src/share/vm/oops/oop.inline.hpp

Thu, 27 Feb 2014 10:36:50 +0100

author
stefank
date
Thu, 27 Feb 2014 10:36:50 +0100
changeset 6976
76b588255908
parent 6911
ce8f6bb717c9
child 7535
7ae4e26cb1e0
child 8368
32b682649973
permissions
-rw-r--r--

8035746: Add missing Klass::oop_is_instanceClassLoader() function
Reviewed-by: mgerdin, coleenp

     1 /*
     2  * Copyright (c) 1997, 2014, 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  */
    25 #ifndef SHARE_VM_OOPS_OOP_INLINE_HPP
    26 #define SHARE_VM_OOPS_OOP_INLINE_HPP
    28 #include "gc_implementation/shared/ageTable.hpp"
    29 #include "gc_implementation/shared/markSweep.inline.hpp"
    30 #include "gc_interface/collectedHeap.inline.hpp"
    31 #include "memory/barrierSet.inline.hpp"
    32 #include "memory/cardTableModRefBS.hpp"
    33 #include "memory/genCollectedHeap.hpp"
    34 #include "memory/generation.hpp"
    35 #include "memory/specialized_oop_closures.hpp"
    36 #include "oops/arrayKlass.hpp"
    37 #include "oops/arrayOop.hpp"
    38 #include "oops/klass.inline.hpp"
    39 #include "oops/markOop.inline.hpp"
    40 #include "oops/oop.hpp"
    41 #include "runtime/atomic.inline.hpp"
    42 #include "runtime/orderAccess.inline.hpp"
    43 #include "runtime/os.hpp"
    44 #include "utilities/macros.hpp"
    45 #ifdef TARGET_ARCH_x86
    46 # include "bytes_x86.hpp"
    47 #endif
    48 #ifdef TARGET_ARCH_sparc
    49 # include "bytes_sparc.hpp"
    50 #endif
    51 #ifdef TARGET_ARCH_zero
    52 # include "bytes_zero.hpp"
    53 #endif
    54 #ifdef TARGET_ARCH_arm
    55 # include "bytes_arm.hpp"
    56 #endif
    57 #ifdef TARGET_ARCH_ppc
    58 # include "bytes_ppc.hpp"
    59 #endif
    61 // Implementation of all inlined member functions defined in oop.hpp
    62 // We need a separate file to avoid circular references
    64 inline void oopDesc::release_set_mark(markOop m) {
    65   OrderAccess::release_store_ptr(&_mark, m);
    66 }
    68 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
    69   return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
    70 }
    72 inline Klass* oopDesc::klass() const {
    73   if (UseCompressedClassPointers) {
    74     return Klass::decode_klass_not_null(_metadata._compressed_klass);
    75   } else {
    76     return _metadata._klass;
    77   }
    78 }
    80 inline Klass* oopDesc::klass_or_null() const volatile {
    81   // can be NULL in CMS
    82   if (UseCompressedClassPointers) {
    83     return Klass::decode_klass(_metadata._compressed_klass);
    84   } else {
    85     return _metadata._klass;
    86   }
    87 }
    89 inline int oopDesc::klass_gap_offset_in_bytes() {
    90   assert(UseCompressedClassPointers, "only applicable to compressed klass pointers");
    91   return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass);
    92 }
    94 inline Klass** oopDesc::klass_addr() {
    95   // Only used internally and with CMS and will not work with
    96   // UseCompressedOops
    97   assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
    98   return (Klass**) &_metadata._klass;
    99 }
   101 inline narrowKlass* oopDesc::compressed_klass_addr() {
   102   assert(UseCompressedClassPointers, "only called by compressed klass pointers");
   103   return &_metadata._compressed_klass;
   104 }
   106 inline void oopDesc::set_klass(Klass* k) {
   107   // since klasses are promoted no store check is needed
   108   assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*");
   109   assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*");
   110   if (UseCompressedClassPointers) {
   111     *compressed_klass_addr() = Klass::encode_klass_not_null(k);
   112   } else {
   113     *klass_addr() = k;
   114   }
   115 }
   117 inline int oopDesc::klass_gap() const {
   118   return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
   119 }
   121 inline void oopDesc::set_klass_gap(int v) {
   122   if (UseCompressedClassPointers) {
   123     *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
   124   }
   125 }
   127 inline void oopDesc::set_klass_to_list_ptr(oop k) {
   128   // This is only to be used during GC, for from-space objects, so no
   129   // barrier is needed.
