1 /* 2 * Copyright (c) 1997, 2010, 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/systemDictionary.hpp" 27 #include "classfile/vmSymbols.hpp" 28 #include "gc_implementation/shared/markSweep.inline.hpp" 29 #include "memory/gcLocker.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "memory/universe.inline.hpp" 32 #include "oops/instanceKlass.hpp" 33 #include "oops/klassOop.hpp" 34 #include "oops/klassVtable.hpp" 35 #include "oops/methodOop.hpp" 36 #include "oops/objArrayOop.hpp" 37 #include "oops/oop.inline.hpp" 38 #include "prims/jvmtiRedefineClassesTrace.hpp" 39 #include "runtime/arguments.hpp" 40 #include "runtime/handles.inline.hpp" 41 #include "utilities/copy.hpp" 42 43 inline instanceKlass* klassVtable::ik() const { 44 Klass* k = _klass()->klass_part(); 45 assert(k->oop_is_instance(), "not an instanceKlass"); 46 return (instanceKlass*)k; 47 } 48 49 50 // this function computes the vtable size (including the size needed for miranda 51 // methods) and the number of miranda methods in this class 52 // Note on Miranda methods: Let's say there is a class C that implements 53 // interface I. Let's say there is a method m in I that neither C nor any 54 // of its super classes implement (i.e there is no method of any access, with 55 // the same name and signature as m), then m is a Miranda method which is 56 // entered as a public abstract method in C's vtable. From then on it should 57 // treated as any other public method in C for method over-ride purposes. 58 void klassVtable::compute_vtable_size_and_num_mirandas(int &vtable_length, 59 int &num_miranda_methods, 60 klassOop super, 61 objArrayOop methods, 62 AccessFlags class_flags, 63 Handle classloader, 64 symbolHandle classname, 65 objArrayOop local_interfaces, 66 TRAPS 67 ) { 68 69 No_Safepoint_Verifier nsv; 70 71 // set up default result values 72 vtable_length = 0; 73 num_miranda_methods = 0; 74 75 // start off with super's vtable length 76 instanceKlass* sk = (instanceKlass*)super->klass_part(); 77 vtable_length = super == NULL ? 0 : sk->vtable_length(); 78 79 // go thru each method in the methods table to see if it needs a new entry 80 int len = methods->length(); 81 for (int i = 0; i < len; i++) { 82 assert(methods->obj_at(i)->is_method(), "must be a methodOop"); 83 methodHandle mh(THREAD, methodOop(methods->obj_at(i))); 84 85 if (needs_new_vtable_entry(mh, super, classloader, classname, class_flags, THREAD)) { 86 vtable_length += vtableEntry::size(); // we need a new entry 87 } 88 } 89 90 // compute the number of mirandas methods that must be added to the end 91 num_miranda_methods = get_num_mirandas(super, methods, local_interfaces); 92 vtable_length += (num_miranda_methods * vtableEntry::size()); 93 94 if (Universe::is_bootstrapping() && vtable_length == 0) { 95 // array classes don't have their superclass set correctly during 96 // bootstrapping 97 vtable_length = Universe::base_vtable_size(); 98 } 99 100 if (super == NULL && !Universe::is_bootstrapping() && 101 vtable_length != Universe::base_vtable_size()) { 102 // Someone is attempting to redefine java.lang.Object incorrectly. The 103 // only way this should happen is from 104 // SystemDictionary::resolve_from_stream(), which will detect this later 105 // and throw a security exception. So don't assert here to let 106 // the exception occur. 107 vtable_length = Universe::base_vtable_size(); 108 } 109 assert(super != NULL || vtable_length == Universe::base_vtable_size(), 110 "bad vtable size for class Object"); 111 assert(vtable_length % vtableEntry::size() == 0, "bad vtable length"); 112 assert(vtable_length >= Universe::base_vtable_size(), "vtable too small"); 113 } 114 115 int klassVtable::index_of(methodOop m, int len) const { 116 assert(m->vtable_index() >= 0, "do not ask this of non-vtable methods"); 117 return m->vtable_index(); 118 } 119 120 int klassVtable::initialize_from_super(KlassHandle super) { 121 if (super.is_null()) { 122 return 0; 123 } else { 124 // copy methods from superKlass 125 // can't inherit from array class, so must be instanceKlass 126 assert(super->oop_is_instance(), "must be instance klass"); 127 instanceKlass* sk = (instanceKlass*)super()->klass_part(); 128 klassVtable* superVtable = sk->vtable(); 129 assert(superVtable->length() <= _length, "vtable too short"); 130 #ifdef ASSERT 131 superVtable->verify(tty, true); 132 #endif 133 superVtable->copy_vtable_to(table()); 134 #ifndef PRODUCT 135 if (PrintVtables && Verbose) { 136 ResourceMark rm; 137 tty->print_cr("copy vtable from %s to %s size %d", sk->internal_name(), klass()->internal_name(), _length); 138 } 139 #endif 140 return superVtable->length(); 141 } 142 } 143 144 // Revised lookup semantics introduced 1.3 (Kestral beta) 145 void klassVtable::initialize_vtable(bool checkconstraints, TRAPS) { 146 147 // Note: Arrays can have intermediate array supers. Use java_super to skip them. 148 KlassHandle super (THREAD, klass()->java_super()); 149 int nofNewEntries = 0; 150 151 152 if (PrintVtables && !klass()->oop_is_array()) { 153 ResourceMark rm(THREAD); 154 tty->print_cr("Initializing: %s", _klass->name()->as_C_string()); 155 } 156 157 #ifdef ASSERT 158 oop* end_of_obj = (oop*)_klass() + _klass()->size(); 159 oop* end_of_vtable = (oop*)&table()[_length]; 160 assert(end_of_vtable <= end_of_obj, "vtable extends beyond end"); 161 #endif 162 163 if (Universe::is_bootstrapping()) { 164 // just clear everything 165 for (int i = 0; i < _length; i++) table()[i].clear(); 166 return; 167 } 168 169 int super_vtable_len = initialize_from_super(super); 170 if (klass()->oop_is_array()) { 171 assert(super_vtable_len == _length, "arrays shouldn't introduce new methods"); 172 } else { 173 assert(_klass->oop_is_instance(), "must be instanceKlass"); 174 175 objArrayHandle methods(THREAD, ik()->methods()); 176 int len = methods()->length(); 177 int initialized = super_vtable_len; 178 179 // update_inherited_vtable can stop for gc - ensure using handles 180 for (int i = 0; i < len; i++) { 181 HandleMark hm(THREAD); 182 assert(methods()->obj_at(i)->is_method(), "must be a methodOop"); 183 methodHandle mh(THREAD, (methodOop)methods()->obj_at(i)); 184 185 bool needs_new_entry = update_inherited_vtable(ik(), mh, super_vtable_len, checkconstraints, CHECK); 186 187 if (needs_new_entry) { 188 put_method_at(mh(), initialized); 189 mh()->set_vtable_index(initialized); // set primary vtable index 190 initialized++; 191 } 192 } 193 194 // add miranda methods; it will also update the value of initialized 195 fill_in_mirandas(initialized); 196 197 // In class hierarchies where the accessibility is not increasing (i.e., going from private -> 198 // package_private -> publicprotected), the vtable might actually be smaller than our initial 199 // calculation. 