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 if (!method->method_holder()->is_initialized() && 271 method->method_holder() != pool_holder) { 272 do_resolve = false; 273 } else { 274 assert(method->method_holder()->is_initialized() || 275 method->method_holder()->is_reentrant_initialization(Thread::current()), 276 "invalid class initialization state for invoke_static"); 277 } 278 } 279 if (do_resolve) { 280 set_bytecode_1(invoke_code); 281 } 282 } else if (byte_no == 2) { 283 if (change_to_virtual) { 284 assert(invoke_code == Bytecodes::_invokeinterface, ""); 285 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!! 286 // 287 // Workaround for the case where we encounter an invokeinterface, but we 288 // should really have an _invokevirtual since the resolved method is a 289 // virtual method in java.lang.Object. This is a corner case in the spec 290 // but is presumably legal. javac does not generate this code. 291 // 292 // We do not set bytecode_1() to _invokeinterface, because that is the 293 // bytecode # used by the interpreter to see if it is resolved. In this 294 // case, the method gets reresolved with caller for each interface call 295 // because the actual selected method may not be public. 296 // 297 // We set bytecode_2() to _invokevirtual. 298 // See also interpreterRuntime.cpp. (8/25/2000) 299 } else { 300 assert(invoke_code == Bytecodes::_invokevirtual || 301 (invoke_code == Bytecodes::_invokeinterface && 302 ((method->is_private() || 303 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))), 304 "unexpected invocation mode"); 305 if (invoke_code == Bytecodes::_invokeinterface && 306 (method->is_private() || method->is_final())) { 307 // We set bytecode_1() to _invokeinterface, because that is the 308 // bytecode # used by the interpreter to see if it is resolved. 309 // We set bytecode_2() to _invokevirtual. 310 set_bytecode_1(invoke_code); 311 } 312 } 313 // set up for invokevirtual, even if linking for invokeinterface also: 314 set_bytecode_2(Bytecodes::_invokevirtual); 315 } else { 316 ShouldNotReachHere(); 317 } 318 NOT_PRODUCT(verify(tty)); 319 } 320 321 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method, 322 bool sender_is_interface, InstanceKlass* pool_holder) { 323 int index = Method::nonvirtual_vtable_index; 324 // index < 0; FIXME: inline and customize set_direct_or_vtable_call 325 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface, pool_holder); 326 } 327 328 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) { 329 // either the method is a miranda or its holder should accept the given index 330 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), ""); 331 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call 332 set_direct_or_vtable_call(invoke_code, method, index, false, NULL /* not used */); 333 } 334 335 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, 336 Klass* referenced_klass, 337 const methodHandle& method, int index) { 338 assert(method->method_holder()->verify_itable_index(index), ""); 339 assert(invoke_code == Bytecodes::_invokeinterface, ""); 340 InstanceKlass* interf = method->method_holder(); 341 assert(interf->is_interface(), "must be an interface"); 342 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here"); 343 set_f1(referenced_klass); 344 set_f2((intx)method()); 345 set_method_flags(as_TosState(method->result_type()), 346 0, // no option bits 347 method()->size_of_parameters()); 348 set_bytecode_1(Bytecodes::_invokeinterface); 349 } 350 351 352 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) { 353 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info); 354 } 355 356 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) { 357 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info); 358 } 359 360 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool, 361 Bytecodes::Code invoke_code, 362 const CallInfo &call_info) { 363 // NOTE: This CPCE can be the subject of data races. 364 // There are three words to update: flags, refs[f2], f1 (in that order). 365 // Writers must store all other values before f1. 366 // Readers must test f1 first for non-null before reading other fields. 