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

Sat, 07 Nov 2020 10:30:02 +0800

author
aoqi
date
Sat, 07 Nov 2020 10:30:02 +0800
changeset 10026
8c95980d0b66
parent 8604
04d83ba48607
permissions
-rw-r--r--

Added tag mips-jdk8u275-b01 for changeset d3b4d62f391f

     1 /*
     2  * Copyright (c) 1997, 2016, 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 /*
    26  * This file has been modified by Loongson Technology in 2015. These
    27  * modifications are Copyright (c) 2015 Loongson Technology, and are made
    28  * available on the same license terms set forth above.
    29  */
    31 #ifndef SHARE_VM_OOPS_OOP_INLINE_HPP
    32 #define SHARE_VM_OOPS_OOP_INLINE_HPP
    34 #include "gc_implementation/shared/ageTable.hpp"
    35 #include "gc_implementation/shared/markSweep.inline.hpp"
    36 #include "gc_interface/collectedHeap.inline.hpp"
    37 #include "memory/barrierSet.inline.hpp"
    38 #include "memory/cardTableModRefBS.hpp"
    39 #include "memory/genCollectedHeap.hpp"
    40 #include "memory/generation.hpp"
    41 #include "memory/specialized_oop_closures.hpp"
    42 #include "oops/arrayKlass.hpp"
    43 #include "oops/arrayOop.hpp"
    44 #include "oops/klass.inline.hpp"
    45 #include "oops/markOop.inline.hpp"
    46 #include "oops/oop.hpp"
    47 #include "runtime/atomic.inline.hpp"
    48 #include "runtime/orderAccess.inline.hpp"
    49 #include "runtime/os.hpp"
    50 #include "utilities/macros.hpp"
    51 #ifdef TARGET_ARCH_x86
    52 # include "bytes_x86.hpp"
    53 #endif
    54 #ifdef TARGET_ARCH_sparc
    55 # include "bytes_sparc.hpp"
    56 #endif
    57 #ifdef TARGET_ARCH_zero
    58 # include "bytes_zero.hpp"
    59 #endif
    60 #ifdef TARGET_ARCH_arm
    61 # include "bytes_arm.hpp"
    62 #endif
    63 #ifdef TARGET_ARCH_ppc
    64 # include "bytes_ppc.hpp"
    65 #endif
    66 #ifdef TARGET_ARCH_mips
    67 # include "bytes_mips.hpp"
    68 #endif
    70 // Implementation of all inlined member functions defined in oop.hpp
    71 // We need a separate file to avoid circular references
    73 inline void oopDesc::release_set_mark(markOop m) {
    74   OrderAccess::release_store_ptr(&_mark, m);
    75 }
    77 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
    78   return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
    79 }
    81 inline Klass* oopDesc::klass() const {
    82   if (UseCompressedClassPointers) {
    83     return Klass::decode_klass_not_null(_metadata._compressed_klass);
    84   } else {
    85     return _metadata._klass;
    86   }
    87 }
    89 inline Klass* oopDesc::klass_or_null() const volatile {
    90   // can be NULL in CMS
    91   if (UseCompressedClassPointers) {
    92     return Klass::decode_klass(_metadata._compressed_klass);
    93   } else {
    94     return _metadata._klass;
    95   }
    96 }
    98 inline int oopDesc::klass_gap_offset_in_bytes() {
    99   assert(UseCompressedClassPointers, "only applicable to compressed klass pointers");
   100   return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass);
   101 }
   103 inline Klass** oopDesc::klass_addr() {
   104   // Only used internally and with CMS and will not work with
   105   // UseCompressedOops
   106   assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
   107   return (Klass**) &_metadata._klass;
   108 }
   110 inline narrowKlass* oopDesc::compressed_klass_addr() {
   111   assert(UseCompressedClassPointers, "only called by compressed klass pointers");
   112   return &_metadata._compressed_klass;
   113 }
   115 inline void oopDesc::set_klass(Klass* k) {
   116   // since klasses are promoted no store check is needed
   117   assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*");
   118   assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*");
   119   if (UseCompressedClassPointers) {
   120     *compressed_klass_addr() = Klass::encode_klass_not_null(k);
   121   } else {
   122     *klass_addr() = k;
   123   }
   124 }
   126 inline int oopDesc::klass_gap() const {
   127   return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
   128 }
   130 inline void oopDesc::set_klass_gap(int v) {
   131   if (UseCompressedClassPointers) {
   132     *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
   133   }
   134 }
   136 inline void oopDesc::set_klass_to_list_ptr(oop k) {
   137   // This is only to be used during GC, for from-space objects, so no
   138   // barrier is needed.
