/* * Copyright (c) 1997, 2018, 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 "classfile/moduleEntry.hpp" #include "classfile/packageEntry.hpp" #include "classfile/symbolTable.hpp" #include "classfile/systemDictionary.hpp" #include "classfile/vmSymbols.hpp" #include "gc/shared/collectedHeap.inline.hpp" #include "gc/shared/specialized_oop_closures.hpp" #include "memory/iterator.inline.hpp" #include "memory/metadataFactory.hpp" #include "memory/metaspaceClosure.hpp" #include "memory/resourceArea.hpp" #include "memory/universe.hpp" #include "oops/arrayKlass.inline.hpp" #include "oops/instanceKlass.hpp" #include "oops/klass.inline.hpp" #include "oops/objArrayKlass.inline.hpp" #include "oops/objArrayOop.inline.hpp" #include "oops/oop.inline.hpp" #include "oops/symbol.hpp" #include "runtime/handles.inline.hpp" #include "runtime/mutexLocker.hpp" #include "utilities/macros.hpp" ObjArrayKlass* ObjArrayKlass::allocate(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name, TRAPS) { assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(), "array klasses must be same size as InstanceKlass"); int size = ArrayKlass::static_size(ObjArrayKlass::header_size()); return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name); } Klass* ObjArrayKlass::allocate_objArray_klass(ClassLoaderData* loader_data, int n, Klass* element_klass, TRAPS) { // Eagerly allocate the direct array supertype. Klass* super_klass = NULL; if (!Universe::is_bootstrapping() || SystemDictionary::Object_klass_loaded()) { Klass* element_super = element_klass->super(); if (element_super != NULL) { // The element type has a direct super. E.g., String[] has direct super of Object[]. super_klass = element_super->array_klass_or_null(); bool supers_exist = super_klass != NULL; // Also, see if the element has secondary supertypes. // We need an array type for each. Array* element_supers = element_klass->secondary_supers(); for( int i = element_supers->length()-1; i >= 0; i-- ) { Klass* elem_super = element_supers->at(i); if (elem_super->array_klass_or_null() == NULL) { supers_exist = false; break; } } if (!supers_exist) { // Oops. Not allocated yet. Back out, allocate it, and retry. Klass* ek = NULL; { MutexUnlocker mu(MultiArray_lock); MutexUnlocker mc(Compile_lock); // for vtables super_klass = element_super->array_klass(CHECK_0); for( int i = element_supers->length()-1; i >= 0; i-- ) { Klass* elem_super = element_supers->at(i); elem_super->array_klass(CHECK_0); } // Now retry from the beginning ek = element_klass->array_klass(n, CHECK_0); } // re-lock return ek; } } else { // The element type is already Object. Object[] has direct super of Object. super_klass = SystemDictionary::Object_klass(); } } // Create type name for klass. Symbol* name = NULL; if (!element_klass->is_instance_klass() || (name = InstanceKlass::cast(element_klass)->array_name()) == NULL) { ResourceMark rm(THREAD); char *name_str = element_klass->name()->as_C_string(); int len = element_klass->name()->utf8_length(); char *new_str = NEW_RESOURCE_ARRAY(char, len + 4); int idx = 0; new_str[idx++] = '['; if (element_klass->is_instance_klass()) { // it could be an array or simple type new_str[idx++] = 'L'; } memcpy(&new_str[idx], name_str, len * sizeof(char)); idx += len; if (element_klass->is_instance_klass()) { new_str[idx++] = ';'; } new_str[idx++] = '\0'; name = SymbolTable::new_permanent_symbol(new_str, CHECK_0); if (element_klass->is_instance_klass()) { InstanceKlass* ik = InstanceKlass::cast(element_klass); ik->set_array_name(name); } } // Initialize instance variables ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, CHECK_0); // Add all classes to our internal class loader list here, // including classes in the bootstrap (NULL) class loader. // GC walks these as strong roots. loader_data->add_class(oak); ModuleEntry* module = oak->module(); assert(module != NULL, "No module entry for array"); // Call complete_create_array_klass after all instance variables has been initialized. ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_0); return oak; } ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name) : ArrayKlass(name) { this->set_dimension(n); this->set_element_klass(element_klass); // decrement refcount because object arrays are not explicitly freed. The // InstanceKlass array_name() keeps the name counted while the klass is // loaded. name->decrement_refcount(); Klass* bk; if (element_klass->is_objArray_klass()) { bk = ObjArrayKlass::cast(element_klass)->bottom_klass(); } else { bk = element_klass; } assert(bk != NULL && (bk->is_instance_klass() || bk->is_typeArray_klass()), "invalid bottom klass"); this->set_bottom_klass(bk); this->set_class_loader_data(bk->class_loader_data()); this->set_layout_helper(array_layout_helper(T_OBJECT)); assert(this->is_array_klass(), "sanity"); assert(this->is_objArray_klass(), "sanity"); } int