1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classLoaderData.hpp"
28 #include "classfile/javaClasses.inline.hpp"
29 #include "classfile/metadataOnStackMark.hpp"
30 #include "classfile/stringTable.hpp"
31 #include "classfile/systemDictionary.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "interpreter/linkResolver.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/heapInspection.hpp"
36 #include "memory/heapShared.hpp"
37 #include "memory/metadataFactory.hpp"
38 #include "memory/metaspaceClosure.hpp"
39 #include "memory/metaspaceShared.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "oops/array.inline.hpp"
43 #include "oops/constantPool.inline.hpp"
44 #include "oops/cpCache.inline.hpp"
45 #include "oops/instanceKlass.hpp"
46 #include "oops/objArrayKlass.hpp"
47 #include "oops/objArrayOop.inline.hpp"
48 #include "oops/oop.inline.hpp"
49 #include "oops/typeArrayOop.inline.hpp"
50 #include "runtime/fieldType.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/init.hpp"
53 #include "runtime/javaCalls.hpp"
54 #include "runtime/signature.hpp"
55 #include "runtime/vframe.inline.hpp"
56 #include "utilities/copy.hpp"
57
tag_at(int which) const58 constantTag ConstantPool::tag_at(int which) const { return (constantTag)tags()->at_acquire(which); }
59
release_tag_at_put(int which,jbyte t)60 void ConstantPool::release_tag_at_put(int which, jbyte t) { tags()->release_at_put(which, t); }
61
allocate(ClassLoaderData * loader_data,int length,TRAPS)62 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
63 Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
64 int size = ConstantPool::size(length);
65 return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
66 }
67
68 #ifdef ASSERT
69
70 // MetaspaceObj allocation invariant is calloc equivalent memory
71 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
tag_array_is_zero_initialized(Array<u1> * tags)72 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
73 assert(tags != NULL, "invariant");
74 const int length = tags->length();
75 for (int index = 0; index < length; ++index) {
76 if (JVM_CONSTANT_Invalid != tags->at(index)) {
77 return false;
78 }
79 }
80 return true;
81 }
82
83 #endif
84
ConstantPool(Array<u1> * tags)85 ConstantPool::ConstantPool(Array<u1>* tags) :
86 _tags(tags),
87 _length(tags->length()) {
88
89 assert(_tags != NULL, "invariant");
90 assert(tags->length() == _length, "invariant");
91 assert(tag_array_is_zero_initialized(tags), "invariant");
92 assert(0 == flags(), "invariant");
93 assert(0 == version(), "invariant");
94 assert(NULL == _pool_holder, "invariant");
95 }
96
deallocate_contents(ClassLoaderData * loader_data)97 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
98 if (cache() != NULL) {
99 MetadataFactory::free_metadata(loader_data, cache());
100 set_cache(NULL);
101 }
102
103 MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
104 set_resolved_klasses(NULL);
105
106 MetadataFactory::free_array<jushort>(loader_data, operands());
107 set_operands(NULL);
108
109 release_C_heap_structures();
110
111 // free tag array
112 MetadataFactory::free_array<u1>(loader_data, tags());
113 set_tags(NULL);
114 }
115
release_C_heap_structures()116 void ConstantPool::release_C_heap_structures() {
117 // walk constant pool and decrement symbol reference counts
118 unreference_symbols();
119 }
120
metaspace_pointers_do(MetaspaceClosure * it)121 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
122 log_trace(cds)("Iter(ConstantPool): %p", this);
123
124 it->push(&_tags, MetaspaceClosure::_writable);
125 it->push(&_cache);
126 it->push(&_pool_holder);
127 it->push(&_operands);
128 it->push(&_resolved_klasses, MetaspaceClosure::_writable);
129
130 for (int i = 0; i < length(); i++) {
131 // The only MSO's embedded in the CP entries are Symbols:
132 // JVM_CONSTANT_String (normal and pseudo)
133 // JVM_CONSTANT_Utf8
134 constantTag ctag = tag_at(i);
135 if (ctag.is_string() || ctag.is_utf8()) {
136 it->push(symbol_at_addr(i));
137 }
138 }
139 }
140
resolved_references() const141 objArrayOop ConstantPool::resolved_references() const {
142 return (objArrayOop)_cache->resolved_references();
143 }
144
145 // Called from outside constant pool resolution where a resolved_reference array
146 // may not be present.
resolved_references_or_null() const147 objArrayOop ConstantPool::resolved_references_or_null() const {
148 if (_cache == NULL) {
149 return NULL;
150 } else {
151 return (objArrayOop)_cache->resolved_references();
152 }
153 }
154
155 // Create resolved_references array and mapping array for original cp indexes
156 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
157 // to map it back for resolving and some unlikely miscellaneous uses.
158 // The objects created by invokedynamic are appended to this list.
initialize_resolved_references(ClassLoaderData * loader_data,const intStack & reference_map,int constant_pool_map_length,TRAPS)159 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
160 const intStack& reference_map,
161 int constant_pool_map_length,
162 TRAPS) {
163 // Initialized the resolved object cache.
164 int map_length = reference_map.length();
165 if (map_length > 0) {
166 // Only need mapping back to constant pool entries. The map isn't used for
167 // invokedynamic resolved_reference entries. For invokedynamic entries,
168 // the constant pool cache index has the mapping back to both the constant
169 // pool and to the resolved reference index.
170 if (constant_pool_map_length > 0) {
171 Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
172
173 for (int i = 0; i < constant_pool_map_length; i++) {
174 int x = reference_map.at(i);
175 assert(x == (int)(jushort) x, "klass index is too big");
176 om->at_put(i, (jushort)x);
177 }
178 set_reference_map(om);
179 }
180
181 // Create Java array for holding resolved strings, methodHandles,
182 // methodTypes, invokedynamic and invokehandle appendix objects, etc.
183 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
184 Handle refs_handle (THREAD, (oop)stom); // must handleize.
185 set_resolved_references(loader_data->add_handle(refs_handle));
186 }
187 }
188
allocate_resolved_klasses(ClassLoaderData * loader_data,int num_klasses,TRAPS)189 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
190 // A ConstantPool can't possibly have 0xffff valid class entries,
191 // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
192 // entry for the class's name. So at most we will have 0xfffe class entries.
193 // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
194 // UnresolvedKlass entries that are temporarily created during class redefinition.
195 assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
196 assert(resolved_klasses() == NULL, "sanity");
197 Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
198 set_resolved_klasses(rk);
199 }
200
initialize_unresolved_klasses(ClassLoaderData * loader_data,TRAPS)201 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
202 int len = length();
203 int num_klasses = 0;
204 for (int i = 1; i <len; i++) {
205 switch (tag_at(i).value()) {
206 case JVM_CONSTANT_ClassIndex:
207 {
208 const int class_index = klass_index_at(i);
209 unresolved_klass_at_put(i, class_index, num_klasses++);
210 }
211 break;
212 #ifndef PRODUCT
213 case JVM_CONSTANT_Class:
214 case JVM_CONSTANT_UnresolvedClass:
215 case JVM_CONSTANT_UnresolvedClassInError:
216 // All of these should have been reverted back to ClassIndex before calling
217 // this function.
218 ShouldNotReachHere();
219 #endif
220 }
221 }
222 allocate_resolved_klasses(loader_data, num_klasses, THREAD);
223 }
224
225 // Unsafe anonymous class support:
klass_at_put(int class_index,int name_index,int resolved_klass_index,Klass * k,Symbol * name)226 void ConstantPool::klass_at_put(int class_index, int name_index, int resolved_klass_index, Klass* k, Symbol* name) {
227 assert(is_within_bounds(class_index), "index out of bounds");
228 assert(is_within_bounds(name_index), "index out of bounds");
229 assert((resolved_klass_index & 0xffff0000) == 0, "must be");
230 *int_at_addr(class_index) =
231 build_int_from_shorts((jushort)resolved_klass_index, (jushort)name_index);
232
233 symbol_at_put(name_index, name);
234 name->increment_refcount();
235 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
236 OrderAccess::release_store(adr, k);
237
238 // The interpreter assumes when the tag is stored, the klass is resolved
239 // and the Klass* non-NULL, so we need hardware store ordering here.
240 if (k != NULL) {
241 release_tag_at_put(class_index, JVM_CONSTANT_Class);
242 } else {
243 release_tag_at_put(class_index, JVM_CONSTANT_UnresolvedClass);
244 }
245 }
246
247 // Unsafe anonymous class support:
klass_at_put(int class_index,Klass * k)248 void ConstantPool::klass_at_put(int class_index, Klass* k) {
249 assert(k != NULL, "must be valid klass");
250 CPKlassSlot kslot = klass_slot_at(class_index);
251 int resolved_klass_index = kslot.resolved_klass_index();
252 Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
253 OrderAccess::release_store(adr, k);
254
255 // The interpreter assumes when the tag is stored, the klass is resolved
256 // and the Klass* non-NULL, so we need hardware store ordering here.
257 release_tag_at_put(class_index, JVM_CONSTANT_Class);
258 }
259
260 #if INCLUDE_CDS_JAVA_HEAP
261 // Archive the resolved references
archive_resolved_references(Thread * THREAD)262 void ConstantPool::archive_resolved_references(Thread* THREAD) {
263 if (_cache == NULL) {
264 return; // nothing to do
265 }
266
267 InstanceKlass *ik = pool_holder();
268 if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
269 ik->is_shared_app_class())) {
270 // Archiving resolved references for classes from non-builtin loaders
271 // is not yet supported.
272 set_resolved_references(NULL);
273 return;
274 }
275
276 objArrayOop rr = resolved_references();
277 Array<u2>* ref_map = reference_map();
278 if (rr != NULL) {
279 int ref_map_len = ref_map == NULL ? 0 : ref_map->length();
280 int rr_len = rr->length();
281 for (int i = 0; i < rr_len; i++) {
282 oop p = rr->obj_at(i);
283 rr->obj_at_put(i, NULL);
284 if (p != NULL && i < ref_map_len) {
285 int index = object_to_cp_index(i);
286 // Skip the entry if the string hash code is 0 since the string
287 // is not included in the shared string_table, see StringTable::copy_shared_string.
288 if (tag_at(index).is_string() && java_lang_String::hash_code(p) != 0) {
289 oop op = StringTable::create_archived_string(p, THREAD);
290 // If the String object is not archived (possibly too large),
291 // NULL is returned. Also set it in the array, so we won't
292 // have a 'bad' reference in the archived resolved_reference
293 // array.
294 rr->obj_at_put(i, op);
295 }
296 }
297 }
298
299 oop archived = HeapShared::archive_heap_object(rr, THREAD);
300 // If the resolved references array is not archived (too large),
301 // the 'archived' object is NULL. No need to explicitly check
302 // the return value of archive_heap_object here. At runtime, the
303 // resolved references will be created using the normal process
304 // when there is no archived value.
305 _cache->set_archived_references(archived);
306 set_resolved_references(NULL);
307 }
308 }
309
resolve_class_constants(TRAPS)310 void ConstantPool::resolve_class_constants(TRAPS) {
311 assert(DumpSharedSpaces, "used during dump time only");
312 // The _cache may be NULL if the _pool_holder klass fails verification
313 // at dump time due to missing dependencies.
