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

Thu, 13 Jan 2011 22:15:41 -0800

author
never
date
Thu, 13 Jan 2011 22:15:41 -0800
changeset 2462
8012aa3ccede
parent 2314
f95d63e2154a
child 2497
3582bf76420e
permissions
-rw-r--r--

4926272: methodOopDesc::method_from_bcp is unsafe
Reviewed-by: coleenp, jrose, kvn, dcubed

     1 /*
     2  * Copyright (c) 1997, 2010, 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/compactingPermGenGen.hpp"
    34 #include "memory/genCollectedHeap.hpp"
    35 #include "memory/generation.hpp"
    36 #include "memory/permGen.hpp"
    37 #include "memory/specialized_oop_closures.hpp"
    38 #include "oops/arrayKlass.hpp"
    39 #include "oops/arrayOop.hpp"
    40 #include "oops/klass.hpp"
    41 #include "oops/klassOop.hpp"
    42 #include "oops/markOop.inline.hpp"
    43 #include "oops/oop.hpp"
    44 #include "runtime/atomic.hpp"
    45 #include "runtime/os.hpp"
    46 #ifdef TARGET_ARCH_x86
    47 # include "bytes_x86.hpp"
    48 #endif
    49 #ifdef TARGET_ARCH_sparc
    50 # include "bytes_sparc.hpp"
    51 #endif
    52 #ifdef TARGET_ARCH_zero
    53 # include "bytes_zero.hpp"
    54 #endif
    56 // Implementation of all inlined member functions defined in oop.hpp
    57 // We need a separate file to avoid circular references
    59 inline void oopDesc::release_set_mark(markOop m) {
    60   OrderAccess::release_store_ptr(&_mark, m);
    61 }
    63 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
    64   return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
    65 }
    67 inline klassOop oopDesc::klass() const {
    68   if (UseCompressedOops) {
    69     return (klassOop)decode_heap_oop_not_null(_metadata._compressed_klass);
    70   } else {
    71     return _metadata._klass;
    72   }
    73 }
    75 inline klassOop oopDesc::klass_or_null() const volatile {
    76   // can be NULL in CMS
    77   if (UseCompressedOops) {
    78     return (klassOop)decode_heap_oop(_metadata._compressed_klass);
    79   } else {
    80     return _metadata._klass;
    81   }
    82 }
    84 inline int oopDesc::klass_gap_offset_in_bytes() {
    85   assert(UseCompressedOops, "only applicable to compressed headers");
    86   return oopDesc::klass_offset_in_bytes() + sizeof(narrowOop);
    87 }
    89 inline oop* oopDesc::klass_addr() {
    90   // Only used internally and with CMS and will not work with
    91   // UseCompressedOops
    92   assert(!UseCompressedOops, "only supported with uncompressed oops");
    93   return (oop*) &_metadata._klass;
    94 }
    96 inline narrowOop* oopDesc::compressed_klass_addr() {
    97   assert(UseCompressedOops, "only called by compressed oops");
    98   return (narrowOop*) &_metadata._compressed_klass;
    99 }
   101 inline void oopDesc::set_klass(klassOop k) {
   102   // since klasses are promoted no store check is needed
   103   assert(Universe::is_bootstrapping() || k != NULL, "must be a real klassOop");
   104   assert(Universe::is_bootstrapping() || k->is_klass(), "not a klassOop");
   105   if (UseCompressedOops) {
   106     oop_store_without_check(compressed_klass_addr(), (oop)k);
   107   } else {
   108     oop_store_without_check(klass_addr(), (oop) k);
   109   }
   110 }
   112 inline int oopDesc::klass_gap() const {
   113   return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
   114 }
   116 inline void oopDesc::set_klass_gap(int v) {
   117   if (UseCompressedOops) {
   118     *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
   119   }
   120 }
   122 inline void oopDesc::set_klass_to_list_ptr(oop k) {
   123   // This is only to be used during GC, for from-space objects, so no
   124   // barrier is needed.
