/*

 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_VM_MEMORY_METASPACESHARED_HPP

#define SHARE_VM_MEMORY_METASPACESHARED_HPP

#include "classfile/compactHashtable.hpp"

#include "memory/allocation.hpp"

#include "memory/memRegion.hpp"

#include "memory/virtualspace.hpp"

#include "oops/oop.hpp"

#include "utilities/exceptions.hpp"

#include "utilities/macros.hpp"

#include "utilities/resourceHash.hpp"

#define MAX_SHARED_DELTA                (0x7FFFFFFF)

class FileMapInfo;

class MetaspaceSharedStats {

public:

  MetaspaceSharedStats() {

    memset(this, 0, sizeof(*this));

  }

  CompactHashtableStats symbol;

  CompactHashtableStats string;

};

// Class Data Sharing Support

class MetaspaceShared : AllStatic {

  // CDS support

  static ReservedSpace _shared_rs;

  static VirtualSpace _shared_vs;

  static int _max_alignment;

  static MetaspaceSharedStats _stats;

  static bool _has_error_classes;

  static bool _archive_loading_failed;

  static bool _remapped_readwrite;

  static bool _open_archive_heap_region_mapped;

  static address _cds_i2i_entry_code_buffers;

  static size_t  _cds_i2i_entry_code_buffers_size;

  static size_t  _core_spaces_size;

 public:

  enum {

    // core archive spaces

    mc = 0,  // miscellaneous code for method trampolines

    rw = 1,  // read-write shared space in the heap

    ro = 2,  // read-only shared space in the heap

    md = 3,  // miscellaneous data for initializing tables, etc.

    num_core_spaces = 4, // number of non-string regions

    // optional mapped spaces

    // Currently it only contains class file data.

    od = num_core_spaces,

    num_non_heap_spaces = od + 1,

    // mapped java heap regions

    first_string = od + 1, // index of first string region

    max_strings = 2, // max number of string regions in string space

    first_open_archive_heap_region = first_string + max_strings,

    max_open_archive_heap_region = 2,

    last_valid_region = first_open_archive_heap_region + max_open_archive_heap_region - 1,

    n_regions =  last_valid_region + 1 // total number of regions

  };

  static void prepare_for_dumping() NOT_CDS_RETURN;

  static void preload_and_dump(TRAPS) NOT_CDS_RETURN;

  static int preload_classes(const char * class_list_path,

                             TRAPS) NOT_CDS_RETURN_(0);

#if INCLUDE_CDS_JAVA_HEAP

 private:

  static bool obj_equals(oop const& p1, oop const& p2) {

    return p1 == p2;

  }

  static unsigned obj_hash(oop const& p);

  typedef ResourceHashtable<oop, oop,

      MetaspaceShared::obj_hash,

      MetaspaceShared::obj_equals,

      15889, // prime number

      ResourceObj::C_HEAP> ArchivedObjectCache;

  static ArchivedObjectCache* _archive_object_cache;

 public:

  static ArchivedObjectCache* archive_object_cache() {

    return _archive_object_cache;

  }

  static oop find_archived_heap_object(oop obj);

  static oop archive_heap_object(oop obj, Thread* THREAD);

  static void archive_klass_objects(Thread* THREAD);

#endif

  static bool is_archive_object(oop p) NOT_CDS_JAVA_HEAP_RETURN_(false);

  static bool is_heap_object_archiving_allowed() {

    CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)

    NOT_CDS_JAVA_HEAP(return false;)

  }

  static void create_archive_object_cache() {

    CDS_JAVA_HEAP_ONLY(_archive_object_cache = new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache(););

  }

  static void destroy_archive_object_cache() {

    CDS_JAVA_HEAP_ONLY(delete _archive_object_cache; _archive_object_cache = NULL;);

  }

  static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;

  static void dump_closed_archive_heap_objects(GrowableArray<MemRegion> * closed_archive) NOT_CDS_JAVA_HEAP_RETURN;

  static void dump_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive) NOT_CDS_JAVA_HEAP_RETURN;

  static void set_open_archive_heap_region_mapped() {

    CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true);

    NOT_CDS_JAVA_HEAP_RETURN;

  }

  static bool open_archive_heap_region_mapped() {

    CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped);

