1 /*
  2  * Copyright (c) 1998, 2024, 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 "cds/archiveBuilder.hpp"
 27 #include "cds/cdsConfig.hpp"
 28 #include "cds/classPrelinker.hpp"
 29 #include "cds/heapShared.hpp"
 30 #include "classfile/resolutionErrors.hpp"
 31 #include "classfile/systemDictionary.hpp"
 32 #include "classfile/systemDictionaryShared.hpp"
 33 #include "classfile/vmClasses.hpp"
 34 #include "code/codeCache.hpp"
 35 #include "interpreter/bytecodeStream.hpp"
 36 #include "interpreter/bytecodes.hpp"
 37 #include "interpreter/interpreter.hpp"
 38 #include "interpreter/linkResolver.hpp"
 39 #include "interpreter/rewriter.hpp"
 40 #include "logging/log.hpp"
 41 #include "logging/logStream.hpp"
 42 #include "memory/metadataFactory.hpp"
 43 #include "memory/metaspaceClosure.hpp"
 44 #include "memory/resourceArea.hpp"
 45 #include "oops/access.inline.hpp"
 46 #include "oops/compressedOops.hpp"
 47 #include "oops/constantPool.inline.hpp"
 48 #include "oops/cpCache.inline.hpp"
 49 #include "oops/method.inline.hpp"
 50 #include "oops/objArrayOop.inline.hpp"
 51 #include "oops/oop.inline.hpp"
 52 #include "oops/resolvedFieldEntry.hpp"
 53 #include "oops/resolvedIndyEntry.hpp"
 54 #include "oops/resolvedMethodEntry.hpp"
 55 #include "prims/methodHandles.hpp"
 56 #include "runtime/arguments.hpp"
 57 #include "runtime/atomic.hpp"
 58 #include "runtime/handles.inline.hpp"
 59 #include "runtime/mutexLocker.hpp"
 60 #include "runtime/synchronizer.hpp"
 61 #include "runtime/vm_version.hpp"
 62 #include "utilities/macros.hpp"
 63 
 64 // Implementation of ConstantPoolCache
 65 
 66 template <class T>
 67 static Array<T>* initialize_resolved_entries_array(ClassLoaderData* loader_data, GrowableArray<T> entries, TRAPS) {
 68   Array<T>* resolved_entries;
 69   if (entries.length() != 0) {
 70     resolved_entries = MetadataFactory::new_array<T>(loader_data, entries.length(), CHECK_NULL);
 71     for (int i = 0; i < entries.length(); i++) {
 72       resolved_entries->at_put(i, entries.at(i));
 73     }
 74     return resolved_entries;
 75   }
 76   return nullptr;
 77 }
 78 
 79 void ConstantPoolCache::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
 80                                                        int method_index,
 81                                                        const methodHandle& method,
 82                                                        int vtable_index,
 83                                                        bool sender_is_interface) {
 84   bool is_vtable_call = (vtable_index >= 0);  // FIXME: split this method on this boolean
 85   assert(method->interpreter_entry() != nullptr, "should have been set at this point");
 86   assert(!method->is_obsolete(),  "attempt to write obsolete method to cpCache");
 87 
 88   int byte_no = -1;
 89   bool change_to_virtual = false;
 90   InstanceKlass* holder = nullptr;  // have to declare this outside the switch
 91   ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
 92   switch (invoke_code) {
 93     case Bytecodes::_invokeinterface:
 94       holder = method->method_holder();
 95       // check for private interface method invocations
 96       if (vtable_index == Method::nonvirtual_vtable_index && holder->is_interface() ) {
 97         assert(method->is_private(), "unexpected non-private method");
 98         assert(method->can_be_statically_bound(), "unexpected non-statically-bound method");
 99 
100         method_entry->set_flags((                             1      << ResolvedMethodEntry::is_vfinal_shift) |
101                                 ((method->is_final_method() ? 1 : 0) << ResolvedMethodEntry::is_final_shift));
102         method_entry->fill_in((u1)as_TosState(method->result_type()), (u2)method()->size_of_parameters());
103         assert(method_entry->is_vfinal(), "flags must be set");
104         method_entry->set_method(method());
105         byte_no = 2;
106         method_entry->set_klass(holder);
107         break;
108       }
109       else {
110         // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
111         // instruction links to a non-interface method (in Object). This can happen when
112         // an interface redeclares an Object method (like CharSequence declaring toString())
113         // or when invokeinterface is used explicitly.
114         // In that case, the method has no itable index and must be invoked as a virtual.
115         // Set a flag to keep track of this corner case.
