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 "jvm.h"
27 #include "classfile/classLoaderData.hpp"
28 #include "classfile/javaClasses.inline.hpp"
29 #include "classfile/metadataOnStackMark.hpp"
30 #include "classfile/stringTable.hpp"
31 #include "classfile/systemDictionary.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "interpreter/linkResolver.hpp"
34 #include "memory/heapInspection.hpp"
35 #include "memory/metadataFactory.hpp"
36 #include "memory/metaspaceClosure.hpp"
37 #include "memory/metaspaceShared.hpp"
38 #include "memory/oopFactory.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "oops/constantPool.hpp"
41 #include "oops/instanceKlass.hpp"
42 #include "oops/objArrayKlass.hpp"
43 #include "oops/objArrayOop.inline.hpp"
44 #include "oops/oop.inline.hpp"
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 // Called from outside constant pool resolution where a resolved_reference array
139 // may not be present.
140 objArrayOop ConstantPool::resolved_references_or_null() const {
141 if (_cache == NULL) {
142 return NULL;
143 } else {
144 return (objArrayOop)_cache->resolved_references();
145 }
146 }
147
148 // Create resolved_references array and mapping array for original cp indexes
149 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
150 // to map it back for resolving and some unlikely miscellaneous uses.
151 // The objects created by invokedynamic are appended to this list.
152 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
153 const intStack& reference_map,
154 int constant_pool_map_length,
155 TRAPS) {
156 // Initialized the resolved object cache.
157 int map_length = reference_map.length();
158 if (map_length > 0) {
159 // Only need mapping back to constant pool entries. The map isn't used for
160 // invokedynamic resolved_reference entries. For invokedynamic entries,
161 // the constant pool cache index has the mapping back to both the constant
162 // pool and to the resolved reference index.
163 if (constant_pool_map_length > 0) {
164 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
165
166 for (int i = 0; i < constant_pool_map_length; i++) {
167 int x = reference_map.at(i);
168 assert(x == (int)(jushort) x, "klass index is too big");
169 om->at_put(i, (jushort)x);
170 }
171 set_reference_map(om);
172 }
173
174 // Create Java array for holding resolved strings, methodHandles,
175 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
176 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
177 Handle refs_handle (THREAD, (oop)stom); // must handleize.
178 set_resolved_references(loader_data->add_handle(refs_handle));
179 }
180 }
181
182 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
183 // A ConstantPool can't possibly have 0xffff valid class entries,
184 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
185 // entry for the class's name. So at most we will have 0xfffe class entries.
186 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
187 // UnresolvedKlass entries that are temporarily created during class redefinition.
188 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
189 assert(resolved_klasses() == NULL, "sanity");
190 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
191 set_resolved_klasses(rk);
192 }
193
194 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
195 int len = length();
196 int num_klasses = 0;
197 for (int i = 1; i <len; i++) {
198 switch (tag_at(i).value()) {
199 case JVM_CONSTANT_ClassIndex:
200 {
201 const int class_index = klass_index_at(i);
202 unresolved_klass_at_put(i, class_index, num_klasses++);
203 }
204 break;
205 #ifndef PRODUCT
206 case JVM_CONSTANT_Class:
207 case JVM_CONSTANT_UnresolvedClass:
208 case JVM_CONSTANT_UnresolvedClassInError:
209 // All of these should have been reverted back to ClassIndex before calling
210 // this function.
211 ShouldNotReachHere();
212 #endif
213 }
214 }
215 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
216 }
217
218 // Anonymous class support:
219 void ConstantPool::klass_at_put(int class_index, int name_index, int resolved_klass_index, Klass* k, Symbol* name) {
220 assert(is_within_bounds(class_index), "index out of bounds");
221 assert(is_within_bounds(name_index), "index out of bounds");
222 assert((resolved_klass_index & 0xffff0000) == 0, "must be");
223 *int_at_addr(class_index) =
224 build_int_from_shorts((jushort)resolved_klass_index, (jushort)name_index);
225
226 symbol_at_put(name_index, name);
227 name->increment_refcount();
228 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
229 OrderAccess::release_store(adr, k);
230
231 // The interpreter assumes when the tag is stored, the klass is resolved
232 // and the Klass* non-NULL, so we need hardware store ordering here.
233 if (k != NULL) {
234 release_tag_at_put(class_index, JVM_CONSTANT_Class);
235 } else {
236 release_tag_at_put(class_index, JVM_CONSTANT_UnresolvedClass);
237 }
238 }
239
240 // Anonymous class support:
241 void ConstantPool::klass_at_put(int class_index, Klass* k) {
242 assert(k != NULL, "must be valid klass");
243 CPKlassSlot kslot = klass_slot_at(class_index);
244 int resolved_klass_index = kslot.resolved_klass_index();
245 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
246 OrderAccess::release_store(adr, k);
247
248 // The interpreter assumes when the tag is stored, the klass is resolved
249 // and the Klass* non-NULL, so we need hardware store ordering here.
250 release_tag_at_put(class_index, JVM_CONSTANT_Class);
251 }
252
253 #if INCLUDE_CDS_JAVA_HEAP
254 // Archive the resolved references
255 void ConstantPool::archive_resolved_references(Thread* THREAD) {
256 if (_cache == NULL) {
257 return; // nothing to do
258 }
259
260 InstanceKlass *ik = pool_holder();
261 if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
262 ik->is_shared_app_class())) {
263 // Archiving resolved references for classes from non-builtin loaders
264 // is not yet supported.
265 set_resolved_references(NULL);
266 return;
267 }
268
269 objArrayOop rr = resolved_references();
270 Array<u2>* ref_map = reference_map();
271 if (rr != NULL) {
272 int ref_map_len = ref_map == NULL ? 0 : ref_map->length();
273 int rr_len = rr->length();
274 for (int i = 0; i < rr_len; i++) {
275 oop p = rr->obj_at(i);
276 rr->obj_at_put(i, NULL);
277 if (p != NULL && i < ref_map_len) {
278 int index = object_to_cp_index(i);
279 // Skip the entry if the string hash code is 0 since the string
280 // is not included in the shared string_table, see StringTable::copy_shared_string.
281 if (tag_at(index).is_string() && java_lang_String::hash_code(p) != 0) {
282 oop op = StringTable::create_archived_string(p, THREAD);
283 // If the String object is not archived (possibly too large),
284 // NULL is returned. Also set it in the array, so we won't
285 // have a 'bad' reference in the archived resolved_reference
286 // array.
287 rr->obj_at_put(i, op);
288 }
289 }
290 }
291
292 oop archived = MetaspaceShared::archive_heap_object(rr, THREAD);
293 _cache->set_archived_references(archived);
294 set_resolved_references(NULL);
295 }
296 }
297
298 void ConstantPool::resolve_class_constants(TRAPS) {
299 assert(DumpSharedSpaces, "used during dump time only");
300 // The _cache may be NULL if the _pool_holder klass fails verification
301 // at dump time due to missing dependencies.
302 if (cache() == NULL || reference_map() == NULL) {
303 return; // nothing to do
304 }
305
306 constantPoolHandle cp(THREAD, this);
307 for (int index = 1; index < length(); index++) { // Index 0 is unused
308 if (tag_at(index).is_string() && !cp->is_pseudo_string_at(index)) {
309 int cache_index = cp->cp_to_object_index(index);
310 string_at_impl(cp, index, cache_index, CHECK);
311 }
312 }
313 }
314 #endif
315
316 // CDS support. Create a new resolved_references array.
317 void ConstantPool::restore_unshareable_info(TRAPS) {
318 assert(is_constantPool(), "ensure C++ vtable is restored");
319 assert(on_stack(), "should always be set for shared constant pools");
320 assert(is_shared(), "should always be set for shared constant pools");
321 assert(_cache != NULL, "constant pool _cache should not be NULL");
322
323 // Only create the new resolved references array if it hasn't been attempted before
324 if (resolved_references() != NULL) return;
325
326 // restore the C++ vtable from the shared archive
327 restore_vtable();
328
329 if (SystemDictionary::Object_klass_loaded()) {
330 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
331 #if INCLUDE_CDS_JAVA_HEAP
332 if (MetaspaceShared::open_archive_heap_region_mapped() &&
333 _cache->archived_references() != NULL) {
334 oop archived = _cache->archived_references();
335 // Make sure GC knows the cached object is now live. This is necessary after
336 // initial GC marking and during concurrent marking as strong roots are only
337 // scanned during initial marking (at the start of the GC marking).
338 assert(UseG1GC, "Requires G1 GC");
339 G1SATBCardTableModRefBS::enqueue(archived);
340 // Create handle for the archived resolved reference array object
341 Handle refs_handle(THREAD, (oop)archived);
342 set_resolved_references(loader_data->add_handle(refs_handle));
343 } else
344 #endif
345 {
346 // No mapped archived resolved reference array
347 // Recreate the object array and add to ClassLoaderData.