   125   if (UseCompressedOops) {
   126     _metadata._compressed_klass = encode_heap_oop(k);  // may be null (parnew overflow handling)
   127   } else {
   128     _metadata._klass = (klassOop)k;
   129   }
   130 }
   132 inline void   oopDesc::init_mark()                 { set_mark(markOopDesc::prototype_for_object(this)); }
   133 inline Klass* oopDesc::blueprint()           const { return klass()->klass_part(); }
   135 inline bool oopDesc::is_a(klassOop k)        const { return blueprint()->is_subtype_of(k); }
   137 inline bool oopDesc::is_instance()           const { return blueprint()->oop_is_instance(); }
   138 inline bool oopDesc::is_instanceRef()        const { return blueprint()->oop_is_instanceRef(); }
   139 inline bool oopDesc::is_array()              const { return blueprint()->oop_is_array(); }
   140 inline bool oopDesc::is_objArray()           const { return blueprint()->oop_is_objArray(); }
   141 inline bool oopDesc::is_typeArray()          const { return blueprint()->oop_is_typeArray(); }
   142 inline bool oopDesc::is_javaArray()          const { return blueprint()->oop_is_javaArray(); }
   143 inline bool oopDesc::is_symbol()             const { return blueprint()->oop_is_symbol(); }
   144 inline bool oopDesc::is_klass()              const { return blueprint()->oop_is_klass(); }
   145 inline bool oopDesc::is_thread()             const { return blueprint()->oop_is_thread(); }
   146 inline bool oopDesc::is_method()             const { return blueprint()->oop_is_method(); }
   147 inline bool oopDesc::is_constMethod()        const { return blueprint()->oop_is_constMethod(); }
   148 inline bool oopDesc::is_methodData()         const { return blueprint()->oop_is_methodData(); }
   149 inline bool oopDesc::is_constantPool()       const { return blueprint()->oop_is_constantPool(); }
   150 inline bool oopDesc::is_constantPoolCache()  const { return blueprint()->oop_is_constantPoolCache(); }
   151 inline bool oopDesc::is_compiledICHolder()   const { return blueprint()->oop_is_compiledICHolder(); }
   153 inline void*     oopDesc::field_base(int offset)        const { return (void*)&((char*)this)[offset]; }
   155 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
   156 inline jbyte*    oopDesc::byte_field_addr(int offset)   const { return (jbyte*)   field_base(offset); }
   157 inline jchar*    oopDesc::char_field_addr(int offset)   const { return (jchar*)   field_base(offset); }
   158 inline jboolean* oopDesc::bool_field_addr(int offset)   const { return (jboolean*)field_base(offset); }
   159 inline jint*     oopDesc::int_field_addr(int offset)    const { return (jint*)    field_base(offset); }
   160 inline jshort*   oopDesc::short_field_addr(int offset)  const { return (jshort*)  field_base(offset); }
   161 inline jlong*    oopDesc::long_field_addr(int offset)   const { return (jlong*)   field_base(offset); }
   162 inline jfloat*   oopDesc::float_field_addr(int offset)  const { return (jfloat*)  field_base(offset); }
   163 inline jdouble*  oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
   164 inline address*  oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
   167 // Functions for getting and setting oops within instance objects.
   168 // If the oops are compressed, the type passed to these overloaded functions
   169 // is narrowOop.  All functions are overloaded so they can be called by
   170 // template functions without conditionals (the compiler instantiates via
   171 // the right type and inlines the appopriate code).
   173 inline bool oopDesc::is_null(oop obj)       { return obj == NULL; }
   174 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
   176 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
   177 // offset from the heap base.  Saving the check for null can save instructions
   178 // in inner GC loops so these are separated.
