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 // 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_ptr((Klass* volatile *)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_ptr((Klass* volatile *)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()) {
309 Symbol* sym = cp->unresolved_string_at(index);
310 // Look up only. Only resolve references to already interned strings.
311 oop str = StringTable::lookup(sym);
312 if (str != NULL) {
313 int cache_index = cp->cp_to_object_index(index);
314 cp->string_at_put(index, cache_index, str);
315 }
316 }
317 }
318 }
319 #endif
320
321 // CDS support. Create a new resolved_references array.
322 void ConstantPool::restore_unshareable_info(TRAPS) {
323 assert(is_constantPool(), "ensure C++ vtable is restored");
324 assert(on_stack(), "should always be set for shared constant pools");
325 assert(is_shared(), "should always be set for shared constant pools");
326 assert(_cache != NULL, "constant pool _cache should not be NULL");
327
328 // Only create the new resolved references array if it hasn't been attempted before
329 if (resolved_references() != NULL) return;
330
331 // restore the C++ vtable from the shared archive
332 restore_vtable();
333
334 if (SystemDictionary::Object_klass_loaded()) {
335 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
336 #if INCLUDE_CDS_JAVA_HEAP
337 if (MetaspaceShared::open_archive_heap_region_mapped() &&
338 _cache->archived_references() != NULL) {
339 oop archived = _cache->archived_references();
340 // Make sure GC knows the cached object is now live. This is necessary after
341 // initial GC marking and during concurrent marking as strong roots are only
342 // scanned during initial marking (at the start of the GC marking).
343 assert(UseG1GC, "Requires G1 GC");
344 G1SATBCardTableModRefBS::enqueue(archived);
345 // Create handle for the archived resolved reference array object
346 Handle refs_handle(THREAD, (oop)archived);
347 set_resolved_references(loader_data->add_handle(refs_handle));
348 } else
349 #endif
350 {
351 // No mapped archived resolved reference array
352 // Recreate the object array and add to ClassLoaderData.
353 int map_length = resolved_reference_length();
354 if (map_length > 0) {
355 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
356 Handle refs_handle(THREAD, (oop)stom); // must handleize.
357 set_resolved_references(loader_data->add_handle(refs_handle));
358 }
359 }
360 }
361 }
362
363 void ConstantPool::remove_unshareable_info() {
364 // Resolved references are not in the shared archive.
365 // Save the length for restoration. It is not necessarily the same length
366 // as reference_map.length() if invokedynamic is saved. It is needed when
367 // re-creating the resolved reference array if archived heap data cannot be map
368 // at runtime.
369 set_resolved_reference_length(
370 resolved_references() != NULL ? resolved_references()->length() : 0);
371
372 // If archiving heap objects is not allowed, clear the resolved references.
373 // Otherwise, it is cleared after the resolved references array is cached
374 // (see archive_resolved_references()).
375 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
376 set_resolved_references(NULL);
377 }
378
379 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
380 // The _on_stack flag is used to prevent ConstantPools from deallocation during
381 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
382 // we always set _on_stack to true to avoid having to change _flags during runtime.
383 _flags |= (_on_stack | _is_shared);
384 int num_klasses = 0;
385 for (int index = 1; index < length(); index++) { // Index 0 is unused
386 assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
387 if (tag_at(index).is_klass()) {
388 // This class was resolved as a side effect of executing Java code
389 // during dump time. We need to restore it back to an UnresolvedClass,
390 // so that the proper class loading and initialization can happen
391 // at runtime.
392 CPKlassSlot kslot = klass_slot_at(index);
393 int resolved_klass_index = kslot.resolved_klass_index();
394 int name_index = kslot.name_index();
395 assert(tag_at(name_index).is_symbol(), "sanity");
396 resolved_klasses()->at_put(resolved_klass_index, NULL);
397 tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
398 assert(klass_name_at(index) == symbol_at(name_index), "sanity");
399 }
400 }
401 if (cache() != NULL) {
402 cache()->remove_unshareable_info();
403 }
404 }
405
406 int ConstantPool::cp_to_object_index(int cp_index) {
407 // this is harder don't do this so much.
408 int i = reference_map()->find(cp_index);
409 // We might not find the index for jsr292 call.
410 return (i < 0) ? _no_index_sentinel : i;
411 }
412
413 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
414 resolved_references()->obj_at_put(obj_index, str);
415 }
416
417 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
418 ResourceMark rm;
419 int line_number = -1;
420 const char * source_file = NULL;
421 if (JavaThread::current()->has_last_Java_frame()) {
422 // try to identify the method which called this function.
423 vframeStream vfst(JavaThread::current());
424 if (!vfst.at_end()) {
425 line_number = vfst.method()->line_number_from_bci(vfst.bci());
426 Symbol* s = vfst.method()->method_holder()->source_file_name();
427 if (s != NULL) {
428 source_file = s->as_C_string();
429 }
430 }
431 }
432 if (k != this_cp->pool_holder()) {
433 // only print something if the classes are different
434 if (source_file != NULL) {
435 log_debug(class, resolve)("%s %s %s:%d",
436 this_cp->pool_holder()->external_name(),
437 k->external_name(), source_file, line_number);
438 } else {
439 log_debug(class, resolve)("%s %s",
440 this_cp->pool_holder()->external_name(),
441 k->external_name());
442 }
443 }
444 }
445
446 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
447 bool save_resolution_error, TRAPS) {
448 assert(THREAD->is_Java_thread(), "must be a Java thread");
449
450 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
451 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
452 // the entry and tag is not updated atomicly.
453 CPKlassSlot kslot = this_cp->klass_slot_at(which);
454 int resolved_klass_index = kslot.resolved_klass_index();
455 int name_index = kslot.name_index();
456 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
457
458 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
459 if (klass != NULL) {
460 return klass;
461 }
462
463 // This tag doesn't change back to unresolved class unless at a safepoint.
464 if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
465 // The original attempt to resolve this constant pool entry failed so find the
466 // class of the original error and throw another error of the same class
467 // (JVMS 5.4.3).
468 // If there is a detail message, pass that detail message to the error.
469 // The JVMS does not strictly require us to duplicate the same detail message,
470 // or any internal exception fields such as cause or stacktrace. But since the
471 // detail message is often a class name or other literal string, we will repeat it
472 // if we can find it in the symbol table.
473 throw_resolution_error(this_cp, which, CHECK_0);
474 ShouldNotReachHere();
475 }
476
477 Handle mirror_handle;
478 Symbol* name = this_cp->symbol_at(name_index);
479 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
480 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
481 Klass* k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
482 if (!HAS_PENDING_EXCEPTION) {
483 // preserve the resolved klass from unloading
484 mirror_handle = Handle(THREAD, k->java_mirror());
485 // Do access check for klasses
486 verify_constant_pool_resolve(this_cp, k, THREAD);
487 }
488
489 // Failed to resolve class. We must record the errors so that subsequent attempts
490 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
491 if (HAS_PENDING_EXCEPTION) {
492 if (save_resolution_error) {
493 save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
494 // If CHECK_NULL above doesn't return the exception, that means that
495 // some other thread has beaten us and has resolved the class.
496 // To preserve old behavior, we return the resolved class.
497 klass = this_cp->resolved_klasses()->at(resolved_klass_index);
498 assert(klass != NULL, "must be resolved if exception was cleared");
499 return klass;
500 } else {
501 return NULL; // return the pending exception
502 }
503 }
504
505 // Make this class loader depend upon the class loader owning the class reference
506 ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
507 this_key->record_dependency(k, CHECK_NULL); // Can throw OOM
508
509 // logging for class+resolve.
510 if (log_is_enabled(Debug, class, resolve)){
511 trace_class_resolution(this_cp, k);
512 }
513 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
514 OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
515 // The interpreter assumes when the tag is stored, the klass is resolved
516 // and the Klass* stored in _resolved_klasses is non-NULL, so we need
517 // hardware store ordering here.