200 assert(initialized <= _length, "vtable initialization failed"); 201 for(;initialized < _length; initialized++) { 202 put_method_at(NULL, initialized); 203 } 204 NOT_PRODUCT(verify(tty, true)); 205 } 206 } 207 208 // Called for cases where a method does not override its superclass' vtable entry 209 // For bytecodes not produced by javac together it is possible that a method does not override 210 // the superclass's method, but might indirectly override a super-super class's vtable entry 211 // If none found, return a null superk, else return the superk of the method this does override 212 instanceKlass* klassVtable::find_transitive_override(instanceKlass* initialsuper, methodHandle target_method, 213 int vtable_index, Handle target_loader, symbolHandle target_classname, Thread * THREAD) { 214 instanceKlass* superk = initialsuper; 215 while (superk != NULL && superk->super() != NULL) { 216 instanceKlass* supersuperklass = instanceKlass::cast(superk->super()); 217 klassVtable* ssVtable = supersuperklass->vtable(); 218 if (vtable_index < ssVtable->length()) { 219 methodOop super_method = ssVtable->method_at(vtable_index); 220 #ifndef PRODUCT 221 symbolHandle name(THREAD,target_method()->name()); 222 symbolHandle signature(THREAD,target_method()->signature()); 223 assert(super_method->name() == name() && super_method->signature() == signature(), "vtable entry name/sig mismatch"); 224 #endif 225 if (supersuperklass->is_override(super_method, target_loader, target_classname, THREAD)) { 226 #ifndef PRODUCT 227 if (PrintVtables && Verbose) { 228 ResourceMark rm(THREAD); 229 tty->print("transitive overriding superclass %s with %s::%s index %d, original flags: ", 230 supersuperklass->internal_name(), 231 _klass->internal_name(), (target_method() != NULL) ? 232 target_method()->name()->as_C_string() : "<NULL>", vtable_index); 233 super_method->access_flags().print_on(tty); 234 tty->print("overriders flags: "); 235 target_method->access_flags().print_on(tty); 236 tty->cr(); 237 } 238 #endif /*PRODUCT*/ 239 break; // return found superk 240 } 241 } else { 242 // super class has no vtable entry here, stop transitive search 243 superk = (instanceKlass*)NULL; 244 break; 245 } 246 // if no override found yet, continue to search up 247 superk = instanceKlass::cast(superk->super()); 248 } 249 250 return superk; 251 } 252 253 254 // Update child's copy of super vtable for overrides 255 // OR return true if a new vtable entry is required 256 // Only called for instanceKlass's, i.e. not for arrays 257 // If that changed, could not use _klass as handle for klass 258 bool klassVtable::update_inherited_vtable(instanceKlass* klass, methodHandle target_method, int super_vtable_len, 259 bool checkconstraints, TRAPS) { 260 ResourceMark rm; 261 bool allocate_new = true; 262 assert(klass->oop_is_instance(), "must be instanceKlass"); 263 264 // Initialize the method's vtable index to "nonvirtual". 265 // If we allocate a vtable entry, we will update it to a non-negative number. 266 target_method()->set_vtable_index(methodOopDesc::nonvirtual_vtable_index); 267 268 // Static and <init> methods are never in 269 if (target_method()->is_static() || target_method()->name() == vmSymbols::object_initializer_name()) { 270 return false; 271 } 272 273 if (klass->is_final() || target_method()->is_final()) { 274 // a final method never needs a new entry; final methods can be statically 275 // resolved and they have to be present in the vtable only if they override 276 // a super's method, in which case they re-use its entry 277 allocate_new = false; 278 } 279 280 // we need a new entry if there is no superclass 281 if (klass->super() == NULL) { 282 return allocate_new; 283 } 284 285 // private methods always have a new entry in the vtable 286 // specification interpretation since classic has 287 // private methods not overriding 288 if (target_method()->is_private()) { 289 return allocate_new; 290 } 291 292 // search through the vtable and update overridden entries 293 // Since check_signature_loaders acquires SystemDictionary_lock 294 // which can block for gc, once we are in this loop, use handles 295 // For classfiles built with >= jdk7, we now look for transitive overrides 296 297 symbolHandle name(THREAD,target_method()->name()); 298 symbolHandle signature(THREAD,target_method()->signature()); 299 Handle target_loader(THREAD, _klass->class_loader()); 300 symbolHandle target_classname(THREAD, _klass->name()); 301 for(int i = 0; i < super_vtable_len; i++) { 302 methodOop super_method = method_at(i); 303 // Check if method name matches 304 if (super_method->name() == name() && super_method->signature() == signature()) { 305 306 // get super_klass for method_holder for the found method 307 instanceKlass* super_klass = instanceKlass::cast(super_method->method_holder()); 308 309 if ((super_klass->is_override(super_method, target_loader, target_classname, THREAD)) || 310 ((klass->major_version() >= VTABLE_TRANSITIVE_OVERRIDE_VERSION) 311 && ((super_klass = find_transitive_override(super_klass, target_method, i, target_loader, 312 target_classname, THREAD)) != (instanceKlass*)NULL))) { 313 // overriding, so no new entry 314 allocate_new = false; 315 316 if (checkconstraints) { 317 // Override vtable entry if passes loader constraint check 318 // if loader constraint checking requested 319 // No need to visit his super, since he and his super 320 // have already made any needed loader constraints. 321 // Since loader constraints are transitive, it is enough 322 // to link to the first super, and we get all the others. 