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