src/hotspot/share/gc/shared/stringdedup/stringDedupConfig.hpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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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#ifndef SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPCONFIG_HPP
#define SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPCONFIG_HPP

#include "gc/shared/stringdedup/stringDedup.hpp"
#include "memory/allStatic.hpp"
#include "utilities/globalDefinitions.hpp"

// Provides access to canonicalized configuration parameter values.  This
// class captures the various StringDeduplicationXXX command line option
// values, massages them, and provides error checking support.
class StringDedup::Config : AllStatic {
  static size_t _initial_table_size;
  static int _age_threshold;
  static double _load_factor_for_growth;
  static double _load_factor_for_shrink;
  static double _load_factor_target;
  static size_t _minimum_dead_for_cleanup;
  static double _dead_factor_for_cleanup;
  static uint64_t _hash_seed;

  static const size_t good_sizes[];
  static const size_t min_good_size;
  static const size_t max_good_size;
  static size_t good_size(size_t n);

public:
  // Perform ergonomic adjustments and error checking.
  // Returns true on success, false if some error check failed.
  static bool ergo_initialize();

  static void initialize();

  static size_t initial_table_size();
  static int age_threshold();
  static uint64_t hash_seed();

  static size_t grow_threshold(size_t table_size);
  static size_t shrink_threshold(size_t table_size);
  static bool should_grow_table(size_t table_size, size_t entry_count);
  static bool should_shrink_table(size_t table_size, size_t entry_count);
  static size_t desired_table_size(size_t entry_count);
  static bool should_cleanup_table(size_t entry_count, size_t dead_count);
};

#endif // SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPCONFIG_HPP