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* _pd_implies_cache;         // method for checking protection domain attributes
 141   static LatestMethodCache* _throw_illegal_access_error_cache; // Unsafe.throwIllegalAccessError() method
 142   static LatestMethodCache* _do_stack_walk_cache;      // method for stack walker callback
 143 
 144   // preallocated error objects (no backtrace)
 145   static oop          _out_of_memory_error_java_heap;
 146   static oop          _out_of_memory_error_metaspace;
 147   static oop          _out_of_memory_error_class_metaspace;
 148   static oop          _out_of_memory_error_array_size;
 149   static oop          _out_of_memory_error_gc_overhead_limit;
 150   static oop          _out_of_memory_error_realloc_objects;
 151   static oop          _out_of_memory_error_retry;
 152 
 153   // preallocated cause message for delayed StackOverflowError
 154   static oop          _delayed_stack_overflow_error_message;
 155 
 156   static Array<int>*            _the_empty_int_array;            // Canonicalized int array
 157   static Array<u2>*             _the_empty_short_array;          // Canonicalized short array
 158   static Array<Klass*>*         _the_empty_klass_array;          // Canonicalized klass array
 159   static Array<InstanceKlass*>* _the_empty_instance_klass_array; // Canonicalized instance klass array
 160   static Array<Method*>*        _the_empty_method_array;         // Canonicalized method array
 161 
 162   static Array<Klass*>*  _the_array_interfaces_array;
 163 
 164   // array of preallocated error objects with backtrace
 165   static objArrayOop   _preallocated_out_of_memory_error_array;
 166 
 167   // number of preallocated error objects available for use
 168   static volatile jint _preallocated_out_of_memory_error_avail_count;
 169 
 170   static oop          _null_ptr_exception_instance;   // preallocated exception object
 171   static oop          _arithmetic_exception_instance; // preallocated exception object
 172   static oop          _virtual_machine_error_instance; // preallocated exception object
 173   // The object used as an exception dummy when exceptions are thrown for
 174   // the vm thread.
 175   static oop          _vm_exception;
 176 
 177   // References waiting to be transferred to the ReferenceHandler
 178   static oop          _reference_pending_list;
 179 
 180   // The particular choice of collected heap.
 181   static CollectedHeap* _collectedHeap;
 182 
 183   static intptr_t _non_oop_bits;
 184 
 185   // For UseCompressedOops.
 186   static struct NarrowPtrStruct _narrow_oop;
 187   // For UseCompressedClassPointers.
 188   static struct NarrowPtrStruct _narrow_klass;
 189   static address _narrow_ptrs_base;
 190   // CompressedClassSpaceSize set to 1GB, but appear 3GB away from _narrow_ptrs_base during CDS dump.
 191   static uint64_t _narrow_klass_range;
 192   // array of dummy objects used with +FullGCAlot
 193   debug_only(static objArrayOop _fullgc_alot_dummy_array;)
 194   // index of next entry to clear
 195   debug_only(static int         _fullgc_alot_dummy_next;)
 196 
 197   // Compiler/dispatch support
 198   static int  _base_vtable_size;                      // Java vtbl size of klass Object (in words)
 199 
 200   // Initialization
 201   static bool _bootstrapping;                         // true during genesis
 202   static bool _module_initialized;                    // true after call_initPhase2 called
 203   static bool _fully_initialized;                     // true after universe_init and initialize_vtables called
 204 
 205   // the array of preallocated errors with backtraces
 206   static objArrayOop  preallocated_out_of_memory_errors()     { return _preallocated_out_of_memory_error_array; }
 207 
 208   // generate an out of memory error; if possible using an error with preallocated backtrace;
 209   // otherwise return the given default error.
