LLVM: llvm::bitfields_details::BitPatterns< T, Bits > Struct Template Reference

LLVM 20.0.0git

A struct defining useful bit patterns for n-bits integer types. More...

#include "llvm/ADT/Bitfields.h"

Public Types
using	Unsigned = std::make_unsigned_t< T >
	Bit patterns are forged using the equivalent `Unsigned` type because of undefined operations over signed types (e.g.

Static Public Attributes
static constexpr unsigned	TypeBits = sizeof(Unsigned) * CHAR_BIT

static constexpr Unsigned	AllZeros = Unsigned(0)
	e.g. with TypeBits == 8 and Bits == 6.

static constexpr Unsigned	AllOnes = ~Unsigned(0)

static constexpr Unsigned	Umin = AllZeros

static constexpr Unsigned	Umax = AllOnes >> (TypeBits - Bits)

static constexpr Unsigned	SignBitMask = Unsigned(1) << (Bits - 1)

static constexpr Unsigned	Smax = Umax >> 1U

static constexpr Unsigned	Smin = ~Smax

static constexpr Unsigned	SignExtend = Unsigned(Smin << 1U)

Detailed Description

template<typename T, unsigned Bits>
struct llvm::bitfields_details::BitPatterns< T, Bits >

A struct defining useful bit patterns for n-bits integer types.

Definition at line 94 of file Bitfields.h.

Member Typedef Documentation

◆ Unsigned

template<typename T , unsigned Bits>

using llvm::bitfields_details::BitPatterns< T, Bits >::Unsigned = std::make_unsigned_t<T>

Bit patterns are forged using the equivalent Unsigned type because of undefined operations over signed types (e.g.

Bitwise shift operators). Moreover same size casting from unsigned to signed is well defined but not the other way around.

Definition at line 99 of file Bitfields.h.

Member Data Documentation

◆ AllOnes

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::AllOnes = ~Unsigned(0)

staticconstexpr

Definition at line 107 of file Bitfields.h.

◆ AllZeros

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::AllZeros = Unsigned(0)

staticconstexpr

e.g. with TypeBits == 8 and Bits == 6.

Definition at line 106 of file Bitfields.h.

◆ SignBitMask

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::SignBitMask = Unsigned(1) << (Bits - 1)

staticconstexpr

Definition at line 110 of file Bitfields.h.

Referenced by llvm::bitfields_details::Compressor< T, Bits, false >::unpack().

◆ SignExtend

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::SignExtend = Unsigned(Smin << 1U)

staticconstexpr

Definition at line 113 of file Bitfields.h.

Referenced by llvm::bitfields_details::Compressor< T, Bits, false >::unpack().

◆ Smax

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::Smax = Umax >> 1U

staticconstexpr

Definition at line 111 of file Bitfields.h.

Referenced by llvm::bitfields_details::Compressor< T, Bits, false >::pack().

◆ Smin

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::Smin = ~Smax

staticconstexpr

Definition at line 112 of file Bitfields.h.

Referenced by llvm::bitfields_details::Compressor< T, Bits, false >::pack().

◆ TypeBits

template<typename T , unsigned Bits>

constexpr unsigned llvm::bitfields_details::BitPatterns< T, Bits >::TypeBits = sizeof(Unsigned) * CHAR_BIT

staticconstexpr

Definition at line 102 of file Bitfields.h.

◆ Umax

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::Umax = AllOnes >> (TypeBits - Bits)

staticconstexpr

Definition at line 109 of file Bitfields.h.

Referenced by llvm::bitfields_details::Compressor< T, Bits, bool >::pack().

◆ Umin

template<typename T , unsigned Bits>

constexpr Unsigned llvm::bitfields_details::BitPatterns< T, Bits >::Umin = AllZeros

staticconstexpr

Definition at line 108 of file Bitfields.h.

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

include/llvm/ADT/Bitfields.h