Mercurial > hg > truffle
diff src/share/vm/oops/instanceKlass.cpp @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
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date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | 52fed2ec0afb 2c106685d6d0 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/oops/instanceKlass.cpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,2585 @@ +/* + * Copyright 1997-2007 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/_instanceKlass.cpp.incl" + +bool instanceKlass::should_be_initialized() const { + return !is_initialized(); +} + +klassVtable* instanceKlass::vtable() const { + return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size()); +} + +klassItable* instanceKlass::itable() const { + return new klassItable(as_klassOop()); +} + +void instanceKlass::eager_initialize(Thread *thread) { + if (!EagerInitialization) return; + + if (this->is_not_initialized()) { + // abort if the the class has a class initializer + if (this->class_initializer() != NULL) return; + + // abort if it is java.lang.Object (initialization is handled in genesis) + klassOop super = this->super(); + if (super == NULL) return; + + // abort if the super class should be initialized + if (!instanceKlass::cast(super)->is_initialized()) return; + + // call body to expose the this pointer + instanceKlassHandle this_oop(thread, this->as_klassOop()); + eager_initialize_impl(this_oop); + } +} + + +void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) { + EXCEPTION_MARK; + ObjectLocker ol(this_oop, THREAD); + + // abort if someone beat us to the initialization + if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized() + + ClassState old_state = this_oop->_init_state; + link_class_impl(this_oop, true, THREAD); + if (HAS_PENDING_EXCEPTION) { + CLEAR_PENDING_EXCEPTION; + // Abort if linking the class throws an exception. + + // Use a test to avoid redundantly resetting the state if there's + // no change. Set_init_state() asserts that state changes make + // progress, whereas here we might just be spinning in place. + if( old_state != this_oop->_init_state ) + this_oop->set_init_state (old_state); + } else { + // linking successfull, mark class as initialized + this_oop->set_init_state (fully_initialized); + // trace + if (TraceClassInitialization) { + ResourceMark rm(THREAD); + tty->print_cr("[Initialized %s without side effects]", this_oop->external_name()); + } + } +} + + +// See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization +// process. The step comments refers to the procedure described in that section. +// Note: implementation moved to static method to expose the this pointer. +void instanceKlass::initialize(TRAPS) { + if (this->should_be_initialized()) { + HandleMark hm(THREAD); + instanceKlassHandle this_oop(THREAD, this->as_klassOop()); + initialize_impl(this_oop, CHECK); + // Note: at this point the class may be initialized + // OR it may be in the state of being initialized + // in case of recursive initialization! + } else { + assert(is_initialized(), "sanity check"); + } +} + + +bool instanceKlass::verify_code( + instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) { + // 1) Verify the bytecodes + Verifier::Mode mode = + throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; + return Verifier::verify(this_oop, mode, CHECK_false); +} + + +// Used exclusively by the shared spaces dump mechanism to prevent +// classes mapped into the shared regions in new VMs from appearing linked. + +void instanceKlass::unlink_class() { + assert(is_linked(), "must be linked"); + _init_state = loaded; +} + +void instanceKlass::link_class(TRAPS) { + assert(is_loaded(), "must be loaded"); + if (!is_linked()) { + instanceKlassHandle this_oop(THREAD, this->as_klassOop()); + link_class_impl(this_oop, true, CHECK); + } +} + +// Called to verify that a class can link during initialization, without +// throwing a VerifyError. +bool instanceKlass::link_class_or_fail(TRAPS) { + assert(is_loaded(), "must be loaded"); + if (!is_linked()) { + instanceKlassHandle this_oop(THREAD, this->as_klassOop()); + link_class_impl(this_oop, false, CHECK_false); + } + return is_linked(); +} + +bool instanceKlass::link_class_impl( + instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) { + // check for error state + if (this_oop->is_in_error_state()) { + ResourceMark rm(THREAD); + THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), + this_oop->external_name(), false); + } + // return if already verified + if (this_oop->is_linked()) { + return true; + } + + // Timing + // timer handles recursion + assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); + JavaThread* jt = (JavaThread*)THREAD; + PerfTraceTimedEvent vmtimer(ClassLoader::perf_class_link_time(), + ClassLoader::perf_classes_linked(), + jt->get_thread_stat()->class_link_recursion_count_addr()); + + // link super class before linking this class + instanceKlassHandle super(THREAD, this_oop->super()); + if (super.not_null()) { + if (super->is_interface()) { // check if super class is an interface + ResourceMark rm(THREAD); + Exceptions::fthrow( + THREAD_AND_LOCATION, + vmSymbolHandles::java_lang_IncompatibleClassChangeError(), + "class %s has interface %s as super class", + this_oop->external_name(), + super->external_name() + ); + return false; + } + + link_class_impl(super, throw_verifyerror, CHECK_false); + } + + // link all interfaces implemented by this class before linking this class + objArrayHandle interfaces (THREAD, this_oop->local_interfaces()); + int num_interfaces = interfaces->length(); + for (int index = 0; index < num_interfaces; index++) { + HandleMark hm(THREAD); + instanceKlassHandle ih(THREAD, klassOop(interfaces->obj_at(index))); + link_class_impl(ih, throw_verifyerror, CHECK_false); + } + + // in case the class is linked in the process of linking its superclasses + if (this_oop->is_linked()) { + return true; + } + + // verification & rewriting + { + ObjectLocker ol(this_oop, THREAD); + // rewritten will have been set if loader constraint error found + // on an earlier link attempt + // don't verify or rewrite if already rewritten + if (!this_oop->is_linked()) { + if (!this_oop->is_rewritten()) { + { + assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); + JavaThread* jt = (JavaThread*)THREAD; + // Timer includes any side effects of class verification (resolution, + // etc), but not recursive entry into verify_code(). + PerfTraceTime timer(ClassLoader::perf_class_verify_time(), + jt->get_thread_stat()->class_verify_recursion_count_addr()); + bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD); + if (!verify_ok) { + return false; + } + } + + // Just in case a side-effect of verify linked this class already + // (which can sometimes happen since the verifier loads classes + // using custom class loaders, which are free to initialize things) + if (this_oop->is_linked()) { + return true; + } + + // also sets rewritten + this_oop->rewrite_class(CHECK_false); + } + + // Initialize the vtable and interface table after + // methods have been rewritten since rewrite may + // fabricate new methodOops. + // also does loader constraint checking + if (!this_oop()->is_shared()) { + ResourceMark rm(THREAD); + this_oop->vtable()->initialize_vtable(true, CHECK_false); + this_oop->itable()->initialize_itable(true, CHECK_false); + } +#ifdef ASSERT + else { + ResourceMark rm(THREAD); + this_oop->vtable()->verify(tty, true); + // In case itable verification is ever added. + // this_oop->itable()->verify(tty, true); + } +#endif + this_oop->set_init_state(linked); + if (JvmtiExport::should_post_class_prepare()) { + Thread *thread = THREAD; + assert(thread->is_Java_thread(), "thread->is_Java_thread()"); + JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop()); + } + } + } + return true; +} + + +// Rewrite the byte codes of all of the methods of a class. +// Three cases: +// During the link of a newly loaded class. +// During the preloading of classes to be written to the shared spaces. +// - Rewrite the methods and update the method entry points. +// +// During the link of a class in the shared spaces. +// - The methods were already rewritten, update the metho entry points. +// +// The rewriter must be called exactly once. Rewriting must happen after +// verification but before the first method of the class is executed. + +void instanceKlass::rewrite_class(TRAPS) { + assert(is_loaded(), "must be loaded"); + instanceKlassHandle this_oop(THREAD, this->as_klassOop()); + if (this_oop->is_rewritten()) { + assert(this_oop()->is_shared(), "rewriting an unshared class?"); + return; + } + Rewriter::rewrite(this_oop, CHECK); // No exception can happen here + this_oop->set_rewritten(); +} + + +void instanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) { + // Make sure klass is linked (verified) before initialization + // A class could already be verified, since it has been reflected upon. + this_oop->link_class(CHECK); + + // refer to the JVM book page 47 for description of steps + // Step 1 + { ObjectLocker ol(this_oop, THREAD); + + Thread *self = THREAD; // it's passed the current thread + + // Step 2 + // If we were to use wait() instead of waitInterruptibly() then + // we might end up throwing IE from link/symbol resolution sites + // that aren't expected to throw. This would wreak havoc. See 6320309. + while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) { + ol.waitUninterruptibly(CHECK); + } + + // Step 3 + if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) + return; + + // Step 4 + if (this_oop->is_initialized()) + return; + + // Step 5 + if (this_oop->is_in_error_state()) { + ResourceMark rm(THREAD); + const char* desc = "Could not initialize class "; + const char* className = this_oop->external_name(); + size_t msglen = strlen(desc) + strlen(className) + 1; + char* message = NEW_C_HEAP_ARRAY(char, msglen); + if (NULL == message) { + // Out of memory: can't create detailed error message + THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); + } else { + jio_snprintf(message, msglen, "%s%s", desc, className); + THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); + } + } + + // Step 