1 /* 2 * Copyright (c) 1998, 2017, 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 "interpreter/bytecodeStream.hpp" 27 #include "interpreter/bytecodes.hpp" 28 #include "interpreter/interpreter.hpp" 29 #include "interpreter/rewriter.hpp" 30 #include "logging/log.hpp" 31 #include "memory/metadataFactory.hpp" 32 #include "memory/metaspaceClosure.hpp" 33 #include "memory/resourceArea.hpp" 34 #include "memory/universe.inline.hpp" 35 #include "oops/cpCache.hpp" 36 #include "oops/objArrayOop.inline.hpp" 37 #include "oops/oop.inline.hpp" 38 #include "prims/methodHandles.hpp" 39 #include "runtime/atomic.hpp" 40 #include "runtime/handles.inline.hpp" 41 #include "runtime/orderAccess.inline.hpp" 42 #include "utilities/macros.hpp" 43 44 // Implementation of ConstantPoolCacheEntry 45 46 void ConstantPoolCacheEntry::initialize_entry(int index) { 47 assert(0 < index && index < 0x10000, "sanity check"); 48 _indices = index; 49 _f1 = NULL; 50 _f2 = _flags = 0; 51 assert(constant_pool_index() == index, ""); 52 } 53 54 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) { 55 assert((_indices & (~cp_index_mask)) == 0, "sanity"); 56 assert(_f1 == NULL, "sanity"); 57 assert(_flags == 0, "sanity"); 58 if (!f2_used) { 59 assert(_f2 == 0, "sanity"); 60 } 61 } 62 63 void ConstantPoolCacheEntry::reinitialize(bool f2_used) { 64 _indices &= cp_index_mask; 65 _f1 = NULL; 66 _flags = 0; 67 if (!f2_used) { 68 _f2 = 0; 69 } 70 } 71 72 int ConstantPoolCacheEntry::make_flags(TosState state, 73 int option_bits, 74 int field_index_or_method_params) { 75 assert(state < number_of_states, "Invalid state in make_flags"); 76 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params; 77 // Preserve existing flag bit values 78 // The low bits are a field offset, or else the method parameter size. 79 #ifdef ASSERT 80 TosState old_state = flag_state(); 81 assert(old_state == (TosState)0 || old_state == state, 82 "inconsistent cpCache flags state"); 83 #endif 84 return (_flags | f) ; 85 } 86 87 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) { 88 #ifdef ASSERT 89 // Read once. 90 volatile Bytecodes::Code c = bytecode_1(); 91 assert(c == 0 || c == code || code == 0, "update must be consistent"); 92 #endif 93 // Need to flush pending stores here before bytecode is written. 94 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift)); 95 } 96 97 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) { 98 #ifdef ASSERT 99 // Read once. 100 volatile Bytecodes::Code c = bytecode_2(); 101 assert(c == 0 || c == code || code == 0, "update must be consistent"); 102 #endif 103 // Need to flush pending stores here before bytecode is written. 104 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift)); 105 } 106 107 // Sets f1, ordering with previous writes. 108 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) { 109 assert(f1 != NULL, ""); 110 OrderAccess::release_store(&_f1, f1); 111 } 112 113 // Sets flags, but only if the value was previously zero. 114 bool ConstantPoolCacheEntry::init_flags_atomic(intx flags) { 115 intptr_t result = Atomic::cmpxchg(flags, &_flags, (intx)0); 116 return (result == 0); 117 } 118 119 // Note that concurrent update of both bytecodes can leave one of them 120 // reset to zero. This is harmless; the interpreter will simply re-resolve 121 // the damaged entry. More seriously, the memory synchronization is needed 122 // to flush other fields (f1, f2) completely to memory before the bytecodes 123 // are updated, lest other processors see a non-zero bytecode but zero f1/f2. 124 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code, 125 Bytecodes::Code put_code, 126 Klass* field_holder, 127 int field_index, 128 int field_offset, 129 TosState field_type, 130 bool is_final, 131 bool is_volatile, 132 Klass* root_klass) { 133 set_f1(field_holder); 134 set_f2(field_offset); 135 assert((field_index & field_index_mask) == field_index, 136 "field index does not fit in low flag bits"); 137 set_field_flags(field_type, 138 ((is_volatile ? 1 : 0) << is_volatile_shift) | 139 ((is_final ? 