JDK14/Java14源码在线阅读
/*
* Copyright (c) 2014, 2019, 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/classFileStream.hpp"
#include "classfile/classListParser.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/classLoaderData.inline.hpp"
#include "classfile/classLoaderDataGraph.hpp"
#include "classfile/classLoaderExt.hpp"
#include "classfile/dictionary.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/verificationType.hpp"
#include "classfile/vmSymbols.hpp"
#include "logging/log.hpp"
#include "memory/allocation.hpp"
#include "memory/archiveUtils.hpp"
#include "memory/filemap.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "memory/dynamicArchive.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/klass.inline.hpp"
#include "oops/objArrayOop.inline.hpp"
#include "oops/oop.inline.hpp"
#include "oops/typeArrayOop.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/mutexLocker.hpp"
#include "utilities/hashtable.inline.hpp"
#include "utilities/resourceHash.hpp"
#include "utilities/stringUtils.hpp"
objArrayOop SystemDictionaryShared::_shared_protection_domains = NULL;
objArrayOop SystemDictionaryShared::_shared_jar_urls = NULL;
objArrayOop SystemDictionaryShared::_shared_jar_manifests = NULL;
DEBUG_ONLY(bool SystemDictionaryShared::_no_class_loading_should_happen = false;)
class DumpTimeSharedClassInfo: public CHeapObj<mtClass> {
bool _excluded;
public:
struct DTConstraint {
Symbol* _name;
Symbol* _from_name;
DTConstraint() : _name(NULL), _from_name(NULL) {}
DTConstraint(Symbol* n, Symbol* fn) : _name(n), _from_name(fn) {}
};
InstanceKlass* _klass;
int _id;
int _clsfile_size;
int _clsfile_crc32;
GrowableArray<DTConstraint>* _verifier_constraints;
GrowableArray<char>* _verifier_constraint_flags;
DumpTimeSharedClassInfo() {
_klass = NULL;
_id = -1;
_clsfile_size = -1;
_clsfile_crc32 = -1;
_excluded = false;
_verifier_constraints = NULL;
_verifier_constraint_flags = NULL;
}
void add_verification_constraint(InstanceKlass* k, Symbol* name,
Symbol* from_name, bool from_field_is_protected, bool from_is_array, bool from_is_object);
bool is_builtin() {
return SystemDictionaryShared::is_builtin(_klass);
}
int num_constraints() {
if (_verifier_constraint_flags != NULL) {
return _verifier_constraint_flags->length();
} else {
return 0;
}
}
void metaspace_pointers_do(MetaspaceClosure* it) {
it->push(&_klass);
if (_verifier_constraints != NULL) {
for (int i = 0; i < _verifier_constraints->length(); i++) {
DTConstraint* cons = _verifier_constraints->adr_at(i);
it->push(&cons->_name);
it->push(&cons->_from_name);
}
}
}
void set_excluded() {
_excluded = true;
}
bool is_excluded() {
// _klass may become NULL due to DynamicArchiveBuilder::set_to_null
return _excluded || _klass == NULL;
}
};
class DumpTimeSharedClassTable: public ResourceHashtable<
InstanceKlass*,
DumpTimeSharedClassInfo,
primitive_hash<InstanceKlass*>,
primitive_equals<InstanceKlass*>,
15889, // prime number
ResourceObj::C_HEAP>
{
int _builtin_count;
int _unregistered_count;
public:
DumpTimeSharedClassInfo* find_or_allocate_info_for(InstanceKlass* k) {
DumpTimeSharedClassInfo* p = get(k);
if (p == NULL) {
assert(!SystemDictionaryShared::no_class_loading_should_happen(),
"no new classes can be loaded while dumping archive");
put(k, DumpTimeSharedClassInfo());
p = get(k);
assert(p != NULL, "sanity");
p->_klass = k;
}
return p;
}
class CountClassByCategory : StackObj {
DumpTimeSharedClassTable* _table;
public:
CountClassByCategory(DumpTimeSharedClassTable* table) : _table(table) {}
bool do_entry(InstanceKlass* k, DumpTimeSharedClassInfo& info) {
if (!info.is_excluded()) {
if (info.is_builtin()) {
++ _table->_builtin_count;
} else {
++ _table->_unregistered_count;
}
}
return true; // keep on iterating
}
};
void update_counts() {
_builtin_count = 0;
_unregistered_count = 0;
CountClassByCategory counter(this);
iterate(&counter);
}
int count_of(bool is_builtin) const {
if (is_builtin) {
return _builtin_count;
} else {
return _unregistered_count;
}
}
};
class RunTimeSharedClassInfo {
public:
struct CrcInfo {
int _clsfile_size;
int _clsfile_crc32;
};
// This is different than DumpTimeSharedClassInfo::DTConstraint. We use
// u4 instead of Symbol* to save space on 64-bit CPU.
