1 /* 2 * Copyright (c) 1998, 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 "classfile/resolutionErrors.hpp" 27 #include "interpreter/bytecodeStream.hpp" 28 #include "interpreter/bytecodes.hpp" 29 #include "interpreter/interpreter.hpp" 30 #include "interpreter/linkResolver.hpp" 31 #include "interpreter/rewriter.hpp" 32 #include "logging/log.hpp" 33 #include "memory/heapShared.hpp" 34 #include "memory/metadataFactory.hpp" 35 #include "memory/metaspaceClosure.hpp" 36 #include "memory/metaspaceShared.hpp" 37 #include "memory/resourceArea.hpp" 38 #include "memory/universe.hpp" 39 #include "oops/access.inline.hpp" 40 #include "oops/constantPool.inline.hpp" 41 #include "oops/cpCache.inline.hpp" 42 #include "oops/objArrayOop.inline.hpp" 43 #include "oops/oop.inline.hpp" 44 #include "prims/methodHandles.hpp" 45 #include "runtime/atomic.hpp" 46 #include "runtime/handles.inline.hpp" 47 #include "runtime/orderAccess.hpp" 48 #include "utilities/macros.hpp" 49 50 // Implementation of ConstantPoolCacheEntry 51 52 void ConstantPoolCacheEntry::initialize_entry(int index) { 53 assert(0 < index && index < 0x10000, "sanity check"); 54 _indices = index; 55 _f1 = NULL; 56 _f2 = _flags = 0; 57 assert(constant_pool_index() == index, ""); 58 } 59 60 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) { 61 assert((_indices & (~cp_index_mask)) == 0, "sanity"); 62 assert(_f1 == NULL, "sanity"); 63 assert(_flags == 0, "sanity"); 64 if (!f2_used) { 65 assert(_f2 == 0, "sanity"); 66 } 67 } 68 69 void ConstantPoolCacheEntry::reinitialize(bool f2_used) { 70 _indices &= cp_index_mask; 71 _f1 = NULL; 72 _flags = 0; 73 if (!f2_used) { 74 _f2 = 0; 75 } 76 } 77 78 int ConstantPoolCacheEntry::make_flags(TosState state, 79 int option_bits, 80 int field_index_or_method_params) { 81 assert(state < number_of_states, "Invalid state in make_flags"); 82 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params; 83 // Preserve existing flag bit values 84 // The low bits are a field offset, or else the method parameter size. 85 #ifdef ASSERT 86 TosState old_state = flag_state(); 87 assert(old_state == (TosState)0 || old_state == state, 88 "inconsistent cpCache flags state"); 89 #endif 90 return (_flags | f) ; 91 } 92 93 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) { 94 #ifdef ASSERT 95 // Read once. 96 volatile Bytecodes::Code c = bytecode_1(); 97 assert(c == 0 || c == code || code == 0, "update must be consistent"); 98 #endif 99 // Need to flush pending stores here before bytecode is written. 100 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift)); 101 } 102 103 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) { 104 #ifdef ASSERT 105 // Read once. 106 volatile Bytecodes::Code c = bytecode_2(); 107 assert(c == 0 || c == code || code == 0, "update must be consistent"); 108 #endif 109 // Need to flush pending stores here before bytecode is written. 110 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift)); 111 } 112 113 // Sets f1, ordering with previous writes. 114 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) { 115 assert(f1 != NULL, ""); 116 OrderAccess::release_store(&_f1, f1); 117 } 118 119 void ConstantPoolCacheEntry::set_indy_resolution_failed() { 120 OrderAccess::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift)); 121 } 122 123 // Note that concurrent update of both bytecodes can leave one of them 124 // reset to zero. This is harmless; the interpreter will simply re-resolve 125 // the damaged entry. More seriously, the memory synchronization is needed 126 // to flush other fields (f1, f2) completely to memory before the bytecodes 127 // are updated, lest other processors see a non-zero bytecode but zero f1/f2. 128 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code, 129 Bytecodes::Code put_code, 130 Klass* field_holder, 131 int field_index, 132 int field_offset, 133 TosState field_type, 134 bool is_final, 135 bool is_volatile, 136 Klass* root_klass) { 137 set_f1(field_holder); 138 set_f2(field_offset); 139 assert((field_index & field_index_mask) == field_index, 140 "field index does not fit in low flag bits"); 141 set_field_flags(field_type, 142 ((is_volatile ? 1 : 0) << is_volatile_shift) | 143 ((is_final ? 1 : 0) << is_final_shift), 144 field_index); 145 set_bytecode_1(get_code); 146 set_bytecode_2(put_code); 147 NOT_PRODUCT(verify(tty)); 148 } 149 150 void ConstantPoolCacheEntry::set_parameter_size(int value) { 151 // This routine is called only in corner cases where the CPCE is not yet initialized. 