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 "oops/access.inline.hpp" 39 #include "oops/compressedOops.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 "utilities/macros.hpp" 48 49 // Implementation of ConstantPoolCacheEntry 50 51 void ConstantPoolCacheEntry::initialize_entry(int index) { 52 assert(0 < index && index < 0x10000, "sanity check"); 53 _indices = index; 54 _f1 = NULL; 55 _f2 = _flags = 0; 56 assert(constant_pool_index() == index, ""); 57 } 58 59 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) { 60 assert((_indices & (~cp_index_mask)) == 0, "sanity"); 61 assert(_f1 == NULL, "sanity"); 62 assert(_flags == 0, "sanity"); 63 if (!f2_used) { 64 assert(_f2 == 0, "sanity"); 65 } 66 } 67 68 void ConstantPoolCacheEntry::reinitialize(bool f2_used) { 69 _indices &= cp_index_mask; 70 _f1 = NULL; 71 _flags = 0; 72 if (!f2_used) { 73 _f2 = 0; 74 } 75 } 76 77 int ConstantPoolCacheEntry::make_flags(TosState state, 78 int option_bits, 79 int field_index_or_method_params) { 80 assert(state < number_of_states, "Invalid state in make_flags"); 81 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params; 82 // Preserve existing flag bit values 83 // The low bits are a field offset, or else the method parameter size. 84 #ifdef ASSERT 85 TosState old_state = flag_state(); 86 assert(old_state == (TosState)0 || old_state == state, 87 "inconsistent cpCache flags state"); 88 #endif 89 return (_flags | f) ; 90 } 91 92 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) { 93 #ifdef ASSERT 94 // Read once. 95 volatile Bytecodes::Code c = bytecode_1(); 96 assert(c == 0 || c == code || code == 0, "update must be consistent"); 97 #endif 98 // Need to flush pending stores here before bytecode is written. 99 Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift)); 100 } 101 102 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) { 103 #ifdef ASSERT 104 // Read once. 105 volatile Bytecodes::Code c = bytecode_2(); 106 assert(c == 0 || c == code || code == 0, "update must be consistent"); 107 #endif 108 // Need to flush pending stores here before bytecode is written. 109 Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift)); 110 } 111 112 // Sets f1, ordering with previous writes. 113 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) { 114 assert(f1 != NULL, ""); 115 Atomic::release_store(&_f1, f1); 116 } 117 118 void ConstantPoolCacheEntry::set_indy_resolution_failed() { 119 Atomic::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift)); 120 } 121 122 // Note that concurrent update of both bytecodes can leave one of them 123 // reset to zero. This is harmless; the interpreter will simply re-resolve 124 // the damaged entry. More seriously, the memory synchronization is needed 125 // to flush other fields (f1, f2) completely to memory before the bytecodes 126 // are updated, lest other processors see a non-zero bytecode but zero f1/f2. 127 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code, 128 Bytecodes::Code put_code, 129 Klass* field_holder, 130 int field_index, 131 int field_offset, 132 TosState field_type, 133 bool is_final, 134 bool is_volatile, 135 bool is_tsan_ignore, 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 ((is_tsan_ignore ? 1 : 0) << is_tsan_ignore_shift), 145 field_index); 146 set_bytecode_1(get_code); 147 set_bytecode_2(put_code); 148 NOT_PRODUCT(verify(tty)); 149 } 150 151 void ConstantPoolCacheEntry::set_parameter_size(int value) { 152 // This routine is called only in corner cases where the CPCE is not yet initialized. 153 // See AbstractInterpreter::deopt_continue_after_entry. 154 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value, 155 "size must not change: parameter_size=%d, value=%d", parameter_size(), value); 156 // Setting the parameter size by itself is only safe if the 157 // current value of _flags is 0, otherwise another thread may have 158 // updated it and we don't want to overwrite that value. Don't 159 // bother trying to update it once it's nonzero but always make 160 // sure that the final parameter size agrees with what was passed. 