 210   static oop        gen_out_of_memory_error(oop default_err);
 211 
 212   // Historic gc information
 213   static size_t _heap_capacity_at_last_gc;
 214   static size_t _heap_used_at_last_gc;
 215 
 216   static CollectedHeap* create_heap();
 217   static jint initialize_heap();
 218   static void initialize_basic_type_mirrors(TRAPS);
 219   static void fixup_mirrors(TRAPS);
 220 
 221   static void reinitialize_vtable_of(Klass* k, TRAPS);
 222   static void reinitialize_itables(TRAPS);
 223   static void compute_base_vtable_size();             // compute vtable size of class Object
 224 
 225   static void genesis(TRAPS);                         // Create the initial world
 226 
 227   // Mirrors for primitive classes (created eagerly)
 228   static oop check_mirror(oop m) {
 229     assert(m != NULL, "mirror not initialized");
 230     return m;
 231   }
 232 
 233   static void     set_narrow_oop_base(address base) {
 234     assert(UseCompressedOops, "no compressed oops?");
 235     _narrow_oop._base    = base;
 236   }
 237   static void     set_narrow_klass_base(address base) {
 238     assert(UseCompressedClassPointers, "no compressed klass ptrs?");
 239     _narrow_klass._base   = base;
 240   }
 241   static void     set_narrow_klass_range(uint64_t range) {
 242      assert(UseCompressedClassPointers, "no compressed klass ptrs?");
 243      _narrow_klass_range = range;
 244   }
 245   static void     set_narrow_oop_use_implicit_null_checks(bool use) {
 246     assert(UseCompressedOops, "no compressed ptrs?");
 247     _narrow_oop._use_implicit_null_checks   = use;
 248   }
 249 
 250   // Debugging
 251   static int _verify_count;                           // number of verifies done
 252 
 253   // True during call to verify().  Should only be set/cleared in verify().
 254   static bool _verify_in_progress;
 255   static long verify_flags;
 256 
 257   static uintptr_t _verify_oop_mask;
 258   static uintptr_t _verify_oop_bits;
 259 
 260   static void calculate_verify_data(HeapWord* low_boundary, HeapWord* high_boundary) PRODUCT_RETURN;
 261   static void compute_verify_oop_data();
 262 
 263  public:
 264   // Known classes in the VM
 265   static Klass* boolArrayKlassObj()                 { return typeArrayKlassObj(T_BOOLEAN); }
 266   static Klass* byteArrayKlassObj()                 { return typeArrayKlassObj(T_BYTE); }
 267   static Klass* charArrayKlassObj()                 { return typeArrayKlassObj(T_CHAR); }
 268   static Klass* intArrayKlassObj()                  { return typeArrayKlassObj(T_INT); }
 269   static Klass* shortArrayKlassObj()                { return typeArrayKlassObj(T_SHORT); }
 270   static Klass* longArrayKlassObj()                 { return typeArrayKlassObj(T_LONG); }
 271   static Klass* floatArrayKlassObj()                { return typeArrayKlassObj(T_FLOAT); }
 272   static Klass* doubleArrayKlassObj()               { return typeArrayKlassObj(T_DOUBLE); }
 273 
 274   static Klass* objectArrayKlassObj()               { return _objectArrayKlassObj; }
 275 
 276   static Klass* typeArrayKlassObj(BasicType t) {
 277     assert((uint)t >= T_BOOLEAN, "range check for type: %s", type2name(t));
 278     assert((uint)t < T_LONG+1,   "range check for type: %s", type2name(t));
 279     assert(_typeArrayKlassObjs[t] != NULL, "domain check");
 280     return _typeArrayKlassObjs[t];
 281   }
 282 
 283   // Known objects in the VM
 284   static oop int_mirror()                   { return check_mirror(_int_mirror); }
 285   static oop float_mirror()                 { return check_mirror(_float_mirror); }
 286   static oop double_mirror()                { return check_mirror(_double_mirror); }
 287   static oop byte_mirror()                  { return check_mirror(_byte_mirror); }
 288   static oop bool_mirror()                  { return check_mirror(_bool_mirror); }
 289   static oop char_mirror()                  { return check_mirror(_char_mirror); }
 290   static oop long_mirror()                  { return check_mirror(_long_mirror); }
 291   static oop short_mirror()                 { return check_mirror(_short_mirror); }
 292   static oop void_mirror()                  { return check_mirror(_void_mirror); }
 293 
 294   static void set_int_mirror(oop m)         { _int_mirror = m;    }
 295   static void set_float_mirror(oop m)       { _float_mirror = m;  }
 296   static void set_double_mirror(oop m)      { _double_mirror = m; }
 297   static void set_byte_mirror(oop m)        { _byte_mirror = m;   }
 298   static void set_bool_mirror(oop m)        { _bool_mirror = m;   }
 299   static void set_char_mirror(oop m)        { _char_mirror = m;   }
 300   static void set_long_mirror(oop m)        { _long_mirror = m;   }
 301   static void set_short_mirror(oop m)       { _short_mirror = m;  }
