Vc  1.3.2-dev
SIMD Vector Classes for C++
const.h
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27 
28 #ifndef VC_COMMON_CONST_H_
29 #define VC_COMMON_CONST_H_
30 
31 #include <type_traits>
32 #include <Vc/global.h>
33 
34 namespace Vc_VERSIONED_NAMESPACE
35 {
36 namespace Detail
37 {
38 
39 template <int exponent> constexpr double exponentToFloat(std::integral_constant<bool, true>);
40 template <int exponent> constexpr double exponentToFloat(std::integral_constant<bool, false>);
41 template <> constexpr double exponentToFloat<0>(std::integral_constant<bool, true>)
42 {
43  return 1.;
44 }
45 template <> constexpr double exponentToFloat<0>(std::integral_constant<bool, false>)
46 {
47  return 1.;
48 }
49 template <> constexpr double exponentToFloat<-32>(std::integral_constant<bool, true>)
50 {
51  return 1. / (65536. * 65536.);
52 }
53 template <> constexpr double exponentToFloat<32>(std::integral_constant<bool, false>)
54 {
55  return 65536. * 65536.;
56 }
57 template <> constexpr double exponentToFloat<-64>(std::integral_constant<bool, true>)
58 {
59  return 1. / (65536. * 65536. * 65536. * 65536.);
60 }
61 template <> constexpr double exponentToFloat<64>(std::integral_constant<bool, false>)
62 {
63  return 65536. * 65536. * 65536. * 65536.;
64 }
65 template <int exponent>
66 constexpr double exponentToFloat(std::integral_constant<bool, false> negative)
67 {
68  return exponentToFloat<exponent - 1>(negative) * 2.0;
69 }
70 template <int exponent>
71 constexpr double exponentToFloat(std::integral_constant<bool, true> negative)
72 {
73  return exponentToFloat<exponent + 1>(negative) * 0.5;
74 }
75 template <int sign, unsigned long long mantissa, int exponent> constexpr double doubleConstant()
76 {
77  return (static_cast<double>((mantissa & 0x000fffffffffffffull) | 0x0010000000000000ull) /
78  0x0010000000000000ull) *
79  exponentToFloat<exponent>(std::integral_constant<bool, (exponent < 0)>()) * sign;
80 }
81 template <int sign, unsigned int mantissa, int exponent> constexpr float floatConstant()
82 {
83  return (static_cast<float>((mantissa & 0x007fffffu) | 0x00800000u) / 0x00800000u) *
84  static_cast<float>(
85  exponentToFloat<exponent>(std::integral_constant<bool, (exponent < 0)>())) *
86  sign;
87 }
88 
89 } // namespace Detail
90 } // namespace Vc
91 
92 #endif // VC_COMMON_CONST_H_
SimdArray< T, N, V, M > exponent(const SimdArray< T, N, V, M > &x)
Applies the std:: exponent function component-wise and concurrently.
Definition: simdarray.h:1691