1 /*
   2  * Copyright (c) 1997, 2019, 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
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  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.
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  23  */
  24 
  25 #ifndef SHARE_OOPS_OOP_INLINE_HPP
  26 #define SHARE_OOPS_OOP_INLINE_HPP
  27 
  28 #include "gc/shared/collectedHeap.hpp"
  29 #include "memory/universe.hpp"
  30 #include "oops/access.inline.hpp"
  31 #include "oops/arrayKlass.hpp"
  32 #include "oops/arrayOop.hpp"
  33 #include "oops/compressedOops.inline.hpp"
  34 #include "oops/klass.inline.hpp"
  35 #include "oops/markOop.inline.hpp"
  36 #include "oops/oop.hpp"
  37 #include "runtime/atomic.hpp"
  38 #include "runtime/orderAccess.hpp"
  39 #include "runtime/os.hpp"
  40 #include "utilities/align.hpp"
  41 #include "utilities/macros.hpp"
  42 
  43 // Implementation of all inlined member functions defined in oop.hpp
  44 // We need a separate file to avoid circular references
  45 
  46 markOop  oopDesc::mark()      const {
  47   return HeapAccess<MO_VOLATILE>::load_at(as_oop(), mark_offset_in_bytes());
  48 }
  49 
  50 markOop  oopDesc::mark_raw()  const {
  51   return _mark;
  52 }
  53 
  54 markOop* oopDesc::mark_addr_raw() const {
  55   return (markOop*) &_mark;
  56 }
  57 
  58 void oopDesc::set_mark(volatile markOop m) {
  59   HeapAccess<MO_VOLATILE>::store_at(as_oop(), mark_offset_in_bytes(), m);
  60 }
  61 
  62 void oopDesc::set_mark_raw(volatile markOop m) {
  63   _mark = m;
  64 }
  65 
  66 void oopDesc::set_mark_raw(HeapWord* mem, markOop m) {
  67   *(markOop*)(((char*)mem) + mark_offset_in_bytes()) = m;
  68 }
  69 
  70 void oopDesc::release_set_mark(markOop m) {
  71   HeapAccess<MO_RELEASE>::store_at(as_oop(), mark_offset_in_bytes(), m);
  72 }
  73 
  74 markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
  75   return HeapAccess<>::atomic_cmpxchg_at(new_mark, as_oop(), mark_offset_in_bytes(), old_mark);
  76 }
  77 
  78 markOop oopDesc::cas_set_mark_raw(markOop new_mark, markOop old_mark, atomic_memory_order order) {
  79   return Atomic::cmpxchg(new_mark, &_mark, old_mark, order);
  80 }
  81 
  82 void oopDesc::init_mark() {
  83   set_mark(markOopDesc::prototype_for_object(this));
  84 }
  85 
  86 void oopDesc::init_mark_raw() {
  87   set_mark_raw(markOopDesc::prototype_for_object(this));
  88 }
  89 
  90 narrowKlass oopDesc::compressed_klass_mask() { return ((narrowKlass) 1 << narrow_storage_props_shift) - 1; }
  91 uintptr_t   oopDesc::klass_mask()   { return ((uintptr_t) 1 << wide_storage_props_shift) - 1; }
  92 
  93 narrowKlass oopDesc::compressed_klass_masked(narrowKlass raw) { return raw & compressed_klass_mask(); }
  94 Klass*      oopDesc::klass_masked(uintptr_t raw)     { return reinterpret_cast<Klass*>(raw & klass_mask()); }
  95 
  96 
  97 Klass* oopDesc::klass() const {
  98   if (UseCompressedClassPointers) {
  99     return CompressedKlassPointers::decode_not_null(compressed_klass_masked(_metadata._compressed_klass));
 100   } else {
 101     return klass_masked(_metadata._wide_storage_props);
 102   }
 103 }
 104 
 105 Klass* oopDesc::klass_or_null() const volatile {
 106   if (UseCompressedClassPointers) {
 107     return CompressedKlassPointers::decode(compressed_klass_masked(_metadata._compressed_klass));
 108   } else {
 109     return klass_masked(_metadata._wide_storage_props);
 110   }
 111 }
 112 
 113 Klass* oopDesc::klass_or_null_acquire() const volatile {
 114   if (UseCompressedClassPointers) {
 115     // Workaround for non-const load_acquire parameter.