struct RTConstraint {
u4 _name;
u4 _from_name;
};
InstanceKlass* _klass;
int _num_constraints;
// optional CrcInfo _crc; (only for UNREGISTERED classes)
// optional RTConstraint _verifier_constraints[_num_constraints]
// optional char _verifier_constraint_flags[_num_constraints]
private:
static size_t header_size_size() {
return sizeof(RunTimeSharedClassInfo);
}
static size_t crc_size(InstanceKlass* klass) {
if (!SystemDictionaryShared::is_builtin(klass)) {
return sizeof(CrcInfo);
} else {
return 0;
}
}
static size_t verifier_constraints_size(int num_constraints) {
return sizeof(RTConstraint) * num_constraints;
}
static size_t verifier_constraint_flags_size(int num_constraints) {
return sizeof(char) * num_constraints;
}
public:
static size_t byte_size(InstanceKlass* klass, int num_constraints) {
return header_size_size() +
crc_size(klass) +
verifier_constraints_size(num_constraints) +
verifier_constraint_flags_size(num_constraints);
}
private:
size_t crc_offset() const {
return header_size_size();
}
size_t verifier_constraints_offset() const {
return crc_offset() + crc_size(_klass);
}
size_t verifier_constraint_flags_offset() const {
return verifier_constraints_offset() + verifier_constraints_size(_num_constraints);
}
void check_constraint_offset(int i) const {
assert(0 <= i && i < _num_constraints, "sanity");
}
public:
CrcInfo* crc() const {
assert(crc_size(_klass) > 0, "must be");
return (CrcInfo*)(address(this) + crc_offset());
}
RTConstraint* verifier_constraints() {
assert(_num_constraints > 0, "sanity");
return (RTConstraint*)(address(this) + verifier_constraints_offset());
}
RTConstraint* verifier_constraint_at(int i) {
check_constraint_offset(i);
return verifier_constraints() + i;
}
char* verifier_constraint_flags() {
assert(_num_constraints > 0, "sanity");
return (char*)(address(this) + verifier_constraint_flags_offset());
}
static u4 object_delta_u4(Symbol* sym) {
if (DynamicDumpSharedSpaces) {
sym = DynamicArchive::original_to_target(sym);
}
return MetaspaceShared::object_delta_u4(sym);
}
void init(DumpTimeSharedClassInfo& info) {
_klass = info._klass;
if (!SystemDictionaryShared::is_builtin(_klass)) {
CrcInfo* c = crc();
c->_clsfile_size = info._clsfile_size;
c->_clsfile_crc32 = info._clsfile_crc32;
}
_num_constraints = info.num_constraints();
if (_num_constraints > 0) {
RTConstraint* constraints = verifier_constraints();
char* flags = verifier_constraint_flags();
int i;
for (i = 0; i < _num_constraints; i++) {
constraints[i]._name = object_delta_u4(info._verifier_constraints->at(i)._name);
constraints[i]._from_name = object_delta_u4(info._verifier_constraints->at(i)._from_name);
}
for (i = 0; i < _num_constraints; i++) {
flags[i] = info._verifier_constraint_flags->at(i);
}
}
if (DynamicDumpSharedSpaces) {
_klass = DynamicArchive::original_to_target(info._klass);
}
ArchivePtrMarker::mark_pointer(&_klass);
}
bool matches(int clsfile_size, int clsfile_crc32) const {
return crc()->_clsfile_size == clsfile_size &&
crc()->_clsfile_crc32 == clsfile_crc32;
}
Symbol* get_constraint_name(int i) {
return (Symbol*)(SharedBaseAddress + verifier_constraint_at(i)->_name);
}
Symbol* get_constraint_from_name(int i) {
return (Symbol*)(SharedBaseAddress + verifier_constraint_at(i)->_from_name);
}
char get_constraint_flag(int i) {
check_constraint_offset(i);
return verifier_constraint_flags()[i];
}
private:
// ArchiveCompactor::allocate() has reserved a pointer immediately before
// archived InstanceKlasses. We can use this slot to do a quick
// lookup of InstanceKlass* -> RunTimeSharedClassInfo* without
// building a new hashtable.
//
// info_pointer_addr(klass) --> 0x0100 RunTimeSharedClassInfo*
// InstanceKlass* klass --> 0x0108 <C++ vtbl>
// 0x0110 fields from Klass ...
static RunTimeSharedClassInfo** info_pointer_addr(InstanceKlass* klass) {
return &((RunTimeSharedClassInfo**)klass)[-1];
}
public:
static RunTimeSharedClassInfo* get_for(InstanceKlass* klass) {
return *info_pointer_addr(klass);
}
static void set_for(InstanceKlass* klass, RunTimeSharedClassInfo* record) {
if (DynamicDumpSharedSpaces) {
klass = DynamicArchive::original_to_buffer(klass);
*info_pointer_addr(klass) = DynamicArchive::buffer_to_target(record);
} else {
*info_pointer_addr(klass) = record;
}
ArchivePtrMarker::mark_pointer(info_pointer_addr(klass));
}
// Used by RunTimeSharedDictionary to implement OffsetCompactHashtable::EQUALS
static inline bool EQUALS(
const RunTimeSharedClassInfo* value, Symbol* key, int len_unused) {
return (value->_klass->name() == key);
}
};
class RunTimeSharedDictionary : public OffsetCompactHashtable<
Symbol*,
const RunTimeSharedClassInfo*,
RunTimeSharedClassInfo::EQUALS> {};
static DumpTimeSharedClassTable* _dumptime_table = NULL;
// SystemDictionaries in the base layer static archive
static RunTimeSharedDictionary _builtin_dictionary;
static RunTimeSharedDictionary _unregistered_dictionary;
// SystemDictionaries in the top layer dynamic archive
static RunTimeSharedDictionary _dynamic_builtin_dictionary;
static RunTimeSharedDictionary _dynamic_unregistered_dictionary;
oop SystemDictionaryShared::shared_protection_domain(int index) {
return _shared_protection_domains->obj_at(index);
}
oop SystemDictionaryShared::shared_jar_url(int index) {
return _shared_jar_urls->obj_at(index);
}
oop SystemDictionaryShared::shared_jar_manifest(int index) {
return _shared_jar_manifests->obj_at(index);
}
Handle SystemDictionaryShared::get_shared_jar_manifest(int shared_path_index, TRAPS) {
Handle manifest ;
if (shared_jar_manifest(shared_path_index) == NULL) {
SharedClassPathEntry* ent = FileMapInfo::shared_path(shared_path_index);
long size = ent->manifest_size();
if (size <= 0) {
return Handle();
}
// ByteArrayInputStream bais = new ByteArrayInputStream(buf);
const char* src = ent->manifest();