1 : 0) << is_final_shift), 140 field_index); 141 set_bytecode_1(get_code); 142 set_bytecode_2(put_code); 143 NOT_PRODUCT(verify(tty)); 144 } 145 146 void ConstantPoolCacheEntry::set_parameter_size(int value) { 147 // This routine is called only in corner cases where the CPCE is not yet initialized. 148 // See AbstractInterpreter::deopt_continue_after_entry. 149 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value, 150 "size must not change: parameter_size=%d, value=%d", parameter_size(), value); 151 // Setting the parameter size by itself is only safe if the 152 // current value of _flags is 0, otherwise another thread may have 153 // updated it and we don't want to overwrite that value. Don't 154 // bother trying to update it once it's nonzero but always make 155 // sure that the final parameter size agrees with what was passed. 156 if (_flags == 0) { 157 intx newflags = (value & parameter_size_mask); 158 Atomic::cmpxchg(newflags, &_flags, (intx)0); 159 } 160 guarantee(parameter_size() == value, 161 "size must not change: parameter_size=%d, value=%d", parameter_size(), value); 162 } 163 164 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code, 165 const methodHandle& method, 166 int vtable_index, 167 bool sender_is_interface) { 168 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean 169 assert(method->interpreter_entry() != NULL, "should have been set at this point"); 170 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache"); 171 172 int byte_no = -1; 173 bool change_to_virtual = false; 174 175 switch (invoke_code) { 176 case Bytecodes::_invokeinterface: 177 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface 178 // instruction somehow links to a non-interface method (in Object). 179 // In that case, the method has no itable index and must be invoked as a virtual. 180 // Set a flag to keep track of this corner case. 181 change_to_virtual = true; 182 183 // ...and fall through as if we were handling invokevirtual: 184 case Bytecodes::_invokevirtual: 185 { 186 if (!is_vtable_call) { 187 assert(method->can_be_statically_bound(), ""); 188 // set_f2_as_vfinal_method checks if is_vfinal flag is true. 189 set_method_flags(as_TosState(method->result_type()), 190 ( 1 << is_vfinal_shift) | 191 ((method->is_final_method() ? 1 : 0) << is_final_shift) | 192 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift), 193 method()->size_of_parameters()); 194 set_f2_as_vfinal_method(method()); 195 } else { 196 assert(!method->can_be_statically_bound(), ""); 197 assert(vtable_index >= 0, "valid index"); 198 assert(!method->is_final_method(), "sanity"); 199 set_method_flags(as_TosState(method->result_type()), 200 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift), 201 method()->size_of_parameters()); 202 set_f2(vtable_index); 203 } 204 byte_no = 2; 205 break; 206 } 207 208 case Bytecodes::_invokespecial: 209 case Bytecodes::_invokestatic: 210 assert(!is_vtable_call, ""); 211 // Note: Read and preserve the value of the is_vfinal flag on any 212 // invokevirtual bytecode shared with this constant pool cache entry. 213 // It is cheap and safe to consult is_vfinal() at all times. 214 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop. 215 set_method_flags(as_TosState(method->result_type()), 216 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) | 217 ((method->is_final_method() ? 1 : 0) << is_final_shift), 218 method()->size_of_parameters()); 219 set_f1(method()); 220 byte_no = 1; 221 break; 222 default: 223 ShouldNotReachHere(); 224 break; 225 } 226 227 // Note: byte_no also appears in TemplateTable::resolve. 228 if (byte_no == 1) { 229 assert(invoke_code != Bytecodes::_invokevirtual && 230 invoke_code != Bytecodes::_invokeinterface, ""); 231 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver 232 // has to be checked that it is a subclass of the current class every time this bytecode 233 // is executed. 234 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface || 235 method->name() == vmSymbols::object_initializer_name()) { 236 set_bytecode_1(invoke_code); 237 } 238 } else if (byte_no == 2) { 239 if (change_to_virtual) { 240 assert(invoke_code == Bytecodes::_invokeinterface, ""); 241 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!! 