518 this_cp->release_tag_at_put(which, JVM_CONSTANT_Class);
519 return k;
520 }
521
522
523 // Does not update ConstantPool* - to avoid any exception throwing. Used
524 // by compiler and exception handling. Also used to avoid classloads for
525 // instanceof operations. Returns NULL if the class has not been loaded or
526 // if the verification of constant pool failed
527 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
528 CPKlassSlot kslot = this_cp->klass_slot_at(which);
529 int resolved_klass_index = kslot.resolved_klass_index();
530 int name_index = kslot.name_index();
531 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
532
533 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
534 if (k != NULL) {
535 return k;
536 } else {
537 Thread *thread = Thread::current();
538 Symbol* name = this_cp->symbol_at(name_index);
539 oop loader = this_cp->pool_holder()->class_loader();
540 oop protection_domain = this_cp->pool_holder()->protection_domain();
541 Handle h_prot (thread, protection_domain);
542 Handle h_loader (thread, loader);
543 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
544
545 if (k != NULL) {
546 // Make sure that resolving is legal
547 EXCEPTION_MARK;
548 // return NULL if verification fails
549 verify_constant_pool_resolve(this_cp, k, THREAD);
550 if (HAS_PENDING_EXCEPTION) {
551 CLEAR_PENDING_EXCEPTION;
552 return NULL;
553 }
554 return k;
555 } else {
556 return k;
557 }
558 }
559 }
560
561
562 Klass* ConstantPool::klass_ref_at_if_loaded(const constantPoolHandle& this_cp, int which) {
563 return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
564 }
565
566
567 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
568 int which) {
569 if (cpool->cache() == NULL) return NULL; // nothing to load yet
570 int cache_index = decode_cpcache_index(which, true);
571 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
572 // FIXME: should be an assert
573 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
574 return NULL;
575 }
576 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
577 return e->method_if_resolved(cpool);
578 }
579
580
581 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
582 if (cpool->cache() == NULL) return false; // nothing to load yet
583 int cache_index = decode_cpcache_index(which, true);
584 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
585 return e->has_appendix();
586 }
587
588 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
589 if (cpool->cache() == NULL) return NULL; // nothing to load yet
590 int cache_index = decode_cpcache_index(which, true);
591 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
592 return e->appendix_if_resolved(cpool);
593 }
594
595
596 bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
597 if (cpool->cache() == NULL) return false; // nothing to load yet
598 int cache_index = decode_cpcache_index(which, true);
599 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
600 return e->has_method_type();
601 }
602
603 oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
604 if (cpool->cache() == NULL) return NULL; // nothing to load yet
605 int cache_index = decode_cpcache_index(which, true);
606 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
607 return e->method_type_if_resolved(cpool);
608 }
609
610
611 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
612 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
613 return symbol_at(name_index);
614 }
615
616
617 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
618 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
619 return symbol_at(signature_index);
620 }
621
622
623 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
624 int i = which;
625 if (!uncached && cache() != NULL) {
626 if (ConstantPool::is_invokedynamic_index(which)) {
627 // Invokedynamic index is index into the constant pool cache
628 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
629 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
630 assert(tag_at(pool_index).is_name_and_type(), "");
631 return pool_index;
632 }
633 // change byte-ordering and go via cache
634 i = remap_instruction_operand_from_cache(which);
635 } else {
636 if (tag_at(which).is_invoke_dynamic()) {
637 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
638 assert(tag_at(pool_index).is_name_and_type(), "");
639 return pool_index;
640 }
641 }
642 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
643 assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
644 jint ref_index = *int_at_addr(i);
645 return extract_high_short_from_int(ref_index);
646 }
647
648 constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
649 int pool_index = which;
650 if (!uncached && cache() != NULL) {
651 if (ConstantPool::is_invokedynamic_index(which)) {
652 // Invokedynamic index is index into resolved_references
653 pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
654 } else {
655 // change byte-ordering and go via cache
656 pool_index = remap_instruction_operand_from_cache(which);
657 }
658 }
659 return tag_at(pool_index);
660 }
661
662 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
663 guarantee(!ConstantPool::is_invokedynamic_index(which),
664 "an invokedynamic instruction does not have a klass");
665 int i = which;
666 if (!uncached && cache() != NULL) {
667 // change byte-ordering and go via cache
668 i = remap_instruction_operand_from_cache(which);
669 }
670 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
671 jint ref_index = *int_at_addr(i);
672 return extract_low_short_from_int(ref_index);
673 }
674
675
676
677 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
678 int cpc_index = operand;
679 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
680 assert((int)(u2)cpc_index == cpc_index, "clean u2");
681 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
682 return member_index;
683 }
684
685
686 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
687 if (k->is_instance_klass() || k->is_objArray_klass()) {
688 InstanceKlass* holder = this_cp->pool_holder();
689 Klass* elem = k->is_instance_klass() ? k : ObjArrayKlass::cast(k)->bottom_klass();
690
691 // The element type could be a typeArray - we only need the access check if it is
692 // an reference to another class
693 if (elem->is_instance_klass()) {
694 LinkResolver::check_klass_accessability(holder, elem, CHECK);
695 }
696 }
697 }
698
699
700 int ConstantPool::name_ref_index_at(int which_nt) {
701 jint ref_index = name_and_type_at(which_nt);
702 return extract_low_short_from_int(ref_index);
703 }
704
705
706 int ConstantPool::signature_ref_index_at(int which_nt) {
707 jint ref_index = name_and_type_at(which_nt);
708 return extract_high_short_from_int(ref_index);
709 }
710
711
712 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
713 return klass_at(klass_ref_index_at(which), THREAD);
714 }
715
716 Symbol* ConstantPool::klass_name_at(int which) const {
717 return symbol_at(klass_slot_at(which).name_index());
718 }
719
720 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
721 jint ref_index = klass_ref_index_at(which);
722 return klass_at_noresolve(ref_index);
723 }
724
725 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
726 jint ref_index = uncached_klass_ref_index_at(which);
727 return klass_at_noresolve(ref_index);
728 }
729
730 char* ConstantPool::string_at_noresolve(int which) {
731 return unresolved_string_at(which)->as_C_string();
732 }
733
734 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
735 return FieldType::basic_type(symbol_at(which));
736 }
737
738
739 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
740 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
741 if (this_cp->tag_at(index).is_string()) {
742 this_cp->string_at(index, CHECK);
743 }
744 }
745 }
746
747 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
748 // Dig out the detailed message to reuse if possible
749 Symbol* message = java_lang_Throwable::detail_message(pending_exception);
750 if (message != NULL) {
751 return message;
752 }
753
754 // Return specific message for the tag
755 switch (tag.value()) {
756 case JVM_CONSTANT_UnresolvedClass:
757 // return the class name in the error message
758 message = this_cp->klass_name_at(which);
759 break;
760 case JVM_CONSTANT_MethodHandle:
761 // return the method handle name in the error message
762 message = this_cp->method_handle_name_ref_at(which);
763 break;
764 case JVM_CONSTANT_MethodType:
765 // return the method type signature in the error message
766 message = this_cp->method_type_signature_at(which);
767 break;
768 default:
769 ShouldNotReachHere();
770 }
771
772 return message;
773 }
774
775 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
776 Symbol* message = NULL;
777 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
778 assert(error != NULL && message != NULL, "checking");
779 CLEAR_PENDING_EXCEPTION;
780 ResourceMark rm;
781 THROW_MSG(error, message->as_C_string());
782 }
783
784 // If resolution for Class, MethodHandle or MethodType fails, save the exception
785 // in the resolution error table, so that the same exception is thrown again.
786 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
787 constantTag tag, TRAPS) {
788 Symbol* error = PENDING_EXCEPTION->klass()->name();
789
790 int error_tag = tag.error_value();
791
792 if (!PENDING_EXCEPTION->
793 is_a(SystemDictionary::LinkageError_klass())) {
794 // Just throw the exception and don't prevent these classes from
795 // being loaded due to virtual machine errors like StackOverflow
796 // and OutOfMemoryError, etc, or if the thread was hit by stop()
797 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
798 } else if (this_cp->tag_at(which).value() != error_tag) {
799 Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
800 SystemDictionary::add_resolution_error(this_cp, which, error, message);
801 // CAS in the tag. If a thread beat us to registering this error that's fine.
802 // If another thread resolved the reference, this is a race condition. This
803 // thread may have had a security manager or something temporary.
804 // This doesn't deterministically get an error. So why do we save this?
805 // We save this because jvmti can add classes to the bootclass path after
806 // this error, so it needs to get the same error if the error is first.
