/* * Copyright (c) 1997, 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. * */ #ifndef SHARE_MEMORY_UNIVERSE_HPP #define SHARE_MEMORY_UNIVERSE_HPP #include "gc/shared/verifyOption.hpp" #include "oops/array.hpp" #include "oops/oopHandle.hpp" #include "runtime/handles.hpp" #include "utilities/growableArray.hpp" // Universe is a name space holding known system classes and objects in the VM. // // Loaded classes are accessible through the SystemDictionary. // // The object heap is allocated and accessed through Universe, and various allocation // support is provided. Allocation by the interpreter and compiled code is done inline // and bails out to Scavenge::invoke_and_allocate. class CollectedHeap; class DeferredObjAllocEvent; class OopStorage; // A helper class for caching a Method* when the user of the cache // only cares about the latest version of the Method*. This cache safely // interacts with the RedefineClasses API. class LatestMethodCache : public CHeapObj { // We save the Klass* and the idnum of Method* in order to get // the current cached Method*. private: Klass* _klass; int _method_idnum; public: LatestMethodCache() { _klass = NULL; _method_idnum = -1; } ~LatestMethodCache() { _klass = NULL; _method_idnum = -1; } void init(Klass* k, Method* m); Klass* klass() const { return _klass; } int method_idnum() const { return _method_idnum; } Method* get_method(); // CDS support. Replace the klass in this with the archive version // could use this for Enhanced Class Redefinition also. void serialize(SerializeClosure* f) { f->do_ptr((void**)&_klass); } void metaspace_pointers_do(MetaspaceClosure* it); }; class Universe: AllStatic { // Ugh. Universe is much too friendly. friend class MarkSweep; friend class oopDesc; friend class ClassLoader; friend class SystemDictionary; friend class ReservedHeapSpace; friend class VMStructs; friend class VM_PopulateDumpSharedSpace; friend class Metaspace; friend class MetaspaceShared; friend jint universe_init(); friend void universe2_init(); friend bool universe_post_init(); friend void universe_post_module_init(); private: // Known classes in the VM static Klass* _typeArrayKlassObjs[T_LONG+1]; static Klass* _objectArrayKlassObj; // Known objects in the VM // Primitive objects static oop _int_mirror; static oop _float_mirror; static oop _double_mirror; static oop _byte_mirror; static oop _bool_mirror; static oop _char_mirror; static oop _long_mirror; static oop _short_mirror; static oop _void_mirror; static OopHandle _main_thread_group; // Reference to the main thread group object static OopHandle _system_thread_group; // Reference to the system thread group object static OopHandle _the_empty_class_array; // Canonicalized obj array of type java.lang.Class static OopHandle _the_null_string; // A cache of "null" as a Java string static OopHandle _the_min_jint_string; // A cache of "-2147483648" as a Java string static OopHandle _the_null_sentinel; // A unique object pointer unused except as a sentinel for null. // preallocated error objects (no backtrace) static OopHandle _out_of_memory_errors; // preallocated cause message for delayed StackOverflowError static OopHandle _delayed_stack_overflow_error_message; static LatestMethodCache* _finalizer_register_cache; // static method for registering finalizable objects static LatestMethodCache* _loader_addClass_cache; // method for registering loaded classes in class loader vector static LatestMethodCache* _throw_illegal_access_error_cache; // Unsafe.throwIllegalAccessError() method static LatestMethodCache* _throw_no_such_method_error_cache; // Unsafe.throwNoSuchMethodError() method static LatestMethodCache* _do_stack_walk_cache; // method for stack walker callback static Array* _the_empty_int_array; // Canonicalized int array static Array* _the_empty_short_array; // Canonicalized short array static Array* _the_empty_klass_array; // Canonicalized klass array static Array* _the_empty_instance_klass_array; // Canonicalized instance klass array static Array* _the_empty_method_array; // Canonicalized method array static Array* _the_array_interfaces_array; // array of preallocated error objects with backtrace static OopHandle _preallocated_out_of_memory_error_array; // number of preallocated error objects available for use static volatile jint _preallocated_out_of_memory_error_avail_count; static OopHandle _null_ptr_exception_instance; // preallocated exception object static OopHandle _arithmetic_exception_instance; // preallocated exception object static OopHandle _virtual_machine_error_instance; // preallocated exception object // References waiting to be transferred to the ReferenceHandler static oop _reference_pending_list; // The particular choice of collected heap. static CollectedHeap* _collectedHeap; static intptr_t _non_oop_bits; // array of dummy objects used with +FullGCAlot debug_only(static OopHandle _fullgc_alot_dummy_array;) debug_only(static int _fullgc_alot_dummy_next;) // Compiler/dispatch support static int _base_vtable_size; // Java vtbl size of klass Object (in words) // Initialization static bool _bootstrapping; // true during genesis static bool _module_initialized; // true after call_initPhase2 called static bool _fully_initialized; // true after universe_init and initialize_vtables called // the array of preallocated errors with backtraces static objArrayOop preallocated_out_of_memory_errors(); static objArrayOop out_of_memory_errors(); // generate an out of memory error; if possible using an error with preallocated backtrace; // otherwise return the given default error. static oop gen_out_of_memory_error(oop default_err); // Historic gc information static size_t _heap_capacity_at_last_gc; static size_t _heap_used_at_last_gc; static OopStorage* _vm_weak; static OopStorage* _vm_global; static jint initialize_heap(); static void initialize_tlab(); static void initialize_basic_type_mirrors(TRAPS); static void fixup_mirrors(TRAPS); static void reinitialize_vtable_of(Klass* k, TRAPS); static void reinitialize_vtables(TRAPS); static void reinitialize_itables(TRAPS); static void compute_base_vtable_size(); // compute vtable size of class Object static void genesis(TRAPS); // Create the initial world // Mirrors for primitive classes (created eagerly) static oop check_mirror(oop m) { assert(m != NULL, "mirror not initialized"); return m; } // Debugging static int _verify_count; // number of verifies done // True during call to verify(). Should only be set/cleared in verify(). static bool _verify_in_progress; static long verify_flags; static uintptr_t _verify_oop_mask; static uintptr_t _verify_oop_bits; public: static void calculate_verify_data(HeapWord* low_boundary, HeapWord* high_boundary) PRODUCT_RETURN; // Known classes in the VM static Klass* boolArrayKlassObj() { return typeArrayKlassObj(T_BOOLEAN); } static Klass* byteArrayKlassObj() { return typeArrayKlassObj(T_BYTE); } static Klass* charArrayKlassObj() { return typeArrayKlassObj(T_CHAR); } static Klass* intArrayKlassObj() { return typeArrayKlassObj(T_INT); } static Klass* shortArrayKlassObj() { return typeArrayKlassObj(T_SHORT); } static Klass* longArrayKlassObj() { return typeArrayKlassObj(T_LONG); } static Klass* floatArrayKlassObj() { return typeArrayKlassObj(T_FLOAT); } static Klass* doubleArrayKlassObj() { return typeArrayKlassObj(T_DOUBLE); } static Klass* objectArrayKlassObj() { return _objectArrayKlassObj; } static Klass* typeArrayKlassObj(BasicType t) { assert((uint)t >= T_BOOLEAN, "range check for type: %s", type2name(t)); assert((uint)t < T_LONG+1, "range check for type: %s", type2name(t)); assert(_typeArrayKlassObjs[t] != NULL, "domain check"); return _typeArrayKlassObjs[t]; } // Known objects in the VM static oop int_mirror() { return check_mirror(_int_mirror); } static oop float_mirror() { return check_mirror(_float_mirror); } static oop double_mirror() { return check_mirror(_double_mirror); } static oop byte_mirror() { return check_mirror(_byte_mirror); } static oop bool_mirror() { return check_mirror(_bool_mirror); } static oop char_mirror() { return check_mirror(_char_mirror); } static oop long_mirror() { return check_mirror(_long_mirror); } static oop short_mirror() { return check_mirror(_short_mirror); } static oop void_mirror() { return check_mirror(_void_mirror); } static void set_int_mirror(oop m) { _int_mirror = m; } static void set_float_mirror(oop m) { _float_mirror = m; } static void set_double_mirror(oop m) { _double_mirror = m; } static void set_byte_mirror(oop m) { _byte_mirror = m; } static void set_bool_mirror(oop m) { _bool_mirror = m; } static void set_char_mirror(oop m) { _char_mirror = m; } static void set_long_mirror(oop m) { _long_mirror = m; } static void set_short_mirror(oop m) { _short_mirror = m; } static void set_void_mirror(oop m) { _void_mirror = m; } // table of same static oop _mirrors[T_VOID+1]; static oop java_mirror(BasicType t) { assert((uint)t < T_VOID+1, "range check"); return check_mirror(_mirrors[t]); } static oop main_thread_group(); static void set_main_thread_group(oop group); static oop system_thread_group(); static void set_system_thread_group(oop group); static objArrayOop the_empty_class_array (); static oop the_null_string(); static oop the_min_jint_string(); static oop null_ptr_exception_instance(); static oop arithmetic_exception_instance(); static oop virtual_machine_error_instance(); static oop vm_exception() { return virtual_machine_error_instance(); } static Array* the_array_interfaces_array() { return _the_array_interfaces_array; } static Method* finalizer_register_method() { return _finalizer_register_cache->get_method(); } static Method* loader_addClass_method() { return _loader_addClass_cache->get_method(); } static Method* throw_illegal_access_error() { return _throw_illegal_access_error_cache->get_method(); } static Method* throw_no_such_method_error() { return _throw_no_such_method_error_cache->get_method(); } static Method* do_stack_walk_method() { return _do_stack_walk_cache->get_method(); } static oop the_null_sentinel(); static address the_null_sentinel_addr() { return (address) &_the_null_sentinel; } // Function to initialize these static void initialize_known_methods(TRAPS); static void create_preallocated_out_of_memory_errors(TRAPS); // Reference pending list manipulation. Access is protected by // Heap_lock. The getter, setter and predicate require the caller // owns the lock. Swap is used by parallel non-concurrent reference // processing threads, where some higher level controller owns // Heap_lock, so requires the lock is locked, but not necessarily by // the current thread. static oop reference_pending_list(); static void clear_reference_pending_list(); static bool has_reference_pending_list(); static oop swap_reference_pending_list(oop list); static Array* the_empty_int_array() { return _the_empty_int_array; } static Array* the_empty_short_array() { return _the_empty_short_array; } static Array* the_empty_method_array() { return _the_empty_method_array; } static Array* the_empty_klass_array() { return _the_empty_klass_array; } static Array* the_empty_instance_klass_array() { return _the_empty_instance_klass_array; } // OutOfMemoryError support. Returns an error with the required message. The returned error // may or may not have a backtrace. If error has a backtrace then the stack trace is already // filled in. static oop out_of_memory_error_java_heap(); static oop out_of_memory_error_c_heap(); static oop out_of_memory_error_metaspace(); static oop out_of_memory_error_class_metaspace(); static oop out_of_memory_error_array_size(); static oop out_of_memory_error_gc_overhead_limit(); static oop out_of_memory_error_realloc_objects(); // Throw default _out_of_memory_error_retry object as it will never propagate out of the VM static oop out_of_memory_error_retry(); static oop delayed_stack_overflow_error_message(); // The particular choice of collected heap. static CollectedHeap* heap() { return _collectedHeap; } // Reserve Java heap and determine CompressedOops mode static ReservedHeapSpace reserve_heap(size_t heap_size, size_t alignment); // Historic gc information static size_t get_heap_free_at_last_gc() { return _heap_capacity_at_last_gc - _heap_used_at_last_gc; } static size_t get_heap_used_at_last_gc() { return _heap_used_at_last_gc; } static void update_heap_info_at_gc(); // Global OopStorages static OopStorage* vm_weak(); static OopStorage* vm_global(); static void oopstorage_init(); // Testers static bool is_bootstrapping() { return _bootstrapping; } static bool is_module_initialized() { return _module_initialized; } static bool is_fully_initialized() { return _fully_initialized; } static bool on_page_boundary(void* addr); static bool should_fill_in_stack_trace(Handle throwable); static void check_alignment(uintx size, uintx alignment, const char* name); // Iteration // Apply "f" to the addresses of all the direct heap pointers maintained // as static fields of "Universe". static void oops_do(OopClosure* f); // CDS support static void serialize(SerializeClosure* f); // Apply "f" to all klasses for basic types (classes not present in // SystemDictionary). static void basic_type_classes_do(void f(Klass*)); static void basic_type_classes_do(KlassClosure* closure); static void metaspace_pointers_do(MetaspaceClosure* it); // Debugging enum VERIFY_FLAGS { Verify_Threads = 1, Verify_Heap = 2, Verify_SymbolTable = 4, Verify_StringTable = 8, Verify_CodeCache = 16, Verify_SystemDictionary = 32, Verify_ClassLoaderDataGraph = 64, Verify_MetaspaceUtils = 128, Verify_JNIHandles = 256, Verify_CodeCacheOops = 512, Verify_ResolvedMethodTable = 1024, Verify_All = -1 }; static void initialize_verify_flags(); static bool should_verify_subset(uint subset); static bool verify_in_progress() { return _verify_in_progress; } static void verify(VerifyOption option, const char* prefix); static void verify(const char* prefix) { verify(VerifyOption_Default, prefix); } static void verify() { verify(""); } static int verify_count() { return _verify_count; } static void print_on(outputStream* st); static void print_heap_at_SIGBREAK(); static void print_heap_before_gc(); static void print_heap_after_gc(); // Change the number of dummy objects kept reachable by the full gc dummy // array; this should trigger relocation in a sliding compaction collector. debug_only(static bool release_fullgc_alot_dummy();) // The non-oop pattern (see compiledIC.hpp, etc) static void* non_oop_word(); // Oop verification (see MacroAssembler::verify_oop) static uintptr_t verify_oop_mask() PRODUCT_RETURN0; static uintptr_t verify_oop_bits() PRODUCT_RETURN0; static uintptr_t verify_mark_bits() PRODUCT_RETURN0; static uintptr_t verify_mark_mask() PRODUCT_RETURN0; // Compiler support static int base_vtable_size() { return _base_vtable_size; } }; #endif // SHARE_MEMORY_UNIVERSE_HPP