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

Tue, 24 Jun 2008 16:00:14 -0700

author
never
date
Tue, 24 Jun 2008 16:00:14 -0700
changeset 657
2a1a77d3458f
parent 602
feeb96a45707
child 631
d1605aabd0a1
child 779
6aae2f9d0294
permissions
-rw-r--r--

6718676: putback for 6604014 is incomplete
Reviewed-by: kvn, jrose

     1 /*
     2  * Copyright 1997-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
    21  * have any questions.
    22  *
    23  */
    25 // Implementation of all inlined member functions defined in oop.hpp
    26 // We need a separate file to avoid circular references
    28 inline void oopDesc::release_set_mark(markOop m) {
    29   OrderAccess::release_store_ptr(&_mark, m);
    30 }
    32 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
    33   return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
    34 }
    36 inline klassOop oopDesc::klass() const {
    37   if (UseCompressedOops) {
    38     return (klassOop)decode_heap_oop_not_null(_metadata._compressed_klass);
    39   } else {
    40     return _metadata._klass;
    41   }
    42 }
    44 inline klassOop oopDesc::klass_or_null() const volatile {
    45   // can be NULL in CMS
    46   if (UseCompressedOops) {
    47     return (klassOop)decode_heap_oop(_metadata._compressed_klass);
    48   } else {
    49     return _metadata._klass;
    50   }
    51 }
    53 inline int oopDesc::klass_gap_offset_in_bytes() {
    54   assert(UseCompressedOops, "only applicable to compressed headers");
    55   return oopDesc::klass_offset_in_bytes() + sizeof(narrowOop);
    56 }
    58 inline oop* oopDesc::klass_addr() {
    59   // Only used internally and with CMS and will not work with
    60   // UseCompressedOops
    61   assert(!UseCompressedOops, "only supported with uncompressed oops");
    62   return (oop*) &_metadata._klass;
    63 }
    65 inline narrowOop* oopDesc::compressed_klass_addr() {
    66   assert(UseCompressedOops, "only called by compressed oops");
    67   return (narrowOop*) &_metadata._compressed_klass;
    68 }
    70 inline void oopDesc::set_klass(klassOop k) {
    71   // since klasses are promoted no store check is needed
    72   assert(Universe::is_bootstrapping() || k != NULL, "must be a real klassOop");
    73   assert(Universe::is_bootstrapping() || k->is_klass(), "not a klassOop");
    74   if (UseCompressedOops) {
    75     oop_store_without_check(compressed_klass_addr(), (oop)k);
    76   } else {
    77     oop_store_without_check(klass_addr(), (oop) k);
    78   }
    79 }
    81 inline int oopDesc::klass_gap() const {
    82   return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
    83 }
    85 inline void oopDesc::set_klass_gap(int v) {
    86   if (UseCompressedOops) {
    87     *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
    88   }
    89 }
    91 inline void oopDesc::set_klass_to_list_ptr(oop k) {
    92   // This is only to be used during GC, for from-space objects, so no
    93   // barrier is needed.
