1 /*
   2  * Copyright (c) 2012, 2020, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "jvm.h"
  27 #include "classfile/classLoaderDataGraph.hpp"
  28 #include "classfile/classListParser.hpp"
  29 #include "classfile/classLoaderExt.hpp"
  30 #include "classfile/dictionary.hpp"
  31 #include "classfile/loaderConstraints.hpp"
  32 #include "classfile/javaClasses.inline.hpp"
  33 #include "classfile/placeholders.hpp"
  34 #include "classfile/symbolTable.hpp"
  35 #include "classfile/stringTable.hpp"
  36 #include "classfile/systemDictionary.hpp"
  37 #include "classfile/systemDictionaryShared.hpp"
  38 #include "code/codeCache.hpp"
  39 #include "gc/shared/softRefPolicy.hpp"
  40 #include "interpreter/bytecodeStream.hpp"
  41 #include "interpreter/bytecodes.hpp"
  42 #include "logging/log.hpp"
  43 #include "logging/logMessage.hpp"
  44 #include "memory/archiveUtils.inline.hpp"
  45 #include "memory/dynamicArchive.hpp"
  46 #include "memory/filemap.hpp"
  47 #include "memory/heapShared.inline.hpp"
  48 #include "memory/metaspace.hpp"
  49 #include "memory/metaspaceClosure.hpp"
  50 #include "memory/metaspaceShared.hpp"
  51 #include "memory/resourceArea.hpp"
  52 #include "memory/universe.hpp"
  53 #include "oops/compressedOops.inline.hpp"
  54 #include "oops/instanceClassLoaderKlass.hpp"
  55 #include "oops/instanceMirrorKlass.hpp"
  56 #include "oops/instanceRefKlass.hpp"
  57 #include "oops/methodData.hpp"
  58 #include "oops/objArrayKlass.hpp"
  59 #include "oops/objArrayOop.hpp"
  60 #include "oops/oop.inline.hpp"
  61 #include "oops/typeArrayKlass.hpp"
  62 #include "prims/jvmtiRedefineClasses.hpp"
  63 #include "runtime/handles.inline.hpp"
  64 #include "runtime/os.hpp"
  65 #include "runtime/safepointVerifiers.hpp"
  66 #include "runtime/signature.hpp"
  67 #include "runtime/timerTrace.hpp"
  68 #include "runtime/vmThread.hpp"
  69 #include "runtime/vmOperations.hpp"
  70 #include "utilities/align.hpp"
  71 #include "utilities/bitMap.inline.hpp"
  72 #include "utilities/ostream.hpp"
  73 #include "utilities/defaultStream.hpp"
  74 #include "utilities/hashtable.inline.hpp"
  75 #if INCLUDE_G1GC
  76 #include "gc/g1/g1CollectedHeap.hpp"
  77 #endif
  78 
  79 ReservedSpace MetaspaceShared::_shared_rs;
  80 VirtualSpace MetaspaceShared::_shared_vs;
  81 ReservedSpace MetaspaceShared::_symbol_rs;
  82 VirtualSpace MetaspaceShared::_symbol_vs;
  83 MetaspaceSharedStats MetaspaceShared::_stats;
  84 bool MetaspaceShared::_has_error_classes;
  85 bool MetaspaceShared::_archive_loading_failed = false;
  86 bool MetaspaceShared::_remapped_readwrite = false;
  87 address MetaspaceShared::_i2i_entry_code_buffers = NULL;
  88 size_t MetaspaceShared::_i2i_entry_code_buffers_size = 0;
  89 void* MetaspaceShared::_shared_metaspace_static_top = NULL;
  90 intx MetaspaceShared::_relocation_delta;
  91 char* MetaspaceShared::_requested_base_address;
  92 bool MetaspaceShared::_use_optimized_module_handling = true;
  93 
  94 // The CDS archive is divided into the following regions:
  95 //     mc  - misc code (the method entry trampolines, c++ vtables)
  96 //     rw  - read-write metadata
  97 //     ro  - read-only metadata and read-only tables
  98 //
  99 //     ca0 - closed archive heap space #0
 100 //     ca1 - closed archive heap space #1 (may be empty)
 101 //     oa0 - open archive heap space #0
 102 //     oa1 - open archive heap space #1 (may be empty)
 103 //
 104 // The mc, rw, and ro regions are linearly allocated, starting from
 105 // SharedBaseAddress, in the order of mc->rw->ro. The size of these 3 regions
 106 // are page-aligned, and there's no gap between any consecutive regions.
 107 //
 108 // These 3 regions are populated in the following steps:
 109 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
 110 //     temporarily allocated outside of the shared regions. Only the method entry
 111 //     trampolines are written into the mc region.
 112 // [2] C++ vtables are copied into the mc region.
 113 // [3] ArchiveCompactor copies RW metadata into the rw region.
 114 // [4] ArchiveCompactor copies RO metadata into the ro region.
 115 // [5] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
 116 //     are copied into the ro region as read-only tables.
 117 //
 118 // The s0/s1 and oa0/oa1 regions are populated inside HeapShared::archive_java_heap_objects.
 119 // Their layout is independent of the other 4 regions.
 120 
 121 char* DumpRegion::expand_top_to(char* newtop) {
 122   assert(is_allocatable(), "must be initialized and not packed");
 123   assert(newtop >= _top, "must not grow backwards");
 124   if (newtop > _end) {
 125     MetaspaceShared::report_out_of_space(_name, newtop - _top);
 126     ShouldNotReachHere();
 127   }
 128 
 129   if (_rs == MetaspaceShared::shared_rs()) {
 130     uintx delta;
 131     if (DynamicDumpSharedSpaces) {
 132       delta = DynamicArchive::object_delta_uintx(newtop);
 133     } else {
 134       delta = MetaspaceShared::object_delta_uintx(newtop);
 135     }
 136     if (delta > MAX_SHARED_DELTA) {
 137       // This is just a sanity check and should not appear in any real world usage. This
 138       // happens only if you allocate more than 2GB of shared objects and would require
 139       // millions of shared classes.
 140       vm_exit_during_initialization("Out of memory in the CDS archive",
 141                                     "Please reduce the number of shared classes.");
 142     }
 143   }
 144 
 145   MetaspaceShared::commit_to(_rs, _vs, newtop);
 146   _top = newtop;
 147   return _top;
 148 }
 149 
 150 char* DumpRegion::allocate(size_t num_bytes, size_t alignment) {
 151   char* p = (char*)align_up(_top, alignment);
 152   char* newtop = p + align_up(num_bytes, alignment);
 153   expand_top_to(newtop);
 154   memset(p, 0, newtop - p);
 155   return p;
 156 }
 157 
 158 void DumpRegion::append_intptr_t(intptr_t n, bool need_to_mark) {
 159   assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
 160   intptr_t *p = (intptr_t*)_top;
 161   char* newtop = _top + sizeof(intptr_t);
 162   expand_top_to(newtop);
 163   *p = n;
 164   if (need_to_mark) {
 165     ArchivePtrMarker::mark_pointer(p);
 166   }
 167 }
 168 
 169 void DumpRegion::print(size_t total_bytes) const {
 170   log_debug(cds)("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,
 171                  _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()),
 172                  p2i(_base + MetaspaceShared::final_delta()));
 173 }
 174 
 175 void DumpRegion::print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
 176   log_error(cds)("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
 177                  _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
 178   if (strcmp(_name, failing_region) == 0) {
 179     log_error(cds)(" required = %d", int(needed_bytes));
 180   }
 181 }
 182 
 183 void DumpRegion::init(ReservedSpace* rs, VirtualSpace* vs) {
 184   _rs = rs;
 185   _vs = vs;
 186   // Start with 0 committed bytes. The memory will be committed as needed by
 187   // MetaspaceShared::commit_to().
 188   if (!_vs->initialize(*_rs, 0)) {
 189     fatal("Unable to allocate memory for shared space");
 190   }
 191   _base = _top = _rs->base();
 192   _end = _rs->end();
 193 }
 194 
 195 void DumpRegion::pack(DumpRegion* next) {
 196   assert(!is_packed(), "sanity");
 197   _end = (char*)align_up(_top, MetaspaceShared::reserved_space_alignment());
 198   _is_packed = true;
 199   if (next != NULL) {
 200     next->_rs = _rs;
 201     next->_vs = _vs;
 202     next->_base = next->_top = this->_end;
 203     next->_end = _rs->end();
 204   }
 205 }
 206 
 207 static DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _symbol_region("symbols");
 208 static size_t _total_closed_archive_region_size = 0, _total_open_archive_region_size = 0;
 209 
 210 void MetaspaceShared::init_shared_dump_space(DumpRegion* first_space) {
 211   first_space->init(&_shared_rs, &_shared_vs);
 212 }
 213 
 214 DumpRegion* MetaspaceShared::misc_code_dump_space() {
 215   return &_mc_region;
 216 }
 217 
 218 DumpRegion* MetaspaceShared::read_write_dump_space() {
 219   return &_rw_region;
 220 }
 221 
 222 DumpRegion* MetaspaceShared::read_only_dump_space() {
 223   return &_ro_region;
 224 }
 225 
 226 void MetaspaceShared::pack_dump_space(DumpRegion* current, DumpRegion* next,
 227                                       ReservedSpace* rs) {
 228   current->pack(next);
 229 }
 230 
 231 char* MetaspaceShared::symbol_space_alloc(size_t num_bytes) {
 232   return _symbol_region.allocate(num_bytes);
 233 }
 234 
 235 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
 236   return _mc_region.allocate(num_bytes);
 237 }
 238 
 239 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
 240   return _ro_region.allocate(num_bytes);
 241 }
 242 
 243 size_t MetaspaceShared::reserved_space_alignment() { return os::vm_allocation_granularity(); }
 244 
 245 static bool shared_base_valid(char* shared_base) {
 246 #ifdef _LP64
 247   return CompressedKlassPointers::is_valid_base((address)shared_base);
 248 #else
 249   return true;
 250 #endif
 251 }
 252 
 253 static bool shared_base_too_high(char* shared_base, size_t cds_total) {
 254   if (SharedBaseAddress != 0 && shared_base < (char*)SharedBaseAddress) {
 255     // SharedBaseAddress is very high (e.g., 0xffffffffffffff00) so
 256     // align_up(SharedBaseAddress, MetaspaceShared::reserved_space_alignment()) has wrapped around.
 257     return true;
 258   }
 259   if (max_uintx - uintx(shared_base) < uintx(cds_total)) {
 260     // The end of the archive will wrap around
 261     return true;
 262   }
 263 
 264   return false;
 265 }
 266 
 267 static char* compute_shared_base(size_t cds_total) {
 268   char* shared_base = (char*)align_up((char*)SharedBaseAddress, MetaspaceShared::reserved_space_alignment());
 269   const char* err = NULL;
 270   if (shared_base_too_high(shared_base, cds_total)) {
 271     err = "too high";
 272   } else if (!shared_base_valid(shared_base)) {
 273     err = "invalid for this platform";
 274   }
 275   if (err) {
 276     log_warning(cds)("SharedBaseAddress (" INTPTR_FORMAT ") is %s. Reverted to " INTPTR_FORMAT,
 277                      p2i((void*)SharedBaseAddress), err,
 278                      p2i((void*)Arguments::default_SharedBaseAddress()));
 279     SharedBaseAddress = Arguments::default_SharedBaseAddress();
 280     shared_base = (char*)align_up((char*)SharedBaseAddress, MetaspaceShared::reserved_space_alignment());
 281   }
 282   assert(!shared_base_too_high(shared_base, cds_total) && shared_base_valid(shared_base), "Sanity");
 283   return shared_base;
 284 }
 285 
 286 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
 287   assert(DumpSharedSpaces, "should be called for dump time only");
 288 
 289   const size_t reserve_alignment = MetaspaceShared::reserved_space_alignment();
 290 
 291 #ifdef _LP64
 292   // On 64-bit VM we reserve a 4G range and, if UseCompressedClassPointers=1,
 293   //  will use that to house both the archives and the ccs. See below for
 294   //  details.
 295   const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
 296   const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
 297 #else
 298   // We don't support archives larger than 256MB on 32-bit due to limited
 299   //  virtual address space.
 300   size_t cds_total = align_down(256*M, reserve_alignment);
 301 #endif
 302 
 303   char* shared_base = compute_shared_base(cds_total);
 304   _requested_base_address = shared_base;
 305 
 306   // Whether to use SharedBaseAddress as attach address.
 307   bool use_requested_base = true;
 308 
 309   if (shared_base == NULL) {
 310     use_requested_base = false;
 311   }
 312 
 313   if (ArchiveRelocationMode == 1) {
 314     log_info(cds)("ArchiveRelocationMode == 1: always allocate class space at an alternative address");
 315     use_requested_base = false;
 316   }
 317 
 318   // First try to reserve the space at the specified SharedBaseAddress.
 319   assert(!_shared_rs.is_reserved(), "must be");
 320   if (use_requested_base) {
 321     _shared_rs = ReservedSpace(cds_total, reserve_alignment,
 322                                false /* large */, (char*)shared_base);
 323     if (_shared_rs.is_reserved()) {
 324       assert(_shared_rs.base() == shared_base, "should match");
 325     } else {
 326       log_info(cds)("dumptime space reservation: failed to map at "
 327                     "SharedBaseAddress " PTR_FORMAT, p2i(shared_base));
 328     }
 329   }
 330   if (!_shared_rs.is_reserved()) {
 331     // Get a reserved space anywhere if attaching at the SharedBaseAddress
 332     //  fails:
 333     if (UseCompressedClassPointers) {
 334       // If we need to reserve class space as well, let the platform handle
 335       //  the reservation.
 336       LP64_ONLY(_shared_rs =
 337                 Metaspace::reserve_address_space_for_compressed_classes(cds_total);)
 338       NOT_LP64(ShouldNotReachHere();)
 339     } else {
 340       // anywhere is fine.