314 if (cache() == NULL || reference_map() == NULL) {
315 return; // nothing to do
316 }
317
318 constantPoolHandle cp(THREAD, this);
319 for (int index = 1; index < length(); index++) { // Index 0 is unused
320 if (tag_at(index).is_string() && !cp->is_pseudo_string_at(index)) {
321 int cache_index = cp->cp_to_object_index(index);
322 string_at_impl(cp, index, cache_index, CHECK);
323 }
324 }
325 }
326 #endif
327
328 // CDS support. Create a new resolved_references array.
restore_unshareable_info(TRAPS)329 void ConstantPool::restore_unshareable_info(TRAPS) {
330 assert(is_constantPool(), "ensure C++ vtable is restored");
331 assert(on_stack(), "should always be set for shared constant pools");
332 assert(is_shared(), "should always be set for shared constant pools");
333 assert(_cache != NULL, "constant pool _cache should not be NULL");
334
335 // Only create the new resolved references array if it hasn't been attempted before
336 if (resolved_references() != NULL) return;
337
338 // restore the C++ vtable from the shared archive
339 restore_vtable();
340
341 if (SystemDictionary::Object_klass_loaded()) {
342 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
343 #if INCLUDE_CDS_JAVA_HEAP
344 if (HeapShared::open_archive_heap_region_mapped() &&
345 _cache->archived_references() != NULL) {
346 oop archived = _cache->archived_references();
347 // Create handle for the archived resolved reference array object
348 Handle refs_handle(THREAD, archived);
349 set_resolved_references(loader_data->add_handle(refs_handle));
350 } else
351 #endif
352 {
353 // No mapped archived resolved reference array
354 // Recreate the object array and add to ClassLoaderData.
355 int map_length = resolved_reference_length();
356 if (map_length > 0) {
357 objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
358 Handle refs_handle(THREAD, (oop)stom); // must handleize.
359 set_resolved_references(loader_data->add_handle(refs_handle));
360 }
361 }
362 }
363 }
364
remove_unshareable_info()365 void ConstantPool::remove_unshareable_info() {
366 // Resolved references are not in the shared archive.
367 // Save the length for restoration. It is not necessarily the same length
368 // as reference_map.length() if invokedynamic is saved. It is needed when
369 // re-creating the resolved reference array if archived heap data cannot be map
370 // at runtime.
371 set_resolved_reference_length(
372 resolved_references() != NULL ? resolved_references()->length() : 0);
373
374 // If archiving heap objects is not allowed, clear the resolved references.
375 // Otherwise, it is cleared after the resolved references array is cached
376 // (see archive_resolved_references()).
377 if (!HeapShared::is_heap_object_archiving_allowed()) {
378 set_resolved_references(NULL);
379 }
380
381 // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
382 // The _on_stack flag is used to prevent ConstantPools from deallocation during
383 // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
384 // we always set _on_stack to true to avoid having to change _flags during runtime.
385 _flags |= (_on_stack | _is_shared);
386 int num_klasses = 0;
387 for (int index = 1; index < length(); index++) { // Index 0 is unused
388 assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
389 if (tag_at(index).is_klass()) {
390 // This class was resolved as a side effect of executing Java code
391 // during dump time. We need to restore it back to an UnresolvedClass,
392 // so that the proper class loading and initialization can happen
393 // at runtime.
394 CPKlassSlot kslot = klass_slot_at(index);
395 int resolved_klass_index = kslot.resolved_klass_index();
396 int name_index = kslot.name_index();
397 assert(tag_at(name_index).is_symbol(), "sanity");
398 resolved_klasses()->at_put(resolved_klass_index, NULL);
399 tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
400 assert(klass_name_at(index) == symbol_at(name_index), "sanity");
401 }
402 }
403 if (cache() != NULL) {
404 cache()->remove_unshareable_info();
405 }
406 }
407
cp_to_object_index(int cp_index)408 int ConstantPool::cp_to_object_index(int cp_index) {
409 // this is harder don't do this so much.
410 int i = reference_map()->find(cp_index);
411 // We might not find the index for jsr292 call.
412 return (i < 0) ? _no_index_sentinel : i;
413 }
414
string_at_put(int which,int obj_index,oop str)415 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
416 resolved_references()->obj_at_put(obj_index, str);
417 }
418
trace_class_resolution(const constantPoolHandle & this_cp,Klass * k)419 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
420 ResourceMark rm;
421 int line_number = -1;
422 const char * source_file = NULL;
423 if (JavaThread::current()->has_last_Java_frame()) {
424 // try to identify the method which called this function.
425 vframeStream vfst(JavaThread::current());
426 if (!vfst.at_end()) {
427 line_number = vfst.method()->line_number_from_bci(vfst.bci());
428 Symbol* s = vfst.method()->method_holder()->source_file_name();
429 if (s != NULL) {
430 source_file = s->as_C_string();
431 }
432 }
433 }
434 if (k != this_cp->pool_holder()) {
435 // only print something if the classes are different
436 if (source_file != NULL) {
437 log_debug(class, resolve)("%s %s %s:%d",
438 this_cp->pool_holder()->external_name(),
439 k->external_name(), source_file, line_number);
440 } else {
441 log_debug(class, resolve)("%s %s",
442 this_cp->pool_holder()->external_name(),
443 k->external_name());
444 }
445 }
446 }
447
klass_at_impl(const constantPoolHandle & this_cp,int which,bool save_resolution_error,TRAPS)448 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
449 bool save_resolution_error, TRAPS) {
450 assert(THREAD->is_Java_thread(), "must be a Java thread");
451
452 // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
453 // It is not safe to rely on the tag bit's here, since we don't have a lock, and
454 // the entry and tag is not updated atomicly.
455 CPKlassSlot kslot = this_cp->klass_slot_at(which);
456 int resolved_klass_index = kslot.resolved_klass_index();
457 int name_index = kslot.name_index();
458 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
459
460 Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
461 if (klass != NULL) {
462 return klass;
463 }
464
465 // This tag doesn't change back to unresolved class unless at a safepoint.
466 if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
467 // The original attempt to resolve this constant pool entry failed so find the
468 // class of the original error and throw another error of the same class
469 // (JVMS 5.4.3).
470 // If there is a detail message, pass that detail message to the error.
471 // The JVMS does not strictly require us to duplicate the same detail message,
472 // or any internal exception fields such as cause or stacktrace. But since the
473 // detail message is often a class name or other literal string, we will repeat it
474 // if we can find it in the symbol table.
475 throw_resolution_error(this_cp, which, CHECK_NULL);
476 ShouldNotReachHere();
477 }
478
479 Handle mirror_handle;
480 Symbol* name = this_cp->symbol_at(name_index);
481 Handle loader (THREAD, this_cp->pool_holder()->class_loader());
482 Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
483 Klass* k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
484 if (!HAS_PENDING_EXCEPTION) {
485 // preserve the resolved klass from unloading
486 mirror_handle = Handle(THREAD, k->java_mirror());
487 // Do access check for klasses
488 verify_constant_pool_resolve(this_cp, k, THREAD);
489 }
490
491 // Failed to resolve class. We must record the errors so that subsequent attempts
492 // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
493 if (HAS_PENDING_EXCEPTION) {
494 if (save_resolution_error) {
495 save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
496 // If CHECK_NULL above doesn't return the exception, that means that
497 // some other thread has beaten us and has resolved the class.
498 // To preserve old behavior, we return the resolved class.
499 klass = this_cp->resolved_klasses()->at(resolved_klass_index);
500 assert(klass != NULL, "must be resolved if exception was cleared");
501 return klass;
502 } else {
503 return NULL; // return the pending exception
504 }
505 }
506
507 // logging for class+resolve.
508 if (log_is_enabled(Debug, class, resolve)){
509 trace_class_resolution(this_cp, k);
510 }
511 Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
512 OrderAccess::release_store(adr, k);
513 // The interpreter assumes when the tag is stored, the klass is resolved
514 // and the Klass* stored in _resolved_klasses is non-NULL, so we need
515 // hardware store ordering here.
516 this_cp->release_tag_at_put(which, JVM_CONSTANT_Class);
517 return k;
518 }
519
520
521 // Does not update ConstantPool* - to avoid any exception throwing. Used
522 // by compiler and exception handling. Also used to avoid classloads for
523 // instanceof operations. Returns NULL if the class has not been loaded or
524 // if the verification of constant pool failed
klass_at_if_loaded(const constantPoolHandle & this_cp,int which)525 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
526 CPKlassSlot kslot = this_cp->klass_slot_at(which);
527 int resolved_klass_index = kslot.resolved_klass_index();
528 int name_index = kslot.name_index();
529 assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
530
531 Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
532 if (k != NULL) {
533 return k;
534 } else {
535 Thread *thread = Thread::current();
536 Symbol* name = this_cp->symbol_at(name_index);
537 oop loader = this_cp->pool_holder()->class_loader();
538 oop protection_domain = this_cp->pool_holder()->protection_domain();
539 Handle h_prot (thread, protection_domain);
540 Handle h_loader (thread, loader);
541 Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
542
543 if (k != NULL) {
544 // Make sure that resolving is legal
545 EXCEPTION_MARK;
546 // return NULL if verification fails
547 verify_constant_pool_resolve(this_cp, k, THREAD);
548 if (HAS_PENDING_EXCEPTION) {
549 CLEAR_PENDING_EXCEPTION;
550 return NULL;
551 }
552 return k;
553 } else {
554 return k;
555 }
556 }
557 }
558
method_at_if_loaded(const constantPoolHandle & cpool,int which)559 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
560 int which) {
561 if (cpool->cache() == NULL) return NULL; // nothing to load yet
562 int cache_index = decode_cpcache_index(which, true);
563 if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
564 // FIXME: should be an assert
565 log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
566 return NULL;
567 }
568 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
569 return e->method_if_resolved(cpool);
570 }
571
572
has_appendix_at_if_loaded(const constantPoolHandle & cpool,int which)573 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
574 if (cpool->cache() == NULL) return false; // nothing to load yet
575 int cache_index = decode_cpcache_index(which, true);
576 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
577 return e->has_appendix();
578 }
579
appendix_at_if_loaded(const constantPoolHandle & cpool,int which)580 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
581 if (cpool->cache() == NULL) return NULL; // nothing to load yet
582 int cache_index = decode_cpcache_index(which, true);
583 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
584 return e->appendix_if_resolved(cpool);
585 }
586
587
has_method_type_at_if_loaded(const constantPoolHandle & cpool,int which)588 bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
589 if (cpool->cache() == NULL) return false; // nothing to load yet
590 int cache_index = decode_cpcache_index(which, true);
591 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
592 return e->has_method_type();
593 }
594
method_type_at_if_loaded(const constantPoolHandle & cpool,int which)595 oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
596 if (cpool->cache() == NULL) return NULL; // nothing to load yet
597 int cache_index = decode_cpcache_index(which, true);
598 ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
599 return e->method_type_if_resolved(cpool);
600 }
601
602
impl_name_ref_at(int which,bool uncached)603 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
604 int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
605 return symbol_at(name_index);
606 }
607
608
impl_signature_ref_at(int which,bool uncached)609 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
610 int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
611 return symbol_at(signature_index);
612 }
613
impl_name_and_type_ref_index_at(int which,bool uncached)614 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
615 int i = which;
616 if (!uncached && cache() != NULL) {
617 if (ConstantPool::is_invokedynamic_index(which)) {
618 // Invokedynamic index is index into the constant pool cache
619 int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
620 pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
621 assert(tag_at(pool_index).is_name_and_type(), "");
622 return pool_index;
623 }
624 // change byte-ordering and go via cache
625 i = remap_instruction_operand_from_cache(which);
626 } else {
627 if (tag_at(which).is_invoke_dynamic() ||
628 tag_at(which).is_dynamic_constant() ||
629 tag_at(which).is_dynamic_constant_in_error()) {
630 int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
631 assert(tag_at(pool_index).is_name_and_type(), "");
632 return pool_index;