 116     const volatile narrowKlass* addr = &_metadata._compressed_klass;
 117     volatile narrowKlass* xaddr = const_cast<volatile narrowKlass*>(addr);
 118     return CompressedKlassPointers::decode(compressed_klass_masked(OrderAccess::load_acquire(xaddr)));
 119   } else {
 120     return klass_masked(OrderAccess::load_acquire(&_metadata._wide_storage_props));
 121   }
 122 }
 123 
 124 Klass** oopDesc::klass_addr(HeapWord* mem) {
 125   // Only used internally and with CMS and will not work with
 126   // UseCompressedOops
 127   assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
 128   ByteSize offset = byte_offset_of(oopDesc, _metadata._klass);
 129   return (Klass**) (((char*)mem) + in_bytes(offset));
 130 }
 131 
 132 uintptr_t* oopDesc::wide_metadata_addr(HeapWord* mem) {
 133   assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
 134   ByteSize offset = byte_offset_of(oopDesc, _metadata._wide_storage_props);
 135   return (uintptr_t*) (((char*)mem) + in_bytes(offset));
 136 }
 137 
 138 narrowKlass* oopDesc::compressed_klass_addr(HeapWord* mem) {
 139   assert(UseCompressedClassPointers, "only called by compressed klass pointers");
 140   ByteSize offset = byte_offset_of(oopDesc, _metadata._compressed_klass);
 141   return (narrowKlass*) (((char*)mem) + in_bytes(offset));
 142 }
 143 
 144 Klass** oopDesc::klass_addr() {
 145   return klass_addr((HeapWord*)this);
 146 }
 147 
 148 narrowKlass* oopDesc::compressed_klass_addr() {
 149   return compressed_klass_addr((HeapWord*)this);
 150 }
 151 
 152 #define CHECK_SET_KLASS(k)                                                \
 153   do {                                                                    \
 154     assert(Universe::is_bootstrapping() || k != NULL, "NULL Klass");      \
 155     assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass"); \
 156     assert(((reinterpret_cast<uintptr_t>(k) & (~ oopDesc::klass_mask())) == 0), \
 157       "No room for storage props "); \
 158   } while (0)
 159 
 160 void oopDesc::set_klass(Klass* k) {
 161   CHECK_SET_KLASS(k);
 162   if (UseCompressedClassPointers) {
 163     *compressed_klass_addr() = CompressedKlassPointers::encode_not_null(k);
 164   } else {
 165     *klass_addr() = k;
 166   }
 167 }
 168 
 169 void oopDesc::release_set_klass(HeapWord* mem, Klass* klass) {
 170   CHECK_SET_KLASS(klass);
 171   if (UseCompressedClassPointers) {
 172     OrderAccess::release_store(compressed_klass_addr(mem),
 173                                CompressedKlassPointers::encode_not_null(klass));
 174   } else {
 175     OrderAccess::release_store(klass_addr(mem), klass);
 176   }
 177   assert(((oopDesc*)mem)->klass() == klass, "failed oopDesc::klass() encode/decode");
 178 }
 179 
 180 void oopDesc::set_metadata(ArrayStorageProperties storage_props, Klass* klass) {
 181   CHECK_SET_KLASS(klass);
 182   if (UseCompressedClassPointers) {
 183     *compressed_klass_addr() = (CompressedKlassPointers::encode_not_null(klass) | storage_props.encode<narrowKlass>(narrow_storage_props_shift));
 184   } else {
 185     *wide_metadata_addr((HeapWord*)this) = (reinterpret_cast<uintptr_t>(klass) | storage_props.encode<uintptr_t>(wide_storage_props_shift));
 186   }
 187 }
 188 
 189 void oopDesc::release_set_metadata(HeapWord* mem, ArrayStorageProperties storage_props, Klass* klass) {
 190   CHECK_SET_KLASS(klass);
 191   if (UseCompressedClassPointers) {
 192     OrderAccess::release_store(oopDesc::compressed_klass_addr(mem),
 193                                CompressedKlassPointers::encode_not_null(klass) | storage_props.encode<narrowKlass>(narrow_storage_props_shift));
 194   } else {
 195     OrderAccess::release_store(oopDesc::wide_metadata_addr(mem),
 196                                (reinterpret_cast<uintptr_t>(klass) | storage_props.encode<uintptr_t>(wide_storage_props_shift)));
 197   }
 198 }
 199 #undef CHECK_SET_KLASS
 200 
 201 
