1 /* 2 * Copyright (c) 1997, 2012, 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/classLoader.hpp" 27 #include "classfile/javaClasses.hpp" 28 #include "classfile/symbolTable.hpp" 29 #include "classfile/systemDictionary.hpp" 30 #include "classfile/vmSymbols.hpp" 31 #include "code/codeCache.hpp" 32 #include "code/dependencies.hpp" 33 #include "gc_interface/collectedHeap.inline.hpp" 34 #include "interpreter/interpreter.hpp" 35 #include "memory/cardTableModRefBS.hpp" 36 #include "memory/filemap.hpp" 37 #include "memory/gcLocker.inline.hpp" 38 #include "memory/genCollectedHeap.hpp" 39 #include "memory/genRemSet.hpp" 40 #include "memory/generation.hpp" 41 #include "memory/oopFactory.hpp" 42 #include "memory/permGen.hpp" 43 #include "memory/space.hpp" 44 #include "memory/universe.hpp" 45 #include "memory/universe.inline.hpp" 46 #include "oops/arrayKlassKlass.hpp" 47 #include "oops/compiledICHolderKlass.hpp" 48 #include "oops/constMethodKlass.hpp" 49 #include "oops/constantPoolKlass.hpp" 50 #include "oops/constantPoolOop.hpp" 51 #include "oops/cpCacheKlass.hpp" 52 #include "oops/cpCacheOop.hpp" 53 #include "oops/instanceKlass.hpp" 54 #include "oops/instanceMirrorKlass.hpp" 55 #include "oops/instanceKlassKlass.hpp" 56 #include "oops/instanceRefKlass.hpp" 57 #include "oops/klassKlass.hpp" 58 #include "oops/klassOop.hpp" 59 #include "oops/methodDataKlass.hpp" 60 #include "oops/methodKlass.hpp" 61 #include "oops/objArrayKlassKlass.hpp" 62 #include "oops/oop.inline.hpp" 63 #include "oops/typeArrayKlass.hpp" 64 #include "oops/typeArrayKlassKlass.hpp" 65 #include "prims/jvmtiRedefineClassesTrace.hpp" 66 #include "runtime/aprofiler.hpp" 67 #include "runtime/arguments.hpp" 68 #include "runtime/deoptimization.hpp" 69 #include "runtime/fprofiler.hpp" 70 #include "runtime/handles.inline.hpp" 71 #include "runtime/init.hpp" 72 #include "runtime/java.hpp" 73 #include "runtime/javaCalls.hpp" 74 #include "runtime/sharedRuntime.hpp" 75 #include "runtime/synchronizer.hpp" 76 #include "runtime/timer.hpp" 77 #include "runtime/vm_operations.hpp" 78 #include "services/memoryService.hpp" 79 #include "utilities/copy.hpp" 80 #include "utilities/events.hpp" 81 #include "utilities/hashtable.inline.hpp" 82 #include "utilities/preserveException.hpp" 83 #ifdef TARGET_OS_FAMILY_linux 84 # include "thread_linux.inline.hpp" 85 #endif 86 #ifdef TARGET_OS_FAMILY_solaris 87 # include "thread_solaris.inline.hpp" 88 #endif 89 #ifdef TARGET_OS_FAMILY_windows 90 # include "thread_windows.inline.hpp" 91 #endif 92 #ifdef TARGET_OS_FAMILY_bsd 93 # include "thread_bsd.inline.hpp" 94 #endif 95 #ifndef SERIALGC 96 #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp" 97 #include "gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.hpp" 98 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" 99 #include "gc_implementation/g1/g1CollectorPolicy.hpp" 100 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp" 101 #endif 102 103 // Known objects 104 klassOop Universe::_boolArrayKlassObj = NULL; 105 klassOop Universe::_byteArrayKlassObj = NULL; 106 klassOop Universe::_charArrayKlassObj = NULL; 107 klassOop Universe::_intArrayKlassObj = NULL; 108 klassOop Universe::_shortArrayKlassObj = NULL; 109 klassOop Universe::_longArrayKlassObj = NULL; 110 klassOop Universe::_singleArrayKlassObj = NULL; 111 klassOop Universe::_doubleArrayKlassObj = NULL; 112 klassOop Universe::_typeArrayKlassObjs[T_VOID+1] = { NULL /*, NULL...*/ }; 113 klassOop Universe::_objectArrayKlassObj = NULL; 114 klassOop Universe::_methodKlassObj = NULL; 115 klassOop Universe::_constMethodKlassObj = NULL; 116 klassOop Universe::_methodDataKlassObj = NULL; 117 klassOop Universe::_klassKlassObj = NULL; 118 klassOop Universe::_arrayKlassKlassObj = NULL; 119 klassOop Universe::_objArrayKlassKlassObj = NULL; 120 klassOop Universe::_typeArrayKlassKlassObj = NULL; 121 klassOop Universe::_instanceKlassKlassObj = NULL; 122 klassOop Universe::_constantPoolKlassObj = NULL; 123 klassOop Universe::_constantPoolCacheKlassObj = NULL; 124 klassOop Universe::_compiledICHolderKlassObj = NULL; 125 klassOop Universe::_systemObjArrayKlassObj = NULL; 126 oop Universe::_int_mirror = NULL; 127 oop Universe::_float_mirror = NULL; 128 oop Universe::_double_mirror = NULL; 129 oop Universe::_byte_mirror = NULL; 130 oop Universe::_bool_mirror = NULL; 131 oop Universe::_char_mirror = NULL; 132 oop Universe::_long_mirror = NULL; 133 oop Universe::_short_mirror = NULL; 134 oop Universe::_void_mirror = NULL; 135 oop Universe::_mirrors[T_VOID+1] = { NULL /*, NULL...*/ }; 136 oop Universe::_main_thread_group = NULL; 137 oop Universe::_system_thread_group = NULL; 138 typeArrayOop Universe::_the_empty_byte_array = NULL; 139 typeArrayOop Universe::_the_empty_short_array = NULL; 140 typeArrayOop Universe::_the_empty_int_array = NULL; 141 objArrayOop Universe::_the_empty_system_obj_array = NULL; 142 objArrayOop Universe::_the_empty_class_klass_array = NULL; 143 objArrayOop Universe::_the_array_interfaces_array = NULL; 144 oop Universe::_the_null_string = NULL; 145 oop Universe::_the_min_jint_string = NULL; 146 LatestMethodOopCache* Universe::_finalizer_register_cache = NULL; 147 LatestMethodOopCache* Universe::_loader_addClass_cache = NULL; 148 ActiveMethodOopsCache* Universe::_reflect_invoke_cache = NULL; 149 oop Universe::_out_of_memory_error_java_heap = NULL; 150 oop Universe::_out_of_memory_error_perm_gen = NULL; 151 oop Universe::_out_of_memory_error_array_size = NULL; 152 oop Universe::_out_of_memory_error_gc_overhead_limit = NULL; 153 oop Universe::_primordial_loader_cache = NULL; 154 objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL; 155 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0; 156 bool Universe::_verify_in_progress = false; 157 oop Universe::_null_ptr_exception_instance = NULL; 158 oop Universe::_arithmetic_exception_instance = NULL; 159 oop Universe::_virtual_machine_error_instance = NULL; 160 oop Universe::_vm_exception = NULL; 161 162 // These variables are guarded by FullGCALot_lock. 163 debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;) 164 debug_only(int Universe::_fullgc_alot_dummy_next = 0;) 165 166 167 // Heap 168 int Universe::_verify_count = 0; 169 170 int Universe::_base_vtable_size = 0; 171 bool Universe::_bootstrapping = false; 172 bool Universe::_fully_initialized = false; 173 174 size_t Universe::_heap_capacity_at_last_gc; 175 size_t Universe::_heap_used_at_last_gc = 0; 176 177 CollectedHeap* Universe::_collectedHeap = NULL; 178 179 NarrowOopStruct Universe::_narrow_oop = { NULL, 0, true }; 180 181 182 void Universe::basic_type_classes_do(void f(klassOop)) { 183 f(boolArrayKlassObj()); 184 f(byteArrayKlassObj()); 185 f(charArrayKlassObj()); 186 f(intArrayKlassObj()); 187 f(shortArrayKlassObj()); 188 f(longArrayKlassObj()); 189 f(singleArrayKlassObj()); 190 f(doubleArrayKlassObj()); 191 } 192 193 194 void Universe::system_classes_do(void f(klassOop)) { 195 f(methodKlassObj()); 196 f(constMethodKlassObj()); 197 f(methodDataKlassObj()); 198 f(klassKlassObj()); 199 f(arrayKlassKlassObj()); 200 f(objArrayKlassKlassObj()); 201 f(typeArrayKlassKlassObj()); 202 f(instanceKlassKlassObj()); 203 f(constantPoolKlassObj()); 204 f(systemObjArrayKlassObj()); 205 } 206 207 void Universe::oops_do(OopClosure* f, bool do_all) { 208 209 f->do_oop((oop*) &_int_mirror); 210 f->do_oop((oop*) &_float_mirror); 211 f->do_oop((oop*) &_double_mirror); 212 f->do_oop((oop*) &_byte_mirror); 213 f->do_oop((oop*) &_bool_mirror); 214 f->do_oop((oop*) &_char_mirror); 215 f->do_oop((oop*) &_long_mirror); 216 f->do_oop((oop*) &_short_mirror); 217 f->do_oop((oop*) &_void_mirror); 218 219 // It's important to iterate over these guys even if they are null, 220 // since that's how shared heaps are restored. 221 for (int i = T_BOOLEAN; i < T_VOID+1; i++) { 222 f->do_oop((oop*) &_mirrors[i]); 223 } 224 assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking"); 225 226 // %%% Consider moving those "shared oops" over here with the others. 