633 }
634 }
635 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
636 assert(!tag_at(i).is_invoke_dynamic() &&
637 !tag_at(i).is_dynamic_constant() &&
638 !tag_at(i).is_dynamic_constant_in_error(), "Must be handled above");
639 jint ref_index = *int_at_addr(i);
640 return extract_high_short_from_int(ref_index);
641 }
642
impl_tag_ref_at(int which,bool uncached)643 constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
644 int pool_index = which;
645 if (!uncached && cache() != NULL) {
646 if (ConstantPool::is_invokedynamic_index(which)) {
647 // Invokedynamic index is index into resolved_references
648 pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
649 } else {
650 // change byte-ordering and go via cache
651 pool_index = remap_instruction_operand_from_cache(which);
652 }
653 }
654 return tag_at(pool_index);
655 }
656
impl_klass_ref_index_at(int which,bool uncached)657 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
658 guarantee(!ConstantPool::is_invokedynamic_index(which),
659 "an invokedynamic instruction does not have a klass");
660 int i = which;
661 if (!uncached && cache() != NULL) {
662 // change byte-ordering and go via cache
663 i = remap_instruction_operand_from_cache(which);
664 }
665 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
666 jint ref_index = *int_at_addr(i);
667 return extract_low_short_from_int(ref_index);
668 }
669
670
671
remap_instruction_operand_from_cache(int operand)672 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
673 int cpc_index = operand;
674 DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
675 assert((int)(u2)cpc_index == cpc_index, "clean u2");
676 int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
677 return member_index;
678 }
679
680
verify_constant_pool_resolve(const constantPoolHandle & this_cp,Klass * k,TRAPS)681 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
682 if (!(k->is_instance_klass() || k->is_objArray_klass())) {
683 return; // short cut, typeArray klass is always accessible
684 }
685 Klass* holder = this_cp->pool_holder();
686 bool fold_type_to_class = true;
687 LinkResolver::check_klass_accessability(holder, k, fold_type_to_class, CHECK);
688 }
689
690
name_ref_index_at(int which_nt)691 int ConstantPool::name_ref_index_at(int which_nt) {
692 jint ref_index = name_and_type_at(which_nt);
693 return extract_low_short_from_int(ref_index);
694 }
695
696
signature_ref_index_at(int which_nt)697 int ConstantPool::signature_ref_index_at(int which_nt) {
698 jint ref_index = name_and_type_at(which_nt);
699 return extract_high_short_from_int(ref_index);
700 }
701
702
klass_ref_at(int which,TRAPS)703 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
704 return klass_at(klass_ref_index_at(which), THREAD);
705 }
706
klass_name_at(int which) const707 Symbol* ConstantPool::klass_name_at(int which) const {
708 return symbol_at(klass_slot_at(which).name_index());
709 }
710
klass_ref_at_noresolve(int which)711 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
712 jint ref_index = klass_ref_index_at(which);
713 return klass_at_noresolve(ref_index);
714 }
715
uncached_klass_ref_at_noresolve(int which)716 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
717 jint ref_index = uncached_klass_ref_index_at(which);
718 return klass_at_noresolve(ref_index);
719 }
720
string_at_noresolve(int which)721 char* ConstantPool::string_at_noresolve(int which) {
722 return unresolved_string_at(which)->as_C_string();
723 }
724
basic_type_for_signature_at(int which) const725 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
726 return FieldType::basic_type(symbol_at(which));
727 }
728
729
resolve_string_constants_impl(const constantPoolHandle & this_cp,TRAPS)730 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
731 for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
732 if (this_cp->tag_at(index).is_string()) {
733 this_cp->string_at(index, CHECK);
734 }
735 }
736 }
737
exception_message(const constantPoolHandle & this_cp,int which,constantTag tag,oop pending_exception)738 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
739 // Dig out the detailed message to reuse if possible
740 Symbol* message = java_lang_Throwable::detail_message(pending_exception);
741 if (message != NULL) {
742 return message;
743 }
744
745 // Return specific message for the tag
746 switch (tag.value()) {
747 case JVM_CONSTANT_UnresolvedClass:
748 // return the class name in the error message
749 message = this_cp->klass_name_at(which);
750 break;
751 case JVM_CONSTANT_MethodHandle:
752 // return the method handle name in the error message
753 message = this_cp->method_handle_name_ref_at(which);
754 break;
755 case JVM_CONSTANT_MethodType:
756 // return the method type signature in the error message
757 message = this_cp->method_type_signature_at(which);
758 break;
759 default:
760 ShouldNotReachHere();
761 }
762
763 return message;
764 }
765
throw_resolution_error(const constantPoolHandle & this_cp,int which,TRAPS)766 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
767 Symbol* message = NULL;
768 Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
769 assert(error != NULL, "checking");
770 CLEAR_PENDING_EXCEPTION;
771 if (message != NULL) {
772 ResourceMark rm;
773 THROW_MSG(error, message->as_C_string());
774 } else {
775 THROW(error);
776 }
777 }
778
779 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
780 // exception in the resolution error table, so that the same exception is thrown again.
save_and_throw_exception(const constantPoolHandle & this_cp,int which,constantTag tag,TRAPS)781 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
782 constantTag tag, TRAPS) {
783 Symbol* error = PENDING_EXCEPTION->klass()->name();
784
785 int error_tag = tag.error_value();
786
787 if (!PENDING_EXCEPTION->
788 is_a(SystemDictionary::LinkageError_klass())) {
789 // Just throw the exception and don't prevent these classes from
790 // being loaded due to virtual machine errors like StackOverflow
791 // and OutOfMemoryError, etc, or if the thread was hit by stop()
792 // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
793 } else if (this_cp->tag_at(which).value() != error_tag) {
794 Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
795 SystemDictionary::add_resolution_error(this_cp, which, error, message);
796 // CAS in the tag. If a thread beat us to registering this error that's fine.
797 // If another thread resolved the reference, this is a race condition. This
798 // thread may have had a security manager or something temporary.
799 // This doesn't deterministically get an error. So why do we save this?
800 // We save this because jvmti can add classes to the bootclass path after
801 // this error, so it needs to get the same error if the error is first.
802 jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
803 (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
804 if (old_tag != error_tag && old_tag != tag.value()) {
805 // MethodHandles and MethodType doesn't change to resolved version.
806 assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
807 // Forget the exception and use the resolved class.
808 CLEAR_PENDING_EXCEPTION;
809 }
810 } else {
811 // some other thread put this in error state
812 throw_resolution_error(this_cp, which, CHECK);
813 }
814 }
815
constant_tag_at(int which)816 constantTag ConstantPool::constant_tag_at(int which) {
817 constantTag tag = tag_at(which);
818 if (tag.is_dynamic_constant() ||
819 tag.is_dynamic_constant_in_error()) {
820 BasicType bt = basic_type_for_constant_at(which);
821 // dynamic constant could return an array, treat as object
822 return constantTag::ofBasicType(is_reference_type(bt) ? T_OBJECT : bt);
823 }
824 return tag;
825 }
826
basic_type_for_constant_at(int which)827 BasicType ConstantPool::basic_type_for_constant_at(int which) {
828 constantTag tag = tag_at(which);
829 if (tag.is_dynamic_constant() ||
830 tag.is_dynamic_constant_in_error()) {
831 // have to look at the signature for this one
832 Symbol* constant_type = uncached_signature_ref_at(which);
833 return FieldType::basic_type(constant_type);
834 }
835 return tag.basic_type();
836 }
837
838 // Called to resolve constants in the constant pool and return an oop.
839 // Some constant pool entries cache their resolved oop. This is also
840 // called to create oops from constants to use in arguments for invokedynamic
resolve_constant_at_impl(const constantPoolHandle & this_cp,int index,int cache_index,bool * status_return,TRAPS)841 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
842 int index, int cache_index,
843 bool* status_return, TRAPS) {
844 oop result_oop = NULL;
845 Handle throw_exception;
846
847 if (cache_index == _possible_index_sentinel) {
848 // It is possible that this constant is one which is cached in the objects.
849 // We'll do a linear search. This should be OK because this usage is rare.
850 // FIXME: If bootstrap specifiers stress this code, consider putting in
851 // a reverse index. Binary search over a short array should do it.
852 assert(index > 0, "valid index");
853 cache_index = this_cp->cp_to_object_index(index);
854 }
855 assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
856 assert(index == _no_index_sentinel || index >= 0, "");
857
858 if (cache_index >= 0) {
859 result_oop = this_cp->resolved_references()->obj_at(cache_index);
860 if (result_oop != NULL) {
861 if (oopDesc::equals(result_oop, Universe::the_null_sentinel())) {
862 DEBUG_ONLY(int temp_index = (index >= 0 ? index : this_cp->object_to_cp_index(cache_index)));
863 assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
864 result_oop = NULL;
865 }
866 if (status_return != NULL) (*status_return) = true;
867 return result_oop;
868 // That was easy...
869 }
870 index = this_cp->object_to_cp_index(cache_index);
871 }
872
873 jvalue prim_value; // temp used only in a few cases below
874
875 constantTag tag = this_cp->tag_at(index);
876
877 if (status_return != NULL) {
878 // don't trigger resolution if the constant might need it
879 switch (tag.value()) {
880 case JVM_CONSTANT_Class:
881 {
882 CPKlassSlot kslot = this_cp->klass_slot_at(index);
883 int resolved_klass_index = kslot.resolved_klass_index();
884 if (this_cp->resolved_klasses()->at(resolved_klass_index) == NULL) {
885 (*status_return) = false;
886 return NULL;
887 }
888 // the klass is waiting in the CP; go get it
889 break;
890 }
891 case JVM_CONSTANT_String:
892 case JVM_CONSTANT_Integer:
893 case JVM_CONSTANT_Float:
894 case JVM_CONSTANT_Long:
895 case JVM_CONSTANT_Double:
896 // these guys trigger OOM at worst
897 break;
898 default:
899 (*status_return) = false;
900 return NULL;
901 }
902 // from now on there is either success or an OOME
903 (*status_return) = true;
904 }
905
906 switch (tag.value()) {
907
908 case JVM_CONSTANT_UnresolvedClass:
909 case JVM_CONSTANT_UnresolvedClassInError:
910 case JVM_CONSTANT_Class:
911 {
912 assert(cache_index == _no_index_sentinel, "should not have been set");
913 Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
914 // ldc wants the java mirror.
915 result_oop = resolved->java_mirror();
916 break;
917 }
918
919 case JVM_CONSTANT_Dynamic:
920 {
921 Klass* current_klass = this_cp->pool_holder();
922 Symbol* constant_name = this_cp->uncached_name_ref_at(index);
923 Symbol* constant_type = this_cp->uncached_signature_ref_at(index);
924
925 // The initial step in resolving an unresolved symbolic reference to a
926 // dynamically-computed constant is to resolve the symbolic reference to a
927 // method handle which will be the bootstrap method for the dynamically-computed
928 // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
929 // method fails, then a MethodHandleInError is stored at the corresponding
930 // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
931 // set a DynamicConstantInError here since any subsequent use of this
932 // bootstrap method will encounter the resolution of MethodHandleInError.
933 oop bsm_info = this_cp->resolve_bootstrap_specifier_at(index, THREAD);
934 Exceptions::wrap_dynamic_exception(CHECK_NULL);
935 assert(bsm_info != NULL, "");
936 // FIXME: Cache this once per BootstrapMethods entry, not once per CONSTANT_Dynamic.
937 Handle bootstrap_specifier = Handle(THREAD, bsm_info);
938
939 // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
940 Handle value = SystemDictionary::link_dynamic_constant(current_klass,
941 index,
942 bootstrap_specifier,
943 constant_name,
944 constant_type,
945 THREAD);
946 result_oop = value();
947 Exceptions::wrap_dynamic_exception(THREAD);
948 if (HAS_PENDING_EXCEPTION) {
949 // Resolution failure of the dynamically-computed constant, save_and_throw_exception
950 // will check for a LinkageError and store a DynamicConstantInError.
951 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
952 }
953 BasicType type = FieldType::basic_type(constant_type);
954 if (!is_reference_type(type)) {
955 // Make sure the primitive value is properly boxed.
956 // This is a JDK responsibility.
957 const char* fail = NULL;
958 if (result_oop == NULL) {
959 fail = "null result instead of box";
960 } else if (!is_java_primitive(type)) {
961 // FIXME: support value types via unboxing
962 fail = "can only handle references and primitives";
963 } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
964 fail = "primitive is not properly boxed";
965 }
966 if (fail != NULL) {
967 // Since this exception is not a LinkageError, throw exception
968 // but do not save a DynamicInError resolution result.
