/*

 * Copyright (c) 1999, 2015, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "ci/ciCallSite.hpp"

#include "ci/ciInstance.hpp"

#include "ci/ciInstanceKlass.hpp"

#include "ci/ciMemberName.hpp"

#include "ci/ciMethod.hpp"

#include "ci/ciMethodData.hpp"

#include "ci/ciMethodHandle.hpp"

#include "ci/ciMethodType.hpp"

#include "ci/ciNullObject.hpp"

#include "ci/ciObjArray.hpp"

#include "ci/ciObjArrayKlass.hpp"

#include "ci/ciObject.hpp"

#include "ci/ciObjectFactory.hpp"

#include "ci/ciSymbol.hpp"

#include "ci/ciTypeArray.hpp"

#include "ci/ciTypeArrayKlass.hpp"

#include "ci/ciUtilities.hpp"

#include "classfile/javaClasses.inline.hpp"

#include "classfile/systemDictionary.hpp"

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

#include "memory/allocation.inline.hpp"

#include "oops/oop.inline.hpp"

#include "runtime/fieldType.hpp"

#include "utilities/macros.hpp"

#if INCLUDE_ALL_GCS

# include "gc/g1/g1SATBCardTableModRefBS.hpp"

#endif

// ciObjectFactory

//

// This class handles requests for the creation of new instances

// of ciObject and its subclasses.  It contains a caching mechanism

// which ensures that for each oop, at most one ciObject is created.

// This invariant allows more efficient implementation of ciObject.

//

// Implementation note: the oop->ciObject mapping is represented as

// a table stored in an array.  Even though objects are moved

// by the garbage collector, the compactor preserves their relative

// order; address comparison of oops (in perm space) is safe so long

// as we prohibit GC during our comparisons.  We currently use binary

// search to find the oop in the table, and inserting a new oop

// into the table may be costly.  If this cost ends up being

// problematic the underlying data structure can be switched to some

// sort of balanced binary tree.

GrowableArray<ciMetadata*>* ciObjectFactory::_shared_ci_metadata = NULL;

ciSymbol*                 ciObjectFactory::_shared_ci_symbols[vmSymbols::SID_LIMIT];

int                       ciObjectFactory::_shared_ident_limit = 0;

volatile bool             ciObjectFactory::_initialized = false;

// ------------------------------------------------------------------

// ciObjectFactory::ciObjectFactory

ciObjectFactory::ciObjectFactory(Arena* arena,

                                 int expected_size) {

  for (int i = 0; i < NON_PERM_BUCKETS; i++) {

    _non_perm_bucket[i] = NULL;

  }

  _non_perm_count = 0;

  _next_ident = _shared_ident_limit;

  _arena = arena;

  _ci_metadata = new (arena) GrowableArray<ciMetadata*>(arena, expected_size, 0, NULL);

  // If the shared ci objects exist append them to this factory's objects

  if (_shared_ci_metadata != NULL) {

    _ci_metadata->appendAll(_shared_ci_metadata);

  }

  _unloaded_methods = new (arena) GrowableArray<ciMethod*>(arena, 4, 0, NULL);

  _unloaded_klasses = new (arena) GrowableArray<ciKlass*>(arena, 8, 0, NULL);

  _unloaded_instances = new (arena) GrowableArray<ciInstance*>(arena, 4, 0, NULL);

  _return_addresses =

    new (arena) GrowableArray<ciReturnAddress*>(arena, 8, 0, NULL);

  _symbols = new (arena) GrowableArray<ciSymbol*>(arena, 100, 0, NULL);

}

// ------------------------------------------------------------------

// ciObjectFactory::ciObjectFactory

void ciObjectFactory::initialize() {

  ASSERT_IN_VM;

  JavaThread* thread = JavaThread::current();

  HandleMark  handle_mark(thread);

  // This Arena is long lived and exists in the resource mark of the

  // compiler thread that initializes the initial ciObjectFactory which

  // creates the shared ciObjects that all later ciObjectFactories use.

  Arena* arena = new (mtCompiler) Arena(mtCompiler);

  ciEnv initial(arena);

  ciEnv* env = ciEnv::current();

  env->_factory->init_shared_objects();

  _initialized = true;

}

void ciObjectFactory::init_shared_objects() {

  _next_ident = 1;  // start numbering CI objects at 1

  {

    // Create the shared symbols, but not in _shared_ci_metadata.

    int i;

    for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {

      Symbol* vmsym = vmSymbols::symbol_at((vmSymbols::SID) i);

      assert(vmSymbols::find_sid(vmsym) == i, "1-1 mapping");

      ciSymbol* sym = new (_arena) ciSymbol(vmsym, (vmSymbols::SID) i);

      init_ident_of(sym);

      _shared_ci_symbols[i] = sym;