348 int map_length = resolved_reference_length();
349 if (map_length > 0) {
350 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
351 Handle refs_handle(THREAD, (oop)stom); // must handleize.
352 set_resolved_references(loader_data->add_handle(refs_handle));
353 }
354 }
355 }
356 }
357
358 void ConstantPool::remove_unshareable_info() {
359 // Resolved references are not in the shared archive.
360 // Save the length for restoration. It is not necessarily the same length
361 // as reference_map.length() if invokedynamic is saved. It is needed when
362 // re-creating the resolved reference array if archived heap data cannot be map
363 // at runtime.
364 set_resolved_reference_length(
365 resolved_references() != NULL ? resolved_references()->length() : 0);
366
367 // If archiving heap objects is not allowed, clear the resolved references.
368 // Otherwise, it is cleared after the resolved references array is cached
369 // (see archive_resolved_references()).
370 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
371 set_resolved_references(NULL);
372 }
373
374 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
375 // The _on_stack flag is used to prevent ConstantPools from deallocation during
376 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
377 // we always set _on_stack to true to avoid having to change _flags during runtime.
378 _flags |= (_on_stack | _is_shared);
379 int num_klasses = 0;
380 for (int index = 1; index < length(); index++) { // Index 0 is unused
381 assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
382 if (tag_at(index).is_klass()) {
383 // This class was resolved as a side effect of executing Java code
384 // during dump time. We need to restore it back to an UnresolvedClass,
385 // so that the proper class loading and initialization can happen
386 // at runtime.
387 CPKlassSlot kslot = klass_slot_at(index);
388 int resolved_klass_index = kslot.resolved_klass_index();
389 int name_index = kslot.name_index();
390 assert(tag_at(name_index).is_symbol(), "sanity");
391 resolved_klasses()->at_put(resolved_klass_index, NULL);
392 tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
393 assert(klass_name_at(index) == symbol_at(name_index), "sanity");
394 }
395 }
396 if (cache() != NULL) {
397 cache()->remove_unshareable_info();
398 }
399 }
400
401 int ConstantPool::cp_to_object_index(int cp_index) {
402 // this is harder don't do this so much.
403 int i = reference_map()->find(cp_index);
404 // We might not find the index for jsr292 call.
405 return (i < 0) ? _no_index_sentinel : i;
406 }
407
408 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
409 resolved_references()->obj_at_put(obj_index, str);
410 }
411
412 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
413 ResourceMark rm;
414 int line_number = -1;
415 const char * source_file = NULL;
416 if (JavaThread::current()->has_last_Java_frame()) {
417 // try to identify the method which called this function.
418 vframeStream vfst(JavaThread::current());
419 if (!vfst.at_end()) {
420 line_number = vfst.method()->line_number_from_bci(vfst.bci());
421 Symbol* s = vfst.method()->method_holder()->source_file_name();
422 if (s != NULL) {
423 source_file = s->as_C_string();
424 }
425 }
426 }
427 if (k != this_cp->pool_holder()) {
428 // only print something if the classes are different
429 if (source_file != NULL) {
430 log_debug(class, resolve)("%s %s %s:%d",
431 this_cp->pool_holder()->external_name(),
432 k->external_name(), source_file, line_number);
433 } else {
434 log_debug(class, resolve)("%s %s",
435 this_cp->pool_holder()->external_name(),
436 k->external_name());
437 }
438 }
439 }
440
441 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
442 bool save_resolution_error, TRAPS) {
443 assert(THREAD->is_Java_thread(), "must be a Java thread");
444
445 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
446 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
447 // the entry and tag is not updated atomicly.
448 CPKlassSlot kslot = this_cp->klass_slot_at(which);
449 int resolved_klass_index = kslot.resolved_klass_index();
450 int name_index = kslot.name_index();
451 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
452
453 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
454 if (klass != NULL) {
455 return klass;
456 }
457
458 // This tag doesn't change back to unresolved class unless at a safepoint.
459 if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
460 // The original attempt to resolve this constant pool entry failed so find the
461 // class of the original error and throw another error of the same class
462 // (JVMS 5.4.3).
463 // If there is a detail message, pass that detail message to the error.
464 // The JVMS does not strictly require us to duplicate the same detail message,
465 // or any internal exception fields such as cause or stacktrace. But since the
466 // detail message is often a class name or other literal string, we will repeat it
467 // if we can find it in the symbol table.
468 throw_resolution_error(this_cp, which, CHECK_0);
469 ShouldNotReachHere();
470 }
471
472 Handle mirror_handle;
473 Symbol* name = this_cp->symbol_at(name_index);
474 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
475 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
476 Klass* k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
477 if (!HAS_PENDING_EXCEPTION) {
478 // preserve the resolved klass from unloading
479 mirror_handle = Handle(THREAD, k->java_mirror());
480 // Do access check for klasses
481 verify_constant_pool_resolve(this_cp, k, THREAD);
482 }
483
484 // Failed to resolve class. We must record the errors so that subsequent attempts
485 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
486 if (HAS_PENDING_EXCEPTION) {
487 if (save_resolution_error) {
488 save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
489 // If CHECK_NULL above doesn't return the exception, that means that
490 // some other thread has beaten us and has resolved the class.
491 // To preserve old behavior, we return the resolved class.
492 klass = this_cp->resolved_klasses()->at(resolved_klass_index);
493 assert(klass != NULL, "must be resolved if exception was cleared");
494 return klass;
495 } else {
496 return NULL; // return the pending exception
497 }
498 }
499
500 // Make this class loader depend upon the class loader owning the class reference
501 ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
502 this_key->record_dependency(k, CHECK_NULL); // Can throw OOM
503
504 // logging for class+resolve.
505 if (log_is_enabled(Debug, class, resolve)){
506 trace_class_resolution(this_cp, k);
507 }
508 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
509 OrderAccess::release_store(adr, k);
510 // The interpreter assumes when the tag is stored, the klass is resolved
511 // and the Klass* stored in _resolved_klasses is non-NULL, so we need
512 // hardware store ordering here.
513 this_cp->release_tag_at_put(which, JVM_CONSTANT_Class);
514 return k;
515 }
516
517
518 // Does not update ConstantPool* - to avoid any exception throwing. Used
519 // by compiler and exception handling. Also used to avoid classloads for
520 // instanceof operations. Returns NULL if the class has not been loaded or
521 // if the verification of constant pool failed
522 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
523 CPKlassSlot kslot = this_cp->klass_slot_at(which);
524 int resolved_klass_index = kslot.resolved_klass_index();
525 int name_index = kslot.name_index();
526 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
527
528 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
529 if (k != NULL) {
530 return k;
531 } else {
532 Thread *thread = Thread::current();
533 Symbol* name = this_cp->symbol_at(name_index);
534 oop loader = this_cp->pool_holder()->class_loader();
535 oop protection_domain = this_cp->pool_holder()->protection_domain();
536 Handle h_prot (thread, protection_domain);
537 Handle h_loader (thread, loader);
538 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
539
540 if (k != NULL) {
541 // Make sure that resolving is legal
542 EXCEPTION_MARK;
543 // return NULL if verification fails
544 verify_constant_pool_resolve(this_cp, k, THREAD);
545 if (HAS_PENDING_EXCEPTION) {
546 CLEAR_PENDING_EXCEPTION;
547 return NULL;
548 }
549 return k;
550 } else {
551 return k;
552 }
553 }
554 }
555
556
557 Klass* ConstantPool::klass_ref_at_if_loaded(const constantPoolHandle& this_cp, int which) {
558 return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
559 }
560
561
562 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
563 int which) {
564 if (cpool->cache() == NULL) return NULL; // nothing to load yet
565 int cache_index = decode_cpcache_index(which, true);
566 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
567 // FIXME: should be an assert
568 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
569 return NULL;
570 }
571 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
572 return e->method_if_resolved(cpool);
573 }
574
575
576 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
577 if (cpool->cache() == NULL) return false; // nothing to load yet
578 int cache_index = decode_cpcache_index(which, true);
579 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
580 return e->has_appendix();
581 }
582
583 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
584 if (cpool->cache() == NULL) return NULL; // nothing to load yet
585 int cache_index = decode_cpcache_index(which, true);
586 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
587 return e->appendix_if_resolved(cpool);
588 }
589
590
591 bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
592 if (cpool->cache() == NULL) return false; // nothing to load yet
593 int cache_index = decode_cpcache_index(which, true);
594 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
595 return e->has_method_type();
596 }
597
598 oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
599 if (cpool->cache() == NULL) return NULL; // nothing to load yet
600 int cache_index = decode_cpcache_index(which, true);
601 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
602 return e->method_type_if_resolved(cpool);
603 }
604
605
606 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
607 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
608 return symbol_at(name_index);
609 }
610
611
612 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
613 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
614 return symbol_at(signature_index);
615 }
616
617
618 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
619 int i = which;
620 if (!uncached && cache() != NULL) {
621 if (ConstantPool::is_invokedynamic_index(which)) {
622 // Invokedynamic index is index into the constant pool cache
623 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
624 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
625 assert(tag_at(pool_index).is_name_and_type(), "");
626 return pool_index;
627 }
628 // change byte-ordering and go via cache
629 i = remap_instruction_operand_from_cache(which);
630 } else {
631 if (tag_at(which).is_invoke_dynamic()) {
632 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
633 assert(tag_at(pool_index).is_name_and_type(), "");
634 return pool_index;
635 }
636 }
637 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
638 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
639 jint ref_index = *int_at_addr(i);
640 return extract_high_short_from_int(ref_index);
641 }
642