161 if (_flags == 0) { 162 intx newflags = (value & parameter_size_mask); 163 Atomic::cmpxchg(&_flags, (intx)0, newflags); 164 } 165 guarantee(parameter_size() == value, 166 "size must not change: parameter_size=%d, value=%d", parameter_size(), value); 167 } 168 169 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code, 170 const methodHandle& method, 171 int vtable_index, 172 bool sender_is_interface) { 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 if (invoke_code == Bytecodes::_invokestatic) { 266 assert(method->method_holder()->is_initialized() || 267 method->method_holder()->is_reentrant_initialization(Thread::current()), 268 "invalid class initialization state for invoke_static"); 269 270 if (!VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) { 271 // Don't mark invokestatic to method as resolved if the holder class has not yet completed 272 // initialization. An invokestatic must only proceed if the class is initialized, but if 273 // we resolve it before then that class initialization check is skipped. 274 // 275 // When fast class initialization checks are supported (VM_Version::supports_fast_class_init_checks() == true), 276 // template interpreter supports fast class initialization check for 277 // invokestatic which doesn't require call site re-resolution to 278 // enforce class initialization barrier. 279 do_resolve = false; 280 } 281 } 282 if (do_resolve) { 283 set_bytecode_1(invoke_code); 284 } 285 } else if (byte_no == 2) { 286 if (change_to_virtual) { 287 assert(invoke_code == Bytecodes::_invokeinterface, ""); 288 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!! 289 // 290 // Workaround for the case where we encounter an invokeinterface, but we 291 // should really have an _invokevirtual since the resolved method is a 292 // virtual method in java.lang.Object. This is a corner case in the spec 293 // but is presumably legal. javac does not generate this code. 294 // 295 // We do not set bytecode_1() to _invokeinterface, because that is the 296 // bytecode # used by the interpreter to see if it is resolved. In this 297 // case, the method gets reresolved with caller for each interface call 298 // because the actual selected method may not be public. 299 // 300 // We set bytecode_2() to _invokevirtual. 301 // See also interpreterRuntime.cpp. (8/25/2000) 302 } else { 303 assert(invoke_code == Bytecodes::_invokevirtual || 304 (invoke_code == Bytecodes::_invokeinterface && 305 ((method->is_private() || 306 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))), 307 "unexpected invocation mode"); 308 if (invoke_code == Bytecodes::_invokeinterface && 309 (method->is_private() || method->is_final())) { 310 // We set bytecode_1() to _invokeinterface, because that is the 311 // bytecode # used by the interpreter to see if it is resolved. 312 // We set bytecode_2() to _invokevirtual. 313 set_bytecode_1(invoke_code); 314 } 315 } 316 // set up for invokevirtual, even if linking for invokeinterface also: 317 set_bytecode_2(Bytecodes::_invokevirtual); 318 } else { 319 ShouldNotReachHere(); 320 } 321 NOT_PRODUCT(verify(tty)); 322 } 323 324 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method, 325 bool sender_is_interface) { 326 int index = Method::nonvirtual_vtable_index; 327 // index < 0; FIXME: inline and customize set_direct_or_vtable_call 328 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface); 329 } 330 331 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) { 332 // either the method is a miranda or its holder should accept the given index 333 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), ""); 334 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call 335 set_direct_or_vtable_call(invoke_code, method, index, false); 336 } 337 338 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, 339 Klass* referenced_klass, 340 const methodHandle& method, int index) { 341 assert(method->method_holder()->verify_itable_index(index), ""); 342 assert(invoke_code == Bytecodes::_invokeinterface, ""); 343 InstanceKlass* interf = method->method_holder(); 344 assert(interf->is_interface(), "must be an interface"); 345 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here"); 346 set_f1(referenced_klass); 347 set_f2((intx)method()); 348 set_method_flags(as_TosState(method->result_type()), 349 0, // no option bits 350 method()->size_of_parameters()); 351 set_bytecode_1(Bytecodes::_invokeinterface); 352 } 353 354 355 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) { 356 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info); 357 } 358 359 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) { 360 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info); 361 } 362 363 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool, 364 Bytecodes::Code invoke_code, 365 const CallInfo &call_info) { 366 // NOTE: This CPCE can be the subject of data races. 