1 /* 2 * Copyright (c) 1997, 2018, 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 #ifndef SHARE_VM_MEMORY_UNIVERSE_HPP 26 #define SHARE_VM_MEMORY_UNIVERSE_HPP 27 28 #include "oops/array.hpp" 29 #include "runtime/handles.hpp" 30 #include "utilities/growableArray.hpp" 31 32 // Universe is a name space holding known system classes and objects in the VM. 33 // 34 // Loaded classes are accessible through the SystemDictionary. 35 // 36 // The object heap is allocated and accessed through Universe, and various allocation 37 // support is provided. Allocation by the interpreter and compiled code is done inline 38 // and bails out to Scavenge::invoke_and_allocate. 39 40 class CollectedHeap; 41 class DeferredObjAllocEvent; 42 43 44 // A helper class for caching a Method* when the user of the cache 45 // only cares about the latest version of the Method*. This cache safely 46 // interacts with the RedefineClasses API. 47 48 class LatestMethodCache : public CHeapObj<mtClass> { 49 // We save the Klass* and the idnum of Method* in order to get 50 // the current cached Method*. 51 private: 52 Klass* _klass; 53 int _method_idnum; 54 55 public: 56 LatestMethodCache() { _klass = NULL; _method_idnum = -1; } 57 ~LatestMethodCache() { _klass = NULL; _method_idnum = -1; } 58 59 void init(Klass* k, Method* m); 60 Klass* klass() const { return _klass; } 61 int method_idnum() const { return _method_idnum; } 62 63 Method* get_method(); 64 65 // CDS support. Replace the klass in this with the archive version 66 // could use this for Enhanced Class Redefinition also. 67 void serialize(SerializeClosure* f) { 68 f->do_ptr((void**)&_klass); 69 } 70 void metaspace_pointers_do(MetaspaceClosure* it); 71 }; 72 73 74 // For UseCompressedOops. 75 struct NarrowPtrStruct { 76 // Base address for oop-within-java-object materialization. 77 // NULL if using wide oops or zero based narrow oops. 78 address _base; 79 // Number of shift bits for encoding/decoding narrow ptrs. 80 // 0 if using wide ptrs or zero based unscaled narrow ptrs, 81 // LogMinObjAlignmentInBytes/LogKlassAlignmentInBytes otherwise. 82 int _shift; 83 // Generate code with implicit null checks for narrow ptrs. 84 bool _use_implicit_null_checks; 85 }; 86 87 enum VerifyOption { 88 VerifyOption_Default = 0, 89 90 // G1 91 VerifyOption_G1UsePrevMarking = VerifyOption_Default, 92 VerifyOption_G1UseNextMarking = VerifyOption_G1UsePrevMarking + 1, 93 VerifyOption_G1UseFullMarking = VerifyOption_G1UseNextMarking + 1 94 }; 95 96 class Universe: AllStatic { 97 // Ugh. Universe is much too friendly. 98 friend class MarkSweep; 99 friend class oopDesc; 100 friend class ClassLoader; 101 friend class SystemDictionary; 102 friend class ReservedHeapSpace; 103 friend class VMStructs; 104 friend class VM_PopulateDumpSharedSpace; 105 friend class Metaspace; 106 friend class MetaspaceShared; 107 108 friend jint universe_init(); 109 friend void universe2_init(); 110 friend bool universe_post_init(); 111 friend void universe_post_module_init(); 112 113 private: 114 // Known classes in the VM 115 static Klass* _typeArrayKlassObjs[T_LONG+1]; 116 static Klass* _objectArrayKlassObj; 117 118 // Known objects in the VM 119 120 // Primitive objects 121 static oop _int_mirror; 122 static oop _float_mirror; 123 static oop _double_mirror; 124 static oop _byte_mirror; 125 static oop _bool_mirror; 126 static oop _char_mirror; 127 static oop _long_mirror; 128 static oop _short_mirror; 129 static oop _void_mirror; 130 131 static oop _main_thread_group; // Reference to the main thread group object 132 static oop _system_thread_group; // Reference to the system thread group object 133 134 static objArrayOop _the_empty_class_klass_array; // Canonicalized obj array of type java.lang.Class 135 static oop _the_null_sentinel; // A unique