   130   if (UseCompressedClassPointers) {
   131     _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k);  // may be null (parnew overflow handling)
   132   } else {
   133     _metadata._klass = (Klass*)(address)k;
   134   }
   135 }
   137 inline oop oopDesc::list_ptr_from_klass() {
   138   // This is only to be used during GC, for from-space objects.
   139   if (UseCompressedClassPointers) {
   140     return decode_heap_oop((narrowOop)_metadata._compressed_klass);
   141   } else {
   142     // Special case for GC
   143     return (oop)(address)_metadata._klass;
   144   }
   145 }
   147 inline void   oopDesc::init_mark()                 { set_mark(markOopDesc::prototype_for_object(this)); }
   149 inline bool oopDesc::is_a(Klass* k)        const { return klass()->is_subtype_of(k); }
   151 inline bool oopDesc::is_instance()            const { return klass()->oop_is_instance(); }
   152 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); }
   153 inline bool oopDesc::is_instanceMirror()      const { return klass()->oop_is_instanceMirror(); }
   154 inline bool oopDesc::is_instanceRef()         const { return klass()->oop_is_instanceRef(); }
   155 inline bool oopDesc::is_array()               const { return klass()->oop_is_array(); }
   156 inline bool oopDesc::is_objArray()            const { return klass()->oop_is_objArray(); }
   157 inline bool oopDesc::is_typeArray()           const { return klass()->oop_is_typeArray(); }
   159 inline void*     oopDesc::field_base(int offset)        const { return (void*)&((char*)this)[offset]; }
   161 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
   162 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
   163 inline jbyte*    oopDesc::byte_field_addr(int offset)   const { return (jbyte*)   field_base(offset); }
   164 inline jchar*    oopDesc::char_field_addr(int offset)   const { return (jchar*)   field_base(offset); }
   165 inline jboolean* oopDesc::bool_field_addr(int offset)   const { return (jboolean*)field_base(offset); }
   166 inline jint*     oopDesc::int_field_addr(int offset)    const { return (jint*)    field_base(offset); }
   167 inline jshort*   oopDesc::short_field_addr(int offset)  const { return (jshort*)  field_base(offset); }
   168 inline jlong*    oopDesc::long_field_addr(int offset)   const { return (jlong*)   field_base(offset); }
   169 inline jfloat*   oopDesc::float_field_addr(int offset)  const { return (jfloat*)  field_base(offset); }
   170 inline jdouble*  oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
   171 inline address*  oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
   174 // Functions for getting and setting oops within instance objects.
   175 // If the oops are compressed, the type passed to these overloaded functions
   176 // is narrowOop.  All functions are overloaded so they can be called by
   177 // template functions without conditionals (the compiler instantiates via
   178 // the right type and inlines the appopriate code).
   180 inline bool oopDesc::is_null(oop obj)       { return obj == NULL; }
   181 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
   183 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
   184 // offset from the heap base.  Saving the check for null can save instructions
   185 // in inner GC loops so these are separated.
   187 inline bool check_obj_alignment(oop obj) {
   188   return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
   189 }
   191 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
   192   assert(!is_null(v), "oop value can never be zero");
   193   assert(check_obj_alignment(v), "Address not aligned");
   194   assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
   195   address base = Universe::narrow_oop_base();
   196   int    shift = Universe::narrow_oop_shift();
   197   uint64_t  pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
   198   assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
   199   uint64_t result = pd >> shift;
   200   assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
   201   assert(decode_heap_oop(result) == v, "reversibility");
   202   return (narrowOop)result;
   203 }
   205 inline narrowOop oopDesc::encode_heap_oop(oop v) {
   206   return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
   207 }
   209 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
   210   assert(!is_null(v), "narrow oop value can never be zero");
   211   address base = Universe::narrow_oop_base();
   212   int    shift = Universe::narrow_oop_shift();
   213   oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
   214   assert(check_obj_alignment(result), err_msg("address not aligned: " INTPTR_FORMAT, p2i((void*) result)));
   215   return result;
   216 }
   218 inline oop oopDesc::decode_heap_oop(narrowOop v) {
   219   return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
   220 }
   222 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
   223 inline oop oopDesc::decode_heap_oop(oop v)  { return v; }
   225 // Load an oop out of the Java heap as is without decoding.
