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cached-powers.h
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27 
28 #ifndef V8_CACHED_POWERS_H_
29 #define V8_CACHED_POWERS_H_
30 
31 #include "diy-fp.h"
32 
33 namespace v8 {
34 namespace internal {
35 
37  public:
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 v8::internal
63 
64 #endif // V8_CACHED_POWERS_H_
static const int kMaxDecimalExponent
Definition: cached-powers.h:43
static const int kMinDecimalExponent
Definition: cached-powers.h:42
static const int kDecimalExponentDistance
Definition: cached-powers.h:40
static void GetCachedPowerForBinaryExponentRange(int min_exponent, int max_exponent, DiyFp *power, int *decimal_exponent)
static void GetCachedPowerForDecimalExponent(int requested_exponent, DiyFp *power, int *found_exponent)