242 // 243 // Workaround for the case where we encounter an invokeinterface, but we 244 // should really have an _invokevirtual since the resolved method is a 245 // virtual method in java.lang.Object. This is a corner case in the spec 246 // but is presumably legal. javac does not generate this code. 247 // 248 // We set bytecode_1() to _invokeinterface, because that is the 249 // bytecode # used by the interpreter to see if it is resolved. 250 // We set bytecode_2() to _invokevirtual. 251 // See also interpreterRuntime.cpp. (8/25/2000) 252 // Only set resolved for the invokeinterface case if method is public. 253 // Otherwise, the method needs to be reresolved with caller for each 254 // interface call. 255 if (method->is_public()) set_bytecode_1(invoke_code); 256 } else { 257 assert(invoke_code == Bytecodes::_invokevirtual, ""); 258 } 259 // set up for invokevirtual, even if linking for invokeinterface also: 260 set_bytecode_2(Bytecodes::_invokevirtual); 261 } else { 262 ShouldNotReachHere(); 263 } 264 NOT_PRODUCT(verify(tty)); 265 } 266 267 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method, 268 bool sender_is_interface) { 269 int index = Method::nonvirtual_vtable_index; 270 // index < 0; FIXME: inline and customize set_direct_or_vtable_call 271 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface); 272 } 273 274 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) { 275 // either the method is a miranda or its holder should accept the given index 276 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), ""); 277 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call 278 set_direct_or_vtable_call(invoke_code, method, index, false); 279 } 280 281 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) { 282 assert(method->method_holder()->verify_itable_index(index), ""); 283 assert(invoke_code == Bytecodes::_invokeinterface, ""); 284 InstanceKlass* interf = method->method_holder(); 285 assert(interf->is_interface(), "must be an interface"); 286 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here"); 287 set_f1(interf); 288 set_f2(index); 289 set_method_flags(as_TosState(method->result_type()), 290 0, // no option bits 291 method()->size_of_parameters()); 292 set_bytecode_1(Bytecodes::_invokeinterface); 293 } 294 295 296 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) { 297 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info); 298 } 299 300 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) { 301 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info); 302 } 303 304 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool, 305 Bytecodes::Code invoke_code, 306 const CallInfo &call_info) { 307 // NOTE: This CPCE can be the subject of data races. 308 // There are three words to update: flags, refs[f2], f1 (in that order). 309 // Writers must store all other values before f1. 310 // Readers must test f1 first for non-null before reading other fields. 311 // Competing writers must acquire exclusive access via a lock. 312 // A losing writer waits on the lock until the winner writes f1 and leaves 313 // the lock, so that when the losing writer returns, he can use the linked 314 // cache entry. 315 316 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references()); 317 // Use the resolved_references() lock for this cpCache entry. 318 // resolved_references are created for all classes with Invokedynamic, MethodHandle 319 // or MethodType constant pool cache entries. 320 assert(resolved_references() != NULL, 321 "a resolved_references array should have been created for this class"); 322 ObjectLocker ol(resolved_references, Thread::current()); 323 if (!is_f1_null()) { 324 return; 325 } 326 327 const methodHandle adapter = call_info.resolved_method(); 328 const Handle appendix = call_info.resolved_appendix(); 329 const Handle method_type = call_info.resolved_method_type(); 330 const bool has_appendix = appendix.not_null(); 331 const bool has_method_type = method_type.not_null(); 332 333 // Write the flags. 