object pointer unused except as a sentinel for null. 136 static oop _the_null_string; // A cache of "null" as a Java string 137 static oop _the_min_jint_string; // A cache of "-2147483648" as a Java string 138 static LatestMethodCache* _finalizer_register_cache; // static method for registering finalizable objects 139 static LatestMethodCache* _loader_addClass_cache; // method for registering loaded classes in class loader vector 140 static LatestMethodCache* _throw_illegal_access_error_cache; // Unsafe.throwIllegalAccessError() method 141 static LatestMethodCache* _do_stack_walk_cache; // method for stack walker callback 142 143 // preallocated error objects (no backtrace) 144 static oop _out_of_memory_error_java_heap; 145 static oop _out_of_memory_error_metaspace; 146 static oop _out_of_memory_error_class_metaspace; 147 static oop _out_of_memory_error_array_size; 148 static oop _out_of_memory_error_gc_overhead_limit; 149 static oop _out_of_memory_error_realloc_objects; 150 static oop _out_of_memory_error_retry; 151 152 // preallocated cause message for delayed StackOverflowError 153 static oop _delayed_stack_overflow_error_message; 154 155 static Array<int>* _the_empty_int_array; // Canonicalized int array 156 static Array<u2>* _the_empty_short_array; // Canonicalized short array 157 static Array<Klass*>* _the_empty_klass_array; // Canonicalized klass array 158 static Array<InstanceKlass*>* _the_empty_instance_klass_array; // Canonicalized instance klass array 159 static Array<Method*>* _the_empty_method_array; // Canonicalized method array 160 161 static Array<Klass*>* _the_array_interfaces_array; 162 163 // array of preallocated error objects with backtrace 164 static objArrayOop _preallocated_out_of_memory_error_array; 165 166 // number of preallocated error objects available for use 167 static volatile jint _preallocated_out_of_memory_error_avail_count; 168 169 static oop _null_ptr_exception_instance; // preallocated exception object 170 static oop _arithmetic_exception_instance; // preallocated exception object 171 static oop _virtual_machine_error_instance; // preallocated exception object 172 // The object used as an exception dummy when exceptions are thrown for 173 // the vm thread. 174 static oop _vm_exception; 175 176 // References waiting to be transferred to the ReferenceHandler 177 static oop _reference_pending_list; 178 179 // The particular choice of collected heap. 180 static CollectedHeap* _collectedHeap; 181 182 static intptr_t _non_oop_bits; 183 184 // For UseCompressedOops. 185 static struct NarrowPtrStruct _narrow_oop; 186 // For UseCompressedClassPointers. 187 static struct NarrowPtrStruct _narrow_klass; 188 static address _narrow_ptrs_base; 189 // CompressedClassSpaceSize set to 1GB, but appear 3GB away from _narrow_ptrs_base during CDS dump. 190 static uint64_t _narrow_klass_range; 191 // array of dummy objects used with +FullGCAlot 192 debug_only(static objArrayOop _fullgc_alot_dummy_array;) 193 // index of next entry to clear 194 debug_only(static int _fullgc_alot_dummy_next;) 195 196 // Compiler/dispatch support 197 static int _base_vtable_size; // Java vtbl size of klass Object (in words) 198 199 // Initialization 200 static bool _bootstrapping; // true during genesis 201 static bool _module_initialized; // true after call_initPhase2 called 202 static bool _fully_initialized; // true after universe_init and initialize_vtables called 203 204 // the array of preallocated errors with backtraces 205 static objArrayOop preallocated_out_of_memory_errors() { return _preallocated_out_of_memory_error_array; } 206 207 // generate an out of memory error; if possible using an error with preallocated backtrace; 208 // otherwise return the given default error. 