643 constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
644 int pool_index = which;
645 if (!uncached && cache() != NULL) {
646 if (ConstantPool::is_invokedynamic_index(which)) {
647 // Invokedynamic index is index into resolved_references
648 pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
649 } else {
650 // change byte-ordering and go via cache
651 pool_index = remap_instruction_operand_from_cache(which);
652 }
653 }
654 return tag_at(pool_index);
655 }
656
657 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
658 guarantee(!ConstantPool::is_invokedynamic_index(which),
659 "an invokedynamic instruction does not have a klass");
660 int i = which;
661 if (!uncached && cache() != NULL) {
662 // change byte-ordering and go via cache
663 i = remap_instruction_operand_from_cache(which);
664 }
665 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
666 jint ref_index = *int_at_addr(i);
667 return extract_low_short_from_int(ref_index);
668 }
669
670
671
672 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
673 int cpc_index = operand;
674 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
675 assert((int)(u2)cpc_index == cpc_index, "clean u2");
676 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
677 return member_index;
678 }
679
680
681 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
682 if (k->is_instance_klass() || k->is_objArray_klass()) {
683 InstanceKlass* holder = this_cp->pool_holder();
684 Klass* elem = k->is_instance_klass() ? k : ObjArrayKlass::cast(k)->bottom_klass();
685
686 // The element type could be a typeArray - we only need the access check if it is
687 // an reference to another class
688 if (elem->is_instance_klass()) {
689 LinkResolver::check_klass_accessability(holder, elem, CHECK);
690 }
691 }
692 }
693
694
695 int ConstantPool::name_ref_index_at(int which_nt) {
696 jint ref_index = name_and_type_at(which_nt);
697 return extract_low_short_from_int(ref_index);
698 }
699
700
701 int ConstantPool::signature_ref_index_at(int which_nt) {
702 jint ref_index = name_and_type_at(which_nt);
703 return extract_high_short_from_int(ref_index);
704 }
705
706
707 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
708 return klass_at(klass_ref_index_at(which), THREAD);
709 }
710
711 Symbol* ConstantPool::klass_name_at(int which) const {
712 return symbol_at(klass_slot_at(which).name_index());
713 }
714
715 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
716 jint ref_index = klass_ref_index_at(which);
717 return klass_at_noresolve(ref_index);
718 }
719
720 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
721 jint ref_index = uncached_klass_ref_index_at(which);
722 return klass_at_noresolve(ref_index);
723 }
724
725 char* ConstantPool::string_at_noresolve(int which) {
726 return unresolved_string_at(which)->as_C_string();
727 }
728
729 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
730 return FieldType::basic_type(symbol_at(which));
731 }
732
733
734 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
735 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
736 if (this_cp->tag_at(index).is_string()) {
737 this_cp->string_at(index, CHECK);
738 }
739 }
740 }
741
742 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
743 // Dig out the detailed message to reuse if possible
744 Symbol* message = java_lang_Throwable::detail_message(pending_exception);
745 if (message != NULL) {
746 return message;
747 }
748
749 // Return specific message for the tag
750 switch (tag.value()) {
751 case JVM_CONSTANT_UnresolvedClass:
752 // return the class name in the error message
753 message = this_cp->klass_name_at(which);
754 break;
755 case JVM_CONSTANT_MethodHandle:
756 // return the method handle name in the error message
757 message = this_cp->method_handle_name_ref_at(which);
758 break;
759 case JVM_CONSTANT_MethodType:
760 // return the method type signature in the error message
761 message = this_cp->method_type_signature_at(which);
762 break;
763 default:
764 ShouldNotReachHere();
765 }
766
767 return message;
768 }
769
770 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
771 Symbol* message = NULL;
772 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
773 assert(error != NULL && message != NULL, "checking");
774 CLEAR_PENDING_EXCEPTION;
775 ResourceMark rm;
776 THROW_MSG(error, message->as_C_string());
777 }
778
779 // If resolution for Class, MethodHandle or MethodType fails, save the exception
780 // in the resolution error table, so that the same exception is thrown again.
781 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
782 constantTag tag, TRAPS) {
783 Symbol* error = PENDING_EXCEPTION->klass()->name();
784
785 int error_tag = tag.error_value();
786
787 if (!PENDING_EXCEPTION->
788 is_a(SystemDictionary::LinkageError_klass())) {
789 // Just throw the exception and don't prevent these classes from
790 // being loaded due to virtual machine errors like StackOverflow
791 // and OutOfMemoryError, etc, or if the thread was hit by stop()
792 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
793 } else if (this_cp->tag_at(which).value() != error_tag) {
794 Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
795 SystemDictionary::add_resolution_error(this_cp, which, error, message);
796 // CAS in the tag. If a thread beat us to registering this error that's fine.
797 // If another thread resolved the reference, this is a race condition. This
798 // thread may have had a security manager or something temporary.
799 // This doesn't deterministically get an error. So why do we save this?
800 // We save this because jvmti can add classes to the bootclass path after
801 // this error, so it needs to get the same error if the error is first.
802 jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
803 (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
804 if (old_tag != error_tag && old_tag != tag.value()) {
805 // MethodHandles and MethodType doesn't change to resolved version.
806 assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
807 // Forget the exception and use the resolved class.
808 CLEAR_PENDING_EXCEPTION;
809 }
810 } else {
811 // some other thread put this in error state
812 throw_resolution_error(this_cp, which, CHECK);
813 }
814 }
815
816 // Called to resolve constants in the constant pool and return an oop.
817 // Some constant pool entries cache their resolved oop. This is also
818 // called to create oops from constants to use in arguments for invokedynamic
819 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS) {
820 oop result_oop = NULL;
821 Handle throw_exception;
822
823 if (cache_index == _possible_index_sentinel) {
824 // It is possible that this constant is one which is cached in the objects.
825 // We'll do a linear search. This should be OK because this usage is rare.
826 assert(index > 0, "valid index");
827 cache_index = this_cp->cp_to_object_index(index);
828 }
829 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
830 assert(index == _no_index_sentinel || index >= 0, "");
831
832 if (cache_index >= 0) {
833 result_oop = this_cp->resolved_references()->obj_at(cache_index);
834 if (result_oop != NULL) {
835 return result_oop;
836 // That was easy...
837 }
838 index = this_cp->object_to_cp_index(cache_index);
839 }
840
841 jvalue prim_value; // temp used only in a few cases below
842
843 constantTag tag = this_cp->tag_at(index);
844
845 switch (tag.value()) {
846
847 case JVM_CONSTANT_UnresolvedClass:
848 case JVM_CONSTANT_UnresolvedClassInError:
849 case JVM_CONSTANT_Class:
850 {
851 assert(cache_index == _no_index_sentinel, "should not have been set");
852 Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
853 // ldc wants the java mirror.
854 result_oop = resolved->java_mirror();
855 break;
856 }
857
858 case JVM_CONSTANT_String:
859 assert(cache_index != _no_index_sentinel, "should have been set");
860 if (this_cp->is_pseudo_string_at(index)) {
861 result_oop = this_cp->pseudo_string_at(index, cache_index);
862 break;
863 }
864 result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
865 break;
866
867 case JVM_CONSTANT_MethodHandleInError:
868 case JVM_CONSTANT_MethodTypeInError:
869 {
870 throw_resolution_error(this_cp, index, CHECK_NULL);
871 break;
872 }
873
874 case JVM_CONSTANT_MethodHandle:
875 {
876 int ref_kind = this_cp->method_handle_ref_kind_at(index);
877 int callee_index = this_cp->method_handle_klass_index_at(index);
878 Symbol* name = this_cp->method_handle_name_ref_at(index);
879 Symbol* signature = this_cp->method_handle_signature_ref_at(index);
880 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(index));
881 { ResourceMark rm(THREAD);
882 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
883 ref_kind, index, this_cp->method_handle_index_at(index),
884 callee_index, name->as_C_string(), signature->as_C_string());
885 }
886
887 Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
888
889 // Check constant pool method consistency
890 if ((callee->is_interface() && m_tag.is_method()) ||
891 ((!callee->is_interface() && m_tag.is_interface_method()))) {
892 ResourceMark rm(THREAD);
893 char buf[400];
894 jio_snprintf(buf, sizeof(buf),
895 "Inconsistent constant pool data in classfile for class %s. "
896 "Method %s%s at index %d is %s and should be %s",
897 callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
898 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
899 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
900 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
901 }
902
903 Klass* klass = this_cp->pool_holder();
904 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
905 callee, name, signature,
906 THREAD);
907 result_oop = value();
908 if (HAS_PENDING_EXCEPTION) {
909 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
910 }
911 break;
912 }
913
914 case JVM_CONSTANT_MethodType:
915 {
916 Symbol* signature = this_cp->method_type_signature_at(index);
917 { ResourceMark rm(THREAD);
918 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
919 index, this_cp->method_type_index_at(index),
920 signature->as_C_string());
921 }
922 Klass* klass = this_cp->pool_holder();
923 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
924 result_oop = value();
925 if (HAS_PENDING_EXCEPTION) {
926 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
927 }
928 break;
929 }
930
931 case JVM_CONSTANT_Integer:
932 assert(cache_index == _no_index_sentinel, "should not have been set");
933 prim_value.i = this_cp->int_at(index);
934 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
935 break;
936
937 case JVM_CONSTANT_Float:
938 assert(cache_index == _no_index_sentinel, "should not have been set");
939 prim_value.f = this_cp->float_at(index);
940 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
941 break;
942
943 case JVM_CONSTANT_Long:
944 assert(cache_index == _no_index_sentinel, "should not have been set");
945 prim_value.j = this_cp->long_at(index);
946 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
947 break;
948
949 case JVM_CONSTANT_Double:
950 assert(cache_index == _no_index_sentinel, "should not have been set");
951 prim_value.d = this_cp->double_at(index);
952 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
953 break;
954
955 default:
956 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
957 this_cp(), index, cache_index, tag.value()));
958 assert(false, "unexpected constant tag");
959 break;
960 }
961
962 if (cache_index >= 0) {
963 // Benign race condition: resolved_references may already be filled in.