367 // Competing writers must acquire exclusive access via a lock. 368 // A losing writer waits on the lock until the winner writes f1 and leaves 369 // the lock, so that when the losing writer returns, he can use the linked 370 // cache entry. 371 372 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 373 // Use the resolved_references() lock for this cpCache entry. 374 // resolved_references are created for all classes with Invokedynamic, MethodHandle 375 // or MethodType constant pool cache entries. 376 assert(resolved_references() != NULL, 377 "a resolved_references array should have been created for this class"); 378 ObjectLocker ol(resolved_references, Thread::current()); 379 if (!is_f1_null()) { 380 return; 381 } 382 383 if (indy_resolution_failed()) { 384 // Before we got here, another thread got a LinkageError exception during 385 // resolution. Ignore our success and throw their exception. 386 ConstantPoolCache* cpCache = cpool->cache(); 387 int index = -1; 388 for (int i = 0; i < cpCache->length(); i++) { 389 if (cpCache->entry_at(i) == this) { 390 index = i; 391 break; 392 } 393 } 394 guarantee(index >= 0, "Didn't find cpCache entry!"); 395 int encoded_index = ResolutionErrorTable::encode_cpcache_index( 396 ConstantPool::encode_invokedynamic_index(index)); 397 Thread* THREAD = Thread::current(); 398 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD); 399 return; 400 } 401 402 const methodHandle adapter = call_info.resolved_method(); 403 const Handle appendix = call_info.resolved_appendix(); 404 const bool has_appendix = appendix.not_null(); 405 406 // Write the flags. 407 // MHs and indy are always sig-poly and have a local signature. 408 set_method_flags(as_TosState(adapter->result_type()), 409 ((has_appendix ? 1 : 0) << has_appendix_shift ) | 410 ( 1 << has_local_signature_shift ) | 411 ( 1 << is_final_shift ), 412 adapter->size_of_parameters()); 413 414 if (TraceInvokeDynamic) { 415 ttyLocker ttyl; 416 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ", 417 invoke_code, 418 p2i(appendix()), 419 (has_appendix ? "" : " (unused)"), 420 p2i(adapter())); 421 adapter->print(); 422 if (has_appendix) appendix()->print(); 423 } 424 425 // Method handle invokes and invokedynamic sites use both cp cache words. 426 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter. 427 // In the general case, this could be the call site's MethodType, 428 // for use with java.lang.Invokers.checkExactType, or else a CallSite object. 429 // f1 contains the adapter method which manages the actual call. 430 // In the general case, this is a compiled LambdaForm. 431 // (The Java code is free to optimize these calls by binding other 432 // sorts of methods and appendices to call sites.) 433 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased. 434 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits. 435 // Even with the appendix, the method will never take more than 255 parameter slots. 436 // 437 // This means that given a call site like (List)mh.invoke("foo"), 438 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;', 439 // not '(Ljava/lang/String;)Ljava/util/List;'. 440 // The fact that String and List are involved is encoded in the MethodType in refs[f2]. 441 // This allows us to create fewer Methods, while keeping type safety. 442 // 443 444 // Store appendix, if any. 445 if (has_appendix) { 446 const int appendix_index = f2_as_index(); 447 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob"); 448 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once"); 449 resolved_references->obj_at_put(appendix_index, appendix()); 450 } 451 452 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)! 453 454 // The interpreter assembly code does not check byte_2, 455 // but it is used by is_resolved, method_if_resolved, etc. 456 set_bytecode_1(invoke_code); 457 NOT_PRODUCT(verify(tty)); 458 if (TraceInvokeDynamic) { 459 ttyLocker ttyl; 460 this->print(tty, 0); 461 } 462 463 assert(has_appendix == this->has_appendix(), "proper storage of appendix flag"); 464 assert(this->has_local_signature(), "proper storage of signature flag"); 465 } 466 467 bool ConstantPoolCacheEntry::save_and_throw_indy_exc( 468 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) { 469 470 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!"); 471 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()), 472 "No LinkageError exception"); 473 474 // Use the resolved_references() lock for this cpCache entry. 