227 f->do_oop((oop*)&_boolArrayKlassObj); 228 f->do_oop((oop*)&_byteArrayKlassObj); 229 f->do_oop((oop*)&_charArrayKlassObj); 230 f->do_oop((oop*)&_intArrayKlassObj); 231 f->do_oop((oop*)&_shortArrayKlassObj); 232 f->do_oop((oop*)&_longArrayKlassObj); 233 f->do_oop((oop*)&_singleArrayKlassObj); 234 f->do_oop((oop*)&_doubleArrayKlassObj); 235 f->do_oop((oop*)&_objectArrayKlassObj); 236 { 237 for (int i = 0; i < T_VOID+1; i++) { 238 if (_typeArrayKlassObjs[i] != NULL) { 239 assert(i >= T_BOOLEAN, "checking"); 240 f->do_oop((oop*)&_typeArrayKlassObjs[i]); 241 } else if (do_all) { 242 f->do_oop((oop*)&_typeArrayKlassObjs[i]); 243 } 244 } 245 } 246 f->do_oop((oop*)&_methodKlassObj); 247 f->do_oop((oop*)&_constMethodKlassObj); 248 f->do_oop((oop*)&_methodDataKlassObj); 249 f->do_oop((oop*)&_klassKlassObj); 250 f->do_oop((oop*)&_arrayKlassKlassObj); 251 f->do_oop((oop*)&_objArrayKlassKlassObj); 252 f->do_oop((oop*)&_typeArrayKlassKlassObj); 253 f->do_oop((oop*)&_instanceKlassKlassObj); 254 f->do_oop((oop*)&_constantPoolKlassObj); 255 f->do_oop((oop*)&_constantPoolCacheKlassObj); 256 f->do_oop((oop*)&_compiledICHolderKlassObj); 257 f->do_oop((oop*)&_systemObjArrayKlassObj); 258 f->do_oop((oop*)&_the_empty_byte_array); 259 f->do_oop((oop*)&_the_empty_short_array); 260 f->do_oop((oop*)&_the_empty_int_array); 261 f->do_oop((oop*)&_the_empty_system_obj_array); 262 f->do_oop((oop*)&_the_empty_class_klass_array); 263 f->do_oop((oop*)&_the_array_interfaces_array); 264 f->do_oop((oop*)&_the_null_string); 265 f->do_oop((oop*)&_the_min_jint_string); 266 _finalizer_register_cache->oops_do(f); 267 _loader_addClass_cache->oops_do(f); 268 _reflect_invoke_cache->oops_do(f); 269 f->do_oop((oop*)&_out_of_memory_error_java_heap); 270 f->do_oop((oop*)&_out_of_memory_error_perm_gen); 271 f->do_oop((oop*)&_out_of_memory_error_array_size); 272 f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit); 273 if (_primordial_loader_cache != (oop)NULL && _primordial_loader_cache != (oop)-1) { 274 f->do_oop((oop*)&_primordial_loader_cache); 275 } 276 if (_preallocated_out_of_memory_error_array != (oop)NULL) { // NULL when DumpSharedSpaces 277 f->do_oop((oop*)&_preallocated_out_of_memory_error_array); 278 } 279 f->do_oop((oop*)&_null_ptr_exception_instance); 280 f->do_oop((oop*)&_arithmetic_exception_instance); 281 f->do_oop((oop*)&_virtual_machine_error_instance); 282 f->do_oop((oop*)&_main_thread_group); 283 f->do_oop((oop*)&_system_thread_group); 284 f->do_oop((oop*)&_vm_exception); 285 debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);) 286 } 287 288 289 void Universe::check_alignment(uintx size, uintx alignment, const char* name) { 290 if (size < alignment || size % alignment != 0) { 291 ResourceMark rm; 292 stringStream st; 293 st.print("Size of %s (%ld bytes) must be aligned to %ld bytes", name, size, alignment); 294 char* error = st.as_string(); 295 vm_exit_during_initialization(error); 296 } 297 } 298 299 300 void Universe::genesis(TRAPS) { 301 ResourceMark rm; 302 { FlagSetting fs(_bootstrapping, true); 303 304 { MutexLocker mc(Compile_lock); 305 306 // determine base vtable size; without that we cannot create the array klasses 307 compute_base_vtable_size(); 308 309 if (!UseSharedSpaces) { 310 _klassKlassObj = klassKlass::create_klass(CHECK); 311 _arrayKlassKlassObj = arrayKlassKlass::create_klass(CHECK); 312 313 _objArrayKlassKlassObj = objArrayKlassKlass::create_klass(CHECK); 314 _instanceKlassKlassObj = instanceKlassKlass::create_klass(CHECK); 315 _typeArrayKlassKlassObj = typeArrayKlassKlass::create_klass(CHECK); 316 317 _boolArrayKlassObj = typeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK); 318 _charArrayKlassObj = typeArrayKlass::create_klass(T_CHAR, sizeof(jchar), CHECK); 319 _singleArrayKlassObj = typeArrayKlass::create_klass(T_FLOAT, sizeof(jfloat), CHECK); 320 _doubleArrayKlassObj = typeArrayKlass::create_klass(T_DOUBLE, sizeof(jdouble), CHECK); 321 _byteArrayKlassObj = typeArrayKlass::create_klass(T_BYTE, sizeof(jbyte), CHECK); 322 _shortArrayKlassObj = typeArrayKlass::create_klass(T_SHORT, sizeof(jshort), CHECK); 323 _intArrayKlassObj = typeArrayKlass::create_klass(T_INT, sizeof(jint), CHECK); 324 _longArrayKlassObj = typeArrayKlass::create_klass(T_LONG, sizeof(jlong), CHECK); 325 326 _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj; 327 _typeArrayKlassObjs[T_CHAR] = _charArrayKlassObj; 328 _typeArrayKlassObjs[T_FLOAT] = _singleArrayKlassObj; 329 _typeArrayKlassObjs[T_DOUBLE] = _doubleArrayKlassObj; 330 _typeArrayKlassObjs[T_BYTE] = _byteArrayKlassObj; 331 _typeArrayKlassObjs[T_SHORT] = _shortArrayKlassObj; 332 _typeArrayKlassObjs[T_INT] = _intArrayKlassObj; 333 _typeArrayKlassObjs[T_LONG] = _longArrayKlassObj; 334 335 _methodKlassObj = methodKlass::create_klass(CHECK); 336 _constMethodKlassObj = constMethodKlass::create_klass(CHECK); 337 _methodDataKlassObj = methodDataKlass::create_klass(CHECK); 338 _constantPoolKlassObj = constantPoolKlass::create_klass(CHECK); 339 _constantPoolCacheKlassObj = constantPoolCacheKlass::create_klass(CHECK); 340 341 _compiledICHolderKlassObj = compiledICHolderKlass::create_klass(CHECK); 342 _systemObjArrayKlassObj = objArrayKlassKlass::cast(objArrayKlassKlassObj())->allocate_system_objArray_klass(CHECK); 343 344 _the_empty_byte_array = oopFactory::new_permanent_byteArray(0, CHECK); 345 _the_empty_short_array = oopFactory::new_permanent_shortArray(0, CHECK); 346 _the_empty_int_array = oopFactory::new_permanent_intArray(0, CHECK); 347 _the_empty_system_obj_array = oopFactory::new_system_objArray(0, CHECK); 348 349 _the_array_interfaces_array = oopFactory::new_system_objArray(2, CHECK); 350 } 351 } 352 353 vmSymbols::initialize(CHECK); 354 355 SystemDictionary::initialize(CHECK); 356 357 klassOop ok = SystemDictionary::Object_klass(); 358 359 _the_null_string = StringTable::intern("null", CHECK); 360 _the_min_jint_string = StringTable::intern("-2147483648", CHECK); 361 362 if (UseSharedSpaces) { 363 // Verify shared interfaces array. 364 assert(_the_array_interfaces_array->obj_at(0) == 365 SystemDictionary::Cloneable_klass(), "u3"); 366 assert(_the_array_interfaces_array->obj_at(1) == 367 SystemDictionary::Serializable_klass(), "u3"); 368 369 // Verify element klass for system obj array klass 370 assert(objArrayKlass::cast(_systemObjArrayKlassObj)->element_klass() == ok, "u1"); 371 assert(objArrayKlass::cast(_systemObjArrayKlassObj)->bottom_klass() == ok, "u2"); 372 373 // Verify super class for the classes created above 374 assert(Klass::cast(boolArrayKlassObj() )->super() == ok, "u3"); 375 assert(Klass::cast(charArrayKlassObj() )->super() == ok, "u3"); 376 assert(Klass::cast(singleArrayKlassObj() )->super() == ok, "u3"); 377 assert(Klass::cast(doubleArrayKlassObj() )->super() == ok, "u3"); 378 assert(Klass::cast(byteArrayKlassObj() )->super() == ok, "u3"); 379 assert(Klass::cast(shortArrayKlassObj() )->super() == ok, "u3"); 380 assert(Klass::cast(intArrayKlassObj() )->super() == ok, "u3"); 381 assert(Klass::cast(longArrayKlassObj() )->super() == ok, "u3"); 382 assert(Klass::cast(constantPoolKlassObj() )->super() == ok, "u3"); 383 assert(Klass::cast(systemObjArrayKlassObj())->super() == ok, "u3"); 384 } else { 385 // Set up shared interfaces array. (Do this before supers are set up.) 386 _the_array_interfaces_array->obj_at_put(0, SystemDictionary::Cloneable_klass()); 387 _the_array_interfaces_array->obj_at_put(1, SystemDictionary::Serializable_klass()); 388 389 // Set element klass for system obj array klass 390 objArrayKlass::cast(_systemObjArrayKlassObj)->set_element_klass(ok); 391 objArrayKlass::cast(_systemObjArrayKlassObj)->set_bottom_klass(ok); 392 393 // Set super class for the classes created above 394 Klass::cast(boolArrayKlassObj() )->initialize_supers(ok, CHECK); 395 Klass::cast(charArrayKlassObj() )->initialize_supers(ok, CHECK); 396 