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ECC-1930: Cleanup

This commit is contained in:
Eugen Betke 2024-10-09 08:53:15 +00:00 committed by shahramn
parent f0b40ca4d4
commit 5f5ae2056f
1 changed files with 30 additions and 40 deletions
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66
src/NumericLimits.h
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@ -11,15 +11,21 @@
#pragma once #pragma once
#include <array> #include <array>
#include <cstdint>
#include <climits> // CHAR_BIT #include <climits> // CHAR_BIT
// NumericLimits is a class template that provides the minimum and maximum values for a given number of bits. // NumericLimits is a class template that provides the minimum and maximum values for a given number of bits.
// The minimum and maximum values are calculated for both signed and unsigned integral types. // The minimum and maximum values are calculated for both signed and unsigned integral types.
template <typename ValueType, bool = std::is_signed<ValueType>::value, bool = std::is_integral<ValueType>::value>
struct NumericLimits
{
static_assert(std::is_integral<ValueType>::value, "ValueType must be an integral type");
};
// Example: // Example:
// For a 16-bit signed integer, the minimum and maximum values are: // For a 16-bit signed integer, the minimum and maximum values are:
// nbits | min | max // nBits | min | max
// ----- | --- | --- // ----- | --- | ---
// 1 | -1 | 0 // 1 | -1 | 0
// 2 | -2 | 1 // 2 | -2 | 1
@ -29,47 +35,40 @@
// 15 | -16384 | 16383 // 15 | -16384 | 16383
// 16 | -32768 | 32767 // 16 | -32768 | 32767
template <typename ValueType, bool = std::is_signed<ValueType>::value, bool = std::is_integral<ValueType>::value> template <typename ValueType>
struct NumericLimits struct NumericLimits<ValueType, true, true>
{ {
private: private:
static constexpr uint8_t MaxN = CHAR_BIT * sizeof(ValueType); static constexpr std::size_t maxNBits = CHAR_BIT * sizeof(ValueType);
static constexpr std::array<ValueType, MaxN> max_ = []() { static constexpr std::array<ValueType, maxNBits> max_ = []() {
std::array<ValueType, MaxN> max{}; std::array<ValueType, maxNBits> max{};
using UnsignedValueType = std::make_unsigned_t<ValueType>; using UnsignedValueType = std::make_unsigned_t<ValueType>;
constexpr UnsignedValueType ones = ~UnsignedValueType{ 0 }; constexpr UnsignedValueType ones = ~UnsignedValueType{ 0 };
max[0] = 0; max[0] = 0;
for (uint8_t i = 1; i < MaxN; ++i) { for (std::size_t i = 1; i < maxNBits; ++i) {
max[i] = static_cast<ValueType>(ones >> (MaxN - i)); max[i] = static_cast<ValueType>(ones >> (maxNBits - i));
} }
return max; return max;
}(); }();
static constexpr std::array<ValueType, MaxN> min_ = []() { static constexpr std::array<ValueType, maxNBits> min_ = []() {
std::array<ValueType, MaxN> min{}; std::array<ValueType, maxNBits> min{};
for (uint8_t i = 0; i < MaxN; ++i) { for (std::size_t i = 0; i < maxNBits; ++i) {
min[i] = ~max_[i]; min[i] = ~max_[i];
} }
return min; return min;
}(); }();
public: public:
static constexpr ValueType min(uint8_t nbits) static constexpr ValueType min(std::size_t nBits) { return min_[nBits - 1]; }
{ static constexpr ValueType max(std::size_t nBits) { return max_[nBits - 1]; }
return min_[nbits - 1];
}
static constexpr ValueType max(uint8_t nbits)
{
return max_[nbits - 1];
}
}; };
// Example: // Example:
// For a 16-bit unsigned integer, the minimum and maximum values are: // For a 16-bit unsigned integer, the minimum and maximum values are:
// nbits | min | max // nBits | min | max
// ----- | --- | --- // ----- | --- | ---
// 1 | 0 | 1 // 1 | 0 | 1
// 2 | 0 | 3 // 2 | 0 | 3
@ -82,29 +81,20 @@ public:
template <typename ValueType> template <typename ValueType>
struct NumericLimits<ValueType, false, true> struct NumericLimits<ValueType, false, true>
{ {
static_assert(std::is_integral<ValueType>::value, "ValueType must be an integral type");
private: private:
static constexpr uint8_t MaxN = CHAR_BIT * sizeof(ValueType); static constexpr std::size_t maxNBits = CHAR_BIT * sizeof(ValueType);
static constexpr std::array<ValueType, MaxN> max_ = []() { static constexpr std::array<ValueType, maxNBits> max_ = []() {
std::array<ValueType, MaxN> max{}; std::array<ValueType, maxNBits> max{};
constexpr ValueType ones = ~(static_cast<ValueType>(0)); constexpr ValueType ones = ~(static_cast<ValueType>(0));
max[0] = 1; max[0] = 1;
for (uint8_t i = 1; i < MaxN; ++i) { for (std::size_t i = 1; i < maxNBits; ++i) {
max[i] = ones >> (MaxN - i - 1); max[i] = ones >> (maxNBits - i - 1);
} }
return max; return max;
}(); }();
public: public:
static constexpr ValueType min(uint8_t nbits) static constexpr ValueType min(std::size_t nBits) { return 0; }
{ static constexpr ValueType max(std::size_t nBits) { return max_[nBits - 1]; }
return 0;
}
static constexpr ValueType max(uint8_t nbits)
{
return max_[nbits - 1];
}
}; };