   226 // Called by GC to check for null before decoding.
   227 inline oop       oopDesc::load_heap_oop(oop* p)          { return *p; }
   228 inline narrowOop oopDesc::load_heap_oop(narrowOop* p)    { return *p; }
   230 // Load and decode an oop out of the Java heap into a wide oop.
   231 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p)       { return *p; }
   232 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
   233   return decode_heap_oop_not_null(*p);
   234 }
   236 // Load and decode an oop out of the heap accepting null
   237 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
   238 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
   239   return decode_heap_oop(*p);
   240 }
   242 // Store already encoded heap oop into the heap.
   243 inline void oopDesc::store_heap_oop(oop* p, oop v)                 { *p = v; }
   244 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v)     { *p = v; }
   246 // Encode and store a heap oop.
   247 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
   248   *p = encode_heap_oop_not_null(v);
   249 }
   250 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
   252 // Encode and store a heap oop allowing for null.
   253 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
   254   *p = encode_heap_oop(v);
   255 }
   256 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
   258 // Store heap oop as is for volatile fields.
   259 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
   260   OrderAccess::release_store_ptr(p, v);
   261 }
   262 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
   263                                             narrowOop v) {
   264   OrderAccess::release_store(p, v);
   265 }
   267 inline void oopDesc::release_encode_store_heap_oop_not_null(
   268                                                 volatile narrowOop* p, oop v) {
   269   // heap oop is not pointer sized.
   270   OrderAccess::release_store(p, encode_heap_oop_not_null(v));
   271 }
   273 inline void oopDesc::release_encode_store_heap_oop_not_null(
   274                                                       volatile oop* p, oop v) {
   275   OrderAccess::release_store_ptr(p, v);
   276 }
   278 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
   279                                                            oop v) {
   280   OrderAccess::release_store_ptr(p, v);
   281 }
   282 inline void oopDesc::release_encode_store_heap_oop(
   283                                                 volatile narrowOop* p, oop v) {
   284   OrderAccess::release_store(p, encode_heap_oop(v));
   285 }
   288 // These functions are only used to exchange oop fields in instances,
   289 // not headers.
   290 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
   291   if (UseCompressedOops) {
   292     // encode exchange value from oop to T
   293     narrowOop val = encode_heap_oop(exchange_value);
   294     narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
   295     // decode old from T to oop
   296     return decode_heap_oop(old);
   297   } else {
   298     return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
   299   }
   300 }
   302 // In order to put or get a field out of an instance, must first check
   303 // if the field has been compressed and uncompress it.
   304 inline oop oopDesc::obj_field(int offset) const {
   305   return UseCompressedOops ?
   306     load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
   307     load_decode_heap_oop(obj_field_addr<oop>(offset));
   308 }
   309 inline volatile oop oopDesc::obj_field_volatile(int offset) const {
   310   volatile oop value = obj_field(offset);
   311   OrderAccess::acquire();
   312   return value;
   313 }
   314 inline void oopDesc::obj_field_put(int offset, oop value) {
   315   UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
   316                       oop_store(obj_field_addr<oop>(offset),       value);
   317 }
   319 inline Metadata* oopDesc::metadata_field(int offset) const {
   320   return *metadata_field_addr(offset);
   321 }
   323 inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
   324   *metadata_field_addr(offset) = value;