 341       _shared_rs = ReservedSpace(cds_total, reserve_alignment,
 342                                  false /* large */, (char*)NULL);
 343     }
 344   }
 345 
 346   if (!_shared_rs.is_reserved()) {
 347     vm_exit_during_initialization("Unable to reserve memory for shared space",
 348                                   err_msg(SIZE_FORMAT " bytes.", cds_total));
 349   }
 350 
 351 #ifdef _LP64
 352 
 353   if (UseCompressedClassPointers) {
 354 
 355     assert(CompressedKlassPointers::is_valid_base((address)_shared_rs.base()), "Sanity");
 356 
 357     // On 64-bit VM, if UseCompressedClassPointers=1, the compressed class space
 358     //  must be allocated near the cds such as that the compressed Klass pointer
 359     //  encoding can be used to en/decode pointers from both cds and ccs. Since
 360     //  Metaspace cannot do this (it knows nothing about cds), we do it for
 361     //  Metaspace here and pass it the space to use for ccs.
 362     //
 363     // We do this by reserving space for the ccs behind the archives. Note
 364     //  however that ccs follows a different alignment
 365     //  (Metaspace::reserve_alignment), so there may be a gap between ccs and
 366     //  cds.
 367     // We use a similar layout at runtime, see reserve_address_space_for_archives().
 368     //
 369     //                              +-- SharedBaseAddress (default = 0x800000000)
 370     //                              v
 371     // +-..---------+---------+ ... +----+----+----+--------+-----------------+
 372     // |    Heap    | Archive |     | MC | RW | RO | [gap]  |    class space  |
 373     // +-..---------+---------+ ... +----+----+----+--------+-----------------+
 374     // |<--   MaxHeapSize  -->|     |<-- UnscaledClassSpaceMax = 4GB -->|
 375     //
 376     // Note: ccs must follow the archives, and the archives must start at the
 377     //  encoding base. However, the exact placement of ccs does not matter as
 378     //  long as it it resides in the encoding range of CompressedKlassPointers
 379     //  and comes after the archive.
 380     //
 381     // We do this by splitting up the allocated 4G into 3G of archive space,
 382     //  followed by 1G for the ccs:
 383     // + The upper 1 GB is used as the "temporary compressed class space"
 384     //   -- preload_classes() will store Klasses into this space.
 385     // + The lower 3 GB is used for the archive -- when preload_classes()
 386     //   is done, ArchiveCompactor will copy the class metadata into this
 387     //   space, first the RW parts, then the RO parts.
 388 
 389     // Starting address of ccs must be aligned to Metaspace::reserve_alignment()...
 390     size_t class_space_size = align_down(_shared_rs.size() / 4, Metaspace::reserve_alignment());
 391     address class_space_start = (address)align_down(_shared_rs.end() - class_space_size, Metaspace::reserve_alignment());
 392     size_t archive_size = class_space_start - (address)_shared_rs.base();
 393 
 394     ReservedSpace tmp_class_space = _shared_rs.last_part(archive_size);
 395     _shared_rs = _shared_rs.first_part(archive_size);
 396 
 397     // ... as does the size of ccs.
 398     tmp_class_space = tmp_class_space.first_part(class_space_size);
 399     CompressedClassSpaceSize = class_space_size;
 400 
 401     // Let Metaspace initialize ccs
 402     Metaspace::initialize_class_space(tmp_class_space);
 403 
 404     // and set up CompressedKlassPointers encoding.
 405     CompressedKlassPointers::initialize((address)_shared_rs.base(), cds_total);
 406 
 407     log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
 408                   p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
 409 
 410     log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
 411                   CompressedClassSpaceSize, p2i(tmp_class_space.base()));
 412 
 413     assert(_shared_rs.end() == tmp_class_space.base() &&
 414            is_aligned(_shared_rs.base(), MetaspaceShared::reserved_space_alignment()) &&
 415            is_aligned(tmp_class_space.base(), Metaspace::reserve_alignment()) &&
 416            is_aligned(tmp_class_space.size(), Metaspace::reserve_alignment()), "Sanity");
 417   }
 418 
 419 #endif
 420 
 421   init_shared_dump_space(&_mc_region);
 422   SharedBaseAddress = (size_t)_shared_rs.base();
 423   log_info(cds)("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
 424                 _shared_rs.size(), p2i(_shared_rs.base()));
 425 
 426   // We don't want any valid object to be at the very bottom of the archive.
 427   // See ArchivePtrMarker::mark_pointer().
 428   MetaspaceShared::misc_code_space_alloc(16);
 429 
 430   size_t symbol_rs_size = LP64_ONLY(3 * G) NOT_LP64(128 * M);
 431   _symbol_rs = ReservedSpace(symbol_rs_size);
 432   if (!_symbol_rs.is_reserved()) {
 433     vm_exit_during_initialization("Unable to reserve memory for symbols",
 434                                   err_msg(SIZE_FORMAT " bytes.", symbol_rs_size));
 435   }
 436   _symbol_region.init(&_symbol_rs, &_symbol_vs);
 437 }
 438 
 439 // Called by universe_post_init()
 440 void MetaspaceShared::post_initialize(TRAPS) {
 441   if (UseSharedSpaces) {
 442     int size = FileMapInfo::get_number_of_shared_paths();
 443     if (size > 0) {
 444       SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
 445       if (!DynamicDumpSharedSpaces) {
 446         FileMapInfo* info;
 447         if (FileMapInfo::dynamic_info() == NULL) {
 448           info = FileMapInfo::current_info();
 449         } else {
 450           info = FileMapInfo::dynamic_info();
 451         }
 452         ClassLoaderExt::init_paths_start_index(info->app_class_paths_start_index());
 453         ClassLoaderExt::init_app_module_paths_start_index(info->app_module_paths_start_index());
 454       }
 455     }
 456   }
 457 }
 458 
 459 static GrowableArrayCHeap<Handle, mtClassShared>* _extra_interned_strings = NULL;
 460 
 461 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
 462   _extra_interned_strings = new GrowableArrayCHeap<Handle, mtClassShared>(10000);
 463 
 464   HashtableTextDump reader(filename);
 465   reader.check_version("VERSION: 1.0");
 466 
 467   while (reader.remain() > 0) {
 468     int utf8_length;
 469     int prefix_type = reader.scan_prefix(&utf8_length);
 470     ResourceMark rm(THREAD);
 471     if (utf8_length == 0x7fffffff) {
 472       // buf_len will overflown 32-bit value.
 473       vm_exit_during_initialization(err_msg("string length too large: %d", utf8_length));
 474     }
 475     int buf_len = utf8_length+1;
 476     char* utf8_buffer = NEW_RESOURCE_ARRAY(char, buf_len);
 477     reader.get_utf8(utf8_buffer, utf8_length);
 478     utf8_buffer[utf8_length] = '\0';
 479 
 480     if (prefix_type == HashtableTextDump::SymbolPrefix) {
 481       SymbolTable::new_permanent_symbol(utf8_buffer);
 482     } else{
 483       assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
 484       oop s = StringTable::intern(utf8_buffer, THREAD);
 485 
 486       if (HAS_PENDING_EXCEPTION) {
 487         log_warning(cds, heap)("[line %d] extra interned string allocation failed; size too large: %d",
 488                                reader.last_line_no(), utf8_length);
 489         CLEAR_PENDING_EXCEPTION;
 490       } else {
 491 #if INCLUDE_G1GC
 492         if (UseG1GC) {
 493           typeArrayOop body = java_lang_String::value(s);
 494           const HeapRegion* hr = G1CollectedHeap::heap()->heap_region_containing(body);
 495           if (hr->is_humongous()) {
 496             // Don't keep it alive, so it will be GC'ed before we dump the strings, in order
 497             // to maximize free heap space and minimize fragmentation.
 498             log_warning(cds, heap)("[line %d] extra interned string ignored; size too large: %d",
 499                                 reader.last_line_no(), utf8_length);
 500             continue;
 501           }
 502         }
 503 #endif
 504         // Interned strings are GC'ed if there are no references to it, so let's
 505         // add a reference to keep this string alive.
 506         assert(s != NULL, "must succeed");
 507         Handle h(THREAD, s);
 508         _extra_interned_strings->append(h);
 509       }
 510     }
 511   }
 512 }
 513 
 514 void MetaspaceShared::commit_to(ReservedSpace* rs, VirtualSpace* vs, char* newtop) {
 515   Arguments::assert_is_dumping_archive();
 516   char* base = rs->base();
 517   size_t need_committed_size = newtop - base;
 518   size_t has_committed_size = vs->committed_size();
 519   if (need_committed_size < has_committed_size) {
 520     return;
 521   }
 522 
 523   size_t min_bytes = need_committed_size - has_committed_size;
 524   size_t preferred_bytes = 1 * M;
 525   size_t uncommitted = vs->reserved_size() - has_committed_size;
 526 
 527   size_t commit =MAX2(min_bytes, preferred_bytes);
 528   commit = MIN2(commit, uncommitted);
 529   assert(commit <= uncommitted, "sanity");
 530 
 531   bool result = vs->expand_by(commit, false);
 532   if (rs == &_shared_rs) {
 533     ArchivePtrMarker::expand_ptr_end((address*)vs->high());
 534   }
 535 
 536   if (!result) {
 537     vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
 538                                           need_committed_size));
 539   }
 540 
 541   assert(rs == &_shared_rs || rs == &_symbol_rs, "must be");
 542   const char* which = (rs == &_shared_rs) ? "shared" : "symbol";
 543   log_debug(cds)("Expanding %s spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9)  " bytes ending at %p]",
 544                  which, commit, vs->actual_committed_size(), vs->high());
 545 }
 546 
 547 void MetaspaceShared::initialize_ptr_marker(CHeapBitMap* ptrmap) {
 548   ArchivePtrMarker::initialize(ptrmap, (address*)_shared_vs.low(), (address*)_shared_vs.high());
 549 }
 550 
 551 // Read/write a data stream for restoring/preserving metadata pointers and
 552 // miscellaneous data from/to the shared archive file.
 553 
 554 void MetaspaceShared::serialize(SerializeClosure* soc) {
 555   int tag = 0;
 556   soc->do_tag(--tag);
 557 
 558   // Verify the sizes of various metadata in the system.
 559   soc->do_tag(sizeof(Method));
 560   soc->do_tag(sizeof(ConstMethod));
 561   soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
 562   soc->do_tag(sizeof(ConstantPool));
 563   soc->do_tag(sizeof(ConstantPoolCache));
 564   soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
 565   soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
 566   soc->do_tag(sizeof(Symbol));
 567 
 568   // Dump/restore miscellaneous metadata.
 569   JavaClasses::serialize_offsets(soc);
 570   Universe::serialize(soc);
 571   soc->do_tag(--tag);
 572 
 573   // Dump/restore references to commonly used names and signatures.
 574   vmSymbols::serialize(soc);
 575   soc->do_tag(--tag);
 576 
 577   // Dump/restore the symbol/string/subgraph_info tables
 578   SymbolTable::serialize_shared_table_header(soc);
 579   StringTable::serialize_shared_table_header(soc);
 580   HeapShared::serialize_subgraph_info_table_header(soc);
 581   SystemDictionaryShared::serialize_dictionary_headers(soc);
 582 
 583   InstanceMirrorKlass::serialize_offsets(soc);
 584 
 585   // Dump/restore well known classes (pointers)
 586   SystemDictionaryShared::serialize_well_known_klasses(soc);
 587   soc->do_tag(--tag);
 588 
 589   serialize_cloned_cpp_vtptrs(soc);
 590   soc->do_tag(--tag);
 591 
 592   soc->do_tag(666);
 593 }
 594 
 595 address MetaspaceShared::i2i_entry_code_buffers(size_t total_size) {
 596   if (DumpSharedSpaces) {
 597     if (_i2i_entry_code_buffers == NULL) {
 598       _i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
 599       _i2i_entry_code_buffers_size = total_size;
 600     }
 601   } else if (UseSharedSpaces) {
 602     assert(_i2i_entry_code_buffers != NULL, "must already been initialized");
 603   } else {
 604     return NULL;
 605   }
 606 
 607   assert(_i2i_entry_code_buffers_size == total_size, "must not change");
 608   return _i2i_entry_code_buffers;
 609 }
 610 
 611 uintx MetaspaceShared::object_delta_uintx(void* obj) {
 612   Arguments::assert_is_dumping_archive();
 613   if (DumpSharedSpaces) {
 614     assert(shared_rs()->contains(obj), "must be");
 615   } else {
 616     assert(is_in_shared_metaspace(obj) || DynamicArchive::is_in_target_space(obj), "must be");
 617   }
 618   address base_address = address(SharedBaseAddress);
 619   uintx deltax = address(obj) - base_address;
 620   return deltax;
 621 }
 622 
 623 // Global object for holding classes that have been loaded.  Since this
 624 // is run at a safepoint just before exit, this is the entire set of classes.
 625 static GrowableArray<Klass*>* _global_klass_objects;
 626 
 627 static int global_klass_compare(Klass** a, Klass **b) {
 628   return a[0]->name()->fast_compare(b[0]->name());
 629 }
 630 
 631 GrowableArray<Klass*>* MetaspaceShared::collected_klasses() {
 632   return _global_klass_objects;
 633 }
 634 
 635 static void collect_array_classes(Klass* k) {
 636   _global_klass_objects->append_if_missing(k);
 637   if (k->is_array_klass()) {
 638     // Add in the array classes too
 639     ArrayKlass* ak = ArrayKlass::cast(k);
 640     Klass* h = ak->higher_dimension();
 641     if (h != NULL) {
 642       h->array_klasses_do(collect_array_classes);
 643     }
 644   }
 645 }
 646 
 647 class CollectClassesClosure : public KlassClosure {
 648   void do_klass(Klass* k) {
 649     if (k->is_instance_klass() &&
 650         SystemDictionaryShared::is_excluded_class(InstanceKlass::cast(k))) {
 651       // Don't add to the _global_klass_objects
 652     } else {
 653       _global_klass_objects->append_if_missing(k);
 654     }
 655     if (k->is_array_klass()) {
 656       // Add in the array classes too
 657       ArrayKlass* ak = ArrayKlass::cast(k);
 658       Klass* h = ak->higher_dimension();
 659       if (h != NULL) {
 660         h->array_klasses_do(collect_array_classes);
 661       }
 662     }
 663   }
 664 };
 665 
 666 // Global object for holding symbols that created during class loading. See SymbolTable::new_symbol
 667 static GrowableArray<Symbol*>* _global_symbol_objects = NULL;
 668 
 669 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
 670   if (a[0] < b[0]) {
 671     return -1;
 672   } else if (a[0] == b[0]) {
 673     ResourceMark rm;
 674     log_warning(cds)("Duplicated symbol %s unexpected", (*a)->as_C_string());
 675     return 0;
 676   } else {
 677     return 1;
 678   }
 679 }
 680 
 681 void MetaspaceShared::add_symbol(Symbol* sym) {
 682   MutexLocker ml(CDSAddSymbol_lock, Mutex::_no_safepoint_check_flag);
 683   if (_global_symbol_objects == NULL) {
 684     _global_symbol_objects = new (ResourceObj::C_HEAP, mtSymbol) GrowableArray<Symbol*>(2048, mtSymbol);
 685   }
 686   _global_symbol_objects->append(sym);
 687 }
 688 
 689 GrowableArray<Symbol*>* MetaspaceShared::collected_symbols() {
 690   return _global_symbol_objects;
 691 }
 692 
 693 static void remove_unshareable_in_classes() {
 694   for (int i = 0; i < _global_klass_objects->length(); i++) {
 695     Klass* k = _global_klass_objects->at(i);
 696     if (!k->is_objArray_klass()) {
 697       // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
 698       // on their array classes.