323 Handle super_loader(THREAD, super_klass->class_loader()); 324 325 if (target_loader() != super_loader()) { 326 ResourceMark rm(THREAD); 327 char* failed_type_name = 328 SystemDictionary::check_signature_loaders(signature, target_loader, 329 super_loader, true, 330 CHECK_(false)); 331 if (failed_type_name != NULL) { 332 const char* msg = "loader constraint violation: when resolving " 333 "overridden method \"%s\" the class loader (instance" 334 " of %s) of the current class, %s, and its superclass loader " 335 "(instance of %s), have different Class objects for the type " 336 "%s used in the signature"; 337 char* sig = target_method()->name_and_sig_as_C_string(); 338 const char* loader1 = SystemDictionary::loader_name(target_loader()); 339 char* current = _klass->name()->as_C_string(); 340 const char* loader2 = SystemDictionary::loader_name(super_loader()); 341 size_t buflen = strlen(msg) + strlen(sig) + strlen(loader1) + 342 strlen(current) + strlen(loader2) + strlen(failed_type_name); 343 char* buf = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, buflen); 344 jio_snprintf(buf, buflen, msg, sig, loader1, current, loader2, 345 failed_type_name); 346 THROW_MSG_(vmSymbols::java_lang_LinkageError(), buf, false); 347 } 348 } 349 } 350 351 put_method_at(target_method(), i); 352 target_method()->set_vtable_index(i); 353 #ifndef PRODUCT 354 if (PrintVtables && Verbose) { 355 tty->print("overriding with %s::%s index %d, original flags: ", 356 _klass->internal_name(), (target_method() != NULL) ? 357 target_method()->name()->as_C_string() : "<NULL>", i); 358 super_method->access_flags().print_on(tty); 359 tty->print("overriders flags: "); 360 target_method->access_flags().print_on(tty); 361 tty->cr(); 362 } 363 #endif /*PRODUCT*/ 364 } else { 365 // allocate_new = true; default. We might override one entry, 366 // but not override another. Once we override one, not need new 367 #ifndef PRODUCT 368 if (PrintVtables && Verbose) { 369 tty->print("NOT overriding with %s::%s index %d, original flags: ", 370 _klass->internal_name(), (target_method() != NULL) ? 371 target_method()->name()->as_C_string() : "<NULL>", i); 372 super_method->access_flags().print_on(tty); 373 tty->print("overriders flags: "); 374 target_method->access_flags().print_on(tty); 375 tty->cr(); 376 } 377 #endif /*PRODUCT*/ 378 } 379 } 380 } 381 return allocate_new; 382 } 383 384 void klassVtable::put_method_at(methodOop m, int index) { 385 assert(m->is_oop_or_null(), "Not an oop or null"); 386 #ifndef PRODUCT 387 if (PrintVtables && Verbose) { 388 ResourceMark rm; 389 tty->print_cr("adding %s::%s at index %d", _klass->internal_name(), 390 (m != NULL) ? m->name()->as_C_string() : "<NULL>", index); 391 } 392 assert(unchecked_method_at(index)->is_oop_or_null(), "Not an oop or null"); 393 #endif 394 table()[index].set(m); 395 } 396 397 // Find out if a method "m" with superclass "super", loader "classloader" and 398 // name "classname" needs a new vtable entry. Let P be a class package defined 399 // by "classloader" and "classname". 400 // NOTE: The logic used here is very similar to the one used for computing 401 // the vtables indices for a method. We cannot directly use that function because, 402 // we allocate the instanceKlass at load time, and that requires that the 403 // superclass has been loaded. 404 // However, the vtable entries are filled in at link time, and therefore 405 // the superclass' vtable may not yet have been filled in. 406 bool klassVtable::needs_new_vtable_entry(methodHandle target_method, 407 klassOop super, 408 Handle classloader, 409 symbolHandle classname, 410 AccessFlags class_flags, 411 TRAPS) { 412 if ((class_flags.is_final() || target_method()->is_final()) || 413 // a final method never needs a new entry; final methods can be statically 414 // resolved and they have to be present in the vtable only if they override 415 // a super's method, in which case they re-use its entry 416 (target_method()->is_static()) || 417 // static methods don't need to be in vtable 418 (target_method()->name() == vmSymbols::object_initializer_name()) 419 // <init> is never called dynamically-bound 420 ) { 421 return false; 422 } 423 424 // we need a new entry if there is no superclass 425 if (super == NULL) { 426 return true; 427 } 428 429 // private methods always have a new entry in the vtable 430 // specification interpretation since classic has 431 // private methods not overriding 432 if (target_method()->is_private()) { 433 return true; 434 } 435 436 // search through the super class hierarchy to see if we need 437 // a new entry 438 ResourceMark rm; 439 symbolOop name = target_method()->name(); 440 symbolOop signature = target_method()->signature(); 441 klassOop k = super; 442 methodOop super_method = NULL; 443 instanceKlass *holder = NULL; 444 methodOop recheck_method = NULL; 445 while (k != NULL) { 446 // lookup through the hierarchy for a method with matching name and sign. 447 super_method = instanceKlass::cast(k)->lookup_method(name, signature); 448 if (super_method == NULL) { 449 break; // we still have to search for a matching miranda method 450 } 451 // get the class holding the matching method 452 // make sure you use that class for is_override 453 instanceKlass* superk = instanceKlass::cast(super_method->method_holder()); 454 // we want only instance method matches 455 // pretend private methods are not in the super vtable 456 // since we do override around them: e.g. a.m pub/b.m private/c.m pub, 457 // ignore private, c.m pub does override a.m pub 458 // For classes that were not javac'd together, we also do transitive overriding around 459 // methods that have less accessibility 460 if ((!super_method->is_static()) && 461 (!super_method->is_private())) { 462 if (superk->is_override(super_method, classloader, classname, THREAD)) { 463 return false; 464 // else keep looking for transitive overrides 465 } 466 } 467 468 // Start with lookup result and continue to search up 469 k = superk->super(); // haven't found an override match yet; continue to look 470 } 471 472 // if the target method is public or protected it may have a matching 473 // miranda method in the super, whose entry it should re-use. 474 // Actually, to handle cases that javac would not generate, we need 475 // this check for all access permissions. 