Klass::cast(singleArrayKlassObj() )->initialize_supers(ok, CHECK); 397 Klass::cast(doubleArrayKlassObj() )->initialize_supers(ok, CHECK); 398 Klass::cast(byteArrayKlassObj() )->initialize_supers(ok, CHECK); 399 Klass::cast(shortArrayKlassObj() )->initialize_supers(ok, CHECK); 400 Klass::cast(intArrayKlassObj() )->initialize_supers(ok, CHECK); 401 Klass::cast(longArrayKlassObj() )->initialize_supers(ok, CHECK); 402 Klass::cast(constantPoolKlassObj() )->initialize_supers(ok, CHECK); 403 Klass::cast(systemObjArrayKlassObj())->initialize_supers(ok, CHECK); 404 Klass::cast(boolArrayKlassObj() )->set_super(ok); 405 Klass::cast(charArrayKlassObj() )->set_super(ok); 406 Klass::cast(singleArrayKlassObj() )->set_super(ok); 407 Klass::cast(doubleArrayKlassObj() )->set_super(ok); 408 Klass::cast(byteArrayKlassObj() )->set_super(ok); 409 Klass::cast(shortArrayKlassObj() )->set_super(ok); 410 Klass::cast(intArrayKlassObj() )->set_super(ok); 411 Klass::cast(longArrayKlassObj() )->set_super(ok); 412 Klass::cast(constantPoolKlassObj() )->set_super(ok); 413 Klass::cast(systemObjArrayKlassObj())->set_super(ok); 414 } 415 416 Klass::cast(boolArrayKlassObj() )->append_to_sibling_list(); 417 Klass::cast(charArrayKlassObj() )->append_to_sibling_list(); 418 Klass::cast(singleArrayKlassObj() )->append_to_sibling_list(); 419 Klass::cast(doubleArrayKlassObj() )->append_to_sibling_list(); 420 Klass::cast(byteArrayKlassObj() )->append_to_sibling_list(); 421 Klass::cast(shortArrayKlassObj() )->append_to_sibling_list(); 422 Klass::cast(intArrayKlassObj() )->append_to_sibling_list(); 423 Klass::cast(longArrayKlassObj() )->append_to_sibling_list(); 424 Klass::cast(constantPoolKlassObj() )->append_to_sibling_list(); 425 Klass::cast(systemObjArrayKlassObj())->append_to_sibling_list(); 426 } // end of core bootstrapping 427 428 // Initialize _objectArrayKlass after core bootstraping to make 429 // sure the super class is set up properly for _objectArrayKlass. 430 _objectArrayKlassObj = instanceKlass:: 431 cast(SystemDictionary::Object_klass())->array_klass(1, CHECK); 432 // Add the class to the class hierarchy manually to make sure that 433 // its vtable is initialized after core bootstrapping is completed. 434 Klass::cast(_objectArrayKlassObj)->append_to_sibling_list(); 435 436 // Compute is_jdk version flags. 437 // Only 1.3 or later has the java.lang.Shutdown class. 438 // Only 1.4 or later has the java.lang.CharSequence interface. 439 // Only 1.5 or later has the java.lang.management.MemoryUsage class. 440 if (JDK_Version::is_partially_initialized()) { 441 uint8_t jdk_version; 442 klassOop k = SystemDictionary::resolve_or_null( 443 vmSymbols::java_lang_management_MemoryUsage(), THREAD); 444 CLEAR_PENDING_EXCEPTION; // ignore exceptions 445 if (k == NULL) { 446 k = SystemDictionary::resolve_or_null( 447 vmSymbols::java_lang_CharSequence(), THREAD); 448 CLEAR_PENDING_EXCEPTION; // ignore exceptions 449 if (k == NULL) { 450 k = SystemDictionary::resolve_or_null( 451 vmSymbols::java_lang_Shutdown(), THREAD); 452 CLEAR_PENDING_EXCEPTION; // ignore exceptions 453 if (k == NULL) { 454 jdk_version = 2; 455 } else { 456 jdk_version = 3; 457 } 458 } else { 459 jdk_version = 4; 460 } 461 } else { 462 jdk_version = 5; 463 } 464 JDK_Version::fully_initialize(jdk_version); 465 } 466 467 #ifdef ASSERT 468 if (FullGCALot) { 469 // Allocate an array of dummy objects. 470 // We'd like these to be at the bottom of the old generation, 471 // so that when we free one and then collect, 472 // (almost) the whole heap moves 473 // and we find out if we actually update all the oops correctly. 474 // But we can't allocate directly in the old generation, 475 // so we allocate wherever, and hope that the first collection 476 // moves these objects to the bottom of the old generation. 477 // We can allocate directly in the permanent generation, so we do. 478 int size; 479 if (UseConcMarkSweepGC) { 480 warning("Using +FullGCALot with concurrent mark sweep gc " 481 "will not force all objects to relocate"); 482 size = FullGCALotDummies; 483 } else { 484 size = FullGCALotDummies * 2; 485 } 486 objArrayOop naked_array = oopFactory::new_system_objArray(size, CHECK); 487 objArrayHandle dummy_array(THREAD, naked_array); 488 int i = 0; 489 while (i < size) { 490 if (!UseConcMarkSweepGC) { 491 // Allocate dummy in old generation 492 oop dummy = instanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK); 493 dummy_array->obj_at_put(i++, dummy); 494 } 495 // Allocate dummy in permanent generation 496 oop dummy = instanceKlass::cast(SystemDictionary::Object_klass())->allocate_permanent_instance(CHECK); 497 dummy_array->obj_at_put(i++, dummy); 498 } 499 { 500 // Only modify the global variable inside the mutex. 501 // If we had a race to here, the other dummy_array instances 502 // and their elements just get dropped on the floor, which is fine. 503 MutexLocker ml(FullGCALot_lock); 504 if (_fullgc_alot_dummy_array == NULL) { 505 _fullgc_alot_dummy_array = dummy_array(); 506 } 507 } 508 assert(i == _fullgc_alot_dummy_array->length(), "just checking"); 509 } 510 #endif 511 } 512 513 514 static inline void* dereference(void* addr) { 515 return *(void**)addr; 516 } 517 518 static inline void add_vtable(void** list, int* n, void* o, int count) { 519 guarantee((*n) < count, "vtable list too small"); 520 void* vtable = dereference(o); 521 assert(dereference(vtable) != NULL, "invalid vtable"); 522 list[(*n)++] = vtable; 523 } 524 525 void Universe::init_self_patching_vtbl_list(void** list, int count) { 526 int n = 0; 527 { klassKlass o; add_vtable(list, &n, &o, count); } 528 { arrayKlassKlass o; add_vtable(list, &n, &o, count); } 529 { objArrayKlassKlass o; add_vtable(list, &n, &o, count); } 530 { instanceKlassKlass o; add_vtable(list, &n, &o, count); } 531 { instanceKlass o; add_vtable(list, &n, &o, count); } 532 { instanceMirrorKlass o; add_vtable(list, &n, &o, count); } 533 { instanceRefKlass o; add_vtable(list, &n, &o, count); } 534 { typeArrayKlassKlass o; add_vtable(list, &n, &o, count); } 535 { typeArrayKlass o; add_vtable(list, &n, &o, count); } 536 { methodKlass o; add_vtable(list, &n, &o, count); } 537 { constMethodKlass o; add_vtable(list, &n, &o, count); } 538 { constantPoolKlass o; add_vtable(list, &n, &o, count); } 539 { constantPoolCacheKlass o; add_vtable(list, &n, &o, count); } 540 { objArrayKlass o; add_vtable(list, &n, &o, count); } 541 { methodDataKlass o; add_vtable(list, &n, &o, count); } 542 { compiledICHolderKlass o; add_vtable(list, &n, &o, count); } 543 #ifndef PRODUCT 544 // In non-product builds CHeapObj is derived from AllocatedObj, 545 // so symbols in CDS archive should have their vtable pointer patched. 546 { Symbol o; add_vtable(list, &n, &o, count); } 547 #endif 548 } 549 550 551 class FixupMirrorClosure: public ObjectClosure { 552 public: 553 virtual void do_object(oop obj) { 554 if (obj->is_klass()) { 555 EXCEPTION_MARK; 556 KlassHandle k(THREAD, klassOop(obj)); 557 // We will never reach the CATCH below since Exceptions::_throw will cause 558 // the VM to exit if an exception is thrown during initialization 559 java_lang_Class::fixup_mirror(k, CATCH); 560 // This call unconditionally creates a new mirror for k, 561 // and links in k's component_mirror field if k is an array. 562 // If k is an objArray, k's element type must already have 563 // a mirror. In other words, this closure must process 564 // the component type of an objArray k before it processes k. 565 // This works because the permgen iterator presents arrays 566 // and their component types in order of creation. 