    }

#ifdef ASSERT

    for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {

      Symbol* vmsym = vmSymbols::symbol_at((vmSymbols::SID) i);

      ciSymbol* sym = vm_symbol_at((vmSymbols::SID) i);

      assert(sym->get_symbol() == vmsym, "oop must match");

    }

    assert(ciSymbol::void_class_signature()->get_symbol() == vmSymbols::void_class_signature(), "spot check");

#endif

  }

  _ci_metadata = new (_arena) GrowableArray<ciMetadata*>(_arena, 64, 0, NULL);

  for (int i = T_BOOLEAN; i <= T_CONFLICT; i++) {

    BasicType t = (BasicType)i;

    if (type2name(t) != NULL && t != T_OBJECT && t != T_ARRAY && t != T_NARROWOOP && t != T_NARROWKLASS) {

      ciType::_basic_types[t] = new (_arena) ciType(t);

      init_ident_of(ciType::_basic_types[t]);

    }

  }

  ciEnv::_null_object_instance = new (_arena) ciNullObject();

  init_ident_of(ciEnv::_null_object_instance);

#define WK_KLASS_DEFN(name, ignore_s, opt)                              \

  if (SystemDictionary::name() != NULL) \

    ciEnv::_##name = get_metadata(SystemDictionary::name())->as_instance_klass();

  WK_KLASSES_DO(WK_KLASS_DEFN)

#undef WK_KLASS_DEFN

  for (int len = -1; len != _ci_metadata->length(); ) {

    len = _ci_metadata->length();

    for (int i2 = 0; i2 < len; i2++) {

      ciMetadata* obj = _ci_metadata->at(i2);

      assert (obj->is_metadata(), "what else would it be?");

      if (obj->is_loaded() && obj->is_instance_klass()) {

        obj->as_instance_klass()->compute_nonstatic_fields();

      }

    }

  }

  ciEnv::_unloaded_cisymbol = ciObjectFactory::get_symbol(vmSymbols::dummy_symbol());

  // Create dummy InstanceKlass and ObjArrayKlass object and assign them idents

  ciEnv::_unloaded_ciinstance_klass = new (_arena) ciInstanceKlass(ciEnv::_unloaded_cisymbol, NULL, NULL);

  init_ident_of(ciEnv::_unloaded_ciinstance_klass);

  ciEnv::_unloaded_ciobjarrayklass = new (_arena) ciObjArrayKlass(ciEnv::_unloaded_cisymbol, ciEnv::_unloaded_ciinstance_klass, 1);

  init_ident_of(ciEnv::_unloaded_ciobjarrayklass);

  assert(ciEnv::_unloaded_ciobjarrayklass->is_obj_array_klass(), "just checking");

  get_metadata(Universe::boolArrayKlassObj());

  get_metadata(Universe::charArrayKlassObj());

  get_metadata(Universe::singleArrayKlassObj());

  get_metadata(Universe::doubleArrayKlassObj());

  get_metadata(Universe::byteArrayKlassObj());

  get_metadata(Universe::shortArrayKlassObj());

  get_metadata(Universe::intArrayKlassObj());

  get_metadata(Universe::longArrayKlassObj());

  assert(_non_perm_count == 0, "no shared non-perm objects");

  // The shared_ident_limit is the first ident number that will

  // be used for non-shared objects.  That is, numbers less than

  // this limit are permanently assigned to shared CI objects,

  // while the higher numbers are recycled afresh by each new ciEnv.

  _shared_ident_limit = _next_ident;

  _shared_ci_metadata = _ci_metadata;

}

ciSymbol* ciObjectFactory::get_symbol(Symbol* key) {

  vmSymbols::SID sid = vmSymbols::find_sid(key);

  if (sid != vmSymbols::NO_SID) {

    // do not pollute the main cache with it

    return vm_symbol_at(sid);

  }

  assert(vmSymbols::find_sid(key) == vmSymbols::NO_SID, "");

  ciSymbol* s = new (arena()) ciSymbol(key, vmSymbols::NO_SID);

  _symbols->push(s);

  return s;

}

// Decrement the refcount when done on symbols referenced by this compilation.

void ciObjectFactory::remove_symbols() {

  for (int i = 0; i < _symbols->length(); i++) {

    ciSymbol* s = _symbols->at(i);

    s->get_symbol()->decrement_refcount();

  }

  // Since _symbols is resource allocated we're not allowed to delete it

  // but it'll go away just the same.

}

// ------------------------------------------------------------------

// ciObjectFactory::get

//

// Get the ciObject corresponding to some oop.  If the ciObject has

// already been created, it is returned.  Otherwise, a new ciObject

// is created.

ciObject* ciObjectFactory::get(oop key) {

  ASSERT_IN_VM;

  assert(Universe::heap()->is_in_reserved(key), "must be");

  NonPermObject* &bucket = find_non_perm(key);

  if (bucket != NULL) {

    return bucket->object();

  }

  // The ciObject does not yet exist.  Create it and insert it

  // into the cache.

