag.is_symbol()) {
1049 symbol_at(index)->decrement_refcount();
1050 }
1051 }
1052 }
1053
1054
1055 // Compare this constant pool's entry at index1 to the constant pool
1056 // cp2's entry at index2.
1057 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1058 int index2, TRAPS) {
1059
1060 // The error tags are equivalent to non-error tags when comparing
1061 jbyte t1 = tag_at(index1).non_error_value();
1062 jbyte t2 = cp2->tag_at(index2).non_error_value();
1063
1064 if (t1 != t2) {
1065 // Not the same entry type so there is nothing else to check. Note
1066 // that this style of checking will consider resolved/unresolved
1067 // class pairs as different.
1068 // From the ConstantPool* API point of view, this is correct
1069 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1070 // plays out in the context of ConstantPool* merging.
1071 return false;
1072 }
1073
1074 switch (t1) {
1075 case JVM_CONSTANT_Class:
1076 {
1077 Klass* k1 = klass_at(index1, CHECK_false);
1078 Klass* k2 = cp2->klass_at(index2, CHECK_false);
1079 if (k1 == k2) {
1080 return true;
1081 }
1082 } break;
1083
1084 case JVM_CONSTANT_ClassIndex:
1085 {
1086 int recur1 = klass_index_at(index1);
1087 int recur2 = cp2->klass_index_at(index2);
1088 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1089 if (match) {
1090 return true;
1091 }
1092 } break;
1093
1094 case JVM_CONSTANT_Double:
1095 {
1096 jdouble d1 = double_at(index1);
1097 jdouble d2 = cp2->double_at(index2);
1098 if (d1 == d2) {
1099 return true;
1100 }
1101 } break;
1102
1103 case JVM_CONSTANT_Fieldref:
1104 case JVM_CONSTANT_InterfaceMethodref:
1105 case JVM_CONSTANT_Methodref:
1106 {
1107 int recur1 = uncached_klass_ref_index_at(index1);
1108 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1109 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1110 if (match) {
1111 recur1 = uncached_name_and_type_ref_index_at(index1);
1112 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1113 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1114 if (match) {
1115 return true;
1116 }
1117 }
1118 } break;
1119
1120 case JVM_CONSTANT_Float:
1121 {
1122 jfloat f1 = float_at(index1);
1123 jfloat f2 = cp2->float_at(index2);
1124 if (f1 == f2) {
1125 return true;
1126 }
1127 } break;
1128
1129 case JVM_CONSTANT_Integer:
1130 {
1131 jint i1 = int_at(index1);
1132 jint i2 = cp2->int_at(index2);
1133 if (i1 == i2) {
1134 return true;
1135 }
1136 } break;
1137
1138 case JVM_CONSTANT_Long:
1139 {
1140 jlong l1 = long_at(index1);
1141 jlong l2 = cp2->long_at(index2);
1142 if (l1 == l2) {
1143 return true;
1144 }
1145 } break;
1146
1147 case JVM_CONSTANT_NameAndType:
1148 {
1149 int recur1 = name_ref_index_at(index1);
1150 int recur2 = cp2->name_ref_index_at(index2);
1151 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1152 if (match) {
1153 recur1 = signature_ref_index_at(index1);
1154 recur2 = cp2->signature_ref_index_at(index2);
1155 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1156 if (match) {
1157 return true;
1158 }
1159 }
1160 } break;
1161
1162 case JVM_CONSTANT_StringIndex:
1163 {
1164 int recur1 = string_index_at(index1);
1165 int recur2 = cp2->string_index_at(index2);
1166 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1167 if (match) {
1168 return true;
1169 }
1170 } break;
1171
1172 case JVM_CONSTANT_UnresolvedClass:
1173 {
1174 Symbol* k1 = klass_name_at(index1);
1175 Symbol* k2 = cp2->klass_name_at(index2);
1176 if (k1 == k2) {
1177 return true;
1178 }
1179 } break;
1180
1181 case JVM_CONSTANT_MethodType:
1182 {
1183 int k1 = method_type_index_at(index1);
1184 int k2 = cp2->method_type_index_at(index2);
1185 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1186 if (match) {
1187 return true;
1188 }
1189 } break;
1190
1191 case JVM_CONSTANT_MethodHandle:
1192 {
1193 int k1 = method_handle_ref_kind_at(index1);
1194 int k2 = cp2->method_handle_ref_kind_at(index2);
1195 if (k1 == k2) {
1196 int i1 = method_handle_index_at(index1);
1197 int i2 = cp2->method_handle_index_at(index2);
1198 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1199 if (match) {
1200 return true;
1201 }
1202 }
1203 } break;
1204
1205 case JVM_CONSTANT_InvokeDynamic:
1206 {
1207 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1208 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1209 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1210 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1211 // separate statements and variables because CHECK_false is used
1212 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1213 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1214 return (match_entry && match_operand);
1215 } break;
1216
1217 case JVM_CONSTANT_String:
1218 {
1219 Symbol* s1 = unresolved_string_at(index1);
1220 Symbol* s2 = cp2->unresolved_string_at(index2);
1221 if (s1 == s2) {
1222 return true;
1223 }
1224 } break;
1225
1226 case JVM_CONSTANT_Utf8:
1227 {
1228 Symbol* s1 = symbol_at(index1);
1229 Symbol* s2 = cp2->symbol_at(index2);
1230 if (s1 == s2) {
1231 return true;
1232 }
1233 } break;
1234
1235 // Invalid is used as the tag for the second constant pool entry
1236 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1237 // not be seen by itself.