 699       assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
 700       k->remove_unshareable_info();
 701     }
 702   }
 703 }
 704 
 705 static void remove_java_mirror_in_classes() {
 706   for (int i = 0; i < _global_klass_objects->length(); i++) {
 707     Klass* k = _global_klass_objects->at(i);
 708     if (!k->is_objArray_klass()) {
 709       // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
 710       // on their array classes.
 711       assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
 712       k->remove_java_mirror();
 713     }
 714   }
 715 }
 716 
 717 static void clear_basic_type_mirrors() {
 718   assert(!HeapShared::is_heap_object_archiving_allowed(), "Sanity");
 719   Universe::set_int_mirror(NULL);
 720   Universe::set_float_mirror(NULL);
 721   Universe::set_double_mirror(NULL);
 722   Universe::set_byte_mirror(NULL);
 723   Universe::set_bool_mirror(NULL);
 724   Universe::set_char_mirror(NULL);
 725   Universe::set_long_mirror(NULL);
 726   Universe::set_short_mirror(NULL);
 727   Universe::set_void_mirror(NULL);
 728 }
 729 
 730 static void rewrite_nofast_bytecode(const methodHandle& method) {
 731   BytecodeStream bcs(method);
 732   while (!bcs.is_last_bytecode()) {
 733     Bytecodes::Code opcode = bcs.next();
 734     switch (opcode) {
 735     case Bytecodes::_getfield:      *bcs.bcp() = Bytecodes::_nofast_getfield;      break;
 736     case Bytecodes::_putfield:      *bcs.bcp() = Bytecodes::_nofast_putfield;      break;
 737     case Bytecodes::_aload_0:       *bcs.bcp() = Bytecodes::_nofast_aload_0;       break;
 738     case Bytecodes::_iload: {
 739       if (!bcs.is_wide()) {
 740         *bcs.bcp() = Bytecodes::_nofast_iload;
 741       }
 742       break;
 743     }
 744     default: break;
 745     }
 746   }
 747 }
 748 
 749 // Walk all methods in the class list to ensure that they won't be modified at
 750 // run time. This includes:
 751 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
 752 //     at run time by RewriteBytecodes/RewriteFrequentPairs
 753 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
 754 static void rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread) {
 755   for (int i = 0; i < _global_klass_objects->length(); i++) {
 756     Klass* k = _global_klass_objects->at(i);
 757     if (k->is_instance_klass()) {
 758       InstanceKlass* ik = InstanceKlass::cast(k);
 759       MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(thread, ik);
 760     }
 761   }
 762 }
 763 
 764 void MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread, InstanceKlass* ik) {
 765   for (int i = 0; i < ik->methods()->length(); i++) {
 766     methodHandle m(thread, ik->methods()->at(i));
 767     rewrite_nofast_bytecode(m);
 768     Fingerprinter fp(m);
 769     // The side effect of this call sets method's fingerprint field.
 770     fp.fingerprint();
 771   }
 772 }
 773 
 774 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
 775 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
 776 //
 777 // Addresses of the vtables and the methods may be different across JVM runs,
 778 // if libjvm.so is dynamically loaded at a different base address.
 779 //
 780 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
 781 //
 782 // + at dump time:  we redirect the _vptr to point to our own vtables inside
 783 //                  the CDS image
 784 // + at run time:   we clone the actual contents of the vtables from libjvm.so
 785 //                  into our own tables.
 786 
 787 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
 788 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
 789   f(ConstantPool) \
 790   f(InstanceKlass) \
 791   f(InstanceClassLoaderKlass) \
 792   f(InstanceMirrorKlass) \
 793   f(InstanceRefKlass) \
 794   f(Method) \
 795   f(ObjArrayKlass) \
 796   f(TypeArrayKlass)
 797 
 798 class CppVtableInfo {
 799   intptr_t _vtable_size;
 800   intptr_t _cloned_vtable[1];
 801 public:
 802   static int num_slots(int vtable_size) {
 803     return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
 804   }
 805   int vtable_size()           { return int(uintx(_vtable_size)); }
 806   void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
 807   intptr_t* cloned_vtable()   { return &_cloned_vtable[0]; }
 808   void zero()                 { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
 809   // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
 810   static size_t byte_size(int vtable_size) {
 811     CppVtableInfo i;
 812     return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
 813   }
 814 };
 815 
 816 static inline intptr_t* vtable_of(Metadata* m) {
 817   return *((intptr_t**)m);
 818 }
 819 
 820 template <class T> class CppVtableCloner : public T {
 821   static CppVtableInfo* _info;
 822 
 823   static int get_vtable_length(const char* name);
 824 
 825 public:
 826   // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
 827   static intptr_t* allocate(const char* name);
 828 
 829   // Clone the vtable to ...
 830   static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
 831 
 832   static void zero_vtable_clone() {
 833     assert(DumpSharedSpaces, "dump-time only");
 834     _info->zero();
 835   }
 836 
 837   static bool is_valid_shared_object(const T* obj) {
 838     intptr_t* vptr = *(intptr_t**)obj;
 839     return vptr == _info->cloned_vtable();
 840   }
 841 
 842   static void init_orig_cpp_vtptr(int kind);
 843 };
 844 
 845 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
 846 
 847 template <class T>
 848 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
 849   assert(is_aligned(_mc_region.top(), sizeof(intptr_t)), "bad alignment");
 850   int n = get_vtable_length(name);
 851   _info = (CppVtableInfo*)_mc_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
 852   _info->set_vtable_size(n);
 853 
 854   intptr_t* p = clone_vtable(name, _info);
 855   assert((char*)p == _mc_region.top(), "must be");
 856 
 857   return _info->cloned_vtable();
 858 }
 859 
 860 template <class T>
 861 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
 862   if (!DumpSharedSpaces) {
 863     assert(_info == 0, "_info is initialized only at dump time");
 864     _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
 865   }
 866   T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
 867   int n = info->vtable_size();
 868   intptr_t* srcvtable = vtable_of(&tmp);
 869   intptr_t* dstvtable = info->cloned_vtable();
 870 
 871   // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
 872   // safe to do memcpy.
 873   log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
 874   memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
 875   return dstvtable + n;
 876 }
 877 
 878 // To determine the size of the vtable for each type, we use the following
 879 // trick by declaring 2 subclasses:
 880 //
 881 //   class CppVtableTesterA: public InstanceKlass {virtual int   last_virtual_method() {return 1;}    };
 882 //   class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
 883 //
 884 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
 885 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
 886 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
 887 // - Their last entry is different.
 888 //
 889 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
 890 // and find the first entry that's different.
 891 //
 892 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
 893 // esoteric compilers.
 894 
 895 template <class T> class CppVtableTesterB: public T {
 896 public:
 897   virtual int last_virtual_method() {return 1;}
 898 };
 899 
 900 template <class T> class CppVtableTesterA : public T {
 901 public:
 902   virtual void* last_virtual_method() {
 903     // Make this different than CppVtableTesterB::last_virtual_method so the C++
 904     // compiler/linker won't alias the two functions.
 905     return NULL;
 906   }
 907 };
 908 
 909 template <class T>
 910 int CppVtableCloner<T>::get_vtable_length(const char* name) {
 911   CppVtableTesterA<T> a;
 912   CppVtableTesterB<T> b;
 913 
 914   intptr_t* avtable = vtable_of(&a);
 915   intptr_t* bvtable = vtable_of(&b);
 916 
 917   // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
 918   int vtable_len = 1;
 919   for (; ; vtable_len++) {
 920     if (avtable[vtable_len] != bvtable[vtable_len]) {
 921       break;
 922     }
 923   }
 924   log_debug(cds, vtables)("Found   %3d vtable entries for %s", vtable_len, name);
 925 
 926   return vtable_len;
 927 }
 928 
 929 #define ALLOC_CPP_VTABLE_CLONE(c) \
 930   _cloned_cpp_vtptrs[c##_Kind] = CppVtableCloner<c>::allocate(#c); \
 931   ArchivePtrMarker::mark_pointer(&_cloned_cpp_vtptrs[c##_Kind]);
 932 
 933 #define CLONE_CPP_VTABLE(c) \
 934   p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
 935 
 936 #define ZERO_CPP_VTABLE(c) \
 937  CppVtableCloner<c>::zero_vtable_clone();
 938 
 939 #define INIT_ORIG_CPP_VTPTRS(c) \
 940   CppVtableCloner<c>::init_orig_cpp_vtptr(c##_Kind);
 941 
 942 #define DECLARE_CLONED_VTABLE_KIND(c) c ## _Kind,
 943 
 944 enum ClonedVtableKind {
 945   // E.g., ConstantPool_Kind == 0, InstanceKlass_Kind == 1, etc.
 946   CPP_VTABLE_PATCH_TYPES_DO(DECLARE_CLONED_VTABLE_KIND)
 947   _num_cloned_vtable_kinds
 948 };
 949 
 950 // This is a map of all the original vtptrs. E.g., for
 951 //     ConstantPool *cp = new (...) ConstantPool(...) ; // a dynamically allocated constant pool
 952 // the following holds true:
 953 //     _orig_cpp_vtptrs[ConstantPool_Kind] ==  ((intptr_t**)cp)[0]
 954 static intptr_t* _orig_cpp_vtptrs[_num_cloned_vtable_kinds];
 955 static bool _orig_cpp_vtptrs_inited = false;
 956 
 957 template <class T>
 958 void CppVtableCloner<T>::init_orig_cpp_vtptr(int kind) {
 959   assert(kind < _num_cloned_vtable_kinds, "sanity");
 960   T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
 961   intptr_t* srcvtable = vtable_of(&tmp);
 962   _orig_cpp_vtptrs[kind] = srcvtable;
 963 }
 964 
 965 // This is the index of all the cloned vtables. E.g., for
 966 //     ConstantPool* cp = ....; // an archived constant pool
 967 //     InstanceKlass* ik = ....;// an archived class
 968 // the following holds true:
 969 //     _cloned_cpp_vtptrs[ConstantPool_Kind]  == ((intptr_t**)cp)[0]
 970 //     _cloned_cpp_vtptrs[InstanceKlass_Kind] == ((intptr_t**)ik)[0]
 971 static intptr_t** _cloned_cpp_vtptrs = NULL;
 972 
 973 void MetaspaceShared::allocate_cloned_cpp_vtptrs() {
 974   assert(DumpSharedSpaces, "must");
 975   size_t vtptrs_bytes = _num_cloned_vtable_kinds * sizeof(intptr_t*);
 976   _cloned_cpp_vtptrs = (intptr_t**)_mc_region.allocate(vtptrs_bytes, sizeof(intptr_t*));
 977 }
 978 
 979 void MetaspaceShared::serialize_cloned_cpp_vtptrs(SerializeClosure* soc) {
 980   soc->do_ptr((void**)&_cloned_cpp_vtptrs);
 981 }
 982 
 983 intptr_t* MetaspaceShared::get_archived_cpp_vtable(MetaspaceObj::Type msotype, address obj) {
 984   if (!_orig_cpp_vtptrs_inited) {
 985     CPP_VTABLE_PATCH_TYPES_DO(INIT_ORIG_CPP_VTPTRS);
 986     _orig_cpp_vtptrs_inited = true;
 987   }
 988 
 989   Arguments::assert_is_dumping_archive();
 990   int kind = -1;
 991   switch (msotype) {
 992   case MetaspaceObj::SymbolType:
 993   case MetaspaceObj::TypeArrayU1Type:
 994   case MetaspaceObj::TypeArrayU2Type:
 995   case MetaspaceObj::TypeArrayU4Type:
 996   case MetaspaceObj::TypeArrayU8Type:
 997   case MetaspaceObj::TypeArrayOtherType:
 998   case MetaspaceObj::ConstMethodType:
 999   case MetaspaceObj::ConstantPoolCacheType:
1000   case MetaspaceObj::AnnotationsType:
1001   case MetaspaceObj::MethodCountersType:
1002   case MetaspaceObj::RecordComponentType:
1003     // These have no vtables.
1004     break;
1005   case MetaspaceObj::MethodDataType:
1006     // We don't archive MethodData <-- should have been removed in removed_unsharable_info
1007     ShouldNotReachHere();
1008     break;
1009   default:
1010     for (kind = 0; kind < _num_cloned_vtable_kinds; kind ++) {
1011       if (vtable_of((Metadata*)obj) == _orig_cpp_vtptrs[kind]) {
1012         break;
1013       }
1014     }
1015     if (kind >= _num_cloned_vtable_kinds) {
1016       fatal("Cannot find C++ vtable for " INTPTR_FORMAT " -- you probably added"
1017             " a new subtype of Klass or MetaData without updating CPP_VTABLE_PATCH_TYPES_DO",
1018             p2i(obj));
1019     }
1020   }
1021 
1022   if (kind >= 0) {
1023     assert(kind < _num_cloned_vtable_kinds, "must be");
1024     return _cloned_cpp_vtptrs[kind];
1025   } else {
1026     return NULL;
1027   }
1028 }
1029 
1030 // This can be called at both dump time and run time:
1031 // - clone the contents of the c++ vtables into the space
1032 //   allocated by allocate_cpp_vtable_clones()
1033 void MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
1034   assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
1035   CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
1036 }
1037 
1038 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
1039   assert(DumpSharedSpaces, "dump-time only");
1040   CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
1041 }
1042 
1043 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
1044 char* MetaspaceShared::allocate_cpp_vtable_clones() {
1045   char* cloned_vtables = _mc_region.top(); // This is the beginning of all the cloned vtables
1046 
1047   assert(DumpSharedSpaces, "dump-time only");
1048   // Layout (each slot is a intptr_t):
1049   //   [number of slots in the first vtable = n1]
1050   //   [ <n1> slots for the first vtable]
1051   //   [number of slots in the first second = n2]
1052   //   [ <n2> slots for the second vtable]
1053   //   ...