  Handle keyHandle(key);

  ciObject* new_object = create_new_object(keyHandle());

  assert(keyHandle() == new_object->get_oop(), "must be properly recorded");

  init_ident_of(new_object);

  assert(Universe::heap()->is_in_reserved(new_object->get_oop()), "must be");

  // Not a perm-space object.

  insert_non_perm(bucket, keyHandle(), new_object);

  return new_object;

}

// ------------------------------------------------------------------

// ciObjectFactory::get_metadata

//

// Get the ciMetadata corresponding to some Metadata. If the ciMetadata has

// already been created, it is returned. Otherwise, a new ciMetadata

// is created.

ciMetadata* ciObjectFactory::get_metadata(Metadata* key) {

  ASSERT_IN_VM;

#ifdef ASSERT

  if (CIObjectFactoryVerify) {

    Metadata* last = NULL;

    for (int j = 0; j< _ci_metadata->length(); j++) {

      Metadata* o = _ci_metadata->at(j)->constant_encoding();

      assert(last < o, "out of order");

      last = o;

    }

  }

#endif // ASSERT

  int len = _ci_metadata->length();

  int index = find(key, _ci_metadata);

#ifdef ASSERT

  if (CIObjectFactoryVerify) {

    for (int i=0; i<_ci_metadata->length(); i++) {

      if (_ci_metadata->at(i)->constant_encoding() == key) {

        assert(index == i, " bad lookup");

      }

    }

  }

#endif

  if (!is_found_at(index, key, _ci_metadata)) {

    // The ciMetadata does not yet exist. Create it and insert it

    // into the cache.

    ciMetadata* new_object = create_new_metadata(key);

    init_ident_of(new_object);

    assert(new_object->is_metadata(), "must be");

    if (len != _ci_metadata->length()) {

      // creating the new object has recursively entered new objects

      // into the table.  We need to recompute our index.

      index = find(key, _ci_metadata);

    }

    assert(!is_found_at(index, key, _ci_metadata), "no double insert");

    insert(index, new_object, _ci_metadata);

    return new_object;

  }

  return _ci_metadata->at(index)->as_metadata();

}

// ------------------------------------------------------------------

// ciObjectFactory::create_new_object

//

// Create a new ciObject from an oop.

//

// Implementation note: this functionality could be virtual behavior

// of the oop itself.  For now, we explicitly marshal the object.

ciObject* ciObjectFactory::create_new_object(oop o) {

  EXCEPTION_CONTEXT;

  if (o->is_instance()) {

    instanceHandle h_i(THREAD, (instanceOop)o);

    if (java_lang_invoke_CallSite::is_instance(o))

      return new (arena()) ciCallSite(h_i);

    else if (java_lang_invoke_MemberName::is_instance(o))

      return new (arena()) ciMemberName(h_i);

    else if (java_lang_invoke_MethodHandle::is_instance(o))

      return new (arena()) ciMethodHandle(h_i);

    else if (java_lang_invoke_MethodType::is_instance(o))

      return new (arena()) ciMethodType(h_i);

    else

      return new (arena()) ciInstance(h_i);

  } else if (o->is_objArray()) {

    objArrayHandle h_oa(THREAD, (objArrayOop)o);

    return new (arena()) ciObjArray(h_oa);

  } else if (o->is_typeArray()) {

    typeArrayHandle h_ta(THREAD, (typeArrayOop)o);

    return new (arena()) ciTypeArray(h_ta);

  }

  // The oop is of some type not supported by the compiler interface.

  ShouldNotReachHere();

  return NULL;

}

// ------------------------------------------------------------------

// ciObjectFactory::create_new_metadata

//

// Create a new ciMetadata from a Metadata*.

//

// Implementation note: in order to keep Metadata live, an auxiliary ciObject

// is used, which points to it's holder.

ciMetadata* ciObjectFactory::create_new_metadata(Metadata* o) {

  EXCEPTION_CONTEXT;

  // Hold metadata from unloading by keeping it's holder alive.

  if (_initialized && o->is_klass()) {

    Klass* holder = ((Klass*)o);

    if (holder->oop_is_instance() && InstanceKlass::cast(holder)->is_anonymous()) {

      // Though ciInstanceKlass records class loader oop, it's not enough to keep

      // VM anonymous classes alive (loader == NULL). Klass holder should be used instead.