   139   if (UseCompressedClassPointers) {
   140     _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k);  // may be null (parnew overflow handling)
   141   } else {
   142     _metadata._klass = (Klass*)(address)k;
   143   }
   144 }
   146 inline oop oopDesc::list_ptr_from_klass() {
   147   // This is only to be used during GC, for from-space objects.
   148   if (UseCompressedClassPointers) {
   149     return decode_heap_oop((narrowOop)_metadata._compressed_klass);
   150   } else {
   151     // Special case for GC
   152     return (oop)(address)_metadata._klass;
   153   }
   154 }
   156 inline void   oopDesc::init_mark()                 { set_mark(markOopDesc::prototype_for_object(this)); }
   158 inline bool oopDesc::is_a(Klass* k)        const { return klass()->is_subtype_of(k); }
   160 inline bool oopDesc::is_instance()            const { return klass()->oop_is_instance(); }
   161 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); }
   162 inline bool oopDesc::is_instanceMirror()      const { return klass()->oop_is_instanceMirror(); }
   163 inline bool oopDesc::is_instanceRef()         const { return klass()->oop_is_instanceRef(); }
   164 inline bool oopDesc::is_array()               const { return klass()->oop_is_array(); }
   165 inline bool oopDesc::is_objArray()            const { return klass()->oop_is_objArray(); }
   166 inline bool oopDesc::is_typeArray()           const { return klass()->oop_is_typeArray(); }
   168 inline void*     oopDesc::field_base(int offset)        const { return (void*)&((char*)this)[offset]; }
   170 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
   171 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
   172 inline jbyte*    oopDesc::byte_field_addr(int offset)   const { return (jbyte*)   field_base(offset); }
   173 inline jchar*    oopDesc::char_field_addr(int offset)   const { return (jchar*)   field_base(offset); }
   174 inline jboolean* oopDesc::bool_field_addr(int offset)   const { return (jboolean*)field_base(offset); }
   175 inline jint*     oopDesc::int_field_addr(int offset)    const { return (jint*)    field_base(offset); }
   176 inline jshort*   oopDesc::short_field_addr(int offset)  const { return (jshort*)  field_base(offset); }
   177 inline jlong*    oopDesc::long_field_addr(int offset)   const { return (jlong*)   field_base(offset); }
   178 inline jfloat*   oopDesc::float_field_addr(int offset)  const { return (jfloat*)  field_base(offset); }
   179 inline jdouble*  oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
   180 inline address*  oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
   183 // Functions for getting and setting oops within instance objects.
   184 // If the oops are compressed, the type passed to these overloaded functions
   185 // is narrowOop.  All functions are overloaded so they can be called by
   186 // template functions without conditionals (the compiler instantiates via
   187 // the right type and inlines the appopriate code).
   189 inline bool oopDesc::is_null(oop obj)       { return obj == NULL; }
   190 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
   192 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
   193 // offset from the heap base.  Saving the check for null can save instructions
   194 // in inner GC loops so these are separated.
   196 inline bool check_obj_alignment(oop obj) {
   197   return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
   198 }
   200 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
   201   assert(!is_null(v), "oop value can never be zero");
   202   assert(check_obj_alignment(v), "Address not aligned");
   203   assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
   204   address base = Universe::narrow_oop_base();
   205   int    shift = Universe::narrow_oop_shift();
   206   uint64_t  pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
   207   assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
   208   uint64_t result = pd >> shift;
   209   assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
   210   assert(decode_heap_oop(result) == v, "reversibility");
   211   return (narrowOop)result;
   212 }
   214 inline narrowOop oopDesc::encode_heap_oop(oop v) {
   215   return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
   216 }
   218 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
   219   assert(!is_null(v), "narrow oop value can never be zero");
   220   address base = Universe::narrow_oop_base();
   221   int    shift = Universe::narrow_oop_shift();
   222   oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
   223   assert(check_obj_alignment(result), err_msg("address not aligned: " INTPTR_FORMAT, p2i((void*) result)));
   224   return result;
   225 }
   227 inline oop oopDesc::decode_heap_oop(narrowOop v) {
   228   return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
   229 }
   231 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
   232 inline oop oopDesc::decode_heap_oop(oop v)  { return v; }
   234 // Load an oop out of the Java heap as is without decoding.