1054   // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
1055   CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
1056 
1057   return cloned_vtables;
1058 }
1059 
1060 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
1061   assert(is_in_shared_metaspace(m), "must be");
1062   return CppVtableCloner<Method>::is_valid_shared_object(m);
1063 }
1064 
1065 void WriteClosure::do_oop(oop* o) {
1066   if (*o == NULL) {
1067     _dump_region->append_intptr_t(0);
1068   } else {
1069     assert(HeapShared::is_heap_object_archiving_allowed(),
1070            "Archiving heap object is not allowed");
1071     _dump_region->append_intptr_t(
1072       (intptr_t)CompressedOops::encode_not_null(*o));
1073   }
1074 }
1075 
1076 void WriteClosure::do_region(u_char* start, size_t size) {
1077   assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1078   assert(size % sizeof(intptr_t) == 0, "bad size");
1079   do_tag((int)size);
1080   while (size > 0) {
1081     _dump_region->append_intptr_t(*(intptr_t*)start, true);
1082     start += sizeof(intptr_t);
1083     size -= sizeof(intptr_t);
1084   }
1085 }
1086 
1087 // This is for dumping detailed statistics for the allocations
1088 // in the shared spaces.
1089 class DumpAllocStats : public ResourceObj {
1090 public:
1091 
1092   // Here's poor man's enum inheritance
1093 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
1094   METASPACE_OBJ_TYPES_DO(f) \
1095   f(SymbolHashentry) \
1096   f(SymbolBucket) \
1097   f(StringHashentry) \
1098   f(StringBucket) \
1099   f(Other)
1100 
1101   enum Type {
1102     // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
1103     SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
1104     _number_of_types
1105   };
1106 
1107   static const char * type_name(Type type) {
1108     switch(type) {
1109     SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
1110     default:
1111       ShouldNotReachHere();
1112       return NULL;
1113     }
1114   }
1115 
1116 public:
1117   enum { RO = 0, RW = 1 };
1118 
1119   int _counts[2][_number_of_types];
1120   int _bytes [2][_number_of_types];
1121 
1122   DumpAllocStats() {
1123     memset(_counts, 0, sizeof(_counts));
1124     memset(_bytes,  0, sizeof(_bytes));
1125   };
1126 
1127   void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
1128     assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
1129     int which = (read_only) ? RO : RW;
1130     _counts[which][type] ++;
1131     _bytes [which][type] += byte_size;
1132   }
1133 
1134   void record_other_type(int byte_size, bool read_only) {
1135     int which = (read_only) ? RO : RW;
1136     _bytes [which][OtherType] += byte_size;
1137   }
1138   void print_stats(int ro_all, int rw_all, int mc_all);
1139 };
1140 
1141 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all) {
1142   // Calculate size of data that was not allocated by Metaspace::allocate()
1143   MetaspaceSharedStats *stats = MetaspaceShared::stats();
1144 
1145   // symbols
1146   _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
1147   _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
1148 
1149   _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
1150   _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
1151 
1152   // strings
1153   _counts[RO][StringHashentryType] = stats->string.hashentry_count;
1154   _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
1155 
1156   _counts[RO][StringBucketType] = stats->string.bucket_count;
1157   _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
1158 
1159   // TODO: count things like dictionary, vtable, etc
1160   _bytes[RW][OtherType] += mc_all;
1161   rw_all += mc_all; // mc is mapped Read/Write
1162 
1163   // prevent divide-by-zero
1164   if (ro_all < 1) {
1165     ro_all = 1;
1166   }
1167   if (rw_all < 1) {
1168     rw_all = 1;
1169   }
1170 
1171   int all_ro_count = 0;
1172   int all_ro_bytes = 0;
1173   int all_rw_count = 0;
1174   int all_rw_bytes = 0;
1175 
1176 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
1177 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
1178   const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
1179   const char *hdr = "                        ro_cnt   ro_bytes     % |   rw_cnt   rw_bytes     % |  all_cnt  all_bytes     %";
1180 
1181   LogMessage(cds) msg;
1182 
1183   msg.debug("Detailed metadata info (excluding st regions; rw stats include mc regions):");
1184   msg.debug("%s", hdr);
1185   msg.debug("%s", sep);
1186   for (int type = 0; type < int(_number_of_types); type ++) {
1187     const char *name = type_name((Type)type);
1188     int ro_count = _counts[RO][type];
1189     int ro_bytes = _bytes [RO][type];
1190     int rw_count = _counts[RW][type];
1191     int rw_bytes = _bytes [RW][type];
1192     int count = ro_count + rw_count;
1193     int bytes = ro_bytes + rw_bytes;
1194 
1195     double ro_perc = percent_of(ro_bytes, ro_all);
1196     double rw_perc = percent_of(rw_bytes, rw_all);
1197     double perc    = percent_of(bytes, ro_all + rw_all);
1198 
1199     msg.debug(fmt_stats, name,
1200                          ro_count, ro_bytes, ro_perc,
1201                          rw_count, rw_bytes, rw_perc,
1202                          count, bytes, perc);
1203 
1204     all_ro_count += ro_count;
1205     all_ro_bytes += ro_bytes;
1206     all_rw_count += rw_count;
1207     all_rw_bytes += rw_bytes;
1208   }
1209 
1210   int all_count = all_ro_count + all_rw_count;
1211   int all_bytes = all_ro_bytes + all_rw_bytes;
1212 
1213   double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1214   double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1215   double all_perc    = percent_of(all_bytes, ro_all + rw_all);
1216 
1217   msg.debug("%s", sep);
1218   msg.debug(fmt_stats, "Total",
1219                        all_ro_count, all_ro_bytes, all_ro_perc,
1220                        all_rw_count, all_rw_bytes, all_rw_perc,
1221                        all_count, all_bytes, all_perc);
1222 
1223   assert(all_ro_bytes == ro_all, "everything should have been counted");
1224   assert(all_rw_bytes == rw_all, "everything should have been counted");
1225 
1226 #undef fmt_stats
1227 }
1228 
1229 // Populate the shared space.
1230 
1231 class VM_PopulateDumpSharedSpace: public VM_Operation {
1232 private:
1233   GrowableArray<MemRegion> *_closed_archive_heap_regions;
1234   GrowableArray<MemRegion> *_open_archive_heap_regions;
1235 
1236   GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1237   GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1238 
1239   void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1240   void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1241   void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1242                                  GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1243   void dump_symbols();
1244   char* dump_read_only_tables();
1245   void print_class_stats();
1246   void print_region_stats(FileMapInfo* map_info);
1247   void print_bitmap_region_stats(size_t size, size_t total_size);
1248   void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1249                                const char *name, size_t total_size);
1250   void relocate_to_requested_base_address(CHeapBitMap* ptrmap);
1251 
1252 public:
1253 
1254   VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1255   void doit();   // outline because gdb sucks
1256   bool allow_nested_vm_operations() const { return true; }
1257 }; // class VM_PopulateDumpSharedSpace
1258 
1259 // ArchiveCompactor --
1260 //
1261 // This class is the central piece of shared archive compaction -- all metaspace data are
1262 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1263 // metaspace data into their final location in the shared regions.
1264 
1265 class ArchiveCompactor : AllStatic {
1266   static const int INITIAL_TABLE_SIZE = 8087;
1267   static const int MAX_TABLE_SIZE     = 1000000;
1268 
1269   static DumpAllocStats* _alloc_stats;
1270 
1271   typedef KVHashtable<address, address, mtInternal> RelocationTable;
1272   static RelocationTable* _new_loc_table;
1273 
1274 public:
1275   static void initialize() {
1276     _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1277     _new_loc_table = new RelocationTable(INITIAL_TABLE_SIZE);
1278   }
1279   static DumpAllocStats* alloc_stats() {
1280     return _alloc_stats;
1281   }
1282 
1283   // Use this when you allocate space with MetaspaceShare::read_only_space_alloc()
1284   // outside of ArchiveCompactor::allocate(). These are usually for misc tables
1285   // that are allocated in the RO space.
1286   class OtherROAllocMark {
1287     char* _oldtop;
1288   public:
1289     OtherROAllocMark() {
1290       _oldtop = _ro_region.top();
1291     }
1292     ~OtherROAllocMark() {
1293       char* newtop = _ro_region.top();
1294       ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - _oldtop), true);
1295     }
1296   };
1297 
1298   static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1299     address obj = ref->obj();
1300     int bytes = ref->size() * BytesPerWord;
1301     char* p;
1302     size_t alignment = BytesPerWord;
1303     char* oldtop;
1304     char* newtop;
1305 
1306     if (read_only) {
1307       oldtop = _ro_region.top();
1308       p = _ro_region.allocate(bytes, alignment);
1309       newtop = _ro_region.top();
1310     } else {
1311       oldtop = _rw_region.top();
1312       if (ref->msotype() == MetaspaceObj::ClassType) {
1313         // Save a pointer immediate in front of an InstanceKlass, so
1314         // we can do a quick lookup from InstanceKlass* -> RunTimeSharedClassInfo*
1315         // without building another hashtable. See RunTimeSharedClassInfo::get_for()
1316         // in systemDictionaryShared.cpp.
1317         Klass* klass = (Klass*)obj;
1318         if (klass->is_instance_klass()) {
1319           SystemDictionaryShared::validate_before_archiving(InstanceKlass::cast(klass));
1320           _rw_region.allocate(sizeof(address), BytesPerWord);
1321         }
1322       }
1323       p = _rw_region.allocate(bytes, alignment);
1324       newtop = _rw_region.top();
1325     }
1326     memcpy(p, obj, bytes);
1327 
1328     intptr_t* archived_vtable = MetaspaceShared::get_archived_cpp_vtable(ref->msotype(), (address)p);
1329     if (archived_vtable != NULL) {
1330       *(address*)p = (address)archived_vtable;
1331       ArchivePtrMarker::mark_pointer((address*)p);
1332     }
1333 
1334     assert(_new_loc_table->lookup(obj) == NULL, "each object can be relocated at most once");
1335     _new_loc_table->add(obj, (address)p);
1336     log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1337     if (_new_loc_table->maybe_grow(MAX_TABLE_SIZE)) {
1338       log_info(cds, hashtables)("Expanded _new_loc_table to %d", _new_loc_table->table_size());
1339     }
1340     _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1341   }
1342 
1343   static address get_new_loc(MetaspaceClosure::Ref* ref) {
1344     address* pp = _new_loc_table->lookup(ref->obj());
1345     assert(pp != NULL, "must be");
1346     return *pp;
1347   }
1348 
1349 private:
1350   // Makes a shallow copy of visited MetaspaceObj's
1351   class ShallowCopier: public UniqueMetaspaceClosure {
1352     bool _read_only;
1353   public:
1354     ShallowCopier(bool read_only) : _read_only(read_only) {}
1355 
1356     virtual bool do_unique_ref(Ref* ref, bool read_only) {
1357       if (read_only == _read_only) {
1358         allocate(ref, read_only);
1359       }
1360       return true; // recurse into ref.obj()
1361     }
1362   };
1363 
1364   // Relocate embedded pointers within a MetaspaceObj's shallow copy
1365   class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1366   public:
1367     virtual bool do_unique_ref(Ref* ref, bool read_only) {
1368       address new_loc = get_new_loc(ref);
1369       RefRelocator refer;
1370       ref->metaspace_pointers_do_at(&refer, new_loc);
1371       return true; // recurse into ref.obj()
1372     }
1373     virtual void push_special(SpecialRef type, Ref* ref, intptr_t* p) {
1374       assert(type == _method_entry_ref, "only special type allowed for now");
1375       address obj = ref->obj();
1376       address new_obj = get_new_loc(ref);
1377       size_t offset = pointer_delta(p, obj,  sizeof(u1));
1378       intptr_t* new_p = (intptr_t*)(new_obj + offset);
1379       assert(*p == *new_p, "must be a copy");
1380       ArchivePtrMarker::mark_pointer((address*)new_p);
1381     }
1382   };
1383 
1384   // Relocate a reference to point to its shallow copy
1385   class RefRelocator: public MetaspaceClosure {
1386   public:
1387     virtual bool do_ref(Ref* ref, bool read_only) {
1388       if (ref->not_null()) {
1389         ref->update(get_new_loc(ref));
1390         ArchivePtrMarker::mark_pointer(ref->addr());
1391       }
1392       return false; // Do not recurse.
1393     }
1394   };
1395 
1396 #ifdef ASSERT
1397   class IsRefInArchiveChecker: public MetaspaceClosure {
1398   public:
1399     virtual bool do_ref(Ref* ref, bool read_only) {
1400       if (ref->not_null()) {
1401         char* obj = (char*)ref->obj();
1402         assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1403                "must be relocated to point to CDS archive");
1404       }
1405       return false; // Do not recurse.