567 } 568 } 569 }; 570 571 void Universe::initialize_basic_type_mirrors(TRAPS) { 572 if (UseSharedSpaces) { 573 assert(_int_mirror != NULL, "already loaded"); 574 assert(_void_mirror == _mirrors[T_VOID], "consistently loaded"); 575 } else { 576 577 assert(_int_mirror==NULL, "basic type mirrors already initialized"); 578 _int_mirror = 579 java_lang_Class::create_basic_type_mirror("int", T_INT, CHECK); 580 _float_mirror = 581 java_lang_Class::create_basic_type_mirror("float", T_FLOAT, CHECK); 582 _double_mirror = 583 java_lang_Class::create_basic_type_mirror("double", T_DOUBLE, CHECK); 584 _byte_mirror = 585 java_lang_Class::create_basic_type_mirror("byte", T_BYTE, CHECK); 586 _bool_mirror = 587 java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK); 588 _char_mirror = 589 java_lang_Class::create_basic_type_mirror("char", T_CHAR, CHECK); 590 _long_mirror = 591 java_lang_Class::create_basic_type_mirror("long", T_LONG, CHECK); 592 _short_mirror = 593 java_lang_Class::create_basic_type_mirror("short", T_SHORT, CHECK); 594 _void_mirror = 595 java_lang_Class::create_basic_type_mirror("void", T_VOID, CHECK); 596 597 _mirrors[T_INT] = _int_mirror; 598 _mirrors[T_FLOAT] = _float_mirror; 599 _mirrors[T_DOUBLE] = _double_mirror; 600 _mirrors[T_BYTE] = _byte_mirror; 601 _mirrors[T_BOOLEAN] = _bool_mirror; 602 _mirrors[T_CHAR] = _char_mirror; 603 _mirrors[T_LONG] = _long_mirror; 604 _mirrors[T_SHORT] = _short_mirror; 605 _mirrors[T_VOID] = _void_mirror; 606 //_mirrors[T_OBJECT] = instanceKlass::cast(_object_klass)->java_mirror(); 607 //_mirrors[T_ARRAY] = instanceKlass::cast(_object_klass)->java_mirror(); 608 } 609 } 610 611 void Universe::fixup_mirrors(TRAPS) { 612 // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly, 613 // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply 614 // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note 615 // that the number of objects allocated at this point is very small. 616 assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded"); 617 618 // Cache the start of the static fields 619 instanceMirrorKlass::init_offset_of_static_fields(); 620 621 FixupMirrorClosure blk; 622 Universe::heap()->permanent_object_iterate(&blk); 623 } 624 625 626 static bool has_run_finalizers_on_exit = false; 627 628 void Universe::run_finalizers_on_exit() { 629 if (has_run_finalizers_on_exit) return; 630 has_run_finalizers_on_exit = true; 631 632 // Called on VM exit. This ought to be run in a separate thread. 633 if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit"); 634 { 635 PRESERVE_EXCEPTION_MARK; 636 KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass()); 637 JavaValue result(T_VOID); 638 JavaCalls::call_static( 639 &result, 640 finalizer_klass, 641 vmSymbols::run_finalizers_on_exit_name(), 642 vmSymbols::void_method_signature(), 643 THREAD 644 ); 645 // Ignore any pending exceptions 646 CLEAR_PENDING_EXCEPTION; 647 } 648 } 649 650 651 // initialize_vtable could cause gc if 652 // 1) we specified true to initialize_vtable and 653 // 2) this ran after gc was enabled 654 // In case those ever change we use handles for oops 655 void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) { 656 // init vtable of k and all subclasses 657 Klass* ko = k_h()->klass_part(); 658 klassVtable* vt = ko->vtable(); 659 if (vt) vt->initialize_vtable(false, CHECK); 660 if (ko->oop_is_instance()) { 661 instanceKlass* ik = (instanceKlass*)ko; 662 for (KlassHandle s_h(THREAD, ik->subklass()); s_h() != NULL; s_h = (THREAD, s_h()->klass_part()->next_sibling())) { 663 reinitialize_vtable_of(s_h, CHECK); 664 } 665 } 666 } 667 668 669 void initialize_itable_for_klass(klassOop k, TRAPS) { 670 instanceKlass::cast(k)->itable()->initialize_itable(false, CHECK); 671 } 672 673 674 void Universe::reinitialize_itables(TRAPS) { 675 SystemDictionary::classes_do(initialize_itable_for_klass, CHECK); 676 677 } 678 679 680 bool Universe::on_page_boundary(void* addr) { 681 return ((uintptr_t) addr) % os::vm_page_size() == 0; 682 } 683 684 685 bool Universe::should_fill_in_stack_trace(Handle throwable) { 686 // never attempt to fill in the stack trace of preallocated errors that do not have 687 // backtrace. These errors are kept alive forever and may be "re-used" when all 688 // preallocated errors with backtrace have been consumed. Also need to avoid 689 // a potential loop which could happen if an out of memory occurs when attempting 690 // to allocate the backtrace. 691 return ((throwable() != Universe::_out_of_memory_error_java_heap) && 692 (throwable() != Universe::_out_of_memory_error_perm_gen) && 693 (throwable() != Universe::_out_of_memory_error_array_size) && 694 (throwable() != Universe::_out_of_memory_error_gc_overhead_limit)); 695 } 696 697 698 oop Universe::gen_out_of_memory_error(oop default_err) { 699 // generate an out of memory error: 700 // - if there is a preallocated error with backtrace available then return it wth 701 // a filled in stack trace. 702 // - if there are no preallocated errors with backtrace available then return 703 // an error without backtrace. 704 int next; 705 if (_preallocated_out_of_memory_error_avail_count > 0) { 706 next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count); 707 assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt"); 708 } else { 709 next = -1; 710 } 711 if (next < 0) { 712 // all preallocated errors have been used. 713 // return default 714 return default_err; 715 } else { 716 // get the error object at the slot and set set it to NULL so that the 717 // array isn't keeping it alive anymore. 718 oop exc = preallocated_out_of_memory_errors()->obj_at(next); 719 assert(exc != NULL, "slot has been used already"); 720 preallocated_out_of_memory_errors()->obj_at_put(next, NULL); 721 722 // use the message from the default error 723 oop msg = java_lang_Throwable::message(default_err); 724 assert(msg != NULL, "no message"); 725 java_lang_Throwable::set_message(exc, msg); 726 727 // populate the stack trace and return it. 728 java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc); 729 return exc; 730 } 731 } 732 733 static intptr_t non_oop_bits = 0; 734 735 void* Universe::non_oop_word() { 736 // Neither the high bits nor the low bits of this value is allowed 737 // to look like (respectively) the high or low bits of a real oop. 738 // 739 // High and low are CPU-specific notions, but low always includes 740 // the low-order bit. Since oops are always aligned at least mod 4, 741 // setting the low-order bit will ensure that the low half of the 742 // word will never look like that of a real oop. 743 // 744 // Using the OS-supplied non-memory-address word (usually 0 or -1) 745 // will take care of the high bits, however many there are. 746 747 if (non_oop_bits == 0) { 748 non_oop_bits = (intptr_t)os::non_memory_address_word() | 1; 749 } 750 751 return (void*)non_oop_bits; 752 } 753 754 jint universe_init() { 755 assert(!Universe::_fully_initialized, "called after initialize_vtables"); 756 guarantee(1 << LogHeapWordSize == sizeof(HeapWord), 757 "LogHeapWordSize is incorrect."); 758 guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?"); 759 guarantee(sizeof(oop) % sizeof(HeapWord) == 0, 760 "oop size is not not a multiple of HeapWord size"); 761 TraceTime timer("Genesis", TraceStartupTime); 762 GC_locker::lock(); // do not allow gc during bootstrapping 763 JavaClasses::compute_hard_coded_offsets(); 764 765 // Get map info from shared archive file. 766 if (DumpSharedSpaces) 767 UseSharedSpaces = false; 768 769 FileMapInfo* mapinfo = NULL; 770 if (UseSharedSpaces) { 771 mapinfo = NEW_C_HEAP_OBJ(FileMapInfo); 772 memset(mapinfo, 0, sizeof(FileMapInfo)); 773 774 // Open the shared archive file, read and validate the header. If 775 // initialization files, shared spaces [UseSharedSpaces] are 776 // disabled and the file is closed. 