152 // See AbstractInterpreter::deopt_continue_after_entry. 153 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value, 154 "size must not change: parameter_size=%d, value=%d", parameter_size(), value); 155 // Setting the parameter size by itself is only safe if the 156 // current value of _flags is 0, otherwise another thread may have 157 // updated it and we don't want to overwrite that value. Don't 158 // bother trying to update it once it's nonzero but always make 159 // sure that the final parameter size agrees with what was passed. 160 if (_flags == 0) { 161 intx newflags = (value & parameter_size_mask); 162 Atomic::cmpxchg(newflags, &_flags, (intx)0); 163 } 164 guarantee(parameter_size() == value, 165 "size must not change: parameter_size=%d, value=%d", parameter_size(), value); 166 } 167 168 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code, 169 const methodHandle& method, 170 int vtable_index, 171 bool sender_is_interface, 172 InstanceKlass* pool_holder) { 173 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean 174 assert(method->interpreter_entry() != NULL, "should have been set at this point"); 175 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache"); 176 177 int byte_no = -1; 178 bool change_to_virtual = false; 179 InstanceKlass* holder = NULL; // have to declare this outside the switch 180 switch (invoke_code) { 181 case Bytecodes::_invokeinterface: 182 holder = method->method_holder(); 183 // check for private interface method invocations 184 if (vtable_index == Method::nonvirtual_vtable_index && holder->is_interface() ) { 185 assert(method->is_private(), "unexpected non-private method"); 186 assert(method->can_be_statically_bound(), "unexpected non-statically-bound method"); 187 // set_f2_as_vfinal_method checks if is_vfinal flag is true. 188 set_method_flags(as_TosState(method->result_type()), 189 ( 1 << is_vfinal_shift) | 190 ((method->is_final_method() ? 1 : 0) << is_final_shift), 191 method()->size_of_parameters()); 192 set_f2_as_vfinal_method(method()); 193 byte_no = 2; 194 set_f1(holder); // interface klass* 195 break; 196 } 197 else { 198 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface 199 // instruction links to a non-interface method (in Object). This can happen when 200 // an interface redeclares an Object method (like CharSequence declaring toString()) 201 // or when invokeinterface is used explicitly. 202 // In that case, the method has no itable index and must be invoked as a virtual. 203 // Set a flag to keep track of this corner case. 204 assert(holder->is_interface() || holder == SystemDictionary::Object_klass(), "unexpected holder class"); 205 assert(method->is_public(), "Calling non-public method in Object with invokeinterface"); 206 change_to_virtual = true; 207 208 // ...and fall through as if we were handling invokevirtual: 209 } 210 case Bytecodes::_invokevirtual: 211 { 212 if (!is_vtable_call) { 213 assert(method->can_be_statically_bound(), ""); 214 // set_f2_as_vfinal_method checks if is_vfinal flag is true. 215 set_method_flags(as_TosState(method->result_type()), 216 ( 1 << is_vfinal_shift) | 217 ((method->is_final_method() ? 1 : 0) << is_final_shift) | 218 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift), 219 method()->size_of_parameters()); 220 set_f2_as_vfinal_method(method()); 221 } else { 222 assert(!method->can_be_statically_bound(), ""); 223 assert(vtable_index >= 0, "valid index"); 224 assert(!method->is_final_method(), "sanity"); 225 set_method_flags(as_TosState(method->result_type()), 226 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift), 227 method()->size_of_parameters()); 228 set_f2(vtable_index); 229 } 230 byte_no = 2; 231 break; 232 } 233 234 case Bytecodes::_invokespecial: 235 case Bytecodes::_invokestatic: 236 assert(!is_vtable_call, ""); 237 // Note: Read and preserve the value of the is_vfinal flag on any 238 // invokevirtual bytecode shared with this constant pool cache entry. 239 // It is cheap and safe to consult is_vfinal() at all times. 240 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop. 241 set_method_flags(as_TosState(method->result_type()), 242 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) | 243 ((method->is_final_method() ? 1 : 0) << is_final_shift), 244 method()->size_of_parameters()); 245 set_f1(method()); 246 byte_no = 1; 247 break; 248 default: 249 ShouldNotReachHere(); 250 break; 251 } 252 253 // Note: byte_no also appears in TemplateTable::resolve. 