/*

 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

#ifndef SHARE_VM_OOPS_OOP_INLINE_HPP

#define SHARE_VM_OOPS_OOP_INLINE_HPP

#include "gc/shared/ageTable.hpp"

#include "gc/shared/barrierSet.inline.hpp"

#include "gc/shared/cardTableModRefBS.hpp"

#include "gc/shared/collectedHeap.inline.hpp"

#include "gc/shared/genCollectedHeap.hpp"

#include "gc/shared/generation.hpp"

#include "oops/arrayKlass.hpp"

#include "oops/arrayOop.hpp"

#include "oops/klass.inline.hpp"

#include "oops/markOop.inline.hpp"

#include "oops/oop.hpp"

#include "runtime/atomic.hpp"

#include "runtime/orderAccess.inline.hpp"

#include "runtime/os.hpp"

#include "utilities/macros.hpp"

inline void update_barrier_set(void* p, oop v, bool release = false) {

  assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");

  oopDesc::bs()->write_ref_field(p, v, release);

}

template <class T> inline void update_barrier_set_pre(T* p, oop v) {

  oopDesc::bs()->write_ref_field_pre(p, v);

}

template <class T> void oop_store(T* p, oop v) {

  if (always_do_update_barrier) {

    oop_store((volatile T*)p, v);

  } else {

    update_barrier_set_pre(p, v);

    oopDesc::encode_store_heap_oop(p, v);

    // always_do_update_barrier == false =>

    // Either we are at a safepoint (in GC) or CMS is not used. In both

    // cases it's unnecessary to mark the card as dirty with release sematics.

    update_barrier_set((void*)p, v, false /* release */);  // cast away type

  }

}

template <class T> void oop_store(volatile T* p, oop v) {

  update_barrier_set_pre((T*)p, v);   // cast away volatile

  // Used by release_obj_field_put, so use release_store_ptr.

  oopDesc::release_encode_store_heap_oop(p, v);

  // When using CMS we must mark the card corresponding to p as dirty

  // with release sematics to prevent that CMS sees the dirty card but

  // not the new value v at p due to reordering of the two

  // stores. Note that CMS has a concurrent precleaning phase, where

  // it reads the card table while the Java threads are running.

  update_barrier_set((void*)p, v, true /* release */);    // cast away type

}

// Should replace *addr = oop assignments where addr type depends on UseCompressedOops

// (without having to remember the function name this calls).

inline void oop_store_raw(HeapWord* addr, oop value) {

  if (UseCompressedOops) {

    oopDesc::encode_store_heap_oop((narrowOop*)addr, value);

  } else {

    oopDesc::encode_store_heap_oop((oop*)addr, value);

  }

}

// Implementation of all inlined member functions defined in oop.hpp

// We need a separate file to avoid circular references

void oopDesc::release_set_mark(markOop m) {

  OrderAccess::release_store_ptr(&_mark, m);

}

markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {

  return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);

}

void oopDesc::init_mark() {

  set_mark(markOopDesc::prototype_for_object(this));

}

Klass* oopDesc::klass() const {

  if (UseCompressedClassPointers) {

    return Klass::decode_klass_not_null(_metadata._compressed_klass);

  } else {

    return _metadata._klass;

  }

}

Klass* oopDesc::klass_or_null() const volatile {

  if (UseCompressedClassPointers) {

    return Klass::decode_klass(_metadata._compressed_klass);

  } else {

    return _metadata._klass;

  }

}

Klass* oopDesc::klass_or_null_acquire() const volatile {

  if (UseCompressedClassPointers) {

    // Workaround for non-const load_acquire parameter.

    const volatile narrowKlass* addr = &_metadata._compressed_klass;

    volatile narrowKlass* xaddr = const_cast<volatile narrowKlass*>(addr);

    return Klass::decode_klass(OrderAccess::load_acquire(xaddr));

  } else {

    return (Klass*)OrderAccess::load_ptr_acquire(&_metadata._klass);

  }

}

Klass** oopDesc::klass_addr() {

  // Only used internally and with CMS and will not work with

  // UseCompressedOops

  assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");

  return (Klass**) &_metadata._klass;

}

narrowKlass* oopDesc::compressed_klass_addr() {

  assert(UseCompressedClassPointers, "only called by compressed klass pointers");

  return &_metadata._compressed_klass;

}

#define CHECK_SET_KLASS(k)                                                \

  do {                                                                    \

    assert(Universe::is_bootstrapping() || k != NULL, "NULL Klass");      \

    assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass"); \

  } while (0)

void oopDesc::set_klass(Klass* k) {

  CHECK_SET_KLASS(k);

  if (UseCompressedClassPointers) {

    *compressed_klass_addr() = Klass::encode_klass_not_null(k);

