text: // Copyright 2017 Polonite Authors. All rights reserved.
  // Copyright 2010 the V8 project authors. All rights reserved.
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  //       notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  //       copyright notice, this list of conditions and the following
  //       disclaimer in the documentation and/or other materials provided
  //       with the distribution.
  //     * Neither the name of Google Inc. nor the names of its
  //       contributors may be used to endorse or promote products derived
  //       from this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #ifndef STP_BASE_DTOA_CACHEDPOWERS_H_
  #define STP_BASE_DTOA_CACHEDPOWERS_H_
  
  #include "Base/Dtoa/DiyFp.h"
  
  namespace stp {
  
  namespace dtoa {
  
  class PowersOfTenCache {
   public:
    // Not all powers of ten are cached. The decimal exponent of two neighboring
    // cached numbers will differ by DecimalExponentDistance.
    static const int DecimalExponentDistance;
  
    static const int MinDecimalExponent;
    static const int MaxDecimalExponent;
  
    // Returns a cached power-of-ten with a binary exponent in the range
    // [min_exponent; max_exponent] (boundaries included).
    static void GetCachedPowerForBinaryExponentRange(int min_exponent,
                                                     int max_exponent,
                                                     DiyFp* power,
                                                     int* decimal_exponent);
  
    // Returns a cached power of ten x ~= 10^k such that
    //   k <= decimal_exponent < k + CachedPowersDecimalDistance.
    // The given decimal_exponent must satisfy
    //   MinDecimalExponent <= requested_exponent, and
    //   requested_exponent < MaxDecimalExponent + DecimalExponentDistance.
    static void GetCachedPowerForDecimalExponent(int requested_exponent,
                                                 DiyFp* power,
                                                 int* found_exponent);
  };
  } // namespace dtoa
  
  } // namespace stp
  
  #endif // STP_BASE_DTOA_CACHEDPOWERS_H_
  