254 if (byte_no == 1) { 255 assert(invoke_code != Bytecodes::_invokevirtual && 256 invoke_code != Bytecodes::_invokeinterface, ""); 257 bool do_resolve = true; 258 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver 259 // has to be checked that it is a subclass of the current class every time this bytecode 260 // is executed. 261 if (invoke_code == Bytecodes::_invokespecial && sender_is_interface && 262 method->name() != vmSymbols::object_initializer_name()) { 263 do_resolve = false; 264 } 265 // Don't mark invokestatic to method as resolved if the holder class has not yet completed 266 // initialization. An invokestatic must only proceed if the class is initialized, but if 267 // we resolve it before then that class initialization check is skipped. However if the call 268 // is from the same class we can resolve as we must be executing with <clinit> on our call stack. 269 if (invoke_code == Bytecodes::_invokestatic && 270 !method->method_holder()->is_initialized() && 271 method->method_holder() != pool_holder) { 272 do_resolve = false; 273 } 274 if (do_resolve) { 275 assert(method->method_holder()->is_initialized() || 276 method->method_holder()->is_reentrant_initialization(Thread::current()), 277 "invalid class initalization state"); 278 set_bytecode_1(invoke_code); 279 } 280 } else if (byte_no == 2) { 281 if (change_to_virtual) { 282 assert(invoke_code == Bytecodes::_invokeinterface, ""); 283 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!! 284 // 285 // Workaround for the case where we encounter an invokeinterface, but we 286 // should really have an _invokevirtual since the resolved method is a 287 // virtual method in java.lang.Object. This is a corner case in the spec 288 // but is presumably legal. javac does not generate this code. 289 // 290 // We do not set bytecode_1() to _invokeinterface, because that is the 291 // bytecode # used by the interpreter to see if it is resolved. In this 292 // case, the method gets reresolved with caller for each interface call 293 // because the actual selected method may not be public. 294 // 295 // We set bytecode_2() to _invokevirtual. 296 // See also interpreterRuntime.cpp. (8/25/2000) 297 } else { 298 assert(invoke_code == Bytecodes::_invokevirtual || 299 (invoke_code == Bytecodes::_invokeinterface && 300 ((method->is_private() || 301 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))), 302 "unexpected invocation mode"); 303 if (invoke_code == Bytecodes::_invokeinterface && 304 (method->is_private() || method->is_final())) { 305 // We set bytecode_1() to _invokeinterface, because that is the 306 // bytecode # used by the interpreter to see if it is resolved. 307 // We set bytecode_2() to _invokevirtual. 308 set_bytecode_1(invoke_code); 309 } 310 } 311 // set up for invokevirtual, even if linking for invokeinterface also: 312 set_bytecode_2(Bytecodes::_invokevirtual); 313 } else { 314 ShouldNotReachHere(); 315 } 316 NOT_PRODUCT(verify(tty)); 317 } 318 319 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method, 320 bool sender_is_interface, InstanceKlass* pool_holder) { 321 int index = Method::nonvirtual_vtable_index; 322 // index < 0; FIXME: inline and customize set_direct_or_vtable_call 323 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface, pool_holder); 324 } 325 326 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) { 327 // either the method is a miranda or its holder should accept the given index 328 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), ""); 329 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call 330 set_direct_or_vtable_call(invoke_code, method, index, false, NULL /* not used */); 331 } 332 333 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, 334 Klass* referenced_klass, 335 const methodHandle& method, int index) { 336 assert(method->method_holder()->verify_itable_index(index), ""); 337 assert(invoke_code == Bytecodes::_invokeinterface, ""); 338 InstanceKlass* interf = method->method_holder(); 339 assert(interf->is_interface(), "must be an interface"); 340 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here"); 341 set_f1(referenced_klass); 342 set_f2((intx)method()); 343 set_method_flags(as_TosState(method->result_type()), 344 0, // no option bits 345 method()->size_of_parameters()); 346 set_bytecode_1(Bytecodes::_invokeinterface); 347 } 348 349 350 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) { 351 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info); 352 } 353 354 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) { 355 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info); 356 } 357 358 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool, 359 Bytecodes::Code invoke_code, 360 const CallInfo &call_info) { 361 // NOTE: This CPCE can be the subject of data races. 