6 + this_oop->set_init_state(being_initialized); + this_oop->set_init_thread(self); + } + + // Step 7 + klassOop super_klass = this_oop->super(); + if (super_klass != NULL && !this_oop->is_interface() && Klass::cast(super_klass)->should_be_initialized()) { + Klass::cast(super_klass)->initialize(THREAD); + + if (HAS_PENDING_EXCEPTION) { + Handle e(THREAD, PENDING_EXCEPTION); + CLEAR_PENDING_EXCEPTION; + { + EXCEPTION_MARK; + this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads + CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below + } + THROW_OOP(e()); + } + } + + // Step 8 + { + assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); + JavaThread* jt = (JavaThread*)THREAD; + // Timer includes any side effects of class initialization (resolution, + // etc), but not recursive entry into call_class_initializer(). + PerfTraceTimedEvent timer(ClassLoader::perf_class_init_time(), + ClassLoader::perf_classes_inited(), + jt->get_thread_stat()->class_init_recursion_count_addr()); + this_oop->call_class_initializer(THREAD); + } + + // Step 9 + if (!HAS_PENDING_EXCEPTION) { + this_oop->set_initialization_state_and_notify(fully_initialized, CHECK); + { ResourceMark rm(THREAD); + debug_only(this_oop->vtable()->verify(tty, true);) + } + } + else { + // Step 10 and 11 + Handle e(THREAD, PENDING_EXCEPTION); + CLEAR_PENDING_EXCEPTION; + { + EXCEPTION_MARK; + this_oop->set_initialization_state_and_notify(initialization_error, THREAD); + CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below + } + if (e->is_a(SystemDictionary::error_klass())) { + THROW_OOP(e()); + } else { + JavaCallArguments args(e); + THROW_ARG(vmSymbolHandles::java_lang_ExceptionInInitializerError(), + vmSymbolHandles::throwable_void_signature(), + &args); + } + } +} + + +// Note: implementation moved to static method to expose the this pointer. +void instanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { + instanceKlassHandle kh(THREAD, this->as_klassOop()); + set_initialization_state_and_notify_impl(kh, state, CHECK); +} + +void instanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) { + ObjectLocker ol(this_oop, THREAD); + this_oop->set_init_state(state); + ol.notify_all(CHECK); +} + +void instanceKlass::add_implementor(klassOop k) { + assert(Compile_lock->owned_by_self(), ""); + // Filter out my subinterfaces. + // (Note: Interfaces are never on the subklass list.) + if (instanceKlass::cast(k)->is_interface()) return; + + // Filter out subclasses whose supers already implement me. + // (Note: CHA must walk subclasses of direct implementors + // in order to locate indirect implementors.) + klassOop sk = instanceKlass::cast(k)->super(); + if (sk != NULL && instanceKlass::cast(sk)->implements_interface(as_klassOop())) + // We only need to check one immediate superclass, since the + // implements_interface query looks at transitive_interfaces. + // Any supers of the super have the same (or fewer) transitive_interfaces. + return; + + // Update number of implementors + int i = _nof_implementors++; + + // Record this implementor, if there are not too many already + if (i < implementors_limit) { + assert(_implementors[i] == NULL, "should be exactly one implementor"); + oop_store_without_check((oop*)&_implementors[i], k); + } else if (i == implementors_limit) { + // clear out the list on first overflow + for (int i2 = 0; i2 < implementors_limit; i2++) + oop_store_without_check((oop*)&_implementors[i2], NULL); + } + + // The implementor also implements the transitive_interfaces + for (int index = 0; index < local_interfaces()->length(); index++) { + instanceKlass::cast(klassOop(local_interfaces()->obj_at(index)))->add_implementor(k); + } +} + +void instanceKlass::init_implementor() { + for (int i = 0; i < implementors_limit; i++) + oop_store_without_check((oop*)&_implementors[i], NULL); + _nof_implementors = 0; +} + + +void instanceKlass::process_interfaces(Thread *thread) { + // link this class into the implementors list of every interface it implements + KlassHandle this_as_oop (thread, this->as_klassOop()); + for (int i = local_interfaces()->length() - 1; i >= 0; i--) { + assert(local_interfaces()->obj_at(i)->is_klass(), "must be a klass"); + instanceKlass* interf = instanceKlass::cast(klassOop(local_interfaces()->obj_at(i))); + assert(interf->is_interface(), "expected interface"); + interf->add_implementor(this_as_oop()); + } +} + +bool instanceKlass::can_be_primary_super_slow() const { + if (is_interface()) + return false; + else + return Klass::can_be_primary_super_slow(); +} + +objArrayOop instanceKlass::compute_secondary_supers(int num_extra_slots, TRAPS) { + // The secondaries are the implemented interfaces. + instanceKlass* ik = instanceKlass::cast(as_klassOop()); + objArrayHandle interfaces (THREAD, ik->transitive_interfaces()); + int num_secondaries = num_extra_slots + interfaces->length(); + if (num_secondaries == 0) { + return Universe::the_empty_system_obj_array(); + } else if (num_extra_slots == 0) { + return interfaces(); + } else { + // a mix of both + objArrayOop secondaries = oopFactory::new_system_objArray(num_secondaries, CHECK_NULL); + for (int i = 0; i < interfaces->length(); i++) { + secondaries->obj_at_put(num_extra_slots+i, interfaces->obj_at(i)); + } + return secondaries; + } +} + +bool instanceKlass::compute_is_subtype_of(klassOop k) { + if (Klass::cast(k)->is_interface()) { + return implements_interface(k); + } else { + return Klass::compute_is_subtype_of(k); + } +} + +bool instanceKlass::implements_interface(klassOop k) const { + if (as_klassOop() == k) return true; + assert(Klass::cast(k)->is_interface(), "should be an interface class"); + for (int i = 0; i < transitive_interfaces()->length(); i++) { + if (transitive_interfaces()->obj_at(i) == k) { + return true; + } + } + return false; +} + +objArrayOop instanceKlass::allocate_objArray(int n, int length, TRAPS) { + if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); + if (length > arrayOopDesc::max_array_length(T_OBJECT)) { + THROW_OOP_0(Universe::out_of_memory_error_array_size()); + } + int size = objArrayOopDesc::object_size(length); + klassOop ak = array_klass(n, CHECK_NULL); + KlassHandle h_ak (THREAD, ak); + objArrayOop o = + (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); + return o; +} + +instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) { + if (TraceFinalizerRegistration) { + tty->print("Registered "); + i->print_value_on(tty); + tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i); + } + instanceHandle h_i(THREAD, i); + // Pass the handle as argument, JavaCalls::call expects oop as jobjects + JavaValue result(T_VOID); + JavaCallArguments args(h_i); + methodHandle mh (THREAD, Universe::finalizer_register_method()); + JavaCalls::call(&result, mh, &args, CHECK_NULL); + return h_i(); +} + +instanceOop instanceKlass::allocate_instance(TRAPS) { + bool has_finalizer_flag = has_finalizer(); // Query before possible GC + int size = size_helper(); // Query before forming handle. + + KlassHandle h_k(THREAD, as_klassOop()); + + instanceOop i; + + i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); + if (has_finalizer_flag && !RegisterFinalizersAtInit) { + i = register_finalizer(i, CHECK_NULL); + } + return i; +} + +instanceOop instanceKlass::allocate_permanent_instance(TRAPS) { + // Finalizer registration occurs in the Object.<init> constructor + // and constructors normally aren't run when allocating perm + // instances so simply disallow finalizable perm objects. This can + // be relaxed if a need for it is found. + assert(!has_finalizer(), "perm objects not allowed to have finalizers"); + int size = size_helper(); // Query before forming handle. + KlassHandle h_k(THREAD, as_klassOop()); + instanceOop i = (instanceOop) + CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL); + return i; +} + +void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { + if (is_interface() || is_abstract()) { + ResourceMark rm(THREAD); + THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() + : vmSymbols::java_lang_InstantiationException(), external_name()); + } + if (as_klassOop() == SystemDictionary::class_klass()) { + ResourceMark rm(THREAD); + THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() + : vmSymbols::java_lang_IllegalAccessException(), external_name()); + } +} + +klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { + instanceKlassHandle this_oop(THREAD, as_klassOop()); + return array_klass_impl(this_oop, or_null, n, THREAD); +} + +klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) { + if (this_oop->array_klasses() == NULL) { + if (or_null) return NULL; + + ResourceMark rm; + JavaThread *jt = (JavaThread *)THREAD; + { + // Atomic creation of array_klasses + MutexLocker mc(Compile_lock, THREAD); // for vtables + MutexLocker ma(MultiArray_lock, THREAD); + + // Check if update has already taken place + if (this_oop->array_klasses() == NULL) { + objArrayKlassKlass* oakk = + (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part(); + + klassOop k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL); + this_oop->set_array_klasses(k); + } + } + } + // _this will always be set at this point + objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part(); + if (or_null) { + return oak->array_klass_or_null(n); + } + return oak->array_klass(n, CHECK_NULL); +} + +klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) { + return array_klass_impl(or_null, 1, THREAD); +} + +void instanceKlass::call_class_initializer(TRAPS) { + instanceKlassHandle ik (THREAD, as_klassOop()); + call_class_initializer_impl(ik, THREAD); +} + +static int call_class_initializer_impl_counter = 0; // for debugging + +methodOop instanceKlass::class_initializer() { + return find_method(vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); +} + +void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) { + methodHandle h_method(THREAD, this_oop->class_initializer()); + assert(!this_oop->is_initialized(), "we cannot initialize twice"); + if (TraceClassInitialization) { + tty->print("%d Initializing ", call_class_initializer_impl_counter++); + this_oop->name()->print_value(); + tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop()); + } + if (h_method() != NULL) { + JavaCallArguments args; // No arguments + JavaValue result(T_VOID); + JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) + } +} + + +void instanceKlass::mask_for(methodHandle method, int bci, + InterpreterOopMap* entry_for) { + // Dirty read, then double-check under a lock. + if (_oop_map_cache == NULL) { + // Otherwise, allocate a new one. + MutexLocker x(OopMapCacheAlloc_lock); + // First time use. Allocate a cache in C heap + if (_oop_map_cache == NULL) { + _oop_map_cache = new OopMapCache(); + } + } + // _oop_map_cache is constant after init; lookup below does is own locking. + _oop_map_cache->lookup(method, bci, entry_for); +} + + +bool instanceKlass::find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const { + const int n = fields()->length(); + for (int i = 0; i < n; i += next_offset ) { + int name_index = fields()->ushort_at(i + name_index_offset); + int sig_index = fields()->ushort_at(i + signature_index_offset); + symbolOop f_name = constants()->symbol_at(name_index); + symbolOop f_sig = constants()->symbol_at(sig_index); + if (f_name == name && f_sig == sig) { + fd->initialize(as_klassOop(), i); + return true; + } + } + return false; +} + + +void instanceKlass::field_names_and_sigs_iterate(OopClosure* closure) { + const int n = fields()->length(); + for (int i = 0; i < n; i += next_offset ) { + int name_index = fields()->ushort_at(i + name_index_offset); + symbolOop name = constants()->symbol_at(name_index); + closure->do_oop((oop*)&name); + + int sig_index = fields()->ushort_at(i + signature_index_offset); + symbolOop sig = constants()->symbol_at(sig_index); + closure->do_oop((oop*)&sig); + } +} + + +klassOop instanceKlass::find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const { + const int n = local_interfaces()->length(); + for (int i = 0; i < n; i++) { + klassOop intf1 = klassOop(local_interfaces()->obj_at(i)); + assert(Klass::cast(intf1)->is_interface(), "just checking type"); + // search for field in current interface + if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { + assert(fd->is_static(), "interface field must be static"); + return intf1; + } + // search for field in direct superinterfaces + klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd); + if (intf2 != NULL) return intf2; + } + // otherwise field lookup fails + return NULL; +} + + +klassOop instanceKlass::find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const { + // search order according to newest JVM spec (5.4.3.2, p.167). + // 1) search for field in current klass + if (find_local_field(name, sig, fd)) { + return as_klassOop(); + } + // 2) search for field recursively in direct superinterfaces + { klassOop intf = find_interface_field(name, sig, fd); + if (intf != NULL) return intf; + } + // 3) apply field lookup recursively if superclass exists + { klassOop supr = super(); + if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd); + } + // 4) otherwise field lookup fails + return NULL; +} + + +klassOop instanceKlass::find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const { + // search order according to newest JVM spec (5.4.3.2, p.167). + // 1) search for field in current klass + if (find_local_field(name, sig, fd)) { + if (fd->is_static() == is_static) return as_klassOop(); + } + // 2) search for field recursively in direct superinterfaces + if (is_static) { + klassOop intf = find_interface_field(name, sig, fd); + if (intf != NULL) return intf; + } + // 3) apply field lookup recursively if superclass exists + { klassOop supr = super(); + if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd); + } + // 4) otherwise field lookup fails + return NULL; +} + + +bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { + int length = fields()->length(); + for (int i = 0; i < length; i += next_offset) { + if (offset_from_fields( i ) == offset) { + fd->initialize(as_klassOop(), i); + if (fd->is_static() == is_static) return true; + } + } + return false; +} + + +bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { + klassOop klass = as_klassOop(); + while (klass != NULL) { + if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { + return true; + } + klass = Klass::cast(klass)->super(); + } + return false; +} + + +void instanceKlass::methods_do(void f(methodOop method)) { + int len = methods()->length(); + for (int index = 0; index < len; index++) { + methodOop m = methodOop(methods()->obj_at(index)); + assert(m->is_method(), "must be method"); + f(m); + } +} + +void instanceKlass::do_local_static_fields(FieldClosure* cl) { + fieldDescriptor fd; + int length = fields()->length(); + for (int i = 0; i < length; i += next_offset) { + fd.initialize(as_klassOop(), i); + if (fd.is_static()) cl->do_field(&fd); + } +} + + +void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) { + instanceKlassHandle h_this(THREAD, as_klassOop()); + do_local_static_fields_impl(h_this, f, CHECK); +} + + +void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) { + fieldDescriptor fd; + int length = this_oop->fields()->length(); + for (int i = 0; i < length; i += next_offset) { + fd.initialize(this_oop(), i); + if (fd.is_static()) { f(&fd, CHECK); } // Do NOT remove {}! (CHECK macro expands into several statements) + } +} + + +void instanceKlass::do_nonstatic_fields(FieldClosure* cl) { + fieldDescriptor fd; + instanceKlass* super = superklass(); + if (super != NULL) { + super->do_nonstatic_fields(cl); + } + int length = fields()->length(); + for (int i = 0; i < length; i += next_offset) { + fd.initialize(as_klassOop(), i); + if (!(fd.is_static())) cl->do_field(&fd); + } +} + + +void instanceKlass::array_klasses_do(void f(klassOop k)) { + if (array_klasses() != NULL) + arrayKlass::cast(array_klasses())->array_klasses_do(f); +} + + +void instanceKlass::with_array_klasses_do(void f(klassOop k)) { + f(as_klassOop()); + array_klasses_do(f); +} + +#ifdef ASSERT +static int linear_search(objArrayOop methods, symbolOop name, symbolOop signature) { + int len = methods->length(); + for (int index = 0; index < len; index++) { + methodOop m = (methodOop)(methods->obj_at(index)); + assert(m->is_method(), "must be method"); + if (m->signature() == signature && m->name() == name) { + return index; + } + } + return -1; +} +#endif + +methodOop instanceKlass::find_method(symbolOop name, symbolOop signature) const { + return instanceKlass::find_method(methods(), name, signature); +} + +methodOop instanceKlass::find_method(objArrayOop methods, symbolOop name, symbolOop signature) { + int len = methods->length(); + // methods are sorted, so do binary search + int l = 0; + int h = len - 1; + while (l <= h) { + int mid = (l + h) >> 1; + methodOop m = (methodOop)methods->obj_at(mid); + assert(m->is_method(), "must be method"); + int res = m->name()->fast_compare(name); + if (res == 0) { + // found matching name; do linear search to find matching signature + // first, quick check for common case + if (m->signature() == signature) return m; + // search downwards through overloaded methods + int i; + for (i = mid - 1; i >= l; i--) { + methodOop m = (methodOop)methods->obj_at(i); + assert(m->is_method(), "must be method"); + if (m->name() != name) break; + if (m->signature() == signature) return m; + } + // search upwards + for (i = mid + 1; i <= h; i++) { + methodOop m = (methodOop)methods->obj_at(i); + assert(m->is_method(), "must be method"); + if (m->name() != name) break; + if (m->signature() == signature) return m; + } + // not found +#ifdef ASSERT + int index = linear_search(methods, name, signature); + if (index != -1) fatal1("binary search bug: should have found entry %d", index); +#endif + return NULL; + } else if (res < 0) { + l = mid + 1; + } else { + h = mid - 1; + } + } +#ifdef ASSERT + int index = linear_search(methods, name, signature); + if (index != -1) fatal1("binary search bug: should have found entry %d", index); +#endif + return NULL; +} + +methodOop instanceKlass::uncached_lookup_method(symbolOop name, symbolOop signature) const { + klassOop klass = as_klassOop(); + while (klass != NULL) { + methodOop method = instanceKlass::cast(klass)->find_method(name, signature); + if (method != NULL) return method; + klass = instanceKlass::cast(klass)->super(); + } + return NULL; +} + +// lookup a method in all the interfaces that this class implements +methodOop instanceKlass::lookup_method_in_all_interfaces(symbolOop name, + symbolOop signature) const { + objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces(); + int num_ifs = all_ifs->length(); + instanceKlass *ik = NULL; + for (int i = 0; i < num_ifs; i++) { + ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i))); + methodOop m = ik->lookup_method(name, signature); + if (m != NULL) { + return m; + } + } + return NULL; +} + +/* jni_id_for_impl for jfieldIds only */ +JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) { + MutexLocker ml(JfieldIdCreation_lock); + // Retry lookup after we got the lock + JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset); + if (probe == NULL) { + // Slow case, allocate new static field identifier + probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids()); + this_oop->set_jni_ids(probe); + } + return probe; +} + + +/* jni_id_for for jfieldIds only */ +JNIid* instanceKlass::jni_id_for(int offset) { + JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); + if (probe == NULL) { + probe = jni_id_for_impl(this->as_klassOop(), offset); + } + return probe; +} + + +// Lookup or create a jmethodID. +// This code can be called by the VM thread. For this reason it is critical that +// there are no blocking operations (safepoints) while the lock is held -- or a +// deadlock can occur. +jmethodID instanceKlass::jmethod_id_for_impl(instanceKlassHandle ik_h, methodHandle method_h) { + size_t idnum = (size_t)method_h->method_idnum(); + jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); + size_t length = 0; + jmethodID id = NULL; + // array length stored in first element, other elements offset by one + if (jmeths == NULL || // If there is no jmethodID array, + (length = (size_t)jmeths[0]) <= idnum || // or if it is too short, + (id = jmeths[idnum+1]) == NULL) { // or if this jmethodID isn't allocated + + // Do all the safepointing things (allocations) before grabbing the lock. + // These allocations will have to be freed if they are unused. + + // Allocate a new array of methods. + jmethodID* to_dealloc_jmeths = NULL; + jmethodID* new_jmeths = NULL; + if (length <= idnum) { + // A new array will be needed (unless some other thread beats us to it) + size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); + new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1); + memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); + new_jmeths[0] =(jmethodID)size; // array size held in the first element + } + + // Allocate a new method ID. + jmethodID to_dealloc_id = NULL; + jmethodID new_id = NULL; + if (method_h->is_old() && !method_h->is_obsolete()) { + // The method passed in is old (but not obsolete), we need to use the current version + methodOop current_method = ik_h->method_with_idnum((int)idnum); + assert(current_method != NULL, "old and but not obsolete, so should exist"); + methodHandle current_method_h(current_method == NULL? method_h() : current_method); + new_id = JNIHandles::make_jmethod_id(current_method_h); + } else { + // It is the current version of the method or an obsolete method, + // use the version passed in + new_id = JNIHandles::make_jmethod_id(method_h); + } + + { + MutexLocker ml(JmethodIdCreation_lock); + + // We must not go to a safepoint while holding this lock. + debug_only(No_Safepoint_Verifier nosafepoints;) + + // Retry lookup after we got the lock + jmeths = ik_h->methods_jmethod_ids_acquire(); + if (jmeths == NULL || (length = (size_t)jmeths[0]) <= idnum) { + if (jmeths != NULL) { + // We have grown the array: copy the existing entries, and delete the old array + for (size_t index = 0; index < length; index++) { + new_jmeths[index+1] = jmeths[index+1]; + } + to_dealloc_jmeths = jmeths; // using the new jmeths, deallocate the old one + } + ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); + } else { + id = jmeths[idnum+1]; + to_dealloc_jmeths = new_jmeths; // using the old jmeths, deallocate the new one + } + if (id == NULL) { + id = new_id; + jmeths[idnum+1] = id; // install the new method ID + } else { + to_dealloc_id = new_id; // the new id wasn't used, mark it for deallocation + } + } + + // Free up unneeded or no longer needed resources + FreeHeap(to_dealloc_jmeths); + if (to_dealloc_id != NULL) { + JNIHandles::destroy_jmethod_id(to_dealloc_id); + } + } + return id; +} + + +// Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles +jmethodID instanceKlass::jmethod_id_or_null(methodOop method) { + size_t idnum = (size_t)method->method_idnum(); + jmethodID* jmeths = methods_jmethod_ids_acquire(); + size_t length; // length assigned as debugging crumb + jmethodID id = NULL; + if (jmeths != NULL && // If there is a jmethodID array, + (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, + id = jmeths[idnum+1]; // Look up the id (may be NULL) + } + return id; +} + + +// Cache an itable index +void instanceKlass::set_cached_itable_index(size_t idnum, int index) { + int* indices = methods_cached_itable_indices_acquire(); + if (indices == NULL || // If there is no index array, + ((size_t)indices[0]) <= idnum) { // or if it is too short + // Lock before we allocate the array so we don't leak + MutexLocker ml(JNICachedItableIndex_lock); + // Retry lookup after we got the lock + indices = methods_cached_itable_indices_acquire(); + size_t length = 0; + // array length stored in first element, other elements offset by one + if (indices == NULL || (length = (size_t)indices[0]) <= idnum) { + size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); + int* new_indices = NEW_C_HEAP_ARRAY(int, size+1); + // Copy the existing entries, if any + size_t i; + for (i = 0; i < length; i++) { + new_indices[i+1] = indices[i+1]; + } + // Set all the rest to -1 + for (i = length; i < size; i++) { + new_indices[i+1] = -1; + } + if (indices != NULL) { + FreeHeap(indices); // delete any old indices + } + release_set_methods_cached_itable_indices(indices = new_indices); + } + } else { + CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); + } + // This is a cache, if there is a race to set it, it doesn't matter + indices[idnum+1] = index; +} + + +// Retrieve a cached itable index +int instanceKlass::cached_itable_index(size_t idnum) { + int* indices = methods_cached_itable_indices_acquire(); + if (indices != NULL && ((size_t)indices[0]) > idnum) { + // indices exist and are long enough, retrieve possible cached + return indices[idnum+1]; + } + return -1; +} + + +// +// nmethodBucket is used to record dependent nmethods for +// deoptimization. nmethod dependencies are actually <klass, method> +// pairs but we really only care about the klass part for purposes of +// finding nmethods which might need to be deoptimized. Instead of +// recording the method, a count of how many times a particular nmethod +// was recorded is kept. This ensures that any recording errors are +// noticed since an nmethod should be removed as many times are it's +// added. +// +class nmethodBucket { + private: + nmethod* _nmethod; + int _count; + nmethodBucket* _next; + + public: + nmethodBucket(nmethod* nmethod, nmethodBucket* next) { + _nmethod = nmethod; + _next = next; + _count = 1; + } + int count() { return _count; } + int increment() { _count += 1; return _count; } + int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; } + nmethodBucket* next() { return _next; } + void set_next(nmethodBucket* b) { _next = b; } + nmethod* get_nmethod() { return _nmethod; } +}; + + +// +// Walk the list of dependent nmethods searching for nmethods which +// are dependent on the klassOop that was passed in and mark them for +// deoptimization. Returns the number of nmethods found. +// +int instanceKlass::mark_dependent_nmethods(DepChange& changes) { + assert_locked_or_safepoint(CodeCache_lock); + int found = 0; + nmethodBucket* b = _dependencies; + while (b != NULL) { + nmethod* nm = b->get_nmethod(); + // since dependencies aren't removed until an nmethod becomes a zombie, + // the dependency list may contain nmethods which aren't alive. + if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) { + if (TraceDependencies) { + ResourceMark rm; + tty->print_cr("Marked for deoptimization"); + tty->print_cr(" context = %s", this->external_name()); + changes.print(); + nm->print(); + nm->print_dependencies(); + } + nm->mark_for_deoptimization(); + found++; + } + b = b->next(); + } + return found; +} + + +// +// Add an nmethodBucket to the list of dependencies for this nmethod. +// It's possible that an nmethod has multiple dependencies on this klass +// so a count is kept for each bucket to guarantee that creation and +// deletion of dependencies is consistent. +// +void instanceKlass::add_dependent_nmethod(nmethod* nm) { + assert_locked_or_safepoint(CodeCache_lock); + nmethodBucket* b = _dependencies; + nmethodBucket* last = NULL; + while (b != NULL) { + if (nm == b->get_nmethod()) { + b->increment(); + return; + } + b = b->next(); + } + _dependencies = new nmethodBucket(nm, _dependencies); +} + + +// +// Decrement count of the nmethod in the dependency list and remove +// the bucket competely when the count goes to 0. This method must +// find a corresponding bucket otherwise there's a bug in the +// recording of dependecies. +// +void instanceKlass::remove_dependent_nmethod(nmethod* nm) { + assert_locked_or_safepoint(CodeCache_lock); + nmethodBucket* b = _dependencies; + nmethodBucket* last = NULL; + while (b != NULL) { + if (nm == b->get_nmethod()) { + if (b->decrement() == 0) { + if (last == NULL) { + _dependencies = b->next(); + } else { + last->set_next(b->next()); + } + delete b; + } + return; + } + last = b; + b = b->next(); + } +#ifdef ASSERT + tty->print_cr("### %s can't find dependent nmethod:", this->external_name()); + nm->print(); +#endif // ASSERT + ShouldNotReachHere(); +} + + +#ifndef PRODUCT +void instanceKlass::print_dependent_nmethods(bool verbose) { + nmethodBucket* b = _dependencies; + int idx = 0; + while (b != NULL) { + nmethod* nm = b->get_nmethod(); + tty->print("[%d] count=%d { ", idx++, b->count()); + if (!verbose) { + nm->print_on(tty, "nmethod"); + tty->print_cr(" } "); + } else { + nm->print(); + nm->print_dependencies(); + tty->print_cr("--- } "); + } + b = b->next(); + } +} + + +bool instanceKlass::is_dependent_nmethod(nmethod* nm) { + nmethodBucket* b = _dependencies; + while (b != NULL) { + if (nm == b->get_nmethod()) { + return true; + } + b = b->next(); + } + return false; +} +#endif //PRODUCT + + +void instanceKlass::follow_static_fields() { + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + while (start < end) { + if (*start != NULL) { + assert(Universe::heap()->is_in_closed_subset(*start), + "should be in heap"); + MarkSweep::mark_and_push(start); + } + start++; + } +} + +#ifndef SERIALGC +void instanceKlass::follow_static_fields(ParCompactionManager* cm) { + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + while (start < end) { + if (*start != NULL) { + assert(Universe::heap()->is_in(*start), "should be in heap"); + PSParallelCompact::mark_and_push(cm, start); + } + start++; + } +} +#endif // SERIALGC + + +void instanceKlass::adjust_static_fields() { + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + while (start < end) { + MarkSweep::adjust_pointer(start); + start++; + } +} + +#ifndef SERIALGC +void instanceKlass::update_static_fields() { + oop* const start = start_of_static_fields(); + oop* const beg_oop = start; + oop* const end_oop = start + static_oop_field_size(); + for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) { + PSParallelCompact::adjust_pointer(cur_oop); + } +} + +void +instanceKlass::update_static_fields(HeapWord* beg_addr, HeapWord* end_addr) { + oop* const start = start_of_static_fields(); + oop* const beg_oop = MAX2((oop*)beg_addr, start); + oop* const end_oop = MIN2((oop*)end_addr, start + static_oop_field_size()); + for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) { + PSParallelCompact::adjust_pointer(cur_oop); + } +} +#endif // SERIALGC + +void instanceKlass::oop_follow_contents(oop obj) { + assert (obj!