807 jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
808 (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
809 if (old_tag != error_tag && old_tag != tag.value()) {
810 // MethodHandles and MethodType doesn't change to resolved version.
811 assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
812 // Forget the exception and use the resolved class.
813 CLEAR_PENDING_EXCEPTION;
814 }
815 } else {
816 // some other thread put this in error state
817 throw_resolution_error(this_cp, which, CHECK);
818 }
819 }
820
821 // Called to resolve constants in the constant pool and return an oop.
822 // Some constant pool entries cache their resolved oop. This is also
823 // called to create oops from constants to use in arguments for invokedynamic
824 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS) {
825 oop result_oop = NULL;
826 Handle throw_exception;
827
828 if (cache_index == _possible_index_sentinel) {
829 // It is possible that this constant is one which is cached in the objects.
830 // We'll do a linear search. This should be OK because this usage is rare.
831 assert(index > 0, "valid index");
832 cache_index = this_cp->cp_to_object_index(index);
833 }
834 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
835 assert(index == _no_index_sentinel || index >= 0, "");
836
837 if (cache_index >= 0) {
838 result_oop = this_cp->resolved_references()->obj_at(cache_index);
839 if (result_oop != NULL) {
840 return result_oop;
841 // That was easy...
842 }
843 index = this_cp->object_to_cp_index(cache_index);
844 }
845
846 jvalue prim_value; // temp used only in a few cases below
847
848 constantTag tag = this_cp->tag_at(index);
849
850 switch (tag.value()) {
851
852 case JVM_CONSTANT_UnresolvedClass:
853 case JVM_CONSTANT_UnresolvedClassInError:
854 case JVM_CONSTANT_Class:
855 {
856 assert(cache_index == _no_index_sentinel, "should not have been set");
857 Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
858 // ldc wants the java mirror.
859 result_oop = resolved->java_mirror();
860 break;
861 }
862
863 case JVM_CONSTANT_String:
864 assert(cache_index != _no_index_sentinel, "should have been set");
865 if (this_cp->is_pseudo_string_at(index)) {
866 result_oop = this_cp->pseudo_string_at(index, cache_index);
867 break;
868 }
869 result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
870 break;
871
872 case JVM_CONSTANT_MethodHandleInError:
873 case JVM_CONSTANT_MethodTypeInError:
874 {
875 throw_resolution_error(this_cp, index, CHECK_NULL);
876 break;
877 }
878
879 case JVM_CONSTANT_MethodHandle:
880 {
881 int ref_kind = this_cp->method_handle_ref_kind_at(index);
882 int callee_index = this_cp->method_handle_klass_index_at(index);
883 Symbol* name = this_cp->method_handle_name_ref_at(index);
884 Symbol* signature = this_cp->method_handle_signature_ref_at(index);
885 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(index));
886 { ResourceMark rm(THREAD);
887 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
888 ref_kind, index, this_cp->method_handle_index_at(index),
889 callee_index, name->as_C_string(), signature->as_C_string());
890 }
891
892 Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
893
894 // Check constant pool method consistency
895 if ((callee->is_interface() && m_tag.is_method()) ||
896 ((!callee->is_interface() && m_tag.is_interface_method()))) {
897 ResourceMark rm(THREAD);
898 char buf[400];
899 jio_snprintf(buf, sizeof(buf),
900 "Inconsistent constant pool data in classfile for class %s. "
901 "Method %s%s at index %d is %s and should be %s",
902 callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
903 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
904 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
905 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
906 }
907
908 Klass* klass = this_cp->pool_holder();
909 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
910 callee, name, signature,
911 THREAD);
912 result_oop = value();
913 if (HAS_PENDING_EXCEPTION) {
914 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
915 }
916 break;
917 }
918
919 case JVM_CONSTANT_MethodType:
920 {
921 Symbol* signature = this_cp->method_type_signature_at(index);
922 { ResourceMark rm(THREAD);
923 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
924 index, this_cp->method_type_index_at(index),
925 signature->as_C_string());
926 }
927 Klass* klass = this_cp->pool_holder();
928 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
929 result_oop = value();
930 if (HAS_PENDING_EXCEPTION) {
931 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
932 }
933 break;
934 }
935
936 case JVM_CONSTANT_Integer:
937 assert(cache_index == _no_index_sentinel, "should not have been set");
938 prim_value.i = this_cp->int_at(index);
939 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
940 break;
941
942 case JVM_CONSTANT_Float:
943 assert(cache_index == _no_index_sentinel, "should not have been set");
944 prim_value.f = this_cp->float_at(index);
945 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
946 break;
947
948 case JVM_CONSTANT_Long:
949 assert(cache_index == _no_index_sentinel, "should not have been set");
950 prim_value.j = this_cp->long_at(index);
951 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
952 break;
953
954 case JVM_CONSTANT_Double:
955 assert(cache_index == _no_index_sentinel, "should not have been set");
956 prim_value.d = this_cp->double_at(index);
957 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
958 break;
959
960 default:
961 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
962 this_cp(), index, cache_index, tag.value()));
963 assert(false, "unexpected constant tag");
964 break;
965 }
966
967 if (cache_index >= 0) {
968 // Benign race condition: resolved_references may already be filled in.
969 // The important thing here is that all threads pick up the same result.
970 // It doesn't matter which racing thread wins, as long as only one
971 // result is used by all threads, and all future queries.
972 oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
973 if (old_result == NULL) {
974 return result_oop; // was installed
975 } else {
976 // Return the winning thread's result. This can be different than
977 // the result here for MethodHandles.
978 return old_result;
979 }
980 } else {
981 return result_oop;
982 }
983 }
984
985 oop ConstantPool::uncached_string_at(int which, TRAPS) {
986 Symbol* sym = unresolved_string_at(which);
987 oop str = StringTable::intern(sym, CHECK_(NULL));
988 assert(java_lang_String::is_instance(str), "must be string");
989 return str;
990 }
991
992
993 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
994 assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
995
996 Handle bsm;
997 int argc;
998 {
999 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
1000 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
1001 // It is accompanied by the optional arguments.
1002 int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
1003 oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
1004 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
1005 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
1006 }
1007
1008 // Extract the optional static arguments.
1009 argc = this_cp->invoke_dynamic_argument_count_at(index);
1010 if (argc == 0) return bsm_oop;
1011
1012 bsm = Handle(THREAD, bsm_oop);
1013 }
1014
1015 objArrayHandle info;
1016 {
1017 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
1018 info = objArrayHandle(THREAD, info_oop);
1019 }
1020
1021 info->obj_at_put(0, bsm());
1022 for (int i = 0; i < argc; i++) {
1023 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1024 oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
1025 info->obj_at_put(1+i, arg_oop);
1026 }
1027
1028 return info();
1029 }
1030
1031 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
1032 // If the string has already been interned, this entry will be non-null
1033 oop str = this_cp->resolved_references()->obj_at(obj_index);
1034 if (str != NULL) return str;
1035 Symbol* sym = this_cp->unresolved_string_at(which);
1036 str = StringTable::intern(sym, CHECK_(NULL));
1037 this_cp->string_at_put(which, obj_index, str);
1038 assert(java_lang_String::is_instance(str), "must be string");
1039 return str;
1040 }
1041
1042
1043 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
1044 // Names are interned, so we can compare Symbol*s directly
1045 Symbol* cp_name = klass_name_at(which);
1046 return (cp_name == k->name());
1047 }
1048
1049
1050 // Iterate over symbols and decrement ones which are Symbol*s
1051 // This is done during GC.
1052 // Only decrement the UTF8 symbols. Strings point to
1053 // these symbols but didn't increment the reference count.
1054 void ConstantPool::unreference_symbols() {
1055 for (int index = 1; index < length(); index++) { // Index 0 is unused
1056 constantTag tag = tag_at(index);
1057 if (tag.is_symbol()) {
1058 symbol_at(index)->decrement_refcount();
1059 }
1060 }
1061 }
1062
1063
1064 // Compare this constant pool's entry at index1 to the constant pool
1065 // cp2's entry at index2.