1406     }
1407   };
1408 #endif
1409 
1410 public:
1411   static void copy_and_compact() {
1412     ResourceMark rm;
1413 
1414     log_info(cds)("Scanning all metaspace objects ... ");
1415     {
1416       // allocate and shallow-copy RW objects, immediately following the MC region
1417       log_info(cds)("Allocating RW objects ... ");
1418       _mc_region.pack(&_rw_region);
1419 
1420       ResourceMark rm;
1421       ShallowCopier rw_copier(false);
1422       iterate_roots(&rw_copier);
1423     }
1424     {
1425       // allocate and shallow-copy of RO object, immediately following the RW region
1426       log_info(cds)("Allocating RO objects ... ");
1427       _rw_region.pack(&_ro_region);
1428 
1429       ResourceMark rm;
1430       ShallowCopier ro_copier(true);
1431       iterate_roots(&ro_copier);
1432     }
1433     {
1434       log_info(cds)("Relocating embedded pointers ... ");
1435       ResourceMark rm;
1436       ShallowCopyEmbeddedRefRelocator emb_reloc;
1437       iterate_roots(&emb_reloc);
1438     }
1439     {
1440       log_info(cds)("Relocating external roots ... ");
1441       ResourceMark rm;
1442       RefRelocator ext_reloc;
1443       iterate_roots(&ext_reloc);
1444     }
1445     {
1446       log_info(cds)("Fixing symbol identity hash ... ");
1447       os::init_random(0x12345678);
1448       GrowableArray<Symbol*>* all_symbols = MetaspaceShared::collected_symbols();
1449       all_symbols->sort(compare_symbols_by_address);
1450       for (int i = 0; i < all_symbols->length(); i++) {
1451         assert(all_symbols->at(i)->is_permanent(), "archived symbols must be permanent");
1452         all_symbols->at(i)->update_identity_hash();
1453       }
1454     }
1455 #ifdef ASSERT
1456     {
1457       log_info(cds)("Verifying external roots ... ");
1458       ResourceMark rm;
1459       IsRefInArchiveChecker checker;
1460       iterate_roots(&checker);
1461     }
1462 #endif
1463   }
1464 
1465   // We must relocate the System::_well_known_klasses only after we have copied the
1466   // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1467   // old objects which assert that their klass is the original klass.
1468   static void relocate_well_known_klasses() {
1469     {
1470       log_info(cds)("Relocating SystemDictionary::_well_known_klasses[] ... ");
1471       ResourceMark rm;
1472       RefRelocator ext_reloc;
1473       SystemDictionary::well_known_klasses_do(&ext_reloc);
1474     }
1475     // NOTE: after this point, we shouldn't have any globals that can reach the old
1476     // objects.
1477 
1478     // We cannot use any of the objects in the heap anymore (except for the
1479     // shared strings) because their headers no longer point to valid Klasses.
1480   }
1481 
1482   static void iterate_roots(MetaspaceClosure* it) {
1483     // To ensure deterministic contents in the archive, we just need to ensure that
1484     // we iterate the MetsapceObjs in a deterministic order. It doesn't matter where
1485     // the MetsapceObjs are located originally, as they are copied sequentially into
1486     // the archive during the iteration.
1487     //
1488     // The only issue here is that the symbol table and the system directories may be
1489     // randomly ordered, so we copy the symbols and klasses into two arrays and sort
1490     // them deterministically.
1491     //
1492     // During -Xshare:dump, the order of Symbol creation is strictly determined by
1493     // the SharedClassListFile (class loading is done in a single thread and the JIT
1494     // is disabled). Also, Symbols are allocated in monotonically increasing addresses
1495     // (see Symbol::operator new(size_t, int)). So if we iterate the Symbols by
1496     // ascending address order, we ensure that all Symbols are copied into deterministic
1497     // locations in the archive.
1498     GrowableArray<Symbol*>* symbols = _global_symbol_objects;
1499     for (int i = 0; i < symbols->length(); i++) {
1500       it->push(symbols->adr_at(i));
1501     }
1502     if (_global_klass_objects != NULL) {
1503       // Need to fix up the pointers
1504       for (int i = 0; i < _global_klass_objects->length(); i++) {
1505         // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1506         it->push(_global_klass_objects->adr_at(i));
1507       }
1508     }
1509     FileMapInfo::metaspace_pointers_do(it, false);
1510     SystemDictionaryShared::dumptime_classes_do(it);
1511     Universe::metaspace_pointers_do(it);
1512     SymbolTable::metaspace_pointers_do(it);
1513     vmSymbols::metaspace_pointers_do(it);
1514 
1515     it->finish();
1516   }
1517 
1518   static Klass* get_relocated_klass(Klass* orig_klass) {
1519     assert(DumpSharedSpaces, "dump time only");
1520     address* pp = _new_loc_table->lookup((address)orig_klass);
1521     assert(pp != NULL, "must be");
1522     Klass* klass = (Klass*)(*pp);
1523     assert(klass->is_klass(), "must be");
1524     return klass;
1525   }
1526 };
1527 
1528 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1529 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1530 
1531 void VM_PopulateDumpSharedSpace::dump_symbols() {
1532   log_info(cds)("Dumping symbol table ...");
1533 
1534   NOT_PRODUCT(SymbolTable::verify());
1535   SymbolTable::write_to_archive();
1536 }
1537 
1538 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1539   ArchiveCompactor::OtherROAllocMark mark;
1540 
1541   log_info(cds)("Removing java_mirror ... ");
1542   if (!HeapShared::is_heap_object_archiving_allowed()) {
1543     clear_basic_type_mirrors();
1544   }
1545   remove_java_mirror_in_classes();
1546   log_info(cds)("done. ");
1547 
1548   SystemDictionaryShared::write_to_archive();
1549 
1550   // Write the other data to the output array.
1551   char* start = _ro_region.top();
1552   WriteClosure wc(&_ro_region);
1553   MetaspaceShared::serialize(&wc);
1554 
1555   // Write the bitmaps for patching the archive heap regions
1556   _closed_archive_heap_oopmaps = NULL;
1557   _open_archive_heap_oopmaps = NULL;
1558   dump_archive_heap_oopmaps();
1559 
1560   return start;
1561 }
1562 
1563 void VM_PopulateDumpSharedSpace::print_class_stats() {
1564   log_info(cds)("Number of classes %d", _global_klass_objects->length());
1565   {
1566     int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1567     for (int i = 0; i < _global_klass_objects->length(); i++) {
1568       Klass* k = _global_klass_objects->at(i);
1569       if (k->is_instance_klass()) {
1570         num_inst ++;
1571       } else if (k->is_objArray_klass()) {
1572         num_obj_array ++;
1573       } else {
1574         assert(k->is_typeArray_klass(), "sanity");
1575         num_type_array ++;
1576       }
1577     }
1578     log_info(cds)("    instance classes   = %5d", num_inst);
1579     log_info(cds)("    obj array classes  = %5d", num_obj_array);
1580     log_info(cds)("    type array classes = %5d", num_type_array);
1581   }
1582 }
1583 
1584 void VM_PopulateDumpSharedSpace::relocate_to_requested_base_address(CHeapBitMap* ptrmap) {
1585   intx addr_delta = MetaspaceShared::final_delta();
1586   if (addr_delta == 0) {
1587     ArchivePtrMarker::compact((address)SharedBaseAddress, (address)_ro_region.top());
1588   } else {
1589     // We are not able to reserve space at MetaspaceShared::requested_base_address() (due to ASLR).
1590     // This means that the current content of the archive is based on a random
1591     // address. Let's relocate all the pointers, so that it can be mapped to
1592     // MetaspaceShared::requested_base_address() without runtime relocation.
1593     //
1594     // Note: both the base and dynamic archive are written with
1595     // FileMapHeader::_requested_base_address == MetaspaceShared::requested_base_address()
1596 
1597     // Patch all pointers that are marked by ptrmap within this region,
1598     // where we have just dumped all the metaspace data.
1599     address patch_base = (address)SharedBaseAddress;
1600     address patch_end  = (address)_ro_region.top();
1601     size_t size = patch_end - patch_base;
1602 
1603     // the current value of the pointers to be patched must be within this
1604     // range (i.e., must point to valid metaspace objects)
1605     address valid_old_base = patch_base;
1606     address valid_old_end  = patch_end;
1607 
1608     // after patching, the pointers must point inside this range
1609     // (the requested location of the archive, as mapped at runtime).
1610     address valid_new_base = (address)MetaspaceShared::requested_base_address();
1611     address valid_new_end  = valid_new_base + size;
1612 
1613     log_debug(cds)("Relocating archive from [" INTPTR_FORMAT " - " INTPTR_FORMAT " ] to "
1614                    "[" INTPTR_FORMAT " - " INTPTR_FORMAT " ]", p2i(patch_base), p2i(patch_end),
1615                    p2i(valid_new_base), p2i(valid_new_end));
1616 
1617     SharedDataRelocator<true> patcher((address*)patch_base, (address*)patch_end, valid_old_base, valid_old_end,
1618                                       valid_new_base, valid_new_end, addr_delta, ptrmap);
1619     ptrmap->iterate(&patcher);
1620     ArchivePtrMarker::compact(patcher.max_non_null_offset());
1621   }
1622 }
1623 
1624 void VM_PopulateDumpSharedSpace::doit() {
1625   HeapShared::run_full_gc_in_vm_thread();
1626   CHeapBitMap ptrmap;
1627   MetaspaceShared::initialize_ptr_marker(&ptrmap);
1628 
1629   // We should no longer allocate anything from the metaspace, so that:
1630   //
1631   // (1) Metaspace::allocate might trigger GC if we have run out of
1632   //     committed metaspace, but we can't GC because we're running
1633   //     in the VM thread.
1634   // (2) ArchiveCompactor needs to work with a stable set of MetaspaceObjs.
1635   Metaspace::freeze();
1636   DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
1637 
1638   Thread* THREAD = VMThread::vm_thread();
1639 
1640   FileMapInfo::check_nonempty_dir_in_shared_path_table();
1641 
1642   NOT_PRODUCT(SystemDictionary::verify();)
1643   // The following guarantee is meant to ensure that no loader constraints
1644   // exist yet, since the constraints table is not shared.  This becomes
1645   // more important now that we don't re-initialize vtables/itables for
1646   // shared classes at runtime, where constraints were previously created.
1647   guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1648             "loader constraints are not saved");
1649   guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1650           "placeholders are not saved");
1651 
1652   // At this point, many classes have been loaded.
1653   // Gather systemDictionary classes in a global array and do everything to
1654   // that so we don't have to walk the SystemDictionary again.
1655   SystemDictionaryShared::check_excluded_classes();
1656   _global_klass_objects = new GrowableArray<Klass*>(1000);
1657   CollectClassesClosure collect_classes;
1658   ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1659   _global_klass_objects->sort(global_klass_compare);
1660 
1661   print_class_stats();
1662 
1663   // Ensure the ConstMethods won't be modified at run-time
1664   log_info(cds)("Updating ConstMethods ... ");
1665   rewrite_nofast_bytecodes_and_calculate_fingerprints(THREAD);
1666   log_info(cds)("done. ");
1667 
1668   // Remove all references outside the metadata
1669   log_info(cds)("Removing unshareable information ... ");
1670   remove_unshareable_in_classes();
1671   log_info(cds)("done. ");
1672 
1673   MetaspaceShared::allocate_cloned_cpp_vtptrs();
1674   char* cloned_vtables = _mc_region.top();
1675   MetaspaceShared::allocate_cpp_vtable_clones();
1676 
1677   ArchiveCompactor::initialize();
1678   ArchiveCompactor::copy_and_compact();
1679 
1680   dump_symbols();
1681 
1682   // Dump supported java heap objects
1683   _closed_archive_heap_regions = NULL;
1684   _open_archive_heap_regions = NULL;
1685   dump_java_heap_objects();
1686 
1687   ArchiveCompactor::relocate_well_known_klasses();
1688 
1689   char* serialized_data = dump_read_only_tables();
1690   _ro_region.pack();
1691 
1692   // The vtable clones contain addresses of the current process.
1693   // We don't want to write these addresses into the archive. Same for i2i buffer.
1694   MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1695   memset(MetaspaceShared::i2i_entry_code_buffers(), 0,
1696          MetaspaceShared::i2i_entry_code_buffers_size());
1697 
1698   // relocate the data so that it can be mapped to MetaspaceShared::requested_base_address()
1699   // without runtime relocation.
1700   relocate_to_requested_base_address(&ptrmap);
1701 
1702   // Create and write the archive file that maps the shared spaces.
1703 
1704   FileMapInfo* mapinfo = new FileMapInfo(true);
1705   mapinfo->populate_header(os::vm_allocation_granularity());
1706   mapinfo->set_serialized_data(serialized_data);
1707   mapinfo->set_cloned_vtables(cloned_vtables);
1708   mapinfo->set_i2i_entry_code_buffers(MetaspaceShared::i2i_entry_code_buffers(),
1709                                       MetaspaceShared::i2i_entry_code_buffers_size());
1710   mapinfo->open_for_write();
1711   MetaspaceShared::write_core_archive_regions(mapinfo, _closed_archive_heap_oopmaps, _open_archive_heap_oopmaps);
1712   _total_closed_archive_region_size = mapinfo->write_archive_heap_regions(
1713                                         _closed_archive_heap_regions,
1714                                         _closed_archive_heap_oopmaps,
1715                                         MetaspaceShared::first_closed_archive_heap_region,
1716                                         MetaspaceShared::max_closed_archive_heap_region);
1717   _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1718                                         _open_archive_heap_regions,
1719                                         _open_archive_heap_oopmaps,
1720                                         MetaspaceShared::first_open_archive_heap_region,
1721                                         MetaspaceShared::max_open_archive_heap_region);
1722 
1723   mapinfo->set_final_requested_base((char*)MetaspaceShared::requested_base_address());
1724   mapinfo->set_header_crc(mapinfo->compute_header_crc());
1725   mapinfo->write_header();
1726   print_region_stats(mapinfo);
1727   mapinfo->close();
1728 
1729   if (log_is_enabled(Info, cds)) {
1730     ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1731                                                  int(_mc_region.used()));
1732   }
1733 
1734   if (PrintSystemDictionaryAtExit) {
1735     SystemDictionary::print();
1736   }
1737 
1738   if (AllowArchivingWithJavaAgent) {
1739     warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
1740             "for testing purposes only and should not be used in a production environment");
1741   }
1742 
1743   // There may be other pending VM operations that operate on the InstanceKlasses,
1744   // which will fail because InstanceKlasses::remove_unshareable_info()
1745   // has been called. Forget these operations and exit the VM directly.