   180 inline bool check_obj_alignment(oop obj) {
   181   return (intptr_t)obj % MinObjAlignmentInBytes == 0;
   182 }
   184 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
   185   assert(!is_null(v), "oop value can never be zero");
   186   assert(check_obj_alignment(v), "Address not aligned");
   187   assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
   188   address base = Universe::narrow_oop_base();
   189   int    shift = Universe::narrow_oop_shift();
   190   uint64_t  pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
   191   assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
   192   uint64_t result = pd >> shift;
   193   assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
   194   assert(decode_heap_oop(result) == v, "reversibility");
   195   return (narrowOop)result;
   196 }
   198 inline narrowOop oopDesc::encode_heap_oop(oop v) {
   199   return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
   200 }
   202 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
   203   assert(!is_null(v), "narrow oop value can never be zero");
   204   address base = Universe::narrow_oop_base();
   205   int    shift = Universe::narrow_oop_shift();
   206   oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
   207   assert(check_obj_alignment(result), err_msg("address not aligned: " PTR_FORMAT, (void*) result));
   208   return result;
   209 }
   211 inline oop oopDesc::decode_heap_oop(narrowOop v) {
   212   return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
   213 }
   215 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
   216 inline oop oopDesc::decode_heap_oop(oop v)  { return v; }
   218 // Load an oop out of the Java heap as is without decoding.
   219 // Called by GC to check for null before decoding.
   220 inline oop       oopDesc::load_heap_oop(oop* p)          { return *p; }
   221 inline narrowOop oopDesc::load_heap_oop(narrowOop* p)    { return *p; }
   223 // Load and decode an oop out of the Java heap into a wide oop.
   224 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p)       { return *p; }
   225 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
   226   return decode_heap_oop_not_null(*p);
   227 }
   229 // Load and decode an oop out of the heap accepting null
   230 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
   231 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
   232   return decode_heap_oop(*p);
   233 }
   235 // Store already encoded heap oop into the heap.
   236 inline void oopDesc::store_heap_oop(oop* p, oop v)                 { *p = v; }
   237 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v)     { *p = v; }
   239 // Encode and store a heap oop.
   240 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
   241   *p = encode_heap_oop_not_null(v);
   242 }
   243 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
   245 // Encode and store a heap oop allowing for null.
   246 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
   247   *p = encode_heap_oop(v);
   248 }
   249 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
   251 // Store heap oop as is for volatile fields.
   252 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
   253   OrderAccess::release_store_ptr(p, v);
   254 }
   255 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
   256                                             narrowOop v) {
   257   OrderAccess::release_store(p, v);
   258 }
   260 inline void oopDesc::release_encode_store_heap_oop_not_null(
   261                                                 volatile narrowOop* p, oop v) {
   262   // heap oop is not pointer sized.
   263   OrderAccess::release_store(p, encode_heap_oop_not_null(v));
   264 }
   266 inline void oopDesc::release_encode_store_heap_oop_not_null(
   267                                                       volatile oop* p, oop v) {
   268   OrderAccess::release_store_ptr(p, v);
   269 }
   271 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
   272                                                            oop v) {
   273   OrderAccess::release_store_ptr(p, v);
   274 }
   275 inline void oopDesc::release_encode_store_heap_oop(
   276                                                 volatile narrowOop* p, oop v) {
   277   OrderAccess::release_store(p, encode_heap_oop(v));
   278 }
   281 // These functions are only used to exchange oop fields in instances,
   282 // not headers.
   283 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
   284   if (UseCompressedOops) {
   285     // encode exchange value from oop to T
   286     narrowOop val = encode_heap_oop(exchange_value);
   287     narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
   288     // decode old from T to oop
   289     return decode_heap_oop(old);
   290   } else {
   291     return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
   292   }
   293 }
   295 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
   296                                                 volatile HeapWord *dest,
   297                                                 oop compare_value) {
   298   if (UseCompressedOops) {
   299     // encode exchange and compare value from oop to T
   300     narrowOop val = encode_heap_oop(exchange_value);
   301     narrowOop cmp = encode_heap_oop(compare_value);
   303     narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
   304     // decode old from T to oop
   305     return decode_heap_oop(old);
   306   } else {
   307     return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
   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 void oopDesc::obj_field_put(int offset, oop value) {
   319   UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
   320                       oop_store(obj_field_addr<oop>(offset),       value);