assert(src != NULL, "No Manifest data");
typeArrayOop buf = oopFactory::new_byteArray(size, CHECK_NH);
typeArrayHandle bufhandle(THREAD, buf);
ArrayAccess<>::arraycopy_from_native(reinterpret_cast<const jbyte*>(src),
buf, typeArrayOopDesc::element_offset<jbyte>(0), size);
Handle bais = JavaCalls::construct_new_instance(SystemDictionary::ByteArrayInputStream_klass(),
vmSymbols::byte_array_void_signature(),
bufhandle, CHECK_NH);
// manifest = new Manifest(bais)
manifest = JavaCalls::construct_new_instance(SystemDictionary::Jar_Manifest_klass(),
vmSymbols::input_stream_void_signature(),
bais, CHECK_NH);
atomic_set_shared_jar_manifest(shared_path_index, manifest());
}
manifest = Handle(THREAD, shared_jar_manifest(shared_path_index));
assert(manifest.not_null(), "sanity");
return manifest;
}
Handle SystemDictionaryShared::get_shared_jar_url(int shared_path_index, TRAPS) {
Handle url_h;
if (shared_jar_url(shared_path_index) == NULL) {
JavaValue result(T_OBJECT);
const char* path = FileMapInfo::shared_path_name(shared_path_index);
Handle path_string = java_lang_String::create_from_str(path, CHECK_(url_h));
Klass* classLoaders_klass =
SystemDictionary::jdk_internal_loader_ClassLoaders_klass();
JavaCalls::call_static(&result, classLoaders_klass,
vmSymbols::toFileURL_name(),
vmSymbols::toFileURL_signature(),
path_string, CHECK_(url_h));
atomic_set_shared_jar_url(shared_path_index, (oop)result.get_jobject());
}
url_h = Handle(THREAD, shared_jar_url(shared_path_index));
assert(url_h.not_null(), "sanity");
return url_h;
}
Handle SystemDictionaryShared::get_package_name(Symbol* class_name, TRAPS) {
ResourceMark rm(THREAD);
Handle pkgname_string;
char* pkgname = (char*) ClassLoader::package_from_name((const char*) class_name->as_C_string());
if (pkgname != NULL) { // Package prefix found
StringUtils::replace_no_expand(pkgname, "/", ".");
pkgname_string = java_lang_String::create_from_str(pkgname,
CHECK_(pkgname_string));
}
return pkgname_string;
}
// Define Package for shared app classes from JAR file and also checks for
// package sealing (all done in Java code)
// See http://docs.oracle.com/javase/tutorial/deployment/jar/sealman.html
void SystemDictionaryShared::define_shared_package(Symbol* class_name,
Handle class_loader,
Handle manifest,
Handle url,
TRAPS) {
assert(SystemDictionary::is_system_class_loader(class_loader()), "unexpected class loader");
// get_package_name() returns a NULL handle if the class is in unnamed package
Handle pkgname_string = get_package_name(class_name, CHECK);
if (pkgname_string.not_null()) {
Klass* app_classLoader_klass = SystemDictionary::jdk_internal_loader_ClassLoaders_AppClassLoader_klass();
JavaValue result(T_OBJECT);
JavaCallArguments args(3);
args.set_receiver(class_loader);
args.push_oop(pkgname_string);
args.push_oop(manifest);
args.push_oop(url);
JavaCalls::call_virtual(&result, app_classLoader_klass,
vmSymbols::defineOrCheckPackage_name(),
vmSymbols::defineOrCheckPackage_signature(),
&args,
CHECK);
}
}
// Define Package for shared app/platform classes from named module
void SystemDictionaryShared::define_shared_package(Symbol* class_name,
Handle class_loader,
ModuleEntry* mod_entry,
TRAPS) {
assert(mod_entry != NULL, "module_entry should not be NULL");
Handle module_handle(THREAD, mod_entry->module());
Handle pkg_name = get_package_name(class_name, CHECK);
assert(pkg_name.not_null(), "Package should not be null for class in named module");
Klass* classLoader_klass;
if (SystemDictionary::is_system_class_loader(class_loader())) {
classLoader_klass = SystemDictionary::jdk_internal_loader_ClassLoaders_AppClassLoader_klass();
} else {
assert(SystemDictionary::is_platform_class_loader(class_loader()), "unexpected classloader");
classLoader_klass = SystemDictionary::jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass();
}
JavaValue result(T_OBJECT);
JavaCallArguments args(2);
args.set_receiver(class_loader);
args.push_oop(pkg_name);
args.push_oop(module_handle);
JavaCalls::call_virtual(&result, classLoader_klass,
vmSymbols::definePackage_name(),
vmSymbols::definePackage_signature(),
&args,
CHECK);
}
// Get the ProtectionDomain associated with the CodeSource from the classloader.
Handle SystemDictionaryShared::get_protection_domain_from_classloader(Handle class_loader,
Handle url, TRAPS) {
// CodeSource cs = new CodeSource(url, null);
Handle cs = JavaCalls::construct_new_instance(SystemDictionary::CodeSource_klass(),
vmSymbols::url_code_signer_array_void_signature(),
url, Handle(), CHECK_NH);
// protection_domain = SecureClassLoader.getProtectionDomain(cs);
Klass* secureClassLoader_klass = SystemDictionary::SecureClassLoader_klass();
JavaValue obj_result(T_OBJECT);
JavaCalls::call_virtual(&obj_result, class_loader, secureClassLoader_klass,
vmSymbols::getProtectionDomain_name(),
vmSymbols::getProtectionDomain_signature(),
cs, CHECK_NH);
return Handle(THREAD, (oop)obj_result.get_jobject());
}
// Returns the ProtectionDomain associated with the JAR file identified by the url.
Handle SystemDictionaryShared::get_shared_protection_domain(Handle class_loader,
int shared_path_index,
Handle url,
TRAPS) {
Handle protection_domain;
if (shared_protection_domain(shared_path_index) == NULL) {
Handle pd = get_protection_domain_from_classloader(class_loader, url, THREAD);
atomic_set_shared_protection_domain(shared_path_index, pd());
}
// Acquire from the cache because if another thread beats the current one to
// set the shared protection_domain and the atomic_set fails, the current thread
// needs to get the updated protection_domain from the cache.
protection_domain = Handle(THREAD, shared_protection_domain(shared_path_index));
assert(protection_domain.not_null(), "sanity");
return protection_domain;
}
// Returns the ProtectionDomain associated with the moduleEntry.