   235 // Called by GC to check for null before decoding.
   236 inline oop       oopDesc::load_heap_oop(oop* p)          { return *p; }
   237 inline narrowOop oopDesc::load_heap_oop(narrowOop* p)    { return *p; }
   239 // Load and decode an oop out of the Java heap into a wide oop.
   240 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p)       { return *p; }
   241 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
   242   return decode_heap_oop_not_null(*p);
   243 }
   245 // Load and decode an oop out of the heap accepting null
   246 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
   247 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
   248   return decode_heap_oop(*p);
   249 }
   251 // Store already encoded heap oop into the heap.
   252 inline void oopDesc::store_heap_oop(oop* p, oop v)                 { *p = v; }
   253 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v)     { *p = v; }
   255 // Encode and store a heap oop.
   256 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
   257   *p = encode_heap_oop_not_null(v);
   258 }
   259 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
   261 // Encode and store a heap oop allowing for null.
   262 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
   263   *p = encode_heap_oop(v);
   264 }
   265 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
   267 // Store heap oop as is for volatile fields.
   268 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
   269   OrderAccess::release_store_ptr(p, v);
   270 }
   271 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
   272                                             narrowOop v) {
   273   OrderAccess::release_store(p, v);
   274 }
   276 inline void oopDesc::release_encode_store_heap_oop_not_null(
   277                                                 volatile narrowOop* p, oop v) {
   278   // heap oop is not pointer sized.
   279   OrderAccess::release_store(p, encode_heap_oop_not_null(v));
   280 }
   282 inline void oopDesc::release_encode_store_heap_oop_not_null(
   283                                                       volatile oop* p, oop v) {
   284   OrderAccess::release_store_ptr(p, v);
   285 }
   287 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
   288                                                            oop v) {
   289   OrderAccess::release_store_ptr(p, v);
   290 }
   291 inline void oopDesc::release_encode_store_heap_oop(
   292                                                 volatile narrowOop* p, oop v) {
   293   OrderAccess::release_store(p, encode_heap_oop(v));
   294 }
   297 // These functions are only used to exchange oop fields in instances,
   298 // not headers.
   299 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
   300   if (UseCompressedOops) {
   301     // encode exchange value from oop to T
   302     narrowOop val = encode_heap_oop(exchange_value);
   303     narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
   304     // decode old from T to oop
   305     return decode_heap_oop(old);
   306   } else {
   307     return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
   308   }
   309 }
   311 // In order to put or get a field out of an instance, must first check
   312 // if the field has been compressed and uncompress it.
   313 inline oop oopDesc::obj_field(int offset) const {
   314   return UseCompressedOops ?
   315     load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
   316     load_decode_heap_oop(obj_field_addr<oop>(offset));
   317 }
   318 inline volatile oop oopDesc::obj_field_volatile(int offset) const {
   319   volatile oop value = obj_field(offset);
   320   OrderAccess::acquire();
   321   return value;
   322 }
   323 inline void oopDesc::obj_field_put(int offset, oop value) {
   324   UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
   325                       oop_store(obj_field_addr<oop>(offset),       value);
   326 }
   328 inline Metadata* oopDesc::metadata_field(int offset) const {
   329   return *metadata_field_addr(offset);
   330 }
   332 inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
   333   *metadata_field_addr(offset) = value;