=NULL, "can't follow the content of NULL object"); + obj->follow_header(); + OopMapBlock* map = start_of_nonstatic_oop_maps(); + OopMapBlock* end_map = map + nonstatic_oop_map_size(); + while (map < end_map) { + oop* start = obj->obj_field_addr(map->offset()); + oop* end = start + map->length(); + while (start < end) { + if (*start != NULL) { + assert(Universe::heap()->is_in_closed_subset(*start), + "should be in heap"); + MarkSweep::mark_and_push(start); + } + start++; + } + map++; + } +} + +#ifndef SERIALGC +void instanceKlass::oop_follow_contents(ParCompactionManager* cm, + oop obj) { + assert (obj!=NULL, "can't follow the content of NULL object"); + obj->follow_header(cm); + OopMapBlock* map = start_of_nonstatic_oop_maps(); + OopMapBlock* end_map = map + nonstatic_oop_map_size(); + while (map < end_map) { + oop* start = obj->obj_field_addr(map->offset()); + oop* end = start + map->length(); + while (start < end) { + if (*start != NULL) { + assert(Universe::heap()->is_in(*start), "should be in heap"); + PSParallelCompact::mark_and_push(cm, start); + } + start++; + } + map++; + } +} +#endif // SERIALGC + +#define invoke_closure_on(start, closure, nv_suffix) { \ + oop obj = *(start); \ + if (obj != NULL) { \ + assert(Universe::heap()->is_in_closed_subset(obj), "should be in heap"); \ + (closure)->do_oop##nv_suffix(start); \ + } \ +} + +// closure's do_header() method dicates whether the given closure should be +// applied to the klass ptr in the object header. + +#define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ + \ +int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, \ + OopClosureType* closure) { \ + SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \ + /* header */ \ + if (closure->do_header()) { \ + obj->oop_iterate_header(closure); \ + } \ + /* instance variables */ \ + OopMapBlock* map = start_of_nonstatic_oop_maps(); \ + OopMapBlock* const end_map = map + nonstatic_oop_map_size(); \ + const intx field_offset = PrefetchFieldsAhead; \ + if (field_offset > 0) { \ + while (map < end_map) { \ + oop* start = obj->obj_field_addr(map->offset()); \ + oop* const end = start + map->length(); \ + while (start < end) { \ + prefetch_beyond(start, (oop*)end, field_offset, \ + closure->prefetch_style()); \ + SpecializationStats:: \ + record_do_oop_call##nv_suffix(SpecializationStats::ik); \ + invoke_closure_on(start, closure, nv_suffix); \ + start++; \ + } \ + map++; \ + } \ + } else { \ + while (map < end_map) { \ + oop* start = obj->obj_field_addr(map->offset()); \ + oop* const end = start + map->length(); \ + while (start < end) { \ + SpecializationStats:: \ + record_do_oop_call##nv_suffix(SpecializationStats::ik); \ + invoke_closure_on(start, closure, nv_suffix); \ + start++; \ + } \ + map++; \ + } \ + } \ + return size_helper(); \ +} + +#define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \ + \ +int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \ + OopClosureType* closure, \ + MemRegion mr) { \ + SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \ + /* header */ \ + if (closure->do_header()) { \ + obj->oop_iterate_header(closure, mr); \ + } \ + /* instance variables */ \ + OopMapBlock* map = start_of_nonstatic_oop_maps(); \ + OopMapBlock* const end_map = map + nonstatic_oop_map_size(); \ + HeapWord* bot = mr.start(); \ + HeapWord* top = mr.end(); \ + oop* start = obj->obj_field_addr(map->offset()); \ + HeapWord* end = MIN2((HeapWord*)(start + map->length()), top); \ + /* Find the first map entry that extends onto mr. */ \ + while (map < end_map && end <= bot) { \ + map++; \ + start = obj->obj_field_addr(map->offset()); \ + end = MIN2((HeapWord*)(start + map->length()), top); \ + } \ + if (map != end_map) { \ + /* The current map's end is past the start of "mr". Skip up to the first \ + entry on "mr". */ \ + while ((HeapWord*)start < bot) { \ + start++; \ + } \ + const intx field_offset = PrefetchFieldsAhead; \ + for (;;) { \ + if (field_offset > 0) { \ + while ((HeapWord*)start < end) { \ + prefetch_beyond(start, (oop*)end, field_offset, \ + closure->prefetch_style()); \ + invoke_closure_on(start, closure, nv_suffix); \ + start++; \ + } \ + } else { \ + while ((HeapWord*)start < end) { \ + invoke_closure_on(start, closure, nv_suffix); \ + start++; \ + } \ + } \ + /* Go to the next map. */ \ + map++; \ + if (map == end_map) { \ + break; \ + } \ + /* Otherwise, */ \ + start = obj->obj_field_addr(map->offset()); \ + if ((HeapWord*)start >= top) { \ + break; \ + } \ + end = MIN2((HeapWord*)(start + map->length()), top); \ + } \ + } \ + return size_helper(); \ +} + +ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN) +ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DEFN) +ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) +ALL_OOP_OOP_ITERATE_CLOSURES_3(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) + + +void instanceKlass::iterate_static_fields(OopClosure* closure) { + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + while (start < end) { + assert(Universe::heap()->is_in_reserved_or_null(*start), "should be in heap"); + closure->do_oop(start); + start++; + } +} + +void instanceKlass::iterate_static_fields(OopClosure* closure, + MemRegion mr) { + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + // I gather that the the static fields of reference types come first, + // hence the name of "oop_field_size", and that is what makes this safe. + assert((intptr_t)mr.start() == + align_size_up((intptr_t)mr.start(), sizeof(oop)) && + (intptr_t)mr.end() == align_size_up((intptr_t)mr.end(), sizeof(oop)), + "Memregion must be oop-aligned."); + if ((HeapWord*)start < mr.start()) start = (oop*)mr.start(); + if ((HeapWord*)end > mr.end()) end = (oop*)mr.end(); + while (start < end) { + invoke_closure_on(start, closure,_v); + start++; + } +} + + +int instanceKlass::oop_adjust_pointers(oop obj) { + int size = size_helper(); + + // Compute oopmap block range. The common case is nonstatic_oop_map_size == 1. + OopMapBlock* map = start_of_nonstatic_oop_maps(); + OopMapBlock* const end_map = map + nonstatic_oop_map_size(); + // Iterate over oopmap blocks + while (map < end_map) { + // Compute oop range for this block + oop* start = obj->obj_field_addr(map->offset()); + oop* end = start + map->length(); + // Iterate over oops + while (start < end) { + assert(Universe::heap()->is_in_or_null(*start), "should be in heap"); + MarkSweep::adjust_pointer(start); + start++; + } + map++; + } + + obj->adjust_header(); + return size; +} + +#ifndef SERIALGC +void instanceKlass::oop_copy_contents(PSPromotionManager* pm, oop obj) { + assert(!pm->depth_first(), "invariant"); + // Compute oopmap block range. The common case is nonstatic_oop_map_size == 1. + OopMapBlock* start_map = start_of_nonstatic_oop_maps(); + OopMapBlock* map = start_map + nonstatic_oop_map_size(); + + // Iterate over oopmap blocks + while (start_map < map) { + --map; + // Compute oop range for this block + oop* start = obj->obj_field_addr(map->offset()); + oop* curr = start + map->length(); + // Iterate over oops + while (start < curr) { + --curr; + if (PSScavenge::should_scavenge(*curr)) { + assert(Universe::heap()->is_in(*curr), "should be in heap"); + pm->claim_or_forward_breadth(curr); + } + } + } +} + +void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) { + assert(pm->depth_first(), "invariant"); + // Compute oopmap block range. The common case is nonstatic_oop_map_size == 1. + OopMapBlock* start_map = start_of_nonstatic_oop_maps(); + OopMapBlock* map = start_map + nonstatic_oop_map_size(); + + // Iterate over oopmap blocks + while (start_map < map) { + --map; + // Compute oop range for this block + oop* start = obj->obj_field_addr(map->offset()); + oop* curr = start + map->length(); + // Iterate over oops + while (start < curr) { + --curr; + if (PSScavenge::should_scavenge(*curr)) { + assert(Universe::heap()->is_in(*curr), "should be in heap"); + pm->claim_or_forward_depth(curr); + } + } + } +} + +int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) { + // Compute oopmap block range. The common case is nonstatic_oop_map_size==1. + OopMapBlock* map = start_of_nonstatic_oop_maps(); + OopMapBlock* const end_map = map + nonstatic_oop_map_size(); + // Iterate over oopmap blocks + while (map < end_map) { + // Compute oop range for this oopmap block. + oop* const map_start = obj->obj_field_addr(map->offset()); + oop* const beg_oop = map_start; + oop* const end_oop = map_start + map->length(); + for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) { + PSParallelCompact::adjust_pointer(cur_oop); + } + ++map; + } + + return size_helper(); +} + +int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj, + HeapWord* beg_addr, HeapWord* end_addr) { + // Compute oopmap block range. The common case is nonstatic_oop_map_size==1. + OopMapBlock* map = start_of_nonstatic_oop_maps(); + OopMapBlock* const end_map = map + nonstatic_oop_map_size(); + // Iterate over oopmap blocks + while (map < end_map) { + // Compute oop range for this oopmap block. + oop* const map_start = obj->obj_field_addr(map->offset()); + oop* const beg_oop = MAX2((oop*)beg_addr, map_start); + oop* const end_oop = MIN2((oop*)end_addr, map_start + map->length()); + for (oop* cur_oop = beg_oop; cur_oop < end_oop; ++cur_oop) { + PSParallelCompact::adjust_pointer(cur_oop); + } + ++map; + } + + return size_helper(); +} + +void instanceKlass::copy_static_fields(PSPromotionManager* pm) { + assert(!pm->depth_first(), "invariant"); + // Compute oop range + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + // Iterate over oops + while (start < end) { + if (PSScavenge::should_scavenge(*start)) { + assert(Universe::heap()->is_in(*start), "should be in heap"); + pm->claim_or_forward_breadth(start); + } + start++; + } +} + +void instanceKlass::push_static_fields(PSPromotionManager* pm) { + assert(pm->depth_first(), "invariant"); + // Compute oop range + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + // Iterate over oops + while (start < end) { + if (PSScavenge::should_scavenge(*start)) { + assert(Universe::heap()->is_in(*start), "should be in heap"); + pm->claim_or_forward_depth(start); + } + start++; + } +} + +void instanceKlass::copy_static_fields(ParCompactionManager* cm) { + // Compute oop range + oop* start = start_of_static_fields(); + oop* end = start + static_oop_field_size(); + // Iterate over oops + while (start < end) { + if (*start != NULL) { + assert(Universe::heap()->is_in(*start), "should be in heap"); + // *start = (oop) cm->summary_data()->calc_new_pointer(*start); + PSParallelCompact::adjust_pointer(start); + } + start++; + } +} +#endif // SERIALGC + +// This klass is alive but the implementor link is not followed/updated. +// Subklass and sibling links are handled by Klass::follow_weak_klass_links + +void instanceKlass::follow_weak_klass_links( + BoolObjectClosure* is_alive, OopClosure* keep_alive) { + assert(is_alive->do_object_b(as_klassOop()), "this oop should be live"); + if (ClassUnloading) { + for (int i = 0; i < implementors_limit; i++) { + klassOop impl = _implementors[i]; + if (impl == NULL) break; // no more in the list + if (!is_alive->do_object_b(impl)) { + // remove this guy from the list by overwriting him with the tail + int lasti = --_nof_implementors; + assert(lasti >= i && lasti < implementors_limit, "just checking"); + _implementors[i] = _implementors[lasti]; + _implementors[lasti] = NULL; + --i; // rerun the loop at this index + } + } + } else { + for (int i = 0; i < implementors_limit; i++) { + keep_alive->do_oop(&adr_implementors()[i]); + } + } + Klass::follow_weak_klass_links(is_alive, keep_alive); +} + + +void instanceKlass::remove_unshareable_info() { + Klass::remove_unshareable_info(); + init_implementor(); +} + + +static void clear_all_breakpoints(methodOop m) { + m->clear_all_breakpoints(); +} + + +void instanceKlass::release_C_heap_structures() { + // Deallocate oop map cache + if (_oop_map_cache != NULL) { + delete _oop_map_cache; + _oop_map_cache = NULL; + } + + // Deallocate JNI identifiers for jfieldIDs + JNIid::deallocate(jni_ids()); + set_jni_ids(NULL); + + jmethodID* jmeths = methods_jmethod_ids_acquire(); + if (jmeths != (jmethodID*)NULL) { + release_set_methods_jmethod_ids(NULL); + FreeHeap(jmeths); + } + + int* indices = methods_cached_itable_indices_acquire(); + if (indices != (int*)NULL) { + release_set_methods_cached_itable_indices(NULL); + FreeHeap(indices); + } + + // release dependencies + nmethodBucket* b = _dependencies; + _dependencies = NULL; + while (b != NULL) { + nmethodBucket* next = b->next(); + delete b; + b = next; + } + + // Deallocate breakpoint records + if (breakpoints() != 0x0) { + methods_do(clear_all_breakpoints); + assert(breakpoints() == 0x0, "should have cleared breakpoints"); + } + + // deallocate information about previous versions + if (_previous_versions != NULL) { + for (int i = _previous_versions->length() - 1; i >= 0; i--) { + PreviousVersionNode * pv_node = _previous_versions->at(i); + delete pv_node; + } + delete _previous_versions; + _previous_versions = NULL; + } + + // deallocate the cached class file + if (_cached_class_file_bytes != NULL) { + os::free(_cached_class_file_bytes); + _cached_class_file_bytes = NULL; + _cached_class_file_len = 0; + } +} + +char* instanceKlass::signature_name() const { + const char* src = (const char*) (name()->as_C_string()); + const int src_length = (int)strlen(src); + char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); + int src_index = 0; + int dest_index = 0; + dest[dest_index++] = 'L'; + while (src_index < src_length) { + dest[dest_index++] = src[src_index++]; + } + dest[dest_index++] = ';'; + dest[dest_index] = '\0'; + return dest; +} + +// different verisons of is_same_class_package +bool instanceKlass::is_same_class_package(klassOop class2) { + klassOop class1 = as_klassOop(); + oop classloader1 = instanceKlass::cast(class1)->class_loader(); + symbolOop classname1 = Klass::cast(class1)->name(); + + if (Klass::cast(class2)->oop_is_objArray()) { + class2 = objArrayKlass::cast(class2)->bottom_klass(); + } + oop classloader2; + if (Klass::cast(class2)->oop_is_instance()) { + classloader2 = instanceKlass::cast(class2)->class_loader(); + } else { + assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array"); + classloader2 = NULL; + } + symbolOop classname2 = Klass::cast(class2)->name(); + + return instanceKlass::is_same_class_package(classloader1, classname1, + classloader2, classname2); +} + +bool instanceKlass::is_same_class_package(oop classloader2, symbolOop classname2) { + klassOop class1 = as_klassOop(); + oop classloader1 = instanceKlass::cast(class1)->class_loader(); + symbolOop classname1 = Klass::cast(class1)->name(); + + return instanceKlass::is_same_class_package(classloader1, classname1, + classloader2, classname2); +} + +// return true if two classes are in the same package, classloader +// and classname information is enough to determine a class's package +bool instanceKlass::is_same_class_package(oop class_loader1, symbolOop class_name1, + oop class_loader2, symbolOop class_name2) { + if (class_loader1 != class_loader2) { + return false; + } else { + ResourceMark rm; + + // The symbolOop's are in UTF8 encoding. Since we only need to check explicitly + // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. + // Otherwise, we just compare jbyte values between the strings. + jbyte *name1 = class_name1->base(); + jbyte *name2 = class_name2->base(); + + jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); + jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); + + if ((last_slash1 == NULL) || (last_slash2 == NULL)) { + // One of the two doesn't have a package. Only return true + // if the other one also doesn't have a package. + return last_slash1 == last_slash2; + } else { + // Skip over '['s + if (*name1 == '[') { + do { + name1++; + } while (*name1 == '['); + if (*name1 != 'L') { + // Something is terribly wrong. Shouldn't be here. + return false; + } + } + if (*name2 == '[') { + do { + name2++; + } while (*name2 == '['); + if (*name2 != 'L') { + // Something is terribly wrong. Shouldn't be here. + return false; + } + } + + // Check that package part is identical + int length1 = last_slash1 - name1; + int length2 = last_slash2 - name2; + + return UTF8::equal(name1, length1, name2, length2); + } + } +} + + +jint instanceKlass::compute_modifier_flags(TRAPS) const { + klassOop k = as_klassOop(); + jint access = access_flags().as_int(); + + // But check if it happens to be member class. + typeArrayOop inner_class_list = inner_classes(); + int length = (inner_class_list == NULL) ? 0 : inner_class_list->length(); + assert (length % instanceKlass::inner_class_next_offset == 0, "just checking"); + if (length > 0) { + typeArrayHandle inner_class_list_h(THREAD, inner_class_list); + instanceKlassHandle ik(THREAD, k); + for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) { + int ioff = inner_class_list_h->ushort_at( + i + instanceKlass::inner_class_inner_class_info_offset); + + // Inner class attribute can be zero, skip it. + // Strange but true: JVM spec. allows null inner class refs. + if (ioff == 0) continue; + + // only look at classes that are already loaded + // since we are looking for the flags for our self. + symbolOop inner_name = ik->constants()->klass_name_at(ioff); + if ((ik->name() == inner_name)) { + // This is really a member class. + access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset); + break; + } + } + } + // Remember to strip ACC_SUPER bit + return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; +} + +jint instanceKlass::jvmti_class_status() const { + jint result = 0; + + if (is_linked()) { + result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; + } + + if (is_initialized()) { + assert(is_linked(), "Class status is not consistent"); + result |= JVMTI_CLASS_STATUS_INITIALIZED; + } + if (is_in_error_state()) { + result |= JVMTI_CLASS_STATUS_ERROR; + } + return result; +} + +methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) { + itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); + int method_table_offset_in_words = ioe->offset()/wordSize; + int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) + / itableOffsetEntry::size(); + + for (int cnt = 0 ; ; cnt ++, ioe ++) { + // If the interface isn't implemented by the reciever class, + // the VM should throw IncompatibleClassChangeError. + if (cnt >= nof_interfaces) { + THROW_OOP_0(vmSymbols::java_lang_IncompatibleClassChangeError()); + } + + klassOop ik = ioe->interface_klass(); + if (ik == holder) break; + } + + itableMethodEntry* ime = ioe->first_method_entry(as_klassOop()); + methodOop m = ime[index].method(); + if (m == NULL) { + THROW_OOP_0(vmSymbols::java_lang_AbstractMethodError()); + } + return m; +} + +// On-stack replacement stuff +void instanceKlass::add_osr_nmethod(nmethod* n) { + // only one compilation can be active + NEEDS_CLEANUP + // This is a short non-blocking critical region, so the no safepoint check is ok. + OsrList_lock->lock_without_safepoint_check(); + assert(n->is_osr_method(), "wrong kind of nmethod"); + n->set_link(osr_nmethods_head()); + set_osr_nmethods_head(n); + // Remember to unlock again + OsrList_lock->unlock(); +} + + +void instanceKlass::remove_osr_nmethod(nmethod* n) { + // This is a short non-blocking critical region, so the no safepoint check is ok. + OsrList_lock->lock_without_safepoint_check(); + assert(n->is_osr_method(), "wrong kind of nmethod"); + nmethod* last = NULL; + nmethod* cur = osr_nmethods_head(); + // Search for match + while(cur != NULL && cur != n) { + last = cur; + cur = cur->link(); + } + if (cur == n) { + if (last == NULL) { + // Remove first element + set_osr_nmethods_head(osr_nmethods_head()->link()); + } else { + last->set_link(cur->link()); + } + } + n->set_link(NULL); + // Remember to unlock again + OsrList_lock->unlock(); +} + +nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci) const { + // This is a short non-blocking critical region, so the no safepoint check is