   325 }
   327 inline void oopDesc::obj_field_put_raw(int offset, oop value) {
   328   UseCompressedOops ?
   329     encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
   330     encode_store_heap_oop(obj_field_addr<oop>(offset),       value);
   331 }
   332 inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
   333   OrderAccess::release();
   334   obj_field_put(offset, value);
   335   OrderAccess::fence();
   336 }
   338 inline jbyte oopDesc::byte_field(int offset) const                  { return (jbyte) *byte_field_addr(offset);    }
   339 inline void oopDesc::byte_field_put(int offset, jbyte contents)     { *byte_field_addr(offset) = (jint) contents; }
   341 inline jboolean oopDesc::bool_field(int offset) const               { return (jboolean) *bool_field_addr(offset); }
   342 inline void oopDesc::bool_field_put(int offset, jboolean contents)  { *bool_field_addr(offset) = (jint) contents; }
   344 inline jchar oopDesc::char_field(int offset) const                  { return (jchar) *char_field_addr(offset);    }
   345 inline void oopDesc::char_field_put(int offset, jchar contents)     { *char_field_addr(offset) = (jint) contents; }
   347 inline jint oopDesc::int_field(int offset) const                    { return *int_field_addr(offset);        }
   348 inline void oopDesc::int_field_put(int offset, jint contents)       { *int_field_addr(offset) = contents;    }
   350 inline jshort oopDesc::short_field(int offset) const                { return (jshort) *short_field_addr(offset);  }
   351 inline void oopDesc::short_field_put(int offset, jshort contents)   { *short_field_addr(offset) = (jint) contents;}
   353 inline jlong oopDesc::long_field(int offset) const                  { return *long_field_addr(offset);       }
   354 inline void oopDesc::long_field_put(int offset, jlong contents)     { *long_field_addr(offset) = contents;   }
   356 inline jfloat oopDesc::float_field(int offset) const                { return *float_field_addr(offset);      }
   357 inline void oopDesc::float_field_put(int offset, jfloat contents)   { *float_field_addr(offset) = contents;  }
   359 inline jdouble oopDesc::double_field(int offset) const              { return *double_field_addr(offset);     }
   360 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
   362 inline address oopDesc::address_field(int offset) const              { return *address_field_addr(offset);     }
   363 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
   365 inline oop oopDesc::obj_field_acquire(int offset) const {
   366   return UseCompressedOops ?
   367              decode_heap_oop((narrowOop)
   368                OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
   369            : decode_heap_oop((oop)
   370                OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
   371 }
   372 inline void oopDesc::release_obj_field_put(int offset, oop value) {
   373   UseCompressedOops ?
   374     oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
   375     oop_store((volatile oop*)      obj_field_addr<oop>(offset),       value);
   376 }
   378 inline jbyte oopDesc::byte_field_acquire(int offset) const                  { return OrderAccess::load_acquire(byte_field_addr(offset));     }
   379 inline void oopDesc::release_byte_field_put(int offset, jbyte contents)     { OrderAccess::release_store(byte_field_addr(offset), contents); }
   381 inline jboolean oopDesc::bool_field_acquire(int offset) const               { return OrderAccess::load_acquire(bool_field_addr(offset));     }
   382 inline void oopDesc::release_bool_field_put(int offset, jboolean contents)  { OrderAccess::release_store(bool_field_addr(offset), contents); }
   384 inline jchar oopDesc::char_field_acquire(int offset) const                  { return OrderAccess::load_acquire(char_field_addr(offset));     }
   385 inline void oopDesc::release_char_field_put(int offset, jchar contents)     { OrderAccess::release_store(char_field_addr(offset), contents); }
   387 inline jint oopDesc::int_field_acquire(int offset) const                    { return OrderAccess::load_acquire(int_field_addr(offset));      }
   388 inline void oopDesc::release_int_field_put(int offset, jint contents)       { OrderAccess::release_store(int_field_addr(offset), contents);  }
   390 inline jshort oopDesc::short_field_acquire(int offset) const                { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
   391 inline void oopDesc::release_short_field_put(int offset, jshort contents)   { OrderAccess::release_store(short_field_addr(offset), contents);     }
   393 inline jlong oopDesc::long_field_acquire(int offset) const                  { return OrderAccess::load_acquire(long_field_addr(offset));       }
   394 inline void oopDesc::release_long_field_put(int offset, jlong contents)     { OrderAccess::release_store(long_field_addr(offset), contents);   }
   396 inline jfloat oopDesc::float_field_acquire(int offset) const                { return OrderAccess::load_acquire(float_field_addr(offset));      }
   397 inline void oopDesc::release_float_field_put(int offset, jfloat contents)   { OrderAccess::release_store(float_field_addr(offset), contents);  }
   399 inline jdouble oopDesc::double_field_acquire(int offset) const              { return OrderAccess::load_acquire(double_field_addr(offset));     }
   400 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
   402 inline address oopDesc::address_field_acquire(int offset) const             { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
   403 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
   405 inline int oopDesc::size_given_klass(Klass* klass)  {
   406   int lh = klass->layout_helper();
   407   int s;
   409   // lh is now a value computed at class initialization that may hint
   410   // at the size.  For instances, this is positive and equal to the
   411   // size.  For arrays, this is negative and provides log2 of the
   412   // array element size.  For other oops, it is zero and thus requires
   413   // a virtual call.