Handle SystemDictionaryShared::get_shared_protection_domain(Handle class_loader,
ModuleEntry* mod, TRAPS) {
ClassLoaderData *loader_data = mod->loader_data();
if (mod->shared_protection_domain() == NULL) {
Symbol* location = mod->location();
if (location != NULL) {
Handle location_string = java_lang_String::create_from_symbol(
location, CHECK_NH);
Handle url;
JavaValue result(T_OBJECT);
if (location->starts_with("jrt:/")) {
url = JavaCalls::construct_new_instance(SystemDictionary::URL_klass(),
vmSymbols::string_void_signature(),
location_string, CHECK_NH);
} else {
Klass* classLoaders_klass =
SystemDictionary::jdk_internal_loader_ClassLoaders_klass();
JavaCalls::call_static(&result, classLoaders_klass, vmSymbols::toFileURL_name(),
vmSymbols::toFileURL_signature(),
location_string, CHECK_NH);
url = Handle(THREAD, (oop)result.get_jobject());
}
Handle pd = get_protection_domain_from_classloader(class_loader, url,
CHECK_NH);
mod->set_shared_protection_domain(loader_data, pd);
}
}
Handle protection_domain(THREAD, mod->shared_protection_domain());
assert(protection_domain.not_null(), "sanity");
return protection_domain;
}
// Initializes the java.lang.Package and java.security.ProtectionDomain objects associated with
// the given InstanceKlass.
// Returns the ProtectionDomain for the InstanceKlass.
Handle SystemDictionaryShared::init_security_info(Handle class_loader, InstanceKlass* ik, TRAPS) {
Handle pd;
if (ik != NULL) {
int index = ik->shared_classpath_index();
assert(index >= 0, "Sanity");
SharedClassPathEntry* ent = FileMapInfo::shared_path(index);
Symbol* class_name = ik->name();
if (ent->is_modules_image()) {
// For shared app/platform classes originated from the run-time image:
// The ProtectionDomains are cached in the corresponding ModuleEntries
// for fast access by the VM.
ResourceMark rm;
ClassLoaderData *loader_data =
ClassLoaderData::class_loader_data(class_loader());
PackageEntryTable* pkgEntryTable = loader_data->packages();
TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK_(pd));
if (pkg_name != NULL) {
PackageEntry* pkg_entry = pkgEntryTable->lookup_only(pkg_name);
if (pkg_entry != NULL) {
ModuleEntry* mod_entry = pkg_entry->module();
pd = get_shared_protection_domain(class_loader, mod_entry, THREAD);
define_shared_package(class_name, class_loader, mod_entry, CHECK_(pd));
}
}
} else {
// For shared app/platform classes originated from JAR files on the class path:
// Each of the 3 SystemDictionaryShared::_shared_xxx arrays has the same length
// as the shared classpath table in the shared archive (see
// FileMap::_shared_path_table in filemap.hpp for details).
//
// If a shared InstanceKlass k is loaded from the class path, let
//
// index = k->shared_classpath_index():
//
// FileMap::_shared_path_table[index] identifies the JAR file that contains k.
//
// k's protection domain is:
//
// ProtectionDomain pd = _shared_protection_domains[index];
//
// and k's Package is initialized using
//
// manifest = _shared_jar_manifests[index];
// url = _shared_jar_urls[index];
// define_shared_package(class_name, class_loader, manifest, url, CHECK_(pd));
//
// Note that if an element of these 3 _shared_xxx arrays is NULL, it will be initialized by
// the corresponding SystemDictionaryShared::get_shared_xxx() function.
Handle manifest = get_shared_jar_manifest(index, CHECK_(pd));
Handle url = get_shared_jar_url(index, CHECK_(pd));
define_shared_package(class_name, class_loader, manifest, url, CHECK_(pd));
pd = get_shared_protection_domain(class_loader, index, url, CHECK_(pd));
}
}
return pd;
}
bool SystemDictionaryShared::is_sharing_possible(ClassLoaderData* loader_data) {
oop class_loader = loader_data->class_loader();
return (class_loader == NULL ||
SystemDictionary::is_system_class_loader(class_loader) ||
SystemDictionary::is_platform_class_loader(class_loader));
}
// Currently AppCDS only archives classes from the run-time image, the
// -Xbootclasspath/a path, the class path, and the module path.
//
// Check if a shared class can be loaded by the specific classloader. Following
// are the "visible" archived classes for different classloaders.
//
// NULL classloader:
// - see SystemDictionary::is_shared_class_visible()
// Platform classloader:
// - Module class from runtime image. ModuleEntry must be defined in the
// classloader.
// App classloader:
// - Module Class from runtime image and module path. ModuleEntry must be defined in the
// classloader.
// - Class from -cp. The class must have no PackageEntry defined in any of the
// boot/platform/app classloader, or must be in the unnamed module defined in the
// AppClassLoader.
bool SystemDictionaryShared::is_shared_class_visible_for_classloader(
InstanceKlass* ik,
Handle class_loader,
Symbol* pkg_name,
PackageEntry* pkg_entry,
ModuleEntry* mod_entry,
TRAPS) {
assert(class_loader.not_null(), "Class loader should not be NULL");
assert(Universe::is_module_initialized(), "Module system is not initialized");
ResourceMark rm(THREAD);
int path_index = ik->shared_classpath_index();
SharedClassPathEntry* ent =
(SharedClassPathEntry*)FileMapInfo::shared_path(path_index);
if (SystemDictionary::is_platform_class_loader(class_loader())) {
assert(ent != NULL, "shared class for PlatformClassLoader should have valid SharedClassPathEntry");
// The PlatformClassLoader can only load archived class originated from the
// run-time image. The class' PackageEntry/ModuleEntry must be
// defined by the PlatformClassLoader.
if (mod_entry != NULL) {
// PackageEntry/ModuleEntry is found in the classloader. Check if the
// ModuleEntry's location agrees with the archived class' origination.
if (ent->is_modules_image() && mod_entry->location()->starts_with("jrt:")) {
return true; // Module class from the runtime image
}
}
} else if (SystemDictionary::is_system_class_loader(class_loader())) {
assert(ent != NULL, "shared class for system loader should have valid SharedClassPathEntry");
if (pkg_name == NULL) {
// The archived class is in the unnamed package. Currently, the boot image
// does not contain any class in the unnamed package.
assert(!ent->is_modules_image(), "Class in the unnamed package must be from the classpath");
if (path_index >= ClassLoaderExt::app_class_paths_start_index()) {
assert(path_index < ClassLoaderExt::app_module_paths_start_index(), "invalid path_index");
return true;
}
} else {
// Check if this is from a PackageEntry/ModuleEntry defined in the AppClassloader.
if (pkg_entry == NULL) {
// It's not guaranteed that the class is from the classpath if the
// PackageEntry cannot be found from the AppClassloader. Need to check
// the boot and platform classloader as well.
if (get_package_entry(pkg_name, ClassLoaderData::class_loader_data_or_null(SystemDictionary::java_platform_loader())) == NULL &&
get_package_entry(pkg_name, ClassLoaderData::the_null_class_loader_data()) == NULL) {
// The PackageEntry is not defined in any of the boot/platform/app classloaders.