ok. + OsrList_lock->lock_without_safepoint_check(); + nmethod* osr = osr_nmethods_head(); + while (osr != NULL) { + assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); + if (osr->method() == m && + (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { + // Found a match - return it. + OsrList_lock->unlock(); + return osr; + } + osr = osr->link(); + } + OsrList_lock->unlock(); + return NULL; +} + +// ----------------------------------------------------------------------------------------------------- +#ifndef PRODUCT + +// Printing + +void FieldPrinter::do_field(fieldDescriptor* fd) { + if (fd->is_static() == (_obj == NULL)) { + _st->print(" - "); + fd->print_on(_st); + _st->cr(); + } else { + fd->print_on_for(_st, _obj); + _st->cr(); + } +} + + +void instanceKlass::oop_print_on(oop obj, outputStream* st) { + Klass::oop_print_on(obj, st); + + if (as_klassOop() == SystemDictionary::string_klass()) { + typeArrayOop value = java_lang_String::value(obj); + juint offset = java_lang_String::offset(obj); + juint length = java_lang_String::length(obj); + if (value != NULL && + value->is_typeArray() && + offset <= (juint) value->length() && + offset + length <= (juint) value->length()) { + st->print("string: "); + Handle h_obj(obj); + java_lang_String::print(h_obj, st); + st->cr(); + if (!WizardMode) return; // that is enough + } + } + + st->print_cr("fields:"); + FieldPrinter print_nonstatic_field(st, obj); + do_nonstatic_fields(&print_nonstatic_field); + + if (as_klassOop() == SystemDictionary::class_klass()) { + klassOop mirrored_klass = java_lang_Class::as_klassOop(obj); + st->print(" - fake entry for mirror: "); + mirrored_klass->print_value_on(st); + st->cr(); + st->print(" - fake entry resolved_constructor: "); + methodOop ctor = java_lang_Class::resolved_constructor(obj); + ctor->print_value_on(st); + klassOop array_klass = java_lang_Class::array_klass(obj); + st->print(" - fake entry for array: "); + array_klass->print_value_on(st); + st->cr(); + st->cr(); + } +} + +void instanceKlass::oop_print_value_on(oop obj, outputStream* st) { + st->print("a "); + name()->print_value_on(st); + obj->print_address_on(st); +} + +#endif + +const char* instanceKlass::internal_name() const { + return external_name(); +} + + + +// Verification + +class VerifyFieldClosure: public OopClosure { + public: + void do_oop(oop* p) { + guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap"); + if (!(*p)->is_oop_or_null()) { + tty->print_cr("Failed: %p -> %p",p,(address)*p); + Universe::print(); + guarantee(false, "boom"); + } + } +}; + + +void instanceKlass::oop_verify_on(oop obj, outputStream* st) { + Klass::oop_verify_on(obj, st); + VerifyFieldClosure blk; + oop_oop_iterate(obj, &blk); +} + +#ifndef PRODUCT + +void instanceKlass::verify_class_klass_nonstatic_oop_maps(klassOop k) { + // This verification code is disabled. JDK_Version::is_gte_jdk14x_version() + // cannot be called since this function is called before the VM is + // able to determine what JDK version is running with. + // The check below always is false since 1.4. + return; + + // This verification code temporarily disabled for the 1.4 + // reflection implementation since java.lang.Class now has + // Java-level instance fields. Should rewrite this to handle this + // case. + if (!(JDK_Version::is_gte_jdk14x_version() && UseNewReflection)) { + // Verify that java.lang.Class instances have a fake oop field added. + instanceKlass* ik = instanceKlass::cast(k); + + // Check that we have the right class + static bool first_time = true; + guarantee(k == SystemDictionary::class_klass() && first_time, "Invalid verify of maps"); + first_time = false; + const int extra = java_lang_Class::number_of_fake_oop_fields; + guarantee(ik->nonstatic_field_size() == extra, "just checking"); + guarantee(ik->nonstatic_oop_map_size() == 1, "just checking"); + guarantee(ik->size_helper() == align_object_size(instanceOopDesc::header_size() + extra), "just checking"); + + // Check that the map is (2,extra) + int offset = java_lang_Class::klass_offset; + + OopMapBlock* map = ik->start_of_nonstatic_oop_maps(); + guarantee(map->offset() == offset && map->length() == extra, "just checking"); + } +} + +#endif + + +/* JNIid class for jfieldIDs only */ + JNIid::JNIid(klassOop holder, int offset, JNIid* next) { + _holder = holder; + _offset = offset; + _next = next; + debug_only(_is_static_field_id = false;) + } + + + JNIid* JNIid::find(int offset) { + JNIid* current = this; + while (current != NULL) { + if (current->offset() == offset) return current; + current = current->next(); + } + return NULL; + } + +void JNIid::oops_do(OopClosure* f) { + for (JNIid* cur = this; cur != NULL; cur = cur->next()) { + f->do_oop(cur->holder_addr()); + } +} + +void JNIid::deallocate(JNIid* current) { + while (current != NULL) { + JNIid* next = current->next(); + delete current; + current = next; + } + } + + + void JNIid::verify(klassOop holder) { + int first_field_offset = instanceKlass::cast(holder)->offset_of_static_fields(); + int end_field_offset; + end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize); + + JNIid* current = this; + while (current != NULL) { + guarantee(current->holder() == holder, "Invalid klass in JNIid"); + #ifdef ASSERT + int o = current->offset(); + if (current->is_static_field_id()) { + guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); + } + #endif + current = current->next(); + } + } + + +#ifdef ASSERT + void instanceKlass::set_init_state(ClassState state) { + bool good_state = as_klassOop()->is_shared() ? (_init_state <= state) + : (_init_state < state); + assert(good_state || state == allocated, "illegal state transition"); + _init_state = state; + } +#endif + + +// RedefineClasses() support for previous versions: + +// Add an information node that contains weak references to the +// interesting parts of the previous version of the_class. +void instanceKlass::add_previous_version(instanceKlassHandle ikh, + BitMap * emcp_methods, int emcp_method_count) { + assert(Thread::current()->is_VM_thread(), + "only VMThread can add previous versions"); + + if (_previous_versions == NULL) { + // This is the first previous version so make some space. + // Start with 2 elements under the assumption that the class + // won't be redefined much. + _previous_versions = new (ResourceObj::C_HEAP) + GrowableArray<PreviousVersionNode *>(2, true); + } + + // RC_TRACE macro has an embedded ResourceMark + RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d", + ikh->external_name(), _previous_versions->length(), emcp_method_count)); + constantPoolHandle cp_h(ikh->constants()); + jweak cp_ref = JNIHandles::make_weak_global(cp_h); + PreviousVersionNode * pv_node = NULL; + objArrayOop old_methods = ikh->methods(); + + if (emcp_method_count == 0) { + pv_node = new PreviousVersionNode(cp_ref, NULL); + RC_TRACE(0x00000400, + ("add: all methods are obsolete; flushing any EMCP weak refs")); + } else { + int local_count = 0; + GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP) + GrowableArray<jweak>(emcp_method_count, true); + for (int i = 0; i < old_methods->length(); i++) { + if (emcp_methods->at(i)) { + // this old method is EMCP so save a weak ref + methodOop old_method = (methodOop) old_methods->obj_at(i); + methodHandle old_method_h(old_method); + jweak method_ref = JNIHandles::make_weak_global(old_method_h); + method_refs->append(method_ref); + if (++local_count >= emcp_method_count) { + // no more EMCP methods so bail out now + break; + } + } + } + pv_node = new PreviousVersionNode(cp_ref, method_refs); + } + + _previous_versions->append(pv_node); + + // Using weak references allows the interesting parts of previous + // classes to be GC'ed when they are no longer needed. Since the + // caller is the VMThread and we are at a safepoint, this is a good + // time to clear out unused weak references. + + RC_TRACE(0x00000400, ("add: previous version length=%d", + _previous_versions->length())); + + // skip the last entry since we just added it + for (int i = _previous_versions->length() - 2; i >= 0; i--) { + // check the previous versions array for a GC'ed weak refs + pv_node = _previous_versions->at(i); + cp_ref = pv_node->prev_constant_pool(); + assert(cp_ref != NULL, "weak cp ref was unexpectedly cleared"); + if (cp_ref == NULL) { + delete pv_node; + _previous_versions->remove_at(i); + // Since we are traversing the array backwards, we don't have to + // do anything special with the index. + continue; // robustness + } + + constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); + if (cp == NULL) { + // this entry has been GC'ed so remove it + delete pv_node; + _previous_versions->remove_at(i); + // Since we are traversing the array backwards, we don't have to + // do anything special with the index. + continue; + } else { + RC_TRACE(0x00000400, ("add: previous version @%d is alive", i)); + } + + GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods(); + if (method_refs != NULL) { + RC_TRACE(0x00000400, ("add: previous methods length=%d", + method_refs->length())); + for (int j = method_refs->length() - 1; j >= 0; j--) { + jweak method_ref = method_refs->at(j); + assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); + if (method_ref == NULL) { + method_refs->remove_at(j); + // Since we are traversing the array backwards, we don't have to + // do anything special with the index. + continue; // robustness + } + + methodOop method = (methodOop)JNIHandles::resolve(method_ref); + if (method == NULL || emcp_method_count == 0) { + // This method entry has been GC'ed or the current + // RedefineClasses() call has made all methods obsolete + // so remove it. + JNIHandles::destroy_weak_global(method_ref); + method_refs->remove_at(j); + } else { + // RC_TRACE macro has an embedded ResourceMark + RC_TRACE(0x00000400, + ("add: %s(%s): previous method @%d in version @%d is alive", + method->name()->as_C_string(), method->signature()->as_C_string(), + j, i)); + } + } + } + } + + int obsolete_method_count = old_methods->length() - emcp_method_count; + + if (emcp_method_count != 0 && obsolete_method_count != 0 && + _previous_versions->length() > 