969 // See section 5.4.3 of the VM spec.
970 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
971 }
972 }
973 break;
974 }
975
976 case JVM_CONSTANT_String:
977 assert(cache_index != _no_index_sentinel, "should have been set");
978 if (this_cp->is_pseudo_string_at(index)) {
979 result_oop = this_cp->pseudo_string_at(index, cache_index);
980 break;
981 }
982 result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
983 break;
984
985 case JVM_CONSTANT_DynamicInError:
986 case JVM_CONSTANT_MethodHandleInError:
987 case JVM_CONSTANT_MethodTypeInError:
988 {
989 throw_resolution_error(this_cp, index, CHECK_NULL);
990 break;
991 }
992
993 case JVM_CONSTANT_MethodHandle:
994 {
995 int ref_kind = this_cp->method_handle_ref_kind_at(index);
996 int callee_index = this_cp->method_handle_klass_index_at(index);
997 Symbol* name = this_cp->method_handle_name_ref_at(index);
998 Symbol* signature = this_cp->method_handle_signature_ref_at(index);
999 constantTag m_tag = this_cp->tag_at(this_cp->method_handle_index_at(index));
1000 { ResourceMark rm(THREAD);
1001 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1002 ref_kind, index, this_cp->method_handle_index_at(index),
1003 callee_index, name->as_C_string(), signature->as_C_string());
1004 }
1005
1006 Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
1007
1008 // Check constant pool method consistency
1009 if ((callee->is_interface() && m_tag.is_method()) ||
1010 ((!callee->is_interface() && m_tag.is_interface_method()))) {
1011 ResourceMark rm(THREAD);
1012 char buf[400];
1013 jio_snprintf(buf, sizeof(buf),
1014 "Inconsistent constant pool data in classfile for class %s. "
1015 "Method %s%s at index %d is %s and should be %s",
1016 callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
1017 callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1018 callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1019 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
1020 }
1021
1022 Klass* klass = this_cp->pool_holder();
1023 Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1024 callee, name, signature,
1025 THREAD);
1026 result_oop = value();
1027 if (HAS_PENDING_EXCEPTION) {
1028 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
1029 }
1030 break;
1031 }
1032
1033 case JVM_CONSTANT_MethodType:
1034 {
1035 Symbol* signature = this_cp->method_type_signature_at(index);
1036 { ResourceMark rm(THREAD);
1037 log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1038 index, this_cp->method_type_index_at(index),
1039 signature->as_C_string());
1040 }
1041 Klass* klass = this_cp->pool_holder();
1042 Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1043 result_oop = value();
1044 if (HAS_PENDING_EXCEPTION) {
1045 save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
1046 }
1047 break;
1048 }
1049
1050 case JVM_CONSTANT_Integer:
1051 assert(cache_index == _no_index_sentinel, "should not have been set");
1052 prim_value.i = this_cp->int_at(index);
1053 result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1054 break;
1055
1056 case JVM_CONSTANT_Float:
1057 assert(cache_index == _no_index_sentinel, "should not have been set");
1058 prim_value.f = this_cp->float_at(index);
1059 result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1060 break;
1061
1062 case JVM_CONSTANT_Long:
1063 assert(cache_index == _no_index_sentinel, "should not have been set");
1064 prim_value.j = this_cp->long_at(index);
1065 result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1066 break;
1067
1068 case JVM_CONSTANT_Double:
1069 assert(cache_index == _no_index_sentinel, "should not have been set");
1070 prim_value.d = this_cp->double_at(index);
1071 result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1072 break;
1073
1074 default:
1075 DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
1076 this_cp(), index, cache_index, tag.value()));
1077 assert(false, "unexpected constant tag");
1078 break;
1079 }
1080
1081 if (cache_index >= 0) {
1082 // Benign race condition: resolved_references may already be filled in.
1083 // The important thing here is that all threads pick up the same result.
1084 // It doesn't matter which racing thread wins, as long as only one
1085 // result is used by all threads, and all future queries.
1086 oop new_result = (result_oop == NULL ? Universe::the_null_sentinel() : result_oop);
1087 oop old_result = this_cp->resolved_references()
1088 ->atomic_compare_exchange_oop(cache_index, new_result, NULL);
1089 if (old_result == NULL) {
1090 return result_oop; // was installed
1091 } else {
1092 // Return the winning thread's result. This can be different than
1093 // the result here for MethodHandles.
1094 if (oopDesc::equals(old_result, Universe::the_null_sentinel()))
1095 old_result = NULL;
1096 return old_result;
1097 }
1098 } else {
1099 assert(!oopDesc::equals(result_oop, Universe::the_null_sentinel()), "");
1100 return result_oop;
1101 }
1102 }
1103
uncached_string_at(int which,TRAPS)1104 oop ConstantPool::uncached_string_at(int which, TRAPS) {
1105 Symbol* sym = unresolved_string_at(which);
1106 oop str = StringTable::intern(sym, CHECK_(NULL));
1107 assert(java_lang_String::is_instance(str), "must be string");
1108 return str;
1109 }
1110
1111
resolve_bootstrap_specifier_at_impl(const constantPoolHandle & this_cp,int index,TRAPS)1112 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
1113 assert((this_cp->tag_at(index).is_invoke_dynamic() ||
1114 this_cp->tag_at(index).is_dynamic_constant()), "Corrupted constant pool");
1115 Handle bsm;
1116 int argc;
1117 {
1118 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&mtype], plus optional arguments
1119 // JVM_CONSTANT_Dynamic is an ordered pair of [bootm, name&ftype], plus optional arguments
1120 // In both cases, the bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
1121 // It is accompanied by the optional arguments.
1122 int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
1123 oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
1124 if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
1125 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
1126 }
1127
1128 // Extract the optional static arguments.
1129 argc = this_cp->invoke_dynamic_argument_count_at(index);
1130
1131 // if there are no static arguments, return the bsm by itself:
1132 if (argc == 0 && UseBootstrapCallInfo < 2) return bsm_oop;
1133
1134 bsm = Handle(THREAD, bsm_oop);
1135 }
1136
1137 // We are going to return an ordered pair of {bsm, info}, using a 2-array.
1138 objArrayHandle info;
1139 {
1140 objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 2, CHECK_NULL);
1141 info = objArrayHandle(THREAD, info_oop);
1142 }
1143
1144 info->obj_at_put(0, bsm());
1145
1146 bool use_BSCI;
1147 switch (UseBootstrapCallInfo) {
1148 default: use_BSCI = true; break; // stress mode
1149 case 0: use_BSCI = false; break; // stress mode
1150 case 1: // normal mode
1151 // If we were to support an alternative mode of BSM invocation,
1152 // we'd convert to pull mode here if the BSM could be a candidate
1153 // for that alternative mode. We can't easily test for things
1154 // like varargs here, but we can get away with approximate testing,
1155 // since the JDK runtime will make up the difference either way.
1156 // For now, exercise the pull-mode path if the BSM is of arity 2,
1157 // or if there is a potential condy loop (see below).
1158 oop mt_oop = java_lang_invoke_MethodHandle::type(bsm());
1159 use_BSCI = (java_lang_invoke_MethodType::ptype_count(mt_oop) == 2);
1160 break;
1161 }
1162
1163 // Here's a reason to use BSCI even if it wasn't requested:
1164 // If a condy uses a condy argument, we want to avoid infinite
1165 // recursion (condy loops) in the C code. It's OK in Java,
1166 // because Java has stack overflow checking, so we punt
1167 // potentially cyclic cases from C to Java.
1168 if (!use_BSCI && this_cp->tag_at(index).is_dynamic_constant()) {
1169 bool found_unresolved_condy = false;
1170 for (int i = 0; i < argc; i++) {
1171 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1172 if (this_cp->tag_at(arg_index).is_dynamic_constant()) {
1173 // potential recursion point condy -> condy
1174 bool found_it = false;
1175 this_cp->find_cached_constant_at(arg_index, found_it, CHECK_NULL);
1176 if (!found_it) { found_unresolved_condy = true; break; }
1177 }
1178 }
1179 if (found_unresolved_condy)
1180 use_BSCI = true;
1181 }
1182
1183 const int SMALL_ARITY = 5;
1184 if (use_BSCI && argc <= SMALL_ARITY && UseBootstrapCallInfo <= 2) {
1185 // If there are only a few arguments, and none of them need linking,
1186 // push them, instead of asking the JDK runtime to turn around and
1187 // pull them, saving a JVM/JDK transition in some simple cases.
1188 bool all_resolved = true;
1189 for (int i = 0; i < argc; i++) {
1190 bool found_it = false;
1191 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1192 this_cp->find_cached_constant_at(arg_index, found_it, CHECK_NULL);
1193 if (!found_it) { all_resolved = false; break; }
1194 }
1195 if (all_resolved)
1196 use_BSCI = false;
1197 }
1198
1199 if (!use_BSCI) {
1200 // return {bsm, {arg...}}; resolution of arguments is done immediately, before JDK code is called
1201 objArrayOop args_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), argc, CHECK_NULL);
1202 info->obj_at_put(1, args_oop); // may overwrite with args[0] below
1203 objArrayHandle args(THREAD, args_oop);
1204 copy_bootstrap_arguments_at_impl(this_cp, index, 0, argc, args, 0, true, Handle(), CHECK_NULL);
1205 if (argc == 1) {
1206 // try to discard the singleton array
1207 oop arg_oop = args->obj_at(0);
1208 if (arg_oop != NULL && !arg_oop->is_array()) {
1209 // JVM treats arrays and nulls specially in this position,
1210 // but other things are just single arguments
1211 info->obj_at_put(1, arg_oop);
1212 }
1213 }
1214 } else {
1215 // return {bsm, {arg_count, pool_index}}; JDK code must pull the arguments as needed
1216 typeArrayOop ints_oop = oopFactory::new_typeArray(T_INT, 2, CHECK_NULL);
1217 ints_oop->int_at_put(0, argc);
1218 ints_oop->int_at_put(1, index);
1219 info->obj_at_put(1, ints_oop);
1220 }
1221 return info();
1222 }
1223
copy_bootstrap_arguments_at_impl(const constantPoolHandle & this_cp,int index,int start_arg,int end_arg,objArrayHandle info,int pos,bool must_resolve,Handle if_not_available,TRAPS)1224 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int index,
1225 int start_arg, int end_arg,
1226 objArrayHandle info, int pos,
1227 bool must_resolve, Handle if_not_available,
1228 TRAPS) {
1229 int argc;
1230 int limit = pos + end_arg - start_arg;
1231 // checks: index in range [0..this_cp->length),
1232 // tag at index, start..end in range [0..argc],
1233 // info array non-null, pos..limit in [0..info.length]
1234 if ((0 >= index || index >= this_cp->length()) ||
1235 !(this_cp->tag_at(index).is_invoke_dynamic() ||
1236 this_cp->tag_at(index).is_dynamic_constant()) ||
1237 (0 > start_arg || start_arg > end_arg) ||
1238 (end_arg > (argc = this_cp->invoke_dynamic_argument_count_at(index))) ||
1239 (0 > pos || pos > limit) ||
1240 (info.is_null() || limit > info->length())) {
1241 // An index or something else went wrong; throw an error.
1242 // Since this is an internal API, we don't expect this,
1243 // so we don't bother to craft a nice message.