367 // There are three words to update: flags, refs[f2], f1 (in that order). 368 // Writers must store all other values before f1. 369 // Readers must test f1 first for non-null before reading other fields. 370 // Competing writers must acquire exclusive access via a lock. 371 // A losing writer waits on the lock until the winner writes f1 and leaves 372 // the lock, so that when the losing writer returns, he can use the linked 373 // cache entry. 374 375 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 376 // Use the resolved_references() lock for this cpCache entry. 377 // resolved_references are created for all classes with Invokedynamic, MethodHandle 378 // or MethodType constant pool cache entries. 379 assert(resolved_references() != NULL, 380 "a resolved_references array should have been created for this class"); 381 ObjectLocker ol(resolved_references, Thread::current()); 382 if (!is_f1_null()) { 383 return; 384 } 385 386 if (indy_resolution_failed()) { 387 // Before we got here, another thread got a LinkageError exception during 388 // resolution. Ignore our success and throw their exception. 389 ConstantPoolCache* cpCache = cpool->cache(); 390 int index = -1; 391 for (int i = 0; i < cpCache->length(); i++) { 392 if (cpCache->entry_at(i) == this) { 393 index = i; 394 break; 395 } 396 } 397 guarantee(index >= 0, "Didn't find cpCache entry!"); 398 int encoded_index = ResolutionErrorTable::encode_cpcache_index( 399 ConstantPool::encode_invokedynamic_index(index)); 400 Thread* THREAD = Thread::current(); 401 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD); 402 return; 403 } 404 405 Method* adapter = call_info.resolved_method(); 406 const Handle appendix = call_info.resolved_appendix(); 407 const bool has_appendix = appendix.not_null(); 408 409 // Write the flags. 410 // MHs and indy are always sig-poly and have a local signature. 411 set_method_flags(as_TosState(adapter->result_type()), 412 ((has_appendix ? 1 : 0) << has_appendix_shift ) | 413 ( 1 << has_local_signature_shift ) | 414 ( 1 << is_final_shift ), 415 adapter->size_of_parameters()); 416 417 if (TraceInvokeDynamic) { 418 ttyLocker ttyl; 419 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ", 420 invoke_code, 421 p2i(appendix()), 422 (has_appendix ? "" : " (unused)"), 423 p2i(adapter)); 424 adapter->print(); 425 if (has_appendix) appendix()->print(); 426 } 427 428 // Method handle invokes and invokedynamic sites use both cp cache words. 429 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter. 430 // In the general case, this could be the call site's MethodType, 431 // for use with java.lang.Invokers.checkExactType, or else a CallSite object. 432 // f1 contains the adapter method which manages the actual call. 433 // In the general case, this is a compiled LambdaForm. 434 // (The Java code is free to optimize these calls by binding other 435 // sorts of methods and appendices to call sites.) 436 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased. 437 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits. 438 // Even with the appendix, the method will never take more than 255 parameter slots. 439 // 440 // This means that given a call site like (List)mh.invoke("foo"), 441 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;', 442 // not '(Ljava/lang/String;)Ljava/util/List;'. 443 // The fact that String and List are involved is encoded in the MethodType in refs[f2]. 444 // This allows us to create fewer Methods, while keeping type safety. 445 // 446 447 // Store appendix, if any. 448 if (has_appendix) { 449 const int appendix_index = f2_as_index(); 450 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob"); 451 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once"); 452 resolved_references->obj_at_put(appendix_index, appendix()); 453 } 454 455 release_set_f1(adapter); // This must be the last one to set (see NOTE above)! 