116         assert(holder->is_interface() || holder == vmClasses::Object_klass(), "unexpected holder class");
117         assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
118         change_to_virtual = true;
119 
120         // ...and fall through as if we were handling invokevirtual:
121       }
122     case Bytecodes::_invokevirtual:
123       {
124         if (!is_vtable_call) {
125           assert(method->can_be_statically_bound(), "");
126           method_entry->set_flags((                             1      << ResolvedMethodEntry::is_vfinal_shift) |
127                                   ((method->is_final_method() ? 1 : 0) << ResolvedMethodEntry::is_final_shift)  |
128                                   ((change_to_virtual         ? 1 : 0) << ResolvedMethodEntry::is_forced_virtual_shift));
129           method_entry->fill_in((u1)as_TosState(method->result_type()), (u2)method()->size_of_parameters());
130           assert(method_entry->is_vfinal(), "flags must be set");
131           method_entry->set_method(method());
132         } else {
133           assert(!method->can_be_statically_bound(), "");
134           assert(vtable_index >= 0, "valid index");
135           assert(!method->is_final_method(), "sanity");
136           method_entry->set_flags((change_to_virtual ? 1 : 0) << ResolvedMethodEntry::is_forced_virtual_shift);
137           method_entry->fill_in((u1)as_TosState(method->result_type()), (u2)method()->size_of_parameters());
138           assert(!method_entry->is_vfinal(), "flags must not be set");
139           method_entry->set_table_index(vtable_index);
140         }
141         byte_no = 2;
142         break;
143       }
144 
145     case Bytecodes::_invokespecial:
146     case Bytecodes::_invokestatic: {
147       assert(!is_vtable_call, "");
148       // Note:  Read and preserve the value of the is_vfinal flag on any
149       // invokevirtual bytecode shared with this constant pool cache entry.
150       // It is cheap and safe to consult is_vfinal() at all times.
151       // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
152       bool vfinal = method_entry->is_vfinal();
153       method_entry->set_flags(((method->is_final_method() ? 1 : 0) << ResolvedMethodEntry::is_final_shift));
154       assert(vfinal == method_entry->is_vfinal(), "Vfinal flag must be preserved");
155       method_entry->fill_in((u1)as_TosState(method->result_type()), (u2)method()->size_of_parameters());
156       method_entry->set_method(method());
157       byte_no = 1;
158       break;
159     }
160     default:
161       ShouldNotReachHere();
162       break;
163   }
164 
165   // Note:  byte_no also appears in TemplateTable::resolve.
166   if (byte_no == 1) {
167     assert(invoke_code != Bytecodes::_invokevirtual &&
168            invoke_code != Bytecodes::_invokeinterface, "");
169     bool do_resolve = true;
170     // Don't mark invokespecial to method as resolved if sender is an interface.  The receiver
171     // has to be checked that it is a subclass of the current class every time this bytecode
172     // is executed.
173     if (invoke_code == Bytecodes::_invokespecial && sender_is_interface &&
174         method->name() != vmSymbols::object_initializer_name()) {
175       do_resolve = false;
176     }
177     if (invoke_code == Bytecodes::_invokestatic) {
178       assert(method->method_holder()->is_initialized() ||
179              method->method_holder()->is_reentrant_initialization(JavaThread::current()),
180              "invalid class initialization state for invoke_static");
181 
182       if (!VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
183         // Don't mark invokestatic to method as resolved if the holder class has not yet completed
184         // initialization. An invokestatic must only proceed if the class is initialized, but if
185         // we resolve it before then that class initialization check is skipped.
186         //
187         // When fast class initialization checks are supported (VM_Version::supports_fast_class_init_checks() == true),
188         // template interpreter supports fast class initialization check for
189         // invokestatic which doesn't require call site re-resolution to
190         // enforce class initialization barrier.
191         do_resolve = false;
192       }
193     }
194     if (do_resolve) {
195       method_entry->set_bytecode1(invoke_code);
196     }
197   } else if (byte_no == 2)  {
198     if (change_to_virtual) {
199       assert(invoke_code == Bytecodes::_invokeinterface, "");
200       // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
201       //
202       // Workaround for the case where we encounter an invokeinterface, but we
203       // should really have an _invokevirtual since the resolved method is a
204       // virtual method in java.lang.Object. This is a corner case in the spec
205       // but is presumably legal. javac does not generate this code.
206       //
207       // We do not set bytecode_1() to _invokeinterface, because that is the
208       // bytecode # used by the interpreter to see if it is resolved.  In this
209       // case, the method gets reresolved with caller for each interface call
210       // because the actual selected method may not be public.
211       //
212       // We set bytecode_2() to _invokevirtual.
