openjdk/src/hotspot/share/gc/z/zAllocator.cpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#include "gc/z/zAllocator.hpp"
#include "gc/z/zObjectAllocator.hpp"
#include "gc/z/zPageAge.inline.hpp"

ZAllocatorEden*          ZAllocator::_eden;
ZAllocatorForRelocation* ZAllocator::_relocation[ZAllocator::_relocation_allocators];

ZAllocator::ZAllocator(ZPageAge age)
  : _object_allocator(age) {}

void ZAllocator::retire_pages() {
  _object_allocator.retire_pages();
}

ZAllocatorEden::ZAllocatorEden()
  : ZAllocator(ZPageAge::eden) {
  ZAllocator::_eden = this;
}

size_t ZAllocatorEden::remaining() const {
  return _object_allocator.remaining();
}

ZPageAge ZAllocatorForRelocation::install() {
  for (uint i = 0; i < ZAllocator::_relocation_allocators; ++i) {
    if (_relocation[i] == nullptr) {
      _relocation[i] = this;
      return to_zpageage(i + 1);
    }
  }

  ShouldNotReachHere();
  return ZPageAge::eden;
}

ZAllocatorForRelocation::ZAllocatorForRelocation()
  : ZAllocator(install()) {}

zaddress ZAllocatorForRelocation::alloc_object(size_t size) {
  return _object_allocator.alloc_object_for_relocation(size);
}

void ZAllocatorForRelocation::undo_alloc_object(zaddress addr, size_t size) {
  _object_allocator.undo_alloc_object_for_relocation(addr, size);
}

ZPage* ZAllocatorForRelocation::alloc_page_for_relocation(ZPageType type, size_t size, ZAllocationFlags flags) {
  return _object_allocator.alloc_page_for_relocation(type, size, flags);
}