1) { + // We have a mix of obsolete and EMCP methods. If there is more + // than the previous version that we just added, then we have to + // clear out any matching EMCP method entries the hard way. + int local_count = 0; + for (int i = 0; i < old_methods->length(); i++) { + if (!emcp_methods->at(i)) { + // only obsolete methods are interesting + methodOop old_method = (methodOop) old_methods->obj_at(i); + symbolOop m_name = old_method->name(); + symbolOop m_signature = old_method->signature(); + + // skip the last entry since we just added it + for (int j = _previous_versions->length() - 2; j >= 0; j--) { + // check the previous versions array for a GC'ed weak refs + pv_node = _previous_versions->at(j); + cp_ref = pv_node->prev_constant_pool(); + assert(cp_ref != NULL, "weak cp ref was unexpectedly cleared"); + if (cp_ref == NULL) { + delete pv_node; + _previous_versions->remove_at(j); + // Since we are traversing the array backwards, we don't have to + // do anything special with the index. + continue; // robustness + } + + constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); + if (cp == NULL) { + // this entry has been GC'ed so remove it + delete pv_node; + _previous_versions->remove_at(j); + // Since we are traversing the array backwards, we don't have to + // do anything special with the index. + continue; + } + + GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods(); + if (method_refs == NULL) { + // We have run into a PreviousVersion generation where + // all methods were made obsolete during that generation's + // RedefineClasses() operation. At the time of that + // operation, all EMCP methods were flushed so we don't + // have to go back any further. + // + // A NULL method_refs is different than an empty method_refs. + // We cannot infer any optimizations about older generations + // from an empty method_refs for the current generation. + break; + } + + for (int k = method_refs->length() - 1; k >= 0; k--) { + jweak method_ref = method_refs->at(k); + assert(method_ref != NULL, + "weak method ref was unexpectedly cleared"); + if (method_ref == NULL) { + method_refs->remove_at(k); + // Since we are traversing the array backwards, we don't + // have to do anything special with the index. + continue; // robustness + } + + methodOop method = (methodOop)JNIHandles::resolve(method_ref); + if (method == NULL) { + // this method entry has been GC'ed so skip it + JNIHandles::destroy_weak_global(method_ref); + method_refs->remove_at(k); + continue; + } + + if (method->name() == m_name && + method->signature() == m_signature) { + // The current RedefineClasses() call has made all EMCP + // versions of this method obsolete so mark it as obsolete + // and remove the weak ref. + RC_TRACE(0x00000400, + ("add: %s(%s): flush obsolete method @%d in version @%d", + m_name->as_C_string(), m_signature->as_C_string(), k, j)); + + method->set_is_obsolete(); + JNIHandles::destroy_weak_global(method_ref); + method_refs->remove_at(k); + break; + } + } + + // The previous loop may not find a matching EMCP method, but + // that doesn't mean that we can optimize and not go any + // further back in the PreviousVersion generations. The EMCP + // method for this generation could have already been GC'ed, + // but there still may be an older EMCP method that has not + // been GC'ed. + } + + if (++local_count >= obsolete_method_count) { + // no more obsolete methods so bail out now + break; + } + } + } + } +} // end add_previous_version() + + +// Determine if instanceKlass has a previous version. +bool instanceKlass::has_previous_version() const { + if (_previous_versions == NULL) { + // no previous versions array so answer is easy + return false; + } + + for (int i = _previous_versions->length() - 1; i >= 0; i--) { + // Check the previous versions array for an info node that hasn't + // been GC'ed + PreviousVersionNode * pv_node = _previous_versions->at(i); + + jweak cp_ref = pv_node->prev_constant_pool(); + assert(cp_ref != NULL, "weak reference was unexpectedly cleared"); + if (cp_ref == NULL) { + continue; // robustness + } + + constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); + if (cp != NULL) { + // we have at least one previous version + return true; + } + + // We don't have to check the method refs. If the constant pool has + // been GC'ed then so have the methods. + } + + // all of the underlying nodes' info has been GC'ed + return false; +} // end has_previous_version() + +methodOop instanceKlass::method_with_idnum(int idnum) { + methodOop m = NULL; + if (idnum < methods()->length()) { + m = (methodOop) methods()->obj_at(idnum); + } + if (m == NULL || m->method_idnum() != idnum) { + for (int index = 0; index < methods()->length(); ++index) { + m = (methodOop) methods()->obj_at(index); + if (m->method_idnum() == idnum) { + return m; + } + } + } + return m; +} + + +// Set the annotation at 'idnum' to 'anno'. +// We don't want to create or extend the array if 'anno' is NULL, since that is the +// default value. However, if the array exists and is long enough, we must set NULL values. +void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) { + objArrayOop md = *md_p; + if (md != NULL && md->length() > idnum) { + md->obj_at_put(idnum, anno); + } else if (anno != NULL) { + // create the array + int length = MAX2(idnum+1, (int)_idnum_allocated_count); + md = oopFactory::new_system_objArray(length, Thread::current()); + if (*md_p != NULL) { + // copy the existing entries + for (int index = 0; index < (*md_p)->length(); index++) { + md->obj_at_put(index, (*md_p)->obj_at(index)); + } + } + set_annotations(md, md_p); + md->obj_at_put(idnum, anno); + } // if no array and idnum isn't included there is nothing to do +} + +// Construct a PreviousVersionNode entry for the array hung off +// the instanceKlass. +PreviousVersionNode::PreviousVersionNode(jweak prev_constant_pool, + GrowableArray<jweak>* prev_EMCP_methods) { + + _prev_constant_pool = prev_constant_pool; + _prev_EMCP_methods = prev_EMCP_methods; +} + + +// Destroy a PreviousVersionNode +PreviousVersionNode::~PreviousVersionNode() { + if (_prev_constant_pool != NULL) { + JNIHandles::destroy_weak_global(_prev_constant_pool); + } + + if (_prev_EMCP_methods != NULL) { + for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) { + jweak method_ref = _prev_EMCP_methods->at(i); + if (method_ref != NULL) { + JNIHandles::destroy_weak_global(method_ref); + } + } + delete _prev_EMCP_methods; + } +} + + +// Construct a PreviousVersionInfo entry +PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) { + _prev_constant_pool_handle = constantPoolHandle(); // NULL handle + _prev_EMCP_method_handles = NULL; + + jweak cp_ref = pv_node->prev_constant_pool(); + assert(cp_ref != NULL, "weak constant pool ref was unexpectedly cleared"); + if (cp_ref == NULL) { + return; // robustness + } + + constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); + if (cp == NULL) { + // Weak reference has been GC'ed. Since the constant pool has been + // GC'ed, the methods have also been GC'ed. + return; + } + + // make the constantPoolOop safe to return + _prev_constant_pool_handle = constantPoolHandle(cp); + + GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods(); + if (method_refs == NULL) { + // the instanceKlass did not have any EMCP methods + return; + } + + _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10); + + int n_methods = method_refs->length(); + for (int i = 0; i < n_methods; i++) { + jweak method_ref = method_refs->at(i); + assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); + if (method_ref == NULL) { + continue; // robustness + } + + methodOop method = (methodOop)JNIHandles::resolve(method_ref); + if (method == NULL) { + // this entry has been GC'ed so skip it + continue; + } + + // make the methodOop safe to return + _prev_EMCP_method_handles->append(methodHandle(method)); + } +} + + +// Destroy a PreviousVersionInfo +PreviousVersionInfo::~PreviousVersionInfo() { + // Since _prev_EMCP_method_handles is not C-heap allocated, we + // don't have to delete it. +} + + +// Construct a helper for walking the previous versions array +PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) { + _previous_versions = ik->previous_versions(); + _current_index = 0; + // _hm needs no initialization + _current_p = NULL; +} + + +// Destroy a PreviousVersionWalker +PreviousVersionWalker::~PreviousVersionWalker() { + // Delete the current info just in case the caller didn't walk to + // the end of the previous versions list. No harm if _current_p is + // already NULL. + delete _current_p; + + // When _hm is destroyed, all the Handles returned in + // PreviousVersionInfo objects will be destroyed. + // Also, after this destructor is finished it will be + // safe to delete the GrowableArray allocated in the + // PreviousVersionInfo objects. +} + + +// Return the interesting information for the next previous version +// of the klass. Returns NULL if there are no more previous versions. +PreviousVersionInfo* PreviousVersionWalker::next_previous_version() { + if (_previous_versions == NULL) { + // no previous versions so nothing to return + return NULL; + } + + delete _current_p; // cleanup the previous info for the caller + _current_p = NULL; // reset to NULL so we don't delete same object twice + + int length = _previous_versions->length(); + + while (_current_index < length) { + PreviousVersionNode * pv_node = _previous_versions->at(_current_index++); + PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP) + PreviousVersionInfo(pv_node); + + constantPoolHandle cp_h = pv_info->prev_constant_pool_handle(); + if (cp_h.is_null()) { + delete pv_info; + + // The underlying node's info has been GC'ed so try the next one. + // We don't have to check the methods. If the constant pool has + // GC'ed then so have the methods. + continue; + } + + // Found a node with non GC'ed info so return it. The caller will + // need to delete pv_info when they are done with it. + _current_p = pv_info; + return pv_info; + } + + // all of the underlying nodes' info has been GC'ed + return NULL; +} // end next_previous_version()