2022-06-26 11:58:44 +00:00
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// -*- c++ -*-
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2022-06-26 10:41:55 +00:00
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#ifndef DOUBLE_CONVERSION_CACHED_POWERS_H_
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#define DOUBLE_CONVERSION_CACHED_POWERS_H_
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#include "third_party/double-conversion/diy-fp.h"
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namespace double_conversion {
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namespace PowersOfTenCache {
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// Not all powers of ten are cached. The decimal exponent of two neighboring
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// cached numbers will differ by kDecimalExponentDistance.
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static const int kDecimalExponentDistance = 8;
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static const int kMinDecimalExponent = -348;
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static const int kMaxDecimalExponent = 340;
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// Returns a cached power-of-ten with a binary exponent in the range
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// [min_exponent; max_exponent] (boundaries included).
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void GetCachedPowerForBinaryExponentRange(int min_exponent,
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int max_exponent,
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DiyFp* power,
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int* decimal_exponent);
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// Returns a cached power of ten x ~= 10^k such that
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// k <= decimal_exponent < k + kCachedPowersDecimalDistance.
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// The given decimal_exponent must satisfy
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// kMinDecimalExponent <= requested_exponent, and
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// requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance.
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void GetCachedPowerForDecimalExponent(int requested_exponent,
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DiyFp* power,
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int* found_exponent);
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} // namespace PowersOfTenCache
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} // namespace double_conversion
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#endif // DOUBLE_CONVERSION_CACHED_POWERS_H_
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