    94   if (UseCompressedOops) {
    95     _metadata._compressed_klass = encode_heap_oop_not_null(k);
    96   } else {
    97     _metadata._klass = (klassOop)k;
    98   }
    99 }
   101 inline void   oopDesc::init_mark()                 { set_mark(markOopDesc::prototype_for_object(this)); }
   102 inline Klass* oopDesc::blueprint()           const { return klass()->klass_part(); }
   104 inline bool oopDesc::is_a(klassOop k)        const { return blueprint()->is_subtype_of(k); }
   106 inline bool oopDesc::is_instance()           const { return blueprint()->oop_is_instance(); }
   107 inline bool oopDesc::is_instanceRef()        const { return blueprint()->oop_is_instanceRef(); }
   108 inline bool oopDesc::is_array()              const { return blueprint()->oop_is_array(); }
   109 inline bool oopDesc::is_objArray()           const { return blueprint()->oop_is_objArray(); }
   110 inline bool oopDesc::is_typeArray()          const { return blueprint()->oop_is_typeArray(); }
   111 inline bool oopDesc::is_javaArray()          const { return blueprint()->oop_is_javaArray(); }
   112 inline bool oopDesc::is_symbol()             const { return blueprint()->oop_is_symbol(); }
   113 inline bool oopDesc::is_klass()              const { return blueprint()->oop_is_klass(); }
   114 inline bool oopDesc::is_thread()             const { return blueprint()->oop_is_thread(); }
   115 inline bool oopDesc::is_method()             const { return blueprint()->oop_is_method(); }
   116 inline bool oopDesc::is_constMethod()        const { return blueprint()->oop_is_constMethod(); }
   117 inline bool oopDesc::is_methodData()         const { return blueprint()->oop_is_methodData(); }
   118 inline bool oopDesc::is_constantPool()       const { return blueprint()->oop_is_constantPool(); }
   119 inline bool oopDesc::is_constantPoolCache()  const { return blueprint()->oop_is_constantPoolCache(); }
   120 inline bool oopDesc::is_compiledICHolder()   const { return blueprint()->oop_is_compiledICHolder(); }
   122 inline void*     oopDesc::field_base(int offset)        const { return (void*)&((char*)this)[offset]; }
   124 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
   125 inline jbyte*    oopDesc::byte_field_addr(int offset)   const { return (jbyte*)   field_base(offset); }
   126 inline jchar*    oopDesc::char_field_addr(int offset)   const { return (jchar*)   field_base(offset); }
   127 inline jboolean* oopDesc::bool_field_addr(int offset)   const { return (jboolean*)field_base(offset); }
   128 inline jint*     oopDesc::int_field_addr(int offset)    const { return (jint*)    field_base(offset); }
   129 inline jshort*   oopDesc::short_field_addr(int offset)  const { return (jshort*)  field_base(offset); }
   130 inline jlong*    oopDesc::long_field_addr(int offset)   const { return (jlong*)   field_base(offset); }
   131 inline jfloat*   oopDesc::float_field_addr(int offset)  const { return (jfloat*)  field_base(offset); }
   132 inline jdouble*  oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
   133 inline address*  oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
   136 // Functions for getting and setting oops within instance objects.
   137 // If the oops are compressed, the type passed to these overloaded functions
   138 // is narrowOop.  All functions are overloaded so they can be called by
   139 // template functions without conditionals (the compiler instantiates via
   140 // the right type and inlines the appopriate code).
   142 inline bool oopDesc::is_null(oop obj)       { return obj == NULL; }
   143 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
   145 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
   146 // offset from the heap base.  Saving the check for null can save instructions
   147 // in inner GC loops so these are separated.
   149 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
   150   assert(!is_null(v), "oop value can never be zero");
   151   address heap_base = Universe::heap_base();
   152   uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)heap_base, 1));
   153   assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
   154   uint64_t result = pd >> LogMinObjAlignmentInBytes;
   155   assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
   156   return (narrowOop)result;
   157 }
   159 inline narrowOop oopDesc::encode_heap_oop(oop v) {
   160   return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
   161 }
   163 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
   164   assert(!is_null(v), "narrow oop value can never be zero");
   165   address heap_base = Universe::heap_base();
   166   return (oop)(void*)((uintptr_t)heap_base + ((uintptr_t)v << LogMinObjAlignmentInBytes));
   167 }
   169 inline oop oopDesc::decode_heap_oop(narrowOop v) {
   170   return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
   171 }
   173 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
   174 inline oop oopDesc::decode_heap_oop(oop v)  { return v; }
   176 // Load an oop out of the Java heap as is without decoding.
   177 // Called by GC to check for null before decoding.
   178 inline oop       oopDesc::load_heap_oop(oop* p)          { return *p; }
   179 inline narrowOop oopDesc::load_heap_oop(narrowOop* p)    { return *p; }
   181 // Load and decode an oop out of the Java heap into a wide oop.
   182 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p)       { return *p; }
   183 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
   184   return decode_heap_oop_not_null(*p);
   185 }
   187 // Load and decode an oop out of the heap accepting null
   188 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
   189 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
   190   return decode_heap_oop(*p);
   191 }
   193 // Store already encoded heap oop into the heap.
   194 inline void oopDesc::store_heap_oop(oop* p, oop v)                 { *p = v; }
   195 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v)     { *p = v; }
   197 // Encode and store a heap oop.