1066 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1067 int index2, TRAPS) {
1068
1069 // The error tags are equivalent to non-error tags when comparing
1070 jbyte t1 = tag_at(index1).non_error_value();
1071 jbyte t2 = cp2->tag_at(index2).non_error_value();
1072
1073 if (t1 != t2) {
1074 // Not the same entry type so there is nothing else to check. Note
1075 // that this style of checking will consider resolved/unresolved
1076 // class pairs as different.
1077 // From the ConstantPool* API point of view, this is correct
1078 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1079 // plays out in the context of ConstantPool* merging.
1080 return false;
1081 }
1082
1083 switch (t1) {
1084 case JVM_CONSTANT_Class:
1085 {
1086 Klass* k1 = klass_at(index1, CHECK_false);
1087 Klass* k2 = cp2->klass_at(index2, CHECK_false);
1088 if (k1 == k2) {
1089 return true;
1090 }
1091 } break;
1092
1093 case JVM_CONSTANT_ClassIndex:
1094 {
1095 int recur1 = klass_index_at(index1);
1096 int recur2 = cp2->klass_index_at(index2);
1097 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1098 if (match) {
1099 return true;
1100 }
1101 } break;
1102
1103 case JVM_CONSTANT_Double:
1104 {
1105 jdouble d1 = double_at(index1);
1106 jdouble d2 = cp2->double_at(index2);
1107 if (d1 == d2) {
1108 return true;
1109 }
1110 } break;
1111
1112 case JVM_CONSTANT_Fieldref:
1113 case JVM_CONSTANT_InterfaceMethodref:
1114 case JVM_CONSTANT_Methodref:
1115 {
1116 int recur1 = uncached_klass_ref_index_at(index1);
1117 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1118 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1119 if (match) {
1120 recur1 = uncached_name_and_type_ref_index_at(index1);
1121 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1122 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1123 if (match) {
1124 return true;
1125 }
1126 }
1127 } break;
1128
1129 case JVM_CONSTANT_Float:
1130 {
1131 jfloat f1 = float_at(index1);
1132 jfloat f2 = cp2->float_at(index2);
1133 if (f1 == f2) {
1134 return true;
1135 }
1136 } break;
1137
1138 case JVM_CONSTANT_Integer:
1139 {
1140 jint i1 = int_at(index1);
1141 jint i2 = cp2->int_at(index2);
1142 if (i1 == i2) {
1143 return true;
1144 }
1145 } break;
1146
1147 case JVM_CONSTANT_Long:
1148 {
1149 jlong l1 = long_at(index1);
1150 jlong l2 = cp2->long_at(index2);
1151 if (l1 == l2) {
1152 return true;
1153 }
1154 } break;
1155
1156 case JVM_CONSTANT_NameAndType:
1157 {
1158 int recur1 = name_ref_index_at(index1);
1159 int recur2 = cp2->name_ref_index_at(index2);
1160 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1161 if (match) {
1162 recur1 = signature_ref_index_at(index1);
1163 recur2 = cp2->signature_ref_index_at(index2);
1164 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1165 if (match) {
1166 return true;
1167 }
1168 }
1169 } break;
1170
1171 case JVM_CONSTANT_StringIndex:
1172 {
1173 int recur1 = string_index_at(index1);
1174 int recur2 = cp2->string_index_at(index2);
1175 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1176 if (match) {
1177 return true;
1178 }
1179 } break;
1180
1181 case JVM_CONSTANT_UnresolvedClass:
1182 {
1183 Symbol* k1 = klass_name_at(index1);
1184 Symbol* k2 = cp2->klass_name_at(index2);
1185 if (k1 == k2) {
1186 return true;
1187 }
1188 } break;
1189
1190 case JVM_CONSTANT_MethodType:
1191 {
1192 int k1 = method_type_index_at(index1);
1193 int k2 = cp2->method_type_index_at(index2);
1194 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1195 if (match) {
1196 return true;
1197 }
1198 } break;
1199
1200 case JVM_CONSTANT_MethodHandle:
1201 {
1202 int k1 = method_handle_ref_kind_at(index1);
1203 int k2 = cp2->method_handle_ref_kind_at(index2);
1204 if (k1 == k2) {
1205 int i1 = method_handle_index_at(index1);
1206 int i2 = cp2->method_handle_index_at(index2);
1207 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1208 if (match) {
1209 return true;
1210 }
1211 }
1212 } break;
1213
1214 case JVM_CONSTANT_InvokeDynamic:
1215 {
1216 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1217 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1218 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1219 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1220 // separate statements and variables because CHECK_false is used
1221 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1222 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1223 return (match_entry && match_operand);
1224 } break;
1225
1226 case JVM_CONSTANT_String:
1227 {
1228 Symbol* s1 = unresolved_string_at(index1);
1229 Symbol* s2 = cp2->unresolved_string_at(index2);
1230 if (s1 == s2) {
1231 return true;
1232 }
1233 } break;
1234
1235 case JVM_CONSTANT_Utf8:
1236 {
1237 Symbol* s1 = symbol_at(index1);
1238 Symbol* s2 = cp2->symbol_at(index2);
1239 if (s1 == s2) {
1240 return true;
1241 }
1242 } break;
1243
1244 // Invalid is used as the tag for the second constant pool entry
1245 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1246 // not be seen by itself.
1247 case JVM_CONSTANT_Invalid: // fall through
1248
1249 default:
1250 ShouldNotReachHere();
1251 break;
1252 }
1253
1254 return false;
1255 } // end compare_entry_to()
1256
1257
1258 // Resize the operands array with delta_len and delta_size.
1259 // Used in RedefineClasses for CP merge.
1260 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1261 int old_len = operand_array_length(operands());
1262 int new_len = old_len + delta_len;
1263 int min_len = (delta_len > 0) ? old_len : new_len;
1264
1265 int old_size = operands()->length();
1266 int new_size = old_size + delta_size;
1267 int min_size = (delta_size > 0) ? old_size : new_size;
1268
1269 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1270 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1271
1272 // Set index in the resized array for existing elements only
1273 for (int idx = 0; idx < min_len; idx++) {
1274 int offset = operand_offset_at(idx); // offset in original array
1275 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1276 }
1277 // Copy the bootstrap specifiers only
1278 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1279 new_ops->adr_at(2*new_len),
1280 (min_size - 2*min_len) * sizeof(u2));
1281 // Explicitly deallocate old operands array.
1282 // Note, it is not needed for 7u backport.
1283 if ( operands() != NULL) { // the safety check
1284 MetadataFactory::free_array<u2>(loader_data, operands());
1285 }
1286 set_operands(new_ops);
1287 } // end resize_operands()
1288
1289
1290 // Extend the operands array with the length and size of the ext_cp operands.
1291 // Used in RedefineClasses for CP merge.
1292 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1293 int delta_len = operand_array_length(ext_cp->operands());
1294 if (delta_len == 0) {
1295 return; // nothing to do
1296 }
1297 int delta_size = ext_cp->operands()->length();
1298
1299 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1300
1301 if (operand_array_length(operands()) == 0) {
1302 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1303 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1304 // The first element index defines the offset of second part
1305 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1306 set_operands(new_ops);
1307 } else {
1308 resize_operands(delta_len, delta_size, CHECK);
1309 }
1310
1311 } // end extend_operands()
1312
1313
1314 // Shrink the operands array to a smaller array with new_len length.
1315 // Used in RedefineClasses for CP merge.