1244 THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1245 }
1246 // now we can loop safely
1247 int info_i = pos;
1248 for (int i = start_arg; i < end_arg; i++) {
1249 int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
1250 oop arg_oop;
1251 if (must_resolve) {
1252 arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1253 } else {
1254 bool found_it = false;
1255 arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1256 if (!found_it) arg_oop = if_not_available();
1257 }
1258 info->obj_at_put(info_i++, arg_oop);
1259 }
1260 }
1261
string_at_impl(const constantPoolHandle & this_cp,int which,int obj_index,TRAPS)1262 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
1263 // If the string has already been interned, this entry will be non-null
1264 oop str = this_cp->resolved_references()->obj_at(obj_index);
1265 assert(!oopDesc::equals(str, Universe::the_null_sentinel()), "");
1266 if (str != NULL) return str;
1267 Symbol* sym = this_cp->unresolved_string_at(which);
1268 str = StringTable::intern(sym, CHECK_(NULL));
1269 this_cp->string_at_put(which, obj_index, str);
1270 assert(java_lang_String::is_instance(str), "must be string");
1271 return str;
1272 }
1273
1274
klass_name_at_matches(const InstanceKlass * k,int which)1275 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
1276 // Names are interned, so we can compare Symbol*s directly
1277 Symbol* cp_name = klass_name_at(which);
1278 return (cp_name == k->name());
1279 }
1280
1281
1282 // Iterate over symbols and decrement ones which are Symbol*s
1283 // This is done during GC.
1284 // Only decrement the UTF8 symbols. Strings point to
1285 // these symbols but didn't increment the reference count.
unreference_symbols()1286 void ConstantPool::unreference_symbols() {
1287 for (int index = 1; index < length(); index++) { // Index 0 is unused
1288 constantTag tag = tag_at(index);
1289 if (tag.is_symbol()) {
1290 symbol_at(index)->decrement_refcount();
1291 }
1292 }
1293 }
1294
1295
1296 // Compare this constant pool's entry at index1 to the constant pool
1297 // cp2's entry at index2.
compare_entry_to(int index1,const constantPoolHandle & cp2,int index2,TRAPS)1298 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1299 int index2, TRAPS) {
1300
1301 // The error tags are equivalent to non-error tags when comparing
1302 jbyte t1 = tag_at(index1).non_error_value();
1303 jbyte t2 = cp2->tag_at(index2).non_error_value();
1304
1305 if (t1 != t2) {
1306 // Not the same entry type so there is nothing else to check. Note
1307 // that this style of checking will consider resolved/unresolved
1308 // class pairs as different.
1309 // From the ConstantPool* API point of view, this is correct
1310 // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1311 // plays out in the context of ConstantPool* merging.
1312 return false;
1313 }
1314
1315 switch (t1) {
1316 case JVM_CONSTANT_Class:
1317 {
1318 Klass* k1 = klass_at(index1, CHECK_false);
1319 Klass* k2 = cp2->klass_at(index2, CHECK_false);
1320 if (k1 == k2) {
1321 return true;
1322 }
1323 } break;
1324
1325 case JVM_CONSTANT_ClassIndex:
1326 {
1327 int recur1 = klass_index_at(index1);
1328 int recur2 = cp2->klass_index_at(index2);
1329 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1330 if (match) {
1331 return true;
1332 }
1333 } break;
1334
1335 case JVM_CONSTANT_Double:
1336 {
1337 jdouble d1 = double_at(index1);
1338 jdouble d2 = cp2->double_at(index2);
1339 if (d1 == d2) {
1340 return true;
1341 }
1342 } break;
1343
1344 case JVM_CONSTANT_Fieldref:
1345 case JVM_CONSTANT_InterfaceMethodref:
1346 case JVM_CONSTANT_Methodref:
1347 {
1348 int recur1 = uncached_klass_ref_index_at(index1);
1349 int recur2 = cp2->uncached_klass_ref_index_at(index2);
1350 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1351 if (match) {
1352 recur1 = uncached_name_and_type_ref_index_at(index1);
1353 recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1354 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1355 if (match) {
1356 return true;
1357 }
1358 }
1359 } break;
1360
1361 case JVM_CONSTANT_Float:
1362 {
1363 jfloat f1 = float_at(index1);
1364 jfloat f2 = cp2->float_at(index2);
1365 if (f1 == f2) {
1366 return true;
1367 }
1368 } break;
1369
1370 case JVM_CONSTANT_Integer:
1371 {
1372 jint i1 = int_at(index1);
1373 jint i2 = cp2->int_at(index2);
1374 if (i1 == i2) {
1375 return true;
1376 }
1377 } break;
1378
1379 case JVM_CONSTANT_Long:
1380 {
1381 jlong l1 = long_at(index1);
1382 jlong l2 = cp2->long_at(index2);
1383 if (l1 == l2) {
1384 return true;
1385 }
1386 } break;
1387
1388 case JVM_CONSTANT_NameAndType:
1389 {
1390 int recur1 = name_ref_index_at(index1);
1391 int recur2 = cp2->name_ref_index_at(index2);
1392 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1393 if (match) {
1394 recur1 = signature_ref_index_at(index1);
1395 recur2 = cp2->signature_ref_index_at(index2);
1396 match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1397 if (match) {
1398 return true;
1399 }
1400 }
1401 } break;
1402
1403 case JVM_CONSTANT_StringIndex:
1404 {
1405 int recur1 = string_index_at(index1);
1406 int recur2 = cp2->string_index_at(index2);
1407 bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1408 if (match) {
1409 return true;
1410 }
1411 } break;
1412
1413 case JVM_CONSTANT_UnresolvedClass:
1414 {
1415 Symbol* k1 = klass_name_at(index1);
1416 Symbol* k2 = cp2->klass_name_at(index2);
1417 if (k1 == k2) {
1418 return true;
1419 }
1420 } break;
1421
1422 case JVM_CONSTANT_MethodType:
1423 {
1424 int k1 = method_type_index_at(index1);
1425 int k2 = cp2->method_type_index_at(index2);
1426 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1427 if (match) {
1428 return true;
1429 }
1430 } break;
1431
1432 case JVM_CONSTANT_MethodHandle:
1433 {
1434 int k1 = method_handle_ref_kind_at(index1);
1435 int k2 = cp2->method_handle_ref_kind_at(index2);
1436 if (k1 == k2) {
1437 int i1 = method_handle_index_at(index1);
1438 int i2 = cp2->method_handle_index_at(index2);
1439 bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1440 if (match) {
1441 return true;
1442 }
1443 }
1444 } break;
1445
1446 case JVM_CONSTANT_Dynamic:
1447 {
1448 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1449 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1450 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1451 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1452 // separate statements and variables because CHECK_false is used
1453 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1454 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1455 return (match_entry && match_operand);
1456 } break;
1457
1458 case JVM_CONSTANT_InvokeDynamic:
1459 {
1460 int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
1461 int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
1462 int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
1463 int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
1464 // separate statements and variables because CHECK_false is used
1465 bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1466 bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1467 return (match_entry && match_operand);
1468 } break;
1469
1470 case JVM_CONSTANT_String:
1471 {
1472 Symbol* s1 = unresolved_string_at(index1);
1473 Symbol* s2 = cp2->unresolved_string_at(index2);
1474 if (s1 == s2) {
1475 return true;
1476 }
1477 } break;
1478
1479 case JVM_CONSTANT_Utf8:
1480 {
1481 Symbol* s1 = symbol_at(index1);
1482 Symbol* s2 = cp2->symbol_at(index2);
1483 if (s1 == s2) {
1484 return true;
1485 }
1486 } break;
1487
1488 // Invalid is used as the tag for the second constant pool entry
1489 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1490 // not be seen by itself.
1491 case JVM_CONSTANT_Invalid: // fall through
1492
1493 default:
1494 ShouldNotReachHere();
1495 break;
1496 }
1497
1498 return false;
1499 } // end compare_entry_to()
1500
1501
1502 // Resize the operands array with delta_len and delta_size.
1503 // Used in RedefineClasses for CP merge.
resize_operands(int delta_len,int delta_size,TRAPS)1504 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1505 int old_len = operand_array_length(operands());
1506 int new_len = old_len + delta_len;
1507 int min_len = (delta_len > 0) ? old_len : new_len;
1508
1509 int old_size = operands()->length();
1510 int new_size = old_size + delta_size;
1511 int min_size = (delta_size > 0) ? old_size : new_size;
1512
1513 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1514 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1515
1516 // Set index in the resized array for existing elements only
1517 for (int idx = 0; idx < min_len; idx++) {
1518 int offset = operand_offset_at(idx); // offset in original array
1519 operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1520 }
1521 // Copy the bootstrap specifiers only
1522 Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1523 new_ops->adr_at(2*new_len),
1524 (min_size - 2*min_len) * sizeof(u2));
1525 // Explicitly deallocate old operands array.
1526 // Note, it is not needed for 7u backport.
1527 if ( operands() != NULL) { // the safety check
1528 MetadataFactory::free_array<u2>(loader_data, operands());
1529 }
1530 set_operands(new_ops);
1531 } // end resize_operands()
1532
1533
1534 // Extend the operands array with the length and size of the ext_cp operands.
1535 // Used in RedefineClasses for CP merge.
extend_operands(const constantPoolHandle & ext_cp,TRAPS)1536 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1537 int delta_len = operand_array_length(ext_cp->operands());
1538 if (delta_len == 0) {
1539 return; // nothing to do
1540 }
1541 int delta_size = ext_cp->operands()->length();
1542
1543 assert(delta_len > 0 && delta_size > 0, "extended operands array must be bigger");
1544
1545 if (operand_array_length(operands()) == 0) {
1546 ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1547 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1548 // The first element index defines the offset of second part
1549 operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1550 set_operands(new_ops);
1551 } else {
1552 resize_operands(delta_len, delta_size, CHECK);
1553 }
1554
1555 } // end extend_operands()
1556
1557
1558 // Shrink the operands array to a smaller array with new_len length.
1559 // Used in RedefineClasses for CP merge.
shrink_operands(int new_len,TRAPS)1560 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1561 int old_len = operand_array_length(operands());
1562 if (new_len == old_len) {
1563 return; // nothing to do
1564 }
1565 assert(new_len < old_len, "shrunken operands array must be smaller");
1566
1567 int free_base = operand_next_offset_at(new_len - 1);
1568 int delta_len = new_len - old_len;
1569 int delta_size = 2*delta_len + free_base - operands()->length();
1570
1571 resize_operands(delta_len, delta_size, CHECK);
1572
1573 } // end shrink_operands()
1574
1575
copy_operands(const constantPoolHandle & from_cp,const constantPoolHandle & to_cp,TRAPS)1576 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1577 const constantPoolHandle& to_cp,
1578 TRAPS) {
1579
1580 int from_oplen = operand_array_length(from_cp->operands());
1581 int old_oplen = operand_array_length(to_cp->operands());
1582 if (from_oplen != 0) {
1583 ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1584 // append my operands to the target's operands array
1585 if (old_oplen == 0) {
1586 // Can't just reuse from_cp's operand list because of deallocation issues
1587 int len = from_cp->operands()->length();
1588 Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1589 Copy::conjoint_memory_atomic(
1590 from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1591 to_cp->set_operands(new_ops);
1592 } else {
1593 int old_len = to_cp->operands()->length();
1594 int from_len = from_cp->operands()->length();
1595 int old_off = old_oplen * sizeof(u2);
1596 int from_off = from_oplen * sizeof(u2);
1597 // Use the metaspace for the destination constant pool
1598 Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1599 int fillp = 0, len = 0;
1600 // first part of dest
1601 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1602 new_operands->adr_at(fillp),
1603 (len = old_off) * sizeof(u2));
1604 fillp += len;
1605 // first part of src
1606 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1607 new_operands->adr_at(fillp),
1608 (len = from_off) * sizeof(u2));
1609 fillp += len;
1610 // second part of dest
1611 Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1612 new_operands->adr_at(fillp),
1613 (len = old_len - old_off) * sizeof(u2));
1614 fillp += len;
1615 // second part of src
1616 Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1617 new_operands->adr_at(fillp),
1618 (len = from_len - from_off) * sizeof(u2));
1619 fillp += len;
1620 assert(fillp == new_operands->length(), "");
1621
1622 // Adjust indexes in the first part of the copied operands array.