   198 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
   199   *p = encode_heap_oop_not_null(v);
   200 }
   201 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
   203 // Encode and store a heap oop allowing for null.
   204 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
   205   *p = encode_heap_oop(v);
   206 }
   207 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
   209 // Store heap oop as is for volatile fields.
   210 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
   211   OrderAccess::release_store_ptr(p, v);
   212 }
   213 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
   214                                             narrowOop v) {
   215   OrderAccess::release_store(p, v);
   216 }
   218 inline void oopDesc::release_encode_store_heap_oop_not_null(
   219                                                 volatile narrowOop* p, oop v) {
   220   // heap oop is not pointer sized.
   221   OrderAccess::release_store(p, encode_heap_oop_not_null(v));
   222 }
   224 inline void oopDesc::release_encode_store_heap_oop_not_null(
   225                                                       volatile oop* p, oop v) {
   226   OrderAccess::release_store_ptr(p, v);
   227 }
   229 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
   230                                                            oop v) {
   231   OrderAccess::release_store_ptr(p, v);
   232 }
   233 inline void oopDesc::release_encode_store_heap_oop(
   234                                                 volatile narrowOop* p, oop v) {
   235   OrderAccess::release_store(p, encode_heap_oop(v));
   236 }
   239 // These functions are only used to exchange oop fields in instances,
   240 // not headers.
   241 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
   242   if (UseCompressedOops) {
   243     // encode exchange value from oop to T
   244     narrowOop val = encode_heap_oop(exchange_value);
   245     narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
   246     // decode old from T to oop
   247     return decode_heap_oop(old);
   248   } else {
   249     return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
   250   }
   251 }
   253 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
   254                                                 volatile HeapWord *dest,
   255                                                 oop compare_value) {
   256   if (UseCompressedOops) {
   257     // encode exchange and compare value from oop to T
   258     narrowOop val = encode_heap_oop(exchange_value);
   259     narrowOop cmp = encode_heap_oop(compare_value);
   261     narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
   262     // decode old from T to oop
   263     return decode_heap_oop(old);
   264   } else {
   265     return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
   266   }
   267 }
   269 // In order to put or get a field out of an instance, must first check
   270 // if the field has been compressed and uncompress it.
   271 inline oop oopDesc::obj_field(int offset) const {
   272   return UseCompressedOops ?
   273     load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
   274     load_decode_heap_oop(obj_field_addr<oop>(offset));
   275 }
   276 inline void oopDesc::obj_field_put(int offset, oop value) {
   277   UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
   278                       oop_store(obj_field_addr<oop>(offset),       value);
   279 }
   280 inline void oopDesc::obj_field_raw_put(int offset, oop value) {
   281   UseCompressedOops ?
   282     encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
   283     encode_store_heap_oop(obj_field_addr<oop>(offset),       value);
   284 }
   286 inline jbyte oopDesc::byte_field(int offset) const                  { return (jbyte) *byte_field_addr(offset);    }
   287 inline void oopDesc::byte_field_put(int offset, jbyte contents)     { *byte_field_addr(offset) = (jint) contents; }
   289 inline jboolean oopDesc::bool_field(int offset) const               { return (jboolean) *bool_field_addr(offset); }
   290 inline void oopDesc::bool_field_put(int offset, jboolean contents)  { *bool_field_addr(offset) = (jint) contents; }
   292 inline jchar oopDesc::char_field(int offset) const                  { return (jchar) *char_field_addr(offset);    }
   293 inline void oopDesc::char_field_put(int offset, jchar contents)     { *char_field_addr(offset) = (jint) contents; }
   295 inline jint oopDesc::int_field(int offset) const                    { return *int_field_addr(offset);        }
   296 inline void oopDesc::int_field_put(int offset, jint contents)       { *int_field_addr(offset) = contents;    }
   298 inline jshort oopDesc::short_field(int offset) const                { return (jshort) *short_field_addr(offset);  }
   299 inline void oopDesc::short_field_put(int offset, jshort contents)   { *short_field_addr(offset) = (jint) contents;}
   301 inline jlong oopDesc::long_field(int offset) const                  { return *long_field_addr(offset);       }
   302 inline void oopDesc::long_field_put(int offset, jlong contents)     { *long_field_addr(offset) = contents;   }
   304 inline jfloat oopDesc::float_field(int offset) const                { return *float_field_addr(offset);      }
   305 inline void oopDesc::float_field_put(int offset, jfloat contents)   { *float_field_addr(offset) = contents;  }
   307 inline jdouble oopDesc::double_field(int offset) const              { return *double_field_addr(offset);     }
   308 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
   310 inline address oopDesc::address_field(int offset) const              { return *address_field_addr(offset);     }
   311 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
   313 inline oop oopDesc::obj_field_acquire(int offset) const {
   314   return UseCompressedOops ?