   321 }
   322 inline void oopDesc::obj_field_raw_put(int offset, oop value) {
   323   UseCompressedOops ?
   324     encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
   325     encode_store_heap_oop(obj_field_addr<oop>(offset),       value);
   326 }
   328 inline jbyte oopDesc::byte_field(int offset) const                  { return (jbyte) *byte_field_addr(offset);    }
   329 inline void oopDesc::byte_field_put(int offset, jbyte contents)     { *byte_field_addr(offset) = (jint) contents; }
   331 inline jboolean oopDesc::bool_field(int offset) const               { return (jboolean) *bool_field_addr(offset); }
   332 inline void oopDesc::bool_field_put(int offset, jboolean contents)  { *bool_field_addr(offset) = (jint) contents; }
   334 inline jchar oopDesc::char_field(int offset) const                  { return (jchar) *char_field_addr(offset);    }
   335 inline void oopDesc::char_field_put(int offset, jchar contents)     { *char_field_addr(offset) = (jint) contents; }
   337 inline jint oopDesc::int_field(int offset) const                    { return *int_field_addr(offset);        }
   338 inline void oopDesc::int_field_put(int offset, jint contents)       { *int_field_addr(offset) = contents;    }
   340 inline jshort oopDesc::short_field(int offset) const                { return (jshort) *short_field_addr(offset);  }
   341 inline void oopDesc::short_field_put(int offset, jshort contents)   { *short_field_addr(offset) = (jint) contents;}
   343 inline jlong oopDesc::long_field(int offset) const                  { return *long_field_addr(offset);       }
   344 inline void oopDesc::long_field_put(int offset, jlong contents)     { *long_field_addr(offset) = contents;   }
   346 inline jfloat oopDesc::float_field(int offset) const                { return *float_field_addr(offset);      }
   347 inline void oopDesc::float_field_put(int offset, jfloat contents)   { *float_field_addr(offset) = contents;  }
   349 inline jdouble oopDesc::double_field(int offset) const              { return *double_field_addr(offset);     }
   350 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
   352 inline address oopDesc::address_field(int offset) const              { return *address_field_addr(offset);     }
   353 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
   355 inline oop oopDesc::obj_field_acquire(int offset) const {
   356   return UseCompressedOops ?
   357              decode_heap_oop((narrowOop)
   358                OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
   359            : decode_heap_oop((oop)
