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// 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
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//
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#ifndef DOUBLE_CONVERSION_CACHED_POWERS_H_
#define DOUBLE_CONVERSION_CACHED_POWERS_H_
#include "diy-fp.h"
namespace double_conversion {
namespace PowersOfTenCache {
// Not all powers of ten are cached. The decimal exponent of two neighboring
// cached numbers will differ by kDecimalExponentDistance.
static const int kDecimalExponentDistance = 8;
static const int kMinDecimalExponent = -348;
static const int kMaxDecimalExponent = 340;
// Returns a cached power-of-ten with a binary exponent in the range
// [min_exponent; max_exponent] (boundaries included).
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 + kCachedPowersDecimalDistance.
// The given decimal_exponent must satisfy
// kMinDecimalExponent <= requested_exponent, and
// requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance.
void GetCachedPowerForDecimalExponent(int requested_exponent,
DiyFp* power,
int* found_exponent);
} // namespace PowersOfTenCache
} // namespace double_conversion
#endif // DOUBLE_CONVERSION_CACHED_POWERS_H_