475 // resolved_references are created for all classes with Invokedynamic, MethodHandle 476 // or MethodType constant pool cache entries. 477 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 478 assert(resolved_references() != NULL, 479 "a resolved_references array should have been created for this class"); 480 ObjectLocker ol(resolved_references, THREAD); 481 482 // if f1 is not null or the indy_resolution_failed flag is set then another 483 // thread either succeeded in resolving the method or got a LinkageError 484 // exception, before this thread was able to record its failure. So, clear 485 // this thread's exception and return false so caller can use the earlier 486 // thread's result. 487 if (!is_f1_null() || indy_resolution_failed()) { 488 CLEAR_PENDING_EXCEPTION; 489 return false; 490 } 491 492 Symbol* error = PENDING_EXCEPTION->klass()->name(); 493 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION); 494 495 SystemDictionary::add_resolution_error(cpool, index, error, message); 496 set_indy_resolution_failed(); 497 return true; 498 } 499 500 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) { 501 // Decode the action of set_method and set_interface_call 502 Bytecodes::Code invoke_code = bytecode_1(); 503 if (invoke_code != (Bytecodes::Code)0) { 504 Metadata* f1 = f1_ord(); 505 if (f1 != NULL) { 506 switch (invoke_code) { 507 case Bytecodes::_invokeinterface: 508 assert(f1->is_klass(), ""); 509 return f2_as_interface_method(); 510 case Bytecodes::_invokestatic: 511 case Bytecodes::_invokespecial: 512 assert(!has_appendix(), ""); 513 case Bytecodes::_invokehandle: 514 case Bytecodes::_invokedynamic: 515 assert(f1->is_method(), ""); 516 return (Method*)f1; 517 default: 518 break; 519 } 520 } 521 } 522 invoke_code = bytecode_2(); 523 if (invoke_code != (Bytecodes::Code)0) { 524 switch (invoke_code) { 525 case Bytecodes::_invokevirtual: 526 if (is_vfinal()) { 527 // invokevirtual 528 Method* m = f2_as_vfinal_method(); 529 assert(m->is_method(), ""); 530 return m; 531 } else { 532 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index()); 533 if (cpool->tag_at(holder_index).is_klass()) { 534 Klass* klass = cpool->resolved_klass_at(holder_index); 535 return klass->method_at_vtable(f2_as_index()); 536 } 537 } 538 break; 539 default: 540 break; 541 } 542 } 543 return NULL; 544 } 545 546 547 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) { 548 if (!has_appendix()) 549 return NULL; 550 const int ref_index = f2_as_index(); 551 objArrayOop resolved_references = cpool->resolved_references(); 552 return resolved_references->obj_at(ref_index); 553 } 554 555 556 #if INCLUDE_JVMTI 557 558 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) { 559 if (log_is_enabled(Info, redefine, class, update)) { 560 ResourceMark rm; 561 if (!(*trace_name_printed)) { 562 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name()); 563 *trace_name_printed = true; 564 } 565 log_debug(redefine, class, update, constantpool) 566 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 567 } 568 } 569 570 // RedefineClasses() API support: 571 // If this ConstantPoolCacheEntry refers to old_method then update it 572 // to refer to new_method. 573 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method, 574 Method* new_method, bool * trace_name_printed) { 575 576 if (is_vfinal()) { 577 // virtual and final so _f2 contains method ptr instead of vtable index 578 if (f2_as_vfinal_method() == old_method) { 579 // match old_method so need an update 580 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values 581 _f2 = (intptr_t)new_method; 582 log_adjust("vfinal", old_method, new_method, trace_name_printed); 583 } 584 return; 585 } 586 587 assert (_f1 != NULL, "should not call with uninteresting entry"); 588 589 if (!