362 // There are three words to update: flags, refs[f2], f1 (in that order). 363 // Writers must store all other values before f1. 364 // Readers must test f1 first for non-null before reading other fields. 365 // Competing writers must acquire exclusive access via a lock. 366 // A losing writer waits on the lock until the winner writes f1 and leaves 367 // the lock, so that when the losing writer returns, he can use the linked 368 // cache entry. 369 370 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 371 // Use the resolved_references() lock for this cpCache entry. 372 // resolved_references are created for all classes with Invokedynamic, MethodHandle 373 // or MethodType constant pool cache entries. 374 assert(resolved_references() != NULL, 375 "a resolved_references array should have been created for this class"); 376 ObjectLocker ol(resolved_references, Thread::current()); 377 if (!is_f1_null()) { 378 return; 379 } 380 381 if (indy_resolution_failed()) { 382 // Before we got here, another thread got a LinkageError exception during 383 // resolution. Ignore our success and throw their exception. 384 ConstantPoolCache* cpCache = cpool->cache(); 385 int index = -1; 386 for (int i = 0; i < cpCache->length(); i++) { 387 if (cpCache->entry_at(i) == this) { 388 index = i; 389 break; 390 } 391 } 392 guarantee(index >= 0, "Didn't find cpCache entry!"); 393 int encoded_index = ResolutionErrorTable::encode_cpcache_index( 394 ConstantPool::encode_invokedynamic_index(index)); 395 Thread* THREAD = Thread::current(); 396 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD); 397 return; 398 } 399 400 const methodHandle adapter = call_info.resolved_method(); 401 const Handle appendix = call_info.resolved_appendix(); 402 const bool has_appendix = appendix.not_null(); 403 404 // Write the flags. 405 // MHs and indy are always sig-poly and have a local signature. 406 set_method_flags(as_TosState(adapter->result_type()), 407 ((has_appendix ? 1 : 0) << has_appendix_shift ) | 408 ( 1 << has_local_signature_shift ) | 409 ( 1 << is_final_shift ), 410 adapter->size_of_parameters()); 411 412 if (TraceInvokeDynamic) { 413 ttyLocker ttyl; 414 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ", 415 invoke_code, 416 p2i(appendix()), 417 (has_appendix ? "" : " (unused)"), 418 p2i(adapter())); 419 adapter->print(); 420 if (has_appendix) appendix()->print(); 421 } 422 423 // Method handle invokes and invokedynamic sites use both cp cache words. 424 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter. 425 // In the general case, this could be the call site's MethodType, 426 // for use with java.lang.Invokers.checkExactType, or else a CallSite object. 427 // f1 contains the adapter method which manages the actual call. 428 // In the general case, this is a compiled LambdaForm. 429 // (The Java code is free to optimize these calls by binding other 430 // sorts of methods and appendices to call sites.) 431 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased. 432 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits. 433 // Even with the appendix, the method will never take more than 255 parameter slots. 434 // 435 // This means that given a call site like (List)mh.invoke("foo"), 436 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;', 437 // not '(Ljava/lang/String;)Ljava/util/List;'. 438 // The fact that String and List are involved is encoded in the MethodType in refs[f2]. 439 // This allows us to create fewer Methods, while keeping type safety. 440 // 441 442 // Store appendix, if any. 443 if (has_appendix) { 444 const int appendix_index = f2_as_index(); 445 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob"); 446 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once"); 447 resolved_references->obj_at_put(appendix_index, appendix()); 448 } 449 450 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)! 