 202 ArrayStorageProperties oopDesc::array_storage_properties() const {
 203   if (UseCompressedClassPointers) {
 204     return ArrayStorageProperties(_metadata._narrow_storage_props >> narrow_storage_props_shift);
 205   } else {
 206     return ArrayStorageProperties(_metadata._wide_storage_props >> wide_storage_props_shift);
 207   }
 208 }
 209 
 210 
 211 int oopDesc::klass_gap() const {
 212   return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
 213 }
 214 
 215 void oopDesc::set_klass_gap(HeapWord* mem, int v) {
 216   if (UseCompressedClassPointers) {
 217     *(int*)(((char*)mem) + klass_gap_offset_in_bytes()) = v;
 218   }
 219 }
 220 
 221 void oopDesc::set_klass_gap(int v) {
 222   set_klass_gap((HeapWord*)this, v);
 223 }
 224 
 225 void oopDesc::set_klass_to_list_ptr(oop k) {
 226   // This is only to be used during GC, for from-space objects, so no
 227   // barrier is needed.
 228   if (UseCompressedClassPointers) {
 229     _metadata._compressed_klass = (narrowKlass)CompressedOops::encode(k);  // may be null (parnew overflow handling)
 230   } else {
 231     _metadata._klass = (Klass*)(address)k;
 232   }
 233 }
 234 
 235 oop oopDesc::list_ptr_from_klass() {
 236   // This is only to be used during GC, for from-space objects.
 237   if (UseCompressedClassPointers) {
 238     return CompressedOops::decode((narrowOop)_metadata._compressed_klass);
 239   } else {
 240     // Special case for GC
 241     return (oop)(address)_metadata._klass;
 242   }
 243 }
 244 
 245 bool oopDesc::is_a(Klass* k) const {
 246   return klass()->is_subtype_of(k);
 247 }
 248 
 249 int oopDesc::size()  {
 250   return size_given_klass(klass());
 251 }
 252 
 253 int oopDesc::size_given_klass(Klass* klass)  {
 254   int lh = klass->layout_helper();
 255   int s;
 256 
 257   // lh is now a value computed at class initialization that may hint
 258   // at the size.  For instances, this is positive and equal to the
 259   // size.  For arrays, this is negative and provides log2 of the
 260   // array element size.  For other oops, it is zero and thus requires
 261   // a virtual call.
 262   //
 263   // We go to all this trouble because the size computation is at the
 264   // heart of phase 2 of mark-compaction, and called for every object,
 265   // alive or dead.  So the speed here is equal in importance to the
 266   // speed of allocation.
 267 
 268   if (lh > Klass::_lh_neutral_value) {
 269     if (!Klass::layout_helper_needs_slow_path(lh)) {
 270       s = lh >> LogHeapWordSize;  // deliver size scaled by wordSize
 271     } else {
 272       s = klass->oop_size(this);
 273     }
 274   } else if (lh <= Klass::_lh_neutral_value) {
 275     // The most common case is instances; fall through if so.
 276     if (lh < Klass::_lh_neutral_value) {
 277       // Second most common case is arrays.  We have to fetch the
 278       // length of the array, shift (multiply) it appropriately,
 279       // up to wordSize, add the header, and align to object size.
 280       size_t size_in_bytes;
 281       size_t array_length = (size_t) ((arrayOop)this)->length();
 282       size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
 283       size_in_bytes += Klass::layout_helper_header_size(lh);
 284 
 285       // This code could be simplified, but by keeping array_header_in_bytes
 286       // in units of bytes and doing it this way we can round up just once,
 287       // skipping the intermediate round to HeapWordSize.
 288       s = (int)(align_up(size_in_bytes, MinObjAlignmentInBytes) / HeapWordSize);
 289 
 290       // ParNew (used by CMS), UseParallelGC and UseG1GC can change the length field
 291       // of an "old copy" of an object array in the young gen so it indicates
 292       // the grey portion of an already copied array. This will cause the first
 293       // disjunct below to fail if the two comparands are computed across such
 294       // a concurrent change.