334 set_method_flags(as_TosState(adapter->result_type()), 335 ((has_appendix ? 1 : 0) << has_appendix_shift ) | 336 ((has_method_type ? 1 : 0) << has_method_type_shift) | 337 ( 1 << is_final_shift ), 338 adapter->size_of_parameters()); 339 340 if (TraceInvokeDynamic) { 341 ttyLocker ttyl; 342 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ", 343 invoke_code, 344 p2i(appendix()), (has_appendix ? "" : " (unused)"), 345 p2i(method_type()), (has_method_type ? "" : " (unused)"), 346 p2i(adapter())); 347 adapter->print(); 348 if (has_appendix) appendix()->print(); 349 } 350 351 // Method handle invokes and invokedynamic sites use both cp cache words. 352 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter. 353 // In the general case, this could be the call site's MethodType, 354 // for use with java.lang.Invokers.checkExactType, or else a CallSite object. 355 // f1 contains the adapter method which manages the actual call. 356 // In the general case, this is a compiled LambdaForm. 357 // (The Java code is free to optimize these calls by binding other 358 // sorts of methods and appendices to call sites.) 359 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased. 360 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits. 361 // Even with the appendix, the method will never take more than 255 parameter slots. 362 // 363 // This means that given a call site like (List)mh.invoke("foo"), 364 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;', 365 // not '(Ljava/lang/String;)Ljava/util/List;'. 366 // The fact that String and List are involved is encoded in the MethodType in refs[f2]. 367 // This allows us to create fewer Methods, while keeping type safety. 368 // 369 370 // Store appendix, if any. 371 if (has_appendix) { 372 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset; 373 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob"); 374 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once"); 375 resolved_references->obj_at_put(appendix_index, appendix()); 376 } 377 378 // Store MethodType, if any. 379 if (has_method_type) { 380 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset; 381 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob"); 382 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once"); 383 resolved_references->obj_at_put(method_type_index, method_type()); 384 } 385 386 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)! 387 388 // The interpreter assembly code does not check byte_2, 389 // but it is used by is_resolved, method_if_resolved, etc. 390 set_bytecode_1(invoke_code); 391 NOT_PRODUCT(verify(tty)); 392 if (TraceInvokeDynamic) { 393 ttyLocker ttyl; 394 this->print(tty, 0); 395 } 396 } 397 398 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) { 399 // Decode the action of set_method and set_interface_call 400 Bytecodes::Code invoke_code = bytecode_1(); 401 if (invoke_code != (Bytecodes::Code)0) { 402 Metadata* f1 = f1_ord(); 403 if (f1 != NULL) { 404 switch (invoke_code) { 405 case Bytecodes::_invokeinterface: 406 assert(f1->is_klass(), ""); 407 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index()); 408 case Bytecodes::_invokestatic: 409 case Bytecodes::_invokespecial: 410 assert(!has_appendix(), ""); 411 case Bytecodes::_invokehandle: 412 case Bytecodes::_invokedynamic: 413 assert(f1->is_method(), ""); 414 return (Method*)f1; 415 default: 416 break; 417 } 418 } 419 } 420 invoke_code = bytecode_2(); 421 if (invoke_code != (Bytecodes::Code)0) { 422 switch (invoke_code) { 423 case Bytecodes::_invokevirtual: 424 if (is_vfinal()) { 425 // invokevirtual 426 Method* m = f2_as_vfinal_method(); 427 assert(m->is_method(), ""); 428 return m; 429 } else { 430 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index()); 431 if (cpool->tag_at(holder_index).is_klass()) { 432 Klass* klass = cpool->resolved_klass_at(holder_index); 433 return klass->method_at_vtable(f2_as_index()); 434 } 435 } 436 break; 