// The archived class must from -cp path and not from the runtime image.
if (!ent->is_modules_image() && path_index >= ClassLoaderExt::app_class_paths_start_index() &&
path_index < ClassLoaderExt::app_module_paths_start_index()) {
return true;
}
}
} else if (mod_entry != NULL) {
// The package/module is defined in the AppClassLoader. We support
// archiving application module class from the runtime image or from
// a named module from a module path.
// Packages from the -cp path are in the unnamed_module.
if (ent->is_modules_image() && mod_entry->location()->starts_with("jrt:")) {
// shared module class from runtime image
return true;
} else if (pkg_entry->in_unnamed_module() && path_index >= ClassLoaderExt::app_class_paths_start_index() &&
path_index < ClassLoaderExt::app_module_paths_start_index()) {
// shared class from -cp
DEBUG_ONLY( \
ClassLoaderData* loader_data = class_loader_data(class_loader); \
assert(mod_entry == loader_data->unnamed_module(), "the unnamed module is not defined in the classloader");)
return true;
} else {
if(!pkg_entry->in_unnamed_module() &&
(path_index >= ClassLoaderExt::app_module_paths_start_index())&&
(path_index < FileMapInfo::get_number_of_shared_paths()) &&
(strcmp(ent->name(), ClassLoader::skip_uri_protocol(mod_entry->location()->as_C_string())) == 0)) {
// shared module class from module path
return true;
} else {
assert(path_index < FileMapInfo::get_number_of_shared_paths(), "invalid path_index");
}
}
}
}
} else {
// TEMP: if a shared class can be found by a custom loader, consider it visible now.
// FIXME: is this actually correct?
return true;
}
return false;
}
bool SystemDictionaryShared::has_platform_or_app_classes() {
if (FileMapInfo::current_info()->has_platform_or_app_classes()) {
return true;
}
if (DynamicArchive::is_mapped() &&
FileMapInfo::dynamic_info()->has_platform_or_app_classes()) {
return true;
}
return false;
}
// The following stack shows how this code is reached:
//
// [0] SystemDictionaryShared::find_or_load_shared_class()
// [1] JVM_FindLoadedClass
// [2] java.lang.ClassLoader.findLoadedClass0()
// [3] java.lang.ClassLoader.findLoadedClass()
// [4] jdk.internal.loader.BuiltinClassLoader.loadClassOrNull()
// [5] jdk.internal.loader.BuiltinClassLoader.loadClass()
// [6] jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(), or
// jdk.internal.loader.ClassLoaders$PlatformClassLoader.loadClass()
//
// AppCDS supports fast class loading for these 2 built-in class loaders:
// jdk.internal.loader.ClassLoaders$PlatformClassLoader
// jdk.internal.loader.ClassLoaders$AppClassLoader
// with the following assumptions (based on the JDK core library source code):
//
// [a] these two loaders use the BuiltinClassLoader.loadClassOrNull() to
// load the named class.
// [b] BuiltinClassLoader.loadClassOrNull() first calls findLoadedClass(name).
// [c] At this point, if we can find the named class inside the
// shared_dictionary, we can perform further checks (see
// is_shared_class_visible_for_classloader() to ensure that this class
// was loaded by the same class loader during dump time.
//
// Given these assumptions, we intercept the findLoadedClass() call to invoke
// SystemDictionaryShared::find_or_load_shared_class() to load the shared class from
// the archive for the 2 built-in class loaders. This way,
// we can improve start-up because we avoid decoding the classfile,
// and avoid delegating to the parent loader.
//
// NOTE: there's a lot of assumption about the Java code. If any of that change, this
// needs to be redesigned.
InstanceKlass* SystemDictionaryShared::find_or_load_shared_class(
Symbol* name, Handle class_loader, TRAPS) {
InstanceKlass* k = NULL;
if (UseSharedSpaces) {
if (!has_platform_or_app_classes()) {
return NULL;
}
if (SystemDictionary::is_system_class_loader(class_loader()) ||
SystemDictionary::is_platform_class_loader(class_loader())) {
// Fix for 4474172; see evaluation for more details
class_loader = Handle(
THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader()));
ClassLoaderData *loader_data = register_loader(class_loader);
Dictionary* dictionary = loader_data->dictionary();
unsigned int d_hash = dictionary->compute_hash(name);
bool DoObjectLock = true;
if (is_parallelCapable(class_loader)) {
DoObjectLock = false;
}
// Make sure we are synchronized on the class loader before we proceed
//
// Note: currently, find_or_load_shared_class is called only from
// JVM_FindLoadedClass and used for PlatformClassLoader and AppClassLoader,
// which are parallel-capable loaders, so this lock is NOT taken.
Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
check_loader_lock_contention(lockObject, THREAD);
ObjectLocker ol(lockObject, THREAD, DoObjectLock);
{
MutexLocker mu(SystemDictionary_lock, THREAD);
InstanceKlass* check = find_class(d_hash, name, dictionary);
if (check != NULL) {
return check;
}
}
k = load_shared_class_for_builtin_loader(name, class_loader, THREAD);
if (k != NULL) {
define_instance_class(k, CHECK_NULL);
}
}
}
return k;
}
InstanceKlass* SystemDictionaryShared::load_shared_class_for_builtin_loader(
Symbol* class_name, Handle class_loader, TRAPS) {
assert(UseSharedSpaces, "must be");
InstanceKlass* ik = find_builtin_class(class_name);
if (ik != NULL) {
if ((ik->is_shared_app_class() &&
SystemDictionary::is_system_class_loader(class_loader())) ||
(ik->is_shared_platform_class() &&
SystemDictionary::is_platform_class_loader(class_loader()))) {
Handle protection_domain =
SystemDictionaryShared::init_security_info(class_loader, ik, CHECK_NULL);
return load_shared_class(ik, class_loader, protection_domain, NULL, THREAD);
}
}
return NULL;
}
void SystemDictionaryShared::oops_do(OopClosure* f) {
f->do_oop((oop*)&_shared_protection_domains);
f->do_oop((oop*)&_shared_jar_urls);
f->do_oop((oop*)&_shared_jar_manifests);
}
void SystemDictionaryShared::allocate_shared_protection_domain_array(int size, TRAPS) {
if (_shared_protection_domains == NULL) {
_shared_protection_domains = oopFactory::new_objArray(
SystemDictionary::ProtectionDomain_klass(), size, CHECK);
}
}
void SystemDictionaryShared::allocate_shared_jar_url_array(int size, TRAPS) {
if (_shared_jar_urls == NULL) {
_shared_jar_urls = oopFactory::new_objArray(
SystemDictionary::URL_klass(), size, CHECK);
}
}
void SystemDictionaryShared::allocate_shared_jar_manifest_array(int size, TRAPS) {
if (_shared_jar_manifests == NULL) {
_shared_jar_manifests = oopFactory::new_objArray(
SystemDictionary::Jar_Manifest_klass(), size, CHECK);
}
}
void SystemDictionaryShared::allocate_shared_data_arrays(int size, TRAPS) {
allocate_shared_protection_domain_array(size, CHECK);
allocate_shared_jar_url_array(size, CHECK);
allocate_shared_jar_manifest_array(size, CHECK);
}
// This function is called for loading only UNREGISTERED classes
InstanceKlass* SystemDictionaryShared::lookup_from_stream(Symbol* class_name,
Handle class_loader,
Handle protection_domain,
const ClassFileStream* cfs,
TRAPS) {
if (!UseSharedSpaces) {
return NULL;
}
if (class_name == NULL) { // don't do this for anonymous classes
return NULL;
}
if (class_loader.is_null() ||
SystemDictionary::is_system_class_loader(class_loader()) ||
SystemDictionary::is_platform_class_loader(class_loader())) {
// Do nothing for the BUILTIN loaders.
return NULL;
}
const RunTimeSharedClassInfo* record = find_record(&_unregistered_dictionary, &_dynamic_unregistered_dictionary, class_name);
if (record == NULL) {
return NULL;
}
int clsfile_size = cfs->length();
int clsfile_crc32 = ClassLoader::crc32(0, (const char*)cfs->buffer(), cfs->length());
if (!record->matches(clsfile_size, clsfile_crc32)) {
return NULL;
}
return acquire_class_for_current_thread(record->_klass, class_loader,
protection_domain, cfs,
THREAD);
}
InstanceKlass* SystemDictionaryShared::acquire_class_for_current_thread(
InstanceKlass *ik,
Handle class_loader,
Handle protection_domain,
const ClassFileStream *cfs,
TRAPS) {
ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
{
MutexLocker mu(SharedDictionary_lock, THREAD);
if (ik->class_loader_data() != NULL) {
// ik is already loaded (by this loader or by a different loader)
// or ik is being loaded by a different thread (by this loader or by a different loader)
return NULL;
}
// No other thread has acquired this yet, so give it to *this thread*
ik->set_class_loader_data(loader_data);
}
// No longer holding SharedDictionary_lock
// No need to lock, as <ik> can be held only by a single thread.
loader_data->add_class(ik);
// Load and check super/interfaces, restore unsharable info
InstanceKlass* shared_klass = load_shared_class(ik, class_loader, protection_domain,
cfs, THREAD);
if (shared_klass == NULL || HAS_PENDING_EXCEPTION) {
// TODO: clean up <ik> so it can be used again
return NULL;
}
return shared_klass;
}
static ResourceHashtable<
Symbol*, bool,
primitive_hash<Symbol*>,
primitive_equals<Symbol*>,
6661, // prime number
ResourceObj::C_HEAP> _loaded_unregistered_classes;
bool SystemDictionaryShared::add_unregistered_class(InstanceKlass* k, TRAPS) {
assert(DumpSharedSpaces, "only when dumping");
Symbol* name = k->name();
if (_loaded_unregistered_classes.get(name) != NULL) {
// We don't allow duplicated unregistered classes of the same name.
return false;
} else {
bool isnew = _loaded_unregistered_classes.put(name, true);
assert(isnew, "sanity");
MutexLocker mu_r(Compile_lock, THREAD); // add_to_hierarchy asserts this.
SystemDictionary::add_to_hierarchy(k, CHECK_0);
return true;
}
}
// This function is called to resolve the super/interfaces of shared classes for
// non-built-in loaders. E.g., ChildClass in the below example
// where "super:" (and optionally "interface:") have been specified.
//
// java/lang/Object id: 0
// Interface id: 2 super: 0 source: cust.jar
// ChildClass id: 4 super: 0 interfaces: 2 source: cust.jar
InstanceKlass* SystemDictionaryShared::dump_time_resolve_super_or_fail(
Symbol* child_name, Symbol* class_name, Handle class_loader,
Handle protection_domain, bool is_superclass, TRAPS) {
assert(DumpSharedSpaces, "only when dumping");
ClassListParser* parser = ClassListParser::instance();
if (parser == NULL) {
// We're still loading the well-known classes, before the ClassListParser is created.
return NULL;
}
if (child_name->equals(parser->current_class_name())) {
// When this function is called, all the numbered super and interface types
// must have already been loaded. Hence this function is never recursively called.
if (is_superclass) {
return parser->lookup_super_for_current_class(class_name);
} else {
return parser->lookup_interface_for_current_class(class_name);
}
} else {
// The VM is not trying to resolve a super type of parser->current_class_name().
