ciInstanceKlass.cpp revision 1472:c18cbe5936b8
1168515Sgshapiro/* 2261363Sgshapiro * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved. 3168515Sgshapiro * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4168515Sgshapiro * 5168515Sgshapiro * This code is free software; you can redistribute it and/or modify it 6168515Sgshapiro * under the terms of the GNU General Public License version 2 only, as 7168515Sgshapiro * published by the Free Software Foundation. 8168515Sgshapiro * 9261363Sgshapiro * This code is distributed in the hope that it will be useful, but WITHOUT 10168515Sgshapiro * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11168515Sgshapiro * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12168515Sgshapiro * version 2 for more details (a copy is included in the LICENSE file that 13168515Sgshapiro * accompanied this code). 14168515Sgshapiro * 15168515Sgshapiro * You should have received a copy of the GNU General Public License version 16168515Sgshapiro * 2 along with this work; if not, write to the Free Software Foundation, 17168515Sgshapiro * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18168515Sgshapiro * 19168515Sgshapiro * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20168515Sgshapiro * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25#include "incls/_precompiled.incl" 26#include "incls/_ciInstanceKlass.cpp.incl" 27 28// ciInstanceKlass 29// 30// This class represents a klassOop in the HotSpot virtual machine 31// whose Klass part in an instanceKlass. 32 33// ------------------------------------------------------------------ 34// ciInstanceKlass::ciInstanceKlass 35// 36// Loaded instance klass. 37ciInstanceKlass::ciInstanceKlass(KlassHandle h_k) : 38 ciKlass(h_k), _non_static_fields(NULL) 39{ 40 assert(get_Klass()->oop_is_instance(), "wrong type"); 41 instanceKlass* ik = get_instanceKlass(); 42 43 AccessFlags access_flags = ik->access_flags(); 44 _flags = ciFlags(access_flags); 45 _has_finalizer = access_flags.has_finalizer(); 46 _has_subklass = ik->subklass() != NULL; 47 _is_initialized = ik->is_initialized(); 48 // Next line must follow and use the result of the previous line: 49 _is_linked = _is_initialized || ik->is_linked(); 50 _nonstatic_field_size = ik->nonstatic_field_size(); 51 _has_nonstatic_fields = ik->has_nonstatic_fields(); 52 _nonstatic_fields = NULL; // initialized lazily by compute_nonstatic_fields: 53 54 _nof_implementors = ik->nof_implementors(); 55 for (int i = 0; i < implementors_limit; i++) { 56 _implementors[i] = NULL; // we will fill these lazily 57 } 58 59 Thread *thread = Thread::current(); 60 if (ciObjectFactory::is_initialized()) { 61 _loader = JNIHandles::make_local(thread, ik->class_loader()); 62 _protection_domain = JNIHandles::make_local(thread, 63 ik->protection_domain()); 64 _is_shared = false; 65 } else { 66 Handle h_loader(thread, ik->class_loader()); 67 Handle h_protection_domain(thread, ik->protection_domain()); 68 _loader = JNIHandles::make_global(h_loader); 69 _protection_domain = JNIHandles::make_global(h_protection_domain); 70 _is_shared = true; 71 } 72 73 // Lazy fields get filled in only upon request. 74 _super = NULL; 75 _java_mirror = NULL; 76 77 if (is_shared()) { 78 if (h_k() != SystemDictionary::Object_klass()) { 79 super(); 80 } 81 java_mirror(); 82 //compute_nonstatic_fields(); // done outside of constructor 83 } 84 85 _field_cache = NULL; 86} 87 88// Version for unloaded classes: 89ciInstanceKlass::ciInstanceKlass(ciSymbol* name, 90 jobject loader, jobject protection_domain) 91 : ciKlass(name, ciInstanceKlassKlass::make()) 92{ 93 assert(name->byte_at(0) != '[', "not an instance klass"); 94 _is_initialized = false; 95 _is_linked = false; 96 _nonstatic_field_size = -1; 97 _has_nonstatic_fields = false; 98 _nonstatic_fields = NULL; 99 _nof_implementors = -1; 100 _loader = loader; 101 _protection_domain = protection_domain; 102 _is_shared = false; 103 _super = NULL; 104 _java_mirror = NULL; 105 _field_cache = NULL; 106} 107 108 109 110// ------------------------------------------------------------------ 111// ciInstanceKlass::compute_shared_is_initialized 112bool