src/hotspot/share/cds/archiveUtils.cpp

/*
 * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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#include "precompiled.hpp"
#include "cds/archiveBuilder.hpp"
#include "cds/archiveHeapLoader.inline.hpp"
#include "cds/archiveUtils.hpp"
#include "cds/classListParser.hpp"
#include "cds/classListWriter.hpp"
#include "cds/dynamicArchive.hpp"
#include "cds/filemap.hpp"
#include "cds/heapShared.hpp"
#include "cds/metaspaceShared.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/vmClasses.hpp"
#include "interpreter/bootstrapInfo.hpp"
#include "memory/metaspaceUtils.hpp"
#include "memory/resourceArea.hpp"
#include "oops/compressedOops.inline.hpp"
#include "runtime/arguments.hpp"
#include "utilities/bitMap.inline.hpp"
#include "utilities/debug.hpp"
#include "utilities/formatBuffer.hpp"
#include "utilities/globalDefinitions.hpp"

CHeapBitMap* ArchivePtrMarker::_ptrmap = nullptr;
VirtualSpace* ArchivePtrMarker::_vs;

bool ArchivePtrMarker::_compacted;

void ArchivePtrMarker::initialize(CHeapBitMap* ptrmap, VirtualSpace* vs) {
  assert(_ptrmap == nullptr, "initialize only once");
  _vs = vs;
  _compacted = false;
  _ptrmap = ptrmap;

  // Use this as initial guesstimate. We should need less space in the
  // archive, but if we're wrong the bitmap will be expanded automatically.
  size_t estimated_archive_size = MetaspaceGC::capacity_until_GC();
  // But set it smaller in debug builds so we always test the expansion code.
  // (Default archive is about 12MB).
  DEBUG_ONLY(estimated_archive_size = 6 * M);

  // We need one bit per pointer in the archive.
  _ptrmap->initialize(estimated_archive_size / sizeof(intptr_t));
}

void ArchivePtrMarker::mark_pointer(address* ptr_loc) {
  assert(_ptrmap != nullptr, "not initialized");
  assert(!_compacted, "cannot mark anymore");

  if (ptr_base() <= ptr_loc && ptr_loc < ptr_end()) {
    address value = *ptr_loc;
    // We don't want any pointer that points to very bottom of the archive, otherwise when
    // MetaspaceShared::default_base_address()==0, we can't distinguish between a pointer
    // to nothing (null) vs a pointer to an objects that happens to be at the very bottom
    // of the archive.
    assert(value != (address)ptr_base(), "don't point to the bottom of the archive");

    if (value != nullptr) {
      assert(uintx(ptr_loc) % sizeof(intptr_t) == 0, "pointers must be stored in aligned addresses");
      size_t idx = ptr_loc - ptr_base();
      if (_ptrmap->size() <= idx) {
        _ptrmap->resize((idx + 1) * 2);
      }
      assert(idx < _ptrmap->size(), "must be");
      _ptrmap->set_bit(idx);
      //tty->print_cr("Marking pointer [" PTR_FORMAT "] -> " PTR_FORMAT " @ " SIZE_FORMAT_W(5), p2i(ptr_loc), p2i(*ptr_loc), idx);
    }
  }
}

void ArchivePtrMarker::clear_pointer(address* ptr_loc) {
  assert(_ptrmap != nullptr, "not initialized");
  assert(!_compacted, "cannot clear anymore");

  assert(ptr_base() <= ptr_loc && ptr_loc < ptr_end(), "must be");
  assert(uintx(ptr_loc) % sizeof(intptr_t) == 0, "pointers must be stored in aligned addresses");
  size_t idx = ptr_loc - ptr_base();
  assert(idx < _ptrmap->size(), "cannot clear pointers that have not been marked");
  _ptrmap->clear_bit(idx);
  //tty->print_cr("Clearing pointer [" PTR_FORMAT "] -> " PTR_FORMAT " @ " SIZE_FORMAT_W(5), p2i(ptr_loc), p2i(*ptr_loc), idx);
}

class ArchivePtrBitmapCleaner: public BitMapClosure {
  CHeapBitMap* _ptrmap;
  address* _ptr_base;
  address  _relocatable_base;
  address  _relocatable_end;
  size_t   _max_non_null_offset;

public:
  ArchivePtrBitmapCleaner(CHeapBitMap* ptrmap, address* ptr_base, address relocatable_base, address relocatable_end) :
    _ptrmap(ptrmap), _ptr_base(ptr_base),
    _relocatable_base(relocatable_base), _relocatable_end(relocatable_end), _max_non_null_offset(0) {}

  bool do_bit(size_t offset) {
    address* ptr_loc = _ptr_base + offset;
    address  ptr_value = *ptr_loc;
    if (ptr_value != nullptr) {
      assert(_relocatable_base <= ptr_value && ptr_value < _relocatable_end, "do not point to arbitrary locations!");
      if (_max_non_null_offset < offset) {
        _max_non_null_offset = offset;
      }
    } else {
      _ptrmap->clear_bit(offset);
      DEBUG_ONLY(log_trace(cds, reloc)("Clearing pointer [" PTR_FORMAT  "] -> null @ " SIZE_FORMAT_W(9), p2i(ptr_loc), offset));
    }