1238 case JVM_CONSTANT_Invalid: // fall through
1239
1240 default:
1241 ShouldNotReachHere();
1242 break;
1243 }
1244
1245 return false;
1246 } // end compare_entry_to()
1247
1248
1249 // Resize the operands array with delta_len and delta_size.
1250 // Used in RedefineClasses for CP merge.
1251 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1252 int old_len = operand_array_length(operands());
1253 int new_len = old_len + delta_len;
1254 int min_len = (delta_len > 0) ? old_len : new_len;
1255
1256 int old_size = operands()->length();
1257 int new_size = old_size + delta_size;
1258 int min_size = (delta_size > 0) ? old_size : new_size;
1259
1260 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1261 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1262
1263 // Set index in the resized array for existing elements only
1264 for (int idx = 0; idx < min_len; idx++) {
1265 int offset = operand_offset_at(idx); // offset in original array
1266 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1267 }
1268 // Copy the bootstrap specifiers only
1269 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1270 new_ops->adr_at(2*new_len),
1271 (min_size - 2*min_len) * sizeof(u2));
1272 // Explicitly deallocate old operands array.
1273 // Note, it is not needed for 7u backport.
1274 if ( operands() != NULL) { // the safety check
1275 MetadataFactory::free_array<u2>(loader_data, operands());
1276 }
1277 set_operands(new_ops);
1278 } // end resize_operands()
1279
1280
1281 // Extend the operands array with the length and size of the ext_cp operands.
1282 // Used in RedefineClasses for CP merge.
1283 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1284 int delta_len = operand_array_length(ext_cp->operands());
1285 if (delta_len == 0) {
1286 return; // nothing to do
1287 }
1288 int delta_size = ext_cp->operands()->length();
1289
1290 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1291
1292 if (operand_array_length(operands()) == 0) {
1293 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1294 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1295 // The first element index defines the offset of second part
1296 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1297 set_operands(new_ops);
1298 } else {
1299 resize_operands(delta_len, delta_size, CHECK);
1300 }
1301
1302 } // end extend_operands()
1303
1304
1305 // Shrink the operands array to a smaller array with new_len length.
1306 // Used in RedefineClasses for CP merge.
1307 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1308 int old_len = operand_array_length(operands());
1309 if (new_len == old_len) {
1310 return; // nothing to do
1311 }
1312 assert(new_len < old_len, "shrunken operands array must be smaller");
1313
1314 int free_base = operand_next_offset_at(new_len - 1);
1315 int delta_len = new_len - old_len;
1316 int delta_size = 2*delta_len + free_base - operands()->length();
1317
1318 resize_operands(delta_len, delta_size, CHECK);
1319
1320 } // end shrink_operands()
1321
1322
1323 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1324 const constantPoolHandle& to_cp,
1325 TRAPS) {
1326
1327 int from_oplen = operand_array_length(from_cp->operands());
1328 int old_oplen = operand_array_length(to_cp->operands());
1329 if (from_oplen != 0) {
1330 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1331 // append my operands to the target's operands array
1332 if (old_oplen == 0) {
1333 // Can't just reuse from_cp's operand list because of deallocation issues
1334 int len = from_cp->operands()->length();
1335 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1336 Copy::conjoint_memory_atomic(
1337 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1338 to_cp->set_operands(new_ops);
1339 } else {
1340 int old_len = to_cp->operands()->length();
1341 int from_len = from_cp->operands()->length();
1342 int old_off = old_oplen * sizeof(u2);
1343 int from_off = from_oplen * sizeof(u2);
1344 // Use the metaspace for the destination constant pool
1345 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1346 int fillp = 0, len = 0;
1347 // first part of dest
1348 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1349 new_operands->adr_at(fillp),
1350 (len = old_off) * sizeof(u2));
1351 fillp += len;
1352 // first part of src
1353 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1354 new_operands->adr_at(fillp),
1355 (len = from_off) * sizeof(u2));
1356 fillp += len;
1357 // second part of dest
1358 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1359 new_operands->adr_at(fillp),
1360 (len = old_len - old_off) * sizeof(u2));
1361 fillp += len;
1362 // second part of src
1363 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1364 new_operands->adr_at(fillp),
1365 (len = from_len - from_off) * sizeof(u2));
1366 fillp += len;
1367 assert(fillp == new_operands->length(), "");
1368
1369 // Adjust indexes in the first part of the copied operands array.
1370 for (int j = 0; j < from_oplen; j++) {
1371 int offset = operand_offset_at(new_operands, old_oplen + j);
1372 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1373 offset += old_len; // every new tuple is preceded by old_len extra u2's
1374 operand_offset_at_put(new_operands, old_oplen + j, offset);
1375 }
1376
1377 // replace target operands array with combined array
1378 to_cp->set_operands(new_operands);
1379 }
1380 }
1381 } // end copy_operands()
1382
1383
1384 // Copy this constant pool's entries at start_i to end_i (inclusive)
1385 // to the constant pool to_cp's entries starting at to_i. A total of
1386 // (end_i - start_i) + 1 entries are copied.