1746   vm_direct_exit(0);
1747 }
1748 
1749 void VM_PopulateDumpSharedSpace::print_region_stats(FileMapInfo *map_info) {
1750   // Print statistics of all the regions
1751   const size_t bitmap_used = map_info->space_at(MetaspaceShared::bm)->used();
1752   const size_t bitmap_reserved = map_info->space_at(MetaspaceShared::bm)->used_aligned();
1753   const size_t total_reserved = _ro_region.reserved()  + _rw_region.reserved() +
1754                                 _mc_region.reserved()  +
1755                                 bitmap_reserved +
1756                                 _total_closed_archive_region_size +
1757                                 _total_open_archive_region_size;
1758   const size_t total_bytes = _ro_region.used()  + _rw_region.used() +
1759                              _mc_region.used()  +
1760                              bitmap_used +
1761                              _total_closed_archive_region_size +
1762                              _total_open_archive_region_size;
1763   const double total_u_perc = percent_of(total_bytes, total_reserved);
1764 
1765   _mc_region.print(total_reserved);
1766   _rw_region.print(total_reserved);
1767   _ro_region.print(total_reserved);
1768   print_bitmap_region_stats(bitmap_used, total_reserved);
1769   print_heap_region_stats(_closed_archive_heap_regions, "ca", total_reserved);
1770   print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1771 
1772   log_debug(cds)("total    : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1773                  total_bytes, total_reserved, total_u_perc);
1774 }
1775 
1776 void VM_PopulateDumpSharedSpace::print_bitmap_region_stats(size_t size, size_t total_size) {
1777   log_debug(cds)("bm  space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [100.0%% used]",
1778                  size, size/double(total_size)*100.0, size);
1779 }
1780 
1781 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1782                                                          const char *name, size_t total_size) {
1783   int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1784   for (int i = 0; i < arr_len; i++) {
1785       char* start = (char*)heap_mem->at(i).start();
1786       size_t size = heap_mem->at(i).byte_size();
1787       char* top = start + size;
1788       log_debug(cds)("%s%d space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [100.0%% used] at " INTPTR_FORMAT,
1789                      name, i, size, size/double(total_size)*100.0, size, p2i(start));
1790 
1791   }
1792 }
1793 
1794 void MetaspaceShared::write_core_archive_regions(FileMapInfo* mapinfo,
1795                                                  GrowableArray<ArchiveHeapOopmapInfo>* closed_oopmaps,
1796                                                  GrowableArray<ArchiveHeapOopmapInfo>* open_oopmaps) {
1797   // Make sure NUM_CDS_REGIONS (exported in cds.h) agrees with
1798   // MetaspaceShared::n_regions (internal to hotspot).
1799   assert(NUM_CDS_REGIONS == MetaspaceShared::n_regions, "sanity");
1800 
1801   // mc contains the trampoline code for method entries, which are patched at run time,
1802   // so it needs to be read/write.
1803   write_region(mapinfo, mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1804   write_region(mapinfo, rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1805   write_region(mapinfo, ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1806   mapinfo->write_bitmap_region(ArchivePtrMarker::ptrmap(), closed_oopmaps, open_oopmaps);
1807 }
1808 
1809 void MetaspaceShared::write_region(FileMapInfo* mapinfo, int region_idx, DumpRegion* dump_region, bool read_only,  bool allow_exec) {
1810   mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1811 }
1812 
1813 // Update a Java object to point its Klass* to the new location after
1814 // shared archive has been compacted.
1815 void MetaspaceShared::relocate_klass_ptr(oop o) {
1816   assert(DumpSharedSpaces, "sanity");
1817   Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1818   o->set_klass(k);
1819 }
1820 
1821 Klass* MetaspaceShared::get_relocated_klass(Klass *k, bool is_final) {
1822   assert(DumpSharedSpaces, "sanity");
1823   k = ArchiveCompactor::get_relocated_klass(k);
1824   if (is_final) {
1825     k = (Klass*)(address(k) + final_delta());
1826   }
1827   return k;
1828 }
1829 
1830 class LinkSharedClassesClosure : public KlassClosure {
1831   Thread* THREAD;
1832   bool    _made_progress;
1833  public:
1834   LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1835 
1836   void reset()               { _made_progress = false; }
1837   bool made_progress() const { return _made_progress; }
1838 
1839   void do_klass(Klass* k) {
1840     if (k->is_instance_klass()) {
1841       InstanceKlass* ik = InstanceKlass::cast(k);
1842       // For dynamic CDS dump, only link classes loaded by the builtin class loaders.
1843       bool do_linking = DumpSharedSpaces ? true : !ik->is_shared_unregistered_class();
1844       if (do_linking) {
1845         // Link the class to cause the bytecodes to be rewritten and the
1846         // cpcache to be created. Class verification is done according
1847         // to -Xverify setting.
1848         _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1849         guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1850 
1851         if (DumpSharedSpaces) {
1852           // The following function is used to resolve all Strings in the statically
1853           // dumped classes to archive all the Strings. The archive heap is not supported
1854           // for the dynamic archive.
1855           ik->constants()->resolve_class_constants(THREAD);
1856         }
1857       }
1858     }
1859   }
1860 };
1861 
1862 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1863   // We need to iterate because verification may cause additional classes
1864   // to be loaded.
1865   LinkSharedClassesClosure link_closure(THREAD);
1866   do {
1867     link_closure.reset();
1868     ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1869     guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1870   } while (link_closure.made_progress());
1871 }
1872 
1873 void MetaspaceShared::prepare_for_dumping() {
1874   Arguments::check_unsupported_dumping_properties();
1875   ClassLoader::initialize_shared_path();
1876 }
1877 
1878 // Preload classes from a list, populate the shared spaces and dump to a
1879 // file.
1880 void MetaspaceShared::preload_and_dump(TRAPS) {
1881   { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1882     ResourceMark rm(THREAD);
1883     char class_list_path_str[JVM_MAXPATHLEN];
1884     // Preload classes to be shared.
1885     const char* class_list_path;
1886     if (SharedClassListFile == NULL) {
1887       // Construct the path to the class list (in jre/lib)
1888       // Walk up two directories from the location of the VM and
1889       // optionally tack on "lib" (depending on platform)
1890       os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1891       for (int i = 0; i < 3; i++) {
1892         char *end = strrchr(class_list_path_str, *os::file_separator());
1893         if (end != NULL) *end = '\0';
1894       }
1895       int class_list_path_len = (int)strlen(class_list_path_str);
1896       if (class_list_path_len >= 3) {
1897         if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1898           if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1899             jio_snprintf(class_list_path_str + class_list_path_len,
1900                          sizeof(class_list_path_str) - class_list_path_len,
1901                          "%slib", os::file_separator());
1902             class_list_path_len += 4;
1903           }
1904         }
1905       }
1906       if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1907         jio_snprintf(class_list_path_str + class_list_path_len,
1908                      sizeof(class_list_path_str) - class_list_path_len,
1909                      "%sclasslist", os::file_separator());
1910       }
1911       class_list_path = class_list_path_str;
1912     } else {
1913       class_list_path = SharedClassListFile;
1914     }
1915 
1916     log_info(cds)("Loading classes to share ...");
1917     _has_error_classes = false;
1918     int class_count = preload_classes(class_list_path, THREAD);
1919     if (ExtraSharedClassListFile) {
1920       class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1921     }
1922     log_info(cds)("Loading classes to share: done.");
1923 
1924     log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1925 
1926     if (SharedArchiveConfigFile) {
1927       log_info(cds)("Reading extra data from %s ...", SharedArchiveConfigFile);
1928       read_extra_data(SharedArchiveConfigFile, THREAD);
1929     }
1930     log_info(cds)("Reading extra data: done.");
1931 
1932     HeapShared::init_subgraph_entry_fields(THREAD);
1933 
1934     // Rewrite and link classes
1935     log_info(cds)("Rewriting and linking classes ...");
1936 
1937     // Link any classes which got missed. This would happen if we have loaded classes that
1938     // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1939     // fails verification, all other interfaces that were not specified in the classlist but
1940     // are implemented by K are not verified.
1941     link_and_cleanup_shared_classes(CATCH);
1942     log_info(cds)("Rewriting and linking classes: done");
1943 
1944     VM_PopulateDumpSharedSpace op;
1945     MutexLocker ml(THREAD, HeapShared::is_heap_object_archiving_allowed() ?
1946                    Heap_lock : NULL);     // needed by HeapShared::run_gc()
1947     VMThread::execute(&op);
1948   }
1949 }
1950 
1951 
1952 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1953   ClassListParser parser(class_list_path);
1954   int class_count = 0;
1955 
1956   while (parser.parse_one_line()) {
1957     Klass* klass = parser.load_current_class(THREAD);
1958     if (HAS_PENDING_EXCEPTION) {
1959       if (klass == NULL &&
1960           (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1961         // print a warning only when the pending exception is class not found
1962         log_warning(cds)("Preload Warning: Cannot find %s", parser.current_class_name());
1963       }
1964       CLEAR_PENDING_EXCEPTION;
1965     }
1966     if (klass != NULL) {
1967       if (log_is_enabled(Trace, cds)) {
1968         ResourceMark rm(THREAD);
1969         log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1970       }
1971 
1972       if (klass->is_instance_klass()) {
1973         InstanceKlass* ik = InstanceKlass::cast(klass);
1974 
1975         // Link the class to cause the bytecodes to be rewritten and the
1976         // cpcache to be created. The linking is done as soon as classes
1977         // are loaded in order that the related data structures (klass and
1978         // cpCache) are located together.
1979         try_link_class(ik, THREAD);
1980         guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1981       }
1982 
1983       class_count++;
1984     }
1985   }
1986 
1987   return class_count;
1988 }
1989 
1990 // Returns true if the class's status has changed
1991 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1992   Arguments::assert_is_dumping_archive();
1993   if (ik->init_state() < InstanceKlass::linked &&
1994       !SystemDictionaryShared::has_class_failed_verification(ik)) {
1995     bool saved = BytecodeVerificationLocal;
1996     if (ik->is_shared_unregistered_class() && ik->class_loader() == NULL) {
1997       // The verification decision is based on BytecodeVerificationRemote
1998       // for non-system classes. Since we are using the NULL classloader
1999       // to load non-system classes for customized class loaders during dumping,
2000       // we need to temporarily change BytecodeVerificationLocal to be the same as
2001       // BytecodeVerificationRemote. Note this can cause the parent system
2002       // classes also being verified. The extra overhead is acceptable during
2003       // dumping.
2004       BytecodeVerificationLocal = BytecodeVerificationRemote;
2005     }
2006     ik->link_class(THREAD);
2007     if (HAS_PENDING_EXCEPTION) {
2008       ResourceMark rm(THREAD);
2009       log_warning(cds)("Preload Warning: Verification failed for %s",
2010                     ik->external_name());
2011       CLEAR_PENDING_EXCEPTION;
2012       SystemDictionaryShared::set_class_has_failed_verification(ik);
2013       _has_error_classes = true;
2014     }
2015     BytecodeVerificationLocal = saved;
2016     return true;
2017   } else {
2018     return false;
2019   }
2020 }
2021 
2022 #if INCLUDE_CDS_JAVA_HEAP
2023 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
2024   // The closed and open archive heap space has maximum two regions.
2025   // See FileMapInfo::write_archive_heap_regions() for details.
2026   _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
2027   _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
2028   HeapShared::archive_java_heap_objects(_closed_archive_heap_regions,
2029                                         _open_archive_heap_regions);
2030   ArchiveCompactor::OtherROAllocMark mark;
2031   HeapShared::write_subgraph_info_table();
2032 }
2033 
2034 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
2035   if (HeapShared::is_heap_object_archiving_allowed()) {
2036     _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
2037     dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
2038 
2039     _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
2040     dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
2041   }
2042 }
2043 
2044 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
2045                                                            GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
2046   for (int i=0; i<regions->length(); i++) {
2047     ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
2048     size_t size_in_bits = oopmap.size();
2049     size_t size_in_bytes = oopmap.size_in_bytes();
2050     uintptr_t* buffer = (uintptr_t*)NEW_C_HEAP_ARRAY(char, size_in_bytes, mtInternal);
2051     oopmap.write_to(buffer, size_in_bytes);
2052     log_info(cds, heap)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
2053                         INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
2054                         p2i(buffer), size_in_bytes,
2055                         p2i(regions->at(i).start()), regions->at(i).byte_size());
2056 
2057     ArchiveHeapOopmapInfo info;
2058     info._oopmap = (address)buffer;
2059     info._oopmap_size_in_bits = size_in_bits;
2060     info._oopmap_size_in_bytes = size_in_bytes;
2061     oopmaps->append(info);
2062   }
2063 }
2064 #endif // INCLUDE_CDS_JAVA_HEAP
2065 
2066 void ReadClosure::do_ptr(void** p) {
2067   assert(*p == NULL, "initializing previous initialized pointer.");
2068   intptr_t obj = nextPtr();
2069   assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
2070          "hit tag while initializing ptrs.");
2071   *p = (void*)obj;
2072 }
2073 
2074 void ReadClosure::do_u4(u4* p) {
2075   intptr_t obj = nextPtr();
2076   *p = (u4)(uintx(obj));
2077 }
2078 
2079 void ReadClosure::do_bool(bool* p) {
2080   intptr_t obj = nextPtr();
2081   *p = (bool)(uintx(obj));
2082 }
2083 
2084 void ReadClosure::do_tag(int tag) {
2085   int old_tag;
2086   old_tag = (int)(intptr_t)nextPtr();
2087   // do_int(&old_tag);
2088   assert(tag == old_tag, "old tag doesn't match");
2089   FileMapInfo::assert_mark(tag == old_tag);
2090 }
2091 
2092 void ReadClosure::do_oop(oop *p) {
2093   narrowOop o = (narrowOop)nextPtr();
2094   if (o == 0 || !HeapShared::open_archive_heap_region_mapped()) {
2095     p = NULL;
2096   } else {
2097     assert(HeapShared::is_heap_object_archiving_allowed(),
2098            "Archived heap object is not allowed");
2099     assert(HeapShared::open_archive_heap_region_mapped(),
2100            "Open archive heap region is not mapped");
2101     *p = HeapShared::decode_from_archive(o);
2102   }
2103 }
2104 
2105 void ReadClosure::do_region(u_char* start, size_t size) {
2106   assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
2107   assert(size % sizeof(intptr_t) == 0, "bad size");
2108   do_tag((int)size);
2109   while (size > 0) {
2110     *(intptr_t*)start = nextPtr();
2111     start += sizeof(intptr_t);
2112     size -= sizeof(intptr_t);
2113   }
2114 }
2115 
2116 void MetaspaceShared::set_shared_metaspace_range(void* base, void *static_top, void* top) {
2117   assert(base <= static_top && static_top <= top, "must be");
2118   _shared_metaspace_static_top = static_top;
2119   MetaspaceObj::set_shared_metaspace_range(base, top);
2120 }
2121 
2122 // Return true if given address is in the misc data region
2123 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
2124   return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
2125 }
2126 
2127 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
2128   if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
2129     return true;
2130   }
2131   return false;
2132 }
2133 
2134 bool MetaspaceShared::is_shared_dynamic(void* p) {
2135   if ((p < MetaspaceObj::shared_metaspace_top()) &&
2136       (p >= _shared_metaspace_static_top)) {
2137     return true;
2138   } else {
2139     return false;
2140   }
2141 }
2142 
2143 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
2144   assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
2145   MapArchiveResult result = MAP_ARCHIVE_OTHER_FAILURE;
2146 
2147   FileMapInfo* static_mapinfo = open_static_archive();
2148   FileMapInfo* dynamic_mapinfo = NULL;
2149 
2150   if (static_mapinfo != NULL) {
2151     dynamic_mapinfo = open_dynamic_archive();
2152 
2153     // First try to map at the requested address
2154     result = map_archives(static_mapinfo, dynamic_mapinfo, true);
2155     if (result == MAP_ARCHIVE_MMAP_FAILURE) {
2156       // Mapping has failed (probably due to ASLR). Let's map at an address chosen
2157       // by the OS.