 302   static void set_void_mirror(oop m)        { _void_mirror = m;   }
 303 
 304   // table of same
 305   static oop _mirrors[T_VOID+1];
 306 
 307   static oop java_mirror(BasicType t) {
 308     assert((uint)t < T_VOID+1, "range check");
 309     return check_mirror(_mirrors[t]);
 310   }
 311   static oop      main_thread_group()                 { return _main_thread_group; }
 312   static void set_main_thread_group(oop group)        { _main_thread_group = group;}
 313 
 314   static oop      system_thread_group()               { return _system_thread_group; }
 315   static void set_system_thread_group(oop group)      { _system_thread_group = group;}
 316 
 317   static objArrayOop  the_empty_class_klass_array ()  { return _the_empty_class_klass_array;   }
 318   static Array<Klass*>* the_array_interfaces_array() { return _the_array_interfaces_array;   }
 319   static oop          the_null_string()               { return _the_null_string;               }
 320   static oop          the_min_jint_string()          { return _the_min_jint_string;          }
 321 
 322   static Method*      finalizer_register_method()     { return _finalizer_register_cache->get_method(); }
 323   static Method*      loader_addClass_method()        { return _loader_addClass_cache->get_method(); }
 324 
 325   static Method*      protection_domain_implies_method() { return _pd_implies_cache->get_method(); }
 326   static Method*      throw_illegal_access_error()    { return _throw_illegal_access_error_cache->get_method(); }
 327 
 328   static Method*      do_stack_walk_method()          { return _do_stack_walk_cache->get_method(); }
 329 
 330   static oop          the_null_sentinel()             { return _the_null_sentinel;             }
 331   static address      the_null_sentinel_addr()        { return (address) &_the_null_sentinel;  }
 332 
 333   // Function to initialize these
 334   static void initialize_known_methods(TRAPS);
 335 
 336   static oop          null_ptr_exception_instance()   { return _null_ptr_exception_instance;   }
 337   static oop          arithmetic_exception_instance() { return _arithmetic_exception_instance; }
 338   static oop          virtual_machine_error_instance() { return _virtual_machine_error_instance; }
 339   static oop          vm_exception()                  { return _vm_exception; }
 340 
 341   // Reference pending list manipulation.  Access is protected by
 342   // Heap_lock.  The getter, setter and predicate require the caller
 343   // owns the lock.  Swap is used by parallel non-concurrent reference
 344   // processing threads, where some higher level controller owns
 345   // Heap_lock, so requires the lock is locked, but not necessarily by
 346   // the current thread.
 347   static oop          reference_pending_list();
 348   static void         set_reference_pending_list(oop list);
 349   static bool         has_reference_pending_list();
 350   static oop          swap_reference_pending_list(oop list);
 351 
 352   static Array<int>*             the_empty_int_array()    { return _the_empty_int_array; }
 353   static Array<u2>*              the_empty_short_array()  { return _the_empty_short_array; }
 354   static Array<Method*>*         the_empty_method_array() { return _the_empty_method_array; }
 355   static Array<Klass*>*          the_empty_klass_array()  { return _the_empty_klass_array; }
 356   static Array<InstanceKlass*>*  the_empty_instance_klass_array() { return _the_empty_instance_klass_array; }
 357 
 358   // OutOfMemoryError support. Returns an error with the required message. The returned error
 359   // may or may not have a backtrace. If error has a backtrace then the stack trace is already
 360   // filled in.
 361   static oop out_of_memory_error_java_heap()          { return gen_out_of_memory_error(_out_of_memory_error_java_heap);  }
 362   static oop out_of_memory_error_metaspace()          { return gen_out_of_memory_error(_out_of_memory_error_metaspace);   }
 363   static oop out_of_memory_error_class_metaspace()    { return gen_out_of_memory_error(_out_of_memory_error_class_metaspace);   }
 364   static oop out_of_memory_error_array_size()         { return gen_out_of_memory_error(_out_of_memory_error_array_size); }
 365   static oop out_of_memory_error_gc_overhead_limit()  { return gen_out_of_memory_error(_out_of_memory_error_gc_overhead_limit);  }
 366   static oop out_of_memory_error_realloc_objects()    { return gen_out_of_memory_error(_out_of_memory_error_realloc_objects);  }
 367   // Throw default _out_of_memory_error_retry object as it will never propagate out of the VM
 368   static oop out_of_memory_error_retry()              { return _out_of_memory_error_retry;  }
 369   static oop delayed_stack_overflow_error_message()   { return _delayed_stack_overflow_error_message; }
 370 
 371   // The particular choice of collected heap.