   334 }
   336 inline void oopDesc::obj_field_put_raw(int offset, oop value) {
   337   UseCompressedOops ?
   338     encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
   339     encode_store_heap_oop(obj_field_addr<oop>(offset),       value);
   340 }
   341 inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
   342   OrderAccess::release();
   343   obj_field_put(offset, value);
   344   OrderAccess::fence();
   345 }
   347 inline jbyte oopDesc::byte_field(int offset) const                  { return (jbyte) *byte_field_addr(offset);    }
   348 inline void oopDesc::byte_field_put(int offset, jbyte contents)     { *byte_field_addr(offset) = (jint) contents; }
   350 inline jboolean oopDesc::bool_field(int offset) const               { return (jboolean) *bool_field_addr(offset); }
   351 inline void oopDesc::bool_field_put(int offset, jboolean contents)  { *bool_field_addr(offset) = (( (jint) contents) & 1); }
   353 inline jchar oopDesc::char_field(int offset) const                  { return (jchar) *char_field_addr(offset);    }
   354 inline void oopDesc::char_field_put(int offset, jchar contents)     { *char_field_addr(offset) = (jint) contents; }
   356 inline jint oopDesc::int_field(int offset) const                    { return *int_field_addr(offset);        }
   357 inline void oopDesc::int_field_put(int offset, jint contents)       { *int_field_addr(offset) = contents;    }
   359 inline jshort oopDesc::short_field(int offset) const                { return (jshort) *short_field_addr(offset);  }
   360 inline void oopDesc::short_field_put(int offset, jshort contents)   { *short_field_addr(offset) = (jint) contents;}
   362 inline jlong oopDesc::long_field(int offset) const                  { return *long_field_addr(offset);       }
   363 inline void oopDesc::long_field_put(int offset, jlong contents)     { *long_field_addr(offset) = contents;   }
   365 inline jfloat oopDesc::float_field(int offset) const                { return *float_field_addr(offset);      }
   366 inline void oopDesc::float_field_put(int offset, jfloat contents)   { *float_field_addr(offset) = contents;  }
   368 inline jdouble oopDesc::double_field(int offset) const              { return *double_field_addr(offset);     }
   369 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
   371 inline address oopDesc::address_field(int offset) const              { return *address_field_addr(offset);     }
   372 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
   374 inline oop oopDesc::obj_field_acquire(int offset) const {
   375   return UseCompressedOops ?
   376              decode_heap_oop((narrowOop)
   377                OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
   378            : decode_heap_oop((oop)
   379                OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
   380 }
   381 inline void oopDesc::release_obj_field_put(int offset, oop value) {
   382   UseCompressedOops ?
   383     oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
   384     oop_store((volatile oop*)      obj_field_addr<oop>(offset),       value);
   385 }
   387 inline jbyte oopDesc::byte_field_acquire(int offset) const                  { return OrderAccess::load_acquire(byte_field_addr(offset));     }
   388 inline void oopDesc::release_byte_field_put(int offset, jbyte contents)     { OrderAccess::release_store(byte_field_addr(offset), contents); }
   390 inline jboolean oopDesc::bool_field_acquire(int offset) const               { return OrderAccess::load_acquire(bool_field_addr(offset));     }
   391 inline void oopDesc::release_bool_field_put(int offset, jboolean contents)  { OrderAccess::release_store(bool_field_addr(offset), (contents & 1)); }
   393 inline jchar oopDesc::char_field_acquire(int offset) const                  { return OrderAccess::load_acquire(char_field_addr(offset));     }
   394 inline void oopDesc::release_char_field_put(int offset, jchar contents)     { OrderAccess::release_store(char_field_addr(offset), contents); }
   396 inline jint oopDesc::int_field_acquire(int offset) const                    { return OrderAccess::load_acquire(int_field_addr(offset));      }
   397 inline void oopDesc::release_int_field_put(int offset, jint contents)       { OrderAccess::release_store(int_field_addr(offset), contents);  }
   399 inline jshort oopDesc::short_field_acquire(int offset) const                { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
   400 inline void oopDesc::release_short_field_put(int offset, jshort contents)   { OrderAccess::release_store(short_field_addr(offset), contents);     }
   402 inline jlong oopDesc::long_field_acquire(int offset) const                  { return OrderAccess::load_acquire(long_field_addr(offset));       }
   403 inline void oopDesc::release_long_field_put(int offset, jlong contents)     { OrderAccess::release_store(long_field_addr(offset), contents);   }
   405 inline jfloat oopDesc::float_field_acquire(int offset) const                { return OrderAccess::load_acquire(float_field_addr(offset));      }
   406 inline void oopDesc::release_float_field_put(int offset, jfloat contents)   { OrderAccess::release_store(float_field_addr(offset), contents);  }
   408 inline jdouble oopDesc::double_field_acquire(int offset) const              { return OrderAccess::load_acquire(double_field_addr(offset));     }
   409 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
   411 inline address oopDesc::address_field_acquire(int offset) const             { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
   412 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
   414 inline int oopDesc::size_given_klass(Klass* klass)  {
   415   int lh = klass->layout_helper();
   416   int s;
   418   // lh is now a value computed at class initialization that may hint
   419   // at the size.  For instances, this is positive and equal to the
   420   // size.  For arrays, this is negative and provides log2 of the
   421   // array element size.  For other oops, it is zero and thus requires
   422   // a virtual call.