964 // The important thing here is that all threads pick up the same result.
965 // It doesn't matter which racing thread wins, as long as only one
966 // result is used by all threads, and all future queries.
967 oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
968 if (old_result == NULL) {
969 return result_oop; // was installed
970 } else {
971 // Return the winning thread's result. This can be different than
972 // the result here for MethodHandles.
973 return old_result;
974 }
975 } else {
976 return result_oop;
977 }
978 }
979
980 oop ConstantPool::uncached_string_at(int which, TRAPS) {
981 Symbol* sym = unresolved_string_at(which);
982 oop str = StringTable::intern(sym, CHECK_(NULL));
983 assert(java_lang_String::is_instance(str), "must be string");
984 return str;
985 }
986
987
988 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
989 assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
990
991 Handle bsm;
992 int argc;
993 {
994 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
995 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
996 // It is accompanied by the optional arguments.
997 int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
998 oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
999 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
1000 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
1001 }
1002
1003 // Extract the optional static arguments.
1004 argc = this_cp->invoke_dynamic_argument_count_at(index);
1005 if (argc == 0) return bsm_oop;
1006
1007 bsm = Handle(THREAD, bsm_oop);
1008 }
1009
1010 objArrayHandle info;
1011 {
1012 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
1013 info = objArrayHandle(THREAD, info_oop);
1014 }
1015
1016 info->obj_at_put(0, bsm());
1017 for (int i = 0; i < argc; i++) {
1018 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1019 oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
1020 info->obj_at_put(1+i, arg_oop);
1021 }
1022
1023 return info();
1024 }
1025
1026 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
1027 // If the string has already been interned, this entry will be non-null
1028 oop str = this_cp->resolved_references()->obj_at(obj_index);
1029 if (str != NULL) return str;
1030 Symbol* sym = this_cp->unresolved_string_at(which);
1031 str = StringTable::intern(sym, CHECK_(NULL));
1032 this_cp->string_at_put(which, obj_index, str);
1033 assert(java_lang_String::is_instance(str), "must be string");
1034 return str;
1035 }
1036
1037
1038 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
1039 // Names are interned, so we can compare Symbol*s directly
1040 Symbol* cp_name = klass_name_at(which);
1041 return (cp_name == k->name());
1042 }
1043
1044
1045 // Iterate over symbols and decrement ones which are Symbol*s
1046 // This is done during GC.
1047 // Only decrement the UTF8 symbols. Strings point to
1048 // these symbols but didn't increment the reference count.
1049 void ConstantPool::unreference_symbols() {
1050 for (int index = 1; index < length(); index++) { // Index 0 is unused
1051 constantTag tag = tag_at(index);
1052 if (tag.is_symbol()) {
1053 symbol_at(index)->decrement_refcount();
1054 }
1055 }
1056 }
1057
1058
1059 // Compare this constant pool's entry at index1 to the constant pool
1060 // cp2's entry at index2.
1061 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1062 int index2, TRAPS) {
1063
1064 // The error tags are equivalent to non-error tags when comparing
1065 jbyte t1 = tag_at(index1).non_error_value();
1066 jbyte t2 = cp2->tag_at(index2).non_error_value();
1067
1068 if (t1 != t2) {
1069 // Not the same entry type so there is nothing else to check. Note
1070 // that this style of checking will consider resolved/unresolved
1071 // class pairs as different.
1072 // From the ConstantPool* API point of view, this is correct
1073 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1074 // plays out in the context of ConstantPool* merging.
1075 return false;
1076 }
1077
1078 switch (t1) {
1079 case JVM_CONSTANT_Class:
1080 {
1081 Klass* k1 = klass_at(index1, CHECK_false);
1082 Klass* k2 = cp2->klass_at(index2, CHECK_false);
1083 if (k1 == k2) {
1084 return true;
1085 }
1086 } break;
1087
1088 case JVM_CONSTANT_ClassIndex:
1089 {
1090 int recur1 = klass_index_at(index1);
1091 int recur2 = cp2->klass_index_at(index2);
1092 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1093 if (match) {
1094 return true;
1095 }
1096 } break;
1097
1098 case JVM_CONSTANT_Double:
1099 {
1100 jdouble d1 = double_at(index1);
1101 jdouble d2 = cp2->double_at(index2);
1102 if (d1 == d2) {
1103 return true;
1104 }
1105 } break;
1106
1107 case JVM_CONSTANT_Fieldref:
1108 case JVM_CONSTANT_InterfaceMethodref:
1109 case JVM_CONSTANT_Methodref:
1110 {
1111 int recur1 = uncached_klass_ref_index_at(index1);
1112 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1113 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1114 if (match) {
1115 recur1 = uncached_name_and_type_ref_index_at(index1);
1116 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1117 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1118 if (match) {
1119 return true;
1120 }
1121 }
1122 } break;
1123
1124 case JVM_CONSTANT_Float:
1125 {
1126 jfloat f1 = float_at(index1);
1127 jfloat f2 = cp2->float_at(index2);
1128 if (f1 == f2) {
1129 return true;
1130 }
1131 } break;
1132
1133 case JVM_CONSTANT_Integer:
1134 {
1135 jint i1 = int_at(index1);
1136 jint i2 = cp2->int_at(index2);
1137 if (i1 == i2) {
1138 return true;
1139 }
1140 } break;
1141
1142 case JVM_CONSTANT_Long:
1143 {
1144 jlong l1 = long_at(index1);
1145 jlong l2 = cp2->long_at(index2);
1146 if (l1 == l2) {
1147 return true;
1148 }
1149 } break;
1150
1151 case JVM_CONSTANT_NameAndType:
1152 {
1153 int recur1 = name_ref_index_at(index1);
1154 int recur2 = cp2->name_ref_index_at(index2);
1155 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1156 if (match) {
1157 recur1 = signature_ref_index_at(index1);
1158 recur2 = cp2->signature_ref_index_at(index2);
1159 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1160 if (match) {
1161 return true;
1162 }
1163 }
1164 } break;
1165
1166 case JVM_CONSTANT_StringIndex:
1167 {
1168 int recur1 = string_index_at(index1);
1169 int recur2 = cp2->string_index_at(index2);
1170 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1171 if (match) {
1172 return true;
1173 }
1174 } break;
1175
1176 case JVM_CONSTANT_UnresolvedClass:
1177 {
1178 Symbol* k1 = klass_name_at(index1);
1179 Symbol* k2 = cp2->klass_name_at(index2);
1180 if (k1 == k2) {
1181 return true;
1182 }
1183 } break;
1184
1185 case JVM_CONSTANT_MethodType:
1186 {
1187 int k1 = method_type_index_at(index1);
1188 int k2 = cp2->method_type_index_at(index2);
1189 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1190 if (match) {
1191 return true;
1192 }
1193 } break;
1194
1195 case JVM_CONSTANT_MethodHandle:
1196 {
1197 int k1 = method_handle_ref_kind_at(index1);
1198 int k2 = cp2->method_handle_ref_kind_at(index2);
1199 if (k1 == k2) {
1200 int i1 = method_handle_index_at(index1);
1201 int i2 = cp2->method_handle_index_at(index2);
1202 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1203 if (match) {
1204 return true;
1205 }
1206 }
1207 } break;
1208
1209 case JVM_CONSTANT_InvokeDynamic:
1210 {
1211 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1212 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1213 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1214 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1215 // separate statements and variables because CHECK_false is used
1216 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1217 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1218 return (match_entry && match_operand);
1219 } break;
1220
1221 case JVM_CONSTANT_String:
1222 {
1223 Symbol* s1 = unresolved_string_at(index1);
1224 Symbol* s2 = cp2->unresolved_string_at(index2);
1225 if (s1 == s2) {
1226 return true;
1227 }
1228 } break;
1229
1230 case JVM_CONSTANT_Utf8:
1231 {
1232 Symbol* s1 = symbol_at(index1);
1233 Symbol* s2 = cp2->symbol_at(index2);
1234 if (s1 == s2) {
1235 return true;
1236 }
1237 } break;
1238
1239 // Invalid is used as the tag for the second constant pool entry
1240 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1241 // not be seen by itself.