1316 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1317 int old_len = operand_array_length(operands());
1318 if (new_len == old_len) {
1319 return; // nothing to do
1320 }
1321 assert(new_len < old_len, "shrunken operands array must be smaller");
1322
1323 int free_base = operand_next_offset_at(new_len - 1);
1324 int delta_len = new_len - old_len;
1325 int delta_size = 2*delta_len + free_base - operands()->length();
1326
1327 resize_operands(delta_len, delta_size, CHECK);
1328
1329 } // end shrink_operands()
1330
1331
1332 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1333 const constantPoolHandle& to_cp,
1334 TRAPS) {
1335
1336 int from_oplen = operand_array_length(from_cp->operands());
1337 int old_oplen = operand_array_length(to_cp->operands());
1338 if (from_oplen != 0) {
1339 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1340 // append my operands to the target's operands array
1341 if (old_oplen == 0) {
1342 // Can't just reuse from_cp's operand list because of deallocation issues
1343 int len = from_cp->operands()->length();
1344 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1345 Copy::conjoint_memory_atomic(
1346 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1347 to_cp->set_operands(new_ops);
1348 } else {
1349 int old_len = to_cp->operands()->length();
1350 int from_len = from_cp->operands()->length();
1351 int old_off = old_oplen * sizeof(u2);
1352 int from_off = from_oplen * sizeof(u2);
1353 // Use the metaspace for the destination constant pool
1354 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1355 int fillp = 0, len = 0;
1356 // first part of dest
1357 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1358 new_operands->adr_at(fillp),
1359 (len = old_off) * sizeof(u2));
1360 fillp += len;
1361 // first part of src
1362 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1363 new_operands->adr_at(fillp),
1364 (len = from_off) * sizeof(u2));
1365 fillp += len;
1366 // second part of dest
1367 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1368 new_operands->adr_at(fillp),
1369 (len = old_len - old_off) * sizeof(u2));
1370 fillp += len;
1371 // second part of src
1372 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1373 new_operands->adr_at(fillp),
1374 (len = from_len - from_off) * sizeof(u2));
1375 fillp += len;
1376 assert(fillp == new_operands->length(), "");
1377
1378 // Adjust indexes in the first part of the copied operands array.
1379 for (int j = 0; j < from_oplen; j++) {
1380 int offset = operand_offset_at(new_operands, old_oplen + j);
1381 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1382 offset += old_len; // every new tuple is preceded by old_len extra u2's
1383 operand_offset_at_put(new_operands, old_oplen + j, offset);
1384 }
1385
1386 // replace target operands array with combined array
1387 to_cp->set_operands(new_operands);
1388 }
1389 }
1390 } // end copy_operands()
1391
1392
1393 // Copy this constant pool's entries at start_i to end_i (inclusive)
1394 // to the constant pool to_cp's entries starting at to_i. A total of
1395 // (end_i - start_i) + 1 entries are copied.
1396 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1397 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1398
1399
1400 int dest_i = to_i; // leave original alone for debug purposes
1401
1402 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1403 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1404
1405 switch (from_cp->tag_at(src_i).value()) {
1406 case JVM_CONSTANT_Double:
1407 case JVM_CONSTANT_Long:
1408 // double and long take two constant pool entries
1409 src_i += 2;
1410 dest_i += 2;
1411 break;
1412
1413 default:
1414 // all others take one constant pool entry
1415 src_i++;
1416 dest_i++;
1417 break;
1418 }
1419 }
1420 copy_operands(from_cp, to_cp, CHECK);
1421
1422 } // end copy_cp_to_impl()
1423
1424
1425 // Copy this constant pool's entry at from_i to the constant pool
1426 // to_cp's entry at to_i.
1427 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1428 const constantPoolHandle& to_cp, int to_i,
1429 TRAPS) {
1430
1431 int tag = from_cp->tag_at(from_i).value();
1432 switch (tag) {
1433 case JVM_CONSTANT_ClassIndex:
1434 {
1435 jint ki = from_cp->klass_index_at(from_i);
1436 to_cp->klass_index_at_put(to_i, ki);
1437 } break;
1438
1439 case JVM_CONSTANT_Double:
1440 {
1441 jdouble d = from_cp->double_at(from_i);
1442 to_cp->double_at_put(to_i, d);
1443 // double takes two constant pool entries so init second entry's tag
1444 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1445 } break;
1446
1447 case JVM_CONSTANT_Fieldref:
1448 {
1449 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1450 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1451 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1452 } break;
1453
1454 case JVM_CONSTANT_Float:
1455 {
1456 jfloat f = from_cp->float_at(from_i);
1457 to_cp->float_at_put(to_i, f);
1458 } break;
1459
1460 case JVM_CONSTANT_Integer:
1461 {
1462 jint i = from_cp->int_at(from_i);
1463 to_cp->int_at_put(to_i, i);
1464 } break;
1465
1466 case JVM_CONSTANT_InterfaceMethodref:
1467 {
1468 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1469 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1470 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1471 } break;
1472
1473 case JVM_CONSTANT_Long:
1474 {
1475 jlong l = from_cp->long_at(from_i);
1476 to_cp->long_at_put(to_i, l);
1477 // long takes two constant pool entries so init second entry's tag
1478 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1479 } break;
1480
1481 case JVM_CONSTANT_Methodref:
1482 {
1483 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1484 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1485 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1486 } break;
1487
1488 case JVM_CONSTANT_NameAndType:
1489 {
1490 int name_ref_index = from_cp->name_ref_index_at(from_i);
1491 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1492 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1493 } break;
1494
1495 case JVM_CONSTANT_StringIndex:
1496 {
1497 jint si = from_cp->string_index_at(from_i);
1498 to_cp->string_index_at_put(to_i, si);
1499 } break;
1500
1501 case JVM_CONSTANT_Class:
1502 case JVM_CONSTANT_UnresolvedClass:
1503 case JVM_CONSTANT_UnresolvedClassInError:
1504 {
1505 // Revert to JVM_CONSTANT_ClassIndex
1506 int name_index = from_cp->klass_slot_at(from_i).name_index();
1507 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1508 to_cp->klass_index_at_put(to_i, name_index);
1509 } break;
1510
1511 case JVM_CONSTANT_String:
1512 {
1513 Symbol* s = from_cp->unresolved_string_at(from_i);
1514 to_cp->unresolved_string_at_put(to_i, s);
1515 } break;
1516
1517 case JVM_CONSTANT_Utf8:
1518 {
1519 Symbol* s = from_cp->symbol_at(from_i);
1520 // Need to increase refcount, the old one will be thrown away and deferenced
1521 s->increment_refcount();
1522 to_cp->symbol_at_put(to_i, s);
1523 } break;
1524
1525 case JVM_CONSTANT_MethodType:
1526 case JVM_CONSTANT_MethodTypeInError:
1527 {
1528 jint k = from_cp->method_type_index_at(from_i);
1529 to_cp->method_type_index_at_put(to_i, k);
1530 } break;
1531
1532 case JVM_CONSTANT_MethodHandle:
1533 case JVM_CONSTANT_MethodHandleInError:
1534 {
1535 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1536 int k2 = from_cp->method_handle_index_at(from_i);
1537 to_cp->method_handle_index_at_put(to_i, k1, k2);
1538 } break;
1539
1540 case JVM_CONSTANT_InvokeDynamic:
1541 {
1542 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1543 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1544 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1545 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1546 } break;
1547
1548 // Invalid is used as the tag for the second constant pool entry
1549 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1550 // not be seen by itself.
1551 case JVM_CONSTANT_Invalid: // fall through
1552
1553 default:
1554 {
1555 ShouldNotReachHere();
1556 } break;
1557 }
1558 } // end copy_entry_to()
1559
1560 // Search constant pool search_cp for an entry that matches this
1561 // constant pool's entry at pattern_i. Returns the index of a
1562 // matching entry or zero (0) if there is no matching entry.
1563 int ConstantPool::find_matching_entry(int pattern_i,
1564 const constantPoolHandle& search_cp, TRAPS) {
1565
1566 // index zero (0) is not used
1567 for (int i = 1; i < search_cp->length(); i++) {
1568 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1569 if (found) {
1570 return i;
1571 }
1572 }
1573
1574 return 0; // entry not found; return unused index zero (0)
1575 } // end find_matching_entry()
1576
1577
1578 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1579 // cp2's bootstrap specifier at idx2.
1580 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1581 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1582 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1583 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1584
1585 if (!match) {
1586 return false;
1587 }
1588 int argc = operand_argument_count_at(idx1);
1589 if (argc == cp2->operand_argument_count_at(idx2)) {
1590 for (int j = 0; j < argc; j++) {
1591 k1 = operand_argument_index_at(idx1, j);
1592 k2 = cp2->operand_argument_index_at(idx2, j);
1593 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1594 if (!match) {
1595 return false;
1596 }
1597 }
1598 return true; // got through loop; all elements equal
1599 }
1600 return false;
1601 } // end compare_operand_to()
1602
1603 // Search constant pool search_cp for a bootstrap specifier that matches
1604 // this constant pool's bootstrap specifier at pattern_i index.