   315              decode_heap_oop((narrowOop)
   316                OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
   317            : decode_heap_oop((oop)
   318                OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
   319 }
   320 inline void oopDesc::release_obj_field_put(int offset, oop value) {
   321   UseCompressedOops ?
   322     oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
   323     oop_store((volatile oop*)      obj_field_addr<oop>(offset),       value);
   324 }
   326 inline jbyte oopDesc::byte_field_acquire(int offset) const                  { return OrderAccess::load_acquire(byte_field_addr(offset));     }
   327 inline void oopDesc::release_byte_field_put(int offset, jbyte contents)     { OrderAccess::release_store(byte_field_addr(offset), contents); }
   329 inline jboolean oopDesc::bool_field_acquire(int offset) const               { return OrderAccess::load_acquire(bool_field_addr(offset));     }
   330 inline void oopDesc::release_bool_field_put(int offset, jboolean contents)  { OrderAccess::release_store(bool_field_addr(offset), contents); }
   332 inline jchar oopDesc::char_field_acquire(int offset) const                  { return OrderAccess::load_acquire(char_field_addr(offset));     }
   333 inline void oopDesc::release_char_field_put(int offset, jchar contents)     { OrderAccess::release_store(char_field_addr(offset), contents); }
   335 inline jint oopDesc::int_field_acquire(int offset) const                    { return OrderAccess::load_acquire(int_field_addr(offset));      }
   336 inline void oopDesc::release_int_field_put(int offset, jint contents)       { OrderAccess::release_store(int_field_addr(offset), contents);  }
   338 inline jshort oopDesc::short_field_acquire(int offset) const                { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
   339 inline void oopDesc::release_short_field_put(int offset, jshort contents)   { OrderAccess::release_store(short_field_addr(offset), contents);     }
   341 inline jlong oopDesc::long_field_acquire(int offset) const                  { return OrderAccess::load_acquire(long_field_addr(offset));       }
   342 inline void oopDesc::release_long_field_put(int offset, jlong contents)     { OrderAccess::release_store(long_field_addr(offset), contents);   }
   344 inline jfloat oopDesc::float_field_acquire(int offset) const                { return OrderAccess::load_acquire(float_field_addr(offset));      }
   345 inline void oopDesc::release_float_field_put(int offset, jfloat contents)   { OrderAccess::release_store(float_field_addr(offset), contents);  }
   347 inline jdouble oopDesc::double_field_acquire(int offset) const              { return OrderAccess::load_acquire(double_field_addr(offset));     }
   348 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
   350 inline int oopDesc::size_given_klass(Klass* klass)  {
   351   int lh = klass->layout_helper();
   352   int s  = lh >> LogHeapWordSize;  // deliver size scaled by wordSize
   354   // lh is now a value computed at class initialization that may hint
   355   // at the size.  For instances, this is positive and equal to the
   356   // size.  For arrays, this is negative and provides log2 of the
   357   // array element size.  For other oops, it is zero and thus requires
   358   // a virtual call.
   359   //
   360   // We go to all this trouble because the size computation is at the
   361   // heart of phase 2 of mark-compaction, and called for every object,
   362   // alive or dead.  So the speed here is equal in importance to the
   363   // speed of allocation.
   365   if (lh <= Klass::_lh_neutral_value) {
   366     // The most common case is instances; fall through if so.
   367     if (lh < Klass::_lh_neutral_value) {
   368       // Second most common case is arrays.  We have to fetch the
   369       // length of the array, shift (multiply) it appropriately,
   370       // up to wordSize, add the header, and align to object size.