(_f1->is_method())) { 590 // _f1 is a Klass* for an interface, _f2 is the method 591 if (f2_as_interface_method() == old_method) { 592 _f2 = (intptr_t)new_method; 593 log_adjust("interface", old_method, new_method, trace_name_printed); 594 } 595 } else if (_f1 == old_method) { 596 _f1 = new_method; 597 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed); 598 } 599 } 600 601 // a constant pool cache entry should never contain old or obsolete methods 602 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() { 603 Method* m = get_interesting_method_entry(); 604 // return false if m refers to a non-deleted old or obsolete method 605 if (m != NULL) { 606 assert(m->is_valid() && m->is_method(), "m is a valid method"); 607 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete 608 } else { 609 return true; 610 } 611 } 612 613 Method* ConstantPoolCacheEntry::get_interesting_method_entry() { 614 if (!is_method_entry()) { 615 // not a method entry so not interesting by default 616 return NULL; 617 } 618 Method* m = NULL; 619 if (is_vfinal()) { 620 // virtual and final so _f2 contains method ptr instead of vtable index 621 m = f2_as_vfinal_method(); 622 } else if (is_f1_null()) { 623 // NULL _f1 means this is a virtual entry so also not interesting 624 return NULL; 625 } else { 626 if (!(_f1->is_method())) { 627 // _f1 is a Klass* for an interface 628 m = f2_as_interface_method(); 629 } else { 630 m = f1_as_method(); 631 } 632 } 633 assert(m != NULL && m->is_method(), "sanity check"); 634 if (m == NULL || !m->is_method()) { 635 return NULL; 636 } 637 return m; 638 } 639 #endif // INCLUDE_JVMTI 640 641 void ConstantPoolCacheEntry::print(outputStream* st, int index) const { 642 // print separator 643 if (index == 0) st->print_cr(" -------------"); 644 // print entry 645 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this); 646 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), 647 constant_pool_index()); 648 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1); 649 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2); 650 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags); 651 st->print_cr(" -------------"); 652 } 653 654 void ConstantPoolCacheEntry::verify(outputStream* st) const { 655 // not implemented yet 656 } 657 658 // Implementation of ConstantPoolCache 659 660 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data, 661 const intStack& index_map, 662 const intStack& invokedynamic_index_map, 663 const intStack& invokedynamic_map, TRAPS) { 664 665 const int length = index_map.length() + invokedynamic_index_map.length(); 666 int size = ConstantPoolCache::size(length); 667 668 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD) 669 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map); 670 } 671 672 void ConstantPoolCache::initialize(const intArray& inverse_index_map, 673 const intArray& invokedynamic_inverse_index_map, 674 const intArray& invokedynamic_references_map) { 675 for (int i = 0; i < inverse_index_map.length(); i++) { 676 ConstantPoolCacheEntry* e = entry_at(i); 677 int original_index = inverse_index_map.at(i); 678 e->initialize_entry(original_index); 679 assert(entry_at(i) == e, "sanity"); 680 } 681 682 // Append invokedynamic entries at the end 683 int invokedynamic_offset = inverse_index_map.length(); 684 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) { 685 int offset = i + invokedynamic_offset; 686 ConstantPoolCacheEntry* e = entry_at(offset); 687 int original_index = invokedynamic_inverse_index_map.at(i); 688 e->initialize_entry(original_index); 689 assert(entry_at(offset) == e, "sanity"); 690 } 691 692 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) { 693 const int cpci = invokedynamic_references_map.at(ref); 694 if (cpci >= 0) { 695 entry_at(cpci)->initialize_resolved_reference_index(ref); 696 } 697 } 698 } 699 700 void ConstantPoolCache::verify_just_initialized() { 701 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true)); 702 } 703 704 void ConstantPoolCache::remove_unshareable_info() { 705 walk_entries_for_initialization(/*check_only = */ false); 706 } 707 708 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) { 709 assert(DumpSharedSpaces, "sanity"); 710 // When dumping the archive, we want to clean up the ConstantPoolCache 711 // to remove any effect of linking due to the execution of Java code -- 712 // each ConstantPoolCacheEntry will have the same contents as if 713 // ConstantPoolCache::initialize has just returned: 714 // 715 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries. 