476 instanceKlass *sk = instanceKlass::cast(super); 477 if (sk->has_miranda_methods()) { 478 if (sk->lookup_method_in_all_interfaces(name, signature) != NULL) { 479 return false; // found a matching miranda; we do not need a new entry 480 } 481 } 482 return true; // found no match; we need a new entry 483 } 484 485 // Support for miranda methods 486 487 // get the vtable index of a miranda method with matching "name" and "signature" 488 int klassVtable::index_of_miranda(symbolOop name, symbolOop signature) { 489 // search from the bottom, might be faster 490 for (int i = (length() - 1); i >= 0; i--) { 491 methodOop m = table()[i].method(); 492 if (is_miranda_entry_at(i) && 493 m->name() == name && m->signature() == signature) { 494 return i; 495 } 496 } 497 return methodOopDesc::invalid_vtable_index; 498 } 499 500 // check if an entry is miranda 501 bool klassVtable::is_miranda_entry_at(int i) { 502 methodOop m = method_at(i); 503 klassOop method_holder = m->method_holder(); 504 instanceKlass *mhk = instanceKlass::cast(method_holder); 505 506 // miranda methods are interface methods in a class's vtable 507 if (mhk->is_interface()) { 508 assert(m->is_public() && m->is_abstract(), "should be public and abstract"); 509 assert(ik()->implements_interface(method_holder) , "this class should implement the interface"); 510 assert(is_miranda(m, ik()->methods(), ik()->super()), "should be a miranda_method"); 511 return true; 512 } 513 return false; 514 } 515 516 // check if a method is a miranda method, given a class's methods table and it's super 517 // the caller must make sure that the method belongs to an interface implemented by the class 518 bool klassVtable::is_miranda(methodOop m, objArrayOop class_methods, klassOop super) { 519 symbolOop name = m->name(); 520 symbolOop signature = m->signature(); 521 if (instanceKlass::find_method(class_methods, name, signature) == NULL) { 522 // did not find it in the method table of the current class 523 if (super == NULL) { 524 // super doesn't exist 525 return true; 526 } else { 527 if (instanceKlass::cast(super)->lookup_method(name, signature) == NULL) { 528 // super class hierarchy does not implement it 529 return true; 530 } 531 } 532 } 533 return false; 534 } 535 536 void klassVtable::add_new_mirandas_to_list(GrowableArray<methodOop>* list_of_current_mirandas, 537 objArrayOop current_interface_methods, 538 objArrayOop class_methods, 539 klassOop super) { 540 // iterate thru the current interface's method to see if it a miranda 541 int num_methods = current_interface_methods->length(); 542 for (int i = 0; i < num_methods; i++) { 543 methodOop im = methodOop(current_interface_methods->obj_at(i)); 544 bool is_duplicate = false; 545 int num_of_current_mirandas = list_of_current_mirandas->length(); 546 // check for duplicate mirandas in different interfaces we implement 547 for (int j = 0; j < num_of_current_mirandas; j++) { 548 methodOop miranda = list_of_current_mirandas->at(j); 549 if ((im->name() == miranda->name()) && 550 (im->signature() == miranda->signature())) { 551 is_duplicate = true; 552 break; 553 } 554 } 555 556 if (!is_duplicate) { // we don't want duplicate miranda entries in the vtable 557 if (is_miranda(im, class_methods, super)) { // is it a miranda at all? 558 instanceKlass *sk = instanceKlass::cast(super); 559 // check if it is a duplicate of a super's miranda 560 if (sk->lookup_method_in_all_interfaces(im->name(), im->signature()) == NULL) { 561 list_of_current_mirandas->append(im); 562 } 563 } 564 } 565 } 566 } 567 568 void klassVtable::get_mirandas(GrowableArray<methodOop>* mirandas, 569 klassOop super, objArrayOop class_methods, 570 objArrayOop local_interfaces) { 571 assert((mirandas->length() == 0) , "current mirandas must be 0"); 572 573 // iterate thru the local interfaces looking for a miranda 574 int num_local_ifs = local_interfaces->length(); 575 for (int i = 0; i < num_local_ifs; i++) { 576 instanceKlass *ik = instanceKlass::cast(klassOop(local_interfaces->obj_at(i))); 577 add_new_mirandas_to_list(mirandas, ik->methods(), class_methods, super); 578 // iterate thru each local's super interfaces 579 objArrayOop super_ifs = ik->transitive_interfaces(); 580 int num_super_ifs = super_ifs->length(); 581 for (int j = 0; j < num_super_ifs; j++) { 582 instanceKlass *sik = instanceKlass::cast(klassOop(super_ifs->obj_at(j))); 583 add_new_mirandas_to_list(mirandas, sik->methods(), class_methods, super); 584 } 585 } 586 } 587 588 // get number of mirandas 589 int klassVtable::get_num_mirandas(klassOop super, objArrayOop class_methods, objArrayOop local_interfaces) { 590 ResourceMark rm; 591 GrowableArray<methodOop>* mirandas = new GrowableArray<methodOop>(20); 592 get_mirandas(mirandas, super, class_methods, local_interfaces); 593 return mirandas->length(); 594 } 595 596 // fill in mirandas 597 void klassVtable::fill_in_mirandas(int& initialized) { 598 ResourceMark rm; 599 GrowableArray<methodOop>* mirandas = new GrowableArray<methodOop>(20); 600 instanceKlass *this_ik = ik(); 601 get_mirandas(mirandas, this_ik->super(), this_ik->methods(), this_ik->local_interfaces()); 602 int num_mirandas = mirandas->length(); 603 for (int i = 0; i < num_mirandas; i++) { 604 put_method_at(mirandas->at(i), initialized); 605 initialized++; 606 } 607 } 608 609 void klassVtable::copy_vtable_to(vtableEntry* start) { 610 Copy::disjoint_words((HeapWord*)table(), (HeapWord*)start, _length * vtableEntry::size()); 611 } 612 613 void klassVtable::adjust_method_entries(methodOop* old_methods, methodOop* new_methods, 614 int methods_length, bool * trace_name_printed) { 615 // search the vtable for uses of either obsolete or EMCP methods 616 for (int j = 0; j < methods_length; j++) { 617 methodOop old_method = old_methods[j]; 618 methodOop new_method = new_methods[j]; 619 620 // In the vast majority of cases we could get the vtable index 621 // by using: old_method->vtable_index() 622 // However, there are rare cases, eg. sun.awt.X11.XDecoratedPeer.getX() 623 // in sun.awt.X11.XFramePeer where methods occur more than once in the 624 // vtable, so, alas, we must do an exhaustive search. 625 for (int index = 0; index < length(); index++) { 626 if (unchecked_method_at(index) == old_method) { 627 put_method_at(new_method, index); 628 629 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 630 if (!