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27
28#ifndef DOUBLE_CONVERSION_CACHED_POWERS_H_
29#define DOUBLE_CONVERSION_CACHED_POWERS_H_
30
31#include "diy-fp.h"
32
33namespace double_conversion {
34
35class PowersOfTenCache {
36 public:
37
38 // Not all powers of ten are cached. The decimal exponent of two neighboring
39 // cached numbers will differ by kDecimalExponentDistance.
40 static const int kDecimalExponentDistance;
41
42 static const int kMinDecimalExponent;
43 static const int kMaxDecimalExponent;
44
45 // Returns a cached power-of-ten with a binary exponent in the range
46 // [min_exponent; max_exponent] (boundaries included).
47 static void GetCachedPowerForBinaryExponentRange(int min_exponent,
48 int max_exponent,
49 DiyFp* power,
50 int* decimal_exponent);
51
52 // Returns a cached power of ten x ~= 10^k such that
53 // k <= decimal_exponent < k + kCachedPowersDecimalDistance.
54 // The given decimal_exponent must satisfy
55 // kMinDecimalExponent <= requested_exponent, and
56 // requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance.
57 static void GetCachedPowerForDecimalExponent(int requested_exponent,
58 DiyFp* power,
59 int* found_exponent);
60};
61
62} // namespace double_conversion
63
64#endif // DOUBLE_CONVERSION_CACHED_POWERS_H_
65