// Instead, it's resolving an error class (because parser->current_class_name() has
// failed parsing or verification). Don't do anything here.
return NULL;
}
}
DumpTimeSharedClassInfo* SystemDictionaryShared::find_or_allocate_info_for(InstanceKlass* k) {
MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
if (_dumptime_table == NULL) {
_dumptime_table = new (ResourceObj::C_HEAP, mtClass)DumpTimeSharedClassTable();
}
return _dumptime_table->find_or_allocate_info_for(k);
}
void SystemDictionaryShared::set_shared_class_misc_info(InstanceKlass* k, ClassFileStream* cfs) {
Arguments::assert_is_dumping_archive();
assert(!is_builtin(k), "must be unregistered class");
DumpTimeSharedClassInfo* info = find_or_allocate_info_for(k);
info->_clsfile_size = cfs->length();
info->_clsfile_crc32 = ClassLoader::crc32(0, (const char*)cfs->buffer(), cfs->length());
}
void SystemDictionaryShared::init_dumptime_info(InstanceKlass* k) {
(void)find_or_allocate_info_for(k);
}
void SystemDictionaryShared::remove_dumptime_info(InstanceKlass* k) {
MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
DumpTimeSharedClassInfo* p = _dumptime_table->get(k);
if (p == NULL) {
return;
}
if (p->_verifier_constraints != NULL) {
for (int i = 0; i < p->_verifier_constraints->length(); i++) {
DumpTimeSharedClassInfo::DTConstraint constraint = p->_verifier_constraints->at(i);
if (constraint._name != NULL ) {
constraint._name->decrement_refcount();
}
if (constraint._from_name != NULL ) {
constraint._from_name->decrement_refcount();
}
}
FREE_C_HEAP_ARRAY(DTConstraint, p->_verifier_constraints);
p->_verifier_constraints = NULL;
}
FREE_C_HEAP_ARRAY(char, p->_verifier_constraint_flags);
p->_verifier_constraint_flags = NULL;
_dumptime_table->remove(k);
}
bool SystemDictionaryShared::is_jfr_event_class(InstanceKlass *k) {
while (k) {
if (k->name()->equals("jdk/internal/event/Event")) {
return true;
}
k = k->java_super();
}
return false;
}
void SystemDictionaryShared::warn_excluded(InstanceKlass* k, const char* reason) {
ResourceMark rm;
log_warning(cds)("Skipping %s: %s", k->name()->as_C_string(), reason);
}
bool SystemDictionaryShared::should_be_excluded(InstanceKlass* k) {
if (k->class_loader_data()->is_unsafe_anonymous()) {
warn_excluded(k, "Unsafe anonymous class");
return true; // unsafe anonymous classes are not archived, skip
}
if (k->is_in_error_state()) {
warn_excluded(k, "In error state");
return true;
}
if (k->shared_classpath_index() < 0 && is_builtin(k)) {
// These are classes loaded from unsupported locations (such as those loaded by JVMTI native
// agent during dump time).
warn_excluded(k, "Unsupported location");
return true;
}
if (k->signers() != NULL) {
// We cannot include signed classes in the archive because the certificates
// used during dump time may be different than those used during
// runtime (due to expiration, etc).
warn_excluded(k, "Signed JAR");
return true;
}
if (is_jfr_event_class(k)) {
// We cannot include JFR event classes because they need runtime-specific
// instrumentation in order to work with -XX:FlightRecorderOptions=retransform=false.
// There are only a small number of these classes, so it's not worthwhile to
// support them and make CDS more complicated.
warn_excluded(k, "JFR event class");
return true;
}
if (k->init_state() < InstanceKlass::linked) {
// In static dumping, we will attempt to link all classes. Those that fail to link will
// be marked as in error state.
assert(DynamicDumpSharedSpaces, "must be");
// TODO -- rethink how this can be handled.
// We should try to link ik, however, we can't do it here because
// 1. We are at VM exit
// 2. linking a class may cause other classes to be loaded, which means
// a custom ClassLoader.loadClass() may be called, at a point where the
// class loader doesn't expect it.
warn_excluded(k, "Not linked");
return true;
}
if (k->major_version() < 50 /*JAVA_6_VERSION*/) {
ResourceMark rm;
log_warning(cds)("Pre JDK 6 class not supported by CDS: %u.%u %s",
k->major_version(), k->minor_version(), k->name()->as_C_string());
return true;
}
InstanceKlass* super = k->java_super();
if (super != NULL && should_be_excluded(super)) {
ResourceMark rm;
log_warning(cds)("Skipping %s: super class %s is excluded", k->name()->as_C_string(), super->name()->as_C_string());
return true;
}
Array<InstanceKlass*>* interfaces = k->local_interfaces();
int len = interfaces->length();
for (int i = 0; i < len; i++) {
InstanceKlass* intf = interfaces->at(i);
if (should_be_excluded(intf)) {
log_warning(cds)("Skipping %s: interface %s is excluded", k->name()->as_C_string(), intf->name()->as_C_string());
return true;
}
}
return false;
}
// k is a class before relocating by ArchiveCompactor
void SystemDictionaryShared::validate_before_archiving(InstanceKlass* k) {
ResourceMark rm;
const char* name = k->name()->as_C_string();
DumpTimeSharedClassInfo* info = _dumptime_table->get(k);
assert(_no_class_loading_should_happen, "class loading must be disabled");
guarantee(info != NULL, "Class %s must be entered into _dumptime_table", name);
guarantee(!info->is_excluded(), "Should not attempt to archive excluded class %s", name);
if (is_builtin(k)) {
guarantee(k->loader_type() != 0,
"Class loader type must be set for BUILTIN class %s", name);
} else {
guarantee(k->loader_type() == 0,
"Class loader type must not be set for UNREGISTERED class %s", name);
}
}
class ExcludeDumpTimeSharedClasses : StackObj {
public:
bool do_entry(InstanceKlass* k, DumpTimeSharedClassInfo& info) {
if (SystemDictionaryShared::should_be_excluded(k)) {
info.set_excluded();
}
return true; // keep on iterating
}
};
void SystemDictionaryShared::check_excluded_classes() {
ExcludeDumpTimeSharedClasses excl;
_dumptime_table->iterate(&excl);
_dumptime_table->update_counts();
}
bool SystemDictionaryShared::is_excluded_class(InstanceKlass* k) {
assert(_no_class_loading_should_happen, "sanity");
Arguments::assert_is_dumping_archive();
return find_or_allocate_info_for(k)->is_excluded();
}
class IterateDumpTimeSharedClassTable : StackObj {
MetaspaceClosure *_it;
public:
IterateDumpTimeSharedClassTable(MetaspaceClosure* it) : _it(it) {}
bool do_entry(InstanceKlass* k, DumpTimeSharedClassInfo& info) {
if (!info.is_excluded()) {
info.metaspace_pointers_do(_it);
}
return true; // keep on iterating
}
};
void SystemDictionaryShared::dumptime_classes_do(class MetaspaceClosure* it) {
IterateDumpTimeSharedClassTable iter(it);
_dumptime_table->iterate(&iter);
}
bool SystemDictionaryShared::add_verification_constraint(InstanceKlass* k, Symbol* name,
Symbol* from_name, bool from_field_is_protected, bool from_is_array, bool from_is_object) {
Arguments::assert_is_dumping_archive();
DumpTimeSharedClassInfo* info = find_or_allocate_info_for(k);
info->add_verification_constraint(k, name, from_name, from_field_is_protected,
from_is_array, from_is_object);
if (DynamicDumpSharedSpaces) {
// For dynamic dumping, we can resolve all the constraint classes for all class loaders during
// the initial run prior to creating the archive before vm exit. We will also perform verification
// check when running with the archive.