1387 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1388 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1389
1390
1391 int dest_i = to_i; // leave original alone for debug purposes
1392
1393 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1394 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1395
1396 switch (from_cp->tag_at(src_i).value()) {
1397 case JVM_CONSTANT_Double:
1398 case JVM_CONSTANT_Long:
1399 // double and long take two constant pool entries
1400 src_i += 2;
1401 dest_i += 2;
1402 break;
1403
1404 default:
1405 // all others take one constant pool entry
1406 src_i++;
1407 dest_i++;
1408 break;
1409 }
1410 }
1411 copy_operands(from_cp, to_cp, CHECK);
1412
1413 } // end copy_cp_to_impl()
1414
1415
1416 // Copy this constant pool's entry at from_i to the constant pool
1417 // to_cp's entry at to_i.
1418 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1419 const constantPoolHandle& to_cp, int to_i,
1420 TRAPS) {
1421
1422 int tag = from_cp->tag_at(from_i).value();
1423 switch (tag) {
1424 case JVM_CONSTANT_ClassIndex:
1425 {
1426 jint ki = from_cp->klass_index_at(from_i);
1427 to_cp->klass_index_at_put(to_i, ki);
1428 } break;
1429
1430 case JVM_CONSTANT_Double:
1431 {
1432 jdouble d = from_cp->double_at(from_i);
1433 to_cp->double_at_put(to_i, d);
1434 // double takes two constant pool entries so init second entry's tag
1435 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1436 } break;
1437
1438 case JVM_CONSTANT_Fieldref:
1439 {
1440 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1441 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1442 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1443 } break;
1444
1445 case JVM_CONSTANT_Float:
1446 {
1447 jfloat f = from_cp->float_at(from_i);
1448 to_cp->float_at_put(to_i, f);
1449 } break;
1450
1451 case JVM_CONSTANT_Integer:
1452 {
1453 jint i = from_cp->int_at(from_i);
1454 to_cp->int_at_put(to_i, i);
1455 } break;
1456
1457 case JVM_CONSTANT_InterfaceMethodref:
1458 {
1459 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1460 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1461 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1462 } break;
1463
1464 case JVM_CONSTANT_Long:
1465 {
1466 jlong l = from_cp->long_at(from_i);
1467 to_cp->long_at_put(to_i, l);
1468 // long takes two constant pool entries so init second entry's tag
1469 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1470 } break;
1471
1472 case JVM_CONSTANT_Methodref:
1473 {
1474 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1475 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1476 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1477 } break;
1478
1479 case JVM_CONSTANT_NameAndType:
1480 {
1481 int name_ref_index = from_cp->name_ref_index_at(from_i);
1482 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1483 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1484 } break;
1485
1486 case JVM_CONSTANT_StringIndex:
1487 {
1488 jint si = from_cp->string_index_at(from_i);
1489 to_cp->string_index_at_put(to_i, si);
1490 } break;
1491
1492 case JVM_CONSTANT_Class:
1493 case JVM_CONSTANT_UnresolvedClass:
1494 case JVM_CONSTANT_UnresolvedClassInError:
1495 {
1496 // Revert to JVM_CONSTANT_ClassIndex
1497 int name_index = from_cp->klass_slot_at(from_i).name_index();
1498 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1499 to_cp->klass_index_at_put(to_i, name_index);
1500 } break;
1501
1502 case JVM_CONSTANT_String:
1503 {
1504 Symbol* s = from_cp->unresolved_string_at(from_i);
1505 to_cp->unresolved_string_at_put(to_i, s);
1506 } break;
1507
1508 case JVM_CONSTANT_Utf8:
1509 {
1510 Symbol* s = from_cp->symbol_at(from_i);
1511 // Need to increase refcount, the old one will be thrown away and deferenced
1512 s->increment_refcount();
1513 to_cp->symbol_at_put(to_i, s);
1514 } break;
1515
1516 case JVM_CONSTANT_MethodType:
1517 case JVM_CONSTANT_MethodTypeInError:
1518 {
1519 jint k = from_cp->method_type_index_at(from_i);
1520 to_cp->method_type_index_at_put(to_i, k);
1521 } break;
1522
1523 case JVM_CONSTANT_MethodHandle:
1524 case JVM_CONSTANT_MethodHandleInError:
1525 {
1526 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1527 int k2 = from_cp->method_handle_index_at(from_i);
1528 to_cp->method_handle_index_at_put(to_i, k1, k2);
1529 } break;
1530
1531 case JVM_CONSTANT_InvokeDynamic:
1532 {
1533 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1534 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1535 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1536 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1537 } break;
1538
1539 // Invalid is used as the tag for the second constant pool entry
1540 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1541 // not be seen by itself.
1542 case JVM_CONSTANT_Invalid: // fall through
1543
1544 default:
1545 {
1546 ShouldNotReachHere();
1547 } break;
1548 }
1549 } // end copy_entry_to()
1550
1551 // Search constant pool search_cp for an entry that matches this
1552 // constant pool's entry at pattern_i. Returns the index of a
1553 // matching entry or zero (0) if there is no matching entry.