1605 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1606 int ConstantPool::find_matching_operand(int pattern_i,
1607 const constantPoolHandle& search_cp, int search_len, TRAPS) {
1608 for (int i = 0; i < search_len; i++) {
1609 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1610 if (found) {
1611 return i;
1612 }
1613 }
1614 return -1; // bootstrap specifier not found; return unused index (-1)
1615 } // end find_matching_operand()
1616
1617
1618 #ifndef PRODUCT
1619
1620 const char* ConstantPool::printable_name_at(int which) {
1621
1622 constantTag tag = tag_at(which);
1623
1624 if (tag.is_string()) {
1625 return string_at_noresolve(which);
1626 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1627 return klass_name_at(which)->as_C_string();
1628 } else if (tag.is_symbol()) {
1629 return symbol_at(which)->as_C_string();
1630 }
1631 return "";
1632 }
1633
1634 #endif // PRODUCT
1635
1636
1637 // JVMTI GetConstantPool support
1638
1639 // For debugging of constant pool
1640 const bool debug_cpool = false;
1641
1642 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1643
1644 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1645 const char* WARN_MSG = "Must not be such entry!";
1646 jint size = 0;
1647 u2 idx1, idx2;
1648
1649 for (jint idx = 1; idx < cnt; idx++) {
1650 jint ent_size = 0;
1651 u1 tag = *bytes++;
1652 size++; // count tag
1653
1654 printf("const #%03d, tag: %02d ", idx, tag);
1655 switch(tag) {
1656 case JVM_CONSTANT_Invalid: {
1657 printf("Invalid");
1658 break;
1659 }
1660 case JVM_CONSTANT_Unicode: {
1661 printf("Unicode %s", WARN_MSG);
1662 break;
1663 }
1664 case JVM_CONSTANT_Utf8: {
1665 u2 len = Bytes::get_Java_u2(bytes);
1666 char str[128];
1667 if (len > 127) {
1668 len = 127;
1669 }
1670 strncpy(str, (char *) (bytes+2), len);
1671 str[len] = '\0';
1672 printf("Utf8 \"%s\"", str);
1673 ent_size = 2 + len;
1674 break;
1675 }
1676 case JVM_CONSTANT_Integer: {
1677 u4 val = Bytes::get_Java_u4(bytes);
1678 printf("int %d", *(int *) &val);
1679 ent_size = 4;
1680 break;
1681 }
1682 case JVM_CONSTANT_Float: {
1683 u4 val = Bytes::get_Java_u4(bytes);
1684 printf("float %5.3ff", *(float *) &val);
1685 ent_size = 4;
1686 break;
1687 }
1688 case JVM_CONSTANT_Long: {
1689 u8 val = Bytes::get_Java_u8(bytes);
1690 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1691 ent_size = 8;
1692 idx++; // Long takes two cpool slots
1693 break;
1694 }
1695 case JVM_CONSTANT_Double: {
1696 u8 val = Bytes::get_Java_u8(bytes);
1697 printf("double %5.3fd", *(jdouble *)&val);
1698 ent_size = 8;
1699 idx++; // Double takes two cpool slots
1700 break;
1701 }
1702 case JVM_CONSTANT_Class: {
1703 idx1 = Bytes::get_Java_u2(bytes);
1704 printf("class #%03d", idx1);
1705 ent_size = 2;
1706 break;
1707 }
1708 case JVM_CONSTANT_String: {
1709 idx1 = Bytes::get_Java_u2(bytes);
1710 printf("String #%03d", idx1);
1711 ent_size = 2;
1712 break;
1713 }
1714 case JVM_CONSTANT_Fieldref: {
1715 idx1 = Bytes::get_Java_u2(bytes);
1716 idx2 = Bytes::get_Java_u2(bytes+2);
1717 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1718 ent_size = 4;
1719 break;
1720 }
1721 case JVM_CONSTANT_Methodref: {
1722 idx1 = Bytes::get_Java_u2(bytes);
1723 idx2 = Bytes::get_Java_u2(bytes+2);
1724 printf("Method #%03d, #%03d", idx1, idx2);
1725 ent_size = 4;
1726 break;
1727 }
1728 case JVM_CONSTANT_InterfaceMethodref: {
1729 idx1 = Bytes::get_Java_u2(bytes);
1730 idx2 = Bytes::get_Java_u2(bytes+2);
1731 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1732 ent_size = 4;
1733 break;
1734 }
1735 case JVM_CONSTANT_NameAndType: {
1736 idx1 = Bytes::get_Java_u2(bytes);
1737 idx2 = Bytes::get_Java_u2(bytes+2);
1738 printf("NameAndType #%03d, #%03d", idx1, idx2);
1739 ent_size = 4;
1740 break;
1741 }
1742 case JVM_CONSTANT_ClassIndex: {
1743 printf("ClassIndex %s", WARN_MSG);
1744 break;
1745 }
1746 case JVM_CONSTANT_UnresolvedClass: {
1747 printf("UnresolvedClass: %s", WARN_MSG);
1748 break;
1749 }
1750 case JVM_CONSTANT_UnresolvedClassInError: {
1751 printf("UnresolvedClassInErr: %s", WARN_MSG);
1752 break;
1753 }
1754 case JVM_CONSTANT_StringIndex: {
1755 printf("StringIndex: %s", WARN_MSG);
1756 break;
1757 }
1758 }
1759 printf(";\n");
1760 bytes += ent_size;
1761 size += ent_size;
1762 }
1763 printf("Cpool size: %d\n", size);
1764 fflush(0);
1765 return;
1766 } /* end print_cpool_bytes */
1767
1768
1769 // Returns size of constant pool entry.
1770 jint ConstantPool::cpool_entry_size(jint idx) {
1771 switch(tag_at(idx).value()) {
1772 case JVM_CONSTANT_Invalid:
1773 case JVM_CONSTANT_Unicode:
1774 return 1;
1775
1776 case JVM_CONSTANT_Utf8:
1777 return 3 + symbol_at(idx)->utf8_length();
1778
1779 case JVM_CONSTANT_Class:
1780 case JVM_CONSTANT_String:
1781 case JVM_CONSTANT_ClassIndex:
1782 case JVM_CONSTANT_UnresolvedClass:
1783 case JVM_CONSTANT_UnresolvedClassInError:
1784 case JVM_CONSTANT_StringIndex:
1785 case JVM_CONSTANT_MethodType:
1786 case JVM_CONSTANT_MethodTypeInError:
1787 return 3;
1788
1789 case JVM_CONSTANT_MethodHandle:
1790 case JVM_CONSTANT_MethodHandleInError:
1791 return 4; //tag, ref_kind, ref_index
1792
1793 case JVM_CONSTANT_Integer:
1794 case JVM_CONSTANT_Float:
1795 case JVM_CONSTANT_Fieldref:
1796 case JVM_CONSTANT_Methodref:
1797 case JVM_CONSTANT_InterfaceMethodref:
1798 case JVM_CONSTANT_NameAndType:
1799 return 5;
1800
1801 case JVM_CONSTANT_InvokeDynamic:
1802 // u1 tag, u2 bsm, u2 nt
1803 return 5;
1804
1805 case JVM_CONSTANT_Long:
1806 case JVM_CONSTANT_Double:
1807 return 9;
1808 }
1809 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1810 return 1;
1811 } /* end cpool_entry_size */
1812
1813
1814 // SymbolHashMap is used to find a constant pool index from a string.
1815 // This function fills in SymbolHashMaps, one for utf8s and one for
1816 // class names, returns size of the cpool raw bytes.
1817 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1818 SymbolHashMap *classmap) {
1819 jint size = 0;
1820
1821 for (u2 idx = 1; idx < length(); idx++) {
1822 u2 tag = tag_at(idx).value();
1823 size += cpool_entry_size(idx);
1824
1825 switch(tag) {
1826 case JVM_CONSTANT_Utf8: {
1827 Symbol* sym = symbol_at(idx);
1828 symmap->add_entry(sym, idx);
1829 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1830 break;
1831 }
1832 case JVM_CONSTANT_Class:
1833 case JVM_CONSTANT_UnresolvedClass:
1834 case JVM_CONSTANT_UnresolvedClassInError: {
1835 Symbol* sym = klass_name_at(idx);
1836 classmap->add_entry(sym, idx);
1837 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1838 break;
1839 }
1840 case JVM_CONSTANT_Long:
1841 case JVM_CONSTANT_Double: {
1842 idx++; // Both Long and Double take two cpool slots
1843 break;
1844 }
1845 }
1846 }
1847 return size;
1848 } /* end hash_utf8_entries_to */
1849
1850
1851 // Copy cpool bytes.