209 static oop gen_out_of_memory_error(oop default_err); 210 211 // Historic gc information 212 static size_t _heap_capacity_at_last_gc; 213 static size_t _heap_used_at_last_gc; 214 215 static CollectedHeap* create_heap(); 216 static jint initialize_heap(); 217 static void initialize_basic_type_mirrors(TRAPS); 218 static void fixup_mirrors(TRAPS); 219 220 static void reinitialize_vtable_of(Klass* k, TRAPS); 221 static void reinitialize_itables(TRAPS); 222 static void compute_base_vtable_size(); // compute vtable size of class Object 223 224 static void genesis(TRAPS); // Create the initial world 225 226 // Mirrors for primitive classes (created eagerly) 227 static oop check_mirror(oop m) { 228 assert(m != NULL, "mirror not initialized"); 229 return m; 230 } 231 232 static void set_narrow_oop_base(address base) { 233 assert(UseCompressedOops, "no compressed oops?"); 234 _narrow_oop._base = base; 235 } 236 static void set_narrow_klass_base(address base) { 237 assert(UseCompressedClassPointers, "no compressed klass ptrs?"); 238 _narrow_klass._base = base; 239 } 240 static void set_narrow_klass_range(uint64_t range) { 241 assert(UseCompressedClassPointers, "no compressed klass ptrs?"); 242 _narrow_klass_range = range; 243 } 244 static void set_narrow_oop_use_implicit_null_checks(bool use) { 245 assert(UseCompressedOops, "no compressed ptrs?"); 246 _narrow_oop._use_implicit_null_checks = use; 247 } 248 249 // Debugging 250 static int _verify_count; // number of verifies done 251 252 // True during call to verify(). Should only be set/cleared in verify(). 253 static bool _verify_in_progress; 254 static long verify_flags; 255 256 static uintptr_t _verify_oop_mask; 257 static uintptr_t _verify_oop_bits; 258 259 static void calculate_verify_data(HeapWord* low_boundary, HeapWord* high_boundary) PRODUCT_RETURN; 260 static void compute_verify_oop_data(); 261 262 public: 263 // Known classes in the VM 264 static Klass* boolArrayKlassObj() { return typeArrayKlassObj(T_BOOLEAN); } 265 static Klass* byteArrayKlassObj() { return typeArrayKlassObj(T_BYTE); } 266 static Klass* charArrayKlassObj() { return typeArrayKlassObj(T_CHAR); } 267 static Klass* intArrayKlassObj() { return typeArrayKlassObj(T_INT); } 268 static Klass* shortArrayKlassObj() { return typeArrayKlassObj(T_SHORT); } 269 static Klass* longArrayKlassObj() { return typeArrayKlassObj(T_LONG); } 270 static Klass* floatArrayKlassObj() { return typeArrayKlassObj(T_FLOAT); } 271 static Klass* doubleArrayKlassObj() { return typeArrayKlassObj(T_DOUBLE); } 272 273 static Klass* objectArrayKlassObj() { return _objectArrayKlassObj; } 274 275 static Klass* typeArrayKlassObj(BasicType t) { 276 assert((uint)t >= T_BOOLEAN, "range check for type: %s", type2name(t)); 277 assert((uint)t < T_LONG+1, "range check for type: %s", type2name(t)); 278 assert(_typeArrayKlassObjs[t] != NULL, "domain check"); 279 return _typeArrayKlassObjs[t]; 280 } 281 282 // Known objects in the VM 283 static oop int_mirror() { return check_mirror(_int_mirror); } 284 static oop float_mirror() { return check_mirror(_float_mirror); } 285 static oop double_mirror() { return check_mirror(_double_mirror); } 286 static oop byte_mirror() { return check_mirror(_byte_mirror); } 287 static oop bool_mirror() { return check_mirror(_bool_mirror); } 288 static oop char_mirror() { return check_mirror(_char_mirror); } 289 static oop long_mirror() { return check_mirror(_long_mirror); } 290 static oop short_mirror() { return check_mirror(_short_mirror); } 291 static oop void_mirror() { return check_mirror(_void_mirror); } 292 293 static void set_int_mirror(oop m) { _int_mirror = m; } 294 static void set_float_mirror(oop m) { _float_mirror = m; } 295 static void set_double_mirror(oop m) { _double_mirror = m; } 296 static void set_byte_mirror(oop m) { _byte_mirror = m; } 297 static void set_bool_mirror(oop