1623 for (int j = 0; j < from_oplen; j++) {
1624 int offset = operand_offset_at(new_operands, old_oplen + j);
1625 assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1626 offset += old_len; // every new tuple is preceded by old_len extra u2's
1627 operand_offset_at_put(new_operands, old_oplen + j, offset);
1628 }
1629
1630 // replace target operands array with combined array
1631 to_cp->set_operands(new_operands);
1632 }
1633 }
1634 } // end copy_operands()
1635
1636
1637 // Copy this constant pool's entries at start_i to end_i (inclusive)
1638 // to the constant pool to_cp's entries starting at to_i. A total of
1639 // (end_i - start_i) + 1 entries are copied.
copy_cp_to_impl(const constantPoolHandle & from_cp,int start_i,int end_i,const constantPoolHandle & to_cp,int to_i,TRAPS)1640 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1641 const constantPoolHandle& to_cp, int to_i, TRAPS) {
1642
1643
1644 int dest_i = to_i; // leave original alone for debug purposes
1645
1646 for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1647 copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1648
1649 switch (from_cp->tag_at(src_i).value()) {
1650 case JVM_CONSTANT_Double:
1651 case JVM_CONSTANT_Long:
1652 // double and long take two constant pool entries
1653 src_i += 2;
1654 dest_i += 2;
1655 break;
1656
1657 default:
1658 // all others take one constant pool entry
1659 src_i++;
1660 dest_i++;
1661 break;
1662 }
1663 }
1664 copy_operands(from_cp, to_cp, CHECK);
1665
1666 } // end copy_cp_to_impl()
1667
1668
1669 // Copy this constant pool's entry at from_i to the constant pool
1670 // to_cp's entry at to_i.
copy_entry_to(const constantPoolHandle & from_cp,int from_i,const constantPoolHandle & to_cp,int to_i,TRAPS)1671 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1672 const constantPoolHandle& to_cp, int to_i,
1673 TRAPS) {
1674
1675 int tag = from_cp->tag_at(from_i).value();
1676 switch (tag) {
1677 case JVM_CONSTANT_ClassIndex:
1678 {
1679 jint ki = from_cp->klass_index_at(from_i);
1680 to_cp->klass_index_at_put(to_i, ki);
1681 } break;
1682
1683 case JVM_CONSTANT_Double:
1684 {
1685 jdouble d = from_cp->double_at(from_i);
1686 to_cp->double_at_put(to_i, d);
1687 // double takes two constant pool entries so init second entry's tag
1688 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1689 } break;
1690
1691 case JVM_CONSTANT_Fieldref:
1692 {
1693 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1694 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1695 to_cp->field_at_put(to_i, class_index, name_and_type_index);
1696 } break;
1697
1698 case JVM_CONSTANT_Float:
1699 {
1700 jfloat f = from_cp->float_at(from_i);
1701 to_cp->float_at_put(to_i, f);
1702 } break;
1703
1704 case JVM_CONSTANT_Integer:
1705 {
1706 jint i = from_cp->int_at(from_i);
1707 to_cp->int_at_put(to_i, i);
1708 } break;
1709
1710 case JVM_CONSTANT_InterfaceMethodref:
1711 {
1712 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1713 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1714 to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1715 } break;
1716
1717 case JVM_CONSTANT_Long:
1718 {
1719 jlong l = from_cp->long_at(from_i);
1720 to_cp->long_at_put(to_i, l);
1721 // long takes two constant pool entries so init second entry's tag
1722 to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1723 } break;
1724
1725 case JVM_CONSTANT_Methodref:
1726 {
1727 int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1728 int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1729 to_cp->method_at_put(to_i, class_index, name_and_type_index);
1730 } break;
1731
1732 case JVM_CONSTANT_NameAndType:
1733 {
1734 int name_ref_index = from_cp->name_ref_index_at(from_i);
1735 int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1736 to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1737 } break;
1738
1739 case JVM_CONSTANT_StringIndex:
1740 {
1741 jint si = from_cp->string_index_at(from_i);
1742 to_cp->string_index_at_put(to_i, si);
1743 } break;
1744
1745 case JVM_CONSTANT_Class:
1746 case JVM_CONSTANT_UnresolvedClass:
1747 case JVM_CONSTANT_UnresolvedClassInError:
1748 {
1749 // Revert to JVM_CONSTANT_ClassIndex
1750 int name_index = from_cp->klass_slot_at(from_i).name_index();
1751 assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1752 to_cp->klass_index_at_put(to_i, name_index);
1753 } break;
1754
1755 case JVM_CONSTANT_String:
1756 {
1757 Symbol* s = from_cp->unresolved_string_at(from_i);
1758 to_cp->unresolved_string_at_put(to_i, s);
1759 } break;
1760
1761 case JVM_CONSTANT_Utf8:
1762 {
1763 Symbol* s = from_cp->symbol_at(from_i);
1764 // Need to increase refcount, the old one will be thrown away and deferenced
1765 s->increment_refcount();
1766 to_cp->symbol_at_put(to_i, s);
1767 } break;
1768
1769 case JVM_CONSTANT_MethodType:
1770 case JVM_CONSTANT_MethodTypeInError:
1771 {
1772 jint k = from_cp->method_type_index_at(from_i);
1773 to_cp->method_type_index_at_put(to_i, k);
1774 } break;
1775
1776 case JVM_CONSTANT_MethodHandle:
1777 case JVM_CONSTANT_MethodHandleInError:
1778 {
1779 int k1 = from_cp->method_handle_ref_kind_at(from_i);
1780 int k2 = from_cp->method_handle_index_at(from_i);
1781 to_cp->method_handle_index_at_put(to_i, k1, k2);
1782 } break;
1783
1784 case JVM_CONSTANT_Dynamic:
1785 case JVM_CONSTANT_DynamicInError:
1786 {
1787 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1788 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1789 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1790 to_cp->dynamic_constant_at_put(to_i, k1, k2);
1791 } break;
1792
1793 case JVM_CONSTANT_InvokeDynamic:
1794 {
1795 int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1796 int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1797 k1 += operand_array_length(to_cp->operands()); // to_cp might already have operands
1798 to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1799 } break;
1800
1801 // Invalid is used as the tag for the second constant pool entry
1802 // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1803 // not be seen by itself.
1804 case JVM_CONSTANT_Invalid: // fall through
1805
1806 default:
1807 {
1808 ShouldNotReachHere();
1809 } break;
1810 }
1811 } // end copy_entry_to()
1812
1813 // Search constant pool search_cp for an entry that matches this
1814 // constant pool's entry at pattern_i. Returns the index of a
1815 // matching entry or zero (0) if there is no matching entry.
find_matching_entry(int pattern_i,const constantPoolHandle & search_cp,TRAPS)1816 int ConstantPool::find_matching_entry(int pattern_i,
1817 const constantPoolHandle& search_cp, TRAPS) {
1818
1819 // index zero (0) is not used
1820 for (int i = 1; i < search_cp->length(); i++) {
1821 bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1822 if (found) {
1823 return i;
1824 }
1825 }
1826
1827 return 0; // entry not found; return unused index zero (0)
1828 } // end find_matching_entry()
1829
1830
1831 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1832 // cp2's bootstrap specifier at idx2.
compare_operand_to(int idx1,const constantPoolHandle & cp2,int idx2,TRAPS)1833 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1834 int k1 = operand_bootstrap_method_ref_index_at(idx1);
1835 int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1836 bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1837
1838 if (!match) {
1839 return false;
1840 }
1841 int argc = operand_argument_count_at(idx1);
1842 if (argc == cp2->operand_argument_count_at(idx2)) {
1843 for (int j = 0; j < argc; j++) {
1844 k1 = operand_argument_index_at(idx1, j);
1845 k2 = cp2->operand_argument_index_at(idx2, j);
1846 match = compare_entry_to(k1, cp2, k2, CHECK_false);
1847 if (!match) {
1848 return false;
1849 }
1850 }
1851 return true; // got through loop; all elements equal
1852 }
1853 return false;
1854 } // end compare_operand_to()
1855
1856 // Search constant pool search_cp for a bootstrap specifier that matches
1857 // this constant pool's bootstrap specifier at pattern_i index.
1858 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
find_matching_operand(int pattern_i,const constantPoolHandle & search_cp,int search_len,TRAPS)1859 int ConstantPool::find_matching_operand(int pattern_i,
1860 const constantPoolHandle& search_cp, int search_len, TRAPS) {
1861 for (int i = 0; i < search_len; i++) {
1862 bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1863 if (found) {
1864 return i;
1865 }
1866 }
1867 return -1; // bootstrap specifier not found; return unused index (-1)
1868 } // end find_matching_operand()
1869
1870
1871 #ifndef PRODUCT
1872
printable_name_at(int which)1873 const char* ConstantPool::printable_name_at(int which) {
1874
1875 constantTag tag = tag_at(which);
1876
1877 if (tag.is_string()) {
1878 return string_at_noresolve(which);
1879 } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1880 return klass_name_at(which)->as_C_string();
1881 } else if (tag.is_symbol()) {
1882 return symbol_at(which)->as_C_string();
1883 }
1884 return "";
1885 }
1886
1887 #endif // PRODUCT
1888
1889
1890 // JVMTI GetConstantPool support
1891
1892 // For debugging of constant pool
1893 const bool debug_cpool = false;
1894
1895 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1896
print_cpool_bytes(jint cnt,u1 * bytes)1897 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1898 const char* WARN_MSG = "Must not be such entry!";
1899 jint size = 0;
1900 u2 idx1, idx2;
1901
1902 for (jint idx = 1; idx < cnt; idx++) {
1903 jint ent_size = 0;
1904 u1 tag = *bytes++;
1905 size++; // count tag
1906
1907 printf("const #%03d, tag: %02d ", idx, tag);
1908 switch(tag) {
1909 case JVM_CONSTANT_Invalid: {
1910 printf("Invalid");
1911 break;
1912 }
1913 case JVM_CONSTANT_Unicode: {
1914 printf("Unicode %s", WARN_MSG);
1915 break;
1916 }
1917 case JVM_CONSTANT_Utf8: {
1918 u2 len = Bytes::get_Java_u2(bytes);
1919 char str[128];
1920 if (len > 127) {
1921 len = 127;
1922 }
1923 strncpy(str, (char *) (bytes+2), len);
1924 str[len] = '\0';
1925 printf("Utf8 \"%s\"", str);
1926 ent_size = 2 + len;
1927 break;
1928 }
1929 case JVM_CONSTANT_Integer: {
1930 u4 val = Bytes::get_Java_u4(bytes);
1931 printf("int %d", *(int *) &val);
1932 ent_size = 4;
1933 break;
1934 }
1935 case JVM_CONSTANT_Float: {
1936 u4 val = Bytes::get_Java_u4(bytes);
1937 printf("float %5.3ff", *(float *) &val);
1938 ent_size = 4;
1939 break;
1940 }
1941 case JVM_CONSTANT_Long: {
1942 u8 val = Bytes::get_Java_u8(bytes);
1943 printf("long " INT64_FORMAT, (int64_t) *(jlong *) &val);
1944 ent_size = 8;
1945 idx++; // Long takes two cpool slots
1946 break;
1947 }
1948 case JVM_CONSTANT_Double: {
1949 u8 val = Bytes::get_Java_u8(bytes);
1950 printf("double %5.3fd", *(jdouble *)&val);
1951 ent_size = 8;
1952 idx++; // Double takes two cpool slots
1953 break;
1954 }
1955 case JVM_CONSTANT_Class: {
1956 idx1 = Bytes::get_Java_u2(bytes);
1957 printf("class #%03d", idx1);
1958 ent_size = 2;
1959 break;
1960 }
1961 case JVM_CONSTANT_String: {
1962 idx1 = Bytes::get_Java_u2(bytes);
1963 printf("String #%03d", idx1);
1964 ent_size = 2;
1965 break;
1966 }
1967 case JVM_CONSTANT_Fieldref: {
1968 idx1 = Bytes::get_Java_u2(bytes);
1969 idx2 = Bytes::get_Java_u2(bytes+2);
1970 printf("Field #%03d, #%03d", (int) idx1, (int) idx2);
1971 ent_size = 4;
1972 break;
1973 }
1974 case JVM_CONSTANT_Methodref: {
1975 idx1 = Bytes::get_Java_u2(bytes);
1976 idx2 = Bytes::get_Java_u2(bytes+2);
1977 printf("Method #%03d, #%03d", idx1, idx2);
1978 ent_size = 4;
1979 break;
1980 }
1981 case JVM_CONSTANT_InterfaceMethodref: {
1982 idx1 = Bytes::get_Java_u2(bytes);
1983 idx2 = Bytes::get_Java_u2(bytes+2);
1984 printf("InterfMethod #%03d, #%03d", idx1, idx2);
1985 ent_size = 4;
1986 break;
1987 }
1988 case JVM_CONSTANT_NameAndType: {
1989 idx1 = Bytes::get_Java_u2(bytes);
1990 idx2 = Bytes::get_Java_u2(bytes+2);
1991 printf("NameAndType #%03d, #%03d", idx1, idx2);
1992 ent_size = 4;
1993 break;
1994 }
1995 case JVM_CONSTANT_ClassIndex: {
1996 printf("ClassIndex %s", WARN_MSG);
1997 break;
1998 }
1999 case JVM_CONSTANT_UnresolvedClass: {
2000 printf("UnresolvedClass: %s", WARN_MSG);
2001 break;
2002 }
2003 case JVM_CONSTANT_UnresolvedClassInError: {
2004 printf("UnresolvedClassInErr: %s", WARN_MSG);
2005 break;
2006 }
2007 case JVM_CONSTANT_StringIndex: {
2008 printf("StringIndex: %s", WARN_MSG);
2009 break;
2010 }
2011 }
2012 printf(";\n");
2013 bytes += ent_size;
2014 size += ent_size;
2015 }
2016 printf("Cpool size: %d\n", size);
2017 fflush(0);
2018 return;
2019 } /* end print_cpool_bytes */
2020
2021
2022 // Returns size of constant pool entry.