2158       log_info(cds)("Try to map archive(s) at an alternative address");
2159       result = map_archives(static_mapinfo, dynamic_mapinfo, false);
2160     }
2161   }
2162 
2163   if (result == MAP_ARCHIVE_SUCCESS) {
2164     bool dynamic_mapped = (dynamic_mapinfo != NULL && dynamic_mapinfo->is_mapped());
2165     char* cds_base = static_mapinfo->mapped_base();
2166     char* cds_end =  dynamic_mapped ? dynamic_mapinfo->mapped_end() : static_mapinfo->mapped_end();
2167     set_shared_metaspace_range(cds_base, static_mapinfo->mapped_end(), cds_end);
2168     _relocation_delta = static_mapinfo->relocation_delta();
2169     if (dynamic_mapped) {
2170       FileMapInfo::set_shared_path_table(dynamic_mapinfo);
2171     } else {
2172       FileMapInfo::set_shared_path_table(static_mapinfo);
2173     }
2174     _requested_base_address = static_mapinfo->requested_base_address();
2175   } else {
2176     set_shared_metaspace_range(NULL, NULL, NULL);
2177     UseSharedSpaces = false;
2178     FileMapInfo::fail_continue("Unable to map shared spaces");
2179     if (PrintSharedArchiveAndExit) {
2180       vm_exit_during_initialization("Unable to use shared archive.");
2181     }
2182   }
2183 
2184   if (static_mapinfo != NULL && !static_mapinfo->is_mapped()) {
2185     delete static_mapinfo;
2186   }
2187   if (dynamic_mapinfo != NULL && !dynamic_mapinfo->is_mapped()) {
2188     delete dynamic_mapinfo;
2189   }
2190 }
2191 
2192 FileMapInfo* MetaspaceShared::open_static_archive() {
2193   FileMapInfo* mapinfo = new FileMapInfo(true);
2194   if (!mapinfo->initialize()) {
2195     delete(mapinfo);
2196     return NULL;
2197   }
2198   return mapinfo;
2199 }
2200 
2201 FileMapInfo* MetaspaceShared::open_dynamic_archive() {
2202   if (DynamicDumpSharedSpaces) {
2203     return NULL;
2204   }
2205   if (Arguments::GetSharedDynamicArchivePath() == NULL) {
2206     return NULL;
2207   }
2208 
2209   FileMapInfo* mapinfo = new FileMapInfo(false);
2210   if (!mapinfo->initialize()) {
2211     delete(mapinfo);
2212     return NULL;
2213   }
2214   return mapinfo;
2215 }
2216 
2217 // use_requested_addr:
2218 //  true  = map at FileMapHeader::_requested_base_address
2219 //  false = map at an alternative address picked by OS.
2220 MapArchiveResult MetaspaceShared::map_archives(FileMapInfo* static_mapinfo, FileMapInfo* dynamic_mapinfo,
2221                                                bool use_requested_addr) {
2222   if (use_requested_addr && static_mapinfo->requested_base_address() == NULL) {
2223     log_info(cds)("Archive(s) were created with -XX:SharedBaseAddress=0. Always map at os-selected address.");
2224     return MAP_ARCHIVE_MMAP_FAILURE;
2225   }
2226 
2227   PRODUCT_ONLY(if (ArchiveRelocationMode == 1 && use_requested_addr) {
2228       // For product build only -- this is for benchmarking the cost of doing relocation.
2229       // For debug builds, the check is done below, after reserving the space, for better test coverage
2230       // (see comment below).
2231       log_info(cds)("ArchiveRelocationMode == 1: always map archive(s) at an alternative address");
2232       return MAP_ARCHIVE_MMAP_FAILURE;
2233     });
2234 
2235   if (ArchiveRelocationMode == 2 && !use_requested_addr) {
2236     log_info(cds)("ArchiveRelocationMode == 2: never map archive(s) at an alternative address");
2237     return MAP_ARCHIVE_MMAP_FAILURE;
2238   };
2239 
2240   if (dynamic_mapinfo != NULL) {
2241     // Ensure that the OS won't be able to allocate new memory spaces between the two
2242     // archives, or else it would mess up the simple comparision in MetaspaceObj::is_shared().
2243     assert(static_mapinfo->mapping_end_offset() == dynamic_mapinfo->mapping_base_offset(), "no gap");
2244   }
2245 
2246   ReservedSpace archive_space_rs, class_space_rs;
2247   MapArchiveResult result = MAP_ARCHIVE_OTHER_FAILURE;
2248   char* mapped_base_address = reserve_address_space_for_archives(static_mapinfo, dynamic_mapinfo,
2249                                                                  use_requested_addr, archive_space_rs,
2250                                                                  class_space_rs);
2251   if (mapped_base_address == NULL) {
2252     result = MAP_ARCHIVE_MMAP_FAILURE;
2253     log_debug(cds)("Failed to reserve spaces (use_requested_addr=%u)", (unsigned)use_requested_addr);
2254   } else {
2255 
2256 #ifdef ASSERT
2257     // Some sanity checks after reserving address spaces for archives
2258     //  and class space.
2259     assert(archive_space_rs.is_reserved(), "Sanity");
2260     if (Metaspace::using_class_space()) {
2261       // Class space must closely follow the archive space. Both spaces
2262       //  must be aligned correctly.
2263       assert(class_space_rs.is_reserved(),
2264              "A class space should have been reserved");
2265       assert(class_space_rs.base() >= archive_space_rs.end(),
2266              "class space should follow the cds archive space");
2267       assert(is_aligned(archive_space_rs.base(),
2268                         MetaspaceShared::reserved_space_alignment()),
2269              "Archive space misaligned");
2270       assert(is_aligned(class_space_rs.base(),
2271                         Metaspace::reserve_alignment()),
2272              "class space misaligned");
2273     }
2274 #endif // ASSERT
2275 
2276     log_debug(cds)("Reserved archive_space_rs     [" INTPTR_FORMAT " - " INTPTR_FORMAT "] (" SIZE_FORMAT ") bytes",
2277                    p2i(archive_space_rs.base()), p2i(archive_space_rs.end()), archive_space_rs.size());
2278     log_debug(cds)("Reserved class_space_rs [" INTPTR_FORMAT " - " INTPTR_FORMAT "] (" SIZE_FORMAT ") bytes",
2279                    p2i(class_space_rs.base()), p2i(class_space_rs.end()), class_space_rs.size());
2280 
2281     if (MetaspaceShared::use_windows_memory_mapping()) {
2282       // We have now reserved address space for the archives, and will map in
2283       //  the archive files into this space.
2284       //
2285       // Special handling for Windows: on Windows we cannot map a file view
2286       //  into an existing memory mapping. So, we unmap the address range we
2287       //  just reserved again, which will make it available for mapping the
2288       //  archives.
2289       // Reserving this range has not been for naught however since it makes
2290       //  us reasonably sure the address range is available.
2291       //
2292       // But still it may fail, since between unmapping the range and mapping
2293       //  in the archive someone else may grab the address space. Therefore
2294       //  there is a fallback in FileMap::map_region() where we just read in
2295       //  the archive files sequentially instead of mapping it in. We couple
2296       //  this with use_requested_addr, since we're going to patch all the
2297       //  pointers anyway so there's no benefit to mmap.
2298       if (use_requested_addr) {
2299         log_info(cds)("Windows mmap workaround: releasing archive space.");
2300         archive_space_rs.release();
2301       }
2302     }
2303     MapArchiveResult static_result = map_archive(static_mapinfo, mapped_base_address, archive_space_rs);
2304     MapArchiveResult dynamic_result = (static_result == MAP_ARCHIVE_SUCCESS) ?
2305                                      map_archive(dynamic_mapinfo, mapped_base_address, archive_space_rs) : MAP_ARCHIVE_OTHER_FAILURE;
2306 
2307     DEBUG_ONLY(if (ArchiveRelocationMode == 1 && use_requested_addr) {
2308       // This is for simulating mmap failures at the requested address. In
2309       //  debug builds, we do it here (after all archives have possibly been
2310       //  mapped), so we can thoroughly test the code for failure handling
2311       //  (releasing all allocated resource, etc).
2312       log_info(cds)("ArchiveRelocationMode == 1: always map archive(s) at an alternative address");
2313       if (static_result == MAP_ARCHIVE_SUCCESS) {
2314         static_result = MAP_ARCHIVE_MMAP_FAILURE;
2315       }
2316       if (dynamic_result == MAP_ARCHIVE_SUCCESS) {
2317         dynamic_result = MAP_ARCHIVE_MMAP_FAILURE;
2318       }
2319     });
2320 
2321     if (static_result == MAP_ARCHIVE_SUCCESS) {
2322       if (dynamic_result == MAP_ARCHIVE_SUCCESS) {
2323         result = MAP_ARCHIVE_SUCCESS;
2324       } else if (dynamic_result == MAP_ARCHIVE_OTHER_FAILURE) {
2325         assert(dynamic_mapinfo != NULL && !dynamic_mapinfo->is_mapped(), "must have failed");
2326         // No need to retry mapping the dynamic archive again, as it will never succeed
2327         // (bad file, etc) -- just keep the base archive.
2328         log_warning(cds, dynamic)("Unable to use shared archive. The top archive failed to load: %s",
2329                                   dynamic_mapinfo->full_path());
2330         result = MAP_ARCHIVE_SUCCESS;
2331         // TODO, we can give the unused space for the dynamic archive to class_space_rs, but there's no
2332         // easy API to do that right now.
2333       } else {
2334         result = MAP_ARCHIVE_MMAP_FAILURE;
2335       }
2336     } else if (static_result == MAP_ARCHIVE_OTHER_FAILURE) {
2337       result = MAP_ARCHIVE_OTHER_FAILURE;
2338     } else {
2339       result = MAP_ARCHIVE_MMAP_FAILURE;
2340     }
2341   }
2342 
2343   if (result == MAP_ARCHIVE_SUCCESS) {
2344     SharedBaseAddress = (size_t)mapped_base_address;
2345     LP64_ONLY({
2346         if (Metaspace::using_class_space()) {
2347           // Set up ccs in metaspace.
2348           Metaspace::initialize_class_space(class_space_rs);
2349 
2350           // Set up compressed Klass pointer encoding: the encoding range must
2351           //  cover both archive and class space.
2352           address cds_base = (address)static_mapinfo->mapped_base();
2353           address ccs_end = (address)class_space_rs.end();
2354           CompressedKlassPointers::initialize(cds_base, ccs_end - cds_base);
2355 
2356           // map_heap_regions() compares the current narrow oop and klass encodings
2357           // with the archived ones, so it must be done after all encodings are determined.
2358           static_mapinfo->map_heap_regions();
2359         }
2360       });
2361     log_info(cds)("Using optimized module handling %s", MetaspaceShared::use_optimized_module_handling() ? "enabled" : "disabled");
2362   } else {
2363     unmap_archive(static_mapinfo);
2364     unmap_archive(dynamic_mapinfo);
2365     release_reserved_spaces(archive_space_rs, class_space_rs);
2366   }
2367 
2368   return result;
2369 }
2370 
2371 
2372 // This will reserve two address spaces suitable to house Klass structures, one
2373 //  for the cds archives (static archive and optionally dynamic archive) and
2374 //  optionally one move for ccs.
2375 //
2376 // Since both spaces must fall within the compressed class pointer encoding
2377 //  range, they are allocated close to each other.
2378 //
2379 // Space for archives will be reserved first, followed by a potential gap,
2380 //  followed by the space for ccs:
2381 //
2382 // +-- Base address             A        B                     End
2383 // |                            |        |                      |
2384 // v                            v        v                      v
2385 // +-------------+--------------+        +----------------------+
2386 // | static arc  | [dyn. arch]  | [gap]  | compr. class space   |
2387 // +-------------+--------------+        +----------------------+
2388 //
2389 // (The gap may result from different alignment requirements between metaspace
2390 //  and CDS)
2391 //
2392 // If UseCompressedClassPointers is disabled, only one address space will be
2393 //  reserved:
2394 //
2395 // +-- Base address             End
2396 // |                            |
2397 // v                            v
2398 // +-------------+--------------+
2399 // | static arc  | [dyn. arch]  |
2400 // +-------------+--------------+
2401 //
2402 // Base address: If use_archive_base_addr address is true, the Base address is
2403 //  determined by the address stored in the static archive. If
2404 //  use_archive_base_addr address is false, this base address is determined
2405 //  by the platform.