ciInstanceKlass::compute_shared_is_initialized() { 113 GUARDED_VM_ENTRY( 114 instanceKlass* ik = get_instanceKlass(); 115 _is_initialized = ik->is_initialized(); 116 return _is_initialized; 117 ) 118} 119 120// ------------------------------------------------------------------ 121// ciInstanceKlass::compute_shared_is_linked 122bool ciInstanceKlass::compute_shared_is_linked() { 123 GUARDED_VM_ENTRY( 124 instanceKlass* ik = get_instanceKlass(); 125 _is_linked = ik->is_linked(); 126 return _is_linked; 127 ) 128} 129 130// ------------------------------------------------------------------ 131// ciInstanceKlass::compute_shared_has_subklass 132bool ciInstanceKlass::compute_shared_has_subklass() { 133 GUARDED_VM_ENTRY( 134 instanceKlass* ik = get_instanceKlass(); 135 _has_subklass = ik->subklass() != NULL; 136 return _has_subklass; 137 ) 138} 139 140// ------------------------------------------------------------------ 141// ciInstanceKlass::compute_shared_nof_implementors 142int ciInstanceKlass::compute_shared_nof_implementors() { 143 // We requery this property, since it is a very old ciObject. 144 GUARDED_VM_ENTRY( 145 instanceKlass* ik = get_instanceKlass(); 146 _nof_implementors = ik->nof_implementors(); 147 return _nof_implementors; 148 ) 149} 150 151// ------------------------------------------------------------------ 152// ciInstanceKlass::loader 153oop ciInstanceKlass::loader() { 154 ASSERT_IN_VM; 155 return JNIHandles::resolve(_loader); 156} 157 158// ------------------------------------------------------------------ 159// ciInstanceKlass::loader_handle 160jobject ciInstanceKlass::loader_handle() { 161 return _loader; 162} 163 164// ------------------------------------------------------------------ 165// ciInstanceKlass::protection_domain 166oop ciInstanceKlass::protection_domain() { 167 ASSERT_IN_VM; 168 return JNIHandles::resolve(_protection_domain); 169} 170 171// ------------------------------------------------------------------ 172// ciInstanceKlass::protection_domain_handle 173jobject ciInstanceKlass::protection_domain_handle() { 174 return _protection_domain; 175} 176 177// ------------------------------------------------------------------ 178// ciInstanceKlass::field_cache 179// 180// Get the field cache associated with this klass. 181ciConstantPoolCache* ciInstanceKlass::field_cache() { 182 if (is_shared()) { 183 return NULL; 184 } 185 if (_field_cache == NULL) { 186 assert(!is_java_lang_Object(), "Object has no fields"); 187 Arena* arena = CURRENT_ENV->arena(); 188 _field_cache = new (arena) ciConstantPoolCache(arena, 5); 189 } 190 return _field_cache; 191} 192 193// ------------------------------------------------------------------ 194// ciInstanceKlass::get_canonical_holder 195// 196ciInstanceKlass* ciInstanceKlass::get_canonical_holder(int offset) { 197 #ifdef ASSERT 198 if (!(offset >= 0 && offset < layout_helper())) { 199 tty->print("*** get_canonical_holder(%d) on ", offset); 200 this->print(); 201 tty->print_cr(" ***"); 202 }; 203 assert(offset >= 0 && offset < layout_helper(), "offset must be tame"); 204 #endif 205 206 if (offset < instanceOopDesc::base_offset_in_bytes()) { 207 // All header offsets belong properly to java/lang/Object. 208 return CURRENT_ENV->Object_klass(); 209 } 210 211 ciInstanceKlass* self = this; 212 for (;;) { 213 assert(self->is_loaded(), "must be loaded to have size"); 214 ciInstanceKlass* super = self->super(); 215 if (super == NULL || super->nof_nonstatic_fields() == 0 || 216 !super->contains_field_offset(offset)) { 217 return self; 218 } else { 219 self = super; // return super->get_canonical_holder(offset) 220 } 221 } 222} 223 224// ------------------------------------------------------------------ 225// ciInstanceKlass::is_java_lang_Object 226// 227// Is this klass java.lang.Object? 228bool ciInstanceKlass::is_java_lang_Object() { 229 return equals(CURRENT_ENV->Object_klass()); 230} 231 232// ------------------------------------------------------------------ 233// ciInstanceKlass::uses_default_loader 234bool ciInstanceKlass::uses_default_loader() { 235 // Note: We do not need to resolve the handle or enter the VM 236 // in order to test null-ness. 237 return _loader == NULL; 238} 239 240// ------------------------------------------------------------------ 241// ciInstanceKlass::is_in_package 242// 243// Is this klass in the given package? 