(*trace_name_printed)) { 631 // RC_TRACE_MESG macro has an embedded ResourceMark 632 RC_TRACE_MESG(("adjust: name=%s", 633 Klass::cast(old_method->method_holder())->external_name())); 634 *trace_name_printed = true; 635 } 636 // RC_TRACE macro has an embedded ResourceMark 637 RC_TRACE(0x00100000, ("vtable method update: %s(%s)", 638 new_method->name()->as_C_string(), 639 new_method->signature()->as_C_string())); 640 } 641 } 642 } 643 } 644 } 645 646 647 // Garbage collection 648 void klassVtable::oop_follow_contents() { 649 int len = length(); 650 for (int i = 0; i < len; i++) { 651 MarkSweep::mark_and_push(adr_method_at(i)); 652 } 653 } 654 655 #ifndef SERIALGC 656 void klassVtable::oop_follow_contents(ParCompactionManager* cm) { 657 int len = length(); 658 for (int i = 0; i < len; i++) { 659 PSParallelCompact::mark_and_push(cm, adr_method_at(i)); 660 } 661 } 662 #endif // SERIALGC 663 664 void klassVtable::oop_adjust_pointers() { 665 int len = length(); 666 for (int i = 0; i < len; i++) { 667 MarkSweep::adjust_pointer(adr_method_at(i)); 668 } 669 } 670 671 #ifndef SERIALGC 672 void klassVtable::oop_update_pointers(ParCompactionManager* cm) { 673 const int n = length(); 674 for (int i = 0; i < n; i++) { 675 PSParallelCompact::adjust_pointer(adr_method_at(i)); 676 } 677 } 678 679 void klassVtable::oop_update_pointers(ParCompactionManager* cm, 680 HeapWord* beg_addr, HeapWord* end_addr) { 681 const int n = length(); 682 const int entry_size = vtableEntry::size(); 683 684 int beg_idx = 0; 685 HeapWord* const method_0 = (HeapWord*)adr_method_at(0); 686 if (beg_addr > method_0) { 687 // it's safe to use cast, as we have guarantees on vtable size to be sane 688 beg_idx = int((pointer_delta(beg_addr, method_0) + entry_size - 1) / entry_size); 689 } 690 691 oop* const beg_oop = adr_method_at(beg_idx); 692 oop* const end_oop = MIN2((oop*)end_addr, adr_method_at(n)); 693 for (oop* cur_oop = beg_oop; cur_oop < end_oop; cur_oop += entry_size) { 694 PSParallelCompact::adjust_pointer(cur_oop); 695 } 696 } 697 #endif // SERIALGC 698 699 // Iterators 700 void klassVtable::oop_oop_iterate(OopClosure* blk) { 701 int len = length(); 702 for (int i = 0; i < len; i++) { 703 blk->do_oop(adr_method_at(i)); 704 } 705 } 706 707 void klassVtable::oop_oop_iterate_m(OopClosure* blk, MemRegion mr) { 708 int len = length(); 709 int i; 710 for (i = 0; i < len; i++) { 711 if ((HeapWord*)adr_method_at(i) >= mr.start()) break; 712 } 713 for (; i < len; i++) { 714 oop* adr = adr_method_at(i); 715 if ((HeapWord*)adr < mr.end()) blk->do_oop(adr); 716 } 717 } 718 719 //----------------------------------------------------------------------------------------- 720 // Itable code 721 722 // Initialize a itableMethodEntry 723 void itableMethodEntry::initialize(methodOop m) { 724 if (m == NULL) return; 725 726 _method = m; 727 } 728 729 klassItable::klassItable(instanceKlassHandle klass) { 730 _klass = klass; 731 732 if (klass->itable_length() > 0) { 733 itableOffsetEntry* offset_entry = (itableOffsetEntry*)klass->start_of_itable(); 734 if (offset_entry != NULL && offset_entry->interface_klass() != NULL) { // Check that itable is initialized 735 // First offset entry points to the first method_entry 736 intptr_t* method_entry = (intptr_t *)(((address)klass->as_klassOop()) + offset_entry->offset()); 737 intptr_t* end = klass->end_of_itable(); 738 739 _table_offset = (intptr_t*)offset_entry - (intptr_t*)klass->as_klassOop(); 740 _size_offset_table = (method_entry - ((intptr_t*)offset_entry)) / itableOffsetEntry::size(); 741 _size_method_table = (end - method_entry) / itableMethodEntry::size(); 742 assert(_table_offset >= 0 && _size_offset_table >= 0 && _size_method_table >= 0, "wrong computation"); 743 return; 744 } 745 } 746 747 // The length of the itable was either zero, or it has not yet been initialized. 748 _table_offset = 0; 749 _size_offset_table = 0; 750 _size_method_table = 0; 751 } 752 753 // Garbage Collection 754 755 void klassItable::oop_follow_contents() { 756 // offset table 757 itableOffsetEntry* ioe = offset_entry(0); 758 for(int i = 0; i < _size_offset_table; i++) { 759 MarkSweep::mark_and_push((oop*)&ioe->_interface); 760 ioe++; 761 } 762 763 // method table 764 itableMethodEntry* ime = method_entry(0); 765 for(int j = 0; j < _size_method_table; j++) { 766 MarkSweep::mark_and_push((oop*)&ime->_method); 767 ime++; 768 } 769 } 770 771 #ifndef SERIALGC 772 void klassItable::oop_follow_contents(ParCompactionManager* cm) { 773 // offset table 774 itableOffsetEntry* ioe = offset_entry(0); 775 for(int i = 0; i < _size_offset_table; i++) { 776 PSParallelCompact::mark_and_push(cm, (oop*)&ioe->_interface); 777 ioe++; 778 } 779 780 // method table 781 itableMethodEntry* ime = method_entry(0); 782 for(int j = 0; j < _size_method_table; j++) { 783 PSParallelCompact::mark_and_push(cm, (oop*)&ime->_method); 784 ime++; 785 } 786 } 787 #endif // SERIALGC 788 789 void klassItable::oop_adjust_pointers() { 790 // offset table 791 itableOffsetEntry* ioe = offset_entry(0); 792 for(int i = 0; i < _size_offset_table; i++) { 793 MarkSweep::adjust_pointer((oop*)&ioe->_interface); 794 ioe++; 795 } 796 797 // method table 798 itableMethodEntry* ime = method_entry(0); 799 for(int j = 0; j < _size_method_table; j++) { 800 MarkSweep::adjust_pointer((oop*)&ime->_method); 801 ime++; 802 } 803 } 804 805 #ifndef SERIALGC 806 void klassItable::oop_update_pointers(ParCompactionManager* cm) { 807 // offset table 808 itableOffsetEntry* ioe = offset_entry(0); 809 for(int i = 0; i < _size_offset_table; i++) { 810 PSParallelCompact::adjust_pointer((oop*)&ioe->_interface); 811 ioe++; 812 } 813 814 // method table 815 itableMethodEntry* ime = method_entry(0); 816 for(int j = 0; j < _size_method_table; j++) { 817 PSParallelCompact::adjust_pointer((oop*)&ime->_method); 818 ime++; 819 } 820 } 821 822 void klassItable::oop_update_pointers(ParCompactionManager* cm, 823 HeapWord* beg_addr, HeapWord* end_addr) { 824 // offset table 825 itableOffsetEntry* ioe = offset_entry(0); 826 for(int i = 0; i < _size_offset_table; i++) { 827 oop* p = (oop*)&ioe->_interface; 828 PSParallelCompact::adjust_pointer(p, beg_addr, end_addr); 829 ioe++; 830 } 831 832 // method table 833 itableMethodEntry* ime = method_entry(0); 834 for(int j = 0; j < _size_method_table; j++) { 835 oop* p = (oop*)&ime->_method; 836 PSParallelCompact::adjust_pointer(p, beg_addr, end_addr); 837 ime++; 838 } 839 } 840 #endif // SERIALGC 841 842 // Iterators 843 void klassItable::oop_oop_iterate(OopClosure* blk) { 844 // offset table 845 itableOffsetEntry* ioe = offset_entry(0); 846 for(int i = 0; i < _size_offset_table; i++) { 847 blk->do_oop((oop*)&ioe->_interface); 848 ioe++; 849 } 850 851 // method table 852 itableMethodEntry* ime = method_entry(0); 853 for(int j = 0; j < _size_method_table; j++) { 