 295       // ParNew also runs with promotion labs (which look like int
 296       // filler arrays) which are subject to changing their declared size
 297       // when finally retiring a PLAB; this also can cause the first disjunct
 298       // to fail for another worker thread that is concurrently walking the block
 299       // offset table. Both these invariant failures are benign for their
 300       // current uses; we relax the assertion checking to cover these two cases below:
 301       //     is_objArray() && is_forwarded()   // covers first scenario above
 302       //  || is_typeArray()                    // covers second scenario above
 303       // If and when UseParallelGC uses the same obj array oop stealing/chunking
 304       // technique, we will need to suitably modify the assertion.
 305       assert((s == klass->oop_size(this)) ||
 306              (Universe::heap()->is_gc_active() &&
 307               ((is_typeArray() && UseConcMarkSweepGC) ||
 308                (is_objArray()  && is_forwarded() && (UseConcMarkSweepGC || UseParallelGC || UseG1GC)))),
 309              "wrong array object size");
 310     } else {
 311       // Must be zero, so bite the bullet and take the virtual call.
 312       s = klass->oop_size(this);
 313     }
 314   }
 315 
 316   assert(s > 0, "Oop size must be greater than zero, not %d", s);
 317   assert(is_object_aligned(s), "Oop size is not properly aligned: %d", s);
 318   return s;
 319 }
 320 
 321 bool oopDesc::is_instance()  const { return klass()->is_instance_klass();  }
 322 bool oopDesc::is_array()     const { return klass()->is_array_klass();     }
 323 bool oopDesc::is_objArray()  const { return klass()->is_objArray_klass();  }
 324 bool oopDesc::is_typeArray() const { return klass()->is_typeArray_klass(); }
 325 bool oopDesc::is_value()     const { return klass()->is_value(); }
 326 bool oopDesc::is_valueArray()  const { return klass()->is_valueArray_klass(); }
 327 
 328 void*    oopDesc::field_addr_raw(int offset)     const { return reinterpret_cast<void*>(cast_from_oop<intptr_t>(as_oop()) + offset); }
 329 void*    oopDesc::field_addr(int offset)         const { return Access<>::resolve(as_oop())->field_addr_raw(offset); }
 330 
 331 template <class T>
 332 T*       oopDesc::obj_field_addr_raw(int offset) const { return (T*) field_addr_raw(offset); }
 333 
 334 template <typename T>
 335 size_t   oopDesc::field_offset(T* p) const { return pointer_delta((void*)p, (void*)this, 1); }
 336 
 337 template <DecoratorSet decorators>
 338 inline oop  oopDesc::obj_field_access(int offset) const             { return HeapAccess<decorators>::oop_load_at(as_oop(), offset); }
 339 inline oop  oopDesc::obj_field(int offset) const                    { return HeapAccess<>::oop_load_at(as_oop(), offset);  }
 340 
 341 inline void oopDesc::obj_field_put(int offset, oop value)           { HeapAccess<>::oop_store_at(as_oop(), offset, value); }
 342 
 343 inline jbyte oopDesc::byte_field(int offset) const                  { return HeapAccess<>::load_at(as_oop(), offset);  }
 344 inline void  oopDesc::byte_field_put(int offset, jbyte value)       { HeapAccess<>::store_at(as_oop(), offset, value); }
 345 
 346 inline jchar oopDesc::char_field(int offset) const                  { return HeapAccess<>::load_at(as_oop(), offset);  }
 347 inline void  oopDesc::char_field_put(int offset, jchar value)       { HeapAccess<>::store_at(as_oop(), offset, value); }
 348 
 349 inline jboolean oopDesc::bool_field(int offset) const               { return HeapAccess<>::load_at(as_oop(), offset);                }
 350 inline void     oopDesc::bool_field_put(int offset, jboolean value) { HeapAccess<>::store_at(as_oop(), offset, jboolean(value & 1)); }
 351 
 352 inline jshort oopDesc::short_field(int offset) const                { return HeapAccess<>::load_at(as_oop(), offset);  }
 353 inline void   oopDesc::short_field_put(int offset, jshort value)    { HeapAccess<>::store_at(as_oop(), offset, value); }