   360                OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
   361 }
   362 inline void oopDesc::release_obj_field_put(int offset, oop value) {
   363   UseCompressedOops ?
   364     oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
   365     oop_store((volatile oop*)      obj_field_addr<oop>(offset),       value);
   366 }
   368 inline jbyte oopDesc::byte_field_acquire(int offset) const                  { return OrderAccess::load_acquire(byte_field_addr(offset));     }
   369 inline void oopDesc::release_byte_field_put(int offset, jbyte contents)     { OrderAccess::release_store(byte_field_addr(offset), contents); }
   371 inline jboolean oopDesc::bool_field_acquire(int offset) const               { return OrderAccess::load_acquire(bool_field_addr(offset));     }
   372 inline void oopDesc::release_bool_field_put(int offset, jboolean contents)  { OrderAccess::release_store(bool_field_addr(offset), contents); }
   374 inline jchar oopDesc::char_field_acquire(int offset) const                  { return OrderAccess::load_acquire(char_field_addr(offset));     }
   375 inline void oopDesc::release_char_field_put(int offset, jchar contents)     { OrderAccess::release_store(char_field_addr(offset), contents); }
   377 inline jint oopDesc::int_field_acquire(int offset) const                    { return OrderAccess::load_acquire(int_field_addr(offset));      }
   378 inline void oopDesc::release_int_field_put(int offset, jint contents)       { OrderAccess::release_store(int_field_addr(offset), contents);  }
   380 inline jshort oopDesc::short_field_acquire(int offset) const                { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
   381 inline void oopDesc::release_short_field_put(int offset, jshort contents)   { OrderAccess::release_store(short_field_addr(offset), contents);     }
   383 inline jlong oopDesc::long_field_acquire(int offset) const                  { return OrderAccess::load_acquire(long_field_addr(offset));       }
   384 inline void oopDesc::release_long_field_put(int offset, jlong contents)     { OrderAccess::release_store(long_field_addr(offset), contents);   }
   386 inline jfloat oopDesc::float_field_acquire(int offset) const                { return OrderAccess::load_acquire(float_field_addr(offset));      }
   387 inline void oopDesc::release_float_field_put(int offset, jfloat contents)   { OrderAccess::release_store(float_field_addr(offset), contents);  }
   389 inline jdouble oopDesc::double_field_acquire(int offset) const              { return OrderAccess::load_acquire(double_field_addr(offset));     }
   390 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
   392 inline address oopDesc::address_field_acquire(int offset) const             { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
   393 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
   395 inline int oopDesc::size_given_klass(Klass* klass)  {
   396   int lh = klass->layout_helper();
   397   int s  = lh >> LogHeapWordSize;  // deliver size scaled by wordSize
   399   // lh is now a value computed at class initialization that may hint
   400   // at the size.  For instances, this is positive and equal to the
   401   // size.  For arrays, this is negative and provides log2 of the
   402   // array element size.  For other oops, it is zero and thus requires
   403   // a virtual call.
   404   //
   405   // We go to all this trouble because the size computation is at the
   406   // heart of phase 2 of mark-compaction, and called for every object,
   407   // alive or dead.  So the speed here is equal in importance to the
   408   // speed of allocation.
   410   if (lh <= Klass::_lh_neutral_value) {
   411     // The most common case is instances; fall through if so.
   412     if (lh < Klass::_lh_neutral_value) {
   413       // Second most common case is arrays.  We have to fetch the
   414       // length of the array, shift (multiply) it appropriately,
   415       // up to wordSize, add the header, and align to object size.
   416       size_t size_in_bytes;
   417 #ifdef _M_IA64
   418       // The Windows Itanium Aug 2002 SDK hoists this load above
   419       // the check for s < 0.  An oop at the end of the heap will
   420       // cause an access violation if this load is performed on a non
   421       // array oop.  Making the reference volatile prohibits this.
   422       // (%%% please explain by what magic the length is actually fetched!)
   423       volatile int *array_length;
   424       array_length = (volatile int *)( (intptr_t)this +
   425                           arrayOopDesc::length_offset_in_bytes() );
   426       assert(array_length > 0, "Integer arithmetic problem somewhere");
   427       // Put into size_t to avoid overflow.
   428       size_in_bytes = (size_t) array_length;
   429       size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
   430 #else
   431       size_t array_length = (size_t) ((arrayOop)this)->length();
   432       size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
   433 #endif
   434       size_in_bytes += Klass::layout_helper_header_size(lh);
   436       // This code could be simplified, but by keeping array_header_in_bytes
   437       // in units of bytes and doing it this way we can round up just once,
   438       // skipping the intermediate round to HeapWordSize.  Cast the result
   439       // of round_to to size_t to guarantee unsigned division == right shift.
   440       s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
   441         HeapWordSize);
   443       // UseParNewGC, UseParallelGC and UseG1GC can change the length field
   444       // of an "old copy" of an object array in the young gen so it indicates
   445       // the grey portion of an already copied array. This will cause the first
   446       // disjunct below to fail if the two comparands are computed across such
   447       // a concurrent change.