854 blk->do_oop((oop*)&ime->_method); 855 ime++; 856 } 857 } 858 859 void klassItable::oop_oop_iterate_m(OopClosure* blk, MemRegion mr) { 860 // offset table 861 itableOffsetEntry* ioe = offset_entry(0); 862 for(int i = 0; i < _size_offset_table; i++) { 863 oop* adr = (oop*)&ioe->_interface; 864 if (mr.contains(adr)) blk->do_oop(adr); 865 ioe++; 866 } 867 868 // method table 869 itableMethodEntry* ime = method_entry(0); 870 for(int j = 0; j < _size_method_table; j++) { 871 oop* adr = (oop*)&ime->_method; 872 if (mr.contains(adr)) blk->do_oop(adr); 873 ime++; 874 } 875 } 876 877 878 static int initialize_count = 0; 879 880 // Initialization 881 void klassItable::initialize_itable(bool checkconstraints, TRAPS) { 882 // Cannot be setup doing bootstrapping, interfaces don't have 883 // itables, and klass with only ones entry have empty itables 884 if (Universe::is_bootstrapping() || 885 _klass->is_interface() || 886 _klass->itable_length() == itableOffsetEntry::size()) return; 887 888 // There's alway an extra itable entry so we can null-terminate it. 889 guarantee(size_offset_table() >= 1, "too small"); 890 int num_interfaces = size_offset_table() - 1; 891 if (num_interfaces > 0) { 892 if (TraceItables) tty->print_cr("%3d: Initializing itables for %s", ++initialize_count, 893 _klass->name()->as_C_string()); 894 895 896 // Iterate through all interfaces 897 int i; 898 for(i = 0; i < num_interfaces; i++) { 899 itableOffsetEntry* ioe = offset_entry(i); 900 KlassHandle interf_h (THREAD, ioe->interface_klass()); 901 assert(interf_h() != NULL && ioe->offset() != 0, "bad offset entry in itable"); 902 initialize_itable_for_interface(ioe->offset(), interf_h, checkconstraints, CHECK); 903 } 904 905 } 906 // Check that the last entry is empty 907 itableOffsetEntry* ioe = offset_entry(size_offset_table() - 1); 908 guarantee(ioe->interface_klass() == NULL && ioe->offset() == 0, "terminator entry missing"); 909 } 910 911 912 void klassItable::initialize_itable_for_interface(int method_table_offset, KlassHandle interf_h, bool checkconstraints, TRAPS) { 913 objArrayHandle methods(THREAD, instanceKlass::cast(interf_h())->methods()); 914 int nof_methods = methods()->length(); 915 HandleMark hm; 916 KlassHandle klass = _klass; 917 assert(nof_methods > 0, "at least one method must exist for interface to be in vtable"); 918 Handle interface_loader (THREAD, instanceKlass::cast(interf_h())->class_loader()); 919 int ime_num = 0; 920 921 // Skip first methodOop if it is a class initializer 922 int i = ((methodOop)methods()->obj_at(0))->name() != vmSymbols::class_initializer_name() ? 0 : 1; 923 924 // m, method_name, method_signature, klass reset each loop so they 925 // don't need preserving across check_signature_loaders call 926 // methods needs a handle in case of gc from check_signature_loaders 927 for(; i < nof_methods; i++) { 928 methodOop m = (methodOop)methods()->obj_at(i); 929 symbolOop method_name = m->name(); 930 symbolOop method_signature = m->signature(); 931 932 // This is same code as in Linkresolver::lookup_instance_method_in_klasses 933 methodOop target = klass->uncached_lookup_method(method_name, method_signature); 934 while (target != NULL && target->is_static()) { 935 // continue with recursive lookup through the superclass 936 klassOop super = Klass::cast(target->method_holder())->super(); 937 target = (super == NULL) ? methodOop(NULL) : Klass::cast(super)->uncached_lookup_method(method_name, method_signature); 938 } 939 if (target == NULL || !target->is_public() || target->is_abstract()) { 940 // Entry do not resolve. Leave it empty 941 } else { 942 // Entry did resolve, check loader constraints before initializing 943 // if checkconstraints requested 944 methodHandle target_h (THREAD, target); // preserve across gc 945 if (checkconstraints) { 946 Handle method_holder_loader (THREAD, instanceKlass::cast(target->method_holder())->class_loader()); 947 if (method_holder_loader() != interface_loader()) { 948 ResourceMark rm(THREAD); 949 char* failed_type_name = 950 SystemDictionary::check_signature_loaders(method_signature, 951 method_holder_loader, 952 interface_loader, 953 true, CHECK); 954 if (failed_type_name != NULL) { 955 const char* msg = "loader constraint violation in interface " 956 "itable initialization: when resolving method \"%s\" the class" 957 " loader (instance of %s) of the current class, %s, " 958 "and the class loader (instance of %s) for interface " 959 "%s have different Class objects for the type %s " 960 "used in the signature"; 961 char* sig = target_h()->name_and_sig_as_C_string(); 962 const char* loader1 = SystemDictionary::loader_name(method_holder_loader()); 963 char* current = klass->name()->as_C_string(); 964 const char* loader2 = SystemDictionary::loader_name(interface_loader()); 965 char* iface = instanceKlass::cast(interf_h())->name()->as_C_string(); 966 size_t buflen = strlen(msg) + strlen(sig) + strlen(loader1) + 967 strlen(current) + strlen(loader2) + strlen(iface) + 968 strlen(failed_type_name); 969 char* buf = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, buflen); 970 jio_snprintf(buf, buflen, msg, sig, loader1, current, loader2, 971 iface, failed_type_name); 972 THROW_MSG(vmSymbols::java_lang_LinkageError(), buf); 973 } 974 } 975 } 976 977 // ime may have moved during GC so recalculate address 978 itableOffsetEntry::method_entry(_klass(), method_table_offset)[ime_num].initialize(target_h()); 979 } 980 // Progress to next entry 981 ime_num++; 982 } 983 } 984 985 // Update entry for specific methodOop 986 void klassItable::initialize_with_method(methodOop m) { 987 itableMethodEntry* ime = method_entry(0); 988 for(int i = 0; i < _size_method_table; i++) { 989 if (ime->method() == m) { 990 ime->initialize(m); 991 } 992 ime++; 993 } 994 } 995 996 void klassItable::adjust_method_entries(methodOop* old_methods, methodOop* new_methods, 997 int methods_length, bool * trace_name_printed) { 998 // search the itable for uses of either obsolete or EMCP methods 999 for (int j = 0; j < methods_length; j++) { 1000 methodOop old_method = old_methods[j]; 1001 methodOop new_method = new_methods[j]; 1002 itableMethodEntry* ime = method_entry(0); 1003 1004 // The itable can describe more than one interface and the same 1005 // method signature can be specified by more than one interface. 