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