    NOT_CDS_JAVA_HEAP_RETURN_(false);

  }

  static ReservedSpace* shared_rs() {

    CDS_ONLY(return &_shared_rs);

    NOT_CDS(return NULL);

  }

  static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN;

  static size_t core_spaces_size() {

    return _core_spaces_size;

  }

  static void initialize_dumptime_shared_and_meta_spaces() NOT_CDS_RETURN;

  static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;

  static void post_initialize(TRAPS) NOT_CDS_RETURN;

  // Delta of this object from the bottom of the archive.

  static uintx object_delta(void* obj) {

    assert(DumpSharedSpaces, "supported only for dumping");

    assert(shared_rs()->contains(obj), "must be");

    address base_address = address(shared_rs()->base());

    uintx delta = address(obj) - base_address;

    return delta;

  }

  static void set_archive_loading_failed() {

    _archive_loading_failed = true;

  }

  static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);

  static void initialize_shared_spaces() NOT_CDS_RETURN;

  // Return true if given address is in the shared metaspace regions (i.e., excluding any

  // mapped shared heap regions.)

  static bool is_in_shared_metaspace(const void* p) {

    // If no shared metaspace regions are mapped, MetaspceObj::_shared_metaspace_{base,top} will

    // both be NULL and all values of p will be rejected quickly.

    return (p < MetaspaceObj::_shared_metaspace_top && p >= MetaspaceObj::_shared_metaspace_base);

  }

  // Return true if given address is in the shared region corresponding to the idx

  static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);

  static bool is_heap_region(int idx) {

    CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string &&

                               idx < MetaspaceShared::first_open_archive_heap_region +

                                     MetaspaceShared::max_open_archive_heap_region));

    NOT_CDS_JAVA_HEAP_RETURN_(false);

  }

  static bool is_string_region(int idx) {

    CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string &&

                               idx < MetaspaceShared::first_string + MetaspaceShared::max_strings));

    NOT_CDS_JAVA_HEAP_RETURN_(false);

  }

  static bool is_open_archive_heap_region(int idx) {

    CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_open_archive_heap_region &&

                               idx < MetaspaceShared::first_open_archive_heap_region +

                                     MetaspaceShared::max_open_archive_heap_region));

    NOT_CDS_JAVA_HEAP_RETURN_(false);

  }

  static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false);

  static void allocate_cpp_vtable_clones();

  static intptr_t* clone_cpp_vtables(intptr_t* p);

  static void zero_cpp_vtable_clones_for_writing();

  static void patch_cpp_vtable_pointers();

  static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false);

  static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;

  static MetaspaceSharedStats* stats() {

    return &_stats;

  }

  static void report_out_of_space(const char* name, size_t needed_bytes);

  // JVM/TI RedefineClasses() support:

  // Remap the shared readonly space to shared readwrite, private if

  // sharing is enabled. Simply returns true if sharing is not enabled

  // or if the remapping has already been done by a prior call.

  static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);

  static bool remapped_readwrite() {

    CDS_ONLY(return _remapped_readwrite);

    NOT_CDS(return false);

  }

  static bool try_link_class(InstanceKlass* ik, TRAPS);

  static void link_and_cleanup_shared_classes(TRAPS);

  static void check_shared_class_loader_type(InstanceKlass* ik);

  // Allocate a block of memory from the "mc", "ro", or "rw" regions.

  static char* misc_code_space_alloc(size_t num_bytes);

  static char* read_only_space_alloc(size_t num_bytes);

  static char* read_only_space_top();

  template <typename T>

  static Array<T>* new_ro_array(int length) {

#if INCLUDE_CDS

    size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));

    Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size);

    array->initialize(length);

    return array;

#else

    return NULL;

#endif

  }

  static address cds_i2i_entry_code_buffers(size_t total_size);

  static address cds_i2i_entry_code_buffers() {

    return _cds_i2i_entry_code_buffers;

  }

  static size_t cds_i2i_entry_code_buffers_size() {

    return _cds_i2i_entry_code_buffers_size;

  }

  static void relocate_klass_ptr(oop o);

  static Klass* get_relocated_klass(Klass *k);

private:

  static void read_extra_data(const char* filename, TRAPS) NOT_CDS_RETURN;

};

#endif // SHARE_VM_MEMORY_METASPACESHARED_HPP