   371       size_t size_in_bytes;
   372 #ifdef _M_IA64
   373       // The Windows Itanium Aug 2002 SDK hoists this load above
   374       // the check for s < 0.  An oop at the end of the heap will
   375       // cause an access violation if this load is performed on a non
   376       // array oop.  Making the reference volatile prohibits this.
   377       // (%%% please explain by what magic the length is actually fetched!)
   378       volatile int *array_length;
   379       array_length = (volatile int *)( (intptr_t)this +
   380                           arrayOopDesc::length_offset_in_bytes() );
   381       assert(array_length > 0, "Integer arithmetic problem somewhere");
   382       // Put into size_t to avoid overflow.
   383       size_in_bytes = (size_t) array_length;
   384       size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
   385 #else
   386       size_t array_length = (size_t) ((arrayOop)this)->length();
   387       size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
   388 #endif
   389       size_in_bytes += Klass::layout_helper_header_size(lh);
   391       // This code could be simplified, but by keeping array_header_in_bytes
   392       // in units of bytes and doing it this way we can round up just once,
   393       // skipping the intermediate round to HeapWordSize.  Cast the result
   394       // of round_to to size_t to guarantee unsigned division == right shift.
   395       s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
   396         HeapWordSize);
   398       // UseParNewGC can change the length field of an "old copy" of an object
   399       // array in the young gen so it indicates the stealable portion of
   400       // an already copied array. This will cause the first disjunct below
   401       // to fail if the sizes are computed across such a concurrent change.
   402       // UseParNewGC also runs with promotion labs (which look like int
   403       // filler arrays) which are subject to changing their declared size
   404       // when finally retiring a PLAB; this also can cause the first disjunct
   405       // to fail for another worker thread that is concurrently walking the block
   406       // offset table. Both these invariant failures are benign for their
   407       // current uses; we relax the assertion checking to cover these two cases below:
   408       //     is_objArray() && is_forwarded()   // covers first scenario above
   409       //  || is_typeArray()                    // covers second scenario above
   410       // If and when UseParallelGC uses the same obj array oop stealing/chunking
   411       // technique, or when G1 is integrated (and currently uses this array chunking
   412       // technique) we will need to suitably modify the assertion.
   413       assert((s == klass->oop_size(this)) ||
   414              (((UseParNewGC || UseParallelGC) &&
   415               Universe::heap()->is_gc_active()) &&
   416               (is_typeArray() ||
   417                (is_objArray() && is_forwarded()))),
   418              "wrong array object size");
   419     } else {
   420       // Must be zero, so bite the bullet and take the virtual call.
   421       s = klass->oop_size(this);
   422     }
   423   }
   425   assert(s % MinObjAlignment == 0, "alignment check");
   426   assert(s > 0, "Bad size calculated");
   427   return s;
   428 }
   431 inline int oopDesc::size()  {
   432   return size_given_klass(blueprint());
   433 }
   435 inline bool oopDesc::is_parsable() {
   436   return blueprint()->oop_is_parsable(this);
   437 }
   439 inline void update_barrier_set(void* p, oop v) {
   440   assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
   441   oopDesc::bs()->write_ref_field(p, v);
   442 }
   444 template <class T> inline void oop_store(T* p, oop v) {
   445   if (always_do_update_barrier) {
   446     oop_store((volatile T*)p, v);
   447   } else {
   448     oopDesc::encode_store_heap_oop(p, v);
   449     update_barrier_set(p, v);
   450   }
   451 }
   453 template <class T> inline void oop_store(volatile T* p, oop v) {
   454   // Used by release_obj_field_put, so use release_store_ptr.
   455   oopDesc::release_encode_store_heap_oop(p, v);
   456   update_barrier_set((void*)p, v);
   457 }
   459 template <class T> inline void oop_store_without_check(T* p, oop v) {
   460   // XXX YSR FIX ME!!!
   461   if (always_do_update_barrier) {
   462     oop_store(p, v);
   463   } else {
   464     assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier(p, v),
   465            "oop store without store check failed");
   466     oopDesc::encode_store_heap_oop(p, v);
   467   }
   468 }
   470 // When it absolutely has to get there.
   471 template <class T> inline void oop_store_without_check(volatile T* p, oop v) {
   472   // XXX YSR FIX ME!!!