1554 int ConstantPool::find_matching_entry(int pattern_i,
1555 const constantPoolHandle& search_cp, TRAPS) {
1556
1557 // index zero (0) is not used
1558 for (int i = 1; i < search_cp->length(); i++) {
1559 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1560 if (found) {
1561 return i;
1562 }
1563 }
1564
1565 return 0; // entry not found; return unused index zero (0)
1566 } // end find_matching_entry()
1567
1568
1569 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1570 // cp2's bootstrap specifier at idx2.
1571 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1572 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1573 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1574 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1575
1576 if (!match) {
1577 return false;
1578 }
1579 int argc = operand_argument_count_at(idx1);
1580 if (argc == cp2->operand_argument_count_at(idx2)) {
1581 for (int j = 0; j < argc; j++) {
1582 k1 = operand_argument_index_at(idx1, j);
1583 k2 = cp2->operand_argument_index_at(idx2, j);
1584 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1585 if (!match) {
1586 return false;
1587 }
1588 }
1589 return true; // got through loop; all elements equal
1590 }
1591 return false;
1592 } // end compare_operand_to()
1593
1594 // Search constant pool search_cp for a bootstrap specifier that matches
1595 // this constant pool's bootstrap specifier at pattern_i index.
1596 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1597 int ConstantPool::find_matching_operand(int pattern_i,
1598 const constantPoolHandle& search_cp, int search_len, TRAPS) {
1599 for (int i = 0; i < search_len; i++) {
1600 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1601 if (found) {
1602 return i;
1603 }
1604 }
1605 return -1; // bootstrap specifier not found; return unused index (-1)
1606 } // end find_matching_operand()
1607
1608
1609 #ifndef PRODUCT
1610
1611 const char* ConstantPool::printable_name_at(int which) {
1612
1613 constantTag tag = tag_at(which);
1614
1615 if (tag.is_string()) {
1616 return string_at_noresolve(which);
1617 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1618 return klass_name_at(which)->as_C_string();
1619 } else if (tag.is_symbol()) {
1620 return symbol_at(which)->as_C_string();
1621 }
1622 return "";
1623 }
1624
1625 #endif // PRODUCT
1626
1627
1628 // JVMTI GetConstantPool support
1629
1630 // For debugging of constant pool
1631 const bool debug_cpool = false;
1632
1633 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1634
1635 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1636 const char* WARN_MSG = "Must not be such entry!";
1637 jint size = 0;
1638 u2 idx1, idx2;
1639
1640 for (jint idx = 1; idx < cnt; idx++) {
1641 jint ent_size = 0;
1642 u1 tag = *bytes++;
1643 size++; // count tag
1644
1645 printf("const #%03d, tag: %02d ", idx, tag);
1646 switch(tag) {
1647 case JVM_CONSTANT_Invalid: {
1648 printf("Invalid");
1649 break;
1650 }
1651 case JVM_CONSTANT_Unicode: {
1652 printf("Unicode %s", WARN_MSG);
1653 break;
1654 }
1655 case JVM_CONSTANT_Utf8: {
1656 u2 len = Bytes::get_Java_u2(bytes);
1657 char str[128];
1658 if (len > 127) {
1659 len = 127;
1660 }
1661 strncpy(str, (char *) (bytes+2), len);
1662 str[len] = '\0';
1663 printf("Utf8 \"%s\"", str);
1664 ent_size = 2 + len;
1665 break;
1666 }
1667 case JVM_CONSTANT_Integer: {
1668 u4 val = Bytes::get_Java_u4(bytes);
1669 printf("int %d", *(int *) &val);
1670 ent_size = 4;
1671 break;
1672 }
1673 case JVM_CONSTANT_Float: {
1674 u4 val = Bytes::get_Java_u4(bytes);
1675 printf("float %5.3ff", *(float *) &val);
1676 ent_size = 4;
1677 break;
1678 }
1679 case JVM_CONSTANT_Long: {
1680 u8 val = Bytes::get_Java_u8(bytes);
1681 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1682 ent_size = 8;
1683 idx++; // Long takes two cpool slots
1684 break;
1685 }
1686 case JVM_CONSTANT_Double: {
1687 u8 val = Bytes::get_Java_u8(bytes);
1688 printf("double %5.3fd", *(jdouble *)&val);
1689 ent_size = 8;
1690 idx++; // Double takes two cpool slots
1691 break;
1692 }
1693 case JVM_CONSTANT_Class: {
1694 idx1 = Bytes::get_Java_u2(bytes);