244bool ciInstanceKlass::is_in_package(const char* packagename, int len) { 245 // To avoid class loader mischief, this test always rejects application classes. 246 if (!uses_default_loader()) 247 return false; 248 GUARDED_VM_ENTRY( 249 return is_in_package_impl(packagename, len); 250 ) 251} 252 253bool ciInstanceKlass::is_in_package_impl(const char* packagename, int len) { 254 ASSERT_IN_VM; 255 256 // If packagename contains trailing '/' exclude it from the 257 // prefix-test since we test for it explicitly. 258 if (packagename[len - 1] == '/') 259 len--; 260 261 if (!name()->starts_with(packagename, len)) 262 return false; 263 264 // Test if the class name is something like "java/lang". 265 if ((len + 1) > name()->utf8_length()) 266 return false; 267 268 // Test for trailing '/' 269 if ((char) name()->byte_at(len) != '/') 270 return false; 271 272 // Make sure it's not actually in a subpackage: 273 if (name()->index_of_at(len+1, "/", 1) >= 0) 274 return false; 275 276 return true; 277} 278 279// ------------------------------------------------------------------ 280// ciInstanceKlass::print_impl 281// 282// Implementation of the print method. 283void ciInstanceKlass::print_impl(outputStream* st) { 284 ciKlass::print_impl(st); 285 GUARDED_VM_ENTRY(st->print(" loader=0x%x", (address)loader());) 286 if (is_loaded()) { 287 st->print(" loaded=true initialized=%s finalized=%s subklass=%s size=%d flags=", 288 bool_to_str(is_initialized()), 289 bool_to_str(has_finalizer()), 290 bool_to_str(has_subklass()), 291 layout_helper()); 292 293 _flags.print_klass_flags(); 294 295 if (_super) { 296 st->print(" super="); 297 _super->print_name(); 298 } 299 if (_java_mirror) { 300 st->print(" mirror=PRESENT"); 301 } 302 } else { 303 st->print(" loaded=false"); 304 } 305} 306 307// ------------------------------------------------------------------ 308// ciInstanceKlass::super 309// 310// Get the superklass of this klass. 311ciInstanceKlass* ciInstanceKlass::super() { 312 assert(is_loaded(), "must be loaded"); 313 if (_super == NULL && !is_java_lang_Object()) { 314 GUARDED_VM_ENTRY( 315 klassOop super_klass = get_instanceKlass()->super(); 316 _super = CURRENT_ENV->get_object(super_klass)->as_instance_klass(); 317 ) 318 } 319 return _super; 320} 321 322// ------------------------------------------------------------------ 323// ciInstanceKlass::java_mirror 324// 325// Get the instance of java.lang.Class corresponding to this klass. 326ciInstance* ciInstanceKlass::java_mirror() { 327 assert(is_loaded(), "must be loaded"); 328 if (_java_mirror == NULL) { 329 _java_mirror = ciKlass::java_mirror(); 330 } 331 return _java_mirror; 332} 333 334// ------------------------------------------------------------------ 335// ciInstanceKlass::unique_concrete_subklass 336ciInstanceKlass* ciInstanceKlass::unique_concrete_subklass() { 337 if (!is_loaded()) return NULL; // No change if class is not loaded 338 if (!is_abstract()) return NULL; // Only applies to abstract classes. 339 if (!has_subklass()) return NULL; // Must have at least one subklass. 340 VM_ENTRY_MARK; 341 instanceKlass* ik = get_instanceKlass(); 342 Klass* up = ik->up_cast_abstract(); 343 assert(up->oop_is_instance(), "must be instanceKlass"); 344 if (ik == up) { 345 return NULL; 346 } 347 return CURRENT_THREAD_ENV->get_object(up->as_klassOop())->as_instance_klass(); 348} 349 350// ------------------------------------------------------------------ 351// ciInstanceKlass::has_finalizable_subclass 352bool ciInstanceKlass::has_finalizable_subclass() { 353 if (!is_loaded()) return true; 354 VM_ENTRY_MARK; 355 return Dependencies::find_finalizable_subclass(get_instanceKlass()) != NULL; 356} 357 358// ------------------------------------------------------------------ 359// ciInstanceKlass::get_field_by_offset 360ciField* ciInstanceKlass::get_field_by_offset(int field_offset, bool is_static) { 361 if (!is_static) { 362 for (int i = 0, len = nof_nonstatic_fields(); i < len; i++) { 363 ciField* field = _nonstatic_fields->at(i); 364 int field_off = field->offset_in_bytes(); 365 if (field_off == field_offset) 366 return field; 367 if (field_off > field_offset) 368 break; 369 // could do binary search or check bins, but probably not worth it 370 } 371 return NULL; 372 } 373 VM_ENTRY_MARK; 374 instanceKlass* k = get_instanceKlass(); 375 fieldDescriptor fd; 376 if (!k->find_field_from_offset(field_offset, is_static, &fd)) { 377 return NULL; 378 } 379 ciField* field = new (CURRENT_THREAD_ENV->arena()) ciField(&fd); 380 return field; 381} 382 383// ------------------------------------------------------------------ 384// ciInstanceKlass::get_field_by_name 385ciField* ciInstanceKlass::get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static) { 386 VM_ENTRY_MARK; 387 instanceKlass* k = get_instanceKlass(); 388 fieldDescriptor fd; 389 klassOop def = k->find_field(name->get_symbolOop(), signature->get_symbolOop(), is_static, &fd); 390 if (def == NULL) { 391 return NULL; 392 } 393 ciField* field = new (CURRENT_THREAD_ENV->arena()) ciField(&fd); 394 return field; 395} 396 397// ------------------------------------------------------------------ 398// ciInstanceKlass::non_static_fields. 399 400class NonStaticFieldFiller: public FieldClosure { 401 GrowableArray<ciField*>* _arr; 402 ciEnv* _curEnv; 403public: 404 NonStaticFieldFiller(ciEnv* curEnv, GrowableArray<ciField*>* arr) : 405 _curEnv(curEnv), _arr(arr) 406 {} 407 void do_field(fieldDescriptor* fd) { 408 ciField* field = new (_curEnv->arena()) ciField(fd); 409 _arr->append(field); 410 } 411}; 412 413GrowableArray<ciField*>* ciInstanceKlass::non_static_fields() { 414 if (_non_static_fields == NULL) { 415 VM_ENTRY_MARK; 416 ciEnv* curEnv = ciEnv::current(); 417 instanceKlass* ik = get_instanceKlass(); 418 int max_n_fields = ik->fields()->length()/instanceKlass::next_offset; 419 420 _non_static_fields = 421 new (curEnv->arena()) GrowableArray<ciField*>(max_n_fields); 422 NonStaticFieldFiller filler(curEnv, _non_static_fields); 423 ik->do_nonstatic_fields(&filler); 424 } 425 return _non_static_fields; 426} 427 428static int sort_field_by_offset(ciField** a, ciField** b) { 429 return (*a)->offset_in_bytes() - (*b)->offset_in_bytes(); 430 // (no worries about 32-bit overflow...) 431} 432 433// ------------------------------------------------------------------ 434// ciInstanceKlass::compute_nonstatic_fields 435int ciInstanceKlass::compute_nonstatic_fields() { 436 assert(is_loaded(), "must be loaded"); 437 438 if (_nonstatic_fields != NULL) 439 return _nonstatic_fields->length(); 440 441 if (!has_nonstatic_fields()) { 442 Arena* arena = CURRENT_ENV->arena(); 443 _nonstatic_fields = new (arena) GrowableArray<ciField*>(arena, 0, 0, NULL); 444 return 0; 445 } 446 assert(!is_java_lang_Object(), "bootstrap OK"); 447 448 // Size in bytes of my fields, including inherited fields. 449 int fsize = nonstatic_field_size() * heapOopSize; 450 451 ciInstanceKlass* super = this->super(); 452 GrowableArray<ciField*>* super_fields = NULL; 453 if (super != NULL && super->has_nonstatic_fields()) { 454 int super_fsize = super->nonstatic_field_size() * heapOopSize; 455 int super_flen = super->nof_nonstatic_fields(); 456 super_fields = super->_nonstatic_fields; 457 assert(super_flen == 0 || super_fields != NULL, "first get nof_fields"); 458 // See if I am no larger than my super; if so, I can use his fields. 459 if (fsize == super_fsize) { 460 _nonstatic_fields = super_fields; 461 return super_fields->length(); 462 } 463 } 464 465 GrowableArray<ciField*>* fields = NULL; 466 GUARDED_VM_ENTRY({ 467 fields = compute_nonstatic_fields_impl(super_fields); 468 }); 469 470 if (fields == NULL) { 471 // This can happen if this class (java.lang.Class) has invisible fields. 472 _nonstatic_fields = super_fields; 473 return super_fields->length(); 474 } 475 476 int flen = fields->length(); 477 478 // Now sort them by offset, ascending. 479 // (In principle, they could mix with superclass fields.) 