437 default: 438 break; 439 } 440 } 441 return NULL; 442 } 443 444 445 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) { 446 if (!has_appendix()) 447 return NULL; 448 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset; 449 objArrayOop resolved_references = cpool->resolved_references(); 450 return resolved_references->obj_at(ref_index); 451 } 452 453 454 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) { 455 if (!has_method_type()) 456 return NULL; 457 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset; 458 objArrayOop resolved_references = cpool->resolved_references(); 459 return resolved_references->obj_at(ref_index); 460 } 461 462 463 #if INCLUDE_JVMTI 464 // RedefineClasses() API support: 465 // If this ConstantPoolCacheEntry refers to old_method then update it 466 // to refer to new_method. 467 bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method, 468 Method* new_method, bool * trace_name_printed) { 469 470 if (is_vfinal()) { 471 // virtual and final so _f2 contains method ptr instead of vtable index 472 if (f2_as_vfinal_method() == old_method) { 473 // match old_method so need an update 474 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values 475 _f2 = (intptr_t)new_method; 476 if (log_is_enabled(Info, redefine, class, update)) { 477 ResourceMark rm; 478 if (!(*trace_name_printed)) { 479 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name()); 480 *trace_name_printed = true; 481 } 482 log_debug(redefine, class, update, constantpool) 483 ("cpc vf-entry update: %s(%s)", new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 484 } 485 return true; 486 } 487 488 // f1() is not used with virtual entries so bail out 489 return false; 490 } 491 492 if (_f1 == NULL) { 493 // NULL f1() means this is a virtual entry so bail out 494 // We are assuming that the vtable index does not need change. 495 return false; 496 } 497 498 if (_f1 == old_method) { 499 _f1 = new_method; 500 if (log_is_enabled(Info, redefine, class, update)) { 501 ResourceMark rm; 502 if (!(*trace_name_printed)) { 503 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name()); 504 *trace_name_printed = true; 505 } 506 log_debug(redefine, class, update, constantpool) 507 ("cpc entry update: %s(%s)", new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 508 } 509 return true; 510 } 511 512 return false; 513 } 514 515 // a constant pool cache entry should never contain old or obsolete methods 516 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() { 517 if (is_vfinal()) { 518 // virtual and final so _f2 contains method ptr instead of vtable index 519 Metadata* f2 = (Metadata*)_f2; 520 // Return false if _f2 refers to an old or an obsolete method. 521 // _f2 == NULL || !_f2->is_method() are just as unexpected here. 522 return (f2 != NULL NOT_PRODUCT(&& f2->is_valid()) && f2->is_method() && 523 !((Method*)f2)->is_old() && !((Method*)f2)->is_obsolete()); 524 } else if (_f1 == NULL || 525 (NOT_PRODUCT(_f1->is_valid() &&) !_f1->is_method())) { 526 // _f1 == NULL || !_f1->is_method() are OK here 527 return true; 528 } 529 // return false if _f1 refers to a non-deleted old or obsolete method 530 return (NOT_PRODUCT(_f1->is_valid() &&) _f1->is_method() && 531 (f1_as_method()->is_deleted() || 532 (!f1_as_method()->is_old() && !f1_as_method()->is_obsolete()))); 533 } 534 535 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) { 536 if (!is_method_entry()) { 537 // not a method entry so not interesting by default 538 return NULL; 539 } 540 Method* m = NULL; 541 if (is_vfinal()) { 542 // virtual and final so _f2 contains method ptr instead of vtable index 543 m = f2_as_vfinal_method(); 544 } else if (is_f1_null()) { 545 // NULL _f1 means this is a virtual entry so also not interesting 546 return NULL; 547 } else { 548 if (!