  } else {

    *klass_addr() = k;

  }

}

void oopDesc::release_set_klass(Klass* k) {

  CHECK_SET_KLASS(k);

  if (UseCompressedClassPointers) {

    OrderAccess::release_store(compressed_klass_addr(),

                               Klass::encode_klass_not_null(k));

  } else {

    OrderAccess::release_store_ptr(klass_addr(), k);

  }

}

#undef CHECK_SET_KLASS

int oopDesc::klass_gap() const {

  return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());

}

void oopDesc::set_klass_gap(int v) {

  if (UseCompressedClassPointers) {

    *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;

  }

}

void oopDesc::set_klass_to_list_ptr(oop k) {

  // This is only to be used during GC, for from-space objects, so no

  // barrier is needed.

  if (UseCompressedClassPointers) {

    _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k);  // may be null (parnew overflow handling)

  } else {

    _metadata._klass = (Klass*)(address)k;

  }

}

oop oopDesc::list_ptr_from_klass() {

  // This is only to be used during GC, for from-space objects.

  if (UseCompressedClassPointers) {

    return decode_heap_oop((narrowOop)_metadata._compressed_klass);

  } else {

    // Special case for GC

    return (oop)(address)_metadata._klass;

  }

}

bool oopDesc::is_a(Klass* k) const {

  return klass()->is_subtype_of(k);

}

int oopDesc::size()  {

  return size_given_klass(klass());

}

int oopDesc::size_given_klass(Klass* klass)  {

  int lh = klass->layout_helper();

  int s;

  // lh is now a value computed at class initialization that may hint

  // at the size.  For instances, this is positive and equal to the

  // size.  For arrays, this is negative and provides log2 of the

  // array element size.  For other oops, it is zero and thus requires

  // a virtual call.

  //

  // We go to all this trouble because the size computation is at the

  // heart of phase 2 of mark-compaction, and called for every object,

  // alive or dead.  So the speed here is equal in importance to the

  // speed of allocation.

  if (lh > Klass::_lh_neutral_value) {

    if (!Klass::layout_helper_needs_slow_path(lh)) {

      s = lh >> LogHeapWordSize;  // deliver size scaled by wordSize

    } else {

      s = klass->oop_size(this);

    }

  } else if (lh <= Klass::_lh_neutral_value) {

    // The most common case is instances; fall through if so.

    if (lh < Klass::_lh_neutral_value) {

      // Second most common case is arrays.  We have to fetch the

      // length of the array, shift (multiply) it appropriately,

      // up to wordSize, add the header, and align to object size.

      size_t size_in_bytes;

#ifdef _M_IA64

      // The Windows Itanium Aug 2002 SDK hoists this load above

      // the check for s < 0.  An oop at the end of the heap will

      // cause an access violation if this load is performed on a non

      // array oop.  Making the reference volatile prohibits this.

      // (%%% please explain by what magic the length is actually fetched!)

      volatile int *array_length;

      array_length = (volatile int *)( (intptr_t)this +

                          arrayOopDesc::length_offset_in_bytes() );

      assert(array_length > 0, "Integer arithmetic problem somewhere");

      // Put into size_t to avoid overflow.

      size_in_bytes = (size_t) array_length;

      size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);

#else

      size_t array_length = (size_t) ((arrayOop)this)->length();

      size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);

#endif

      size_in_bytes += Klass::layout_helper_header_size(lh);

      // This code could be simplified, but by keeping array_header_in_bytes

      // in units of bytes and doing it this way we can round up just once,

      // skipping the intermediate round to HeapWordSize.  Cast the result

      // of round_to to size_t to guarantee unsigned division == right shift.

      s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /

        HeapWordSize);

      // ParNew (used by CMS), UseParallelGC and UseG1GC can change the length field

      // of an "old copy" of an object array in the young gen so it indicates

      // the grey portion of an already copied array. This will cause the first

      // disjunct below to fail if the two comparands are computed across such

      // a concurrent change.