213       // See also interpreterRuntime.cpp. (8/25/2000)
214       invoke_code = Bytecodes::_invokevirtual;
215     } else {
216       assert(invoke_code == Bytecodes::_invokevirtual ||
217              (invoke_code == Bytecodes::_invokeinterface &&
218               ((method->is_private() ||
219                 (method->is_final() && method->method_holder() == vmClasses::Object_klass())))),
220              "unexpected invocation mode");
221       if (invoke_code == Bytecodes::_invokeinterface &&
222           (method->is_private() || method->is_final())) {
223         // We set bytecode_1() to _invokeinterface, because that is the
224         // bytecode # used by the interpreter to see if it is resolved.
225         // We set bytecode_2() to _invokevirtual.
226         method_entry->set_bytecode1(invoke_code);
227       }
228     }
229     // set up for invokevirtual, even if linking for invokeinterface also:
230     method_entry->set_bytecode2(invoke_code);
231   } else {
232     ShouldNotReachHere();
233   }
234 }
235 
236 void ConstantPoolCache::set_direct_call(Bytecodes::Code invoke_code, int method_index, const methodHandle& method,
237                                         bool sender_is_interface) {
238   int index = Method::nonvirtual_vtable_index;
239   // index < 0; FIXME: inline and customize set_direct_or_vtable_call
240   set_direct_or_vtable_call(invoke_code, method_index, method, index, sender_is_interface);
241 }
242 
243 void ConstantPoolCache::set_vtable_call(Bytecodes::Code invoke_code, int method_index, const methodHandle& method, int index) {
244   // either the method is a miranda or its holder should accept the given index
245   assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
246   // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
247   set_direct_or_vtable_call(invoke_code, method_index, method, index, false);
248 }
249 
250 void ConstantPoolCache::set_itable_call(Bytecodes::Code invoke_code,
251                                         int method_index,
252                                         Klass* referenced_klass,
253                                         const methodHandle& method, int index) {
254   assert(method->method_holder()->verify_itable_index(index), "");
255   assert(invoke_code == Bytecodes::_invokeinterface, "");
256   InstanceKlass* interf = method->method_holder();
257   assert(interf->is_interface(), "must be an interface");
258   assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
259   ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
260   method_entry->set_klass(static_cast<InstanceKlass*>(referenced_klass));
261   method_entry->set_method(method());
262   method_entry->fill_in((u1)as_TosState(method->result_type()), (u2)method()->size_of_parameters());
263   method_entry->set_bytecode1(Bytecodes::_invokeinterface);
264 }
265 
266 ResolvedMethodEntry* ConstantPoolCache::set_method_handle(int method_index, const CallInfo &call_info) {
267   // NOTE: This method entry can be the subject of data races.
268   // There are three words to update: flags, refs[appendix_index], method (in that order).
269   // Writers must store all other values before method.
270   // Readers must test the method first for non-null before reading other fields.
271   // Competing writers must acquire exclusive access via a lock.
272   // A losing writer waits on the lock until the winner writes the method and leaves
273   // the lock, so that when the losing writer returns, he can use the linked
274   // cache entry.
275 
276   // Lock fields to write
277   Bytecodes::Code invoke_code = Bytecodes::_invokehandle;
278 
279   JavaThread* current = JavaThread::current();
280   objArrayHandle resolved_references(current, constant_pool()->resolved_references());
281   // Use the resolved_references() lock for this cpCache entry.
282   // resolved_references are created for all classes with Invokedynamic, MethodHandle
283   // or MethodType constant pool cache entries.
284   assert(resolved_references() != nullptr,
285          "a resolved_references array should have been created for this class");
286   ObjectLocker ol(resolved_references, current);
287 
288   ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
289   if (method_entry->is_resolved(invoke_code)) {
290     return method_entry;
291   }
292 
293   Method* adapter            = call_info.resolved_method();
294   const Handle appendix      = call_info.resolved_appendix();
295   const bool has_appendix    = appendix.not_null();
296 
297   // Write the flags.
298   // MHs are always sig-poly and have a local signature.
299   method_entry->fill_in((u1)as_TosState(adapter->result_type()), (u2)adapter->size_of_parameters());
300   method_entry->set_flags(((has_appendix    ? 1 : 0) << ResolvedMethodEntry::has_appendix_shift        ) |
301                           (                   1      << ResolvedMethodEntry::has_local_signature_shift ) |
302                           (                   1      << ResolvedMethodEntry::is_final_shift            ));
303 
304   // Method handle invokes use both a method and a resolved references index.
305   // refs[appendix_index], if not null, contains a value passed as a trailing argument to the adapter.