777 778 if (mapinfo->initialize()) { 779 FileMapInfo::set_current_info(mapinfo); 780 } else { 781 assert(!mapinfo->is_open() && !UseSharedSpaces, 782 "archive file not closed or shared spaces not disabled."); 783 } 784 } 785 786 jint status = Universe::initialize_heap(); 787 if (status != JNI_OK) { 788 return status; 789 } 790 791 // We have a heap so create the methodOop caches before 792 // CompactingPermGenGen::initialize_oops() tries to populate them. 793 Universe::_finalizer_register_cache = new LatestMethodOopCache(); 794 Universe::_loader_addClass_cache = new LatestMethodOopCache(); 795 Universe::_reflect_invoke_cache = new ActiveMethodOopsCache(); 796 797 if (UseSharedSpaces) { 798 799 // Read the data structures supporting the shared spaces (shared 800 // system dictionary, symbol table, etc.). After that, access to 801 // the file (other than the mapped regions) is no longer needed, and 802 // the file is closed. Closing the file does not affect the 803 // currently mapped regions. 804 805 CompactingPermGenGen::initialize_oops(); 806 mapinfo->close(); 807 808 } else { 809 SymbolTable::create_table(); 810 StringTable::create_table(); 811 ClassLoader::create_package_info_table(); 812 } 813 814 return JNI_OK; 815 } 816 817 // Choose the heap base address and oop encoding mode 818 // when compressed oops are used: 819 // Unscaled - Use 32-bits oops without encoding when 820 // NarrowOopHeapBaseMin + heap_size < 4Gb 821 // ZeroBased - Use zero based compressed oops with encoding when 822 // NarrowOopHeapBaseMin + heap_size < 32Gb 823 // HeapBased - Use compressed oops with heap base + encoding. 824 825 // 4Gb 826 static const uint64_t NarrowOopHeapMax = (uint64_t(max_juint) + 1); 827 // 32Gb 828 // OopEncodingHeapMax == NarrowOopHeapMax << LogMinObjAlignmentInBytes; 829 830 char* Universe::preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode) { 831 size_t base = 0; 832 #ifdef _LP64 833 if (UseCompressedOops) { 834 assert(mode == UnscaledNarrowOop || 835 mode == ZeroBasedNarrowOop || 836 mode == HeapBasedNarrowOop, "mode is invalid"); 837 const size_t total_size = heap_size + HeapBaseMinAddress; 838 // Return specified base for the first request. 839 if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) { 840 base = HeapBaseMinAddress; 841 } else if (total_size <= OopEncodingHeapMax && (mode != HeapBasedNarrowOop)) { 842 if (total_size <= NarrowOopHeapMax && (mode == UnscaledNarrowOop) && 843 (Universe::narrow_oop_shift() == 0)) { 844 // Use 32-bits oops without encoding and 845 // place heap's top on the 4Gb boundary 846 base = (NarrowOopHeapMax - heap_size); 847 } else { 848 // Can't reserve with NarrowOopShift == 0 849 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); 850 if (mode == UnscaledNarrowOop || 851 mode == ZeroBasedNarrowOop && total_size <= NarrowOopHeapMax) { 852 // Use zero based compressed oops with encoding and 853 // place heap's top on the 32Gb boundary in case 854 // total_size > 4Gb or failed to reserve below 4Gb. 855 base = (OopEncodingHeapMax - heap_size); 856 } 857 } 858 } else { 859 // Can't reserve below 32Gb. 860 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); 861 } 862 // Set narrow_oop_base and narrow_oop_use_implicit_null_checks 863 // used in ReservedHeapSpace() constructors. 864 // The final values will be set in initialize_heap() below. 865 if (base != 0 && (base + heap_size) <= OopEncodingHeapMax) { 866 // Use zero based compressed oops 867 Universe::set_narrow_oop_base(NULL); 868 // Don't need guard page for implicit checks in indexed 869 // addressing mode with zero based Compressed Oops. 870 Universe::set_narrow_oop_use_implicit_null_checks(true); 871 } else { 872 // Set to a non-NULL value so the ReservedSpace ctor computes 873 // the correct no-access prefix. 874 // The final value will be set in initialize_heap() below. 875 Universe::set_narrow_oop_base((address)NarrowOopHeapMax); 876 #ifdef _WIN64 877 if (UseLargePages) { 878 // Cannot allocate guard pages for implicit checks in indexed 879 // addressing mode when large pages are specified on windows. 880 Universe::set_narrow_oop_use_implicit_null_checks(false); 881 } 882 #endif // _WIN64 883 } 884 } 885 #endif 886 return (char*)base; // also return NULL (don't care) for 32-bit VM 887 } 888 889 jint Universe::initialize_heap() { 890 891 if (UseParallelGC) { 892 #ifndef SERIALGC 893 Universe::_collectedHeap = new ParallelScavengeHeap(); 894 #else // SERIALGC 895 fatal("UseParallelGC not supported in java kernel vm."); 896 #endif // SERIALGC 897 898 } else if (UseG1GC) { 899 #ifndef SERIALGC 900 G1CollectorPolicy* g1p = new G1CollectorPolicy(); 901 G1CollectedHeap* g1h = new G1CollectedHeap(g1p); 902 Universe::_collectedHeap = g1h; 903 #else // SERIALGC 904 fatal("UseG1GC not supported in java kernel vm."); 905 #endif // SERIALGC 906 907 } else { 908 GenCollectorPolicy *gc_policy; 909 910 if (UseSerialGC) { 911 gc_policy = new MarkSweepPolicy(); 912 } else if (UseConcMarkSweepGC) { 913 #ifndef SERIALGC 914 if (UseAdaptiveSizePolicy) { 915 gc_policy = new ASConcurrentMarkSweepPolicy(); 916 } else { 917 gc_policy = new ConcurrentMarkSweepPolicy(); 918 } 919 #else // SERIALGC 920 fatal("UseConcMarkSweepGC not supported in java kernel vm."); 921 #endif // SERIALGC 922 } else { // default old generation 923 gc_policy = new MarkSweepPolicy(); 924 } 925 926 Universe::_collectedHeap = new GenCollectedHeap(gc_policy); 927 } 928 929 jint status = Universe::heap()->initialize(); 930 if (status != JNI_OK) { 931 return status; 932 } 933 934 #ifdef _LP64 935 if (UseCompressedOops) { 936 // Subtract a page because something can get allocated at heap base. 937 // This also makes implicit null checking work, because the 938 // memory+1 page below heap_base needs to cause a signal. 939 // See needs_explicit_null_check. 940 // Only set the heap base for compressed oops because it indicates 941 // compressed oops for pstack code. 942 bool verbose = PrintCompressedOopsMode || (PrintMiscellaneous && Verbose); 943 if (verbose) { 944 tty->cr(); 945 tty->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB", 946 Universe::heap()->base(), Universe::heap()->reserved_region().byte_size()/M); 947 } 948 if ((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax) { 949 // Can't reserve heap below 32Gb. 950 Universe::set_narrow_oop_base(Universe::heap()->base() - os::vm_page_size()); 951 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); 952 if (verbose) { 953 tty->print(", Compressed Oops with base: "PTR_FORMAT, Universe::narrow_oop_base()); 954 } 955 } else { 956 Universe::set_narrow_oop_base(0); 957 if (verbose) { 958 tty->print(", zero based Compressed Oops"); 959 } 960 #ifdef _WIN64 961 if (!Universe::narrow_oop_use_implicit_null_checks()) { 962 // Don't need guard page for implicit checks in indexed addressing 963 // mode with zero based Compressed Oops. 964 Universe::set_narrow_oop_use_implicit_null_checks(true); 965 } 966 #endif // _WIN64 967 if((uint64_t)Universe::heap()->reserved_region().end() > NarrowOopHeapMax) { 968 // Can't reserve heap below 4Gb. 969 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); 970 } else { 971 Universe::set_narrow_oop_shift(0); 972 if (verbose) { 973 tty->print(", 32-bits Oops"); 974 } 975 } 976 } 977 if (verbose) { 978 tty->cr(); 979 tty->cr(); 980 } 981 } 982 assert(Universe::narrow_oop_base() == (Universe::heap()->base() - os::vm_page_size()) || 983 Universe::narrow_oop_base() == NULL, "invalid value"); 984 assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes || 985 Universe::narrow_oop_shift() == 0, "invalid value"); 986 #endif 987 988 // We will never reach the CATCH below since Exceptions::_throw will cause 989 // the VM to exit if an exception is thrown during initialization 990 991 if (UseTLAB) { 992 assert(Universe::heap()->supports_tlab_allocation(), 993 "Should support thread-local allocation buffers"); 994 ThreadLocalAllocBuffer::startup_initialization(); 995 } 996 return JNI_OK; 997 } 998 999 // It's the caller's repsonsibility to ensure glitch-freedom 1000 // (if required). 1001 void Universe::update_heap_info_at_gc() { 1002 _heap_capacity_at_last_gc = heap()->capacity(); 1003 _heap_used_at_last_gc = heap()->used(); 1004 } 1005 1006 1007 1008 void universe2_init() { 1009 EXCEPTION_MARK; 1010 Universe::genesis(CATCH); 1011 // Although we'd like to verify here that the state of the heap 1012 // is good, we can't because the main thread has not yet added 1013 // itself to the threads list (so, using current interfaces 1014 // we can't "fill" its TLAB), unless TLABs are disabled. 