bitops

Documentation

Overview

bitops provides various bitwise utilities on uint64s which are not supported by math.bits.

Index

• func FirstBits(n int, b uint64) uint64
• func LastBits(n int, b uint64) uint64
• func LeadingOnesMask(n int) uint64
• func OnesMask(leading, trailing int) uint64
• func SingleOneMask(idx int) uint64
• func TrailingOnesMask(n int) uint64

Functions

func FirstBits

func FirstBits(n int, b uint64) uint64

FirstBits returns a uint64 consisting of the first n bits of b, filled up with 0s.

func LastBits

func LastBits(n int, b uint64) uint64

LastBits returns a uint64 consisting of the last n bits of b, filled up with 0s.

func LeadingOnesMask

func LeadingOnesMask(n int) uint64

LeadingOnesMask returns a bitmask where the first n bits are 1, the others are 0.

If n lies outside the valid range of [0, 64], it will be coerced to the nearest valid value.

func OnesMask

func OnesMask(leading, trailing int) uint64

OnesMask returns a bitmask where the first leading and last trailing bits are 1, while the bits between are 0.

If either of leading or trailing lie outside the valid range of [0, 64], they will be coerced to the nearest valid value.

func SingleOneMask

func SingleOneMask(idx int) uint64

SingleOneMask returns a bitmask where the single bit at position idx is 1, while all others are 0.

If idx is outside the valid range of [0, 63] it is coerced to the nearest valid value.

func TrailingOnesMask

func TrailingOnesMask(n int) uint64

TrailingOnesMask returns a bitmask where the last n bits are 1, the others are 0.

If n lies outside the valid range of [0, 64], it will be coerced to the nearest valid value.