m) { _bool_mirror = m; } 298 static void set_char_mirror(oop m) { _char_mirror = m; } 299 static void set_long_mirror(oop m) { _long_mirror = m; } 300 static void set_short_mirror(oop m) { _short_mirror = m; } 301 static void set_void_mirror(oop m) { _void_mirror = m; } 302 303 // table of same 304 static oop _mirrors[T_VOID+1]; 305 306 static oop java_mirror(BasicType t) { 307 assert((uint)t < T_VOID+1, "range check"); 308 return check_mirror(_mirrors[t]); 309 } 310 static oop main_thread_group() { return _main_thread_group; } 311 static void set_main_thread_group(oop group) { _main_thread_group = group;} 312 313 static oop system_thread_group() { return _system_thread_group; } 314 static void set_system_thread_group(oop group) { _system_thread_group = group;} 315 316 static objArrayOop the_empty_class_klass_array () { return _the_empty_class_klass_array; } 317 static Array<Klass*>* the_array_interfaces_array() { return _the_array_interfaces_array; } 318 static oop the_null_string() { return _the_null_string; } 319 static oop the_min_jint_string() { return _the_min_jint_string; } 320 321 static Method* finalizer_register_method() { return _finalizer_register_cache->get_method(); } 322 static Method* loader_addClass_method() { return _loader_addClass_cache->get_method(); } 323 324 static Method* throw_illegal_access_error() { return _throw_illegal_access_error_cache->get_method(); } 325 326 static Method* do_stack_walk_method() { return _do_stack_walk_cache->get_method(); } 327 328 static oop the_null_sentinel() { return _the_null_sentinel; } 329 static address the_null_sentinel_addr() { return (address) &_the_null_sentinel; } 330 331 // Function to initialize these 332 static void initialize_known_methods(TRAPS); 333 334 static oop null_ptr_exception_instance() { return _null_ptr_exception_instance; } 335 static oop arithmetic_exception_instance() { return _arithmetic_exception_instance; } 336 static oop virtual_machine_error_instance() { return _virtual_machine_error_instance; } 337 static oop vm_exception() { return _vm_exception; } 338 339 // Reference pending list manipulation. Access is protected by 340 // Heap_lock. The getter, setter and predicate require the caller 341 // owns the lock. Swap is used by parallel non-concurrent reference 342 // processing threads, where some higher level controller owns 343 // Heap_lock, so requires the lock is locked, but not necessarily by 344 // the current thread. 345 static oop reference_pending_list(); 346 static void set_reference_pending_list(oop list); 347 static bool has_reference_pending_list(); 348 static oop swap_reference_pending_list(oop list); 349 350 static Array<int>* the_empty_int_array() { return _the_empty_int_array; } 351 static Array<u2>* the_empty_short_array() { return _the_empty_short_array; } 352 static Array<Method*>* the_empty_method_array() { return _the_empty_method_array; } 353 static Array<Klass*>* the_empty_klass_array() { return _the_empty_klass_array; } 354 static Array<InstanceKlass*>* the_empty_instance_klass_array() { return _the_empty_instance_klass_array; } 355 356 // OutOfMemoryError support. Returns an error with the required message. The returned error 357 // may or may not have a backtrace. If error has a backtrace then the stack trace is already 358 // filled in. 359 static oop out_of_memory_error_java_heap() { return gen_out_of_memory_error(_out_of_memory_error_java_heap); } 360 static oop out_of_memory_error_metaspace() { return gen_out_of_memory_error(_out_of_memory_error_metaspace); } 361 static oop out_of_memory_error_class_metaspace() { return gen_out_of_memory_error(_out_of_memory_error_class_metaspace); } 362 static oop out_of_memory_error_array_size() { return gen_out_of_memory_error(_out_of_memory_error_array_size); } 363 static