   423   //
   424   // We go to all this trouble because the size computation is at the
   425   // heart of phase 2 of mark-compaction, and called for every object,
   426   // alive or dead.  So the speed here is equal in importance to the
   427   // speed of allocation.
   429   if (lh > Klass::_lh_neutral_value) {
   430     if (!Klass::layout_helper_needs_slow_path(lh)) {
   431       s = lh >> LogHeapWordSize;  // deliver size scaled by wordSize
   432     } else {
   433       s = klass->oop_size(this);
   434     }
   435   } else if (lh <= Klass::_lh_neutral_value) {
   436     // The most common case is instances; fall through if so.
   437     if (lh < Klass::_lh_neutral_value) {
   438       // Second most common case is arrays.  We have to fetch the
   439       // length of the array, shift (multiply) it appropriately,
   440       // up to wordSize, add the header, and align to object size.
   441       size_t size_in_bytes;
   442 #ifdef _M_IA64
   443       // The Windows Itanium Aug 2002 SDK hoists this load above
   444       // the check for s < 0.  An oop at the end of the heap will
   445       // cause an access violation if this load is performed on a non
   446       // array oop.  Making the reference volatile prohibits this.
   447       // (%%% please explain by what magic the length is actually fetched!)
   448       volatile int *array_length;
   449       array_length = (volatile int *)( (intptr_t)this +
   450                           arrayOopDesc::length_offset_in_bytes() );
   451       assert(array_length > 0, "Integer arithmetic problem somewhere");
   452       // Put into size_t to avoid overflow.
   453       size_in_bytes = (size_t) array_length;
   454       size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
   455 #else
   456       size_t array_length = (size_t) ((arrayOop)this)->length();
   457       size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
   458 #endif
   459       size_in_bytes += Klass::layout_helper_header_size(lh);
   461       // This code could be simplified, but by keeping array_header_in_bytes
   462       // in units of bytes and doing it this way we can round up just once,
   463       // skipping the intermediate round to HeapWordSize.  Cast the result
   464       // of round_to to size_t to guarantee unsigned division == right shift.
   465       s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
   466         HeapWordSize);
   468       // UseParNewGC, UseParallelGC and UseG1GC can change the length field
   469       // of an "old copy" of an object array in the young gen so it indicates
   470       // the grey portion of an already copied array. This will cause the first
   471       // disjunct below to fail if the two comparands are computed across such
   472       // a concurrent change.
   473       // UseParNewGC also runs with promotion labs (which look like int
   474       // filler arrays) which are subject to changing their declared size
   475       // when finally retiring a PLAB; this also can cause the first disjunct
   476       // to fail for another worker thread that is concurrently walking the block
   477       // offset table. Both these invariant failures are benign for their
   478       // current uses; we relax the assertion checking to cover these two cases below:
   479       //     is_objArray() && is_forwarded()   // covers first scenario above
   480       //  || is_typeArray()                    // covers second scenario above
   481       // If and when UseParallelGC uses the same obj array oop stealing/chunking
   482       // technique, we will need to suitably modify the assertion.
   483       assert((s == klass->oop_size(this)) ||
   484              (Universe::heap()->is_gc_active() &&
   485               ((is_typeArray() && UseParNewGC) ||
   486                (is_objArray()  && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
   487              "wrong array object size");
   488     } else {
   489       // Must be zero, so bite the bullet and take the virtual call.
