sp::LUTSpec::ThreeValue< N > Struct Template Reference

Three-value logic integer. More...

#include <LUT.hpp>

Public Types
using	T = __uint< N >
	The type used to represent binary integers. More...

Public Attributes
T	value = 0
	The value to insert into the lookup table. More...
T	dontCare = 0
	The bits from value that are "don't care" values. More...

Static Public Attributes
static constexpr __uint< N >	AllOnes = ~(T)0
	A value with all ones. More...

Detailed Description

template<int N = 32>
struct sp::LUTSpec::ThreeValue< N >

Three-value logic integer.

Each bit in the integer may be a zero, one, or a don't care value. Don't care values are useful for reducing the size of the LUT's representation.

Member Typedef Documentation

T

template<int N = 32>

using sp::LUTSpec::ThreeValue< N >::T = __uint<N>

The type used to represent binary integers.

Member Data Documentation

AllOnes

template<int N = 32>

constexpr __uint<N> sp::LUTSpec::ThreeValue< N >::AllOnes = ~(T)0

staticconstexpr

A value with all ones.

This is particularly useful as a value for dontCare.

dontCare

template<int N = 32>

T sp::LUTSpec::ThreeValue< N >::dontCare = 0

The bits from value that are "don't care" values.

For best performance, as many bits in this field should be one as possible (while still being correct).

If a bit in this field is one, then it is not defined whether the corresponding bit in value will be returned by sp::LUT as a zero or a one. In this case, sp::LUT might not exhibit consistent behaviour (returning 0 under some circumstances, and 1 under others).

value

template<int N = 32>

T sp::LUTSpec::ThreeValue< N >::value = 0

The value to insert into the lookup table.