1695 printf("class #%03d", idx1);
1696 ent_size = 2;
1697 break;
1698 }
1699 case JVM_CONSTANT_String: {
1700 idx1 = Bytes::get_Java_u2(bytes);
1701 printf("String #%03d", idx1);
1702 ent_size = 2;
1703 break;
1704 }
1705 case JVM_CONSTANT_Fieldref: {
1706 idx1 = Bytes::get_Java_u2(bytes);
1707 idx2 = Bytes::get_Java_u2(bytes+2);
1708 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1709 ent_size = 4;
1710 break;
1711 }
1712 case JVM_CONSTANT_Methodref: {
1713 idx1 = Bytes::get_Java_u2(bytes);
1714 idx2 = Bytes::get_Java_u2(bytes+2);
1715 printf("Method #%03d, #%03d", idx1, idx2);
1716 ent_size = 4;
1717 break;
1718 }
1719 case JVM_CONSTANT_InterfaceMethodref: {
1720 idx1 = Bytes::get_Java_u2(bytes);
1721 idx2 = Bytes::get_Java_u2(bytes+2);
1722 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1723 ent_size = 4;
1724 break;
1725 }
1726 case JVM_CONSTANT_NameAndType: {
1727 idx1 = Bytes::get_Java_u2(bytes);
1728 idx2 = Bytes::get_Java_u2(bytes+2);
1729 printf("NameAndType #%03d, #%03d", idx1, idx2);
1730 ent_size = 4;
1731 break;
1732 }
1733 case JVM_CONSTANT_ClassIndex: {
1734 printf("ClassIndex %s", WARN_MSG);
1735 break;
1736 }
1737 case JVM_CONSTANT_UnresolvedClass: {
1738 printf("UnresolvedClass: %s", WARN_MSG);
1739 break;
1740 }
1741 case JVM_CONSTANT_UnresolvedClassInError: {
1742 printf("UnresolvedClassInErr: %s", WARN_MSG);
1743 break;
1744 }
1745 case JVM_CONSTANT_StringIndex: {
1746 printf("StringIndex: %s", WARN_MSG);
1747 break;
1748 }
1749 }
1750 printf(";\n");
1751 bytes += ent_size;
1752 size += ent_size;
1753 }
1754 printf("Cpool size: %d\n", size);
1755 fflush(0);
1756 return;
1757 } /* end print_cpool_bytes */
1758
1759
1760 // Returns size of constant pool entry.
1761 jint ConstantPool::cpool_entry_size(jint idx) {
1762 switch(tag_at(idx).value()) {
1763 case JVM_CONSTANT_Invalid:
1764 case JVM_CONSTANT_Unicode:
1765 return 1;
1766
1767 case JVM_CONSTANT_Utf8:
1768 return 3 + symbol_at(idx)->utf8_length();
1769
1770 case JVM_CONSTANT_Class:
1771 case JVM_CONSTANT_String:
1772 case JVM_CONSTANT_ClassIndex:
1773 case JVM_CONSTANT_UnresolvedClass:
1774 case JVM_CONSTANT_UnresolvedClassInError:
1775 case JVM_CONSTANT_StringIndex:
1776 case JVM_CONSTANT_MethodType:
1777 case JVM_CONSTANT_MethodTypeInError:
1778 return 3;
1779
1780 case JVM_CONSTANT_MethodHandle:
1781 case JVM_CONSTANT_MethodHandleInError:
1782 return 4; //tag, ref_kind, ref_index
1783
1784 case JVM_CONSTANT_Integer:
1785 case JVM_CONSTANT_Float:
1786 case JVM_CONSTANT_Fieldref:
1787 case JVM_CONSTANT_Methodref:
1788 case JVM_CONSTANT_InterfaceMethodref:
1789 case JVM_CONSTANT_NameAndType:
1790 return 5;
1791
1792 case JVM_CONSTANT_InvokeDynamic:
1793 // u1 tag, u2 bsm, u2 nt
1794 return 5;
1795
1796 case JVM_CONSTANT_Long:
1797 case JVM_CONSTANT_Double:
1798 return 9;
1799 }
1800 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1801 return 1;
1802 } /* end cpool_entry_size */
1803
1804
1805 // SymbolHashMap is used to find a constant pool index from a string.
1806 // This function fills in SymbolHashMaps, one for utf8s and one for
1807 // class names, returns size of the cpool raw bytes.
1808 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1809 SymbolHashMap *classmap) {
1810 jint size = 0;
1811
1812 for (u2 idx = 1; idx < length(); idx++) {
1813 u2 tag = tag_at(idx).value();
1814 size += cpool_entry_size(idx);
1815
1816 switch(tag) {
1817 case JVM_CONSTANT_Utf8: {
1818 Symbol* sym = symbol_at(idx);
1819 symmap->add_entry(sym, idx);
1820 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1821 break;
1822 }
1823 case JVM_CONSTANT_Class:
1824 case JVM_CONSTANT_UnresolvedClass:
1825 case JVM_CONSTANT_UnresolvedClassInError: {
1826 Symbol* sym = klass_name_at(idx);
1827 classmap->add_entry(sym, idx);
1828 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1829 break;
1830 }
1831 case JVM_CONSTANT_Long:
1832 case JVM_CONSTANT_Double: {
1833 idx++; // Both Long and Double take two cpool slots
1834 break;
1835 }
1836 }
1837 }
1838 return size;
1839 } /* end hash_utf8_entries_to */
1840
1841
1842 // Copy cpool bytes.