(_f1->is_method())) { 549 // _f1 can also contain a Klass* for an interface 550 return NULL; 551 } 552 m = f1_as_method(); 553 } 554 assert(m != NULL && m->is_method(), "sanity check"); 555 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) { 556 // robustness for above sanity checks or method is not in 557 // the interesting class 558 return NULL; 559 } 560 // the method is in the interesting class so the entry is interesting 561 return m; 562 } 563 #endif // INCLUDE_JVMTI 564 565 void ConstantPoolCacheEntry::print(outputStream* st, int index) const { 566 // print separator 567 if (index == 0) st->print_cr(" -------------"); 568 // print entry 569 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this); 570 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), 571 constant_pool_index()); 572 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1); 573 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2); 574 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags); 575 st->print_cr(" -------------"); 576 } 577 578 void ConstantPoolCacheEntry::verify(outputStream* st) const { 579 // not implemented yet 580 } 581 582 // Implementation of ConstantPoolCache 583 584 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data, 585 const intStack& index_map, 586 const intStack& invokedynamic_index_map, 587 const intStack& invokedynamic_map, TRAPS) { 588 589 const int length = index_map.length() + invokedynamic_index_map.length(); 590 int size = ConstantPoolCache::size(length); 591 592 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD) 593 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map); 594 } 595 596 void ConstantPoolCache::initialize(const intArray& inverse_index_map, 597 const intArray& invokedynamic_inverse_index_map, 598 const intArray& invokedynamic_references_map) { 599 for (int i = 0; i < inverse_index_map.length(); i++) { 600 ConstantPoolCacheEntry* e = entry_at(i); 601 int original_index = inverse_index_map.at(i); 602 e->initialize_entry(original_index); 603 assert(entry_at(i) == e, "sanity"); 604 } 605 606 // Append invokedynamic entries at the end 607 int invokedynamic_offset = inverse_index_map.length(); 608 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) { 609 int offset = i + invokedynamic_offset; 610 ConstantPoolCacheEntry* e = entry_at(offset); 611 int original_index = invokedynamic_inverse_index_map.at(i); 612 e->initialize_entry(original_index); 613 assert(entry_at(offset) == e, "sanity"); 614 } 615 616 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) { 617 const int cpci = invokedynamic_references_map.at(ref); 618 if (cpci >= 0) { 619 #ifdef ASSERT 620 // invokedynamic and invokehandle have more entries; check if they 621 // all point to the same constant pool cache entry. 622 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) { 623 const int cpci_next = invokedynamic_references_map.at(ref + entry); 624 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next); 625 } 626 #endif 627 entry_at(cpci)->initialize_resolved_reference_index(ref); 628 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries 629 } 630 } 631 } 632 633 void ConstantPoolCache::verify_just_initialized() { 634 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true)); 635 } 636 637 void ConstantPoolCache::remove_unshareable_info() { 638 walk_entries_for_initialization(/*check_only = */ false); 639 } 640 641 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) { 642 assert(DumpSharedSpaces, "sanity"); 643 // When dumping the archive, we want to clean up the ConstantPoolCache 644 // to remove any effect of linking due to the execution of Java code -- 645 // each ConstantPoolCacheEntry will have the same contents as if 646 // ConstantPoolCache::initialize has just returned: 647 // 648 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries. 649 // - We keep the "f2" field for entries used by invokedynamic and invokehandle 650 // - All other bits in the entries are cleared to zero. 651 ResourceMark rm; 652 653 InstanceKlass* ik = constant_pool()->pool_holder(); 654 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length()); 655 memset(f2_used, 0, sizeof(bool) * length()); 656 657 // Find all the slots that we need to preserve f2 658 for (int i = 0; i < ik->methods()->length(); i++) { 659 Method* m = ik->methods()->at(i); 