popcnt

Documentation

Overview

THESE PACKAGES ARE FOR DEMONSTRATION PURPOSES ONLY!

THEY DO NOT NOT CONTAIN WORKING INTRINSICS!

See https://github.com/klauspost/intrinsics

Index

• func Popcnt32(a int) int
• func Popcnt64(a int64) int
• func PopcntU32(a uint32) int
• func PopcntU64(a uint64) int64

Functions

func Popcnt32

func Popcnt32(a int) int

Popcnt32: Count the number of bits set to 1 in 32-bit integer 'a', and return that count in 'dst'.

dst := 0
FOR i := 0 to 31
	IF a[i]
		dst := dst + 1
	FI
ENDFOR

Instruction: 'POPCNT'. Intrinsic: '_popcnt32'. Requires POPCNT.

func Popcnt64

func Popcnt64(a int64) int

Popcnt64: Count the number of bits set to 1 in 64-bit integer 'a', and return that count in 'dst'.

dst := 0
FOR i := 0 to 63
	IF a[i]
		dst := dst + 1
	FI
ENDFOR

Instruction: 'POPCNT'. Intrinsic: '_popcnt64'. Requires POPCNT.

func PopcntU32

func PopcntU32(a uint32) int

PopcntU32: Count the number of bits set to 1 in unsigned 32-bit integer 'a', and return that count in 'dst'.

dst := 0
FOR i := 0 to 31
	IF a[i]
		dst := dst + 1
	FI
ENDFOR

Instruction: 'POPCNT'. Intrinsic: '_mm_popcnt_u32'. Requires POPCNT.

func PopcntU64

func PopcntU64(a uint64) int64

PopcntU64: Count the number of bits set to 1 in unsigned 64-bit integer 'a', and return that count in 'dst'.

dst := 0
FOR i := 0 to 63
	IF a[i]
		dst := dst + 1
	FI
ENDFOR

Instruction: 'POPCNT'. Intrinsic: '_mm_popcnt_u64'. Requires POPCNT.