1242 case JVM_CONSTANT_Invalid: // fall through
1243
1244 default:
1245 ShouldNotReachHere();
1246 break;
1247 }
1248
1249 return false;
1250 } // end compare_entry_to()
1251
1252
1253 // Resize the operands array with delta_len and delta_size.
1254 // Used in RedefineClasses for CP merge.
1255 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1256 int old_len = operand_array_length(operands());
1257 int new_len = old_len + delta_len;
1258 int min_len = (delta_len > 0) ? old_len : new_len;
1259
1260 int old_size = operands()->length();
1261 int new_size = old_size + delta_size;
1262 int min_size = (delta_size > 0) ? old_size : new_size;
1263
1264 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1265 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1266
1267 // Set index in the resized array for existing elements only
1268 for (int idx = 0; idx < min_len; idx++) {
1269 int offset = operand_offset_at(idx); // offset in original array
1270 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1271 }
1272 // Copy the bootstrap specifiers only
1273 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1274 new_ops->adr_at(2*new_len),
1275 (min_size - 2*min_len) * sizeof(u2));
1276 // Explicitly deallocate old operands array.
1277 // Note, it is not needed for 7u backport.
1278 if ( operands() != NULL) { // the safety check
1279 MetadataFactory::free_array<u2>(loader_data, operands());
1280 }
1281 set_operands(new_ops);
1282 } // end resize_operands()
1283
1284
1285 // Extend the operands array with the length and size of the ext_cp operands.
1286 // Used in RedefineClasses for CP merge.
1287 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1288 int delta_len = operand_array_length(ext_cp->operands());
1289 if (delta_len == 0) {
1290 return; // nothing to do
1291 }
1292 int delta_size = ext_cp->operands()->length();
1293
1294 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1295
1296 if (operand_array_length(operands()) == 0) {
1297 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1298 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1299 // The first element index defines the offset of second part
1300 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1301 set_operands(new_ops);
1302 } else {
1303 resize_operands(delta_len, delta_size, CHECK);
1304 }
1305
1306 } // end extend_operands()
1307
1308
1309 // Shrink the operands array to a smaller array with new_len length.
1310 // Used in RedefineClasses for CP merge.
1311 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1312 int old_len = operand_array_length(operands());
1313 if (new_len == old_len) {
1314 return; // nothing to do
1315 }
1316 assert(new_len < old_len, "shrunken operands array must be smaller");
1317
1318 int free_base = operand_next_offset_at(new_len - 1);
1319 int delta_len = new_len - old_len;
1320 int delta_size = 2*delta_len + free_base - operands()->length();
1321
1322 resize_operands(delta_len, delta_size, CHECK);
1323
1324 } // end shrink_operands()
1325
1326
1327 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1328 const constantPoolHandle& to_cp,
1329 TRAPS) {
1330
1331 int from_oplen = operand_array_length(from_cp->operands());
1332 int old_oplen = operand_array_length(to_cp->operands());
1333 if (from_oplen != 0) {
1334 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1335 // append my operands to the target's operands array
1336 if (old_oplen == 0) {
1337 // Can't just reuse from_cp's operand list because of deallocation issues
1338 int len = from_cp->operands()->length();
1339 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1340 Copy::conjoint_memory_atomic(
1341 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1342 to_cp->set_operands(new_ops);
1343 } else {
1344 int old_len = to_cp->operands()->length();
1345 int from_len = from_cp->operands()->length();
1346 int old_off = old_oplen * sizeof(u2);
1347 int from_off = from_oplen * sizeof(u2);
1348 // Use the metaspace for the destination constant pool
1349 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1350 int fillp = 0, len = 0;
1351 // first part of dest
1352 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1353 new_operands->adr_at(fillp),
1354 (len = old_off) * sizeof(u2));
1355 fillp += len;
1356 // first part of src
1357 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1358 new_operands->adr_at(fillp),
1359 (len = from_off) * sizeof(u2));
1360 fillp += len;
1361 // second part of dest
1362 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1363 new_operands->adr_at(fillp),
1364 (len = old_len - old_off) * sizeof(u2));
1365 fillp += len;
1366 // second part of src
1367 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1368 new_operands->adr_at(fillp),
1369 (len = from_len - from_off) * sizeof(u2));
1370 fillp += len;
1371 assert(fillp == new_operands->length(), "");
1372
1373 // Adjust indexes in the first part of the copied operands array.
1374 for (int j = 0; j < from_oplen; j++) {
1375 int offset = operand_offset_at(new_operands, old_oplen + j);
1376 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1377 offset += old_len; // every new tuple is preceded by old_len extra u2's
1378 operand_offset_at_put(new_operands, old_oplen + j, offset);
1379 }
1380
1381 // replace target operands array with combined array
1382 to_cp->set_operands(new_operands);
1383 }
1384 }
1385 } // end copy_operands()
1386
1387
1388 // Copy this constant pool's entries at start_i to end_i (inclusive)
1389 // to the constant pool to_cp's entries starting at to_i. A total of
1390 // (end_i - start_i) + 1 entries are copied.
1391 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1392 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1393
1394
1395 int dest_i = to_i; // leave original alone for debug purposes
1396
1397 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1398 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1399
1400 switch (from_cp->tag_at(src_i).value()) {
1401 case JVM_CONSTANT_Double:
1402 case JVM_CONSTANT_Long:
1403 // double and long take two constant pool entries
1404 src_i += 2;
1405 dest_i += 2;
1406 break;
1407
1408 default:
1409 // all others take one constant pool entry
1410 src_i++;
1411 dest_i++;
1412 break;
1413 }
1414 }
1415 copy_operands(from_cp, to_cp, CHECK);
1416
1417 } // end copy_cp_to_impl()
1418
1419
1420 // Copy this constant pool's entry at from_i to the constant pool
1421 // to_cp's entry at to_i.
1422 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1423 const constantPoolHandle& to_cp, int to_i,
1424 TRAPS) {
1425
1426 int tag = from_cp->tag_at(from_i).value();
1427 switch (tag) {
1428 case JVM_CONSTANT_ClassIndex:
1429 {
1430 jint ki = from_cp->klass_index_at(from_i);
1431 to_cp->klass_index_at_put(to_i, ki);
1432 } break;
1433
1434 case JVM_CONSTANT_Double:
1435 {
1436 jdouble d = from_cp->double_at(from_i);
1437 to_cp->double_at_put(to_i, d);
1438 // double takes two constant pool entries so init second entry's tag
1439 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1440 } break;
1441
1442 case JVM_CONSTANT_Fieldref:
1443 {
1444 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1445 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1446 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1447 } break;
1448
1449 case JVM_CONSTANT_Float:
1450 {
1451 jfloat f = from_cp->float_at(from_i);
1452 to_cp->float_at_put(to_i, f);
1453 } break;
1454
1455 case JVM_CONSTANT_Integer:
1456 {
1457 jint i = from_cp->int_at(from_i);
1458 to_cp->int_at_put(to_i, i);
1459 } break;
1460
1461 case JVM_CONSTANT_InterfaceMethodref:
1462 {
1463 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1464 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1465 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1466 } break;
1467
1468 case JVM_CONSTANT_Long:
1469 {
1470 jlong l = from_cp->long_at(from_i);
1471 to_cp->long_at_put(to_i, l);
1472 // long takes two constant pool entries so init second entry's tag
1473 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1474 } break;
1475
1476 case JVM_CONSTANT_Methodref:
1477 {
1478 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1479 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1480 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1481 } break;
1482
1483 case JVM_CONSTANT_NameAndType:
1484 {
1485 int name_ref_index = from_cp->name_ref_index_at(from_i);
1486 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1487 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1488 } break;
1489
1490 case JVM_CONSTANT_StringIndex:
1491 {
1492 jint si = from_cp->string_index_at(from_i);
1493 to_cp->string_index_at_put(to_i, si);
1494 } break;
1495
1496 case JVM_CONSTANT_Class:
1497 case JVM_CONSTANT_UnresolvedClass:
1498 case JVM_CONSTANT_UnresolvedClassInError:
1499 {
1500 // Revert to JVM_CONSTANT_ClassIndex
1501 int name_index = from_cp->klass_slot_at(from_i).name_index();
1502 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1503 to_cp->klass_index_at_put(to_i, name_index);
1504 } break;
1505
1506 case JVM_CONSTANT_String:
1507 {
1508 Symbol* s = from_cp->unresolved_string_at(from_i);
1509 to_cp->unresolved_string_at_put(to_i, s);
1510 } break;
1511
1512 case JVM_CONSTANT_Utf8:
1513 {
1514 Symbol* s = from_cp->symbol_at(from_i);
1515 // Need to increase refcount, the old one will be thrown away and deferenced
1516 s->increment_refcount();
1517 to_cp->symbol_at_put(to_i, s);
1518 } break;
1519
1520 case JVM_CONSTANT_MethodType:
1521 case JVM_CONSTANT_MethodTypeInError:
1522 {
1523 jint k = from_cp->method_type_index_at(from_i);
1524 to_cp->method_type_index_at_put(to_i, k);
1525 } break;
1526
1527 case JVM_CONSTANT_MethodHandle:
1528 case JVM_CONSTANT_MethodHandleInError:
1529 {
1530 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1531 int k2 = from_cp->method_handle_index_at(from_i);
1532 to_cp->method_handle_index_at_put(to_i, k1, k2);
1533 } break;
1534
1535 case JVM_CONSTANT_InvokeDynamic:
1536 {
1537 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1538 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1539 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1540 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1541 } break;
1542
1543 // Invalid is used as the tag for the second constant pool entry
1544 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1545 // not be seen by itself.
