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