Gray::cBits Struct Reference

#include <cBits.h>

Inheritance diagram for Gray::cBits:

Static Public Member Functions
static constexpr size_t	GetSizeBytes (BIT_ENUM_t nBits) noexcept
template<typename TYPE >
static constexpr TYPE	Mask1 (BIT_ENUM_t nBit) noexcept
template<typename TYPE >
static constexpr bool	IsMask1 (TYPE nVal) noexcept
template<typename TYPE >
static constexpr bool	IsSet (TYPE nVal, BIT_ENUM_t nBit) noexcept
template<typename TYPE >
static constexpr bool	IsClear (TYPE nVal, BIT_ENUM_t nBit) noexcept
template<typename TYPE >
static constexpr TYPE	SetBit (TYPE nVal, BIT_ENUM_t nBit) noexcept
template<typename TYPE >
static constexpr TYPE	ClearBit (TYPE nVal, BIT_ENUM_t nBit) noexcept
template<typename TYPE >
static constexpr bool	HasMask (TYPE nVal, TYPE nMask) noexcept
template<typename TYPE >
static BIT_ENUM_t	Highest1Bit (TYPE nMask) noexcept
template<typename TYPE >
static BIT_ENUM_t	Count1Bits (TYPE nMask) noexcept
template<typename TYPE >
static TYPE	Rotl (TYPE nVal, BIT_ENUM_t nBits) noexcept
template<typename TYPE >
static TYPE	Rotr (TYPE nVal, BIT_ENUM_t nBits) noexcept
template<typename TYPE >
static TYPE	Reverse (TYPE nVal) noexcept
template<>
BIT_ENUM_t	Count1Bits (UINT32 nVal) noexcept
template<>
BYTE	Reverse (BYTE nVal) noexcept
template<>
UINT32	Reverse (UINT32 nVal) noexcept
template<>
ULONG	Reverse (ULONG nVal) noexcept

Static Public Attributes
static const BYTE	k_8 = 8
	represent the 8 bits in a byte. BIT_ENUM_t More...

Friends
class	cBitsTests

Detailed Description

Bit mask type operations of all sorts. on various integral data types.

Member Function Documentation

ClearBit()

template<typename TYPE >

static constexpr TYPE Gray::cBits::ClearBit ( TYPE  nVal, BIT_ENUM_t  nBit  )

inlinestaticconstexprnoexcept

Count1Bits() [1/2]

template<typename TYPE >

static BIT_ENUM_t Gray::cBits::Count1Bits ( TYPE  nMask )

inlinestaticnoexcept

Count total number of 1 bits. like: __builtin_popcount()

Count1Bits() [2/2]

template<>

BIT_ENUM_t Gray::cBits::Count1Bits ( UINT32  nVal )

inlinestaticnoexcept

A math trick for counting 1 bits in 32 bit numbers.

GetSizeBytes()

static constexpr size_t Gray::cBits::GetSizeBytes ( BIT_ENUM_t  nBits )

inlinestaticconstexprnoexcept

How many bytes to hold these bits. Round up to next byte.

HasMask()

template<typename TYPE >

static constexpr bool Gray::cBits::HasMask ( TYPE  nVal, TYPE  nMask  )

inlinestaticconstexprnoexcept

Any nMask bits set ?

Highest1Bit()

template<typename TYPE >

static BIT_ENUM_t Gray::cBits::Highest1Bit ( TYPE  nMask )

inlinestaticnoexcept

What is the highest set bit in this primitive TYPE. 1 based. MSB.

Returns

1 for value of 1. 0 = no bits. e.g. nMask=8 return=4 similar to ffs() (POSIX) or builtin_clz(), __builtin_clzll (__GNUC) ? similar to _BitScanReverse, _BitScanReverse64. https://msdn.microsoft.com/en-us/library/fbxyd7zd.aspx x86 has BSR instruction. PowerPC there's a similar cntlz ("count leading zeros") instruction.

IsClear()

template<typename TYPE >

static constexpr bool Gray::cBits::IsClear ( TYPE  nVal, BIT_ENUM_t  nBit  )

inlinestaticconstexprnoexcept

Test if a bit is NOT set.

IsMask1()

template<typename TYPE >

static constexpr bool Gray::cBits::IsMask1 ( TYPE  nVal )

inlinestaticconstexprnoexcept

Does this just have a single bit on ? Is power of 2 ?

IsSet()

template<typename TYPE >

static constexpr bool Gray::cBits::IsSet ( TYPE  nVal, BIT_ENUM_t  nBit  )

inlinestaticconstexprnoexcept

Test if a bit is set.

Mask1()

template<typename TYPE >

static constexpr TYPE Gray::cBits::Mask1 ( BIT_ENUM_t  nBit )

inlinestaticconstexprnoexcept

Create a 1 bit mask of a given TYPE. Overflow/Underflow is just lost. _1BITMASK(nBit) = cBits::Mask1<size_t>(nBit). default TYPE = size_t

Reverse() [1/4]

template<>

BYTE Gray::cBits::Reverse ( BYTE  nVal )

inlinestaticnoexcept

Reverse the order of the 8 bits. using 32 or 64 bit temporary. http://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith32Bits

Reverse() [2/4]

template<typename TYPE >

static TYPE Gray::cBits::Reverse ( TYPE  nVal )

inlinestaticnoexcept

Reverse the order of the bits. ASSUME not signed?

Reverse() [3/4]

template<>

UINT32 Gray::cBits::Reverse ( UINT32  nVal )

inlinestaticnoexcept

Reverse the order of the 32 bits.

Reverse() [4/4]

template<>

ULONG Gray::cBits::Reverse ( ULONG  nVal )

inlinestaticnoexcept

ULONG may be equiv to UINT32 or UINT64

Rotl()

template<typename TYPE >

static TYPE Gray::cBits::Rotl ( TYPE  nVal, BIT_ENUM_t  nBits  )

inlinestaticnoexcept

Rotate bits left. If system doesn't have an inline rotate left function for X bits.

Rotr()

template<typename TYPE >

static TYPE Gray::cBits::Rotr ( TYPE  nVal, BIT_ENUM_t  nBits  )

inlinestaticnoexcept

Rotate bits right.

SetBit()

template<typename TYPE >

static constexpr TYPE Gray::cBits::SetBit ( TYPE  nVal, BIT_ENUM_t  nBit  )

inlinestaticconstexprnoexcept

Friends And Related Function Documentation

cBitsTests

friend class cBitsTests

friend

Member Data Documentation

k_8

const BYTE Gray::cBits::k_8 = 8

static

represent the 8 bits in a byte. BIT_ENUM_t

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The documentation for this struct was generated from the following file:

• c:/Dennis/Source/Gray/GrayCore/include/cBits.h