306   // In the general case, this could be the call site's MethodType,
307   // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
308   // method_entry->method() contains the adapter method which manages the actual call.
309   // In the general case, this is a compiled LambdaForm.
310   // (The Java code is free to optimize these calls by binding other
311   // sorts of methods and appendices to call sites.)
312   // JVM-level linking is via the method, as if for invokespecial, and signatures are erased.
313   // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
314   // Even with the appendix, the method will never take more than 255 parameter slots.
315   //
316   // This means that given a call site like (List)mh.invoke("foo"),
317   // the method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
318   // not '(Ljava/lang/String;)Ljava/util/List;'.
319   // The fact that String and List are involved is encoded in the MethodType in refs[appendix_index].
320   // This allows us to create fewer Methods, while keeping type safety.
321   //
322 
323   // Store appendix, if any.
324   if (has_appendix) {
325     const int appendix_index = method_entry->resolved_references_index();
326     assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
327     assert(resolved_references->obj_at(appendix_index) == nullptr, "init just once");
328     resolved_references->obj_at_put(appendix_index, appendix());
329   }
330 
331   method_entry->set_method(adapter); // This must be the last one to set (see NOTE above)!
332 
333   // The interpreter assembly code does not check byte_2,
334   // but it is used by is_resolved, method_if_resolved, etc.
335   method_entry->set_bytecode1(invoke_code);
336 
337   assert(has_appendix == method_entry->has_appendix(), "proper storage of appendix flag");
338   assert(method_entry->has_local_signature(), "proper storage of signature flag");
339   return method_entry;
340 }
341 
342 Method* ConstantPoolCache::method_if_resolved(int method_index) const {
343   // Decode the action of set_method and set_interface_call
344   ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
345 
346   Bytecodes::Code invoke_code = (Bytecodes::Code)method_entry->bytecode1();
347   switch (invoke_code) {
348     case Bytecodes::_invokeinterface:
349     case Bytecodes::_invokestatic:
350     case Bytecodes::_invokespecial:
351       assert(!method_entry->has_appendix(), "");
352       // fall through
353     case Bytecodes::_invokehandle:
354       return method_entry->method();
355     case Bytecodes::_invokedynamic:
356       ShouldNotReachHere();
357     default:
358       assert(invoke_code == (Bytecodes::Code)0, "unexpected bytecode");
359       break;
360   }
361 
362   invoke_code = (Bytecodes::Code)method_entry->bytecode2();
363   if (invoke_code == Bytecodes::_invokevirtual) {
364     if (method_entry->is_vfinal()) {
365       return method_entry->method();
366     } else {
367       int holder_index = constant_pool()->uncached_klass_ref_index_at(method_entry->constant_pool_index());
368       if (constant_pool()->tag_at(holder_index).is_klass()) {
369         Klass* klass = constant_pool()->resolved_klass_at(holder_index);
370         return klass->method_at_vtable(method_entry->table_index());
371       }
372     }
373   }
374   return nullptr;
375 }
376 
377 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
378                                      const intStack& invokedynamic_map,
379                                      const GrowableArray<ResolvedIndyEntry> indy_entries,
380                                      const GrowableArray<ResolvedFieldEntry> field_entries,
381                                      const GrowableArray<ResolvedMethodEntry> method_entries,
382                                      TRAPS) {
383 
384   int size = ConstantPoolCache::size();
385 
386   // Initialize resolved entry arrays with available data
387   Array<ResolvedFieldEntry>* resolved_field_entries = initialize_resolved_entries_array(loader_data, field_entries, CHECK_NULL);
388   Array<ResolvedIndyEntry>* resolved_indy_entries = initialize_resolved_entries_array(loader_data, indy_entries, CHECK_NULL);
389   Array<ResolvedMethodEntry>* resolved_method_entries = initialize_resolved_entries_array(loader_data, method_entries, CHECK_NULL);
390 
391   return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
392               ConstantPoolCache(invokedynamic_map, resolved_indy_entries, resolved_field_entries, resolved_method_entries);
393 }
394 
395 // Record the GC marking cycle when redefined vs. when found in the loom stack chunks.
