Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 1999-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  *

  */

 #include "incls/_precompiled.incl"

 #include "incls/_ciObjectFactory.cpp.incl"

 // 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<ciObject*>* ciObjectFactory::_shared_ci_objects = 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_objects = new (arena) GrowableArray<ciObject*>(arena, expected_size, 0, NULL);

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

   if (_shared_ci_objects != NULL) {

     _ci_objects->appendAll(_shared_ci_objects);

   }

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

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

   _return_addresses =

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

   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_objects.

     int i;

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

       symbolHandle sym_handle = vmSymbolHandles::symbol_handle_at((vmSymbols::SID) i);

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

       ciSymbol* sym = new (_arena) ciSymbol(sym_handle);

       init_ident_of(sym);

       _shared_ci_symbols[i] = sym;

     }

 #ifdef ASSERT

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

       symbolHandle sym_handle = vmSymbolHandles::symbol_handle_at((vmSymbols::SID) i);

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

       assert(sym->get_oop() == sym_handle(), "oop must match");

     }

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

 #endif

   }

   _ci_objects = new (_arena) GrowableArray<ciObject*>(_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) {

       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);

   ciEnv::_method_klass_instance =

     get(Universe::methodKlassObj())->as_method_klass();

   ciEnv::_symbol_klass_instance =

     get(Universe::symbolKlassObj())->as_symbol_klass();

   ciEnv::_klass_klass_instance =

     get(Universe::klassKlassObj())->as_klass_klass();

   ciEnv::_instance_klass_klass_instance =

     get(Universe::instanceKlassKlassObj())

       ->as_instance_klass_klass();

   ciEnv::_type_array_klass_klass_instance =

     get(Universe::typeArrayKlassKlassObj())

       ->as_type_array_klass_klass();

   ciEnv::_obj_array_klass_klass_instance =

     get(Universe::objArrayKlassKlassObj())

       ->as_obj_array_klass_klass();

   ciEnv::_ArrayStoreException =

     get(SystemDictionary::ArrayStoreException_klass())

       ->as_instance_klass();

   ciEnv::_Class =

     get(SystemDictionary::class_klass())

       ->as_instance_klass();

   ciEnv::_ClassCastException =

     get(SystemDictionary::ClassCastException_klass())

       ->as_instance_klass();

   ciEnv::_Object =

     get(SystemDictionary::object_klass())

       ->as_instance_klass();

   ciEnv::_Throwable =

     get(SystemDictionary::throwable_klass())

       ->as_instance_klass();

   ciEnv::_Thread =

     get(SystemDictionary::thread_klass())

       ->as_instance_klass();

   ciEnv::_OutOfMemoryError =

     get(SystemDictionary::OutOfMemoryError_klass())

       ->as_instance_klass();

   ciEnv::_String =

     get(SystemDictionary::string_klass())

       ->as_instance_klass();

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

     len = _ci_objects->length();

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

       ciObject* obj = _ci_objects->at(i2);

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

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

       }

     }

   }

   ciEnv::_unloaded_cisymbol = (ciSymbol*) ciObjectFactory::get(vmSymbols::dummy_symbol_oop());

   // 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(Universe::boolArrayKlassObj());

   get(Universe::charArrayKlassObj());

   get(Universe::singleArrayKlassObj());

   get(Universe::doubleArrayKlassObj());

   get(Universe::byteArrayKlassObj());

   get(Universe::shortArrayKlassObj());

   get(Universe::intArrayKlassObj());

   get(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_objects = _ci_objects;

 }

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

 // 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;

 #ifdef ASSERT

   oop last = NULL;

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

     oop o = _ci_objects->at(j)->get_oop();

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

     last = o;

   }

 #endif // ASSERT

   int len = _ci_objects->length();

   int index = find(key, _ci_objects);

 #ifdef ASSERT

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

     if (_ci_objects->at(i)->get_oop() == key) {

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

     }

   }

 #endif

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

     // Check in the non-perm area before putting it in the list.

     NonPermObject* &bucket = find_non_perm(key);

     if (bucket != NULL) {

       return bucket->object();

     }

     // Check in the shared symbol area before putting it in the list.

     if (key->is_symbol()) {

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

       if (sid != vmSymbols::NO_SID) {

         // do not pollute the main cache with it

         return vm_symbol_at(sid);

       }

     }

     // 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);

     if (!keyHandle->is_perm()) {

       // Not a perm-space object.

       insert_non_perm(bucket, keyHandle(), new_object);

       return new_object;

     }

     new_object->set_perm();

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

       // creating the new object has recursively entered new objects

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

       index = find(keyHandle(), _ci_objects);