1006 // This means we have to do an exhaustive search to find all the 1007 // old_method references. 1008 for (int i = 0; i < _size_method_table; i++) { 1009 if (ime->method() == old_method) { 1010 ime->initialize(new_method); 1011 1012 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 1013 if (!(*trace_name_printed)) { 1014 // RC_TRACE_MESG macro has an embedded ResourceMark 1015 RC_TRACE_MESG(("adjust: name=%s", 1016 Klass::cast(old_method->method_holder())->external_name())); 1017 *trace_name_printed = true; 1018 } 1019 // RC_TRACE macro has an embedded ResourceMark 1020 RC_TRACE(0x00200000, ("itable method update: %s(%s)", 1021 new_method->name()->as_C_string(), 1022 new_method->signature()->as_C_string())); 1023 } 1024 break; 1025 } 1026 ime++; 1027 } 1028 } 1029 } 1030 1031 1032 // Setup 1033 class InterfaceVisiterClosure : public StackObj { 1034 public: 1035 virtual void doit(klassOop intf, int method_count) = 0; 1036 }; 1037 1038 // Visit all interfaces with at-least one method (excluding <clinit>) 1039 void visit_all_interfaces(objArrayOop transitive_intf, InterfaceVisiterClosure *blk) { 1040 // Handle array argument 1041 for(int i = 0; i < transitive_intf->length(); i++) { 1042 klassOop intf = (klassOop)transitive_intf->obj_at(i); 1043 assert(Klass::cast(intf)->is_interface(), "sanity check"); 1044 1045 // Find no. of methods excluding a <clinit> 1046 int method_count = instanceKlass::cast(intf)->methods()->length(); 1047 if (method_count > 0) { 1048 methodOop m = (methodOop)instanceKlass::cast(intf)->methods()->obj_at(0); 1049 assert(m != NULL && m->is_method(), "sanity check"); 1050 if (m->name() == vmSymbols::object_initializer_name()) { 1051 method_count--; 1052 } 1053 } 1054 1055 // Only count interfaces with at least one method 1056 if (method_count > 0) { 1057 blk->doit(intf, method_count); 1058 } 1059 } 1060 } 1061 1062 class CountInterfacesClosure : public InterfaceVisiterClosure { 1063 private: 1064 int _nof_methods; 1065 int _nof_interfaces; 1066 public: 1067 CountInterfacesClosure() { _nof_methods = 0; _nof_interfaces = 0; } 1068 1069 int nof_methods() const { return _nof_methods; } 1070 int nof_interfaces() const { return _nof_interfaces; } 1071 1072 void doit(klassOop intf, int method_count) { _nof_methods += method_count; _nof_interfaces++; } 1073 }; 1074 1075 class SetupItableClosure : public InterfaceVisiterClosure { 1076 private: 1077 itableOffsetEntry* _offset_entry; 1078 itableMethodEntry* _method_entry; 1079 address _klass_begin; 1080 public: 1081 SetupItableClosure(address klass_begin, itableOffsetEntry* offset_entry, itableMethodEntry* method_entry) { 1082 _klass_begin = klass_begin; 1083 _offset_entry = offset_entry; 1084 _method_entry = method_entry; 1085 } 1086 1087 itableMethodEntry* method_entry() const { return _method_entry; } 1088 1089 void doit(klassOop intf, int method_count) { 1090 int offset = ((address)_method_entry) - _klass_begin; 1091 _offset_entry->initialize(intf, offset); 1092 _offset_entry++; 1093 _method_entry += method_count; 1094 } 1095 }; 1096 1097 int klassItable::compute_itable_size(objArrayHandle transitive_interfaces) { 1098 // Count no of interfaces and total number of interface methods 1099 CountInterfacesClosure cic; 1100 visit_all_interfaces(transitive_interfaces(), &cic); 1101 1102 // There's alway an extra itable entry so we can null-terminate it. 1103 int itable_size = calc_itable_size(cic.nof_interfaces() + 1, cic.nof_methods()); 1104 1105 // Statistics 1106 update_stats(itable_size * HeapWordSize); 1107 1108 return itable_size; 1109 } 1110 1111 1112 // Fill out offset table and interface klasses into the itable space 1113 void klassItable::setup_itable_offset_table(instanceKlassHandle klass) { 1114 if (klass->itable_length() == 0) return; 1115 assert(!klass->is_interface(), "Should have zero length itable"); 1116 1117 // Count no of interfaces and total number of interface methods 1118 CountInterfacesClosure cic; 1119 visit_all_interfaces(klass->transitive_interfaces(), &cic); 1120 int nof_methods = cic.nof_methods(); 1121 int nof_interfaces = cic.nof_interfaces(); 1122 1123 // Add one extra entry so we can null-terminate the table 1124 nof_interfaces++; 1125 1126 assert(compute_itable_size(objArrayHandle(klass->transitive_interfaces())) == 1127 calc_itable_size(nof_interfaces, nof_methods), 1128 "mismatch calculation of itable size"); 1129 1130 // Fill-out offset table 1131 itableOffsetEntry* ioe = (itableOffsetEntry*)klass->start_of_itable(); 1132 itableMethodEntry* ime = (itableMethodEntry*)(ioe + nof_interfaces); 1133 intptr_t* end = klass->end_of_itable(); 1134 assert((oop*)(ime + nof_methods) <= (oop*)klass->start_of_static_fields(), "wrong offset calculation (1)"); 1135 assert((oop*)(end) == (oop*)(ime + nof_methods), "wrong offset calculation (2)"); 1136 1137 // Visit all interfaces and initialize itable offset table 1138 SetupItableClosure sic((address)klass->as_klassOop(), ioe, ime); 1139 visit_all_interfaces(klass->transitive_interfaces(), &sic); 1140 1141 #ifdef ASSERT 1142 ime = sic.method_entry(); 1143 oop* v = (oop*) klass->end_of_itable(); 1144 assert( (oop*)(ime) == v, "wrong offset calculation (2)"); 1145 #endif 1146 } 1147 1148 1149 // m must be a method in an interface 1150 int klassItable::compute_itable_index(methodOop m) { 1151 klassOop intf = m->method_holder(); 1152 assert(instanceKlass::cast(intf)->is_interface(), "sanity check"); 1153 objArrayOop methods = instanceKlass::cast(intf)->methods(); 1154 int index = 0; 1155 while(methods->obj_at(index) != m) { 1156 index++; 1157 assert(index < methods->length(), "should find index for resolve_invoke"); 1158 } 1159 // Adjust for <clinit>, which is left out of table if first method 1160 if (methods->length() > 0 && ((methodOop)methods->obj_at(0))->name() == vmSymbols::class_initializer_name()) { 1161 index--; 1162 } 1163 return index; 1164 } 1165 1166 1167 // inverse to compute_itable_index 1168 methodOop klassItable::method_for_itable_index(klassOop intf, int itable_index) { 1169 assert(instanceKlass::cast(intf)->is_interface(), "sanity check"); 1170 objArrayOop methods = instanceKlass::cast(intf)->methods(); 1171 1172 int index = itable_index; 1173 // Adjust for <clinit>, which is left out of table if first method 1174 if (methods->length() > 0 && ((methodOop)methods->obj_at(0))->name() == vmSymbols::class_initializer_name()) { 