1546 case JVM_CONSTANT_Invalid: // fall through
1547
1548 default:
1549 {
1550 ShouldNotReachHere();
1551 } break;
1552 }
1553 } // end copy_entry_to()
1554
1555 // Search constant pool search_cp for an entry that matches this
1556 // constant pool's entry at pattern_i. Returns the index of a
1557 // matching entry or zero (0) if there is no matching entry.
1558 int ConstantPool::find_matching_entry(int pattern_i,
1559 const constantPoolHandle& search_cp, TRAPS) {
1560
1561 // index zero (0) is not used
1562 for (int i = 1; i < search_cp->length(); i++) {
1563 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1564 if (found) {
1565 return i;
1566 }
1567 }
1568
1569 return 0; // entry not found; return unused index zero (0)
1570 } // end find_matching_entry()
1571
1572
1573 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1574 // cp2's bootstrap specifier at idx2.
1575 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1576 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1577 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1578 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1579
1580 if (!match) {
1581 return false;
1582 }
1583 int argc = operand_argument_count_at(idx1);
1584 if (argc == cp2->operand_argument_count_at(idx2)) {
1585 for (int j = 0; j < argc; j++) {
1586 k1 = operand_argument_index_at(idx1, j);
1587 k2 = cp2->operand_argument_index_at(idx2, j);
1588 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1589 if (!match) {
1590 return false;
1591 }
1592 }
1593 return true; // got through loop; all elements equal
1594 }
1595 return false;
1596 } // end compare_operand_to()
1597
1598 // Search constant pool search_cp for a bootstrap specifier that matches
1599 // this constant pool's bootstrap specifier at pattern_i index.
1600 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1601 int ConstantPool::find_matching_operand(int pattern_i,
1602 const constantPoolHandle& search_cp, int search_len, TRAPS) {
1603 for (int i = 0; i < search_len; i++) {
1604 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1605 if (found) {
1606 return i;
1607 }
1608 }
1609 return -1; // bootstrap specifier not found; return unused index (-1)
1610 } // end find_matching_operand()
1611
1612
1613 #ifndef PRODUCT
1614
1615 const char* ConstantPool::printable_name_at(int which) {
1616
1617 constantTag tag = tag_at(which);
1618
1619 if (tag.is_string()) {
1620 return string_at_noresolve(which);
1621 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1622 return klass_name_at(which)->as_C_string();
1623 } else if (tag.is_symbol()) {
1624 return symbol_at(which)->as_C_string();
1625 }
1626 return "";
1627 }
1628
1629 #endif // PRODUCT
1630
1631
1632 // JVMTI GetConstantPool support
1633
1634 // For debugging of constant pool
1635 const bool debug_cpool = false;
1636
1637 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1638
1639 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1640 const char* WARN_MSG = "Must not be such entry!";
1641 jint size = 0;
1642 u2 idx1, idx2;
1643
1644 for (jint idx = 1; idx < cnt; idx++) {
1645 jint ent_size = 0;
1646 u1 tag = *bytes++;
1647 size++; // count tag
1648
1649 printf("const #%03d, tag: %02d ", idx, tag);
1650 switch(tag) {
1651 case JVM_CONSTANT_Invalid: {
1652 printf("Invalid");
1653 break;
1654 }
1655 case JVM_CONSTANT_Unicode: {
1656 printf("Unicode %s", WARN_MSG);
1657 break;
1658 }
1659 case JVM_CONSTANT_Utf8: {
1660 u2 len = Bytes::get_Java_u2(bytes);
1661 char str[128];
1662 if (len > 127) {
1663 len = 127;
1664 }
1665 strncpy(str, (char *) (bytes+2), len);
1666 str[len] = '\0';
1667 printf("Utf8 \"%s\"", str);
1668 ent_size = 2 + len;
1669 break;
1670 }
1671 case JVM_CONSTANT_Integer: {
1672 u4 val = Bytes::get_Java_u4(bytes);
1673 printf("int %d", *(int *) &val);
1674 ent_size = 4;
1675 break;
1676 }
1677 case JVM_CONSTANT_Float: {
1678 u4 val = Bytes::get_Java_u4(bytes);
1679 printf("float %5.3ff", *(float *) &val);
1680 ent_size = 4;
1681 break;
1682 }
1683 case JVM_CONSTANT_Long: {
1684 u8 val = Bytes::get_Java_u8(bytes);
1685 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1686 ent_size = 8;
1687 idx++; // Long takes two cpool slots
1688 break;
1689 }
1690 case JVM_CONSTANT_Double: {
1691 u8 val = Bytes::get_Java_u8(bytes);
1692 printf("double %5.3fd", *(jdouble *)&val);
1693 ent_size = 8;
1694 idx++; // Double takes two cpool slots
1695 break;
1696 }
1697 case JVM_CONSTANT_Class: {
1698 idx1 = Bytes::get_Java_u2(bytes);
1699 printf("class #%03d", idx1);
1700 ent_size = 2;
1701 break;
1702 }
1703 case JVM_CONSTANT_String: {
1704 idx1 = Bytes::get_Java_u2(bytes);
1705 printf("String #%03d", idx1);
1706 ent_size = 2;
1707 break;
1708 }
1709 case JVM_CONSTANT_Fieldref: {
1710 idx1 = Bytes::get_Java_u2(bytes);
1711 idx2 = Bytes::get_Java_u2(bytes+2);
1712 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1713 ent_size = 4;
1714 break;
1715 }
1716 case JVM_CONSTANT_Methodref: {
1717 idx1 = Bytes::get_Java_u2(bytes);
1718 idx2 = Bytes::get_Java_u2(bytes+2);
1719 printf("Method #%03d, #%03d", idx1, idx2);
1720 ent_size = 4;
1721 break;
1722 }
1723 case JVM_CONSTANT_InterfaceMethodref: {
1724 idx1 = Bytes::get_Java_u2(bytes);
1725 idx2 = Bytes::get_Java_u2(bytes+2);
1726 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1727 ent_size = 4;
1728 break;
1729 }
1730 case JVM_CONSTANT_NameAndType: {
1731 idx1 = Bytes::get_Java_u2(bytes);
1732 idx2 = Bytes::get_Java_u2(bytes+2);
1733 printf("NameAndType #%03d, #%03d", idx1, idx2);
1734 ent_size = 4;
1735 break;
1736 }
1737 case JVM_CONSTANT_ClassIndex: {
1738 printf("ClassIndex %s", WARN_MSG);
1739 break;
1740 }
1741 case JVM_CONSTANT_UnresolvedClass: {
1742 printf("UnresolvedClass: %s", WARN_MSG);
1743 break;
1744 }
1745 case JVM_CONSTANT_UnresolvedClassInError: {
1746 printf("UnresolvedClassInErr: %s", WARN_MSG);
1747 break;
1748 }
1749 case JVM_CONSTANT_StringIndex: {
1750 printf("StringIndex: %s", WARN_MSG);
1751 break;
1752 }
1753 }
1754 printf(";\n");
1755 bytes += ent_size;
1756 size += ent_size;
1757 }
1758 printf("Cpool size: %d\n", size);
1759 fflush(0);
1760 return;
1761 } /* end print_cpool_bytes */
1762
1763
1764 // Returns size of constant pool entry.