      // ParNew also runs with promotion labs (which look like int

      // filler arrays) which are subject to changing their declared size

      // when finally retiring a PLAB; this also can cause the first disjunct

      // to fail for another worker thread that is concurrently walking the block

      // offset table. Both these invariant failures are benign for their

      // current uses; we relax the assertion checking to cover these two cases below:

      //     is_objArray() && is_forwarded()   // covers first scenario above

      //  || is_typeArray()                    // covers second scenario above

      // If and when UseParallelGC uses the same obj array oop stealing/chunking

      // technique, we will need to suitably modify the assertion.

      assert((s == klass->oop_size(this)) ||

             (Universe::heap()->is_gc_active() &&

              ((is_typeArray() && UseConcMarkSweepGC) ||

               (is_objArray()  && is_forwarded() && (UseConcMarkSweepGC || UseParallelGC || UseG1GC)))),

             "wrong array object size");

    } else {

      // Must be zero, so bite the bullet and take the virtual call.

      s = klass->oop_size(this);

    }

  }

  assert(s % MinObjAlignment == 0, "Oop size is not properly aligned: %d", s);

  assert(s > 0, "Oop size must be greater than zero, not %d", s);

  return s;

}

bool oopDesc::is_instance()  const { return klass()->is_instance_klass();  }

bool oopDesc::is_array()     const { return klass()->is_array_klass();     }

bool oopDesc::is_objArray()  const { return klass()->is_objArray_klass();  }

bool oopDesc::is_typeArray() const { return klass()->is_typeArray_klass(); }

void*      oopDesc::field_base(int offset)          const { return (void*)&((char*)this)[offset]; }

jbyte*     oopDesc::byte_field_addr(int offset)     const { return (jbyte*)    field_base(offset); }

jchar*     oopDesc::char_field_addr(int offset)     const { return (jchar*)    field_base(offset); }

jboolean*  oopDesc::bool_field_addr(int offset)     const { return (jboolean*) field_base(offset); }

jint*      oopDesc::int_field_addr(int offset)      const { return (jint*)     field_base(offset); }

jshort*    oopDesc::short_field_addr(int offset)    const { return (jshort*)   field_base(offset); }

jlong*     oopDesc::long_field_addr(int offset)     const { return (jlong*)    field_base(offset); }

jfloat*    oopDesc::float_field_addr(int offset)    const { return (jfloat*)   field_base(offset); }

jdouble*   oopDesc::double_field_addr(int offset)   const { return (jdouble*)  field_base(offset); }

Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }

template <class T> T* oopDesc::obj_field_addr(int offset) const { return (T*)  field_base(offset); }

address*   oopDesc::address_field_addr(int offset)  const { return (address*)  field_base(offset); }

// Functions for getting and setting oops within instance objects.

// If the oops are compressed, the type passed to these overloaded functions

// is narrowOop.  All functions are overloaded so they can be called by

// template functions without conditionals (the compiler instantiates via

// the right type and inlines the appopriate code).

// Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit

// offset from the heap base.  Saving the check for null can save instructions

// in inner GC loops so these are separated.

inline bool check_obj_alignment(oop obj) {

  return (cast_from_oop<intptr_t>(obj) & MinObjAlignmentInBytesMask) == 0;

}

oop oopDesc::decode_heap_oop_not_null(narrowOop v) {

  assert(!is_null(v), "narrow oop value can never be zero");

  address base = Universe::narrow_oop_base();

  int    shift = Universe::narrow_oop_shift();

  oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));

  assert(check_obj_alignment(result), "address not aligned: " INTPTR_FORMAT, p2i((void*) result));

  return result;

}

oop oopDesc::decode_heap_oop(narrowOop v) {

  return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);

}

narrowOop oopDesc::encode_heap_oop_not_null(oop v) {

  assert(!is_null(v), "oop value can never be zero");

  assert(check_obj_alignment(v), "Address not aligned");

  assert(Universe::heap()->is_in_reserved(v), "Address not in heap");

  address base = Universe::narrow_oop_base();

  int    shift = Universe::narrow_oop_shift();

  uint64_t  pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));

  assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");

  uint64_t result = pd >> shift;

  assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");

  assert(decode_heap_oop(result) == v, "reversibility");

  return (narrowOop)result;

}

narrowOop oopDesc::encode_heap_oop(oop v) {

  return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);

}

// Load and decode an oop out of the Java heap into a wide oop.

oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {

  return decode_heap_oop_not_null(*p);

}

// Load and decode an oop out of the heap accepting null

oop oopDesc::load_decode_heap_oop(narrowOop* p) {

  return decode_heap_oop(*p);

}

// Encode and store a heap oop.

void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {

  *p = encode_heap_oop_not_null(v);

}

// Encode and store a heap oop allowing for null.

void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {

  *p = encode_heap_oop(v);

}

// Store heap oop as is for volatile fields.

void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {

  OrderAccess::release_store_ptr(p, v);

}

void oopDesc::release_store_heap_oop(volatile narrowOop* p, narrowOop v) {

  OrderAccess::release_store(p, v);

}

void oopDesc::release_encode_store_heap_oop_not_null(volatile narrowOop* p, oop v) {

  // heap oop is not pointer sized.