396 void ConstantPoolCache::record_gc_epoch() {
397   _gc_epoch = CodeCache::gc_epoch();
398 }
399 
400 #if INCLUDE_CDS
401 void ConstantPoolCache::remove_unshareable_info() {
402   assert(CDSConfig::is_dumping_archive(), "sanity");
403 
404   if (_resolved_indy_entries != nullptr) {
405     for (int i = 0; i < _resolved_indy_entries->length(); i++) {
406       resolved_indy_entry_at(i)->remove_unshareable_info();
407     }
408   }
409   if (_resolved_field_entries != nullptr) {
410     remove_resolved_field_entries_if_non_deterministic();
411   }
412   if (_resolved_method_entries != nullptr) {
413     remove_resolved_method_entries_if_non_deterministic();
414   }
415 }
416 
417 void ConstantPoolCache::remove_resolved_field_entries_if_non_deterministic() {
418   ConstantPool* cp = constant_pool();
419   ConstantPool* src_cp =  ArchiveBuilder::current()->get_source_addr(cp);
420   for (int i = 0; i < _resolved_field_entries->length(); i++) {
421     ResolvedFieldEntry* rfi = _resolved_field_entries->adr_at(i);
422     int cp_index = rfi->constant_pool_index();
423     bool archived = false;
424     bool resolved = rfi->is_resolved(Bytecodes::_getfield)  ||
425                     rfi->is_resolved(Bytecodes::_putfield);
426     if (resolved && ClassPrelinker::is_resolution_deterministic(src_cp, cp_index)) {
427       rfi->mark_and_relocate();
428       archived = true;
429     } else {
430       rfi->remove_unshareable_info();
431     }
432     if (resolved) {
433       LogStreamHandle(Trace, cds, resolve) log;
434       if (log.is_enabled()) {
435         ResourceMark rm;
436         int klass_cp_index = cp->uncached_klass_ref_index_at(cp_index);
437         Symbol* klass_name = cp->klass_name_at(klass_cp_index);
438         Symbol* name = cp->uncached_name_ref_at(cp_index);
439         Symbol* signature = cp->uncached_signature_ref_at(cp_index);
440         log.print("%s field  CP entry [%3d]: %s %s %s.%s:%s",
441                   (archived ? "archived" : "reverted"),
442                   cp_index,
443                   cp->pool_holder()->name()->as_C_string(),
444                   (archived ? "=>" : "  "),
445                   klass_name->as_C_string(), name->as_C_string(), signature->as_C_string());
446       }
447     }
448     ArchiveBuilder::alloc_stats()->record_field_cp_entry(archived, resolved && !archived);
449   }
450 }
451 
452 void ConstantPoolCache::remove_resolved_method_entries_if_non_deterministic() {
453   ConstantPool* cp = constant_pool();
454   ConstantPool* src_cp =  ArchiveBuilder::current()->get_source_addr(cp);
455   for (int i = 0; i < _resolved_method_entries->length(); i++) {
456     ResolvedMethodEntry* rme = _resolved_method_entries->adr_at(i);
457     int cp_index = rme->constant_pool_index();
458     bool archived = false;
459     bool resolved = rme->is_resolved(Bytecodes::_invokevirtual)   ||
460                     rme->is_resolved(Bytecodes::_invokespecial)   ||
461                     rme->is_resolved(Bytecodes::_invokeinterface);
462 
463     // Just for safety -- this should not happen, but do not archive if we ever see this.
464     resolved &= !(rme->is_resolved(Bytecodes::_invokehandle) ||
465                   rme->is_resolved(Bytecodes::_invokestatic));
466 
467     if (resolved && can_archive_resolved_method(rme)) {
468       rme->mark_and_relocate(src_cp);
469       archived = true;
470     } else {
471       rme->remove_unshareable_info();
472     }
473     if (resolved) {
474       LogStreamHandle(Trace, cds, resolve) log;
475       if (log.is_enabled()) {
476         ResourceMark rm;
477         int klass_cp_index = cp->uncached_klass_ref_index_at(cp_index);
478         Symbol* klass_name = cp->klass_name_at(klass_cp_index);
479         Symbol* name = cp->uncached_name_ref_at(cp_index);
480         Symbol* signature = cp->uncached_signature_ref_at(cp_index);
481         log.print("%s%s method CP entry [%3d]: %s %s.%s:%s",
482                   (archived ? "archived" : "reverted"),
483                   (rme->is_resolved(Bytecodes::_invokeinterface) ? " interface" : ""),
484                   cp_index,
485                   cp->pool_holder()->name()->as_C_string(),
486                   klass_name->as_C_string(), name->as_C_string(), signature->as_C_string());
487         if (archived) {
488           Klass* resolved_klass = cp->resolved_klass_at(klass_cp_index);
489           log.print(" => %s%s",
490                     resolved_klass->name()->as_C_string(),
491                     (rme->is_resolved(Bytecodes::_invokestatic) ? " *** static" : ""));
492         }
493       }
494       ArchiveBuilder::alloc_stats()->record_method_cp_entry(archived, resolved && !archived);
495     }
496   }
497 }
498 
499 bool ConstantPoolCache::can_archive_resolved_method(ResolvedMethodEntry* method_entry) {
500   InstanceKlass* pool_holder = constant_pool()->pool_holder();
501   if (!(pool_holder->is_shared_boot_class() || pool_holder->is_shared_platform_class() ||
502         pool_holder->is_shared_app_class())) {
503     // Archiving resolved cp entries for classes from non-builtin loaders
504     // is not yet supported.