716 // - We keep the "f2" field for entries used by invokedynamic and invokehandle 717 // - All other bits in the entries are cleared to zero. 718 ResourceMark rm; 719 720 InstanceKlass* ik = constant_pool()->pool_holder(); 721 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length()); 722 memset(f2_used, 0, sizeof(bool) * length()); 723 724 // Find all the slots that we need to preserve f2 725 for (int i = 0; i < ik->methods()->length(); i++) { 726 Method* m = ik->methods()->at(i); 727 RawBytecodeStream bcs(m); 728 while (!bcs.is_last_bytecode()) { 729 Bytecodes::Code opcode = bcs.raw_next(); 730 switch (opcode) { 731 case Bytecodes::_invokedynamic: { 732 int index = Bytes::get_native_u4(bcs.bcp() + 1); 733 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index); 734 f2_used[cp_cache_index] = 1; 735 } 736 break; 737 case Bytecodes::_invokehandle: { 738 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1); 739 f2_used[cp_cache_index] = 1; 740 } 741 break; 742 default: 743 break; 744 } 745 } 746 } 747 748 if (check_only) { 749 DEBUG_ONLY( 750 for (int i=0; i<length(); i++) { 751 entry_at(i)->verify_just_initialized(f2_used[i]); 752 }) 753 } else { 754 for (int i=0; i<length(); i++) { 755 entry_at(i)->reinitialize(f2_used[i]); 756 } 757 } 758 } 759 760 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) { 761 assert(!is_shared(), "shared caches are not deallocated"); 762 data->remove_handle(_resolved_references); 763 set_resolved_references(NULL); 764 MetadataFactory::free_array<u2>(data, _reference_map); 765 set_reference_map(NULL); 766 } 767 768 #if INCLUDE_CDS_JAVA_HEAP 769 oop ConstantPoolCache::archived_references() { 770 if (CompressedOops::is_null(_archived_references)) { 771 return NULL; 772 } 773 return HeapShared::materialize_archived_object(_archived_references); 774 } 775 776 void ConstantPoolCache::set_archived_references(oop o) { 777 assert(DumpSharedSpaces, "called only during runtime"); 778 _archived_references = CompressedOops::encode(o); 779 } 780 #endif 781 782 #if INCLUDE_JVMTI 783 // RedefineClasses() API support: 784 // If any entry of this ConstantPoolCache points to any of 785 // old_methods, replace it with the corresponding new_method. 786 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) { 787 for (int i = 0; i < length(); i++) { 788 ConstantPoolCacheEntry* entry = entry_at(i); 789 Method* old_method = entry->get_interesting_method_entry(); 790 if (old_method == NULL || !old_method->is_old()) { 791 continue; // skip uninteresting entries 792 } 793 if (old_method->is_deleted()) { 794 // clean up entries with deleted methods 795 entry->initialize_entry(entry->constant_pool_index()); 796 continue; 797 } 798 Method* new_method = old_method->get_new_method(); 799 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed); 800 } 801 } 802 803 // the constant pool cache should never contain old or obsolete methods 804 bool ConstantPoolCache::check_no_old_or_obsolete_entries() { 805 for (int i = 1; i < length(); i++) { 806 if (entry_at(i)->get_interesting_method_entry() != NULL && 807 !entry_at(i)->check_no_old_or_obsolete_entries()) { 808 return false; 809 } 810 } 811 return true; 812 } 813 814 void ConstantPoolCache::dump_cache() { 815 for (int i = 1; i < length(); i++) { 816 if (entry_at(i)->get_interesting_method_entry() != NULL) { 817 entry_at(i)->print(tty, i); 818 } 819 } 820 } 821 #endif // INCLUDE_JVMTI 822 823 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) { 824 log_trace(cds)("Iter(ConstantPoolCache): %p", this); 825 it->push(&_constant_pool); 826 it->push(&_reference_map); 827 } 828 829 // Printing 830 831 void ConstantPoolCache::print_on(outputStream* st) const { 832 st->print_cr("%s", internal_name()); 833 // print constant pool cache entries 834 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i); 835 } 836 837 void ConstantPoolCache::print_value_on(outputStream* st) const { 838 st->print("cache [%d]", length()); 839 print_address_on(st); 840 st->print(" for "); 841 constant_pool()->print_value_on(st); 842 } 843 844 845 // Verification 846 847 void ConstantPoolCache::verify_on(outputStream* st) { 848 // print constant pool cache entries 849 for (int i = 0; i < length(); i++) entry_at(i)->verify(st); 850 }