      // It is enough to record a ciObject, since cached elements are never removed

      // during ciObjectFactory lifetime. ciObjectFactory itself is created for

      // every compilation and lives for the whole duration of the compilation.

      ciObject* h = get(holder->klass_holder());

    }

  }

  if (o->is_klass()) {

    KlassHandle h_k(THREAD, (Klass*)o);

    Klass* k = (Klass*)o;

    if (k->oop_is_instance()) {

      return new (arena()) ciInstanceKlass(h_k);

    } else if (k->oop_is_objArray()) {

      return new (arena()) ciObjArrayKlass(h_k);

    } else if (k->oop_is_typeArray()) {

      return new (arena()) ciTypeArrayKlass(h_k);

    }

  } else if (o->is_method()) {

    methodHandle h_m(THREAD, (Method*)o);

    ciEnv *env = CURRENT_THREAD_ENV;

    ciInstanceKlass* holder = env->get_instance_klass(h_m()->method_holder());

    return new (arena()) ciMethod(h_m, holder);

  } else if (o->is_methodData()) {

    // Hold methodHandle alive - might not be necessary ???

    methodHandle h_m(THREAD, ((MethodData*)o)->method());

    return new (arena()) ciMethodData((MethodData*)o);

  }

  // The Metadata* is of some type not supported by the compiler interface.

  ShouldNotReachHere();

  return NULL;

}

// ------------------------------------------------------------------

// ciObjectFactory::ensure_metadata_alive

//

// Ensure that the metadata wrapped by the ciMetadata is kept alive by GC.

// This is primarily useful for metadata which is considered as weak roots

// by the GC but need to be strong roots if reachable from a current compilation.

//

void ciObjectFactory::ensure_metadata_alive(ciMetadata* m) {

  ASSERT_IN_VM; // We're handling raw oops here.

#if INCLUDE_ALL_GCS

  if (!UseG1GC) {

    return;

  }

  Klass* metadata_owner_klass;

  if (m->is_klass()) {

    metadata_owner_klass = m->as_klass()->get_Klass();

  } else if (m->is_method()) {

    metadata_owner_klass = m->as_method()->get_Method()->constants()->pool_holder();

  } else {

    fatal("Not implemented for other types of metadata");

  }

  oop metadata_holder = metadata_owner_klass->klass_holder();

  if (metadata_holder != NULL) {

    G1SATBCardTableModRefBS::enqueue(metadata_holder);

  }

#endif

}

//------------------------------------------------------------------

// ciObjectFactory::get_unloaded_method

//

// Get the ciMethod representing an unloaded/unfound method.

//

// Implementation note: unloaded methods are currently stored in

// an unordered array, requiring a linear-time lookup for each

// unloaded method.  This may need to change.

ciMethod* ciObjectFactory::get_unloaded_method(ciInstanceKlass* holder,

                                               ciSymbol*        name,

                                               ciSymbol*        signature,

                                               ciInstanceKlass* accessor) {

  ciSignature* that = NULL;

  for (int i = 0; i < _unloaded_methods->length(); i++) {

    ciMethod* entry = _unloaded_methods->at(i);

    if (entry->holder()->equals(holder) &&

        entry->name()->equals(name) &&

        entry->signature()->as_symbol()->equals(signature)) {

      // Short-circuit slow resolve.

      if (entry->signature()->accessing_klass() == accessor) {

        // We've found a match.

        return entry;

      } else {

        // Lazily create ciSignature

        if (that == NULL)  that = new (arena()) ciSignature(accessor, constantPoolHandle(), signature);

        if (entry->signature()->equals(that)) {

          // We've found a match.

          return entry;

        }

      }

    }

  }

  // This is a new unloaded method.  Create it and stick it in

  // the cache.

  ciMethod* new_method = new (arena()) ciMethod(holder, name, signature, accessor);

  init_ident_of(new_method);

  _unloaded_methods->append(new_method);

  return new_method;

}

//------------------------------------------------------------------

// ciObjectFactory::get_unloaded_klass

//

// Get a ciKlass representing an unloaded klass.

//

// Implementation note: unloaded klasses are currently stored in

// an unordered array, requiring a linear-time lookup for each

// unloaded klass.  This may need to change.

ciKlass* ciObjectFactory::get_unloaded_klass(ciKlass* accessing_klass,

                                             ciSymbol* name,

                                             bool create_if_not_found) {

  EXCEPTION_CONTEXT;

  oop loader = NULL;

  oop domain = NULL;

  if (accessing_klass != NULL) {

    loader = accessing_klass->loader();

    domain = accessing_klass->protection_domain();

  }

  for (int i=0; i<_unloaded_klasses->length(); i++) {

    ciKlass* entry = _unloaded_klasses->at(i);

    if (entry->name()->equals(name) &&

        entry->loader() == loader &&

        entry->protection_domain() == domain) {

      // We've found a match.

      return entry;

    }

  }

  if (!create_if_not_found)

    return NULL;

  // This is a new unloaded klass.  Create it and stick it in

  // the cache.