505     return false;
506   }
507 
508   if (CDSConfig::is_dumping_dynamic_archive()) {
509     // InstanceKlass::methods() has been resorted. We need to
510     // update the vtable_index in method_entry (not implemented)
511     return false;
512   }
513 
514   if (!method_entry->is_resolved(Bytecodes::_invokevirtual)) {
515     if (method_entry->method() == nullptr) {
516       return false;
517     }
518     if (method_entry->method()->is_continuation_native_intrinsic()) {
519       return false; // FIXME: corresponding stub is generated on demand during method resolution (see LinkResolver::resolve_static_call).
520     }
521   }
522 
523   int cp_index = method_entry->constant_pool_index();
524   ConstantPool* src_cp = ArchiveBuilder::current()->get_source_addr(constant_pool());
525   assert(src_cp->tag_at(cp_index).is_method() || src_cp->tag_at(cp_index).is_interface_method(), "sanity");
526 
527   if (!ClassPrelinker::is_resolution_deterministic(src_cp, cp_index)) {
528     return false;
529   }
530 
531   if (method_entry->is_resolved(Bytecodes::_invokeinterface) ||
532       method_entry->is_resolved(Bytecodes::_invokevirtual) ||
533       method_entry->is_resolved(Bytecodes::_invokespecial)) {
534     return true;
535   } else {
536     // invokestatic and invokehandle are not supported yet.
537     return false;
538   }
539 
540 }
541 #endif // INCLUDE_CDS
542 
543 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
544   assert(!is_shared(), "shared caches are not deallocated");
545   data->remove_handle(_resolved_references);
546   set_resolved_references(OopHandle());
547   MetadataFactory::free_array<u2>(data, _reference_map);
548   set_reference_map(nullptr);
549 #if INCLUDE_CDS
550   if (_resolved_indy_entries != nullptr) {
551     MetadataFactory::free_array<ResolvedIndyEntry>(data, _resolved_indy_entries);
552     _resolved_indy_entries = nullptr;
553   }
554   if (_resolved_field_entries != nullptr) {
555     MetadataFactory::free_array<ResolvedFieldEntry>(data, _resolved_field_entries);
556     _resolved_field_entries = nullptr;
557   }
558   if (_resolved_method_entries != nullptr) {
559     MetadataFactory::free_array<ResolvedMethodEntry>(data, _resolved_method_entries);
560     _resolved_method_entries = nullptr;
561   }
562 #endif
563 }
564 
565 #if INCLUDE_CDS_JAVA_HEAP
566 oop ConstantPoolCache::archived_references() {
567   if (_archived_references_index < 0) {
568     return nullptr;
569   }
570   return HeapShared::get_root(_archived_references_index);
571 }
572 
573 void ConstantPoolCache::clear_archived_references() {
574   if (_archived_references_index >= 0) {
575     HeapShared::clear_root(_archived_references_index);
576     _archived_references_index = -1;
577   }
578 }
579 
580 void ConstantPoolCache::set_archived_references(int root_index) {
581   assert(CDSConfig::is_dumping_heap(), "sanity");
582   _archived_references_index = root_index;
583 }
584 #endif
585 
586 #if INCLUDE_JVMTI
587 static void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
588   ResourceMark rm;
589 
590   if (!(*trace_name_printed)) {
591     log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
592     *trace_name_printed = true;
593   }
594   log_trace(redefine, class, update, constantpool)
595     ("cpc %s entry update: %s", entry_type, new_method->external_name());
596 }
597 
598 // RedefineClasses() API support:
599 // If any entry of this ConstantPoolCache points to any of
600 // old_methods, replace it with the corresponding new_method.