1015 if (VerifyBeforeGC && !UseTLAB && 1016 Universe::heap()->total_collections() >= VerifyGCStartAt) { 1017 Universe::heap()->prepare_for_verify(); 1018 Universe::verify(); // make sure we're starting with a clean slate 1019 } 1020 } 1021 1022 1023 // This function is defined in JVM.cpp 1024 extern void initialize_converter_functions(); 1025 1026 bool universe_post_init() { 1027 assert(!is_init_completed(), "Error: initialization not yet completed!"); 1028 Universe::_fully_initialized = true; 1029 EXCEPTION_MARK; 1030 { ResourceMark rm; 1031 Interpreter::initialize(); // needed for interpreter entry points 1032 if (!UseSharedSpaces) { 1033 KlassHandle ok_h(THREAD, SystemDictionary::Object_klass()); 1034 Universe::reinitialize_vtable_of(ok_h, CHECK_false); 1035 Universe::reinitialize_itables(CHECK_false); 1036 } 1037 } 1038 1039 klassOop k; 1040 instanceKlassHandle k_h; 1041 if (!UseSharedSpaces) { 1042 // Setup preallocated empty java.lang.Class array 1043 Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false); 1044 // Setup preallocated OutOfMemoryError errors 1045 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false); 1046 k_h = instanceKlassHandle(THREAD, k); 1047 Universe::_out_of_memory_error_java_heap = k_h->allocate_permanent_instance(CHECK_false); 1048 Universe::_out_of_memory_error_perm_gen = k_h->allocate_permanent_instance(CHECK_false); 1049 Universe::_out_of_memory_error_array_size = k_h->allocate_permanent_instance(CHECK_false); 1050 Universe::_out_of_memory_error_gc_overhead_limit = 1051 k_h->allocate_permanent_instance(CHECK_false); 1052 1053 // Setup preallocated NullPointerException 1054 // (this is currently used for a cheap & dirty solution in compiler exception handling) 1055 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false); 1056 Universe::_null_ptr_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); 1057 // Setup preallocated ArithmeticException 1058 // (this is currently used for a cheap & dirty solution in compiler exception handling) 1059 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false); 1060 Universe::_arithmetic_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); 1061 // Virtual Machine Error for when we get into a situation we can't resolve 1062 k = SystemDictionary::resolve_or_fail( 1063 vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false); 1064 bool linked = instanceKlass::cast(k)->link_class_or_fail(CHECK_false); 1065 if (!linked) { 1066 tty->print_cr("Unable to link/verify VirtualMachineError class"); 1067 return false; // initialization failed 1068 } 1069 Universe::_virtual_machine_error_instance = 1070 instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); 1071 1072 Universe::_vm_exception = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); 1073 1074 } 1075 if (!DumpSharedSpaces) { 1076 // These are the only Java fields that are currently set during shared space dumping. 1077 // We prefer to not handle this generally, so we always reinitialize these detail messages. 1078 Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false); 1079 java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg()); 1080 1081 msg = java_lang_String::create_from_str("PermGen space", CHECK_false); 1082 java_lang_Throwable::set_message(Universe::_out_of_memory_error_perm_gen, msg()); 1083 1084 msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false); 1085 java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg()); 1086 1087 msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false); 1088 java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg()); 1089 1090 msg = java_lang_String::create_from_str("/ by zero", CHECK_false); 1091 java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg()); 1092 1093 // Setup the array of errors that have preallocated backtrace 1094 k = Universe::_out_of_memory_error_java_heap->klass(); 1095 assert(k->klass_part()->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error"); 1096 k_h = instanceKlassHandle(THREAD, k); 1097 1098 int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0; 1099 Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false); 1100 for (int i=0; i<len; i++) { 1101 oop err = k_h->allocate_permanent_instance(CHECK_false); 1102 Handle err_h = Handle(THREAD, err); 1103 java_lang_Throwable::allocate_backtrace(err_h, CHECK_false); 1104 Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h()); 1105 } 1106 Universe::_preallocated_out_of_memory_error_avail_count = (jint)len; 1107 } 1108 1109 1110 // Setup static method for registering finalizers 1111 // The finalizer klass must be linked before looking up the method, in 1112 // case it needs to get rewritten. 1113 instanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false); 1114 methodOop m = instanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method( 1115 vmSymbols::register_method_name(), 1116 vmSymbols::register_method_signature()); 1117 if (m == NULL || !m->is_static()) { 1118 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(), 1119 "java.lang.ref.Finalizer.register", false); 1120 } 1121 Universe::_finalizer_register_cache->init( 1122 SystemDictionary::Finalizer_klass(), m, CHECK_false); 1123 1124 // Resolve on first use and initialize class. 1125 // Note: No race-condition here, since a resolve will always return the same result 1126 1127 // Setup method for security checks 1128 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_reflect_Method(), true, CHECK_false); 1129 k_h = instanceKlassHandle(THREAD, k); 1130 k_h->link_class(CHECK_false); 1131 m = k_h->find_method(vmSymbols::invoke_name(), vmSymbols::object_object_array_object_signature()); 1132 if (m == NULL || m->is_static()) { 1133 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(), 1134 "java.lang.reflect.Method.invoke", false); 1135 } 1136 Universe::_reflect_invoke_cache->init(k_h(), m, CHECK_false); 1137 1138 // Setup method for registering loaded classes in class loader vector 1139 instanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false); 1140 m = instanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature()); 1141 if (m == NULL || m->is_static()) { 1142 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(), 1143 "java.lang.ClassLoader.addClass", false); 1144 } 1145 Universe::_loader_addClass_cache->init( 1146 SystemDictionary::ClassLoader_klass(), m, CHECK_false); 1147 1148 // The folowing is initializing converter functions for serialization in 1149 // JVM.cpp. If we clean up the StrictMath code above we may want to find 1150 // a better solution for this as well. 1151 initialize_converter_functions(); 1152 1153 // This needs to be done before the first scavenge/gc, since 1154 // it's an input to soft ref clearing policy. 1155 { 1156 MutexLocker x(Heap_lock); 1157 Universe::update_heap_info_at_gc(); 1158 } 1159 1160 // ("weak") refs processing infrastructure initialization 1161 Universe::heap()->post_initialize(); 1162 1163 GC_locker::unlock(); // allow gc after bootstrapping 1164 1165 MemoryService::set_universe_heap(Universe::_collectedHeap); 1166 return true; 1167 } 1168 1169 1170 void Universe::compute_base_vtable_size() { 1171 _base_vtable_size = ClassLoader::compute_Object_vtable(); 1172 } 1173 1174 1175 // %%% The Universe::flush_foo methods belong in CodeCache. 1176 1177 // Flushes compiled methods dependent on dependee. 