1843 // Returns:
1844 // 0, in case of OutOfMemoryError
1845 // -1, in case of internal error
1846 // > 0, count of the raw cpool bytes that have been copied
1847 int ConstantPool::copy_cpool_bytes(int cpool_size,
1848 SymbolHashMap* tbl,
1849 unsigned char *bytes) {
1850 u2 idx1, idx2;
1851 jint size = 0;
1852 jint cnt = length();
1853 unsigned char *start_bytes = bytes;
1854
1855 for (jint idx = 1; idx < cnt; idx++) {
1856 u1 tag = tag_at(idx).value();
1857 jint ent_size = cpool_entry_size(idx);
1858
1859 assert(size + ent_size <= cpool_size, "Size mismatch");
1860
1861 *bytes = tag;
1862 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
1863 switch(tag) {
1864 case JVM_CONSTANT_Invalid: {
1865 DBG(printf("JVM_CONSTANT_Invalid"));
1866 break;
1867 }
1868 case JVM_CONSTANT_Unicode: {
1869 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1870 DBG(printf("JVM_CONSTANT_Unicode"));
1871 break;
1872 }
1873 case JVM_CONSTANT_Utf8: {
1874 Symbol* sym = symbol_at(idx);
1875 char* str = sym->as_utf8();
1876 // Warning! It's crashing on x86 with len = sym->utf8_length()
1877 int len = (int) strlen(str);
1878 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1879 for (int i = 0; i < len; i++) {
1880 bytes[3+i] = (u1) str[i];
1881 }
1882 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1883 break;
1884 }
1885 case JVM_CONSTANT_Integer: {
1886 jint val = int_at(idx);
1887 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1888 break;
1889 }
1890 case JVM_CONSTANT_Float: {
1891 jfloat val = float_at(idx);
1892 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1893 break;
1894 }
1895 case JVM_CONSTANT_Long: {
1896 jlong val = long_at(idx);
1897 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1898 idx++; // Long takes two cpool slots
1899 break;
1900 }
1901 case JVM_CONSTANT_Double: {
1902 jdouble val = double_at(idx);
1903 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1904 idx++; // Double takes two cpool slots
1905 break;
1906 }
1907 case JVM_CONSTANT_Class:
1908 case JVM_CONSTANT_UnresolvedClass:
1909 case JVM_CONSTANT_UnresolvedClassInError: {
1910 *bytes = JVM_CONSTANT_Class;
1911 Symbol* sym = klass_name_at(idx);
1912 idx1 = tbl->symbol_to_value(sym);
1913 assert(idx1 != 0, "Have not found a hashtable entry");
1914 Bytes::put_Java_u2((address) (bytes+1), idx1);
1915 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1916 break;
1917 }
1918 case JVM_CONSTANT_String: {
1919 *bytes = JVM_CONSTANT_String;
1920 Symbol* sym = unresolved_string_at(idx);
1921 idx1 = tbl->symbol_to_value(sym);
1922 assert(idx1 != 0, "Have not found a hashtable entry");
1923 Bytes::put_Java_u2((address) (bytes+1), idx1);
1924 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1925 break;
1926 }
1927 case JVM_CONSTANT_Fieldref:
1928 case JVM_CONSTANT_Methodref:
1929 case JVM_CONSTANT_InterfaceMethodref: {
1930 idx1 = uncached_klass_ref_index_at(idx);
1931 idx2 = uncached_name_and_type_ref_index_at(idx);
1932 Bytes::put_Java_u2((address) (bytes+1), idx1);
1933 Bytes::put_Java_u2((address) (bytes+3), idx2);
1934 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1935 break;
1936 }
1937 case JVM_CONSTANT_NameAndType: {
1938 idx1 = name_ref_index_at(idx);
1939 idx2 = signature_ref_index_at(idx);
1940 Bytes::put_Java_u2((address) (bytes+1), idx1);
1941 Bytes::put_Java_u2((address) (bytes+3), idx2);
1942 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1943 break;
1944 }
1945 case JVM_CONSTANT_ClassIndex: {
1946 *bytes = JVM_CONSTANT_Class;
1947 idx1 = klass_index_at(idx);
1948 Bytes::put_Java_u2((address) (bytes+1), idx1);
1949 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1950 break;
1951 }
1952 case JVM_CONSTANT_StringIndex: {
1953 *bytes = JVM_CONSTANT_String;
1954 idx1 = string_index_at(idx);
1955 Bytes::put_Java_u2((address) (bytes+1), idx1);
1956 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1957 break;
1958 }
1959 case JVM_CONSTANT_MethodHandle:
1960 case JVM_CONSTANT_MethodHandleInError: {
1961 *bytes = JVM_CONSTANT_MethodHandle;
1962 int kind = method_handle_ref_kind_at(idx);
1963 idx1 = method_handle_index_at(idx);
1964 *(bytes+1) = (unsigned char) kind;
1965 Bytes::put_Java_u2((address) (bytes+2), idx1);
1966 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1967 break;
1968 }
1969 case JVM_CONSTANT_MethodType:
1970 case JVM_CONSTANT_MethodTypeInError: {
1971 *bytes = JVM_CONSTANT_MethodType;
1972 idx1 = method_type_index_at(idx);
1973 Bytes::put_Java_u2((address) (bytes+1), idx1);
1974 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1975 break;
1976 }
1977 case JVM_CONSTANT_InvokeDynamic: {
1978 *bytes = tag;
1979 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1980 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1981 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1982 Bytes::put_Java_u2((address) (bytes+1), idx1);
1983 Bytes::put_Java_u2((address) (bytes+3), idx2);
1984 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1985 break;
1986 }
1987 }
1988 DBG(printf("\n"));
1989 bytes += ent_size;
1990 size += ent_size;
1991 }
1992 assert(size == cpool_size, "Size mismatch");
1993
1994 // Keep temorarily for debugging until it's stable.