ObjArrayKlass::oop_size(oop obj) const { assert(obj->is_objArray(), "must be object array"); return objArrayOop(obj)->object_size(); } objArrayOop ObjArrayKlass::allocate(int length, TRAPS) { if (length >= 0) { if (length <= arrayOopDesc::max_array_length(T_OBJECT)) { int size = objArrayOopDesc::object_size(length); return (objArrayOop)CollectedHeap::array_allocate(this, size, length, THREAD); } else { report_java_out_of_memory("Requested array size exceeds VM limit"); JvmtiExport::post_array_size_exhausted(); THROW_OOP_0(Universe::out_of_memory_error_array_size()); } } else { THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); } } static int multi_alloc_counter = 0; oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) { int length = *sizes; // Call to lower_dimension uses this pointer, so most be called before a // possible GC Klass* ld_klass = lower_dimension(); // If length < 0 allocate will throw an exception. objArrayOop array = allocate(length, CHECK_NULL); objArrayHandle h_array (THREAD, array); if (rank > 1) { if (length != 0) { for (int index = 0; index < length; index++) { ArrayKlass* ak = ArrayKlass::cast(ld_klass); oop sub_array = ak->multi_allocate(rank-1, &sizes[1], CHECK_NULL); h_array->obj_at_put(index, sub_array); } } else { // Since this array dimension has zero length, nothing will be // allocated, however the lower dimension values must be checked // for illegal values. for (int i = 0; i < rank - 1; ++i) { sizes += 1; if (*sizes < 0) { THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); } } } } return h_array(); } // Either oop or narrowOop depending on UseCompressedOops. template void ObjArrayKlass::do_copy(arrayOop s, T* src, arrayOop d, T* dst, int length, TRAPS) { if (s == d) { // since source and destination are equal we do not need conversion checks. assert(length > 0, "sanity check"); HeapAccess<>::oop_arraycopy(s, d, src, dst, length); } else { // We have to make sure all elements conform to the destination array Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass(); Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass(); if (stype == bound || stype->is_subtype_of(bound)) { // elements are guaranteed to be subtypes, so no check necessary HeapAccess::oop_arraycopy(s, d, src, dst, length); } else { // slow case: need individual subtype checks // note: don't use obj_at_put below because it includes a redundant store check if (!HeapAccess::oop_arraycopy(s, d, src, dst, length)) { THROW(vmSymbols::java_lang_ArrayStoreException()); } } } } void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS) { assert(s->is_objArray(), "must be obj array"); if (!d->is_objArray()) { THROW(vmSymbols::java_lang_ArrayStoreException()); } // Check is all offsets and lengths are non negative if (src_pos < 0 || dst_pos < 0 || length < 0) { THROW(vmSymbols::java_lang_ArrayIndexOutOfBoundsException()); } // Check if the ranges are valid if ( (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) || (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length()) ) { THROW(vmSymbols::java_lang_ArrayIndexOutOfBoundsException()); } // Special case. Boundary cases must be checked first // This allows the following call: copy_array(s, s.length(), d.length(), 0). // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(), // points to the right of the last element. if (length==0) { return; } if (UseCompressedOops) { narrowOop* const src = objArrayOop(s)->obj_at_addr(src_pos); narrowOop* const dst = objArrayOop(d)->obj_at_addr(dst_pos); do_copy(s, src, d, dst, length, CHECK); } else { oop* const src = objArrayOop(s)->obj_at_addr(src_pos); oop* const dst = objArrayOop(d)->obj_at_addr(dst_pos); do_copy (s, src, d, dst, length, CHECK); } } Klass* ObjArrayKlass::array_klass_impl(bool or_null, int n, TRAPS) { assert(dimension() <= n, "check order of chain"); int dim = dimension(); if (dim == n) return this; // lock-free read needs acquire semantics if (higher_dimension_acquire() == NULL) { if (or_null) return NULL; ResourceMark rm; JavaThread *jt = (JavaThread *)THREAD; { MutexLocker mc(Compile_lock, THREAD); // for vtables // Ensure atomic creation of higher dimensions MutexLocker mu(MultiArray_lock, THREAD); // Check if another thread beat us if (higher_dimension() == NULL) { // Create multi-dim klass object and link them together Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), dim + 1, this, CHECK_NULL); ObjArrayKlass* ak = ObjArrayKlass::cast(k); ak->set_lower_dimension(this); // use 'release' to pair with lock-free load release_set_higher_dimension(ak); assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass"); } } } else { CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); } ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension()); if (or_null) { return ak->array_klass_or_null(n); } return ak->array_klass(n, THREAD); } Klass* ObjArrayKlass::array_klass_impl(bool or_null, TRAPS) { return array_klass_impl(or_null, dimension() + 1, THREAD); } bool ObjArrayKlass::can_be_primary_super_slow() const { if (!bottom_klass()->can_be_primary_super()) // array of interfaces return false; else return Klass::can_be_primary_super_slow(); } GrowableArray* ObjArrayKlass::compute_secondary_supers(int num_extra_slots) { // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... }; Array* elem_supers = element_klass()->secondary_supers(); int num_elem_supers = elem_supers == NULL ? 0 : elem_supers->length(); int num_secondaries = num_extra_slots + 2 + num_elem_supers; if (num_secondaries == 2) { // Must share this for correct bootstrapping! set_secondary_supers(Universe::the_array_interfaces_array()); return NULL; } else { GrowableArray* secondaries = new GrowableArray(num_elem_supers+2); secondaries->push(SystemDictionary::Cloneable_klass()); secondaries->push(SystemDictionary::Serializable_klass()); for (int i = 0; i < num_elem_supers; i++) { Klass* elem_super = (Klass*) elem_supers->at(i); Klass* array_super = elem_super->array_klass_or_null(); assert(array_super != NULL, "must already have been created"); secondaries->push(array_super); } return secondaries; } } bool ObjArrayKlass::compute_is_subtype_of(Klass* k) { if (!k->is_objArray_klass()) return ArrayKlass::compute_is_subtype_of(k); ObjArrayKlass* oak = ObjArrayKlass::cast(k); return element_klass()->is_subtype_of(oak->element_klass()); } void ObjArrayKlass::initialize(TRAPS) { bottom_klass()->initialize(THREAD); // dispatches to either InstanceKlass or TypeArrayKlass } void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) { ArrayKlass::metaspace_pointers_do(it); it->push(&_element_klass); it->push(&_bottom_klass); } // JVM support jint ObjArrayKlass::compute_modifier_flags(TRAPS) const { // The modifier for an objectArray is the same as its element if (element_klass() == NULL) { assert(Universe::is_bootstrapping(), "partial objArray only at startup"); return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC; } // Return the flags of the bottom element type. jint element_flags = bottom_klass()->compute_modifier_flags(CHECK_0); return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED)) | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL); } ModuleEntry* ObjArrayKlass::module() const { assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass"); // The array is defined in the module of its bottom class return bottom_klass()->module(); } PackageEntry* ObjArrayKlass::package() const { assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass"); return bottom_klass()->package(); } // Printing void ObjArrayKlass::print_on(outputStream* st) const { #ifndef PRODUCT Klass::print_on(st); st->print(" - instance klass: "); element_klass()->print_value_on(st); st->cr(); #endif //PRODUCT } void ObjArrayKlass::print_value_on(outputStream* st) const { assert(is_klass(), "must be klass"); element_klass()->print_value_on(st); st->print("[]"); } #ifndef PRODUCT void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) { ArrayKlass::oop_print_on(obj, st); assert(obj->is_objArray(), "must be objArray"); objArrayOop oa = objArrayOop(obj); int print_len = MIN2((intx) oa->length(), MaxElementPrintSize); for(int index = 0; index < print_len; index++) { st->print(" - %3d : ", index); oa->obj_at(index)->print_value_on(st); st->cr(); } int remaining = oa->length() - print_len; if (remaining > 0) { st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining); } } #endif //PRODUCT void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) { assert(obj->is_objArray(), "must be objArray"); st->print("a "); element_klass()->print_value_on(st); int len = objArrayOop(obj)->length(); st->print("[%d] ", len); obj->print_address_on(st); } const char* ObjArrayKlass::internal_name() const { return external_name(); } // Verification void ObjArrayKlass::verify_on(outputStream* st) { ArrayKlass::verify_on(st); guarantee(element_klass()->is_klass(), "should be klass"); guarantee(bottom_klass()->is_klass(), "should be klass"); Klass* bk = bottom_klass(); guarantee(bk->is_instance_klass() || bk->is_typeArray_klass(), "invalid bottom klass"); } void ObjArrayKlass::oop_verify_on(oop obj, outputStream* st) { ArrayKlass::oop_verify_on(obj, st); guarantee(obj->is_objArray(), "must be objArray"); objArrayOop oa = objArrayOop(obj); for(int index = 0; index < oa->length(); index++) { guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop"); } }