1178 void Universe::flush_dependents_on(instanceKlassHandle dependee) { 1179 assert_lock_strong(Compile_lock); 1180 1181 if (CodeCache::number_of_nmethods_with_dependencies() == 0) return; 1182 1183 // CodeCache can only be updated by a thread_in_VM and they will all be 1184 // stopped dring the safepoint so CodeCache will be safe to update without 1185 // holding the CodeCache_lock. 1186 1187 KlassDepChange changes(dependee); 1188 1189 // Compute the dependent nmethods 1190 if (CodeCache::mark_for_deoptimization(changes) > 0) { 1191 // At least one nmethod has been marked for deoptimization 1192 VM_Deoptimize op; 1193 VMThread::execute(&op); 1194 } 1195 } 1196 1197 // Flushes compiled methods dependent on a particular CallSite 1198 // instance when its target is different than the given MethodHandle. 1199 void Universe::flush_dependents_on(Handle call_site, Handle method_handle) { 1200 assert_lock_strong(Compile_lock); 1201 1202 if (CodeCache::number_of_nmethods_with_dependencies() == 0) return; 1203 1204 // CodeCache can only be updated by a thread_in_VM and they will all be 1205 // stopped dring the safepoint so CodeCache will be safe to update without 1206 // holding the CodeCache_lock. 1207 1208 CallSiteDepChange changes(call_site(), method_handle()); 1209 1210 // Compute the dependent nmethods that have a reference to a 1211 // CallSite object. We use instanceKlass::mark_dependent_nmethod 1212 // directly instead of CodeCache::mark_for_deoptimization because we 1213 // want dependents on the call site class only not all classes in 1214 // the ContextStream. 1215 int marked = 0; 1216 { 1217 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1218 instanceKlass* call_site_klass = instanceKlass::cast(call_site->klass()); 1219 marked = call_site_klass->mark_dependent_nmethods(changes); 1220 } 1221 if (marked > 0) { 1222 // At least one nmethod has been marked for deoptimization 1223 VM_Deoptimize op; 1224 VMThread::execute(&op); 1225 } 1226 } 1227 1228 #ifdef HOTSWAP 1229 // Flushes compiled methods dependent on dependee in the evolutionary sense 1230 void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) { 1231 // --- Compile_lock is not held. However we are at a safepoint. 1232 assert_locked_or_safepoint(Compile_lock); 1233 if (CodeCache::number_of_nmethods_with_dependencies() == 0) return; 1234 1235 // CodeCache can only be updated by a thread_in_VM and they will all be 1236 // stopped dring the safepoint so CodeCache will be safe to update without 1237 // holding the CodeCache_lock. 1238 1239 // Compute the dependent nmethods 1240 if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) { 1241 // At least one nmethod has been marked for deoptimization 1242 1243 // All this already happens inside a VM_Operation, so we'll do all the work here. 1244 // Stuff copied from VM_Deoptimize and modified slightly. 1245 1246 // We do not want any GCs to happen while we are in the middle of this VM operation 1247 ResourceMark rm; 1248 DeoptimizationMarker dm; 1249 1250 // Deoptimize all activations depending on marked nmethods 1251 Deoptimization::deoptimize_dependents(); 1252 1253 // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies) 1254 CodeCache::make_marked_nmethods_not_entrant(); 1255 } 1256 } 1257 #endif // HOTSWAP 1258 1259 1260 // Flushes compiled methods dependent on dependee 1261 void Universe::flush_dependents_on_method(methodHandle m_h) { 1262 // --- Compile_lock is not held. However we are at a safepoint. 1263 assert_locked_or_safepoint(Compile_lock); 1264 1265 // CodeCache can only be updated by a thread_in_VM and they will all be 1266 // stopped dring the safepoint so CodeCache will be safe to update without 1267 // holding the CodeCache_lock. 1268 1269 // Compute the dependent nmethods 1270 if (CodeCache::mark_for_deoptimization(m_h()) > 0) { 1271 // At least one nmethod has been marked for deoptimization 1272 1273 // All this already happens inside a VM_Operation, so we'll do all the work here. 1274 // Stuff copied from VM_Deoptimize and modified slightly. 1275 1276 // We do not want any GCs to happen while we are in the middle of this VM operation 1277 ResourceMark rm; 1278 DeoptimizationMarker dm; 1279 1280 // Deoptimize all activations depending on marked nmethods 1281 Deoptimization::deoptimize_dependents(); 1282 1283 // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies) 1284 CodeCache::make_marked_nmethods_not_entrant(); 1285 } 1286 } 1287 1288 void Universe::print() { 1289 print_on(gclog_or_tty); 1290 } 1291 1292 void Universe::print_on(outputStream* st, bool extended) { 1293 st->print_cr("Heap"); 1294 if (!extended) { 1295 heap()->print_on(st); 1296 } else { 1297 heap()->print_extended_on(st); 1298 } 1299 } 1300 1301 void Universe::print_heap_at_SIGBREAK() { 1302 if (PrintHeapAtSIGBREAK) { 1303 MutexLocker hl(Heap_lock); 1304 print_on(tty); 1305 tty->cr(); 1306 tty->flush(); 1307 } 1308 } 1309 1310 void Universe::print_heap_before_gc(outputStream* st, bool ignore_extended) { 1311 st->print_cr("{Heap before GC invocations=%u (full %u):", 1312 heap()->total_collections(), 1313 heap()->total_full_collections()); 1314 if (!PrintHeapAtGCExtended || ignore_extended) { 1315 heap()->print_on(st); 1316 } else { 1317 heap()->print_extended_on(st); 1318 } 1319 } 1320 1321 void Universe::print_heap_after_gc(outputStream* st, bool ignore_extended) { 1322 st->print_cr("Heap after GC invocations=%u (full %u):", 1323 heap()->total_collections(), 1324 heap()->total_full_collections()); 1325 if (!PrintHeapAtGCExtended || ignore_extended) { 1326 heap()->print_on(st); 1327 } else { 1328 heap()->print_extended_on(st); 1329 } 1330 st->print_cr("}"); 1331 } 1332 1333 void Universe::verify(bool silent, VerifyOption option) { 1334 if (SharedSkipVerify) { 1335 return; 1336 } 1337 1338 // The use of _verify_in_progress is a temporary work around for 1339 // 6320749. Don't bother with a creating a class to set and clear 1340 // it since it is only used in this method and the control flow is 1341 // straight forward. 1342 _verify_in_progress = true; 1343 1344 COMPILER2_PRESENT( 1345 assert(!DerivedPointerTable::is_active(), 1346 "DPT should not be active during verification " 1347 "(of thread stacks below)"); 1348 ) 1349 1350 ResourceMark rm; 1351 HandleMark hm; // Handles created during verification can be zapped 1352 _verify_count++; 1353 1354 if (!silent) gclog_or_tty->print("[Verifying "); 1355 if (!silent) gclog_or_tty->print("threads "); 1356 Threads::verify(); 1357 heap()->verify(silent, option); 1358 1359 if (!silent) gclog_or_tty->print("syms "); 1360 SymbolTable::verify(); 1361 if (!silent) gclog_or_tty->print("strs "); 1362 StringTable::verify(); 1363 { 1364 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 1365 if (!silent) gclog_or_tty->print("zone "); 1366 CodeCache::verify(); 1367 } 1368 if (!silent) gclog_or_tty->print("dict "); 1369 SystemDictionary::verify(); 1370 if (!silent) gclog_or_tty->print("hand "); 1371 JNIHandles::verify(); 1372 if (!silent) gclog_or_tty->print("C-heap "); 1373 os::check_heap(); 1374 if (!silent) gclog_or_tty->print("code cache "); 1375 CodeCache::verify_oops(); 1376 if (!silent) gclog_or_tty->print_cr("]"); 1377 1378 _verify_in_progress = false; 1379 } 1380 1381 // Oop verification (see MacroAssembler::verify_oop) 1382 1383 static uintptr_t _verify_oop_data[2] = {0, (uintptr_t)-1}; 1384 static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1}; 1385 1386 1387 static void calculate_verify_data(uintptr_t verify_data[2], 1388 HeapWord* low_boundary, 1389 HeapWord* high_boundary) { 1390 assert(low_boundary < high_boundary, "bad interval"); 1391 1392 // decide which low-order bits we require to be clear: 1393 size_t alignSize = MinObjAlignmentInBytes; 1394 size_t min_object_size = CollectedHeap::min_fill_size(); 1395 1396 // make an inclusive limit: 1397 uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize; 1398 uintptr_t min = (uintptr_t)low_boundary; 1399 assert(min < max, "bad interval"); 1400 uintptr_t diff = max ^ min; 1401 1402 // throw away enough low-order bits to make the diff vanish 1403 uintptr_t mask = (uintptr_t)(-1); 1404 while ((mask & diff) != 0) 1405 mask <<= 1; 1406 uintptr_t bits = (min & mask); 1407 assert(bits == (max & mask), "correct mask"); 1408 // check an intermediate value between min and max, just to make sure: 1409 assert(bits == ((min + (max-min)/2) & mask), "correct mask"); 1410 1411 // require address alignment, too: 1412 mask |= (alignSize - 1); 1413 1414 if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) { 1415 assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability"); 1416 } 1417 verify_data[0] = mask; 1418 verify_data[1] = bits; 1419 } 1420 1421 1422 // Oop verification (see MacroAssembler::verify_oop) 1423 #ifndef PRODUCT 1424 1425 uintptr_t Universe::verify_oop_mask() { 1426 MemRegion m = heap()->reserved_region(); 1427 calculate_verify_data(_verify_oop_data, 1428 m.start(), 1429 m.end()); 1430 return _verify_oop_data[0]; 1431 } 1432 1433 1434 1435 uintptr_t Universe::verify_oop_bits() { 1436 verify_oop_mask(); 1437 return _verify_oop_data[1]; 1438 } 1439 1440 1441 uintptr_t Universe::verify_klass_mask() { 1442 /* $$$ 1443 // A klass can never live in the new space. Since the new and old 1444 // spaces can change size, we must settle for bounds-checking against 1445 // the bottom of the world, plus the smallest possible new and old 1446 // space sizes that may arise during execution. 