1175 index++; 1176 } 1177 1178 if (itable_index < 0 || index >= methods->length()) 1179 return NULL; // help caller defend against bad indexes 1180 1181 methodOop m = (methodOop)methods->obj_at(index); 1182 assert(compute_itable_index(m) == itable_index, "correct inverse"); 1183 1184 return m; 1185 } 1186 1187 void klassVtable::verify(outputStream* st, bool forced) { 1188 // make sure table is initialized 1189 if (!Universe::is_fully_initialized()) return; 1190 #ifndef PRODUCT 1191 // avoid redundant verifies 1192 if (!forced && _verify_count == Universe::verify_count()) return; 1193 _verify_count = Universe::verify_count(); 1194 #endif 1195 oop* end_of_obj = (oop*)_klass() + _klass()->size(); 1196 oop* end_of_vtable = (oop *)&table()[_length]; 1197 if (end_of_vtable > end_of_obj) { 1198 fatal(err_msg("klass %s: klass object too short (vtable extends beyond " 1199 "end)", _klass->internal_name())); 1200 } 1201 1202 for (int i = 0; i < _length; i++) table()[i].verify(this, st); 1203 // verify consistency with superKlass vtable 1204 klassOop super = _klass->super(); 1205 if (super != NULL) { 1206 instanceKlass* sk = instanceKlass::cast(super); 1207 klassVtable* vt = sk->vtable(); 1208 for (int i = 0; i < vt->length(); i++) { 1209 verify_against(st, vt, i); 1210 } 1211 } 1212 } 1213 1214 void klassVtable::verify_against(outputStream* st, klassVtable* vt, int index) { 1215 vtableEntry* vte = &vt->table()[index]; 1216 if (vte->method()->name() != table()[index].method()->name() || 1217 vte->method()->signature() != table()[index].method()->signature()) { 1218 fatal("mismatched name/signature of vtable entries"); 1219 } 1220 } 1221 1222 #ifndef PRODUCT 1223 void klassVtable::print() { 1224 ResourceMark rm; 1225 tty->print("klassVtable for klass %s (length %d):\n", _klass->internal_name(), length()); 1226 for (int i = 0; i < length(); i++) { 1227 table()[i].print(); 1228 tty->cr(); 1229 } 1230 } 1231 #endif 1232 1233 void vtableEntry::verify(klassVtable* vt, outputStream* st) { 1234 NOT_PRODUCT(FlagSetting fs(IgnoreLockingAssertions, true)); 1235 assert(method() != NULL, "must have set method"); 1236 method()->verify(); 1237 // we sub_type, because it could be a miranda method 1238 if (!vt->klass()->is_subtype_of(method()->method_holder())) { 1239 #ifndef PRODUCT 1240 print(); 1241 #endif 1242 fatal(err_msg("vtableEntry " PTR_FORMAT ": method is from subclass", this)); 1243 } 1244 } 1245 1246 #ifndef PRODUCT 1247 1248 void vtableEntry::print() { 1249 ResourceMark rm; 1250 tty->print("vtableEntry %s: ", method()->name()->as_C_string()); 1251 if (Verbose) { 1252 tty->print("m %#lx ", (address)method()); 1253 } 1254 } 1255 1256 class VtableStats : AllStatic { 1257 public: 1258 static int no_klasses; // # classes with vtables 1259 static int no_array_klasses; // # array classes 1260 static int no_instance_klasses; // # instanceKlasses 1261 static int sum_of_vtable_len; // total # of vtable entries 1262 static int sum_of_array_vtable_len; // total # of vtable entries in array klasses only 1263 static int fixed; // total fixed overhead in bytes 1264 static int filler; // overhead caused by filler bytes 1265 static int entries; // total bytes consumed by vtable entries 1266 static int array_entries; // total bytes consumed by array vtable entries 1267 1268 static void do_class(klassOop k) { 1269 Klass* kl = k->klass_part(); 1270 klassVtable* vt = kl->vtable(); 1271 if (vt == NULL) return; 1272 no_klasses++; 1273 if (kl->oop_is_instance()) { 1274 no_instance_klasses++; 1275 kl->array_klasses_do(do_class); 1276 } 1277 if (kl->oop_is_array()) { 1278 no_array_klasses++; 1279 sum_of_array_vtable_len += vt->length(); 1280 } 1281 sum_of_vtable_len += vt->length(); 1282 } 1283 1284 static void compute() { 1285 SystemDictionary::classes_do(do_class); 1286 fixed = no_klasses * oopSize; // vtable length 1287 // filler size is a conservative approximation 1288 filler = oopSize * (no_klasses - no_instance_klasses) * (sizeof(instanceKlass) - sizeof(arrayKlass) - 1); 1289 entries = sizeof(vtableEntry) * sum_of_vtable_len; 1290 array_entries = sizeof(vtableEntry) * sum_of_array_vtable_len; 1291 } 1292 }; 1293 1294 int VtableStats::no_klasses = 0; 1295 int VtableStats::no_array_klasses = 0; 1296 int VtableStats::no_instance_klasses = 0; 1297 int VtableStats::sum_of_vtable_len = 0; 1298 int VtableStats::sum_of_array_vtable_len = 0; 1299 int VtableStats::fixed = 0; 1300 int VtableStats::filler = 0; 1301 int VtableStats::entries = 0; 1302 int VtableStats::array_entries = 0; 1303 1304 void klassVtable::print_statistics() { 1305 ResourceMark rm; 1306 HandleMark hm; 1307 VtableStats::compute(); 1308 tty->print_cr("vtable statistics:"); 1309 tty->print_cr("%6d classes (%d instance, %d array)", VtableStats::no_klasses, VtableStats::no_instance_klasses, VtableStats::no_array_klasses); 1310 int total = VtableStats::fixed + VtableStats::filler + VtableStats::entries; 1311 tty->print_cr("%6d bytes fixed overhead (refs + vtable object header)", VtableStats::fixed); 1312 tty->print_cr("%6d bytes filler overhead", VtableStats::filler); 1313 tty->print_cr("%6d bytes for vtable entries (%d for arrays)", VtableStats::entries, VtableStats::array_entries); 1314 tty->print_cr("%6d bytes total", total); 1315 } 1316 1317 bool klassVtable::check_no_old_entries() { 1318 // Check that there really is no entry 1319 for (int i = 0; i < length(); i++) { 1320 methodOop m = unchecked_method_at(i); 1321 if (m != NULL) { 1322 if (m->is_old()) { 1323 return false; 1324 } 1325 } 1326 } 1327 return true; 1328 } 1329 1330 void klassVtable::dump_vtable() { 1331 tty->print_cr("vtable dump --"); 1332 for (int i = 0; i < length(); i++) { 1333 methodOop m = unchecked_method_at(i); 1334 if (m != NULL) { 1335 tty->print(" (%5d) ", i); 1336 m->access_flags().print_on(tty); 1337 tty->print(" -- "); 1338 m->print_name(tty); 1339 tty->cr(); 1340 } 1341 } 1342 } 1343 1344 int klassItable::_total_classes; // Total no. of classes with itables 1345 long klassItable::_total_size; // Total no. of bytes used for itables 1346 1347 void klassItable::print_statistics() { 1348 tty->print_cr("itable statistics:"); 1349 tty->print_cr("%6d classes with itables", _total_classes); 1350 tty->print_cr("%6d K uses for itables (average by class: %d bytes)", _total_size / K, _total_size / _total_classes); 1351 } 1352 1353 #endif // PRODUCT