   448       // UseParNewGC also runs with promotion labs (which look like int
   449       // filler arrays) which are subject to changing their declared size
   450       // when finally retiring a PLAB; this also can cause the first disjunct
   451       // to fail for another worker thread that is concurrently walking the block
   452       // offset table. Both these invariant failures are benign for their
   453       // current uses; we relax the assertion checking to cover these two cases below:
   454       //     is_objArray() && is_forwarded()   // covers first scenario above
   455       //  || is_typeArray()                    // covers second scenario above
   456       // If and when UseParallelGC uses the same obj array oop stealing/chunking
   457       // technique, we will need to suitably modify the assertion.
   458       assert((s == klass->oop_size(this)) ||
   459              (Universe::heap()->is_gc_active() &&
   460               ((is_typeArray() && UseParNewGC) ||
   461                (is_objArray()  && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
   462              "wrong array object size");
   463     } else {
   464       // Must be zero, so bite the bullet and take the virtual call.
   465       s = klass->oop_size(this);
   466     }
   467   }
   469   assert(s % MinObjAlignment == 0, "alignment check");
   470   assert(s > 0, "Bad size calculated");
   471   return s;
   472 }
   475 inline int oopDesc::size()  {
   476   return size_given_klass(blueprint());
   477 }
   479 inline bool oopDesc::is_parsable() {
   480   return blueprint()->oop_is_parsable(this);
   481 }
   483 inline bool oopDesc::is_conc_safe() {
   484   return blueprint()->oop_is_conc_safe(this);
   485 }
   487 inline void update_barrier_set(void* p, oop v) {
   488   assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
   489   oopDesc::bs()->write_ref_field(p, v);
   490 }
   492 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
   493   oopDesc::bs()->write_ref_field_pre(p, v);
   494 }
   496 template <class T> inline void oop_store(T* p, oop v) {
   497   if (always_do_update_barrier) {
   498     oop_store((volatile T*)p, v);
   499   } else {
   500     update_barrier_set_pre(p, v);
   501     oopDesc::encode_store_heap_oop(p, v);
   502     update_barrier_set((void*)p, v);  // cast away type
   503   }
   504 }
   506 template <class T> inline void oop_store(volatile T* p, oop v) {
   507   update_barrier_set_pre((T*)p, v);   // cast away volatile
   508   // Used by release_obj_field_put, so use release_store_ptr.
   509   oopDesc::release_encode_store_heap_oop(p, v);
   510   update_barrier_set((void*)p, v);    // cast away type
   511 }
   513 template <class T> inline void oop_store_without_check(T* p, oop v) {
   514   // XXX YSR FIX ME!!!
   515   if (always_do_update_barrier) {
   516     oop_store(p, v);
   517   } else {
   518     assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier(p, v),
   519            "oop store without store check failed");
   520     oopDesc::encode_store_heap_oop(p, v);
   521   }
   522 }
   524 // When it absolutely has to get there.
   525 template <class T> inline void oop_store_without_check(volatile T* p, oop v) {
   526   // XXX YSR FIX ME!!!
   527   if (always_do_update_barrier) {
   528     oop_store(p, v);
   529   } else {
   530     assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier((T*)p, v),
   531            "oop store without store check failed");
   532     oopDesc::release_encode_store_heap_oop(p, v);
   533   }
   534 }
   536 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
   537 // (without having to remember the function name this calls).