1447 size_t min_new_size = Universe::new_size(); // in bytes 1448 size_t min_old_size = Universe::old_size(); // in bytes 1449 calculate_verify_data(_verify_klass_data, 1450 (HeapWord*)((uintptr_t)_new_gen->low_boundary + min_new_size + min_old_size), 1451 _perm_gen->high_boundary); 1452 */ 1453 // Why doesn't the above just say that klass's always live in the perm 1454 // gen? I'll see if that seems to work... 1455 MemRegion permanent_reserved; 1456 switch (Universe::heap()->kind()) { 1457 default: 1458 // ???: What if a CollectedHeap doesn't have a permanent generation? 1459 ShouldNotReachHere(); 1460 break; 1461 case CollectedHeap::GenCollectedHeap: 1462 case CollectedHeap::G1CollectedHeap: { 1463 SharedHeap* sh = (SharedHeap*) Universe::heap(); 1464 permanent_reserved = sh->perm_gen()->reserved(); 1465 break; 1466 } 1467 #ifndef SERIALGC 1468 case CollectedHeap::ParallelScavengeHeap: { 1469 ParallelScavengeHeap* psh = (ParallelScavengeHeap*) Universe::heap(); 1470 permanent_reserved = psh->perm_gen()->reserved(); 1471 break; 1472 } 1473 #endif // SERIALGC 1474 } 1475 calculate_verify_data(_verify_klass_data, 1476 permanent_reserved.start(), 1477 permanent_reserved.end()); 1478 1479 return _verify_klass_data[0]; 1480 } 1481 1482 1483 1484 uintptr_t Universe::verify_klass_bits() { 1485 verify_klass_mask(); 1486 return _verify_klass_data[1]; 1487 } 1488 1489 1490 uintptr_t Universe::verify_mark_mask() { 1491 return markOopDesc::lock_mask_in_place; 1492 } 1493 1494 1495 1496 uintptr_t Universe::verify_mark_bits() { 1497 intptr_t mask = verify_mark_mask(); 1498 intptr_t bits = (intptr_t)markOopDesc::prototype(); 1499 assert((bits & ~mask) == 0, "no stray header bits"); 1500 return bits; 1501 } 1502 #endif // PRODUCT 1503 1504 1505 void Universe::compute_verify_oop_data() { 1506 verify_oop_mask(); 1507 verify_oop_bits(); 1508 verify_mark_mask(); 1509 verify_mark_bits(); 1510 verify_klass_mask(); 1511 verify_klass_bits(); 1512 } 1513 1514 1515 void CommonMethodOopCache::init(klassOop k, methodOop m, TRAPS) { 1516 if (!UseSharedSpaces) { 1517 _klass = k; 1518 } 1519 #ifndef PRODUCT 1520 else { 1521 // sharing initilization should have already set up _klass 1522 assert(_klass != NULL, "just checking"); 1523 } 1524 #endif 1525 1526 _method_idnum = m->method_idnum(); 1527 assert(_method_idnum >= 0, "sanity check"); 1528 } 1529 1530 1531 ActiveMethodOopsCache::~ActiveMethodOopsCache() { 1532 if (_prev_methods != NULL) { 1533 for (int i = _prev_methods->length() - 1; i >= 0; i--) { 1534 jweak method_ref = _prev_methods->at(i); 1535 if (method_ref != NULL) { 1536 JNIHandles::destroy_weak_global(method_ref); 1537 } 1538 } 1539 delete _prev_methods; 1540 _prev_methods = NULL; 1541 } 1542 } 1543 1544 1545 void ActiveMethodOopsCache::add_previous_version(const methodOop method) { 1546 assert(Thread::current()->is_VM_thread(), 1547 "only VMThread can add previous versions"); 1548 1549 if (_prev_methods == NULL) { 1550 // This is the first previous version so make some space. 1551 // Start with 2 elements under the assumption that the class 1552 // won't be redefined much. 1553 _prev_methods = new (ResourceObj::C_HEAP) GrowableArray<jweak>(2, true); 1554 } 1555 1556 // RC_TRACE macro has an embedded ResourceMark 1557 RC_TRACE(0x00000100, 1558 ("add: %s(%s): adding prev version ref for cached method @%d", 1559 method->name()->as_C_string(), method->signature()->as_C_string(), 1560 _prev_methods->length())); 1561 1562 methodHandle method_h(method); 1563 jweak method_ref = JNIHandles::make_weak_global(method_h); 1564 _prev_methods->append(method_ref); 1565 1566 // Using weak references allows previous versions of the cached 1567 // method to be GC'ed when they are no longer needed. Since the 1568 // caller is the VMThread and we are at a safepoint, this is a good 1569 // time to clear out unused weak references. 1570 1571 for (int i = _prev_methods->length() - 1; i >= 0; i--) { 1572 jweak method_ref = _prev_methods->at(i); 1573 assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); 1574 if (method_ref == NULL) { 1575 _prev_methods->remove_at(i); 1576 // Since we are traversing the array backwards, we don't have to 1577 // do anything special with the index. 1578 continue; // robustness 1579 } 1580 1581 methodOop m = (methodOop)JNIHandles::resolve(method_ref); 1582 if (m == NULL) { 1583 // this method entry has been GC'ed so remove it 1584 JNIHandles::destroy_weak_global(method_ref); 1585 _prev_methods->remove_at(i); 1586 } else { 1587 // RC_TRACE macro has an embedded ResourceMark 1588 RC_TRACE(0x00000400, ("add: %s(%s): previous cached method @%d is alive", 1589 m->name()->as_C_string(), m->signature()->as_C_string(), i)); 1590 } 1591 } 1592 } // end add_previous_version() 1593 1594 1595 bool ActiveMethodOopsCache::is_same_method(const methodOop method) const { 1596 instanceKlass* ik = instanceKlass::cast(klass()); 1597 methodOop check_method = ik->method_with_idnum(method_idnum()); 1598 assert(check_method != NULL, "sanity check"); 1599 if (check_method == method) { 1600 // done with the easy case 1601 return true; 1602 } 1603 1604 if (_prev_methods != NULL) { 1605 // The cached method has been redefined at least once so search 1606 // the previous versions for a match. 1607 for (int i = 0; i < _prev_methods->length(); i++) { 1608 jweak method_ref = _prev_methods->at(i); 1609 assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); 1610 if (method_ref == NULL) { 1611 continue; // robustness 1612 } 1613 1614 check_method = (methodOop)JNIHandles::resolve(method_ref); 1615 if (check_method == method) { 1616 // a previous version matches 1617 return true; 1618 } 1619 } 1620 } 1621 1622 // either no previous versions or no previous version matched 1623 return false; 1624 } 1625 1626 1627 methodOop LatestMethodOopCache::get_methodOop() { 1628 instanceKlass* ik = instanceKlass::cast(klass()); 1629 methodOop m = ik->method_with_idnum(method_idnum()); 1630 assert(m != NULL, "sanity check"); 1631 return m; 1632 } 1633 1634 1635 #ifdef ASSERT 1636 // Release dummy object(s) at bottom of heap 1637 bool Universe::release_fullgc_alot_dummy() { 1638 MutexLocker ml(FullGCALot_lock); 1639 if (_fullgc_alot_dummy_array != NULL) { 1640 if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) { 1641 // No more dummies to release, release entire array instead 1642 _fullgc_alot_dummy_array = NULL; 1643 return false; 1644 } 1645 if (!UseConcMarkSweepGC) { 1646 // Release dummy at bottom of old generation 1647 _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL); 1648 } 1649 // Release dummy at bottom of permanent generation 1650 _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL); 1651 } 1652 return true; 1653 } 1654 1655 #endif // ASSERT