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

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

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 * published by the Free Software Foundation.

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 * 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.

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AdjoiningVirtualSpaces::AdjoiningVirtualSpaces(ReservedSpace rs,

                                               size_t min_low_byte_size,

                                               size_t min_high_byte_size,

                                               size_t alignment) :

  _reserved_space(rs), _min_low_byte_size(min_low_byte_size),

  _min_high_byte_size(min_high_byte_size), _low(0), _high(0),

  _alignment(alignment) {}

// 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) {

  // 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);

  _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");

  }

}

bool AdjoiningVirtualSpaces::adjust_boundary_up(size_t change_in_bytes) {

  assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

  size_t actual_change = low()->expand_into(high(), change_in_bytes);

  return actual_change != 0;

}

bool AdjoiningVirtualSpaces::adjust_boundary_down(size_t change_in_bytes) {

  assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

  size_t actual_change = high()->expand_into(low(), change_in_bytes);

  return actual_change != 0;

}