   538 inline void oop_store_raw(HeapWord* addr, oop value) {
   539   if (UseCompressedOops) {
   540     oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
   541   } else {
   542     oopDesc::encode_store_heap_oop((oop*)addr, value);
   543   }
   544 }
   546 // Used only for markSweep, scavenging
   547 inline bool oopDesc::is_gc_marked() const {
   548   return mark()->is_marked();
   549 }
   551 inline bool oopDesc::is_locked() const {
   552   return mark()->is_locked();
   553 }
   555 inline bool oopDesc::is_unlocked() const {
   556   return mark()->is_unlocked();
   557 }
   559 inline bool oopDesc::has_bias_pattern() const {
   560   return mark()->has_bias_pattern();
   561 }
   564 // used only for asserts
   565 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
   566   oop obj = (oop) this;
   567   if (!check_obj_alignment(obj)) return false;
   568   if (!Universe::heap()->is_in_reserved(obj)) return false;
   569   // obj is aligned and accessible in heap
   570   // try to find metaclass cycle safely without seg faulting on bad input
   571   // we should reach klassKlassObj by following klass link at most 3 times
   572   for (int i = 0; i < 3; i++) {
   573     obj = obj->klass_or_null();
   574     // klass should be aligned and in permspace
   575     if (!check_obj_alignment(obj)) return false;
   576     if (!Universe::heap()->is_in_permanent(obj)) return false;
   577   }
   578   if (obj != Universe::klassKlassObj()) {
   579     // During a dump, the _klassKlassObj moved to a shared space.
   580     if (DumpSharedSpaces && Universe::klassKlassObj()->is_shared()) {
   581       return true;
   582     }
   583     return false;
   584   }
   586   // Header verification: the mark is typically non-NULL. If we're
   587   // at a safepoint, it must not be null.
   588   // Outside of a safepoint, the header could be changing (for example,
   589   // another thread could be inflating a lock on this object).
   590   if (ignore_mark_word) {
   591     return true;
   592   }
   593   if (mark() != NULL) {
   594     return true;
   595   }
   596   return !SafepointSynchronize::is_at_safepoint();
   597 }
   600 // used only for asserts
   601 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
   602   return this == NULL ? true : is_oop(ignore_mark_word);
   603 }
   605 #ifndef PRODUCT
   606 // used only for asserts
   607 inline bool oopDesc::is_unlocked_oop() const {
   608   if (!Universe::heap()->is_in_reserved(this)) return false;
   609   return mark()->is_unlocked();
   610 }
   611 #endif // PRODUCT
   613 inline void oopDesc::follow_header() {
   614   if (UseCompressedOops) {
   615     MarkSweep::mark_and_push(compressed_klass_addr());
   616   } else {
   617     MarkSweep::mark_and_push(klass_addr());
   618   }
   619 }
   621 inline void oopDesc::follow_contents(void) {
   622   assert (is_gc_marked(), "should be marked");
   623   blueprint()->oop_follow_contents(this);
   624 }
   627 // Used by scavengers
   629 inline bool oopDesc::is_forwarded() const {
   630   // The extra heap check is needed since the obj might be locked, in which case the
   631   // mark would point to a stack location and have the sentinel bit cleared
   632   return mark()->is_marked();
   633 }
   635 // Used by scavengers
   636 inline void oopDesc::forward_to(oop p) {
   637   assert(check_obj_alignment(p),
   638          "forwarding to something not aligned");
   639   assert(Universe::heap()->is_in_reserved(p),
   640          "forwarding to something not in heap");
   641   markOop m = markOopDesc::encode_pointer_as_mark(p);
   642   assert(m->decode_pointer() == p, "encoding must be reversable");
   643   set_mark(m);
   644 }
   646 // Used by parallel scavengers
   647 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
   648   assert(check_obj_alignment(p),
   649          "forwarding to something not aligned");
   650   assert(Universe::heap()->is_in_reserved(p),
   651          "forwarding to something not in heap");
   652   markOop m = markOopDesc::encode_pointer_as_mark(p);
   653   assert(m->decode_pointer() == p, "encoding must be reversable");
   654   return cas_set_mark(m, compare) == compare;
   655 }
   657 // Note that the forwardee is not the same thing as the displaced_mark.
   658 // The forwardee is used when copying during scavenge and mark-sweep.
   659 // It does need to clear the low two locking- and GC-related bits.