1995 DBG(print_cpool_bytes(cnt, start_bytes));
1996 return (int)(bytes - start_bytes);
1997 } /* end copy_cpool_bytes */
1998
1999 #undef DBG
2000
2001
2002 void ConstantPool::set_on_stack(const bool value) {
2003 if (value) {
2004 // Only record if it's not already set.
2005 if (!on_stack()) {
2006 assert(!is_shared(), "should always be set for shared constant pools");
2007 _flags |= _on_stack;
2008 MetadataOnStackMark::record(this);
2009 }
2010 } else {
2011 // Clearing is done single-threadedly.
2012 if (!is_shared()) {
2013 _flags &= ~_on_stack;
2014 }
2015 }
2016 }
2017
2018 // JSR 292 support for patching constant pool oops after the class is linked and
2019 // the oop array for resolved references are created.
2020 // We can't do this during classfile parsing, which is how the other indexes are
2021 // patched. The other patches are applied early for some error checking
2022 // so only defer the pseudo_strings.
2023 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
2024 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
2025 Handle patch = cp_patches->at(index);
2026 if (patch.not_null()) {
2027 assert (tag_at(index).is_string(), "should only be string left");
2028 // Patching a string means pre-resolving it.
2029 // The spelling in the constant pool is ignored.
2030 // The constant reference may be any object whatever.
2031 // If it is not a real interned string, the constant is referred
2032 // to as a "pseudo-string", and must be presented to the CP
2033 // explicitly, because it may require scavenging.
2034 int obj_index = cp_to_object_index(index);
2035 pseudo_string_at_put(index, obj_index, patch());
2036 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
2037 }
2038 }
2039 #ifdef ASSERT
2040 // Ensure that all the patches have been used.
2041 for (int index = 0; index < cp_patches->length(); index++) {
2042 assert(cp_patches->at(index).is_null(),
2043 "Unused constant pool patch at %d in class file %s",
2044 index,
2045 pool_holder()->external_name());
2046 }
2047 #endif // ASSERT
2048 }
2049
2050 #ifndef PRODUCT
2051
2052 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
2053 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
2054 guarantee(obj->is_constantPool(), "object must be constant pool");
2055 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
2056 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
2057
2058 for (int i = 0; i< cp->length(); i++) {
2059 if (cp->tag_at(i).is_unresolved_klass()) {
2060 // This will force loading of the class
2061 Klass* klass = cp->klass_at(i, CHECK);
2062 if (klass->is_instance_klass()) {
2063 // Force initialization of class
2064 InstanceKlass::cast(klass)->initialize(CHECK);
2065 }
2066 }
2067 }
2068 }
2069
2070 #endif
2071
2072
2073 // Printing
2074
2075 void ConstantPool::print_on(outputStream* st) const {
2076 assert(is_constantPool(), "must be constantPool");
2077 st->print_cr("%s", internal_name());
2078 if (flags() != 0) {
2079 st->print(" - flags: 0x%x", flags());
2080 if (has_preresolution()) st->print(" has_preresolution");
2081 if (on_stack()) st->print(" on_stack");
2082 st->cr();
2083 }
2084 if (pool_holder() != NULL) {
2085 st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
2086 }
2087 st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
2088 st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
2089 st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
2090 st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
2091
2092 for (int index = 1; index < length(); index++) { // Index 0 is unused
2093 ((ConstantPool*)this)->print_entry_on(index, st);
2094 switch (tag_at(index).value()) {
2095 case JVM_CONSTANT_Long :
2096 case JVM_CONSTANT_Double :
2097 index++; // Skip entry following eigth-byte constant
2098 }
2099
2100 }
2101 st->cr();
2102 }
2103
2104 // Print one constant pool entry
2105 void ConstantPool::print_entry_on(const int index, outputStream* st) {
2106 EXCEPTION_MARK;
2107 st->print(" - %3d : ", index);
2108 tag_at(index).print_on(st);
2109 st->print(" : ");
2110 switch (tag_at(index).value()) {
2111 case JVM_CONSTANT_Class :
2112 { Klass* k = klass_at(index, CATCH);
2113 guarantee(k != NULL, "need klass");
2114 k->print_value_on(st);
2115 st->print(" {" PTR_FORMAT "}", p2i(k));
2116 }
2117 break;
2118 case JVM_CONSTANT_Fieldref :
2119 case JVM_CONSTANT_Methodref :
2120 case JVM_CONSTANT_InterfaceMethodref :
2121 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
2122 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
2123 break;
2124 case JVM_CONSTANT_String :
2125 if (is_pseudo_string_at(index)) {
2126 oop anObj = pseudo_string_at(index);
2127 anObj->print_value_on(st);
2128 st->print(" {" PTR_FORMAT "}", p2i(anObj));
2129 } else {
2130 unresolved_string_at(index)->print_value_on(st);
2131 }
2132 break;
2133 case JVM_CONSTANT_Integer :
2134 st->print("%d", int_at(index));
2135 break;
2136 case JVM_CONSTANT_Float :
2137 st->print("%f", float_at(index));
2138 break;
2139 case JVM_CONSTANT_Long :
2140 st->print_jlong(long_at(index));
2141 break;
2142 case JVM_CONSTANT_Double :
2143 st->print("%lf", double_at(index));
2144 break;
2145 case JVM_CONSTANT_NameAndType :
2146 st->print("name_index=%d", name_ref_index_at(index));
2147 st->print(" signature_index=%d", signature_ref_index_at(index));