    return true;
  }

  size_t max_non_null_offset() const { return _max_non_null_offset; }
};

void ArchivePtrMarker::compact(address relocatable_base, address relocatable_end) {
  assert(!_compacted, "cannot compact again");
  ArchivePtrBitmapCleaner cleaner(_ptrmap, ptr_base(), relocatable_base, relocatable_end);
  _ptrmap->iterate(&cleaner);
  compact(cleaner.max_non_null_offset());
}

void ArchivePtrMarker::compact(size_t max_non_null_offset) {
  assert(!_compacted, "cannot compact again");
  _ptrmap->resize(max_non_null_offset + 1);
  _compacted = true;
}

char* DumpRegion::expand_top_to(char* newtop) {
  assert(is_allocatable(), "must be initialized and not packed");
  assert(newtop >= _top, "must not grow backwards");
  if (newtop > _end) {
    ArchiveBuilder::current()->report_out_of_space(_name, newtop - _top);
    ShouldNotReachHere();
  }

  commit_to(newtop);
  _top = newtop;

  if (_max_delta > 0) {
    uintx delta = ArchiveBuilder::current()->buffer_to_offset((address)(newtop-1));
    if (delta > _max_delta) {
      // This is just a sanity check and should not appear in any real world usage. This
      // happens only if you allocate more than 2GB of shared objects and would require
      // millions of shared classes.
      log_error(cds)("Out of memory in the CDS archive: Please reduce the number of shared classes.");
      MetaspaceShared::unrecoverable_writing_error();
    }
  }

  return _top;
}

void DumpRegion::commit_to(char* newtop) {
  Arguments::assert_is_dumping_archive();
  char* base = _rs->base();
  size_t need_committed_size = newtop - base;
  size_t has_committed_size = _vs->committed_size();
  if (need_committed_size < has_committed_size) {
    return;
  }

  size_t min_bytes = need_committed_size - has_committed_size;
  size_t preferred_bytes = 1 * M;
  size_t uncommitted = _vs->reserved_size() - has_committed_size;

  size_t commit = MAX2(min_bytes, preferred_bytes);
  commit = MIN2(commit, uncommitted);
  assert(commit <= uncommitted, "sanity");

  if (!_vs->expand_by(commit, false)) {
    log_error(cds)("Failed to expand shared space to " SIZE_FORMAT " bytes",
                    need_committed_size);
    MetaspaceShared::unrecoverable_writing_error();
  }

  const char* which;
  if (_rs->base() == (char*)MetaspaceShared::symbol_rs_base()) {
    which = "symbol";
  } else {
    which = "shared";
  }
  log_debug(cds)("Expanding %s spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9)  " bytes ending at %p]",
                 which, commit, _vs->actual_committed_size(), _vs->high());
}


char* DumpRegion::allocate(size_t num_bytes) {
  char* p = (char*)align_up(_top, (size_t)SharedSpaceObjectAlignment);
  char* newtop = p + align_up(num_bytes, (size_t)SharedSpaceObjectAlignment);
  expand_top_to(newtop);
  memset(p, 0, newtop - p);
  return p;
}

void DumpRegion::append_intptr_t(intptr_t n, bool need_to_mark) {
  assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
  intptr_t *p = (intptr_t*)_top;
  char* newtop = _top + sizeof(intptr_t);
  expand_top_to(newtop);
  *p = n;
  if (need_to_mark) {
    ArchivePtrMarker::mark_pointer(p);
  }
}

void DumpRegion::print(size_t total_bytes) const {
  log_debug(cds)("%s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,
                 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()),
                 p2i(ArchiveBuilder::current()->to_requested(_base)));
}

void DumpRegion::print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
  log_error(cds)("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
                 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
  if (strcmp(_name, failing_region) == 0) {
    log_error(cds)(" required = %d", int(needed_bytes));
  }
}

void DumpRegion::init(ReservedSpace* rs, VirtualSpace* vs) {
  _rs = rs;
  _vs = vs;
  // Start with 0 committed bytes. The memory will be committed as needed.
  if (!_vs->initialize(*_rs, 0)) {
    fatal("Unable to allocate memory for shared space");
  }
  _base = _top = _rs->base();
  _end = _rs->end();
}

void DumpRegion::pack(DumpRegion* next) {
  assert(!is_packed(), "sanity");
  _end = (char*)align_up(_top, MetaspaceShared::core_region_alignment());
  _is_packed = true;
  if (next != nullptr) {
    next->_rs = _rs;
    next->_vs = _vs;
    next->_base = next->_top = this->_end;
    next->_end = _rs->end();
  }
}