   473   if (always_do_update_barrier) {
   474     oop_store(p, v);
   475   } else {
   476     assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier((T*)p, v),
   477            "oop store without store check failed");
   478     oopDesc::release_encode_store_heap_oop(p, v);
   479   }
   480 }
   482 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
   483 // (without having to remember the function name this calls).
   484 inline void oop_store_raw(HeapWord* addr, oop value) {
   485   if (UseCompressedOops) {
   486     oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
   487   } else {
   488     oopDesc::encode_store_heap_oop((oop*)addr, value);
   489   }
   490 }
   492 // Used only for markSweep, scavenging
   493 inline bool oopDesc::is_gc_marked() const {
   494   return mark()->is_marked();
   495 }
   497 inline bool oopDesc::is_locked() const {
   498   return mark()->is_locked();
   499 }
   501 inline bool oopDesc::is_unlocked() const {
   502   return mark()->is_unlocked();
   503 }
   505 inline bool oopDesc::has_bias_pattern() const {
   506   return mark()->has_bias_pattern();
   507 }
   509 inline bool check_obj_alignment(oop obj) {
   510   return (intptr_t)obj % MinObjAlignmentInBytes == 0;
   511 }
   514 // used only for asserts
   515 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
   516   oop obj = (oop) this;
   517   if (!check_obj_alignment(obj)) return false;
   518   if (!Universe::heap()->is_in_reserved(obj)) return false;
   519   // obj is aligned and accessible in heap
   520   // try to find metaclass cycle safely without seg faulting on bad input
   521   // we should reach klassKlassObj by following klass link at most 3 times
   522   for (int i = 0; i < 3; i++) {
   523     obj = obj->klass_or_null();
   524     // klass should be aligned and in permspace
   525     if (!check_obj_alignment(obj)) return false;
   526     if (!Universe::heap()->is_in_permanent(obj)) return false;
   527   }
   528   if (obj != Universe::klassKlassObj()) {
   529     // During a dump, the _klassKlassObj moved to a shared space.
   530     if (DumpSharedSpaces && Universe::klassKlassObj()->is_shared()) {
   531       return true;
   532     }
   533     return false;
   534   }
   536   // Header verification: the mark is typically non-NULL. If we're
   537   // at a safepoint, it must not be null.
   538   // Outside of a safepoint, the header could be changing (for example,
   539   // another thread could be inflating a lock on this object).
   540   if (ignore_mark_word) {
   541     return true;
   542   }
   543   if (mark() != NULL) {
   544     return true;
   545   }
   546   return !SafepointSynchronize::is_at_safepoint();
   547 }
   550 // used only for asserts
   551 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
   552   return this == NULL ? true : is_oop(ignore_mark_word);
   553 }
   555 #ifndef PRODUCT
   556 // used only for asserts
   557 inline bool oopDesc::is_unlocked_oop() const {
   558   if (!Universe::heap()->is_in_reserved(this)) return false;
   559   return mark()->is_unlocked();
   560 }
   561 #endif // PRODUCT
   563 inline void oopDesc::follow_header() {
   564   if (UseCompressedOops) {
   565     MarkSweep::mark_and_push(compressed_klass_addr());
   566   } else {
   567     MarkSweep::mark_and_push(klass_addr());
   568   }
   569 }
   571 inline void oopDesc::follow_contents(void) {
   572   assert (is_gc_marked(), "should be marked");
   573   blueprint()->oop_follow_contents(this);
   574 }
   577 // Used by scavengers
   579 inline bool oopDesc::is_forwarded() const {
   580   // The extra heap check is needed since the obj might be locked, in which case the
   581   // mark would point to a stack location and have the sentinel bit cleared
   582   return mark()->is_marked();
   583 }
   585 // Used by scavengers
   586 inline void oopDesc::forward_to(oop p) {
   587   assert(Universe::heap()->is_in_reserved(p),
   588          "forwarding to something not in heap");
   589   markOop m = markOopDesc::encode_pointer_as_mark(p);
   590   assert(m->decode_pointer() == p, "encoding must be reversable");
   591   set_mark(m);
   592 }
   594 // Used by parallel scavengers
   595 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
   596   assert(Universe::heap()->is_in_reserved(p),
   597          "forwarding to something not in heap");
   598   markOop m = markOopDesc::encode_pointer_as_mark(p);
   599   assert(m->decode_pointer() == p, "encoding must be reversable");
   600   return cas_set_mark(m, compare) == compare;
   601 }
   603 // Note that the forwardee is not the same thing as the displaced_mark.