     }

     assert(!is_found_at(index, keyHandle(), _ci_objects), "no double insert");

     insert(index, new_object, _ci_objects);

     return new_object;

   }

   return _ci_objects->at(index);

 }

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

 // 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_symbol()) {

     symbolHandle h_o(THREAD, (symbolOop)o);

     return new (arena()) ciSymbol(h_o);

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

     KlassHandle h_k(THREAD, (klassOop)o);

     Klass* k = ((klassOop)o)->klass_part();

     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 (k->oop_is_method()) {

       return new (arena()) ciMethodKlass(h_k);

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

       return new (arena()) ciSymbolKlass(h_k);

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

       if (k->oop_is_objArrayKlass()) {

         return new (arena()) ciObjArrayKlassKlass(h_k);

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

         return new (arena()) ciTypeArrayKlassKlass(h_k);

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

         return new (arena()) ciInstanceKlassKlass(h_k);

       } else {

         assert(o == Universe::klassKlassObj(), "bad klassKlass");

         return new (arena()) ciKlassKlass(h_k);

       }

     }

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

     methodHandle h_m(THREAD, (methodOop)o);

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

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

     methodDataHandle h_md(THREAD, (methodDataOop)o);

     return new (arena()) ciMethodData(h_md);

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

     instanceHandle h_i(THREAD, (instanceOop)o);

     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::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) {

   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)) {

       // 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);

   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.

   ciKlass* new_klass = NULL;

   // Two cases: this is an unloaded objArrayKlass or an

   // unloaded instanceKlass.  Deal with both.

   if (name->byte_at(0) == '[') {

     // Decompose the name.'

     jint dimension = 0;

     symbolOop element_name = NULL;

     BasicType element_type= FieldType::get_array_info(name->get_symbolOop(),

                                                       &dimension,

                                                       &element_name,

                                                       THREAD);

     if (HAS_PENDING_EXCEPTION) {

       CLEAR_PENDING_EXCEPTION;

       CURRENT_THREAD_ENV->record_out_of_memory_failure();

       return ciEnv::_unloaded_ciobjarrayklass;

     }

     assert(element_type != T_ARRAY, "unsuccessful decomposition");

     ciKlass* element_klass = NULL;

     if (element_type == T_OBJECT) {

       ciEnv *env = CURRENT_THREAD_ENV;

       ciSymbol* ci_name = env->get_object(element_name)->as_symbol();

       element_klass =

         env->get_klass_by_name(accessing_klass, ci_name, false)->as_instance_klass();

     } else {

       assert(dimension > 1, "one dimensional type arrays are always loaded.");

       // The type array itself takes care of one of the dimensions.

       dimension--;

       // The element klass is a typeArrayKlass.

       element_klass = ciTypeArrayKlass::make(element_type);

     }

     new_klass = new (arena()) ciObjArrayKlass(name, element_klass, dimension);

   } else {

     jobject loader_handle = NULL;

     jobject domain_handle = NULL;

     if (accessing_klass != NULL) {

       loader_handle = accessing_klass->loader_handle();

       domain_handle = accessing_klass->protection_domain_handle();

     }

     new_klass = new (arena()) ciInstanceKlass(name, loader_handle, domain_handle);

   }

   init_ident_of(new_klass);

   _unloaded_klasses->append(new_klass);

   return new_klass;

 }

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

 // ciObjectFactory::get_empty_methodData

 //

 // Get the ciMethodData representing the methodData for a method with

 // none.

 ciMethodData* ciObjectFactory::get_empty_methodData() {

   ciMethodData* new_methodData = new (arena()) ciMethodData();

   init_ident_of(new_methodData);

   return new_methodData;

 }

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

 // ciObjectFactory::get_return_address

 //

 // Get a ciReturnAddress for a specified bci.

 ciReturnAddress* ciObjectFactory::get_return_address(int bci) {

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

     ciReturnAddress* entry = _return_addresses->at(i);

     if (entry->bci() == bci) {

       // We've found a match.

       return entry;

     }

   }

   ciReturnAddress* new_ret_addr = new (arena()) ciReturnAddress(bci);

   init_ident_of(new_ret_addr);

   _return_addresses->append(new_ret_addr);

   return new_ret_addr;

 }

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

 // ciObjectFactory::init_ident_of

 void ciObjectFactory::init_ident_of(ciObject* obj) {

   obj->set_ident(_next_ident++);

 }

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

 // ciObjectFactory::find

 //

 // Use binary search to find the position of this oop in the cache.

