gcArguments.hpp

/*
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 * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * accompanied this code).
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#ifndef SHARE_GC_SHARED_GCARGUMENTS_HPP
#define SHARE_GC_SHARED_GCARGUMENTS_HPP

#include "memory/allocation.hpp"

class CollectedHeap;

extern size_t HeapAlignment;
extern size_t SpaceAlignment;

class GCArguments {
protected:
  // Initialize HeapAlignment, SpaceAlignment, and extra alignments (E.g. GenAlignment)
  virtual void initialize_alignments() = 0;
  virtual void initialize_heap_flags_and_sizes();
  virtual void initialize_size_info();

  DEBUG_ONLY(void assert_flags();)
  DEBUG_ONLY(void assert_size_info();)

public:
  virtual void initialize();
  virtual size_t conservative_max_heap_alignment() = 0;

  // Used by heap size heuristics to determine max
  // amount of address space to use for the heap.
  virtual size_t heap_virtual_to_physical_ratio();

  virtual CollectedHeap* create_heap() = 0;

  // Allows GCs to tell external code if it's supported or not in the current setup.
  virtual bool is_supported() const {
    return true;
  }

  void initialize_heap_sizes();

  static size_t compute_heap_alignment();
};

#endif // SHARE_GC_SHARED_GCARGUMENTS_HPP