   604 // The forwardee is used when copying during scavenge and mark-sweep.
   605 // It does need to clear the low two locking- and GC-related bits.
   606 inline oop oopDesc::forwardee() const {
   607   return (oop) mark()->decode_pointer();
   608 }
   610 inline bool oopDesc::has_displaced_mark() const {
   611   return mark()->has_displaced_mark_helper();
   612 }
   614 inline markOop oopDesc::displaced_mark() const {
   615   return mark()->displaced_mark_helper();
   616 }
   618 inline void oopDesc::set_displaced_mark(markOop m) {
   619   mark()->set_displaced_mark_helper(m);
   620 }
   622 // The following method needs to be MT safe.
   623 inline int oopDesc::age() const {
   624   assert(!is_forwarded(), "Attempt to read age from forwarded mark");
   625   if (has_displaced_mark()) {
   626     return displaced_mark()->age();
   627   } else {
   628     return mark()->age();
   629   }
   630 }
   632 inline void oopDesc::incr_age() {
   633   assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
   634   if (has_displaced_mark()) {
   635     set_displaced_mark(displaced_mark()->incr_age());
   636   } else {
   637     set_mark(mark()->incr_age());
   638   }
   639 }
   642 inline intptr_t oopDesc::identity_hash() {
   643   // Fast case; if the object is unlocked and the hash value is set, no locking is needed
   644   // Note: The mark must be read into local variable to avoid concurrent updates.
   645   markOop mrk = mark();
   646   if (mrk->is_unlocked() && !mrk->has_no_hash()) {
   647     return mrk->hash();
   648   } else if (mrk->is_marked()) {
   649     return mrk->hash();
   650   } else {
   651     return slow_identity_hash();
   652   }
   653 }
   655 inline void oopDesc::oop_iterate_header(OopClosure* blk) {
   656   if (UseCompressedOops) {
   657     blk->do_oop(compressed_klass_addr());
   658   } else {
   659     blk->do_oop(klass_addr());
   660   }
   661 }
   663 inline void oopDesc::oop_iterate_header(OopClosure* blk, MemRegion mr) {
   664   if (UseCompressedOops) {
   665     if (mr.contains(compressed_klass_addr())) {
   666       blk->do_oop(compressed_klass_addr());
   667     }
   668   } else {
   669     if (mr.contains(klass_addr())) blk->do_oop(klass_addr());
   670   }
   671 }
   673 inline int oopDesc::adjust_pointers() {
   674   debug_only(int check_size = size());
   675   int s = blueprint()->oop_adjust_pointers(this);
   676   assert(s == check_size, "should be the same");
   677   return s;
   678 }
   680 inline void oopDesc::adjust_header() {
   681   if (UseCompressedOops) {
   682     MarkSweep::adjust_pointer(compressed_klass_addr());
   683   } else {
   684     MarkSweep::adjust_pointer(klass_addr());
   685   }
   686 }
   688 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix)                        \
   689                                                                            \
   690 inline int oopDesc::oop_iterate(OopClosureType* blk) {                     \
   691   SpecializationStats::record_call();                                      \
   692   return blueprint()->oop_oop_iterate##nv_suffix(this, blk);               \
   693 }                                                                          \
   694                                                                            \
   695 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) {       \
   696   SpecializationStats::record_call();                                      \
   697   return blueprint()->oop_oop_iterate##nv_suffix##_m(this, blk, mr);       \
   698 }
   700 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
   701 ALL_OOP_OOP_ITERATE_CLOSURES_3(OOP_ITERATE_DEFN)
   704 inline bool oopDesc::is_shared() const {
   705   return CompactingPermGenGen::is_shared(this);
   706 }
   708 inline bool oopDesc::is_shared_readonly() const {
   709   return CompactingPermGenGen::is_shared_readonly(this);
   710 }
   712 inline bool oopDesc::is_shared_readwrite() const {
   713   return CompactingPermGenGen::is_shared_readwrite(this);
   714 }

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