  OrderAccess::release_store(p, encode_heap_oop_not_null(v));

}

void oopDesc::release_encode_store_heap_oop_not_null(volatile oop* p, oop v) {

  OrderAccess::release_store_ptr(p, v);

}

void oopDesc::release_encode_store_heap_oop(volatile oop* p, oop v) {

  OrderAccess::release_store_ptr(p, v);

}

void oopDesc::release_encode_store_heap_oop(volatile narrowOop* p, oop v) {

  OrderAccess::release_store(p, encode_heap_oop(v));

}

// These functions are only used to exchange oop fields in instances,

// not headers.

oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {

  if (UseCompressedOops) {

    // encode exchange value from oop to T

    narrowOop val = encode_heap_oop(exchange_value);

    narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);

    // decode old from T to oop

    return decode_heap_oop(old);

  } else {

    return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);

  }

}

oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,

                                         volatile HeapWord *dest,

                                         oop compare_value,

                                         bool prebarrier) {

  if (UseCompressedOops) {

    if (prebarrier) {

      update_barrier_set_pre((narrowOop*)dest, exchange_value);

    }

    // encode exchange and compare value from oop to T

    narrowOop val = encode_heap_oop(exchange_value);

    narrowOop cmp = encode_heap_oop(compare_value);

    narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);

    // decode old from T to oop

    return decode_heap_oop(old);

  } else {

    if (prebarrier) {

      update_barrier_set_pre((oop*)dest, exchange_value);

    }

    return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);

  }

}

// In order to put or get a field out of an instance, must first check

// if the field has been compressed and uncompress it.

oop oopDesc::obj_field(int offset) const {

  return UseCompressedOops ?

    load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :

    load_decode_heap_oop(obj_field_addr<oop>(offset));

}

void oopDesc::obj_field_put(int offset, oop value) {

  UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :

                      oop_store(obj_field_addr<oop>(offset),       value);

}

void oopDesc::obj_field_put_raw(int offset, oop value) {

  UseCompressedOops ?

    encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :

    encode_store_heap_oop(obj_field_addr<oop>(offset),       value);

}

void oopDesc::obj_field_put_volatile(int offset, oop value) {

  OrderAccess::release();

  obj_field_put(offset, value);

  OrderAccess::fence();

}

Metadata* oopDesc::metadata_field(int offset) const           { return *metadata_field_addr(offset);   }

void oopDesc::metadata_field_put(int offset, Metadata* value) { *metadata_field_addr(offset) = value;  }

jbyte oopDesc::byte_field(int offset) const                   { return (jbyte) *byte_field_addr(offset);    }

void oopDesc::byte_field_put(int offset, jbyte contents)      { *byte_field_addr(offset) = (jint) contents; }

jchar oopDesc::char_field(int offset) const                   { return (jchar) *char_field_addr(offset);    }

void oopDesc::char_field_put(int offset, jchar contents)      { *char_field_addr(offset) = (jint) contents; }

jboolean oopDesc::bool_field(int offset) const                { return (jboolean) *bool_field_addr(offset); }

void oopDesc::bool_field_put(int offset, jboolean contents)   { *bool_field_addr(offset) = (((jint) contents) & 1); }

jint oopDesc::int_field(int offset) const                     { return *int_field_addr(offset);        }

void oopDesc::int_field_put(int offset, jint contents)        { *int_field_addr(offset) = contents;    }

jshort oopDesc::short_field(int offset) const                 { return (jshort) *short_field_addr(offset);  }

void oopDesc::short_field_put(int offset, jshort contents)    { *short_field_addr(offset) = (jint) contents;}

jlong oopDesc::long_field(int offset) const                   { return *long_field_addr(offset);       }

void oopDesc::long_field_put(int offset, jlong contents)      { *long_field_addr(offset) = contents;   }

jfloat oopDesc::float_field(int offset) const                 { return *float_field_addr(offset);      }

void oopDesc::float_field_put(int offset, jfloat contents)    { *float_field_addr(offset) = contents;  }

jdouble oopDesc::double_field(int offset) const               { return *double_field_addr(offset);     }

void oopDesc::double_field_put(int offset, jdouble contents)  { *double_field_addr(offset) = contents; }

address oopDesc::address_field(int offset) const              { return *address_field_addr(offset);     }

void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }

oop oopDesc::obj_field_acquire(int offset) const {

  return UseCompressedOops ?

             decode_heap_oop((narrowOop)

               OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))