456 457 // The interpreter assembly code does not check byte_2, 458 // but it is used by is_resolved, method_if_resolved, etc. 459 set_bytecode_1(invoke_code); 460 NOT_PRODUCT(verify(tty)); 461 if (TraceInvokeDynamic) { 462 ttyLocker ttyl; 463 this->print(tty, 0); 464 } 465 466 assert(has_appendix == this->has_appendix(), "proper storage of appendix flag"); 467 assert(this->has_local_signature(), "proper storage of signature flag"); 468 } 469 470 bool ConstantPoolCacheEntry::save_and_throw_indy_exc( 471 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) { 472 473 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!"); 474 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()), 475 "No LinkageError exception"); 476 477 // Use the resolved_references() lock for this cpCache entry. 478 // resolved_references are created for all classes with Invokedynamic, MethodHandle 479 // or MethodType constant pool cache entries. 480 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 481 assert(resolved_references() != NULL, 482 "a resolved_references array should have been created for this class"); 483 ObjectLocker ol(resolved_references, THREAD); 484 485 // if f1 is not null or the indy_resolution_failed flag is set then another 486 // thread either succeeded in resolving the method or got a LinkageError 487 // exception, before this thread was able to record its failure. So, clear 488 // this thread's exception and return false so caller can use the earlier 489 // thread's result. 490 if (!is_f1_null() || indy_resolution_failed()) { 491 CLEAR_PENDING_EXCEPTION; 492 return false; 493 } 494 495 Symbol* error = PENDING_EXCEPTION->klass()->name(); 496 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION); 497 498 SystemDictionary::add_resolution_error(cpool, index, error, message); 499 set_indy_resolution_failed(); 500 return true; 501 } 502 503 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) { 504 // Decode the action of set_method and set_interface_call 505 Bytecodes::Code invoke_code = bytecode_1(); 506 if (invoke_code != (Bytecodes::Code)0) { 507 Metadata* f1 = f1_ord(); 508 if (f1 != NULL) { 509 switch (invoke_code) { 510 case Bytecodes::_invokeinterface: 511 assert(f1->is_klass(), ""); 512 return f2_as_interface_method(); 513 case Bytecodes::_invokestatic: 514 case Bytecodes::_invokespecial: 515 assert(!has_appendix(), ""); 516 case Bytecodes::_invokehandle: 517 case Bytecodes::_invokedynamic: 518 assert(f1->is_method(), ""); 519 return (Method*)f1; 520 default: 521 break; 522 } 523 } 524 } 525 invoke_code = bytecode_2(); 526 if (invoke_code != (Bytecodes::Code)0) { 527 switch (invoke_code) { 528 case Bytecodes::_invokevirtual: 529 if (is_vfinal()) { 530 // invokevirtual 531 Method* m = f2_as_vfinal_method(); 532 assert(m->is_method(), ""); 533 return m; 534 } else { 535 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index()); 536 if (cpool->tag_at(holder_index).is_klass()) { 537 Klass* klass = cpool->resolved_klass_at(holder_index); 538 return klass->method_at_vtable(f2_as_index()); 539 } 540 } 541 break; 542 default: 543 break; 544 } 545 } 546 return NULL; 547 } 548 549 550 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) { 551 if (!has_appendix()) 552 return NULL; 553 const int ref_index = f2_as_index(); 554 objArrayOop resolved_references = cpool->resolved_references(); 555 return resolved_references->obj_at(ref_index); 556 } 557 558 559 #if INCLUDE_JVMTI 560 561 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) { 562 if (log_is_enabled(Info, redefine, class, update)) { 563 ResourceMark rm; 564 if (!(*trace_name_printed)) { 565 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name()); 566 *trace_name_printed = true; 567 } 568 log_debug(redefine, class, update, constantpool) 569 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 570 } 571 } 572 573 // RedefineClasses() API support: 574 // If this ConstantPoolCacheEntry refers to old_method then update it 575 // to refer to new_method. 576 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method, 577 Method* new_method, bool * trace_name_printed) { 578 579 if (is_vfinal()) { 580 // virtual and final so _f2 contains method ptr instead of vtable index 581 if (f2_as_vfinal_method() == old_method) { 582 // match old_method so need an update 583 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values 584 _f2 = (intptr_t)new_method; 585 log_adjust("vfinal", old_method, new_method, trace_name_printed); 586 } 587 return; 588 } 589 590 assert (_f1 != NULL, "should not call with uninteresting entry"); 591 592 if (!