   414   //
   415   // We go to all this trouble because the size computation is at the
   416   // heart of phase 2 of mark-compaction, and called for every object,
   417   // alive or dead.  So the speed here is equal in importance to the
   418   // speed of allocation.
   420   if (lh > Klass::_lh_neutral_value) {
   421     if (!Klass::layout_helper_needs_slow_path(lh)) {
   422       s = lh >> LogHeapWordSize;  // deliver size scaled by wordSize
   423     } else {
   424       s = klass->oop_size(this);
   425     }
   426   } else if (lh <= Klass::_lh_neutral_value) {
   427     // The most common case is instances; fall through if so.
   428     if (lh < Klass::_lh_neutral_value) {
   429       // Second most common case is arrays.  We have to fetch the
   430       // length of the array, shift (multiply) it appropriately,
   431       // up to wordSize, add the header, and align to object size.
   432       size_t size_in_bytes;
   433 #ifdef _M_IA64
   434       // The Windows Itanium Aug 2002 SDK hoists this load above
   435       // the check for s < 0.  An oop at the end of the heap will
   436       // cause an access violation if this load is performed on a non
   437       // array oop.  Making the reference volatile prohibits this.
   438       // (%%% please explain by what magic the length is actually fetched!)
   439       volatile int *array_length;
   440       array_length = (volatile int *)( (intptr_t)this +
   441                           arrayOopDesc::length_offset_in_bytes() );
   442       assert(array_length > 0, "Integer arithmetic problem somewhere");
   443       // Put into size_t to avoid overflow.
   444       size_in_bytes = (size_t) array_length;
   445       size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
   446 #else
   447       size_t array_length = (size_t) ((arrayOop)this)->length();
   448       size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
   449 #endif
   450       size_in_bytes += Klass::layout_helper_header_size(lh);
   452       // This code could be simplified, but by keeping array_header_in_bytes
   453       // in units of bytes and doing it this way we can round up just once,
   454       // skipping the intermediate round to HeapWordSize.  Cast the result
   455       // of round_to to size_t to guarantee unsigned division == right shift.
   456       s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
   457         HeapWordSize);
   459       // UseParNewGC, UseParallelGC and UseG1GC can change the length field
   460       // of an "old copy" of an object array in the young gen so it indicates
   461       // the grey portion of an already copied array. This will cause the first
   462       // disjunct below to fail if the two comparands are computed across such
   463       // a concurrent change.
   464       // UseParNewGC also runs with promotion labs (which look like int
   465       // filler arrays) which are subject to changing their declared size
   466       // when finally retiring a PLAB; this also can cause the first disjunct
   467       // to fail for another worker thread that is concurrently walking the block
   468       // offset table. Both these invariant failures are benign for their
   469       // current uses; we relax the assertion checking to cover these two cases below:
   470       //     is_objArray() && is_forwarded()   // covers first scenario above
   471       //  || is_typeArray()                    // covers second scenario above
   472       // If and when UseParallelGC uses the same obj array oop stealing/chunking
   473       // technique, we will need to suitably modify the assertion.
   474       assert((s == klass->oop_size(this)) ||
   475              (Universe::heap()->is_gc_active() &&
   476               ((is_typeArray() && UseParNewGC) ||
   477                (is_objArray()  && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
   478              "wrong array object size");
   479     } else {
   480       // Must be zero, so bite the bullet and take the virtual call.