1765 jint ConstantPool::cpool_entry_size(jint idx) {
1766 switch(tag_at(idx).value()) {
1767 case JVM_CONSTANT_Invalid:
1768 case JVM_CONSTANT_Unicode:
1769 return 1;
1770
1771 case JVM_CONSTANT_Utf8:
1772 return 3 + symbol_at(idx)->utf8_length();
1773
1774 case JVM_CONSTANT_Class:
1775 case JVM_CONSTANT_String:
1776 case JVM_CONSTANT_ClassIndex:
1777 case JVM_CONSTANT_UnresolvedClass:
1778 case JVM_CONSTANT_UnresolvedClassInError:
1779 case JVM_CONSTANT_StringIndex:
1780 case JVM_CONSTANT_MethodType:
1781 case JVM_CONSTANT_MethodTypeInError:
1782 return 3;
1783
1784 case JVM_CONSTANT_MethodHandle:
1785 case JVM_CONSTANT_MethodHandleInError:
1786 return 4; //tag, ref_kind, ref_index
1787
1788 case JVM_CONSTANT_Integer:
1789 case JVM_CONSTANT_Float:
1790 case JVM_CONSTANT_Fieldref:
1791 case JVM_CONSTANT_Methodref:
1792 case JVM_CONSTANT_InterfaceMethodref:
1793 case JVM_CONSTANT_NameAndType:
1794 return 5;
1795
1796 case JVM_CONSTANT_InvokeDynamic:
1797 // u1 tag, u2 bsm, u2 nt
1798 return 5;
1799
1800 case JVM_CONSTANT_Long:
1801 case JVM_CONSTANT_Double:
1802 return 9;
1803 }
1804 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1805 return 1;
1806 } /* end cpool_entry_size */
1807
1808
1809 // SymbolHashMap is used to find a constant pool index from a string.
1810 // This function fills in SymbolHashMaps, one for utf8s and one for
1811 // class names, returns size of the cpool raw bytes.
1812 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1813 SymbolHashMap *classmap) {
1814 jint size = 0;
1815
1816 for (u2 idx = 1; idx < length(); idx++) {
1817 u2 tag = tag_at(idx).value();
1818 size += cpool_entry_size(idx);
1819
1820 switch(tag) {
1821 case JVM_CONSTANT_Utf8: {
1822 Symbol* sym = symbol_at(idx);
1823 symmap->add_entry(sym, idx);
1824 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1825 break;
1826 }
1827 case JVM_CONSTANT_Class:
1828 case JVM_CONSTANT_UnresolvedClass:
1829 case JVM_CONSTANT_UnresolvedClassInError: {
1830 Symbol* sym = klass_name_at(idx);
1831 classmap->add_entry(sym, idx);
1832 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1833 break;
1834 }
1835 case JVM_CONSTANT_Long:
1836 case JVM_CONSTANT_Double: {
1837 idx++; // Both Long and Double take two cpool slots
1838 break;
1839 }
1840 }
1841 }
1842 return size;
1843 } /* end hash_utf8_entries_to */
1844
1845
1846 // Copy cpool bytes.
1847 // Returns:
1848 // 0, in case of OutOfMemoryError
1849 // -1, in case of internal error
1850 // > 0, count of the raw cpool bytes that have been copied
1851 int ConstantPool::copy_cpool_bytes(int cpool_size,
1852 SymbolHashMap* tbl,
1853 unsigned char *bytes) {
1854 u2 idx1, idx2;
1855 jint size = 0;
1856 jint cnt = length();
1857 unsigned char *start_bytes = bytes;
1858
1859 for (jint idx = 1; idx < cnt; idx++) {
1860 u1 tag = tag_at(idx).value();
1861 jint ent_size = cpool_entry_size(idx);
1862
1863 assert(size + ent_size <= cpool_size, "Size mismatch");
1864
1865 *bytes = tag;
1866 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
1867 switch(tag) {
1868 case JVM_CONSTANT_Invalid: {
1869 DBG(printf("JVM_CONSTANT_Invalid"));
1870 break;
1871 }
1872 case JVM_CONSTANT_Unicode: {
1873 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1874 DBG(printf("JVM_CONSTANT_Unicode"));
1875 break;
1876 }
1877 case JVM_CONSTANT_Utf8: {
1878 Symbol* sym = symbol_at(idx);
1879 char* str = sym->as_utf8();
1880 // Warning! It's crashing on x86 with len = sym->utf8_length()
1881 int len = (int) strlen(str);
1882 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1883 for (int i = 0; i < len; i++) {
1884 bytes[3+i] = (u1) str[i];
1885 }
1886 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1887 break;
1888 }
1889 case JVM_CONSTANT_Integer: {
1890 jint val = int_at(idx);
1891 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1892 break;
1893 }
1894 case JVM_CONSTANT_Float: {
1895 jfloat val = float_at(idx);
1896 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1897 break;
1898 }
1899 case JVM_CONSTANT_Long: {
1900 jlong val = long_at(idx);
1901 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1902 idx++; // Long takes two cpool slots
1903 break;
1904 }
1905 case JVM_CONSTANT_Double: {
1906 jdouble val = double_at(idx);
1907 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1908 idx++; // Double takes two cpool slots
1909 break;
1910 }
1911 case JVM_CONSTANT_Class:
1912 case JVM_CONSTANT_UnresolvedClass:
1913 case JVM_CONSTANT_UnresolvedClassInError: {
1914 *bytes = JVM_CONSTANT_Class;
1915 Symbol* sym = klass_name_at(idx);
1916 idx1 = tbl->symbol_to_value(sym);
1917 assert(idx1 != 0, "Have not found a hashtable entry");
1918 Bytes::put_Java_u2((address) (bytes+1), idx1);
1919 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1920 break;
1921 }
1922 case JVM_CONSTANT_String: {
1923 *bytes = JVM_CONSTANT_String;
1924 Symbol* sym = unresolved_string_at(idx);
1925 idx1 = tbl->symbol_to_value(sym);
1926 assert(idx1 != 0, "Have not found a hashtable entry");
1927 Bytes::put_Java_u2((address) (bytes+1), idx1);
1928 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1929 break;
1930 }
1931 case JVM_CONSTANT_Fieldref:
1932 case JVM_CONSTANT_Methodref:
1933 case JVM_CONSTANT_InterfaceMethodref: {
1934 idx1 = uncached_klass_ref_index_at(idx);
1935 idx2 = uncached_name_and_type_ref_index_at(idx);
1936 Bytes::put_Java_u2((address) (bytes+1), idx1);
1937 Bytes::put_Java_u2((address) (bytes+3), idx2);
1938 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1939 break;
1940 }
1941 case JVM_CONSTANT_NameAndType: {
1942 idx1 = name_ref_index_at(idx);
1943 idx2 = signature_ref_index_at(idx);
1944 Bytes::put_Java_u2((address) (bytes+1), idx1);
1945 Bytes::put_Java_u2((address) (bytes+3), idx2);
1946 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1947 break;
1948 }
1949 case JVM_CONSTANT_ClassIndex: {
1950 *bytes = JVM_CONSTANT_Class;
1951 idx1 = klass_index_at(idx);
1952 Bytes::put_Java_u2((address) (bytes+1), idx1);
1953 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1954 break;
1955 }
1956 case JVM_CONSTANT_StringIndex: {
1957 *bytes = JVM_CONSTANT_String;
1958 idx1 = string_index_at(idx);
1959 Bytes::put_Java_u2((address) (bytes+1), idx1);
1960 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1961 break;
1962 }
1963 case JVM_CONSTANT_MethodHandle:
1964 case JVM_CONSTANT_MethodHandleInError: {
1965 *bytes = JVM_CONSTANT_MethodHandle;
1966 int kind = method_handle_ref_kind_at(idx);
1967 idx1 = method_handle_index_at(idx);
1968 *(bytes+1) = (unsigned char) kind;
1969 Bytes::put_Java_u2((address) (bytes+2), idx1);
1970 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1971 break;
1972 }
1973 case JVM_CONSTANT_MethodType:
1974 case JVM_CONSTANT_MethodTypeInError: {
1975 *bytes = JVM_CONSTANT_MethodType;
1976 idx1 = method_type_index_at(idx);
1977 Bytes::put_Java_u2((address) (bytes+1), idx1);
1978 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1979 break;
1980 }
1981 case JVM_CONSTANT_InvokeDynamic: {
1982 *bytes = tag;
1983 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1984 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1985 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1986 Bytes::put_Java_u2((address) (bytes+1), idx1);
1987 Bytes::put_Java_u2((address) (bytes+3), idx2);
1988 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1989 break;
1990 }
1991 }
1992 DBG(printf("\n"));
1993 bytes += ent_size;
1994 size += ent_size;
1995 }
1996 assert(size == cpool_size, "Size mismatch");
1997
1998 // Keep temorarily for debugging until it's stable.
1999 DBG(print_cpool_bytes(cnt, start_bytes));
2000 return (int)(bytes - start_bytes);
2001 } /* end copy_cpool_bytes */
2002
2003 #undef DBG
2004
2005
2006 void ConstantPool::set_on_stack(const bool value) {
2007 if (value) {
2008 // Only record if it's not already set.
2009 if (!on_stack()) {
2010 assert(!is_shared(), "should always be set for shared constant pools");
2011 _flags |= _on_stack;
2012 MetadataOnStackMark::record(this);
2013 }
2014 } else {
2015 // Clearing is done single-threadedly.
2016 if (!is_shared()) {
2017 _flags &= ~_on_stack;
2018 }
2019 }
2020 }
2021
2022 // JSR 292 support for patching constant pool oops after the class is linked and
2023 // the oop array for resolved references are created.
2024 // We can't do this during classfile parsing, which is how the other indexes are
2025 // patched. The other patches are applied early for some error checking
2026 // so only defer the pseudo_strings.