 372   static CollectedHeap* heap() { return _collectedHeap; }
 373 
 374   // For UseCompressedOops
 375   // Narrow Oop encoding mode:
 376   // 0 - Use 32-bits oops without encoding when
 377   //     NarrowOopHeapBaseMin + heap_size < 4Gb
 378   // 1 - Use zero based compressed oops with encoding when
 379   //     NarrowOopHeapBaseMin + heap_size < 32Gb
 380   // 2 - Use compressed oops with disjoint heap base if
 381   //     base is 32G-aligned and base > 0. This allows certain
 382   //     optimizations in encoding/decoding.
 383   //     Disjoint: Bits used in base are disjoint from bits used
 384   //     for oops ==> oop = (cOop << 3) | base.  One can disjoint
 385   //     the bits of an oop into base and compressed oop.
 386   // 3 - Use compressed oops with heap base + encoding.
 387   enum NARROW_OOP_MODE {
 388     UnscaledNarrowOop  = 0,
 389     ZeroBasedNarrowOop = 1,
 390     DisjointBaseNarrowOop = 2,
 391     HeapBasedNarrowOop = 3,
 392     AnyNarrowOopMode = 4
 393   };
 394   static NARROW_OOP_MODE narrow_oop_mode();
 395   static const char* narrow_oop_mode_to_string(NARROW_OOP_MODE mode);
 396   static char*    preferred_heap_base(size_t heap_size, size_t alignment, NARROW_OOP_MODE mode);
 397   static char*    preferred_metaspace_base(size_t heap_size, NARROW_OOP_MODE mode);
 398   static address  narrow_oop_base()                  { return  _narrow_oop._base; }
 399   // Test whether bits of addr and possible offsets into the heap overlap.
 400   static bool     is_disjoint_heap_base_address(address addr) {
 401     return (((uint64_t)(intptr_t)addr) &
 402             (((uint64_t)UCONST64(0xFFFFffffFFFFffff)) >> (32-LogMinObjAlignmentInBytes))) == 0;
 403   }
 404   // Check for disjoint base compressed oops.
 405   static bool     narrow_oop_base_disjoint()        {
 406     return _narrow_oop._base != NULL && is_disjoint_heap_base_address(_narrow_oop._base);
 407   }
 408   // Check for real heapbased compressed oops.
 409   // We must subtract the base as the bits overlap.
 410   // If we negate above function, we also get unscaled and zerobased.
 411   static bool     narrow_oop_base_overlaps()          {
 412     return _narrow_oop._base != NULL && !is_disjoint_heap_base_address(_narrow_oop._base);
 413   }
 414   static bool  is_narrow_oop_base(void* addr)             { return (narrow_oop_base() == (address)addr); }
 415   static int      narrow_oop_shift()                      { return  _narrow_oop._shift; }
 416   static bool     narrow_oop_use_implicit_null_checks()   { return  _narrow_oop._use_implicit_null_checks; }
 417 
 418   // For UseCompressedClassPointers
 419   static address  narrow_klass_base()                     { return  _narrow_klass._base; }
 420   static bool  is_narrow_klass_base(void* addr)           { return (narrow_klass_base() == (address)addr); }
 421   static uint64_t narrow_klass_range()                    { return  _narrow_klass_range; }
 422   static int      narrow_klass_shift()                    { return  _narrow_klass._shift; }
 423   static bool     narrow_klass_use_implicit_null_checks() { return  _narrow_klass._use_implicit_null_checks; }
 424 
 425   static address* narrow_ptrs_base_addr()                 { return &_narrow_ptrs_base; }
 426   static void     set_narrow_ptrs_base(address a)         { _narrow_ptrs_base = a; }
 427   static address  narrow_ptrs_base()                      { return _narrow_ptrs_base; }
 428 
 429   static void     print_compressed_oops_mode(outputStream* st);
 430 
 431   // this is set in vm_version on sparc (and then reset in universe afaict)
 432   static void     set_narrow_oop_shift(int shift)         {
 433     _narrow_oop._shift   = shift;
 434   }
 435 
 436   static void     set_narrow_klass_shift(int shift)       {
 437     assert(shift == 0 || shift == LogKlassAlignmentInBytes, "invalid shift for klass ptrs");
 438     _narrow_klass._shift   = shift;
 439   }
 440 
 441   // Reserve Java heap and determine CompressedOops mode
 442   static ReservedSpace reserve_heap(size_t heap_size, size_t alignment);
 443 
 444   // Historic gc information
 445   static size_t get_heap_capacity_at_last_gc()         { return _heap_capacity_at_last_gc; }
 446   static size_t get_heap_free_at_last_gc()             { return _heap_capacity_at_last_gc - _heap_used_at_last_gc; }
 447   static size_t get_heap_used_at_last_gc()             { return _heap_used_at_last_gc; }
 448   static void update_heap_info_at_gc();
 449 
 450   // Testers
 451   static bool is_bootstrapping()                      { return _bootstrapping; }
 452   static bool is_module_initialized()                 { return _module_initialized; }
 453   static bool is_fully_initialized()                  { return _fully_initialized; }
 454 
 455   static bool        on_page_boundary(void* addr);
 456   static bool        should_fill_in_stack_trace(Handle throwable);
 457   static void check_alignment(uintx size, uintx alignment, const char* name);
 458 
 459   // Iteration
 460 
 461   // Apply "f" to the addresses of all the direct heap pointers maintained
 462   // as static fields of "Universe".