   660 inline oop oopDesc::forwardee() const {
   661   return (oop) mark()->decode_pointer();
   662 }
   664 inline bool oopDesc::has_displaced_mark() const {
   665   return mark()->has_displaced_mark_helper();
   666 }
   668 inline markOop oopDesc::displaced_mark() const {
   669   return mark()->displaced_mark_helper();
   670 }
   672 inline void oopDesc::set_displaced_mark(markOop m) {
   673   mark()->set_displaced_mark_helper(m);
   674 }
   676 // The following method needs to be MT safe.
   677 inline int oopDesc::age() const {
   678   assert(!is_forwarded(), "Attempt to read age from forwarded mark");
   679   if (has_displaced_mark()) {
   680     return displaced_mark()->age();
   681   } else {
   682     return mark()->age();
   683   }
   684 }
   686 inline void oopDesc::incr_age() {
   687   assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
   688   if (has_displaced_mark()) {
   689     set_displaced_mark(displaced_mark()->incr_age());
   690   } else {
   691     set_mark(mark()->incr_age());
   692   }
   693 }
   696 inline intptr_t oopDesc::identity_hash() {
   697   // Fast case; if the object is unlocked and the hash value is set, no locking is needed
   698   // Note: The mark must be read into local variable to avoid concurrent updates.
   699   markOop mrk = mark();
   700   if (mrk->is_unlocked() && !mrk->has_no_hash()) {
   701     return mrk->hash();
   702   } else if (mrk->is_marked()) {
   703     return mrk->hash();
   704   } else {
   705     return slow_identity_hash();
   706   }
   707 }
   709 inline void oopDesc::oop_iterate_header(OopClosure* blk) {
   710   if (UseCompressedOops) {
   711     blk->do_oop(compressed_klass_addr());
   712   } else {
   713     blk->do_oop(klass_addr());
   714   }
   715 }
   717 inline void oopDesc::oop_iterate_header(OopClosure* blk, MemRegion mr) {
   718   if (UseCompressedOops) {
   719     if (mr.contains(compressed_klass_addr())) {
   720       blk->do_oop(compressed_klass_addr());
   721     }
   722   } else {
   723     if (mr.contains(klass_addr())) blk->do_oop(klass_addr());
   724   }
   725 }
   727 inline int oopDesc::adjust_pointers() {
   728   debug_only(int check_size = size());
   729   int s = blueprint()->oop_adjust_pointers(this);
   730   assert(s == check_size, "should be the same");
   731   return s;
   732 }
   734 inline void oopDesc::adjust_header() {
   735   if (UseCompressedOops) {
   736     MarkSweep::adjust_pointer(compressed_klass_addr());
   737   } else {
   738     MarkSweep::adjust_pointer(klass_addr());
   739   }
   740 }
   742 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix)                        \
   743                                                                            \
   744 inline int oopDesc::oop_iterate(OopClosureType* blk) {                     \
   745   SpecializationStats::record_call();                                      \
   746   return blueprint()->oop_oop_iterate##nv_suffix(this, blk);               \
   747 }                                                                          \
   748                                                                            \
   749 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) {       \
   750   SpecializationStats::record_call();                                      \
   751   return blueprint()->oop_oop_iterate##nv_suffix##_m(this, blk, mr);       \
   752 }
   754 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
   755 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
   757 #ifndef SERIALGC
   758 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix)              \
   759                                                                            \
   760 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) {           \
   761   SpecializationStats::record_call();                                      \
   762   return blueprint()->oop_oop_iterate_backwards##nv_suffix(this, blk);     \
   763 }
   765 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
   766 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
   767 #endif // !SERIALGC
   769 inline bool oopDesc::is_shared() const {
   770   return CompactingPermGenGen::is_shared(this);
   771 }
   773 inline bool oopDesc::is_shared_readonly() const {
   774   return CompactingPermGenGen::is_shared_readonly(this);
   775 }
   777 inline bool oopDesc::is_shared_readwrite() const {
   778   return CompactingPermGenGen::is_shared_readwrite(this);
   779 }
   781 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP

mercurial