451 452 // The interpreter assembly code does not check byte_2, 453 // but it is used by is_resolved, method_if_resolved, etc. 454 set_bytecode_1(invoke_code); 455 NOT_PRODUCT(verify(tty)); 456 if (TraceInvokeDynamic) { 457 ttyLocker ttyl; 458 this->print(tty, 0); 459 } 460 461 assert(has_appendix == this->has_appendix(), "proper storage of appendix flag"); 462 assert(this->has_local_signature(), "proper storage of signature flag"); 463 } 464 465 bool ConstantPoolCacheEntry::save_and_throw_indy_exc( 466 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) { 467 468 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!"); 469 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()), 470 "No LinkageError exception"); 471 472 // Use the resolved_references() lock for this cpCache entry. 473 // resolved_references are created for all classes with Invokedynamic, MethodHandle 474 // or MethodType constant pool cache entries. 475 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 476 assert(resolved_references() != NULL, 477 "a resolved_references array should have been created for this class"); 478 ObjectLocker ol(resolved_references, THREAD); 479 480 // if f1 is not null or the indy_resolution_failed flag is set then another 481 // thread either succeeded in resolving the method or got a LinkageError 482 // exception, before this thread was able to record its failure. So, clear 483 // this thread's exception and return false so caller can use the earlier 484 // thread's result. 485 if (!is_f1_null() || indy_resolution_failed()) { 486 CLEAR_PENDING_EXCEPTION; 487 return false; 488 } 489 490 Symbol* error = PENDING_EXCEPTION->klass()->name(); 491 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION); 492 493 SystemDictionary::add_resolution_error(cpool, index, error, message); 494 set_indy_resolution_failed(); 495 return true; 496 } 497 498 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) { 499 // Decode the action of set_method and set_interface_call 500 Bytecodes::Code invoke_code = bytecode_1(); 501 if (invoke_code != (Bytecodes::Code)0) { 502 Metadata* f1 = f1_ord(); 503 if (f1 != NULL) { 504 switch (invoke_code) { 505 case Bytecodes::_invokeinterface: 506 assert(f1->is_klass(), ""); 507 return klassItable::method_for_itable_index((InstanceKlass*)f1, f2_as_index()); 508 case Bytecodes::_invokestatic: 509 case Bytecodes::_invokespecial: 510 assert(!has_appendix(), ""); 511 case Bytecodes::_invokehandle: 512 case Bytecodes::_invokedynamic: 513 assert(f1->is_method(), ""); 514 return (Method*)f1; 515 default: 516 break; 517 } 518 } 519 } 520 invoke_code = bytecode_2(); 521 if (invoke_code != (Bytecodes::Code)0) { 522 switch (invoke_code) { 523 case Bytecodes::_invokevirtual: 524 if (is_vfinal()) { 525 // invokevirtual 526 Method* m = f2_as_vfinal_method(); 527 assert(m->is_method(), ""); 528 return m; 529 } else { 530 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index()); 531 if (cpool->tag_at(holder_index).is_klass()) { 532 Klass* klass = cpool->resolved_klass_at(holder_index); 533 return klass->method_at_vtable(f2_as_index()); 534 } 535 } 536 break; 537 default: 538 break; 539 } 540 } 541 return NULL; 542 } 543 544 545 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) { 546 if (!has_appendix()) 547 return NULL; 548 const int ref_index = f2_as_index(); 549 objArrayOop resolved_references = cpool->resolved_references(); 550 return resolved_references->obj_at(ref_index); 551 } 552 553 554 #if INCLUDE_JVMTI 555 556 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) { 557 if (log_is_enabled(Info, redefine, class, update)) { 558 ResourceMark rm; 559 if (!(*trace_name_printed)) { 560 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name()); 561 *trace_name_printed = true; 562 } 563 log_debug(redefine, class, update, constantpool) 564 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 565 } 566 } 567 568 // RedefineClasses() API support: 569 // If this ConstantPoolCacheEntry refers to old_method then update it 570 // to refer to new_method. 571 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method, 572 Method* new_method, bool * trace_name_printed) { 573 574 if (is_vfinal()) { 575 // virtual and final so _f2 contains method ptr instead of vtable index 576 if (f2_as_vfinal_method() == old_method) { 577 // match old_method so need an update 578 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values 579 _f2 = (intptr_t)new_method; 580 log_adjust("vfinal", old_method, new_method, trace_name_printed); 581 } 582 return; 583 } 584 585 assert (_f1 != NULL, "should not call with uninteresting entry"); 586 587 if (!