   490       s = klass->oop_size(this);
   491     }
   492   }
   494   assert(s % MinObjAlignment == 0, "alignment check");
   495   assert(s > 0, "Bad size calculated");
   496   return s;
   497 }
   500 inline int oopDesc::size()  {
   501   return size_given_klass(klass());
   502 }
   504 inline void update_barrier_set(void* p, oop v, bool release = false) {
   505   assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
   506   oopDesc::bs()->write_ref_field(p, v, release);
   507 }
   509 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
   510   oopDesc::bs()->write_ref_field_pre(p, v);
   511 }
   513 template <class T> inline void oop_store(T* p, oop v) {
   514   if (always_do_update_barrier) {
   515     oop_store((volatile T*)p, v);
   516   } else {
   517     update_barrier_set_pre(p, v);
   518     oopDesc::encode_store_heap_oop(p, v);
   519     // always_do_update_barrier == false =>
   520     // Either we are at a safepoint (in GC) or CMS is not used. In both
   521     // cases it's unnecessary to mark the card as dirty with release sematics.
   522     update_barrier_set((void*)p, v, false /* release */);  // cast away type
   523   }
   524 }
   526 template <class T> inline void oop_store(volatile T* p, oop v) {
   527   update_barrier_set_pre((T*)p, v);   // cast away volatile
   528   // Used by release_obj_field_put, so use release_store_ptr.
   529   oopDesc::release_encode_store_heap_oop(p, v);
   530   // When using CMS we must mark the card corresponding to p as dirty
   531   // with release sematics to prevent that CMS sees the dirty card but
   532   // not the new value v at p due to reordering of the two
   533   // stores. Note that CMS has a concurrent precleaning phase, where
   534   // it reads the card table while the Java threads are running.
   535   update_barrier_set((void*)p, v, true /* release */);    // cast away type
   536 }
   538 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
   539 // (without having to remember the function name this calls).
   540 inline void oop_store_raw(HeapWord* addr, oop value) {
   541   if (UseCompressedOops) {
   542     oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
   543   } else {
   544     oopDesc::encode_store_heap_oop((oop*)addr, value);
   545   }
   546 }
   548 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
   549                                                 volatile HeapWord *dest,
   550                                                 oop compare_value,
   551                                                 bool prebarrier) {
   552   if (UseCompressedOops) {
   553     if (prebarrier) {
   554       update_barrier_set_pre((narrowOop*)dest, exchange_value);
   555     }
   556     // encode exchange and compare value from oop to T
   557     narrowOop val = encode_heap_oop(exchange_value);
   558     narrowOop cmp = encode_heap_oop(compare_value);
   560     narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
   561     // decode old from T to oop
   562     return decode_heap_oop(old);
   563   } else {
   564     if (prebarrier) {
   565       update_barrier_set_pre((oop*)dest, exchange_value);
   566     }
   567     return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
   568   }
   569 }
   571 // Used only for markSweep, scavenging
   572 inline bool oopDesc::is_gc_marked() const {
   573   return mark()->is_marked();
   574 }
   576 inline bool oopDesc::is_locked() const {
   577   return mark()->is_locked();
   578 }
   580 inline bool oopDesc::is_unlocked() const {
   581   return mark()->is_unlocked();
   582 }
   584 inline bool oopDesc::has_bias_pattern() const {
   585   return mark()->has_bias_pattern();
   586 }
   589 // used only for asserts
   590 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
   591   oop obj = (oop) this;
   592   if (!check_obj_alignment(obj)) return false;
   593   if (!Universe::heap()->is_in_reserved(obj)) return false;
   594   // obj is aligned and accessible in heap
   595   if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
   597   // Header verification: the mark is typically non-NULL. If we're
   598   // at a safepoint, it must not be null.
   599   // Outside of a safepoint, the header could be changing (for example,
   600   // another thread could be inflating a lock on this object).