(_f1->is_method())) { 593 // _f1 is a Klass* for an interface, _f2 is the method 594 if (f2_as_interface_method() == old_method) { 595 _f2 = (intptr_t)new_method; 596 log_adjust("interface", old_method, new_method, trace_name_printed); 597 } 598 } else if (_f1 == old_method) { 599 _f1 = new_method; 600 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed); 601 } 602 } 603 604 // a constant pool cache entry should never contain old or obsolete methods 605 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() { 606 Method* m = get_interesting_method_entry(); 607 // return false if m refers to a non-deleted old or obsolete method 608 if (m != NULL) { 609 assert(m->is_valid() && m->is_method(), "m is a valid method"); 610 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete 611 } else { 612 return true; 613 } 614 } 615 616 Method* ConstantPoolCacheEntry::get_interesting_method_entry() { 617 if (!is_method_entry()) { 618 // not a method entry so not interesting by default 619 return NULL; 620 } 621 Method* m = NULL; 622 if (is_vfinal()) { 623 // virtual and final so _f2 contains method ptr instead of vtable index 624 m = f2_as_vfinal_method(); 625 } else if (is_f1_null()) { 626 // NULL _f1 means this is a virtual entry so also not interesting 627 return NULL; 628 } else { 629 if (!(_f1->is_method())) { 630 // _f1 is a Klass* for an interface 631 m = f2_as_interface_method(); 632 } else { 633 m = f1_as_method(); 634 } 635 } 636 assert(m != NULL && m->is_method(), "sanity check"); 637 if (m == NULL || !m->is_method()) { 638 return NULL; 639 } 640 return m; 641 } 642 #endif // INCLUDE_JVMTI 643 644 void ConstantPoolCacheEntry::print(outputStream* st, int index) const { 645 // print separator 646 if (index == 0) st->print_cr(" -------------"); 647 // print entry 648 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this); 649 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), 650 constant_pool_index()); 651 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1); 652 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2); 653 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags); 654 st->print_cr(" -------------"); 655 } 656 657 void ConstantPoolCacheEntry::verify(outputStream* st) const { 658 // not implemented yet 659 } 660 661 // Implementation of ConstantPoolCache 662 663 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data, 664 const intStack& index_map, 665 const intStack& invokedynamic_index_map, 666 const intStack& invokedynamic_map, TRAPS) { 667 668 const int length = index_map.length() + invokedynamic_index_map.length(); 669 int size = ConstantPoolCache::size(length); 670 671 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD) 672 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map); 673 } 674 675 void ConstantPoolCache::initialize(const intArray& inverse_index_map, 676 const intArray& invokedynamic_inverse_index_map, 677 const intArray& invokedynamic_references_map) { 678 for (int i = 0; i < inverse_index_map.length(); i++) { 679 ConstantPoolCacheEntry* e = entry_at(i); 680 int original_index = inverse_index_map.at(i); 681 e->initialize_entry(original_index); 682 assert(entry_at(i) == e, "sanity"); 683 } 684 685 // Append invokedynamic entries at the end 686 int invokedynamic_offset = inverse_index_map.length(); 687 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) { 688 int offset = i + invokedynamic_offset; 689 ConstantPoolCacheEntry* e = entry_at(offset); 690 int original_index = invokedynamic_inverse_index_map.at(i); 691 e->initialize_entry(original_index); 692 assert(entry_at(offset) == e, "sanity"); 693 } 694 695 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) { 696 const int cpci = invokedynamic_references_map.at(ref); 697 if (cpci >= 0) { 698 entry_at(cpci)->initialize_resolved_reference_index(ref); 699 } 700 } 701 } 702 703 void ConstantPoolCache::verify_just_initialized() { 704 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true)); 705 } 706 707 void ConstantPoolCache::remove_unshareable_info() { 708 walk_entries_for_initialization(/*check_only = */ false); 709 } 710 711 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) { 712 Arguments::assert_is_dumping_archive(); 713 // When dumping the archive, we want to clean up the ConstantPoolCache 714 // to remove any effect of linking due to the execution of Java code -- 715 // each ConstantPoolCacheEntry will have the same contents as if 716 // ConstantPoolCache::initialize has just