   481       s = klass->oop_size(this);
   482     }
   483   }
   485   assert(s % MinObjAlignment == 0, "alignment check");
   486   assert(s > 0, "Bad size calculated");
   487   return s;
   488 }
   491 inline int oopDesc::size()  {
   492   return size_given_klass(klass());
   493 }
   495 inline void update_barrier_set(void* p, oop v, bool release = false) {
   496   assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
   497   oopDesc::bs()->write_ref_field(p, v, release);
   498 }
   500 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
   501   oopDesc::bs()->write_ref_field_pre(p, v);
   502 }
   504 template <class T> inline void oop_store(T* p, oop v) {
   505   if (always_do_update_barrier) {
   506     oop_store((volatile T*)p, v);
   507   } else {
   508     update_barrier_set_pre(p, v);
   509     oopDesc::encode_store_heap_oop(p, v);
   510     // always_do_update_barrier == false =>
   511     // Either we are at a safepoint (in GC) or CMS is not used. In both
   512     // cases it's unnecessary to mark the card as dirty with release sematics.
   513     update_barrier_set((void*)p, v, false /* release */);  // cast away type
   514   }
   515 }
   517 template <class T> inline void oop_store(volatile T* p, oop v) {
   518   update_barrier_set_pre((T*)p, v);   // cast away volatile
   519   // Used by release_obj_field_put, so use release_store_ptr.
   520   oopDesc::release_encode_store_heap_oop(p, v);
   521   // When using CMS we must mark the card corresponding to p as dirty
   522   // with release sematics to prevent that CMS sees the dirty card but
   523   // not the new value v at p due to reordering of the two
   524   // stores. Note that CMS has a concurrent precleaning phase, where
   525   // it reads the card table while the Java threads are running.
   526   update_barrier_set((void*)p, v, true /* release */);    // cast away type
   527 }
   529 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
   530 // (without having to remember the function name this calls).
   531 inline void oop_store_raw(HeapWord* addr, oop value) {
   532   if (UseCompressedOops) {
   533     oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
   534   } else {
   535     oopDesc::encode_store_heap_oop((oop*)addr, value);
   536   }
   537 }
   539 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
   540                                                 volatile HeapWord *dest,
   541                                                 oop compare_value,
   542                                                 bool prebarrier) {
   543   if (UseCompressedOops) {
   544     if (prebarrier) {
   545       update_barrier_set_pre((narrowOop*)dest, exchange_value);
   546     }
   547     // encode exchange and compare value from oop to T
   548     narrowOop val = encode_heap_oop(exchange_value);
   549     narrowOop cmp = encode_heap_oop(compare_value);
   551     narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
   552     // decode old from T to oop
   553     return decode_heap_oop(old);
   554   } else {
   555     if (prebarrier) {
   556       update_barrier_set_pre((oop*)dest, exchange_value);
   557     }
   558     return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
   559   }
   560 }
   562 // Used only for markSweep, scavenging
   563 inline bool oopDesc::is_gc_marked() const {
   564   return mark()->is_marked();
   565 }
   567 inline bool oopDesc::is_locked() const {
   568   return mark()->is_locked();
   569 }
   571 inline bool oopDesc::is_unlocked() const {
   572   return mark()->is_unlocked();
   573 }
   575 inline bool oopDesc::has_bias_pattern() const {
   576   return mark()->has_bias_pattern();
   577 }
   580 // used only for asserts
   581 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
   582   oop obj = (oop) this;
   583   if (!check_obj_alignment(obj)) return false;
   584   if (!Universe::heap()->is_in_reserved(obj)) return false;
   585   // obj is aligned and accessible in heap
   586   if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
   588   // Header verification: the mark is typically non-NULL. If we're
   589   // at a safepoint, it must not be null.
   590   // Outside of a safepoint, the header could be changing (for example,
   591   // another thread could be inflating a lock on this object).