void WriteClosure::do_ptr(void** p) {
  // Write ptr into the archive; ptr can be:
  //   (a) null                 -> written as 0
  //   (b) a "buffered" address -> written as is
  //   (c) a "source"   address -> convert to "buffered" and write
  // The common case is (c). E.g., when writing the vmClasses into the archive.
  // We have (b) only when we don't have a corresponding source object. E.g.,
  // the archived c++ vtable entries.
  address ptr = *(address*)p;
  if (ptr != nullptr && !ArchiveBuilder::current()->is_in_buffer_space(ptr)) {
    ptr = ArchiveBuilder::current()->get_buffered_addr(ptr);
  }
  _dump_region->append_intptr_t((intptr_t)ptr, true);
}

void WriteClosure::do_oop(oop* o) {
  if (*o == nullptr) {
    _dump_region->append_intptr_t(0);
  } else {
    assert(HeapShared::can_write(), "sanity");
    intptr_t p;
    if (UseCompressedOops) {
      p = (intptr_t)CompressedOops::encode_not_null(*o);
    } else {
      p = cast_from_oop<intptr_t>(HeapShared::to_requested_address(*o));
    }
    _dump_region->append_intptr_t(p);
  }
}

void WriteClosure::do_region(u_char* start, size_t size) {
  assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
  assert(size % sizeof(intptr_t) == 0, "bad size");
  do_tag((int)size);
  while (size > 0) {
    do_ptr((void**)start);
    start += sizeof(intptr_t);
    size -= sizeof(intptr_t);
  }
}

void ReadClosure::do_ptr(void** p) {
  assert(*p == nullptr, "initializing previous initialized pointer.");
  intptr_t obj = nextPtr();
  assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
         "hit tag while initializing ptrs.");
  *p = (void*)obj;
}

void ReadClosure::do_u4(u4* p) {
  intptr_t obj = nextPtr();
  *p = (u4)(uintx(obj));
}

void ReadClosure::do_int(int* p) {
  intptr_t obj = nextPtr();
  *p = (int)(intx(obj));
}

void ReadClosure::do_bool(bool* p) {
  intptr_t obj = nextPtr();
  *p = (bool)(uintx(obj));
}

void ReadClosure::do_tag(int tag) {
  int old_tag;
  old_tag = (int)(intptr_t)nextPtr();
  // do_int(&old_tag);
  assert(tag == old_tag, "old tag doesn't match");
  FileMapInfo::assert_mark(tag == old_tag);
}

void ReadClosure::do_oop(oop *p) {
  if (UseCompressedOops) {
    narrowOop o = CompressedOops::narrow_oop_cast(nextPtr());
    if (CompressedOops::is_null(o) || !ArchiveHeapLoader::is_in_use()) {
      *p = nullptr;
    } else {
      assert(ArchiveHeapLoader::can_use(), "sanity");
      assert(ArchiveHeapLoader::is_in_use(), "must be");
      *p = ArchiveHeapLoader::decode_from_archive(o);
    }
  } else {
    intptr_t dumptime_oop = nextPtr();
    if (dumptime_oop == 0 || !ArchiveHeapLoader::is_in_use()) {
      *p = nullptr;
    } else {
      assert(!ArchiveHeapLoader::is_loaded(), "ArchiveHeapLoader::can_load() is not supported for uncompessed oops");
      intptr_t runtime_oop = dumptime_oop + ArchiveHeapLoader::mapped_heap_delta();
      *p = cast_to_oop(runtime_oop);
    }
  }
}

void ReadClosure::do_region(u_char* start, size_t size) {
  assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
  assert(size % sizeof(intptr_t) == 0, "bad size");
  do_tag((int)size);
  while (size > 0) {
    *(intptr_t*)start = nextPtr();
    start += sizeof(intptr_t);
    size -= sizeof(intptr_t);
  }
}

void ArchiveUtils::log_to_classlist(BootstrapInfo* bootstrap_specifier, TRAPS) {
  if (ClassListWriter::is_enabled()) {
    if (SystemDictionaryShared::is_supported_invokedynamic(bootstrap_specifier)) {
      const constantPoolHandle& pool = bootstrap_specifier->pool();
      if (SystemDictionaryShared::is_builtin_loader(pool->pool_holder()->class_loader_data())) {
        // Currently lambda proxy classes are supported only for the built-in loaders.
        ResourceMark rm(THREAD);
        int pool_index = bootstrap_specifier->bss_index();
        ClassListWriter w;
        w.stream()->print("%s %s", LAMBDA_PROXY_TAG, pool->pool_holder()->name()->as_C_string());
        CDSIndyInfo cii;
        ClassListParser::populate_cds_indy_info(pool, pool_index, &cii, CHECK);
        GrowableArray<const char*>* indy_items = cii.items();
        for (int i = 0; i < indy_items->length(); i++) {
          w.stream()->print(" %s", indy_items->at(i));
        }
        w.stream()->cr();
      }
    }
  }
}