return false;
} else {
if (is_builtin(k)) {
// For builtin class loaders, we can try to complete the verification check at dump time,
// because we can resolve all the constraint classes. We will also perform verification check
// when running with the archive.
return false;
} else {
// For non-builtin class loaders, we cannot complete the verification check at dump time,
// because at dump time we don't know how to resolve classes for such loaders.
return true;
}
}
}
void DumpTimeSharedClassInfo::add_verification_constraint(InstanceKlass* k, Symbol* name,
Symbol* from_name, bool from_field_is_protected, bool from_is_array, bool from_is_object) {
if (_verifier_constraints == NULL) {
_verifier_constraints = new(ResourceObj::C_HEAP, mtClass) GrowableArray<DTConstraint>(4, true, mtClass);
}
if (_verifier_constraint_flags == NULL) {
_verifier_constraint_flags = new(ResourceObj::C_HEAP, mtClass) GrowableArray<char>(4, true, mtClass);
}
GrowableArray<DTConstraint>* vc_array = _verifier_constraints;
for (int i = 0; i < vc_array->length(); i++) {
DTConstraint* p = vc_array->adr_at(i);
if (name == p->_name && from_name == p->_from_name) {
return;
}
}
DTConstraint cons(name, from_name);
vc_array->append(cons);
GrowableArray<char>* vcflags_array = _verifier_constraint_flags;
char c = 0;
c |= from_field_is_protected ? SystemDictionaryShared::FROM_FIELD_IS_PROTECTED : 0;
c |= from_is_array ? SystemDictionaryShared::FROM_IS_ARRAY : 0;
c |= from_is_object ? SystemDictionaryShared::FROM_IS_OBJECT : 0;
vcflags_array->append(c);
if (log_is_enabled(Trace, cds, verification)) {
ResourceMark rm;
log_trace(cds, verification)("add_verification_constraint: %s: %s must be subclass of %s [0x%x]",
k->external_name(), from_name->as_klass_external_name(),
name->as_klass_external_name(), c);
}
}
void SystemDictionaryShared::check_verification_constraints(InstanceKlass* klass,
TRAPS) {
assert(!DumpSharedSpaces && UseSharedSpaces, "called at run time with CDS enabled only");
RunTimeSharedClassInfo* record = RunTimeSharedClassInfo::get_for(klass);
int length = record->_num_constraints;
if (length > 0) {
for (int i = 0; i < length; i++) {
Symbol* name = record->get_constraint_name(i);
Symbol* from_name = record->get_constraint_from_name(i);
char c = record->get_constraint_flag(i);
if (log_is_enabled(Trace, cds, verification)) {
ResourceMark rm(THREAD);
log_trace(cds, verification)("check_verification_constraint: %s: %s must be subclass of %s [0x%x]",
klass->external_name(), from_name->as_klass_external_name(),
name->as_klass_external_name(), c);
}
bool from_field_is_protected = (c & SystemDictionaryShared::FROM_FIELD_IS_PROTECTED) ? true : false;
bool from_is_array = (c & SystemDictionaryShared::FROM_IS_ARRAY) ? true : false;
bool from_is_object = (c & SystemDictionaryShared::FROM_IS_OBJECT) ? true : false;
bool ok = VerificationType::resolve_and_check_assignability(klass, name,
from_name, from_field_is_protected, from_is_array, from_is_object, CHECK);
if (!ok) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print_cr("Bad type on operand stack");
ss.print_cr("Exception Details:");
ss.print_cr(" Location:\n %s", klass->name()->as_C_string());
ss.print_cr(" Reason:\n Type '%s' is not assignable to '%s'",
from_name->as_quoted_ascii(), name->as_quoted_ascii());
THROW_MSG(vmSymbols::java_lang_VerifyError(), ss.as_string());
}
}
}
}
class EstimateSizeForArchive : StackObj {
size_t _shared_class_info_size;
int _num_builtin_klasses;
int _num_unregistered_klasses;
public:
EstimateSizeForArchive() {
_shared_class_info_size = 0;
_num_builtin_klasses = 0;
_num_unregistered_klasses = 0;
}
bool do_entry(InstanceKlass* k, DumpTimeSharedClassInfo& info) {
if (!info.is_excluded()) {
size_t byte_size = RunTimeSharedClassInfo::byte_size(info._klass, info.num_constraints());
_shared_class_info_size += align_up(byte_size, BytesPerWord);
}
return true; // keep on iterating
}
size_t total() {
return _shared_class_info_size;
}
};
size_t SystemDictionaryShared::estimate_size_for_archive() {
EstimateSizeForArchive est;
_dumptime_table->iterate(&est);
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