601 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) {
602   if (_resolved_indy_entries != nullptr) {
603     for (int j = 0; j < _resolved_indy_entries->length(); j++) {
604       Method* old_method = resolved_indy_entry_at(j)->method();
605       if (old_method == nullptr || !old_method->is_old()) {
606         continue;
607       }
608       assert(!old_method->is_deleted(), "cannot delete these methods");
609       Method* new_method = old_method->get_new_method();
610       resolved_indy_entry_at(j)->adjust_method_entry(new_method);
611       log_adjust("indy", old_method, new_method, trace_name_printed);
612     }
613   }
614   if (_resolved_method_entries != nullptr) {
615     for (int i = 0; i < _resolved_method_entries->length(); i++) {
616       ResolvedMethodEntry* method_entry = resolved_method_entry_at(i);
617       // get interesting method entry
618       Method* old_method = method_entry->method();
619       if (old_method == nullptr || !old_method->is_old()) {
620         continue; // skip uninteresting entries
621       }
622       if (old_method->is_deleted()) {
623         // clean up entries with deleted methods
624         method_entry->reset_entry();
625         continue;
626       }
627       Method* new_method = old_method->get_new_method();
628       method_entry->adjust_method_entry(new_method);
629       log_adjust("non-indy", old_method, new_method, trace_name_printed);
630     }
631   }
632 }
633 
634 // the constant pool cache should never contain old or obsolete methods
635 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
636   ResourceMark rm;
637   if (_resolved_indy_entries != nullptr) {
638     for (int i = 0; i < _resolved_indy_entries->length(); i++) {
639       Method* m = resolved_indy_entry_at(i)->method();
640       if (m != nullptr && !resolved_indy_entry_at(i)->check_no_old_or_obsolete_entry()) {
641         log_trace(redefine, class, update, constantpool)
642           ("cpcache check found old method entry: class: %s, old: %d, obsolete: %d, method: %s",
643            constant_pool()->pool_holder()->external_name(), m->is_old(), m->is_obsolete(), m->external_name());
644         return false;
645       }
646     }
647   }
648   if (_resolved_method_entries != nullptr) {
649     for (int i = 0; i < _resolved_method_entries->length(); i++) {
650       ResolvedMethodEntry* method_entry = resolved_method_entry_at(i);
651       Method* m = method_entry->method();
652       if (m != nullptr && !method_entry->check_no_old_or_obsolete_entry()) {
653         log_trace(redefine, class, update, constantpool)
654           ("cpcache check found old method entry: class: %s, old: %d, obsolete: %d, method: %s",
655            constant_pool()->pool_holder()->external_name(), m->is_old(), m->is_obsolete(), m->external_name());
656         return false;
657       }
658     }
659   }
660   return true;
661 }
662 
663 void ConstantPoolCache::dump_cache() {
664   print_on(tty);
665 }
666 #endif // INCLUDE_JVMTI
667 
668 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
669   log_trace(cds)("Iter(ConstantPoolCache): %p", this);
670   it->push(&_constant_pool);
671   it->push(&_reference_map);
672   if (_resolved_indy_entries != nullptr) {
673     it->push(&_resolved_indy_entries, MetaspaceClosure::_writable);
674   }
675   if (_resolved_field_entries != nullptr) {
676     it->push(&_resolved_field_entries, MetaspaceClosure::_writable);
677   }
678   if (_resolved_method_entries != nullptr) {
679     it->push(&_resolved_method_entries, MetaspaceClosure::_writable);
680   }
681 }
682 
683 bool ConstantPoolCache::save_and_throw_indy_exc(
684   const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
685 
686   assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
687   assert(PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass()),
688          "No LinkageError exception");
689 
690   // Use the resolved_references() lock for this cpCache entry.
691   // resolved_references are created for all classes with Invokedynamic, MethodHandle
692   // or MethodType constant pool cache entries.
693   JavaThread* current = THREAD;
694   objArrayHandle resolved_references(current, cpool->resolved_references());
695   assert(resolved_references() != nullptr,
696          "a resolved_references array should have been created for this class");
697   ObjectLocker ol(resolved_references, current);
698 
699   // if the indy_info is resolved or the indy_resolution_failed flag is set then another
700   // thread either succeeded in resolving the method or got a LinkageError
701   // exception, before this thread was able to record its failure.  So, clear
702   // this thread's exception and return false so caller can use the earlier
703   // thread's result.
704   if (resolved_indy_entry_at(index)->is_resolved() || resolved_indy_entry_at(index)->resolution_failed()) {
705     CLEAR_PENDING_EXCEPTION;
706     return false;
707   }
708   ResourceMark rm(THREAD);
709   Symbol* error = PENDING_EXCEPTION->klass()->name();
710   const char* message = java_lang_Throwable::message_as_utf8(PENDING_EXCEPTION);
711 
712   int encoded_index = ResolutionErrorTable::encode_indy_index(index);
713   SystemDictionary::add_resolution_error(cpool, encoded_index, error, message);
714   resolved_indy_entry_at(index)->set_resolution_failed();
715   return true;
716 }
717 
718 oop ConstantPoolCache::set_dynamic_call(const CallInfo &call_info, int index) {
719   ResourceMark rm;
720 
721   // Use the resolved_references() lock for this cpCache entry.