2027 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
2028 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
2029 Handle patch = cp_patches->at(index);
2030 if (patch.not_null()) {
2031 assert (tag_at(index).is_string(), "should only be string left");
2032 // Patching a string means pre-resolving it.
2033 // The spelling in the constant pool is ignored.
2034 // The constant reference may be any object whatever.
2035 // If it is not a real interned string, the constant is referred
2036 // to as a "pseudo-string", and must be presented to the CP
2037 // explicitly, because it may require scavenging.
2038 int obj_index = cp_to_object_index(index);
2039 pseudo_string_at_put(index, obj_index, patch());
2040 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
2041 }
2042 }
2043 #ifdef ASSERT
2044 // Ensure that all the patches have been used.
2045 for (int index = 0; index < cp_patches->length(); index++) {
2046 assert(cp_patches->at(index).is_null(),
2047 "Unused constant pool patch at %d in class file %s",
2048 index,
2049 pool_holder()->external_name());
2050 }
2051 #endif // ASSERT
2052 }
2053
2054 #ifndef PRODUCT
2055
2056 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
2057 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
2058 guarantee(obj->is_constantPool(), "object must be constant pool");
2059 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
2060 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
2061
2062 for (int i = 0; i< cp->length(); i++) {
2063 if (cp->tag_at(i).is_unresolved_klass()) {
2064 // This will force loading of the class
2065 Klass* klass = cp->klass_at(i, CHECK);
2066 if (klass->is_instance_klass()) {
2067 // Force initialization of class
2068 InstanceKlass::cast(klass)->initialize(CHECK);
2069 }
2070 }
2071 }
2072 }
2073
2074 #endif
2075
2076
2077 // Printing
2078
2079 void ConstantPool::print_on(outputStream* st) const {
2080 assert(is_constantPool(), "must be constantPool");
2081 st->print_cr("%s", internal_name());
2082 if (flags() != 0) {
2083 st->print(" - flags: 0x%x", flags());
2084 if (has_preresolution()) st->print(" has_preresolution");
2085 if (on_stack()) st->print(" on_stack");
2086 st->cr();
2087 }
2088 if (pool_holder() != NULL) {
2089 st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
2090 }
2091 st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
2092 st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
2093 st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
2094 st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
2095
2096 for (int index = 1; index < length(); index++) { // Index 0 is unused
2097 ((ConstantPool*)this)->print_entry_on(index, st);
2098 switch (tag_at(index).value()) {
2099 case JVM_CONSTANT_Long :
2100 case JVM_CONSTANT_Double :
2101 index++; // Skip entry following eigth-byte constant
2102 }
2103
2104 }
2105 st->cr();
2106 }
2107
2108 // Print one constant pool entry
2109 void ConstantPool::print_entry_on(const int index, outputStream* st) {
2110 EXCEPTION_MARK;
2111 st->print(" - %3d : ", index);
2112 tag_at(index).print_on(st);
2113 st->print(" : ");
2114 switch (tag_at(index).value()) {
2115 case JVM_CONSTANT_Class :
2116 { Klass* k = klass_at(index, CATCH);
2117 guarantee(k != NULL, "need klass");
2118 k->print_value_on(st);
2119 st->print(" {" PTR_FORMAT "}", p2i(k));
2120 }
2121 break;
2122 case JVM_CONSTANT_Fieldref :
2123 case JVM_CONSTANT_Methodref :
2124 case JVM_CONSTANT_InterfaceMethodref :
2125 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
2126 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
2127 break;
2128 case JVM_CONSTANT_String :
2129 if (is_pseudo_string_at(index)) {
2130 oop anObj = pseudo_string_at(index);
2131 anObj->print_value_on(st);
2132 st->print(" {" PTR_FORMAT "}", p2i(anObj));
2133 } else {
2134 unresolved_string_at(index)->print_value_on(st);
2135 }
2136 break;
2137 case JVM_CONSTANT_Integer :
2138 st->print("%d", int_at(index));
2139 break;
2140 case JVM_CONSTANT_Float :
2141 st->print("%f", float_at(index));
2142 break;
2143 case JVM_CONSTANT_Long :
2144 st->print_jlong(long_at(index));
2145 break;
2146 case JVM_CONSTANT_Double :
2147 st->print("%lf", double_at(index));
2148 break;
2149 case JVM_CONSTANT_NameAndType :
2150 st->print("name_index=%d", name_ref_index_at(index));
2151 st->print(" signature_index=%d", signature_ref_index_at(index));
2152 break;
2153 case JVM_CONSTANT_Utf8 :
2154 symbol_at(index)->print_value_on(st);
2155 break;
2156 case JVM_CONSTANT_ClassIndex: {
2157 int name_index = *int_at_addr(index);
2158 st->print("klass_index=%d ", name_index);
2159 symbol_at(name_index)->print_value_on(st);
2160 }
2161 break;
2162 case JVM_CONSTANT_UnresolvedClass : // fall-through
2163 case JVM_CONSTANT_UnresolvedClassInError: {
2164 CPKlassSlot kslot = klass_slot_at(index);
2165 int resolved_klass_index = kslot.resolved_klass_index();
2166 int name_index = kslot.name_index();
2167 assert(tag_at(name_index).is_symbol(), "sanity");
2168
2169 Klass* klass = resolved_klasses()->at(resolved_klass_index);
2170 if (klass != NULL) {
2171 klass->print_value_on(st);
2172 } else {
2173 symbol_at(name_index)->print_value_on(st);
2174 }
2175 }
2176 break;
2177 case JVM_CONSTANT_MethodHandle :
2178 case JVM_CONSTANT_MethodHandleInError :
2179 st->print("ref_kind=%d", method_handle_ref_kind_at(index));
2180 st->print(" ref_index=%d", method_handle_index_at(index));
2181 break;
2182 case JVM_CONSTANT_MethodType :
2183 case JVM_CONSTANT_MethodTypeInError :
2184 st->print("signature_index=%d", method_type_index_at(index));
2185 break;
2186 case JVM_CONSTANT_InvokeDynamic :
2187 {
2188 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2189 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2190 int argc = invoke_dynamic_argument_count_at(index);
2191 if (argc > 0) {
2192 for (int arg_i = 0; arg_i < argc; arg_i++) {
2193 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2194 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2195 }
2196 st->print("}");
2197 }
2198 }
2199 break;
2200 default:
2201 ShouldNotReachHere();
2202 break;
2203 }
2204 st->cr();
2205 }
2206
2207 void ConstantPool::print_value_on(outputStream* st) const {
2208 assert(is_constantPool(), "must be constantPool");
2209 st->print("constant pool [%d]", length());
2210 if (has_preresolution()) st->print("/preresolution");
2211 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2212 print_address_on(st);
2213 st->print(" for ");
2214 pool_holder()->print_value_on(st);
2215 if (pool_holder() != NULL) {
2216 bool extra = (pool_holder()->constants() != this);
2217 if (extra) st->print(" (extra)");
2218 }
2219 if (cache() != NULL) {
2220 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2221 }
2222 }
2223
2224 #if INCLUDE_SERVICES
2225 // Size Statistics
2226 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2227 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2228 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2229 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2230 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2231 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2232
2233 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2234 sz->_cp_refmap_bytes;
2235 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2236 }
2237 #endif // INCLUDE_SERVICES
2238
2239 // Verification
2240
2241 void ConstantPool::verify_on(outputStream* st) {
2242 guarantee(is_constantPool(), "object must be constant pool");
2243 for (int i = 0; i< length(); i++) {
2244 constantTag tag = tag_at(i);
2245 if (tag.is_klass() || tag.is_unresolved_klass()) {
2246 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2247 } else if (tag.is_symbol()) {
2248 CPSlot entry = slot_at(i);
2249 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2250 } else if (tag.is_string()) {
2251 CPSlot entry = slot_at(i);
2252 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2253 }
2254 }
2255 if (cache() != NULL) {
2256 // Note: cache() can be NULL before a class is completely setup or
2257 // in temporary constant pools used during constant pool merging
2258 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2259 }
2260 if (pool_holder() != NULL) {
2261 // Note: pool_holder() can be NULL in temporary constant pools
2262 // used during constant pool merging
2263 guarantee(pool_holder()->is_klass(), "should be klass");
2264 }
2265 }
2266
2267
2268 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2269 char *str = sym->as_utf8();
2270 unsigned int hash = compute_hash(str, sym->utf8_length());
2271 unsigned int index = hash % table_size();
2272
2273 // check if already in map
2274 // we prefer the first entry since it is more likely to be what was used in
2275 // the class file
2276 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2277 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2278 if (en->hash() == hash && en->symbol() == sym) {
2279 return; // already there
2280 }
2281 }
2282
2283 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2284 entry->set_next(bucket(index));
2285 _buckets[index].set_entry(entry);
2286 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2287 }
2288
2289 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2290 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2291 char *str = sym->as_utf8();
2292 int len = sym->utf8_length();
2293 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2294 unsigned int index = hash % table_size();
2295 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2296 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2297 if (en->hash() == hash && en->symbol() == sym) {
2298 return en;
2299 }
2300 }
2301 return NULL;
2302 }