 463   static void oops_do(OopClosure* f);
 464 
 465   // CDS support
 466   static void serialize(SerializeClosure* f);
 467 
 468   // Apply "f" to all klasses for basic types (classes not present in
 469   // SystemDictionary).
 470   static void basic_type_classes_do(void f(Klass*));
 471   static void basic_type_classes_do(KlassClosure* closure);
 472   static void metaspace_pointers_do(MetaspaceClosure* it);
 473 
 474   // Debugging
 475   enum VERIFY_FLAGS {
 476     Verify_Threads = 1,
 477     Verify_Heap = 2,
 478     Verify_SymbolTable = 4,
 479     Verify_StringTable = 8,
 480     Verify_CodeCache = 16,
 481     Verify_SystemDictionary = 32,
 482     Verify_ClassLoaderDataGraph = 64,
 483     Verify_MetaspaceUtils = 128,
 484     Verify_JNIHandles = 256,
 485     Verify_CodeCacheOops = 512,
 486     Verify_All = -1
 487   };
 488   static void initialize_verify_flags();
 489   static bool should_verify_subset(uint subset);
 490   static bool verify_in_progress() { return _verify_in_progress; }
 491   static void verify(VerifyOption option, const char* prefix);
 492   static void verify(const char* prefix) {
 493     verify(VerifyOption_Default, prefix);
 494   }
 495   static void verify() {
 496     verify("");
 497   }
 498 
 499   static int  verify_count()       { return _verify_count; }
 500   static void print_on(outputStream* st);
 501   static void print_heap_at_SIGBREAK();
 502   static void print_heap_before_gc();
 503   static void print_heap_after_gc();
 504 
 505   // Change the number of dummy objects kept reachable by the full gc dummy
 506   // array; this should trigger relocation in a sliding compaction collector.
 507   debug_only(static bool release_fullgc_alot_dummy();)
 508   // The non-oop pattern (see compiledIC.hpp, etc)
 509   static void*   non_oop_word();
 510 
 511   // Oop verification (see MacroAssembler::verify_oop)
 512   static uintptr_t verify_oop_mask()          PRODUCT_RETURN0;
 513   static uintptr_t verify_oop_bits()          PRODUCT_RETURN0;
 514   static uintptr_t verify_mark_bits()         PRODUCT_RETURN0;
 515   static uintptr_t verify_mark_mask()         PRODUCT_RETURN0;
 516 
 517   // Compiler support
 518   static int base_vtable_size()               { return _base_vtable_size; }
 519 };
 520 
 521 class DeferredObjAllocEvent : public CHeapObj<mtInternal> {
 522   private:
 523     oop    _oop;
 524     size_t _bytesize;
 525     jint   _arena_id;
 526 
 527   public:
 528     DeferredObjAllocEvent(const oop o, const size_t s, const jint id) {
 529       _oop      = o;
 530       _bytesize = s;
 531       _arena_id = id;
 532     }
 533 
 534     ~DeferredObjAllocEvent() {
 535     }
 536 
 537     jint   arena_id() { return _arena_id; }
 538     size_t bytesize() { return _bytesize; }
 539     oop    get_oop()  { return _oop; }
 540 };
 541 
 542 #endif // SHARE_VM_MEMORY_UNIVERSE_HPP
--- EOF ---