(_f1->is_method())) { 588 // _f1 is a Klass* for an interface, _f2 is the method 589 if (f2_as_interface_method() == old_method) { 590 _f2 = (intptr_t)new_method; 591 log_adjust("interface", old_method, new_method, trace_name_printed); 592 } 593 } else if (_f1 == old_method) { 594 _f1 = new_method; 595 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed); 596 } 597 } 598 599 // a constant pool cache entry should never contain old or obsolete methods 600 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() { 601 Method* m = get_interesting_method_entry(); 602 // return false if m refers to a non-deleted old or obsolete method 603 if (m != NULL) { 604 assert(m->is_valid() && m->is_method(), "m is a valid method"); 605 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete 606 } else { 607 return true; 608 } 609 } 610 611 Method* ConstantPoolCacheEntry::get_interesting_method_entry() { 612 if (!is_method_entry()) { 613 // not a method entry so not interesting by default 614 return NULL; 615 } 616 Method* m = NULL; 617 if (is_vfinal()) { 618 // virtual and final so _f2 contains method ptr instead of vtable index 619 m = f2_as_vfinal_method(); 620 } else if (is_f1_null()) { 621 // NULL _f1 means this is a virtual entry so also not interesting 622 return NULL; 623 } else { 624 if (!(_f1->is_method())) { 625 // _f1 is a Klass* for an interface 626 m = f2_as_interface_method(); 627 } else { 628 m = f1_as_method(); 629 } 630 } 631 assert(m != NULL && m->is_method(), "sanity check"); 632 if (m == NULL || !m->is_method()) { 633 return NULL; 634 } 635 return m; 636 } 637 #endif // INCLUDE_JVMTI 638 639 void ConstantPoolCacheEntry::print(outputStream* st, int index) const { 640 // print separator 641 if (index == 0) st->print_cr(" -------------"); 642 // print entry 643 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this); 644 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), 645 constant_pool_index()); 646 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1); 647 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2); 648 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags); 649 st->print_cr(" -------------"); 650 } 651 652 void ConstantPoolCacheEntry::verify(outputStream* st) const { 653 // not implemented yet 654 } 655 656 // Implementation of ConstantPoolCache 657 658 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data, 659 const intStack& index_map, 660 const intStack& invokedynamic_index_map, 661 const intStack& invokedynamic_map, TRAPS) { 662 663 const int length = index_map.length() + invokedynamic_index_map.length(); 664 int size = ConstantPoolCache::size(length); 665 666 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD) 667 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map); 668 } 669 670 void ConstantPoolCache::initialize(const intArray& inverse_index_map, 671 const intArray& invokedynamic_inverse_index_map, 672 const intArray& invokedynamic_references_map) { 673 for (int i = 0; i < inverse_index_map.length(); i++) { 674 ConstantPoolCacheEntry* e = entry_at(i); 675 int original_index = inverse_index_map.at(i); 676 e->initialize_entry(original_index); 677 assert(entry_at(i) == e, "sanity"); 678 } 679 680 // Append invokedynamic entries at the end 681 int invokedynamic_offset = inverse_index_map.length(); 682 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) { 683 int offset = i + invokedynamic_offset; 684 ConstantPoolCacheEntry* e = entry_at(offset); 685 int original_index = invokedynamic_inverse_index_map.at(i); 686 e->initialize_entry(original_index); 687 assert(entry_at(offset) == e, "sanity"); 688 } 689 690 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) { 691 const int cpci = invokedynamic_references_map.at(ref); 692 if (cpci >= 0) { 693 entry_at(cpci)->initialize_resolved_reference_index(ref); 694 } 695 } 696 } 697 698 void ConstantPoolCache::verify_just_initialized() { 699 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true)); 700 } 701 702 void ConstantPoolCache::remove_unshareable_info() { 703 walk_entries_for_initialization(/*check_only = */ false); 704 } 705 706 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) { 707 assert(DumpSharedSpaces, "sanity"); 708 // When dumping the archive, we want to clean up the ConstantPoolCache 709 // to remove any effect of linking due to the execution of Java code -- 710 // each ConstantPoolCacheEntry will have the same contents as if 711 // ConstantPoolCache::initialize has just returned: 712 // 713 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries. 714 // - We keep the "f2" field for entries used by invokedynamic and invokehandle 715 // - All other bits in the entries are cleared to zero. 716 ResourceMark rm; 717 718 InstanceKlass* ik = constant_pool()->pool_holder(); 719 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length()); 720 memset(f2_used, 0, sizeof(bool) * length()); 721 722 // Find all the slots that we need to preserve f2 723 for (int i = 0; i < ik->methods()->length(); i++) { 724 Method* m = ik->methods()->at(i); 725 RawBytecodeStream bcs(m); 726 while (!bcs.is_last_bytecode()) { 727 Bytecodes::Code opcode = bcs.raw_next(); 728 switch (opcode) { 729 case Bytecodes::_invokedynamic: { 730 int index = Bytes::get_native_u4(bcs.bcp() + 1); 731 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index); 732 f2_used[cp_cache_index] = 1; 733 } 734 break; 735 case Bytecodes::_invokehandle: { 736 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1); 737 f2_used[cp_cache_index] = 1; 738 } 739 break; 740 default: 741 break; 742 } 743 } 744 } 745 746 if (check_only) { 747 DEBUG_ONLY( 748 for (int i=0; i<length(); i++) { 749 entry_at(i)->verify_just_initialized(f2_used[i]); 750 }) 751 } else { 752 for (int i=0; i<length(); i++) { 753 entry_at(i)->reinitialize(f2_used[i]); 754 } 755 } 756 } 757 758 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) { 759 assert(!is_shared(), "shared caches are not deallocated"); 760 data->remove_handle(_resolved_references); 761 set_resolved_references(NULL); 762 MetadataFactory::free_array<u2>(data, _reference_map); 763 set_reference_map(NULL); 764 } 765 766 #if INCLUDE_CDS_JAVA_HEAP 767 oop ConstantPoolCache::archived_references() { 768 if (CompressedOops::is_null(_archived_references)) { 769 return NULL; 770 } 771 return HeapShared::materialize_archived_object(_archived_references); 772 } 773 774 void ConstantPoolCache::set_archived_references(oop o) { 775 assert(DumpSharedSpaces, "called only during runtime"); 776 _archived_references = CompressedOops::encode(o); 777 } 778 #endif 779 780 #if INCLUDE_JVMTI 781 // RedefineClasses() API support: 782 // If any entry of this ConstantPoolCache points to any of 783 // old_methods, replace it with the corresponding new_method. 784 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) { 785 for (int i = 0; i < length(); i++) { 786 ConstantPoolCacheEntry* entry = entry_at(i); 787 Method* old_method = entry->get_interesting_method_entry(); 788 if (old_method == NULL || !old_method->is_old()) { 789 continue; // skip uninteresting entries 790 } 791 if (old_method->is_deleted()) { 792 // clean up entries with deleted methods 793 entry->initialize_entry(entry->constant_pool_index()); 794 continue; 795 } 796 Method* new_method = old_method->get_new_method(); 797 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed); 798 } 799 } 800 801 // the constant pool cache should never contain old or obsolete methods 802 bool ConstantPoolCache::check_no_old_or_obsolete_entries() { 803 for (int i = 1; i < length(); i++) { 804 if (entry_at(i)->get_interesting_method_entry() != NULL && 805 !entry_at(i)->check_no_old_or_obsolete_entries()) { 806 return false; 807 } 808 } 809 return true; 810 } 811 812 void ConstantPoolCache::dump_cache() { 813 for (int i = 1; i < length(); i++) { 814 if (entry_at(i)->get_interesting_method_entry() != NULL) { 815 entry_at(i)->print(tty, i); 816 } 817 } 818 } 819 #endif // INCLUDE_JVMTI 820 821 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) { 822 log_trace(cds)("Iter(ConstantPoolCache): %p", this); 823 it->push(&_constant_pool); 824 it->push(&_reference_map); 825 } 826 827 // Printing 828 829 void ConstantPoolCache::print_on(outputStream* st) const { 830 st->print_cr("%s", internal_name()); 831 // print constant pool cache entries 832 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i); 833 } 834 835 void ConstantPoolCache::print_value_on(outputStream* st) const { 836 st->print("cache [%d]", length()); 837 print_address_on(st); 838 st->print(" for "); 839 constant_pool()->print_value_on(st); 840 } 841 842 843 // Verification 844 845 void ConstantPoolCache::verify_on(outputStream* st) { 846 // print constant pool cache entries 847 for (int i = 0; i < length(); i++) entry_at(i)->verify(st); 848 }