 354 
 355 inline jint oopDesc::int_field(int offset) const                    { return HeapAccess<>::load_at(as_oop(), offset);  }
 356 inline jint oopDesc::int_field_raw(int offset) const                { return RawAccess<>::load_at(as_oop(), offset);   }
 357 inline void oopDesc::int_field_put(int offset, jint value)          { HeapAccess<>::store_at(as_oop(), offset, value); }
 358 
 359 inline jlong oopDesc::long_field(int offset) const                  { return HeapAccess<>::load_at(as_oop(), offset);  }
 360 inline void  oopDesc::long_field_put(int offset, jlong value)       { HeapAccess<>::store_at(as_oop(), offset, value); }
 361 
 362 inline jfloat oopDesc::float_field(int offset) const                { return HeapAccess<>::load_at(as_oop(), offset);  }
 363 inline void   oopDesc::float_field_put(int offset, jfloat value)    { HeapAccess<>::store_at(as_oop(), offset, value); }
 364 
 365 inline jdouble oopDesc::double_field(int offset) const              { return HeapAccess<>::load_at(as_oop(), offset);  }
 366 inline void    oopDesc::double_field_put(int offset, jdouble value) { HeapAccess<>::store_at(as_oop(), offset, value); }
 367 
 368 bool oopDesc::is_locked() const {
 369   return mark()->is_locked();
 370 }
 371 
 372 bool oopDesc::is_unlocked() const {
 373   return mark()->is_unlocked();
 374 }
 375 
 376 bool oopDesc::has_bias_pattern() const {
 377   return mark()->has_bias_pattern();
 378 }
 379 
 380 
 381 bool oopDesc::has_bias_pattern_raw() const {
 382   return mark_raw()->has_bias_pattern();
 383 }
 384 
 385 // Used only for markSweep, scavenging
 386 bool oopDesc::is_gc_marked() const {
 387   return mark_raw()->is_marked();
 388 }
 389 
 390 // Used by scavengers
 391 bool oopDesc::is_forwarded() const {
 392   // The extra heap check is needed since the obj might be locked, in which case the
 393   // mark would point to a stack location and have the sentinel bit cleared
 394   return mark_raw()->is_marked();
 395 }
 396 
 397 // Used by scavengers
 398 void oopDesc::forward_to(oop p) {
 399   assert(check_obj_alignment(p),
 400          "forwarding to something not aligned");
 401   assert(Universe::heap()->is_in_reserved(p),
 402          "forwarding to something not in heap");
 403   assert(!is_archived_object(oop(this)) &&
 404          !is_archived_object(p),
 405          "forwarding archive object");
 406   markOop m = markOopDesc::encode_pointer_as_mark(p);
 407   assert(m->decode_pointer() == p, "encoding must be reversable");
 408   set_mark_raw(m);
 409 }
 410 
 411 // Used by parallel scavengers
 412 bool oopDesc::cas_forward_to(oop p, markOop compare, atomic_memory_order order) {
 413   assert(check_obj_alignment(p),
 414          "forwarding to something not aligned");
 415   assert(Universe::heap()->is_in_reserved(p),
 416          "forwarding to something not in heap");
 417   markOop m = markOopDesc::encode_pointer_as_mark(p);
 418   assert(m->decode_pointer() == p, "encoding must be reversable");
 419   return cas_set_mark_raw(m, compare, order) == compare;
 420 }
 421 
 422 oop oopDesc::forward_to_atomic(oop p, markOop compare, atomic_memory_order order) {
 423   // CMS forwards some non-heap value into the mark oop to reserve oops during
 424   // promotion, so the next two asserts do not hold.
 425   assert(UseConcMarkSweepGC || check_obj_alignment(p),
 426          "forwarding to something not aligned");
 427   assert(UseConcMarkSweepGC || Universe::heap()->is_in_reserved(p),
 428          "forwarding to something not in heap");
 429   markOop m = markOopDesc::encode_pointer_as_mark(p);
 430   assert(m->decode_pointer() == p, "encoding must be reversable");
 431   markOop old_mark = cas_set_mark_raw(m, compare, order);
 432   if (old_mark == compare) {
 433     return NULL;
 434   } else {
 435     return (oop)old_mark->decode_pointer();
 436   }
 437 }
 438 
 439 // Note that the forwardee is not the same thing as the displaced_mark.
