// The maximum byte sizes are for the initial layout of the
// virtual spaces and are not the limit on the maximum bytes sizes.

void AdjoiningVirtualSpaces::initialize(size_t max_low_byte_size,
                                        size_t init_low_byte_size,
                                        size_t init_high_byte_size) {

  {- -------------------------------------------
  (1) 各世代に対応する ReservedSpace を取得する.
      ---------------------------------------- -}

      // The reserved spaces for the two parts of the virtual space.
      ReservedSpace old_rs   = _reserved_space.first_part(max_low_byte_size);
      ReservedSpace young_rs = _reserved_space.last_part(max_low_byte_size);

  {- -------------------------------------------
  (1) 取得した ReservedSpace を元に 
      PSVirtualSpace オブジェクトと PSVirtualSpaceHighToLow オブジェクトを作成し, 
      それぞれ PSVirtualSpace::expand_by() と PSVirtualSpaceHighToLow::expand_by() で
      初期サイズ分の仮想メモリ空間を commit する.

      expand_by() が失敗したら, ここで異常終了.
      ---------------------------------------- -}

      _low = new PSVirtualSpace(old_rs, alignment());
      if (!_low->expand_by(init_low_byte_size)) {
        vm_exit_during_initialization("Could not reserve enough space for "
                                      "object heap");
      }

      _high = new PSVirtualSpaceHighToLow(young_rs, alignment());
      if (!_high->expand_by(init_high_byte_size)) {
        vm_exit_during_initialization("Could not reserve enough space for "
                                      "object heap");
      }
    }