1852 // Returns:
1853 // 0, in case of OutOfMemoryError
1854 // -1, in case of internal error
1855 // > 0, count of the raw cpool bytes that have been copied
1856 int ConstantPool::copy_cpool_bytes(int cpool_size,
1857 SymbolHashMap* tbl,
1858 unsigned char *bytes) {
1859 u2 idx1, idx2;
1860 jint size = 0;
1861 jint cnt = length();
1862 unsigned char *start_bytes = bytes;
1863
1864 for (jint idx = 1; idx < cnt; idx++) {
1865 u1 tag = tag_at(idx).value();
1866 jint ent_size = cpool_entry_size(idx);
1867
1868 assert(size + ent_size <= cpool_size, "Size mismatch");
1869
1870 *bytes = tag;
1871 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
1872 switch(tag) {
1873 case JVM_CONSTANT_Invalid: {
1874 DBG(printf("JVM_CONSTANT_Invalid"));
1875 break;
1876 }
1877 case JVM_CONSTANT_Unicode: {
1878 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1879 DBG(printf("JVM_CONSTANT_Unicode"));
1880 break;
1881 }
1882 case JVM_CONSTANT_Utf8: {
1883 Symbol* sym = symbol_at(idx);
1884 char* str = sym->as_utf8();
1885 // Warning! It's crashing on x86 with len = sym->utf8_length()
1886 int len = (int) strlen(str);
1887 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1888 for (int i = 0; i < len; i++) {
1889 bytes[3+i] = (u1) str[i];
1890 }
1891 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1892 break;
1893 }
1894 case JVM_CONSTANT_Integer: {
1895 jint val = int_at(idx);
1896 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1897 break;
1898 }
1899 case JVM_CONSTANT_Float: {
1900 jfloat val = float_at(idx);
1901 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1902 break;
1903 }
1904 case JVM_CONSTANT_Long: {
1905 jlong val = long_at(idx);
1906 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1907 idx++; // Long takes two cpool slots
1908 break;
1909 }
1910 case JVM_CONSTANT_Double: {
1911 jdouble val = double_at(idx);
1912 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1913 idx++; // Double takes two cpool slots
1914 break;
1915 }
1916 case JVM_CONSTANT_Class:
1917 case JVM_CONSTANT_UnresolvedClass:
1918 case JVM_CONSTANT_UnresolvedClassInError: {
1919 *bytes = JVM_CONSTANT_Class;
1920 Symbol* sym = klass_name_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_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1925 break;
1926 }
1927 case JVM_CONSTANT_String: {
1928 *bytes = JVM_CONSTANT_String;
1929 Symbol* sym = unresolved_string_at(idx);
1930 idx1 = tbl->symbol_to_value(sym);
1931 assert(idx1 != 0, "Have not found a hashtable entry");
1932 Bytes::put_Java_u2((address) (bytes+1), idx1);
1933 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1934 break;
1935 }
1936 case JVM_CONSTANT_Fieldref:
1937 case JVM_CONSTANT_Methodref:
1938 case JVM_CONSTANT_InterfaceMethodref: {
1939 idx1 = uncached_klass_ref_index_at(idx);
1940 idx2 = uncached_name_and_type_ref_index_at(idx);
1941 Bytes::put_Java_u2((address) (bytes+1), idx1);
1942 Bytes::put_Java_u2((address) (bytes+3), idx2);
1943 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1944 break;
1945 }
1946 case JVM_CONSTANT_NameAndType: {
1947 idx1 = name_ref_index_at(idx);
1948 idx2 = signature_ref_index_at(idx);
1949 Bytes::put_Java_u2((address) (bytes+1), idx1);
1950 Bytes::put_Java_u2((address) (bytes+3), idx2);
1951 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1952 break;
1953 }
1954 case JVM_CONSTANT_ClassIndex: {
1955 *bytes = JVM_CONSTANT_Class;
1956 idx1 = klass_index_at(idx);
1957 Bytes::put_Java_u2((address) (bytes+1), idx1);
1958 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1959 break;
1960 }
1961 case JVM_CONSTANT_StringIndex: {
1962 *bytes = JVM_CONSTANT_String;
1963 idx1 = string_index_at(idx);
1964 Bytes::put_Java_u2((address) (bytes+1), idx1);
1965 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1966 break;
1967 }
1968 case JVM_CONSTANT_MethodHandle:
1969 case JVM_CONSTANT_MethodHandleInError: {
1970 *bytes = JVM_CONSTANT_MethodHandle;
1971 int kind = method_handle_ref_kind_at(idx);
1972 idx1 = method_handle_index_at(idx);
1973 *(bytes+1) = (unsigned char) kind;
1974 Bytes::put_Java_u2((address) (bytes+2), idx1);
1975 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1976 break;
1977 }
1978 case JVM_CONSTANT_MethodType:
1979 case JVM_CONSTANT_MethodTypeInError: {
1980 *bytes = JVM_CONSTANT_MethodType;
1981 idx1 = method_type_index_at(idx);
1982 Bytes::put_Java_u2((address) (bytes+1), idx1);
1983 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1984 break;
1985 }
1986 case JVM_CONSTANT_InvokeDynamic: {
1987 *bytes = tag;
1988 idx1 = extract_low_short_from_int(*int_at_addr(idx));
1989 idx2 = extract_high_short_from_int(*int_at_addr(idx));
1990 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1991 Bytes::put_Java_u2((address) (bytes+1), idx1);
1992 Bytes::put_Java_u2((address) (bytes+3), idx2);
1993 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1994 break;
1995 }
1996 }
1997 DBG(printf("\n"));
1998 bytes += ent_size;
1999 size += ent_size;
2000 }
2001 assert(size == cpool_size, "Size mismatch");
2002
2003 // Keep temorarily for debugging until it's stable.
2004 DBG(print_cpool_bytes(cnt, start_bytes));
2005 return (int)(bytes - start_bytes);
2006 } /* end copy_cpool_bytes */
2007
2008 #undef DBG
2009
2010
2011 void ConstantPool::set_on_stack(const bool value) {
2012 if (value) {
2013 // Only record if it's not already set.
2014 if (!on_stack()) {
2015 assert(!is_shared(), "should always be set for shared constant pools");
2016 _flags |= _on_stack;
2017 MetadataOnStackMark::record(this);
2018 }
2019 } else {
2020 // Clearing is done single-threadedly.
2021 if (!is_shared()) {
2022 _flags &= ~_on_stack;
2023 }
2024 }
2025 }
2026
2027 // JSR 292 support for patching constant pool oops after the class is linked and
2028 // the oop array for resolved references are created.
2029 // We can't do this during classfile parsing, which is how the other indexes are
2030 // patched. The other patches are applied early for some error checking
2031 // so only defer the pseudo_strings.
2032 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
2033 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
2034 Handle patch = cp_patches->at(index);
2035 if (patch.not_null()) {
2036 assert (tag_at(index).is_string(), "should only be string left");
2037 // Patching a string means pre-resolving it.
2038 // The spelling in the constant pool is ignored.
2039 // The constant reference may be any object whatever.
2040 // If it is not a real interned string, the constant is referred
2041 // to as a "pseudo-string", and must be presented to the CP
2042 // explicitly, because it may require scavenging.
2043 int obj_index = cp_to_object_index(index);
2044 pseudo_string_at_put(index, obj_index, patch());
2045 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
2046 }
2047 }
2048 #ifdef ASSERT
2049 // Ensure that all the patches have been used.