   592   if (ignore_mark_word) {
   593     return true;
   594   }
   595   if (mark() != NULL) {
   596     return true;
   597   }
   598   return !SafepointSynchronize::is_at_safepoint();
   599 }
   602 // used only for asserts
   603 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
   604   return this == NULL ? true : is_oop(ignore_mark_word);
   605 }
   607 #ifndef PRODUCT
   608 // used only for asserts
   609 inline bool oopDesc::is_unlocked_oop() const {
   610   if (!Universe::heap()->is_in_reserved(this)) return false;
   611   return mark()->is_unlocked();
   612 }
   613 #endif // PRODUCT
   615 inline void oopDesc::follow_contents(void) {
   616   assert (is_gc_marked(), "should be marked");
   617   klass()->oop_follow_contents(this);
   618 }
   620 // Used by scavengers
   622 inline bool oopDesc::is_forwarded() const {
   623   // The extra heap check is needed since the obj might be locked, in which case the
   624   // mark would point to a stack location and have the sentinel bit cleared
   625   return mark()->is_marked();
   626 }
   628 // Used by scavengers
   629 inline void oopDesc::forward_to(oop p) {
   630   assert(check_obj_alignment(p),
   631          "forwarding to something not aligned");
   632   assert(Universe::heap()->is_in_reserved(p),
   633          "forwarding to something not in heap");
   634   markOop m = markOopDesc::encode_pointer_as_mark(p);
   635   assert(m->decode_pointer() == p, "encoding must be reversable");
   636   set_mark(m);
   637 }
   639 // Used by parallel scavengers
   640 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
   641   assert(check_obj_alignment(p),
   642          "forwarding to something not aligned");
   643   assert(Universe::heap()->is_in_reserved(p),
   644          "forwarding to something not in heap");
   645   markOop m = markOopDesc::encode_pointer_as_mark(p);
   646   assert(m->decode_pointer() == p, "encoding must be reversable");
   647   return cas_set_mark(m, compare) == compare;
   648 }
   650 // Note that the forwardee is not the same thing as the displaced_mark.
   651 // The forwardee is used when copying during scavenge and mark-sweep.
   652 // It does need to clear the low two locking- and GC-related bits.
   653 inline oop oopDesc::forwardee() const {
   654   return (oop) mark()->decode_pointer();
   655 }
   657 inline bool oopDesc::has_displaced_mark() const {
   658   return mark()->has_displaced_mark_helper();
   659 }
   661 inline markOop oopDesc::displaced_mark() const {
   662   return mark()->displaced_mark_helper();
   663 }
   665 inline void oopDesc::set_displaced_mark(markOop m) {
   666   mark()->set_displaced_mark_helper(m);
   667 }
   669 // The following method needs to be MT safe.
   670 inline uint oopDesc::age() const {
   671   assert(!is_forwarded(), "Attempt to read age from forwarded mark");
   672   if (has_displaced_mark()) {
   673     return displaced_mark()->age();
   674   } else {
   675     return mark()->age();
   676   }
   677 }
   679 inline void oopDesc::incr_age() {
   680   assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
   681   if (has_displaced_mark()) {
   682     set_displaced_mark(displaced_mark()->incr_age());
   683   } else {
   684     set_mark(mark()->incr_age());
   685   }
   686 }
   689 inline intptr_t oopDesc::identity_hash() {
   690   // Fast case; if the object is unlocked and the hash value is set, no locking is needed
   691   // Note: The mark must be read into local variable to avoid concurrent updates.
   692   markOop mrk = mark();
   693   if (mrk->is_unlocked() && !mrk->has_no_hash()) {
   694     return mrk->hash();
   695   } else if (mrk->is_marked()) {
   696     return mrk->hash();
   697   } else {
   698     return slow_identity_hash();
   699   }
   700 }
   702 inline int oopDesc::adjust_pointers() {
   703   debug_only(int check_size = size());
   704   int s = klass()->oop_adjust_pointers(this);
   705   assert(s == check_size, "should be the same");
   706   return s;
   707 }
   709 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix)                        \
   710                                                                            \
   711 inline int oopDesc::oop_iterate(OopClosureType* blk) {                     \
   712   SpecializationStats::record_call();                                      \
   713   return klass()->oop_oop_iterate##nv_suffix(this, blk);               \
   714 }                                                                          \
   715                                                                            \
   716 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) {       \
   717   SpecializationStats::record_call();                                      \
   718   return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr);       \
   719 }
   722 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
   723   // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
   724   // the do_oop calls, but turns off all other features in ExtendedOopClosure.
   725   NoHeaderExtendedOopClosure cl(blk);
   726   return oop_iterate(&cl);
   727 }
   729 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
   730   NoHeaderExtendedOopClosure cl(blk);
   731   return oop_iterate(&cl, mr);
   732 }
   734 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
   735 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
   737 #if INCLUDE_ALL_GCS
   738 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix)              \
   739                                                                            \
   740 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) {           \
   741   SpecializationStats::record_call();                                      \
   742   return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk);     \
   743 }
   745 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
   746 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
   747 #endif // INCLUDE_ALL_GCS
   749 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP

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