oop out_of_memory_error_gc_overhead_limit() { return gen_out_of_memory_error(_out_of_memory_error_gc_overhead_limit); } 364 static oop out_of_memory_error_realloc_objects() { return gen_out_of_memory_error(_out_of_memory_error_realloc_objects); } 365 // Throw default _out_of_memory_error_retry object as it will never propagate out of the VM 366 static oop out_of_memory_error_retry() { return _out_of_memory_error_retry; } 367 static oop delayed_stack_overflow_error_message() { return _delayed_stack_overflow_error_message; } 368 369 // The particular choice of collected heap. 370 static CollectedHeap* heap() { return _collectedHeap; } 371 372 // For UseCompressedOops 373 // Narrow Oop encoding mode: 374 // 0 - Use 32-bits oops without encoding when 375 // NarrowOopHeapBaseMin + heap_size < 4Gb 376 // 1 - Use zero based compressed oops with encoding when 377 // NarrowOopHeapBaseMin + heap_size < 32Gb 378 // 2 - Use compressed oops with disjoint heap base if 379 // base is 32G-aligned and base > 0. This allows certain 380 // optimizations in encoding/decoding. 381 // Disjoint: Bits used in base are disjoint from bits used 382 // for oops ==> oop = (cOop << 3) | base. One can disjoint 383 // the bits of an oop into base and compressed oop. 384 // 3 - Use compressed oops with heap base + encoding. 385 enum NARROW_OOP_MODE { 386 UnscaledNarrowOop = 0, 387 ZeroBasedNarrowOop = 1, 388 DisjointBaseNarrowOop = 2, 389 HeapBasedNarrowOop = 3, 390 AnyNarrowOopMode = 4 391 }; 392 static NARROW_OOP_MODE narrow_oop_mode(); 393 static const char* narrow_oop_mode_to_string(NARROW_OOP_MODE mode); 394 static char* preferred_heap_base(size_t heap_size, size_t alignment, NARROW_OOP_MODE mode); 395 static char* preferred_metaspace_base(size_t heap_size, NARROW_OOP_MODE mode); 396 static address narrow_oop_base() { return _narrow_oop._base; } 397 // Test whether bits of addr and possible offsets into the heap overlap. 398 static bool is_disjoint_heap_base_address(address addr) { 399 return (((uint64_t)(intptr_t)addr) & 400 (((uint64_t)UCONST64(0xFFFFffffFFFFffff)) >> (32-LogMinObjAlignmentInBytes))) == 0; 401 } 402 // Check for disjoint base compressed oops. 403 static bool narrow_oop_base_disjoint() { 404 return _narrow_oop._base != NULL && is_disjoint_heap_base_address(_narrow_oop._base); 405 } 406 // Check for real heapbased compressed oops. 407 // We must subtract the base as the bits overlap. 408 // If we negate above function, we also get unscaled and zerobased. 409 static bool narrow_oop_base_overlaps() { 410 return _narrow_oop._base != NULL && !is_disjoint_heap_base_address(_narrow_oop._base); 411 } 412 static bool is_narrow_oop_base(void* addr) { return (narrow_oop_base() == (address)addr); } 413 static int narrow_oop_shift() { return _narrow_oop._shift; } 414 static bool narrow_oop_use_implicit_null_checks() { return _narrow_oop._use_implicit_null_checks; } 415 416 // For UseCompressedClassPointers 417 static address narrow_klass_base() { return _narrow_klass._base; } 418 static bool is_narrow_klass_base(void* addr) { return (narrow_klass_base() == (address)addr); } 419 static uint64_t narrow_klass_range() { return _narrow_klass_range; } 420 static int narrow_klass_shift() { return _narrow_klass._shift; } 421 static bool narrow_klass_use_implicit_null_checks() { return _narrow_klass._use_implicit_null_checks; } 422 423 static address* narrow_ptrs_base_addr() { return &_narrow_ptrs_base; } 424 static void set_narrow_ptrs_base(address a) { _narrow_ptrs_base = a; } 425 static address narrow_ptrs_base() { return _narrow_ptrs_base; } 426 427 static void print_compressed_oops_mode(outputStream* st); 428 429 // this is set in vm_version on sparc (and then reset in universe afaict) 430 static void set_narrow_oop_shift(int shift) { 431 _narrow_oop._shift = shift; 432 } 433 434 static void set_narrow_klass_shift(int shift) { 435 assert(shift == 0 || shift == LogKlassAlignmentInBytes, "invalid shift for klass ptrs"); 436 _narrow_klass._shift = shift; 437 } 438 439 // Reserve Java heap and determine CompressedOops mode 440 static ReservedSpace reserve_heap(size_t heap_size, size_t alignment); 441 442 // Historic gc information 443 static size_t get_heap_capacity_at_last_gc() { return _heap_capacity_at_last_gc; } 444 static size_t get_heap_free_at_last_gc() { return _heap_capacity_at_last_gc - _heap_used_at_last_gc; } 445 static size_t get_heap_used_at_last_gc() { return _heap_used_at_last_gc; } 446 static void update_heap_info_at_gc(); 447 448 // Testers 449 static bool is_bootstrapping() { return _bootstrapping; } 450 static bool is_module_initialized() { return _module_initialized; } 451 static bool is_fully_initialized() { return _fully_initialized; } 452 453 static bool on_page_boundary(void* addr); 454 static bool should_fill_in_stack_trace(Handle throwable); 455 static void check_alignment(uintx size, uintx alignment, const char* name); 456 457 // Iteration 458 459 // Apply "f" to the addresses of all the direct heap pointers maintained 460 // as static fields of "Universe". 461 static void oops_do(OopClosure* f); 462 463 // CDS support 464 static void serialize(SerializeClosure* f); 465 466 // Apply "f" to all klasses for basic types (classes not present in 467 // SystemDictionary). 468 static void basic_type_classes_do(void f(Klass*)); 469 static void basic_type_classes_do(KlassClosure* closure); 470 static void metaspace_pointers_do(MetaspaceClosure* it); 471 472 // Debugging 473 enum VERIFY_FLAGS { 474 Verify_Threads = 1, 475 Verify_Heap = 2, 476 Verify_SymbolTable = 4, 477 Verify_StringTable = 8, 478 Verify_CodeCache = 16, 479 Verify_SystemDictionary = 32, 480 Verify_ClassLoaderDataGraph = 64, 481 Verify_MetaspaceUtils = 128, 482 Verify_JNIHandles = 256, 483 Verify_CodeCacheOops = 512, 484 Verify_All = -1 485 }; 486 static void initialize_verify_flags(); 487 static bool should_verify_subset(uint subset); 488 static bool verify_in_progress() { return _verify_in_progress; } 489 static void verify(VerifyOption option, const char* prefix); 490 static void verify(const char* prefix) { 491 verify(VerifyOption_Default, prefix); 492 } 493 static void verify() { 494 verify(""); 495 } 496 497 static int verify_count() { return _verify_count; } 498 static void print_on(outputStream* st); 499 static void print_heap_at_SIGBREAK(); 500 static void print_heap_before_gc(); 501 static void print_heap_after_gc(); 502 503 // Change the number of dummy objects kept reachable by the full gc dummy 504 // array; this should trigger relocation in a sliding compaction collector. 505 debug_only(static bool release_fullgc_alot_dummy();) 506 // The non-oop pattern (see compiledIC.hpp, etc) 507 static void* non_oop_word(); 508 509 // Oop verification (see MacroAssembler::verify_oop) 510 static uintptr_t verify_oop_mask() PRODUCT_RETURN0; 511 static uintptr_t verify_oop_bits() PRODUCT_RETURN0; 512 static uintptr_t verify_mark_bits() PRODUCT_RETURN0; 513 static uintptr_t verify_mark_mask() PRODUCT_RETURN0; 514 515 // Compiler support 516 static int base_vtable_size() { return _base_vtable_size; } 517 }; 518 519 class DeferredObjAllocEvent : public CHeapObj<mtInternal> { 520 private: 521 oop _oop; 522 size_t _bytesize; 523 jint _arena_id; 524 525 public: 526 DeferredObjAllocEvent(const oop o, const size_t s, const jint id) { 527 _oop = o; 528 _bytesize = s; 529 _arena_id = id; 530 } 531 532 ~DeferredObjAllocEvent() { 533 } 534 535 jint arena_id() { return _arena_id; } 536 size_t bytesize() { return _bytesize; } 537 oop get_oop() { return _oop; } 538 }; 539 540 #endif // SHARE_VM_MEMORY_UNIVERSE_HPP