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27
28#ifndef DOUBLE_CONVERSION_CACHED_POWERS_H_
29#define DOUBLE_CONVERSION_CACHED_POWERS_H_
30
31#include <wtf/dtoa/diy-fp.h>
32
33namespace WTF {
34namespace double_conversion {
35
36class PowersOfTenCache {
37 public:
38
39 // Not all powers of ten are cached. The decimal exponent of two neighboring
40 // cached numbers will differ by kDecimalExponentDistance.
41 static const int kDecimalExponentDistance;
42
43 static const int kMinDecimalExponent;
44 static const int kMaxDecimalExponent;
45
46 // Returns a cached power-of-ten with a binary exponent in the range
47 // [min_exponent; max_exponent] (boundaries included).
48 static void GetCachedPowerForBinaryExponentRange(int min_exponent,
49 int max_exponent,
50 DiyFp* power,
51 int* decimal_exponent);
52
53 // Returns a cached power of ten x ~= 10^k such that
54 // k <= decimal_exponent < k + kCachedPowersDecimalDistance.
55 // The given decimal_exponent must satisfy
56 // kMinDecimalExponent <= requested_exponent, and
57 // requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance.
58 static void GetCachedPowerForDecimalExponent(int requested_exponent,
59 DiyFp* power,
60 int* found_exponent);
61};
62
63} // namespace double_conversion
64} // namespace WTF
65
66#endif // DOUBLE_CONVERSION_CACHED_POWERS_H_
67