480 fields->sort(sort_field_by_offset); 481#ifdef ASSERT 482 int last_offset = instanceOopDesc::base_offset_in_bytes(); 483 for (int i = 0; i < fields->length(); i++) { 484 ciField* field = fields->at(i); 485 int offset = field->offset_in_bytes(); 486 int size = (field->_type == NULL) ? heapOopSize : field->size_in_bytes(); 487 assert(last_offset <= offset, "no field overlap"); 488 if (last_offset > (int)sizeof(oopDesc)) 489 assert((offset - last_offset) < BytesPerLong, "no big holes"); 490 // Note: Two consecutive T_BYTE fields will be separated by wordSize-1 491 // padding bytes if one of them is declared by a superclass. 492 // This is a minor inefficiency classFileParser.cpp. 493 last_offset = offset + size; 494 } 495 assert(last_offset <= (int)instanceOopDesc::base_offset_in_bytes() + fsize, "no overflow"); 496#endif 497 498 _nonstatic_fields = fields; 499 return flen; 500} 501 502GrowableArray<ciField*>* 503ciInstanceKlass::compute_nonstatic_fields_impl(GrowableArray<ciField*>* 504 super_fields) { 505 ASSERT_IN_VM; 506 Arena* arena = CURRENT_ENV->arena(); 507 int flen = 0; 508 GrowableArray<ciField*>* fields = NULL; 509 instanceKlass* k = get_instanceKlass(); 510 typeArrayOop fields_array = k->fields(); 511 for (int pass = 0; pass <= 1; pass++) { 512 for (int i = 0, alen = fields_array->length(); i < alen; i += instanceKlass::next_offset) { 513 fieldDescriptor fd; 514 fd.initialize(k->as_klassOop(), i); 515 if (fd.is_static()) continue; 516 if (pass == 0) { 517 flen += 1; 518 } else { 519 ciField* field = new (arena) ciField(&fd); 520 fields->append(field); 521 } 522 } 523 524 // Between passes, allocate the array: 525 if (pass == 0) { 526 if (flen == 0) { 527 return NULL; // return nothing if none are locally declared 528 } 529 if (super_fields != NULL) { 530 flen += super_fields->length(); 531 } 532 fields = new (arena) GrowableArray<ciField*>(arena, flen, 0, NULL); 533 if (super_fields != NULL) { 534 fields->appendAll(super_fields); 535 } 536 } 537 } 538 assert(fields->length() == flen, "sanity"); 539 return fields; 540} 541 542// ------------------------------------------------------------------ 543// ciInstanceKlass::find_method 544// 545// Find a method in this klass. 546ciMethod* ciInstanceKlass::find_method(ciSymbol* name, ciSymbol* signature) { 547 VM_ENTRY_MARK; 548 instanceKlass* k = get_instanceKlass(); 549 symbolOop name_sym = name->get_symbolOop(); 550 symbolOop sig_sym= signature->get_symbolOop(); 551 552 methodOop m = k->find_method(name_sym, sig_sym); 553 if (m == NULL) return NULL; 554 555 return CURRENT_THREAD_ENV->get_object(m)->as_method(); 556} 557 558// ------------------------------------------------------------------ 559// ciInstanceKlass::is_leaf_type 560bool ciInstanceKlass::is_leaf_type() { 561 assert(is_loaded(), "must be loaded"); 562 if (is_shared()) { 563 return is_final(); // approximately correct 564 } else { 565 return !_has_subklass && (_nof_implementors == 0); 566 } 567} 568 569// ------------------------------------------------------------------ 570// ciInstanceKlass::implementor 571// 572// Report an implementor of this interface. 573// Returns NULL if exact information is not available. 574// Note that there are various races here, since my copy 575// of _nof_implementors might be out of date with respect 576// to results returned by instanceKlass::implementor. 577// This is OK, since any dependencies we decide to assert 578// will be checked later under the Compile_lock. 579ciInstanceKlass* ciInstanceKlass::implementor(int n) { 580 if (n > implementors_limit) { 581 return NULL; 582 } 583 ciInstanceKlass* impl = _implementors[n]; 584 if (impl == NULL) { 585 if (_nof_implementors > implementors_limit) { 586 return NULL; 587 } 588 // Go into the VM to fetch the implementor. 589 { 590 VM_ENTRY_MARK; 591 klassOop k = get_instanceKlass()->implementor(n); 592 if (k != NULL) { 593 impl = CURRENT_THREAD_ENV->get_object(k)->as_instance_klass(); 594 } 595 } 596 // Memoize this result. 597 if (!is_shared()) { 598 _implementors[n] = (impl == NULL)? this: impl; 599 } 600 } else if (impl == this) { 601 impl = NULL; // memoized null result from a VM query 602 } 603 return impl; 604} 605