2050 for (int index = 0; index < cp_patches->length(); index++) {
2051 assert(cp_patches->at(index).is_null(),
2052 "Unused constant pool patch at %d in class file %s",
2053 index,
2054 pool_holder()->external_name());
2055 }
2056 #endif // ASSERT
2057 }
2058
2059 #ifndef PRODUCT
2060
2061 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
2062 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
2063 guarantee(obj->is_constantPool(), "object must be constant pool");
2064 constantPoolHandle cp(THREAD, (ConstantPool*)obj);
2065 guarantee(cp->pool_holder() != NULL, "must be fully loaded");
2066
2067 for (int i = 0; i< cp->length(); i++) {
2068 if (cp->tag_at(i).is_unresolved_klass()) {
2069 // This will force loading of the class
2070 Klass* klass = cp->klass_at(i, CHECK);
2071 if (klass->is_instance_klass()) {
2072 // Force initialization of class
2073 InstanceKlass::cast(klass)->initialize(CHECK);
2074 }
2075 }
2076 }
2077 }
2078
2079 #endif
2080
2081
2082 // Printing
2083
2084 void ConstantPool::print_on(outputStream* st) const {
2085 assert(is_constantPool(), "must be constantPool");
2086 st->print_cr("%s", internal_name());
2087 if (flags() != 0) {
2088 st->print(" - flags: 0x%x", flags());
2089 if (has_preresolution()) st->print(" has_preresolution");
2090 if (on_stack()) st->print(" on_stack");
2091 st->cr();
2092 }
2093 if (pool_holder() != NULL) {
2094 st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
2095 }
2096 st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
2097 st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
2098 st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
2099 st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
2100
2101 for (int index = 1; index < length(); index++) { // Index 0 is unused
2102 ((ConstantPool*)this)->print_entry_on(index, st);
2103 switch (tag_at(index).value()) {
2104 case JVM_CONSTANT_Long :
2105 case JVM_CONSTANT_Double :
2106 index++; // Skip entry following eigth-byte constant
2107 }
2108
2109 }
2110 st->cr();
2111 }
2112
2113 // Print one constant pool entry
2114 void ConstantPool::print_entry_on(const int index, outputStream* st) {
2115 EXCEPTION_MARK;
2116 st->print(" - %3d : ", index);
2117 tag_at(index).print_on(st);
2118 st->print(" : ");
2119 switch (tag_at(index).value()) {
2120 case JVM_CONSTANT_Class :
2121 { Klass* k = klass_at(index, CATCH);
2122 guarantee(k != NULL, "need klass");
2123 k->print_value_on(st);
2124 st->print(" {" PTR_FORMAT "}", p2i(k));
2125 }
2126 break;
2127 case JVM_CONSTANT_Fieldref :
2128 case JVM_CONSTANT_Methodref :
2129 case JVM_CONSTANT_InterfaceMethodref :
2130 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
2131 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
2132 break;
2133 case JVM_CONSTANT_String :
2134 if (is_pseudo_string_at(index)) {
2135 oop anObj = pseudo_string_at(index);
2136 anObj->print_value_on(st);
2137 st->print(" {" PTR_FORMAT "}", p2i(anObj));
2138 } else {
2139 unresolved_string_at(index)->print_value_on(st);
2140 }
2141 break;
2142 case JVM_CONSTANT_Integer :
2143 st->print("%d", int_at(index));
2144 break;
2145 case JVM_CONSTANT_Float :
2146 st->print("%f", float_at(index));
2147 break;
2148 case JVM_CONSTANT_Long :
2149 st->print_jlong(long_at(index));
2150 break;
2151 case JVM_CONSTANT_Double :
2152 st->print("%lf", double_at(index));
2153 break;
2154 case JVM_CONSTANT_NameAndType :
2155 st->print("name_index=%d", name_ref_index_at(index));
2156 st->print(" signature_index=%d", signature_ref_index_at(index));
2157 break;
2158 case JVM_CONSTANT_Utf8 :
2159 symbol_at(index)->print_value_on(st);
2160 break;
2161 case JVM_CONSTANT_ClassIndex: {
2162 int name_index = *int_at_addr(index);
2163 st->print("klass_index=%d ", name_index);
2164 symbol_at(name_index)->print_value_on(st);
2165 }
2166 break;
2167 case JVM_CONSTANT_UnresolvedClass : // fall-through
2168 case JVM_CONSTANT_UnresolvedClassInError: {
2169 CPKlassSlot kslot = klass_slot_at(index);
2170 int resolved_klass_index = kslot.resolved_klass_index();
2171 int name_index = kslot.name_index();
2172 assert(tag_at(name_index).is_symbol(), "sanity");
2173
2174 Klass* klass = resolved_klasses()->at(resolved_klass_index);
2175 if (klass != NULL) {
2176 klass->print_value_on(st);
2177 } else {
2178 symbol_at(name_index)->print_value_on(st);
2179 }
2180 }
2181 break;
2182 case JVM_CONSTANT_MethodHandle :
2183 case JVM_CONSTANT_MethodHandleInError :
2184 st->print("ref_kind=%d", method_handle_ref_kind_at(index));
2185 st->print(" ref_index=%d", method_handle_index_at(index));
2186 break;
2187 case JVM_CONSTANT_MethodType :
2188 case JVM_CONSTANT_MethodTypeInError :
2189 st->print("signature_index=%d", method_type_index_at(index));
2190 break;
2191 case JVM_CONSTANT_InvokeDynamic :
2192 {
2193 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2194 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2195 int argc = invoke_dynamic_argument_count_at(index);
2196 if (argc > 0) {
2197 for (int arg_i = 0; arg_i < argc; arg_i++) {
2198 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2199 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2200 }
2201 st->print("}");
2202 }
2203 }
2204 break;
2205 default:
2206 ShouldNotReachHere();
2207 break;
2208 }
2209 st->cr();
2210 }
2211
2212 void ConstantPool::print_value_on(outputStream* st) const {
2213 assert(is_constantPool(), "must be constantPool");
2214 st->print("constant pool [%d]", length());
2215 if (has_preresolution()) st->print("/preresolution");
2216 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2217 print_address_on(st);
2218 st->print(" for ");
2219 pool_holder()->print_value_on(st);
2220 if (pool_holder() != NULL) {
2221 bool extra = (pool_holder()->constants() != this);
2222 if (extra) st->print(" (extra)");
2223 }
2224 if (cache() != NULL) {
2225 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2226 }
2227 }
2228
2229 #if INCLUDE_SERVICES
2230 // Size Statistics
2231 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2232 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2233 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2234 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2235 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2236 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2237
2238 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2239 sz->_cp_refmap_bytes;
2240 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2241 }
2242 #endif // INCLUDE_SERVICES
2243
2244 // Verification
2245
2246 void ConstantPool::verify_on(outputStream* st) {
2247 guarantee(is_constantPool(), "object must be constant pool");
2248 for (int i = 0; i< length(); i++) {
2249 constantTag tag = tag_at(i);
2250 if (tag.is_klass() || tag.is_unresolved_klass()) {
2251 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2252 } else if (tag.is_symbol()) {
2253 CPSlot entry = slot_at(i);
2254 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2255 } else if (tag.is_string()) {
2256 CPSlot entry = slot_at(i);
2257 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2258 }
2259 }
2260 if (cache() != NULL) {
2261 // Note: cache() can be NULL before a class is completely setup or
2262 // in temporary constant pools used during constant pool merging
2263 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2264 }
2265 if (pool_holder() != NULL) {
2266 // Note: pool_holder() can be NULL in temporary constant pools
2267 // used during constant pool merging
2268 guarantee(pool_holder()->is_klass(), "should be klass");
2269 }
2270 }
2271
2272
2273 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2274 char *str = sym->as_utf8();
2275 unsigned int hash = compute_hash(str, sym->utf8_length());
2276 unsigned int index = hash % table_size();
2277
2278 // check if already in map
2279 // we prefer the first entry since it is more likely to be what was used in
2280 // the class file
2281 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2282 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2283 if (en->hash() == hash && en->symbol() == sym) {
2284 return; // already there
2285 }
2286 }
2287
2288 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2289 entry->set_next(bucket(index));
2290 _buckets[index].set_entry(entry);
2291 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2292 }
2293
2294 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2295 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2296 char *str = sym->as_utf8();
2297 int len = sym->utf8_length();
2298 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2299 unsigned int index = hash % table_size();
2300 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2301 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2302 if (en->hash() == hash && en->symbol() == sym) {
2303 return en;
2304 }
2305 }
2306 return NULL;
2307 }