 // If there is no entry in the cache corresponding to this oop, return

 // the position at which the oop should be inserted.

 int ciObjectFactory::find(oop key, GrowableArray<ciObject*>* objects) {

   int min = 0;

   int max = objects->length()-1;

   // print_contents();

   while (max >= min) {

     int mid = (max + min) / 2;

     oop value = objects->at(mid)->get_oop();

     if (value < key) {

       min = mid + 1;

     } else if (value > key) {

       max = mid - 1;

     } else {

       return mid;

     }

   }

   return min;

 }

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

 // ciObjectFactory::is_found_at

 //

 // Verify that the binary seach found the given key.

 bool ciObjectFactory::is_found_at(int index, oop key, GrowableArray<ciObject*>* objects) {

   return (index < objects->length() &&

           objects->at(index)->get_oop() == key);

 }

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

 // ciObjectFactory::insert

 //

 // Insert a ciObject into the table at some index.

 void ciObjectFactory::insert(int index, ciObject* obj, GrowableArray<ciObject*>* objects) {

   int len = objects->length();

   if (len == index) {

     objects->append(obj);

   } else {

     objects->append(objects->at(len-1));

     int pos;

     for (pos = len-2; pos >= index; pos--) {

       objects->at_put(pos+1,objects->at(pos));

     }

     objects->at_put(index, obj);

   }

 #ifdef ASSERT

   oop last = NULL;

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

     oop o = objects->at(j)->get_oop();

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

     last = o;

   }

 #endif // ASSERT

 }

 static ciObjectFactory::NonPermObject* emptyBucket = NULL;

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

 // ciObjectFactory::find_non_perm

 //

 // Use a small hash table, hashed on the klass of the key.

 // If there is no entry in the cache corresponding to this oop, return

 // the null tail of the bucket into which the oop should be inserted.

 ciObjectFactory::NonPermObject* &ciObjectFactory::find_non_perm(oop key) {

   // Be careful:  is_perm might change from false to true.

   // Thus, there might be a matching perm object in the table.

   // If there is, this probe must find it.

   if (key->is_perm() && _non_perm_count == 0) {

     return emptyBucket;

   } else if (key->is_instance()) {

     if (key->klass() == SystemDictionary::class_klass()) {

       // class mirror instances are always perm

       return emptyBucket;

     }

     // fall through to probe

   } else if (key->is_array()) {

     // fall through to probe

   } else {

     // not an array or instance

     return emptyBucket;

   }

   ciObject* klass = get(key->klass());

   NonPermObject* *bp = &_non_perm_bucket[(unsigned) klass->hash() % NON_PERM_BUCKETS];

   for (NonPermObject* p; (p = (*bp)) != NULL; bp = &p->next()) {

     if (is_equal(p, key))  break;

   }

   return (*bp);

 }

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

 // Code for for NonPermObject

 //

 inline ciObjectFactory::NonPermObject::NonPermObject(ciObjectFactory::NonPermObject* &bucket, oop key, ciObject* object) {

   assert(ciObjectFactory::is_initialized(), "");

   _object = object;

   _next = bucket;

   bucket = this;

 }

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

 // ciObjectFactory::insert_non_perm

 //

 // Insert a ciObject into the non-perm table.

 void ciObjectFactory::insert_non_perm(ciObjectFactory::NonPermObject* &where, oop key, ciObject* obj) {

   assert(&where != &emptyBucket, "must not try to fill empty bucket");

   NonPermObject* p = new (arena()) NonPermObject(where, key, obj);

   assert(where == p && is_equal(p, key) && p->object() == obj, "entry must match");

   assert(find_non_perm(key) == p, "must find the same spot");

   ++_non_perm_count;

 }

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

 // ciObjectFactory::vm_symbol_at

 // Get the ciSymbol corresponding to some index in vmSymbols.

 ciSymbol* ciObjectFactory::vm_symbol_at(int index) {

   assert(index >= vmSymbols::FIRST_SID && index < vmSymbols::SID_LIMIT, "oob");

   return _shared_ci_symbols[index];

 }

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

 // ciObjectFactory::print_contents_impl

 void ciObjectFactory::print_contents_impl() {

   int len = _ci_objects->length();

   tty->print_cr("ciObjectFactory (%d) oop contents:", len);

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

     _ci_objects->at(i)->print();

     tty->cr();

   }

 }

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

 // ciObjectFactory::print_contents

 void ciObjectFactory::print_contents() {

   print();

   tty->cr();

   GUARDED_VM_ENTRY(print_contents_impl();)

 }

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

 // ciObjectFactory::print

 //

 // Print debugging information about the object factory

 void ciObjectFactory::print() {

   tty->print("<ciObjectFactory oops=%d unloaded_methods=%d unloaded_klasses=%d>",

              _ci_objects->length(), _unloaded_methods->length(),

              _unloaded_klasses->length());

 }