660 RawBytecodeStream bcs(m); 661 while (!bcs.is_last_bytecode()) { 662 Bytecodes::Code opcode = bcs.raw_next(); 663 switch (opcode) { 664 case Bytecodes::_invokedynamic: { 665 int index = Bytes::get_native_u4(bcs.bcp() + 1); 666 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index); 667 f2_used[cp_cache_index] = 1; 668 } 669 break; 670 case Bytecodes::_invokehandle: { 671 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1); 672 f2_used[cp_cache_index] = 1; 673 } 674 break; 675 default: 676 break; 677 } 678 } 679 } 680 681 if (check_only) { 682 DEBUG_ONLY( 683 for (int i=0; i<length(); i++) { 684 entry_at(i)->verify_just_initialized(f2_used[i]); 685 }) 686 } else { 687 for (int i=0; i<length(); i++) { 688 entry_at(i)->reinitialize(f2_used[i]); 689 } 690 } 691 } 692 693 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) { 694 assert(!is_shared(), "shared caches are not deallocated"); 695 data->remove_handle(_resolved_references); 696 set_resolved_references(NULL); 697 MetadataFactory::free_array<u2>(data, _reference_map); 698 set_reference_map(NULL); 699 } 700 701 #if INCLUDE_CDS_JAVA_HEAP 702 oop ConstantPoolCache::archived_references() { 703 assert(UseSharedSpaces, "UseSharedSpaces expected."); 704 return oopDesc::decode_heap_oop(_archived_references); 705 } 706 707 void ConstantPoolCache::set_archived_references(oop o) { 708 assert(DumpSharedSpaces, "called only during runtime"); 709 _archived_references = oopDesc::encode_heap_oop(o); 710 } 711 #endif 712 713 #if INCLUDE_JVMTI 714 // RedefineClasses() API support: 715 // If any entry of this ConstantPoolCache points to any of 716 // old_methods, replace it with the corresponding new_method. 717 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) { 718 for (int i = 0; i < length(); i++) { 719 ConstantPoolCacheEntry* entry = entry_at(i); 720 Method* old_method = entry->get_interesting_method_entry(holder); 721 if (old_method == NULL || !old_method->is_old()) { 722 continue; // skip uninteresting entries 723 } 724 if (old_method->is_deleted()) { 725 // clean up entries with deleted methods 726 entry->initialize_entry(entry->constant_pool_index()); 727 continue; 728 } 729 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 730 731 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 732 assert(old_method != new_method, "sanity check"); 733 734 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed); 735 } 736 } 737 738 // the constant pool cache should never contain old or obsolete methods 739 bool ConstantPoolCache::check_no_old_or_obsolete_entries() { 740 for (int i = 1; i < length(); i++) { 741 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL && 742 !entry_at(i)->check_no_old_or_obsolete_entries()) { 743 return false; 744 } 745 } 746 return true; 747 } 748 749 void ConstantPoolCache::dump_cache() { 750 for (int i = 1; i < length(); i++) { 751 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) { 752 entry_at(i)->print(tty, i); 753 } 754 } 755 } 756 #endif // INCLUDE_JVMTI 757 758 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) { 759 log_trace(cds)("Iter(ConstantPoolCache): %p", this); 760 it->push(&_constant_pool); 761 it->push(&_reference_map); 762 } 763 764 // Printing 765 766 void ConstantPoolCache::print_on(outputStream* st) const { 767 assert(is_constantPoolCache(), "obj must be constant pool cache"); 768 st->print_cr("%s", internal_name()); 769 // print constant pool cache entries 770 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i); 771 } 772 773 void ConstantPoolCache::print_value_on(outputStream* st) const { 774 assert(is_constantPoolCache(), "obj must be constant pool cache"); 775 st->print("cache [%d]", length()); 776 print_address_on(st); 777 st->print(" for "); 778 constant_pool()->print_value_on(st); 779 } 780 781 782 // Verification 783 784 void ConstantPoolCache::verify_on(outputStream* st) { 785 guarantee(is_constantPoolCache(), "obj must be constant pool cache"); 786 // print constant pool cache entries 787 for (int i = 0; i < length(); i++) entry_at(i)->verify(st); 788 }