cpool_entry_size(jint idx)2023 jint ConstantPool::cpool_entry_size(jint idx) {
2024 switch(tag_at(idx).value()) {
2025 case JVM_CONSTANT_Invalid:
2026 case JVM_CONSTANT_Unicode:
2027 return 1;
2028
2029 case JVM_CONSTANT_Utf8:
2030 return 3 + symbol_at(idx)->utf8_length();
2031
2032 case JVM_CONSTANT_Class:
2033 case JVM_CONSTANT_String:
2034 case JVM_CONSTANT_ClassIndex:
2035 case JVM_CONSTANT_UnresolvedClass:
2036 case JVM_CONSTANT_UnresolvedClassInError:
2037 case JVM_CONSTANT_StringIndex:
2038 case JVM_CONSTANT_MethodType:
2039 case JVM_CONSTANT_MethodTypeInError:
2040 return 3;
2041
2042 case JVM_CONSTANT_MethodHandle:
2043 case JVM_CONSTANT_MethodHandleInError:
2044 return 4; //tag, ref_kind, ref_index
2045
2046 case JVM_CONSTANT_Integer:
2047 case JVM_CONSTANT_Float:
2048 case JVM_CONSTANT_Fieldref:
2049 case JVM_CONSTANT_Methodref:
2050 case JVM_CONSTANT_InterfaceMethodref:
2051 case JVM_CONSTANT_NameAndType:
2052 return 5;
2053
2054 case JVM_CONSTANT_Dynamic:
2055 case JVM_CONSTANT_DynamicInError:
2056 case JVM_CONSTANT_InvokeDynamic:
2057 // u1 tag, u2 bsm, u2 nt
2058 return 5;
2059
2060 case JVM_CONSTANT_Long:
2061 case JVM_CONSTANT_Double:
2062 return 9;
2063 }
2064 assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2065 return 1;
2066 } /* end cpool_entry_size */
2067
2068
2069 // SymbolHashMap is used to find a constant pool index from a string.
2070 // This function fills in SymbolHashMaps, one for utf8s and one for
2071 // class names, returns size of the cpool raw bytes.
hash_entries_to(SymbolHashMap * symmap,SymbolHashMap * classmap)2072 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
2073 SymbolHashMap *classmap) {
2074 jint size = 0;
2075
2076 for (u2 idx = 1; idx < length(); idx++) {
2077 u2 tag = tag_at(idx).value();
2078 size += cpool_entry_size(idx);
2079
2080 switch(tag) {
2081 case JVM_CONSTANT_Utf8: {
2082 Symbol* sym = symbol_at(idx);
2083 symmap->add_entry(sym, idx);
2084 DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
2085 break;
2086 }
2087 case JVM_CONSTANT_Class:
2088 case JVM_CONSTANT_UnresolvedClass:
2089 case JVM_CONSTANT_UnresolvedClassInError: {
2090 Symbol* sym = klass_name_at(idx);
2091 classmap->add_entry(sym, idx);
2092 DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
2093 break;
2094 }
2095 case JVM_CONSTANT_Long:
2096 case JVM_CONSTANT_Double: {
2097 idx++; // Both Long and Double take two cpool slots
2098 break;
2099 }
2100 }
2101 }
2102 return size;
2103 } /* end hash_utf8_entries_to */
2104
2105
2106 // Copy cpool bytes.
2107 // Returns:
2108 // 0, in case of OutOfMemoryError
2109 // -1, in case of internal error
2110 // > 0, count of the raw cpool bytes that have been copied
copy_cpool_bytes(int cpool_size,SymbolHashMap * tbl,unsigned char * bytes)2111 int ConstantPool::copy_cpool_bytes(int cpool_size,
2112 SymbolHashMap* tbl,
2113 unsigned char *bytes) {
2114 u2 idx1, idx2;
2115 jint size = 0;
2116 jint cnt = length();
2117 unsigned char *start_bytes = bytes;
2118
2119 for (jint idx = 1; idx < cnt; idx++) {
2120 u1 tag = tag_at(idx).value();
2121 jint ent_size = cpool_entry_size(idx);
2122
2123 assert(size + ent_size <= cpool_size, "Size mismatch");
2124
2125 *bytes = tag;
2126 DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
2127 switch(tag) {
2128 case JVM_CONSTANT_Invalid: {
2129 DBG(printf("JVM_CONSTANT_Invalid"));
2130 break;
2131 }
2132 case JVM_CONSTANT_Unicode: {
2133 assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2134 DBG(printf("JVM_CONSTANT_Unicode"));
2135 break;
2136 }
2137 case JVM_CONSTANT_Utf8: {
2138 Symbol* sym = symbol_at(idx);
2139 char* str = sym->as_utf8();
2140 // Warning! It's crashing on x86 with len = sym->utf8_length()
2141 int len = (int) strlen(str);
2142 Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2143 for (int i = 0; i < len; i++) {
2144 bytes[3+i] = (u1) str[i];
2145 }
2146 DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
2147 break;
2148 }
2149 case JVM_CONSTANT_Integer: {
2150 jint val = int_at(idx);
2151 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2152 break;
2153 }
2154 case JVM_CONSTANT_Float: {
2155 jfloat val = float_at(idx);
2156 Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2157 break;
2158 }
2159 case JVM_CONSTANT_Long: {
2160 jlong val = long_at(idx);
2161 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2162 idx++; // Long takes two cpool slots
2163 break;
2164 }
2165 case JVM_CONSTANT_Double: {
2166 jdouble val = double_at(idx);
2167 Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2168 idx++; // Double takes two cpool slots
2169 break;
2170 }
2171 case JVM_CONSTANT_Class:
2172 case JVM_CONSTANT_UnresolvedClass:
2173 case JVM_CONSTANT_UnresolvedClassInError: {
2174 *bytes = JVM_CONSTANT_Class;
2175 Symbol* sym = klass_name_at(idx);
2176 idx1 = tbl->symbol_to_value(sym);
2177 assert(idx1 != 0, "Have not found a hashtable entry");
2178 Bytes::put_Java_u2((address) (bytes+1), idx1);
2179 DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
2180 break;
2181 }
2182 case JVM_CONSTANT_String: {
2183 *bytes = JVM_CONSTANT_String;
2184 Symbol* sym = unresolved_string_at(idx);
2185 idx1 = tbl->symbol_to_value(sym);
2186 assert(idx1 != 0, "Have not found a hashtable entry");
2187 Bytes::put_Java_u2((address) (bytes+1), idx1);
2188 DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
2189 break;
2190 }
2191 case JVM_CONSTANT_Fieldref:
2192 case JVM_CONSTANT_Methodref:
2193 case JVM_CONSTANT_InterfaceMethodref: {
2194 idx1 = uncached_klass_ref_index_at(idx);
2195 idx2 = uncached_name_and_type_ref_index_at(idx);
2196 Bytes::put_Java_u2((address) (bytes+1), idx1);
2197 Bytes::put_Java_u2((address) (bytes+3), idx2);
2198 DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
2199 break;
2200 }
2201 case JVM_CONSTANT_NameAndType: {
2202 idx1 = name_ref_index_at(idx);
2203 idx2 = signature_ref_index_at(idx);
2204 Bytes::put_Java_u2((address) (bytes+1), idx1);
2205 Bytes::put_Java_u2((address) (bytes+3), idx2);
2206 DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
2207 break;
2208 }
2209 case JVM_CONSTANT_ClassIndex: {
2210 *bytes = JVM_CONSTANT_Class;
2211 idx1 = klass_index_at(idx);
2212 Bytes::put_Java_u2((address) (bytes+1), idx1);
2213 DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
2214 break;
2215 }
2216 case JVM_CONSTANT_StringIndex: {
2217 *bytes = JVM_CONSTANT_String;
2218 idx1 = string_index_at(idx);
2219 Bytes::put_Java_u2((address) (bytes+1), idx1);
2220 DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
2221 break;
2222 }
2223 case JVM_CONSTANT_MethodHandle:
2224 case JVM_CONSTANT_MethodHandleInError: {
2225 *bytes = JVM_CONSTANT_MethodHandle;
2226 int kind = method_handle_ref_kind_at(idx);
2227 idx1 = method_handle_index_at(idx);
2228 *(bytes+1) = (unsigned char) kind;
2229 Bytes::put_Java_u2((address) (bytes+2), idx1);
2230 DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
2231 break;
2232 }
2233 case JVM_CONSTANT_MethodType:
2234 case JVM_CONSTANT_MethodTypeInError: {
2235 *bytes = JVM_CONSTANT_MethodType;
2236 idx1 = method_type_index_at(idx);
2237 Bytes::put_Java_u2((address) (bytes+1), idx1);
2238 DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
2239 break;
2240 }
2241 case JVM_CONSTANT_Dynamic:
2242 case JVM_CONSTANT_DynamicInError: {
2243 *bytes = tag;
2244 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2245 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2246 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
2247 Bytes::put_Java_u2((address) (bytes+1), idx1);
2248 Bytes::put_Java_u2((address) (bytes+3), idx2);
2249 DBG(printf("JVM_CONSTANT_Dynamic: %hd %hd", idx1, idx2));
2250 break;
2251 }
2252 case JVM_CONSTANT_InvokeDynamic: {
2253 *bytes = tag;
2254 idx1 = extract_low_short_from_int(*int_at_addr(idx));
2255 idx2 = extract_high_short_from_int(*int_at_addr(idx));
2256 assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
2257 Bytes::put_Java_u2((address) (bytes+1), idx1);
2258 Bytes::put_Java_u2((address) (bytes+3), idx2);
2259 DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
2260 break;
2261 }
2262 }
2263 DBG(printf("\n"));
2264 bytes += ent_size;
2265 size += ent_size;
2266 }
2267 assert(size == cpool_size, "Size mismatch");
2268
2269 // Keep temorarily for debugging until it's stable.