   601   if (ignore_mark_word) {
   602     return true;
   603   }
   604   if (mark() != NULL) {
   605     return true;
   606   }
   607   return !SafepointSynchronize::is_at_safepoint();
   608 }
   611 // used only for asserts
   612 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
   613   return this == NULL ? true : is_oop(ignore_mark_word);
   614 }
   616 #ifndef PRODUCT
   617 // used only for asserts
   618 inline bool oopDesc::is_unlocked_oop() const {
   619   if (!Universe::heap()->is_in_reserved(this)) return false;
   620   return mark()->is_unlocked();
   621 }
   622 #endif // PRODUCT
   624 inline void oopDesc::follow_contents(void) {
   625   assert (is_gc_marked(), "should be marked");
   626   klass()->oop_follow_contents(this);
   627 }
   629 // Used by scavengers
   631 inline bool oopDesc::is_forwarded() const {
   632   // The extra heap check is needed since the obj might be locked, in which case the
   633   // mark would point to a stack location and have the sentinel bit cleared
   634   return mark()->is_marked();
   635 }
   637 // Used by scavengers
   638 inline void oopDesc::forward_to(oop p) {
   639   assert(check_obj_alignment(p),
   640          "forwarding to something not aligned");
   641   assert(Universe::heap()->is_in_reserved(p),
   642          "forwarding to something not in heap");
   643   markOop m = markOopDesc::encode_pointer_as_mark(p);
   644   assert(m->decode_pointer() == p, "encoding must be reversable");
   645   set_mark(m);
   646 }
   648 // Used by parallel scavengers
   649 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
   650   assert(check_obj_alignment(p),
   651          "forwarding to something not aligned");
   652   assert(Universe::heap()->is_in_reserved(p),
   653          "forwarding to something not in heap");
   654   markOop m = markOopDesc::encode_pointer_as_mark(p);
   655   assert(m->decode_pointer() == p, "encoding must be reversable");
   656   return cas_set_mark(m, compare) == compare;
   657 }
   659 // Note that the forwardee is not the same thing as the displaced_mark.
   660 // The forwardee is used when copying during scavenge and mark-sweep.
   661 // It does need to clear the low two locking- and GC-related bits.
   662 inline oop oopDesc::forwardee() const {
   663   return (oop) mark()->decode_pointer();
   664 }
   666 inline bool oopDesc::has_displaced_mark() const {
   667   return mark()->has_displaced_mark_helper();
   668 }
   670 inline markOop oopDesc::displaced_mark() const {
   671   return mark()->displaced_mark_helper();
   672 }
   674 inline void oopDesc::set_displaced_mark(markOop m) {
   675   mark()->set_displaced_mark_helper(m);
   676 }
   678 // The following method needs to be MT safe.
   679 inline uint oopDesc::age() const {
   680   assert(!is_forwarded(), "Attempt to read age from forwarded mark");
   681   if (has_displaced_mark()) {
   682     return displaced_mark()->age();
   683   } else {
   684     return mark()->age();
   685   }
   686 }
   688 inline void oopDesc::incr_age() {
   689   assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
   690   if (has_displaced_mark()) {
   691     set_displaced_mark(displaced_mark()->incr_age());
   692   } else {
   693     set_mark(mark()->incr_age());
   694   }
   695 }
   698 inline intptr_t oopDesc::identity_hash() {
   699   // Fast case; if the object is unlocked and the hash value is set, no locking is needed
   700   // Note: The mark must be read into local variable to avoid concurrent updates.
   701   markOop mrk = mark();
   702   if (mrk->is_unlocked() && !mrk->has_no_hash()) {
   703     return mrk->hash();
   704   } else if (mrk->is_marked()) {
   705     return mrk->hash();
   706   } else {
   707     return slow_identity_hash();
   708   }
   709 }
   711 inline int oopDesc::adjust_pointers() {
   712   debug_only(int check_size = size());
   713   int s = klass()->oop_adjust_pointers(this);
   714   assert(s == check_size, "should be the same");
   715   return s;
   716 }
   718 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix)                        \
   719                                                                            \
   720 inline int oopDesc::oop_iterate(OopClosureType* blk) {                     \
   721   SpecializationStats::record_call();                                      \
   722   return klass()->oop_oop_iterate##nv_suffix(this, blk);               \
   723 }                                                                          \
   724                                                                            \
   725 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) {       \
   726   SpecializationStats::record_call();                                      \
   727   return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr);       \
   728 }
   731 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
   732   // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
   733   // the do_oop calls, but turns off all other features in ExtendedOopClosure.
   734   NoHeaderExtendedOopClosure cl(blk);
   735   return oop_iterate(&cl);
   736 }
   738 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
   739   NoHeaderExtendedOopClosure cl(blk);
   740   return oop_iterate(&cl, mr);
   741 }
   743 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
   744 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
   746 #if INCLUDE_ALL_GCS
   747 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix)              \
   748                                                                            \
   749 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) {           \
   750   SpecializationStats::record_call();                                      \
   751   return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk);     \
   752 }
   754 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
   755 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
   756 #endif // INCLUDE_ALL_GCS
   758 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP

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