2406 //
2407 // If UseCompressedClassPointers=1, the range encompassing both spaces will be
2408 //  suitable to en/decode narrow Klass pointers: the base will be valid for
2409 //  encoding, the range [Base, End) not surpass KlassEncodingMetaspaceMax.
2410 //
2411 // Return:
2412 //
2413 // - On success:
2414 //    - archive_space_rs will be reserved and large enough to host static and
2415 //      if needed dynamic archive: [Base, A).
2416 //      archive_space_rs.base and size will be aligned to CDS reserve
2417 //      granularity.
2418 //    - class_space_rs: If UseCompressedClassPointers=1, class_space_rs will
2419 //      be reserved. Its start address will be aligned to metaspace reserve
2420 //      alignment, which may differ from CDS alignment. It will follow the cds
2421 //      archive space, close enough such that narrow class pointer encoding
2422 //      covers both spaces.
2423 //      If UseCompressedClassPointers=0, class_space_rs remains unreserved.
2424 // - On error: NULL is returned and the spaces remain unreserved.
2425 char* MetaspaceShared::reserve_address_space_for_archives(FileMapInfo* static_mapinfo,
2426                                                           FileMapInfo* dynamic_mapinfo,
2427                                                           bool use_archive_base_addr,
2428                                                           ReservedSpace& archive_space_rs,
2429                                                           ReservedSpace& class_space_rs) {
2430 
2431   address const base_address = (address) (use_archive_base_addr ? static_mapinfo->requested_base_address() : NULL);
2432   const size_t archive_space_alignment = MetaspaceShared::reserved_space_alignment();
2433 
2434   // Size and requested location of the archive_space_rs (for both static and dynamic archives)
2435   assert(static_mapinfo->mapping_base_offset() == 0, "Must be");
2436   size_t archive_end_offset  = (dynamic_mapinfo == NULL) ? static_mapinfo->mapping_end_offset() : dynamic_mapinfo->mapping_end_offset();
2437   size_t archive_space_size = align_up(archive_end_offset, archive_space_alignment);
2438 
2439   // If a base address is given, it must have valid alignment and be suitable as encoding base.
2440   if (base_address != NULL) {
2441     assert(is_aligned(base_address, archive_space_alignment),
2442            "Archive base address invalid: " PTR_FORMAT ".", p2i(base_address));
2443     if (Metaspace::using_class_space()) {
2444       assert(CompressedKlassPointers::is_valid_base(base_address),
2445              "Archive base address invalid: " PTR_FORMAT ".", p2i(base_address));
2446     }
2447   }
2448 
2449   if (!Metaspace::using_class_space()) {
2450     // Get the simple case out of the way first:
2451     // no compressed class space, simple allocation.
2452     archive_space_rs = ReservedSpace(archive_space_size, archive_space_alignment,
2453                                      false /* bool large */, (char*)base_address);
2454     if (archive_space_rs.is_reserved()) {
2455       assert(base_address == NULL ||
2456              (address)archive_space_rs.base() == base_address, "Sanity");
2457       // Register archive space with NMT.
2458       MemTracker::record_virtual_memory_type(archive_space_rs.base(), mtClassShared);
2459       return archive_space_rs.base();
2460     }
2461     return NULL;
2462   }
2463 
2464 #ifdef _LP64
2465 
2466   // Complex case: two spaces adjacent to each other, both to be addressable
2467   //  with narrow class pointers.
2468   // We reserve the whole range spanning both spaces, then split that range up.
2469 
2470   const size_t class_space_alignment = Metaspace::reserve_alignment();
2471 
2472   // To simplify matters, lets assume that metaspace alignment will always be
2473   //  equal or a multiple of archive alignment.
2474   assert(is_power_of_2(class_space_alignment) &&
2475                        is_power_of_2(archive_space_alignment) &&
2476                        class_space_alignment >= archive_space_alignment,
2477                        "Sanity");
2478 
2479   const size_t class_space_size = CompressedClassSpaceSize;
2480   assert(CompressedClassSpaceSize > 0 &&
2481          is_aligned(CompressedClassSpaceSize, class_space_alignment),
2482          "CompressedClassSpaceSize malformed: "
2483          SIZE_FORMAT, CompressedClassSpaceSize);
2484 
2485   const size_t ccs_begin_offset = align_up(base_address + archive_space_size,
2486                                            class_space_alignment) - base_address;
2487   const size_t gap_size = ccs_begin_offset - archive_space_size;
2488 
2489   const size_t total_range_size =
2490       align_up(archive_space_size + gap_size + class_space_size,
2491                os::vm_allocation_granularity());
2492 
2493   ReservedSpace total_rs;
2494   if (base_address != NULL) {
2495     // Reserve at the given archive base address, or not at all.
2496     total_rs = ReservedSpace(total_range_size, archive_space_alignment,
2497                              false /* bool large */, (char*) base_address);
2498   } else {
2499     // Reserve at any address, but leave it up to the platform to choose a good one.
2500     total_rs = Metaspace::reserve_address_space_for_compressed_classes(total_range_size);
2501   }
2502 
2503   if (!total_rs.is_reserved()) {
2504     return NULL;
2505   }
2506 
2507   // Paranoid checks:
2508   assert(base_address == NULL || (address)total_rs.base() == base_address,
2509          "Sanity (" PTR_FORMAT " vs " PTR_FORMAT ")", p2i(base_address), p2i(total_rs.base()));
2510   assert(is_aligned(total_rs.base(), archive_space_alignment), "Sanity");
2511   assert(total_rs.size() == total_range_size, "Sanity");
2512   assert(CompressedKlassPointers::is_valid_base((address)total_rs.base()), "Sanity");
2513 
2514   // Now split up the space into ccs and cds archive. For simplicity, just leave
2515   //  the gap reserved at the end of the archive space.
2516   archive_space_rs = total_rs.first_part(ccs_begin_offset,
2517                                          (size_t)os::vm_allocation_granularity(),
2518                                          /*split=*/true);
2519   class_space_rs = total_rs.last_part(ccs_begin_offset);
2520 
2521   assert(is_aligned(archive_space_rs.base(), archive_space_alignment), "Sanity");
2522   assert(is_aligned(archive_space_rs.size(), archive_space_alignment), "Sanity");
2523   assert(is_aligned(class_space_rs.base(), class_space_alignment), "Sanity");
2524   assert(is_aligned(class_space_rs.size(), class_space_alignment), "Sanity");
2525 
2526   // NMT: fix up the space tags
2527   MemTracker::record_virtual_memory_type(archive_space_rs.base(), mtClassShared);
2528   MemTracker::record_virtual_memory_type(class_space_rs.base(), mtClass);
2529 
2530   return archive_space_rs.base();
2531 
2532 #else
2533   ShouldNotReachHere();
2534   return NULL;
2535 #endif
2536 
2537 }
2538 
2539 void MetaspaceShared::release_reserved_spaces(ReservedSpace& archive_space_rs,
2540                                               ReservedSpace& class_space_rs) {
2541   if (archive_space_rs.is_reserved()) {
2542     log_debug(cds)("Released shared space (archive) " INTPTR_FORMAT, p2i(archive_space_rs.base()));
2543     archive_space_rs.release();
2544   }
2545   if (class_space_rs.is_reserved()) {
2546     log_debug(cds)("Released shared space (classes) " INTPTR_FORMAT, p2i(class_space_rs.base()));
2547     class_space_rs.release();
2548   }
2549 }
2550 
2551 static int archive_regions[]  = {MetaspaceShared::mc,
2552                                  MetaspaceShared::rw,
2553                                  MetaspaceShared::ro};
2554 static int archive_regions_count  = 3;
2555 
2556 MapArchiveResult MetaspaceShared::map_archive(FileMapInfo* mapinfo, char* mapped_base_address, ReservedSpace rs) {
2557   assert(UseSharedSpaces, "must be runtime");
2558   if (mapinfo == NULL) {
2559     return MAP_ARCHIVE_SUCCESS; // The dynamic archive has not been specified. No error has happened -- trivially succeeded.
2560   }
2561 
2562   mapinfo->set_is_mapped(false);
2563 
2564   if (mapinfo->alignment() != (size_t)os::vm_allocation_granularity()) {
2565     log_error(cds)("Unable to map CDS archive -- os::vm_allocation_granularity() expected: " SIZE_FORMAT
2566                    " actual: %d", mapinfo->alignment(), os::vm_allocation_granularity());
2567     return MAP_ARCHIVE_OTHER_FAILURE;
2568   }
2569 
2570   MapArchiveResult result =
2571     mapinfo->map_regions(archive_regions, archive_regions_count, mapped_base_address, rs);
2572 
2573   if (result != MAP_ARCHIVE_SUCCESS) {
2574     unmap_archive(mapinfo);
2575     return result;
2576   }
2577 
2578   if (!mapinfo->validate_shared_path_table()) {
2579     unmap_archive(mapinfo);
2580     return MAP_ARCHIVE_OTHER_FAILURE;
2581   }
2582 
2583   mapinfo->set_is_mapped(true);
2584   return MAP_ARCHIVE_SUCCESS;
2585 }
2586 
2587 void MetaspaceShared::unmap_archive(FileMapInfo* mapinfo) {
2588   assert(UseSharedSpaces, "must be runtime");
2589   if (mapinfo != NULL) {
2590     mapinfo->unmap_regions(archive_regions, archive_regions_count);
2591     mapinfo->set_is_mapped(false);
2592   }
2593 }
2594 
2595 // Read the miscellaneous data from the shared file, and
2596 // serialize it out to its various destinations.
2597 
2598 void MetaspaceShared::initialize_shared_spaces() {
2599   FileMapInfo *static_mapinfo = FileMapInfo::current_info();
2600   _i2i_entry_code_buffers = static_mapinfo->i2i_entry_code_buffers();
2601   _i2i_entry_code_buffers_size = static_mapinfo->i2i_entry_code_buffers_size();
2602   char* buffer = static_mapinfo->cloned_vtables();
2603   clone_cpp_vtables((intptr_t*)buffer);
2604 
2605   // Verify various attributes of the archive, plus initialize the
2606   // shared string/symbol tables
2607   buffer = static_mapinfo->serialized_data();
2608   intptr_t* array = (intptr_t*)buffer;
2609   ReadClosure rc(&array);
2610   serialize(&rc);
2611 
2612   // Initialize the run-time symbol table.
2613   SymbolTable::create_table();
2614 
2615   static_mapinfo->patch_archived_heap_embedded_pointers();
2616 
2617   // Close the mapinfo file
2618   static_mapinfo->close();
2619 
2620   static_mapinfo->unmap_region(MetaspaceShared::bm);
2621 
2622   FileMapInfo *dynamic_mapinfo = FileMapInfo::dynamic_info();
2623   if (dynamic_mapinfo != NULL) {
2624     intptr_t* buffer = (intptr_t*)dynamic_mapinfo->serialized_data();
2625     ReadClosure rc(&buffer);
2626     SymbolTable::serialize_shared_table_header(&rc, false);
2627     SystemDictionaryShared::serialize_dictionary_headers(&rc, false);
2628     dynamic_mapinfo->close();
2629   }
2630 
2631   if (PrintSharedArchiveAndExit) {
2632     if (PrintSharedDictionary) {
2633       tty->print_cr("\nShared classes:\n");
2634       SystemDictionaryShared::print_on(tty);
2635     }
2636     if (FileMapInfo::current_info() == NULL || _archive_loading_failed) {
2637       tty->print_cr("archive is invalid");
2638       vm_exit(1);
2639     } else {
2640       tty->print_cr("archive is valid");
2641       vm_exit(0);
2642     }
2643   }
2644 }
2645 
2646 // JVM/TI RedefineClasses() support:
2647 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2648   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2649 
2650   if (UseSharedSpaces) {
2651     // remap the shared readonly space to shared readwrite, private
2652     FileMapInfo* mapinfo = FileMapInfo::current_info();
2653     if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2654       return false;
2655     }
2656     if (FileMapInfo::dynamic_info() != NULL) {
2657       mapinfo = FileMapInfo::dynamic_info();
2658       if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2659         return false;
2660       }
2661     }
2662     _remapped_readwrite = true;
2663   }
2664   return true;
2665 }
2666 
2667 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2668   // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2669   // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2670   // or so.
2671   _mc_region.print_out_of_space_msg(name, needed_bytes);
2672   _rw_region.print_out_of_space_msg(name, needed_bytes);
2673   _ro_region.print_out_of_space_msg(name, needed_bytes);
2674 
2675   vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2676                                 "Please reduce the number of shared classes.");
2677 }
2678 
2679 // This is used to relocate the pointers so that the base archive can be mapped at
2680 // MetaspaceShared::requested_base_address() without runtime relocation.
2681 intx MetaspaceShared::final_delta() {
2682   return intx(MetaspaceShared::requested_base_address())  // We want the base archive to be mapped to here at runtime
2683        - intx(SharedBaseAddress);                         // .. but the base archive is mapped at here at dump time
2684 }
2685 
2686 void MetaspaceShared::print_on(outputStream* st) {
2687   if (UseSharedSpaces || DumpSharedSpaces) {
2688     st->print("CDS archive(s) mapped at: ");
2689     address base;
2690     address top;
2691     if (UseSharedSpaces) { // Runtime
2692       base = (address)MetaspaceObj::shared_metaspace_base();
2693       address static_top = (address)_shared_metaspace_static_top;
2694       top = (address)MetaspaceObj::shared_metaspace_top();
2695       st->print("[" PTR_FORMAT "-" PTR_FORMAT "-" PTR_FORMAT "), ", p2i(base), p2i(static_top), p2i(top));
2696     } else if (DumpSharedSpaces) { // Dump Time
2697       base = (address)_shared_rs.base();
2698       top = (address)_shared_rs.end();
2699       st->print("[" PTR_FORMAT "-" PTR_FORMAT "), ", p2i(base), p2i(top));
2700     }
2701     st->print("size " SIZE_FORMAT ", ", top - base);
2702     st->print("SharedBaseAddress: " PTR_FORMAT ", ArchiveRelocationMode: %d.", SharedBaseAddress, (int)ArchiveRelocationMode);
2703   } else {
2704     st->print("CDS disabled.");
2705   }
2706   st->cr();
2707 }
2708 
2709 
2710 
2711 
2712