2270 DBG(print_cpool_bytes(cnt, start_bytes));
2271 return (int)(bytes - start_bytes);
2272 } /* end copy_cpool_bytes */
2273
2274 #undef DBG
2275
2276
set_on_stack(const bool value)2277 void ConstantPool::set_on_stack(const bool value) {
2278 if (value) {
2279 // Only record if it's not already set.
2280 if (!on_stack()) {
2281 assert(!is_shared(), "should always be set for shared constant pools");
2282 _flags |= _on_stack;
2283 MetadataOnStackMark::record(this);
2284 }
2285 } else {
2286 // Clearing is done single-threadedly.
2287 if (!is_shared()) {
2288 _flags &= ~_on_stack;
2289 }
2290 }
2291 }
2292
2293 // JSR 292 support for patching constant pool oops after the class is linked and
2294 // the oop array for resolved references are created.
2295 // We can't do this during classfile parsing, which is how the other indexes are
2296 // patched. The other patches are applied early for some error checking
2297 // so only defer the pseudo_strings.
patch_resolved_references(GrowableArray<Handle> * cp_patches)2298 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
2299 for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
2300 Handle patch = cp_patches->at(index);
2301 if (patch.not_null()) {
2302 assert (tag_at(index).is_string(), "should only be string left");
2303 // Patching a string means pre-resolving it.
2304 // The spelling in the constant pool is ignored.
2305 // The constant reference may be any object whatever.
2306 // If it is not a real interned string, the constant is referred
2307 // to as a "pseudo-string", and must be presented to the CP
2308 // explicitly, because it may require scavenging.
2309 int obj_index = cp_to_object_index(index);
2310 pseudo_string_at_put(index, obj_index, patch());
2311 DEBUG_ONLY(cp_patches->at_put(index, Handle());)
2312 }
2313 }
2314 #ifdef ASSERT
2315 // Ensure that all the patches have been used.
2316 for (int index = 0; index < cp_patches->length(); index++) {
2317 assert(cp_patches->at(index).is_null(),
2318 "Unused constant pool patch at %d in class file %s",
2319 index,
2320 pool_holder()->external_name());
2321 }
2322 #endif // ASSERT
2323 }
2324
2325 // Printing
2326
print_on(outputStream * st) const2327 void ConstantPool::print_on(outputStream* st) const {
2328 assert(is_constantPool(), "must be constantPool");
2329 st->print_cr("%s", internal_name());
2330 if (flags() != 0) {
2331 st->print(" - flags: 0x%x", flags());
2332 if (has_preresolution()) st->print(" has_preresolution");
2333 if (on_stack()) st->print(" on_stack");
2334 st->cr();
2335 }
2336 if (pool_holder() != NULL) {
2337 st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
2338 }
2339 st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
2340 st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
2341 st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
2342 st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
2343
2344 for (int index = 1; index < length(); index++) { // Index 0 is unused
2345 ((ConstantPool*)this)->print_entry_on(index, st);
2346 switch (tag_at(index).value()) {
2347 case JVM_CONSTANT_Long :
2348 case JVM_CONSTANT_Double :
2349 index++; // Skip entry following eigth-byte constant
2350 }
2351
2352 }
2353 st->cr();
2354 }
2355
2356 // Print one constant pool entry
print_entry_on(const int index,outputStream * st)2357 void ConstantPool::print_entry_on(const int index, outputStream* st) {
2358 EXCEPTION_MARK;
2359 st->print(" - %3d : ", index);
2360 tag_at(index).print_on(st);
2361 st->print(" : ");
2362 switch (tag_at(index).value()) {
2363 case JVM_CONSTANT_Class :
2364 { Klass* k = klass_at(index, CATCH);
2365 guarantee(k != NULL, "need klass");
2366 k->print_value_on(st);
2367 st->print(" {" PTR_FORMAT "}", p2i(k));
2368 }
2369 break;
2370 case JVM_CONSTANT_Fieldref :
2371 case JVM_CONSTANT_Methodref :
2372 case JVM_CONSTANT_InterfaceMethodref :
2373 st->print("klass_index=%d", uncached_klass_ref_index_at(index));
2374 st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
2375 break;
2376 case JVM_CONSTANT_String :
2377 if (is_pseudo_string_at(index)) {
2378 oop anObj = pseudo_string_at(index);
2379 anObj->print_value_on(st);
2380 st->print(" {" PTR_FORMAT "}", p2i(anObj));
2381 } else {
2382 unresolved_string_at(index)->print_value_on(st);
2383 }
2384 break;
2385 case JVM_CONSTANT_Integer :
2386 st->print("%d", int_at(index));
2387 break;
2388 case JVM_CONSTANT_Float :
2389 st->print("%f", float_at(index));
2390 break;
2391 case JVM_CONSTANT_Long :
2392 st->print_jlong(long_at(index));
2393 break;
2394 case JVM_CONSTANT_Double :
2395 st->print("%lf", double_at(index));
2396 break;
2397 case JVM_CONSTANT_NameAndType :
2398 st->print("name_index=%d", name_ref_index_at(index));
2399 st->print(" signature_index=%d", signature_ref_index_at(index));
2400 break;
2401 case JVM_CONSTANT_Utf8 :
2402 symbol_at(index)->print_value_on(st);
2403 break;
2404 case JVM_CONSTANT_ClassIndex: {
2405 int name_index = *int_at_addr(index);
2406 st->print("klass_index=%d ", name_index);
2407 symbol_at(name_index)->print_value_on(st);
2408 }
2409 break;
2410 case JVM_CONSTANT_UnresolvedClass : // fall-through
2411 case JVM_CONSTANT_UnresolvedClassInError: {
2412 CPKlassSlot kslot = klass_slot_at(index);
2413 int resolved_klass_index = kslot.resolved_klass_index();
2414 int name_index = kslot.name_index();
2415 assert(tag_at(name_index).is_symbol(), "sanity");
2416
2417 Klass* klass = resolved_klasses()->at(resolved_klass_index);
2418 if (klass != NULL) {
2419 klass->print_value_on(st);
2420 } else {
2421 symbol_at(name_index)->print_value_on(st);
2422 }
2423 }
2424 break;
2425 case JVM_CONSTANT_MethodHandle :
2426 case JVM_CONSTANT_MethodHandleInError :
2427 st->print("ref_kind=%d", method_handle_ref_kind_at(index));
2428 st->print(" ref_index=%d", method_handle_index_at(index));
2429 break;
2430 case JVM_CONSTANT_MethodType :
2431 case JVM_CONSTANT_MethodTypeInError :
2432 st->print("signature_index=%d", method_type_index_at(index));
2433 break;
2434 case JVM_CONSTANT_Dynamic :
2435 case JVM_CONSTANT_DynamicInError :
2436 {
2437 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2438 st->print(" type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2439 int argc = invoke_dynamic_argument_count_at(index);
2440 if (argc > 0) {
2441 for (int arg_i = 0; arg_i < argc; arg_i++) {
2442 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2443 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2444 }
2445 st->print("}");
2446 }
2447 }
2448 break;
2449 case JVM_CONSTANT_InvokeDynamic :
2450 {
2451 st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
2452 st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
2453 int argc = invoke_dynamic_argument_count_at(index);
2454 if (argc > 0) {
2455 for (int arg_i = 0; arg_i < argc; arg_i++) {
2456 int arg = invoke_dynamic_argument_index_at(index, arg_i);
2457 st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2458 }
2459 st->print("}");
2460 }
2461 }
2462 break;
2463 default:
2464 ShouldNotReachHere();
2465 break;
2466 }
2467 st->cr();
2468 }
2469
print_value_on(outputStream * st) const2470 void ConstantPool::print_value_on(outputStream* st) const {
2471 assert(is_constantPool(), "must be constantPool");
2472 st->print("constant pool [%d]", length());
2473 if (has_preresolution()) st->print("/preresolution");
2474 if (operands() != NULL) st->print("/operands[%d]", operands()->length());
2475 print_address_on(st);
2476 if (pool_holder() != NULL) {
2477 st->print(" for ");
2478 pool_holder()->print_value_on(st);
2479 bool extra = (pool_holder()->constants() != this);
2480 if (extra) st->print(" (extra)");
2481 }
2482 if (cache() != NULL) {
2483 st->print(" cache=" PTR_FORMAT, p2i(cache()));
2484 }
2485 }
2486
2487 #if INCLUDE_SERVICES
2488 // Size Statistics
collect_statistics(KlassSizeStats * sz) const2489 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2490 sz->_cp_all_bytes += (sz->_cp_bytes = sz->count(this));
2491 sz->_cp_all_bytes += (sz->_cp_tags_bytes = sz->count_array(tags()));
2492 sz->_cp_all_bytes += (sz->_cp_cache_bytes = sz->count(cache()));
2493 sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2494 sz->_cp_all_bytes += (sz->_cp_refmap_bytes = sz->count_array(reference_map()));
2495
2496 sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2497 sz->_cp_refmap_bytes;
2498 sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2499 }
2500 #endif // INCLUDE_SERVICES
2501
2502 // Verification
2503
verify_on(outputStream * st)2504 void ConstantPool::verify_on(outputStream* st) {
2505 guarantee(is_constantPool(), "object must be constant pool");
2506 for (int i = 0; i< length(); i++) {
2507 constantTag tag = tag_at(i);
2508 if (tag.is_klass() || tag.is_unresolved_klass()) {
2509 guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2510 } else if (tag.is_symbol()) {
2511 CPSlot entry = slot_at(i);
2512 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2513 } else if (tag.is_string()) {
2514 CPSlot entry = slot_at(i);
2515 guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2516 }
2517 }
2518 if (cache() != NULL) {
2519 // Note: cache() can be NULL before a class is completely setup or
2520 // in temporary constant pools used during constant pool merging
2521 guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2522 }
2523 if (pool_holder() != NULL) {
2524 // Note: pool_holder() can be NULL in temporary constant pools
2525 // used during constant pool merging
2526 guarantee(pool_holder()->is_klass(), "should be klass");
2527 }
2528 }
2529
2530
~SymbolHashMap()2531 SymbolHashMap::~SymbolHashMap() {
2532 SymbolHashMapEntry* next;
2533 for (int i = 0; i < _table_size; i++) {
2534 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
2535 next = cur->next();
2536 delete(cur);
2537 }
2538 }
2539 FREE_C_HEAP_ARRAY(SymbolHashMapBucket, _buckets);
2540 }
2541
add_entry(Symbol * sym,u2 value)2542 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2543 char *str = sym->as_utf8();
2544 unsigned int hash = compute_hash(str, sym->utf8_length());
2545 unsigned int index = hash % table_size();
2546
2547 // check if already in map
2548 // we prefer the first entry since it is more likely to be what was used in
2549 // the class file
2550 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2551 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2552 if (en->hash() == hash && en->symbol() == sym) {
2553 return; // already there
2554 }
2555 }
2556
2557 SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2558 entry->set_next(bucket(index));
2559 _buckets[index].set_entry(entry);
2560 assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2561 }
2562
find_entry(Symbol * sym)2563 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2564 assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2565 char *str = sym->as_utf8();
2566 int len = sym->utf8_length();
2567 unsigned int hash = SymbolHashMap::compute_hash(str, len);
2568 unsigned int index = hash % table_size();
2569 for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2570 assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2571 if (en->hash() == hash && en->symbol() == sym) {
2572 return en;
2573 }
2574 }
2575 return NULL;
2576 }
2577
initialize_table(int table_size)2578 void SymbolHashMap::initialize_table(int table_size) {
2579 _table_size = table_size;
2580 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol);
2581 for (int index = 0; index < table_size; index++) {
2582 _buckets[index].clear();
2583 }
2584 }
2585