 440 // The forwardee is used when copying during scavenge and mark-sweep.
 441 // It does need to clear the low two locking- and GC-related bits.
 442 oop oopDesc::forwardee() const {
 443   return (oop) mark_raw()->decode_pointer();
 444 }
 445 
 446 // Note that the forwardee is not the same thing as the displaced_mark.
 447 // The forwardee is used when copying during scavenge and mark-sweep.
 448 // It does need to clear the low two locking- and GC-related bits.
 449 oop oopDesc::forwardee_acquire() const {
 450   markOop m = OrderAccess::load_acquire(&_mark);
 451   return (oop) m->decode_pointer();
 452 }
 453 
 454 // The following method needs to be MT safe.
 455 uint oopDesc::age() const {
 456   assert(!is_forwarded(), "Attempt to read age from forwarded mark");
 457   if (has_displaced_mark_raw()) {
 458     return displaced_mark_raw()->age();
 459   } else {
 460     return mark_raw()->age();
 461   }
 462 }
 463 
 464 void oopDesc::incr_age() {
 465   assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
 466   if (has_displaced_mark_raw()) {
 467     set_displaced_mark_raw(displaced_mark_raw()->incr_age());
 468   } else {
 469     set_mark_raw(mark_raw()->incr_age());
 470   }
 471 }
 472 
 473 template <typename OopClosureType>
 474 void oopDesc::oop_iterate(OopClosureType* cl) {
 475   OopIteratorClosureDispatch::oop_oop_iterate(cl, this, klass());
 476 }
 477 
 478 template <typename OopClosureType>
 479 void oopDesc::oop_iterate(OopClosureType* cl, MemRegion mr) {
 480   OopIteratorClosureDispatch::oop_oop_iterate(cl, this, klass(), mr);
 481 }
 482 
 483 template <typename OopClosureType>
 484 int oopDesc::oop_iterate_size(OopClosureType* cl) {
 485   Klass* k = klass();
 486   int size = size_given_klass(k);
 487   OopIteratorClosureDispatch::oop_oop_iterate(cl, this, k);
 488   return size;
 489 }
 490 
 491 template <typename OopClosureType>
 492 int oopDesc::oop_iterate_size(OopClosureType* cl, MemRegion mr) {
 493   Klass* k = klass();
 494   int size = size_given_klass(k);
 495   OopIteratorClosureDispatch::oop_oop_iterate(cl, this, k, mr);
 496   return size;
 497 }
 498 
 499 template <typename OopClosureType>
 500 void oopDesc::oop_iterate_backwards(OopClosureType* cl) {
 501   OopIteratorClosureDispatch::oop_oop_iterate_backwards(cl, this, klass());
 502 }
 503 
 504 bool oopDesc::is_instanceof_or_null(oop obj, Klass* klass) {
 505   return obj == NULL || obj->klass()->is_subtype_of(klass);
 506 }
 507 
 508 intptr_t oopDesc::identity_hash() {
 509   // Fast case; if the object is unlocked and the hash value is set, no locking is needed
 510   // Note: The mark must be read into local variable to avoid concurrent updates.
 511   markOop mrk = mark();
 512   if (mrk->is_unlocked() && !mrk->has_no_hash()) {
 513     return mrk->hash();
 514   } else if (mrk->is_marked()) {
 515     return mrk->hash();
 516   } else {
 517     return slow_identity_hash();
 518   }
 519 }
 520 
 521 bool oopDesc::has_displaced_mark_raw() const {
 522   return mark_raw()->has_displaced_mark_helper();
 523 }
 524 
 525 markOop oopDesc::displaced_mark_raw() const {
 526   return mark_raw()->displaced_mark_helper();
 527 }
 528 
 529 void oopDesc::set_displaced_mark_raw(markOop m) {
 530   mark_raw()->set_displaced_mark_helper(m);
 531 }
 532 
 533 #endif // SHARE_OOPS_OOP_INLINE_HPP