2148 break;
2149 case JVM_CONSTANT_Utf8 :
2150 symbol_at(index)->print_value_on(st);
2151 break;
2152 case JVM_CONSTANT_ClassIndex: {
2153 int name_index = *int_at_addr(index);
2154 st->print("klass_index=%d ", name_index);
2155 symbol_at(name_index)->print_value_on(st);
2156 }
2157 break;
2158 case JVM_CONSTANT_UnresolvedClass : // fall-through
2159 case JVM_CONSTANT_UnresolvedClassInError: {
2160 CPKlassSlot kslot = klass_slot_at(index);
2161 int resolved_klass_index = kslot.resolved_klass_index();
2162 int name_index = kslot.name_index();
2163 assert(tag_at(name_index).is_symbol(), "sanity");
2164
2165 Klass* klass = resolved_klasses()->at(resolved_klass_index);
2166 if (klass != NULL) {
2167 klass->print_value_on(st);
2168 } else {
2169 symbol_at(name_index)->print_value_on(st);
2170 }
2171 }
2172 break;
2173 case JVM_CONSTANT_MethodHandle :
2174 case JVM_CONSTANT_MethodHandleInError :
2175 st->print("ref_kind=%d", method_handle_ref_kind_at(index));
2176 st->print(" ref_index=%d", method_handle_index_at(index));
2177 break;
2178 case JVM_CONSTANT_MethodType :
2179 case JVM_CONSTANT_MethodTypeInError :
2180 st->print("signature_index=%d", method_type_index_at(index));
2181 break;
2182 case JVM_CONSTANT_InvokeDynamic :
2183 {
2184 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2185 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2186 int argc = invoke_dynamic_argument_count_at(index);
2187 if (argc > 0) {
2188 for (int arg_i = 0; arg_i < argc; arg_i++) {
2189 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2190 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2191 }
2192 st->print("}");
2193 }
2194 }
2195 break;
2196 default:
2197 ShouldNotReachHere();
2198 break;
2199 }
2200 st->cr();
2201 }
2202
2203 void ConstantPool::print_value_on(outputStream* st) const {
2204 assert(is_constantPool(), "must be constantPool");
2205 st->print("constant pool [%d]", length());
2206 if (has_preresolution()) st->print("/preresolution");
2207 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2208 print_address_on(st);
2209 st->print(" for ");
2210 pool_holder()->print_value_on(st);
2211 if (pool_holder() != NULL) {
2212 bool extra = (pool_holder()->constants() != this);
2213 if (extra) st->print(" (extra)");
2214 }
2215 if (cache() != NULL) {
2216 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2217 }
2218 }
2219
2220 #if INCLUDE_SERVICES
2221 // Size Statistics
2222 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2223 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2224 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2225 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2226 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2227 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2228
2229 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2230 sz->_cp_refmap_bytes;
2231 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2232 }
2233 #endif // INCLUDE_SERVICES
2234
2235 // Verification
2236
2237 void ConstantPool::verify_on(outputStream* st) {
2238 guarantee(is_constantPool(), "object must be constant pool");
2239 for (int i = 0; i< length(); i++) {
2240 constantTag tag = tag_at(i);
2241 if (tag.is_klass() || tag.is_unresolved_klass()) {
2242 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2243 } else if (tag.is_symbol()) {
2244 CPSlot entry = slot_at(i);
2245 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2246 } else if (tag.is_string()) {
2247 CPSlot entry = slot_at(i);
2248 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2249 }
2250 }
2251 if (cache() != NULL) {
2252 // Note: cache() can be NULL before a class is completely setup or
2253 // in temporary constant pools used during constant pool merging
2254 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2255 }
2256 if (pool_holder() != NULL) {
2257 // Note: pool_holder() can be NULL in temporary constant pools
2258 // used during constant pool merging
2259 guarantee(pool_holder()->is_klass(), "should be klass");
2260 }
2261 }
2262
2263
2264 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2265 char *str = sym->as_utf8();
2266 unsigned int hash = compute_hash(str, sym->utf8_length());
2267 unsigned int index = hash % table_size();
2268
2269 // check if already in map
2270 // we prefer the first entry since it is more likely to be what was used in
2271 // the class file
2272 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2273 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2274 if (en->hash() == hash && en->symbol() == sym) {
2275 return; // already there
2276 }
2277 }
2278
2279 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2280 entry->set_next(bucket(index));
2281 _buckets[index].set_entry(entry);
2282 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2283 }
2284
2285 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2286 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2287 char *str = sym->as_utf8();
2288 int len = sym->utf8_length();
2289 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2290 unsigned int index = hash % table_size();
2291 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2292 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2293 if (en->hash() == hash && en->symbol() == sym) {
2294 return en;
2295 }
2296 }
2297 return NULL;
2298 }