722   // resolved_references are created for all classes with Invokedynamic, MethodHandle
723   // or MethodType constant pool cache entries.
724   JavaThread* current = JavaThread::current();
725   constantPoolHandle cp(current, constant_pool());
726 
727   objArrayHandle resolved_references(current, cp->resolved_references());
728   assert(resolved_references() != nullptr,
729          "a resolved_references array should have been created for this class");
730   ObjectLocker ol(resolved_references, current);
731   assert(index >= 0, "Indy index must be positive at this point");
732 
733   if (resolved_indy_entry_at(index)->method() != nullptr) {
734     return cp->resolved_reference_from_indy(index);
735   }
736 
737   if (resolved_indy_entry_at(index)->resolution_failed()) {
738     // Before we got here, another thread got a LinkageError exception during
739     // resolution.  Ignore our success and throw their exception.
740     guarantee(index >= 0, "Invalid indy index");
741     int encoded_index = ResolutionErrorTable::encode_indy_index(index);
742     ConstantPool::throw_resolution_error(cp, encoded_index, current);
743     return nullptr;
744   }
745 
746   Method* adapter            = call_info.resolved_method();
747   const Handle appendix      = call_info.resolved_appendix();
748   const bool has_appendix    = appendix.not_null();
749 
750   LogStream* log_stream = nullptr;
751   LogStreamHandle(Debug, methodhandles, indy) lsh_indy;
752   if (lsh_indy.is_enabled()) {
753     ResourceMark rm;
754     log_stream = &lsh_indy;
755     log_stream->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ",
756                          0xba,
757                          p2i(appendix()),
758                          (has_appendix ? "" : " (unused)"),
759                          p2i(adapter));
760     adapter->print_on(log_stream);
761     if (has_appendix)  appendix()->print_on(log_stream);
762   }
763 
764   if (has_appendix) {
765     const int appendix_index = resolved_indy_entry_at(index)->resolved_references_index();
766     assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
767     assert(resolved_references->obj_at(appendix_index) == nullptr, "init just once");
768     resolved_references->obj_at_put(appendix_index, appendix());
769   }
770 
771   // Populate entry with resolved information
772   assert(resolved_indy_entries() != nullptr, "Invokedynamic array is empty, cannot fill with resolved information");
773   resolved_indy_entry_at(index)->fill_in(adapter, adapter->size_of_parameters(), as_TosState(adapter->result_type()), has_appendix);
774 
775   if (log_stream != nullptr) {
776     resolved_indy_entry_at(index)->print_on(log_stream);
777   }
778   return appendix();
779 }
780 
781 oop ConstantPoolCache::appendix_if_resolved(int method_index) const {
782   ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
783   return appendix_if_resolved(method_entry);
784 }
785 
786 oop ConstantPoolCache::appendix_if_resolved(ResolvedMethodEntry* method_entry) const {
787   if (!method_entry->has_appendix())
788     return nullptr;
789   const int ref_index = method_entry->resolved_references_index();
790   return constant_pool()->resolved_reference_at(ref_index);
791 }
792 
793 // Printing
794 
795 void ConstantPoolCache::print_on(outputStream* st) const {
796   st->print_cr("%s", internal_name());
797   // print constant pool cache entries
798   print_resolved_field_entries(st);
799   print_resolved_method_entries(st);
800   print_resolved_indy_entries(st);
801 }
802 
803 void ConstantPoolCache::print_resolved_field_entries(outputStream* st) const {
804   for (int field_index = 0; field_index < resolved_field_entries_length(); field_index++) {
805     resolved_field_entry_at(field_index)->print_on(st);
806   }
807 }
808 
809 void ConstantPoolCache::print_resolved_method_entries(outputStream* st) const {
810   for (int method_index = 0; method_index < resolved_method_entries_length(); method_index++) {
811     ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
812     method_entry->print_on(st);
813     if (method_entry->has_appendix()) {
814       st->print("  appendix: ");
815       constant_pool()->resolved_reference_from_method(method_index)->print_on(st);
816     }
817   }
818 }
819 
820 void ConstantPoolCache::print_resolved_indy_entries(outputStream* st) const {
821   for (int indy_index = 0; indy_index < resolved_indy_entries_length(); indy_index++) {
822     ResolvedIndyEntry* indy_entry = resolved_indy_entry_at(indy_index);
823     indy_entry->print_on(st);
824     if (indy_entry->has_appendix()) {
825       st->print("  appendix: ");
826       constant_pool()->resolved_reference_from_indy(indy_index)->print_on(st);
827     }
828   }
829 }