returned: 717 // 718 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries. 719 // - We keep the "f2" field for entries used by invokedynamic and invokehandle 720 // - All other bits in the entries are cleared to zero. 721 ResourceMark rm; 722 723 InstanceKlass* ik = constant_pool()->pool_holder(); 724 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length()); 725 memset(f2_used, 0, sizeof(bool) * length()); 726 727 Thread* THREAD = Thread::current(); 728 729 // Find all the slots that we need to preserve f2 730 for (int i = 0; i < ik->methods()->length(); i++) { 731 Method* m = ik->methods()->at(i); 732 RawBytecodeStream bcs(methodHandle(THREAD, m)); 733 while (!bcs.is_last_bytecode()) { 734 Bytecodes::Code opcode = bcs.raw_next(); 735 switch (opcode) { 736 case Bytecodes::_invokedynamic: { 737 int index = Bytes::get_native_u4(bcs.bcp() + 1); 738 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index); 739 f2_used[cp_cache_index] = 1; 740 } 741 break; 742 case Bytecodes::_invokehandle: { 743 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1); 744 f2_used[cp_cache_index] = 1; 745 } 746 break; 747 default: 748 break; 749 } 750 } 751 } 752 753 if (check_only) { 754 DEBUG_ONLY( 755 for (int i=0; i<length(); i++) { 756 entry_at(i)->verify_just_initialized(f2_used[i]); 757 }) 758 } else { 759 for (int i=0; i<length(); i++) { 760 entry_at(i)->reinitialize(f2_used[i]); 761 } 762 } 763 } 764 765 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) { 766 assert(!is_shared(), "shared caches are not deallocated"); 767 data->remove_handle(_resolved_references); 768 set_resolved_references(NULL); 769 MetadataFactory::free_array<u2>(data, _reference_map); 770 set_reference_map(NULL); 771 } 772 773 #if INCLUDE_CDS_JAVA_HEAP 774 oop ConstantPoolCache::archived_references() { 775 if (CompressedOops::is_null(_archived_references)) { 776 return NULL; 777 } 778 return HeapShared::materialize_archived_object(_archived_references); 779 } 780 781 void ConstantPoolCache::set_archived_references(oop o) { 782 assert(DumpSharedSpaces, "called only during runtime"); 783 _archived_references = CompressedOops::encode(o); 784 } 785 #endif 786 787 #if INCLUDE_JVMTI 788 // RedefineClasses() API support: 789 // If any entry of this ConstantPoolCache points to any of 790 // old_methods, replace it with the corresponding new_method. 791 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) { 792 for (int i = 0; i < length(); i++) { 793 ConstantPoolCacheEntry* entry = entry_at(i); 794 Method* old_method = entry->get_interesting_method_entry(); 795 if (old_method == NULL || !old_method->is_old()) { 796 continue; // skip uninteresting entries 797 } 798 if (old_method->is_deleted()) { 799 // clean up entries with deleted methods 800 entry->initialize_entry(entry->constant_pool_index()); 801 continue; 802 } 803 Method* new_method = old_method->get_new_method(); 804 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed); 805 } 806 } 807 808 // the constant pool cache should never contain old or obsolete methods 809 bool ConstantPoolCache::check_no_old_or_obsolete_entries() { 810 for (int i = 1; i < length(); i++) { 811 if (entry_at(i)->get_interesting_method_entry() != NULL && 812 !entry_at(i)->check_no_old_or_obsolete_entries()) { 813 return false; 814 } 815 } 816 return true; 817 } 818 819 void ConstantPoolCache::dump_cache() { 820 for (int i = 1; i < length(); i++) { 821 if (entry_at(i)->get_interesting_method_entry() != NULL) { 822 entry_at(i)->print(tty, i); 823 } 824 } 825 } 826 #endif // INCLUDE_JVMTI 827 828 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) { 829 log_trace(cds)("Iter(ConstantPoolCache): %p", this); 830 it->push(&_constant_pool); 831 it->push(&_reference_map); 832 } 833 834 // Printing 835 836 void ConstantPoolCache::print_on(outputStream* st) const { 837 st->print_cr("%s", internal_name()); 838 // print constant pool cache entries 839 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i); 840 } 841 842 void ConstantPoolCache::print_value_on(outputStream* st) const { 843 st->print("cache [%d]", length()); 844 print_address_on(st); 845 st->print(" for "); 846 constant_pool()->print_value_on(st); 847 } 848 849 850 // Verification 851 852 void ConstantPoolCache::verify_on(outputStream* st) { 853 // print constant pool cache entries 854 for (int i = 0; i < length(); i++) entry_at(i)->verify(st); 855 }